BLAST for Behind-the-Meter Applications Lite Tool | Transportation Research
provided by NREL's PV Watts calculator. A generic utility rate structure framework makes it possible to the BLAST documentation for proper CSV formatting. Rate structure values Define demand charges and energy costs to best represent your utility rate structure of interest. Demand charges and energy costs
Bojórquez, Edén; Reyes-Salazar, Alfredo; Ruiz, Sonia E; Terán-Gilmore, Amador
2014-01-01
Several studies have been devoted to calibrate damage indices for steel and reinforced concrete members with the purpose of overcoming some of the shortcomings of the parameters currently used during seismic design. Nevertheless, there is a challenge to study and calibrate the use of such indices for the practical structural evaluation of complex structures. In this paper, an energy-based damage model for multidegree-of-freedom (MDOF) steel framed structures that accounts explicitly for the effects of cumulative plastic deformation demands is used to estimate the cyclic drift capacity of steel structures. To achieve this, seismic hazard curves are used to discuss the limitations of the maximum interstory drift demand as a performance parameter to achieve adequate damage control. Then the concept of cyclic drift capacity, which incorporates information of the influence of cumulative plastic deformation demands, is introduced as an alternative for future applications of seismic design of structures subjected to long duration ground motions.
Bojórquez, Edén; Reyes-Salazar, Alfredo; Ruiz, Sonia E.; Terán-Gilmore, Amador
2014-01-01
Several studies have been devoted to calibrate damage indices for steel and reinforced concrete members with the purpose of overcoming some of the shortcomings of the parameters currently used during seismic design. Nevertheless, there is a challenge to study and calibrate the use of such indices for the practical structural evaluation of complex structures. In this paper, an energy-based damage model for multidegree-of-freedom (MDOF) steel framed structures that accounts explicitly for the effects of cumulative plastic deformation demands is used to estimate the cyclic drift capacity of steel structures. To achieve this, seismic hazard curves are used to discuss the limitations of the maximum interstory drift demand as a performance parameter to achieve adequate damage control. Then the concept of cyclic drift capacity, which incorporates information of the influence of cumulative plastic deformation demands, is introduced as an alternative for future applications of seismic design of structures subjected to long duration ground motions. PMID:25089288
Restructuring the rotor analysis program C-60
NASA Technical Reports Server (NTRS)
1985-01-01
The continuing evolution of the rotary wing industry demands increasing analytical capabilities. To keep up with this demand, software must be structured to accommodate change. The approach discussed for meeting this demand is to restructure an existing analysis. The motivational factors, basic principles, application techniques, and practical lessons from experience with this restructuring effort are reviewed.
NASA Astrophysics Data System (ADS)
Ebersbach, K. F.; Fischer, A.; Layer, G.; Steinberger, W.; Wegner, M.; Wiesner, B.
1982-07-01
The energy demand in the sector of trade and commerce was registered and analyzed. Measures to improve the energy demand structure are presented. In several typical firms like hotels, office buildings, locksmith's shops, motor vehicle repair shops, butcher's shops, laundries and bakeries, detailed surveys of energy consumption were done and included in a statistic evaluation. Subjects analyzed were: development of the energy supply; technology of energy application; final energy demand broken down into demand for light, power, space heating and process heat as well as the demand for cooling; daily and annual load curves of energy consumption and their dependence on various parameters; and measures to improve the structure of energy demand. Detailed measurement points out negligences in the surveyed firms and shows possibilities for likely energy savings. In addition, standard values for specific energy consumption are obtained.
NASA Astrophysics Data System (ADS)
Ebersbach, K. F.; Fischer, A.; Layer, G.; Steinberger, W.; Wegner, M.; Wiesner, B.
1982-06-01
The energy demand in trade and commerce was analyzed. Measures to improve the energy demand structure are presented. In several typical firms, like hotels, office buildings, locksmith's shops, motor vehicle repair shops, butcher's shops, laundries and bakeries, energy consumption was surveyed and statistically evaluated. Subjects analyzed are: the development of the energy supply; the technology of energy application; the final energy demand broken down into demand for light, power, space heating and process heat as well as the demand for cooling; the daily and annual load curve of energy consumption and its dependence on various parameters; and measures to improve the structure of energy demand. The detailed measurement points out negligences in the surveyed firms and shows some possibilities for likely energy savings. In addition, standard values for specific energy consumption are obtained.
Microcomputer Applications in Planning Catalog
1987-09-01
supply options they have. Input Population , point of demand (town or rural water system), per capita use, livestock demand, price of PVC pipe, ENR...assumption be made that all structures are of one construction type (ie. 2-story, 11/2- story, brick, wood frame ) Reports A 00033 A text-oriented...processors: id, location, volume of water use, water source, service area water demands, population level, emergency POC, chemical and energy consumption
Stem cell bioprinting for applications in regenerative medicine.
Tricomi, Brad J; Dias, Andrew D; Corr, David T
2016-11-01
Many regenerative medicine applications seek to harness the biologic power of stem cells in architecturally complex scaffolds or microenvironments. Traditional tissue engineering methods cannot create such intricate structures, nor can they precisely control cellular position or spatial distribution. These limitations have spurred advances in the field of bioprinting, aimed to satisfy these structural and compositional demands. Bioprinting can be defined as the programmed deposition of cells or other biologics, often with accompanying biomaterials. In this concise review, we focus on recent advances in stem cell bioprinting, including performance, utility, and applications in regenerative medicine. More specifically, this review explores the capability of bioprinting to direct stem cell fate, engineer tissue(s), and create functional vascular networks. Furthermore, the unique challenges and concerns related to bioprinting living stem cells, such as viability and maintaining multi- or pluripotency, are discussed. The regenerative capacity of stem cells, when combined with the structural/compositional control afforded by bioprinting, provides a unique and powerful tool to address the complex demands of tissue engineering and regenerative medicine applications. © 2016 New York Academy of Sciences.
ERIC Educational Resources Information Center
Koh, Elizabeth; Ponnusamy, Letchmi Devi; Tan, Liang See; Lee, Shu-Shing; Ramos, Maria Eloisa
2014-01-01
With the ever-pressing twenty-first century demands, such as the need for new knowledge generation and application, schools today are aware of the necessity to change their structures, processes and practices to be relevant. In Singapore's centralized education system, the Ministry has introduced several decentralization initiatives in the hope of…
Recent Niobium Developments for High Strength Steel Energy Applications
NASA Astrophysics Data System (ADS)
Jansto, Steven G.
Niobium-containing high strength steel materials have been developed for oil and gas pipelines, offshore platforms, nuclear plants, boilers and alternative energy applications. Recent research and the commercialization of alternative energy applications such as windtower structural supports and power transmission gear components provide enhanced performance. Through the application of these Nb-bearing steels in demanding energy-related applications, the designer and end user experience improved toughness at low temperature, excellent fatigue resistance and fracture toughness and excellent weldability. These enhancements provide structural engineers the opportunity to further improve the structural design and performance. For example, through the adoption of these Nb-containing structural materials, several design-manufacturing companies are initiating new windtower designs operating at higher energy efficiency, lower cost, and improved overall material design performance.
Advances In High Temperature (Viscoelastoplastic) Material Modeling for Thermal Structural Analysis
NASA Technical Reports Server (NTRS)
Arnold, Steven M.; Saleeb, Atef F.
2005-01-01
Typical High Temperature Applications High Temperature Applications Demand High Performance Materials: 1) Complex Thermomechanical Loading; 2) Complex Material response requires Time-Dependent/Hereditary Models: Viscoelastic/Viscoplastic; and 3) Comprehensive Characterization (Tensile, Creep, Relaxation) for a variety of material systems.
Implementation of a mezzo-level HOV carpool model for Texas. Final report, September 1986-April 1990
DOE Office of Scientific and Technical Information (OSTI.GOV)
Benson, J.D.; Mullins, J.A.; Stokes, R.W.
1989-11-01
The report presents the results of an evaluation and adaptation of three existing high-occupancy vehicle (HOV) lane carpool demand estimation models for possible use in Houston and other large Texas cities. These models use trip tables, networks and zone structures that are consistent with the regional travel demand modeling process currently in use in Texas. By implementing the HOV carpool models in a structure that is consistent with the regional travel demand modeling process, it is possible to estimate the carpool demand for an HOV facility and to evaluate the effects of the following changes in HOV lane configuration andmore » operating strategies: (1) Effects of additional and/or alternative access points; (2) Effects of extending and HOV lane; and (3) Effects of changing the definition of eligible HOV carpools. The models have produced promising results in test applications in Houston.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Casco, Mirian E.; Silvestre-Albero, Joaquín; Ramírez-Cuesta, Anibal J.
Natural methane hydrates are believed to be the largest source of hydrocarbons on Earth. These structures are formed in specific locations such as deep-sea sediments and the permafrost based on demanding conditions of high pressure and low temperature. We report that, by taking advantage of the confinement effects on nanopore space, synthetic methane hydrates grow under mild conditions (3.5 MPa and 2 degrees C), with faster kinetics (within minutes) than nature, fully reversibly and with a nominal stoichiometry that mimics nature. Furthermore, the formation of the hydrate structures in nanospace and their similarity to natural hydrates is confirmed using inelasticmore » neutron scattering experiments and synchrotron X-ray powder diffraction. Our findings may be a step towards the application of a smart synthesis of methane hydrates in energy-demanding applications (for example, transportation).« less
NASA Astrophysics Data System (ADS)
Sweeney, Mike; Redd, Lafe; Vettese, Tom; Myatt, Ray; Uchida, David; Sellers, Del
2015-09-01
High performance stabilized EO/IR surveillance and targeting systems are in demand for a wide variety of military, law enforcement, and commercial assets for land, sea, air, and space. Operating ranges, wavelengths, and angular resolution capabilities define the requirements for EO/IR optics and sensors, and line of sight stabilization. Many materials and design configurations are available for EO/IR pointing gimbals depending on trade-offs of size, weight, power (SWaP), performance, and cost. Space and high performance military aircraft applications are often driven toward expensive but exceptionally performing beryllium and aluminum beryllium components. Commercial applications often rely on aluminum and composite materials. Gimbal design considerations include achieving minimized mass and inertia simultaneous with demanding structural, thermal, optical, and scene stabilization requirements when operating in dynamic operational environments. Manufacturing considerations include precision lapping and honing of ball bearing interfaces, brazing, welding, and casting of complex aluminum and beryllium alloy structures, and molding of composite structures. Several notional and previously developed EO/IR gimbal platforms are profiled that exemplify applicable design and manufacturing technologies.
Gleadall, Andrew; Pan, Jingzhe; Ding, Lifeng; Kruft, Marc-Anton; Curcó, David
2015-11-01
Molecular dynamics (MD) simulations are widely used to analyse materials at the atomic scale. However, MD has high computational demands, which may inhibit its use for simulations of structures involving large numbers of atoms such as amorphous polymer structures. An atomic-scale finite element method (AFEM) is presented in this study with significantly lower computational demands than MD. Due to the reduced computational demands, AFEM is suitable for the analysis of Young's modulus of amorphous polymer structures. This is of particular interest when studying the degradation of bioresorbable polymers, which is the topic of an accompanying paper. AFEM is derived from the inter-atomic potential energy functions of an MD force field. The nonlinear MD functions were adapted to enable static linear analysis. Finite element formulations were derived to represent interatomic potential energy functions between two, three and four atoms. Validation of the AFEM was conducted through its application to atomic structures for crystalline and amorphous poly(lactide). Copyright © 2015 Elsevier Ltd. All rights reserved.
Comparative analysis of quantitative efficiency evaluation methods for transportation networks
He, Yuxin; Hong, Jian
2017-01-01
An effective evaluation of transportation network efficiency could offer guidance for the optimal control of urban traffic. Based on the introduction and related mathematical analysis of three quantitative evaluation methods for transportation network efficiency, this paper compares the information measured by them, including network structure, traffic demand, travel choice behavior and other factors which affect network efficiency. Accordingly, the applicability of various evaluation methods is discussed. Through analyzing different transportation network examples it is obtained that Q-H method could reflect the influence of network structure, traffic demand and user route choice behavior on transportation network efficiency well. In addition, the transportation network efficiency measured by this method and Braess’s Paradox can be explained with each other, which indicates a better evaluation of the real operation condition of transportation network. Through the analysis of the network efficiency calculated by Q-H method, it can also be drawn that a specific appropriate demand is existed to a given transportation network. Meanwhile, under the fixed demand, both the critical network structure that guarantees the stability and the basic operation of the network and a specific network structure contributing to the largest value of the transportation network efficiency can be identified. PMID:28399165
Comparative analysis of quantitative efficiency evaluation methods for transportation networks.
He, Yuxin; Qin, Jin; Hong, Jian
2017-01-01
An effective evaluation of transportation network efficiency could offer guidance for the optimal control of urban traffic. Based on the introduction and related mathematical analysis of three quantitative evaluation methods for transportation network efficiency, this paper compares the information measured by them, including network structure, traffic demand, travel choice behavior and other factors which affect network efficiency. Accordingly, the applicability of various evaluation methods is discussed. Through analyzing different transportation network examples it is obtained that Q-H method could reflect the influence of network structure, traffic demand and user route choice behavior on transportation network efficiency well. In addition, the transportation network efficiency measured by this method and Braess's Paradox can be explained with each other, which indicates a better evaluation of the real operation condition of transportation network. Through the analysis of the network efficiency calculated by Q-H method, it can also be drawn that a specific appropriate demand is existed to a given transportation network. Meanwhile, under the fixed demand, both the critical network structure that guarantees the stability and the basic operation of the network and a specific network structure contributing to the largest value of the transportation network efficiency can be identified.
Methane hydrate formation in confined nanospace can surpass nature
Casco, Mirian E.; Silvestre-Albero, Joaquín; Ramírez-Cuesta, Anibal J.; ...
2015-03-02
Natural methane hydrates are believed to be the largest source of hydrocarbons on Earth. These structures are formed in specific locations such as deep-sea sediments and the permafrost based on demanding conditions of high pressure and low temperature. We report that, by taking advantage of the confinement effects on nanopore space, synthetic methane hydrates grow under mild conditions (3.5 MPa and 2 degrees C), with faster kinetics (within minutes) than nature, fully reversibly and with a nominal stoichiometry that mimics nature. Furthermore, the formation of the hydrate structures in nanospace and their similarity to natural hydrates is confirmed using inelasticmore » neutron scattering experiments and synchrotron X-ray powder diffraction. Our findings may be a step towards the application of a smart synthesis of methane hydrates in energy-demanding applications (for example, transportation).« less
NASA Astrophysics Data System (ADS)
Klebor, Maximillian; Reichmann, Olaf; Pfeiffer, Ernst K.; Ihle, Alexander; Linke, Stefan; Tschepe, Christoph; Roddecke, Susanne; Richter, Ines; Berrill, Mark; Santiago-Prowald, Julian
2012-07-01
Materials such as aluminium, titanium and carbon fibre based composites are indispensable in space business. However, special demands on spaceborne applications require both new ideas and new concepts but also powerful novel materials. These days the trend is to substitute aluminium for CFRP basically in order to safe mass or to decrease thermal expansions. Nevertheless there are upcoming requirements that cannot be met using standard CFRP materials. In this connection innovative composites have to be introduced. In the frame of this paper three major applications for such material requests are considered, i.e.: • antennas • satellite platform structural panels • radiators. The new composites need to cope with the following challenges and demands: high operational temperature range, high stiffness, high strength, high thermal conductivity, vacuum compatibility, low mass, high in- orbit stability, compatibility with metallic parts and many more. Some of these demands have to be fulfilled in conjunction. Herein the innovative composites cover new raw materials and their combination, manufacturing process enhancement as well as new inspection and test methods. It has been observed that by using the developed CFRPs it is possible to satisfy and excel the needs. However, these materials feature a different behaviour than conventional composites which has to be taken into account during future design.
Tapered slot antenna design for vehicular GPR applications
NASA Astrophysics Data System (ADS)
Bıçak, Emrullah; Yeǧin, Korkut; Nazlı, Hakki; Daǧ, Mahmut
2014-05-01
Vehicular applications of UWB GPR demand multiple GPR sensors operating in a harsh environment. One of the key elements of in the sensor is its UWB antenna which has minimal inter-element coupling, low group delay, high directivity and less prone to environmental conditions. Tapered slot antennas (TSA's) provide good impedance match, but they need to be modified for above specifications. Parasitic slot loaded TSA with balanced feed is proposed and a multi-channel antenna array structure is formed. Structural parameters are numerically analyzed and a prototype is built. Measurements show good performance for UWB GPR applications.
On-Demand Drug Release from Gold Nanoturf for a Thermo- & Chemo-Therapeutic Esophageal Stent (TES).
Lee, Sori; Hwang, Gyoyeon; Kim, Tae Hee; Kwon, S Joon; Kim, Jong Uk; Koh, Kyongbeom; Park, Byeonghak; Hong, Haeleen; Yu, Ki Jun; Chae, Heeyeop; Jung, Youngmee; Lee, Jiyeon; Kim, Tae-Il
2018-06-07
Stimuli-responsive delivery systems for cancer therapy have been increasingly used to promote the on-demand therapeutic efficacy of anticancer drugs, and in some cases, simultaneously generate heat in response to a stimulus, resulting in hyperthermia. However, their application is still limited due to the systemic drawbacks of intravenous delivery, such as rapid clearance from the bloodstream, and the repeat injections required for sustained safe dosage, which can cause over-dosing. Here, we propose a gold (Au)-coated nanoturf structure as an implantable therapeutic interface for near-infrared (NIR)-mediated on-demand hyperthermia chemotherapy. The Au nanoturf possessed long-lasting doxorubicin (DOX) duration, which helps facilitate drug release in a sustained and prolonged manner. Moreover, the Au-coated nanoturf provides reproducible hyperthermia induced by localized surface plasmon resonances (LSPRs) under NIR irradiation. Simultaneously, the NIR-mediated temperature increase can promote on-demand drug release at desired time points. For in vivo analysis, the Au nanoturf structure was applied on an esophageal stent, which needs sustained anticancer treatment to prevent tumor recurrence on the implanted surface. This thermo- and chemo-esophageal stent induced significant cancer cell death with released drug and hyperthermia. These phenomena were also confirmed by theoretical analysis. The proposed strategy provides a solution to achieve enhanced thermo-/chemotherapy, and has broad applications in sustained cancer treatments.
Solar heating and the electric utilities
NASA Astrophysics Data System (ADS)
Maidique, M. A.; Woo, B.
1980-05-01
The article considers the effect of widespread use of solar thermal systems on the role of electric utilities, emphasizing the foreseen short term economic problems. While the average electricity demand will be reduced, infrequent high demand peaks could occur when on nights and certain days, solar users with inadequate storage capacity are forced to depend upon conventional energy sources. Since utility costs are closely related to changes in peak demands, the modification of electricity rate structures as a load management technique is discussed. Some advantages of wide solar energy application for electric utilities are cited including the possibility of their key role in the development of solar heating.
ERIC Educational Resources Information Center
Todor, John I.
The author presents an overview of Pascual-Leone's Theory of Constructive Operators, a process-structural theory based upon Piagetian constructs which has evolved to both explain and predict the temporal unfolding of behavior. An application is made of the theory to the demands of a discrete motor task and prediction of (a) the minimal age…
Generic Business Model Types for Enterprise Mashup Intermediaries
NASA Astrophysics Data System (ADS)
Hoyer, Volker; Stanoevska-Slabeva, Katarina
The huge demand for situational and ad-hoc applications desired by the mass of business end users led to a new kind of Web applications, well-known as Enterprise Mashups. Users with no or limited programming skills are empowered to leverage in a collaborative manner existing Mashup components by combining and reusing company internal and external resources within minutes to new value added applications. Thereby, Enterprise Mashup environments interact as intermediaries to match the supply of providers and demand of consumers. By following the design science approach, we propose an interaction phase model artefact based on market transaction phases to structure required intermediary features. By means of five case studies, we demonstrate the application of the designed model and identify three generic business model types for Enterprise Mashups intermediaries (directory, broker, and marketplace). So far, intermediaries following a real marketplace business model don’t exist in context of Enterprise Mashups and require further research for this emerging paradigm.
Nonlinear Constitutive Relations for High Temperature Application, 1984
NASA Technical Reports Server (NTRS)
1985-01-01
Nonlinear constitutive relations for high temperature applications were discussed. The state of the art in nonlinear constitutive modeling of high temperature materials was reviewed and the need for future research and development efforts in this area was identified. Considerable research efforts are urgently needed in the development of nonlinear constitutive relations for high temperature applications prompted by recent advances in high temperature materials technology and new demands on material and component performance. Topics discussed include: constitutive modeling, numerical methods, material testing, and structural applications.
Preliminary study of ultrasonic structural quality control of Swiss-type cheese.
Eskelinen, J J; Alavuotunki, A P; Haeggström, E; Alatossava, T
2007-09-01
There is demand for a new nondestructive cheese-structure analysis method for Swiss-type cheese. Such a method would provide the cheese-making industry the means to enhance process control and quality assurance. This paper presents a feasibility study on ultrasonic monitoring of the structural quality of Swiss cheese by using a single-transducer 2-MHz longitudinal mode pulse-echo setup. A volumetric ultrasonic image of a cheese sample featuring gas holes (cheese-eyes) and defects (cracks) in the scan area is presented. The image is compared with an optical reference image constructed from dissection images of the same sample. The results show that the ultrasonic method is capable of monitoring the gas-solid structure of the cheese during the ripening process. Moreover, the method can be used to detect and to characterize cheese-eyes and cracks in ripened cheese. Industrial application demands were taken into account when conducting the measurements.
Probabilistic Analysis of Structural Member from Recycled Aggregate Concrete
NASA Astrophysics Data System (ADS)
Broukalová, I.; Šeps, K.
2017-09-01
The paper aims at the topic of sustainable building concerning recycling of waste rubble concrete from demolition. Considering demands of maximising recycled aggregate use and minimising of cement consumption, composite from recycled concrete aggregate was proposed. The objective of the presented investigations was to verify feasibility of the recycled aggregate cement based fibre reinforced composite in a structural member. Reliability of wall from recycled aggregate fibre reinforced composite was assessed in a probabilistic analysis of a load-bearing capacity of the wall. The applicability of recycled aggregate fibre reinforced concrete in structural applications was demonstrated. The outcomes refer to issue of high scatter of material parameters of recycled aggregate concretes.
NASA Astrophysics Data System (ADS)
Neverre, Noémie; Dumas, Patrice
2014-05-01
The aim is to be able to assess future domestic water demands in a region with heterogeneous levels of economic development. This work offers an original combination of a quantitative projection of demands (similar to WaterGAP methodology) and an estimation of the marginal benefit of water. This method is applicable to different levels of economic development and usable for large-scale hydroeconomic modelling. The global method consists in building demand functions taking into account the impact of both the price of water and the level of equipment, proxied by economic development, on domestic water demand. Our basis is a 3-blocks inverse demand function: the first block consists of essential water requirements for food and hygiene; the second block matches intermediate needs; and the last block corresponds to additional water consumption, such as outdoor uses, which are the least valued. The volume of the first block is fixed to match recommended basic water requirements from the literature, but we assume that the volume limits of blocks 2 and 3 depend on the level of household equipment and therefore evolve with the level of GDP per capita (structural change), with a saturation. For blocks 1 and 2 we determine the value of water from elasticity, price and quantity data from the literature, using the point-extension method. For block 3, we use a hypothetical zero-cost demand and maximal demand with actual water costs to linearly interpolate the inverse demand function. These functions are calibrated on the 24 countries part of the Mediterranean basin using data from SIMEDD, and are used for the projection and valuation of domestic water demands at the 2050 horizon. They enable to project total water demand, and also the respective shares of the different categories of demand (basic demand, intermediate demand and additional uses). These projections are performed under different combined scenarios of population, GDP and water costs.
STAR - A computer language for hybrid AI applications
NASA Technical Reports Server (NTRS)
Borchardt, G. C.
1986-01-01
Constructing Artificial Intelligence application systems which rely on both symbolic and non-symbolic processing places heavy demands on the communication of data between dissimilar languages. This paper describes STAR (Simple Tool for Automated Reasoning), a computer language for the development of AI application systems which supports the transfer of data structures between a symbolic level and a non-symbolic level defined in languages such as FORTRAN, C and PASCAL. The organization of STAR is presented, followed by the description of an application involving STAR in the interpretation of airborne imaging spectrometer data.
The development of Nb-based advanced intermetallic alloys for structural applications
NASA Astrophysics Data System (ADS)
Subramanian, P. R.; Mendiratta, M. G.; Dimiduk, D. M.
1996-01-01
A new generation of refractory material systems with significant increases in temperature capability is required to meet the demands of future aerospace applications. Such materials require a balance of properties such as low-temperature damage tolerance, high-temperature strength, creep resistance, and superior environmental stability for implementation in advanced aerospace systems. Systems incorporating niobium-based beta alloys and intermetallic compounds have the potential for meeting these requirements.
High-rate RTK and PPP multi-GNSS positioning for small-scale dynamic displacements monitoring
NASA Astrophysics Data System (ADS)
Paziewski, Jacek; Sieradzki, Rafał; Baryła, Radosław; Wielgosz, Pawel
2017-04-01
The monitoring of dynamic displacements and deformations of engineering structures such as buildings, towers and bridges is of great interest due to several practical and theoretical reasons. The most important is to provide information required for safe maintenance of the constructions. High temporal resolution and precision of GNSS observations predestine this technology to be applied to most demanding application in terms of accuracy, availability and reliability. GNSS technique supported by appropriate processing methodology may meet the specific demands and requirements of ground and structures monitoring. Thus, high-rate multi-GNSS signals may be used as reliable source of information on dynamic displacements of ground and engineering structures, also in real time applications. In this study we present initial results of application of precise relative GNSS positioning for detection of small scale (cm level) high temporal resolution dynamic displacements. Methodology and algorithms applied in self-developed software allowing for relative positioning using high-rate dual-frequency phase and pseudorange GPS+Galileo observations are also given. Additionally, an approach was also made to use the Precise Point Positioning technique to such application. In the experiment were used the observations obtained from high-rate (20 Hz) geodetic receivers. The dynamic displacements were simulated using specially constructed device moving GNSS antenna with dedicated amplitude and frequency. The obtained results indicate on possibility of detection of dynamic displacements of the GNSS antenna even at the level of few millimetres using both relative and Precise Point Positioning techniques after suitable signals processing.
NASA Astrophysics Data System (ADS)
Tornari, Vivi; Andrianakis, Michalis; Hatzigiannakis, Kostas; Kosma, Kiki; Detalle, Vincent; Giovanacci, David
2017-07-01
The demand for non destructive and non invasive structural diagnostic techniques able to perform on field remote structural evaluation of historical structures and works of art it faces an increased demand. The techniques must have some basic important characteristics The non destructivity, accuracy, repeatability, non physical contact, portability, resolution, broad range of applicability depending on the type of artwork and the question at hand, are all among the important requirements underlying the requirement for on-field structural diagnostics. In this respect there are two known techniques that have been developed at full to provide a suited structural diagnostic application in artwork conservation. The systems presented here but discussed in detail elsewhere are stimulated infrared thermography (SIRT) and digital holographic speckle pattern interferometry (DHSPI) the prior can be found n market at commercial devise level while the latter is at laboratory prototype level. The two systems are being exploited for their complimentary advantages and in this paper are used in combined testing on art related targets according to the above criteria to confirm the enhanced diagnostic information that their complimentary use provides. Results confirm the effectiveness of each technique alone and the combination of data of both techniques in the conservation field. Each system is first briefly described and examples are given with the aim to present the suitability and appropriateness for use in structural documentation analysis and reports. The experimental work is in laboratory work-in-progress focusing on the hybriding of data synthesis.
Protein Bricks: 2D and 3D Bio-Nanostructures with Shape and Function on Demand.
Jiang, Jianjuan; Zhang, Shaoqing; Qian, Zhigang; Qin, Nan; Song, Wenwen; Sun, Long; Zhou, Zhitao; Shi, Zhifeng; Chen, Liang; Li, Xinxin; Mao, Ying; Kaplan, David L; Gilbert Corder, Stephanie N; Chen, Xinzhong; Liu, Mengkun; Omenetto, Fiorenzo G; Xia, Xiaoxia; Tao, Tiger H
2018-05-01
Precise patterning of polymer-based biomaterials for functional bio-nanostructures has extensive applications including biosensing, tissue engineering, and regenerative medicine. Remarkable progress is made in both top-down (based on lithographic methods) and bottom-up (via self-assembly) approaches with natural and synthetic biopolymers. However, most methods only yield 2D and pseudo-3D structures with restricted geometries and functionalities. Here, it is reported that precise nanostructuring on genetically engineered spider silk by accurately directing ion and electron beam interactions with the protein's matrix at the nanoscale to create well-defined 2D bionanopatterns and further assemble 3D bionanoarchitectures with shape and function on demand, termed "Protein Bricks." The added control over protein sequence and molecular weight of recombinant spider silk via genetic engineering provides unprecedented lithographic resolution (approaching the molecular limit), sharpness, and biological functions compared to natural proteins. This approach provides a facile method for patterning and immobilizing functional molecules within nanoscopic, hierarchical protein structures, which sheds light on a wide range of biomedical applications such as structure-enhanced fluorescence and biomimetic microenvironments for controlling cell fate. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Aluminum automotive space frames
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1995-08-01
Design of aluminum structures is to a new topic. Aircraft makers have successfully solved difficult structural problems with a high degree of understanding and reliability. Other transportation modes such as trucks, trailers, and railcars have faced structural problems with some emphasis on high- and low-cycle fatigue of welded aluminum structures. However, the automotive market places stringent engineering demands on materials and superimposes demanding cost constraints. A project was instituted at Reynolds Metals Co. to investigate the opportunities for the cost-effective application of aluminum to automotive spaceframes. Several areas were recognized as key to the success of this application. They were:more » equivalent or superior structural stiffness of the assembly to existing steel unibody and/or steel spaceframe vehicles; effective joining of spaceframe members; equivalent or superior crashworthiness of the assembly; weight savings; flexibility; and low-cost approach aimed at effective manufacturing. To gain experience with the key aspects in a practical environment, the experience of current builders of steel tube frame chassis was explored. These chassis are typically used in low-volume vehicles requiring torsional stiffness, excellent crashworthiness, and exterior body-style flexibility. A model was developed using finite element methods that accurately predicts mass and stiffness of frames. An effective aluminum space frame was generated which was 7.5% stiffer and more than 20% lighter than the steel frame, with stresses kept below the fatigue limit for aluminum welds.« less
High-Temperature Resistance Strain Gauges
NASA Technical Reports Server (NTRS)
Lei, Jih-Fen
1994-01-01
Resistance strain gauges developed for use at high temperatures in demanding applications like testing aircraft engines and structures. Measures static strains at temperatures up to 800 degrees C. Small and highly reproducible. Readings corrected for temperature within small tolerances, provided temperatures measured simultaneously by thermocouples or other suitable devices. Connected in wheatstone bridge.
ERIC Educational Resources Information Center
Garn, Alex C.
2017-01-01
Multidimensional measurement is a common theme in motivation research because many constructs are conceptualized as having an overarching general factor (e.g., situational interest) and specific dimensions (e.g., attention demand, challenge, exploration intention, instant enjoyment, novelty). This review addresses current issues associated with…
Forecasting Pell Program Applications Using Structural Aggregate Models.
ERIC Educational Resources Information Center
Cavin, Edward S.
1995-01-01
Demand for Pell Grant financial aid has become difficult to predict when using the current microsimulation model. This paper proposes an alternative model that uses aggregate data (based on individuals' microlevel decisions and macrodata on family incomes, college costs, and opportunity wages) and avoids some limitations of simple linear models.…
PACS—Realization of an adaptive concept using pressure actuated cellular structures
NASA Astrophysics Data System (ADS)
Gramüller, B.; Boblenz, J.; Hühne, C.
2014-10-01
A biologically inspired concept is investigated which can be utilized to develop energy efficient, lightweight and applicational flexible adaptive structures. Building a real life morphing unit is an ambitious task as the numerous works in the particular field show. Summarizing fundamental demands and barriers regarding shape changing structures, the basic challenges of designing morphing structures are listed. The concept of Pressure Actuated Cellular Structures (PACS) is arranged within the recent morphing activities and it is shown that it complies with the underlying demands. Systematically divided into energy-related and structural subcomponents the working principle is illuminated and relationships between basic design parameters are expressed. The analytical background describing the physical mechanisms of PACS is presented in concentrated manner. This work focuses on the procedure of dimensioning, realizing and experimental testing of a single cell and a single row cantilever made of PACS. The experimental outcomes as well as the results from the FEM computations are used for evaluating the analytical methods. The functionality of the basic principle is thus validated and open issues are determined pointing the way ahead.
Niobium Application, Metallurgy and Global Trends in Pressure Vessel Steels
NASA Astrophysics Data System (ADS)
Jansto, Steven G.
Niobium-containing high strength steel materials have been developed for a variety of pressure vessel applications. Through the application of these Nb-bearing steels in demanding applications, the designer and end user experience improved toughness at low temperature, excellent fatigue resistance and fracture toughness and excellent weldability. These enhancements provide structural engineers the opportunity to further improve the pressure vessel design and performance. The Nb-microalloy alloy designs also result in reduced operational production cost at the steel operation, thereby embracing the value-added attribute Nb provides to both the producer and the end user throughout the supply chain. For example, through the adoption of these Nb-containing structural materials, several design-manufacturing companies are considering improved designs which offer improved manufacturability, lower overall cost and better life cycle performance.
Pricing for scarcity? An efficiency analysis of increasing block tariffs
NASA Astrophysics Data System (ADS)
Monteiro, Henrique; Roseta-Palma, Catarina
2011-06-01
Water pricing schedules often contain significant nonlinearities, such as the increasing block tariff (IBT) structure that is abundantly applied for residential users. The IBT is frequently supported as a good tool for achieving the goals of equity, water conservation, and revenue neutrality but seldom has been grounded on efficiency justifications. In particular, existing literature on water pricing establishes that although efficient schedules will depend on demand and supply characteristics, IBT cannot usually be recommended. In this paper, we consider whether the explicit inclusion of scarcity considerations can strengthen the appeal of IBT. Results show that when both demand and costs react to climate factors, increasing marginal prices may come about as a response to a combination of water scarcity and customer heterogeneity. We derive testable conditions and then illustrate their application through an estimation of Portuguese residential water demand. We show that the recommended tariff schedule hinges crucially on the choice of functional form for demand.
Examination of simplified travel demand model. [Internal volume forecasting model
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smith, R.L. Jr.; McFarlane, W.J.
1978-01-01
A simplified travel demand model, the Internal Volume Forecasting (IVF) model, proposed by Low in 1972 is evaluated as an alternative to the conventional urban travel demand modeling process. The calibration of the IVF model for a county-level study area in Central Wisconsin results in what appears to be a reasonable model; however, analysis of the structure of the model reveals two primary mis-specifications. Correction of the mis-specifications leads to a simplified gravity model version of the conventional urban travel demand models. Application of the original IVF model to ''forecast'' 1960 traffic volumes based on the model calibrated for 1970more » produces accurate estimates. Shortcut and ad hoc models may appear to provide reasonable results in both the base and horizon years; however, as shown by the IVF mode, such models will not always provide a reliable basis for transportation planning and investment decisions.« less
Engineering aspects of the application of structural materials in the 5 MW-ESS-mercury-target
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guttek, B.
1996-06-01
A main problem of the ESS-Hg-target development and the design of the components of its primary Hg-circuit is the choice of structural materials. As designing, calculations and experiments with elected materials take time and are very costy, a preview on their successful application has to be done before as detailed as possible. One aspect on this is to have the knowledge of characteristics values of the structural material candidates under the occuring mechanical and thermal loads, irradiation, corrosion and erosion. Another point is the technology of engineering concerning the manufacturing, welding, surface treatment, and quality control of such parts andmore » components under the demand to reach maximum lifetime.« less
ERIC Educational Resources Information Center
Piele, Philip K.
This document shows how computer technology can aid educators in meeting demands for improved class scheduling and more efficient use of transportation resources. The first section surveys literature on operational systems that provide individualized scheduling for students, varied class structures, and maximum use of space and staff skills.…
Shock spectra applications to a class of multiple degree-of-freedom structures system
NASA Technical Reports Server (NTRS)
Hwang, Shoi Y.
1988-01-01
The demand on safety performance of launching structure and equipment system from impulsive excitations necessitates a study which predicts the maximum response of the system as well as the maximum stresses in the system. A method to extract higher modes and frequencies for a class of multiple degree-of-freedom (MDOF) Structure system is proposed. And, along with the shock spectra derived from a linear oscillator model, a procedure to obtain upper bound solutions for maximum displacement and maximum stresses in the MDOF system is presented.
NASA Astrophysics Data System (ADS)
Hübler, M.; Nissle, S.; Gurka, M.; Wassenaar, J.
2016-04-01
Static vortex generators (VGs) are installed on different aircraft types. They generate vortices and interfuse the slow boundary layer with the fast moving air above. Due to this energizing, a flow separation of the boundary layer can be suppressed at high angles of attack. However the VGs cause a permanently increased drag over the whole flight cycle reducing the cruise efficiency. This drawback is currently limiting the use of VGs. New active VGs, deployed only on demand at low speed, can help to overcome this contradiction. Active hybrid structures, combining the actuation of shape memory alloys (SMA) with fiber reinforced polymers (FRP) on the materials level, provide an actuation principle with high lightweight potential and minimum space requirements. Being one of the first applications of active hybrid structures from SMA and FRP, these active vortex generators help to demonstrate the advantages of this new technology. A new design approach and experimental results of active VGs are presented based on the application of unique design tools and advanced manufacturing approaches for these active hybrid structures. The experimental investigation of the actuation focuses on the deflection potential and the dynamic response. Benchmark performance data such as a weight of 1.5g and a maximum thickness of only 1.8mm per vortex generator finally ensure a simple integration in the wing structure.
Sargianis, James; Kim, Hyung-ick; Suhr, Jonghwan
2012-01-01
Carbon fiber-synthetic foam core sandwich composites are widely used for many structural applications due to their superior mechanical performance and low weight. Unfortunately these structures typically have very poor acoustic performance. There is increasingly growing demand in mitigating this noise issue in sandwich composite structures. This study shows that marrying carbon fiber composites with natural cork in a sandwich structure provides a synergistic effect yielding a noise-free sandwich composite structure without the sacrifice of mechanical performance or weight. Moreover the cork-core sandwich composites boast a 250% improvement in damping performance, providing increased durability and lifetime operation. Additionally as the world seeks environmentally friendly materials, the harvesting of cork is a natural, renewable process which reduces subsequent carbon footprints. Such a transition from synthetic foam cores to natural cork cores could provide unprecedented improvements in acoustic and vibrational performance in applications such as aircraft cabins or wind turbine blades.
Ultra-High Gradient S-band Linac for Laboratory and Industrial Applications
NASA Astrophysics Data System (ADS)
Faillace, L.; Agustsson, R.; Dolgashev, V.; Frigola, P.; Murokh, A.; Rosenzweig, J.; Yakimenko, V.
2010-11-01
A strong demand for high gradient structures arises from the limited real estate available for linear accelerators. RadiaBeam Technologies is developing a Doubled Energy Compact Accelerator (DECA) structure: an S-band standing wave electron linac designed to operate at accelerating gradients of up to 50 MV/m. In this paper, we present the radio-frequency design of the DECA S-band accelerating structure, operating at 2.856 GHz in the π-mode. The structure design is heavily influenced by NLC collaboration experience with ultra high gradient X-band structures; S-band, however, is chosen to take advantage of commonly available high power S-band klystrons.
New generation of the health monitoring system SMS 2001
NASA Astrophysics Data System (ADS)
Berndt, Rolf-Dietrich; Schwesinger, Peter
2001-08-01
The Structure Monitoring System SMS 2001 (applied for patent) represents a modular structured multi-component measurement devise for use under outdoor conditions. Besides usual continuously (static) measurements of e.g. environmental parameters and structure related responses the SMS is able to register also short term dynamic events automatically with measurement frequencies up to 1 kHz. A larger range of electrical sensors is able to be used. On demand a solar based power supply can be realized. The SMS 2001 is adaptable in a wide range, it is space-saving in its geometric structure and can meet very various demands of the users. The system is applicable preferably for small and medium sized concrete and steel structures (besides buildings and bridges also for special cases). It is suitable to support the efficient concept of a controlled life time extension especially in the case of pre-damaged structures. The interactive communication between SMS and the central office is completely remote controlled. Two point or multi-point connections using the internet can be realized. The measurement data are stored in a central data bank. A safe access supported by software modules can be organized in different levels, e.g. for scientific evaluation, service reasons or needs of authorities.
Design Considerations for an Integrated Solar Sail Diagnostics System
NASA Technical Reports Server (NTRS)
Jenkins, Christopher H. M.; Gough, Aaron R.; Pappa, Richard S.; Carroll, Joe; Blandino, Joseph R.; Miles, Jonathan J.; Rakoczy, John
2004-01-01
Efforts are continuing under NASA support to improve the readiness level of solar sail technology. Solar sails have one of the best chances to be the next gossamer spacecraft flown in space. In the gossamer spacecraft community thus far, solar sails have always been considered a "low precision" application compared with, say, radar or optical devices. However, as this paper shows, even low precision gossamer applications put extraordinary demands on structural measurement systems if they are to be traceable to use in space.
NASA Astrophysics Data System (ADS)
Blokker, Mirjam; Agudelo-Vera, Claudia; Moerman, Andreas; van Thienen, Peter; Pieterse-Quirijns, Ilse
2017-04-01
Many researchers have developed drinking water demand models with various temporal and spatial scales. A limited number of models is available at a temporal scale of 1 s and a spatial scale of a single home. The reasons for building these models were described in the papers in which the models were introduced, along with a discussion on their potential applications. However, the predicted applications are seldom re-examined. SIMDEUM, a stochastic end-use model for drinking water demand, has often been applied in research and practice since it was developed. We are therefore re-examining its applications in this paper. SIMDEUM's original purpose was to calculate maximum demands in order to design self-cleaning networks. Yet, the model has been useful in many more applications. This paper gives an overview of the many fields of application for SIMDEUM and shows where this type of demand model is indispensable and where it has limited practical value. This overview also leads to an understanding of the requirements for demand models in various applications.
Growing kidney tissue from stem cells: how far from ‘party trick’ to medical application?
Little, Melissa H
2016-01-01
The successful generation of kidney-like structures from human pluripotent stem cells, although slower to come than other tissue types, brings the hope of new therapies. While the demand for alternative treatments for kidney failure is acute, huge challenges remain to move these exciting but preliminary results towards clinical use. PMID:27257757
ERIC Educational Resources Information Center
Cai, Yuzhuo; Yang, Po; Lyytinen, Anu; Hölttä, Seppo
2015-01-01
China has recently launched a radical reform to transform over 600 regional universities into application and technology oriented institutions. The reform is a response to diverse labour market demands, regional economic development and the suboptimal structure of the higher education system, and uses international experiences as a reference.…
The structure optimization of gas-phase surface discharge and its application for dye degradation
NASA Astrophysics Data System (ADS)
Ying, CAO; Jie, LI; Nan, JIANG; Yan, WU; Kefeng, SHANG; Na, LU
2018-05-01
A gas-phase surface discharge (GSD) was employed to optimize the discharge reactor structure and investigate the dye degradation. A dye mixture of methylene blue, acid orange and methyl orange was used as a model pollutant. The results indicated that the reactor structure of the GSD system with the ratio of tube inner surface area and volume of 2.48, screw pitch between a high-voltage electrode of 9.7 mm, high-voltage electrode wire diameter of 0.8 mm, dielectric tube thickness of 2.0 mm and tube inner diameter of 16.13 mm presented a better ozone (O3) generation efficiency. Furthermore, a larger screw pitch and smaller wire diameter enhanced the O3 generation. After the dye mixture degradation by the optimized GSD system, 73.21% and 50.74% of the chemical oxygen demand (COD) and total organic carbon removal rate were achieved within 20 min, respectively, and the biochemical oxygen demand (BOD) and biodegradability (BOD/COD) improved.
Earthquake behavior of steel cushion-implemented reinforced concrete frames
NASA Astrophysics Data System (ADS)
Özkaynak, Hasan
2018-04-01
The earthquake performance of vulnerable structures can be increased by the implementation of supplementary energy-dissipative metallic elements. The main aim of this paper is to describe the earthquake behavior of steel cushion-implemented reinforced concrete frames (SCI-RCFR) in terms of displacement demands and energy components. Several quasi-static experiments were performed on steel cushions (SC) installed in reinforced concrete (RC) frames. The test results served as the basis of the analytical models of SCs and a bare reinforced concrete frame (B-RCFR). These models were integrated in order to obtain the resulting analytical model of the SCI-RCFR. Nonlinear-time history analyses (NTHA) were performed on the SCI-RCFR under the effects of the selected earthquake data set. According to the NTHA, SC application is an effective technique for increasing the seismic performance of RC structures. The main portion of the earthquake input energy was dissipated through SCs. SCs succeeded in decreasing the plastic energy demand on structural elements by almost 50% at distinct drift levels.
Kračun, Stjepan Krešimir; Fangel, Jonatan Ulrik; Rydahl, Maja Gro; Pedersen, Henriette Lodberg; Vidal-Melgosa, Silvia; Willats, William George Tycho
2017-01-01
Cell walls are an important feature of plant cells and a major component of the plant glycome. They have both structural and physiological functions and are critical for plant growth and development. The diversity and complexity of these structures demand advanced high-throughput techniques to answer questions about their structure, functions and roles in both fundamental and applied scientific fields. Microarray technology provides both the high-throughput and the feasibility aspects required to meet that demand. In this chapter, some of the most recent microarray-based techniques relating to plant cell walls are described together with an overview of related contemporary techniques applied to carbohydrate microarrays and their general potential in glycoscience. A detailed experimental procedure for high-throughput mapping of plant cell wall glycans using the comprehensive microarray polymer profiling (CoMPP) technique is included in the chapter and provides a good example of both the robust and high-throughput nature of microarrays as well as their applicability to plant glycomics.
NASA Astrophysics Data System (ADS)
Abdel Raheem, Shehata E.; Ahmed, Mohamed M.; Alazrak, Tarek M. A.
2015-03-01
Soil conditions have a great deal to do with damage to structures during earthquakes. Hence the investigation on the energy transfer mechanism from soils to buildings during earthquakes is critical for the seismic design of multi-story buildings and for upgrading existing structures. Thus, the need for research into soil-structure interaction (SSI) problems is greater than ever. Moreover, recent studies show that the effects of SSI may be detrimental to the seismic response of structure and neglecting SSI in analysis may lead to un-conservative design. Despite this, the conventional design procedure usually involves assumption of fixity at the base of foundation neglecting the flexibility of the foundation, the compressibility of the underneath soil and, consequently, the effect of foundation settlement on further redistribution of bending moment and shear force demands. Hence the SSI analysis of multi-story buildings is the main focus of this research; the effects of SSI are analyzed for typical multi-story building resting on raft foundation. Three methods of analysis are used for seismic demands evaluation of the target moment-resistant frame buildings: equivalent static load; response spectrum methods and nonlinear time history analysis with suit of nine time history records. Three-dimensional FE model is constructed to investigate the effects of different soil conditions and number of stories on the vibration characteristics and seismic response demands of building structures. Numerical results obtained using SSI model with different soil conditions are compared to those corresponding to fixed-base support modeling assumption. The peak responses of story shear, story moment, story displacement, story drift, moments at beam ends, as well as force of inner columns are analyzed. The results of different analysis approaches are used to evaluate the advantages, limitations, and ease of application of each approach for seismic analysis.
14 CFR 135.4 - Applicability of rules for eligible on-demand operations.
Code of Federal Regulations, 2011 CFR
2011-01-01
...-demand operations. 135.4 Section 135.4 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... OPERATIONS OPERATING REQUIREMENTS: COMMUTER AND ON DEMAND OPERATIONS AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT General § 135.4 Applicability of rules for eligible on-demand operations. (a) An...
Using directed information for influence discovery in interconnected dynamical systems
NASA Astrophysics Data System (ADS)
Rao, Arvind; Hero, Alfred O.; States, David J.; Engel, James Douglas
2008-08-01
Structure discovery in non-linear dynamical systems is an important and challenging problem that arises in various applications such as computational neuroscience, econometrics, and biological network discovery. Each of these systems have multiple interacting variables and the key problem is the inference of the underlying structure of the systems (which variables are connected to which others) based on the output observations (such as multiple time trajectories of the variables). Since such applications demand the inference of directed relationships among variables in these non-linear systems, current methods that have a linear assumption on structure or yield undirected variable dependencies are insufficient. Hence, in this work, we present a methodology for structure discovery using an information-theoretic metric called directed time information (DTI). Using both synthetic dynamical systems as well as true biological datasets (kidney development and T-cell data), we demonstrate the utility of DTI in such problems.
Optical signal processing of spatially distributed sensor data in smart structures
NASA Technical Reports Server (NTRS)
Bennett, K. D.; Claus, R. O.; Murphy, K. A.; Goette, A. M.
1989-01-01
Smart structures which contain dense two- or three-dimensional arrays of attached or embedded sensor elements inherently require signal multiplexing and processing capabilities to permit good spatial data resolution as well as the adequately short calculation times demanded by real time active feedback actuator drive circuitry. This paper reports the implementation of an in-line optical signal processor and its application in a structural sensing system which incorporates multiple discrete optical fiber sensor elements. The signal processor consists of an array of optical fiber couplers having tailored s-parameters and arranged to allow gray code amplitude scaling of sensor inputs. The use of this signal processor in systems designed to indicate the location of distributed strain and damage in composite materials, as well as to quantitatively characterize that damage, is described. Extension of similar signal processing methods to more complicated smart materials and structures applications are discussed.
NASA Astrophysics Data System (ADS)
Degenhardt, Richard
2014-06-01
Space industry demands for reduced development and operating costs. Structural weight reduction by exploitation of structural reserves in composite space and aerospace structures contributes to this aim, however, it requires accurate and experimentally validated stability analysis. Currently, the potential of composite light weight structures, which are prone to buckling, is not fully exploited as appropriate guidelines in the field of space applications do not exist. This paper deals with the state-of-the-art advances and challenges related to coupled stability analysis of composite structures which show very complex stability behaviour. Improved design guidelines for composites structures are still under development. This paper gives a short state-of-the-art and presents a proposal for a future design guideline.
Ontological simulation for educational process organisation in a higher educational institution
NASA Astrophysics Data System (ADS)
Berestneva, O. G.; Marukhina, O. V.; Bahvalov, S. V.; Fisochenko, O. N.; Berestneva, E. V.
2017-01-01
Following the new-generation standards is needed to form a task list connected with planning and organizing of an academic process, structure and content formation of degree programmes. Even when planning the structure and content of an academic process, one meets some problems concerning the necessity to assess the correlation between degree programmes and demands of educational and professional standards and to consider today’s job-market and students demands. The paper presents examples of ontological simulations for solutions of organizing educational process problems in a higher educational institution and gives descriptions of model development. The article presents two examples: ontological simulation when planning an educational process in a higher educational institution and ontological simulation for describing competences of an IT-specialist. The paper sets a conclusion about ontology application perceptiveness for formalization of educational process organization in a higher educational institution.
Ghislieri, Diego; Green, Anthony P; Pontini, Marta; Willies, Simon C; Rowles, Ian; Frank, Annika; Grogan, Gideon; Turner, Nicholas J
2013-07-24
The development of cost-effective and sustainable catalytic methods for the production of enantiomerically pure chiral amines is a key challenge facing the pharmaceutical and fine chemical industries. This challenge is highlighted by the estimate that 40-45% of drug candidates contain a chiral amine, fueling a demand for broadly applicable synthetic methods that deliver target structures in high yield and enantiomeric excess. Herein we describe the development and application of a "toolbox" of monoamine oxidase variants from Aspergillus niger (MAO-N) which display remarkable substrate scope and tolerance for sterically demanding motifs, including a new variant, which exhibits high activity and enantioselectivity toward substrates containing the aminodiphenylmethane (benzhydrylamine) template. By combining rational structure-guided engineering with high-throughput screening, it has been possible to expand the substrate scope of MAO-N to accommodate amine substrates containing bulky aryl substituents. These engineered MAO-N biocatalysts have been applied in deracemization reactions for the efficient asymmetric synthesis of the generic active pharmaceutical ingredients Solifenacin and Levocetirizine as well as the natural products (R)-coniine, (R)-eleagnine, and (R)-leptaflorine. We also report a novel MAO-N mediated asymmetric oxidative Pictet-Spengler approach to the synthesis of (R)-harmicine.
On modelling three-dimensional piezoelectric smart structures with boundary spectral element method
NASA Astrophysics Data System (ADS)
Zou, Fangxin; Aliabadi, M. H.
2017-05-01
The computational efficiency of the boundary element method in elastodynamic analysis can be significantly improved by employing high-order spectral elements for boundary discretisation. In this work, for the first time, the so-called boundary spectral element method is utilised to formulate the piezoelectric smart structures that are widely used in structural health monitoring (SHM) applications. The resultant boundary spectral element formulation has been validated by the finite element method (FEM) and physical experiments. The new formulation has demonstrated a lower demand on computational resources and a higher numerical stability than commercial FEM packages. Comparing to the conventional boundary element formulation, a significant reduction in computational expenses has been achieved. In summary, the boundary spectral element formulation presented in this paper provides a highly efficient and stable mathematical tool for the development of SHM applications.
Application of foam-extend on turbulent fluid-structure interaction
NASA Astrophysics Data System (ADS)
Rege, K.; Hjertager, B. H.
2017-12-01
Turbulent flow around flexible structures is likely to induce structural vibrations which may eventually lead to fatigue failure. In order to assess the fatigue life of these structures, it is necessary to take the action of the flow on the structure into account, but also the influence of the vibrating structure on the fluid flow. This is achieved by performing fluid-structure interaction (FSI) simulations. In this work, we have investigated the capability of a FSI toolkit for the finite volume computational fluid dynamics software foam-extend to simulate turbulence-induced vibrations of a flexible structure. A large-eddy simulation (LES) turbulence model has been implemented to a basic FSI problem of a flexible wall which is placed in a confined, turbulent flow. This problem was simulated for 2.32 seconds. This short simulation required over 200 computation hours, using 20 processor cores. Thereby, it has been shown that the simulation of FSI with LES is possible, but also computationally demanding. In order to make turbulent FSI simulations with foam-extend more applicable, more sophisticated turbulence models and/or faster FSI iteration schemes should be applied.
Puncture Self-Healing Polymers for Aerospace Applications
NASA Technical Reports Server (NTRS)
Gordon, Keith L.; Penner, Ronald K.; Bogert, Phil B.; Yost, W. T.; Siochi, Emilie J.
2011-01-01
Space exploration launch costs on the order of $10K per pound provide ample incentive to seek innovative, cost-effective ways to reduce structural mass without sacrificing safety and reliability. Damage-tolerant structural systems can provide a route to avoiding weight penalty while enhancing vehicle safety and reliability. Self-healing polymers capable of spontaneous puncture repair show great promise to mitigate potentially catastrophic damage from events such as micrometeoroid penetration. Effective self-repair requires these materials to heal instantaneously following projectile penetration while retaining structural integrity. Poly(ethylene-co-methacrylic acid) (EMMA), also known as Surlyn is an ionomer-based copolymer that undergoes puncture reversal (self-healing) following high impact puncture at high velocities. However EMMA is not a structural engineering polymer, and will not meet the demands of aerospace applications requiring self-healing engineering materials. Current efforts to identify candidate self-healing polymer materials for structural engineering systems are reported. Rheology, high speed thermography, and high speed video for self-healing semi-crystalline and amorphous polymers will be reported.
[Design of an microwave applicator using for tumor in superficial layer].
Sun, Bing; Lu, Xiaofeng; Cao, Yi
2010-05-01
A 2.45 GHz microstrip applicator using single rectangle sheet structure is presented. Based on the radiant principle of microstrip antenna, the applicator's parameter is designed and the simulating model is set and optimized in HFSS. Measured by network analyzer, the technical target of this applicator is complied with design demand. During irradiation experiment, based on 30 W power, 30 mm radiation distance and 15 min duration experiment condition, the thermal field distribution map of phantom is obtained from the far-infrared image instrument. The 3D map shows that the region of thermal field centre has small radius and deep heat penetration. The microwave energy from this applicator can reach the tumor in superficial layer without heat injuring normal tissue around it.
Laser figuring for the generation of analog micro-optics and kineform surfaces
NASA Technical Reports Server (NTRS)
Gratrix, Edward J.
1993-01-01
To date, there have been many techniques used to generate micro-optic structures in glass or other materials. Using methods common to the lithographic industry, the manufacturing technique known as 'binary optics,' has demonstrated the use of diffractive optics in a variety of micro-optic applications. It is well established that diffractive structures have limited capability when applied in a design more suited for a refractive element. For applications that demand fast, highly efficient, broadband designs, we have developed a technique which uses laser figuring to generate the refractive micro-optical surface. This paper describes the technique used to fabricate refractive micro-optics. Recent results of micro-optics in CdZnTe focal planes are shown.
A probabilistic approach to randomness in geometric configuration of scalable origami structures
NASA Astrophysics Data System (ADS)
Liu, Ke; Paulino, Glaucio; Gardoni, Paolo
2015-03-01
Origami, an ancient paper folding art, has inspired many solutions to modern engineering challenges. The demand for actual engineering applications motivates further investigation in this field. Although rooted from the historic art form, many applications of origami are based on newly designed origami patterns to match the specific requirenments of an engineering problem. The application of origami to structural design problems ranges from micro-structure of materials to large scale deployable shells. For instance, some origami-inspired designs have unique properties such as negative Poisson ratio and flat foldability. However, origami structures are typically constrained by strict mathematical geometric relationships, which in reality, can be easily violated, due to, for example, random imperfections introduced during manufacturing, or non-uniform deformations under working conditions (e.g. due to non-uniform thermal effects). Therefore, the effects of uncertainties in origami-like structures need to be studied in further detail in order to provide a practical guide for scalable origami-inspired engineering designs. Through reliability and probabilistic analysis, we investigate the effect of randomness in origami structures on their mechanical properties. Dislocations of vertices of an origami structure have different impacts on different mechanical properties, and different origami designs could have different sensitivities to imperfections. Thus we aim to provide a preliminary understanding of the structural behavior of some common scalable origami structures subject to randomness in their geometric configurations in order to help transition the technology toward practical applications of origami engineering.
AHF: Array-Based Half-Facet Data Structure for Mixed-Dimensional and Non-manifold Meshes
2013-10-13
19a. NAME OF RESPONSIBLE PERSON 19b. TELEPHONE NUMBER James Glimm V. Dyedov, N. Ray, D. Einstein , X. Jiao, T.J. Tautges 611102 c. THIS PAGE The...Ray, D. Einstein , X. Jiao, and T. Tautges mesh data structures. Examples of such new demanding applications include coupled multiphysics simulations and...be composed of a union of topologically 1-D, 2-D, 4 V. Dyedov, N. Ray, D. Einstein , X. Jiao, and T. Tautges and 3-D objects, such as a mixture of
Configurable product design considering the transition of multi-hierarchical models
NASA Astrophysics Data System (ADS)
Ren, Bin; Qiu, Lemiao; Zhang, Shuyou; Tan, Jianrong; Cheng, Jin
2013-03-01
The current research of configurable product design mainly focuses on how to convert a predefined set of components into a valid set of product structures. With the scale and complexity of configurable products increasing, the interdependencies between customer demands and product structures grow up as well. The result is that existing product structures fails to satisfy the individual customer requirements and hence product variants are needed. This paper is aimed to build a bridge between customer demands and product structures in order to make demand-driven fast response design feasible. First of all, multi-hierarchical models of configurable product design are established with customer demand model, technical requirement model and product structure model. Then, the transition of multi-hierarchical models among customer demand model, technical requirement model and product structure model is solved with fuzzy analytic hierarchy process (FAHP) and the algorithm of multi-level matching. Finally, optimal structure according to the customer demands is obtained with the calculation of Euclidean distance and similarity of some cases. In practice, the configuration design of a clamping unit of injection molding machine successfully performs an optimal search strategy for the product variants with reasonable satisfaction to individual customer demands. The proposed method can automatically generate a configuration design with better alternatives for each product structures, and shorten the time of finding the configuration of a product.
NASA Astrophysics Data System (ADS)
Cui, Gaoying; Fan, Jie; Qin, Yuchen; Wang, Dong; Chen, Guangyan
2017-05-01
In order to promote the effective use of demand response load side resources, promote the interaction between supply and demand, enhance the level of customer service and achieve the overall utilization of energy, this paper briefly explain the background significance of design demand response information platform and current situation of domestic and foreign development; Analyse the new demand of electricity demand response combined with the application of Internet and big data technology; Design demand response information platform architecture, construct demand responsive system, analyse process of demand response strategy formulate and intelligent execution implement; study application which combined with the big data, Internet and demand response technology; Finally, from information interaction architecture, control architecture and function design perspective design implementation of demand response information platform, illustrate the feasibility of the proposed platform design scheme implemented in a certain extent.
