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NUMIT has been refined, developed, and greatly enhanced so that it can be used to model and predict the deep charging of dielectrics on spacecraft. The new tool, called AF-NUMIT2, can now model isotropically incident electron fluxes from realistic energy spectra that change with time. The model has been extended to incident electron fluxes an order of magnitude lower than before (less than = 10 keV), and aspects of the model have been checked against Monte Carlo simulations. Electron energy flux spectra, as measured by CRRES, have been used in dozens of simulations of Kapton charging over multiple days. Kapton has been modeled with both dark conductivities and radiation induced conductivities extending over two orders-of-magnitude. The result is a surprisingly consistent relationship between maximum internal electric field strengths and conductivity, regardless of the particular incident electron spectra.

Estuaries, fjords and sounds are important, major components of marine ecosystems worldwide. Because of this, and their generally poor treatment by man, large estuaries should be the focus of large-scale, multidisciplinary, integrative modeling efforts. We need to both understand how these systems work, and be able to predict how they will respond to changes, whether natural or anthropogenic. Puget Sound, Washington State's largest inland sea, is both the largest fjord in the lower forty-eight states and closest to the substantial urban centers of Seattle, Tacoma, Everett and surrounding communities. Relative to other coastal systems, Pacific Northwest fjords have seasonally high annual phytoplankton standing stock and primary production, and they support several economically valuable fisheries. Our long-term goals are to develop quantitative understanding of the seasonal and longer time-scale variabilities of the Sound s circulation, roles of water column stratification, nutrients, and light (and their interactions) on phytoplankton and zooplankton dynamics, and the sensitivity of the physical and the biological system to natural and human perturbations. We will develop models of Puget Sound that can aid agencies with responsibilities for environmental management in making informed decisions and serve as marine science education tools.

The goal of the Battlespace Environments Institute (BEI) is to integrate Earth and space modeling capabilities into a seamless, whole-Earth common modeling infrastructure that facilitates interservice development of multiple, mission-specific environmental simulations and supports battlefield decisions, improves interoperability, and reduces operating costs.

Puget Sound, Washington, is both the largest fjord in the lower forty-eight states and closest to the substantial urban centers of Seattle, Tacoma, Everett and surrounding communities. The sound has seasonally high annual phytoplankton standing stock and primary production, and they support several economically valuable fisheries. Our long-term goals are to develop quantitative understanding of the Sound's circulation and marine ecosystem, and of the sensitivity of the physical and the biological system to natural and human perturbations; and to develop models of Puget Sound that can aid agencies with responsibilities for environmental management in making informed decisions and serve as marine science education tools.

A preliminary statistical analysis of the ATS-5 and ATS-6 geosynchronous plasma data has been carried out. Variations in the electron and ion currents and temperatures, as represented by the single Maxwellian component temperatures T(AVG) and T(RMS), are evaluated with respect to local time and geomagnetic activity. The potential on the satellites is similarly evaluated. Results indicate that the geosynchronous plasma cannot be adequately represented by a simple Maxwellian distribution and that, at the very least, a two component Maxwellian is necessary. The electron current and eclipse potential were found to vary strongly with K sub p while the temperatures only varied weakly. Local time variations in temperature and current were observed but these were outweighed by a significant local time variation in satellite potential which peaked near midnight. An explanation of these results is proposed in terms of a simple model of the time evolution of the plasma following an injection.

A preliminary statistical analysis of the ATS-5 and ATS-6 geosynchronous plasma data has been carried out. Variations in the electron and ion currents and temperatures, as represented by the single Maxwellian component temperatures T(AVG) and T(RMS), are evaluated with respect to local time and geomagnetic activity. The potential on the satellites is similarly evaluated. Results indicate that the geosynchronous plasma cannot be adequately represented by a simple Maxwellian distribution and that, at the very least, a two component Maxwellian is necessary. The electron current and eclipse potential were found to vary strongly with K sub p while the temperatures only varied weakly. Local time variations in temperature and current were observed but these were outweighed by a significant local time variation in satellite potential which peaked near midnight. An explanation of these results is proposed in terms of a simple model of the time evolution of the plasma following an injection.

A preliminary statistical analysis of the ATS-5 and ATS-6 geosynchronous plasma data has been carried out. Variations in the electron and ion currents and temperatures, as represented by the single Maxwellian component temperatures T(AVG) and T(RMS), are evaluated with respect to local time and geomagnetic activity. The potential on the satellites is similarly evaluated. Results indicate that the geosynchronous plasma cannot be adequately represented by a simple Maxwellian distribution and that, at the very least, a two component Maxwellian is necessary. The electron current and eclipse potential were found to vary strongly with K sub p while the temperatures only varied weakly. Local time variations in temperature and current were observed but these were outweighed by a significant local time variation in satellite potential which peaked near midnight. An explanation of these results is proposed in terms of a simple model of the time evolution of the plasma following an injection.

A preliminary statistical analysis of the ATS-5 and ATS-6 geosynchronous plasma data has been carried out. Variations in the electron and ion currents and temperatures, as represented by the single Maxwellian component temperatures T(AVG) and T(RMS), are evaluated with respect to local time and geomagnetic activity. The potential on the satellites is similarly evaluated. Results indicate that the geosynchronous plasma cannot be adequately represented by a simple Maxwellian distribution and that, at the very least, a two component Maxwellian is necessary. The electron current and eclipse potential were found to vary strongly with K sub p while the temperatures only varied weakly. Local time variations in temperature and current were observed but these were outweighed by a significant local time variation in satellite potential which peaked near midnight. An explanation of these results is proposed in terms of a simple model of the time evolution of the plasma following an injection.

