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This book aims to present an introduction to numerical modeling of different aspects of large-scale superconducting applications: electromagnetics, thermal, mechanics and thermo-hydraulics. The importance of computational modeling to advance current superconductor research cannot be overlooked, especially given the enormous benefits provided by superconductors in many human endeavours, including energy generation, medical treatments, and future electrical technologies.Aimed at graduate students, researchers and practitioners in different fields of applied superconductivity, this book consists of four chapters. The chapter on electromagnetics provides a review of the state-of-the-art modeling of electromagnetic phenomena in superconductors, emphasising the theoretical aspects of the different numerical formulations. This is followed by a chapter on thermal effects, dedicated to the simulation of thermal stability and quench in superconducting magnets, with specific examples of magnets used in particle accelerators. Then, the chapter on mechanics provides details of the modeling of forces and stresses in cables composed of second-generation high-temperature superconducting wires. Finally, the chapter on thermo-hydraulics focuses on the fundamental thermal-hydraulic aspects involved in the cooling of superconducting magnets, with special reference to the issues related to the forced-flow cooling.

This book aims to present an introduction to numerical modeling of different aspects of large-scale superconducting applications: electromagnetics, thermal, mechanics and thermo-hydraulics. The importance of computational modeling to advance current superconductor research cannot be overlooked, especially given the enormous benefits provided by superconductors in many human endeavours, including energy generation, medical treatments, and future electrical technologies.Aimed at graduate students, researchers and practitioners in different fields of applied superconductivity, this book consists of four chapters. The chapter on electromagnetics provides a review of the state-of-the-art modeling of electromagnetic phenomena in superconductors, emphasising the theoretical aspects of the different numerical formulations. This is followed by a chapter on thermal effects, dedicated to the simulation of thermal stability and quench in superconducting magnets, with specific examples of magnets used in particle accelerators. Then, the chapter on mechanics provides details of the modeling of forces and stresses in cables composed of second-generation high-temperature superconducting wires. Finally, the chapter on thermo-hydraulics focuses on the fundamental thermal-hydraulic aspects involved in the cooling of superconducting magnets, with special reference to the issues related to the forced-flow cooling.

A far-field beam pattern or directivity function of a conformal acoustic array can be generated by performing a three dimensional spatial discrete Fourier transform of the array’s aperture function. The beam pattern is a function of frequency, and both spherical angles of direction. It is strongly dependent on the aperture window, on the applied time delays, and the geometrical configuration of the array. A user-friendly micro-computer software program was created to study the actual array design and the degraded array. The program generates tabular and graphical data in a short period of time (3 min.) for a given frequency, bearing angle (MRA), speed of sound and configuration. Finally, this thesis shows that the degradation of even a few elements seriously influences the sensitivity and the shape of the beam pattern, and the users must draw conclusion on an individual basis.

A far-field beam pattern or directivity function of a conformal acoustic array can be generated by performing a three dimensional spatial discrete Fourier transform of the array’s aperture function. The beam pattern is a function of frequency, and both spherical angles of direction. It is strongly dependent on the aperture window, on the applied time delays, and the geometrical configuration of the array. A user-friendly micro-computer software program was created to study the actual array design and the degraded array. The program generates tabular and graphical data in a short period of time (3 min.) for a given frequency, bearing angle (MRA), speed of sound and configuration. Finally, this thesis shows that the degradation of even a few elements seriously influences the sensitivity and the shape of the beam pattern, and the users must draw conclusion on an individual basis.

In this article, multiple collisions for two-dimensional (planar) open-loop robotic systems, which are formed by n elastic links with rotational joints, have been studied.The dynamic motion equations of this system have been done by the Gibbs-Appell recursive algorithm and modeling the impact-contact phenomenon by regulized method. Timoshenko's beam theory has been used to model transverse vibrations of links. Also, to increase the accuracy of modeling, the effects of structural damping and air damping have been considered.The joints are without backlash and friction, but the friction force is included in the place where the links meet the ground. The movement of the system has two phases: flight and collision.The differential equations of the system in the collision stage include terms caused by viscoelastic forces, which result in new equations of motion. These new differential equations are very difficult due to the nature of the collision force, and solving them in a very short collision time requires special measures.Due to the very short time of collision, accurate detection of the moment of collision is very important. For this purpose, entry into the collision phase and exit from it is controlled with a very high precision with the special calculation algorithm presented in this article.To show the efficiency and accuracy of the developed program, computer simulations have been performed to study the dynamic behavior of a three-link robotic system.

