Full-band TDM-OPDMA for OBI-reduced simultaneous multiple access in a single-wavelength optical access network.

PubMed

Jung, Sun-Young; Kim, Chang-Hun; Han, Sang-Kook

2018-05-14

Simultaneous multiple access (MA) within a single wavelength can increase the data rate and split ratio in a passive optical network while optical beat interference (OBI) becomes serious in the uplink. Previous techniques to reduce OBI were limited by their complexity and lack of extendibility; as well, bandwidth allocation among MA signals is needed for single photo diode (PD) detection. We proposed and experimentally demonstrated full-band optical pulse division multiplexing-based MA (OPDMA) in an optical access network, which can effectively reduce OBI with extendibility and fully utilize frequency resources of optical modulator without bandwidth allocation in a single-wavelength MA.

Latin American algorithm for treatment of relapsing-remitting multiple sclerosis using disease-modifying agents.

PubMed

Finkelsztejn, Alessandro; Gabbai, Alberto Alain; Fragoso, Yara Dadalti; Carrá, Adriana; Macías-Islas, Miguel Angel; Arcega-Revilla, Raul; García-Bonitto, Juan; Oehninger-Gatti, Carlos Luis; Orozco-Escobar, Geraldine; Tarulla, Adriana; Vergara, Fernando; Vizcarra, Darwin

2012-10-01

It is estimated that circa 50,000 individuals have relapsing-remitting multiple sclerosis in Latin America. European and North-American algorithms for the treatment of multiple sclerosis do not foresee our regional difficulties and the access of patients to treatment. The Latin American Multiple Sclerosis Forum is an independent and supra-institutional group of experts that has assessed the latest scientific evidence regarding efficacy and safety of disease-modifying treatments. Accesses to treatment and pharmacovigilance programs for each of the eight countries represented at the Forum were also analyzed. A specific set of guidelines based upon evidence-based recommendations was designed for Latin America. Future perspectives of multiple sclerosis treatment were also discussed. The present paper translated an effort from representatives of eight countries discussing a matter that cannot be adapted to our region directly from purely European and North-American guidelines for treatment.

A distributed data base management facility for the CAD/CAM environment

NASA Technical Reports Server (NTRS)

Balza, R. M.; Beaudet, R. W.; Johnson, H. R.

1984-01-01

Current/PAD research in the area of distributed data base management considers facilities for supporting CAD/CAM data management in a heterogeneous network of computers encompassing multiple data base managers supporting a variety of data models. These facilities include coordinated execution of multiple DBMSs to provide for administration of and access to data distributed across them.

Coherent direct sequence optical code multiple access encoding-decoding efficiency versus wavelength detuning.

PubMed

Pastor, D; Amaya, W; García-Olcina, R; Sales, S

2007-07-01

We present a simple theoretical model of and the experimental verification for vanishing of the autocorrelation peak due to wavelength detuning on the coding-decoding process of coherent direct sequence optical code multiple access systems based on a superstructured fiber Bragg grating. Moreover, the detuning vanishing effect has been explored to take advantage of this effect and to provide an additional degree of multiplexing and/or optical code tuning.

Analysis of hybrid subcarrier multiplexing of OCDMA based on single photodiode detection

NASA Astrophysics Data System (ADS)

Ahmad, N. A. A.; Junita, M. N.; Aljunid, S. A.; Rashidi, C. B. M.; Endut, R.

2017-11-01

This paper analyzes the performance of subcarrier multiplexing (SCM) of spectral amplitude coding optical code multiple access (SAC-OCDMA) by applying Recursive Combinatorial (RC) code based on single photodiode detection (SPD). SPD is used in the receiver part to reduce the effect of multiple access interference (MAI) which contributes as a dominant noise in incoherent SAC-OCDMA systems. Results indicate that the SCM OCDMA network performance could be improved by using lower data rates and higher number of weight. Total number of users can also be enhanced by adding lower data rates and higher number of subcarriers.

Securely and Flexibly Sharing a Biomedical Data Management System

PubMed Central

Wang, Fusheng; Hussels, Phillip; Liu, Peiya

2011-01-01

Biomedical database systems need not only to address the issues of managing complex data, but also to provide data security and access control to the system. These include not only system level security, but also instance level access control such as access of documents, schemas, or aggregation of information. The latter is becoming more important as multiple users can share a single scientific data management system to conduct their research, while data have to be protected before they are published or IP-protected. This problem is challenging as users’ needs for data security vary dramatically from one application to another, in terms of who to share with, what resources to be shared, and at what access level. We develop a comprehensive data access framework for a biomedical data management system SciPort. SciPort provides fine-grained multi-level space based access control of resources at not only object level (documents and schemas), but also space level (resources set aggregated in a hierarchy way). Furthermore, to simplify the management of users and privileges, customizable role-based user model is developed. The access control is implemented efficiently by integrating access privileges into the backend XML database, thus efficient queries are supported. The secure access approach we take makes it possible for multiple users to share the same biomedical data management system with flexible access management and high data security. PMID:21625285

Multiple Access Schemes for Lunar Missions

NASA Technical Reports Server (NTRS)

Deutsch, Leslie; Hamkins, Jon; Stocklin, Frank J.

2010-01-01

Two years ago, the NASA Coding, Modulation, and Link Protocol (CMLP) study was completed. The study, led by the authors of this paper, recommended codes, modulation schemes, and desired attributes of link protocols for all space communication links in NASA's future space architecture. Portions of the NASA CMLP team were reassembled to resolve one open issue: the use of multiple access (MA) communication from the lunar surface. The CMLP-MA team analyzed and simulated two candidate multiple access schemes that were identified in the original CMLP study: Code Division MA (CDMA) and Frequency Division MA (FDMA) based on a bandwidth-efficient Continuous Phase Modulation (CPM) with a superimposed Pseudo-Noise (PN) ranging signal (CPM/PN). This paper summarizes the results of the analysis and simulation of the CMLP-MA study and describes the final recommendations.

Electromagnetic interference-aware transmission scheduling and power control for dynamic wireless access in hospital environments.

PubMed

Phunchongharn, Phond; Hossain, Ekram; Camorlinga, Sergio

2011-11-01

We study the multiple access problem for e-Health applications (referred to as secondary users) coexisting with medical devices (referred to as primary or protected users) in a hospital environment. In particular, we focus on transmission scheduling and power control of secondary users in multiple spatial reuse time-division multiple access (STDMA) networks. The objective is to maximize the spectrum utilization of secondary users and minimize their power consumption subject to the electromagnetic interference (EMI) constraints for active and passive medical devices and minimum throughput guarantee for secondary users. The multiple access problem is formulated as a dual objective optimization problem which is shown to be NP-complete. We propose a joint scheduling and power control algorithm based on a greedy approach to solve the problem with much lower computational complexity. To this end, an enhanced greedy algorithm is proposed to improve the performance of the greedy algorithm by finding the optimal sequence of secondary users for scheduling. Using extensive simulations, the tradeoff in performance in terms of spectrum utilization, energy consumption, and computational complexity is evaluated for both the algorithms.

An access technology delivery protocol for children with severe and multiple disabilities: a case demonstration.

PubMed

Mumford, Leslie; Lam, Rachel; Wright, Virginia; Chau, Tom

2014-08-01

This study applied response efficiency theory to create the Access Technology Delivery Protocol (ATDP), a child and family-centred collaborative approach to the implementation of access technologies. We conducted a descriptive, mixed methods case study to demonstrate the ATDP method with a 12-year-old boy with no reliable means of access to an external device. Evaluations of response efficiency, satisfaction, goal attainment, technology use and participation were made after 8 and 16 weeks of training with a custom smile-based access technology. At the 16 week mark, the new access technology offered better response quality; teacher satisfaction was high; average technology usage was 3-4 times per week for up to 1 h each time; switch sensitivity and specificity reached 78% and 64%, respectively, and participation scores increased by 38%. This case supports further development and testing of the ATDP with additional children with multiple or severe disabilities.

A subjective scheduler for subjective dedicated networks

NASA Astrophysics Data System (ADS)

Suherman; Fakhrizal, Said Reza; Al-Akaidi, Marwan

2017-09-01

Multiple access technique is one of important techniques within medium access layer in TCP/IP protocol stack. Each network technology implements the selected access method. Priority can be implemented in those methods to differentiate services. Some internet networks are dedicated for specific purpose. Education browsing or tutorial video accesses are preferred in a library hotspot, while entertainment and sport contents could be subjects of limitation. Current solution may use IP address filter or access list. This paper proposes subjective properties of users or applications are used for priority determination in multiple access techniques. The NS-2 simulator is employed to evaluate the method. A video surveillance network using WiMAX is chosen as the object. Subjective priority is implemented on WiMAX scheduler based on traffic properties. Three different traffic sources from monitoring video: palace, park, and market are evaluated. The proposed subjective scheduler prioritizes palace monitoring video that results better quality, xx dB than the later monitoring spots.

A multiple camera tongue switch for a child with severe spastic quadriplegic cerebral palsy.

PubMed

Leung, Brian; Chau, Tom

2010-01-01

The present study proposed a video-based access technology that facilitated a non-contact tongue protrusion access modality for a 7-year-old boy with severe spastic quadriplegic cerebral palsy (GMFCS level 5). The proposed system featured a centre camera and two peripheral cameras to extend coverage of the frontal face view of this user for longer durations. The child participated in a descriptive case study. The participant underwent 3 months of tongue protrusion training while the multiple camera tongue switch prototype was being prepared. Later, the participant was brought back for five experiment sessions where he worked on a single-switch picture matching activity, using the multiple camera tongue switch prototype in a controlled environment. The multiple camera tongue switch achieved an average sensitivity of 82% and specificity of 80%. In three of the experiment sessions, the peripheral cameras were associated with most of the true positive switch activations. These activations would have been missed by a centre-camera-only setup. The study demonstrated proof-of-concept of a non-contact tongue access modality implemented by a video-based system involving three cameras and colour video processing.

Embedded controller for GEM detector readout system

NASA Astrophysics Data System (ADS)

Zabołotny, Wojciech M.; Byszuk, Adrian; Chernyshova, Maryna; Cieszewski, Radosław; Czarski, Tomasz; Dominik, Wojciech; Jakubowska, Katarzyna L.; Kasprowicz, Grzegorz; Poźniak, Krzysztof; Rzadkiewicz, Jacek; Scholz, Marek

2013-10-01

This paper describes the embedded controller used for the multichannel readout system for the GEM detector. The controller is based on the embedded Mini ITX mainboard, running the GNU/Linux operating system. The controller offers two interfaces to communicate with the FPGA based readout system. FPGA configuration and diagnostics is controlled via low speed USB based interface, while high-speed setup of the readout parameters and reception of the measured data is handled by the PCI Express (PCIe) interface. Hardware access is synchronized by the dedicated server written in C. Multiple clients may connect to this server via TCP/IP network, and different priority is assigned to individual clients. Specialized protocols have been implemented both for low level access on register level and for high level access with transfer of structured data with "msgpack" protocol. High level functionalities have been split between multiple TCP/IP servers for parallel operation. Status of the system may be checked, and basic maintenance may be performed via web interface, while the expert access is possible via SSH server. System was designed with reliability and flexibility in mind.

Phylogeny and evolutionary histories of Pyrus L. revealed by phylogenetic trees and networks based on data from multiple DNA sequences

USDA-ARS?s Scientific Manuscript database

Reconstructing the phylogeny of Pyrus has been difficult due to the wide distribution of the genus and lack of informative data. In this study, we collected 110 accessions representing 25 Pyrus species and constructed both phylogenetic trees and phylogenetic networks based on multiple DNA sequence d...

FD/DAMA Scheme For Mobile/Satellite Communications

NASA Technical Reports Server (NTRS)

Yan, Tsun-Yee; Wang, Charles C.; Cheng, Unjeng; Rafferty, William; Dessouky, Khaled I.

1992-01-01

Integrated-Adaptive Mobile Access Protocol (I-AMAP) proposed to allocate communication channels to subscribers in first-generation MSAT-X mobile/satellite communication network. Based on concept of frequency-division/demand-assigned multiple access (FD/DAMA) where partition of available spectrum adapted to subscribers' demands for service. Requests processed, and competing requests resolved according to channel-access protocol, or free-access tree algorithm described in "Connection Protocol for Mobile/Satellite Communications" (NPO-17735). Assigned spectrum utilized efficiently.

Comparison of a video-based assessment and a multiple stimulus assessment to identify preferred jobs for individuals with significant intellectual disabilities.

PubMed

Horrocks, Erin L; Morgan, Robert L

2009-01-01

The authors compare two methods of identifying job preferences for individuals with significant intellectual disabilities. Three individuals with intellectual disabilities between the ages of 19 and 21 participated in a video-based preference assessment and a multiple stimulus without replacement (MSWO) assessment. Stimulus preference assessment procedures typically involve giving participants access to the selected stimuli to increase the probability that participants will associate the selected choice with the actual stimuli. Although individuals did not have access to the selected stimuli in the video-based assessment, results indicated that both assessments identified the same highest preference job for all participants. Results are discussed in terms of using a video-based assessment to accurately identify job preferences for individuals with developmental disabilities.

Multiple-choice tests stabilize access to marginal knowledge.

PubMed

Cantor, Allison D; Eslick, Andrea N; Marsh, Elizabeth J; Bjork, Robert A; Bjork, Elizabeth Ligon

2015-02-01

Marginal knowledge refers to knowledge that is stored in memory, but is not accessible at a given moment. For example, one might struggle to remember who wrote The Call of the Wild, even if that knowledge is stored in memory. Knowing how best to stabilize access to marginal knowledge is important, given that new learning often requires accessing and building on prior knowledge. While even a single opportunity to restudy marginal knowledge boosts its later accessibility (Berger, Hall, & Bahrick, 1999), in many situations explicit relearning opportunities are not available. Our question is whether multiple-choice tests (which by definition expose the learner to the correct answers) can also serve this function and, if so, how testing compares to restudying given that tests can be particularly powerful learning devices (Roediger & Karpicke, 2006). In four experiments, we found that multiple-choice testing had the power to stabilize access to marginal knowledge, and to do so for at least up to a week. Importantly, such tests did not need to be paired with feedback, although testing was no more powerful than studying. Overall, the results support the idea that one's knowledge base is unstable, with individual pieces of information coming in and out of reach. The present findings have implications for a key educational challenge: ensuring that students have continuing access to information they have learned.

From continuing education to personal digital assistants: what do physical therapists need to support evidence-based practice in stroke management?

PubMed

Salbach, Nancy M; Veinot, Paula; Jaglal, Susan B; Bayley, Mark; Rolfe, Danielle

2011-08-01

Understanding how to structure educational interventions and resources to facilitate physical therapists' application of the research literature is required. The objective of this study was to explore physical therapists' preferences for strategies to facilitate their access to, evaluation and implementation of the stroke research literature in clinical practice. In-depth, qualitative telephone interviews were conducted with 23 physical therapists who treat people with stroke in Ontario, Canada and who had participated in a previous survey on evidence-based practice. Data were analysed using a constant comparative approach to identify emergent themes. Participants preferred online access to research summaries or systematic reviews to save time to filter and critique research articles. To enable access in the workplace, an acceptable computer-to-staff ratio, permission to access web sites and protected work time were suggested. Participants considered personal digital assistants as excellent tools for quick access to online resources but were unsure of their advantage over a desktop computer. Therapists favoured use of non-technical language, glossaries of research terms and quality ratings of studies to ease understanding and appraisal. Teleconferencing or videoconferencing overcame geographical but not scheduling barriers to accessing education. To achieve behaviour change in clinical practice, therapists preferred multiple interactive, face-to-face education sessions in a group format, with opportunities for case-based learning and practice of new skills. Physical therapists prefer technology-assisted access to resources and education and favour attending multiple interactive, expert-facilitated education sessions incorporating opportunities for case-based learning and practice of new skills to change behaviour related to evidence-based practice. © 2010 Blackwell Publishing Ltd.

High security chaotic multiple access scheme for visible light communication systems with advanced encryption standard interleaving

NASA Astrophysics Data System (ADS)

Qiu, Junchao; Zhang, Lin; Li, Diyang; Liu, Xingcheng

2016-06-01

Chaotic sequences can be applied to realize multiple user access and improve the system security for a visible light communication (VLC) system. However, since the map patterns of chaotic sequences are usually well known, eavesdroppers can possibly derive the key parameters of chaotic sequences and subsequently retrieve the information. We design an advanced encryption standard (AES) interleaving aided multiple user access scheme to enhance the security of a chaotic code division multiple access-based visible light communication (C-CDMA-VLC) system. We propose to spread the information with chaotic sequences, and then the spread information is interleaved by an AES algorithm and transmitted over VLC channels. Since the computation complexity of performing inverse operations to deinterleave the information is high, the eavesdroppers in a high speed VLC system cannot retrieve the information in real time; thus, the system security will be enhanced. Moreover, we build a mathematical model for the AES-aided VLC system and derive the theoretical information leakage to analyze the system security. The simulations are performed over VLC channels, and the results demonstrate the effectiveness and high security of our presented AES interleaving aided chaotic CDMA-VLC system.

Performance Analysis of a New Coded TH-CDMA Scheme in Dispersive Infrared Channel with Additive Gaussian Noise

NASA Astrophysics Data System (ADS)

Hamdi, Mazda; Kenari, Masoumeh Nasiri

2013-06-01

We consider a time-hopping based multiple access scheme introduced in [1] for communication over dispersive infrared links, and evaluate its performance for correlator and matched filter receivers. In the investigated time-hopping code division multiple access (TH-CDMA) method, the transmitter benefits a low rate convolutional encoder. In this method, the bit interval is divided into Nc chips and the output of the encoder along with a PN sequence assigned to the user determines the position of the chip in which the optical pulse is transmitted. We evaluate the multiple access performance of the system for correlation receiver considering background noise which is modeled as White Gaussian noise due to its large intensity. For the correlation receiver, the results show that for a fixed processing gain, at high transmit power, where the multiple access interference has the dominant effect, the performance improves by the coding gain. But at low transmit power, in which the increase of coding gain leads to the decrease of the chip time, and consequently, to more corruption due to the channel dispersion, there exists an optimum value for the coding gain. However, for the matched filter, the performance always improves by the coding gain. The results show that the matched filter receiver outperforms the correlation receiver in the considered cases. Our results show that, for the same bandwidth and bit rate, the proposed system excels other multiple access techniques, like conventional CDMA and time hopping scheme.

An Access Control and Trust Management Framework for Loosely-Coupled Multidomain Environments

ERIC Educational Resources Information Center

Zhang, Yue

2010-01-01

Multidomain environments where multiple organizations interoperate with each other are becoming a reality as can be seen in emerging Internet-based enterprise applications. Access control to ensure secure interoperation in such an environment is a crucial challenge. A multidomain environment can be categorized as "tightly-coupled" and…

Research on a Queue Scheduling Algorithm in Wireless Communications Network

NASA Astrophysics Data System (ADS)

Yang, Wenchuan; Hu, Yuanmei; Zhou, Qiancai

This paper proposes a protocol QS-CT, Queue Scheduling Mechanism based on Multiple Access in Ad hoc net work, which adds queue scheduling mechanism to RTS-CTS-DATA using multiple access protocol. By endowing different queues different scheduling mechanisms, it makes networks access to the channel much more fairly and effectively, and greatly enhances the performance. In order to observe the final performance of the network with QS-CT protocol, we simulate it and compare it with MACA/C-T without QS-CT protocol. Contrast to MACA/C-T, the simulation result shows that QS-CT has greatly improved the throughput, delay, rate of packets' loss and other key indicators.

Concept and implementation of the Globalstar mobile satellite system

NASA Technical Reports Server (NTRS)

Schindall, Joel

1995-01-01

Globalstar is a satellite-based mobile communications system which provides quality wireless communications (voice and/or data) anywhere in the world except the polar regions. The Globalstar system concept is based upon technological advancements in Low Earth Orbit (LEO) satellite technology and in cellular telephone technology, including the commercial application of Code Division Multiple Access (CDMA) technologies. The Globalstar system uses elements of CDMA and Frequency Division Multiple Access (FDMA), combined with satellite Multiple Beam Antenna (MBA) technology and advanced variable-rate vocoder technology to arrive at one of the most efficient modulation and multiple access systems ever proposed for a satellite communications system. The technology used in Globalstar includes the following techniques in obtaining high spectral efficiency and affordable cost per channel: (1) CDMA modulation with efficient power control; (2) high efficiency vocoder with voice activity factor; (3) spot beam antenna for increased gain and frequency reuse; (4) weighted satellite antenna gain for broad geographic coverage; (5) multisatellite user links (diversity) to enhance communications reliability; and (6) soft hand-off between beams and satellites. Initial launch is scheduled in 1997 and the system is scheduled to be operational in 1998. The Globalstar system utilizes frequencies in L-, S- and C-bands which have the potential to offer worldwide availability with authorization by the appropriate regulatory agencies.

The NCAR Research Data Archive's Hybrid Approach for Data Discovery and Access

NASA Astrophysics Data System (ADS)

Schuster, D.; Worley, S. J.

2013-12-01

The NCAR Research Data Archive (RDA http://rda.ucar.edu) maintains a variety of data discovery and access capabilities for it's 600+ dataset collections to support the varying needs of a diverse user community. In-house developed and standards-based community tools offer services to more than 10,000 users annually. By number of users the largest group is external and access the RDA through web based protocols; the internal NCAR HPC users are fewer in number, but typically access more data volume. This paper will detail the data discovery and access services maintained by the RDA to support both user groups, and show metrics that illustrate how the community is using the services. The distributed search capability enabled by standards-based community tools, such as Geoportal and an OAI-PMH access point that serves multiple metadata standards, provide pathways for external users to initially discover RDA holdings. From here, in-house developed web interfaces leverage primary discovery level metadata databases that support keyword and faceted searches. Internal NCAR HPC users, or those familiar with the RDA, may go directly to the dataset collection of interest and refine their search based on rich file collection metadata. Multiple levels of metadata have proven to be invaluable for discovery within terabyte-sized archives composed of many atmospheric or oceanic levels, hundreds of parameters, and often numerous grid and time resolutions. Once users find the data they want, their access needs may vary as well. A THREDDS data server running on targeted dataset collections enables remote file access through OPENDAP and other web based protocols primarily for external users. In-house developed tools give all users the capability to submit data subset extraction and format conversion requests through scalable, HPC based delayed mode batch processing. Users can monitor their RDA-based data processing progress and receive instructions on how to access the data when it is ready. External users are provided with RDA server generated scripts to download the resulting request output. Similarly they can download native dataset collection files or partial files using Wget or cURL based scripts supplied by the RDA server. Internal users can access the resulting request output or native dataset collection files directly from centralized file systems.

Barriers to the Accessibility and Continuity of Health-Care Services in People with Multiple Sclerosis

PubMed Central

Bishop, Malachy; Pionke, J.J.; Strauser, David; Santens, Ryan L.

2017-01-01

Background: Individuals with multiple sclerosis (MS) face a range of barriers to accessing and using health-care services. The aim of this review was to identify specific barriers to accessing and using health-care services based on a continuum of the health-care delivery system. Methods: Literature searches were conducted in the PubMed, PsycINFO, CINAHL, and Web of Science databases. The following terms were searched as subject headings, key words, or abstracts: health care, access, barriers, physical disability, and multiple sclerosis. The literature search produced 361 potentially relevant citations. After screening titles, abstracts, and citations, eight citations were selected for full-text review. Results: Health-care barriers were divided into three continuous phases of receiving health care. In the before-visit phase, the most commonly identified barrier was transportation. In the during-visit phase, communication quality was the major concern. In the after-visit phase, discontinued referral was the major barrier encountered. Conclusions: There are multiple interrelated barriers to accessing and using health-care services along the health-care delivery continuum for people with MS and its associated physical disabilities, ranging from complex and long-recognized barriers that will likely require extended advocacy to create policy changes to issues that can and should be addressed through relatively minor changes in health-care delivery practices, improved care coordination, and increased provider awareness, education, and responsiveness to patients' needs. PMID:29270089

The US EPA CompTox Chemistry Dashboard as a source of data to fill data gaps for chemical sources of risk

EPA Science Inventory

Chemical risk assessment is both time-consuming and difficult because it requires the assembly of data for chemicals generally distributed across multiple sources. The US EPA CompTox Chemistry Dashboard is a publicly accessible web-based application providing access to various da...

Strategies for Disseminating Information on Biomedical Research on Autism to Hispanic Parents

ERIC Educational Resources Information Center

Lajonchere, Clara M.; Wheeler, Barbara Y.; Valente, Thomas W.; Kreutzer, Cary; Munson, Aron; Narayanan, Shrikanth; Kazemzadeh, Abe; Cruz, Roxana; Martinez, Irene; Schrager, Sheree M.; Schweitzer, Lisa; Chklovski, Tara; Hwang, Darryl

2016-01-01

Low income Hispanic families experience multiple barriers to accessing evidence-based information on Autism Spectrum Disorders (ASD). This study utilized a mixed-strategy intervention to create access to information in published bio-medical research articles on ASD by distilling the content into parent-friendly English- and Spanish-language ASD…

Overview of Sparse Graph for Multiple Access in Future Mobile Networks

NASA Astrophysics Data System (ADS)

Lei, Jing; Li, Baoguo; Li, Erbao; Gong, Zhenghui

2017-10-01

Multiple access via sparse graph, such as low density signature (LDS) and sparse code multiple access (SCMA), is a promising technique for future wireless communications. This survey presents an overview of the developments in this burgeoning field, including transmitter structures, extrinsic information transform (EXIT) chart analysis and comparisons with existing multiple access techniques. Such technique enables multiple access under overloaded conditions to achieve a satisfactory performance. Message passing algorithm is utilized for multi-user detection in the receiver, and structures of the sparse graph are illustrated in detail. Outlooks and challenges of this technique are also presented.

Microprocessor-controlled, wide-range streak camera

DOE Office of Scientific and Technical Information (OSTI.GOV)

Amy E. Lewis, Craig Hollabaugh

Bechtel Nevada/NSTec recently announced deployment of their fifth generation streak camera. This camera incorporates many advanced features beyond those currently available for streak cameras. The arc-resistant driver includes a trigger lockout mechanism, actively monitors input trigger levels, and incorporates a high-voltage fault interrupter for user safety and tube protection. The camera is completely modular and may deflect over a variable full-sweep time of 15 nanoseconds to 500 microseconds. The camera design is compatible with both large- and small-format commercial tubes from several vendors. The embedded microprocessor offers Ethernet connectivity, and XML [extensible markup language]-based configuration management with non-volatile parameter storagemore » using flash-based storage media. The camera’s user interface is platform-independent (Microsoft Windows, Unix, Linux, Macintosh OSX) and is accessible using an AJAX [asynchronous Javascript and XML]-equipped modem browser, such as Internet Explorer 6, Firefox, or Safari. User interface operation requires no installation of client software or browser plug-in technology. Automation software can also access the camera configuration and control using HTTP [hypertext transfer protocol]. The software architecture supports multiple-simultaneous clients, multiple cameras, and multiple module access with a standard browser. The entire user interface can be customized.« less

Microprocessor-controlled wide-range streak camera

NASA Astrophysics Data System (ADS)

Lewis, Amy E.; Hollabaugh, Craig

2006-08-01

Bechtel Nevada/NSTec recently announced deployment of their fifth generation streak camera. This camera incorporates many advanced features beyond those currently available for streak cameras. The arc-resistant driver includes a trigger lockout mechanism, actively monitors input trigger levels, and incorporates a high-voltage fault interrupter for user safety and tube protection. The camera is completely modular and may deflect over a variable full-sweep time of 15 nanoseconds to 500 microseconds. The camera design is compatible with both large- and small-format commercial tubes from several vendors. The embedded microprocessor offers Ethernet connectivity, and XML [extensible markup language]-based configuration management with non-volatile parameter storage using flash-based storage media. The camera's user interface is platform-independent (Microsoft Windows, Unix, Linux, Macintosh OSX) and is accessible using an AJAX [asynchronous Javascript and XML]-equipped modem browser, such as Internet Explorer 6, Firefox, or Safari. User interface operation requires no installation of client software or browser plug-in technology. Automation software can also access the camera configuration and control using HTTP [hypertext transfer protocol]. The software architecture supports multiple-simultaneous clients, multiple cameras, and multiple module access with a standard browser. The entire user interface can be customized.

Fiber-Bragg-Grating-Based Optical Code-Division Multiple Access Passive Optical Network Using Dual-Baseband Modulation Scheme

NASA Astrophysics Data System (ADS)

Lin, Wen-Piao; Wu, He-Long

2005-08-01

We propose a fiber-Bragg-grating (FBG)-based optical code-division multiple access passive optical network (OCDMA-PON) using a dual-baseband modulation scheme. A mathematical model is developed to study the performance of this scheme. According to the analyzed results, this scheme can allow a tolerance of the spectral power distortion (SPD) ratio of 25% with a bit error rate (BER) of 10-9 when the modified pseudorandom noise (PN) code length is 16. Moreover, we set up a simulated system to evaluate the baseband and radio frequency (RF) band transmission characteristics. The simulation results demonstrate that our proposed OCDMA-PON can provide a cost-effective and scalable fiber-to-the-home solution.

A Simple Exact Error Rate Analysis for DS-CDMA with Arbitrary Pulse Shape in Flat Nakagami Fading

NASA Astrophysics Data System (ADS)

Rahman, Mohammad Azizur; Sasaki, Shigenobu; Kikuchi, Hisakazu; Harada, Hiroshi; Kato, Shuzo

A simple exact error rate analysis is presented for random binary direct sequence code division multiple access (DS-CDMA) considering a general pulse shape and flat Nakagami fading channel. First of all, a simple model is developed for the multiple access interference (MAI). Based on this, a simple exact expression of the characteristic function (CF) of MAI is developed in a straight forward manner. Finally, an exact expression of error rate is obtained following the CF method of error rate analysis. The exact error rate so obtained can be much easily evaluated as compared to the only reliable approximate error rate expression currently available, which is based on the Improved Gaussian Approximation (IGA).

Hierarchy Bayesian model based services awareness of high-speed optical access networks

NASA Astrophysics Data System (ADS)

Bai, Hui-feng

2018-03-01

As the speed of optical access networks soars with ever increasing multiple services, the service-supporting ability of optical access networks suffers greatly from the shortage of service awareness. Aiming to solve this problem, a hierarchy Bayesian model based services awareness mechanism is proposed for high-speed optical access networks. This approach builds a so-called hierarchy Bayesian model, according to the structure of typical optical access networks. Moreover, the proposed scheme is able to conduct simple services awareness operation in each optical network unit (ONU) and to perform complex services awareness from the whole view of system in optical line terminal (OLT). Simulation results show that the proposed scheme is able to achieve better quality of services (QoS), in terms of packet loss rate and time delay.

An Effective Massive Sensor Network Data Access Scheme Based on Topology Control for the Internet of Things.

PubMed

Yi, Meng; Chen, Qingkui; Xiong, Neal N

2016-11-03

This paper considers the distributed access and control problem of massive wireless sensor networks' data access center for the Internet of Things, which is an extension of wireless sensor networks and an element of its topology structure. In the context of the arrival of massive service access requests at a virtual data center, this paper designs a massive sensing data access and control mechanism to improve the access efficiency of service requests and makes full use of the available resources at the data access center for the Internet of things. Firstly, this paper proposes a synergistically distributed buffer access model, which separates the information of resource and location. Secondly, the paper divides the service access requests into multiple virtual groups based on their characteristics and locations using an optimized self-organizing feature map neural network. Furthermore, this paper designs an optimal scheduling algorithm of group migration based on the combination scheme between the artificial bee colony algorithm and chaos searching theory. Finally, the experimental results demonstrate that this mechanism outperforms the existing schemes in terms of enhancing the accessibility of service requests effectively, reducing network delay, and has higher load balancing capacity and higher resource utility rate.

A Hybrid TDMA/CSMA-Based Wireless Sensor and Data Transmission Network for ORS Intra-Microsatellite Applications

PubMed Central

Wang, Long; Liu, Yong; Yin, Zengshan

2018-01-01

To achieve launch-on-demand for Operationally Responsive Space (ORS) missions, in this article, an intra-satellite wireless network (ISWN) is presented. It provides a wireless and modularized scheme for intra-spacecraft sensing and data buses. By removing the wired data bus, the commercial off-the-shelf (COTS) based wireless modular architecture will reduce both the volume and weight of the satellite platform, thus achieving rapid design and cost savings in development and launching. Based on the on-orbit data demand analysis, a hybrid time division multiple access/carrier sense multiple access (TDMA/CSMA) protocol is proposed. It includes an improved clear channel assessment (CCA) mechanism and a traffic adaptive slot allocation method. To analyze the access process, a Markov model is constructed. Then a detailed calculation is given in which the unsaturated cases are considered. Through simulations, the proposed protocol is proved to commendably satisfy the demands and performs better than existing schemes. It helps to build a full-wireless satellite instead of the current wired ones, and will contribute to provide dynamic space capabilities for ORS missions. PMID:29757243

A Hybrid TDMA/CSMA-Based Wireless Sensor and Data Transmission Network for ORS Intra-Microsatellite Applications.

PubMed

Wang, Long; Liu, Yong; Yin, Zengshan

2018-05-12

To achieve launch-on-demand for Operationally Responsive Space (ORS) missions, in this article, an intra-satellite wireless network (ISWN) is presented. It provides a wireless and modularized scheme for intra-spacecraft sensing and data buses. By removing the wired data bus, the commercial off-the-shelf (COTS) based wireless modular architecture will reduce both the volume and weight of the satellite platform, thus achieving rapid design and cost savings in development and launching. Based on the on-orbit data demand analysis, a hybrid time division multiple access/carrier sense multiple access (TDMA/CSMA) protocol is proposed. It includes an improved clear channel assessment (CCA) mechanism and a traffic adaptive slot allocation method. To analyze the access process, a Markov model is constructed. Then a detailed calculation is given in which the unsaturated cases are considered. Through simulations, the proposed protocol is proved to commendably satisfy the demands and performs better than existing schemes. It helps to build a full-wireless satellite instead of the current wired ones, and will contribute to provide dynamic space capabilities for ORS missions.

Using dBASE II for Bibliographic Files.

ERIC Educational Resources Information Center

Sullivan, Jeanette

1985-01-01

Describes use of a database management system (dBASE II, produced by Ashton-Tate), noting best features and disadvantages. Highlights include data entry, multiple access points available, training requirements, use of dBASE for a bibliographic application, auxiliary software, and dBASE updates. Sample searches, auxiliary programs, and requirements…

A carrier sensed multiple access protocol for high data base rate ring networks

NASA Technical Reports Server (NTRS)

Foudriat, E. C.; Maly, Kurt J.; Overstreet, C. Michael; Khanna, S.; Paterra, Frank

1990-01-01

The results of the study of a simple but effective media access protocol for high data rate networks are presented. The protocol is based on the fact that at high data rates networks can contain multiple messages simultaneously over their span, and that in a ring, nodes used to detect the presence of a message arriving from the immediate upstream neighbor. When an incoming signal is detected, the node must either abort or truncate a message it is presently sending. Thus, the protocol with local carrier sensing and multiple access is designated CSMA/RN. The performance of CSMA/RN with TTattempt and truncate is studied using analytic and simulation models. Three performance factors, wait or access time, service time and response or end-to-end travel time are presented. The service time is basically a function of the network rate, it changes by a factor of 1 between no load and full load. Wait time, which is zero for no load, remains small for load factors up to 70 percent of full load. Response time, which adds travel time while on the network to wait and service time, is mainly a function of network length, especially for longer distance networks. Simulation results are shown for CSMA/RN where messages are removed at the destination. A wide range of local and metropolitan area network parameters including variations in message size, network length, and node count are studied. Finally, a scaling factor based upon the ratio of message to network length demonstrates that the results, and hence, the CSMA/RN protocol, are applicable to wide area networks.

Generation-based memory synchronization in a multiprocessor system with weakly consistent memory accesses

DOEpatents

Ohmacht, Martin

2017-08-15

In a multiprocessor system, a central memory synchronization module coordinates memory synchronization requests responsive to memory access requests in flight, a generation counter, and a reclaim pointer. The central module communicates via point-to-point communication. The module includes a global OR reduce tree for each memory access requesting device, for detecting memory access requests in flight. An interface unit is implemented associated with each processor requesting synchronization. The interface unit includes multiple generation completion detectors. The generation count and reclaim pointer do not pass one another.

Generation-based memory synchronization in a multiprocessor system with weakly consistent memory accesses

DOEpatents

Ohmacht, Martin

2014-09-09

In a multiprocessor system, a central memory synchronization module coordinates memory synchronization requests responsive to memory access requests in flight, a generation counter, and a reclaim pointer. The central module communicates via point-to-point communication. The module includes a global OR reduce tree for each memory access requesting device, for detecting memory access requests in flight. An interface unit is implemented associated with each processor requesting synchronization. The interface unit includes multiple generation completion detectors. The generation count and reclaim pointer do not pass one another.

Construction of a virtual EPR and automated contextual linkage to multiple sources of support information on the Oxford Clinical Intranet.

PubMed

Kay, J D; Nurse, D

1999-01-01

We have used internet-standard tools to provide access for clinicians to the components of the electronic patient record held on multiple remote disparate systems. Through the same interface we have provided access to multiple knowledgebases, some written locally and others published elsewhere. We have developed linkage between these two types of information which removes the need for the user to drill down into each knowledgebase to search for relevant information. This approach may help in the implementation of evidence-based practice. The major problems appear to be semantic rather than technological. The intranet was developed at low cost and is now in routine use. This approach appears to be transferable across systems and organisations.

Video Modeling and Observational Learning to Teach Gaming Access to Students with ASD

ERIC Educational Resources Information Center

Spriggs, Amy D.; Gast, David L.; Knight, Victoria F.

2016-01-01

The purpose of this study was to evaluate both video modeling and observational learning to teach age-appropriate recreation and leisure skills (i.e., accessing video games) to students with autism spectrum disorder. Effects of video modeling were evaluated via a multiple probe design across participants and criteria for mastery were based on…

Low- and High-Achieving Sixth-Grade Students' Access to Participation during Mathematics Discourse

ERIC Educational Resources Information Center

Lack, Brian; Swars, Susan Lee; Meyers, Barbara

2014-01-01

A descriptive, holistic, multiple-case methodology was applied to examine the nature of participation in discourse of two low- and two high-achieving grade 6 students while solving mathematical tasks in a standards-based classroom. Data collected via classroom observations and student interviews were analyzed through a multiple-cycle coding…

Optical multiple access techniques for on-board routing

NASA Technical Reports Server (NTRS)

Mendez, Antonio J.; Park, Eugene; Gagliardi, Robert M.

1992-01-01

The purpose of this research contract was to design and analyze an optical multiple access system, based on Code Division Multiple Access (CDMA) techniques, for on board routing applications on a future communication satellite. The optical multiple access system was to effect the functions of a circuit switch under the control of an autonomous network controller and to serve eight (8) concurrent users at a point to point (port to port) data rate of 180 Mb/s. (At the start of this program, the bit error rate requirement (BER) was undefined, so it was treated as a design variable during the contract effort.) CDMA was selected over other multiple access techniques because it lends itself to bursty, asynchronous, concurrent communication and potentially can be implemented with off the shelf, reliable optical transceivers compatible with long term unattended operations. Temporal, temporal/spatial hybrids and single pulse per row (SPR, sometimes termed 'sonar matrices') matrix types of CDMA designs were considered. The design, analysis, and trade offs required by the statement of work selected a temporal/spatial CDMA scheme which has SPR properties as the preferred solution. This selected design can be implemented for feasibility demonstration with off the shelf components (which are identified in the bill of materials of the contract Final Report). The photonic network architecture of the selected design is based on M(8,4,4) matrix codes. The network requires eight multimode laser transmitters with laser pulses of 0.93 ns operating at 180 Mb/s and 9-13 dBm peak power, and 8 PIN diode receivers with sensitivity of -27 dBm for the 0.93 ns pulses. The wavelength is not critical, but 830 nm technology readily meets the requirements. The passive optical components of the photonic network are all multimode and off the shelf. Bit error rate (BER) computations, based on both electronic noise and intercode crosstalk, predict a raw BER of (10 exp -3) when all eight users are communicating concurrently. If better BER performance is required, then error correction codes (ECC) using near term electronic technology can be used. For example, the M(8,4,4) optical code together with Reed-Solomon (54,38,8) encoding provides a BER of better than (10 exp -11). The optical transceiver must then operate at 256 Mb/s with pulses of 0.65 ns because the 'bits' are now channel symbols.

Heuristic query optimization for query multiple table and multiple clausa on mobile finance application

NASA Astrophysics Data System (ADS)

Indrayana, I. N. E.; P, N. M. Wirasyanti D.; Sudiartha, I. KG

2018-01-01

Mobile application allow many users to access data from the application without being limited to space, space and time. Over time the data population of this application will increase. Data access time will cause problems if the data record has reached tens of thousands to millions of records.The objective of this research is to maintain the performance of data execution for large data records. One effort to maintain data access time performance is to apply query optimization method. The optimization used in this research is query heuristic optimization method. The built application is a mobile-based financial application using MySQL database with stored procedure therein. This application is used by more than one business entity in one database, thus enabling rapid data growth. In this stored procedure there is an optimized query using heuristic method. Query optimization is performed on a “Select” query that involves more than one table with multiple clausa. Evaluation is done by calculating the average access time using optimized and unoptimized queries. Access time calculation is also performed on the increase of population data in the database. The evaluation results shown the time of data execution with query heuristic optimization relatively faster than data execution time without using query optimization.

Target Acquisition Performance of a Satellite Based Multiple Access Surveillance System

DOT National Transportation Integrated Search

1975-03-01

A quantitative description of the detection performance of a satellite-based surveillance system is presented. This system is one which has been proposed for CONUS coverage in an advanced air traffic control system. In addition, the computer program ...

Machine learning research 1989-90

NASA Technical Reports Server (NTRS)

Porter, Bruce W.; Souther, Arthur

1990-01-01

Multifunctional knowledge bases offer a significant advance in artificial intelligence because they can support numerous expert tasks within a domain. As a result they amortize the costs of building a knowledge base over multiple expert systems and they reduce the brittleness of each system. Due to the inevitable size and complexity of multifunctional knowledge bases, their construction and maintenance require knowledge engineering and acquisition tools that can automatically identify interactions between new and existing knowledge. Furthermore, their use requires software for accessing those portions of the knowledge base that coherently answer questions. Considerable progress was made in developing software for building and accessing multifunctional knowledge bases. A language was developed for representing knowledge, along with software tools for editing and displaying knowledge, a machine learning program for integrating new information into existing knowledge, and a question answering system for accessing the knowledge base.

Distributed Storage Algorithm for Geospatial Image Data Based on Data Access Patterns.

PubMed

Pan, Shaoming; Li, Yongkai; Xu, Zhengquan; Chong, Yanwen

2015-01-01

Declustering techniques are widely used in distributed environments to reduce query response time through parallel I/O by splitting large files into several small blocks and then distributing those blocks among multiple storage nodes. Unfortunately, however, many small geospatial image data files cannot be further split for distributed storage. In this paper, we propose a complete theoretical system for the distributed storage of small geospatial image data files based on mining the access patterns of geospatial image data using their historical access log information. First, an algorithm is developed to construct an access correlation matrix based on the analysis of the log information, which reveals the patterns of access to the geospatial image data. Then, a practical heuristic algorithm is developed to determine a reasonable solution based on the access correlation matrix. Finally, a number of comparative experiments are presented, demonstrating that our algorithm displays a higher total parallel access probability than those of other algorithms by approximately 10-15% and that the performance can be further improved by more than 20% by simultaneously applying a copy storage strategy. These experiments show that the algorithm can be applied in distributed environments to help realize parallel I/O and thereby improve system performance.

Optical multidimensional multiple access(O-MDMA): a new concept for free-space laser communication based on photonic mixer devices

NASA Astrophysics Data System (ADS)

Hess, Holger; Albrecht, Martin; Grothof, Markus; Hussmann, Stephan; Schwarte, Rudolf

2004-01-01

Working on optical distance measurement a new optical correlator was developed at the Institute for Data Processing of the University of Siegen in the last years. The so called Photonic Mixer Device (PMD), to be meant originally for laser ranging systems, offers a lot of advantages for wireless optical data communication like high speed spatial light demodulation up to the GHz range and inherent backlight suppression. This contribution describes the application of such PMDs in a free space interconnect based on the principle of Multi Dimensional Multiple Access (MDMA) and the advantages of this new approach, starting from the MDMA principle and followed by the fundamental functionality of PMDs. After that an Optical MDMA (O-MDMA) demonstrator and first measurement results will be presented.

Visualization of Multi-mission Astronomical Data with ESASky

NASA Astrophysics Data System (ADS)

Baines, Deborah; Giordano, Fabrizio; Racero, Elena; Salgado, Jesús; López Martí, Belén; Merín, Bruno; Sarmiento, María-Henar; Gutiérrez, Raúl; Ortiz de Landaluce, Iñaki; León, Ignacio; de Teodoro, Pilar; González, Juan; Nieto, Sara; Segovia, Juan Carlos; Pollock, Andy; Rosa, Michael; Arviset, Christophe; Lennon, Daniel; O'Mullane, William; de Marchi, Guido

2017-02-01

ESASky is a science-driven discovery portal to explore the multi-wavelength sky and visualize and access multiple astronomical archive holdings. The tool is a web application that requires no prior knowledge of any of the missions involved and gives users world-wide simplified access to the highest-level science data products from multiple astronomical space-based astronomy missions plus a number of ESA source catalogs. The first public release of ESASky features interfaces for the visualization of the sky in multiple wavelengths, the visualization of query results summaries, and the visualization of observations and catalog sources for single and multiple targets. This paper describes these features within ESASky, developed to address use cases from the scientific community. The decisions regarding the visualization of large amounts of data and the technologies used were made to maximize the responsiveness of the application and to keep the tool as useful and intuitive as possible.

Identifying Opportunities for Decision Support Systems in Support of Regional Resource Use Planning: An Approach Through Soft Systems Methodology.

PubMed

Zhu; Dale

2000-10-01

/ Regional resource use planning relies on key regional stakeholder groups using and having equitable access to appropriate social, economic, and environmental information and assessment tools. Decision support systems (DSS) can improve stakeholder access to such information and analysis tools. Regional resource use planning, however, is a complex process involving multiple issues, multiple assessment criteria, multiple stakeholders, and multiple values. There is a need for an approach to DSS development that can assist in understanding and modeling complex problem situations in regional resource use so that areas where DSSs could provide effective support can be identified, and the user requirements can be well established. This paper presents an approach based on the soft systems methodology for identifying DSS opportunities for regional resource use planning, taking the Central Highlands Region of Queensland, Australia, as a case study.

Lynx web services for annotations and systems analysis of multi-gene disorders.

PubMed

Sulakhe, Dinanath; Taylor, Andrew; Balasubramanian, Sandhya; Feng, Bo; Xie, Bingqing; Börnigen, Daniela; Dave, Utpal J; Foster, Ian T; Gilliam, T Conrad; Maltsev, Natalia

2014-07-01

Lynx is a web-based integrated systems biology platform that supports annotation and analysis of experimental data and generation of weighted hypotheses on molecular mechanisms contributing to human phenotypes and disorders of interest. Lynx has integrated multiple classes of biomedical data (genomic, proteomic, pathways, phenotypic, toxicogenomic, contextual and others) from various public databases as well as manually curated data from our group and collaborators (LynxKB). Lynx provides tools for gene list enrichment analysis using multiple functional annotations and network-based gene prioritization. Lynx provides access to the integrated database and the analytical tools via REST based Web Services (http://lynx.ci.uchicago.edu/webservices.html). This comprises data retrieval services for specific functional annotations, services to search across the complete LynxKB (powered by Lucene), and services to access the analytical tools built within the Lynx platform. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

Why Atens Enjoy Enhanced Accessibility for Human Space Flight

NASA Technical Reports Server (NTRS)

Barbee, Brent W.; Adamo, Daniel R.

2011-01-01

Near-Earth objects can be grouped into multiple orbit classifications, among them being the Aten group, whose members have orbits crossing Earth's with semi-major axes less than 1 astronomical unit. Atens comprise well under 10% of known near-Earth objects. This is in dramatic contrast to results from recent human space flight near-Earth object accessibility studies, where the most favorable known destinations are typically almost 50% Atens. Geocentric dynamics explain this enhanced Aten accessibility and lead to an understanding of where the most accessible near-Earth objects reside. Without a comprehensive space-based survey, however, highly accessible Atens will remain largely unknown.

Channel Access in Erlang

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nicklaus, Dennis J.

2013-10-13

We have developed an Erlang language implementation of the Channel Access protocol. Included are low-level functions for encoding and decoding Channel Access protocol network packets as well as higher level functions for monitoring or setting EPICS process variables. This provides access to EPICS process variables for the Fermilab Acnet control system via our Erlang-based front-end architecture without having to interface to C/C++ programs and libraries. Erlang is a functional programming language originally developed for real-time telecommunications applications. Its network programming features and list management functions make it particularly well-suited for the task of managing multiple Channel Access circuits and PVmore » monitors.« less

Access and Use of New ICT Resources in Romanian Schools

ERIC Educational Resources Information Center

Onofrei, Smaranda Gabriela

2016-01-01

In the context of a digital age that marks all sectors of modern life, access and use of new technologies and the Internet by digital natives is an area with multiple speculations based on relatively little empirical research. It was noted that young people of this generation share a global common culture characterized more by their experience in…

The Role of Women's Colleges and Universities in Providing Access to Postsecondary Education

ERIC Educational Resources Information Center

Renn, Kristen A.

2017-01-01

Based on a qualitative, comparative, multiple case study of the contributions and status of 21st century women's colleges and universities, this article analyzes the topic of women's access to postsecondary education in ten nations. Despite decreasing numbers of women-only institutions in some regions (e.g., North America), the sector is growing…

Efficient traffic grooming with dynamic ONU grouping for multiple-OLT-based access network

NASA Astrophysics Data System (ADS)

Zhang, Shizong; Gu, Rentao; Ji, Yuefeng; Wang, Hongxiang

2015-12-01

Fast bandwidth growth urges large-scale high-density access scenarios, where the multiple Passive Optical Networking (PON) system clustered deployment can be adopted as an appropriate solution to fulfill the huge bandwidth demands, especially for a future 5G mobile network. However, the lack of interaction between different optical line terminals (OLTs) results in part of the bandwidth resources waste. To increase the bandwidth efficiency, as well as reduce bandwidth pressure at the edge of a network, we propose a centralized flexible PON architecture based on Time- and Wavelength-Division Multiplexing PON (TWDM PON). It can provide flexible affiliation for optical network units (ONUs) and different OLTs to support access network traffic localization. Specifically, a dynamic ONU grouping algorithm (DGA) is provided to obtain the minimal OLT outbound traffic. Simulation results show that DGA obtains an average 25.23% traffic gain increment under different OLT numbers within a small ONU number situation, and the traffic gain will increase dramatically with the increment of the ONU number. As the DGA can be deployed easily as an application running above the centralized control plane, the proposed architecture can be helpful to improve the network efficiency for future traffic-intensive access scenarios.

Study of advanced communications satellite systems based on SS-FDMA

NASA Technical Reports Server (NTRS)

Kiesling, J.

1980-01-01

A satellite communication system based on the use of a multiple, contiguous beam satellite antenna and frequency division multiple access (FDMA) is studied. Emphasis is on the evaluation of the feasibility of SS (satellite switching) FDMA technology, particularly the multiple, contiguous beam antenna, the onboard switch and channelization, and on methods to overcome the effects of severe Ka band fading caused by precipitation. This technology is evaluated and plans for technology development and evaluation are given. The application of SS-FDMA to domestic satellite communications is also evaluated. Due to the potentially low cost Earth stations, SS-FDMA is particularly attractive for thin route applications up to several hundred kilobits per second, and offers the potential for competing with terrestrial facilities at low data rates and over short routes. The onboard switch also provides added route flexibility for heavy route systems. The key beneficial SS-FDMA strategy is to simplify and thus reduce the cost of the direct access Earth station at the expense of increased satellite complexity.

Evaluation of Renal Function after Percutaneous Nephrolithotomy-Does the Number of Percutaneous Access Tracts Matter?

PubMed

Gorbachinsky, Ilya; Wood, Kyle; Colaco, Marc; Hemal, Sij; Mettu, Jayadev; Mirzazadeh, Majid; Assimos, Dean G; Gutierrez-Aćeves, Jorge

2016-07-01

Renal function following percutaneous nephrolithotomy has long been a concern to urologists, especially in the setting of multi-tract access. We determined whether the risk of renal injury after multi-tract percutaneous nephrolithotomy was greater than after a single access approach. We retrospectively reviewed the records of 307 consecutive patients treated with percutaneous nephrolithotomy from 2011 to 2012 at Wake Forest Health. Perioperative (99m)Tc-mercaptoacetyltriglycine nuclear renogram parameters along with serum creatinine values were assessed within 1 year of the procedure. Patients were stratified by single access vs multi-access (2 or more). We identified 110 cases in which renography was done before and after percutaneous nephrolithotomy. A total of 74 patients (67.3%) underwent single access percutaneous nephrolithotomy while 36 (32.7%) underwent multi-access percutaneous nephrolithotomy. Serum creatinine did not significantly differ between the 2 cohorts postoperatively (p = 0.09). There was a significant 2.28% decrease in renal function based on mercaptoacetyltriglycine nuclear renogram results after percutaneous nephrolithotomy of the affected kidney in patients with multiple accesses (p <0.01). This relationship was not observed when patients were stratified by multiple comorbidities associated with nephrolithiasis. Multi-access percutaneous nephrolithotomy is associated with a small reduction in the function of the targeted kidney compared to a single access approach. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Patient-Centered Appointment Scheduling Using Agent-Based Simulation

PubMed Central

Turkcan, Ayten; Toscos, Tammy; Doebbeling, Brad N.

2014-01-01

Enhanced access and continuity are key components of patient-centered care. Existing studies show that several interventions such as providing same day appointments, walk-in services, after-hours care, and group appointments, have been used to redesign the healthcare systems for improved access to primary care. However, an intervention focusing on a single component of care delivery (i.e. improving access to acute care) might have a negative impact other components of the system (i.e. reduced continuity of care for chronic patients). Therefore, primary care clinics should consider implementing multiple interventions tailored for their patient population needs. We collected rapid ethnography and observations to better understand clinic workflow and key constraints. We then developed an agent-based simulation model that includes all access modalities (appointments, walk-ins, and after-hours access), incorporate resources and key constraints and determine the best appointment scheduling method that improves access and continuity of care. This paper demonstrates the value of simulation models to test a variety of alternative strategies to improve access to care through scheduling. PMID:25954423

An Effective Massive Sensor Network Data Access Scheme Based on Topology Control for the Internet of Things

PubMed Central

Yi, Meng; Chen, Qingkui; Xiong, Neal N.

2016-01-01

This paper considers the distributed access and control problem of massive wireless sensor networks’ data access center for the Internet of Things, which is an extension of wireless sensor networks and an element of its topology structure. In the context of the arrival of massive service access requests at a virtual data center, this paper designs a massive sensing data access and control mechanism to improve the access efficiency of service requests and makes full use of the available resources at the data access center for the Internet of things. Firstly, this paper proposes a synergistically distributed buffer access model, which separates the information of resource and location. Secondly, the paper divides the service access requests into multiple virtual groups based on their characteristics and locations using an optimized self-organizing feature map neural network. Furthermore, this paper designs an optimal scheduling algorithm of group migration based on the combination scheme between the artificial bee colony algorithm and chaos searching theory. Finally, the experimental results demonstrate that this mechanism outperforms the existing schemes in terms of enhancing the accessibility of service requests effectively, reducing network delay, and has higher load balancing capacity and higher resource utility rate. PMID:27827878

Self-organizing feature maps for dynamic control of radio resources in CDMA microcellular networks

NASA Astrophysics Data System (ADS)

Hortos, William S.

1998-03-01

The application of artificial neural networks to the channel assignment problem for cellular code-division multiple access (CDMA) cellular networks has previously been investigated. CDMA takes advantage of voice activity and spatial isolation because its capacity is only interference limited, unlike time-division multiple access (TDMA) and frequency-division multiple access (FDMA) where capacities are bandwidth-limited. Any reduction in interference in CDMA translates linearly into increased capacity. To satisfy the high demands for new services and improved connectivity for mobile communications, microcellular and picocellular systems are being introduced. For these systems, there is a need to develop robust and efficient management procedures for the allocation of power and spectrum to maximize radio capacity. Topology-conserving mappings play an important role in the biological processing of sensory inputs. The same principles underlying Kohonen's self-organizing feature maps (SOFMs) are applied to the adaptive control of radio resources to minimize interference, hence, maximize capacity in direct-sequence (DS) CDMA networks. The approach based on SOFMs is applied to some published examples of both theoretical and empirical models of DS/CDMA microcellular networks in metropolitan areas. The results of the approach for these examples are informally compared to the performance of algorithms, based on Hopfield- Tank neural networks and on genetic algorithms, for the channel assignment problem.

Combining data from multiple sources using the CUAHSI Hydrologic Information System

NASA Astrophysics Data System (ADS)

Tarboton, D. G.; Ames, D. P.; Horsburgh, J. S.; Goodall, J. L.

2012-12-01

The Consortium of Universities for the Advancement of Hydrologic Science, Inc. (CUAHSI) has developed a Hydrologic Information System (HIS) to provide better access to data by enabling the publication, cataloging, discovery, retrieval, and analysis of hydrologic data using web services. The CUAHSI HIS is an Internet based system comprised of hydrologic databases and servers connected through web services as well as software for data publication, discovery and access. The HIS metadata catalog lists close to 100 web services registered to provide data through this system, ranging from large federal agency data sets to experimental watersheds managed by University investigators. The system's flexibility in storing and enabling public access to similarly formatted data and metadata has created a community data resource from governmental and academic data that might otherwise remain private or analyzed only in isolation. Comprehensive understanding of hydrology requires integration of this information from multiple sources. HydroDesktop is the client application developed as part of HIS to support data discovery and access through this system. HydroDesktop is founded on an open source GIS client and has a plug-in architecture that has enabled the integration of modeling and analysis capability with the functionality for data discovery and access. Model integration is possible through a plug-in built on the OpenMI standard and data visualization and analysis is supported by an R plug-in. This presentation will demonstrate HydroDesktop, showing how it provides an analysis environment within which data from multiple sources can be discovered, accessed and integrated.

A modular approach to disease registry design: successful adoption of an internet-based rare disease registry.

PubMed

Bellgard, Matthew I; Macgregor, Andrew; Janon, Fred; Harvey, Adam; O'Leary, Peter; Hunter, Adam; Dawkins, Hugh

2012-10-01

There is a need to develop Internet-based rare disease registries to support health care stakeholders to deliver improved quality patient outcomes. Such systems should be architected to enable multiple-level access by a range of user groups within a region or across regional/country borders in a secure and private way. However, this functionality is currently not available in many existing systems. A new approach to the design of an Internet-based architecture for disease registries has been developed for patients with clinical and genetic data in geographical disparate locations. The system addresses issues of multiple-level access by key stakeholders, security and privacy. The system has been successfully adopted for specific rare diseases in Australia and is open source. The results of this work demonstrate that it is feasible to design an open source Internet-based disease registry system in a scalable and customizable fashion and designed to facilitate interoperability with other systems. © 2012 Wiley Periodicals, Inc.

Color-Space-Based Visual-MIMO for V2X Communication †

PubMed Central

Kim, Jai-Eun; Kim, Ji-Won; Park, Youngil; Kim, Ki-Doo

2016-01-01

In this paper, we analyze the applicability of color-space-based, color-independent visual-MIMO for V2X. We aim to achieve a visual-MIMO scheme that can maintain the original color and brightness while performing seamless communication. We consider two scenarios of GCM based visual-MIMO for V2X. One is a multipath transmission using visual-MIMO networking and the other is multi-node V2X communication. In the scenario of multipath transmission, we analyze the channel capacity numerically and we illustrate the significance of networking information such as distance, reference color (symbol), and multiplexing-diversity mode transitions. In addition, in the V2X scenario of multiple access, we may achieve the simultaneous multiple access communication without node interferences by dividing the communication area using image processing. Finally, through numerical simulation, we show the superior SER performance of the visual-MIMO scheme compared with LED-PD communication and show the numerical result of the GCM based visual-MIMO channel capacity versus distance. PMID:27120603

Color-Space-Based Visual-MIMO for V2X Communication.

PubMed

Kim, Jai-Eun; Kim, Ji-Won; Park, Youngil; Kim, Ki-Doo

2016-04-23

In this paper, we analyze the applicability of color-space-based, color-independent visual-MIMO for V2X. We aim to achieve a visual-MIMO scheme that can maintain the original color and brightness while performing seamless communication. We consider two scenarios of GCM based visual-MIMO for V2X. One is a multipath transmission using visual-MIMO networking and the other is multi-node V2X communication. In the scenario of multipath transmission, we analyze the channel capacity numerically and we illustrate the significance of networking information such as distance, reference color (symbol), and multiplexing-diversity mode transitions. In addition, in the V2X scenario of multiple access, we may achieve the simultaneous multiple access communication without node interferences by dividing the communication area using image processing. Finally, through numerical simulation, we show the superior SER performance of the visual-MIMO scheme compared with LED-PD communication and show the numerical result of the GCM based visual-MIMO channel capacity versus distance.

Energy matters: An investigation of drama pedagogy in the science classroom

NASA Astrophysics Data System (ADS)

Alrutz, Megan

The purpose of this study is to explore and document how informal and improvisational drama techniques affect student learning in the science classroom. While implementing a drama-based science unit, I examined multiple notions of learning, including, but not limited to, traditional notions of achievement, student understanding, student participation in the science classroom, and student engagement with, and knowledge of, science content. Employing an interpretivist research methodology, as outlined by Fredrick Erickson for qualitative analysis in the classroom, I collected data through personal observations; student and teacher interviews; written, artistic and performed class work; video-recorded class work; written tests; and questionnaires. In analyzing the data, I found strong support for student engagement during drama-based science instruction. The drama-based lessons provided structures that drew students into lessons, created enthusiasm for the science curriculum, and encouraged meaningful engagement with, and connections to, the science content, including the application and synthesis of science concepts and skills. By making student contributions essential to each of the lessons, and by challenging students to justify, explain, and clarify their understandings within a dramatic scenario, the classroom facilitators created a conducive learning environment that included both support for student ideas and intellectual rigor. The integration of drama-based pedagogy most affected student access to science learning and content. Students' participation levels, as well as their interest in both science and drama, increased during this drama-based science unit. In addition, the drama-based lessons accommodated multiple learning styles and interests, improving students' access to science content and perceptions of their learning experience and abilities. Finally, while the drama-based science lessons provided multiple opportunities for solidifying understanding of the science content, the data also revealed missed opportunities for sense-making within the delivery of several drama-based science lessons. In conclusion, this study demonstrates how the integration of drama and science prepares students for seeking, accessing, and organizing information in different ways, providing multiple means for students to build knowledge and understanding for actively participating in the changing world around us.

