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NASA is developing a new capsule-based, crewed vehicle that will land in the ocean, and the space agency desires to reduce the risk of injury from impact during these landings. Because landing impact occurs for each flight and the crew might need to perform egress tasks, current injury assessment reference values (IARV) were deemed insufficient. Because NASCAR occupant restraint systems are more effective than the systems used to determine the current IARVs and are similar to NASA s proposed restraint system, an analysis of NASCAR impacts was performed to develop new IARVs that may be more relevant to NASA s context of vehicle landing operations. Head IARVs associated with race car impacts were investigated by completing a detailed analysis of all of the 2002-2008 NASCAR impact data. Specific inclusion and exclusion criteria were used to select 4071 impacts from the 4015 recorder files provided (each file could contain multiple impact events). Of the 4071 accepted impacts, 274 were selected for numerical simulation using a custom NASCAR restraint system and Humanetics Hybrid-III 50th percentile numerical dummy model in LS-DYNA. Injury had occurred in 32 of the 274 selected impacts, and 27 of those injuries involved the head. A majority of the head injuries were mild concussions with or without brief loss of consciousness. The 242 non-injury impacts were randomly selected and representative of the range of crash dynamics present in the total set of 4071 impacts. Head dynamics data (head translational acceleration, translational change in velocity, rotational acceleration, rotational velocity, HIC-15, HIC-36, and the Head 3ms clip) were filtered according to SAE J211 specifications and then transformed to a log scale. The probability of head injury was estimated using a separate logistic regression analysis for each log-transformed predictor candidate. Using the log transformation constrains the estimated probability of injury to become negligible as IARVs approach zero. For the parameters head translational acceleration, head translational velocity change, head rotational acceleration, HIC-15, and HIC-36, conservative values (in the lower 95% confidence interval) that gave rise to a 5% risk of any injury occurring were estimated as 40.0 G, 7.9 m/s, 2200 rad/s2, 98.4, and 77.4 respectively. Because NASA is interested in the consequence of any particular injury on the ability of the crew to perform egress tasks, the head injuries that occurred in the NASCAR dataset were classified according to a NASA-developed scale (Classes I - III) for operationally relevant injuries, which classifies injuries on the basis of their operational significance. Additional analysis of the data was performed to determine the probability of each injury class occurring, and this was estimated using an ordered probit model. For head translational acceleration, head translational velocity change, head rotational acceleration, head rotational velocity, HIC-36, and head 3ms clip, conservative values of IARVs that produced a 5% risk of Class II injury were estimated as 50.7 G, 9.5 m/s, 2863 rad/s2, 11.0 rad/s, 30.3, and 46.4 G respectively. The results indicate that head IARVs developed from the NASCAR dataset may be useful to protect crews during landing impact.