The MESSAGE Integrated Assessment Model (IAM) developed by IIASA has been a central tool of energy-environment-economy systems analysis in the global scientific and policy arena. It played a major role in the Assessment Reports of the Intergovernmental Panel on Climate Change (IPCC); it provided marker scenarios of the Representative Concentration Pathways (RCPs) and the Shared Socio-Economic Pathways (SSPs); and it underpinned the analysis of the Global Energy Assessment (GEA). Alas, to provide relevant analysis for current and future challenges, numerical models of human and earth systems need to support higher spatial and temporal resolution, facilitate integration of data sources and methodologies across disciplines, and become open and transparent regarding the underlying data, methods, and the scientific workflow. In this manuscript, we present the building blocks of a new framework for an integrated assessment modeling platform; the “ecosystem” comprises: i) an open-source GAMS implementation of the MESSAGE energy++ system model integrated with the MACRO economic model; ii) a Java/database back-end for version-controlled data management, iii) interfaces for the scientific programming languages Python & R for efficient input data and results processing workflows; and iv) a web-browser-based user interface for model/scenario management and intuitive “drag-and-drop” visualization of results. The framework aims to facilitate the highest level of openness for scientific analysis, bridging the need for transparency with efficient data processing and powerful numerical solvers. The platform is geared towards easy integration of data sources and models across disciplines, spatial scales and temporal disaggregation levels. All tools apply best-practice in collaborative software development, and comprehensive documentation of all building blocks and scripts is generated directly from the GAMS equations and the Java/Python/R source code.

The MESSAGE Integrated Assessment Model (IAM) developed by IIASA has been a central tool of energy-environment-economy systems analysis in the global scientific and policy arena. It played a major role in the Assessment Reports of the Intergovernmental Panel on Climate Change (IPCC); it provided marker scenarios of the Representative Concentration Pathways (RCPs) and the Shared Socio-Economic Pathways (SSPs); and it underpinned the analysis of the Global Energy Assessment (GEA). Alas, to provide relevant analysis for current and future challenges, numerical models of human and earth systems need to support higher spatial and temporal resolution, facilitate integration of data sources and methodologies across disciplines, and become open and transparent regarding the underlying data, methods, and the scientific workflow. In this manuscript, we present the building blocks of a new framework for an integrated assessment modeling platform; the “ecosystem” comprises: i) an open-source GAMS implementation of the MESSAGE energy++ system model integrated with the MACRO economic model; ii) a Java/database back-end for version-controlled data management, iii) interfaces for the scientific programming languages Python & R for efficient input data and results processing workflows; and iv) a web-browser-based user interface for model/scenario management and intuitive “drag-and-drop” visualization of results. The framework aims to facilitate the highest level of openness for scientific analysis, bridging the need for transparency with efficient data processing and powerful numerical solvers. The platform is geared towards easy integration of data sources and models across disciplines, spatial scales and temporal disaggregation levels. All tools apply best-practice in collaborative software development, and comprehensive documentation of all building blocks and scripts is generated directly from the GAMS equations and the Java/Python/R source code.

The goal of this project is to investigate the use of visualization software based on the visual programming and data-flow paradigms to meet the needs of the SPOF and through it the International Solar Terrestrial Physics (ISTP) science community. Specific needs we address include science planning, data interpretation, comparisons of data with simulation and model results, and data acquisition. Our accomplishments during the twelve month grant period are discussed below.

The goal of this project is to investigate the use of visualization software based on the visual programming and data-flow paradigms to meet the needs of the SPOF and through it the International Solar Terrestrial Physics (ISTP) science community. Specific needs we address include science planning, data interpretation, comparisons of data with simulation and model results, and data acquisition. Our accomplishments during the twelve month grant period are discussed below.

A 25 square kilometer urban area located in University Park, Texas was modeled using geographic information systems (GIS) software. A smaller 6.25 square kilometer area around the Southern Methodist University was extracted from the larger area and analyzed using an acoustic finite-difference time-domain (FDTD) code. The procedures to model the area using GIS software, extract required data, produce the data files necessary to perform the acoustic analyses, and view the results are described in this report. This report is focused on the details of using the particular software packages used in this study, but the concepts are general in nature and can be applied to other applications if needed.

The Blast Load Simulator (BLS) at the U.S. Army Engineer Research and Development Center (ERDC) has been utilized for applying simulated blast loads on structures for more than a decade; however, the experimental efforts to date have not included a computational modeling component. The Defense Threat Reduction Agency tasked ERDC to conduct an integrated experimental/computational program to evaluate several first principles codes (FPCs) for modeling airblast environments typical of those encountered in the BLS. The FPCs considered were CTH, DYSMAS, Loci/BLAST, RAGE, and SHAMRC. These codes afforded a range of numerical solvers and equation of state options for the modeling effort. The FPCs were evaluated against data generated in the BLS. Three experimental configurations were considered for the validation. These included two empty configurations, with comparisons drawn against reflected pressures measured at the downstream end wall. The third included a box-like structure in the flow field. The structure was instrumented on the exposed surfaces to provide a more challenging scenario for the model comparisons. The purpose of the integrated program was to assess computational accuracy and cost of the aforementioned FPCs and identify any shortcomings in the physics modeling and areas for future improvement. Findings from the integrated program are discussed in this report.