The objective of this thesis is to evaluate a modeling and simulation tool for the analysis of the Trident II D5 missile nose fairing to determine the limitations of serviceability through the extended service life of the D5 missile. The benefit of this analysis is a means to evaluate and manage the remaining nose fairing supply and serve as a baseline for future production of nose fairings. Constructed of a Sitka spruce and fiberglass laminate, the nose fairing is designed as the lifting point of the missile for submarine onloads and offloads and supports the entire weight of the missile. A computer model of the nose fairing was used to evaluate the nose fairing under tensile and compressive loading conditions to simulate the lifting evolution and closure segment impact at time of launch. Changes in the material properties of the model allow for a simulation of aging in the nose fairing to estimate the performance degradation over time, as well as exploration of the applicability of new materials to any future design of nose fairings.

We investigated utilizing serious games to train officers on Navy operational staffs, such as carrier strike groups (CSGs), destroyer squadrons (DESRONs), and amphibious squadrons (PHIBRONs). Such staffs are composed of officers from different warfare communities, such as aviation, submarines, and surface warfare. Most have not served on such a staff before and have limited familiarity with the inner workings and responsibilities of their command. We reviewed the current standards of training and serious games usage, and designed an experiment to determine whether serious games could provide a statistically significant improvement in training transfer for deployable staff officers compared to traditional methods of training. The experiment group was composed of West-Coast watchstanders. They played two different scenarios on two separate gaming applications for a total of four sessions. We compared performances between the experimental group and control group using a pre-test and a post-test given after the training. We also conducted another test one month later to see if a difference existed in long-term retention. The control group was enrolled in the joint maritime tactics course, using classroom lectures administered by Tactical Training Group, Atlantic. Small sample size merited nonparametric statistics usage, which increased the difficulty of obtaining significant results. Only one test produced a significant outcome, but the results feed into demand for future work.

The aim of this work is to describe the physics-based simulation model of a custom 3D range laser scanner together with generic interface which offers the possibility for client applications to seamlessly interact with instances of the physical and virtual 3D range scanner. The physics-based virtual model of the 3D range scanner is realized in rigid body dynamics environment provided by Open Dynamics Engine (ODE) library. In order to simulate the stepper motor used in the real scanner, the joints are virtually constrained and motorized with the parameters obtained from real device. For rays modeling the ray-cast method is used. The incidence angle and the surface properties of the object hit by the rays are also taken into the consideration. The sensor noise that represents the uncertainty of the measure is also taken into account. We have also tried to mimic the internal sensor control logic. In order to verify the developed model and the interface architecture, a simple client application for 3D data acquisition is developed and connected through the same interface to both “physical” and “virtual” device. The results of the evaluation are also reported and discussed.

Network Function Virtualization (NFV) takes advantage of hardware virtualization to undertake software processing for various functions, and complements the drawbacks of traditional network technology. To speed up NFV related research, we need a user friendly and easy to use research tool, which could support data center simulation, scheduling algorithms implementation and extension, and provide energy consumption simulation. As a cloud simulation toolkit, CloudSim has strong extendibility that could be extended to simulate NFV environment. This paper introduces a NFV cloud framework based on CloudSim and an energy consumption model based on multi-dimensional extension, implementing a toolkit named ClousimNFV to simulate the NFV scenario, proposing several scheduling algorithm based on for NFV applications. The toolkit validation and algorithm performance comparison are also given.

The mathematical modeling and numerical simulation of semiconductor-electrolyte systems play important roles in the design of high-performance semiconductor-liquid junction solar cells. In this work, we propose a macroscopic mathematical model, a system of nonlinear partial differential equations, for the complete description of charge transfer dynamics in such systems. The model consists of a reaction-drift-diffusion-Poisson system that models the transport of electrons and holes in the semiconductor region and an equivalent system that describes the transport of reductants and oxidants, as well as other charged species, in the electrolyte region. The coupling between the semiconductor and the electrolyte is modeled through a set of interfacial reaction and current balance conditions. We present some numerical simulations to illustrate the quantitative behavior of the semiconductor-electrolyte system in both dark and illuminated environments. We show numerically that one can replace the electrolyte region in the system with a Schottky contact only when the bulk reductant-oxidant pair density is extremely high. Otherwise, such replacement gives significantly inaccurate description of the real dynamics of the semiconductor-electrolyte system.

This report documents the research conducted under AFOSR Grant F4962O-92-J0488, 'Compressible Flow Turbulence Simulation and Modeling via Additive Turbulent Decomposition,' during the period 09/01/92-11/30/95. We begin by noting that four graduate students have been supported during the course of this grant: Mr. D. Denger, Ms. S. Flynn, Mr. E. C. Hylin and Mr. D. C. Weatherly. The first two chose to leave the project before the end of the first year; Ms. Flynn received her M.S. in Mechanical Engineering shortly thereafter, and Mr. Denger is expected to receive his Ph.D. in Mechanical Engineering at least by the end of Summer 1996. Both of the remaining two students, Mr. Hylin and Mr. Weatherly, anticipate completing their Ph.D.s in Mechanical Engineering during the current semester, Spring '96. Thus, the grant will have aided, very crucially in the latter two cases, in producing four advanced engineering degrees. (AN)