NASA Technical Reports Server (NTRS)
Hurst, Janet
2011-01-01
A brief overview is presented of the current materials and structures research geared toward propulsion applications for NASA s Subsonic Fixed Wing Project one of four projects within the Fundamental Aeronautics Program of the NASA Aeronautics Research Mission Directorate. The Subsonic Fixed Wing (SFW) Project has selected challenging goals which anticipate an increasing emphasis on aviation s impact upon the global issue of environmental responsibility. These goals are greatly reduced noise, reduced emissions and reduced fuel consumption and address 25 to 30 years of technology development. Successful implementation of these demanding goals will require development of new materials and structural approaches within gas turbine propulsion technology. The Materials and Structures discipline, within the SFW project, comprise cross-cutting technologies ranging from basic investigations to component validation in laboratory environments. Material advances are teamed with innovative designs in a multidisciplinary approach with the resulting technology advances directed to promote the goals of reduced noise and emissions along with improved performance.
Autonomous smart sensor network for full-scale structural health monitoring
NASA Astrophysics Data System (ADS)
Rice, Jennifer A.; Mechitov, Kirill A.; Spencer, B. F., Jr.; Agha, Gul A.
2010-04-01
The demands of aging infrastructure require effective methods for structural monitoring and maintenance. Wireless smart sensor networks offer the ability to enhance structural health monitoring (SHM) practices through the utilization of onboard computation to achieve distributed data management. Such an approach is scalable to the large number of sensor nodes required for high-fidelity modal analysis and damage detection. While smart sensor technology is not new, the number of full-scale SHM applications has been limited. This slow progress is due, in part, to the complex network management issues that arise when moving from a laboratory setting to a full-scale monitoring implementation. This paper presents flexible network management software that enables continuous and autonomous operation of wireless smart sensor networks for full-scale SHM applications. The software components combine sleep/wake cycling for enhanced power management with threshold detection for triggering network wide tasks, such as synchronized sensing or decentralized modal analysis, during periods of critical structural response.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tureau, Maëva S.; Kuan, Wei-Fan; Rong, Lixia
Disordered block copolymers are generally impractical in nanopatterning applications due to their inability to self-assemble into well-defined nanostructures. However, inducing order in low molecular weight disordered systems permits the design of periodic structures with smaller characteristic sizes. Here, we have induced nanoscale phase separation from disordered triblock copolymer melts to form well-ordered lamellae, hexagonally packed cylinders, and a triply periodic gyroid network structure, using a copolymer/homopolymer blending approach, which incorporates constituent homopolymers into selective block domains. This versatile blending approach allows one to precisely target multiple nanostructures from a single disordered material and can be applied to a wide varietymore » of triblock copolymer systems for nanotemplating and nanoscale separation applications requiring nanoscale feature sizes and/or high areal feature densities.« less
NASA Technical Reports Server (NTRS)
Barro, E.; Delbufalo, A.; Rossi, F.
1993-01-01
The definition of some modern high demanding space systems requires a different approach to system definition and design from that adopted for traditional missions. System functionality is strongly coupled to the operational analysis, aimed at characterizing the dynamic interactions of the flight element with its surrounding environment and its ground control segment. Unambiguous functional, operational and performance requirements are to be defined for the system, thus improving also the successive development stages. This paper proposes a Petri Nets based methodology and two related prototype applications (to ARISTOTELES orbit control and to Hermes telemetry generation) for the operational analysis of space systems through the dynamic modeling of their functions and a related computer aided environment (ISIDE) able to make the dynamic model work, thus enabling an early validation of the system functional representation, and to provide a structured system requirements data base, which is the shared knowledge base interconnecting static and dynamic applications, fully traceable with the models and interfaceable with the external world.
NASA Astrophysics Data System (ADS)
Hadjidoukas, P. E.; Angelikopoulos, P.; Papadimitriou, C.; Koumoutsakos, P.
2015-03-01
We present Π4U, an extensible framework, for non-intrusive Bayesian Uncertainty Quantification and Propagation (UQ+P) of complex and computationally demanding physical models, that can exploit massively parallel computer architectures. The framework incorporates Laplace asymptotic approximations as well as stochastic algorithms, along with distributed numerical differentiation and task-based parallelism for heterogeneous clusters. Sampling is based on the Transitional Markov Chain Monte Carlo (TMCMC) algorithm and its variants. The optimization tasks associated with the asymptotic approximations are treated via the Covariance Matrix Adaptation Evolution Strategy (CMA-ES). A modified subset simulation method is used for posterior reliability measurements of rare events. The framework accommodates scheduling of multiple physical model evaluations based on an adaptive load balancing library and shows excellent scalability. In addition to the software framework, we also provide guidelines as to the applicability and efficiency of Bayesian tools when applied to computationally demanding physical models. Theoretical and computational developments are demonstrated with applications drawn from molecular dynamics, structural dynamics and granular flow.
A Quality Function Deployment-Based Expert System for Cotton Fibre Selection
NASA Astrophysics Data System (ADS)
Chakraborty, Shankar; Prasad, Kanika
2018-01-01
The textile industries have seen resurgence in customers' demand for quality products during the preceding few years. This product range is extremely varied, with hand-spun and hand-woven products at one end of the spectrum, while products manufactured from the capital intensive sophisticated machineries at the other end. Since, cotton fibres are predominantly employed as the raw material for manufacturing these products, their proper selection is crucial for sustainable development of the textile/spinning industries. However, availability of numerous cotton fibre alternatives with various physical properties makes this selection process unwieldy and time consuming. Thus, there is need for a structured approach that can incorporate customers' demand into the selection process. This paper demonstrates the application of a structured and logical procedure of selecting the best cotton fibre type to fulfill a set of specified end product requirements through design and development of a quality function deployment (QFD)-based expert system. The QFD technique is employed here to provide due importance to the customers' spoken and unspoken needs, and subsequently calculate the priority weights of the considered cotton fibre properties. Two real time illustrative examples are presented to explicate the applicability and potentiality of the developed expert system to resolve cotton fibre selection problems.
A Quality Function Deployment-Based Expert System for Cotton Fibre Selection
NASA Astrophysics Data System (ADS)
Chakraborty, Shankar; Prasad, Kanika
2018-06-01
The textile industries have seen resurgence in customers' demand for quality products during the preceding few years. This product range is extremely varied, with hand-spun and hand-woven products at one end of the spectrum, while products manufactured from the capital intensive sophisticated machineries at the other end. Since, cotton fibres are predominantly employed as the raw material for manufacturing these products, their proper selection is crucial for sustainable development of the textile/spinning industries. However, availability of numerous cotton fibre alternatives with various physical properties makes this selection process unwieldy and time consuming. Thus, there is need for a structured approach that can incorporate customers' demand into the selection process. This paper demonstrates the application of a structured and logical procedure of selecting the best cotton fibre type to fulfill a set of specified end product requirements through design and development of a quality function deployment (QFD)-based expert system. The QFD technique is employed here to provide due importance to the customers' spoken and unspoken needs, and subsequently calculate the priority weights of the considered cotton fibre properties. Two real time illustrative examples are presented to explicate the applicability and potentiality of the developed expert system to resolve cotton fibre selection problems.
Information Management Workflow and Tools Enabling Multiscale Modeling Within ICME Paradigm
NASA Technical Reports Server (NTRS)
Arnold, Steven M.; Bednarcyk, Brett A.; Austin, Nic; Terentjev, Igor; Cebon, Dave; Marsden, Will
2016-01-01
With the increased emphasis on reducing the cost and time to market of new materials, the need for analytical tools that enable the virtual design and optimization of materials throughout their processing - internal structure - property - performance envelope, along with the capturing and storing of the associated material and model information across its lifecycle, has become critical. This need is also fueled by the demands for higher efficiency in material testing; consistency, quality and traceability of data; product design; engineering analysis; as well as control of access to proprietary or sensitive information. Fortunately, material information management systems and physics-based multiscale modeling methods have kept pace with the growing user demands. Herein, recent efforts to establish workflow for and demonstrate a unique set of web application tools for linking NASA GRC's Integrated Computational Materials Engineering (ICME) Granta MI database schema and NASA GRC's Integrated multiscale Micromechanics Analysis Code (ImMAC) software toolset are presented. The goal is to enable seamless coupling between both test data and simulation data, which is captured and tracked automatically within Granta MI®, with full model pedigree information. These tools, and this type of linkage, are foundational to realizing the full potential of ICME, in which materials processing, microstructure, properties, and performance are coupled to enable application-driven design and optimization of materials and structures.
Byon, Ha Do; Harrington, Donna; Storr, Carla L; Lipscomb, Jane
2017-08-01
Workplace violence research in health care settings using the Job Demands-Resources (JD-R) framework is hindered by the lack of comprehensive examination of the factor structure of the JD-R measure when it includes patient violence. Is patient violence a component of job demands or its own factor as an occupational outcome? Exploratory factor analysis and confirmatory factor analysis were conducted using a sample of direct care workers in the home setting (n = 961). The overall 2-construct JD-R structure persisted. Patient violence was not identified as a separate factor from job demands; rather, two demand factors emerged: violence/emotional and workload/physical demands. Although the three-factor model fits the data, the two-factor model with patient violence being a component of job demands is a parsimonious and effective measurement framework.
On-Demand Microwave Generator of Shaped Single Photons
NASA Astrophysics Data System (ADS)
Forn-Díaz, P.; Warren, C. W.; Chang, C. W. S.; Vadiraj, A. M.; Wilson, C. M.
2017-11-01
We demonstrate the full functionality of a circuit that generates single microwave photons on demand, with a wave packet that can be modulated with a near-arbitrary shape. We achieve such a high tunability by coupling a superconducting qubit near the end of a semi-infinite transmission line. A dc superconducting quantum interference device shunts the line to ground and is employed to modify the spatial dependence of the electromagnetic mode structure in the transmission line. This control allows us to couple and decouple the qubit from the line, shaping its emission rate on fast time scales. Our decoupling scheme is applicable to all types of superconducting qubits and other solid-state systems and can be generalized to multiple qubits as well as to resonators.
NASA Astrophysics Data System (ADS)
Meacham, James R.; Jabbari, Faryar; Brouwer, Jacob; Mauzey, Josh L.; Samuelsen, G. Scott
Current high temperature fuel cell (HTFC) systems used for stationary power applications (in the 200-300 kW size range) have very limited dynamic load following capability or are simply base load devices. Considering the economics of existing electric utility rate structures, there is little incentive to increase HTFC ramping capability beyond 1 kWs -1 (0.4% s -1). However, in order to ease concerns about grid instabilities from utility companies and increase market adoption, HTFC systems will have to increase their ramping abilities, and will likely have to incorporate electrical energy storage (EES). Because batteries have low power densities and limited lifetimes in highly cyclic applications, ultra capacitors may be the EES medium of choice. The current analyses show that, because ultra capacitors have a very low energy storage density, their integration with HTFC systems may not be feasible unless the fuel cell has a ramp rate approaching 10 kWs -1 (4% s -1) when using a worst-case design analysis. This requirement for fast dynamic load response characteristics can be reduced to 1 kWs -1 by utilizing high resolution demand data to properly size ultra capacitor systems and through demand management techniques that reduce load volatility.
NASA Astrophysics Data System (ADS)
Zheng, Yingying
The growing energy demands and needs for reducing carbon emissions call more and more attention to the development of renewable energy technologies and management strategies. Microgrids have been developed around the world as a means to address the high penetration level of renewable generation and reduce greenhouse gas emissions while attempting to address supply-demand balancing at a more local level. This dissertation presents a model developed to optimize the design of a biomass-integrated renewable energy microgrid employing combined heat and power with energy storage. A receding horizon optimization with Monte Carlo simulation were used to evaluate optimal microgrid design and dispatch under uncertainties in the renewable energy and utility grid energy supplies, the energy demands, and the economic assumptions so as to generate a probability density function for the cost of energy. Case studies were examined for a conceptual utility grid-connected microgrid application in Davis, California. The results provide the most cost effective design based on the assumed energy load profile, local climate data, utility tariff structure, and technical and financial performance of the various components of the microgrid. Sensitivity and uncertainty analyses are carried out to illuminate the key parameters that influence the energy costs. The model application provides a means to determine major risk factors associated with alternative design integration and operating strategies.
Superalloy Lattice Block Structures
NASA Technical Reports Server (NTRS)
Nathal, M. V.; Whittenberger, J. D.; Hebsur, M. G.; Kantzos, P. T.; Krause, D. L.
2004-01-01
Initial investigations of investment cast superalloy lattice block suggest that this technology will yield a low cost approach to utilize the high temperature strength and environmental resistance of superalloys in lightweight, damage tolerant structural configurations. Work to date has demonstrated that relatively large superalloy lattice block panels can be successfully investment cast from both IN-718 and Mar-M247. These castings exhibited mechanical properties consistent with the strength of the same superalloys measured from more conventional castings. The lattice block structure also accommodates significant deformation without failure, and is defect tolerant in fatigue. The potential of lattice block structures opens new opportunities for the use of superalloys in future generations of aircraft applications that demand strength and environmental resistance at elevated temperatures along with low weight.
Nondestructive evaluation of concrete structures by nonstationary thermal wave imaging
NASA Astrophysics Data System (ADS)
Mulaveesala, Ravibabu; Panda, Soma Sekhara Balaji; Mude, Rupla Naik; Amarnath, Muniyappa
2012-06-01
Reinforced concrete structures (RCS) have potential application in civil engineering and with the advent of nuclear engineering RCS to be capable enough to withstanding a variety of adverse environmental conditions. However, failures/loss of durability of designed structures due to premature reinforcement corrosion of rebar is a major constrain. Growing concern of safety of structure due to pre-mature deterioration has led to a great demand for development of non-destructive and non-contact testing techniques for monitoring and assessing health of RCS. This paper presents an experimental investigation of rebar corrosion by non-stationary thermal wave imaging. Experimental results have been proven, proposed approach is an effective technique for identification of corrosion in rebar in the concrete samples.
Michigan's Statewide Travel Demand Model
DOT National Transportation Integrated Search
1999-09-01
The Travel Demand and Intermodal Services Section of Michigan's Department of Transportation is responsible for the development, maintenance and application of the Statewide Travel Demand Model. Michigan's Statewide and Urban Travel Demand Models are...
Post-Buckling and Ultimate Strength Analysis of Stiffened Composite Panel Base on Progressive Damage
NASA Astrophysics Data System (ADS)
Zhang, Guofan; Sun, Xiasheng; Sun, Zhonglei
Stiffened composite panel is the typical thin wall structure applied in aerospace industry, and its main failure mode is buckling subjected to compressive loading. In this paper, the development of an analysis approach using Finite Element Method on post-buckling behavior of stiffened composite structures under compression was presented. Then, the numerical results of stiffened panel are obtained by FE simulations. A thorough comparison were accomplished by comparing the load carrying capacity and key position strains of the specimen with test. The comparison indicates that the FEM results which adopted developed methodology could meet the demand of engineering application in predicting the post-buckling behavior of intact stiffened structures in aircraft design stage.
Distributed network management in the flat structured mobile communities
NASA Astrophysics Data System (ADS)
Balandina, Elena
2005-10-01
Delivering proper management into the flat structured mobile communities is crucial for improving users experience and increase applications diversity in mobile networks. The available P2P applications do application-centric management, but it cannot replace network-wide management, especially when a number of different applications are used simultaneously in the network. The network-wide management is the key element required for a smooth transition from standalone P2P applications to the self-organizing mobile communities that maintain various services with quality and security guaranties. The classical centralized network management solutions are not applicable in the flat structured mobile communities due to the decentralized nature and high mobility of the underlying networks. Also the basic network management tasks have to be revised taking into account specialties of the flat structured mobile communities. The network performance management becomes more dependent on the current nodes' context, which also requires extension of the configuration management functionality. The fault management has to take into account high mobility of the network nodes. The performance and accounting managements are mainly targeted in maintain an efficient and fair access to the resources within the community, however they also allow unbalanced resource use of the nodes that explicitly permit it, e.g. as a voluntary donation to the community or due to the profession (commercial) reasons. The security management must implement the new trust models, which are based on the community feedback, professional authorization, and a mix of both. For fulfilling these and another specialties of the flat structured mobile communities, a new network management solution is demanded. The paper presents a distributed network management solution for flat structured mobile communities. Also the paper points out possible network management roles for the different parties (e.g. operators, service providing hubs/super nodes, etc.) involved in a service providing chain.
Flexible Demand Management under Time-Varying Prices
NASA Astrophysics Data System (ADS)
Liang, Yong
In this dissertation, the problem of flexible demand management under time-varying prices is studied. This generic problem has many applications, which usually have multiple periods in which decisions on satisfying demand need to be made, and prices in these periods are time-varying. Examples of such applications include multi-period procurement problem, operating room scheduling, and user-end demand scheduling in the Smart Grid, where the last application is used as the main motivating story throughout the dissertation. The current grid is experiencing an upgrade with lots of new designs. What is of particular interest is the idea of passing time-varying prices that reflect electricity market conditions to end users as incentives for load shifting. One key component, consequently, is the demand management system at the user-end. The objective of the system is to find the optimal trade-off between cost saving and discomfort increment resulted from load shifting. In this dissertation, we approach this problem from the following aspects: (1) construct a generic model, solve for Pareto optimal solutions, and analyze the robust solution that optimizes the worst-case payoffs, (2) extend to a distribution-free model for multiple types of demand (appliances), for which an approximate dynamic programming (ADP) approach is developed, and (3) design other efficient algorithms for practical purposes of the flexible demand management system. We first construct a novel multi-objective flexible demand management model, in which there are a finite number of periods with time-varying prices, and demand arrives in each period. In each period, the decision maker chooses to either satisfy or defer outstanding demand to minimize costs and discomfort over a certain number of periods. We consider both the deterministic model, models with stochastic demand or prices, and when only partial information about the stochastic demand or prices is known. We first analyze the stochastic optimization problem when the objective is to minimize the expected total cost and discomfort, then since the decision maker is likely to be risk-averse, and she wants to protect herself from price spikes, we study the robust optimization problem to address the risk-aversion of the decision maker. We conduct numerical studies to evaluate the price of robustness. Next, we present a detailed model that manages multiple types of flexible demand in the absence of knowledge regarding the distributions of related stochastic processes. Specifically, we consider the case in which time-varying prices with general structures are offered to users, and an energy management system for each household makes optimal energy usage, storage, and trading decisions according to the preferences of users. Because of the uncertainties associated with electricity prices, local generation, and the arrival processes of demand, we formulate a stochastic dynamic programming model, and outline a novel and tractable ADP approach to overcome the curses of dimensionality. Then, we perform numerical studies, whose results demonstrate the effectiveness of the ADP approach. At last, we propose another approximation approach based on Q-learning. In addition, we also develop another decentralization-based heuristic. Both the Q-learning approach and the heuristic make necessary assumptions on the knowledge of information, and each of them has unique advantages. We conduct numerical studies on a testing problem. The simulation results show that both the Q-learning and the decentralization based heuristic approaches work well. Lastly, we conclude the paper with some discussions on future extension directions.
Complex Hollow Nanostructures: Synthesis and Energy-Related Applications.
Yu, Le; Hu, Han; Wu, Hao Bin; Lou, Xiong Wen David
2017-04-01
Hollow nanostructures offer promising potential for advanced energy storage and conversion applications. In the past decade, considerable research efforts have been devoted to the design and synthesis of hollow nanostructures with high complexity by manipulating their geometric morphology, chemical composition, and building block and interior architecture to boost their electrochemical performance, fulfilling the increasing global demand for renewable and sustainable energy sources. In this Review, we present a comprehensive overview of the synthesis and energy-related applications of complex hollow nanostructures. After a brief classification, the design and synthesis of complex hollow nanostructures are described in detail, which include hierarchical hollow spheres, hierarchical tubular structures, hollow polyhedra, and multi-shelled hollow structures, as well as their hybrids with nanocarbon materials. Thereafter, we discuss their niche applications as electrode materials for lithium-ion batteries and hybrid supercapacitors, sulfur hosts for lithium-sulfur batteries, and electrocatalysts for oxygen- and hydrogen-involving energy conversion reactions. The potential superiorities of complex hollow nanostructures for these applications are particularly highlighted. Finally, we conclude this Review with urgent challenges and further research directions of complex hollow nanostructures for energy-related applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
An object-oriented approach for parallel self adaptive mesh refinement on block structured grids
NASA Technical Reports Server (NTRS)
Lemke, Max; Witsch, Kristian; Quinlan, Daniel
1993-01-01
Self-adaptive mesh refinement dynamically matches the computational demands of a solver for partial differential equations to the activity in the application's domain. In this paper we present two C++ class libraries, P++ and AMR++, which significantly simplify the development of sophisticated adaptive mesh refinement codes on (massively) parallel distributed memory architectures. The development is based on our previous research in this area. The C++ class libraries provide abstractions to separate the issues of developing parallel adaptive mesh refinement applications into those of parallelism, abstracted by P++, and adaptive mesh refinement, abstracted by AMR++. P++ is a parallel array class library to permit efficient development of architecture independent codes for structured grid applications, and AMR++ provides support for self-adaptive mesh refinement on block-structured grids of rectangular non-overlapping blocks. Using these libraries, the application programmers' work is greatly simplified to primarily specifying the serial single grid application and obtaining the parallel and self-adaptive mesh refinement code with minimal effort. Initial results for simple singular perturbation problems solved by self-adaptive multilevel techniques (FAC, AFAC), being implemented on the basis of prototypes of the P++/AMR++ environment, are presented. Singular perturbation problems frequently arise in large applications, e.g. in the area of computational fluid dynamics. They usually have solutions with layers which require adaptive mesh refinement and fast basic solvers in order to be resolved efficiently.
Prischi, Filippo; Pastore, Annalisa
2016-01-01
The current main challenge of Structural Biology is to undertake the structure determination of increasingly complex systems in the attempt to better understand their biological function. As systems become more challenging, however, there is an increasing demand for the parallel use of more than one independent technique to allow pushing the frontiers of structure determination and, at the same time, obtaining independent structural validation. The combination of different Structural Biology methods has been named hybrid approaches. The aim of this review is to critically discuss the most recent examples and new developments that have allowed structure determination or experimentally-based modelling of various molecular complexes selecting them among those that combine the use of nuclear magnetic resonance and small angle scattering techniques. We provide a selective but focused account of some of the most exciting recent approaches and discuss their possible further developments.
Yin, Hongbiao; Huang, Shenghua; Wang, Wenlan
2016-01-01
Based on an adjusted Job Demands-Resources (JD-R) model that considers the mediation of personal resources, this study examined the relationships between two characteristics of teachers’ work environment (i.e., emotional job demands and trust in colleagues) and two indicators of teachers’ well-being (i.e., teaching satisfaction and emotional exhaustion). In particular, the study focused on how emotion regulation strategies (i.e., reappraisal and suppression) mediate these relationships. Data collected from a questionnaire survey of 1115 primary school teachers in Hong Kong was analyzed to test the hypothesized relationships. The results of structural equation modeling indicated that: (1) the emotional job demands of teaching were detrimental to teacher well-being, whereas trust in colleagues was beneficial; (2) both emotion regulation strategies mediated the relationships between both emotional job demands and trust in colleagues and teacher well-being; and (3) teachers who tend to use more reappraisal may be psychologically healthier than those tend to adopt more suppression. These findings support the applicability of the JD-R model to school settings and highlight the role of teachers’ emotion regulation in teachers’ well-being. Implications for the improvement of school environments and teachers’ well-being are identified. PMID:27649216
Yin, Hongbiao; Huang, Shenghua; Wang, Wenlan
2016-09-13
Based on an adjusted Job Demands-Resources (JD-R) model that considers the mediation of personal resources, this study examined the relationships between two characteristics of teachers' work environment (i.e., emotional job demands and trust in colleagues) and two indicators of teachers' well-being (i.e., teaching satisfaction and emotional exhaustion). In particular, the study focused on how emotion regulation strategies (i.e., reappraisal and suppression) mediate these relationships. Data collected from a questionnaire survey of 1115 primary school teachers in Hong Kong was analyzed to test the hypothesized relationships. The results of structural equation modeling indicated that: (1) the emotional job demands of teaching were detrimental to teacher well-being, whereas trust in colleagues was beneficial; (2) both emotion regulation strategies mediated the relationships between both emotional job demands and trust in colleagues and teacher well-being; and (3) teachers who tend to use more reappraisal may be psychologically healthier than those tend to adopt more suppression. These findings support the applicability of the JD-R model to school settings and highlight the role of teachers' emotion regulation in teachers' well-being. Implications for the improvement of school environments and teachers' well-being are identified.
Synthesis, functionalization, and applications of metal-organic frameworks in biomedicine.
Chen, Wei; Wu, Chunsheng
2018-02-13
Metal-organic frameworks (MOFs), also known as coordination polymers, have attracted extensive research interest in the past few decades due to their unique physical structures and potentially vast applications. In this review, we outline the recent progress in the synthesis, functionalization and applications of MOFs in biomedicine, mainly focusing on two promising, yet challenging areas, i.e., drug delivery and biosensing applications. A major challenge is the proper functionalization of MOFs with demanding properties suitable for biomedical applications. Extensive studies on MOFs in biomedicine have led to substantial progress in the control of key properties of MOFs such as toxicity, size and shape, and biological stability. Due to their flexible composition, pore size and easy functionalization properties, MOFs can be utilized as key components for the development of various functional systems, and their applications in drug delivery and biosensing are reviewed. Future trends and perspectives in these research areas are also outlined.
Direct-Write 3D Nanoprinting of Plasmonic Structures
DOE Office of Scientific and Technical Information (OSTI.GOV)
Winkler, Robert; Schmidt, Franz-Philipp; Karl-Franzens Univ.
During the past decade, significant progress has been made in the field of resonant optics ranging from fundamental aspects to concrete applications. And while several techniques have been introduced for the fabrication of highly defined metallic nanostructures, the synthesis of complex, free-standing three-dimensional (3D) structures is still an intriguing, but so far intractable, challenge. Here, we demonstrate a 3D direct-write synthesis approach that addresses this challenge. Specifically, we succeeded in the direct-write fabrication of 3D nanoarchitectures via electron-stimulated reactions, which are applicable on virtually any material and surface morphology. Furthermore, by that, complex 3D nanostructures composed of highly compact, puremore » gold can be fabricated, which reveal strong plasmonic activity and pave the way for a new generation of 3D nanoplasmonic architectures that can be printed on-demand.« less
Direct-Write 3D Nanoprinting of Plasmonic Structures
Winkler, Robert; Schmidt, Franz-Philipp; Karl-Franzens Univ.; ...
2016-11-23
During the past decade, significant progress has been made in the field of resonant optics ranging from fundamental aspects to concrete applications. And while several techniques have been introduced for the fabrication of highly defined metallic nanostructures, the synthesis of complex, free-standing three-dimensional (3D) structures is still an intriguing, but so far intractable, challenge. Here, we demonstrate a 3D direct-write synthesis approach that addresses this challenge. Specifically, we succeeded in the direct-write fabrication of 3D nanoarchitectures via electron-stimulated reactions, which are applicable on virtually any material and surface morphology. Furthermore, by that, complex 3D nanostructures composed of highly compact, puremore » gold can be fabricated, which reveal strong plasmonic activity and pave the way for a new generation of 3D nanoplasmonic architectures that can be printed on-demand.« less
Dynamic management of integrated residential energy systems
NASA Astrophysics Data System (ADS)
Muratori, Matteo
This study combines principles of energy systems engineering and statistics to develop integrated models of residential energy use in the United States, to include residential recharging of electric vehicles. These models can be used by government, policymakers, and the utility industry to provide answers and guidance regarding the future of the U.S. energy system. Currently, electric power generation must match the total demand at each instant, following seasonal patterns and instantaneous fluctuations. Thus, one of the biggest drivers of costs and capacity requirement is the electricity demand that occurs during peak periods. These peak periods require utility companies to maintain operational capacity that often is underutilized, outdated, expensive, and inefficient. In light of this, flattening the demand curve has long been recognized as an effective way of cutting the cost of producing electricity and increasing overall efficiency. The problem is exacerbated by expected widespread adoption of non-dispatchable renewable power generation. The intermittent nature of renewable resources and their non-dispatchability substantially limit the ability of electric power generation of adapting to the fluctuating demand. Smart grid technologies and demand response programs are proposed as a technical solution to make the electric power demand more flexible and able to adapt to power generation. Residential demand response programs offer different incentives and benefits to consumers in response to their flexibility in the timing of their electricity consumption. Understanding interactions between new and existing energy technologies, and policy impacts therein, is key to driving sustainable energy use and economic growth. Comprehensive and accurate models of the next-generation power system allow for understanding the effects of new energy technologies on the power system infrastructure, and can be used to guide policy, technology, and economic decisions. This dissertation presents a bottom-up highly resolved model of a generic residential energy eco-system in the United States. The model is able to capture the entire energy footprint of an individual household, to include all appliances, space conditioning systems, in-home charging of plug-in electric vehicles, and any other energy needs, viewing residential and transportation energy needs as an integrated continuum. The residential energy eco-system model is based on a novel bottom-up approach that quantifies consumer energy use behavior. The incorporation of stochastic consumer behaviors allows capturing the electricity consumption of each residential specific end-use, providing an accurate estimation of the actual amount of available controllable resources, and for a better understanding of the potential of residential demand response programs. A dynamic energy management framework is then proposed to manage electricity consumption inside each residential energy eco-system. Objective of the dynamic energy management framework is to optimize the scheduling of all the controllable appliances and in-home charging of plug-in electric vehicles to minimize cost. Such an automated energy management framework is used to simulate residential demand response programs, and evaluate their impact on the electric power infrastructure. For instance, time-varying electricity pricing might lead to synchronization of the individual residential demands, creating pronounced rebound peaks in the aggregate demand that are higher and steeper than the original demand peaks that the time-varying electricity pricing structure intended to eliminate. The modeling tools developed in this study can serve as a virtual laboratory for investigating fundamental economic and policy-related questions regarding the interplay of individual consumers with energy use. The models developed allow for evaluating the impact of different energy policies, technology adoption, and electricity price structures on the total residential electricity demand. In particular, two case studies are reported in this dissertation to illustrate application of the tools developed. The first considers the impact of market penetration of plug-in electric vehicles on the electric power infrastructure. The second provides a quantitative comparison of the impact of different electricity price structures on residential demand response. Simulation results and an electricity price structure, called Multi-TOU, aimed at solving the rebound peak issue, are presented.
Testing simulation and structural models with applications to energy demand
NASA Astrophysics Data System (ADS)
Wolff, Hendrik
2007-12-01
This dissertation deals with energy demand and consists of two parts. Part one proposes a unified econometric framework for modeling energy demand and examples illustrate the benefits of the technique by estimating the elasticity of substitution between energy and capital. Part two assesses the energy conservation policy of Daylight Saving Time and empirically tests the performance of electricity simulation. In particular, the chapter "Imposing Monotonicity and Curvature on Flexible Functional Forms" proposes an estimator for inference using structural models derived from economic theory. This is motivated by the fact that in many areas of economic analysis theory restricts the shape as well as other characteristics of functions used to represent economic constructs. Specific contributions are (a) to increase the computational speed and tractability of imposing regularity conditions, (b) to provide regularity preserving point estimates, (c) to avoid biases existent in previous applications, and (d) to illustrate the benefits of our approach via numerical simulation results. The chapter "Can We Close the Gap between the Empirical Model and Economic Theory" discusses the more fundamental question of whether the imposition of a particular theory to a dataset is justified. I propose a hypothesis test to examine whether the estimated empirical model is consistent with the assumed economic theory. Although the proposed methodology could be applied to a wide set of economic models, this is particularly relevant for estimating policy parameters that affect energy markets. This is demonstrated by estimating the Slutsky matrix and the elasticity of substitution between energy and capital, which are crucial parameters used in computable general equilibrium models analyzing energy demand and the impacts of environmental regulations. Using the Berndt and Wood dataset, I find that capital and energy are complements and that the data are significantly consistent with duality theory. Both results would not necessarily be achieved using standard econometric methods. The final chapter "Daylight Time and Energy" uses a quasi-experiment to evaluate a popular energy conservation policy: we challenge the conventional wisdom that extending Daylight Saving Time (DST) reduces energy demand. Using detailed panel data on half-hourly electricity consumption, prices, and weather conditions from four Australian states we employ a novel 'triple-difference' technique to test the electricity-saving hypothesis. We show that the extension failed to reduce electricity demand and instead increased electricity prices. We also apply the most sophisticated electricity simulation model available in the literature to the Australian data. We find that prior simulation models significantly overstate electricity savings. Our results suggest that extending DST will fail as an instrument to save energy resources.
O'Donnell, Andrew P.; Kurama, Yahya C.; Kalkan, Erol; Taflanidis, Alexandros A.
2017-01-01
This paper experimentally evaluates four methods to scale earthquake ground-motions within an ensemble of records to minimize the statistical dispersion and maximize the accuracy in the dynamic peak roof drift demand and peak inter-story drift demand estimates from response-history analyses of nonlinear building structures. The scaling methods that are investigated are based on: (1) ASCE/SEI 7–10 guidelines; (2) spectral acceleration at the fundamental (first mode) period of the structure, Sa(T1); (3) maximum incremental velocity, MIV; and (4) modal pushover analysis. A total of 720 shake-table tests of four small-scale nonlinear building frame specimens with different static and dynamic characteristics are conducted. The peak displacement demands from full suites of 36 near-fault ground-motion records as well as from smaller “unbiased” and “biased” design subsets (bins) of ground-motions are included. Out of the four scaling methods, ground-motions scaled to the median MIV of the ensemble resulted in the smallest dispersion in the peak roof and inter-story drift demands. Scaling based on MIValso provided the most accurate median demands as compared with the “benchmark” demands for structures with greater nonlinearity; however, this accuracy was reduced for structures exhibiting reduced nonlinearity. The modal pushover-based scaling (MPS) procedure was the only method to conservatively overestimate the median drift demands.
Zhang, Jiaxiang; Zallo, Eugenio; Höfer, Bianca; Chen, Yan; Keil, Robert; Zopf, Michael; Böttner, Stefan; Ding, Fei; Schmidt, Oliver G
2017-01-11
We explore a method to achieve electrical control over the energy of on-demand entangled-photon emission from self-assembled quantum dots (QDs). The device used in our work consists of an electrically tunable diode-like membrane integrated onto a piezoactuator, which is capable of exerting a uniaxial stress on QDs. We theoretically reveal that, through application of the quantum-confined Stark effect to QDs by a vertical electric field, the critical uniaxial stress used to eliminate the fine structure splitting of QDs can be linearly tuned. This feature allows experimental realization of a triggered source of energy-tunable entangled-photon emission. Our demonstration represents an important step toward realization of a solid-state quantum repeater using indistinguishable entangled photons in Bell state measurements.
Work Role Characteristics, Family Structure Demands, and Work/Family Conflict.
ERIC Educational Resources Information Center
Voydanoff, Patricia
1988-01-01
Examined relationships between work role characteristics, family structure demands, and work/family conflict, using data from 757 married men and 270 married women. Found that amount and scheduling of work time, job demands, and presence of children in home were related to work/family conflict. Work role characteristics and family structure…
The structural characteristics of inflatable beams
NASA Astrophysics Data System (ADS)
Wicker, William J.
1992-08-01
Two inflatable beams are designed and fabricated from polyethylene of ultrahigh molecular weight, and the structures are tested against similar composite and metal-alloy tubes. Specific attention is given to the choice of material that insures material stiffness, good strength-to-weight ratio, creep resistance, and durability. A cloth beam is built from a commercial extended-chain polyethylene fiber, and the inflated beams are tested by means of three- and four-point loading to measure bending and shear deformation. Comparing geometrically similar structures shows that the fabric beams can be about 35 percent as stiff as aluminum for small deflections. The inflatable beams have elastic stiffness coefficients five and two times higher than those for nylon and polyester tubes, respectively. Inflatable structures are concluded to hold promise for lightweight aerospace applications which demand small storage areas.
Thermal barrier coatings for gas-turbine engine applications.
Padture, Nitin P; Gell, Maurice; Jordan, Eric H
2002-04-12
Hundreds of different types of coatings are used to protect a variety of structural engineering materials from corrosion, wear, and erosion, and to provide lubrication and thermal insulation. Of all these, thermal barrier coatings (TBCs) have the most complex structure and must operate in the most demanding high-temperature environment of aircraft and industrial gas-turbine engines. TBCs, which comprise metal and ceramic multilayers, insulate turbine and combustor engine components from the hot gas stream, and improve the durability and energy efficiency of these engines. Improvements in TBCs will require a better understanding of the complex changes in their structure and properties that occur under operating conditions that lead to their failure. The structure, properties, and failure mechanisms of TBCs are herein reviewed, together with a discussion of current limitations and future opportunities.
NASA Technical Reports Server (NTRS)
1979-01-01
The functions performed by the systems management (SM) application software are described along with the design employed to accomplish these functions. The operational sequences (OPS) control segments and the cyclic processes they control are defined. The SM specialist function control (SPEC) segments and the display controlled 'on-demand' processes that are invoked by either an OPS or SPEC control segment as a direct result of an item entry to a display are included. Each processing element in the SM application is described including an input/output table and a structured control flow diagram. The flow through the module and other information pertinent to that process and its interfaces to other processes are included.
Light scattering techniques for the characterization of optical components
NASA Astrophysics Data System (ADS)
Hauptvogel, M.; Schröder, S.; Herffurth, T.; Trost, M.; von Finck, A.; Duparré, A.; Weigel, T.
2017-11-01
The rapid developments in optical technologies generate increasingly higher and sometimes completely new demands on the quality of materials, surfaces, components, and systems. Examples for such driving applications are the steadily shrinking feature sizes in semiconductor lithography, nanostructured functional surfaces for consumer optics, and advanced optical systems for astronomy and space applications. The reduction of surface defects as well as the minimization of roughness and other scatter-relevant irregularities are essential factors in all these areas of application. Quality-monitoring for analysing and improving those properties must ensure that even minimal defects and roughness values can be detected reliably. Light scattering methods have a high potential for a non-contact, rapid, efficient, and sensitive determination of roughness, surface structures, and defects.
High-entropy Alloys with High Saturation Magnetization, Electrical Resistivity, and Malleability
Zhang, Yong; Zuo, TingTing; Cheng, YongQiang; Liaw, Peter K.
2013-01-01
Soft magnetic materials (SMMs) find important applications in a number of areas. The diverse requirements for these applications are often demanding and challenging for the design and fabrication of SMMs. Here we report a new class of FeCoNi(AlSi)x (0 ≤ x ≤ 0.8 in molar ratio) SMMs based on high-entropy alloys (HEAs). It is found that with the compositional and structural changes, the optimal balance of magnetic, electrical, and mechanical properties is achieved at x = 0.2, for which the combination of saturation magnetization (1.15 T), coercivity (1,400 A/m), electrical resistivity (69.5 μΩ·cm), yield strength (342 MPa), and strain without fracture (50%) makes the alloy an excellent SMM. Ab initio calculations are used to explain the high magnetic saturation of the present HEAs and the effects of compositional structures on magnetic characteristics. The HEA-based SMMs point to new directions in both the application of HEAs and the search for novel SMMs. PMID:23492734
[Computational chemistry in structure-based drug design].
Cao, Ran; Li, Wei; Sun, Han-Zi; Zhou, Yu; Huang, Niu
2013-07-01
Today, the understanding of the sequence and structure of biologically relevant targets is growing rapidly and researchers from many disciplines, physics and computational science in particular, are making significant contributions to modern biology and drug discovery. However, it remains challenging to rationally design small molecular ligands with desired biological characteristics based on the structural information of the drug targets, which demands more accurate calculation of ligand binding free-energy. With the rapid advances in computer power and extensive efforts in algorithm development, physics-based computational chemistry approaches have played more important roles in structure-based drug design. Here we reviewed the newly developed computational chemistry methods in structure-based drug design as well as the elegant applications, including binding-site druggability assessment, large scale virtual screening of chemical database, and lead compound optimization. Importantly, here we address the current bottlenecks and propose practical solutions.
Cotton-based Cellulose Nanomaterials for Applications in Composites and Electronics
NASA Astrophysics Data System (ADS)
Farahbakhsh, Nasim
A modern society demands development of highly valued and sustainable products via innovative process technologies and utilizing bio-based alternatives for petroleum based materials. Systematic comparative study of nanocellulose particles as a biodegradable and renewable reinforcing agent can help to develop criteria for selecting an appropriate candidate to be incorporated in polymer nanocomposites. Of particular interest has been nanocellulosic materials including cellulose nanocrystal (CNC) and micro/nanofibrilated cellulose (MFC/NFC) which possess a hierarchical structure that permits an ordered structure with unique properties that has served as building blocks for the design of green and novel materials composites for applications in flexible electronics, medicine and composites. Key differences exist in nanocellulosic materials as a result the process by which the material is produced. This research demonstrates the applicability for the use of recycled cotton as promising sustainable material to be utilized as a substrate for electronic application and a reinforcing agent choice that can be produced without any intensive purification process and be applied to synthetic-based polymer nanocomposites in melt-processing. (Abstract shortened by ProQuest.).
Textile Technologies and Tissue Engineering: A Path Towards Organ Weaving
Akbari, Mohsen; Tamayol, Ali; Bagherifard, Sara; Serex, Ludovic; Mostafalu, Pooria; Faramarzi, Negar; Mohammadi, Mohammad Hossein
2016-01-01
Textile technologies have recently attracted great attention as potential biofabrication tools for engineering tissue constructs. Using current textile technologies, fibrous structures can be designed and engineered to attain the required properties that are demanded by different tissue engineering applications. Several key parameters such as physiochemical characteristics of fibers, pore size and mechanical properties of the fabrics play important role in the effective use of textile technologies in tissue engineering. This review summarizes the current advances in the manufacturing of biofunctional fibers. Different textile methods such as knitting, weaving, and braiding are discussed and their current applications in tissue engineering are highlighted. PMID:26924450
Feasibility of magnetic bearings for advanced gas turbine engines
NASA Technical Reports Server (NTRS)
Hibner, David; Rosado, Lewis
1992-01-01
The application of active magnetic bearings to advanced gas turbine engines will provide a product with major improvements compared to current oil lubricated bearing designs. A rethinking of the engine rotating and static structure design is necessary and will provide the designer with significantly more freedom to meet the demanding goals of improved performance, increased durability, higher reliability, and increased thrust to weight ratio via engine weight reduction. The product specific technology necessary for this high speed, high temperature, dynamically complex application has been defined. The resulting benefits from this approach to aircraft engine rotor support and the complementary engine changes and improvements have been assessed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Doyle, T W; Shugart, H H; West, D C
1981-01-01
This study examines the utilization and management of natural forest lands to meet growing wood-energy demands. An application of a forest simulation model is described for assessing energy returns and long-term ecological impacts of wood-energy harvesting under four general silvicultural practices. Results indicate that moderate energy yields could be expected from mild cutting operations which would significantly effect neither the commercial timber market nor the composition, structure, or diversity of these forests. Forest models can provide an effective tool for determining optimal management strategies that maximize energy returns, minimize environmental detriment, and complement existing land-use plans.
Wang, Guan-E; Xu, Gang; Wang, Ming-Sheng; Cai, Li-Zhen; Li, Wen-Hua; Guo, Guo-Cong
2015-12-01
Single-component white light materials may create great opportunities for novel conventional lighting applications and display systems; however, their reported color rendering index (CRI) values, one of the key parameters for lighting, are less than 90, which does not satisfy the demand of color-critical upmarket applications, such as photography, cinematography, and art galleries. In this work, two semiconductive chloroplumbate (chloride anion of lead(ii)) hybrids, obtained using a new inorganic-organic hybrid strategy, show unprecedented 3-D inorganic framework structures and white-light-emitting properties with high CRI values around 90, one of which shows the highest value to date.
On-demand drawing of high aspect-ratio, microsphere-tipped elastomeric micropillars
NASA Astrophysics Data System (ADS)
Li, Qiang; Kim, Jaeyoun
2017-08-01
High aspect-ratio elastomeric micropillars are widely used in a plethora of applications, such as functional surfaces, actuators, and sensors. Their fabrication at arbitrary positions on non-planar substrates, however, has rarely been reported. Here we demonstrate a new technique for facile fabrication of high aspect-ratio, microsphere-tipped elastomeric micropillars on structures with uncommon geometries. As a proof-of-concept exemplary application, a fiber optic contact sensor is realized by integrating a micropillar onto the end facet of an optical fiber. Overall, both the fabrication technique and the resulting outcomes of this work will add new tools to the toolbox of soft-MEMS and softrobotics.
Development of low-cost high-performance multispectral camera system at Banpil
NASA Astrophysics Data System (ADS)
Oduor, Patrick; Mizuno, Genki; Olah, Robert; Dutta, Achyut K.
2014-05-01
Banpil Photonics (Banpil) has developed a low-cost high-performance multispectral camera system for Visible to Short- Wave Infrared (VIS-SWIR) imaging for the most demanding high-sensitivity and high-speed military, commercial and industrial applications. The 640x512 pixel InGaAs uncooled camera system is designed to provide a compact, smallform factor to within a cubic inch, high sensitivity needing less than 100 electrons, high dynamic range exceeding 190 dB, high-frame rates greater than 1000 frames per second (FPS) at full resolution, and low power consumption below 1W. This is practically all the feature benefits highly desirable in military imaging applications to expand deployment to every warfighter, while also maintaining a low-cost structure demanded for scaling into commercial markets. This paper describes Banpil's development of the camera system including the features of the image sensor with an innovation integrating advanced digital electronics functionality, which has made the confluence of high-performance capabilities on the same imaging platform practical at low cost. It discusses the strategies employed including innovations of the key components (e.g. focal plane array (FPA) and Read-Out Integrated Circuitry (ROIC)) within our control while maintaining a fabless model, and strategic collaboration with partners to attain additional cost reductions on optics, electronics, and packaging. We highlight the challenges and potential opportunities for further cost reductions to achieve a goal of a sub-$1000 uncooled high-performance camera system. Finally, a brief overview of emerging military, commercial and industrial applications that will benefit from this high performance imaging system and their forecast cost structure is presented.
Wei, Qiulong; Xiong, Fangyu; Tan, Shuangshuang; Huang, Lei; Lan, Esther H; Dunn, Bruce; Mai, Liqiang
2017-05-01
Electrochemical energy storage technology is of critical importance for portable electronics, transportation and large-scale energy storage systems. There is a growing demand for energy storage devices with high energy and high power densities, long-term stability, safety and low cost. To achieve these requirements, novel design structures and high performance electrode materials are needed. Porous 1D nanomaterials which combine the advantages of 1D nanoarchitectures and porous structures have had a significant impact in the field of electrochemical energy storage. This review presents an overview of porous 1D nanostructure research, from the synthesis by bottom-up and top-down approaches with rational and controllable structures, to several important electrochemical energy storage applications including lithium-ion batteries, sodium-ion batteries, lithium-sulfur batteries, lithium-oxygen batteries and supercapacitors. Highlights of porous 1D nanostructures are described throughout the review and directions for future research in the field are discussed at the end. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
DOT National Transportation Integrated Search
2017-07-04
The primary objective of this project is to develop multiple simulation testbeds/transportation models to evaluate the impacts of Dynamic Mobility Application (DMA) connected vehicle applications and Active Transportation and Demand management (ATDM)...
NASA Astrophysics Data System (ADS)
Kung, Chun Haow; Zahiri, Beniamin; Sow, Pradeep Kumar; Mérida, Walter
2018-06-01
A copper mesh with dendritic copper-oxide core-shell structure is prepared using an additive-free electrochemical deposition strategy for on-demand oil-water separation. Electrochemical manipulation of the oxidation state of the copper oxide shell phase results in opposite affinities towards water and oil. The copper mesh can be tuned to manifest both superhydrophobic and superoleophilic properties to enable oil-removal. Conversely, switching to superhydrophilic and underwater superoleophobic allows water-removal. These changes correspond to the application of small reduction voltages (<1.5 V) and subsequent air drying. In the oil-removal mode, heavy oil selectively passes through the mesh while water is retained; in water-removal mode, the mesh allows water to permeate but blocks light oil. The smart membrane achieved separation efficiencies higher than 98% for a series of oil-water mixtures. The separation efficiency remains high with less than 5% variation after 30 cycles of oil-water separation in both modes. The switchable wetting mechanism is demonstrated with the aid of microstructural and electrochemical analysis and based on the well-known Cassie-Baxter and Wenzel theories. The selective removal of water or oil from the oil-water mixtures is driven solely by gravity and yields high efficiency and recyclability. The potential applications for the relevant technologies include oil spills cleanup, fuel purification, and wastewater treatment.
NASA Astrophysics Data System (ADS)
Rankin, Alasdair; McGarry, Steven
2018-01-01
The unique and tunable optical properties of metal nanoparticles have attracted intense and sustained academic attention in recent years. In tandem with the demand for low-cost responsive materials, one particular topic of interest is the development of mechanically responsive device structures. This work describes the design, fabrication, and testing of a mechanically responsive plasmonic device structure that has been integrated onto a standard commercial plastic substrate. With a low actuation force and a visually perceivable color shift, this device would be attractive for applications requiring responsive features that can be activated by the human hand.
Affordable Manufacturing Technologies Being Developed for Actively Cooled Ceramic Components
NASA Technical Reports Server (NTRS)
Bhatt, Ramakrishna T.
1999-01-01
Efforts to improve the performance of modern gas turbine engines have imposed increasing service temperature demands on structural materials. Through active cooling, the useful temperature range of nickel-base superalloys in current gas turbine engines has been extended, but the margin for further improvement appears modest. Because of their low density, high-temperature strength, and high thermal conductivity, in situ toughened silicon nitride ceramics have received a great deal of attention for cooled structures. However, high processing costs have proven to be a major obstacle to their widespread application. Advanced rapid prototyping technology, which is developing rapidly, offers the possibility of an affordable manufacturing approach.
Nano-sized structures for the detection of food components and contaminants.
Dudak, Fahriye Ceyda; Bas, Deniz; Basaran-Akgul, Nese; Tamer, Ugur; Boyaci, Ismail Hakki
2011-06-01
New methods to identify trace amount of food components and/or contaminants (infectious pathogens and chemicals) rapidly, accurately, and with high sensitivity are in constant demand to prevent foodborne illnesses. Multipurpose biofunctionalized engineered nanomaterials are very promising for the detection of food components and contaminants. The unique optical and magnetic properties of the nanoscale materials are very useful in the analysis of food. The objectives of this review paper are to discuss the development of applications of nanoscale structures related to food industries and to provide an overview of available methods of detecting food components and contaminants with particular emphasis on the use of nanoparticles.
Structures and Mechanical Properties of Natural and Synthetic Diamonds
NASA Technical Reports Server (NTRS)
Miyoshi, Kazuhisa
1998-01-01
A revolution in the diamond technology is in progress, as the low-pressure process becomes an industrial reality. It will soon be possible to take advantage of the demanding properties of diamond to develop a myriad of new applications, particularly for self-lubricating, wear-resistant, and superhard coatings. The production of large diamond films or sheets at low cost, a distinct possibility in the not-too-distant future, may drastically change tribology technology, particularly regarding solid lubricants and lubricating materials and systems. This paper reviews the structures and properties of natural and synthetic diamonds to gain a better understanding of the tribological properties of diamond and related materials. Atomic and crystal structure, impurities, mechanical properties, and indentation hardness of diamond are described.
DOT National Transportation Integrated Search
1982-08-01
This report discusses the level and nature of world motor vehicle demand for the period 1980-1990. A general understanding of the structure of motor vehicle demand is developed. Published demand forecasts, varying widely, are gathered and their discr...
Idris, Mohd Awang; Dollard, Maureen F; Winefield, Anthony H
2011-01-01
To examine the impact of globalization on employee psychological health and job satisfaction via job characteristics (i.e., job demands and job resources) in an emerging economy, that of Malaysia. As external factors are regarded as influences on the working environment, we hypothesized that global forces (increased pressure and competition) would have an impact on burnout and job satisfaction via increased demands (role conflict, emotional demands) and reduced resources (supervisor support, coworkers support). Data were collected using a population based survey among 308 employees in the state of Selangor, Malaysia. Participants were approached at home during the weekend or on days off from work. Only one participant was selected per household. Structural equation modelling was used to analyse the data. Nearly 54% of respondents agreed that they need to work harder, 25% agreed that their job was not secure and 24% thought they had lost power and control on the job due to global trade competition. Consistent with our predictions, demands mediated the globalization to burnout relationship, and resources mediated the globalization to job satisfaction relationship. Together, these results support the idea that external factors influence work conditions and in turn employee health and job satisfaction. We conclude that the jobs demands-resources framework is applicable in an Eastern setting and that globalization is a key antecedent of working environments.
Weather and age-gender effects on the projection of future emergency ambulance demand in Hong Kong.
Lai, Poh-Chin; Wong, Ho-Ting
2015-03-01
An accurate projection for ambulance demand is essential to enable better resource planning for the future that strives to either maintain current levels of services or reconsider future standards and expectations. More than 2 million cases of emergency room attendance in 2008 were obtained from the Hong Kong Hospital Authority to project the demand for its ambulance services in 2036. The projection of ambulance demand in 2036 was computed in consideration of changes in the age-gender structure between 2008 and 2036. The quadratic relation between average daily temperature and daily ambulance demand in 2036 was further explored by including and excluding age-gender demographic changes. Without accounting for changes in the age-gender structure, the 2036 ambulance demand for age groups of 65 and above were consistently underestimated (by 38%-65%), whereas those of younger age groups were overestimated (by 6%-37%). Moreover, changes in the 2008 to 2036 age-gender structure also shift upward and emphasize relationships between average daily temperature and daily ambulance demand at both ends of the quadratic U-shaped curve. Our study reveals a potential societal implication of ageing population on the demand for ambulance services. © 2012 APJPH.
Ul-Islam, Mazhar; Khan, Shaukat; Ullah, Muhammad Wajid; Park, Joong Kon
2015-12-01
Bacterial cellulose (BC), owing to its pure nature and impressive physicochemical properties, including high mechanical strength, crystallinity, porous fibrous structure, and liquid absorbing capabilities, has emerged as an advanced biomaterial. To match the market demand and economic values, BC has been produced through a number of synthetic routes, leading to slightly different structural features and physical appearance. Chemical nature, porous geometry, and 3D fibrous structure of BC make it an ideal material for composites synthesis that successfully overcome certain deficiencies of pure BC. In this review, we have focused various strategies developed for synthesizing BC and BC composites. Reinforcement materials including nanoparticles and polymers have enhanced the antimicrobial, conducting, magnetic, biocompatible, and mechanical properties of BC. Both pure BC and its composites have shown impressive applications in medical fields and in the development of optoelectronic devices. Herein, we have given a special attention to discuss its applications in the medical and electronic fields. In conclusion, BC and BC composites have realistic potential to be used in future development of medical devices, artificial organs and electronic and conducting materials. The contents discussed herein will provide an eye-catching theme to the researchers concerned with practical applications of BC and BC composites. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Development of a High-Sensitivity Wireless Accelerometer for Structural Health Monitoring
Zhu, Li; Fu, Yuguang; Chow, Raymond; Spencer, Billie F.; Park, Jong Woong; Mechitov, Kirill
2018-01-01
Structural health monitoring (SHM) is playing an increasingly important role in ensuring the safety of structures. A shift of SHM research away from traditional wired methods toward the use of wireless smart sensors (WSS) has been motivated by the attractive features of wireless smart sensor networks (WSSN). The progress achieved in Micro Electro-Mechanical System (MEMS) technologies and wireless data transmission, has extended the effectiveness and range of applicability of WSSNs. One of the most common sensors employed in SHM strategies is the accelerometer; however, most accelerometers in WSS nodes have inadequate resolution for measurement of the typical accelerations found in many SHM applications. In this study, a high-resolution and low-noise tri-axial digital MEMS accelerometer is incorporated in a next-generation WSS platform, the Xnode. In addition to meeting the acceleration sensing demands of large-scale civil infrastructure applications, this new WSS node provides powerful hardware and a robust software framework to enable edge computing that can deliver actionable information. Hardware and software integration challenges are presented, and the associate resolutions are discussed. The performance of the wireless accelerometer is demonstrated experimentally through comparison with high-sensitivity wired accelerometers. This new high-sensitivity wireless accelerometer will extend the use of WSSN to a broader class of SHM applications. PMID:29342102
Development of a High-Sensitivity Wireless Accelerometer for Structural Health Monitoring.
Zhu, Li; Fu, Yuguang; Chow, Raymond; Spencer, Billie F; Park, Jong Woong; Mechitov, Kirill
2018-01-17
Structural health monitoring (SHM) is playing an increasingly important role in ensuring the safety of structures. A shift of SHM research away from traditional wired methods toward the use of wireless smart sensors (WSS) has been motivated by the attractive features of wireless smart sensor networks (WSSN). The progress achieved in Micro Electro-Mechanical System (MEMS) technologies and wireless data transmission, has extended the effectiveness and range of applicability of WSSNs. One of the most common sensors employed in SHM strategies is the accelerometer; however, most accelerometers in WSS nodes have inadequate resolution for measurement of the typical accelerations found in many SHM applications. In this study, a high-resolution and low-noise tri-axial digital MEMS accelerometer is incorporated in a next-generation WSS platform, the Xnode. In addition to meeting the acceleration sensing demands of large-scale civil infrastructure applications, this new WSS node provides powerful hardware and a robust software framework to enable edge computing that can deliver actionable information. Hardware and software integration challenges are presented, and the associate resolutions are discussed. The performance of the wireless accelerometer is demonstrated experimentally through comparison with high-sensitivity wired accelerometers. This new high-sensitivity wireless accelerometer will extend the use of WSSN to a broader class of SHM applications.
NASA Astrophysics Data System (ADS)
Ruan, Dianbo; Kim, Myeong-Seong; Yang, Bin; Qin, Jun; Kim, Kwang-Bum; Lee, Sang-Hyun; Liu, Qiuxiang; Tan, Lei; Qiao, Zhijun
2017-10-01
To address the large-scale application demands of high energy density, high power density, and long cycle lifetime, 700-F hybrid capacitor pouch cells have been prepared, comprising ∼240-μm-thick activated carbon cathodes, and ∼60-μm-thick Li4Ti5O12 anodes. Microspherical Li4Ti5O12 (M-LTO) synthesized by spray-drying features 200-400 nm primary particles and interconnected nanopore structures. M-LTO half-cells exhibits high specific capacities (175 mAhh g-1), good rate capabilities (148 mAhh g-1 at 20 C), and ultra-long cycling stabilities (90% specific capacity retention after 10,000 cycles). In addition, the obtained hybrid capacitors comprising activated carbon (AC) and M-LTO shows excellent cell performances, achieving a maximum energy density of 51.65 Wh kg-1, a maximum power density of 2466 W kg-1, and ∼92% capacitance retention after 10,000 cycles, thus meeting the demands for large-scale applications such as trolleybuses.
NASA Astrophysics Data System (ADS)
Furlong, Cosme; Pryputniewicz, Ryszard J.
1998-05-01
Increased demands on the performance and efficiency of mechanical components impose challenges on their engineering design and optimization, especially when new and more demanding applications must be developed in relatively short periods of time while satisfying design objectives, as well as cost and manufacturability. In addition, reliability and durability must be taken into consideration. As a consequence, effective quantitative methodologies, computational and experimental, should be applied in the study and optimization of mechanical components. Computational investigations enable parametric studies and the determination of critical engineering design conditions, while experimental investigations, especially those using optical techniques, provide qualitative and quantitative information on the actual response of the structure of interest to the applied load and boundary conditions. We discuss a hybrid experimental and computational approach for investigation and optimization of mechanical components. The approach is based on analytical, computational, and experimental resolutions methodologies in the form of computational, noninvasive optical techniques, and fringe prediction analysis tools. Practical application of the hybrid approach is illustrated with representative examples that demonstrate the viability of the approach as an effective engineering tool for analysis and optimization.
Mehta, Deepika; Satyanarayana, Tulasi
2016-01-01
Industrial enzyme market has been projected to reach US$ 6.2 billion by 2020. Major reasons for continuous rise in the global sales of microbial enzymes are because of increase in the demand for consumer goods and biofuels. Among major industrial enzymes that find applications in baking, alcohol, detergent, and textile industries are α-amylases. These are produced by a variety of microbes, which randomly cleave α-1,4-glycosidic linkages in starch leading to the formation of limit dextrins. α-Amylases from different microbial sources vary in their properties, thus, suit specific applications. This review focuses on the native and recombinant α-amylases from bacteria and archaea, their production and the advancements in the molecular biology, protein engineering and structural studies, which aid in ameliorating their properties to suit the targeted industrial applications. PMID:27516755
Design and application of BIM based digital sand table for construction management
NASA Astrophysics Data System (ADS)
Fuquan, JI; Jianqiang, LI; Weijia, LIU
2018-05-01
This paper explores the design and application of BIM based digital sand table for construction management. Aiming at the demands and features of construction management plan for bridge and tunnel engineering, the key functional features of digital sand table should include three-dimensional GIS, model navigation, virtual simulation, information layers, and data exchange, etc. That involving the technology of 3D visualization and 4D virtual simulation of BIM, breakdown structure of BIM model and project data, multi-dimensional information layers, and multi-source data acquisition and interaction. Totally, the digital sand table is a visual and virtual engineering information integrated terminal, under the unified data standard system. Also, the applications shall contain visual constructing scheme, virtual constructing schedule, and monitoring of construction, etc. Finally, the applicability of several basic software to the digital sand table is analyzed.
Mehta, Deepika; Satyanarayana, Tulasi
2016-01-01
Industrial enzyme market has been projected to reach US$ 6.2 billion by 2020. Major reasons for continuous rise in the global sales of microbial enzymes are because of increase in the demand for consumer goods and biofuels. Among major industrial enzymes that find applications in baking, alcohol, detergent, and textile industries are α-amylases. These are produced by a variety of microbes, which randomly cleave α-1,4-glycosidic linkages in starch leading to the formation of limit dextrins. α-Amylases from different microbial sources vary in their properties, thus, suit specific applications. This review focuses on the native and recombinant α-amylases from bacteria and archaea, their production and the advancements in the molecular biology, protein engineering and structural studies, which aid in ameliorating their properties to suit the targeted industrial applications.
