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Sample records for management efficient scheme

  1. A High Fuel Consumption Efficiency Management Scheme for PHEVs Using an Adaptive Genetic Algorithm

    PubMed Central

    Lee, Wah Ching; Tsang, Kim Fung; Chi, Hao Ran; Hung, Faan Hei; Wu, Chung Kit; Chui, Kwok Tai; Lau, Wing Hong; Leung, Yat Wah

    2015-01-01

    A high fuel efficiency management scheme for plug-in hybrid electric vehicles (PHEVs) has been developed. In order to achieve fuel consumption reduction, an adaptive genetic algorithm scheme has been designed to adaptively manage the energy resource usage. The objective function of the genetic algorithm is implemented by designing a fuzzy logic controller which closely monitors and resembles the driving conditions and environment of PHEVs, thus trading off between petrol versus electricity for optimal driving efficiency. Comparison between calculated results and publicized data shows that the achieved efficiency of the fuzzified genetic algorithm is better by 10% than existing schemes. The developed scheme, if fully adopted, would help reduce over 600 tons of CO2 emissions worldwide every day. PMID:25587974

  2. A high fuel consumption efficiency management scheme for PHEVs using an adaptive genetic algorithm.

    PubMed

    Lee, Wah Ching; Tsang, Kim Fung; Chi, Hao Ran; Hung, Faan Hei; Wu, Chung Kit; Chui, Kwok Tai; Lau, Wing Hong; Leung, Yat Wah

    2015-01-01

    A high fuel efficiency management scheme for plug-in hybrid electric vehicles (PHEVs) has been developed. In order to achieve fuel consumption reduction, an adaptive genetic algorithm scheme has been designed to adaptively manage the energy resource usage. The objective function of the genetic algorithm is implemented by designing a fuzzy logic controller which closely monitors and resembles the driving conditions and environment of PHEVs, thus trading off between petrol versus electricity for optimal driving efficiency. Comparison between calculated results and publicized data shows that the achieved efficiency of the fuzzified genetic algorithm is better by 10% than existing schemes. The developed scheme, if fully adopted, would help reduce over 600 tons of CO2 emissions worldwide every day.

  3. An efficient key-management scheme for hierarchical access control in e-medicine system.

    PubMed

    Wu, Shuhua; Chen, Kefei

    2012-08-01

    In e-medicine system, the sharing of patients' medical histories scattered among medical institutions through the Internet is highly desirable. The most immediate cryptographic need certainly is an efficient key management method to solve dynamic access problems in a user hierarchy. In this paper, we propose a practical solution for dynamic access problem in a user hierarchy based on hybrid cryptosystems. When compared with Nikooghadam et al.'s scheme proposed most recently, the time complexity and the required storage space is reduced significantly. Moreover, it provides provable security, and is easy to implement. Therefore, our scheme is more suitable for e-medicine system.

  4. An Efficient Identity-Based Key Management Scheme for Wireless Sensor Networks Using the Bloom Filter

    PubMed Central

    Qin, Zhongyuan; Zhang, Xinshuai; Feng, Kerong; Zhang, Qunfang; Huang, Jie

    2014-01-01

    With the rapid development and widespread adoption of wireless sensor networks (WSNs), security has become an increasingly prominent problem. How to establish a session key in node communication is a challenging task for WSNs. Considering the limitations in WSNs, such as low computing capacity, small memory, power supply limitations and price, we propose an efficient identity-based key management (IBKM) scheme, which exploits the Bloom filter to authenticate the communication sensor node with storage efficiency. The security analysis shows that IBKM can prevent several attacks effectively with acceptable computation and communication overhead. PMID:25264955

  5. An Energy-Efficient Secure Routing and Key Management Scheme for Mobile Sinks in Wireless Sensor Networks Using Deployment Knowledge

    PubMed Central

    Hung, Le Xuan; Canh, Ngo Trong; Lee, Sungyoung; Lee, Young-Koo; Lee, Heejo

    2008-01-01

    For many sensor network applications such as military or homeland security, it is essential for users (sinks) to access the sensor network while they are moving. Sink mobility brings new challenges to secure routing in large-scale sensor networks. Previous studies on sink mobility have mainly focused on efficiency and effectiveness of data dissemination without security consideration. Also, studies and experiences have shown that considering security during design time is the best way to provide security for sensor network routing. This paper presents an energy-efficient secure routing and key management for mobile sinks in sensor networks, called SCODEplus. It is a significant extension of our previous study in five aspects: (1) Key management scheme and routing protocol are considered during design time to increase security and efficiency; (2) The network topology is organized in a hexagonal plane which supports more efficiency than previous square-grid topology; (3) The key management scheme can eliminate the impacts of node compromise attacks on links between non-compromised nodes; (4) Sensor node deployment is based on Gaussian distribution which is more realistic than uniform distribution; (5) No GPS or like is required to provide sensor node location information. Our security analysis demonstrates that the proposed scheme can defend against common attacks in sensor networks including node compromise attacks, replay attacks, selective forwarding attacks, sinkhole and wormhole, Sybil attacks, HELLO flood attacks. Both mathematical and simulation-based performance evaluation show that the SCODEplus significantly reduces the communication overhead, energy consumption, packet delivery latency while it always delivers more than 97 percent of packets successfully.

  6. A novel key management scheme using biometrics

    NASA Astrophysics Data System (ADS)

    Sui, Yan; Yang, Kai; Du, Yingzi; Orr, Scott; Zou, Xukai

    2010-04-01

    Key management is one of the most important issues in cryptographic systems. Several important challenges in such a context are represented by secure and efficient key generation, key distribution, as well as key revocation. Addressing such challenges requires a comprehensive solution which is robust, secure and efficient. Compared to traditional key management schemes, key management using biometrics requires the presence of the user, which can reduce fraud and protect the key better. In this paper, we propose a novel key management scheme using iris based biometrics. Our newly proposed scheme outperforms traditional key management schemes as well as some existing key-binding biometric schemes in terms of security, diversity and/or efficiency.

  7. How much are people willing to pay for efficient waste management schemes? A benefit transfer application.

    PubMed

    Damigos, Dimitris; Kaliampakos, Dimitris; Menegaki, Maria

    2016-04-01

    To socially justify the need for better municipal solid waste management services, especially in the light of the limited availability of public funds, it is important to quantify the monetary value of the potential social and environmental benefits offered by them. This article aims at estimating society's willingness to pay improved municipal solid waste management and establishing suitable reference values using the 'benefit transfer' method. To this direction, relevant studies from the global scientific and grey literature in the field of municipal solid waste management valuation are analysed and two different transfer approaches are implemented. According to the analysis, the mean annual willingness to pay per household is 88.4 USD(2014) (5%-trimmed mean: 78.7 USD(2014); 95% confidence interval lower bound: 64.8 USD(2014) and upper bound: 112.0 USD(2014)). The analysis yields estimates with a high standard deviation and notably broad confidence intervals, owing to design issues of the primary studies, the different socioeconomic profiles of the populations surveyed and the existing level of municipal solid waste management services. Thus, a meta-regression model is estimated to explore the sources of heterogeneity and facilitate more accurate transfer values. Nevertheless, the limited number of observations and some methodological issues in the design and conduct of the original surveys set certain challenges and increase the level of uncertainty of the transfer values. PMID:26917560

  8. Efficient DSMC collision-partner selection schemes.

    SciTech Connect

    Gallis, Michail A.; Torczynski, John Robert

    2010-07-01

    The effect of collision-partner selection schemes on the accuracy and the efficiency of the Direct Simulation Monte Carlo (DSMC) method of Bird is investigated. Several schemes to reduce the total discretization error as a function of the mean collision separation and the mean collision time are examined. These include the historically first sub-cell scheme, the more recent nearest-neighbor scheme, and various near-neighbor schemes, which are evaluated for their effect on the thermal conductivity for Fourier flow. Their convergence characteristics as a function of spatial and temporal discretization and the number of simulators per cell are compared to the convergence characteristics of the sophisticated and standard DSMC algorithms. Improved performance is obtained if the population from which possible collision partners are selected is an appropriate fraction of the population of the cell.

  9. Efficient DSMC collision-partner selection schemes.

    SciTech Connect

    Gallis, Michail A.; Torczynski, John Robert

    2010-05-01

    The effect of collision-partner selection schemes on the accuracy and the efficiency of the Direct Simulation Monte Carlo (DSMC) method of Bird is investigated. Several schemes to reduce the total discretization error as a function of the mean collision separation and the mean collision time are examined. These include the historically first sub-cell scheme, the more recent nearest-neighbor scheme, and various near-neighbor schemes, which are evaluated for their effect on the thermal conductivity for Fourier flow. Their convergence characteristics as a function of spatial and temporal discretization and the number of simulators per cell are compared to the convergence characteristics of the sophisticated and standard DSMC algorithms. Improved performance is obtained if the population from which possible collision partners are selected is an appropriate fraction of the population of the cell.

  10. Efficient Conservative Reformulation Schemes for Lithium Intercalation

    SciTech Connect

    Urisanga, PC; Rife, D; De, S; Subramanian, VR

    2015-02-18

    Porous electrode theory coupled with transport and reaction mechanisms is a widely used technique to model Li-ion batteries employing an appropriate discretization or approximation for solid phase diffusion with electrode particles. One of the major difficulties in simulating Li-ion battery models is the need to account for solid phase diffusion in a second radial dimension r, which increases the computation time/cost to a great extent. Various methods that reduce the computational cost have been introduced to treat this phenomenon, but most of them do not guarantee mass conservation. The aim of this paper is to introduce an inherently mass conserving yet computationally efficient method for solid phase diffusion based on Lobatto III A quadrature. This paper also presents coupling of the new solid phase reformulation scheme with a macro-homogeneous porous electrode theory based pseudo 20 model for Li-ion battery. (C) The Author(s) 2015. Published by ECS. All rights reserved.

  11. An efficient authentication scheme for telecare medicine information systems.

    PubMed

    Zhu, Zhian

    2012-12-01

    To ensure patients' privacy, such as telephone number, medical record number, health information, etc., authentication schemes for telecare medicine information systems (TMIS) have been studied widely. Recently, Wei et al. proposed an efficient authentication scheme for TMIS. They claimed their scheme could resist various attacks. However, in this paper, we will show their scheme is vulnerable to an off-line password guessing attack when user's smart card is lost. To improve the security, we propose a new authentication scheme for TMIS. The analysis shows our scheme could overcome the weaknesses in Wei et al.'s scheme and has better performance than their scheme. PMID:22527784

  12. An efficient compression scheme for bitmap indices

    SciTech Connect

    Wu, Kesheng; Otoo, Ekow J.; Shoshani, Arie

    2004-04-13

    When using an out-of-core indexing method to answer a query, it is generally assumed that the I/O cost dominates the overall query response time. Because of this, most research on indexing methods concentrate on reducing the sizes of indices. For bitmap indices, compression has been used for this purpose. However, in most cases, operations on these compressed bitmaps, mostly bitwise logical operations such as AND, OR, and NOT, spend more time in CPU than in I/O. To speedup these operations, a number of specialized bitmap compression schemes have been developed; the best known of which is the byte-aligned bitmap code (BBC). They are usually faster in performing logical operations than the general purpose compression schemes, but, the time spent in CPU still dominates the total query response time. To reduce the query response time, we designed a CPU-friendly scheme named the word-aligned hybrid (WAH) code. In this paper, we prove that the sizes of WAH compressed bitmap indices are about two words per row for large range of attributes. This size is smaller than typical sizes of commonly used indices, such as a B-tree. Therefore, WAH compressed indices are not only appropriate for low cardinality attributes but also for high cardinality attributes.In the worst case, the time to operate on compressed bitmaps is proportional to the total size of the bitmaps involved. The total size of the bitmaps required to answer a query on one attribute is proportional to the number of hits. These indicate that WAH compressed bitmap indices are optimal. To verify their effectiveness, we generated bitmap indices for four different datasets and measured the response time of many range queries. Tests confirm that sizes of compressed bitmap indices are indeed smaller than B-tree indices, and query processing with WAH compressed indices is much faster than with BBC compressed indices, projection indices and B-tree indices. In addition, we also verified that the average query response time

  13. Secure SCADA communication by using a modified key management scheme.

    PubMed

    Rezai, Abdalhossein; Keshavarzi, Parviz; Moravej, Zahra

    2013-07-01

    This paper presents and evaluates a new cryptographic key management scheme which increases the efficiency and security of the Supervisory Control And Data Acquisition (SCADA) communication. In the proposed key management scheme, two key update phases are used: session key update and master key update. In the session key update phase, session keys are generated in the master station. In the master key update phase, the Elliptic Curve Diffie-Hellman (ECDH) protocol is used. The Poisson process is also used to model the Security Index (SI) and Quality of Service (QoS). Our analysis shows that the proposed key management not only supports the required speed in the MODBUS implementation but also has several advantages compared to other key management schemes for secure communication in SCADA networks.

  14. Secure SCADA communication by using a modified key management scheme.

    PubMed

    Rezai, Abdalhossein; Keshavarzi, Parviz; Moravej, Zahra

    2013-07-01

    This paper presents and evaluates a new cryptographic key management scheme which increases the efficiency and security of the Supervisory Control And Data Acquisition (SCADA) communication. In the proposed key management scheme, two key update phases are used: session key update and master key update. In the session key update phase, session keys are generated in the master station. In the master key update phase, the Elliptic Curve Diffie-Hellman (ECDH) protocol is used. The Poisson process is also used to model the Security Index (SI) and Quality of Service (QoS). Our analysis shows that the proposed key management not only supports the required speed in the MODBUS implementation but also has several advantages compared to other key management schemes for secure communication in SCADA networks. PMID:23528753

  15. An Efficient Variable-Length Data-Compression Scheme

    NASA Technical Reports Server (NTRS)

    Cheung, Kar-Ming; Kiely, Aaron B.

    1996-01-01

    Adaptive variable-length coding scheme for compression of stream of independent and identically distributed source data involves either Huffman code or alternating run-length Huffman (ARH) code, depending on characteristics of data. Enables efficient compression of output of lossless or lossy precompression process, with speed and simplicity greater than those of older coding schemes developed for same purpose. In addition, scheme suitable for parallel implementation on hardware with modular structure, provides for rapid adaptation to changing data source, compatible with block orientation to alleviate memory requirements, ensures efficiency over wide range of entropy, and easily combined with such other communication schemes as those for containment of errors and for packetization.

  16. A Secure and Efficient Threshold Group Signature Scheme

    NASA Astrophysics Data System (ADS)

    Zhang, Yansheng; Wang, Xueming; Qiu, Gege

    The paper presents a secure and efficient threshold group signature scheme aiming at two problems of current threshold group signature schemes: conspiracy attack and inefficiency. Scheme proposed in this paper takes strategy of separating designed clerk who is responsible for collecting and authenticating each individual signature from group, the designed clerk don't participate in distribution of group secret key and has his own public key and private key, designed clerk needs to sign part information of threshold group signature after collecting signatures. Thus verifier has to verify signature of the group after validating signature of the designed clerk. This scheme is proved to be secure against conspiracy attack at last and is more efficient by comparing with other schemes.

  17. Improved-efficiency DSMC collision-partner selection schemes.

    SciTech Connect

    Gallis, Michail A.; Torczynski, John Robert

    2010-11-01

    The effect of collision-partner selection schemes on the accuracy and the efficiency of the Direct Simulation Monte Carlo (DSMC) method of Bird is investigated. Several schemes to reduce the total discretization error as a function of the mean collision separation and the mean collision time are examined. These include the historically first sub-cell scheme, the more recent nearest-neighbor scheme, and various near-neighbor schemes, which are evaluated for their effect on the thermal conductivity for Fourier flow. Their convergence characteristics as a function of spatial and temporal discretization and the number of simulators per cell are compared to the convergence characteristics of the sophisticated and standard DSMC algorithms. Improved performance is obtained if the population from which possible collision partners are selected is an appropriate fraction of the population of the cell.

  18. An Efficient Scheme for Updating Sparse Cholesky Factors

    NASA Technical Reports Server (NTRS)

    Raghavan, Padma

    2002-01-01

    Raghavan had earlier developed the software package DCSPACK which can be used for solving sparse linear systems where the coefficient matrix is symmetric and positive definite (this project was not funded by NASA but by agencies such as NSF). DSCPACK-S is the serial code and DSCPACK-P is a parallel implementation suitable for multiprocessors or networks-of-workstations with message passing using MCI. The main algorithm used is the Cholesky factorization of a sparse symmetric positive positive definite matrix A = LL(T). The code can also compute the factorization A = LDL(T). The complexity of the software arises from several factors relating to the sparsity of the matrix A. A sparse N x N matrix A has typically less that cN nonzeroes where c is a small constant. If the matrix were dense, it would have O(N2) nonzeroes. The most complicated part of such sparse Cholesky factorization relates to fill-in, i.e., zeroes in the original matrix that become nonzeroes in the factor L. An efficient implementation depends to a large extent on complex data structures and on techniques from graph theory to reduce, identify, and manage fill. DSCPACK is based on an efficient multifrontal implementation with fill-managing algorithms and implementation arising from earlier research by Raghavan and others. Sparse Cholesky factorization is typically a four step process: (1) ordering to compute a fill-reducing numbering, (2) symbolic factorization to determine the nonzero structure of L, (3) numeric factorization to compute L, and, (4) triangular solution to solve L(T)x = y and Ly = b. The first two steps are symbolic and are performed using the graph of the matrix. The numeric factorization step is of dominant cost and there are several schemes for improving performance by exploiting the nested and dense structure of groups of columns in the factor. The latter are aimed at better utilization of the cache-memory hierarchy on modem processors to prevent cache-misses and provide execution

  19. Motor efficiency management

    SciTech Connect

    Lobodovsky, K.K. , Penn Valley, CA )

    1994-01-01

    During the 102nd Congress, the Markey Bill, H.R. 2451, was introduced. The bill mandated component efficiency standards for such products as lighting, distribution transformers, and electric A.C. motors. This plan was met with opposition by NEMA and other interested groups. They called for a system approach that would recognize the complex nature of the product involved under the plan. The bill passed by the Energy Power Subcommittee on the theory that the elimination of the least efficient component from the market would ensure that consumers would purchase and use the most efficient products possible. Experience indicates that despite heightened awareness and concern with energy efficiency, the electric motor is either completely neglected or decisions are made on the basis of incomplete information. An on-going analysis of motor performance prevents major breakdown. Performance evaluation of a motor should be done as routinely as it is done on an employee. Both the motor and the employee are equally important. Applied motor maintenance will keep the building or plant running smoothly with minimal stress on the system or downtime because of failure. The Motor Performance Management Process (MPMP) is designed to be the Motor Manager's primary tool to evaluate, measure, and most importantly manage electric motors. MPMP focuses on building a stronger relationship between the Motor Manager and the electric motor employed to perform a task. Specifically, it is a logical, systematic, and structured approach to reduce energy waste. Energy waste reduction is fundamental in becoming more efficient in an increasingly competitive market. The implementation of MPMP is more than a good business practice it is an intelligent management resource.

  20. Efficient scheme for parametric fitting of data in arbitrary dimensions.

    PubMed

    Pang, Ning-Ning; Tzeng, Wen-Jer; Kao, Hisen-Ching

    2008-07-01

    We propose an efficient scheme for parametric fitting expressed in terms of the Legendre polynomials. For continuous systems, our scheme is exact and the derived explicit expression is very helpful for further analytical studies. For discrete systems, our scheme is almost as accurate as the method of singular value decomposition. Through a few numerical examples, we show that our algorithm costs much less CPU time and memory space than the method of singular value decomposition. Thus, our algorithm is very suitable for a large amount of data fitting. In addition, the proposed scheme can also be used to extract the global structure of fluctuating systems. We then derive the exact relation between the correlation function and the detrended variance function of fluctuating systems in arbitrary dimensions and give a general scaling analysis.

  1. Compound management beyond efficiency.

    PubMed

    Burr, Ian; Winchester, Toby; Keighley, Wilma; Sewing, Andreas

    2009-06-01

    Codeveloping alongside chemistry and in vitro screening, compound management was one of the first areas in research recognizing the need for efficient processes and workflows. Material management groups have centralized, automated, miniaturized and, importantly, found out what not to do with compounds. While driving down cost and improving quality in storage and processing, researchers still face the challenge of interfacing optimally with changing business processes, in screening groups, and with external vendors and focusing on biologicals in many companies. Here we review our strategy to provide a seamless link between compound acquisition and screening operations and the impact of material management on quality of the downstream processes. Although this is driven in part by new technologies and improved quality control within material management, redefining team structures and roles also drives job satisfaction and motivation in our teams with a subsequent positive impact on cycle times and customer feedback.

  2. Cost efficient command management

    NASA Technical Reports Server (NTRS)

    Brandt, Theresa; Murphy, C. W.; Kuntz, Jon; Barlett, Tom

    1996-01-01

    The design and implementation of a command management system (CMS) for a NASA control center, is described. The technology innovations implemented in the CMS provide the infrastructure required for operations cost reduction and future development cost reduction through increased operational efficiency and reuse in future missions. The command management design facilitates error-free operations which enables the automation of the routine control center functions and allows for the distribution of scheduling responsibility to the instrument teams. The reusable system was developed using object oriented methodologies.

  3. Dutch approach to develop efficient water quality monitoring schemes

    NASA Astrophysics Data System (ADS)

    Schoumans, O. F.; van Tol-Leenders, T. P.; van der Bolt, F. J. E.; Siderius, C.; Kroes, J.; Roelsma, J.; Löschner-Wolleswinkel, R.; Walvoort, D.

    2009-04-01

    In 2003 a study started to determine a monitoring procedure in order to quantify the impact of the Dutch manure legislation on water quality at catchment scale. Four catchments were selected to develop such a methodology. One peat catchment, one clay catchment and two sandy catchments were selected as representative catchments for the major soil types that occur in The Netherlands. The contribution of land to the diffuse pollution of surface water depends on a lot of factors, such as meteorological circumstances, hydrological conditions, soil characteristics, soil properties and soil status, land use, manure and fertilizer application rates, hydraulic conditions etc. As a result different sources and pathways can be distinguished, that will changes over time. As a result of this complexity it is impossible to determine the influence of all these factors separately and independently just by measuring the water quality of the surface water. For this reason a monitoring scheme was developed for catchment scale in which measurements were combined with process oriented modeling approaches for the land-water-system as a whole. A validated process oriented modeling approach is necessary in order to understand the fate of nutrients applied with manure and fertilizers and to assess what will happen over time for each specific catchment system. Furthermore, the model can be used to adjust the location of the gauging stations and the frequency of the measurements and can fill in gaps in the data of the measurements. In fact the whole monitoring procedure is an iterative process between measurements and modeling and will end up in an efficient monitoring approach. Furthermore, the measurements are used to increase the validation of the tools. In the near future this monitoring approach of measuring and modeling will be used to determine to what extend the different management strategies will effect diffuse nutrient losses to surface water. So, Measuring, Modeling and

  4. A complete hierarchical key management scheme for heterogeneous wireless sensor networks.

    PubMed

    Chen, Chien-Ming; Zheng, Xinying; Wu, Tsu-Yang

    2014-01-01

    Heterogeneous cluster-based wireless sensor networks (WSN) attracted increasing attention recently. Obviously, the clustering makes the entire networks hierarchical; thus, several kinds of keys are required for hierarchical network topology. However, most existing key management schemes for it place more emphasis on pairwise key management schemes or key predistribution schemes and neglect the property of hierarchy. In this paper, we propose a complete hierarchical key management scheme which only utilizes symmetric cryptographic algorithms and low cost operations for heterogeneous cluster-based WSN. Our scheme considers four kinds of keys, which are an individual key, a cluster key, a master key, and pairwise keys, for each sensor node. Finally, the analysis and experiments demonstrate that the proposed scheme is secure and efficient; thus, it is suitable for heterogeneous cluster-based WSN.

  5. A Complete Hierarchical Key Management Scheme for Heterogeneous Wireless Sensor Networks

    PubMed Central

    Zheng, Xinying

    2014-01-01

    Heterogeneous cluster-based wireless sensor networks (WSN) attracted increasing attention recently. Obviously, the clustering makes the entire networks hierarchical; thus, several kinds of keys are required for hierarchical network topology. However, most existing key management schemes for it place more emphasis on pairwise key management schemes or key predistribution schemes and neglect the property of hierarchy. In this paper, we propose a complete hierarchical key management scheme which only utilizes symmetric cryptographic algorithms and low cost operations for heterogeneous cluster-based WSN. Our scheme considers four kinds of keys, which are an individual key, a cluster key, a master key, and pairwise keys, for each sensor node. Finally, the analysis and experiments demonstrate that the proposed scheme is secure and efficient; thus, it is suitable for heterogeneous cluster-based WSN. PMID:24983001

  6. Energy Efficient Cluster Based Scheduling Scheme for Wireless Sensor Networks

    PubMed Central

    Srie Vidhya Janani, E.; Ganesh Kumar, P.

    2015-01-01

    The energy utilization of sensor nodes in large scale wireless sensor network points out the crucial need for scalable and energy efficient clustering protocols. Since sensor nodes usually operate on batteries, the maximum utility of network is greatly dependent on ideal usage of energy leftover in these sensor nodes. In this paper, we propose an Energy Efficient Cluster Based Scheduling Scheme for wireless sensor networks that balances the sensor network lifetime and energy efficiency. In the first phase of our proposed scheme, cluster topology is discovered and cluster head is chosen based on remaining energy level. The cluster head monitors the network energy threshold value to identify the energy drain rate of all its cluster members. In the second phase, scheduling algorithm is presented to allocate time slots to cluster member data packets. Here congestion occurrence is totally avoided. In the third phase, energy consumption model is proposed to maintain maximum residual energy level across the network. Moreover, we also propose a new packet format which is given to all cluster member nodes. The simulation results prove that the proposed scheme greatly contributes to maximum network lifetime, high energy, reduced overhead, and maximum delivery ratio. PMID:26495417

  7. An Energy Efficient Instruction Prefetching Scheme for Embedded Processors

    NASA Astrophysics Data System (ADS)

    Gu, Ji; Guo, Hui

    Existing instruction prefetching schemes improve performance with significant energy sacrifice, making them unsuitable for embedded and ubiquitous systems where high performance and low energy consumption are all demanded. In this paper, we reduce energy overhead in instruction prefetching by using a simple prefetching hardware/software design and an efficient prefetching operation scheme. Two approaches are investigated: one, Decoded Loop Instruction Cache based Prefetching (DLICP) that is most effective for loop intensive applications; two, enhanced DLICP with the popular existing Next Line Prefetching (NLP) for applications of a moderate number of loops. Our experimental results show that both DLICP and enhanced DLICP deliver improved performance at greatly reduced energy overhead. Up to 21% performance can be improved by the enhanced DLICP at about 3.5% energy overhead, as in comparison to the maximal 11% performance improvement and 49% energy overhead from NLP.

  8. A key management scheme for tiered wireless sensor network with self-healing capability

    NASA Astrophysics Data System (ADS)

    Wang, Maoyu; Tang, Helen; Yu, F. R.

    2013-05-01

    This paper presents a novel key management scheme for a tiered self-healing wireless sensor network. A tiered wireless sensor network with self-healing features draws extensive attention because of its scalability, robustness and reliability. A tiered key management scheme to support the cluster membership and the self-healing features is proposed with emphasis on the control of a node's participation and re-keying when joining a new cluster. The security and overhead analysis demonstrates the proposed scheme is effective and efficient with respect to communication, computation, and memory overhead for operation in a hostile environment.

  9. A Query Result Merging Scheme for Providing Energy Efficiency in Underwater Sensor Networks

    PubMed Central

    Kim, Yunsung; Park, Soo-Hyun

    2011-01-01

    Underwater sensor networks are emerging as a promising distributed data management system for various applications in underwater environments, despite their limited accessibility and restricted energy capacity. With the aid of recent developments in ubiquitous data computing, an increasing number of users are expected to overcome low accessibility by applying queries to underwater sensor networks. However, when multiple users send queries to an underwater sensor network in a disorganized manner, it may incur lethal energy waste and problematic network traffic. The current query management mechanisms cannot effectively deal with this matter due to their limited applicability and unrealistic assumptions. In this paper, a novel query management scheme involving query result merging is proposed for underwater sensor networks. The mechanism is based on a relational database model and is adjusted to the practical restrictions affecting underwater communication environments. Network simulations will prove that the scheme becomes more efficient with a greater number of queries and a smaller period range. PMID:22247695

  10. A query result merging scheme for providing energy efficiency in underwater sensor networks.

    PubMed

    Kim, Yunsung; Park, Soo-Hyun

    2011-01-01

    Underwater sensor networks are emerging as a promising distributed data management system for various applications in underwater environments, despite their limited accessibility and restricted energy capacity. With the aid of recent developments in ubiquitous data computing, an increasing number of users are expected to overcome low accessibility by applying queries to underwater sensor networks. However, when multiple users send queries to an underwater sensor network in a disorganized manner, it may incur lethal energy waste and problematic network traffic. The current query management mechanisms cannot effectively deal with this matter due to their limited applicability and unrealistic assumptions. In this paper, a novel query management scheme involving query result merging is proposed for underwater sensor networks. The mechanism is based on a relational database model and is adjusted to the practical restrictions affecting underwater communication environments. Network simulations will prove that the scheme becomes more efficient with a greater number of queries and a smaller period range.

  11. A Distributed Network Mobility Management Scheme for Hierarchical Mobile IPv6 Networks

    NASA Astrophysics Data System (ADS)

    Kawano, Keita; Kinoshita, Kazuhiko; Yamai, Nariyoshi

    Route optimization for network mobility is a key technique for providing a node in a mobile network (Mobile Network Node or MNN) with high quality broadband communications. Many schemes adding route optimization function to Network Mobility (NEMO) Basic Support protocol, the standardized network mobility management protocol from the IETF nemo working group, have already been proposed in recent years. One such scheme, a scheme using Hierarchical Mobile IPv6 (HMIPv6) aims to overcome micromobility management issues as well by applying a mechanism based on HMIPv6. The traditional scheme, however, suffers from a significant number of signaling messages as the number of MNNs and/or the number of their Correspondent Nodes (CNs) increase, because many messages notifying the MNNs' Home Agents (HAMNNs) and the CNs of the mobile network's movement are generated simultaneously each time the mobile network moves to the domain of another micromobility management router (Mobility Anchor Point or MAP). This paper proposes a scheme to overcome this problem. Our scheme reduces the number of signaling messages generated at the same time by managing the mobility of MNNs using multiple MAPs distributed within a network for load sharing. The results of simulation experiments show that our scheme works efficiently compared to the traditional scheme when a mobile network has many MNNs and/or these MNNs communicate with many CNs.

  12. A Watermarking Scheme for High Efficiency Video Coding (HEVC)

    PubMed Central

    Swati, Salahuddin; Hayat, Khizar; Shahid, Zafar

    2014-01-01

    This paper presents a high payload watermarking scheme for High Efficiency Video Coding (HEVC). HEVC is an emerging video compression standard that provides better compression performance as compared to its predecessor, i.e. H.264/AVC. Considering that HEVC may will be used in a variety of applications in the future, the proposed algorithm has a high potential of utilization in applications involving broadcast and hiding of metadata. The watermark is embedded into the Quantized Transform Coefficients (QTCs) during the encoding process. Later, during the decoding process, the embedded message can be detected and extracted completely. The experimental results show that the proposed algorithm does not significantly affect the video quality, nor does it escalate the bitrate. PMID:25144455

  13. A watermarking scheme for High Efficiency Video Coding (HEVC).

    PubMed

    Swati, Salahuddin; Hayat, Khizar; Shahid, Zafar

    2014-01-01

    This paper presents a high payload watermarking scheme for High Efficiency Video Coding (HEVC). HEVC is an emerging video compression standard that provides better compression performance as compared to its predecessor, i.e. H.264/AVC. Considering that HEVC may will be used in a variety of applications in the future, the proposed algorithm has a high potential of utilization in applications involving broadcast and hiding of metadata. The watermark is embedded into the Quantized Transform Coefficients (QTCs) during the encoding process. Later, during the decoding process, the embedded message can be detected and extracted completely. The experimental results show that the proposed algorithm does not significantly affect the video quality, nor does it escalate the bitrate.

  14. Efficient and Anonymous Authentication Scheme for Wireless Body Area Networks.

    PubMed

    Wu, Libing; Zhang, Yubo; Li, Li; Shen, Jian

    2016-06-01

    As a significant part of the Internet of Things (IoT), Wireless Body Area Network (WBAN) has attract much attention in this years. In WBANs, sensors placed in or around the human body collect the sensitive data of the body and transmit it through an open wireless channel in which the messages may be intercepted, modified, etc. Recently, Wang et al. presented a new anonymous authentication scheme for WBANs and claimed that their scheme can solve the security problems in the previous schemes. Unfortunately, we demonstrate that their scheme cannot withstand impersonation attack. Either an adversary or a malicious legal client could impersonate another legal client to the application provider. In this paper, we give the detailed weakness analysis of Wang et al.'s scheme at first. Then we present a novel anonymous authentication scheme for WBANs and prove that it's secure under a random oracle model. At last, we demonstrate that our presented anonymous authentication scheme for WBANs is more suitable for practical application than Wang et al.'s scheme due to better security and performance. Compared with Wang et al.'s scheme, the computation cost of our scheme in WBANs has reduced by about 31.58%.

  15. Efficient and Anonymous Authentication Scheme for Wireless Body Area Networks.

    PubMed

    Wu, Libing; Zhang, Yubo; Li, Li; Shen, Jian

    2016-06-01

    As a significant part of the Internet of Things (IoT), Wireless Body Area Network (WBAN) has attract much attention in this years. In WBANs, sensors placed in or around the human body collect the sensitive data of the body and transmit it through an open wireless channel in which the messages may be intercepted, modified, etc. Recently, Wang et al. presented a new anonymous authentication scheme for WBANs and claimed that their scheme can solve the security problems in the previous schemes. Unfortunately, we demonstrate that their scheme cannot withstand impersonation attack. Either an adversary or a malicious legal client could impersonate another legal client to the application provider. In this paper, we give the detailed weakness analysis of Wang et al.'s scheme at first. Then we present a novel anonymous authentication scheme for WBANs and prove that it's secure under a random oracle model. At last, we demonstrate that our presented anonymous authentication scheme for WBANs is more suitable for practical application than Wang et al.'s scheme due to better security and performance. Compared with Wang et al.'s scheme, the computation cost of our scheme in WBANs has reduced by about 31.58%. PMID:27091755

  16. Resource management scheme based on ubiquitous data analysis.

    PubMed

    Lee, Heung Ki; Jung, Jaehee; Yi, Gangman

    2014-01-01

    Resource management of the main memory and process handler is critical to enhancing the system performance of a web server. Owing to the transaction delay time that affects incoming requests from web clients, web server systems utilize several web processes to anticipate future requests. This procedure is able to decrease the web generation time because there are enough processes to handle the incoming requests from web browsers. However, inefficient process management results in low service quality for the web server system. Proper pregenerated process mechanisms are required for dealing with the clients' requests. Unfortunately, it is difficult to predict how many requests a web server system is going to receive. If a web server system builds too many web processes, it wastes a considerable amount of memory space, and thus performance is reduced. We propose an adaptive web process manager scheme based on the analysis of web log mining. In the proposed scheme, the number of web processes is controlled through prediction of incoming requests, and accordingly, the web process management scheme consumes the least possible web transaction resources. In experiments, real web trace data were used to prove the improved performance of the proposed scheme. PMID:25197692

  17. An effective and secure key-management scheme for hierarchical access control in E-medicine system.

    PubMed

    Odelu, Vanga; Das, Ashok Kumar; Goswami, Adrijit

    2013-04-01

    Recently several hierarchical access control schemes are proposed in the literature to provide security of e-medicine systems. However, most of them are either insecure against 'man-in-the-middle attack' or they require high storage and computational overheads. Wu and Chen proposed a key management method to solve dynamic access control problems in a user hierarchy based on hybrid cryptosystem. Though their scheme improves computational efficiency over Nikooghadam et al.'s approach, it suffers from large storage space for public parameters in public domain and computational inefficiency due to costly elliptic curve point multiplication. Recently, Nikooghadam and Zakerolhosseini showed that Wu-Chen's scheme is vulnerable to man-in-the-middle attack. In order to remedy this security weakness in Wu-Chen's scheme, they proposed a secure scheme which is again based on ECC (elliptic curve cryptography) and efficient one-way hash function. However, their scheme incurs huge computational cost for providing verification of public information in the public domain as their scheme uses ECC digital signature which is costly when compared to symmetric-key cryptosystem. In this paper, we propose an effective access control scheme in user hierarchy which is only based on symmetric-key cryptosystem and efficient one-way hash function. We show that our scheme reduces significantly the storage space for both public and private domains, and computational complexity when compared to Wu-Chen's scheme, Nikooghadam-Zakerolhosseini's scheme, and other related schemes. Through the informal and formal security analysis, we further show that our scheme is secure against different attacks and also man-in-the-middle attack. Moreover, dynamic access control problems in our scheme are also solved efficiently compared to other related schemes, making our scheme is much suitable for practical applications of e-medicine systems.

  18. An effective and secure key-management scheme for hierarchical access control in E-medicine system.

    PubMed

    Odelu, Vanga; Das, Ashok Kumar; Goswami, Adrijit

    2013-04-01

    Recently several hierarchical access control schemes are proposed in the literature to provide security of e-medicine systems. However, most of them are either insecure against 'man-in-the-middle attack' or they require high storage and computational overheads. Wu and Chen proposed a key management method to solve dynamic access control problems in a user hierarchy based on hybrid cryptosystem. Though their scheme improves computational efficiency over Nikooghadam et al.'s approach, it suffers from large storage space for public parameters in public domain and computational inefficiency due to costly elliptic curve point multiplication. Recently, Nikooghadam and Zakerolhosseini showed that Wu-Chen's scheme is vulnerable to man-in-the-middle attack. In order to remedy this security weakness in Wu-Chen's scheme, they proposed a secure scheme which is again based on ECC (elliptic curve cryptography) and efficient one-way hash function. However, their scheme incurs huge computational cost for providing verification of public information in the public domain as their scheme uses ECC digital signature which is costly when compared to symmetric-key cryptosystem. In this paper, we propose an effective access control scheme in user hierarchy which is only based on symmetric-key cryptosystem and efficient one-way hash function. We show that our scheme reduces significantly the storage space for both public and private domains, and computational complexity when compared to Wu-Chen's scheme, Nikooghadam-Zakerolhosseini's scheme, and other related schemes. Through the informal and formal security analysis, we further show that our scheme is secure against different attacks and also man-in-the-middle attack. Moreover, dynamic access control problems in our scheme are also solved efficiently compared to other related schemes, making our scheme is much suitable for practical applications of e-medicine systems. PMID:23392626

  19. An efficient quantum scheme for Private Set Intersection

    NASA Astrophysics Data System (ADS)

    Shi, Run-hua; Mu, Yi; Zhong, Hong; Cui, Jie; Zhang, Shun

    2016-01-01

    Private Set Intersection allows a client to privately compute set intersection with the collaboration of the server, which is one of the most fundamental and key problems within the multiparty collaborative computation of protecting the privacy of the parties. In this paper, we first present a cheat-sensitive quantum scheme for Private Set Intersection. Compared with classical schemes, our scheme has lower communication complexity, which is independent of the size of the server's set. Therefore, it is very suitable for big data services in Cloud or large-scale client-server networks.

  20. Key Management Scheme Based on Route Planning of Mobile Sink in Wireless Sensor Networks.

    PubMed

    Zhang, Ying; Liang, Jixing; Zheng, Bingxin; Jiang, Shengming; Chen, Wei

    2016-01-29

    In many wireless sensor network application scenarios the key management scheme with a Mobile Sink (MS) should be fully investigated. This paper proposes a key management scheme based on dynamic clustering and optimal-routing choice of MS. The concept of Traveling Salesman Problem with Neighbor areas (TSPN) in dynamic clustering for data exchange is proposed, and the selection probability is used in MS route planning. The proposed scheme extends static key management to dynamic key management by considering the dynamic clustering and mobility of MSs, which can effectively balance the total energy consumption during the activities. Considering the different resources available to the member nodes and sink node, the session key between cluster head and MS is established by modified an ECC encryption with Diffie-Hellman key exchange (ECDH) algorithm and the session key between member node and cluster head is built with a binary symmetric polynomial. By analyzing the security of data storage, data transfer and the mechanism of dynamic key management, the proposed scheme has more advantages to help improve the resilience of the key management system of the network on the premise of satisfying higher connectivity and storage efficiency.

  1. Key Management Scheme Based on Route Planning of Mobile Sink in Wireless Sensor Networks

    PubMed Central

    Zhang, Ying; Liang, Jixing; Zheng, Bingxin; Jiang, Shengming; Chen, Wei

    2016-01-01

    In many wireless sensor network application scenarios the key management scheme with a Mobile Sink (MS) should be fully investigated. This paper proposes a key management scheme based on dynamic clustering and optimal-routing choice of MS. The concept of Traveling Salesman Problem with Neighbor areas (TSPN) in dynamic clustering for data exchange is proposed, and the selection probability is used in MS route planning. The proposed scheme extends static key management to dynamic key management by considering the dynamic clustering and mobility of MSs, which can effectively balance the total energy consumption during the activities. Considering the different resources available to the member nodes and sink node, the session key between cluster head and MS is established by modified an ECC encryption with Diffie-Hellman key exchange (ECDH) algorithm and the session key between member node and cluster head is built with a binary symmetric polynomial. By analyzing the security of data storage, data transfer and the mechanism of dynamic key management, the proposed scheme has more advantages to help improve the resilience of the key management system of the network on the premise of satisfying higher connectivity and storage efficiency. PMID:26840311

  2. Key Management Scheme Based on Route Planning of Mobile Sink in Wireless Sensor Networks.

    PubMed

    Zhang, Ying; Liang, Jixing; Zheng, Bingxin; Jiang, Shengming; Chen, Wei

    2016-01-01

    In many wireless sensor network application scenarios the key management scheme with a Mobile Sink (MS) should be fully investigated. This paper proposes a key management scheme based on dynamic clustering and optimal-routing choice of MS. The concept of Traveling Salesman Problem with Neighbor areas (TSPN) in dynamic clustering for data exchange is proposed, and the selection probability is used in MS route planning. The proposed scheme extends static key management to dynamic key management by considering the dynamic clustering and mobility of MSs, which can effectively balance the total energy consumption during the activities. Considering the different resources available to the member nodes and sink node, the session key between cluster head and MS is established by modified an ECC encryption with Diffie-Hellman key exchange (ECDH) algorithm and the session key between member node and cluster head is built with a binary symmetric polynomial. By analyzing the security of data storage, data transfer and the mechanism of dynamic key management, the proposed scheme has more advantages to help improve the resilience of the key management system of the network on the premise of satisfying higher connectivity and storage efficiency. PMID:26840311

  3. Efficient energy stable numerical schemes for a phase field moving contact line model

    NASA Astrophysics Data System (ADS)

    Shen, Jie; Yang, Xiaofeng; Yu, Haijun

    2015-03-01

    In this paper, we present two efficient energy stable schemes to solve a phase field model incorporating moving contact line. The model is a coupled system that consists of incompressible Navier-Stokes equations with a generalized Navier boundary condition and Cahn-Hilliard equation in conserved form. In both schemes the projection method is used to deal with the Navier-Stokes equations and stabilization approach is used for the non-convex Ginzburg-Landau bulk potential. By some subtle explicit-implicit treatments, we obtain a linear coupled energy stable scheme for systems with dynamic contact line conditions and a linear decoupled energy stable scheme for systems with static contact line conditions. An efficient spectral-Galerkin spatial discretization method is implemented to verify the accuracy and efficiency of proposed schemes. Numerical results show that the proposed schemes are very efficient and accurate.

  4. [Farmacoeconomical estimation of efficiency of different schemes of eradication therapy of Helicobacter pylori infection in children].

    PubMed

    Kashnikova, S N; Shcherbakov, P L; Kashnikov, V V; Tatarinov, P A; Shcherbakova, M Iu

    2008-01-01

    In this article farmakoekonomical analysis of efficiency of various, the most common in Russia schemes of eradication therapy disoders, associated with H. pylori infection is given to by authors basis on their private experience. All-round studying of the different economical factors influencing on a cost of used schemes is realized, and result of spent complex efficiency eradication therapy is estimated.

  5. Efficient Buffering Scheme in the LMA for Seamless Handover in PMIPv6

    NASA Astrophysics Data System (ADS)

    Kim, Kwang-Ryoul; Lee, Hyo-Beom; Choi, Hyon-Young; Min, Sung-Gi; Han, Youn-Hee

    Proxy Mobile IPv6 (PMIPv6) is proposed as a new network-based local mobility protocol which does not involve the Mobile Node (MN) in mobility management. PMIPv6, which uses link-layer attachment information, reduces the movement detection time and eliminates duplicate address detection procedures in order to provide faster handover than Mobile IPv6 (MIPv6). To eliminate packet loss during the handover period, the Local Mobility Anchor (LMA) buffering scheme is proposed. In this scheme, the LMA buffers lost packets of the Mobile Access Gateway (MAG) and the MN during the handover and recovers them after handover. A new Automatic Repeat reQuest (ARQ) handler is defined which efficiently manages the LMA buffer. The ARQ handler relays ARQ result between the MAG and the MN to the LMA. The LMA removes any buffered packets which have been successfully delivered to the MN. The ARQ handler recovers the packet loss during the handover using buffered packets in the LMA. The ARQ information, between the MAG and LMA, is inserted in the outer header of IP-in-IP encapsulated packets of a standard PMIPv6 tunnel. Since the proposed scheme simply adds information to the standard operation of an IP-in-IP tunnel between the LMA and the MAG, it can be implemented seamlessly without modification to the original PMIPv6 messages and signaling sequence. Unlike other Fast Handovers for Mobile IPv6 (FMIPv6) based enhancement for PMIPv6, the proposed scheme does not require any handover related information before the actual handover.

  6. Efficient implementation of essentially non-oscillatory shock capturing schemes

    NASA Technical Reports Server (NTRS)

    Shu, Chi-Wang; Osher, Stanley

    1987-01-01

    In the computation of discontinuous solutions of hyperbolic conservation laws, TVD (total-variation-diminishing), TVB (total-variation-bounded) and the recently developed ENO (essentially non-oscillatory) schemes have proven to be very useful. In this paper two improvements are discussed: a simple TVD Runge-Kutta type time discretization, and an ENO construction procedure based on fluxes rather than on cell averages. These improvements simplify the schemes considerably -- especially for multi-dimensional problems or problems with forcing terms. Preliminary numerical results are also given.

  7. An Efficient Scheduling Scheme on Charging Stations for Smart Transportation

    NASA Astrophysics Data System (ADS)

    Kim, Hye-Jin; Lee, Junghoon; Park, Gyung-Leen; Kang, Min-Jae; Kang, Mikyung

    This paper proposes a reservation-based scheduling scheme for the charging station to decide the service order of multiple requests, aiming at improving the satisfiability of electric vehicles. The proposed scheme makes it possible for a customer to reduce the charge cost and waiting time, while a station can extend the number of clients it can serve. A linear rank function is defined based on estimated arrival time, waiting time bound, and the amount of needed power, reducing the scheduling complexity. Receiving the requests from the clients, the power station decides the charge order by the rank function and then replies to the requesters with the waiting time and cost it can guarantee. Each requester can decide whether to charge at that station or try another station. This scheduler can evolve to integrate a new pricing policy and services, enriching the electric vehicle transport system.

  8. Wireless Instrumentation System and Power Management Scheme Therefore

    NASA Technical Reports Server (NTRS)

    Perotti, Jose (Inventor); Lucena, Angel (Inventor); Eckhoff, Anthony (Inventor); Mata, Carlos T. (Inventor); Blalock, Norman N. (Inventor); Medelius, Pedro J. (Inventor)

    2007-01-01

    A wireless instrumentation system enables a plurality of low power wireless transceivers to transmit measurement data from a plurality of remote station sensors to a central data station accurately and reliably. The system employs a relay based communications scheme where remote stations that cannot communicate directly with the central station due to interference, poor signal strength, etc., are instructed to communicate with other of the remote stations that act as relays to the central station. A unique power management scheme is also employed to minimize power usage at each remote station and thereby maximize battery life. Each of the remote stations prefembly employs a modular design to facilitate easy reconfiguration of the stations as required.

  9. On large time step TVD scheme for hyperbolic conservation laws and its efficiency evaluation

    NASA Astrophysics Data System (ADS)

    Qian, ZhanSen; Lee, Chun-Hian

    2012-08-01

    A large time step (LTS) TVD scheme originally proposed by Harten is modified and further developed in the present paper and applied to Euler equations in multidimensional problems. By firstly revealing the drawbacks of Harten's original LTS TVD scheme, and reasoning the occurrence of the spurious oscillations, a modified formulation of its characteristic transformation is proposed and a high resolution, strongly robust LTS TVD scheme is formulated. The modified scheme is proven to be capable of taking larger number of time steps than the original one. Following the modified strategy, the LTS TVD schemes for Yee's upwind TVD scheme and Yee-Roe-Davis's symmetric TVD scheme are constructed. The family of the LTS schemes is then extended to multidimensional by time splitting procedure, and the associated boundary condition treatment suitable for the LTS scheme is also imposed. The numerical experiments on Sod's shock tube problem, inviscid flows over NACA0012 airfoil and ONERA M6 wing are performed to validate the developed schemes. Computational efficiencies for the respective schemes under different CFL numbers are also evaluated and compared. The results reveal that the improvement is sizable as compared to the respective single time step schemes, especially for the CFL number ranging from 1.0 to 4.0.

  10. An Efficient and Provable Secure Revocable Identity-Based Encryption Scheme

    PubMed Central

    Wang, Changji; Li, Yuan; Xia, Xiaonan; Zheng, Kangjia

    2014-01-01

    Revocation functionality is necessary and crucial to identity-based cryptosystems. Revocable identity-based encryption (RIBE) has attracted a lot of attention in recent years, many RIBE schemes have been proposed in the literature but shown to be either insecure or inefficient. In this paper, we propose a new scalable RIBE scheme with decryption key exposure resilience by combining Lewko and Waters’ identity-based encryption scheme and complete subtree method, and prove our RIBE scheme to be semantically secure using dual system encryption methodology. Compared to existing scalable and semantically secure RIBE schemes, our proposed RIBE scheme is more efficient in term of ciphertext size, public parameters size and decryption cost at price of a little looser security reduction. To the best of our knowledge, this is the first construction of scalable and semantically secure RIBE scheme with constant size public system parameters. PMID:25238418

  11. Efficient spin injector scheme based on Heusler materials.

    PubMed

    Chadov, Stanislav; Graf, Tanja; Chadova, Kristina; Dai, Xuefang; Casper, Frederick; Fecher, Gerhard H; Felser, Claudia

    2011-07-22

    We present a rational design scheme intended to provide stable high spin polarization at the interfaces of the magnetoresistive junctions by fulfilling the criteria of structural and chemical compatibilities at the interface. This can be realized by joining the semiconducting and half-metallic Heusler materials with similar structures. The present first-principles calculations verify that the interface remains half-metallic if the nearest interface layers effectively form a stable Heusler material with the properties intermediately between the surrounding bulk parts. This leads to a simple rule for selecting the proper combinations.

  12. Low color distortion adaptive dimming scheme for power efficient LCDs

    NASA Astrophysics Data System (ADS)

    Nam, Hyoungsik; Song, Eun-Ji

    2013-06-01

    This paper demonstrates the color compensation algorithm to reduce the color distortion caused by mismatches between the reference gamma value of a dimming algorithm and the display gamma values of an LCD panel in a low power adaptive dimming scheme. In 2010, we presented the YrYgYb algorithm, which used the display gamma values extracted from the luminance data of red, green, and blue sub-pixels, Yr, Yg, and Yb, with the simulation results. It was based on the ideal panel model where the color coordinates were maintained at the fixed values over the gray levels. Whereas, this work introduces an XrYgZb color compensation algorithm which obtains the display gamma values of red, green, and blue from the different tri-stimulus data of Xr, Yg, and Zb, to obtain further reduction on the color distortion. Both simulation and measurement results ensure that a XrYgZb algorithm outperforms a previous YrYgYb algorithm. In simulation which has been conducted at the practical model derived from the measured data, the XrYgZb scheme achieves lower maximum and average color difference values of 3.7743 and 0.6230 over 24 test picture images, compared to 4.864 and 0.7156 in the YrYgYb one. In measurement of a 19-inch LCD panel, the XrYgZb method also accomplishes smaller color difference values of 1.444072 and 5.588195 over 49 combinations of red, green, and blue data, compared to 1.50578 and 6.00403 of the YrYgYb at the backlight dimming ratios of 0.85 and 0.4.

  13. An efficient and secure attribute based signcryption scheme with LSSS access structure.

    PubMed

    Hong, Hanshu; Sun, Zhixin

    2016-01-01

    Attribute based encryption (ABE) and attribute based signature (ABS) provide flexible access control with authentication for data sharing between users, but realizing both functions will bring about too much computation burden. In this paper, we combine the advantages of CP-ABE with ABS and propose a ciphertext policy attribute based signcryption scheme. In our scheme, only legal receivers can decrypt the ciphertext and verify the signature signed by data owner. Furthermore, we use linear secret sharing scheme instead of tree structure to avoid the frequent calls of recursive algorithm. By security and performance analysis, we prove that our scheme is secure as well as gains higher efficiency. PMID:27330910

  14. Power and spectrally efficient M-ARY QAM schemes for future mobile satellite communications

    NASA Technical Reports Server (NTRS)

    Sreenath, K.; Feher, K.

    1990-01-01

    An effective method to compensate nonlinear phase distortion caused by the mobile amplifier is proposed. As a first step towards the future use of spectrally efficient modulation schemes for mobile satellite applications, we have investigated effects of nonlinearities and the phase compensation method on 16-QAM. The new method provides about 2 dB savings in power for 16-QAM operation with cost effective amplifiers near saturation and thereby promising use of spectrally efficient linear modulation schemes for future mobile satellite applications.

  15. Efficient spares matrix multiplication scheme for the CYBER 203

    NASA Technical Reports Server (NTRS)

    Lambiotte, J. J., Jr.

    1984-01-01

    This work has been directed toward the development of an efficient algorithm for performing this computation on the CYBER-203. The desire to provide software which gives the user the choice between the often conflicting goals of minimizing central processing (CPU) time or storage requirements has led to a diagonal-based algorithm in which one of three types of storage is selected for each diagonal. For each storage type, an initialization sub-routine estimates the CPU and storage requirements based upon results from previously performed numerical experimentation. These requirements are adjusted by weights provided by the user which reflect the relative importance the user places on the resources. The three storage types employed were chosen to be efficient on the CYBER-203 for diagonals which are sparse, moderately sparse, or dense; however, for many densities, no diagonal type is most efficient with respect to both resource requirements. The user-supplied weights dictate the choice.

  16. Efficiency improvements of public hospitals under a capitation payment scheme.

    PubMed

    García-Lacalle, Javier; Martín, Emilio

    2013-07-01

    In a context of cost containment and demands for better quality in public health care, payment systems are used as an instrument to promote efficiency improvements in service providers. Andalusia has adopted an original type of risk-adjusted capitation payment mechanism to reimburse public hospitals. This paper presents the main characteristics of the reimbursement mechanism of the Andalusian Health Service highlighting some differences with the mechanisms adopted in other parts of Europe. The paper also explores the evolution of the efficiency and quality of the hospitals after its implementation using the Malmquist index. Results indicate that hospitals have slightly improved their efficiency, particularly urban hospitals, and these improvements are not significantly related to a negative evolution of quality. However, it is not possible to assert to what extent, improvements are the consequence of the new payment system. The organisation of the Servicio Andaluz de Salud and the limited competition between hospitals reduce the effectiveness of the reform. PMID:23343663

  17. A privacy preserving secure and efficient authentication scheme for telecare medical information systems.

    PubMed

    Mishra, Raghavendra; Barnwal, Amit Kumar

    2015-05-01

    The Telecare medical information system (TMIS) presents effective healthcare delivery services by employing information and communication technologies. The emerging privacy and security are always a matter of great concern in TMIS. Recently, Chen at al. presented a password based authentication schemes to address the privacy and security. Later on, it is proved insecure against various active and passive attacks. To erase the drawbacks of Chen et al.'s anonymous authentication scheme, several password based authentication schemes have been proposed using public key cryptosystem. However, most of them do not present pre-smart card authentication which leads to inefficient login and password change phases. To present an authentication scheme with pre-smart card authentication, we present an improved anonymous smart card based authentication scheme for TMIS. The proposed scheme protects user anonymity and satisfies all the desirable security attributes. Moreover, the proposed scheme presents efficient login and password change phases where incorrect input can be quickly detected and a user can freely change his password without server assistance. Moreover, we demonstrate the validity of the proposed scheme by utilizing the widely-accepted BAN (Burrows, Abadi, and Needham) logic. The proposed scheme is also comparable in terms of computational overheads with relevant schemes. PMID:25750176

  18. Optimum management scheme to control nonpoint pollution in Korea.

    PubMed

    Hwang, D-H; Choi, J-Y

    2007-01-01

    Comprehensive measures to control nonpoint source were developed by the Office of the Prime Minister, Korea in March 2004. These management measures present the government's policies and directions relating to nonpoint source management by 2020. However, the government has encountered difficulties since the government implemented such policies without preparing legal and institutional arrangements associated with nonpoint source management practices. Particularly, there was no legal system to manage the workplaces and construction sites that discharge the polluted runoff. To provide legal arrangements to achieve efficient implementation of the government's nonpoint source management policies, amendments to the "Water Quality Preservation Act" were proposed in the congress in March 2005 and took effect from April 2006. Subsequently, the nationally mandated nonpoint source control system was to be applied to such industries and construction sites. This paper attempts to propose the scope of the nonpoint source control system and effective strategies applied to the construction sites and industrial workplaces in Korea.

  19. A scheme for efficient quantum computation with linear optics

    NASA Astrophysics Data System (ADS)

    Knill, E.; Laflamme, R.; Milburn, G. J.

    2001-01-01

    Quantum computers promise to increase greatly the efficiency of solving problems such as factoring large integers, combinatorial optimization and quantum physics simulation. One of the greatest challenges now is to implement the basic quantum-computational elements in a physical system and to demonstrate that they can be reliably and scalably controlled. One of the earliest proposals for quantum computation is based on implementing a quantum bit with two optical modes containing one photon. The proposal is appealing because of the ease with which photon interference can be observed. Until now, it suffered from the requirement for non-linear couplings between optical modes containing few photons. Here we show that efficient quantum computation is possible using only beam splitters, phase shifters, single photon sources and photo-detectors. Our methods exploit feedback from photo-detectors and are robust against errors from photon loss and detector inefficiency. The basic elements are accessible to experimental investigation with current technology.

  20. Design and Analysis of a Dynamic Mobility Management Scheme for Wireless Mesh Network

    PubMed Central

    Roy, Sudipta

    2013-01-01

    Seamless mobility management of the mesh clients (MCs) in wireless mesh network (WMN) has drawn a lot of attention from the research community. A number of mobility management schemes such as mesh network with mobility management (MEMO), mesh mobility management (M3), and wireless mesh mobility management (WMM) have been proposed. The common problem with these schemes is that they impose uniform criteria on all the MCs for sending route update message irrespective of their distinct characteristics. This paper proposes a session-to-mobility ratio (SMR) based dynamic mobility management scheme for handling both internet and intranet traffic. To reduce the total communication cost, this scheme considers each MC's session and mobility characteristics by dynamically determining optimal threshold SMR value for each MC. A numerical analysis of the proposed scheme has been carried out. Comparison with other schemes shows that the proposed scheme outperforms MEMO, M3, and WMM with respect to total cost. PMID:24311982

  1. Suitable scheme study of Chinese Building Energy Efficiency CDM Projects

    NASA Astrophysics Data System (ADS)

    Huang, Beijia; Yang, Haizhen; Wang, Shaoping; Wang, Feng

    2010-11-01

    China has great potential to develop Building Energy Efficiency Clean Development Mechanism (BEE CDM) projects, although have many challenges. Our results show that large-scale public buildings and urban residential buildings have relatively high BEE CDM potential, when comparing their characteristics to the CDM project requirements. The building enclosure, illumination energy conservation, air condition energy saving, solar thermal, and solar photovoltaic technology have relatively high application potential while considering the energy saving potential and marginal emission reduction cost. Case study of large-scale buildings shows that technology integration of building enclosure, illumination energy conservation, air condition energy saving, solar thermal can reduce required building number to 130 in order to meet the 1×105 tCO2 e/a reduction criteria. Some suggestions are also given in this paper.

  2. From generic scheme to brand-generic scheme: Have new policy influenced the efficiency of Iranian pharmaceutical companies?

    PubMed Central

    Hashemi-Meshkini, Amir; Varmaghani, Mehdi; Yousefi, Mehdi; Yaghoubifard, Saeed; Zekri, Hedieh-Sadat; Nikfar, Shekoufeh; Kebriaeezadeh, Abbas

    2014-01-01

    Objective: Brand-generic scheme was implemented in Iran to improve the competition in the pharmaceutical market. In this study, we aim to assess if this policy had any positive effect on efficiency of Iranian pharmaceutical companies. Methods: We used data envelopment analysis to evaluate the relative efficiency of pharmaceutical companies during 1999-2008. The Wilcoxon matched-pairs signed-rank and sign tests were used to assess the difference between mean technical efficiency of companies before and after implementation of the new policy. Findings: Although the Wilcoxon matched-pairs signed-rank tests did not show any significant differences in favor of the new policy in terms of both relative and pure (managerial) technical efficiency for included companies (P = 0.079 and 0.07, respectively), but the one-sided sign test indicated that only relative pure (managerial) efficiency has been improved after this policy (P = 0.031). Conclusion: The “brand-generic scheme” does not seem to be a successful policy to improve efficiency level and prompt competition in pharmaceutical companies in Iran. To achieve this aim, consideration of infrastructural requirements including transparent and non-discriminating laws and regulations to support competition, the competitive pricing policies, the presence of international companies in the market, and full privatization of companies had to be also deeming by policy makers. PMID:25328898

  3. Regulation control and energy management scheme for wireless power transfer

    SciTech Connect

    Miller, John M.

    2015-12-29

    Power transfer rate at a charging facility can be maximized by employing a feedback scheme. The state of charge (SOC) and temperature of the regenerative energy storage system (RESS) pack of a vehicle is monitored to determine the load due to the RESS pack. An optimal frequency that cancels the imaginary component of the input impedance for the output signal from a grid converter is calculated from the load of the RESS pack, and a frequency offset f* is made to the nominal frequency f.sub.0 of the grid converter output based on the resonance frequency of a magnetically coupled circuit. The optimal frequency can maximize the efficiency of the power transfer. Further, an optimal grid converter duty ratio d* can be derived from the charge rate of the RESS pack. The grid converter duty ratio d* regulates wireless power transfer (WPT) power level.

  4. Proposed CMG momentum management scheme for space station

    NASA Technical Reports Server (NTRS)

    Bishop, L. R.; Bishop, R. H.; Lindsay, K. L.

    1987-01-01

    A discrete control moment gyro (CMG) momentum management scheme (MMS) applicable to spacecraft with principal axes misalignments, such as the proposed NASA dual keel space station, is presented in this paper. The objective of the MMS is to minmize CMG angular momentum storage requirements for maintaining the space station near local vertical in the presence of environmental disturbances. It utilizes available environmental disturbances, namely gravity gradient torques, to minimize CMG momentum storage. The MMS is executed once per orbit and generates a commanded torque equilibrium attitude (TEA) time history which consists of a yaw, pitch and roll angle command profile. Although the algorithm is called only once per orbit to compute the TEA profile, the space station will maneuver several discrete times each orbit.

  5. Development of an estuarine assessment scheme for the management of a highly urbanised catchment/estuary system, Sydney estuary, Australia.

    PubMed

    Birch, G F; Gunns, T J; Chapman, D; Harrison, D

    2016-05-01

    As coastal populations increase, considerable pressures are exerted on estuarine environments. Recently, there has been a trend towards the development and use of estuarine assessment schemes as a decision support tool in the management of these environments. These schemes offer a method by which complex environmental data is converted into a readily understandable and communicable format for informed decision making and effective distribution of limited management resources. Reliability and effectiveness of these schemes are often limited due to a complex assessment framework, poor data management and use of ineffective environmental indicators. The current scheme aims to improve reliability in the reporting of estuarine condition by including a concise assessment framework, employing high-value indicators and, in a unique approach, employing fuzzy logic in indicator evaluation. Using Sydney estuary as a case study, each of the 15 sub-catchment/sub-estuary systems were assessed using the current scheme. Results identified that poor sediment quality was a significant issue in Blackwattle/Rozelle Bay, Iron Cove and Hen and Chicken Bay while poor water quality was of particular concern in Duck River, Homebush Bay and the Parramatta River. Overall results of the assessment scheme were used to prioritise the management of each sub-catchment/sub-estuary assessed with Blackwattle/Rozelle Bay, Homebush Bay, Iron Cove and Duck River considered to be in need of a high priority management response. A report card format, using letter grades, was employed to convey the results of the assessment in a readily understood manner to estuarine managers and members of the public. Letter grades also provide benchmarking and performance monitoring ability, allowing estuarine managers to set improvement targets and assesses the effectiveness of management strategies. The current assessment scheme provides an effective, integrated and consistent assessment of estuarine health and

  6. A Security-Awareness Virtual Machine Management Scheme Based on Chinese Wall Policy in Cloud Computing

    PubMed Central

    Gui, Xiaolin; Lin, Jiancai; Tian, Feng; Zhao, Jianqiang; Dai, Min

    2014-01-01

    Cloud computing gets increasing attention for its capacity to leverage developers from infrastructure management tasks. However, recent works reveal that side channel attacks can lead to privacy leakage in the cloud. Enhancing isolation between users is an effective solution to eliminate the attack. In this paper, to eliminate side channel attacks, we investigate the isolation enhancement scheme from the aspect of virtual machine (VM) management. The security-awareness VMs management scheme (SVMS), a VMs isolation enhancement scheme to defend against side channel attacks, is proposed. First, we use the aggressive conflict of interest relation (ACIR) and aggressive in ally with relation (AIAR) to describe user constraint relations. Second, based on the Chinese wall policy, we put forward four isolation rules. Third, the VMs placement and migration algorithms are designed to enforce VMs isolation between the conflict users. Finally, based on the normal distribution, we conduct a series of experiments to evaluate SVMS. The experimental results show that SVMS is efficient in guaranteeing isolation between VMs owned by conflict users, while the resource utilization rate decreases but not by much. PMID:24688434

  7. Analysis of Two-Phase Path Management Scheme for MPLS Traffic Engineering

    NASA Astrophysics Data System (ADS)

    Tamura, Hitomi; Kawahara, Kenji; Oie, Yuji

    Traffic Engineering (TE) is important for improving QoS in forwarding paths by efficient use of network resources. In fact, MPLS allows several detour paths to be (pre-)established for some source-destination pair as well as its primary path of minimum hops. Thus, we focus on a two-phase path management scheme using these two kinds of paths. In the first phase, each primary path is allocated to a flow on a specific source-destination pair if the path is not congested, i.e., if its utilization is less than some predetermined threshold; otherwise, as the second phase, one of the detour paths is allocated randomly if the path is available. Therefore, in this paper, we analytically evaluate this path management scheme by extending the M/M/c/c queueing system, and through some numerical results we investigate the impact of a threshold on the flow-blocking probability. Through some numerical results, we discuss the adequacy of the path management scheme for MPLS-TE.

  8. A Novel Scheme for an Energy Efficient Internet of Things Based on Wireless Sensor Networks.

    PubMed

    Rani, Shalli; Talwar, Rajneesh; Malhotra, Jyoteesh; Ahmed, Syed Hassan; Sarkar, Mahasweta; Song, Houbing

    2015-01-01

    One of the emerging networking standards that gap between the physical world and the cyber one is the Internet of Things. In the Internet of Things, smart objects communicate with each other, data are gathered and certain requests of users are satisfied by different queried data. The development of energy efficient schemes for the IoT is a challenging issue as the IoT becomes more complex due to its large scale the current techniques of wireless sensor networks cannot be applied directly to the IoT. To achieve the green networked IoT, this paper addresses energy efficiency issues by proposing a novel deployment scheme. This scheme, introduces: (1) a hierarchical network design; (2) a model for the energy efficient IoT; (3) a minimum energy consumption transmission algorithm to implement the optimal model. The simulation results show that the new scheme is more energy efficient and flexible than traditional WSN schemes and consequently it can be implemented for efficient communication in the IoT. PMID:26569260

  9. A Novel Scheme for an Energy Efficient Internet of Things Based on Wireless Sensor Networks.

    PubMed

    Rani, Shalli; Talwar, Rajneesh; Malhotra, Jyoteesh; Ahmed, Syed Hassan; Sarkar, Mahasweta; Song, Houbing

    2015-11-12

    One of the emerging networking standards that gap between the physical world and the cyber one is the Internet of Things. In the Internet of Things, smart objects communicate with each other, data are gathered and certain requests of users are satisfied by different queried data. The development of energy efficient schemes for the IoT is a challenging issue as the IoT becomes more complex due to its large scale the current techniques of wireless sensor networks cannot be applied directly to the IoT. To achieve the green networked IoT, this paper addresses energy efficiency issues by proposing a novel deployment scheme. This scheme, introduces: (1) a hierarchical network design; (2) a model for the energy efficient IoT; (3) a minimum energy consumption transmission algorithm to implement the optimal model. The simulation results show that the new scheme is more energy efficient and flexible than traditional WSN schemes and consequently it can be implemented for efficient communication in the IoT.

  10. A Novel Scheme for an Energy Efficient Internet of Things Based on Wireless Sensor Networks

    PubMed Central

    Rani, Shalli; Talwar, Rajneesh; Malhotra, Jyoteesh; Ahmed, Syed Hassan; Sarkar, Mahasweta; Song, Houbing

    2015-01-01

    One of the emerging networking standards that gap between the physical world and the cyber one is the Internet of Things. In the Internet of Things, smart objects communicate with each other, data are gathered and certain requests of users are satisfied by different queried data. The development of energy efficient schemes for the IoT is a challenging issue as the IoT becomes more complex due to its large scale the current techniques of wireless sensor networks cannot be applied directly to the IoT. To achieve the green networked IoT, this paper addresses energy efficiency issues by proposing a novel deployment scheme. This scheme, introduces: (1) a hierarchical network design; (2) a model for the energy efficient IoT; (3) a minimum energy consumption transmission algorithm to implement the optimal model. The simulation results show that the new scheme is more energy efficient and flexible than traditional WSN schemes and consequently it can be implemented for efficient communication in the IoT. PMID:26569260

  11. Efficient asymmetric image authentication schemes based on photon counting-double random phase encoding and RSA algorithms.

    PubMed

    Moon, Inkyu; Yi, Faliu; Han, Mingu; Lee, Jieun

    2016-06-01

    Recently, double random phase encoding (DRPE) has been integrated with the photon counting (PC) imaging technique for the purpose of secure image authentication. In this scheme, the same key should be securely distributed and shared between the sender and receiver, but this is one of the most vexing problems of symmetric cryptosystems. In this study, we propose an efficient asymmetric image authentication scheme by combining the PC-DRPE and RSA algorithms, which solves key management and distribution problems. The retrieved image from the proposed authentication method contains photon-limited encrypted data obtained by means of PC-DRPE. Therefore, the original image can be protected while the retrieved image can be efficiently verified using a statistical nonlinear correlation approach. Experimental results demonstrate the feasibility of our proposed asymmetric image authentication method.