Comprehensive security framework for the communication and storage of medical images

NASA Astrophysics Data System (ADS)

Slik, David; Montour, Mike; Altman, Tym

2003-05-01

Confidentiality, integrity verification and access control of medical imagery and associated metadata is critical for the successful deployment of integrated healthcare networks that extend beyond the department level. As medical imagery continues to become widely accessed across multiple administrative domains and geographically distributed locations, image data should be able to travel and be stored on untrusted infrastructure, including public networks and server equipment operated by external entities. Given these challenges associated with protecting large-scale distributed networks, measures must be taken to protect patient identifiable information while guarding against tampering, denial of service attacks, and providing robust audit mechanisms. The proposed framework outlines a series of security practices for the protection of medical images, incorporating Transport Layer Security (TLS), public and secret key cryptography, certificate management and a token based trusted computing base. It outlines measures that can be utilized to protect information stored within databases, online and nearline storage, and during transport over trusted and untrusted networks. In addition, it provides a framework for ensuring end-to-end integrity of image data from acquisition to viewing, and presents a potential solution to the challenges associated with access control across multiple administrative domains and institution user bases.

An Adaptive OFDMA-Based MAC Protocol for Underwater Acoustic Wireless Sensor Networks

PubMed Central

Khalil, Issa M.; Gadallah, Yasser; Hayajneh, Mohammad; Khreishah, Abdallah

2012-01-01

Underwater acoustic wireless sensor networks (UAWSNs) have many applications across various civilian and military domains. However, they suffer from the limited available bandwidth of acoustic signals and harsh underwater conditions. In this work, we present an Orthogonal Frequency Division Multiple Access (OFDMA)-based Media Access Control (MAC) protocol that is configurable to suit the operating requirements of the underwater sensor network. The protocol has three modes of operation, namely random, equal opportunity and energy-conscious modes of operation. Our MAC design approach exploits the multi-path characteristics of a fading acoustic channel to convert it into parallel independent acoustic sub-channels that undergo flat fading. Communication between node pairs within the network is done using subsets of these sub-channels, depending on the configurations of the active mode of operation. Thus, the available limited bandwidth gets fully utilized while completely avoiding interference. We derive the mathematical model for optimal power loading and subcarrier selection, which is used as basis for all modes of operation of the protocol. We also conduct many simulation experiments to evaluate and compare our protocol with other Code Division Multiple Access (CDMA)-based MAC protocols. PMID:23012517

An adaptive OFDMA-based MAC protocol for underwater acoustic wireless sensor networks.

PubMed

Khalil, Issa M; Gadallah, Yasser; Hayajneh, Mohammad; Khreishah, Abdallah

2012-01-01

Underwater acoustic wireless sensor networks (UAWSNs) have many applications across various civilian and military domains. However, they suffer from the limited available bandwidth of acoustic signals and harsh underwater conditions. In this work, we present an Orthogonal Frequency Division Multiple Access (OFDMA)-based Media Access Control (MAC) protocol that is configurable to suit the operating requirements of the underwater sensor network. The protocol has three modes of operation, namely random, equal opportunity and energy-conscious modes of operation. Our MAC design approach exploits the multi-path characteristics of a fading acoustic channel to convert it into parallel independent acoustic sub-channels that undergo flat fading. Communication between node pairs within the network is done using subsets of these sub-channels, depending on the configurations of the active mode of operation. Thus, the available limited bandwidth gets fully utilized while completely avoiding interference. We derive the mathematical model for optimal power loading and subcarrier selection, which is used as basis for all modes of operation of the protocol. We also conduct many simulation experiments to evaluate and compare our protocol with other Code Division Multiple Access (CDMA)-based MAC protocols.

A hybrid MAC protocol design for energy-efficient very-high-throughput millimeter wave, wireless sensor communication networks

NASA Astrophysics Data System (ADS)

Jian, Wei; Estevez, Claudio; Chowdhury, Arshad; Jia, Zhensheng; Wang, Jianxin; Yu, Jianguo; Chang, Gee-Kung

2010-12-01

This paper presents an energy-efficient Medium Access Control (MAC) protocol for very-high-throughput millimeter-wave (mm-wave) wireless sensor communication networks (VHT-MSCNs) based on hybrid multiple access techniques of frequency division multiplexing access (FDMA) and time division multiplexing access (TDMA). An energy-efficient Superframe for wireless sensor communication network employing directional mm-wave wireless access technologies is proposed for systems that require very high throughput, such as high definition video signals, for sensing, processing, transmitting, and actuating functions. Energy consumption modeling for each network element and comparisons among various multi-access technologies in term of power and MAC layer operations are investigated for evaluating the energy-efficient improvement of proposed MAC protocol.

NASA-Langley Web-Based Operational Real-time Cloud Retrieval Products from Geostationary Satellites

NASA Technical Reports Server (NTRS)

Palikonda, Rabindra; Minnis, Patrick; Spangenberg, Douglas A.; Khaiyer, Mandana M.; Nordeen, Michele L.; Ayers, Jeffrey K.; Nguyen, Louis; Yi, Yuhong; Chan, P. K.; Trepte, Qing Z.;

Hubless satellite communications networks

NASA Technical Reports Server (NTRS)

Robinson, Peter Alan

1994-01-01

Frequency Comb Multiple Access (FCMA) is a new combined modulation and multiple access method which will allow cheap hubless Very Small Aperture Terminal (VSAT) networks to be constructed. Theoretical results show bandwidth efficiency and power efficiency improvements over other modulation and multiple access methods. Costs of the VSAT network are reduced dramatically since a hub station is not required.

Multiple access capacity trade-offs for a Ka-band personal access satellite system

NASA Technical Reports Server (NTRS)

Dessouky, Khaled; Motamedi, Masoud

1990-01-01

System capability is critical to the economic viability of a personal satellite communication system. Ka band has significant potential to support a high capacity multiple access system because of the availability of bandwidth. System design tradeoffs are performed and multiple access schemes are compared with the design goal of achieving the highest capacity and efficiency. Conclusions regarding the efficiency of the different schemes and the achievable capacities are given.

Central venous access in children: indications, devices, and risks.

PubMed

Ares, Guillermo; Hunter, Catherine J

2017-06-01

Central venous catheters (CVCs) have a prominent role in the diagnostic and therapy of neonates and children. Herein, we describe the multiple indications for CVC use and the different devices available for central venous access. Given the prevalent use of CVCs, healthcare systems are focused on reducing complications from their use, particularly central line-associated bloodstream infections (CLABSIs). The most up-to-date information available sheds light on best practices and future areas of investigation. Large systematic reviews of randomized trials suggest that ultrasound guidance for placement of CVCs in children is safer than using blind technique, at least for internal jugular vein access. Appropriate catheter tip placement is associated with decreased complications. Furthermore, the prophylactic use of ethanol lock between cycles of parenteral nutrition administration has reduced the rates of CLABSI. A recent randomized trial in pediatric CVCs showed a benefit with antibiotic-coated CVCs. Based on the available evidence, multiple techniques for CVC placement are still valid, including the landmark technique based on practitioner experience, but ultrasound guidance has been shown to decrease complications from line placement. Adherence to CVC care protocols is essential in reducing infectious complications.

Advanced multiple access concepts in mobile satellite systems

NASA Technical Reports Server (NTRS)

Ananasso, Fulvio

1990-01-01

Some multiple access strategies for Mobile Satellite Systems (MSS) are discussed. These strategies were investigated in the context of three separate studies conducted for the International Maritime Satellite Organization (INMARSAT) and the European Space Agency (ESA). Satellite-Switched Frequency Division Multiple Access (SS-FDMA), Code Division Multiple Access (CDMA), and Frequency-Addressable Beam architectures are addressed, discussing both system and technology aspects and outlining advantages and drawbacks of either solution with associated relevant hardware issues. An attempt is made to compare the considered option from the standpoint of user terminal/space segment complexity, synchronization requirements, spectral efficiency, and interference rejection.

A novel PON-based mobile distributed cluster of antennas approach to provide impartial and broadband services to end users

NASA Astrophysics Data System (ADS)

Sana, Ajaz; Saddawi, Samir; Moghaddassi, Jalil; Hussain, Shahab; Zaidi, Syed R.

2010-01-01

In this research paper we propose a novel Passive Optical Network (PON) based Mobile Worldwide Interoperability for Microwave Access (WiMAX) access network architecture to provide high capacity and performance multimedia services to mobile WiMAX users. Passive Optical Networks (PON) networks do not require powered equipment; hence they cost lower and need less network management. WiMAX technology emerges as a viable candidate for the last mile solution. In the conventional WiMAX access networks, the base stations and Multiple Input Multiple Output (MIMO) antennas are connected by point to point lines. Ideally in theory, the Maximum WiMAX bandwidth is assumed to be 70 Mbit/s over 31 miles. In reality, WiMAX can only provide one or the other as when operating over maximum range, bit error rate increases and therefore it is required to use lower bit rate. Lowering the range allows a device to operate at higher bit rates. Our focus in this research paper is to increase both range and bit rate by utilizing distributed cluster of MIMO antennas connected to WiMAX base stations with PON based topologies. A novel quality of service (QoS) algorithm is also proposed to provide admission control and scheduling to serve classified traffic. The proposed architecture presents flexible and scalable system design with different performance requirements and complexity.

A new open-source Python-based Space Weather data access, visualization, and analysis toolkit

NASA Astrophysics Data System (ADS)

de Larquier, S.; Ribeiro, A.; Frissell, N. A.; Spaleta, J.; Kunduri, B.; Thomas, E. G.; Ruohoniemi, J.; Baker, J. B.

2013-12-01

Space weather research relies heavily on combining and comparing data from multiple observational platforms. Current frameworks exist to aggregate some of the data sources, most based on file downloads via web or ftp interfaces. Empirical models are mostly fortran based and lack interfaces with more useful scripting languages. In an effort to improve data and model access, the SuperDARN community has been developing a Python-based Space Science Data Visualization Toolkit (DaViTpy). At the center of this development was a redesign of how our data (from 30 years of SuperDARN radars) was made available. Several access solutions are now wrapped into one convenient Python interface which probes local directories, a new remote NoSQL database, and an FTP server to retrieve the requested data based on availability. Motivated by the efficiency of this interface and the inherent need for data from multiple instruments, we implemented similar modules for other space science datasets (POES, OMNI, Kp, AE...), and also included fundamental empirical models with Python interfaces to enhance data analysis (IRI, HWM, MSIS...). All these modules and more are gathered in a single convenient toolkit, which is collaboratively developed and distributed using Github and continues to grow. While still in its early stages, we expect this toolkit will facilitate multi-instrument space weather research and improve scientific productivity.

The academic, economic and societal impacts of Open Access: an evidence-based review.

PubMed

Tennant, Jonathan P; Waldner, François; Jacques, Damien C; Masuzzo, Paola; Collister, Lauren B; Hartgerink, Chris H J

2016-01-01

Ongoing debates surrounding Open Access to the scholarly literature are multifaceted and complicated by disparate and often polarised viewpoints from engaged stakeholders. At the current stage, Open Access has become such a global issue that it is critical for all involved in scholarly publishing, including policymakers, publishers, research funders, governments, learned societies, librarians, and academic communities, to be well-informed on the history, benefits, and pitfalls of Open Access. In spite of this, there is a general lack of consensus regarding the potential pros and cons of Open Access at multiple levels. This review aims to be a resource for current knowledge on the impacts of Open Access by synthesizing important research in three major areas: academic, economic and societal. While there is clearly much scope for additional research, several key trends are identified, including a broad citation advantage for researchers who publish openly, as well as additional benefits to the non-academic dissemination of their work. The economic impact of Open Access is less well-understood, although it is clear that access to the research literature is key for innovative enterprises, and a range of governmental and non-governmental services. Furthermore, Open Access has the potential to save both publishers and research funders considerable amounts of financial resources, and can provide some economic benefits to traditionally subscription-based journals. The societal impact of Open Access is strong, in particular for advancing citizen science initiatives, and leveling the playing field for researchers in developing countries. Open Access supersedes all potential alternative modes of access to the scholarly literature through enabling unrestricted re-use, and long-term stability independent of financial constraints of traditional publishers that impede knowledge sharing. However, Open Access has the potential to become unsustainable for research communities if high-cost options are allowed to continue to prevail in a widely unregulated scholarly publishing market. Open Access remains only one of the multiple challenges that the scholarly publishing system is currently facing. Yet, it provides one foundation for increasing engagement with researchers regarding ethical standards of publishing and the broader implications of 'Open Research'.

The academic, economic and societal impacts of Open Access: an evidence-based review

PubMed Central

Tennant, Jonathan P.; Waldner, François; Jacques, Damien C.; Masuzzo, Paola; Collister, Lauren B.; Hartgerink, Chris. H. J.

2016-01-01

Ongoing debates surrounding Open Access to the scholarly literature are multifaceted and complicated by disparate and often polarised viewpoints from engaged stakeholders. At the current stage, Open Access has become such a global issue that it is critical for all involved in scholarly publishing, including policymakers, publishers, research funders, governments, learned societies, librarians, and academic communities, to be well-informed on the history, benefits, and pitfalls of Open Access. In spite of this, there is a general lack of consensus regarding the potential pros and cons of Open Access at multiple levels. This review aims to be a resource for current knowledge on the impacts of Open Access by synthesizing important research in three major areas: academic, economic and societal. While there is clearly much scope for additional research, several key trends are identified, including a broad citation advantage for researchers who publish openly, as well as additional benefits to the non-academic dissemination of their work. The economic impact of Open Access is less well-understood, although it is clear that access to the research literature is key for innovative enterprises, and a range of governmental and non-governmental services. Furthermore, Open Access has the potential to save both publishers and research funders considerable amounts of financial resources, and can provide some economic benefits to traditionally subscription-based journals. The societal impact of Open Access is strong, in particular for advancing citizen science initiatives, and leveling the playing field for researchers in developing countries. Open Access supersedes all potential alternative modes of access to the scholarly literature through enabling unrestricted re-use, and long-term stability independent of financial constraints of traditional publishers that impede knowledge sharing. However, Open Access has the potential to become unsustainable for research communities if high-cost options are allowed to continue to prevail in a widely unregulated scholarly publishing market. Open Access remains only one of the multiple challenges that the scholarly publishing system is currently facing. Yet, it provides one foundation for increasing engagement with researchers regarding ethical standards of publishing and the broader implications of 'Open Research'. PMID:27158456

Using Web-Based Practice to Enhance Mathematics Learning and Achievement

ERIC Educational Resources Information Center

Nguyen, Diem M.; Kulm, Gerald

2005-01-01

This article describes 1) the special features and accessibility of an innovative web-based practice instrument (WebMA) designed with randomized short-answer, matching and multiple choice items incorporated with automatically adapted feedback for middle school students; and 2) an exploratory study that compares the effects and contributions of…

The NASA Reanalysis Ensemble Service - Advanced Capabilities for Integrated Reanalysis Access and Intercomparison

NASA Astrophysics Data System (ADS)

Tamkin, G.; Schnase, J. L.; Duffy, D.; Li, J.; Strong, S.; Thompson, J. H.

2017-12-01

NASA's efforts to advance climate analytics-as-a-service are making new capabilities available to the research community: (1) A full-featured Reanalysis Ensemble Service (RES) comprising monthly means data from multiple reanalysis data sets, accessible through an enhanced set of extraction, analytic, arithmetic, and intercomparison operations. The operations are made accessible through NASA's climate data analytics Web services and our client-side Climate Data Services Python library, CDSlib; (2) A cloud-based, high-performance Virtual Real-Time Analytics Testbed supporting a select set of climate variables. This near real-time capability enables advanced technologies like Spark and Hadoop-based MapReduce analytics over native NetCDF files; and (3) A WPS-compliant Web service interface to our climate data analytics service that will enable greater interoperability with next-generation systems such as ESGF. The Reanalysis Ensemble Service includes the following: - New API that supports full temporal, spatial, and grid-based resolution services with sample queries - A Docker-ready RES application to deploy across platforms - Extended capabilities that enable single- and multiple reanalysis area average, vertical average, re-gridding, standard deviation, and ensemble averages - Convenient, one-stop shopping for commonly used data products from multiple reanalyses including basic sub-setting and arithmetic operations (e.g., avg, sum, max, min, var, count, anomaly) - Full support for the MERRA-2 reanalysis dataset in addition to, ECMWF ERA-Interim, NCEP CFSR, JMA JRA-55 and NOAA/ESRL 20CR… - A Jupyter notebook-based distribution mechanism designed for client use cases that combines CDSlib documentation with interactive scenarios and personalized project management - Supporting analytic services for NASA GMAO Forward Processing datasets - Basic uncertainty quantification services that combine heterogeneous ensemble products with comparative observational products (e.g., reanalysis, observational, visualization) - The ability to compute and visualize multiple reanalysis for ease of inter-comparisons - Automated tools to retrieve and prepare data collections for analytic processing

Meaningful Learning from Practice: Web-Based Video in Professional Preparation Programmes in University

ERIC Educational Resources Information Center

Admiraal, Wilfried

2014-01-01

Web-based video is one of the technologies which can support meaningful learning from practice--in addition to practical benefits such as accessibility of practices, flexibility in updating information, and incorporating video into multimedia resources. A multiple case study was set up on the use of a web-based video learning environment in two…

A scheme of hidden-structure attribute-based encryption with multiple authorities

NASA Astrophysics Data System (ADS)

Ling, J.; Weng, A. X.

2018-05-01

In the most of the CP-ABE schemes with hidden access structure, both all the user attributes and the key generation are managed by only one authority. The key generation efficiency will decrease as the number of user increases, and the data will encounter security issues as the only authority is attacked. We proposed a scheme of hidden-structure attribute-based encryption with multiple authorities, which introduces multiple semi-trusted attribute authorities, avoiding the threat even though one or more authorities are attacked. We also realized user revocation by managing a revocation list. Based on DBDH assumption, we proved that our scheme is of IND-CMA security. The analysis shows that our scheme improves the key generation efficiency.

An FPGA-based DS-CDMA multiuser demodulator employing adaptive multistage parallel interference cancellation

NASA Astrophysics Data System (ADS)

Li, Xinhua; Song, Zhenyu; Zhan, Yongjie; Wu, Qiongzhi

2009-12-01

Since the system capacity is severely limited, reducing the multiple access interfere (MAI) is necessary in the multiuser direct-sequence code division multiple access (DS-CDMA) system which is used in the telecommunication terminals data-transferred link system. In this paper, we adopt an adaptive multistage parallel interference cancellation structure in the demodulator based on the least mean square (LMS) algorithm to eliminate the MAI on the basis of overviewing various of multiuser dectection schemes. Neither a training sequence nor a pilot signal is needed in the proposed scheme, and its implementation complexity can be greatly reduced by a LMS approximate algorithm. The algorithm and its FPGA implementation is then derived. Simulation results of the proposed adaptive PIC can outperform some of the existing interference cancellation methods in AWGN channels. The hardware setup of mutiuser demodulator is described, and the experimental results based on it demonstrate that the simulation results shows large performance gains over the conventional single-user demodulator.

The base rates and factors associated with reported access to firearms in psychiatric inpatients.

PubMed

Kolla, Bhanu Prakash; O'Connor, Stephen S; Lineberry, Timothy W

2011-01-01

The aim of this study was to define whether specific patient demographic groups, diagnoses or other factors are associated with psychiatric inpatients reporting firearms access. A retrospective medical records review study was conducted using information on access to firearms from electronic medical records for all patients 16 years and older admitted between July 2007 and May 2008 at the Mayo Clinic Psychiatric Hospital in Rochester, MN. Data were obtained only on patients providing authorization for record review. Data were analyzed using univariate and multivariate logistic regression analyses accounting for gender, diagnostic groups, comorbid substance use, history of suicide attempts and family history of suicide/suicide attempts. Seventy-four percent (1169/1580) of patients provided research authorization. The ratio of men to women was identical in both research and nonresearch authorization groups. There were 14.6% of inpatients who reported firearms access. In univariate analysis, men were more likely (P<.0001) to report access than women, and a history of previous suicide attempt(s) was associated with decreased access (P=.02). Multiple logistic regression analyses controlling for other factors found females and patients with history of previous suicide attempt(s) less likely to report access, while patients with a family history of suicide or suicide attempts reported increased firearms access. Diagnostic groups were not associated with access on univariate or multiple logistic regression analyses. Men and inpatients with a family history of suicide/suicide attempts were more likely to report firearms access. Clinicians should develop standardized systems of identification of firearms access and provide guidance on removal. Copyright © 2011 Elsevier Inc. All rights reserved.

Spread-spectrum multiple access using wideband noncoherent MFSK

NASA Technical Reports Server (NTRS)

Ha, Tri T.; Pratt, Timothy; Maggenti, Mark A.

1987-01-01

Two spread-spectrum multiple access systems which use wideband M-ary frequency shift keying (FSK) (MFSK) as the primary modulation are presented. A bit error rate performance analysis is presented and system throughput is calculated for sample C band and Ku band satellite systems. Sample link analyses are included to illustrate power and adjacent satellite interference considerations in practical multiple access systems.

Aeronautical audio broadcasting via satellite

NASA Technical Reports Server (NTRS)

Tzeng, Forrest F.

1993-01-01

A system design for aeronautical audio broadcasting, with C-band uplink and L-band downlink, via Inmarsat space segments is presented. Near-transparent-quality compression of 5-kHz bandwidth audio at 20.5 kbit/s is achieved based on a hybrid technique employing linear predictive modeling and transform-domain residual quantization. Concatenated Reed-Solomon/convolutional codes with quadrature phase shift keying are selected for bandwidth and power efficiency. RF bandwidth at 25 kHz per channel, and a decoded bit error rate at 10(exp -6) with E(sub b)/N(sub o) at 3.75 dB are obtained. An interleaver, scrambler, modem synchronization, and frame format were designed, and frequency-division multiple access was selected over code-division multiple access. A link budget computation based on a worst-case scenario indicates sufficient system power margins. Transponder occupancy analysis for 72 audio channels demonstrates ample remaining capacity to accommodate emerging aeronautical services.

Zadoff-Chu sequence-based hitless ranging scheme for OFDMA-PON configured 5G fronthaul uplinks

NASA Astrophysics Data System (ADS)

Reza, Ahmed Galib; Rhee, June-Koo Kevin

2017-05-01

A Zadoff-Chu (ZC) sequence-based low-complexity hitless upstream time synchronization scheme is proposed for an orthogonal frequency division multiple access passive optical network configured cloud radio access network fronthaul. The algorithm is based on gradual loading of the ZC sequences, where the phase discontinuity due to the cyclic prefix is alleviated by a frequency domain phase precoder, eliminating the requirements of guard bands to mitigate intersymbol interference and inter-carrier interference. Simulation results for uncontrolled-wavelength asynchronous transmissions from four concurrent transmitting optical network units are presented to demonstrate the effectiveness of the proposed scheme.

An approach to plan and evaluate the location of radiotherapy services and its application in the New South Wales, Australia.

PubMed

Shukla, Nagesh; Wickramasuriya, Rohan; Miller, Andrew; Perez, Pascal

2015-11-01

This paper proposes an integrated modelling approach for location planning of radiotherapy treatment services based on cancer incidence and road network-based accessibility. Previous research efforts have established travel distance/time barriers as a key factor affecting access to cancer treatment services, as well as epidemiological studies have shown that cancer incidence rates vary with population demography. Our study is built on the evidence that the travel distances to treatment centres and demographic profiles of the accessible regions greatly influence the uptake of cancer radiotherapy (RT) services. An integrated service planning approach that combines spatially-explicit cancer incidence projections, and the placement of new RT services based on road network based accessibility measures have never been attempted. This research presents a novel approach for the location planning of RT services, and demonstrates its viability by modelling cancer incidence rates for different age-sex groups in New South Wales, Australia based on observed cancer incidence trends; and estimations of the road network-based access to current NSW treatment centres. Using three indices (General Efficiency, Service Availability and Equity), we show how the best location for a new RT centre may be chosen when there are multiple competing locations. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

A Serviced-based Approach to Connect Seismological Infrastructures: Current Efforts at the IRIS DMC

NASA Astrophysics Data System (ADS)

Ahern, Tim; Trabant, Chad

2014-05-01

As part of the COOPEUS initiative to build infrastructure that connects European and US research infrastructures, IRIS has advocated for the development of Federated services based upon internationally recognized standards using web services. By deploying International Federation of Digital Seismograph Networks (FDSN) endorsed web services at multiple data centers in the US and Europe, we have shown that integration within seismological domain can be realized. By deploying identical methods to invoke the web services at multiple centers this approach can significantly ease the methods through which a scientist can access seismic data (time series, metadata, and earthquake catalogs) from distributed federated centers. IRIS has developed an IRIS federator that helps a user identify where seismic data from global seismic networks can be accessed. The web services based federator can build the appropriate URLs and return them to client software running on the scientists own computer. These URLs are then used to directly pull data from the distributed center in a very peer-based fashion. IRIS is also involved in deploying web services across horizontal domains. As part of the US National Science Foundation's (NSF) EarthCube effort, an IRIS led EarthCube Building Block's project is underway. When completed this project will aid in the discovery, access, and usability of data across multiple geoscienece domains. This presentation will summarize current IRIS efforts in building vertical integration infrastructure within seismology working closely with 5 centers in Europe and 2 centers in the US, as well as how we are taking first steps toward horizontal integration of data from 14 different domains in the US, in Europe, and around the world.

Developing a composite index of spatial accessibility across different health care sectors: A German example.

PubMed

Siegel, Martin; Koller, Daniela; Vogt, Verena; Sundmacher, Leonie

2016-02-01

The evolving lack of ambulatory care providers especially in rural areas increasingly challenges the strict separation between ambulatory and inpatient care in Germany. Some consider allowing hospitals to treat ambulatory patients to tackle potential shortages of ambulatory care in underserved areas. In this paper, we develop an integrated index of spatial accessibility covering multiple dimensions of health care. This index may contribute to the empirical evidence concerning potential risks and benefits of integrating the currently separated health care sectors. Accessibility is measured separately for each type of care based on official data at the district level. Applying an Improved Gravity Model allows us to factor in potential cross-border utilization. We combine the accessibilities for each type of care into a univariate index by adapting the concept of regional multiple deprivation measurement to allow for a limited substitutability between health care sectors. The results suggest that better health care accessibility in urban areas persists when taking a holistic view. We believe that this new index may provide an empirical basis for an inter-sectoral capacity planning. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Using Geographic Information Systems (GIS) to understand a community's primary care needs.

PubMed

Dulin, Michael F; Ludden, Thomas M; Tapp, Hazel; Blackwell, Joshua; de Hernandez, Brisa Urquieta; Smith, Heather A; Furuseth, Owen J

2010-01-01

A key element for reducing health care costs and improving community health is increased access to primary care and preventative health services. Geographic information systems (GIS) have the potential to assess patterns of health care utilization and community-level attributes to identify geographic regions most in need of primary care access. GIS, analytical hierarchy process, and multiattribute assessment and evaluation techniques were used to examine attributes describing primary care need and identify areas that would benefit from increased access to primary care services. Attributes were identified by a collaborative partnership working within a practice-based research network using tenets of community-based participatory research. Maps were created based on socioeconomic status, population density, insurance status, and emergency department and primary care safety-net utilization. Individual and composite maps identified areas in our community with the greatest need for increased access to primary care services. Applying GIS to commonly available community- and patient-level data can rapidly identify areas most in need of increased access to primary care services. We have termed this a Multiple Attribute Primary Care Targeting Strategy. This model can be used to plan health services delivery as well as to target and evaluate interventions designed to improve health care access.

Incorporating information on predicted solvent accessibility to the co-evolution-based study of protein interactions.

PubMed

Ochoa, David; García-Gutiérrez, Ponciano; Juan, David; Valencia, Alfonso; Pazos, Florencio

2013-01-27

A widespread family of methods for studying and predicting protein interactions using sequence information is based on co-evolution, quantified as similarity of phylogenetic trees. Part of the co-evolution observed between interacting proteins could be due to co-adaptation caused by inter-protein contacts. In this case, the co-evolution is expected to be more evident when evaluated on the surface of the proteins or the internal layers close to it. In this work we study the effect of incorporating information on predicted solvent accessibility to three methods for predicting protein interactions based on similarity of phylogenetic trees. We evaluate the performance of these methods in predicting different types of protein associations when trees based on positions with different characteristics of predicted accessibility are used as input. We found that predicted accessibility improves the results of two recent versions of the mirrortree methodology in predicting direct binary physical interactions, while it neither improves these methods, nor the original mirrortree method, in predicting other types of interactions. That improvement comes at no cost in terms of applicability since accessibility can be predicted for any sequence. We also found that predictions of protein-protein interactions are improved when multiple sequence alignments with a richer representation of sequences (including paralogs) are incorporated in the accessibility prediction.

A Selective Group Authentication Scheme for IoT-Based Medical Information System.

PubMed

Park, YoHan; Park, YoungHo

2017-04-01

The technology of IoT combined with medical systems is expected to support advanced medical services. However, unsolved security problems, such as misuse of medical devices, illegal access to the medical server and so on, make IoT-based medical systems not be applied widely. In addition, users have a high burden of computation to access Things for the explosive growth of IoT devices. Because medical information is critical and important, but users have a restricted computing power, IoT-based medical systems are required to provide secure and efficient authentication for users. In this paper, we propose a selective group authentication scheme using Shamir's threshold technique. The property of selectivity gives the right of choice to users to form a group which consists of things users select and access. And users can get an access authority for those Things at a time. Thus, our scheme provides an efficient user authentication for multiple Things and conditional access authority for safe IoT-based medical information system. To the best of our knowledge, our proposed scheme is the first in which selectivity is combined with group authentication in IoT environments.

GenePattern | Informatics Technology for Cancer Research (ITCR)

Cancer.gov

GenePattern is a genomic analysis platform that provides access to hundreds of tools for the analysis and visualization of multiple data types. A web-based interface provides easy access to these tools and allows the creation of multi-step analysis pipelines that enable reproducible in silico research. A new GenePattern Notebook environment allows users to combine GenePattern analyses with text, graphics, and code to create complete reproducible research narratives.

Methods and devices for determining quality of services of storage systems

DOEpatents

Seelam, Seetharami R [Yorktown Heights, NY; Teller, Patricia J [Las Cruces, NM

2012-01-17

Methods and systems for allowing access to computer storage systems. Multiple requests from multiple applications can be received and processed efficiently to allow traffic from multiple customers to access the storage system concurrently.

Ultrasonic Array for Obstacle Detection Based on CDMA with Kasami Codes

PubMed Central

Diego, Cristina; Hernández, Álvaro; Jiménez, Ana; Álvarez, Fernando J.; Sanz, Rebeca; Aparicio, Joaquín

2011-01-01

This paper raises the design of an ultrasonic array for obstacle detection based on Phased Array (PA) techniques, which steers the acoustic beam through the environment by electronics rather than mechanical means. The transmission of every element in the array has been encoded, according to Code Division for Multiple Access (CDMA), which allows multiple beams to be transmitted simultaneously. All these features together enable a parallel scanning system which does not only improve the image rate but also achieves longer inspection distances in comparison with conventional PA techniques. PMID:22247675

Development of a digital geographic data base for resource planning in a wildland environment

NASA Technical Reports Server (NTRS)

Ritter, P. R.; Benson, A. S.; Nedeff, N. E.

1981-01-01

Multiple resource planning requires the ability to access information for several parameters in a coordinated way. Attempts to do this manually, through the use of multiple transparent overlays or similar techniques can become awkward if there are more than a few parameters under consideration. One solution to this problem is to use a computer system to collect and organize the information into a data base that will make access and analysis easier, even for large numbers of parameters. The increase in the types and forms of remote sensing data and the decrease in costs for computer systems in the last decade has made this approach more popular than in the past. This paper describes the development of one such data base for the Big Basin Redwoods State Park in the Santa Cruz Mountains in California. The data base contains information for satellite spectral data, soil type, vegetation type, and hypsographic data and was developed for use in a cooperative project being conducted by personnel from the Remote Sensing Research Program and the California Department of Parks and Recreation

Mobile multiple access study

NASA Technical Reports Server (NTRS)

1977-01-01

Multiple access techniques (FDMA, CDMA, TDMA) for the mobile user and attempts to identify the current best technique are discussed. Traffic loading is considered as well as voice and data modulation and spacecraft and system design. Emphasis is placed on developing mobile terminal cost estimates for the selected design. In addition, design examples are presented for the alternative techniques of multiple access in order to compare with the selected technique.

Adaptive Code Division Multiple Access Protocol for Wireless Network-on-Chip Architectures

NASA Astrophysics Data System (ADS)

Vijayakumaran, Vineeth

Massive levels of integration following Moore's Law ushered in a paradigm shift in the way on-chip interconnections were designed. With higher and higher number of cores on the same die traditional bus based interconnections are no longer a scalable communication infrastructure. On-chip networks were proposed enabled a scalable plug-and-play mechanism for interconnecting hundreds of cores on the same chip. Wired interconnects between the cores in a traditional Network-on-Chip (NoC) system, becomes a bottleneck with increase in the number of cores thereby increasing the latency and energy to transmit signals over them. Hence, there has been many alternative emerging interconnect technologies proposed, namely, 3D, photonic and multi-band RF interconnects. Although they provide better connectivity, higher speed and higher bandwidth compared to wired interconnects; they also face challenges with heat dissipation and manufacturing difficulties. On-chip wireless interconnects is one other alternative proposed which doesn't need physical interconnection layout as data travels over the wireless medium. They are integrated into a hybrid NOC architecture consisting of both wired and wireless links, which provides higher bandwidth, lower latency, lesser area overhead and reduced energy dissipation in communication. However, as the bandwidth of the wireless channels is limited, an efficient media access control (MAC) scheme is required to enhance the utilization of the available bandwidth. This thesis proposes using a multiple access mechanism such as Code Division Multiple Access (CDMA) to enable multiple transmitter-receiver pairs to send data over the wireless channel simultaneously. It will be shown that such a hybrid wireless NoC with an efficient CDMA based MAC protocol can significantly increase the performance of the system while lowering the energy dissipation in data transfer. In this work it is shown that the wireless NoC with the proposed CDMA based MAC protocol outperformed the wired counterparts and several other wireless architectures proposed in literature in terms of bandwidth and packet energy dissipation. Significant gains were observed in packet energy dissipation and bandwidth even with scaling the system to higher number of cores. Non-uniform traffic simulations showed that the proposed CDMA-WiNoC was consistent in bandwidth across all traffic patterns. It is also shown that the CDMA based MAC scheme does not introduce additional reliability concerns in data transfer over the on-chip wireless interconnects.

The D3 Middleware Architecture

NASA Technical Reports Server (NTRS)

Walton, Joan; Filman, Robert E.; Korsmeyer, David J.; Lee, Diana D.; Mak, Ron; Patel, Tarang

2002-01-01

DARWIN is a NASA developed, Internet-based system for enabling aerospace researchers to securely and remotely access and collaborate on the analysis of aerospace vehicle design data, primarily the results of wind-tunnel testing and numeric (e.g., computational fluid-dynamics) model executions. DARWIN captures, stores and indexes data; manages derived knowledge (such as visualizations across multiple datasets); and provides an environment for designers to collaborate in the analysis of test results. DARWIN is an interesting application because it supports high-volumes of data. integrates multiple modalities of data display (e.g., images and data visualizations), and provides non-trivial access control mechanisms. DARWIN enables collaboration by allowing not only sharing visualizations of data, but also commentary about and views of data. Here we provide an overview of the architecture of D3, the third generation of DARWIN. Earlier versions of DARWIN were characterized by browser-based interfaces and a hodge-podge of server technologies: CGI scripts, applets, PERL, and so forth. But browsers proved difficult to control, and a proliferation of computational mechanisms proved inefficient and difficult to maintain. D3 substitutes a pure-Java approach for that medley: A Java client communicates (though RMI over HTTPS) with a Java-based application server. Code on the server accesses information from JDBC databases, distributed LDAP security services, and a collaborative information system. D3 is a three tier-architecture, but unlike 'E-commerce' applications, the data usage pattern suggests different strategies than traditional Enterprise Java Beans - we need to move volumes of related data together, considerable processing happens on the client, and the 'business logic' on the server-side is primarily data integration and collaboration. With D3, we are extending DARWIN to handle other data domains and to be a distributed system, where a single login allows a user transparent access to test results from multiple servers and authority domains.

A study and experiment plan for digital mobile communication via satellite

NASA Technical Reports Server (NTRS)

Jones, J. J.; Craighill, E. J.; Evans, R. G.; Vincze, A. D.; Tom, N. N.

1978-01-01

The viability of mobile communications is examined within the context of a frequency division multiple access, single channel per carrier satellite system emphasizing digital techniques to serve a large population of users. The intent is to provide the mobile users with a grade of service consistant with the requirements for remote, rural (perhaps emergency) voice communications, but which approaches toll quality speech. A traffic model is derived on which to base the determination of the required maximum number of satellite channels to provide the anticipated level of service. Various voice digitalization and digital modulation schemes are reviewed along with a general link analysis of the mobile system. Demand assignment multiple access considerations and analysis tradeoffs are presented. Finally, a completed configuration is described.

D3: A Collaborative Infrastructure for Aerospace Design

NASA Technical Reports Server (NTRS)

Walton, Joan; Filman, Robert E.; Knight, Chris; Korsmeyer, David J.; Lee, Diana D.; Clancy, Daniel (Technical Monitor)

2001-01-01

DARWIN is a NASA developed, Internet-based system for enabling aerospace researchers to securely and remotely access and collaborate on the analysis of aerospace vehicle design data, primarily the results of wind-tunnel testing and numeric (e.g., computational fluid dynamics) model executions. DARWIN captures, stores and indexes data, manages derived knowledge (such as visualizations across multiple data sets) and provides an environment for designers to collaborate in the analysis of the results of testing. DARWIN is an interesting application because it supports high volumes of data, integrates multiple modalities of data display (e.g. images and data visualizations), and provides non-trivial access control mechanisms. DARWIN enables collaboration by allowing not only sharing visualizations of data, but also commentary about and view of data.

Non-Orthogonal Multiple Access for Ubiquitous Wireless Sensor Networks.

PubMed

Anwar, Asim; Seet, Boon-Chong; Ding, Zhiguo

2018-02-08

Ubiquitous wireless sensor networks (UWSNs) have become a critical technology for enabling smart cities and other ubiquitous monitoring applications. Their deployment, however, can be seriously hampered by the spectrum available to the sheer number of sensors for communication. To support the communication needs of UWSNs without requiring more spectrum resources, the power-domain non-orthogonal multiple access (NOMA) technique originally proposed for 5th Generation (5G) cellular networks is investigated for UWSNs for the first time in this paper. However, unlike 5G networks that operate in the licensed spectrum, UWSNs mostly operate in unlicensed spectrum where sensors also experience cross-technology interferences from other devices sharing the same spectrum. In this paper, we model the interferences from various sources at the sensors using stochastic geometry framework. To evaluate the performance, we derive a theorem and present new closed form expression for the outage probability of the sensors in a downlink scenario under interference limited environment. In addition, diversity analysis for the ordered NOMA users is performed. Based on the derived outage probability, we evaluate the average link throughput and energy consumption efficiency of NOMA against conventional orthogonal multiple access (OMA) technique in UWSNs. Further, the required computational complexity for the NOMA users is presented.

Session management for web-based healthcare applications.

PubMed Central

Wei, L.; Sengupta, S.

1999-01-01

In health care systems, users may access multiple applications during one session of interaction with the system. However, users must sign on to each application individually, and it is difficult to maintain a common context among these applications. We are developing a session management system for web-based applications using LDAP directory service, which will allow single sign-on to multiple web-based applications, and maintain a common context among those applications for the user. This paper discusses the motivations for building this system, the system architecture, and the challenges of our approach, such as the session objects management for the user, and session security. PMID:10566511

An open source web interface for linking models to infrastructure system databases

NASA Astrophysics Data System (ADS)

Knox, S.; Mohamed, K.; Harou, J. J.; Rheinheimer, D. E.; Medellin-Azuara, J.; Meier, P.; Tilmant, A.; Rosenberg, D. E.

2016-12-01

Models of networked engineered resource systems such as water or energy systems are often built collaboratively with developers from different domains working at different locations. These models can be linked to large scale real world databases, and they are constantly being improved and extended. As the development and application of these models becomes more sophisticated, and the computing power required for simulations and/or optimisations increases, so has the need for online services and tools which enable the efficient development and deployment of these models. Hydra Platform is an open source, web-based data management system, which allows modellers of network-based models to remotely store network topology and associated data in a generalised manner, allowing it to serve multiple disciplines. Hydra Platform uses a web API using JSON to allow external programs (referred to as `Apps') to interact with its stored networks and perform actions such as importing data, running models, or exporting the networks to different formats. Hydra Platform supports multiple users accessing the same network and has a suite of functions for managing users and data. We present ongoing development in Hydra Platform, the Hydra Web User Interface, through which users can collaboratively manage network data and models in a web browser. The web interface allows multiple users to graphically access, edit and share their networks, run apps and view results. Through apps, which are located on the server, the web interface can give users access to external data sources and models without the need to install or configure any software. This also ensures model results can be reproduced by removing platform or version dependence. Managing data and deploying models via the web interface provides a way for multiple modellers to collaboratively manage data, deploy and monitor model runs and analyse results.

Development of the Average Likelihood Function for Code Division Multiple Access (CDMA) Using BPSK and QPSK Symbols

DTIC Science & Technology

2015-01-01

This research has the purpose to establish a foundation for new classification and estimation of CDMA signals. Keywords: DS / CDMA signals, BPSK, QPSK...DEVELOPMENT OF THE AVERAGE LIKELIHOOD FUNCTION FOR CODE DIVISION MULTIPLE ACCESS ( CDMA ) USING BPSK AND QPSK SYMBOLS JANUARY 2015...To) OCT 2013 – OCT 2014 4. TITLE AND SUBTITLE DEVELOPMENT OF THE AVERAGE LIKELIHOOD FUNCTION FOR CODE DIVISION MULTIPLE ACCESS ( CDMA ) USING BPSK

Multi-service small-cell cloud wired/wireless access network based on tunable optical frequency comb

NASA Astrophysics Data System (ADS)

Xiang, Yu; Zhou, Kun; Yang, Liu; Pan, Lei; Liao, Zhen-wan; Zhang, Qiang

2015-11-01

In this paper, we demonstrate a novel multi-service wired/wireless integrated access architecture of cloud radio access network (C-RAN) based on radio-over-fiber passive optical network (RoF-PON) system, which utilizes scalable multiple- frequency millimeter-wave (MF-MMW) generation based on tunable optical frequency comb (TOFC). In the baseband unit (BBU) pool, the generated optical comb lines are modulated into wired, RoF and WiFi/WiMAX signals, respectively. The multi-frequency RoF signals are generated by beating the optical comb line pairs in the small cell. The WiFi/WiMAX signals are demodulated after passing through the band pass filter (BPF) and band stop filter (BSF), respectively, whereas the wired signal can be received directly. The feasibility and scalability of the proposed multi-service wired/wireless integrated C-RAN are confirmed by the simulations.

Policy-based secure communication with automatic key management for industrial control and automation systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chernoguzov, Alexander; Markham, Thomas R.; Haridas, Harshal S.

A method includes generating at least one access vector associated with a specified device in an industrial process control and automation system. The specified device has one of multiple device roles. The at least one access vector is generated based on one or more communication policies defining communications between one or more pairs of devices roles in the industrial process control and automation system, where each pair of device roles includes the device role of the specified device. The method also includes providing the at least one access vector to at least one of the specified device and one ormore » more other devices in the industrial process control and automation system in order to control communications to or from the specified device.« less

Dissemination of a Multilevel Evidence-Based System of Parenting Interventions with Broad Application to Child Welfare Populations

ERIC Educational Resources Information Center

Prinz, Ron

2009-01-01

Parenting interventions are relevant to many touch points of the child welfare system. This paper describes a multilevel system of parenting interventions called "Triple P" that matches intervention intensities to families, builds on a strong scientific base, provides multiple access points for parents, and offers a destigmatized, cost-efficient…

Access to parks and physical activity: an eight country comparison.

PubMed

Schipperijn, Jasper; Cerin, Ester; Adams, Marc A; Reis, Rodrigo; Smith, Graham; Cain, Kelli; Christiansen, Lars B; van Dyck, Delfien; Gidlow, Christopher; Frank, Lawrence D; Mitáš, Josef; Pratt, Michael; Salvo, Deborah; Schofield, Grant; Sallis, James F

2017-10-01

Several systematic reviews have reported mixed associations between access to parks and physical activity, and suggest that this is due to inconsistencies in the study methods or differences across countries. An international study using consistent methods is needed to investigate the association between access to parks and physical activity. The International Physical Activity and Environment Network (IPEN) Adult Study is a multi-country cross-sectional study using a common design and consistent methods. Accelerometer, survey and Geographic Information Systems (GIS) data for 6,181 participants from 12 cities in 8 countries (Belgium, Brazil, Czech Republic, Denmark, Mexico, New Zealand, UK, USA) were used to estimate the strength and shape of associations of 11 measures of park access (1 perceived and 10 GIS-based measures) with accelerometer-based moderate-to-vigorous physical activity (MVPA) and four types of self-reported leisure-time physical activity. Associations were estimated using generalized additive mixed models. More parks within 1 km from participants' homes were associated with greater leisure-time physical activity and accelerometer-measured MVPA. Respondents who lived in the neighborhoods with the most parks did on average 24 minutes more MVPA per week than those living in the neighborhoods with the lowest number of parks. Perceived proximity to a park was positively associated with multiple leisure-time physical activity outcomes. Associations were homogeneous across all cities studied. Living in neighborhoods with many parks could contribute with up to 1/6 of the recommended weekly Having multiple parks nearby was the strongest positive correlate of PA. To increase comparability and validity of park access measures, we recommend that researchers, planners and policy makers use the number of parks within 1 km travel distance of homes as an objective indicator for park access in relation to physical activity.

Pulse patterning effect in optical pulse division multiplexing for flexible single wavelength multiple access optical network

NASA Astrophysics Data System (ADS)

Jung, Sun-Young; Kim, Chang-Hun; Han, Sang-Kook

2018-05-01

A demand for high spectral efficiency requires multiple access within a single wavelength, but the uplink signals are significantly degraded because of optical beat interference (OBI) in intensity modulation/direct detection system. An optical pulse division multiplexing (OPDM) technique was proposed that could effectively reduce the OBI via a simple method as long as near-orthogonality is satisfied, but the condition was strict, and thus, the number of multiplexing units was very limited. We propose pulse pattern enhanced OPDM (e-OPDM) to reduce the OBI and improve the flexibility in multiple access within a single wavelength. The performance of the e-OPDM and patterning effect are experimentally verified after 23-km single mode fiber transmission. By employing pulse patterning in OPDM, the tight requirement was relaxed by extending the optical delay dynamic range. This could support more number of access with reduced OBI, which could eventually enhance a multiple access function.

14 CFR Appendix A to Part 1215 - Estimated Service Rates in 1997 Dollars for TDRSS Standard Services (Based on NASA Escalation...

Code of Federal Regulations, 2010 CFR

2010-01-01

... Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION TRACKING AND DATA RELAY SATELLITE SYSTEM (TDRSS) Pt..., return telemetry, or tracking, or any combination of these, the base rate is $184.00 per minute for non-U.S. Government users. 2. Multiple Access Forward Service—Base rate is $42.00 per minute for non-U.S...

EPA's EnviroAtlas Educational Curriculum

EPA Science Inventory

U.S. EPA’s EnviroAtlas provides a collection of web-based, interactive tools for exploring ecosystem services: an Interactive Map, which provides access to 300+ maps at multiple extents for the U.S., and an Eco-Health Relationship Browser, which displays the linkages betwee...

An Adaptive Association Test for Multiple Phenotypes with GWAS Summary Statistics.

PubMed

Kim, Junghi; Bai, Yun; Pan, Wei

2015-12-01

We study the problem of testing for single marker-multiple phenotype associations based on genome-wide association study (GWAS) summary statistics without access to individual-level genotype and phenotype data. For most published GWASs, because obtaining summary data is substantially easier than accessing individual-level phenotype and genotype data, while often multiple correlated traits have been collected, the problem studied here has become increasingly important. We propose a powerful adaptive test and compare its performance with some existing tests. We illustrate its applications to analyses of a meta-analyzed GWAS dataset with three blood lipid traits and another with sex-stratified anthropometric traits, and further demonstrate its potential power gain over some existing methods through realistic simulation studies. We start from the situation with only one set of (possibly meta-analyzed) genome-wide summary statistics, then extend the method to meta-analysis of multiple sets of genome-wide summary statistics, each from one GWAS. We expect the proposed test to be useful in practice as more powerful than or complementary to existing methods. © 2015 WILEY PERIODICALS, INC.

Color coded multiple access scheme for bidirectional multiuser visible light communications in smart home technologies

NASA Astrophysics Data System (ADS)

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

2015-10-01

In optical wireless communications, multiple channel transmission is an attractive solution to enhancing capacity and system performance. A new modulation scheme called color coded multiple access (CCMA) for bidirectional multiuser visible light communications (VLC) is presented for smart home applications. The proposed scheme uses red, green and blue (RGB) light emitting diodes (LED) for downlink and phosphor based white LED (P-LED) for uplink to establish a bidirectional VLC and also employs orthogonal codes to support multiple users and devices. The downlink transmission for data user devices and smart home devices is provided using red and green colors from the RGB LEDs, respectively, while uplink transmission from both types of devices is performed using the blue color from P-LEDs. Simulations are conducted to verify the performance of the proposed scheme. It is found that the proposed bidirectional multiuser scheme is efficient in terms of data rate and performance. In addition, since the proposed scheme uses RGB signals for downlink data transmission, it provides flicker-free illumination that would lend itself to multiuser VLC system for smart home applications.

A Wideband Satcom Based Avionics Network with CDMA Uplink and TDM Downlink

NASA Technical Reports Server (NTRS)

Agrawal, D.; Johnson, B. S.; Madhow, U.; Ramchandran, K.; Chun, K. S.

2000-01-01

The purpose of this paper is to describe some key technical ideas behind our vision of a future satcom based digital communication network for avionics applications The key features of our design are as follows: (a) Packetized transmission to permit efficient use of system resources for multimedia traffic; (b) A time division multiplexed (TDM) satellite downlink whose physical layer is designed to operate the satellite link at maximum power efficiency. We show how powerful turbo codes (invented originally for linear modulation) can be used with nonlinear constant envelope modulation, thus permitting the satellite amplifier to operate in a power efficient nonlinear regime; (c) A code division multiple access (CDMA) satellite uplink, which permits efficient access to the satellite from multiple asynchronous users. Closed loop power control is difficult for bursty packetized traffic, especially given the large round trip delay to the satellite. We show how adaptive interference suppression techniques can be used to deal with the ensuing near-far problem; (d) Joint source-channel coding techniques are required both at the physical and the data transport layer to optimize the end-to-end performance. We describe a novel approach to multiple description image encoding at the data transport layer in this paper.

Multi-floor cascading ferroelectric nanostructures: multiple data writing-based multi-level non-volatile memory devices

NASA Astrophysics Data System (ADS)

Hyun, Seung; Kwon, Owoong; Lee, Bom-Yi; Seol, Daehee; Park, Beomjin; Lee, Jae Yong; Lee, Ju Hyun; Kim, Yunseok; Kim, Jin Kon

2016-01-01

Multiple data writing-based multi-level non-volatile memory has gained strong attention for next-generation memory devices to quickly accommodate an extremely large number of data bits because it is capable of storing multiple data bits in a single memory cell at once. However, all previously reported devices have failed to store a large number of data bits due to the macroscale cell size and have not allowed fast access to the stored data due to slow single data writing. Here, we introduce a novel three-dimensional multi-floor cascading polymeric ferroelectric nanostructure, successfully operating as an individual cell. In one cell, each floor has its own piezoresponse and the piezoresponse of one floor can be modulated by the bias voltage applied to the other floor, which means simultaneously written data bits in both floors can be identified. This could achieve multi-level memory through a multiple data writing process.Multiple data writing-based multi-level non-volatile memory has gained strong attention for next-generation memory devices to quickly accommodate an extremely large number of data bits because it is capable of storing multiple data bits in a single memory cell at once. However, all previously reported devices have failed to store a large number of data bits due to the macroscale cell size and have not allowed fast access to the stored data due to slow single data writing. Here, we introduce a novel three-dimensional multi-floor cascading polymeric ferroelectric nanostructure, successfully operating as an individual cell. In one cell, each floor has its own piezoresponse and the piezoresponse of one floor can be modulated by the bias voltage applied to the other floor, which means simultaneously written data bits in both floors can be identified. This could achieve multi-level memory through a multiple data writing process. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr07377d

A palliative care hotline for multiple sclerosis: A pilot feasibility study.

PubMed

Knies, Andrea K; Golla, Heidrun; Strupp, Julia; Galushko, Maren; Schipper, Sabine; Voltz, Raymond

2015-08-01

Research findings suggest that patients severely affected by multiple sclerosis benefit from palliative care. Our objectives were to (1) implement a pilot palliative care counseling hotline for severely affected multiple sclerosis patients and their caregivers in order to connect them to palliative care, and (2) evaluate its preliminary feasibility through a pilot study. The hotline was designed in cooperation with the local state association of the German Multiple Sclerosis Society and based on a review of the literature. The initial study setting for the hotline was the broader region of the cities Cologne and Bonn in Germany. The hotline was introduced through a magazine published by the German Multiple Sclerosis Society and leaflets sent to local healthcare providers. Calls were conducted using a semistructured interview guide and documented by a standardized case report form. Measures to assess feasibility were both quantitative (e.g., number of calls) and qualitative (e.g., criteria for eligibility for palliative care). During its pilot year, the hotline received 18 calls. Some 15 callers were included in the analysis, and 10 of these 15 were deemed eligible for palliative care due to such criteria as medical characteristics, care or nursing conditions, caregiver strain, and concerns regarding death and dying. Access to palliative care services could be provided for all 10 callers. Based on our pilot feasibility study, the hotline seems to be a valuable service for patients severely affected by multiple sclerosis (MS) and their caregivers in order to gain information about and access to palliative care. It will be extended on a nationwide scale through a grant of the German Multiple Sclerosis Society. Awareness of the hotline needs to be enhanced in order to attract and support a significant number of new callers.

Differential Characteristics Based Iterative Multiuser Detection for Wireless Sensor Networks

PubMed Central

Chen, Xiaoguang; Jiang, Xu; Wu, Zhilu; Zhuang, Shufeng

2017-01-01

High throughput, low latency and reliable communication has always been a hot topic for wireless sensor networks (WSNs) in various applications. Multiuser detection is widely used to suppress the bad effect of multiple access interference in WSNs. In this paper, a novel multiuser detection method based on differential characteristics is proposed to suppress multiple access interference. The proposed iterative receive method consists of three stages. Firstly, a differential characteristics function is presented based on the optimal multiuser detection decision function; then on the basis of differential characteristics, a preliminary threshold detection is utilized to find the potential wrongly received bits; after that an error bit corrector is employed to correct the wrong bits. In order to further lower the bit error ratio (BER), the differential characteristics calculation, threshold detection and error bit correction process described above are iteratively executed. Simulation results show that after only a few iterations the proposed multiuser detection method can achieve satisfactory BER performance. Besides, BER and near far resistance performance are much better than traditional suboptimal multiuser detection methods. Furthermore, the proposed iterative multiuser detection method also has a large system capacity. PMID:28212328

Using normalisation process theory to understand barriers and facilitators to implementing mindfulness-based stress reduction for people with multiple sclerosis.

PubMed

Simpson, Robert; Simpson, Sharon; Wood, Karen; Mercer, Stewart W; Mair, Frances S

2018-01-01

Objectives To study barriers and facilitators to implementation of mindfulness-based stress reduction for people with multiple sclerosis. Methods Qualitative interviews were used to explore barriers and facilitators to implementation of mindfulness-based stress reduction, including 33 people with multiple sclerosis, 6 multiple sclerosis clinicians and 2 course instructors. Normalisation process theory provided the underpinning conceptual framework. Data were analysed deductively using normalisation process theory constructs (coherence, cognitive participation, collective action and reflexive monitoring). Results Key barriers included mismatched stakeholder expectations, lack of knowledge about mindfulness-based stress reduction, high levels of comorbidity and disability and skepticism about embedding mindfulness-based stress reduction in routine multiple sclerosis care. Facilitators to implementation included introducing a pre-course orientation session; adaptations to mindfulness-based stress reduction to accommodate comorbidity and disability and participants suggested smaller, shorter classes, shortened practices, exclusion of mindful-walking and more time with peers. Post-mindfulness-based stress reduction booster sessions may be required, and objective and subjective reports of benefit would increase clinician confidence in mindfulness-based stress reduction. Discussion Multiple sclerosis patients and clinicians know little about mindfulness-based stress reduction. Mismatched expectations are a barrier to participation, as is rigid application of mindfulness-based stress reduction in the context of disability. Course adaptations in response to patient needs would facilitate uptake and utilisation. Rendering access to mindfulness-based stress reduction rapid and flexible could facilitate implementation. Embedded outcome assessment is desirable.

Use of XML and Java for collaborative petroleum reservoir modeling on the Internet

NASA Astrophysics Data System (ADS)

Victorine, John; Watney, W. Lynn; Bhattacharya, Saibal

2005-11-01

The GEMINI (Geo-Engineering Modeling through INternet Informatics) is a public-domain, web-based freeware that is made up of an integrated suite of 14 Java-based software tools to accomplish on-line, real-time geologic and engineering reservoir modeling. GEMINI facilitates distant collaborations for small company and academic clients, negotiating analyses of both single and multiple wells. The system operates on a single server and an enterprise database. External data sets must be uploaded into this database. Feedback from GEMINI users provided the impetus to develop Stand Alone Web Start Applications of GEMINI modules that reside in and operate from the user's PC. In this version, the GEMINI modules run as applets, which may reside in local user PCs, on the server, or Java Web Start. In this enhanced version, XML-based data handling procedures are used to access data from remote and local databases and save results for later access and analyses. The XML data handling process also integrates different stand-alone GEMINI modules enabling the user(s) to access multiple databases. It provides flexibility to the user to customize analytical approach, database location, and level of collaboration. An example integrated field-study using GEMINI modules and Stand Alone Web Start Applications is provided to demonstrate the versatile applicability of this freeware for cost-effective reservoir modeling.

Use of XML and Java for collaborative petroleum reservoir modeling on the Internet

USGS Publications Warehouse

Victorine, J.; Watney, W.L.; Bhattacharya, S.

2005-01-01

The GEMINI (Geo-Engineering Modeling through INternet Informatics) is a public-domain, web-based freeware that is made up of an integrated suite of 14 Java-based software tools to accomplish on-line, real-time geologic and engineering reservoir modeling. GEMINI facilitates distant collaborations for small company and academic clients, negotiating analyses of both single and multiple wells. The system operates on a single server and an enterprise database. External data sets must be uploaded into this database. Feedback from GEMINI users provided the impetus to develop Stand Alone Web Start Applications of GEMINI modules that reside in and operate from the user's PC. In this version, the GEMINI modules run as applets, which may reside in local user PCs, on the server, or Java Web Start. In this enhanced version, XML-based data handling procedures are used to access data from remote and local databases and save results for later access and analyses. The XML data handling process also integrates different stand-alone GEMINI modules enabling the user(s) to access multiple databases. It provides flexibility to the user to customize analytical approach, database location, and level of collaboration. An example integrated field-study using GEMINI modules and Stand Alone Web Start Applications is provided to demonstrate the versatile applicability of this freeware for cost-effective reservoir modeling. ?? 2005 Elsevier Ltd. All rights reserved.

A CDMA system implementation with dimming control for visible light communication

NASA Astrophysics Data System (ADS)

Chen, Danyang; Wang, Jianping; Jin, Jianli; Lu, Huimin; Feng, Lifang

2018-04-01

Visible light communication (VLC), using solid-state lightings to transmit information, has become a complement technology to wireless radio communication. As a realistic multiple access scheme for VLC system, code division multiple access (CDMA) has attracted more and more attentions in recent years. In this paper, we address and implement an improved CDMA scheme for VLC system. The simulation results reveal that the improved CDMA scheme not only supports multi-users' transmission but also maintains dimming value at about 50% and enhances the system efficiency. It can also realize the flexible dimming control by adjusting some parameters of system structure, which rarely affects the system BER performance. A real-time experimental VLC system with improved CDMA scheme is performed based on field programmable gate array (FPGA), reaching a good BER performance.

Blended Learning: An Evolving Praxis

ERIC Educational Resources Information Center

Fogal, Gary G.; Graham, Floyd H., III.; Lavigne, Anthony G.

2014-01-01

TED (Technology Entertainment Design), a collection of regularly updated talks, offers a web-based platform that is easily accessible. This platform affords language learners across multiple proficiency levels an opportunity to develop autonomy and critical thinking skills alongside their second language (L2) development. With an international…

Hybrid optical CDMA-FSO communications network under spatially correlated gamma-gamma scintillation.

PubMed

Jurado-Navas, Antonio; Raddo, Thiago R; Garrido-Balsells, José María; Borges, Ben-Hur V; Olmos, Juan José Vegas; Monroy, Idelfonso Tafur

2016-07-25

In this paper, we propose a new hybrid network solution based on asynchronous optical code-division multiple-access (OCDMA) and free-space optical (FSO) technologies for last-mile access networks, where fiber deployment is impractical. The architecture of the proposed hybrid OCDMA-FSO network is thoroughly described. The users access the network in a fully asynchronous manner by means of assigned fast frequency hopping (FFH)-based codes. In the FSO receiver, an equal gain-combining technique is employed along with intensity modulation and direct detection. New analytical formalisms for evaluating the average bit error rate (ABER) performance are also proposed. These formalisms, based on the spatially correlated gamma-gamma statistical model, are derived considering three distinct scenarios, namely, uncorrelated, totally correlated, and partially correlated channels. Numerical results show that users can successfully achieve error-free ABER levels for the three scenarios considered as long as forward error correction (FEC) algorithms are employed. Therefore, OCDMA-FSO networks can be a prospective alternative to deliver high-speed communication services to access networks with deficient fiber infrastructure.