Latent factor structure of a behavioral economic cigarette demand curve in adolescent smokers
Bidwell, L. Cinnamon; MacKillop, James; Murphy, James G.; Tidey, Jennifer W.; Colby, Suzanne M.
2012-01-01
Behavioral economic demand curves, or quantitative representations of drug consumption across a range of prices, have been used to assess motivation for a variety of drugs. Such curves generate multiple measures of drug demand that are associated with cigarette consumption and nicotine dependence. However, little is known about the relationships among these facets of demand. The aim of the study was to quantify these relationships in adolescent smokers by using exploratory factor analysis to examine the underlying structure of the facets of nicotine incentive value generated from a demand curve measure. Participants were 138 adolescent smokers who completed a hypothetical cigarette purchase task, which assessed estimated cigarette consumption at escalating levels of price/cigarette. Demand curves and five facets of demand were generated from the measure: Elasticity (i.e., 1/α or proportionate price sensitivity); Intensity (i.e., consumption at zero price); Omax (i.e., maximum financial expenditure on cigarettes); Pmax (i.e., price at which expenditure is maximized); and Breakpoint (i.e., the price that suppresses consumption to zero). Principal components analysis was used to examine the latent structure among the variables. The results revealed a two-factor solution, which were interpreted as “Persistence,” reflecting insensitivity to escalating price, and “Amplitude,” reflecting the absolute levels of consumption and price. These findings suggest a two factor structure of nicotine incentive value as measured via a demand curve. If supported, these findings have implications for understanding the relationships among individual demand indices in future behavioral economic studies and may further contribute to understanding of the nature of cigarette reinforcement. PMID:22727784
Wen, Jia-Long; Sun, Shao-Long; Xue, Bai-Liang; Sun, Run-Cang
2013-01-01
The demand for efficient utilization of biomass induces a detailed analysis of the fundamental chemical structures of biomass, especially the complex structures of lignin polymers, which have long been recognized for their negative impact on biorefinery. Traditionally, it has been attempted to reveal the complicated and heterogeneous structure of lignin by a series of chemical analyses, such as thioacidolysis (TA), nitrobenzene oxidation (NBO), and derivatization followed by reductive cleavage (DFRC). Recent advances in nuclear magnetic resonance (NMR) technology undoubtedly have made solution-state NMR become the most widely used technique in structural characterization of lignin due to its versatility in illustrating structural features and structural transformations of lignin polymers. As one of the most promising diagnostic tools, NMR provides unambiguous evidence for specific structures as well as quantitative structural information. The recent advances in two-dimensional solution-state NMR techniques for structural analysis of lignin in isolated and whole cell wall states (in situ), as well as their applications are reviewed. PMID:28809313
Mohamad, Mazmira; Ahmed, Rashid; Shaari, Amirudin; Goumri-Said, Souraya
2015-02-01
Escalating demand for sustainable energy resources, because of the rapid exhaustion of conventional energy resources as well as to maintain the environmental level of carbon dioxide (CO2) to avoid its adverse effect on the climate, has led to the exploitation of photovoltaic technology manifold more than ever. In this regard organic materials have attracted great attention on account of demonstrating their potential to harvest solar energy at an affordable rate for photovoltaic technology. 2-vinyl-4,5-dicyanoimidazole (vinazene) is considered as a suitable material over the fullerenes for photovoltaic applications because of its particular chemical and physical nature. In the present study, DFT approaches are employed to provide an exposition of optoelectronic properties of vinazene molecule and molecular crystal. To gain insight into its properties, different forms of exchange correlation energy functional/potential such as LDA, GGA, BLYP, and BL3YP are used. Calculated electronic structure of vinazene molecule has been displayed via HOMO-LUMO isosurfaces, whereas electronic structure of the vinazene molecular crystal, via electronic band structure, is presented. The calculated electronic and optical properties were analyzed and compared as well. Our results endorse vinazene as a suitable material for organic photovoltaic applications.
Brigl, B; Ammenwerth, E; Dujat, C; Gräber, S; Grosse, A; Häber, A; Jostes, C; Winter, A
2005-01-01
Systematic information management in hospitals demands for a strategic information management plan (SIM plan). As preparing a SIM plan is a considerable challenge we provide a practical guideline that is directly applicable when a SIM plan is going to be prepared. The guideline recommends a detailed structure of a SIM plan and gives advice about its content and the preparation process. It may be used as template, which can be adapted to the individual demands of any hospital. The guideline was used in several hospitals preparing a SIM plan. Experiences showed that the SIM plans could be prepared very efficiently and timely using the guideline, that the proposed SIM plan structure suited well, that the guideline offers enough flexibility to meet the requirements of the individual hospitals and that the specific recommendations of the guideline were very helpful. Nevertheless, we must strive for a more comprehensive theory of strategic information management planning which -- in the sense of enterprise architecture planning -- represents the intrinsic correlations of the different parts of a SIM plan to a greater extent.
ERIC Educational Resources Information Center
Weathersby, George B.
This paper argues that, in addition to responding to surface manifestations of imbalance in scientific manpower supply and demand, we should examine and understand far better than we now do the nature and extent of the structural forces operative on the supply and demand of scientific talent. The author reviewed the literature and the parameters…
Lim, Hooi Been; Baumann, Dirk; Li, Er-Ping
2011-03-01
Wireless body area network (WBAN) is a new enabling system with promising applications in areas such as remote health monitoring and interpersonal communication. Reliable and optimum design of a WBAN system relies on a good understanding and in-depth studies of the wave propagation around a human body. However, the human body is a very complex structure and is computationally demanding to model. This paper aims to investigate the effects of the numerical model's structure complexity and feature details on the simulation results. Depending on the application, a simplified numerical model that meets desired simulation accuracy can be employed for efficient simulations. Measurements of ultra wideband (UWB) signal propagation along a human arm are performed and compared to the simulation results obtained with numerical arm models of different complexity levels. The influence of the arm shape and size, as well as tissue composition and complexity is investigated.
Si light-emitting device in integrated photonic CMOS ICs
NASA Astrophysics Data System (ADS)
Xu, Kaikai; Snyman, Lukas W.; Aharoni, Herzl
2017-07-01
The motivation for integrated Si optoelectronics is the creation of low-cost photonics for mass-market applications. Especially, the growing demand for sensitive biochemical sensors in the environmental control or medicine leads to the development of integrated high resolution sensors. Here CMOS-compatible Si light-emitting device structures are presented for investigating the effect of various depletion layer profiles and defect engineering on the photonic transition in the 1.4-2.8 eV. A novel Si device is proposed to realize both a two-terminal Si-diode light-emitting device and a three-terminal Si gate-controlled diode light-emitting device in the same device structure. In addition to the spectral analysis, differences between two-terminal and three-terminal devices are discussed, showing the light emission efficiency change. The proposed Si optical source may find potential applications in micro-photonic systems and micro-optoelectro-mechanical systems (MOEMS) in CMOS integrated circuitry.
Parallel Adaptive Mesh Refinement Library
NASA Technical Reports Server (NTRS)
Mac-Neice, Peter; Olson, Kevin
2005-01-01
Parallel Adaptive Mesh Refinement Library (PARAMESH) is a package of Fortran 90 subroutines designed to provide a computer programmer with an easy route to extension of (1) a previously written serial code that uses a logically Cartesian structured mesh into (2) a parallel code with adaptive mesh refinement (AMR). Alternatively, in its simplest use, and with minimal effort, PARAMESH can operate as a domain-decomposition tool for users who want to parallelize their serial codes but who do not wish to utilize adaptivity. The package builds a hierarchy of sub-grids to cover the computational domain of a given application program, with spatial resolution varying to satisfy the demands of the application. The sub-grid blocks form the nodes of a tree data structure (a quad-tree in two or an oct-tree in three dimensions). Each grid block has a logically Cartesian mesh. The package supports one-, two- and three-dimensional models.
Control Structures for VSC-based FACTS Devices under Normal and Faulted AC-systems
NASA Astrophysics Data System (ADS)
Babaei, Saman
This thesis is concerned with improving the Flexible AC Transmission Systems (FACTS) devices performance under the normal and fault AC-system conditions by proposing new control structures and also converter topologies. The combination of the increasing electricity demand and restrictions in expanding the power system infrastructures has urged the utility owners to deploy the utility-scaled power electronics in the power system. Basically, FACTS is referred to the application of the power electronics in the power systems. Voltage Source Converter (VSC) is the preferred building block of the FACTS devices and many other utility-scale power electronics applications. Despite of advances in the semiconductor technology and ultra-fast microprocessor based controllers, there are still many issues to address and room to improve[25]. An attempt is made in this thesis to address these important issues of the VSC-based FACTS devices and provide solutions to improve them.
Photonic integrated circuits based on sampled-grating distributed-Bragg-reflector lasers
NASA Astrophysics Data System (ADS)
Barton, Jonathon S.; Skogen, Erik J.; Masanovic, Milan L.; Raring, James; Sysak, Matt N.; Johansson, Leif; DenBaars, Steven P.; Coldren, Larry A.
2003-07-01
The Sampled-Grating Distributed-Bragg-Reflector laser(SGDBR) provides wide tunability (>40nm), and high output power (>10mW). Driven by the demand for network reconfigurability and ease of implementation, the SGDBR has moved from the research lab to be commercially viable in the marketplace. The SGDBR is most often implemented using an offset-quantum well epitaxial structure in which the quantum wells are etched off in the passive sections. Alternatively, quantum well intermixing has been used recently to achieve the same goal - resulting in improved optical gain and the potential for multiple bandgaps along the device structure. These epitaxial "platforms" provide the basis for more exotic opto-electronic device functionality exhibiting low chirp for digital applications and enhanced linearity for analog applications. This talk will cover state-of-the-art opto-electronic devices based on the SGDBR platform including: integrated Mach-Zehnder modulators, and integrated electro-absorption modulators.
NASA Astrophysics Data System (ADS)
Medvigy, D.; Levy, J.; Xu, X.; Batterman, S. A.; Hedin, L.
2013-12-01
Ecosystems, by definition, involve a community of organisms. These communities generally exhibit heterogeneity in their structure and composition as a result of local variations in climate, soil, topography, disturbance history, and other factors. Climate-driven shifts in ecosystems will likely include an internal re-organization of community structure and composition and as well as the introduction of novel species. In terms of vegetation, this ecosystem heterogeneity can occur at relatively small scales, sometimes of the order of tens of meters or even less. Because this heterogeneous landscape generally has a variable and nonlinear response to environmental perturbations, it is necessary to carefully aggregate the local competitive dynamics between individual plants to the large scales of tens or hundreds of kilometers represented in climate models. Accomplishing this aggregation in a computationally efficient way has proven to be an extremely challenging task. To meet this challenge, the Ecosystem Demography 2 (ED2) model statistically characterizes a distribution of local resource environments, and then simulates the competition between individuals of different sizes and species (or functional groupings). Within this framework, it is possible to explicitly simulate the impacts of climate change on ecosystem structure and composition, including both internal re-organization and the introduction of novel species or functional groups. This presentation will include several illustrative applications of the evolution of ecosystem structure and composition under climate change. One application pertains to the role of nitrogen-fixing species in tropical forests. Will increasing CO2 concentrations increase the demand for nutrients and perhaps give a competitive edge to nitrogen-fixing species? Will potentially warmer and drier conditions make some tropical forests more water-limited, reducing the demand for nitrogen, thereby giving a competitive advantage to non-nitrogen-fixing species? Will the response of nitrogen-fixing species to climate change be sensitive to local disturbance histories?
Improving long-term care provision: towards demand-based care by means of modularity
2010-01-01
Background As in most fields of health care, societal and political changes encourage suppliers of long-term care to put their clients at the center of care and service provision and become more responsive towards client needs and requirements. However, the diverse, multiple and dynamic nature of demand for long-term care complicates the movement towards demand-based care provision. This paper aims to advance long-term care practice and, to that end, examines the application of modularity. This concept is recognized in a wide range of product and service settings for its ability to design demand-based products and processes. Methods Starting from the basic dimensions of modularity, we use qualitative research to explore the use and application of modularity principles in the current working practices and processes of four organizations in the field of long-term care for the elderly. In-depth semi-structured interviews were conducted with 38 key informants and triangulated with document research and observation. Data was analyzed thematically by means of coding and subsequent exploration of patterns. Data analysis was facilitated by qualitative analysis software. Results Our data suggest that a modular setup of supply is employed in the arrangement of care and service supply and assists providers of long-term care in providing their clients with choice options and variation. In addition, modularization of the needs assessment and package specification process allows the case organizations to manage client involvement but still provide customized packages of care and services. Conclusion The adequate setup of an organization's supply and its specification phase activities are indispensible for long-term care providers who aim to do better in terms of quality and efficiency. Moreover, long-term care providers could benefit from joint provision of care and services by means of modular working teams. Based upon our findings, we are able to elaborate on how to further enable demand-based provision of long-term care by means of modularity. PMID:20858256
Improving long-term care provision: towards demand-based care by means of modularity.
de Blok, Carolien; Luijkx, Katrien; Meijboom, Bert; Schols, Jos
2010-09-21
As in most fields of health care, societal and political changes encourage suppliers of long-term care to put their clients at the center of care and service provision and become more responsive towards client needs and requirements. However, the diverse, multiple and dynamic nature of demand for long-term care complicates the movement towards demand-based care provision. This paper aims to advance long-term care practice and, to that end, examines the application of modularity. This concept is recognized in a wide range of product and service settings for its ability to design demand-based products and processes. Starting from the basic dimensions of modularity, we use qualitative research to explore the use and application of modularity principles in the current working practices and processes of four organizations in the field of long-term care for the elderly. In-depth semi-structured interviews were conducted with 38 key informants and triangulated with document research and observation. Data was analyzed thematically by means of coding and subsequent exploration of patterns. Data analysis was facilitated by qualitative analysis software. Our data suggest that a modular setup of supply is employed in the arrangement of care and service supply and assists providers of long-term care in providing their clients with choice options and variation. In addition, modularization of the needs assessment and package specification process allows the case organizations to manage client involvement but still provide customized packages of care and services. The adequate setup of an organization's supply and its specification phase activities are indispensible for long-term care providers who aim to do better in terms of quality and efficiency. Moreover, long-term care providers could benefit from joint provision of care and services by means of modular working teams. Based upon our findings, we are able to elaborate on how to further enable demand-based provision of long-term care by means of modularity.
Application of Demand Analysis in Marketing Continuing Education.
ERIC Educational Resources Information Center
Waters, Elzberry, Jr.
This study investigated the feasibility of applying economic demand analysis (especially elasticity of demand) in marketing George Washington University off-campus degree programs. In the case under study, a supplemental budget request had to be submitted to meet expenses incurred by an unforeseen increase in demand for graduate and undergraduate…
Damage-Tolerant Polymer Composite Systems
NASA Astrophysics Data System (ADS)
Reifsnider, Kenneth L.
1988-11-01
One of the reasons for the rapid growth in the application of polymer composites is the opportunity they provide for the design and construction of composite structures that are especially resistant to losses of strength or reduced life resulting from damage during service. The usefulness of such materials is enhanced by the variety of reinforcement schemes that can be chosen to reflect specific service conditions. Under cyclic loading and demanding mechanical situations (e.g., helicopter parts, vehicle springs and high-speed rotors), polymer composites are considerably superior to competing materials.
Laser-powered dielectric-structures for the production of high-brightness electron and x-ray beams
NASA Astrophysics Data System (ADS)
Travish, Gil; Yoder, Rodney B.
2011-05-01
Laser powered accelerators have been under intensive study for the past decade due to their promise of high gradients and leveraging of rapid technological progress in photonics. Of the various acceleration schemes under examination, those based on dielectric structures may enable the production of relativistic electron beams in breadbox sized systems. When combined with undulators having optical-wavelength periods, these systems could produce high brilliance x-rays which find application in, for instance, medical and industrial imaging. These beams also may open the way for table-top atto-second sciences. Development and testing of these dielectric structures faces a number of challenges including complex beam dynamics, new demands on lasers and optical coupling, beam injection schemes, and fabrication. We describe one approach being pursued at UCLA-the Micro Accelerator Platform (MAP). A structure similar to the MAP has also been designed which produces periodic deflections and acts as an undulator for radiation production, and the prospects for this device will be considered. The lessons learned from the multi-year effort to realize these devices will be presented. Challenges remain with acceleration of sub-relativistic beams, focusing, beam phase stability and extension of these devices to higher beam energies. Our progress in addressing these hurdles will be summarized. Finally, the demands on laser technology and optical coupling will be detailed.
NASA Astrophysics Data System (ADS)
Aziz, Nurul Liyana Abdul; Aizam, Nur Aidya Hanum
2017-08-01
Course timetabling problem receives the highlight at the beginning of every semester. The problem is mainly on assigning courses to timeslot, rooms and lecturers which involving a set of rules and policies constraints. Generally, researchers present different features to signify their own universities' timetable according to the structure and behavior of their institution. However, the gap between theory and real-world applications that can be seen in the resulted timetable is the lacking of acknowledging human preferences. As to overcome this, it is very important to consider all the demands and preferences from timetabling community. This research therefore tries to accommodate the problem by investigating through surveys to several universities in the east coast of Malaysia the demands and preferences of individuals involved directly. Results from the questionnaires will be analyzed by using SPSS and all current issues regarding the demands will be included into our existing general university course timetabling mathematical model. The new university course timetabling mathematical model could best represent universities and be useful, especially in universities in Malaysia.
Economic aspects of metals recover
NASA Astrophysics Data System (ADS)
Wieczorek, Daria; Kwaśniewska, Dobrawa
2018-03-01
One of the modern economy models is circular economy in which wastes should be considered as resource and used in an efficient and sustainable way. This also concerns to metals included in scraps. However, the need for metal recovery from waste is not only the result of the latest economic trends but also the result of large and constantly changing demand for metals. Shrinking natural sources of metals, concentrations of ores in small number of countries in the world and resulting from this dependence on import, geopolitical situation, new technologies demands are only a few most important determinants that have been changing the structure of the metal market over years. In this chapter, authors focused on the presentation of economic aspects of metal recovery from various sources. The chapter presents the characteristic of metal market elements (supply, demand and price) and changes that took place over decades, underlining the structure of precious and highly desirable metal market elements. Balance between the demand and supply ensures price stability and rationalizes inflation. However, growing demand on many means that secure supply chains, such as recycling and material recovery, are essential to ensure continuity in the supply chain and guarantee unrestricted technological progress and innovation. The data included in this chapter presents also the concentration of different metals and group of metals in wastes pointing that recycling of waste can become one of the possibilities of acquiring missing and critical metals. Metal-laden wastes include a few groups: waste electrical and electronic equipments, catalysts of different application, introduced on chemical, petrochemical or automotive market, galvanic wastes and wastewaters. The profitability assessment of recycling processes is very complicated. Nevertheless cited data shows that profitability of recovery depends on the metal analyzed and the type of waste. It must be underline that an optimized management of wastes is of a great importance for the global economy and allow achieving not only economic but also environmental and social benefits.
Feasibility of groundwater recharge dam projects in arid environments
NASA Astrophysics Data System (ADS)
Jaafar, H. H.
2014-05-01
A new method for determining feasibility and prioritizing investments for agricultural and domestic recharge dams in arid regions is developed and presented. The method is based on identifying the factors affecting the decision making process and evaluating these factors, followed by determining the indices in a GIS-aided environment. Evaluated parameters include results from field surveys and site visits, land cover and soils data, precipitation data, runoff data and modeling, number of beneficiaries, domestic irrigation demand, reservoir objectives, demography, reservoirs yield and reliability, dam structures, construction costs, and operation and maintenance costs. Results of a case study on more than eighty proposed dams indicate that assessment of reliability, annualized cost/demand satisfied and yield is crucial prior to investment decision making in arid areas. Irrigation demand is the major influencing parameter on yield and reliability of recharge dams, even when only 3 months of the demand were included. Reliability of the proposed reservoirs as related to their standardized size and net inflow was found to increase with increasing yield. High priority dams were less than 4% of the total, and less priority dams amounted to 23%, with the remaining found to be not feasible. The results of this methodology and its application has proved effective in guiding stakeholders for defining most favorable sites for preliminary and detailed design studies and commissioning.
DOT National Transportation Integrated Search
1980-11-01
The purpose of the Application Area Definition task is to define the travel demands and guideway networks for a set of representative AGT system deployments. These demands and networks, when combined with detailed descriptions of the systems and thei...
Evolutionary flight and enabling smart actuator devices
NASA Astrophysics Data System (ADS)
Manzo, Justin; Garcia, Ephrahim
2007-04-01
Recent interest in morphing vehicles with multiple, optimized configurations has led to renewed research on biological flight. The flying vertebrates - birds, bats, and pterosaurs - all made or make use of various morphing devices to achieve lift to suit rapidly changing flight demands, including maneuvers as complex as perching and hovering. The first part of this paper will discuss these devices, with a focus on the morphing elements and structural strong suits of each creature. Modern flight correlations to these devices will be discussed and analyzed as valid adaptations of these evolutionary traits. The second part of the paper will focus on the use of active joint structures for use in morphing aircraft devices. Initial work on smart actuator devices focused on NASA Langley's Hyper-Elliptical Cambered Span (HECS) wing platform, which led to development of a discretized spanwise curvature effector. This mechanism uses shape memory alloy (SMA) as the sole morphing actuator, allowing fast rotation with lightweight components at the expense of energy inefficiency. Phase two of morphing actuator development will add an element of active rigidity to the morphing structure, in the form of shape memory polymer (SMP). Employing a composite structure of polymer and alloy, this joint will function as part of a biomimetic morphing actuator system in a more energetically efficient manner. The joint is thermally actuated to allow compliance on demand and rigidity in the nominal configuration. Analytical and experimental joint models are presented, and potential applications on a bat-wing aircraft structure are outlined.
Latent factor structure of a behavioral economic cigarette demand curve in adolescent smokers.
Bidwell, L Cinnamon; MacKillop, James; Murphy, James G; Tidey, Jennifer W; Colby, Suzanne M
2012-11-01
Behavioral economic demand curves, or quantitative representations of drug consumption across a range of prices, have been used to assess motivation for a variety of drugs. Such curves generate multiple measures of drug demand that are associated with cigarette consumption and nicotine dependence. However, little is known about the relationships among these facets of demand. The aim of the study was to quantify these relationships in adolescent smokers by using exploratory factor analysis to examine the underlying structure of the facets of nicotine incentive value generated from a demand curve measure. Participants were 138 adolescent smokers who completed a hypothetical cigarette purchase task, which assessed estimated cigarette consumption at escalating levels of price/cigarette. Demand curves and five facets of demand were generated from the measure: Elasticity (i.e., 1/α or proportionate price sensitivity); Intensity (i.e., consumption at zero price); O(max) (i.e., maximum financial expenditure on cigarettes); P(max) (i.e., price at which expenditure is maximized); and Breakpoint (i.e., the price that suppresses consumption to zero). Principal components analysis was used to examine the latent structure among the variables. The results revealed a two-factor solution, which were interpreted as "Persistence," reflecting insensitivity to escalating price, and "Amplitude," reflecting the absolute levels of consumption and price. These findings suggest a two factor structure of nicotine incentive value as measured via a demand curve. If supported, these findings have implications for understanding the relationships among individual demand indices in future behavioral economic studies and may further contribute to understanding of the nature of cigarette reinforcement. Copyright © 2012 Elsevier Ltd. All rights reserved.
Do oil shocks predict economic policy uncertainty?
NASA Astrophysics Data System (ADS)
Rehman, Mobeen Ur
2018-05-01
Oil price fluctuations have influential role in global economic policies for developed as well as emerging countries. I investigate the role of international oil prices disintegrated into structural (i) oil supply shock, (ii) aggregate demand shock and (iii) oil market specific demand shocks, based on the work of Kilian (2009) using structural VAR framework on economic policies uncertainty of sampled markets. Economic policy uncertainty, due to its non-linear behavior is modeled in a regime switching framework with disintegrated structural oil shocks. Our results highlight that Indian, Spain and Japanese economic policy uncertainty responds to the global oil price shocks, however aggregate demand shocks fail to induce any change. Oil specific demand shocks are significant only for China and India in high volatility state.
NASA Astrophysics Data System (ADS)
Meglinski, Igor; Popov, Alexey; Bykov, Alexander
2017-03-01
Biophotonics-based diagnostic and imaging modalities have been widely used in various applications associated with the non-invasive imaging of the internal structure of a range biological media from a range of cells cultures to biological tissues. With the fast growing interest in food securities there remains strong demand to apply reliable and cost effective biophotonics-based technologies for rapid screening of freshness, internal defects and quality of major agricultural products. In current presentation the results of application of optical coherence tomography (OCT) and encapsulated optical bio-sensors for quantitative assessment of freshness of agricultural products, such as meat and sea foods, are presented, and their further perspectives are discussed.
Numerical grid generation in computational field simulations. Volume 1
DOE Office of Scientific and Technical Information (OSTI.GOV)
Soni, B.K.; Thompson, J.F.; Haeuser, J.
1996-12-31
To enhance the CFS technology to its next level of applicability (i.e., to create acceptance of CFS in an integrated product and process development involving multidisciplinary optimization) the basic requirements are: rapid turn-around time, reliable and accurate simulation, affordability and appropriate linkage to other engineering disciplines. In response to this demand, there has been a considerable growth in the grid generation related research activities involving automization, parallel processing, linkage with the CAD-CAM systems, CFS with dynamic motion and moving boundaries, strategies and algorithms associated with multi-block structured, unstructured, hybrid, hexahedral, and Cartesian grids, along with its applicability to various disciplinesmore » including biomedical, semiconductor, geophysical, ocean modeling, and multidisciplinary optimization.« less
Textile Technologies and Tissue Engineering: A Path Toward Organ Weaving.
Akbari, Mohsen; Tamayol, Ali; Bagherifard, Sara; Serex, Ludovic; Mostafalu, Pooria; Faramarzi, Negar; Mohammadi, Mohammad Hossein; Khademhosseini, Ali
2016-04-06
Textile technologies have recently attracted great attention as potential biofabrication tools for engineering tissue constructs. Using current textile technologies, fibrous structures can be designed and engineered to attain the required properties that are demanded by different tissue engineering applications. Several key parameters such as physiochemical characteristics of fibers, microarchitecture, and mechanical properties of the fabrics play important roles in the effective use of textile technologies in tissue engineering. This review summarizes the current advances in the manufacturing of biofunctional fibers. Different textile methods such as knitting, weaving, and braiding are discussed and their current applications in tissue engineering are highlighted. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Nose, Atsushi; Yamazaki, Tomohiro; Katayama, Hironobu; Uehara, Shuji; Kobayashi, Masatsugu; Shida, Sayaka; Odahara, Masaki; Takamiya, Kenichi; Matsumoto, Shizunori; Miyashita, Leo; Watanabe, Yoshihiro; Izawa, Takashi; Muramatsu, Yoshinori; Nitta, Yoshikazu; Ishikawa, Masatoshi
2018-04-24
We have developed a high-speed vision chip using 3D stacking technology to address the increasing demand for high-speed vision chips in diverse applications. The chip comprises a 1/3.2-inch, 1.27 Mpixel, 500 fps (0.31 Mpixel, 1000 fps, 2 × 2 binning) vision chip with 3D-stacked column-parallel Analog-to-Digital Converters (ADCs) and 140 Giga Operation per Second (GOPS) programmable Single Instruction Multiple Data (SIMD) column-parallel PEs for new sensing applications. The 3D-stacked structure and column parallel processing architecture achieve high sensitivity, high resolution, and high-accuracy object positioning.
Structures and Mechanical Properties of Natural and Synthetic Diamonds. Chapter 8
NASA Technical Reports Server (NTRS)
Miyoshi, Kazuhisa
1998-01-01
A revolution in diamond technology is in progress as the low-pressure process becomes an industrial reality. It will soon be possible to take advantage of the demanding properties of diamond to develop a myriad of new applications, particularly for self-lubricating, wear, and superhard coatings. The production of large diamond films or sheets at low cost, a distinct possibility in the not-too-distant future, may drastically change tribology technology, particularly solid lubricants and lubricating materials and systems. This chapter reviews the structures and properties of natural and synthetic diamond to gain a better understanding of the tribological properties of diamond and related materials to be described in the following chapters. Atomic and crystal structure, impurities, mechanical properties, and indentation hardness of diamond are described.
Lipases as biocatalysts for the synthesis of structured lipids.
Jala, Ram Chandra Reddy; Hu, Peng; Yang, Tiankui; Jiang, Yuanrong; Zheng, Yan; Xu, Xuebing
2012-01-01
Structured lipids (SL) are broadly referred to as modified or synthetic oils and fats or lipids with functional or pharmaceutical applications. Some structured lipids, such as triglycerides that contain both long-chain (mainly essential) fatty acids and medium- or short-chain fatty acids and also artificial products that mimic the structure of natural materials, namely human milk fat substitutes and cocoa butter equivalents, have been discussed. Further, other modified or synthetic lipids, such as structured phospholipids and synthetic phenolic lipids are also included in this chapter. For all the products described in this chapter, enzymatic production in industry has been already conducted in one way or another. Cocoa butter equivalents, healthy oil containing medium-chain fatty acids, phosphatidyl serine, and phenol lipids from enzyme technology have been reported for commercial operation. As the demand for better quality functional lipids is increasing, the production of structured lipids becomes an interesting area. Thus, in this chapter we have discussed latest developments as well as present industrial situation of all commercially important structured lipids.
Black Phosphorus and its Biomedical Applications
Choi, Jane Ru; Yong, Kar Wey; Choi, Jean Yu; Nilghaz, Azadeh; Lin, Yang; Xu, Jie; Lu, Xiaonan
2018-01-01
Black phosphorus (BP), also known as phosphorene, has attracted recent scientific attention since its first successful exfoliation in 2014 owing to its unique structure and properties. In particular, its exceptional attributes, such as the excellent optical and mechanical properties, electrical conductivity and electron-transfer capacity, contribute to its increasing demand as an alternative to graphene-based materials in biomedical applications. Although the outlook of this material seems promising, its practical applications are still highly challenging. In this review article, we discuss the unique properties of BP, which make it a potential platform for biomedical applications compared to other 2D materials, including graphene, molybdenum disulphide (MoS2), tungsten diselenide (WSe2) and hexagonal boron nitride (h-BN). We then introduce various synthesis methods of BP and review its latest progress in biomedical applications, such as biosensing, drug delivery, photoacoustic imaging and cancer therapies (i.e., photothermal and photodynamic therapies). Lastly, the existing challenges and future perspective of BP in biomedical applications are briefly discussed. PMID:29463996
High-performance scientific computing in the cloud
NASA Astrophysics Data System (ADS)
Jorissen, Kevin; Vila, Fernando; Rehr, John
2011-03-01
Cloud computing has the potential to open up high-performance computational science to a much broader class of researchers, owing to its ability to provide on-demand, virtualized computational resources. However, before such approaches can become commonplace, user-friendly tools must be developed that hide the unfamiliar cloud environment and streamline the management of cloud resources for many scientific applications. We have recently shown that high-performance cloud computing is feasible for parallelized x-ray spectroscopy calculations. We now present benchmark results for a wider selection of scientific applications focusing on electronic structure and spectroscopic simulation software in condensed matter physics. These applications are driven by an improved portable interface that can manage virtual clusters and run various applications in the cloud. We also describe a next generation of cluster tools, aimed at improved performance and a more robust cluster deployment. Supported by NSF grant OCI-1048052.
Scalable parallel distance field construction for large-scale applications
Yu, Hongfeng; Xie, Jinrong; Ma, Kwan -Liu; ...
2015-10-01
Computing distance fields is fundamental to many scientific and engineering applications. Distance fields can be used to direct analysis and reduce data. In this paper, we present a highly scalable method for computing 3D distance fields on massively parallel distributed-memory machines. Anew distributed spatial data structure, named parallel distance tree, is introduced to manage the level sets of data and facilitate surface tracking overtime, resulting in significantly reduced computation and communication costs for calculating the distance to the surface of interest from any spatial locations. Our method supports several data types and distance metrics from real-world applications. We demonstrate itsmore » efficiency and scalability on state-of-the-art supercomputers using both large-scale volume datasets and surface models. We also demonstrate in-situ distance field computation on dynamic turbulent flame surfaces for a petascale combustion simulation. In conclusion, our work greatly extends the usability of distance fields for demanding applications.« less
Scalable Parallel Distance Field Construction for Large-Scale Applications.
Yu, Hongfeng; Xie, Jinrong; Ma, Kwan-Liu; Kolla, Hemanth; Chen, Jacqueline H
2015-10-01
Computing distance fields is fundamental to many scientific and engineering applications. Distance fields can be used to direct analysis and reduce data. In this paper, we present a highly scalable method for computing 3D distance fields on massively parallel distributed-memory machines. A new distributed spatial data structure, named parallel distance tree, is introduced to manage the level sets of data and facilitate surface tracking over time, resulting in significantly reduced computation and communication costs for calculating the distance to the surface of interest from any spatial locations. Our method supports several data types and distance metrics from real-world applications. We demonstrate its efficiency and scalability on state-of-the-art supercomputers using both large-scale volume datasets and surface models. We also demonstrate in-situ distance field computation on dynamic turbulent flame surfaces for a petascale combustion simulation. Our work greatly extends the usability of distance fields for demanding applications.
Very low-refractive-index optical thin films consisting of an array of SiO2 nanorods
NASA Astrophysics Data System (ADS)
Xi, J.-Q.; Kim, Jong Kyu; Schubert, E. F.; Ye, Dexian; Lu, T.-M.; Lin, Shawn-Yu; Juneja, Jasbir S.
2006-03-01
The refractive-index contrast in dielectric multilayer structures, optical resonators, and photonic crystals is an important figure of merit that creates a strong demand for high-quality thin films with a low refractive index. A SiO2 nanorod layer with low refractive index of n=1.08, to our knowledge the lowest ever reported in thin-film materials, is grown by oblique-angle electron-beam deposition of SiO2. A single-pair distributed Bragg reflector employing a SiO2 nanorod layer is demonstrated to have enhanced reflectivity, showing the great potential of low-refractive-index films for applications in photonic structures and devices.
Integrally rigidized acoustic interior spacecraft panel
NASA Technical Reports Server (NTRS)
1976-01-01
A sandwich panel concept is described which utilizes a monolithic I-beam design as the core. The core and skins are integrally bonded with thermosetting resin into a homogeneous structure. In addition to possessing a high strength to weight ratio, the panel resists combustion, delamination, aging due to fatigue, localized stresses, and exhibits good acoustic properties. Since the panel concept has definite potential as a high flame retardant and low smoke emission panel with excellent structural integrity, aerospace materials were used to optimize the construction for highly demanding space shuttle applications. The specific materials of construction were chosen for low flammability and off-gassing properties as well as for strength, light weight, and sound dampening.
Abma, Femke I; Bültmann, Ute; Amick Iii, Benjamin C; Arends, Iris; Dorland, Heleen F; Flach, Peter A; van der Klink, Jac J L; van de Ven, Hardy A; Bjørner, Jakob Bue
2017-09-09
Objective The Work Role Functioning Questionnaire v2.0 (WRFQ) is an outcome measure linking a persons' health to the ability to meet work demands in the twenty-first century. We aimed to examine the construct validity of the WRFQ in a heterogeneous set of working samples in the Netherlands with mixed clinical conditions and job types to evaluate the comparability of the scale structure. Methods Confirmatory factor and multi-group analyses were conducted in six cross-sectional working samples (total N = 2433) to evaluate and compare a five-factor model structure of the WRFQ (work scheduling demands, output demands, physical demands, mental and social demands, and flexibility demands). Model fit indices were calculated based on RMSEA ≤ 0.08 and CFI ≥ 0.95. After fitting the five-factor model, the multidimensional structure of the instrument was evaluated across samples using a second order factor model. Results The factor structure was robust across samples and a multi-group model had adequate fit (RMSEA = 0.63, CFI = 0.972). In sample specific analyses, minor modifications were necessary in three samples (final RMSEA 0.055-0.080, final CFI between 0.955 and 0.989). Applying the previous first order specifications, a second order factor model had adequate fit in all samples. Conclusion A five-factor model of the WRFQ showed consistent structural validity across samples. A second order factor model showed adequate fit, but the second order factor loadings varied across samples. Therefore subscale scores are recommended to compare across different clinical and working samples.
Application of advanced structure to multi-tone mask for FPD process
NASA Astrophysics Data System (ADS)
Song, Jin-Han; Jeong, Jin-Woong; Kim, Kyu-Sik; Jeong, Woo-Gun; Yun, Sang-Pil; Lee, Dong-Heok; Choi, Sang-Soo
2017-07-01
In accordance with improvement of FPD technology, masks such as phase shift mask (PSM) and multi-tone mask (MTM) for a particular purpose also have been developed. Above all, the MTM consisted of more than tri-tone transmittance has a substantial advantage which enables to reduce the number of mask demand in FPD fabrication process contrast to normal mask of two-tone transmittance.[1,2] A chromium (Cr)-based MTM (Typically top type) is being widely employed because of convenience of etch process caused by its only Cr-based structure consisted of Cr absorber layer and Cr half-tone layer. However, the top type of Cr-based MTM demands two Cr sputtering processes after each layer etching process and writing process. For this reason, a different material from the Cr-based MTM is required for reduction of mask fabrication time and cost. In this study, we evaluate a MTM which has a structure combined Cr with molybdenum silicide (MoSi) to resolve the issues mentioned above. The MoSi which is demonstrated by integrated circuit (IC) process is a suitable material for MTM evaluation. This structure could realize multi-transmittance in common with the Cr-based MTM. Moreover, it enables to reduce the number of sputtering process. We investigate a optimized structure upon consideration of productivity along with performance such as critical dimension (CD) variation and transmittance range of each structure. The transmittance is targeted at h-line wavelength (405 nm) in the evaluation. Compared with Cr-based MTM, the performances of all Cr-/MoSi-based MTMs are considered.
U.S. Heat Demand by Sector for Potential Application of Direct Use Geothermal
Katherine Young
2016-06-23
This dataset includes heat demand for potential application of direct use geothermal broken down into 4 sectors: agricultural, commercial, manufacturing and residential. The data for each sector are organized by county, were disaggregated specifically to assess the market demand for geothermal direct use, and were derived using methodologies customized for each sector based on the availability of data and other sector-specific factors. This dataset also includes a paper containing a full explanation of the methodologies used.
Laser applications in advanced chip packaging
NASA Astrophysics Data System (ADS)
Müller, Dirk; Held, Andrew; Pätzel, Rainer; Clark, Dave; van Nunen, Joris
2016-03-01
While applications such as drilling μ-vias and laser direct imaging have been well established in the electronics industry, the mobile device industry's push for miniaturization is generating new demands for packaging technologies that allow for further reduction in feature size while reducing manufacturing cost. CO lasers have recently become available and their shorter wavelength allows for a smaller focus and drilling hole diameters down to 25μm whilst keeping the cost similar to CO2 lasers. Similarly, nanosecond UV lasers have gained significantly in power, become more reliable and lower in cost. On a separate front, the cost of ownership reduction for Excimer lasers has made this class of lasers attractive for structuring redistribution layers of IC substrates with feature sizes down to 2μm. Improvements in reliability and lower up-front cost for picosecond lasers is enabling applications that previously were only cost effective with mechanical means or long-pulsed lasers. We can now span the gamut from 100μm to 2μm for via drilling and can cost effectively structure redistribution layers with lasers instead of UV lamps or singulate packages with picosecond lasers.
A Simultaneous Equation Demand Model for Block Rates
NASA Astrophysics Data System (ADS)
Agthe, Donald E.; Billings, R. Bruce; Dobra, John L.; Raffiee, Kambiz
1986-01-01
This paper examines the problem of simultaneous-equations bias in estimation of the water demand function under an increasing block rate structure. The Hausman specification test is used to detect the presence of simultaneous-equations bias arising from correlation of the price measures with the regression error term in the results of a previously published study of water demand in Tucson, Arizona. An alternative simultaneous equation model is proposed for estimating the elasticity of demand in the presence of block rate pricing structures and availability of service charges. This model is used to reestimate the price and rate premium elasticities of demand in Tucson, Arizona for both the usual long-run static model and for a simple short-run demand model. The results from these simultaneous equation models are consistent with a priori expectations and are unbiased.
DOT National Transportation Integrated Search
2016-07-01
The Virginia Tech Transportation Institute (VTTI) has developed an on-demand roadway lighting : system and has tested the systems effect on driver visual performance. On-demand roadway : lighting can dramatically reduce energy usage while maintain...
Characterizing U.S. Heat Demand Market for Potential Application of Geothermal Direct Use
DOE Office of Scientific and Technical Information (OSTI.GOV)
McCabe, Kevin; Gleason, Michael; Reber, Tim
In this paper, we assess the U.S. demand for low-temperature thermal energy at the county resolution for four major end-use sectors: residential buildings, commercial buildings, manufacturing facilities, and agricultural facilities. Existing, publicly available data on the U.S. thermal demand market are characterized by coarse spatial resolution, with assessments typically at the state-level or larger. For many uses, these data are sufficient; however, our research was motivated by an interest in assessing the potential demand for direct use (DU) of low-temperature (30 degrees to 150 degrees C) geothermal heat. The availability and quality of geothermal resources for DU applications are highlymore » spatially heterogeneous; therefore, to assess the potential market for these resources, it is necessary to understand the spatial variation in demand for low-temperature resources at a local resolution. This paper presents the datasets and methods we used to develop county-level estimates of the thermal demand for the residential, commercial, manufacturing, and agricultural sectors. Although this analysis was motivated by an interest in geothermal energy deployment, the results are likely to have broader applications throughout the energy industry. The county-resolution thermal demand data developed in this study for four major U.S. sectors may have far-reaching implications for building technologies, industrial processes, and various distributed renewable energy thermal resources (e.g. biomass, solar).« less
Characterizing U.S. Heat Demand for Potential Application of Geothermal Direct Use: Preprint
DOE Office of Scientific and Technical Information (OSTI.GOV)
McCabe, Kevin; Gleason, Michael; Reber, Tim
In this paper, we assess the U.S. demand for low-temperature thermal energy at the county resolution for four major end-use sectors: residential buildings, commercial buildings, manufacturing facilities, and agricultural facilities. Existing, publicly available data on the U.S. thermal demand market are characterized by coarse spatial resolution, with assessments typically at the state-level or larger. For many uses, these data are sufficient; however, our research was motivated by an interest in assessing the potential demand for direct use (DU) of low-temperature (30 degrees to 150 degrees C) geothermal heat. The availability and quality of geothermal resources for DU applications are highlymore » spatially heterogeneous; therefore, to assess the potential market for these resources, it is necessary to understand the spatial variation in demand for low-temperature resources at a local resolution. This paper presents the datasets and methods we used to develop county-level estimates of the thermal demand for the residential, commercial, manufacturing, and agricultural sectors. Although this analysis was motivated by an interest in geothermal energy deployment, the results are likely to have broader applications throughout the energy industry. The county-resolution thermal demand data developed in this study for four major U.S. sectors may have far-reaching implications for building technologies, industrial processes, and various distributed renewable energy thermal resources (e.g. biomass, solar).« less
New perspectives on potential hydrogen storage materials using high pressure.
Song, Yang
2013-09-21
In addressing the global demand for clean and renewable energy, hydrogen stands out as the most suitable candidate for many fuel applications that require practical and efficient storage of hydrogen. Supplementary to the traditional hydrogen storage methods and materials, the high-pressure technique has emerged as a novel and unique approach to developing new potential hydrogen storage materials. Static compression of materials may result in significant changes in the structures, properties and performance that are important for hydrogen storage applications, and often lead to the formation of unprecedented phases or complexes that have profound implications for hydrogen storage. In this perspective article, 22 types of representative potential hydrogen storage materials that belong to four major classes--simple hydride, complex hydride, chemical hydride and hydrogen containing materials--were reviewed. In particular, their structures, stabilities, and pressure-induced transformations, which were reported in recent experimental works together with supporting theoretical studies, were provided. The important contextual aspects pertinent to hydrogen storage associated with novel structures and transitions were discussed. Finally, the summary of the recent advances reviewed and the insight into the future research in this direction were given.
A general way for quantitative magnetic measurement by transmitted electrons
NASA Astrophysics Data System (ADS)
Song, Dongsheng; Li, Gen; Cai, Jianwang; Zhu, Jing
2016-01-01
EMCD (electron magnetic circular dichroism) technique opens a new door to explore magnetic properties by transmitted electrons. The recently developed site-specific EMCD technique makes it possible to obtain rich magnetic information from the Fe atoms sited at nonequivalent crystallographic planes in NiFe2O4, however it is based on a critical demand for the crystallographic structure of the testing sample. Here, we have further improved and tested the method for quantitative site-specific magnetic measurement applicable for more complex crystallographic structure by using the effective dynamical diffraction effects (general routine for selecting proper diffraction conditions, making use of the asymmetry of dynamical diffraction for design of experimental geometry and quantitative measurement, etc), and taken yttrium iron garnet (Y3Fe5O12, YIG) with more complex crystallographic structure as an example to demonstrate its applicability. As a result, the intrinsic magnetic circular dichroism signals, spin and orbital magnetic moment of iron with site-specific are quantitatively determined. The method will further promote the development of quantitative magnetic measurement with high spatial resolution by transmitted electrons.
Pulsed Eddy Current Sensing for Critical Pipe Condition Assessment.
Ulapane, Nalika; Alempijevic, Alen; Vidal Calleja, Teresa; Valls Miro, Jaime
2017-09-26
Pulsed Eddy Current (PEC) sensing is used for Non-Destructive Evaluation (NDE) of the structural integrity of metallic structures in the aircraft, railway, oil and gas sectors. Urban water utilities also have extensive large ferromagnetic structures in the form of critical pressure pipe systems made of grey cast iron, ductile cast iron and mild steel. The associated material properties render NDE of these pipes by means of electromagnetic sensing a necessity. In recent years PEC sensing has established itself as a state-of-the-art NDE technique in the critical water pipe sector. This paper presents advancements to PEC inspection in view of the specific information demanded from water utilities along with the challenges encountered in this sector. Operating principles of the sensor architecture suitable for application on critical pipes are presented with the associated sensor design and calibration strategy. A Gaussian process-based approach is applied to model a functional relationship between a PEC signal feature and critical pipe wall thickness. A case study demonstrates the sensor's behaviour on a grey cast iron pipe and discusses the implications of the observed results and challenges relating to this application.
Chemically Active, Porous 3D-Printed Thermoplastic Composites
DOE Office of Scientific and Technical Information (OSTI.GOV)
Evans, Kent A.; Kennedy, Zachary C.; Arey, Bruce W.
Metal-organic frameworks (MOFs) exhibit exceptional properties and are widely investigated because of their structural and functional versatility relevant to catalysis, separations, and sensing applications. However, their commercial or large-scale application is often limited by their powder forms. To address this, we report the production of MOF-thermoplastic polymer composites accessed via a standard 3D printer. MOFs (Zeolitic imidazolate framework; ZIF-8) were successfully incorporated homogeneously into both poly(lactic acid) (PLA) and thermoplastic polyurethane (TPU) matrices, extruded into filaments, and utilized for on-demand access to 3D structures by fused-deposition modeling. Printed rigid PLA-MOF composites displayed good structural integrity, high surface area ((SA)avg =more » 531 m2 g-1) and hierarchical pore features. Flexible TPU-MOF composites (SAavg = 706 m2 g-1) were achieved by employing a sacrificial fluoropolymer readily removed post-printing. Critically, embedded particles in the plastic matrices retain their ability to participate in chemical interactions characteristic of the parent MOF. The fabrication strategies can be extended to other MOFs and illustrate the potential of 3D printing to create unique porous and high surface area chemically-active structures.« less
What is the Impact of Utility Demand Charges on a DCFC host
DOE Office of Scientific and Technical Information (OSTI.GOV)
Francfort, James Edward
The PEV Electric Vehicle Supply Equipment (EVSE) delivered by The EV Project included both AC Level 2 and DCFC units. Over 100 of these dual-port Blink DC fast chargers were deployed by The EV Project. These DCFCs were installed in workplaces and in publicly accessible locations near traffic hubs, retail centers, parking lots, restaurants, and similar locations. The Blink DCFC is capable of charging at power up to 60 kW. Its dual-port design sequences the charge from one port to the other, delivering power to only one of two vehicles connected at a time. The actual power delivered through amore » port is determined by the PEV’s on-board battery management system (BMS). Both the power and the total energy used to recharge a PEV can represent a significant cost for the charging site host. Many electric utilities impose fees for power demand as part of their commercial rate structure. The demand charge incurred by a customer is related to the peak power used during a monthly billing cycle. This is in contrast to the cumulative total energy usage that is the more familiar utility charge seen for most residential services. A demand charge is typically assessed for the highest average power over any 15 minute interval during the monthly billing cycle. One objective of The EV Project was to identify and elucidate the motivations and barriers to potential DCFC site hosts. The application of electric utility demand charges is one such potential barrier. This subject was introduced in the paper: DC Fast Charge - Demand Charge Reduction1. It discussed demand charge impact in general terms in order to focus on potential mitigation actions. This paper identifies specific cases in order to quantify the impact of demand charges on EV Project DCFC hosts.« less
Models for forecasting energy use in the US farm sector
NASA Astrophysics Data System (ADS)
Christensen, L. R.
1981-07-01
Econometric models were developed and estimated for the purpose of forecasting electricity and petroleum demand in US agriculture. A structural approach is pursued which takes account of the fact that the quantity demanded of any one input is a decision made in conjunction with other input decisions. Three different functional forms of varying degrees of complexity are specified for the structural cost function, which describes the cost of production as a function of the level of output and factor prices. Demand for materials (all purchased inputs) is derived from these models. A separate model which break this demand up into demand for the four components of materials is used to produce forecasts of electricity and petroleum is a stepwise manner.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Deka, Deepjyoti; Backhaus, Scott N.; Chertkov, Michael
Limited placement of real-time monitoring devices in the distribution grid, recent trends notwithstanding, has prevented the easy implementation of demand-response and other smart grid applications. Part I of this paper discusses the problem of learning the operational structure of the grid from nodal voltage measurements. In this work (Part II), the learning of the operational radial structure is coupled with the problem of estimating nodal consumption statistics and inferring the line parameters in the grid. Based on a Linear-Coupled(LC) approximation of AC power flows equations, polynomial time algorithms are designed to identify the structure and estimate nodal load characteristics and/ormore » line parameters in the grid using the available nodal voltage measurements. Then the structure learning algorithm is extended to cases with missing data, where available observations are limited to a fraction of the grid nodes. The efficacy of the presented algorithms are demonstrated through simulations on several distribution test cases.« less
Finite element simulation of adaptive aerospace structures with SMA actuators
NASA Astrophysics Data System (ADS)
Frautschi, Jason; Seelecke, Stefan
2003-07-01
The particular demands of aerospace engineering have spawned many of the developments in the field of adaptive structures. Shape memory alloys are particularly attractive as actuators in these types of structures due to their large strains, high specific work output and potential for structural integration. However, the requisite extensive physical testing has slowed development of potential applications and highlighted the need for a simulation tool for feasibility studies. In this paper we present an implementation of an extended version of the M'ller-Achenbach SMA model into a commercial finite element code suitable for such studies. Interaction between the SMA model and the solution algorithm for the global FE equations is thoroughly investigated with respect to the effect of tolerances and time step size on convergence, computational cost and accuracy. Finally, a simulation of a SMA-actuated flexible trailing edge of an aircraft wing modeled with beam elements is presented.
NASA Astrophysics Data System (ADS)
Fassbender, Christoph; Goeters, Klaus-Martin
European participation in the Space Station Freedom brought about new challenges for the psychological selection of astronaut candidates, particularly in respect to specific demands of long duration space flights. For this reason existing selection criteria and methods were reassessed. On these grounds a study was undertaken applying a unique composition of aptitude tests to a group of 97 ESA scientists and engineers who are highly comparable to the expected astronaut applicants with respect to age and education. The tests assessed operational aptitudes such as logical reasoning, memory function, perception, spatial orientation, attention, psychomotor function, and multiple task capacity. The study goals were: 1) Verification of psychometric qualities and applicability of tests in a normative group; 2) Search for culture-fair tests by which multi-national groups can be examined; 3) Identification of test methods which consider general and special operational demands of long duration space flights. Based on the empirical findings a test battery was arranged for use in the selection of ESA astronaut applicants. Results showed that 16 out of the 18 employed tests have good psychometric qualities and differentiate reliably in the special group of testees. The meta structure of the test battery as described by a factorial analysis is presented. Applicability of tests was generally high. Tests were culture-fair, however, a relation between English language skills and test results was identified. Since most item material was language-free, this was explained with the importance of English language skills for the understanding of test instructions. Solutions to this effect are suggested.
NASA Astrophysics Data System (ADS)
Zhai, Zirui; Wang, Yong; Jiang, Hanqing
2018-03-01
Origami has been employed to build deployable mechanical metamaterials through folding and unfolding along the crease lines. Deployable metamaterials are usually flexible, particularly along their deploying and collapsing directions, which unfortunately in many cases leads to an unstable deployed state, i.e., small perturbations may collapse the structure along the same deployment path. Here we create an origami-inspired mechanical metamaterial with on-demand deployability and selective collapsibility through energy analysis. This metamaterial has autonomous deployability from the collapsed state and can be selectively collapsed along two different paths, embodying low stiffness for one path and substantially high stiffness for another path. The created mechanical metamaterial yields load-bearing capability in the deployed direction while possessing great deployability and collapsibility. The principle in this work can be utilized to design and create versatile origami-inspired mechanical metamaterials that can find many applications.
Allograft replacement for absent native tissue.
Chaudhury, Salma; Wanivenhaus, Florian; Fox, Alice J; Warren, Russell F; Doyle, Maureen; Rodeo, Scott A
2013-03-01
Structural instability due to poor soft tissue quality often requires augmentation. Allografts are important biological substitutes that are used for the symptomatic patient in the reconstruction of deficient ligaments, tendons, menisci, and osteochondral defects. Interest in the clinical application of allografts has arisen from the demand to obtain stable anatomy with restoration of function and protection against additional injury, particularly for high-demand patients who participate in sports. Traditionally, allografts were employed to reinforce weakened tissue. However, they can also be employed to substitute deficient or functionally absent tissue, particularly in the sports medicine setting. This article presents a series of 6 cases that utilized allografts to restore functionally deficient anatomic architecture, rather than just simply augmenting the degenerated or damaged native tissue. Detailed discussions are presented of the use of allografts as a successful treatment strategy to replace functionally weakened tissue, often after failed primary repairs.
Allograft Replacement for Absent Native Tissue
Chaudhury, Salma; Wanivenhaus, Florian; Fox, Alice J.; Warren, Russell F.; Doyle, Maureen; Rodeo, Scott A.
2013-01-01
Context: Structural instability due to poor soft tissue quality often requires augmentation. Allografts are important biological substitutes that are used for the symptomatic patient in the reconstruction of deficient ligaments, tendons, menisci, and osteochondral defects. Interest in the clinical application of allografts has arisen from the demand to obtain stable anatomy with restoration of function and protection against additional injury, particularly for high-demand patients who participate in sports. Traditionally, allografts were employed to reinforce weakened tissue. However, they can also be employed to substitute deficient or functionally absent tissue, particularly in the sports medicine setting. Objective: This article presents a series of 6 cases that utilized allografts to restore functionally deficient anatomic architecture, rather than just simply augmenting the degenerated or damaged native tissue. Detailed discussions are presented of the use of allografts as a successful treatment strategy to replace functionally weakened tissue, often after failed primary repairs. PMID:24427387
Configuration complexity assessment of convergent supply chain systems
NASA Astrophysics Data System (ADS)
Modrak, Vladimir; Marton, David
2014-07-01
System designers usually generate alternative configurations of supply chains (SCs) by varying especially fixed assets to satisfy a desired production scope and rate. Such alternatives often vary in associated costs and other facets including degrees of complexity. Hence, a measure of configuration complexity can be a tool for comparison and decision-making. This paper presents three approaches to assessment of configuration complexity and their applications to designing convergent SC systems. Presented approaches are conceptually distinct ways of measuring structural complexity parameters based on different preconditions and circumstances of assembly systems which are typical representatives of convergent SCs. There are applied two similar approaches based on different preconditions that are related to demand shares. Third approach does not consider any special condition relating to character of final product demand. Subsequently, we propose a framework for modeling of assembly SC models, which are dividing to classes.
Rate Analysis of Two Photovoltaic Systems in San Diego
DOE Office of Scientific and Technical Information (OSTI.GOV)
Doris, E.; Ong, S.; Van Geet, O.
2009-07-01
Analysts have found increasing evidence that rate structure has impacts on the economics of solar systems. This paper uses 2007 15-minute interval photovoltaic (PV) system and load data from two San Diego City water treatment facilities to illustrate impacts of different rate designs. The comparison is based on rates available in San Diego at the time of data collection and include proportionately small to large demand charges (relative to volumetric consumption), and varying on- and off- peak times. Findings are twofold for these large commercial systems: 1) transferring costs into demand charges does not result in savings and 2) changesmore » in peak times do not result in a major cost difference during the course of a year. While lessons learned and discussion on rate components are based on the findings, the applicability is limited to buildings with similar systems, environments, rate options, and loads.« less
Zhai, Zirui; Wang, Yong; Jiang, Hanqing
2018-02-27
Origami has been employed to build deployable mechanical metamaterials through folding and unfolding along the crease lines. Deployable metamaterials are usually flexible, particularly along their deploying and collapsing directions, which unfortunately in many cases leads to an unstable deployed state, i.e., small perturbations may collapse the structure along the same deployment path. Here we create an origami-inspired mechanical metamaterial with on-demand deployability and selective collapsibility through energy analysis. This metamaterial has autonomous deployability from the collapsed state and can be selectively collapsed along two different paths, embodying low stiffness for one path and substantially high stiffness for another path. The created mechanical metamaterial yields load-bearing capability in the deployed direction while possessing great deployability and collapsibility. The principle in this work can be utilized to design and create versatile origami-inspired mechanical metamaterials that can find many applications. Copyright © 2018 the Author(s). Published by PNAS.
Zhai, Zirui; Wang, Yong
2018-01-01
Origami has been employed to build deployable mechanical metamaterials through folding and unfolding along the crease lines. Deployable metamaterials are usually flexible, particularly along their deploying and collapsing directions, which unfortunately in many cases leads to an unstable deployed state, i.e., small perturbations may collapse the structure along the same deployment path. Here we create an origami-inspired mechanical metamaterial with on-demand deployability and selective collapsibility through energy analysis. This metamaterial has autonomous deployability from the collapsed state and can be selectively collapsed along two different paths, embodying low stiffness for one path and substantially high stiffness for another path. The created mechanical metamaterial yields load-bearing capability in the deployed direction while possessing great deployability and collapsibility. The principle in this work can be utilized to design and create versatile origami-inspired mechanical metamaterials that can find many applications. PMID:29440441
NASA Technical Reports Server (NTRS)
Hammond, Monica S.; Good, James E.; Gilley, Scott D.; Howard, Richard W.
2006-01-01
NASA's human exploration initiative poses great opportunity and risk for manned and robotic missions to the Moon, Mars, and beyond. Engineers and scientists at the Marshall Space Flight Center (MSFC) are developing technologies for in situ fabrication capabilities during lunar and Martian surface operations utilizing provisioned and locally refined materials. Current fabrication technologies must be advanced to support the special demands and applications of the space exploration initiative such as power, weight and volume constraints. In Situ Fabrication and Repair (ISFR) will advance state-of-the-art technologies in support of habitat structure development, tools, and mechanical part fabrication. The repair and replacement of space mission components, such as life support items or crew exercise equipment, fall within the ISFR scope. This paper will address current fabrication technologies relative to meeting ISFR targeted capabilities, near-term advancement goals, and systematic evaluation of various fabrication methods.
Si, Liang; Baier, Horst
2015-07-08
For the future design of smart aerospace structures, the development and application of a reliable, real-time and automatic monitoring and diagnostic technique is essential. Thus, with distributed sensor networks, a real-time automatic structural health monitoring (SHM) technique is designed and investigated to monitor and predict the locations and force magnitudes of unforeseen foreign impacts on composite structures and to estimate in real time mode the structural state when impacts occur. The proposed smart impact visualization inspection (IVI) technique mainly consists of five functional modules, which are the signal data preprocessing (SDP), the forward model generator (FMG), the impact positioning calculator (IPC), the inverse model operator (IMO) and structural state estimator (SSE). With regard to the verification of the practicality of the proposed IVI technique, various structure configurations are considered, which are a normal CFRP panel and another CFRP panel with "orange peel" surfaces and a cutout hole. Additionally, since robustness against several background disturbances is also an essential criterion for practical engineering demands, investigations and experimental tests are carried out under random vibration interfering noise (RVIN) conditions. The accuracy of the predictions for unknown impact events on composite structures using the IVI technique is validated under various structure configurations and under changing environmental conditions. The evaluated errors all fall well within a satisfactory limit range. Furthermore, it is concluded that the IVI technique is applicable for impact monitoring, diagnosis and assessment of aerospace composite structures in complex practical engineering environments.