Minnesota high school students and teachers are learning the technology of simulation and integrating it into business and industrial technology courses. Modeling and simulation is the science of using software to construct a system within an organization and then running simulations of proposed changes to assess results before funds are spent. In partnership with PROMODEL Corporation, the Southeast Service Cooperative is helping schools and communities in primarily rural southeast Minnesota to develop partnerships that make local businesses more globally competitive. School teams work with a local business or agency to identify a system that the organization wants to analyze. It may involve solving an operational problem, designing a new facility, or simply exploring possible improvements. The team compiles data from the partner to construct an animated model of the system and then runs "what if" simulations. Students develop a variety of communication, research, and technology skills, as well as an understanding of their community's economic development. Teachers can integrate the program into existing classes or offer it as a separate class. This paper describes how a modeling and simulation project might work, lists hardware and software requirements and costs, briefly profiles school-community projects in Minnesota small towns, outlines program benefits and relevance to Minnesota graduation requirements, and provides contact information. A Power Point slide presentation provides additional information. (SV)

This document deals with modeling and stimulation. The strengths are study processes that rarely or never occur, evaluate a wide range of alternatives, generate new ideas, new concepts and innovative solutions. A dilemma is to provide rapid response to decisionmakers and adequate visibility to know how to implement recommendations. Weaknesses are the time needed to complete comprehensive work and the current state of data management.

A team of researchers from the Air Force Research Laboratory, Northrop Grumman and Stanford University have conducted organizational research over the past few years; out of this research has grown modifications to simulation software that was utilized by the team to study a planning organization. This paper describes the results from studying organizational change using simulation software, and comparing results against a revised software package to the original design. This line of research was started by the Virtual Design Team (VDT) research group; initiated at Stanford University in the late 1980s to help managers design organizations and work processes for executing fast-track development of complex products. VDT is an agent-based computational model of a project team and a set of work processes they are attempting to execute in a concurrent manner. VDT has been successfully used to model work activities, communications, and exception handling within traditional organizations working on projects in areas such as construction, aerospace, consumer product development, and healthcare. From the VDT work Stanford University built the Project Organization Workflow model for Edge Research (POWER) software. This software was used to study Edge organizations. The current laboratory, Stanford University, and Northrop Grumman team modified the POWER software and developed Project Organization Workflow model for Information Development (POW-ID), used to develop the models and results shown in this paper.

Inventory reduction is one of the most critical areas facing DoD in this era of diminishing resources and increasing global commitments. This thesis analyzes the concept of cycle time reduction as a significant method to reduce inventory levels. The order fulfillment process of a distribution center is analyzed using simulation modeling and business process reengineering (BPR) concepts. The two simulation models were designed and evaluated by measuring the cycle time of an order flowing through the distribution center. The results indicate that the cycle time of the order fulfillment process can be reduced by 90%, inventory levels reduced by 77% with a labor savings of $60,000. This was achieved by reengineering the order fulfillment process from a batch system to one that sends incoming orders directly to the warehouse for order selection. The implications for the DoD are critical to the goal of inventory reduction; by focusing on the reduction of cycle time, in-process inventories are also be reduced. The use of business process reengineering and simulation modeling offer powerful tools to aid the manager in reducing cycle time and inventory levels.

We propose augmentation of the principal investigator's parent contract with the Air Force in the form of support for one additional graduate student. The student would perform numerical simulations and modeling relevant to the use of ultrashort optical pulses to observe a remote object at high data rate. The work would relate specifically to our recent experimental demonstration of a kinematically modelocked nonlinear loop mirror laser utilizing erbium doped fiber. This technology provides a strategy for realizing a sensitive means for sensing the motion of a remote object. The student would seek a better description of the internal dynamics of the nonlinear loop mirror laser and would examine strategies that might more fully utilize the potential of this physical behavior. Relevance to recent and ongoing work would also be addressed.

This report covers Phase III of the work of the Defense Science Board (DSB) Task Force on Missile Defense. Phase I examined mid-course discrimination. Phase II, a 2002 DSB Summer Study, examined the four issues shown in the chart above. Following completion of the Phase II report, the Director, Missile Defense Agency (MDA) asked the Task Force to examine modeling and simulation (M&S). The Under Secretary Defense for Acquisition, Technology and Logistics (USDAT&L) concurred. The request was further refined to the five areas shown. After a brief introduction, this report will cover each of the five issues in turn.