We present a detailed analysis of the 900 ks spectrum of NGC3783 obtained by Chandra in 2000-2001 (Kaspi et al. 2002). We split the data in various ways to look for time dependent and luminosity dependent spectral variations. This analysis, the measured equivalent widths of a large number of X-ray lines, and our photoionization calculations, lead us to the following conclusions: 1) NGC 3783 fluctuated in luminosity, by a factor N 1.5, during individual 170 ks observations. The fluctuations were not associated with significant spectral variations. 2) On a longer time scale, of 20-120 days, we discovered two very different spectral shapes that are noted the high state and the low state spectra. The observed changes between the two can be described as the appearance and disappearance of a soft continuum component. The spectral variations are not related, in a simple way, to the brightening or the fading of the short wavelength continuum, as observed in other objects. NGC3783 seems to be the first AGN to show this unusual behavior. 3) The appearance of the soft continuum component is consistent with beeing the only spectral variation and there is no need to invoke changes in the absorber s opacity. In particular, all absorption lines with reliable measurements show the same equivalent width, within the observational uncertainties, during high and low states. 4) Photoionization model calculations show that a combination of three ionization components, each split into two kinematic components, explain very well the intensity of almost all absorption lines and the bound-free absorption. The components span a large range of ionization and a total column of about 3 x 10(exp 22) per square centimeter Moreover, all components are thermally stable and are situated on the vertical branch of the stability curve.. This means that they are in pressure equilibrium and perhaps occupy the same volume of space. This is the first detection of such a multi-component equilibrium gas in AGN. 5) The only real discrepancy between the model and the observations is the wavelength of the iron M-shell UTA feature. This is most likely due to an underestimation of the dielectronic recombination O VI and discuss its possible origin. 6) The lower limit on the distance of the absorbing gas in NGC3783 is between 0.2 and 3.2 pc, depending of the specific ionization component. The constant pressure assumption imposes an upper limit of about 25 pc on the distance of the least ionized gas from the central sourec.

The motivation for using Flight Training Synthetic Environment Technology (FTSET) in military aviation is to create a cost-efficient and a risk-managed training environment. However, deciding on the appropriate mix of synthetic versus actual flight training remains a great unresolved issue. Further, FTSET usage and its adoption level may vary across the aviation community and flight training curricula. Turkish Army Aviation (TUAA) has employed FTSET in helicopter flight training since 1990. Since then, it has exhibited three different FTSET support usage patterns, which include an initial phase of lower support rates until 1997, a substantial increase phase from 1997-2001, and a leveling-off phase, where growth stagnated, from 2001-2006. The author hypothesized that this sequential phasing can be explained in terms of the organizational culture in which the FTSET is employed, organizational changes that favor FTSET usage and increasing FTSET expertise in the usage, and the current FTSET's limited technical capability and sole support for one type of helicopter. To test this hypothesis, the author developed a systems dynamics model of the FTSET adoption process that has three interrelated sectors: Technology Improvement and Acquisition, Technology Adoption, and Technology Discarding. The Diffusion Model also is used as a framework to help explain the TUAA's FTSET adoption process from 1990 to 2006. The purpose is to understand this adoption process and to generate a policy for the current and future FTSET adoption process.

Despite of the tireless work by space surveillance assets, much of the Earth debris environment is not easily measured or tracked. For every object that is in an orbit we can track, there are hundreds of small debris that are too small to be tracked but still large enough to damage spacecraft. In addition, even if we knew today's environment with perfect knowledge, the debris environment is dynamic and would change tomorrow. Therefore, orbital debris scientists rely on numerical modeling to understand the nature of the debris environment and its risk to space operations throughout Earth orbit and into the future. This talk will summarize the ways in which modeling complements measurements to help give us a better picture of what is occurring in Earth orbit, and helps us to better conduct current and future space operations.

No abstract available

This article is from PLoS ONE , volume 9 . Abstract Brain and vascular cells form a functionally integrated signalling network that is known as the neurovascular unit (NVU). The signalling (autocrine, paracrine and juxtacrine) between different elements of this unit, especially in humans, is difficult to disentangle in vivo. Developing representative in vitro models is therefore essential to better understand the cellular interactions that govern the neurovascular environment. We here describe a novel approach to assay these cellular interactions by combining a human adult cerebral microvascular endothelial cell line (hCMEC/D3) with a fetal ganglionic eminence-derived neural stem cell (hNSC) line. These cell lines provide abundant homogeneous populations of cells to produce a consistently reproducible in vitro model of endothelial morphogenesis and the ensuing NVU. Vasculature-like structures (VLS) interspersed with patches of differentiating neural cells only occurred when hNSCs were seeded onto a differentiated endothelium. These VLS emerged within 3 days of coculture and by day 6 were stabilizing. After 7 days of coculture, neuronal differentiation of hNSCs was increased 3-fold, but had no significant effect on astrocyte or oligodendrocyte differentiation. ZO1, a marker of adherens and tight junctions, was highly expressed in both undifferentiated and differentiated endothelial cells, but the adherens junction markers CD31 and VE-cadherin were significantly reduced in coculture by approximately 20%. A basement membrane, consisting of laminin, vitronectin, and collagen I and IV, separated the VLS from neural patches. This simple assay can assist in elucidating the cellular and molecular signaling involved in the formation of VLS, as well as the enhancement of neuronal differentiation through endothelial signaling.