NASA is developing a new capsule-based, crewed vehicle that will land in the ocean, and the space agency desires to reduce the risk of injury from impact during these landings. Because landing impact occurs for each flight and the crew might need to perform egress tasks, current injury assessment reference values (IARV) were deemed insufficient. Because NASCAR occupant restraint systems are more effective than the systems used to determine the current IARVs and are similar to NASA s proposed restraint system, an analysis of NASCAR impacts was performed to develop new IARVs that may be more relevant to NASA s context of vehicle landing operations. Head IARVs associated with race car impacts were investigated by completing a detailed analysis of all of the 2002-2008 NASCAR impact data. Specific inclusion and exclusion criteria were used to select 4071 impacts from the 4015 recorder files provided (each file could contain multiple impact events). Of the 4071 accepted impacts, 274 were selected for numerical simulation using a custom NASCAR restraint system and Humanetics Hybrid-III 50th percentile numerical dummy model in LS-DYNA. Injury had occurred in 32 of the 274 selected impacts, and 27 of those injuries involved the head. A majority of the head injuries were mild concussions with or without brief loss of consciousness. The 242 non-injury impacts were randomly selected and representative of the range of crash dynamics present in the total set of 4071 impacts. Head dynamics data (head translational acceleration, translational change in velocity, rotational acceleration, rotational velocity, HIC-15, HIC-36, and the Head 3ms clip) were filtered according to SAE J211 specifications and then transformed to a log scale. The probability of head injury was estimated using a separate logistic regression analysis for each log-transformed predictor candidate. Using the log transformation constrains the estimated probability of injury to become negligible as IARVs approach zero. For the parameters head translational acceleration, head translational velocity change, head rotational acceleration, HIC-15, and HIC-36, conservative values (in the lower 95% confidence interval) that gave rise to a 5% risk of any injury occurring were estimated as 40.0 G, 7.9 m/s, 2200 rad/s2, 98.4, and 77.4 respectively. Because NASA is interested in the consequence of any particular injury on the ability of the crew to perform egress tasks, the head injuries that occurred in the NASCAR dataset were classified according to a NASA-developed scale (Classes I - III) for operationally relevant injuries, which classifies injuries on the basis of their operational significance. Additional analysis of the data was performed to determine the probability of each injury class occurring, and this was estimated using an ordered probit model. For head translational acceleration, head translational velocity change, head rotational acceleration, head rotational velocity, HIC-36, and head 3ms clip, conservative values of IARVs that produced a 5% risk of Class II injury were estimated as 50.7 G, 9.5 m/s, 2863 rad/s2, 11.0 rad/s, 30.3, and 46.4 G respectively. The results indicate that head IARVs developed from the NASCAR dataset may be useful to protect crews during landing impact.

Dwarf Mistletoe Impact Modeling System, User Guide and Reference Manual Nonspatial Model - 2005 Update [The spatial version of the Dwarf Mistletoe Model is not supported by USDA Forest Service Forest Heath Technology Enterprise Team; therefore, information relevant only to the spatial model has been removed from this document.] Original document written by Frank G. Hawksworth, Julie C. Williams-Cipriani, Bov B. Eav, Brian W. Geils, Ralph R. Johnson, Michael A. Marsden, Jerome S. Beatty, Gregory D. Shubert, and Donald C. E. Robinson

An On-Line Modeling System (OLMS) which should be particularly useful to the biomedical community is described which utilizes a process called "overlaying" to simplify loading and executing programs. OLMS has been constructed and implemented as an interpreter; that is, a program that translates and then executes each source statement in sequence where these two operations follow each other in close time proximity. It has been written so that it can be run under the IBM S/360 and the PDP-10 operating systems, but has been implemented only on the PDP-10. OLMS operates from a command language that is executed interpretively through a set of closed subroutines. The user may run a job, save data, get data, and display data. While his program is running, he can access the whole memory. This report consists of a description of OLMS and programmer's reference manuals for both the OLMS graphical system and OLMS. (JY)

An On-Line Modeling System (OLMS) which should be particularly useful to the biomedical community is described which utilizes a process called "overlaying" to simplify loading and executing programs. OLMS has been constructed and implemented as an interpreter; that is, a program that translates and then executes each source statement in sequence where these two operations follow each other in close time proximity. It has been written so that it can be run under the IBM S/360 and the PDP-10 operating systems, but has been implemented only on the PDP-10. OLMS operates from a command language that is executed interpretively through a set of closed subroutines. The user may run a job, save data, get data, and display data. While his program is running, he can access the whole memory. This report consists of a description of OLMS and programmer's reference manuals for both the OLMS graphical system and OLMS. (JY)

The C2RM provides a framework for the evolution of a coordinated and detailed definition of a command and control (C2) discipline. The C2RM embodies an integrated multidisciplinary approach. It is intended to be complete and self-consistent for the main levels of abstractions encountered in models, simulations, operational applications, functional descriptions, paradigms and metaphors of C2. The scope of the C2RM embraces C2 using all key physical and logical interactions associated with C2 systems. It is concerned with interactions, involving not only communications (e.g., radios), but transportations (e.g., vehicles), identifications (e.g., sensors), and inflictions (e.g., weapons), which take place between resources of the same, friendly, hostile or neutral C2 units. High levels of abstractions of user requirements for C2 across the broad spectrum of military and civil domains have led to the development of the C2RM. It applies to all phases of system acquisition from the laboratory to the field and from conceptualization to realization. The C2RM is based upon generic and analog extensions to the International Standards Organization (ISO) open system interconnection (OSI) reference model (RM) which go far beyond the scope of the ISO OSI RM. The major theme, however, of layering services is preserved to facilitate understanding, reuse of design, implementation, and interoperability to the maximum degree possible with available C2 technology.