Real-Time Impact Visualization Inspection of Aerospace Composite Structures with Distributed Sensors
Si, Liang; Baier, Horst
2015-01-01
For the future design of smart aerospace structures, the development and application of a reliable, real-time and automatic monitoring and diagnostic technique is essential. Thus, with distributed sensor networks, a real-time automatic structural health monitoring (SHM) technique is designed and investigated to monitor and predict the locations and force magnitudes of unforeseen foreign impacts on composite structures and to estimate in real time mode the structural state when impacts occur. The proposed smart impact visualization inspection (IVI) technique mainly consists of five functional modules, which are the signal data preprocessing (SDP), the forward model generator (FMG), the impact positioning calculator (IPC), the inverse model operator (IMO) and structural state estimator (SSE). With regard to the verification of the practicality of the proposed IVI technique, various structure configurations are considered, which are a normal CFRP panel and another CFRP panel with “orange peel” surfaces and a cutout hole. Additionally, since robustness against several background disturbances is also an essential criterion for practical engineering demands, investigations and experimental tests are carried out under random vibration interfering noise (RVIN) conditions. The accuracy of the predictions for unknown impact events on composite structures using the IVI technique is validated under various structure configurations and under changing environmental conditions. The evaluated errors all fall well within a satisfactory limit range. Furthermore, it is concluded that the IVI technique is applicable for impact monitoring, diagnosis and assessment of aerospace composite structures in complex practical engineering environments. PMID:26184196
Epifluorescent direct-write photolithography for microfluidic applications
NASA Astrophysics Data System (ADS)
Higgins, MacCallister; Geiger, Emil J.
2015-01-01
We present a technique for fabricating soft-lithography molds created using an epifluorescent microscope. By focusing the UV light emitted from a Hg arc lamp, we demonstrate the ability to direct-write photoresist features with a minimum resolution of 45 μm. This resolution is satisfactory for many microfluidic applications. A major advantage of this technique is its low cost, both in terms of capital investment and on-going expenditures. Furthermore, by using a motorized stage, we can quickly fabricate a design on demand, eliminating the need, cost, and lead-time required for a photomask. With the addition of an electronic shutter, complicated separate structures can be imaged and utilized to make a wide range of microfluidic devices. We demonstrate this technique using dry-film resist due to its low cost, ease of application, and less stringent safety protocols.
Jiang, Qian; Zeng, Wenxia; Zhang, Canying; Meng, Zhaoguo; Wu, Jiawei; Zhu, Qunzhi; Wu, Daxiong; Zhu, Haitao
2017-12-19
Photothermal conversion materials have promising applications in many fields and therefore they have attracted tremendous attention. However, the multi-functionalization of a single nanostructure to meet the requirements of multiple photothermal applications is still a challenge. The difficulty is that most nanostructures have specific absoprtion band and are not flexible to different demands. In the current work, we reported the synthesis and multi-band photothermal conversion of Ag@Ag 2 S core@shell structures with gradually varying shell thickness. We synthesized the core@shell structures through the sulfidation of Ag nanocubes by taking the advantage of their spatially different reactivity. The resulting core@shell structures show an octopod-like mopgorlogy with a Ag 2 S bulge sitting at each corner of the Ag nanocubes. The thickness of the Ag 2 S shell gradually increases from the central surface towards the corners of the structure. The synthesized core@shell structures show a broad band absorption spectrum from 300 to 1100 nm. Enhanced photothermal conversion effect is observed under the illuminations of 635, 808, and 1064 nm lasers. The results indicate that the octopod-like Ag@Ag 2 S core@shell structures have characteristics of multi-band photothermal conversion. The current work might provide a guidance for the design and synthesis of multifunctional photothermal conversion materials.
48 CFR 32.604 - Demand for payment.
Code of Federal Regulations, 2012 CFR
2012-10-01
... provided in Section 611 of the Contract Disputes Act of 1978 (Public Law 95-563), which is applicable to the period in which the amount becomes due, and then at the rate applicable for each six-month period..., the contracting officer should not issue a demand for payment if the contracting officer only becomes...
48 CFR 32.604 - Demand for payment.
Code of Federal Regulations, 2013 CFR
2013-10-01
... provided in Section 611 of the Contract Disputes Act of 1978 (Public Law 95-563), which is applicable to the period in which the amount becomes due, and then at the rate applicable for each six-month period..., the contracting officer should not issue a demand for payment if the contracting officer only becomes...
48 CFR 32.604 - Demand for payment.
Code of Federal Regulations, 2011 CFR
2011-10-01
... provided in Section 611 of the Contract Disputes Act of 1978 (Public Law 95-563), which is applicable to the period in which the amount becomes due, and then at the rate applicable for each six-month period..., the contracting officer should not issue a demand for payment if the contracting officer only becomes...
Mobile Learning Application Interfaces: First Steps to a Cognitive Load Aware System
ERIC Educational Resources Information Center
Deegan, Robin
2013-01-01
Mobile learning is a cognitively demanding application and more frequently the ubiquitous nature of mobile computing means that mobile devices are used in cognitively demanding environments. This paper examines the nature of this use of mobile devices from a Learning, Usability and Cognitive Load Theory perspective. It suggests scenarios where…
DOT National Transportation Integrated Search
2017-04-01
The primary objective of this project is to develop multiple simulation testbeds and transportation models to evaluate the impacts of Connected Vehicle Dynamic Mobility Applications (DMA) and Active Transportation and Demand Management (ATDM) strateg...
DOT National Transportation Integrated Search
2017-04-01
The primary objective of this project is to develop multiple simulation testbeds and transportation models to evaluate the impacts of Connected Vehicle Dynamic Mobility Applications (DMA) and Active Transportation and Demand Management (ATDM) strateg...
What Drives University Applications? An Attempt to Explain Aggregate Demand for Higher Education
ERIC Educational Resources Information Center
Vieira, Carlos; Vieira, Isabel
2014-01-01
Low educational attainment is frequently pointed out as a barrier to social and economic development and most governments aim at increasing participation in higher education. However, effective strategies to increase aggregate demand require information on its most relevant determinants, which is difficult to obtain because applications to higher…
DOT National Transportation Integrated Search
2017-07-16
The primary objective of this project is to develop multiple simulation testbeds/transportation models to evaluate the impacts of Dynamic Mobility Applications (DMA) and the Active Transportation and Demand Management (ATDM) strategies. Specifically,...
DOT National Transportation Integrated Search
2017-03-01
The primary objective of this project is to develop multiple simulation testbeds/transportation models to evaluate the impacts of DMA connected vehicle applications and the active transportation and demand management (ATDM) strategies. The primary pu...
The impact of job and family demands on partner's fatigue: A study of Japanese dual-earner parents.
Watanabe, Mayumi; Shimazu, Akihito; Bakker, Arnold B; Demerouti, Evangelia; Shimada, Kyoko; Kawakami, Norito
2017-01-01
This study of Japanese dual-earner couples examined the impact of family and job demands on one's own and one's partner's fatigue as well as gender differences in these effects. A total of 2,502 parents (1,251 couples) were surveyed using a self-administered questionnaire. A crossover model was tested using structural equation modeling. The results of structural equation modeling analyses showed that both job and family demands independently exacerbated fatigue. There was an indirect effect of job and family demands on partner fatigue through one's own fatigue only from husbands to wives. An indirect effect of job demands on partner fatigue through partner's family demands was identified only from wives to husbands. Furthermore, there were gender differences in the crossover of fatigue. This study shows that job and family demands influence family circumstances. When considering means to reduce employees' fatigue, gender differences in the mechanism of fatigue need to be taken into account.
NASA Astrophysics Data System (ADS)
Singh, Krishna P.; Baweja, Lokesh; Wolkenhauer, Olaf; Rahman, Qamar; Gupta, Shailendra K.
2018-03-01
Graphene-based nanomaterials (GBNMs) are widely used in various industrial and biomedical applications. GBNMs of different compositions, size and shapes are being introduced without thorough toxicity evaluation due to the unavailability of regulatory guidelines. Computational toxicity prediction methods are used by regulatory bodies to quickly assess health hazards caused by newer materials. Due to increasing demand of GBNMs in various size and functional groups in industrial and consumer based applications, rapid and reliable computational toxicity assessment methods are urgently needed. In the present work, we investigate the impact of graphene and graphene oxide nanomaterials on the structural conformations of small hepcidin peptide and compare the materials for their structural and conformational changes. Our molecular dynamics simulation studies revealed conformational changes in hepcidin due to its interaction with GBMNs, which results in a loss of its functional properties. Our results indicate that hepcidin peptide undergo severe structural deformations when superimposed on the graphene sheet in comparison to graphene oxide sheet. These observations suggest that graphene is more toxic than a graphene oxide nanosheet of similar area. Overall, this study indicates that computational methods based on structural deformation, using molecular dynamics (MD) simulations, can be used for the early evaluation of toxicity potential of novel nanomaterials.
Stiffness degradation-based damage model for RC members and structures using fiber-beam elements
NASA Astrophysics Data System (ADS)
Guo, Zongming; Zhang, Yaoting; Lu, Jiezhi; Fan, Jian
2016-12-01
To meet the demand for an accurate and highly efficient damage model with a distinct physical meaning for performance-based earthquake engineering applications, a stiffness degradation-based damage model for reinforced concrete (RC) members and structures was developed using fiber beam-column elements. In this model, damage indices for concrete and steel fibers were defined by the degradation of the initial reloading modulus and the low-cycle fatigue law. Then, section, member, story and structure damage was evaluated by the degradation of the sectional bending stiffness, rod-end bending stiffness, story lateral stiffness and structure lateral stiffness, respectively. The damage model was realized in Matlab by reading in the outputs of OpenSees. The application of the damage model to RC columns and a RC frame indicates that the damage model is capable of accurately predicting the magnitude, position, and evolutionary process of damage, and estimating story damage more precisely than inter-story drift. Additionally, the damage model establishes a close connection between damage indices at various levels without introducing weighting coefficients or force-displacement relationships. The development of the model has perfected the damage assessment function of OpenSees, laying a solid foundation for damage estimation at various levels of a large-scale structure subjected to seismic loading.
A novel approach to enhance the accuracy of vibration control of Frames
NASA Astrophysics Data System (ADS)
Toloue, Iraj; Shahir Liew, Mohd; Harahap, I. S. H.; Lee, H. E.
2018-03-01
All structures built within known seismically active regions are typically designed to endure earthquake forces. Despite advances in earthquake resistant structures, it can be inferred from hindsight that no structure is entirely immune to damage from earthquakes. Active vibration control systems, unlike the traditional methods which enlarge beams and columns, are highly effective countermeasures to reduce the effects of earthquake loading on a structure. It requires fast computation of nonlinear structural analysis in near time and has historically demanded advanced programming hosted on powerful computers. This research aims to develop a new approach for active vibration control of frames, which is applicable over both elastic and plastic material behavior. In this study, the Force Analogy Method (FAM), which is based on Hook's Law is further extended using the Timoshenko element which considers shear deformations to increase the reliability and accuracy of the controller. The proposed algorithm is applied to a 2D portal frame equipped with linear actuator, which is designed based on full state Linear Quadratic Regulator (LQR). For comparison purposes, the portal frame is analysed by both the Euler Bernoulli and Timoshenko element respectively. The results clearly demonstrate the superiority of the Timoshenko element over Euler Bernoulli for application in nonlinear analysis.
A study of mechanical properties for aluminum GMA weldments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kluken, A.O.; Bjoerneklett, B.
1997-02-01
Medium- to high-strength aluminum alloys represent an attractive alternative to steel as a material for critical structural members. One area of great interest for their use is the transportation industry due to the increasing demands for less environmental impact through improved fuel efficiency, weight reductions, and increased load capacity. Fabrication of structural bodies involves, in most instances, the application of a joining process. Load-carrying members must be joined together or nonload-carrying parts attached to the primary structure. Although adhesive bonding, laser beam welding and friction stir welding are attractive processes for joining of aluminum, gas metal arc welding (GMAW) ismore » by far the most widely used process at present. Fusion welding of a heat-treatable aluminum alloy represents an additional local heat treatment of material that previously has been processed through tight temperature control to obtain the desired mechanical properties. Hence, great attention must be given to selection of alloy and temper condition, welding parameters, and postweld aging procedures for a given application. The objective of this investigation was to establish mechanical property data, i.e., tensile strength and impact toughness, for Al-Mg-Si and Al-Zn-Mg gas metal arc weldments applicable to the automotive and shipbuilding industries.« less
NASA Astrophysics Data System (ADS)
Fan, Peixun; Wu, Hui; Zhong, Minlin; Zhang, Hongjun; Bai, Benfeng; Jin, Guofan
2016-07-01
Efficient solar energy harvesting and photothermal conversion have essential importance for many practical applications. Here, we present a laser-induced cauliflower-shaped hierarchical surface nanostructure on a copper surface, which exhibits extremely high omnidirectional absorption efficiency over a broad electromagnetic spectral range from the UV to the near-infrared region. The measured average hemispherical absorptance is as high as 98% within the wavelength range of 200-800 nm, and the angle dependent specular reflectance stays below 0.1% within the 0-60° incident angle. Such a structured copper surface can exhibit an apparent heating up effect under the sunlight illumination. In the experiment of evaporating water, the structured surface yields an overall photothermal conversion efficiency over 60% under an illuminating solar power density of ~1 kW m-2. The presented technology provides a cost-effective, reliable, and simple way for realizing broadband omnidirectional light absorptive metal surfaces for efficient solar energy harvesting and utilization, which is highly demanded in various light harvesting, anti-reflection, and photothermal conversion applications. Since the structure is directly formed by femtosecond laser writing, it is quite suitable for mass production and can be easily extended to a large surface area.Efficient solar energy harvesting and photothermal conversion have essential importance for many practical applications. Here, we present a laser-induced cauliflower-shaped hierarchical surface nanostructure on a copper surface, which exhibits extremely high omnidirectional absorption efficiency over a broad electromagnetic spectral range from the UV to the near-infrared region. The measured average hemispherical absorptance is as high as 98% within the wavelength range of 200-800 nm, and the angle dependent specular reflectance stays below 0.1% within the 0-60° incident angle. Such a structured copper surface can exhibit an apparent heating up effect under the sunlight illumination. In the experiment of evaporating water, the structured surface yields an overall photothermal conversion efficiency over 60% under an illuminating solar power density of ~1 kW m-2. The presented technology provides a cost-effective, reliable, and simple way for realizing broadband omnidirectional light absorptive metal surfaces for efficient solar energy harvesting and utilization, which is highly demanded in various light harvesting, anti-reflection, and photothermal conversion applications. Since the structure is directly formed by femtosecond laser writing, it is quite suitable for mass production and can be easily extended to a large surface area. Electronic supplementary information (ESI) available: XRD patterns of the fs laser structured Cu surface as produced and after the photothermal conversion test, directly measured temperature values on Cu surfaces, temperature rise on Cu surfaces at varied solar irradiation angles, comparison of the white light and IR images of the structured Cu surface with the polished Cu surface, temperature rise on the peripheral zones of the blue coating surface. See DOI: 10.1039/c6nr03662g
Demand for resident hunting in the southeastern United States
Neelam Poudyal; Seong Hoon Cho; J. Michael Bowker
2008-01-01
We modeled hunting demand among resident hunters in the Southeastern United States. Our model revealed that future hunting demand will likely decline in this region. Population growth in the region will increase demand but structural change in the region's demography (e.g., "browning" and "aging "), along with declining forestland access will...
The effects of declining population growth on the demand for housing.
Thomas C. Marcin
1974-01-01
Declining population growth and unprecedented changes in the age structure of the population in the next several decades will profoundly affect housing demand in the next 50 years. A decline in housing demand and substantial change in the type of housing in demand are likely to occur by 1990.
Nonparametric bootstrap analysis with applications to demographic effects in demand functions.
Gozalo, P L
1997-12-01
"A new bootstrap proposal, labeled smooth conditional moment (SCM) bootstrap, is introduced for independent but not necessarily identically distributed data, where the classical bootstrap procedure fails.... A good example of the benefits of using nonparametric and bootstrap methods is the area of empirical demand analysis. In particular, we will be concerned with their application to the study of two important topics: what are the most relevant effects of household demographic variables on demand behavior, and to what extent present parametric specifications capture these effects." excerpt
Forecasting Hourly Water Demands With Seasonal Autoregressive Models for Real-Time Application
NASA Astrophysics Data System (ADS)
Chen, Jinduan; Boccelli, Dominic L.
2018-02-01
Consumer water demands are not typically measured at temporal or spatial scales adequate to support real-time decision making, and recent approaches for estimating unobserved demands using observed hydraulic measurements are generally not capable of forecasting demands and uncertainty information. While time series modeling has shown promise for representing total system demands, these models have generally not been evaluated at spatial scales appropriate for representative real-time modeling. This study investigates the use of a double-seasonal time series model to capture daily and weekly autocorrelations to both total system demands and regional aggregated demands at a scale that would capture demand variability across a distribution system. Emphasis was placed on the ability to forecast demands and quantify uncertainties with results compared to traditional time series pattern-based demand models as well as nonseasonal and single-seasonal time series models. Additional research included the implementation of an adaptive-parameter estimation scheme to update the time series model when unobserved changes occurred in the system. For two case studies, results showed that (1) for the smaller-scale aggregated water demands, the log-transformed time series model resulted in improved forecasts, (2) the double-seasonal model outperformed other models in terms of forecasting errors, and (3) the adaptive adjustment of parameters during forecasting improved the accuracy of the generated prediction intervals. These results illustrate the capabilities of time series modeling to forecast both water demands and uncertainty estimates at spatial scales commensurate for real-time modeling applications and provide a foundation for developing a real-time integrated demand-hydraulic model.
Residential water demand with endogenous pricing: The Canadian Case
NASA Astrophysics Data System (ADS)
Reynaud, Arnaud; Renzetti, Steven; Villeneuve, Michel
2005-11-01
In this paper, we show that the rate structure endogeneity may result in a misspecification of the residential water demand function. We propose to solve this endogeneity problem by estimating a probabilistic model describing how water rates are chosen by local communities. This model is estimated on a sample of Canadian local communities. We first show that the pricing structure choice reflects efficiency considerations, equity concerns, and, in some cases, a strategy of price discrimination across consumers by Canadian communities. Hence estimating the residential water demand without taking into account the pricing structures' endogeneity leads to a biased estimation of price and income elasticities. We also demonstrate that the pricing structure per se plays a significant role in influencing price responsiveness of Canadian residential consumers.
High-performing LiMgxCuyCo₁-x-yO₂ cathode material for lithium rechargeable batteries.
Nithya, Chandrasekaran; Thirunakaran, Ramasamy; Sivashanmugam, Arumugam; Gopukumar, Sukumaran
2012-08-01
Sustainable power requirements of multifarious portable electronic applications demand the development of high energy and high power density cathode materials for lithium ion batteries. This paper reports a method for rapid synthesis of a cobalt based layered cathode material doped with mixed dopants Cu and Mg. The cathode material exhibits ordered layered structure and delivers discharge capacity of ∼200 mA h g(-1) at 0.2C rate with high capacity retention of 88% over the investigated 100 cycles.
Plasticity Modelling in PM Steels
NASA Astrophysics Data System (ADS)
Andersson, M.; Angelopoulos, V.
2017-12-01
Simulations are continuously becoming more and more important to predict the behaviour of materials, components and structures. Porous materials, such as PM, put special demands on the material models used. This paper investigates the application of the Gurson material model to PM steels. It is shown how the model can be calibrated to material data. The results are also applied to an indentation test, where it's demonstrated that experimental results can be reproduced with some accuracy. Limitations of the model, and the potential to use more advanced material models are also discussed.
[Healthcare marketing elements].
Ameri, Cinzia; Fiorini, Fulvio
2014-01-01
Marketing puts its foundation on a few key concepts: need-demand, product-service, satisfaction, exchange, market, or business structure manufacturing / supply. The combination of these elements allows you to build an effective marketing strategy. Crucial in this respect is to remember the Porter matrix, which shows that for a correct analysis of the relevant market is necessary to refer to the "five forces at play", ie: customers, competitors, new entrants and substitutes threat. Another key lever for proper marketing oriented approach is the continuous and constant monitoring of the application, anticipating their dissatisfactions.
Broadband and stable acoustic vortex emitter with multi-arm coiling slits
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jiang, Xue; Liang, Bin, E-mail: liangbin@nju.edu.cn, E-mail: eleqc@nus.edu.sg, E-mail: jccheng@nju.edu.cn; Zou, Xin-ye
2016-05-16
We present the analytical design and experimental realization of a scheme based on multi-arm coiling slits to generate the stable acoustic vortices in a broadband. The proposed structure is able to spiral the acoustic wave spatially and generate the twisted acoustic vortices with invariant topological charge for a long propagation distance. Compared with conventional methods which require the electronic control of a bulky loudspeaker, this scheme provides an effective and compact solution to generate acoustic vortices with controllable topological charge in the broadband, which offers more initiatives in the demanding applications.
Gao, Fengsong; Newcombe, Peter; Tilse, Cheryl; Wilson, Jill; Tuckett, Anthony
2014-09-01
Nurse turnover in the residential aged care industry is a pressing issue. Researchers have shown ongoing interest in exploring how the factors that are amendable to change in aged care policy, regulation and funding and in organizational procedures (e.g. job demands, coping resources and psychological health of nurses) impact on turnover. However, the findings are mixed. This study tested two theoretical models of turnover to examine the structural relationships among job demands, coping resources, psychological health and turnover of residential aged care nurses. Although many previous studies operationalized turnover as intention to leave, the present study investigated actual turnover by following up with the same individuals over time, and thus provided more accurate predictive models of turnover behaviour. The sample, 239 Australian residential aged care nurses, came from the Nurses and Midwives e-cohort Study. Job demands, coping resources, and psychological health were measured using standardized instruments. Structural equation modelling was used to test the measurement and structural models. Controlling for a number of workforce and individual characteristics, coping resources (measured by job control, supervisor support, and co-worker support) were negatively and directly associated with turnover. Additionally, the findings supported the Job Demand-Control-Support model in that higher coping resources and lower job demands (indicated by psychological demands, physical demands, and effort) were related to better psychological health (measured by vitality, social functioning, role emotional, and mental health), and higher job demands were related to lower coping resources. Findings suggest that aged care policy makers and service providers might consider increasing coping resources available to nurses and minimizing job demands of care work to reduce turnover and improve nurses' psychological health. Moreover, findings from this Australian study may provide valuable practical and policy implications for other developed countries. Copyright © 2014 Elsevier Ltd. All rights reserved.
Bastani, Peivand; Mehralian, Gholamhossein; Dinarvand, Rasoul
2015-01-01
The aim of this study was to review the current methods of pharmaceutical purchasing by Iranian insurance organizations within the World Bank conceptual framework model so as to provide applicable pharmaceutical resource allocation and purchasing (RAP) arrangements in Iran. This qualitative study was conducted through a qualitative document analysis (QDA), applying the four-step Scott method in document selection, and conducting 20 semi-structured interviews using a triangulation method. Furthermore, the data were analyzed applying five steps framework analysis using Atlas-ti software. The QDA showed that the purchasers face many structural, financing, payment, delivery and service procurement and purchasing challenges. Moreover, the findings of interviews are provided in three sections including demand-side, supply-side and price and incentive regime. Localizing RAP arrangements as a World Bank Framework in a developing country like Iran considers the following as the prerequisite for implementing strategic purchasing in pharmaceutical sector: The improvement of accessibility, subsidiary mechanisms, reimbursement of new drugs, rational use, uniform pharmacopeia, best supplier selection, reduction of induced demand and moral hazard, payment reform. It is obvious that for Iran, these customized aspects are more various and detailed than those proposed in a World Bank model for developing countries.
Recent advances in design and fabrication of on-chip micro-supercapacitors
NASA Astrophysics Data System (ADS)
Beidaghi, Majid; Wang, Chunlei
2012-06-01
Recent development in miniaturized electronic devices has increased the demand for power sources that are sufficiently compact and can potentially be integrated on a chip with other electronic components. Miniaturized electrochemical capacitors (EC) or micro-supercapacitors have great potential to complement or replace batteries and electrolytic capacitors in a variety of applications. Recently, we have developed several types of micro-supercapacitors with different structural designs and active materials. Carbon-Microelectromechanical Systems (C-MEMS) with three dimensional (3D) interdigital structures are employed both as electrode material for electric double layer capacitor (EDLC) or as three dimensional (3D) current collectors of pseudo-capacitive materials. More recently, we have also developed microsupercapacitor based on hybrid graphene and carbon nanotube interdigital structures. In this paper, the recent advances in design and fabrication of on-chip micro-supercapacitors are reviewed.
D Topological Indoor Building Modeling Integrated with Open Street Map
NASA Astrophysics Data System (ADS)
Jamali, A.; Rahman, A. Abdul; Boguslawski, P.
2016-09-01
Considering various fields of applications for building surveying and various demands, geometry representation of a building is the most crucial aspect of a building survey. The interiors of the buildings need to be described along with the relative locations of the rooms, corridors, doors and exits in many kinds of emergency response, such as fire, bombs, smoke, and pollution. Topological representation is a challenging task within the Geography Information Science (GIS) environment, as the data structures required to express these relationships are particularly difficult to develop. Even within the Computer Aided Design (CAD) community, the structures for expressing the relationships between adjacent building parts are complex and often incomplete. In this paper, an integration of 3D topological indoor building modeling in Dual Half Edge (DHE) data structure and outdoor navigation network from Open Street Map (OSM) is presented.
NASA Astrophysics Data System (ADS)
Gibson, J. Murray
2009-05-01
Probably the most prolific use of large accelerators today is in the creation of bright beams of x-ray photons or neutrons. The number of scientific users of such sources in the US alone is approaching 10,000. I will describe the some of the major applications of synchrotron and neutron radiation and their impact on society. If you have AIDS, need a better IPOD or a more efficient car, or want to clean up a superfund site, you are benefitting from these accelerators. The design of new materials is becoming more and more dependent on structural information from these sources. I will identify the trends in applications which are demanding new sources with greater capabilities.
A compact light-sheet microscope for the study of the mammalian central nervous system
Yang, Zhengyi; Haslehurst, Peter; Scott, Suzanne; Emptage, Nigel; Dholakia, Kishan
2016-01-01
Investigation of the transient processes integral to neuronal function demands rapid and high-resolution imaging techniques over a large field of view, which cannot be achieved with conventional scanning microscopes. Here we describe a compact light sheet fluorescence microscope, featuring a 45° inverted geometry and an integrated photolysis laser, that is optimized for applications in neuroscience, in particular fast imaging of sub-neuronal structures in mammalian brain slices. We demonstrate the utility of this design for three-dimensional morphological reconstruction, activation of a single synapse with localized photolysis, and fast imaging of neuronal Ca2+ signalling across a large field of view. The developed system opens up a host of novel applications for the neuroscience community. PMID:27215692
2D lateral heterostructures of group-III monochalcogenide: Potential photovoltaic applications
NASA Astrophysics Data System (ADS)
Cheng, Kai; Guo, Yu; Han, Nannan; Jiang, Xue; Zhang, Junfeng; Ahuja, Rajeev; Su, Yan; Zhao, Jijun
2018-04-01
Solar photovoltaics provides a practical and sustainable solution to the increasing global energy demand. Using first-principles calculations, we investigate the energetics and electronic properties of two-dimensional lateral heterostructures by group-III monochalcogenides and explore their potential applications in photovoltaics. The band structures and formation energies from supercell calculations demonstrate that these heterostructures retain semiconducting behavior and might be synthesized in laboratory using the chemical vapor deposition technique. According to the computed band offsets, most of the heterojunctions belong to type II band alignment, which can prevent the recombination of electron-hole pairs. Besides, the electronic properties of these lateral heterostructures can be effectively tailored by the number of layers, leading to a high theoretical power conversion efficiency over 20%.
NASA/CARES dual-use ceramic technology spinoff applications
NASA Technical Reports Server (NTRS)
Powers, Lynn M.; Janosik, Lesley A.; Gyekenyesi, John P.; Nemeth, Noel N.
1994-01-01
NASA has developed software that enables American industry to establish the reliability and life of ceramic structures in a wide variety of 21st Century applications. Designing ceramic components to survive at higher temperatures than the capability of most metals and in severe loading environments involves the disciplines of statistics and fracture mechanics. Successful application of advanced ceramics material properties and the use of a probabilistic brittle material design methodology. The NASA program, known as CARES (Ceramics Analysis and Reliability Evaluation of Structures), is a comprehensive general purpose design tool that predicts the probability of failure of a ceramic component as a function of its time in service. The latest version of this software, CARESALIFE, is coupled to several commercially available finite element analysis programs (ANSYS, MSC/NASTRAN, ABAQUS, COSMOS/N4, MARC), resulting in an advanced integrated design tool which is adapted to the computing environment of the user. The NASA-developed CARES software has been successfully used by industrial, government, and academic organizations to design and optimize ceramic components for many demanding applications. Industrial sectors impacted by this program include aerospace, automotive, electronic, medical, and energy applications. Dual-use applications include engine components, graphite and ceramic high temperature valves, TV picture tubes, ceramic bearings, electronic chips, glass building panels, infrared windows, radiant heater tubes, heat exchangers, and artificial hips, knee caps, and teeth.
Reduction of peak energy demand based on smart appliances energy consumption adjustment
NASA Astrophysics Data System (ADS)
Powroźnik, P.; Szulim, R.
2017-08-01
In the paper the concept of elastic model of energy management for smart grid and micro smart grid is presented. For the proposed model a method for reducing peak demand in micro smart grid has been defined. The idea of peak demand reduction in elastic model of energy management is to introduce a balance between demand and supply of current power for the given Micro Smart Grid in the given moment. The results of the simulations studies were presented. They were carried out on real household data available on UCI Machine Learning Repository. The results may have practical application in the smart grid networks, where there is a need for smart appliances energy consumption adjustment. The article presents a proposal to implement the elastic model of energy management as the cloud computing solution. This approach of peak demand reduction might have application particularly in a large smart grid.
DOT National Transportation Integrated Search
2017-07-01
The primary objective of this project is to develop multiple simulation testbeds and transportation models to evaluate the impacts of Connected Vehicle Dynamic Mobility Applications (DMA) and Active Transportation and Demand Management (ATDM) strateg...
DOT National Transportation Integrated Search
2017-07-01
The primary objective of this project is to develop multiple simulation testbeds and transportation models to evaluate the impacts of Connected Vehicle Dynamic Mobility Applications (DMA) and Active Transportation and Demand Management (ATDM) strateg...
DOT National Transportation Integrated Search
2017-08-01
The primary objective of this project is to develop multiple simulation testbeds and transportation models to evaluate the impacts of Connected Vehicle Dynamic Mobility Applications (DMA) and Active Transportation and Demand Management (ATDM) strateg...
Hoffmann, K T; Anders, N; Hosten, N; Holschbach, A; Walkow, T; Sörensen, R; Hartmann, C; Felix, R
1998-08-01
Both dacryocystography and dacryoscintigraphy are well established in the evaluation of stenoses of the lacrimal drainage system. They provide limited information about the ductal anatomy itself and about periductal structures. MR imaging was evaluated for its capability to directly visualize the lacrimal drainage system in detail and simultaneously provide functional characterization of dacryostenosis. Twenty-seven lacrimal drainage systems of 23 patients suffering from epiphora were examined in an MR unit before and after conjunctival and intravenous application of Gd-DTPA using a surface coil. Dacryostenosis was found in 23 of 27 lacrimal systems. Stenoses were localized to the canalicular (n = 3), saccular (n = 8), and ductal (n = 12) level, and were classified as stenosis or occlusion. MR imaging with conjunctival contrast application allows within one examination both detailed morphological and functional assessment of the lacrimal drainage system with depiction of surrounding structures. Limitations arise mainly from demands on technical and patient-related preconditions.
Kohler, Amanda C; Simmons, Blake A; Sale, Kenneth L
2018-04-28
In an age of ever-increasing biotechnological and industrial demand for new and specialized biocatalysts, rational protein engineering offers a direct approach to enzyme design and innovation. Heme peroxidases, as indispensable oxidative biocatalysts, provide a relatively mild alternative to the traditional harsh, and often toxic, chemical catalysts, and subsequently, have found widespread application throughout industry. However, the potential for these enzymes is far greater than their present use, as processes are currently restricted to the more stable, but less catalytically powerful, subset of peroxidases. Here we describe the structure-guided, rational engineering of a plant-fungal hybrid peroxidase built to overcome the application barrier of these high-reduction potential peroxidases. This engineered enzyme has the catalytic versatility and oxidative ability of a high-reduction potential versatile peroxidase, with enhanced temperature and pH tolerance similar to that of a highly stable plant peroxidase. Copyright © 2018 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Zhou, Peng; Zheng, Gaige
2018-04-01
The efficiency of graphene-based optoelectronic devices is typically limited by the poor absolute absorption of light. A hybrid structure of monolayer graphene with cylindrical titanium dioxide (TiO2) array and aluminum oxide (Al2O3) spacer layer on aluminum (Al) substrate has been proposed to enhance the absorption for two-dimensional (2D) materials. By combining dielectric array with metal substrate, the structure achieves multiple absorption peaks with near unity absorbance at near-infrared wavelengths due to the resonant effect of dielectric array. Completed monolayer graphene is utilized in the design without any demand of manufacture process to form the periodic patterns. Further analysis indicates that the near-field enhancement induced by surface modes gives rise to the high absorption. This favorable field enhancement and tunability of absorption not only open up new approaches to accelerate the light-graphene interaction, but also show great potential for practical applications in high-performance optoelectronic devices, such as modulators and sensors.
Modeling and fabrication of 4H-SiC Schottky junction
NASA Astrophysics Data System (ADS)
Martychowiec, A.; Pedryc, A.; Kociubiński, A.
2017-08-01
The rapidly growing demand for electronic devices requires using of alternative semiconductor materials, which could replace conventional silicon. Silicon carbide has been proposed for these harsh environment applications (high temperature, high voltage, high power conditions) because of its wide bandgap, its high temperature operation ability, its excellent thermal and chemical stability, and its high breakdown electric field strength. The Schottky barrier diode (SBD) is known as one of the best refined SiC devices. This paper presents prepared model, simulations and description of technology of 4H-SiC Schottky junction as well as characterization of fabricated structures. The future aim of the application of the structures is an optical detection of an ultraviolet radiation. The model section contains a comparison of two different solutions of SBD's construction. Simulations - as a crucial process of designing electronic devices - have been performed using the ATLAS device of Silvaco TCAD software. As a final result the paper shows I-V characteristics of fabricated diodes.
Multimodal inspection in power engineering and building industries: new challenges and solutions
NASA Astrophysics Data System (ADS)
Kujawińska, Małgorzata; Malesa, Marcin; Malowany, Krzysztof
2013-09-01
Recently the demand and number of applications of full-field, optical measurement methods based on noncoherent light sources increased significantly. They include traditional image processing, thermovision, digital image correlation (DIC) and structured light methods. However, there are still numerous challenges connected with implementation of these methods to in-situ, long-term monitoring in industrial, civil engineering and cultural heritage applications, multimodal measurements of a variety of object features or simply adopting instruments to work in hard environmental conditions. In this paper we focus on 3D DIC method and present its enhancements concerning software modifications (new visualization methods and a method for automatic merging of data distributed in time) and hardware improvements. The modified 3D DIC system combined with infrared camera system is applied in many interesting cases: measurements of boiler drum during annealing and of pipelines in heat power stations and monitoring of different building steel struts at construction site and validation of numerical models of large building structures constructed of graded metal plate arches.
Jia, Yuechen; Cheng, Chen; Vázquez de Aldana, Javier R; Castillo, Gabriel R; Rabes, Blanca del Rosal; Tan, Yang; Jaque, Daniel; Chen, Feng
2014-08-07
Miniature laser sources with on-demand beam features are desirable devices for a broad range of photonic applications. Lasing based on direct-pump of miniaturized waveguiding active structures offers a low-cost but intriguing solution for compact light-emitting devices. In this work, we demonstrate a novel family of three dimensional (3D) photonic microstructures monolithically integrated in a Nd:YAG laser crystal wafer. They are produced by the femtosecond laser writing, capable of simultaneous light waveguiding and beam manipulation. In these guiding systems, tailoring of laser modes by both passive/active beam splitting and ring-shaped transformation are achieved by an appropriate design of refractive index patterns. Integration of graphene thin-layer as saturable absorber in the 3D laser structures allows for efficient passive Q-switching of tailored laser radiations which may enable miniature waveguiding lasers for broader applications. Our results pave a way to construct complex integrated passive and active laser circuits in dielectric crystals by using femtosecond laser written monolithic photonic chips.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Emery, John M.; Coffin, Peter; Robbins, Brian A.
Microstructural variabilities are among the predominant sources of uncertainty in structural performance and reliability. We seek to develop efficient algorithms for multiscale calcu- lations for polycrystalline alloys such as aluminum alloy 6061-T6 in environments where ductile fracture is the dominant failure mode. Our approach employs concurrent multiscale methods, but does not focus on their development. They are a necessary but not sufficient ingredient to multiscale reliability predictions. We have focused on how to efficiently use concurrent models for forward propagation because practical applications cannot include fine-scale details throughout the problem domain due to exorbitant computational demand. Our approach begins withmore » a low-fidelity prediction at the engineering scale that is sub- sequently refined with multiscale simulation. The results presented in this report focus on plasticity and damage at the meso-scale, efforts to expedite Monte Carlo simulation with mi- crostructural considerations, modeling aspects regarding geometric representation of grains and second-phase particles, and contrasting algorithms for scale coupling.« less
Application of a distributed network in computational fluid dynamic simulations
NASA Technical Reports Server (NTRS)
Deshpande, Manish; Feng, Jinzhang; Merkle, Charles L.; Deshpande, Ashish
1994-01-01
A general-purpose 3-D, incompressible Navier-Stokes algorithm is implemented on a network of concurrently operating workstations using parallel virtual machine (PVM) and compared with its performance on a CRAY Y-MP and on an Intel iPSC/860. The problem is relatively computationally intensive, and has a communication structure based primarily on nearest-neighbor communication, making it ideally suited to message passing. Such problems are frequently encountered in computational fluid dynamics (CDF), and their solution is increasingly in demand. The communication structure is explicitly coded in the implementation to fully exploit the regularity in message passing in order to produce a near-optimal solution. Results are presented for various grid sizes using up to eight processors.
High-power microwave LDMOS transistors for wireless data transmission technologies (Review)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kuznetsov, E. V., E-mail: E.Kouzntsov@tcen.ru; Shemyakin, A. V.
The fields of the application, structure, fabrication, and packaging technology of high-power microwave LDMOS transistors and the main advantages of these devices were analyzed. Basic physical parameters and some technology factors were matched for optimum device operation. Solid-state microwave electronics has been actively developed for the last 10-15 years. Simultaneously with improvement of old devices, new devices and structures are actively being adopted and developed and new semiconductor materials are being commercialized. Microwave LDMOS technology is in demand in such fields as avionics, civil and military radars, repeaters, base stations of cellular communication systems, television and broadcasting transmitters, and transceiversmore » for high-speed wireless computer networks (promising Wi-Fi and Wi-Max standards).« less
A novel percussion type droplet-on-demand generator
NASA Astrophysics Data System (ADS)
Hussain, Taaha; Patel, Priyesh; Balachandran, Ramanarayanan; Ladommatos, Nicos
2015-01-01
Numerous engineering applications require generation of droplets on demand which are of high uniformity and constant size. The common method to produce droplets is to drive liquid at high pressure through a small orifice/nozzle. The liquid stream disintegrates into small droplets. However this method normally requires large volumes of liquid and is not suitable for applications where single droplets of constant size is required. Such applications require droplet-on-demand generators which commonly employ piezoelectric or pneumatic actuation. It is well known that piezoelectric generators are hard to employ at high pressure and, high temperature applications, and the pneumatic generators often produce satellite (secondary) droplets. This paper describes the development of a novel percussion type droplet-on-demand generator, which overcomes some of the above difficulties and is capable of producing single droplets on demand. The generator consists of a cylindrical liquid filled chamber with a small orifice at the bottom. The top of the chamber is covered with a thin flexible metal disc. A small metal pin is employed to hammer/impact the top metal surface to generate a pressure pulse inside the liquid chamber. The movement and the momentum of the metal pin are controlled using a solenoid device. The pressure pulse generated overcomes the surface tension of the liquid meniscus at the exit of the orifice and ejects a single droplet. The work presented in this paper will demonstrate the capabilities of the droplet generator.
Recent Developments of Graphene Oxide-Based Membranes: A Review
Ma, Jinxia; Ping, Dan; Dong, Xinfa
2017-01-01
Membrane-based separation technology has attracted great interest in many separation fields due to its advantages of easy-operation, energy-efficiency, easy scale-up, and environmental friendliness. The development of novel membrane materials and membrane structures is an urgent demand to promote membrane-based separation technology. Graphene oxide (GO), as an emerging star nano-building material, has showed great potential in the membrane-based separation field. In this review paper, the latest research progress in GO-based membranes focused on adjusting membrane structure and enhancing their mechanical strength as well as structural stability in aqueous environment is highlighted and discussed in detail. First, we briefly reviewed the preparation and characterization of GO. Then, the preparation method, characterization, and type of GO-based membrane are summarized. Finally, the advancements of GO-based membrane in adjusting membrane structure and enhancing their mechanical strength, as well as structural stability in aqueous environment, are particularly discussed. This review hopefully provides a new avenue for the innovative developments of GO-based membrane in various membrane applications. PMID:28895877
In-service health monitoring of composite structures
NASA Technical Reports Server (NTRS)
Pinto, Gino A.; Ventres, C. S.; Ginty, Carol A.; Chamis, Christos C.
1990-01-01
The aerospace industry is witnessing a vast utilization of composites in critical structural applications and anticipates even more use of them in future aircraft. Therefore, a definite need exists for a composite health monitoring expert system to meet today's current needs and tomorrow's future demands. The primary goal for this conceptual health monitoring system is functional reliably for in-service operation in the environments of various composite structures. The underlying philosophy of this system is to utilize proven vibration techniques to assess the structural integrity of a fibrous composite. Statistical methods are used to determine if the variances in the measured data are acceptable for making a reliable decision on the health status of the composite. The flexible system allows for algorithms describing any composite fatigue or damage behavior characteristic to be provided as an input to the system. Alert thresholds and variances can also be provided as an input to this system and may be updated to allow for future changes/refinements in the composite's structural integrity behavior.
Recent Developments of Graphene Oxide-Based Membranes: A Review.
Ma, Jinxia; Ping, Dan; Dong, Xinfa
2017-09-12
Membrane-based separation technology has attracted great interest in many separation fields due to its advantages of easy-operation, energy-efficiency, easy scale-up, and environmental friendliness. The development of novel membrane materials and membrane structures is an urgent demand to promote membrane-based separation technology. Graphene oxide (GO), as an emerging star nano-building material, has showed great potential in the membrane-based separation field. In this review paper, the latest research progress in GO-based membranes focused on adjusting membrane structure and enhancing their mechanical strength as well as structural stability in aqueous environment is highlighted and discussed in detail. First, we briefly reviewed the preparation and characterization of GO. Then, the preparation method, characterization, and type of GO-based membrane are summarized. Finally, the advancements of GO-based membrane in adjusting membrane structure and enhancing their mechanical strength, as well as structural stability in aqueous environment, are particularly discussed. This review hopefully provides a new avenue for the innovative developments of GO-based membrane in various membrane applications.
Demand of the power industry of Russia for gas turbines: the current state and prospects
NASA Astrophysics Data System (ADS)
Filippov, S. P.; Dil'man, M. D.; Ionov, M. S.
2017-11-01
The use of gas-turbine plants (GTPs) in the power industry of Russia is analyzed. Attention is paid to microturbines and low-, medium-, high-, and superhigh-power GTPs. The efficiency of the gas-turbine plants of domestic and foreign manufacture is compared. The actual values of the installed capacity utilization factor and the corresponding efficiency values are calculated for most GTPs operating in the country. The long-term demand of the country's electric power industry for GTPs for the period until 2040 is determined. The estimates have been obtained for three basic applications of the gas turbines, viz., for replacement of the GTPs that have exhausted their lifetime, replacement of outdated gas-turbine plants at gas-and-oilburning power plants, and construction of new thermal power plants to cover the anticipated growing demand for electric power. According to the findings of the research, the main item in the structure of the demand for GTPs will be their use to replace the decommissioned steam-turbine plants, predominantly those integrated into combined-cycle plants. The priority of the reconstruction of the thermal power plants in operation over the construction of new ones is determined by the large excess of accumulated installed capacities in the country and considerable savings on capital costs using production sites with completed infrastructure. It is established that medium- and high-power GTPs will be the most in-demand plants in the electric power industry. The demand for low-power GTPs will increase at high rates. The demand for microturbines is expected to be rather great. The demand for superhigh-power plants will become quantitatively significant after 2025 and grow rapidly afterwards. The necessity of accelerated development of competitive domestic GTPs with a wide range of capacities and mastering of their series manufacture as well as production of licensed gas turbines at a high production localization level on the territory of the country is shown. Considerable home demand for the power-generating GTPs and vast external markets will make the development of efficient domestic GTPs economically viable.
Using Enrollment Demand Models in Institutional Pricing Decisions.
ERIC Educational Resources Information Center
Weiler, William C.
1984-01-01
Issues in the application of enrollment demand analysis to institutions' pricing policy are discussed, including price change impact on enrollment, the role of enrollment demand models on long-range financial and personnel planning, use of tuition and financial aid policy in optimizing policymakers' enrollment objectives, and the redistribution…
Singh, Sunil; Gupta, Rashi; Kumari, Madhu; Sharma, Shilpi
2015-08-01
Intensive agriculture has resulted in an indiscriminate use of pesticides, which demands in-depth analysis of their impact on indigenous rhizospheric microbial community structure and function. Hence, the objective of the present work was to study the impact of two chemical pesticides (chlorpyrifos and cypermethrin) and one biological pesticide (azadirachtin) at two dosages on the microbial community structure using cultivation-dependent approach and on rhizospheric bacterial communities involved in nitrogen cycle in Vigna radiata rhizosphere through cultivation-independent technique of real-time PCR. Cultivation-dependent study highlighted the adverse effects of both chemical pesticide and biopesticide on rhizospheric bacterial and fungal communities at different plant growth stages. Also, an adverse effect on number of genes and transcripts of nifH (nitrogen fixation); amoA (nitrification); and narG, nirK, and nirS (denitrification) was observed. The results from the present study highlighted two points, firstly that nontarget effects of pesticides are significantly detrimental to soil microflora, and despite being of biological origin, azadirachtin exerted negative impact on rhizospheric microbial community of V. radiata behaving similar to chemical pesticides. Hence, such nontarget effects of chemical pesticide and biopesticide in plants' rhizosphere, which bring out the larger picture in terms of their ecotoxicological effect, demand a proper risk assessment before application of pesticides as agricultural amendments.
Coping with Unemployment: Personality, Role Demands, and Time Structure
ERIC Educational Resources Information Center
Van Hoye, Greet; Lootens, Hanne
2013-01-01
Time structure has been found to be an important coping mechanism for dealing with the negative effects of unemployment on psychological well-being. This study extends the literature by investigating personality (openness to experience, conscientiousness, extraversion, neuroticism, and proactivity) and role demands (marital status, being the only…
Modeling and Analysis of Commercial Building Electrical Loads for Demand Side Management
NASA Astrophysics Data System (ADS)
Berardino, Jonathan
In recent years there has been a push in the electric power industry for more customer involvement in the electricity markets. Traditionally the end user has played a passive role in the planning and operation of the power grid. However, many energy markets have begun opening up opportunities to consumers who wish to commit a certain amount of their electrical load under various demand side management programs. The potential benefits of more demand participation include reduced operating costs and new revenue opportunities for the consumer, as well as more reliable and secure operations for the utilities. The management of these load resources creates challenges and opportunities to the end user that were not present in previous market structures. This work examines the behavior of commercial-type building electrical loads and their capacity for supporting demand side management actions. This work is motivated by the need for accurate and dynamic tools to aid in the advancement of demand side operations. A dynamic load model is proposed for capturing the response of controllable building loads. Building-specific load forecasting techniques are developed, with particular focus paid to the integration of building management system (BMS) information. These approaches are tested using Drexel University building data. The application of building-specific load forecasts and dynamic load modeling to the optimal scheduling of multi-building systems in the energy market is proposed. Sources of potential load uncertainty are introduced in the proposed energy management problem formulation in order to investigate the impact on the resulting load schedule.
Ubiquitous Green Computing Techniques for High Demand Applications in Smart Environments
Zapater, Marina; Sanchez, Cesar; Ayala, Jose L.; Moya, Jose M.; Risco-Martín, José L.
2012-01-01
Ubiquitous sensor network deployments, such as the ones found in Smart cities and Ambient intelligence applications, require constantly increasing high computational demands in order to process data and offer services to users. The nature of these applications imply the usage of data centers. Research has paid much attention to the energy consumption of the sensor nodes in WSNs infrastructures. However, supercomputing facilities are the ones presenting a higher economic and environmental impact due to their very high power consumption. The latter problem, however, has been disregarded in the field of smart environment services. This paper proposes an energy-minimization workload assignment technique, based on heterogeneity and application-awareness, that redistributes low-demand computational tasks from high-performance facilities to idle nodes with low and medium resources in the WSN infrastructure. These non-optimal allocation policies reduce the energy consumed by the whole infrastructure and the total execution time. PMID:23112621
Ubiquitous green computing techniques for high demand applications in Smart environments.
Zapater, Marina; Sanchez, Cesar; Ayala, Jose L; Moya, Jose M; Risco-Martín, José L
2012-01-01
Ubiquitous sensor network deployments, such as the ones found in Smart cities and Ambient intelligence applications, require constantly increasing high computational demands in order to process data and offer services to users. The nature of these applications imply the usage of data centers. Research has paid much attention to the energy consumption of the sensor nodes in WSNs infrastructures. However, supercomputing facilities are the ones presenting a higher economic and environmental impact due to their very high power consumption. The latter problem, however, has been disregarded in the field of smart environment services. This paper proposes an energy-minimization workload assignment technique, based on heterogeneity and application-awareness, that redistributes low-demand computational tasks from high-performance facilities to idle nodes with low and medium resources in the WSN infrastructure. These non-optimal allocation policies reduce the energy consumed by the whole infrastructure and the total execution time.
Solar San Diego: The Impact of Binomial Rate Structures on Real PV-Systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Van Geet, O.; Brown, E.; Blair, T.
2008-01-01
There is confusion in the marketplace regarding the impact of solar photovoltaics (PV) on the user's actual electricity bill under California Net Energy Metering, particularly with binomial tariffs (those that include both demand and energy charges) and time-of-use (TOU) rate structures. The City of San Diego has extensive real-time electrical metering on most of its buildings and PV systems, with interval data for overall consumption and PV electrical production available for multiple years. This paper uses 2007 PV-system data from two city facilities to illustrate the impacts of binomial rate designs. The analysis will determine the energy and demand savingsmore » that the PV systems are achieving relative to the absence of systems. A financial analysis of PV-system performance under various rates structures is presented. The data revealed that actual demand and energy use benefits of bionomial tariffs increase in summer months, when solar resources allow for maximized electricity production. In a binomial tariff system, varying on- and semi-peak times can result in approximately $1,100 change in demand charges per month over not having a PV system in place, an approximate 30% cost savings. The PV systems are also shown to have a 30%-50% reduction in facility energy charges in 2007. Future work will include combining demand and electricity charges and increasing the breadth of rate structures tested, including the impacts of non-coincident demand charges.« less
Shang, Yizi; Lu, Shibao; Gong, Jiaguo; Shang, Ling; Li, Xiaofei; Wei, Yongping; Shi, Hongwang
2017-12-01
A recent study decomposed the changes in industrial water use into three hierarchies (output, technology, and structure) using a refined Laspeyres decomposition model, and found monotonous and exclusive trends in the output and technology hierarchies. Based on that research, this study proposes a hierarchical prediction approach to forecast future industrial water demand. Three water demand scenarios (high, medium, and low) were then established based on potential future industrial structural adjustments, and used to predict water demand for the structural hierarchy. The predictive results of this approach were compared with results from a grey prediction model (GPM (1, 1)). The comparison shows that the results of the two approaches were basically identical, differing by less than 10%. Taking Tianjin, China, as a case, and using data from 2003-2012, this study predicts that industrial water demand will continuously increase, reaching 580 million m 3 , 776.4 million m 3 , and approximately 1.09 billion m 3 by the years 2015, 2020 and 2025 respectively. It is concluded that Tianjin will soon face another water crisis if no immediate measures are taken. This study recommends that Tianjin adjust its industrial structure with water savings as the main objective, and actively seek new sources of water to increase its supply.
Parallel, distributed and GPU computing technologies in single-particle electron microscopy
Schmeisser, Martin; Heisen, Burkhard C.; Luettich, Mario; Busche, Boris; Hauer, Florian; Koske, Tobias; Knauber, Karl-Heinz; Stark, Holger
2009-01-01
Most known methods for the determination of the structure of macromolecular complexes are limited or at least restricted at some point by their computational demands. Recent developments in information technology such as multicore, parallel and GPU processing can be used to overcome these limitations. In particular, graphics processing units (GPUs), which were originally developed for rendering real-time effects in computer games, are now ubiquitous and provide unprecedented computational power for scientific applications. Each parallel-processing paradigm alone can improve overall performance; the increased computational performance obtained by combining all paradigms, unleashing the full power of today’s technology, makes certain applications feasible that were previously virtually impossible. In this article, state-of-the-art paradigms are introduced, the tools and infrastructure needed to apply these paradigms are presented and a state-of-the-art infrastructure and solution strategy for moving scientific applications to the next generation of computer hardware is outlined. PMID:19564686
Finishing of additively manufactured titanium alloy by shape adaptive grinding (SAG)
NASA Astrophysics Data System (ADS)
Beaucamp, Anthony T.; Namba, Yoshiharu; Charlton, Phillip; Jain, Samyak; Graziano, Arthur A.
2015-06-01
In recent years, rapid prototyping of titanium alloy components for medical and aeronautics application has become viable thanks to advances in technologies such as electron beam melting (EBM) and selective laser sintering (SLS). However, for many applications the high surface roughness generated by additive manufacturing techniques demands a post-finishing operation to improve the surface quality prior to usage. In this paper, the novel shape adaptive grinding process has been applied to finishing titanium alloy (Ti6Al4V) additively manufactured by EBM and SLS. It is shown that the micro-structured surface layer resulting from the melting process can be removed, and the surface can then be smoothed down to less than 10 nm Ra (starting from 4-5 μm Ra) using only three different diamond grit sizes. This paper also demonstrates application of the technology to freeform shapes, and documents the dimensional accuracy of finished artifacts.
NASA Technical Reports Server (NTRS)
Nguyen, Baochau N.; Guo, Haiquan N.; McCorkle, Linda S.
2014-01-01
As aerospace applications become ever more demanding, novel insulation materials with lower thermal conductivity, lighter weight and higher use temperature are required to fit the aerospace application needs. Having nanopores and high porosity, aerogels are superior thermal insulators, among other things. The use of silica aerogels in general is quite restricted due to their inherent fragility, hygroscopic nature, and poor mechanical properties, especially in extereme aerospace environments. Our research goal is to develop aerogels with better mechanical and environmental stability for a variety of aeronautic and space applications including space suit insulation for planetary surface missions, insulation for inflatable structures for habitats, inflatable aerodynamic decelerators for entry, descent and landing (EDL) operations, and cryotank insulation for advance space propulsion systems. Different type of aerogels including organic-inorganic polymer reinforced (hybrid) silica-based aerogels, polyimide aerogels and inorganic aluminosilicate aerogels have been developed and examined.
Design of transnational mobile e-payment application based on SIM card
NASA Astrophysics Data System (ADS)
Qian, Tang; Zhen, Li
2018-05-01
Facing the stronger demands of transnational mobile communications and internet-based mobile wireless value-added services, the interconnection and interworking of multiple communication operators and their win-win cooperations become a crucial target in the new round of mobile economic development. Previous researches showed that mobile communications and value-add services are not only technical problems, but also more economic problems.we design a general oncard operating system based on SIM card that could be responsible for coordinating and distributing card hardware and software resources. These applications such as transnational mobile payment, consumption management and many other supplemented functions share the API interfaces, hardware and software resources provided by the operation system, although they are independent of each other. The layer structure of SIM card design not only greatly reduces the complexity of COS development, but also saves the most tense card resources and extends SIM cards applications.
Parallel, distributed and GPU computing technologies in single-particle electron microscopy.
Schmeisser, Martin; Heisen, Burkhard C; Luettich, Mario; Busche, Boris; Hauer, Florian; Koske, Tobias; Knauber, Karl-Heinz; Stark, Holger
2009-07-01
Most known methods for the determination of the structure of macromolecular complexes are limited or at least restricted at some point by their computational demands. Recent developments in information technology such as multicore, parallel and GPU processing can be used to overcome these limitations. In particular, graphics processing units (GPUs), which were originally developed for rendering real-time effects in computer games, are now ubiquitous and provide unprecedented computational power for scientific applications. Each parallel-processing paradigm alone can improve overall performance; the increased computational performance obtained by combining all paradigms, unleashing the full power of today's technology, makes certain applications feasible that were previously virtually impossible. In this article, state-of-the-art paradigms are introduced, the tools and infrastructure needed to apply these paradigms are presented and a state-of-the-art infrastructure and solution strategy for moving scientific applications to the next generation of computer hardware is outlined.
Application of DNA-based methods in forensic entomology.
Wells, Jeffrey D; Stevens, Jamie R
2008-01-01
A forensic entomological investigation can benefit from a variety of widely practiced molecular genotyping methods. The most commonly used is DNA-based specimen identification. Other applications include the identification of insect gut contents and the characterization of the population genetic structure of a forensically important insect species. The proper application of these procedures demands that the analyst be technically expert. However, one must also be aware of the extensive list of standards and expectations that many legal systems have developed for forensic DNA analysis. We summarize the DNA techniques that are currently used in, or have been proposed for, forensic entomology and review established genetic analyses from other scientific fields that address questions similar to those in forensic entomology. We describe how accepted standards for forensic DNA practice and method validation are likely to apply to insect evidence used in a death or other forensic entomological investigation.
Examination of the Residency Interview Process for Academic Pathology Departments
2016-01-01
Annual resident recruitment is a complex undertaking that requires many departmental resources of faculty time and effort and in many cases financial investment for meals and lodging. The applicants represent the future of the profession as well as the providers of patient care in the respective training programs. Although we understand the importance of this process, as we become more and more distracted by financial, administrative, and academic duties, the demands of recruitment have not decreased and continue annually. In an attempt to find the best practices for the improvement in our methods of recruitment, a review of the literature on the employment interviews with a specific eye to pathology residency relevant information was conducted. This article reviews some of the factors proven to be important to the applicants as well as an examination of the structure of the interview and the postinterview applicant evaluation process. PMID:28725755
Bioinspired Nanoscale Materials for Biomedical and Energy Applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bhattacharya, Priyanka; Du, Dan; Lin, Yuehe
2014-05-01
The demand of green, affordable and environmentally sustainable materials has encouraged scientists in different fields to draw inspiration from nature in developing materials with unique properties such as miniaturization, hierarchical organization, and adaptability. Together with the exceptional properties of nanomaterials, over the past century, the field of bioinspired nanomaterials has taken huge leaps. While on one hand, the sophistication of hierarchical structures endow biological systems with multifunctionality, the synthetic control on the creation of nanomaterials enables the design of materials with specific functionalities. The aim of this review is to provide a comprehensive, up-to-date overview of the field of bioinspiredmore » nanomaterials, which we have broadly categorized into biotemplates and biomimics. We will discuss the application of bioinspired nanomaterials as biotemplates in catalysis, nanomedicine, immunoassays and in energy, drawing attention to novel materials such as protein cages. Further, the applications of bioinspired materials in tissue engineering and biomineralization will also be discussed.« less
Non-invasive light-weight integration engine for building EHR from autonomous distributed systems.
Crespo Molina, Pere; Angulo Fernández, Carlos; Maldonado Segura, José A; Moner Cano, David; Robles Viejo, Montserrat
2006-01-01
Pangea-LE is a message oriented light-weight integration engine, allowing concurrent access to clinical information from disperse and heterogeneous data sources. The engine extracts the information and serves it to the requester client applications in a flexible XML format. This XML response message can be formatted on demand by the appropriate XSL (Extensible Stylesheet Language) transformation in order to fit client application needs. In this article we present a real use case sample where Pangea-LE collects and generates "on the fly" a structured view of all the patient clinical information available in a healthcare organisation. This information is presented to healthcare professionals in an EHR (Electronic Health Record) viewer Web application with patient search and EHR browsing capabilities. Implantation in a real environment has been a notable success due to the non-invasive method which extremely respects the existing information systems.
Grundy, Lorena S; Lee, Victoria E; Li, Nannan; Sosa, Chris; Mulhearn, William D; Liu, Rui; Register, Richard A; Nikoubashman, Arash; Prud'homme, Robert K; Panagiotopoulos, Athanassios Z; Priestley, Rodney D
2018-05-08
Colloids with internally structured geometries have shown great promise in applications ranging from biosensors to optics to drug delivery, where the internal particle structure is paramount to performance. The growing demand for such nanomaterials necessitates the development of a scalable processing platform for their production. Flash nanoprecipitation (FNP), a rapid and inherently scalable colloid precipitation technology, is used to prepare internally structured colloids from blends of block copolymers and homopolymers. As revealed by a combination of experiments and simulations, colloids prepared from different molecular weight diblock copolymers adopt either an ordered lamellar morphology consisting of concentric shells or a disordered lamellar morphology when chain dynamics are sufficiently slow to prevent defect annealing during solvent exchange. Blends of homopolymer and block copolymer in the feed stream generate more complex internally structured colloids, such as those with hierarchically structured Janus and patchy morphologies, due to additional phase separation and kinetic trapping effects. The ability of the FNP process to generate such a wide range of morphologies using a simple and scalable setup provides a pathway to manufacturing internally structured colloids on an industrial scale.