  12. Efficient asymmetric image authentication schemes based on photon counting-double random phase encoding and RSA algorithms.

    PubMed

    Moon, Inkyu; Yi, Faliu; Han, Mingu; Lee, Jieun

    2016-06-01

    Recently, double random phase encoding (DRPE) has been integrated with the photon counting (PC) imaging technique for the purpose of secure image authentication. In this scheme, the same key should be securely distributed and shared between the sender and receiver, but this is one of the most vexing problems of symmetric cryptosystems. In this study, we propose an efficient asymmetric image authentication scheme by combining the PC-DRPE and RSA algorithms, which solves key management and distribution problems. The retrieved image from the proposed authentication method contains photon-limited encrypted data obtained by means of PC-DRPE. Therefore, the original image can be protected while the retrieved image can be efficiently verified using a statistical nonlinear correlation approach. Experimental results demonstrate the feasibility of our proposed asymmetric image authentication method. PMID:27411183

  13. A HIPAA-compliant key management scheme with revocation of authorization.

    PubMed

    Lee, Wei-Bin; Lee, Chien-Ding; Ho, Kevin I-J

    2014-03-01

    Patient control over electronic protected health information (ePHI) is one of the major concerns in the Health Insurance and Accountability Act (HIPAA). In this paper, a new key management scheme is proposed to facilitate control by providing two functionalities. First, a patient can authorize more than one healthcare institute within a designated time period to access his or her ePHIs. Second, a patient can revoke authorization and add new authorized institutes at any time as necessary. In the design, it is not required to re-encrypt ePHIs for adding and revoking authorizations, and the implementation is time- and cost-efficient. Consent exception is also considered by the proposed scheme. PMID:24480372

  14. A new computational scheme for the Dirac-Hartree-Fock method employing an efficient integral algorithm

    NASA Astrophysics Data System (ADS)

    Yanai, Takeshi; Nakajima, Takahito; Ishikawa, Yasuyuki; Hirao, Kimihiko

    2001-04-01

    A highly efficient computational scheme for four-component relativistic ab initio molecular orbital (MO) calculations over generally contracted spherical harmonic Gaussian-type spinors (GTSs) is presented. Benchmark calculations for the ground states of the group IB hydrides, MH, and dimers, M2 (M=Cu, Ag, and Au), by the Dirac-Hartree-Fock (DHF) method were performed with a new four-component relativistic ab initio MO program package oriented toward contracted GTSs. The relativistic electron repulsion integrals (ERIs), the major bottleneck in routine DHF calculations, are calculated efficiently employing the fast ERI routine SPHERICA, exploiting the general contraction scheme, and the accompanying coordinate expansion method developed by Ishida. Illustrative calculations clearly show the efficiency of our computational scheme.

  15. Designing Pay-As-You-Throw schemes in municipal waste management services: A holistic approach

    SciTech Connect

    Elia, Valerio; Gnoni, Maria Grazia Tornese, Fabiana

    2015-10-15

    Highlights: • Pay-As-You-Throw (PAYT) schemes are becoming widespread in several countries. • Economic, organizational and technological issues have to be integrated in an efficient PAYT model design. • Efficiency refers to a PAYT system which support high citizen participation rates as well as economic sustainability. • Different steps and constraints have to be evaluated from collection services to type technologies. • An holistic approach is discussed to support PAYT systems diffusion. - Abstract: Pay-As-You-Throw (PAYT) strategies are becoming widely applied in solid waste management systems; the main purpose is to support a more sustainable – from economic, environmental and social points of view – management of waste flows. Adopting PAYT charging models increases the complexity level of the waste management service as new organizational issues have to be evaluated compared to flat charging models. In addition, innovative technological solutions could also be adopted to increase the overall efficiency of the service. Unit pricing, user identification and waste measurement represent the three most important processes to be defined in a PAYT system. The paper proposes a holistic framework to support an effective design and management process. The framework defines most critical processes and effective organizational and technological solutions for supporting waste managers as well as researchers.

  16. A solution accurate, efficient and stable unsplit staggered mesh scheme for three dimensional magnetohydrodynamics

    NASA Astrophysics Data System (ADS)

    Lee, Dongwook

    2013-06-01

    In this paper, we extend the unsplit staggered mesh scheme (USM) for 2D magnetohydrodynamics (MHD) [D. Lee, A.E. Deane, An unsplit staggered mesh scheme for multidimensional magnetohydrodynamics, J. Comput. Phys. 228 (2009) 952-975] to a full 3D MHD scheme. The scheme is a finite-volume Godunov method consisting of a constrained transport (CT) method and an efficient and accurate single-step, directionally unsplit multidimensional data reconstruction-evolution algorithm, which extends Colella's original 2D corner transport upwind (CTU) method [P. Colella, Multidimensional upwind methods for hyperbolic conservation laws, J. Comput. Phys. 87 (1990) 446-466]. We present two types of data reconstruction-evolution algorithms for 3D: (1) a reduced CTU scheme and (2) a full CTU scheme. The reduced 3D CTU scheme is a variant of a simple 3D extension of Collela's 2D CTU method and is considered as a direct extension from the 2D USM scheme. The full 3D CTU scheme is our primary 3D solver which includes all multidimensional cross-derivative terms for stability. The latter method is logically analogous to the 3D unsplit CTU method by Saltzman [J. Saltzman, An unsplit 3D upwind method for hyperbolic conservation laws, J. Comput. Phys. 115 (1994) 153-168]. The major novelties in our algorithms are twofold. First, we extend the reduced CTU scheme to the full CTU scheme which is able to run with CFL numbers close to unity. Both methods utilize the transverse update technique developed in the 2D USM algorithm to account for transverse fluxes without solving intermediate Riemann problems, which in turn gives cost-effective 3D methods by reducing the total number of Riemann solves. The proposed algorithms are simple and efficient especially when including multidimensional MHD terms that maintain in-plane magnetic field dynamics. Second, we introduce a new CT scheme that makes use of proper upwind information in taking averages of electric fields. Our 3D USM schemes can be easily

  17. Highly efficient light management for perovskite solar cells

    PubMed Central

    Wang, Dong-Lin; Cui, Hui-Juan; Hou, Guo-Jiao; Zhu, Zhen-Gang; Yan, Qing-Bo; Su, Gang

    2016-01-01

    Organic-inorganic halide perovskite solar cells have enormous potential to impact the existing photovoltaic industry. As realizing a higher conversion efficiency of the solar cell is still the most crucial task, a great number of schemes were proposed to minimize the carrier loss by optimizing the electrical properties of the perovskite solar cells. Here, we focus on another significant aspect that is to minimize the light loss by optimizing the light management to gain a high efficiency for perovskite solar cells. In our scheme, the slotted and inverted prism structured SiO2 layers are adopted to trap more light into the solar cells, and a better transparent conducting oxide layer is employed to reduce the parasitic absorption. For such an implementation, the efficiency and the serviceable angle of the perovskite solar cell can be promoted impressively. This proposal would shed new light on developing the high-performance perovskite solar cells. PMID:26733112

  18. Highly efficient light management for perovskite solar cells.

    PubMed

    Wang, Dong-Lin; Cui, Hui-Juan; Hou, Guo-Jiao; Zhu, Zhen-Gang; Yan, Qing-Bo; Su, Gang

    2016-01-06

    Organic-inorganic halide perovskite solar cells have enormous potential to impact the existing photovoltaic industry. As realizing a higher conversion efficiency of the solar cell is still the most crucial task, a great number of schemes were proposed to minimize the carrier loss by optimizing the electrical properties of the perovskite solar cells. Here, we focus on another significant aspect that is to minimize the light loss by optimizing the light management to gain a high efficiency for perovskite solar cells. In our scheme, the slotted and inverted prism structured SiO2 layers are adopted to trap more light into the solar cells, and a better transparent conducting oxide layer is employed to reduce the parasitic absorption. For such an implementation, the efficiency and the serviceable angle of the perovskite solar cell can be promoted impressively. This proposal would shed new light on developing the high-performance perovskite solar cells.

  19. Efficient Anonymous Authentication Protocol Using Key-Insulated Signature Scheme for Secure VANET

    NASA Astrophysics Data System (ADS)

    Park, Youngho; Sur, Chul; Jung, Chae Duk; Rhee, Kyung-Hyune

    In this paper, we propose an efficient authentication protocol with conditional privacy preservation for secure vehicular communications. The proposed protocol follows the system model to issue on-the-fly anonymous public key certificates to vehicles by road-side units. In order to design an efficient message authentication protocol, we consider a key-insulated signature scheme for certifying anonymous public keys of vehicles to such a system model. We demonstrate experimental results to confirm that the proposed protocol has better performance than other protocols based on group signature schemes.

  20. An Efficient Perturbed Parameter Scheme in the Lorenz System for Quantifying Model Uncertainty

    NASA Astrophysics Data System (ADS)

    Chen, G.; Kirtman, B. P.; Iskandarani, M.

    2014-12-01

    Our goal is to develop a reliable and efficient perturbed parameter scheme comparable to stochastic parameterization schemes. The Lorenz model is a simple testbed for numerical simulations. We used a two time-scale Lorenz 63 (L63) model to mimic the ocean-atmosphere coupled system and a Lorenz 96 (L96) model coupled to the atmospheric component representing a small-scale spatially resolved system. The full set of equations is defined as the "truth". The spatially resolved system will be bulk-parameterized by three different schemes: (i) deterministic, (ii) stochastic parameterization , and (iii) perturbed parameter. Perfect initial conditions are applied to investigate pure model error. Although stochastic parameterizations have been proven to resolve systematic errors, they become computationally expensive as the stochastic dimension increases. We propose to apply "informative" probability distributions for the perturbed parameter scheme to resolve systematic bias where previous research have failed to do so. The proposed scheme uses a stochastic spectral method, Polynomial Chaos Expansion (PCE), to reduce model runs while achieving fast convergence to the exact solution. PCE is implemented as an efficient "surrogate" model to generate a large ensemble. The PCE-accelerated informative perturbed parameter scheme generated competitive and reliable ensemble forecasts.

  1. Approaches of Improving University Assets Management Efficiency

    ERIC Educational Resources Information Center

    Wang, Jingliang

    2015-01-01

    University assets management, as an important content of modern university management, is generally confronted with the issue of low efficiency. Currently, to address the problems exposed in university assets management and take appropriate modification measures is an urgent issue in front of Chinese university assets management sectors. In this…

  2. An efficient forward-secure group certificate digital signature scheme to enhance EMR authentication process.

    PubMed

    Yu, Yao-Chang; Hou, Ting-Wei

    2014-05-01

    The frequently used digital signature algorithms, such as RSA and the Digital Signature Algorithm (DSA), lack forward-secure function. The result is that, when private keys are renewed, trustworthiness is lost. In other words, electronic medical records (EMRs) signed by revoked private keys are no longer trusted. This significant security threat stands in the way of EMR adoption. This paper proposes an efficient forward-secure group certificate digital signature scheme that is based on Shamir's (t,n) threshold scheme and Schnorr's digital signature scheme to ensure trustworthiness is maintained when private keys are renewed and to increase the efficiency of EMRs' authentication processes in terms of number of certificates, number of keys, forward-secure ability and searching time.

  3. An Energy-Efficient Game-Theory-Based Spectrum Decision Scheme for Cognitive Radio Sensor Networks.

    PubMed

    Salim, Shelly; Moh, Sangman

    2016-01-01

    A cognitive radio sensor network (CRSN) is a wireless sensor network in which sensor nodes are equipped with cognitive radio. In this paper, we propose an energy-efficient game-theory-based spectrum decision (EGSD) scheme for CRSNs to prolong the network lifetime. Note that energy efficiency is the most important design consideration in CRSNs because it determines the network lifetime. The central part of the EGSD scheme consists of two spectrum selection algorithms: random selection and game-theory-based selection. The EGSD scheme also includes a clustering algorithm, spectrum characterization with a Markov chain, and cluster member coordination. Our performance study shows that EGSD outperforms the existing popular framework in terms of network lifetime and coordination overhead. PMID:27376290

  4. An Energy-Efficient Game-Theory-Based Spectrum Decision Scheme for Cognitive Radio Sensor Networks

    PubMed Central

    Salim, Shelly; Moh, Sangman

    2016-01-01

    A cognitive radio sensor network (CRSN) is a wireless sensor network in which sensor nodes are equipped with cognitive radio. In this paper, we propose an energy-efficient game-theory-based spectrum decision (EGSD) scheme for CRSNs to prolong the network lifetime. Note that energy efficiency is the most important design consideration in CRSNs because it determines the network lifetime. The central part of the EGSD scheme consists of two spectrum selection algorithms: random selection and game-theory-based selection. The EGSD scheme also includes a clustering algorithm, spectrum characterization with a Markov chain, and cluster member coordination. Our performance study shows that EGSD outperforms the existing popular framework in terms of network lifetime and coordination overhead. PMID:27376290

  5. An efficient and provably-secure certificateless public key encryption scheme for telecare medicine information systems.

    PubMed

    Guo, Rui; Wen, Qiaoyan; Shi, Huixian; Jin, Zhengping; Zhang, Hua

    2013-10-01

    Telecare Medicine Information Systems (TMIS) promote the traditional medical and healthcare services by information and communication technology. Since the physician and caregiver can monitor the patient's physiological condition remotely in TMIS, the confidentiality of this sensitive data should be protected, which is the key issue in the Health Insurance Portability and Accountability Act. In this paper, we propose an efficient certificateless public key encryption scheme without bilinear pairing for TMIS. Our proposal is proved to be secure in the random oracle model under the hardness assumption of computational Diffie-Hellman problem. Moreover, after modifying the original model of the certificateless encryption, this scheme achieves Girault's trust level 3. Compared with the related protocols, the perform evaluations show that our scheme is more efficient and appropriate to collocate with low power mobile devices for TMIS.

  6. An Energy-Efficient Game-Theory-Based Spectrum Decision Scheme for Cognitive Radio Sensor Networks.

    PubMed

    Salim, Shelly; Moh, Sangman

    2016-06-30

    A cognitive radio sensor network (CRSN) is a wireless sensor network in which sensor nodes are equipped with cognitive radio. In this paper, we propose an energy-efficient game-theory-based spectrum decision (EGSD) scheme for CRSNs to prolong the network lifetime. Note that energy efficiency is the most important design consideration in CRSNs because it determines the network lifetime. The central part of the EGSD scheme consists of two spectrum selection algorithms: random selection and game-theory-based selection. The EGSD scheme also includes a clustering algorithm, spectrum characterization with a Markov chain, and cluster member coordination. Our performance study shows that EGSD outperforms the existing popular framework in terms of network lifetime and coordination overhead.

  7. Smart LED allocation scheme for efficient multiuser visible light communication networks.

    PubMed

    Sewaiwar, Atul; Tiwari, Samrat Vikramaditya; Chung, Yeon Ho

    2015-05-18

    In a multiuser bidirectional visible light communication (VLC), a large number of LEDs or an LED array needs to be allocated in an efficient manner to ensure sustainable data rate and link quality. Moreover, in order to support an increasing or decreasing number of users in the network, the LED allocation is required to be performed dynamically. In this paper, a novel smart LED allocation scheme for efficient multiuser VLC networks is presented. The proposed scheme allocates RGB LEDs to multiple users in a dynamic and efficient fashion, while satisfying illumination requirements in an indoor environment. The smart LED array comprised of RGB LEDs is divided into sectors according to the location of the users. The allocated sectors then provide optical power concentration toward the users for efficient and reliable data transmission. An algorithm for the dynamic allocation of the LEDs is also presented. To verify its effective resource allocation feature of the proposed scheme, simulations were performed. It is found that the proposed smart LED allocation scheme provides the effect of optical beamforming toward individual users, thereby increasing the collective power concentration of the optical signals on the desirable users and resulting in significantly increased data rate, while ensuring sufficient illumination in a multiuser VLC environment.

  8. Simulation of rapidly varying flow using an efficient TVD-MacCormack scheme

    NASA Astrophysics Data System (ADS)

    Liang, Dongfang; Lin, Binliang; Falconer, Roger A.

    2007-02-01

    An efficient numerical scheme is outlined for solving the SWEs (shallow water equations) in environmental flow; this scheme includes the addition of a five-point symmetric total variation diminishing (TVD) term to the corrector step of the standard MacCormack scheme. The paper shows that the discretization of the conservative and non-conservative forms of the SWEs leads to the same finite difference scheme when the source term is discretized in a certain way. The non-conservative form is used in the solution outlined herein, since this formulation is simpler and more efficient. The time step is determined adaptively, based on the maximum instantaneous Courant number across the domain. The bed friction is included either explicitly or implicitly in the computational algorithm according to the local water depth. The wetting and drying process is simulated in a manner which complements the use of operator-splitting and two-stage numerical schemes. The numerical model was then applied to a hypothetical dam-break scenario, an experimental dam-break case and an extreme flooding event over the Toce River valley physical model. The predicted results are free of spurious oscillations for both sub- and super-critical flows, and the predictions compare favourably with the experimental measurements.

  9. An Energy Efficient Mutual Authentication and Key Agreement Scheme Preserving Anonymity for Wireless Sensor Networks

    PubMed Central

    Lu, Yanrong; Li, Lixiang; Peng, Haipeng; Yang, Yixian

    2016-01-01

    WSNs (Wireless sensor networks) are nowadays viewed as a vital portion of the IoTs (Internet of Things). Security is a significant issue in WSNs, especially in resource-constrained environments. AKA (Authentication and key agreement) enhances the security of WSNs against adversaries attempting to get sensitive sensor data. Various AKA schemes have been developed for verifying the legitimate users of a WSN. Firstly, we scrutinize Amin-Biswas’s currently scheme and demonstrate the major security loopholes in their works. Next, we propose a lightweight AKA scheme, using symmetric key cryptography based on smart card, which is resilient against all well known security attacks. Furthermore, we prove the scheme accomplishes mutual handshake and session key agreement property securely between the participates involved under BAN (Burrows, Abadi and Needham) logic. Moreover, formal security analysis and simulations are also conducted using AVISPA(Automated Validation of Internet Security Protocols and Applications) to show that our scheme is secure against active and passive attacks. Additionally, performance analysis shows that our proposed scheme is secure and efficient to apply for resource-constrained WSNs. PMID:27338382

  10. An Energy Efficient Mutual Authentication and Key Agreement Scheme Preserving Anonymity for Wireless Sensor Networks.

    PubMed

    Lu, Yanrong; Li, Lixiang; Peng, Haipeng; Yang, Yixian

    2016-01-01

    WSNs (Wireless sensor networks) are nowadays viewed as a vital portion of the IoTs (Internet of Things). Security is a significant issue in WSNs, especially in resource-constrained environments. AKA (Authentication and key agreement) enhances the security of WSNs against adversaries attempting to get sensitive sensor data. Various AKA schemes have been developed for verifying the legitimate users of a WSN. Firstly, we scrutinize Amin-Biswas's currently scheme and demonstrate the major security loopholes in their works. Next, we propose a lightweight AKA scheme, using symmetric key cryptography based on smart card, which is resilient against all well known security attacks. Furthermore, we prove the scheme accomplishes mutual handshake and session key agreement property securely between the participates involved under BAN (Burrows, Abadi and Needham) logic. Moreover, formal security analysis and simulations are also conducted using AVISPA(Automated Validation of Internet Security Protocols and Applications) to show that our scheme is secure against active and passive attacks. Additionally, performance analysis shows that our proposed scheme is secure and efficient to apply for resource-constrained WSNs. PMID:27338382

  11. Efficiency Management in Spaceflight Systems

    NASA Technical Reports Server (NTRS)

    Murphy, Karen

    2016-01-01

    Efficiency in spaceflight is often approached as “faster, better, cheaper – pick two”. The high levels of performance and reliability required for each mission suggest that planners can only control for two of the three. True efficiency comes by optimizing a system across all three parameters. The functional processes of spaceflight become technical requirements on three operational groups during mission planning: payload, vehicle, and launch operations. Given the interrelationships among the functions performed by the operational groups, optimizing function resources from one operational group to the others affects the efficiency of those groups and therefore the mission overall. This paper helps outline this framework and creates a context in which to understand the effects of resource trades on the overall system, improving the efficiency of the operational groups and the mission as a whole. This allows insight into and optimization of the controlling factors earlier in the mission planning stage.

  12. Efficiency Management in Spaceflight Systems

    NASA Technical Reports Server (NTRS)

    Murphy, Karen

    2016-01-01

    Efficiency in spaceflight is often approached as "faster, better, cheaper - pick two". The high levels of performance and reliability required for each mission suggest that planners can only control for two of the three. True efficiency comes by optimizing a system across all three parameters. The functional processes of spaceflight become technical requirements on three operational groups during mission planning: payload, vehicle, and launch operations. Given the interrelationships among the functions performed by the operational groups, optimizing function resources from one operational group to the others affects the efficiency of those groups and therefore the mission overall. This paper helps outline this framework and creates a context in which to understand the effects of resource trades on the overall system, improving the efficiency of the operational groups and the mission as a whole. This allows insight into and optimization of the controlling factors earlier in the mission planning stage.

  13. A High Efficiency Boost Converter with MPPT Scheme for Low Voltage Thermoelectric Energy Harvesting

    NASA Astrophysics Data System (ADS)

    Guan, Mingjie; Wang, Kunpeng; Zhu, Qingyuan; Liao, Wei-Hsin

    2016-11-01

    Using thermoelectric elements to harvest energy from heat has been of great interest during the last decade. This paper presents a direct current-direct current (DC-DC) boost converter with a maximum power point tracking (MPPT) scheme for low input voltage thermoelectric energy harvesting applications. Zero current switch technique is applied in the proposed MPPT scheme. Theoretical analysis on the converter circuits is explored to derive the equations for parameters needed in the design of the boost converter. Simulations and experiments are carried out to verify the theoretical analysis and equations. A prototype of the designed converter is built using discrete components and a low-power microcontroller. The results show that the designed converter can achieve a high efficiency at low input voltage. The experimental efficiency of the designed converter is compared with a commercial converter solution. It is shown that the designed converter has a higher efficiency than the commercial solution in the considered voltage range.

  14. A High Efficiency Boost Converter with MPPT Scheme for Low Voltage Thermoelectric Energy Harvesting

    NASA Astrophysics Data System (ADS)

    Guan, Mingjie; Wang, Kunpeng; Zhu, Qingyuan; Liao, Wei-Hsin

    2016-07-01

    Using thermoelectric elements to harvest energy from heat has been of great interest during the last decade. This paper presents a direct current-direct current (DC-DC) boost converter with a maximum power point tracking (MPPT) scheme for low input voltage thermoelectric energy harvesting applications. Zero current switch technique is applied in the proposed MPPT scheme. Theoretical analysis on the converter circuits is explored to derive the equations for parameters needed in the design of the boost converter. Simulations and experiments are carried out to verify the theoretical analysis and equations. A prototype of the designed converter is built using discrete components and a low-power microcontroller. The results show that the designed converter can achieve a high efficiency at low input voltage. The experimental efficiency of the designed converter is compared with a commercial converter solution. It is shown that the designed converter has a higher efficiency than the commercial solution in the considered voltage range.

  15. A secure and efficient password-based user authentication scheme using smart cards for the integrated EPR information system.

    PubMed

    Lee, Tian-Fu; Chang, I-Pin; Lin, Tsung-Hung; Wang, Ching-Cheng

    2013-06-01

    The integrated EPR information system supports convenient and rapid e-medicine services. A secure and efficient authentication scheme for the integrated EPR information system provides safeguarding patients' electronic patient records (EPRs) and helps health care workers and medical personnel to rapidly making correct clinical decisions. Recently, Wu et al. proposed an efficient password-based user authentication scheme using smart cards for the integrated EPR information system, and claimed that the proposed scheme could resist various malicious attacks. However, their scheme is still vulnerable to lost smart card and stolen verifier attacks. This investigation discusses these weaknesses and proposes a secure and efficient authentication scheme for the integrated EPR information system as alternative. Compared with related approaches, the proposed scheme not only retains a lower computational cost and does not require verifier tables for storing users' secrets, but also solves the security problems in previous schemes and withstands possible attacks.

  16. A secure and efficient password-based user authentication scheme using smart cards for the integrated EPR information system.

    PubMed

    Lee, Tian-Fu; Chang, I-Pin; Lin, Tsung-Hung; Wang, Ching-Cheng

    2013-06-01

    The integrated EPR information system supports convenient and rapid e-medicine services. A secure and efficient authentication scheme for the integrated EPR information system provides safeguarding patients' electronic patient records (EPRs) and helps health care workers and medical personnel to rapidly making correct clinical decisions. Recently, Wu et al. proposed an efficient password-based user authentication scheme using smart cards for the integrated EPR information system, and claimed that the proposed scheme could resist various malicious attacks. However, their scheme is still vulnerable to lost smart card and stolen verifier attacks. This investigation discusses these weaknesses and proposes a secure and efficient authentication scheme for the integrated EPR information system as alternative. Compared with related approaches, the proposed scheme not only retains a lower computational cost and does not require verifier tables for storing users' secrets, but also solves the security problems in previous schemes and withstands possible attacks. PMID:23553734

  17. Application of an efficient hybrid scheme for aeroelastic analysis of advanced propellers

    NASA Technical Reports Server (NTRS)

    Srivastava, R.; Sankar, N. L.; Reddy, T. S. R.; Huff, D. L.

    1989-01-01

    An efficient 3-D hybrid scheme is applied for solving Euler equations to analyze advanced propellers. The scheme treats the spanwise direction semi-explicitly and the other two directions implicitly, without affecting the accuracy, as compared to a fully implicit scheme. This leads to a reduction in computer time and memory requirement. The calculated power coefficients for two advanced propellers, SR3 and SR7L, and various advanced ratios showed good correlation with experiment. Spanwise distribution of elemental power coefficient and steady pressure coefficient differences also showed good agreement with experiment. A study of the effect of structural flexibility on the performance of the advanced propellers showed that structural deformation due to centrifugal and aero loading should be included for better correlation.

  18. An Automatic K-Point Grid Generation Scheme for Enhanced Efficiency and Accuracy in DFT Calculations

    NASA Astrophysics Data System (ADS)

    Mohr, Jennifer A.-F.; Shepherd, James J.; Alavi, Ali

    2013-03-01

    We seek to create an automatic k-point grid generation scheme for density functional theory (DFT) calculations that improves the efficiency and accuracy of the calculations and is suitable for use in high-throughput computations. Current automated k-point generation schemes often result in calculations with insufficient k-points, which reduces the reliability of the results, or too many k-points, which can significantly increase computational cost. By controlling a wider range of k-point grid densities for the Brillouin zone based upon factors of conductivity and symmetry, a scalable k-point grid generation scheme can lower calculation runtimes and improve the accuracy of energy convergence. Johns Hopkins University

  19. Cap and trade schemes on waste management: a case study of the landfill allowance trading scheme (LATS) in England.

    PubMed

    Calaf-Forn, Maria; Roca, Jordi; Puig-Ventosa, Ignasi

    2014-05-01

    The Landfill Allowance Trading Scheme (LATS) is one of the main instruments used in England to enforce the landfill diversion targets established in the Directive 1999/31/EC of the European Parliament and of the Council of 26 April 1999 on the landfill of waste (Landfill Directive). Through the LATS, biodegradable municipal waste (BMW) allowances for landfilling are allocated to each local authority, otherwise known as waste disposal authorities (WDAs). The quantity of landfill allowances received is expected to decrease continuously from 2005/06 to 2019/20 so as to meet the objectives of the Landfill Directive. To achieve their commitments, WDAs can exchange, buy, sell or transfer allowances among each other, or may re-profile their own allocation through banking and/or borrowing. Despite the goals for the first seven years - which included two target years (2005/06 and 2009/10) - being widely achieved (the average allocation of allowances per WDA was 22.9% higher than those finally used), market activity among WDAs was high and prices were not very stable. Results in terms of waste reduction and recycling levels have been satisfactory. The reduction of BMW landfilled (in percentage) was higher during the first seven years of the LATS period (2005/06-2011/12) (around 7% annually) than during the previous period (2001/02-2004/05) (4.2% annually). Since 2008, the significance of the LATS diminished because of an increase in the rate of the UK Landfill Tax. The LATS was suppressed after the 2012/13 target year, before what it was initially scheduled. The purpose of this paper is to describe the particularities of the LATS, analyse its performance as a waste management policy, make a comparison with the Landfill Tax, discuss its main features as regards efficiency, effectiveness and the application of the "polluter pays" principle and finally discuss if the effect of the increase in the Landfill Tax is what made the LATS ultimately unnecessary.

  20. High efficient key-insulated attribute based encryption scheme without bilinear pairing operations.

    PubMed

    Hong, Hanshu; Sun, Zhixin

    2016-01-01

    Attribute based encryption (ABE) has been widely applied for secure data protection in various data sharing systems. However, the efficiency of existing ABE schemes is not high enough since running encrypt and decrypt algorithms need frequent bilinear pairing operations, which may occupy too much computing resources on terminal devices. What's more, since different users may share the same attributes in the system, a single user's private key exposure will threaten the security and confidentiality of the whole system. Therefore, to further decrease the computation cost in attribute based cryptosystem as well as provide secure protection when key exposure happens, in this paper, we firstly propose a high efficient key-insulated ABE algorithm without pairings. The key-insulated mechanism guarantees both forward security and backward security when key exposure or user revocation happens. Besides, during the running of algorithms in our scheme, users and attribute authority needn't run any bilinear pairing operations, which will increase the efficiency to a large extent. The high efficiency and security analysis indicate that our scheme is more appropriate for secure protection in data sharing systems.

  1. Efficient and provable secure pairing-free security-mediated identity-based identification schemes.

    PubMed

    Chin, Ji-Jian; Tan, Syh-Yuan; Heng, Swee-Huay; Phan, Raphael C-W

    2014-01-01

    Security-mediated cryptography was first introduced by Boneh et al. in 2001. The main motivation behind security-mediated cryptography was the capability to allow instant revocation of a user's secret key by necessitating the cooperation of a security mediator in any given transaction. Subsequently in 2003, Boneh et al. showed how to convert a RSA-based security-mediated encryption scheme from a traditional public key setting to an identity-based one, where certificates would no longer be required. Following these two pioneering papers, other cryptographic primitives that utilize a security-mediated approach began to surface. However, the security-mediated identity-based identification scheme (SM-IBI) was not introduced until Chin et al. in 2013 with a scheme built on bilinear pairings. In this paper, we improve on the efficiency results for SM-IBI schemes by proposing two schemes that are pairing-free and are based on well-studied complexity assumptions: the RSA and discrete logarithm assumptions.

  2. Efficient and Provable Secure Pairing-Free Security-Mediated Identity-Based Identification Schemes

    PubMed Central

    Chin, Ji-Jian; Tan, Syh-Yuan; Heng, Swee-Huay; Phan, Raphael C.-W.

    2014-01-01

    Security-mediated cryptography was first introduced by Boneh et al. in 2001. The main motivation behind security-mediated cryptography was the capability to allow instant revocation of a user's secret key by necessitating the cooperation of a security mediator in any given transaction. Subsequently in 2003, Boneh et al. showed how to convert a RSA-based security-mediated encryption scheme from a traditional public key setting to an identity-based one, where certificates would no longer be required. Following these two pioneering papers, other cryptographic primitives that utilize a security-mediated approach began to surface. However, the security-mediated identity-based identification scheme (SM-IBI) was not introduced until Chin et al. in 2013 with a scheme built on bilinear pairings. In this paper, we improve on the efficiency results for SM-IBI schemes by proposing two schemes that are pairing-free and are based on well-studied complexity assumptions: the RSA and discrete logarithm assumptions. PMID:25207333

  3. Efficient and provable secure pairing-free security-mediated identity-based identification schemes.

    PubMed

    Chin, Ji-Jian; Tan, Syh-Yuan; Heng, Swee-Huay; Phan, Raphael C-W

    2014-01-01

    Security-mediated cryptography was first introduced by Boneh et al. in 2001. The main motivation behind security-mediated cryptography was the capability to allow instant revocation of a user's secret key by necessitating the cooperation of a security mediator in any given transaction. Subsequently in 2003, Boneh et al. showed how to convert a RSA-based security-mediated encryption scheme from a traditional public key setting to an identity-based one, where certificates would no longer be required. Following these two pioneering papers, other cryptographic primitives that utilize a security-mediated approach began to surface. However, the security-mediated identity-based identification scheme (SM-IBI) was not introduced until Chin et al. in 2013 with a scheme built on bilinear pairings. In this paper, we improve on the efficiency results for SM-IBI schemes by proposing two schemes that are pairing-free and are based on well-studied complexity assumptions: the RSA and discrete logarithm assumptions. PMID:25207333

  4. An efficient, unconditionally energy stable local discontinuous Galerkin scheme for the Cahn-Hilliard-Brinkman system

    NASA Astrophysics Data System (ADS)

    Guo, Ruihan; Xu, Yan

    2015-10-01

    In this paper, we present an efficient and unconditionally energy stable fully-discrete local discontinuous Galerkin (LDG) method for approximating the Cahn-Hilliard-Brinkman (CHB) system, which is comprised of a Cahn-Hilliard type equation and a generalized Brinkman equation modeling fluid flow. The semi-discrete energy stability of the LDG method is proved firstly. Due to the strict time step restriction (Δt = O (Δx4)) of explicit time discretization methods for stability, we introduce a semi-implicit scheme which consists of the implicit Euler method combined with a convex splitting of the discrete Cahn-Hilliard energy strategy for the temporal discretization. The unconditional energy stability of this fully-discrete convex splitting scheme is also proved. Obviously, the fully-discrete equations at the implicit time level are nonlinear, and to enhance the efficiency of the proposed approach, the nonlinear Full Approximation Scheme (FAS) multigrid method has been employed to solve this system of algebraic equations. We also show the nearly optimal complexity numerically. Numerical experiments based on the overall solution method of combining the proposed LDG method, convex splitting scheme and the nonlinear multigrid solver are given to validate the theoretical results and to show the effectiveness of the proposed approach for the CHB system.

  5. A Study on Efficient Mobile IPv6 Fast Handover Scheme Using Reverse Binding Mechanism

    NASA Astrophysics Data System (ADS)

    Tolentino, Randy S.; Lee, Kijeong; Kim, Sung-Gyu; Kim, Miso; Park, Byungjoo

    This paper proposes a solution for solving the packet handover issues of MIPv6. We propose an efficient scheme that can support fast handover effectively in standard Mobile IPv6 (MIPv6) by optimizing the associated data and the flow of signal during handover. A new signaling message Reverse Packet Binding Mechanism is defined and utilized to hasten the handover procedure by adding a buffer in access point (AP) and home agent (HA).

  6. Development of an adaptive tsetse population management scheme for the Luke community, Ethiopia.

    PubMed

    Sciarretta, Andrea; Girma, Melaku; Tikubet, Getachew; Belayehun, Lulseged; Ballo, Shifa; Baumgärtner, Johann

    2005-11-01

    Since 1996, tsetse (Glossina spp.) control operations, using odor-baited traps, have been carried out in the Luke area of Gurage zone, southwestern Ethiopia. Glossina morsitans submorsitans Newstead was identified as the dominant species in the area, but the presence of Glossina fuscipes Newstead and Glossina pallidipes Austen also was recorded. Here, we refer to the combined number of these three species and report the work undertaken from October 2002 to October 2004 to render the control system more efficient by reducing the number of traps used and maintaining the previously reached levels of tsetse occurrence and trypanosomiasis prevalence. This was done by the design and implementation of an adaptive tsetse population management system. It consists first of an efficient community-participatory monitoring scheme that allowed us to reduce the number of traps used from 216 to 127 (107 monitoring traps and 20 control traps). Geostatistical methods, including kriging and mapping, furthermore allowed identification and monitoring of the spatiotemporal dynamics of patches with increased fly densities, referred to as hot spots. To respond to hot spots, the Luke community was advised and assisted in control trap deployment. Adaptive management was shown to be more efficient than the previously used mass trapping system. In that context, trap numbers could be reduced substantially, at the same time maintaining previously achieved levels of tsetse occurrences and disease prevalence.

  7. Cap and trade schemes on waste management: A case study of the Landfill Allowance Trading Scheme (LATS) in England

    SciTech Connect

    Calaf-Forn, Maria; Roca, Jordi; Puig-Ventosa, Ignasi

    2014-05-01

    Highlights: • LATS has been effective to achieve a reduction of the amount of landfilled waste. • LATS has been one of the few environmental instruments for waste management with a cap and trade methodology. • LATS has achieved to increase recycling of the biodegradable and other waste fractions. - Abstract: The Landfill Allowance Trading Scheme (LATS) is one of the main instruments used in England to enforce the landfill diversion targets established in the Directive 1999/31/EC of the European Parliament and of the Council of 26 April 1999 on the landfill of waste (Landfill Directive). Through the LATS, biodegradable municipal waste (BMW) allowances for landfilling are allocated to each local authority, otherwise known as waste disposal authorities (WDAs). The quantity of landfill allowances received is expected to decrease continuously from 2005/06 to 2019/20 so as to meet the objectives of the Landfill Directive. To achieve their commitments, WDAs can exchange, buy, sell or transfer allowances among each other, or may re-profile their own allocation through banking and/or borrowing. Despite the goals for the first seven years – which included two target years (2005/06 and 2009/10) – being widely achieved (the average allocation of allowances per WDA was 22.9% higher than those finally used), market activity among WDAs was high and prices were not very stable. Results in terms of waste reduction and recycling levels have been satisfactory. The reduction of BMW landfilled (in percentage) was higher during the first seven years of the LATS period (2005/06–2011/12) (around 7% annually) than during the previous period (2001/02–2004/05) (4.2% annually). Since 2008, the significance of the LATS diminished because of an increase in the rate of the UK Landfill Tax. The LATS was suppressed after the 2012/13 target year, before what it was initially scheduled. The purpose of this paper is to describe the particularities of the LATS, analyse its performance as

  8. An Efficient and Practical Smart Card Based Anonymity Preserving User Authentication Scheme for TMIS using Elliptic Curve Cryptography.

    PubMed

    Amin, Ruhul; Islam, S K Hafizul; Biswas, G P; Khan, Muhammad Khurram; Kumar, Neeraj

    2015-11-01

    In the last few years, numerous remote user authentication and session key agreement schemes have been put forwarded for Telecare Medical Information System, where the patient and medical server exchange medical information using Internet. We have found that most of the schemes are not usable for practical applications due to known security weaknesses. It is also worth to note that unrestricted number of patients login to the single medical server across the globe. Therefore, the computation and maintenance overhead would be high and the server may fail to provide services. In this article, we have designed a medical system architecture and a standard mutual authentication scheme for single medical server, where the patient can securely exchange medical data with the doctor(s) via trusted central medical server over any insecure network. We then explored the security of the scheme with its resilience to attacks. Moreover, we formally validated the proposed scheme through the simulation using Automated Validation of Internet Security Schemes and Applications software whose outcomes confirm that the scheme is protected against active and passive attacks. The performance comparison demonstrated that the proposed scheme has lower communication cost than the existing schemes in literature. In addition, the computation cost of the proposed scheme is nearly equal to the exiting schemes. The proposed scheme not only efficient in terms of different security attacks, but it also provides an efficient login, mutual authentication, session key agreement and verification and password update phases along with password recovery.

  9. An Efficient and Practical Smart Card Based Anonymity Preserving User Authentication Scheme for TMIS using Elliptic Curve Cryptography.

    PubMed

    Amin, Ruhul; Islam, S K Hafizul; Biswas, G P; Khan, Muhammad Khurram; Kumar, Neeraj

    2015-11-01

    In the last few years, numerous remote user authentication and session key agreement schemes have been put forwarded for Telecare Medical Information System, where the patient and medical server exchange medical information using Internet. We have found that most of the schemes are not usable for practical applications due to known security weaknesses. It is also worth to note that unrestricted number of patients login to the single medical server across the globe. Therefore, the computation and maintenance overhead would be high and the server may fail to provide services. In this article, we have designed a medical system architecture and a standard mutual authentication scheme for single medical server, where the patient can securely exchange medical data with the doctor(s) via trusted central medical server over any insecure network. We then explored the security of the scheme with its resilience to attacks. Moreover, we formally validated the proposed scheme through the simulation using Automated Validation of Internet Security Schemes and Applications software whose outcomes confirm that the scheme is protected against active and passive attacks. The performance comparison demonstrated that the proposed scheme has lower communication cost than the existing schemes in literature. In addition, the computation cost of the proposed scheme is nearly equal to the exiting schemes. The proposed scheme not only efficient in terms of different security attacks, but it also provides an efficient login, mutual authentication, session key agreement and verification and password update phases along with password recovery. PMID:26433889

  10. Efficient high-order discontinuous Galerkin schemes with first-order hyperbolic advection-diffusion system approach

    NASA Astrophysics Data System (ADS)

    Mazaheri, Alireza; Nishikawa, Hiroaki

    2016-09-01

    We propose arbitrary high-order discontinuous Galerkin (DG) schemes that are designed based on a first-order hyperbolic advection-diffusion formulation of the target governing equations. We present, in details, the efficient construction of the proposed high-order schemes (called DG-H), and show that these schemes have the same number of global degrees-of-freedom as comparable conventional high-order DG schemes, produce the same or higher order of accuracy solutions and solution gradients, are exact for exact polynomial functions, and do not need a second-derivative diffusion operator. We demonstrate that the constructed high-order schemes give excellent quality solution and solution gradients on irregular triangular elements. We also construct a Weighted Essentially Non-Oscillatory (WENO) limiter for the proposed DG-H schemes and apply it to discontinuous problems. We also make some accuracy comparisons with conventional DG and interior penalty schemes. A relative qualitative cost analysis is also reported, which indicates that the high-order schemes produce orders of magnitude more accurate results than the low-order schemes for a given CPU time. Furthermore, we show that the proposed DG-H schemes are nearly as efficient as the DG and Interior-Penalty (IP) schemes as these schemes produce results that are relatively at the same error level for approximately a similar CPU time.

  11. Developing Efficient Coordination Schemes to Control Over-Pumping in the Heihe River Basin, China

    NASA Astrophysics Data System (ADS)

    Pedrazzini, G.

    2015-12-01

    Many wicked water resources problems are approached in a social planner perspective. This not always matches the real institutional and policy-making context, where, rather, multiple decision-makers (DMs) can act independently, or weakly cooperate, ultimately producing system-wide inefficient trade-offs. The idea in this work is to adopt a more realistic approach, where the multi-DMs nature of the problem is preserved and the uncoordinated DMs are driven, thorough coordination mechanisms, towards a more system-wide efficient solution. An agent-based modelling framework linked to a surface and groundwater model is used to design these coordination mechanisms as constraints to the independent agents (i.e., DMs) behaviour. In the Heihe Basin the ongoing introduction of smart meter IC-card systems on farmers' pumping wells will soon allow monitoring and control of abstractions with the goal of preventing further depletion of the resource. The major interest of policy makers in the region concerns the development of new and the improvement of existing legislation on pricing schemes and/or groundwater quotas. The model outcome where agents act rationally but selfishly is compared to the optimal solution at system-level assuming perfect coordination and cooperation. The optimal solutions with respect to the given utility functions are computed using nonlinear optimization with a rolling out time horizon. The Pareto-Frontier is synthesized through an exhaustive sampling of the weight coefficient space and related to the current and to the historical management of the last 4 decades. The best parameter values for the proposed coordination mechanisms are determined and the alternatives are compared with respect to their efficiency and acceptability. Preliminary results suggest that a regulatory tax on groundwater of about a factor 10 of the current resource fee is required to increase the elasticity of the groundwater demand curve such that reducing consumption becomes

  12. The performance evaluation of a new neural network based traffic management scheme for a satellite communication network

    NASA Technical Reports Server (NTRS)

    Ansari, Nirwan; Liu, Dequan

    1991-01-01

    A neural-network-based traffic management scheme for a satellite communication network is described. The scheme consists of two levels of management. The front end of the scheme is a derivation of Kohonen's self-organization model to configure maps for the satellite communication network dynamically. The model consists of three stages. The first stage is the pattern recognition task, in which an exemplar map that best meets the current network requirements is selected. The second stage is the analysis of the discrepancy between the chosen exemplar map and the state of the network, and the adaptive modification of the chosen exemplar map to conform closely to the network requirement (input data pattern) by means of Kohonen's self-organization. On the basis of certain performance criteria, whether a new map is generated to replace the original chosen map is decided in the third stage. A state-dependent routing algorithm, which arranges the incoming call to some proper path, is used to make the network more efficient and to lower the call block rate. Simulation results demonstrate that the scheme, which combines self-organization and the state-dependent routing mechanism, provides better performance in terms of call block rate than schemes that only have either the self-organization mechanism or the routing mechanism.

  13. Decentralising Zimbabwe’s water management: The case of Guyu-Chelesa irrigation scheme

    NASA Astrophysics Data System (ADS)

    Tambudzai, Rashirayi; Everisto, Mapedza; Gideon, Zhou

    Smallholder irrigation schemes are largely supply driven such that they exclude the beneficiaries on the management decisions and the choice of the irrigation schemes that would best suit their local needs. It is against this background that the decentralisation framework and the Dublin Principles on Integrated Water Resource Management (IWRM) emphasise the need for a participatory approach to water management. The Zimbabwean government has gone a step further in decentralising the management of irrigation schemes, that is promoting farmer managed irrigation schemes so as to ensure effective management of scarce community based land and water resources. The study set to investigate the way in which the Guyu-Chelesa irrigation scheme is managed with specific emphasis on the role of the Irrigation Management Committee (IMC), the level of accountability and the powers devolved to the IMC. Merrey’s 2008 critique of IWRM also informs this study which views irrigation as going beyond infrastructure by looking at how institutions and decision making processes play out at various levels including at the irrigation scheme level. The study was positioned on the hypothesis that ‘decentralised or autonomous irrigation management enhances the sustainability and effectiveness of irrigation schemes’. To validate or falsify the stated hypothesis, data was gathered using desk research in the form of reviewing articles, documents from within the scheme and field research in the form of questionnaire surveys, key informant interviews and field observation. The Statistical Package for Social Sciences was used to analyse data quantitatively, whilst content analysis was utilised to analyse qualitative data whereby data was analysed thematically. Comparative analysis was carried out as Guyu-Chelesa irrigation scheme was compared with other smallholder irrigation scheme’s experiences within Zimbabwe and the Sub Saharan African region at large. The findings were that whilst the

  14. Toxicological mass disaster management - a hospital deployment scheme.

    PubMed

    Baniel, J; Ram, Z; Kami, A; Schindel, D

    1986-09-01

    Toxicological mass disasters have occurred frequently in past years and constitute a permanent threat in urban areas. From the standpoint of hospital planning, special consideration is required to treat a large number of poisoned casualties in a relatively short period. Several unique medical aspects characterize toxicological mass disasters: casualties present a single disease entity with many "borderline" cases, most medical personnel are unfamiliar with the problem and casualties present a potential contamination hazard to the hospital. A hospital deployment scheme is presented recommending Decontamination, Triage and simple Treatment Algorithms to meet the medical and organizational challenge of such a mass casualty situation. A further specific deployment scheme for treatment of organophosphorus agents poisoning is described to illustrate the principles presented.

  15. Towards an Efficient Flooding Scheme Exploiting 2-Hop Backward Information in MANETs

    NASA Astrophysics Data System (ADS)

    Le, Trong Duc; Choo, Hyunseung

    Flooding is an indispensable operation for providing control or routing functionalities to mobile ad hoc networks (MANETs). Previously, many flooding schemes have been studied with the intention of curtailing the problems of severe redundancies, contention, and collisions in traditional implementations. A recent approach with relatively high efficiency is 1HI by Liu et al., which uses only 1-hop neighbor information. The scheme achieves local optimality in terms of the number of retransmission nodes with time complexity &Theta(n log n), where n is the number of neighbors of a node; however, this method tends to make many redundant transmissions. In this paper, we present a novel flooding algorithm, 2HBI (2-hop backward information), that efficiently reduces the number of retransmission nodes and solves the broadcast storm problem in ad hoc networks using our proposed concept, “2-hop backward information.” The most significant feature of the proposed algorithm is that it does not require any extra communication overhead other than the exchange of 1-hop HELLO messages but maintains high deliverability. Comprehensive computer simulations show that the proposed scheme significantly reduces redundant transmissions in 1HI and in pure flooding, up to 38% and 91%, respectively; accordingly it alleviates contention and collisions in networks.

  16. Efficient alignment scheme for zone-plates-based transmission soft X-ray microscope

    NASA Astrophysics Data System (ADS)

    Lim, Jun; Shin, Hyun-Joon; Hong, Chung Ki

    2010-12-01

    Alignment and operation of a zone-plate (ZP)-based transmission soft X-ray microscope (TXM) is difficult and time consuming, especially when the TXM has no dedicated X-ray source. We introduce here an efficient TXM alignment scheme. The TXM employed is a simple in-situ-experiment-capable setup. It includes ultrahigh-vacuum (UHV)-compatible conflat flanges and is mountable in tandem with any soft X-ray synchrotron radiation beamlines. Obtaining zeroth- and first-order diffracted (condenser-zone-plate [CZP]-focused) beams simultaneously by means of the objective zone plate (OZP) is the most essential step in the alignment scheme. We were able to acquire, in one hour at a radiation wavelength of 2.49 nm, an image of 50 nm spatial resolution.

  17. Energy Efficient In-network RFID Data Filtering Scheme in Wireless Sensor Networks

    PubMed Central

    Bashir, Ali Kashif; Lim, Se-Jung; Hussain, Chauhdary Sajjad; Park, Myong-Soon

    2011-01-01

    RFID (Radio frequency identification) and wireless sensor networks are backbone technologies for pervasive environments. In integration of RFID and WSN, RFID data uses WSN protocols for multi-hop communications. Energy is a critical issue in WSNs; however, RFID data contains a lot of duplication. These duplications can be eliminated at the base station, but unnecessary transmissions of duplicate data within the network still occurs, which consumes nodes’ energy and affects network lifetime. In this paper, we propose an in-network RFID data filtering scheme that efficiently eliminates the duplicate data. For this we use a clustering mechanism where cluster heads eliminate duplicate data and forward filtered data towards the base station. Simulation results prove that our approach saves considerable amounts of energy in terms of communication and computational cost, compared to existing filtering schemes. PMID:22163999

  18. An efficient scheme for automatic web pages categorization using the support vector machine

    NASA Astrophysics Data System (ADS)

    Bhalla, Vinod Kumar; Kumar, Neeraj

    2016-07-01

    In the past few years, with an evolution of the Internet and related technologies, the number of the Internet users grows exponentially. These users demand access to relevant web pages from the Internet within fraction of seconds. To achieve this goal, there is a requirement of an efficient categorization of web page contents. Manual categorization of these billions of web pages to achieve high accuracy is a challenging task. Most of the existing techniques reported in the literature are semi-automatic. Using these techniques, higher level of accuracy cannot be achieved. To achieve these goals, this paper proposes an automatic web pages categorization into the domain category. The proposed scheme is based on the identification of specific and relevant features of the web pages. In the proposed scheme, first extraction and evaluation of features are done followed by filtering the feature set for categorization of domain web pages. A feature extraction tool based on the HTML document object model of the web page is developed in the proposed scheme. Feature extraction and weight assignment are based on the collection of domain-specific keyword list developed by considering various domain pages. Moreover, the keyword list is reduced on the basis of ids of keywords in keyword list. Also, stemming of keywords and tag text is done to achieve a higher accuracy. An extensive feature set is generated to develop a robust classification technique. The proposed scheme was evaluated using a machine learning method in combination with feature extraction and statistical analysis using support vector machine kernel as the classification tool. The results obtained confirm the effectiveness of the proposed scheme in terms of its accuracy in different categories of web pages.

  19. Cap and trade schemes on waste management: a case study of the landfill allowance trading scheme (LATS) in England.

    PubMed

    Calaf-Forn, Maria; Roca, Jordi; Puig-Ventosa, Ignasi

    2014-05-01

    The Landfill Allowance Trading Scheme (LATS) is one of the main instruments used in England to enforce the landfill diversion targets established in the Directive 1999/31/EC of the European Parliament and of the Council of 26 April 1999 on the landfill of waste (Landfill Directive). Through the LATS, biodegradable municipal waste (BMW) allowances for landfilling are allocated to each local authority, otherwise known as waste disposal authorities (WDAs). The quantity of landfill allowances received is expected to decrease continuously from 2005/06 to 2019/20 so as to meet the objectives of the Landfill Directive. To achieve their commitments, WDAs can exchange, buy, sell or transfer allowances among each other, or may re-profile their own allocation through banking and/or borrowing. Despite the goals for the first seven years - which included two target years (2005/06 and 2009/10) - being widely achieved (the average allocation of allowances per WDA was 22.9% higher than those finally used), market activity among WDAs was high and prices were not very stable. Results in terms of waste reduction and recycling levels have been satisfactory. The reduction of BMW landfilled (in percentage) was higher during the first seven years of the LATS period (2005/06-2011/12) (around 7% annually) than during the previous period (2001/02-2004/05) (4.2% annually). Since 2008, the significance of the LATS diminished because of an increase in the rate of the UK Landfill Tax. The LATS was suppressed after the 2012/13 target year, before what it was initially scheduled. The purpose of this paper is to describe the particularities of the LATS, analyse its performance as a waste management policy, make a comparison with the Landfill Tax, discuss its main features as regards efficiency, effectiveness and the application of the "polluter pays" principle and finally discuss if the effect of the increase in the Landfill Tax is what made the LATS ultimately unnecessary. PMID:24661742

  20. A secure and efficient uniqueness-and-anonymity-preserving remote user authentication scheme for connected health care.

    PubMed

    Das, Ashok Kumar; Goswami, Adrijit

    2013-06-01

    Connected health care has several applications including telecare medicine information system, personally controlled health records system, and patient monitoring. In such applications, user authentication can ensure the legality of patients. In user authentication for such applications, only the legal user/patient himself/herself is allowed to access the remote server, and no one can trace him/her according to transmitted data. Chang et al. proposed a uniqueness-and-anonymity-preserving remote user authentication scheme for connected health care (Chang et al., J Med Syst 37:9902, 2013). Their scheme uses the user's personal biometrics along with his/her password with the help of the smart card. The user's biometrics is verified using BioHashing. Their scheme is efficient due to usage of one-way hash function and exclusive-or (XOR) operations. In this paper, we show that though their scheme is very efficient, their scheme has several security weaknesses such as (1) it has design flaws in login and authentication phases, (2) it has design flaws in password change phase, (3) it fails to protect privileged insider attack, (4) it fails to protect the man-in-the middle attack, and (5) it fails to provide proper authentication. In order to remedy these security weaknesses in Chang et al.'s scheme, we propose an improvement of their scheme while retaining the original merit of their scheme. We show that our scheme is efficient as compared to Chang et al.'s scheme. Through the security analysis, we show that our scheme is secure against possible attacks. Further, we simulate our scheme for the formal security verification using the widely-accepted AVISPA (Automated Validation of Internet Security Protocols and Applications) tool to ensure that our scheme is secure against passive and active attacks. In addition, after successful authentication between the user and the server, they establish a secret session key shared between them for future secure communication. PMID

  1. Efficient quantum secret sharing scheme with two-particle entangled states

    NASA Astrophysics Data System (ADS)

    Zhu, Zhen-Chao; Zhang, Yu-Qing; Fu, An-Min

    2011-04-01

    This paper proposes a protocol for multi-party quantum secret sharing utilizing four non-orthogonal two-particle entangled states following some ideas in the schemes proposed by Liu et al. (2006 Chin. Phys. Lett. 23 3148) and Zhang et al. (2009 Chin. Phys. B 18 2149) respectively. The theoretical efficiency for qubits of the new protocol is improved from 50% to approaching 100%. All the entangled states can be used for generating the private key except those used for the eavesdropping check. The validity of a probable attack called opaque cheat attack to this kind of protocols is considered in the paper for the first time.

  2. An Efficient Molecular Dynamics Scheme for Predicting Dopant Implant Profiles in Semiconductors

    SciTech Connect

    Beardmore, K.M.; Gronbech-Jensen, N.

    1998-09-15

    The authors present a highly efficient molecular dynamics scheme for calculating the concentration profile of dopants implanted in group-IV alloy, and III-V zinc blende structure materials. The program incorporates methods for reducing computational overhead, plus a rare event algorithm to give statistical accuracy over several orders of magnitude change in the dopant concentration. The code uses a molecular dynamics (MD) model, instead of the binary collision approximation (BCA) used in implant simulators such as TRIM and Marlowe, to describe ion-target interactions. Atomic interactions are described by a combination of 'many-body' and screened Coulomb potentials. Inelastic energy loss is accounted for using a Firsov model, and electronic stopping is described by a Brandt-Kitagawa model which contains the single adjustable parameter for the entire scheme. Thus, the program is easily extensible to new ion-target combinations with the minimum of tuning, and is predictive over a wide range of implant energies and angles. The scheme is especially suited for calculating profiles due to low energy, large angle implants, and for situations where a predictive capability is required with the minimum of experimental validation. They give examples of using their code to calculate concentration profiles and 2D 'point response' profiles of dopants in crystalline silicon, silicon-germanium blends, and gallium-arsenide. They can predict the experimental profiles over five orders of magnitude for <100> and <110> channeling and for non-channeling implants at energies up to hundreds of keV.

  3. Efficient massively parallel simulation of dynamic channel assignment schemes for wireless cellular communications

    NASA Technical Reports Server (NTRS)

    Greenberg, Albert G.; Lubachevsky, Boris D.; Nicol, David M.; Wright, Paul E.

    1994-01-01

    Fast, efficient parallel algorithms are presented for discrete event simulations of dynamic channel assignment schemes for wireless cellular communication networks. The driving events are call arrivals and departures, in continuous time, to cells geographically distributed across the service area. A dynamic channel assignment scheme decides which call arrivals to accept, and which channels to allocate to the accepted calls, attempting to minimize call blocking while ensuring co-channel interference is tolerably low. Specifically, the scheme ensures that the same channel is used concurrently at different cells only if the pairwise distances between those cells are sufficiently large. Much of the complexity of the system comes from ensuring this separation. The network is modeled as a system of interacting continuous time automata, each corresponding to a cell. To simulate the model, conservative methods are used; i.e., methods in which no errors occur in the course of the simulation and so no rollback or relaxation is needed. Implemented on a 16K processor MasPar MP-1, an elegant and simple technique provides speedups of about 15 times over an optimized serial simulation running on a high speed workstation. A drawback of this technique, typical of conservative methods, is that processor utilization is rather low. To overcome this, new methods were developed that exploit slackness in event dependencies over short intervals of time, thereby raising the utilization to above 50 percent and the speedup over the optimized serial code to about 120 times.

  4. Damping efficiency of the Tchamwa-Wielgosz explicit dissipative scheme under instantaneous loading conditions

    NASA Astrophysics Data System (ADS)

    Mahéo, Laurent; Grolleau, Vincent; Rio, Gérard

    2009-11-01

    To deal with dynamic and wave propagation problems, dissipative methods are often used to reduce the effects of the spurious oscillations induced by the spatial and time discretization procedures. Among the many dissipative methods available, the Tchamwa-Wielgosz (TW) explicit scheme is particularly useful because it damps out the spurious oscillations occurring in the highest frequency domain. The theoretical study performed here shows that the TW scheme is decentered to the right, and that the damping can be attributed to a nodal displacement perturbation. The FEM study carried out using instantaneous 1-D and 3-D compression loads shows that it is useful to display the damping versus the number of time steps in order to obtain a constant damping efficiency whatever the size of element used for the regular meshing. A study on the responses obtained with irregular meshes shows that the TW scheme is only slightly sensitive to the spatial discretization procedure used. To cite this article: L. Mahéo et al., C. R. Mecanique 337 (2009).

  5. Topological invariants for interacting topological insulators. I. Efficient numerical evaluation scheme and implementations

    NASA Astrophysics Data System (ADS)

    He, Yuan-Yao; Wu, Han-Qing; Meng, Zi Yang; Lu, Zhong-Yi

    2016-05-01

    The aim of this series of two papers is to discuss topological invariants for interacting topological insulators (TIs). In the first paper (I), we provide a paradigm of efficient numerical evaluation scheme for topological invariants, in which we demystify the procedures and techniques employed in calculating Z2 invariant and spin Chern number via zero-frequency single-particle Green's function in quantum Monte Carlo (QMC) simulations. Here we introduce an interpolation process to overcome the ubiquitous finite-size effect, so that the calculated spin Chern number shows ideally quantized values. We also show that making use of symmetry properties of the underlying systems can greatly reduce the computational effort. To demonstrate the effectiveness of our numerical evaluation scheme, especially the interpolation process, for calculating topological invariants, we apply it on two independent two-dimensional models of interacting topological insulators. In the subsequent paper (II), we apply the scheme developed here to wider classes of models of interacting topological insulators, for which certain limitation of constructing topological invariant via single-particle Green's functions will be presented.

  6. Simulation study on the efficiencies of MOET nucleus breeding schemes applying marker assisted selection in dairy cattle.

    PubMed

    Luo, WeiZhen; Wang, YaChun; Zhang, Yuan

    2009-03-01

    Advantages of breeding schemes using genetic marker information and/or multiple ovulation and embryo transfer (MOET) technology over the traditional approach were extensively evaluated through simulation. Milk yield was the trait of interest and QTL was the genetic marker utilized. Eight dairy cattle breeding scenarios were considered, i.e., traditional progeny testing breeding scheme (denoted as STANPT), GASPT scheme including a pre-selection of young bulls entering progeny testing based on their own QTL information, MOETPT scheme using MOET technology to generate young bulls and a selection of young bulls limited within the full-sib family, GAMOPT scheme adopting both QTL pre-selection and MOET technology, COMBPT scheme using a mixed linear model which considered QTL genotype instead of the BLUP model in GAMOPT, and three non-progeny testing schemes, i.e. the MOET, GAMO and COMB schemes, corresponding to MOETPT, GAMOPT and COMBPT with progeny testing being part of the system. Animals were selected based on their breeding value which was estimated under an animal model framework. Sequential selection over 17 years was performed in the simulations and 30 replicates were designed for each scenario. The influences of using QTL information and MOET technology on favorable QTL allele frequency, true breeding values, polygenetic breeding values and the accumulated genetic superiority were extensively evaluated, for five different populations including active sires, lactating cows, bull dams, bull sires, and young bulls. The results showed that the combined schemes significantly outperformed other approaches wherein accumulated true breeding value progressed. The difference between schemes exclusively using QTL information or MOET technology was not significant. The STANPT scheme was the least efficient among the 8 schemes. The schemes using MOET technology had a higher polygenetic response than others in the 17th year. The increases of frequency of the favorable QTL

  7. [CESAMES, French-speaking international scheme for health managers].

    PubMed

    Montserrat, X

    2001-01-01

    A "Programme de création du Cycle d'Etudes Supérieures Africain en Management des Etablissements Sanitaires" (CESAMES, Plan for African hospital management senior course) was officially launched during the VIth International Hospital Events, organised in Libreville (Gabon) from November 21-23rd 2000. In the context of health systems reforms in African countries, priority is given to adapting and upgrading the qualifications of health care managers. Creating CESAMES is a major element within a general strategy aiming at supporting health systems and present reforms. The aim is to develop, from an African teaching body, a French-speaking pool of skills in order to increase the managers' expertise and to address the problem of critical mass of professionals for training within each country. Creating an international training pool will produce a human resources development and expansion tool in the area of health institutions management. This programme should ensure the transfer of know-how and capitalization between training centres. Beyond the training system, creating CESAMES should expand the documentation resources and ensure the creation of a French-speaking professional network of health institution managers.

  8. Improving resource efficiency through management science.

    PubMed

    Revere, Lee; Roberts, Ralph

    2004-01-01

    Optimal management of resources is a very complex and difficult task for healthcare systems. Nevertheless, healthcare providers can employ data-driven methodologies and management science tools, coupled with managerial insights, to significantly improve both their resource effectiveness and efficiency. Understanding the full technical complexities of management science models is a daunting task for healthcare managers, but they can be aided by the increased availability of management science software. Readily available software does not require extensive technical competencies and is easily adaptable to resource changes. This article reports how a large healthcare system improved the cost effectiveness and service efficiency of its laboratory courier service through the use of management science techniques and readily available software. The laboratory courier system existed to serve a large multihospital healthcare system located in a major Texas metropolis. The routing and scheduling solution reported in this article yielded a very substantial 16.4 percent reduction in annual laboratory courier costs and a significant improvement in service levels. This study indicates that management science techniques and software are readily adaptable to the healthcare environment and are amenable to use by healthcare administrators. PMID:15499806

  9. Efficient Z-scheme charge separation in novel vertically aligned ZnO/CdSSe nanotrees

    NASA Astrophysics Data System (ADS)

    Li, Zhengxin; Nieto-Pescador, Jesus; Carson, Alexander J.; Blake, Jolie C.; Gundlach, Lars

    2016-04-01

    A new tree-like ZnO/CdSSe nanocomposite with CdSSe branches grown on ZnO nanowires prepared via a two-step chemical vapor deposition is presented. The nanotrees (NTs) are vertically aligned on a substrate. The CdSSe branches result in strong visible light absorption and form a type-II heterojunction with the ZnO stem that facilitates efficient electron transfer. A combination of photoluminescence spectroscopy and lifetime measurements indicates that the NTs are promising materials for applications that benefit from a Z-scheme charge transfer mechanism. Vertically aligned branched ZnO nanowires can provide direct electron transport pathways to substrates and allow for efficient charge separation. These advantages of nanoscale hierarchical heterostructures make ZnO/CdSSe NTs a promising semiconductor material for solar cells, and other opto-electronic devices.

  10. Managing air to improve combustion efficiency

    SciTech Connect

    Storm, R.F.; Storm, S.K.; Hall, S.G.

    2007-10-15

    Managing the air flow first and then the fuel flow can obtain the best combustion results possible given the constraints of the boiler design. A case study for a typical 500 MW pulverised coal boiler is given where a set of best practices to measure, balance and control furnace inputs to achieve higher combustion efficiencies and lower NOx emissions is applied. 10 figs.

  11. An Efficient Dual Charge Pump Circuit Using Charge Sharing Clock Scheme

    NASA Astrophysics Data System (ADS)

    Huang, Mengshu; Zhang, Yimeng; Yoshihara, Tsutomu

    In this paper, the charge pump efficiency is discussed, and a dual charge pump circuit with complementary architecture using charge sharing clock scheme is presented. The proposed charge sharing clock generator is able to recover the charge from parasitic-capacitor charging and discharging, so that the dynamic power loss in the pumping process is reduced by a half. To preserve the overlapping period of the four-phase clock used for threshold cancellation technique, two complementary sets of clocks are generated from the proposed clock generator, and each set feeds a certain branch of the dual charge pump to achieve the between-branch charge sharing. A test chip is fabricated in 0.18µm process, and the area penalty of the proposed charge sharing clock generator is 1%. From the measurement results, the proposed charge pump shows an overall power efficiency increase with a peak value of 63.7% comparing to 52.3% of a conventional single charge pump without charge sharing, and the proposed clock scheme shows no degradation on the driving capability while the output ripple voltage is reduced by 43%.

  12. Robust and efficient biometrics based password authentication scheme for telecare medicine information systems using extended chaotic maps.

    PubMed

    Lu, Yanrong; Li, Lixiang; Peng, Haipeng; Xie, Dong; Yang, Yixian

    2015-06-01

    The Telecare Medicine Information Systems (TMISs) provide an efficient communicating platform supporting the patients access health-care delivery services via internet or mobile networks. Authentication becomes an essential need when a remote patient logins into the telecare server. Recently, many extended chaotic maps based authentication schemes using smart cards for TMISs have been proposed. Li et al. proposed a secure smart cards based authentication scheme for TMISs using extended chaotic maps based on Lee's and Jiang et al.'s scheme. In this study, we show that Li et al.'s scheme has still some weaknesses such as violation the session key security, vulnerability to user impersonation attack and lack of local verification. To conquer these flaws, we propose a chaotic maps and smart cards based password authentication scheme by applying biometrics technique and hash function operations. Through the informal and formal security analyses, we demonstrate that our scheme is resilient possible known attacks including the attacks found in Li et al.'s scheme. As compared with the previous authentication schemes, the proposed scheme is more secure and efficient and hence more practical for telemedical environments. PMID:25900328

  13. Robust and efficient biometrics based password authentication scheme for telecare medicine information systems using extended chaotic maps.

    PubMed

    Lu, Yanrong; Li, Lixiang; Peng, Haipeng; Xie, Dong; Yang, Yixian

    2015-06-01

    The Telecare Medicine Information Systems (TMISs) provide an efficient communicating platform supporting the patients access health-care delivery services via internet or mobile networks. Authentication becomes an essential need when a remote patient logins into the telecare server. Recently, many extended chaotic maps based authentication schemes using smart cards for TMISs have been proposed. Li et al. proposed a secure smart cards based authentication scheme for TMISs using extended chaotic maps based on Lee's and Jiang et al.'s scheme. In this study, we show that Li et al.'s scheme has still some weaknesses such as violation the session key security, vulnerability to user impersonation attack and lack of local verification. To conquer these flaws, we propose a chaotic maps and smart cards based password authentication scheme by applying biometrics technique and hash function operations. Through the informal and formal security analyses, we demonstrate that our scheme is resilient possible known attacks including the attacks found in Li et al.'s scheme. As compared with the previous authentication schemes, the proposed scheme is more secure and efficient and hence more practical for telemedical environments.

  14. MODEL OF PHYTOPLANKTON COMPETITION FOR LIMITING AND NONLIMITING NUTRIENTS: IMPLICATIONS FOR DEVELOPMENT OF ESTUARINE AND NEARSHORE MANAGEMENT SCHEMES

    EPA Science Inventory

    The global increase of noxious bloom occurrences has increased the need for phytoplankton management schemes. Such schemes require the ability to predict phytoplankton succession. Equilibrium Resources Competition theory, which is popular for predicting succession in lake systems...

  15. A New Cooperative MIMO Scheme Based on SM for Energy-Efficiency Improvement in Wireless Sensor Network

    PubMed Central

    Peng, Yuyang; Choi, Jaeho

    2014-01-01

    Improving the energy efficiency in wireless sensor networks (WSN) has attracted considerable attention nowadays. The multiple-input multiple-output (MIMO) technique has been proved as a good candidate for improving the energy efficiency, but it may not be feasible in WSN which is due to the size limitation of the sensor node. As a solution, the cooperative multiple-input multiple-output (CMIMO) technique overcomes this constraint and shows a dramatically good performance. In this paper, a new CMIMO scheme based on the spatial modulation (SM) technique named CMIMO-SM is proposed for energy-efficiency improvement. We first establish the system model of CMIMO-SM. Based on this model, the transmission approach is introduced graphically. In order to evaluate the performance of the proposed scheme, a detailed analysis in terms of energy consumption per bit of the proposed scheme compared with the conventional CMIMO is presented. Later, under the guide of this new scheme we extend our proposed CMIMO-SM to a multihop clustered WSN for further achieving energy efficiency by finding an optimal hop-length. Equidistant hop as the traditional scheme will be compared in this paper. Results from the simulations and numerical experiments indicate that by the use of the proposed scheme, significant savings in terms of total energy consumption can be achieved. Combining the proposed scheme with monitoring sensor node will provide a good performance in arbitrary deployed WSN such as forest fire detection system. PMID:24707224

  16. A new cooperative MIMO scheme based on SM for energy-efficiency improvement in wireless sensor network.

    PubMed

    Peng, Yuyang; Choi, Jaeho

    2014-01-01

    Improving the energy efficiency in wireless sensor networks (WSN) has attracted considerable attention nowadays. The multiple-input multiple-output (MIMO) technique has been proved as a good candidate for improving the energy efficiency, but it may not be feasible in WSN which is due to the size limitation of the sensor node. As a solution, the cooperative multiple-input multiple-output (CMIMO) technique overcomes this constraint and shows a dramatically good performance. In this paper, a new CMIMO scheme based on the spatial modulation (SM) technique named CMIMO-SM is proposed for energy-efficiency improvement. We first establish the system model of CMIMO-SM. Based on this model, the transmission approach is introduced graphically. In order to evaluate the performance of the proposed scheme, a detailed analysis in terms of energy consumption per bit of the proposed scheme compared with the conventional CMIMO is presented. Later, under the guide of this new scheme we extend our proposed CMIMO-SM to a multihop clustered WSN for further achieving energy efficiency by finding an optimal hop-length. Equidistant hop as the traditional scheme will be compared in this paper. Results from the simulations and numerical experiments indicate that by the use of the proposed scheme, significant savings in terms of total energy consumption can be achieved. Combining the proposed scheme with monitoring sensor node will provide a good performance in arbitrary deployed WSN such as forest fire detection system.