Eating behaviors among a large population of children are studied as a dynamic process driven by nonlinear interactions in the sociocultural school environment. The impact of food association learning on diet dynamics, inspired by a pilot study conducted among Arizona children in Pre-Kindergarten to 8th grades, is used to build simple population-level learning models. Qualitatively, mathematical studies are used to highlight the possible ramifications of instruction, learning in nutrition, and health at the community level. Model results suggest that nutrition education programs at the population-level have minimal impact on improving eating behaviors, findings that agree with prior field studies. Hence, the incorporation of food association learning may be a better strategy for creating resilient communities of healthy and non-healthy eaters. A \textit{Ratatouille} effect can be observed when food association learners become food preference learners, a potential sustainable behavioral change, which in turn, may impact the overall distribution of healthy eaters. In short, this work evaluates the effectiveness of population-level intervention strategies and the importance of institutionalizing nutrition programs that factor in economical, social, cultural, and environmental elements that mesh well with the norms and values in the community.

The uncertainties in the predicted acoustic wavefield associated with the transmission of low-frequency sound from the continental slope, through the shelfbreak front, onto the continental shelf are examined. The locale and sensor geometry being investigated is that of the New England continental shelfbreak with a moored low-frequency sound source on the slope. Our method of investigation employs computational fluid mechanics coupled with computational acoustics. The coupled methodology for uncertainty estimation is that of Error Subspace Statistical Estimation. Specifically, based on observed oceanographic data during the 1996 Shelfbreak Primer Experiment, the Harvard University primitive-equation ocean model is initialized with many realizations of physical fields and then integrated to produce many realizations of a five-day regional forecast of the sound speed field. In doing so, the initial physical realizations are obtained by perturbing the physical initial conditions in statistical accord with a realistic error subspace. The different forecast realizations of the sound speed field are then fed into a Naval Postgraduate School coupled-mode sound propagation model to produce realizations of the predicted acoustic wavefield in a vertical plane across the shelfbreak frontal zone. The combined ocean and acoustic results from this Monte Carlo simulation study provide insights into the relations between the uncertainties in the ocean and acoustic estimates. The modeled uncertainties in the transmission loss estimate and their relations to the error statistics in the ocean estimate are discussed.

The uncertainties in the predicted acoustic wavefield associated with the transmission of low-frequency sound from the continental slope, through the shelfbreak front, onto the continental shelf are examined. The locale and sensor geometry being investigated is that of the New England continental shelfbreak with a moored low-frequency sound source on the slope. Our method of investigation employs computational fluid mechanics coupled with computational acoustics. The coupled methodology for uncertainty estimation is that of Error Subspace Statistical Estimation. Specifically, based on observed oceanographic data during the 1996 Shelfbreak Primer Experiment, the Harvard University primitive-equation ocean model is initialized with many realizations of physical fields and then integrated to produce many realizations of a five-day regional forecast of the sound speed field. In doing so, the initial physical realizations are obtained by perturbing the physical initial conditions in statistical accord with a realistic error subspace. The different forecast realizations of the sound speed field are then fed into a Naval Postgraduate School coupled-mode sound propagation model to produce realizations of the predicted acoustic wavefield in a vertical plane across the shelfbreak frontal zone. The combined ocean and acoustic results from this Monte Carlo simulation study provide insights into the relations between the uncertainties in the ocean and acoustic estimates. The modeled uncertainties in the transmission loss estimate and their relations to the error statistics in the ocean estimate are discussed.

The uncertainties in the predicted acoustic wavefield associated with the transmission of low-frequency sound from the continental slope, through the shelfbreak front, onto the continental shelf are examined. The locale and sensor geometry being investigated is that of the New England continental shelfbreak with a moored low-frequency sound source on the slope. Our method of investigation employs computational fluid mechanics coupled with computational acoustics. The coupled methodology for uncertainty estimation is that of Error Subspace Statistical Estimation. Specifically, based on observed oceanographic data during the 1996 Shelfbreak Primer Experiment, the Harvard University primitive-equation ocean model is initialized with many realizations of physical fields and then integrated to produce many realizations of a five-day regional forecast of the sound speed field. In doing so, the initial physical realizations are obtained by perturbing the physical initial conditions in statistical accord with a realistic error subspace. The different forecast realizations of the sound speed field are then fed into a Naval Postgraduate School coupled-mode sound propagation model to produce realizations of the predicted acoustic wavefield in a vertical plane across the shelfbreak frontal zone. The combined ocean and acoustic results from this Monte Carlo simulation study provide insights into the relations between the uncertainties in the ocean and acoustic estimates. The modeled uncertainties in the transmission loss estimate and their relations to the error statistics in the ocean estimate are discussed.