Seismic and Restoration Assessment of Monumental Masonry Structures
Asteris, Panagiotis G.; Douvika, Maria G.; Apostolopoulou, Maria; Moropoulou, Antonia
2017-01-01
Masonry structures are complex systems that require detailed knowledge and information regarding their response under seismic excitations. Appropriate modelling of a masonry structure is a prerequisite for a reliable earthquake-resistant design and/or assessment. However, modelling a real structure with a robust quantitative (mathematical) representation is a very difficult, complex and computationally-demanding task. The paper herein presents a new stochastic computational framework for earthquake-resistant design of masonry structural systems. The proposed framework is based on the probabilistic behavior of crucial parameters, such as material strength and seismic characteristics, and utilizes fragility analysis based on different failure criteria for the masonry material. The application of the proposed methodology is illustrated in the case of a historical and monumental masonry structure, namely the assessment of the seismic vulnerability of the Kaisariani Monastery, a byzantine church that was built in Athens, Greece, at the end of the 11th to the beginning of the 12th century. Useful conclusions are drawn regarding the effectiveness of the intervention techniques used for the reduction of the vulnerability of the case-study structure, by means of comparison of the results obtained. PMID:28767073
Seismic and Restoration Assessment of Monumental Masonry Structures.
Asteris, Panagiotis G; Douvika, Maria G; Apostolopoulou, Maria; Moropoulou, Antonia
2017-08-02
Masonry structures are complex systems that require detailed knowledge and information regarding their response under seismic excitations. Appropriate modelling of a masonry structure is a prerequisite for a reliable earthquake-resistant design and/or assessment. However, modelling a real structure with a robust quantitative (mathematical) representation is a very difficult, complex and computationally-demanding task. The paper herein presents a new stochastic computational framework for earthquake-resistant design of masonry structural systems. The proposed framework is based on the probabilistic behavior of crucial parameters, such as material strength and seismic characteristics, and utilizes fragility analysis based on different failure criteria for the masonry material. The application of the proposed methodology is illustrated in the case of a historical and monumental masonry structure, namely the assessment of the seismic vulnerability of the Kaisariani Monastery, a byzantine church that was built in Athens, Greece, at the end of the 11th to the beginning of the 12th century. Useful conclusions are drawn regarding the effectiveness of the intervention techniques used for the reduction of the vulnerability of the case-study structure, by means of comparison of the results obtained.
Application of Ionic Liquids to Energy Storage and Conversion Materials and Devices.
Watanabe, Masayoshi; Thomas, Morgan L; Zhang, Shiguo; Ueno, Kazuhide; Yasuda, Tomohiro; Dokko, Kaoru
2017-05-24
Ionic liquids (ILs) are liquids consisting entirely of ions and can be further defined as molten salts having melting points lower than 100 °C. One of the most important research areas for IL utilization is undoubtedly their energy application, especially for energy storage and conversion materials and devices, because there is a continuously increasing demand for clean and sustainable energy. In this article, various application of ILs are reviewed by focusing on their use as electrolyte materials for Li/Na ion batteries, Li-sulfur batteries, Li-oxygen batteries, and nonhumidified fuel cells and as carbon precursors for electrode catalysts of fuel cells and electrode materials for batteries and supercapacitors. Due to their characteristic properties such as nonvolatility, high thermal stability, and high ionic conductivity, ILs appear to meet the rigorous demands/criteria of these various applications. However, for further development, specific applications for which these characteristic properties become unique (i.e., not easily achieved by other materials) must be explored. Thus, through strong demands for research and consideration of ILs unique properties, we will be able to identify indispensable applications for ILs.
DOT National Transportation Integrated Search
2017-07-26
The datasets in this zip file are in support of FHWA-JPO-16-379, Analysis, Modeling, and Simulation (AMS) Testbed Development and Evaluation to Support Dynamic Mobility Applications (DMA) and Active Transportation and Demand Management (ATDM) Program...
NASA Astrophysics Data System (ADS)
Zhang, Lei; Cao, Wei; Li, Shengcai; Lu, Peng
2018-01-01
Introduced some unmanned vehicles development present situation, points out that the main development trend of photoelectric technology, analyzes the basic ability requirement of unmanned vehicles, in the future war system demonstrates the photoelectric information transmission, battlefield situational awareness, photoelectric integrated optoelectronic technology such as against the application of the unmanned vehicles demand in the future.
DOT National Transportation Integrated Search
2017-06-26
This zip file contains files of data to support FHWA-JPO-16-370, Analysis, Modeling, and Simulation (AMS) Testbed Development and Evaluation to Support Dynamic Mobility Applications (DMA) and Active Transportation and Demand Management (ATDM) Program...
The impact of job and family demands on partner’s fatigue: A study of Japanese dual-earner parents
Shimazu, Akihito; Bakker, Arnold B.; Demerouti, Evangelia; Shimada, Kyoko; Kawakami, Norito
2017-01-01
Objectives This study of Japanese dual-earner couples examined the impact of family and job demands on one’s own and one’s partner’s fatigue as well as gender differences in these effects. Methods A total of 2,502 parents (1,251 couples) were surveyed using a self-administered questionnaire. A crossover model was tested using structural equation modeling. Results The results of structural equation modeling analyses showed that both job and family demands independently exacerbated fatigue. There was an indirect effect of job and family demands on partner fatigue through one’s own fatigue only from husbands to wives. An indirect effect of job demands on partner fatigue through partner’s family demands was identified only from wives to husbands. Furthermore, there were gender differences in the crossover of fatigue. Conclusions This study shows that job and family demands influence family circumstances. When considering means to reduce employees’ fatigue, gender differences in the mechanism of fatigue need to be taken into account. PMID:28235008
Design Options for Multimodal Web Applications
NASA Astrophysics Data System (ADS)
Stanciulescu, Adrian; Vanderdonckt, Jean
The capabilities of multimodal applications running on the web are well de-lineated since they are mainly constrained by what their underlying standard mark up language offers, as opposed to hand-made multimodal applications. As the experience in developing such multimodal web applications is growing, the need arises to identify and define major design options of such application to pave the way to a structured development life cycle. This paper provides a design space of independent design options for multimodal web applications based on three types of modalities: graphical, vocal, tactile, and combined. On the one hand, these design options may provide designers with some explicit guidance on what to decide or not for their future user interface, while exploring various design alternatives. On the other hand, these design options have been implemented as graph transformations per-formed on a user interface model represented as a graph. Thanks to a transformation engine, it allows designers to play with the different values of each design option, to preview the results of the transformation, and to obtain the corresponding code on-demand
Recent advances in AM OLED technologies for application to aerospace and military systems
NASA Astrophysics Data System (ADS)
Sarma, Kalluri R.; Roush, Jerry; Chanley, Charles
2012-06-01
While initial AM OLED products have been introduced in the market about a decade ago, truly successful commercialization of OLEDs has started only a couple of years ago, by Samsung Mobile Display (SMD), with small high performance displays for smart phone applications. This success by Samsung has catalyzed significant interest in AM OLED technology advancement and commercialization by other display manufacturers. Currently, significant manufacturing capacity for AM OLED displays is being established by the industry to serve the growing demand for these displays. The current development in the AM OLED industry are now focused on the development and commercialization of medium size (~10") AM OLED panels for Tablet PC applications and large size (~55") panels for TV applications. This significant progress in commercialization of AM OLED technology is enabled by major advances in various enabling technologies that include TFT backplanes, OLED materials and device structures and manufacturing know-how. In this paper we will discuss these recent advances, particularly as they relate to supporting high performance applications such as aerospace and military systems, and then discuss the results of the OLED testing for aerospace applications.
Progress and Prospects in Stretchable Electroluminescent Devices
NASA Astrophysics Data System (ADS)
Wang, Jiangxin; Lee, Pooi See
2017-03-01
Stretchable electroluminescent (EL) devices are a new form of mechanically deformable electronics that are gaining increasing interests and believed to be one of the essential technologies for next generation lighting and display applications. Apart from the simple bending capability in flexible EL devices, the stretchable EL devices are required to withstand larger mechanical deformations and accommodate stretching strain beyond 10%. The excellent mechanical conformability in these devices enables their applications in rigorous mechanical conditions such as flexing, twisting, stretching, and folding.The stretchable EL devices can be conformably wrapped onto arbitrary curvilinear surface and respond seamlessly to the external or internal forces, leading to unprecedented applications that cannot be addressed with conventional technologies. For example, they are in demand for wide applications in biomedical-related devices or sensors and soft interactive display systems, including activating devices for photosensitive drug, imaging apparatus for internal tissues, electronic skins, interactive input and output devices, robotics, and volumetric displays. With increasingly stringent demand on the mechanical requirements, the fabrication of stretchable EL device is encountering many challenges that are difficult to resolve. In this review, recent progresses in the stretchable EL devices are covered with a focus on the approaches that are adopted to tackle materials and process challenges in stretchable EL devices and delineate the strategies in stretchable electronics. We first introduce the emission mechanisms that have been successfully demonstrated on stretchable EL devices. Limitations and advantages of the different mechanisms for stretchable EL devices are also discussed. Representative reports are reviewed based on different structural and material strategies. Unprecedented applications that have been enabled by the stretchable EL devices are reviewed. Finally, we summarize with our perspectives on the approaches for the stretchable EL devices and our proposals on the future development in these devices.
28 CFR 0.177a - Antitrust civil investigative demands.
Code of Federal Regulations, 2010 CFR
2010-07-01
... JUSTICE Assigning Responsibility Concerning Applications for Orders Compelling Testimony or Production of..., United States Code, to compel testimony in response to antitrust civil investigative demands for oral...
Adelman, Ron A.; Nwanze, Chukwuemeka C.
2011-01-01
Purpose To develop a help-wanted index (HWI) to measure trends in marketplace demand for ophthalmologists, to identify the economic drivers of demand, and to determine the impact of economic recessions on the ophthalmology job market. Methods Review of physician recruitment advertisements appearing in the journals Ophthalmology, American Journal of Ophthalmology, and Archives of Ophthalmology from January 1980 through June 2006. Results Over the 26-year study period a consistent increase in the demand for subspecialists (31% of HWI in 1980 to 80% in 2005) was noted. There was also an increase in the demand for academic ophthalmologists. The need for academic ophthalmologists seems to be correlated with national research expenditure and stock market gains (P = .00191), whereas demand for private practice ophthalmologists seems to be correlated with the national economic well-being, as measured by gross domestic product (GDP) (P < .001). Residency applicants (P = .0128) and fellowship applicants (P = .0198) respond to marketplace demand. During the recessions, the demand for ophthalmologists fell 2 to 3 years after the economic downturn. Conclusions Over a 26-year period, HWI data suggest an increased need for subspecialists and academic ophthalmologists. The ophthalmic community has been quick to respond to marketplace demand. National research expenditure, stock market gains, GDP, and discretionary health care expenditure have been associated with the ophthalmology job market. These factors tend to decline with economic recessions. Historically, the demand for ophthalmologists has declined 2 to 3 years following a recession, which may mean lower demand in the near future, given the recent recession. PMID:22253483
Adelman, Ron A; Nwanze, Chukwuemeka C
2011-12-01
To develop a help-wanted index (HWI) to measure trends in marketplace demand for ophthalmologists, to identify the economic drivers of demand, and to determine the impact of economic recessions on the ophthalmology job market. Review of physician recruitment advertisements appearing in the journals Ophthalmology, American Journal of Ophthalmology, and Archives of Ophthalmology from January 1980 through June 2006. Over the 26-year study period a consistent increase in the demand for subspecialists (31% of HWI in 1980 to 80% in 2005) was noted. There was also an increase in the demand for academic ophthalmologists. The need for academic ophthalmologists seems to be correlated with national research expenditure and stock market gains (P = .00191), whereas demand for private practice ophthalmologists seems to be correlated with the national economic well-being, as measured by gross domestic product (GDP) (P < .001). Residency applicants (P = .0128) and fellowship applicants (P = .0198) respond to marketplace demand. During the recessions, the demand for ophthalmologists fell 2 to 3 years after the economic downturn. Over a 26-year period, HWI data suggest an increased need for subspecialists and academic ophthalmologists. The ophthalmic community has been quick to respond to marketplace demand. National research expenditure, stock market gains, GDP, and discretionary health care expenditure have been associated with the ophthalmology job market. These factors tend to decline with economic recessions. Historically, the demand for ophthalmologists has declined 2 to 3 years following a recession, which may mean lower demand in the near future, given the recent recession.
School Burnout and Engagement in the Context of Demands-Resources Model
ERIC Educational Resources Information Center
Salmela-Aro, Katariina; Upadyaya, Katja
2014-01-01
Background: A four-wave longitudinal study tested the demands-resources model in the school context. Aim: To examine the applicability of the demands-resources to the school context. Method: Data of 1,709 adolescents were gathered, once during the transition from comprehensive to post-comprehensive education, twice during post-comprehensive…
ERIC Educational Resources Information Center
Dean, Robyn K.; Pollard, Robert Q., Jr.
2001-01-01
This article uses the framework of demand-control theory to examine the occupation of sign language interpreting. It discusses the environmental, interpersonal, and intrapersonal demands that impinge on the interpreter's decision latitude and notes the prevalence of cumulative trauma disorders, turnover, and burnout in the interpreting profession.…
10 CFR 905.15 - What are the requirements for the small customer plan alternative?
Code of Federal Regulations, 2011 CFR
2011-01-01
... all reasonable opportunities to meet future energy service requirements using demand-side management... applicable, and contact person; (ii) Type of customer; (iii) Current energy and demand profiles and data on... and demand use for end-use customers; (iv) Future energy services projections; (v) How items in...
37 CFR 1.446 - Refund of international application filing and processing fees.
Code of Federal Regulations, 2010 CFR
2010-07-01
... refund amounts of twenty-five dollars or less unless a refund is specifically requested and will not...)) will be refunded (PCT Rule 57.6) only if: (1) The Demand is withdrawn before the Demand has been sent by the International Preliminary Examining Authority to the International Bureau, or (2) The Demand...
Underreporting on the MMPI-2-RF in a high-demand police officer selection context: an illustration.
Detrick, Paul; Chibnall, John T
2014-09-01
Positive response distortion is common in the high-demand context of employment selection. This study examined positive response distortion, in the form of underreporting, on the Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF). Police officer job applicants completed the MMPI-2-RF under high-demand and low-demand conditions, once during the preemployment psychological evaluation and once without contingencies after completing the police academy. Demand-related score elevations were evident on the Uncommon Virtues (L-r) and Adjustment Validity (K-r) scales. Underreporting was evident on the Higher-Order scales Emotional/Internalizing Dysfunction and Behavioral/Externalizing Dysfunction; 5 of 9 Restructured Clinical scales; 6 of 9 Internalizing scales; 3 of 4 Externalizing scales; and 3 of 5 Personality Psychopathology 5 scales. Regression analyses indicated that L-r predicted demand-related underreporting on behavioral/externalizing scales, and K-r predicted underreporting on emotional/internalizing scales. Select scales of the MMPI-2-RF are differentially associated with different types of underreporting among police officer applicants. PsycINFO Database Record (c) 2014 APA, all rights reserved.
CCARES: A computer algorithm for the reliability analysis of laminated CMC components
NASA Technical Reports Server (NTRS)
Duffy, Stephen F.; Gyekenyesi, John P.
1993-01-01
Structural components produced from laminated CMC (ceramic matrix composite) materials are being considered for a broad range of aerospace applications that include various structural components for the national aerospace plane, the space shuttle main engine, and advanced gas turbines. Specifically, these applications include segmented engine liners, small missile engine turbine rotors, and exhaust nozzles. Use of these materials allows for improvements in fuel efficiency due to increased engine temperatures and pressures, which in turn generate more power and thrust. Furthermore, this class of materials offers significant potential for raising the thrust-to-weight ratio of gas turbine engines by tailoring directions of high specific reliability. The emerging composite systems, particularly those with silicon nitride or silicon carbide matrix, can compete with metals in many demanding applications. Laminated CMC prototypes have already demonstrated functional capabilities at temperatures approaching 1400 C, which is well beyond the operational limits of most metallic materials. Laminated CMC material systems have several mechanical characteristics which must be carefully considered in the design process. Test bed software programs are needed that incorporate stochastic design concepts that are user friendly, computationally efficient, and have flexible architectures that readily incorporate changes in design philosophy. The CCARES (Composite Ceramics Analysis and Reliability Evaluation of Structures) program is representative of an effort to fill this need. CCARES is a public domain computer algorithm, coupled to a general purpose finite element program, which predicts the fast fracture reliability of a structural component under multiaxial loading conditions.
NASA Astrophysics Data System (ADS)
Hoell, Simon; Omenzetter, Piotr
2016-04-01
Fueled by increasing demand for carbon neutral energy, erections of ever larger wind turbines (WTs), with WT blades (WTBs) with higher flexibilities and lower buckling capacities lead to increasing operation and maintenance costs. This can be counteracted with efficient structural health monitoring (SHM), which allows scheduling maintenance actions according to the structural state and preventing dramatic failures. The present study proposes a novel multi-step approach for vibration-based structural damage localization and severity estimation for application in operating WTs. First, partial autocorrelation coefficients (PACCs) are estimated from vibrational responses. Second, principal component analysis is applied to PACCs from the healthy structure in order to calculate scores. Then, the scores are ranked with respect to their ability to differentiate different damage scenarios. This ranking information is used for constructing hierarchical adaptive neuro-fuzzy inference systems (HANFISs), where cross-validation is used to identify optimal numbers of hierarchy levels. Different HANFISs are created for the purposes of structural damage localization and severity estimation. For demonstrating the applicability of the approach, experimental data are superimposed with signals from numerical simulations to account for characteristics of operational noise. For the physical experiments, a small scale WTB is excited with a domestic fan and damage scenarios are introduced non-destructively by attaching small masses. Numerical simulations are also performed for a representative fully functional small WT operating in turbulent wind. The obtained results are promising for future applications of vibration-based SHM to facilitate improved safety and reliability of WTs at lower costs.
NASA Astrophysics Data System (ADS)
Leong, W. K.; Lai, S. H.
2017-06-01
Due to the effects of climate change and the increasing demand on water, sustainable development in term of water resources management has become a major challenge. In this context, the application of simulation models is useful to duel with the uncertainty and complexity of water system by providing stakeholders with the best solution. This paper outlines an integrated management planning network is developed based on Water Evaluation and Planning (WEAP) to evaluate current and future water management system of Langat River Basin, Malaysia under various scenarios. The WEAP model is known as an integrated decision support system investigate major stresses on demand and supply in terms of water availability in catchment scale. In fact, WEAP is applicable to simulate complex systems including various sectors within a single catchment or transboundary river system. To construct the model, by taking account of the Langat catchment and the corresponding demand points, we defined the hydrological model into 10 sub-hydrological catchments and 17 demand points included the export of treated water to the major cities outside the catchment. The model is calibrated and verified by several quantitative statistics (coefficient of determination, R2; Nash-Sutcliffe efficiency, NSE and Percent bias, PBIAS). The trend of supply and demand in the catchment is evaluated under three scenarios to 2050, 1: Population growth rate, 2: Demand side management (DSM) and 3: Combination of DSM and reduce non-revenue water (NRW). Results show that by reducing NRW and proper DSM, unmet demand able to reduce significantly.
Kumar, Vikas; Del Vasto-Terrientes, Luis; Valls, Aida; Schuhmacher, Marta
2016-01-01
The regional water allocation planning is one of those complex decision problems where holistic approach to water supply management considering different criteria would be valuable. However, multi-criteria decision making with diverse indicators measured on different scales and uncertainty levels is difficult to solve. Objective of this paper is to develop scenarios for the future imbalances in water supply and demand for a water stressed Mediterranean area of Northern Spain (Tarragona) and to test the applicability and suitability of an outranking method ELECTRE-III-H for evaluating sectoral water allocation policies. This study is focused on the use of alternative water supply scenarios to fulfil the demand of water from three major sectors: domestic, industrial and agricultural. A detail scenario planning for regional water demand and supply has been discussed. For each future scenario of climate change, the goal is to obtain a ranking of a set of possible actions with regards to different types of indicators (costs, water stress and environmental impact). The analytical method used is based on outranking models for decision aid with hierarchical structures of criteria and ranking alternatives using partial preorders based on pairwise preference relations. We compare several adaptation measures including alternative water sources (reclaimed water and desalination); inter basin water transfer and sectoral demand management coming from industry, agriculture and domestic sectors and tested the sustainability of management actions for different climate change scenarios. Results have shown use of alternative water resources as the most reliable alternative with medium reclaimed water reuse in industry and agriculture and low to medium use of desalination water in domestic and industrial sectors as the best alternative. The proposed method has several advantages such as the management of heterogeneous scales of measurement without requiring any artificial transformation and the management of uncertainty by means of comparisons at a qualitative level in terms of the decision maker preferences. Copyright © 2015 Elsevier B.V. All rights reserved.
Probabilistic seismic demand analysis using advanced ground motion intensity measures
Tothong, P.; Luco, N.
2007-01-01
One of the objectives in performance-based earthquake engineering is to quantify the seismic reliability of a structure at a site. For that purpose, probabilistic seismic demand analysis (PSDA) is used as a tool to estimate the mean annual frequency of exceeding a specified value of a structural demand parameter (e.g. interstorey drift). This paper compares and contrasts the use, in PSDA, of certain advanced scalar versus vector and conventional scalar ground motion intensity measures (IMs). One of the benefits of using a well-chosen IM is that more accurate evaluations of seismic performance are achieved without the need to perform detailed ground motion record selection for the nonlinear dynamic structural analyses involved in PSDA (e.g. record selection with respect to seismic parameters such as earthquake magnitude, source-to-site distance, and ground motion epsilon). For structural demands that are dominated by a first mode of vibration, using inelastic spectral displacement (Sdi) can be advantageous relative to the conventionally used elastic spectral acceleration (Sa) and the vector IM consisting of Sa and epsilon (??). This paper demonstrates that this is true for ordinary and for near-source pulse-like earthquake records. The latter ground motions cannot be adequately characterized by either Sa alone or the vector of Sa and ??. For structural demands with significant higher-mode contributions (under either of the two types of ground motions), even Sdi (alone) is not sufficient, so an advanced scalar IM that additionally incorporates higher modes is used.
Characteristics of drug demand reduction structures in Britain and Iran
Narenjiha, Hooman; Noori, Roya; Ghiabi, Maziyar; Khoddami-Vishteh, Hamid-Reza
2016-01-01
Administrative structure of drug demand reduction and the way in which involved organizations interact with each other has been neglected by researchers, policy makers, and administrators at the national level and even in international institutions in this field. Studying such structures in different countries can reveal their attributes and features. In this study, key experts from the addictive behavior department of St George’s University of London and a group of Iranian specialists in the field of drug demand reduction first wrote on a sheet the name of organizations that are in charge of drug demand reduction. Then, via teamwork, they drew the connections between the organizations and compared the two charts to assess the relations between the member organizations. In total, 17 features of efficient structure were obtained as follow: multi-institutional nature, collaborative inter-institutional activities, clear and relevant inter-institutional and intra-institutional job description, the ability to share the experiences, virtual institutions activity, community-based associations activity, mutual relationships, the existence of feedback sys-tems, evaluation, changeability, the ability to collect data rapidly, being rooted in community, flexibility at the local and regional levels, connection with research centers, updated policymaking, empowering the local level, and seeking the maximum benefit and the minimum resources. Recognizing the characteristics of substance related organizations in various countries could help policy makers to improve drug demand reduction structures and to manage the wide-spread use of psychoactive substances more effectively. PMID:27853729
Characteristics of drug demand reduction structures in Britain and Iran.
Narenjiha, Hooman; Noori, Roya; Ghiabi, Maziyar; Khoddami-Vishteh, Hamid-Reza
2015-01-01
Administrative structure of drug demand reduction and the way in which involved organizations interact with each other has been neglected by researchers, policy makers, and administrators at the national level and even in international institutions in this field. Studying such structures in different countries can reveal their attributes and features. In this study, key experts from the addictive behavior department of St George's University of London and a group of Iranian specialists in the field of drug demand reduction first wrote on a sheet the name of organizations that are in charge of drug demand reduction. Then, via teamwork, they drew the connections between the organizations and compared the two charts to assess the relations between the member organizations. In total, 17 features of efficient structure were obtained as follow: multi-institutional nature, collaborative inter-institutional activities, clear and relevant inter-institutional and intra-institutional job description, the ability to share the experiences, virtual institutions activity, community-based associations activity, mutual relationships, the existence of feedback sys-tems, evaluation, changeability, the ability to collect data rapidly, being rooted in community, flexibility at the local and regional levels, connection with research centers, updated policymaking, empowering the local level, and seeking the maximum benefit and the minimum resources. Recognizing the characteristics of substance related organizations in various countries could help policy makers to improve drug demand reduction structures and to manage the wide-spread use of psychoactive substances more effectively.
Applications of three-dimensional (3D) printing for microswimmers and bio-hybrid robotics.
Stanton, M M; Trichet-Paredes, C; Sánchez, S
2015-04-07
This article will focus on recent reports that have applied three-dimensional (3D) printing for designing millimeter to micrometer architecture for robotic motility. The utilization of 3D printing has rapidly grown in applications for medical prosthetics and scaffolds for organs and tissue, but more recently has been implemented for designing mobile robotics. With an increase in the demand for devices to perform in fragile and confined biological environments, it is crucial to develop new miniaturized, biocompatible 3D systems. Fabrication of materials at different scales with different properties makes 3D printing an ideal system for creating frameworks for small-scale robotics. 3D printing has been applied for the design of externally powered, artificial microswimmers and studying their locomotive capabilities in different fluids. Printed materials have also been incorporated with motile cells for bio-hybrid robots capable of functioning by cell contraction and swimming. These 3D devices offer new methods of robotic motility for biomedical applications requiring miniature structures. Traditional 3D printing methods, where a structure is fabricated in an additive process from a digital design, and non-traditional 3D printing methods, such as lithography and molding, will be discussed.
NASA Astrophysics Data System (ADS)
Minato, Taketoshi; Abe, Takeshi
2017-12-01
The application potential of Li-ion batteries is growing as demand increases in different fields at various stages in energy systems, in addition to their conventional role as power sources for portable devices. In particular, applications in electric vehicles and renewable energy storage are increasing for Li-ion batteries. For these applications, improvements in battery performance are necessary. The Li-ion battery produces and stores electric power from the electrochemical redox reactions between the electrode materials. The interface between the electrodes and electrolyte strongly affects the battery performance because the charge transfer causing the electrode redox reaction begins at this interface. Understanding of the surface structure, electronic structure, and chemical reactions at the electrode-electrolyte interface is necessary to improve battery performance. However, the interface is located between the electrode and electrolyte materials, hindering the experimental analysis of the interface; thus, the physical properties and chemical processes have remained poorly understood until recently. Investigations of the physical properties and chemical processes at the interface have been performed using advanced surface science techniques. In this review, current knowledge and future research prospects regarding the electrode-electrolyte interface are described for the further development of Li-ion batteries.
Chemically Active, Porous 3D-Printed Thermoplastic Composites.
Evans, Kent A; Kennedy, Zachary C; Arey, Bruce W; Christ, Josef F; Schaef, Herbert T; Nune, Satish K; Erikson, Rebecca L
2018-05-02
Metal-organic frameworks (MOFs) exhibit exceptional properties and are widely investigated because of their structural and functional versatility relevant to catalysis, separations, and sensing applications. However, their commercial or large-scale application is often limited by their powder forms which make integration into devices challenging. Here, we report the production of MOF-thermoplastic polymer composites in well-defined and customizable forms and with complex internal structural features accessed via a standard three-dimensional (3D) printer. MOFs (zeolitic imidazolate framework; ZIF-8) were incorporated homogeneously into both poly(lactic acid) (PLA) and thermoplastic polyurethane (TPU) matrices at high loadings (up to 50% by mass), extruded into filaments, and utilized for on-demand access to 3D structures by fused deposition modeling. Printed, rigid PLA/MOF composites display a large surface area (SA avg = 531 m 2 g -1 ) and hierarchical pore features, whereas flexible TPU/MOF composites achieve a high surface area (SA avg = 706 m 2 g -1 ) by employing a simple method developed to expose obstructed micropores postprinting. Critically, embedded particles in the plastic matrices retain their ability to participate in chemical interactions characteristic of the parent framework. The fabrication strategies were extended to other MOFs and illustrate the potential of 3D printing to create unique porous and high surface area chemically active structures.
Trends in laser micromachining
NASA Astrophysics Data System (ADS)
Gaebler, Frank; van Nunen, Joris; Held, Andrew
2016-03-01
Laser Micromachining is well established in industry. Depending on the application lasers with pulse length from μseconds to femtoseconds and wavelengths from 1064nm and its harmonics up to 5μm or 10.6μm are used. Ultrafast laser machining using pulses with pico or femtosecond duration pulses is gaining traction, as it offers very precise processing of materials with low thermal impact. Large-scale industrial ultrafast laser applications show that the market can be divided into various sub segments. One set of applications demand low power around 10W, compact footprint and are extremely sensitive to the laser price whilst still demanding 10ps or shorter laser pulses. A second set of applications are very power hungry and only become economically feasible for large scale deployments at power levels in the 100+W class. There is also a growing demand for applications requiring fs-laser pulses. In our presentation we would like to describe these sub segments by using selected applications from the automotive and electronics industry e.g. drilling of gas/diesel injection nozzles, dicing of LED substrates. We close the presentation with an outlook to micromachining applications e.g. glass cutting and foil processing with unique new CO lasers emitting 5μm laser wavelength.
NASA Astrophysics Data System (ADS)
Sun, Qiaomei; Gu, Qilin; Zhu, Kongjun; Jin, Rongying; Liu, Jinsong; Wang, Jing; Qiu, Jinhao
2017-02-01
Dielectric materials with high permittivity are strongly demanded for various technological applications. While polarization inherently exists in ferroelectric barium titanate (BaTiO3), its high permittivity can only be achieved by chemical and/or structural modification. Here, we report the room-temperature colossal permittivity (~760,000) obtained in xNd: BaTiO3 (x = 0.5 mol%) ceramics derived from the counterpart nanoparticles followed by conventional pressureless sintering process. Through the systematic analysis of chemical composition, crystalline structure and defect chemistry, the substitution mechanism involving the occupation of Nd3+ in Ba2+ -site associated with the generation of Ba vacancies and oxygen vacancies for charge compensation has been firstly demonstrated. The present study serves as a precedent and fundamental step toward further improvement of the permittivity of BaTiO3-based ceramics.
Sun, Qiaomei; Gu, Qilin; Zhu, Kongjun; Jin, Rongying; Liu, Jinsong; Wang, Jing; Qiu, Jinhao
2017-02-13
Dielectric materials with high permittivity are strongly demanded for various technological applications. While polarization inherently exists in ferroelectric barium titanate (BaTiO 3 ), its high permittivity can only be achieved by chemical and/or structural modification. Here, we report the room-temperature colossal permittivity (~760,000) obtained in xNd: BaTiO 3 (x = 0.5 mol%) ceramics derived from the counterpart nanoparticles followed by conventional pressureless sintering process. Through the systematic analysis of chemical composition, crystalline structure and defect chemistry, the substitution mechanism involving the occupation of Nd 3+ in Ba 2+ -site associated with the generation of Ba vacancies and oxygen vacancies for charge compensation has been firstly demonstrated. The present study serves as a precedent and fundamental step toward further improvement of the permittivity of BaTiO 3 -based ceramics.
Rapid fabrication of hierarchically structured supramolecular nanocomposite thin films in one minute
Xu, Ting; Kao, Joseph
2016-11-08
Functional nanocomposites containing nanoparticles of different chemical compositions may exhibit new properties to meet demands for advanced technology. It is imperative to simultaneously achieve hierarchical structural control and to develop rapid, scalable fabrication to minimize degradation of nanoparticle properties and for compatibility with nanomanufacturing. The assembly kinetics of supramolecular nanocomposite in thin films is governed by the energetic cost arising from defects, the chain mobility, and the activation energy for inter-domain diffusion. By optimizing only one parameter, the solvent fraction in the film, the assembly kinetics can be precisely tailored to produce hierarchically structured thin films of supramolecular nanocomposites in approximately one minute. Moreover, the strong wavelength dependent optical anisotropy in the nanocomposite highlights their potential applications for light manipulation and information transmission. The present invention opens a new avenue in designing manufacture-friendly continuous processing for the fabrication of functional nanocomposite thin films.
Sun, Qiaomei; Gu, Qilin; Zhu, Kongjun; Jin, Rongying; Liu, Jinsong; Wang, Jing; Qiu, Jinhao
2017-01-01
Dielectric materials with high permittivity are strongly demanded for various technological applications. While polarization inherently exists in ferroelectric barium titanate (BaTiO3), its high permittivity can only be achieved by chemical and/or structural modification. Here, we report the room-temperature colossal permittivity (~760,000) obtained in xNd: BaTiO3 (x = 0.5 mol%) ceramics derived from the counterpart nanoparticles followed by conventional pressureless sintering process. Through the systematic analysis of chemical composition, crystalline structure and defect chemistry, the substitution mechanism involving the occupation of Nd3+ in Ba2+ -site associated with the generation of Ba vacancies and oxygen vacancies for charge compensation has been firstly demonstrated. The present study serves as a precedent and fundamental step toward further improvement of the permittivity of BaTiO3-based ceramics. PMID:28205559
Liu, Jun; Gong, Yuanyuan; Xu, Guizhou; Peng, Guo; Shah, Ishfaq Ahmad; Ul Hassan, Najam; Xu, Feng
2016-03-16
The magnetostructural coupling between structural and magnetic transitions leads to magneto-multifunctionalities of phase-transition alloys. Due to the increasing demands of multifunctional applications, to search for the new materials with tunable magnetostructural transformations in a large operating temperature range is important. In this work, we demonstrate that by chemically alloying MnNiSi with CoNiGe, the structural transformation temperature of MnNiSi (1200 K) is remarkably decreased by almost 1000 K. A tunable magnetostructural transformation between the paramagnetic hexagonal and ferromagnetic orthorhombic phase over a wide temperature window from 425 to 125 K is realized in (MnNiSi)1-x(CoNiGe)x system. The magnetic-field-induced magnetostructural transformation is accompanied by the high-performance magnetocaloric effect, proving that MnNiSi-CoNiGe system is a promising candidate for magnetic cooling refrigerant.
NASA Astrophysics Data System (ADS)
Palagi, Stefano; Mark, Andrew G.; Reigh, Shang Yik; Melde, Kai; Qiu, Tian; Zeng, Hao; Parmeggiani, Camilla; Martella, Daniele; Sanchez-Castillo, Alberto; Kapernaum, Nadia; Giesselmann, Frank; Wiersma, Diederik S.; Lauga, Eric; Fischer, Peer
2016-06-01
Microorganisms move in challenging environments by periodic changes in body shape. In contrast, current artificial microrobots cannot actively deform, exhibiting at best passive bending under external fields. Here, by taking advantage of the wireless, scalable and spatiotemporally selective capabilities that light allows, we show that soft microrobots consisting of photoactive liquid-crystal elastomers can be driven by structured monochromatic light to perform sophisticated biomimetic motions. We realize continuum yet selectively addressable artificial microswimmers that generate travelling-wave motions to self-propel without external forces or torques, as well as microrobots capable of versatile locomotion behaviours on demand. Both theoretical predictions and experimental results confirm that multiple gaits, mimicking either symplectic or antiplectic metachrony of ciliate protozoa, can be achieved with single microswimmers. The principle of using structured light can be extended to other applications that require microscale actuation with sophisticated spatiotemporal coordination for advanced microrobotic technologies.
A Review: Fundamental Aspects of Silicate Mesoporous Materials
ALOthman, Zeid A.
2012-01-01
Silicate mesoporous materials have received widespread interest because of their potential applications as supports for catalysis, separation, selective adsorption, novel functional materials, and use as hosts to confine guest molecules, due to their extremely high surface areas combined with large and uniform pore sizes. Over time a constant demand has developed for larger pores with well-defined pore structures. Silicate materials, with well-defined pore sizes of about 2.0–10.0 nm, surpass the pore-size constraint (<2.0 nm) of microporous zeolites. They also possess extremely high surface areas (>700 m2 g−1) and narrow pore size distributions. Instead of using small organic molecules as templating compounds, as in the case of zeolites, long chain surfactant molecules were employed as the structure-directing agent during the synthesis of these highly ordered materials. The structure, composition, and pore size of these materials can be tailored during synthesis by variation of the reactant stoichiometry, the nature of the surfactant molecule, the auxiliary chemicals, the reaction conditions, or by post-synthesis functionalization techniques. This review focuses mainly on a concise overview of silicate mesoporous materials together with their applications. Perusal of the review will enable researchers to obtain succinct information about microporous and mesoporous materials.
NASA Astrophysics Data System (ADS)
Hofbauer, Peter; Krödel, Matthias R.
2010-07-01
Today's space applications increasingly utilize lightweighted construction concepts, motivated by the demands of manufacturing and functionality, and by economics. Particularly for space optics, mirror stability and stiffness need to be maximized, while mass needs to be minimized. Therefore, mirror materials must possess, besides high material strength and manufacturing versatility, high thermal conductivity combined with low heat capacity and long-term stability against varying thermal loads. Additionally, optical surfaces need to be compatible with reflective coating materials. In order to achieve these requirements, the interplay between material properties and mirror design on one hand, and budgetary constraints on the other must be considered. In this paper, we address these issues by presenting an FEM design study of open and closed-back mirror structures with extremely thin reinforcing ribs, with the goal of obtaining optimal physical and optical characteristics. Furthermore, we show that ECM's carbon-fiber reinforced SiC composite, Cesic®, and its newly developed, HB-Cesic® , with their low CTE, low density, and high stiffness, are not only excellent mirror materials, but allow the rapid manufacturing of complex monolithic optical structures at reasonable cost.
Pulsed Eddy Current Sensing for Critical Pipe Condition Assessment
2017-01-01
Pulsed Eddy Current (PEC) sensing is used for Non-Destructive Evaluation (NDE) of the structural integrity of metallic structures in the aircraft, railway, oil and gas sectors. Urban water utilities also have extensive large ferromagnetic structures in the form of critical pressure pipe systems made of grey cast iron, ductile cast iron and mild steel. The associated material properties render NDE of these pipes by means of electromagnetic sensing a necessity. In recent years PEC sensing has established itself as a state-of-the-art NDE technique in the critical water pipe sector. This paper presents advancements to PEC inspection in view of the specific information demanded from water utilities along with the challenges encountered in this sector. Operating principles of the sensor architecture suitable for application on critical pipes are presented with the associated sensor design and calibration strategy. A Gaussian process-based approach is applied to model a functional relationship between a PEC signal feature and critical pipe wall thickness. A case study demonstrates the sensor’s behaviour on a grey cast iron pipe and discusses the implications of the observed results and challenges relating to this application. PMID:28954392
Navigating through the Jungle of Allergens: Features and Applications of Allergen Databases.
Radauer, Christian
2017-01-01
The increasing number of available data on allergenic proteins demanded the establishment of structured, freely accessible allergen databases. In this review article, features and applications of 6 of the most widely used allergen databases are discussed. The WHO/IUIS Allergen Nomenclature Database is the official resource of allergen designations. Allergome is the most comprehensive collection of data on allergens and allergen sources. AllergenOnline is aimed at providing a peer-reviewed database of allergen sequences for prediction of allergenicity of proteins, such as those planned to be inserted into genetically modified crops. The Structural Database of Allergenic Proteins (SDAP) provides a database of allergen sequences, structures, and epitopes linked to bioinformatics tools for sequence analysis and comparison. The Immune Epitope Database (IEDB) is the largest repository of T-cell, B-cell, and major histocompatibility complex protein epitopes including epitopes of allergens. AllFam classifies allergens into families of evolutionarily related proteins using definitions from the Pfam protein family database. These databases contain mostly overlapping data, but also show differences in terms of their targeted users, the criteria for including allergens, data shown for each allergen, and the availability of bioinformatics tools. © 2017 S. Karger AG, Basel.
Laser hybrid joining of plastic and metal components for lightweight components
NASA Astrophysics Data System (ADS)
Rauschenberger, J.; Cenigaonaindia, A.; Keseberg, J.; Vogler, D.; Gubler, U.; Liébana, F.
2015-03-01
Plastic-metal hybrids are replacing all-metal structures in the automotive, aerospace and other industries at an accelerated rate. The trend towards lightweight construction increasingly demands the usage of polymer components in drive trains, car bodies, gaskets and other applications. However, laser joining of polymers to metals presents significantly greater challenges compared with standard welding processes. We present recent advances in laser hybrid joining processes. Firstly, several metal pre-structuring methods, including selective laser melting (SLM) are characterized and their ability to provide undercut structures in the metal assessed. Secondly, process parameter ranges for hybrid joining of a number of metals (steel, stainless steel, etc.) and polymers (MABS, PA6.6-GF35, PC, PP) are given. Both transmission and direct laser joining processes are presented. Optical heads and clamping devices specifically tailored to the hybrid joining process are introduced. Extensive lap-shear test results are shown that demonstrate that joint strengths exceeding the base material strength (cohesive failure) can be reached with metal-polymer joining. Weathering test series prove that such joints are able to withstand environmental influences typical in targeted fields of application. The obtained results pave the way toward implementing metalpolymer joints in manufacturing processes.
Fan, Peixun; Wu, Hui; Zhong, Minlin; Zhang, Hongjun; Bai, Benfeng; Jin, Guofan
2016-08-14
Efficient solar energy harvesting and photothermal conversion have essential importance for many practical applications. Here, we present a laser-induced cauliflower-shaped hierarchical surface nanostructure on a copper surface, which exhibits extremely high omnidirectional absorption efficiency over a broad electromagnetic spectral range from the UV to the near-infrared region. The measured average hemispherical absorptance is as high as 98% within the wavelength range of 200-800 nm, and the angle dependent specular reflectance stays below 0.1% within the 0-60° incident angle. Such a structured copper surface can exhibit an apparent heating up effect under the sunlight illumination. In the experiment of evaporating water, the structured surface yields an overall photothermal conversion efficiency over 60% under an illuminating solar power density of ∼1 kW m(-2). The presented technology provides a cost-effective, reliable, and simple way for realizing broadband omnidirectional light absorptive metal surfaces for efficient solar energy harvesting and utilization, which is highly demanded in various light harvesting, anti-reflection, and photothermal conversion applications. Since the structure is directly formed by femtosecond laser writing, it is quite suitable for mass production and can be easily extended to a large surface area.
Tailoring structure and technological properties of plant proteins using high hydrostatic pressure.
Queirós, Rui P; Saraiva, Jorge A; da Silva, José A Lopes
2018-06-13
The demand for proteins is rising and alternatives to meat proteins are necessary since animal husbandry is expensive and intensive to the environment. Plant proteins appear as an alternative; however, their techno-functional properties need improvement. High-pressure processing (HPP) is a non-thermal technology that has several applications including the modification of proteins. The application of pressure allows modifying proteins' structure hence allowing to change several of their properties, such as hydration, hydrophobicity, and hydrophilicity. These properties may influence the solubility of proteins and their ability to stabilize emulsions or foams, create aggregates or gels, and their general role in stability and texture of food commodities. Commonly HPP decreases the proteins' solubility yet increasing their surface hydrophobicity exposing sulfhydryl groups, which promotes aggregation or gelation or enhance their ability to stabilize emulsions/foams. However, these effects are not verifiable for all the proteins and are immensely dependent on the type and concentration of the protein, environmental conditions (pH, ionic strength, and co-solutes), and HPP conditions. This review collects and critically discusses the available information on how HPP affects the structure of plant proteins and how their techno-functional properties can be tailored using this approach.
Structural and electronic properties of copper-doped chalcogenide glasses
NASA Astrophysics Data System (ADS)
Guzman, David M.; Strachan, Alejandro
2017-10-01
Using ab initio molecular dynamics based on density functional theory, we study the atomic and electronic structure, and transport properties of copper-doped germanium-based chalcogenide glasses. These mixed ionic-electronic conductor materials exhibit resistance or threshold switching under external electric field depending on slight variations of chemical composition. Understanding the origin of the transport character is essential for the functionalization of glassy chalcogenides for nanoelectronics applications. To this end, we generated atomic structures for GeX3 and GeX6 (X = S, Se, Te) at different copper concentrations and characterized the atomic origin of electronic states responsible for transport and the tendency of copper clustering as a function of metal concentration. Our results show that copper dissolution energies explain the tendency of copper to agglomerate in telluride glasses, consistent with filamentary conduction. In contrast, copper is less prone to cluster in sulfides and selenides leading to hysteresisless threshold switching where the nature of transport is dominated by electronic midgap defects derived from polar chalcogen bonds and copper atoms. Simulated I -V curves show that at least 35% by weight of copper is required to achieve the current demands of threshold-based devices for memory applications.
Jiang, Hao; Kaminska, Bozena
2018-04-24
To enable customized manufacturing of structural colors for commercial applications, up-scalable, low-cost, rapid, and versatile printing techniques are highly demanded. In this paper, we introduce a viable strategy for scaling up production of custom-input images by patterning individual structural colors on separate layers, which are then vertically stacked and recombined into full-color images. By applying this strategy on molded-ink-on-nanostructured-surface printing, we present an industry-applicable inkjet structural color printing technique termed multilayer molded-ink-on-nanostructured-surface (M-MIONS) printing, in which structural color pixels are molded on multiple layers of nanostructured surfaces. Transparent colorless titanium dioxide nanoparticles were inkjet-printed onto three separate transparent polymer substrates, and each substrate surface has one specific subwavelength grating pattern for molding the deposited nanoparticles into structural color pixels of red, green, or blue primary color. After index-matching lamination, the three layers were vertically stacked and bonded to display a color image. Each primary color can be printed into a range of different shades controlled through a half-tone process, and full colors were achieved by mixing primary colors from three layers. In our experiments, an image size as big as 10 cm by 10 cm was effortlessly achieved, and even larger images can potentially be printed on recombined grating surfaces. In one application example, the M-MIONS technique was used for printing customizable transparent color optical variable devices for protecting personalized security documents. In another example, a transparent diffractive color image printed with the M-MIONS technique was pasted onto a transparent panel for overlaying colorful information onto one's view of reality.
Metrology of deep trench etched memory structures using 3D scatterometry
NASA Astrophysics Data System (ADS)
Reinig, Peter; Dost, Rene; Moert, Manfred; Hingst, Thomas; Mantz, Ulrich; Moffitt, Jasen; Shakya, Sushil; Raymond, Christopher J.; Littau, Mike
2005-05-01
Scatterometry is receiving considerable attention as an emerging optical metrology in the silicon industry. One area of progress in deploying these powerful measurements in process control is performing measurements on real device structures, as opposed to limiting scatterometry measurements to periodic structures, such as line-space gratings, placed in the wafer scribe. In this work we will discuss applications of 3D scatterometry to the measurement of advanced trench memory devices. This is a challenging and complex scatterometry application that requires exceptionally high-performance computational abilities. In order to represent the physical device, the relatively tall structures require a high number of slices in the rigorous coupled wave analysis (RCWA) theoretical model. This is complicated further by the presence of an amorphous silicon hard mask on the surface, which is highly sensitive to reflectance scattering and therefore needs to be modeled in detail. The overall structure is comprised of several layers, with the trenches presenting a complex bow-shape sidewall that must be measured. Finally, the double periodicity in the structures demands significantly greater computational capabilities. Our results demonstrate that angular scatterometry is sensitive to the key parameters of interest. The influence of further model parameters and parameter cross correlations have to be carefully taken into account. Profile results obtained by non-library optimization methods compare favorably with cross-section SEM images. Generating a model library suitable for process control, which is preferred for precision, presents numerical throughput challenges. Details will be discussed regarding library generation approaches and strategies for reducing the numerical overhead. Scatterometry and SEM results will be compared, leading to conclusions about the feasibility of this advanced application.
1981-01-01
on modeling the managerial aspects of the firm. The second has been the application to economic theory led by ...individual portfolio optimization problems which were embedded in a larger global optimization problem. In the global problem, portfolios were linked by market ...demand quantities or be given by linear demand relationships. As in~ the source markets , the model
NASA Technical Reports Server (NTRS)
Andrews, J.
1976-01-01
The improved model is suitable for the study of benefits of worldwide information on a variety of crops. Application to the previously studied case of worldwide wheat production shows that about $108 million per year of distribution benefits to the United States would be achieved by a satellite-based wheat information system meeting the goals of LACIE. The model also indicates that improved information alone will not change world stock levels unless production itself is stabilized. The United States benefits mentioned above are associated with the reduction of price fluctuations within the year and the more effective use of international trade to balance supply and demand. Price fluctuations from year to year would be reduced only if production variability were itself reduced.
Miernik, A; Becker, C; Wullich, B; Schoenthaler, M; Arnolds, B J; Wetterauer, U
2015-01-01
The innovative power in medical engineering and technology development requires a close cooperation between universities and non-university research institutions and a collaboration with industrial partners. German knowledge in the fields of video and micro-optics, microsystem technology and of informational technology and software applications seem to be highly competitive at international level. Germany's previous leadership in the development of technical equipment will be challenged by today's requirements and difficulties in medical engineering. Research and expenses demands for the development of novel medical instruments, products and applications will increase continuously. Transparency and coordinated collaboration between universities and industrial partners will contribute to a substantial improvement in surgical therapy. Medical technology of the future, including urotechnology, requires professional structures and coordination and will have to be based on evidence.
Use of structured surfaces for friction and wear control on bearing surfaces
NASA Astrophysics Data System (ADS)
Wang, Ling
2014-10-01
Surface texturing with purposely made regular micropatterns on flat or curved surfaces, as opposed to random roughness inherited from machining processes, has attracted significant attention in recent years. At the 2013 World Tribology Congress in Turin alone there were over 40 presentations related to surface texturing for tribological applications, from magnetic hard discs and hydrodynamic bearings to artificial joints. Although surface texturing has been reported being successfully applied in industrial applications such as seals, pistons, and thrust pad bearings, the demand for robust design is still high. Etsion has recently reviewed the modeling research mainly conducted by his group Etsion I (2013 Friction 1 195-209). This paper aims to review the state-of-the-art development of surface texturing made by a wider range of researchers.
How to introduce demand side resources in the design of low-carbon power systems in China
NASA Astrophysics Data System (ADS)
Zhou, Pengcheng; Liu, Yiqun; Zeng, Ming; Sun, Chenjun
2018-04-01
Nowadays, China's energy demand sustained rapid growth, and the coal-based energy structure has adverse effects on the environment. The flexibility of demand side resource (DSR) will be greatly improved, and DSR can reduce electricity consumption actively and temporarily, and realize energy saving and emission reduction. But there are still some problems to introduce DSR in China. This paper proposes three practices for introducing demand side resources to improve the flexibility of power systems through demand resources.
The job demands-resources model of burnout.
Demerouti, E; Bakker, A B; Nachreiner, F; Schaufeli, W B
2001-06-01
The job demands-resources (JD-R) model proposes that working conditions can be categorized into 2 broad categories, job demands and job resources. that are differentially related to specific outcomes. A series of LISREL analyses using self-reports as well as observer ratings of the working conditions provided strong evidence for the JD-R model: Job demands are primarily related to the exhaustion component of burnout, whereas (lack of) job resources are primarily related to disengagement. Highly similar patterns were observed in each of 3 occupational groups: human services, industry, and transport (total N = 374). In addition, results confirmed the 2-factor structure (exhaustion and disengagement) of a new burnout instrument--the Oldenburg Burnout Inventory--and suggested that this structure is essentially invariant across occupational groups.
Identification of Conserved Water Sites in Protein Structures for Drug Design.
Jukič, Marko; Konc, Janez; Gobec, Stanislav; Janežič, Dušanka
2017-12-26
Identification of conserved waters in protein structures is a challenging task with applications in molecular docking and protein stability prediction. As an alternative to computationally demanding simulations of proteins in water, experimental cocrystallized waters in the Protein Data Bank (PDB) in combination with a local structure alignment algorithm can be used for reliable prediction of conserved water sites. We developed the ProBiS H2O approach based on the previously developed ProBiS algorithm, which enables identification of conserved water sites in proteins using experimental protein structures from the PDB or a set of custom protein structures available to the user. With a protein structure, a binding site, or an individual water molecule as a query, ProBiS H2O collects similar proteins from the PDB and performs local or binding site-specific superimpositions of the query structure with similar proteins using the ProBiS algorithm. It collects the experimental water molecules from the similar proteins and transposes them to the query protein. Transposed waters are clustered by their mutual proximity, which enables identification of discrete sites in the query protein with high water conservation. ProBiS H2O is a robust and fast new approach that uses existing experimental structural data to identify conserved water sites on the interfaces of protein complexes, for example protein-small molecule interfaces, and elsewhere on the protein structures. It has been successfully validated in several reported proteins in which conserved water molecules were found to play an important role in ligand binding with applications in drug design.
Amp: A modular approach to machine learning in atomistic simulations
NASA Astrophysics Data System (ADS)
Khorshidi, Alireza; Peterson, Andrew A.
2016-10-01
Electronic structure calculations, such as those employing Kohn-Sham density functional theory or ab initio wavefunction theories, have allowed for atomistic-level understandings of a wide variety of phenomena and properties of matter at small scales. However, the computational cost of electronic structure methods drastically increases with length and time scales, which makes these methods difficult for long time-scale molecular dynamics simulations or large-sized systems. Machine-learning techniques can provide accurate potentials that can match the quality of electronic structure calculations, provided sufficient training data. These potentials can then be used to rapidly simulate large and long time-scale phenomena at similar quality to the parent electronic structure approach. Machine-learning potentials usually take a bias-free mathematical form and can be readily developed for a wide variety of systems. Electronic structure calculations have favorable properties-namely that they are noiseless and targeted training data can be produced on-demand-that make them particularly well-suited for machine learning. This paper discusses our modular approach to atomistic machine learning through the development of the open-source Atomistic Machine-learning Package (Amp), which allows for representations of both the total and atom-centered potential energy surface, in both periodic and non-periodic systems. Potentials developed through the atom-centered approach are simultaneously applicable for systems with various sizes. Interpolation can be enhanced by introducing custom descriptors of the local environment. We demonstrate this in the current work for Gaussian-type, bispectrum, and Zernike-type descriptors. Amp has an intuitive and modular structure with an interface through the python scripting language yet has parallelizable fortran components for demanding tasks; it is designed to integrate closely with the widely used Atomic Simulation Environment (ASE), which makes it compatible with a wide variety of commercial and open-source electronic structure codes. We finally demonstrate that the neural network model inside Amp can accurately interpolate electronic structure energies as well as forces of thousands of multi-species atomic systems.
Mohanty, Debasish; Li, Jianlin; Nagpure, Shrikant C; ...
2015-12-21
Materials diagnostic techniques are the principal tools used in the development of low-cost, high-performance electrodes for next-generation lithium-based energy storage technologies. Also, this review highlights the importance of materials diagnostic techniques in unraveling the structure and the structural degradation mechanisms in high-voltage, high-capacity oxides that have the potential to be implemented in high-energy-density lithium-ion batteries for transportation that can use renewable energy and is less-polluting than today. The rise in CO 2 concentration in the earth’s atmosphere due to the use of petroleum products in vehicles and the dramatic increase in the cost of gasoline demand the replacement of currentmore » internal combustion engines in our vehicles with environmentally friendly, carbon free systems. Therefore, vehicles powered fully/partially by electricity are being introduced into today’s transportation fleet. As power requirements in all-electric vehicles become more demanding, lithium-ion battery (LiB) technology is now the potential candidate to provide higher energy density. Moreover, discovery of layered high-voltage lithium-manganese–rich (HV-LMR) oxides has provided a new direction toward developing high-energy-density LiBs because of their ability to deliver high capacity (~250 mA h/g) and to be operated at high operating voltage (~4.7 V). Unfortunately, practical use of HV-LMR electrodes is not viable because of structural changes in the host oxide during operation that can lead to fundamental and practical issues. This article provides the current understanding on the structure and structural degradation pathways in HV-LMR oxides, and manifests the importance of different materials diagnostic tools to unraveling the key mechanism(s). Furthermore, the fundamental insights reported, might become the tools to manipulate the chemical and/or structural aspects of HV-LMR oxides for low cost, high-energy-density LiB applications.« less
Development of zirconia based phosphors for application in lighting and as luminescent bioprobes =
NASA Astrophysics Data System (ADS)
Soares, Maria Rosa Nunes
The strong progress evidenced in photonic and optoelectronic areas, accompanied by an exponential development in the nanoscience and nanotechnology, gave rise to an increasing demand for efficient luminescent materials with more and more exigent characteristics. In this field, wide band gap hosts doped with lanthanide ions represent a class of luminescent materials with a strong technological importance. Within wide band gap material, zirconia owns a combination of physical and chemical properties that potentiate it as an excellent host for the aforementioned ions, envisaging its use in different areas, including in lighting and optical sensors applications, such as pressure sensors and biosensors. Following the demand for outstanding luminescent materials, there is also a request for fast, economic and an easy scale-up process for their production. Regarding these demands, laser floating zone, solution combustion synthesis and pulsed laser ablation in liquid techniques are explored in this thesis for the production of single crystals, nanopowders and nanoparticles of lanthanides doped zirconia based hosts. Simultaneously, a detailed study of the morphological, structural and optical properties of the produced materials is made. The luminescent characteristics of zirconia and yttria stabilized zirconia (YSZ) doped with different lanthanide ions (Ce3+ (4f1), Pr3+ (4f2), Sm3+ (4f5), Eu3+ (4f6), Tb3+ (4f8), Dy3+ (4f9), Er3+ (4f11), Tm3+ (4f12), Yb3+ (4f13)) and co-doped with Er3+,Yb3+ and Tm3+,Yb3+ are analysed. Besides the Stokes luminescence, the anti- Stokes emission upon infrared excitation (upconversion and black body radiation) is also analysed and discussed. The comparison of the luminescence characteristics in materials with different dimensions allowed to analyse the effect of size in the luminescent properties of the dopant lanthanide ions. The potentialities of application of the produced luminescent materials in solid state light, biosensors and pressure sensors are explored taking into account their studied characteristics.
Job Demands and Job Resources as Predictors of Absence Duration and Frequency.
ERIC Educational Resources Information Center
Bakker, Arnold B.; Demerouti, Evangelia; de Boer, Elpine; Schaufeli, Wilmar B.
2003-01-01
Structural equation modeling of data from 214 employees indicated that job demands uniquely predicted burnout and indirectly predicted length of absence. Job resources (physical, psychological, social, or organizational aspects that reduce job demands or stimulate growth) uniquely predicted organizational commitment and indirectly predicted spells…
ERIC Educational Resources Information Center
Suki, Norazah Mohd
2013-01-01
Purpose: The study aims to examine structural relationships of product features, brand name, product price and social influence with demand for Smartphones among Malaysian students'. Design/methodology/approach: Data collected from 320 valid pre-screened university students studying at the pubic higher learning institution in Federal Territory of…
Detrick, Paul; Chibnall, John T; Call, Cynthia
2010-09-01
Understanding and detecting response distortion is important in the high-demand circumstances of personnel selection. In this article, we describe positive response distortion on the Revised NEO Personality Inventory (NEO PI-R; Costa & McCrae, 1992) among police officer applicants under high and low demand conditions. Positive response distortion primarily reflected denial/minimization of Neuroticism and accentuation of traits associated with moralistic bias (Agreeableness and Conscientiousness). Validity of the NEO PI-R research validity scale, Positive Presentation Management, was weakly supported with respect to the Neuroticism domain only. Results will be useful in interpreting personality inventory results in the police personnel selection process.
Correlations between Energy and Displacement Demands for Performance-Based Seismic Engineering
NASA Astrophysics Data System (ADS)
Mollaioli, Fabrizio; Bruno, Silvia; Decanini, Luis; Saragoni, Rodolfo
2011-01-01
The development of a scientific framework for performance-based seismic engineering requires, among other steps, the evaluation of ground motion intensity measures at a site and the characterization of their relationship with suitable engineering demand parameters (EDPs) which describe the performance of a structure. In order to be able to predict the damage resulting from earthquake ground motions in a structural system, it is first necessary to properly identify ground motion parameters that are well correlated with structural response and, in turn, with damage. Since structural damage during an earthquake ground motion may be due to excessive deformation or to cumulative cyclic damage, reliable methods for estimating displacement demands on structures are needed. Even though the seismic performance is directly related to the global and local deformations of the structure, energy-based methodologies appear more helpful in concept, as they permit a rational assessment of the energy absorption and dissipation mechanisms that can be effectively accomplished to balance the energy imparted to the structure. Moreover, energy-based parameters are directly related to cycles of response of the structure and, therefore, they can implicitly capture the effect of ground motion duration, which is ignored by conventional spectral parameters. Therefore, the identification of reliable relationships between energy and displacement demands represents a fundamental issue in both the development of more reliable seismic code provisions and the evaluation of seismic vulnerability aimed at the upgrading of existing hazardous facilities. As these two aspects could become consistently integrated within a performance-based seismic design methodology, understanding how input and dissipated energy are correlated with displacement demands emerges as a decisive prerequisite. The aim of the present study is the establishment of functional relationships between input and dissipated energy (that can be considered as parameters representative of the amplitude, frequency content and duration of earthquake ground motions) and displacement-based response measures that are well correlated to structural and non-structural damage. For the purpose of quantifying the EDPs to be related to the energy measures, for comprehensive range of ground motion and structural characteristics, both simplified and more accurate numerical models will be used in this study for the estimation of local and global displacement and energy demands. Parametric linear and nonlinear time-history analyses will be performed on elastic and inelastic SDOF and MDOF systems, in order to assume information on the seismic response of a wide range of current structures. Hysteretic models typical of frame force/displacement behavior will be assumed for the local inelastic cyclic response of the systems. A wide range of vibration periods will be taken into account so as to define displacement, interstory drift and energy spectra for MDOF systems. Various scalar measures related to the deformation demand will be used in this research. These include the spectral displacements, the peak roof drift ratio, and the peak interstory drift ratio. A total of about 900 recorded ground motions covering a broad variety of condition in terms of frequency content, duration and amplitude will be used as input in the dynamic analyses. The records are obtained from 40 earthquakes and grouped as a function of magnitude of the event, source-to-site condition and site soil condition. In addition, in the data-set of records a considerable number of near-fault signals is included, in recognition of the particular significance of pulse-like time histories in causing large seismic demands to the structures.