There is concern within U.S. space and intelligence organizations that the current Tasking, Processing, Exploitation, and Dissemination processes may be insufficient to support current and future Intelligence, Surveillance, and Reconnaissance systems. As part of a larger intelligence process, more detailed analysis becomes critical to determine what portions need to be improved. This analysis can be accomplished by simulation, which is appropriate due to the complexity of the process and the ability to compare variations in the process. We construct a high level model of a generalized military intelligence process based in part on the Intelligence Cycle outlined in Joint Publications. Using the Arena process oriented simulation software, our modular simulation can be used for quick turn studies on changes to the process, specifically with respect to classical measures such as quality, quantity, and timeliness. A sample study using the basic framework of the intelligence process with statistical analysis is also conducted.

This project simulates QPSK modulation signals and uses a laboratory environment to create deteriorating effects of real-world high frequency (HF) transmissions that may modify the ideal QPSK waveform. These modifications may be identifiable in order to fingerprint the source of the modifications. To simulate the transmission path in the real world a signal generator is used to create the QPSK I/Q signal at the HF operating frequencies and a digital sampling oscilloscope acts as a receiver and records the data for analysis. A computer with MATLAB Instrument-control Toolbox is used to generate a random-input data stream as an input to the signal generator, which modulates the RF signal. The RF signal was chosen to be at HF (5-15 MHz) and the QPSK modulation was at 9600 baud. The deterioration effects of a real-world transmitter site were chosen to be associated with the output amplifier linearity and

The future DoD transport vision is for the Global Information Grid (GIG) to provide an internet-like capability that meets the mobility, security, and reliability needs of a wide spectrum of DoD users. A variety of services must be provided to the users including management of resources to support QoS, a transition path from IPv4 to IPv6, and efficient networking across heterogeneous networks (i.e., wired/wireless, fixed/mobile, GND/Air/Space, etc.). Due to the complexity of the issues involved with the integrated GIG, it is only possible to quantify end-to-end GIG performance via modeling and simulation (M&S) techniques using component models having adequate fidelity. The purpose of this paper is to describe the End-to-End M&S Testbed (EMAST) that has been developed to address these issues.

The goals are to develop Tactical Decision Aids (TDAs) for using small autonomous underwater vehicles in very shallow water (VSW) environments. TDAs enable operators to view data gathered by these vehicles and make informed decisions as to the conduct of mine counter measures operations. This project is examining the use of command and control vehicles to aid in reducing latency of decision making and improvements to overall MCM reliability using multiple vehicles.

In the past thirty years, weapon systems development costs have been steadily increasing with each succeeding system costing mow than the last one. In fact, the cost of developing a new weapons system may become a factor in deciding whether a new system is procured or not. Clearly, there is a need to reduce the cost of developing new military systems. Besides the obvious benefit of saving real dollars at the most critical point in a weapon system's life cycle, lowering development costs could help tip the scales in favor of developing a new system as opposed to modifying an existing system. Studies have shown that a new system usually offers significant capability and performance benefits, as well as cost benefits, over those of a derivative weapons system. Reducing the cost of developing new weapons systems also can mean that mow systems could be developed within a constrained budget, a situation that is most favorable to sustaining our industrial base. A new weapon system, rather than a derivative or modification also offers the best opportunity for technology advancement and for technology transition into the hands of the nation's warfighter.

The flow behaviors of polymer melt composed of short chains with ten beads between parallel plates are simulated by using a hybrid method of molecular dynamics and computational fluid dynamics. Three problems are solved: creep motion under a constant shear stress and its recovery motion after removing the stress, pressure-driven flows, and the flows in rapidly oscillating plates. In the creep/recovery problem, the delayed elastic deformation in the creep motion and evident elastic behavior in the recovery motion are demonstrated. The velocity profiles of the melt in pressure-driven flows are quite different from those of Newtonian fluid due to shear thinning. Velocity gradients of the melt become steeper near the plates and flatter at the middle between the plates as the pressure gradient increases and the temperature decreases. In the rapidly oscillating plates, the viscous boundary layer of the melt is much thinner than that of Newtonian fluid due to the shear thinning of the melt. Three different rheological regimes, i.e., the viscous fluid, visco-elastic liquid, and visco-elastic solid regimes, form over the oscillating plate according to the local Deborah numbers. The melt behaves as a viscous fluid in a region for $\omega\tau^R\lesssim 1$, and the crossover between the liquid-like and solid-like regime takes place around $\omega\tau^\alpha\simeq 1$ (where $\omega$ is the angular frequency of the plate and $\tau^R$ and $\tau^\alpha$ are Rouse and $\alpha$ relaxation time, respectively).

Half-symmetric model is used in AutoDyn to simulate Depth of Penetration (DoP) experiments on SiC tile with and without a gap supported by solid aluminum. Impacts of a .30cal AP M2 projectile over an impact velocity range 700 m/s to 1000 m/s are modeled using SPH elements. Model validation runs with monolithic SiC tiles are conducted based on the DoP experiments described in reference - ARL-TR-2219, 2000. Tile gap is found to increase the DoP as compared to monolithic tiles. The next step will be run simulations on narrower and wider gap sizes and different geometries of tile configurations. Determinations need to be made on what the manufacturers tolerances on tile gaps are and possible filling materials for gaps. DOP is the main measurement to determine which geometry and configuration yield the best results.