The uncertainties in the predicted acoustic wavefield associated with the transmission of low-frequency sound from the continental slope, through the shelfbreak front, onto the continental shelf are examined. The locale and sensor geometry being investigated is that of the New England continental shelfbreak with a moored low-frequency sound source on the slope. Our method of investigation employs computational fluid mechanics coupled with computational acoustics. The coupled methodology for uncertainty estimation is that of Error Subspace Statistical Estimation. Specifically, based on observed oceanographic data during the 1996 Shelfbreak Primer Experiment, the Harvard University primitive-equation ocean model is initialized with many realizations of physical fields and then integrated to produce many realizations of a five-day regional forecast of the sound speed field. In doing so, the initial physical realizations are obtained by perturbing the physical initial conditions in statistical accord with a realistic error subspace. The different forecast realizations of the sound speed field are then fed into a Naval Postgraduate School coupled-mode sound propagation model to produce realizations of the predicted acoustic wavefield in a vertical plane across the shelfbreak frontal zone. The combined ocean and acoustic results from this Monte Carlo simulation study provide insights into the relations between the uncertainties in the ocean and acoustic estimates. The modeled uncertainties in the transmission loss estimate and their relations to the error statistics in the ocean estimate are discussed.

The high charge and high energy (HZE) particle radiation environment in space interacts with spacecraft materials and the human body to create a population of neutrons encompassing a broad kinetic energy spectrum. As an HZE ion penetrates matter, there is an increasing chance of fragmentation as penetration depth increases. When an ion fragments, secondary neutrons are released with velocities up to that of the primary ion, giving some neutrons very long penetration ranges. These secondary neutrons have a high relative biological effectiveness, are difficult to effectively shield, and can cause more biological damage than the primary ions in some scenarios. Ground-based irradiation experiments that simulate the space radiation environment must account for this spectrum of neutrons. Using the Particle and Heavy Ion Transport Code System (PHITS), it is possible to simulate a neutron environment that is characteristic of that found in spaceflight. Considering neutron dosimetry, the focus lies on the broad spectrum of recoil protons that are produced in biological targets. In a biological target, dose at a certain penetration depth is primarily dependent upon recoil proton tracks. The PHITS code can be used to simulate a broad-energy neutron spectrum traversing biological targets, and it account for the recoil particle population. This project focuses on modeling a neutron beamline irradiation scenario for determining dose at increasing depth in water targets. Energy-deposition events and particle fluence can be simulated by establishing cross-sectional scoring routines at different depths in a target. This type of model is useful for correlating theoretical data with actual beamline radiobiology experiments. Other work exposed human fibroblast cells to a high-energy neutron source to study micronuclei induction in cells at increasing depth behind water shielding. Those findings provide supporting data describing dose vs. depth across a water-equivalent medium. This poster presents PHITS data suggesting an increase in dose, up to roughly 10 cm depth, followed by a continual decrease as neutrons come to a stop in the target.

The model of the cardiovascular system of A.C. Fowler and M.J. McGuinness which takes into consideration the action of baroreflex control system of blood pressure is discussed in this work. The web-integrated software environment for modeling the level of blood pressure which includes the Java Class Library is offered. 

We investigate the performance of the HemeLB lattice-Boltzmann simulator for cerebrovascular blood flow, aimed at providing timely and clinically relevant assistance to neurosurgeons. HemeLB is optimised for sparse geometries, supports interactive use, and scales well to 32,768 cores for problems with ~81 million lattice sites. We obtain a maximum performance of 29.5 billion site updates per second, with only an 11% slowdown for highly sparse problems (5% fluid fraction). We present steering and visualisation performance measurements and provide a model which allows users to predict the performance, thereby determining how to run simulations with maximum accuracy within time constraints.

We investigate the performance of the HemeLB lattice-Boltzmann simulator for cerebrovascular blood flow, aimed at providing timely and clinically relevant assistance to neurosurgeons. HemeLB is optimised for sparse geometries, supports interactive use, and scales well to 32,768 cores for problems with ~81 million lattice sites. We obtain a maximum performance of 29.5 billion site updates per second, with only an 11% slowdown for highly sparse problems (5% fluid fraction). We present steering and visualisation performance measurements and provide a model which allows users to predict the performance, thereby determining how to run simulations with maximum accuracy within time constraints.

This technique has the potential for direct observation of the clutter feature of interest and can study small scale spatial variability and isolated features, due to the small distances between the source, receiver and the clutter features. This measurement technique requires both a short transmit pulse and a vertical receive array to mitigate the problems of multipath and care must be taken to avoid contamination by sub-bottom reflections at normal incidence.

Introduction: This article was written with the objective of assessing the quality of service delivery and performance evaluation of Yazd University’s electronic library services and its user’s perception of these services along with identification of factors affecting the quality of services and these factors’ degree of importance.. Methodology: After reviewing the research literature and interviewing experts in this field, 20 failure factors in the quality of library services have been identified. After designing and distributing questionnaires among 120 users and experts in the form of failure mode and effect analysis (FMEA) approach, these failure factors were questioned in a linguistic form and intuitionistic-fuzzy environment. In the next step, these factors were ranked using VIKOR method. Eventually, using interpretation structural model (ISM), reducing barriers’ strategies were ranked. Findings: With using the described method, the factors affecting the quality of service were ranked and found that the user information retention factor with Q = 07 is in the first priority, the processing speed factor with Q = 08 is in the second priority and the factor of updating the information with Q = .15 is in the third priority. Other factors were ranked similarly. In the next stage, using the method of interpretive structural modeling, the strategies for increasing the level of service quality were ranked. The factors creating wide access to electronic journals and the non-disclosure of user information were placed at level 1. Conclusion: The users of the electronic library have focused their attention on maintaining information, due to which managers of this library should pay more attention to security and use of secure systems. Also, the processing speed that is the next priority of users requires special attention to provide the appropriate bandwidth and platform and the use of up-to-date and new technologies to provide users with the right speed and satisfaction. Also, other influential factors that have been prioritized in this study need some attention and, by doing so, the library can provide an appropriate quality for providing appropriate services and obtaining customers’ satisfaction.