Bonded repair of composite aircraft structures: A review of scientific challenges and opportunities
NASA Astrophysics Data System (ADS)
Katnam, K. B.; Da Silva, L. F. M.; Young, T. M.
2013-08-01
Advanced composite materials have gained popularity in high-performance structural designs such as aerospace applications that require lightweight components with superior mechanical properties in order to perform in demanding service conditions as well as provide energy efficiency. However, one of the major challenges that the aerospace industry faces with advanced composites - because of their inherent complex damage behaviour - is structural repair. Composite materials are primarily damaged by mechanical loads and/or environmental conditions. If material damage is not extensive, structural repair is the only feasible solution as replacing the entire component is not cost-effective in many cases. Bonded composite repairs (e.g. scarf patches) are generally preferred as they provide enhanced stress transfer mechanisms, joint efficiencies and aerodynamic performance. With an increased usage of advanced composites in primary and secondary aerospace structural components, it is thus essential to have robust, reliable and repeatable structural bonded repair procedures to restore damaged composite components. But structural bonded repairs, especially with primary structures, pose several scientific challenges with the current existing repair technologies. In this regard, the area of structural bonded repair of composites is broadly reviewed - starting from damage assessment to automation - to identify current scientific challenges and future opportunities.
Chen, Jiabo; Li, Fayun; Fan, Zhiping; Wang, Yanjie
2016-01-01
Source apportionment of river water pollution is critical in water resource management and aquatic conservation. Comprehensive application of various GIS-based multivariate statistical methods was performed to analyze datasets (2009–2011) on water quality in the Liao River system (China). Cluster analysis (CA) classified the 12 months of the year into three groups (May–October, February–April and November–January) and the 66 sampling sites into three groups (groups A, B and C) based on similarities in water quality characteristics. Discriminant analysis (DA) determined that temperature, dissolved oxygen (DO), pH, chemical oxygen demand (CODMn), 5-day biochemical oxygen demand (BOD5), NH4+–N, total phosphorus (TP) and volatile phenols were significant variables affecting temporal variations, with 81.2% correct assignments. Principal component analysis (PCA) and positive matrix factorization (PMF) identified eight potential pollution factors for each part of the data structure, explaining more than 61% of the total variance. Oxygen-consuming organics from cropland and woodland runoff were the main latent pollution factor for group A. For group B, the main pollutants were oxygen-consuming organics, oil, nutrients and fecal matter. For group C, the evaluated pollutants primarily included oxygen-consuming organics, oil and toxic organics. PMID:27775679
NASA Astrophysics Data System (ADS)
Azarbayejani, M.; Jalalpour, M.; El-Osery, A. I.; Reda Taha, M. M.
2011-08-01
In this paper, an innovative field application of a structural health monitoring (SHM) system using field programmable gate array (FPGA) technology and wireless communication is presented. The new SHM system was installed to monitor a reinforced concrete (RC) bridge on Interstate 40 (I-40) in Tucumcari, New Mexico. This newly installed system allows continuous remote monitoring of this bridge using solar power. Details of the SHM component design and installation are discussed. The integration of FPGA and solar power technologies make it possible to remotely monitor infrastructure with limited access to power. Furthermore, the use of FPGA technology enables smart monitoring where data communication takes place on-need (when damage warning signs are met) and on-demand for periodic monitoring of the bridge. Such a system enables a significant cut in communication cost and power demands which are two challenges during SHM operation. Finally, a three-dimensional finite element (FE) model of the bridge was developed and calibrated using a static loading field test. This model is then used for simulating damage occurrence on the bridge. Using the proposed automation process for SHM will reduce human intervention significantly and can save millions of dollars currently spent on prescheduled inspection of critical infrastructure worldwide.
Innovative Product Design Based on Comprehensive Customer Requirements of Different Cognitive Levels
Zhao, Wu; Zheng, Yake; Wang, Rui; Wang, Chen
2014-01-01
To improve customer satisfaction in innovative product design, a topology structure of customer requirements is established and an innovative product approach is proposed. The topology structure provides designers with reasonable guidance to capture the customer requirements comprehensively. With the aid of analytic hierarchy process (AHP), the importance of the customer requirements is evaluated. Quality function deployment (QFD) is used to translate customer requirements into product and process design demands and pick out the technical requirements which need urgent improvement. In this way, the product is developed in a more targeted way to satisfy the customers. the theory of innovative problems solving (TRIZ) is used to help designers to produce innovative solutions. Finally, a case study of automobile steering system is used to illustrate the application of the proposed approach. PMID:25013862
Li, Xiaolong; Zhao, Wu; Zheng, Yake; Wang, Rui; Wang, Chen
2014-01-01
To improve customer satisfaction in innovative product design, a topology structure of customer requirements is established and an innovative product approach is proposed. The topology structure provides designers with reasonable guidance to capture the customer requirements comprehensively. With the aid of analytic hierarchy process (AHP), the importance of the customer requirements is evaluated. Quality function deployment (QFD) is used to translate customer requirements into product and process design demands and pick out the technical requirements which need urgent improvement. In this way, the product is developed in a more targeted way to satisfy the customers. the theory of innovative problems solving (TRIZ) is used to help designers to produce innovative solutions. Finally, a case study of automobile steering system is used to illustrate the application of the proposed approach.
Conjoint Forming - Technologies for Simultaneous Forming and Joining
NASA Astrophysics Data System (ADS)
Groche, P.; Wohletz, S.; Mann, A.; Krech, M.; Monnerjahn, V.
2016-03-01
The market demand for new products optimized for e. g. lightweight applications or smart components leads to new challenges in production engineering. Hybrid structures represent one promising approach. They aim at higher product performance by using a suitable combination of different materials. The developments of hybrid structures stimulate the research on joining of dissimilar materials. Since they allow for joining dissimilar materials without external heating technologies based on joining by plastic deformation seem to be of special attractiveness. The paper at hand discusses the conjoint forming approach. This approach combines forming and joining in one process. Two or more workpieces are joined while at least one workpiece is plastically deformed. After presenting the fundamental joining mechanisms, the conjoint forming approach is discussed comprehensively. Examples of conjoint processes demonstrate the effectiveness and reveal the underlying phenomena.
Health care, human worth and the limits of the particular.
Cherry, C
1997-01-01
An ethics concerned with health care developments and systems must be historically continuous, especially as it concerns the application to managed structures of key moral-epistemic concepts such as care, love and empathy. These concepts are traditionally most at home in the personal, individual domain. Human beings have non-instrumental worth just because they are human beings and not by virtue of their capacities. Managed health care systems tend to abstract from this worth in respect of both individuals' distinctness and individual identity. The first, a common feature of quantitative approaches to health care assessment and delivery, is avoidable. The second, by contrast, is necessarily sacrificed in impersonally managed structures. Failure to distinguish the two encourages confusion and distress, and the demand for impossible medico-moral relationships. PMID:9358352
Ng, Wei Long; Goh, Min Hao; Yeong, Wai Yee; Naing, May Win
2018-02-27
Native tissues and/or organs possess complex hierarchical porous structures that confer highly-specific cellular functions. Despite advances in fabrication processes, it is still very challenging to emulate the hierarchical porous collagen architecture found in most native tissues. Hence, the ability to recreate such hierarchical porous structures would result in biomimetic tissue-engineered constructs. Here, a single-step drop-on-demand (DOD) bioprinting strategy is proposed to fabricate hierarchical porous collagen-based hydrogels. Printable macromolecule-based bio-inks (polyvinylpyrrolidone, PVP) have been developed and printed in a DOD manner to manipulate the porosity within the multi-layered collagen-based hydrogels by altering the collagen fibrillogenesis process. The experimental results have indicated that hierarchical porous collagen structures could be achieved by controlling the number of macromolecule-based bio-ink droplets printed on each printed collagen layer. This facile single-step bioprinting process could be useful for the structural design of collagen-based hydrogels for various tissue engineering applications.
NASA Astrophysics Data System (ADS)
Raad Hussein, Alaa; Badri Albarody, Thar M.; Megat Yusoff, Puteri Sri Melor Bt
2018-05-01
Nowadays there is no viable non-destructive method that could detect flaws in complex composite products. Such a method could provide unique tools to allow engineers to minimize time consumption and cost during the evaluation of various product parameters without disturbing production. The latest research and development on propagation waves introduce micro, radio and millimetre waves as new potential non-destructive test methods for evaluation of mechanical flaws and prediction of failure in a product during production. This paper focuses on recent developments, usage, classification of electromagnetic waves under the range of radio frequency, millimetre and micro-waves. In addition, this paper reviews the application of propagation wave and proposed a new health monitoring technique based on Doppler Effect for vibration measurement in complex composite structures. Doppler Effect is influenced by dynamic behaviour of the composite structures and both are effect by flaws occurred inside the structure. Composite manufacturers, especially Aerospace industry are demanding these methods comprehensively inspect and evaluate the damages and defects in their products.
Dynamic environmental control mechanisms for pneumatic foil constructions
NASA Astrophysics Data System (ADS)
Flor, Jan-Frederik; Wu, Yupeng; Beccarelli, Paolo; Chilton, John
2017-11-01
Membrane and foil structures have become over the last decades an attractive alternative to conventional materials and building systems with increasing implementation in different typologies and scale. The development of transparent, light, flexible and resistant materials like Ethylene Tetrafluoroethylene (ETFE) has triggered a rethinking of the building envelope in the building industry towards lightweight systems. ETFE foil cushions have proven to fulfil the design requirements in terms of structural efficiency and aesthetic values. But the strategies to satisfy increasing demands of energy efficiency and comfort conditions are still under development. The prediction and manipulation of the thermo-optical behaviour of ETFE foil cushion structures currently remain as one of the main challenges for designers and manufacturers. This paper reviews ongoing research regarding the control of the thermo-optical performance of ETFE cushion structures and highlights challenges and possible improvements. An overview of different dynamic and responsive environmental control mechanisms for multilayer foil constructions is provided and the state of the art in building application outlined by the discussion of case studies.
Greenwood, M J; Hunt, G L
1995-04-01
The authors use Standard Metropolitan Statistical Area (SMSA) data constructed from 1980 census microdata files and other sources to estimate a structural model of native/foreign-born labor demand and labor supply which distinguishes the effects upon real wages of each type of labor and on the employment of natives. The authors specify, econometrically estimate, and simulate the structural model which incorporates not only a production structure channel through which immigrants influence area real wages and employment, but also demand and native labor supply channels. It is noted that while these are not the only channels through which immigrants may affect native workers, the model nonetheless constitutes a step in the direction of a general equilibrium approach. In the production structure channel, immigrants and natives are found to be substitutes in production. Immigration lowers foreign-born wage rates and leads to lower wages for natives. The negative effects of the production channel usually are ameliorated through the demand channel. Further, immigrants add to local demand through their earnings and potentially through non-labor income, while also lowering unit costs and local prices which enhances real incomes and potentially net exports, and thus the demands for local output and area labor. The author discusses findings of interest from the simulation results based upon an analysis of all areas.
An entangled-light-emitting diode.
Salter, C L; Stevenson, R M; Farrer, I; Nicoll, C A; Ritchie, D A; Shields, A J
2010-06-03
An optical quantum computer, powerful enough to solve problems so far intractable using conventional digital logic, requires a large number of entangled photons. At present, entangled-light sources are optically driven with lasers, which are impractical for quantum computing owing to the bulk and complexity of the optics required for large-scale applications. Parametric down-conversion is the most widely used source of entangled light, and has been used to implement non-destructive quantum logic gates. However, these sources are Poissonian and probabilistically emit zero or multiple entangled photon pairs in most cycles, fundamentally limiting the success probability of quantum computational operations. These complications can be overcome by using an electrically driven on-demand source of entangled photon pairs, but so far such a source has not been produced. Here we report the realization of an electrically driven source of entangled photon pairs, consisting of a quantum dot embedded in a semiconductor light-emitting diode (LED) structure. We show that the device emits entangled photon pairs under d.c. and a.c. injection, the latter achieving an entanglement fidelity of up to 0.82. Entangled light with such high fidelity is sufficient for application in quantum relays, in core components of quantum computing such as teleportation, and in entanglement swapping. The a.c. operation of the entangled-light-emitting diode (ELED) indicates its potential function as an on-demand source without the need for a complicated laser driving system; consequently, the ELED is at present the best source on which to base future scalable quantum information applications.
Choi, BongKyoo; Kawakami, Norito; Chang, SeiJin; Koh, SangBaek; Bjorner, Jakob; Punnett, Laura; Karasek, Robert
2008-01-01
The five-item psychological demands scale of the Job Content Questionnaire (JCQ) has been assumed to be one-dimensional in practice. To examine whether the scale has sufficient internal consistency and external validity to be treated as a single scale, using the cross-national JCQ datasets from the United States, Korea, and Japan. Exploratory factor analyses with 22 JCQ items, confirmatory factor analyses with the five psychological demands items, and correlations analyses with mental health indexes. Generally, exploratory factor analyses displayed the predicted demand/control/support structure with three and four factors extracted. However, at more detailed levels of exploratory and confirmatory factor analyses, the demands scale showed clear evidence of multi-factor structure. The correlations of items and subscales of the demands scale with mental health indexes were similar to those of the full scale in the Korean and Japanese datasets, but not in the U.S. data. In 4 out of 16 sub-samples of the U.S. data, several significant correlations of the components of the demands scale with job dissatisfaction and life dissatisfaction were obscured by the full scale. The multidimensionality of the psychological demands scale should be considered in psychometric analysis and interpretation, occupational epidemiologic studies, and future scale extension.
Empowering leadership and job crafting: The role of employee optimism.
Thun, Sylvi; Bakker, Arnold B
2018-06-08
The objective of this study was to test the relationship between empowering leadership and job crafting and to examine the moderating role of optimism as a personal resource. We hypothesized that the association between empowering leadership and job crafting would be stronger for employees with high (vs. low) levels of optimism. A total of 331 Norwegian workers from a variety of occupations participated in our study. Results of structural equation modelling analysis generally supported our hypotheses. Empowering leadership was positively related to 3 of the 4 job crafting strategies investigated (increasing structural job resources, increasing social job resources, and increasing challenging job demands; but not reducing hindrance job demands). Moreover, as hypothesized, optimism strengthened the empowering leadership-job crafting relationship for increasing structural resources and increasing challenging demands. The results suggest that empowering leadership is an important antecedent of job crafting strategies, except for reducing hindrance demands. The implications of these findings are discussed. Copyright © 2018 John Wiley & Sons, Ltd.
Yang, Qu; Zhou, Ziyao; Wang, Liqian; Zhang, Hongjia; Cheng, Yuxin; Hu, Zhongqiang; Peng, Bin; Liu, Ming
2018-05-01
To meet the demand of developing compatible and energy-efficient flexible spintronics, voltage manipulation of magnetism on soft substrates is in demand. Here, a voltage tunable flexible field-effect transistor structure by ionic gel (IG) gating in perpendicular synthetic anti-ferromagnetic nanostructure is demonstrated. As a result, the interlayer Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction can be tuned electrically at room temperature. With a circuit gating voltage, anti-ferromagnetic (AFM) ordering is enhanced or converted into an AFM-ferromagnetic (FM) intermediate state, accompanying with the dynamic domain switching. This IG gating process can be repeated stably at different curvatures, confirming an excellent mechanical property. The IG-induced modification of interlayer exchange coupling is related to the change of Fermi level aroused by the disturbance of itinerant electrons. The voltage modulation of RKKY interaction with excellent flexibility proposes an application potential for wearable spintronic devices with energy efficiency and ultralow operation voltage. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Strategies for the design of bright upconversion nanoparticles for bioanalytical applications
NASA Astrophysics Data System (ADS)
Wiesholler, Lisa M.; Hirsch, Thomas
2018-06-01
In recent years upconversion nanoparticles (UCNPs) received great attention because of their outstanding optical properties. Especially in bioanalytical applications this class of materials can overcome limitations of common probes like high background fluorescence or blinking. Nevertheless, the requirements for UCNPs to be applicable in biological samples, e.g. small size, water-dispersibility, excitation at low power density are in contradiction with the demand of high brightness. Therefore, a lot of attention is payed to the enhancement of the upconversion luminescence. This review discuss the recent trends and strategies to boost the brightness of UCNPs, classified in three main directions: a) improving the efficiency of energy absorption by the sensitizer via coupling to plasmonic or photonic structures or via attachment of ligands for light harvesting; b) minimizing non-radiative deactivation by variations in the architecture of UCNPs; and c) changing the excitation wavelength to get bright particles at low excitation power density for applications in aqueous systems. These strategies are critically reviewed including current limitations as well as future perspectives for the design of efficient UCNPs especially for sensing application in biological samples or cells.
NASA Technical Reports Server (NTRS)
Smart, M. C.; Ratnakumar, B. V.; Whitcanack, L. D.; Chin, K. B.; Surampudi, S.; Narayanan, S. R.; Alamgir, Mohamed; Yu, Ji-Sang; Plichta, Edward P.
2004-01-01
Both NASA and the U.S. Army have interest in developing secondary energy storage devices that are capable of meeting the demanding performance requirements of aerospace and man-portable applications. In order to meet these demanding requirements, gel-polymer electrolyte-based lithium-ion cells are being actively considered, due to their promise of providing high specific energy and enhanced safety aspects.
Apparatus producing constant cable tension for intermittent demand
Lauritzen, T.
1984-05-23
This invention relates to apparatus for producing constant tension in cable or the like when it is unreeled and reeled from a drum or spool under conditions of intermittent demand. The invention is particularly applicable to the handling of superconductive cable, but the invention is also applicable to the unreeling and reeling of other strands, such as electrical cable, wire, cord, other cables, fish line, wrapping paper and numerous other materials.
NASA Astrophysics Data System (ADS)
Zhou, Qing; Wu, Feng; Zhang, Qian
Serious water scarcity, low water-use efficiency, and over-exploitation of underground water have hindered socio-economic development and led to environmental degradation in the Heihe River basin, northwestern China. Price leveraging is an important tool in water demand management, and it is considered to be effective in promoting water conservation and improving water use efficiency on the premise that water demand is elastic. In the present study, we examine whether price is an effective and applicable instrument for restraining the increasing demand for agricultural irrigation water in the middle reaches of the Heihe River basin and how will it affect farmers' decisions on irrigation and crop structure. Specifically, the price elasticity of agricultural water demand was estimated based on the irrigation water demand function. The results show that the agricultural irrigation water price is statistically significant, but its elasticity is very low under current low water price. Price leverage cannot play a significant role in the context of the current pricing regime and farmers' response to price increase is intrinsically weak. To create incentives for conserving water and improving irrigation efficiency, price mechanism should be accompanied with clearly defined and legally enforceable water rights, restricted water quota measures, and reform of water authorities and water-user associations. Furthermore, increases of surface irrigation water price may lead to the over-withdrawal of groundwater, consequently, effective groundwater licensing and levying must take place to limit the total volume of groundwater withdrawal. In all, improving irrigation efficiency through better management and the adoption of water-saving technologies is the ultimate way to deal with the challenges facing irrigated agriculture in the middle reaches of the Heihe River basin.
Rainwater harvesting systems for low demanding applications.
Sanches Fernandes, Luís F; Terêncio, Daniela P S; Pacheco, Fernando A L
2015-10-01
A rainwater harvesting system (RHS) was designed for a waste treatment facility located near the town of Mirandela (northern Portugal), to be used in the washing of vehicles and other equipment, the cleaning of outside concrete or asphalt floors, and the watering of green areas. Water tank volumes representing 100% efficiency (Vr) were calculated by the Ripple method with different results depending on two consumption scenarios adopted for irrigation. The RHS design was based on a precipitation record spanning a rather long period (3 decades). The calculated storage capacities fulfilled the water demand even when prolonged droughts occurred during that timeframe. However, because the drought events have been rather scarce the Vr values were considered oversized and replaced by optimal volumes. Notwithstanding the new volumes were solely half of the original Vr values, the projected RHS efficiency remained very high (around 90%) while the probability of system failure (efficiency<100%) stayed very low (in the order of 5%). In both scenarios, the economic savings related to the optimization of Vr were noteworthy, while the investment's return periods decreased substantially from the original to the optimized solutions. A high efficiency with a low storage capacity is typical of low demanding applications of rainwater harvesting, where water availability (Vw) largely exceeds water demand (Cw), that is to say where demand fractions (Cw/Vw) are very low. Based on the results of a literature review covering an ample geographic distribution and describing a very large number of demand fraction scenarios, a Cw/Vw=0.8 was defined as the threshold to generally distinguish the low from the high demanding RHS applications. Copyright © 2015 Elsevier B.V. All rights reserved.
Bastani, Peivand; Mehralian, Gholamhossein; Dinarvand, Rasoul
2015-01-01
Objective: The aim of this study was to review the current methods of pharmaceutical purchasing by Iranian insurance organizations within the World Bank conceptual framework model so as to provide applicable pharmaceutical resource allocation and purchasing (RAP) arrangements in Iran. Methods: This qualitative study was conducted through a qualitative document analysis (QDA), applying the four-step Scott method in document selection, and conducting 20 semi-structured interviews using a triangulation method. Furthermore, the data were analyzed applying five steps framework analysis using Atlas-ti software. Findings: The QDA showed that the purchasers face many structural, financing, payment, delivery and service procurement and purchasing challenges. Moreover, the findings of interviews are provided in three sections including demand-side, supply-side and price and incentive regime. Conclusion: Localizing RAP arrangements as a World Bank Framework in a developing country like Iran considers the following as the prerequisite for implementing strategic purchasing in pharmaceutical sector: The improvement of accessibility, subsidiary mechanisms, reimbursement of new drugs, rational use, uniform pharmacopeia, best supplier selection, reduction of induced demand and moral hazard, payment reform. It is obvious that for Iran, these customized aspects are more various and detailed than those proposed in a World Bank model for developing countries. PMID:25710045
School management and contingency theory: an emerging perspective.
Hanson, E M
1979-01-01
In an article written for educational administrators, Hanson explains the assumptions, framework, and application of contingency theory. The author sees contingency theory as a way for organizations to adapt to uncertainty by developing a strategic plan with alternative scenarios. He urges school administrators to join businessmen and public managers in using a technique described as "the most powerful current sweeping over the organizational field." The theory assumes that: (1) a maze of goals govern the development of events; (2) different management approaches may be appropriate within the same organization; and (3) different leadership styles suit different situations. Contingency planning helps the organization to respond to uncertainty in the external environment by identifying possible events that may occur and by preparing alternative stratgies to deal with them. Hanson describes the purpose of this process as providing "a more effective match between an organization and its environment." He explains that contingency theory analyzes the internal adjustments of the organization (e.g., decision making process, structure, technology, instructional techniques) as it seeks to meet the shifting demands of its external or internal environments. According to the author, the intent of contingency theory is to establish an optimal "match" between environmental demands (and support) and the response capabilities of the organization including its structure, planning process, and leadership style.
Latent factor structure of a behavioral economic marijuana demand curve.
Aston, Elizabeth R; Farris, Samantha G; MacKillop, James; Metrik, Jane
2017-08-01
Drug demand, or relative value, can be assessed via analysis of behavioral economic purchase task performance. Five demand indices are typically obtained from drug purchase tasks. The goal of this research was to determine whether metrics of marijuana reinforcement from a marijuana purchase task (MPT) exhibit a latent factor structure that efficiently characterizes marijuana demand. Participants were regular marijuana users (n = 99; 37.4% female, 71.5% marijuana use days [5 days/week], 15.2% cannabis dependent) who completed study assessments, including the MPT, during a baseline session. Principal component analysis was used to examine the latent structure underlying MPT indices. Concurrent validity was assessed via examination of relationships between latent factors and marijuana use, past quit attempts, and marijuana expectancies. A two-factor solution was confirmed as the best fitting structure, accounting for 88.5% of the overall variance. Factor 1 (65.8% variance) reflected "Persistence," indicating sensitivity to escalating marijuana price, which comprised four MPT indices (elasticity, O max , P max , and breakpoint). Factor 2 (22.7% variance) reflected "Amplitude," indicating the amount consumed at unrestricted price (intensity). Persistence factor scores were associated with fewer past marijuana quit attempts and lower expectancies of negative use outcomes. Amplitude factor scores were associated with more frequent use, dependence symptoms, craving severity, and positive marijuana outcome expectancies. Consistent with research on alcohol and cigarette purchase tasks, the MPT can be characterized with a latent two-factor structure. Thus, demand for marijuana appears to encompass distinct dimensions of price sensitivity and volumetric consumption, with differential relations to other aspects of marijuana motivation.
Policy implications of the GRI baseline projection of US energy supply and demand to 2010, 1993
NASA Astrophysics Data System (ADS)
1993-01-01
The paper summarizes the 1993 edition of the Gas Research Institute (GRI) Baseline Projection of U.S. Energy Supply and Demand and presents the implications of the projections that are important for GRI research and development planning and the gas industry. The survey of supply and demand considerations is followed by a breakdown of energy demand by type of fuel, by consumption sector, and by service application. Gas supply and prices are analyzed in terms of two scenarios: a constrained energy demand scenario, and an optimistic scenario. Tables and charts accompany the summary.
Spanish version of Bus Drivers' Job Demands Scale (BDJD-24).
Boada-Grau, Joan; Prizmic-Kuzmica, Aldo-Javier; González-Fernández, Marcos-David; Vigil-Colet, Andreu
2013-01-01
Karasek and Theorell's Job Demands-Control Model argues that adverse health-related outcomes, both psychological and physiological, arise from a combination of high job demand and a low level of job control. The objective was to adapt Meijman and Kompier's Bus Drivers' Job Demands Scale (BDJD-24), which enables us to assess the job demands of bus drivers, to Spanish. The final version of the Spanish adaptation was applied to a sample made up of 287 bus drivers living in Spain (80.1% men and 19.9% women), whose average age was 40.44 (SD= 11.78). The results yielded a three-factor structure for the scale used: Time Pressure, Safety, and Passengers. These findings confirm that the Spanish version replicates the factor structure of the original English scale. The reliability of the three subscales was acceptable, ranging from .75 to .84. Furthermore, the subscales were also related to different external correlates and to other scales and showed good convergent and criterion validity. The present instrument can be used to evaluate job demands of bus drivers, as its psychometrics are substantially sound.
ERIC Educational Resources Information Center
Bohndick, Carla; Rosman, Tom; Kohlmeyer, Susanne; Buhl, Heike M.
2018-01-01
In this study, we draw on person-environment fit theory to analyze whether academic success is best explained by individual abilities subjectively "exceeding" situational demands or by abilities "matching" the demands. Moreover, we disentangled effects of perceived abilities and subjective person-environment (P-E) fit on…
Code of Federal Regulations, 2010 CFR
2010-04-01
... in determining whether the Department will comply with a demand or request. (a) In deciding whether... applicable rules of discovery or the rules of procedure governing the case or matter in which the demand... for the conduct of official business; (5) The need to avoid spending the time and money of the United...
Multiple-Use Site Demand Analysis: An Application to the Boundary Waters Canoe Area Wilderness.
ERIC Educational Resources Information Center
Peterson, George L.; And Others
1982-01-01
A single-site, multiple-use model for analyzing trip demand is derived from a multiple site regional model based on utility maximizing choice theory. The model is used to analyze and compare trips to the Boundary Waters Canoe Area Wilderness for several types of use. Travel cost elasticities of demand are compared and discussed. (Authors/JN)
ERIC Educational Resources Information Center
Corgiat, Mark D.; And Others
1989-01-01
Evaluated contributions of age, presentation modality, task demand, and content structure to prose recall variation among adults. Tested 60 young and 60 older adults for recall of ideas in 641-word prose passage. Found recall for total number of idea units was significantly lower for older participants and for auditory presentation across both age…
ERIC Educational Resources Information Center
Pavias, Marcella; van den Broek, Paul; Hickendorff, Marian; Beker, Katinka; Van Leijenhorst, Linda
2016-01-01
This study examined the contributions of developmental changes in social-cognitive ability throughout adolescence to the development of narrative comprehension. We measured the effects of sensitivity to the causal structure of narratives and of sensitivity to differences in social-cognitive processing demands on narrative recall by children (8-10…
NASA Astrophysics Data System (ADS)
Zheng, Xianwei; Xiong, Hanjiang; Gong, Jianya; Yue, Linwei
2017-07-01
Virtual globes play an important role in representing three-dimensional models of the Earth. To extend the functioning of a virtual globe beyond that of a "geobrowser", the accuracy of the geospatial data in the processing and representation should be of special concern for the scientific analysis and evaluation. In this study, we propose a method for the processing of large-scale terrain data for virtual globe visualization and analysis. The proposed method aims to construct a morphologically preserved multi-resolution triangulated irregular network (TIN) pyramid for virtual globes to accurately represent the landscape surface and simultaneously satisfy the demands of applications at different scales. By introducing cartographic principles, the TIN model in each layer is controlled with a data quality standard to formulize its level of detail generation. A point-additive algorithm is used to iteratively construct the multi-resolution TIN pyramid. The extracted landscape features are also incorporated to constrain the TIN structure, thus preserving the basic morphological shapes of the terrain surface at different levels. During the iterative construction process, the TIN in each layer is seamlessly partitioned based on a virtual node structure, and tiled with a global quadtree structure. Finally, an adaptive tessellation approach is adopted to eliminate terrain cracks in the real-time out-of-core spherical terrain rendering. The experiments undertaken in this study confirmed that the proposed method performs well in multi-resolution terrain representation, and produces high-quality underlying data that satisfy the demands of scientific analysis and evaluation.
NASA Technical Reports Server (NTRS)
Bassler, Julie A.; Bodiford, Melanie P.; Fiske, Michael R.; Strong, Janet D.
2005-01-01
NASA's human exploration initiative poses great opportunity and great risk for manned missions to the Moon and Mars. Engineers and Scientists at the Marshall Space Flight Center are evaluating current technologies for in situ exploration habitat and fabrication and repair applications. Several technologies to be addressed in this paper have technology readiness levels (TRLs) that are currently mature enough to pursue for exploration purposes. However, many technologies offer promising applications but these must be pulled along by the demands and applications of this great initiative. The In Situ Fabrication and Repair (ISFR) program will supply and push state of the art technologies for applications such as habitat structure development, in situ resource utilization for tool and part fabrication, and repair and replacement of common life support elements. This paper will look at the current and future habitat technology applications such as the implementation of in situ environmental elements such as caves, rilles and lavatubes, the development of lunar regolith concrete and structure design and development, thin film and inflatable technologies. We will address current rapid prototyping technologies, their ISFR applications and near term advancements. We will discuss the anticipated need to utilize in situ resources to produce replacement parts and fabricate repairs to vehicles, habitats, life support and quality of life elements. All ISFR technology developments will incorporate automated deployment and robotic construction and fabrication techniques. The current state of the art for these applications is fascinating, but the future is out of this world.
Review of Large Spacecraft Deployable Membrane Antenna Structures
NASA Astrophysics Data System (ADS)
Liu, Zhi-Quan; Qiu, Hui; Li, Xiao; Yang, Shu-Li
2017-11-01
The demand for large antennas in future space missions has increasingly stimulated the development of deployable membrane antenna structures owing to their light weight and small stowage volume. However, there is little literature providing a comprehensive review and comparison of different membrane antenna structures. Space-borne membrane antenna structures are mainly classified as either parabolic or planar membrane antenna structures. For parabolic membrane antenna structures, there are five deploying and forming methods, including inflation, inflation-rigidization, elastic ribs driven, Shape Memory Polymer (SMP)-inflation, and electrostatic forming. The development and detailed comparison of these five methods are presented. Then, properties of membrane materials (including polyester film and polyimide film) for parabolic membrane antennas are compared. Additionally, for planar membrane antenna structures, frame shapes have changed from circular to rectangular, and different tensioning systems have emerged successively, including single Miura-Natori, double, and multi-layer tensioning systems. Recent advances in structural configurations, tensioning system design, and dynamic analysis for planar membrane antenna structures are investigated. Finally, future trends for large space membrane antenna structures are pointed out and technical problems are proposed, including design and analysis of membrane structures, materials and processes, membrane packing, surface accuracy stability, and test and verification technology. Through a review of large deployable membrane antenna structures, guidance for space membrane-antenna research and applications is provided.
Vimal, Archana; Kumar, Awanish
2017-03-01
l-asparaginase is an enzyme of medical prominence and reputable as a chemotherapeutic agent. It also has immense potential to cure autoimmune and infectious diseases. The vast application of this enzyme in healthcare sector increases its market demand. However, presently the huge market demand is not achieved completely. This serves the basis to explore better producer microbial strains to bridge the gap between huge demand and supply of this therapeutic enzyme. The present study deals with the successful screening of potent microorganisms producing l-asparaginase. 47 microorganisms were screened including bacteria, fungi, and yeasts. Among all, Penicillium lilacinum showed the highest enzyme activity i.e., 39.67 IU/ml. Shigella flexneri has 23.21 IU/ml of enzyme activity (highest among all the bacterial strain tested). Further, the 3-D structure of l-asparaginase from higher producer strains was developed and validated in silico for its activity. l-asparagine (substrate for l-asparaginase) was docked inside the binding pocket of P. lilacinum and S. flexneri. Docking score for the most common substrate l-asparagine is -6.188 (P. lilacinum), -5.576 (S. flexneri) which is quite good. Moreover, the chemical property of the binding pocket revealed that amino acid residues Phe 243, Gln 260, Gly 365, Asp 386 in P. lilacinum and residues Asp 181, Thr 318, Asn 320 in S. flexneri have an important role in H-bonding. The in silico results supports and strengthen the wet lab results. The outcome obtained motivates to take the present study result from lab to industry for the economic/massive production of this enzyme for the diverse therapeutic application. Copyright © 2016 Elsevier Inc. All rights reserved.
Recognition of functional sites in protein structures.
Shulman-Peleg, Alexandra; Nussinov, Ruth; Wolfson, Haim J
2004-06-04
Recognition of regions on the surface of one protein, that are similar to a binding site of another is crucial for the prediction of molecular interactions and for functional classifications. We first describe a novel method, SiteEngine, that assumes no sequence or fold similarities and is able to recognize proteins that have similar binding sites and may perform similar functions. We achieve high efficiency and speed by introducing a low-resolution surface representation via chemically important surface points, by hashing triangles of physico-chemical properties and by application of hierarchical scoring schemes for a thorough exploration of global and local similarities. We proceed to rigorously apply this method to functional site recognition in three possible ways: first, we search a given functional site on a large set of complete protein structures. Second, a potential functional site on a protein of interest is compared with known binding sites, to recognize similar features. Third, a complete protein structure is searched for the presence of an a priori unknown functional site, similar to known sites. Our method is robust and efficient enough to allow computationally demanding applications such as the first and the third. From the biological standpoint, the first application may identify secondary binding sites of drugs that may lead to side-effects. The third application finds new potential sites on the protein that may provide targets for drug design. Each of the three applications may aid in assigning a function and in classification of binding patterns. We highlight the advantages and disadvantages of each type of search, provide examples of large-scale searches of the entire Protein Data Base and make functional predictions.
Deployable antenna kinematics using tensegrity structure design
NASA Astrophysics Data System (ADS)
Knight, Byron Franklin
With vast changes in spacecraft development over the last decade, a new, cheaper approach was needed for deployable kinematic systems such as parabolic antenna reflectors. Historically, these mesh-surface reflectors have resembled folded umbrellas, with incremental redesigns utilized to save packaging size. These systems are typically over-constrained designs, the assumption being that high reliability necessary for space operations requires this level of conservatism. But with the rapid commercialization of space, smaller launch platforms and satellite buses have demanded much higher efficiency from all space equipment than can be achieved through this incremental approach. This work applies an approach called tensegrity to deployable antenna development. Kenneth Snelson, a student of R. Buckminster Fuller, invented Tensegrity structures in 1948. Such structures use a minimum number of compression members (struts); stability is maintain using tension members (ties). The novelty introduced in this work is that the ties are elastic, allowing the struts to extend or contract, and in this way changing the surface of the antenna. Previously, the University of Florida developed an approach to quantify the stability and motion of parallel manipulators. This approach was applied to deployable, tensegrity, antenna structures. Based on the kinematic analyses for the 3-3 (octahedron) and 4-4 (square anti-prism) structures, the 6-6 (hexagonal anti-prism) analysis was completed which establishes usable structural parameters. The primary objective for this work was to prove the stability of this class of deployable structures, and their potential application to space structures. The secondary objective is to define special motions for tensegrity antennas, to meet the subsystem design requirements, such as addressing multiple antenna-feed locations. This work combines the historical experiences of the artist (Snelson), the mathematician (Ball), and the space systems engineer (Wertz) to develop a new, practical design approach. This kinematic analysis of tensegrity structures blends these differences to provide the design community with a new approach to lightweight, robust, adaptive structures with the high reliability that space demands. Additionally, by applying Screw Theory, a tensegrity structure antenna can be commanded to move along a screw axis, and therefore meeting the requirement to address multiple feed locations.
Different types of employee well-being across time and their relationships with job crafting.
Hakanen, Jari J; Peeters, Maria C W; Schaufeli, Wilmar B
2018-04-01
We used and integrated the circumplex model of affect (Russell, 1980) and the conservation of resources theory (Hobfoll, 1998) to hypothesize how various types of employee well-being, which can be differentiated on theoretical grounds (i.e., work engagement, job satisfaction, burnout, and workaholism), may differently predict various job crafting behaviors (i.e., increasing structural and social resources and challenging demands, and decreasing hindering demands) and each other over time. At Time 1, we measured employee well-being, and 4 years later at Time 2, job crafting and well-being, using a large sample of Finnish dentists (N = 1,877). The results of structural equation modeling showed that (a) work engagement positively predicted both types of increasing resources and challenging demands and negatively predicted decreasing hindering demands; (b) workaholism positively predicted increasing structural resources and challenging demands; (c) burnout positively predicted decreasing hindering demands and negatively predicted increasing structural resources, whereas (d) job satisfaction did not relate to job crafting over time; and (e) work engagement positively influenced job satisfaction and negatively influenced burnout, whereas (f) workaholism predicted burnout after controlling for baseline levels. Thus, work engagement was a stronger predictor of future job crafting and other types of employee well-being than job satisfaction. Although workaholism was positively associated with job crafting, it also predicted burnout. We conclude that the relationship between job crafting and employee well-being may be more complex than assumed, because the way in which employees will craft their jobs in the future seems to depend on how they currently feel. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Multifunctional 3D printing of heterogeneous hydrogel structures
NASA Astrophysics Data System (ADS)
Nadernezhad, Ali; Khani, Navid; Skvortsov, Gözde Akdeniz; Toprakhisar, Burak; Bakirci, Ezgi; Menceloglu, Yusuf; Unal, Serkan; Koc, Bahattin
2016-09-01
Multimaterial additive manufacturing or three-dimensional (3D) printing of hydrogel structures provides the opportunity to engineer geometrically dependent functionalities. However, current fabrication methods are mostly limited to one type of material or only provide one type of functionality. In this paper, we report a novel method of multimaterial deposition of hydrogel structures based on an aspiration-on-demand protocol, in which the constitutive multimaterial segments of extruded filaments were first assembled in liquid state by sequential aspiration of inks into a glass capillary, followed by in situ gel formation. We printed different patterned objects with varying chemical, electrical, mechanical, and biological properties by tuning process and material related parameters, to demonstrate the abilities of this method in producing heterogeneous and multi-functional hydrogel structures. Our results show the potential of proposed method in producing heterogeneous objects with spatially controlled functionalities while preserving structural integrity at the switching interface between different segments. We anticipate that this method would introduce new opportunities in multimaterial additive manufacturing of hydrogels for diverse applications such as biosensors, flexible electronics, tissue engineering and organ printing.
Databases, Repositories, and Other Data Resources in Structural Biology.
Zheng, Heping; Porebski, Przemyslaw J; Grabowski, Marek; Cooper, David R; Minor, Wladek
2017-01-01
Structural biology, like many other areas of modern science, produces an enormous amount of primary, derived, and "meta" data with a high demand on data storage and manipulations. Primary data come from various steps of sample preparation, diffraction experiments, and functional studies. These data are not only used to obtain tangible results, like macromolecular structural models, but also to enrich and guide our analysis and interpretation of various biomedical problems. Herein we define several categories of data resources, (a) Archives, (b) Repositories, (c) Databases, and (d) Advanced Information Systems, that can accommodate primary, derived, or reference data. Data resources may be used either as web portals or internally by structural biology software. To be useful, each resource must be maintained, curated, as well as integrated with other resources. Ideally, the system of interconnected resources should evolve toward comprehensive "hubs", or Advanced Information Systems. Such systems, encompassing the PDB and UniProt, are indispensable not only for structural biology, but for many related fields of science. The categories of data resources described herein are applicable well beyond our usual scientific endeavors.
Databases, Repositories and Other Data Resources in Structural Biology
Zheng, Heping; Porebski, Przemyslaw J.; Grabowski, Marek; Cooper, David R.; Minor, Wladek
2017-01-01
Structural biology, like many other areas of modern science, produces an enormous amount of primary, derived, and “meta” data with a high demand on data storage and manipulations. Primary data comes from various steps of sample preparation, diffraction experiments, and functional studies. These data are not only used to obtain tangible results, like macromolecular structural models, but also to enrich and guide our analysis and interpretation of existing biomedical studies. Herein we define several categories of data resources, (a) Archives, (b) Repositories, (c) “Databases” and (d) Advanced Information Systems, that can accommodate primary, derived, or reference data. Data resources may be used either as web portals or internally by structural biology software. To be useful, each resource must be maintained, curated, and be integrated with other resources. Ideally, the system of interconnected resources should evolve toward comprehensive “hubs” or Advanced Information Systems. Such systems, encompassing the PDB and UniProt, are indispensable not only for structural biology, but for many related fields of science. The categories of data resources described herein are applicable well beyond our usual scientific endeavors. PMID:28573593
Multifunctional 3D printing of heterogeneous hydrogel structures
Nadernezhad, Ali; Khani, Navid; Skvortsov, Gözde Akdeniz; Toprakhisar, Burak; Bakirci, Ezgi; Menceloglu, Yusuf; Unal, Serkan; Koc, Bahattin
2016-01-01
Multimaterial additive manufacturing or three-dimensional (3D) printing of hydrogel structures provides the opportunity to engineer geometrically dependent functionalities. However, current fabrication methods are mostly limited to one type of material or only provide one type of functionality. In this paper, we report a novel method of multimaterial deposition of hydrogel structures based on an aspiration-on-demand protocol, in which the constitutive multimaterial segments of extruded filaments were first assembled in liquid state by sequential aspiration of inks into a glass capillary, followed by in situ gel formation. We printed different patterned objects with varying chemical, electrical, mechanical, and biological properties by tuning process and material related parameters, to demonstrate the abilities of this method in producing heterogeneous and multi-functional hydrogel structures. Our results show the potential of proposed method in producing heterogeneous objects with spatially controlled functionalities while preserving structural integrity at the switching interface between different segments. We anticipate that this method would introduce new opportunities in multimaterial additive manufacturing of hydrogels for diverse applications such as biosensors, flexible electronics, tissue engineering and organ printing. PMID:27630079
NASA Astrophysics Data System (ADS)
Cattaneo, Alessandro; Park, Gyuhae; Farrar, Charles; Mascareñas, David
2012-04-01
The acoustic emission (AE) phenomena generated by a rapid release in the internal stress of a material represent a promising technique for structural health monitoring (SHM) applications. AE events typically result in a discrete number of short-time, transient signals. The challenge associated with capturing these events using classical techniques is that very high sampling rates must be used over extended periods of time. The result is that a very large amount of data is collected to capture a phenomenon that rarely occurs. Furthermore, the high energy consumption associated with the required high sampling rates makes the implementation of high-endurance, low-power, embedded AE sensor nodes difficult to achieve. The relatively rare occurrence of AE events over long time scales implies that these measurements are inherently sparse in the spike domain. The sparse nature of AE measurements makes them an attractive candidate for the application of compressed sampling techniques. Collecting compressed measurements of sparse AE signals will relax the requirements on the sampling rate and memory demands. The focus of this work is to investigate the suitability of compressed sensing techniques for AE-based SHM. The work explores estimating AE signal statistics in the compressed domain for low-power classification applications. In the event compressed classification finds an event of interest, ι1 norm minimization will be used to reconstruct the measurement for further analysis. The impact of structured noise on compressive measurements is specifically addressed. The suitability of a particular algorithm, called Justice Pursuit, to increase robustness to a small amount of arbitrary measurement corruption is investigated.
Spatial and temporal control of microwave triggered chemiluminescence: a protein detection platform.
Previte, Michael J R; Aslan, Kadir; Geddes, Chris D
2007-09-15
We have combined the principles of microwave circuitry and antenna design and our recent work in microwave-triggered metal-enhanced chemiluminescence to now "trigger" chemically and enzyme-catalyzed chemiluminescent reactions with spatial and temporal control. With this technology platform, we achieve spatial and temporal control of enzyme and chemically catalyzed chemiluminescence reactions to achieve more than 500-fold increases in "on-demand" photon flux from chemically catalyzed chemiluminescent reactions. We also report a 6-fold increase in photon flux from HRP-catalyzed assays on disposable coverslips functionalized with HRP and placed proximal to the substrates modified with thin-film aluminum triangle disjointed "bow-tie" structures. In addition, we demonstrate the applicability of this technology to develop multiplexed or high-throughput chemiluminescent assays. We also demonstrate the clinical and biological relevance of this technology platform by affixing aluminum structures in proximity to HRP protein immobilized on nitrocellulose to improve the sensitivity for this model Western blot scheme by 50-fold. We believe analytical applications that rely on enzyme-catalyzed chemiluminescence, such as immunoassays, may greatly benefit from this new platform technology.
Perspective: Machine learning potentials for atomistic simulations
NASA Astrophysics Data System (ADS)
Behler, Jörg
2016-11-01
Nowadays, computer simulations have become a standard tool in essentially all fields of chemistry, condensed matter physics, and materials science. In order to keep up with state-of-the-art experiments and the ever growing complexity of the investigated problems, there is a constantly increasing need for simulations of more realistic, i.e., larger, model systems with improved accuracy. In many cases, the availability of sufficiently efficient interatomic potentials providing reliable energies and forces has become a serious bottleneck for performing these simulations. To address this problem, currently a paradigm change is taking place in the development of interatomic potentials. Since the early days of computer simulations simplified potentials have been derived using physical approximations whenever the direct application of electronic structure methods has been too demanding. Recent advances in machine learning (ML) now offer an alternative approach for the representation of potential-energy surfaces by fitting large data sets from electronic structure calculations. In this perspective, the central ideas underlying these ML potentials, solved problems and remaining challenges are reviewed along with a discussion of their current applicability and limitations.
Variation in the electrical properties of ion beam irradiated cadmium selenate nanowires
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chauhan, R. P., E-mail: chauhanrpc@gmail.com; Narula, Chetna; Panchal, Suresh
The key feature of nanowires consists in the pronounced change in properties induced by the low dimensionality and high surface to volume ratio. The study of electrical transport properties of nanowires is important for electronic device applications. Energetic ions create changes, which may be structural or chemical, in a material along their track and these changes might alter the material’s properties. The demand of the modern technology is to understand the effect of radiation on the different properties of the material for its further applications. The present study is on the high-energy Nickel ion beam (160 MeV Ni{sup +12}) induced modificationsmore » in the electrical and structural properties of the cadmium selenate nanowires. An enhancement in the electrical conductivity of irradiated wires was observed as the ion fluence was increased especially in the forward I–V characteristics. The creation of defects by ion irradiation and the synergy of the ions during their passage in the sample with the intrinsic charge carriers may be responsible for the variation in the transport properties of the irradiated nanowires.« less
Cholesteric liquid crystals doped with gold nanoparticles
NASA Astrophysics Data System (ADS)
Bitar, Rajaa; Agez, Gonzague; Mitov, Michel
2012-10-01
The reflection color of a cholesteric liquid crystal depends on material parameters such as the molecular chirality or the concentration of chiral dopant, the helical pitch of the twisted structure and the optical indices. We show that the color may be selected simply by varying the annealing time of an open cholesteric oligomer film with hybrid anchoring. The 3D representation of the structure is provided by combining complementary imaging techniques. The color selectivity is due to controlled changes of the orientation of the helix axis with respect to the air-material interface. Potential applications are chiral microreflectors and microlenses. Then, we demonstrate the symbiotic association of gold nanoparticles within such cholesteric textures and their long-range self-organized arrangements. We show that the nanoparticles can be patterned on demand only by playing with the film thickness and the interfacial properties of the CLC film. We investigate how the selective reflection is affected by the in situ organization of gold nanoparticles and what is the plasmon response of nanoparticle chains. Potential applications are envisioned in the field of soft nanotechnology and optical materials.
Jia, Yuechen; Cheng, Chen; Vázquez de Aldana, Javier R.; Castillo, Gabriel R.; Rabes, Blanca del Rosal; Tan, Yang; Jaque, Daniel; Chen, Feng
2014-01-01
Miniature laser sources with on-demand beam features are desirable devices for a broad range of photonic applications. Lasing based on direct-pump of miniaturized waveguiding active structures offers a low-cost but intriguing solution for compact light-emitting devices. In this work, we demonstrate a novel family of three dimensional (3D) photonic microstructures monolithically integrated in a Nd:YAG laser crystal wafer. They are produced by the femtosecond laser writing, capable of simultaneous light waveguiding and beam manipulation. In these guiding systems, tailoring of laser modes by both passive/active beam splitting and ring-shaped transformation are achieved by an appropriate design of refractive index patterns. Integration of graphene thin-layer as saturable absorber in the 3D laser structures allows for efficient passive Q-switching of tailored laser radiations which may enable miniature waveguiding lasers for broader applications. Our results pave a way to construct complex integrated passive and active laser circuits in dielectric crystals by using femtosecond laser written monolithic photonic chips. PMID:25100561
Studies on Tribological Behavior of Aluminum Nitride-Coated Steel
NASA Astrophysics Data System (ADS)
Ionescu, G. C.; Nae, I.; Ripeanu, R. G.; Dinita, A.; Stan, G.
2017-02-01
The new opportunities introduced by the large development of the IoT (internet of things) are increasing the demand for sensors to be located as close as possible to the supervised process. The Aluminum Nitride (AIN) is one of the most promising materials for sensors due to its piezoelectric, excellent mechanical properties, chemical inertness and high melting point. Due to these material properties, the AlN sensors are suitable to operate in high temperature and harsh environment conditions and therefore are very promising to be employed in industrial applications. In this article are presented the studies conducted on several Aluminum Nitride-Coated Steel structures with the goal of producing sensors embedded in the ball bearings, bearings and other mobile parts of machine tools. The experiments were conducted on simple coatings structures without lubricating materials and the obtained results are promising, demonstrating that, with some limitations the AIN could be used in such applications. This paper was accepted for publication in Proceedings after double peer reviewing process but was not presented at the Conference ROTRIB’16
NASA Astrophysics Data System (ADS)
Kouziokas, Georgios N.
2016-01-01
The adoption of Information and Communication Technologies (ICT) in environmental management has become a significant demand nowadays with the rapid growth of environmental information. This paper presents a prototype Environmental Management Information System (EMIS) that was developed to provide a systematic way of managing environmental data and human resources of an environmental organization. The system was designed using programming languages, a Database Management System (DBMS) and other technologies and programming tools and combines information from the relational database in order to achieve the principal goals of the environmental organization. The developed application can be used to store and elaborate information regarding: human resources data, environmental projects, observations, reports, data about the protected species, environmental measurements of pollutant factors or other kinds of analytical measurements and also the financial data of the organization. Furthermore, the system supports the visualization of spatial data structures by using geographic information systems (GIS) and web mapping technologies. This paper describes this prototype software application, its structure, its functions and how this system can be utilized to facilitate technology-based environmental management and decision-making process.
Highly Flexible Dye-sensitized Solar Cells Produced by Sewing Textile Electrodes on Cloth
Yun, Min Ju; Cha, Seung I.; Seo, Seon Hee; Lee, Dong Y.
2014-01-01
Textile forms of solar cells possess special advantages over other types of solar cells, including their light weight, high flexibility, and mechanical robustness. Recent demand for wearable devices has promoted interest in the development of high-efficiency textile-based solar cells for energy suppliers. However, the weaving process occurs under high-friction, high-tension conditions that are not conducive to coated solar-cell active layers or electrodes deposited on the wire or strings. Therefore, a new approach is needed for the development of textile-based solar cells suitable for woven fabrics for wide-range application. In this report, we present a highly flexible, efficient DSSC, fabricated by sewing textile-structured electrodes onto casual fabrics such as cotton, silk, and felt, or paper, thereby forming core integrated DSSC structures with high energy-conversion efficiency (~5.8%). The fabricated textile-based DSSC devices showed high flexibility and high performance under 4-mm radius of curvature over thousands of deformation cycles. Considering the vast number of textile types, our textile-based DSSC devices offer a huge range of applications, including transparent, stretchable, wearable devices. PMID:24957920
Highly flexible dye-sensitized solar cells produced by sewing textile electrodes on cloth.
Yun, Min Ju; Cha, Seung I; Seo, Seon Hee; Lee, Dong Y
2014-06-24
Textile forms of solar cells possess special advantages over other types of solar cells, including their light weight, high flexibility, and mechanical robustness. Recent demand for wearable devices has promoted interest in the development of high-efficiency textile-based solar cells for energy suppliers. However, the weaving process occurs under high-friction, high-tension conditions that are not conducive to coated solar-cell active layers or electrodes deposited on the wire or strings. Therefore, a new approach is needed for the development of textile-based solar cells suitable for woven fabrics for wide-range application. In this report, we present a highly flexible, efficient DSSC, fabricated by sewing textile-structured electrodes onto casual fabrics such as cotton, silk, and felt, or paper, thereby forming core integrated DSSC structures with high energy-conversion efficiency (~5.8%). The fabricated textile-based DSSC devices showed high flexibility and high performance under 4-mm radius of curvature over thousands of deformation cycles. Considering the vast number of textile types, our textile-based DSSC devices offer a huge range of applications, including transparent, stretchable, wearable devices.
Huang, Chun; Zhang, Jin; Young, Neil P; Snaith, Henry J; Grant, Patrick S
2016-05-10
Supercapacitors are in demand for short-term electrical charge and discharge applications. Unlike conventional supercapacitors, solid-state versions have no liquid electrolyte and do not require robust, rigid packaging for containment. Consequently they can be thinner, lighter and more flexible. However, solid-state supercapacitors suffer from lower power density and where new materials have been developed to improve performance, there remains a gap between promising laboratory results that usually require nano-structured materials and fine-scale processing approaches, and current manufacturing technology that operates at large scale. We demonstrate a new, scalable capability to produce discrete, multi-layered electrodes with a different material and/or morphology in each layer, and where each layer plays a different, critical role in enhancing the dynamics of charge/discharge. This layered structure allows efficient utilisation of each material and enables conservative use of hard-to-obtain materials. The layered electrode shows amongst the highest combinations of energy and power densities for solid-state supercapacitors. Our functional design and spray manufacturing approach to heterogeneous electrodes provide a new way forward for improved energy storage devices.
Hydrogen adsorption in metal-decorated silicon carbide nanotubes
NASA Astrophysics Data System (ADS)
Singh, Ram Sevak; Solanki, Ankit
2016-09-01
Hydrogen storage for fuel cell is an active area of research and appropriate materials with excellent hydrogen adsorption properties are highly demanded. Nanotubes, having high surface to volume ratio, are promising storage materials for hydrogen. Recently, silicon carbide nanotubes have been predicted as potential materials for future hydrogen storage application, and studies in this area are ongoing. Here, we report a systematic study on hydrogen adsorption properties in metal (Pt, Ni and Al) decorated silicon carbide nanotubes (SiCNTs) using first principles calculations based on density functional theory. The hydrogen adsorption properties are investigated by calculations of adsorption energy, electronic band structure, density of states (DOS) and Mulliken charge population analysis. Our findings show that hydrogen adsorptions on Pt, Ni and Al-decorated SiCNTs undergo spontaneous exothermic reactions with significant modulation of electronic structure of SiCNTs in all cases. Importantly, according to the Mulliken charge population analysis, dipole-dipole interaction causes chemisorptions of hydrogen in Pt, Ni and Al decorated SiCNTs with formation of chemical bonds. The study is a platform for the development of metal decorated SiCNTs for hydrogen adsorption or hydrogen storage application.
Seismic Response Control Of Structures Using Semi-Active and Passive Variable Stiffness Devices
NASA Astrophysics Data System (ADS)
Salem, Mohamed M. A.
Controllable devices such as Magneto-Rheological Fluid Dampers, Electro-Rheological Dampers, and controllable friction devices have been studied extensively with limited implementation in real structures. Such devices have shown great potential in reducing seismic demands, either as smart base isolation systems, or as smart devices for multistory structures. Although variable stiffness devices can be used for seismic control of structures, the vast majority of research effort has been given to the control of damping. The primary focus of this dissertation is to evaluate the seismic control of structures using semi-active and passive variable stiffness characteristics. Smart base isolation systems employing variable stiffness devices have been studied, and two semi-active control strategies are proposed. The control algorithms were designed to reduce the superstructure and base accelerations of seismically isolated structures subject to near-fault and far-field ground motions. Computational simulations of the proposed control algorithms on the benchmark structure have shown that excessive base displacements associated with the near-fault ground motions may be better mitigated with the use of variable stiffness devices. However, the device properties must be controllable to produce a wide range of stiffness changes for an effective control of the base displacements. The potential of controllable stiffness devices in limiting the base displacement due to near-fault excitation without compromising the performance of conventionally isolated structures, is illustrated. The application of passive variable stiffness devices for seismic response mitigation of multistory structures is also investigated. A stiffening bracing system (SBS) is proposed to replace the conventional bracing systems of braced frames. An optimization process for the SBS parameters has been developed. The main objective of the design process is to maintain a uniform inter-story drift angle over the building's height, which in turn would evenly distribute the seismic demand over the building. This behavior is particularly essential so that any possible damage is not concentrated in a single story. Furthermore, the proposed design ensures that additional damping devices distributed over the building's height work efficiently with their maximum design capacity, leading to a cost efficient design. An integrated and comprehensive design procedure that can be readily adopted by the current seismic design codes is proposed. An equivalent lateral force distribution is developed that shows a good agreement with the response history analyses in terms of seismic performance and demand prediction. This lateral force pattern explicitly accounts for the higher mode effect, the dynamic characteristics of the structure, the supplemental damping, and the site specific seismic hazard. Therefore, the proposed design procedure is considered as a standalone method for the design of SBS equipped buildings.
Crawford, Eean R; Lepine, Jeffery A; Rich, Bruce Louis
2010-09-01
We refine and extend the job demands-resources model with theory regarding appraisal of stressors to account for inconsistencies in relationships between demands and engagement, and we test the revised theory using meta-analytic structural modeling. Results indicate support for the refined and updated theory. First, demands and burnout were positively associated, whereas resources and burnout were negatively associated. Second, whereas relationships among resources and engagement were consistently positive, relationships among demands and engagement were highly dependent on the nature of the demand. Demands that employees tend to appraise as hindrances were negatively associated with engagement, and demands that employees tend to appraise as challenges were positively associated with engagement. Implications for future research are discussed. Copyright 2010 APA, all rights reserved
Bagheri Hosseinabadi, Majid; Etemadinezhad, Siavash; Khanjani, Narges; Ahmadi, Omran; Gholinia, Hemat; Galeshi, Mina; Samaei, Seyed Ehsan
2018-01-01
Background: This study was designed to investigate job satisfaction and its relation to perceived job stress among hospital nurses in Babol County, Iran. Methods: This cross-sectional study was conducted on 406 female nurses in 6 Babol hospitals. Respondents completed the Minnesota Satisfaction Questionnaire (MSQ), the health and safety executive (HSE) indicator tool and a demographic questionnaire. Descriptive, analytical and structural equation modeling (SEM) analyses were carried out applying SPSS v. 22 and AMOS v. 22. Results: The Normed Fit Index (NFI), Non-normed Fit Index (NNFI), Incremental Fit Index (IFI)and Comparative Fit Index (CFI) were greater than 0.9. Also, goodness of fit index (GFI=0.99)and adjusted goodness of fit index (AGFI) were greater than 0.8, and root mean square error of approximation (RMSEA) were 0.04, The model was found to be with an appropriate fit. The R-squared was 0.42 for job satisfaction, and all its dimensions were related to job stress. The dimensions of job stress explained 42% of changes in the variance of job satisfaction. There was a significant relationship between the dimensions of job stress such as demand (β =0.173,CI =0.095 - 0.365, P≤0.001), control (β =0.135, CI =0.062 - 0.404, P =0.008), relationships(β =-0.208, CI =-0.637- -0.209; P≤0.001) and changes (β =0.247, CI =0.360 - 1.026, P≤0.001)with job satisfaction. Conclusion: One of the important interventions to increase job satisfaction among nurses maybe improvement in the workplace. Reducing the level of workload in order to improve job demand and minimizing role conflict through reducing conflicting demands are recommended.
