Design and analysis of sustainable computer mouse using design for disassembly methodology

NASA Astrophysics Data System (ADS)

Roni Sahroni, Taufik; Fitri Sukarman, Ahmad; Agung Mahardini, Karunia

2017-12-01

This paper presents the design and analysis of computer mouse using Design for Disassembly methodology. Basically, the existing computer mouse model consist a number of unnecessary part that cause the assembly and disassembly time in production. The objective of this project is to design a new computer mouse based on Design for Disassembly (DFD) methodology. The main methodology of this paper was proposed from sketch generation, concept selection, and concept scoring. Based on the design screening, design concept B was selected for further analysis. New design of computer mouse is proposed using fastening system. Furthermore, three materials of ABS, Polycarbonate, and PE high density were prepared to determine the environmental impact category. Sustainable analysis was conducted using software SolidWorks. As a result, PE High Density gives the lowers amount in the environmental category with great maximum stress value.

Locomotive cab design development. Volume 1 : analysis of locomotive cab environment & development of cab design alternatives

DOT National Transportation Integrated Search

1976-10-01

This report presents an analysis of the line haul freight : engineer's working and living environment, the resultant locomotive : cab design and design alternatives. The analysis is based on a : delineation of functional requirements found in current...

Design Optimization Method for Composite Components Based on Moment Reliability-Sensitivity Criteria

NASA Astrophysics Data System (ADS)

Sun, Zhigang; Wang, Changxi; Niu, Xuming; Song, Yingdong

2017-08-01

In this paper, a Reliability-Sensitivity Based Design Optimization (RSBDO) methodology for the design of the ceramic matrix composites (CMCs) components has been proposed. A practical and efficient method for reliability analysis and sensitivity analysis of complex components with arbitrary distribution parameters are investigated by using the perturbation method, the respond surface method, the Edgeworth series and the sensitivity analysis approach. The RSBDO methodology is then established by incorporating sensitivity calculation model into RBDO methodology. Finally, the proposed RSBDO methodology is applied to the design of the CMCs components. By comparing with Monte Carlo simulation, the numerical results demonstrate that the proposed methodology provides an accurate, convergent and computationally efficient method for reliability-analysis based finite element modeling engineering practice.

Analysis of Combined Data from Heterogeneous Study Designs: A Methodological Proposal from the Patient Navigation Research program

PubMed Central

Roetzheim, Richard G.; Freund, Karen M.; Corle, Don K.; Murray, David M.; Snyder, Frederick R.; Kronman, Andrea C.; Jean-Pierre, Pascal; Raich, Peter C.; Holden, Alan E. C.; Darnell, Julie S.; Warren-Mears, Victoria; Patierno, Steven; Design, PNRP; Committee, Analysis

2013-01-01

Background The Patient Navigation Research Program (PNRP) is a cooperative effort of nine research projects, each employing its own unique study design. To evaluate projects such as PNRP, it is desirable to perform a pooled analysis to increase power relative to the individual projects. There is no agreed upon prospective methodology, however, for analyzing combined data arising from different study designs. Expert opinions were thus solicited from members of the PNRP Design and Analysis Committee Purpose To review possible methodologies for analyzing combined data arising from heterogeneous study designs. Methods The Design and Analysis Committee critically reviewed the pros and cons of five potential methods for analyzing combined PNRP project data. Conclusions were based on simple consensus. The five approaches reviewed included: 1) Analyzing and reporting each project separately, 2) Combining data from all projects and performing an individual-level analysis, 3) Pooling data from projects having similar study designs, 4) Analyzing pooled data using a prospective meta analytic technique, 5) Analyzing pooled data utilizing a novel simulated group randomized design. Results Methodologies varied in their ability to incorporate data from all PNRP projects, to appropriately account for differing study designs, and in their impact from differing project sample sizes. Limitations The conclusions reached were based on expert opinion and not derived from actual analyses performed. Conclusions The ability to analyze pooled data arising from differing study designs may provide pertinent information to inform programmatic, budgetary, and policy perspectives. Multi-site community-based research may not lend itself well to the more stringent explanatory and pragmatic standards of a randomized controlled trial design. Given our growing interest in community-based population research, the challenges inherent in the analysis of heterogeneous study design are likely to become more salient. Discussion of the analytic issues faced by the PNRP and the methodological approaches we considered may be of value to other prospective community-based research programs. PMID:22273587

Analysis of combined data from heterogeneous study designs: an applied example from the patient navigation research program.

PubMed

Roetzheim, Richard G; Freund, Karen M; Corle, Don K; Murray, David M; Snyder, Frederick R; Kronman, Andrea C; Jean-Pierre, Pascal; Raich, Peter C; Holden, Alan Ec; Darnell, Julie S; Warren-Mears, Victoria; Patierno, Steven

2012-04-01

The Patient Navigation Research Program (PNRP) is a cooperative effort of nine research projects, with similar clinical criteria but with different study designs. To evaluate projects such as PNRP, it is desirable to perform a pooled analysis to increase power relative to the individual projects. There is no agreed-upon prospective methodology, however, for analyzing combined data arising from different study designs. Expert opinions were thus solicited from the members of the PNRP Design and Analysis Committee. To review possible methodologies for analyzing combined data arising from heterogeneous study designs. The Design and Analysis Committee critically reviewed the pros and cons of five potential methods for analyzing combined PNRP project data. The conclusions were based on simple consensus. The five approaches reviewed included the following: (1) analyzing and reporting each project separately, (2) combining data from all projects and performing an individual-level analysis, (3) pooling data from projects having similar study designs, (4) analyzing pooled data using a prospective meta-analytic technique, and (5) analyzing pooled data utilizing a novel simulated group-randomized design. Methodologies varied in their ability to incorporate data from all PNRP projects, to appropriately account for differing study designs, and to accommodate differing project sample sizes. The conclusions reached were based on expert opinion and not derived from actual analyses performed. The ability to analyze pooled data arising from differing study designs may provide pertinent information to inform programmatic, budgetary, and policy perspectives. Multisite community-based research may not lend itself well to the more stringent explanatory and pragmatic standards of a randomized controlled trial design. Given our growing interest in community-based population research, the challenges inherent in the analysis of heterogeneous study design are likely to become more salient. Discussion of the analytic issues faced by the PNRP and the methodological approaches we considered may be of value to other prospective community-based research programs.

Design and Analysis of Subscale and Full-Scale Buckling-Critical Cylinders for Launch Vehicle Technology Development

NASA Technical Reports Server (NTRS)

Hilburger, Mark W.; Lovejoy, Andrew E.; Thornburgh, Robert P.; Rankin, Charles

2012-01-01

NASA s Shell Buckling Knockdown Factor (SBKF) project has the goal of developing new analysis-based shell buckling design factors (knockdown factors) and design and analysis technologies for launch vehicle structures. Preliminary design studies indicate that implementation of these new knockdown factors can enable significant reductions in mass and mass-growth in these vehicles. However, in order to validate any new analysis-based design data or methods, a series of carefully designed and executed structural tests are required at both the subscale and full-scale levels. This paper describes the design and analysis of three different orthogrid-stiffeNed metallic cylindrical-shell test articles. Two of the test articles are 8-ft-diameter, 6-ft-long test articles, and one test article is a 27.5-ft-diameter, 20-ft-long Space Shuttle External Tank-derived test article.

Effects of Instructional Design with Mental Model Analysis on Learning.

ERIC Educational Resources Information Center

Hong, Eunsook

This paper presents a model for systematic instructional design that includes mental model analysis together with the procedures used in developing computer-based instructional materials in the area of statistical hypothesis testing. The instructional design model is based on the premise that the objective for learning is to achieve expert-like…

Comparative analysis of design codes for timber bridges in Canada, the United States, and Europe

Treesearch

James Wacker; James (Scott) Groenier

2010-01-01

The United States recently completed its transition from the allowable stress design code to the load and resistance factor design (LRFD) reliability-based code for the design of most highway bridges. For an international perspective on the LRFD-based bridge codes, a comparative analysis is presented: a study addressed national codes of the United States, Canada, and...

Analysis and Design of Power Factor Pre-Regulator Based on a Symmetrical Charge Pump Circuit Applied to Electronic Ballast

NASA Astrophysics Data System (ADS)

Lazcano Olea, Miguel; Ramos Astudillo, Reynaldo; Sanhueza Robles, René; Rodriguez Rubke, Leopoldo; Ruiz-Caballero, Domingo Antonio

This paper presents the analysis and design of a power factor pre-regulator based on a symmetrical charge pump circuit applied to electronic ballast. The operation stages of the circuit are analyzed and its main design equations are obtained. Simulation and experimental results are presented in order to show the design methodology feasibility.

A non-stationary cost-benefit analysis approach for extreme flood estimation to explore the nexus of 'Risk, Cost and Non-stationarity'

NASA Astrophysics Data System (ADS)

Qi, Wei

2017-11-01

Cost-benefit analysis is commonly used for engineering planning and design problems in practice. However, previous cost-benefit based design flood estimation is based on stationary assumption. This study develops a non-stationary cost-benefit based design flood estimation approach. This approach integrates a non-stationary probability distribution function into cost-benefit analysis, and influence of non-stationarity on expected total cost (including flood damage and construction costs) and design flood estimation can be quantified. To facilitate design flood selections, a 'Risk-Cost' analysis approach is developed, which reveals the nexus of extreme flood risk, expected total cost and design life periods. Two basins, with 54-year and 104-year flood data respectively, are utilized to illustrate the application. It is found that the developed approach can effectively reveal changes of expected total cost and extreme floods in different design life periods. In addition, trade-offs are found between extreme flood risk and expected total cost, which reflect increases in cost to mitigate risk. Comparing with stationary approaches which generate only one expected total cost curve and therefore only one design flood estimation, the proposed new approach generate design flood estimation intervals and the 'Risk-Cost' approach selects a design flood value from the intervals based on the trade-offs between extreme flood risk and expected total cost. This study provides a new approach towards a better understanding of the influence of non-stationarity on expected total cost and design floods, and could be beneficial to cost-benefit based non-stationary design flood estimation across the world.

DCL System Research Using Advanced Approaches for Land-based or Ship-based Real-Time Recognition and Localization of Marine Mammals

DTIC Science & Technology

2012-09-30

recognition. Algorithm design and statistical analysis and feature analysis. Post -Doctoral Associate, Cornell University, Bioacoustics Research...short. The HPC-ADA was designed based on fielded systems [1-4, 6] that offer a variety of desirable attributes, specifically dynamic resource...The software package was designed to utilize parallel and distributed processing for running recognition and other advanced algorithms. DeLMA

Developing a Problem-Based Course Based on Needs Analysis to Enhance English Reading Ability of Thai Undergraduate Students

ERIC Educational Resources Information Center

Bosuwon, Takwa; Woodrow, Lindy

2009-01-01

This paper reports on a needs analysis underlying a proposed business English reading course using a problem-based learning approach designed to enhance English reading abilities of Thai undergraduate students. As part of a work in progress, the needs analysis survey was done prior to the course design with the major stakeholders in business and…

Creating A Data Base For Design Of An Impeller

NASA Technical Reports Server (NTRS)

Prueger, George H.; Chen, Wei-Chung

1993-01-01

Report describes use of Taguchi method of parametric design to create data base facilitating optimization of design of impeller in centrifugal pump. Data base enables systematic design analysis covering all significant design parameters. Reduces time and cost of parametric optimization of design: for particular impeller considered, one can cover 4,374 designs by computational simulations of performance for only 18 cases.

Exploration of a Capability-Focused Aerospace System of Systems Architecture Alternative with Bilayer Design Space, Based on RST-SOM Algorithmic Methods

PubMed Central

Li, Zhifei; Qin, Dongliang

2014-01-01

In defense related programs, the use of capability-based analysis, design, and acquisition has been significant. In order to confront one of the most challenging features of a huge design space in capability based analysis (CBA), a literature review of design space exploration was first examined. Then, in the process of an aerospace system of systems design space exploration, a bilayer mapping method was put forward, based on the existing experimental and operating data. Finally, the feasibility of the foregoing approach was demonstrated with an illustrative example. With the data mining RST (rough sets theory) and SOM (self-organized mapping) techniques, the alternative to the aerospace system of systems architecture was mapping from P-space (performance space) to C-space (configuration space), and then from C-space to D-space (design space), respectively. Ultimately, the performance space was mapped to the design space, which completed the exploration and preliminary reduction of the entire design space. This method provides a computational analysis and implementation scheme for large-scale simulation. PMID:24790572

Exploration of a capability-focused aerospace system of systems architecture alternative with bilayer design space, based on RST-SOM algorithmic methods.

PubMed

Li, Zhifei; Qin, Dongliang; Yang, Feng

2014-01-01

In defense related programs, the use of capability-based analysis, design, and acquisition has been significant. In order to confront one of the most challenging features of a huge design space in capability based analysis (CBA), a literature review of design space exploration was first examined. Then, in the process of an aerospace system of systems design space exploration, a bilayer mapping method was put forward, based on the existing experimental and operating data. Finally, the feasibility of the foregoing approach was demonstrated with an illustrative example. With the data mining RST (rough sets theory) and SOM (self-organized mapping) techniques, the alternative to the aerospace system of systems architecture was mapping from P-space (performance space) to C-space (configuration space), and then from C-space to D-space (design space), respectively. Ultimately, the performance space was mapped to the design space, which completed the exploration and preliminary reduction of the entire design space. This method provides a computational analysis and implementation scheme for large-scale simulation.

Three Dialogs: A Framework for the Analysis and Assessment of Twenty-First-Century Literacy Practices, and Its Use in the Context of Game Design within "Gamestar Mechanic"

ERIC Educational Resources Information Center

Games, Ivan Alex

2008-01-01

This article discusses a framework for the analysis and assessment of twenty-first-century language and literacy practices in game and design-based contexts. It presents the framework in the context of game design within "Gamestar Mechanic", an innovative game-based learning environment where children learn the Discourse of game design. It…

An expert system for integrated structural analysis and design optimization for aerospace structures

NASA Technical Reports Server (NTRS)

1992-01-01

The results of a research study on the development of an expert system for integrated structural analysis and design optimization is presented. An Object Representation Language (ORL) was developed first in conjunction with a rule-based system. This ORL/AI shell was then used to develop expert systems to provide assistance with a variety of structural analysis and design optimization tasks, in conjunction with procedural modules for finite element structural analysis and design optimization. The main goal of the research study was to provide expertise, judgment, and reasoning capabilities in the aerospace structural design process. This will allow engineers performing structural analysis and design, even without extensive experience in the field, to develop error-free, efficient and reliable structural designs very rapidly and cost-effectively. This would not only improve the productivity of design engineers and analysts, but also significantly reduce time to completion of structural design. An extensive literature survey in the field of structural analysis, design optimization, artificial intelligence, and database management systems and their application to the structural design process was first performed. A feasibility study was then performed, and the architecture and the conceptual design for the integrated 'intelligent' structural analysis and design optimization software was then developed. An Object Representation Language (ORL), in conjunction with a rule-based system, was then developed using C++. Such an approach would improve the expressiveness for knowledge representation (especially for structural analysis and design applications), provide ability to build very large and practical expert systems, and provide an efficient way for storing knowledge. Functional specifications for the expert systems were then developed. The ORL/AI shell was then used to develop a variety of modules of expert systems for a variety of modeling, finite element analysis, and design optimization tasks in the integrated aerospace structural design process. These expert systems were developed to work in conjunction with procedural finite element structural analysis and design optimization modules (developed in-house at SAT, Inc.). The complete software, AutoDesign, so developed, can be used for integrated 'intelligent' structural analysis and design optimization. The software was beta-tested at a variety of companies, used by a range of engineers with different levels of background and expertise. Based on the feedback obtained by such users, conclusions were developed and are provided.

An expert system for integrated structural analysis and design optimization for aerospace structures

NASA Astrophysics Data System (ADS)

1992-04-01

The results of a research study on the development of an expert system for integrated structural analysis and design optimization is presented. An Object Representation Language (ORL) was developed first in conjunction with a rule-based system. This ORL/AI shell was then used to develop expert systems to provide assistance with a variety of structural analysis and design optimization tasks, in conjunction with procedural modules for finite element structural analysis and design optimization. The main goal of the research study was to provide expertise, judgment, and reasoning capabilities in the aerospace structural design process. This will allow engineers performing structural analysis and design, even without extensive experience in the field, to develop error-free, efficient and reliable structural designs very rapidly and cost-effectively. This would not only improve the productivity of design engineers and analysts, but also significantly reduce time to completion of structural design. An extensive literature survey in the field of structural analysis, design optimization, artificial intelligence, and database management systems and their application to the structural design process was first performed. A feasibility study was then performed, and the architecture and the conceptual design for the integrated 'intelligent' structural analysis and design optimization software was then developed. An Object Representation Language (ORL), in conjunction with a rule-based system, was then developed using C++. Such an approach would improve the expressiveness for knowledge representation (especially for structural analysis and design applications), provide ability to build very large and practical expert systems, and provide an efficient way for storing knowledge. Functional specifications for the expert systems were then developed. The ORL/AI shell was then used to develop a variety of modules of expert systems for a variety of modeling, finite element analysis, and design optimization tasks in the integrated aerospace structural design process. These expert systems were developed to work in conjunction with procedural finite element structural analysis and design optimization modules (developed in-house at SAT, Inc.). The complete software, AutoDesign, so developed, can be used for integrated 'intelligent' structural analysis and design optimization. The software was beta-tested at a variety of companies, used by a range of engineers with different levels of background and expertise. Based on the feedback obtained by such users, conclusions were developed and are provided.

A new rational-based optimal design strategy of ship structure based on multi-level analysis and super-element modeling method

NASA Astrophysics Data System (ADS)

Sun, Li; Wang, Deyu

2011-09-01

A new multi-level analysis method of introducing the super-element modeling method, derived from the multi-level analysis method first proposed by O. F. Hughes, has been proposed in this paper to solve the problem of high time cost in adopting a rational-based optimal design method for ship structural design. Furthermore, the method was verified by its effective application in optimization of the mid-ship section of a container ship. A full 3-D FEM model of a ship, suffering static and quasi-static loads, was used as the analyzing object for evaluating the structural performance of the mid-ship module, including static strength and buckling performance. Research results reveal that this new method could substantially reduce the computational cost of the rational-based optimization problem without decreasing its accuracy, which increases the feasibility and economic efficiency of using a rational-based optimal design method in ship structural design.

Ergonomic study and static analysis for new design of electric scooter

NASA Astrophysics Data System (ADS)

Fadzly, M. K.; Munirah, Anis; Shayfull, Z.; Saad, Mohd Sazli

2017-09-01

The purposes of this project are to design and diversify the function of a battery powered scooter frame which is more practical for the human factor in ergonomic and optimum design. The new design is based on ideas which are studied from existing scooter frame, United States Patent design and European States International Patent design. The final idea of concept design for scooter frame is based on concept chosen from the best characteristics and it is divided into three main difference ideas and the matrix evaluation method is applied. Analysis that applies to frame design, arm, rim and drive train component is based on Cosmos Express program. As a conclusion, the design that is produce are able to carry the maximum also has more practical features in ergonomic view.

Design-to-cost

NASA Technical Reports Server (NTRS)

Bradley, F. E.

1974-01-01

Attempts made to design to costs equipment, vehicles and subsystems for various space projects are discussed. A systematic approach, based on mission requirement analysis, definition of a mission baseline design, benefit and cost analysis, and a benefit-cost analysis was proposed for implementing the cost control program.

A Discussion of Knowledge Based Design

NASA Technical Reports Server (NTRS)

Wood, Richard M.; Bauer, Steven X. S.

1999-01-01

A discussion of knowledge and Knowledge- Based design as related to the design of aircraft is presented. The paper discusses the perceived problem with existing design studies and introduces the concepts of design and knowledge for a Knowledge- Based design system. A review of several Knowledge-Based design activities is provided. A Virtual Reality, Knowledge-Based system is proposed and reviewed. The feasibility of Virtual Reality to improve the efficiency and effectiveness of aerodynamic and multidisciplinary design, evaluation, and analysis of aircraft through the coupling of virtual reality technology and a Knowledge-Based design system is also reviewed. The final section of the paper discusses future directions for design and the role of Knowledge-Based design.

Design Oriented Structural Modeling for Airplane Conceptual Design Optimization

NASA Technical Reports Server (NTRS)

Livne, Eli

1999-01-01

The main goal for research conducted with the support of this grant was to develop design oriented structural optimization methods for the conceptual design of airplanes. Traditionally in conceptual design airframe weight is estimated based on statistical equations developed over years of fitting airplane weight data in data bases of similar existing air- planes. Utilization of such regression equations for the design of new airplanes can be justified only if the new air-planes use structural technology similar to the technology on the airplanes in those weight data bases. If any new structural technology is to be pursued or any new unconventional configurations designed the statistical weight equations cannot be used. In such cases any structural weight estimation must be based on rigorous "physics based" structural analysis and optimization of the airframes under consideration. Work under this grant progressed to explore airframe design-oriented structural optimization techniques along two lines of research: methods based on "fast" design oriented finite element technology and methods based on equivalent plate / equivalent shell models of airframes, in which the vehicle is modelled as an assembly of plate and shell components, each simulating a lifting surface or nacelle / fuselage pieces. Since response to changes in geometry are essential in conceptual design of airplanes, as well as the capability to optimize the shape itself, research supported by this grant sought to develop efficient techniques for parametrization of airplane shape and sensitivity analysis with respect to shape design variables. Towards the end of the grant period a prototype automated structural analysis code designed to work with the NASA Aircraft Synthesis conceptual design code ACS= was delivered to NASA Ames.

Designing an End-to-End System for Data Storage, Analysis, and Visualization for an Urban Environmental Observatory

NASA Astrophysics Data System (ADS)

McGuire, M. P.; Welty, C.; Gangopadhyay, A.; Karabatis, G.; Chen, Z.

2006-05-01

The urban environment is formed by complex interactions between natural and human dominated systems, the study of which requires the collection and analysis of very large datasets that span many disciplines. Recent advances in sensor technology and automated data collection have improved the ability to monitor urban environmental systems and are making the idea of an urban environmental observatory a reality. This in turn has created a number of potential challenges in data management and analysis. We present the design of an end-to-end system to store, analyze, and visualize data from a prototype urban environmental observatory based at the Baltimore Ecosystem Study, a National Science Foundation Long Term Ecological Research site (BES LTER). We first present an object-relational design of an operational database to store high resolution spatial datasets as well as data from sensor networks, archived data from the BES LTER, data from external sources such as USGS NWIS, EPA Storet, and metadata. The second component of the system design includes a spatiotemporal data warehouse consisting of a data staging plan and a multidimensional data model designed for the spatiotemporal analysis of monitoring data. The system design also includes applications for multi-resolution exploratory data analysis, multi-resolution data mining, and spatiotemporal visualization based on the spatiotemporal data warehouse. Also the system design includes interfaces with water quality models such as HSPF, SWMM, and SWAT, and applications for real-time sensor network visualization, data discovery, data download, QA/QC, and backup and recovery, all of which are based on the operational database. The system design includes both internet and workstation-based interfaces. Finally we present the design of a laboratory for spatiotemporal analysis and visualization as well as real-time monitoring of the sensor network.

Performer-centric Interface Design.

ERIC Educational Resources Information Center

McGraw, Karen L.

1995-01-01

Describes performer-centric interface design and explains a model-based approach for conducting performer-centric analysis and design. Highlights include design methodology, including cognitive task analysis; creating task scenarios; creating the presentation model; creating storyboards; proof of concept screens; object models and icons;…

The Research of Computer Aided Farm Machinery Designing Method Based on Ergonomics

NASA Astrophysics Data System (ADS)

Gao, Xiyin; Li, Xinling; Song, Qiang; Zheng, Ying

Along with agricultural economy development, the farm machinery product type Increases gradually, the ergonomics question is also getting more and more prominent. The widespread application of computer aided machinery design makes it possible that farm machinery design is intuitive, flexible and convenient. At present, because the developed computer aided ergonomics software has not suitable human body database, which is needed in view of farm machinery design in China, the farm machinery design have deviation in ergonomics analysis. This article puts forward that using the open database interface procedure in CATIA to establish human body database which aims at the farm machinery design, and reading the human body data to ergonomics module of CATIA can product practical application virtual body, using human posture analysis and human activity analysis module to analysis the ergonomics in farm machinery, thus computer aided farm machinery designing method based on engineering can be realized.

Experimental design based 3-D QSAR analysis of steroid-protein interactions: Application to human CBG complexes

NASA Astrophysics Data System (ADS)

Norinder, Ulf

1990-12-01

An experimental design based 3-D QSAR analysis using a combination of principal component and PLS analysis is presented and applied to human corticosteroid-binding globulin complexes. The predictive capability of the created model is good. The technique can also be used as guidance when selecting new compounds to be investigated.

Reduction method with system analysis for multiobjective optimization-based design

NASA Technical Reports Server (NTRS)

Azarm, S.; Sobieszczanski-Sobieski, J.

1993-01-01

An approach for reducing the number of variables and constraints, which is combined with System Analysis Equations (SAE), for multiobjective optimization-based design is presented. In order to develop a simplified analysis model, the SAE is computed outside an optimization loop and then approximated for use by an operator. Two examples are presented to demonstrate the approach.

Concept Maps as Instructional Tools for Improving Learning of Phase Transitions in Object-Oriented Analysis and Design

ERIC Educational Resources Information Center

Shin, Shin-Shing

2016-01-01

Students attending object-oriented analysis and design (OOAD) courses typically encounter difficulties transitioning from requirements analysis to logical design and then to physical design. Concept maps have been widely used in studies of user learning. The study reported here, based on the relationship of concept maps to learning theory and…

Designing simulator-based training: an approach integrating cognitive task analysis and four-component instructional design.

PubMed

Tjiam, Irene M; Schout, Barbara M A; Hendrikx, Ad J M; Scherpbier, Albert J J M; Witjes, J Alfred; van Merriënboer, Jeroen J G

2012-01-01

Most studies of simulator-based surgical skills training have focused on the acquisition of psychomotor skills, but surgical procedures are complex tasks requiring both psychomotor and cognitive skills. As skills training is modelled on expert performance consisting partly of unconscious automatic processes that experts are not always able to explicate, simulator developers should collaborate with educational experts and physicians in developing efficient and effective training programmes. This article presents an approach to designing simulator-based skill training comprising cognitive task analysis integrated with instructional design according to the four-component/instructional design model. This theory-driven approach is illustrated by a description of how it was used in the development of simulator-based training for the nephrostomy procedure.

A Most Probable Point-Based Method for Reliability Analysis, Sensitivity Analysis and Design Optimization

NASA Technical Reports Server (NTRS)

Hou, Gene J.-W; Newman, Perry A. (Technical Monitor)

2004-01-01

A major step in a most probable point (MPP)-based method for reliability analysis is to determine the MPP. This is usually accomplished by using an optimization search algorithm. The minimum distance associated with the MPP provides a measurement of safety probability, which can be obtained by approximate probability integration methods such as FORM or SORM. The reliability sensitivity equations are derived first in this paper, based on the derivatives of the optimal solution. Examples are provided later to demonstrate the use of these derivatives for better reliability analysis and reliability-based design optimization (RBDO).

An integrated modeling and design tool for advanced optical spacecraft

NASA Technical Reports Server (NTRS)

Briggs, Hugh C.

1992-01-01

Consideration is given to the design and status of the Integrated Modeling of Optical Systems (IMOS) tool and to critical design issues. A multidisciplinary spacecraft design and analysis tool with support for structural dynamics, controls, thermal analysis, and optics, IMOS provides rapid and accurate end-to-end performance analysis, simulations, and optimization of advanced space-based optical systems. The requirements for IMOS-supported numerical arrays, user defined data structures, and a hierarchical data base are outlined, and initial experience with the tool is summarized. A simulation of a flexible telescope illustrates the integrated nature of the tools.

Model-based approach for design verification and co-optimization of catastrophic and parametric-related defects due to systematic manufacturing variations

NASA Astrophysics Data System (ADS)

Perry, Dan; Nakamoto, Mark; Verghese, Nishath; Hurat, Philippe; Rouse, Rich

2007-03-01

Model-based hotspot detection and silicon-aware parametric analysis help designers optimize their chips for yield, area and performance without the high cost of applying foundries' recommended design rules. This set of DFM/ recommended rules is primarily litho-driven, but cannot guarantee a manufacturable design without imposing overly restrictive design requirements. This rule-based methodology of making design decisions based on idealized polygons that no longer represent what is on silicon needs to be replaced. Using model-based simulation of the lithography, OPC, RET and etch effects, followed by electrical evaluation of the resulting shapes, leads to a more realistic and accurate analysis. This analysis can be used to evaluate intelligent design trade-offs and identify potential failures due to systematic manufacturing defects during the design phase. The successful DFM design methodology consists of three parts: 1. Achieve a more aggressive layout through limited usage of litho-related recommended design rules. A 10% to 15% area reduction is achieved by using more aggressive design rules. DFM/recommended design rules are used only if there is no impact on cell size. 2. Identify and fix hotspots using a model-based layout printability checker. Model-based litho and etch simulation are done at the cell level to identify hotspots. Violations of recommended rules may cause additional hotspots, which are then fixed. The resulting design is ready for step 3. 3. Improve timing accuracy with a process-aware parametric analysis tool for transistors and interconnect. Contours of diffusion, poly and metal layers are used for parametric analysis. In this paper, we show the results of this physical and electrical DFM methodology at Qualcomm. We describe how Qualcomm was able to develop more aggressive cell designs that yielded a 10% to 15% area reduction using this methodology. Model-based shape simulation was employed during library development to validate architecture choices and to optimize cell layout. At the physical verification stage, the shape simulator was run at full-chip level to identify and fix residual hotspots on interconnect layers, on poly or metal 1 due to interaction between adjacent cells, or on metal 1 due to interaction between routing (via and via cover) and cell geometry. To determine an appropriate electrical DFM solution, Qualcomm developed an experiment to examine various electrical effects. After reporting the silicon results of this experiment, which showed sizeable delay variations due to lithography-related systematic effects, we also explain how contours of diffusion, poly and metal can be used for silicon-aware parametric analysis of transistors and interconnect at the cell-, block- and chip-level.

10 CFR 72.3 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... of the property under restricted conditions and termination of the license. Design bases means that... events include— (1) Estimates of severe natural events to be used for deriving design bases that will be... to be used for deriving design bases that will be based on analysis of human activity in the region...

Titanium and advanced composite structures for a supersonic cruise arrow wing configuration

NASA Technical Reports Server (NTRS)

Turner, M. J.; Hoy, J. M.

1976-01-01

Structural design studies were made, based on current technology and on an estimate of technology to be available in the mid 1980's, to assess the relative merits of structural concepts and materials for an advanced arrow wing configuration cruising at Mach 2.7. Preliminary studies were made to insure compliance of the configuration with general design criteria, integrate the propulsion system with the airframe, and define an efficient structural arrangement. Material and concept selection, detailed structural analysis, structural design and airplane mass analysis were completed based on current technology. Based on estimated future technology, structural sizing for strength and a preliminary assessment of the flutter of a strength designed composite structure were completed. An advanced computerized structural design system was used, in conjunction with a relatively complex finite element model, for detailed analysis and sizing of structural members.

Cognitive Task Analysis for Instructional Design: Applications in Distance Education.

ERIC Educational Resources Information Center

Redding, Richard E.

1995-01-01

Provides an overview of cognitive task analysis-based instructional design (CTA-BID) and its applications in the design of instructional and testing materials for distance education. Reviews developments in education, psychology, and instructional design that complement CTA-BID. (Author/AEF)

Concepts for the development of light-weight composite structures for rotor burst containment

NASA Technical Reports Server (NTRS)

Holms, A. G.

1977-01-01

Based on published results on rotor burst containment with single materials, and on body armor using composite materials, a set of hypotheses is established as to what variables might control the design of a weight-efficient protective device. Based on modern concepts for the design and analysis of small optimum seeking experiments, a particular experiment for evaluating the hypotheses and materials was designed. The design and methods for the analysis of results are described.