This report documents the methods and findings of the Infantry Situation Awareness (SA) project, conducted to develop a model and measures of SA for the unique Infantry operational environment The research team analyzed the complexities of the Infantryman's environment based on the tactical parameters of mission, enemy, terrain, troops, time available, and civilian considerations (METT-TC) at various echelons from the individual soldier to brigade level. The analysis addressed the key factors influencing SA during various stages of operations. Available models of SA were reviewed, and two were adapted and integrated to account for individual and team SA, respectively, in Infantry operations. In addition, the research team reviewed available measures, both direct and indirect, that can be employed to evaluate individual and team SA in different operational situations and at varying echelons. The advantages, disadvantages, and application considerations for these measures were identified. The report recommends future research requirements to address Infantry SA needs related to modernization initiatives and training development efforts. Finally, the report offers suggestions to senior Army leaders concerning the value of considering SA in the development of equipment, doctrine, and training programs.

This paper describes the application of modeling and simulation in evaluating and predicting the performance of the mass storage network environment. Network traffic is generated to mimic the realistic pattern of file transfer, electronic mail, and web browsing. The behavior and performance of the mass storage network and a typical client-server Local Area Network (LAN) are investigated by modeling and simulation. Performance characteristics in throughput and delay demonstrate the important role of modeling and simulation in network engineering and capacity planning.

Estuaries, fjords and sounds are important, major components of marine ecosystems worldwide. Because of this, and their generally poor treatment by humans, large estuaries should be the focus of large-scale, multidisciplinary, integrative modeling efforts. We need to both understand how these systems work, and be able to predict how they will respond to changes, whether natural or anthropogenic. Puget Sound, Washington State's largest inland sea, is both the largest fjord in the lower forty-eight states and closest to the substantial urban centers of Seattle, Tacoma, Everett and surrounding communities. Relative to other coastal systems, Pacific Northwest fjords have seasonally high annual phytoplankton standing stock and primary production, and they support several economically valuable fisheries. Our long-term goals are to develop quantitative understanding of the seasonal and longer time-scale variability of the Sound s circulation, roles of water column stratification, nutrients, and light (and their interactions) on phytoplankton and zooplankton dynamics, and the sensitivity of the physical and the biological system to natural and human perturbations. We will develop models of Puget Sound that can aid agencies with responsibilities for environmental management in making informed decisions and serve as marine science education tools.

This article is from Journal of Cheminformatics , volume 5 . Abstract The Online Chemical Modeling Environment (OCHEM, http://ochem.eu) is a web-based platform that provides tools for automation of typical steps necessary to create a predictive QSAR/QSPR model. The platform consists of two major subsystems: a database of experimental measurements and a modeling framework. So far, OCHEM has been limited to the processing of individual compounds. In this work, we extended OCHEM with a new ability to store and model properties of binary non-additive mixtures. The developed system is publicly accessible, meaning that any user on the Web can store new data for binary mixtures and develop models to predict their non-additive properties.The database already contains almost 10,000 data points for the density, bubble point, and azeotropic behavior of binary mixtures. For these data, we developed models for both qualitative (azeotrope/zeotrope) and quantitative endpoints (density and bubble points) using different learning methods and specially developed descriptors for mixtures. The prediction performance of the models was similar to or more accurate than results reported in previous studies. Thus, we have developed and made publicly available a powerful system for modeling mixtures of chemical compounds on the Web.

Our long-term goals are to develop quantitative understanding of the Sound's circulation and marine ecosystem, and of the sensitivity of the physical and the biological system to natural and human perturbations; and to develop models of Puget Sound that can aid agencies with responsibilities for environmental management in making informed decisions and serve as marine science education tools. Our partnership will develop, maintain and operate a suite of flexibly linked simulation models of Puget Sound's circulation and ecosystem, a data management system for archiving and exchanging oceanographic data and model results that are accessible to all members of the partnership as well as to the regional and oceanographic community, and an effective delivery interface for the model results and observational data for research, education and policy formulation. Our partnership will conduct scientific research aimed at developing fundamental understanding of the Sound's working, as well as addressing practical questions raised by the regional community concerning management of the Sound and its resources. Our partnership will function as an estuarine research node within the NOPP Ocean Information Commons.

The objective of this research is to develop a mathematical model and control algorithm for maintenance of the environmental system within the Controlled Environmental Research Chamber (CERC) located at the National Aeronautics and Space Administration (NASA) Ames Research Center, Moffet Field, CA. The hypobaric research chamber is currently undergoing renovation as part of the Human Exploration Development Project (HEDP), an effort on behalf of NASA for advanced life support research. A broad overview of the chamber is provided which includes a physical description, preliminary system hardware and associated performance, and potential experimental uses. A mathematical model of the chamber air mass is developed based on key energy and mass balances. Two methods of adaptive control have been implemented for the coupled control of temperature, composition, pressure and humidity within the closed environment. Simulations testing the control algorithm performance are conducted, including a sup and modified ramp response. The results of the simulations indicate the adaptive methods performed well for the model presented. Further research is required in refining the chamber model for algorithm optimization including integration of hardware dynamics.