International Cancer Genome Consortium Data Portal--a one-stop shop for cancer genomics data.

PubMed

Zhang, Junjun; Baran, Joachim; Cros, A; Guberman, Jonathan M; Haider, Syed; Hsu, Jack; Liang, Yong; Rivkin, Elena; Wang, Jianxin; Whitty, Brett; Wong-Erasmus, Marie; Yao, Long; Kasprzyk, Arek

2011-01-01

The International Cancer Genome Consortium (ICGC) is a collaborative effort to characterize genomic abnormalities in 50 different cancer types. To make this data available, the ICGC has created the ICGC Data Portal. Powered by the BioMart software, the Data Portal allows each ICGC member institution to manage and maintain its own databases locally, while seamlessly presenting all the data in a single access point for users. The Data Portal currently contains data from 24 cancer projects, including ICGC, The Cancer Genome Atlas (TCGA), Johns Hopkins University, and the Tumor Sequencing Project. It consists of 3478 genomes and 13 cancer types and subtypes. Available open access data types include simple somatic mutations, copy number alterations, structural rearrangements, gene expression, microRNAs, DNA methylation and exon junctions. Additionally, simple germline variations are available as controlled access data. The Data Portal uses a web-based graphical user interface (GUI) to offer researchers multiple ways to quickly and easily search and analyze the available data. The web interface can assist in constructing complicated queries across multiple data sets. Several application programming interfaces are also available for programmatic access. Here we describe the organization, functionality, and capabilities of the ICGC Data Portal.

Despite Increased Insurance Coverage, Nonwhite Sexual Minorities Still Experience Disparities In Access To Care.

PubMed

Hsieh, Ning; Ruther, Matt

2017-10-01

Previous studies suggest that members of sexual minority groups have poorer access to health services than heterosexuals. However, few studies have examined how sexual orientation interacts with gender and race to affect health care experience. Moreover, little is known about the role in health care disparities played by economic strains such as unemployment and poverty, which may result from prejudice and discrimination based on sexual orientation. Using data for 2013-15 from the National Health Interview Survey, we found that most members of sexual minority groups no longer have higher uninsurance rates than heterosexuals, but many continue to experience poorer access to high-quality care. Gay nonwhite men, bisexual white women, and bisexual and lesbian nonwhite women are disadvantaged in multiple aspects of access, compared to straight white men. Only some of these disparities are attributable to economic factors, which implies that noneconomic barriers to care are substantial. Our results suggest that the intersection of multiple social identities can reveal important gaps in health care experience. Making culturally sensitive services available may be key to closing the gaps. Project HOPE—The People-to-People Health Foundation, Inc.

Development of a cloud-based Bioinformatics Training Platform.

PubMed

Revote, Jerico; Watson-Haigh, Nathan S; Quenette, Steve; Bethwaite, Blair; McGrath, Annette; Shang, Catherine A

2017-05-01

The Bioinformatics Training Platform (BTP) has been developed to provide access to the computational infrastructure required to deliver sophisticated hands-on bioinformatics training courses. The BTP is a cloud-based solution that is in active use for delivering next-generation sequencing training to Australian researchers at geographically dispersed locations. The BTP was built to provide an easy, accessible, consistent and cost-effective approach to delivering workshops at host universities and organizations with a high demand for bioinformatics training but lacking the dedicated bioinformatics training suites required. To support broad uptake of the BTP, the platform has been made compatible with multiple cloud infrastructures. The BTP is an open-source and open-access resource. To date, 20 training workshops have been delivered to over 700 trainees at over 10 venues across Australia using the BTP. © The Author 2016. Published by Oxford University Press.

Development of a cloud-based Bioinformatics Training Platform

PubMed Central

Revote, Jerico; Watson-Haigh, Nathan S.; Quenette, Steve; Bethwaite, Blair; McGrath, Annette

2017-01-01

Abstract The Bioinformatics Training Platform (BTP) has been developed to provide access to the computational infrastructure required to deliver sophisticated hands-on bioinformatics training courses. The BTP is a cloud-based solution that is in active use for delivering next-generation sequencing training to Australian researchers at geographically dispersed locations. The BTP was built to provide an easy, accessible, consistent and cost-effective approach to delivering workshops at host universities and organizations with a high demand for bioinformatics training but lacking the dedicated bioinformatics training suites required. To support broad uptake of the BTP, the platform has been made compatible with multiple cloud infrastructures. The BTP is an open-source and open-access resource. To date, 20 training workshops have been delivered to over 700 trainees at over 10 venues across Australia using the BTP. PMID:27084333

Teaching science with technology: Using EPA’s EnviroAtlas in the classroom

EPA Science Inventory

Background/Question/Methods U.S. EPA’s EnviroAtlas provides a collection of web-based, interactive tools and resources for exploring ecosystem goods and services. EnviroAtlas contains two primary tools: An Interactive Map, which provides access to 300+ maps at multiple exte...

WebMeV | Informatics Technology for Cancer Research (ITCR)

Cancer.gov

Web MeV (Multiple-experiment Viewer) is a web/cloud-based tool for genomic data analysis. Web MeV is being built to meet the challenge of exploring large public genomic data set with intuitive graphical interface providing access to state-of-the-art analytical tools.

Multi-Sensor Detection with Particle Swarm Optimization for Time-Frequency Coded Cooperative WSNs Based on MC-CDMA for Underground Coal Mines

PubMed Central

Xu, Jingjing; Yang, Wei; Zhang, Linyuan; Han, Ruisong; Shao, Xiaotao

2015-01-01

In this paper, a wireless sensor network (WSN) technology adapted to underground channel conditions is developed, which has important theoretical and practical value for safety monitoring in underground coal mines. According to the characteristics that the space, time and frequency resources of underground tunnel are open, it is proposed to constitute wireless sensor nodes based on multicarrier code division multiple access (MC-CDMA) to make full use of these resources. To improve the wireless transmission performance of source sensor nodes, it is also proposed to utilize cooperative sensors with good channel conditions from the sink node to assist source sensors with poor channel conditions. Moreover, the total power of the source sensor and its cooperative sensors is allocated on the basis of their channel conditions to increase the energy efficiency of the WSN. To solve the problem that multiple access interference (MAI) arises when multiple source sensors transmit monitoring information simultaneously, a kind of multi-sensor detection (MSD) algorithm with particle swarm optimization (PSO), namely D-PSO, is proposed for the time-frequency coded cooperative MC-CDMA WSN. Simulation results show that the average bit error rate (BER) performance of the proposed WSN in an underground coal mine is improved significantly by using wireless sensor nodes based on MC-CDMA, adopting time-frequency coded cooperative transmission and D-PSO algorithm with particle swarm optimization. PMID:26343660

Prediction of protein interaction hot spots using rough set-based multiple criteria linear programming.

PubMed

Chen, Ruoying; Zhang, Zhiwang; Wu, Di; Zhang, Peng; Zhang, Xinyang; Wang, Yong; Shi, Yong

2011-01-21

Protein-protein interactions are fundamentally important in many biological processes and it is in pressing need to understand the principles of protein-protein interactions. Mutagenesis studies have found that only a small fraction of surface residues, known as hot spots, are responsible for the physical binding in protein complexes. However, revealing hot spots by mutagenesis experiments are usually time consuming and expensive. In order to complement the experimental efforts, we propose a new computational approach in this paper to predict hot spots. Our method, Rough Set-based Multiple Criteria Linear Programming (RS-MCLP), integrates rough sets theory and multiple criteria linear programming to choose dominant features and computationally predict hot spots. Our approach is benchmarked by a dataset of 904 alanine-mutated residues and the results show that our RS-MCLP method performs better than other methods, e.g., MCLP, Decision Tree, Bayes Net, and the existing HotSprint database. In addition, we reveal several biological insights based on our analysis. We find that four features (the change of accessible surface area, percentage of the change of accessible surface area, size of a residue, and atomic contacts) are critical in predicting hot spots. Furthermore, we find that three residues (Tyr, Trp, and Phe) are abundant in hot spots through analyzing the distribution of amino acids. Copyright © 2010 Elsevier Ltd. All rights reserved.

Multi-Sensor Detection with Particle Swarm Optimization for Time-Frequency Coded Cooperative WSNs Based on MC-CDMA for Underground Coal Mines.

PubMed

Xu, Jingjing; Yang, Wei; Zhang, Linyuan; Han, Ruisong; Shao, Xiaotao

2015-08-27

In this paper, a wireless sensor network (WSN) technology adapted to underground channel conditions is developed, which has important theoretical and practical value for safety monitoring in underground coal mines. According to the characteristics that the space, time and frequency resources of underground tunnel are open, it is proposed to constitute wireless sensor nodes based on multicarrier code division multiple access (MC-CDMA) to make full use of these resources. To improve the wireless transmission performance of source sensor nodes, it is also proposed to utilize cooperative sensors with good channel conditions from the sink node to assist source sensors with poor channel conditions. Moreover, the total power of the source sensor and its cooperative sensors is allocated on the basis of their channel conditions to increase the energy efficiency of the WSN. To solve the problem that multiple access interference (MAI) arises when multiple source sensors transmit monitoring information simultaneously, a kind of multi-sensor detection (MSD) algorithm with particle swarm optimization (PSO), namely D-PSO, is proposed for the time-frequency coded cooperative MC-CDMA WSN. Simulation results show that the average bit error rate (BER) performance of the proposed WSN in an underground coal mine is improved significantly by using wireless sensor nodes based on MC-CDMA, adopting time-frequency coded cooperative transmission and D-PSO algorithm with particle swarm optimization.

Performance Enhancement of MC-CDMA System through Novel Sensitive Bit Algorithm Aided Turbo Multi User Detection

PubMed Central

Kumaravel, Rasadurai; Narayanaswamy, Kumaratharan

2015-01-01

Multi carrier code division multiple access (MC-CDMA) system is a promising multi carrier modulation (MCM) technique for high data rate wireless communication over frequency selective fading channels. MC-CDMA system is a combination of code division multiple access (CDMA) and orthogonal frequency division multiplexing (OFDM). The OFDM parts reduce multipath fading and inter symbol interference (ISI) and the CDMA part increases spectrum utilization. Advantages of this technique are its robustness in case of multipath propagation and improve security with the minimize ISI. Nevertheless, due to the loss of orthogonality at the receiver in a mobile environment, the multiple access interference (MAI) appears. The MAI is one of the factors that degrade the bit error rate (BER) performance of MC-CDMA system. The multiuser detection (MUD) and turbo coding are the two dominant techniques for enhancing the performance of the MC-CDMA systems in terms of BER as a solution of overcome to MAI effects. In this paper a low complexity iterative soft sensitive bits algorithm (SBA) aided logarithmic-Maximum a-Posteriori algorithm (Log MAP) based turbo MUD is proposed. Simulation results show that the proposed method provides better BER performance with low complexity decoding, by mitigating the detrimental effects of MAI. PMID:25714917

Multi-floor cascading ferroelectric nanostructures: multiple data writing-based multi-level non-volatile memory devices.

PubMed

Hyun, Seung; Kwon, Owoong; Lee, Bom-Yi; Seol, Daehee; Park, Beomjin; Lee, Jae Yong; Lee, Ju Hyun; Kim, Yunseok; Kim, Jin Kon

2016-01-21

Multiple data writing-based multi-level non-volatile memory has gained strong attention for next-generation memory devices to quickly accommodate an extremely large number of data bits because it is capable of storing multiple data bits in a single memory cell at once. However, all previously reported devices have failed to store a large number of data bits due to the macroscale cell size and have not allowed fast access to the stored data due to slow single data writing. Here, we introduce a novel three-dimensional multi-floor cascading polymeric ferroelectric nanostructure, successfully operating as an individual cell. In one cell, each floor has its own piezoresponse and the piezoresponse of one floor can be modulated by the bias voltage applied to the other floor, which means simultaneously written data bits in both floors can be identified. This could achieve multi-level memory through a multiple data writing process.

Design of Accelerator Online Simulator Server Using Structured Data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shen, Guobao; /Brookhaven; Chu, Chungming

2012-07-06

Model based control plays an important role for a modern accelerator during beam commissioning, beam study, and even daily operation. With a realistic model, beam behaviour can be predicted and therefore effectively controlled. The approach used by most current high level application environments is to use a built-in simulation engine and feed a realistic model into that simulation engine. Instead of this traditional monolithic structure, a new approach using a client-server architecture is under development. An on-line simulator server is accessed via network accessible structured data. With this approach, a user can easily access multiple simulation codes. This paper describesmore » the design, implementation, and current status of PVData, which defines the structured data, and PVAccess, which provides network access to the structured data.« less

Zero-forcing pre-coding for MIMO WiMAX transceivers: Performance analysis and implementation issues

NASA Astrophysics Data System (ADS)

Cattoni, A. F.; Le Moullec, Y.; Sacchi, C.

Next generation wireless communication networks are expected to achieve ever increasing data rates. Multi-User Multiple-Input-Multiple-Output (MU-MIMO) is a key technique to obtain the expected performance, because such a technique combines the high capacity achievable using MIMO channel with the benefits of space division multiple access. In MU-MIMO systems, the base stations transmit signals to two or more users over the same channel, for this reason every user can experience inter-user interference. This paper provides a capacity analysis of an online, interference-based pre-coding algorithm able to mitigate the multi-user interference of the MU-MIMO systems in the context of a realistic WiMAX application scenario. Simulation results show that pre-coding can significantly increase the channel capacity. Furthermore, the paper presents several feasibility considerations for implementation of the analyzed technique in a possible FPGA-based software defined radio.

Opportunistic Access in Frequency Hopping Cognitive Radio Networks

DTIC Science & Technology

2014-03-27

thresholding MA multiple access MFSK M-ary frequency shift keying MIMO multiple-input/multiple-output OFDM orthogonal frequency-division multiplexing x...adaptive BER performance as a function of ISR with orthogonal frequency-division multiplexing ( OFDM ) interference present. . . . . . . . . . 41 4.15 Non...adaptive BER performance as a function of EB/N0 with OFDM interfer- ence present

ADS pilot program Plan

NASA Technical Reports Server (NTRS)

Clauson, J.; Heuser, J.

1981-01-01

The Applications Data Service (ADS) is a system based on an electronic data communications network which will permit scientists to share the data stored in data bases at universities and at government and private installations. It is designed to allow users to readily locate and access high quality, timely data from multiple sources. The ADS Pilot program objectives and the current plans for accomplishing those objectives are described.

Design and implement of mobile equipment management system based on QRcode

NASA Astrophysics Data System (ADS)

Yu, Runze; Duan, Xiaohui; Jiao, Bingli

2017-08-01

A mobile equipment management system based on QRcode is proposed for remote and convenient device management. Unlike conventional systems, the system here makes managers accessible to real-time information with smart phones. Compared with the conventional method, which can only be operated with specific devices, this lightweight and efficient tele management mode is conducive to the asset management in multiple scenarios.

Opto-microwave Butler matrixes based front-end for a multi-beam large direct radiating array antenna

NASA Astrophysics Data System (ADS)

Piqueras, M. A.; Mengual, T.; Navasquillo, O.; Sotom, M.; Caille, G.

2017-09-01

The evolution of broadband communication satellites shows a clear trend towards beam forming and beam-switching systems with efficient multiple access schemes with wide bandwidths, for which to be economically viable, the communication price shall be as low as possible.

Minority Engineering Programs at a Crossroads: An Empirical Multiple Case Study of Two Historically White Public Research Universities

ERIC Educational Resources Information Center

Newman, Christopher B.

2016-01-01

Purpose: Underrepresented groups have fought for equal access to higher education, which spurred the development of "minority" initiatives. However, the assault on affirmative action and race-based initiatives have led many universities to retreat toward more all-encompassing "diversity" initiatives.…

47 CFR 76.2000 - Exclusive access to multiple dwelling units generally.

Code of Federal Regulations, 2010 CFR

2010-10-01

... time share units, academic campuses and dormitories, military bases, hotels, rooming houses, prisons..., Receiver-generated, Responsibility 76.617 Isolation, Terminal 76.5 J-L Leakage measurements, Signal 76.601... noise 76.5 T Technical standards 76.605 Terminal isolation 76.5 Terminal, Subscriber 76.5 Tests...

47 CFR 76.2000 - Exclusive access to multiple dwelling units generally.

Code of Federal Regulations, 2011 CFR

2011-10-01

... time share units, academic campuses and dormitories, military bases, hotels, rooming houses, prisons..., Receiver-generated, Responsibility 76.617 Isolation, Terminal 76.5 J-L Leakage measurements, Signal 76.601... noise 76.5 T Technical standards 76.605 Terminal isolation 76.5 Terminal, Subscriber 76.5 Tests...

Multiplatform E-Learning Systems and Technologies: Mobile Devices for Ubiquitous ICT-Based Education

ERIC Educational Resources Information Center

Goh, Tiong Thye, Ed.

2010-01-01

Multiplatform e-learning systems are emerging technologies that provide integrated learning content to various accessing devices. This book addresses technical challenges, design frameworks, and development experiences of the future that integrate multiple mobile devices into a single multiplatform e-learning system. With expert international…

Event-Based Plausibility Immediately Influences On-Line Language Comprehension

ERIC Educational Resources Information Center

Matsuki, Kazunaga; Chow, Tracy; Hare, Mary; Elman, Jeffrey L.; Scheepers, Christoph; McRae, Ken

2011-01-01

In some theories of sentence comprehension, linguistically relevant lexical knowledge, such as selectional restrictions, is privileged in terms of the time-course of its access and influence. We examined whether event knowledge computed by combining multiple concepts can rapidly influence language understanding even in the absence of selectional…

Performance Analysis of Direct-Sequence Code-Division Multiple-Access Communications with Asymmetric Quadrature Phase-Shift-Keying Modulation

NASA Technical Reports Server (NTRS)

Wang, C.-W.; Stark, W.

2005-01-01

This article considers a quaternary direct-sequence code-division multiple-access (DS-CDMA) communication system with asymmetric quadrature phase-shift-keying (AQPSK) modulation for unequal error protection (UEP) capability. Both time synchronous and asynchronous cases are investigated. An expression for the probability distribution of the multiple-access interference is derived. The exact bit-error performance and the approximate performance using a Gaussian approximation and random signature sequences are evaluated by extending the techniques used for uniform quadrature phase-shift-keying (QPSK) and binary phase-shift-keying (BPSK) DS-CDMA systems. Finally, a general system model with unequal user power and the near-far problem is considered and analyzed. The results show that, for a system with UEP capability, the less protected data bits are more sensitive to the near-far effect that occurs in a multiple-access environment than are the more protected bits.

On the Performance Evaluation of a MIMO-WCDMA Transmission Architecture for Building Management Systems.

PubMed

Tsampasis, Eleftherios; Gkonis, Panagiotis K; Trakadas, Panagiotis; Zahariadis, Theodοre

2018-01-08

The goal of this study was to investigate the performance of a realistic wireless sensor nodes deployment in order to support modern building management systems (BMSs). A three-floor building orientation is taken into account, where each node is equipped with a multi-antenna system while a central base station (BS) collects and processes all received information. The BS is also equipped with multiple antennas; hence, a multiple input-multiple output (MIMO) system is formulated. Due to the multiple reflections during transmission in the inner of the building, a wideband code division multiple access (WCDMA) physical layer protocol has been considered, which has already been adopted for third-generation (3G) mobile networks. Results are presented for various MIMO orientations, where the mean transmission power per node is considered as an output metric for a specific signal-to-noise ratio (SNR) requirement and number of resolvable multipath components. In the first set of presented results, the effects of multiple access interference on overall transmission power are highlighted. As the number of mobile nodes per floor or the requested transmission rate increases, MIMO systems of a higher order should be deployed in order to maintain transmission power at adequate levels. In the second set of results, a comparison is performed among transmission in diversity combining and spatial multiplexing mode, which clearly indicate that the first case is the most appropriate solution for indoor communications.

AEROSAT Access Control Summary

DOT National Transportation Integrated Search

1976-10-01

The report consists of three basic sections. Section 2 is a discussion of the communications concepts germane to AEROSAT access control. It defines and reviews the principles of multiplexing, multiple access, demand access, and access control and rel...

Aerosat Access Control Summary

DOT National Transportation Integrated Search

1976-10-01

The report consists of three basic sections. Section 2 is a discussion of the communications concepts germane to AEROSAT access control. It defines and reviews the principles of multiplexing, multiple access, demand access, and access control and rel...

Interfaces to PeptideAtlas: a case study of standard data access systems

PubMed Central

Handcock, Jeremy; Robinson, Thomas; Deutsch, Eric W.; Boyle, John

2012-01-01

Access to public data sets is important to the scientific community as a resource to develop new experiments or validate new data. Projects such as the PeptideAtlas, Ensembl and The Cancer Genome Atlas (TCGA) offer both access to public data and a repository to share their own data. Access to these data sets is often provided through a web page form and a web service API. Access technologies based on web protocols (e.g. http) have been in use for over a decade and are widely adopted across the industry for a variety of functions (e.g. search, commercial transactions, and social media). Each architecture adapts these technologies to provide users with tools to access and share data. Both commonly used web service technologies (e.g. REST and SOAP), and custom-built solutions over HTTP are utilized in providing access to research data. Providing multiple access points ensures that the community can access the data in the simplest and most effective manner for their particular needs. This article examines three common access mechanisms for web accessible data: BioMart, caBIG, and Google Data Sources. These are illustrated by implementing each over the PeptideAtlas repository and reviewed for their suitability based on specific usages common to research. BioMart, Google Data Sources, and caBIG are each suitable for certain uses. The tradeoffs made in the development of the technology are dependent on the uses each was designed for (e.g. security versus speed). This means that an understanding of specific requirements and tradeoffs is necessary before selecting the access technology. PMID:22941959

Querying and Computing with BioCyc Databases

PubMed Central

Krummenacker, Markus; Paley, Suzanne; Mueller, Lukas; Yan, Thomas; Karp, Peter D.

2006-01-01

Summary We describe multiple methods for accessing and querying the complex and integrated cellular data in the BioCyc family of databases: access through multiple file formats, access through Application Program Interfaces (APIs) for LISP, Perl and Java, and SQL access through the BioWarehouse relational database. Availability The Pathway Tools software and 20 BioCyc DBs in Tiers 1 and 2 are freely available to academic users; fees apply to some types of commercial use. For download instructions see http://BioCyc.org/download.shtml PMID:15961440

Indexing and retrieval of multimedia objects at different levels of granularity

NASA Astrophysics Data System (ADS)

Faudemay, Pascal; Durand, Gwenael; Seyrat, Claude; Tondre, Nicolas

1998-10-01

Intelligent access to multimedia databases for `naive user' should probably be based on queries formulation by `intelligent agents'. These agents should `understand' the semantics of the contents, learn user preferences and deliver to the user a subset of the source contents, for further navigation. The goal of such systems should be to enable `zero-command' access to the contents, while keeping the freedom of choice of the user. Such systems should interpret multimedia contents in terms of multiple audiovisual objects (from video to visual or audio object), and on actions and scenarios.

Obesity and government.

PubMed

Kahan, Scott; Zvenyach, Tracy

2016-10-01

Despite much effort, obesity prevalence and disease severity continues to worsen. The purpose of this review is to describe the leading government supported food and nutrition interventions and policies to prevent and address obesity in the USA. The review also summarizes obesity interventions and policies that the government plays a role in, but further development is warranted. The government's role in obesity has largely focused on interventions and policies such as national surveillance, obesity education and awareness, grant-based food subsidy programs, zoning for food access, school-based nutrition programs, dietary guidelines, nutrition labeling, and food marketing and pricing policies. The government has played a lesser role in obesity interventions and policies that provide access to evidence-based obesity care to people affected by the disease. Given the magnitude of the obesity epidemic, the government should explore multiple evidence-based interventions and policies across prevention and clinical care.

Post-Coma Persons with Extensive Multiple Disabilities Use Microswitch Technology to Access Selected Stimulus Events or Operate a Radio Device

ERIC Educational Resources Information Center

Lancioni, Giulio E.; Singh, Nirbhay N.; O'Reilly, Mark F.; Sigafoos, Jeff; Alberti, Gloria; Oliva, Doretta; Megna, Gianfranco; Iliceto, Carla; Damiani, Sabino; Ricci, Irene; Spica, Antonella

2011-01-01

The present two studies extended research evidence on the use of microswitch technology by post-coma persons with multiple disabilities. Specifically, Study I examined whether three adults with a diagnosis of minimally conscious state and multiple disabilities could use microswitches as tools to access brief, selected stimulus events. Study II…

MAC Protocol for Ad Hoc Networks Using a Genetic Algorithm

PubMed Central

Elizarraras, Omar; Panduro, Marco; Méndez, Aldo L.

2014-01-01

The problem of obtaining the transmission rate in an ad hoc network consists in adjusting the power of each node to ensure the signal to interference ratio (SIR) and the energy required to transmit from one node to another is obtained at the same time. Therefore, an optimal transmission rate for each node in a medium access control (MAC) protocol based on CSMA-CDMA (carrier sense multiple access-code division multiple access) for ad hoc networks can be obtained using evolutionary optimization. This work proposes a genetic algorithm for the transmission rate election considering a perfect power control, and our proposition achieves improvement of 10% compared with the scheme that handles the handshaking phase to adjust the transmission rate. Furthermore, this paper proposes a genetic algorithm that solves the problem of power combining, interference, data rate, and energy ensuring the signal to interference ratio in an ad hoc network. The result of the proposed genetic algorithm has a better performance (15%) compared to the CSMA-CDMA protocol without optimizing. Therefore, we show by simulation the effectiveness of the proposed protocol in terms of the throughput. PMID:25140339

[The global and national context regarding the challenges involved in ensuring adequate access to water for human consumption].

PubMed

Augusto, Lia Giraldo da Silva; Gurgel, Idê Gomes Dantas; Câmara Neto, Henrique Fernandes; de Melo, Carlos Henrique; Costa, André Monteiro

2012-06-01

The scope of this article is to analyze the challenges involved in ensuring access to water for human consumption taking the international and national context into consideration. Based on the UN declaration that access to safe and clean drinking water is a fundamental human right, vulnerabilities are identified that can consist in restrictions to access to adequate supplies. The distribution of water and the population across the planet, pollution, inadequate policies and management lead to environmental injustice. The iniquity of access to water constitutes the contemporary water crisis. From the 1980s onwards, the transnational water market emerged for private control that occurs at three main levels: surface and underground water sources; bottled water; and public water supply services. The conflicts of the multiple uses of water resources, the market and environmental problems have contributed to rendering the health of the population and ecosystems vulnerable. Adequate public policies are essential to ensure the basic human right to access to safe and clean drinking water.

Multiple channel optical data acquisition system

DOEpatents

Fasching, G.E.; Goff, D.R.

1985-02-22

A multiple channel optical data acquisition system is provided in which a plurality of remote sensors monitoring specific process variable are interrogated by means of a single optical fiber connecting the remote station/sensors to a base station. The remote station/sensors derive all power from light transmitted through the fiber from the base station. Each station/sensor is individually accessed by means of a light modulated address code sent over the fiber. The remote station/sensors use a single light emitting diode to both send and receive light signals to communicate with the base station and provide power for the remote station. The system described can power at least 100 remote station/sensors over an optical fiber one mile in length.

Enhanced quality and quantity of retrieval of Critically Appraised Topics using the CAT Crawler.

PubMed

Dong, P; Mondry, A

2004-03-01

As healthcare moves towards the implementation of Evidence-Based Medicine (EBM), Critically Appraised Topics (CATs) become useful in helping physicians to make clinical decisions. A number of academic and healthcare organizations have set up web-based CAT libraries. The primary objective of the presented work is to provide a one-stop search and download site that allows access to multiple CAT libraries. A web-based application, namely the CAT Crawler, was developed to serve physicians with an adequate access to available appraised topics on the Internet. Important information is extracted automatically and regularly from CAT websites, and consolidated by checking the uniqueness and availability. The principle of meta-search is incorporated into the implementation of the search engine, which finds relevant topics following keyword input. The retrieved result directs the physician to the original resource page. A full-text article of a particular topic can be converted into a proper format for downloading to Personal Digital Assistant (PDA) devices. In summary, the application provides physicians with a common interface to retrieve relevant CATs on particular clinical topics from multiple resources, and thus speeds up the decision making process.

KeyWare: an open wireless distributed computing environment

NASA Astrophysics Data System (ADS)

Shpantzer, Isaac; Schoenfeld, Larry; Grindahl, Merv; Kelman, Vladimir

1995-12-01

Deployment of distributed applications in the wireless domain lack equivalent tools, methodologies, architectures, and network management that exist in LAN based applications. A wireless distributed computing environment (KeyWareTM) based on intelligent agents within a multiple client multiple server scheme was developed to resolve this problem. KeyWare renders concurrent application services to wireline and wireless client nodes encapsulated in multiple paradigms such as message delivery, database access, e-mail, and file transfer. These services and paradigms are optimized to cope with temporal and spatial radio coverage, high latency, limited throughput and transmission costs. A unified network management paradigm for both wireless and wireline facilitates seamless extensions of LAN- based management tools to include wireless nodes. A set of object oriented tools and methodologies enables direct asynchronous invocation of agent-based services supplemented by tool-sets matched to supported KeyWare paradigms. The open architecture embodiment of KeyWare enables a wide selection of client node computing platforms, operating systems, transport protocols, radio modems and infrastructures while maintaining application portability.

A web-based personal health information system for homeless youth and young adults.

PubMed

Dang, Michelle T; Whitney, Kimberley D; Virata, Maria Catrina D; Binger, Melissa M; Miller, Elizabeth

2012-01-01

Runaway and homeless youth face multiple challenges to their health and experience inadequate access to health care services. This article describes a web-based personal health information system (PHIS) called Healthshack that was specifically designed to improve health care access and health outcomes for runaway and homeless youth at a community-based agency that served homeless youth and young adults up to age 24. The program was developed in partnership with homeless youth and piloted by public health nurses. Preliminary findings from the program indicate that a PHIS is acceptable to runaway and homeless youth and feasible to incorporate into the flow of a youth agency. Thus, a PHIS may be an innovative model of service delivery for other marginalized populations. © 2011 Wiley Periodicals, Inc.

A System for Distributing Real-Time Customized (NEXRAD-Radar) Geosciences Data

NASA Astrophysics Data System (ADS)

Singh, Satpreet; McWhirter, Jeff; Krajewski, Witold; Kruger, Anton; Goska, Radoslaw; Seo, Bongchul; Domaszczynski, Piotr; Weber, Jeff

2010-05-01

Hydrometeorologists and hydrologists can benefit from (weather) radar derived rain products, including rain rates and accumulations. The Hydro-NEXRAD system (HNX1) has been in operation since 2006 at IIHR-Hydroscience and Engineering at The University of Iowa. It provides rapid and user-friendly access to such user-customized products, generated using archived Weather Surveillance Doppler Radar (WSR-88D) data from the NEXRAD weather radar network in the United States. HNX1 allows researchers to deal directly with radar-derived rain products, without the burden of the details of radar data collection, quality control, processing, and format conversion. A number of hydrologic applications can benefit from a continuous real-time feed of customized radar-derived rain products. We are currently developing such a system, Hydro-NEXRAD 2 (HNX2). HNX2 collects real-time, unprocessed data from multiple NEXRAD radars as they become available, processes them through a user-configurable pipeline of data-processing modules, and then publishes processed products at regular intervals. Modules in the data processing pipeline encapsulate algorithms such as non-meteorological echo detection, range correction, radar-reflectivity-rain rate (Z-R) conversion, advection correction, merging products from multiple radars, and grid transformations. HNX2's implementation presents significant challenges, including quality-control, error-handling, time-synchronization of data from multiple asynchronous sources, generation of multiple-radar metadata products, distribution of products to a user base with diverse needs and constraints, and scalability. For content management and distribution, HNX2 uses RAMADDA (Repository for Archiving, Managing and Accessing Diverse Data), developed by the UCAR/Unidata Program Center in the Unites States. RAMADDA allows HNX2 to publish products through automation and gives users multiple access methods to the published products, including simple web-browser based access, and OpenDAP access. The latter allows a user to set up automation at his/her end, and fetch new data from HNX2 at regular intervals. HNX2 uses a two-dimensional metadata structure called a mosaic for managing metadata of the rain products. Currently, HNX2 is in pre-production state and is serving near real-time rain-rate map data-products for individual radars and merged data-products from seven radars covering the state of Iowa in the United States. These products then drive a rainfall-runoff model called CUENCAS, which is used as part of the Iowa Flood Center (housed at The University of Iowa) real-time flood forecasting system. We are currently developing a generalized scalable framework that will run on inexpensive hardware and will provide products for basins anywhere in the continental United States.

SARA-Coffee web server, a tool for the computation of RNA sequence and structure multiple alignments

PubMed Central

Di Tommaso, Paolo; Bussotti, Giovanni; Kemena, Carsten; Capriotti, Emidio; Chatzou, Maria; Prieto, Pablo; Notredame, Cedric

2014-01-01

This article introduces the SARA-Coffee web server; a service allowing the online computation of 3D structure based multiple RNA sequence alignments. The server makes it possible to combine sequences with and without known 3D structures. Given a set of sequences SARA-Coffee outputs a multiple sequence alignment along with a reliability index for every sequence, column and aligned residue. SARA-Coffee combines SARA, a pairwise structural RNA aligner with the R-Coffee multiple RNA aligner in a way that has been shown to improve alignment accuracy over most sequence aligners when enough structural data is available. The server can be accessed from http://tcoffee.crg.cat/apps/tcoffee/do:saracoffee. PMID:24972831

Searchable attribute-based encryption scheme with attribute revocation in cloud storage.

PubMed

Wang, Shangping; Zhao, Duqiao; Zhang, Yaling

2017-01-01

Attribute based encryption (ABE) is a good way to achieve flexible and secure access control to data, and attribute revocation is the extension of the attribute-based encryption, and the keyword search is an indispensable part for cloud storage. The combination of both has an important application in the cloud storage. In this paper, we construct a searchable attribute-based encryption scheme with attribute revocation in cloud storage, the keyword search in our scheme is attribute based with access control, when the search succeeds, the cloud server returns the corresponding cipher text to user and the user can decrypt the cipher text definitely. Besides, our scheme supports multiple keywords search, which makes the scheme more practical. Under the assumption of decisional bilinear Diffie-Hellman exponent (q-BDHE) and decisional Diffie-Hellman (DDH) in the selective security model, we prove that our scheme is secure.

A development framework for artificial intelligence based distributed operations support systems

NASA Technical Reports Server (NTRS)

Adler, Richard M.; Cottman, Bruce H.

1990-01-01

Advanced automation is required to reduce costly human operations support requirements for complex space-based and ground control systems. Existing knowledge based technologies have been used successfully to automate individual operations tasks. Considerably less progress has been made in integrating and coordinating multiple operations applications for unified intelligent support systems. To fill this gap, SOCIAL, a tool set for developing Distributed Artificial Intelligence (DAI) systems is being constructed. SOCIAL consists of three primary language based components defining: models of interprocess communication across heterogeneous platforms; models for interprocess coordination, concurrency control, and fault management; and for accessing heterogeneous information resources. DAI applications subsystems, either new or existing, will access these distributed services non-intrusively, via high-level message-based protocols. SOCIAL will reduce the complexity of distributed communications, control, and integration, enabling developers to concentrate on the design and functionality of the target DAI system itself.

Interplay between morphology and frequency in lexical access: The case of the base frequency effect

PubMed Central

Vannest, Jennifer; Newport, Elissa L.; Newman, Aaron J.; Bavelier, Daphne

2011-01-01

A major issue in lexical processing concerns storage and access of lexical items. Here we make use of the base frequency effect to examine this. Specifically, reaction time to morphologically complex words (words made up of base and suffix, e.g., agree+able) typically reflects frequency of the base element (i.e., total frequency of all words in which agree appears) rather than surface word frequency (i.e., frequency of agreeable itself). We term these complex words decomposable. However, a class of words termed whole-word do not show such sensitivity to base frequency (e.g., serenity). Using an event-related MRI design, we exploited the fact that processing low-frequency words increases BOLD activity relative to high frequency ones, and examined effects of base frequency on brain activity for decomposable and whole-word items. Morphologically complex words, half high and half low base frequency, were compared to matched high and low frequency simple monomorphemic words using a lexical decision task. Morphologically complex words increased activation in left inferior frontal and left superior temporal cortices versus simple words. The only area to mirror the behavioral distinction between decomposable and whole-word types was the thalamus. Surprisingly, most frequency-sensitive areas failed to show base frequency effects. This variety of responses to frequency and word type across brain areas supports an integrative view of multiple variables during lexical access, rather than a dichotomy between memory-based access and on-line computation. Lexical access appears best captured as interplay of several neural processes with different sensitivities to various linguistic factors including frequency and morphological complexity. PMID:21167136

Gambling involvement and increased risk of gambling problems.

PubMed

Phillips, James G; Ogeil, Rowan; Chow, Yang-Wai; Blaszczynski, Alex

2013-12-01

The opportunity to gamble has undergone rapid expansion with technology allowing for access to gambling products 24 h a day. This increased online availability challenges governments' abilities to restrict access to gambling. Indeed, the ready access to multiple forms of gambling may potentially contribute to impaired control over urges for problem gamblers. The present study considered whether problem gamblers manifested a tendency to engage in multiple forms of gambling and identified forms of gambling which were more strongly related to problem gambling. In reanalyses of two surveys (Sample 1, N = 464, Sample 2, N = 1141), significant relationships accounting for between 11.3 and 13.5% of the variance were found between the numbers of forms of gambling accessed and degree of problem. Participation in online poker, playing cards and sports wagering were linked to problem gambling. Access to multiple forms of gambling may pose difficulties for the tracking and control of gambling.

Genetic diversity and population structure analysis in Perilla frutescens from Northern areas of China based on simple sequence repeats.

PubMed

Ma, S J; Sa, K J; Hong, T K; Lee, J K

2017-09-21

In this study, 21 simple sequence repeat (SSR) markers were used to evaluate the genetic diversity and population structure among 77 Perilla accessions from high-latitude and middle-latitude areas of China. Ninety-five alleles were identified with an average of 4.52 alleles per locus. The average polymorphic information content (PIC) and genetic diversity values were 0.346 and 0.372, respectively. The level of genetic diversity and PIC value for cultivated accessions of Perilla frutescens var. frutescens from middle-latitude areas were higher than accessions from high-latitude areas. Based on the dendrogram of unweighted pair group method with arithmetic mean (UPGMA), all accessions were classified into four major groups with a genetic similarity of 46%. All accessions of the cultivated var. frutescens were discriminated from the cultivated P. frutescens var. crispa. Furthermore, most accessions of the cultivated var. frutescens collected in high-latitude and middle-latitude areas were distinguished depending on their geographical location. However, the geographical locations of several accessions of the cultivated var. frutescens have no relation with their positions in the UPGMA dendrogram and population structure. This result implies that the diffusion of accessions of the cultivated Perilla crop in the northern areas of China might be through multiple routes. On the population structure analysis, 77 Perilla accessions were divided into Group I, Group II, and an admixed group based on a membership probability threshold of 0.8. Finally, the findings in this study can provide useful theoretical knowledge for further study on the population structure and genetic diversity of Perilla and benefit for Perilla crop breeding and germplasm conservation.

Quantum internet using code division multiple access

PubMed Central

Zhang, Jing; Liu, Yu-xi; Özdemir, Şahin Kaya; Wu, Re-Bing; Gao, Feifei; Wang, Xiang-Bin; Yang, Lan; Nori, Franco

2013-01-01

A crucial open problem inS large-scale quantum networks is how to efficiently transmit quantum data among many pairs of users via a common data-transmission medium. We propose a solution by developing a quantum code division multiple access (q-CDMA) approach in which quantum information is chaotically encoded to spread its spectral content, and then decoded via chaos synchronization to separate different sender-receiver pairs. In comparison to other existing approaches, such as frequency division multiple access (FDMA), the proposed q-CDMA can greatly increase the information rates per channel used, especially for very noisy quantum channels. PMID:23860488

Design analysis tracking and data relay satellite simulation system

NASA Technical Reports Server (NTRS)

1974-01-01

The design and development of the equipment necessary to simulate the S-band multiple access link between user spacecraft, the Tracking and Data Relay Satellite, and a ground control terminal are discussed. The core of the S-band multiple access concept is the use of an Adaptive Ground Implemented Phased Array. The array contains thirty channels and provides the multiplexing and demultiplexing equipment required to demonstrate the ground implemented beam forming feature. The system provided will make it possible to demonstrate the performance of a desired user and ten interfering sources attempting to pass data through the multiple access system.

Web-based Hyper Suprime-Cam Data Providing System

NASA Astrophysics Data System (ADS)

Koike, M.; Furusawa, H.; Takata, T.; Price, P.; Okura, Y.; Yamada, Y.; Yamanoi, H.; Yasuda, N.; Bickerton, S.; Katayama, N.; Mineo, S.; Lupton, R.; Bosch, J.; Loomis, C.

2014-05-01

We describe a web-based user interface to retrieve Hyper Suprime-Cam data products, including images and. Users can access data directly from a graphical user interface or by writing a database SQL query. The system provides raw images, reduced images and stacked images (from multiple individual exposures), with previews available. Catalog queries can be executed in preview or queue mode, allowing for both exploratory and comprehensive investigations.

QCL-based nonlinear sensing of independent targets dynamics.

PubMed

Mezzapesa, F P; Columbo, L L; Dabbicco, M; Brambilla, M; Scamarcio, G

2014-03-10

We demonstrate a common-path interferometer to measure the independent displacement of multiple targets through nonlinear frequency mixing in a quantum-cascade laser (QCL). The sensing system exploits the unique stability of QCLs under strong optical feedback to access the intrinsic nonlinearity of the active medium. The experimental results using an external dual cavity are in excellent agreement with the numerical simulations based on the Lang-Kobayashi equations.

Effect of Personality on the Use and Perceived Utility of Web-Based Health Resources

ERIC Educational Resources Information Center

Hruska, Natalie

2012-01-01

Studies document numerous threats to human health exacerbated by multiple factors, including inadequate access to health-related information. The Internet has developed as one resource to provide health information; however, there remains a significant gap in understanding how personality differences influence the use and perceived utility of the…

Language Accessibility in the Classroom: How UDL Can Promote Success for Linguistically Diverse Learners

ERIC Educational Resources Information Center

Rice Doran, Patricia

2015-01-01

This article provides an overview of the Universal Design for Learning (UDL) framework, which is based on brain-structure research and which incorporates multiple means of instruction, action and expression, and engagement. The article describes the relevance of this framework to linguistically diverse and culturally and linguistically diverse…

Applying Universal Design for Learning in Online Courses: Pedagogical and Practical Considerations

ERIC Educational Resources Information Center

Dell, Cindy Ann; Dell, Thomas F.; Blackwell, Terry L.

2015-01-01

Inclusion of the universal design for learning (UDL) model as a guiding set of principles for online curriculum development in higher education is discussed. Fundamentally, UDL provides the student with multiple means of accessing the course based on three overarching principles: presentation; action and expression; and engagement and interaction.…

Identification and Classification of Orthogonal Frequency Division Multiple Access (OFDMA) Signals Used in Next Generation Wireless Systems

DTIC Science & Technology

2012-03-01

advanced antenna systems AMC adaptive modulation and coding AWGN additive white Gaussian noise BPSK binary phase shift keying BS base station BTC ...QAM-16, and QAM-64, and coding types include convolutional coding (CC), convolutional turbo coding (CTC), block turbo coding ( BTC ), zero-terminating

Clinical Views: Object-Oriented Views for Clinical Databases

PubMed Central

Portoni, Luisa; Combi, Carlo; Pinciroli, Francesco

1998-01-01

We present here a prototype of a clinical information system for the archiving and the management of multimedia and temporally-oriented clinical data related to PTCA patients. The system is based on an object-oriented DBMS and supports multiple views and view schemas on patients' data. Remote data access is supported too.

Moving beyond the Name: Defining Corporate Entities to Support Provenance-Based Access

ERIC Educational Resources Information Center

Light, Michelle

2007-01-01

The second edition of the "International Standard Archival Authority Records for Corporate Bodies, Persons, and Families (ISAAR(CPF)2)" focuses on describing entities as they exist in reality, rather than on establishing authorized terms. This change allows authority records to include multiple authorized terms representing an entity as it changed…

bioWeb3D: an online webGL 3D data visualisation tool.

PubMed

Pettit, Jean-Baptiste; Marioni, John C

2013-06-07

Data visualization is critical for interpreting biological data. However, in practice it can prove to be a bottleneck for non trained researchers; this is especially true for three dimensional (3D) data representation. Whilst existing software can provide all necessary functionalities to represent and manipulate biological 3D datasets, very few are easily accessible (browser based), cross platform and accessible to non-expert users. An online HTML5/WebGL based 3D visualisation tool has been developed to allow biologists to quickly and easily view interactive and customizable three dimensional representations of their data along with multiple layers of information. Using the WebGL library Three.js written in Javascript, bioWeb3D allows the simultaneous visualisation of multiple large datasets inputted via a simple JSON, XML or CSV file, which can be read and analysed locally thanks to HTML5 capabilities. Using basic 3D representation techniques in a technologically innovative context, we provide a program that is not intended to compete with professional 3D representation software, but that instead enables a quick and intuitive representation of reasonably large 3D datasets.

Frequency Hopping, Multiple Frequency-Shift Keying, Coding, and Optimal Partial-Band Jamming.

DTIC Science & Technology

1982-08-01

receivers appropriate for these two strategies. Each receiver is noncoherent (a coherent receiver is generally impractical) and implements hard...Advances in Coding and Modulation for Noncoherent Channels Affected by Fading, Partial Band, and Multiple- . Access Interference, in A. J. Viterbi...Modulation for Noncoherent Channels Affected by Fading, Partial Band, and Multiple-Access interference, in A. J. Viterbi, ed., Advances in Coumunication

Clandestine Transmissions and Operations of Embedded Software on Cellular Mobile Devices

DTIC Science & Technology

2011-09-01

Register EMS Enhanced Message Service FDMA Frequency Division Multiple Access GMT Greenwich Mean Time GMSC Gateway Mobile Switching Center...Message Switching Center SMS-IWMSC SMS-Interworking Mobile-Service Switching Center TCH Traffic Channels TDMA Time Division Multiple Access TP...assume the user will not attempt to re-program the device. Finally, we assume that the owner and user do not have root access and cannot disable any

An Architecture for Enabling Migration of Tactical Networks to Future Flexible Ad Hoc WBWF

DTIC Science & Technology

2010-09-01

Requirements Several multiple access schemes TDMA OFDMA SC-OFDMA, FH- CDMA , DS - CDMA , hybrid access schemes, transitions between them Dynamic...parameters algorithms depend on the multiple access scheme If DS - CDMA : handling of macro-diversity (linked to cooperative routing) TDMA and/of OFDMA...Transport format Ciphering @MAC/RLC level : SCM Physical layer (PHY) : signal processing (mod, FEC, etc) CDMA : macro-diversity CDMA , OFDMA

Conceptual framework of the Controlling Asthma in American Cities Project.

PubMed

Herman, Elizabeth Jane

2011-02-01

The Controlling Asthma in American Cities Project (CAACP) was designed to improve the control of asthma in inner-city populations of children with a disparate burden of symptoms and adverse outcomes. As with many chronic diseases, asthma is the manifestation of multiple biologic, environmental, and social determinants. In addition to appropriate medical management, individuals with asthma must have logistical, financial, and cultural access to environments that allow avoidance of asthma triggers and encourage good asthma management practices. In recognition of this complexity, the CAACP required the seven project sites to coordinate and synchronize multiple interventions (education, healthcare access, medical management, trigger reduction) at multiple levels (individual, home, school, community, and policy) through the collaboration of relevant groups, institutions, and individuals. This paper describes the "program theory" of the CAACP project-the assumptions about how the project worked, how the components were linked, and what outcomes were anticipated. It relates the subsequent papers in the supplement to the program theory and describes how the papers can inform and guide other community-based interventions, and advance the translation of scientific knowledge to effective interventions in communities of need.

Full Duplex, Spread Spectrum Radio System

NASA Technical Reports Server (NTRS)

Harvey, Bruce A.

2000-01-01

The goal of this project was to support the development of a full duplex, spread spectrum voice communications system. The assembly and testing of a prototype system consisting of a Harris PRISM spread spectrum radio, a TMS320C54x signal processing development board and a Zilog Z80180 microprocessor was underway at the start of this project. The efforts under this project were the development of multiple access schemes, analysis of full duplex voice feedback delays, and the development and analysis of forward error correction (FEC) algorithms. The multiple access analysis involved the selection between code division multiple access (CDMA), frequency division multiple access (FDMA) and time division multiple access (TDMA). Full duplex voice feedback analysis involved the analysis of packet size and delays associated with full loop voice feedback for confirmation of radio system performance. FEC analysis included studies of the performance under the expected burst error scenario with the relatively short packet lengths, and analysis of implementation in the TMS320C54x digital signal processor. When the capabilities and the limitations of the components used were considered, the multiple access scheme chosen was a combination TDMA/FDMA scheme that will provide up to eight users on each of three separate frequencies. Packets to and from each user will consist of 16 samples at a rate of 8,000 samples per second for a total of 2 ms of voice information. The resulting voice feedback delay will therefore be 4 - 6 ms. The most practical FEC algorithm for implementation was a convolutional code with a Viterbi decoder. Interleaving of the bits of each packet will be required to offset the effects of burst errors.

System and method for integrating and accessing multiple data sources within a data warehouse architecture

DOEpatents

Musick, Charles R [Castro Valley, CA; Critchlow, Terence [Livermore, CA; Ganesh, Madhaven [San Jose, CA; Slezak, Tom [Livermore, CA; Fidelis, Krzysztof [Brentwood, CA

2006-12-19

A system and method is disclosed for integrating and accessing multiple data sources within a data warehouse architecture. The metadata formed by the present method provide a way to declaratively present domain specific knowledge, obtained by analyzing data sources, in a consistent and useable way. Four types of information are represented by the metadata: abstract concepts, databases, transformations and mappings. A mediator generator automatically generates data management computer code based on the metadata. The resulting code defines a translation library and a mediator class. The translation library provides a data representation for domain specific knowledge represented in a data warehouse, including "get" and "set" methods for attributes that call transformation methods and derive a value of an attribute if it is missing. The mediator class defines methods that take "distinguished" high-level objects as input and traverse their data structures and enter information into the data warehouse.

Simulation realization of 2-D wavelength/time system utilizing MDW code for OCDMA system

NASA Astrophysics Data System (ADS)

Azura, M. S. A.; Rashidi, C. B. M.; Aljunid, S. A.; Endut, R.; Ali, N.

2017-11-01

This paper presents a realization of Wavelength/Time (W/T) Two-Dimensional Modified Double Weight (2-D MDW) code for Optical Code Division Multiple Access (OCDMA) system based on Spectral Amplitude Coding (SAC) approach. The MDW code has the capability to suppress Phase-Induce Intensity Noise (PIIN) and minimizing the Multiple Access Interference (MAI) noises. At the permissible BER 10-9, the 2-D MDW (APD) had shown minimum effective received power (Psr) = -71 dBm that can be obtained at the receiver side as compared to 2-D MDW (PIN) only received -61 dBm. The results show that 2-D MDW (APD) has better performance in achieving same BER with longer optical fiber length and with less received power (Psr). Also, the BER from the result shows that MDW code has the capability to suppress PIIN ad MAI.

Providing end-to-end QoS for multimedia applications in 3G wireless networks

NASA Astrophysics Data System (ADS)

Guo, Katherine; Rangarajan, Samapth; Siddiqui, M. A.; Paul, Sanjoy

2003-11-01

As the usage of wireless packet data services increases, wireless carriers today are faced with the challenge of offering multimedia applications with QoS requirements within current 3G data networks. End-to-end QoS requires support at the application, network, link and medium access control (MAC) layers. We discuss existing CDMA2000 network architecture and show its shortcomings that prevent supporting multiple classes of traffic at the Radio Access Network (RAN). We then propose changes in RAN within the standards framework that enable support for multiple traffic classes. In addition, we discuss how Session Initiation Protocol (SIP) can be augmented with QoS signaling for supporting end-to-end QoS. We also review state of the art scheduling algorithms at the base station and provide possible extensions to these algorithms to support different classes of traffic as well as different classes of users.

Database Development for Electrical, Electronic, and Electromechanical (EEE) Parts for the International Space Station Alpha

NASA Technical Reports Server (NTRS)

Wassil-Grimm, Andrew D.

1997-01-01

More effective electronic communication processes are needed to transfer contractor and international partner data into NASA and prime contractor baseline database systems. It is estimated that the International Space Station Alpha (ISSA) parts database will contain up to one million parts each of which may require database capabilities for approximately one thousand bytes of data for each part. The resulting gigabyte database must provide easy access to users who will be preparing multiple analyses and reports in order to verify as-designed, as-built, launch, on-orbit, and return configurations for up to 45 missions associated with the construction of the ISSA. Additionally, Internet access to this data base is strongly indicated to allow multiple user access from clients located in many foreign countries. This summer's project involved familiarization and evaluation of the ISSA Electrical, Electronic, and Electromechanical (EEE) Parts data and the process of electronically managing these data. Particular attention was devoted to improving the interfaces among the many elements of the ISSA information system and its global customers and suppliers. Additionally, prototype queries were developed to facilitate the identification of data changes in the data base, verifications that the designs used only approved parts, and certifications that the flight hardware containing EEE parts was ready for flight. This project also resulted in specific recommendations to NASA for further development in the area of EEE parts database development and usage.

Providing Access and Visualization to Global Cloud Properties from GEO Satellites

NASA Astrophysics Data System (ADS)

Chee, T.; Nguyen, L.; Minnis, P.; Spangenberg, D.; Palikonda, R.; Ayers, J. K.

2015-12-01

Providing public access to cloud macro and microphysical properties is a key concern for the NASA Langley Research Center Cloud and Radiation Group. This work describes a tool and method that allows end users to easily browse and access cloud information that is otherwise difficult to acquire and manipulate. The core of the tool is an application-programming interface that is made available to the public. One goal of the tool is to provide a demonstration to end users so that they can use the dynamically generated imagery as an input into their own work flows for both image generation and cloud product requisition. This project builds upon NASA Langley Cloud and Radiation Group's experience with making real-time and historical satellite cloud product imagery accessible and easily searchable. As we see the increasing use of virtual supply chains that provide additional value at each link there is value in making satellite derived cloud product information available through a simple access method as well as allowing users to browse and view that imagery as they need rather than in a manner most convenient for the data provider. Using the Open Geospatial Consortium's Web Processing Service as our access method, we describe a system that uses a hybrid local and cloud based parallel processing system that can return both satellite imagery and cloud product imagery as well as the binary data used to generate them in multiple formats. The images and cloud products are sourced from multiple satellites and also "merged" datasets created by temporally and spatially matching satellite sensors. Finally, the tool and API allow users to access information that spans the time ranges that our group has information available. In the case of satellite imagery, the temporal range can span the entire lifetime of the sensor.

Iowa Flood Information System: Towards Integrated Data Management, Analysis and Visualization

NASA Astrophysics Data System (ADS)

Demir, I.; Krajewski, W. F.; Goska, R.; Mantilla, R.; Weber, L. J.; Young, N.

2012-04-01

The Iowa Flood Information System (IFIS) is a web-based platform developed by the Iowa Flood Center (IFC) to provide access to flood inundation maps, real-time flood conditions, flood forecasts both short-term and seasonal, flood-related data, information and interactive visualizations for communities in Iowa. The key element of the system's architecture is the notion of community. Locations of the communities, those near streams and rivers, define basin boundaries. The IFIS provides community-centric watershed and river characteristics, weather (rainfall) conditions, and streamflow data and visualization tools. Interactive interfaces allow access to inundation maps for different stage and return period values, and flooding scenarios with contributions from multiple rivers. Real-time and historical data of water levels, gauge heights, and rainfall conditions are available in the IFIS by streaming data from automated IFC bridge sensors, USGS stream gauges, NEXRAD radars, and NWS forecasts. Simple 2D and 3D interactive visualizations in the IFIS make the data more understandable to general public. Users are able to filter data sources for their communities and selected rivers. The data and information on IFIS is also accessible through web services and mobile applications. The IFIS is optimized for various browsers and screen sizes to provide access through multiple platforms including tablets and mobile devices. The IFIS includes a rainfall-runoff forecast model to provide a five-day flood risk estimate for around 500 communities in Iowa. Multiple view modes in the IFIS accommodate different user types from general public to researchers and decision makers by providing different level of tools and details. River view mode allows users to visualize data from multiple IFC bridge sensors and USGS stream gauges to follow flooding condition along a river. The IFIS will help communities make better-informed decisions on the occurrence of floods, and will alert communities in advance to help minimize damage of floods. This presentation provides an overview and live demonstration of the tools and interfaces in the IFIS developed to date to provide a platform for one-stop access to flood related data, visualizations, flood conditions, and forecast.

Iowa Flood Information System

NASA Astrophysics Data System (ADS)

Demir, I.; Krajewski, W. F.; Goska, R.; Mantilla, R.; Weber, L. J.; Young, N.

2011-12-01

The Iowa Flood Information System (IFIS) is a web-based platform developed by the Iowa Flood Center (IFC) to provide access to flood inundation maps, real-time flood conditions, flood forecasts both short-term and seasonal, flood-related data, information and interactive visualizations for communities in Iowa. The key element of the system's architecture is the notion of community. Locations of the communities, those near streams and rivers, define basin boundaries. The IFIS provides community-centric watershed and river characteristics, weather (rainfall) conditions, and streamflow data and visualization tools. Interactive interfaces allow access to inundation maps for different stage and return period values, and flooding scenarios with contributions from multiple rivers. Real-time and historical data of water levels, gauge heights, and rainfall conditions are available in the IFIS by streaming data from automated IFC bridge sensors, USGS stream gauges, NEXRAD radars, and NWS forecasts. Simple 2D and 3D interactive visualizations in the IFIS make the data more understandable to general public. Users are able to filter data sources for their communities and selected rivers. The data and information on IFIS is also accessible through web services and mobile applications. The IFIS is optimized for various browsers and screen sizes to provide access through multiple platforms including tablets and mobile devices. The IFIS includes a rainfall-runoff forecast model to provide a five-day flood risk estimate for around 500 communities in Iowa. Multiple view modes in the IFIS accommodate different user types from general public to researchers and decision makers by providing different level of tools and details. River view mode allows users to visualize data from multiple IFC bridge sensors and USGS stream gauges to follow flooding condition along a river. The IFIS will help communities make better-informed decisions on the occurrence of floods, and will alert communities in advance to help minimize damage of floods. This presentation provides an overview of the tools and interfaces in the IFIS developed to date to provide a platform for one-stop access to flood related data, visualizations, flood conditions, and forecast.

Flood Risk Management in Iowa through an Integrated Flood Information System

NASA Astrophysics Data System (ADS)

Demir, Ibrahim; Krajewski, Witold

2013-04-01

The Iowa Flood Information System (IFIS) is a web-based platform developed by the Iowa Flood Center (IFC) to provide access to flood inundation maps, real-time flood conditions, flood forecasts both short-term and seasonal, flood-related data, information and interactive visualizations for communities in Iowa. The key element of the system's architecture is the notion of community. Locations of the communities, those near streams and rivers, define basin boundaries. The IFIS provides community-centric watershed and river characteristics, weather (rainfall) conditions, and streamflow data and visualization tools. Interactive interfaces allow access to inundation maps for different stage and return period values, and flooding scenarios with contributions from multiple rivers. Real-time and historical data of water levels, gauge heights, and rainfall conditions are available in the IFIS by streaming data from automated IFC bridge sensors, USGS stream gauges, NEXRAD radars, and NWS forecasts. Simple 2D and 3D interactive visualizations in the IFIS make the data more understandable to general public. Users are able to filter data sources for their communities and selected rivers. The data and information on IFIS is also accessible through web services and mobile applications. The IFIS is optimized for various browsers and screen sizes to provide access through multiple platforms including tablets and mobile devices. The IFIS includes a rainfall-runoff forecast model to provide a five-day flood risk estimate for around 1100 communities in Iowa. Multiple view modes in the IFIS accommodate different user types from general public to researchers and decision makers by providing different level of tools and details. River view mode allows users to visualize data from multiple IFC bridge sensors and USGS stream gauges to follow flooding condition along a river. The IFIS will help communities make better-informed decisions on the occurrence of floods, and will alert communities in advance to help minimize damage of floods. This presentation provides an overview and live demonstration of the tools and interfaces in the IFIS developed to date to provide a platform for one-stop access to flood related data, visualizations, flood conditions, and forecast.

Capturing the Sun: A Roadmap for Navigating Data-Access Challenges and Auto-Populating Solar Home Sales Listings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stukel, Laura; Hoen, Ben; Adomatis, Sandra

Capturing the Sun: A Roadmap for Navigating Data-Access Challenges and Auto-Populating Solar Home Sales Listings supports a vision of solar photovoltaic (PV) advocates and real estate advocates evolving together to make information about solar homes more accessible to home buyers and sellers and to simplify the process when these homes are resold. The Roadmap is based on a concept in the real estate industry known as automatic population of fields. Auto-population (also called auto-pop in the industry) is the technology that allows data aggregated by an outside industry to be matched automatically with home sale listings in a multiple listingmore » service (MLS).« less

Adaptive receiver structures for asynchronous CDMA systems

NASA Astrophysics Data System (ADS)

Rapajic, Predrag B.; Vucetic, Branka S.

1994-05-01

Adaptive linear and decision feedback receiver structures for coherent demodulation in asynchronous code division multiple access (CDMA) systems are considered. It is assumed that the adaptive receiver has no knowledge of the signature waveforms and timing of other users. The receiver is trained by a known training sequence prior to data transmission and continuously adjusted by an adaptive algorithm during data transmission. The proposed linear receiver is as simple as a standard single-user detector receiver consisting of a matched filter with constant coefficients, but achieves essential advantages with respect to timing recovery, multiple access interference elimination, near/far effect, narrowband and frequency-selective fading interference suppression, and user privacy. An adaptive centralized decision feedback receiver has the same advantages of the linear receiver but, in addition, achieves a further improvement in multiple access interference cancellation at the expense of higher complexity. The proposed receiver structures are tested by simulation over a channel with multipath propagation, multiple access interference, narrowband interference, and additive white Gaussian noise.