  17. Resource Allocation and Power Management Schemes in an LTE-Advanced Femtocell Network

    NASA Astrophysics Data System (ADS)

    Lee, Byung-Bog; Yu, Jae-Hak; Lee, In-Hwan; Pyo, Cheol-Sig; Kim, Se-Jin

    In this letter, we introduce two different resource allocation and Tx power management schemes, called resource control and fixed power (RCFP) and fixed resource and power control (FRPC), in an LTE-Advanced femtocell network. We analyze and compare the two schemes in terms of the system throughput for downlink and energy consumption of home evolved NodeB (HeNB) Tx power according to the number of HeNBs and home user equipment (HUE)'s user traffic density (C). The simulation results show that the FRPC scheme has better performance in terms of system throughput for macro user equipments (MUEs) and energy consumption in low C.

  18. A Lightweight Encryption Scheme Combined with Trust Management for Privacy-Preserving in Body Sensor Networks.

    PubMed

    Guo, Ping; Wang, Jin; Ji, Sai; Geng, Xue Hua; Xiong, Neal N

    2015-12-01

    With the pervasiveness of smart phones and the advance of wireless body sensor network (BSN), mobile Healthcare (m-Healthcare), which extends the operation of Healthcare provider into a pervasive environment for better health monitoring, has attracted considerable interest recently. However, the flourish of m-Healthcare still faces many challenges including information security and privacy preservation. In this paper, we propose a secure and privacy-preserving framework combining with multilevel trust management. In our scheme, smart phone resources including computing power and energy can be opportunistically gathered to process the computing-intensive PHI (personal health information) during m-Healthcare emergency with minimal privacy disclosure. In specific, to leverage the PHI privacy disclosure and the high reliability of PHI process and transmission in m-Healthcare emergency, we introduce an efficient lightweight encryption for those users whose trust level is low, which is based on mix cipher algorithms and pair of plain text and cipher texts, and allow a medical user to decide who can participate in the opportunistic computing to assist in processing his overwhelming PHI data. Detailed security analysis and simulations show that the proposed framework can efficiently achieve user-centric privacy protection in m-Healthcare system. PMID:26490148

  19. A Lightweight Encryption Scheme Combined with Trust Management for Privacy-Preserving in Body Sensor Networks.

    PubMed

    Guo, Ping; Wang, Jin; Ji, Sai; Geng, Xue Hua; Xiong, Neal N

    2015-12-01

    With the pervasiveness of smart phones and the advance of wireless body sensor network (BSN), mobile Healthcare (m-Healthcare), which extends the operation of Healthcare provider into a pervasive environment for better health monitoring, has attracted considerable interest recently. However, the flourish of m-Healthcare still faces many challenges including information security and privacy preservation. In this paper, we propose a secure and privacy-preserving framework combining with multilevel trust management. In our scheme, smart phone resources including computing power and energy can be opportunistically gathered to process the computing-intensive PHI (personal health information) during m-Healthcare emergency with minimal privacy disclosure. In specific, to leverage the PHI privacy disclosure and the high reliability of PHI process and transmission in m-Healthcare emergency, we introduce an efficient lightweight encryption for those users whose trust level is low, which is based on mix cipher algorithms and pair of plain text and cipher texts, and allow a medical user to decide who can participate in the opportunistic computing to assist in processing his overwhelming PHI data. Detailed security analysis and simulations show that the proposed framework can efficiently achieve user-centric privacy protection in m-Healthcare system.

  20. Modeling and performance analysis of an improved movement-based location management scheme for packet-switched mobile communication systems.

    PubMed

    Chung, Yun Won; Kwon, Jae Kyun; Park, Suwon

    2014-01-01

    One of the key technologies to support mobility of mobile station (MS) in mobile communication systems is location management which consists of location update and paging. In this paper, an improved movement-based location management scheme with two movement thresholds is proposed, considering bursty data traffic characteristics of packet-switched (PS) services. The analytical modeling for location update and paging signaling loads of the proposed scheme is developed thoroughly and the performance of the proposed scheme is compared with that of the conventional scheme. We show that the proposed scheme outperforms the conventional scheme in terms of total signaling load with an appropriate selection of movement thresholds.

  1. Modeling and Performance Analysis of an Improved Movement-Based Location Management Scheme for Packet-Switched Mobile Communication Systems

    PubMed Central

    Chung, Yun Won; Park, Suwon

    2014-01-01

    One of the key technologies to support mobility of mobile station (MS) in mobile communication systems is location management which consists of location update and paging. In this paper, an improved movement-based location management scheme with two movement thresholds is proposed, considering bursty data traffic characteristics of packet-switched (PS) services. The analytical modeling for location update and paging signaling loads of the proposed scheme is developed thoroughly and the performance of the proposed scheme is compared with that of the conventional scheme. We show that the proposed scheme outperforms the conventional scheme in terms of total signaling load with an appropriate selection of movement thresholds. PMID:24741363

  2. An efficient sparse matrix multiplication scheme for the CYBER 205 computer

    NASA Technical Reports Server (NTRS)

    Lambiotte, Jules J., Jr.

    1988-01-01

    This paper describes the development of an efficient algorithm for computing the product of a matrix and vector on a CYBER 205 vector computer. The desire to provide software which allows the user to choose between the often conflicting goals of minimizing central processing unit (CPU) time or storage requirements has led to a diagonal-based algorithm in which one of four types of storage is selected for each diagonal. The candidate storage types employed were chosen to be efficient on the CYBER 205 for diagonals which have nonzero structure which is dense, moderately sparse, very sparse and short, or very sparse and long; however, for many densities, no diagonal type is most efficient with respect to both resource requirements, and a trade-off must be made. For each diagonal, an initialization subroutine estimates the CPU time and storage required for each storage type based on results from previously performed numerical experimentation. These requirements are adjusted by weights provided by the user which reflect the relative importance the user places on the two resources. The adjusted resource requirements are then compared to select the most efficient storage and computational scheme.

  3. Implementation of a compressive sampling scheme for wireless sensors to achieve energy efficiency in a structural health monitoring system

    NASA Astrophysics Data System (ADS)

    O'Connor, Sean M.; Lynch, Jerome P.; Gilbert, Anna C.

    2013-04-01

    Wireless sensors have emerged to offer low-cost sensors with impressive functionality (e.g., data acquisition, computing, and communication) and modular installations. Such advantages enable higher nodal densities than tethered systems resulting in increased spatial resolution of the monitoring system. However, high nodal density comes at a cost as huge amounts of data are generated, weighing heavy on power sources, transmission bandwidth, and data management requirements, often making data compression necessary. The traditional compression paradigm consists of high rate (>Nyquist) uniform sampling and storage of the entire target signal followed by some desired compression scheme prior to transmission. The recently proposed compressed sensing (CS) framework combines the acquisition and compression stage together, thus removing the need for storage and operation of the full target signal prior to transmission. The effectiveness of the CS approach hinges on the presence of a sparse representation of the target signal in a known basis, similarly exploited by several traditional compressive sensing applications today (e.g., imaging, MRI). Field implementations of CS schemes in wireless SHM systems have been challenging due to the lack of commercially available sensing units capable of sampling methods (e.g., random) consistent with the compressed sensing framework, often moving evaluation of CS techniques to simulation and post-processing. The research presented here describes implementation of a CS sampling scheme to the Narada wireless sensing node and the energy efficiencies observed in the deployed sensors. Of interest in this study is the compressibility of acceleration response signals collected from a multi-girder steel-concrete composite bridge. The study shows the benefit of CS in reducing data requirements while ensuring data analysis on compressed data remain accurate.

  4. An efficient fully unsupervised video object segmentation scheme using an adaptive neural-network classifier architecture.

    PubMed

    Doulamis, A; Doulamis, N; Ntalianis, K; Kollias, S

    2003-01-01

    In this paper, an unsupervised video object (VO) segmentation and tracking algorithm is proposed based on an adaptable neural-network architecture. The proposed scheme comprises: 1) a VO tracking module and 2) an initial VO estimation module. Object tracking is handled as a classification problem and implemented through an adaptive network classifier, which provides better results compared to conventional motion-based tracking algorithms. Network adaptation is accomplished through an efficient and cost effective weight updating algorithm, providing a minimum degradation of the previous network knowledge and taking into account the current content conditions. A retraining set is constructed and used for this purpose based on initial VO estimation results. Two different scenarios are investigated. The first concerns extraction of human entities in video conferencing applications, while the second exploits depth information to identify generic VOs in stereoscopic video sequences. Human face/ body detection based on Gaussian distributions is accomplished in the first scenario, while segmentation fusion is obtained using color and depth information in the second scenario. A decision mechanism is also incorporated to detect time instances for weight updating. Experimental results and comparisons indicate the good performance of the proposed scheme even in sequences with complicated content (object bending, occlusion).

  5. Efficient field-free orientation of CO molecules using a three-step excitation scheme

    NASA Astrophysics Data System (ADS)

    Huang, Yin; Xie, Ting; Wang, Gao-Ren; Han, Yong-Chang; Cong, Shu-Lin

    2013-11-01

    An efficient three-step excitation scheme is proposed to achieve the strong molecular orientation. By taking the CO molecule for example, via the Raman excitation by the femtosecond pulse L 1 and subsequently resonant excitations by a single-cycle THz pulse L 2, the high degree of the field-free orientation of |⟨ cos θ ⟩ |max = 0.8921 can be obtained at the rotational temperature T = 0 K. An additional single-cycle THz pulse L 3 is introduced to further regulate the population distribution on rotational states and decrease the reduction of the orientation originating from the offset phase. With the increase of the central frequency ω 3 of L 3, the optimal |⟨ cos θ ⟩ |max increases monotonically. When ω 3 = 1.0 THz, the degree of the field-free orientation reaches |⟨ cos θ ⟩ |max = 0.9401. Moreover, our scheme is robust against the rotational temperature. Although the molecular orientation weakens with the rise of rotational temperature, |⟨ ⟨ cos θ ⟩ ⟩ | > 0.5 is still obtained until T = 22.8 K.

  6. Efficient congestion control scheme for providing QoS to I-VPN

    NASA Astrophysics Data System (ADS)

    De Marco, Martino; Trabucchi, Sara

    1998-12-01

    In this paper we outline an overall network architecture for the Internet Service Providers who want offer an Internet- Virtual Private Network service with QoS guarantees and, at the same time, with a high-level of efficiency in the network resource usage. The proposed approach is based on the negotiation of a service level agreement, which includes the definition of profile of traffic the user is allowed to emit. The ingress nodes perform an adaptive shaping of the user traffic entering the network, driven by a fast congestion notification scheme. In this scenario, the adoption of a service architecture based on a class-of- service concept enables the Internet Service Provider to offer different level of network performance according to the customer needs.

  7. An efficient approximate factorization implicit scheme for the equations of gasdynamics

    NASA Technical Reports Server (NTRS)

    Barth, T. J.; Steger, J. L.

    1984-01-01

    An efficient implicit finite-difference algorithm for the gas dynamic equations utilizing matrix reduction techniques is presented. A significant reduction in arithmetic operations is achieved while maintaining the same favorable stability characteristics and generality found in the Beam and Warming approximate factorization algorithm. Steady-state solutions to the conservative Euler equations in generalized coordinates are obtained for transonic flows about a NACA 0012 airfoil. The theoretical extension of the matrix reduction technique to the full Navier-Stokes equations in Cartesian coordinates is presented in detail. Linear stability, using a Fourier stability analysis, is demonstrated and discussed for the one-dimensional Euler equations. It is shown that the method offers advantages over the conventional Beam and Warming scheme and can retrofit existing Beam and Warming codes with minimal effort.

  8. An approach for quantifying the efficacy of ecological classification schemes as management tools

    NASA Astrophysics Data System (ADS)

    Flanagan, A. M.; Cerrato, R. M.

    2015-10-01

    Rigorous assessments of ecological classification schemes being applied to submerged environments are needed to evaluate their utility as management tools. Verification that a scheme can quantitatively capture habitat and community variation would be of considerable value to individuals responsible for making difficult management decisions relevant to widespread environmental challenges including those in fisheries, preservation or restoration of critical habitats, and climate change. In this paper, an assessment approach that evaluates a scheme by treating it like a quantitative statistical model is presented. It couples two direct gradient, multivariate statistical techniques, multivariate regression trees (MRT) and redundancy analysis (RDA), with a modelling protocol involving model formulation, model selection, parameter estimation, and measurement of precision to produce a very flexible strategy for analyzing structure in ecological data. To illustrate the proposed approach, the assessment focused on benthic infauna and evaluating the Folk grain size classification scheme, along with some alternative grain size models. Analysis of data sets revealed that while it was fairly easy to uncover biotic-environmental relationships that were over-fitted, the community structure inherent in the data tended to be robustly discernible and preserved across all grain size models, but rigidly parameterized models (i.e., a one size fits all approach for grain size characterization with fixed boundaries) were generally ineffective. The proposed approach provided a clear, detailed, and rigorous assessment of Folk and several alternative models and can be used for the quantitative evaluation of existing ecological classification schemes and/or in the development of new schemes.

  9. An Improvement of Robust and Efficient Biometrics Based Password Authentication Scheme for Telecare Medicine Information Systems Using Extended Chaotic Maps.

    PubMed

    Moon, Jongho; Choi, Younsung; Kim, Jiye; Won, Dongho

    2016-03-01

    Recently, numerous extended chaotic map-based password authentication schemes that employ smart card technology were proposed for Telecare Medical Information Systems (TMISs). In 2015, Lu et al. used Li et al.'s scheme as a basis to propose a password authentication scheme for TMISs that is based on biometrics and smart card technology and employs extended chaotic maps. Lu et al. demonstrated that Li et al.'s scheme comprises some weaknesses such as those regarding a violation of the session-key security, a vulnerability to the user impersonation attack, and a lack of local verification. In this paper, however, we show that Lu et al.'s scheme is still insecure with respect to issues such as a violation of the session-key security, and that it is vulnerable to both the outsider attack and the impersonation attack. To overcome these drawbacks, we retain the useful properties of Lu et al.'s scheme to propose a new password authentication scheme that is based on smart card technology and requires the use of chaotic maps. Then, we show that our proposed scheme is more secure and efficient and supports security properties.

  10. An Improvement of Robust and Efficient Biometrics Based Password Authentication Scheme for Telecare Medicine Information Systems Using Extended Chaotic Maps.

    PubMed

    Moon, Jongho; Choi, Younsung; Kim, Jiye; Won, Dongho

    2016-03-01

    Recently, numerous extended chaotic map-based password authentication schemes that employ smart card technology were proposed for Telecare Medical Information Systems (TMISs). In 2015, Lu et al. used Li et al.'s scheme as a basis to propose a password authentication scheme for TMISs that is based on biometrics and smart card technology and employs extended chaotic maps. Lu et al. demonstrated that Li et al.'s scheme comprises some weaknesses such as those regarding a violation of the session-key security, a vulnerability to the user impersonation attack, and a lack of local verification. In this paper, however, we show that Lu et al.'s scheme is still insecure with respect to issues such as a violation of the session-key security, and that it is vulnerable to both the outsider attack and the impersonation attack. To overcome these drawbacks, we retain the useful properties of Lu et al.'s scheme to propose a new password authentication scheme that is based on smart card technology and requires the use of chaotic maps. Then, we show that our proposed scheme is more secure and efficient and supports security properties. PMID:26743628

  11. An efficient parallel implementation of explicit multirate Runge–Kutta schemes for discontinuous Galerkin computations

    SciTech Connect

    Seny, Bruno Lambrechts, Jonathan; Toulorge, Thomas; Legat, Vincent; Remacle, Jean-François

    2014-01-01

    Although explicit time integration schemes require small computational efforts per time step, their efficiency is severely restricted by their stability limits. Indeed, the multi-scale nature of some physical processes combined with highly unstructured meshes can lead some elements to impose a severely small stable time step for a global problem. Multirate methods offer a way to increase the global efficiency by gathering grid cells in appropriate groups under local stability conditions. These methods are well suited to the discontinuous Galerkin framework. The parallelization of the multirate strategy is challenging because grid cells have different workloads. The computational cost is different for each sub-time step depending on the elements involved and a classical partitioning strategy is not adequate any more. In this paper, we propose a solution that makes use of multi-constraint mesh partitioning. It tends to minimize the inter-processor communications, while ensuring that the workload is almost equally shared by every computer core at every stage of the algorithm. Particular attention is given to the simplicity of the parallel multirate algorithm while minimizing computational and communication overheads. Our implementation makes use of the MeTiS library for mesh partitioning and the Message Passing Interface for inter-processor communication. Performance analyses for two and three-dimensional practical applications confirm that multirate methods preserve important computational advantages of explicit methods up to a significant number of processors.

  12. Extension of the TDCR model to compute counting efficiencies for radionuclides with complex decay schemes.

    PubMed

    Kossert, K; Cassette, Ph; Carles, A Grau; Jörg, G; Gostomski, Christroph Lierse V; Nähle, O; Wolf, Ch

    2014-05-01

    The triple-to-double coincidence ratio (TDCR) method is frequently used to measure the activity of radionuclides decaying by pure β emission or electron capture (EC). Some radionuclides with more complex decays have also been studied, but accurate calculations of decay branches which are accompanied by many coincident γ transitions have not yet been investigated. This paper describes recent extensions of the model to make efficiency computations for more complex decay schemes possible. In particular, the MICELLE2 program that applies a stochastic approach of the free parameter model was extended. With an improved code, efficiencies for β(-), β(+) and EC branches with up to seven coincident γ transitions can be calculated. Moreover, a new parametrization for the computation of electron stopping powers has been implemented to compute the ionization quenching function of 10 commercial scintillation cocktails. In order to demonstrate the capabilities of the TDCR method, the following radionuclides are discussed: (166m)Ho (complex β(-)/γ), (59)Fe (complex β(-)/γ), (64)Cu (β(-), β(+), EC and EC/γ) and (229)Th in equilibrium with its progenies (decay chain with many α, β and complex β(-)/γ transitions).

  13. An efficient parallel implementation of explicit multirate Runge-Kutta schemes for discontinuous Galerkin computations

    NASA Astrophysics Data System (ADS)

    Seny, Bruno; Lambrechts, Jonathan; Toulorge, Thomas; Legat, Vincent; Remacle, Jean-François

    2014-01-01

    Although explicit time integration schemes require small computational efforts per time step, their efficiency is severely restricted by their stability limits. Indeed, the multi-scale nature of some physical processes combined with highly unstructured meshes can lead some elements to impose a severely small stable time step for a global problem. Multirate methods offer a way to increase the global efficiency by gathering grid cells in appropriate groups under local stability conditions. These methods are well suited to the discontinuous Galerkin framework. The parallelization of the multirate strategy is challenging because grid cells have different workloads. The computational cost is different for each sub-time step depending on the elements involved and a classical partitioning strategy is not adequate any more. In this paper, we propose a solution that makes use of multi-constraint mesh partitioning. It tends to minimize the inter-processor communications, while ensuring that the workload is almost equally shared by every computer core at every stage of the algorithm. Particular attention is given to the simplicity of the parallel multirate algorithm while minimizing computational and communication overheads. Our implementation makes use of the MeTiS library for mesh partitioning and the Message Passing Interface for inter-processor communication. Performance analyses for two and three-dimensional practical applications confirm that multirate methods preserve important computational advantages of explicit methods up to a significant number of processors.

  14. Efficient real gas Navier-Stokes computations of high speed flows using an LU scheme

    NASA Technical Reports Server (NTRS)

    Coirier, William J.

    1990-01-01

    An efficient method to account for the chemically frozen thermodynamic and transport properties of air in three dimensional Navier-Stokes calculations was demonstrated. This approach uses an explicitly specified equation of state (EOS) so that the fluid pressure, temperature and transport properties are directly related to the flow variables. Since the pressure is explicitly known as a general function of the flow variables no assumptions are made regarding the pressure derivatives in the construction of the flux Jacobians. The method is efficient since no sub-iterations are required to deduce the pressure and temperature from the flux variables and allows different equations of state to be easily supplied to the code. The flexibility of the EOS approach is demonstrated by implementing a high order TVD upwinding scheme based upon flux differencing and Van Leer's flux vector splitting. The EOS approach is demonstrated by computing the hypersonic flow through the corner region of two mutually perpendicular flat plates and through a simplified model of a scramjet module gap-seal configuration.

  15. Efficient Pumping Schemes for High Average Brightness Collisional X-ray Lasers

    SciTech Connect

    Keenan, R; Dunn, J; Shlyaptsev, V N; Smith, R F; Patel, P K; Price, D F

    2003-10-07

    Advances in transient collisional x-ray lasers have been demonstrated over the last 5 years as a technique for achieving tabletop soft x-ray lasers using 2-10 J of laser pump energy. The high peak brightness of these sources operating in the high output saturation regime, in the range of 10{sup 24}-10{sup 25} ph. mm{sup -2} mrad{sup -2} s-1 (0.1% BW){sup -1}, is ideal for many applications requiring high photon fluence in a single short burst. However, the pump energy required for these x-ray lasers is still relatively high and limits the x-ray laser repetition rate to 1 shot every few minutes. Higher repetition rate collisional schemes have been reported and show some promise for high output in the future. We report a novel technique for enhancing the coupling efficiency of the laser pump into the gain medium that could lead to enhanced x-ray inversion with a factor of ten reduction in the drive energy. This has been applied to the collisional excitation scheme for Ni-like Mo at 18.9 nm and x-ray laser output has been demonstrated. Preliminary results show lasing on a single shot of the optical laser operating at 10 Hz and with 70 mJ in the short pulse. Such a proposed source would have higher average brightness, {approx}10{sup 14} ph. mm{sup -2} mrad{sup -2} s{sup -1} (0.1% BW){sup -1}, than present bending magnet 3rd generation synchrotron sources operating at the same spectral range.

  16. Assessing the efficiency gains of improved spatial targeting of policy interventions; the example of an agri-environmental scheme.

    PubMed

    van der Horst, Dan

    2007-12-01

    GIS-based spatial targeting is increasingly recognised as a potentially useful tool to design more efficient policy interventions. The use of this tool has also been advocated in the context of incentive-based agri-environmental schemes, but there has been little work to date to estimate the level of efficiency gains which it may help to achieve. This paper investigates the requirements to arrive at such estimates, using a Scottish farm woodland scheme as a case study. This agri-environmental scheme aims to provide visual amenity and biodiversity. Maps of these two benefits are used to develop improved spatial targeting scenarios that deliver significant efficiency gains in comparison to the existing scheme design. The paper discusses the nature of the spatial distribution of the relevant benefits at the landscape scale and the data requirements for the realistic estimation of efficiency gains. It concludes that although much work needs to be done, the methods available today could and should play a much greater role in improving the landscape-scale design of existing land use schemes focused on the delivery of non-market benefits. PMID:17350157

  17. Efficient architectures for two-dimensional discrete wavelet transform using lifting scheme.

    PubMed

    Xiong, Chengyi; Tian, Jinwen; Liu, Jian

    2007-03-01

    Novel architectures for 1-D and 2-D discrete wavelet transform (DWT) by using lifting schemes are presented in this paper. An embedded decimation technique is exploited to optimize the architecture for 1-D DWT, which is designed to receive an input and generate an output with the low- and high-frequency components of original data being available alternately. Based on this 1-D DWT architecture, an efficient line-based architecture for 2-D DWT is further proposed by employing parallel and pipeline techniques, which is mainly composed of two horizontal filter modules and one vertical filter module, working in parallel and pipeline fashion with 100% hardware utilization. This 2-D architecture is called fast architecture (FA) that can perform J levels of decomposition for N * N image in approximately 2N2(1 - 4(-J))/3 internal clock cycles. Moreover, another efficient generic line-based 2-D architecture is proposed by exploiting the parallelism among four subband transforms in lifting-based 2-D DWT, which can perform J levels of decomposition for N * N image in approximately N2(1 - 4(-J))/3 internal clock cycles; hence, it is called high-speed architecture. The throughput rate of the latter is increased by two times when comparing with the former 2-D architecture, but only less additional hardware cost is added. Compared with the works reported in previous literature, the proposed architectures for 2-D DWT are efficient alternatives in tradeoff among hardware cost, throughput rate, output latency and control complexity, etc. PMID:17357722

  18. Consolidating the social health insurance schemes in China: towards an equitable and efficient health system.

    PubMed

    Meng, Qingyue; Fang, Hai; Liu, Xiaoyun; Yuan, Beibei; Xu, Jin

    2015-10-10

    Fragmentation in social health insurance schemes is an important factor for inequitable access to health care and financial protection for people covered by different health insurance schemes in China. To fulfil its commitment of universal health coverage by 2020, the Chinese Government needs to prioritise addressing this issue. After analysing the situation of fragmentation, this Review summarises efforts to consolidate health insurance schemes both in China and internationally. Rural migrants, elderly people, and those with non-communicable diseases in China will greatly benefit from consolidation of the existing health insurance schemes with extended funding pools, thereby narrowing the disparities among health insurance schemes in fund level and benefit package. Political commitments, institutional innovations, and a feasible implementation plan are the major elements needed for success in consolidation. Achievement of universal health coverage in China needs systemic strategies including consolidation of the social health insurance schemes.

  19. Augmented Z scheme blueprint for efficient solar water splitting system using quaternary chalcogenide absorber material.

    PubMed

    Sarswat, Prashant K; Bhattacharyya, Dhiman; Free, Michael L; Misra, Mano

    2016-02-01

    Photoelectrochemical hydrogen (H2) production from water is a key method of addressing energy needs using an environmentally friendly approach. In the last two decades we have witnessed the evolution of many different expensive catalysts, photoelectrodes and related technologies, especially those involving precious metals and use of acidic or basic electrolytes for hydrogen production. Cu2ZnSnS4 (CZTS) is a relatively new candidate in the category of efficient photocathodes, due to its high absorption coefficient and near optimal energy band gap. In this paper, we demonstrate photoelectrochemical viability of CZTS in combination with other photoanodes such as TiO2, BiVO4, and WO3 for H2 production with the use of an electrolyte of near neutral pH, a single redox mediator, and insignificant potential biasing. A systematic study was performed to understand CZTS performance with each photoanode, band energetics of CZTS with other photoanodes, impedance behavior of each photoelectrode, and utility of a CZTS photocell in place of a CZTS photocathode. Our assessment indicates that a protected CZTS photocell performs well when used in a Z-scheme containing TiO2 nanotubular array-CZTS or nanocrystalline WO3-CZTS. Preliminary experiments indicated that apart from band energetics, porosity and effective surface area of the photoanodes play a crucial role in determining the photoelectrochemical performance of the system. PMID:26762553

  20. Unified computational framework for the efficient solution of n-field coupled problems with monolithic schemes

    NASA Astrophysics Data System (ADS)

    Verdugo, Francesc; Wall, Wolfgang A.

    2016-10-01

    In this paper, we propose and evaluate the performance of a unified computational framework for preconditioning systems of linear equations resulting from the solution of coupled problems with monolithic schemes. The framework is composed by promising application-specific preconditioners presented previously in the literature with the common feature that they are able to be implemented for a generic coupled problem, involving an arbitrary number of fields, and to be used to solve a variety of applications. The first selected preconditioner is based on a generic block Gauss-Seidel iteration for uncoupling the fields, and standard algebraic multigrid (AMG) methods for solving the resulting uncoupled problems. The second preconditioner is based on the semi-implicit method for pressure-linked equations (SIMPLE) which is extended here to deal with an arbitrary number of fields, and also results in uncoupled problems that can be solved with standard AMG. Finally, a more sophisticated preconditioner is considered which enforces the coupling at all AMG levels, in contrast to the other two techniques which resolve the coupling only at the finest level. Our purpose is to show that these methods perform satisfactory in quite different scenarios apart from their original applications. To this end, we consider three very different coupled problems: thermo-structure interaction, fluid-structure interaction and a complex model of the human lung. Numerical results show that these general purpose methods are efficient and scalable in this range of applications.

  1. An efficient scheme for sampling fast dynamics at a low average data acquisition rate.

    PubMed

    Philippe, A; Aime, S; Roger, V; Jelinek, R; Prévot, G; Berthier, L; Cipelletti, L

    2016-02-24

    We introduce a temporal scheme for data sampling, based on a variable delay between two successive data acquisitions. The scheme is designed so as to reduce the average data flow rate, while still retaining the information on the data evolution on fast time scales. The practical implementation of the scheme is discussed and demonstrated in light scattering and microscopy experiments that probe the dynamics of colloidal suspensions using CMOS or CCD cameras as detectors.

  2. Analysis and performance assessment of a fragment retransmission scheme for energy efficient IEEE 802.11 WLANs.

    PubMed

    Mafole, Prosper; Aritsugi, Masayoshi

    2016-01-01

    Backoff-free fragment retransmission (BFFR) scheme enhances the performance of legacy MAC layer fragmentation by eliminating contention overhead. The eliminated overhead is the result of backoff executed before a retransmission attempt is made when fragment transmission failure occurs within a fragment burst. This paper provides a mathematical analysis of BFFR energy efficiency and further assesses, by means of simulations, the energy efficiency, throughput and delay obtained when BFFR is used. The validity of the new scheme is evaluated in different scenarios namely, constant bit rate traffic, realistic bursty internet traffic, node mobility, rigid and elastic flows and their combinations at different traffic loads. We also evaluate and discuss the impact of BFFR on MAC fairness when the number of nodes is varied from 4 to 10. It is shown that BFFR has advantages over legacy MAC fragmentation scheme in all the scenarios.

  3. Efficient compression scheme by use of the region division of elemental images on MALT in three-dimensional integral imaging

    NASA Astrophysics Data System (ADS)

    Kang, Ho-Hyun; Lee, Jung-Woo; Shin, Dong-Hak; Kim, Eun-Soo

    2010-02-01

    This paper addresses the efficient compression scheme of elemental image array (EIA) generated from the moving array lenslet technique (MALT) based on MPEG-4. The EIAs are picked-up by MALT controlling the spatial ray sampling of ray and which produces few EIAs that the positions of the lenslet arrays are rapidly vibrated in the lateral directions within the retention time of the afterimage of human eye. To enhance the similarity in each EIA picked-up by MALT, several EIAs obtained from MALT are regenerated by the collection of an elemental image occupied at the same position in each EIA. The newly generated each EIA has high similarity among adjacent elemental images. To illustrate the feasibility of the proposed scheme, some experiments are carried out to show the increased compression efficiency and we obtained the improved compression ratio of 12% compared to the unhandled compression scheme.

  4. Analysis and performance assessment of a fragment retransmission scheme for energy efficient IEEE 802.11 WLANs.

    PubMed

    Mafole, Prosper; Aritsugi, Masayoshi

    2016-01-01

    Backoff-free fragment retransmission (BFFR) scheme enhances the performance of legacy MAC layer fragmentation by eliminating contention overhead. The eliminated overhead is the result of backoff executed before a retransmission attempt is made when fragment transmission failure occurs within a fragment burst. This paper provides a mathematical analysis of BFFR energy efficiency and further assesses, by means of simulations, the energy efficiency, throughput and delay obtained when BFFR is used. The validity of the new scheme is evaluated in different scenarios namely, constant bit rate traffic, realistic bursty internet traffic, node mobility, rigid and elastic flows and their combinations at different traffic loads. We also evaluate and discuss the impact of BFFR on MAC fairness when the number of nodes is varied from 4 to 10. It is shown that BFFR has advantages over legacy MAC fragmentation scheme in all the scenarios. PMID:27610322

  5. Efficient Low Dissipative High Order Schemes for Multiscale MHD Flows, I: Basic Theory

    NASA Technical Reports Server (NTRS)

    Sjoegreen, Bjoern; Yee, H. C.

    2003-01-01

    The objective of this paper is to extend our recently developed highly parallelizable nonlinear stable high order schemes for complex multiscale hydrodynamic applications to the viscous MHD equations. These schemes employed multiresolution wavelets as adaptive numerical dissipation controls t o limit the amount of and to aid the selection and/or blending of the appropriate types of dissipation to be used. The new scheme is formulated for both the conservative and non-conservative form of the MHD equations in curvilinear grids. The four advantages of the present approach over existing MHD schemes reported in the open literature are as follows. First, the scheme is constructed for long-time integrations of shock/turbulence/combustion MHD flows. Available schemes are too diffusive for long-time integrations and/or turbulence/combustion problems. Second, unlike exist- ing schemes for the conservative MHD equations which suffer from ill-conditioned eigen- decompositions, the present scheme makes use of a well-conditioned eigen-decomposition obtained from a minor modification of the eigenvectors of the non-conservative MHD equations t o solve the conservative form of the MHD equations. Third, this approach of using the non-conservative eigensystem when solving the conservative equations also works well in the context of standard shock-capturing schemes for the MHD equations. Fourth, a new approach to minimize the numerical error of the divergence-free magnetic condition for high order schemes is introduced. Numerical experiments with typical MHD model problems revealed the applicability of the newly developed schemes for the MHD equations.

  6. Dynamic Key Management Schemes for Secure Group Access Control Using Hierarchical Clustering in Mobile Ad Hoc Networks

    NASA Astrophysics Data System (ADS)

    Tsaur, Woei-Jiunn; Pai, Haw-Tyng

    2008-11-01

    The applications of group computing and communication motivate the requirement to provide group access control in mobile ad hoc networks (MANETs). The operation in MANETs' groups performs a decentralized manner and accommodated membership dynamically. Moreover, due to lack of centralized control, MANETs' groups are inherently insecure and vulnerable to attacks from both within and outside the groups. Such features make access control more challenging in MANETs. Recently, several researchers have proposed group access control mechanisms in MANETs based on a variety of threshold signatures. However, these mechanisms cannot actually satisfy MANETs' dynamic environments. This is because the threshold-based mechanisms cannot be achieved when the number of members is not up to the threshold value. Hence, by combining the efficient elliptic curve cryptosystem, self-certified public key cryptosystem and secure filter technique, we construct dynamic key management schemes based on hierarchical clustering for securing group access control in MANETs. Specifically, the proposed schemes can constantly accomplish secure group access control only by renewing the secure filters of few cluster heads, when a cluster head joins or leaves a cross-cluster. In such a new way, we can find that the proposed group access control scheme can be very effective for securing practical applications in MANETs.

  7. Exploring efficiencies of SISO, multi-SISO, and MIMO AVC schemes for floor vibration control

    NASA Astrophysics Data System (ADS)

    Nyawako, Donald S.; Reynolds, Paul; Hudson, Malcolm J.

    2012-04-01

    Continued advancements in steel and concrete materials as well as improved computer-optimized designs are resulting in more efficient floor structures, which have longer spans and are more lightweight. In addition, there is a tendency for offices to be more open-plan with fewer internal partitions. These structures possess low and closely spaced natural frequencies, sometimes falling within the range of frequencies produced by human activities, as well as low damping levels. Vibration serviceability problems are thus arising more frequently than before. The tendency for developers to require floor structures suitable for a variety of types of occupation so as to increase their economic viability also has clear ramifications for their vibration serviceability. Active vibration control (AVC) is emerging as a viable technology for mitigation of human-induced vibrations in problem floors. Past AVC research work, as demonstrated in analytical studies and successfully implemented in field trials, have focused predominantly on collocated sensor and actuator pairs in SISO or multi-SISO direct-output feedback schemes, for example, direct velocity feedback (DVF). This paper demonstrates the potential benefits that may be derived from using model-based control approaches, for example, in isolating and controlling specific problematic frequencies only. The approaches investigated here comprise of independent modal space control (IMSC) and pole-placement controllers that are implemented in SISO, SIMO, and MIMO control structures. Both the analytical and experimental studies presented are based on a laboratory structure. Attenuations in target modes of vibration ranged between 15.0-27.0 dB in the analytical studies and experimental implementation for all the controllers studied. Further, both analytical studies and experimental implementation yielded a 70-89 % reduction in acceleration responses from two different walking frequencies.

  8. The role of agri-environment schemes in conservation and environmental management.

    PubMed

    Batáry, Péter; Dicks, Lynn V; Kleijn, David; Sutherland, William J

    2015-08-01

    Over half of the European landscape is under agricultural management and has been for millennia. Many species and ecosystems of conservation concern in Europe depend on agricultural management and are showing ongoing declines. Agri-environment schemes (AES) are designed partly to address this. They are a major source of nature conservation funding within the European Union (EU) and the highest conservation expenditure in Europe. We reviewed the structure of current AES across Europe. Since a 2003 review questioned the overall effectiveness of AES for biodiversity, there has been a plethora of case studies and meta-analyses examining their effectiveness. Most syntheses demonstrate general increases in farmland biodiversity in response to AES, with the size of the effect depending on the structure and management of the surrounding landscape. This is important in the light of successive EU enlargement and ongoing reforms of AES. We examined the change in effect size over time by merging the data sets of 3 recent meta-analyses and found that schemes implemented after revision of the EU's agri-environmental programs in 2007 were not more effective than schemes implemented before revision. Furthermore, schemes aimed at areas out of production (such as field margins and hedgerows) are more effective at enhancing species richness than those aimed at productive areas (such as arable crops or grasslands). Outstanding research questions include whether AES enhance ecosystem services, whether they are more effective in agriculturally marginal areas than in intensively farmed areas, whether they are more or less cost-effective for farmland biodiversity than protected areas, and how much their effectiveness is influenced by farmer training and advice? The general lesson from the European experience is that AES can be effective for conserving wildlife on farmland, but they are expensive and need to be carefully designed and targeted.

  9. The role of agri-environment schemes in conservation and environmental management.

    PubMed

    Batáry, Péter; Dicks, Lynn V; Kleijn, David; Sutherland, William J

    2015-08-01

    Over half of the European landscape is under agricultural management and has been for millennia. Many species and ecosystems of conservation concern in Europe depend on agricultural management and are showing ongoing declines. Agri-environment schemes (AES) are designed partly to address this. They are a major source of nature conservation funding within the European Union (EU) and the highest conservation expenditure in Europe. We reviewed the structure of current AES across Europe. Since a 2003 review questioned the overall effectiveness of AES for biodiversity, there has been a plethora of case studies and meta-analyses examining their effectiveness. Most syntheses demonstrate general increases in farmland biodiversity in response to AES, with the size of the effect depending on the structure and management of the surrounding landscape. This is important in the light of successive EU enlargement and ongoing reforms of AES. We examined the change in effect size over time by merging the data sets of 3 recent meta-analyses and found that schemes implemented after revision of the EU's agri-environmental programs in 2007 were not more effective than schemes implemented before revision. Furthermore, schemes aimed at areas out of production (such as field margins and hedgerows) are more effective at enhancing species richness than those aimed at productive areas (such as arable crops or grasslands). Outstanding research questions include whether AES enhance ecosystem services, whether they are more effective in agriculturally marginal areas than in intensively farmed areas, whether they are more or less cost-effective for farmland biodiversity than protected areas, and how much their effectiveness is influenced by farmer training and advice? The general lesson from the European experience is that AES can be effective for conserving wildlife on farmland, but they are expensive and need to be carefully designed and targeted. PMID:25997591

  10. Efficient priority encoding transmission scheme based Wyner-Ziv coding and spatial scalability

    NASA Astrophysics Data System (ADS)

    Ramon, Marie; Coudoux, Francois-Xavier; Gazalet, Marc-Georges

    2005-07-01

    We present an original digital video transmission scheme based on Wyner-Ziv coding. The proposed scheme is derived from the previous work described in Reference4. In this case, the Forward Error Protection (FEP) scheme applies the general framework of systematic lossy source-channel coding to constitute the Wyner-Ziv description based on a coarse description of the transmitted sequence. In the present work, we propose to generate the supplementary bit stream from a low spatial resolution version of the transmitted video signal. The corresponding Wyner-Ziv description is used at the decoder in order to insure error free reconstruction of the base layer. First, we give an overview of error resilience techniques previously developed for robust video transmission. In particular, the systematic lossy error protection scheme in 4 is presented. Then the proposed transmission scheme is described. Preliminary results are finally presented in order to illustrate the interest of the proposed scheme. Further work and perspectives are also discussed.

  11. Efficient construction of high-resolution TVD conservative schemes for equations with source terms: application to shallow water flows

    NASA Astrophysics Data System (ADS)

    Burguete, J.; García-Navarro, P.

    2001-09-01

    High-resolution total variation diminishing (TVD) schemes are widely used for the numerical approximation of hyperbolic conservation laws. Their extension to equations with source terms involving spatial derivatives is not obvious. In this work, efficient ways of constructing conservative schemes from the conservative, non-conservative or characteristic form of the equations are described in detail. An upwind, as opposed to a pointwise, treatment of the source terms is adopted here, and a new technique is proposed in which source terms are included in the flux limiter functions to get a complete second-order compact scheme. A new correction to fix the entropy problem is also presented and a robust treatment of the boundary conditions according to the discretization used is stated. Copyright

  12. Efficient Scheme for Macroscopic Superpositions and Entanglement of High-Order Squeezed Vacuum States in Cavity QED

    NASA Astrophysics Data System (ADS)

    Chen, Chang-Yong

    2008-05-01

    We propose an efficient scheme for generating the macroscopic superpositions and the entanglement between the high-order squeezed vacuum states by considering the multi-photon interaction of N two-level atoms in a cavity with high quality factor, assisted by a strong driving field. Through specific choices of the cavity detuning, a number of multi-party entangled states between the atoms and the high-order squeezed vacuum states and among the high-order squeezed vacuum states of the cavities can be prepared, including also the macroscopic "Schrödinger cats" of the high-order squeezed vacuum states, the entangled states of the macroscopic "Schrödinger cats", and so on. Possible extension and application of our scheme are discussed. Our scheme is reachable within the current techniques in the cavity QED.

  13. Design and simulation of a fuel cell hybrid emergency power system for a more electric aircraft: Evaluation of energy management schemes

    NASA Astrophysics Data System (ADS)

    Njoya Motapon, Souleman

    . The energy management schemes are compared based on the following criteria: the hydrogen consumption, the state of charges of the batteries and supercapacitors and the overall system efficiency. Moreover the stress on each energy source, which impacts their life cycle, are measured using a new approach based on the wavelet transform of their instantaneous power. A simulation model and an experimental test bench are developed to validate all analysis and performances. The main results obtained are as follows: the state machine control scheme provided a slightly better efficiency and stresses on the batteries and supercapacitors. The classical PI control and the proposed scheme had the lowest fuel consumption and more use of the battery energy. As expected, the lowest fuel cell stress and lowest use of the battery energy was achieved with the frequency decoupling and fuzzy logic scheme, but at the expense of more fuel consumption and lower overall efficiency. The DC bus or supercapacitor voltage was maintained nearly constant for all the schemes. Also, the proposed strategy performed slightly better than the ECMS in terms of efficiency and fuel consumption, with an increase in fuel economy by 3 %. The energy management scheme suitable for a MEA emergency system should be a multischeme EMS such that each scheme is chosen based on a specific criterion to prioritize. As an example, depending on the operating life of each energy source, the energy management strategy can be chosen to either minimise the stress on the fuel cell system, the battery system or supercapacitor system, hence maximizing the life cycle of the hybrid power system. Also if the target is to reduce the fuel consumption, the proposed or the classical PI strategies are better alternatives.

  14. Fiber-optic integration and efficient detection schemes for optomechanical resonators

    NASA Astrophysics Data System (ADS)

    Cohen, Justin D.

    optomechanical resonators to optical fibers, with an emphasis on fabrication processes and optical characterization. I will then proceed to describe a few experiments enabled by the fiber couplers. The first studies the performance of an optomechanical resonator as a precise sensor for continuous position measurement. The sensitivity of the measurement, limited by the detection efficiency of intracavity photons, is compared to the standard quantum limit imposed by the quantum properties of the laser probe light. The added noise of the measurement is seen to fall within a factor of 3 of the standard quantum limit, representing an order of magnitude improvement over previous experiments utilizing optomechanical crystals, and matching the performance of similar measurements in the microwave domain. The next experiment uses single photon counting to detect individual phonon emission and absorption events within the nanomechanical oscillator. The scattering of laser light from mechanical motion produces correlated photon-phonon pairs, and detection of the emitted photon corresponds to an effective phonon counting scheme. In the process of scattering, the coherence properties of the mechanical oscillation are mapped onto the reflected light. Intensity interferometry of the reflected light then allows measurement of the temporal coherence of the acoustic field. These correlations are measured for a range of experimental conditions, including the optomechanical amplification of the mechanics to a self-oscillation regime, and comparisons are drawn to a laser system for phonons. Finally, prospects for using phonon counting and intensity interferometry to produce non-classical mechanical states are detailed following recent proposals in literature.

  15. An energy-efficient and compact clustering scheme with temporary support nodes for cognitive radio sensor networks.

    PubMed

    Salim, Shelly; Moh, Sangman; Choi, Dongmin; Chung, Ilyong

    2014-01-01

    A cognitive radio sensor network (CRSN) is a wireless sensor network whose sensor nodes are equipped with cognitive radio capability. Clustering is one of the most challenging issues in CRSNs, as all sensor nodes, including the cluster head, have to use the same frequency band in order to form a cluster. However, due to the nature of heterogeneous channels in cognitive radio, it is difficult for sensor nodes to find a cluster head. This paper proposes a novel energy-efficient and compact clustering scheme named clustering with temporary support nodes (CENTRE). CENTRE efficiently achieves a compact cluster formation by adopting two-phase cluster formation with fixed duration. By introducing a novel concept of temporary support nodes to improve the cluster formation, the proposed scheme enables sensor nodes in a network to find a cluster head efficiently. The performance study shows that not only is the clustering process efficient and compact but it also results in remarkable energy savings that prolong the overall network lifetime. In addition, the proposed scheme decreases both the clustering overhead and the average distance between cluster heads and their members. PMID:25116905

  16. An Energy-Efficient and Compact Clustering Scheme with Temporary Support Nodes for Cognitive Radio Sensor Networks

    PubMed Central

    Salim, Shelly; Moh, Sangman; Choi, Dongmin; Chung, Ilyong

    2014-01-01

    A cognitive radio sensor network (CRSN) is a wireless sensor network whose sensor nodes are equipped with cognitive radio capability. Clustering is one of the most challenging issues in CRSNs, as all sensor nodes, including the cluster head, have to use the same frequency band in order to form a cluster. However, due to the nature of heterogeneous channels in cognitive radio, it is difficult for sensor nodes to find a cluster head. This paper proposes a novel energy-efficient and compact clustering scheme named clustering with temporary support nodes (CENTRE). CENTRE efficiently achieves a compact cluster formation by adopting two-phase cluster formation with fixed duration. By introducing a novel concept of temporary support nodes to improve the cluster formation, the proposed scheme enables sensor nodes in a network to find a cluster head efficiently. The performance study shows that not only is the clustering process efficient and compact but it also results in remarkable energy savings that prolong the overall network lifetime. In addition, the proposed scheme decreases both the clustering overhead and the average distance between cluster heads and their members. PMID:25116905

  17. An energy-efficient and compact clustering scheme with temporary support nodes for cognitive radio sensor networks.

    PubMed

    Salim, Shelly; Moh, Sangman; Choi, Dongmin; Chung, Ilyong

    2014-08-11

    A cognitive radio sensor network (CRSN) is a wireless sensor network whose sensor nodes are equipped with cognitive radio capability. Clustering is one of the most challenging issues in CRSNs, as all sensor nodes, including the cluster head, have to use the same frequency band in order to form a cluster. However, due to the nature of heterogeneous channels in cognitive radio, it is difficult for sensor nodes to find a cluster head. This paper proposes a novel energy-efficient and compact clustering scheme named clustering with temporary support nodes (CENTRE). CENTRE efficiently achieves a compact cluster formation by adopting two-phase cluster formation with fixed duration. By introducing a novel concept of temporary support nodes to improve the cluster formation, the proposed scheme enables sensor nodes in a network to find a cluster head efficiently. The performance study shows that not only is the clustering process efficient and compact but it also results in remarkable energy savings that prolong the overall network lifetime. In addition, the proposed scheme decreases both the clustering overhead and the average distance between cluster heads and their members.

  18. Hydro-geomorphic approaches to designing nature-based flood and drought management schemes

    NASA Astrophysics Data System (ADS)

    Hetherington, David; Large, Andy; Quinn, Paul

    2016-04-01

    The need for nature-based solutions to runoff management is more pressing than ever. If it is possible to calculate how much water needs to be managed and where the opportunities are in the landscape, then it would be a significant step forward in water resources management. Here we will show how basic hydro-geomorphic indices can guide a catchment manager in identifying the types of intervention that are appropriate at different scales. Using runoff management zones can provide key ecosystems services that make the whole catchment system function better. The key indicators are: a) The Topographic Wetness Index, for use in small catchment and on hillslopes for identifying overland flow pathways that can be managed to store and disconnect fast runoff; b) Strahler stream order to show which small channels can be directly managed to slow, store and filter flow and c) Geomorphic Indices that estimate the floodplain extent, related to stream order, where flood storage zones could be created to hold back large amounts of water. Estimating how much flood water and sediment can be managed by the addition of runoff attenuation features in a landscape could be very important to policy makers. If enough water can be stored in small, medium and extreme events, then the more severe issues of floods, pollution and drought could potentially be addressed, obviating calls for ever bigger and more complex flood protection schemes.

  19. An Efficient Method for Detecting Misbehaving Zone Manager in MANET

    NASA Astrophysics Data System (ADS)

    Rafsanjani, Marjan Kuchaki; Pakzad, Farzaneh; Asadinia, Sanaz

    In recent years, one of the wireless technologies increased tremendously is mobile ad hoc networks (MANETs) in which mobile nodes organize themselves without the help of any predefined infrastructure. MANETs are highly vulnerable to attack due to the open medium, dynamically changing network topology, cooperative algorithms, lack of centralized monitoring, management point and lack of a clear defense line. In this paper, we report our progress in developing intrusion detection (ID) capabilities for MANET. In our proposed scheme, the network with distributed hierarchical architecture is partitioned into zones, so that in each of them there is one zone manager. The zone manager is responsible for monitoring the cluster heads in its zone and cluster heads are in charge of monitoring their members. However, the most important problem is how the trustworthiness of the zone manager can be recognized. So, we propose a scheme in which "honest neighbors" of zone manager specify the validation of their zone manager. These honest neighbors prevent false accusations and also allow manager if it is wrongly misbehaving. However, if the manger repeats its misbehavior, then it will lose its management degree. Therefore, our scheme will be improved intrusion detection and also provide a more reliable network.

  20. Energy efficiency through integrated environmental management.

    PubMed

    Benromdhane, Souad Ahmed

    2015-05-01

    Integrated environmental management became an economic necessity after industrial development proved to be unsustainable without consideration of environmental direct and indirect impacts. Energy dependency and air pollution along with climate change grew into major challenges facing developed and developing countries alike. Thus, a new global market structure emerged and changed the way we do trade. The search intensified for alternatives to petroleum. However, scientists, policy makers, and environmental activists agreed to focus on strategic conservation and optimization of energy use. Environmental concerns will remain partially unaddressed with the current pace of consumption because greenhouse gas emissions will continue to rise with economic growth. This paper discusses energy efficiency, steady integration of alternative sources, and increased use of best available technologies. Energy criteria developed for environmental labeling certification are presented. Our intention is to encourage manufacturers and service providers to supply consumers with less polluting and energy-consuming goods and services, inform consumers of the environmental and energy impacts, and thereby instill sustainable and responsible consumption. As several programs were initiated in developed countries, environmental labeling requirements created barriers to many exports manufactured in developing countries, affecting current world trade and putting more pressure on countries to meet those requirements. Defining an institutional and legal framework of environmental labeling is a key challenge in implementing such programs for critical economic sectors like tourism, textiles, and food production where energy needs are the most important aspect to control. A case study of Tunisia and its experience with eco-labeling is presented.

  1. A comparison of temperature and precipitation responses to different Earth radiation management geoengineering schemes

    NASA Astrophysics Data System (ADS)

    Crook, J. A.; Jackson, L. S.; Osprey, S. M.; Forster, P. M.

    2015-09-01

    Earth radiation management has been suggested as a way to rapidly counteract global warming in the face of a lack of mitigation efforts, buying time and avoiding potentially catastrophic warming. We compare six different radiation management schemes that use surface, troposphere, and stratosphere interventions in a single climate model in which we projected future climate from 2020 to 2099 based on RCP4.5. We analyze the surface air temperature responses to determine how effective the schemes are at returning temperature to its 1986-2005 climatology and analyze precipitation responses to compare side effects. We find crop albedo enhancement is largely ineffective at returning temperature to its 1986-2005 climatology. Desert albedo enhancement causes excessive cooling in the deserts and severe shifts in tropical precipitation. Ocean albedo enhancement, sea-spray geoengineering, cirrus cloud thinning, and stratospheric SO2 injection have the potential to cool more uniformly, but cirrus cloud thinning may not be able to cool by much more than 1 K globally. We find that of the schemes potentially able to return surface air temperature to 1986-2005 climatology under future greenhouse gas warming, none has significantly less severe precipitation side effects than other schemes. Despite different forcing patterns, ocean albedo enhancement, sea-spray geoengineering, cirrus cloud thinning, and stratospheric SO2 injection all result in large scale tropical precipitation responses caused by Hadley cell changes and land precipitation changes largely driven by thermodynamic changes. Widespread regional scale changes in precipitation over land are significantly different from the 1986-2005 climatology and would likely necessitate significant adaptation despite geoengineering.

  2. Parallel implementation of 3D FFT with volumetric decomposition schemes for efficient molecular dynamics simulations

    NASA Astrophysics Data System (ADS)

    Jung, Jaewoon; Kobayashi, Chigusa; Imamura, Toshiyuki; Sugita, Yuji

    2016-03-01

    Three-dimensional Fast Fourier Transform (3D FFT) plays an important role in a wide variety of computer simulations and data analyses, including molecular dynamics (MD) simulations. In this study, we develop hybrid (MPI+OpenMP) parallelization schemes of 3D FFT based on two new volumetric decompositions, mainly for the particle mesh Ewald (PME) calculation in MD simulations. In one scheme, (1d_Alltoall), five all-to-all communications in one dimension are carried out, and in the other, (2d_Alltoall), one two-dimensional all-to-all communication is combined with two all-to-all communications in one dimension. 2d_Alltoall is similar to the conventional volumetric decomposition scheme. We performed benchmark tests of 3D FFT for the systems with different grid sizes using a large number of processors on the K computer in RIKEN AICS. The two schemes show comparable performances, and are better than existing 3D FFTs. The performances of 1d_Alltoall and 2d_Alltoall depend on the supercomputer network system and number of processors in each dimension. There is enough leeway for users to optimize performance for their conditions. In the PME method, short-range real-space interactions as well as long-range reciprocal-space interactions are calculated. Our volumetric decomposition schemes are particularly useful when used in conjunction with the recently developed midpoint cell method for short-range interactions, due to the same decompositions of real and reciprocal spaces. The 1d_Alltoall scheme of 3D FFT takes 4.7 ms to simulate one MD cycle for a virus system containing more than 1 million atoms using 32,768 cores on the K computer.

  3. On the influence of the partitioning schemes on the efficiency of overlapping domain decomposition methods

    SciTech Connect

    Ciarlet, P. Jr.; Lamour, F.; Smith, B.F.

    1995-06-01

    One level overlapping Schwarz domain decomposition preconditioners can be viewed as a generalization of block Jacobi preconditioning. The effect of the number of blocks and the amount of overlapping between blocks on the convergence rate is well understood. This paper considers the related issue of the effect of the scheme used to partition the matrix into blocks on the convergence rate of the preconditioned iterative method. Numerical results for Laplace and linear elasticity problems in two and three dimensions are presented. The tentative conclusion is that using overlap tends to decrease the differences between the rates of convergence for different partitioning schemes.

  4. Adaptive control schemes for improving dynamic performance of efficiency-optimized induction motor drives.

    PubMed

    Kumar, Navneet; Raj Chelliah, Thanga; Srivastava, S P

    2015-07-01

    Model Based Control (MBC) is one of the energy optimal controllers used in vector-controlled Induction Motor (IM) for controlling the excitation of motor in accordance with torque and speed. MBC offers energy conservation especially at part-load operation, but it creates ripples in torque and speed during load transition, leading to poor dynamic performance of the drive. This study investigates the opportunity for improving dynamic performance of a three-phase IM operating with MBC and proposes three control schemes: (i) MBC with a low pass filter (ii) torque producing current (iqs) injection in the output of speed controller (iii) Variable Structure Speed Controller (VSSC). The pre and post operation of MBC during load transition is also analyzed. The dynamic performance of a 1-hp, three-phase squirrel-cage IM with mine-hoist load diagram is tested. Test results are provided for the conventional field-oriented (constant flux) control and MBC (adjustable excitation) with proposed schemes. The effectiveness of proposed schemes is also illustrated for parametric variations. The test results and subsequent analysis confer that the motor dynamics improves significantly with all three proposed schemes in terms of overshoot/undershoot peak amplitude of torque and DC link power in addition to energy saving during load transitions. PMID:25820090

  5. Efficient conservative ADER schemes based on WENO reconstruction and space-time predictor in primitive variables

    NASA Astrophysics Data System (ADS)

    Zanotti, Olindo; Dumbser, Michael

    2016-01-01

    We present a new version of conservative ADER-WENO finite volume schemes, in which both the high order spatial reconstruction as well as the time evolution of the reconstruction polynomials in the local space-time predictor stage are performed in primitive variables, rather than in conserved ones. To obtain a conservative method, the underlying finite volume scheme is still written in terms of the cell averages of the conserved quantities. Therefore, our new approach performs the spatial WENO reconstruction twice: the first WENO reconstruction is carried out on the known cell averages of the conservative variables. The WENO polynomials are then used at the cell centers to compute point values of the conserved variables, which are subsequently converted into point values of the primitive variables. This is the only place where the conversion from conservative to primitive variables is needed in the new scheme. Then, a second WENO reconstruction is performed on the point values of the primitive variables to obtain piecewise high order reconstruction polynomials of the primitive variables. The reconstruction polynomials are subsequently evolved in time with a novel space-time finite element predictor that is directly applied to the governing PDE written in primitive form. The resulting space-time polynomials of the primitive variables can then be directly used as input for the numerical fluxes at the cell boundaries in the underlying conservative finite volume scheme. Hence, the number of necessary conversions from the conserved to the primitive variables is reduced to just one single conversion at each cell center. We have verified the validity of the new approach over a wide range of hyperbolic systems, including the classical Euler equations of gas dynamics, the special relativistic hydrodynamics (RHD) and ideal magnetohydrodynamics (RMHD) equations, as well as the Baer-Nunziato model for compressible two-phase flows. In all cases we have noticed that the new ADER

  6. A biometric signcryption scheme without bilinear pairing

    NASA Astrophysics Data System (ADS)

    Wang, Mingwen; Ren, Zhiyuan; Cai, Jun; Zheng, Wentao

    2013-03-01

    How to apply the entropy in biometrics into the encryption and remote authentication schemes to simplify the management of keys is a hot research area. Utilizing Dodis's fuzzy extractor method and Liu's original signcryption scheme, a biometric identity based signcryption scheme is proposed in this paper. The proposed scheme is more efficient than most of the previous proposed biometric signcryption schemes for that it does not need bilinear pairing computation and modular exponentiation computation which is time consuming largely. The analysis results show that under the CDH and DL hard problem assumption, the proposed scheme has the features of confidentiality and unforgeability simultaneously.

  7. Efficient scheme for hybrid teleportation via entangled coherent states in circuit quantum electrodynamics.

    PubMed

    Joo, Jaewoo; Ginossar, Eran

    2016-01-01

    We propose a deterministic scheme for teleporting an unknown qubit state through continuous-variable entangled states in superconducting circuits. The qubit is a superconducting two-level system and the bipartite quantum channel is a microwave photonic entangled coherent state between two cavities. A Bell-type measurement performed on the hybrid state of solid and photonic states transfers a discrete-variable unknown electronic state to a continuous-variable photonic cat state in a cavity mode. In order to facilitate the implementation of such complex protocols we propose a design for reducing the self-Kerr nonlinearity in the cavity. The teleporation scheme enables quantum information processing operations with circuit-QED based on entangled coherent states. These include state verification and single-qubit operations with entangled coherent states. These are shown to be experimentally feasible with the state of the art superconducting circuits. PMID:27245775

  8. Efficient scheme for hybrid teleportation via entangled coherent states in circuit quantum electrodynamics

    PubMed Central

    Joo, Jaewoo; Ginossar, Eran

    2016-01-01

    We propose a deterministic scheme for teleporting an unknown qubit state through continuous-variable entangled states in superconducting circuits. The qubit is a superconducting two-level system and the bipartite quantum channel is a microwave photonic entangled coherent state between two cavities. A Bell-type measurement performed on the hybrid state of solid and photonic states transfers a discrete-variable unknown electronic state to a continuous-variable photonic cat state in a cavity mode. In order to facilitate the implementation of such complex protocols we propose a design for reducing the self-Kerr nonlinearity in the cavity. The teleporation scheme enables quantum information processing operations with circuit-QED based on entangled coherent states. These include state verification and single-qubit operations with entangled coherent states. These are shown to be experimentally feasible with the state of the art superconducting circuits. PMID:27245775

  9. Efficient scheme for hybrid teleportation via entangled coherent states in circuit quantum electrodynamics.

    PubMed

    Joo, Jaewoo; Ginossar, Eran

    2016-06-01

    We propose a deterministic scheme for teleporting an unknown qubit state through continuous-variable entangled states in superconducting circuits. The qubit is a superconducting two-level system and the bipartite quantum channel is a microwave photonic entangled coherent state between two cavities. A Bell-type measurement performed on the hybrid state of solid and photonic states transfers a discrete-variable unknown electronic state to a continuous-variable photonic cat state in a cavity mode. In order to facilitate the implementation of such complex protocols we propose a design for reducing the self-Kerr nonlinearity in the cavity. The teleporation scheme enables quantum information processing operations with circuit-QED based on entangled coherent states. These include state verification and single-qubit operations with entangled coherent states. These are shown to be experimentally feasible with the state of the art superconducting circuits.

  10. Efficient scheme for hybrid teleportation via entangled coherent states in circuit quantum electrodynamics

    NASA Astrophysics Data System (ADS)

    Joo, Jaewoo; Ginossar, Eran

    2016-06-01

    We propose a deterministic scheme for teleporting an unknown qubit state through continuous-variable entangled states in superconducting circuits. The qubit is a superconducting two-level system and the bipartite quantum channel is a microwave photonic entangled coherent state between two cavities. A Bell-type measurement performed on the hybrid state of solid and photonic states transfers a discrete-variable unknown electronic state to a continuous-variable photonic cat state in a cavity mode. In order to facilitate the implementation of such complex protocols we propose a design for reducing the self-Kerr nonlinearity in the cavity. The teleporation scheme enables quantum information processing operations with circuit-QED based on entangled coherent states. These include state verification and single-qubit operations with entangled coherent states. These are shown to be experimentally feasible with the state of the art superconducting circuits.

  11. Maximizing Thermal Efficiency and Optimizing Energy Management (Fact Sheet)

    SciTech Connect

    Not Available

    2012-03-01

    Researchers at the Thermal Test Facility (TTF) on the campus of the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) in Golden, Colorado, are addressing maximizing thermal efficiency and optimizing energy management through analysis of efficient heating, ventilating, and air conditioning (HVAC) strategies, automated home energy management (AHEM), and energy storage systems.

  12. 24 CFR 1006.325 - Maintenance, management and efficient operation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... § 1006.325 Maintenance, management and efficient operation. (a) Written policies. The DHHL must develop... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Maintenance, management and efficient operation. 1006.325 Section 1006.325 Housing and Urban Development Regulations Relating to...

  13. An Energy-Efficient Transmission Scheme for Real-Time Data in Wireless Sensor Networks

    PubMed Central

    Kim, Jin-Woo; Barrado, José Ramón Ramos; Jeon, Dong-Keun

    2015-01-01

    The Internet of things (IoT) is a novel paradigm where all things or objects in daily life can communicate with other devices and provide services over the Internet. Things or objects need identifying, sensing, networking and processing capabilities to make the IoT paradigm a reality. The IEEE 802.15.4 standard is one of the main communication protocols proposed for the IoT. The IEEE 802.15.4 standard provides the guaranteed time slot (GTS) mechanism that supports the quality of service (QoS) for the real-time data transmission. In spite of some QoS features in IEEE 802.15.4 standard, the problem of end-to-end delay still remains. In order to solve this problem, we propose a cooperative medium access scheme (MAC) protocol for real-time data transmission. We also evaluate the performance of the proposed scheme through simulation. The simulation results demonstrate that the proposed scheme can improve the network performance. PMID:26007722

  14. Maximum likelihood algorithm using an efficient scheme for computing sensitivities and parameter confidence intervals

    NASA Technical Reports Server (NTRS)

    Murphy, P. C.; Klein, V.

    1984-01-01

    Improved techniques for estimating airplane stability and control derivatives and their standard errors are presented. A maximum likelihood estimation algorithm is developed which relies on an optimization scheme referred to as a modified Newton-Raphson scheme with estimated sensitivities (MNRES). MNRES determines sensitivities by using slope information from local surface approximations of each output variable in parameter space. The fitted surface allows sensitivity information to be updated at each iteration with a significant reduction in computational effort compared to integrating the analytically-determined sensitivity equations or using a finite difference scheme. An aircraft estimation problem is solved using real flight data to compare MNRES with the commonly used modified Newton-Raphson technique; MNRES is found to be faster and more generally applicable. Parameter standard errors are determined using a random search technique. The confidence intervals obtained are compared with Cramer-Rao lower bounds at the same confidence level. It is observed that the nonlinearity of the cost function is an important factor in the relationship between Cramer-Rao bounds and the error bounds determined by the search technique.

  15. An energy-efficient transmission scheme for real-time data in wireless sensor networks.

    PubMed

    Kim, Jin-Woo; Barrado, José Ramón Ramos; Jeon, Dong-Keun

    2015-05-20

    The Internet of things (IoT) is a novel paradigm where all things or objects in daily life can communicate with other devices and provide services over the Internet. Things or objects need identifying, sensing, networking and processing capabilities to make the IoT paradigm a reality. The IEEE 802.15.4 standard is one of the main communication protocols proposed for the IoT. The IEEE 802.15.4 standard provides the guaranteed time slot (GTS) mechanism that supports the quality of service (QoS) for the real-time data transmission. In spite of some QoS features in IEEE 802.15.4 standard, the problem of end-to-end delay still remains. In order to solve this problem, we propose a cooperative medium access scheme (MAC) protocol for real-time data transmission. We also evaluate the performance of the proposed scheme through simulation. The simulation results demonstrate that the proposed scheme can improve the network performance.

  16. Efficient numerical schemes for viscoplastic avalanches. Part 1: The 1D case

    SciTech Connect

    Fernández-Nieto, Enrique D.

    2014-05-01

    This paper deals with the numerical resolution of a shallow water viscoplastic flow model. Viscoplastic materials are characterized by the existence of a yield stress: below a certain critical threshold in the imposed stress, there is no deformation and the material behaves like a rigid solid, but when that yield value is exceeded, the material flows like a fluid. In the context of avalanches, it means that after going down a slope, the material can stop and its free surface has a non-trivial shape, as opposed to the case of water (Newtonian fluid). The model involves variational inequalities associated with the yield threshold: finite-volume schemes are used together with duality methods (namely Augmented Lagrangian and Bermúdez–Moreno) to discretize the problem. To be able to accurately simulate the stopping behavior of the avalanche, new schemes need to be designed, involving the classical notion of well-balancing. In the present context, it needs to be extended to take into account the viscoplastic nature of the material as well as general bottoms with wet/dry fronts which are encountered in geophysical geometries. We derived such schemes and numerical experiments are presented to show their performances.

  17. Efficient Schemes for Reducing Numerical Dispersion in ModelingMultiphase Transport through Porous and Fractured Media

    SciTech Connect

    Wu, Yu-Shu; Forsyth, Peter A.

    2006-04-13

    Numerical issues with modeling transport of chemicals or solute in realistic large-scale subsurface systems have been a serious concern, even with the continual progress made in both simulation algorithms and computer hardware in the past few decades. The problem remains and becomes even more difficult when dealing with chemical transport in a multiphase flow system using coarse, multidimensional regular or irregular grids, because of the known effects of numerical dispersion associated with moving plume fronts. We have investigated several total-variation-diminishing (TVD) or flux-limiter schemes by implementing and testing them in the T2R3D code, one of the TOUGH2 family of codes. The objectives of this paper are (1) to investigate the possibility of applying these TVD schemes, using multi-dimensional irregular unstructured grids, and (2) to help select more accurate spatial averaging methods for simulating chemical transport given a numerical grid or spatial discretization. We present an application example to show that such TVD schemes are able to effectively reduce numerical dispersion.

  18. Comparison of Aircraft Models and Integration Schemes for Interval Management in the TRACON

    NASA Technical Reports Server (NTRS)

    Neogi, Natasha; Hagen, George E.; Herencia-Zapana, Heber

    2012-01-01

    Reusable models of common elements for communication, computation, decision and control in air traffic management are necessary in order to enable simulation, analysis and assurance of emergent properties, such as safety and stability, for a given operational concept. Uncertainties due to faults, such as dropped messages, along with non-linearities and sensor noise are an integral part of these models, and impact emergent system behavior. Flight control algorithms designed using a linearized version of the flight mechanics will exhibit error due to model uncertainty, and may not be stable outside a neighborhood of the given point of linearization. Moreover, the communication mechanism by which the sensed state of an aircraft is fed back to a flight control system (such as an ADS-B message) impacts the overall system behavior; both due to sensor noise as well as dropped messages (vacant samples). Additionally simulation of the flight controller system can exhibit further numerical instability, due to selection of the integration scheme and approximations made in the flight dynamics. We examine the theoretical and numerical stability of a speed controller under the Euler and Runge-Kutta schemes of integration, for the Maintain phase for a Mid-Term (2035-2045) Interval Management (IM) Operational Concept for descent and landing operations. We model uncertainties in communication due to missed ADS-B messages by vacant samples in the integration schemes, and compare the emergent behavior of the system, in terms of stability, via the boundedness of the final system state. Any bound on the errors incurred by these uncertainties will play an essential part in a composable assurance argument required for real-time, flight-deck guidance and control systems,. Thus, we believe that the creation of reusable models, which possess property guarantees, such as safety and stability, is an innovative and essential requirement to assessing the emergent properties of novel airspace

  19. Efficient Evaluation System for Learning Management Systems

    ERIC Educational Resources Information Center

    Cavus, Nadire

    2009-01-01

    A learning management system (LMS) provides the platform for web-based learning environment by enabling the management, delivery, tracking of learning, testing, communication, registration process and scheduling. There are many LMS systems on the market that can be obtained for free or through payment. It has now become an important task to choose…

  20. Survivable wavelength-division multiplexing passive optical network system with centralized protection routing scheme and efficient wavelength utilization

    NASA Astrophysics Data System (ADS)

    Zhou, Zhao; Xiao, Shilin; Bi, Meihua; Qi, Tao; Li, Pingqing; Hu, Weisheng

    2013-09-01

    A survivable wavelength-division multiplexing passive optical network (WDM-PON) with centralized protection scheme and colorless optical network units is proposed. The sideband channels generated via optical carrier suppression technique are used to carry both the downstream (DS) and the upstream (US) remodulated signals for two neighboring sub-PONs. By employing alternate path routing of sideband channels, the centralized protection scheme can provide reliable protection against any failure in feed fibers, remote node, and distribution fibers. The number of extra fibers is greatly reduced, and efficient utilization of wavelength resource is achieved. The feasibility of the proposed system is verified by 10-Gb/s DS and 1.25-Gb/s US signals over 25-km single-mode fiber transmission in both working and protection modes.