As an emergent infectious disease outbreak unfolds, public health response is reliant on information on key epidemiological quantities, such as transmission potential and serial interval. Increasingly, transmission models fit to incidence data are used to estimate these parameters and guide policy. Some widely-used modeling practices lead to potentially large errors in parameter estimates and, consequently, errors in model-based forecasts. Even more worryingly, in such situations, confidence in parameter estimates and forecasts can itself be far over-estimated, leading to the potential for large errors that mask their own presence. Fortunately, straightforward and computationally inexpensive alternatives exist that avoid these problems. Here, we first use a simulation study to demonstrate potential pitfalls of the standard practice of fitting deterministic models to cumulative incidence data. Next, we demonstrate an alternative based on stochastic models fit to raw data from an early phase of 2014 West Africa Ebola Virus Disease outbreak. We show not only that bias is thereby reduced, but that uncertainty in estimates and forecasts is better quantified and that, critically, lack of model fit is more readily diagnosed. We conclude with a short list of principles to guide the modeling response to future infectious disease outbreaks.

The effect of an arbitrary change of frame on the structure of turbulence models is examined from a fundamental theoretical standpoint. It is proven, as a rigorous consequence of the Navier-Stokes equations, that turbulence models must be form invariant under arbitrary translational accelerations of the reference frame and should only be affected by rotations through the intrinsic mean vorticity. A direct application of the invariance property along with the Taylor-Proudman Theorem, material frame-indifference in the limit of two-dimensional turbulence and Rapid Distortion Theory is shown to yield powerful constraints on the allowable form of turbulence models. Most of the commonly used turbulence models are demonstrated to be in serious violation of these constraints and consequently are inconsistent with the Navier-Stokes equations in non-inertial frames. Alternative models with improved non-inertial properties are developed and some simple applications to rotating turbulent flows are considered.

This report defines basic reference frames and transformations which are offered as standards in Air-to-Air Gunnery Assessment Modeling (ATAGAM). Adoption would make this report a documentztion of these elements of about 12 known USAF ATAGAM models while minimizing their bookkeeping requirements and increasing their general comprehension. The basics are applicable to other conventional weapon delivery methodologies i.e., for missiles, rockets, bombs, cannisters, etc. (Author)

This report defines basic reference frames and transformations which are offered as standards in Air-to-Air Gunnery Assessment Modeling (ATAGAM). Adoption would make this report a documentztion of these elements of about 12 known USAF ATAGAM models while minimizing their bookkeeping requirements and increasing their general comprehension. The basics are applicable to other conventional weapon delivery methodologies i.e., for missiles, rockets, bombs, cannisters, etc. (Author)

We describe low-lying collective excitations of atomic nuclei with the multi-reference covariant density functional theory, and combine them with coupled-channels calculations for heavy-ion fusion reactions at energies around the Coulomb barrier. To this end, we use the calculated transition strengths among several collective states as inputs to the coupled-channels calculations. This approach provides a natural way to describe anharmonic multi-phonon excitations as well as a deviation of rotational excitations from a simple rigid rotor. We apply this method to subbarrier fusion reactions of $^{58}$Ni+$^{58}$Ni, $^{58}$Ni+$^{60}$Ni and $^{40}$Ca+$^{58}$Ni systems. We find that the effect of anharmonicity tends to smear the fusion barrier distributions, better reproducing the experimental data compared to the calculations in the harmonic oscillator limit.