A comparison of Frequency Domain Multiple Access (FDMA) and Time Domain Multiple Access (TDMA) approaches to satellite service for low data rate Earth stations

NASA Technical Reports Server (NTRS)

Stevens, G.

1983-01-01

A technological and economic assessment is made of providing low data rate service to small earth stations by satellite at Ka-band. Various Frequency Domain Multiple Access (FDMA) and Time Domain Multiple Access (TDMA) scenarios are examined and compared on the basis of cost to the end user. Very small stations (1 to 2 meters in diameter) are found not to be viable alternatives to available terrestrial services. However, medium size (3 to 5 meters) earth stations appear to be very competitive if a minimum throughput of about 1.5 Mbs is maintained. This constrains the use of such terminals to large users and shared use by smaller users. No advantage was found to the use of FDMA. TDMA had a slight advantage from a total system viewpoint and a very significant advantage in the space segment (about 1/3 the required payload weight for an equivalent capacity).

I/O performance evaluation of a Linux-based network-attached storage device

NASA Astrophysics Data System (ADS)

Sun, Zhaoyan; Dong, Yonggui; Wu, Jinglian; Jia, Huibo; Feng, Guanping

2002-09-01

In a Local Area Network (LAN), clients are permitted to access the files on high-density optical disks via a network server. But the quality of read service offered by the conventional server is not satisfied because of the multiple functions on the server and the overmuch caller. This paper develops a Linux-based Network-Attached Storage (NAS) server. The Operation System (OS), composed of an optimized kernel and a miniaturized file system, is stored in a flash memory. After initialization, the NAS device is connected into the LAN. The administrator and users could configure the access the server through the web page respectively. In order to enhance the quality of access, the management of buffer cache in file system is optimized. Some benchmark programs are peformed to evaluate the I/O performance of the NAS device. Since data recorded in optical disks are usually for reading accesses, our attention is focused on the reading throughput of the device. The experimental results indicate that the I/O performance of our NAS device is excellent.

Barriers to patient portal access among veterans receiving home-based primary care: a qualitative study.

PubMed

Mishuris, Rebecca G; Stewart, Max; Fix, Gemmae M; Marcello, Thomas; McInnes, D Keith; Hogan, Timothy P; Boardman, Judith B; Simon, Steven R

2015-12-01

Electronic, or web-based, patient portals can improve patient satisfaction, engagement and health outcomes and are becoming more prevalent with the advent of meaningful use incentives. However, adoption rates are low, particularly among vulnerable patient populations, such as those patients who are home-bound with multiple comorbidities. Little is known about how these patients view patient portals or their barriers to using them. To identify barriers to and facilitators of using My HealtheVet (MHV), the United States Department of Veterans Affairs (VA) patient portal, among Veterans using home-based primary care services. Qualitative study using in-depth semi-structured interviews. We conducted a content analysis informed by grounded theory. Fourteen Veterans receiving home-based primary care, surrogates of two of these Veterans, and three home-based primary care (HBPC) staff members. We identified five themes related to the use of MHV: limited knowledge; satisfaction with current HBPC care; limited computer and Internet access; desire to learn more about MHV and its potential use; and value of surrogates acting as intermediaries between Veterans and MHV. Despite their limited knowledge of MHV and computer access, home-bound Veterans are interested in accessing MHV and using it as an additional point of care. Surrogates are also potential users of MHV on behalf of these Veterans and may have different barriers to and benefits from use. © 2014 John Wiley & Sons Ltd.

The Correlation Between Poverty and Access to Essential Surgical Care in Ghana: A Geospatial Analysis

PubMed Central

Stewart, Barclay T.; Gyedu, Adam; Boakye, Godfred; Lewis, Daniel; Hoogerboord, Marius; Mock, Charles

2017-01-01

Background Surgical disease burden falls disproportionately on individuals in low- and middle-income countries. These populations are also the least likely to have access to surgical care. Understanding the barriers to access in these populations is therefore necessary to meet the global surgical need. Methods Using geospatial methods, this study explores the district-level variation of two access barriers in Ghana: poverty and spatial access to care. National survey data were used to estimate the average total household expenditure (THE) in each district. Estimates of the spatial access to essential surgical care were generated from a cost-distance model based on a recent surgical capacity assessment. Correlations were analyzed using regression and displayed cartographically. Results Both THE and spatial access to surgical care were found to have statistically significant regional variation in Ghana (p < 0.001). An inverse relationship was identified between THE and spatial access to essential surgical care (β −5.15 USD, p < 0.001). Poverty and poor spatial access to surgical care were found to co-localize in the northwest of the country. Conclusions Multiple barriers to accessing surgical care can coexist within populations. A careful understanding of all access barriers is necessary to identify and target strategies to address unmet surgical need within a given population. PMID:27766400

A Low Cost Micro-Computer Based Local Area Network for Medical Office and Medical Center Automation

PubMed Central

Epstein, Mel H.; Epstein, Lynn H.; Emerson, Ron G.

1984-01-01

A Low Cost Micro-computer based Local Area Network for medical office automation is described which makes use of an array of multiple and different personal computers interconnected by a local area network. Each computer on the network functions as fully potent workstations for data entry and report generation. The network allows each workstation complete access to the entire database. Additionally, designated computers may serve as access ports for remote terminals. Through “Gateways” the network may serve as a front end for a large mainframe, or may interface with another network. The system provides for the medical office environment the expandability and flexibility of a multi-terminal mainframe system at a far lower cost without sacrifice of performance.

Real-Time Data Filtering and Compression in Wide Area Simulation Networks

DTIC Science & Technology

1992-10-02

Area Simulation Networks Achieving the real-time linkage among multiple , geographically-distant, local area networks that support distributed...November 1989, pp. 52-61. [IEEE85] IEEE/ANSI Standard 8802/3 "Carrier sense multiple access with collision detection (CSMA/CD) access method and...decoding/encoding of multiple bits. The hardware is programmable, easily adaptable and yields a high compression rate. A prototype 2-micron VLSI chip

Evaluation of CDMA system capacity for mobile satellite system applications

NASA Technical Reports Server (NTRS)

Smith, Partrick O.; Geraniotis, Evaggelos A.

1988-01-01

A specific Direct-Sequence/Pseudo-Noise (DS/PN) Code-Division Multiple-Access (CDMA) mobile satellite system (MSAT) architecture is discussed. The performance of this system is evaluated in terms of the maximum number of active MSAT subscribers that can be supported at a given uncoded bit-error probability. The evaluation decouples the analysis of the multiple-access capability (i.e., the number of instantaneous user signals) from the analysis of the multiple-access mutliplier effect allowed by the use of CDMA with burst-modem operation. We combine the results of these two analyses and present numerical results for scenarios of interest to the mobile satellite system community.

Asynchronous, Decentralized DS-CDMA Using Feedback-Controlled Spreading Sequences for Time-Dispersive Channels

NASA Astrophysics Data System (ADS)

Miyatake, Teruhiko; Chiba, Kazuki; Hamamura, Masanori; Tachikawa, Shin'ichi

We propose a novel asynchronous direct-sequence codedivision multiple access (DS-CDMA) using feedback-controlled spreading sequences (FCSSs) (FCSS/DS-CDMA). At the receiver of FCSS/DS-CDMA, the code-orthogonalizing filter (COF) produces a spreading sequence, and the receiver returns the spreading sequence to the transmitter. Then the transmitter uses the spreading sequence as its updated version. The performance of FCSS/DS-CDMA is evaluated over time-dispersive channels. The results indicate that FCSS/DS-CDMA greatly suppresses both the intersymbol interference (ISI) and multiple access interference (MAI) over time-invariant channels. FCSS/DS-CDMA is applicable to the decentralized multiple access.

On the Performance Evaluation of a MIMO–WCDMA Transmission Architecture for Building Management Systems

PubMed Central

Tsampasis, Eleftherios; Gkonis, Panagiotis K.; Trakadas, Panagiotis; Zahariadis, Theodοre

2018-01-01

The goal of this study was to investigate the performance of a realistic wireless sensor nodes deployment in order to support modern building management systems (BMSs). A three-floor building orientation is taken into account, where each node is equipped with a multi-antenna system while a central base station (BS) collects and processes all received information. The BS is also equipped with multiple antennas; hence, a multiple input–multiple output (MIMO) system is formulated. Due to the multiple reflections during transmission in the inner of the building, a wideband code division multiple access (WCDMA) physical layer protocol has been considered, which has already been adopted for third-generation (3G) mobile networks. Results are presented for various MIMO orientations, where the mean transmission power per node is considered as an output metric for a specific signal-to-noise ratio (SNR) requirement and number of resolvable multipath components. In the first set of presented results, the effects of multiple access interference on overall transmission power are highlighted. As the number of mobile nodes per floor or the requested transmission rate increases, MIMO systems of a higher order should be deployed in order to maintain transmission power at adequate levels. In the second set of results, a comparison is performed among transmission in diversity combining and spatial multiplexing mode, which clearly indicate that the first case is the most appropriate solution for indoor communications. PMID:29316720

Access point selection game with mobile users using correlated equilibrium.

PubMed

Sohn, Insoo

2015-01-01

One of the most important issues in wireless local area network (WLAN) systems with multiple access points (APs) is the AP selection problem. Game theory is a mathematical tool used to analyze the interactions in multiplayer systems and has been applied to various problems in wireless networks. Correlated equilibrium (CE) is one of the powerful game theory solution concepts, which is more general than the Nash equilibrium for analyzing the interactions in multiplayer mixed strategy games. A game-theoretic formulation of the AP selection problem with mobile users is presented using a novel scheme based on a regret-based learning procedure. Through convergence analysis, we show that the joint actions based on the proposed algorithm achieve CE. Simulation results illustrate that the proposed algorithm is effective in a realistic WLAN environment with user mobility and achieves maximum system throughput based on the game-theoretic formulation.

Access Point Selection Game with Mobile Users Using Correlated Equilibrium

PubMed Central

Sohn, Insoo

2015-01-01

One of the most important issues in wireless local area network (WLAN) systems with multiple access points (APs) is the AP selection problem. Game theory is a mathematical tool used to analyze the interactions in multiplayer systems and has been applied to various problems in wireless networks. Correlated equilibrium (CE) is one of the powerful game theory solution concepts, which is more general than the Nash equilibrium for analyzing the interactions in multiplayer mixed strategy games. A game-theoretic formulation of the AP selection problem with mobile users is presented using a novel scheme based on a regret-based learning procedure. Through convergence analysis, we show that the joint actions based on the proposed algorithm achieve CE. Simulation results illustrate that the proposed algorithm is effective in a realistic WLAN environment with user mobility and achieves maximum system throughput based on the game-theoretic formulation. PMID:25785726

A Brief Survey of Media Access Control, Data Link Layer, and Protocol Technologies for Lunar Surface Communications

NASA Technical Reports Server (NTRS)

Wallett, Thomas M.

2009-01-01

This paper surveys and describes some of the existing media access control and data link layer technologies for possible application in lunar surface communications and the advanced wideband Direct Sequence Code Division Multiple Access (DSCDMA) conceptual systems utilizing phased-array technology that will evolve in the next decade. Time Domain Multiple Access (TDMA) and Code Division Multiple Access (CDMA) are standard Media Access Control (MAC) techniques that can be incorporated into lunar surface communications architectures. Another novel hybrid technique that is recently being developed for use with smart antenna technology combines the advantages of CDMA with those of TDMA. The relatively new and sundry wireless LAN data link layer protocols that are continually under development offer distinct advantages for lunar surface applications over the legacy protocols which are not wireless. Also several communication transport and routing protocols can be chosen with characteristics commensurate with smart antenna systems to provide spacecraft communications for links exhibiting high capacity on the surface of the Moon. The proper choices depend on the specific communication requirements.

A satellite-based personal communication system for the 21st century

NASA Technical Reports Server (NTRS)

Sue, Miles K.; Dessouky, Khaled; Levitt, Barry; Rafferty, William

1990-01-01

Interest in personal communications (PCOMM) has been stimulated by recent developments in satellite and terrestrial mobile communications. A personal access satellite system (PASS) concept was developed at the Jet Propulsion Laboratory (JPL) which has many attractive user features, including service diversity and a handheld terminal. Significant technical challenges addressed in formulating the PASS space and ground segments are discussed. PASS system concept and basic design features, high risk enabling technologies, an optimized multiple access scheme, alternative antenna coverage concepts, the use of non-geostationary orbits, user terminal radiation constraints, and user terminal frequency reference are covered.

Location Based Application Availability

NASA Astrophysics Data System (ADS)

Naeem Akram, Raja; Markantonakis, Konstantinos; Mayes, Keith

Smart cards are being integrated into a diverse range of industries: ranging from banking, telecom, transport, home/office access control to health and E-passport. Traditionally, cardholders are required to carry a smart card for each application. However, recent developments in the Near Field Communication (NFC) have renewed the interest in multiple applications for different services on a single device. This paper builds onto the NFC initiative and avoids the smart card ownership issues that hinder the adoption of such devices. The proposal integrates the Global Positioning System with the NFC in mobile phones to provide a ubiquitously and flexible service access model.

GLAD: a system for developing and deploying large-scale bioinformatics grid.

PubMed

Teo, Yong-Meng; Wang, Xianbing; Ng, Yew-Kwong

2005-03-01

Grid computing is used to solve large-scale bioinformatics problems with gigabytes database by distributing the computation across multiple platforms. Until now in developing bioinformatics grid applications, it is extremely tedious to design and implement the component algorithms and parallelization techniques for different classes of problems, and to access remotely located sequence database files of varying formats across the grid. In this study, we propose a grid programming toolkit, GLAD (Grid Life sciences Applications Developer), which facilitates the development and deployment of bioinformatics applications on a grid. GLAD has been developed using ALiCE (Adaptive scaLable Internet-based Computing Engine), a Java-based grid middleware, which exploits the task-based parallelism. Two bioinformatics benchmark applications, such as distributed sequence comparison and distributed progressive multiple sequence alignment, have been developed using GLAD.

Priority and Negotiation Based Dynamic Spectrum Allocation Scheme for Multiple Radio Access Network Operators

NASA Astrophysics Data System (ADS)

Kim, Hoon; Hyon, Taein; Lee, Yeonwoo

Most of previous works have presented the dynamic spectrum allocation (DSA) gain achieved by utilizing the time or regional variations in traffic demand between multi-network operators (NOs). In this paper, we introduce the functionalities required for the entities related with the spectrum sharing and allocation and propose a spectrum allocation algorithm while considering the long-term priority between NOs, the priority between multiple class services, and the urgent bandwidth request. To take into account the priorities among the NOs and the priorities of multiple class services, a spectrum sharing metric (SSM) is proposed, while a negotiation procedure is proposed to treat the urgent bandwidth request.

BCM Search Launcher--an integrated interface to molecular biology data base search and analysis services available on the World Wide Web.

PubMed

Smith, R F; Wiese, B A; Wojzynski, M K; Davison, D B; Worley, K C

1996-05-01

The BCM Search Launcher is an integrated set of World Wide Web (WWW) pages that organize molecular biology-related search and analysis services available on the WWW by function, and provide a single point of entry for related searches. The Protein Sequence Search Page, for example, provides a single sequence entry form for submitting sequences to WWW servers that offer remote access to a variety of different protein sequence search tools, including BLAST, FASTA, Smith-Waterman, BEAUTY, PROSITE, and BLOCKS searches. Other Launch pages provide access to (1) nucleic acid sequence searches, (2) multiple and pair-wise sequence alignments, (3) gene feature searches, (4) protein secondary structure prediction, and (5) miscellaneous sequence utilities (e.g., six-frame translation). The BCM Search Launcher also provides a mechanism to extend the utility of other WWW services by adding supplementary hypertext links to results returned by remote servers. For example, links to the NCBI's Entrez data base and to the Sequence Retrieval System (SRS) are added to search results returned by the NCBI's WWW BLAST server. These links provide easy access to auxiliary information, such as Medline abstracts, that can be extremely helpful when analyzing BLAST data base hits. For new or infrequent users of sequence data base search tools, we have preset the default search parameters to provide the most informative first-pass sequence analysis possible. We have also developed a batch client interface for Unix and Macintosh computers that allows multiple input sequences to be searched automatically as a background task, with the results returned as individual HTML documents directly to the user's system. The BCM Search Launcher and batch client are available on the WWW at URL http:@gc.bcm.tmc.edu:8088/search-launcher.html.

A primer on intraosseous access: History, clinical considerations, and current devices.

PubMed

Burgert, James M

2016-01-01

Intraosseous (IO) access is a method recommended by the American Heart Association and the European Resuscitation Council to administer resuscitative drugs and fluids when intravenous (IV) access cannot be rapidly or easily obtained. Many clinicians have limited knowledge or experience with the IO route. The purpose of this review was to provide the reader with a succinct review of the history, clinical considerations, and devices associated with IO access. Narrative review. University-based academic research cell. Not applicable. Not applicable. IO access is a lifesaving bridge to definitive vascular access that may be considered when an IV cannot be rapidly attained and the patient's outcome may be negatively affected without prompt circulatory access. The IO route has few contraindications for use and a low rate of serious complications. Multiple manual and powered devices that may be placed in several anatomic sites are commercially available. All clinicians who provide acute care or respond to cardiovascular emergencies should obtain training and maintain proficiency in placing and using IO devices as the IO route is recommended by the major resuscitation organizations as the preferred route of infusion when rapid, reliable IV access is unavailable.

Non-unique key B-Tree implementation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ries, D.R.

1980-12-23

The B-Trees are an indexed method to allow fast retrieval and order preserving updates to a FRAMIS relation based on a designated set of keys in the relation. A B-Tree access method is being implemented to provide indexed and sequential (in index order) access to FRAMIS relations. The implementation modifies the basic B-Tree structure to correctly allow multiple key values and still maintain the balanced page fill property of B-Trees. The data structures of the B-Tree are presented first, including the FRAMIS solution to the duplicate key value problem. Then the access level routines and utilities are presented. These routinesmore » include the original B-Tree creation; searching the B-Tree; and inserting, deleting, and replacing tuples on the B-Tree. In conclusion, the uses of the B-Tree access structures at the semantic level to enhance the FRAMIS performance are discussed. 10 figures.« less

Leveraging the U.S. Criminal Justice System to Access Women for HIV Interventions.

PubMed

Meyer, Jaimie P; Muthulingam, Dharushana; El-Bassel, Nabila; Altice, Frederick L

2017-12-01

The criminal justice (CJ) system can be leveraged to access women for HIV prevention and treatment programs. Research is lacking on effective implementation strategies tailored to the specific needs of CJ-involved women. We conducted a scoping review of published studies in English from the United States that described HIV interventions, involved women or girls, and used the CJ system as an access point for sampling or intervention delivery. We identified 350 studies and synthesized data from 42 unique interventions, based in closed (n = 26), community (n = 7), or multiple/other CJ settings (n = 9). A minority of reviewed programs incorporated women-specific content or conducted gender-stratified analyses. CJ systems are comprised of diverse access points, each with unique strengths and challenges for implementing HIV treatment and prevention programs for women. Further study is warranted to develop women-specific and trauma-informed content and evaluate program effectiveness.

Channel MAC Protocol for Opportunistic Communication in Ad Hoc Wireless Networks

NASA Astrophysics Data System (ADS)

Ashraf, Manzur; Jayasuriya, Aruna; Perreau, Sylvie

2008-12-01

Despite significant research effort, the performance of distributed medium access control methods has failed to meet theoretical expectations. This paper proposes a protocol named "Channel MAC" performing a fully distributed medium access control based on opportunistic communication principles. In this protocol, nodes access the channel when the channel quality increases beyond a threshold, while neighbouring nodes are deemed to be silent. Once a node starts transmitting, it will keep transmitting until the channel becomes "bad." We derive an analytical throughput limit for Channel MAC in a shared multiple access environment. Furthermore, three performance metrics of Channel MAC—throughput, fairness, and delay—are analysed in single hop and multihop scenarios using NS2 simulations. The simulation results show throughput performance improvement of up to 130% with Channel MAC over IEEE 802.11. We also show that the severe resource starvation problem (unfairness) of IEEE 802.11 in some network scenarios is reduced by the Channel MAC mechanism.

Access to environmental resources and physical activity levels of adults in Hawaii.

PubMed

Geller, Karly S; Nigg, Claudio R; Ollberding, Nicholas J; Motl, Robert W; Horwath, Caroline; Dishman, Rodney K

2015-03-01

Examine associations between physical activity (PA) and spatial accessibility to environmental PA resources in Hawaii. Metabolic equivalents (METs) of mild, moderate, and strenuous PA were compared for accessibility with environmental PA resources within a population-based sample of Hawaiian adults (n = 381). Multiple linear regression estimated differences in PA levels for residing further from a PA resource or residing in an area with a greater number of resources. No associations were found in the total sample. Analyses within subsamples stratified by ethnicity revealed that greater spatial accessibility to a PA resource was positively associated with strenuous PA among Caucasians (P = .04) but negatively associated with moderate PA among Native Hawaiians (P = .00). The lack of association in the total sample may be a consequence of Hawaii's unique environment. Results of stratified sample analyses are unique, providing groundwork for future examinations within parallel environments and among similar ethnic groups. © 2012 APJPH.

Distributed Space Mission Design for Earth Observation Using Model-Based Performance Evaluation

NASA Technical Reports Server (NTRS)

Nag, Sreeja; LeMoigne-Stewart, Jacqueline; Cervantes, Ben; DeWeck, Oliver

2015-01-01

Distributed Space Missions (DSMs) are gaining momentum in their application to earth observation missions owing to their unique ability to increase observation sampling in multiple dimensions. DSM design is a complex problem with many design variables, multiple objectives determining performance and cost and emergent, often unexpected, behaviors. There are very few open-access tools available to explore the tradespace of variables, minimize cost and maximize performance for pre-defined science goals, and therefore select the most optimal design. This paper presents a software tool that can multiple DSM architectures based on pre-defined design variable ranges and size those architectures in terms of predefined science and cost metrics. The tool will help a user select Pareto optimal DSM designs based on design of experiments techniques. The tool will be applied to some earth observation examples to demonstrate its applicability in making some key decisions between different performance metrics and cost metrics early in the design lifecycle.

Using Multiple Measures to Make Math Placement Decisions: Implications for Access and Success in Community Colleges

ERIC Educational Resources Information Center

Ngo, Federick; Kwon, William W.

2015-01-01

Community college students are often placed in developmental math courses based on the results of a single placement test. However, concerns about accurate placement have recently led states and colleges across the country to consider using other measures to inform placement decisions. While the relationships between college outcomes and such…

Partnering with Carryouts: Implementation of a Food Environment Intervention Targeting Youth Obesity

ERIC Educational Resources Information Center

Perepezko, K.; Tingey, L.; Sato, P.; Rastatter, S.; Ruggiero, C.; Gittelsohn, J.

2018-01-01

Youth obesity is a major public health problem in the United States, especially among urban-based, minority youth. The B'More Healthy Communities for Kids (BHCK) trial worked at multiple levels of the food environment, including carryouts, to increase access to and demand for healthy, affordable foods. The objective of this article is to describe…

Binary Sequences for Spread-Spectrum Multiple-Access Communication

DTIC Science & Technology

1977-08-01

Massey, J. L., and Uhran, J. J., Jr., "Sub-baud coding," Proceedings of the Thirteenth Annual Allerton Conference on Circuit and System Theory, pp. 539...sequences in a multipl.e access environment," Proceedings of the Thirteenth Annual AIlerton Conference on Circuit and System Theory, pp. 21-27, October...34 Proceedings of the Thirteenth Annual Allertcn Conference on Circuit and System Theory, pp. 548-559, October 1975. Yao, K., *Performance bounds on

Controlling the joint local false discovery rate is more powerful than meta-analysis methods in joint analysis of summary statistics from multiple genome-wide association studies.

PubMed

Jiang, Wei; Yu, Weichuan

2017-02-15

In genome-wide association studies (GWASs) of common diseases/traits, we often analyze multiple GWASs with the same phenotype together to discover associated genetic variants with higher power. Since it is difficult to access data with detailed individual measurements, summary-statistics-based meta-analysis methods have become popular to jointly analyze datasets from multiple GWASs. In this paper, we propose a novel summary-statistics-based joint analysis method based on controlling the joint local false discovery rate (Jlfdr). We prove that our method is the most powerful summary-statistics-based joint analysis method when controlling the false discovery rate at a certain level. In particular, the Jlfdr-based method achieves higher power than commonly used meta-analysis methods when analyzing heterogeneous datasets from multiple GWASs. Simulation experiments demonstrate the superior power of our method over meta-analysis methods. Also, our method discovers more associations than meta-analysis methods from empirical datasets of four phenotypes. The R-package is available at: http://bioinformatics.ust.hk/Jlfdr.html . eeyu@ust.hk. Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

Evaluation of 19,460 Wheat Accessions Conserved in the Indian National Genebank to Identify New Sources of Resistance to Rust and Spot Blotch Diseases.

PubMed

Kumar, Sundeep; Archak, Sunil; Tyagi, R K; Kumar, Jagdish; Vk, Vikas; Jacob, Sherry R; Srinivasan, Kalyani; Radhamani, J; Parimalan, R; Sivaswamy, M; Tyagi, Sandhya; Yadav, Mamata; Kumari, Jyotisna; Deepali; Sharma, Sandeep; Bhagat, Indoo; Meeta, Madhu; Bains, N S; Chowdhury, A K; Saha, B C; Bhattacharya, P M; Kumari, Jyoti; Singh, M C; Gangwar, O P; Prasad, P; Bharadwaj, S C; Gogoi, Robin; Sharma, J B; Gm, Sandeep Kumar; Saharan, M S; Bag, Manas; Roy, Anirban; Prasad, T V; Sharma, R K; Dutta, M; Sharma, Indu; Bansal, K C

2016-01-01

A comprehensive germplasm evaluation study of wheat accessions conserved in the Indian National Genebank was conducted to identify sources of rust and spot blotch resistance. Genebank accessions comprising three species of wheat-Triticum aestivum, T. durum and T. dicoccum were screened sequentially at multiple disease hotspots, during the 2011-14 crop seasons, carrying only resistant accessions to the next step of evaluation. Wheat accessions which were found to be resistant in the field were then assayed for seedling resistance and profiled using molecular markers. In the primary evaluation, 19,460 accessions were screened at Wellington (Tamil Nadu), a hotspot for wheat rusts. We identified 4925 accessions to be resistant and these were further evaluated at Gurdaspur (Punjab), a hotspot for stripe rust and at Cooch Behar (West Bengal), a hotspot for spot blotch. The second round evaluation identified 498 accessions potentially resistant to multiple rusts and 868 accessions potentially resistant to spot blotch. Evaluation of rust resistant accessions for seedling resistance against seven virulent pathotypes of three rusts under artificial epiphytotic conditions identified 137 accessions potentially resistant to multiple rusts. Molecular analysis to identify different combinations of genetic loci imparting resistance to leaf rust, stem rust, stripe rust and spot blotch using linked molecular markers, identified 45 wheat accessions containing known resistance genes against all three rusts as well as a QTL for spot blotch resistance. The resistant germplasm accessions, particularly against stripe rust, identified in this study can be excellent potential candidates to be employed for breeding resistance into the background of high yielding wheat cultivars through conventional or molecular breeding approaches, and are expected to contribute toward food security at national and global levels.

Evaluation of 19,460 Wheat Accessions Conserved in the Indian National Genebank to Identify New Sources of Resistance to Rust and Spot Blotch Diseases

PubMed Central

Jacob, Sherry R.; Srinivasan, Kalyani; Radhamani, J.; Parimalan, R.; Sivaswamy, M.; Tyagi, Sandhya; Yadav, Mamata; Kumari, Jyotisna; Deepali; Sharma, Sandeep; Bhagat, Indoo; Meeta, Madhu; Bains, N. S.; Chowdhury, A. K.; Saha, B. C.; Bhattacharya, P. M.; Kumari, Jyoti; Singh, M. C.; Gangwar, O. P.; Prasad, P.; Bharadwaj, S. C.; Gogoi, Robin; Sharma, J. B.; GM, Sandeep Kumar; Saharan, M. S.; Bag, Manas; Roy, Anirban; Prasad, T. V.; Sharma, R. K.; Dutta, M.; Sharma, Indu; Bansal, K. C.

2016-01-01

A comprehensive germplasm evaluation study of wheat accessions conserved in the Indian National Genebank was conducted to identify sources of rust and spot blotch resistance. Genebank accessions comprising three species of wheat–Triticum aestivum, T. durum and T. dicoccum were screened sequentially at multiple disease hotspots, during the 2011–14 crop seasons, carrying only resistant accessions to the next step of evaluation. Wheat accessions which were found to be resistant in the field were then assayed for seedling resistance and profiled using molecular markers. In the primary evaluation, 19,460 accessions were screened at Wellington (Tamil Nadu), a hotspot for wheat rusts. We identified 4925 accessions to be resistant and these were further evaluated at Gurdaspur (Punjab), a hotspot for stripe rust and at Cooch Behar (West Bengal), a hotspot for spot blotch. The second round evaluation identified 498 accessions potentially resistant to multiple rusts and 868 accessions potentially resistant to spot blotch. Evaluation of rust resistant accessions for seedling resistance against seven virulent pathotypes of three rusts under artificial epiphytotic conditions identified 137 accessions potentially resistant to multiple rusts. Molecular analysis to identify different combinations of genetic loci imparting resistance to leaf rust, stem rust, stripe rust and spot blotch using linked molecular markers, identified 45 wheat accessions containing known resistance genes against all three rusts as well as a QTL for spot blotch resistance. The resistant germplasm accessions, particularly against stripe rust, identified in this study can be excellent potential candidates to be employed for breeding resistance into the background of high yielding wheat cultivars through conventional or molecular breeding approaches, and are expected to contribute toward food security at national and global levels. PMID:27942031

Linking Fine-Scale Observations and Model Output with Imagery at Multiple Scales

NASA Astrophysics Data System (ADS)

Sadler, J.; Walthall, C. L.

2014-12-01

The development and implementation of a system for seasonal worldwide agricultural yield estimates is underway with the international Group on Earth Observations GeoGLAM project. GeoGLAM includes a research component to continually improve and validate its algorithms. There is a history of field measurement campaigns going back decades to draw upon for ways of linking surface measurements and model results with satellite observations. Ground-based, in-situ measurements collected by interdisciplinary teams include yields, model inputs and factors affecting scene radiation. Data that is comparable across space and time with careful attention to calibration is essential for the development and validation of agricultural applications of remote sensing. Data management to ensure stewardship, availability and accessibility of the data are best accomplished when considered an integral part of the research. The expense and logistical challenges of field measurement campaigns can be cost-prohibitive and because of short funding cycles for research, access to consistent, stable study sites can be lost. The use of a dedicated staff for baseline data needed by multiple investigators, and conducting measurement campaigns using existing measurement networks such as the USDA Long Term Agroecosystem Research network can fulfill these needs and ensure long-term access to study sites.

Tunneling and Origin of Large Access Resistance in Layered-Crystal Organic Transistors

NASA Astrophysics Data System (ADS)

Hamai, Takamasa; Arai, Shunto; Minemawari, Hiromi; Inoue, Satoru; Kumai, Reiji; Hasegawa, Tatsuo

2017-11-01

Layered crystallinity of organic semiconductors is crucial to obtaining high-performance organic thin-film transistors (OTFTs), as it allows both smooth-channel-gate-insulator interface formation and efficient two-dimensional carrier transport along the interface. However, the role of vertical transport across the crystalline molecular layers in device operations has not been a crucial subject so far. Here, we show that the interlayer carrier transport causes unusual nonlinear current-voltage characteristics and enormous access resistance in extremely high-quality single-crystal OTFTs based on 2-decyl-7-phenyl[1]-benzothieno[3 ,2 -b ][1]benzothiophene (Ph -BTBT -C10 ) that involve inherent multiple semiconducting π -conjugated layers interposed, respectively, by electrically inert alkyl-chain layers. The output characteristics present layer-number (n )-dependent nonlinearity that becomes more evident at larger n (1 ≤n ≤15 ), demonstrating tunneling across multiple alkyl-chain layers. The n -dependent device mobility and four-probe measurements reveal that the alkyl-chain layers generate a large access resistance that suppresses the device mobility from the intrinsic value of about 20 cm2 V-1 s-1 . Our findings clarify the reason why device characteristics are distributed in single-crystal OTFTs.

Heterodyne detection using spectral line pairing for spectral phase encoding optical code division multiple access and dynamic dispersion compensation.

PubMed

Yang, Yi; Foster, Mark; Khurgin, Jacob B; Cooper, A Brinton

2012-07-30

A novel coherent optical code-division multiple access (OCDMA) scheme is proposed that uses spectral line pairing to generate signals suitable for heterodyne decoding. Both signal and local reference are transmitted via a single optical fiber and a simple balanced receiver performs sourceless heterodyne detection, canceling speckle noise and multiple-access interference (MAI). To validate the idea, a 16 user fully loaded phase encoded system is simulated. Effects of fiber dispersion on system performance are studied as well. Both second and third order dispersion management is achieved by using a spectral phase encoder to adjust phase shifts of spectral components at the optical network unit (ONU).

An Ultrasonic Multiple-Access Ranging Core Based on Frequency Shift Keying Towards Indoor Localization

PubMed Central

Segers, Laurent; Van Bavegem, David; De Winne, Sam; Braeken, An; Touhafi, Abdellah; Steenhaut, Kris

2015-01-01

This paper describes a new approach and implementation methodology for indoor ranging based on the time difference of arrival using code division multiple access with ultrasound signals. A novel implementation based on a field programmable gate array using finite impulse response filters and an optimized correlation demodulator implementation for ultrasound orthogonal signals is developed. Orthogonal codes are modulated onto ultrasound signals using frequency shift keying with carrier frequencies of 24.5 kHz and 26 kHz. This implementation enhances the possibilities for real-time, embedded and low-power tracking of several simultaneous transmitters. Due to the high degree of parallelism offered by field programmable gate arrays, up to four transmitters can be tracked simultaneously. The implementation requires at most 30% of the available logic gates of a Spartan-6 XC6SLX45 device and is evaluated on accuracy and precision through several ranging topologies. In the first topology, the distance between one transmitter and one receiver is evaluated. Afterwards, ranging analyses are applied between two simultaneous transmitters and one receiver. Ultimately, the position of the receiver against four transmitters using trilateration is also demonstrated. Results show enhanced distance measurements with distances ranging from a few centimeters up to 17 m, while keeping a centimeter-level accuracy. PMID:26263986

Phylogeny and evolutionary histories of Pyrus L. revealed by phylogenetic trees and networks based on data from multiple DNA sequences.

PubMed

Zheng, Xiaoyan; Cai, Danying; Potter, Daniel; Postman, Joseph; Liu, Jing; Teng, Yuanwen

2014-11-01

Reconstructing the phylogeny of Pyrus has been difficult due to the wide distribution of the genus and lack of informative data. In this study, we collected 110 accessions representing 25 Pyrus species and constructed both phylogenetic trees and phylogenetic networks based on multiple DNA sequence datasets. Phylogenetic trees based on both cpDNA and nuclear LFY2int2-N (LN) data resulted in poor resolution, especially, only five primary species were monophyletic in the LN tree. A phylogenetic network of LN suggested that reticulation caused by hybridization is one of the major evolutionary processes for Pyrus species. Polytomies of the gene trees and star-like structure of cpDNA networks suggested rapid radiation is another major evolutionary process, especially for the occidental species. Pyrus calleryana and P. regelii were the earliest diverged Pyrus species. Two North African species, P. cordata, P. spinosa and P. betulaefolia were descendent of primitive stock Pyrus species and still share some common molecular characters. Southwestern China, where a large number of P. pashia populations are found, is probably the most important diversification center of Pyrus. More accessions and nuclear genes are needed for further understanding the evolutionary histories of Pyrus. Copyright © 2014 Elsevier Inc. All rights reserved.

Equalizing access to pandemic influenza vaccines through optimal allocation to public health distribution points.

PubMed

Huang, Hsin-Chan; Singh, Bismark; Morton, David P; Johnson, Gregory P; Clements, Bruce; Meyers, Lauren Ancel

2017-01-01

Vaccines are arguably the most important means of pandemic influenza mitigation. However, as during the 2009 H1N1 pandemic, mass immunization with an effective vaccine may not begin until a pandemic is well underway. In the U.S., state-level public health agencies are responsible for quickly and fairly allocating vaccines as they become available to populations prioritized to receive vaccines. Allocation decisions can be ethically and logistically complex, given several vaccine types in limited and uncertain supply and given competing priority groups with distinct risk profiles and vaccine acceptabilities. We introduce a model for optimizing statewide allocation of multiple vaccine types to multiple priority groups, maximizing equal access. We assume a large fraction of available vaccines are distributed to healthcare providers based on their requests, and then optimize county-level allocation of the remaining doses to achieve equity. We have applied the model to the state of Texas, and incorporated it in a Web-based decision-support tool for the Texas Department of State Health Services (DSHS). Based on vaccine quantities delivered to registered healthcare providers in response to their requests during the 2009 H1N1 pandemic, we find that a relatively small cache of discretionary doses (DSHS reserved 6.8% in 2009) suffices to achieve equity across all counties in Texas.

[Differences in access to Internet and Internet-based information seeking according to the type of psychiatric disorder].

PubMed

Brunault, P; Bray, A; Rerolle, C; Cognet, S; Gaillard, P; El-Hage, W

2017-04-01

Internet has become a major tool for patients to search for health-related information and to communicate on health. We currently lack data on how patients with psychiatric disorders access and use Internet to search for information on their mental health. This study aimed to assess, in patients followed for a psychiatric disorder (schizophrenia, bipolar disorder, mood and anxiety disorder, substance-related and addictive disorders and eating disorders), prevalence of Internet access and use, and patient expectations and needs regarding the use of Internet to search for mental-health information depending on the psychiatric disorder. We conducted this cross-sectional study between May 2013 and July 2013 in 648 patients receiving psychiatric care in 8 hospitals from the Region Centre, France. We used multivariate logistic regression adjusted for age, gender, socio-educational level and professional status to compare use, expectations and needs regarding Internet-based information about the patient's psychiatric disorder (65-items self-administered questionnaires) as a function of the psychiatric disorders. We identified patients clusters with multiple correspondence analysis and ascending hierarchical classification. Although 65.6% of our population accessed Internet at home, prevalence for Internet access varied depending on the type of psychiatric disorder and was much more related to limited access to a computer and low income than to a lack of interest in the Internet. Most of the patients who used Internet were interested in having access to reliable Internet-based information on their health (76.8%), and most used Internet to search for Internet based health-information about their psychiatric disorder (58.8%). We found important differences in terms of expectations and needs depending on the patient's psychiatric disorder (e.g., higher interest in Internet-based information among patients with bipolar disorder, substance-related and addictive disorders and eating disorders). We identified three clusters: younger patients with depressive or anxiety disorders and higher Internet access and Internet use; older patients with low socio-economical status and low Internet access and Internet use; patients receiving long-term care for schizophrenia, with low Internet access and Internet use. Patients with psychiatric disorders reported average use, needs and expectations for Internet-based health information comparable to the overall population. However, Internet use, needs and expectations for Internet-based mental health information differed between patients depending on their psychiatric disorder. Internet-based information and communication for mental health should be designed specifically for each psychiatric disorder. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

A geodata warehouse: Using denormalisation techniques as a tool for delivering spatially enabled integrated geological information to geologists

NASA Astrophysics Data System (ADS)

Kingdon, Andrew; Nayembil, Martin L.; Richardson, Anne E.; Smith, A. Graham

2016-11-01

New requirements to understand geological properties in three dimensions have led to the development of PropBase, a data structure and delivery tools to deliver this. At the BGS, relational database management systems (RDBMS) has facilitated effective data management using normalised subject-based database designs with business rules in a centralised, vocabulary controlled, architecture. These have delivered effective data storage in a secure environment. However, isolated subject-oriented designs prevented efficient cross-domain querying of datasets. Additionally, the tools provided often did not enable effective data discovery as they struggled to resolve the complex underlying normalised structures providing poor data access speeds. Users developed bespoke access tools to structures they did not fully understand sometimes delivering them incorrect results. Therefore, BGS has developed PropBase, a generic denormalised data structure within an RDBMS to store property data, to facilitate rapid and standardised data discovery and access, incorporating 2D and 3D physical and chemical property data, with associated metadata. This includes scripts to populate and synchronise the layer with its data sources through structured input and transcription standards. A core component of the architecture includes, an optimised query object, to deliver geoscience information from a structure equivalent to a data warehouse. This enables optimised query performance to deliver data in multiple standardised formats using a web discovery tool. Semantic interoperability is enforced through vocabularies combined from all data sources facilitating searching of related terms. PropBase holds 28.1 million spatially enabled property data points from 10 source databases incorporating over 50 property data types with a vocabulary set that includes 557 property terms. By enabling property data searches across multiple databases PropBase has facilitated new scientific research, previously considered impractical. PropBase is easily extended to incorporate 4D data (time series) and is providing a baseline for new "big data" monitoring projects.

Variation in geographic access to chemotherapy by definitions of providers and service locations: a population-based observational study.

PubMed

Schroeder, Mary C; Chapman, Cole G; Nattinger, Matthew C; Halfdanarson, Thorvardur R; Abu-Hejleh, Taher; Tien, Yu-Yu; Brooks, John M

2016-07-18

An aging population, with its associated rise in cancer incidence and strain on the oncology workforce, will continue to motivate patients, healthcare providers and policy makers to better understand the existing and growing challenges of access to chemotherapy. Administrative data, and SEER-Medicare data in particular, have been used to assess patterns of healthcare utilization because of its rich information regarding patients, their treatments, and their providers. To create measures of geographic access to chemotherapy, patients and oncologists must first be identified. Others have noted that identifying chemotherapy providers from Medicare claims is not always straightforward, as providers may report multiple or incorrect specialties and/or practice in multiple locations. Although previous studies have found that specialty codes alone fail to identify all oncologists, none have assessed whether various methods of identifying chemotherapy providers and their locations affect estimates of geographic access to care. SEER-Medicare data was used to identify patients, physicians, and chemotherapy use in this population-based observational study. We compared two measures of geographic access to chemotherapy, local area density and distance to nearest provider, across two definitions of chemotherapy provider (identified by specialty codes or billing codes) and two definitions of chemotherapy service location (where chemotherapy services were proven to be or possibly available) using descriptive statistics. Access measures were mapped for three representative registries. In our sample, 57.2 % of physicians who submitted chemotherapy claims reported a specialty of hematology/oncology or medical oncology. These physicians were associated with 91.0 % of the chemotherapy claims. When providers were identified through billing codes instead of specialty codes, an additional 50.0 % of beneficiaries (from 23.8 % to 35.7 %) resided in the same ZIP code as a chemotherapy provider. Beneficiaries were also 1.3 times closer to a provider, in terms of driving time. Our access measures did not differ significantly across definitions of service location. Measures of geographic access to care were sensitive to definitions of chemotherapy providers; far more providers were identified through billing codes than specialty codes. They were not sensitive to definitions of service locations, as providers, regardless of how they are identified, generally provided chemotherapy at each of their practice locations.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Veseli, S.

As the number of sites deploying and adopting EPICS Version 4 grows, so does the need to support PV Access from multiple languages. Especially important are the widely used scripting languages that tend to reduce both software development time and the learning curve for new users. In this paper we describe PvaPy, a Python API for the EPICS PV Access protocol and its accompanying structured data API. Rather than implementing the protocol itself in Python, PvaPy wraps the existing EPICS Version 4 C++ libraries using the Boost.Python framework. This approach allows us to benefit from the existing code base andmore » functionality, and to significantly reduce the Python API development effort. PvaPy objects are based on Python dictionaries and provide users with the ability to access even the most complex of PV Data structures in a relatively straightforward way. Its interfaces are easy to use, and include support for advanced EPICS Version 4 features such as implementation of client and server Remote Procedure Calls (RPC).« less

Listening to rural Hispanic immigrants in the Midwest: a community-based participatory assessment of major barriers to health care access and use.

PubMed

Cristancho, Sergio; Garces, D Marcela; Peters, Karen E; Mueller, Benjamin C

2008-05-01

Hispanic immigrants are increasingly residing in rural communities, including in the midwestern United States. Limitations in the ability of rural Hispanics to access and utilize health care contribute to patterns of poor health and health disparity. A conceptual model of "vulnerability" guides this community-based participatory assessment project designed to explore rural Hispanics' perceived barriers to accessing and utilizing health care. Findings from a series of 19 focus groups with 181 participants from three communities in the upper Midwest identified perceived barriers at the individual and health care system levels. The most commonly perceived barriers were the lack of and limitations in health insurance coverage, high costs of health care services, communication issues involving patients and providers, legal status/discrimination, and transportation concerns. Findings imply that these barriers could be addressed using multiple educational and health service delivery policy-related strategies that consider the vulnerable nature of this growing population.

Towards ubiquitous access of computer-assisted surgery systems.

PubMed

Liu, Hui; Lufei, Hanping; Shi, Weishong; Chaudhary, Vipin

2006-01-01

Traditional stand-alone computer-assisted surgery (CAS) systems impede the ubiquitous and simultaneous access by multiple users. With advances in computing and networking technologies, ubiquitous access to CAS systems becomes possible and promising. Based on our preliminary work, CASMIL, a stand-alone CAS server developed at Wayne State University, we propose a novel mobile CAS system, UbiCAS, which allows surgeons to retrieve, review and interpret multimodal medical images, and to perform some critical neurosurgical procedures on heterogeneous devices from anywhere at anytime. Furthermore, various optimization techniques, including caching, prefetching, pseudo-streaming-model, and compression, are used to guarantee the QoS of the UbiCAS system. UbiCAS enables doctors at remote locations to actively participate remote surgeries, share patient information in real time before, during, and after the surgery.

Hybrid Multiagent System for Automatic Object Learning Classification

NASA Astrophysics Data System (ADS)

Gil, Ana; de La Prieta, Fernando; López, Vivian F.

The rapid evolution within the context of e-learning is closely linked to international efforts on the standardization of learning object metadata, which provides learners in a web-based educational system with ubiquitous access to multiple distributed repositories. This article presents a hybrid agent-based architecture that enables the recovery of learning objects tagged in Learning Object Metadata (LOM) and provides individualized help with selecting learning materials to make the most suitable choice among many alternatives.

Comparison of CDMA and FDMA for the MobileStar(sm) system

NASA Technical Reports Server (NTRS)

Jacobs, I. M.; Gilhousen, K. S.; Weaver, L. A.; Renshaw, K.; Murphy, T.

1988-01-01

Spread-spectrum code division multiple access (CDMA) and single channel per carrier frequency division multiple access (FDMA) systems are compared for spectrum efficiency. CDMA is shown to have greater maximum throughput than FDMA for the MobileStar(sm) system which uses digital voice activated carriers and directive circularly polarized satellite antennas.

Transparent mediation-based access to multiple yeast data sources using an ontology driven interface.

PubMed

Briache, Abdelaali; Marrakchi, Kamar; Kerzazi, Amine; Navas-Delgado, Ismael; Rossi Hassani, Badr D; Lairini, Khalid; Aldana-Montes, José F

2012-01-25

Saccharomyces cerevisiae is recognized as a model system representing a simple eukaryote whose genome can be easily manipulated. Information solicited by scientists on its biological entities (Proteins, Genes, RNAs...) is scattered within several data sources like SGD, Yeastract, CYGD-MIPS, BioGrid, PhosphoGrid, etc. Because of the heterogeneity of these sources, querying them separately and then manually combining the returned results is a complex and time-consuming task for biologists most of whom are not bioinformatics expert. It also reduces and limits the use that can be made on the available data. To provide transparent and simultaneous access to yeast sources, we have developed YeastMed: an XML and mediator-based system. In this paper, we present our approach in developing this system which takes advantage of SB-KOM to perform the query transformation needed and a set of Data Services to reach the integrated data sources. The system is composed of a set of modules that depend heavily on XML and Semantic Web technologies. User queries are expressed in terms of a domain ontology through a simple form-based web interface. YeastMed is the first mediation-based system specific for integrating yeast data sources. It was conceived mainly to help biologists to find simultaneously relevant data from multiple data sources. It has a biologist-friendly interface easy to use. The system is available at http://www.khaos.uma.es/yeastmed/.

Multiple Intimate Partner Violence Experiences: Knowledge, Access, Utilization and Barriers to Utilization of Resources by Women of the African Diaspora.

PubMed

Sabri, Bushra; Huerta, Julia; Alexander, Kamila A; St Vil, Noelle M; Campbell, Jacquelyn C; Callwood, Gloria B

2015-11-01

This study examined knowledge, access, utilization, and barriers to use of resources among Black women exposed to multiple types of intimate partner violence in Baltimore, Maryland and the U.S. Virgin Islands (USVI). We analyzed quantitative survey data collected by 163 women recruited from primary care, prenatal or family planning clinics in Baltimore and the USVI. In addition we analyzed qualitative data from in-depth interviews with 11 women. Quantitative data were analyzed using descriptive statistics and qualitative data were analyzed using thematic analysis. A substantial proportion of Black women with multiple types of violence experiences lacked knowledge of, did not have access to, and did not use resources. Barriers to resource use were identified at the individual, relationship, and community levels. There is need for programs to develop awareness, promote access and utilization of resources, and eliminate barriers to resource use among abused Black women.

Distributed reservation control protocols for random access broadcasting channels

NASA Technical Reports Server (NTRS)

Greene, E. P.; Ephremides, A.

1981-01-01

Attention is given to a communication network consisting of an arbitrary number of nodes which can communicate with each other via a time-division multiple access (TDMA) broadcast channel. The reported investigation is concerned with the development of efficient distributed multiple access protocols for traffic consisting primarily of single packet messages in a datagram mode of operation. The motivation for the design of the protocols came from the consideration of efficient multiple access utilization of moderate to high bandwidth (4-40 Mbit/s capacity) communication satellite channels used for the transmission of short (1000-10,000 bits) fixed length packets. Under these circumstances, the ratio of roundtrip propagation time to packet transmission time is between 100 to 10,000. It is shown how a TDMA channel can be adaptively shared by datagram traffic and constant bandwidth users such as in digital voice applications. The distributed reservation control protocols described are a hybrid between contention and reservation protocols.

The relationship between employment and health and health care among working-age adults with and without disabilities in the United States.

PubMed

Reichard, Amanda; Stransky, Michelle; Brucker, Debra; Houtenville, Andrew

2018-05-20

To better understand the relationship between employment and health and health care for people with disabilities in the United States (US). We pooled US Medical Expenditure Panel Survey (2004-2010) data to examine health status, and access to health care among working-age adults, comparing people with physical disabilities or multiple disabilities to people without disabilities, based on their employment status. Logistic regression and least squares regression were conducted, controlling for sociodemographics, health insurance (when not the outcome), multiple chronic conditions, and need for assistance. Employment was inversely related to access to care, insurance, and obesity. Yet, people with disabilities employed in the past year reported better general and mental health than their peers with the same disabilities who were not employed. Those who were employed were more likely to have delayed/forgone necessary care, across disability groups. Part-time employment, especially for people with multiple limitations, was associated with better health and health care outcomes than full-time employment. Findings highlight the importance of addressing employment-related causes of delayed or foregone receipt of necessary care (e.g., flex-time for attending appointments) that exist for all workers, especially those with physical or multiple disabilities. Implications for rehabilitation These findings demonstrate that rehabilitation professionals who are seeking to support employment for persons with physical limitations need to ensure that overall health concerns are adequately addressed, both for those seeking employment and for those who are currently employed. Assisting clients in prioritizing health equally with employment can ensure that both areas receive sufficient attention. Engaging with employers to develop innovative practices to improve health, health behaviors and access to care for employees with disabilities can decrease turnover, increase productivity, and ensure longer job tenure.

Characterization of dual-polarization LTE radio over a free-space optical turbulence channel.

PubMed

Bohata, J; Zvanovec, S; Korinek, T; Mansour Abadi, M; Ghassemlooy, Z

2015-08-10

A dual polarization (DP) radio over a free-space optical (FSO) communication link using a long-term evolution (LTE) radio signal is proposed and analyzed under different turbulence channel conditions. Radio signal transmission over the DP FSO channel is experimentally verified by means of error vector magnitude (EVM) statistics. We demonstrate that such a system, employing a 64 quadrature amplitude modulation at the frequency bands of 800 MHz and 2.6 GHz, evinces reliability with <8% of EVM in a turbulent channel. Based on the results, we show that transmitting the LTE signal over the FSO channel is a potential solution for last-mile access or backbone networks, when using multiple-input multiple-output based DP signals.

2x2 MIMO-OFDM Gigabit fiber-wireless access system based on polarization division multiplexed WDM-PON.

PubMed

Deng, Lei; Pang, Xiaodan; Zhao, Ying; Othman, M B; Jensen, Jesper Bevensee; Zibar, Darko; Yu, Xianbin; Liu, Deming; Monroy, Idelfonso Tafur

2012-02-13

We propose a spectral efficient radio over wavelength division multiplexed passive optical network (WDM-PON) system by combining optical polarization division multiplexing (PDM) and wireless multiple input multiple output (MIMO) spatial multiplexing techniques. In our experiment, a training-based zero forcing (ZF) channel estimation algorithm is designed to compensate the polarization rotation and wireless multipath fading. A 797 Mb/s net data rate QPSK-OFDM signal with error free (<1 × 10(5)) performance and a 1.59 Gb/s net data rate 16QAM-OFDM signal with BER performance of 1.2 × 10(2) are achieved after transmission of 22.8 km single mode fiber followed by 3 m and 1 m air distances, respectively.

IPAT: a freely accessible software tool for analyzing multiple patent documents with inbuilt landscape visualizer.

PubMed

Ajay, Dara; Gangwal, Rahul P; Sangamwar, Abhay T

2015-01-01

Intelligent Patent Analysis Tool (IPAT) is an online data retrieval tool, operated based on text mining algorithm to extract specific patent information in a predetermined pattern into an Excel sheet. The software is designed and developed to retrieve and analyze technology information from multiple patent documents and generate various patent landscape graphs and charts. The software is C# coded in visual studio 2010, which extracts the publicly available patent information from the web pages like Google Patent and simultaneously study the various technology trends based on user-defined parameters. In other words, IPAT combined with the manual categorization will act as an excellent technology assessment tool in competitive intelligence and due diligence for predicting the future R&D forecast.

Adolescents and access to health care.

PubMed Central

Klein, J. D.; Slap, G. B.; Elster, A. B.; Cohn, S. E.

1993-01-01

The developmental characteristics and health behaviors of adolescents make the availability of certain services--including reproductive health services, diagnosis and treatment of sexually transmitted disease, mental health and substance abuse counseling and treatment--critically important. Furthermore, to serve adolescents appropriately, services must be available in a wide range of health care settings, including community-based adolescent health, family planning and public health clinics, school-based and school-linked health clinics, physicians' offices, HMOs, and hospitals. National, authoritative content standards (for example, the American Medical Association's Guidelines for Adolescent Preventive Services (GAPS), a multispecialty, interdisciplinary guideline for a package of clinical preventive services for adolescents may increase the possibility that insurers will cover adolescent preventive services, and that these services will become part of health professionals' curricula and thus part of routine practice. However, additional and specific guidelines mandating specific services that must be available to adolescents in clinical settings (whether in schools or in communities) are also needed. Although local government, parents, providers, and schools must assume responsibility for ensuring that health services are available and accessible to adolescents, federal and state financing mandates are also needed to assist communities and providers in achieving these goals. The limitations in what even comprehensive programs currently are able to provide, and the dismally low rates of preventive service delivery to adolescents, suggests that adolescents require multiple points of access to comprehensive, coordinated services, and that preventive health interventions must be actively and increasingly integrated across health care, school, and community settings. Unless access issues are dealt with in a rational, coordinated fashion, America's adolescents will not have access to appropriate health services. Current efforts to minimize current health care expenditures through managed care programs inevitably conflict with efforts to deliver comprehensive preventive services to all adolescents. Use of multiple sites may not represent inadequate access to care. However, as managed care reimbursement continues to expand, school-based clinics and free-standing adolescent health programs increasingly report decreases in reimbursement without a change in demand for services. The Office of Technology Assessment study called for explicit funding and expansion of services for America's youth; since then, a federal Office of Adolescent Health has been authorized, and, by the time this reaches print, should have received appropriations and been staffed. Dryfoos has called for expansion to nearly 5000 comprehensive programs in the coming years.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:8148842

Efficiently sphere-decodable physical layer transmission schemes for wireless storage networks

NASA Astrophysics Data System (ADS)

Lu, Hsiao-Feng Francis; Barreal, Amaro; Karpuk, David; Hollanti, Camilla

2016-12-01

Three transmission schemes over a new type of multiple-access channel (MAC) model with inter-source communication links are proposed and investigated in this paper. This new channel model is well motivated by, e.g., wireless distributed storage networks, where communication to repair a lost node takes place from helper nodes to a repairing node over a wireless channel. Since in many wireless networks nodes can come and go in an arbitrary manner, there must be an inherent capability of inter-node communication between every pair of nodes. Assuming that communication is possible between every pair of helper nodes, the newly proposed schemes are based on various smart time-sharing and relaying strategies. In other words, certain helper nodes will be regarded as relays, thereby converting the conventional uncooperative multiple-access channel to a multiple-access relay channel (MARC). The diversity-multiplexing gain tradeoff (DMT) of the system together with efficient sphere-decodability and low structural complexity in terms of the number of antennas required at each end is used as the main design objectives. While the optimal DMT for the new channel model is fully open, it is shown that the proposed schemes outperform the DMT of the simple time-sharing protocol and, in some cases, even the optimal uncooperative MAC DMT. While using a wireless distributed storage network as a motivating example throughout the paper, the MAC transmission techniques proposed here are completely general and as such applicable to any MAC communication with inter-source communication links.

iSERVO: Implementing the International Solid Earth Research Virtual Observatory by Integrating Computational Grid and Geographical Information Web Services

NASA Astrophysics Data System (ADS)

Aktas, Mehmet; Aydin, Galip; Donnellan, Andrea; Fox, Geoffrey; Granat, Robert; Grant, Lisa; Lyzenga, Greg; McLeod, Dennis; Pallickara, Shrideep; Parker, Jay; Pierce, Marlon; Rundle, John; Sayar, Ahmet; Tullis, Terry

2006-12-01

We describe the goals and initial implementation of the International Solid Earth Virtual Observatory (iSERVO). This system is built using a Web Services approach to Grid computing infrastructure and is accessed via a component-based Web portal user interface. We describe our implementations of services used by this system, including Geographical Information System (GIS)-based data grid services for accessing remote data repositories and job management services for controlling multiple execution steps. iSERVO is an example of a larger trend to build globally scalable scientific computing infrastructures using the Service Oriented Architecture approach. Adoption of this approach raises a number of research challenges in millisecond-latency message systems suitable for internet-enabled scientific applications. We review our research in these areas.

The Availability and Utility of Services to Address Risk Factors for Recidivism among Justice-Involved Veterans

PubMed Central

Blonigen, Daniel M.; Rodriguez, Allison L.; Manfredi, Luisa; Britt, Jessica; Nevedal, Andrea; Finlay, Andrea K.; Rosenthal, Joel; Smelson, David; Timko, Christine

2016-01-01

The availability and utility of services to address recidivism risk factors among justice-involved veterans is unknown. We explored these issues through qualitative interviews with 63 Specialists from the Department of Veterans Affairs’ (VA) Veterans Justice Programs. To guide the interviews, we utilized the Risk-Need-Responsivity (RNR) model of offender rehabilitation. Specialists reported that justice-involved veterans generally have access to services to address most RNR-based risk factors (substance abuse; lack of positive school/work involvement; family/marital dysfunction; lack of prosocial activities/interests), but have less access to services targeting risk factors of antisocial tendencies and associates and empirically-based treatments for recidivism in VA. Peer-based services, motivational interviewing/cognitive-behavioral therapy, and Veterans Treatment Courts were perceived as useful to address multiple risk factors. These findings highlight potential gaps in provision of evidence-based care to address recidivism among justice-involved veterans, as well as promising policy-based solutions that may have widespread impact on reducing recidivism in this population. PMID:26924887

System access control study

DOT National Transportation Integrated Search

1974-06-01

The report presents a summary of a study conducted for the Transportation Systems Center of promising access control techniques which are applicable to an aeronautical satellite system. Several frequency division multiple access (FDMA) and time divis...

On board processing for future satellite communications systems: Comparison of FDM, TDM and hybrid accessing schemes

NASA Technical Reports Server (NTRS)

Berk, G.; Jean, P. N.; Rotholz, E.

1982-01-01

Several satellite uplink and downlink accessing schemes for customer premises service are compared. Four conceptual system designs are presented: satellite-routed frequency division multiple access (FDMA), satellite-switched time division multiple access (TDMA), processor-routed TDMA, and frequency-routed TDMA, operating in the 30/20 GHz band. The designs are compared on the basis of estimated satellite weight, system capacity, power consumption, and cost. The systems are analyzed for fixed multibeam coverage of the continental United States. Analysis shows that the system capacity is limited by the available satellite resources and by the terminal size and cost.

Network-based drug discovery by integrating systems biology and computational technologies

PubMed Central

Leung, Elaine L.; Cao, Zhi-Wei; Jiang, Zhi-Hong; Zhou, Hua

2013-01-01

Network-based intervention has been a trend of curing systemic diseases, but it relies on regimen optimization and valid multi-target actions of the drugs. The complex multi-component nature of medicinal herbs may serve as valuable resources for network-based multi-target drug discovery due to its potential treatment effects by synergy. Recently, robustness of multiple systems biology platforms shows powerful to uncover molecular mechanisms and connections between the drugs and their targeting dynamic network. However, optimization methods of drug combination are insufficient, owning to lacking of tighter integration across multiple ‘-omics’ databases. The newly developed algorithm- or network-based computational models can tightly integrate ‘-omics’ databases and optimize combinational regimens of drug development, which encourage using medicinal herbs to develop into new wave of network-based multi-target drugs. However, challenges on further integration across the databases of medicinal herbs with multiple system biology platforms for multi-target drug optimization remain to the uncertain reliability of individual data sets, width and depth and degree of standardization of herbal medicine. Standardization of the methodology and terminology of multiple system biology and herbal database would facilitate the integration. Enhance public accessible databases and the number of research using system biology platform on herbal medicine would be helpful. Further integration across various ‘-omics’ platforms and computational tools would accelerate development of network-based drug discovery and network medicine. PMID:22877768

Cloud-based solution to identify statistically significant MS peaks differentiating sample categories.