A Model-Based Systems Engineering Methodology for Employing Architecture In System Analysis: Developing Simulation Models Using Systems Modeling Language Products to Link Architecture and Analysis

DTIC Science & Technology

2016-06-01

characteristics, experimental design techniques, and analysis methodologies that distinguish each phase of the MBSE MEASA. To ensure consistency... methodology . Experimental design selection, simulation analysis, and trade space analysis support the final two stages. Figure 27 segments the MBSE MEASA...rounding has the potential to increase the correlation between columns of the experimental design matrix. The design methodology presented in Vieira

Coal conversion processes and analysis methodologies for synthetic fuels production. [technology assessment and economic analysis of reactor design for coal gasification

NASA Technical Reports Server (NTRS)

1979-01-01

Information to identify viable coal gasification and utilization technologies is presented. Analysis capabilities required to support design and implementation of coal based synthetic fuels complexes are identified. The potential market in the Southeast United States for coal based synthetic fuels is investigated. A requirements analysis to identify the types of modeling and analysis capabilities required to conduct and monitor coal gasification project designs is discussed. Models and methodologies to satisfy these requirements are identified and evaluated, and recommendations are developed. Requirements for development of technology and data needed to improve gasification feasibility and economies are examined.

Finite element analysis on the bending condition of truck frame before and after opening

NASA Astrophysics Data System (ADS)

Cai, Kaiwu; Cheng, Wei; Lu, Jifu

2018-05-01

Based on the design parameters of a truck frame, the structure design and model of the truck frame are built. Based on the finite element theory, the load, the type of fatigue and the material parameters of the frame are combined with the semi-trailer. Using finite element analysis software, after a truck frame hole in bending condition for the finite element analysis of comparison, through the analysis found that the truck frame hole under bending condition can meet the strength requirements are very helpful for improving the design of the truck frame.

Inlet Development for a Rocket Based Combined Cycle, Single Stage to Orbit Vehicle Using Computational Fluid Dynamics

NASA Technical Reports Server (NTRS)

DeBonis, J. R.; Trefny, C. J.; Steffen, C. J., Jr.

1999-01-01

Design and analysis of the inlet for a rocket based combined cycle engine is discussed. Computational fluid dynamics was used in both the design and subsequent analysis. Reynolds averaged Navier-Stokes simulations were performed using both perfect gas and real gas assumptions. An inlet design that operates over the required Mach number range from 0 to 12 was produced. Performance data for cycle analysis was post processed using a stream thrust averaging technique. A detailed performance database for cycle analysis is presented. The effect ot vehicle forebody compression on air capture is also examined.

Analysis of pre-service physics teacher skills designing simple physics experiments based technology

NASA Astrophysics Data System (ADS)

Susilawati; Huda, C.; Kurniawan, W.; Masturi; Khoiri, N.

2018-03-01

Pre-service physics teacher skill in designing simple experiment set is very important in adding understanding of student concept and practicing scientific skill in laboratory. This study describes the skills of physics students in designing simple experiments based technologicall. The experimental design stages include simple tool design and sensor modification. The research method used is descriptive method with the number of research samples 25 students and 5 variations of simple physics experimental design. Based on the results of interviews and observations obtained the results of pre-service physics teacher skill analysis in designing simple experimental physics charged technology is good. Based on observation result, pre-service physics teacher skill in designing simple experiment is good while modification and sensor application are still not good. This suggests that pre-service physics teacher still need a lot of practice and do experiments in designing physics experiments using sensor modifications. Based on the interview result, it is found that students have high enough motivation to perform laboratory activities actively and students have high curiosity to be skilled at making simple practicum tool for physics experiment.

Design, development and testing twin pulse tube cryocooler

NASA Astrophysics Data System (ADS)

Gour, Abhay Singh; Sagar, Pankaj; Karunanithi, R.

2017-09-01

The design and development of Twin Pulse Tube Cryocooler (TPTC) is presented. Both the coolers are driven by a single Linear Moving Magnet Synchronous Motor (LMMSM) with piston heads at both ends of the mover shaft. Magnetostatic analysis for flux line distribution was carried-out during design and development of LMMSM based pressure wave generator. Based on the performance of PWG, design of TPTC was carried out using Sage and Computational Fluid Dynamics (CFD) analysis. Detailed design, fabrication and testing of LMMSM, TPTC and their integration tests are presented in this paper.

Design of impact-resistant boron/aluminum large fan blade

NASA Technical Reports Server (NTRS)

Salemme, C. T.; Yokel, S. A.

1978-01-01

The technical program was comprised of two technical tasks. Task 1 encompassed the preliminary boron/aluminum fan blade design effort. Two preliminary designs were evolved. An initial design consisted of 32 blades per stage and was based on material properties extracted from manufactured blades. A final design of 36 blades per stage was based on rule-of-mixture material properties. In Task 2, the selected preliminary blade design was refined via more sophisticated analytical tools. Detailed finite element stress analysis and aero performance analysis were carried out to determine blade material frequencies and directional stresses.

Team-Based Peer Review as a Form of Formative Assessment--The Case of a Systems Analysis and Design Workshop

ERIC Educational Resources Information Center

Lavy, Ilana; Yadin, Aharon

2010-01-01

The present study was carried out within a systems analysis and design workshop. In addition to the standard analysis and design tasks, this workshop included practices designed to enhance student capabilities related to non-technical knowledge areas, such as critical thinking, interpersonal and team skills, and business understanding. Each task…

A preliminary structural analysis of space-base living quarters modules to verify a weight-estimating technique

NASA Technical Reports Server (NTRS)

Grissom, D. S.; Schneider, W. C.

1971-01-01

The determination of a base line (minimum weight) design for the primary structure of the living quarters modules in an earth-orbiting space base was investigated. Although the design is preliminary in nature, the supporting analysis is sufficiently thorough to provide a reasonably accurate weight estimate of the major components that are considered to comprise the structural weight of the space base.

Computational electronics and electromagnetics

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

Shang, C. C.

The Computational Electronics and Electromagnetics thrust area at Lawrence Livermore National Laboratory serves as the focal point for engineering R&D activities for developing computer-based design, analysis, and tools for theory. Key representative applications include design of particle accelerator cells and beamline components; engineering analysis and design of high-power components, photonics, and optoelectronics circuit design; EMI susceptibility analysis; and antenna synthesis. The FY-96 technology-base effort focused code development on (1) accelerator design codes; (2) 3-D massively parallel, object-oriented time-domain EM codes; (3) material models; (4) coupling and application of engineering tools for analysis and design of high-power components; (5) 3-D spectral-domainmore » CEM tools; and (6) enhancement of laser drilling codes. Joint efforts with the Power Conversion Technologies thrust area include development of antenna systems for compact, high-performance radar, in addition to novel, compact Marx generators. 18 refs., 25 figs., 1 tab.« less

Computer-aided system of evaluation for population-based all-in-one service screening (CASE-PASS): from study design to outcome analysis with bias adjustment.

PubMed

Chen, Li-Sheng; Yen, Amy Ming-Fang; Duffy, Stephen W; Tabar, Laszlo; Lin, Wen-Chou; Chen, Hsiu-Hsi

2010-10-01

Population-based routine service screening has gained popularity following an era of randomized controlled trials. The evaluation of these service screening programs is subject to study design, data availability, and the precise data analysis for adjusting bias. We developed a computer-aided system that allows the evaluation of population-based service screening to unify these aspects and facilitate and guide the program assessor to efficiently perform an evaluation. This system underpins two experimental designs: the posttest-only non-equivalent design and the one-group pretest-posttest design and demonstrates the type of data required at both the population and individual levels. Three major analyses were developed that included a cumulative mortality analysis, survival analysis with lead-time adjustment, and self-selection bias adjustment. We used SAS AF software to develop a graphic interface system with a pull-down menu style. We demonstrate the application of this system with data obtained from a Swedish population-based service screen and a population-based randomized controlled trial for the screening of breast, colorectal, and prostate cancer, and one service screening program for cervical cancer with Pap smears. The system provided automated descriptive results based on the various sources of available data and cumulative mortality curves corresponding to the study designs. The comparison of cumulative survival between clinically and screen-detected cases without a lead-time adjustment are also demonstrated. The intention-to-treat and noncompliance analysis with self-selection bias adjustments are also shown to assess the effectiveness of the population-based service screening program. Model validation was composed of a comparison between our adjusted self-selection bias estimates and the empirical results on effectiveness reported in the literature. We demonstrate a computer-aided system allowing the evaluation of population-based service screening programs with an adjustment for self-selection and lead-time bias. This is achieved by providing a tutorial guide from the study design to the data analysis, with bias adjustment. Copyright © 2010 Elsevier Inc. All rights reserved.

Loads and low frequency dynamics - An ENVIRONET data base

NASA Technical Reports Server (NTRS)

Garba, John A.

1988-01-01

The loads and low frequency dynamics data base, part of Environet, is described with particular attention given to its development and contents. The objective of the data base is to provide the payload designer with design approaches and design data to meet STS safety requirements. Currently the data base consists of the following sections: abstract, scope, glossary, requirements, interaction with other environments, summary of the loads analysis process, design considerations, guidelines for payload design loads, information data base, and references.

Design-Based Research: Case of a Teaching Sequence on Mechanics

ERIC Educational Resources Information Center

Tiberghien, Andree; Vince, Jacques; Gaidioz, Pierre

2009-01-01

Design-based research, and particularly its theoretical status, is a subject of debate in the science education community. In the first part of this paper, a theoretical framework drawn up to develop design-based research will be presented. This framework is mainly based on epistemological analysis of physics modelling, learning and teaching…

A unifying framework for systems modeling, control systems design, and system operation

NASA Technical Reports Server (NTRS)

Dvorak, Daniel L.; Indictor, Mark B.; Ingham, Michel D.; Rasmussen, Robert D.; Stringfellow, Margaret V.

2005-01-01

Current engineering practice in the analysis and design of large-scale multi-disciplinary control systems is typified by some form of decomposition- whether functional or physical or discipline-based-that enables multiple teams to work in parallel and in relative isolation. Too often, the resulting system after integration is an awkward marriage of different control and data mechanisms with poor end-to-end accountability. System of systems engineering, which faces this problem on a large scale, cries out for a unifying framework to guide analysis, design, and operation. This paper describes such a framework based on a state-, model-, and goal-based architecture for semi-autonomous control systems that guides analysis and modeling, shapes control system software design, and directly specifies operational intent. This paper illustrates the key concepts in the context of a large-scale, concurrent, globally distributed system of systems: NASA's proposed Array-based Deep Space Network.

Army Transformation in the Age of Globalization - Implementing Directed Change with Strategic Management Design (SMD): An Analysis Based on the Army Staff in the German Ministry of Defense

DTIC Science & Technology

2008-05-01

researched and tested in the U.S. Army during the Unified Quest exercise series, design of military campaigns occurs in the complex globalized environment...Army Transformation in the Age of Globalization – Implementing Directed Change with Strategic Management Design (SMD) An Analysis based on the...the Age of globalization – Implementing Direction Change with Strategic Management Design (SMD). 5c. PROGRAM ELEMENT NUMBER 5d. PROJECT NUMBER

Research and analysis of head-directed area-of-interest visual system concepts

NASA Technical Reports Server (NTRS)

Sinacori, J. B.

1983-01-01

An analysis and survey with conjecture supporting a preliminary data base design is presented. The data base is intended for use in a Computer Image Generator visual subsystem for a rotorcraft flight simulator that is used for rotorcraft systems development, not training. The approach taken was to attempt to identify the visual perception strategies used during terrain flight, survey environmental and image generation factors, and meld these into a preliminary data base design. This design is directed at Data Base developers, and hopefully will stimulate and aid their efforts to evolve such a Base that will support simulation of terrain flight operations.

SLS Navigation Model-Based Design Approach

NASA Technical Reports Server (NTRS)

Oliver, T. Emerson; Anzalone, Evan; Geohagan, Kevin; Bernard, Bill; Park, Thomas

2018-01-01

The SLS Program chose to implement a Model-based Design and Model-based Requirements approach for managing component design information and system requirements. This approach differs from previous large-scale design efforts at Marshall Space Flight Center where design documentation alone conveyed information required for vehicle design and analysis and where extensive requirements sets were used to scope and constrain the design. The SLS Navigation Team has been responsible for the Program-controlled Design Math Models (DMMs) which describe and represent the performance of the Inertial Navigation System (INS) and the Rate Gyro Assemblies (RGAs) used by Guidance, Navigation, and Controls (GN&C). The SLS Navigation Team is also responsible for the navigation algorithms. The navigation algorithms are delivered for implementation on the flight hardware as a DMM. For the SLS Block 1-B design, the additional GPS Receiver hardware is managed as a DMM at the vehicle design level. This paper provides a discussion of the processes and methods used to engineer, design, and coordinate engineering trades and performance assessments using SLS practices as applied to the GN&C system, with a particular focus on the Navigation components. These include composing system requirements, requirements verification, model development, model verification and validation, and modeling and analysis approaches. The Model-based Design and Requirements approach does not reduce the effort associated with the design process versus previous processes used at Marshall Space Flight Center. Instead, the approach takes advantage of overlap between the requirements development and management process, and the design and analysis process by efficiently combining the control (i.e. the requirement) and the design mechanisms. The design mechanism is the representation of the component behavior and performance in design and analysis tools. The focus in the early design process shifts from the development and management of design requirements to the development of usable models, model requirements, and model verification and validation efforts. The models themselves are represented in C/C++ code and accompanying data files. Under the idealized process, potential ambiguity in specification is reduced because the model must be implementable versus a requirement which is not necessarily subject to this constraint. Further, the models are shown to emulate the hardware during validation. For models developed by the Navigation Team, a common interface/standalone environment was developed. The common environment allows for easy implementation in design and analysis tools. Mechanisms such as unit test cases ensure implementation as the developer intended. The model verification and validation process provides a very high level of component design insight. The origin and implementation of the SLS variant of Model-based Design is described from the perspective of the SLS Navigation Team. The format of the models and the requirements are described. The Model-based Design approach has many benefits but is not without potential complications. Key lessons learned associated with the implementation of the Model Based Design approach and process from infancy to verification and certification are discussed

Study on store-space assignment based on logistic AGV in e-commerce goods to person picking pattern

NASA Astrophysics Data System (ADS)

Xu, Lijuan; Zhu, Jie

2017-10-01

This paper studied on the store-space assignment based on logistic AGV in E-commerce goods to person picking pattern, and established the store-space assignment model based on the lowest picking cost, and design for store-space assignment algorithm after the cluster analysis based on similarity coefficient. And then through the example analysis, compared the picking cost between store-space assignment algorithm this paper design and according to item number and storage according to ABC classification allocation, and verified the effectiveness of the design of the store-space assignment algorithm.

Reasserting the Fundamentals of Systems Analysis and Design through the Rudiments of Artifacts

ERIC Educational Resources Information Center

Jafar, Musa; Babb, Jeffry

2012-01-01

In this paper we present an artifacts-based approach to teaching a senior level Object-Oriented Analysis and Design course. Regardless of the systems development methodology and process model, and in order to facilitate communication across the business modeling, analysis, design, construction and deployment disciplines, we focus on (1) the…

Study on the Theoretical Foundation of Business English Curriculum Design Based on ESP and Needs Analysis

ERIC Educational Resources Information Center

Zhu, Wenzhong; Liu, Dan

2014-01-01

Based on a review of the literature on ESP and needs analysis, this paper is intended to offer some theoretical supports and inspirations for BE instructors to develop BE curricula for business contexts. It discusses how the theory of need analysis can be used in Business English curriculum design, and proposes some principles of BE curriculum…

Natural Resource Information System, design analysis

NASA Technical Reports Server (NTRS)

1972-01-01

The computer-based system stores, processes, and displays map data relating to natural resources. The system was designed on the basis of requirements established in a user survey and an analysis of decision flow. The design analysis effort is described, and the rationale behind major design decisions, including map processing, cell vs. polygon, choice of classification systems, mapping accuracy, system hardware, and software language is summarized.

Multidisciplinary Analysis and Optimal Design: As Easy as it Sounds?

NASA Technical Reports Server (NTRS)

Moore, Greg; Chainyk, Mike; Schiermeier, John

2004-01-01

The viewgraph presentation examines optimal design for precision, large aperture structures. Discussion focuses on aspects of design optimization, code architecture and current capabilities, and planned activities and collaborative area suggestions. The discussion of design optimization examines design sensitivity analysis; practical considerations; and new analytical environments including finite element-based capability for high-fidelity multidisciplinary analysis, design sensitivity, and optimization. The discussion of code architecture and current capabilities includes basic thermal and structural elements, nonlinear heat transfer solutions and process, and optical modes generation.

TADS--A CFD-Based Turbomachinery Analysis and Design System with GUI: User's Manual. 2.0

NASA Technical Reports Server (NTRS)

Koiro, M. J.; Myers, R. A.; Delaney, R. A.

1999-01-01

The primary objective of this study was the development of a Computational Fluid Dynamics (CFD) based turbomachinery airfoil analysis and design system, controlled by a Graphical User Interface (GUI). The computer codes resulting from this effort are referred to as TADS (Turbomachinery Analysis and Design System). This document is intended to serve as a User's Manual for the computer programs which comprise the TADS system, developed under Task 18 of NASA Contract NAS3-27350, ADPAC System Coupling to Blade Analysis & Design System GUI and Task 10 of NASA Contract NAS3-27394, ADPAC System Coupling to Blade Analysis & Design System GUI, Phase II-Loss, Design and, Multi-stage Analysis. TADS couples a throughflow solver (ADPAC) with a quasi-3D blade-to-blade solver (RVCQ3D) in an interactive package. Throughflow analysis and design capability was developed in ADPAC through the addition of blade force and blockage terms to the governing equations. A GUI was developed to simplify user input and automate the many tasks required to perform turbomachinery analysis and design. The coupling of the various programs was done in such a way that alternative solvers or grid generators could be easily incorporated into the TADS framework. Results of aerodynamic calculations using the TADS system are presented for a highly loaded fan, a compressor stator, a low speed turbine blade and a transonic turbine vane.

Adjoint-Based Aerodynamic Design of Complex Aerospace Configurations

NASA Technical Reports Server (NTRS)

Nielsen, Eric J.

2016-01-01

An overview of twenty years of adjoint-based aerodynamic design research at NASA Langley Research Center is presented. Adjoint-based algorithms provide a powerful tool for efficient sensitivity analysis of complex large-scale computational fluid dynamics (CFD) simulations. Unlike alternative approaches for which computational expense generally scales with the number of design parameters, adjoint techniques yield sensitivity derivatives of a simulation output with respect to all input parameters at the cost of a single additional simulation. With modern large-scale CFD applications often requiring millions of compute hours for a single analysis, the efficiency afforded by adjoint methods is critical in realizing a computationally tractable design optimization capability for such applications.

An example problem illustrating the application of the national lime association mixture design and testing protocol (MDTP) to ascertain engineering properties of lime-treated subgrades for mechanistic pavement design/analysis.

DOT National Transportation Integrated Search

2001-09-01

This document presents an example of mechanistic design and analysis using a mix design and : testing protocol. More specifically, it addresses the structural properties of lime-treated subgrade, : subbase, and base layers through mechanistic design ...

Designing Industrial Networks Using Ecological Food Web Metrics.

PubMed

Layton, Astrid; Bras, Bert; Weissburg, Marc

2016-10-18

Biologically Inspired Design (biomimicry) and Industrial Ecology both look to natural systems to enhance the sustainability and performance of engineered products, systems and industries. Bioinspired design (BID) traditionally has focused on a unit operation and single product level. In contrast, this paper describes how principles of network organization derived from analysis of ecosystem properties can be applied to industrial system networks. Specifically, this paper examines the applicability of particular food web matrix properties as design rules for economically and biologically sustainable industrial networks, using an optimization model developed for a carpet recycling network. Carpet recycling network designs based on traditional cost and emissions based optimization are compared to designs obtained using optimizations based solely on ecological food web metrics. The analysis suggests that networks optimized using food web metrics also were superior from a traditional cost and emissions perspective; correlations between optimization using ecological metrics and traditional optimization ranged generally from 0.70 to 0.96, with flow-based metrics being superior to structural parameters. Four structural food parameters provided correlations nearly the same as that obtained using all structural parameters, but individual structural parameters provided much less satisfactory correlations. The analysis indicates that bioinspired design principles from ecosystems can lead to both environmentally and economically sustainable industrial resource networks, and represent guidelines for designing sustainable industry networks.

Structural design of composite rotor blades with consideration of manufacturability, durability, and manufacturing uncertainties

NASA Astrophysics Data System (ADS)

Li, Leihong

A modular structural design methodology for composite blades is developed. This design method can be used to design composite rotor blades with sophisticate geometric cross-sections. This design method hierarchically decomposed the highly-coupled interdisciplinary rotor analysis into global and local levels. In the global level, aeroelastic response analysis and rotor trim are conduced based on multi-body dynamic models. In the local level, variational asymptotic beam sectional analysis methods are used for the equivalent one-dimensional beam properties. Compared with traditional design methodology, the proposed method is more efficient and accurate. Then, the proposed method is used to study three different design problems that have not been investigated before. The first is to add manufacturing constraints into design optimization. The introduction of manufacturing constraints complicates the optimization process. However, the design with manufacturing constraints benefits the manufacturing process and reduces the risk of violating major performance constraints. Next, a new design procedure for structural design against fatigue failure is proposed. This procedure combines the fatigue analysis with the optimization process. The durability or fatigue analysis employs a strength-based model. The design is subject to stiffness, frequency, and durability constraints. Finally, the manufacturing uncertainty impacts on rotor blade aeroelastic behavior are investigated, and a probabilistic design method is proposed to control the impacts of uncertainty on blade structural performance. The uncertainty factors include dimensions, shapes, material properties, and service loads.

Observations Regarding Use of Advanced CFD Analysis, Sensitivity Analysis, and Design Codes in MDO

NASA Technical Reports Server (NTRS)

Newman, Perry A.; Hou, Gene J. W.; Taylor, Arthur C., III

1996-01-01

Observations regarding the use of advanced computational fluid dynamics (CFD) analysis, sensitivity analysis (SA), and design codes in gradient-based multidisciplinary design optimization (MDO) reflect our perception of the interactions required of CFD and our experience in recent aerodynamic design optimization studies using CFD. Sample results from these latter studies are summarized for conventional optimization (analysis - SA codes) and simultaneous analysis and design optimization (design code) using both Euler and Navier-Stokes flow approximations. The amount of computational resources required for aerodynamic design using CFD via analysis - SA codes is greater than that required for design codes. Thus, an MDO formulation that utilizes the more efficient design codes where possible is desired. However, in the aerovehicle MDO problem, the various disciplines that are involved have different design points in the flight envelope; therefore, CFD analysis - SA codes are required at the aerodynamic 'off design' points. The suggested MDO formulation is a hybrid multilevel optimization procedure that consists of both multipoint CFD analysis - SA codes and multipoint CFD design codes that perform suboptimizations.

The Design of a Graphical User Interface for an Electronic Classroom.

ERIC Educational Resources Information Center

Cahalan, Kathleen J.; Levin, Jacques

2000-01-01

Describes the design of a prototype for the graphical user interface component of an electronic classroom (ECR) application that supports real-time lectures and question-and-answer sessions between an instructor and students. Based on requirements analysis and an analysis of competing products, a Web-based ECR prototype was produced. Findings show…

Life-Cycle Analysis and Inquiry-Based Learning in Chemistry Teaching

ERIC Educational Resources Information Center

Juntunen, Marianne; Aksela, Maija

2013-01-01

The purpose of this design research is to improve the quality of environmental literacy and sustainability education in chemistry teaching through combining a socio-scientific issue, life-cycle analysis (LCA), with inquiry-based learning (IBL). This first phase of the cyclic design research involved 20 inservice trained chemistry teachers from…

Conditional analysis of mixed Poisson processes with baseline counts: implications for trial design and analysis.

PubMed

Cook, Richard J; Wei, Wei

2003-07-01

The design of clinical trials is typically based on marginal comparisons of a primary response under two or more treatments. The considerable gains in efficiency afforded by models conditional on one or more baseline responses has been extensively studied for Gaussian models. The purpose of this article is to present methods for the design and analysis of clinical trials in which the response is a count or a point process, and a corresponding baseline count is available prior to randomization. The methods are based on a conditional negative binomial model for the response given the baseline count and can be used to examine the effect of introducing selection criteria on power and sample size requirements. We show that designs based on this approach are more efficient than those proposed by McMahon et al. (1994).

A Participatory Design Approach for a Mobile App-Based Personal Response System

ERIC Educational Resources Information Center

Song, Donggil; Oh, Eun Young

2016-01-01

This study reports on a participatory design approach including the design, development, implementation, and evaluation of a mobile app-based personal response system (PRS). The first cycle formulated initial design principles through context and needs analysis; the second utilized the collaboration with instructors and experts embodying specific…

Comparative Analysis.

DTIC Science & Technology

1987-11-01

differential qualita- tive (DQ) analysis, which solves the task, providing explanations suitable for use by design systems, automated diagnosis, intelligent...solves the task, providing explanations suitable for use by design systems, automated diagnosis, intelligent tutoring systems, and explanation based...comparative analysis as an important component; the explanation is used in many different ways. * One way method of automated design is the principlvd

The Historical and Situated Nature Design Experiments--Implications for Data Analysis

ERIC Educational Resources Information Center

Krange, I.; Ludvigsen, Sten

2009-01-01

This article is a methodological contribution to the use of design experiments in educational research. We will discuss the implications of a historical and situated interpretation to design experiments, the consequences this has for the analysis of the collected data and empirically based suggestions to improve the designs of the computer-based…

A Method for Generating Reduced Order Linear Models of Supersonic Inlets

NASA Technical Reports Server (NTRS)

Chicatelli, Amy; Hartley, Tom T.

1997-01-01

For the modeling of high speed propulsion systems, there are at least two major categories of models. One is based on computational fluid dynamics (CFD), and the other is based on design and analysis of control systems. CFD is accurate and gives a complete view of the internal flow field, but it typically has many states and runs much slower dm real-time. Models based on control design typically run near real-time but do not always capture the fundamental dynamics. To provide improved control models, methods are needed that are based on CFD techniques but yield models that are small enough for control analysis and design.

Collaborative Core Research Program for Chemical-Biological Warfare Defense

DTIC Science & Technology

2015-01-04

Discovery through High Throughput Screening (HTS) and Fragment-Based Drug Design (FBDD...Discovery through High Throughput Screening (HTS) and Fragment-Based Drug Design (FBDD) Current pharmaceutical approaches involving drug discovery...structural analysis and docking program generally known as fragment based drug design (FBDD). The main advantage of using these approaches is that

An Analysis of Teaching Competence in Science Teachers Involved in the Design of Context-Based Curriculum Materials

ERIC Educational Resources Information Center

De Putter-Smits, Lesley G. A.; Taconis, Ruurd; Jochems, Wim; Van Driel, Jan

2012-01-01

The committees for the current Dutch context-based innovation in secondary science education employed teachers to design context-based curriculum materials. A study on the learning of science teachers in design teams for context-based curriculum materials is presented in this paper. In a correlation study, teachers with (n = 5 and 840 students)…

Dakota, a multilevel parallel object-oriented framework for design optimization, parameter estimation, uncertainty quantification, and sensitivity analysis :

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

Adams, Brian M.; Ebeida, Mohamed Salah; Eldred, Michael S.

The Dakota (Design Analysis Kit for Optimization and Terascale Applications) toolkit provides a exible and extensible interface between simulation codes and iterative analysis methods. Dakota contains algorithms for optimization with gradient and nongradient-based methods; uncertainty quanti cation with sampling, reliability, and stochastic expansion methods; parameter estimation with nonlinear least squares methods; and sensitivity/variance analysis with design of experiments and parameter study methods. These capabilities may be used on their own or as components within advanced strategies such as surrogate-based optimization, mixed integer nonlinear programming, or optimization under uncertainty. By employing object-oriented design to implement abstractions of the key components requiredmore » for iterative systems analyses, the Dakota toolkit provides a exible and extensible problem-solving environment for design and performance analysis of computational models on high performance computers. This report serves as a user's manual for the Dakota software and provides capability overviews and procedures for software execution, as well as a variety of example studies.« less

Developing safety performance functions incorporating reliability-based risk measures.

PubMed

Ibrahim, Shewkar El-Bassiouni; Sayed, Tarek

2011-11-01

Current geometric design guides provide deterministic standards where the safety margin of the design output is generally unknown and there is little knowledge of the safety implications of deviating from these standards. Several studies have advocated probabilistic geometric design where reliability analysis can be used to account for the uncertainty in the design parameters and to provide a risk measure of the implication of deviation from design standards. However, there is currently no link between measures of design reliability and the quantification of safety using collision frequency. The analysis presented in this paper attempts to bridge this gap by incorporating a reliability-based quantitative risk measure such as the probability of non-compliance (P(nc)) in safety performance functions (SPFs). Establishing this link will allow admitting reliability-based design into traditional benefit-cost analysis and should lead to a wider application of the reliability technique in road design. The present application is concerned with the design of horizontal curves, where the limit state function is defined in terms of the available (supply) and stopping (demand) sight distances. A comprehensive collision and geometric design database of two-lane rural highways is used to investigate the effect of the probability of non-compliance on safety. The reliability analysis was carried out using the First Order Reliability Method (FORM). Two Negative Binomial (NB) SPFs were developed to compare models with and without the reliability-based risk measures. It was found that models incorporating the P(nc) provided a better fit to the data set than the traditional (without risk) NB SPFs for total, injury and fatality (I+F) and property damage only (PDO) collisions. Copyright © 2011 Elsevier Ltd. All rights reserved.

Analysis of a Preloaded Bolted Joint in a Ceramic Composite Combustor

NASA Technical Reports Server (NTRS)

Hissam, D. Andy; Bower, Mark V.

2003-01-01

This paper presents the detailed analysis of a preloaded bolted joint incorporating ceramic materials. The objective of this analysis is to determine the suitability of a joint design for a ceramic combustor. The analysis addresses critical factors in bolted joint design including preload, preload uncertainty, and load factor. The relationship between key joint variables is also investigated. The analysis is based on four key design criteria, each addressing an anticipated failure mode. The criteria are defined in terms of margin of safety, which must be greater than zero for the design criteria to be satisfied. Since the proposed joint has positive margins of safety, the design criteria are satisfied. Therefore, the joint design is acceptable.

RF control at SSCL — an object oriented design approach

NASA Astrophysics Data System (ADS)

Dohan, D. A.; Osberg, E.; Biggs, R.; Bossom, J.; Chillara, K.; Richter, R.; Wade, D.

1994-12-01

The Superconducting Super Collider (SSC) in Texas, the construction of which was stopped in 1994, would have represented a major challenge in accelerator research and development. This paper addresses the issues encountered in the parallel design and construction of the control systems for the RF equipment for the five accelerators comprising the SSC. An extensive analysis of the components of the RF control systems has been undertaken, based upon the Schlaer-Mellor object-oriented analysis and design (OOA/OOD) methodology. The RF subsystem components such as amplifiers, tubes, power supplies, PID loops, etc. were analyzed to produce OOA information, behavior and process models. Using these models, OOD was iteratively applied to develop a generic RF control system design. This paper describes the results of this analysis and the development of 'bridges' between the analysis objects, and the EPICS-based software and underlying VME-based hardware architectures. The application of this approach to several of the SSCL RF control systems is discussed.