Lines were drawn on models with greasepencil for reference in modeling human anatomy within a 3D modeling environment.

The Advanced Weapons Concepts Branch, Army Research Laboratory (ARL), was asked to assess and evaluate the predicted cross-country performance of the current DEMO III Experimental Unmanned Ground Vehicle (XUV) chassis design using the NATO Reference Mobility Model (NRMM) by the Program Manager of the Department of Defense sponsored DEMO III XUV Program. The XUV modeled approximately 2,500 lb that will be able to traverse cross-country terrain at 20 mph. The XUV is designed to be driven by an autonomous mobility package, but the NRMM does not support autonomous mobility; so, for the purposes of this study, the chassis was modeled as a manned vehicle. Currently, the XUV is in the final chassis and suspension development phase by the systems integrator, Robotic Systems Technology, Inc. The NRMM is a computer-based simulation tool that can predict a vehicle's steady-state operating capability (effective maximum speed) over specified terrain. The NRMM can perform on-road and cross-country prediction of a vehicle's effective maximum speed. The NRMM is a matured technology that was developed and proven by the Waterways Experiment Station (WES) and the Tank-automotive and Armaments Command (TACOM) over several decades. The NRMM has been revised and updated throughout the years; the current version used to perform this analysis is version 2, also known as NRMM II. ARL was also asked to compare the predicted performance of the XUV chassis against the high-mobility, multipurpose, wheeled vehicle (HMMWV) using NRMM II. This report details the NRMM II analysis and assessment of the DEMO III XUV and WES HMMWV.

This manual is a companion to an earlier one, "Reinforcing Productive Classroom Behavior," that dealt with the use of reinforcement procedures by school personnel as a means for shaping constructive behavior in children. The present pamphlet continues to focus on the behavior influence process, but its topic is modeling and role-playing as applied to classroom settings. Their educational implications have stimulated both general excitement and the development of specific techniques that are relevant to pressing problems in the classroom. Modeling is a process by which responses are acquired through observing the behavior of someone else (the model). When people role-play they enact social roles other than their own. This manual was written to help school personnel use modeling and role-playing in productive ways. Its intended readers include teachers, teachers in training, counselors, and administrators. Its development was guided by both educators and research workers. Although more basic research in modeling is needed, it is clear that it can have powerful impacts and that these can be either for good or ill. This pamphlet describes how modeling can be used to achieve desirable goals. It summarizes the literature on modeling and discusses how teachers and other personnel in the school can use modeling for the benefit of students. (Author/JM)

Modeling Tips PT5 - The Value Of Reference

Modeling Tips PT5 - The Value Of Reference

The robustness of model reference adaptive schemes with respect to unmodeled parasitics is analyzed. Bounds on parameter and state errors are established for identifiers and adaptive observers. In the case of adaptive control, algorithms are modified to guarantee boundedness. Decentralized adaptive control schemes guaranteeing the stability of a class of large-scale systems are proposed. This thesis is divided into six sections. Different characterizations are given for the model-plant mismatch in Sections 2 to 5 and 6. The characterization in Sections 2 to 5 assumes a separation of time scales between the modeled and unmodeled phenomena. The order of the model is equal to the order of the slow part of the unknown plant and the model-plant mismatch is due to the fast part of the plant. In most applications the slow part consists of dominant modes, while the neglected fast modes are considered as parasitics. The approach is asymptotic. In Section 6 the model-plant mismatch is characterized by neglected interconnections between different subsystems. Adaptive schemes are first designed for the decoupled subsystems and then applied to the overall system with the interconnections.