PubMed

Ji, Jun; Ling, Jeffrey; Jiang, Helen; Wen, Qiaojun; Whitin, John C; Tian, Lu; Cohen, Harvey J; Ling, Xuefeng B

2013-03-23

Mass spectrometry (MS) has evolved to become the primary high throughput tool for proteomics based biomarker discovery. Until now, multiple challenges in protein MS data analysis remain: large-scale and complex data set management; MS peak identification, indexing; and high dimensional peak differential analysis with the concurrent statistical tests based false discovery rate (FDR). "Turnkey" solutions are needed for biomarker investigations to rapidly process MS data sets to identify statistically significant peaks for subsequent validation. Here we present an efficient and effective solution, which provides experimental biologists easy access to "cloud" computing capabilities to analyze MS data. The web portal can be accessed at http://transmed.stanford.edu/ssa/. Presented web application supplies large scale MS data online uploading and analysis with a simple user interface. This bioinformatic tool will facilitate the discovery of the potential protein biomarkers using MS.

Performance of Fourth-Grade Students with Learning Disabilities on Multiplication Facts Comparing Teacher-Mediated and Technology-Mediated Interventions: A Preliminary Investigation

ERIC Educational Resources Information Center

Bryant, Brian R.; Ok, Minwook; Kang, Eun Young; Kim, Min Kyung; Lang, Russell; Bryant, Diane Pedrotty; Pfannestiel, Kathleen

2015-01-01

Instructional applications (apps) are educational software programs that can be accessed via mobile technologies (e.g., iPad, smartphone) and used to help students acquire various academic skills, including mathematics. Although research suggests that app-based instruction (AI) can be effective, there is a paucity of research comparing AI, to…

Precise Interval Timer for Software Defined Radio

NASA Technical Reports Server (NTRS)

Pozhidaev, Aleksey (Inventor)

2014-01-01

A precise digital fractional interval timer for software defined radios which vary their waveform on a packet-by-packet basis. The timer allows for variable length in the preamble of the RF packet and allows to adjust boundaries of the TDMA (Time Division Multiple Access) Slots of the receiver of an SDR based on the reception of the RF packet of interest.

Inside the Digital Wild West: How School Leaders Both Access and Avoid Social Media

ERIC Educational Resources Information Center

Corrigan, Laurie; Robertson, Lorayne

2015-01-01

This study examines the roles of Canadian school leaders in response to the rising phenomenon of student use of social media which impacts school climate and safety. The use of social media has resulted in more online text and image-based communication to multiple users and less face-to-face communication with single users. Adolescent…

Physical World Hyperlinking: Can Computer-Based Instruction in a K-6 Educational Setting Be Easily Accessed through Tangible Tagged Objects

ERIC Educational Resources Information Center

Parton, Becky Sue; Hancock, Robert; Mihir, Mihir

2010-01-01

This paper examined multiple types of physical world hyperlinking hardware configurations for the purpose of determining an optimal reader/tag combination for K-6 student use. Both traditional barcode tags and two types of RFID (Radio Frequency Identification) tags were placed on tangible items. Students ranging from kindergarten to sixth grade…

Study of spread spectrum multiple access systems for satellite communications with overlay on current services

NASA Technical Reports Server (NTRS)

Ha, Tri T.; Pratt, Timothy

1989-01-01

The feasibility of using spread spectrum techniques to provide a low-cost multiple access system for a very large number of low data terminals was investigated. Two applications of spread spectrum technology to very small aperture terminal (VSAT) satellite communication networks are presented. Two spread spectrum multiple access systems which use a form of noncoherent M-ary FSK (MFSK) as the primary modulation are described and the throughput analyzed. The analysis considers such factors as satellite power constraints and adjacent satellite interference. Also considered is the effect of on-board processing on the multiple access efficiency and the feasibility of overlaying low data rate spread spectrum signals on existing satellite traffic as a form of frequency reuse is investigated. The use of chirp is examined for spread spectrum communications. In a chirp communication system, each data bit is converted into one or more up or down sweeps of frequency, which spread the RF energy across a broad range of frequencies. Several different forms of chirp communication systems are considered, and a multiple-chirp coded system is proposed for overlay service. The mutual interference problem is examined in detail and a performance analysis undertaken for the case of a chirp data channel overlaid on a video channel.

Optimal Resource Allocation for NOMA-TDMA Scheme with α-Fairness in Industrial Internet of Things.

PubMed

Sun, Yanjing; Guo, Yiyu; Li, Song; Wu, Dapeng; Wang, Bin

2018-05-15

In this paper, a joint non-orthogonal multiple access and time division multiple access (NOMA-TDMA) scheme is proposed in Industrial Internet of Things (IIoT), which allowed multiple sensors to transmit in the same time-frequency resource block using NOMA. The user scheduling, time slot allocation, and power control are jointly optimized in order to maximize the system α -fair utility under transmit power constraint and minimum rate constraint. The optimization problem is nonconvex because of the fractional objective function and the nonconvex constraints. To deal with the original problem, we firstly convert the objective function in the optimization problem into a difference of two convex functions (D.C.) form, and then propose a NOMA-TDMA-DC algorithm to exploit the global optimum. Numerical results show that the NOMA-TDMA scheme significantly outperforms the traditional orthogonal multiple access scheme in terms of both spectral efficiency and user fairness.

bioWeb3D: an online webGL 3D data visualisation tool

PubMed Central

2013-01-01

Background Data visualization is critical for interpreting biological data. However, in practice it can prove to be a bottleneck for non trained researchers; this is especially true for three dimensional (3D) data representation. Whilst existing software can provide all necessary functionalities to represent and manipulate biological 3D datasets, very few are easily accessible (browser based), cross platform and accessible to non-expert users. Results An online HTML5/WebGL based 3D visualisation tool has been developed to allow biologists to quickly and easily view interactive and customizable three dimensional representations of their data along with multiple layers of information. Using the WebGL library Three.js written in Javascript, bioWeb3D allows the simultaneous visualisation of multiple large datasets inputted via a simple JSON, XML or CSV file, which can be read and analysed locally thanks to HTML5 capabilities. Conclusions Using basic 3D representation techniques in a technologically innovative context, we provide a program that is not intended to compete with professional 3D representation software, but that instead enables a quick and intuitive representation of reasonably large 3D datasets. PMID:23758781

The design of an m-Health monitoring system based on a cloud computing platform

NASA Astrophysics Data System (ADS)

Xu, Boyi; Xu, Lida; Cai, Hongming; Jiang, Lihong; Luo, Yang; Gu, Yizhi

2017-01-01

Compared to traditional medical services provided within hospitals, m-Health monitoring systems (MHMSs) face more challenges in personalised health data processing. To achieve personalised and high-quality health monitoring by means of new technologies, such as mobile network and cloud computing, in this paper, a framework of an m-Health monitoring system based on a cloud computing platform (Cloud-MHMS) is designed to implement pervasive health monitoring. Furthermore, the modules of the framework, which are Cloud Storage and Multiple Tenants Access Control Layer, Healthcare Data Annotation Layer, and Healthcare Data Analysis Layer, are discussed. In the data storage layer, a multiple tenant access method is designed to protect patient privacy. In the data annotation layer, linked open data are adopted to augment health data interoperability semantically. In the data analysis layer, the process mining algorithm and similarity calculating method are implemented to support personalised treatment plan selection. These three modules cooperate to implement the core functions in the process of health monitoring, which are data storage, data processing, and data analysis. Finally, we study the application of our architecture in the monitoring of antimicrobial drug usage to demonstrate the usability of our method in personal healthcare analysis.

A Study of Dispersion Compensation of Polarization Multiplexing-Based OFDM-OCDMA for Radio-over-Fiber Transmissions

PubMed Central

Yen, Chih-Ta; Chen, Wen-Bin

2016-01-01

Chromatic dispersion from optical fiber is the most important problem that produces temporal skews and destroys the rectangular structure of code patterns in the spectra-amplitude-coding-based optical code-division multiple-access (SAC-OCDMA) system. Thus, the balance detection scheme does not work perfectly to cancel multiple access interference (MAI) and the system performance will be degraded. Orthogonal frequency-division multiplexing (OFDM) is the fastest developing technology in the academic and industrial fields of wireless transmission. In this study, the radio-over-fiber system is realized by integrating OFDM and OCDMA via polarization multiplexing scheme. The electronic dispersion compensation (EDC) equalizer element of OFDM integrated with the dispersion compensation fiber (DCF) is used in the proposed radio-over-fiber (RoF) system, which can efficiently suppress the chromatic dispersion influence in long-haul transmitted distance. A set of length differences for 10 km-long single-mode fiber (SMF) and 4 km-long DCF is to verify the compensation scheme by relative equalizer algorithms and constellation diagrams. In the simulation result, the proposed dispersion mechanism successfully compensates the dispersion from SMF and the system performance with dispersion equalizer is highly improved. PMID:27618042

Tactical resource allocation and elective patient admission planning in care processes.

PubMed

Hulshof, Peter J H; Boucherie, Richard J; Hans, Erwin W; Hurink, Johann L

2013-06-01

Tactical planning of resources in hospitals concerns elective patient admission planning and the intermediate term allocation of resource capacities. Its main objectives are to achieve equitable access for patients, to meet production targets/to serve the strategically agreed number of patients, and to use resources efficiently. This paper proposes a method to develop a tactical resource allocation and elective patient admission plan. These tactical plans allocate available resources to various care processes and determine the selection of patients to be served that are at a particular stage of their care process. Our method is developed in a Mixed Integer Linear Programming (MILP) framework and copes with multiple resources, multiple time periods and multiple patient groups with various uncertain treatment paths through the hospital, thereby integrating decision making for a chain of hospital resources. Computational results indicate that our method leads to a more equitable distribution of resources and provides control of patient access times, the number of patients served and the fraction of allocated resource capacity. Our approach is generic, as the base MILP and the solution approach allow for including various extensions to both the objective criteria and the constraints. Consequently, the proposed method is applicable in various settings of tactical hospital management.

Proceedings of the Fifth International Mobile Satellite Conference 1997

NASA Technical Reports Server (NTRS)

Jedrey, T. (Compiler); Rigley, J. (Compiler); Anderson, Louise (Editor)

1997-01-01

Satellite-based mobile communications systems provide voice and data communications to users over a vast geographic area. The users may communicate via mobile or hand-held terminals, which may also provide access to terrestrial communications services. While previous International Mobile Satellite Conferences have concentrated on technical advances and the increasing worldwide commercial activities, this conference focuses on the next generation of mobile satellite services. The approximately 80 papers included here cover sessions in the following areas: networking and protocols; code division multiple access technologies; demand, economics and technology issues; current and planned systems; propagation; terminal technology; modulation and coding advances; spacecraft technology; advanced systems; and applications and experiments.

Quantum Optimal Multiple Assignment Scheme for Realizing General Access Structure of Secret Sharing

NASA Astrophysics Data System (ADS)

Matsumoto, Ryutaroh

The multiple assignment scheme is to assign one or more shares to single participant so that any kind of access structure can be realized by classical secret sharing schemes. We propose its quantum version including ramp secret sharing schemes. Then we propose an integer optimization approach to minimize the average share size.

Performance enhancement of optical code-division multiple-access systems using transposed modified Walsh code

NASA Astrophysics Data System (ADS)

Sikder, Somali; Ghosh, Shila

2018-02-01

This paper presents the construction of unipolar transposed modified Walsh code (TMWC) and analysis of its performance in optical code-division multiple-access (OCDMA) systems. Specifically, the signal-to-noise ratio, bit error rate (BER), cardinality, and spectral efficiency were investigated. The theoretical analysis demonstrated that the wavelength-hopping time-spreading system using TMWC was robust against multiple-access interference and more spectrally efficient than systems using other existing OCDMA codes. In particular, the spectral efficiency was calculated to be 1.0370 when TMWC of weight 3 was employed. The BER and eye pattern for the designed TMWC were also successfully obtained using OptiSystem simulation software. The results indicate that the proposed code design is promising for enhancing network capacity.

Understanding and improving access to prompt and effective malaria treatment and care in rural Tanzania: the ACCESS Programme.

PubMed

Hetzel, Manuel W; Iteba, Nelly; Makemba, Ahmed; Mshana, Christopher; Lengeler, Christian; Obrist, Brigit; Schulze, Alexander; Nathan, Rose; Dillip, Angel; Alba, Sandra; Mayumana, Iddy; Khatib, Rashid A; Njau, Joseph D; Mshinda, Hassan

2007-06-29

Prompt access to effective treatment is central in the fight against malaria. However, a variety of interlinked factors at household and health system level influence access to timely and appropriate treatment and care. Furthermore, access may be influenced by global and national health policies. As a consequence, many malaria episodes in highly endemic countries are not treated appropriately. The ACCESS Programme aims at understanding and improving access to prompt and effective malaria treatment and care in a rural Tanzanian setting. The programme's strategy is based on a set of integrated interventions, including social marketing for improved care seeking at community level as well as strengthening of quality of care at health facilities. This is complemented by a project that aims to improve the performance of drug stores. The interventions are accompanied by a comprehensive set of monitoring and evaluation activities measuring the programme's performance and (health) impact. Baseline data demonstrated heterogeneity in the availability of malaria treatment, unavailability of medicines and treatment providers in certain areas as well as quality problems with regard to drugs and services. The ACCESS Programme is a combination of multiple complementary interventions with a strong evaluation component. With this approach, ACCESS aims to contribute to the development of a more comprehensive access framework and to inform and support public health professionals and policy-makers in the delivery of improved health services.

Q.U.E.S.T. An Interactive Earth Science Study Tool: Connecting Real Students to Digital Libraries

NASA Astrophysics Data System (ADS)

Moore, A.; Danowski, D.; Brindisi, C.; Sandvol, C.; Seber, D.

2001-05-01

Quick Use Earth Study Tool (QUEST) is an experimental educational interface to the Cornell University's Geoscience Information System (http://atlas.geo.cornell.edu). The information system currently includes more than 100 geographic, geologic, and geophysical data sets along with World Wide Web based interactive mapping tools for data display and analysis. The system is GIS based and accessible via any web browser that support Java applets. QUEST is the companion module that has been developed to assist educators who wish to use these data to their fullest potential, providing tutorials, sample exercises, and suggested projects. Clearly, students learn best when they engage in the practice of science. One means to accomplish this is to have students access primary scientific data. Our experience suggests that a structured exploration of original data sets enhances student learning. For this reason we have selected a subset of Cornell's available geoscience data, and have designed a series of activities that allow students to explore dynamic Earth processes. Currently, these data include the ISC seismicity catalog, volcanism data from the Smithsonian Institution, and digital topography from the USGS and NOAA. The QUEST interface allows students to query the data sets based on a variety of criteria (e.g., earthquakes can be sorted by date, magnitude, depth, and location), or perform computations on data (e.g., sea level can be interactively mapped at any elevation on the DEM). Because the system is GIS-based, multiple data sets can be displayed simultaneously in order for users to examine the spatial relationships between geological features. Users can zoom in to regions of interest, and a map history window keeps track of student work so that comparisons are easily made. QUEST is accompanied by a Teacher's Manual to assist teachers in extracting the most information from the available data and tools. Through these efforts we hope to provide teachers and students with access to a wide variety of data applicable to problems in Earth science, along with the ability to easily display and analyze multiple data types--thus providing all users with access to state-of-the-art information.

Research on Heterogeneous Data Exchange based on XML

NASA Astrophysics Data System (ADS)

Li, Huanqin; Liu, Jinfeng

Integration of multiple data sources is becoming increasingly important for enterprises that cooperate closely with their partners for e-commerce. OLAP enables analysts and decision makers fast access to various materialized views from data warehouses. However, many corporations have internal business applications deployed on different platforms. This paper introduces a model for heterogeneous data exchange based on XML. The system can exchange and share the data among the different sources. The method used to realize the heterogeneous data exchange is given in this paper.

Integration between terrestrial-based and satellite-based land mobile communications systems

NASA Technical Reports Server (NTRS)

Arcidiancono, Antonio

1990-01-01

A survey is given of several approaches to improving the performance and marketability of mobile satellite systems (MSS). The provision of voice/data services in the future regional European Land Mobile Satellite System (LMSS), network integration between the Digital Cellular Mobile System (GSM) and LMSS, the identification of critical areas for the implementation of integrated GSM/LMSS areas, space segment scenarios, LMSS for digital trunked private mobile radio (PMR) services, and code division multiple access (CDMA) techniques for a terrestrial/satellite system are covered.

System and method for integrating hazard-based decision making tools and processes

DOEpatents

Hodgin, C Reed [Westminster, CO

2012-03-20

A system and method for inputting, analyzing, and disseminating information necessary for identified decision-makers to respond to emergency situations. This system and method provides consistency and integration among multiple groups, and may be used for both initial consequence-based decisions and follow-on consequence-based decisions. The system and method in a preferred embodiment also provides tools for accessing and manipulating information that are appropriate for each decision-maker, in order to achieve more reasoned and timely consequence-based decisions. The invention includes processes for designing and implementing a system or method for responding to emergency situations.

Data on the relationships between financing strategies, entrepreneurial competencies and business growth of technology-based SMEs in Nigeria.

PubMed

Ibidunni, Ayodotun Stephen; Kehinde, Oladele Joseph; Ibidunni, Oyebisi Mary; Olokundun, Maxwell Ayodele; Olubusayo, Falola Hezekiah; Salau, Odunayo Paul; Borishade, Taiye Tairat; Fred, Peter

2018-06-01

The article presents data on the relationship between financing strategies, entrepreneurial competencies and business growth of technology-based SMEs in Nigeria. Copies of structured questionnaire were administered to 233 SME owners and financial managers. Using descriptive and standard multiple regression statistical analysis, the data revealed that venture capital and business donations significantly influences profit growth of technology-based SMEs. Moreover, the data revealed that technology-`based firms can enhance their access to financing through capacity building in entrepreneurial competencies, such as acquiring the right skills and attitude.

Performance optimization of spectral amplitude coding OCDMA system using new enhanced multi diagonal code

NASA Astrophysics Data System (ADS)

Imtiaz, Waqas A.; Ilyas, M.; Khan, Yousaf

2016-11-01

This paper propose a new code to optimize the performance of spectral amplitude coding-optical code division multiple access (SAC-OCDMA) system. The unique two-matrix structure of the proposed enhanced multi diagonal (EMD) code and effective correlation properties, between intended and interfering subscribers, significantly elevates the performance of SAC-OCDMA system by negating multiple access interference (MAI) and associated phase induce intensity noise (PIIN). Performance of SAC-OCDMA system based on the proposed code is thoroughly analyzed for two detection techniques through analytic and simulation analysis by referring to bit error rate (BER), signal to noise ratio (SNR) and eye patterns at the receiving end. It is shown that EMD code while using SDD technique provides high transmission capacity, reduces the receiver complexity, and provides better performance as compared to complementary subtraction detection (CSD) technique. Furthermore, analysis shows that, for a minimum acceptable BER of 10-9 , the proposed system supports 64 subscribers at data rates of up to 2 Gbps for both up-down link transmission.

An integrated and accessible sample data library for Mars sample return science

NASA Astrophysics Data System (ADS)

Tuite, M. L., Jr.; Williford, K. H.

2015-12-01

Over the course of the next decade or more, many thousands of geological samples will be collected and analyzed in a variety of ways by researchers at the Jet Propulsion Laboratory (California Institute of Technology) in order to facilitate discovery and contextualize observations made of Mars rocks both in situ and here on Earth if samples are eventually returned. Integration of data from multiple analyses of samples including petrography, thin section and SEM imaging, isotope and organic geochemistry, XRF, XRD, and Raman spectrometry is a challenge and a potential obstacle to discoveries that require supporting lines of evidence. We report the development of a web-accessible repository, the Sample Data Library (SDL) for the sample-based data that are generated by the laboratories and instruments that comprise JPL's Center for Analysis of Returned Samples (CARS) in order to facilitate collaborative interpretation of potential biosignatures in Mars-analog geological samples. The SDL is constructed using low-cost, open-standards-based Amazon Web Services (AWS), including web-accessible storage, relational data base services, and a virtual web server. The data structure is sample-centered with a shared registry for assigning unique identifiers to all samples including International Geo-Sample Numbers. Both raw and derived data produced by instruments and post-processing workflows are automatically uploaded to online storage and linked via the unique identifiers. Through the web interface, users are able to find all the analyses associated with a single sample or search across features shared by multiple samples, sample localities, and analysis types. Planned features include more sophisticated search and analytical interfaces as well as data discoverability through NSF's EarthCube program.

Allocation and management issues in multiple-transaction open access transmission networks

NASA Astrophysics Data System (ADS)

Tao, Shu

This thesis focuses on some key issues related to allocation and management by the independent grid operator (IGO) of unbundled services in multiple-transaction open access transmission networks. The three unbundled services addressed in the thesis are transmission real power losses, reactive power support requirements from generation sources, and transmission congestion management. We develop the general framework that explicitly represents multiple transactions undertaken simultaneously in the transmission grid. This framework serves as the basis for formulating various problems treated in the thesis. We use this comprehensive framework to develop a physical-flow-based mechanism to allocate the total transmission losses to each transaction using the system. An important property of the allocation scheme is its capability to effectively deal with counter flows that result in the presence of specific transactions. Using the loss allocation results as the basis, we construct the equivalent loss compensation concept and apply it to develop flexible and effective procedures for compensating losses in multiple-transaction networks. We present a new physical-flow-based mechanism for allocating the reactive power support requirements provided by generators in multiple-transaction networks. The allocatable reactive support requirements are formulated as the sum of two specific components---the voltage magnitude variation component and the voltage angle variation component. The formulation utilizes the multiple-transaction framework and makes use of certain simplifying approximations. The formulation leads to a natural allocation as a function of the amount of each transaction. The physical interpretation of each allocation as a sensitivity of the reactive output of a generator is discussed. We propose a congestion management allocation scheme for multiple-transaction networks. The proposed scheme determines the allocation of congestion among the transactions on a physical-flow basis. It also proposes a congestion relief scheme that removes the congestion attributed to each transaction on the network in a least-cost manner to the IGO and determines the appropriate transmission charges to each transaction for its transmission usage. The thesis provides a compendium of problems that are natural extensions of the research results reported here and appear to be good candidates for future work.

Scalable Lunar Surface Networks and Adaptive Orbit Access

NASA Technical Reports Server (NTRS)

Wang, Xudong

2015-01-01

Teranovi Technologies, Inc., has developed innovative network architecture, protocols, and algorithms for both lunar surface and orbit access networks. A key component of the overall architecture is a medium access control (MAC) protocol that includes a novel mechanism of overlaying time division multiple access (TDMA) and carrier sense multiple access with collision avoidance (CSMA/CA), ensuring scalable throughput and quality of service. The new MAC protocol is compatible with legacy Institute of Electrical and Electronics Engineers (IEEE) 802.11 networks. Advanced features include efficiency power management, adaptive channel width adjustment, and error control capability. A hybrid routing protocol combines the advantages of ad hoc on-demand distance vector (AODV) routing and disruption/delay-tolerant network (DTN) routing. Performance is significantly better than AODV or DTN and will be particularly effective for wireless networks with intermittent links, such as lunar and planetary surface networks and orbit access networks.

Satellite Remote Sensing of Harmful Algal Blooms (HABs) and a Potential Synthesized Framework

PubMed Central

Shen, Li; Xu, Huiping; Guo, Xulin

2012-01-01

Harmful algal blooms (HABs) are severe ecological disasters threatening aquatic systems throughout the World, which necessitate scientific efforts in detecting and monitoring them. Compared with traditional in situ point observations, satellite remote sensing is considered as a promising technique for studying HABs due to its advantages of large-scale, real-time, and long-term monitoring. The present review summarizes the suitability of current satellite data sources and different algorithms for detecting HABs. It also discusses the spatial scale issue of HABs. Based on the major problems identified from previous literature, including the unsystematic understanding of HABs, the insufficient incorporation of satellite remote sensing, and a lack of multiple oceanographic explanations of the mechanisms causing HABs, this review also attempts to provide a comprehensive understanding of the complicated mechanism of HABs impacted by multiple oceanographic factors. A potential synthesized framework can be established by combining multiple accessible satellite remote sensing approaches including visual interpretation, spectra analysis, parameters retrieval and spatial-temporal pattern analysis. This framework aims to lead to a systematic and comprehensive monitoring of HABs based on satellite remote sensing from multiple oceanographic perspectives. PMID:22969372

Worst-Case Energy Efficiency Maximization in a 5G Massive MIMO-NOMA System.

PubMed

Chinnadurai, Sunil; Selvaprabhu, Poongundran; Jeong, Yongchae; Jiang, Xueqin; Lee, Moon Ho

2017-09-18

In this paper, we examine the robust beamforming design to tackle the energy efficiency (EE) maximization problem in a 5G massive multiple-input multiple-output (MIMO)-non-orthogonal multiple access (NOMA) downlink system with imperfect channel state information (CSI) at the base station. A novel joint user pairing and dynamic power allocation (JUPDPA) algorithm is proposed to minimize the inter user interference and also to enhance the fairness between the users. This work assumes imperfect CSI by adding uncertainties to channel matrices with worst-case model, i.e., ellipsoidal uncertainty model (EUM). A fractional non-convex optimization problem is formulated to maximize the EE subject to the transmit power constraints and the minimum rate requirement for the cell edge user. The designed problem is difficult to solve due to its nonlinear fractional objective function. We firstly employ the properties of fractional programming to transform the non-convex problem into its equivalent parametric form. Then, an efficient iterative algorithm is proposed established on the constrained concave-convex procedure (CCCP) that solves and achieves convergence to a stationary point of the above problem. Finally, Dinkelbach's algorithm is employed to determine the maximum energy efficiency. Comprehensive numerical results illustrate that the proposed scheme attains higher worst-case energy efficiency as compared with the existing NOMA schemes and the conventional orthogonal multiple access (OMA) scheme.

Worst-Case Energy Efficiency Maximization in a 5G Massive MIMO-NOMA System

PubMed Central

Jeong, Yongchae; Jiang, Xueqin; Lee, Moon Ho

2017-01-01

In this paper, we examine the robust beamforming design to tackle the energy efficiency (EE) maximization problem in a 5G massive multiple-input multiple-output (MIMO)-non-orthogonal multiple access (NOMA) downlink system with imperfect channel state information (CSI) at the base station. A novel joint user pairing and dynamic power allocation (JUPDPA) algorithm is proposed to minimize the inter user interference and also to enhance the fairness between the users. This work assumes imperfect CSI by adding uncertainties to channel matrices with worst-case model, i.e., ellipsoidal uncertainty model (EUM). A fractional non-convex optimization problem is formulated to maximize the EE subject to the transmit power constraints and the minimum rate requirement for the cell edge user. The designed problem is difficult to solve due to its nonlinear fractional objective function. We firstly employ the properties of fractional programming to transform the non-convex problem into its equivalent parametric form. Then, an efficient iterative algorithm is proposed established on the constrained concave-convex procedure (CCCP) that solves and achieves convergence to a stationary point of the above problem. Finally, Dinkelbach’s algorithm is employed to determine the maximum energy efficiency. Comprehensive numerical results illustrate that the proposed scheme attains higher worst-case energy efficiency as compared with the existing NOMA schemes and the conventional orthogonal multiple access (OMA) scheme. PMID:28927019

Storage and distribution of pathology digital images using integrated web-based viewing systems.

PubMed

Marchevsky, Alberto M; Dulbandzhyan, Ronda; Seely, Kevin; Carey, Steve; Duncan, Raymond G

2002-05-01

Health care providers have expressed increasing interest in incorporating digital images of gross pathology specimens and photomicrographs in routine pathology reports. To describe the multiple technical and logistical challenges involved in the integration of the various components needed for the development of a system for integrated Web-based viewing, storage, and distribution of digital images in a large health system. An Oracle version 8.1.6 database was developed to store, index, and deploy pathology digital photographs via our Intranet. The database allows for retrieval of images by patient demographics or by SNOMED code information. The Intranet of a large health system accessible from multiple computers located within the medical center and at distant private physician offices. The images can be viewed using any of the workstations of the health system that have authorized access to our Intranet, using a standard browser or a browser configured with an external viewer or inexpensive plug-in software, such as Prizm 2.0. The images can be printed on paper or transferred to film using a digital film recorder. Digital images can also be displayed at pathology conferences by using wireless local area network (LAN) and secure remote technologies. The standardization of technologies and the adoption of a Web interface for all our computer systems allows us to distribute digital images from a pathology database to a potentially large group of users distributed in multiple locations throughout a large medical center.

Link Scheduling Algorithm with Interference Prediction for Multiple Mobile WBANs

PubMed Central

Le, Thien T. T.

2017-01-01

As wireless body area networks (WBANs) become a key element in electronic healthcare (e-healthcare) systems, the coexistence of multiple mobile WBANs is becoming an issue. The network performance is negatively affected by the unpredictable movement of the human body. In such an environment, inter-WBAN interference can be caused by the overlapping transmission range of nearby WBANs. We propose a link scheduling algorithm with interference prediction (LSIP) for multiple mobile WBANs, which allows multiple mobile WBANs to transmit at the same time without causing inter-WBAN interference. In the LSIP, a superframe includes the contention access phase using carrier sense multiple access with collision avoidance (CSMA/CA) and the scheduled phase using time division multiple access (TDMA) for non-interfering nodes and interfering nodes, respectively. For interference prediction, we define a parameter called interference duration as the duration during which disparate WBANs interfere with each other. The Bayesian model is used to estimate and classify the interference using a signal to interference plus noise ratio (SINR) and the number of neighboring WBANs. The simulation results show that the proposed LSIP algorithm improves the packet delivery ratio and throughput significantly with acceptable delay. PMID:28956827

Advancements in Data Access at the IRIS Data Management Center to Broaden Data Use

NASA Astrophysics Data System (ADS)

Benson, R. B.; Trabant, C. M.; Ahern, T. K.

2013-12-01

The IRIS Data Management Center (DMC) has been serving digital seismic data for more than 20 years and has offered a variety of access mechanisms that have stood the test of time. However, beginning in 2010, and in response to multiple needs being requested from the IRIS DMC, we have developed web service interfaces to access our primary data repository. These new interfaces have rapidly grown in popularity. In 2013, the third full year of their operation, these services were responsible for half of all the data shipped from the DMC. In the same time period, the amount of data shipped from the other data access mechanisms has also increased. This non-linear growth of data shipments reflects the increased data usage by the research community. We believe that our new web service interfaces are well suited to fit future data access needs and signify a significant evolution in integrating different scientific data sets. Based on standardized web technologies, support for writing access software is ubiquitous. As fundamentally programmatic interfaces, the services are well suited for integration into data processing systems, in particular large-scale data processing systems. Their programmatic nature also makes then well suited for use with brokering systems where, for example, data from multiple disciplines can be integrated. In addition to providing access to raw data, the DMC created web services that apply simple, on-the-fly processing and format conversion. Processing the data (e.g. converting to Earth units) and formatting the result into something generally usable (e.g. ASCII) removes important barriers for users working in other disciplines. The end result is that we are shipping a much larger amount of data in a manner more directly usable by users. Many of these principles will be applied to the DMC's future work in the NSF's EarthCube Web Service Building Blocks project.

Persons with Multiple Disabilities Use Forehead and Smile Responses to Access or Choose among Technology-Aided Stimulation Events

ERIC Educational Resources Information Center

Lancioni, Giulio E.; Singh, Nirbhay N.; O'Reilly, Mark F.; Sigafoos, Jeff; Alberti, Gloria; Bellini, Domencio; Oliva, Doretta; Boccasini, Adele; La Martire, Maria L.; Signorino, Mario

2013-01-01

A variety of technology-aided programs have been developed to help persons with congenital or acquired multiple disabilities access preferred stimuli or choose among stimulus options. The application of those programs may pose problems when the participants have very limited behavior repertoires and are unable to use conventional responses and…

Multiple Access Interference Reduction Using Received Response Code Sequence for DS-CDMA UWB System

NASA Astrophysics Data System (ADS)

Toh, Keat Beng; Tachikawa, Shin'ichi

This paper proposes a combination of novel Received Response (RR) sequence at the transmitter and a Matched Filter-RAKE (MF-RAKE) combining scheme receiver system for the Direct Sequence-Code Division Multiple Access Ultra Wideband (DS-CDMA UWB) multipath channel model. This paper also demonstrates the effectiveness of the RR sequence in Multiple Access Interference (MAI) reduction for the DS-CDMA UWB system. It suggests that by using conventional binary code sequence such as the M sequence or the Gold sequence, there is a possibility of generating extra MAI in the UWB system. Therefore, it is quite difficult to collect the energy efficiently although the RAKE reception method is applied at the receiver. The main purpose of the proposed system is to overcome the performance degradation for UWB transmission due to the occurrence of MAI during multiple accessing in the DS-CDMA UWB system. The proposed system improves the system performance by improving the RAKE reception performance using the RR sequence which can reduce the MAI effect significantly. Simulation results verify that significant improvement can be obtained by the proposed system in the UWB multipath channel models.

WISE-MD usage among millennial medical students.

PubMed

Phitayakorn, Roy; Nick, Michael W; Alseidi, Adnan; Lind, David Scott; Sudan, Ranjan; Isenberg, Gerald; Capella, Jeannette; Hopkins, Mary A; Petrusa, Emil R

2015-01-01

E-learning is increasingly common in undergraduate medical education. Internet-based multimedia materials should be designed with millennial learner utilization preferences in mind for maximal impact. Medical students used all 20 Web Initiative for Surgical Education of Medical Doctors modules from July 1, 2013 to October 1, 2013. Data were analyzed for topic frequency, time and week day, and access to questions. Three thousand five hundred eighty-seven students completed 35,848 modules. Students accessed modules for average of 51 minutes. Most frequent use occurred on Sunday (23.1%), Saturday (15.4%), and Monday (14.3%). Friday had the least use (8.2%). A predominance of students accessed the modules between 7 and 10 PM (34.4%). About 80.4% of students accessed questions for at least one module. They completed an average of 40 ± 30 of the questions. Only 827 students (2.3%) repeated the questions. Web Initiative for Surgical Education of Medical Doctors has peak usage during the weekend and evenings. Most frequently used modules reflect core surgical problems. Multiple factors influence the manner module questions are accessed. Copyright © 2015 Elsevier Inc. All rights reserved.

Implementation of a Cross-Layer Sensing Medium-Access Control Scheme.

PubMed

Su, Yishan; Fu, Xiaomei; Han, Guangyao; Xu, Naishen; Jin, Zhigang

2017-04-10

In this paper, compressed sensing (CS) theory is utilized in a medium-access control (MAC) scheme for wireless sensor networks (WSNs). We propose a new, cross-layer compressed sensing medium-access control (CL CS-MAC) scheme, combining the physical layer and data link layer, where the wireless transmission in physical layer is considered as a compress process of requested packets in a data link layer according to compressed sensing (CS) theory. We first introduced using compressive complex requests to identify the exact active sensor nodes, which makes the scheme more efficient. Moreover, because the reconstruction process is executed in a complex field of a physical layer, where no bit and frame synchronizations are needed, the asynchronous and random requests scheme can be implemented without synchronization payload. We set up a testbed based on software-defined radio (SDR) to implement the proposed CL CS-MAC scheme practically and to demonstrate the validation. For large-scale WSNs, the simulation results show that the proposed CL CS-MAC scheme provides higher throughput and robustness than the carrier sense multiple access (CSMA) and compressed sensing medium-access control (CS-MAC) schemes.

Exploring the Viability of School-Based Support for Vulnerable Children: A Case Study of Two Township Schools in Johannesburg. CREATE Pathways to Access. Research Monograph No. 46

ERIC Educational Resources Information Center

Williams, Samantha E.

2010-01-01

The South African Department of Education is working with multiple non-governmental organisations (NGOs) to transform schools into "caring schools" that emphasise: health promotion, safety, care for orphans and vulnerable children, quality education, community engagement and respect for rights and equality. Using a qualitative case study…

An Examination of One-to-One Computing in the Middle School: Does Increased Access Bring about Increased Student Engagement?

ERIC Educational Resources Information Center

Donovan, Loretta; Green, Tim; Hartley, Kendall

2010-01-01

This study explores configurations of laptop use in a one-to-one environment. Guided by methodologies of the Concerns-Based Adoption Model of change, an Innovation Configuration Map (description of the multiple ways an innovation is implemented) of a 1:1 laptop program at a middle school was developed and analyzed. Three distinct configurations…

TMS communications hardware. Volume 2: Bus interface unit

NASA Technical Reports Server (NTRS)

Brown, J. S.; Hopkins, G. T.

1979-01-01

A prototype coaxial cable bus communication system used in the Trend Monitoring System to interconnect intelligent graphics terminals to a host minicomputer is described. The terminals and host are connected to the bus through a microprocessor-based RF modem termed a Bus Interface Unit (BIU). The BIU hardware and the Carrier Sense Multiple Access Listen-While-Talk protocol used on the network are described.

So you think you've designed an effective recruitment protocol?

PubMed

Green, Cara; Vandall-Walker, Virginia

2017-03-22

Background Recruiting acutely ill patients to participate in research can be challenging. This paper outlines the difficulties the first author encountered in a study and the steps she took to overcome problems with research ethics, gain access to participants and implement a recruitment protocol in multiple hospitals. It also compares these steps with literature related to recruitment. Aim To inform and inspire neophyte researchers about the need for planning and resilience when dealing with recruitment challenges in multiple hospitals. Discussion The multiple enablers and barriers to the successful implementation of a hospital-based study recruitment protocol are explored based on a neophyte researcher's optimistic assumptions about this stage of the study. Conclusions Perseverance, adequately planning for contingencies, and accepting the barriers and challenges to recruitment are essential for completing one's research study and ensuring fulfilment as a researcher. Implications for practice Healthcare students carrying out research require adequate knowledge about conducting hospital-based, patient research to inform their recruitment plan. Maximising control over recruitment, allowing for adequate time to conduct data collection, and maintaining a good work ethic will help to ensure success.

A Review on Spectral Amplitude Coding Optical Code Division Multiple Access

NASA Astrophysics Data System (ADS)

Kaur, Navpreet; Goyal, Rakesh; Rani, Monika

2017-06-01

This manuscript deals with analysis of Spectral Amplitude Coding Optical Code Division Multiple Access (SACOCDMA) system. The major noise source in optical CDMA is co-channel interference from other users known as multiple access interference (MAI). The system performance in terms of bit error rate (BER) degrades as a result of increased MAI. It is perceived that number of users and type of codes used for optical system directly decide the performance of system. MAI can be restricted by efficient designing of optical codes and implementing them with unique architecture to accommodate more number of users. Hence, it is a necessity to design a technique like spectral direct detection (SDD) technique with modified double weight code, which can provide better cardinality and good correlation property.

Can hydro-economic river basin models simulate water shadow prices under asymmetric access?

PubMed

Kuhn, A; Britz, W

2012-01-01

Hydro-economic river basin models (HERBM) based on mathematical programming are conventionally formulated as explicit 'aggregate optimization' problems with a single, aggregate objective function. Often unintended, this format implicitly assumes that decisions on water allocation are made via central planning or functioning markets such as to maximize social welfare. In the absence of perfect water markets, however, individually optimal decisions by water users will differ from the social optimum. Classical aggregate HERBMs cannot simulate that situation and thus might be unable to describe existing institutions governing access to water and might produce biased results for alternative ones. We propose a new solution format for HERBMs, based on the format of the mixed complementarity problem (MCP), where modified shadow price relations express spatial externalities resulting from asymmetric access to water use. This new problem format, as opposed to commonly used linear (LP) or non-linear programming (NLP) approaches, enables the simultaneous simulation of numerous 'independent optimization' decisions by multiple water users while maintaining physical interdependences based on water use and flow in the river basin. We show that the alternative problem format allows the formulation HERBMs that yield more realistic results when comparing different water management institutions.

Looking to the future of new media in health marketing: deriving propositions based on traditional theories.

PubMed

Della, Lindsay J; Eroglu, Dogan; Bernhardt, Jay M; Edgerton, Erin; Nall, Janice

2008-01-01

Market trend data show that the media marketplace continues to rapidly evolve. Recent research shows that substantial portions of the U.S. media population are "new media" users. Today, more than ever before, media consumers are exposed to multiple media at the same point in time, encouraged to participate in media content generation, and challenged to learn, access, and use the new media that are continually entering the market. These media trends have strong implications for how consumers of health information access, process, and retain health-related knowledge. In this article we review traditional information processing models and theories of interpersonal and mass media access and consumption. We make several theory-based propositions for how traditional information processing and media consumption concepts will function as new media usage continues to increase. These propositions are supported by new media usage data from the Centers for Disease Control and Prevention's entry into the new media market (e.g., podcasting, virtual events, blogging, and webinars). Based on these propositions, we conclude by presenting both opportunities and challenges that public health communicators and marketers will face in the future.

Adjacency Matrix-Based Transmit Power Allocation Strategies in Wireless Sensor Networks

PubMed Central

Consolini, Luca; Medagliani, Paolo; Ferrari, Gianluigi

2009-01-01

In this paper, we present an innovative transmit power control scheme, based on optimization theory, for wireless sensor networks (WSNs) which use carrier sense multiple access (CSMA) with collision avoidance (CA) as medium access control (MAC) protocol. In particular, we focus on schemes where several remote nodes send data directly to a common access point (AP). Under the assumption of finite overall network transmit power and low traffic load, we derive the optimal transmit power allocation strategy that minimizes the packet error rate (PER) at the AP. This approach is based on modeling the CSMA/CA MAC protocol through a finite state machine and takes into account the network adjacency matrix, depending on the transmit power distribution and determining the network connectivity. It will be then shown that the transmit power allocation problem reduces to a convex constrained minimization problem. Our results show that, under the assumption of low traffic load, the power allocation strategy, which guarantees minimal delay, requires the maximization of network connectivity, which can be equivalently interpreted as the maximization of the number of non-zero entries of the adjacency matrix. The obtained theoretical results are confirmed by simulations for unslotted Zigbee WSNs. PMID:22346705

A knowledge base of the chemical compounds of intermediary metabolism.

PubMed

Karp, P D

1992-08-01

This paper describes a publicly available knowledge base of the chemical compounds involved in intermediary metabolism. We consider the motivations for constructing a knowledge base of metabolic compounds, the methodology by which it was constructed, and the information that it currently contains. Currently the knowledge base describes 981 compounds, listing for each: synonyms for its name, a systematic name, CAS registry number, chemical formula, molecular weight, chemical structure and two-dimensional display coordinates for the structure. The Compound Knowledge Base (CompoundKB) illustrates several methodological principles that should guide the development of biological knowledge bases. I argue that biological datasets should be made available in multiple representations to increase their accessibility to end users, and I present multiple representations of the CompoundKB (knowledge base, relational data base and ASN. 1 representations). I also analyze the general characteristics of these representations to provide an understanding of their relative advantages and disadvantages. Another principle is that the error rate of biological data bases should be estimated and documented-this analysis is performed for the CompoundKB.

Multiple Intimate Partner Violence Experiences: Knowledge, Access, Utilization and Barriers to Utilization of Resources by Women of the African Diaspora

PubMed Central

Sabri, Bushra; Huerta, Julia; Alexander, Kamila A.; St.Vil, Noelle M.; Campbell, Jacquelyn C.; Callwood, Gloria B.

2016-01-01

Objective This study examined knowledge, access, utilization, and barriers to use of resources among Black women exposed to multiple types of intimate partner violence in Baltimore, Maryland and the U.S. Virgin Islands (USVI). Methods We analyzed quantitative survey data collected by 163 women recruited from primary care, prenatal or family planning clinics in Baltimore and the USVI. In addition we analyzed qualitative data from in-depth interviews with 11 women. Quantitative data were analyzed using descriptive statistics and qualitative data were analyzed using thematic analysis. Results A substantial proportion of Black women with multiple types of violence experiences lacked knowledge of, did not have access to, and did not use resources. Barriers to resource use were identified at the individual, relationship, and community levels. Conclusion There is need for programs to develop awareness, promote access and utilization of resources, and eliminate barriers to resource use among abused Black women. PMID:26548679

Invisible Light: a global infotainment community based on augmented reality technologies

NASA Astrophysics Data System (ADS)

Israel, Kai; Wozniak, Peter; Vauderwange, Oliver; Curticapean, Dan

2015-10-01

Theoretical details about optics and photonics are not common knowledge nowadays. Physicists are keen to scientifically explain `light,' which has a huge impact on our lives. It is necessary to examine it from multiple perspectives and to make the knowledge accessible to the public in an interdisciplinary, scientifically well-grounded and appealing medial way. To allow an information exchange on a global scale, our project "Invisible Light" establishes a worldwide accessible platform. Its contents will not be created by a single instance, but user-generated, with the help of the global community. The article describes the infotainment portal "Invisible Light," which stores scientific articles about light and photonics and makes them accessible worldwide. All articles are tagged with geo-coordinates, so they can be clearly identified and localized. A smartphone application is used for visualization, transmitting the information to users in real time by means of an augmented reality application. Scientific information is made accessible for a broad audience and in an attractive manner.

A JEE RESTful service to access Conditions Data in ATLAS

NASA Astrophysics Data System (ADS)

Formica, Andrea; Gallas, E. J.

2015-12-01

Usage of condition data in ATLAS is extensive for offline reconstruction and analysis (e.g. alignment, calibration, data quality). The system is based on the LCG Conditions Database infrastructure, with read and write access via an ad hoc C++ API (COOL), a system which was developed before Run 1 data taking began. The infrastructure dictates that the data is organized into separate schemas (assigned to subsystems/groups storing distinct and independent sets of conditions), making it difficult to access information from several schemas at the same time. We have thus created PL/SQL functions containing queries to provide content extraction at multi-schema level. The PL/SQL API has been exposed to external clients by means of a Java application providing DB access via REST services, deployed inside an application server (JBoss WildFly). The services allow navigation over multiple schemas via simple URLs. The data can be retrieved either in XML or JSON formats, via simple clients (like curl or Web browsers).

Remote visual analysis of large turbulence databases at multiple scales

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pulido, Jesus; Livescu, Daniel; Kanov, Kalin

The remote analysis and visualization of raw large turbulence datasets is challenging. Current accurate direct numerical simulations (DNS) of turbulent flows generate datasets with billions of points per time-step and several thousand time-steps per simulation. Until recently, the analysis and visualization of such datasets was restricted to scientists with access to large supercomputers. The public Johns Hopkins Turbulence database simplifies access to multi-terabyte turbulence datasets and facilitates the computation of statistics and extraction of features through the use of commodity hardware. In this paper, we present a framework designed around wavelet-based compression for high-speed visualization of large datasets and methodsmore » supporting multi-resolution analysis of turbulence. By integrating common technologies, this framework enables remote access to tools available on supercomputers and over 230 terabytes of DNS data over the Web. Finally, the database toolset is expanded by providing access to exploratory data analysis tools, such as wavelet decomposition capabilities and coherent feature extraction.« less

Remote visual analysis of large turbulence databases at multiple scales

DOE PAGES

Pulido, Jesus; Livescu, Daniel; Kanov, Kalin; ...

2018-06-15

The remote analysis and visualization of raw large turbulence datasets is challenging. Current accurate direct numerical simulations (DNS) of turbulent flows generate datasets with billions of points per time-step and several thousand time-steps per simulation. Until recently, the analysis and visualization of such datasets was restricted to scientists with access to large supercomputers. The public Johns Hopkins Turbulence database simplifies access to multi-terabyte turbulence datasets and facilitates the computation of statistics and extraction of features through the use of commodity hardware. In this paper, we present a framework designed around wavelet-based compression for high-speed visualization of large datasets and methodsmore » supporting multi-resolution analysis of turbulence. By integrating common technologies, this framework enables remote access to tools available on supercomputers and over 230 terabytes of DNS data over the Web. Finally, the database toolset is expanded by providing access to exploratory data analysis tools, such as wavelet decomposition capabilities and coherent feature extraction.« less

Pragmatic Metadata Management for Integration into Multiple Spatial Data Infrastructure Systems and Platforms

NASA Astrophysics Data System (ADS)

Benedict, K. K.; Scott, S.

2013-12-01

While there has been a convergence towards a limited number of standards for representing knowledge (metadata) about geospatial (and other) data objects and collections, there exist a variety of community conventions around the specific use of those standards and within specific data discovery and access systems. This combination of limited (but multiple) standards and conventions creates a challenge for system developers that aspire to participate in multiple data infrastrucutres, each of which may use a different combination of standards and conventions. While Extensible Markup Language (XML) is a shared standard for encoding most metadata, traditional direct XML transformations (XSLT) from one standard to another often result in an imperfect transfer of information due to incomplete mapping from one standard's content model to another. This paper presents the work at the University of New Mexico's Earth Data Analysis Center (EDAC) in which a unified data and metadata management system has been developed in support of the storage, discovery and access of heterogeneous data products. This system, the Geographic Storage, Transformation and Retrieval Engine (GSTORE) platform has adopted a polyglot database model in which a combination of relational and document-based databases are used to store both data and metadata, with some metadata stored in a custom XML schema designed as a superset of the requirements for multiple target metadata standards: ISO 19115-2/19139/19110/19119, FGCD CSDGM (both with and without remote sensing extensions) and Dublin Core. Metadata stored within this schema is complemented by additional service, format and publisher information that is dynamically "injected" into produced metadata documents when they are requested from the system. While mapping from the underlying common metadata schema is relatively straightforward, the generation of valid metadata within each target standard is necessary but not sufficient for integration into multiple data infrastructures, as has been demonstrated through EDAC's testing and deployment of metadata into multiple external systems: Data.Gov, the GEOSS Registry, the DataONE network, the DSpace based institutional repository at UNM and semantic mediation systems developed as part of the NASA ACCESS ELSeWEB project. Each of these systems requires valid metadata as a first step, but to make most effective use of the delivered metadata each also has a set of conventions that are specific to the system. This presentation will provide an overview of the underlying metadata management model, the processes and web services that have been developed to automatically generate metadata in a variety of standard formats and highlight some of the specific modifications made to the output metadata content to support the different conventions used by the multiple metadata integration endpoints.

Blind information-theoretic multiuser detection algorithms for DS-CDMA and WCDMA downlink systems.

PubMed

Waheed, Khuram; Salem, Fathi M

2005-07-01

Code division multiple access (CDMA) is based on the spread-spectrum technology and is a dominant air interface for 2.5G, 3G, and future wireless networks. For the CDMA downlink, the transmitted CDMA signals from the base station (BS) propagate through a noisy multipath fading communication channel before arriving at the receiver of the user equipment/mobile station (UE/MS). Classical CDMA single-user detection (SUD) algorithms implemented in the UE/MS receiver do not provide the required performance for modern high data-rate applications. In contrast, multi-user detection (MUD) approaches require a lot of a priori information not available to the UE/MS. In this paper, three promising adaptive Riemannian contra-variant (or natural) gradient based user detection approaches, capable of handling the highly dynamic wireless environments, are proposed. The first approach, blind multiuser detection (BMUD), is the process of simultaneously estimating multiple symbol sequences associated with all the users in the downlink of a CDMA communication system using only the received wireless data and without any knowledge of the user spreading codes. This approach is applicable to CDMA systems with relatively short spreading codes but becomes impractical for systems using long spreading codes. We also propose two other adaptive approaches, namely, RAKE -blind source recovery (RAKE-BSR) and RAKE-principal component analysis (RAKE-PCA) that fuse an adaptive stage into a standard RAKE receiver. This adaptation results in robust user detection algorithms with performance exceeding the linear minimum mean squared error (LMMSE) detectors for both Direct Sequence CDMA (DS-CDMA) and wide-band CDMA (WCDMA) systems under conditions of congestion, imprecise channel estimation and unmodeled multiple access interference (MAI).

Ultrasensitive and Multiple Disease-Related MicroRNA Detection Based on Tetrahedral DNA Nanostructures and Duplex-Specific Nuclease-Assisted Signal Amplification.

PubMed

Xu, Fang; Dong, Haifeng; Cao, Yu; Lu, Huiting; Meng, Xiangdan; Dai, Wenhao; Zhang, Xueji; Al-Ghanim, Khalid Abdullah; Mahboob, Shahid

2016-12-14

A highly sensitive and multiple microRNA (miRNA) detection method by combining three-dimensional (3D) DNA tetrahedron-structured probes (TSPs) to increase the probe reactivity and accessibility with duplex-specific nuclease (DSN) for signal amplification for sensitive miRNA detection was proposed. Briefly, 3D DNA TSPs labeled with different fluorescent dyes for specific target miRNA recognition were modified on a gold nanoparticle (GNP) surface to increase the reactivity and accessibility. Upon hybridization with a specific target, the TSPs immobilized on the GNP surface hybridized with the corresponding target miRNA to form DNA-RNA heteroduplexes, and the DSN can recognize the formed DNA-RNA heteroduplexes to hydrolyze the DNA in the heteroduplexes to produce a specific fluorescent signal corresponding to a specific miRNA, while the released target miRNA strands can initiate another cycle, resulting in a significant signal amplification for sensitive miRNA detection. Different targets can produce different fluorescent signals, leading to the development of a sensitive detection for multiple miRNAs in a homogeneous solution. Under optimized conditions, the proposed assay can simultaneously detect three different miRNAs in a homogeneous solution with a logarithmic linear range spanning 5 magnitudes (10 -12 -10 -16 ) and achieving a limit of detection down to attomolar concentrations. Meanwhile, the proposed miRNA assay exhibited the capability of discriminating single bases (three bases mismatched miRNAs) and showed good eligibility in the analysis of miRNAs extracted from cell lysates and miRNAs in cell incubation media, which indicates its potential use in biomedical research and clinical analysis.

Food-Based Interventions to Modify Diet Quality and Diversity to Address Multiple Micronutrient Deficiency.

PubMed

Nair, Madhavan K; Augustine, Little Flower; Konapur, Archana

2015-01-01

Global data indicate a high prevalence of hidden hunger among population. Deficiencies of certain micronutrients such as folic acid, iodine, iron, and vitamin A have long lasting effects on growth and development and therefore have been a National priority from many decades. The strategy implemented so far limits to the use of supplemental sources or fortified foods in alleviating the burden of deficiencies. These approaches however undermine the food-based strategies involving dietary diversification as the long-term sustainable strategy. There is lack of understanding on the level of evidence needed to implement such strategies and the level of monitoring required for impact evaluation. Dietary diversity concerns how to ensure access for each individual to a quality and safe diet with adequate macro- and micronutrients. The key to success in using dietary diversity as a strategy to tackle hidden hunger is in integrating it with the principles of bioavailability, translated to efficient food synergies with due emphasis on food accessibility, affordability, and outdoor physical activity/life style modifications. Promoting enabling environment and sustainable agriculture is crucial for practicing dietary diversification with behavior change communication as an integral segment. It can be concluded that food-based strategies require careful understanding of the factors associated with it and moderate it to form an effective strategy for controlling multiple micronutrient deficiencies.

Design and implementation of a fault-tolerant and dynamic metadata database for clinical trials

NASA Astrophysics Data System (ADS)

Lee, J.; Zhou, Z.; Talini, E.; Documet, J.; Liu, B.

2007-03-01

In recent imaging-based clinical trials, quantitative image analysis (QIA) and computer-aided diagnosis (CAD) methods are increasing in productivity due to higher resolution imaging capabilities. A radiology core doing clinical trials have been analyzing more treatment methods and there is a growing quantity of metadata that need to be stored and managed. These radiology centers are also collaborating with many off-site imaging field sites and need a way to communicate metadata between one another in a secure infrastructure. Our solution is to implement a data storage grid with a fault-tolerant and dynamic metadata database design to unify metadata from different clinical trial experiments and field sites. Although metadata from images follow the DICOM standard, clinical trials also produce metadata specific to regions-of-interest and quantitative image analysis. We have implemented a data access and integration (DAI) server layer where multiple field sites can access multiple metadata databases in the data grid through a single web-based grid service. The centralization of metadata database management simplifies the task of adding new databases into the grid and also decreases the risk of configuration errors seen in peer-to-peer grids. In this paper, we address the design and implementation of a data grid metadata storage that has fault-tolerance and dynamic integration for imaging-based clinical trials.

Food-Based Interventions to Modify Diet Quality and Diversity to Address Multiple Micronutrient Deficiency

PubMed Central

Nair, Madhavan K.; Augustine, Little Flower; Konapur, Archana

2016-01-01

Global data indicate a high prevalence of hidden hunger among population. Deficiencies of certain micronutrients such as folic acid, iodine, iron, and vitamin A have long lasting effects on growth and development and therefore have been a National priority from many decades. The strategy implemented so far limits to the use of supplemental sources or fortified foods in alleviating the burden of deficiencies. These approaches however undermine the food-based strategies involving dietary diversification as the long-term sustainable strategy. There is lack of understanding on the level of evidence needed to implement such strategies and the level of monitoring required for impact evaluation. Dietary diversity concerns how to ensure access for each individual to a quality and safe diet with adequate macro- and micronutrients. The key to success in using dietary diversity as a strategy to tackle hidden hunger is in integrating it with the principles of bioavailability, translated to efficient food synergies with due emphasis on food accessibility, affordability, and outdoor physical activity/life style modifications. Promoting enabling environment and sustainable agriculture is crucial for practicing dietary diversification with behavior change communication as an integral segment. It can be concluded that food-based strategies require careful understanding of the factors associated with it and moderate it to form an effective strategy for controlling multiple micronutrient deficiencies. PMID:26779472

Cardinality enhancement utilizing Sequential Algorithm (SeQ) code in OCDMA system

NASA Astrophysics Data System (ADS)

Fazlina, C. A. S.; Rashidi, C. B. M.; Rahman, A. K.; Aljunid, S. A.

2017-11-01

Optical Code Division Multiple Access (OCDMA) has been important with increasing demand for high capacity and speed for communication in optical networks because of OCDMA technique high efficiency that can be achieved, hence fibre bandwidth is fully used. In this paper we will focus on Sequential Algorithm (SeQ) code with AND detection technique using Optisystem design tool. The result revealed SeQ code capable to eliminate Multiple Access Interference (MAI) and improve Bit Error Rate (BER), Phase Induced Intensity Noise (PIIN) and orthogonally between users in the system. From the results, SeQ shows good performance of BER and capable to accommodate 190 numbers of simultaneous users contrast with existing code. Thus, SeQ code have enhanced the system about 36% and 111% of FCC and DCS code. In addition, SeQ have good BER performance 10-25 at 155 Mbps in comparison with 622 Mbps, 1 Gbps and 2 Gbps bit rate. From the plot graph, 155 Mbps bit rate is suitable enough speed for FTTH and LAN networks. Resolution can be made based on the superior performance of SeQ code. Thus, these codes will give an opportunity in OCDMA system for better quality of service in an optical access network for future generation's usage

The Tubulin-Based-Polymorphism Method Provides a Simple and Effective Alternative to the Genomic Profiling of Grape

PubMed Central

Mastromauro, Francesco; Gianì, Silvia; Morello, Laura

2016-01-01

The TBP (Tubulin-Based-Polymorphism) method, based on a nuclear ILP (Intron-Length-Polymorphism) molecular marker, has been used for genotyping 37 accessions of the genus Vitis inclusive of different species, rootstocks, wild and cultivated subspecies. A distinct DNA barcode made up by a different number of amplicons, was attributed to each of the different accessions. TBP data were compared with those obtained, with the use of an internationally validated set of six SSR markers. Genetic relationships among the different accessions, dendrogram distributions, correlation values and polymorphic index values (PICs) were definitively comparable when not in favor of TBP. Such an experimental consistency is based upon a genomic organization of the multiple members of the β-tubulin gene family, the targets of TBP-mediated amplification, that is conserved in Vitis as in any other plant species. The TBP amplicons can actually be used as a useful source of sequence polymorphisms for generating primer pairs capable of identifying specific cultivars in a simple assay. An example for the identification of the ‘Sangiovese’ cv. is reported. More generally, these data are discussed in terms of the actual advantages that the introduction of the TBP method in the field of grape characterization and genotyping can provide. PMID:27643687

Direct data access protocols benchmarking on DPM

NASA Astrophysics Data System (ADS)

Furano, Fabrizio; Devresse, Adrien; Keeble, Oliver; Mancinelli, Valentina

2015-12-01

The Disk Pool Manager is an example of a multi-protocol, multi-VO system for data access on the Grid that went though a considerable technical evolution in the last years. Among other features, its architecture offers the opportunity of testing its different data access frontends under exactly the same conditions, including hardware and backend software. This characteristic inspired the idea of collecting monitoring information from various testbeds in order to benchmark the behaviour of the HTTP and Xrootd protocols for the use case of data analysis, batch or interactive. A source of information is the set of continuous tests that are run towards the worldwide endpoints belonging to the DPM Collaboration, which accumulated relevant statistics in its first year of activity. On top of that, the DPM releases are based on multiple levels of automated testing that include performance benchmarks of various kinds, executed regularly every day. At the same time, the recent releases of DPM can report monitoring information about any data access protocol to the same monitoring infrastructure that is used to monitor the Xrootd deployments. Our goal is to evaluate under which circumstances the HTTP-based protocols can be good enough for batch or interactive data access. In this contribution we show and discuss the results that our test systems have collected under the circumstances that include ROOT analyses using TTreeCache and stress tests on the metadata performance.

Holographic 3D multi-spot two-photon excitation for fast optical stimulation in brain

NASA Astrophysics Data System (ADS)

Takiguchi, Yu; Toyoda, Haruyoshi

2017-04-01

We report here a holographic high speed accessing microscope of sensory-driven synaptic activity across all inputs to single living neurons in the context of the intact cerebral cortex. This system is based on holographic multiple beam generation with spatial light modulator, we have demonstrated performance of the holographic excitation efficiency in several in vitro prototype system. 3D weighted iterative Fourier Transform method using the Ewald sphere in consideration of calculation speed has been adopted; multiple locations can be patterned in 3D with single hologram. Standard deviation of intensities of spots are still large due to the aberration of the system and/or hologram calculation, we successfully excited multiple locations of neurons in living mouse brain to monitor the calcium signals.