A Meta-Analysis and Review of Holistic Face Processing

PubMed Central

Richler, Jennifer J.; Gauthier, Isabel

2014-01-01

The concept of holistic processing is a cornerstone of face recognition research, yet central questions related to holistic processing remain unanswered, and debates have thus far failed to reach a resolution despite accumulating empirical evidence. We argue that a considerable source of confusion in this literature stems from a methodological problem. Specifically, two different measures of holistic processing based on the composite paradigm (complete design and partial design) are used in the literature, but they often lead to qualitatively different results. First, we present a comprehensive review of the work that directly compares the two designs, and which clearly favors the complete design over the partial design. Second, we report a meta-analysis of holistic face processing according to both designs, and use this as further evidence for one design over the other. The meta-analysis effect size of holistic processing in the complete design is nearly three times that of the partial design. Effect sizes were not correlated between measures, consistent with the suggestion that they do not measure the same thing. Our meta-analysis also examines the correlation between conditions in the complete design of the composite task, and suggests that in an individual differences context, little is gained by including a misaligned baseline. Finally, we offer a comprehensive review of the state of knowledge about holistic processing based on evidence gathered from the measure we favor based on the first sections of our review—the complete design—and outline outstanding research questions in that new context. PMID:24956123

Dakota, a multilevel parallel object-oriented framework for design optimization, parameter estimation, uncertainty quantification, and sensitivity analysis version 6.0 theory manual

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

Adams, Brian M.; Ebeida, Mohamed Salah; Eldred, Michael S

The Dakota (Design Analysis Kit for Optimization and Terascale Applications) toolkit provides a exible and extensible interface between simulation codes and iterative analysis methods. Dakota contains algorithms for optimization with gradient and nongradient-based methods; uncertainty quanti cation with sampling, reliability, and stochastic expansion methods; parameter estimation with nonlinear least squares methods; and sensitivity/variance analysis with design of experiments and parameter study methods. These capabilities may be used on their own or as components within advanced strategies such as surrogate-based optimization, mixed integer nonlinear programming, or optimization under uncertainty. By employing object-oriented design to implement abstractions of the key components requiredmore » for iterative systems analyses, the Dakota toolkit provides a exible and extensible problem-solving environment for design and performance analysis of computational models on high performance computers. This report serves as a theoretical manual for selected algorithms implemented within the Dakota software. It is not intended as a comprehensive theoretical treatment, since a number of existing texts cover general optimization theory, statistical analysis, and other introductory topics. Rather, this manual is intended to summarize a set of Dakota-related research publications in the areas of surrogate-based optimization, uncertainty quanti cation, and optimization under uncertainty that provide the foundation for many of Dakota's iterative analysis capabilities.« less

TADS: A CFD-based turbomachinery and analysis design system with GUI. Volume 2: User's manual

NASA Technical Reports Server (NTRS)

Myers, R. A.; Topp, D. A.; Delaney, R. A.

1995-01-01

The primary objective of this study was the development of a computational fluid dynamics (CFD) based turbomachinery airfoil analysis and design system, controlled by a graphical user interface (GUI). The computer codes resulting from this effort are referred to as the Turbomachinery Analysis and Design System (TADS). This document is intended to serve as a user's manual for the computer programs which comprise the TADS system. TADS couples a throughflow solver (ADPAC) with a quasi-3D blade-to-blade solver (RVCQ3D) in an interactive package. Throughflow analysis capability was developed in ADPAC through the addition of blade force and blockage terms to the governing equations. A GUI was developed to simplify user input and automate the many tasks required to perform turbomachinery analysis and design. The coupling of various programs was done in a way that alternative solvers or grid generators could be easily incorporated into the TADS framework.

Design synthesis and optimization of permanent magnet synchronous machines based on computationally-efficient finite element analysis

NASA Astrophysics Data System (ADS)

Sizov, Gennadi Y.

In this dissertation, a model-based multi-objective optimal design of permanent magnet ac machines, supplied by sine-wave current regulated drives, is developed and implemented. The design procedure uses an efficient electromagnetic finite element-based solver to accurately model nonlinear material properties and complex geometric shapes associated with magnetic circuit design. Application of an electromagnetic finite element-based solver allows for accurate computation of intricate performance parameters and characteristics. The first contribution of this dissertation is the development of a rapid computational method that allows accurate and efficient exploration of large multi-dimensional design spaces in search of optimum design(s). The computationally efficient finite element-based approach developed in this work provides a framework of tools that allow rapid analysis of synchronous electric machines operating under steady-state conditions. In the developed modeling approach, major steady-state performance parameters such as, winding flux linkages and voltages, average, cogging and ripple torques, stator core flux densities, core losses, efficiencies and saturated machine winding inductances, are calculated with minimum computational effort. In addition, the method includes means for rapid estimation of distributed stator forces and three-dimensional effects of stator and/or rotor skew on the performance of the machine. The second contribution of this dissertation is the development of the design synthesis and optimization method based on a differential evolution algorithm. The approach relies on the developed finite element-based modeling method for electromagnetic analysis and is able to tackle large-scale multi-objective design problems using modest computational resources. Overall, computational time savings of up to two orders of magnitude are achievable, when compared to current and prevalent state-of-the-art methods. These computational savings allow one to expand the optimization problem to achieve more complex and comprehensive design objectives. The method is used in the design process of several interior permanent magnet industrial motors. The presented case studies demonstrate that the developed finite element-based approach practically eliminates the need for using less accurate analytical and lumped parameter equivalent circuit models for electric machine design optimization. The design process and experimental validation of the case-study machines are detailed in the dissertation.

Advanced Usage of Vehicle Sketch Pad for CFD-Based Conceptual Design

NASA Technical Reports Server (NTRS)

Ordaz, Irian; Li, Wu

2013-01-01

Conceptual design is the most fluid phase of aircraft design. It is important to be able to perform large scale design space exploration of candidate concepts that can achieve the design intent to avoid more costly configuration changes in later stages of design. This also means that conceptual design is highly dependent on the disciplinary analysis tools to capture the underlying physics accurately. The required level of analysis fidelity can vary greatly depending on the application. Vehicle Sketch Pad (VSP) allows the designer to easily construct aircraft concepts and make changes as the design matures. More recent development efforts have enabled VSP to bridge the gap to high-fidelity analysis disciplines such as computational fluid dynamics and structural modeling for finite element analysis. This paper focuses on the current state-of-the-art geometry modeling for the automated process of analysis and design of low-boom supersonic concepts using VSP and several capability-enhancing design tools.

Modeling and Analysis of Space Based Transceivers

NASA Technical Reports Server (NTRS)

Reinhart, Richard C.; Liebetreu, John; Moore, Michael S.; Price, Jeremy C.; Abbott, Ben

2005-01-01

This paper presents the tool chain, methodology, and initial results of a study to provide a thorough, objective, and quantitative analysis of the design alternatives for space Software Defined Radio (SDR) transceivers. The approach taken was to develop a set of models and tools for describing communications requirements, the algorithm resource requirements, the available hardware, and the alternative software architectures, and generate analysis data necessary to compare alternative designs. The Space Transceiver Analysis Tool (STAT) was developed to help users identify and select representative designs, calculate the analysis data, and perform a comparative analysis of the representative designs. The tool allows the design space to be searched quickly while permitting incremental refinement in regions of higher payoff.

Modeling and Analysis of Space Based Transceivers

NASA Technical Reports Server (NTRS)

Moore, Michael S.; Price, Jeremy C.; Abbott, Ben; Liebetreu, John; Reinhart, Richard C.; Kacpura, Thomas J.

2007-01-01

This paper presents the tool chain, methodology, and initial results of a study to provide a thorough, objective, and quantitative analysis of the design alternatives for space Software Defined Radio (SDR) transceivers. The approach taken was to develop a set of models and tools for describing communications requirements, the algorithm resource requirements, the available hardware, and the alternative software architectures, and generate analysis data necessary to compare alternative designs. The Space Transceiver Analysis Tool (STAT) was developed to help users identify and select representative designs, calculate the analysis data, and perform a comparative analysis of the representative designs. The tool allows the design space to be searched quickly while permitting incremental refinement in regions of higher payoff.

Probabilistic Scenario-based Seismic Risk Analysis for Critical Infrastructures Method and Application for a Nuclear Power Plant

NASA Astrophysics Data System (ADS)

Klügel, J.

2006-12-01

Deterministic scenario-based seismic hazard analysis has a long tradition in earthquake engineering for developing the design basis of critical infrastructures like dams, transport infrastructures, chemical plants and nuclear power plants. For many applications besides of the design of infrastructures it is of interest to assess the efficiency of the design measures taken. These applications require a method allowing to perform a meaningful quantitative risk analysis. A new method for a probabilistic scenario-based seismic risk analysis has been developed based on a probabilistic extension of proven deterministic methods like the MCE- methodology. The input data required for the method are entirely based on the information which is necessary to perform any meaningful seismic hazard analysis. The method is based on the probabilistic risk analysis approach common for applications in nuclear technology developed originally by Kaplan & Garrick (1981). It is based (1) on a classification of earthquake events into different size classes (by magnitude), (2) the evaluation of the frequency of occurrence of events, assigned to the different classes (frequency of initiating events, (3) the development of bounding critical scenarios assigned to each class based on the solution of an optimization problem and (4) in the evaluation of the conditional probability of exceedance of critical design parameters (vulnerability analysis). The advantage of the method in comparison with traditional PSHA consists in (1) its flexibility, allowing to use different probabilistic models for earthquake occurrence as well as to incorporate advanced physical models into the analysis, (2) in the mathematically consistent treatment of uncertainties, and (3) in the explicit consideration of the lifetime of the critical structure as a criterion to formulate different risk goals. The method was applied for the evaluation of the risk of production interruption losses of a nuclear power plant during its residual lifetime.

A multi-fidelity framework for physics based rotor blade simulation and optimization

NASA Astrophysics Data System (ADS)

Collins, Kyle Brian

New helicopter rotor designs are desired that offer increased efficiency, reduced vibration, and reduced noise. Rotor Designers in industry need methods that allow them to use the most accurate simulation tools available to search for these optimal designs. Computer based rotor analysis and optimization have been advanced by the development of industry standard codes known as "comprehensive" rotorcraft analysis tools. These tools typically use table look-up aerodynamics, simplified inflow models and perform aeroelastic analysis using Computational Structural Dynamics (CSD). Due to the simplified aerodynamics, most design studies are performed varying structural related design variables like sectional mass and stiffness. The optimization of shape related variables in forward flight using these tools is complicated and results are viewed with skepticism because rotor blade loads are not accurately predicted. The most accurate methods of rotor simulation utilize Computational Fluid Dynamics (CFD) but have historically been considered too computationally intensive to be used in computer based optimization, where numerous simulations are required. An approach is needed where high fidelity CFD rotor analysis can be utilized in a shape variable optimization problem with multiple objectives. Any approach should be capable of working in forward flight in addition to hover. An alternative is proposed and founded on the idea that efficient hybrid CFD methods of rotor analysis are ready to be used in preliminary design. In addition, the proposed approach recognizes the usefulness of lower fidelity physics based analysis and surrogate modeling. Together, they are used with high fidelity analysis in an intelligent process of surrogate model building of parameters in the high fidelity domain. Closing the loop between high and low fidelity analysis is a key aspect of the proposed approach. This is done by using information from higher fidelity analysis to improve predictions made with lower fidelity models. This thesis documents the development of automated low and high fidelity physics based rotor simulation frameworks. The low fidelity framework uses a comprehensive code with simplified aerodynamics. The high fidelity model uses a parallel processor capable CFD/CSD methodology. Both low and high fidelity frameworks include an aeroacoustic simulation for prediction of noise. A synergistic process is developed that uses both the low and high fidelity frameworks together to build approximate models of important high fidelity metrics as functions of certain design variables. To test the process, a 4-bladed hingeless rotor model is used as a baseline. The design variables investigated include tip geometry and spanwise twist distribution. Approximation models are built for metrics related to rotor efficiency and vibration using the results from 60+ high fidelity (CFD/CSD) experiments and 400+ low fidelity experiments. Optimization using the approximation models found the Pareto Frontier anchor points, or the design having maximum rotor efficiency and the design having minimum vibration. Various Pareto generation methods are used to find designs on the frontier between these two anchor designs. When tested in the high fidelity framework, the Pareto anchor designs are shown to be very good designs when compared with other designs from the high fidelity database. This provides evidence that the process proposed has merit. Ultimately, this process can be utilized by industry rotor designers with their existing tools to bring high fidelity analysis into the preliminary design stage of rotors. In conclusion, the methods developed and documented in this thesis have made several novel contributions. First, an automated high fidelity CFD based forward flight simulation framework has been built for use in preliminary design optimization. The framework was built around an integrated, parallel processor capable CFD/CSD/AA process. Second, a novel method of building approximate models of high fidelity parameters has been developed. The method uses a combination of low and high fidelity results and combines Design of Experiments, statistical effects analysis, and aspects of approximation model management. And third, the determination of rotor blade shape variables through optimization using CFD based analysis in forward flight has been performed. This was done using the high fidelity CFD/CSD/AA framework and method mentioned above. While the low and high fidelity predictions methods used in the work still have inaccuracies that can affect the absolute levels of the results, a framework has been successfully developed and demonstrated that allows for an efficient process to improve rotor blade designs in terms of a selected choice of objective function(s). Using engineering judgment, this methodology could be applied today to investigate opportunities to improve existing designs. With improvements in the low and high fidelity prediction components that will certainly occur, this framework could become a powerful tool for future rotorcraft design work. (Abstract shortened by UMI.)

Design and analysis of an underactuated anthropomorphic finger for upper limb prosthetics.

PubMed

Omarkulov, Nurdos; Telegenov, Kuat; Zeinullin, Maralbek; Begalinova, Ainur; Shintemirov, Almas

2015-01-01

This paper presents the design of a linkage based finger mechanism ensuring extended range of anthropomorphic gripping motions. The finger design is done using a path-point generation method based on geometrical dimensions and motion of a typical index human finger. Following the design description, and its kinematics analysis, the experimental evaluation of the finger gripping performance is presented using the finger 3D printed prototype. The finger underactuation is achieved by utilizing mechanical linkage system, consisting of two crossed four-bar linkage mechanisms. It is shown that the proposed finger design can be used to design a five-fingered anthropomorphic hand and has the potential for upper limb prostheses development.

Statistical Analyses of Femur Parameters for Designing Anatomical Plates.

PubMed

Wang, Lin; He, Kunjin; Chen, Zhengming

2016-01-01

Femur parameters are key prerequisites for scientifically designing anatomical plates. Meanwhile, individual differences in femurs present a challenge to design well-fitting anatomical plates. Therefore, to design anatomical plates more scientifically, analyses of femur parameters with statistical methods were performed in this study. The specific steps were as follows. First, taking eight anatomical femur parameters as variables, 100 femur samples were classified into three classes with factor analysis and Q-type cluster analysis. Second, based on the mean parameter values of the three classes of femurs, three sizes of average anatomical plates corresponding to the three classes of femurs were designed. Finally, based on Bayes discriminant analysis, a new femur could be assigned to the proper class. Thereafter, the average anatomical plate suitable for that new femur was selected from the three available sizes of plates. Experimental results showed that the classification of femurs was quite reasonable based on the anatomical aspects of the femurs. For instance, three sizes of condylar buttress plates were designed. Meanwhile, 20 new femurs are judged to which classes the femurs belong. Thereafter, suitable condylar buttress plates were determined and selected.

Design sensitivity analysis using EAL. Part 1: Conventional design parameters

NASA Technical Reports Server (NTRS)

Dopker, B.; Choi, Kyung K.; Lee, J.

1986-01-01

A numerical implementation of design sensitivity analysis of builtup structures is presented, using the versatility and convenience of an existing finite element structural analysis code and its database management system. The finite element code used in the implemenatation presented is the Engineering Analysis Language (EAL), which is based on a hybrid method of analysis. It was shown that design sensitivity computations can be carried out using the database management system of EAL, without writing a separate program and a separate database. Conventional (sizing) design parameters such as cross-sectional area of beams or thickness of plates and plane elastic solid components are considered. Compliance, displacement, and stress functionals are considered as performance criteria. The method presented is being extended to implement shape design sensitivity analysis using a domain method and a design component method.

A meta-analysis and review of holistic face processing.

PubMed

Richler, Jennifer J; Gauthier, Isabel

2014-09-01

The concept of holistic processing is a cornerstone of face recognition research, yet central questions related to holistic processing remain unanswered, and debates have thus far failed to reach a resolution despite accumulating empirical evidence. We argue that a considerable source of confusion in this literature stems from a methodological problem. Specifically, 2 measures of holistic processing based on the composite paradigm (complete design and partial design) are used in the literature, but they often lead to qualitatively different results. First, we present a comprehensive review of the work that directly compares the 2 designs, and which clearly favors the complete design over the partial design. Second, we report a meta-analysis of holistic face processing according to both designs and use this as further evidence for one design over the other. The meta-analysis effect size of holistic processing in the complete design is nearly 3 times that of the partial design. Effect sizes were not correlated between measures, consistent with the suggestion that they do not measure the same thing. Our meta-analysis also examines the correlation between conditions in the complete design of the composite task, and suggests that in an individual differences context, little is gained by including a misaligned baseline. Finally, we offer a comprehensive review of the state of knowledge about holistic processing based on evidence gathered from the measure we favor based on the 1st sections of our review-the complete design-and outline outstanding research questions in that new context. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Using extreme phenotype sampling to identify the rare causal variants of quantitative traits in association studies.

PubMed

Li, Dalin; Lewinger, Juan Pablo; Gauderman, William J; Murcray, Cassandra Elizabeth; Conti, David

2011-12-01

Variants identified in recent genome-wide association studies based on the common-disease common-variant hypothesis are far from fully explaining the hereditability of complex traits. Rare variants may, in part, explain some of the missing hereditability. Here, we explored the advantage of the extreme phenotype sampling in rare-variant analysis and refined this design framework for future large-scale association studies on quantitative traits. We first proposed a power calculation approach for a likelihood-based analysis method. We then used this approach to demonstrate the potential advantages of extreme phenotype sampling for rare variants. Next, we discussed how this design can influence future sequencing-based association studies from a cost-efficiency (with the phenotyping cost included) perspective. Moreover, we discussed the potential of a two-stage design with the extreme sample as the first stage and the remaining nonextreme subjects as the second stage. We demonstrated that this two-stage design is a cost-efficient alternative to the one-stage cross-sectional design or traditional two-stage design. We then discussed the analysis strategies for this extreme two-stage design and proposed a corresponding design optimization procedure. To address many practical concerns, for example measurement error or phenotypic heterogeneity at the very extremes, we examined an approach in which individuals with very extreme phenotypes are discarded. We demonstrated that even with a substantial proportion of these extreme individuals discarded, an extreme-based sampling can still be more efficient. Finally, we expanded the current analysis and design framework to accommodate the CMC approach where multiple rare-variants in the same gene region are analyzed jointly. © 2011 Wiley Periodicals, Inc.

Using Extreme Phenotype Sampling to Identify the Rare Causal Variants of Quantitative Traits in Association Studies

PubMed Central

Li, Dalin; Lewinger, Juan Pablo; Gauderman, William J.; Murcray, Cassandra Elizabeth; Conti, David

2014-01-01

Variants identified in recent genome-wide association studies based on the common-disease common-variant hypothesis are far from fully explaining the hereditability of complex traits. Rare variants may, in part, explain some of the missing hereditability. Here, we explored the advantage of the extreme phenotype sampling in rare-variant analysis and refined this design framework for future large-scale association studies on quantitative traits. We first proposed a power calculation approach for a likelihood-based analysis method. We then used this approach to demonstrate the potential advantages of extreme phenotype sampling for rare variants. Next, we discussed how this design can influence future sequencing-based association studies from a cost-efficiency (with the phenotyping cost included) perspective. Moreover, we discussed the potential of a two-stage design with the extreme sample as the first stage and the remaining nonextreme subjects as the second stage. We demonstrated that this two-stage design is a cost-efficient alternative to the one-stage cross-sectional design or traditional two-stage design. We then discussed the analysis strategies for this extreme two-stage design and proposed a corresponding design optimization procedure. To address many practical concerns, for example measurement error or phenotypic heterogeneity at the very extremes, we examined an approach in which individuals with very extreme phenotypes are discarded. We demonstrated that even with a substantial proportion of these extreme individuals discarded, an extreme-based sampling can still be more efficient. Finally, we expanded the current analysis and design framework to accommodate the CMC approach where multiple rare-variants in the same gene region are analyzed jointly. PMID:21922541

Computational approaches for drug discovery.

PubMed

Hung, Che-Lun; Chen, Chi-Chun

2014-09-01

Cellular proteins are the mediators of multiple organism functions being involved in physiological mechanisms and disease. By discovering lead compounds that affect the function of target proteins, the target diseases or physiological mechanisms can be modulated. Based on knowledge of the ligand-receptor interaction, the chemical structures of leads can be modified to improve efficacy, selectivity and reduce side effects. One rational drug design technology, which enables drug discovery based on knowledge of target structures, functional properties and mechanisms, is computer-aided drug design (CADD). The application of CADD can be cost-effective using experiments to compare predicted and actual drug activity, the results from which can used iteratively to improve compound properties. The two major CADD-based approaches are structure-based drug design, where protein structures are required, and ligand-based drug design, where ligand and ligand activities can be used to design compounds interacting with the protein structure. Approaches in structure-based drug design include docking, de novo design, fragment-based drug discovery and structure-based pharmacophore modeling. Approaches in ligand-based drug design include quantitative structure-affinity relationship and pharmacophore modeling based on ligand properties. Based on whether the structure of the receptor and its interaction with the ligand are known, different design strategies can be seed. After lead compounds are generated, the rule of five can be used to assess whether these have drug-like properties. Several quality validation methods, such as cost function analysis, Fisher's cross-validation analysis and goodness of hit test, can be used to estimate the metrics of different drug design strategies. To further improve CADD performance, multi-computers and graphics processing units may be applied to reduce costs. © 2014 Wiley Periodicals, Inc.

Design and Analysis of a Low Latency Deterministic Network MAC for Wireless Sensor Networks

PubMed Central

Sahoo, Prasan Kumar; Pattanaik, Sudhir Ranjan; Wu, Shih-Lin

2017-01-01

The IEEE 802.15.4e standard has four different superframe structures for different applications. Use of a low latency deterministic network (LLDN) superframe for the wireless sensor network is one of them, which can operate in a star topology. In this paper, a new channel access mechanism for IEEE 802.15.4e-based LLDN shared slots is proposed, and analytical models are designed based on this channel access mechanism. A prediction model is designed to estimate the possible number of retransmission slots based on the number of failed transmissions. Performance analysis in terms of data transmission reliability, delay, throughput and energy consumption are provided based on our proposed designs. Our designs are validated for simulation and analytical results, and it is observed that the simulation results well match with the analytical ones. Besides, our designs are compared with the IEEE 802.15.4 MAC mechanism, and it is shown that ours outperforms in terms of throughput, energy consumption, delay and reliability. PMID:28937632

Design and Analysis of a Low Latency Deterministic Network MAC for Wireless Sensor Networks.

PubMed

Sahoo, Prasan Kumar; Pattanaik, Sudhir Ranjan; Wu, Shih-Lin

2017-09-22

The IEEE 802.15.4e standard has four different superframe structures for different applications. Use of a low latency deterministic network (LLDN) superframe for the wireless sensor network is one of them, which can operate in a star topology. In this paper, a new channel access mechanism for IEEE 802.15.4e-based LLDN shared slots is proposed, and analytical models are designed based on this channel access mechanism. A prediction model is designed to estimate the possible number of retransmission slots based on the number of failed transmissions. Performance analysis in terms of data transmission reliability, delay, throughput and energy consumption are provided based on our proposed designs. Our designs are validated for simulation and analytical results, and it is observed that the simulation results well match with the analytical ones. Besides, our designs are compared with the IEEE 802.15.4 MAC mechanism, and it is shown that ours outperforms in terms of throughput, energy consumption, delay and reliability.

Automated Tetrahedral Mesh Generation for CFD Analysis of Aircraft in Conceptual Design

NASA Technical Reports Server (NTRS)

Ordaz, Irian; Li, Wu; Campbell, Richard L.

2014-01-01

The paper introduces an automation process of generating a tetrahedral mesh for computational fluid dynamics (CFD) analysis of aircraft configurations in early conceptual design. The method was developed for CFD-based sonic boom analysis of supersonic configurations, but can be applied to aerodynamic analysis of aircraft configurations in any flight regime.

TADS: A CFD-Based Turbomachinery Analysis and Design System with GUI: Methods and Results. 2.0

NASA Technical Reports Server (NTRS)

Koiro, M. J.; Myers, R. A.; Delaney, R. A.

1999-01-01

The primary objective of this study was the development of a Computational Fluid Dynamics (CFD) based turbomachinery airfoil analysis and design system, controlled by a Graphical User Interface (GUI). The computer codes resulting from this effort are referred to as TADS (Turbomachinery Analysis and Design System). This document is the Final Report describing the theoretical basis and analytical results from the TADS system developed under Task 10 of NASA Contract NAS3-27394, ADPAC System Coupling to Blade Analysis & Design System GUI, Phase II-Loss, Design and. Multi-stage Analysis. TADS couples a throughflow solver (ADPAC) with a quasi-3D blade-to-blade solver (RVCQ3D) or a 3-D solver with slip condition on the end walls (B2BADPAC) in an interactive package. Throughflow analysis and design capability was developed in ADPAC through the addition of blade force and blockage terms to the governing equations. A GUI was developed to simplify user input and automate the many tasks required to perform turbomachinery analysis and design. The coupling of the various programs was done in such a way that alternative solvers or grid generators could be easily incorporated into the TADS framework. Results of aerodynamic calculations using the TADS system are presented for a multistage compressor, a multistage turbine, two highly loaded fans, and several single stage compressor and turbine example cases.

Initial Multidisciplinary Design and Analysis Framework

NASA Technical Reports Server (NTRS)

Ozoroski, L. P.; Geiselhart, K. A.; Padula, S. L.; Li, W.; Olson, E. D.; Campbell, R. L.; Shields, E. W.; Berton, J. J.; Gray, J. S.; Jones, S. M.;

Multi-country health surveys: are the analyses misleading?

PubMed

Masood, Mohd; Reidpath, Daniel D

2014-05-01

The aim of this paper was to review the types of approaches currently utilized in the analysis of multi-country survey data, specifically focusing on design and modeling issues with a focus on analyses of significant multi-country surveys published in 2010. A systematic search strategy was used to identify the 10 multi-country surveys and the articles published from them in 2010. The surveys were selected to reflect diverse topics and foci; and provide an insight into analytic approaches across research themes. The search identified 159 articles appropriate for full text review and data extraction. The analyses adopted in the multi-country surveys can be broadly classified as: univariate/bivariate analyses, and multivariate/multivariable analyses. Multivariate/multivariable analyses may be further divided into design- and model-based analyses. Of the 159 articles reviewed, 129 articles used model-based analysis, 30 articles used design-based analyses. Similar patterns could be seen in all the individual surveys. While there is general agreement among survey statisticians that complex surveys are most appropriately analyzed using design-based analyses, most researchers continued to use the more common model-based approaches. Recent developments in design-based multi-level analysis may be one approach to include all the survey design characteristics. This is a relatively new area, however, and there remains statistical, as well as applied analytic research required. An important limitation of this study relates to the selection of the surveys used and the choice of year for the analysis, i.e., year 2010 only. There is, however, no strong reason to believe that analytic strategies have changed radically in the past few years, and 2010 provides a credible snapshot of current practice.

Mapping remote and multidisciplinary learning barriers: lessons from challenge-based innovation at CERN

NASA Astrophysics Data System (ADS)

Jensen, Matilde Bisballe; Utriainen, Tuuli Maria; Steinert, Martin

2018-01-01

This paper presents the experienced difficulties of students participating in the multidisciplinary, remote collaborating engineering design course challenge-based innovation at CERN. This is with the aim to identify learning barriers and improve future learning experiences. We statistically analyse the rated differences between distinct design activities, educational background and remote vs. co-located collaboration. The analysis is based on a quantitative and qualitative questionnaire (N = 37). Our analysis found significant ranking differences between remote and co-located activities. This questions whether the remote factor might be a barrier for the originally intended learning goals. Further a correlation between analytical and converging design phases was identified. Hence, future facilitators are suggested to help students in the transition from one design phase to the next rather than only teaching methods in the individual design phases. Finally, we discuss how educators address the identified learning barriers when designing future courses including multidisciplinary or remote collaboration.

Design of microcontroller-based EMG and the analysis of EMG signals.

PubMed

Güler, Nihal Fatma; Hardalaç, Firat

2002-04-01

In this work, a microcontroller-based EMG designed and tested on 40 patients. When the patients are in rest, the fast Fourier transform (FFT) analysis was applied to EMG signals recorded from right leg peroneal region. The histograms are constructed from the results of the FFT analysis. The analysis results shows that the amplitude of fibrillation potential of the muscle fiber of 30 patients measured from peroneal region is low and the duration is short. This is the reason why the motor nerves degenerated and 10 patients were found to be healthy.

Integration of Engine, Plume, and CFD Analyses in Conceptual Design of Low-Boom Supersonic Aircraft

NASA Technical Reports Server (NTRS)

Li, Wu; Campbell, Richard; Geiselhart, Karl; Shields, Elwood; Nayani, Sudheer; Shenoy, Rajiv

2009-01-01

This paper documents an integration of engine, plume, and computational fluid dynamics (CFD) analyses in the conceptual design of low-boom supersonic aircraft, using a variable fidelity approach. In particular, the Numerical Propulsion Simulation System (NPSS) is used for propulsion system cycle analysis and nacelle outer mold line definition, and a low-fidelity plume model is developed for plume shape prediction based on NPSS engine data and nacelle geometry. This model provides a capability for the conceptual design of low-boom supersonic aircraft that accounts for plume effects. Then a newly developed process for automated CFD analysis is presented for CFD-based plume and boom analyses of the conceptual geometry. Five test cases are used to demonstrate the integrated engine, plume, and CFD analysis process based on a variable fidelity approach, as well as the feasibility of the automated CFD plume and boom analysis capability.

Finite Element Analysis (FEA) in Design and Production.

ERIC Educational Resources Information Center

Waggoner, Todd C.; And Others

1995-01-01

Finite element analysis (FEA) enables industrial designers to analyze complex components by dividing them into smaller elements, then assessing stress and strain characteristics. Traditionally mainframe based, FEA is being increasingly used in microcomputers. (SK)

Computer Graphics-aided systems analysis: application to well completion design

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

Detamore, J.E.; Sarma, M.P.

1985-03-01

The development of an engineering tool (in the form of a computer model) for solving design and analysis problems related with oil and gas well production operations is discussed. The development of the method is based on integrating the concepts of ''Systems Analysis'' with the techniques of ''Computer Graphics''. The concepts behind the method are very general in nature. This paper, however, illustrates the application of the method in solving gas well completion design problems. The use of the method will save time and improve the efficiency of such design and analysis problems. The method can be extended to othermore » design and analysis aspects of oil and gas wells.« less

Rocket Design for the Future

NASA Technical Reports Server (NTRS)

Follett, William W.; Rajagopal, Raj

2001-01-01

The focus of the AA MDO team is to reduce product development cost through the capture and automation of best design and analysis practices and through increasing the availability of low-cost, high-fidelity analysis. Implementation of robust designs reduces costs associated with the Test-Fall-Fix cycle. RD is currently focusing on several technologies to improve the design process, including optimization and robust design, expert and rule-based systems, and collaborative technologies.

The NASA Monographs on Shell Stability Design Recommendations: A Review and Suggested Improvements

NASA Technical Reports Server (NTRS)

Nemeth, Michael P.; Starnes, James H., Jr.

1998-01-01

A summary of existing NASA design criteria monographs for the design of buckling-resistant thin-shell structures is presented. Subsequent improvements in the analysis for nonlinear shell response are reviewed, and current issues in shell stability analysis are discussed. Examples of nonlinear shell responses that are not included in the existing shell design monographs are presented, and an approach for including reliability based analysis procedures in the shell design process is discussed. Suggestions for conducting future shell experiments are presented, and proposed improvements to the NASA shell design criteria monographs are discussed.

The NASA Monographs on Shell Stability Design Recommendations: A Review and Suggested Improvements

NASA Technical Reports Server (NTRS)

Nemeth, Michael P.; Starnes, James H., Jr.

1998-01-01

A summary of the existing NASA design criteria monographs for the design of buckling-resistant thin-shell structures is presented. Subsequent improvements in the analysis for nonlinear shell response are reviewed, and current issues in shell stability analysis are discussed. Examples of nonlinear shell responses that are not included in the existing shell design monographs are presented, and an approach for including reliability-based analysis procedures in the shell design process is discussed. Suggestions for conducting future shell experiments are presented, and proposed improvements to the NASA shell design criteria monographs are discussed.

The NASA/industry Design Analysis Methods for Vibrations (DAMVIBS) Program: A government overview

NASA Technical Reports Server (NTRS)

Kvaternik, Raymond G.

1992-01-01

LaRC, under the Design Analysis Methods for Vibrations (DAMVIBS) Program, set out in 1984 to establish the technology base needed by the rotorcraft industry for developing an advanced finite-element-based dynamics design analysis capability for vibrations. Considerable work was performed by the industry participants in the program since that time. Because the DAMVIBS Program is being phased out, a government/industry assessment of the program was made to identify those accomplishments and contributions which may be ascribed to the program. The purpose is to provide an overview of the program and its accomplishments and contributions from the perspective of the government sponsoring organization.