  1. Online fault adaptive control for efficient resource management in Advanced Life Support Systems

    NASA Technical Reports Server (NTRS)

    Abdelwahed, Sherif; Wu, Jian; Biswas, Gautam; Ramirez, John; Manders, Eric-J

    2005-01-01

    This article presents the design and implementation of a controller scheme for efficient resource management in Advanced Life Support Systems. In the proposed approach, a switching hybrid system model is used to represent the dynamics of the system components and their interactions. The operational specifications for the controller are represented by utility functions, and the corresponding resource management problem is formulated as a safety control problem. The controller is designed as a limited-horizon online supervisory controller that performs a limited forward search on the state-space of the system at each time step, and uses the utility functions to decide on the best action. The feasibility and accuracy of the online algorithm can be assessed at design time. We demonstrate the effectiveness of the scheme by running a set of experiments on the Reverse Osmosis (RO) subsystem of the Water Recovery System (WRS).

  2. Designing Pay-As-You-Throw schemes in municipal waste management services: A holistic approach.

    PubMed

    Elia, Valerio; Gnoni, Maria Grazia; Tornese, Fabiana

    2015-10-01

    Pay-As-You-Throw (PAYT) strategies are becoming widely applied in solid waste management systems; the main purpose is to support a more sustainable - from economic, environmental and social points of view - management of waste flows. Adopting PAYT charging models increases the complexity level of the waste management service as new organizational issues have to be evaluated compared to flat charging models. In addition, innovative technological solutions could also be adopted to increase the overall efficiency of the service. Unit pricing, user identification and waste measurement represent the three most important processes to be defined in a PAYT system. The paper proposes a holistic framework to support an effective design and management process. The framework defines most critical processes and effective organizational and technological solutions for supporting waste managers as well as researchers. PMID:26235447

  3. Study on the energy-efficient scheme based on the interconnection of optical-network-units for next generation optical access network

    NASA Astrophysics Data System (ADS)

    Lv, Yunxin; Jiang, Ning; Qiu, Kun; Xue, Chenpeng

    2014-12-01

    An energy-efficient scheme based on the interconnection of optical network unit (ONU) is introduced, which can significantly reduce the energy consumption of the low-traffic operation. The energy consumption model for the ONU-interconnected optical access network (OAN) based on the electronic switch (ES) technology is established, and the energy efficiency of the proposed scheme is analyzed and compared with that of the OAN using optical switch (OS). The simulation results demonstrate that the ONU-interconnected scheme can efficiently reduce the energy consumption of OAN, and it shows a good energy consumption performance under daily traffic model.

  4. Hybrid ARQ Error-Controlling Scheme for Robust and Efficient Transmission of UWB Body Area Networks

    NASA Astrophysics Data System (ADS)

    Suzuki, Haruka; Hernandez, Marco; Kohno, Ryuji

    This paper presents hybrid type-II automatic repeat request (H-ARQ) for wireless wearable body area networks (BANs) based on ultra wideband (UWB) technology. The proposed model is based on three schemes, namely, high rate optimized rate compatible punctured convolutional codes (HRO-RCPC), Reed Solomon (RS) invertible codes and their concatenation. Forward error correction (FEC) coding is combined with simple cyclic redundancy check (CRC) error detection. The performance is investigated for two channels: CM3 (on-body to on-body) and CM4 (on-body to a gateway) scenarios of the IEEE802.15.6 BAN channel models for BANs. It is shown that the improvement in performance in terms of throughput and error protection robustness is very significant. Thus, the proposed H-ARQ schemes can be employed and optimized to suit medical and non-medical applications. In particular we propose the use of FEC coding for non-medical applications as those require less stringent quality of service (QoS), while the incremental redundancy and ARQ configuration is utilized only for medical applications. Thus, higher QoS is guaranteed for medical application of BANs while allowing coexistence with non-medical applications.

  5. The Newmark scheme as velocity-stress time-staggering: an efficient PML implementation for spectral element simulations of elastodynamics

    NASA Astrophysics Data System (ADS)

    Festa, Gaetano; Vilotte, Jean-Pierre

    2005-06-01

    Perfectly matched layers (PMLs) provide an exponential decay, independent of the frequency, of any propagating field along an assigned direction without producing spurious reflections at the interface with the elastic volume. For this reason PMLs have been applied as absorbing boundary conditions (ABCs) and their efficiency in attenuating outgoing wave fields on the outskirts of numerical grids is more and more recognized. However, PMLs are designed for first-order differential equations and a natural extension to second-order Partial Differential Equations (PDEs) involves either additional variables in the time evolution scheme or convolutional operations. Both techniques are computationally expensive when implemented in a spectral element (SE) code and other ABCs (e.g. paraxial or standard sponge methods) still remain more attractive than PMLs. Here, an efficient second-order implementation of PMLs for SE is developed from interpreting the Newmark scheme as a time-staggered velocity-stress algorithm. The discrete equivalence with the standard scheme is based on an L2 approximation of the stress field, with the same polynomial order as the velocity. In this case, PMLs can be introduced as for first-order equations preserving the natural second-order time stepping. Subsequently, a non-classical frequency-dependent perfectly matched layer is introduced by moving the pole of the stretching along the imaginary axis. In this case, the absorption depends on the frequency and the layer switches from a transparent behaviour at low frequencies to a uniform absorption as the frequency goes to infinity. It turns out to be more efficient than classical PMLs in the absorption of the incident waves, as the grazing incidence approaches, at the cost of a memory variable for any split component. Finally, an extension of PMLs to general curvilinear coordinates is proposed.

  6. A Hybrid Key Management Scheme for WSNs Based on PPBR and a Tree-Based Path Key Establishment Method.

    PubMed

    Zhang, Ying; Liang, Jixing; Zheng, Bingxin; Chen, Wei

    2016-01-01

    With the development of wireless sensor networks (WSNs), in most application scenarios traditional WSNs with static sink nodes will be gradually replaced by Mobile Sinks (MSs), and the corresponding application requires a secure communication environment. Current key management researches pay less attention to the security of sensor networks with MS. This paper proposes a hybrid key management schemes based on a Polynomial Pool-based key pre-distribution and Basic Random key pre-distribution (PPBR) to be used in WSNs with MS. The scheme takes full advantages of these two kinds of methods to improve the cracking difficulty of the key system. The storage effectiveness and the network resilience can be significantly enhanced as well. The tree-based path key establishment method is introduced to effectively solve the problem of communication link connectivity. Simulation clearly shows that the proposed scheme performs better in terms of network resilience, connectivity and storage effectiveness compared to other widely used schemes. PMID:27070624

  7. A Hybrid Key Management Scheme for WSNs Based on PPBR and a Tree-Based Path Key Establishment Method.

    PubMed

    Zhang, Ying; Liang, Jixing; Zheng, Bingxin; Chen, Wei

    2016-04-09

    With the development of wireless sensor networks (WSNs), in most application scenarios traditional WSNs with static sink nodes will be gradually replaced by Mobile Sinks (MSs), and the corresponding application requires a secure communication environment. Current key management researches pay less attention to the security of sensor networks with MS. This paper proposes a hybrid key management schemes based on a Polynomial Pool-based key pre-distribution and Basic Random key pre-distribution (PPBR) to be used in WSNs with MS. The scheme takes full advantages of these two kinds of methods to improve the cracking difficulty of the key system. The storage effectiveness and the network resilience can be significantly enhanced as well. The tree-based path key establishment method is introduced to effectively solve the problem of communication link connectivity. Simulation clearly shows that the proposed scheme performs better in terms of network resilience, connectivity and storage effectiveness compared to other widely used schemes.

  8. A Hybrid Key Management Scheme for WSNs Based on PPBR and a Tree-Based Path Key Establishment Method

    PubMed Central

    Zhang, Ying; Liang, Jixing; Zheng, Bingxin; Chen, Wei

    2016-01-01

    With the development of wireless sensor networks (WSNs), in most application scenarios traditional WSNs with static sink nodes will be gradually replaced by Mobile Sinks (MSs), and the corresponding application requires a secure communication environment. Current key management researches pay less attention to the security of sensor networks with MS. This paper proposes a hybrid key management schemes based on a Polynomial Pool-based key pre-distribution and Basic Random key pre-distribution (PPBR) to be used in WSNs with MS. The scheme takes full advantages of these two kinds of methods to improve the cracking difficulty of the key system. The storage effectiveness and the network resilience can be significantly enhanced as well. The tree-based path key establishment method is introduced to effectively solve the problem of communication link connectivity. Simulation clearly shows that the proposed scheme performs better in terms of network resilience, connectivity and storage effectiveness compared to other widely used schemes. PMID:27070624

  9. A novel power-efficient scheme asymmetrically and symmetrically clipping optical (ASCO)-OFDM for IM/DD optical systems

    NASA Astrophysics Data System (ADS)

    Wu, Nan; Bar-Ness, Yeheskel

    2015-12-01

    In this paper, we propose a novel scheme of orthogonal frequency division multiplexing (OFDM) for intensity modulation direct detection (IM/DD) optical systems. By using this novel scheme of an OFDM optical system, not only odd subcarriers but also even subcarriers can be modulated to transmit a clipping optical signal. A conventional asymmetrically clipping optical (ACO)-OFDM is applied to modulate odd subcarriers while even subcarriers are modulated by a novel technique called a symmetrically clipping optical (SCO)-OFDM. Although both the asymmetrically clipping noise caused by ACO-OFDM and the symmetrically clipping noise caused by SCO-OFDM fall onto the even subcarriers, the former interference can be estimated and removed at the receiver. Thus, SCO-OFDM symbols carried on the even subcarriers can be recovered by subtracting the estimated ACO-OFDM clipping noise from the received signal. Then the SCO-OFDM clipping noise can be removed by subtraction due to its special transmission format. Note that no DC bias added on all subcarriers makes this novel scheme achieve better performance in terms of both power efficiency and symbol error rate (SER).

  10. CCS_WHMS: A Congestion Control Scheme for Wearable Health Management System.

    PubMed

    Kafi, Mohamed Amine; Ben Othman, Jalel; Bagaa, Miloud; Badache, Nadjib

    2015-12-01

    Wearable computing is becoming a more and more attracting field in the last years thanks to the miniaturisation of electronic devices. Wearable healthcare monitoring systems (WHMS) as an important client of wearable computing technology has gained a lot. Indeed, the wearable sensors and their surrounding healthcare applications bring a lot of benefits to patients, elderly people and medical staff, so facilitating their daily life quality. But from a research point of view, there is still work to accomplish in order to overcome the gap between hardware and software parts. In this paper, we target the problem of congestion control when all these healthcare sensed data have to reach the destination in a reliable manner that avoids repetitive transmission which wastes precious energy or leads to loss of important information in emergency cases, too. We propose a congestion control scheme CCS_WHMS that ensures efficient and fair data delivery while used in the body wearable system part or in the multi-hop inter bodies wearable ones to get the destination. As the congestion detection paradigm is very important in the control process, we do experimental tests to compare between state of the art congestion detection methods, using MICAz motes, in order to choose the appropriate one for our scheme.

  11. Spin-torque resonant expulsion of the vortex core for an efficient radiofrequency detection scheme

    NASA Astrophysics Data System (ADS)

    Jenkins, A. S.; Lebrun, R.; Grimaldi, E.; Tsunegi, S.; Bortolotti, P.; Kubota, H.; Yakushiji, K.; Fukushima, A.; de Loubens, G.; Klein, O.; Yuasa, S.; Cros, V.

    2016-04-01

    It has been proposed that high-frequency detectors based on the so-called spin-torque diode effect in spin transfer oscillators could eventually replace conventional Schottky diodes due to their nanoscale size, frequency tunability and large output sensitivity. Although a promising candidate for information and communications technology applications, the output voltage generated from this effect has still to be improved and, more pertinently, reduces drastically with decreasing radiofrequency (RF) current. Here we present a scheme for a new type of spintronics-based high-frequency detector based on the expulsion of the vortex core in a magnetic tunnel junction (MTJ). The resonant expulsion of the core leads to a large and sharp change in resistance associated with the difference in magnetoresistance between the vortex ground state and the final C-state configuration. Interestingly, this reversible effect is independent of the incoming RF current amplitude, offering a fast real-time RF threshold detector.

  12. D-MSR: A Distributed Network Management Scheme for Real-Time Monitoring and Process Control Applications in Wireless Industrial Automation

    PubMed Central

    Zand, Pouria; Dilo, Arta; Havinga, Paul

    2013-01-01

    Current wireless technologies for industrial applications, such as WirelessHART and ISA100.11a, use a centralized management approach where a central network manager handles the requirements of the static network. However, such a centralized approach has several drawbacks. For example, it cannot cope with dynamicity/disturbance in large-scale networks in a real-time manner and it incurs a high communication overhead and latency for exchanging management traffic. In this paper, we therefore propose a distributed network management scheme, D-MSR. It enables the network devices to join the network, schedule their communications, establish end-to-end connections by reserving the communication resources for addressing real-time requirements, and cope with network dynamicity (e.g., node/edge failures) in a distributed manner. According to our knowledge, this is the first distributed management scheme based on IEEE 802.15.4e standard, which guides the nodes in different phases from joining until publishing their sensor data in the network. We demonstrate via simulation that D-MSR can address real-time and reliable communication as well as the high throughput requirements of industrial automation wireless networks, while also achieving higher efficiency in network management than WirelessHART, in terms of delay and overhead. PMID:23807687

  13. D-MSR: a distributed network management scheme for real-time monitoring and process control applications in wireless industrial automation.

    PubMed

    Zand, Pouria; Dilo, Arta; Havinga, Paul

    2013-01-01

    Current wireless technologies for industrial applications, such as WirelessHART and ISA100.11a, use a centralized management approach where a central network manager handles the requirements of the static network. However, such a centralized approach has several drawbacks. For example, it cannot cope with dynamicity/disturbance in large-scale networks in a real-time manner and it incurs a high communication overhead and latency for exchanging management traffic. In this paper, we therefore propose a distributed network management scheme, D-MSR. It enables the network devices to join the network, schedule their communications, establish end-to-end connections by reserving the communication resources for addressing real-time requirements, and cope with network dynamicity (e.g., node/edge failures) in a distributed manner. According to our knowledge, this is the first distributed management scheme based on IEEE 802.15.4e standard, which guides the nodes in different phases from joining until publishing their sensor data in the network. We demonstrate via simulation that D-MSR can address real-time and reliable communication as well as the high throughput requirements of industrial automation wireless networks, while also achieving higher efficiency in network management than WirelessHART, in terms of delay and overhead.

  14. Management development. The MESOL (Management Education Scheme by Open Learning) experience.

    PubMed

    Wellman, N

    1994-01-01

    Explores and attempts to reconcile some of the differences between traditional professional and academic management qualifications and those based on the NVQ competence model. Based on the experience of Universities and Higher Education institutions delivering open learning MESOL materials to the UK health and social care sector, focuses on the different assessment methodologies used by each. Concludes that it is necessary to differentiate clearly between the traditional input/knowledge-based model and the competence-based approach of the NVQ. This will allow candidates to contextualize and consolidate learning in the workplace prior to revisiting their performance at a later date. PMID:10134589

  15. Efficient High Order Central Schemes for Multi-Dimensional Hamilton-Jacobi Equations: Talk Slides

    NASA Technical Reports Server (NTRS)

    Bryson, Steve; Levy, Doron; Biegel, Brian R. (Technical Monitor)

    2002-01-01

    This viewgraph presentation presents information on the attempt to produce high-order, efficient, central methods that scale well to high dimension. The central philosophy is that the equations should evolve to the point where the data is smooth. This is accomplished by a cyclic pattern of reconstruction, evolution, and re-projection. One dimensional and two dimensional representational methods are detailed, as well.

  16. Progress Towards Optimally Efficient Schemes for Monte Carlo Thermal Radiation Transport

    SciTech Connect

    Smedley-Stevenson, R P; Brooks III, E D

    2007-09-26

    In this summary we review the complementary research being undertaken at AWE and LLNL aimed at developing optimally efficient algorithms for Monte Carlo thermal radiation transport based on the difference formulation. We conclude by presenting preliminary results on the application of Newton-Krylov methods for solving the Symbolic Implicit Monte Carlo (SIMC) energy equation.

  17. Efficient checkpointing schemes for depletion perturbation solutions on memory-limited architectures

    SciTech Connect

    Stripling, H. F.; Adams, M. L.; Hawkins, W. D.

    2013-07-01

    We describe a methodology for decreasing the memory footprint and machine I/O load associated with the need to access a forward solution during an adjoint solve. Specifically, we are interested in the depletion perturbation equations, where terms in the adjoint Bateman and transport equations depend on the forward flux solution. Checkpointing is the procedure of storing snapshots of the forward solution to disk and using these snapshots to recompute the parts of the forward solution that are necessary for the adjoint solve. For large problems, however, the storage cost of just a few copies of an angular flux vector can exceed the available RAM on the host machine. We propose a methodology that does not checkpoint the angular flux vector; instead, we write and store converged source moments, which are typically of a much lower dimension than the angular flux solution. This reduces the memory footprint and I/O load of the problem, but requires that we perform single sweeps to reconstruct flux vectors on demand. We argue that this trade-off is exactly the kind of algorithm that will scale on advanced, memory-limited architectures. We analyze the cost, in terms of FLOPS and memory footprint, of five checkpointing schemes. We also provide computational results that support the analysis and show that the memory-for-work trade off does improve time to solution. (authors)

  18. Fuzzy logic to improve efficiency of finite element and finite difference schemes

    SciTech Connect

    Garcia, M.D.; Heger, A.S.

    1994-05-01

    This paper explores possible applications of logic in the areas of finite element and finite difference methods applied to engineering design problems. The application of fuzzy logic to both front-end selection of computational options and within the numerical computation itself are proposed. Further, possible methods of overcoming these limitations through the application of methods are explored. Decision strategy is a fundamental limitation in performing finite element calculations, such as selecting the optimum coarseness of the grid, numerical integration algorithm, element type, implicit versus explicit schemes, and the like. This is particularly true of novice analysts who are confronted with a myriad of choices in performing a calculation. The advantage of having the myriad of options available to the analyst is, however, that it improves and optimizes the design process if the appropriate ones are selected. Unfortunately, the optimum choices are not always apparent and only through the process of elimination or prior extensive experience can the optimum choices or combination of choices be selected. The knowledge of expert analysts could be integrated into a fuzzy ``front-end`` rule-based package to optimize the design process. The use of logic to capture the heuristic and human knowledge for selecting optimum solution strategies sets the framework for these proposed strategies.

  19. Spin torque resonant vortex core expulsion for an efficient radio-frequency detection scheme

    NASA Astrophysics Data System (ADS)

    Cros, V.; Jenkins, A. S.; Lebrun, R.; Bortolotti, P.; Grimaldi, E.; Tsunegi, S.; Kubota, H.; Yakushiji, K.; Fukushima, A.; Yuasa, S.

    It has been proposed by Tulaparkur et al.[1ref] that a high frequency detector based on the so called spin-diode effect in spin transfer oscillators could eventually replace conventional Schottky diodes, due to their nanoscale size, frequency tunability, and large output sensitivity. Although a promising candidate for ICT applications, the output voltage generated from this effect is consistently low. Here we present a scheme for a new type of spintronics-based high frequency detector based on the expulsion of the vortex core of a magnetic tunnel junction. The resonant expulsion of the core leads to a large and sharp change in resistance associated with the difference in magnetoresistance between the vortex ground state and the final C-state, which is predominantly in either the parallel or anti-parallel direction relative to the polariser layer. Interestingly, this reversible effect is independent of the incoming rf current amplitude, offering a compelling perspective for a fast real-time rf threshold detector. REF : EU FP7 Grant (MOSAIC No. ICT-FP7-317950 is acknowledged.

  20. Efficient implementation of Batcher's odd-even merge algorithm and its application in parallel sorting schemes

    SciTech Connect

    Kumar, M.; Hirschberg, D.S.

    1983-03-01

    An algorithm is presented to merge two subfiles of size n/2 each, stored in the left and the right halves of a linearly connected processor array, in 3n/2 route steps and log n compare-exchange steps. This algorithm is extended to merge two horizontally adjacent subfiles of size m*n/2 each, stored in an m*n mesh-connected processor array in row-major order, in m+2n route steps and log mn compare-exchange steps. Also an algorithm is presented to merge two vertically aligned subfiles, stored in a mesh-connected processor array in row-major order. Finally, a sorting scheme is proposed that requires 11n route steps and 2 log/sup 2/ n compare-exchange steps to sort n/sup 2/ elements stored in an n*n mesh-connected processor array. The merge algorithms for the mesh-connected processor array use wrap around connections. These connections can be avoided at the expense of some extra hardware. 12 references.

  1. Thermal management concepts for higher efficiency heavy vehicles.

    SciTech Connect

    Wambsganss, M. W.

    1999-05-19

    Thermal management is a cross-cutting technology that directly or indirectly affects engine performance, fuel economy, safety and reliability, aerodynamics, driver/passenger comfort, materials selection, emissions, maintenance, and component life. This review paper provides an assessment of thermal management for large trucks, particularly as it impacts these features. Observations arrived at from a review of the state of the art for thermal management for over-the-road trucks are highlighted and commented on. Trends in the large truck industry, pertinent engine truck design and performance objectives, and the implications of these relative to thermal management, are presented. Finally, new thermal management concepts for high efficiency vehicles are described.

  2. Optimization schemes for efficient multiple exciton generation and extraction in colloidal quantum dots

    NASA Astrophysics Data System (ADS)

    Damtie, Fikeraddis A.; Karki, Khadga J.; Pullerits, Tõnu; Wacker, Andreas

    2016-08-01

    Multiple exciton generation (MEG) is a process in which more than one electron hole pair is generated per absorbed photon. It allows us to increase the efficiency of solar energy harvesting. Experimental studies have shown the multiple exciton generation yield of 1.2 in isolated colloidal quantum dots. However real photoelectric devices require the extraction of electron hole pairs to electric contacts. We provide a systematic study of the corresponding quantum coherent processes including extraction and injection and show that a proper design of extraction and injection rates enhances the yield significantly up to values around 1.6.

  3. Managed care and the scale efficiency of US hospitals.

    PubMed

    Brown, H Shelton; Pagán, José A

    2006-12-01

    Managed care penetration has been partly responsible for slowing down increases in health care costs in recent years. This study uses a 1992-1996 Health Care Utilization Project sample of hospitals to analyze the relationship between managed care penetration in local insurance markets and hospital scale efficiency. After controlling for hospital and market area variables, we find that managed care insurance, particularly the preferred provider type, is associated with increases in hospital scale efficiency in tertiary cases. The results presented here are consistent with the view that managed care can lead to reductions in health cost inflation by controlling the diffusion of technology via improvements in the scale efficiency of hospitals. PMID:17111213

  4. Color Image Watermarking Scheme Based on Efficient Preprocessing and Support Vector Machines

    NASA Astrophysics Data System (ADS)

    Fındık, Oğuz; Bayrak, Mehmet; Babaoğlu, Ismail; Çomak, Emre

    This paper suggests a new block based watermarking technique utilizing preprocessing and support vector machine (PPSVMW) to protect color image's intellectual property rights. Binary test set is employed here to train support vector machine (SVM). Before adding binary data into the original image, blocks have been separated into two parts to train SVM for better accuracy. Watermark's 1 valued bits were randomly added into the first block part and 0 into the second block part. Watermark is embedded by modifying the blue channel pixel value in the middle of each block so that watermarked image could be composed. SVM was trained with set-bits and three other features which are averages of the differences of pixels in three distinct shapes extracted from each block, and hence without the need of original image, it could be extracted. The results of PPSVMW technique proposed in this study were compared with those of the Tsai's technique. Our technique was proved to be more efficient.

  5. An Efficient Time-Stepping Scheme for Ab Initio Molecular Dynamics Simulations

    NASA Astrophysics Data System (ADS)

    Tsuchida, Eiji

    2016-08-01

    In ab initio molecular dynamics simulations of real-world problems, the simple Verlet method is still widely used for integrating the equations of motion, while more efficient algorithms are routinely used in classical molecular dynamics. We show that if the Verlet method is used in conjunction with pre- and postprocessing, the accuracy of the time integration is significantly improved with only a small computational overhead. We also propose several extensions of the algorithm required for use in ab initio molecular dynamics. The validity of the processed Verlet method is demonstrated in several examples including ab initio molecular dynamics simulations of liquid water. The structural properties obtained from the processed Verlet method are found to be sufficiently accurate even for large time steps close to the stability limit. This approach results in a 2× performance gain over the standard Verlet method for a given accuracy. We also show how to generate a canonical ensemble within this approach.

  6. Time-dependent density functional theory scheme for efficient calculations of dynamic (hyper)polarizabilities.

    PubMed

    Andrade, Xavier; Botti, Silvana; Marques, Miguel A L; Rubio, Angel

    2007-05-14

    The authors present an efficient perturbative method to obtain both static and dynamic polarizabilities and hyperpolarizabilities of complex electronic systems. This approach is based on the solution of a frequency-dependent Sternheimer equation, within the formalism of time-dependent density functional theory, and allows the calculation of the response both in resonance and out of resonance. Furthermore, the excellent scaling with the number of atoms opens the way to the investigation of response properties of very large molecular systems. To demonstrate the capabilities of this method, they implemented it in a real-space (basis-set-free) code and applied it to benchmark molecules, namely, CO, H2O, and para-nitroaniline. Their results are in agreement with experimental and previous theoretical studies and fully validate their approach. PMID:17508791

  7. Developing a computationally efficient dynamic multilevel hybrid optimization scheme using multifidelity model interactions.

    SciTech Connect

    Hough, Patricia Diane (Sandia National Laboratories, Livermore, CA); Gray, Genetha Anne (Sandia National Laboratories, Livermore, CA); Castro, Joseph Pete Jr.; Giunta, Anthony Andrew

    2006-01-01

    Many engineering application problems use optimization algorithms in conjunction with numerical simulators to search for solutions. The formulation of relevant objective functions and constraints dictate possible optimization algorithms. Often, a gradient based approach is not possible since objective functions and constraints can be nonlinear, nonconvex, non-differentiable, or even discontinuous and the simulations involved can be computationally expensive. Moreover, computational efficiency and accuracy are desirable and also influence the choice of solution method. With the advent and increasing availability of massively parallel computers, computational speed has increased tremendously. Unfortunately, the numerical and model complexities of many problems still demand significant computational resources. Moreover, in optimization, these expenses can be a limiting factor since obtaining solutions often requires the completion of numerous computationally intensive simulations. Therefore, we propose a multifidelity optimization algorithm (MFO) designed to improve the computational efficiency of an optimization method for a wide range of applications. In developing the MFO algorithm, we take advantage of the interactions between multi fidelity models to develop a dynamic and computational time saving optimization algorithm. First, a direct search method is applied to the high fidelity model over a reduced design space. In conjunction with this search, a specialized oracle is employed to map the design space of this high fidelity model to that of a computationally cheaper low fidelity model using space mapping techniques. Then, in the low fidelity space, an optimum is obtained using gradient or non-gradient based optimization, and it is mapped back to the high fidelity space. In this paper, we describe the theory and implementation details of our MFO algorithm. We also demonstrate our MFO method on some example problems and on two applications: earth penetrators and

  8. A fast and efficient adaptive threshold rate control scheme for remote sensing images.

    PubMed

    Chen, Xiao; Xu, Xiaoqing

    2012-01-01

    The JPEG2000 image compression standard is ideal for processing remote sensing images. However, its algorithm is complex and it requires large amounts of memory, making it difficult to adapt to the limited transmission and storage resources necessary for remote sensing images. In the present study, an improved rate control algorithm for remote sensing images is proposed. The required coded blocks are sorted downward according to their numbers of bit planes prior to entropy coding. An adaptive threshold computed from the combination of the minimum number of bit planes, along with the minimum rate-distortion slope and the compression ratio, is used to truncate passes of each code block during Tier-1 encoding. This routine avoids the encoding of all code passes and improves the coding efficiency. The simulation results show that the computational cost and working buffer memory size of the proposed algorithm reach only 18.13 and 7.81%, respectively, of the same parameters in the postcompression rate distortion algorithm, while the peak signal-to-noise ratio across the images remains almost the same. The proposed algorithm not only greatly reduces the code complexity and buffer requirements but also maintains the image quality.

  9. Improving IC process efficiency with critical materials management

    NASA Astrophysics Data System (ADS)

    Hanson, Kathy L.; Andrews, Robert E.

    2003-06-01

    The management of critical materials in a high technology manufacturing facility is crucial to obtaining consistently high production yield. This is especially true in an industry like semiconductors where the success of the product is so dependent on the integrity of the critical production materials. Bar code systems, the traditional management tools, are voluntary, defeatable, and do not continuously monitor materials when in use. The significant costs associated with mis-management of chemicals can be captured with a customized model resulting in highly favorable ROI"s for the NOWTrak RFID chemical management system. This system transmits reliable chemical data about each individual container and generates information that can be used to increase wafer production efficiency and yield. The future of the RFID system will expand beyond the benefits of chemical management and into dynamic IC process management

  10. The role of agri-environment schemes in conservation and environmental management

    PubMed Central

    Batáry, Péter; Dicks, Lynn V; Kleijn, David; Sutherland, William J

    2015-01-01

    Over half of the European landscape is under agricultural management and has been for millennia. Many species and ecosystems of conservation concern in Europe depend on agricultural management and are showing ongoing declines. Agri-environment schemes (AES) are designed partly to address this. They are a major source of nature conservation funding within the European Union (EU) and the highest conservation expenditure in Europe. We reviewed the structure of current AES across Europe. Since a 2003 review questioned the overall effectiveness of AES for biodiversity, there has been a plethora of case studies and meta-analyses examining their effectiveness. Most syntheses demonstrate general increases in farmland biodiversity in response to AES, with the size of the effect depending on the structure and management of the surrounding landscape. This is important in the light of successive EU enlargement and ongoing reforms of AES. We examined the change in effect size over time by merging the data sets of 3 recent meta-analyses and found that schemes implemented after revision of the EU's agri-environmental programs in 2007 were not more effective than schemes implemented before revision. Furthermore, schemes aimed at areas out of production (such as field margins and hedgerows) are more effective at enhancing species richness than those aimed at productive areas (such as arable crops or grasslands). Outstanding research questions include whether AES enhance ecosystem services, whether they are more effective in agriculturally marginal areas than in intensively farmed areas, whether they are more or less cost-effective for farmland biodiversity than protected areas, and how much their effectiveness is influenced by farmer training and advice? The general lesson from the European experience is that AES can be effective for conserving wildlife on farmland, but they are expensive and need to be carefully designed and targeted. El Papel de los Esquemas Agro-Ambientales en

  11. The role of agri-environment schemes in conservation and environmental management

    PubMed Central

    Batáry, Péter; Dicks, Lynn V; Kleijn, David; Sutherland, William J

    2015-01-01

    Over half of the European landscape is under agricultural management and has been for millennia. Many species and ecosystems of conservation concern in Europe depend on agricultural management and are showing ongoing declines. Agri-environment schemes (AES) are designed partly to address this. They are a major source of nature conservation funding within the European Union (EU) and the highest conservation expenditure in Europe. We reviewed the structure of current AES across Europe. Since a 2003 review questioned the overall effectiveness of AES for biodiversity, there has been a plethora of case studies and meta-analyses examining their effectiveness. Most syntheses demonstrate general increases in farmland biodiversity in response to AES, with the size of the effect depending on the structure and management of the surrounding landscape. This is important in the light of successive EU enlargement and ongoing reforms of AES. We examined the change in effect size over time by merging the data sets of 3 recent meta-analyses and found that schemes implemented after revision of the EU's agri-environmental programs in 2007 were not more effective than schemes implemented before revision. Furthermore, schemes aimed at areas out of production (such as field margins and hedgerows) are more effective at enhancing species richness than those aimed at productive areas (such as arable crops or grasslands). Outstanding research questions include whether AES enhance ecosystem services, whether they are more effective in agriculturally marginal areas than in intensively farmed areas, whether they are more or less cost-effective for farmland biodiversity than protected areas, and how much their effectiveness is influenced by farmer training and advice? The general lesson from the European experience is that AES can be effective for conserving wildlife on farmland, but they are expensive and need to be carefully designed and targeted. El Papel de los Esquemas Agro-Ambientales en

  12. Breeding scheme and maternal small RNAs affect the efficiency of transgenerational inheritance of a paramutation in mice.

    PubMed

    Yuan, Shuiqiao; Oliver, Daniel; Schuster, Andrew; Zheng, Huili; Yan, Wei

    2015-03-18

    Paramutations result from interactions between two alleles at a single locus, whereby one induces a heritable change in the other. Although common in plants, paramutations are rarely studied in animals. Here, we report a new paramutation mouse model, in which the paramutant allele was induced by an insertional mutation and displayed the "white-tail-tip" (WTT) phenotype. The paramutation phenotype could be transmitted across multiple generations, and the breeding scheme (intercrossing vs. outcrossing) drastically affected the transmission efficiency. Paternal (i.e., sperm-borne) RNAs isolated from paramutant mice could induce the paramutation phenotype, which, however, failed to be transmitted to subsequent generations. Maternal miRNAs and piRNAs appeared to have an inhibitory effect on the efficiency of germline transmission of the paramutation. This paramutation mouse model represents an important tool for dissecting the underlying mechanism, which should be applicable to the phenomenon of epigenetic transgenerational inheritance (ETI) in general. Mechanistic insights of ETI will help us understand how organisms establish new heritable epigenetic states during development, or in times of environmental or nutritional stress.

  13. Breeding scheme and maternal small RNAs affect the efficiency of transgenerational inheritance of a paramutation in mice

    PubMed Central

    Yuan, Shuiqiao; Oliver, Daniel; Schuster, Andrew; Zheng, Huili; Yan, Wei

    2015-01-01

    Paramutations result from interactions between two alleles at a single locus, whereby one induces a heritable change in the other. Although common in plants, paramutations are rarely studied in animals. Here, we report a new paramutation mouse model, in which the paramutant allele was induced by an insertional mutation and displayed the “white-tail-tip” (WTT) phenotype. The paramutation phenotype could be transmitted across multiple generations, and the breeding scheme (intercrossing vs. outcrossing) drastically affected the transmission efficiency. Paternal (i.e., sperm-borne) RNAs isolated from paramutant mice could induce the paramutation phenotype, which, however, failed to be transmitted to subsequent generations. Maternal miRNAs and piRNAs appeared to have an inhibitory effect on the efficiency of germline transmission of the paramutation. This paramutation mouse model represents an important tool for dissecting the underlying mechanism, which should be applicable to the phenomenon of epigenetic transgenerational inheritance (ETI) in general. Mechanistic insights of ETI will help us understand how organisms establish new heritable epigenetic states during development, or in times of environmental or nutritional stress. PMID:25783852

  14. Strategies for Energy Efficient Resource Management of Hybrid Programming Models

    SciTech Connect

    Li, Dong; Supinski, Bronis de; Schulz, Martin; Nikolopoulos, Dimitrios S; Cameron, Kirk W.

    2013-01-01

    Many scientific applications are programmed using hybrid programming models that use both message-passing and shared-memory, due to the increasing prevalence of large-scale systems with multicore, multisocket nodes. Previous work has shown that energy efficiency can be improved using software-controlled execution schemes that consider both the programming model and the power-aware execution capabilities of the system. However, such approaches have focused on identifying optimal resource utilization for one programming model, either shared-memory or message-passing, in isolation. The potential solution space, thus the challenge, increases substantially when optimizing hybrid models since the possible resource configurations increase exponentially. Nonetheless, with the accelerating adoption of hybrid programming models, we increasingly need improved energy efficiency in hybrid parallel applications on large-scale systems. In this work, we present new software-controlled execution schemes that consider the effects of dynamic concurrency throttling (DCT) and dynamic voltage and frequency scaling (DVFS) in the context of hybrid programming models. Specifically, we present predictive models and novel algorithms based on statistical analysis that anticipate application power and time requirements under different concurrency and frequency configurations. We apply our models and methods to the NPB MZ benchmarks and selected applications from the ASC Sequoia codes. Overall, we achieve substantial energy savings (8.74% on average and up to 13.8%) with some performance gain (up to 7.5%) or negligible performance loss.

  15. Managing Sustainable Development Conflicts: The Impact of Stakeholders in Small-Scale Hydropower Schemes

    NASA Astrophysics Data System (ADS)

    Watkin, Laura Jane; Kemp, Paul S.; Williams, Ian D.; Harwood, Ian A.

    2012-06-01

    The growing importance of the environment and its management has simultaneously emphasized the benefits of hydroelectric power and its environmental costs. In a changing policy climate, giving importance to renewable energy development and environmental protection, conflict potential between stakeholders is considerable. Navigation of conflict determines the scheme constructed, making sustainable hydropower a function of human choice. To meet the needs of practitioners, greater understanding of stakeholder conflict is needed. This paper presents an approach to illustrate the challenges that face small-scale hydropower development as perceived by the stakeholders involved, and how they influence decision-making. Using Gordleton Mill, Hampshire (UK), as an illustrative case, soft systems methodology, a systems modeling approach, was adopted. Through individual interviews, a range of problems were identified and conceptually modeled. Stakeholder bias towards favoring economic appraisal over intangible social and environmental aspects was identified; costs appeared more influential than profit. Conceptual evaluation of the requirements to meet a stakeholder-approved solution suggested a complex linear systems approach, considerably different from the real-life situation. The stakeholders introduced bias to problem definition by transferring self-perceived issues onto the project owner. Application of soft systems methodology caused a shift in project goals away from further investigation towards consideration of project suitability. The challenge of sustainable hydropower is global, with a need to balance environmental, economic, and social concerns. It is clear that in this type of conflict, an individual can significantly influence outcomes; highlighting the need for more structured approaches to deal with stakeholder conflicts in sustainable hydropower development.

  16. Managing sustainable development conflicts: the impact of stakeholders in small-scale hydropower schemes.

    PubMed

    Watkin, Laura Jane; Kemp, Paul S; Williams, Ian D; Harwood, Ian A

    2012-06-01

    The growing importance of the environment and its management has simultaneously emphasized the benefits of hydroelectric power and its environmental costs. In a changing policy climate, giving importance to renewable energy development and environmental protection, conflict potential between stakeholders is considerable. Navigation of conflict determines the scheme constructed, making sustainable hydropower a function of human choice. To meet the needs of practitioners, greater understanding of stakeholder conflict is needed. This paper presents an approach to illustrate the challenges that face small-scale hydropower development as perceived by the stakeholders involved, and how they influence decision-making. Using Gordleton Mill, Hampshire (UK), as an illustrative case, soft systems methodology, a systems modeling approach, was adopted. Through individual interviews, a range of problems were identified and conceptually modeled. Stakeholder bias towards favoring economic appraisal over intangible social and environmental aspects was identified; costs appeared more influential than profit. Conceptual evaluation of the requirements to meet a stakeholder-approved solution suggested a complex linear systems approach, considerably different from the real-life situation. The stakeholders introduced bias to problem definition by transferring self-perceived issues onto the project owner. Application of soft systems methodology caused a shift in project goals away from further investigation towards consideration of project suitability. The challenge of sustainable hydropower is global, with a need to balance environmental, economic, and social concerns. It is clear that in this type of conflict, an individual can significantly influence outcomes; highlighting the need for more structured approaches to deal with stakeholder conflicts in sustainable hydropower development.

  17. Managing sustainable development conflicts: the impact of stakeholders in small-scale hydropower schemes.

    PubMed

    Watkin, Laura Jane; Kemp, Paul S; Williams, Ian D; Harwood, Ian A

    2012-06-01

    The growing importance of the environment and its management has simultaneously emphasized the benefits of hydroelectric power and its environmental costs. In a changing policy climate, giving importance to renewable energy development and environmental protection, conflict potential between stakeholders is considerable. Navigation of conflict determines the scheme constructed, making sustainable hydropower a function of human choice. To meet the needs of practitioners, greater understanding of stakeholder conflict is needed. This paper presents an approach to illustrate the challenges that face small-scale hydropower development as perceived by the stakeholders involved, and how they influence decision-making. Using Gordleton Mill, Hampshire (UK), as an illustrative case, soft systems methodology, a systems modeling approach, was adopted. Through individual interviews, a range of problems were identified and conceptually modeled. Stakeholder bias towards favoring economic appraisal over intangible social and environmental aspects was identified; costs appeared more influential than profit. Conceptual evaluation of the requirements to meet a stakeholder-approved solution suggested a complex linear systems approach, considerably different from the real-life situation. The stakeholders introduced bias to problem definition by transferring self-perceived issues onto the project owner. Application of soft systems methodology caused a shift in project goals away from further investigation towards consideration of project suitability. The challenge of sustainable hydropower is global, with a need to balance environmental, economic, and social concerns. It is clear that in this type of conflict, an individual can significantly influence outcomes; highlighting the need for more structured approaches to deal with stakeholder conflicts in sustainable hydropower development. PMID:22525992

  18. Evaluation of Injection Efficiency of Carbon Dioxide Using an Integrated Injection Well and Geologic Formation Numerical Simulation Scheme

    NASA Astrophysics Data System (ADS)

    Kihm, J.; Park, S.; Kim, J.; SNU CO2 GEO-SEQ TEAM

    2011-12-01

    A series of integrated injection well and geologic formation numerical simulations was performed to evaluate the injection efficiency of carbon dioxide using a multiphase thermo-hydrological numerical model. The numerical simulation results show that groundwater flow, carbon dioxide flow, and heat transport in both injection well and sandstone formation can be simultaneously analyzed, and thus the injection efficiency (i.e., injection rate and injectivity) of carbon dioxide can be quantitatively evaluated using the integrated injection well and geologic formation numerical simulation scheme. The injection rate and injectivity of carbon dioxide increase rapidly during the early period of time (about 10 days) and then increase slightly up to about 2.07 kg/s (equivalent to 0.065 Mton/year) and about 2.84 × 10-7 kg/s/Pa, respectively, until 10 years for the base case. The sensitivity test results show that the injection pressure and temperature of carbon dioxide at the wellhead have significant impacts on its injection rate and injectivity. The vertical profile of the fluid pressure in the injection well becomes almost a hydrostatical equilibrium state within 1 month for all the cases. The vertical profile of the fluid temperature in the injection well becomes a monotonously increasing profile with the depth due to isenthalpic or adiabatic compression within 6 months for all the cases. The injection rate of carbon dioxide increases linearly with the fluid pressure difference between the well bottom and the sandstone formation far from the injection well. In contrast, the injectivity of carbon dioxide varies unsystematically with the fluid pressure difference. On the other hand, the reciprocal of the kinematic viscosity of carbon dioxide at the well bottom has an excellent linear relationship with the injectivity of carbon dioxide. It indicates that the above-mentioned variation of the injectivity of carbon dioxide can be corrected using this linear relationship. The

  19. Eco-efficiency of solid waste management in Welsh SMEs

    NASA Astrophysics Data System (ADS)

    Sarkis, Joseph; Dijkshoorn, Jeroen

    2005-11-01

    This paper provides an efficiency analysis of practices in Solid Waste Management of manufacturing companies in Wales. We apply data envelopment analysis (DEA) to a data set compiled during the National Waste Survey Wales 2003. We explore the relative performance of small and medium sized manufacturing enterprises (SME; 10-250 employees) in Wales. We determine the technical and scale environmental and economic efficiencies of these organizations. Our evaluation focuses on empirical data collected from companies in a wide diversity of manufacturing industries throughout Wales. We find significant differences in industry and size efficiencies. We also find correlations that exist among environmental and economic efficiencies. These variations show that improvements can be made using benchmarks from similar and different size industries. Further pursuit of an investigation of possible reasons for these differences is recommended.

  20. Master-oscillator power-amplifier scheme for efficient green-light generation in a planar MgO:PPLN waveguide.

    PubMed

    Sakai, Kiyohide; Koyata, Yasuharu; Shimada, Naoyuki; Shibata, Kimitaka; Hanamaki, Yoshihiko; Itakura, Shigetaka; Yagi, Tetsuya; Hirano, Yoshihito

    2008-03-01

    We developed a new master-oscillator power-amplifier scheme consisting of a tapered semiconductor amplifier and a fiber-grating-stabilized laser diode for efficient green-light generation in a planar MgO:PPLN waveguide, and demonstrated cw green-light generation of 346 mW. PMID:18311282

  1. Efficient, adaptive energy stable schemes for the incompressible Cahn-Hilliard Navier-Stokes phase-field models

    NASA Astrophysics Data System (ADS)

    Chen, Ying; Shen, Jie

    2016-03-01

    In this paper we develop a fully adaptive energy stable scheme for Cahn-Hilliard Navier-Stokes system, which is a phase-field model for two-phase incompressible flows, consisting a Cahn-Hilliard-type diffusion equation and a Navier-Stokes equation. This scheme, which is decoupled and unconditionally energy stable based on stabilization, involves adaptive mesh, adaptive time and a nonlinear multigrid finite difference method. Numerical experiments are carried out to validate the scheme for problems with matched density and non-matched density, and also demonstrate that CPU time can be significantly reduced with our adaptive approach.

  2. Cooperative Game-Based Energy Efficiency Management over Ultra-Dense Wireless Cellular Networks.

    PubMed

    Li, Ming; Chen, Pengpeng; Gao, Shouwan

    2016-09-13

    Ultra-dense wireless cellular networks have been envisioned as a promising technique for handling the explosive increase of wireless traffic volume. With the extensive deployment of small cells in wireless cellular networks, the network spectral efficiency (SE) is improved with the use of limited frequency. However, the mutual inter-tier and intra-tier interference between or among small cells and macro cells becomes serious. On the other hand, more chances for potential cooperation among different cells are introduced. Energy efficiency (EE) has become one of the most important problems for future wireless networks. This paper proposes a cooperative bargaining game-based method for comprehensive EE management in an ultra-dense wireless cellular network, which highlights the complicated interference influence on energy-saving challenges and the power-coordination process among small cells and macro cells. Especially, a unified EE utility with the consideration of the interference mitigation is proposed to jointly address the SE, the deployment efficiency (DE), and the EE. In particular, closed-form power-coordination solutions for the optimal EE are derived to show the convergence property of the algorithm. Moreover, a simplified algorithm is presented to reduce the complexity of the signaling overhead, which is significant for ultra-dense small cells. Finally, numerical simulations are provided to illustrate the efficiency of the proposed cooperative bargaining game-based and simplified schemes.

  3. Cooperative Game-Based Energy Efficiency Management over Ultra-Dense Wireless Cellular Networks.

    PubMed

    Li, Ming; Chen, Pengpeng; Gao, Shouwan

    2016-01-01

    Ultra-dense wireless cellular networks have been envisioned as a promising technique for handling the explosive increase of wireless traffic volume. With the extensive deployment of small cells in wireless cellular networks, the network spectral efficiency (SE) is improved with the use of limited frequency. However, the mutual inter-tier and intra-tier interference between or among small cells and macro cells becomes serious. On the other hand, more chances for potential cooperation among different cells are introduced. Energy efficiency (EE) has become one of the most important problems for future wireless networks. This paper proposes a cooperative bargaining game-based method for comprehensive EE management in an ultra-dense wireless cellular network, which highlights the complicated interference influence on energy-saving challenges and the power-coordination process among small cells and macro cells. Especially, a unified EE utility with the consideration of the interference mitigation is proposed to jointly address the SE, the deployment efficiency (DE), and the EE. In particular, closed-form power-coordination solutions for the optimal EE are derived to show the convergence property of the algorithm. Moreover, a simplified algorithm is presented to reduce the complexity of the signaling overhead, which is significant for ultra-dense small cells. Finally, numerical simulations are provided to illustrate the efficiency of the proposed cooperative bargaining game-based and simplified schemes. PMID:27649170

  4. Cooperative Game-Based Energy Efficiency Management over Ultra-Dense Wireless Cellular Networks

    PubMed Central

    Li, Ming; Chen, Pengpeng; Gao, Shouwan

    2016-01-01

    Ultra-dense wireless cellular networks have been envisioned as a promising technique for handling the explosive increase of wireless traffic volume. With the extensive deployment of small cells in wireless cellular networks, the network spectral efficiency (SE) is improved with the use of limited frequency. However, the mutual inter-tier and intra-tier interference between or among small cells and macro cells becomes serious. On the other hand, more chances for potential cooperation among different cells are introduced. Energy efficiency (EE) has become one of the most important problems for future wireless networks. This paper proposes a cooperative bargaining game-based method for comprehensive EE management in an ultra-dense wireless cellular network, which highlights the complicated interference influence on energy-saving challenges and the power-coordination process among small cells and macro cells. Especially, a unified EE utility with the consideration of the interference mitigation is proposed to jointly address the SE, the deployment efficiency (DE), and the EE. In particular, closed-form power-coordination solutions for the optimal EE are derived to show the convergence property of the algorithm. Moreover, a simplified algorithm is presented to reduce the complexity of the signaling overhead, which is significant for ultra-dense small cells. Finally, numerical simulations are provided to illustrate the efficiency of the proposed cooperative bargaining game-based and simplified schemes. PMID:27649170

  5. Clinical information systems: cornerstone for an efficient hospital management.

    PubMed

    Lovis, Christian

    2011-01-01

    The university hospitals of Geneva are the largest consortium of public hospitals in Switzerland. This organization is born in 1995, after a political decision to merge the seven public and teaching hospitals of the Canton of Geneva. From an information technologies perspective, it took several years to reach a true unified vision of the complete organization. The clinical information system is deployed in all sites covering in- and outpatient cares. It is seen as the cornerstone of information management and flow in the organization, for direct patient care and decision support, but also for the management to drive, improve and leverage the activities, for better efficiency, quality and safety of care, but also to drive processes. As the system has become more important for the organization, it has required progressive changes in its governance. The high importance of interoperability and use of formal representation has become a major challenge in order to be able to reuse clinical information for real-time care and management activities, and for secondary usage such as billing, resource management, strategic planning and clinical research. This paper proposes a short overview of the tools allowing to leverage the management for physicians, nurses, human resources and hospital governance.

  6. Dynamic ocean management increases the efficiency and efficacy of fisheries management

    PubMed Central

    Maxwell, Sara M.; Halpin, Patrick N.

    2016-01-01

    In response to the inherent dynamic nature of the oceans and continuing difficulty in managing ecosystem impacts of fisheries, interest in the concept of dynamic ocean management, or real-time management of ocean resources, has accelerated in the last several years. However, scientists have yet to quantitatively assess the efficiency of dynamic management over static management. Of particular interest is how scale influences effectiveness, both in terms of how it reflects underlying ecological processes and how this relates to potential efficiency gains. Here, we address the empirical evidence gap and further the ecological theory underpinning dynamic management. We illustrate, through the simulation of closures across a range of spatiotemporal scales, that dynamic ocean management can address previously intractable problems at scales associated with coactive and social patterns (e.g., competition, predation, niche partitioning, parasitism, and social aggregations). Furthermore, it can significantly improve the efficiency of management: as the resolution of the closures used increases (i.e., as the closures become more targeted), the percentage of target catch forgone or displaced decreases, the reduction ratio (bycatch/catch) increases, and the total time–area required to achieve the desired bycatch reduction decreases. In the scenario examined, coarser scale management measures (annual time–area closures and monthly full-fishery closures) would displace up to four to five times the target catch and require 100–200 times more square kilometer-days of closure than dynamic measures (grid-based closures and move-on rules). To achieve similar reductions in juvenile bycatch, the fishery would forgo or displace between USD 15–52 million in landings using a static approach over a dynamic management approach. PMID:26729885

  7. Dynamic ocean management increases the efficiency and efficacy of fisheries management.

    PubMed

    Dunn, Daniel C; Maxwell, Sara M; Boustany, Andre M; Halpin, Patrick N

    2016-01-19

    In response to the inherent dynamic nature of the oceans and continuing difficulty in managing ecosystem impacts of fisheries, interest in the concept of dynamic ocean management, or real-time management of ocean resources, has accelerated in the last several years. However, scientists have yet to quantitatively assess the efficiency of dynamic management over static management. Of particular interest is how scale influences effectiveness, both in terms of how it reflects underlying ecological processes and how this relates to potential efficiency gains. Here, we address the empirical evidence gap and further the ecological theory underpinning dynamic management. We illustrate, through the simulation of closures across a range of spatiotemporal scales, that dynamic ocean management can address previously intractable problems at scales associated with coactive and social patterns (e.g., competition, predation, niche partitioning, parasitism, and social aggregations). Furthermore, it can significantly improve the efficiency of management: as the resolution of the closures used increases (i.e., as the closures become more targeted), the percentage of target catch forgone or displaced decreases, the reduction ratio (bycatch/catch) increases, and the total time-area required to achieve the desired bycatch reduction decreases. In the scenario examined, coarser scale management measures (annual time-area closures and monthly full-fishery closures) would displace up to four to five times the target catch and require 100-200 times more square kilometer-days of closure than dynamic measures (grid-based closures and move-on rules). To achieve similar reductions in juvenile bycatch, the fishery would forgo or displace between USD 15-52 million in landings using a static approach over a dynamic management approach. PMID:26729885

  8. Dynamic ocean management increases the efficiency and efficacy of fisheries management.

    PubMed

    Dunn, Daniel C; Maxwell, Sara M; Boustany, Andre M; Halpin, Patrick N

    2016-01-19

    In response to the inherent dynamic nature of the oceans and continuing difficulty in managing ecosystem impacts of fisheries, interest in the concept of dynamic ocean management, or real-time management of ocean resources, has accelerated in the last several years. However, scientists have yet to quantitatively assess the efficiency of dynamic management over static management. Of particular interest is how scale influences effectiveness, both in terms of how it reflects underlying ecological processes and how this relates to potential efficiency gains. Here, we address the empirical evidence gap and further the ecological theory underpinning dynamic management. We illustrate, through the simulation of closures across a range of spatiotemporal scales, that dynamic ocean management can address previously intractable problems at scales associated with coactive and social patterns (e.g., competition, predation, niche partitioning, parasitism, and social aggregations). Furthermore, it can significantly improve the efficiency of management: as the resolution of the closures used increases (i.e., as the closures become more targeted), the percentage of target catch forgone or displaced decreases, the reduction ratio (bycatch/catch) increases, and the total time-area required to achieve the desired bycatch reduction decreases. In the scenario examined, coarser scale management measures (annual time-area closures and monthly full-fishery closures) would displace up to four to five times the target catch and require 100-200 times more square kilometer-days of closure than dynamic measures (grid-based closures and move-on rules). To achieve similar reductions in juvenile bycatch, the fishery would forgo or displace between USD 15-52 million in landings using a static approach over a dynamic management approach.

  9. Long-term mortality of chest pain patients managed according to a decision scheme that aims to avoid inappropriate hospitalisations

    PubMed Central

    de Torbal, A.; Grijseels, E.W.M.; van Domburg, R.T.; Hartman, J.A.M.; Simoons, M.L.; Boersma, E.

    2003-01-01

    Objective A triage decision scheme was developed to avoid unnecessary hospitalisations for suspected acute coronary syndromes. The current investigation aimed at evaluating the long-term survival of patients who were managed according to this scheme. Subjects Patients (n=964) with symptoms suggestive of acute cardiac pathology, who were seen by a general practitioner, and for whom a pre-hospital ECG was recorded by the ambulance service in 1993-1994. Methods During the year 2000 a follow-up of the entire cohort was performed, and the vital status of patients was determined via the civil registry office. Cox's multivariable regression analyses were performed to evaluate the relation between final (hospital discharge) diagnosis and long-term outcome. Results The median follow-up was 6.0 years (4.6-6.6). Six-year mortality of the entire cohort was 30%. Long-term mortality was significantly lower in patients identified to be at low risk, who are not hospitalised, than in hospitalised patients (six-year mortality 7.5% versus 33.1%; p<0.0001). Longterm outcome was strongly associated with the final hospital discharge diagnosis. Conclusion Our data support the usefulness and appropriateness of the applied diagnostic scheme that aims to avoid unjustified hospital and CCU admissions in patients with acute chest pain. ImagesFigure 2 PMID:25696234

  10. An efficient high-order compact scheme for the unsteady compressible Euler and Navier-Stokes equations

    NASA Astrophysics Data System (ADS)

    Lerat, A.

    2016-10-01

    Residual-Based Compact (RBC) schemes approximate the 3-D compressible Euler equations with a 5th- or 7th-order accuracy on a 5 × 5 × 5-point stencil and capture shocks pretty well without correction. For unsteady flows however, they require a costly algebra to extract the time-derivative occurring at several places in the scheme. A new high-order time formulation has been recently proposed [13] for simplifying the RBC schemes and increasing their temporal accuracy. The present paper goes much further in this direction and deeply reconsiders the method. An avatar of the RBC schemes is presented that greatly reduces the computing time and the memory requirements while keeping the same type of successful numerical dissipation. Two and three-dimensional linear stability are analyzed and the method is extended to the 3-D compressible Navier-Stokes equations. The new compact scheme is validated for several unsteady problems in two and three dimension. In particular, an accurate DNS at moderate cost is presented for the evolution of the Taylor-Green Vortex at Reynolds 1600 and Prandtl 0.71. The effects of the mesh size and of the accuracy order in the approximation of Euler and viscous terms are discussed.

  11. Efficient and effective compound management to support lead optimization.

    PubMed

    Johnson, Chad W; Chatterjee, Moneesh; Kubala, Steve; Helm, David; Houston, John; Banks, Martyn

    2009-06-01

    The introduction of lean thinking and Six Sigma methodologies into the drug discovery process has become an important approach for ensuring efficient workflows while containing costs. For the compound management department at Bristol-Myers Squibb, this has resulted in a partnership with the research community to evaluate and streamline processes to enable cost-disciplined science. The authors describe the results of Lean Six Sigma approaches in the automation and informatics environment that have been optimized to support parallel processing of compounds. This new platform facilitates the rapid and simultaneous data generation from structure activity and structure liability assays. As a result of these compound management improvements, reduction of timelines and quicker decision making has been achieved in the lead optimization process.

  12. EM modelling of arbitrary shaped anisotropic dielectric objects using an efficient 3D leapfrog scheme on unstructured meshes

    NASA Astrophysics Data System (ADS)

    Gansen, A.; Hachemi, M. El; Belouettar, S.; Hassan, O.; Morgan, K.

    2016-09-01

    The standard Yee algorithm is widely used in computational electromagnetics because of its simplicity and divergence free nature. A generalization of the classical Yee scheme to 3D unstructured meshes is adopted, based on the use of a Delaunay primal mesh and its high quality Voronoi dual. This allows the problem of accuracy losses, which are normally associated with the use of the standard Yee scheme and a staircased representation of curved material interfaces, to be circumvented. The 3D dual mesh leapfrog-scheme which is presented has the ability to model both electric and magnetic anisotropic lossy materials. This approach enables the modelling of problems, of current practical interest, involving structured composites and metamaterials.

  13. BlueDetect: An iBeacon-Enabled Scheme for Accurate and Energy-Efficient Indoor-Outdoor Detection and Seamless Location-Based Service.

    PubMed

    Zou, Han; Jiang, Hao; Luo, Yiwen; Zhu, Jianjie; Lu, Xiaoxuan; Xie, Lihua

    2016-01-01

    The location and contextual status (indoor or outdoor) is fundamental and critical information for upper-layer applications, such as activity recognition and location-based services (LBS) for individuals. In addition, optimizations of building management systems (BMS), such as the pre-cooling or heating process of the air-conditioning system according to the human traffic entering or exiting a building, can utilize the information, as well. The emerging mobile devices, which are equipped with various sensors, become a feasible and flexible platform to perform indoor-outdoor (IO) detection. However, power-hungry sensors, such as GPS and WiFi, should be used with caution due to the constrained battery storage on mobile device. We propose BlueDetect: an accurate, fast response and energy-efficient scheme for IO detection and seamless LBS running on the mobile device based on the emerging low-power iBeacon technology. By leveraging the on-broad Bluetooth module and our proposed algorithms, BlueDetect provides a precise IO detection service that can turn on/off on-board power-hungry sensors smartly and automatically, optimize their performances and reduce the power consumption of mobile devices simultaneously. Moreover, seamless positioning and navigation services can be realized by it, especially in a semi-outdoor environment, which cannot be achieved by GPS or an indoor positioning system (IPS) easily. We prototype BlueDetect on Android mobile devices and evaluate its performance comprehensively. The experimental results have validated the superiority of BlueDetect in terms of IO detection accuracy, localization accuracy and energy consumption. PMID:26907295

  14. BlueDetect: An iBeacon-Enabled Scheme for Accurate and Energy-Efficient Indoor-Outdoor Detection and Seamless Location-Based Service

    PubMed Central

    Zou, Han; Jiang, Hao; Luo, Yiwen; Zhu, Jianjie; Lu, Xiaoxuan; Xie, Lihua

    2016-01-01

    The location and contextual status (indoor or outdoor) is fundamental and critical information for upper-layer applications, such as activity recognition and location-based services (LBS) for individuals. In addition, optimizations of building management systems (BMS), such as the pre-cooling or heating process of the air-conditioning system according to the human traffic entering or exiting a building, can utilize the information, as well. The emerging mobile devices, which are equipped with various sensors, become a feasible and flexible platform to perform indoor-outdoor (IO) detection. However, power-hungry sensors, such as GPS and WiFi, should be used with caution due to the constrained battery storage on mobile device. We propose BlueDetect: an accurate, fast response and energy-efficient scheme for IO detection and seamless LBS running on the mobile device based on the emerging low-power iBeacon technology. By leveraging the on-broad Bluetooth module and our proposed algorithms, BlueDetect provides a precise IO detection service that can turn on/off on-board power-hungry sensors smartly and automatically, optimize their performances and reduce the power consumption of mobile devices simultaneously. Moreover, seamless positioning and navigation services can be realized by it, especially in a semi-outdoor environment, which cannot be achieved by GPS or an indoor positioning system (IPS) easily. We prototype BlueDetect on Android mobile devices and evaluate its performance comprehensively. The experimental results have validated the superiority of BlueDetect in terms of IO detection accuracy, localization accuracy and energy consumption. PMID:26907295

  15. BlueDetect: An iBeacon-Enabled Scheme for Accurate and Energy-Efficient Indoor-Outdoor Detection and Seamless Location-Based Service.

    PubMed

    Zou, Han; Jiang, Hao; Luo, Yiwen; Zhu, Jianjie; Lu, Xiaoxuan; Xie, Lihua

    2016-02-22

    The location and contextual status (indoor or outdoor) is fundamental and critical information for upper-layer applications, such as activity recognition and location-based services (LBS) for individuals. In addition, optimizations of building management systems (BMS), such as the pre-cooling or heating process of the air-conditioning system according to the human traffic entering or exiting a building, can utilize the information, as well. The emerging mobile devices, which are equipped with various sensors, become a feasible and flexible platform to perform indoor-outdoor (IO) detection. However, power-hungry sensors, such as GPS and WiFi, should be used with caution due to the constrained battery storage on mobile device. We propose BlueDetect: an accurate, fast response and energy-efficient scheme for IO detection and seamless LBS running on the mobile device based on the emerging low-power iBeacon technology. By leveraging the on-broad Bluetooth module and our proposed algorithms, BlueDetect provides a precise IO detection service that can turn on/off on-board power-hungry sensors smartly and automatically, optimize their performances and reduce the power consumption of mobile devices simultaneously. Moreover, seamless positioning and navigation services can be realized by it, especially in a semi-outdoor environment, which cannot be achieved by GPS or an indoor positioning system (IPS) easily. We prototype BlueDetect on Android mobile devices and evaluate its performance comprehensively. The experimental results have validated the superiority of BlueDetect in terms of IO detection accuracy, localization accuracy and energy consumption.

  16. Image reconstruction scheme that combines modified Newton method and efficient initial guess estimation for optical tomography of finger joints.

    PubMed

    Yuan, Zhen; Jiang, Huabei

    2007-05-10

    What we believe to be a novel 3D diffuse optical tomography scheme is developed to reconstruct images of both absorption and scattering coefficients of finger joint systems. Compared with our previous reconstruction method, the improved 3D algorithm employs both modified Newton methods and an enhanced initial value optimization scheme to recover the optical properties of highly heterogeneous media. The developed approach is tested using simulated, phantom, and in vivo measurement data. The recovered results suggest that the improved approach is able to provide quantitatively better images than our previous algorithm for optical tomography reconstruction.

  17. Comparing Nitrous Oxide Emissions from Three Residential Landscapes under Different Management Schemes Following Natural Rainfall Events

    EPA Science Inventory

    Cultural lawn management practices that produce aesthetically appealing landscapes may also create environmental conditions that stimulate soil nitrous oxide (N2O) emissions. The purpose of this study is to investigate the effects of lawn management practices on N2O fluxes from ...

  18. A distributed scheme to manage the dynamic coexistence of IEEE 802.15.4-based health-monitoring WBANs.

    PubMed

    Deylami, Mohammad N; Jovanov, Emil

    2014-01-01

    The overlap of transmission ranges between wireless networks as a result of mobility is referred to as dynamic coexistence. The interference caused by coexistence may significantly affect the performance of wireless body area networks (WBANs) where reliability is particularly critical for health monitoring applications. In this paper, we analytically study the effects of dynamic coexistence on the operation of IEEE 802.15.4-based health monitoring WBANs. The current IEEE 802.15.4 standard lacks mechanisms for effectively managing the coexistence of mobile WBANs. Considering the specific characteristics and requirements of health monitoring WBANs, we propose the dynamic coexistence management (DCM) mechanism to make IEEE 802.15.4-based WBANs able to detect and mitigate the harmful effects of coexistence. We assess the effectiveness of this scheme using extensive OPNET simulations. Our results indicate that DCM improves the successful transmission rates of dynamically coexisting WBANs by 20%-25% for typical medical monitoring applications.

  19. Brillouin-zone integration schemes: an efficiency study for the phonon frequency moments of the harmonic, solid, one-component plasma

    SciTech Connect

    Albers, R.C.; Gubernatis, J.E.

    1981-01-01

    The efficiency of four different Brillouin-zone integration schemes including the uniform mesh, special point method, special directions method, and Holas method are compared for calculating moments of the harmonic phonon frequencies of the solid one-component plasma. Very accurate values for the moments are also presented. The Holas method for which weights and integration points can easily be generated has roughly the same efficiency as the special directions method, which is much superior to the uniform mesh and special point methods for this problem.

  20. A computationally efficient scheme for the inversion of large scale potential field data: Application to synthetic and real data

    NASA Astrophysics Data System (ADS)

    Wang, Jun; Meng, Xiaohong; Li, Fang

    2015-12-01

    Three dimensional (3D) inversion of potential field data from large scale surveys attempts to recover density or magnetic susceptibility distribution in the subspace for geological interpretation. It is computationally challenging and is not feasible on desktop computers. We propose an integrated scheme to address this problem. We adopt adaptive sampling to compress the dataset, and the cross curve of the data compression ratio and correlation coefficient between the initial and sampled data is used to choose the damping factor for adaptive sampling. Then, the conventional inversion algorithm in model space is transformed to data space, using the identity relationship between different matrices, which greatly reduces the memory requirement. Finally, parallel computation is employed to accelerate calculation of the kernel function. We use the conjugate gradient method to minimize the objective function and a damping factor is introduced to stabilize the iterative process. A wide variety of constraint options are also considered, such as depth weighing, sparseness, and boundary limits. We design a synthetic magnetic model with three prismatic susceptibility causative bodies to demonstrate the effectiveness of the proposed scheme. Tests on synthetic data show that the proposed scheme provides significant reduction in memory and time consumption, and the inversion result is reliable. These advantages hold true for practical field magnetic data from the Hawsons mining area in Australia, verifying the effectiveness of the proposed scheme.

  1. Efficiency and Flexibility of Fingerprint Scheme Using Partial Encryption and Discrete Wavelet Transform to Verify User in Cloud Computing

    PubMed Central

    Yassin, Ali A.

    2014-01-01

    Now, the security of digital images is considered more and more essential and fingerprint plays the main role in the world of image. Furthermore, fingerprint recognition is a scheme of biometric verification that applies pattern recognition techniques depending on image of fingerprint individually. In the cloud environment, an adversary has the ability to intercept information and must be secured from eavesdroppers. Unluckily, encryption and decryption functions are slow and they are often hard. Fingerprint techniques required extra hardware and software; it is masqueraded by artificial gummy fingers (spoof attacks). Additionally, when a large number of users are being verified at the same time, the mechanism will become slow. In this paper, we employed each of the partial encryptions of user's fingerprint and discrete wavelet transform to obtain a new scheme of fingerprint verification. Moreover, our proposed scheme can overcome those problems; it does not require cost, reduces the computational supplies for huge volumes of fingerprint images, and resists well-known attacks. In addition, experimental results illustrate that our proposed scheme has a good performance of user's fingerprint verification. PMID:27355051

  2. Efficient Mobility Management Signalling in Network Mobility Supported PMIPV6

    PubMed Central

    Jebaseeli Samuelraj, Ananthi; Jayapal, Sundararajan

    2015-01-01

    Proxy Mobile IPV6 (PMIPV6) is a network based mobility management protocol which supports node's mobility without the contribution from the respective mobile node. PMIPV6 is initially designed to support individual node mobility and it should be enhanced to support mobile network movement. NEMO-BSP is an existing protocol to support network mobility (NEMO) in PMIPV6 network. Due to the underlying differences in basic protocols, NEMO-BSP cannot be directly applied to PMIPV6 network. Mobility management signaling and data structures used for individual node's mobility should be modified to support group nodes' mobility management efficiently. Though a lot of research work is in progress to implement mobile network movement in PMIPV6, it is not yet standardized and each suffers with different shortcomings. This research work proposes modifications in NEMO-BSP and PMIPV6 to achieve NEMO support in PMIPV6. It mainly concentrates on optimizing the number and size of mobility signaling exchanged while mobile network or mobile network node changes its access point. PMID:26366431

  3. Efficient Mobility Management Signalling in Network Mobility Supported PMIPV6.

    PubMed

    Samuelraj, Ananthi Jebaseeli; Jayapal, Sundararajan

    2015-01-01

    Proxy Mobile IPV6 (PMIPV6) is a network based mobility management protocol which supports node's mobility without the contribution from the respective mobile node. PMIPV6 is initially designed to support individual node mobility and it should be enhanced to support mobile network movement. NEMO-BSP is an existing protocol to support network mobility (NEMO) in PMIPV6 network. Due to the underlying differences in basic protocols, NEMO-BSP cannot be directly applied to PMIPV6 network. Mobility management signaling and data structures used for individual node's mobility should be modified to support group nodes' mobility management efficiently. Though a lot of research work is in progress to implement mobile network movement in PMIPV6, it is not yet standardized and each suffers with different shortcomings. This research work proposes modifications in NEMO-BSP and PMIPV6 to achieve NEMO support in PMIPV6. It mainly concentrates on optimizing the number and size of mobility signaling exchanged while mobile network or mobile network node changes its access point.