The purpose of this paper is to present a multi-level operational C2 holonic reference architecture that is applicable to Navy maritime headquarters (MHQ) with maritime operations center (MOC) for assessing, planning and executing multiple missions and tasks across a range of military operations. The control architecture consists of three levels: strategic level control (SLC), operational level control (OLC) and tactical level control (TLC). In addition to coordination within each level, two specific coordination layers are identified at the SLC-OLC and the OLC-TLC interfaces. The SLC-OLC interface layer resolves evaluation issues associate with selecting DIME (diplomatic, information, military and economic) actions based on national priorities, while the OLCTLC interface layer is used to resolve mission monitoring/planning issues associated with deciding on the courses of action based on outcomes of asset-task allocation at the tactical level. We employ semi-Markov decision process (SMDP) approach to decide on missions to be executed and their time sequence at the SLC-OLC layer (coordination of future plans), while a distributed SMDP approach to an action-goal attainment (AGA) graph for addressing the mission monitoring/ planning issues related to task sequencing and asset allocation at the OLC-TLC layer (coordination of future operations and current operations).

The adoption Enterprise Resource Planning (ERPs) by small and medium-sized businesses may not possible its cost. At same time, whenever adapt ERP specific needs company, user becomes dependent developers due to the lack access and knowledge respective code. Free and open source software can promote advantages companies, however, for their adoption, it is necessary to develop techniques tools facilitate implementation and maintenance code. This article highlights the importance of defining modeling architectures and reference models for development and maintenance open source ERPs, especially the ERP5 project.

The effect of an arbitrary change of frame on the structure of turbulence models is examined from a fundamental theoretical standpoint. It is proven, as a rigorous consequence of the Navier Stokes equations, that turbulence models must be form invariant under arbitrary translational accelerations of the reference frame and should only be affected by rotations through the intrinsic mean vorticity. A direct application of this invariance property along with the Taylor-Proudman Theorem, material frame indifference in the limit of two dimensional turbulence and Rapid Distortion Theory is shown to yield powerful constraints on the allowable form of turbulence models. Most of the commonly used turbulence models are demonstrated to be in serious violation of these constraints and consequently are inconsistent with the Navier Stokes equations in noninertial frames. Alternative models with improved noninertial properties are developed and some simple applications to rotating turbulent flows are considered. Keywords: Turbulence modeling; Rotating flows; Computational fluid mechanics.

The Emissions and Dispersion Modeling System (EDMS) was developed in the mid-l980s as a complex source microcomputer model to assess the air quality impacts of proposed airport development project In response to the growing needs of the air quality analysis community and changes in regulations (Conformity requirements from the Clean Air Act Amendment of 1990) the Federal Aviation Administration (FAA) in cooperation with the United States Air Force (USAF) has re-engineered and enhanced EDMS. EDMS Version 3.0 was built under the guidance of a government and industry advisory board composed of experts from the scientific, environmental policy, and analysis fields. It features the latest aircraft engine emission factors from the International Civil Aviation Organization (ICAO) Engine Exhaust Emissions Data Bank, vehicle emission factors from the Environmental Protection Agency's (EPA) MOBlLE5a, EPA-validated dispersion models, and improved performance. The analyst can more effectively determine emission levels and concentrations generated by the typical airport/air base sources (i.e. aircraft, ground support equipment) as well as the airport/air base associated emissions contributors such as motor vehicles and power plants. This Reference Manual is intended to provide detailed information on the functionality of the model and acts as an extension and elaboration of the on-line help. The section on References provides an extensive listing of documents that may be of further assistance to the analyst in the use of EDMS and the preparation of an Environmental Impact Statement (ElS).

The Emissions and Dispersion Modeling System (EDMS) was developed in the mid-l980s as a complex source microcomputer model to assess the air quality impacts of proposed airport development project In response to the growing needs of the air quality analysis community and changes in regulations (Conformity requirements from the Clean Air Act Amendment of 1990) the Federal Aviation Administration (FAA) in cooperation with the United States Air Force (USAF) has re-engineered and enhanced EDMS. EDMS Version 3.0 was built under the guidance of a government and industry advisory board composed of experts from the scientific, environmental policy, and analysis fields. It features the latest aircraft engine emission factors from the International Civil Aviation Organization (ICAO) Engine Exhaust Emissions Data Bank, vehicle emission factors from the Environmental Protection Agency's (EPA) MOBlLE5a, EPA-validated dispersion models, and improved performance. The analyst can more effectively determine emission levels and concentrations generated by the typical airport/air base sources (i.e. aircraft, ground support equipment) as well as the airport/air base associated emissions contributors such as motor vehicles and power plants. This Reference Manual is intended to provide detailed information on the functionality of the model and acts as an extension and elaboration of the on-line help. The section on References provides an extensive listing of documents that may be of further assistance to the analyst in the use of EDMS and the preparation of an Environmental Impact Statement (ElS).