Pattern database applications from design to manufacturing

NASA Astrophysics Data System (ADS)

Zhuang, Linda; Zhu, Annie; Zhang, Yifan; Sweis, Jason; Lai, Ya-Chieh

2017-03-01

Pattern-based approaches are becoming more common and popular as the industry moves to advanced technology nodes. At the beginning of a new technology node, a library of process weak point patterns for physical and electrical verification are starting to build up and used to prevent known hotspots from re-occurring on new designs. Then the pattern set is expanded to create test keys for process development in order to verify the manufacturing capability and precheck new tape-out designs for any potential yield detractors. With the database growing, the adoption of pattern-based approaches has expanded from design flows to technology development and then needed for mass-production purposes. This paper will present the complete downstream working flows of a design pattern database(PDB). This pattern-based data analysis flow covers different applications across different functional teams from generating enhancement kits to improving design manufacturability, populating new testing design data based on previous-learning, generating analysis data to improve mass-production efficiency and manufacturing equipment in-line control to check machine status consistency across different fab sites.

Multivariate Analysis, Retrieval, and Storage System (MARS). Volume 1: MARS System and Analysis Techniques

NASA Technical Reports Server (NTRS)

Hague, D. S.; Vanderberg, J. D.; Woodbury, N. W.

1974-01-01

A method for rapidly examining the probable applicability of weight estimating formulae to a specific aerospace vehicle design is presented. The Multivariate Analysis Retrieval and Storage System (MARS) is comprised of three computer programs which sequentially operate on the weight and geometry characteristics of past aerospace vehicles designs. Weight and geometric characteristics are stored in a set of data bases which are fully computerized. Additional data bases are readily added to the MARS system and/or the existing data bases may be easily expanded to include additional vehicles or vehicle characteristics.

Development and Validation of a Web-Based Module to Teach Metacognitive Learning Strategies to Students in Higher Education

ERIC Educational Resources Information Center

Singh, Oma B.

2009-01-01

This study used a design based-research (DBR) methodology to examine how an Instructional Systematic Design (ISD) process such as ADDIE (Analysis, Design, Development, Implementation, Evaluation) can be employed to develop a web-based module to teach metacognitive learning strategies to students in higher education. The goal of the study was…

On-Line Analysis of Southern FIA Data

Treesearch

Michael P. Spinney; Paul C. Van Deusen; Francis A. Roesch

2006-01-01

The Southern On-Line Estimator (SOLE) is a web-based FIA database analysis tool designed with an emphasis on modularity. The Java-based user interface is simple and intuitive to use and the R-based analysis engine is fast and stable. Each component of the program (data retrieval, statistical analysis and output) can be individually modified to accommodate major...

Data engineering systems: Computerized modeling and data bank capabilities for engineering analysis

NASA Technical Reports Server (NTRS)

Kopp, H.; Trettau, R.; Zolotar, B.

1984-01-01

The Data Engineering System (DES) is a computer-based system that organizes technical data and provides automated mechanisms for storage, retrieval, and engineering analysis. The DES combines the benefits of a structured data base system with automated links to large-scale analysis codes. While the DES provides the user with many of the capabilities of a computer-aided design (CAD) system, the systems are actually quite different in several respects. A typical CAD system emphasizes interactive graphics capabilities and organizes data in a manner that optimizes these graphics. On the other hand, the DES is a computer-aided engineering system intended for the engineer who must operationally understand an existing or planned design or who desires to carry out additional technical analysis based on a particular design. The DES emphasizes data retrieval in a form that not only provides the engineer access to search and display the data but also links the data automatically with the computer analysis codes.

[Development and application of a web-based expert system using artificial intelligence for management of mental health by Korean emigrants].

PubMed

Bae, Jeongyee

2013-04-01

The purpose of this project was to develop an international web-based expert system using principals of artificial intelligence and user-centered design for management of mental health by Korean emigrants. Using this system, anyone can access the system via computer access to the web. Our design process utilized principles of user-centered design with 4 phases: needs assessment, analysis, design/development/testing, and application release. A survey was done with 3,235 Korean emigrants. Focus group interviews were also conducted. Survey and analysis results guided the design of the web-based expert system. With this system, anyone can check their mental health status by themselves using a personal computer. The system analyzes facts based on answers to automated questions, and suggests solutions accordingly. A history tracking mechanism enables monitoring and future analysis. In addition, this system will include intervention programs to promote mental health status. This system is interactive and accessible to anyone in the world. It is expected that this management system will contribute to Korean emigrants' mental health promotion and allow researchers and professionals to share information on mental health.

Program Aids Design Of Fluid-Circulating Systems

NASA Technical Reports Server (NTRS)

Bacskay, Allen; Dalee, Robert

1992-01-01

Computer Aided Systems Engineering and Analysis (CASE/A) program is interactive software tool for trade study and analysis, designed to increase productivity during all phases of systems engineering. Graphics-based command-driven software package provides user-friendly computing environment in which engineer analyzes performance and interface characteristics of ECLS/ATC system. Useful during all phases of spacecraft-design program, from initial conceptual design trade studies to actual flight, including pre-flight prediction and in-flight analysis of anomalies. Written in FORTRAN 77.

Study on Optimum Design of Multi-Pole Interior Permanent Magnet Motor with Concentrated Windings

NASA Astrophysics Data System (ADS)

Kano, Yoshiaki; Kosaka, Takashi; Matsui, Nobuyuki

Interior Permanent Magnet Synchronous Motors (IPMSM) have been found in many applications because of their high-power density and high-efficiency. The existence of a complex magnetic circuit, however, makes the design of this machine quite complicated. Although FEM is commonly used in the IPMSM design, one of disadvantages is long CPU times. This paper presents a simple non-linear magnetic analysis for a multi-pole IPMSM as a preliminary design tool of FEM. The proposed analysis consists of the geometric-flux-tube-based equivalent-magnetic-circuit model. The model includes saturable permeances taking into account the local magnetic saturation in the core. As a result, the proposed analysis is capable of calculating the flux distribution and the torque characteristics in the presence of magnetic saturation. The effectiveness of the proposed analysis is verified by comparing with FEM in terms of the analytical accuracy and the computation time for two IPMSMs with different specifications. After verification, the proposed analysis-based optimum design is examined, by which the minimization of motor volume is realized while satisfying the necessary maximum torque for target applications.

GSP: A web-based platform for designing genome-specific primers in polyploids

USDA-ARS?s Scientific Manuscript database

The sequences among subgenomes in a polyploid species have high similarity. This makes difficult to design genome-specific primers for sequence analysis. We present a web-based platform named GSP for designing genome-specific primers to distinguish subgenome sequences in the polyploid genome backgr...

Interchange Safety Analysis Tool (ISAT) : user manual

DOT National Transportation Integrated Search

2007-06-01

This User Manual describes the usage and operation of the spreadsheet-based Interchange Safety Analysis Tool (ISAT). ISAT provides design and safety engineers with an automated tool for assessing the safety effects of geometric design and traffic con...

Sensitivity analysis, approximate analysis, and design optimization for internal and external viscous flows

NASA Technical Reports Server (NTRS)

Taylor, Arthur C., III; Hou, Gene W.; Korivi, Vamshi M.

1991-01-01

A gradient-based design optimization strategy for practical aerodynamic design applications is presented, which uses the 2D thin-layer Navier-Stokes equations. The strategy is based on the classic idea of constructing different modules for performing the major tasks such as function evaluation, function approximation and sensitivity analysis, mesh regeneration, and grid sensitivity analysis, all driven and controlled by a general-purpose design optimization program. The accuracy of aerodynamic shape sensitivity derivatives is validated on two viscous test problems: internal flow through a double-throat nozzle and external flow over a NACA 4-digit airfoil. A significant improvement in aerodynamic performance has been achieved in both cases. Particular attention is given to a consistent treatment of the boundary conditions in the calculation of the aerodynamic sensitivity derivatives for the classic problems of external flow over an isolated lifting airfoil on 'C' or 'O' meshes.

CAPRI (Computational Analysis PRogramming Interface): A Solid Modeling Based Infra-Structure for Engineering Analysis and Design Simulations

NASA Technical Reports Server (NTRS)

Haimes, Robert; Follen, Gregory J.

1998-01-01

CAPRI is a CAD-vendor neutral application programming interface designed for the construction of analysis and design systems. By allowing access to the geometry from within all modules (grid generators, solvers and post-processors) such tasks as meshing on the actual surfaces, node enrichment by solvers and defining which mesh faces are boundaries (for the solver and visualization system) become simpler. The overall reliance on file 'standards' is minimized. This 'Geometry Centric' approach makes multi-physics (multi-disciplinary) analysis codes much easier to build. By using the shared (coupled) surface as the foundation, CAPRI provides a single call to interpolate grid-node based data from the surface discretization in one volume to another. Finally, design systems are possible where the results can be brought back into the CAD system (and therefore manufactured) because all geometry construction and modification are performed using the CAD system's geometry kernel.

RELAP-7 Software Verification and Validation Plan

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

Smith, Curtis L.; Choi, Yong-Joon; Zou, Ling

This INL plan comprehensively describes the software for RELAP-7 and documents the software, interface, and software design requirements for the application. The plan also describes the testing-based software verification and validation (SV&V) process—a set of specially designed software models used to test RELAP-7. The RELAP-7 (Reactor Excursion and Leak Analysis Program) code is a nuclear reactor system safety analysis code being developed at Idaho National Laboratory (INL). The code is based on the INL’s modern scientific software development framework – MOOSE (Multi-Physics Object-Oriented Simulation Environment). The overall design goal of RELAP-7 is to take advantage of the previous thirty yearsmore » of advancements in computer architecture, software design, numerical integration methods, and physical models. The end result will be a reactor systems analysis capability that retains and improves upon RELAP5’s capability and extends the analysis capability for all reactor system simulation scenarios.« less

Use of Model-Based Design Methods for Enhancing Resiliency Analysis of Unmanned Aerial Vehicles

NASA Astrophysics Data System (ADS)

Knox, Lenora A.

The most common traditional non-functional requirement analysis is reliability. With systems becoming more complex, networked, and adaptive to environmental uncertainties, system resiliency has recently become the non-functional requirement analysis of choice. Analysis of system resiliency has challenges; which include, defining resilience for domain areas, identifying resilience metrics, determining resilience modeling strategies, and understanding how to best integrate the concepts of risk and reliability into resiliency. Formal methods that integrate all of these concepts do not currently exist in specific domain areas. Leveraging RAMSoS, a model-based reliability analysis methodology for Systems of Systems (SoS), we propose an extension that accounts for resiliency analysis through evaluation of mission performance, risk, and cost using multi-criteria decision-making (MCDM) modeling and design trade study variability modeling evaluation techniques. This proposed methodology, coined RAMSoS-RESIL, is applied to a case study in the multi-agent unmanned aerial vehicle (UAV) domain to investigate the potential benefits of a mission architecture where functionality to complete a mission is disseminated across multiple UAVs (distributed) opposed to being contained in a single UAV (monolithic). The case study based research demonstrates proof of concept for the proposed model-based technique and provides sufficient preliminary evidence to conclude which architectural design (distributed vs. monolithic) is most resilient based on insight into mission resilience performance, risk, and cost in addition to the traditional analysis of reliability.

Professional Development for Mathematics Teachers: Using Task Design and Analysis

ERIC Educational Resources Information Center

Lee, Hea-Jin; Özgün-Koca, S. Asli

2016-01-01

This study is based on a Task Design and Analysis activity from a year-long professional development program. The activity was designed to increase teacher growth in several areas, including knowledge of mathematics, understanding of students' cognitive activity, knowledge of good questions, and ability to develop and improve high quality tasks.…

Integrating Model-Based Verification into Software Design Education

ERIC Educational Resources Information Center

Yilmaz, Levent; Wang, Shuo

2005-01-01

Proper design analysis is indispensable to assure quality and reduce emergent costs due to faulty software. Teaching proper design verification skills early during pedagogical development is crucial, as such analysis is the only tractable way of resolving software problems early when they are easy to fix. The premise of the presented strategy is…

Surrogate-based Analysis and Optimization

NASA Technical Reports Server (NTRS)

Queipo, Nestor V.; Haftka, Raphael T.; Shyy, Wei; Goel, Tushar; Vaidyanathan, Raj; Tucker, P. Kevin

2005-01-01

A major challenge to the successful full-scale development of modem aerospace systems is to address competing objectives such as improved performance, reduced costs, and enhanced safety. Accurate, high-fidelity models are typically time consuming and computationally expensive. Furthermore, informed decisions should be made with an understanding of the impact (global sensitivity) of the design variables on the different objectives. In this context, the so-called surrogate-based approach for analysis and optimization can play a very valuable role. The surrogates are constructed using data drawn from high-fidelity models, and provide fast approximations of the objectives and constraints at new design points, thereby making sensitivity and optimization studies feasible. This paper provides a comprehensive discussion of the fundamental issues that arise in surrogate-based analysis and optimization (SBAO), highlighting concepts, methods, techniques, as well as practical implications. The issues addressed include the selection of the loss function and regularization criteria for constructing the surrogates, design of experiments, surrogate selection and construction, sensitivity analysis, convergence, and optimization. The multi-objective optimal design of a liquid rocket injector is presented to highlight the state of the art and to help guide future efforts.

Process-based organization design and hospital efficiency.

PubMed

Vera, Antonio; Kuntz, Ludwig

2007-01-01

The central idea of process-based organization design is that organizing a firm around core business processes leads to cost reductions and quality improvements. We investigated theoretically and empirically whether the implementation of a process-based organization design is advisable in hospitals. The data came from a database compiled by the Statistical Office of the German federal state of Rheinland-Pfalz and from a written questionnaire, which was sent to the chief executive officers (CEOs) of all 92 hospitals in this federal state. We used data envelopment analysis (DEA) to measure hospital efficiency, and factor analysis and regression analysis to test our hypothesis. Our principal finding is that a high degree of process-based organization has a moderate but significant positive effect on the efficiency of hospitals. The main implication is that hospitals should implement a process-based organization to improve their efficiency. However, to actually achieve positive effects on efficiency, it is of paramount importance to observe some implementation rules, in particular to mobilize physician participation and to create an adequate organizational culture.

Simplified analytical model and balanced design approach for light-weight wood-based structural panel in bending

Treesearch

Jinghao Li; John F. Hunt; Shaoqin Gong; Zhiyong Cai

2016-01-01

This paper presents a simplified analytical model and balanced design approach for modeling lightweight wood-based structural panels in bending. Because many design parameters are required to input for the model of finite element analysis (FEA) during the preliminary design process and optimization, the equivalent method was developed to analyze the mechanical...

Automating Structural Analysis of Spacecraft Vehicles

NASA Technical Reports Server (NTRS)

Hrinda, Glenn A.

2004-01-01

A major effort within NASA's vehicle analysis discipline has been to automate structural analysis and sizing optimization during conceptual design studies of advanced spacecraft. Traditional spacecraft structural sizing has involved detailed finite element analysis (FEA) requiring large degree-of-freedom (DOF) finite element models (FEM). Creation and analysis of these models can be time consuming and limit model size during conceptual designs. The goal is to find an optimal design that meets the mission requirements but produces the lightest structure. A structural sizing tool called HyperSizer has been successfully used in the conceptual design phase of a reusable launch vehicle and planetary exploration spacecraft. The program couples with FEA to enable system level performance assessments and weight predictions including design optimization of material selections and sizing of spacecraft members. The software's analysis capabilities are based on established aerospace structural methods for strength, stability and stiffness that produce adequately sized members and reliable structural weight estimates. The software also helps to identify potential structural deficiencies early in the conceptual design so changes can be made without wasted time. HyperSizer's automated analysis and sizing optimization increases productivity and brings standardization to a systems study. These benefits will be illustrated in examining two different types of conceptual spacecraft designed using the software. A hypersonic air breathing, single stage to orbit (SSTO), reusable launch vehicle (RLV) will be highlighted as well as an aeroshell for a planetary exploration vehicle used for aerocapture at Mars. By showing the two different types of vehicles, the software's flexibility will be demonstrated with an emphasis on reducing aeroshell structural weight. Member sizes, concepts and material selections will be discussed as well as analysis methods used in optimizing the structure. Analysis based on the HyperSizer structural sizing software will be discussed. Design trades required to optimize structural weight will be presented.

Assessing the 'system' in safe systems-based road designs: using cognitive work analysis to evaluate intersection designs.

PubMed

Cornelissen, M; Salmon, P M; Stanton, N A; McClure, R

2015-01-01

While a safe systems approach has long been acknowledged as the underlying philosophy of contemporary road safety strategies, systemic applications are sparse. This article argues that systems-based methods from the discipline of Ergonomics have a key role to play in road transport design and evaluation. To demonstrate, the Cognitive Work Analysis framework was used to evaluate two road designs - a traditional Melbourne intersection and a cut-through design for future intersections based on road safety safe systems principles. The results demonstrate that, although the cut-through intersection appears different in layout from the traditional intersection, system constraints are not markedly different. Furthermore, the analyses demonstrated that redistribution of constraints in the cut-through intersection resulted in emergent behaviour, which was not anticipated and could prove problematic. Further, based on the lack of understanding of emergent behaviour, similar design induced problems are apparent across both intersections. Specifically, incompatibilities between infrastructure, vehicles and different road users were not dealt with by the proposed design changes. The importance of applying systems methods in the design and evaluation of road transport systems is discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

TADS: A CFD-based turbomachinery and analysis design system with GUI. Volume 1: Method and results

NASA Technical Reports Server (NTRS)

Topp, D. A.; Myers, R. A.; Delaney, R. A.

1995-01-01

The primary objective of this study was the development of a CFD (Computational Fluid Dynamics) based turbomachinery airfoil analysis and design system, controlled by a GUI (Graphical User Interface). The computer codes resulting from this effort are referred to as TADS (Turbomachinery Analysis and Design System). This document is the Final Report describing the theoretical basis and analytical results from the TADS system, developed under Task 18 of NASA Contract NAS3-25950, ADPAC System Coupling to Blade Analysis & Design System GUI. TADS couples a throughflow solver (ADPAC) with a quasi-3D blade-to-blade solver (RVCQ3D) in an interactive package. Throughflow analysis capability was developed in ADPAC through the addition of blade force and blockage terms to the governing equations. A GUI was developed to simplify user input and automate the many tasks required to perform turbomachinery analysis and design. The coupling of the various programs was done in such a way that alternative solvers or grid generators could be easily incorporated into the TADS framework. Results of aerodynamic calculations using the TADS system are presented for a highly loaded fan, a compressor stator, a low speed turbine blade and a transonic turbine vane.

An Investigation into a Gear-Based Knee Joint Designed for Lower Limb Prosthesis.

PubMed

Bhuiyan, M S H; Choudhury, I A; Dahari, M; Nukman, Y; Dawal, S Z

2017-01-01

A gear-based knee joint is designed to improve the performance of mechanical-type above-knee prostheses. The gear set with the help of some bracing, and bracket arrangement, is used to enable the prosthesis to follow the residual limb movement. The motion analysis and finite-element analysis (FEA) of knee joint components are carried out to assess the feasibility of the design. The maximum stress of 29.74 MPa and maximum strain of 2.393e-004 are obtained in the gear, whereas the maximum displacement of 7.975 mm occurred in the stopper of the knee arrangement. The factor of safety of 3.5 obtained from the FE analysis indicated no possibility of design failure. The results obtained from the FE analysis are then compared with the real data obtained from the literature for a similar subject. The pattern of motion analysis results has shown a great resemblance with the gait cycle of a healthy biological limb.

An Investigation into a Gear-Based Knee Joint Designed for Lower Limb Prosthesis

PubMed Central

2017-01-01

A gear-based knee joint is designed to improve the performance of mechanical-type above-knee prostheses. The gear set with the help of some bracing, and bracket arrangement, is used to enable the prosthesis to follow the residual limb movement. The motion analysis and finite-element analysis (FEA) of knee joint components are carried out to assess the feasibility of the design. The maximum stress of 29.74 MPa and maximum strain of 2.393e−004 are obtained in the gear, whereas the maximum displacement of 7.975 mm occurred in the stopper of the knee arrangement. The factor of safety of 3.5 obtained from the FE analysis indicated no possibility of design failure. The results obtained from the FE analysis are then compared with the real data obtained from the literature for a similar subject. The pattern of motion analysis results has shown a great resemblance with the gait cycle of a healthy biological limb. PMID:28584518

Using task analysis to improve the requirements elicitation in health information system.

PubMed

Teixeira, Leonor; Ferreira, Carlos; Santos, Beatriz Sousa

2007-01-01

This paper describes the application of task analysis within the design process of a Web-based information system for managing clinical information in hemophilia care, in order to improve the requirements elicitation and, consequently, to validate the domain model obtained in a previous phase of the design process (system analysis). The use of task analysis in this case proved to be a practical and efficient way to improve the requirements engineering process by involving users in the design process.

Thermal design, rating and second law analysis of shell and tube condensers based on Taguchi optimization for waste heat recovery based thermal desalination plants

NASA Astrophysics Data System (ADS)

Chandrakanth, Balaji; Venkatesan, G; Prakash Kumar, L. S. S; Jalihal, Purnima; Iniyan, S

2018-03-01

The present work discusses the design and selection of a shell and tube condenser used in Low Temperature Thermal Desalination (LTTD). To optimize the key geometrical and process parameters of the condenser with multiple parameters and levels, a design of an experiment approach using Taguchi method was chosen. An orthogonal array (OA) of 25 designs was selected for this study. The condenser was designed, analysed using HTRI software and the heat transfer area with respective tube side pressure drop were computed using the same, as these two objective functions determine the capital and running cost of the condenser. There was a complex trade off between the heat transfer area and pressure drop in the analysis, however second law analysis was worked out for determining the optimal heat transfer area vs pressure drop for condensing the required heat load.

Design and analysis of tubular permanent magnet linear generator for small-scale wave energy converter

NASA Astrophysics Data System (ADS)

Kim, Jeong-Man; Koo, Min-Mo; Jeong, Jae-Hoon; Hong, Keyyong; Cho, Il-Hyoung; Choi, Jang-Young

2017-05-01

This paper reports the design and analysis of a tubular permanent magnet linear generator (TPMLG) for a small-scale wave-energy converter. The analytical field computation is performed by applying a magnetic vector potential and a 2-D analytical model to determine design parameters. Based on analytical solutions, parametric analysis is performed to meet the design specifications of a wave-energy converter (WEC). Then, 2-D FEA is employed to validate the analytical method. Finally, the experimental result confirms the predictions of the analytical and finite element analysis (FEA) methods under regular and irregular wave conditions.

A Step-by-Step Design Methodology for a Base Case Vanadium Redox-Flow Battery

ERIC Educational Resources Information Center

Moore, Mark; Counce, Robert M.; Watson, Jack S.; Zawodzinski, Thomas A.; Kamath, Haresh

2012-01-01

The purpose of this work is to develop an evolutionary procedure to be used by Chemical Engineering students for the base-case design of a Vanadium Redox-Flow Battery. The design methodology is based on the work of Douglas (1985) and provides a profitability analysis at each decision level so that more profitable alternatives and directions can be…

Space station system analysis study. Part 3: Documentation. Volume 2: Technical report. [structural design and construction

NASA Technical Reports Server (NTRS)

1977-01-01

An analysis of construction operation is presented as well as power system sizing requirements. Mission hardware requirements are reviewed in detail. Space construction base and design configurations are also examined.

The wave-based substructuring approach for the efficient description of interface dynamics in substructuring

NASA Astrophysics Data System (ADS)

Donders, S.; Pluymers, B.; Ragnarsson, P.; Hadjit, R.; Desmet, W.

2010-04-01

In the vehicle design process, design decisions are more and more based on virtual prototypes. Due to competitive and regulatory pressure, vehicle manufacturers are forced to improve product quality, to reduce time-to-market and to launch an increasing number of design variants on the global market. To speed up the design iteration process, substructuring and component mode synthesis (CMS) methods are commonly used, involving the analysis of substructure models and the synthesis of the substructure analysis results. Substructuring and CMS enable efficient decentralized collaboration across departments and allow to benefit from the availability of parallel computing environments. However, traditional CMS methods become prohibitively inefficient when substructures are coupled along large interfaces, i.e. with a large number of degrees of freedom (DOFs) at the interface between substructures. The reason is that the analysis of substructures involves the calculation of a number of enrichment vectors, one for each interface degree of freedom (DOF). Since large interfaces are common in vehicles (e.g. the continuous line connections to connect the body with the windshield, roof or floor), this interface bottleneck poses a clear limitation in the vehicle noise, vibration and harshness (NVH) design process. Therefore there is a need to describe the interface dynamics more efficiently. This paper presents a wave-based substructuring (WBS) approach, which allows reducing the interface representation between substructures in an assembly by expressing the interface DOFs in terms of a limited set of basis functions ("waves"). As the number of basis functions can be much lower than the number of interface DOFs, this greatly facilitates the substructure analysis procedure and results in faster design predictions. The waves are calculated once from a full nominal assembly analysis, but these nominal waves can be re-used for the assembly of modified components. The WBS approach thus enables efficient structural modification predictions of the global modes, so that efficient vibro-acoustic design modification, optimization and robust design become possible. The results show that wave-based substructuring offers a clear benefit for vehicle design modifications, by improving both the speed of component reduction processes and the efficiency and accuracy of design iteration predictions, as compared to conventional substructuring approaches.

Adaptive Modeling, Engineering Analysis and Design of Advanced Aerospace Vehicles

NASA Technical Reports Server (NTRS)

Mukhopadhyay, Vivek; Hsu, Su-Yuen; Mason, Brian H.; Hicks, Mike D.; Jones, William T.; Sleight, David W.; Chun, Julio; Spangler, Jan L.; Kamhawi, Hilmi; Dahl, Jorgen L.

2006-01-01

This paper describes initial progress towards the development and enhancement of a set of software tools for rapid adaptive modeling, and conceptual design of advanced aerospace vehicle concepts. With demanding structural and aerodynamic performance requirements, these high fidelity geometry based modeling tools are essential for rapid and accurate engineering analysis at the early concept development stage. This adaptive modeling tool was used for generating vehicle parametric geometry, outer mold line and detailed internal structural layout of wing, fuselage, skin, spars, ribs, control surfaces, frames, bulkheads, floors, etc., that facilitated rapid finite element analysis, sizing study and weight optimization. The high quality outer mold line enabled rapid aerodynamic analysis in order to provide reliable design data at critical flight conditions. Example application for structural design of a conventional aircraft and a high altitude long endurance vehicle configuration are presented. This work was performed under the Conceptual Design Shop sub-project within the Efficient Aerodynamic Shape and Integration project, under the former Vehicle Systems Program. The project objective was to design and assess unconventional atmospheric vehicle concepts efficiently and confidently. The implementation may also dramatically facilitate physics-based systems analysis for the NASA Fundamental Aeronautics Mission. In addition to providing technology for design and development of unconventional aircraft, the techniques for generation of accurate geometry and internal sub-structure and the automated interface with the high fidelity analysis codes could also be applied towards the design of vehicles for the NASA Exploration and Space Science Mission projects.

Computing Shapes Of Cascade Diffuser Blades

NASA Technical Reports Server (NTRS)

Tran, Ken; Prueger, George H.

1993-01-01

Computer program generates sizes and shapes of cascade-type blades for use in axial or radial turbomachine diffusers. Generates shapes of blades rapidly, incorporating extensive cascade data to determine optimum incidence and deviation angle for blade design based on 65-series data base of National Advisory Commission for Aeronautics and Astronautics (NACA). Allows great variability in blade profile through input variables. Also provides for design of three-dimensional blades by allowing variable blade stacking. Enables designer to obtain computed blade-geometry data in various forms: as input for blade-loading analysis; as input for quasi-three-dimensional analysis of flow; or as points for transfer to computer-aided design.

Using Trial-Based Functional Analysis to Design Effective Interventions for Students Diagnosed with Autism Spectrum Disorder

ERIC Educational Resources Information Center

Larkin, Wallace; Hawkins, Renee O.; Collins, Tai

2016-01-01

Functional behavior assessments and function-based interventions are effective methods for addressing the challenging behaviors of children; however, traditional functional analysis has limitations that impact usability in applied settings. Trial-based functional analysis addresses concerns relating to the length of time, level of expertise…

Design and Analysis Tools for Supersonic Inlets

NASA Technical Reports Server (NTRS)

Slater, John W.; Folk, Thomas C.

2009-01-01

Computational tools are being developed for the design and analysis of supersonic inlets. The objective is to update existing tools and provide design and low-order aerodynamic analysis capability for advanced inlet concepts. The Inlet Tools effort includes aspects of creating an electronic database of inlet design information, a document describing inlet design and analysis methods, a geometry model for describing the shape of inlets, and computer tools that implement the geometry model and methods. The geometry model has a set of basic inlet shapes that include pitot, two-dimensional, axisymmetric, and stream-traced inlet shapes. The inlet model divides the inlet flow field into parts that facilitate the design and analysis methods. The inlet geometry model constructs the inlet surfaces through the generation and transformation of planar entities based on key inlet design factors. Future efforts will focus on developing the inlet geometry model, the inlet design and analysis methods, a Fortran 95 code to implement the model and methods. Other computational platforms, such as Java, will also be explored.

Probabilistic performance-based design for high performance control systems

NASA Astrophysics Data System (ADS)

Micheli, Laura; Cao, Liang; Gong, Yongqiang; Cancelli, Alessandro; Laflamme, Simon; Alipour, Alice

2017-04-01

High performance control systems (HPCS) are advanced damping systems capable of high damping performance over a wide frequency bandwidth, ideal for mitigation of multi-hazards. They include active, semi-active, and hybrid damping systems. However, HPCS are more expensive than typical passive mitigation systems, rely on power and hardware (e.g., sensors, actuators) to operate, and require maintenance. In this paper, a life cycle cost analysis (LCA) approach is proposed to estimate the economic benefit these systems over the entire life of the structure. The novelty resides in the life cycle cost analysis in the performance based design (PBD) tailored to multi-level wind hazards. This yields a probabilistic performance-based design approach for HPCS. Numerical simulations are conducted on a building located in Boston, MA. LCA are conducted for passive control systems and HPCS, and the concept of controller robustness is demonstrated. Results highlight the promise of the proposed performance-based design procedure.

Lithography hotspot discovery at 70nm DRAM 300mm fab: process window qualification using design base binning

NASA Astrophysics Data System (ADS)

Chen, Daniel; Chen, Damian; Yen, Ray; Cheng, Mingjen; Lan, Andy; Ghaskadvi, Rajesh

2008-11-01

Identifying hotspots--structures that limit the lithography process window--become increasingly important as the industry relies heavily on RET to print sub-wavelength designs. KLA-Tencor's patented Process Window Qualification (PWQ) methodology has been used for this purpose in various fabs. PWQ methodology has three key advantages (a) PWQ Layout--to obtain the best sensitivity (b) Design Based Binning--for pattern repeater analysis (c) Intelligent sampling--for the best DOI sampling rate. This paper evaluates two different analysis strategies for SEM review sampling successfully deployed at Inotera Memories, Inc. We propose a new approach combining the location repeater and pattern repeaters. Based on a recent case study the new sampling flow reduces the data analysis and sampling time from 6 hours to 1.5 hour maintaining maximum DOI sample rate.

Trellis coding with Continuous Phase Modulation (CPM) for satellite-based land-mobile communications

NASA Technical Reports Server (NTRS)

1989-01-01

This volume of the final report summarizes the results of our studies on the satellite-based mobile communications project. It includes: a detailed analysis, design, and simulations of trellis coded, full/partial response CPM signals with/without interleaving over various Rician fading channels; analysis and simulation of computational cutoff rates for coherent, noncoherent, and differential detection of CPM signals; optimization of the complete transmission system; analysis and simulation of power spectrum of the CPM signals; design and development of a class of Doppler frequency shift estimators; design and development of a symbol timing recovery circuit; and breadboard implementation of the transmission system. Studies prove the suitability of the CPM system for mobile communications.

Conversion of Component-Based Point Definition to VSP Model and Higher Order Meshing

NASA Technical Reports Server (NTRS)

Ordaz, Irian

2011-01-01

Vehicle Sketch Pad (VSP) has become a powerful conceptual and parametric geometry tool with numerous export capabilities for third-party analysis codes as well as robust surface meshing capabilities for computational fluid dynamics (CFD) analysis. However, a capability gap currently exists for reconstructing a fully parametric VSP model of a geometry generated by third-party software. A computer code called GEO2VSP has been developed to close this gap and to allow the integration of VSP into a closed-loop geometry design process with other third-party design tools. Furthermore, the automated CFD surface meshing capability of VSP are demonstrated for component-based point definition geometries in a conceptual analysis and design framework.