  4. Efficient Mobility Management Signalling in Network Mobility Supported PMIPV6.

    PubMed

    Samuelraj, Ananthi Jebaseeli; Jayapal, Sundararajan

    2015-01-01

    Proxy Mobile IPV6 (PMIPV6) is a network based mobility management protocol which supports node's mobility without the contribution from the respective mobile node. PMIPV6 is initially designed to support individual node mobility and it should be enhanced to support mobile network movement. NEMO-BSP is an existing protocol to support network mobility (NEMO) in PMIPV6 network. Due to the underlying differences in basic protocols, NEMO-BSP cannot be directly applied to PMIPV6 network. Mobility management signaling and data structures used for individual node's mobility should be modified to support group nodes' mobility management efficiently. Though a lot of research work is in progress to implement mobile network movement in PMIPV6, it is not yet standardized and each suffers with different shortcomings. This research work proposes modifications in NEMO-BSP and PMIPV6 to achieve NEMO support in PMIPV6. It mainly concentrates on optimizing the number and size of mobility signaling exchanged while mobile network or mobile network node changes its access point. PMID:26366431

  5. Participatory innovation process for testing new practices for soil fertility management in Chókwè Irrigation Scheme (Mozambique)

    NASA Astrophysics Data System (ADS)

    Sánchez Reparaz, Maite; de Vente, Joris; Famba, Sebastiao; Rougier, Jean-Emmanuel; Ángel Sánchez-Monedero, Miguel; Barberá, Gonzalo G.

    2015-04-01

    Integrated water and nutrient management are key factors to increase productivity and to reduce the yield gap in irrigated systems in Sub-Saharan Africa. These two elements are affected by an ensemble of abiotic, biotic, management and socio-economic factors that need to be taken into account to reduce the yield gap, as well as farmers' perceptions and knowledge. In the framework of the project European Union and African Union cooperative research to increase Food production in irrigated farming systems in Africa (EAU4Food project) we are carrying out a participatory innovation process in Chókwè irrigation scheme (Mozambique) based on stakeholders engagement, to test new practices for soil fertility management that can increase yields reducing costs. Through a method combining interviews with three farmers' associations and other relevant stakeholders and soil sampling from the interviewed farmers' plots with the organization of Communities of Practices, we tried to capture how soil fertility is managed by farmers, the constraints they find as well as their perceptions about soil resources. This information was the basis to design and conduct a participatory innovation process where compost made with rice straw and manure is being tested by a farmers' association. Most important limitations of the method are also evaluated. Our results show that socio-economic characteristics of farmers condition how they manage soil fertility and their perceptions. The difficulties they face to adopt new practices for soil fertility management, mainly related to economic resources limitations, labour availability, knowledge time or farm structure, require a systemic understanding that takes into account abiotic, biotic, management and socio-economic factors and their implication as active stakeholders in all phases of the innovation process.

  6. Management of Universal Basic Education Scheme (U.B.E.) for Qualitative Education in Nigeria

    ERIC Educational Resources Information Center

    Omotayo, Dare Michael; Ihebereme, Chioma; Maduewesi, Sir B. U.

    2008-01-01

    Since independence, Nigeria has been searching diligently for a viable educational system capable of enhancing the socio-economic and political values inherent in the country. This paper discusses concepts such as management, qualitative education and Universal Basic Education. In addition to the above, the paper also examines the National…

  7. Analog-model simulations for secondary canal controls and forward pumping water-management schemes in southeast Florida

    USGS Publications Warehouse

    Cordes, E.H.; Gardner, Richard Alfred

    1976-01-01

    The analog model of the Biscayne aquifer of southeast Florida was used to approximate the effects of two proposed water-management schemes. One involved adding a secondary control structure in a major canal which is controlled near the coast. In the model the controls were operated in accordance with canal water level both above and below the secondary control. Although the model could not differentiate between control openings of 1 foot or 5 feet, it showed that the secondary control is a viable method of conserving ground water. The second scheme involved pumping ground water ('forward pumping') from the Biscayne aquifer in inland areas during the dry season to: (1) augment canal flows toward the coast to sustain ground-water levels there, and (2) generate additional ground-water storage space for recharge in the wet season. Several sites on the model were programmed for forward pumping wells and the storage change was noted as a percentage of the ground-water withdrawal. (Woodard-USGS)

  8. Innovative Technologies for Efficient Pharmacotherapeutic Management in Space

    NASA Technical Reports Server (NTRS)

    Putcha, Lakshmi; Daniels, Vernie

    2014-01-01

    Current and future Space exploration missions and extended human presence in space aboard the ISS will expose crew to risks that differ both quantitatively and qualitatively from those encountered before by space travelers and will impose an unknown risk of safety and crew health. The technology development challenges for optimizing therapeutics in space must include the development of pharmaceuticals with extended stability, optimal efficacy and bioavailability with minimal toxicity and side effects. Innovative technology development goals may include sustained/chronic delivery preventive health care products and vaccines, low-cost high-efficiency noninvasive, non-oral dosage forms with radio-protective formulation matrices and dispensing technologies coupled with self-reliant tracking technologies for quality assurance and quality control assessment. These revolutionary advances in pharmaceutical technology will assure human presence in space and healthy living on Earth. Additionally, the Joint Commission on Accreditation of Healthcare Organizations advocates the use of health information technologies to effectively execute all aspects of medication management (prescribing, dispensing, and administration). The advent of personalized medicine and highly streamlined treatment regimens stimulated interest in new technologies for medication management. Intelligent monitoring devices enhance medication accountability compliance, enable effective drug use, and offer appropriate storage and security conditions for dangerous drug and controlled substance medications in remote sites where traditional pharmacies are unavailable. These features are ideal for Exploration Medical Capabilities. This presentation will highlight current novel commercial off-the-shelf (COTS) intelligent medication management devices for the unique dispensing, therapeutic drug monitoring, medication tracking, and drug delivery demands of exploration space medical operations.

  9. An efficient light trapping scheme based on textured conductive photonic crystal back reflector for performance improvement of amorphous silicon solar cells

    SciTech Connect

    Chen, Peizhuan; Hou, Guofu Huang, Qian; Zhao, Jing; Zhang, Jianjun Ni, Jian; Zhang, Xiaodan; Zhao, Ying; Fan, QiHua

    2014-08-18

    An efficient light trapping scheme named as textured conductive photonic crystal (TCPC) has been proposed and then applied as a back-reflector (BR) in n-i-p hydrogenated amorphous silicon (a-Si:H) solar cell. This TCPC BR combined a flat one-dimensional photonic crystal and a randomly textured surface of chemically etched ZnO:Al. Total efficiency enhancement was obtained thanks to the sufficient conductivity, high reflectivity and strong light scattering of the TCPC BR. Unwanted intrinsic losses of surface plasmon modes are avoided. An initial efficiency of 9.66% for a-Si:H solar cell was obtained with short-circuit current density of 14.74 mA/cm{sup 2}, fill factor of 70.3%, and open-circuit voltage of 0.932 V.

  10. Reviewing the economic efficiency of disaster risk management

    NASA Astrophysics Data System (ADS)

    Mechler, Reinhard

    2013-04-01

    There is a lot of rhetoric suggesting that disaster risk management (DRM) pays, yet surprisingly little in the way of hard facts. Cost-benefit analysis (CBA) is one major tool that can provide quantitative information about the prioritization of disaster risk management (DRM) (and climate adaptation) based on economic principles. Yet, on a global scale, there has been surprisingly little robust evidence on the economic efficiency and benefits of risk management measures. This review shows that for the limited evidence reported the economic case for DRM across a range of hazards is strong and that the benefits of investing in DRM outweigh the costs of doing so, on average, by about four times the cost in terms of avoided and reduced losses. Most studies using a CBA approach focus on structural DRM and most information has been made available on physical flood prevention. There have been some limited studies on preparedness and risk financing. The global evidence base is limited and estimates appear not very solid, and overall, in line with the conclusion of the recent IPCC SREX report, there is limited evidence and medium agreement across the literature. Some of the factors behind the limited robustness are inherent to CBA more widely: these challenges comprise the inability to price intangibles, evaluating strategies rather than single projects, difficulties in assessing softer rather than infrastructure-related options, choices regarding a proper discount rate, lack of accounting for the distribution of benefits and costs and difficulties with assessing nonmarket values such as those related to health, the environment, or public goods. Although techniques exist to address some of these challenges, they are not very likely to easily go away. Other challenges associated specifically with DRM, such as the need and difficulty to undertake risk -based analysis can be overcome, and there have been manuals and reports providing a way forward. In an age of austerity, cost

  11. Home is where the hearth is: grant recipients' views of England's home energy efficiency scheme (Warm Front).

    PubMed

    Gilbertson, Jan; Stevens, Maryjane; Stiell, Bernadette; Thorogood, Nicki

    2006-08-01

    This paper reports the results of research carried out as part of the national health impact evaluation of the Warm Front Scheme, a government initiative aimed at alleviating fuel poverty in England. Semi-structured interviews were carried out in a purposive sample of 49 households which received home energy improvements under the Scheme from five urban areas (Birmingham, Liverpool, Manchester, Newcastle, Southampton). Each household had received installation, replacement or refurbishment of the heating system and, in some cases, also insulation of the cavity wall or loft or both, and draught-proofing measures. Most householders reported improved and more controllable warmth and hot water. Many also reported perceptions of improved physical health and comfort, especially of mental health and emotional well-being and, in several cases, the easing of symptoms of chronic illness. There were reports of improved family relations, an expansion of the domestic space used during cold months, greater use of kitchens and improved nutrition, increased privacy, improved social interaction, and an increase in comfort and atmosphere within the home. Greater warmth and comfort also enhanced emotional security, and recipients were more content and at ease in their homes. However there was little evidence of substantially lower heating bills. These results provide evidence that Warm Front home energy improvements are accompanied by appreciable benefits in terms of use of living space, comfort and quality of life, physical and mental well-being, although there is only limited evidence of change in health behaviour. PMID:16616807

  12. A mesh adaptivity scheme on the Landau-de Gennes functional minimization case in 3D, and its driving efficiency

    NASA Astrophysics Data System (ADS)

    Bajc, Iztok; Hecht, Frédéric; Žumer, Slobodan

    2016-09-01

    This paper presents a 3D mesh adaptivity strategy on unstructured tetrahedral meshes by a posteriori error estimates based on metrics derived from the Hessian of a solution. The study is made on the case of a nonlinear finite element minimization scheme for the Landau-de Gennes free energy functional of nematic liquid crystals. Newton's iteration for tensor fields is employed with steepest descent method possibly stepping in. Aspects relating the driving of mesh adaptivity within the nonlinear scheme are considered. The algorithmic performance is found to depend on at least two factors: when to trigger each single mesh adaptation, and the precision of the correlated remeshing. Each factor is represented by a parameter, with its values possibly varying for every new mesh adaptation. We empirically show that the time of the overall algorithm convergence can vary considerably when different sequences of parameters are used, thus posing a question about optimality. The extensive testings and debugging done within this work on the simulation of systems of nematic colloids substantially contributed to the upgrade of an open source finite element-oriented programming language to its 3D meshing possibilities, as also to an outer 3D remeshing module.

  13. An efficient and stable hybrid extended Lagrangian/self-consistent field scheme for solving classical mutual induction

    NASA Astrophysics Data System (ADS)

    Albaugh, Alex; Demerdash, Omar; Head-Gordon, Teresa

    2015-11-01

    We have adapted a hybrid extended Lagrangian self-consistent field (EL/SCF) approach, developed for time reversible Born Oppenheimer molecular dynamics for quantum electronic degrees of freedom, to the problem of classical polarization. In this context, the initial guess for the mutual induction calculation is treated by auxiliary induced dipole variables evolved via a time-reversible velocity Verlet scheme. However, we find numerical instability, which is manifested as an accumulation in the auxiliary velocity variables, that in turn results in an unacceptable increase in the number of SCF cycles to meet even loose convergence tolerances for the real induced dipoles over the course of a 1 ns trajectory of the AMOEBA14 water model. By diagnosing the numerical instability as a problem of resonances that corrupt the dynamics, we introduce a simple thermostating scheme, illustrated using Berendsen weak coupling and Nose-Hoover chain thermostats, applied to the auxiliary dipole velocities. We find that the inertial EL/SCF (iEL/SCF) method provides superior energy conservation with less stringent convergence thresholds and a correspondingly small number of SCF cycles, to reproduce all properties of the polarization model in the NVT and NVE ensembles accurately. Our iEL/SCF approach is a clear improvement over standard SCF approaches to classical mutual induction calculations and would be worth investigating for application to ab initio molecular dynamics as well.

  14. Home is where the hearth is: grant recipients' views of England's home energy efficiency scheme (Warm Front).

    PubMed

    Gilbertson, Jan; Stevens, Maryjane; Stiell, Bernadette; Thorogood, Nicki

    2006-08-01

    This paper reports the results of research carried out as part of the national health impact evaluation of the Warm Front Scheme, a government initiative aimed at alleviating fuel poverty in England. Semi-structured interviews were carried out in a purposive sample of 49 households which received home energy improvements under the Scheme from five urban areas (Birmingham, Liverpool, Manchester, Newcastle, Southampton). Each household had received installation, replacement or refurbishment of the heating system and, in some cases, also insulation of the cavity wall or loft or both, and draught-proofing measures. Most householders reported improved and more controllable warmth and hot water. Many also reported perceptions of improved physical health and comfort, especially of mental health and emotional well-being and, in several cases, the easing of symptoms of chronic illness. There were reports of improved family relations, an expansion of the domestic space used during cold months, greater use of kitchens and improved nutrition, increased privacy, improved social interaction, and an increase in comfort and atmosphere within the home. Greater warmth and comfort also enhanced emotional security, and recipients were more content and at ease in their homes. However there was little evidence of substantially lower heating bills. These results provide evidence that Warm Front home energy improvements are accompanied by appreciable benefits in terms of use of living space, comfort and quality of life, physical and mental well-being, although there is only limited evidence of change in health behaviour.

  15. An efficient and stable hybrid extended Lagrangian/self-consistent field scheme for solving classical mutual induction

    SciTech Connect

    Albaugh, Alex; Demerdash, Omar; Head-Gordon, Teresa

    2015-11-07

    We have adapted a hybrid extended Lagrangian self-consistent field (EL/SCF) approach, developed for time reversible Born Oppenheimer molecular dynamics for quantum electronic degrees of freedom, to the problem of classical polarization. In this context, the initial guess for the mutual induction calculation is treated by auxiliary induced dipole variables evolved via a time-reversible velocity Verlet scheme. However, we find numerical instability, which is manifested as an accumulation in the auxiliary velocity variables, that in turn results in an unacceptable increase in the number of SCF cycles to meet even loose convergence tolerances for the real induced dipoles over the course of a 1 ns trajectory of the AMOEBA14 water model. By diagnosing the numerical instability as a problem of resonances that corrupt the dynamics, we introduce a simple thermostating scheme, illustrated using Berendsen weak coupling and Nose-Hoover chain thermostats, applied to the auxiliary dipole velocities. We find that the inertial EL/SCF (iEL/SCF) method provides superior energy conservation with less stringent convergence thresholds and a correspondingly small number of SCF cycles, to reproduce all properties of the polarization model in the NVT and NVE ensembles accurately. Our iEL/SCF approach is a clear improvement over standard SCF approaches to classical mutual induction calculations and would be worth investigating for application to ab initio molecular dynamics as well.

  16. An efficient finite-difference scheme for computation of electron states in free-standing and core-shell quantum wires

    NASA Astrophysics Data System (ADS)

    Arsoski, V. V.; Čukarić, N. A.; Tadić, M. Ž.; Peeters, F. M.

    2015-12-01

    The electron states in axially symmetric quantum wires are computed by means of the effective-mass Schrödinger equation, which is written in cylindrical coordinates φ, ρ, and z. We show that a direct discretization of the Schrödinger equation by central finite differences leads to a non-symmetric Hamiltonian matrix. Because diagonalization of such matrices is more complex it is advantageous to transform it in a symmetric form. This can be done by the Liouville-like transformation proposed by Rizea et al. (2008), which replaces the wave function ψ(ρ) with the function F(ρ) = ψ(ρ) √{ ρ } and transforms the Hamiltonian accordingly. Even though a symmetric Hamiltonian matrix is produced by this procedure, the computed wave functions are found to be inaccurate near the origin, and the accuracy of the energy levels is not very high. In order to improve on this, we devised a finite-difference scheme which discretizes the Schrödinger equation in the first step, and then applies the Liouville-like transformation to the difference equation. Such a procedure gives a symmetric Hamiltonian matrix, resulting in an accuracy comparable to the one obtained with the finite element method. The superior efficiency of the new finite-difference scheme (FDM) is demonstrated for a few ρ-dependent one-dimensional potentials which are usually employed to model the electron states in free-standing and core-shell quantum wires. The new scheme is compared with the other FDM schemes for solving the effective-mass Schrödinger equation, and is found to deliver energy levels with much smaller numerical error for all the analyzed potentials. It also gives more accurate results than the scheme of Rizea et al., except for the ground state of an infinite rectangular potential in freestanding quantum wires. Moreover, the PT symmetry is invoked to explain similarities and differences between the considered FDM schemes.

  17. An adaptive undersampling scheme of wavelet-encoded parallel MR imaging for more efficient MR data acquisition

    NASA Astrophysics Data System (ADS)

    Xie, Hua; Bosshard, John C.; Hill, Jason E.; Wright, Steven M.; Mitra, Sunanda

    2016-03-01

    Magnetic Resonance Imaging (MRI) offers noninvasive high resolution, high contrast cross-sectional anatomic images through the body. The data of the conventional MRI is collected in spatial frequency (Fourier) domain, also known as kspace. Because there is still a great need to improve temporal resolution of MRI, Compressed Sensing (CS) in MR imaging is proposed to exploit the sparsity of MR images showing great potential to reduce the scan time significantly, however, it poses its own unique problems. This paper revisits wavelet-encoded MR imaging which replaces phase encoding in conventional MRI data acquisition with wavelet encoding by applying wavelet-shaped spatially selective radiofrequency (RF) excitation, and keeps the readout direction as frequency encoding. The practicality of wavelet encoded MRI by itself is limited due to the SNR penalties and poor time resolution compared to conventional Fourier-based MRI. To compensate for those disadvantages, this paper first introduces an undersampling scheme named significance map for sparse wavelet-encoded k-space to speed up data acquisition as well as allowing for various adaptive imaging strategies. The proposed adaptive wavelet-encoded undersampling scheme does not require prior knowledge of the subject to be scanned. Multiband (MB) parallel imaging is also incorporated with wavelet-encoded MRI by exciting multiple regions simultaneously for further reduction in scan time desirable for medical applications. The simulation and experimental results are presented showing the feasibility of the proposed approach in further reduction of the redundancy of the wavelet k-space data while maintaining relatively high quality.

  18. Efficient Z-scheme photocatalyst from simultaneous decoration of In2S3 nanosheets and WO3 nanorods on graphene sheets

    NASA Astrophysics Data System (ADS)

    Zhang, Qingran; Luo, Mingbo; Sun, Ya-Ping; Liu, Yuanfang; Cao, Aoneng

    2016-07-01

    Inspired by natural photosynthesis, the Z-scheme photocatalyst is a promising approach to extend the absorption spectra of photocatalysts and reduce the recombination of photo-generated electrons and holes. However, the fabrication of well-structured efficient multi-component Z-scheme photocatalysts is still a big challenge. We report here a facile one-pot method to synthesize graphene-based Z-scheme photocatalysts. The one-pot method guarantees good distribution of well-structured individual components on thin-layered rGO sheets with excellent connections. With inactive WO3 nanorods and inactive β-In2S3 nanosheets attached to the surface of the rGO sheets, the synthesized In2S3/WO3/rGO tertiary nanocomposite shows excellent visible-light catalytic activity for hydrogen production at 1524 μmol g‑1 h‑1, demonstrating unambiguously the Z-scheme catalytic mechanism. To prevent cross-reactions and interferences, our strategy was to choose no more than one ionic precipitation reaction for the one-pot process, as unwanted cross-reactions could become inevitable if many cations and anions were present. This fabrication strategy should be applicable generally to synthesize other multiple-component nanocomposites, as demonstrated also by the preliminary results of the successful synthesis of the BiVO4/WO3/rGO nanocomposite (one ionic precipitation reaction and one hydrolysis reaction) and WO3/TiO2/rGO nanocomposite (two hydrolysis reactions).

  19. Efficient Z-scheme photocatalyst from simultaneous decoration of In2S3 nanosheets and WO3 nanorods on graphene sheets.

    PubMed

    Zhang, Qingran; Luo, Mingbo; Sun, Ya-Ping; Liu, Yuanfang; Cao, Aoneng

    2016-07-15

    Inspired by natural photosynthesis, the Z-scheme photocatalyst is a promising approach to extend the absorption spectra of photocatalysts and reduce the recombination of photo-generated electrons and holes. However, the fabrication of well-structured efficient multi-component Z-scheme photocatalysts is still a big challenge. We report here a facile one-pot method to synthesize graphene-based Z-scheme photocatalysts. The one-pot method guarantees good distribution of well-structured individual components on thin-layered rGO sheets with excellent connections. With inactive WO3 nanorods and inactive β-In2S3 nanosheets attached to the surface of the rGO sheets, the synthesized In2S3/WO3/rGO tertiary nanocomposite shows excellent visible-light catalytic activity for hydrogen production at 1524 μmol g(-1) h(-1), demonstrating unambiguously the Z-scheme catalytic mechanism. To prevent cross-reactions and interferences, our strategy was to choose no more than one ionic precipitation reaction for the one-pot process, as unwanted cross-reactions could become inevitable if many cations and anions were present. This fabrication strategy should be applicable generally to synthesize other multiple-component nanocomposites, as demonstrated also by the preliminary results of the successful synthesis of the BiVO4/WO3/rGO nanocomposite (one ionic precipitation reaction and one hydrolysis reaction) and WO3/TiO2/rGO nanocomposite (two hydrolysis reactions).

  20. Efficient Z-scheme photocatalyst from simultaneous decoration of In2S3 nanosheets and WO3 nanorods on graphene sheets

    NASA Astrophysics Data System (ADS)

    Zhang, Qingran; Luo, Mingbo; Sun, Ya-Ping; Liu, Yuanfang; Cao, Aoneng

    2016-07-01

    Inspired by natural photosynthesis, the Z-scheme photocatalyst is a promising approach to extend the absorption spectra of photocatalysts and reduce the recombination of photo-generated electrons and holes. However, the fabrication of well-structured efficient multi-component Z-scheme photocatalysts is still a big challenge. We report here a facile one-pot method to synthesize graphene-based Z-scheme photocatalysts. The one-pot method guarantees good distribution of well-structured individual components on thin-layered rGO sheets with excellent connections. With inactive WO3 nanorods and inactive β-In2S3 nanosheets attached to the surface of the rGO sheets, the synthesized In2S3/WO3/rGO tertiary nanocomposite shows excellent visible-light catalytic activity for hydrogen production at 1524 μmol g-1 h-1, demonstrating unambiguously the Z-scheme catalytic mechanism. To prevent cross-reactions and interferences, our strategy was to choose no more than one ionic precipitation reaction for the one-pot process, as unwanted cross-reactions could become inevitable if many cations and anions were present. This fabrication strategy should be applicable generally to synthesize other multiple-component nanocomposites, as demonstrated also by the preliminary results of the successful synthesis of the BiVO4/WO3/rGO nanocomposite (one ionic precipitation reaction and one hydrolysis reaction) and WO3/TiO2/rGO nanocomposite (two hydrolysis reactions).

  1. Position statement on efficiency of technologies for diabetes management.

    PubMed

    Martín-Vaquero, Pilar; Martínez-Brocca, María Asunción; García-López, José Manuel

    2014-12-01

    Di@bet.es study results are impressive, showing that diabetes affects 13.8% of the Spanish population. Not only the statistical facts are alarming, but the increasing incidence of this disease is a major problem, as pandemic proportions of type 2 diabetes are expected. Thus, the study of diabetes represents a challenge not only for health services, but also for the Ministries of Health and Finance. Technology has become an essential tool in the quality are of patients with diabetes, as it helps in the healthcare processes to obtain an optimum metabolic balance and prevent possible complications. Insulin pumps, continuous glucose monitoring nd self-monitoring blood glucose have all proved their efficiency, and telemedicine it is making good progress. The indirect costs of diabetes in Spain are much higher than the directones, showing the importance of inverting the paradox. The optimization of resources depends not only on the ability of the physicians, but also the administration, to implant and sustain technological innovations in our system, and with that make it effective in terms of benefits. Cost-effectiveness and cost-utility analysis are needed to prioritize and allow health management services to make the correct choices for approaching this prevalent chronic disease.

  2. Position statement on efficiency of technologies for diabetes management.

    PubMed

    Martín-Vaquero, Pilar; Martínez-Brocca, María Asunción; García-López, José Manuel

    2014-12-01

    Di@bet.es study results are impressive, showing that diabetes affects 13.8% of the Spanish population. Not only the statistical facts are alarming, but the increasing incidence of this disease is a major problem, as pandemic proportions of type 2 diabetes are expected. Thus, the study of diabetes represents a challenge not only for health services, but also for the Ministries of Health and Finance. Technology has become an essential tool in the quality are of patients with diabetes, as it helps in the healthcare processes to obtain an optimum metabolic balance and prevent possible complications. Insulin pumps, continuous glucose monitoring nd self-monitoring blood glucose have all proved their efficiency, and telemedicine it is making good progress. The indirect costs of diabetes in Spain are much higher than the directones, showing the importance of inverting the paradox. The optimization of resources depends not only on the ability of the physicians, but also the administration, to implant and sustain technological innovations in our system, and with that make it effective in terms of benefits. Cost-effectiveness and cost-utility analysis are needed to prioritize and allow health management services to make the correct choices for approaching this prevalent chronic disease. PMID:25453400

  3. Nanofluidic crystal: a facile, high-efficiency and high-power-density scaling up scheme for energy harvesting based on nanofluidic reverse electrodialysis.

    PubMed

    Ouyang, Wei; Wang, Wei; Zhang, Haixia; Wu, Wengang; Li, Zhihong

    2013-08-30

    The great advances in nanotechnology call for advances in miniaturized power sources for micro/nano-scale systems. Nanofluidic channels have received great attention as promising high-power-density substitutes for ion exchange membranes for use in energy harvesting from ambient ionic concentration gradient, namely reverse electrodialysis. This paper proposes the nanofluidic crystal (NFC), of packed nanoparticles in micro-meter-sized confined space, as a facile, high-efficiency and high-power-density scaling-up scheme for energy harvesting by nanofluidic reverse electrodialysis (NRED). Obtained from the self-assembly of nanoparticles in a micropore, the NFC forms an ion-selective network with enormous nanochannels due to electrical double-layer overlap in the nanoparticle interstices. As a proof-of-concept demonstration, a maximum efficiency of 42.3 ± 1.84%, a maximum power density of 2.82 ± 0.22 W m(-2), and a maximum output power of 1.17 ± 0.09 nW/unit (nearly three orders of magnitude of amplification compared to other NREDs) were achieved in our prototype cell, which was prepared within 30 min. The current NFC-based prototype cell can be parallelized and cascaded to achieve the desired output power and open circuit voltage. This NFC-based scaling-up scheme for energy harvesting based on NRED is promising for the building of self-powered micro/nano-scale systems.

  4. Computationally efficient solution to the Cahn-Hilliard equation: Adaptive implicit time schemes, mesh sensitivity analysis and the 3D isoperimetric problem

    NASA Astrophysics Data System (ADS)

    Wodo, Olga; Ganapathysubramanian, Baskar

    2011-07-01

    We present an efficient numerical framework for analyzing spinodal decomposition described by the Cahn-Hilliard equation. We focus on the analysis of various implicit time schemes for two and three dimensional problems. We demonstrate that significant computational gains can be obtained by applying embedded, higher order Runge-Kutta methods in a time adaptive setting. This allows accessing time-scales that vary by five orders of magnitude. In addition, we also formulate a set of test problems that isolate each of the sub-processes involved in spinodal decomposition: interface creation and bulky phase coarsening. We analyze the error fluctuations using these test problems on the split form of the Cahn-Hilliard equation solved using the finite element method with basis functions of different orders. Any scheme that ensures at least four elements per interface satisfactorily captures both sub-processes. Our findings show that linear basis functions have superior error-to-cost properties. This strategy - coupled with a domain decomposition based parallel implementation - let us notably augment the efficiency of a numerical Cahn-Hillard solver, and open new venues for its practical applications, especially when three dimensional problems are considered. We use this framework to address the isoperimetric problem of identifying local solutions in the periodic cube in three dimensions. The framework is able to generate all five hypothesized candidates for the local solution of periodic isoperimetric problem in 3D - sphere, cylinder, lamella, doubly periodic surface with genus two (Lawson surface) and triply periodic minimal surface (P Schwarz surface).

  5. A Electronic Voting Scheme Achieved by Using Quantum Proxy Signature

    NASA Astrophysics Data System (ADS)

    Cao, Hai-Jing; Ding, Li-Yuan; Yu, Yao-Feng; Li, Peng-Fei

    2016-09-01

    In this paper, we propose a new electronic voting scheme using Bell entangled states as quantum channels. This scheme is based on quantum proxy signature. The voter Alice, vote management center Bob, teller Charlie and scrutineer Diana only perform single particle measurement to realize the electronic voting process. So the scheme reduces the technical difficulty and increases operation efficiency. It can be easily realized. We use quantum key distribution and one-time pad to guarantee its unconditional security. The scheme uses the physical characteristics of quantum mechanics to guarantee its anonymity, verifiability, unforgetability and undeniability.

  6. Transformations of Nitrogen from Secondary Treated Wastewater when Infiltrated in Managed Aquifer Recharge Schemes

    NASA Astrophysics Data System (ADS)

    Silver, Matthew; Wefer-Roehl, Annette; Kübeck, Christine; Schüth, Christoph

    2016-04-01

    The EU FP7 project MARSOL seeks to address water scarcity challenges in arid regions, where managed aquifer recharge (MAR) is an upcoming technology to recharge depleted aquifers using alternative water sources. Within this framework, we conduct column experiments to investigate transformations of nitrogen species when secondary treated wastewater (STWW) is infiltrated through two natural soils being considered for managed aquifer recharge. The soils vary considerably in organic matter content, with total organic matter determined by loss on ignition of 6.8 and 2.9 percent by mass for Soil 1 and Soil 2, respectively. Ammonium (NH4+) concentrations as high as 8.6 mg/L have been measured in pore water samples from Soil #1, indicating that ammonium could be a contaminant of concern in MAR applications using STWW, with consideration of the EU limit of 0.5 mg/L for NH4+. The two forms of nitrogen with the highest concentrations in the secondary treated wastewater are nitrate (NO3‑) and dissolved organic nitrogen (DON). In water samples taken from the soil columns, a mass balance of measured ions shows a deficit of nitrogen in ionic form in the upper to middle depths of the soil, suggesting the presence of unmeasured species. These are likely nitrous oxide or dinitrogen gas, which would signify that denitrification is occurring. Measurements of N2O from water samples will verify its presence and spatial variation. The ammonium concentrations increase slowly in the upper parts of the soil but then increase more sharply at greater depth, after NO3‑ is depleted, suggesting that DON is the source of the produced NH4+. The production of NH4+ is presumed to be facilitated microbiologically. It is hypothesized that at higher organic carbon to total nitrogen (C:N) ratios, more NH4+ will be formed. To test this, in the experiments with Soil #2, three different inflow waters are used, listed in order of decreasing C:N ratio: STWW, STWW with NO3‑ added to a concentration of

  7. Transformations of Nitrogen from Secondary Treated Wastewater when Infiltrated in Managed Aquifer Recharge Schemes

    NASA Astrophysics Data System (ADS)

    Silver, Matthew; Wefer-Roehl, Annette; Kübeck, Christine; Schüth, Christoph

    2016-04-01

    The EU FP7 project MARSOL seeks to address water scarcity challenges in arid regions, where managed aquifer recharge (MAR) is an upcoming technology to recharge depleted aquifers using alternative water sources. Within this framework, we conduct column experiments to investigate transformations of nitrogen species when secondary treated wastewater (STWW) is infiltrated through two natural soils being considered for managed aquifer recharge. The soils vary considerably in organic matter content, with total organic matter determined by loss on ignition of 6.8 and 2.9 percent by mass for Soil 1 and Soil 2, respectively. Ammonium (NH4+) concentrations as high as 8.6 mg/L have been measured in pore water samples from Soil #1, indicating that ammonium could be a contaminant of concern in MAR applications using STWW, with consideration of the EU limit of 0.5 mg/L for NH4+. The two forms of nitrogen with the highest concentrations in the secondary treated wastewater are nitrate (NO3-) and dissolved organic nitrogen (DON). In water samples taken from the soil columns, a mass balance of measured ions shows a deficit of nitrogen in ionic form in the upper to middle depths of the soil, suggesting the presence of unmeasured species. These are likely nitrous oxide or dinitrogen gas, which would signify that denitrification is occurring. Measurements of N2O from water samples will verify its presence and spatial variation. The ammonium concentrations increase slowly in the upper parts of the soil but then increase more sharply at greater depth, after NO3- is depleted, suggesting that DON is the source of the produced NH4+. The production of NH4+ is presumed to be facilitated microbiologically. It is hypothesized that at higher organic carbon to total nitrogen (C:N) ratios, more NH4+ will be formed. To test this, in the experiments with Soil #2, three different inflow waters are used, listed in order of decreasing C:N ratio: STWW, STWW with NO3- added to a concentration of 80 mg

  8. Sensor failure detection and management scheme for pressure probes using Kalman filtering technique

    NASA Astrophysics Data System (ADS)

    Kumar, N. Shantha

    1995-06-01

    For high performance, high angle of attack fighter aircraft, accurate and high fidelity airdata parameters are crucial for the flight control system. At high angle of attack, where small changes in angle of attack can greatly influence aerodynamic properties of the aircraft, the problem of flight control augmentation is extremely complicated. In this flight regime, it is critical that accurate measurements of airdata parameters including angle of attack, angle of sideslip and dynamic pressure are made available for use by the flight augmentation system. But at high angle of attack, it is difficult to measure airdata accurately using conventional intrusive sensing devices, because of upstream vortices and flow separation. To overcome this difficulty, a non-intrusive Flush Airdata Sensing system (FADS) has been developed. The FADS is a simple hardware item with the basic fixture being a hemispherical or conical cap mounted at the nose of the fuselage. A number of small holes are drilled around the cap in annular rings. The pressure at each hole is measured by pressure transducers and related to airdata parameters by a non-linear aerodynamic model derived from potential flow. A 7-hole pressure probe, proposed by the DLR for implementation on an advanced experimental fighter aircraft for airdata measurements at high angle of attack, has redundant measurements in angle of attack, angle of side slip and dynamic pressure to ensure control system augmentation at high angle of attack, in spite of some pressure sensor failure or malfunctioning. Such a system requires an algorithm which detects pressure sensor failure and performs fault management in real time. In this report, a concept for an algorithm using a recursive Kalman filtering technique has been proposed and developed. The algorithm is tested on a 5 hole pressure probe which is used in experimental flights of C-160 Transall aircraft.

  9. 75 FR 78231 - Management of Energy and Water Efficiency in Federal Buildings: Availability of Guidance

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-15

    ... of Energy Efficiency and Renewable Energy Management of Energy and Water Efficiency in Federal Buildings: Availability of Guidance AGENCY: Office of Energy Efficiency and Renewable Energy, Department of... Subsection (f), Use of Energy and Water Efficiency Measures in Federal Buildings) is available at:...

  10. Blood flow velocity estimation from x-ray densitometric data: an efficient numerical scheme for the inverse advection problem

    NASA Astrophysics Data System (ADS)

    Sarry, L.; Peng, Y. J.; Boire, J. Y.

    2002-01-01

    In previously published studies, blood flow velocity from x-ray biplane angiography was measured by solving an inverse advection problem, relating velocity to bolus densities summed across sections. Both spatial and temporal velocity variations were recovered through a computationally expensive parameter estimation algorithm. Here we prove the existence and uniqueness of the solution on three sub-domains of the plane defined by the axial position along the vessel and the time of the angiographic sequence. A fast direct scheme was designed in conjunction with a regularization step stemming from the volume flow conservation law applied on consecutive segments. Its accuracy and immunity towards noise were tested on both simulated and real densitometric data. The relative error between the estimated and expected velocities was less than 5% for more than 90% of the points of the spatiotemporal plane with simulated densities normalized to 1.0 and a Gaussian additive noise of standard deviation 0.01. For densities reconstructed from a biplane angiographic sequence, increase in velocity is used as a functional index for the stenosis ratio and to characterize the sharing of flow at bifurcation.

  11. A New Tool for Effective and Efficient Project Management

    SciTech Connect

    Willett, Jesse A

    2011-12-01

    Organizations routinely handle thousands of projects per year, and it is difficult to manage all these projects concurrently. Too often, projects do not get the attention they need when they need it. Management inattention can lead to late projects or projects with less than desirable content and/or deliverables. This paper discusses the application of Visual Project Management (VPM) as a method to track and manage projects. The VPM approach proved to be a powerful management tool without the overhead and restrictions of traditional management methods.

  12. A Memory-Efficient Deterministic Finite Automaton-Based Bit-Split String Matching Scheme Using Pattern Uniqueness in Deep Packet Inspection

    PubMed Central

    Kim, HyunJin; Choi, Kang-Il; Choi, Sang-Il

    2015-01-01

    This paper proposes a memory-efficient bit-split string matching scheme for deep packet inspection (DPI). When the number of target patterns becomes large, the memory requirements of the string matching engine become a critical issue. The proposed string matching scheme reduces the memory requirements using the uniqueness of the target patterns in the deterministic finite automaton (DFA)-based bit-split string matching. The pattern grouping extracts a set of unique patterns from the target patterns. In the set of unique patterns, a pattern is not the suffix of any other patterns. Therefore, in the DFA constructed with the set of unique patterns, when only one pattern can be matched in an output state. In the bit-split string matching, multiple finite-state machine (FSM) tiles with several input bit groups are adopted in order to reduce the number of stored state transitions. However, the memory requirements for storing the matching vectors can be large because each bit in the matching vector is used to identify whether its own pattern is matched or not. In our research, the proposed pattern grouping is applied to the multiple FSM tiles in the bit-split string matching. For the set of unique patterns, the memory-based bit-split string matching engine stores only the pattern match index for each state to indicate the match with its own unique pattern. Therefore, the memory requirements are significantly decreased by not storing the matching vectors in the string matchers for the set of unique patterns. The experimental results show that the proposed string matching scheme can reduce the storage cost significantly compared to the previous bit-split string matching methods. PMID:25938779

  13. A memory-efficient deterministic finite automaton-based bit-split string matching scheme using pattern uniqueness in deep packet inspection.

    PubMed

    Kim, HyunJin; Choi, Kang-Il; Choi, Sang-Il

    2015-01-01

    This paper proposes a memory-efficient bit-split string matching scheme for deep packet inspection (DPI). When the number of target patterns becomes large, the memory requirements of the string matching engine become a critical issue. The proposed string matching scheme reduces the memory requirements using the uniqueness of the target patterns in the deterministic finite automaton (DFA)-based bit-split string matching. The pattern grouping extracts a set of unique patterns from the target patterns. In the set of unique patterns, a pattern is not the suffix of any other patterns. Therefore, in the DFA constructed with the set of unique patterns, when only one pattern can be matched in an output state. In the bit-split string matching, multiple finite-state machine (FSM) tiles with several input bit groups are adopted in order to reduce the number of stored state transitions. However, the memory requirements for storing the matching vectors can be large because each bit in the matching vector is used to identify whether its own pattern is matched or not. In our research, the proposed pattern grouping is applied to the multiple FSM tiles in the bit-split string matching. For the set of unique patterns, the memory-based bit-split string matching engine stores only the pattern match index for each state to indicate the match with its own unique pattern. Therefore, the memory requirements are significantly decreased by not storing the matching vectors in the string matchers for the set of unique patterns. The experimental results show that the proposed string matching scheme can reduce the storage cost significantly compared to the previous bit-split string matching methods.

  14. Efficient and Secure Self-Organized Public Key Management for Mobile Ad Hoc Networks

    NASA Astrophysics Data System (ADS)

    Choi, Daeseon; Lee, Younho; Park, Yongsu; Jin, Seung-Hun; Yoon, Hyunsoo

    This paper presents a fully self-organized key management scheme for mobile ad hoc networks. Unlike most previous schemes, there is no priori shared secret or no priori trust relationship in the proposed scheme; every node plays the same role and carries out the same function of key management. The proposed scheme consists of (1) Handshaking (HS) and (2) Certificate request/reply (CRR) procedures. In HS, a node acquires the public key of the approaching node via a secure side channel. In CRR, a node requests certificates of a remote node via a radio channel to the nodes that it has HSed. If the number of received valid certificates that contain the same public key exceeds a given threshold, the node accepts the remote node's public key as valid. Security is rigorously analyzed against various known attacks and network costs are intensively analyzed mathematically. Using this analysis, we provide parameter selection guideline to optimize performance and to maintain security for diverse cases. Simulation results show that every node acquires the public keys of all other nodes at least 5 times faster than in a previous scheme.

  15. Knowledge management for efficient quantitative analyses during regulatory reviews.

    PubMed

    Krudys, Kevin; Li, Fang; Florian, Jeffry; Tornoe, Christoffer; Chen, Ying; Bhattaram, Atul; Jadhav, Pravin; Neal, Lauren; Wang, Yaning; Gobburu, Joga; Lee, Peter I D

    2011-11-01

    Knowledge management comprises the strategies and methods employed to generate and leverage knowledge within an organization. This report outlines the activities within the Division of Pharmacometrics at the US FDA to effectively manage knowledge with the ultimate goal of improving drug development and advancing public health. The infrastructure required for pharmacometric knowledge management includes provisions for data standards, queryable databases, libraries of modeling tools, archiving of analysis results and reporting templates for effective communication. Two examples of knowledge management systems developed within the Division of Pharmacometrics are used to illustrate these principles. The benefits of sound knowledge management include increased productivity, allowing reviewers to focus on research questions spanning new drug applications, such as improved trial design and biomarker development. The future of knowledge management depends on the collaboration between the FDA and industry to implement data and model standards to enhance sharing and dissemination of knowledge.

  16. Knowledge management for efficient quantitative analyses during regulatory reviews.

    PubMed

    Krudys, Kevin; Li, Fang; Florian, Jeffry; Tornoe, Christoffer; Chen, Ying; Bhattaram, Atul; Jadhav, Pravin; Neal, Lauren; Wang, Yaning; Gobburu, Joga; Lee, Peter I D

    2011-11-01

    Knowledge management comprises the strategies and methods employed to generate and leverage knowledge within an organization. This report outlines the activities within the Division of Pharmacometrics at the US FDA to effectively manage knowledge with the ultimate goal of improving drug development and advancing public health. The infrastructure required for pharmacometric knowledge management includes provisions for data standards, queryable databases, libraries of modeling tools, archiving of analysis results and reporting templates for effective communication. Two examples of knowledge management systems developed within the Division of Pharmacometrics are used to illustrate these principles. The benefits of sound knowledge management include increased productivity, allowing reviewers to focus on research questions spanning new drug applications, such as improved trial design and biomarker development. The future of knowledge management depends on the collaboration between the FDA and industry to implement data and model standards to enhance sharing and dissemination of knowledge. PMID:22111855

  17. Single Cell Proteolytic Assays to Investigate Cancer Clonal Heterogeneity and Cell Dynamics Using an Efficient Cell Loading Scheme

    NASA Astrophysics Data System (ADS)

    Chen, Yu-Chih; Cheng, Yu-Heng; Ingram, Patrick; Yoon, Euisik

    2016-06-01

    Proteolytic degradation of the extracellular matrix (ECM) is critical in cancer invasion, and recent work suggests that heterogeneous cancer populations cooperate in this process. Despite the importance of cell heterogeneity, conventional proteolytic assays measure average activity, requiring thousands of cells and providing limited information about heterogeneity and dynamics. Here, we developed a microfluidic platform that provides high-efficiency cell loading and simple valveless isolation, so the proteolytic activity of a small sample (10–100 cells) can be easily characterized. Combined with a single cell derived (clonal) sphere formation platform, we have successfully demonstrated the importance of microenvironmental cues for proteolytic activity and also investigated the difference between clones. Furthermore, the platform allows monitoring single cells at multiple time points, unveiling different cancer cell line dynamics in proteolytic activity. The presented tool facilitates single cell proteolytic analysis using small samples, and our findings illuminate the heterogeneous and dynamic nature of proteolytic activity.

  18. Single Cell Proteolytic Assays to Investigate Cancer Clonal Heterogeneity and Cell Dynamics Using an Efficient Cell Loading Scheme

    PubMed Central

    Chen, Yu-Chih; Cheng, Yu-Heng; Ingram, Patrick; Yoon, Euisik

    2016-01-01

    Proteolytic degradation of the extracellular matrix (ECM) is critical in cancer invasion, and recent work suggests that heterogeneous cancer populations cooperate in this process. Despite the importance of cell heterogeneity, conventional proteolytic assays measure average activity, requiring thousands of cells and providing limited information about heterogeneity and dynamics. Here, we developed a microfluidic platform that provides high-efficiency cell loading and simple valveless isolation, so the proteolytic activity of a small sample (10–100 cells) can be easily characterized. Combined with a single cell derived (clonal) sphere formation platform, we have successfully demonstrated the importance of microenvironmental cues for proteolytic activity and also investigated the difference between clones. Furthermore, the platform allows monitoring single cells at multiple time points, unveiling different cancer cell line dynamics in proteolytic activity. The presented tool facilitates single cell proteolytic analysis using small samples, and our findings illuminate the heterogeneous and dynamic nature of proteolytic activity. PMID:27283981

  19. The effect of air flow on the temperature distribution and the harmonic conversion efficiency of the ADP crystal with large aperture in the temperature control scheme

    NASA Astrophysics Data System (ADS)

    Sun, Fuzhong; Zhang, Peng; Lu, Lihua; Xiang, Yong; Bai, Qingshun

    2016-03-01

    This paper presented a temperature control scheme for ammonium dihydrogen phosphate (ADP) crystal of V80 mm in diameter, and the influence of the air flow was also studied. This research aims to obtain the high energy, high frequency laser with large aperture under the non-critical phase matching (NCPM). Firstly, thermal analysis was carried out to investigate the air flow property in the cavity, as well as the effect of ambient temperature was analyzed. Secondly, the temperature distributions of air flow were achieved using the Finite Volume Method (FVM), and this prediction was validated by the experiment results. Finally, the effect of air flow in the cavity was obtained from the heating method, and the variation of harmonic conversion efficiency caused by the ambient temperature was also highlighted.

  20. HVAC & Building Management Control System Energy Efficiency Replacements

    SciTech Connect

    Hernandez, Adriana

    2012-09-21

    The project objective was the replacement of an aging, un-repairable HVAC system which has grown inefficient and a huge energy consumer with low energy and efficient HVAC units, and installation of energy efficient building control technologies at City's YMCA Community Center.

  1. Make safety programs work efficiently with an effective management plan

    SciTech Connect

    Lyle, D.

    1995-07-01

    Like budgets or any other major projects, safety works better when everyone in the company commits to manage the program effectively. Let someone overspend a budget or miss a projected revenue plan and a company moves quickly to correct the problem. However, there is a tendency to ignore a manager whose department has a poor safety record, as though it`s bad luck.

  2. Relaxation schemes for Chebyshev spectral multigrid methods

    NASA Technical Reports Server (NTRS)

    Kang, Yimin; Fulton, Scott R.

    1993-01-01

    Two relaxation schemes for Chebyshev spectral multigrid methods are presented for elliptic equations with Dirichlet boundary conditions. The first scheme is a pointwise-preconditioned Richardson relaxation scheme and the second is a line relaxation scheme. The line relaxation scheme provides an efficient and relatively simple approach for solving two-dimensional spectral equations. Numerical examples and comparisons with other methods are given.

  3. A comparative signaling cost analysis of Macro Mobility scheme in NEMO (MM-NEMO) with mobility management protocol

    NASA Astrophysics Data System (ADS)

    Islam, Shayla; Abdalla, Aisha H.; Habaebi, Mohamed H.; Latif, Suhaimi A.; Hassan, Wan H.; Hasan, Mohammad K.; Ramli, H. A. M.; Khalifa, Othman O.

    2013-12-01

    NEMO BSP is an upgraded addition to Mobile IPv6 (MIPv6). As MIPv6 and its enhancements (i.e. HMIPv6) possess some limitations like higher handoff latency, packet loss, NEMO BSP also faces all these shortcomings by inheritance. Network Mobility (NEMO) is involved to handle the movement of Mobile Router (MR) and it's Mobile Network Nodes (MNNs) during handoff. Hence it is essential to upgrade the performance of mobility management protocol to obtain continuous session connectivity with lower delay and packet loss in NEMO environment. The completion of handoff process in NEMO BSP usually takes longer period since MR needs to register its single primary care of address (CoA) with home network that may cause performance degradation of the applications running on Mobile Network Nodes. Moreover, when a change in point of attachment of the mobile network is accompanied by a sudden burst of signaling messages, "Signaling Storm" occurs which eventually results in temporary congestion, packet delays or even packet loss. This effect is particularly significant for wireless environment where a wireless link is not as steady as a wired link since bandwidth is relatively limited in wireless link. Hence, providing continuous Internet connection without any interruption through applying multihoming technique and route optimization mechanism in NEMO are becoming the center of attention to the current researchers. In this paper, we propose a handoff cost model to compare the signaling cost of MM-NEMO with NEMO Basic Support Protocol (NEMO BSP) and HMIPv6.The numerical results shows that the signaling cost for the MM-NEMO scheme is about 69.6 % less than the NEMO-BSP and HMIPv6.

  4. Efficient Assessment of the Environment for Integral Urban Water Management

    NASA Astrophysics Data System (ADS)

    Rost, Grit; Londong, Jörg

    2015-04-01

    Introduction: Sustainable water supply and sanitation is fundamental, especially in countries that are also particularly vulnerable to water-related problems. The Integrated Water Resources Management (IWRM) approach makes sure that water management is organised in a transdisciplinary way taking into account the river basin, the hydrologic system and the appendant organisation like culture, law and economics. The main objective of IWRM is the sustainable organisation of water resources quality and quantity (GWP and INBO 2009). However there are more important targets in sustainable use of water resources. New sanitation systems are focussing on adding value and maintaining essential resources in circular flow. Focussing on material fluxes can contribute on water quality, food security, sustainable use of renewable energy, adaption on water scarcity and also on rising water and sanitation demand because of rapid urban and suburban growth (Price and Vojinović 2011; Rost et al 2013; Stäudel et al 2014). Problem: There are several planning tools for IWRM as well as for urban water management. But to complete the IWRM approach for the resource oriented concept a systematic assessment tool is missing. The assessment of crucial indicators obviously requires a lot of data from different subjects/disciplines, in different scales of detail and in different accuracy and in data acquisition (Karthe et al 2014). On the one hand there will be data abundance and on the other hand the data can be unavailable or unfeasible for example because of scale and specification(Rost et al 2013). Such a complex integrated concept requires a clearly worked out structure for the way of managing and priority setting. Purpose: To get systematic in the complex planning process the toolbox model is going to develop. The assessment of the environmental screening (one part of the toolbox) is going to be presented in this paper. The first step of assessment leans on the assertion that each of the

  5. Indicators of waste management efficiency related to different territorial conditions

    SciTech Connect

    Passarini, Fabrizio; Vassura, Ivano; Monti, Francesco; Morselli, Luciano; Villani, Barbara

    2011-04-15

    The amount of waste produced and the control of separate collection are crucial issues for the planning of a territorial Integrated Waste Management System, enabling the allocation of each sorted waste fraction to the proper treatment and recycling processes. The present study focuses on assessing indicators of different waste management systems in areas characterized by different territorial conditions. The investigated case study concerns the municipalities of Emilia Romagna (northern Italy), which present a rather uniform socioeconomic situation, but a variety of geographic, urban and waste management characteristics. A survey of waste generation and collection rates was carried out, and correlated with the different territorial conditions, classifying the municipalities according to altitude and population density. The best environmental performances, in terms of high separate collection rate, were found on average in rural areas in the plain, while the lowest waste generation was associated with rural hill towns.

  6. Efficient Management of Fruit Pests by Pheromone Nanogels

    PubMed Central

    Bhagat, Deepa; Samanta, Suman K.; Bhattacharya, Santanu

    2013-01-01

    Environment-friendly management of fruit flies involving pheromones is useful in reducing the undesirable pest populations responsible for decreasing the yield and the crop quality. A nanogel has been prepared from a pheromone, methyl eugenol (ME) using a low-molecular mass gelator. This was very stable at open ambient conditions and slowed down the evaporation of pheromone significantly. This enabled its easy handling and transportation without refrigeration, and reduction in the frequency of pheromone recharging in the orchard. Notably the involvement of the nano-gelled pheromone brought about an effective management of Bactrocera dorsalis, a prevalent harmful pest for a number of fruits including guava. Thus a simple, practical and low cost green chemical approach is developed that has a significant potential for crop protection, long lasting residual activity, excellent efficacy and favorable safety profiles. This makes the present invention well-suited for pest management in a variety of crops. PMID:23416455

  7. Efficient management of fruit pests by pheromone nanogels.

    PubMed

    Bhagat, Deepa; Samanta, Suman K; Bhattacharya, Santanu

    2013-01-01

    Environment-friendly management of fruit flies involving pheromones is useful in reducing the undesirable pest populations responsible for decreasing the yield and the crop quality. A nanogel has been prepared from a pheromone, methyl eugenol (ME) using a low-molecular mass gelator. This was very stable at open ambient conditions and slowed down the evaporation of pheromone significantly. This enabled its easy handling and transportation without refrigeration, and reduction in the frequency of pheromone recharging in the orchard. Notably the involvement of the nano-gelled pheromone brought about an effective management of Bactrocera dorsalis, a prevalent harmful pest for a number of fruits including guava. Thus a simple, practical and low cost green chemical approach is developed that has a significant potential for crop protection, long lasting residual activity, excellent efficacy and favorable safety profiles. This makes the present invention well-suited for pest management in a variety of crops. PMID:23416455

  8. An Efficient, Semi-implicit Pressure-based Scheme Employing a High-resolution Finitie Element Method for Simulating Transient and Steady, Inviscid and Viscous, Compressible Flows on Unstructured Grids

    SciTech Connect

    Richard C. Martineau; Ray A. Berry

    2003-04-01

    equation in the PCICE-FEM scheme is provided with sufficient internal energy information to avoid iteration. The ability of the PCICE-FEM scheme to accurately and efficiently simulate a wide variety of inviscid and viscous compressible flows is demonstrated here.

  9. Efficient algorithms for optimal arrival scheduling and air traffic flow management

    NASA Astrophysics Data System (ADS)

    Saraf, Aditya

    The research presented in this dissertation is motivated by the need for new, efficient algorithms for the solution of two important problems currently faced by the air-traffic control community: (i) optimal scheduling of aircraft arrivals at congested airports, and (ii) optimal National Airspace System (NAS) wide traffic flow management. In the first part of this dissertation, we present an optimal airport arrival scheduling algorithm, which works within a hierarchical scheduling structure. This structure consists of schedulers at multiple points along the arrival-route. Schedulers are linked through acceptance-rate constraints, which are passed up from downstream metering-points. The innovation in this scheduling algorithm is that these constraints are computed by using an Eulerian model-based optimization scheme. This rate computation removes inefficiencies introduced in the schedule through ad hoc acceptance-rate computations. The scheduling process at every metering-point uses its optimal acceptance-rate as a constraint and computes optimal arrival sequences by using a combinatorial search-algorithm. We test this algorithm in a dynamic air-traffic environment, which can be customized to emulate different arrival scenarios. In the second part of this dissertation, we introduce a novel two-level control system for optimal traffic-flow management. The outer-level control module of this two-level control system generates an Eulerian-model of the NAS by aggregating aircraft into interconnected control-volumes. Using this Eulerian model of the airspace, control strategies like Model Predictive Control are applied to find the optimal inflow and outflow commands for each control-volume so that efficient flows are achieved in the NAS. Each control-volume has its separate inner-level control-module. The inner-level control-module takes in the optimal inflow and outflow commands generated by the outer control-module as reference inputs and uses hybrid aircraft models to

  10. Integrated energy management study. Energy efficient transport program

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The Integrated Energy Management (IEM) Study investigated the practicality and feasibility of a closed-loop energy management system for transport aircraft. The study involved: (1) instrumentation and collection of in-flight data for a United Airlines 727-200 flying 80 revenue flights throughout the United Airlines network,(2) analysis of the in-flight data to select representative city pairs and establish operational procedures employed in flying a reference flight profile, (3) simulation of the reference profile in a fast-time model to verify the model and establish performance values against which to measure IEM benefits, (4) development of IEM algorithms, and (5) assessment of the IEM concept.

  11. Managing carbon emissions in China through building energy efficiency.

    PubMed

    Li, Jun; Colombier, Michel

    2009-06-01

    This paper attempts to analyse the role of building energy efficiency (BEE) in China in addressing climate change mitigation. It provides an analysis of the current situation and future prospects for the adoption of BEE technologies in Chinese cities. It outlines the economic and institutional barriers to large-scale deployment of the sustainable, low-carbon, and even carbon-free construction techniques. Based on a comprehensive overview of energy demand characteristics and development trends driven by economic and demographic growth, different policy tools for cost-effective CO(2) emission reduction in the Chinese construction sector are described. We propose a comprehensive approach combining building design and construction, and the urban planning and building material industries, in order to drastically improve BEE during this period of rapid urban development. A coherent institutional framework needs to be established to ensure the implementation of efficiency policies. Regulatory and incentive options should be integrated into the policy portfolios of BEE to minimise the efficiency gap and to realise sizeable carbon emissions cuts in the next decades. We analyse in detail several policies and instruments, and formulate relevant policy proposals fostering low-carbon construction technology in China. Specifically, Our analysis shows that improving building energy efficiency can generate considerable carbon emissions reduction credits with competitive price under the CDM framework.

  12. Managing carbon emissions in China through building energy efficiency.

    PubMed

    Li, Jun; Colombier, Michel

    2009-06-01

    This paper attempts to analyse the role of building energy efficiency (BEE) in China in addressing climate change mitigation. It provides an analysis of the current situation and future prospects for the adoption of BEE technologies in Chinese cities. It outlines the economic and institutional barriers to large-scale deployment of the sustainable, low-carbon, and even carbon-free construction techniques. Based on a comprehensive overview of energy demand characteristics and development trends driven by economic and demographic growth, different policy tools for cost-effective CO(2) emission reduction in the Chinese construction sector are described. We propose a comprehensive approach combining building design and construction, and the urban planning and building material industries, in order to drastically improve BEE during this period of rapid urban development. A coherent institutional framework needs to be established to ensure the implementation of efficiency policies. Regulatory and incentive options should be integrated into the policy portfolios of BEE to minimise the efficiency gap and to realise sizeable carbon emissions cuts in the next decades. We analyse in detail several policies and instruments, and formulate relevant policy proposals fostering low-carbon construction technology in China. Specifically, Our analysis shows that improving building energy efficiency can generate considerable carbon emissions reduction credits with competitive price under the CDM framework. PMID:19344996

  13. Institutional Values of Managed Mental Health Care: Efficiency or Oppression?

    ERIC Educational Resources Information Center

    Wilcoxon, S. Allen; Magnuson, Sandy; Norem, Ken

    2008-01-01

    The authors suggest that many managed mental health care (MMHC) practices have oppressive effects on members of cultural and ethnic minority groups. They examine the dissonance between institutional practices and cultural traditions that reflect insensitivity and forced conformity, particularly regarding time, pace, and intervention uniformity as…

  14. Efficiency Mode of Energy Management based on Optimal Flight Path

    NASA Astrophysics Data System (ADS)

    Yang, Ling-xiao

    2016-07-01

    One new method of searching the optimal flight path in target function is put forward, which is applied to energy section for reentry flight vehicle, and the optimal flight path in which the energy is managed to decline rapidly, is settled by this design. The research for energy management is meaningful for engineering, it can also improve the applicability and flexibility for vehicle. The angle-of-attack and the bank angle are used to regulate energy and range at unpowered reentry flight as control variables. Firstly, the angle-of-attack section for minimum lift-to-drag ratio is ensured by the relation of range and lift-to-drag ratio. Secondly, build the secure boundary for flight corridor by restrictions in flight. Thirdly, the D-e section is optimized for energy expending in corridor by the influencing rule of the D-e section and range. Finally, compare this design method with the traditional Pseudo-spectral method. Moreover, energy-managing is achieved by cooperating lateral motion, and the optimized D-e section is tracked to prove the practicability of programming flight path with energy management.

  15. A PWM Buck Converter With Load-Adaptive Power Transistor Scaling Scheme Using Analog-Digital Hybrid Control for High Energy Efficiency in Implantable Biomedical Systems.

    PubMed

    Park, Sung-Yun; Cho, Jihyun; Lee, Kyuseok; Yoon, Euisik

    2015-12-01

    We report a pulse width modulation (PWM) buck converter that is able to achieve a power conversion efficiency (PCE) of > 80% in light loads 100 μA) for implantable biomedical systems. In order to achieve a high PCE for the given light loads, the buck converter adaptively reconfigures the size of power PMOS and NMOS transistors and their gate drivers in accordance with load currents, while operating at a fixed frequency of 1 MHz. The buck converter employs the analog-digital hybrid control scheme for coarse/fine adjustment of power transistors. The coarse digital control generates an approximate duty cycle necessary for driving a given load and selects an appropriate width of power transistors to minimize redundant power dissipation. The fine analog control provides the final tuning of the duty cycle to compensate for the error from the coarse digital control. The mode switching between the analog and digital controls is accomplished by a mode arbiter which estimates the average of duty cycles for the given load condition from limit cycle oscillations (LCO) induced by coarse adjustment. The fabricated buck converter achieved a peak efficiency of 86.3% at 1.4 mA and > 80% efficiency for a wide range of load conditions from 45 μA to 4.1 mA, while generating 1 V output from 2.5-3.3 V supply. The converter occupies 0.375 mm(2) in 0.18 μm CMOS processes and requires two external components: 1.2 μF capacitor and 6.8 μH inductor.

  16. A PWM Buck Converter With Load-Adaptive Power Transistor Scaling Scheme Using Analog-Digital Hybrid Control for High Energy Efficiency in Implantable Biomedical Systems.

    PubMed

    Park, Sung-Yun; Cho, Jihyun; Lee, Kyuseok; Yoon, Euisik

    2015-12-01

    We report a pulse width modulation (PWM) buck converter that is able to achieve a power conversion efficiency (PCE) of > 80% in light loads 100 μA) for implantable biomedical systems. In order to achieve a high PCE for the given light loads, the buck converter adaptively reconfigures the size of power PMOS and NMOS transistors and their gate drivers in accordance with load currents, while operating at a fixed frequency of 1 MHz. The buck converter employs the analog-digital hybrid control scheme for coarse/fine adjustment of power transistors. The coarse digital control generates an approximate duty cycle necessary for driving a given load and selects an appropriate width of power transistors to minimize redundant power dissipation. The fine analog control provides the final tuning of the duty cycle to compensate for the error from the coarse digital control. The mode switching between the analog and digital controls is accomplished by a mode arbiter which estimates the average of duty cycles for the given load condition from limit cycle oscillations (LCO) induced by coarse adjustment. The fabricated buck converter achieved a peak efficiency of 86.3% at 1.4 mA and > 80% efficiency for a wide range of load conditions from 45 μA to 4.1 mA, while generating 1 V output from 2.5-3.3 V supply. The converter occupies 0.375 mm(2) in 0.18 μm CMOS processes and requires two external components: 1.2 μF capacitor and 6.8 μH inductor. PMID:26742139

  17. Energy conservation and management system using efficient building automation

    NASA Astrophysics Data System (ADS)

    Ahmed, S. Faiz; Hazry, D.; Tanveer, M. Hassan; Joyo, M. Kamran; Warsi, Faizan A.; Kamarudin, H.; Wan, Khairunizam; Razlan, Zuradzman M.; Shahriman A., B.; Hussain, A. T.

    2015-05-01

    In countries where the demand and supply gap of electricity is huge and the people are forced to endure increasing hours of load shedding, unnecessary consumption of electricity makes matters even worse. So the importance and need for electricity conservation increases exponentially. This paper outlines a step towards the conservation of energy in general and electricity in particular by employing efficient Building Automation technique. It should be noted that by careful designing and implementation of the Building Automation System, up to 30% to 40% of energy consumption can be reduced, which makes a huge difference for energy saving. In this study above mentioned concept is verified by performing experiment on a prototype experimental room and by implementing efficient building automation technique. For the sake of this efficient automation, Programmable Logic Controller (PLC) is employed as a main controller, monitoring various system parameters and controlling appliances as per required. The hardware test run and experimental findings further clarifies and proved the concept. The added advantage of this project is that it can be implemented to both small and medium level domestic homes thus greatly reducing the overall unnecessary load on the Utility provider.

  18. Efficient identity management and access control in cloud environment

    NASA Astrophysics Data System (ADS)

    Gloster, Jonathan

    2013-05-01

    As more enterprises are enticed to move data to a cloud environment to enhance data sharing and reduce operating costs by exploiting shared resources, concerns have risen over the ability to secure information within the cloud. This paper examines how a traditional Identity and Access Control (IDAM) architecture can be adapted to address security concerns of a cloud environment. We propose changing the paradigm of IDAM form a pure trust model to a risk based model will enable information to be protected securely in a cloud environment without impacting efficiencies of cloud environments.

  19. Pareto Efficient Policy for Supervisory Power Management Control

    SciTech Connect

    Malikopoulos, Andreas

    2015-01-01

    n this paper we address the problem of online optimization of the supervisory power management control in parallel hybrid electric vehicles (HEVs). We model HEV opera- tion as a controlled Markov chain using the long-run expected average cost per unit time criterion, and we show that the control policy yielding the Pareto optimal solution minimizes the average cost criterion online. The effectiveness of the proposed solution is validated through simulation and compared to the solution derived with dynamic programming using the average cost criterion.

  20. Diamond/aluminium nitride composites for efficient thermal management applications

    SciTech Connect

    Cervenka, J.; Dontschuk, N.; Prawer, S.; Ladouceur, F.; Duvall, S. G.

    2012-07-30

    Synthetic diamond/AlN composite materials have been fabricated by a combination of microwave plasma-assisted chemical vapor deposition and molecular beam epitaxy. These wide band gap semiconductor heterojunctions show promises for many applications, including thermal management, deep ultraviolet light emitting devices, and high power and high temperature electronics. Here, we report results of an interface study of polycrystalline diamond layers grown on single crystal AlN(0001). High resolution transmission microscopy revealed atomically sharp interfaces between diamond and AlN. Temperature dependent Raman spectroscopy measurements showed reduced thermal resistance on diamond-coated AlN substrates compared to uncoated AlN at temperatures above 330 K.

  1. Waste management: how reducing partiality can promote efficient resource allocation.

    PubMed

    Choshen-Hillel, Shoham; Shaw, Alex; Caruso, Eugene M

    2015-08-01

    Two central principles that guide resource-allocation decisions are equity (providing equal pay for equal work) and efficiency (not wasting resources). When these two principles conflict with one another, people will often waste resources to avoid inequity. We suggest that people wish to avoid inequity not because they find it inherently unfair, but because they want to avoid the appearance of partiality associated with it. We explore one way to reduce waste by reducing the perceived partiality of inequitable allocations. Specifically, we hypothesize that people will be more likely to favor an efficient (albeit inequitable) allocation if it puts them in a disadvantaged position than if it puts others in a disadvantaged position. To test this hypothesis, we asked participants to choose between giving some extra resource to one person (thereby creating inequity between this person and equally deserving others) and not giving the resource to anyone (thereby wasting the resource). Six studies, using realistic scenarios and behavioral paradigms, provide robust evidence for a self-disadvantaging effect: Allocators were consistently more likely to create inequity to avoid wasting resources when the resulting inequity would put them at a relative disadvantage than when it would put others at a relative disadvantage. We further find that this self-disadvantaging effect is a direct result of people's concern about appearing partial. Our findings suggest the importance of impartiality even in distributive justice, thereby bridging a gap between the distributive and procedural justice literatures.

  2. Efficient management of multi-version clinical guidelines.

    PubMed

    Grandi, Fabio; Mandreoli, Federica; Martoglia, Riccardo

    2012-12-01

    Clinical medicine and health-care developments in recent years testified a tremendous increase in the number of available guidelines, i.e., "best practices" encoding and standardizing care procedures for a given disease. Clinical guidelines are subject to continuous development and revision by committees of expert physicians and health authorities and, thus, multiple versions coexist as a consequence of the clinical and healthcare activities. Moreover, several alternatives are usually included in order to make the guidelines as general as possible, making them difficult to handle both in manual and automated fashions. In this work, we will introduce techniques to model and to provide efficient personalized access to very large collections of multi-version clinical guidelines, which can be stored both in textual and in executable format in an XML repository. In this way, multiple temporal perspectives, patient profile and context information can be used by an automated personalization service to efficiently build on demand a guideline version tailored to a specific use case. PMID:22890019

  3. Nanoinformatics knowledge infrastructures: bringing efficient information management to nanomedical research

    NASA Astrophysics Data System (ADS)

    de la Iglesia, D.; Cachau, R. E.; García-Remesal, M.; Maojo, V.

    2013-01-01

    Nanotechnology represents an area of particular promise and significant opportunity across multiple scientific disciplines. Ongoing nanotechnology research ranges from the characterization of nanoparticles and nanomaterials to the analysis and processing of experimental data seeking correlations between nanoparticles and their functionalities and side effects. Due to their special properties, nanoparticles are suitable for cellular-level diagnostics and therapy, offering numerous applications in medicine, e.g. development of biomedical devices, tissue repair, drug delivery systems and biosensors. In nanomedicine, recent studies are producing large amounts of structural and property data, highlighting the role for computational approaches in information management. While in vitro and in vivo assays are expensive, the cost of computing is falling. Furthermore, improvements in the accuracy of computational methods (e.g. data mining, knowledge discovery, modeling and simulation) have enabled effective tools to automate the extraction, management and storage of these vast data volumes. Since this information is widely distributed, one major issue is how to locate and access data where it resides (which also poses data-sharing limitations). The novel discipline of nanoinformatics addresses the information challenges related to nanotechnology research. In this paper, we summarize the needs and challenges in the field and present an overview of extant initiatives and efforts.