The Network Centric Warfare approach to command and control emphasizes decentralized decision making. Consequently, decision makers must comprehend and evaluate information to determine the optimal course of action. This study examines how different categories of uncertainty (ambiguous/missing, conflicting, baseline) and individual differences affect response time in decision-making tasks. The researchers elicited real-world tactical scenarios from veterans of Operation Enduring Freedom and Operation Iraqi Freedom in which uncertainty was present. Nine scenarios were given to 28 participants at the Command General Staff College, Fort Leavenworth, Kansas. The participants were asked to make a decision; their responses were recorded and analyzed. The results indicate that category of uncertainty and scenario difficulty are significant factors in determining response time. No individual difference factors were found to be significant. These findings have the potential to improve human behavior modeling, tactical simulations, and representations of complex task environments.

This project employs modeling and simulation analysis in an effort to assess various aspects of the Marine Aviation Logistics Support Program II (MALSP II) doctrine currently in development. MALSP II leverages recent innovations in information technology, logistics chain management, and continuous process improvement in order to improve logistical support to deployed Marine air assets. The model develop in this project is a Discrete Event Simulation, implemented in Java using the SimKit programming libraries. It is employed to specifically analyze aspects of MALSP II doctrine; however, it is sufficiently flexible to analyze various aspects of Legacy MALSP concepts as well. The model is relatively straightforward and has a small number of inputs. In most cases, sufficient data exist to confirm the suitability of modeling a given empirical distribution in a particular manner. In some instances where data are more difficult to obtain, compelling theoretical reasons exist as justification for selecting a particular distribution or algorithm.

-Develop Modeling and Simulation tools, use Depth of Penetration (DOP) as metric, 7.62 APM2 -Evaluate SiC tile on Aluminum with material properties from literature -Develop seam designs to improve performance, demonstrate with DOP experiments (tiles from Supplier, sintered SiC) 15.

The work described in this paper addresses recent advances in the application of modeling and simulation (M&S) techniques to the problem of quantifying the force-level warfighting value-added of Information Superiority (IS) and Network Centric Warfare (NCW) in the context of realistic scenarios including Operational War Plans (OPLANs). The IS/NCW M&S activities to be reported in this paper have taken place in support of operational experiments and wargames, as part of analyses in support of CINC-level commands, and as a part of analyses in support of certain specific acquisition programs having the requirement to demonstrate synergy with ongoing DoD/Service Information Technology/Network Centric Warfare (IT/NCW) improvement programs. Lessons-learned concerning the challenges associated with representing IT infrastructure improvements along with required NCW warfare process reengineering (WPR) initiatives will be presented. It will be shown that an iterative cycle of WPR initiative formulation and evaluation is often a required part of an assessment of the force-level warfighting value-added of specific IT/NCW improvements. We have found that M&S tools hence provide an important adjunct to operational experimentation in the role of formulating and evaluating the WPR initiatives which will likely provide the most warfighting value-added for specific IT improvements relative to specific scenarios or war plans. Quantitative results, including discussion of specific sets of analyzed IT improvement(s), WPR initiative(s), and OPLANs, will be included in this paper.

A computational model of Standing Joint Force Headquarters (SJFHQ) processes was developed using EXTEND simulation software. In this paper we describe the use of this modeling and simulation approach for analyzing time-critical information systems and performing trade studies. An object-oriented model was constructed of the processes performed by SJFHQ members and simulations were run to obtain system measures of performance. This model focuses on the planning processes performed by SJFHQ members to support the Effects-Based Planning processes and the Operational Net Assessment update. A complete four-level architecture was developed that captures all processes, sub-processes, information flows, and personnel task assignments. It includes detailed architectures and was based on US Joint Forces Combined publications and subject-matter expertise.

The purpose of this document is to lay out a plan for research on Crowd Control Modeling and Simulation. Models and simulations that predict or describe crowd behavior do not exist at the present time in a form that could be used to describe the dynamics of crowds and how the use of NLWs will impact their behavior. In order to provide proper training and a dependable range of options to warfighters, effective M&S techniques, which incorporate recent and reliable data on human behavior and computer generated forces (CGF), must be developed. The JNLWD will be able to develop a set of usable tools in a shorter time period, and at a lower cost, if a coordinated plan is maintained and executed that leverages research currently being supported by the JNLWD and other agencies.