Bagheri Hosseinabadi, Majid; Etemadinezhad, Siavash; khanjani, Narges; Ahmadi, Omran; Gholinia, Hemat; Galeshi, Mina; Samaei, Seyed Ehsan
2018-01-01
Background: This study was designed to investigate job satisfaction and its relation to perceived job stress among hospital nurses in Babol County, Iran. Methods: This cross-sectional study was conducted on 406 female nurses in 6 Babol hospitals. Respondents completed the Minnesota Satisfaction Questionnaire (MSQ), the health and safety executive (HSE) indicator tool and a demographic questionnaire. Descriptive, analytical and structural equation modeling (SEM) analyses were carried out applying SPSS v. 22 and AMOS v. 22. Results: The Normed Fit Index (NFI), Non-normed Fit Index (NNFI), Incremental Fit Index (IFI)and Comparative Fit Index (CFI) were greater than 0.9. Also, goodness of fit index (GFI=0.99)and adjusted goodness of fit index (AGFI) were greater than 0.8, and root mean square error of approximation (RMSEA) were 0.04, The model was found to be with an appropriate fit. The R-squared was 0.42 for job satisfaction, and all its dimensions were related to job stress. The dimensions of job stress explained 42% of changes in the variance of job satisfaction. There was a significant relationship between the dimensions of job stress such as demand (β =0.173,CI =0.095 - 0.365, P≤0.001), control (β =0.135, CI =0.062 - 0.404, P =0.008), relationships(β =-0.208, CI =-0.637– -0.209; P≤0.001) and changes (β =0.247, CI =0.360 - 1.026, P≤0.001)with job satisfaction. Conclusion: One of the important interventions to increase job satisfaction among nurses maybe improvement in the workplace. Reducing the level of workload in order to improve job demand and minimizing role conflict through reducing conflicting demands are recommended. PMID:29744305
Adaptations in Electronic Structure Calculations in Heterogeneous Environments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Talamudupula, Sai
Modern quantum chemistry deals with electronic structure calculations of unprecedented complexity and accuracy. They demand full power of high-performance computing and must be in tune with the given architecture for superior e ciency. To make such applications resourceaware, it is desirable to enable their static and dynamic adaptations using some external software (middleware), which may monitor both system availability and application needs, rather than mix science with system-related calls inside the application. The present work investigates scienti c application interlinking with middleware based on the example of the computational chemistry package GAMESS and middleware NICAN. The existing synchronous model ismore » limited by the possible delays due to the middleware processing time under the sustainable runtime system conditions. Proposed asynchronous and hybrid models aim at overcoming this limitation. When linked with NICAN, the fragment molecular orbital (FMO) method is capable of adapting statically and dynamically its fragment scheduling policy based on the computing platform conditions. Signi cant execution time and throughput gains have been obtained due to such static adaptations when the compute nodes have very di erent core counts. Dynamic adaptations are based on the main memory availability at run time. NICAN prompts FMO to postpone scheduling certain fragments, if there is not enough memory for their immediate execution. Hence, FMO may be able to complete the calculations whereas without such adaptations it aborts.« less
NASA Astrophysics Data System (ADS)
Bhave, Ajay; Dessai, Suraje; Conway, Declan; Stainforth, David
2016-04-01
Deep uncertainty in future climate change and socio-economic conditions necessitates the use of assess-risk-of-policy approaches over predict-then-act approaches for adaptation decision making. Robust Decision Making (RDM) approaches embody this principle and help evaluate the ability of adaptation options to satisfy stakeholder preferences under wide-ranging future conditions. This study involves the simultaneous application of two RDM approaches; qualitative and quantitative, in the Cauvery River Basin in Karnataka (population ~23 million), India. The study aims to (a) determine robust water resources adaptation options for the 2030s and 2050s and (b) compare the usefulness of a qualitative stakeholder-driven approach with a quantitative modelling approach. For developing a large set of future scenarios a combination of climate narratives and socio-economic narratives was used. Using structured expert elicitation with a group of climate experts in the Indian Summer Monsoon, climatic narratives were developed. Socio-economic narratives were developed to reflect potential future urban and agricultural water demand. In the qualitative RDM approach, a stakeholder workshop helped elicit key vulnerabilities, water resources adaptation options and performance criteria for evaluating options. During a second workshop, stakeholders discussed and evaluated adaptation options against the performance criteria for a large number of scenarios of climatic and socio-economic change in the basin. In the quantitative RDM approach, a Water Evaluation And Planning (WEAP) model was forced by precipitation and evapotranspiration data, coherent with the climatic narratives, together with water demand data based on socio-economic narratives. We find that compared to business-as-usual conditions options addressing urban water demand satisfy performance criteria across scenarios and provide co-benefits like energy savings and reduction in groundwater depletion, while options reducing agricultural water demand significantly affect downstream water availability. Water demand options demonstrate potential to improve environmental flow conditions and satisfy legal water supply requirements for downstream riparian states. On the other hand, currently planned large scale infrastructural projects demonstrate reduced value in certain scenarios, illustrating the impacts of lock-in effects of large scale infrastructure. From a methodological perspective, we find that while the stakeholder-driven approach revealed robust options in a resource-light manner and helped initiate much needed interaction amongst stakeholders, the modelling approach provides complementary quantitative information. The study reveals robust adaptation options for this important basin and provides a strong methodological basis for carrying out future studies that support adaptation decision making.
Perspective on the span-distributed-load concept for application to large cargo aircraft design
NASA Technical Reports Server (NTRS)
Whitehead, A. H., Jr.
1975-01-01
Results of a simplified analysis of the span-distributed-load concept (in which payload is placed within the wing structure) are presented. It is shown that a design based on these principles has a high potential for application to future large air cargo transport. Significant improvements are foreseen in increased payload fraction and productivity and in reduced fuel consumption and operating costs. A review of the efforts in the 1940's to develop all-wing aircraft shows the potential of transferring those early technological developments to current design of distributed-load aircraft. Current market analyses are projected to 1990 to show the future commercial demand for large capacity freighters. Several configuration designs which would serve different market requirements for these large freighters are discussed as are some of the pacing-technology requirements.
NASA Astrophysics Data System (ADS)
Dahmen, Martin; Lindner, Stefan; Monfort, Damien; Petring, Dirk
The increasing demand for ultra-high strength steels in vehicle manufacturing leads to the application of new alloys. This poses a challenge on joining especially by fusion welding. A stainless high manganese steel sheet with excellent strength and deformation properties stands in the centre of the development. Similar and dissimilar welds with a metastable austenitic steel and a hot formed martensitic stainless steel were performed. An investigation of the mixing effects on the local microstructure and the hardness delivers the metallurgical features of the welds. Despite of carbon contents above 0.4 wt.% none of the welds have shown cracks. Mechanical properties drawn from tensile tests deliver high breaking forces enabling a high stiffness of the joints. The results show the potential for the application of laser beam welding for joining in assembly of structural parts.
Applications of CPL mask technology for sub-65nm gate imaging
NASA Astrophysics Data System (ADS)
Litt, Lloyd C.; Conley, Will; Wu, Wei; Peters, Richie; Parker, Colita; Cobb, Jonathan; Kasprowicz, Bryan S.; van den Broeke, Doug; Park, J. C.; Karur-Shanmugam, Ramkumar
2005-05-01
The requirements for critical dimension control on gate layer for high performance products are increasingly demanding. Phase shift techniques provide aerial image enhancement, which can translate into improved process window performance and greater critical dimension (CD) control if properly applied. Unfortunately, the application of hard shifter technology to production requires significant effort in layout and optical proximity correction (OPC) application. Chromeless Phase Lithography (CPL) has several advantages over complementary phase mask (c:PSM) such as use of a single mask, and lack of phase placement 'coloring' conflicts and phase imbalance issues. CPL does have implementation issues that must be resolved before it can be used in full-scale production. CPL mask designs can be approached by separating features into three zones based on several parameters, including size relative to the lithographic resolution of the stepper lens, wavelength, and illumination conditions defined. Features are placed into buckets for different treatment zones. Zone 1 features are constructed with 100% transmission phase shifted structures and Zone 3 features are chrome (binary) structures. Features that fall into Zone 2, which are too wide to be defined using the 100% transmission of pure CPL (i.e. have negative mask error factor, MEEF) are the most troublesome and can be approached in several ways. The authors have investigated the application of zebra structures of various sizes to product type layouts. Previous work to investigate CPL using test structures set the groundwork for the more difficult task of applying CPL rules to actual random logic design layouts, which include many zone transitions. Mask making limitations have been identified that play a role in the zebra sizing that can be applied to Zone 2 features. The elimination of Zone 2 regions was also investigated in an effort to simplify the application of CPL and improve manufacturability of reticle through data enhancements.
A Cost-Benefit Study of Doing Astrophysics On The Cloud: Production of Image Mosaics
NASA Astrophysics Data System (ADS)
Berriman, G. B.; Good, J. C. Deelman, E.; Singh, G. Livny, M.
2009-09-01
Utility grids such as the Amazon EC2 and Amazon S3 clouds offer computational and storage resources that can be used on-demand for a fee by compute- and data-intensive applications. The cost of running an application on such a cloud depends on the compute, storage and communication resources it will provision and consume. Different execution plans of the same application may result in significantly different costs. We studied via simulation the cost performance trade-offs of different execution and resource provisioning plans by creating, under the Amazon cloud fee structure, mosaics with the Montage image mosaic engine, a widely used data- and compute-intensive application. Specifically, we studied the cost of building mosaics of 2MASS data that have sizes of 1, 2 and 4 square degrees, and a 2MASS all-sky mosaic. These are examples of mosaics commonly generated by astronomers. We also study these trade-offs in the context of the storage and communication fees of Amazon S3 when used for long-term application data archiving. Our results show that by provisioning the right amount of storage and compute resources cost can be significantly reduced with no significant impact on application performance.
Material Properties Analysis of Structural Members in Pumpkin Balloons
NASA Technical Reports Server (NTRS)
Sterling, W. J.
2003-01-01
The efficient design, service-life qualification, and reliability predictions for lightweight aerospace structures require careful mechanical properties analysis of candidate structural materials. The demand for high-quality laboratory data is particularly acute when the candidate material or the structural design has little history. The pumpkin-shaped super-pressure balloon presents both challenges. Its design utilizes load members (tendons) extending from apex to base around the gas envelope to achieve a lightweight structure. The candidate tendon material is highly weight-efficient braided HM cord. Previous mechanical properties studies of Zylon have focused on fiber and yarn, and industrial use of the material in tensile applications is limited. For high-performance polymers, a carefully plamed and executed properties analysis scheme is required to ensure the data are relevant to the desired application. Because no directly-applicable testing standard was available, a protocol was developed based on guidelines fiom professional and industry organizations. Due to the liquid-crystalline nature of the polymer, the cord is very stiff, creeps very little, and does not yield. Therefore, the key material property for this application is the breaking strength. The pretension load and gauge length were found to have negligible effect on the measured breaking strength over the ranges investigated. Strain rate was found to have no effect on breaking strength, within the range of rates suggested by the standards organizations. However, at the lower rate more similar to ULDB operations, the strength was reduced. The breaking strength increased when the experiment temperature was decreased from ambient to 183K which is the lowest temperature ULDB is expected to experience. The measured strength under all test conditions was well below that resulting from direct scale-up of fiber strength based on the manufacturers data. This expected result is due to the effects of the braiding process and material ageing.
Chungkham, Holendro Singh; Ingre, Michael; Karasek, Robert; Westerlund, Hugo; Theorell, Töres
2013-01-01
To examine the factor structure and to evaluate the longitudinal measurement invariance of the demand-control-support questionnaire (DCSQ), using the Swedish Longitudinal Occupational Survey of Health (SLOSH). A confirmatory factor analysis (CFA) and multi-group confirmatory factor analysis (MGCFA) models within the framework of structural equation modeling (SEM) have been used to examine the factor structure and invariance across time. Four factors: psychological demand, skill discretion, decision authority and social support, were confirmed by CFA at baseline, with the best fit obtained by removing the item repetitive work of skill discretion. A measurement error correlation (0.42) between work fast and work intensively for psychological demands was also detected. Acceptable composite reliability measures were obtained except for skill discretion (0.68). The invariance of the same factor structure was established, but caution in comparing mean levels of factors over time is warranted as lack of intercept invariance was evident. However, partial intercept invariance was established for work intensively. Our findings indicate that skill discretion and decision authority represent two distinct constructs in the retained model. However removing the item repetitive work along with either work fast or work intensively would improve model fit. Care should also be taken while making comparisons in the constructs across time. Further research should investigate invariance across occupations or socio-economic classes.
Chungkham, Holendro Singh; Ingre, Michael; Karasek, Robert; Westerlund, Hugo; Theorell, Töres
2013-01-01
Objectives To examine the factor structure and to evaluate the longitudinal measurement invariance of the demand-control-support questionnaire (DCSQ), using the Swedish Longitudinal Occupational Survey of Health (SLOSH). Methods A confirmatory factor analysis (CFA) and multi-group confirmatory factor analysis (MGCFA) models within the framework of structural equation modeling (SEM) have been used to examine the factor structure and invariance across time. Results Four factors: psychological demand, skill discretion, decision authority and social support, were confirmed by CFA at baseline, with the best fit obtained by removing the item repetitive work of skill discretion. A measurement error correlation (0.42) between work fast and work intensively for psychological demands was also detected. Acceptable composite reliability measures were obtained except for skill discretion (0.68). The invariance of the same factor structure was established, but caution in comparing mean levels of factors over time is warranted as lack of intercept invariance was evident. However, partial intercept invariance was established for work intensively. Conclusion Our findings indicate that skill discretion and decision authority represent two distinct constructs in the retained model. However removing the item repetitive work along with either work fast or work intensively would improve model fit. Care should also be taken while making comparisons in the constructs across time. Further research should investigate invariance across occupations or socio-economic classes. PMID:23950957
3D holographic polymer photonic crystal for superprism application
NASA Astrophysics Data System (ADS)
Chen, Jiaqi; Jiang, Wei; Chen, Xiaonan; Wang, Li; Zhang, Sasa; Chen, Ray T.
2007-02-01
Photonic crystal based superprism offers a new way to design new optical components for beam steering and DWDM application. 3D photonic crystals are especially attractive as they could offer more control of the light beam based on the needs. A polygonal prism based holographic fabrication method has been demonstrated for a three-dimensional face-centered-cubic (FCC)-type submicron polymer photonic crystal using SU8 as the photo-sensitive material. Therefore antivibration equipment and complicated optical alignment system are not needed and the requirement for the coherence of the laser source is relaxed compared with the traditional holographic setup. By changing the top-cut prism structure, the polarization of the laser beam, the exposure and development conditions we can achieve different kinds of triclinic or orthorhombic photonic crystals on demand. Special fabrication treatments have been introduced to ensure the survivability of the fabricated large area (cm2) nano-structures. Scanning electron microscopy and diffraction results proved the good uniformity of the fabricated structures. With the proper design of the refraction prism we have achieved a partial bandgap for S+C band (1460-1565nm) in the [111] direction. The transmission and reflection spectra obtained by Fourier transform infrared spectroscopy (FTIR) are in good agreement with simulated band structure. The superprism effects around 1550nm wavelength for the fabricated 3D polymer photonic crystal have been theoretically calculated and such effects can be used for beam steering purpose.
Structural materials for Gen-IV nuclear reactors: Challenges and opportunities
NASA Astrophysics Data System (ADS)
Murty, K. L.; Charit, I.
2008-12-01
Generation-IV reactor design concepts envisioned thus far cater toward a common goal of providing safer, longer lasting, proliferation-resistant and economically viable nuclear power plants. The foremost consideration in the successful development and deployment of Gen-IV reactor systems is the performance and reliability issues involving structural materials for both in-core and out-of-core applications. The structural materials need to endure much higher temperatures, higher neutron doses and extremely corrosive environment, which are beyond the experience of the current nuclear power plants. Materials under active consideration for use in different reactor components include various ferritic/martensitic steels, austenitic stainless steels, nickel-base superalloys, ceramics, composites, etc. This paper presents a summary of various Gen-IV reactor concepts, with emphasis on the structural materials issues depending on the specific application areas. This paper also discusses the challenges involved in using the existing materials under both service and off-normal conditions. Tasks become increasingly complex due to the operation of various fundamental phenomena like radiation-induced segregation, radiation-enhanced diffusion, precipitation, interactions between impurity elements and radiation-produced defects, swelling, helium generation and so forth. Further, high temperature capability (e.g. creep properties) of these materials is a critical, performance-limiting factor. It is demonstrated that novel alloy and microstructural design approaches coupled with new materials processing and fabrication techniques may mitigate the challenges, and the optimum system performance may be achieved under much demanding conditions.
NASA Astrophysics Data System (ADS)
Ribeiro Neto, A.; Scott, C. A.; Lima, E. A.; Montenegro, S. M. G. L.; Cirilo, J. A.
2014-09-01
Water availability for a range of human uses will increasingly be affected by climate change, especially in the arid and semiarid tropics. The main objective of this study is to evaluate the infrastructure sufficiency in meeting water demand under climate-induced socio-hydrological transition in the Capibaribe River basin (CRB). The basin has experienced spatial and sectoral (agriculture-to-urban) reconfiguration of water demands. Human settlements that were once dispersed, relying on intermittent sources of surface water, are now larger and more spatially concentrated, which increases water-scarcity effects. Based on the application of linked hydrologic and water-resources models using precipitation and temperature projections of the IPCC SRES (Special Report: Emissions Scenarios) A1B scenario, a reduction in rainfall of 26.0% translated to streamflow reduction of 60.0%. We used simulations from four members of the HadCM3 (UK Met Office Hadley Centre) perturbed physics ensemble, in which a single model structure is used and perturbations are introduced to the physical parameterization schemes in the model (Chou et al., 2012). We considered that the change of the water availability in the basin in the future scenarios must drive the water management and the development of adaptation strategies that will manage the water demand. Several adaptive responses are considered, including water-loss reductions, wastewater collection and reuse, and rainwater collection cisterns, which together have potential to reduce future water demand by 23.0%. This study demonstrates the vulnerabilities of the infrastructure system during socio-hydrological transition in response to hydroclimatic and demand variabilities in the CRB and also indicates the differential spatial impacts and vulnerability of multiple uses of water to changes over time. The simulations showed that the measures proposed and the water from interbasin transfer project of the São Francisco River had a positive impact over the water supply in the basin, mainly for human use. Industry and irrigation will suffer impact unless other measures are implemented for demand control.
Roter, Debra L; Erby, Lori H; Larson, Susan; Ellington, Lee
2007-10-01
Health literacy deficits affect half the American patient population and are linked to poor health, ineffective disease management and high rates of hospitalization. Restricted literacy has also been linked with less satisfying medical visits and communication difficulties, particularly in terms of the interpersonal and informational aspects of care. Despite growing attention to these issues by researchers and policy makers, few studies have attempted to conceptualize and assess those aspects of dialogue that challenge persons with low literacy skills, i.e., the oral literacy demand within medical encounters. The current study uses videotapes and transcripts of 152 prenatal and cancer pretest genetic counseling sessions recorded with simulated clients to develop a conceptual framework to explore oral literacy demand and its consequences for medical interaction and related outcomes. Ninety-six prenatal and 81 cancer genetic counselors-broadly representative of the US National Society of Genetic Counselors-participated in the study. Key elements of the conceptual framework used to define oral literacy demand include: (1) use of unfamiliar technical terms; (2) general language complexity, reflected in the application of Microsoft Word grammar summary statistics to session transcripts; and, (3) structural characteristics of dialogue, including pacing, density, and interactivity. Genetic counselor outcomes include self-ratings of session satisfaction, informativeness, and development of rapport. The simulated clients rated their satisfaction with session communication, the counselor's effective use of nonverbal skills, and the counselor's affective demeanor during the session. Sessions with greater overall technical term use were longer and used more complex language reflected in readability indices and multi-syllabic vocabulary (measures averaging p<.05). Sessions with a high proportionate use of technical terms were characterized by shorter visits, high readability demand, slow speech speed, fewer and more dense counselor speaking turns and low interactivity (p<.05). The higher the use of technical terms, and the more dense and less interactive the dialogue, the less satisfied the simulated clients were and the lower their ratings were of counselors' nonverbal effectiveness and affective demeanor (all relationships p<.05). Counselors' self-ratings of informativeness were also inversely related to use of technical terms (p<.05). Just as print material can be made more reader-friendly and effective following established guidelines, the medical dialogue may also be made more patient-centered and meaningful by having providers monitor their vocabulary and language, as well as the structural characteristics of interaction, thereby lowering the literacy demand of routine medical dialogue. These consequences are important for all patients but may be even more so for patients with restricted literacy.
NASA Technical Reports Server (NTRS)
Crispell, C.
1978-01-01
Data for specific joint design, utilizing various combinations of bolt, nut and lubricants in typical structure of the shuttle booster rocket is obtained. Requirements of the structure performance criteria were to withstand temperatures of 260 C (500 F) and to provide a nut lubricant which would be compatible with sealants used in the joint. Cadmium plating and dry film lubricant meeting the requirements of MIL-L-8937 were the lubricants specified. In a follow up effort, cadmium plating and cetyl alcohol were further specified The materials for the bolt and nut combinations were MP35N and A-286. These materials demand a lubricant to be used to prevent galling of the thread when tightened and also to help reduce the scatter of clamping load in application.
NASA Astrophysics Data System (ADS)
Konishi, Akihito; Hirao, Yasukazu; Kurata, Hiroyuki; Kubo, Takashi
2013-12-01
The edge state, which is a peculiar magnetic state in zigzag-edged graphene nanoribbons (GNRs) originating from an electron-electron correlation in an edge-localized π-state, has promising applications for magnetic and spintronics devices and has attracted much attention of physicists, chemists, and engineers. For deeper understanding the edge state, precise fabrication of edge structures in GNRs has been highly demanded. We focus on [a.b]periacene, which are polycyclic aromatic hydrocarbons (PAHs) that have zigzag and armchair edges on molecular periphery, as a model compound for the understanding and actually prepare and characterize them. This review summarizes our recent studies on the origin of the edge state by investigating [a.b]periacene in terms of the relationship between the molecular structure and spin-localizing character.
Metallic Nanostructures Based on DNA Nanoshapes
Shen, Boxuan; Tapio, Kosti; Linko, Veikko; Kostiainen, Mauri A.; Toppari, Jari Jussi
2016-01-01
Metallic nanostructures have inspired extensive research over several decades, particularly within the field of nanoelectronics and increasingly in plasmonics. Due to the limitations of conventional lithography methods, the development of bottom-up fabricated metallic nanostructures has become more and more in demand. The remarkable development of DNA-based nanostructures has provided many successful methods and realizations for these needs, such as chemical DNA metallization via seeding or ionization, as well as DNA-guided lithography and casting of metallic nanoparticles by DNA molds. These methods offer high resolution, versatility and throughput and could enable the fabrication of arbitrarily-shaped structures with a 10-nm feature size, thus bringing novel applications into view. In this review, we cover the evolution of DNA-based metallic nanostructures, starting from the metallized double-stranded DNA for electronics and progress to sophisticated plasmonic structures based on DNA origami objects. PMID:28335274
Love, Tracy; Haist, Frank; Nicol, Janet; Swinney, David
2009-01-01
Using functional magnetic resonance imaging (fMRI), this study directly examined an issue that bridges the potential language processing and multi-modal views of the role of Broca’s area: the effects of task-demands in language comprehension studies. We presented syntactically simple and complex sentences for auditory comprehension under three different (differentially complex) task-demand conditions: passive listening, probe verification, and theme judgment. Contrary to many language imaging findings, we found that both simple and complex syntactic structures activated left inferior frontal cortex (L-IFC). Critically, we found activation in these frontal regions increased together with increased task-demands. Specifically, tasks that required greater manipulation and comparison of linguistic material recruited L-IFC more strongly; independent of syntactic structure complexity. We argue that much of the presumed syntactic effects previously found in sentence imaging studies of L-IFC may, among other things, reflect the tasks employed in these studies and that L-IFC is a region underlying mnemonic and other integrative functions, on which much language processing may rely. PMID:16881268
Global Tungsten Demand and Supply Forecast
NASA Astrophysics Data System (ADS)
Dvořáček, Jaroslav; Sousedíková, Radmila; Vrátný, Tomáš; Jureková, Zdenka
2017-03-01
An estimate of the world tungsten demand and supply until 2018 has been made. The figures were obtained by extrapolating from past trends of tungsten production from1905, and its demand from 1964. In addition, estimate suggestions of major production and investment companies were taken into account with regard to implementations of new projects for mining of tungsten or possible termination of its standing extraction. It can be assumed that tungsten supply will match demand by 2018. This suggestion is conditioned by successful implementation of new tungsten extraction projects, and full application of tungsten recycling methods.
An integrated communications demand model
NASA Astrophysics Data System (ADS)
Doubleday, C. F.
1980-11-01
A computer model of communications demand is being developed to permit dynamic simulations of the long-term evolution of demand for communications media in the U.K. to be made under alternative assumptions about social, economic and technological trends in British Telecom's business environment. The context and objectives of the project and the potential uses of the model are reviewed, and four key concepts in the demand for communications media, around which the model is being structured are discussed: (1) the generation of communications demand; (2) substitution between media; (3) technological convergence; and (4) competition. Two outline perspectives on the model itself are given.
Guo, Junjie; Lee, Jaekwang; Contescu, Cristian I.; ...
2014-11-13
Crown ethers, introduced by Pedersen1, are at their most basic level neutral rings constructed of oxygen atoms linked by two- or three-carbon chains. They have attracted special attention for their ability to selectively incorporate various atoms2 or molecules within the cavity formed by the ring3-6. This property has led to the use of crown ethers and their compounds in a wide range of chemical and biological applications7,8. However, crown ethers are typically highly flexible, frustrating efforts to rigidify them for many uses that demand higher binding affinity and selectivity9,10. In this Letter, we report atomic-resolution images of the same basicmore » structures of the original crown ethers embedded in graphene. This arrangement constrains the crown ethers to be rigid and planar and thus uniquely suited for the many applications that crown ethers are known for. First-principles calculations show that the close similarity of the structures seen in graphene with those of crown ether molecules also extends to their selectivity towards specific metal cations depending on the ring size. Atoms (or molecules) incorporated within the crown ethers in graphene offer a simple environment that can be easily and systematically probed and modeled. Thus, we expect that this discovery will introduce a new wave of investigations and applications of chemically functionalized graphene.« less
Macedo, Maria L R; de Oliveira, Caio F R; Costa, Poliene M; Castelhano, Elaine C; Silva-Filho, Marcio C
2015-01-01
The overwhelming demand for food requires the application of technology on field. An important issue that limits the productivity of crops is related to insect attacks. Hence, several studies have evaluated the application of different compounds to reduce the field losses, especially insecticide compounds from plant sources. Among them, plant protease inhibitors (PIs) have been studied in both basic and applied researches, displaying positive results in control of some insects. However, certain species are able to bypass the insecticide effects exerted by PIs. In this review, we disclosed the adaptive mechanisms showed by lepidopteran and coleopteran insects, the most expressive insect orders related to crop predation. The structural aspects involved in adaptation mechanisms are presented as well as the newest alternatives for pest control. The application of biotechnological tools in crop protection will be mandatory in agriculture, and it will be up to researchers to find the best candidates for effective control in long-term.
NASA Astrophysics Data System (ADS)
Chen, Zimin; Zhuo, Yi; Tu, Wenbin; Ma, Xuejin; Pei, Yanli; Wang, Chengxin; Wang, Gang
2017-06-01
Various kinds of materials have been developed as transparent conductors for applications in semiconductor optoelectronic devices. However, there is a bottleneck that transparent conductive materials lose their transparency at ultraviolet (UV) wavelengths and could not meet the demands for commercial UV device applications. In this work, textured indium tin oxide (ITO) is grown and its potential to be used at UV wavelengths is explored. It is observed that the pronounced Burstein-Moss effect could widen the optical bandgap of the textured ITO to 4.7 eV. The average transmittance in UVA (315 nm-400 nm) and UVB (280 nm-315 nm) ranges is as high as 94% and 74%, respectively. The excellent optical property of textured ITO is attributed to its unique structural property. The compatibility of textured ITO thin films to the device fabrication is demonstrated on 368-nm nitride-based light emitting diodes, and the enhancement of light output power by 14.8% is observed compared to sputtered ITO.
Bioinspired greigite magnetic nanocrystals: chemical synthesis and biomedicine applications
Feng, Mei; Lu, Yang; Yang, Yuan; Zhang, Meng; Xu, Yun-Jun; Gao, Huai-Ling; Dong, Liang; Xu, Wei-Ping; Yu, Shu-Hong
2013-01-01
Large scale greigite with uniform dimensions has stimulated significant demands for applications such as hyperthermia, photovoltaics, medicine and cell separation, etc. However, the inhomogeneity and hydrophobicity for most of the as prepared greigite crystals has limited their applications in biomedicine. Herein, we report a green chemical method utilizing β-cyclodextrin (β-CD) and polyethylene glycol (PEG) to synthesize bioinspired greigite (Fe3S4) magnetic nanocrystals (GMNCs) with similar structure and magnetic property of magnetosome in a large scale. β-CD and PEG is responsible to control the crystal phase and morphology, as well as to bound onto the surface of nanocrystals and form polymer layers. The GMNCs exhibit a transverse relaxivity of 94.8 mM−1s−1 which is as high as iron oxide nanocrystals, and an entrapment efficiency of 58.7% for magnetic guided delivery of chemotherapeutic drug doxorubicin. Moreover, enhanced chemotherapeutic treatment of mice tumor was obtained via intravenous injection of doxorubicin loaded GMNCs. PMID:24141204
Performance and cost analysis of a structured concrete thermocline thermal energy storage system
NASA Astrophysics Data System (ADS)
Strasser, Matthew N.
Increasing global energy demands and diminishing fossil fuel resources have raised increased interest in harvesting renewable energy resources. Solar energy is a promising candidate, as sufficient irradiance is incident to the Earth to supply the energy demands of all of its inhabitants. At the utility scale, concentrating solar power (CSP) plants provide the most cost-efficient method of harnessing solar energy for conversion to electrical energy. A major roadblock to the large-scale implementation of CSP plants is the lack of thermal energy storage (TES) that would allow the continued production of electricity during the absence of constant irradiance. Sensible heat TES has been suggested as the most viable form of TES for CSP plants. Two-tank fluid TES systems have been incorporated at several CSP plants, significantly enhancing the performance of the plants. A single-tank thermocline TES system, requiring a reduced liquid media volume, has been suggested as a cost-reducing alternative. Unfortunately, the packed-aggregate bed of such TES system introduces the issue of thermal ratcheting and rupture of the tank's walls. To address this issue, it has been suggested that structured concrete be used in place of the aggregate bed. Potential concrete mix designs have been developed and tested for this application. Finite-difference-based numeric models are used to study the performance of packed-bed and structured concrete thermocline TES systems. Optimized models are developed for both thermocline configurations. The packed-bed thermocline model is used to determine whether or not assuming constant fluid properties over a temperature range is an acceptable assumption. A procedure is developed by which the cost of two-tank and single-tank thermocline TES systems in the capacity range of 100-3000 MWhe can be calculated. System Advisory Model is used to perform life-cycle cost and performance analysis of a central receiver plant incorporating four TES scenarios: no TES, two-tank TES, packed-bed thermocline TES, and structured concrete thermocline TES. Conclusions are drawn as to which form of TES provides the most viable option. Finally, concrete specimens cast from the aforementioned mix designs are tested in the presence of molten solar salt, and their applicability as structured filler material is assessed.
NASA Astrophysics Data System (ADS)
Milanović, Veljko; Kasturi, Abhishek; Yang, James; Su, Yu Roger; Hu, Frank
2017-02-01
2D quasistatic (point-to-point) gimbal-less MEMS mirrors enable programmable, arbitrary control of laser beam position and velocity - up to their maximum limits. Hence, they provide the ability to track targets, point lasercom beams, and to scan uniform velocity lines over objects in laser imaging. They are becoming increasingly established in applications including 3D scanning, laser marking and 3D printing, biomedical imaging, communications, and LiDAR. With the increased utility in applications that demand larger mirror sizes and larger overall angle*diameter (θ*D) figures of merit, the technology is continuously pushed against its limit. As a result we have implemented mirrors with larger diameters including 5.0mm, 6.4mm, and 7.5mm, and have designed actuators with larger torque and angles to match the Θ*D demand. While the results have been very positive in certain application cases, a limitation for their more wide-spread use has been the relatively high susceptibility of large- θ*D mirrors to shock and vibrations. On the other hand, one of the challenges of MEMS mirrors of small diameters is their lower optical power tolerance simply due to their smaller area and heat removal ability. Although they can be operated at up to 2-3W of CW laser power, new developments in dynamic solid state lighting in e.g. headlights demand operation at up to 10W or beyond. In this work we study and present several package-level approaches to increase mechanical damping, shock robustness, and laser power tolerance. Specifically, we study back-filling of MEMS packages with different gases as well as with different (increased) pressures to control damping and in turn increase robustness and useable bandwidth. Additionally, we study the effects of specialized mechanical structures which were designed and fabricated to modify packages to significantly reduce volumes of space around moving structures. In their standard form and packaging the MEMS mirrors tested in this study typically measure quality factors of 75-100. Increases of pressure up to 50psi have shown relatively modest reductions of the overall quality factor to the 40-50 range. Backfilling of packages with heavier inert gasses such as Ar and SF6 results in lowering of the quality factor down to 20-30 range. Mechanical modifications of the package with special structures and reduced air-gap to the window yielded the best results, reducing the quality factor to 9-14. Combination of specialized packaging structures and gas backfill and pressure control could provide a very efficient heat transfer from the mirror and the desired near-critical damping, but has not been demonstrated yet. The increased performance does not change the compactness and low power consumption - the improved MEMS mirrors still consume <1mW. So far, designs with mirror sizes through 3.0mm diameter with increased damping have passed 500G shock tests. In terms of improved heat removal we have found that the packaging improvement greatly increased optical power tolerance of MEMS mirrors from few Watts of CW laser power to <10 Watts. The exact numbers for the upper limit are not yet available - in samples where the heat removing structure was added and air was replaced with Helium, our setup with 3 combined lasers was not able to damage any samples.
U.S. hardwood fiber demand and supply situation : globalization and structural change
Peter J. Ince; Irene Durbak
2005-01-01
This paper reviews demand and supply trends for hardwood fiber in the United States. The objective is to illustrate nationwide shifts in demand and supply and show how the hardwood pulpwood market reacts to those shifts at a regional level. Thus, the market situation is illustrated using an economic rationale, and trends are projected under assumptions about future...
Studies on omnidirectional enhancement of giga-hertz radiation by sub-wavelength plasma modulation
NASA Astrophysics Data System (ADS)
Fanrong, KONG; Qiuyue, NIE; Shu, LIN; Zhibin, WANG; Bowen, LI; Shulei, ZHENG; Binhao, JIANG
2018-01-01
The technology of radio frequency (RF) radiation intensification for radio compact antennas based on modulation and enhancement effects of sub-wavelength plasma structures represents an innovative developing strategy. It exhibits important scientific significance and promising potential of broad applications in various areas of national strategic demands, such as electrical information network and microwave communication, detection and control technology. In this paper, laboratory experiments and corresponding analyses have been carried out to investigate the modulation and enhancement technology of sub-wavelength plasma structure on the RF electromagnetic radiation. An application focused sub-wavelength plasma-added intensification up to ∼7 dB higher than the free-space radiation is observed experimentally in giga-hertz (GHz) RF band. The effective radiation enhancement bandwidth covers from 0.85 to 1.17 GHz, while the enhanced electromagnetic signals transmitted by sub-wavelength plasma structures maintain good communication quality. Particularly, differing from the traditional RF electromagnetic radiation enhancement method characterized by focusing the radiation field of antenna in a specific direction, the sub-wavelength plasma-added intensification of the antenna radiation presents an omnidirectional enhancement, which is reported experimentally for the first time. Corresponding performance characteristics and enhancement mechanism analyses are also conducted in this paper. The results have demonstrated the feasibility and promising potential of sub-wavelength plasma modulation in application focused RF communication, and provided the scientific basis for further research and development of sub-wavelength plasma enhanced compact antennas with wide-range requests and good quality for communication.
Zinc Fingers, TALEs, and CRISPR Systems: A Comparison of Tools for Epigenome Editing.
Waryah, Charlene Babra; Moses, Colette; Arooj, Mahira; Blancafort, Pilar
2018-01-01
The completion of genome, epigenome, and transcriptome mapping in multiple cell types has created a demand for precision biomolecular tools that allow researchers to functionally manipulate DNA, reconfigure chromatin structure, and ultimately reshape gene expression patterns. Epigenetic editing tools provide the ability to interrogate the relationship between epigenetic modifications and gene expression. Importantly, this information can be exploited to reprogram cell fate for both basic research and therapeutic applications. Three different molecular platforms for epigenetic editing have been developed: zinc finger proteins (ZFs), transcription activator-like effectors (TALEs), and the system of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) and CRISPR-associated (Cas) proteins. These platforms serve as custom DNA-binding domains (DBDs), which are fused to epigenetic modifying domains to manipulate epigenetic marks at specific sites in the genome. The addition and/or removal of epigenetic modifications reconfigures local chromatin structure, with the potential to provoke long-lasting changes in gene transcription. Here we summarize the molecular structure and mechanism of action of ZF, TALE, and CRISPR platforms and describe their applications for the locus-specific manipulation of the epigenome. The advantages and disadvantages of each platform will be discussed with regard to genomic specificity, potency in regulating gene expression, and reprogramming cell phenotypes, as well as ease of design, construction, and delivery. Finally, we outline potential applications for these tools in molecular biology and biomedicine and identify possible barriers to their future clinical implementation.
Evaluation and comparison of a lightweight bamboo composite
NASA Astrophysics Data System (ADS)
Loth, Andreas; Berwing, Michael; Förster, Ralf
2016-10-01
The demand for fast changing production lines and other facilities needs new lightweight and stable systems for partitioning walls. There is also a need for ecological products for this application. The wood like grass bamboo provides a wide potential to substitute conventional wood. A composite lightweight honeycomb like bamboo board was developed and compared with reinforced and unreinforced plywood specimen. The acquired mechanical properties gave a promising result for the usability of bamboo as basis material for wide span boards. It can be manufactured with minimal technical investments, that suits also well for regions with little industry. The ecological assessment of the structure is very positive.
Hubble, Matthew J W
2002-09-01
Bone grafts are used in musculoskeletal surgery to restore structural integrity and enhance osteogenic potential. The demand for bone graft for skeletal reconstruction in bone tumor, revision arthroplasty, and trauma surgery, couple with recent advances in understanding and application of the biology of bone transplantation, has resulted in an exponential increase in the number of bone-grafting procedures performed over the last decade. It is estimated that 1.5 million bone-grafting procedures are currently performed worldwide each year, compared to a fraction of that number 20 years ago. Major developments also have resulted in the harvesting, storage, and use of bone grafts and production of graft derivatives, substitutes, and bone-inducing agents.
Discrete Fourier Transform in a Complex Vector Space
NASA Technical Reports Server (NTRS)
Dean, Bruce H. (Inventor)
2015-01-01
An image-based phase retrieval technique has been developed that can be used on board a space based iterative transformation system. Image-based wavefront sensing is computationally demanding due to the floating-point nature of the process. The discrete Fourier transform (DFT) calculation is presented in "diagonal" form. By diagonal we mean that a transformation of basis is introduced by an application of the similarity transform of linear algebra. The current method exploits the diagonal structure of the DFT in a special way, particularly when parts of the calculation do not have to be repeated at each iteration to converge to an acceptable solution in order to focus an image.
The approach to engineering tasks composition on knowledge portals
NASA Astrophysics Data System (ADS)
Novogrudska, Rina; Globa, Larysa; Schill, Alexsander; Romaniuk, Ryszard; Wójcik, Waldemar; Karnakova, Gaini; Kalizhanova, Aliya
2017-08-01
The paper presents an approach to engineering tasks composition on engineering knowledge portals. The specific features of engineering tasks are highlighted, their analysis makes the basis for partial engineering tasks integration. The formal algebraic system for engineering tasks composition is proposed, allowing to set the context-independent formal structures for engineering tasks elements' description. The method of engineering tasks composition is developed that allows to integrate partial calculation tasks into general calculation tasks on engineering portals, performed on user request demand. The real world scenario «Calculation of the strength for the power components of magnetic systems» is represented, approving the applicability and efficiency of proposed approach.
A microspectrometer based on subwavelength metal nanohole array
NASA Astrophysics Data System (ADS)
Cui, Jun; Xia, Liangping; Yang, Zheng; Yin, Lu; Zheng, Guoxing; Yin, Shaoyun; Du, Chunlei
2014-11-01
Catering to the active demand of the miniaturization of spectrometers, a simple microspectrometer with small size and light weight is presented in this paper. The presented microspectrometer is a typical filter-based spectrometer using the extraordinary optical transmission property of subwavelength metal hole array structure. Different subwavelength metal nanohole arrays are designed to work as different filter units obtained by changing the lattice parameters. By processing the filter spectra with a unique algorithm based on sparse representation, the proposed spectrometer is demonstrated to have the capability of high spectral resolution and accuracy. Benefit for the thin filmed feature, the microspectrometer is expected to find its application in integrated optical systems.
High-throughput SRCD using multi-well plates and its applications
NASA Astrophysics Data System (ADS)
Hussain, Rohanah; Jávorfi, Tamás; Rudd, Timothy R.; Siligardi, Giuliano
2016-12-01
The sample compartment for high-throughput synchrotron radiation circular dichroism (HT-SRCD) has been developed to satisfy an increased demand of protein characterisation in terms of folding and binding interaction properties not only in the traditional field of structural biology but also in the growing research area of material science with the potential to save time by 80%. As the understanding of protein behaviour in different solvent environments has increased dramatically the development of novel functions such as recombinant proteins modified to have different functions from harvesting solar energy to metabolonics for cleaning heavy and metal and organic molecule pollutions, there is a need to characterise speedily these system.
Hurley, J; Linsley, P
2007-09-01
This paper aims to highlight both the necessity, and the way forward for mental health nursing to integrate proposed legislative roles into practice. Argued is that community mental health nursing, historically absent from active participation within mental health law in the UK, is faced with new and demanding roles under proposed changes to the 1983 Mental Health Act of England and Wales. While supporting multidisciplinary training for such roles, the imperative of incorporating nursing specific values into consequent training programs is addressed through the offered educative framework. This framework explores the issues of power, ethics, legislative thematics and application to contemporary service structures.
NASA Astrophysics Data System (ADS)
Izadi, Arman; Kimiagari, Ali mohammad
2014-01-01
Distribution network design as a strategic decision has long-term effect on tactical and operational supply chain management. In this research, the location-allocation problem is studied under demand uncertainty. The purposes of this study were to specify the optimal number and location of distribution centers and to determine the allocation of customer demands to distribution centers. The main feature of this research is solving the model with unknown demand function which is suitable with the real-world problems. To consider the uncertainty, a set of possible scenarios for customer demands is created based on the Monte Carlo simulation. The coefficient of variation of costs is mentioned as a measure of risk and the most stable structure for firm's distribution network is defined based on the concept of robust optimization. The best structure is identified using genetic algorithms and 14% reduction in total supply chain costs is the outcome. Moreover, it imposes the least cost variation created by fluctuation in customer demands (such as epidemic diseases outbreak in some areas of the country) to the logistical system. It is noteworthy that this research is done in one of the largest pharmaceutical distribution firms in Iran.
NASA Astrophysics Data System (ADS)
Izadi, Arman; Kimiagari, Ali Mohammad
2014-05-01
Distribution network design as a strategic decision has long-term effect on tactical and operational supply chain management. In this research, the location-allocation problem is studied under demand uncertainty. The purposes of this study were to specify the optimal number and location of distribution centers and to determine the allocation of customer demands to distribution centers. The main feature of this research is solving the model with unknown demand function which is suitable with the real-world problems. To consider the uncertainty, a set of possible scenarios for customer demands is created based on the Monte Carlo simulation. The coefficient of variation of costs is mentioned as a measure of risk and the most stable structure for firm's distribution network is defined based on the concept of robust optimization. The best structure is identified using genetic algorithms and 14 % reduction in total supply chain costs is the outcome. Moreover, it imposes the least cost variation created by fluctuation in customer demands (such as epidemic diseases outbreak in some areas of the country) to the logistical system. It is noteworthy that this research is done in one of the largest pharmaceutical distribution firms in Iran.
The role of workaholism in the job demands-resources model.
Molino, Monica; Bakker, Arnold B; Ghislieri, Chiara
2016-07-01
The present study tries to gain more insight in workaholism by investigating its antecedents and consequences using the job demands-resources model. We hypothesized that job demands would be positively related to workaholism, particularly when job resources are low. In addition, we hypothesized that workaholism would be positively related to negative outcomes in three important life domains: health, family, and work. The research involved 617 Italian workers (employees and self-employed). To test the hypotheses we applied structural equation modeling (SEM) and moderated structural equation modeling (MSEM) using Mplus 6. The results of SEM showed a good model where workload, cognitive demands, emotional demands, and customer-related social stressors were positively related to workaholism and work-family conflict (WFC) (partial mediation). Additionally, workaholism was indirectly related to exhaustion and intentions to change jobs through WFC. Moreover, MSEM analyses confirmed that job resources (job security and opportunities for development) buffered the relationship between job demands and workaholism. Particularly, the interaction effects were statistically significant in five out of eight combinations. These findings suggest that workaholism is a function of a suboptimal work environment and predicts unfavorable employee outcomes. We discuss the theoretical and practical implications of these findings.
Technological hurdles to the application of intercalated graphite fibers
NASA Technical Reports Server (NTRS)
Gaier, James R.
1988-01-01
Before intercalated graphite fibers can be developed as an effective power material, there are several technological hurdles which must be overcome. These include the environmental stability, homogeneity and bulk properties, connection procedures, and costs. Strides were made within the last several years in stability and homogeneity of intercalated graphite fibers. Bulk properties and connection procedures are areas of active research now. Costs are still prohibitive for all but the most demanding applications. None of these problems, however, appear to be unsolvable, and their solution may result in wide spread GOC application. The development of a relatively simple technology application, such as EMI shielding, would stimulate the solution of scale-up problems. Once this technology is developed, then more demanding applications, such as power bus bars, may be possible.
blastjs: a BLAST+ wrapper for Node.js.
Page, Martin; MacLean, Dan; Schudoma, Christian
2016-02-27
To cope with the ever-increasing amount of sequence data generated in the field of genomics, the demand for efficient and fast database searches that drive functional and structural annotation in both large- and small-scale genome projects is on the rise. The tools of the BLAST+ suite are the most widely employed bioinformatic method for these database searches. Recent trends in bioinformatics application development show an increasing number of JavaScript apps that are based on modern frameworks such as Node.js. Until now, there is no way of using database searches with the BLAST+ suite from a Node.js codebase. We developed blastjs, a Node.js library that wraps the search tools of the BLAST+ suite and thus allows to easily add significant functionality to any Node.js-based application. blastjs is a library that allows the incorporation of BLAST+ functionality into bioinformatics applications based on JavaScript and Node.js. The library was designed to be as user-friendly as possible and therefore requires only a minimal amount of code in the client application. The library is freely available under the MIT license at https://github.com/teammaclean/blastjs.
Chu, Zonglin; Dreiss, Cécile A; Feng, Yujun
2013-09-07
A major scientific challenge of the past decade pertaining to the field of soft matter has been to craft 'adaptable' materials, inspired by nature, which can dynamically alter their structure and functionality on demand, in response to triggers produced by environmental changes. Amongst these, 'smart' surfactant wormlike micelles, responsive to external stimuli, are a particularly recent area of development, yet highly promising, given the versatility of the materials but simplicity of the design-relying on small amphiphilic molecules and their spontaneous self-assembly. The switching 'on' and 'off' of the micellar assembly structures has been reported using electrical, optical, thermal or pH triggers and is now envisaged for multiple stimuli. The structural changes, in turn, can induce major variations in the macroscopic characteristics, affecting properties such as viscosity and elasticity and sometimes even leading to a spontaneous and effective 'sol-gel' transition. These original smart materials based on wormlike micelles have been successfully used in the oil industry, and offer a significant potential in a wide range of other technological applications, including biomedicine, cleaning processes, drag reduction, template synthesis, to name but a few. This review will report results in this field published over the last few years, describe the potential and practical applications of stimuli-responsive wormlike micelles and point out future challenges.
Exploring Lithium Deficiency in Layered Oxide Cathode for Li-Ion Battery
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cho, Sung-Jin; Uddin, Md-Jamal; Alaboina, Pankaj K.
Abstract or short description: The ever-growing demand for high capacity cathode materials is on the rise since the futuristic applications are knocking on the door. Conventional approach to developing such cathode relies on the lithium-excess materials to operate the cathode at high voltage and extract more lithium-ion. Yet, they fail to satiate the needs because of their unresolved issues upon cycling such as, for lithium manganese-rich layered oxides – their voltage fading, and for as nickel-based layered oxides – the structural transition. Here, in contrast, lithium-deficient ratio is demonstrated as a new approach to attain high capacity at high voltagemore » for layered oxide cathodes. Rapid and cost effective lithiation of a porous hydroxide precursor with lithium deficient ratio acted as a driving force to partially convert the layered material to spinel phase yielding in a multiphase structure (MPS) cathode material. Upon cycling, MPS revealed structural stability at high voltage and high temperature and resulted in fast lithium-ion diffusion by providing a distinctive SEI chemistry – MPS displayed minimum lithium loss in SEI and formed a thinner SEI. MPS thus offer high energy and high power applications and provides a new perspective compared to the conventional layered cathode materials denying the focus for lithium excess material.« less
Scalable transfer of vertical graphene nanosheets for flexible supercapacitor applications
NASA Astrophysics Data System (ADS)
Sahoo, Gopinath; Ghosh, Subrata; Polaki, S. R.; Mathews, Tom; Kamruddin, M.
2017-10-01
Vertical graphene nanosheets (VGN) are the material of choice for application in next-generation electronic devices. The growing demand for VGN-based flexible devices for the electronics industry brings in restriction on VGN growth temperature. The difficulty associated with the direct growth of VGN on flexible substrates can be overcome by adopting an effective strategy of transferring the well-grown VGN onto arbitrary flexible substrates through a soft chemistry route. In the present study, we report an inexpensive and scalable technique for the polymer-free transfer of VGN onto arbitrary substrates without disrupting its morphology, structure, and properties. After transfer, the morphology, chemical structure, and electrical properties are analyzed by scanning electron microscopy, Raman spectroscopy, x-ray photoelectron spectroscopy, and four-probe resistive methods, respectively. The wetting properties are studied from the water contact angle measurements. The observed results indicate the retention of morphology, surface chemistry, structure, and electronic properties. Furthermore, the storage capacity of the transferred VGN-based binder-free and current collector-free flexible symmetric supercapacitor device is studied. A very low sheet resistance of 670 Ω/□ and excellent supercapacitance of 158 μF cm-2 with 86% retention after 10 000 cycles show the prospect of the damage-free VGN transfer approach for the fabrication of flexible nanoelectronic devices.
NASA Astrophysics Data System (ADS)
Tajbakhsh, Mahmood; Kariminasab, Mohaddeseh; Ganji, Masoud Darvish; Alinezhad, Heshmatollah
2017-12-01
Organic solar cells, especially bulk hetero-junction polymer solar cells (PSCs), are the most successful structures for applications in renewable energy. The dramatic improvement in the performance of PSCs has increased demand for new conjugated polymer donors and fullerene derivative acceptors. In the present study, quantum chemical calculations were performed for several representative fullerene derivatives in order to determine their frontier orbital energy levels and electronic structures, thereby helping to enhance their performance in PSC devices. We found correlations between the theoretical lowest unoccupied molecular orbital levels and electrophilicity index of various fullerenes with the experimental open circuit voltage of photovoltaic devices according to the poly(3-hexylthiophene) (P3HT):fullerene blend. The correlations between the structure and descriptors may facilitate screening of the best fullerene acceptor for the P3HT donor. Thus, we considered fullerenes with new functional groups and we predicted the output factors for the corresponding P3HT:fullerene blend devices. The results showed that fullerene derivatives based on thieno-o-quinodimethane-C60 with a methoxy group will have enhanced photovoltaic properties. Our results may facilitate the design of new fullerenes and the development of favorable acceptors for use in photovoltaic applications.
Optimal cube-connected cube multiprocessors
NASA Technical Reports Server (NTRS)
Sun, Xian-He; Wu, Jie
1993-01-01
Many CFD (computational fluid dynamics) and other scientific applications can be partitioned into subproblems. However, in general the partitioned subproblems are very large. They demand high performance computing power themselves, and the solutions of the subproblems have to be combined at each time step. The cube-connect cube (CCCube) architecture is studied. The CCCube architecture is an extended hypercube structure with each node represented as a cube. It requires fewer physical links between nodes than the hypercube, and provides the same communication support as the hypercube does on many applications. The reduced physical links can be used to enhance the bandwidth of the remaining links and, therefore, enhance the overall performance. The concept and the method to obtain optimal CCCubes, which are the CCCubes with a minimum number of links under a given total number of nodes, are proposed. The superiority of optimal CCCubes over standard hypercubes was also shown in terms of the link usage in the embedding of a binomial tree. A useful computation structure based on a semi-binomial tree for divide-and-conquer type of parallel algorithms was identified. It was shown that this structure can be implemented in optimal CCCubes without performance degradation compared with regular hypercubes. The result presented should provide a useful approach to design of scientific parallel computers.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shah, S.; Ghosh, K.; Jejurikar, S.
Graphical abstract: - Highlights: • Investigation of ground state energy in single and multi-layered InAs/GaAs QD. • Strain reducing layer (InGaAs) prevents the formation of non-radiative. • Strain reducing layer (InGaAs) is responsible for high activation energy. • Significant deviation from the Varshni model, E(T) = E − αT{sup 2}/T + β. - Abstract: Vertically coupled, multilayered InAs/GaAs quantum dots (QDs) covered with thin InGaAs strain-reducing layers (SRLs) are in demand for various technological applications. We investigated low temperature photoluminescence of single and multilayered structures in which the SRL thickness was varied. The SRL layer was responsible for high activationmore » energies. Deviation of experimental data from the Varshni (1967) model, E(T) = E − ∞ T{sup 2}/T + β, suggests that the InAs-layered QDs have properties different from those in bulk material. Anomalous ground-state peak linewidths (FWHM), especially for annealed multilayer structures, were observed. A ground-state peak blue-shift with a broadened linewidth was also observed. Loss of intensity was detected in samples annealed at 800 °C. Presence of SRLs prevents formation of non-radiative centers under high temperature annealing. The results indicate the potential importance of such structures in optoelectronic applications.« less
A Location Based Communication Proposal for Disaster Crisis Management
NASA Astrophysics Data System (ADS)
Gülnerman, A. G.; Goksel, C.; Tezer, A.
2014-12-01
The most vital applications within urban applications under the title of Geographical Information system applications are Disaster applications. Especially, In Turkey the most occured disaster type Earthquakes impacts are hard to retain in urban due to greatness of area, data and effected resident or victim. Currently, communications between victims and institutions congested and collapsed, after disaster that results emergency service delay and so secondary death and desperation. To avoid these types of life loss, the communication should be established between public and institutions. Geographical Information System Technology is seen capable of data management techniques and communication tool. In this study, Life Saving Kiosk Modal Proposal designed as a communication tool based on GIS, after disaster, takes locational emegency demands, meets emergency demands over notification maps which is created by those demands,increase public solidarity by visualizing close emergency demanded area surrounded another one and gathers emergency service demanded institutions notifications and aims to increasethe capability of management. This design prosals' leading role is public. Increase in capability depends on public major contribution to disaster management by required communication infrastructure establishment. The aim is to propound public power instead of public despiration. Apart from general view of disaster crisis management approaches, Life Saving Kiosk Modal Proposal indicates preparedness and response phases within the disaster cycle and solve crisis management with the organization of design in preparedness phase, use in response phase. This resolution modal flow diagram is builded between public, communication tool (kiosk) amd response force. The software is included in communication tools whose functions, interface designs and user algorithms are provided considering the public participation. In this study, disaster crisis management with public participation and power use with data flow modal based on location is came up for discussion by comparing with the other available applications in manner of time, detail of data, required staff and expertise degree, data reality and data archive.
NASA Astrophysics Data System (ADS)
Bertazzon, Stefania
The present research focuses on the interaction of supply and demand of down-hill ski tourism in the province of Alberta. The main hypothesis is that the demand for skiing depends on the socio-economic and demographic characteristics of the population living in the province and outside it. A second, consequent hypothesis is that the development of ski resorts (supply) is a response to the demand for skiing. From the latter derives the hypothesis of a dynamic interaction between supply (ski resorts) and demand (skiers). Such interaction occurs in space, within a range determined by physical distance and the means available to overcome it. The above hypotheses implicitly define interactions that take place in space and evolve over time. The hypotheses are tested by temporal, spatial, and spatio-temporal regression models, using the best available data and the latest commercially available software. The main purpose of this research is to explore analytical techniques to model spatial, temporal, and spatio-temporal dynamics in the context of regional science. The completion of the present research has produced more significant contributions than was originally expected. Many of the unexpected contributions resulted from theoretical and applied needs arising from the application of spatial regression models. Spatial regression models are a new and largely under-applied technique. The models are fairly complex and a considerable amount of preparatory work is needed, prior to their specification and estimation. Most of this work is specific to the field of application. The originality of the solutions devised is increased by the lack of applications in the field of tourism. The scarcity of applications in other fields adds to their value for other applications. The estimation of spatio-temporal models has been only partially attained in the present research. This apparent limitation is due to the novelty and complexity of the analytical methods applied. This opens new directions for further work in the field of spatial analysis, in conjunction with the development of specific software.
Fundamentals of Atom Transfer Radical Polymerization
ERIC Educational Resources Information Center
Coessens, Veerle M. C.; Matyjaszewski, Krzysztof
2010-01-01
Today's market increasingly demands sophisticated materials for advanced technologies and high-value applications, such as nanocomposites, optoelectronic, or biomedical materials. Therefore, the demand for well-defined polymers with very specific molecular architecture and properties increases. Until recently, these kinds of polymers could only be…
The role of physiology in the development of golf performance.
Smith, Mark F
2010-08-01
The attainment of consistent high performance in golf requires effective physical conditioning that is carefully designed and monitored in accordance with the on-course demands the player will encounter. Appreciating the role that physiology plays in the attainment of consistent performance, and how a player's physicality can inhibit performance progression, supports the notion that the application of physiology is fundamental for any player wishing to excel in golf. With cardiorespiratory, metabolic, hormonal, musculoskeletal and nutritional demands acting on the golfer within and between rounds, effective physical screening of a player will ensure physiological and anatomical deficiencies that may influence performance are highlighted. The application of appropriate golf-specific assessment methods will ensure that physical attributes that have a direct effect on golf performance can be measured reliably and accurately. With the physical development of golf performance being achieved through a process of conditioning with the purpose of inducing changes in structural and metabolic functions, training must focus on foundation whole-body fitness and golf-specific functional strength and flexibility activities. For long-term player improvement to be effective, comprehensive monitoring will ensure the player reaches an optimal physical state at predetermined times in the competitive season. Through continual assessment of a player's physical attributes, training effectiveness and suitability, and the associated adaptive responses, key physical factors that may impact most on performance success can be determined.
Running Neuroimaging Applications on Amazon Web Services: How, When, and at What Cost?
Madhyastha, Tara M; Koh, Natalie; Day, Trevor K M; Hernández-Fernández, Moises; Kelley, Austin; Peterson, Daniel J; Rajan, Sabreena; Woelfer, Karl A; Wolf, Jonathan; Grabowski, Thomas J
2017-01-01
The contribution of this paper is to identify and describe current best practices for using Amazon Web Services (AWS) to execute neuroimaging workflows "in the cloud." Neuroimaging offers a vast set of techniques by which to interrogate the structure and function of the living brain. However, many of the scientists for whom neuroimaging is an extremely important tool have limited training in parallel computation. At the same time, the field is experiencing a surge in computational demands, driven by a combination of data-sharing efforts, improvements in scanner technology that allow acquisition of images with higher image resolution, and by the desire to use statistical techniques that stress processing requirements. Most neuroimaging workflows can be executed as independent parallel jobs and are therefore excellent candidates for running on AWS, but the overhead of learning to do so and determining whether it is worth the cost can be prohibitive. In this paper we describe how to identify neuroimaging workloads that are appropriate for running on AWS, how to benchmark execution time, and how to estimate cost of running on AWS. By benchmarking common neuroimaging applications, we show that cloud computing can be a viable alternative to on-premises hardware. We present guidelines that neuroimaging labs can use to provide a cluster-on-demand type of service that should be familiar to users, and scripts to estimate cost and create such a cluster.