  4. Nanoinformatics knowledge infrastructures: bringing efficient information management to nanomedical research.

    PubMed

    de la Iglesia, D; Cachau, R E; García-Remesal, M; Maojo, V

    2013-11-27

    Nanotechnology represents an area of particular promise and significant opportunity across multiple scientific disciplines. Ongoing nanotechnology research ranges from the characterization of nanoparticles and nanomaterials to the analysis and processing of experimental data seeking correlations between nanoparticles and their functionalities and side effects. Due to their special properties, nanoparticles are suitable for cellular-level diagnostics and therapy, offering numerous applications in medicine, e.g. development of biomedical devices, tissue repair, drug delivery systems and biosensors. In nanomedicine, recent studies are producing large amounts of structural and property data, highlighting the role for computational approaches in information management. While in vitro and in vivo assays are expensive, the cost of computing is falling. Furthermore, improvements in the accuracy of computational methods (e.g. data mining, knowledge discovery, modeling and simulation) have enabled effective tools to automate the extraction, management and storage of these vast data volumes. Since this information is widely distributed, one major issue is how to locate and access data where it resides (which also poses data-sharing limitations). The novel discipline of nanoinformatics addresses the information challenges related to nanotechnology research. In this paper, we summarize the needs and challenges in the field and present an overview of extant initiatives and efforts.

  5. Nanoinformatics knowledge infrastructures: bringing efficient information management to nanomedical research.

    PubMed

    de la Iglesia, D; Cachau, R E; García-Remesal, M; Maojo, V

    2013-11-27

    Nanotechnology represents an area of particular promise and significant opportunity across multiple scientific disciplines. Ongoing nanotechnology research ranges from the characterization of nanoparticles and nanomaterials to the analysis and processing of experimental data seeking correlations between nanoparticles and their functionalities and side effects. Due to their special properties, nanoparticles are suitable for cellular-level diagnostics and therapy, offering numerous applications in medicine, e.g. development of biomedical devices, tissue repair, drug delivery systems and biosensors. In nanomedicine, recent studies are producing large amounts of structural and property data, highlighting the role for computational approaches in information management. While in vitro and in vivo assays are expensive, the cost of computing is falling. Furthermore, improvements in the accuracy of computational methods (e.g. data mining, knowledge discovery, modeling and simulation) have enabled effective tools to automate the extraction, management and storage of these vast data volumes. Since this information is widely distributed, one major issue is how to locate and access data where it resides (which also poses data-sharing limitations). The novel discipline of nanoinformatics addresses the information challenges related to nanotechnology research. In this paper, we summarize the needs and challenges in the field and present an overview of extant initiatives and efforts. PMID:24932210

  6. Nanoinformatics knowledge infrastructures: bringing efficient information management to nanomedical research

    PubMed Central

    de la Iglesia, D; Cachau, R E; García-Remesal, M; Maojo, V

    2014-01-01

    Nanotechnology represents an area of particular promise and significant opportunity across multiple scientific disciplines. Ongoing nanotechnology research ranges from the characterization of nanoparticles and nanomaterials to the analysis and processing of experimental data seeking correlations between nanoparticles and their functionalities and side effects. Due to their special properties, nanoparticles are suitable for cellular-level diagnostics and therapy, offering numerous applications in medicine, e.g. development of biomedical devices, tissue repair, drug delivery systems and biosensors. In nanomedicine, recent studies are producing large amounts of structural and property data, highlighting the role for computational approaches in information management. While in vitro and in vivo assays are expensive, the cost of computing is falling. Furthermore, improvements in the accuracy of computational methods (e.g. data mining, knowledge discovery, modeling and simulation) have enabled effective tools to automate the extraction, management and storage of these vast data volumes. Since this information is widely distributed, one major issue is how to locate and access data where it resides (which also poses data-sharing limitations). The novel discipline of nanoinformatics addresses the information challenges related to nanotechnology research. In this paper, we summarize the needs and challenges in the field and present an overview of extant initiatives and efforts. PMID:24932210

  7. Towards Efficient Scientific Data Management Using Cloud Storage

    NASA Technical Reports Server (NTRS)

    He, Qiming

    2013-01-01

    A software prototype allows users to backup and restore data to/from both public and private cloud storage such as Amazon's S3 and NASA's Nebula. Unlike other off-the-shelf tools, this software ensures user data security in the cloud (through encryption), and minimizes users operating costs by using space- and bandwidth-efficient compression and incremental backup. Parallel data processing utilities have also been developed by using massively scalable cloud computing in conjunction with cloud storage. One of the innovations in this software is using modified open source components to work with a private cloud like NASA Nebula. Another innovation is porting the complex backup to- cloud software to embedded Linux, running on the home networking devices, in order to benefit more users.

  8. Highly Efficient Hybrid Polymer and Amorphous Silicon Multijunction Solar Cells with Effective Optical Management.

    PubMed

    Tan, Hairen; Furlan, Alice; Li, Weiwei; Arapov, Kirill; Santbergen, Rudi; Wienk, Martijn M; Zeman, Miro; Smets, Arno H M; Janssen, René A J

    2016-03-16

    Highly efficient hybrid multijunction solar cells are constructed with a wide-bandgap amorphous silicon for the front subcell and a low-bandgap polymer for the back subcell. Power conversion efficiencies of 11.6% and 13.2% are achieved in tandem and triple-junction configurations, respectively. The high efficiencies are enabled by deploying effective optical management and by using photoactive materials with complementary absorption. PMID:26780260

  9. Tabled Execution in Scheme

    SciTech Connect

    Willcock, J J; Lumsdaine, A; Quinlan, D J

    2008-08-19

    Tabled execution is a generalization of memorization developed by the logic programming community. It not only saves results from tabled predicates, but also stores the set of currently active calls to them; tabled execution can thus provide meaningful semantics for programs that seemingly contain infinite recursions with the same arguments. In logic programming, tabled execution is used for many purposes, both for improving the efficiency of programs, and making tasks simpler and more direct to express than with normal logic programs. However, tabled execution is only infrequently applied in mainstream functional languages such as Scheme. We demonstrate an elegant implementation of tabled execution in Scheme, using a mix of continuation-passing style and mutable data. We also show the use of tabled execution in Scheme for a problem in formal language and automata theory, demonstrating that tabled execution can be a valuable tool for Scheme users.

  10. A case-study of landfill minimization and material recovery via waste co-gasification in a new waste management scheme

    SciTech Connect

    Tanigaki, Nobuhiro; Ishida, Yoshihiro; Osada, Morihiro

    2015-03-15

    Highlights: • A new waste management scheme and the effects of co-gasification of MSW were assessed. • A co-gasification system was compared with other conventional systems. • The co-gasification system can produce slag and metal with high-quality. • The co-gasification system showed an economic advantage when bottom ash is landfilled. • The sensitive analyses indicate an economic advantage when the landfill cost is high. - Abstract: This study evaluates municipal solid waste co-gasification technology and a new solid waste management scheme, which can minimize final landfill amounts and maximize material recycled from waste. This new scheme is considered for a region where bottom ash and incombustibles are landfilled or not allowed to be recycled due to their toxic heavy metal concentration. Waste is processed with incombustible residues and an incineration bottom ash discharged from existent conventional incinerators, using a gasification and melting technology (the Direct Melting System). The inert materials, contained in municipal solid waste, incombustibles and bottom ash, are recycled as slag and metal in this process as well as energy recovery. Based on this new waste management scheme with a co-gasification system, a case study of municipal solid waste co-gasification was evaluated and compared with other technical solutions, such as conventional incineration, incineration with an ash melting facility under certain boundary conditions. From a technical point of view, co-gasification produced high quality slag with few harmful heavy metals, which was recycled completely without requiring any further post-treatment such as aging. As a consequence, the co-gasification system had an economical advantage over other systems because of its material recovery and minimization of the final landfill amount. Sensitivity analyses of landfill cost, power price and inert materials in waste were also conducted. The higher the landfill costs, the greater the

  11. [Exclusive radiotherapy and concurrent endocrine therapy for the management of elderly breast cancer patients: case study and review of hypofractionated schemes].

    PubMed

    Auberdiac, P; Chargari, C; Cartier, L; Mélis, A; Malkoun, N; Chauleur, C; Jacquin, J-P; de Laroche, G; Magné, N

    2011-12-01

    Normofractionated radiotherapy is standard for adjuvant management of patients treated with breast conservative surgery for breast cancer. However, many elderly patients are not eligible to such strategy, either because of concurrent diseases, or because the tumor is inoperable. Several protocols of exclusive radiotherapy have been reported in the literature, frequently using hypofractionated radiotherapy and endocrine therapy. We report a case of a patient treated with exclusive endocrine and radiotherapy and address the state of the art on hypofractionated schemes for the management of elderly breast cancer patients. While hypofractionated radiotherapy does not compromise the oncologic or cosmetic outcome, there is no prospective data that assesses the place of radiotherapy for the exclusive treatment of elderly patients. This strategy should be further assessed in clinical randomized trial.

  12. A case-study of landfill minimization and material recovery via waste co-gasification in a new waste management scheme.

    PubMed

    Tanigaki, Nobuhiro; Ishida, Yoshihiro; Osada, Morihiro

    2015-03-01

    This study evaluates municipal solid waste co-gasification technology and a new solid waste management scheme, which can minimize final landfill amounts and maximize material recycled from waste. This new scheme is considered for a region where bottom ash and incombustibles are landfilled or not allowed to be recycled due to their toxic heavy metal concentration. Waste is processed with incombustible residues and an incineration bottom ash discharged from existent conventional incinerators, using a gasification and melting technology (the Direct Melting System). The inert materials, contained in municipal solid waste, incombustibles and bottom ash, are recycled as slag and metal in this process as well as energy recovery. Based on this new waste management scheme with a co-gasification system, a case study of municipal solid waste co-gasification was evaluated and compared with other technical solutions, such as conventional incineration, incineration with an ash melting facility under certain boundary conditions. From a technical point of view, co-gasification produced high quality slag with few harmful heavy metals, which was recycled completely without requiring any further post-treatment such as aging. As a consequence, the co-gasification system had an economical advantage over other systems because of its material recovery and minimization of the final landfill amount. Sensitivity analyses of landfill cost, power price and inert materials in waste were also conducted. The higher the landfill costs, the greater the advantage of the co-gasification system has. The co-gasification was beneficial for landfill cost in the range of 80 Euro per ton or more. Higher power prices led to lower operation cost in each case. The inert contents in processed waste had a significant influence on the operating cost. These results indicate that co-gasification of bottom ash and incombustibles with municipal solid waste contributes to minimizing the final landfill amount and has

  13. Efficient water use in California: Conjunctive management of ground and surface reservoirs

    NASA Astrophysics Data System (ADS)

    Jaquette, David J.

    1981-05-01

    In 1976, the California State Assembly, through the Committee on Water, Parks and Wildlife, and the Rockefeller Foundation, funded a two-year Rand Corp. study of California's water-use efficiency. This study has produced a wide variety of policy recommendations designed to improve the efficiency of water use in the State. This report documents one of the areas of the research, groundwater conjunctive management.

  14. Facile Synthesis of Novel Redox-Mediator-free Direct Z-Scheme CaIn2S4 Marigold-Flower-like/TiO2 Photocatalysts with Superior Photocatalytic Efficiency.

    PubMed

    Jo, Wan-Kuen; Sivakumar Natarajan, Thillai

    2015-08-12

    Novel redox-mediator-free direct Z-scheme CaIn2S4 marigold-flower-like/TiO2 (CIS/TNP) photocatalysts with different CaIn2S4 weight percentages were synthesized using a facile wet-impregnation method. Uniform hierarchical marigold-flower-like CaIn2S4 (CIS) microspheres were synthesized using a hydrothermal method. Field-emission scanning electron microscopy and transmission electron microscopy analyses suggested that the formation and aggregation of nanoparticles, followed by the growth of petals or sheets and their subsequent self-assembly, led to the formation of the uniform hierarchical marigold-flower-like CIS structures. The photocatalytic degradation efficiency of the direct Z-scheme CIS/TNP photocatalysts was evaluated through the degradation of the pharmaceutical compounds isoniazid (ISN) and metronidazole (MTZ). The direct Z-scheme CaIn2S4 marigold-flower-like/TiO2 (1%-CIS/TNP) photocatalyst showed enhanced performance in the ISN (71.9%) and MTZ (86.5%) photocatalytic degradations as compared to composites with different CaIn2S4 contents or the individual TiO2 and CaIn2S4. A possible enhancement mechanism based on the Z-scheme formed between the CIS and TNP for the improved photocatalytic efficiency was also proposed. The recombination rate of the photoinduced charge carriers was significantly suppressed for the direct Z-scheme CIS/TNP photocatalyst, which was confirmed by photoluminescence analysis. Radical-trapping studies revealed that photogenerated holes (h+), •OH, and O2•- are the primary active species, and suggested that the enhanced photocatalytic efficiency of the 1%-CIS/TNP follows the Z-scheme mechanism for transferring the charge carriers. It was further confirmed by hydroxyl (•OH) radical determination via fluorescence techniques revealed that higher concentration of •OH radical were formed over 1%-CIS/TNP than over bare CIS and TNP. The separation of the charge carriers was further confirmed using photocurrent and electron spin

  15. Domestic Banks in Bangladesh Could Ensure Efficiency by Improving Human Resource Management Practices

    PubMed Central

    Muhammad Masum, Abdul Kadar; Azad, Md. Abul Kalam; Hoque, Kazi Enamul; Beh, Loo-See

    2015-01-01

    The paper aims to examine the influence of human resource management (HRM) practices on bank efficiency using Malmquist index of total factor productivity. The model comprises HRM index that represents the quality of HRM practices. The results are decomposed into three efficiency scores, namely, technical efficiency, pure efficiency, and scale efficiency. In this study, panel data for 44 banks in Bangladesh are used for the period 2008-2013. This paper reveals that foreign banks are ahead in converting the influence of HRM practices into efficiency scores (0.946>0.833). On the other hand, domestic banks performed better than foreign banks in terms of pure efficiency and scale efficiency. But, in terms of technical efficiency, the domestic banks are regressed by 6.7% annually whereas foreign banks are progressed with a yearly value of 5.8%. The results are robust, because the Mann-Whitney test and Kruskall-Wallis test (non-parametric tests) also confirm the same results. This study emphasizes HRM practices in the banking industry to ensure efficiency in the long-term scenario. Domestic banks are suggested to ensure continuous development in HRM practices in order to compete with foreign banks. PMID:26221727

  16. Domestic Banks in Bangladesh Could Ensure Efficiency by Improving Human Resource Management Practices.

    PubMed

    Masum, Abdul Kadar Muhammad; Azad, Md Abul Kalam; Hoque, Kazi Enamul; Beh, Loo-See

    2015-01-01

    The paper aims to examine the influence of human resource management (HRM) practices on bank efficiency using Malmquist index of total factor productivity. The model comprises HRM index that represents the quality of HRM practices. The results are decomposed into three efficiency scores, namely, technical efficiency, pure efficiency, and scale efficiency. In this study, panel data for 44 banks in Bangladesh are used for the period 2008-2013. This paper reveals that foreign banks are ahead in converting the influence of HRM practices into efficiency scores (0.946>0.833). On the other hand, domestic banks performed better than foreign banks in terms of pure efficiency and scale efficiency. But, in terms of technical efficiency, the domestic banks are regressed by 6.7% annually whereas foreign banks are progressed with a yearly value of 5.8%. The results are robust, because the Mann-Whitney test and Kruskall-Wallis test (non-parametric tests) also confirm the same results. This study emphasizes HRM practices in the banking industry to ensure efficiency in the long-term scenario. Domestic banks are suggested to ensure continuous development in HRM practices in order to compete with foreign banks. PMID:26221727

  17. Domestic Banks in Bangladesh Could Ensure Efficiency by Improving Human Resource Management Practices.

    PubMed

    Masum, Abdul Kadar Muhammad; Azad, Md Abul Kalam; Hoque, Kazi Enamul; Beh, Loo-See

    2015-01-01

    The paper aims to examine the influence of human resource management (HRM) practices on bank efficiency using Malmquist index of total factor productivity. The model comprises HRM index that represents the quality of HRM practices. The results are decomposed into three efficiency scores, namely, technical efficiency, pure efficiency, and scale efficiency. In this study, panel data for 44 banks in Bangladesh are used for the period 2008-2013. This paper reveals that foreign banks are ahead in converting the influence of HRM practices into efficiency scores (0.946>0.833). On the other hand, domestic banks performed better than foreign banks in terms of pure efficiency and scale efficiency. But, in terms of technical efficiency, the domestic banks are regressed by 6.7% annually whereas foreign banks are progressed with a yearly value of 5.8%. The results are robust, because the Mann-Whitney test and Kruskall-Wallis test (non-parametric tests) also confirm the same results. This study emphasizes HRM practices in the banking industry to ensure efficiency in the long-term scenario. Domestic banks are suggested to ensure continuous development in HRM practices in order to compete with foreign banks.

  18. Simulating long-term effectiveness and efficiency of management scenarios for an invasive grass

    USGS Publications Warehouse

    Jarnevich, Catherine S.; Holcombe, Tracy R.; Cullinane Thomas, Catherine; Frid, Leonardo; Olsson, Aaryn D.

    2015-01-01

    Resource managers are often faced with trade-offs in allocating limited resources to manage plant invasions. These decisions must often be made with uncertainty about the location of infestations, their rate of spread and effectiveness of management actions. Landscape level simulation tools such as state-and-transition simulation models (STSMs) can be used to evaluate the potential long term consequences of alternative management strategies and help identify those strategies that make efficient use of resources. We analyzed alternative management scenarios for African buffelgrass (Pennisetum ciliare syn. Cenchrus ciliaris) at Ironwood Forest National Monument, Arizona using a spatially explicit STSM implemented in the Tool for Exploratory Landscape Scenario Analyses (TELSA). Buffelgrass is an invasive grass that is spreading rapidly in the Sonoran Desert, affecting multiple habitats and jurisdictions. This invasion is creating a novel fire risk and transforming natural ecosystems. The model used in this application incorporates buffelgrass dispersal and establishment and management actions and effectiveness including inventory, treatment and post-treatment maintenance. We simulated 11 alternative scenarios developed in consultation with buffelgrass managers and other stakeholders. The scenarios vary according to the total budget allocated for management and the allocation of that budget between different kinds of management actions. Scenario results suggest that to achieve an actual reduction and stabilization of buffelgrass populations, management unconstrained by fiscal restrictions and across all jurisdictions and private lands is required; without broad and aggressive management, buffelgrass populations are expected to increase over time. However, results also suggest that large upfront investments can achieve control results that require relatively minimal spending in the future. Investing the necessary funds upfront to control the invasion results in the most

  19. Biomass production efficiency controlled by management in temperate and boreal ecosystems

    NASA Astrophysics Data System (ADS)

    Campioli, M.; Vicca, S.; Luyssaert, S.; Bilcke, J.; Ceschia, E.; Chapin, F. S., III; Ciais, P.; Fernández-Martínez, M.; Malhi, Y.; Obersteiner, M.; Olefeldt, D.; Papale, D.; Piao, S. L.; Peñuelas, J.; Sullivan, P. F.; Wang, X.; Zenone, T.; Janssens, I. A.

    2015-11-01

    Plants acquire carbon through photosynthesis to sustain biomass production, autotrophic respiration and production of non-structural compounds for multiple purposes. The fraction of photosynthetic production used for biomass production, the biomass production efficiency, is a key determinant of the conversion of solar energy to biomass. In forest ecosystems, biomass production efficiency was suggested to be related to site fertility. Here we present a database of biomass production efficiency from 131 sites compiled from individual studies using harvest, biometric, eddy covariance, or process-based model estimates of production. The database is global, but dominated by data from Europe and North America. We show that instead of site fertility, ecosystem management is the key factor that controls biomass production efficiency in terrestrial ecosystems. In addition, in natural forests, grasslands, tundra, boreal peatlands and marshes, biomass production efficiency is independent of vegetation, environmental and climatic drivers. This similarity of biomass production efficiency across natural ecosystem types suggests that the ratio of biomass production to gross primary productivity is constant across natural ecosystems. We suggest that plant adaptation results in similar growth efficiency in high- and low-fertility natural systems, but that nutrient influxes under managed conditions favour a shift to carbon investment from the belowground flux of non-structural compounds to aboveground biomass.

  20. Thinking Globally: How ISO 50001 - Energy Management can make industrial energy efficiency standard practice

    SciTech Connect

    McKane, Aimee; Desai, Deann; Matteini, Marco; Meffert, William; Williams, Robert; Risser, Roland

    2009-08-01

    Industry utilizes very complex systems, consisting of equipment and their human interface, which are organized to meet the production needs of the business. Effective and sustainable energy efficiency programs in an industrial setting require a systems approach to optimize the integrated whole while meeting primary business requirements. Companies that treat energy as a manageable resource and integrate their energy program into their management practices have an organizational context to continually seek opportunities for optimizing their energy use. The purpose of an energy management system standard is to provide guidance for industrial and commercial facilities to integrate energy efficiency into their management practices, including fine-tuning production processes and improving the energy efficiency of industrial systems. The International Organization for Standardization (ISO) has identified energy management as one of its top five priorities for standards development. The new ISO 50001 will establish an international framework for industrial, commercial, or institutional facilities, or entire companies, to manage their energy, including procurement and use. This standard is expected to achieve major, long-term increases in energy efficiency (20percent or more) in industrial, commercial, and institutional facilities and to reduce greenhouse gas (GHG) emissions worldwide.This paper describes the impetus for the international standard, its purpose, scope and significance, and development progress to date. A comparative overview of existing energy management standards is provided, as well as a discussion of capacity-building needs for skilled individuals to assist organizations in adopting the standard. Finally, opportunities and challenges are presented for implementing ISO 50001 in emerging economies and developing countries.

  1. Study on Providing Professors with Efficient Service Based on Time Management Strategy

    ERIC Educational Resources Information Center

    Li, Chunlin; Liu, Mengchao; Wang, Yining

    2016-01-01

    Time management is the study to use time scientifically by deploying skills, techniques and means, and maximizing time value to help individuals or organizations efficiently complete tasks and achieve goals. University professor as a body is an important force in teaching and research. In order to ensure high-quality teaching, productive research,…

  2. Use of GIS-based Site-specific Nitrogen Management for Improving Energy Efficiency

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To our knowledge, geographical information system (GIS)-based site-specific nitrogen management (SSNM) techniques have not been used to assess agricultural energy costs and efficiency. This chapter uses SSNM case studies for corn (Zea mays L.) grown in Missouri and cotton (Gossypium hirsutum L.) gro...

  3. Use of GIS-based site-specific nitrogen management for improving energy efficiency

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nitrogen (N) is a significant energy component of in support of crop production but it can be highly variable within fields. To our knowledge, no efforts have been made to employ GIS-based site-specific N management (SSNM) to assess and improve energy costs and efficiency. We examine recent SSNM ca...

  4. Human Resource Management Strategies and Teacher's Efficiency within Schools: A Co-Relational Study

    ERIC Educational Resources Information Center

    Hashmi, Kiran

    2014-01-01

    The aim of the paper is to study Human Resource Management and Development (HRMD) strategies and their effect on teachers' efficiency within the Catholic Board of Education (CBE) schools of Pakistan whose teachers are graduates in educational leadership courses from a private teacher education institutes in Karachi. The study endeavored to build a…

  5. Classified and clustered data constellation: An efficient approach of 3D urban data management

    NASA Astrophysics Data System (ADS)

    Azri, Suhaibah; Ujang, Uznir; Castro, Francesc Antón; Rahman, Alias Abdul; Mioc, Darka

    2016-03-01

    The growth of urban areas has resulted in massive urban datasets and difficulties handling and managing issues related to urban areas. Huge and massive datasets can degrade data retrieval and information analysis performance. In addition, the urban environment is very difficult to manage because it involves various types of data, such as multiple types of zoning themes in the case of urban mixed-use development. Thus, a special technique for efficient handling and management of urban data is necessary. This paper proposes a structure called Classified and Clustered Data Constellation (CCDC) for urban data management. CCDC operates on the basis of two filters: classification and clustering. To boost up the performance of information retrieval, CCDC offers a minimal percentage of overlap among nodes and coverage area to avoid repetitive data entry and multipath query. The results of tests conducted on several urban mixed-use development datasets using CCDC verify that it efficiently retrieves their semantic and spatial information. Further, comparisons conducted between CCDC and existing clustering and data constellation techniques, from the aspect of preservation of minimal overlap and coverage, confirm that the proposed structure is capable of preserving the minimum overlap and coverage area among nodes. Our overall results indicate that CCDC is efficient in handling and managing urban data, especially urban mixed-use development applications.

  6. a Hadoop-Based Distributed Framework for Efficient Managing and Processing Big Remote Sensing Images

    NASA Astrophysics Data System (ADS)

    Wang, C.; Hu, F.; Hu, X.; Zhao, S.; Wen, W.; Yang, C.

    2015-07-01

    Various sensors from airborne and satellite platforms are producing large volumes of remote sensing images for mapping, environmental monitoring, disaster management, military intelligence, and others. However, it is challenging to efficiently storage, query and process such big data due to the data- and computing- intensive issues. In this paper, a Hadoop-based framework is proposed to manage and process the big remote sensing data in a distributed and parallel manner. Especially, remote sensing data can be directly fetched from other data platforms into the Hadoop Distributed File System (HDFS). The Orfeo toolbox, a ready-to-use tool for large image processing, is integrated into MapReduce to provide affluent image processing operations. With the integration of HDFS, Orfeo toolbox and MapReduce, these remote sensing images can be directly processed in parallel in a scalable computing environment. The experiment results show that the proposed framework can efficiently manage and process such big remote sensing data.

  7. Enhancing DSN Operations Efficiency with the Discrepancy Reporting Management System (DRMS)

    NASA Technical Reports Server (NTRS)

    Chatillon, Mark; Lin, James; Cooper, Tonja M.

    2003-01-01

    The DRMS is the Discrepancy Reporting Management System used by the Deep Space Network (DSN). It uses a web interface and is a management tool designed to track and manage: data outage incidents during spacecraft tracks against equipment and software known as DRs (discrepancy Reports), to record "out of pass" incident logs against equipment and software in a Station Log, to record instances where equipment has be restarted or reset as Reset records, and to electronically record equipment readiness status across the DSN. Tracking and managing these items increases DSN operational efficiency by providing: the ability to establish the operational history of equipment items, data on the quality of service provided to the DSN customers, the ability to measure service performance, early insight into processes, procedures and interfaces that may need updating or changing, and the capability to trace a data outage to a software or hardware change. The items listed above help the DSN to focus resources on areas of most need.

  8. Neutronics and Depletion Methods for Parametric Studies of Fluoride Salt Cooled High Temperature Reactors with Slab Fuel Geometry and Multi-Batch Fuel Management Schemes

    SciTech Connect

    Cisneros, Anselmo T.; Ilas, Dan

    2012-01-01

    The Advanced High Temperature Reactor (AHTR) is a 3400 MWth fluoride salt cooled high temperature reactor (FHR) that uses TRISO particle fuel compacted into slabs rather than spherical fuel pebbles or cylindrical fuel compacts. Simplified methods are required for parametric design studies such that analyzing the entire feasible design space for an AHTR is tractable. These simplifications include fuel homogenization techniques to increase the speed of neutron transport calculations in depletion analysis and equilibrium depletion analysis methods to analyze systems with multi-batch fuel management schemes. This paper presents three elements of significant novelty. First, the reactivity-equivalent physical transformation (RPT) methodology usually applied in systems with coated particle fuel in cylindrical and spherical geometries was extended to slab geometries. Secondly, based on this newly developed RPT method for slab geometries, a methodology that uses Monte Carlo depletion approaches was further developed to search for the maximum discharge burnup in a multi-batch system by iteratively estimating the beginning of equilibrium cycle composition and sampling different discharge burnups. This iterative equilibrium depletion search (IEDS) method fully defines an equilibrium fuel cycle (keff, power, flux and composition evolutions across space and time), but is computationally demanding, although feasible on single-processor workstations. Finally, an analytical method, the non-linear reactivity model, was developed by expanding the linear reactivity model to include an arbitrary number of higher order terms to extrapolate single-batch depletion results to estimate the maximum discharge burnup and BOEC keff in systems with multi-batch fuel management schemes. Results from this method were benchmarked against equilibrium depletion analysis results using the IEDS.

  9. Neutronics and Depletion Methods for Parametric Studies of Fluoride Salt Cooled High Temperature Reactors with Slab Fuel Geometry and Multi-Batch Fuel Management Schemes

    SciTech Connect

    Cisneros, Anselmo T.; Ilas, Dan

    2013-01-01

    The Advanced High-Temperature Reactor (AHTR) is a 3400 MWth fluoride-salt-cooled high-temperature reactor (FHR) that uses TRISO particle fuel compacted into slabs rather than spherical or cylindrical fuel compacts. Simplified methods are required for parametric design studies such that analyzing the entire feasible design space for an AHTR is tractable. These simplifications include fuel homogenization techniques to increase the speed of neutron transport calculations in depletion analysis and equilibrium depletion analysis methods to analyze systems with multi-batch fuel management schemes. This paper presents three elements of significant novelty. First, the Reactivity-Equivalent Physical Transformation (RPT) methodology usually applied in systems with coated-particle fuel in cylindrical and spherical geometries has been extended to slab geometries. Secondly, based on this newly developed RPT method for slab geometries, a methodology that uses Monte Carlo depletion approaches was further developed to search for the maximum discharge burnup in a multi-batch system by iteratively estimating the beginning of equilibrium cycle (BOEC) composition and sampling different discharge burnups. This Iterative Equilibrium Depletion Search (IEDS) method fully defines an equilibrium fuel cycle (keff, power, flux, and composition evolutions) but is computationally demanding, although feasible on single-processor workstations. Finally, an analytical method, the Non-Linear Reactivity Model, was developed by expanding the linear reactivity model to include an arbitrary number of higher order terms so that single-batch depletion results could be extrapolated to estimate the maximum discharge burnup and BOEC keff in systems with multi-batch fuel management schemes. Results from this method were benchmarked against equilibrium depletion analysis results using the IEDS.

  10. Nitrogen retention efficiency and nitrogen losses of a managed and phytodiverse temperate grassland

    NASA Astrophysics Data System (ADS)

    Keuter, A.

    2012-04-01

    In consequence of the increasing global population, it is necessary to keep N losses at the minimum while maintaining soil fertility and high yields. The goal of our study was to assess how management practices and sward functional diversity affected N losses and N retention efficiency in a temperate grassland. We measured N retention efficiency as the ratio of N losses (N2O emission and NO3- and DON leaching) to soil available N (gross N mineralization rates). Our study was conducted in a grassland management experiment (GRASSMAN) located in Solling, Germany; the experimental design was three-factorial with two mowing frequencies (cut once and thrice per year), two fertilization treatments (180 - 30 - 100 kg NPK ha-1 yr-1 and no fertilization), and three sward compositions (dicot-enhanced swards with nearly equal proportions of dicots and monocots, control swards with ~ 70% monocots and ~ 30% dicots and monocot-enhanced swards with ~90% monocots and 10% dicots). N2O emission and NO3 leaching were significantly increased by fertilization and decreased by more frequent mowing. An interaction between these factors showed that frequent mowing can mitigate the negative effects of fertilization on N losses. N retention efficiency was largely influenced by fertilization and sward composition: N retention efficiencies were larger in unfertilized plots than fertilized plots, and decreased in the order of control > dicot-enhanced > monocot-enhanced swards. Microbial N immobilization turned out to be more important for N retention than plant N uptake. We concluded that over the past 5 decades the prevailing management practices have led to an equilibrium sward composition in this grassland ecosystem in which optimal proportions of monocots and dicots (i.e. unmanipulated control plots) developed to maximize N retention efficiency. Deviations from these proportions reduce N retention efficiency.

  11. Eco-efficiency in contaminated land management in Finland: barriers and development needs.

    PubMed

    Sorvari, Jaana; Antikainen, Riina; Kosola, Marja-Leena; Hokkanen, Pekka; Haavisto, Teija

    2009-04-01

    In Finland the number of potentially contaminated sites totals ca. 20 000. The annual costs of remediation are 60-70 million euros. Excavation combined with disposal or off-site treatment is the most common soil remediation method. To define which factors make contaminated land management (CLM) eco-efficient and to study whether eco-efficiency has been considered in CLM decisions we carried out a literature survey, two stakeholder seminars, thematic interviews and a questionnaire study on economic instruments. Generally speaking, eco-efficiency means gaining environmental benefits with fewer resources. To assess its realization in CLM, it is necessary to have a more specific definition. In our study, we arrived at a list of several qualifications for eco-efficiency. It was also shown that eco-efficiency has hardly been a real issue in the selection of remediation techniques or generally, in the decision-making concerning contaminated sites. The existing policy instruments seem to be insufficient to promote eco-efficiency in CLM. Several concrete barriers to eco-efficiency also came up, urgency and lack of money being the most important. The scarcity of the use of in situ remediation methods and the difficulties involved in recycling slightly contaminated or treated soil were considered to be major problems. Insufficient site studies, inadequate or unsuitable methods for risk assessment and cost evaluation, and deficient and mistimed risk communication can also hinder the realization of eco-efficiency. Hence, there is a need to promote the use of more eco-efficient remediation techniques and to develop CLM policy instruments, guidelines, and participatory processes and methods to assess the eco-efficiency of CLM options.

  12. Efficient Visible-Light-Driven Z-Scheme Overall Water Splitting Using a MgTa2O(6-x)N(y)/TaON Heterostructure Photocatalyst for H2 Evolution.

    PubMed

    Chen, Shanshan; Qi, Yu; Hisatomi, Takashi; Ding, Qian; Asai, Tomohiro; Li, Zheng; Ma, Su Su Khine; Zhang, Fuxiang; Domen, Kazunari; Li, Can

    2015-07-13

    An (oxy)nitride-based heterostructure for powdered Z-scheme overall water splitting is presented. Compared with the single MgTa2O(6-x)N(y) or TaON photocatalyst, a MgTa2O(6-x)N(y)/TaON heterostructure fabricated by a simple one-pot nitridation route was demonstrated to effectively suppress the recombination of carriers by efficient spatial charge separation and decreased defect density. By employing Pt-loaded MgTa2O(6-x)N(y)/TaON as a H2-evolving photocatalyst, a Z-scheme overall water splitting system with an apparent quantum efficiency (AQE) of 6.8% at 420 nm was constructed (PtO(x)-WO3 and IO3(-)/I(-) pairs were used as an O2-evolving photocatalyst and a redox mediator, respectively), the activity of which is circa 7 or 360 times of that using Pt-TaON or Pt-MgTa2O(6-x)N)y) as a H2-evolving photocatalyst, respectively. To the best of our knowledge, this is the highest AQE among the powdered Z-scheme overall water splitting systems ever reported. PMID:26037473

  13. Efficient Visible-Light-Driven Z-Scheme Overall Water Splitting Using a MgTa2O(6-x)N(y)/TaON Heterostructure Photocatalyst for H2 Evolution.

    PubMed

    Chen, Shanshan; Qi, Yu; Hisatomi, Takashi; Ding, Qian; Asai, Tomohiro; Li, Zheng; Ma, Su Su Khine; Zhang, Fuxiang; Domen, Kazunari; Li, Can

    2015-07-13

    An (oxy)nitride-based heterostructure for powdered Z-scheme overall water splitting is presented. Compared with the single MgTa2O(6-x)N(y) or TaON photocatalyst, a MgTa2O(6-x)N(y)/TaON heterostructure fabricated by a simple one-pot nitridation route was demonstrated to effectively suppress the recombination of carriers by efficient spatial charge separation and decreased defect density. By employing Pt-loaded MgTa2O(6-x)N(y)/TaON as a H2-evolving photocatalyst, a Z-scheme overall water splitting system with an apparent quantum efficiency (AQE) of 6.8% at 420 nm was constructed (PtO(x)-WO3 and IO3(-)/I(-) pairs were used as an O2-evolving photocatalyst and a redox mediator, respectively), the activity of which is circa 7 or 360 times of that using Pt-TaON or Pt-MgTa2O(6-x)N)y) as a H2-evolving photocatalyst, respectively. To the best of our knowledge, this is the highest AQE among the powdered Z-scheme overall water splitting systems ever reported.

  14. Increased project efficiency using telemetry technology as part of an integrated data management system

    SciTech Connect

    White, D.R.

    1996-12-31

    Until recently, the use of telemetry in the environmental consulting industry has generally been limited to large scale projects and the occasional collection of equipment or field instrumentation data from environmental remediation hardware. With today`s ever increasing personal computer processing power and decreasing prices, telemetry based management is feasible for smaller scale projects. With the increased focus on cost reduction within the environmental industry, successful project managers will take advantage of increased efficiencies available through the use of telemetry. Like any tool though, those that use it must understand how to make use of telemetry technology from raw data collection through data reduction and analysis to production of the final report.

  15. Non-blood medical care in gynecologic oncology: a review and update of blood conservation management schemes

    PubMed Central

    2011-01-01

    This review attempts to outline the alternative measures and interventions used in bloodless surgery in the field of gynecologic oncology and demonstrate their effectiveness. Nowadays, as increasingly more patients are expressing their fears concerning the potential risks accompanying allogenic transfusion of blood products, putting the theory of bloodless surgery into practice seems to gaining greater acceptance. An increasing number of institutions appear to be successfully adopting approaches that minimize blood usage for all patients treated for gynecologic malignancies. Preoperative, intraoperative and postoperative measures are required, such as optimization of red blood cell mass, adequate preoperative plan and invasive hemostatic procedures, assisting anesthetic techniques, individualization of anemia tolerance, autologous blood donation, normovolemic hemodilution, intraoperative cell salvage and pharmacologic agents for controlling blood loss. An individualised management plan of experienced personnel adopting a multidisciplinary team approach should be available to establish non-blood management strategies, and not only on demand of the patient, in the field of gynecologic oncology with the use of drugs, devices and surgical-medical techniques. PMID:22051161

  16. Developing a multi-pollutant conceptual framework for the selection and targeting of interventions in water industry catchment management schemes.

    PubMed

    Bloodworth, J W; Holman, I P; Burgess, P J; Gillman, S; Frogbrook, Z; Brown, P

    2015-09-15

    In recent years water companies have started to adopt catchment management to reduce diffuse pollution in drinking water supply areas. The heterogeneity of catchments and the range of pollutants that must be removed to meet the EU Drinking Water Directive (98/83/EC) limits make it difficult to prioritise areas of a catchment for intervention. Thus conceptual frameworks are required that can disaggregate the components of pollutant risk and help water companies make decisions about where to target interventions in their catchments to maximum effect. This paper demonstrates the concept of generalising pollutants in the same framework by reviewing key pollutant processes within a source-mobilisation-delivery context. From this, criteria are developed (with input from water industry professionals involved in catchment management) which highlights the need for a new water industry specific conceptual framework. The new CaRPoW (Catchment Risk to Potable Water) framework uses the Source-Mobilisation-Delivery concept as modular components of risk that work at two scales, source and mobilisation at the field scale and delivery at the catchment scale. Disaggregating pollutant processes permits the main components of risk to be ascertained so that appropriate interventions can be selected. The generic structure also allows for the outputs from different pollutants to be compared so that potential multiple benefits can be identified. CaRPow provides a transferable framework that can be used by water companies to cost-effectively target interventions under current conditions or under scenarios of land use or climate change.

  17. Public sector energy management: A strategy for catalyzing energy efficiency in Malaysia

    NASA Astrophysics Data System (ADS)

    Roy, Anish Kumar

    To date the public sector role in facilitating the transition to a sustainable energy future has been envisaged mainly from a regulatory perspective. In such a role, the public sector provides the push factors---enforcing regulations and providing incentives---to correct market imperfections that impede energy transitions. An alternative and complementary role of the public sector that is now gaining increasing attention is that of catalyzing energy transitions through public sector energy management initiatives. This dissertation offers a conceptual framework to rationalize such a role for the public sector by combining recent theories of sustainable energy transition and public management. In particular, the framework identifies innovative public management strategies (such as performance contracting and procurement) for effectively implementing sustainable energy projects in government facilities. The dissertation evaluates a model of sustainable public sector energy management for promoting energy efficiency in Malaysia. The public sector in Malaysia can be a major player in leading and catalyzing energy efficiency efforts as it is not only the largest and one of the most influential energy consumers, but it also plays a central role in setting national development strategy. The dissertation makes several recommendations on how a public sector energy management strategy can be implemented in Malaysia. The US Federal Energy Management Program (FEMP) is used as a practical model. The analysis, however, shows that in applying the FEMP model to the Malaysian context, there are a number of limitations that will have to be taken into consideration to enable a public sector energy management strategy to be effectively implemented. Overall the analysis of this dissertation contributes to a rethinking of the public sector role in sustainable energy development that can strengthen the sector's credibility both in terms of governance and institutional performance. In

  18. Decision Support System for an efficient irrigation water management in semi arid environment

    NASA Astrophysics Data System (ADS)

    Khan, M. A.; Islam, M.; Hafeez, M. M.; Flugel, W. A.

    2009-12-01

    A significant increase in agricultural productivity over the last few decades has protected the world from episodes of hunger and food shortages. Water management in irrigated agriculture was instrumental in achieving those gains. Water resources are under high pressure due to rapid population growth and increased competition among various sectors. Access to reliable data on water availability, quantity and quality can provide the necessary foundation for sound management of water resources. There are many traditional methods for matching water demand and supply, however imbalances between demand and supply remain inevitable. It is possible to reduce the imbalances considerably through development of appropriate irrigation water management tool that take into account various factors such as soil type, irrigation water supply, and crop water demand. All components of water balance need to be understood and quantified for efficient and sustainable management of water resources. Application of an intelligent Decision Support System (DSS) is becoming significant. A DSS incorporates knowledge and expertise within the decision support framework. It is an integrated set of data, functions, models and other relevant information that efficiently processes input data, simulates models and displays the results in a user friendly format. It helps in decision-making process, to analyse the problem and explore various scenarios to make the most appropriate decision for water management. This paper deals with the Coleambally Irrigation Area (CIA) located in Murrumbidgee catchment, NSW, Australia. An Integrated River Information System called Coleambally IRIS has been developed to improve the irrigation water management ranging from farm to sub-system and system level. It is a web-based information management system with a focus on time series and geospatial hydrological, climatic and remote sensing data including land cover class, surface temperature, soil moisture, Normalized

  19. General purpose software for efficient uncertainty management of large finite element models

    PubMed Central

    Patelli, Edoardo; Murat Panayirci, H.; Broggi, Matteo; Goller, Barbara; Beaurepaire, Pierre; Pradlwarter, Helmut J.; Schuëller, Gerhart I.

    2012-01-01

    The aim of this paper is to demonstrate that stochastic analyses can be performed on large and complex models within affordable costs. Stochastic analyses offer a much more realistic approach for analysis and design of components and systems although generally computationally demanding. Hence, resorting to efficient approaches and high performance computing is required in order to reduce the execution time. A general purpose software that provides an integration between deterministic solvers (i.e. finite element solvers), efficient algorithms for uncertainty management and high performance computing is presented. The software is intended for a wide range of applications, which includes optimization analysis, life-cycle management, reliability and risk analysis, fatigue and fractures simulation, robust design. The applicability of the proposed tools for practical applications is demonstrated by means of a number of case studies of industrial interest involving detailed models. PMID:22474398

  20. Improving energy efficiency via smart building energy management systems. A comparison with policy measures

    SciTech Connect

    Rocha, Paula; Siddiqui, Afzal; Stadler, Michael

    2014-12-09

    In this study, to foster the transition to more sustainable energy systems, policymakers have been approving measures to improve energy efficiency as well as promoting smart grids. In this setting, building managers are encouraged to adapt their energy operations to real-time market and weather conditions. Yet, most fail to do so as they rely on conventional building energy management systems (BEMS) that have static temperature set points for heating and cooling equipment. In this paper, we investigate how effective policy measures are at improving building-level energy efficiency compared to a smart BEMS with dynamic temperature set points. To this end, we present an integrated optimisation model mimicking the smart BEMS that combines decisions on heating and cooling systems operations with decisions on energy sourcing. Using data from an Austrian and a Spanish building, we find that the smart BEMS results in greater reduction in energy consumption than a conventional BEMS with policy measures.

  1. Quantum Signature Scheme with Weak Arbitrator

    NASA Astrophysics Data System (ADS)

    Luo, Ming-Xing; Chen, Xiu-Bo; Yun, Deng; Yang, Yi-Xian

    2012-07-01

    In this paper, we propose one quantum signature scheme with a weak arbitrator to sign classical messages. This scheme can preserve the merits in the original arbitrated scheme with some entanglement resources, and provide a higher efficiency in transmission and reduction the complexity of implementation. The arbitrator is costless and only involved in the disagreement case.

  2. Fabrication of hierarchically structured novel redox-mediator-free ZnIn2S4 marigold flower/Bi2WO6 flower-like direct Z-scheme nanocomposite photocatalysts with superior visible light photocatalytic efficiency.

    PubMed

    Jo, Wan-Kuen; Lee, Joon Yeob; Natarajan, Thillai Sivakumar

    2016-01-14

    Novel, hierarchically nanostructured, redox-mediator-free, direct Z-scheme nanocomposite photocatalysts were synthesized via a facile hydrothermal method followed by wet-impregnation. The photocatalysts had a ZnIn2S4 marigold flower/Bi2WO6 flower-like (ZIS/BW) composition, which led to superior visible-light photocatalytic efficiency with excellent stability and reusability. The hierarchical marigold flower and flower-like morphologies of ZIS and BW were confirmed by FE-SEM and TEM analyses and further revealed that formation of the hierarchical marigold flower-like ZIS structure followed the formation of nanoparticles, growth of the ZIS petals, and self-assembly of these species. Powder X-ray diffraction and UV-visible diffuse reflectance spectroscopy analyses as well as the enhancement in the surface area and pore volume of the composite provide evidence of strong coupling between hierarchical BW and the ZIS nanostructures. The efficiency of the hierarchical direct Z-scheme photocatalysts for photocatalytic decomposition of metronidazole (MTZ) under visible-light irradiation was evaluated. The hierarchically nanostructured ZIS/BW nanocomposites with 50% loading of ZIS exhibited superior visible-light photocatalytic decomposition efficiency (PDE) compared to the composites with other percentages of ZIS and pristine BW. A probable mechanism for the enhanced photocatalytic efficiency of the ZIS/BW composite in MTZ degradation under visible irradiation was proposed. Radical quenching studies demonstrated that h(+), ˙OH, and O2˙(-) are the primary reactive radicals involved, which confirms that the Z-scheme mechanism of transfer of charge carriers accounts for the higher photocatalytic activity. Kinetic analysis revealed that MTZ degradation follows pseudo-first-order kinetics and the reusability of the composite catalyst for up to four cycles confirms the excellent stability of the hierarchical structure. It is concluded that the hierarchical structure of the ZIS

  3. Energy Efficient Thermal Management for Natural Gas Engine Aftertreatment via Active Flow Control

    SciTech Connect

    David K. Irick; Ke Nguyen; Vitacheslav Naoumov; Doug Ferguson

    2005-04-01

    The project is focused on the development of an energy efficient aftertreatment system capable of reducing NOx and methane by 90% from lean-burn natural gas engines by applying active exhaust flow control. Compared to conventional passive flow-through reactors, the proposed scheme cuts supplemental energy by 50%-70%. The system consists of a Lean NOx Trap (LNT) system and an oxidation catalyst. Through alternating flow control, a major amount of engine exhaust flows through a large portion of the LNT system in the absorption mode, while a small amount of exhaust goes through a small portion of the LNT system in the regeneration or desulfurization mode. By periodically reversing the exhaust gas flow through the oxidation catalyst, a higher temperature profile is maintained in the catalyst bed resulting in greater efficiency of the oxidation catalyst at lower exhaust temperatures. The project involves conceptual design, theoretical analysis, computer simulation, prototype fabrication, and empirical studies. This report details the progress during the first twelve months of the project. The primary activities have been to develop the bench flow reactor system, develop the computer simulation and modeling of the reverse-flow oxidation catalyst, install the engine into the test cell, and begin design of the LNT system.

  4. ENERGY EFFICIENT THERMAL MANAGEMENT FOR NATURAL GAS ENGINE AFTERTREATMENT VIA ACTIVE FLOW CONTROL

    SciTech Connect

    David K. Irick; Ke Nguyen

    2004-04-01

    The project is focused on the development of an energy efficient aftertreatment system capable of reducing NOx and methane by 90% from lean-burn natural gas engines by applying active exhaust flow control. Compared to conventional passive flow-through reactors, the proposed scheme cuts supplemental energy by 50%-70%. The system consists of a Lean NOx Trap (LNT) system and an oxidation catalyst. Through alternating flow control, a major amount of engine exhaust flows through a large portion of the LNT system in the absorption mode, while a small amount of exhaust goes through a small portion of the LNT system in the regeneration or desulfurization mode. By periodically reversing the exhaust gas flow through the oxidation catalyst, a higher temperature profile is maintained in the catalyst bed resulting in greater efficiency of the oxidation catalyst at lower exhaust temperatures. The project involves conceptual design, theoretical analysis, computer simulation, prototype fabrication, and empirical studies. This report details the progress during the first twelve months of the project. The primary activities have been to develop the bench flow reactor system, develop the computer simulation and modeling of the reverse-flow oxidation catalyst, install the engine into the test cell, and begin design of the LNT system.

  5. Energy Efficient Thermal Management for Natural Gas Engine Aftertreatment via Active Flow Control

    SciTech Connect

    David K. Irick; Ke Nguyen; Vitacheslav Naoumov; Doug Ferguson

    2006-04-01

    The project is focused on the development of an energy efficient aftertreatment system capable of reducing NOx and methane by 90% from lean-burn natural gas engines by applying active exhaust flow control. Compared to conventional passive flow-through reactors, the proposed scheme cuts supplemental energy by 50%-70%. The system consists of a Lean NOx Trap (LNT) system and an oxidation catalyst. Through alternating flow control, a major amount of engine exhaust flows through a large portion of the LNT system in the absorption mode, while a small amount of exhaust goes through a small portion of the LNT system in the regeneration or desulfurization mode. By periodically reversing the exhaust gas flow through the oxidation catalyst, a higher temperature profile is maintained in the catalyst bed resulting in greater efficiency of the oxidation catalyst at lower exhaust temperatures. The project involves conceptual design, theoretical analysis, computer simulation, prototype fabrication, and empirical studies. This report details the progress during the first twelve months of the project. The primary activities have been to develop the bench flow reactor system, develop the computer simulation and modeling of the reverse-flow oxidation catalyst, install the engine into the test cell, and begin design of the LNT system.

  6. An efficient computational scheme for electronic excitation spectra of molecules in solution using the symmetry-adapted cluster–configuration interaction method: The accuracy of excitation energies and intuitive charge-transfer indices

    SciTech Connect

    Fukuda, Ryoichi Ehara, Masahiro

    2014-10-21

    Solvent effects on electronic excitation spectra are considerable in many situations; therefore, we propose an efficient and reliable computational scheme that is based on the symmetry-adapted cluster-configuration interaction (SAC-CI) method and the polarizable continuum model (PCM) for describing electronic excitations in solution. The new scheme combines the recently proposed first-order PCM SAC-CI method with the PTE (perturbation theory at the energy level) PCM SAC scheme. This is essentially equivalent to the usual SAC and SAC-CI computations with using the PCM Hartree-Fock orbital and integrals, except for the additional correction terms that represent solute-solvent interactions. The test calculations demonstrate that the present method is a very good approximation of the more costly iterative PCM SAC-CI method for excitation energies of closed-shell molecules in their equilibrium geometry. This method provides very accurate values of electric dipole moments but is insufficient for describing the charge-transfer (CT) indices in polar solvent. The present method accurately reproduces the absorption spectra and their solvatochromism of push-pull type 2,2{sup ′}-bithiophene molecules. Significant solvent and substituent effects on these molecules are intuitively visualized using the CT indices. The present method is the simplest and theoretically consistent extension of SAC-CI method for including PCM environment, and therefore, it is useful for theoretical and computational spectroscopy.

  7. On the role of budget sufficiency, cost efficiency, and uncertainty in species management

    USGS Publications Warehouse

    van der Burg, Max Post; Bly, Bartholomew B.; Vercauteren, Tammy; Grand, James B.; Tyre, Andrew J.

    2014-01-01

    Many conservation planning frameworks rely on the assumption that one should prioritize locations for management actions based on the highest predicted conservation value (i.e., abundance, occupancy). This strategy may underperform relative to the expected outcome if one is working with a limited budget or the predicted responses are uncertain. Yet, cost and tolerance to uncertainty rarely become part of species management plans. We used field data and predictive models to simulate a decision problem involving western burrowing owls (Athene cunicularia hypugaea) using prairie dog colonies (Cynomys ludovicianus) in western Nebraska. We considered 2 species management strategies: one maximized abundance and the other maximized abundance in a cost-efficient way. We then used heuristic decision algorithms to compare the 2 strategies in terms of how well they met a hypothetical conservation objective. Finally, we performed an info-gap decision analysis to determine how these strategies performed under different budget constraints and uncertainty about owl response. Our results suggested that when budgets were sufficient to manage all sites, the maximizing strategy was optimal and suggested investing more in expensive actions. This pattern persisted for restricted budgets up to approximately 50% of the sufficient budget. Below this budget, the cost-efficient strategy was optimal and suggested investing in cheaper actions. When uncertainty in the expected responses was introduced, the strategy that maximized abundance remained robust under a sufficient budget. Reducing the budget induced a slight trade-off between expected performance and robustness, which suggested that the most robust strategy depended both on one's budget and tolerance to uncertainty. Our results suggest that wildlife managers should explicitly account for budget limitations and be realistic about their expected levels of performance.

  8. Classification schemes for arteriovenous malformations.

    PubMed

    Davies, Jason M; Kim, Helen; Young, William L; Lawton, Michael T

    2012-01-01

    The wide variety of arteriovenous malformation (AVM) anatomy, size, location, and clinical presentation makes patient selection for surgery a difficult process. Neurosurgeons have identified key factors that determine the risks of surgery and then devised classification schemes that integrate these factors, predict surgical results, and help select patients for surgery. These classification schemes have value because they transform complex decisions into simpler algorithms. In this review, the important grading schemes that have contributed to management of patients with brain AVMs are described, and our current approach to patient selection is outlined.

  9. An efficient simulation-optimization coupling for management of coastal aquifers

    NASA Astrophysics Data System (ADS)

    Kourakos, George; Mantoglou, Aristotelis

    2015-09-01

    Seawater intrusion in coastal aquifers is a major environmental problem and efficient tools are needed to assist decision making. Decision tools are often simulation models (which evaluate probable actions) combined with optimization algorithms (which search for optimum management decisions). A coupling between simulation models and optimization algorithms for management of coastal aquifers is presented. The simulation models are based on the sharp-interface approximation where the decision variables do not affect the discretized system matrix. For such problems, a transformation of the system matrix prior to optimization is proposed which supports rapid solution of the linear system of equations during the optimization stage, for different values of decision variables. The method is applied to a hypothetical simulation of a coastal aquifer on the Greek island of Santorini, where the proposed simulation-optimization coupling method is employed to maximize pumping rates subject to environmental constraints that protect the aquifer from seawater intrusion. Various packages were tested in order to investigate their efficiency in solving the linear system pertinent to the case study. The proposed method, based on coupling of equations, is found to be very efficient in terms of computational cost. In particular, for the problem examined, it is at least 50 times faster than standard methods, depending on the grid size.

  10. Mediator-free direct Z-scheme photocatalytic system: BiVO4/g-C3N4 organic-inorganic hybrid photocatalyst with highly efficient visible-light-induced photocatalytic activity.

    PubMed

    Tian, Na; Huang, Hongwei; He, Ying; Guo, Yuxi; Zhang, Tierui; Zhang, Yihe

    2015-03-01

    We disclose the fabrication of a mediator-free direct Z-scheme photocatalyst system BiVO4/g-C3N4 using a mixed-calcination method based on the more reliable interfacial interaction. The facet coupling occurred between the g-C3N4 (002) and BiVO4 (121), and it was revealed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and transmission electron microscope (TEM). The crystal structure and optical properties of the as-prepared samples have also been characterized by Fourier-transform infrared (FTIR), scanning electron microscopy (SEM) and UV-vis diffuse reflectance spectra (DRS) in details. The photocatalytic experiments indicated that the BiVO4/g-C3N4 composite photocatalysts display a significantly enhanced photocatalytic activity pertaining to RhB degradation and photocurrent generation (PC) compared to the pristine BiVO4 and g-C3N4. This remarkably improved photocatalytic performance should be attributed to the fabrication of a direct Z-scheme system of BiVO4/g-C3N4, which can result in a more efficient separation of photoinduced charge carriers than band-band transfer, thus endowing it with the much more powerful oxidation and reduction capability, as confirmed by the photoluminescence (PL) spectra and electrochemical impedance spectra (EIS). The Z-scheme mechanism of BiVO4/g-C3N4 heterostructure was verified by a series of combined techniques, including the active species trapping experiments, NBT transformation and terephthalic acid photoluminescence probing technique (TA-PL) over BiVO4/g-C3N4 composites and the pristine samples. The present work not only furthered the understanding of mediator-free Z-scheme photocatalysis, but also shed new light on the design of heterostructural photocatalysts with high-performance. PMID:25635354

  11. Mediator-free direct Z-scheme photocatalytic system: BiVO4/g-C3N4 organic-inorganic hybrid photocatalyst with highly efficient visible-light-induced photocatalytic activity.

    PubMed

    Tian, Na; Huang, Hongwei; He, Ying; Guo, Yuxi; Zhang, Tierui; Zhang, Yihe

    2015-03-01

    We disclose the fabrication of a mediator-free direct Z-scheme photocatalyst system BiVO4/g-C3N4 using a mixed-calcination method based on the more reliable interfacial interaction. The facet coupling occurred between the g-C3N4 (002) and BiVO4 (121), and it was revealed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and transmission electron microscope (TEM). The crystal structure and optical properties of the as-prepared samples have also been characterized by Fourier-transform infrared (FTIR), scanning electron microscopy (SEM) and UV-vis diffuse reflectance spectra (DRS) in details. The photocatalytic experiments indicated that the BiVO4/g-C3N4 composite photocatalysts display a significantly enhanced photocatalytic activity pertaining to RhB degradation and photocurrent generation (PC) compared to the pristine BiVO4 and g-C3N4. This remarkably improved photocatalytic performance should be attributed to the fabrication of a direct Z-scheme system of BiVO4/g-C3N4, which can result in a more efficient separation of photoinduced charge carriers than band-band transfer, thus endowing it with the much more powerful oxidation and reduction capability, as confirmed by the photoluminescence (PL) spectra and electrochemical impedance spectra (EIS). The Z-scheme mechanism of BiVO4/g-C3N4 heterostructure was verified by a series of combined techniques, including the active species trapping experiments, NBT transformation and terephthalic acid photoluminescence probing technique (TA-PL) over BiVO4/g-C3N4 composites and the pristine samples. The present work not only furthered the understanding of mediator-free Z-scheme photocatalysis, but also shed new light on the design of heterostructural photocatalysts with high-performance.

  12. Methane emissions of beef cattle on forages: efficiency of grazing management systems.

    PubMed

    DeRamus, H Alan; Clement, Terry C; Giampola, Dean D; Dickison, Peter C

    2003-01-01

    Fermentation in the rumen of cattle produces methane (CH4). Methane may play a role in global warming scenarios. The linking of grazing management strategies to more efficient beef production while reducing the CH4 emitted by beef cattle is important. The sulfur hexafluoride (SF6) tracer technique was used to determine the effects of best management practices (BMP) grazing compared with continuous grazing on CH4 production in several Louisiana forages during 1996-1998. Cows and heifers (Bos taurus) grazed common bermudagrass [Cynodon dactylon (L.) Pers.], bahiagrass (Paspalum notatum Flugge), and ryegrass (Lolium multiflorum Lam.) pastures and were wintered on bahiagrass hay with supplements of protein molasses blocks (PMB), cottonseed meal and corn (CSMC), urea and corn (URC), or limited ryegrass grazing (LRG). Daily CH4 emissions were between 89 and 180 g d(-1) for young growing heifers and 165 to 294 g d(-1) for mature Simbrah cows. Heifers on "ad lib" ryegrass in March and April produced only one-tenth the CH4 per kg of gain as heifers on LRG of 1 h. Using BMP significantly reduced the emission of CH4 per unit of animal weight gain. Management-intensive grazing (MIG) is a BMP that offers the potential for more efficient utilization of grazed forage crops via controlled rotational grazing and more efficient conversion of forage into meat and milk. Projected CH4 annual emissions in cows reflect a 22% reduction from BMP when compared with continuous grazing in this study. With the BMP application of MIG, less methane was produced per kilogram of beef gain.

  13. Methane emissions of beef cattle on forages: efficiency of grazing management systems.

    PubMed

    DeRamus, H Alan; Clement, Terry C; Giampola, Dean D; Dickison, Peter C

    2003-01-01

    Fermentation in the rumen of cattle produces methane (CH4). Methane may play a role in global warming scenarios. The linking of grazing management strategies to more efficient beef production while reducing the CH4 emitted by beef cattle is important. The sulfur hexafluoride (SF6) tracer technique was used to determine the effects of best management practices (BMP) grazing compared with continuous grazing on CH4 production in several Louisiana forages during 1996-1998. Cows and heifers (Bos taurus) grazed common bermudagrass [Cynodon dactylon (L.) Pers.], bahiagrass (Paspalum notatum Flugge), and ryegrass (Lolium multiflorum Lam.) pastures and were wintered on bahiagrass hay with supplements of protein molasses blocks (PMB), cottonseed meal and corn (CSMC), urea and corn (URC), or limited ryegrass grazing (LRG). Daily CH4 emissions were between 89 and 180 g d(-1) for young growing heifers and 165 to 294 g d(-1) for mature Simbrah cows. Heifers on "ad lib" ryegrass in March and April produced only one-tenth the CH4 per kg of gain as heifers on LRG of 1 h. Using BMP significantly reduced the emission of CH4 per unit of animal weight gain. Management-intensive grazing (MIG) is a BMP that offers the potential for more efficient utilization of grazed forage crops via controlled rotational grazing and more efficient conversion of forage into meat and milk. Projected CH4 annual emissions in cows reflect a 22% reduction from BMP when compared with continuous grazing in this study. With the BMP application of MIG, less methane was produced per kilogram of beef gain. PMID:12549566

  14. Efficiency of dairy farms participating and not participating in veterinary herd health management programs.

    PubMed

    Derks, Marjolein; Hogeveen, Henk; Kooistra, Sake R; van Werven, Tine; Tauer, Loren W

    2014-12-01

    This paper compares farm efficiencies between dairies who were participating in a veterinary herd health management (VHHM) program with dairies not participating in such a program, to determine whether participation has an association with farm efficiency. In 2011, 572 dairy farmers received a questionnaire concerning the participation and execution of a VHHM program on their farms. Data from the questionnaire were combined with farm accountancy data from 2008 through 2012 from farms that used calendar year accounting periods, and were analyzed using Stochastic Frontier Analysis (SFA). Two separate models were specified: model 1 was the basic stochastic frontier model (output: total revenue; input: feed costs, land costs, cattle costs, non-operational costs), without explanatory variables embedded into the efficiency component of the error term. Model 2 was an expansion of model 1 which included explanatory variables (number of FTE; total kg milk delivered; price of concentrate; milk per hectare; cows per FTE; nutritional yield per hectare) inserted into the efficiency component of the joint error term. Both models were estimated with the financial parameters expressed per 100 kg fat and protein corrected milk and per cow. Land costs, cattle costs, feed costs and non-operational costs were statistically significant and positive in all models (P<0.01). Frequency distributions of the efficiency scores for the VHHM dairies and the non-VHHM dairies were plotted in a kernel density plot, and differences were tested using the Kolmogorov-Smirnov two-sample test. VHHM dairies had higher total revenue per cow, but not per 100 kg milk. For all SFA models, the difference in distribution was not statistically different between VHHM dairies and non-VHHM dairies (P values 0.94, 0.35, 0.95 and 0.89 for the basic and complete model per 100 kg fat and protein corrected milk and per cow respectively). Therefore we conclude that with our data farm participation in VHHM is not related

  15. An Integrated Approach to Thermal Management of International Space Station Logistics Flights, Improving the Efficiency

    NASA Technical Reports Server (NTRS)

    Holladay, Jon; Day, Greg; Roberts, Barry; Leahy, Frank

    2003-01-01

    The efficiency of re-useable aerospace systems requires a focus on the total operations process rather than just orbital performance. For the Multi-Purpose Logistics Module this activity included special attention to terrestrial conditions both pre-launch and post-landing and how they inter-relate to the mission profile. Several of the efficiencies implemented for the MPLM Mission Engineering were NASA firsts and all served to improve the overall operations activities. This paper will provide an explanation of how various issues were addressed and the resulting solutions. Topics range from statistical analysis of over 30 years of atmospheric data at the launch and landing site to a new approach for operations with the Shuttle Carrier Aircraft. In each situation the goal was to "tune" the thermal management of the overall flight system for minimizing requirement risk while optimizing power and energy performance.

  16. Redundancy management for efficient fault recovery in NASA's distributed computing system

    NASA Technical Reports Server (NTRS)

    Malek, Miroslaw; Pandya, Mihir; Yau, Kitty

    1991-01-01

    The management of redundancy in computer systems was studied and guidelines were provided for the development of NASA's fault-tolerant distributed systems. Fault recovery and reconfiguration mechanisms were examined. A theoretical foundation was laid for redundancy management by efficient reconfiguration methods and algorithmic diversity. Algorithms were developed to optimize the resources for embedding of computational graphs of tasks in the system architecture and reconfiguration of these tasks after a failure has occurred. The computational structure represented by a path and the complete binary tree was considered and the mesh and hypercube architectures were targeted for their embeddings. The innovative concept of Hybrid Algorithm Technique was introduced. This new technique provides a mechanism for obtaining fault tolerance while exhibiting improved performance.

  17. Stress wave communication in concrete: II. Evaluation of low voltage concrete stress wave communications utilizing spectrally efficient modulation schemes with PZT transducers

    NASA Astrophysics Data System (ADS)

    Siu, Sam; Qing, Ji; Wang, Kun; Song, Gangbing; Ding, Zhi

    2014-12-01

    Piezoelectric materials, traditionally used for structural health monitoring, have recently been used to implement stress wave communications. Within a protective encasing we fabricate a smart aggregate which enables transmission and reception of modulated stress waves for digital communication within concrete. Our research focuses on building a high efficiency stress wave communication system and comparing the performance of phase shift keying (PSK) with quadrature amplitude modulation (QAM). Our experiments evaluate the performance of QPSK and 16QAM implemented with our stress wave communication system at a transmit voltage ranging from 32 dBV to 37 dBV. We also demonstrate the increase in spectral efficiency of 16QAM compared to QPSK.

  18. Bulk Data Movement for Climate Dataset: Efficient Data Transfer Management with Dynamic Transfer Adjustment

    SciTech Connect

    Sim, Alexander; Balman, Mehmet; Williams, Dean N.; Shoshani, Arie; Natarajan, Vijaya

    2010-07-16

    Many scientific applications and experiments, such as high energy and nuclear physics, astrophysics, climate observation and modeling, combustion, nano-scale material sciences, and computational biology, generate extreme volumes of data with a large number of files. These data sources are distributed among national and international data repositories, and are shared by large numbers of geographically distributed scientists. A large portion of data is frequently accessed, and a large volume of data is moved from one place to another for analysis and storage. One challenging issue in such efforts is the limited network capacity for moving large datasets to explore and manage. The Bulk Data Mover (BDM), a data transfer management tool in the Earth System Grid (ESG) community, has been managing the massive dataset transfers efficiently with the pre-configured transfer properties in the environment where the network bandwidth is limited. Dynamic transfer adjustment was studied to enhance the BDM to handle significant end-to-end performance changes in the dynamic network environment as well as to control the data transfers for the desired transfer performance. We describe the results from the BDM transfer management for the climate datasets. We also describe the transfer estimation model and results from the dynamic transfer adjustment.

  19. Diagnostic laboratory for bleeding disorders ensures efficient management of haemorrhagic disorders.

    PubMed

    Riddell, A; Chuansumrit, A; El-Ekiaby, M; Nair, S C

    2016-07-01

    Haemorrhagic disorders like Postpartum haemorrhage and Dengue haemorrhagic fever are life threatening and requires an active and efficient transfusion service that could provide the most appropriate blood product which could be effective in managing them. This would essentially require prompt identification of the coagulopathy so that the best available product can be given to the bleeding patient to correct the identified haemostatic defect which will help control the bleeding. This would only be possible if the transfusion service has a laboratory to correctly detect the haemostatic defect and that too with an accuracy and precision which is ensured by a good laboratory quality assurance practices. These same processes are necessary for the transfusion services to ensure the quality of the blood products manufactured by them and that it contains adequate amounts of haemostasis factors which will be good to be effective in the management of haemorrhagic disorders. These issues are discussed in detail individually in the management of postpartum haemorrhage and Dengue haemorrhagic fever including when these can help in the use of rFVIIa in Dengue haemorrhagic fever. The requirements to ensure good-quality blood products are made available for the management of these disorders and the same have also been described. PMID:27405683

  20. Eco-efficient waste glass recycling: Integrated waste management and green product development through LCA

    SciTech Connect

    Blengini, Gian Andrea; Busto, Mirko; Fantoni, Moris; Fino, Debora

    2012-05-15

    Highlights: Black-Right-Pointing-Pointer A new eco-efficient recycling route for post-consumer waste glass was implemented. Black-Right-Pointing-Pointer Integrated waste management and industrial production are crucial to green products. Black-Right-Pointing-Pointer Most of the waste glass rejects are sent back to the glass industry. Black-Right-Pointing-Pointer Recovered co-products give more environmental gains than does avoided landfill. Black-Right-Pointing-Pointer Energy intensive recycling must be limited to waste that cannot be closed-loop recycled. - Abstract: As part of the EU Life + NOVEDI project, a new eco-efficient recycling route has been implemented to maximise resources and energy recovery from post-consumer waste glass, through integrated waste management and industrial production. Life cycle assessment (LCA) has been used to identify engineering solutions to sustainability during the development of green building products. The new process and the related LCA are framed within a meaningful case of industrial symbiosis, where multiple waste streams are utilised in a multi-output industrial process. The input is a mix of rejected waste glass from conventional container glass recycling and waste special glass such as monitor glass, bulbs and glass fibres. The green building product is a recycled foam glass (RFG) to be used in high efficiency thermally insulating and lightweight concrete. The environmental gains have been contrasted against induced impacts and improvements have been proposed. Recovered co-products, such as glass fragments/powders, plastics and metals, correspond to environmental gains that are higher than those related to landfill avoidance, whereas the latter is cancelled due to increased transportation distances. In accordance to an eco-efficiency principle, it has been highlighted that recourse to highly energy intensive recycling should be limited to waste that cannot be closed-loop recycled.

  1. New LNG process scheme

    SciTech Connect

    Foglietta, J.H.

    1999-07-01

    A new LNG cycle has been developed for base load liquefaction facilities. This new design offers a different technical and economical solution comparing in efficiency with the classical technologies. The new LNG scheme could offer attractive business opportunities to oil and gas companies that are trying to find paths to monetize gas sources more effectively; particularly for remote or offshore locations where smaller scale LNG facilities might be applicable. This design offers also an alternative route to classic LNG projects, as well as alternative fuel sources. Conceived to offer simplicity and access to industry standard equipment, This design is a hybrid result of combining a standard refrigeration system and turboexpander technology.