The objective of this research is to develop a mathematical model and control algorithm for maintenance of the environmental system within the Controlled Environmental Research Chamber (CERC) located at the National Aeronautics and Space Administration (NASA) Ames Research Center, Moffet Field, CA. The hypobaric research chamber is currently undergoing renovation as part of the Human Exploration Development Project (HEDP), an effort on behalf of NASA for advanced life support research. A broad overview of the chamber is provided which includes a physical description, preliminary system hardware and associated performance, and potential experimental uses. A mathematical model of the chamber air mass is developed based on key energy and mass balances. Two methods of adaptive control have been implemented for the coupled control of temperature, composition, pressure and humidity within the closed environment. Simulations testing the control algorithm performance are conducted, including a sup and modified ramp response. The results of the simulations indicate the adaptive methods performed well for the model presented. Further research is required in refining the chamber model for algorithm optimization including integration of hardware dynamics.

Spacecraft analysis using ORDEM2010 uses a high-fidelity population model to compute risk to on-orbit assets. The ORDEM2010 GUI allows visualization of spacecraft flux in 2-D and 1-D. The population was produced using a Bayesian statistical approach with measured and modeled environment data. Validation of sizes < 1mm were performed using Shuttle window and radiator impact measurements. Validation of sizes > 1mm is on-going.

NASA's Meteoroid Engineering Model (MEM) describes the meteoroid environment encountered by spacecraft in the inner solar system. MEM's algorithms take advantage of the fact that the vast majority of spacecraft remain close to the ecliptic plane in order to make several simplifying assumptions. However, this results in a model that cannot describe the environment for spacecraft such as Ulysses that travel far from the ecliptic, and limits the potential to validate the model using impact signatures from asteroids on inclined orbits. We are in the process of developing a new version of the code, numbered 3.1-alpha, that correctly computes the meteoroid flux and directionality far from the ecliptic. We present a new formulation of the spatial probability distribution function for fully precessed meteoroid models and compare our results with zodiacal light data.

The construction of scientific software models is an integral part of doing science, both within NASA and within the scientific community at large. Typically, model-building is a time-intensive and painstaking process, involving the design of very large, complex computer programs. Despite the considerable expenditure of resources involved, completed scientific models cannot easily be distributed and shared with the larger scientific community due to the low-level, idiosyncratic nature of the implemented code. To address this problem, we have initiated a research project aimed at constructing a software tool called the Scientific Modeling Assistant. This tool provides automated assistance to the scientist in developing, using, and sharing software models. We describe the Scientific Modeling Assistant, and also touch on some human-machine interaction issues relevant to building a successful tool of this type.

The purpose of the Simulation Product Group of the Control and Data Systems division of the NASA Engineering branch at Kennedy Space Center is to provide a realtime model and simulation of the Ground Subsystems participating in vehicle launching activities. The simulation software is part of the Spaceport Command and Control System (SCCS) and is designed to support integrated launch operation software verification, and console operator training. Using Mathworks Simulink tools, modeling engineers currently build models from the custom-built blocks to accurately represent ground hardware. This is time consuming and costly due to required rigorous testing and peer reviews to be conducted for each custom-built block. Using Mathworks Simscape tools, modeling time can be reduced since there would be no custom-code developed. After careful research, the group came to the conclusion it is feasible to use Simscape's blocks in MatLab's Simulink. My project this fall was to verify the accuracy of the Crew Access Arm model developed using Simscape tools running in the Simulink development environment.

The purpose of the Simulation Product Group of the Control and Data Systems division of the NASA Engineering branch at Kennedy Space Center is to provide a realtime model and simulation of the Ground Subsystems participating in vehicle launching activities. The simulation software is part of the Spaceport Command and Control System (SCCS) and is designed to support integrated launch operation software verification, and console operator training. Using Mathworks Simulink tools, modeling engineers currently build models from the custom-built blocks to accurately represent ground hardware. This is time consuming and costly due to required rigorous testing and peer reviews to be conducted for each custom-built block. Using Mathworks Simscape tools, modeling time can be reduced since there would be no custom-code developed. After careful research, the group came to the conclusion it is feasible to use Simscape's blocks in MatLab's Simulink. My project this fall was to verify the accuracy of the Crew Access Arm model developed using Simscape tools running in the Simulink development environment.

The Wolf-Rayet 98a (WR 98a) system is a prime target for interferometric surveys, since its identification as a "rotating pinwheel nebulae", where infrared images display a spiral dust lane revolving with a 1.4 year periodicity. WR 98a hosts a WC9+OB star, and the presence of dust is puzzling given the extreme luminosities of Wolf-Rayet stars. We present 3D hydrodynamic models for WR 98a, where dust creation and redistribution are self-consistently incorporated. Our grid-adaptive simulations resolve details in the wind collision region at scales below one percent of the orbital separation (~4 AU), while simulating up to 1300 AU. We cover several orbital periods under conditions where the gas component alone behaves adiabatic, or is subject to effective radiative cooling. In the adiabatic case, mixing between stellar winds is effective in a well-defined spiral pattern, where optimal conditions for dust creation are met. When radiative cooling is incorporated, the interaction gets dominated by thermal instabilities along the wind collision region, and dust concentrates in clumps and filaments in a volume-filling fashion, so WR 98a must obey close to adiabatic evolutions to demonstrate the rotating pinwheel structure. We mimic Keck, ALMA or future E-ELT observations and confront photometric long-term monitoring. We predict an asymmetry in the dust distribution between leading and trailing edge of the spiral, show that ALMA and E-ELT would be able to detect fine-structure in the spiral indicative of Kelvin-Helmholtz development, and confirm the variation in photometry due to the orientation. Historic Keck images are reproduced, but their resolution is insufficient to detect the details we predict.