Photovoltaic village power application: Assessment of the near-term market
NASA Technical Reports Server (NTRS)
Rosenblum, L.; Bifano, W. J.; Poley, W. A.; Scudder, L. R.
1978-01-01
The village power application represents a potential market for photovoltaics. The price of energy for photovoltaic systems was compared to that of utility line extensions and diesel generators. The potential domestic demand was defined in both the government and commercial sectors. The foreign demand and sources of funding for village power systems in the developing countries were also discussed briefly. It was concluded that a near term domestic market of at least 12 MW min and a foreign market of about 10 GW exists.
Photovoltaic water pumping applications: Assessment of the near-term market
NASA Technical Reports Server (NTRS)
Rosenblum, L.; Bifano, W. J.; Scudder, L. R.; Poley, W. A.; Cusick, J. P.
1978-01-01
Water pumping applications represent a potential market for photovoltaics. The price of energy for photovoltaic systems was compared to that of utility line extensions and diesel generators. The potential domestic demand was defined in the government, commercial/institutional and public sectors. The foreign demand and sources of funding for water pumping systems in the developing countries were also discussed briefly. It was concluded that a near term domestic market of at least 240 megawatts and a foreign market of about 6 gigawatts exist.
Klie, T; Pfundstein, T
2010-04-01
In times of demographic and social change, it is increasingly important to ensure the availability of care services to cover the growing demand. With the implementation of the German long-term insurance act in 1994, the responsibility of states and municipalities was maintained; however, given the long-term care legislation's market orientation and competition neutrality, the classic instruments for demand planning and supervision of infrastructure developments were lost. This leads to new challenges for states and municipalities: their conventional objective-oriented planning lacks professional and juridical legitimization. Calculations of requirements must relate to methodology and professional expertise. In order to exercise their influence on infrastructure development, instruments of demand planning other than subsidization are required. Using the example of Rheinland-Pfalz (Rhineland-Palatinate) and the newly implemented care structure planning, the concept of care monitoring is introduced, and instruments to influence infrastructure development are outlined.
Mao, Daoyong; Li, Qing; Bai, Ningning; Dong, Hongzhou; Li, Daikun
2018-01-15
A major challenge in bone tissue engineering is the development of biomimetic scaffolds which should simultaneously meet mechanical strength and pore structure requirements. Herein, we combined technologies of high concentration solvent casting, particulate leaching, and room temperature compression molding to prepare a novel poly(lactic acid)/ethyl cellulose/hydroxyapatite (PLA/EC/HA) scaffold. The functional, structural and mechanical properties of the obtained porous scaffolds were characterized. The results indicated that the PLA/EC/HA scaffolds at the 20wt% HA loading level showed optimal mechanical properties and desired porous structure. Its porosity, contact angle, compressive yield strength and weight loss after 56days were 84.28±7.04%, 45.13±2.40°, 1.57±0.09MPa and 4.77±0.32%, respectively, which could satisfy the physiological demands to guide bone regeneration. Thus, the developed scaffolds have potential to be used as a bone substitute material for bone tissue engineering application. Copyright © 2017. Published by Elsevier Ltd.
Moore, Christopher; Marchant, Thomas
2017-07-12
Reconstructive volumetric imaging permeates medical practice because of its apparently clear depiction of anatomy. However, the tell tale signs of abnormality and its delineation for treatment demand experts work at the threshold of visibility for hints of structure. Hitherto, a suitable assistive metric that chimes with clinical experience has been absent. This paper develops the complexity measure approximate entropy (ApEn) from its 1D physiological origin into a three-dimensional (3D) algorithm to fill this gap. The first 3D algorithm for this is presented in detail. Validation results for known test arrays are followed by a comparison of fan-beam and cone-beam x-ray computed tomography image volumes used in image guided radiotherapy for cancer. Results show the structural detail down to individual voxel level, the strength of which is calibrated by the ApEn process itself. The potential for application in machine assisted manual interaction and automated image processing and interrogation, including radiomics associated with predictive outcome modeling, is discussed.
NASA Astrophysics Data System (ADS)
Moore, Christopher; Marchant, Thomas
2017-08-01
Reconstructive volumetric imaging permeates medical practice because of its apparently clear depiction of anatomy. However, the tell tale signs of abnormality and its delineation for treatment demand experts work at the threshold of visibility for hints of structure. Hitherto, a suitable assistive metric that chimes with clinical experience has been absent. This paper develops the complexity measure approximate entropy (ApEn) from its 1D physiological origin into a three-dimensional (3D) algorithm to fill this gap. The first 3D algorithm for this is presented in detail. Validation results for known test arrays are followed by a comparison of fan-beam and cone-beam x-ray computed tomography image volumes used in image guided radiotherapy for cancer. Results show the structural detail down to individual voxel level, the strength of which is calibrated by the ApEn process itself. The potential for application in machine assisted manual interaction and automated image processing and interrogation, including radiomics associated with predictive outcome modeling, is discussed.
Effects of rare earth oxide additive on surface and tribological properties of polyimide composites
NASA Astrophysics Data System (ADS)
Pan, Zihe; Wang, Tianchang; Chen, Li; Idziak, Stefan; Huang, Zhaohui; Zhao, Boxin
2017-09-01
Rare earth oxide La2O3 microparticles-reinforced polyimide (PI) composites (La-PI-Cs) were fabricated, aiming to improve the tribological property of PI. Surface roughness, surface composition, bulk structure, friction force (Ff) and coefficient of friction (COF) at macro/micro preload, and anti-wear performances of La-PI-Cs were studied and compared with neat PI. With La2O3 microparticles, La-PI-Cs showed larger surface roughness, lower surface energy, and higher hydrophobicity than neat PI, and displayed beneficial layered structure different from the compact structure of PI. Owing to these advantages, La-PI-Cs were found to show a 70% reduction in Ff and COF, and a 30% reduction in wear rate, indicating significantly lowered friction and enhanced anti-wear properties after adding La2O3 microparticles. Our research findings demonstrated an easy and low cost method to fabricate polymer composites with low friction and high wear resistance, and help meet the demanding of polymer composites with high tribological performances in broaden applications.
Local field enhancement and thermoplasmonics in multimodal aluminum structures
NASA Astrophysics Data System (ADS)
Wiecha, Peter R.; Mennemanteuil, Marie-Maxime; Khlopin, Dmitry; Martin, Jérôme; Arbouet, Arnaud; Gérard, Davy; Bouhelier, Alexandre; Plain, Jérôme; Cuche, Aurélien
2017-07-01
Aluminum nanostructures have recently been at the focus of numerous studies due to their properties including oxidation stability and surface plasmon resonances covering the ultraviolet and visible spectral windows. In this article, we reveal a facet of this metal relevant for both plasmonic purposes and photothermal conversion. The field distribution of high-order plasmonic resonances existing in two-dimensional Al structures is studied by nonlinear photoluminescence microscopy in a spectral region where electronic interband transitions occur. The polarization sensitivity of the field intensity maps shows that the electric field concentration can be addressed and controlled on demand. We use a numerical tool based on the Green dyadic method to analyze our results and to simulate the absorbed energy that is locally converted into heat. The polarization-dependent temperature increase of the Al structures is experimentally quantitatively measured, and is in an excellent agreement with theoretical predictions. Our work highlights Al as a promising candidate for designing thermal nanosources integrated in coplanar geometries for thermally assisted nanomanipulation or biophysical applications.
Advances in recombinant protein expression for use in pharmaceutical research.
Assenberg, Rene; Wan, Paul T; Geisse, Sabine; Mayr, Lorenz M
2013-06-01
Protein production for structural and biophysical studies, functional assays, biomarkers, mechanistic studies in vitro and in vivo, but also for therapeutic applications in pharma, biotech and academia has evolved into a mature discipline in recent years. Due to the increased emphasis on biopharmaceuticals, the growing demand for proteins used for structural and biophysical studies, the impact of genomics technologies on the analysis of large sets of structurally diverse proteins, and the increasing complexity of disease targets, the interest in innovative approaches for the expression, purification and characterisation of recombinant proteins has steadily increased over the years. In this review, we summarise recent developments in the field of recombinant protein expression for research use in pharma, biotech and academia. We focus mostly on the latest developments for protein expression in the most widely used expression systems: Escherichia coli (E. coli), insect cell expression using the Baculovirus Expression Vector System (BEVS) and, finally, transient and stable expression of recombinant proteins in mammalian cells. Copyright © 2013. Published by Elsevier Ltd.
Energy Efficiency and Demand Response for Residential Applications
NASA Astrophysics Data System (ADS)
Wellons, Christopher J., II
The purpose of this thesis is to analyze the costs, feasibility and benefits of implementing energy efficient devices and demand response programs to a residential consumer environment. Energy efficiency and demand response are important for many reasons, including grid stabilization. With energy demand increasing, as the years' pass, the drain on the grid is going up. There are two key solutions to this problem, increasing supply by building more power plants and decreasing demand during peak periods, by increasing participation in demand response programs and by upgrading residential and commercial customers to energy efficient devices, to lower demand throughout the day. This thesis focuses on utilizing demand response methods and energy efficient device to reduce demand. Four simulations were created to analyze these methods. These simulations show the importance of energy efficiency and demand response participation to help stabilize the grid, integrate more alternative energy resources, and reduce emissions from fossil fuel generating facilities. The results of these numerical analyses show that demand response and energy efficiency can be beneficial to consumers and utilities. With demand response being the most beneficial to the utility and energy efficiency, specifically LED lighting, providing the most benefits to the consumer.
Multifuctional integrated sensors (MFISES).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Homeijer, Brian D.; Roozeboom, Clifton
2015-10-01
Many emerging IoT applications require sensing of multiple physical and environmental parameters for: completeness of information, measurement validation, unexpected demands, improved performance. For example, a typical outdoor weather station measures temperature, humidity, barometric pressure, light intensity, rainfall, wind speed and direction. Existing sensor technologies do not directly address the demand for cost, size, and power reduction in multi-paramater sensing applications. Industry sensor manufacturers have developed integrated sensor systems for inertial measurements that combine accelerometers, gyroscopes, and magnetometers, but do not address environmental sensing functionality. In existing research literature, a technology gap exists between the functionality of MEMS sensors and themore » real world applications of the sensors systems.« less
7 CFR 989.56 - Raisin diversion program.
Code of Federal Regulations, 2013 CFR
2013-01-01
... AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM GRAPES... review production data, supply data, demand data, including anticipated demand to all potential market... applicable to such diversion tonnage. A production cap of 2.75 tons of raisins per acre shall be established...
7 CFR 989.56 - Raisin diversion program.
Code of Federal Regulations, 2012 CFR
2012-01-01
... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM GRAPES... review production data, supply data, demand data, including anticipated demand to all potential market... applicable to such diversion tonnage. A production cap of 2.75 tons of raisins per acre shall be established...
7 CFR 989.56 - Raisin diversion program.
Code of Federal Regulations, 2010 CFR
2010-01-01
... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM GRAPES... review production data, supply data, demand data, including anticipated demand to all potential market... applicable to such diversion tonnage. A production cap of 2.75 tons of raisins per acre shall be established...
7 CFR 989.56 - Raisin diversion program.
Code of Federal Regulations, 2014 CFR
2014-01-01
... AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM GRAPES... review production data, supply data, demand data, including anticipated demand to all potential market... applicable to such diversion tonnage. A production cap of 2.75 tons of raisins per acre shall be established...
7 CFR 989.56 - Raisin diversion program.
Code of Federal Regulations, 2011 CFR
2011-01-01
... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM GRAPES... review production data, supply data, demand data, including anticipated demand to all potential market... applicable to such diversion tonnage. A production cap of 2.75 tons of raisins per acre shall be established...
Remote sensing inputs to water demand modeling
NASA Technical Reports Server (NTRS)
Estes, J. E.; Jensen, J. R.; Tinney, L. R.; Rector, M.
1975-01-01
In an attempt to determine the ability of remote sensing techniques to economically generate data required by water demand models, the Geography Remote Sensing Unit, in conjunction with the Kern County Water Agency of California, developed an analysis model. As a result it was determined that agricultural cropland inventories utilizing both high altitude photography and LANDSAT imagery can be conducted cost effectively. In addition, by using average irrigation application rates in conjunction with cropland data, estimates of agricultural water demand can be generated. However, more accurate estimates are possible if crop type, acreage, and crop specific application rates are employed. An analysis of the effect of saline-alkali soils on water demand in the study area is also examined. Finally, reference is made to the detection and delineation of water tables that are perched near the surface by semi-permeable clay layers. Soil salinity prediction, automated crop identification on a by-field basis, and a potential input to the determination of zones of equal benefit taxation are briefly touched upon.
Measuring the impact of final demand on global production system based on Markov process
NASA Astrophysics Data System (ADS)
Xing, Lizhi; Guan, Jun; Wu, Shan
2018-07-01
Input-output table is a comprehensive and detailed in describing the national economic systems, consisting of supply and demand information among various industrial sectors. The complex network, a theory and method for measuring the structure of complex system, can depict the structural properties of social and economic systems, and reveal the complicated relationships between the inner hierarchies and the external macroeconomic functions. This paper tried to measure the globalization degree of industrial sectors on the global value chain. Firstly, it constructed inter-country input-output network models to reproduce the topological structure of global economic system. Secondly, it regarded the propagation of intermediate goods on the global value chain as Markov process and introduced counting first passage betweenness to quantify the added processing amount when globally final demand stimulates this production system. Thirdly, it analyzed the features of globalization at both global and country-sector level
Cohn, Neil
2013-04-01
Narratives are an integral part of human expression. In the graphic form, they range from cave paintings to Egyptian hieroglyphics, from the Bayeux Tapestry to modern day comic books (Kunzle, 1973; McCloud, 1993). Yet not much research has addressed the structure and comprehension of narrative images, for example, how do people create meaning out of sequential images? This piece helps fill the gap by presenting a theory of Narrative Grammar. We describe the basic narrative categories and their relationship to a canonical narrative arc, followed by a discussion of complex structures that extend beyond the canonical schema. This demands that the canonical arc be reconsidered as a generative schema whereby any narrative category can be expanded into a node in a tree structure. Narrative "pacing" is interpreted as a reflection of various patterns of this embedding: conjunction, left-branching trees, center-embedded constituencies, and others. Following this, diagnostic methods are proposed for testing narrative categories and constituency. Finally, we outline the applicability of this theory beyond sequential images, such as to film and verbal discourse, and compare this theory with previous approaches to narrative and discourse. Copyright © 2012 Cognitive Science Society, Inc.
Structural and congenital heart disease interventions: the role of three-dimensional printing.
Meier, L M; Meineri, M; Qua Hiansen, J; Horlick, E M
2017-02-01
Advances in catheter-based interventions in structural and congenital heart disease have mandated an increased demand for three-dimensional (3D) visualisation of complex cardiac anatomy. Despite progress in 3D imaging modalities, the pre- and periprocedural visualisation of spatial anatomy is relegated to two-dimensional flat screen representations. 3D printing is an evolving technology based on the concept of additive manufacturing, where computerised digital surface renders are converted into physical models. Printed models replicate complex structures in tangible forms that cardiovascular physicians and surgeons can use for education, preprocedural planning and device testing. In this review we discuss the different steps of the 3D printing process, which include image acquisition, segmentation, printing methods and materials. We also examine the expanded applications of 3D printing in the catheter-based treatment of adult patients with structural and congenital heart disease while highlighting the current limitations of this technology in terms of segmentation, model accuracy and dynamic capabilities. Furthermore, we provide information on the resources needed to establish a hospital-based 3D printing laboratory.
Single-Walled Carbon Nanohorns for Energy Applications
Zhang, Zhichao; Han, Shuang; Wang, Chao; Li, Jianping; Xu, Guobao
2015-01-01
With the growth of the global economy and population, the demand for energy is increasing sharply. The development of environmentally a benign and reliable energy supply is very important and urgent. Single-walled carbon nanohorns (SWCNHs), which have a horn-shaped tip at the top of single-walled nanotube, have emerged as exceptionally promising nanomaterials due to their unique physical and chemical properties since 1999. The high purity and thermal stability, combined with microporosity and mesoporosity, high surface area, internal pore accessibility, and multiform functionalization make SWCNHs promising candidates in many applications, such as environment restoration, gas storage, catalyst support or catalyst, electrochemical biosensors, drug carrier systems, magnetic resonance analysis and so on. The aim of this review is to provide a comprehensive overview of SWCNHs in energy applications, including energy conversion and storage. The commonly adopted method to access SWCNHs, their structural modifications, and their basic properties are included, and the emphasis is on their application in different devices such as fuel cells, dye-sensitized solar cells, supercapacitors, Li-ion batteries, Li-S batteries, hydrogen storage, biofuel cells and so forth. Finally, a perspective on SWCNHs’ application in energy is presented. PMID:28347092
NASA Astrophysics Data System (ADS)
Shan, Ning
2016-10-01
Carbon fiber composite is widely applied to the field of aerospace engineering because of its excellent performance. But it will be able to form more defects in the process of manufacturing inevitably on account of unique manufacturing process. Meanwhile it has sophisticated structure and services in the bad environment long time. The existence of defects will be able to cause the sharp decline in component's performance when the defect accumulates to a certain degree. So the reliability and safety test demand of carbon fiber composite is higher and higher. Ultrasonic testing technology is the important means used for characteristics of component inspection of composite materials. Ultrasonic information detection uses acoustic transducer generally. It need coupling agent and is higher demand for the surface of sample. It has narrow frequency band and low test precision. The extrinsic type optical fiber F-P interference cavity structure is designed to this problem. Its optical interference model is studied. The initial length of F-P cavity is designed. The realtime online detection system of carbon fiber composite is established based on optical fiber F-P Ultrasound sensing technology. Finally, the testing experiment study is conducted. The results show that the system can realize real-time online detection of carbon fiber composite's defect effectively. It operates simply and realizes easily. It has low cost and is easy to practical engineering.
NASA Astrophysics Data System (ADS)
Setiawan, D.; Subhan, A.; Saptari, S. A.
2017-07-01
The necessity of high charge-discharge capacity lithium-ion battery becomes very urgent due to its applications demand. Several researches have been done to meet the demand including Ca doping on Li4Ti5O12 for anode material of lithium-ion batteries. Ca-doped Li4Ti5O12 (LTO) in the form of Li4-xCaxTi5O12 (x = 0, 0.05, 0.075, and 0.1) have been synthesized using simple solid state reaction. The materials preparation involved waste eggshells in the form of CaCO3 as Ca source. The structure and capacity of as-prepared samples were characterized using X-Ray Diffractometer and Cyclic Voltametry. X-Ray Diffractometer characterization revealed that all amount of dopant had entered the lattice structure of LTO successfully. The crystalline sizes were obtained by using Scherrer equation. No significant differences are detected in lattice parameters (˜8.35 Å) and crystalline sizes (˜27 nm) between all samples. Cyclic Voltametry characterization shows that Li4-xCaxTi5O12 (x = 0.05) has highest charge-discharge capacity of 177.14 mAh/g and 181.92 mAh/g, respectively. Redox-potentials of samples show no significant differences with the average of 1.589 V.
Work-family conflict in Japan: how job and home demands affect psychological distress.
Shimazu, Akihito; Bakker, Arnold B; Demerouti, Evangelia; Peeters, Maria C W
2010-01-01
The aim of the present study was to examine how job and home demands are related to psychological distress in a sample of Japanese working parents with preschool children (n=196). We expected that job and home demands are partially related to psychological distress through work-to-family conflict (WFC) and family-to-work conflict (FWC), respectively. Structural equation modeling showed that, as expected, home demands were partially related to psychological distress, both directly and indirectly through FWC. In contrast, job demands were only directly related to psychological distress. The differences between the roles of FWC and WFC are discussed using identity theory.
Estimation of the behavior factor of existing RC-MRF buildings
NASA Astrophysics Data System (ADS)
Vona, Marco; Mastroberti, Monica
2018-01-01
In recent years, several research groups have studied a new generation of analysis methods for seismic response assessment of existing buildings. Nevertheless, many important developments are still needed in order to define more reliable and effective assessment procedures. Moreover, regarding existing buildings, it should be highlighted that due to the low knowledge level, the linear elastic analysis is the only analysis method allowed. The same codes (such as NTC2008, EC8) consider the linear dynamic analysis with behavior factor as the reference method for the evaluation of seismic demand. This type of analysis is based on a linear-elastic structural model subject to a design spectrum, obtained by reducing the elastic spectrum through a behavior factor. The behavior factor (reduction factor or q factor in some codes) is used to reduce the elastic spectrum ordinate or the forces obtained from a linear analysis in order to take into account the non-linear structural capacities. The behavior factors should be defined based on several parameters that influence the seismic nonlinear capacity, such as mechanical materials characteristics, structural system, irregularity and design procedures. In practical applications, there is still an evident lack of detailed rules and accurate behavior factor values adequate for existing buildings. In this work, some investigations of the seismic capacity of the main existing RC-MRF building types have been carried out. In order to make a correct evaluation of the seismic force demand, actual behavior factor values coherent with force based seismic safety assessment procedure have been proposed and compared with the values reported in the Italian seismic code, NTC08.
Amagasa, Takashi; Nakayama, Takeo
2012-07-01
To test the hypothesis that relationship reported between long working hours and depression was inconsistent in previous studies because job demand was treated as a confounder. Structural equation modeling was used to construct five models, using work-related factors and depressive mood scale obtained from 218 clerical workers, to test for goodness of fit and was externally validated with data obtained from 1160 sales workers. Multiple logistic regression analysis was also performed. The model that showed that long working hours increased depression risk when job demand was regarded as an intermediate variable was the best fitted model (goodness-of-fit index/root-mean-square error of approximation: 0.981 to 0.996/0.042 to 0.044). The odds ratio for depression risk with work that was high demand and 60 hours or more per week was estimated at 2 to 4 versus work that was low demand and less than 60 hours per week. Long working hours increased depression risk, with job demand being an intermediate variable.
Enhancing Price Response Programs through Auto-DR: California's 2007 Implementation Experience
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kiliccote, Sila; Wikler, Greg; Chiu, Albert
2007-12-18
This paper describes automated demand response (Auto-DR) activities, an innovative effort in California to ensure that DR programs produce effective and sustainable impacts. Through the application of automation and communication technologies coupled with well-designed incentives and DR programs such as Critical Peak Pricing (CPP) and Demand Bidding (DBP), Auto-DR is opening up the opportunity for many different types of buildings to effectively participate in DR programs. We present the results of Auto-DR implementation efforts by the three California investor-owned utilities for the Summer of 2007. The presentation emphasizes Pacific Gas and Electric Company's (PG&E) Auto-DR efforts, which represents the largestmore » in the state. PG&E's goal was to recruit, install, test and operate 15 megawatts of Auto-DR system capability. We describe the unique delivery approaches, including optimizing the utility incentive structures designed to foster an Auto-DR service provider community. We also show how PG&E's Critical Peak Pricing (CPP) and Demand Bidding (DBP) options were called and executed under the automation platform. Finally, we show the results of the Auto-DR systems installed and operational during 2007, which surpassed PG&E's Auto-DR goals. Auto-DR is being implemented by a multi-disciplinary team including the California Investor Owned Utilities (IOUs), energy consultants, energy management control system vendors, the Lawrence Berkeley National Laboratory (LBNL), and the California Energy Commission (CEC).« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Micheletti, Tatiane, E-mail: micheletti@forst.tu-dresden.de; Jost, François; Berger, Uta
Although the importance of ecosystem services provided by natural forests, especially mangroves, is well known, the destruction of these environments is still ubiquitous and therefore protection measures are urgently needed. The present study compares the current approach of economic valuation of ecosystem services to a proposed one, using a study case of a mangrove system as an example. We suggest that a cost-benefit analysis for economically valuing environmental services should be performed with three additional modifications consisting of (i) a categorization of local stakeholders as demanders of particular ecosystem services, (ii) acknowledgement of the government as one of these demandermore » groups, and (iii) the inclusion of opportunity costs in the valuation. The application of this approach to the mangrove area in the east portion of Great Abaco Island, the Bahamas, reveals that not only the ecosystem services received differ between demander groups, but the monetary benefits and costs are also specific to each of these groups. We show that the economic valuation of the ecosystem should be differentiated for each category, instead of being calculated as a net ‘societal value’ as it is currently. Applying this categorization of demanders enables a better understanding of the cost and benefit structure of the protection of a natural area. The present paper aims to facilitate discussions regarding benefit and cost sharing related to the protection of natural areas.« less
Legumes as Functional Ingredients in Gluten-Free Bakery and Pasta Products.
Foschia, Martina; Horstmann, Stefan W; Arendt, Elke K; Zannini, Emanuele
2017-02-28
The increasing demand for gluten-free food products from consumers has triggered food technologists to investigate a wide range of gluten-free ingredients from different sources to reproduce the unique network structure developed by gluten in a wheat-dough system. In recent times, the attention has been focused on novel application of legume flour or ingredients. The interest in this crop category is mainly attributed to their functional properties, such as solubility and water-binding capacity, which play an important role in gluten-free food formulation and processing. Their nutritional profile may also counteract the lack of nutrients commonly highlighted in commercial gluten-free bakery and pasta products, providing valuable sources of protein, dietary fiber, vitamins, minerals, and complex carbohydrates, which in turn have a positive impact on human health. This review reports the main chemical and functional characteristics of legumes and their functional application in gluten-free products.
Through-wafer interrogation of microstructure motion for MEMS feedback control
NASA Astrophysics Data System (ADS)
Dawson, Jeremy M.; Chen, Jingdong; Brown, Kolin S.; Famouri, Parviz F.; Hornak, Lawrence A.
1999-09-01
Closed-loop MEMS control enables mechanical microsystems to adapt to the demands of the environment which they are actuating opening a new window of opportunity for future MEMS applications. Planar diffractive optical microsystems have the potential to enable the integrated optical interrogation of MEMS microstructure position fully decoupled from the means of mechanical actuation which is central to realization of feedback control. This paper presents the results of initial research evaluating through-wafer optical microsystems for MEMS integrated optical monitoring. Positional monitoring results obtained from a 1.3 micrometer wavelength through- wafer free-space optical probe of a lateral comb resonator fabricated using the Multi-User MEMS Process Service (MUMPS) are presented. Given the availability of positional information via probe signal feedback, a simulation of the application of nonlinear sliding control is presented illustrating position control of the lateral comb resonator structure.
Matthies, H K; Walter, G F; Brandis, A; Stan, A C; Ammann, A; von Jan, U; Porth, A J
1999-01-01
The combination of new and rapidly developing interactive multimedia computers and applications with electronic networks will require a restructuring of our traditional approach to strategic planning and organizational structure. Worldwide telecommunication networks (using satellites, cable) are now facilitating the global pooling of healthcare information and medical knowledge independent of location. The development of multimedia information and communication systems demands cooperative working teams of authors, who are able to master several areas of medical knowledge as well as the presentation of these in different multimedia forms. The assemblage of telematics and services offers a base for multimedia applications, for example teleteaching, telelearning, telepublishing, teleconsulting, teleconferencing, telemedicine etc. The expansion of the internet will also lead to the formation of interdisciplinary "Global Education Networks". The theory and practice of education are undergoing dramatic changes. Lifelong learning and adaptation of medical practice to new knowledge and new techniques will be even more important in the future.
Recent progress of flexible and wearable strain sensors for human-motion monitoring
NASA Astrophysics Data System (ADS)
Ge, Gang; Huang, Wei; Shao, Jinjun; Dong, Xiaochen
2018-01-01
With the rapid development of human artificial intelligence and the inevitably expanding markets, the past two decades have witnessed an urgent demand for the flexible and wearable devices, especially the flexible strain sensors. Flexible strain sensors, incorporated the merits of stretchability, high sensitivity and skin-mountable, are emerging as an extremely charming domain in virtue of their promising applications in artificial intelligent realms, human-machine systems and health-care devices. In this review, we concentrate on the transduction mechanisms, building blocks of flexible physical sensors, subsequently property optimization in terms of device structures and sensing materials in the direction of practical applications. Perspectives on the existing challenges are also highlighted in the end. Project supported by the NNSF of China (Nos. 61525402, 61604071), the Key University Science Research Project of Jiangsu Province (No. 15KJA430006), and the Natural Science Foundation of Jiangsu Province (No. BK20161012).
Conducting Polymers in the Fields of Energy, Environmental Remediation, and Chemical-Chiral Sensors.
Ibanez, Jorge G; Rincón, Marina E; Gutierrez-Granados, Silvia; Chahma, M'hamed; Jaramillo-Quintero, Oscar A; Frontana-Uribe, Bernardo A
2018-05-09
Conducting polymers (CPs), thanks to their unique properties, structures made on-demand, new composite mixtures, and possibility of deposit on a surface by chemical, physical, or electrochemical methodologies, have shown in the last years a renaissance and have been widely used in important fields of chemistry and materials science. Due to the extent of the literature on CPs, this review, after a concise introduction about the interrelationship between electrochemistry and conducting polymers, is focused exclusively on the following applications: energy (energy storage devices and solar cells), use in environmental remediation (anion and cation trapping, electrocatalytic reduction/oxidation of pollutants on CP based electrodes, and adsorption of pollutants) and finally electroanalysis as chemical sensors in solution, gas phase, and chiral molecules. This review is expected to be comprehensive, authoritative, and useful to the chemical community interested in CPs and their applications.
Novel bamboo structured TiO2 nanotubes for energy storage/production applications
NASA Astrophysics Data System (ADS)
Samuel, J. J.; Beh, K. P.; Cheong, Y. L.; Yusuf, W. A. A.; Yam, F. K.
2018-04-01
Nanostructured TiO2 received much attention owing to its high surface-to-volume ratio, which can be advantageous in energy storage and production applications. However, the increase in energy consumption at present and possibly the foreseeable future has demanded energy storage and production devices of even higher performance. A direct approach would be manipulating the physical aspects of TiO2 nanostructures, particularly, nanotubes. In this work, dual voltage anodization system has been implemented to fabricate bamboo shaped TiO2 nanotubes, which offers even greater surface area. This unique nanostructure would be used in Dye Sensitized Solar Cell (DSSC) fabrication and its performance will be evaluated and compared along other forms of TiO2 nanotubes. The results showed that bamboo shaped nanotubes indeed are superior morphologically, with an increase of efficiency of 107% at 1.130% efficiency when compared to smooth walled nanotubes at 0.546% efficiency.
Extending Strong Scaling of Quantum Monte Carlo to the Exascale
NASA Astrophysics Data System (ADS)
Shulenburger, Luke; Baczewski, Andrew; Luo, Ye; Romero, Nichols; Kent, Paul
Quantum Monte Carlo is one of the most accurate and most computationally expensive methods for solving the electronic structure problem. In spite of its significant computational expense, its massively parallel nature is ideally suited to petascale computers which have enabled a wide range of applications to relatively large molecular and extended systems. Exascale capabilities have the potential to enable the application of QMC to significantly larger systems, capturing much of the complexity of real materials such as defects and impurities. However, both memory and computational demands will require significant changes to current algorithms to realize this possibility. This talk will detail both the causes of the problem and potential solutions. Sandia National Laboratories is a multi-mission laboratory managed and operated by Sandia Corp, a wholly owned subsidiary of Lockheed Martin Corp, for the US Department of Energys National Nuclear Security Administration under contract DE-AC04-94AL85000.
Recent Advances on Carbon Nanotubes and Graphene Reinforced Ceramics Nanocomposites
Ahmad, Iftikhar; Yazdani, Bahareh; Zhu, Yanqiu
2015-01-01
Ceramics suffer the curse of extreme brittleness and demand new design philosophies and novel concepts of manufacturing to overcome such intrinsic drawbacks, in order to take advantage of most of their excellent properties. This has been one of the foremost challenges for ceramic material experts. Tailoring the ceramics structures at nanometre level has been a leading research frontier; whilst upgrading via reinforcing ceramic matrices with nanomaterials including the latest carbon nanotubes (CNTs) and graphene has now become an eminent practice for advanced applications. Most recently, several new strategies have indeed improved the properties of the ceramics/CNT nanocomposites, such as by tuning with dopants, new dispersions routes and modified sintering methods. The utilisation of graphene in ceramic nanocomposites, either as a solo reinforcement or as a hybrid with CNTs, is the newest development. This article will summarise the recent advances, key difficulties and potential applications of the ceramics nanocomposites reinforced with CNTs and graphene. PMID:28347001
Wang, Guan-E; Wang, Ming-Sheng; Cai, Li-Zhen; Li, Wen-Hua
2015-01-01
Single-component white light materials may create great opportunities for novel conventional lighting applications and display systems; however, their reported color rendering index (CRI) values, one of the key parameters for lighting, are less than 90, which does not satisfy the demand of color-critical upmarket applications, such as photography, cinematography, and art galleries. In this work, two semiconductive chloroplumbate (chloride anion of lead(ii)) hybrids, obtained using a new inorganic–organic hybrid strategy, show unprecedented 3-D inorganic framework structures and white-light-emitting properties with high CRI values around 90, one of which shows the highest value to date. PMID:28757985
Savory, Christopher N; Ganose, Alex M; Travis, Will; Atri, Ria S; Palgrave, Robert G; Scanlon, David O
2016-08-28
As the worldwide demand for energy increases, low-cost solar cells are being looked to as a solution for the future. To attain this, non-toxic earth-abundant materials are crucial, however cell efficiencies for current materials are limited in many cases. In this article, we examine the two silver copper sulfides AgCuS and Ag 3 CuS 2 as possible solar absorbers using hybrid density functional theory, diffuse reflectance spectroscopy, XPS and Hall effect measurements. We show that both compounds demonstrate promising electronic structures and band gaps for high theoretical efficiency solar cells, based on Shockley-Queisser limits. Detailed analysis of their optical properties, however, indicates that only AgCuS should be of interest for PV applications, with a high theoretical efficiency. From this, we also calculate the band alignment of AgCuS against various buffer layers to aid in future device construction.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhao, Huijuan; Yun, Di; Hoelzer, David
In order to extend the operating license of current light water reactors (LWRs) in the United States and other countries to as many as 80 years or longer, it is demanding to identify potential materials for many of the internal structural components and fasteners. We proposed that 14YWT iron alloy can be adopted in such applications with its excellent material properties, such as high-temperature strength, low creep rate, and high irradiation resistance. Application with 14YWT would improve the void/helium swelling characteristics of the LWR fuels, extend the burn-up limits with the tolerant temperature up to 800oC and reduce the hydrogenmore » production. One key feature of 14YWT material property enhancement is the ultrafine high density of 2-4nm Y-Ti-O enriched nanoclusters (NCs) within the 14YWT iron matrix. The NCs can effectively pin the ultra-fine grain boundaries and dislocations, which significantly enhance mechanical properties of the alloy. Moreover, these nanoclusters remain stable with no coarsening after a large dose of ion irradiation. After ion irradiation, the helium bubbles are observed extremely uniform in size (1nm) and quite homogeneously distributed within the 14YWT matrix, which indicates that the microstructure of 14YWT remains remarkably tolerance to radiation damage. However, there is a lack of understanding of 14YWT both theoretically and experimentally in order to understand the mechanism behind the material property enhancement and to further develop and design a new generation of advanced structural material for current LWR applications and future fusion applications.« less
Physical demand of seven closed agility drills.
Atkinson, Mark; Rosalie, Simon; Netto, Kevin
2016-11-01
The present study aimed to quantify the demand of seven generic, closed agility drills. Twenty males with experience in invasion sports volunteered to participate in this study. They performed seven, closed agility drills over a standardised 30-m distance. Physical demand measures of peak velocity, total foot contacts, peak impacts, completion time, and maximum heart rate were obtained via the use of wearable sensor technologies. A subjective rating of perceived exertion (RPE) was also obtained. All measures, with the exception of maximum heart rates and RPE were able to delineate drills in terms of physical and physiological demand. The findings of this study exemplify the differences in demand of agility-type movements. Drill demand was dictated by the type of agility movement initiated with the increase in repetitiveness of a given movement type also contributing to increased demand. Findings from this study suggest agility drills can be manipulated to vary physical and physiological demand. This allows for the optimal application of training principles such as overload, progression, and periodisation.
Quantitative Aspects of Single Molecule Microscopy
Ober, Raimund J.; Tahmasbi, Amir; Ram, Sripad; Lin, Zhiping; Ward, E. Sally
2015-01-01
Single molecule microscopy is a relatively new optical microscopy technique that allows the detection of individual molecules such as proteins in a cellular context. This technique has generated significant interest among biologists, biophysicists and biochemists, as it holds the promise to provide novel insights into subcellular processes and structures that otherwise cannot be gained through traditional experimental approaches. Single molecule experiments place stringent demands on experimental and algorithmic tools due to the low signal levels and the presence of significant extraneous noise sources. Consequently, this has necessitated the use of advanced statistical signal and image processing techniques for the design and analysis of single molecule experiments. In this tutorial paper, we provide an overview of single molecule microscopy from early works to current applications and challenges. Specific emphasis will be on the quantitative aspects of this imaging modality, in particular single molecule localization and resolvability, which will be discussed from an information theoretic perspective. We review the stochastic framework for image formation, different types of estimation techniques and expressions for the Fisher information matrix. We also discuss several open problems in the field that demand highly non-trivial signal processing algorithms. PMID:26167102
3D laser scanning and modelling of the Dhow heritage for the Qatar National Museum
NASA Astrophysics Data System (ADS)
Wetherelt, A.; Cooper, J. P.; Zazzaro, C.
2014-08-01
Curating boats can be difficult. They are complex structures, often demanding to conserve whether in or out of the water; they are usually large, difficult to move on land, and demanding of gallery space. Communicating life on board to a visiting public in the terra firma context of a museum can be difficult. Boats in their native environment are inherently dynamic artifacts. In a museum they can be static and divorced from the maritime context that might inspire engagement. New technologies offer new approaches to these problems. 3D laser scanning and digital modeling offers museums a multifaceted means of recording, monitoring, studying and communicating watercraft in their care. In this paper we describe the application of 3D laser scanning and subsequent digital modeling. Laser scans were further developed using computer-generated imagery (CGI) modeling techniques to produce photorealistic 3D digital models for development into interactive, media-based museum displays. The scans were also used to generate 2D naval lines and orthographic drawings as a lasting curatorial record of the dhows held by the National Museum of Qatar.
Deep-Learning-Enabled On-Demand Design of Chiral Metamaterials.
Ma, Wei; Cheng, Feng; Liu, Yongmin
2018-06-11
Deep-learning framework has significantly impelled the development of modern machine learning technology by continuously pushing the limit of traditional recognition and processing of images, speech, and videos. In the meantime, it starts to penetrate other disciplines, such as biology, genetics, materials science, and physics. Here, we report a deep-learning-based model, comprising two bidirectional neural networks assembled by a partial stacking strategy, to automatically design and optimize three-dimensional chiral metamaterials with strong chiroptical responses at predesignated wavelengths. The model can help to discover the intricate, nonintuitive relationship between a metamaterial structure and its optical responses from a number of training examples, which circumvents the time-consuming, case-by-case numerical simulations in conventional metamaterial designs. This approach not only realizes the forward prediction of optical performance much more accurately and efficiently but also enables one to inversely retrieve designs from given requirements. Our results demonstrate that such a data-driven model can be applied as a very powerful tool in studying complicated light-matter interactions and accelerating the on-demand design of nanophotonic devices, systems, and architectures for real world applications.
NASA Astrophysics Data System (ADS)
Gaspar Aparicio, R.; Gomez, D.; Coterillo Coz, I.; Wojcik, D.
2012-12-01
At CERN a number of key database applications are running on user-managed MySQL database services. The database on demand project was born out of an idea to provide the CERN user community with an environment to develop and run database services outside of the actual centralised Oracle based database services. The Database on Demand (DBoD) empowers the user to perform certain actions that had been traditionally done by database administrators, DBA's, providing an enterprise platform for database applications. It also allows the CERN user community to run different database engines, e.g. presently open community version of MySQL and single instance Oracle database server. This article describes a technology approach to face this challenge, a service level agreement, the SLA that the project provides, and an evolution of possible scenarios.
Leadership Skills and Challenges in Hospitality Management Education
ERIC Educational Resources Information Center
Kalargyrou, Valentini
2009-01-01
Leaders in hospitality management education face diverse challenges in today's competitive and changing environment. Evolving demands from superiors, financial challenges, and faculty and students increasing demands, create a turbulent environment in which administrators must thrive. One of the keys in being effective leaders is the application of…
Pc-Based Floating Point Imaging Workstation
NASA Astrophysics Data System (ADS)
Guzak, Chris J.; Pier, Richard M.; Chinn, Patty; Kim, Yongmin
1989-07-01
The medical, military, scientific and industrial communities have come to rely on imaging and computer graphics for solutions to many types of problems. Systems based on imaging technology are used to acquire and process images, and analyze and extract data from images that would otherwise be of little use. Images can be transformed and enhanced to reveal detail and meaning that would go undetected without imaging techniques. The success of imaging has increased the demand for faster and less expensive imaging systems and as these systems become available, more and more applications are discovered and more demands are made. From the designer's perspective the challenge to meet these demands forces him to attack the problem of imaging from a different perspective. The computing demands of imaging algorithms must be balanced against the desire for affordability and flexibility. Systems must be flexible and easy to use, ready for current applications but at the same time anticipating new, unthought of uses. Here at the University of Washington Image Processing Systems Lab (IPSL) we are focusing our attention on imaging and graphics systems that implement imaging algorithms for use in an interactive environment. We have developed a PC-based imaging workstation with the goal to provide powerful and flexible, floating point processing capabilities, along with graphics functions in an affordable package suitable for diverse environments and many applications.
Advanced nondestructive techniques applied for the detection of discontinuities in aluminum foams
NASA Astrophysics Data System (ADS)
Katchadjian, Pablo; García, Alejandro; Brizuela, Jose; Camacho, Jorge; Chiné, Bruno; Mussi, Valerio; Britto, Ivan
2018-04-01
Metal foams are finding an increasing range of applications by their lightweight structure and physical, chemical and mechanical properties. Foams can be used to fill closed moulds for manufacturing structural foam parts of complex shape [1]; foam filled structures are expected to provide good mechanical properties and energy absorption capabilities. The complexity of the foaming process and the number of parameters to simultaneously control, demand a preliminary and hugely wide experimental activity to manufacture foamed components with a good quality. That is why there are many efforts to improve the structure of foams, in order to obtain a product with good properties. The problem is that even for seemingly identical foaming conditions, the effective foaming can vary significantly from one foaming trial to another. The variation of the foams often is related by structural imperfections, joining region (foam-foam or foam-wall mold) or difficulties in achieving a complete filling of the mould. That is, in a closed mold, the result of the mold filling and its structure or defects are not known a priori and can eventually vary significantly. These defects can cause a drastic deterioration of the mechanical properties [2] and lead to a low performance in its application. This work proposes the use of advanced nondestructive techniques for evaluating the foam distribution after filling the mold to improve the manufacturing process. To achieved this purpose ultrasonic technique (UT) and cone beam computed tomography (CT) were applied on plate and structures of different thicknesses filled with foam of different porosity. UT was carried out on transmission mode with low frequency air-coupled transducers [3], in focused and unfocused configurations.
Task Assignment Heuristics for Distributed CFD Applications
NASA Technical Reports Server (NTRS)
Lopez-Benitez, N.; Djomehri, M. J.; Biswas, R.; Biegel, Bryan (Technical Monitor)
2001-01-01
CFD applications require high-performance computational platforms: 1. Complex physics and domain configuration demand strongly coupled solutions; 2. Applications are CPU and memory intensive; and 3. Huge resource requirements can only be satisfied by teraflop-scale machines or distributed computing.
Prabhakar, Janani; Hudson, Judith A
2014-11-01
Previous studies suggest that the ability to think about and act on the future emerges between 3 and 5 years of age. However, it is unclear what underlying processes change during the development of early future-oriented behavior. We report three experiments that tested the emergence of future thinking ability through children's ability to explicitly maintain future goals and construct future scenarios. Our main objectives were to examine the effects of goal structure and the effects of working memory demands on children's ability to construct future scenarios and make choices to satisfy future goals. The results indicate that 4-year-olds were able to successfully accomplish two temporally ordered goals even with high working memory demands and a complex goal structure, whereas 3-year-olds were able to accomplish two goals only when the working memory demands were low and the goal structure did not involve additional demands from inferential reasoning and contingencies between the temporally ordered goals. Results are discussed in terms of the development of future thinking in conjunction with working memory, inferential reasoning ability, and goal maintenance abilities. Copyright © 2014. Published by Elsevier Inc.
University Transformation: New Demands and Coping Strategies
ERIC Educational Resources Information Center
Chidindi, Joseph
2012-01-01
University education system is undergoing transformation requirements particularly in the developing world. The demands require adaptation to the prevailing circumstances hence the need for relevant strategies for universities. Issues such as institutional profiles, organizational structure and work integration, research activities, and funding…
Platinum replica electron microscopy: Imaging the cytoskeleton globally and locally.
Svitkina, Tatyana M
2017-05-01
Structural studies reveal how smaller components of a system work together as a whole. However, combining high resolution of details with full coverage of the whole is challenging. In cell biology, light microscopy can image many cells in their entirety, but at a lower resolution, whereas electron microscopy affords very high resolution, but usually at the expense of the sample size and coverage. Structural analyses of the cytoskeleton are especially demanding, because cytoskeletal networks are unresolvable by light microscopy due to their density and intricacy, whereas their proper preservation is a challenge for electron microscopy. Platinum replica electron microscopy can uniquely bridge the gap between the "comfort zones" of light and electron microscopy by allowing high resolution imaging of the cytoskeleton throughout the entire cell and in many cells in the population. This review describes the principles and applications of platinum replica electron microscopy for studies of the cytoskeleton. Copyright © 2017 Elsevier Ltd. All rights reserved.
Insights on synergy of materials and structures in biomimetic platelet-matrix composites
NASA Astrophysics Data System (ADS)
Sakhavand, Navid; Shahsavari, Rouzbeh
2018-01-01
Hybrid materials such as biomimetic platelet-matrix composites are in high demand to confer low weight and multifunctional mechanical properties. This letter reports interfacial-bond regulated assembly of polymers on cement-an archetype model with significant infrastructure applications. We demonstrate a series of 20+ molecular dynamics studies on decoding and optimizing the complex interfacial interactions including the role and types of various heterogeneous, competing interfacial bonds that are key to adhesion and interfacial strength. Our results show an existence of an optimum overlap length scale (˜15 nm) between polymers and cement crystals, exhibiting the best balance of strength, toughness, stiffness, and ductility for the composite. This finding, combined with the fundamental insights into the nature of interfacial bonds, provides key hypotheses for selection and processing of constituents to deliberate the best synergy in the structure and materials of platelet-matrix composites.
Platinum Replica Electron Microscopy: Imaging the Cytoskeleton Globally and Locally
SVITKINA, Tatyana M.
2017-01-01
Structural studies reveal how smaller components of a system work together as a whole. However, combining high resolution of details with full coverage of the whole is challenging. In cell biology, light microscopy can image many cells in their entirety, but at a lower resolution, whereas electron microscopy affords very high resolution, but usually at the expense of the sample size and coverage. Structural analyses of the cytoskeleton are especially demanding, because cytoskeletal networks are unresolvable by light microscopy due to their density and intricacy, whereas their proper preservation is a challenge for electron microscopy. Platinum replica electron microscopy can uniquely bridge the gap between the “comfort zones” of light and electron microscopy by allowing high resolution imaging of the cytoskeleton throughout the entire cell and in many cells in the population. This review describes the principles and applications of platinum replica electron microscopy for studies of the cytoskeleton. PMID:28323208
Structured thermal surface for radiative camouflage.
Li, Ying; Bai, Xue; Yang, Tianzhi; Luo, Hailu; Qiu, Cheng-Wei
2018-01-18
Thermal camouflage has been successful in the conductive regime, where thermal metamaterials embedded in a conductive system can manipulate heat conduction inside the bulk. Most reported approaches are background-dependent and not applicable to radiative heat emitted from the surface of the system. A coating with engineered emissivity is one option for radiative camouflage, but only when the background has uniform temperature. Here, we propose a strategy for radiative camouflage of external objects on a given background using a structured thermal surface. The device is non-invasive and restores arbitrary background temperature distributions on its top. For many practical candidates of the background material with similar emissivity as the device, the object can thereby be radiatively concealed without a priori knowledge of the host conductivity and temperature. We expect this strategy to meet the demands of anti-detection and thermal radiation manipulation in complex unknown environments and to inspire developments in phononic and photonic thermotronics.
Further optimization of SeDDaRA blind image deconvolution algorithm and its DSP implementation
NASA Astrophysics Data System (ADS)
Wen, Bo; Zhang, Qiheng; Zhang, Jianlin
2011-11-01
Efficient algorithm for blind image deconvolution and its high-speed implementation is of great value in practice. Further optimization of SeDDaRA is developed, from algorithm structure to numerical calculation methods. The main optimization covers that, the structure's modularization for good implementation feasibility, reducing the data computation and dependency of 2D-FFT/IFFT, and acceleration of power operation by segmented look-up table. Then the Fast SeDDaRA is proposed and specialized for low complexity. As the final implementation, a hardware system of image restoration is conducted by using the multi-DSP parallel processing. Experimental results show that, the processing time and memory demand of Fast SeDDaRA decreases 50% at least; the data throughput of image restoration system is over 7.8Msps. The optimization is proved efficient and feasible, and the Fast SeDDaRA is able to support the real-time application.
EBF3 Design and Sustainability Considerations
NASA Technical Reports Server (NTRS)
Taminger, Karen M. B.
2015-01-01
Electron beam freeform fabrication (EBF3) is a cross-cutting technology for producing structural metal parts using an electron beam and wire feed in a layer-additive fashion. This process was developed by researchers at NASA Langley to specifically address needs for aerospace applications. Additive manufacturing technologies like EBF3 enable efficient design of materials and structures by tailoring microstructures and chemistries at the local level to improve performance at the global level. Additive manufacturing also facilitates design freedom by integrating assemblies into complex single-piece components, eliminating flanges, fasteners and joints, resulting in reduced size and mass. These same efficiencies that permit new design paradigms also lend themselves to supportability and sustainability. Long duration space missions will require a high degree of self-sustainability. EBF3 is a candidate technology being developed to allow astronauts to conduct repairs and fabricate new components and tools on demand, with efficient use of feedstock materials and energy.
Thermally driven anomalous Hall effect transitions in FeRh
NASA Astrophysics Data System (ADS)
Popescu, Adrian; Rodriguez-Lopez, Pablo; Haney, Paul M.; Woods, Lilia M.
2018-04-01
Materials exhibiting controllable magnetic phase transitions are currently in demand for many spintronics applications. Here, we investigate from first principles the electronic structure and intrinsic anomalous Hall, spin Hall, and anomalous Nernst response properties of the FeRh metallic alloy which undergoes a thermally driven antiferromagnetic-to-ferromagnetic phase transition. We show that the energy band structures and underlying Berry curvatures have important signatures in the various Hall effects. Specifically, the suppression of the anomalous Hall and Nernst effects in the antiferromagnetic state and a sign change in the spin Hall conductivity across the transition are found. It is suggested that the FeRh can be used as a spin current detector capable of differentiating the spin Hall effect from other anomalous transverse effects. The implications of this material and its thermally driven phases as a spin current detection scheme are also discussed.
[Cigarette taxes and demand in Colombia].
Maldonado, Norman; Llorente, Blanca; Deaza, Javier
2016-10-01
Estimate price and income elasticities of aggregate demand for cigarettes in Colombia, by controlling for structural market changes since the late 1990s, to identify policy opportunities for taxes that could improve public health and increase tax revenues. Measurement of aggregate demand for cigarettes using gross income reported on value-added tax returns submitted to Colombia's National Tax and Customs Office (DIAN is the acronym in Spanish) by the tobacco product manufacturing industry, subtracting exports. A quarterly time series was obtained for the period 1994-2014. The econometric estimation using two-stage least squares controls for price endogeneity and uses a set of dummy variables to control for structural changes in the market and in its regulation. Demand is, from a statistical standpoint, sensitive to price and to income. Price elasticity of demand is -0.78 and income elasticity is 0.61. Inelastic demand implies that it is possible, through cigarette excise taxes, to meet public health targets and increase revenues simultaneously. The results also suggest that the considerable increase in household income in Colombia in the first decade of the 21st century increased purchasing power, which, lacking an accompanying tax increase, promoted cigarette consumption, with negative effects on public health, and wasted an opportunity to increase tax revenues.
Näswall, Katharina; Burt, Christopher D B; Pearce, Megan
2015-01-01
This study investigated the impact of workload demands on perceived job risk using the Job Demand-Control model as a research framework. The primary objective was to test the hypothesis that employee control over work scheduling and overtime would moderate the relationship between workload demands and perceived job risk. Ninety-six participants working in a variety of industries completed measures of workload demands, and of control over work scheduling and overtime, and a measure of perceived job risk. Workload demands predicted higher perceptions of job risk. However, the results also suggest that control over overtime moderated this relationship, where those with the combination of high workload demands and low control over overtime reported higher levels of perceived risk. The results indicate that the JDC model is applicable to safety research. The results suggest that employee control over workload demands is an important variable to consider in terms of managing workplace safety. The present study also points to important areas for future research to explore in order to further understand the connection between demands and safety.
Performance of nickel-based oxygen carrier produced using renewable fuel aloe vera
NASA Astrophysics Data System (ADS)
Afandi, NF; Devaraj, D.; Manap, A.; Ibrahim, N.
2017-04-01
Consuming and burning of fuel mainly fossil fuel has gradually increased in this upcoming era due to high-energy demand and causes the global warming. One of the most effective ways to reduce the greenhouse gases is by capturing carbon dioxide (CO2) during the combustion process. Chemical looping combustion (CLC) is one of the most effective methods to capture the CO2 without the need of an energy intensive air separation unit. This method uses oxygen carrier to provide O2 that can react with fuel to form CO2 and H2O. This research focuses on synthesizing NiO/NiAl2O4 as an oxygen carrier due to its properties that can withstand high temperature during CLC application. The NiO/NiAl2O4 powder was synthesized using solution combustion method with plant extract renewable fuel, aloe vera as the fuel. In order to optimize the performance of the particles that can be used in CLC application, various calcination temperatures were varied at 600°C, 800°C, 1050°C and 1300°C. The phase and morphology of obtained powders were characterized using X-ray diffraction (XRD) and Field Emission Microscopy (FESEM) respectively together with the powder elements. In CLC application, high reactivity can be achieved by using smaller particle size of oxygen carrier. This research succeeded in producing nano-structured powder with high crystalline structure at temperature 1050°C which is suitable to be used in CLC application.
NASA Astrophysics Data System (ADS)
Lee, Keun
Renewable energy in different forms has been used in various applications for survival since the beginning of human existence. However, there is a new dire need to reevaluate and recalibrate the overall energy issue both nationally and globally. This includes, but is not limited to, the finite availability of fossil fuel, energy sustainability with an increasing demand, escalating energy costs, environmental impact such as global warming and green-house gases, to name a few. This dissertation is primarily focused and related to the production and usage of electricity from non-hydro renewable sources. Among non-hydro renewable energy sources, electricity generation from wind and solar energy are the fastest-growing technologies in the United States and in the world. However, due to the intermittent nature of such renewable sources, energy storage devices are required to maintain proper operation of the grid system and in order to increase reliability. A hybrid system, as the name suggests, is a combination of different forms of non-renewable and renewable energy generation, with or without storage devices. Hybrid systems, when applied properly, are able to improve reliability and enhance stability, reduce emissions and noise pollution, provide continuous power, increase operation life, reduce cost, and efficiently use all available energy. In the United States (U.S.), buildings consume approximately 40% of the total primary energy and 74% of the total electricity. Therefore, reduction of energy consumption and improved energy efficiency in U.S. buildings will play a vital role in the overall energy picture. Electrical energy usage for any such building varies widely depending on age (construction technique), electricity and natural gas usage, appearance, location and climate. In this research, a hybrid system including non-renewable and renewable energy generation with storage devices specifically for building applications, is studied in detail. This research deals with the optimization of the hybrid system design (which consists of PV panels and/or wind turbines and/or storage devices for building applications) by developing an algorithm designed to make the system cost effective and energy efficient. Input data includes electrical load demand profile of the buildings, buildings' structural and geographical characteristics, real time pricing of electricity, and the costs of hybrid systems and storage devices. When the electrical load demand profile of a building that is being studied is available, a measured demand profile is directly used as input data. However, if that information is not available, a building's electric load demand is estimated using a developed algorithm based on three large data sources from a public domain, and used as input data. Using the acquired input data, the algorithm of this research is designed and programmed in order to determine the size of renewable components and to minimize the total yearly net cost. This dissertation also addresses the parametric sensitivity analysis to determine which factors are more significant and are expected to produce useful guidelines in the decision making process. An engineered and more practical, simplified solution has been provided for the optimized design process.
FOSSIL2 energy policy model documentation: generic structures of the FOSSIL2 model
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
1980-10-01
This report discusses the structure, derivations, assumptions, and mathematical formulation of the FOSSIL2 model. Each major facet of the model - supply/demand interactions, industry financing, and production - has been designed to parallel closely the actual cause/effect relationships determining the behavior of the United States energy system. The data base for the FOSSIL2 program is large. When possible, all data were obtained from sources well known to experts in the energy field. Cost and resource estimates are based on DOE data whenever possible. This report presents the FOSSIL2 model at several levels. In Volume I, an overview of the basicmore » structures, assumptions, and behavior of the FOSSIL2 model is presented so that the reader can understand the results of various policy tests. The discussion covers the three major building blocks, or generic structures, used to construct the model: supply/demand balance; finance and capital formation; and energy production. These structures reflect the components and interactions of the major processes within each energy industry that directly affect the dynamics of fuel supply, demand, and price within the energy system as a whole.« less
Hierarchically structured materials for lithium batteries
NASA Astrophysics Data System (ADS)
Xiao, Jie; Zheng, Jianming; Li, Xiaolin; Shao, Yuyan; Zhang, Ji-Guang
2013-10-01
The lithium-ion battery (LIB) is one of the most promising power sources to be deployed in electric vehicles, including solely battery powered vehicles, plug-in hybrid electric vehicles, and hybrid electric vehicles. With the increasing demand for devices of high-energy densities (>500 Wh kg-1), new energy storage systems, such as lithium-oxygen (Li-O2) batteries and other emerging systems beyond the conventional LIB, have attracted worldwide interest for both transportation and grid energy storage applications in recent years. It is well known that the electrochemical performance of these energy storage systems depends not only on the composition of the materials, but also on the structure of the electrode materials used in the batteries. Although the desired performance characteristics of batteries often have conflicting requirements with the micro/nano-structure of electrodes, hierarchically designed electrodes can be tailored to satisfy these conflicting requirements. This work will review hierarchically structured materials that have been successfully used in LIB and Li-O2 batteries. Our goal is to elucidate (1) how to realize the full potential of energy materials through the manipulation of morphologies, and (2) how the hierarchical structure benefits the charge transport, promotes the interfacial properties and prolongs the electrode stability and battery lifetime.
Environmental variables can be important factors in recreation demand. Analysts wishing to quantify environmental quality impacts face the difficult issue of isolating them from unobserved variables. Quality changes may occur in space, varying between sites, or in time, varying b...
Two Propositions on the Application of Point Elasticities to Finite Price Changes.
ERIC Educational Resources Information Center
Daskin, Alan J.
1992-01-01
Considers counterintuitive propositions about using point elasticities to estimate quantity changes in response to price changes. Suggests that elasticity increases with price along a linear demand curve, but falling quantity demand offsets it. Argues that point elasticity with finite percentage change in price only approximates percentage change…
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-30
... to Demands in Legal Proceedings Among Private Litigants AGENCY: Office of the General Counsel, HUD... forms of information technology, e.g., permitting electronic submission of responses. This Notice also... Response to Demands in Legal Proceedings Among Private Litigants. OMB Control Number, if applicable: 2501...
Software on Demand: An Early Childhood Numeracy Partnership
ERIC Educational Resources Information Center
Egan, Mike; Hengst, Randy
2012-01-01
In collaboration with preservice elementary teachers and in-service kindergarten teachers, the authors engaged in small-scale, demand-side production of educational software focused on numeracy skills. That is, the authors built applications designed to address children's specific learning needs as they surfaced in the classroom and were…
Minimum stiffness criteria for ring frame stiffeners of space launch vehicles
NASA Astrophysics Data System (ADS)
Friedrich, Linus; Schröder, Kai-Uwe
2016-12-01
Frame stringer-stiffened shell structures show high load carrying capacity in conjunction with low structural mass and are for this reason frequently used as primary structures of aerospace applications. Due to the great number of design variables, deriving suitable stiffening configurations is a demanding task and needs to be realized using efficient analysis methods. The structural design of ring frame stringer-stiffened shells can be subdivided into two steps. One, the design of a shell section between two ring frames. Two, the structural design of the ring frames such that a general instability mode is avoided. For sizing stringer-stiffened shell sections, several methods were recently developed, but existing ring frame sizing methods are mainly based on empirical relations or on smeared models. These methods do not mandatorily lead to reliable designs and in some cases the lightweight design potential of stiffened shell structures can thus not be exploited. In this paper, the explicit physical behaviour of ring frame stiffeners of space launch vehicles at the onset of panel instability is described using mechanical substitute models. Ring frame stiffeners of a stiffened shell structure are sized applying existing methods and the method suggested in this paper. To verify the suggested method and to demonstrate its potential, geometrically non-linear finite element analyses are performed using detailed finite element models.