  2. Pay scheme preferences and health policy objectives.

    PubMed

    Abelsen, Birgit

    2011-04-01

    This paper studies the preferences among healthcare workers towards pay schemes involving different levels of risk. It identifies which pay scheme individuals would prefer for themselves, and which they think is best in furthering health policy objectives. The paper adds, methodologically, a way of defining pay schemes that include different levels of risk. A questionnaire was mailed to a random sample of 1111 dentists. Respondents provided information about their current and preferred pay schemes, and indicated which pay scheme, in their opinion, would best further overall health policy objectives. A total of 504 dentists (45%) returned the questionnaire, and there was no indication of systematic non-response bias. All public dentists had a current pay scheme based on a fixed salary and the majority of individuals preferred a pay scheme with more income risk. Their preferred pay schemes coincided with the ones believed to further stabilise healthcare personnel. The predominant current pay scheme among private dentists was based solely on individual output, and the majority of respondents preferred this pay scheme. In addition, their preferred pay schemes coincided with the ones believed to further efficiency objectives. Both public and private dentists believed that pay schemes, furthering efficiency objectives, had to include more performance-related pay than the ones believed to further stability and quality objectives. PMID:20565995

  3. Measuring eco-efficiency of contaminated soil management at the regional level.

    PubMed

    Kielenniva, Nea; Antikainen, Riina; Sorvari, Jaana

    2012-10-30

    Eco-efficiency and sustainable development are the key environmental topics and goals for today's society that we should strive for in all activities, including contaminated soil management (CSM). However, particularly at the regional level, CSM is studied to a lesser extent from this perspective and practical means to monitor and assess sustainability or eco-efficiency are not widely available. This study aims to fill this gap by developing indicators to measure and monitor the development of regional eco-efficiency of CSM. The indicators can be used to support decision-making at the regional level since many CSM decisions, such as prioritisation of sites and the number of soil treatment and storing facilities, are made regionally. To start with, we surveyed the methods available for determining eco-efficiency and suitable indicators to monitor and measure the development of CSM regionally. We used life cycle analysis (LCA) and material flow analysis (MFA) to identify factors that the environmental indicators should cover, and also involved economic indicators. We ended up with a selection of 28 indicators, which can be classed into three different categories: background indicators, environmental indicators and economic indicators. We further demonstrated the use of the indicators by applying data from three different regions in Finland, and evaluated their suitability. On the basis of the results we recommended 15 indicators for continuous follow-up and decision-making purposes. Even though these indicators are suitable for monitoring and measuring the eco-efficiency of CSM at the regional level, unfortunately we found several data gaps related to the actual remediation projects which impede their use in practice. The data collection practices therefore need to be regionally developed.

  4. IoT-based smart garbage system for efficient food waste management.

    PubMed

    Hong, Insung; Park, Sunghoi; Lee, Beomseok; Lee, Jaekeun; Jeong, Daebeom; Park, Sehyun

    2014-01-01

    Owing to a paradigm shift toward Internet of Things (IoT), researches into IoT services have been conducted in a wide range of fields. As a major application field of IoT, waste management has become one such issue. The absence of efficient waste management has caused serious environmental problems and cost issues. Therefore, in this paper, an IoT-based smart garbage system (SGS) is proposed to reduce the amount of food waste. In an SGS, battery-based smart garbage bins (SGBs) exchange information with each other using wireless mesh networks, and a router and server collect and analyze the information for service provisioning. Furthermore, the SGS includes various IoT techniques considering user convenience and increases the battery lifetime through two types of energy-efficient operations of the SGBs: stand-alone operation and cooperation-based operation. The proposed SGS had been operated as a pilot project in Gangnam district, Seoul, Republic of Korea, for a one-year period. The experiment showed that the average amount of food waste could be reduced by 33%.

  5. IoT-Based Smart Garbage System for Efficient Food Waste Management

    PubMed Central

    Lee, Jaekeun

    2014-01-01

    Owing to a paradigm shift toward Internet of Things (IoT), researches into IoT services have been conducted in a wide range of fields. As a major application field of IoT, waste management has become one such issue. The absence of efficient waste management has caused serious environmental problems and cost issues. Therefore, in this paper, an IoT-based smart garbage system (SGS) is proposed to reduce the amount of food waste. In an SGS, battery-based smart garbage bins (SGBs) exchange information with each other using wireless mesh networks, and a router and server collect and analyze the information for service provisioning. Furthermore, the SGS includes various IoT techniques considering user convenience and increases the battery lifetime through two types of energy-efficient operations of the SGBs: stand-alone operation and cooperation-based operation. The proposed SGS had been operated as a pilot project in Gangnam district, Seoul, Republic of Korea, for a one-year period. The experiment showed that the average amount of food waste could be reduced by 33%. PMID:25258730

  6. Efficient Power Management for Energy-Autonomous Wireless Sensor Nodes for Aeronautical Applications

    NASA Astrophysics Data System (ADS)

    Elefsiniotis, A.; Weiss, M.; Becker, Th.; Schmid, U.

    2013-07-01

    Efficient power management is a key component for energy-autonomous wireless sensor nodes. Thermoelectric energy harvesting is a possible solution for powering such sensor nodes. In this paper, we present a power management circuit that has significant improvements compared with earlier versions. Advancements were made to the rectifier part and the storage controller. The improved rectification circuit is able to control the p-metal-oxide-semiconductor ( p-MOS) transistors with a negative instead of zero voltage at the gate. Furthermore, modifications to enhance the total efficiency of the storage controller are applied. The storage controller is a direct current (DC)-DC converter and is controlled by a pulse frequency modulation signal, provided by a microcontroller. In the modified version, the microcontroller is always in low-power mode, and an external circuit is used to control the storage controller. Changes in the software are applied so that the microcontroller is always set in low-power mode. The runtime with and without a load are compared, and the overall self-discharge time is evaluated.

  7. Improving energy efficiency via smart building energy management systems. A comparison with policy measures

    DOE PAGES

    Rocha, Paula; Siddiqui, Afzal; Stadler, Michael

    2014-12-09

    In this study, to foster the transition to more sustainable energy systems, policymakers have been approving measures to improve energy efficiency as well as promoting smart grids. In this setting, building managers are encouraged to adapt their energy operations to real-time market and weather conditions. Yet, most fail to do so as they rely on conventional building energy management systems (BEMS) that have static temperature set points for heating and cooling equipment. In this paper, we investigate how effective policy measures are at improving building-level energy efficiency compared to a smart BEMS with dynamic temperature set points. To this end,more » we present an integrated optimisation model mimicking the smart BEMS that combines decisions on heating and cooling systems operations with decisions on energy sourcing. Using data from an Austrian and a Spanish building, we find that the smart BEMS results in greater reduction in energy consumption than a conventional BEMS with policy measures.« less

  8. Water use efficiency and integrated water resource management for river basin

    NASA Astrophysics Data System (ADS)

    Deng, Xiangzheng; Singh, R. B.; Liu, Junguo; Güneralp, Burak

    Water use efficiency and management have attracted increasing attention as water has become scare to challenge the world's sustainable development. Water use efficiency is correlated to the land use and cover changes (LUCC), population distribution, industrial structure, economic development, climate changes, and environmental governance. These factors significantly alter water productivity for water balance through the changes in natural environment and socio-economic system (Wang et al., 2015b). Consequently, dynamics of water inefficiency lower the social welfare of water allocation (Wang et al., 2015b), and induce water management alternation interactively and financially (Wang et al., 2015a). This triggers on actual water price changes through both natural resource and socioeconomic system (Zhou et al., 2015). Therefore, it is very important to figure out a mechanism of water allocation in the course of LUCC (Jin et al., 2015) at a global perspective (Zhao et al., 2015), climate and economic changes of ecosystem service at various spatial and temporal scales (Li et al., 2015).

  9. IoT-based smart garbage system for efficient food waste management.

    PubMed

    Hong, Insung; Park, Sunghoi; Lee, Beomseok; Lee, Jaekeun; Jeong, Daebeom; Park, Sehyun

    2014-01-01

    Owing to a paradigm shift toward Internet of Things (IoT), researches into IoT services have been conducted in a wide range of fields. As a major application field of IoT, waste management has become one such issue. The absence of efficient waste management has caused serious environmental problems and cost issues. Therefore, in this paper, an IoT-based smart garbage system (SGS) is proposed to reduce the amount of food waste. In an SGS, battery-based smart garbage bins (SGBs) exchange information with each other using wireless mesh networks, and a router and server collect and analyze the information for service provisioning. Furthermore, the SGS includes various IoT techniques considering user convenience and increases the battery lifetime through two types of energy-efficient operations of the SGBs: stand-alone operation and cooperation-based operation. The proposed SGS had been operated as a pilot project in Gangnam district, Seoul, Republic of Korea, for a one-year period. The experiment showed that the average amount of food waste could be reduced by 33%. PMID:25258730

  10. An Efficient Simulation-Optimization Coupling for Management of Coastal Aquifers

    NASA Astrophysics Data System (ADS)

    Mantoglou, A.; Kourakos, G.

    2013-12-01

    Seawater intrusion is a major environmental problem and efficient tools are required to assist decision making. Decision tools are often comprised of simulation models which evaluate promising actions and optimization algorithms to search for optimum management solutions. In this work we present an efficient coupling between simulation models and optimization algorithms suitable for management of coastal aquifers based on the sharp interface approximation. Generally, the simulation models are described by partial differential equations (PDEs). The numerical solution of a PDE involves several steps. First the domain is discretized into a number of nodes. Next the partial differential equation is converted to a system of linear equations in the form AX=B by assembling the system matrix A and the vector B. The last step is the solution of the linear system AX=B. Typically the linear system is solved using Krylov subspace methods when the size of the problem is large or direct methods for relatively small problems. In both cases the solution of the linear system involves two distinct computations. In the case of iterative solvers a preconditioner of matrix A is first computed whereas in the case of direct methods the left hand side matrix A is first factorized (e.g. using LU factorization). The right hand side vector B is not used during this step and it is only required during the computation of the solution. Typically the most time consuming process is the preconditioning or factorization, while the solution time can be considered negligible. Therefore, for a system optimization of a linear problem, where the decision variables do not affect the system matrix A, we can transform the system matrix prior to optimization and then we can solve the system very rapidly for different right hand side vectors B, which depend on the decision variables. In this work we used the sharp interface approximation of Mantoglou (2004), which has the advantage that the non

  11. Certifying Industrial Energy Efficiency Performance: AligningManagement, Measurement, and Practice to Create Market Value

    SciTech Connect

    McKane, Aimee; Scheihing, Paul; Williams, Robert

    2007-07-01

    More than fifteen years after the launch of programs in theU.K. and U.S., industry still offers one of the largest opportunities forenergy savings worldwide. The International Energy Agency (IEA) estimatesthe savings potential from cost-optimization of industrial motor-drivensystems alone at 7 percent of global electricity use. The U.S. Departmentof Energy (USDOE) Industrial Technologies Program estimates 7 percentsavings potential in total US industrial energy use through theapplication of proven best practice. Simple paybacks for these types ofprojects are frequently two years or less. The technology required toachieve these savings is widely available; the technical skills requiredto identify energy saving opportunities are known and transferable.Although programs like USDOE's Best Practices have been highlysuccessful, most plants, as supported by 2002 MECS data, remain eitherunaware or unmotivated to improve their energy efficiency--as evidencedby the 98 percent of US industrial facilities reporting to MECS say thatthey lack a full-time energy manager. With the renewed interest in energyefficiency worldwide and the emergence of carbon trading and newfinancial instruments such as white certificates1, there is a need tointroduce greater transparency into the way that industrial facilitiesidentify, develop, and document energy efficiency projects. Historically,industrial energy efficiency projects have been developed by plantengineers, frequently with assistance from consultants and/or supplierswith highly specialized technical skills. Under this scenario,implementation of energy efficiency improvements is dependent onindividuals. These individuals typically include "champions" within anindustrial facility or corporation, working in cooperation withconsultants or suppliers who have substantial knowledge based on years ofexperience. This approach is not easily understood by others without thisspecialized technical knowledge, penetrates the market fairly slowly

  12. Eco-efficient waste glass recycling: Integrated waste management and green product development through LCA.

    PubMed

    Blengini, Gian Andrea; Busto, Mirko; Fantoni, Moris; Fino, Debora

    2012-05-01

    As part of the EU Life + NOVEDI project, a new eco-efficient recycling route has been implemented to maximise resources and energy recovery from post-consumer waste glass, through integrated waste management and industrial production. Life cycle assessment (LCA) has been used to identify engineering solutions to sustainability during the development of green building products. The new process and the related LCA are framed within a meaningful case of industrial symbiosis, where multiple waste streams are utilised in a multi-output industrial process. The input is a mix of rejected waste glass from conventional container glass recycling and waste special glass such as monitor glass, bulbs and glass fibres. The green building product is a recycled foam glass (RFG) to be used in high efficiency thermally insulating and lightweight concrete. The environmental gains have been contrasted against induced impacts and improvements have been proposed. Recovered co-products, such as glass fragments/powders, plastics and metals, correspond to environmental gains that are higher than those related to landfill avoidance, whereas the latter is cancelled due to increased transportation distances. In accordance to an eco-efficiency principle, it has been highlighted that recourse to highly energy intensive recycling should be limited to waste that cannot be closed-loop recycled. PMID:22093705

  13. Graduated punishment is efficient in resource management if people are heterogeneous.

    PubMed

    Iwasa, Yoh; Lee, Joung-Hun

    2013-09-21

    In natural resource managements, people often overcome tragedy of commons by developing an institution that punishes selfish actions, thus enhancing pro-social behavior. Elinor Ostrom reported that many successful communities apply graduated punishment--the punishment level gradually increases with the amount of harm of the selfish action. This observation is apparently in conflict with a theoretical study of public good game supporting a severe and strict punishment. Here, we study the conditions in which graduated punishment enforces cooperation most efficiently. If people follow a quantal response equilibrium, the optimal punishment is a jump from no punishment to a high level of punishment then increases little with the societal harm, which is inconsistent with the graduated punishment concept. We find that the graduated punishment is the most efficient rule if there is a small probability that player's action is reported incorrectly and if players are heterogeneous in their sensitivity to utility (or payoff) difference. We derive a mathematical formula for the optimal punishment when people's sensitivity to utility difference follows an exponential distribution. When the magnitude of harm is large, the optimal punishment increases in proportion to the square root of the societal harm, thus confirming the efficiency of the graduated punishment. PMID:23721682

  14. Eco-efficient waste glass recycling: Integrated waste management and green product development through LCA.

    PubMed

    Blengini, Gian Andrea; Busto, Mirko; Fantoni, Moris; Fino, Debora

    2012-05-01

    As part of the EU Life + NOVEDI project, a new eco-efficient recycling route has been implemented to maximise resources and energy recovery from post-consumer waste glass, through integrated waste management and industrial production. Life cycle assessment (LCA) has been used to identify engineering solutions to sustainability during the development of green building products. The new process and the related LCA are framed within a meaningful case of industrial symbiosis, where multiple waste streams are utilised in a multi-output industrial process. The input is a mix of rejected waste glass from conventional container glass recycling and waste special glass such as monitor glass, bulbs and glass fibres. The green building product is a recycled foam glass (RFG) to be used in high efficiency thermally insulating and lightweight concrete. The environmental gains have been contrasted against induced impacts and improvements have been proposed. Recovered co-products, such as glass fragments/powders, plastics and metals, correspond to environmental gains that are higher than those related to landfill avoidance, whereas the latter is cancelled due to increased transportation distances. In accordance to an eco-efficiency principle, it has been highlighted that recourse to highly energy intensive recycling should be limited to waste that cannot be closed-loop recycled.

  15. A flexible and efficient multi-model framework in support of water management

    NASA Astrophysics Data System (ADS)

    Wolfs, Vincent; Tran Quoc, Quan; Willems, Patrick

    2016-05-01

    Flexible, fast and accurate water quantity models are essential tools in support of water management. Adjustable levels of model detail and the ability to handle varying spatial and temporal resolutions are requisite model characteristics to ensure that such models can be employed efficiently in various applications. This paper uses a newly developed flexible modelling framework that aims to generate such models. The framework incorporates several approaches to model catchment hydrology, rivers and floodplains, and the urban drainage system by lumping processes on different levels. To illustrate this framework, a case study of integrated hydrological-hydraulic modelling is elaborated for the Grote Nete catchment in Belgium. Three conceptual rainfall-runoff models (NAM, PDM and VHM) were implemented in a generalized model structure, allowing flexibility in the spatial resolution by means of an innovative disaggregation/aggregation procedure. They were linked to conceptual hydraulic models of the rivers in the catchment, which were developed by means of an advanced model structure identification and calibration procedure. The conceptual models manage to emulate the simulation results of a detailed full hydrodynamic model accurately. The models configured using the approaches of this framework are well-suited for many applications in water management due to their very short calculation time, interfacing possibilities and adjustable level of detail.

  16. Graphene-Based Hybrid Composites for Efficient Thermal Management of Electronic Devices.

    PubMed

    Shtein, Michael; Nadiv, Roey; Buzaglo, Matat; Regev, Oren

    2015-10-28

    Thermal management has become a critical aspect in next-generation miniaturized electronic devices. Efficient heat dissipation reduces their operating temperatures and insures optimal performance, service life, and efficacy. Shielding against shocks, vibrations, and moisture is also imperative when the electronic circuits are located outdoors. Potting (or encapsulating) them in polymer-based composites with enhanced thermal conductivity (TC) may provide a solution for both thermal management and shielding challenges. In the current study, graphene is employed as a filler to fabricate composites with isotropic ultrahigh TC (>12 W m(-1) K(-1)) and good mechanical properties (>30 MPa flexural and compressive strength). To avoid short-circuiting the electronic assemblies, a dispersion of secondary ceramic-based filler reduces the electrical conductivity and synergistically enhances the TC of composites. When utilized as potting materials, these novel hybrid composites effectively dissipate the heat from electronic devices; their operating temperatures decrease from 110 to 37 °C, and their effective thermal resistances are drastically reduced, by up to 90%. The simple filler dispersion method and the precise manipulation of the composite transport properties via hybrid filling offer a universal approach to the large-scale production of novel materials for thermal management and other applications. PMID:26445279

  17. Multiscale Free Energy Simulations: An Efficient Method for Connecting Classical MD Simulations to QM or QM/MM Free Energies Using Non-Boltzmann Bennett Reweighting Schemes.

    PubMed

    König, Gerhard; Hudson, Phillip S; Boresch, Stefan; Woodcock, H Lee

    2014-04-01

    THE RELIABILITY OF FREE ENERGY SIMULATIONS (FES) IS LIMITED BY TWO FACTORS: (a) the need for correct sampling and (b) the accuracy of the computational method employed. Classical methods (e.g., force fields) are typically used for FES and present a myriad of challenges, with parametrization being a principle one. On the other hand, parameter-free quantum mechanical (QM) methods tend to be too computationally expensive for adequate sampling. One widely used approach is a combination of methods, where the free energy difference between the two end states is computed by, e.g., molecular mechanics (MM), and the end states are corrected by more accurate methods, such as QM or hybrid QM/MM techniques. Here we report two new approaches that significantly improve the aforementioned scheme; with a focus on how to compute corrections between, e.g., the MM and the more accurate QM calculations. First, a molecular dynamics trajectory that properly samples relevant conformational degrees of freedom is generated. Next, potential energies of each trajectory frame are generated with a QM or QM/MM Hamiltonian. Free energy differences are then calculated based on the QM or QM/MM energies using either a non-Boltzmann Bennett approach (QM-NBB) or non-Boltzmann free energy perturbation (NB-FEP). Both approaches are applied to calculate relative and absolute solvation free energies in explicit and implicit solvent environments. Solvation free energy differences (relative and absolute) between ethane and methanol in explicit solvent are used as the initial test case for QM-NBB. Next, implicit solvent methods are employed in conjunction with both QM-NBB and NB-FEP to compute absolute solvation free energies for 21 compounds. These compounds range from small molecules such as ethane and methanol to fairly large, flexible solutes, such as triacetyl glycerol. Several technical aspects were investigated. Ultimately some best practices are suggested for improving methods that seek to connect

  18. Matroids and quantum-secret-sharing schemes

    SciTech Connect

    Sarvepalli, Pradeep; Raussendorf, Robert

    2010-05-15

    A secret-sharing scheme is a cryptographic protocol to distribute a secret state in an encoded form among a group of players such that only authorized subsets of the players can reconstruct the secret. Classically, efficient secret-sharing schemes have been shown to be induced by matroids. Furthermore, access structures of such schemes can be characterized by an excluded minor relation. No such relations are known for quantum secret-sharing schemes. In this paper we take the first steps toward a matroidal characterization of quantum-secret-sharing schemes. In addition to providing a new perspective on quantum-secret-sharing schemes, this characterization has important benefits. While previous work has shown how to construct quantum-secret-sharing schemes for general access structures, these schemes are not claimed to be efficient. In this context the present results prove to be useful; they enable us to construct efficient quantum-secret-sharing schemes for many general access structures. More precisely, we show that an identically self-dual matroid that is representable over a finite field induces a pure-state quantum-secret-sharing scheme with information rate 1.

  19. Irrigation management strategies to improve Water Use Efficiency of potatoes crop in Central Tunisia

    NASA Astrophysics Data System (ADS)

    Ghazouani, Hiba; Provenzano, Giuseppe; Rallo, Giovanni; Mguidiche, Amel; Douh, Boutheina; Boujelben, Abdelhamid

    2015-04-01

    In Tunisia, the expansion of irrigated area and the semiarid climate make it compulsory to adopt strategies of water management to increase water use efficiency. Subsurface drip irrigation (SDI), providing the application of high frequency small irrigation volumes below the soil surface have been increasingly used to enhance irrigation efficiency. At the same time, deficit irrigation (DI) has shown successful results with a large number of crop in various countries. However, for some crops like potatoes, DI is difficult to manage due to the rapid effect of water stress on tuber yield. Irrigation frequency is a key factor to schedule subsurface drip irrigation because, even maintaining the total seasonal volume, soil wetting patterns can result different during the growth period, with consequence on crop yield. Despite the need to enhance water use efficiency, only a few studies related to deficit irrigation of horticultural crops have been made in Tunisia. Objective of the paper was to assess the effects of different on-farm irrigation strategies on water use efficiency of potatoes crop irrigated with subsurface drip irrigation in a semiarid area of central Tunisia. After validation, Hydrus-2D model was used to simulate soil water status in the root zone, to evaluate actual crop evapotranspiration and then to estimate indirectly water use efficiency (IWUE), defined as the ratio between crop yield and total amount of water supplied with irrigation. Field experiments, were carried out in Central Tunisia (10° 33' 47.0" E, 35° 58' 8.1° N, 19 m a.s.l) on a potatoes crop planted in a sandy loam soil, during the growing season 2014, from January 15 (plantation of tubers) to May 6 (harvesting). Soil water status was monitored in two plots (T1 and T2) maintained under the same management, but different irrigation volumes, provided by a SDI system. In particular, irrigation was scheduled according to the average water content measured in the root zone, with a total of 8

  20. Operating room data management: improving efficiency and safety in a surgical block

    PubMed Central

    2013-01-01

    Background European Healthcare Systems are facing a difficult period characterized by increasing costs and spending cuts due to economic problems. There is the urgent need for new tools which sustain Hospitals decision makers work. This project aimed to develop a data recording system of the surgical process of every patient within the operating theatre. The primary goal was to create a practical and easy data processing tool to give hospital managers, anesthesiologists and surgeons the information basis to increase operating theaters efficiency and patient safety. Methods The developed data analysis tool is embedded in an Oracle Business Intelligence Environment, which processes data to simple and understandable performance tachometers and tables. The underlying data analysis is based on scientific literature and the projects teams experience with tracked data. The system login is layered and different users have access to different data outputs depending on their professional needs. The system is divided in the tree profile types Manager, Anesthesiologist and Surgeon. Every profile includes subcategories where operators can access more detailed data analyses. The first data output screen shows general information and guides the user towards more detailed data analysis. The data recording system enabled the registration of 14.675 surgical operations performed from 2009 to 2011. Results Raw utilization increased from 44% in 2009 to 52% in 2011. The number of high complexity surgical procedures (≥120 minutes) has increased in certain units while decreased in others. The number of unscheduled procedures performed has been reduced (from 25% in 2009 to 14% in 2011) while maintaining the same percentage of surgical procedures. The number of overtime events decreased in 2010 (23%) and in 2011 (21%) compared to 2009 (28%) and the delays expressed in minutes are almost the same (mean 78 min). The direct link found between the complexity of surgical procedures, the number

  1. Implementation of efficient irrigation management for a sustainable agriculture. LIFE+ project IRRIMAN

    NASA Astrophysics Data System (ADS)

    Pérez-Pastor, Alejandro; Garcia-Vila, Margarita; Gamero-Ojeda, Pedro; Ascensión Carmona, M.°; Hernandez, David; José Alarcón, Juan; Nicolás, Emilio; Nortes, Pedro; Aroca, Antonio; María de la Rosa, Jose; Zornoza, Raúl; Faz, Ángel; Molina, Angel; Torres, Roque; Ruiz, Manuel; Calatrava, Javier

    2016-04-01

    In water scarcity areas, it must be highlighted that the maximum productions of the crops do not necessarily imply maximum profitability. Therefore, during the last years a special interest in the development of deficit irrigation strategies based on significant reductions of the seasonal ET without affecting production or quality has been observed. The strategies of regulated deficit irrigation (RDI) are based on the reduction of water supply during non critical periods, the covering of water needs during critical periods and maximizing, at the same time, the production by unit of applied water. But its success greatly depends on the adequate application of the water deficit and requires a continuous and precise control of the plant and soil water status to adjust the water supplies at every crop phenological period. The main objective of this project is to implement, demonstrate and disseminate a sustainable irrigation strategy based on deficit irrigation to promote its large scale acceptance and use in woody crops in Mediterranean agroecosystems, characterized by water scarcity, without affecting the quality standards demanded by exportation markets. With the adoption of this irrigation management we mean to ensure efficient use of water resources, improving quantitative water management, preserving high level of water quality and avoiding misuse and deterioration of water resources. The adoption of efficient irrigation will also lead to increments in water productivity, increments in the potential carbon fixation of the agroecosystem, and decrease energy costs of pressurized irrigation, together with mitigation and adaptation to climate change. The project will achieve the general objective by implication of farmers, irrigation communities, agronomists, industry, consultants, associations and public administration, by increments in social awareness for sustainable irrigation benefits, optimization of irrigation scheduling, improvements in technology, and

  2. Efficient Fiber Bragg Grating and Fiber Fabry-Pérot Sensor Multiplexing Scheme Using a Broadband Pulsed Mode-Locked Laser

    NASA Astrophysics Data System (ADS)

    Cranch, Geoffrey A.; Flockhart, Gordon M. H.; Kirkendall, Clay K.

    2005-11-01

    A pulsed broadband mode-locked laser (MLL) combined with interferometric interrogation is shown to yield an efficient means of multiplexing a large number of fiber Bragg grating (FBG) or fiber Fabry-Pérot (FFP) strain sensors with high performance. System configurations utilizing time division multiplexing (TDM) permit high resolution, accuracy, and bandwidth strain measurements along with high sensor densities. Strain resolutions of 23-60 n_varepsilon/Hz1/2 at frequencies up to 800 Hz (expandable to 139 kHz) and a differential strain-measurement accuracy of +/-1?;_varepsilon are demonstrated. Interrogation of a low-finesse FFP sensor is also demonstrated, from which a strain resolution of 2n_varepsilon/Hz1/2 and strain-measurement accuracy of +/-31n_varepsilon are achieved. The system has the capability of interrogating well in excess of 50 sensors per fiber depending on crosstalk requirements. A discussion on sensor spacing, bandwidth, dynamic range, and measurement accuracy is also given.

  3. Predictors associated with an efficient health information management in patients with cardiac surgery.

    PubMed

    Lee, Seong-Ran

    2014-01-01

    Because of the increasing number of cardiac patients all over the world, the importance of cardiac disease prevention is increasing. This study was attempted to identify the predictors associated with an efficient health information patients in two general hospitals located in Seoul from May 13 to June 13, 2012. The results were as follows: First, analysis of the percentage of nutrient intake in terms of meal pattern showed that the response rate of 47.9% in the case group at vegetable intake of 2 or 3 times per week was significantly higher than the response rate of 47.1% in the control group (X^{2}=9.08, p< 0.05), Second, the multiple logistic regression analysis revealed that efficiency of a health information management was significantly associated with female (OR=3.24, 95% Cl: 1.93-6.84), the subjects having abdominal obesity (OR=2.29, 95% Cl: 1.15-3.60). Therefore, the proposed framework will be helpful for health information system developers.

  4. Nonlinear secret image sharing scheme.

    PubMed

    Shin, Sang-Ho; Lee, Gil-Je; Yoo, Kee-Young

    2014-01-01

    Over the past decade, most of secret image sharing schemes have been proposed by using Shamir's technique. It is based on a linear combination polynomial arithmetic. Although Shamir's technique based secret image sharing schemes are efficient and scalable for various environments, there exists a security threat such as Tompa-Woll attack. Renvall and Ding proposed a new secret sharing technique based on nonlinear combination polynomial arithmetic in order to solve this threat. It is hard to apply to the secret image sharing. In this paper, we propose a (t, n)-threshold nonlinear secret image sharing scheme with steganography concept. In order to achieve a suitable and secure secret image sharing scheme, we adapt a modified LSB embedding technique with XOR Boolean algebra operation, define a new variable m, and change a range of prime p in sharing procedure. In order to evaluate efficiency and security of proposed scheme, we use the embedding capacity and PSNR. As a result of it, average value of PSNR and embedding capacity are 44.78 (dB) and 1.74t⌈log2 m⌉ bit-per-pixel (bpp), respectively.

  5. Nonlinear secret image sharing scheme.

    PubMed

    Shin, Sang-Ho; Lee, Gil-Je; Yoo, Kee-Young

    2014-01-01

    Over the past decade, most of secret image sharing schemes have been proposed by using Shamir's technique. It is based on a linear combination polynomial arithmetic. Although Shamir's technique based secret image sharing schemes are efficient and scalable for various environments, there exists a security threat such as Tompa-Woll attack. Renvall and Ding proposed a new secret sharing technique based on nonlinear combination polynomial arithmetic in order to solve this threat. It is hard to apply to the secret image sharing. In this paper, we propose a (t, n)-threshold nonlinear secret image sharing scheme with steganography concept. In order to achieve a suitable and secure secret image sharing scheme, we adapt a modified LSB embedding technique with XOR Boolean algebra operation, define a new variable m, and change a range of prime p in sharing procedure. In order to evaluate efficiency and security of proposed scheme, we use the embedding capacity and PSNR. As a result of it, average value of PSNR and embedding capacity are 44.78 (dB) and 1.74t⌈log2 m⌉ bit-per-pixel (bpp), respectively. PMID:25140334

  6. Nonlinear Secret Image Sharing Scheme

    PubMed Central

    Shin, Sang-Ho; Yoo, Kee-Young

    2014-01-01

    Over the past decade, most of secret image sharing schemes have been proposed by using Shamir's technique. It is based on a linear combination polynomial arithmetic. Although Shamir's technique based secret image sharing schemes are efficient and scalable for various environments, there exists a security threat such as Tompa-Woll attack. Renvall and Ding proposed a new secret sharing technique based on nonlinear combination polynomial arithmetic in order to solve this threat. It is hard to apply to the secret image sharing. In this paper, we propose a (t, n)-threshold nonlinear secret image sharing scheme with steganography concept. In order to achieve a suitable and secure secret image sharing scheme, we adapt a modified LSB embedding technique with XOR Boolean algebra operation, define a new variable m, and change a range of prime p in sharing procedure. In order to evaluate efficiency and security of proposed scheme, we use the embedding capacity and PSNR. As a result of it, average value of PSNR and embedding capacity are 44.78 (dB) and 1.74t⌈log2⁡m⌉ bit-per-pixel (bpp), respectively. PMID:25140334

  7. Extending DIRAC File Management with Erasure-Coding for efficient storage.

    NASA Astrophysics Data System (ADS)

    Cadellin Skipsey, Samuel; Todev, Paulin; Britton, David; Crooks, David; Roy, Gareth

    2015-12-01

    The state of the art in Grid style data management is to achieve increased resilience of data via multiple complete replicas of data files across multiple storage endpoints. While this is effective, it is not the most space-efficient approach to resilience, especially when the reliability of individual storage endpoints is sufficiently high that only a few will be inactive at any point in time. We report on work performed as part of GridPP[1], extending the Dirac File Catalogue and file management interface to allow the placement of erasure-coded files: each file distributed as N identically-sized chunks of data striped across a vector of storage endpoints, encoded such that any M chunks can be lost and the original file can be reconstructed. The tools developed are transparent to the user, and, as well as allowing up and downloading of data to Grid storage, also provide the possibility of parallelising access across all of the distributed chunks at once, improving data transfer and IO performance. We expect this approach to be of most interest to smaller VOs, who have tighter bounds on the storage available to them, but larger (WLCG) VOs may be interested as their total data increases during Run 2. We provide an analysis of the costs and benefits of the approach, along with future development and implementation plans in this area. In general, overheads for multiple file transfers provide the largest issue for competitiveness of this approach at present.

  8. Abatement vs. treatment for efficient diffuse source water pollution management in terrestrial-marine systems.

    PubMed

    Roebeling, P C; Cunha, M C; Arroja, L; van Grieken, M E

    2015-01-01

    Marine ecosystems are affected by water pollution originating from coastal catchments. The delivery of water pollutants can be reduced through water pollution abatement as well as water pollution treatment. Hence, sustainable economic development of coastal regions requires balancing of the marginal costs from water pollution abatement and/or treatment and the associated marginal benefits from marine resource appreciation. Water pollution delivery reduction costs are, however, not equal across abatement and treatment options. In this paper, an optimal control approach is developed and applied to explore welfare maximizing rates of water pollution abatement and/or treatment for efficient diffuse source water pollution management in terrestrial-marine systems. For the case of diffuse source dissolved inorganic nitrogen water pollution in the Tully-Murray region, Queensland, Australia, (agricultural) water pollution abatement cost, (wetland) water pollution treatment cost and marine benefit functions are determined to explore welfare maximizing rates of water pollution abatement and/or treatment. Considering partial (wetland) treatment costs and positive water quality improvement benefits, results show that welfare gains can be obtained, primarily, through diffuse source water pollution abatement (improved agricultural management practices) and, to a minor extent, through diffuse source water pollution treatment (wetland restoration). PMID:26287831

  9. TogoDoc Server/Client System: Smart Recommendation and Efficient Management of Life Science Literature

    PubMed Central

    Takagi, Toshihisa

    2010-01-01

    In this paper, we describe a server/client literature management system specialized for the life science domain, the TogoDoc system (Togo, pronounced Toe-Go, is a romanization of a Japanese word for integration). The server and the client program cooperate closely over the Internet to provide life scientists with an effective literature recommendation service and efficient literature management. The content-based and personalized literature recommendation helps researchers to isolate interesting papers from the “tsunami” of literature, in which, on average, more than one biomedical paper is added to MEDLINE every minute. Because researchers these days need to cover updates of much wider topics to generate hypotheses using massive datasets obtained from public databases or omics experiments, the importance of having an effective literature recommendation service is rising. The automatic recommendation is based on the content of personal literature libraries of electronic PDF papers. The client program automatically analyzes these files, which are sometimes deeply buried in storage disks of researchers' personal computers. Just saving PDF papers to the designated folders makes the client program automatically analyze and retrieve metadata, rename file names, synchronize the data to the server, and receive the recommendation lists of newly published papers, thus accomplishing effortless literature management. In addition, the tag suggestion and associative search functions are provided for easy classification of and access to past papers (researchers who read many papers sometimes only vaguely remember or completely forget what they read in the past). The TogoDoc system is available for both Windows and Mac OS X and is free. The TogoDoc Client software is available at http://tdc.cb.k.u-tokyo.ac.jp/, and the TogoDoc server is available at https://docman.dbcls.jp/pubmed_recom. PMID:21179453

  10. TogoDoc server/client system: smart recommendation and efficient management of life science literature.

    PubMed

    Iwasaki, Wataru; Yamamoto, Yasunori; Takagi, Toshihisa

    2010-12-13

    In this paper, we describe a server/client literature management system specialized for the life science domain, the TogoDoc system (Togo, pronounced Toe-Go, is a romanization of a Japanese word for integration). The server and the client program cooperate closely over the Internet to provide life scientists with an effective literature recommendation service and efficient literature management. The content-based and personalized literature recommendation helps researchers to isolate interesting papers from the "tsunami" of literature, in which, on average, more than one biomedical paper is added to MEDLINE every minute. Because researchers these days need to cover updates of much wider topics to generate hypotheses using massive datasets obtained from public databases or omics experiments, the importance of having an effective literature recommendation service is rising. The automatic recommendation is based on the content of personal literature libraries of electronic PDF papers. The client program automatically analyzes these files, which are sometimes deeply buried in storage disks of researchers' personal computers. Just saving PDF papers to the designated folders makes the client program automatically analyze and retrieve metadata, rename file names, synchronize the data to the server, and receive the recommendation lists of newly published papers, thus accomplishing effortless literature management. In addition, the tag suggestion and associative search functions are provided for easy classification of and access to past papers (researchers who read many papers sometimes only vaguely remember or completely forget what they read in the past). The TogoDoc system is available for both Windows and Mac OS X and is free. The TogoDoc Client software is available at http://tdc.cb.k.u-tokyo.ac.jp/, and the TogoDoc server is available at https://docman.dbcls.jp/pubmed_recom.

  11. [Management problems of improving the quality and efficiency of primary health care system of Georgia].

    PubMed

    Dzhakeli, I V; Edzhibadze, O I; Gerzmava, O Kh

    2009-01-01

    Improving the quality and efficiency of primary health care system is a key challenge. In this regard, problems that have accumulated in the system over the past decade - a weak material base of outpatient-polyclinic institutions, especially in rural areas; a surplus of medical personnel; lack of control by local, regional and central authorities--still remain as serious obstacle. The issue of financing the provided health services, is also particularly important, given the fact that a significant portion of the cost of medical services is covered by the patient directly. And as a consequence, the low level of applications for outpatient-polyclinic assistance due to declining affordability of medical services. In connection with the foregoing, the authors of the paper raise the question of implementing strict, multi-component system of quality control of medical care for patients. In particular, they propose: to base modern organization works on improving the quality of primary health care system on the principles of general management theory; Modern management of service quality should be clearly oriented towards the needs of the population in health care, its structure and dynamics; accessibility, incentives, determined by economic and technological competition characteristic to the market; Modern quality management, regardless of ownership and scale of outpatient-polyclinic establishment should optimally combine the actions, methods and tools that provide, on the one hand--the organization of diagnostic and therapeutic-prophylactic processes meeting the needs of the people, and on the other--the introduction of new methods and means to ensure the modern level of medical care; Schematic diagram of quality control mechanism organically interacts with the market research and includes a block of policy development in terms of quality.

  12. Simulation of the Australian Mobilesat signalling scheme

    NASA Technical Reports Server (NTRS)

    Rahman, Mushfiqur

    1990-01-01

    The proposed Australian Mobilesat system will provide a range of circuit switched voice/data services using the B-series satellites. The reliability of the signalling scheme between the Network Management Station (NMS) and the mobile terminal (MT) is of critical importance to the performance of the overall system. Simulation results of the performance of the signalling scheme under various channel conditions and coding schemes are presented.

  13. A meta-analysis to identify animal and management factors influencing gestating sow efficiency.

    PubMed

    Douglas, S L; Szyszka, O; Stoddart, K; Edwards, S A; Kyriazakis, I

    2014-12-01

    A meta-analysis on the effects of management and animal-based factors on the reproductive efficiency of gestating sows can provide information on single-factor and interaction effects that may not have been detected in individual studies. This study analyzed the effects of such factors on the number of piglets born alive per litter (BA), piglet birth weight (BiW) and weaning weight (WW), and number of piglets born alive per kilogram of sow feed intake during gestation (BA/FI). A total of 51 papers and 7 data sources were identified for the meta-analysis, out of which 23 papers and 5 sets of production data were useable (a total of 121 treatments). The information gathered included the dependent variables as well as information regarding animal, management, and feed characteristics. While a number of factors were individually significant, the multivariate models identified significant effects only of 1) floor type (P=0.003), sow BW at the end of gestation (P=0.002), and housing (stalls vs. loose; P=0.004) on BA; as floor type and housing were confounded, they were included in 2 separate models. The BA was higher on solid (12.1) in comparison to partly slatted (11.4) and fully slatted floors (10.2); 2) sow gestation environment (P=0.017) and gestation feed allowance (P=0.046) on BiW, with BiW of pigs higher for sows kept outdoors rather than indoors (1.75 versus 1.49 kg); 3) parity number (P=0.003) and feed intake during gestation (P=0.017) on WW; in addition there was an interaction between parity number×feed ME and parity number×feed CP content of feed during gestation on WW, with the positive effects of feed ME and CP contents seen during early rather than later parities; and 4) floor type (P=0.019) and feed crude fiber (P=0.003) for BA/FI with a greater number for those kept on solid floors (5.11) versus partially and fully slatted floors (4.07 and 4.05). The meta-analysis confirmed the significant effect of several well-known factors on the efficiency of

  14. Improvement of III-nitride visible and ultraviolet light-emitting diode performance, including extraction efficiency, electrical efficiency, thermal management and efficiency maintenance at high current densities

    NASA Astrophysics Data System (ADS)

    Vampola, Kenneth

    In this work, highly efficient broad-area LEDs on bulk GaN substrates were developed and the fabrication process and device layout were optimized. This optimization relied in part on electrical, optical, thermal and recombination models. The peak external quantum efficiency of the 450 nm LEDs was over 68% when biased at 20 mA. The efficiency characteristic showed a typical droop curve, decreasing at high current densities. The cause of this droop is unknown. An exploratory experiment was conducted to characterize electron overflow and its role in efficiency droop. Novel device structures were developed, allowing direct measurement of overflow electrons in LED-like structures under electrical injection. In these test structures, electrons were observed in the p-type region of the LED only at current densities where efficiency droop was active. The onset of efficiency droop was preceded by the onset of electron overflow. However, the magnitude of the overflow current could not be measured and it is undetermined whether the dominant cause of efficiency droop is electron overflow or some other process such as Auger recombination. Calibration structures allowing measurement of the magnitude of the overflow are proposed. Work on deep-ultraviolet, 275 nm, LEDs is also presented. Demonstration of direct-wafer bonded LEDs to beta-Ga2O3 is presented. A SiC substrate removal process is discussed. LEDs fabricated by this flip-chip process exhibited up to 1.8 times greater power compared to LEDs fabricated by a standard process but suffered from increased forward voltage and premature failure. Further process development leading to electrically efficient operation is proposed.

  15. A Measurement Management Technology for Improving Energy Efficiency in Data Centers and Telecommunication Facilities

    SciTech Connect

    Hendrik Hamann, Levente Klein

    2012-06-28

    Data center (DC) electricity use is increasing at an annual rate of over 20% and presents a concern for the Information Technology (IT) industry, governments, and the society. A large fraction of the energy use is consumed by the compressor cooling to maintain the recommended operating conditions for IT equipment. The most common way to improve the DC efficiency is achieved by optimally provisioning the cooling power to match the global heat dissipation in the DC. However, at a more granular level, the large range of heat densities of today's IT equipment makes the task of provisioning cooling power optimized to the level of individual computer room air conditioning (CRAC) units much more challenging. Distributed sensing within a DC enables the development of new strategies to improve energy efficiency, such as hot spot elimination through targeted cooling, matching power consumption at rack level with workload schedule, and minimizing power losses. The scope of Measurement and Management Technologies (MMT) is to develop a software tool and the underlying sensing technology to provide critical decision support and control for DC and telecommunication facilities (TF) operations. A key aspect of MMT technology is integration of modeling tools to understand how changes in one operational parameter affect the overall DC response. It is demonstrated that reduced ordered models for DC can generate, in less than 2 seconds computational time, a three dimensional thermal model in a 50 kft{sup 2} DC. This rapid modeling enables real time visualization of the DC conditions and enables 'what if' scenarios simulations to characterize response to 'disturbances'. One such example is thermal zone modeling that matches the cooling power to the heat generated at a local level by identifying DC zones cooled by a specific CRAC. Turning off a CRAC unit can be simulated to understand how the other CRAC utilization changes and how server temperature responds. Several new sensing

  16. Constructing an Efficient Self-Tuning Aircraft Engine Model for Control and Health Management Applications

    NASA Technical Reports Server (NTRS)

    Armstrong, Jeffrey B.; Simon, Donald L.

    2012-01-01

    Self-tuning aircraft engine models can be applied for control and health management applications. The self-tuning feature of these models minimizes the mismatch between any given engine and the underlying engineering model describing an engine family. This paper provides details of the construction of a self-tuning engine model centered on a piecewise linear Kalman filter design. Starting from a nonlinear transient aerothermal model, a piecewise linear representation is first extracted. The linearization procedure creates a database of trim vectors and state-space matrices that are subsequently scheduled for interpolation based on engine operating point. A series of steady-state Kalman gains can next be constructed from a reduced-order form of the piecewise linear model. Reduction of the piecewise linear model to an observable dimension with respect to available sensed engine measurements can be achieved using either a subset or an optimal linear combination of "health" parameters, which describe engine performance. The resulting piecewise linear Kalman filter is then implemented for faster-than-real-time processing of sensed engine measurements, generating outputs appropriate for trending engine performance, estimating both measured and unmeasured parameters for control purposes, and performing on-board gas-path fault diagnostics. Computational efficiency is achieved by designing multidimensional interpolation algorithms that exploit the shared scheduling of multiple trim vectors and system matrices. An example application illustrates the accuracy of a self-tuning piecewise linear Kalman filter model when applied to a nonlinear turbofan engine simulation. Additional discussions focus on the issue of transient response accuracy and the advantages of a piecewise linear Kalman filter in the context of validation and verification. The techniques described provide a framework for constructing efficient self-tuning aircraft engine models from complex nonlinear

  17. Management and development of land in the name of the Green Economy: planning, landscape, efficiency, biodiversity

    NASA Astrophysics Data System (ADS)

    Benvenuti, Paolo

    2016-04-01

    Promoting sustainable economic development is the basis of the Green Economy: a new vision of Agriculture, Environmental and Regional policy, shared by the wine sector, especially on some crucial issues, such as reducing the consumption of agricultural land, recognition as economically important of the green agricultural production space, spreading of organic farming, adoption of good agricultural practices. Sustainability, in fact , is not just about the use of analysis tools (carbonfoot print, Waterfoot print, etc .) but is about innovations to be introduced in the entire production process, protection of biodiversity, ethic work in the vineyard and winery. It means to disseminate as much as possible all those practices that can enable a more efficient land management also considering the recent climate changes: introduction of agro-energy and precision agriculture, rational use of water resources, creation of an observatory on temperatures and an interactive mapping system, viticultural zoning and municipal planning to make concrete balance between vitality in agronomic sector and landscape quality. Realizing such a regional geopedological mapping about agricultural soil, will allow companies to display a real-time access to all the data needed for a sustainable management of the funds, not only it would be an important tool to support the technical choices of farmers, enhancing their potential and optimizing production in relation to the current climate crisis, but would have a strong impact in terms of managing and saving water and energy resources. A strong efficacy in this context should be recognized at the "Urban Regulation Plans of the Wine Cities", which have developed since 2007 on the base of the guidelines promoted by the Italian Association Città del Vino, in order to enhance the quality of wine districts. The foundations of this multidisciplinary tool are based on: • in-depth knowledge of the characteristics of the wine territory; • unity and

  18. The economic and environmental consequences of implementing nitrogen-efficient technologies and management practices in agriculture.

    PubMed

    Zhang, Xin; Mauzerall, Denise L; Davidson, Eric A; Kanter, David R; Cai, Ruohong

    2015-03-01

    Technologies and management practices (TMPs) that reduce the application of nitrogen (N) fertilizer while maintaining crop yields can improve N use efficiency (NUE) and are important tools for meeting the dual challenges of increasing food production and reducing N pollution. However, because farmers operate to maximize their profits, incentives to implement TMPs are limited, and TMP implementation will not always reduce N pollution. Therefore, we have developed the NUE Economic and Environmental impact analytical framework (NUE) to examine the economic and environmental consequences of implementing TMPs in agriculture, with a specific focus on farmer profits, N fertilizer consumption, N losses, and cropland demand. Our analytical analyses show that impact of TMPs on farmers' economic decision-making and the environment is affected by how TMPs change the yield ceiling and the N fertilization rate at the ceiling and by how the prices of TMPs, fertilizer, and crops vary. Technologies and management practices that increase the yield ceiling appear to create a greater economic incentive for farmers than TMPs that do not but may result in higher N application rates and excess N losses. Nevertheless, the negative environmental impacts of certain TMPs could be avoided if their price stays within a range determined by TMP yield response, fertilizer price, and crop price. We use a case study on corn production in the midwestern United States to demonstrate how NUE can be applied to farmers' economic decision-making and policy analysis. Our NUE framework provides an important tool for policymakers to understand how combinations of fertilizer, crop, and TMP prices affect the possibility of achieving win-win outcomes for farmers and the environment. PMID:26023951

  19. Automatically high accurate and efficient photomask defects management solution for advanced lithography manufacture

    NASA Astrophysics Data System (ADS)

    Zhu, Jun; Chen, Lijun; Ma, Lantao; Li, Dejian; Jiang, Wei; Pan, Lihong; Shen, Huiting; Jia, Hongmin; Hsiang, Chingyun; Cheng, Guojie; Ling, Li; Chen, Shijie; Wang, Jun; Liao, Wenkui; Zhang, Gary

    2014-04-01

    Defect review is a time consuming job. Human error makes result inconsistent. The defects located on don't care area would not hurt the yield and no need to review them such as defects on dark area. However, critical area defects can impact yield dramatically and need more attention to review them such as defects on clear area. With decrease in integrated circuit dimensions, mask defects are always thousands detected during inspection even more. Traditional manual or simple classification approaches are unable to meet efficient and accuracy requirement. This paper focuses on automatic defect management and classification solution using image output of Lasertec inspection equipment and Anchor pattern centric image process technology. The number of mask defect found during an inspection is always in the range of thousands or even more. This system can handle large number defects with quick and accurate defect classification result. Our experiment includes Die to Die and Single Die modes. The classification accuracy can reach 87.4% and 93.3%. No critical or printable defects are missing in our test cases. The missing classification defects are 0.25% and 0.24% in Die to Die mode and Single Die mode. This kind of missing rate is encouraging and acceptable to apply on production line. The result can be output and reloaded back to inspection machine to have further review. This step helps users to validate some unsure defects with clear and magnification images when captured images can't provide enough information to make judgment. This system effectively reduces expensive inline defect review time. As a fully inline automated defect management solution, the system could be compatible with current inspection approach and integrated with optical simulation even scoring function and guide wafer level defect inspection.

  20. EUDAT and EPOS moving towards the efficient management of scientific data sets

    NASA Astrophysics Data System (ADS)

    Fiameni, Giuseppe; Bailo, Daniele; Cacciari, Claudio

    2016-04-01

    interoperability among all involved communities, EPOS has designed an architecture capable to organize and manage distributed discipline-oriented centers (called Thematic Core Services - TCS). Such design envisage the creation of an integrating e-Infrastructure called Integrated Core Service (ICS), whose aim is to collect and integrate Data, Data Products, Software and Services, and provide homogeneous access to them to the end user, hiding all the complexity of the underlying network of TCS and National data centers. Therefore, EPOS can take advantage of EUDAT CDI at different levels: at the TCS level, providing technologies, knowledge and B2* services to discipline-oriented communities, and at the ICS level, by facilitating the integration and interoperability of different communities with different level of maturity in terms of technology expertise. EUDAT services are particularly suitable to facilitate this process as they can be deployed across the community centers to complement or augment existing services of more mature communities as well as be used by less mature communities as a gateway towards the EPOS integration. To this purpose, a pilot is being carried on in the context of the EPOS Seismological community to foster the uptake of EUDAT services among centers and thus ensure the efficient and sustainable management of scientific data sets. Data sets, e.g. seismic waveforms, collected through the Italian Seismic Network and the ORFEUS organization, are currently replicated onto EUDAT resources to ensure their long-term preservation and accessibility. The pilot will be extend to cover other use cases such as the management of meta-data and the fine-grained control of access.

  1. Study on nitrogen load reduction efficiency of agricultural conservation management in a small agricultural watershed.

    PubMed

    Liu, Xiaoli; Chen, Qiuwen; Zeng, Zhaoxia

    2014-01-01

    Different crops can generate different non-point source (NPS) loads because of their spatial topography heterogeneity and variable fertilization application rates. The objective of this study was to assess nitrogen NPS load reduction efficiency by spatially adjusting crop plantings as an agricultural conservation management (ACM) measure in a typical small agricultural watershed in the black soil region in northeast China. The assessment was undertaken using the Soil and Water Assessment Tool (SWAT). Results showed that lowland crops produce higher nitrogen NPS loads than those in highlands. It was also found that corn gave a comparatively larger NPS load than soybeans due to its larger fertilization demand. The ACM assessed was the conversion of lowland corn crops into soybean crops and highland soybean crops into corn crops. The verified SWAT model was used to evaluate the impact of the ACM action on nitrogen loads. The results revealed that the ACM could reduce NO3-N and total nitrogen loads by 9.5 and 10.7%, respectively, without changing the area of crops. Spatially optimized regulation of crop planting according to fertilizer demand and geological landscapes can effectively decrease NPS nitrogen exports from agricultural watersheds. PMID:24759530

  2. Study on nitrogen load reduction efficiency of agricultural conservation management in a small agricultural watershed.

    PubMed

    Liu, Xiaoli; Chen, Qiuwen; Zeng, Zhaoxia

    2014-01-01

    Different crops can generate different non-point source (NPS) loads because of their spatial topography heterogeneity and variable fertilization application rates. The objective of this study was to assess nitrogen NPS load reduction efficiency by spatially adjusting crop plantings as an agricultural conservation management (ACM) measure in a typical small agricultural watershed in the black soil region in northeast China. The assessment was undertaken using the Soil and Water Assessment Tool (SWAT). Results showed that lowland crops produce higher nitrogen NPS loads than those in highlands. It was also found that corn gave a comparatively larger NPS load than soybeans due to its larger fertilization demand. The ACM assessed was the conversion of lowland corn crops into soybean crops and highland soybean crops into corn crops. The verified SWAT model was used to evaluate the impact of the ACM action on nitrogen loads. The results revealed that the ACM could reduce NO3-N and total nitrogen loads by 9.5 and 10.7%, respectively, without changing the area of crops. Spatially optimized regulation of crop planting according to fertilizer demand and geological landscapes can effectively decrease NPS nitrogen exports from agricultural watersheds.

  3. Fertilizer efficiency and environmental risk of irrigating Impatiens with composting leachate in decentralized solid waste management

    SciTech Connect

    Zhou Chuanbin; Wang Rusong; Zhang Yishan

    2010-06-15

    The reduction and reuse of composting leachate is an issue of importance in the field of decentralized solid waste management. In this study, composting leachate from source-separated food waste was treated and subsequently used as liquid fertilizer to irrigate Impatiens (Impatiens balsamina). The leachate was altered by adjusting storage time and dilution, and through addition of microbial inocula. For each test case, the effects of irrigation were monitored by analyzing the Impatiens extension degree, numbers of leaves and flowers, dry weight, and photosynthetic pigment content to assess fertilizer efficiency. The main results obtained revealed that the addition of microbial inocula and lengthening of storage times may lower COD concentrations, adjust pH value and maintain a comparatively high level of nutrient contents. By adding microbial inocula, a COD concentration of 9.6% and BOD{sub 5} concentration of 6.7% were obtained for non-treated leachate with the same storage time. COD concentrations in leachate decreased to 69.4% after 36 weeks storage. Moreover, composting leachate promoted growth of Impatiens. The dry weight biomass of Impatiens irrigated using treated diluted leachate was 1.15-2.94 times that obtained for Impatiens irrigated using tap water. Lastly, following the irrigation of Impatiens over a short period, soil did not accumulate VOCs and heavy metals to levels exceeding relative standards. Further research on heavy metal and salinity accumulation in plants should be undertaken to meet the needs of large-scale applications.

  4. Fertilizer efficiency and environmental risk of irrigating Impatiens with composting leachate in decentralized solid waste management.

    PubMed

    Zhou, Chuanbin; Wang, Rusong; Zhang, Yishan

    2010-06-01

    The reduction and reuse of composting leachate is an issue of importance in the field of decentralized solid waste management. In this study, composting leachate from source-separated food waste was treated and subsequently used as liquid fertilizer to irrigate Impatiens (Impatiens balsamina). The leachate was altered by adjusting storage time and dilution, and through addition of microbial inocula. For each test case, the effects of irrigation were monitored by analyzing the Impatiens extension degree, numbers of leaves and flowers, dry weight, and photosynthetic pigment content to assess fertilizer efficiency. The main results obtained revealed that the addition of microbial inocula and lengthening of storage times may lower COD concentrations, adjust pH value and maintain a comparatively high level of nutrient contents. By adding microbial inocula, a COD concentration of 9.6% and BOD(5) concentration of 6.7% were obtained for non-treated leachate with the same storage time. COD concentrations in leachate decreased to 69.4% after 36weeks storage. Moreover, composting leachate promoted growth of Impatiens. The dry weight biomass of Impatiens irrigated using treated diluted leachate was 1.15-2.94 times that obtained for Impatiens irrigated using tap water. Lastly, following the irrigation of Impatiens over a short period, soil did not accumulate VOCs and heavy metals to levels exceeding relative standards. Further research on heavy metal and salinity accumulation in plants should be undertaken to meet the needs of large-scale applications.

  5. Efficient use of information in adaptive management with an application to managing recreation near golden eagle nesting sites.

    PubMed

    Fackler, Paul L; Pacifici, Krishna; Martin, Julien; McIntyre, Carol

    2014-01-01

    It is generally the case that a significant degree of uncertainty exists concerning the behavior of ecological systems. Adaptive management has been developed to address such structural uncertainty, while recognizing that decisions must be made without full knowledge of how a system behaves. This paradigm attempts to use new information that develops during the course of management to learn how the system works. To date, however, adaptive management has used a very limited information set to characterize the learning that is possible. This paper uses an extension of the Partial Observable Markov Decision Process (POMDP) framework to expand the information set used to update belief in competing models. This feature can potentially increase the speed of learning through adaptive management, and lead to better management in the future. We apply this framework to a case study wherein interest lies in managing recreational restrictions around golden eagle (Aquila chrysaetos) nesting sites. The ultimate management objective is to maintain an abundant eagle population in Denali National Park while minimizing the regulatory burden on park visitors. In order to capture this objective, we developed a utility function that trades off expected breeding success with hiker access. Our work is relevant to the management of human activities in protected areas, but more generally demonstrates some of the benefits of POMDP in the context of adaptive management. PMID:25098955

  6. Efficient use of information in adaptive management with an application to managing recreation near golden eagle nesting sites.

    PubMed

    Fackler, Paul L; Pacifici, Krishna; Martin, Julien; McIntyre, Carol

    2014-01-01

    It is generally the case that a significant degree of uncertainty exists concerning the behavior of ecological systems. Adaptive management has been developed to address such structural uncertainty, while recognizing that decisions must be made without full knowledge of how a system behaves. This paradigm attempts to use new information that develops during the course of management to learn how the system works. To date, however, adaptive management has used a very limited information set to characterize the learning that is possible. This paper uses an extension of the Partial Observable Markov Decision Process (POMDP) framework to expand the information set used to update belief in competing models. This feature can potentially increase the speed of learning through adaptive management, and lead to better management in the future. We apply this framework to a case study wherein interest lies in managing recreational restrictions around golden eagle (Aquila chrysaetos) nesting sites. The ultimate management objective is to maintain an abundant eagle population in Denali National Park while minimizing the regulatory burden on park visitors. In order to capture this objective, we developed a utility function that trades off expected breeding success with hiker access. Our work is relevant to the management of human activities in protected areas, but more generally demonstrates some of the benefits of POMDP in the context of adaptive management.

  7. Efficient Use of Information in Adaptive Management with an Application to Managing Recreation near Golden Eagle Nesting Sites

    PubMed Central

    Fackler, Paul L.; Pacifici, Krishna; Martin, Julien; McIntyre, Carol

    2014-01-01

    It is generally the case that a significant degree of uncertainty exists concerning the behavior of ecological systems. Adaptive management has been developed to address such structural uncertainty, while recognizing that decisions must be made without full knowledge of how a system behaves. This paradigm attempts to use new information that develops during the course of management to learn how the system works. To date, however, adaptive management has used a very limited information set to characterize the learning that is possible. This paper uses an extension of the Partial Observable Markov Decision Process (POMDP) framework to expand the information set used to update belief in competing models. This feature can potentially increase the speed of learning through adaptive management, and lead to better management in the future. We apply this framework to a case study wherein interest lies in managing recreational restrictions around golden eagle (Aquila chrysaetos) nesting sites. The ultimate management objective is to maintain an abundant eagle population in Denali National Park while minimizing the regulatory burden on park visitors. In order to capture this objective, we developed a utility function that trades off expected breeding success with hiker access. Our work is relevant to the management of human activities in protected areas, but more generally demonstrates some of the benefits of POMDP in the context of adaptive management. PMID:25098955

  8. An energy-efficient MAC protocol using dynamic queue management for delay-tolerant mobile sensor networks.

    PubMed

    Li, Jie; Li, Qiyue; Qu, Yugui; Zhao, Baohua

    2011-01-01

    Conventional MAC protocols for wireless sensor network perform poorly when faced with a delay-tolerant mobile network environment. Characterized by a highly dynamic and sparse topology, poor network connectivity as well as data delay-tolerance, delay-tolerant mobile sensor networks exacerbate the severe power constraints and memory limitations of nodes. This paper proposes an energy-efficient MAC protocol using dynamic queue management (EQ-MAC) for power saving and data queue management. Via data transfers initiated by the target sink and the use of a dynamic queue management strategy based on priority, EQ-MAC effectively avoids untargeted transfers, increases the chance of successful data transmission, and makes useful data reach the target terminal in a timely manner. Experimental results show that EQ-MAC has high energy efficiency in comparison with a conventional MAC protocol. It also achieves a 46% decrease in packet drop probability, 79% increase in system throughput, and 25% decrease in mean packet delay.

  9. Demonstrating a Conceptual Framework to Provide Efficient Wound Management Service for a Wound Care Center in a Tertiary Hospital

    PubMed Central

    Chen, Yu-Tsung; Chang, Chang-Cheng; Shen, Jen-Hsiang; Lin, Wei-Nung; Chen, Mei-Yen

    2015-01-01

    Abstract Although the benefits of wound care services and multidisciplinary team care have been well elaborated on in the literature, there is a gap in the actual practice of wound care and the establishment of an efficient referral system. The conceptual framework for establishing efficient wound management services requires elucidation. A wound care center was established in a tertiary hospital in 2010, staffed by an integrated multidisciplinary team including plastic surgeons, a full-time coordinator, a physical therapist, occupational therapists, and other physician specialists. Referral patients were efficiently managed following a conceptual framework for wound care. This efficient wound management service consists of 3 steps: patient entry and onsite immediate wound debridement, wound re-evaluation, and individual wound bed preparation plan. Wound conditions were documented annually over 4 consecutive years. From January 2011 to December 2014, 1103 patients were recruited from outpatient clinics or inpatient consultations for the 3-step wound management service. Of these, 62% of patients achieved healing or improvement in wounds, 13% of patients experienced no change, and 25% of patients failed to follow-up. The outcome of wound treatment varied by wound type. Sixty-nine percent of diabetic foot ulcer patients were significantly healed or improved. In contrast, pressure ulcers were the most poorly healed wound type, with only 55% of patients achieving significantly healed or improved wounds. The 3-step wound management service in the wound care center efficiently provided onsite screening, timely debridement, and multidisciplinary team care. Patients could schedule appointments instead of waiting indefinitely for care. Further wound condition follow-up, education, and prevention were also continually provided. PMID:26554805

  10. Demonstrating a Conceptual Framework to Provide Efficient Wound Management Service for a Wound Care Center in a Tertiary Hospital.

    PubMed

    Chen, Yu-Tsung; Chang, Chang-Cheng; Shen, Jen-Hsiang; Lin, Wei-Nung; Chen, Mei-Yen

    2015-11-01

    Although the benefits of wound care services and multidisciplinary team care have been well elaborated on in the literature, there is a gap in the actual practice of wound care and the establishment of an efficient referral system. The conceptual framework for establishing efficient wound management services requires elucidation.A wound care center was established in a tertiary hospital in 2010, staffed by an integrated multidisciplinary team including plastic surgeons, a full-time coordinator, a physical therapist, occupational therapists, and other physician specialists. Referral patients were efficiently managed following a conceptual framework for wound care. This efficient wound management service consists of 3 steps: patient entry and onsite immediate wound debridement, wound re-evaluation, and individual wound bed preparation plan. Wound conditions were documented annually over 4 consecutive years.From January 2011 to December 2014, 1103 patients were recruited from outpatient clinics or inpatient consultations for the 3-step wound management service. Of these, 62% of patients achieved healing or improvement in wounds, 13% of patients experienced no change, and 25% of patients failed to follow-up. The outcome of wound treatment varied by wound type. Sixty-nine percent of diabetic foot ulcer patients were significantly healed or improved. In contrast, pressure ulcers were the most poorly healed wound type, with only 55% of patients achieving significantly healed or improved wounds.The 3-step wound management service in the wound care center efficiently provided onsite screening, timely debridement, and multidisciplinary team care. Patients could schedule appointments instead of waiting indefinitely for care. Further wound condition follow-up, education, and prevention were also continually provided.

  11. Eco-efficient approaches to land management: a case for increased integration of crop and animal production systems.

    PubMed

    Wilkins, R J

    2008-02-12

    Eco-efficiency is concerned with the efficient and sustainable use of resources in farm production and land management. It can be increased either by altering the management of individual crop and livestock enterprises or by altering the land-use system. This paper concentrates on the effects of crop sequence and rotation on soil fertility and nutrient use efficiency. The potential importance of mixed farming involving both crops and livestock is stressed, particularly when the systems incorporate biological nitrogen fixation and manure recycling. There is, however, little evidence that the trend in developed countries to farm-level specialization is being reduced. In some circumstances legislation to restrict diffuse pollution may provide incentives for more diverse eco-efficient farming and in other circumstances price premia for produce from eco-efficient systems, such as organic farming, and subsidies for the provision of environmental services may provide economic incentives for the adoption of such systems. However, change is likely to be most rapid where the present systems lead to obvious reductions in the productive potential of the land, such as in areas experiencing salinization. In other situations, there is promise that eco-efficiency could be increased on an area-wide basis by the establishment of linkages between farms of contrasting type, particularly between specialist crop and livestock farms, with contracts for the transfer of manures and, to a lesser extent, feeds. PMID:17652073

  12. Eco-efficient approaches to land management: a case for increased integration of crop and animal production systems.

    PubMed

    Wilkins, R J

    2008-02-12

    Eco-efficiency is concerned with the efficient and sustainable use of resources in farm production and land management. It can be increased either by altering the management of individual crop and livestock enterprises or by altering the land-use system. This paper concentrates on the effects of crop sequence and rotation on soil fertility and nutrient use efficiency. The potential importance of mixed farming involving both crops and livestock is stressed, particularly when the systems incorporate biological nitrogen fixation and manure recycling. There is, however, little evidence that the trend in developed countries to farm-level specialization is being reduced. In some circumstances legislation to restrict diffuse pollution may provide incentives for more diverse eco-efficient farming and in other circumstances price premia for produce from eco-efficient systems, such as organic farming, and subsidies for the provision of environmental services may provide economic incentives for the adoption of such systems. However, change is likely to be most rapid where the present systems lead to obvious reductions in the productive potential of the land, such as in areas experiencing salinization. In other situations, there is promise that eco-efficiency could be increased on an area-wide basis by the establishment of linkages between farms of contrasting type, particularly between specialist crop and livestock farms, with contracts for the transfer of manures and, to a lesser extent, feeds.

  13. Secure Dynamic access control scheme of PHR in cloud computing.

    PubMed

    Chen, Tzer-Shyong; Liu, Chia-Hui; Chen, Tzer-Long; Chen, Chin-Sheng; Bau, Jian-Guo; Lin, Tzu-Ching

    2012-12-01

    With the development of information technology and medical technology, medical information has been developed from traditional paper records into electronic medical records, which have now been widely applied. The new-style medical information exchange system "personal health records (PHR)" is gradually developed. PHR is a kind of health records maintained and recorded by individuals. An ideal personal health record could integrate personal medical information from different sources and provide complete and correct personal health and medical summary through the Internet or portable media under the requirements of security and privacy. A lot of personal health records are being utilized. The patient-centered PHR information exchange system allows the public autonomously maintain and manage personal health records. Such management is convenient for storing, accessing, and sharing personal medical records. With the emergence of Cloud computing, PHR service has been transferred to storing data into Cloud servers that the resources could be flexibly utilized and the operation cost can be reduced. Nevertheless, patients would face privacy problem when storing PHR data into Cloud. Besides, it requires a secure protection scheme to encrypt the medical records of each patient for storing PHR into Cloud server. In the encryption process, it would be a challenge to achieve accurately accessing to medical records and corresponding to flexibility and efficiency. A new PHR access control scheme under Cloud computing environments is proposed in this study. With Lagrange interpolation polynomial to establish a secure and effective PHR information access scheme, it allows to accurately access to PHR with security and is suitable for enormous multi-users. Moreover, this scheme also dynamically supports multi-users in Cloud computing environments with personal privacy and offers legal authorities to access to PHR. From security and effectiveness analyses, the proposed PHR access

  14. Efficient management and promotion of utilization of the video information acquired by observation

    NASA Astrophysics Data System (ADS)

    Kitayama, T.; Tanaka, K.; Shimabukuro, R.; Hase, H.; Ogido, M.; Nakamura, M.; Saito, H.; Hanafusa, Y.; Sonoda, A.

    2012-12-01

    In Japan Agency for Marine-Earth Science and Technology (JAMSTEC), the deep sea videos are made from the research by JAMSTEC submersibles in 1982, and the information on the huge deep-sea that will reach more 4,000 dives (ca. 24,700 tapes) by the present are opened to public via the Internet since 2002. The deep-sea videos is important because the time variation of deep-sea environment with difficult investigation and collection and growth of the living thing in extreme environment can be checked. Moreover, with development of video technique, the advanced analysis of an investigation image is attained. For grasp of deep sea environment, especially the utility value of the image is high. In JAMSTEC's Data Research Center for Marine-Earth Sciences (DrC), collection of the video are obtained by dive investigation of JAMSTEC, preservation, quality control, and open to public are performed. It is our big subject that the huge video information which utility value has expanded managed efficiently and promotion of use. In this announcement, the present measure is introduced about these subjects . The videos recorded on a tape or various media onboard are collected, and the backup and encoding for preventing the loss and degradation are performed. The video inside of a hard disk has the large file size. Then, we use the Linear Tape File System (LTFS) which attracts attention with image management engineering these days. Cost does not start compared with the usual disk backup, but correspondence years can also save the video data for a long time, and the operatively of a file is not different from a disk. The video that carried out the transcode to offer is archived by disk storage, and offer according to a use is possible for it. For the promotion of utilization of the video, the video public presentation system was reformed completely from November, 2011 to "JAMSTEC E-library of Deep Sea Images (http:// www.godac.jamstec.go.jp/jedi/)" This new system has preparing

  15. Regionalization of municipal solid waste management in Japan: balancing the proximity principle with economic efficiency.