Unified tensor model for space-frequency spreading-multiplexing (SFSM) MIMO communication systems

NASA Astrophysics Data System (ADS)

de Almeida, André LF; Favier, Gérard

2013-12-01

This paper presents a unified tensor model for space-frequency spreading-multiplexing (SFSM) multiple-input multiple-output (MIMO) wireless communication systems that combine space- and frequency-domain spreadings, followed by a space-frequency multiplexing. Spreading across space (transmit antennas) and frequency (subcarriers) adds resilience against deep channel fades and provides space and frequency diversities, while orthogonal space-frequency multiplexing enables multi-stream transmission. We adopt a tensor-based formulation for the proposed SFSM MIMO system that incorporates space, frequency, time, and code dimensions by means of the parallel factor model. The developed SFSM tensor model unifies the tensorial formulation of some existing multiple-access/multicarrier MIMO signaling schemes as special cases, while revealing interesting tradeoffs due to combined space, frequency, and time diversities which are of practical relevance for joint symbol-channel-code estimation. The performance of the proposed SFSM MIMO system using either a zero forcing receiver or a semi-blind tensor-based receiver is illustrated by means of computer simulation results under realistic channel and system parameters.

Multichannel Baseband Processor for Wideband CDMA

NASA Astrophysics Data System (ADS)

Jalloul, Louay M. A.; Lin, Jim

2005-12-01

The system architecture of the cellular base station modem engine (CBME) is described. The CBME is a single-chip multichannel transceiver capable of processing and demodulating signals from multiple users simultaneously. It is optimized to process different classes of code-division multiple-access (CDMA) signals. The paper will show that through key functional system partitioning, tightly coupled small digital signal processing cores, and time-sliced reuse architecture, CBME is able to achieve a high degree of algorithmic flexibility while maintaining efficiency. The paper will also highlight the implementation and verification aspects of the CBME chip design. In this paper, wideband CDMA is used as an example to demonstrate the architecture concept.

Adaptive Transmission and Channel Modeling for Frequency Hopping Communications

DTIC Science & Technology

2009-09-21

proposed adaptive transmission method has much greater system capacity than conventional non-adaptive MC direct- sequence ( DS )- CDMA system. • We...several mobile radio systems. First, a new improved allocation algorithm was proposed for multicarrier code-division multiple access (MC- CDMA ) system...Multicarrier code-division multiple access (MC- CDMA ) system with adaptive frequency hopping (AFH) has attracted attention of researchers due to its

Perspectives of Patients, Clinicians, and Health System Leaders on Changes Needed to Improve the Health Care and Outcomes of Older Adults With Multiple Chronic Conditions.

PubMed

Ferris, Rosie; Blaum, Caroline; Kiwak, Eliza; Austin, Janet; Esterson, Jessica; Harkless, Gene; Oftedahl, Gary; Parchman, Michael; Van Ness, Peter H; Tinetti, Mary E

2018-06-01

To ascertain perspectives of multiple stakeholders on contributors to inappropriate care for older adults with multiple chronic conditions. Perspectives of 36 purposively sampled patients, clinicians, health systems, and payers were elicited. Data analysis followed a constant comparative method. Structural factors triggering burden and fragmentation include disease-based quality metrics and need to interact with multiple clinicians. The key cultural barrier identified is the assumption that "physicians know best." Inappropriate decision making may result from inattention to trade-offs and adherence to multiple disease guidelines. Stakeholders recommended changes in culture, structure, and decision making. Care options and quality metrics should reflect a focus on patients' priorities. Clinician-patient partnerships should reflect patients knowing their health goals and clinicians knowing how to achieve them. Access to specialty expertise should not require visits. Stakeholders' recommendations suggest health care redesigns that incorporate patients' health priorities into care decisions and realign relationships across patients and clinicians.

Next generation communications satellites: Multiple access and network studies

NASA Technical Reports Server (NTRS)

Stern, T. E.; Schwartz, M.; Meadows, H. E.; Ahmadi, H. K.; Gadre, J. G.; Gopal, I. S.; Matsmo, K.

1980-01-01

Following an overview of issues involved in the choice of promising system architectures for efficient communication with multiple small inexpensive Earth stations serving hetergeneous user populations, performance evaluation via analysis and simulation for six SS/TDMA (satellite-switched/time-division multiple access) system architectures is discussed. These configurations are chosen to exemplify the essential alternatives available in system design. Although the performance evaluation analyses are of fairly general applicability, whenever possible they are considered in the context of NASA's 30/20 GHz studies. Packet switched systems are considered, with the assumption that only a part of transponder capacit is devoted to packets, the integration of circuit and packet switched traffic being reserved for further study. Three types of station access are distinguished: fixed (FA), demand (DA), and random access (RA). Similarly, switching in the satellite can be assigned on a fixed (FS) or demand (DS) basis, or replaced by a buffered store-and-forward system (SF) onboard the satellite. Since not all access/switching combinations are practical, six systems are analyzed in detail: three FS SYSTEMS, FA/FS, DA/ES, RA/FS; one DS system, DA/DS; and two SF systems, FA/SF, DA/SF. Results are presented primarily in terms of delay-throughput characteristics.

A universal data access and protocol integration mechanism for smart home

NASA Astrophysics Data System (ADS)

Shao, Pengfei; Yang, Qi; Zhang, Xuan

2013-03-01

With the lack of standardized or completely missing communication interfaces in home electronics, there is no perfect solution to address every aspect in smart homes based on existing protocols and technologies. In addition, the central control unit (CCU) of smart home system working point-to-point between the multiple application interfaces and the underlying hardware interfaces leads to its complicated architecture and unpleasant performance. A flexible data access and protocol integration mechanism is required. The current paper offers a universal, comprehensive data access and protocol integration mechanism for a smart home. The universal mechanism works as a middleware adapter with unified agreements of the communication interfaces and protocols, offers an abstraction of the application level from the hardware specific and decoupling the hardware interface modules from the application level. Further abstraction for the application interfaces and the underlying hardware interfaces are executed based on adaption layer to provide unified interfaces for more flexible user applications and hardware protocol integration. This new universal mechanism fundamentally changes the architecture of the smart home and in some way meets the practical requirement of smart homes more flexible and desirable.

Predicting impact of multi-paths on phase change in map-based vehicular ad hoc networks

NASA Astrophysics Data System (ADS)

Rahmes, Mark; Lemieux, George; Sonnenberg, Jerome; Chester, David B.

2014-05-01

Dynamic Spectrum Access, which through its ability to adapt the operating frequency of a radio, is widely believed to be a solution to the limited spectrum problem. Mobile Ad Hoc Networks (MANETs) can extend high capacity mobile communications over large areas where fixed and tethered-mobile systems are not available. In one use case with high potential impact cognitive radio employs spectrum sensing to facilitate identification of allocated frequencies not currently accessed by their primary users. Primary users own the rights to radiate at a specific frequency and geographic location, secondary users opportunistically attempt to radiate at a specific frequency when the primary user is not using it. We quantify optimal signal detection in map based cognitive radio networks with multiple rapidly varying phase changes and multiple orthogonal signals. Doppler shift occurs due to reflection, scattering, and rapid vehicle movement. Path propagation as well as vehicle movement produces either constructive or destructive interference with the incident wave. Our signal detection algorithms can assist the Doppler spread compensation algorithm by deciding how many phase changes in signals are present in a selected band of interest. Additionally we can populate a spatial radio environment map (REM) database with known information that can be leveraged in an ad hoc network to facilitate Dynamic Spectrum Access. We show how topography can help predict the impact of multi-paths on phase change, as well as about the prediction from dense traffic areas. Utilization of high resolution geospatial data layers in RF propagation analysis is directly applicable.

Research on an uplink carrier sense multiple access algorithm of large indoor visible light communication networks based on an optical hard core point process.

PubMed

Nan, Zhufen; Chi, Xuefen

2016-12-20

The IEEE 802.15.7 protocol suggests that it could coordinate the channel access process based on the competitive method of carrier sensing. However, the directionality of light and randomness of diffuse reflection would give rise to a serious imperfect carrier sense (ICS) problem [e.g., hidden node (HN) problem and exposed node (EN) problem], which brings great challenges in realizing the optical carrier sense multiple access (CSMA) mechanism. In this paper, the carrier sense process implemented by diffuse reflection light is modeled as the choice of independent sets. We establish an ICS model with the presence of ENs and HNs for the multi-point to multi-point visible light communication (VLC) uplink communications system. Considering the severe optical ICS problem, an optical hard core point process (OHCPP) is developed, which characterizes the optical CSMA for the indoor VLC uplink communications system. Due to the limited coverage of the transmitted optical signal, in our OHCPP, the ENs within the transmitters' carrier sense region could be retained provided that they could not corrupt the ongoing communications. Moreover, because of the directionality of both light emitting diode (LED) transmitters and receivers, theoretical analysis of the HN problem becomes difficult. In this paper, we derive the closed-form expression for approximating the outage probability and transmission capacity of VLC networks with the presence of HNs and ENs. Simulation results validate the analysis and also show the existence of an optimal physical carrier-sensing threshold that maximizes the transmission capacity for a given emission angle of LED.

Moving NASA Remote Sensing Data to the GIS Environment for Health Studies

NASA Technical Reports Server (NTRS)

Vicente, Gilberto A.; Maynard, Nancy G.

2003-01-01

There has been an increasing demand by the health community for improved data on many different environmental factors relevant to the links between the environment and disease occurrence and transmission. These data are important for GIS-based monitoring, risk mapping, and surveillance of epidemiological parameters on a large number of different spatial, temporal, and spectral resolutions. Accordingly, NASA is developing new approaches to data collection and distribution in order to improve access to multiple sources of data streams to increase spatial and temporal coverage. Methods are being developed to incorporate different, scalable capabilities to handle multiple data sources by adding, deleting and replacing components as required as well as associated tools for their management. An approach has been to search for innovative solutions focused on the creation, use and manipulation of data stored in many different archives. These include data transformation and combination as well as data and information tools that can assist the public health and science community to use existing and anticipated products in new and flexible ways. This presentation will provide an inventory of geophysical parameters derived from satellite remote sensing sensors that are useful for GIS-based public health studies. The presentation will also discuss the physical and scientific limitations of access to and use of these data for health applications such as resolution and format differences, lack of software interoperability, data access problems. Finally, there will be a summary of the recent steps the NASA program has taken to bring NASA-generated satellite products to a wider range of users in the GIS community.

The Sound Access Parent Outcomes Instrument (SAPOI): Construction of a new instrument for children with severe multiple disabilities who use cochlear implants or hearing aids.

PubMed

Hayward, Denyse V; Ritter, Kathryn; Mousavi, Amin; Vatanapour, Shabnam

2016-01-01

To report on the Phase 2 development of the Sound Access Parent Outcomes Instrument (SAPOI), a new instrument focused on formalizing outcomes that parents of children with severe multiple disabilities (SMD) who use amplification prioritize as important. Phase 2 of this project involved item selection and refinement of the SAPOI based on (a) Phase 1 study participant input, (b) clinical specialist feedback, and (c) test-retest instrument reliability. Phase 1 participant responses were utilized to construct a draft version of the SAPOI. Next, clinical specialists examined the instrument for content validity and utility and instrument reliability was examined through a test-retest process with parents of children with SMD. The draft SAPOI was constructed based on Phase 1 participant input. Clinical specialists supported content validity and utility of the instrument and the inclusion of 19 additional items across four categories, namely Child Affect, Child Interaction, Parent Well-being, and Child's Device Use. The SAPOI was completed twice at one-month intervals by parents of children with SMD to examine instrument reliability across the four categories (Child Affect, Child Interaction, Parent Well-being, and Child's Device Use). Instrument reliability was strong-to-excellent across all four sections. The SAPOI shows promise as a much-needed addition to the assessment battery currently used for children with SMD who use cochlear implants and hearing aids. It provides valuable information regarding outcomes resulting from access to sound in this population that currently used assessments do not identify.

Multi-PON access network using a coarse AWG for smooth migration from TDM to WDM PON

NASA Astrophysics Data System (ADS)

Shachaf, Y.; Chang, C.-H.; Kourtessis, P.; Senior, J. M.

2007-06-01

An interoperable access network architecture based on a coarse array waveguide grating (AWG) is described, displaying dynamic wavelength assignment to manage the network load across multiple PONs. The multi-PON architecture utilizes coarse Gaussian channels of an AWG to facilitate scalability and smooth migration path between TDM and WDM PONs. Network simulations of a cross-operational protocol platform confirmed successful routing of individual PON clusters through 7 nm-wide passband windows of the AWG. Furthermore, polarization-dependent wavelength shift and phase errors of the device proved not to impose restrain on the routing performance. Optical transmission tests at 2.5 Gbit/s for distances up to 20 km are demonstrated.

Shared Medical Imaging Repositories.

PubMed

Lebre, Rui; Bastião, Luís; Costa, Carlos

2018-01-01

This article describes the implementation of a solution for the integration of ownership concept and access control over medical imaging resources, making possible the centralization of multiple instances of repositories. The proposed architecture allows the association of permissions to repository resources and delegation of rights to third entities. It includes a programmatic interface for management of proposed services, made available through web services, with the ability to create, read, update and remove all components resulting from the architecture. The resulting work is a role-based access control mechanism that was integrated with Dicoogle Open-Source Project. The solution has several application scenarios like, for instance, collaborative platforms for research and tele-radiology services deployed at Cloud.

Ruthenium-Catalyzed Cascade C—H Functionalization of Phenylacetophenones**

PubMed Central

Mehta, Vaibhav P; García-López, José-Antonio; Greaney, Michael F

2014-01-01

Three orthogonal cascade C—H functionalization processes are described, based on ruthenium-catalyzed C—H alkenylation. 1-Indanones, indeno indenes, and indeno furanones were accessed through cascade pathways by using arylacetophenones as substrates under conditions of catalytic [{Ru(p-cymene)Cl2}2] and stoichiometric Cu(OAc)2. Each transformation uses C—H functionalization methods to form C—C bonds sequentially, with the indeno furanone synthesis featuring a C—O bond formation as the terminating step. This work demonstrates the power of ruthenium-catalyzed alkenylation as a platform reaction to develop more complex transformations, with multiple C—H functionalization steps taking place in a single operation to access novel carbocyclic structures. PMID:24453063

Design of a graphical user interface for an intelligent multimedia information system for radiology research

NASA Astrophysics Data System (ADS)

Taira, Ricky K.; Wong, Clement; Johnson, David; Bhushan, Vikas; Rivera, Monica; Huang, Lu J.; Aberle, Denise R.; Cardenas, Alfonso F.; Chu, Wesley W.

1995-05-01

With the increase in the volume and distribution of images and text available in PACS and medical electronic health-care environments it becomes increasingly important to maintain indexes that summarize the content of these multi-media documents. Such indices are necessary to quickly locate relevant patient cases for research, patient management, and teaching. The goal of this project is to develop an intelligent document retrieval system that allows researchers to request for patient cases based on document content. Thus we wish to retrieve patient cases from electronic information archives that could include a combined specification of patient demographics, low level radiologic findings (size, shape, number), intermediate-level radiologic findings (e.g., atelectasis, infiltrates, etc.) and/or high-level pathology constraints (e.g., well-differentiated small cell carcinoma). The cases could be distributed among multiple heterogeneous databases such as PACS, RIS, and HIS. Content- based retrieval systems go beyond the capabilities of simple key-word or string-based retrieval matching systems. These systems require a knowledge base to comprehend the generality/specificity of a concept (thus knowing the subclasses or related concepts to a given concept) and knowledge of the various string representations for each concept (i.e., synonyms, lexical variants, etc.). We have previously reported on a data integration mediation layer that allows transparent access to multiple heterogeneous distributed medical databases (HIS, RIS, and PACS). The data access layer of our architecture currently has limited query processing capabilities. Given a patient hospital identification number, the access mediation layer collects all documents in RIS and HIS and returns this information to a specified workstation location. In this paper we report on our efforts to extend the query processing capabilities of the system by creation of custom query interfaces, an intelligent query processing engine, and a document-content index that can be generated automatically (i.e., no manual authoring or changes to the normal clinical protocols).

Developing an EarthCube Governance Structure for Big Data Preservation and Access

NASA Astrophysics Data System (ADS)

Leetaru, H. E.; Leetaru, K. H.

2012-12-01

The underlying vision of the NSF EarthCube initiative is of an enduring resource serving the needs of the earth sciences for today and the future. We must therefore view this effort through the lens of what the earth sciences will need tomorrow and on how the underlying processes of data compilation, preservation, and access interplay with the scientific processes within the communities EarthCube will serve. Key issues that must be incorporated into the EarthCube governance structure include authentication, retrieval, and unintended use cases, the emerging role of whole-corpus data mining, and how inventory, citation, and archive practices will impact the ability of scientists to use EarthCube's collections into the future. According to the National Academies, the US federal government spends over $140 billion dollars a year in support of the nation's research base. Yet, a critical issue confronting all of the major scientific disciplines in building upon this investment is the lack of processes that guide how data are preserved for the long-term, ensuring that studies can be replicated and that experimental data remains accessible as new analytic methods become available or theories evolve. As datasets are used years or even decades after their creation, far richer metadata is needed to describe the underlying simulation, smoothing algorithms or bounding parameters of the data collection process. This is even truer as data are increasingly used outside their intended disciplines, as geoscience researchers apply algorithms from one discipline to datasets from another, where their analytical techniques may make extensive assumptions about the data. As science becomes increasingly interdisciplinary and emerging computational approaches begin applying whole-corpus methodologies and blending multiple archives together, we are facing new data access modalities distinct from the needs of the past, drawing into focus the question of centralized versus distributed architectures. In the past geoscience data have been distributed, with each site maintaining its own collections and centralized inventory metadata supporting discovery. This was based on the historical search-browse-download modality where access was primarily to download a copy to a researcher's own machine and datasets were measured in gigabytes. New "big data" approaches to the geosciences are already demonstrating the need to analyze the entirety of multiple collections from multiple sites totaling hundreds of terabytes in size. Yet, datasets are outpacing the ability of networks to share them, forcing a new paradigm in high-performance computing where computation must migrate to centralized data stores. The next generation of geoscientists are going to need a system designed for exploring and understanding data from multiple scientific domains and vantages where data are preserved for decades. We are not alone in this endeavor and there are many lessons we can learn from similar initiatives such as more than 40 years of governance policies for data warehouses and 15 years of open web archives, all of which face the same challenges. The entire EarthCube project will fail if the new governance structure does not account for the needs of integrated cyberinfrastructure that allows big data to stored, archived, analyzed, and made accessible to large numbers of scientists.

Orthogonal Pilot Channel Using Combination of FDMA and CDMA in Single-Carrier FDMA-Based Evolved UTRA Uplink

NASA Astrophysics Data System (ADS)

Kawamura, Teruo; Kishiyama, Yoshihisa; Higuchi, Kenichi; Sawahashi, Mamoru

In the Evolved UTRA (UMTS Terrestrial Radio Access) uplink, single-carrier frequency division multiple access (SC-FDMA) radio access was adopted owing to its advantageous low peak-to-average power ratio (PAPR) feature, which leads to wide coverage area provisioning with limited peak transmission power of user equipments. This paper proposes orthogonal pilot channel generation using the combination of FDMA and CDMA in the SC-FDMA-based Evolved UTRA uplink. In the proposed method, we employ distributed FDMA transmission for simultaneous accessing users with different transmission bandwidths, and employ CDMA transmission for simultaneous accessing users with identical transmission bandwidth. Moreover, we apply a code sequence with a good auto-correlation property such as a Constant Amplitude Zero Auto-Correlation (CAZAC) sequence employing a cyclic shift to increase the number of sequences. Simulation results show that the average packet error rate performance using an orthogonal pilot channel with the combination of FDMA and CDMA in a six-user environment, i. e., four users each with a 1.25-MHz transmission bandwidth and two users each with a 5-MHz transmission bandwidth, employing turbo coding with the coding r of R=1/2 and QPSK and 16QAM data modulation coincides well with that in a single-user environment with the same transmission bandwidth. We show that the proposed orthogonal pilot channel structure using the combination of distributed FDMA and CDMA transmissions and the application of the CAZAC sequence is effective in the SC-FDMA-based Evolved UTRA uplink.

Understanding and improving access to prompt and effective malaria treatment and care in rural Tanzania: the ACCESS Programme

PubMed Central

Hetzel, Manuel W; Iteba, Nelly; Makemba, Ahmed; Mshana, Christopher; Lengeler, Christian; Obrist, Brigit; Schulze, Alexander; Nathan, Rose; Dillip, Angel; Alba, Sandra; Mayumana, Iddy; Khatib, Rashid A; Njau, Joseph D; Mshinda, Hassan

2007-01-01

Background Prompt access to effective treatment is central in the fight against malaria. However, a variety of interlinked factors at household and health system level influence access to timely and appropriate treatment and care. Furthermore, access may be influenced by global and national health policies. As a consequence, many malaria episodes in highly endemic countries are not treated appropriately. Project The ACCESS Programme aims at understanding and improving access to prompt and effective malaria treatment and care in a rural Tanzanian setting. The programme's strategy is based on a set of integrated interventions, including social marketing for improved care seeking at community level as well as strengthening of quality of care at health facilities. This is complemented by a project that aims to improve the performance of drug stores. The interventions are accompanied by a comprehensive set of monitoring and evaluation activities measuring the programme's performance and (health) impact. Baseline data demonstrated heterogeneity in the availability of malaria treatment, unavailability of medicines and treatment providers in certain areas as well as quality problems with regard to drugs and services. Conclusion The ACCESS Programme is a combination of multiple complementary interventions with a strong evaluation component. With this approach, ACCESS aims to contribute to the development of a more comprehensive access framework and to inform and support public health professionals and policy-makers in the delivery of improved health services. PMID:17603898

A Portable Farmland Information Collection System with Multiple Sensors.

PubMed

Zhang, Jianfeng; Hu, Jinyang; Huang, Lvwen; Zhang, Zhiyong; Ma, Yimian

2016-10-22

Precision agriculture is the trend of modern agriculture, and it is also one of the important ways to realize the sustainable development of agriculture. In order to meet the production requirements of precision agriculture-efficient use of agricultural resources, and improving the crop yields and quality-some necessary field information in crop growth environment needs to be collected and monitored. In this paper, a farmland information collection system is developed, which includes a portable farmland information collection device based on STM32 (a 32-bit comprehensive range of microcontrollers based on ARM Crotex-M3), a remote server and a mobile phone APP. The device realizes the function of portable and mobile collecting of multiple parameters farmland information, such as chlorophyll content of crop leaves, air temperature, air humidity, and light intensity. UM220-III (Unicore Communication Inc., Beijing, China) is used to realize the positioning based on BDS/GPS (BeiDou Navigation Satellite System, BDS/Global Positioning System, GPS) dual-mode navigation and positioning system, and the CDMA (Code Division Multiple Access, CDMA) wireless communication module is adopted to realize the real-time remote transmission. The portable multi-function farmland information collection system is real-time, accurate, and easy to use to collect farmland information and multiple information parameters of crops.

A Portable Farmland Information Collection System with Multiple Sensors

PubMed Central

Zhang, Jianfeng; Hu, Jinyang; Huang, Lvwen; Zhang, Zhiyong; Ma, Yimian

2016-01-01

Precision agriculture is the trend of modern agriculture, and it is also one of the important ways to realize the sustainable development of agriculture. In order to meet the production requirements of precision agriculture—efficient use of agricultural resources, and improving the crop yields and quality—some necessary field information in crop growth environment needs to be collected and monitored. In this paper, a farmland information collection system is developed, which includes a portable farmland information collection device based on STM32 (a 32-bit comprehensive range of microcontrollers based on ARM Crotex-M3), a remote server and a mobile phone APP. The device realizes the function of portable and mobile collecting of multiple parameters farmland information, such as chlorophyll content of crop leaves, air temperature, air humidity, and light intensity. UM220-III (Unicore Communication Inc., Beijing, China) is used to realize the positioning based on BDS/GPS (BeiDou Navigation Satellite System, BDS/Global Positioning System, GPS) dual-mode navigation and positioning system, and the CDMA (Code Division Multiple Access, CDMA) wireless communication module is adopted to realize the real-time remote transmission. The portable multi-function farmland information collection system is real-time, accurate, and easy to use to collect farmland information and multiple information parameters of crops. PMID:27782076

A multiple multicomponent approach to chimeric peptide-peptoid podands.

PubMed

Rivera, Daniel G; León, Fredy; Concepción, Odette; Morales, Fidel E; Wessjohann, Ludger A

2013-05-10

The success of multi-armed, peptide-based receptors in supramolecular chemistry traditionally is not only based on the sequence but equally on an appropriate positioning of various peptidic chains to create a multivalent array of binding elements. As a faster, more versatile and alternative access toward (pseudo)peptidic receptors, a new approach based on multiple Ugi four-component reactions (Ugi-4CR) is proposed as a means of simultaneously incorporating several binding and catalytic elements into organizing scaffolds. By employing α-amino acids either as the amino or acid components of the Ugi-4CRs, this multiple multicomponent process allows for the one-pot assembly of podands bearing chimeric peptide-peptoid chains as appended arms. Tripodal, bowl-shaped, and concave polyfunctional skeletons are employed as topologically varied platforms for positioning the multiple peptidic chains formed by Ugi-4CRs. In a similar approach, steroidal building blocks with several axially-oriented isocyano groups are synthesized and utilized to align the chimeric chains with conformational constrains, thus providing an alternative to the classical peptido-steroidal receptors. The branched and hybrid peptide-peptoid appendages allow new possibilities for both rational design and combinatorial production of synthetic receptors. The concept is also expandable to other multicomponent reactions. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Distributed magnetic field positioning system using code division multiple access

NASA Technical Reports Server (NTRS)

Prigge, Eric A. (Inventor)

2003-01-01

An apparatus and methods for a magnetic field positioning system use a fundamentally different, and advantageous, signal structure and multiple access method, known as Code Division Multiple Access (CDMA). This signal architecture, when combined with processing methods, leads to advantages over the existing technologies, especially when applied to a system with a large number of magnetic field generators (beacons). Beacons at known positions generate coded magnetic fields, and a magnetic sensor measures a sum field and decomposes it into component fields to determine the sensor position and orientation. The apparatus and methods can have a large `building-sized` coverage area. The system allows for numerous beacons to be distributed throughout an area at a number of different locations. A method to estimate position and attitude, with no prior knowledge, uses dipole fields produced by these beacons in different locations.

The Digital Divide and Patient Portals: Internet Access Explained Differences in Patient Portal Use for Secure Messaging by Age, Race, and Income.

PubMed

Graetz, Ilana; Gordon, Nancy; Fung, Vick; Hamity, Courtnee; Reed, Mary E

2016-08-01

Online access to health records and the ability to exchange secure messages with physicians can improve patient engagement and outcomes; however, the digital divide could limit access to web-based portals among disadvantaged groups. To understand whether sociodemographic differences in patient portal use for secure messaging can be explained by differences in internet access and care preferences. Cross-sectional survey to examine the association between patient sociodemographic characteristics and internet access and care preferences; then, the association between sociodemographic characteristics and secure message use with and without adjusting for internet access and care preference. One thousand forty-one patients with chronic conditions in a large integrated health care delivery system (76% response rate). Internet access, portal use for secure messaging, preference for in-person or online care, and sociodemographic and health characteristics. Internet access and preference mediated some of the differences in secure message use by age, race, and income. For example, using own computer to access the internet explained 52% of the association between race and secure message use and 60% of the association between income and use (Sobel-Goodman mediation test, P<0.001 for both). Education and sex-related differences in portal use remained statistically significant when controlling for internet access and preference. As the availability and use of patient portals increase, it is important to understand which patients have limited access and the barriers they may face. Improving internet access and making portals available across multiple platforms, including mobile, may reduce some disparities in secure message use.

Feedback power control strategies in wireless sensor networks with joint channel decoding.

PubMed

Abrardo, Andrea; Ferrari, Gianluigi; Martalò, Marco; Perna, Fabio

2009-01-01

In this paper, we derive feedback power control strategies for block-faded multiple access schemes with correlated sources and joint channel decoding (JCD). In particular, upon the derivation of the feasible signal-to-noise ratio (SNR) region for the considered multiple access schemes, i.e., the multidimensional SNR region where error-free communications are, in principle, possible, two feedback power control strategies are proposed: (i) a classical feedback power control strategy, which aims at equalizing all link SNRs at the access point (AP), and (ii) an innovative optimized feedback power control strategy, which tries to make the network operational point fall in the feasible SNR region at the lowest overall transmit energy consumption. These strategies will be referred to as "balanced SNR" and "unbalanced SNR," respectively. While they require, in principle, an unlimited power control range at the sources, we also propose practical versions with a limited power control range. We preliminary consider a scenario with orthogonal links and ideal feedback. Then, we analyze the robustness of the proposed power control strategies to possible non-idealities, in terms of residual multiple access interference and noisy feedback channels. Finally, we successfully apply the proposed feedback power control strategies to a limiting case of the class of considered multiple access schemes, namely a central estimating officer (CEO) scenario, where the sensors observe noisy versions of a common binary information sequence and the AP's goal is to estimate this sequence by properly fusing the soft-output information output by the JCD algorithm.

Enabling Data Intensive Science through Service Oriented Science: Virtual Laboratories and Science Gateways

NASA Astrophysics Data System (ADS)

Lescinsky, D. T.; Wyborn, L. A.; Evans, B. J. K.; Allen, C.; Fraser, R.; Rankine, T.

2014-12-01

We present collaborative work on a generic, modular infrastructure for virtual laboratories (VLs, similar to science gateways) that combine online access to data, scientific code, and computing resources as services that support multiple data intensive scientific computing needs across a wide range of science disciplines. We are leveraging access to 10+ PB of earth science data on Lustre filesystems at Australia's National Computational Infrastructure (NCI) Research Data Storage Infrastructure (RDSI) node, co-located with NCI's 1.2 PFlop Raijin supercomputer and a 3000 CPU core research cloud. The development, maintenance and sustainability of VLs is best accomplished through modularisation and standardisation of interfaces between components. Our approach has been to break up tightly-coupled, specialised application packages into modules, with identified best techniques and algorithms repackaged either as data services or scientific tools that are accessible across domains. The data services can be used to manipulate, visualise and transform multiple data types whilst the scientific tools can be used in concert with multiple scientific codes. We are currently designing a scalable generic infrastructure that will handle scientific code as modularised services and thereby enable the rapid/easy deployment of new codes or versions of codes. The goal is to build open source libraries/collections of scientific tools, scripts and modelling codes that can be combined in specially designed deployments. Additional services in development include: provenance, publication of results, monitoring, workflow tools, etc. The generic VL infrastructure will be hosted at NCI, but can access alternative computing infrastructures (i.e., public/private cloud, HPC).The Virtual Geophysics Laboratory (VGL) was developed as a pilot project to demonstrate the underlying technology. This base is now being redesigned and generalised to develop a Virtual Hazards Impact and Risk Laboratory (VHIRL); any enhancements and new capabilities will be incorporated into a generic VL infrastructure. At same time, we are scoping seven new VLs and in the process, identifying other common components to prioritise and focus development.

The NOAO NVO Portal

NASA Astrophysics Data System (ADS)

Miller, C. J.; Gasson, D.; Fuentes, E.

2007-10-01

The NOAO NVO Portal is a web application for one-stop discovery, analysis, and access to VO-compliant imaging data and services. The current release allows for GUI-based discovery of nearly a half million images from archives such as the NOAO Science Archive, the Hubble Space Telescope WFPC2 and ACS instruments, XMM-Newton, Chandra, and ESO's INT Wide-Field Survey, among others. The NOAO Portal allows users to view image metadata, footprint wire-frames, FITS image previews, and provides one-click access to science quality imaging data throughout the entire sky via the Firefox web browser (i.e., no applet or code to download). Users can stage images from multiple archives at the NOAO NVO Portal for quick and easy bulk downloads. The NOAO NVO Portal also provides simplified and direct access to VO analysis services, such as the WESIX catalog generation service. We highlight the features of the NOAO NVO Portal (http://nvo.noao.edu).

Are referring doctors ready for enterprise and community wide immediate image and report access?

PubMed

Wadley, Brian D; Hayward, Ulrike; Trambert, Michael; Kywi, Alberto; Hartzman, Steve

2002-01-01

At most medical centers film-based radiology requires that single or multiple copies of patient exams and reports be distributed for results communication. A successful picture archiving and communication system (PACS) should provide a means to improve upon this inefficient paradigm, with universal access to imagery and exam results on demand at the user's convenience. Enterprise and community-wide experience with universal PACS access is reviewed. Referring physicians were surveyed about their experience with PACS, with regard to acceptance, productivity, frequency of usage, and impact on patient care. Web audit trails were used to assess physician usage. Film printing logs were reviewed. The filmless paradigm was highly regarded and frequently used by nearly all users. Significant productivity benefits were gleaned by all of the referring physicians. Patient quality of care benefitted from more efficient communication of results. Very small quantities of film were used for printing of exams, typically for patient copies.

Improving access to high-cost cancer drugs in Latin America: Much to be done.

PubMed

Ruiz, Rossana; Strasser-Weippl, Kathrin; Touya, Diego; Herrero Vincent, Carmen; Hernandez-Blanquisett, Abraham; St Louis, Jessica; Bukowski, Alexandra; Goss, Paul E

2017-04-15

Lack of access to high-cost medications is a complex issue at the intersection of economics, medicine, politics, and ethics, and it poses a significant threat to global health care. The problem is even more significant in low- and middle-income countries, such as those in Latin America, where governments and individuals struggle to pay for products that are priced at several times the level of their per capita gross domestic product. In this review, we examine the determinants for increasing drug costs and how Latin American countries face this burgeoning crisis. We emphasize that a number of opportunities and strategies to reduce costs and improve access exist and should be identified and implemented, ideally within a regional approach with multiple stakeholders involved and based on systematic and transparent cost-effectiveness analyses. Cancer 2017;123:1313-1323. © 2016 American Cancer Society. © 2017 American Cancer Society.

Spread-Spectrum Carrier Estimation With Unknown Doppler Shift

NASA Technical Reports Server (NTRS)

DeLeon, Phillip L.; Scaife, Bradley J.

1998-01-01

We present a method for the frequency estimation of a BPSK modulated, spread-spectrum carrier with unknown Doppler shift. The approach relies on a classic periodogram in conjunction with a spectral matched filter. Simulation results indicate accurate carrier estimation with processing gains near 40. A DSP-based prototype has been implemented for real-time carrier estimation for use in New Mexico State University's proposal for NASA's Demand Assignment Multiple Access service.

LEOPACK The integrated services communications system based on LEO satellites

NASA Astrophysics Data System (ADS)

Negoda, A.; Bunin, S.; Bushuev, E.; Dranovsky, V.

LEOPACK is yet another LEO satellite project which provides global integrated services for 'business' communications. It utilizes packet rather then circuit switching in both terrestrial and satellite chains as well as cellular approach for frequencies use. Original multiple access protocols and decentralized network control make it possible to organize regionally or logically independent and world-wide networks. Relatively small number of satellites (28) provides virtually global network coverage.

Quadriphase DS-CDMA wireless communication systems employing the generalized detector

NASA Astrophysics Data System (ADS)

Tuzlukov, Vyacheslav

2012-05-01

Probability of bit-error Per performance of asynchronous direct-sequence code-division multiple-access (DS-CDMA) wireless communication systems employing the generalized detector (GD) constructed based on the generalized approach to signal processing in noise is analyzed. The effects of pulse shaping, quadriphase or direct sequence quadriphase shift keying (DS-QPSK) spreading, aperiodic spreading sequences are considered in DS-CDMA based on GD and compared with the coherent Neyman-Pearson receiver. An exact Per expression and several approximations: one using the characterristic function method, a simplified expression for the improved Gaussian approximation (IGA) and the simplified improved Gaussian approximation are derived. Under conditions typically satisfied in practice and even with a small number of interferers, the standard Gaussian approximation (SGA) for the multiple-access interference component of the GD statistic and Per performance is shown to be accurate. Moreover, the IGA is shown to reduce to the SGA for pulses with zero excess bandwidth. Second, the GD Per performance of quadriphase DS-CDMA is shown to be superior to that of bi-phase DS-CDMA. Numerical examples by Monte Carlo simulation are presented to illustrate the GD Per performance for square-root raised-cosine pulses and spreading factors of moderate to large values. Also, a superiority of GD employment in CDMA systems over the Neyman-Pearson receiver is demonstrated

Interference Cancellation Technique Based on Discovery of Spreading Codes of Interference Signals and Maximum Correlation Detection for DS-CDMA System

NASA Astrophysics Data System (ADS)

Hettiarachchi, Ranga; Yokoyama, Mitsuo; Uehara, Hideyuki

This paper presents a novel interference cancellation (IC) scheme for both synchronous and asynchronous direct-sequence code-division multiple-access (DS-CDMA) wireless channels. In the DS-CDMA system, the multiple access interference (MAI) and the near-far problem (NFP) are the two factors which reduce the capacity of the system. In this paper, we propose a new algorithm that is able to detect all interference signals as an individual MAI signal by maximum correlation detection. It is based on the discovery of all the unknowing spreading codes of the interference signals. Then, all possible MAI patterns so called replicas are generated as a summation of interference signals. And the true MAI pattern is found by taking correlation between the received signal and the replicas. Moreover, the receiver executes MAI cancellation in a successive manner, removing all interference signals by single-stage. Numerical results will show that the proposed IC strategy, which alleviates the detrimental effect of the MAI and the near-far problem, can significantly improve the system performance. Especially, we can obtain almost the same receiving characteristics as in the absense of interference for asynchrnous system when received powers are equal. Also, the same performances can be seen under any received power state for synchronous system.

Lexical access changes in patients with multiple sclerosis: a two-year follow-up study.

PubMed

Sepulcre, Jorge; Peraita, Herminia; Goni, Joaquin; Arrondo, Gonzalo; Martincorena, Inigo; Duque, Beatriz; Velez de Mendizabal, Nieves; Masdeu, Joseph C; Villoslada, Pablo

2011-02-01

The aim of the study was to analyze lexical access strategies in patients with multiple sclerosis (MS) and their changes over time. We studied lexical access strategies during semantic and phonemic verbal fluency tests and also confrontation naming in a 2-year prospective cohort of 45 MS patients and 20 healthy controls. At baseline, switching lexical access strategy (both in semantic and in phonemic verbal fluency tests) and confrontation naming were significantly impaired in MS patients compared with controls. After 2 years follow-up, switching score decreased, and cluster size increased over time in semantic verbal fluency tasks, suggesting a failure in the retrieval of lexical information rather than an impairment of the lexical pool. In conclusion, these findings underline the significant presence of lexical access problems in patients with MS and could point out their key role in the alterations of high-level communications abilities in MS.

Web-based geo-visualisation of spatial information to support evidence-based health policy: a case study of the development process of HealthTracks.

PubMed

Jardine, Andrew; Mullan, Narelle; Gudes, Ori; Cosford, James; Moncrieff, Simon; West, Geoff; Xiao, Jianguo; Yun, Grace; Someford, Peter

Place is of critical importance to health as it can reveal patterns of disease spread and clustering, associations with risk factors, and areas with greatest need for, or least access to healthcare services and promotion activities. Furthermore, in order to get a good understanding of the health status and needs of a particular area a broad range of data are required which can often be difficult and time consuming to obtain and collate. This process has been expedited by bringing together multiple data sources and making them available in an online geo-visualisation, HealthTracks, which consists of a mapping and reporting component. The overall aim of the HealthTracks project is to make spatial health information more accessible to policymakers, analysts, planners and program managers to inform decision-making across the Department of Health Western Australia. Preliminary mapping and reporting applications that have been utilised to inform service planning, increased awareness of the utility of spatial information and improved efficiency in data access were developed. The future for HealthTracks involves expanding the range of data available and developing new analytical capabilities in order to work towards providing external agencies, researchers and eventually the general public access to rich local area spatial data.

A Study of the Seastar Underwater Acoustic Local Area Network Concept

DTIC Science & Technology

2007-12-01

sense multiple access (CSMA) and multiple access with collision avoidance ( MACA ) are reviewed in [19, 22, 23, 34]. Peripheral nodes using ALOHA and...transmissions until the channel is clear. However, the long propagation time limits the effectiveness of CSMA for acoustic communications. MACA [22] uses... MACA protocol, if no ACK message is received after the transmission is completed, the full packet will be retransmitted until reception is

Space-Time Processing for Tactical Mobile Ad Hoc Networks

DTIC Science & Technology

2010-05-01

Spatial Diversity and Imperfect Channel Estimation on Wideband MC- DS - CDMA and MC- CDMA " IEEE Transactions on Communications, Vol. 57, No. 10, pp. 2988...include direct sequence code division multiple access ( DS - CDMA ), Frequency Hopped (FH) CDMA and Orthogonal Frequency Division Multiple Access (OFDMA...capability, LPD/LPI, and operability in non-continuous spectrum. In addition, FH- CDMA is robust to the near-far problem, while DS - CDMA requires

ABSENTEE COMPUTATIONS IN A MULTIPLE-ACCESS COMPUTER SYSTEM.

DTIC Science & Technology

require user interaction, and the user may therefore want to run these computations ’ absentee ’ (or, user not present). A mechanism is presented which...provides for the handling of absentee computations in a multiple-access computer system. The design is intended to be implementation-independent...Some novel features of the system’s design are: a user can switch computations from interactive to absentee (and vice versa), the system can

Parallel Object Activation and Attentional Gating of Information: Evidence from Eye Movements in the Multiple Object Naming Paradigm

ERIC Educational Resources Information Center

Schotter, Elizabeth R.; Ferreira, Victor S.; Rayner, Keith

2013-01-01

Do we access information from any object we can see, or do we access information only from objects that we intend to name? In 3 experiments using a modified multiple object naming paradigm, subjects were required to name several objects in succession when previews appeared briefly and simultaneously in the same location as the target as well as at…

Reduced representation approaches to interrogate genome diversity in large repetitive plant genomes.

PubMed

Hirsch, Cory D; Evans, Joseph; Buell, C Robin; Hirsch, Candice N

2014-07-01

Technology and software improvements in the last decade now provide methodologies to access the genome sequence of not only a single accession, but also multiple accessions of plant species. This provides a means to interrogate species diversity at the genome level. Ample diversity among accessions in a collection of species can be found, including single-nucleotide polymorphisms, insertions and deletions, copy number variation and presence/absence variation. For species with small, non-repetitive rich genomes, re-sequencing of query accessions is robust, highly informative, and economically feasible. However, for species with moderate to large sized repetitive-rich genomes, technical and economic barriers prevent en masse genome re-sequencing of accessions. Multiple approaches to access a focused subset of loci in species with larger genomes have been developed, including reduced representation sequencing, exome capture and transcriptome sequencing. Collectively, these approaches have enabled interrogation of diversity on a genome scale for large plant genomes, including crop species important to worldwide food security. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Multiple-access phased array antenna simulator for a digital beam-forming system investigation

NASA Technical Reports Server (NTRS)

Kerczewski, Robert J.; Yu, John; Walton, Joanne C.; Perl, Thomas D.; Andro, Monty; Alexovich, Robert E.

1992-01-01

Future versions of data relay satellite systems are currently being planned by NASA. Being given consideration for implementation are on-board digital beamforming techniques which will allow multiple users to simultaneously access a single S-band phased array antenna system. To investigate the potential performance of such a system, a laboratory simulator has been developed at NASA's Lewis Research Center. This paper describes the system simulator, and in particular, the requirements, design and performance of a key subsystem, the phased array antenna simulator, which provides realistic inputs to the digital processor including multiple signals, noise, and nonlinearities.

Multiple-access phased array antenna simulator for a digital beam forming system investigation

NASA Technical Reports Server (NTRS)

Kerczewski, Robert J.; Yu, John; Walton, Joanne C.; Perl, Thomas D.; Andro, Monty; Alexovich, Robert E.

1992-01-01

Future versions of data relay satellite systems are currently being planned by NASA. Being given consideration for implementation are on-board digital beamforming techniques which will allow multiple users to simultaneously access a single S-band phased array antenna system. To investigate the potential performance of such a system, a laboratory simulator has been developed at NASA's Lewis Research Center. This paper describes the system simulator, and in particular, the requirements, design, and performance of a key subsystem, the phased array antenna simulator, which provides realistic inputs to the digital processor including multiple signals, noise, and nonlinearities.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gilbert, Jack A.; Quinn, Robert A.; Debelius, Justine

Rapid advances in DNA sequencing, metabolomics, proteomics and computation dramatically increase accessibility of microbiome studies and identify links between the microbiome and disease. Microbial time-series and multiple molecular perspectives enable Microbiome-Wide Association Studies (MWAS), analogous to Genome-Wide Association Studies (GWAS). Rapid research advances point towards actionable results, although approved clinical tests based on MWAS are still in the future. Appreciating the complexity of interactions between diet, chemistry, health and the microbiome, and determining the frequency of observations needed to capture and integrate this dynamic interface, is paramount for addressing the need for personalized and precision microbiome-based diagnostics and therapies.

A convolutional neural network-based screening tool for X-ray serial crystallography.

PubMed

Ke, Tsung Wei; Brewster, Aaron S; Yu, Stella X; Ushizima, Daniela; Yang, Chao; Sauter, Nicholas K

2018-05-01

A new tool is introduced for screening macromolecular X-ray crystallography diffraction images produced at an X-ray free-electron laser light source. Based on a data-driven deep learning approach, the proposed tool executes a convolutional neural network to detect Bragg spots. Automatic image processing algorithms described can enable the classification of large data sets, acquired under realistic conditions consisting of noisy data with experimental artifacts. Outcomes are compared for different data regimes, including samples from multiple instruments and differing amounts of training data for neural network optimization. open access.

Using Registered Dental Hygienists to Promote a School-Based Approach to Dental Public Health

PubMed Central

Wellever, Anthony; Kelly, Patricia

2017-01-01

We examine a strategy for improving oral health in the United States by focusing on low-income children in school-based settings. Vulnerable children often experience cultural, social, economic, structural, and geographic barriers when trying to access dental services in traditional dental office settings. These disparities have been discussed for more than a decade in multiple US Department of Health and Human Services publications. One solution is to revise dental practice acts to allow registered dental hygienists increased scope of services, expanded public health delivery opportunities, and decreased dentist supervision. We provide examples of how federally qualified health centers have implemented successful school-based dental models within the parameters of two state policies that allow registered dental hygienists varying levels of dentist supervision. Changes to dental practice acts at the state level allowing registered dental hygienists to practice with limited supervision in community settings, such as schools, may provide vulnerable populations greater access to screening and preventive services. We derive our recommendations from expert opinion. PMID:28661808

Mobile Technology Use by People Experiencing Multiple Sclerosis Fatigue: Survey Methodology.

PubMed

Van Kessel, Kirsten; Babbage, Duncan R; Reay, Nicholas; Miner-Williams, Warren M; Kersten, Paula

2017-02-28

Fatigue is one of the most commonly reported symptoms of multiple sclerosis (MS). It has a profound impact on all spheres of life, for people with MS and their relatives. It is one of the key precipitants of early retirement. Individual, group, and Internet cognitive behavioral therapy-based approaches to supporting people with MS to manage their fatigue have been shown to be effective. The aim of this project was to (1) survey the types of mobile devices and level of Internet access people with MS use or would consider using for a health intervention and (2) characterize the levels of fatigue severity and their impact experienced by the people in our sample to provide an estimate of fatigue severity of people with MS in New Zealand. The ultimate goal of this work was to support the future development of a mobile intervention for the management of fatigue for people with MS. Survey methodology using an online questionnaire was used to assess people with MS. A total of 51 people with MS participated. The average age was 48.5 years, and the large majority of the sample (77%) was female. Participants reported significant levels of fatigue as measured with the summary score of the Neurological Fatigue Index (mean 31.4 [SD 5.3]). Most (84%) respondents scored on average more than 3 on the fatigue severity questions, reflecting significant fatigue. Mobile phone usage was high with 86% of respondents reporting having a mobile phone; apps were used by 75% of respondents. Most participants (92%) accessed the Internet from home. New Zealand respondents with MS experienced high levels of both fatigue severity and fatigue impact. The majority of participants have a mobile device and access to the Internet. These findings, along with limited access to face-to-face cognitive behavioral therapy-based interventions, create an opportunity to develop a mobile technology platform for delivering a cognitive behavioral therapy-based intervention to decrease the severity and impact of fatigue in people with MS. ©Kirsten Van Kessel, Duncan R Babbage, Nicholas Reay, Warren M Miner-Williams, Paula Kersten. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 28.02.2017.

Mobile Technology Use by People Experiencing Multiple Sclerosis Fatigue: Survey Methodology

PubMed Central

Reay, Nicholas

2017-01-01

Background Fatigue is one of the most commonly reported symptoms of multiple sclerosis (MS). It has a profound impact on all spheres of life, for people with MS and their relatives. It is one of the key precipitants of early retirement. Individual, group, and Internet cognitive behavioral therapy–based approaches to supporting people with MS to manage their fatigue have been shown to be effective. Objective The aim of this project was to (1) survey the types of mobile devices and level of Internet access people with MS use or would consider using for a health intervention and (2) characterize the levels of fatigue severity and their impact experienced by the people in our sample to provide an estimate of fatigue severity of people with MS in New Zealand. The ultimate goal of this work was to support the future development of a mobile intervention for the management of fatigue for people with MS. Methods Survey methodology using an online questionnaire was used to assess people with MS. A total of 51 people with MS participated. The average age was 48.5 years, and the large majority of the sample (77%) was female. Results Participants reported significant levels of fatigue as measured with the summary score of the Neurological Fatigue Index (mean 31.4 [SD 5.3]). Most (84%) respondents scored on average more than 3 on the fatigue severity questions, reflecting significant fatigue. Mobile phone usage was high with 86% of respondents reporting having a mobile phone; apps were used by 75% of respondents. Most participants (92%) accessed the Internet from home. Conclusions New Zealand respondents with MS experienced high levels of both fatigue severity and fatigue impact. The majority of participants have a mobile device and access to the Internet. These findings, along with limited access to face-to-face cognitive behavioral therapy–based interventions, create an opportunity to develop a mobile technology platform for delivering a cognitive behavioral therapy–based intervention to decrease the severity and impact of fatigue in people with MS. PMID:28246073

Orthogonal Chirp-Based Ultrasonic Positioning

PubMed Central

Khyam, Mohammad Omar; Ge, Shuzhi Sam; Li, Xinde; Pickering, Mark

2017-01-01

This paper presents a chirp based ultrasonic positioning system (UPS) using orthogonal chirp waveforms. In the proposed method, multiple transmitters can simultaneously transmit chirp signals, as a result, it can efficiently utilize the entire available frequency spectrum. The fundamental idea behind the proposed multiple access scheme is to utilize the oversampling methodology of orthogonal frequency-division multiplexing (OFDM) modulation and orthogonality of the discrete frequency components of a chirp waveform. In addition, the proposed orthogonal chirp waveforms also have all the advantages of a classical chirp waveform. Firstly, the performance of the waveforms is investigated through correlation analysis and then, in an indoor environment, evaluated through simulations and experiments for ultrasonic (US) positioning. For an operational range of approximately 1000 mm, the positioning root-mean-square-errors (RMSEs) &90% error were 4.54 mm and 6.68 mm respectively. PMID:28448454

Orthogonal Chirp-Based Ultrasonic Positioning.

PubMed

Khyam, Mohammad Omar; Ge, Shuzhi Sam; Li, Xinde; Pickering, Mark

2017-04-27

This paper presents a chirp based ultrasonic positioning system (UPS) using orthogonal chirp waveforms. In the proposed method, multiple transmitters can simultaneously transmit chirp signals, as a result, it can efficiently utilize the entire available frequency spectrum. The fundamental idea behind the proposed multiple access scheme is to utilize the oversampling methodology of orthogonal frequency-division multiplexing (OFDM) modulation and orthogonality of the discrete frequency components of a chirp waveform. In addition, the proposed orthogonal chirp waveforms also have all the advantages of a classical chirp waveform. Firstly, the performance of the waveforms is investigated through correlation analysis and then, in an indoor environment, evaluated through simulations and experiments for ultrasonic (US) positioning. For an operational range of approximately 1000 mm, the positioning root-mean-square-errors (RMSEs) &90% error were 4.54 mm and 6.68 mm respectively.

Impact of MAC Delay on AUV Localization: Underwater Localization Based on Hyperbolic Frequency Modulation Signal

PubMed Central

2018-01-01

Medium Access Control (MAC) delay which occurs between the anchor node’s transmissions is one of the error sources in underwater localization. In particular, in AUV localization, the MAC delay significantly degrades the ranging accuracy. The Cramer-Rao Low Bound (CRLB) definition theoretically proves that the MAC delay significantly degrades the localization performance. This paper proposes underwater localization combined with multiple access technology to decouple the localization performance from the MAC delay. Towards this goal, we adopt hyperbolic frequency modulation (HFM) signal that provides multiplexing based on its good property, high-temporal correlation. Owing to the multiplexing ability of the HFM signal, the anchor nodes can transmit packets without MAC delay, i.e., simultaneous transmission is possible. In addition, the simulation results show that the simultaneous transmission is not an optional communication scheme, but essential for the localization of mobile object in underwater. PMID:29373518

Impact of MAC Delay on AUV Localization: Underwater Localization Based on Hyperbolic Frequency Modulation Signal.

PubMed

Kim, Sungryul; Yoo, Younghwan

2018-01-26

Medium Access Control (MAC) delay which occurs between the anchor node's transmissions is one of the error sources in underwater localization. In particular, in AUV localization, the MAC delay significantly degrades the ranging accuracy. The Cramer-Rao Low Bound (CRLB) definition theoretically proves that the MAC delay significantly degrades the localization performance. This paper proposes underwater localization combined with multiple access technology to decouple the localization performance from the MAC delay. Towards this goal, we adopt hyperbolic frequency modulation (HFM) signal that provides multiplexing based on its good property, high-temporal correlation. Owing to the multiplexing ability of the HFM signal, the anchor nodes can transmit packets without MAC delay, i.e., simultaneous transmission is possible. In addition, the simulation results show that the simultaneous transmission is not an optional communication scheme, but essential for the localization of mobile object in underwater.

A Multi-Discipline, Multi-Genre Digital Library for Research and Education

NASA Technical Reports Server (NTRS)

Nelson, Michael L.; Maly, Kurt; Shen, Stewart N. T.

2004-01-01

We describe NCSTRL+, a unified, canonical digital library for educational and scientific and technical information (STI). NCSTRL+ is based on the Networked Computer Science Technical Report Library (NCSTRL), a World Wide Web (WWW) accessible digital library (DL) that provides access to over 100 university departments and laboratories. NCSTRL+ implements two new technologies: cluster functionality and publishing "buckets". We have extended the Dienst protocol, the protocol underlying NCSTRL, to provide the ability to "cluster" independent collections into a logically centralized digital library based upon subject category classification, type of organization, and genres of material. The concept of "buckets" provides a mechanism for publishing and managing logically linked entities with multiple data formats. The NCSTRL+ prototype DL contains the holdings of NCSTRL and the NASA Technical Report Server (NTRS). The prototype demonstrates the feasibility of publishing into a multi-cluster DL, searching across clusters, and storing and presenting buckets of information.

NCSTRL+: Adding Multi-Discipline and Multi-Genre Support to the Dienst Protocol Using Clusters and Buckets

NASA Technical Reports Server (NTRS)

Nelson, Michael L.; Maly, Kurt; Shen, Stewart N. T.; Zubair, Mohammad

1998-01-01

We describe NCSTRL+, a unified, canonical digital library for scientific and technical information (STI). NCSTRL+ is based on the Networked Computer Science Technical Report Library (NCSTRL), a World Wide Web (WWW) accessible digital library (DL) that provides access to over 100 university departments and laboratories. NCSTRL+ implements two new technologies: cluster functionality and publishing buckets. We have extended Dienst, the protocol underlying NCSTRL, to provide the ability to cluster independent collections into a logically centralized digital library based upon subject category classification, type of organization, and genres of material. The bucket construct provides a mechanism for publishing and managing logically linked entities with multiple data forms as a single object. The NCSTRL+ prototype DL contains the holdings of NCSTRL and the NASA Technical Report Server (NTRS). The prototype demonstrates the feasibility of publishing into a multi-cluster DL, searching across clusters, and storing and presenting buckets of information.

Early childhood caries in Indigenous communities

PubMed Central

Irvine, JD; Holve, S; Krol, D; Schroth, R

2011-01-01

The oral health of Indigenous children of Canada (First Nations, Inuit and Métis) and the United States (American Indian and Alaska Native) is a major child health issue. This is exemplified by the high prevalence of early childhood caries (ECC) with resulting adverse health effects, as well as high rates and costs of restorative and surgical treatments under general anesthesia. ECC is an infectious disease that is influenced by multiple factors, including socioeconomic determinants, and requires a combination of approaches for improvement. The present statement includes recommendations for oral health preventive and clinical care for young infants and pregnant women by primary health care providers, community-based health promotion initiatives, oral health workforce and access issues, and advocacy for community water fluoridation and fluoride varnish program access. Further community-based research on the epidemiology, prevention, management and microbiology of ECC in Indigenous communities would be beneficial. PMID:22654547

Early childhood caries in indigenous communities.

PubMed

2011-06-01

The oral health of Indigenous children of Canada (First Nations, Inuit, and Métis) and the United States (American Indian, Alaska Native) is a major child health issue: there is a high prevalence of early childhood caries (ECC) and resulting adverse health effects in this community, as well as high rates and costs of restorative and surgical treatments under general anesthesia. ECC is an infectious disease that is influenced by multiple factors, including socioeconomic determinants, and requires a combination of approaches for improvement. This statement includes recommendations for preventive oral health and clinical care for young infants and pregnant women by primary health care providers, community-based health-promotion initiatives, oral health workforce and access issues, and advocacy for community water fluoridation and fluoride-varnish program access. Further community-based research on the epidemiology, prevention, management, and microbiology of ECC in Indigenous communities would be beneficial.

Early childhood caries in Indigenous communities: A joint statement with the American Academy of Pediatrics.

PubMed

Irvine, Jd; Holve, S; Krol, D; Schroth, R

2011-06-01

The oral health of Indigenous children of Canada (First Nations, Inuit and Métis) and the United States (American Indian and Alaska Native) is a major child health issue. This is exemplified by the high prevalence of early childhood caries (ECC) with resulting adverse health effects, as well as high rates and costs of restorative and surgical treatments under general anesthesia. ECC is an infectious disease that is influenced by multiple factors, including socioeconomic determinants, and requires a combination of approaches for improvement. The present statement includes recommendations for oral health preventive and clinical care for young infants and pregnant women by primary health care providers, community-based health promotion initiatives, oral health workforce and access issues, and advocacy for community water fluoridation and fluoride varnish program access. Further community-based research on the epidemiology, prevention, management and microbiology of ECC in Indigenous communities would be beneficial.

Structure for common access and support of fuel cell stacks

DOEpatents

Walsh, Michael M.

2000-01-01

A structure provides common support and access to multiple fuel cells externally mounted thereto. The structure has openings leading to passages defined therein for providing the access. Various other fuel cell power system components are connected at the openings, such as reactant and coolant sources.

Teaching Individuals with Profound Multiple Disabilities to Access Preferred Stimuli with Multiple Microswitches

ERIC Educational Resources Information Center

Tam, Gee May; Phillips, Katrina J.; Mudford, Oliver C.

2011-01-01

We replicated and extended previous research on microswitch facilitated choice making by individuals with profound multiple disabilities. Following an assessment of stimulus preferences, we taught 6 adults with profound multiple disabilities to emit 2 different responses to activate highly preferred stimuli. All participants learnt to activate…

Characterization of molecular diversity and genome-wide mapping of loci associated with resistance to stripe rust and stem rust in Ethiopian bread wheat accessions.

PubMed

Muleta, Kebede T; Rouse, Matthew N; Rynearson, Sheri; Chen, Xianming; Buta, Bedada G; Pumphrey, Michael O

2017-08-04

The narrow genetic basis of resistance in modern wheat cultivars and the strong selection response of pathogen populations have been responsible for periodic and devastating epidemics of the wheat rust diseases. Characterizing new sources of resistance and incorporating multiple genes into elite cultivars is the most widely accepted current mechanism to achieve durable varietal performance against changes in pathogen virulence. Here, we report a high-density molecular characterization and genome-wide association study (GWAS) of stripe rust and stem rust resistance in 190 Ethiopian bread wheat lines based on phenotypic data from multi-environment field trials and seedling resistance screening experiments. A total of 24,281 single nucleotide polymorphism (SNP) markers filtered from the wheat 90 K iSelect genotyping assay was used to survey Ethiopian germplasm for population structure, genetic diversity and marker-trait associations. Upon screening for field resistance to stripe rust in the Pacific Northwest of the United States and Ethiopia over multiple growing seasons, and against multiple races of stripe rust and stem rust at seedling stage, eight accessions displayed resistance to all tested races of stem rust and field resistance to stripe rust in all environments. Our GWAS results show 15 loci were significantly associated with seedling and adult plant resistance to stripe rust at false discovery rate (FDR)-adjusted probability (P) <0.10. GWAS also detected 9 additional genomic regions significantly associated (FDR-adjusted P < 0.10) with seedling resistance to stem rust in the Ethiopian wheat accessions. Many of the identified resistance loci were mapped close to previously identified rust resistance genes; however, three loci on the short arms of chromosomes 5A and 7B for stripe rust resistance and two on chromosomes 3B and 7B for stem rust resistance may be novel. Our results demonstrate that considerable genetic variation resides within the landrace accessions that can be utilized to broaden the genetic base of rust resistance in wheat breeding germplasm. The molecular markers identified in this study should be useful in efficiently targeting the associated resistance loci in marker-assisted breeding for rust resistance in Ethiopia and other countries.

Technological Innovations for High-Throughput Approaches to In Vitro Allergy Diagnosis.

PubMed

Chapman, Martin D; Wuenschmann, Sabina; King, Eva; Pomés, Anna

2015-07-01

Allergy diagnostics is being transformed by the advent of in vitro IgE testing using purified allergen molecules, combined with multiplex technology and biosensors, to deliver discriminating, sensitive, and high-throughput molecular diagnostics at the point of care. Essential elements of IgE molecular diagnostics are purified natural or recombinant allergens with defined purity and IgE reactivity, planar or bead-based multiplex systems to enable IgE to multiple allergens to be measured simultaneously, and, most recently, nanotechnology-based biosensors that facilitate rapid reaction rates and delivery of test results via mobile devices. Molecular diagnostics relies on measurement of IgE to purified allergens, the "active ingredients" of allergenic extracts. Typically, this involves measuring IgE to multiple allergens which is facilitated by multiplex technology and biosensors. The technology differentiates between clinically significant cross-reactive allergens (which could not be deduced by conventional IgE assays using allergenic extracts) and provides better diagnostic outcomes. Purified allergens are manufactured under good laboratory practice and validated using protein chemistry, mass spectrometry, and IgE antibody binding. Recently, multiple allergens (from dog) were expressed as a single molecule with high diagnostic efficacy. Challenges faced by molecular allergy diagnostic companies include generation of large panels of purified allergens with known diagnostic efficacy, access to flexible and robust array or sensor technology, and, importantly, access to well-defined serum panels form allergic patients for product development and validation. Innovations in IgE molecular diagnostics are rapidly being brought to market and will strengthen allergy testing at the point of care.