The NASA/industry Design Analysis Methods for Vibrations (DAMVIBS) program: A government overview

NASA Technical Reports Server (NTRS)

Kvaternik, Raymond G.

1993-01-01

NASA-Langley, under the Design Analysis Methods for Vibrations (DAMVIBS) Program, set out in 1984 to establish the technology base needed by the rotorcraft industry for developing an advanced finite-element-based dynamics design analysis capability for vibrations. Considerable work has been done by the industry participants in the program since that time. Because the DAMVIBS Program is being phased out, a government/industry assessment of the program has been made to identify those accomplishments and contributions which may be ascribed to the program. The purpose of this paper is to provide an overview of the program and its accomplishments and contributions from the perspective of the government sponsoring organization.

Probabilistic Analysis and Design of a Raked Wing Tip for a Commercial Transport

NASA Technical Reports Server (NTRS)

Mason Brian H.; Chen, Tzi-Kang; Padula, Sharon L.; Ransom, Jonathan B.; Stroud, W. Jefferson

2008-01-01

An approach for conducting reliability-based design and optimization (RBDO) of a Boeing 767 raked wing tip (RWT) is presented. The goal is to evaluate the benefits of RBDO for design of an aircraft substructure. A finite-element (FE) model that includes eight critical static load cases is used to evaluate the response of the wing tip. Thirteen design variables that describe the thickness of the composite skins and stiffeners are selected to minimize the weight of the wing tip. A strain-based margin of safety is used to evaluate the performance of the structure. The randomness in the load scale factor and in the strain limits is considered. Of the 13 variables, the wing-tip design was controlled primarily by the thickness of the thickest plies in the upper skins. The report includes an analysis of the optimization results and recommendations for future reliability-based studies.

Rdesign: A data dictionary with relational database design capabilities in Ada

NASA Technical Reports Server (NTRS)

Lekkos, Anthony A.; Kwok, Teresa Ting-Yin

1986-01-01

Data Dictionary is defined to be the set of all data attributes, which describe data objects in terms of their intrinsic attributes, such as name, type, size, format and definition. It is recognized as the data base for the Information Resource Management, to facilitate understanding and communication about the relationship between systems applications and systems data usage and to help assist in achieving data independence by permitting systems applications to access data knowledge of the location or storage characteristics of the data in the system. A research and development effort to use Ada has produced a data dictionary with data base design capabilities. This project supports data specification and analysis and offers a choice of the relational, network, and hierarchical model for logical data based design. It provides a highly integrated set of analysis and design transformation tools which range from templates for data element definition, spreadsheet for defining functional dependencies, normalization, to logical design generator.

Using Multimedia for Teaching Analysis in History of Modern Architecture.

ERIC Educational Resources Information Center

Perryman, Garry

This paper presents a case for the development and support of a computer-based interactive multimedia program for teaching analysis in community college architecture design programs. Analysis in architecture design is an extremely important strategy for the teaching of higher-order thinking skills, which senior schools of architecture look for in…

TRAC Innovative Visualization Techniques

DTIC Science & Technology

2016-11-14

Therefore, TRAC analysts need a way to analyze the effectiveness of their visualization design choices. Currently, TRAC does not have a methodology ...to analyze visualizations used to support an analysis story. Our research team developed a visualization design methodology to create effective...visualizations that support an analysis story. First, we based our methodology on the latest research on design thinking, cognitive learning, and

RADC SCAT automated sneak circuit analysis tool

NASA Astrophysics Data System (ADS)

Depalma, Edward L.

The sneak circuit analysis tool (SCAT) provides a PC-based system for real-time identification (during the design phase) of sneak paths and design concerns. The tool utilizes an expert system shell to assist the analyst so that prior experience with sneak analysis is not necessary for performance. Both sneak circuits and design concerns are targeted by this tool, with both digital and analog circuits being examined. SCAT focuses the analysis at the assembly level, rather than the entire system, so that most sneak problems can be identified and corrected by the responsible design engineer in a timely manner. The SCAT program identifies the sneak circuits to the designer, who then decides what course of action is necessary.

Numerical analysis of the performance of rock weirs: Effects of structure configuration on local hydraulics

USGS Publications Warehouse

Holmquist-Johnson, C. L.

2009-01-01

River spanning rock structures are being constructed for water delivery as well as to enable fish passage at barriers and provide or improve the aquatic habitat for endangered fish species. Current design methods are based upon anecdotal information applicable to a narrow range of channel conditions. The complex flow patterns and performance of rock weirs is not well understood. Without accurate understanding of their hydraulics, designers cannot address the failure mechanisms of these structures. Flow characteristics such as jets, near bed velocities, recirculation, eddies, and plunging flow govern scour pool development. These detailed flow patterns can be replicated using a 3D numerical model. Numerical studies inexpensively simulate a large number of cases resulting in an increased range of applicability in order to develop design tools and predictive capability for analysis and design. The analysis and results of the numerical modeling, laboratory modeling, and field data provide a process-based method for understanding how structure geometry affects flow characteristics, scour development, fish passage, water delivery, and overall structure stability. Results of the numerical modeling allow designers to utilize results of the analysis to determine the appropriate geometry for generating desirable flow parameters. The end product of this research will develop tools and guidelines for more robust structure design or retrofits based upon predictable engineering and hydraulic performance criteria. ?? 2009 ASCE.

Impacts of Climate Variability and Change on Flood Frequency Analysis for Transportation Design

DOT National Transportation Integrated Search

2010-09-01

Planning for construction of roads and bridges over rivers or floodplains includes a hydrologic analysis of rainfall amount and intensity : for a defined period. Infrastructure design must be based on accurate rainfall estimates how much (intensi...

Conformational Analysis of Drug Molecules: A Practical Exercise in the Medicinal Chemistry Course

ERIC Educational Resources Information Center

Yuriev, Elizabeth; Chalmers, David; Capuano, Ben

2009-01-01

Medicinal chemistry is a specialized, scientific discipline. Computational chemistry and structure-based drug design constitute important themes in the education of medicinal chemists. This problem-based task is associated with structure-based drug design lectures. It requires students to use computational techniques to investigate conformational…

Reliability Analysis and Reliability-Based Design Optimization of Circular Composite Cylinders Under Axial Compression

NASA Technical Reports Server (NTRS)

Rais-Rohani, Masoud

2001-01-01

This report describes the preliminary results of an investigation on component reliability analysis and reliability-based design optimization of thin-walled circular composite cylinders with average diameter and average length of 15 inches. Structural reliability is based on axial buckling strength of the cylinder. Both Monte Carlo simulation and First Order Reliability Method are considered for reliability analysis with the latter incorporated into the reliability-based structural optimization problem. To improve the efficiency of reliability sensitivity analysis and design optimization solution, the buckling strength of the cylinder is estimated using a second-order response surface model. The sensitivity of the reliability index with respect to the mean and standard deviation of each random variable is calculated and compared. The reliability index is found to be extremely sensitive to the applied load and elastic modulus of the material in the fiber direction. The cylinder diameter was found to have the third highest impact on the reliability index. Also the uncertainty in the applied load, captured by examining different values for its coefficient of variation, is found to have a large influence on cylinder reliability. The optimization problem for minimum weight is solved subject to a design constraint on element reliability index. The methodology, solution procedure and optimization results are included in this report.

Design and analysis of sustainable paper bicycle

NASA Astrophysics Data System (ADS)

Roni Sahroni, Taufik; Nasution, Januar

2017-12-01

This paper presents the design of sustainable paper bicycle which describes the stage by stage in the production of paper bicycle. The objective of this project is to design a sustainable paper bicycles to be used for children under five years old. The design analysis emphasizes in screening method to ensure the design fulfil the safety purposes. The evaluation concept is presented in designing a sustainable paper bicycle to determine highest rating. Project methodology is proposed for developing a sustainable paper bicycle. Design analysis of pedal, front and rear wheel, seat, and handle were presented using AutoCAD software. The design optimization was performed to fulfil the safety factors by modifying the material size and dimension. Based on the design analysis results, it is found that the optimization results met the factor safety. As a result, a sustainable paper bicycle was proposed for children under five years old.

Regression Model for Light Weight and Crashworthiness Enhancement Design of Automotive Parts in Frontal CAR Crash

NASA Astrophysics Data System (ADS)

Bae, Gihyun; Huh, Hoon; Park, Sungho

This paper deals with a regression model for light weight and crashworthiness enhancement design of automotive parts in frontal car crash. The ULSAB-AVC model is employed for the crash analysis and effective parts are selected based on the amount of energy absorption during the crash behavior. Finite element analyses are carried out for designated design cases in order to investigate the crashworthiness and weight according to the material and thickness of main energy absorption parts. Based on simulations results, a regression analysis is performed to construct a regression model utilized for light weight and crashworthiness enhancement design of automotive parts. An example for weight reduction of main energy absorption parts demonstrates the validity of a regression model constructed.

Structural Design of Ares V Interstage Composite Structure

NASA Technical Reports Server (NTRS)

Sleigh, David W.; Sreekantamurthy, Thammaiah; Kosareo, Daniel N.; Martin, Robert A.; Johnson, Theodore F.

2011-01-01

Preliminary and detailed design studies were performed to mature composite structural design concepts for the Ares V Interstage structure as a part of NASA s Advanced Composite Technologies Project. Aluminum honeycomb sandwich and hat-stiffened composite panel structural concepts were considered. The structural design and analysis studies were performed using HyperSizer design sizing software and MSC Nastran finite element analysis software. System-level design trade studies were carried out to predict weight and margins of safety for composite honeycomb-core sandwich and composite hat-stiffened skin design concepts. Details of both preliminary and detailed design studies are presented in the paper. For the range of loads and geometry considered in this work, the hat-stiffened designs were found to be approximately 11-16 percent lighter than the sandwich designs. A down-select process was used to choose the most favorable structural concept based on a set of figures of merit, and the honeycomb sandwich design was selected as the best concept based on advantages in manufacturing cost.

Using Android-Based Educational Game for Learning Colloid Material

NASA Astrophysics Data System (ADS)

Sari, S.; Anjani, R.; Farida, I.; Ramdhani, M. A.

2017-09-01

This research is based on the importance of the development of student’s chemical literacy on Colloid material using Android-based educational game media. Educational game products are developed through research and development design. In the analysis phase, material analysis is performed to generate concept maps, determine chemical literacy indicators, game strategies and set game paths. In the design phase, product packaging is carried out, then validation and feasibility test are performed. Research produces educational game based on Android that has the characteristics that is: Colloid material presented in 12 levels of game in the form of questions and challenges, presents visualization of discourse, images and animation contextually to develop the process of thinking and attitude. Based on the analysis of validation and trial results, the product is considered feasible to use.

A 3D Human-Machine Integrated Design and Analysis Framework for Squat Exercises with a Smith Machine.

PubMed

Lee, Haerin; Jung, Moonki; Lee, Ki-Kwang; Lee, Sang Hun

2017-02-06

In this paper, we propose a three-dimensional design and evaluation framework and process based on a probabilistic-based motion synthesis algorithm and biomechanical analysis system for the design of the Smith machine and squat training programs. Moreover, we implemented a prototype system to validate the proposed framework. The framework consists of an integrated human-machine-environment model as well as a squat motion synthesis system and biomechanical analysis system. In the design and evaluation process, we created an integrated model in which interactions between a human body and machine or the ground are modeled as joints with constraints at contact points. Next, we generated Smith squat motion using the motion synthesis program based on a Gaussian process regression algorithm with a set of given values for independent variables. Then, using the biomechanical analysis system, we simulated joint moments and muscle activities from the input of the integrated model and squat motion. We validated the model and algorithm through physical experiments measuring the electromyography (EMG) signals, ground forces, and squat motions as well as through a biomechanical simulation of muscle forces. The proposed approach enables the incorporation of biomechanics in the design process and reduces the need for physical experiments and prototypes in the development of training programs and new Smith machines.

A 3D Human-Machine Integrated Design and Analysis Framework for Squat Exercises with a Smith Machine

PubMed Central

Lee, Haerin; Jung, Moonki; Lee, Ki-Kwang; Lee, Sang Hun

2017-01-01

In this paper, we propose a three-dimensional design and evaluation framework and process based on a probabilistic-based motion synthesis algorithm and biomechanical analysis system for the design of the Smith machine and squat training programs. Moreover, we implemented a prototype system to validate the proposed framework. The framework consists of an integrated human–machine–environment model as well as a squat motion synthesis system and biomechanical analysis system. In the design and evaluation process, we created an integrated model in which interactions between a human body and machine or the ground are modeled as joints with constraints at contact points. Next, we generated Smith squat motion using the motion synthesis program based on a Gaussian process regression algorithm with a set of given values for independent variables. Then, using the biomechanical analysis system, we simulated joint moments and muscle activities from the input of the integrated model and squat motion. We validated the model and algorithm through physical experiments measuring the electromyography (EMG) signals, ground forces, and squat motions as well as through a biomechanical simulation of muscle forces. The proposed approach enables the incorporation of biomechanics in the design process and reduces the need for physical experiments and prototypes in the development of training programs and new Smith machines. PMID:28178184

Using SEM to Analyze Complex Survey Data: A Comparison between Design-Based Single-Level and Model-Based Multilevel Approaches

ERIC Educational Resources Information Center

Wu, Jiun-Yu; Kwok, Oi-man

2012-01-01

Both ad-hoc robust sandwich standard error estimators (design-based approach) and multilevel analysis (model-based approach) are commonly used for analyzing complex survey data with nonindependent observations. Although these 2 approaches perform equally well on analyzing complex survey data with equal between- and within-level model structures…

[Continual improvement of quantitative analytical method development of Panax notogineng saponins based on quality by design].

PubMed

Dai, Sheng-Yun; Xu, Bing; Shi, Xin-Yuan; Xu, Xiang; Sun, Ying-Qiang; Qiao, Yan-Jiang

2017-03-01

This study is aimed to propose a continual improvement strategy based on quality by design (QbD). An ultra high performance liquid chromatography (UPLC) method was developed to accomplish the method transformation from HPLC to UPLC of Panax notogineng saponins (PNS) and achieve the continual improvement of PNS based on QbD, for example. Plackett-Burman screening design and Box-Behnken optimization design were employed to further understand the relationship between the critical method parameters (CMPs) and critical method attributes (CMAs). And then the Bayesian design space was built. The separation degree of the critical peaks (ginsenoside Rg₁ and ginsenoside Re) was over 2.0 and the analysis time was less than 17 min by a method chosen from the design space with 20% of the initial concentration of the acetonitrile, 10 min of the isocratic time and 6%•min⁻¹ of the gradient slope. At last, the optimum method was validated by accuracy profile. Based on the same analytical target profile (ATP), the comparison of HPLC and UPLC including chromatograph method, CMA identification, CMP-CMA model and system suitability test (SST) indicated that the UPLC method could shorten the analysis time, improve the critical separation and satisfy the requirement of the SST. In all, HPLC method could be replaced by UPLC for the quantity analysis of PNS. Copyright© by the Chinese Pharmaceutical Association.

Advanced microgrid design and analysis for forward operating bases

NASA Astrophysics Data System (ADS)

Reasoner, Jonathan

This thesis takes a holistic approach in creating an improved electric power generation system for a forward operating base (FOB) in the future through the design of an isolated microgrid. After an extensive literature search, this thesis found a need for drastic improvement of the FOB power system. A thorough design process analyzed FOB demand, researched demand side management improvements, evaluated various generation sources and energy storage options, and performed a HOMERRTM discrete optimization to determine the best microgrid design. Further sensitivity analysis was performed to see how changing parameters would affect the outcome. Lastly, this research also looks at some of the challenges which are associated with incorporating a design which relies heavily on inverter-based generation sources, and gives possible solutions to help make a renewable energy powered microgrid a reality. While this thesis uses a FOB as the case study, the process and discussion can be adapted to aide in the design of an off-grid small-scale power grid which utilizes high-penetration levels of renewable energy.

Making the most of sparse clinical data by using a predictive-model-based analysis, illustrated with a stavudine pharmacokinetic study.

PubMed

Zhang, L; Price, R; Aweeka, F; Bellibas, S E; Sheiner, L B

2001-02-01

A small-scale clinical investigation was done to quantify the penetration of stavudine (D4T) into cerebrospinal fluid (CSF). A model-based analysis estimates the steady-state ratio of AUCs of CSF and plasma concentrations (R(AUC)) to be 0.270, and the mean residence time of drug in the CSF to be 7.04 h. The analysis illustrates the advantages of a causal (scientific, predictive) model-based approach to analysis over a noncausal (empirical, descriptive) approach when the data, as here, demonstrate certain problematic features commonly encountered in clinical data, namely (i) few subjects, (ii) sparse sampling, (iii) repeated measures, (iv) imbalance, and (v) individual design variation. These features generally require special attention in data analysis. The causal-model-based analysis deals with features (i) and (ii), both of which reduce efficiency, by combining data from different studies and adding subject-matter prior information. It deals with features (iii)--(v), all of which prevent 'averaging' individual data points directly, first, by adjusting in the model for interindividual data differences due to design differences, secondly, by explicitly differentiating between interpatient, interoccasion, and measurement error variation, and lastly, by defining a scientifically meaningful estimand (R(AUC)) that is independent of design.

Computer-Aided Design Applications for the Base Civil Engineering Technical Design Section.

DTIC Science & Technology

1983-09-01

4 1983.’ S DEPARTMENT OF TiHE AIR FORCE L ~j AIR UNIVERSITY * AIR FORCE INSTITUTE OF TECHNOLOGY Nam Wright- Patterson Air Force Bas, Ohio d ’rI ’ 4to...I -. L I 1it it COMPUTER-AIDED DESIGN APPLICATIONS FOR THE BASE CIVIL ENGINEERING TECHNICAL DESIGN SECTION William M. Duncan, Captain, USAF LSSR 15-83...8217 .. ’ , .. - -. . ’ . , ._, - . . - .2 , _ : ’i 1 . . . . .- J.. .. . ’ _ -i l - , . analysis and design, water supply and wastewater disposal system design, and most

The NASA/Industry Design Analysis Methods for Vibrations (DAMVIBS) Program - A government overview. [of rotorcraft technology development using finite element method

NASA Technical Reports Server (NTRS)

Kvaternik, Raymond G.

1992-01-01

An overview is presented of government contributions to the program called Design Analysis Methods for Vibrations (DAMV) which attempted to develop finite-element-based analyses of rotorcraft vibrations. NASA initiated the program with a finite-element modeling program for the CH-47D tandem-rotor helicopter. The DAMV program emphasized four areas including: airframe finite-element modeling, difficult components studies, coupled rotor-airframe vibrations, and airframe structural optimization. Key accomplishments of the program include industrywide standards for modeling metal and composite airframes, improved industrial designs for vibrations, and the identification of critical structural contributors to airframe vibratory responses. The program also demonstrated the value of incorporating secondary modeling details to improving correlation, and the findings provide the basis for an improved finite-element-based dynamics design-analysis capability.

Towards Improved Considerations of Risk in Seismic Design (Plinius Medal Lecture)

NASA Astrophysics Data System (ADS)

Sullivan, T. J.

2012-04-01

The aftermath of recent earthquakes is a reminder that seismic risk is a very relevant issue for our communities. Implicit within the seismic design standards currently in place around the world is that minimum acceptable levels of seismic risk will be ensured through design in accordance with the codes. All the same, none of the design standards specify what the minimum acceptable level of seismic risk actually is. Instead, a series of deterministic limit states are set which engineers then demonstrate are satisfied for their structure, typically through the use of elastic dynamic analyses adjusted to account for non-linear response using a set of empirical correction factors. From the early nineties the seismic engineering community has begun to recognise numerous fundamental shortcomings with such seismic design procedures in modern codes. Deficiencies include the use of elastic dynamic analysis for the prediction of inelastic force distributions, the assignment of uniform behaviour factors for structural typologies irrespective of the structural proportions and expected deformation demands, and the assumption that hysteretic properties of a structure do not affect the seismic displacement demands, amongst other things. In light of this a number of possibilities have emerged for improved control of risk through seismic design, with several innovative displacement-based seismic design methods now well developed. For a specific seismic design intensity, such methods provide a more rational means of controlling the response of a structure to satisfy performance limit states. While the development of such methodologies does mark a significant step forward for the control of seismic risk, they do not, on their own, identify the seismic risk of a newly designed structure. In the U.S. a rather elaborate performance-based earthquake engineering (PBEE) framework is under development, with the aim of providing seismic loss estimates for new buildings. The PBEE framework consists of the following four main analysis stages: (i) probabilistic seismic hazard analysis to give the mean occurrence rate of earthquake events having an intensity greater than a threshold value, (ii) structural analysis to estimate the global structural response, given a certain value of seismic intensity, (iii) damage analysis, in which fragility functions are used to express the probability that a building component exceeds a damage state, as a function of the global structural response, (iv) loss analysis, in which the overall performance is assessed based on the damage state of all components. This final step gives estimates of the mean annual frequency with which various repair cost levels (or other decision variables) are exceeded. The realisation of this framework does suggest that risk-based seismic design is now possible. However, comparing current code approaches with the proposed PBEE framework, it becomes apparent that mainstream consulting engineers would have to go through a massive learning curve in order to apply the new procedures in practice. With this in mind, it is proposed that simplified loss-based seismic design procedures are a logical means of helping the engineering profession transition from what are largely deterministic seismic design procedures in current codes, to more rational risk-based seismic design methodologies. Examples are provided to illustrate the likely benefits of adopting loss-based seismic design approaches in practice.

Wind study for high altitude platform design

NASA Technical Reports Server (NTRS)

Strganac, T. W.

1979-01-01

An analysis of upper air winds was performed to define the wind environment at potential operating altitudes for high-altitude powered platform concepts. Expected wind conditions of the contiguous United States, Pacific area (Alaska to Sea of Japan), and European area (Norwegian and Mediterranean Seas) were obtained using a representative network of sites selected based upon adequate high-altitude sampling, geographic dispersion, and observed upper wind patterns. A data base of twenty plus years of rawinsonde gathered wind information was used in the analysis. Annual variations from surface to 10 mb (approximately 31 km) pressure altitude were investigated to encompass the practical operating range for the platform concepts. Parametric analysis for the United States and foreign areas was performed to provide a basis for vehicle system design tradeoffs. This analysis of wind magnitudes indicates the feasibility of annual operation at a majority of sites and more selective seasonal operation for the extreme conditions between the pressure altitudes of 100 to 25 mb based upon the assumed design speeds.

Wind study for high altitude platform design

NASA Technical Reports Server (NTRS)

Strganac, T. W.

1979-01-01

An analysis of upper air winds was performed to define the wind environment at potential operating altitudes for high altitude powered platform concepts. Wind conditions of the continental United States, Pacific area (Alaska to Sea of Japan), and European area (Norwegian and Mediterranean Sea) were obtained using a representative network of sites selected based upon adequate high altitude sampling, geographic dispersion, and observed upper wind patterns. A data base of twenty plus years of rawinsonde gathered wind information was used in the analysis. Annual variations from surface to 10 mb pressure altitude were investigated to encompass the practical operating range for the platform concepts. Parametric analysis for the United States and foreign areas was performed to provide a basis for vehicle system design tradeoffs. This analysis of wind magnitudes indicates the feasibility of annual operation at a majority of sites and more selective seasonal operation for the extreme conditions between the pressure altitudes of 100 to 25 mb based upon the assumed design speeds.

Systematic analysis of signaling pathways using an integrative environment.

PubMed

Visvanathan, Mahesh; Breit, Marc; Pfeifer, Bernhard; Baumgartner, Christian; Modre-Osprian, Robert; Tilg, Bernhard

2007-01-01

Understanding the biological processes of signaling pathways as a whole system requires an integrative software environment that has comprehensive capabilities. The environment should include tools for pathway design, visualization, simulation and a knowledge base concerning signaling pathways as one. In this paper we introduce a new integrative environment for the systematic analysis of signaling pathways. This system includes environments for pathway design, visualization, simulation and a knowledge base that combines biological and modeling information concerning signaling pathways that provides the basic understanding of the biological system, its structure and functioning. The system is designed with a client-server architecture. It contains a pathway designing environment and a simulation environment as upper layers with a relational knowledge base as the underlying layer. The TNFa-mediated NF-kB signal trans-duction pathway model was designed and tested using our integrative framework. It was also useful to define the structure of the knowledge base. Sensitivity analysis of this specific pathway was performed providing simulation data. Then the model was extended showing promising initial results. The proposed system offers a holistic view of pathways containing biological and modeling data. It will help us to perform biological interpretation of the simulation results and thus contribute to a better understanding of the biological system for drug identification.

The Efficiency of Split Panel Designs in an Analysis of Variance Model

PubMed Central

Wang, Wei-Guo; Liu, Hai-Jun

2016-01-01

We consider split panel design efficiency in analysis of variance models, that is, the determination of the cross-sections series optimal proportion in all samples, to minimize parametric best linear unbiased estimators of linear combination variances. An orthogonal matrix is constructed to obtain manageable expression of variances. On this basis, we derive a theorem for analyzing split panel design efficiency irrespective of interest and budget parameters. Additionally, relative estimator efficiency based on the split panel to an estimator based on a pure panel or a pure cross-section is present. The analysis shows that the gains from split panel can be quite substantial. We further consider the efficiency of split panel design, given a budget, and transform it to a constrained nonlinear integer programming. Specifically, an efficient algorithm is designed to solve the constrained nonlinear integer programming. Moreover, we combine one at time designs and factorial designs to illustrate the algorithm’s efficiency with an empirical example concerning monthly consumer expenditure on food in 1985, in the Netherlands, and the efficient ranges of the algorithm parameters are given to ensure a good solution. PMID:27163447

Design of an image encryption scheme based on a multiple chaotic map

NASA Astrophysics Data System (ADS)

Tong, Xiao-Jun

2013-07-01

In order to solve the problem that chaos is degenerated in limited computer precision and Cat map is the small key space, this paper presents a chaotic map based on topological conjugacy and the chaotic characteristics are proved by Devaney definition. In order to produce a large key space, a Cat map named block Cat map is also designed for permutation process based on multiple-dimensional chaotic maps. The image encryption algorithm is based on permutation-substitution, and each key is controlled by different chaotic maps. The entropy analysis, differential analysis, weak-keys analysis, statistical analysis, cipher random analysis, and cipher sensibility analysis depending on key and plaintext are introduced to test the security of the new image encryption scheme. Through the comparison to the proposed scheme with AES, DES and Logistic encryption methods, we come to the conclusion that the image encryption method solves the problem of low precision of one dimensional chaotic function and has higher speed and higher security.

Airport Pavement Design For The Boeing 777 Airplane

DOT National Transportation Integrated Search

1995-10-22

The purpose of this advisory circular is to provide thickness design standards : for pavements intended to serve the Boeing 777 airplane. A new method of design : based on layered elastic analysis has been developed to calculate design : thickness fo...

Direct coal liquefaction baseline design and system analysis. Quarterly report, January--March 1991

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

Not Available

1991-04-01

The primary objective of the study is to develop a computer model for a base line direct coal liquefaction design based on two stage direct coupled catalytic reactors. This primary objective is to be accomplished by completing the following: a base line design based on previous DOE/PETC results from Wilsonville pilot plant and other engineering evaluations; a cost estimate and economic analysis; a computer model incorporating the above two steps over a wide range of capacities and selected process alternatives; a comprehensive training program for DOE/PETC Staff to understand and use the computer model; a thorough documentation of all underlyingmore » assumptions for baseline economics; and a user manual and training material which will facilitate updating of the model in the future.« less

Direct coal liquefaction baseline design and system analysis

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

Not Available

1991-04-01

The primary objective of the study is to develop a computer model for a base line direct coal liquefaction design based on two stage direct coupled catalytic reactors. This primary objective is to be accomplished by completing the following: a base line design based on previous DOE/PETC results from Wilsonville pilot plant and other engineering evaluations; a cost estimate and economic analysis; a computer model incorporating the above two steps over a wide range of capacities and selected process alternatives; a comprehensive training program for DOE/PETC Staff to understand and use the computer model; a thorough documentation of all underlyingmore » assumptions for baseline economics; and a user manual and training material which will facilitate updating of the model in the future.« less

Failure modes and effects analysis automation

NASA Technical Reports Server (NTRS)

Kamhieh, Cynthia H.; Cutts, Dannie E.; Purves, R. Byron

1988-01-01

A failure modes and effects analysis (FMEA) assistant was implemented as a knowledge based system and will be used during design of the Space Station to aid engineers in performing the complex task of tracking failures throughout the entire design effort. The three major directions in which automation was pursued were the clerical components of the FMEA process, the knowledge acquisition aspects of FMEA, and the failure propagation/analysis portions of the FMEA task. The system is accessible to design, safety, and reliability engineers at single user workstations and, although not designed to replace conventional FMEA, it is expected to decrease by many man years the time required to perform the analysis.

Principles of Design for High Performing Organizations: An Assessment of the State of the Field of Organizational Design Research

DTIC Science & Technology

1994-03-01

asked whether the planned structure considered (a) all objectives, (b) all functions, (c) all relevant units of analysis such as the plant , the...literature and provides an integrative model of design for high perfor-ming organizations. The model is based on an analysis of current theories of...important midrange theories underlie much of the work on organizational analysis . 0 Systems Approaches. These approaches emphasize the rational, goal

User-Centered Design Guidelines for Collaborative Software for Intelligence Analysis

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

Scholtz, Jean; Endert, Alexander N.

In this position paper we discuss the necessity of using User-Centered Design (UCD) methods in order to design collaborative software for the intelligence community. We present some standing issues in collaborative software based on existing work within the intelligence community. Based on this information we present opportunities to address some of these challenges.

Web-Based Tools for Designing and Developing Teaching Materials for Integration of Information Technology into Instruction

ERIC Educational Resources Information Center

Chang, Kuo-En; Sung, Yao-Ting; Hou, Huei-Tse

2006-01-01

Educational software for teachers is an important, yet usually ignored, link for integrating information technology into classroom instruction. This study builds a web-based teaching material design and development system. The process in the system is divided into four stages, analysis, design, development, and practice. Eight junior high school…

Investigation of Weibull statistics in fracture analysis of cast aluminum

NASA Technical Reports Server (NTRS)

Holland, Frederic A., Jr.; Zaretsky, Erwin V.

1989-01-01

The fracture strengths of two large batches of A357-T6 cast aluminum coupon specimens were compared by using two-parameter Weibull analysis. The minimum number of these specimens necessary to find the fracture strength of the material was determined. The applicability of three-parameter Weibull analysis was also investigated. A design methodology based on the combination of elementary stress analysis and Weibull statistical analysis is advanced and applied to the design of a spherical pressure vessel shell. The results from this design methodology are compared with results from the applicable ASME pressure vessel code.

CFD Analysis of Turbo Expander for Cryogenic Refrigeration and Liquefaction Cycles

NASA Astrophysics Data System (ADS)

Verma, Rahul; Sam, Ashish Alex; Ghosh, Parthasarathi

Computational Fluid Dynamics analysis has emerged as a necessary tool for designing of turbomachinery. It helps to understand the various sources of inefficiency through investigation of flow physics of the turbine. In this paper, 3D turbulent flow analysis of a cryogenic turboexpander for small scale air separation was performed using Ansys CFX®. The turboexpander has been designed following assumptions based on meanlineblade generation procedure provided in open literature and good engineering judgement. Through analysis of flow field, modifications and further analysis required to evolve a more robust design procedure, have been suggested.

Category's analysis and operational project capacity method of transformation in design

NASA Astrophysics Data System (ADS)

Obednina, S. V.; Bystrova, T. Y.

2015-10-01

The method of transformation is attracting widespread interest in fields such contemporary design. However, in theory of design little attention has been paid to a categorical status of the term "transformation". This paper presents the conceptual analysis of transformation based on the theory of form employed in the influential essays by Aristotle and Thomas Aquinas. In the present work the transformation as a method of shaping design has been explored as well as potential application of this term in design has been demonstrated.