    PubMed

    Okuda, Itaru; Thomson, Vivian E

    2007-07-01

    The proximity principle - disposing of waste close to its origin - has been a central value in municipal solid waste (MSW) management in Japan for the last 30 years and its widespread adoption has helped resolve numerous "Not in My Backyard" issues related to MSW management. However, MSW management costs have soared, in large part because of aggressive recycling efforts and because most MSW is incinerated in a country that has scarce landfill capacity. In addition, smaller, less sophisticated incinerators have been closed because of high dioxin emissions. Rising costs combined with the closure of smaller incinerators have shifted MSW management policy toward regionalization, which is the sharing of waste management facilities across municipalities. Despite the increased use of regionalized MSW facilities, the proximity principle remains the central value in Japanese MSW management. Municipal solid waste management has become increasingly regionalized in the United States, too, but different driving forces are at work in these two countries. The transition to regionalized MSW management in Japan results from strong governmental control at all levels, with the central government providing funds and policy direction and prefectures and municipalities being the primary implementing authorities. By contrast, market forces are a much stronger force with US MSW management, where local governments - with state government oversight - have primary responsibility for MSW management. We describe recent changes in Japan's MSW programs. We examine the connections between MSW facility regionalization, on the one hand, and, on the other hand, the proximity principle, coordination among local governments, central government control, and financing mechanisms. PMID:17530331

  16. How to Compute a Slot Marker - Calculation of Controller Managed Spacing Tools for Efficient Descents with Precision Scheduling

    NASA Technical Reports Server (NTRS)

    Prevot, Thomas

    2012-01-01

    This paper describes the underlying principles and algorithms for computing the primary controller managed spacing (CMS) tools developed at NASA for precisely spacing aircraft along efficient descent paths. The trajectory-based CMS tools include slot markers, delay indications and speed advisories. These tools are one of three core NASA technologies integrated in NASAs ATM technology demonstration-1 (ATD-1) that will operationally demonstrate the feasibility of fuel-efficient, high throughput arrival operations using Automatic Dependent Surveillance Broadcast (ADS-B) and ground-based and airborne NASA technologies for precision scheduling and spacing.

  17. Local flow management/profile descent algorithm. Fuel-efficient, time-controlled profiles for the NASA TSRV airplane

    NASA Technical Reports Server (NTRS)

    Groce, J. L.; Izumi, K. H.; Markham, C. H.; Schwab, R. W.; Thompson, J. L.

    1986-01-01

    The Local Flow Management/Profile Descent (LFM/PD) algorithm designed for the NASA Transport System Research Vehicle program is described. The algorithm provides fuel-efficient altitude and airspeed profiles consistent with ATC restrictions in a time-based metering environment over a fixed ground track. The model design constraints include accommodation of both published profile descent procedures and unpublished profile descents, incorporation of fuel efficiency as a flight profile criterion, operation within the performance capabilities of the Boeing 737-100 airplane with JT8D-7 engines, and conformity to standard air traffic navigation and control procedures. Holding and path stretching capabilities are included for long delay situations.

  18. Drip irrigation management in different chufa planting strategies: yield and irrigation water use efficiency

    NASA Astrophysics Data System (ADS)

    Pascual-Seva, Nuria; San Bautista, Alberto; López-Galarza, Salvador; Maroto, José Vicente; Pascual, Bernardo

    2013-04-01

    In a study presented in the EGU assembly 2012, it was analysed how yield and irrigation water use efficiency (IWUE) in chufa (Cyperus esculentus L. var. sativus), crop, were affected by planting strategy (ridges and flat raised beds, with two and three plant rows along them) and irrigation system [furrow (FI) and drip irrigation (DI)]. Each irrigation session started when the Volumetric Soil Water Content (VSWC) in ridges dropped to 80% of field capacity; beds were irrigated simultaneously with ridges and with the same irrigation duration. R produced lower yield than the two types of beds, and yields in DI were higher than those FI. Ridges led to the highest IWUE with DI, and to the lowest with FI. Then, it was decided to analyse, in DI, how yield and IWUE responded to start each irrigation session when the VSWC in the central point of different planting strategies [ridges (R), and flat raised beds with two (b) and three (B) plant rows along them] dropped to 80% of field capacity. In R and b, plants were irrigated by a single dripline per plant row, while in B two irrigation layouts were assayed: a single dripline per plant row (B3) and two driplines per bed (B2), placing each dripline between two planting rows. Irrigation session stop was also automated as a function of the VSWC. Results show that yield was affected (P˜0.01) by planting strategy; the greatest yield was obtained in b (2.4 kgm-2), differing (P˜0.05) from that obtained in R (2.1 kgm-2), with intermediate yields in B2 (2.3 kgm-2) and B3 (2.3 kgm-2). Yield was not affected (P˜0.05) by the utilisation of two or three driplines in B. Considerably less irrigation water was applied (IWA) in R (376 mm) than in B3 (465 mm), B2 (475 mm) and b (502 mm). This automatic irrigation management, as a function of the VSWC in each planting strategy, lead to adjust the IWA to the plant water requirements, which were similar in all three flat raised beds, since they correspond to the same planting density, that was

  19. New directions for hospital strategic management: the market for efficient care.

    PubMed

    Chilingerian, J A

    1992-01-01

    An analysis of current trends in the health care industry points to buyers seeking high quality, yet efficient, care as an emerging market segment. To target this market segment, hospitals must be prepared to market the efficient physicians. In the coming years, hospitals that can identify and market their best practicing providers will achieve a competitive advantage.

  20. Uncertainty Concerning the Efficiency and Effectiveness of Red Clay's Data Management and Processing Services

    ERIC Educational Resources Information Center

    Ammann, Charles

    2010-01-01

    For twenty-nine years, Red Clay Consolidated School District has managed data processing in a unique manner. Red Clay participates in the Data Service Center consortium to provide data management and processing services. This consortium is more independent than a department in the district but not as autonomous as an outsourced arrangement. While…

  1. Optimal Symmetric Ternary Quantum Encryption Schemes

    NASA Astrophysics Data System (ADS)

    Wang, Yu-qi; She, Kun; Huang, Ru-fen; Ouyang, Zhong

    2016-07-01

    In this paper, we present two definitions of the orthogonality and orthogonal rate of an encryption operator, and we provide a verification process for the former. Then, four improved ternary quantum encryption schemes are constructed. Compared with Scheme 1 (see Section 2.3), these four schemes demonstrate significant improvements in term of calculation and execution efficiency. Especially, under the premise of the orthogonal rate ɛ as secure parameter, Scheme 3 (see Section 4.1) shows the highest level of security among them. Through custom interpolation functions, the ternary secret key source, which is composed of the digits 0, 1 and 2, is constructed. Finally, we discuss the security of both the ternary encryption operator and the secret key source, and both of them show a high level of security and high performance in execution efficiency.

  2. 3DVEM Software Modules for Efficient Management of Point Clouds and Photorealistic 3d Models

    NASA Astrophysics Data System (ADS)

    Fabado, S.; Seguí, A. E.; Cabrelles, M.; Navarro, S.; García-De-San-Miguel, D.; Lerma, J. L.

    2013-07-01

    Cultural heritage managers in general and information users in particular are not usually used to deal with high-technological hardware and software. On the contrary, information providers of metric surveys are most of the times applying latest developments for real-life conservation and restoration projects. This paper addresses the software issue of handling and managing either 3D point clouds or (photorealistic) 3D models to bridge the gap between information users and information providers as regards the management of information which users and providers share as a tool for decision-making, analysis, visualization and management. There are not many viewers specifically designed to handle, manage and create easily animations of architectural and/or archaeological 3D objects, monuments and sites, among others. 3DVEM - 3D Viewer, Editor & Meter software will be introduced to the scientific community, as well as 3DVEM - Live and 3DVEM - Register. The advantages of managing projects with both sets of data, 3D point cloud and photorealistic 3D models, will be introduced. Different visualizations of true documentation projects in the fields of architecture, archaeology and industry will be presented. Emphasis will be driven to highlight the features of new userfriendly software to manage virtual projects. Furthermore, the easiness of creating controlled interactive animations (both walkthrough and fly-through) by the user either on-the-fly or as a traditional movie file will be demonstrated through 3DVEM - Live.

  3. A diagonally inverted LU implicit multigrid scheme

    NASA Technical Reports Server (NTRS)

    Yokota, Jeffrey W.; Caughey, David A.; Chima, Rodrick V.

    1988-01-01

    A new Diagonally Inverted LU Implicit scheme is developed within the framework of the multigrid method for the 3-D unsteady Euler equations. The matrix systems that are to be inverted in the LU scheme are treated by local diagonalizing transformations that decouple them into systems of scalar equations. Unlike the Diagonalized ADI method, the time accuracy of the LU scheme is not reduced since the diagonalization procedure does not destroy time conservation. Even more importantly, this diagonalization significantly reduces the computational effort required to solve the LU approximation and therefore transforms it into a more efficient method of numerically solving the 3-D Euler equations.

  4. Signature scheme based on bilinear pairs

    NASA Astrophysics Data System (ADS)

    Tong, Rui Y.; Geng, Yong J.

    2013-03-01

    An identity-based signature scheme is proposed by using bilinear pairs technology. The scheme uses user's identity information as public key such as email address, IP address, telephone number so that it erases the cost of forming and managing public key infrastructure and avoids the problem of user private generating center generating forgery signature by using CL-PKC framework to generate user's private key.

  5. Novel scheme for fast and efficent video sequence matching using compact signatures

    NASA Astrophysics Data System (ADS)

    Naphade, Milind R.; Yeung, Minerva M.; Yeo, Boon-Lock

    1999-12-01

    Efficient ways to manage digital video data have assumed enormous importance lately. An integral aspect is the ability to browse, index nd search huge volumes of video data automatically and efficiently. This paper presents a novel scheme for matching video sequences base on low-level features. The scheme supports fast and efficient matching and can search 450,000 frames of video data within 72 seconds on a 400 MHz. Pentium II, for a 50 frame query. Video sequences are processed in the compressed domain to extract the histograms of the images in the DCT sequence is implemented for matching video clips. The binds of the histograms of successive for comparison. This leads to efficient storage and transmission. The histogram representation can be compacted to 4.26 real numbers per frame, while achieving high matching accuracy. Multiple temporal resolution sampling of the videos to be matched is also supported and any key-frame-based matching scheme thus becomes a particular implementation of this scheme.

  6. Action versus result-oriented schemes in a grassland agroecosystem: a dynamic modelling approach.

    PubMed

    Sabatier, Rodolphe; Doyen, Luc; Tichit, Muriel

    2012-01-01

    Effects of agri-environment schemes (AES) on biodiversity remain controversial. While most AES are action-oriented, result-oriented and habitat-oriented schemes have recently been proposed as a solution to improve AES efficiency. The objective of this study was to compare action-oriented, habitat-oriented and result-oriented schemes in terms of ecological and productive performance as well as in terms of management flexibility. We developed a dynamic modelling approach based on the viable control framework to carry out a long term assessment of the three schemes in a grassland agroecosystem. The model explicitly links grazed grassland dynamics to bird population dynamics. It is applied to lapwing conservation in wet grasslands in France. We ran the model to assess the three AES scenarios. The model revealed the grazing strategies respecting ecological and productive constraints specific to each scheme. Grazing strategies were assessed by both their ecological and productive performance. The viable control approach made it possible to obtain the whole set of viable grazing strategies and therefore to quantify the management flexibility of the grassland agroecosystem. Our results showed that habitat and result-oriented scenarios led to much higher ecological performance than the action-oriented one. Differences in both ecological and productive performance between the habitat and result-oriented scenarios were limited. Flexibility of the grassland agroecosystem in the result-oriented scenario was much higher than in that of habitat-oriented scenario. Our model confirms the higher flexibility as well as the better ecological and productive performance of result-oriented schemes. A larger use of result-oriented schemes in conservation may also allow farmers to adapt their management to local conditions and to climatic variations.

  7. Valuing investments in sustainable land management using an integrated modelling framework to support a watershed conservation scheme in the Upper Tana River, Kenya

    NASA Astrophysics Data System (ADS)

    Hunink, Johannes E.; Bryant, Benjamin P.; Vogl, Adrian; Droogers, Peter

    2015-04-01

    We analyse the multiple impacts of investments in sustainable land use practices on ecosystem services in the Upper Tana basin (Kenya) to support a watershed conservation scheme (a "water fund"). We apply an integrated modelling framework, building on previous field-based and modelling studies in the basin, and link biophysical outputs to economic benefits for the main actors in the basin. The first step in the modelling workflow is the use of a high-resolution spatial prioritization tool (Resource Investment Optimization System -- RIOS) to allocate the type and location of conservation investments in the different subbasins, subject to budget constraints and stakeholder concerns. We then run the Soil and Water Assessment Tool (SWAT) using the RIOS-identified investment scenarios to produce spatially explicit scenarios that simulate changes in water yield and suspended sediment. Finally, in close collaboration with downstream water users (urban water supply and hydropower) we link those biophysical outputs to monetary metrics, including: reduced water treatment costs, increased hydropower production, and crop yield benefits for upstream farmers in the conservation area. We explore how different budgets and different spatial targeting scenarios influence the return of the investments and the effectiveness of the water fund scheme. This study is novel in that it presents an integrated analysis targeting interventions in a decision context that takes into account local environmental and socio-economic conditions, and then relies on detailed, process-based, biophysical models to demonstrate the economic return on those investments. We conclude that the approach allows for an analysis on different spatial and temporal scales, providing conclusive evidence to stakeholders and decision makers on the contribution and benefits of the land-based investments in this basin. This is serving as foundational work to support the implementation of the Upper Tana-Nairobi Water Fund

  8. Managing age-related hearing loss: how to use hearing aids efficiently - a mini-review.

    PubMed

    Williger, Bettina; Lang, Frieder R

    2014-01-01

    Using hearing aids may contribute to better functioning in the everyday lives of hearing-impaired older individuals. We introduce an integrative concept for the efficient use of hearing aids that involves both satisfaction with, and behaviour towards, hearing aids. We review theoretical and empirical work on the predictors of the efficient use of hearing aids in everyday life. Furthermore, we contend that the use of hearing aids requires improved understanding of the variability of hearing demands within specific contexts of everyday life (e.g. conversation with family members, listening to music). The efficiency of hearing aid use thus depends on the fit of situational demands, personal resources, and the specific configuration of the hearing aid device. We propose an integrative person-environment-fit model that advances concepts of selection, optimisation, and compensation to hearing aid efficiency. We discuss the implications of this model for research and for practitioners in the field of gerontology. PMID:24751499

  9. Practical intelligence at work: relationship between aging and cognitive efficiency among managers in a bank environment.

    PubMed

    Colonia-Willner, R

    1998-03-01

    A study was conducted to determine which better predicts performance among bank managers: tacit practical knowledge as assessed by the Tacit Knowledge Inventory for Managers (TKIM) or 2 psychometric measures of reasoning, the Raven's Advanced Progressive Matrices (Raven's) and the Verbal Reasoning subtest of the Differential Aptitude Test (DAT). Two hundred bank managers (43 experts and 157 nonexperts), ages 24-59 years old, participated. Increased age was associated with lower performance in Raven's and the DAT but less so in the TKIM; best performing older managers on average had high levels of tacit knowledge, although they scored lower on psychometric reasoning measures; TKIM predicted managerial skill; DAT and Raven's did not. These results suggest that stabilization of some aspects of intelligence may occur in old age. Implications of the findings for the study of practical intelligence, expertise, and compensatory abilities are discussed. PMID:9533189

  10. Simulation based energy-resource efficient manufacturing integrated with in-process virtual management

    NASA Astrophysics Data System (ADS)

    Katchasuwanmanee, Kanet; Cheng, Kai; Bateman, Richard

    2016-09-01

    As energy efficiency is one of the key essentials towards sustainability, the development of an energy-resource efficient manufacturing system is among the great challenges facing the current industry. Meanwhile, the availability of advanced technological innovation has created more complex manufacturing systems that involve a large variety of processes and machines serving different functions. To extend the limited knowledge on energy-efficient scheduling, the research presented in this paper attempts to model the production schedule at an operation process by considering the balance of energy consumption reduction in production, production work flow (productivity) and quality. An innovative systematic approach to manufacturing energy-resource efficiency is proposed with the virtual simulation as a predictive modelling enabler, which provides real-time manufacturing monitoring, virtual displays and decision-makings and consequentially an analytical and multidimensional correlation analysis on interdependent relationships among energy consumption, work flow and quality errors. The regression analysis results demonstrate positive relationships between the work flow and quality errors and the work flow and energy consumption. When production scheduling is controlled through optimization of work flow, quality errors and overall energy consumption, the energy-resource efficiency can be achieved in the production. Together, this proposed multidimensional modelling and analysis approach provides optimal conditions for the production scheduling at the manufacturing system by taking account of production quality, energy consumption and resource efficiency, which can lead to the key competitive advantages and sustainability of the system operations in the industry.

  11. Energy-efficient downlink resource management in self-organized OFDMA-based two-tier femtocell networks

    NASA Astrophysics Data System (ADS)

    Shahid, Adnan; Aslam, Saleem; Kim, Hyung Seok; Lee, Kyung-Geun

    2015-12-01

    Femtocell is a novel technology that is used for escalating indoor coverage as well as the capacity of traditional cellular networks. However, interference is the limiting factor for performance improvement due to co-channel deployment between macrocells and femtocells. The traditional network planning is not feasible because of the random deployment of femtocells. Therefore, self-organization approaches are the key to having successful deployment of femtocells. This study presents the joint resource block (RB) and power allocation task for the two-tier femtocell network in a self-organizing manner, with the concern to minimizing the impact of interference and maximizing the energy efficiency. In this study, we analyze the performance of the system in terms of the energy efficiency, which is composed of both the transmission and circuit power. Most of the previous studies investigate the performance regarding the throughput requirement of the two-tier femtocell network while the energy efficiency aspect is largely ignored. Here, the joint allocation task is modeled as a non-cooperative game which is demonstrated to exhibit pure and unique Nash equilibrium. In order to reduce the complexity of the proposed non-cooperative game, the joint RB and power allocation task is divided into two subproblems: an RB allocation and a particle swarm optimization-based power allocation. The analysis of the proposed game is carried out in terms of not only energy efficiency but also throughput. With practical 3rd Generation Partnership Project (3GPP) Long-Term Evolution (LTE) parameters, the simulation results illustrate the superior performance of the proposed game as compared to the traditional methods. Also, the comparison is carried out with the joint allocation scheme which only considers the throughput as the objective function. The results illustrate that significant performance improvement is achieved in terms of energy efficiency with slight loss in the throughput. The

  12. A secure data outsourcing scheme based on Asmuth-Bloom secret sharing

    NASA Astrophysics Data System (ADS)

    Idris Muhammad, Yusuf; Kaiiali, Mustafa; Habbal, Adib; Wazan, A. S.; Sani Ilyasu, Auwal

    2016-11-01

    Data outsourcing is an emerging paradigm for data management in which a database is provided as a service by third-party service providers. One of the major benefits of offering database as a service is to provide organisations, which are unable to purchase expensive hardware and software to host their databases, with efficient data storage accessible online at a cheap rate. Despite that, several issues of data confidentiality, integrity, availability and efficient indexing of users' queries at the server side have to be addressed in the data outsourcing paradigm. Service providers have to guarantee that their clients' data are secured against internal (insider) and external attacks. This paper briefly analyses the existing indexing schemes in data outsourcing and highlights their advantages and disadvantages. Then, this paper proposes a secure data outsourcing scheme based on Asmuth-Bloom secret sharing which tries to address the issues in data outsourcing such as data confidentiality, availability and order preservation for efficient indexing.

  13. The insurance and risk management industries: new players in thedelivery of energy-efficient and renewable energy products andservices

    SciTech Connect

    Mills, Evan

    2001-11-26

    The insurance industry is typically considered to have little concern about energy issues. However, the historical involvement by insurers and allied industries in the development and deployment of familiar loss-prevention technologies such as automobile air bags, fire prevention/suppression systems, and anti-theft devices, shows that this industry has a tradition of utilizing technology to improve safety and otherwise reduce the likelihood of losses for which they would otherwise have to pay. Through an examination of the connection between risk management and energy efficiency, we have identified nearly 80 examples of energy-efficient and renewable energy technologies that offer''loss-prevention'' benefits, and have mapped these opportunities onto the appropriate segments of the very diverse insurance sector (life, health,property, liability, business interruption, etc.). Some insurers and risk managers are beginning to recognize these previously un-noticed benefits.This paper presents the business case for insurer involvement in energy efficiency and documents case studies of insurer efforts along these lines. We review steps taken by 52 forward-looking insurers and reinsurers, 5 brokers, and 7 insurance organizations, and 13non-insurance organizations in the energy-efficiency arena. The approaches can be grouped into the categories of: information, education,and demonstration; financial incentives; specialized policies and products; direct investment to promote energy efficiency and renewables; value-added customer services and inspections; efficient codes,standards, and policies; research and development; and in-house energy management in insurer-owned properties. Specific examples include reduced premiums for architects and engineers who practice building commissioning(reduces risk of property loss and liability-related claims), insurer promotion of improved indoor air quality practices (mitigating life,health, and liability risks), and insurer promotion of

  14. Multiobjective hyper heuristic scheme for system design and optimization

    NASA Astrophysics Data System (ADS)

    Rafique, Amer Farhan

    2012-11-01

    As system design is becoming more and more multifaceted, integrated, and complex, the traditional single objective optimization trends of optimal design are becoming less and less efficient and effective. Single objective optimization methods present a unique optimal solution whereas multiobjective methods present pareto front. The foremost intent is to predict a reasonable distributed pareto-optimal solution set independent of the problem instance through multiobjective scheme. Other objective of application of intended approach is to improve the worthiness of outputs of the complex engineering system design process at the conceptual design phase. The process is automated in order to provide the system designer with the leverage of the possibility of studying and analyzing a large multiple of possible solutions in a short time. This article presents Multiobjective Hyper Heuristic Optimization Scheme based on low level meta-heuristics developed for the application in engineering system design. Herein, we present a stochastic function to manage meta-heuristics (low-level) to augment surety of global optimum solution. Generic Algorithm, Simulated Annealing and Swarm Intelligence are used as low-level meta-heuristics in this study. Performance of the proposed scheme is investigated through a comprehensive empirical analysis yielding acceptable results. One of the primary motives for performing multiobjective optimization is that the current engineering systems require simultaneous optimization of conflicting and multiple. Random decision making makes the implementation of this scheme attractive and easy. Injecting feasible solutions significantly alters the search direction and also adds diversity of population resulting in accomplishment of pre-defined goals set in the proposed scheme.

  15. The potential of value management (VM) to improve the consideration of energy efficiency within pre-construction

    NASA Astrophysics Data System (ADS)

    Tahir, Mohamad Zamhari; Nawi, Mohd Nasrun Mohd; Rajemi, Mohamad Farizal

    2016-08-01

    Energy demand and consumption in buildings will rise rapidly in the near future because of several social economics factors and this situation occurs not only in developed countries but also in developing countries such as Malaysia. There is demand towards building with energy efficiency features at this time, however most of the current buildings types are still being constructed with conventional designs, thus contribute to inefficient of energy consumption during the operation stage of the building. This paper presents the concept and the application of Value Management (VM) approach and its potential to improve consideration of energy efficiency within pre-construction process. Based on the relevant literatures, VM has provides an efficient and effective delivery system to fulfill the objectives and client's requirements. Generally in this paper, VM is discussed and scrutinized with reference to previous studies to see how these concepts contribute to better optimize the energy consumption in a building by seeking the best value energy efficiency through the design and construction process. This paper will not draw any conclusion but rather a preliminary research to propose the most energy efficiency measures to reliably accomplish a function that will meet the client's needs, desires and expectations. For further research in future, simple quantitative industry survey and VM workshops will be conducted to validate and further improve the research.

  16. Management of singlet and triplet excitons for efficient white organic light-emitting devices

    NASA Astrophysics Data System (ADS)

    Sun, Yiru; Giebink, Noel C.; Kanno, Hiroshi; Ma, Biwu; Thompson, Mark E.; Forrest, Stephen R.

    2006-04-01

    Lighting accounts for approximately 22 per cent of the electricity consumed in buildings in the United States, with 40 per cent of that amount consumed by inefficient (~15lmW-1) incandescent lamps. This has generated increased interest in the use of white electroluminescent organic light-emitting devices, owing to their potential for significantly improved efficiency over incandescent sources combined with low-cost, high-throughput manufacturability. The most impressive characteristics of such devices reported to date have been achieved in all-phosphor-doped devices, which have the potential for 100 per cent internal quantum efficiency: the phosphorescent molecules harness the triplet excitons that constitute three-quarters of the bound electron-hole pairs that form during charge injection, and which (unlike the remaining singlet excitons) would otherwise recombine non-radiatively. Here we introduce a different device concept that exploits a blue fluorescent molecule in exchange for a phosphorescent dopant, in combination with green and red phosphor dopants, to yield high power efficiency and stable colour balance, while maintaining the potential for unity internal quantum efficiency. Two distinct modes of energy transfer within this device serve to channel nearly all of the triplet energy to the phosphorescent dopants, retaining the singlet energy exclusively on the blue fluorescent dopant. Additionally, eliminating the exchange energy loss to the blue fluorophore allows for roughly 20 per cent increased power efficiency compared to a fully phosphorescent device. Our device challenges incandescent sources by exhibiting total external quantum and power efficiencies that peak at 18.7 +/- 0.5 per cent and 37.6 +/- 0.6lmW-1, respectively, decreasing to 18.4 +/- 0.5 per cent and 23.8 +/- 0.5lmW-1 at a high luminance of 500cdm-2.

  17. Bar Code-Based Management to Enhance Efficiency of a Sterile Supply Unit in Singapore.

    PubMed

    Goh, Meh Meh; Tan, Agnes B H; Leong, Mike H W

    2016-04-01

    Sterile surgical instruments are essential for successful surgical outcomes. The Singapore General Hospital's Theatre Sterile Supplies Unit (TSSU) has faced many challenges, including increasing demand for instruments and the need to maintain instruments of greater complexity. To address these challenges, stakeholders from key departments at Singapore General Hospital formed a multidisciplinary team to transform operations in the TSSU. The team adopted and implemented the TSSU Instrument Management System (TIMS) in three phases over five years. The project included standardizing instrument-naming conventions, implementing electronic integration of instrument tracking in the unit, extending traceability of instruments to the major ORs, initiating integrated web-based instrument ordering, and extending the system management of instruments at ambulatory surgery and specialized OR facilities. The implementation of TIMS has improved inventory, supply, and quality management; reduced instrument repairs; and led to savings through increased productivity and lower expenses.

  18. Bar Code-Based Management to Enhance Efficiency of a Sterile Supply Unit in Singapore.

    PubMed

    Goh, Meh Meh; Tan, Agnes B H; Leong, Mike H W

    2016-04-01

    Sterile surgical instruments are essential for successful surgical outcomes. The Singapore General Hospital's Theatre Sterile Supplies Unit (TSSU) has faced many challenges, including increasing demand for instruments and the need to maintain instruments of greater complexity. To address these challenges, stakeholders from key departments at Singapore General Hospital formed a multidisciplinary team to transform operations in the TSSU. The team adopted and implemented the TSSU Instrument Management System (TIMS) in three phases over five years. The project included standardizing instrument-naming conventions, implementing electronic integration of instrument tracking in the unit, extending traceability of instruments to the major ORs, initiating integrated web-based instrument ordering, and extending the system management of instruments at ambulatory surgery and specialized OR facilities. The implementation of TIMS has improved inventory, supply, and quality management; reduced instrument repairs; and led to savings through increased productivity and lower expenses. PMID:27004503

  19. Breeding programs for smallholder sheep farming systems: I. Evaluation of alternative designs of breeding schemes.

    PubMed

    Gizaw, S; Rischkowsky, B; Valle-Zárate, A; Haile, A; van Arendonk, J A M; Mwai, A O; Dessie, T

    2014-10-01

    Village- and central nucleus-based schemes were simulated and evaluated for their relative bio-economic efficiencies, using Ethiopia's Menz sheep as example. The schemes were: village-based 2-tier (Scheme-1) and 1-tier (Scheme-2) cooperative village breeding schemes, dispersed village-based nuclei scheme (Scheme-3), conventional 2-tier central nucleus-based scheme (Scheme-4), and schemes linking a central nucleus and village multiplier nuclei with selection in central nucleus (Scheme-5) or in both central and village nuclei (Scheme-6). Among village-based schemes, Scheme-1 gave the highest genetic progress, while Scheme-2 was economically the most efficient with genetic gain in the breeding objective of Birr 5.6 and a profit of Birr 37.2/ewe/year. The central nucleus schemes were more efficient than the village schemes. Scheme-4 was the most efficient with genetic gain in the breeding objective of Birr 13.5 and a profit of Birr 71.2, but is operationally more difficult as it requires a very large central nucleus. The choice between village and central nucleus-based schemes would depend on local conditions (availability of infrastructure, logistics and technical knowhow and support). Linking central nucleus with village-based nuclei (Scheme-6) would be a feasible option to overcome the operational difficulties of the conventional central nucleus scheme. If a village-based breeding program is envisaged as should be the 1st step in most low-input systems, then Scheme-2 is the most efficient. To scale out to an entire Menz breed level, Scheme-3 would be recommended.

  20. Nitrogen cycling: water use efficiency interactions in semi-arid ecosystems in relation to management of tree legumes (Prosopis)

    SciTech Connect

    Felker, P.; Clark, P.R.; Osborn, J.; Cannell, G.H.

    1980-04-01

    Plant productivity in semi-arid ecosystems is often limited by soil fertility as much as it is by moisture availability. A quantitative assessment of nitrogen limitations on water use efficiency has been made after careful review of plant water use efficiency data at high and low soil fertilities and after careful review of nitrogen inputs to semi arid ecosystems in the form of: blue-green algae-lichen crusts; non-symbiotic nitrogen fixers; rainfall; and tree legumes. This analysis indicates that plant productivity in semi-arid regions may be 10 fold more limited by nitrogen than moisture availability. Forage yields of non-nitrogen fixing trees and shrubs could be greatly increased by interplanting with drought adapted nitrogen fixers such as Prosopis and Acacia. Calculations based on water use efficiencies of annual legumes and nitrogen fixation values of tree legumes predict that well managed, spaced, and cared for orchards of specially selected Prosopis could produce 4000 Kgha/sup -1/ yr/sup -1/ of 13% protein pods at 500 mm annual rainfall with only light fertilization with phosphate, potassium and sulfur. Field measurements of pod yields for 25 selections of 3 year old Prosopis grown under managed orchard conditions in southern California are presented. Spacing regimes and harvesting techniques for Prosopis are proposed to facilitate pod production.

  1. NREL Works to Increase Electric Vehicle Efficiency Through Enhanced Thermal Management (Fact Sheet)

    SciTech Connect

    Not Available

    2014-06-01

    Researchers at NREL are providing new insight into how heating and cooling systems affect the distance that electric vehicles can travel on a single charge. Electric vehicle range can be reduced by as much as 68% per charge because of climate-control demands. NREL engineers are investigating opportunities to change this dynamic and increase driving range by improving vehicle thermal management. NREL experts are collaborating with automotive industry partners to investigate promising thermal management technologies and strategies, including zone-based cabin temperature controls, advanced heating and air conditioning controls, seat-based climate controls, vehicle thermal preconditioning, and thermal load reduction technologies.

  2. Nitrogen, stover and tillage management affect nitrogen use efficiency in continuous corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Improving nitrogen use efficiency (NUE) in corn (Zea mays L.) is critical for optimizing yield and reducing environmental impact. Stover removal in continuous corn (CC) for biofuel production, coupled with reduced-tillage systems, could alter NUE and residual soil nitrate-N. Experiments were conduct...

  3. A Practical and Cost Effective Demonstration of Efficient Energy Usage and Quality Management Using the NII

    SciTech Connect

    1999-05-01

    In order to be competitive in the changing electric power industry, and to promote energy efficiency and conservation, electric power providers need to have access to information on the power system to a level of detail that has not been available in the past. This level of detail extends beyond the usual voltage, current, power, and energy quantities obtained from traditional utility SCADA systems.

  4. The Impact of Information Technology Management on the Efficiency of Top Liberal Arts Colleges

    ERIC Educational Resources Information Center

    Eckles, James E.

    2011-01-01

    The purpose of this study is to provide administrators of liberal arts colleges with information that helps them improve their institutions' ability to graduate students. It investigates the relationship between IT and the efficiency of 35 highly ranked liberal arts colleges in graduating students. The study uses an operations research theory…

  5. Irrigation in water restricted regions: Managing water use efficiency with limited available water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Political and social pressures to increase water-use efficiency in agriculture from plant to regional scales are reaching critical levels. A region where these pressures have been extremely acute is most semi-arid parts of Texas where reliable crop production is possible only through irrigation. Re...

  6. Improving Safety, Quality and Efficiency through the Management of Emerging Processes: The TenarisDalmine Experience

    ERIC Educational Resources Information Center

    Bonometti, Patrizia

    2012-01-01

    Purpose: The aim of this contribution is to describe a new complexity-science-based approach for improving safety, quality and efficiency and the way it was implemented by TenarisDalmine. Design/methodology/approach: This methodology is called "a safety-building community". It consists of a safety-behaviour social self-construction process…

  7. ARQ scheme reinforced with past acknowledgement signals

    NASA Astrophysics Data System (ADS)

    Nakamura, Makoto; Takada, Yasushi

    An ARQ (automatic-repeat-request) scheme that can reduce the influence of backward channel errors for bidirectional data transmission systems is proposed. The main feature of the scheme is that both present and past acknowledgement signals are utilized to decide whether the data signals should be retransmitted or not. Throughput performance is analyzed in both go-back-N and selective-repeat ARQ. A small number of returned past acknowledgement signals are required to improve the throughput efficiency. For an ideal selective-repeat ARQ with an infinite buffer, increasing the number of returned past acknowledgement signals makes the throughput efficiency asymptotically close to the upper bound.

  8. Towards More Efficient Student Course Evaluations for Use at Management Level

    ERIC Educational Resources Information Center

    Rønsholdt, Bent; Brohus, Henrik

    2014-01-01

    In order to obtain an accreditation, the university management must implement a quality assurance system and be able to document that quality policy and procedures are followed and acted upon as appropriate. One element in this system is monitoring students' satisfaction. In this paper, we describe a method of acquiring the necessary…

  9. Summary of Characteristics and Energy Efficiency Demand-side Management Programs in the Southeastern United States

    SciTech Connect

    Glatt, Sandy

    2010-04-01

    This report is the first in a series that seeks to characterize energy supply and industrial sector energy consumption, and summarize successful industrial demand-side management (DSM) programs within each of the eight North American Electric Reliability Corporation (NERC) regions.

  10. Efficient Financial Management in Rural Schools: Common Problems and Solutions from the Field. ERIC Digest.

    ERIC Educational Resources Information Center

    Inman-Freitas, Deborah

    Based on a recent nationwide survey of rural administrators, this digest reports on the financial problems of rural school districts and some possible strategies for improvement. Rural administrators reported the following financial management problems: (1) cash flow problems due to late receipt of state aid or taxes; (2) expenditures that are…

  11. Collaboration for the Effective and Efficient Management of School Financial Resources

    ERIC Educational Resources Information Center

    Mestry, Raj; Govindasamy, Vanitha

    2013-01-01

    This paper examines the collaborative relationship between principals and School Governing Bodies (SGBs), and how this impacts on the management of financial resources in public schools. In South Africa, educational trends such as decentralisation, the shift of responsibility in roles, community involvement, building of partnerships and…

  12. The NEC Link Scheme

    ERIC Educational Resources Information Center

    Noakes, Peter

    1976-01-01

    Describes the operation of the National Electronics Council (NEC) Link Scheme for schools in Great Britain. The service is intended to provide technical assistance, information concerning surplus equipment, and guest speakers for school aspiring professional electronic counsel. (CP)

  13. [Efficient OP management. Suggestions for optimisation of organisation and administration as a basis for establishing statutes for operating theatres].

    PubMed

    Geldner, G; Eberhart, L H J; Trunk, S; Dahmen, K G; Reissmann, T; Weiler, T; Bach, A

    2002-09-01

    Economic aspects have gained increasing importance in recent years. The operating room (OR) is the most cost-intensive sector and determines the turnover process of a surgical patient within the hospital. Thus, optimisation of workflow processes is of particular interest for health care providers. If the results of surgery are viewed as a product, everything associated with surgery can be evaluated analogously to a manufacturing process. All steps involved in producing the end-result can and should be analysed with the goal of producing an efficient, economical and quality product. The leadership that physicians can provide to manage this process is important and leads to the introduction of a specialised "OR manager". This position must have the authority to issue directives to all other members of the OR team. An OR management subordinates directly to the administration of the hospital. By integrating and improving management of various elements of the surgical process, health care institutions are able to rationally trim costs while maintaining high-quality services. This paper gives a short introduction into the difficulties of organising an OR. Some suggestions are made to overcome common shortcomings in the daily practise. A proposal for an "OR statute" is presented that should be a basis for discussion within the OR team. It must be modified according to individual needs and prerequisites in every hospital. The single best opportunity for dramatic improvement in effective resource use in surgical services lies in the perioperative process. The management strategy must focus on process measurement using information technology and feed-back implementing modern quality management tools.However, no short-term effects can be expected from these changes. Improvements take about a year and continuous feed-back of all measures must accompany the reorganisation process.

  14. Eco-efficiency for greenhouse gas emissions mitigation of municipal solid waste management: a case study of Tianjin, China.

    PubMed

    Zhao, Wei; Huppes, Gjalt; van der Voet, Ester

    2011-06-01

    The issue of municipal solid waste (MSW) management has been highlighted in China due to the continually increasing MSW volumes being generated and the limited capacity of waste treatment facilities. This article presents a quantitative eco-efficiency (E/E) analysis on MSW management in terms of greenhouse gas (GHG) mitigation. A methodology for E/E analysis has been proposed, with an emphasis on the consistent integration of life cycle assessment (LCA) and life cycle costing (LCC). The environmental and economic impacts derived from LCA and LCC have been normalized and defined as a quantitative E/E indicator. The proposed method was applied in a case study of Tianjin, China. The study assessed the current MSW management system, as well as a set of alternative scenarios, to investigate trade-offs between economy and GHG emissions mitigation. Additionally, contribution analysis was conducted on both LCA and LCC to identify key issues driving environmental and economic impacts. The results show that the current Tianjin's MSW management system emits the highest GHG and costs the least, whereas the situation reverses in the integrated scenario. The key issues identified by the contribution analysis show no linear relationship between the global warming impact and the cost impact in MSW management system. The landfill gas utilization scenario is indicated as a potential optimum scenario by the proposed E/E analysis, given the characteristics of MSW, technology levels, and chosen methodologies. The E/E analysis provides an attractive direction towards sustainable waste management, though some questions with respect to uncertainty need to be discussed further. PMID:21316937

  15. Eco-efficiency for greenhouse gas emissions mitigation of municipal solid waste management: a case study of Tianjin, China.

    PubMed

    Zhao, Wei; Huppes, Gjalt; van der Voet, Ester

    2011-06-01

    The issue of municipal solid waste (MSW) management has been highlighted in China due to the continually increasing MSW volumes being generated and the limited capacity of waste treatment facilities. This article presents a quantitative eco-efficiency (E/E) analysis on MSW management in terms of greenhouse gas (GHG) mitigation. A methodology for E/E analysis has been proposed, with an emphasis on the consistent integration of life cycle assessment (LCA) and life cycle costing (LCC). The environmental and economic impacts derived from LCA and LCC have been normalized and defined as a quantitative E/E indicator. The proposed method was applied in a case study of Tianjin, China. The study assessed the current MSW management system, as well as a set of alternative scenarios, to investigate trade-offs between economy and GHG emissions mitigation. Additionally, contribution analysis was conducted on both LCA and LCC to identify key issues driving environmental and economic impacts. The results show that the current Tianjin's MSW management system emits the highest GHG and costs the least, whereas the situation reverses in the integrated scenario. The key issues identified by the contribution analysis show no linear relationship between the global warming impact and the cost impact in MSW management system. The landfill gas utilization scenario is indicated as a potential optimum scenario by the proposed E/E analysis, given the characteristics of MSW, technology levels, and chosen methodologies. The E/E analysis provides an attractive direction towards sustainable waste management, though some questions with respect to uncertainty need to be discussed further.

  16. Energy Efficiency Improvement and Cost Saving Opportunities for the Pharmaceutical Industry. An ENERGY STAR Guide for Energy and Plant Managers

    SciTech Connect

    Galitsky, Christina; Galitsky, Christina; Chang, Sheng-chieh; Worrell, Ernst; Masanet, Eric

    2008-03-01

    The U.S. pharmaceutical industry consumes almost $1 billion in energy annually. Energy efficiency improvement is an important way to reduce these costs and to increase predictable earnings, especially in times of high energy price volatility. There are a variety of opportunities available at individual plants in the U.S. pharmaceutical industry to reduce energy consumption in a cost-effective manner. This Energy Guide discusses energy efficiency practices and energy efficient technologies that can be implemented at the component, process, system, and organizational levels. A discussion of the trends, structure, and energy consumption characteristics of the U.S. pharmaceutical industry is provided along with a description of the major process steps in the pharmaceutical manufacturing process. Expected savings in energy and energy-related costs are given for many energy efficiency measures, based on case study data from real-world applications in pharmaceutical and related facilities worldwide. Typical measure payback periods and references to further information in the technical literature are also provided, when available. The information in this Energy Guide is intended to help energy and plant managers reduce energy consumption in a cost-effective manner while meeting regulatory requirements and maintaining the quality of products manufactured. At individual plants, further research on the economics of the measures?as well as their applicability to different production practices?is needed to assess potential implementation of selected technologies.

  17. Graph Databases for Large-Scale Healthcare Systems: A Framework for Efficient Data Management and Data Services

    SciTech Connect

    Park, Yubin; Shankar, Mallikarjun; Park, Byung H.; Ghosh, Dr. Joydeep

    2014-01-01

    Designing a database system for both efficient data management and data services has been one of the enduring challenges in the healthcare domain. In many healthcare systems, data services and data management are often viewed as two orthogonal tasks; data services refer to retrieval and analytic queries such as search, joins, statistical data extraction, and simple data mining algorithms, while data management refers to building error-tolerant and non-redundant database systems. The gap between service and management has resulted in rigid database systems and schemas that do not support effective analytics. We compose a rich graph structure from an abstracted healthcare RDBMS to illustrate how we can fill this gap in practice. We show how a healthcare graph can be automatically constructed from a normalized relational database using the proposed 3NF Equivalent Graph (3EG) transformation.We discuss a set of real world graph queries such as finding self-referrals, shared providers, and collaborative filtering, and evaluate their performance over a relational database and its 3EG-transformed graph. Experimental results show that the graph representation serves as multiple de-normalized tables, thus reducing complexity in a database and enhancing data accessibility of users. Based on this finding, we propose an ensemble framework of databases for healthcare applications.

  18. Energy Management in Small Commercial Buildings: A Look at How HVAC Contractors Can Deliver Energy Efficiency to this Segment

    SciTech Connect

    Hult, Erin; Granderson, Jessica; Mathew, Paul

    2014-07-01

    While buildings smaller than 50,000 sq ft account for nearly half of the energy used in US commercial buildings, energy efficiency programs to-date have primarily focused on larger buildings. Interviews with stakeholders and a review of the literature indicate interest in energy efficiency from the small commercial building sector, provided solutions are simple and low-cost. An approach to deliver energy management to small commercial buildings via HVAC contractors and preliminary demonstration findings are presented. The energy management package (EMP) developed includes five technical elements: benchmarking and analysis of monthly energy use; analysis of interval electricity data (if available), a one-hour onsite walkthrough, communication with the building owner, and checking of results. This data-driven approach tracks performance and identifies low-cost opportunities, using guidelines and worksheets for each element to streamline the delivery process and minimize the formal training required. This energy management approach is unique from, but often complementary to conventional quality maintenance or retrofit-focused programs targeting the small commercial segment. Because HVAC contractors already serve these clients, the transaction cost to market and deliver energy management services can be reduced to the order of hundreds of dollars per year. This business model, outlined briefly in this report, enables the offering to benefit the contractor and client even at the modest expected energy savings in small buildings. Results from a small-scale pilot of this approach validated that the EMP could be delivered by contractors in 4-8 hours per building per year, and that energy savings of 3-5percent are feasible through this approach.

  19. A Real Quantum Designated Verifier Signature Scheme

    NASA Astrophysics Data System (ADS)

    Shi, Wei-Min; Zhou, Yi-Hua; Yang, Yu-Guang

    2015-09-01

    The effectiveness of most quantum signature schemes reported in the literature can be verified by a designated person, however, those quantum signature schemes aren't the real traditional designated verifier signature schemes, because the designated person hasn't the capability to efficiently simulate a signature which is indistinguishable from a signer, which cannot satisfy the requirements in some special environments such as E-voting, call for tenders and software licensing. For solving this problem, a real quantum designated verifier signature scheme is proposed in this paper. According to the property of unitary transformation and quantum one-way function, only a verifier designated by a signer can verify the "validity of a signature" and the designated verifier cannot prove to a third party that the signature was produced by the signer or by himself through a transcript simulation algorithm. Moreover, the quantum key distribution and quantum encryption algorithm guarantee the unconditional security of this scheme. Analysis results show that this new scheme satisfies the main security requirements of designated verifier signature scheme and the major attack strategies.

  20. Steady-State Analysis Model for Advanced Fuel Cycle Schemes.

    2008-03-17

    Version 00 SMAFS was developed as a part of the study, "Advanced Fuel Cycles and Waste Management", which was performed during 2003-2005 by an ad-hoc expert group under the Nuclear Development Committee in the OECD/NEA. The model was designed for an efficient conduct of nuclear fuel cycle scheme cost analyses. It is simple, transparent and offers users the capability to track down cost analysis results. All the fuel cycle schemes considered in the model aremore » represented in a graphic format and all values related to a fuel cycle step are shown in the graphic interface, i.e., there are no hidden values embedded in the calculations. All data on the fuel cycle schemes considered in the study including mass flows, waste generation, cost data, and other data such as activities, decay heat and neutron sources of spent fuel and high-level waste along time are included in the model and can be displayed. The user can easily modify values of mass flows and/or cost parameters and see corresponding changes in the results. The model calculates: front-end fuel cycle mass flows such as requirements of enrichment and conversion services and natural uranium; mass of waste based on the waste generation parameters and the mass flow; and all costs.« less

  1. Steady-state Analysis Model for Advanced Fuelcycle Schemes

    2006-05-12

    The model was developed as a part of the study, "Advanced Fuel Cycles and Waste Management", which was performed during 2003—2005 by an ad-hoc expert group under the Nuclear Development Committee in the OECD/NEA. The model was designed for an efficient conduct of nuclear fuel cycle scheme cost analyses. It is simple, transparent and offers users the capability to track down the cost analysis results. All the fuel cycle schemes considered in the model aremore » represented in a graphic format and all values related to a fuel cycle step are shown in the graphic interface, i.e., there are no hidden values embedded in the calculations. All data on the fuel cycle schemes considered in the study including mass flows, waste generation, cost data, and other data such as activities, decay heat and neutron sources of spent fuel and high—level waste along time are included in the model and can be displayed. The user can modify easily the values of mass flows and/or cost parameters and see the corresponding changes in the results. The model calculates: front—end fuel cycle mass flows such as requirements of enrichment and conversion services and natural uranium; mass of waste based on the waste generation parameters and the mass flow; and all costs. It performs Monte Carlo simulations with changing the values of all unit costs within their respective ranges (from lower to upper bounds).« less

  2. ONU Power Saving Scheme for EPON System

    NASA Astrophysics Data System (ADS)

    Mukai, Hiroaki; Tano, Fumihiko; Tanaka, Masaki; Kozaki, Seiji; Yamanaka, Hideaki

    PON (Passive Optical Network) achieves FTTH (Fiber To The Home) economically, by sharing an optical fiber among plural subscribers. Recently, global climate change has been recognized as a serious near term problem. Power saving techniques for electronic devices are important. In PON system, the ONU (Optical Network Unit) power saving scheme has been studied and defined in XG-PON. In this paper, we propose an ONU power saving scheme for EPON. Then, we present an analysis of the power reduction effect and the data transmission delay caused by the ONU power saving scheme. According to the analysis, we propose an efficient provisioning method for the ONU power saving scheme which is applicable to both of XG-PON and EPON.

  3. Wound management for the 21st century: combining effectiveness and efficiency.

    PubMed

    Lindholm, Christina; Searle, Richard

    2016-07-01

    Treatment of wounds of different aetiologies constitutes a major part of the total health care budget. It is estimated that 1·5-2 million people in Europe suffer from acute or chronic wounds. These wounds are managed both in hospitals and in community care. The patients suffering from these wounds report physical, mental and social consequences of their wounds and the care of them. It is often believed that the use of wound dressings per se is the major cost driver in wound management, whereas in fact, nursing time and hospital costs are together responsible for around 80-85% of the total cost. Healing time, frequency of dressing change and complications are three important cost drivers. However, with the use of modern, advanced technology for more rapid wound healing, all these cost drivers can be substantially reduced. A basic understanding of the terminology and principles of Health Economics in relation to wound management might therefore be of interest. PMID:27460943

  4. Efficacy and efficiency of Agri-environmental payments in impacts of crops' management

    NASA Astrophysics Data System (ADS)

    Blasi, Emanuele; Martella, Angelo; Passeri, Nicolo; Ghini, Paolo

    2015-04-01

    Since the 90s, in Europe the Common Agricultural Policy (CAP) started to activate measures for improving the sustainability of European agriculture, these measures were systematized in 2000 with the tools of rural development, pursuing a synergistic environmental action trough the agri-environmental payments. Since their definition, those payments were designed to ensure the protection, maintenance and enhancement of natural resources (water, soil, forests), biodiversity (species and habitat), and landscape. In particular initiatives as set aside, afforestation, organic agriculture, integrated pest management, low input and precision agriculture have enriched the agricultural management practices. The aim of this work is to check the trend between agro-environmental subsidies and environmental performance (based on Ecological Indicators and CO2 evaluation) at country level in EU, in order to study the regulatory framework impact in addressing the European cropping system towards sustainability. In particular soils and their land use can storage CO2 as pool and so provide environmental services and, on the other hand the agricultural practices can stimulate the emission and the environmental footprint. Impacts (so called emissions/footprints and storage/environmental services) will be compared with the Agri-environmental Payments for calculating performances due to environmental management practices, supported by political initiatives. Such analysis sustains the European policy makers towards more suitable agricultural policies and in particular it can address national sustainability through agricultural practices.

  5. Drinking Water Quality Criterion - Based site Selection of Aquifer Storage and Recovery Scheme in Chou-Shui River Alluvial Fan

    NASA Astrophysics Data System (ADS)

    Huang, H. E.; Liang, C. P.; Jang, C. S.; Chen, J. S.

    2015-12-01

    Land subsidence due to groundwater exploitation is an urgent environmental problem in Choushui river alluvial fan in Taiwan. Aquifer storage and recovery (ASR), where excess surface water is injected into subsurface aquifers for later recovery, is one promising strategy for managing surplus water and may overcome water shortages. The performance of an ASR scheme is generally evaluated in terms of recovery efficiency, which is defined as percentage of water injected in to a system in an ASR site that fulfills the targeted water quality criterion. Site selection of an ASR scheme typically faces great challenges, due to the spatial variability of groundwater quality and hydrogeological condition. This study proposes a novel method for the ASR site selection based on drinking quality criterion. Simplified groundwater flow and contaminant transport model spatial distributions of the recovery efficiency with the help of the groundwater quality, hydrological condition, ASR operation. The results of this study may provide government administrator for establishing reliable ASR scheme.

  6. Design of a Pretreatment and Enzymatic Saccharification Scheme of Understory from Managed Pine Forest for a Biochemical-Refinery Platform: The Example of the Sweetgum Tree

    NASA Astrophysics Data System (ADS)

    Djioleu, Angele Mezindjou

    The possibility of using sweetgum from southern pine dominated forests as a biobased refinery feedstock was investigated. First, a baseline hydrolysis scheme for sweetgum wood and bark was designed. Sweetgum wood and bark were pretreated with 0.98% (v/v) sulfuric acid at 140°C for 30, 40, 50, 60 or 70 min and at 160°C for 30, 40, 50 or 60 min. The water insoluble solid (WIS) fraction was hydrolyzed with a cellulase enzyme cocktail. Results showed that maximum xylose and glucose yields from the wood were 82 and 86%, respectively. Similarly, the respective maximum yields of xylose and glucose from the bark were 93 and 24%. Concentrations of detected inhibitory compounds such as furfural, hydroxymethylfurfural (HMF), formic acid and acetic acid ranged from 0.1 to 32.3 g/ 100 g of raw dry biomass. The second part of this project investigated the effect of adding oak wood, sweetgum bark, or oak bark, to sweetgum wood on xylose and glucose yields obtained from dilute acid pretreatment and enzymatic hydrolysis. Carbohydrate recoveries for each species and mixed biomass samples were obtained by using previously established hydrolysis protocols at 160°C for 20 min. Mixed biomass samples were prepared to reflect real-life forestry harvesting scenario and consisted of 70% sweetgum wood plus 1) 30% sweetgum bark; 2) 30% oak bark; 3) 30% oak wood. 100% sweetgum was the control. Results showed that oak wood yielded 35% of its theoretical xylose content and sweetgum wood, 65%. Both woody species resulted in higher glucose and lower formic acid recoveries than their respective bark material. Analysis of data with the Dunnett Control's test in JMP 10.0 showed contamination of sweetgum wood did not have a significant effect (P > 0.05) on hydrolysis except with sweetgum bark which exhibited a significantly higher xylose concentration than the control. In conclusion, sweetgum wood was a good source of carbohydrate for a biobased refinery, but the removal of bark might be necessary

  7. Unintended consequence of managing the coupled humans and water: the irrigation efficiency paradox

    NASA Astrophysics Data System (ADS)

    Liu, Y.

    2015-12-01

    Water shortage most severely restricts the socio-economic development of many arid and semi-arid regions in the world, for which water-saving technology is believed to be an effective solution. However, as a realworld case, the total water consumption of Xinjiang Uygur Autonomous Region of China continued to increase as irrigation efficiency dramatically improved through the application of water-saving technology in the study period 1998-2010. This phenomenon, known as the irrigation efficiency paradox or Jevons paradox, is interpreted as an economic rebound effect. In this study, we explore the dynamic feedbacks between humans and water in this paradox through a socio-hydrological perspective. We analyze the co-evolutionary trajectory of coupled human-water dynamics from 1950 to 2010 to provide it a general context. A conceptual socio-hydrological model based on five key elements, namely, irrigation land, water-saving technology, water consumption, societal sensitivity to water scarcity, and the policy mix, is constructed. The policy mix to be adopted is determined by a social decision-making process mainly based on the societal sensitivity, which reflects the societal preference on two sorts of policies: (i) irrigation land control and (ii) water-saving technology promotion. Modeling results verify the hypothesized mechanism by successfully reproducing the observed dynamics including the emergence of the efficiency paradox. Our analysis indicates that the implementation of more adaptive rules may even eliminate the paradox. The effects of different initial policy mixes are also explored, and the results show that land control policies should be given equal priority when dealing with water scarcity. These findings point to a double-helix-type co-evolution of humans and water.

  8. Efficient On-demand Connection Management Mechanisms with PGAS Models on InfiniBand

    SciTech Connect

    Vishnu, Abhinav; Krishnan, Manoj Kumar

    2010-05-17

    In the last decade or so, clusters have observed a tremendous rise in popularity due to the excellent price to performance ratio. A variety of Interconnects have been proposed during this period, with InfiniBand leading the way due to its high performance and open standard. At the same time, multiple programming models have emerged in order to meet the requirements of various applications and their programming models. To support requirements of multiple programming models, InfiniBand provides multiple transport semantics, ranging from unreliable connectionless to reliable connected characteristics. Among them, the reliable connection (RC) semantics is being widely due to its high performance and support for novel features like Remote Direct Memory Acesss (RDMA), hardware atomics and Network Fault Tolerance. However, the pairwise connection oriented nature of the RC transport semantics limits its scalability and usage at the increasing processor counts. In this paper, we design and implement on-demand connection management approaches in the context of Partitioned Global Address Space (PGAS) programming models, which provided shared memory abstraction and one-sided communication semantics, leading to the development of multiple languages (UPC, X10, Chapel) and libraries (Global Arrays, MPI-RMA). Using Global Arrays as the research vehicle, we implement this approach with Aggregate Remote Memory Copy Interface (ARMCI), the runtime system of Global Arrays. We evaluate our approach, ARMCI-On Demand Connection Management (ARMCI-ODCM) using various microbenchmarks and benchmarks (LU Factorization, RandomAccess and Lennard Jones simulation) and application (Subsurface transport over multiple phases (STOMP)). With the performance evaluation for up to 4096 processors, we are able to have a multi-fold reduction in connection memory with a negligible degradation in performance. Using STOMP at 4096 processors, reduces the overall connection memory by 66 times with no

  9. An efficient strategy of managing irrigation water based on formulating highly absorbent polymer-inorganic clay composites

    NASA Astrophysics Data System (ADS)

    Berber, Mohamed R.; Hafez, Inas H.; Minagawa, Keiji; Tanaka, Masami; Mori, Takeshi

    2012-11-01

    SummaryThe management of irrigation water presents a great challenge for the agriculture field. In view of increasing soil water-holding capacity and increasing water-use efficiency, an efficient strategy of managing irrigation water based on formulating highly absorbent polymer-inorganic clay composite (polyacrylic acid-layered double hydroxide; PAA-LDH) was offered. The PAA-LDH composite was synthesized by an incorporation/in situ polymerization technique. Scanning electron microscopy, X-ray analysis and infrared spectroscopy were used to confirm the composite structure. The thermal gravimetric analysis was applied to investigate the polymer thermal stability after the composite formation. The irrigation experiments were conducted in a wooden soil box with a transparent plexiglas side by using a subsurface drip irrigation system. The X-ray patterns and infrared spectra confirmed the incorporation of acrylic acid monomer (AA) into the gallery of LDH. The SEM images emphasized the composite structure of PAA-LDH and indicated its ability to absorb and keep water. The stability of PAA was promoted against the thermal decomposition after the composite formation. The composite structure of PAA-LDH worked as water barrier and secondary water source during the irrigation process. The soil moisture distribution patterns were enhanced after the application of PAA-LDH composites as a soil conditioner.

  10. A multigrid LU-SSOR scheme for approximate Newton iteration applied to the Euler equations

    NASA Technical Reports Server (NTRS)

    Yoon, Seokkwan; Jameson, Antony

    1986-01-01

    A new efficient relaxation scheme in conjunction with a multigrid method is developed for the Euler equations. The LU SSOR scheme is based on a central difference scheme and does not need flux splitting for Newton iteration. Application to transonic flow shows that the new method surpasses the performance of the LU implicit scheme.

  11. An Attempt at Quantifying Factors that Affect Efficiency in the Management of Solid Waste Produced by Commercial Businesses in the City of Tshwane, South Africa

    PubMed Central

    Worku, Yohannes; Muchie, Mammo

    2012-01-01

    Objective. The objective was to investigate factors that affect the efficient management of solid waste produced by commercial businesses operating in the city of Pretoria, South Africa. Methods. Data was gathered from 1,034 businesses. Efficiency in solid waste management was assessed by using a structural time-based model designed for evaluating efficiency as a function of the length of time required to manage waste. Data analysis was performed using statistical procedures such as frequency tables, Pearson's chi-square tests of association, and binary logistic regression analysis. Odds ratios estimated from logistic regression analysis were used for identifying key factors that affect efficiency in the proper disposal of waste. Results. The study showed that 857 of the 1,034 businesses selected for the study (83%) were found to be efficient enough with regards to the proper collection and disposal of solid waste. Based on odds ratios estimated from binary logistic regression analysis, efficiency in the proper management of solid waste was significantly influenced by 4 predictor variables. These 4 influential predictor variables are lack of adherence to waste management regulations, wrong perception, failure to provide customers with enough trash cans, and operation of businesses by employed managers, in a decreasing order of importance. PMID:23209483

  12. Design of modern monitoring systems for efficient control and management of technological processes

    NASA Astrophysics Data System (ADS)

    Abitova, Gulnara; Beisenbi, Mamirbek; Nikulin, Vladimir

    2011-04-01

    Proliferation of new and upgrade of existing industrial technologies is impossible without the development of efficient systems and algorithms of automatic control of technological processes that rely on modern monitoring approaches. Typically, the monitoring tools, which include various sensors and other devices, have to be tightly integrated with automatic control systems of industrial processes to reduce service expenses and downtime, increase capacity and optimize production as a whole. While designing technological and automation lines, it is necessary to carefully select parameters to be monitored such that optimal operation is achieved. At the same time, every step of industrial production has to be monitored to assure that each particular process is properly executed and resources are utilized in an efficient manner. An example presented in this paper is based on an ac electric drive equipped with control and monitoring systems. The result of a properly designed monitoring system is a simplified architecture of the control devices. The overall method can be implemented on the basis of a microprocessor, which offers several advantages including the possibility of designing intelligent control loops, expanding the fault-tolerant range of operation, extending the resource of operation, and coordinating interaction between different systems.

  13. Accuracy and efficiency of detection dogs: a powerful new tool for koala conservation and management.

    PubMed

    Cristescu, Romane H; Foley, Emily; Markula, Anna; Jackson, Gary; Jones, Darryl; Frère, Céline

    2015-01-01

    Accurate data on presence/absence and spatial distribution for fauna species is key to their conservation. Collecting such data, however, can be time consuming, laborious and costly, in particular for fauna species characterised by low densities, large home ranges, cryptic or elusive behaviour. For such species, including koalas (Phascolarctos cinereus), indicators of species presence can be a useful shortcut: faecal pellets (scats), for instance, are widely used. Scat surveys are not without their difficulties and often contain a high false negative rate. We used experimental and field-based trials to investigate the accuracy and efficiency of the first dog specifically trained for koala scats. The detection dog consistently out-performed human-only teams. Off-leash, the dog detection rate was 100%. The dog was also 19 times more efficient than current scat survey methods and 153% more accurate (the dog found koala scats where the human-only team did not). This clearly demonstrates that the use of detection dogs decreases false negatives and survey time, thus allowing for a significant improvement in the quality and quantity of data collection. Given these unequivocal results, we argue that to improve koala conservation, detection dog surveys for koala scats could in the future replace human-only teams.

  14. Accuracy and efficiency of detection dogs: a powerful new tool for koala conservation and management

    PubMed Central

    Cristescu, Romane H.; Foley, Emily; Markula, Anna; Jackson, Gary; Jones, Darryl; Frère, Céline

    2015-01-01

    Accurate data on presence/absence and spatial distribution for fauna species is key to their conservation. Collecting such data, however, can be time consuming, laborious and costly, in particular for fauna species characterised by low densities, large home ranges, cryptic or elusive behaviour. For such species, including koalas (Phascolarctos cinereus), indicators of species presence can be a useful shortcut: faecal pellets (scats), for instance, are widely used. Scat surveys are not without their difficulties and often contain a high false negative rate. We used experimental and field-based trials to investigate the accuracy and efficiency of the first dog specifically trained for koala scats. The detection dog consistently out-performed human-only teams. Off-leash, the dog detection rate was 100%. The dog was also 19 times more efficient than current scat survey methods and 153% more accurate (the dog found koala scats where the human-only team did not). This clearly demonstrates that the use of detection dogs decreases false negatives and survey time, thus allowing for a significant improvement in the quality and quantity of data collection. Given these unequivocal results, we argue that to improve koala conservation, detection dog surveys for koala scats could in the future replace human-only teams. PMID:25666691

  15. Accuracy and efficiency of detection dogs: a powerful new tool for koala conservation and management.

    PubMed

    Cristescu, Romane H; Foley, Emily; Markula, Anna; Jackson, Gary; Jones, Darryl; Frère, Céline

    2015-01-01

    Accurate data on presence/absence and spatial distribution for fauna species is key to their conservation. Collecting such data, however, can be time consuming, laborious and costly, in particular for fauna species characterised by low densities, large home ranges, cryptic or elusive behaviour. For such species, including koalas (Phascolarctos cinereus), indicators of species presence can be a useful shortcut: faecal pellets (scats), for instance, are widely used. Scat surveys are not without their difficulties and often contain a high false negative rate. We used experimental and field-based trials to investigate the accuracy and efficiency of the first dog specifically trained for koala scats. The detection dog consistently out-performed human-only teams. Off-leash, the dog detection rate was 100%. The dog was also 19 times more efficient than current scat survey methods and 153% more accurate (the dog found koala scats where the human-only team did not). This clearly demonstrates that the use of detection dogs decreases false negatives and survey time, thus allowing for a significant improvement in the quality and quantity of data collection. Given these unequivocal results, we argue that to improve koala conservation, detection dog surveys for koala scats could in the future replace human-only teams. PMID:25666691

  16. Influence of nitrogen nutrition management on biomass partitioning and nitrogen use efficiency indices in hydroponically grown potato

    NASA Technical Reports Server (NTRS)

    Goins, Gregory D.; Yorio, Neil C.; Wheeler, Raymond M.

    2004-01-01

    The National Aeronautics and Space Administration (NASA) has been conducting controlled environment research with potatoes (Solanum tuberosum L.) in recirculating nutrient film technique (NFT)-hydroponic systems as a human life support component during long-duration spaceflight. Standard nutrient solution management approaches include constant pH regulation with nitric acid (HNO3) and daily adjustment of electrical conductivity (EC) equivalent to half-strength modified Hoagland's solution, where nitrate (NO3-) is the sole nitrogen (N) source. Although tuber yields have been excellent with such an approach, N use efficiency indices are expected to be low relative to tuber biomass production. Furthermore, the high amount of N used in NFT-hydroponics, typically results in high inedible biomass, which conflicts with the need to minimize system mass, volume, and expenditure of resources for long-duration missions. More effective strategies of N fertilization need to be developed to more closely match N supply with demand of the crop. Hence, the primary objective of this study was to identify the optimal N management regime and plant N requirement to achieve high yields and to avoid inefficient use of N and excess inedible biomass production. In separate 84-day cropping experiments, three N management protocols were tested. Treatments which decreased NO3(-)-N supply indirectly through lowering nutrient solution EC (Expt. I), or disabling pH control, and/or supplying NH4(+)-N (Expt. III) did not significantly benefit tuber yield, but did influence N use efficiency indices. When supplied with an external 7.5 mM NO3(-)-N for the first 42 days after planting (DAP), lowered to 1.0 mM NO3(-)-N during the final 42 days (Expt. II), plants were able to achieve yields on par with plants which received constant 7.5 mM NO3(-)-N (control). By abruptly decreasing N supply at tuber initiation in Expt. II, less N was taken up and accumulated by plants compared to those which received

  17. Influence of nitrogen nutrition management on biomass partitioning and nitrogen use efficiency indices in hydroponically grown potato.

    PubMed

    Goins, Gregory D; Yorio, Neil C; Wheeler, Raymond M

    2004-01-01

    The National Aeronautics and Space Administration (NASA) has been conducting controlled environment research with potatoes (Solanum tuberosum L.) in recirculating nutrient film technique (NFT)-hydroponic systems as a human life support component during long-duration spaceflight. Standard nutrient solution management approaches include constant pH regulation with nitric acid (HNO3) and daily adjustment of electrical conductivity (EC) equivalent to half-strength modified Hoagland's solution, where nitrate (NO3-) is the sole nitrogen (N) source. Although tuber yields have been excellent with such an approach, N use efficiency indices are expected to be low relative to tuber biomass production. Furthermore, the high amount of N used in NFT-hydroponics, typically results in high inedible biomass, which conflicts with the need to minimize system mass, volume, and expenditure of resources for long-duration missions. More effective strategies of N fertilization need to be developed to more closely match N supply with demand of the crop. Hence, the primary objective of this study was to identify the optimal N management regime and plant N requirement to achieve high yields and to avoid inefficient use of N and excess inedible biomass production. In separate 84-day cropping experiments, three N management protocols were tested. Treatments which decreased NO3(-)-N supply indirectly through lowering nutrient solution EC (Expt. I), or disabling pH control, and/or supplying NH4(+)-N (Expt. III) did not significantly benefit tuber yield, but did influence N use efficiency indices. When supplied with an external 7.5 mM NO3(-)-N for the first 42 days after planting (DAP), lowered to 1.0 mM NO3(-)-N during the final 42 days (Expt. II), plants were able to achieve yields on par with plants which received constant 7.5 mM NO3(-)-N (control). By abruptly decreasing N supply at tuber initiation in Expt. II, less N was taken up and accumulated by plants compared to those which received

  18. A context management system for a cost-efficient smart home platform

    NASA Astrophysics Data System (ADS)

    Schneider, J.; Klein, A.; Mannweiler, C.; Schotten, H. D.

    2012-09-01

    This paper presents an overview of state-of-the-art architectures for integrating wireless sensor and actuators networks into the Future Internet. Furthermore, we will address advantages and disadvantages of the different architectures. With respect to these criteria, we develop a new architecture overcoming these weaknesses. Our system, called Smart Home Context Management System, will be used for intelligent home utilities, appliances, and electronics and includes physical, logical as well as network context sources within one concept. It considers important aspects and requirements of modern context management systems for smart X applications: plug and play as well as plug and trust capabilities, scalability, extensibility, security, and adaptability. As such, it is able to control roller blinds, heating systems as well as learn, for example, the user's taste w.r.t. to home entertainment (music, videos, etc.). Moreover, Smart Grid applications and Ambient Assisted Living (AAL) functions are applicable. With respect to AAL, we included an Emergency Handling function. It assures that emergency calls (police, ambulance or fire department) are processed appropriately. Our concept is based on a centralized Context Broker architecture, enhanced by a distributed Context Broker system. The goal of this concept is to develop a simple, low-priced, multi-functional, and save architecture affordable for everybody. Individual components of the architecture are well tested. Implementation and testing of the architecture as a whole is in progress.

  19. An improved biometrics-based remote user authentication scheme with user anonymity.

    PubMed

    Khan, Muhammad Khurram; Kumari, Saru

    2013-01-01

    The authors review the biometrics-based user authentication scheme proposed by An in 2012. The authors show that there exist loopholes in the scheme which are detrimental for its security. Therefore the authors propose an improved scheme eradicating the flaws of An's scheme. Then a detailed security analysis of the proposed scheme is presented followed by its efficiency comparison. The proposed scheme not only withstands security problems found in An's scheme but also provides some extra features with mere addition of only two hash operations. The proposed scheme allows user to freely change his password and also provides user anonymity with untraceability. PMID:24350272

  20. An Improved Biometrics-Based Remote User Authentication Scheme with User Anonymity

    PubMed Central

    Kumari, Saru

    2013-01-01

    The authors review the biometrics-based user authentication scheme proposed by An in 2012. The authors show that there exist loopholes in the scheme which are detrimental for its security. Therefore the authors propose an improved scheme eradicating the flaws of An's scheme. Then a detailed security analysis of the proposed scheme is presented followed by its efficiency comparison. The proposed scheme not only withstands security problems found in An's scheme but also provides some extra features with mere addition of only two hash operations. The proposed scheme allows user to freely change his password and also provides user anonymity with untraceability. PMID:24350272