A Complete Image Management and Communications Network for the Neuroradiology Service at Georgetown University Hospital

NASA Astrophysics Data System (ADS)

Horii, Steven C.; Muraki, Alan; Mallon-Ingeholm, Mary L.; Mun, Seong K.; Clark, Letitia; Schellinger, Dieter

1989-05-01

A complete image management and communications system has been installed at Georgetown University Hospital (GUH). The network is based on the A T & T CommView System. In the Neuroradiology Division, this comprehensive network supports a multiscreen workstation with access to multiple imaging modalities such as CT and MRI from both the hospital and a remote imaging center. In addition, the radiologist can access these images from various workstations located throughout the hospital as well as from remote sites such as the home. Among the radiology services supported by the network, neuroradiology has the greatest need for such a system with extensive daily requirements involving the remote imaging center and on-line consultation around the clock. By providing neuroradiology with all available communication links, the radiologist can monitor, diagnose, and consult. The remote site has a subsystem capable of acquiring images and transmitting them over a high speed T1 data circuit. The GUH neuroradiologist can view these images on the neuro workstation or any of the workstations available in the Hospital. Fast and easy access to the images allows a radiologist to monitor multiple examinations as well as to utilize the workstation for diagnosis. To provide the neuroradiologist quick access to images at all times, a PC-based Results Viewing Station (RVS) has been placed in a doctor's home. Images may be sent to the RVS, or the user may request images from the central database at the hospital. Images can be viewed at home either as they are transmitted, or following transfer of a whole study. The efficiency and effectiveness of the system's capabilities with special regard to remote and teleradiology (RVS) operations have been studied for the neuroradiology service. This paper will discuss the current clinical acceptance and use, problems in implementation, and ways these difficulties are being surmounted.

Policies and Programs to Facilitate Access to Targeted Cancer Therapies in Thailand

PubMed Central

Sruamsiri, Rosarin; Ross-Degnan, Dennis; Lu, Christine Y.; Chaiyakunapruk, Nathorn; Wagner, Anita K.

2015-01-01

Background Increasing access to clinically beneficial targeted cancer medicines is a challenge in every country due to their high cost. We describe the interplay of innovative policies and programs involving multiple stakeholders to facilitate access to these medicines in Thailand, as well as the utilization of selected targeted therapies over time. Methods We selected two medicines on the 2013 Thai national list of essential medicines (NLEM) [letrozole and imatinib] and three unlisted medicines for the same indications [trastuzumab, nilotinib and dasatinib]. We created timelines of access policies and programs for these products based on scientific and grey literature. Using IMS Health sales data, we described the trajectories of sales volumes of the study medicines between January 2001 and December 2012. We compared estimated average numbers of patients treated before and after the implementation of policies and programs for each product. Results Different stakeholders implemented multiple interventions to increase access to the study medicines for different patient populations. During 2007–2009, the Thai Government created a special NLEM category with different coverage requirements for payers and issued compulsory licenses; payers negotiated prices with manufacturers and engaged in pooled procurement; pharmaceutical companies expanded patient assistance programs and lowered prices in different ways. Compared to before the interventions, estimated numbers of patients treated with each medicine increased significantly afterwards: for letrozole from 645 (95% CI 366–923) to 3683 (95% CI 2,748–4,618); for imatinib from 103 (95% CI 72–174) to 350 (95% CI 307–398); and for trastuzumab from 68 (95% CI 45–118) to 412 (95% CI 344–563). Conclusions Government, payers, and manufacturers implemented multi-pronged approaches to facilitate access to targeted cancer therapies for the Thai population, which differed by medicine. Routine monitoring is needed to assess clinical and economic impacts of these strategies in the health system. PMID:25798948

A quality improvement project to reduce the intraoperative use of single-dose fentanyl vials across multiple patients in a pediatric institution.

PubMed

Buck, David; Subramanyam, Rajeev; Varughese, Anna

2016-01-01

The use of a single-dose vial across multiple patients presents a risk to sterility and is against CDC guidelines. We initiated a quality improvement (QI) project to reduce the intraoperative use of single-dose vials of fentanyl across multiple patients at Cincinnati Children's Hospital Medical Center (CCHMC). The initial step of the improvement project was the development of a Key Driver Diagram. The diagram has the SMART aim of the project, key drivers inherent to the process we are trying to improve, and specific interventions targeting the key drivers. The number of patients each week receiving an IV dose of fentanyl, from a vial previously accessed for another patient was tracked in a high turnover operating room (OR). The improvement model used was based on the concept of building Plan-Do-Study-Act (PDSA) cycles. Tests of change included provider education, provision of an increased number of fentanyl vials, alternate wasting processes, and provision of single-use fentanyl syringes by the pharmacy. Prior to initiation of this project, it was common for a single fentanyl vial to be accessed for multiple patients. Our data showed an average percentage of failures of just over 50%. During the end of the project, after 7 months, the mean percentage failures had dropped to 5%. Preparation of 20 mcg single-use fentanyl syringes by pharmacy, combined with education of providers on appropriate use, was successful in reducing failures to below our goal of 25%. Appropriately sized fentanyl syringes prepared by pharmacy, education on correct use of single-dose vials, and reminders in the OR, reduced the percentage of patients receiving a dose of fentanyl from a vial previously accessed for another patient in a high-volume otolaryngology room. © 2015 John Wiley & Sons Ltd.

Factors associated with choice of web or print intervention materials in the healthy directions 2 study.

PubMed

Greaney, Mary L; Puleo, Elaine; Bennett, Gary G; Haines, Jess; Viswanath, K; Gillman, Matthew W; Sprunck-Harrild, Kim; Coeling, Molly; Rusinak, Donna; Emmons, Karen M

2014-02-01

Many U.S. adults have multiple behavioral risk factors, and effective, scalable interventions are needed to promote population-level health. In the health care setting, interventions are often provided in print, although accessible to nearly everyone, are brief (e.g., pamphlets), are not interactive, and can require some logistics around distribution. Web-based interventions offer more interactivity but may not be accessible to all. Healthy Directions 2 was a primary care-based cluster randomized controlled trial designed to improve five behavioral cancer risk factors among a diverse sample of adults (n = 2,440) in metropolitan Boston. Intervention materials were available via print or the web. Purpose. To (a) describe the Healthy Directions 2 study design and (b) identify baseline factors associated with whether participants opted for print or web-based materials. Hierarchical regression models corrected for clustering by physician were built to examine factors associated with choice of intervention modality. At baseline, just 4.0% of participants met all behavioral recommendations. Nearly equivalent numbers of intervention participants opted for print and web-based materials (44.6% vs. 55.4%). Participants choosing web-based materials were younger, and reported having a better financial status, better perceived health, greater computer comfort, and more frequent Internet use (p < .05) than those opting for print. In addition, Whites were more likely to pick web-based material than Black participants. Interventions addressing multiple behaviors are needed in the primary care setting, but they should be available in web and print formats as nearly equal number of participants chose each option, and there are significant differences in the population groups using each modality.

Interference-Assisted Techniques for Transmission and Multiple Access in Optical Communications

NASA Astrophysics Data System (ADS)

Guan, Xun

Optical communications can be in wired or wireless form. Fiber optics communication (FOC) connects transmitters and receivers with optical fiber. Benefiting from its high bandwidth, low cost per volume and stability, it gains a significant market share in long-haul networks, access networks and data centers. Meanwhile, optical wireless communication (OWC) is also emerging as a crucial player in the communication market. In OWC, free-space optical communication (FSO) and visible light communication (VLC) are being studied and commercially deployed extensively. Interference is a common phenomenon in multi-user communication systems. In both FOC and OWC, interference has long been treated as a detrimental effect. However, it could also be beneficial to system applications. The effort of harnessing interference has spurred numerous innovations. Interesting examples are physical-layer network coding (PNC) and non-orthogonal multiple access (NOMA). The first part of this thesis in on the topic of PNC. PNC was firstly proposed in wireless communication to improve the throughput of a two-way relay network (TWRN). As a variation of network coding (NC), PNC turns the common channel interference (CCI) as a natural network coding operation. In this thesis, PNC is introduced into optical communication. Three schemes are proposed in different scenarios. Firstly, PNC is applied to a coherent optical orthogonal frequency division multiplexing (CO-OFDM) system so as to improve the throughput of the multicast network. The optical signal to noise ratio (OSNR) penalty is quite low. Secondly, we investigate the application of PNC in an OFDM passive optical network (OFDM-PON) supporting heterogeneous services. It is found that only minor receiver power penalties are observed to realize PNC-based virtual private networks (VPN), both in the wired service part and the wireless service part in an OFDM-PON with heterogeneous services. Thirdly, we innovate relay-based visible light communication (VLC) by adopting PNC, with a newly proposed phase-aligning method. PNC could improve the throughput at the bottlenecking relay node in a VLC system, and the proposed phase aligning method can improve the BER performance. The second part of this thesis discusses another interference-assisted technology in communication, that is, non-orthogonal multiple access (NOMA). NOMA multiplexes signals from multiple users in another dimension: power domain, with a non-orthogonal multiplexing in other dimensions such as time, frequency and code. Three schemes are proposed in this part. The first and the second schemes both realize NOMA in VLC, with different multiuser detection (MUD) techniques and a proposed phase pre-distortion method. Although both can decrease the system BER compared to conventional NOMA, the scheme using joint detection (JD) outperforms the one using successive interference cancellation (SIC). The third scheme investigated in this part is a combination of NOMA and a multicarrier precoding (MP) technology based on an orthogonal circulant transform matrix (OCT). This combination can avoid the complicated adaptive bit loading or electronic equalization, making NOMA more attractive in a practical system.

MFAM: Multiple Frequency Adaptive Model-Based Indoor Localization Method.

PubMed

Tuta, Jure; Juric, Matjaz B

2018-03-24

This paper presents MFAM (Multiple Frequency Adaptive Model-based localization method), a novel model-based indoor localization method that is capable of using multiple wireless signal frequencies simultaneously. It utilizes indoor architectural model and physical properties of wireless signal propagation through objects and space. The motivation for developing multiple frequency localization method lies in the future Wi-Fi standards (e.g., 802.11ah) and the growing number of various wireless signals present in the buildings (e.g., Wi-Fi, Bluetooth, ZigBee, etc.). Current indoor localization methods mostly rely on a single wireless signal type and often require many devices to achieve the necessary accuracy. MFAM utilizes multiple wireless signal types and improves the localization accuracy over the usage of a single frequency. It continuously monitors signal propagation through space and adapts the model according to the changes indoors. Using multiple signal sources lowers the required number of access points for a specific signal type while utilizing signals, already present in the indoors. Due to the unavailability of the 802.11ah hardware, we have evaluated proposed method with similar signals; we have used 2.4 GHz Wi-Fi and 868 MHz HomeMatic home automation signals. We have performed the evaluation in a modern two-bedroom apartment and measured mean localization error 2.0 to 2.3 m and median error of 2.0 to 2.2 m. Based on our evaluation results, using two different signals improves the localization accuracy by 18% in comparison to 2.4 GHz Wi-Fi-only approach. Additional signals would improve the accuracy even further. We have shown that MFAM provides better accuracy than competing methods, while having several advantages for real-world usage.

MFAM: Multiple Frequency Adaptive Model-Based Indoor Localization Method

PubMed Central

Juric, Matjaz B.

2018-01-01

This paper presents MFAM (Multiple Frequency Adaptive Model-based localization method), a novel model-based indoor localization method that is capable of using multiple wireless signal frequencies simultaneously. It utilizes indoor architectural model and physical properties of wireless signal propagation through objects and space. The motivation for developing multiple frequency localization method lies in the future Wi-Fi standards (e.g., 802.11ah) and the growing number of various wireless signals present in the buildings (e.g., Wi-Fi, Bluetooth, ZigBee, etc.). Current indoor localization methods mostly rely on a single wireless signal type and often require many devices to achieve the necessary accuracy. MFAM utilizes multiple wireless signal types and improves the localization accuracy over the usage of a single frequency. It continuously monitors signal propagation through space and adapts the model according to the changes indoors. Using multiple signal sources lowers the required number of access points for a specific signal type while utilizing signals, already present in the indoors. Due to the unavailability of the 802.11ah hardware, we have evaluated proposed method with similar signals; we have used 2.4 GHz Wi-Fi and 868 MHz HomeMatic home automation signals. We have performed the evaluation in a modern two-bedroom apartment and measured mean localization error 2.0 to 2.3 m and median error of 2.0 to 2.2 m. Based on our evaluation results, using two different signals improves the localization accuracy by 18% in comparison to 2.4 GHz Wi-Fi-only approach. Additional signals would improve the accuracy even further. We have shown that MFAM provides better accuracy than competing methods, while having several advantages for real-world usage. PMID:29587352

A New Subcarrier Allocation Strategy for MIMO-OFDMA Multicellular Networks Based on Cooperative Interference Mitigation

PubMed Central

Gkonis, Panagiotis K.; Seimeni, Maria A.; Asimakis, Nikolaos P.; Kaklamani, Dimitra I.; Venieris, Iakovos S.

2014-01-01

The goal of the study presented in this paper is to investigate the performance of a new subcarrier allocation strategy for Orthogonal Frequency Division Multiple Access (OFDMA) multicellular networks which employ Multiple Input Multiple Output (MIMO) architecture. For this reason, a hybrid system-link level simulator has been developed executing independent Monte Carlo (MC) simulations in parallel. Up to two tiers of cells around the central cell are taken into consideration and increased loading per cell. The derived results indicate that this strategy can provide up to 12% capacity gain for 16-QAM modulation and two tiers of cells around the central cell in a symmetric 2 × 2 MIMO configuration. This gain is derived when comparing the proposed strategy to the traditional approach of allocating subcarriers that maximize only the desired user's signal. PMID:24683351

Shifting from the single- to the multitarget paradigm in drug discovery

PubMed Central

Medina-Franco, José L.; Giulianotti, Marc A.; Welmaker, Gregory S.; Houghten, Richard A.

2013-01-01

Increasing evidence that several drug compounds exert their effects through interactions with multiple targets is boosting the development of research fields that challenge the data reductionism approach. In this article, we review and discuss the concepts of drug repurposing, polypharmacology, chemogenomics, phenotypic screening and highthroughput in vivo testing of mixture-based libraries in an integrated manner. These research fields offer alternatives to the current paradigm of drug discovery, from a one target–one drug model to a multiple-target approach. Furthermore, the goals of lead identification are being expanded accordingly to identify not only ‘key’ compounds that fit with a single-target ‘lock’, but also ‘master key’ compounds that favorably interact with multiple targets (i.e. operate a set of desired locks to gain access to the expected clinical effects). PMID:23340113

Prevalence of difficult venous access and associated risk factors in highly complex hospitalised patients.

PubMed

Armenteros-Yeguas, Victoria; Gárate-Echenique, Lucía; Tomás-López, Maria Aranzazu; Cristóbal-Domínguez, Estíbaliz; Moreno-de Gusmão, Breno; Miranda-Serrano, Erika; Moraza-Dulanto, Maria Inmaculada

2017-12-01

To estimate the prevalence of difficult venous access in complex patients with multimorbidity and to identify associated risk factors. In highly complex patients, factors like ageing, the need for frequent use of irritant medication and multiple venous catheterisations to complete treatment could contribute to exhaustion of venous access. A cross-sectional study was conducted. 'Highly complex' patients (n = 135) were recruited from March 2013-November 2013. The main study variable was the prevalence of difficult venous access, assessed using one of the following criteria: (1) a history of difficulties obtaining venous access based on more than two attempts to insert an intravenous line and (2) no visible or palpable veins. Other factors potentially associated with the risk of difficult access were also measured (age, gender and chronic illnesses). Univariate analysis was performed for each potential risk factor. Factors with p < 0·2 were then included in multivariable logistic regression analysis. Odds ratios were also calculated. The prevalence of difficult venous access was 59·3%. The univariate logistic regression analysis indicated that gender, a history of vascular access complications and osteoarticular disease were significantly associated with difficult venous access. The multivariable logistic regression showed that only gender was an independent risk factor and the odds ratios was 2·85. The prevalence of difficult venous access is high in this population. Gender (female) is the only independent risk factor associated with this. Previous history of several attempts at catheter insertion is an important criterion in the assessment of difficult venous access. The prevalence of difficult venous access in complex patients is 59·3%. Significant risk factors include being female and a history of complications related to vascular access. © 2017 John Wiley & Sons Ltd.

Case Study in Modeling Accessibility for Online Instruction

ERIC Educational Resources Information Center

Conway, Thomas Hayes

2017-01-01

The purpose of this qualitative multiple case study was to explore how accessibility standards are adapted to create online learning environments that are accessible to people who use assistive technology, or have navigational challenges due to physical or intellectual disabilities. Rogers diffusion of innovation was used as the contextual…

Identity and Access Management: Technological Implementation of Policy

ERIC Educational Resources Information Center

von Munkwitz-Smith, Jeff; West, Ann

2004-01-01

Navigating the multiple processes for accessing ever-multiplying campus information systems can be a daunting task for students, faculty, and staff. This article provides a brief overview of Identity and Access Management Services. The authors review key characteristics and components of this new information architecture and address the issue of…

Study of optoelectronic switch for satellite-switched time-division multiple access

NASA Technical Reports Server (NTRS)

Su, Shing-Fong; Jou, Liz; Lenart, Joe

1987-01-01

The use of optoelectronic switching for satellite switched time division multiple access will improve the isolation and reduce the crosstalk of an IF switch matrix. The results are presented of a study on optoelectronic switching. Tasks include literature search, system requirements study, candidate switching architecture analysis, and switch model optimization. The results show that the power divided and crossbar switching architectures are good candidates for an IF switch matrix.

MCNP6 Fission Multiplicity with FMULT Card

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilcox, Trevor; Fensin, Michael Lorne; Hendricks, John S.

With the merger of MCNPX and MCNP5 into MCNP6, MCNP6 now provides all the capabilities of both codes allowing the user to access all the fission multiplicity data sets. Detailed in this paper is: (1) the new FMULT card capabilities for accessing these different data sets; (2) benchmark calculations, as compared to experiment, detailing the results of selecting these separate data sets for thermal neutron induced fission on U-235.

Maritime Analytics Prototype: Final Development Report

DTIC Science & Technology

2014-04-01

access management platform OpenAM , support for multiple instances of the same type of widget and support for installation specific configuration files to...et de la gestion de l’accès OpenAM , le support pour plusieurs instances du même type de widget et le support des fichiers d’installation de...open source authentication and access management platform OpenAM , support for multiple instances of the same type of widget and support for

On the performance of a code division multiple access scheme with transmit/receive conflicts

NASA Astrophysics Data System (ADS)

Silvester, J. A.

One of the benefits of spread spectrum is that by assigning each user a different orthogonal signal set, multiple transmissions can occur simultaneously. This possibility is utilized in new access schemes called Code Division Multiple Access (CDMA). The present investigation is concerned with a particular CDMA implementation in which the transmit times for each symbol are exactly determined in a distributed manner such that both sender and receiver know them. In connection with a decision whether to transmit or receive, the loss of a symbol in one of the channels results. The system employs thus a coding technique which permits correct decoding of a codeword even if some constituent symbols are missing or in error. The technique used is Reed Solomon coding. The performance of this system is analyzed, and attention is given to the optimum strategy which should be used in deciding whether to receive or transmit.

Improving the secrecy rate by turning foes to allies: An auction scheme

NASA Astrophysics Data System (ADS)

Ma, Ya-Yan; Wang, Bao-Yun

2015-09-01

Security against eavesdroppers is a critical issue in cognitive radio networks (CRNs). In this paper, a scenario consisting of one primary pair and multiple secondary pairs is considered. The secondary transmitters (STs) work in half-duplex mode and they are potential eavesdroppers on the primary transmission unless they are allowed to simultaneously transmit with the primary transmitter (PT). A modified second-price sealed-bid auction scheme is employed to model the interaction between the PT and STs. With the proposed auction scheme, the hostile relationship between the PT and STs is transformed into a cooperative relationship. An iterative algorithm based on the max-min criteria is proposed to find the optimal bidding power of the STs for an access chance in the presence of multiple eavesdroppers. Numerical results show that the proposed auction scheme not only improves the PT’s security but also increases the access opportunities of the STs. Project supported by the National Natural Science Foundation of China (Grant Nos. 61271232 and 61372126) and the University Postgraduate Research and Innovation Project in Jiangsu Province, China (Grant No. CXZZ12-0472).

[Social stigma and the families of patients with tuberculosis: a study based on cluster and multiple correspondence analysis].

PubMed

Touso, Michelle Mosna; Popolin, Marcela Paschoal; Crispim, Juliane de Almeida; Freitas, Isabela Moreira de; Rodrigues, Ludmila Barbosa Bandeira; Yamamura, Mellina; Pinto, Ione Carvalho; Monroe, Aline Aparecida; Palha, Pedro Fredemir; Ferraudo, Antônio Sérgio; Villa, Tereza Cristina Scatena; Arcêncio, Ricardo Alexandre

2014-11-01

The social stigma associated with TB is a challenge facing management of the area of public health care. The aim of this study was to investigate the social stigma in families of patients with TB and identify the profile of those who are affected by the event in relation to socioeconomic and demographic conditions. It is a cross-sectional study that was conducted in 2011 in the city of Ribeirão Preto, state of São Paulo, Brazil, with a sample of 110 individuals. The data were analyzed using the univariate descriptive technique and cluster and multiple correspondence assessment. The stigmatized groups tend to have lower scholarity, incipient access to the media and little understanding about TB, as opposed to those that have higher educational levels, continuous access to the media, consider themselves well informed and show proactive attitudes to deal with the disease. The identification of varied profiles highlights the need to develop health interventions to cater to the singularities of families with respect to the social stigma of the disease.

A Novel Technique to Detect Code for SAC-OCDMA System

NASA Astrophysics Data System (ADS)

Bharti, Manisha; Kumar, Manoj; Sharma, Ajay K.

2018-04-01

The main task of optical code division multiple access (OCDMA) system is the detection of code used by a user in presence of multiple access interference (MAI). In this paper, new method of detection known as XOR subtraction detection for spectral amplitude coding OCDMA (SAC-OCDMA) based on double weight codes has been proposed and presented. As MAI is the main source of performance deterioration in OCDMA system, therefore, SAC technique is used in this paper to eliminate the effect of MAI up to a large extent. A comparative analysis is then made between the proposed scheme and other conventional detection schemes used like complimentary subtraction detection, AND subtraction detection and NAND subtraction detection. The system performance is characterized by Q-factor, BER and received optical power (ROP) with respect to input laser power and fiber length. The theoretical and simulation investigations reveal that the proposed detection technique provides better quality factor, security and received power in comparison to other conventional techniques. The wide opening of eye in case of proposed technique also proves its robustness.

Integrated databanks access and sequence/structure analysis services at the PBIL.

PubMed

Perrière, Guy; Combet, Christophe; Penel, Simon; Blanchet, Christophe; Thioulouse, Jean; Geourjon, Christophe; Grassot, Julien; Charavay, Céline; Gouy, Manolo; Duret, Laurent; Deléage, Gilbert

2003-07-01

The World Wide Web server of the PBIL (Pôle Bioinformatique Lyonnais) provides on-line access to sequence databanks and to many tools of nucleic acid and protein sequence analyses. This server allows to query nucleotide sequence banks in the EMBL and GenBank formats and protein sequence banks in the SWISS-PROT and PIR formats. The query engine on which our data bank access is based is the ACNUC system. It allows the possibility to build complex queries to access functional zones of biological interest and to retrieve large sequence sets. Of special interest are the unique features provided by this system to query the data banks of gene families developed at the PBIL. The server also provides access to a wide range of sequence analysis methods: similarity search programs, multiple alignments, protein structure prediction and multivariate statistics. An originality of this server is the integration of these two aspects: sequence retrieval and sequence analysis. Indeed, thanks to the introduction of re-usable lists, it is possible to perform treatments on large sets of data. The PBIL server can be reached at: http://pbil.univ-lyon1.fr.

Factors influencing eating a varied diet in old age.

PubMed

Dean, Moira; Raats, Monique M; Grunert, Klaus G; Lumbers, Margaret

2009-12-01

To investigate the influences of resources and food-related goals on the variety of food choice among older people. A questionnaire-based survey in eight European countries: Poland, Portugal, United Kingdom, Germany, Sweden, Denmark, Italy and Spain. Participants (n 3200) were above 65 years of age and living in their own homes. The samples were quota samples, eight groups of fifty in each country, based on gender, age and living circumstances, reflecting the diversity of each of the national populations based on education, income and urbanization of living environment. Hierarchical multiple regression analysis showed that income, health status, access to a car and living arrangement affected the level of dietary variety. The perceived level of different food-related resources impacted the consumption of a varied diet over and above actual resource levels. Food-related goals contributed to variety of food intake that was not accounted for by the amount of material resources possessed or the social and other resources perceived to be possessed. Older people's variety of food intake depended on material resources (e.g. monthly income, access to a car, living arrangement, physical and mental health). However, in addition to these variables, the way older people perceived other resources, such as their level of appetite, their food knowledge, their perception of the distance to the shops, access to high-quality products, having better kitchen facilities, access to good service providers and support from friends and neighbours, all contributed to how varied a diet they ate.

Increased access to palliative care and hospice services: opportunities to improve value in health care.

PubMed

Meier, Diane E

2011-09-01

A small proportion of patients with serious illness or multiple chronic conditions account for the majority of health care spending. Despite the high cost, evidence demonstrates that these patients receive health care of inadequate quality, characterized by fragmentation, overuse, medical errors, and poor quality of life. This article examines data demonstrating the impact of the U.S. health care system on clinical care outcomes and costs for the sickest and most vulnerable patients. It also defines palliative care and hospice, synthesizes studies of the outcomes of palliative care and hospice services, reviews variables predicting access to palliative care and hospice services, and identifies those policy priorities necessary to strengthen access to high-quality palliative care. Palliative care and hospice services improve patient-centered outcomes such as pain, depression, and other symptoms; patient and family satisfaction; and the receipt of care in the place that the patient chooses. Some data suggest that, compared with the usual care, palliative care prolongs life. By helping patients get the care they need to avoid unnecessary emergency department and hospital stays and shifting the locus of care to the home or community, palliative care and hospice reduce health care spending for America's sickest and most costly patient populations. Policies focused on enhancing the palliative care workforce, investing in the field's science base, and increasing the availability of services in U.S. hospitals and nursing homes are needed to ensure equitable access to optimal care for seriously ill patients and those with multiple chronic conditions. © 2011 Milbank Memorial Fund. Published by Wiley Periodicals Inc.

Increased Access to Palliative Care and Hospice Services: Opportunities to Improve Value in Health Care

PubMed Central

Meier, Diane E

2011-01-01

Context: A small proportion of patients with serious illness or multiple chronic conditions account for the majority of health care spending. Despite the high cost, evidence demonstrates that these patients receive health care of inadequate quality, characterized by fragmentation, overuse, medical errors, and poor quality of life. Methods: This article examines data demonstrating the impact of the U.S. health care system on clinical care outcomes and costs for the sickest and most vulnerable patients. It also defines palliative care and hospice, synthesizes studies of the outcomes of palliative care and hospice services, reviews variables predicting access to palliative care and hospice services, and identifies those policy priorities necessary to strengthen access to high-quality palliative care. Findings: Palliative care and hospice services improve patient-centered outcomes such as pain, depression, and other symptoms; patient and family satisfaction; and the receipt of care in the place that the patient chooses. Some data suggest that, compared with the usual care, palliative care prolongs life. By helping patients get the care they need to avoid unnecessary emergency department and hospital stays and shifting the locus of care to the home or community, palliative care and hospice reduce health care spending for America's sickest and most costly patient populations. Conclusions: Policies focused on enhancing the palliative care workforce, investing in the field's science base, and increasing the availability of services in U.S. hospitals and nursing homes are needed to ensure equitable access to optimal care for seriously ill patients and those with multiple chronic conditions. PMID:21933272

National Scale Marine Geophysical Data Portal for the Israel EEZ with Public Access Web-GIS Platform

NASA Astrophysics Data System (ADS)

Ketter, T.; Kanari, M.; Tibor, G.

2017-12-01

Recent offshore discoveries and regulation in the Israel Exclusive Economic Zone (EEZ) are the driving forces behind increasing marine research and development initiatives such as infrastructure development, environmental protection and decision making among many others. All marine operations rely on existing seabed information, while some also generate new data. We aim to create a single platform knowledge-base to enable access to existing information, in a comprehensive, publicly accessible web-based interface. The Israel EEZ covers approx. 26,000 sqkm and has been surveyed continuously with various geophysical instruments over the past decades, including 10,000 km of multibeam survey lines, 8,000 km of sub-bottom seismic lines, and hundreds of sediment sampling stations. Our database consists of vector and raster datasets from multiple sources compiled into a repository of geophysical data and metadata, acquired nation-wide by several research institutes and universities. The repository will enable public access via a web portal based on a GIS platform, including datasets from multibeam, sub-bottom profiling, single- and multi-channel seismic surveys and sediment sampling analysis. Respective data products will also be available e.g. bathymetry, substrate type, granulometry, geological structure etc. Operating a web-GIS based repository allows retrieval of pre-existing data for potential users to facilitate planning of future activities e.g. conducting marine surveys, construction of marine infrastructure and other private or public projects. User interface is based on map oriented spatial selection, which will reveal any relevant data for designated areas of interest. Querying the database will allow the user to obtain information about the data owner and to address them for data retrieval as required. Wide and free public access to existing data and metadata can save time and funds for academia, government and commercial sectors, while aiding in cooperation and data sharing among the various stakeholders.

A Knowledge-Modeling Approach to Integrate Multiple Clinical Practice Guidelines to Provide Evidence-Based Clinical Decision Support for Managing Comorbid Conditions.

PubMed

Abidi, Samina

2017-10-26

Clinical management of comorbidities is a challenge, especially in a clinical decision support setting, as it requires the safe and efficient reconciliation of multiple disease-specific clinical procedures to formulate a comorbid therapeutic plan that is both effective and safe for the patient. In this paper we pursue the integration of multiple disease-specific Clinical Practice Guidelines (CPG) in order to manage co-morbidities within a computerized Clinical Decision Support System (CDSS). We present a CPG integration framework-termed as COMET (Comorbidity Ontological Modeling & ExecuTion) that manifests a knowledge management approach to model, computerize and integrate multiple CPG to yield a comorbid CPG knowledge model that upon execution can provide evidence-based recommendations for handling comorbid patients. COMET exploits semantic web technologies to achieve (a) CPG knowledge synthesis to translate a paper-based CPG to disease-specific clinical pathways (CP) that include specialized co-morbidity management procedures based on input from domain experts; (b) CPG knowledge modeling to computerize the disease-specific CP using a Comorbidity CPG ontology; (c) CPG knowledge integration by aligning multiple ontologically-modeled CP to develop a unified comorbid CPG knowledge model; and (e) CPG knowledge execution using reasoning engines to derive CPG-mediated recommendations for managing patients with comorbidities. We present a web-accessible COMET CDSS that provides family physicians with CPG-mediated comorbidity decision support to manage Atrial Fibrillation and Chronic Heart Failure. We present our qualitative and quantitative analysis of the knowledge content and usability of COMET CDSS.

Power adaptive multi-filter carrierless amplitude and phase access scheme for visible light communication network

NASA Astrophysics Data System (ADS)

Li, Wei; Huang, Zhitong; Li, Haoyue; Ji, Yuefeng

2018-04-01

Visible light communication (VLC) is a promising candidate for short-range broadband access due to its integration of advantages for both optical communication and wireless communication, whereas multi-user access is a key problem because of the intra-cell and inter-cell interferences. In addition, the non-flat channel effect results in higher losses for users in high frequency bands, which leads to unfair qualities. To solve those issues, we propose a power adaptive multi-filter carrierless amplitude and phase access (PA-MF-CAPA) scheme, and in the first step of this scheme, the MF-CAPA scheme utilizing multiple filters as different CAP dimensions is used to realize multi-user access. The character of orthogonality among the filters in different dimensions can mitigate the effect of intra-cell and inter-cell interferences. Moreover, the MF-CAPA scheme provides different channels modulated on the same frequency bands, which further increases the transmission rate. Then, the power adaptive procedure based on MF-CAPA scheme is presented to realize quality fairness. As demonstrated in our experiments, the MF-CAPA scheme yields an improved throughput compared with multi-band CAP access scheme, and the PA-MF-CAPA scheme enhances the quality fairness and further improves the throughput compared with the MF-CAPA scheme.

Assessing communication accessibility in the university classroom: towards a goal of universal hearing accessibility.

PubMed

Cheesman, Margaret F; Jennings, Mary Beth; Klinger, Lisa

2013-01-01

Measures of accessibility typically focus on the physical environment and aspects relating to getting into and out of spaces. The transient sound environment is less well characterized in typical accessibility measures. Hearing accessibility measures can be based upon physical indices or functional assessment. The physical measures are indices that use signal-to-noise ratios to evaluate audibility while the functional assessment tool adopts universal design for hearing (UDH) principles derived from principles of universal design. The UDH principles include (1) Optimization of the hearing environment for all; (2) Optimization of interactions between persons and objects to promote better hearing in an environment; (3) Optimization of opportunities for people to have multiple choices of interactions with one another; (4) Optimization of opportunities for people to perform different activities in and across environments; (5) Optimization of opportunities for people to have safe, private, and secure use of the environment while minimizing distraction, interference, or cognitive loading; and (6) Optimization of opportunities for people to use the environment without extra steps for hearing access during preparatory, use and/or after use phases. This paper compares the two approaches using case examples from post-secondary classrooms in order to describe the potential advantages and limitations of each.

An Efficient Downlink Scheduling Strategy Using Normal Graphs for Multiuser MIMO Wireless Systems

NASA Astrophysics Data System (ADS)

Chen, Jung-Chieh; Wu, Cheng-Hsuan; Lee, Yao-Nan; Wen, Chao-Kai

Inspired by the success of the low-density parity-check (LDPC) codes in the field of error-control coding, in this paper we propose transforming the downlink multiuser multiple-input multiple-output scheduling problem into an LDPC-like problem using the normal graph. Based on the normal graph framework, soft information, which indicates the probability that each user will be scheduled to transmit packets at the access point through a specified angle-frequency sub-channel, is exchanged among the local processors to iteratively optimize the multiuser transmission schedule. Computer simulations show that the proposed algorithm can efficiently schedule simultaneous multiuser transmission which then increases the overall channel utilization and reduces the average packet delay.

Calculating with light using a chip-scale all-optical abacus.

PubMed

Feldmann, J; Stegmaier, M; Gruhler, N; Ríos, C; Bhaskaran, H; Wright, C D; Pernice, W H P

2017-11-02

Machines that simultaneously process and store multistate data at one and the same location can provide a new class of fast, powerful and efficient general-purpose computers. We demonstrate the central element of an all-optical calculator, a photonic abacus, which provides multistate compute-and-store operation by integrating functional phase-change materials with nanophotonic chips. With picosecond optical pulses we perform the fundamental arithmetic operations of addition, subtraction, multiplication, and division, including a carryover into multiple cells. This basic processing unit is embedded into a scalable phase-change photonic network and addressed optically through a two-pulse random access scheme. Our framework provides first steps towards light-based non-von Neumann arithmetic.

The LASP Interactive Solar IRradiance Datacenter (LISIRD)

NASA Astrophysics Data System (ADS)

Pankratz, C. K.; Lindholm, D. M.; Snow, M.; Knapp, B.; Woodraska, D.; Templeman, B.; Woods, T. N.; Eparvier, F. G.; Fontenla, J.; Harder, J.; McClintock, W. E.

2007-12-01

The Laboratory for Atmospheric and Space Physics (LASP) has been making space-based measurements of solar irradiance for many decades, and thus has established an extensive catalog of past and ongoing space- based solar irradiance measurements. In order to maximize the accessibility and usability of solar irradiance data and information from multiple missions, LASP is developing the LASP Interactive Solar IRradiance Datacenter (LISIRD) to better serve the needs of researchers, educators, and the general public. This data center is providing interactive and direct access to a comprehensive set of solar spectral irradiance measurements from the soft X-ray (XUV) at 0.1 nm up to the near infrared (NIR) at 2400 nm, as well as state-of-the-art measurements of Total Solar Irradiance (TSI). LASP researchers are also responsible for an extensive set of solar irradiance models and historical solar irradiance reconstructions, which will also be accessible via this data center over time. LISIRD currently provides access to solar irradiance data sets from the SORCE, TIMED-SEE, UARS-SOLSTICE, and SME instruments, spanning 1981 to the present, as well as a Lyman Alpha composite that is available from 1947 to the present. LISIRD also provides data products of interest to the space weather community, whose needs demand high time cadence and near real-time data delivery. This poster provides an overview of the LISIRD system, summarizes the data sets currently available, describes future plans and capabilities, and provides details on how to access solar irradiance data through LISIRD's various interfaces.

Protocol, Engineering Research Center, University of California, Santa Barbara

DTIC Science & Technology

2005-12-01

minimizing the energy consumption in idle periods. We have designed an asynchronous wakeup schedule based on the theory of block designs. The idea is...performance of ad hoc networks through innovative packet scheduling (Baker). "* Developed a number of novel schemes to ensure loop freedom in on demand routing...network nodes to schedule their transmissions to avoid collisions (Garcia-Luna-Aceves). "* Designed and analyzed the Hybrid Activation Multiple Access (HAMA

Feedback Power Control Strategies in Wireless Sensor Networks with Joint Channel Decoding

PubMed Central

Abrardo, Andrea; Ferrari, Gianluigi; Martalò, Marco; Perna, Fabio

2009-01-01

In this paper, we derive feedback power control strategies for block-faded multiple access schemes with correlated sources and joint channel decoding (JCD). In particular, upon the derivation of the feasible signal-to-noise ratio (SNR) region for the considered multiple access schemes, i.e., the multidimensional SNR region where error-free communications are, in principle, possible, two feedback power control strategies are proposed: (i) a classical feedback power control strategy, which aims at equalizing all link SNRs at the access point (AP), and (ii) an innovative optimized feedback power control strategy, which tries to make the network operational point fall in the feasible SNR region at the lowest overall transmit energy consumption. These strategies will be referred to as “balanced SNR” and “unbalanced SNR,” respectively. While they require, in principle, an unlimited power control range at the sources, we also propose practical versions with a limited power control range. We preliminary consider a scenario with orthogonal links and ideal feedback. Then, we analyze the robustness of the proposed power control strategies to possible non-idealities, in terms of residual multiple access interference and noisy feedback channels. Finally, we successfully apply the proposed feedback power control strategies to a limiting case of the class of considered multiple access schemes, namely a central estimating officer (CEO) scenario, where the sensors observe noisy versions of a common binary information sequence and the AP's goal is to estimate this sequence by properly fusing the soft-output information output by the JCD algorithm. PMID:22291536

Influence of Internet Accessibility and Demographic factors on utilization of Web-based Health Information Resources by Resident Doctors in Nigeria

PubMed Central

Ajuwon, GA; Popoola, SO

2015-01-01

Background The internet is a huge library with avalanche of information resources including healthcare information. There are numerous studies on use of electronic resources by healthcare providers including medical practitioners however, there is a dearth of information on the patterns of use of web-based health information resource by resident doctors in Nigeria. This study therefore investigates the influence of internet accessibility and demographic factors on utilization of web-based health information resources by resident doctors in tertiary healthcare institutions in Nigeria. Methods Descriptive survey design was adopted for this study. The population of study consisted of medical doctors undergoing residency training in 13 tertiary healthcare institutions in South-West Nigeria. The tertiary healthcare institutions were Federal Medical Centres, University Teaching Hospitals and Specialist Hospitals (Neuropsychiatric and Orthopaedic). A pre-tested, self-administered questionnaire was used for data collection. The Statistical Package for the Social Sciences (SPSS) was used for data analysis. Data were analyzed using descriptive statistics, Pearson Product Moment correlation and multiple regression analysis. Results The mean age of the respondents was 34 years and males were in the majority (69.0%). A total of 96.1% respondents had access to the Internet. E-mail (X̄=5.40, SD=0.91), Google (X̄=5.26, SD=1.38), Yahoo (X̄=5.15, SD=4.44) were used weekly by the respondents. Preparation for Seminar/Grand Round presentation (X̄=8.4, SD=1.92), research (X̄=7.8, SD=2.70) and communication (X̄=7.6, SD=2.60) were ranked high as purposes for use of web-based information resources. There is a strong, positive and significant relationship between internet accessibility and utilization of web-based health information resources (r=0.628, p<0.05). Internet accessibility (B=0.911) and demographic factors: gender (B=−2.027), designation (B=−0.343) educational qualification (B=2.411) significantly influence utilization of web-based health information resources of the respondents. Conclusion A great majority of the respondents have access to the Internet and used web-based health information resources more for academic purposes than patient care. Training is required to promote use of internet health information resources among resident doctors. The findings of this study will be useful to the management of the 13 healthcare institutions regarding provision of appropriate internet facilities that will enhance access and use of web-based health information resources by resident doctors. PMID:26681825

Influence of Internet Accessibility and Demographic factors on utilization of Web-based Health Information Resources by Resident Doctors in Nigeria.

PubMed

Ajuwon, G A; Popoola, S O

2014-09-01

The internet is a huge library with avalanche of information resources including healthcare information. There are numerous studies on use of electronic resources by healthcare providers including medical practitioners however, there is a dearth of information on the patterns of use of web-based health information resource by resident doctors in Nigeria. This study therefore investigates the influence of internet accessibility and demographic factors on utilization of web-based health information resources by resident doctors in tertiary healthcare institutions in Nigeria. Descriptive survey design was adopted for this study. The population of study consisted of medical doctors undergoing residency training in 13 tertiary healthcare institutions in South-West Nigeria. The tertiary healthcare institutions were Federal Medical Centres, University Teaching Hospitals and Specialist Hospitals (Neuropsychiatric and Orthopaedic). A pre-tested, self-administered questionnaire was used for data collection. The Statistical Package for the Social Sciences (SPSS) was used for data analysis. Data were analyzed using descriptive statistics, Pearson Product Moment correlation and multiple regression analysis. The mean age of the respondents was 34 years and males were in the majority (69.0%). A total of 96.1% respondents had access to the Internet. E-mail (X̄=5.40, SD=0.91), Google (X̄=5.26, SD=1.38), Yahoo (X̄=5.15, SD=4.44) were used weekly by the respondents. Preparation for Seminar/Grand Round presentation (X̄=8.4, SD=1.92), research (X̄=7.8, SD=2.70) and communication (X̄=7.6, SD=2.60) were ranked high as purposes for use of web-based information resources. There is a strong, positive and significant relationship between internet accessibility and utilization of web-based health information resources (r=0.628, p<0.05). Internet accessibility (B=0.911) and demographic factors: gender (B=-2.027), designation (B=-0.343) educational qualification (B=2.411) significantly influence utilization of web-based health information resources of the respondents. A great majority of the respondents have access to the Internet and used web-based health information resources more for academic purposes than patient care. Training is required to promote use of internet health information resources among resident doctors. The findings of this study will be useful to the management of the 13 healthcare institutions regarding provision of appropriate internet facilities that will enhance access and use of web-based health information resources by resident doctors.

Comparative transcriptome analysis provides new insights into erect and prostrate growth in bermudagrass (Cynodon dactylon L.).

PubMed

Zhang, Bing; Xiao, Xiaolin; Zong, Junqin; Chen, Jingbo; Li, Jianjian; Guo, Hailin; Liu, Jianxiu

2017-12-01

Bermudagrass (Cynodon dactylon L.) is a prominent warm-season turf and forage grass species with multiple applications. In most C. dactylon cultivars and accessions, erect-growing stems (shoot) and prostrate-growing stems (stolon) often coexist. These two types of stems are both formed through tillering but grow in two directions with different tiller angles. Elucidating the mechanism of tiller angle regulation in bermudagrass could provide important clues to breed cultivars with different plant architectural features for diverse usage. In this study, we compared the stem internode transcriptome of two bermudagrass wild accessions with extremely different tiller angles and stem growth directions. A total of 2088 and 12,141 unigenes were preferentially expressed in prostrate-growing wild accession C792 and erect-growing wild accession C793, respectively. Kyoto Encyclopedia of Genes and Genomes (KEGG) Orthology-based Annotation System (KOBAS) analyses further indicated that light- and gravity-responsive genes were enriched in accession C792, whereas lignin synthesis-related genes were enriched in accession C793, which well explains the difference in lignification of vascular bundles and mechanical tissues in the two accessions. These results not only expand our understanding of the genetic control of tiller angle and stem growth direction in bermudagrass but also provide insight for future molecular breeding of C. dactylon and other turfgrass species with different plant architectures. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Fourth Annual International Acquisitions Workshop: Access to Multiple Media Worldwide

NASA Technical Reports Server (NTRS)

1994-01-01

Topics discussed during the workshop include: (1) Multinational-Multiple media collections and activities spanning many countries; (2) Multiple media in North American trade and commerce; (3) African spotlight; (4) Europe-Multiple media in national libraries and services; (5) Scandinavian spotlight; (6) Internet update; (7) Multiple media in US federal agencies; (8) Open-source multiple media in US federal agencies; and (9) Multiple media at US federal technical agencies-NIST and NOAA.

Enhancing the primary care team to provide redesigned care: the roles of practice facilitators and care managers.

PubMed

Taylor, Erin Fries; Machta, Rachel M; Meyers, David S; Genevro, Janice; Peikes, Deborah N

2013-01-01

Efforts to redesign primary care require multiple supports. Two potential members of the primary care team-practice facilitator and care manager-can play important but distinct roles in redesigning and improving care delivery. Facilitators, also known as quality improvement coaches, assist practices with coordinating their quality improvement activities and help build capacity for those activities-reflecting a systems-level approach to improving quality, safety, and implementation of evidence-based practices. Care managers provide direct patient care by coordinating care and helping patients navigate the system, improving access for patients, and communicating across the care team. These complementary roles aim to help primary care practices deliver coordinated, accessible, comprehensive, and patient-centered care.

Video Modeling and Observational Learning to Teach Gaming Access to Students with ASD.

PubMed

Spriggs, Amy D; Gast, David L; Knight, Victoria F

2016-09-01

The purpose of this study was to evaluate both video modeling and observational learning to teach age-appropriate recreation and leisure skills (i.e., accessing video games) to students with autism spectrum disorder. Effects of video modeling were evaluated via a multiple probe design across participants and criteria for mastery were based on these results. Secondary measures were collected on observational learning across participants and behaviors. Participants included 4 children with autism, ages 8-11, who were served in self-contained special education classrooms. Results indicated a functional relation between video modeling and increased independence in gaming; observational learning occurred for at least some steps across students. Results, implications for practitioners, limitations, and ideas for future research are discussed.

ESASky: a new Astronomy Multi-Mission Interface

NASA Astrophysics Data System (ADS)

Baines, D.; Merin, B.; Salgado, J.; Giordano, F.; Sarmiento, M.; Lopez Marti, B.; Racero, E.; Gutierrez, R.; De Teodoro, P.; Nieto, S.

2016-06-01

ESA is working on a science-driven discovery portal for all its astronomy missions at ESAC called ESASky. The first public release of this service will be shown, featuring interfaces for sky exploration and for single and multiple targets. It requires no operational knowledge of any of the missions involved. A first public beta release took place in October 2015 and gives users world-wide simplified access to high-level science-ready data products from ESA Astronomy missions plus a number of ESA-produced source catalogues. XMM-Newton data, metadata and products were some of the first to be accessible through ESASky. In the next decade, ESASky aims to include not only ESA missions but also access to data from other space and ground-based astronomy missions and observatories. From a technical point of view, ESASky is a web application that offers all-sky projections of full mission datasets using a new-generation HEALPix projection called HiPS; detailed geometrical footprints to connect all-sky mosaics to individual observations; direct access to the underlying mission-specific science archives and catalogues. The poster will be accompanied by a demo booth at the conference.

Political, cultural and economic foundations of primary care in Europe.

PubMed

Kringos, Dionne S; Boerma, Wienke G W; van der Zee, Jouke; Groenewegen, Peter P

2013-12-01

This article explores various contributing factors to explain differences in the strength of the primary care (PC) structure and services delivery across Europe. Data on the strength of primary care in 31 European countries in 2009/10 were used. The results showed that the national political agenda, economy, prevailing values, and type of healthcare system are all important factors that influence the development of strong PC. Wealthier countries are associated with a weaker PC structure and lower PC accessibility, while Eastern European countries seemed to have used their growth in national income to strengthen the accessibility and continuity of PC. Countries governed by left-wing governments are associated with a stronger PC structure, accessibility and coordination of PC. Countries with a social-security based system are associated with a lower accessibility and continuity of PC; the opposite is true for transitional systems. Cultural values seemed to affect all aspects of PC. It can be concluded that strengthening PC means mobilising multiple leverage points, policy options, and political will in line with prevailing values in a country. Copyright © 2013 Elsevier Ltd. All rights reserved.

Factors influencing health care access perceptions and care-seeking behaviors of immigrant Latino sexual minority men and transgender individuals: baseline findings from the HOLA intervention study.

PubMed

Tanner, Amanda E; Reboussin, Beth A; Mann, Lilli; Ma, Alice; Song, Eunyoung; Alonzo, Jorge; Rhodes, Scott D

2014-11-01

Little is known about immigrant Latino sexual minorities’ health seeking behaviors. This study examined factors associated with perceptions of access and actual care behaviors among this population in North Carolina. A community-based participatory research partnership recruited 180 Latino sexual minority men and transgender individuals within preexisting social networks to participate in a sexual health intervention. Mixed-effects logistic regression models and GIS mapping examined factors influencing health care access perceptions and use of services (HIV testing and routine check-ups). Results indicate that perceptions of access and actual care behaviors are low and affected by individual and structural factors, including: years living in NC, reported poor general health, perceptions of discrimination, micro-, meso-, and macro-level barriers, and residence in a Medically Underserved Area. To improve Latino sexual minority health, focus must be placed on multiple levels, including: individual characteristics (e.g., demographics), clinic factors (e.g., provider competence and clinic environment), and structural factors (e.g., discrimination).

Factors influencing health care access perceptions and care-seeking behaviors of immigrant Latino sexual minority men and transgender individuals: Baseline findings from the HOLA intervention study

PubMed Central

Tanner, AE; Reboussin, BA; Mann, L; Ma, A; Song, E; Alonzo, J; Rhodes, SD

2014-01-01

Little is known about immigrant Latino sexual minorities' health seeking behaviors. This study examined factors associated with perceptions of access and actual care behaviors among this population in North Carolina. Methods A community-based participatory research partnership recruited 180 Latino sexual minority men and transgender individuals within preexisting social networks to participate in a sexual health intervention. Mixed-effects logistic regression models examined factors influencing health care access perceptions and use of services (HIV testing and routine check-ups). Results Results indicate that perceptions of access and actual care behaviors are low and affected by individual and structural factors, including: years living in NC, reported poor general health, perceptions of discrimination, micro-, meso-, and macro-level barriers, and residence in a Medically Underserved Area. Discussion To improve Latino sexual minority health, focus must be placed on multiple levels, individual characteristics (e.g., demographics), clinic factors (e.g., provider competence and clinic environment), and structural factors (e.g., discrimination). PMID:25418235

Name-Based Address Mapping for Virtual Private Networks

NASA Astrophysics Data System (ADS)

Surányi, Péter; Shinjo, Yasushi; Kato, Kazuhiko

IPv4 private addresses are commonly used in local area networks (LANs). With the increasing popularity of virtual private networks (VPNs), it has become common that a user connects to multiple LANs at the same time. However, private address ranges for LANs frequently overlap. In such cases, existing systems do not allow the user to access the resources on all LANs at the same time. In this paper, we propose name-based address mapping for VPNs, a novel method that allows connecting to hosts through multiple VPNs at the same time, even when the address ranges of the VPNs overlap. In name-based address mapping, rather than using the IP addresses used on the LANs (the real addresses), we assign a unique virtual address to each remote host based on its domain name. The local host uses the virtual addresses to communicate with remote hosts. We have implemented name-based address mapping for layer 3 OpenVPN connections on Linux and measured its performance. The communication overhead of our system is less than 1.5% for throughput and less than 0.2ms for each name resolution.

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.

Analog and digital transport of RF channels over converged 5G wireless-optical networks

NASA Astrophysics Data System (ADS)

Binh, Le Nguyen

2016-02-01

Under the exponential increase demand by the emerging 5G wireless access networking and thus data-center based Internet, novel and economical transport of RF channels to and from wireless access systems. This paper presents the transport technologies of RF channels over the analog and digital domain so as to meet the demands of the transport capacity reaching multi-Tbps, in the followings: (i) The convergence of 5G broadband wireless and optical networks and its demands on capacity delivery and network structures; (ii) Analog optical technologies for delivery of both the information and RF carriers to and from multiple-input multiple-output (MIMO) antenna sites so as to control the beam steering of MIMO antenna in the mmW at either 28.6 GHz and 56.8 GHz RF carrier and delivery of channels of aggregate capacity reaching several Tbps; (ii) Transceiver employing advanced digital modulation formats and digital signal processing (DSP) so as to provide 100G and beyond transmission rate to meet the ultra-high capacity demands with flexible spectral grids, hence pay-on-demand services. The interplay between DSP-based and analog transport techniques is examined; (iii) Transport technologies for 5G cloud access networks and associate modulation and digital processing techniques for capacity efficiency; and (iv) Finally the integrated optic technologies with novel lasers, comb generators and simultaneous dual function photonic devices for both demultiplexing/multiplexing and modulation are proposed, hence a system on chip structure can be structured. Quantum dot lasers and matrixes of micro ring resonators are integrated on the same Si-on-Silica substrate are proposed and described.

Telehealth on advanced networks.

PubMed

Wilson, Laurence S; Stevenson, Duncan R; Cregan, Patrick

2010-01-01

We address advanced Internet for complex telehealth applications by reviewing four hospital-based broadband telehealth projects and identifying common threads. These projects were conducted in Australia under a 6-year research project on broadband Internet applications. Each project addressed specific clinical needs and its development was guided by the clinicians involved. Each project was trialed in the field and evaluated against the initial requirements. The four projects covered remote management of a resuscitation team in a district hospital, remote guidance and interpretation of echocardiography, virtual-reality-based instructor-student surgical training, and postoperative outpatient consultations following pediatric surgery. Each was characterized by a high level of interpersonal communication, a high level of clinical expertise, and multiple participants. Each made use of multiple high-quality video and audio links and shared real-time access to clinical data. Four common threads were observed. Each application provided a high level of usability and task focus because the design and use of broadband capability was aimed directly to meet the clinicians' needs. Each used the media quality available over broadband to convey words, gestures, body movements, and facial expressions to support communication and a sense of presence among the participants. Each required a complex information space shared among the participants, including real-time access to stored patient data and real-time interactive access to the patients themselves. Finally, each application supported the social and organizational aspects of their healthcare focus, creating and maintaining relationships between the various participants, and this was done by placing the telehealth application into a wider functioning clinical context. These findings provide evidence for a significantly enhanced role for appropriate telemedicine systems running on advanced networks, in a wider range of clinical applications, more deeply integrated into healthcare systems.

Accessing and visualizing scientific spatiotemporal data

NASA Technical Reports Server (NTRS)

Katz, Daniel S.; Bergou, Attila; Berriman, G. Bruce; Block, Gary L.; Collier, Jim; Curkendall, David W.; Good, John; Husman, Laura; Jacob, Joseph C.; Laity, Anastasia;

Hand washing behavior and associated factors in Vietnam based on the Multiple Indicator Cluster Survey, 2010–2011

PubMed Central

To, Kien Gia; Lee, Jong-Koo; Nam, You-Seon; Trinh, Oanh Thi Hoang; Van Do, Dung

2016-01-01

Background Handwashing is a cost-effective way of preventing communicable diseases such as respiratory and food-borne illnesses. However, handwashing rates are low in developing countries. Target 7C of the seventh Millennium Development Goals was to increase by half the proportion of people with sustainable access to safe drinking water and basic sanitation by 2015. Studies have found that better access to improved water sources and sanitation is associated with higher rates of handwashing. Objective Our goal was to describe handwashing behaviour and identify the associated factors in Vietnamese households. Design Data from 12,000 households participating in the Vietnam Multiple Indicator Cluster Survey 2011 were used. The survey used a multistage sampling method to randomly select 100 clusters and 20 households per cluster. Self-administered questionnaires were used to collect data from a household representative. Demographic variables, the presence of a specific place for handwashing, soap and water, access to improved sanitation, and access to improved water sources were tested for association with handwashing behaviour in logistic regression. Results Almost 98% of households had a specific place for handwashing, and 85% had cleansing materials and water at such a place. The prevalence of handwashing in the sample was almost 85%. Educational level, ethnicity of the household head, and household wealth were factors associated with handwashing practice (p<0.05). Those having access to an improved sanitation facility were more likely to practise handwashing [odds ratio (OR)=1.69, 95% confidence interval (CI): 1.37–2.09, p<0.001], as were those with access to improved water sources (OR=1.74, 95% CI: 1.37–2.21, p<0.001). Conclusions Households with low education, low wealth, belonging to ethnic minorities, and with low access to improved sanitation facilities and water sources should be targeted for interventions implementing handwashing practice. In addition, the availability of soap and water at handwashing sites should be increased and practical teaching programs should be deployed in order to increase handwashing rates. PMID:26950556

Broadband Time Division Multiple Access (TDMA) Solution (Tech Insertion - C4 Enhancement for the U.S. Army in Transformation)

DTIC Science & Technology

2005-06-01

synchronization , timing and frequency to all of the traffic terminals through the reference burst. The MRT also periodically synchronizes all of the traffic...1 2005 Command and Control Research and Technology Symposium The Future of C2 Broadband Time Division Multiple Access (TDMA) Solution...UK Army) Dale White Barry Kruse Shawn White LTC Edward Eidson Thomas Mims COL Charles Dunn III Charlie Pangle Battle Command Battle

Virtual Computing Laboratories: A Case Study with Comparisons to Physical Computing Laboratories

ERIC Educational Resources Information Center

Burd, Stephen D.; Seazzu, Alessandro F.; Conway, Christopher

2009-01-01

Current technology enables schools to provide remote or virtual computing labs that can be implemented in multiple ways ranging from remote access to banks of dedicated workstations to sophisticated access to large-scale servers hosting virtualized workstations. This paper reports on the implementation of a specific lab using remote access to…

The introduction and evaluation of mobile devices to improve access to patient records: a catalyst for innovation and collaboration at BCCA.

PubMed

Wu, Jonn; Waldron, John; Hood, Shaina; Kahnamelli, Adam; Khan, Mohamed; Barnett, Jeff; French, John; Slager, Stacey; Melhem, Shadi; Shabestari, Omid

2013-01-01

Prompt and efficient access to patient records is vital in providing optimal patient care. The Cancer Agency Information System (CAIS) is the primary patient record repository for the British Columbia Cancer Agency (BCCA) but is only accessible on traditional computer workstations. The BCCA clinics have significant space limitations resulting in multiple health care professionals sharing each workstation. Furthermore, workstations are not available in examination rooms. A novel and cost efficient solution is necessary to improve clinician access to CAIS. This prompted the BCCA and IMITS to embark on an innovative provincial collaboration to introduce and evaluate the impact of a mobile device to improve access to CAIS. The project consisted of 2 phases with over 50 participants from multiple clinical disciplines across BCCA sites. Phase I evaluated the adoptability, effectiveness and costs associated with providing access to CAIS using a generic viewer (Citrix). Phase II incorporated the feedback and findings from Phase I to make available a customized mobile device-specific application. Phase II also addressed privacy and security requirements.

Multiple Object Based RFID System Using Security Level

NASA Astrophysics Data System (ADS)

Kim, Jiyeon; Jung, Jongjin; Ryu, Ukjae; Ko, Hoon; Joe, Susan; Lee, Yongjun; Kim, Boyeon; Chang, Yunseok; Lee, Kyoonha

2007-12-01

RFID systems are increasingly applied for operational convenience in wide range of industries and individual life. However, it is uneasy for a person to control many tags because common RFID systems have the restriction that a tag used to identify just a single object. In addition, RFID systems can make some serious problems in violation of privacy and security because of their radio frequency communication. In this paper, we propose a multiple object RFID tag which can keep multiple object identifiers for different applications in a same tag. The proposed tag allows simultaneous access for their pair applications. We also propose an authentication protocol for multiple object tag to prevent serious problems of security and privacy in RFID applications. Especially, we focus on efficiency of the authentication protocol by considering security levels of applications. In the proposed protocol, the applications go through different authentication procedures according to security level of the object identifier stored in the tag. We implemented the proposed RFID scheme and made experimental results about efficiency and stability for the scheme.

Piloting an email-based resource package for job seekers with multiple sclerosis.

PubMed

Dorstyn, Diana; Roberts, Rachel; Murphy, Gregory; Kneebone, Ian; Migliorini, Christine; Craig, Ashley; Hutchinson, Claire; Field, Deborah

2017-05-01

Media-based rehabilitation provides a powerful opportunity to examine vocational behaviors in the disability sector. However, this research is preliminary at best. This paper reports pilot data. Eighteen adults with multiple sclerosis (MS) accessed an email-delivered, resource-based package, Work and MS. Pre- and post-access vocational self-efficacy and identity (Job-Procurement Self Efficacy Scale, My Vocational Situation Scale- primary outcomes), life orientation and depressed mood (Life Orientation Test - revised and Patient Health Questionnaire-9 - secondary outcomes) were assessed. Pre- and post-change scores were examined with Wilcoxon signed ranks tests and Hedges g effect sizes with associated 95% confidence intervals. Reliable change analyses were additionally calculated to determine the clinical significance of individual change scores. Significant and positive effects were reported for vocational self-efficacy, identity, and optimism. Reliable change scores in one or more of these key outcomes were reported by 30% of the sample. Satisfaction with the content and delivery of the email-based intervention was also noted. Preliminary evidence suggests that Work and MS can help to promote vocational goals, interests and strengths among job seekers with a disability by providing a set of tools, information and linkages relating to vocational pursuits and career development. Replication with a randomized control design is indicated. Implications for Rehabilitation Research indicates a high unemployment rate among working-age adults with MS. A combination of disease-specific, psychological, programmatic and societal variables contribute to employment instability in this group. This pilot study demonstrates that an e-mail-based resource package, Work and MS, provides an innovative and feasible option for promoting consumer engagement with vocational services and, potentially, improving vocational outcomes. Work and MS has potential applicability to other disability groups.