We investigate the performance of a Liquid Crystal (LC) Spatial Light Modulator (SLM) as an optical device for generating high intensity atmospheric turbulence in the laboratory. The experimental setup represents long range horizontal beam propagation at a low altitude where the conditions of atmospheric turbulence can be most severe. WaveProp is a software package written by the Optical Sciences Company (tOSC) which is used for simulating electro-magnetic field propagation through equally spaced phase screens. This simulation tool provides the cumulative amplitude and phase modulation input signals to a single LC SLM. An SLM is configured at the Naval Postgraduate School (NPS) Adaptive Optics Center of Excellence to modulate both amplitude and phase simultaneously. The SLM reproduces large amplitude fluctuation with branch points and branch forks from the deep turbulence models. Deep horizontal path laser propagation reported herein is modeled and simulated in the NPS laboratory to provide realistic optical disturbances for an adaptive optics wavefront correction system.

Artificial systems that generate contingency-based teleological behaviors in real-time, are difficult to model. This chapter describes a modeling and simulation (M&S) framework designed specifically to reduce this difficulty. The described Knowledge-based Contingency-driven Generative Systems (KCGS) framework combines aspects of SES theory, DEVS-based general systems theory, net-centric heterogeneous simulation, knowledge engineering, cognitive modeling, and domain-specific language development using meta-modeling. The chapter outlines the theoretical and technical foundations of the KCGS framework as realized in the Cognitive Systems Specification Framework (CS2F), a subset of KCGS. Two executable models are described to illustrate how models of autonomous, goal-pursuing cognitive systems can be modeled and simulated in the framework. The technical content and agent descriptions in the chapter illustrate how the M&S of the artificial depends critically on ontology, epistemology, and teleology in the KCGS framework.

This report describes an investigation of modeling and analysis of two-phase flow in the condenser of a vapor-compression refrigeration system. The approach used a novel in-house code for the analysis of two different film condensation problems: a) underside of a horizontal plate, b) in a plane channel. In the first study, the effect on heat transfer was determined at various degrees of sub-cooling of the plate and at various unsteady flow regimes using R-123 and n-pentane as working fluids. The second study was done analytically for fully-developed and numerically for developing flow in a channel; excellent agreement between the two results was observed in the fully developed region. Simulations were done for four different cases, consisting of various standard thermal boundary conditions on the channel wall. Numerical results obtained for the developing flow are consistent with the physical-model and operating-conditions proposed in the present work. The findings from this fundamental modeling and simulation study can be extended to model and analyze condenser flow for better design and integration in thermal-management systems found in aircraft.

To aid in the development of the control strategy and the fault detection/fault isolation logic for a self-contained wastewater treatment system, a dynamic model of the system has been developed. The model integrates component models for water processing units into a process simulator to facilitate the simulation of a variety of configurations for water reuse processes. This report describes the simulator modules, the use of the simulator, and the details of input data preparation. (Author)

The objective of this research is to develop techniques for more easily building simulation models with resolution levels appropriate for their purpose. The basic premise was that a modular, hierarchial modeling approach would be best suited to accomplish this and that object oriented programming techniques would be a primary enabling technology. Within the proposed hierarchial modeling framework, submodels may be represented in either their original form or in an aggregated form, the choice of being governed by the goals and constraints of a particular simulation study. In this paper a prototype hierarchial modeling system supporting aggregation is presented. The prototype was coded in the SMALL-TALK-80 object oriented programming environment, and is tailored to an airbase logistics application. The paper also discusses several possible approaches to aggregation, concluding that the simulative approach is most appropriate for this application.

This document presents a tutorial describing aspects of the coding of computerized simulations of models of visual cortical development. The model considered has an anatomy of an excitatory projection from thalamus to cortex combined with intracortical inhibition. Cortical cells develop specificity to stimulus patterns in this model only when appropriate experience enables synaptic modification to organize the network. The simulation consists of a time loop. For each iteration of this loop, a stimulus is generated, the cortical response to this stimulus is computed, and synaptic weights are modified. The developing network is tested intermittently and the behavior of the system analyzed. Some of the details of the coding given include a method of describing rearing conditions, a convenient abstract form for the input stimuli, an iterative calculation of the intracortical feedback, a simple way to store synaptic strengths, and routines for performing the analysis. Keywords: numerical methods and procedures; plasticity.

Defence R and D Canadas Centre for Security Science (CSS) is working in partnership with Public SafetyCanada (PS) on a long term objective to develop an integrated national and regional CriticalInfrastructure (CI) Dependency model for CI risk analysis and risk mitigation in support of the 2010National Critical Infrastructure Strategy. To frame discussions and serve as a starting point, CSS hasrequested NRC Knowledge Management to perform an exploratory study of existing scientific, industrialand government (domestic/international) literature on critical infrastructure protection and resilience(CIPR) and related concepts; including, but not limited to, CI interdependencies as well as modeling andsimulation tools.This report focuses on modeling and simulation tools and trends. In all, 2,151 publications, including asub dataset of 633 publications specifically focused on interdependency modeling and simulation, wereretrieved and analyzed using text mining software and a variety of visualization tools to identify trendsin the literature and key players. Additionally a listing of 113 tools found in the dataset are alsoprovided, among which 82 tools focused on interdependency modeling or simulation, 18 focused onregional or local modeling or simulation, and 13 focused on government/business continuity modelingand simulation with some repeats between groups. Government/business continuity tools are usedmost frequently to model and simulate CIPR in the Energy and Utilities and Water sectors.