A probabilistic approach to aircraft design emphasizing stability and control uncertainties

NASA Astrophysics Data System (ADS)

Delaurentis, Daniel Andrew

In order to address identified deficiencies in current approaches to aerospace systems design, a new method has been developed. This new method for design is based on the premise that design is a decision making activity, and that deterministic analysis and synthesis can lead to poor, or misguided decision making. This is due to a lack of disciplinary knowledge of sufficient fidelity about the product, to the presence of uncertainty at multiple levels of the aircraft design hierarchy, and to a failure to focus on overall affordability metrics as measures of goodness. Design solutions are desired which are robust to uncertainty and are based on the maximum knowledge possible. The new method represents advances in the two following general areas. 1. Design models and uncertainty. The research performed completes a transition from a deterministic design representation to a probabilistic one through a modeling of design uncertainty at multiple levels of the aircraft design hierarchy, including: (1) Consistent, traceable uncertainty classification and representation; (2) Concise mathematical statement of the Probabilistic Robust Design problem; (3) Variants of the Cumulative Distribution Functions (CDFs) as decision functions for Robust Design; (4) Probabilistic Sensitivities which identify the most influential sources of variability. 2. Multidisciplinary analysis and design. Imbedded in the probabilistic methodology is a new approach for multidisciplinary design analysis and optimization (MDA/O), employing disciplinary analysis approximations formed through statistical experimentation and regression. These approximation models are a function of design variables common to the system level as well as other disciplines. For aircraft, it is proposed that synthesis/sizing is the proper avenue for integrating multiple disciplines. Research hypotheses are translated into a structured method, which is subsequently tested for validity. Specifically, the implementation involves the study of the relaxed static stability technology for a supersonic commercial transport aircraft. The probabilistic robust design method is exercised resulting in a series of robust design solutions based on different interpretations of "robustness". Insightful results are obtained and the ability of the method to expose trends in the design space are noted as a key advantage.

Applications of Response Surface-Based Methods to Noise Analysis in the Conceptual Design of Revolutionary Aircraft

NASA Technical Reports Server (NTRS)

Hill, Geoffrey A.; Olson, Erik D.

2004-01-01

Due to the growing problem of noise in today's air transportation system, there have arisen needs to incorporate noise considerations in the conceptual design of revolutionary aircraft. Through the use of response surfaces, complex noise models may be converted into polynomial equations for rapid and simplified evaluation. This conversion allows many of the commonly used response surface-based trade space exploration methods to be applied to noise analysis. This methodology is demonstrated using a noise model of a notional 300 passenger Blended-Wing-Body (BWB) transport. Response surfaces are created relating source noise levels of the BWB vehicle to its corresponding FAR-36 certification noise levels and the resulting trade space is explored. Methods demonstrated include: single point analysis, parametric study, an optimization technique for inverse analysis, sensitivity studies, and probabilistic analysis. Extended applications of response surface-based methods in noise analysis are also discussed.

Curriculum and Design Analysis of a Mathematics-Based Educational Television Program: A Case Study of Cyberchase Animated Television Series

ERIC Educational Resources Information Center

Yusop, Farrah Dina

2013-01-01

This paper presents a curriculum and design analyses of an Emmy-award winning children educational television series, Cyberchase. Using Posner's (2004) four process of curriculum analysis framework, this paper addresses each of the components and relates it to the design principles undertaken by the Cyberchase production team. Media and document…

The Effect of a Computer Program Based on Analysis, Design, Development, Implementation and Evaluation (ADDIE) in Improving Ninth Graders' Listening and Reading Comprehension Skills in English in Jordan

ERIC Educational Resources Information Center

Alodwan, Talal; Almosa, Mosaab

2018-01-01

The study aimed to assess the effectiveness of a computer program based on Analysis, Design, Development, Implementation and Evaluation (ADDIE) Model on the achievement of Ninth Graders' listening and Reading Comprehension Skills in English. The study sample comprised 70 ninth graders during the second semester of the academic year 2016/2017. The…

Manned space flight nuclear system safety. Volume 3: Reactor system preliminary nuclear safety analysis. Part 1: Reference Design Document (RDD)

NASA Technical Reports Server (NTRS)

1972-01-01

The Reference Design Document, of the Preliminary Safety Analysis Report (PSAR) - Reactor System provides the basic design and operations data used in the nuclear safety analysis of the Rector Power Module as applied to a Space Base program. A description of the power module systems, facilities, launch vehicle and mission operations, as defined in NASA Phase A Space Base studies is included. Each of two Zirconium Hydride Reactor Brayton power modules provides 50 kWe for the nominal 50 man Space Base. The INT-21 is the prime launch vehicle. Resupply to the 500 km orbit over the ten year mission is provided by the Space Shuttle. At the end of the power module lifetime (nominally five years), a reactor disposal system is deployed for boost into a 990 km high altitude (long decay time) earth orbit.

Fusing Quantitative Requirements Analysis with Model-based Systems Engineering

NASA Technical Reports Server (NTRS)

Cornford, Steven L.; Feather, Martin S.; Heron, Vance A.; Jenkins, J. Steven

2006-01-01

A vision is presented for fusing quantitative requirements analysis with model-based systems engineering. This vision draws upon and combines emergent themes in the engineering milieu. "Requirements engineering" provides means to explicitly represent requirements (both functional and non-functional) as constraints and preferences on acceptable solutions, and emphasizes early-lifecycle review, analysis and verification of design and development plans. "Design by shopping" emphasizes revealing the space of options available from which to choose (without presuming that all selection criteria have previously been elicited), and provides means to make understandable the range of choices and their ramifications. "Model-based engineering" emphasizes the goal of utilizing a formal representation of all aspects of system design, from development through operations, and provides powerful tool suites that support the practical application of these principles. A first step prototype towards this vision is described, embodying the key capabilities. Illustrations, implications, further challenges and opportunities are outlined.

Analysis of DNA Sequences by an Optical Time-Integrating Correlator: Proof-of-Concept Experiments.

DTIC Science & Technology

1992-05-01

DNA ANALYSIS STRATEGY 4 2.1 Representation of DNA Bases 4 2.2 DNA Analysis Strategy 6 3.0 CUSTOM GENERATORS FOR DNA SEQUENCES 10 3.1 Hardware Design 10...of the DNA bases where each base is represented by a 7-bits long pseudorandom sequence. 5 Figure 4: Coarse analysis of a DNA sequence. 7 Figure 5: Fine...a 20-bases long database. 32 xiii LIST OF TABLES PAGE Table 1: Short representations of the DNA bases where each base is represented by 7-bits long

Design of Energy Storage Reactors for Dc-To-Dc Converters. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Chen, D. Y.

1975-01-01

Two methodical approaches to the design of energy-storage reactors for a group of widely used dc-to-dc converters are presented. One of these approaches is based on a steady-state time-domain analysis of piecewise-linearized circuit models of the converters, while the other approach is based on an analysis of the same circuit models, but from an energy point of view. The design procedure developed from the first approach includes a search through a stored data file of magnetic core characteristics and results in a list of usable reactor designs which meet a particular converter's requirements. Because of the complexity of this procedure, a digital computer usually is used to implement the design algorithm. The second approach, based on a study of the storage and transfer of energy in the magnetic reactors, leads to a straightforward design procedure which can be implemented with hand calculations. An equation to determine the lower-bound volume of workable cores for given converter design specifications is derived. Using this computer lower-bound volume, a comparative evaluation of various converter configurations is presented.

Design and construction of an Offner spectrometer based on geometrical analysis of ring fields.

PubMed

Kim, Seo Hyun; Kong, Hong Jin; Lee, Jong Ung; Lee, Jun Ho; Lee, Jai Hoon

2014-08-01

A method to obtain an aberration-corrected Offner spectrometer without ray obstruction is proposed. A new, more efficient spectrometer optics design is suggested in order to increase its spectral resolution. The derivation of a new ring equation to eliminate ray obstruction is based on geometrical analysis of the ring fields for various numerical apertures. The analytical design applying this equation was demonstrated using the optical design software Code V in order to manufacture a spectrometer working in wavelengths of 900-1700 nm. The simulation results show that the new concept offers an analytical initial design taking the least time of calculation. The simulated spectrometer exhibited a modulation transfer function over 80% at Nyquist frequency, root-mean-square spot diameters under 8.6 μm, and a spectral resolution of 3.2 nm. The final design and its realization of a high resolution Offner spectrometer was demonstrated based on the simulation result. The equation and analytical design procedure shown here can be applied to most Offner systems regardless of the wavelength range.

Integration of Molecular Dynamics Based Predictions into the Optimization of De Novo Protein Designs: Limitations and Benefits.

PubMed

Carvalho, Henrique F; Barbosa, Arménio J M; Roque, Ana C A; Iranzo, Olga; Branco, Ricardo J F

2017-01-01

Recent advances in de novo protein design have gained considerable insight from the intrinsic dynamics of proteins, based on the integration of molecular dynamics simulations protocols on the state-of-the-art de novo protein design protocols used nowadays. With this protocol we illustrate how to set up and run a molecular dynamics simulation followed by a functional protein dynamics analysis. New users will be introduced to some useful open-source computational tools, including the GROMACS molecular dynamics simulation software package and ProDy for protein structural dynamics analysis.

Analysis of Levene's Test under Design Imbalance.

ERIC Educational Resources Information Center

Keyes, Tim K.; Levy, Martin S.

1997-01-01

H. Levene (1960) proposed a heuristic test for heteroscedasticity in the case of a balanced two-way layout, based on analysis of variance of absolute residuals. Conditions under which design imbalance affects the test's characteristics are identified, and a simple correction involving leverage is proposed. (SLD)

Full 3D visualization tool-kit for Monte Carlo and deterministic transport codes

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

Frambati, S.; Frignani, M.

2012-07-01

We propose a package of tools capable of translating the geometric inputs and outputs of many Monte Carlo and deterministic radiation transport codes into open source file formats. These tools are aimed at bridging the gap between trusted, widely-used radiation analysis codes and very powerful, more recent and commonly used visualization software, thus supporting the design process and helping with shielding optimization. Three main lines of development were followed: mesh-based analysis of Monte Carlo codes, mesh-based analysis of deterministic codes and Monte Carlo surface meshing. The developed kit is considered a powerful and cost-effective tool in the computer-aided design formore » radiation transport code users of the nuclear world, and in particular in the fields of core design and radiation analysis. (authors)« less

Planning for a data base system to support satellite conceptual design

NASA Technical Reports Server (NTRS)

Claydon, C. R.

1976-01-01

The conceptual design of an automated satellite design data base system is presented. The satellite catalog in the system includes data for all earth orbital satellites funded to the hardware stage for launch between 1970 and 1980, and provides a concise compilation of satellite capabilities and design parameters. The cost of satellite subsystems and components will be added to the base. Data elements are listed and discussed. Sensor and science and applications opportunities catalogs will be included in the data system. Capabilities of the BASIS storage, retrieval, and analysis system are used in the system design.

Nuclear Engine System Simulation (NESS). Volume 1: Program user's guide

NASA Astrophysics Data System (ADS)

Pelaccio, Dennis G.; Scheil, Christine M.; Petrosky, Lyman J.

1993-03-01

A Nuclear Thermal Propulsion (NTP) engine system design analysis tool is required to support current and future Space Exploration Initiative (SEI) propulsion and vehicle design studies. Currently available NTP engine design models are those developed during the NERVA program in the 1960's and early 1970's and are highly unique to that design or are modifications of current liquid propulsion system design models. To date, NTP engine-based liquid design models lack integrated design of key NTP engine design features in the areas of reactor, shielding, multi-propellant capability, and multi-redundant pump feed fuel systems. Additionally, since the SEI effort is in the initial development stage, a robust, verified NTP analysis design tool could be of great use to the community. This effort developed an NTP engine system design analysis program (tool), known as the Nuclear Engine System Simulation (NESS) program, to support ongoing and future engine system and stage design study efforts. In this effort, Science Applications International Corporation's (SAIC) NTP version of the Expanded Liquid Engine Simulation (ELES) program was modified extensively to include Westinghouse Electric Corporation's near-term solid-core reactor design model. The ELES program has extensive capability to conduct preliminary system design analysis of liquid rocket systems and vehicles. The program is modular in nature and is versatile in terms of modeling state-of-the-art component and system options as discussed. The Westinghouse reactor design model, which was integrated in the NESS program, is based on the near-term solid-core ENABLER NTP reactor design concept. This program is now capable of accurately modeling (characterizing) a complete near-term solid-core NTP engine system in great detail, for a number of design options, in an efficient manner. The following discussion summarizes the overall analysis methodology, key assumptions, and capabilities associated with the NESS presents an example problem, and compares the results to related NTP engine system designs. Initial installation instructions and program disks are in Volume 2 of the NESS Program User's Guide.

Nuclear Engine System Simulation (NESS). Volume 1: Program user's guide

NASA Technical Reports Server (NTRS)

Pelaccio, Dennis G.; Scheil, Christine M.; Petrosky, Lyman J.

1993-01-01

A Nuclear Thermal Propulsion (NTP) engine system design analysis tool is required to support current and future Space Exploration Initiative (SEI) propulsion and vehicle design studies. Currently available NTP engine design models are those developed during the NERVA program in the 1960's and early 1970's and are highly unique to that design or are modifications of current liquid propulsion system design models. To date, NTP engine-based liquid design models lack integrated design of key NTP engine design features in the areas of reactor, shielding, multi-propellant capability, and multi-redundant pump feed fuel systems. Additionally, since the SEI effort is in the initial development stage, a robust, verified NTP analysis design tool could be of great use to the community. This effort developed an NTP engine system design analysis program (tool), known as the Nuclear Engine System Simulation (NESS) program, to support ongoing and future engine system and stage design study efforts. In this effort, Science Applications International Corporation's (SAIC) NTP version of the Expanded Liquid Engine Simulation (ELES) program was modified extensively to include Westinghouse Electric Corporation's near-term solid-core reactor design model. The ELES program has extensive capability to conduct preliminary system design analysis of liquid rocket systems and vehicles. The program is modular in nature and is versatile in terms of modeling state-of-the-art component and system options as discussed. The Westinghouse reactor design model, which was integrated in the NESS program, is based on the near-term solid-core ENABLER NTP reactor design concept. This program is now capable of accurately modeling (characterizing) a complete near-term solid-core NTP engine system in great detail, for a number of design options, in an efficient manner. The following discussion summarizes the overall analysis methodology, key assumptions, and capabilities associated with the NESS presents an example problem, and compares the results to related NTP engine system designs. Initial installation instructions and program disks are in Volume 2 of the NESS Program User's Guide.

Web-Based Intervention for Women With Type 1 Diabetes in Pregnancy and Early Motherhood: Critical Analysis of Adherence to Technological Elements and Study Design.

PubMed

Berg, Marie; Linden, Karolina; Adolfsson, Annsofie; Sparud Lundin, Carina; Ranerup, Agneta

2018-05-02

Numerous Web-based interventions have been implemented to promote health and health-related behaviors in persons with chronic conditions. Using randomized controlled trials to evaluate such interventions creates a range of challenges, which in turn can influence the study outcome. Applying a critical perspective when evaluating Web-based health interventions is important. The objective of this study was to critically analyze and discuss the challenges of conducting a Web-based health intervention as a randomized controlled trial. The MODIAB-Web study was critically examined using an exploratory case study methodology and the framework for analysis offered through the Persuasive Systems Design model. Focus was on technology, study design, and Web-based support usage, with special focus on the forum for peer support. Descriptive statistics and qualitative content analysis were used. The persuasive content and technological elements in the design of the randomized controlled trial included all four categories of the Persuasive Systems Design model, but not all design principles were implemented. The study duration was extended to a period of four and a half years. Of 81 active participants in the intervention group, a maximum of 36 women were simultaneously active. User adherence varied greatly with a median of 91 individual log-ins. The forum for peer support was used by 63 participants. Although only about one-third of the participants interacted in the forum, there was a fairly rich exchange of experiences and advice between them. Thus, adherence in terms of social interactions was negatively affected by limited active participation due to prolonged recruitment process and randomization effects. Lessons learned from this critical analysis are that technology and study design matter and might mutually influence each other. In Web-based interventions, the use of design theories enables utilization of the full potential of technology and promotes adherence. The randomization element in a randomized controlled trial design can become a barrier to achieving a critical mass of user interactions in Web-based interventions, especially when social support is included. For extended study periods, the technology used may need to be adapted in line with newly available technical options to avoid the risk of becoming outdated in the user realm, which in turn might jeopardize study validity in terms of randomized controlled trial designs. On the basis of lessons learned in this randomized controlled trial, we give recommendations to consider when designing and evaluating Web-based health interventions. ©Marie Berg, Karolina Linden, Annsofie Adolfsson, Carina Sparud Lundin, Agneta Ranerup. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 02.05.2018.

Requirements analysis, domain knowledge, and design

NASA Technical Reports Server (NTRS)

Potts, Colin

1988-01-01

Two improvements to current requirements analysis practices are suggested: domain modeling, and the systematic application of analysis heuristics. Domain modeling is the representation of relevant application knowledge prior to requirements specification. Artificial intelligence techniques may eventually be applicable for domain modeling. In the short term, however, restricted domain modeling techniques, such as that in JSD, will still be of practical benefit. Analysis heuristics are standard patterns of reasoning about the requirements. They usually generate questions of clarification or issues relating to completeness. Analysis heuristics can be represented and therefore systematically applied in an issue-based framework. This is illustrated by an issue-based analysis of JSD's domain modeling and functional specification heuristics. They are discussed in the context of the preliminary design of simple embedded systems.

Space crew radiation exposure analysis system based on a commercial stand-alone CAD system

NASA Technical Reports Server (NTRS)

Appleby, Matthew H.; Golightly, Michael J.; Hardy, Alva C.

1992-01-01

Major improvements have recently been completed in the approach to spacecraft shielding analysis. A Computer-Aided Design (CAD)-based system has been developed for determining the shielding provided to any point within or external to the spacecraft. Shielding analysis is performed using a commercially available stand-alone CAD system and a customized ray-tracing subroutine contained within a standard engineering modeling software package. This improved shielding analysis technique has been used in several vehicle design projects such as a Mars transfer habitat, pressurized lunar rover, and the redesigned Space Station. Results of these analyses are provided to demonstrate the applicability and versatility of the system.

Multi-Mission System Analysis for Planetary Entry (M-SAPE) Version 1

NASA Technical Reports Server (NTRS)

Samareh, Jamshid; Glaab, Louis; Winski, Richard G.; Maddock, Robert W.; Emmett, Anjie L.; Munk, Michelle M.; Agrawal, Parul; Sepka, Steve; Aliaga, Jose; Zarchi, Kerry;

Probabilistic Finite Element Analysis & Design Optimization for Structural Designs

NASA Astrophysics Data System (ADS)

Deivanayagam, Arumugam

This study focuses on implementing probabilistic nature of material properties (Kevlar® 49) to the existing deterministic finite element analysis (FEA) of fabric based engine containment system through Monte Carlo simulations (MCS) and implementation of probabilistic analysis in engineering designs through Reliability Based Design Optimization (RBDO). First, the emphasis is on experimental data analysis focusing on probabilistic distribution models which characterize the randomness associated with the experimental data. The material properties of Kevlar® 49 are modeled using experimental data analysis and implemented along with an existing spiral modeling scheme (SMS) and user defined constitutive model (UMAT) for fabric based engine containment simulations in LS-DYNA. MCS of the model are performed to observe the failure pattern and exit velocities of the models. Then the solutions are compared with NASA experimental tests and deterministic results. MCS with probabilistic material data give a good prospective on results rather than a single deterministic simulation results. The next part of research is to implement the probabilistic material properties in engineering designs. The main aim of structural design is to obtain optimal solutions. In any case, in a deterministic optimization problem even though the structures are cost effective, it becomes highly unreliable if the uncertainty that may be associated with the system (material properties, loading etc.) is not represented or considered in the solution process. Reliable and optimal solution can be obtained by performing reliability optimization along with the deterministic optimization, which is RBDO. In RBDO problem formulation, in addition to structural performance constraints, reliability constraints are also considered. This part of research starts with introduction to reliability analysis such as first order reliability analysis, second order reliability analysis followed by simulation technique that are performed to obtain probability of failure and reliability of structures. Next, decoupled RBDO procedure is proposed with a new reliability analysis formulation with sensitivity analysis, which is performed to remove the highly reliable constraints in the RBDO, thereby reducing the computational time and function evaluations. Followed by implementation of the reliability analysis concepts and RBDO in finite element 2D truss problems and a planar beam problem are presented and discussed.

TADS: A CFD-based turbomachinery and analysis design system with GUI. Volume 1: Method and results

NASA Technical Reports Server (NTRS)

Topp, D. A.; Myers, R. A.; Delaney, R. A.

1995-01-01

The primary objective of this study was the development of a computational fluid dynamics (CFD) based turbomachinery airfoil analysis and design system, controlled by a graphical user interface (GUI). The computer codes resulting from this effort are referred to as the Turbomachinery Analysis and Design System (TADS). This document describes the theoretical basis and analytical results from the TADS system. TADS couples a throughflow solver (ADPAC) with a quasi-3D blade-to-blade solver (RVCQ3D) in an interactive package. Throughflow analysis capability was developed in ADPAC through the addition of blade force and blockage terms to the governing equations. A GUI was developed to simplify user input and automate the many tasks required to perform turbomachinery analysis and design. The coupling of various programs was done in a way that alternative solvers or grid generators could be easily incorporated into the TADS framework. Results of aerodynamic calculations using the TADS system are presented for a highly loaded fan, a compressor stator, a low-speed turbine blade, and a transonic turbine vane.

When paradigms collide at the road rail interface: evaluation of a sociotechnical systems theory design toolkit for cognitive work analysis.

PubMed

Read, Gemma J M; Salmon, Paul M; Lenné, Michael G

2016-09-01

The Cognitive Work Analysis Design Toolkit (CWA-DT) is a recently developed approach that provides guidance and tools to assist in applying the outputs of CWA to design processes to incorporate the values and principles of sociotechnical systems theory. In this paper, the CWA-DT is evaluated based on an application to improve safety at rail level crossings. The evaluation considered the extent to which the CWA-DT met pre-defined methodological criteria and aligned with sociotechnical values and principles. Both process and outcome measures were taken based on the ratings of workshop participants and human factors experts. Overall, workshop participants were positive about the process and indicated that it met the methodological criteria and sociotechnical values. However, expert ratings suggested that the CWA-DT achieved only limited success in producing RLX designs that fully aligned with the sociotechnical approach. Discussion about the appropriateness of the sociotechnical approach in a public safety context is provided. Practitioner Summary: Human factors and ergonomics practitioners need evidence of the effectiveness of methods. A design toolkit for cognitive work analysis, incorporating values and principles from sociotechnical systems theory, was applied to create innovative designs for rail level crossings. Evaluation results based on the application are provided and discussed.

Aerodynamic design of turbomachinery blading in three-dimensional flow - An application to radial inflow turbines

NASA Technical Reports Server (NTRS)

Yang, Y. L.; Tan, C. S.; Hawthorne, W. R.

1992-01-01

A computational method, based on a theory for turbomachinery blading design in three-dimensional inviscid flow, is applied to a parametric design study of a radial inflow turbine wheel. As the method requires the specification of swirl distribution, a technique for its smooth generation within the blade region is proposed. Excellent agreements have been obtained between the computed results from this design method and those from direct Euler computations, demonstrating the correspondence and consistency between the two. The computed results indicate the sensitivity of the pressure distribution to a lean in the stacking axis and a minor alteration in the hub/shroud profiles. Analysis based on Navier-Stokes solver shows no breakdown of flow within the designed blade passage and agreement with that from design calculation; thus the flow in the designed turbine rotor closely approximates that of an inviscid one. These calculations illustrate the use of a design method coupled to an analysis tool for establishing guidelines and criteria for designing turbomachinery blading.

Cryogenic Tank Structure Sizing With Structural Optimization Method

NASA Technical Reports Server (NTRS)

Wang, J. T.; Johnson, T. F.; Sleight, D. W.; Saether, E.

2001-01-01

Structural optimization methods in MSC /NASTRAN are used to size substructures and to reduce the weight of a composite sandwich cryogenic tank for future launch vehicles. Because the feasible design space of this problem is non-convex, many local minima are found. This non-convex problem is investigated in detail by conducting a series of analyses along a design line connecting two feasible designs. Strain constraint violations occur for some design points along the design line. Since MSC/NASTRAN uses gradient-based optimization procedures. it does not guarantee that the lowest weight design can be found. In this study, a simple procedure is introduced to create a new starting point based on design variable values from previous optimization analyses. Optimization analysis using this new starting point can produce a lower weight design. Detailed inputs for setting up the MSC/NASTRAN optimization analysis and final tank design results are presented in this paper. Approaches for obtaining further weight reductions are also discussed.

Mechanical Response Analysis of Long-life Asphalt Pavement Structure of Yunluo High-speed on the Semi-rigid Base

NASA Astrophysics Data System (ADS)

Liu, Feng; Wu, Chuanhai; Xu, Xinquan; Li, Hao; Wang, Zhixiang

2018-01-01

In order to grasp the rule of the strain change of the semi-rigid asphalt pavement structure under the FWD load and provide a reliable theoretical and practical basis for the design of the pavement structure, based on the test section of Guangdong Yunluo expressway, taking FWD as the loading tool, by using the finite element analysis software ANSYS, the internal variation rules of each pavement structural layer were obtained. Based on the results of the theoretical analysis, the measured strain sensor was set up in the corresponding layer of the pavement structure, and the strain test plan was determined. Based on the analysis of the strain data obtained from several structural layers and field monitoring, the rationality of the type pavement structure and the strain test scheme were verified, so as to provide useful help for the design and the maintenance of the pavement structure.

Design and optimization of zero-energy-consumption based solar energy residential building systems

NASA Astrophysics Data System (ADS)

Zheng, D. L.; Yu, L. J.; Tan, H. W.

2017-11-01

Energy consumption of residential buildings has grown fast in recent years, thus raising a challenge on zero energy residential building (ZERB) systems, which aim at substantially reducing energy consumption of residential buildings. Thus, how to facilitate ZERB has become a hot but difficult topic. In the paper, we put forward the overall design principle of ZERB based on analysis of the systems’ energy demand. In particular, the architecture for both schematic design and passive technology is optimized and both energy simulation analysis and energy balancing analysis are implemented, followed by committing the selection of high-efficiency appliance and renewable energy sources for ZERB residential building. In addition, Chinese classical residential building has been investigated in the proposed case, in which several critical aspects such as building optimization, passive design, PV panel and HVAC system integrated with solar water heater, Phase change materials, natural ventilation, etc., have been taken into consideration.

Global-Local Analysis and Optimization of a Composite Civil Tilt-Rotor Wing

NASA Technical Reports Server (NTRS)

Rais-Rohani, Masound

1999-01-01

This report gives highlights of an investigation on the design and optimization of a thin composite wing box structure for a civil tilt-rotor aircraft. Two different concepts are considered for the cantilever wing: (a) a thin monolithic skin design, and (b) a thick sandwich skin design. Each concept is examined with three different skin ply patterns based on various combinations of 0, +/-45, and 90 degree plies. The global-local technique is used in the analysis and optimization of the six design models. The global analysis is based on a finite element model of the wing-pylon configuration while the local analysis uses a uniformly supported plate representing a wing panel. Design allowables include those on vibration frequencies, panel buckling, and material strength. The design optimization problem is formulated as one of minimizing the structural weight subject to strength, stiffness, and d,vnamic constraints. Six different loading conditions based on three different flight modes are considered in the design optimization. The results of this investigation reveal that of all the loading conditions the one corresponding to the rolling pull-out in the airplane mode is the most stringent. Also the frequency constraints are found to drive the skin thickness limits, rendering the buckling constraints inactive. The optimum skin ply pattern for the monolithic skin concept is found to be (((0/+/-45/90/(0/90)(sub 2))(sub s))(sub s), while for the sandwich skin concept the optimal ply pattern is found to be ((0/+/-45/90)(sub 2s))(sub s).

A new design approach to MMI-based (de)multiplexers

NASA Astrophysics Data System (ADS)

Yueyu, Xiao; Sailing, He

2004-09-01

A novel design method of the wavelength (de)multiplexer is presented. The output spectral response of a (de)multiplexer is designed from the view of FIR filters. Avoiding laborious mathematic analysis, the (de)multiplexer is analyzed and designed in this explicit and simple method. A four channel (de)multiplexer based on multimode interference (MMI) is designed as an example. The result obtained agrees with that of the commonly used method, and is verified by a finite difference beam propagation method (FDBPM) simulation.

Introduction to Chemical Engineering Reactor Analysis: A Web-Based Reactor Design Game

ERIC Educational Resources Information Center

Orbey, Nese; Clay, Molly; Russell, T.W. Fraser

2014-01-01

An approach to explain chemical engineering through a Web-based interactive game design was developed and used with college freshman and junior/senior high school students. The goal of this approach was to demonstrate how to model a lab-scale experiment, and use the results to design and operate a chemical reactor. The game incorporates both…

Performance-Based Seismic Design of Steel Frames Utilizing Colliding Bodies Algorithm

PubMed Central

Veladi, H.

2014-01-01

A pushover analysis method based on semirigid connection concept is developed and the colliding bodies optimization algorithm is employed to find optimum seismic design of frame structures. Two numerical examples from the literature are studied. The results of the new algorithm are compared to the conventional design methods to show the power or weakness of the algorithm. PMID:25202717

Performance-based seismic design of steel frames utilizing colliding bodies algorithm.

PubMed

Veladi, H

2014-01-01

A pushover analysis method based on semirigid connection concept is developed and the colliding bodies optimization algorithm is employed to find optimum seismic design of frame structures. Two numerical examples from the literature are studied. The results of the new algorithm are compared to the conventional design methods to show the power or weakness of the algorithm.

Computer program for preliminary design analysis of axial-flow turbines

NASA Technical Reports Server (NTRS)

Glassman, A. J.

1972-01-01

The program method is based on a mean-diameter flow analysis. Input design requirements include power or pressure ratio, flow, temperature, pressure, and speed. Turbine designs are generated for any specified number of stages and for any of three types of velocity diagrams (symmetrical, zero exit swirl, or impulse). Exit turning vanes can be included in the design. Program output includes inlet and exit annulus dimensions, exit temperature and pressure, total and static efficiencies, blading angles, and last-stage critical velocity ratios. The report presents the analysis method, a description of input and output with sample cases, and the program listing.

Problem Solving Techniques for the Design of Algorithms.

ERIC Educational Resources Information Center

Kant, Elaine; Newell, Allen

1984-01-01

Presents model of algorithm design (activity in software development) based on analysis of protocols of two subjects designing three convex hull algorithms. Automation methods, methods for studying algorithm design, role of discovery in problem solving, and comparison of different designs of case study according to model are highlighted.…

Intuitive web-based experimental design for high-throughput biomedical data.

PubMed

Friedrich, Andreas; Kenar, Erhan; Kohlbacher, Oliver; Nahnsen, Sven

2015-01-01

Big data bioinformatics aims at drawing biological conclusions from huge and complex biological datasets. Added value from the analysis of big data, however, is only possible if the data is accompanied by accurate metadata annotation. Particularly in high-throughput experiments intelligent approaches are needed to keep track of the experimental design, including the conditions that are studied as well as information that might be interesting for failure analysis or further experiments in the future. In addition to the management of this information, means for an integrated design and interfaces for structured data annotation are urgently needed by researchers. Here, we propose a factor-based experimental design approach that enables scientists to easily create large-scale experiments with the help of a web-based system. We present a novel implementation of a web-based interface allowing the collection of arbitrary metadata. To exchange and edit information we provide a spreadsheet-based, humanly readable format. Subsequently, sample sheets with identifiers and metainformation for data generation facilities can be created. Data files created after measurement of the samples can be uploaded to a datastore, where they are automatically linked to the previously created experimental design model.

Human Resources Data in Weapon System Design: An Initial Plan for Development of a Unified Data Base.

DTIC Science & Technology

1980-11-01

Dela Bnrted) Item 19 Continued: system design design handbooks maintenance manpower simulation de’ision options cost estimating relationships prediction...determine the extent to which human resources data (HRD) are used in early system design. The third was to assess the availability and ade - quacy of...relationships, regression analysis, comparability analysis, expected value techniques) to provide initial data values in the very early stages of weapon system

Using EIGER for Antenna Design and Analysis

NASA Technical Reports Server (NTRS)

Champagne, Nathan J.; Khayat, Michael; Kennedy, Timothy F.; Fink, Patrick W.