An Intelligent Terminal for Access to a Medical Database

PubMed Central

Womble, M. E.; Wilson, S. D.; Keiser, H. N.; Tworek, M. L.

1978-01-01

Very powerful data base management systems (DBMS) now exist which allow medical personnel access to patient record data bases. DBMS's make it easy to retrieve either complete or abbreviated records of patients with similar characteristics. In addition, statistics on data base records are immediately accessible. However, the price of this power is a large computer with the inherent problems of access, response time, and reliability. If a general purpose, time-shared computer is used to get this power, the response time to a request can be either rapid or slow, depending upon loading by other users. Furthermore, if the computer is accessed via dial-up telephone lines, there is competition with other users for telephone ports. If either the DBMS or the host machine is replaced, the medical users, who are typically not sophisticated in computer usage, are forced to learn the new system. Microcomputers, because of their low cost and adaptability, lend themselves to a solution of these problems. A microprocessor-based intelligent terminal has been designed and implemented at the USAF School of Aerospace Medicine to provide a transparent interface between the user and his data base. The intelligent terminal system includes multiple microprocessors, floppy disks, a CRT terminal, and a printer. Users interact with the system at the CRT terminal using menu selection (framing). The system translates the menu selection into the query language of the DBMS and handles all actual communication with the DBMS and its host computer, including telephone dialing and sign on procedures, as well as the actual data base query and response. Retrieved information is stored locally for CRT display, hard copy production, and/or permanent retention. Microprocessor-based communication units provide security for sensitive medical data through encryption/decryption algorithms and high reliability error detection transmission schemes. Highly modular software design permits adapation to a different DBMS and/or host computer with only minor localized software changes. Importantly, this portability is completely transparent to system users. Although the terminal system is independent of the host computer and its DBMS, it has been linked to a UNIVAC 1108 computer supporting MRI's SYSTEM 2000 DBMS.

Future of Hydroinformatics: Towards Open, Integrated and Interactive Online Platforms

NASA Astrophysics Data System (ADS)

Demir, I.; Krajewski, W. F.

2012-12-01

Hydroinformatics is a domain of science and technology dealing with the management of information in the field of hydrology (IWA, 2011). There is the need for innovative solutions to the challenges towards open information, integration, and communication in the Internet. This presentation provides an overview of the trends and challenges in the future of hydroinformatics, and demonstrates an information system, Iowa Flood Information System (IFIS), developed within the light of these challenges. The IFIS is a web-based platform developed by the Iowa Flood Center (IFC) to provide access to flood inundation maps, real-time flood conditions, flood forecasts both short-term and seasonal, flood-related data, information and interactive visualizations for communities in Iowa. The key element of the system's architecture is the notion of community. Locations of the communities, those near streams and rivers, define basin boundaries. The IFIS provides community-centric watershed and river characteristics, weather (rainfall) conditions, and streamflow data and visualization tools. Interactive interfaces allow access to inundation maps for different stage and return period values, and flooding scenarios with contributions from multiple rivers. Real-time and historical data of water levels, gauge heights, and rainfall conditions are available in the IFIS by streaming data from automated IFC bridge sensors, USGS stream gauges, NEXRAD radars, and NWS forecasts. 2D and 3D interactive visualizations in the IFIS make the data more understandable to general public. Users are able to filter data sources for their communities and selected rivers. The data and information on IFIS is also accessible through web services and mobile applications. The IFIS is optimized for various browsers and screen sizes to provide access through multiple platforms including tablets and mobile devices. The IFIS includes a rainfall-runoff forecast model to provide a five-day flood risk estimate for more than 1000 communities in Iowa. Multiple view modes in the IFIS accommodate different user types from general public to researchers and decision makers by providing different level of tools and details. River view mode allows users to visualize data from multiple IFC bridge sensors and USGS stream gauges to follow flooding condition along a river. The IFIS will help communities make better-informed decisions on the occurrence of floods, and will alert communities in advance to help minimize damage of floods.

Performance evaluation of modulation and multiple access schemes in ultraviolet optical wireless connections for two atmosphere thickness cases.

PubMed

Raptis, Nikos; Pikasis, Evangelos; Syvridis, Dimitris

2016-08-01

The exploitation of optical wireless communication channels in a non-line-of-sight regime is studied for point-to-point and networking configurations considering the use of light-emitting diodes. Two environments with different scattering center densities are considered, assuming operation at 265 nm. The bit error rate performance of both pulsed and multicarrier modulation schemes is examined, using numerical approaches. In the networking scenario, a central node only receives data, one node transmits useful data, and the rest of them act as interferers. The performance of the desirable node's transmissions is evaluated. The access to the medium is controlled by a code division multiple access scheme.

Apollo: Giving application developers a single point of access to public health models using structured vocabularies and Web services

PubMed Central

Wagner, Michael M.; Levander, John D.; Brown, Shawn; Hogan, William R.; Millett, Nicholas; Hanna, Josh

2013-01-01

This paper describes the Apollo Web Services and Apollo-SV, its related ontology. The Apollo Web Services give an end-user application a single point of access to multiple epidemic simulators. An end user can specify an analytic problem—which we define as a configuration and a query of results—exactly once and submit it to multiple epidemic simulators. The end user represents the analytic problem using a standard syntax and vocabulary, not the native languages of the simulators. We have demonstrated the feasibility of this design by implementing a set of Apollo services that provide access to two epidemic simulators and two visualizer services. PMID:24551417

Apollo: giving application developers a single point of access to public health models using structured vocabularies and Web services.

PubMed

Wagner, Michael M; Levander, John D; Brown, Shawn; Hogan, William R; Millett, Nicholas; Hanna, Josh

2013-01-01

This paper describes the Apollo Web Services and Apollo-SV, its related ontology. The Apollo Web Services give an end-user application a single point of access to multiple epidemic simulators. An end user can specify an analytic problem-which we define as a configuration and a query of results-exactly once and submit it to multiple epidemic simulators. The end user represents the analytic problem using a standard syntax and vocabulary, not the native languages of the simulators. We have demonstrated the feasibility of this design by implementing a set of Apollo services that provide access to two epidemic simulators and two visualizer services.

A simple, effective media access protocol system for integrated, high data rate networks

NASA Technical Reports Server (NTRS)

Foudriat, E. C.; Maly, K.; Overstreet, C. M.; Khanna, S.; Zhang, L.

1992-01-01

The operation and performance of a dual media access protocol for integrated, gigabit networks are described. Unlike other dual protocols, each protocol supports a different class of traffic. The Carrier Sensed Multiple Access-Ring Network (CSMA/RN) protocol and the Circulating Reservation Packet (CRP) protocol support asynchronous and synchronous traffic, respectively. The two protocols operate with minimal impact upon each other. Performance information demonstrates that they support a complete range of integrated traffic loads, do not require call setup/termination or a special node for synchronous traffic control, and provide effective pre-use and recovery. The CRP also provides guaranteed access and fairness control for the asynchronous system. The paper demonstrates that the CSMA-CRP system fulfills many of the requirements for gigabit LAN-MAN networks most effectively and simply. To accomplish this, CSMA-CRP features are compared against similar ring and bus systems, such as Cambridge Fast Ring, Metaring, Cyclic Reservation Multiple Access, and Distributed Dual Queue Data Bus (DQDB).

Impact of patient-centered medical home assignment on emergency room visits among uninsured patients in a county health system.

PubMed

Roby, Dylan H; Pourat, Nadereh; Pirritano, Matthew J; Vrungos, Shelley M; Dajee, Himmet; Castillo, Dan; Kominski, Gerald F

2010-08-01

The Medical Services Initiative program--a safety net-based system of care--in Orange County included assignment of uninsured, low-income residents to a patient-centered medical home. The medical home provided case management, a team-based approach for treating disease, and increased access to primary and specialty care among other elements of a patient-centered medical home. Providers were paid an enhanced fee and pay-for-performance incentives to ensure delivery of comprehensive treatment. Medical Services Initiative enrollees who were assigned to a medical home for longer time periods were less likely to have any emergency room (ER) visits or multiple ER visits. Switching medical homes three or more times was associated with enrollees being more likely to have any ER visits or multiple ER visits. The findings provide evidence that successful implementation of the patient-centered medical home model in a county-based safety net system is possible and can reduce unnecessary ER use.

The CTBTO Link to the database of the International Seismological Centre (ISC)

NASA Astrophysics Data System (ADS)

Bondar, I.; Storchak, D. A.; Dando, B.; Harris, J.; Di Giacomo, D.

2011-12-01

The CTBTO Link to the database of the International Seismological Centre (ISC) is a project to provide access to seismological data sets maintained by the ISC using specially designed interactive tools. The Link is open to National Data Centres and to the CTBTO. By means of graphical interfaces and database queries tailored to the needs of the monitoring community, the users are given access to a multitude of products. These include the ISC and ISS bulletins, covering the seismicity of the Earth since 1904; nuclear and chemical explosions; the EHB bulletin; the IASPEI Reference Event list (ground truth database); and the IDC Reviewed Event Bulletin. The searches are divided into three main categories: The Area Based Search (a spatio-temporal search based on the ISC Bulletin), the REB search (a spatio-temporal search based on specific events in the REB) and the IMS Station Based Search (a search for historical patterns in the reports of seismic stations close to a particular IMS seismic station). The outputs are HTML based web-pages with a simplified version of the ISC Bulletin showing the most relevant parameters with access to ISC, GT, EHB and REB Bulletins in IMS1.0 format for single or multiple events. The CTBTO Link offers a tool to view REB events in context within the historical seismicity, look at observations reported by non-IMS networks, and investigate station histories and residual patterns for stations registered in the International Seismographic Station Registry.

An innovative Oklahoma program to coordinate interdisciplinary and interagency services for children with special healthcare needs at a county level.

PubMed

Wolraich, Mark; Lockhart, Jennifer; Worley, Louis

2013-03-01

Children and youth with special health care needs (CYSHCN) and their families often require multiple services from multiple providers in order to meet their needs. The Sooner SUCCESS (State Unified Children's Comprehensive Exemplary Services for Special Needs), was developed based on a complex adaptive systems approach allowing local coalitions to address their unique needs. Sooner SUCCESS provides support to families and service providers at the community level including a broad range of supports from simply helping a family identify and access a service that already exists to innovatively marshaling generic resources to meet a unique need. The program uses these family support activities coupled with the Community Needs Assessment to identify local service needs encouraging community capacity building by coordinating the efforts of the health, mental health, social and education systems to identify service gaps and develop community-based strategies to fill those gaps.

Sequencing of the large dsDNA genome of Oryctes rhinoceros nudivirus using multiple displacement amplification of nanogram amounts of virus DNA.

PubMed

Wang, Yongjie; Kleespies, Regina G; Ramle, Moslim B; Jehle, Johannes A

2008-09-01

The genomic sequence analysis of many large dsDNA viruses is hampered by the lack of enough sample materials. Here, we report a whole genome amplification of the Oryctes rhinoceros nudivirus (OrNV) isolate Ma07 starting from as few as about 10 ng of purified viral DNA by application of phi29 DNA polymerase- and exonuclease-resistant random hexamer-based multiple displacement amplification (MDA) method. About 60 microg of high molecular weight DNA with fragment sizes of up to 25 kbp was amplified. A genomic DNA clone library was generated using the product DNA. After 8-fold sequencing coverage, the 127,615 bp of OrNV whole genome was sequenced successfully. The results demonstrate that the MDA-based whole genome amplification enables rapid access to genomic information from exiguous virus samples.

Stigma as experienced by women accessing prevention of parent to child transmission of HIV services in Karnataka, India

PubMed Central

Rahangdale, Lisa; Banandur, Pradeep; Sreenivas, Amita; Turan, Janet; Washington, Reynold; Cohen, Craig R.

2010-01-01

In Karnataka, India only one-third of HIV-infected pregnant women received antiretroviral prophylaxis at delivery in 2007 through the state government’s prevention of parent-to-child HIV transmission (PPTCT) program. The current qualitative study explored the role of HIV-associated stigma as a barrier to accessing PPTCT services in the rural northern Karnataka district of Bagalkot using in depth interviews and focus group discussions with HIV-infected women who had participated in the PPTCT program, male and female family members, and HIV service providers. Participants discussed personal experiences, community perceptions of HIV, and decision-making related to accessing PPTCT services. They described stigma towards HIV-infected individuals from multiple sources: healthcare workers, community members, family and self. Stigma-related behaviors were based on fears of HIV transmission through personal contact and moral judgment. Experience and/or fears of discrimination led pregnant women to avoid using PPTCT interventions. Government, cultural and historical factors are described as the roots of much the stigma-related behavior in this setting. Based on these formative data, PPTCT program planners should consider further research and interventions aimed at diminishing institutional and interpersonal HIV-associated stigma experienced by pregnant women. PMID:20635247

Chesapeake Bay Program Water Quality Database

EPA Pesticide Factsheets

The Chesapeake Information Management System (CIMS), designed in 1996, is an integrated, accessible information management system for the Chesapeake Bay Region. CIMS is an organized, distributed library of information and software tools designed to increase basin-wide public access to Chesapeake Bay information. The information delivered by CIMS includes technical and public information, educational material, environmental indicators, policy documents, and scientific data. Through the use of relational databases, web-based programming, and web-based GIS a large number of Internet resources have been established. These resources include multiple distributed on-line databases, on-demand graphing and mapping of environmental data, and geographic searching tools for environmental information. Baseline monitoring data, summarized data and environmental indicators that document ecosystem status and trends, confirm linkages between water quality, habitat quality and abundance, and the distribution and integrity of biological populations are also available. One of the major features of the CIMS network is the Chesapeake Bay Program's Data Hub, providing users access to a suite of long- term water quality and living resources databases. Chesapeake Bay mainstem and tidal tributary water quality, benthic macroinvertebrates, toxics, plankton, and fluorescence data can be obtained for a network of over 800 monitoring stations.

MemAxes: Visualization and Analytics for Characterizing Complex Memory Performance Behaviors.

PubMed

Gimenez, Alfredo; Gamblin, Todd; Jusufi, Ilir; Bhatele, Abhinav; Schulz, Martin; Bremer, Peer-Timo; Hamann, Bernd

2018-07-01

Memory performance is often a major bottleneck for high-performance computing (HPC) applications. Deepening memory hierarchies, complex memory management, and non-uniform access times have made memory performance behavior difficult to characterize, and users require novel, sophisticated tools to analyze and optimize this aspect of their codes. Existing tools target only specific factors of memory performance, such as hardware layout, allocations, or access instructions. However, today's tools do not suffice to characterize the complex relationships between these factors. Further, they require advanced expertise to be used effectively. We present MemAxes, a tool based on a novel approach for analytic-driven visualization of memory performance data. MemAxes uniquely allows users to analyze the different aspects related to memory performance by providing multiple visual contexts for a centralized dataset. We define mappings of sampled memory access data to new and existing visual metaphors, each of which enabling a user to perform different analysis tasks. We present methods to guide user interaction by scoring subsets of the data based on known performance problems. This scoring is used to provide visual cues and automatically extract clusters of interest. We designed MemAxes in collaboration with experts in HPC and demonstrate its effectiveness in case studies.

Perceived Quality of Care of Community Health Worker and Facility-Based Health Worker Management of Pneumonia in Children Under 5 Years in Western Kenya: A Cross-Sectional Multidimensional Study

PubMed Central

Shaw, Brian I.; Asadhi, Elijah; Owuor, Kevin; Okoth, Peter; Abdi, Mohammed; Cohen, Craig R.; Onono, Maricianah

2016-01-01

Integrated community case management (iCCM) programs that train lay community health workers (CHWs) in the diagnosis and treatment of diarrhea, malaria, and pneumonia have been increasingly adopted throughout sub-Saharan Africa to provide services in areas where accessibility to formal public sector health services is low. One important aspect of successful iCCM programs is the acceptability and utilization of services provided by CHWs. To understand community perceptions of the quality of care in an iCCM intervention in western Kenya, we used the Primary Care Assessment Survey to compare caregiver attitudes about the diagnosis and treatment of childhood pneumonia as provided by CHWs and facility-based health workers (FBHWs). Overall, caregivers rated CHWs more highly than FBHWs across a set of 10 domains that capture multiple dimensions of the care process. Caregivers perceived CHWs to provide higher quality care in terms of accessibility and patient relationship and equal quality care on clinical aspects. These results argue for the continued implementation and scale-up of iCCM programs as an acceptable intervention for increasing access to treatment of childhood pneumonia. PMID:26976883

Web service activities at the IRIS DMC to support federated and multidisciplinary access

NASA Astrophysics Data System (ADS)

Trabant, Chad; Ahern, Timothy K.

2013-04-01

At the IRIS Data Management Center (DMC) we have developed a suite of web service interfaces to access our large archive of, primarily seismological, time series data and related metadata. The goals of these web services include providing: a) next-generation and easily used access interfaces for our current users, b) access to data holdings in a form usable for non-seismologists, c) programmatic access to facilitate integration into data processing workflows and d) a foundation for participation in federated data discovery and access systems. To support our current users, our services provide access to the raw time series data and metadata or conversions of the raw data to commonly used formats. Our services also support simple, on-the-fly signal processing options that are common first steps in many workflows. Additionally, high-level data products derived from raw data are available via service interfaces. To support data access by researchers unfamiliar with seismic data we offer conversion of the data to broadly usable formats (e.g. ASCII text) and data processing to convert the data to Earth units. By their very nature, web services are programmatic interfaces. Combined with ubiquitous support for web technologies in programming & scripting languages and support in many computing environments, web services are very well suited for integrating data access into data processing workflows. As programmatic interfaces that can return data in both discipline-specific and broadly usable formats, our services are also well suited for participation in federated and brokered systems either specific to seismology or multidisciplinary. Working within the International Federation of Digital Seismograph Networks, the DMC collaborated on the specification of standardized web service interfaces for use at any seismological data center. These data access interfaces, when supported by multiple data centers, will form a foundation on which to build discovery and access mechanisms for data sets spanning multiple centers. To promote the adoption of these standardized services the DMC has developed portable implementations of the software needed to host these interfaces, minimizing the work required at each data center. Within the COOPEUS project framework, the DMC is working with EU partners to install web services implementations at multiple data centers in Europe.

Network accessibility & the evoluation of urban employment.

DOT National Transportation Integrated Search

2011-06-01

This research examines the impact of accessibility on the growth of employment centers in the : Los Angeles Region between 1980 and 2000. There is extensive empirical documentation of : polycentricity the presence of multiple concentrations of em...

Job optimization in ATLAS TAG-based distributed analysis

NASA Astrophysics Data System (ADS)

Mambelli, M.; Cranshaw, J.; Gardner, R.; Maeno, T.; Malon, D.; Novak, M.

2010-04-01

The ATLAS experiment is projected to collect over one billion events/year during the first few years of operation. The efficient selection of events for various physics analyses across all appropriate samples presents a significant technical challenge. ATLAS computing infrastructure leverages the Grid to tackle the analysis across large samples by organizing data into a hierarchical structure and exploiting distributed computing to churn through the computations. This includes events at different stages of processing: RAW, ESD (Event Summary Data), AOD (Analysis Object Data), DPD (Derived Physics Data). Event Level Metadata Tags (TAGs) contain information about each event stored using multiple technologies accessible by POOL and various web services. This allows users to apply selection cuts on quantities of interest across the entire sample to compile a subset of events that are appropriate for their analysis. This paper describes new methods for organizing jobs using the TAGs criteria to analyze ATLAS data. It further compares different access patterns to the event data and explores ways to partition the workload for event selection and analysis. Here analysis is defined as a broader set of event processing tasks including event selection and reduction operations ("skimming", "slimming" and "thinning") as well as DPD making. Specifically it compares analysis with direct access to the events (AOD and ESD data) to access mediated by different TAG-based event selections. We then compare different ways of splitting the processing to maximize performance.

Multiple barriers to participation for people with psychosocial disability in Dehradun district, North India: a cross-sectional study.

PubMed

Mathias, Kaaren; Pant, Hira; Marella, Manjula; Singh, Lawrence; Murthy, Gvs; Grills, Nathan

2018-02-27

This study used a population-based cross-sectional survey to describe the prevalence of psychosocial disability and unmet need for access to services in North India. This study was conducted in Dehradun district, Uttarakhand, in 2014. A population-based sample of 2441 people over the age of 18 years. The Rapid Assessment of Disability survey tool identified people with disability and used an adapted version of the Kessler scale to identify those with psychosocial disability. It additionally collected information on socioeconomic variables, access to community services and barriers to participation. Prevalence of psychosocial disability and unmet needs and descriptions of barriers to services were calculated, and multivariable logistic regression was used to assess associations between risk factors and psychosocial disability. Prevalence of psychosocial disability was 4.8% and 75% of participants with psychological distress also reported comorbid functional impairments. Adjusted ORs for depression of more than two were found for people who were unschooled, unemployed and of moderate or poor socioeconomic status. The unmet need for access to services was significantly higher in every domain for people with psychosocial disability and was more than 25% in the areas of employment, health service access and community consultation. People with psychosocial disability encountered greater barriers in each domain compared with controls. People who are poor, uneducated and unemployed are two to four times more likely to have psychosocial disability in Dehradun district. They face unmet needs in accessing community services and perceive negative social attitudes, lack of physical accessibility and lack of information as barriers limiting their participation. Social policy must increase access to education and reduce poverty but additionally ensure action is taken in all community services to increase information, physical accessibility and social inclusion of people with psychosocial and other forms of disability. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

A New Aloha Anti-Collision Algorithm Based on CDMA

NASA Astrophysics Data System (ADS)

Bai, Enjian; Feng, Zhu

The tags' collision is a common problem in RFID (radio frequency identification) system. The problem has affected the integrity of the data transmission during the process of communication in the RFID system. Based on analysis of the existing anti-collision algorithm, a novel anti-collision algorithm is presented. The new algorithm combines the group dynamic frame slotted Aloha algorithm with code division multiple access technology. The algorithm can effectively reduce the collision probability between tags. Under the same number of tags, the algorithm is effective in reducing the reader recognition time and improve overall system throughput rate.

service line analytics in the new era.

PubMed

Spence, Jay; Seargeant, Dan

2015-08-01

To succeed under the value-based business model, hospitals and health systems require effective service line analytics that combine inpatient and outpatient data and that incorporate quality metrics for evaluating clinical operations. When developing a framework for collection, analysis, and dissemination of service line data, healthcare organizations should focus on five key aspects of effective service line analytics: Updated service line definitions. Ability to analyze and trend service line net patient revenues by payment source. Access to accurate service line cost information across multiple dimensions with drill-through capabilities. Ability to redesign key reports based on changing requirements. Clear assignment of accountability.

Multiple Determinants, Common Vulnerabilities, and Creative Responses: Addressing the AIDS Pandemic in Diverse Populations Globally

PubMed Central

Mayer, Kenneth H.; Pape, Jean William; Wilson, Phill; Diallo, Dazon Dixon; Saavedra, Jorge; Mimiaga, Matthew J.; Koenig, Serena; Farmer, Paul

2012-01-01

The AIDS epidemic has been fueled by global inequities. Ranging from gender inequality and underdevelopment to homophobia impeding health care access for men who have sex with men (MSM), imbalanced resource allocations and social biases have potentiated the epidemic’s spread. However, recognition of culturally specific aspects of each microepidemic has yielded development of community-based organizations, which have resulted in locally effective responses to AIDS. This effective approach to HIV prevention, care and treatment is illustrated through examples of community-based responses in Haiti, the United States, Africa, and other impoverished settings. PMID:22772387

A physical layer perspective on access network sharing

NASA Astrophysics Data System (ADS)

Pfeiffer, Thomas

2015-12-01

Unlike in copper or wireless networks, there is no sharing of resources in fiber access networks yet, other than bit stream access or cable sharing, in which the fibers of a cable are let to one or multiple operators. Sharing optical resources on a single fiber among multiple operators or different services has not yet been applied. While this would allow for a better exploitation of installed infrastructures, there are operational issues which still need to be resolved, before this sharing model can be implemented in networks. Operating multiple optical systems and services over a common fiber plant, autonomously and independently from each other, can result in mutual distortions on the physical layer. These distortions will degrade the performance of the involved systems, unless precautions are taken in the infrastructure hardware to eliminate or to reduce them to an acceptable level. Moreover, the infrastructure needs to be designed such as to support different system technologies and to ensure a guaranteed quality of the end-to-end connections. In this paper, suitable means are proposed to be introduced in fiber access infrastructures that will allow for shared utilization of the fibers while safeguarding the operational needs and business interests of the involved parties.

What versus where: Investigating how autobiographical memory retrieval differs when accessed with thematic versus spatial information.

PubMed

Sheldon, Signy; Chu, Sonja

2017-09-01

Autobiographical memory research has investigated how cueing distinct aspects of a past event can trigger different recollective experiences. This research has stimulated theories about how autobiographical knowledge is accessed and organized. Here, we test the idea that thematic information organizes multiple autobiographical events whereas spatial information organizes individual past episodes by investigating how retrieval guided by these two forms of information differs. We used a novel autobiographical fluency task in which participants accessed multiple memory exemplars to event theme and spatial (location) cues followed by a narrative description task in which they described the memories generated to these cues. Participants recalled significantly more memory exemplars to event theme than to spatial cues; however, spatial cues prompted faster access to past memories. Results from the narrative description task revealed that memories retrieved via event theme cues compared to spatial cues had a higher number of overall details, but those recalled to the spatial cues were recollected with a greater concentration on episodic details than those retrieved via event theme cues. These results provide evidence that thematic information organizes and integrates multiple memories whereas spatial information prompts the retrieval of specific episodic content from a past event.

Managing data from multiple disciplines, scales, and sites to support synthesis and modeling

USGS Publications Warehouse

Olson, R. J.; Briggs, J. M.; Porter, J.H.; Mah, Grant R.; Stafford, S.G.

1999-01-01

The synthesis and modeling of ecological processes at multiple spatial and temporal scales involves bringing together and sharing data from numerous sources. This article describes a data and information system model that facilitates assembling, managing, and sharing diverse data from multiple disciplines, scales, and sites to support integrated ecological studies. Cross-site scientific-domain working groups coordinate the development of data associated with their particular scientific working group, including decisions about data requirements, data to be compiled, data formats, derived data products, and schedules across the sites. The Web-based data and information system consists of nodes for each working group plus a central node that provides data access, project information, data query, and other functionality. The approach incorporates scientists and computer experts in the working groups and provides incentives for individuals to submit documented data to the data and information system.

Secure multiple access for indoor optical wireless communications with time-slot coding and chaotic phase.

PubMed

Liang, Tian; Wang, Ke; Lim, Christina; Wong, Elaine; Song, Tingting; Nirmalathas, Ampalavanapillai

2017-09-04

In this paper, we report a novel mechanism to simultaneously provide secure connections for multiple users in indoor optical wireless communication systems by employing the time-slot coding scheme together with chaotic phase sequence. The chaotic phase sequence is generated according to the logistic map and applied to each symbol to secure the transmission. Proof-of-concept experiments are carried out for multiple system capacities based on both 4-QAM and 16-QAM modulation formats, i.e. 1.25 Gb/s, 2 Gb/s and 2.5 Gb/s for 4-QAM, and 2.5 Gb/s, 3.33 Gb/s and 4 Gb/s for 16-QAM. Experimental results show that in all cases the added chaotic phase does not degrade the legitimate user's signal quality while the illegal user cannot detect the signal without the key.

Nonadditivity of quantum and classical capacities for entanglement breaking multiple-access channels and the butterfly network

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grudka, Andrzej; National Quantum Information Centre of Gdansk, PL-81-824 Sopot; Horodecki, Pawel

2010-06-15

We analyze quantum network primitives which are entanglement breaking. We show superadditivity of quantum and classical capacity regions for quantum multiple-access channels and the quantum butterfly network. Since the effects are especially visible at high noise they suggest that quantum information effects may be particularly helpful in the case of the networks with occasional high noise rates. The present effects provide a qualitative borderline between superadditivities of bipartite and multipartite systems.

Code division multiple access signaling for modulated reflector technology

DOEpatents

Briles, Scott D [Los Alamos, NM

2012-05-01

A method and apparatus for utilizing code division multiple access in modulated reflectance transmissions comprises the steps of generating a phase-modulated reflectance data bit stream; modifying the modulated reflectance data bit stream; providing the modified modulated reflectance data bit stream to a switch that connects an antenna to an infinite impedance in the event a "+1" is to be sent, or connects the antenna to ground in the event a "0" or a "-1" is to be sent.

Web-based access to near real-time and archived high-density time-series data: cyber infrastructure challenges & developments in the open-source Waveform Server

NASA Astrophysics Data System (ADS)

Reyes, J. C.; Vernon, F. L.; Newman, R. L.; Steidl, J. H.

2010-12-01

The Waveform Server is an interactive web-based interface to multi-station, multi-sensor and multi-channel high-density time-series data stored in Center for Seismic Studies (CSS) 3.0 schema relational databases (Newman et al., 2009). In the last twelve months, based on expanded specifications and current user feedback, both the server-side infrastructure and client-side interface have been extensively rewritten. The Python Twisted server-side code-base has been fundamentally modified to now present waveform data stored in cluster-based databases using a multi-threaded architecture, in addition to supporting the pre-existing single database model. This allows interactive web-based access to high-density (broadband @ 40Hz to strong motion @ 200Hz) waveform data that can span multiple years; the common lifetime of broadband seismic networks. The client-side interface expands on it's use of simple JSON-based AJAX queries to now incorporate a variety of User Interface (UI) improvements including standardized calendars for defining time ranges, applying on-the-fly data calibration to display SI-unit data, and increased rendering speed. This presentation will outline the various cyber infrastructure challenges we have faced while developing this application, the use-cases currently in existence, and the limitations of web-based application development.

Data-Driven Identification of Structural Alerts for Mitigating the Risk of Drug-Induced Human Liver Injuries

DTIC Science & Technology

2015-02-11

the National Library of Medicine of the U.S. National Institutes of Health launched LiverTox, a data- base of ~700 medications associated with human... herbal remedies, and dietary supplements. Carefully curated and reviewed by experts in multiple disciplines, the database constitutes a valu- able resource...March 2014 via web access at http://livertox.nih.gov/. We then removed entries without chemical structures, such as some herbal extracts and vac

Experiments with a Knowledge-Based System on a Multiprocessor

DTIC Science & Technology

1987-10-01

variables on the node. Functions have access to those instance variables. Gajski et. al. [ Gajski 82] summarize the principles underlying pure data flow...ConSider the following numerical example from Gajski et. al. ( Gajski 82]. The pseudo-code representation of the problem is as follows: co - 0 A=x £ 1 Ixo... Gajski et. al. They assume that division takes three processing units, multiplication takes two units, and addition takes one unit. As noted in their paper

PmiRExAt: plant miRNA expression atlas database and web applications

PubMed Central

Gurjar, Anoop Kishor Singh; Panwar, Abhijeet Singh; Gupta, Rajinder; Mantri, Shrikant S.

2016-01-01

High-throughput small RNA (sRNA) sequencing technology enables an entirely new perspective for plant microRNA (miRNA) research and has immense potential to unravel regulatory networks. Novel insights gained through data mining in publically available rich resource of sRNA data will help in designing biotechnology-based approaches for crop improvement to enhance plant yield and nutritional value. Bioinformatics resources enabling meta-analysis of miRNA expression across multiple plant species are still evolving. Here, we report PmiRExAt, a new online database resource that caters plant miRNA expression atlas. The web-based repository comprises of miRNA expression profile and query tool for 1859 wheat, 2330 rice and 283 maize miRNA. The database interface offers open and easy access to miRNA expression profile and helps in identifying tissue preferential, differential and constitutively expressing miRNAs. A feature enabling expression study of conserved miRNA across multiple species is also implemented. Custom expression analysis feature enables expression analysis of novel miRNA in total 117 datasets. New sRNA dataset can also be uploaded for analysing miRNA expression profiles for 73 plant species. PmiRExAt application program interface, a simple object access protocol web service allows other programmers to remotely invoke the methods written for doing programmatic search operations on PmiRExAt database. Database URL: http://pmirexat.nabi.res.in. PMID:27081157

Carrier Estimation Using Classic Spectral Estimation Techniques for the Proposed Demand Assignment Multiple Access Service

NASA Technical Reports Server (NTRS)

Scaife, Bradley James

1999-01-01

In any satellite communication, the Doppler shift associated with the satellite's position and velocity must be calculated in order to determine the carrier frequency. If the satellite state vector is unknown then some estimate must be formed of the Doppler-shifted carrier frequency. One elementary technique is to examine the signal spectrum and base the estimate on the dominant spectral component. If, however, the carrier is spread (as in most satellite communications) this technique may fail unless the chip rate-to-data rate ratio (processing gain) associated with the carrier is small. In this case, there may be enough spectral energy to allow peak detection against a noise background. In this thesis, we present a method to estimate the frequency (without knowledge of the Doppler shift) of a spread-spectrum carrier assuming a small processing gain and binary-phase shift keying (BPSK) modulation. Our method relies on an averaged discrete Fourier transform along with peak detection on spectral match filtered data. We provide theory and simulation results indicating the accuracy of this method. In addition, we will describe an all-digital hardware design based around a Motorola DSP56303 and high-speed A/D which implements this technique in real-time. The hardware design is to be used in NMSU's implementation of NASA's demand assignment, multiple access (DAMA) service.

Interference-free SDMA for FBMC-OQAM

NASA Astrophysics Data System (ADS)

Horlin, François; Fickers, Jessica; Deleu, Thibault; Louveaux, Jérome

2013-12-01

Filter-bank multi-carrier (FBMC) modulations have recently been considered for the emerging wireless communication systems as a means to improve the utilization of the physical resources and the robustness to channel time variations. FBMC divides the overall frequency channel in a set of subchannels of bandwidth proportionally decreasing with the number of subchannels. If the number of subchannels is high enough, the bandwidth of each subchannel is small enough to assume that it is approximately flat. On the other hand, space-division multiple access (SDMA) is a recognized technique to support multiple access in the downlink of a multi-user system. The user signals are precoded at the base station equipped with multiple antennas to separate the users in the spatial domain. The application of SDMA to FBMC is unfortunately difficult when the channel is too frequency selective (or when the number of subchannels to too small) to assume flat subchannels. In that case, the system suffers from inter-symbol and inter-subchannel interference, besides the multi-user interference inherent to SDMA. State-of-the art solutions simply neglect the inter-symbol/subchannel interference. This article proposes a new SDMA precoder for FBMC capable of mitigating the three sources of interference. It is constructed per subchannel in order to keep an acceptable complexity and has the structure of a filter applied on each subchannel and its neighbors at twice the symbol rate. Numerical results demonstrate that the precoder can get rid of all the interference present in the system and benefit therefore from the diversity and power gains achievable with multiple antenna systems.

Remote eye care screening for rural veterans with Technology-based Eye Care Services: a quality improvement project.

PubMed

Maa, April Y; Wojciechowski, Barbara; Hunt, Kelly; Dismuke, Clara; Janjua, Rabeea; Lynch, Mary G

2017-01-01

Veterans are at high risk for eye disease because of age and comorbid conditions. Access to eye care is challenging within the entire Veterans Hospital Administration's network of hospitals and clinics in the USA because it is the third busiest outpatient clinical service and growing at a rate of 9% per year. Rural and highly rural veterans face many more barriers to accessing eye care because of distance, cost to travel, and difficulty finding care in the community as many live in medically underserved areas. Also, rural veterans may be diagnosed in later stages of eye disease than their non-rural counterparts due to lack of access to specialty care. In March 2015, Technology-based Eye Care Services (TECS) was launched from the Atlanta Veterans Affairs (VA) as a quality improvement project to provide eye screening services for rural veterans. By tracking multiple measures including demographic and access to care metrics, data shows that TECS significantly improved access to care, with 33% of veterans receiving same-day access and >98% of veterans receiving an appointment within 30 days of request. TECS also provided care to a significant percentage of homeless veterans, 10.6% of the patients screened. Finally, TECS reduced healthcare costs, saving the VA up to US$148 per visit and approximately US$52 per patient in round trip travel reimbursements when compared to completing a face-to-face exam at the medical center. Overall savings to the VA system in this early phase of TECS totaled US$288,400, about US$41,200 per month. Other healthcare facilities may be able to use a similar protocol to extend care to at-risk patients.

Internet-based profiler system as integrative framework to support translational research

PubMed Central

Kim, Robert; Demichelis, Francesca; Tang, Jeffery; Riva, Alberto; Shen, Ronglai; Gibbs, Doug F; Mahavishno, Vasudeva; Chinnaiyan, Arul M; Rubin, Mark A

2005-01-01

Background Translational research requires taking basic science observations and developing them into clinically useful tests and therapeutics. We have developed a process to develop molecular biomarkers for diagnosis and prognosis by integrating tissue microarray (TMA) technology and an internet-database tool, Profiler. TMA technology allows investigators to study hundreds of patient samples on a single glass slide resulting in the conservation of tissue and the reduction in inter-experimental variability. The Profiler system allows investigator to reliably track, store, and evaluate TMA experiments. Here within we describe the process that has evolved through an empirical basis over the past 5 years at two academic institutions. Results The generic design of this system makes it compatible with multiple organ system (e.g., prostate, breast, lung, renal, and hematopoietic system,). Studies and folders are restricted to authorized users as required. Over the past 5 years, investigators at 2 academic institutions have scanned 656 TMA experiments and collected 63,311 digital images of these tissue samples. 68 pathologists from 12 major user groups have accessed the system. Two groups directly link clinical data from over 500 patients for immediate access and the remaining groups choose to maintain clinical and pathology data on separate systems. Profiler currently has 170 K data points such as staining intensity, tumor grade, and nuclear size. Due to the relational database structure, analysis can be easily performed on single or multiple TMA experimental results. The TMA module of Profiler can maintain images acquired from multiple systems. Conclusion We have developed a robust process to develop molecular biomarkers using TMA technology and an internet-based database system to track all steps of this process. This system is extendable to other types of molecular data as separate modules and is freely available to academic institutions for licensing. PMID:16364175

Enhancing a Teen Pregnancy Prevention Program with text messaging: engaging minority youth to develop TOP ® Plus Text.

PubMed

Devine, Sharon; Bull, Sheana; Dreisbach, Susan; Shlay, Judith

2014-03-01

To develop and pilot a theory-based, mobile phone texting component attractive to minority youth as a supplement to the Teen Outreach Program(®), a youth development program for reducing teen pregnancy and school dropout. We conducted iterative formative research with minority youth in multiple focus groups to explore interest in texting and reaction to text messages. We piloted a month-long version of TOP(®) Plus Text with 96 teens at four sites and conducted a computer-based survey immediately after enrollment and at the end of the pilot that collected information about teens' values, social support, self-efficacy, and behaviors relating to school performance, trouble with the law, and sexual activity. After each of the first three weekly sessions we collected satisfaction measures. Upon completion of the pilot we conducted exit interviews with twelve purposively selected pilot participants. We successfully recruited and enrolled minority youth into the pilot. Teens were enthusiastic about text messages complementing TOP(®). Results also revealed barriers: access to text-capable mobile phones, retention as measured by completion of the post-pilot survey, and a need to be attentive to teen literacy. Piloting helped identify improvements for implementation including offering text messages through multiple platforms so youth without access to a mobile phone could receive messages; rewording texts to allow youth to express opinions without feeling judged; and collecting multiple types of contact information to improve follow-up. Thoughtful attention to social and behavioral theory and investment in iterative formative research with extensive consultation with teens can lead to an engaging texting curriculum that enhances and complements TOP(®). Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Internet-based Profiler system as integrative framework to support translational research.

PubMed

Kim, Robert; Demichelis, Francesca; Tang, Jeffery; Riva, Alberto; Shen, Ronglai; Gibbs, Doug F; Mahavishno, Vasudeva; Chinnaiyan, Arul M; Rubin, Mark A

2005-12-19

Translational research requires taking basic science observations and developing them into clinically useful tests and therapeutics. We have developed a process to develop molecular biomarkers for diagnosis and prognosis by integrating tissue microarray (TMA) technology and an internet-database tool, Profiler. TMA technology allows investigators to study hundreds of patient samples on a single glass slide resulting in the conservation of tissue and the reduction in inter-experimental variability. The Profiler system allows investigator to reliably track, store, and evaluate TMA experiments. Here within we describe the process that has evolved through an empirical basis over the past 5 years at two academic institutions. The generic design of this system makes it compatible with multiple organ system (e.g., prostate, breast, lung, renal, and hematopoietic system,). Studies and folders are restricted to authorized users as required. Over the past 5 years, investigators at 2 academic institutions have scanned 656 TMA experiments and collected 63,311 digital images of these tissue samples. 68 pathologists from 12 major user groups have accessed the system. Two groups directly link clinical data from over 500 patients for immediate access and the remaining groups choose to maintain clinical and pathology data on separate systems. Profiler currently has 170 K data points such as staining intensity, tumor grade, and nuclear size. Due to the relational database structure, analysis can be easily performed on single or multiple TMA experimental results. The TMA module of Profiler can maintain images acquired from multiple systems. We have developed a robust process to develop molecular biomarkers using TMA technology and an internet-based database system to track all steps of this process. This system is extendable to other types of molecular data as separate modules and is freely available to academic institutions for licensing.

System Design and Cataloging Meet the User: User Interfaces to Online Public Access Catalogs.

ERIC Educational Resources Information Center

Yee, Martha M.

1991-01-01

Discusses features of online public access catalogs: (1) demonstration of relationships between records; (2) provision of entry vocabularies; (3) arrangement of multiple entries on the screen; (4) provision of access points; (5) display of single records; and (6) division of catalogs into separate files or indexes. User studies and other research…

Action Research to Improve Methods of Delivery and Feedback in an Access Grid Room Environment

ERIC Educational Resources Information Center

McArthur, Lynne C.; Klass, Lara; Eberhard, Andrew; Stacey, Andrew

2011-01-01

This article describes a qualitative study which was undertaken to improve the delivery methods and feedback opportunity in honours mathematics lectures which are delivered through Access Grid Rooms. Access Grid Rooms are facilities that provide two-way video and audio interactivity across multiple sites, with the inclusion of smart boards. The…

Global access to surgical care: a modelling study.

PubMed

Alkire, Blake C; Raykar, Nakul P; Shrime, Mark G; Weiser, Thomas G; Bickler, Stephen W; Rose, John A; Nutt, Cameron T; Greenberg, Sarah L M; Kotagal, Meera; Riesel, Johanna N; Esquivel, Micaela; Uribe-Leitz, Tarsicio; Molina, George; Roy, Nobhojit; Meara, John G; Farmer, Paul E

2015-06-01

More than 2 billion people are unable to receive surgical care based on operating theatre density alone. The vision of the Lancet Commission on Global Surgery is universal access to safe, affordable surgical and anaesthesia care when needed. We aimed to estimate the number of individuals worldwide without access to surgical services as defined by the Commission's vision. We modelled access to surgical services in 196 countries with respect to four dimensions: timeliness, surgical capacity, safety, and affordability. We built a chance tree for each country to model the probability of surgical access with respect to each dimension, and from this we constructed a statistical model to estimate the proportion of the population in each country that does not have access to surgical services. We accounted for uncertainty with one-way sensitivity analyses, multiple imputation for missing data, and probabilistic sensitivity analysis. At least 4·8 billion people (95% posterior credible interval 4·6-5·0 [67%, 64-70]) of the world's population do not have access to surgery. The proportion of the population without access varied widely when stratified by epidemiological region: greater than 95% of the population in south Asia and central, eastern, and western sub-Saharan Africa do not have access to care, whereas less than 5% of the population in Australasia, high-income North America, and western Europe lack access. Most of the world's population does not have access to surgical care, and access is inequitably distributed. The near absence of access in many low-income and middle-income countries represents a crisis, and as the global health community continues to support the advancement of universal health coverage, increasing access to surgical services will play a central role in ensuring health care for all. None. Copyright © 2015 Alkire et al. Open Access article distributed under the terms of CC BY. Published by Elsevier Ltd.. All rights reserved.

Improving Global Access to New Vaccines: Intellectual Property, Technology Transfer, and Regulatory Pathways

PubMed Central

2014-01-01

The 2012 World Health Assembly Global Vaccine Action Plan called for global access to new vaccines within 5 years of licensure. Current approaches have proven insufficient to achieve sustainable vaccine pricing within such a timeline. Paralleling the successful strategy of generic competition to bring down drug prices, a clear consensus is emerging that market entry of multiple suppliers is a critical factor in expeditiously bringing down prices of new vaccines. In this context, key target objectives for improving access to new vaccines include overcoming intellectual property obstacles, streamlining regulatory pathways for biosimilar vaccines, and reducing market entry timelines for developing-country vaccine manufacturers by transfer of technology and know-how. I propose an intellectual property, technology, and know-how bank as a new approach to facilitate widespread access to new vaccines in low- and middle-income countries by efficient transfer of patented vaccine technologies to multiple developing-country vaccine manufacturers. PMID:25211753

Improving global access to new vaccines: intellectual property, technology transfer, and regulatory pathways.

PubMed

Crager, Sara Eve

2014-11-01

The 2012 World Health Assembly Global Vaccine Action Plan called for global access to new vaccines within 5 years of licensure. Current approaches have proven insufficient to achieve sustainable vaccine pricing within such a timeline. Paralleling the successful strategy of generic competition to bring down drug prices, a clear consensus is emerging that market entry of multiple suppliers is a critical factor in expeditiously bringing down prices of new vaccines. In this context, key target objectives for improving access to new vaccines include overcoming intellectual property obstacles, streamlining regulatory pathways for biosimilar vaccines, and reducing market entry timelines for developing-country vaccine manufacturers by transfer of technology and know-how. I propose an intellectual property, technology, and know-how bank as a new approach to facilitate widespread access to new vaccines in low- and middle-income countries by efficient transfer of patented vaccine technologies to multiple developing-country vaccine manufacturers.

[Improving global access to new vaccines: intellectual property, technology transfer, and regulatory pathways].

PubMed

Crager, Sara Eve

2015-01-01

The 2012 World Health Assembly Global Vaccine Action Plan called for global access to new vaccines within 5 years of licensure. Current approaches have proven insufficient to achieve sustainable vaccine pricing within such a timeline. Paralleling the successful strategy of generic competition to bring down drug prices, a clear consensus is emerging that market entry of multiple suppliers is a critical factor in expeditiously bringing down prices of new vaccines. In this context, key target objectives for improving access to new vaccines include overcoming intellectual property obstacles, streamlining regulatory pathways for biosimilar vaccines, and reducing market entry timelines for developing-country vaccine manufacturers by transfer of technology and know-how. I propose an intellectual property, technology, and know-how bank as a new approach to facilitate widespread access to new vaccines in low- and middle-income countries by efficient transfer of patented vaccine technologies to multiple developing-country vaccine manufacturers.

An Educational Rationale for Deaf Students with Multiple Disabilities

ERIC Educational Resources Information Center

Ewing, Karen M.; Jones, Thomas W.

2003-01-01

Deaf students with multiple disabilities have a long history of limited opportunity, including limited access to educational opportunities available to their deaf peers. This article places the individual needs of deaf students with multiple disabilities in the context that guides much of deaf education--the importance of language acquisition.…

Analysis of practical backoff protocols for contention resolution with multiple servers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goldberg, L.A.; MacKenzie, P.D.

Backoff protocols are probably the most widely used protocols for contention resolution in multiple access channels. In this paper, we analyze the stochastic behavior of backoff protocols for contention resolution among a set of clients and servers, each server being a multiple access channel that deals with contention like an Ethernet channel. We use the standard model in which each client generates requests for a given server according to a Bemoulli distribution with a specified mean. The client-server request rate of a system is the maximum over all client-server pairs (i, j) of the sum of all request rates associatedmore » with either client i or server j. Our main result is that any superlinear polynomial backoff protocol is stable for any multiple-server system with a sub-unit client-server request rate. We confirm the practical relevance of our result by demonstrating experimentally that the average waiting time of requests is very small when such a system is run with reasonably few clients and reasonably small request rates such as those that occur in actual ethernets. Our result is the first proof of stability for any backoff protocol for contention resolution with multiple servers. Our result is also the first proof that any weakly acknowledgment based protocol is stable for contention resolution with multiple servers and such high request rates. Two special cases of our result are of interest. Hastad, Leighton and Rogoff have shown that for a single-server system with a sub-unit client-server request rate any modified superlinear polynomial backoff protocol is stable. These modified backoff protocols are similar to standard backoff protocols but require more random bits to implement. The special case of our result in which there is only one server extends the result of Hastad, Leighton and Rogoff to standard (practical) backoff protocols. Finally, our result applies to dynamic routing in optical networks.« less

An integrated voice and data multiple-access scheme for a land-mobile satellite system

NASA Technical Reports Server (NTRS)

Li, V. O. K.; Yan, T.-Y.

1984-01-01

An analytical study is performed of the satellite requirements for a land mobile satellite system (LMSS). The spacecraft (MSAT-X) would be in GEO and would be compatible with multiple access by mobile radios and antennas and fixed stations. The FCC has received a petition from NASA to reserve the 821-825 and 866-870 MHz frequencies for the LMSS, while communications with fixed earth stations would be in the Ku band. MSAT-X transponders would alter the frequencies of signal and do no processing in the original configuration considered. Channel use would be governed by an integrated demand-assigned, multiple access protocol, which would divide channels into reservation and information channels, governed by a network management center. Further analyses will cover tradeoffs between data and voice users, probability of blocking, and the performance impacts of on-board switching and variable bandwidth assignment. Initial calculations indicate that a large traffic volume can be handled with acceptable delays and voice blocking probabilities.

An integrated voice and data multiple-access scheme for a land-mobile satellite system

NASA Astrophysics Data System (ADS)

Li, V. O. K.; Yan, T.-Y.

1984-11-01

An analytical study is performed of the satellite requirements for a land mobile satellite system (LMSS). The spacecraft (MSAT-X) would be in GEO and would be compatible with multiple access by mobile radios and antennas and fixed stations. The FCC has received a petition from NASA to reserve the 821-825 and 866-870 MHz frequencies for the LMSS, while communications with fixed earth stations would be in the Ku band. MSAT-X transponders would alter the frequencies of signal and do no processing in the original configuration considered. Channel use would be governed by an integrated demand-assigned, multiple access protocol, which would divide channels into reservation and information channels, governed by a network management center. Further analyses will cover tradeoffs between data and voice users, probability of blocking, and the performance impacts of on-board switching and variable bandwidth assignment. Initial calculations indicate that a large traffic volume can be handled with acceptable delays and voice blocking probabilities.

User needs for propagation data

NASA Technical Reports Server (NTRS)

Sullivan, Thomas M.

1993-01-01

New and refined models of radio signal propagation phenomena are needed to support studies of evolving satellite services and systems. Taking an engineering perspective, applications for propagation measurements and models in the context of various types of analyses that are of ongoing interest are reviewed. Problems that were encountered in the signal propagation aspects of these analyses are reviewed, and potential solutions to these problems are discussed. The focus is on propagation measurements and models needed to support design and performance analyses of systems in the Mobile-Satellite Service (MSS) operating in the 1-3 GHz range. These systems may use geostationary or non-geostationary satellites and Frequency Division Multiple Access (FDMA), Time Division Multiple Access Digital (TDMA), or Code Division Multiple Access (CDMA) techniques. Many of the propagation issues raised in relation to MSS are also pertinent to other services such as broadcasting-satellite (sound) at 2310-2360 MHz. In particular, services involving mobile terminals or terminals with low gain antennas are of concern.

Transparent data service with multiple wireless access

NASA Technical Reports Server (NTRS)

Dean, Richard A.; Levesque, Allen H.

1993-01-01

The rapid introduction of digital wireless networks is an important part of the emerging digital communications scene. The introduction of Digital Cellular, LEO and GEO Satellites, and Personal Communications Services poses both a challenge and an opportunity for the data user. On the one hand wireless access will introduce significant new portable data services such as personal notebooks, paging, E-mail, and fax that will put the information age in the user's pocket. On the other hand the challenge of creating a seamless and transparent environment for the user in multiple access environments and across multiple network connections is formidable. A summary of the issues associated with developing techniques and standards that can support transparent and seamless data services is presented. The introduction of data services into the radio world represents a unique mix of RF channel problems, data protocol issues, and network issues. These problems require that experts from each of these disciplines fuse the individual technologies to support these services.

Network issues for large mass storage requirements

NASA Technical Reports Server (NTRS)

Perdue, James

1992-01-01

File Servers and Supercomputing environments need high performance networks to balance the I/O requirements seen in today's demanding computing scenarios. UltraNet is one solution which permits both high aggregate transfer rates and high task-to-task transfer rates as demonstrated in actual tests. UltraNet provides this capability as both a Server-to-Server and Server-to-Client access network giving the supercomputing center the following advantages highest performance Transport Level connections (to 40 MBytes/sec effective rates); matches the throughput of the emerging high performance disk technologies, such as RAID, parallel head transfer devices and software striping; supports standard network and file system applications using SOCKET's based application program interface such as FTP, rcp, rdump, etc.; supports access to the Network File System (NFS) and LARGE aggregate bandwidth for large NFS usage; provides access to a distributed, hierarchical data server capability using DISCOS UniTree product; supports file server solutions available from multiple vendors, including Cray, Convex, Alliant, FPS, IBM, and others.

Living as an LGBTQ adolescent and a parent’s child: Overlapping or separate experiences

PubMed Central

Watson, Ryan J.; Eisenberg, Marla E.; Corliss, Heather L.; Porta, Carolyn M.

2017-01-01

It is well known that parental and community-based support are each related to healthy development in LGBTQ youth, but little research has explored the ways these contexts interact and overlap. Through go-along interviews (a method in which participants guide the interviewer around the community) with 66 youth in British Columbia, Massachusetts, and Minnesota, adolescents (aged 14–19 years) reported varying extent of overlap between their LGBTQ experiences and their parent-youth experiences; parents and youth each contributed to the extent of overlap. Youth who reported high overlap reported little need for resources outside their families but found resources easy to access if wanted. Youth who reported little overlap found it difficult to access resources. Findings suggest that in both research and practice, considering the extent to which youth feel they can express their authentic identity in multiple contexts may be more useful than simply evaluating parental acceptance or access to resources. PMID:28795897

Living as an LGBTQ Adolescent and a Parent's Child: Overlapping or Separate Experiences.

PubMed

Mehus, Christopher J; Watson, Ryan J; Eisenberg, Marla E; Corliss, Heather L; Porta, Carolyn M

2017-05-01

It is well known that parental and community-based support are each related to healthy development in lesbian, gay, bisexual, transgender, queer, and questioning (LGBTQ) youth, but little research has explored the ways these contexts interact and overlap. Through go-along interviews (a method in which participants guide the interviewer around the community) with 66 youth in British Columbia, Massachusetts, and Minnesota, adolescents (aged 14-19 years) reported varying extent of overlap between their LGBTQ experiences and their parent-youth experiences; parents and youth each contributed to the extent of overlap. Youth who reported high overlap reported little need for resources outside their families but found resources easy to access if wanted. Youth who reported little overlap found it difficult to access resources. Findings suggest that in both research and practice, considering the extent to which youth feel they can express their authentic identity in multiple contexts may be more useful than simply evaluating parental acceptance or access to resources.

Similarity searching and scaffold hopping in synthetically accessible combinatorial chemistry spaces.

PubMed

Boehm, Markus; Wu, Tong-Ying; Claussen, Holger; Lemmen, Christian

2008-04-24

Large collections of combinatorial libraries are an integral element in today's pharmaceutical industry. It is of great interest to perform similarity searches against all virtual compounds that are synthetically accessible by any such library. Here we describe the successful application of a new software tool CoLibri on 358 combinatorial libraries based on validated reaction protocols to create a single chemistry space containing over 10 (12) possible products. Similarity searching with FTrees-FS allows the systematic exploration of this space without the need to enumerate all product structures. The search result is a set of virtual hits which are synthetically accessible by one or more of the existing reaction protocols. Grouping these virtual hits by their synthetic protocols allows the rapid design and synthesis of multiple follow-up libraries. Such library ideas support hit-to-lead design efforts for tasks like follow-up from high-throughput screening hits or scaffold hopping from one hit to another attractive series.

Sensor Access to the Cellular Microenvironment Using the Sensing Cell Culture Flask.

PubMed

Kieninger, Jochen; Tamari, Yaara; Enderle, Barbara; Jobst, Gerhard; Sandvik, Joe A; Pettersen, Erik O; Urban, Gerald A

2018-04-26

The Sensing Cell Culture Flask (SCCF) is a cell culture monitoring system accessing the cellular microenvironment in 2D cell culture using electrochemical microsensors. The system is based on microfabricated sensor chips embedded in standard cell culture flasks. Ideally, the sensor chips could be equipped with any electrochemical sensor. Its transparency allows optical inspection of the cells during measurement. The surface of the sensor chip is in-plane with the flask surface allowing undisturbed cell growth on the sensor chip. A custom developed rack system allows easy usage of multiple flasks in parallel within an incubator. The presented data demonstrates the application of the SCCF with brain tumor (T98G) and breast cancer (T-47D) cells. Amperometric oxygen sensors were used to monitor cellular respiration with different incubation conditions. Cellular acidification was accessed with potentiometric pH sensors using electrodeposited iridium oxide films. The system itself provides the foundation for electrochemical monitoring systems in 3D cell culture.

Pathview Web: user friendly pathway visualization and data integration

PubMed Central

Pant, Gaurav; Bhavnasi, Yeshvant K.; Blanchard, Steven G.; Brouwer, Cory

2017-01-01

Abstract Pathway analysis is widely used in omics studies. Pathway-based data integration and visualization is a critical component of the analysis. To address this need, we recently developed a novel R package called Pathview. Pathview maps, integrates and renders a large variety of biological data onto molecular pathway graphs. Here we developed the Pathview Web server, as to make pathway visualization and data integration accessible to all scientists, including those without the special computing skills or resources. Pathview Web features an intuitive graphical web interface and a user centered design. The server not only expands the core functions of Pathview, but also provides many useful features not available in the offline R package. Importantly, the server presents a comprehensive workflow for both regular and integrated pathway analysis of multiple omics data. In addition, the server also provides a RESTful API for programmatic access and conveniently integration in third-party software or workflows. Pathview Web is openly and freely accessible at https://pathview.uncc.edu/. PMID:28482075

Which way in? The Necessity of Multiple Approaches to Transcatheter Valve Therapy

PubMed Central

Bleiziffer, S.; Krane, M.; Deutsch, M.A.; Elhmidi, Y.; Piazza, N.; Voss, B.; Lange, R.

2013-01-01

TAVI (transcatheter aortic valve implantation) is a less invasive treatment of the stenotic aortic valve while avoiding midline sternotomy and cardiopulmonary bypass. A crimped biological valve on a self-expanding or balloon-expandable stent is inserted antegradely or retrogradely under fluoroscopy, and deployed on the beating heart. Among the worldwide TAVI programs, many different concepts have been established for the choice of the access site. Whether retrograde or antegrade TAVI should be considered the superior approach is matter of an ongoing debate. The published literature demonstrates safety of all techniques if performed within a dedicated multidisciplinary team. Since there is no data providing evidence if one approach is superior to another, we conclude that an individualized patient-centered decision making process is most beneficial, taking advantage of the complementarity of the different access options. The aim of this article is to give an overview of the current practice of access techniques for transcatheter based valve treatment and to outline the respective special characteristics. PMID:24313647

JASPAR 2014: an extensively expanded and updated open-access database of transcription factor binding profiles

PubMed Central

Mathelier, Anthony; Zhao, Xiaobei; Zhang, Allen W.; Parcy, François; Worsley-Hunt, Rebecca; Arenillas, David J.; Buchman, Sorana; Chen, Chih-yu; Chou, Alice; Ienasescu, Hans; Lim, Jonathan; Shyr, Casper; Tan, Ge; Zhou, Michelle; Lenhard, Boris; Sandelin, Albin; Wasserman, Wyeth W.

2014-01-01

JASPAR (http://jaspar.genereg.net) is the largest open-access database of matrix-based nucleotide profiles describing the binding preference of transcription factors from multiple species. The fifth major release greatly expands the heart of JASPAR—the JASPAR CORE subcollection, which contains curated, non-redundant profiles—with 135 new curated profiles (74 in vertebrates, 8 in Drosophila melanogaster, 10 in Caenorhabditis elegans and 43 in Arabidopsis thaliana; a 30% increase in total) and 43 older updated profiles (36 in vertebrates, 3 in D. melanogaster and 4 in A. thaliana; a 9% update in total). The new and updated profiles are mainly derived from published chromatin immunoprecipitation-seq experimental datasets. In addition, the web interface has been enhanced with advanced capabilities in browsing, searching and subsetting. Finally, the new JASPAR release is accompanied by a new BioPython package, a new R tool package and a new R/Bioconductor data package to facilitate access for both manual and automated methods. PMID:24194598

JASPAR 2014: an extensively expanded and updated open-access database of transcription factor binding profiles.

PubMed

Mathelier, Anthony; Zhao, Xiaobei; Zhang, Allen W; Parcy, François; Worsley-Hunt, Rebecca; Arenillas, David J; Buchman, Sorana; Chen, Chih-yu; Chou, Alice; Ienasescu, Hans; Lim, Jonathan; Shyr, Casper; Tan, Ge; Zhou, Michelle; Lenhard, Boris; Sandelin, Albin; Wasserman, Wyeth W

2014-01-01

JASPAR (http://jaspar.genereg.net) is the largest open-access database of matrix-based nucleotide profiles describing the binding preference of transcription factors from multiple species. The fifth major release greatly expands the heart of JASPAR-the JASPAR CORE subcollection, which contains curated, non-redundant profiles-with 135 new curated profiles (74 in vertebrates, 8 in Drosophila melanogaster, 10 in Caenorhabditis elegans and 43 in Arabidopsis thaliana; a 30% increase in total) and 43 older updated profiles (36 in vertebrates, 3 in D. melanogaster and 4 in A. thaliana; a 9% update in total). The new and updated profiles are mainly derived from published chromatin immunoprecipitation-seq experimental datasets. In addition, the web interface has been enhanced with advanced capabilities in browsing, searching and subsetting. Finally, the new JASPAR release is accompanied by a new BioPython package, a new R tool package and a new R/Bioconductor data package to facilitate access for both manual and automated methods.