The long-term goal is to help mitigate future potential impacts on marine mammals from sonar systems, the US Navy initiated the ESME program to explore the interaction between sound, the acoustic environment, and marine mammals. NRL was chosen by the Office of Naval Research (ONR) to be the systems integrator for the models and software developed by the government, industry, and academic researchers that comprise the ESME team.

Diffusive shock acceleration in supernova remnants is the most widely invoked paradigm to explain the Galactic cosmic ray spectrum. Cosmic rays escaping supernova remnants diffuse in the interstellar medium and collide with the ambient atomic and molecular gas. From such collisions gamma-rays are created, which can possibly provide the first evidence of a parent population of runaway cosmic rays. We present model predictions for the GeV to TeV gamma-ray emission produced by the collisions of runaway cosmic rays with the gas in the environment surrounding the shell-type supernova remnant RX J1713.7-3946. The spectral and spatial distributions of the emission, which depend upon the source age, the source injection history, the diffusion regime and the distribution of the ambient gas, as mapped by the LAB and NANTEN surveys, are studied in detail. In particular, we find for the region surrounding RX J1713-3946, that depending on the energy one is observing at, one may observe startlingly different spectra or may not detect any enhanced emission with respect to the diffuse emission contributed by background cosmic rays. This result has important implications for current and future gamma-ray experiments.

Available from National Technical Information Service, Springfield, Va

This study examined how constructivist teaching and the organization of the learning environment relate to student achievement. The researchers used structural equation modeling (SEM) to examine the relationships among school and teaching attributes and student achievement in reading, writing, and mathematics as measured by the Washington Assessment of Student Learning (WASL). Data came from the average school-level scale scores of 79,494 students and from questionnaires completed by 4,307 teachers from 239 elementary, middle/juniors, and high schools in Washington state. The analyses show a strong positive relationship between school attributes and constructivist teaching. Schools that emphasize parental and community involvement and that have teaching staff who model and expect responsible behavior and mutual respect are more likely to have staff who use constructivist teaching methods. Constructivist teaching appears to have a meaningful influence on student achievement as measured by the WASL. Findings also show structural relationships among many school and classroom factors and student achievement. Maximizing achievement appears to be the result of an environmental shift in the school, a reinvention of education. (Contains 4 figures and 19 references.) (SLD)

This study examined how constructivist teaching and the organization of the learning environment relate to student achievement. The researchers used structural equation modeling (SEM) to examine the relationships among school and teaching attributes and student achievement in reading, writing, and mathematics as measured by the Washington Assessment of Student Learning (WASL). Data came from the average school-level scale scores of 79,494 students and from questionnaires completed by 4,307 teachers from 239 elementary, middle/juniors, and high schools in Washington state. The analyses show a strong positive relationship between school attributes and constructivist teaching. Schools that emphasize parental and community involvement and that have teaching staff who model and expect responsible behavior and mutual respect are more likely to have staff who use constructivist teaching methods. Constructivist teaching appears to have a meaningful influence on student achievement as measured by the WASL. Findings also show structural relationships among many school and classroom factors and student achievement. Maximizing achievement appears to be the result of an environmental shift in the school, a reinvention of education. (Contains 4 figures and 19 references.) (SLD)

This study examined how constructivist teaching and the organization of the learning environment relate to student achievement. The researchers used structural equation modeling (SEM) to examine the relationships among school and teaching attributes and student achievement in reading, writing, and mathematics as measured by the Washington Assessment of Student Learning (WASL). Data came from the average school-level scale scores of 79,494 students and from questionnaires completed by 4,307 teachers from 239 elementary, middle/juniors, and high schools in Washington state. The analyses show a strong positive relationship between school attributes and constructivist teaching. Schools that emphasize parental and community involvement and that have teaching staff who model and expect responsible behavior and mutual respect are more likely to have staff who use constructivist teaching methods. Constructivist teaching appears to have a meaningful influence on student achievement as measured by the WASL. Findings also show structural relationships among many school and classroom factors and student achievement. Maximizing achievement appears to be the result of an environmental shift in the school, a reinvention of education. (Contains 4 figures and 19 references.) (SLD)

This study examined how constructivist teaching and the organization of the learning environment relate to student achievement. The researchers used structural equation modeling (SEM) to examine the relationships among school and teaching attributes and student achievement in reading, writing, and mathematics as measured by the Washington Assessment of Student Learning (WASL). Data came from the average school-level scale scores of 79,494 students and from questionnaires completed by 4,307 teachers from 239 elementary, middle/juniors, and high schools in Washington state. The analyses show a strong positive relationship between school attributes and constructivist teaching. Schools that emphasize parental and community involvement and that have teaching staff who model and expect responsible behavior and mutual respect are more likely to have staff who use constructivist teaching methods. Constructivist teaching appears to have a meaningful influence on student achievement as measured by the WASL. Findings also show structural relationships among many school and classroom factors and student achievement. Maximizing achievement appears to be the result of an environmental shift in the school, a reinvention of education. (Contains 4 figures and 19 references.) (SLD)