2007-01-01

EIGER (Electromagnetic Interactions GenERalized) is a frequency-domain electromagnetics software package that is built upon a flexible framework, designed using object-oriented techniques. The analysis methods used include moment method solutions of integral equations, finite element solutions of partial differential equations, and combinations thereof. The framework design permits new analysis techniques (boundary conditions, Green#s functions, etc.) to be added to the software suite with a sensible effort. The code has been designed to execute (in serial or parallel) on a wide variety of platforms from Intel-based PCs and Unix-based workstations. Recently, new potential integration scheme s that avoid singularity extraction techniques have been added for integral equation analysis. These new integration schemes are required for facilitating the use of higher-order elements and basis functions. Higher-order elements are better able to model geometrical curvature using fewer elements than when using linear elements. Higher-order basis functions are beneficial for simulating structures with rapidly varying fields or currents. Results presented here will demonstrate curren t and future capabilities of EIGER with respect to analysis of installed antenna system performance in support of NASA#s mission of exploration. Examples include antenna coupling within an enclosed environment and antenna analysis on electrically large manned space vehicles.

Aerodynamic design optimization using sensitivity analysis and computational fluid dynamics

NASA Technical Reports Server (NTRS)

Baysal, Oktay; Eleshaky, Mohamed E.

1991-01-01

A new and efficient method is presented for aerodynamic design optimization, which is based on a computational fluid dynamics (CFD)-sensitivity analysis algorithm. The method is applied to design a scramjet-afterbody configuration for an optimized axial thrust. The Euler equations are solved for the inviscid analysis of the flow, which in turn provides the objective function and the constraints. The CFD analysis is then coupled with the optimization procedure that uses a constrained minimization method. The sensitivity coefficients, i.e. gradients of the objective function and the constraints, needed for the optimization are obtained using a quasi-analytical method rather than the traditional brute force method of finite difference approximations. During the one-dimensional search of the optimization procedure, an approximate flow analysis (predicted flow) based on a first-order Taylor series expansion is used to reduce the computational cost. Finally, the sensitivity of the optimum objective function to various design parameters, which are kept constant during the optimization, is computed to predict new optimum solutions. The flow analysis of the demonstrative example are compared with the experimental data. It is shown that the method is more efficient than the traditional methods.

Space-Based Space Surveillance Logistics Case Study: A Qualitative Product Support Element Analysis

DTIC Science & Technology

2017-12-01

Facilities and Infrastructure. Product Support Management and Design Interface are also covered, but only in a general manner. Conclusions from the study...core analysis, with the overarching two elements ( Design Interface and Product Support Management) mentioned briefly. G. THESIS STATEMENT This...were implemented. The two overarching elements of Product Support Management and Design Interface will be discussed briefly in the findings section

Alternatives for Developing User Documentation for Applications Software

DTIC Science & Technology

1991-09-01

style that is designed to match adult reading behaviors, using reader-based writing techniques, developing effective graphics , creating reference aids...involves research, analysis, design , and testing. The writer must have a solid understanding of the technical aspects of the document being prepared, good...ABSTRACT The preparation of software documentation is an iterative process that involves research, analysis, design , and testing. The writer must have

Novel Image Encryption Scheme Based on Chebyshev Polynomial and Duffing Map

PubMed Central

2014-01-01

We present a novel image encryption algorithm using Chebyshev polynomial based on permutation and substitution and Duffing map based on substitution. Comprehensive security analysis has been performed on the designed scheme using key space analysis, visual testing, histogram analysis, information entropy calculation, correlation coefficient analysis, differential analysis, key sensitivity test, and speed test. The study demonstrates that the proposed image encryption algorithm shows advantages of more than 10113 key space and desirable level of security based on the good statistical results and theoretical arguments. PMID:25143970

Computational electronics and electromagnetics

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

Shang, C C

The Computational Electronics and Electromagnetics thrust area serves as the focal point for Engineering R and D activities for developing computer-based design and analysis tools. Representative applications include design of particle accelerator cells and beamline components; design of transmission line components; engineering analysis and design of high-power (optical and microwave) components; photonics and optoelectronics circuit design; electromagnetic susceptibility analysis; and antenna synthesis. The FY-97 effort focuses on development and validation of (1) accelerator design codes; (2) 3-D massively parallel, time-dependent EM codes; (3) material models; (4) coupling and application of engineering tools for analysis and design of high-power components; andmore » (5) development of beam control algorithms coupled to beam transport physics codes. These efforts are in association with technology development in the power conversion, nondestructive evaluation, and microtechnology areas. The efforts complement technology development in Lawrence Livermore National programs.« less

CometBoards Users Manual Release 1.0

NASA Technical Reports Server (NTRS)

Guptill, James D.; Coroneos, Rula M.; Patnaik, Surya N.; Hopkins, Dale A.; Berke, Lazlo

1996-01-01

Several nonlinear mathematical programming algorithms for structural design applications are available at present. These include the sequence of unconstrained minimizations technique, the method of feasible directions, and the sequential quadratic programming technique. The optimality criteria technique and the fully utilized design concept are two other structural design methods. A project was undertaken to bring all these design methods under a common computer environment so that a designer can select any one of these tools that may be suitable for his/her application. To facilitate selection of a design algorithm, to validate and check out the computer code, and to ascertain the relative merits of the design tools, modest finite element structural analysis programs based on the concept of stiffness and integrated force methods have been coupled to each design method. The code that contains both these design and analysis tools, by reading input information from analysis and design data files, can cast the design of a structure as a minimum-weight optimization problem. The code can then solve it with a user-specified optimization technique and a user-specified analysis method. This design code is called CometBoards, which is an acronym for Comparative Evaluation Test Bed of Optimization and Analysis Routines for the Design of Structures. This manual describes for the user a step-by-step procedure for setting up the input data files and executing CometBoards to solve a structural design problem. The manual includes the organization of CometBoards; instructions for preparing input data files; the procedure for submitting a problem; illustrative examples; and several demonstration problems. A set of 29 structural design problems have been solved by using all the optimization methods available in CometBoards. A summary of the optimum results obtained for these problems is appended to this users manual. CometBoards, at present, is available for Posix-based Cray and Convex computers, Iris and Sun workstations, and the VM/CMS system.

Subscale and Full-Scale Testing of Buckling-Critical Launch Vehicle Shell Structures

NASA Technical Reports Server (NTRS)

Hilburger, Mark W.; Haynie, Waddy T.; Lovejoy, Andrew E.; Roberts, Michael G.; Norris, Jeffery P.; Waters, W. Allen; Herring, Helen M.

2012-01-01

New analysis-based shell buckling design factors (aka knockdown factors), along with associated design and analysis technologies, are being developed by NASA for the design of launch vehicle structures. Preliminary design studies indicate that implementation of these new knockdown factors can enable significant reductions in mass and mass-growth in these vehicles and can help mitigate some of NASA s launch vehicle development and performance risks by reducing the reliance on testing, providing high-fidelity estimates of structural performance, reliability, robustness, and enable increased payload capability. However, in order to validate any new analysis-based design data or methods, a series of carefully designed and executed structural tests are required at both the subscale and full-scale level. This paper describes recent buckling test efforts at NASA on two different orthogrid-stiffened metallic cylindrical shell test articles. One of the test articles was an 8-ft-diameter orthogrid-stiffened cylinder and was subjected to an axial compression load. The second test article was a 27.5-ft-diameter Space Shuttle External Tank-derived cylinder and was subjected to combined internal pressure and axial compression.

Repair Concepts as Design Constraints of a Stiffened Composite PRSEUS Panel

NASA Technical Reports Server (NTRS)

Przekop, Adam

2012-01-01

A design and analysis of a repair concept applicable to a stiffened thin-skin composite panel based on the Pultruded Rod Stitched Efficient Unitized Structure is presented. The concept is a bolted repair using metal components, so that it can easily be applied in the operational environment. The damage scenario considered is a midbay-to-midbay saw-cut with a severed stiffener, flange and skin. In a previous study several repair configurations were explored and their feasibility confirmed but refinement was needed. The present study revisits the problem under recently revised design requirements and broadens the suite of loading conditions considered. The repair assembly design is based on the critical tension loading condition and subsequently its robustness is verified for a pressure loading case. High fidelity modeling techniques such as mesh-independent definition of compliant fasteners, elastic-plastic material properties for metal parts and geometrically nonlinear solutions are utilized in the finite element analysis. The best repair design is introduced, its analysis results are presented and factors influencing the design are assessed and discussed.

Analysis of material parameter effects on fluidlastic isolators performance

NASA Astrophysics Data System (ADS)

Cheng, Q. Y.; Deng, J. H.; Feng, Z. Z.; Qian, F.

2018-01-01

Control of vibration in helicopters has always been a complex and challenging task. The fluidlastic isolators become more and more widely used because the fluids are non-toxic, non-corrosive, nonflammable, and compatible with most elastomers and adhesives. In the field of the fluidlastic isolators design, the selection of design parameters of fluid and rubber is very important to obtain efficient vibration-suppressed. Aiming at getting the property of fluidlastic isolator to material design parameters, a dynamic equation is set up based on the dynamic theory. And the dynamic analysis is carried out. The influences of design parameters on the property of fluidlastic isolator are calculated. The material parameters examined are the properties of fluid and rubber. Analysis results showed that the design parameters such as density of fluid, viscosity coefficient of fluid, stiffness of rubber (K1) and loss coefficient of rubber have obvious influence on the performance of isolator. Base on the results of the study it is concluded that the efficient vibration-suppressed can be obtained by the selection of design parameters.

Design of tubesheet for U-tube heat exchangers

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

Paliwal, D.N.; Saxena, R.M.

1993-02-01

Thorough analysis of two-side integral tubesheet of U-tube heat exchanger is carried out, using Panc's component theory of plates. Effects of solid annular rim and interaction between tubesheet and shell/channel are considered. A design procedure based on foregoing analysis is proposed. Fictive elastic constants due to Osweiller, as well as effective elastic constants due to Slot and O'Donnell, are employed. Deformations, internal forces and primary stress intensities are evaluated in both pitch and diagonal directions. Stress category concept of ASME Sect. VIII Div. 2 is used. Design thickness obtained by this method is compared with the thicknesses calculated, using ASMEmore » Sect. VIII Div. 1, TEMA and BS-5500. This method enables us to calculate stresses in shell and channel in the junction region as well. Present analysis and design procedure thoroughly investigates the tubesheet behavior and leads to a thinner tubesheet. It is concluded that though all the codes based on Gardner's work provide safe and efficient design rules, and lie on firm footing, still there is further scope for reducing the design thickness of tubesheet by about ten percent.« less

Optimal Parameter Design of Coarse Alignment for Fiber Optic Gyro Inertial Navigation System.

PubMed

Lu, Baofeng; Wang, Qiuying; Yu, Chunmei; Gao, Wei

2015-06-25

Two different coarse alignment algorithms for Fiber Optic Gyro (FOG) Inertial Navigation System (INS) based on inertial reference frame are discussed in this paper. Both of them are based on gravity vector integration, therefore, the performance of these algorithms is determined by integration time. In previous works, integration time is selected by experience. In order to give a criterion for the selection process, and make the selection of the integration time more accurate, optimal parameter design of these algorithms for FOG INS is performed in this paper. The design process is accomplished based on the analysis of the error characteristics of these two coarse alignment algorithms. Moreover, this analysis and optimal parameter design allow us to make an adequate selection of the most accurate algorithm for FOG INS according to the actual operational conditions. The analysis and simulation results show that the parameter provided by this work is the optimal value, and indicate that in different operational conditions, the coarse alignment algorithms adopted for FOG INS are different in order to achieve better performance. Lastly, the experiment results validate the effectiveness of the proposed algorithm.

Space Launch System Base Heating Test: Sub-Scale Rocket Engine/Motor Design, Development and Performance Analysis

NASA Technical Reports Server (NTRS)

Mehta, Manish; Seaford, Mark; Kovarik, Brian; Dufrene, Aaron; Solly, Nathan; Kirchner, Robert; Engel, Carl D.

2014-01-01

The Space Launch System (SLS) base heating test is broken down into two test programs: (1) Pathfinder and (2) Main Test. The Pathfinder Test Program focuses on the design, development, hot-fire test and performance analyses of the 2% sub-scale SLS core-stage and booster element propulsion systems. The core-stage propulsion system is composed of four gaseous oxygen/hydrogen RS-25D model engines and the booster element is composed of two aluminum-based model solid rocket motors (SRMs). The first section of the paper discusses the motivation and test facility specifications for the test program. The second section briefly investigates the internal flow path of the design. The third section briefly shows the performance of the model RS-25D engines and SRMs for the conducted short duration hot-fire tests. Good agreement is observed based on design prediction analysis and test data. This program is a challenging research and development effort that has not been attempted in 40+ years for a NASA vehicle.

ACSYNT - A standards-based system for parametric, computer aided conceptual design of aircraft

NASA Technical Reports Server (NTRS)

Jayaram, S.; Myklebust, A.; Gelhausen, P.

1992-01-01

A group of eight US aerospace companies together with several NASA and NAVY centers, led by NASA Ames Systems Analysis Branch, and Virginia Tech's CAD Laboratory agreed, through the assistance of Americal Technology Initiative, in 1990 to form the ACSYNT (Aircraft Synthesis) Institute. The Institute is supported by a Joint Sponsored Research Agreement to continue the research and development in computer aided conceptual design of aircraft initiated by NASA Ames Research Center and Virginia Tech's CAD Laboratory. The result of this collaboration, a feature-based, parametric computer aided aircraft conceptual design code called ACSYNT, is described. The code is based on analysis routines begun at NASA Ames in the early 1970's. ACSYNT's CAD system is based entirely on the ISO standard Programmer's Hierarchical Interactive Graphics System and is graphics-device independent. The code includes a highly interactive graphical user interface, automatically generated Hermite and B-Spline surface models, and shaded image displays. Numerous features to enhance aircraft conceptual design are described.

Shape memory alloy smart knee spacer to enhance knee functionality: model design and finite element analysis.

PubMed

Gautam, Arvind; Rani, A Bhargavi; Callejas, Miguel A; Acharyya, Swati Ghosh; Acharyya, Amit; Biswas, Dwaipayan; Bhandari, Vasundhra; Sharma, Paresh; Naik, Ganesh R

2016-08-01

In this paper we introduce Shape Memory Alloy (SMA) for designing the tibial part of Total Knee Arthroplasty (TKA) by exploiting the shape-memory and pseudo-elasticity property of the SMA (e.g. NiTi). This would eliminate the drawbacks of the state-of-the art PMMA based knee-spacer including fracture, sustainability, dislocation, tilting, translation and subluxation for tackling the Osteoarthritis especially for the aged people of 45-plus or the athletes. In this paper a Computer Aided Design (CAD) model using SolidWorks for the knee-spacer is presented based on the proposed SMA adopting the state-of-the art industry-standard geometry that is used in the PMMA based spacer design. Subsequently Ansys based Finite Element Analysis is carried out to measure and compare the performance between the proposed SMA based model with the state-of-the art PMMA ones. 81% more bending is noticed in the PMMA based spacer compared to the proposed SMA that would eventually cause fracture and tilting or translation of spacer. Permanent shape deformation of approximately 58.75% in PMMA based spacer is observed compared to recoverable 11% deformation in SMA when same load is applied on both separately.

Conceptual Design Oriented Wing Structural Analysis and Optimization

NASA Technical Reports Server (NTRS)

Lau, May Yuen

1996-01-01

Airplane optimization has always been the goal of airplane designers. In the conceptual design phase, a designer's goal could be tradeoffs between maximum structural integrity, minimum aerodynamic drag, or maximum stability and control, many times achieved separately. Bringing all of these factors into an iterative preliminary design procedure was time consuming, tedious, and not always accurate. For example, the final weight estimate would often be based upon statistical data from past airplanes. The new design would be classified based on gross characteristics, such as number of engines, wingspan, etc., to see which airplanes of the past most closely resembled the new design. This procedure works well for conventional airplane designs, but not very well for new innovative designs. With the computing power of today, new methods are emerging for the conceptual design phase of airplanes. Using finite element methods, computational fluid dynamics, and other computer techniques, designers can make very accurate disciplinary-analyses of an airplane design. These tools are computationally intensive, and when used repeatedly, they consume a great deal of computing time. In order to reduce the time required to analyze a design and still bring together all of the disciplines (such as structures, aerodynamics, and controls) into the analysis, simplified design computer analyses are linked together into one computer program. These design codes are very efficient for conceptual design. The work in this thesis is focused on a finite element based conceptual design oriented structural synthesis capability (CDOSS) tailored to be linked into ACSYNT.

Statistical power and optimal design in experiments in which samples of participants respond to samples of stimuli.

PubMed

Westfall, Jacob; Kenny, David A; Judd, Charles M

2014-10-01

Researchers designing experiments in which a sample of participants responds to a sample of stimuli are faced with difficult questions about optimal study design. The conventional procedures of statistical power analysis fail to provide appropriate answers to these questions because they are based on statistical models in which stimuli are not assumed to be a source of random variation in the data, models that are inappropriate for experiments involving crossed random factors of participants and stimuli. In this article, we present new methods of power analysis for designs with crossed random factors, and we give detailed, practical guidance to psychology researchers planning experiments in which a sample of participants responds to a sample of stimuli. We extensively examine 5 commonly used experimental designs, describe how to estimate statistical power in each, and provide power analysis results based on a reasonable set of default parameter values. We then develop general conclusions and formulate rules of thumb concerning the optimal design of experiments in which a sample of participants responds to a sample of stimuli. We show that in crossed designs, statistical power typically does not approach unity as the number of participants goes to infinity but instead approaches a maximum attainable power value that is possibly small, depending on the stimulus sample. We also consider the statistical merits of designs involving multiple stimulus blocks. Finally, we provide a simple and flexible Web-based power application to aid researchers in planning studies with samples of stimuli.

Shell Buckling Design Criteria Based on Manufacturing Imperfection Signatures

NASA Technical Reports Server (NTRS)

Hilburger, Mark W.; Nemeth, Michael P.; Starnes, James H., Jr.

2004-01-01

An analysis-based approach .for developing shell-buckling design criteria for laminated-composite cylindrical shells that accurately accounts for the effects of initial geometric imperfections is presented. With this approach, measured initial geometric imperfection data from six graphite-epoxy shells are used to determine a manufacturing-process-specific imperfection signature for these shells. This imperfection signature is then used as input into nonlinear finite-element analyses. The imperfection signature represents a "first-approximation" mean imperfection shape that is suitable for developing preliminary-design data. Comparisons of test data and analytical results obtained by using several different imperfection shapes are presented for selected shells. Overall, the results indicate that the analysis-based approach presented for developing reliable preliminary-design criteria has the potential to provide improved, less conservative buckling-load estimates, and to reduce the weight and cost of developing buckling-resistant shell structures.

Modeling eye gaze patterns in clinician-patient interaction with lag sequential analysis.

PubMed

Montague, Enid; Xu, Jie; Chen, Ping-Yu; Asan, Onur; Barrett, Bruce P; Chewning, Betty

2011-10-01

The aim of this study was to examine whether lag sequential analysis could be used to describe eye gaze orientation between clinicians and patients in the medical encounter. This topic is particularly important as new technologies are implemented into multiuser health care settings in which trust is critical and nonverbal cues are integral to achieving trust. This analysis method could lead to design guidelines for technologies and more effective assessments of interventions. Nonverbal communication patterns are important aspects of clinician-patient interactions and may affect patient outcomes. The eye gaze behaviors of clinicians and patients in 110 videotaped medical encounters were analyzed using the lag sequential method to identify significant behavior sequences. Lag sequential analysis included both event-based lag and time-based lag. Results from event-based lag analysis showed that the patient's gaze followed that of the clinician, whereas the clinician's gaze did not follow the patient's. Time-based sequential analysis showed that responses from the patient usually occurred within 2 s after the initial behavior of the clinician. Our data suggest that the clinician's gaze significantly affects the medical encounter but that the converse is not true. Findings from this research have implications for the design of clinical work systems and modeling interactions. Similar research methods could be used to identify different behavior patterns in clinical settings (physical layout, technology, etc.) to facilitate and evaluate clinical work system designs.

Modeling Eye Gaze Patterns in Clinician-Patient Interaction with Lag Sequential Analysis

PubMed Central

Montague, E; Xu, J; Asan, O; Chen, P; Chewning, B; Barrett, B

2011-01-01

Objective The aim of this study was to examine whether lag-sequential analysis could be used to describe eye gaze orientation between clinicians and patients in the medical encounter. This topic is particularly important as new technologies are implemented into multi-user health care settings where trust is critical and nonverbal cues are integral to achieving trust. This analysis method could lead to design guidelines for technologies and more effective assessments of interventions. Background Nonverbal communication patterns are important aspects of clinician-patient interactions and may impact patient outcomes. Method Eye gaze behaviors of clinicians and patients in 110-videotaped medical encounters were analyzed using the lag-sequential method to identify significant behavior sequences. Lag-sequential analysis included both event-based lag and time-based lag. Results Results from event-based lag analysis showed that the patients’ gaze followed that of clinicians, while clinicians did not follow patients. Time-based sequential analysis showed that responses from the patient usually occurred within two seconds after the initial behavior of the clinician. Conclusion Our data suggest that the clinician’s gaze significantly affects the medical encounter but not the converse. Application Findings from this research have implications for the design of clinical work systems and modeling interactions. Similar research methods could be used to identify different behavior patterns in clinical settings (physical layout, technology, etc.) to facilitate and evaluate clinical work system designs. PMID:22046723

Metrological analysis of a virtual flowmeter-based transducer for cryogenic helium

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

Arpaia, P., E-mail: pasquale.arpaia@unina.it; Technology Department, European Organization for Nuclear Research; Girone, M., E-mail: mario.girone@cern.ch

2015-12-15

The metrological performance of a virtual flowmeter-based transducer for monitoring helium under cryogenic conditions is assessed. At this aim, an uncertainty model of the transducer, mainly based on a valve model, exploiting finite-element approach, and a virtual flowmeter model, based on the Sereg-Schlumberger method, are presented. The models are validated experimentally on a case study for helium monitoring in cryogenic systems at the European Organization for Nuclear Research (CERN). The impact of uncertainty sources on the transducer metrological performance is assessed by a sensitivity analysis, based on statistical experiment design and analysis of variance. In this way, the uncertainty sourcesmore » most influencing metrological performance of the transducer are singled out over the input range as a whole, at varying operating and setting conditions. This analysis turns out to be important for CERN cryogenics operation because the metrological design of the transducer is validated, and its components and working conditions with critical specifications for future improvements are identified.« less

Interaction Pattern Analysis in cMOOCs Based on the Connectivist Interaction and Engagement Framework

ERIC Educational Resources Information Center

Wang, Zhijun; Anderson, Terry; Chen, Li; Barbera, Elena

2017-01-01

Connectivist learning is interaction-centered learning. A framework describing interaction and cognitive engagement in connectivist learning was constructed using logical reasoning techniques. The framework and analysis was designed to help researchers and learning designers understand and adapt the characteristics and principles of interaction in…

Multiobjective robust design of the double wishbone suspension system based on particle swarm optimization.

PubMed

Cheng, Xianfu; Lin, Yuqun

2014-01-01

The performance of the suspension system is one of the most important factors in the vehicle design. For the double wishbone suspension system, the conventional deterministic optimization does not consider any deviations of design parameters, so design sensitivity analysis and robust optimization design are proposed. In this study, the design parameters of the robust optimization are the positions of the key points, and the random factors are the uncertainties in manufacturing. A simplified model of the double wishbone suspension is established by software ADAMS. The sensitivity analysis is utilized to determine main design variables. Then, the simulation experiment is arranged and the Latin hypercube design is adopted to find the initial points. The Kriging model is employed for fitting the mean and variance of the quality characteristics according to the simulation results. Further, a particle swarm optimization method based on simple PSO is applied and the tradeoff between the mean and deviation of performance is made to solve the robust optimization problem of the double wishbone suspension system.

Optical system design, analysis, and production for advanced technology systems; Proceedings of the Meeting, Innsbruck, Austria, Apr. 15-17, 1986

NASA Technical Reports Server (NTRS)

Fischer, Robert E. (Editor); Rogers, Philip J. (Editor)

1986-01-01

The present conference considers topics in the fields of optical systems design software, the design and analysis of optical systems, illustrative cases of advanced optical system design, the integration of optical designs into greater systems, and optical fabrication and testing techniques. Attention is given to an extended range diffraction-based merit function for lens design optimization, an assessment of technologies for stray light control and evaluation, the automated characterization of IR systems' spatial resolution, a spectrum of design techniques based on aberration theory, a three-field IR telescope, a large aperture zoom lens for 16-mm motion picture cameras, and the use of concave holographic gratings as monochomators. Also discussed are the use of aspherics in optical systems, glass choice procedures for periscope design, the fabrication and testing of unconventional optics, low mass mirrors for large optics, and the diamond grinding of optical surfaces on aspheric lens molds.

Integrating opto-thermo-mechanical design tools: open engineering's project presentation

NASA Astrophysics Data System (ADS)

De Vincenzo, P.; Klapka, Igor

2017-11-01

An integrated numerical simulation package dedicated to the analysis of the coupled interactions of optical devices is presented. To reduce human interventions during data transfers, it is based on in-memory communications between the structural analysis software OOFELIE and the optical design application ZEMAX. It allows the automated enhancement of the existing optical design with information related to the deformations of optical surfaces due to thermomechanical solicitations. From the knowledge of these deformations, a grid of points or a decomposition based on Zernike polynomials can be generated for each surface. These data are then applied to the optical design. Finally, indicators can be retrieved from ZEMAX in order to compare the optical performances with those of the system in its nominal configuration.

Engineering Analysis Using a Web-based Protocol

NASA Technical Reports Server (NTRS)

Schoeffler, James D.; Claus, Russell W.

2002-01-01

This paper reviews the development of a web-based framework for engineering analysis. A one-dimensional, high-speed analysis code called LAPIN was used in this study, but the approach can be generalized to any engineering analysis tool. The web-based framework enables users to store, retrieve, and execute an engineering analysis from a standard web-browser. We review the encapsulation of the engineering data into the eXtensible Markup Language (XML) and various design considerations in the storage and retrieval of application data.

Novel quantum well gallium arsenide-based lasers for all transmission windows in optical communication

NASA Astrophysics Data System (ADS)

Tansu, Nelson

The thesis covers the development of novel active regions for high-performance edge-emitting lasers (EEL) and vertical cavity surface-emitting lasers (VCSELs) in optical communication. Three main themes of the thesis cover the design, fabrication, and physics of the novel and alternative active regions for GaAs-based VCSELs for the three optical communications windows at wavelength regimes of 850-nm, 1300-nm, and 1500-nm, with the emphases on the 1300-nm InGaAsN QW GaAs-based active regions and on the novel design of 1500-nm GaAs-based active regions. The studies include the utilization of compressively-strained InGaAsP quantum well (QW) active regions for the 850-nm VCSELs. The research on the long-wavelength lasers covers the design, growth, temperature analysis, carrier transport, and gain analysis of the InGaAsN (lambda = 1.3 mum) quantum well lasers. The novel and original design of the GaAsSb-(In)GaAsN type-II QWs to achieve 1500--3000 nm GaAs-based active regions is discussed in detail.

New method for designing serial resonant power converters

NASA Astrophysics Data System (ADS)

Hinov, Nikolay

2017-12-01

In current work is presented one comprehensive method for design of serial resonant energy converters. The method is based on new simplified approach in analysis of such kind power electronic devices. It is grounded on supposing resonant mode of operation when finding relation between input and output voltage regardless of other operational modes (when controlling frequency is below or above resonant frequency). This approach is named `quasiresonant method of analysis', because it is based on assuming that all operational modes are `sort of' resonant modes. An estimation of error was made because of the a.m. hypothesis and is compared to the classic analysis. The `quasiresonant method' of analysis gains two main advantages: speed and easiness in designing of presented power circuits. Hence it is very useful in practice and in teaching Power Electronics. Its applicability is proven with mathematic modelling and computer simulation.

[Design and Analysis of CT High-speed Data Transmission Rotating Connector Ring System Retaining Ring].

PubMed

Pan, Li; Cao, Jujiang; Liu, Min; Fu, Weiwei

2017-11-30

High speed data transmission rotating connector system for signal high-speed transmission used in the fixed end and rotating end, it is one of the core component in the CT system. This paper involves structure design and analysis of the retaining ring in the CT high speed data transmission rotating connector system based on the principle of off-axis free space optical transmission. According to the problem of the actual engineering application of space limitations, optical fiber fixed and collimator installation location, we designed the structure of the retaining ring. Using the static analysis function of ANSYS Workbench, it verifies rationality and safety of the strength of retaining ring structure. And based on modal analysis function of ANSYS Workbench, it evaluates the effect of the retaining ring on the stability of the system date transmission, and provides theoretical basis for the feasibility of the structure in practical application.

Reliability based design of the primary structure of oil tankers

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

Casella, G.; Dogliani, M.; Guedes Soares, C.

1996-12-31

The present paper describes the reliability analysis carried out for two oil tanker-ships having comparable dimensions but different design. The scope of the analysis was to derive indications on the value of the reliability index obtained for existing, typical and well designed oil tankers, as well as to apply the tentative rule checking formulation developed within the CEC-funded SHIPREL Project. The checking formula was adopted to redesign the midships section of one of the considered ships, upgrading her in order to meet the target failure probability considered in the rule development process. The resulting structure, in view of an upgradingmore » of the steel grade in the central part of the deck, lead to a convenient reliability level. The results of the analysis clearly showed that a large scatter exists presently in the design safety levels of ships, even when the Classification Societies` unified requirements are satisfied. A reliability based approach for the calibration of the rules for the global strength of ships is therefore proposed, in order to assist designers and Classification Societies in the process of producing ships which are more optimized, with respect to ensured safety levels. Based on the work reported in the paper, the feasibility and usefulness of a reliability based approach in the development of ship longitudinal strength requirements has been demonstrated.« less

Computer-aided drug design for AMP-activated protein kinase activators.

PubMed

Wang, Zhanli; Huo, Jianxin; Sun, Lidan; Wang, Yongfu; Jin, Hongwei; Yu, Hui; Zhang, Liangren; Zhou, Lishe

2011-09-01

AMP-activated protein kinase (AMPK) is an important therapeutic target for the potential treatment of metabolic disorders, cardiovascular disease and cancer. Recently, various classes of compounds that activate AMPK by direct or indirect interactions have been reported. The importance of computer-aided drug design approaches in the search for potent activators of AMPK is now established, including structure-based design, ligand-based design, fragment-based design, as well as structural analysis. This review article highlights the computer-aided drug design approaches utilized to discover of activators targeting AMPK. The principles, advantages or limitation of the different methods are also being discussed together with examples of applications taken from the literatures.

General specifications for the development of a USL NASA PC R and D statistical analysis support package

NASA Technical Reports Server (NTRS)

Dominick, Wayne D. (Editor); Bassari, Jinous; Triantafyllopoulos, Spiros

1984-01-01

The University of Southwestern Louisiana (USL) NASA PC R and D statistical analysis support package is designed to be a three-level package to allow statistical analysis for a variety of applications within the USL Data Base Management System (DBMS) contract work. The design addresses usage of the statistical facilities as a library package, as an interactive statistical analysis system, and as a batch processing package.

Automatic differentiation for design sensitivity analysis of structural systems using multiple processors

NASA Technical Reports Server (NTRS)

Nguyen, Duc T.; Storaasli, Olaf O.; Qin, Jiangning; Qamar, Ramzi

1994-01-01

An automatic differentiation tool (ADIFOR) is incorporated into a finite element based structural analysis program for shape and non-shape design sensitivity analysis of structural systems. The entire analysis and sensitivity procedures are parallelized and vectorized for high performance computation. Small scale examples to verify the accuracy of the proposed program and a medium scale example to demonstrate the parallel vector performance on multiple CRAY C90 processors are included.

ATLAS, an integrated structural analysis and design system. Volume 2: System design document

NASA Technical Reports Server (NTRS)

Erickson, W. J. (Editor)

1979-01-01

ATLAS is a structural analysis and design system, operational on the Control Data Corporation 6600/CYBER computers. The overall system design, the design of the individual program modules, and the routines in the ATLAS system library are described. The overall design is discussed in terms of system architecture, executive function, data base structure, user program interfaces and operational procedures. The program module sections include detailed code description, common block usage and random access file usage. The description of the ATLAS program library includes all information needed to use these general purpose routines.

Analysis of the implementation of ergonomic design at the new units of an oil refinery.