The Emissions and Dispersion Modeling System (EDMS) was developed in the mid-l980s as a complex source microcomputer model to assess the air quality impacts of proposed airport development project In response to the growing needs of the air quality analysis community and changes in regulations (Conformity requirements from the Clean Air Act Amendment of 1990) the Federal Aviation Administration (FAA) in cooperation with the United States Air Force (USAF) has re-engineered and enhanced EDMS. EDMS Version 3.0 was built under the guidance of a government and industry advisory board composed of experts from the scientific, environmental policy, and analysis fields. It features the latest aircraft engine emission factors from the International Civil Aviation Organization (ICAO) Engine Exhaust Emissions Data Bank, vehicle emission factors from the Environmental Protection Agency's (EPA) MOBlLE5a, EPA-validated dispersion models, and improved performance. The analyst can more effectively determine emission levels and concentrations generated by the typical airport/air base sources (i.e. aircraft, ground support equipment) as well as the airport/air base associated emissions contributors such as motor vehicles and power plants. This Reference Manual is intended to provide detailed information on the functionality of the model and acts as an extension and elaboration of the on-line help. The section on References provides an extensive listing of documents that may be of further assistance to the analyst in the use of EDMS and the preparation of an Environmental Impact Statement (ElS).

Journal of Research of the National Institute of Standards and Technology

Journal of Research of the National Institute of Standards and Technology

In the present study, performance of data-mining methods in modeling and estimating reference crop evapotranspiration (ET o ) is investigated. To this end, different machine learning, including Artificial Neural Network (ANN), M5 tree, Multivariate Adaptive Regression Splines (MARS), Least Square Support Vector Machine (LS-SVM), and Random Forest (RF) are employed by considering different criteria including impacts of climate (eight synoptic stations in humid and dry climates), accuracy, uncertainty and computation time. Furthermore, to show the application of data-mining methods, their results are compared with some empirical equations, that indicated the superiority of data- mining methods. In the humid climate, it was demonstrated that M5 tree model is the best if only accuracy criterion is considered, and MARS is a better data-mining method by considering accuracy, uncertainty, and computation time criteria. While in the dry climate, the ANN has better results by considering accuracy and all other criteria. In the final step, for a comprehensive investigation of data-mining ability in ET o  modeling, all data in humid and dry climates are combined. Results showed the highest accuracy by MARS and ANN models.

In the present study, performance of data-mining methods in modeling and estimating reference crop evapotranspiration (ET o ) is investigated. To this end, different machine learning, including Artificial Neural Network (ANN), M5 tree, Multivariate Adaptive Regression Splines (MARS), Least Square Support Vector Machine (LS-SVM), and Random Forest (RF) are employed by considering different criteria including impacts of climate (eight synoptic stations in humid and dry climates), accuracy, uncertainty and computation time. Furthermore, to show the application of data-mining methods, their results are compared with some empirical equations, that indicated the superiority of data- mining methods. In the humid climate, it was demonstrated that M5 tree model is the best if only accuracy criterion is considered, and MARS is a better data-mining method by considering accuracy, uncertainty, and computation time criteria. While in the dry climate, the ANN has better results by considering accuracy and all other criteria. In the final step, for a comprehensive investigation of data-mining ability in ET o  modeling, all data in humid and dry climates are combined. Results showed the highest accuracy by MARS and ANN models.

Includes bibliographical references (p. 537) and index

Includes bibliographical references (p. 537) and index

Includes bibliographical references (p. 537) and index

Includes bibliographical references (p. 537) and index

Includes bibliographical references (p. 537) and index