Peridynamics is a nonlocal formulation of continuum mechanics in which forces are calculated as integral functions of displacement fields rather than spatial derivatives. The peridynamic model has major advantages over classical continuum mechanics when displacements are discontinuous, such as in the case of material failure. While multiple peridynamic material models capture the behavior of solid materials, not all structures are conveniently analyzed as solids. Finite Element Analysis often uses 1D and 2D elements to model thin features that would otherwise require a great number of 3D elements, but peridynamic thin features remain underdeveloped despite great interest in the engineering community. This work develops nonordinary state-based peridynamic models for the simulation of thin features. Beginning from an example nonordinary state-based model, lower dimensional peridynamic models of plates, beams, and shells are developed and validated against classical models. These peridynamic models are extended to incorporate brittle and plastic material failure, compounding the peridynamic ad- vantages of discontinuity handling with the computational simplicity of reduced- dimension features. These models will allow peridynamic modeling of complex structures such as aircraft skin that may experience damage from internal forces or external impacts.

This report, consisting of all viewgraphs, describes the Department of Defense Modeling and Simulation Policy update, which includes a perspective, vision and role of DMSO, user's dilemma regarding data, organizational structure, implementating the policy, transition examples and community support for the DMSO vision and role.

The Naval Research Laboratory conducted an extensive in-person survey of the Navy and Marine Corps modeling and simulation (M&S) community's digital Mapping, Charting, and Geodesy (dMC&G) and value-added data requirements during late 1992 and early 1993. Simultaneously, the Air Force, the Army, and the National Security Agency (NSA) conducted similar studies for their respective services/agencies. Over 100 programs responded to this Navy study. This report presents an analysis of the collected requirements and emphasizes identifying feature, attribute, and value-added information that the M&S community requires but that is currently not available. Attention is given to required modifications to existing DMA dMC&G products. This report seeks to identify modifications to emerging and existing DMA products needed for optimum use by the Navy M&S community, and focuses only on the changes and improvements. (MM)

The purpose of this document is to provide to DRTWO members notes of the February 7-10 Defense Modeling and Simulation Office (DMSO) Data and Repositories Technology Working Group (DRTWG) meetings, and notes from other DRTWG Task Force and Subgroup meetings held since the previous I/DBTWG meeting in July 1994. In addition, it provides information to people who wish to participate in the DRTWO and those with an interest in data activities related to modeling and simulation. (KAR) P. 10

Includes bibliographical references

The Optimized Network Engineering Tool (OPNET) is a commercially available communications network simulation package. This thesis involves the modification of OPNET's Fiber Distributed Data Interface Local Area Network (FDDI LAN) model in order to enhance its usefulness as an aid in the development of recommendations for the characteristics and metrics to be eventually included in the Defense Service Project Office's (DSPO) Common Data Link (CDL) project. This work includes a step-by-step guide for FDDI simulation in OPNET, and a discussion of the changes made to the original model to enhance its performance and data display characteristics. Simple tests are provided to verify the completed model's performance and usefulness as a working tool for further development.

Major research goals for this STTR project in Phase I were (a) development of a high-resolution process model suitable for high pressure crystal growth (HPCG), (b) special experiments for thermophysical property measurement, and (c) a preliminary design of an advanced HPCG furnace to transfer the DoD technology of "one-step in-situ synthesis and MLEK growth of InP crystals" for commercialization. An extraordinary progress was made in all of these areas. Several meetings were held with Rome Laboratory researchers to identify the shortcomings of the prsent furnace and needs for the future generation high pressure systems. A computer model, MASTRAPP was developed that is better than all other existing numerical models for multiphase, multicomponent processes with moving boundaries and free surfaces. MASTRAPP2d with a reference manual is now available for distribution to the interested groups of researchers. New experiments were designed to obtain property data for InP density, thermal conductivity, electrical resistivity and phosphorus vapor pressure. A preliminary design for an advanced HPCG furnace was developed based on these experiments, extensive HPCG simulations and process details from Rome Laboratory. jg p1

Concentrating photovoltaics is a type of solar photovoltaic technology that relies on sunlight concentrating to produce electrical energy. In this regard, high-efficiency solar cells comprise many different materials cells, and energy band gaps are stacked respectively on top of each other. This technology, depending on a large portion of the solar spectrum component, which absorbed by the triple-junction solar cell; the consequence is a rise in the device’s conversion efficiency. The layers of semiconductor materials, including GaInP/GaInAs/Ge, are coupled in series to gain high efficiency. Besides, an accurate assessment of the energy yield from a concentrating photovoltaic (CPV) device throughout its lifetime and the electrical performance characteristics in different operating environments is required. Hence, an MSCS-1D: V-2 solar cell simulator tool and a system advisor model (SAM) are used to model and simulate performance behavior. In this paper, we modeled and simulated mini solar concentrating photovoltaics. Based on that, solar CPV technology can be implemented in such regions to generate electricity and heat. Moreover, the selected region has a great potential for direct normal irradiations (DNI) annually. In addition, that encourages further study via applying large-scale in the form of CPV power plants.

The authors have been engaged in experimental and modeling investigations of the electrical turn-on behavior of high-pressure gas discharge switching. Emphasis has been on characterizing the first few nanoseconds of switch turn-on for a range of operational conditions (i.e., gas type, gas pressure, gap length, drive circuit impedance, etc.). This paper describes the modeling, signal processing, and systems analysis aspects of the investigations, which were driven by interest in pursuing the extent to which limited experimental data could be usefully augmented with available computer modeling tools and techniques. A high-fidelity 3-D model of the experimental apparatus was developed and simulations performed using a full 3-D time-domain Maxwell solver. This provided detailed electrical characterization of the experimental system that allowed for the development of transfer functions enabling the estimation of time-varying discharge gap voltage and current waveforms based on experimental D-dot probe measurements taken some distance away from the discharge gap. The steps of this process are outlined, example results shown, conclusions presented, and directions for future work suggested.

This report provides a state-of-the-art review on the role of Modeling and Simulation (M&S) in the context of the Capability Engineering Process (CEP) as defined so far by the CapDEM TD initiative. It briefly positions the preliminary guidelines proposed by the CEP within the current DND/CF acquisition process, and describes how this new process, once finalized, will efficiently implement Simulation Based Acquisition (SBA) concepts through a Collaborative Engineering Environment (CEE). The report also presents some M&S fundamentals and its use within the military acquisition process, before it describes how M&S could be used to support the main CEP activities. Some M&S tools products which could be considered for the CEP are also presented before the report concludes with suggested areas of opportunity to help refine M&S role within the CEP .

The aeronautical transport protocol AeroTP addresses the challenges of end-to-end communication in highly dynamic airborne telemetry network environment. The protocol has multiple modes: reliable, nearreliable, quasi-reliable, unreliable connection, and unreliable datagram. We present our Python implementation of reliability modes that provide end-to-end error control. The results of preliminary experiments conducted on Linux systems using AeroTP quasi-reliable mode are comparable to simulation results.

The objective of this thesis is to evaluate a modeling and simulation tool for the analysis of the Trident II D5 missile nose fairing to determine the limitations of serviceability through the extended service life of the D5 missile. The benefit of this analysis is a means to evaluate and manage the remaining nose fairing supply and serve as a baseline for future production of nose fairings. Constructed of a Sitka spruce and fiberglass laminate, the nose fairing is designed as the lifting point of the missile for submarine onloads and offloads and supports the entire weight of the missile. A computer model of the nose fairing was used to evaluate the nose fairing under tensile and compressive loading conditions to simulate the lifting evolution and closure segment impact at time of launch. Changes in the material properties of the model allow for a simulation of aging in the nose fairing to estimate the performance degradation over time, as well as exploration of the applicability of new materials to any future design of nose fairings.

This report surveys and provides lessons learned on modeling and operations analysis (OA) in Operations Enduring Freedom (OEF) and Iraqi Freedom (OIF). Operations and environmental complexities in Iraq and Afghanistan placed heavy demands on U.S. military commanders, requiring them to make critical, time-sensitive decisions with limited information. Modelers and analysts provided both direct and indirect, or reach-back, support to commanders in both theaters to help them make wellinformed decisions across the full spectrum of counterinsurgency and irregular warfare (COIN and IW) operations. Based on our analysis of both the literature and interviews with commanders and analysts, we identified four general categories that encompassed most decision support: (1) force protection; (2) logistics; (3) campaign assessment; and (4) force structure. We assess that modelers and analysts were able to successfully inform many force protection and logistics decisions, but they were less effective in supporting campaign assessment and force-structuring decisions (each category is described in greater detail below). Scope, scale, complexity, and the opacity of the operational environment were critical variables: Modeling and analysis were effective at addressing difficult but relatively concrete tactical and operational problems, but less useful in addressing complex strategic problems that required detailed analysis of the operational environment. This finding was perhaps unsurprising given the complexity of the environments and operations in both theaters, but it does help refine understanding of the ways in which modeling, simulation, and analysis might be used most effectively in IW. It also informs decisions on current and future investment in modeling and analytic capabilities. The theory and practical methods for force protection and logistics decision support are generally sound and warrant continued investment, while the theory and methods that support campaign assessme