PubMed

Passero, Carolina Reich Marcon; Ogasawara, Erika Lye; Baú, Lucy Mara Silva; Buso, Sandro Artur; Bianchi, Marcos Cesar

2012-01-01

Ergonomic design is the adaptation of working conditions to human limitations and skills in the physical design phase of a new installation, a new working system, or new products or tools. Based on this concept, the purpose of this work was to analyze the implementation of ergonomic design at the new industrial units of an oil refinery, using the method of Ergonomic Workplace Assessment. This study was conducted by a multidisciplinary team composed of operation, maintenance and industrial safety technicians, ergonomists, designers and engineers. The analysis involved 6 production units, 1 industrial wastewater treatment unit, and 3 utilities units, all in the design detailing phase, for which 455 ergonomic requirements were identified. An analysis and characterization of the requirements identified for 5 of the production units, involving a total of 246 items, indicated that 62% were related to difficult access and blockage operations, while 15% were related to difficulties in the circulation of employees inside the units. Based on these data, it was found that the ergonomic requirements identified in the design detailing phase of an industrial unit involve physical ergonomics, and that it is very difficult to identify requirements related to organizational or cognitive ergonomics.

Improving the Aircraft Design Process Using Web-Based Modeling and Simulation

NASA Technical Reports Server (NTRS)

Reed, John A.; Follen, Gregory J.; Afjeh, Abdollah A.; Follen, Gregory J. (Technical Monitor)

2000-01-01

Designing and developing new aircraft systems is time-consuming and expensive. Computational simulation is a promising means for reducing design cycle times, but requires a flexible software environment capable of integrating advanced multidisciplinary and multifidelity analysis methods, dynamically managing data across heterogeneous computing platforms, and distributing computationally complex tasks. Web-based simulation, with its emphasis on collaborative composition of simulation models, distributed heterogeneous execution, and dynamic multimedia documentation, has the potential to meet these requirements. This paper outlines the current aircraft design process, highlighting its problems and complexities, and presents our vision of an aircraft design process using Web-based modeling and simulation.

Improving the Aircraft Design Process Using Web-based Modeling and Simulation

NASA Technical Reports Server (NTRS)

Reed, John A.; Follen, Gregory J.; Afjeh, Abdollah A.

2003-01-01

Designing and developing new aircraft systems is time-consuming and expensive. Computational simulation is a promising means for reducing design cycle times, but requires a flexible software environment capable of integrating advanced multidisciplinary and muitifidelity analysis methods, dynamically managing data across heterogeneous computing platforms, and distributing computationally complex tasks. Web-based simulation, with its emphasis on collaborative composition of simulation models, distributed heterogeneous execution, and dynamic multimedia documentation, has the potential to meet these requirements. This paper outlines the current aircraft design process, highlighting its problems and complexities, and presents our vision of an aircraft design process using Web-based modeling and simulation.

Experimental design and quantitative analysis of microbial community multiomics.

PubMed

Mallick, Himel; Ma, Siyuan; Franzosa, Eric A; Vatanen, Tommi; Morgan, Xochitl C; Huttenhower, Curtis

2017-11-30

Studies of the microbiome have become increasingly sophisticated, and multiple sequence-based, molecular methods as well as culture-based methods exist for population-scale microbiome profiles. To link the resulting host and microbial data types to human health, several experimental design considerations, data analysis challenges, and statistical epidemiological approaches must be addressed. Here, we survey current best practices for experimental design in microbiome molecular epidemiology, including technologies for generating, analyzing, and integrating microbiome multiomics data. We highlight studies that have identified molecular bioactives that influence human health, and we suggest steps for scaling translational microbiome research to high-throughput target discovery across large populations.

Coal-Based Fuel-Cell Powerplants

NASA Technical Reports Server (NTRS)

Ferral, J. F.; Pappano, A. W.; Jennings, C. N.

1986-01-01

Report assesses advanced technologyy design alternatives for integrated coal-gasifier/fuel-cell powerplants. Various gasifier, cleanup, and fuelcell options evaluated. Evaluation includes adjustments to assumed performances and costs of proposed technologies where required. Analysis identifies uncertainties remaining in designs and most promising alternatives and research and development required to develop these technologies. Bulk of report summary and detailed analysis of six major conceptual designs and variations of each. All designs for plant that uses Illinois No. 6 coal and produces 675 MW of net power.

Flat-plate photovoltaic array design optimization

NASA Technical Reports Server (NTRS)

Ross, R. G., Jr.

1980-01-01

An analysis is presented which integrates the results of specific studies in the areas of photovoltaic structural design optimization, optimization of array series/parallel circuit design, thermal design optimization, and optimization of environmental protection features. The analysis is based on minimizing the total photovoltaic system life-cycle energy cost including repair and replacement of failed cells and modules. This approach is shown to be a useful technique for array optimization, particularly when time-dependent parameters such as array degradation and maintenance are involved.

On Intelligent Design and Planning Method of Process Route Based on Gun Breech Machining Process

NASA Astrophysics Data System (ADS)

Hongzhi, Zhao; Jian, Zhang

2018-03-01

The paper states an approach of intelligent design and planning of process route based on gun breech machining process, against several problems, such as complex machining process of gun breech, tedious route design and long period of its traditional unmanageable process route. Based on gun breech machining process, intelligent design and planning system of process route are developed by virtue of DEST and VC++. The system includes two functional modules--process route intelligent design and its planning. The process route intelligent design module, through the analysis of gun breech machining process, summarizes breech process knowledge so as to complete the design of knowledge base and inference engine. And then gun breech process route intelligently output. On the basis of intelligent route design module, the final process route is made, edited and managed in the process route planning module.

An efficient current-based logic cell model for crosstalk delay analysis

NASA Astrophysics Data System (ADS)

Nazarian, Shahin; Das, Debasish

2013-04-01

Logic cell modelling is an important component in the analysis and design of CMOS integrated circuits, mostly due to nonlinear behaviour of CMOS cells with respect to the voltage signal at their input and output pins. A current-based model for CMOS logic cells is presented, which can be used for effective crosstalk noise and delta delay analysis in CMOS VLSI circuits. Existing current source models are expensive and need a new set of Spice-based characterisation, which is not compatible with typical EDA tools. In this article we present Imodel, a simple nonlinear logic cell model that can be derived from the typical cell libraries such as NLDM, with accuracy much higher than NLDM-based cell delay models. In fact, our experiments show an average error of 3% compared to Spice. This level of accuracy comes with a maximum runtime penalty of 19% compared to NLDM-based cell delay models on medium-sized industrial designs.

The Development of a Web-Based Virtual Environment for Teaching Qualitative Analysis of Structures

ERIC Educational Resources Information Center

O'Dwyer, D. W.; Logan-Phelan, T. M.; O'Neill, E. A.

2007-01-01

The current paper describes the design and development of a qualitative analysis course and an interactive web-based teaching and assessment tool called VSE (virtual structural environment). The widespread reliance on structural analysis programs requires engineers to be able to verify computer output by carrying out qualitative analyses.…

Building a Practical Natural Laminar Flow Design Capability

NASA Technical Reports Server (NTRS)

Campbell, Richard L.; Lynde, Michelle N.

2017-01-01

A preliminary natural laminar flow (NLF) design method that has been developed and applied to supersonic and transonic wings with moderate-to-high leading-edge sweeps at flight Reynolds numbers is further extended and evaluated in this paper. The modular design approach uses a knowledge-based design module linked with different flow solvers and boundary layer stability analysis methods to provide a multifidelity capability for NLF analysis and design. An assessment of the effects of different options for stability analysis is included using pressures and geometry from an NLF wing designed for the Common Research Model (CRM). Several extensions to the design module are described, including multiple new approaches to design for controlling attachment line contamination and transition. Finally, a modification to the NLF design algorithm that allows independent control of Tollmien-Schlichting (TS) and cross flow (CF) modes is proposed. A preliminary evaluation of the TS-only option applied to the design of an NLF nacelle for the CRM is performed that includes the use of a low-fidelity stability analysis directly in the design module.

Radiation protective structure alternatives for habitats of a lunar base research outpost

NASA Technical Reports Server (NTRS)

Bell, Fred J.; Foo, Lai T.; Mcgrew, William P.

1988-01-01

The solar and galactic cosmic radiation levels on the Moon pose a hazard to extended manned lunar missions. Lunar soil represents an available, economical material to be used for radiation shielding. Several alternatives have been suggested to use lunar soil to protect the inhabitants of a lunar base research outpost from radiation. The Universities Space Research Association has requested that a comparative analysis of the alternatives be performed, with the purpose of developing the most advantageous design. Eight alternatives have been analyzed, including an original design which was developed to satisfy the identified design criteria. The original design consists of a cylindrical module and airlock, partially buried in the lunar soil, at a depth sufficient to achieve adequate radiation shielding. The report includes descriptions of the alternatives considered, the method of analysis used, and the final design selected.

Design, fabrication, test, qualification and price analysis of third generation design solar cell modules. Part 1: Intermediate load module

NASA Technical Reports Server (NTRS)

Bottenberg, W. R.

1981-01-01

The updated program plan and narrative reflects the design and development work done and progress made in establishing a viable design for these modules. Design alterations from the preproduction plan are discussed based on experience gained during the preproduction phase of the program.

Task Design for Students' Work with Basic Theory in Analysis: The Cases of Multidimensional Differentiability and Curve Integrals

ERIC Educational Resources Information Center

Gravesen, Katrine Frovin; Grønbaek, Niels; Winsløw, Carl

2017-01-01

We investigate the challenges students face in the transition from calculus courses, focusing on methods related to the analysis of real valued functions given in closed form, to more advanced courses on analysis where focus is on theoretical structure, including proof. We do so based on task design aiming for a number of generic potentials for…

Side-polished fiber based gain-flattening filter for erbium doped fiber amplifiers

NASA Astrophysics Data System (ADS)

Varshney, R. K.; Singh, A.; Pande, K.; Pal, B. P.

2007-03-01

A simple and accurate novel normal mode analysis has been developed to take into account the effect of the non-uniform depth of polishing in the study of the transmission characteristics of optical waveguide devices based on loading of a side-polished fiber half-coupler with a multimode planar waveguide. We apply the same to design and fabricate a gain-flattening filter suitable for fiber amplifiers. The wavelength dependent filtering action of the overall device could demonstrate flattening of an EDFA gain spectrum within ±0.7 dB over a bandwidth of 30 nm in the C-band. Results obtained by the present analysis agree very well with our experimental results. This present analysis should be very useful in the accurate design and analysis of any SPF-MMOW device/component including side-polished fiber based sensors.

A Conceptual Wing Flutter Analysis Tool for Systems Analysis and Parametric Design Study

NASA Technical Reports Server (NTRS)

Mukhopadhyay, Vivek

2003-01-01

An interactive computer program was developed for wing flutter analysis in the conceptual design stage. The objective was to estimate flutt er instability boundaries of a typical wing, when detailed structural and aerodynamic data are not available. Effects of change in key flu tter parameters can also be estimated in order to guide the conceptual design. This userfriendly software was developed using MathCad and M atlab codes. The analysis method was based on non-dimensional paramet ric plots of two primary flutter parameters, namely Regier number and Flutter number, with normalization factors based on wing torsion stiffness, sweep, mass ratio, taper ratio, aspect ratio, center of gravit y location and pitch-inertia radius of gyration. These parametric plo ts were compiled in a Chance-Vought Corporation report from database of past experiments and wind tunnel test results. An example was prese nted for conceptual flutter analysis of outer-wing of a Blended-Wing- Body aircraft.

Maximum unbiased validation (MUV) data sets for virtual screening based on PubChem bioactivity data.

PubMed

Rohrer, Sebastian G; Baumann, Knut

2009-02-01

Refined nearest neighbor analysis was recently introduced for the analysis of virtual screening benchmark data sets. It constitutes a technique from the field of spatial statistics and provides a mathematical framework for the nonparametric analysis of mapped point patterns. Here, refined nearest neighbor analysis is used to design benchmark data sets for virtual screening based on PubChem bioactivity data. A workflow is devised that purges data sets of compounds active against pharmaceutically relevant targets from unselective hits. Topological optimization using experimental design strategies monitored by refined nearest neighbor analysis functions is applied to generate corresponding data sets of actives and decoys that are unbiased with regard to analogue bias and artificial enrichment. These data sets provide a tool for Maximum Unbiased Validation (MUV) of virtual screening methods. The data sets and a software package implementing the MUV design workflow are freely available at http://www.pharmchem.tu-bs.de/lehre/baumann/MUV.html.

Analysis and design of high-power and efficient, millimeter-wave power amplifier systems using zero degree combiners

NASA Astrophysics Data System (ADS)

Tai, Wei; Abbasi, Mortez; Ricketts, David S.

2018-01-01

We present the analysis and design of high-power millimetre-wave power amplifier (PA) systems using zero-degree combiners (ZDCs). The methodology presented optimises the PA device sizing and the number of combined unit PAs based on device load pull simulations, driver power consumption analysis and loss analysis of the ZDC. Our analysis shows that an optimal number of N-way combined unit PAs leads to the highest power-added efficiency (PAE) for a given output power. To illustrate our design methodology, we designed a 1-W PA system at 45 GHz using a 45 nm silicon-on-insulator process and showed that an 8-way combined PA has the highest PAE that yields simulated output power of 30.6 dBm and 31% peak PAE.

Design and performance analysis of gas and liquid radial turbines

NASA Astrophysics Data System (ADS)

Tan, Xu

In the first part of the research, pumps running in reverse as turbines are studied. This work uses experimental data of wide range of pumps representing the centrifugal pumps' configurations in terms of specific speed. Based on specific speed and specific diameter an accurate correlation is developed to predict the performances at best efficiency point of the centrifugal pump in its turbine mode operation. The proposed prediction method yields very good results to date compared to previous such attempts. The present method is compared to nine previous methods found in the literature. The comparison results show that the method proposed in this paper is the most accurate. The proposed method can be further complemented and supplemented by more future tests to increase its accuracy. The proposed method is meaningful because it is based both specific speed and specific diameter. The second part of the research is focused on the design and analysis of the radial gas turbine. The specification of the turbine is obtained from the solar biogas hybrid system. The system is theoretically analyzed and constructed based on the purchased compressor. Theoretical analysis results in a specification of 100lb/min, 900ºC inlet total temperature and 1.575atm inlet total pressure. 1-D and 3-D geometry of the rotor is generated based on Aungier's method. 1-D loss model analysis and 3-D CFD simulations are performed to examine the performances of the rotor. The total-to-total efficiency of the rotor is more than 90%. With the help of CFD analysis, modifications on the preliminary design obtained optimized aerodynamic performances. At last, the theoretical performance analysis on the hybrid system is performed with the designed turbine.

A non-stationary cost-benefit based bivariate extreme flood estimation approach

NASA Astrophysics Data System (ADS)

Qi, Wei; Liu, Junguo

2018-02-01

Cost-benefit analysis and flood frequency analysis have been integrated into a comprehensive framework to estimate cost effective design values. However, previous cost-benefit based extreme flood estimation is based on stationary assumptions and analyze dependent flood variables separately. A Non-Stationary Cost-Benefit based bivariate design flood estimation (NSCOBE) approach is developed in this study to investigate influence of non-stationarities in both the dependence of flood variables and the marginal distributions on extreme flood estimation. The dependence is modeled utilizing copula functions. Previous design flood selection criteria are not suitable for NSCOBE since they ignore time changing dependence of flood variables. Therefore, a risk calculation approach is proposed based on non-stationarities in both marginal probability distributions and copula functions. A case study with 54-year observed data is utilized to illustrate the application of NSCOBE. Results show NSCOBE can effectively integrate non-stationarities in both copula functions and marginal distributions into cost-benefit based design flood estimation. It is also found that there is a trade-off between maximum probability of exceedance calculated from copula functions and marginal distributions. This study for the first time provides a new approach towards a better understanding of influence of non-stationarities in both copula functions and marginal distributions on extreme flood estimation, and could be beneficial to cost-benefit based non-stationary bivariate design flood estimation across the world.

Molecular design of anticancer drug leads based on three-dimensional quantitative structure-activity relationship.

PubMed

Huang, Xiao Yan; Shan, Zhi Jie; Zhai, Hong Lin; Li, Li Na; Zhang, Xiao Yun

2011-08-22

Heat shock protein 90 (Hsp90) takes part in the developments of several cancers. Novobiocin, a typically C-terminal inhibitor for Hsp90, will probably used as an important anticancer drug in the future. In this work, we explored the valuable information and designed new novobiocin derivatives based on a three-dimensional quantitative structure-activity relationship (3D QSAR). The comparative molecular field analysis and comparative molecular similarity indices analysis models with high predictive capability were established, and their reliabilities are supported by the statistical parameters. Based on the several important influence factors obtained from these models, six new novobiocin derivatives with higher inhibitory activities were designed and confirmed by the molecular simulation with our models, which provide the potential anticancer drug leads for further research.

Karyotype Analysis Activity: A Constructivist Learning Design

ERIC Educational Resources Information Center

Ahmed, Noveera T.

2015-01-01

This classroom activity is based on a constructivist learning design and engages students in physically constructing a karyotype of three mock patients. Students then diagnose the chromosomal aneuploidy based on the karyotype, list the symptoms associated with the disorder, and discuss the implications of the diagnosis. This activity is targeted…

A Library Based Apprenticeship in Psychology Research.

ERIC Educational Resources Information Center

Ross, Linda; Carter, Elizabeth W.

A collaboration to develop materials that will foster critical thinking and communication skills through library-based research is described and presented. Library activities were designed to promote the use of cognitive skills, such as analysis, synthesis, and evaluation. This was a pilot study designed to expose undergraduate students to one…

Search Interface Design Using Faceted Indexing for Web Resources.

ERIC Educational Resources Information Center

Devadason, Francis; Intaraksa, Neelawat; Patamawongjariya, Pornprapa; Desai, Kavita

2001-01-01

Describes an experimental system designed to organize and provide access to Web documents using a faceted pre-coordinate indexing system based on the Deep Structure Indexing System (DSIS) derived from POPSI (Postulate based Permuted Subject Indexing) of Bhattacharyya, and the facet analysis and chain indexing system of Ranganathan. (AEF)

Proposing a New Pedagogy-Based Website Design: A Usability Test with Lifelong Learners

ERIC Educational Resources Information Center

Khlaisang, Jintavee

2017-01-01

This study aimed to create a new pedagogy-based website based on the analysis of the needs of 7147 website users who visited the Thailand Cyber University (TCU) project website during 2011-2013. The study consisted of 4 stages: (1) examining learners' needs and literature related to developing a lifelong learning framework, (2) designing a site…

Air Force Nuclear Enterprise Organization: A Case Study

DTIC Science & Technology

2016-09-15

will improve the performance of the AFNE. Based on analysis of commercial and industrial business models, what organizational structure , or...Business Dictionary 2015). Organizational structures will be developed based on decisions made with regards to design. The core of an...work flows. Based on design parameter decisions, senior leaders will establish an organizational structure that includes the layout of the

Hardware accelerated high performance neutron transport computation based on AGENT methodology

NASA Astrophysics Data System (ADS)

Xiao, Shanjie

The spatial heterogeneity of the next generation Gen-IV nuclear reactor core designs brings challenges to the neutron transport analysis. The Arbitrary Geometry Neutron Transport (AGENT) AGENT code is a three-dimensional neutron transport analysis code being developed at the Laboratory for Neutronics and Geometry Computation (NEGE) at Purdue University. It can accurately describe the spatial heterogeneity in a hierarchical structure through the R-function solid modeler. The previous version of AGENT coupled the 2D transport MOC solver and the 1D diffusion NEM solver to solve the three dimensional Boltzmann transport equation. In this research, the 2D/1D coupling methodology was expanded to couple two transport solvers, the radial 2D MOC solver and the axial 1D MOC solver, for better accuracy. The expansion was benchmarked with the widely applied C5G7 benchmark models and two fast breeder reactor models, and showed good agreement with the reference Monte Carlo results. In practice, the accurate neutron transport analysis for a full reactor core is still time-consuming and thus limits its application. Therefore, another content of my research is focused on designing a specific hardware based on the reconfigurable computing technique in order to accelerate AGENT computations. It is the first time that the application of this type is used to the reactor physics and neutron transport for reactor design. The most time consuming part of the AGENT algorithm was identified. Moreover, the architecture of the AGENT acceleration system was designed based on the analysis. Through the parallel computation on the specially designed, highly efficient architecture, the acceleration design on FPGA acquires high performance at the much lower working frequency than CPUs. The whole design simulations show that the acceleration design would be able to speedup large scale AGENT computations about 20 times. The high performance AGENT acceleration system will drastically shortening the computation time for 3D full-core neutron transport analysis, making the AGENT methodology unique and advantageous, and thus supplies the possibility to extend the application range of neutron transport analysis in either industry engineering or academic research.

A supportive architecture for CFD-based design optimisation

NASA Astrophysics Data System (ADS)

Li, Ni; Su, Zeya; Bi, Zhuming; Tian, Chao; Ren, Zhiming; Gong, Guanghong

2014-03-01

Multi-disciplinary design optimisation (MDO) is one of critical methodologies to the implementation of enterprise systems (ES). MDO requiring the analysis of fluid dynamics raises a special challenge due to its extremely intensive computation. The rapid development of computational fluid dynamic (CFD) technique has caused a rise of its applications in various fields. Especially for the exterior designs of vehicles, CFD has become one of the three main design tools comparable to analytical approaches and wind tunnel experiments. CFD-based design optimisation is an effective way to achieve the desired performance under the given constraints. However, due to the complexity of CFD, integrating with CFD analysis in an intelligent optimisation algorithm is not straightforward. It is a challenge to solve a CFD-based design problem, which is usually with high dimensions, and multiple objectives and constraints. It is desirable to have an integrated architecture for CFD-based design optimisation. However, our review on existing works has found that very few researchers have studied on the assistive tools to facilitate CFD-based design optimisation. In the paper, a multi-layer architecture and a general procedure are proposed to integrate different CFD toolsets with intelligent optimisation algorithms, parallel computing technique and other techniques for efficient computation. In the proposed architecture, the integration is performed either at the code level or data level to fully utilise the capabilities of different assistive tools. Two intelligent algorithms are developed and embedded with parallel computing. These algorithms, together with the supportive architecture, lay a solid foundation for various applications of CFD-based design optimisation. To illustrate the effectiveness of the proposed architecture and algorithms, the case studies on aerodynamic shape design of a hypersonic cruising vehicle are provided, and the result has shown that the proposed architecture and developed algorithms have performed successfully and efficiently in dealing with the design optimisation with over 200 design variables.

Progress in multirate digital control system design

NASA Technical Reports Server (NTRS)

Berg, Martin C.; Mason, Gregory S.

1991-01-01

A new methodology for multirate sampled-data control design based on a new generalized control law structure, two new parameter-optimization-based control law synthesis methods, and a new singular-value-based robustness analysis method are described. The control law structure can represent multirate sampled-data control laws of arbitrary structure and dynamic order, with arbitrarily prescribed sampling rates for all sensors and update rates for all processor states and actuators. The two control law synthesis methods employ numerical optimization to determine values for the control law parameters. The robustness analysis method is based on the multivariable Nyquist criterion applied to the loop transfer function for the sampling period equal to the period of repetition of the system's complete sampling/update schedule. The complete methodology is demonstrated by application to the design of a combination yaw damper and modal suppression system for a commercial aircraft.

Relativity effects for space-based coherent lidar experiments

NASA Technical Reports Server (NTRS)

Gudimetla, V. S. Rao

1996-01-01

An effort was initiated last year in the Astrionics Laboratory at Marshall Space Flight Center to examine and incorporate, if necessary, the effects of relativity in the design of space-based lidar systems. A space-based lidar system, named AEOLUS, is under development at Marshall Space Flight Center and it will be used to accurately measure atmospheric wind profiles. Effects of relativity were also observed in the performance of space-based systems, for example in case of global positioning systems, and corrections were incorporated into the design of instruments. During the last summer, the effects of special relativity on the design of space-based lidar systems were studied in detail, by analyzing the problem of laser scattering off a fixed target when the source and a co-located receiver are moving on a spacecraft. Since the proposed lidar system uses a coherent detection system, errors even in the order of a few microradians must be corrected to achieve a good signal-to-noise ratio. Previous analysis assumed that the ground is flat and the spacecraft is moving parallel to the ground, and developed analytical expressions for the location, direction and Doppler shift of the returning radiation. Because of the assumptions used in that analysis, only special relativity effects were involved. In this report, that analysis is extended to include general relativity and calculate its effects on the design.

Exergy Analysis of Rocket Systems

NASA Technical Reports Server (NTRS)

Gilbert, Andrew; Mesmer, Bryan; Watson, Michael D.

2015-01-01

Exergy is defined as the useful work available from a system in a specified environment. Exergy analysis allows for comparison between different system designs, and allows for comparison of subsystem efficiencies within system designs. The proposed paper explores the relationship between the fundamental rocket equation and an exergy balance equation. A previously derived exergy equation related to rocket systems is investigated, and a higher fidelity analysis will be derived. The exergy assessments will enable informed, value-based decision making when comparing alternative rocket system designs, and will allow the most efficient configuration among candidate configurations to be determined.

Geometry and Function Definition for Discrete Analysis and Its Relationship to the Design Data Base.

DTIC Science & Technology

1977-08-01

clarif y its dependenc e on the design process as a whole . The model generation capabilities of a state—of—the—art structural analysis system ( GIFTS ...a whole. The model generat ion capabilit ies of a state—of—the—art structural analysis system ( GIFTS 4), heav ily oriented toward s pre— and post...independentl y at a later stage. Ii . 1,1 ~1E TP IC HIER.ARCHY ~)F DEFINITION IN GIFTS ‘+ A three-d imensional object , to be designed or analyz ed

Role of IAC in large space systems thermal analysis

NASA Technical Reports Server (NTRS)

Jones, G. K.; Skladany, J. T.; Young, J. P.

1982-01-01

Computer analysis programs to evaluate critical coupling effects that can significantly influence spacecraft system performance are described. These coupling effects arise from the varied parameters of the spacecraft systems, environments, and forcing functions associated with disciplines such as thermal, structures, and controls. Adverse effects can be expected to significantly impact system design aspects such as structural integrity, controllability, and mission performance. One such needed design analysis capability is a software system that can integrate individual discipline computer codes into a highly user-oriented/interactive-graphics-based analysis capability. The integrated analysis capability (IAC) system can be viewed as: a core framework system which serves as an integrating base whereby users can readily add desired analysis modules and as a self-contained interdisciplinary system analysis capability having a specific set of fully integrated multidisciplinary analysis programs that deal with the coupling of thermal, structures, controls, antenna radiation performance, and instrument optical performance disciplines.

A multiobjective decision support/numerical modeling approach for design and evaluation of shallow landfill burial systems

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

Ascough, II, James Clifford

1992-05-01

The capability to objectively evaluate design performance of shallow landfill burial (SLB) systems is of great interest to diverse scientific disciplines, including hydrologists, engineers, environmental scientists, and SLB regulators. The goal of this work was to develop and validate a procedure for the nonsubjective evaluation of SLB designs under actual or simulated environmental conditions. A multiobjective decision module (MDM) based on scoring functions (Wymore, 1988) was implemented to evaluate SLB design performance. Input values to the MDM are provided by hydrologic models. The MDM assigns a total score to each SLB design alternative, thereby allowing for rapid and repeatable designmore » performance evaluation. The MDM was validated for a wide range of SLB designs under different climatic conditions. Rigorous assessment of SLB performance also requires incorporation of hydrologic probabilistic analysis and hydrologic risk into the overall design. This was accomplished through the development of a frequency analysis module. The frequency analysis module allows SLB design event magnitudes to be calculated based on the hydrologic return period. The multiobjective decision and freqeuncy anslysis modules were integrated in a decision support system (DSS) framework, SLEUTH (Shallow Landfill Evaluation Using Transport and Hydrology). SLEUTH is a Microsoft Windows {trademark} application, and is written in the Knowledge Pro Windows (Knowledge Garden, Inc., 1991) development language.« less

Design optimization of hydraulic turbine draft tube based on CFD and DOE method

NASA Astrophysics Data System (ADS)

Nam, Mun chol; Dechun, Ba; Xiangji, Yue; Mingri, Jin

2018-03-01

In order to improve performance of the hydraulic turbine draft tube in its design process, the optimization for draft tube is performed based on multi-disciplinary collaborative design optimization platform by combining the computation fluid dynamic (CFD) and the design of experiment (DOE) in this paper. The geometrical design variables are considered as the median section in the draft tube and the cross section in its exit diffuser and objective function is to maximize the pressure recovery factor (Cp). Sample matrixes required for the shape optimization of the draft tube are generated by optimal Latin hypercube (OLH) method of the DOE technique and their performances are evaluated through computational fluid dynamic (CFD) numerical simulation. Subsequently the main effect analysis and the sensitivity analysis of the geometrical parameters of the draft tube are accomplished. Then, the design optimization of the geometrical design variables is determined using the response surface method. The optimization result of the draft tube shows a marked performance improvement over the original.

Design and analysis of MEMS MWCNT/epoxy strain sensor using COMSOL

NASA Astrophysics Data System (ADS)

Sapra, Gaurav; Sharma, Preetika

2017-07-01

The design and performance of piezoresistive MEMS-based MWCNT/epoxy composite strain sensor using COMSOL Multiphysics Toolbox has been investigated. The proposed sensor design comprises su-8 based U-shaped cantilever beam with MWCNT/epoxy composite film as an active sensing element. A point load in microscale has been applied at the tip of the cantilever beam to observe its deflection in the proposed design. Analytical simulations have been performed to optimize various design parameters of the proposed sensor, which will be helpful at the time of fabrication.

Language Analysis Package (L.A.P.) Version I System Design.

ERIC Educational Resources Information Center

Porch, Ann

To permit researchers to use the speed and versatility of the computer to process natural language text as well as numerical data without undergoing special training in programing or computer operations, a language analysis package has been developed partially based on several existing programs. An overview of the design is provided and system…

QoS Composition and Decomposition Model in Uniframe

DTIC Science & Technology

2003-08-01

Architecture Tradeoff Analysis Method.………………….19 2.2 Analysis of Non-Functional Requirements at the Early Design Phase………19 2.2.1 Parmenides Framework...early design phase are discussed in the following sections. 2.2.1 Parmenides Framework In [22], an architecture-based framework is proposed for

The Brazilian Experience with Agroecological Extension: A Critical Analysis of Reform in a Pluralistic Extension System

ERIC Educational Resources Information Center

Diesel, Vivien; Miná Dias, Marcelo

2016-01-01

Purpose: To analyze the Brazilian experience in designing and implementing a recent extension policy reform based on agroecology, and reflect on its wider theoretical implications for extension reform literature. Design/methodology/approach: Using a critical public analysis we characterize the evolution of Brazilian federal extension policy…

Surface Modeling, Solid Modeling and Finite Element Modeling. Analysis Capabilities of Computer-Assisted Design and Manufacturing Systems.

ERIC Educational Resources Information Center

Nee, John G.; Kare, Audhut P.

1987-01-01

Explores several concepts in computer assisted design/computer assisted manufacturing (CAD/CAM). Defines, evaluates, reviews and compares advanced computer-aided geometric modeling and analysis techniques. Presents the results of a survey to establish the capabilities of minicomputer based-systems with the CAD/CAM packages evaluated. (CW)

10 CFR 72.240 - Conditions for spent fuel storage cask renewal.

Code of Federal Regulations, 2013 CFR

2013-01-01

... to exceed 40 years. In the event that the certificate holder does not apply for a cask design renewal...) The application must be accompanied by a safety analysis report (SAR). The SAR must include the following: (1) Design bases information as documented in the most recently updated final safety analysis...

10 CFR 72.240 - Conditions for spent fuel storage cask renewal.

Code of Federal Regulations, 2012 CFR

2012-01-01

... to exceed 40 years. In the event that the certificate holder does not apply for a cask design renewal...) The application must be accompanied by a safety analysis report (SAR). The SAR must include the following: (1) Design bases information as documented in the most recently updated final safety analysis...

10 CFR 72.240 - Conditions for spent fuel storage cask renewal.

Code of Federal Regulations, 2014 CFR

2014-01-01

... to exceed 40 years. In the event that the certificate holder does not apply for a cask design renewal...) The application must be accompanied by a safety analysis report (SAR). The SAR must include the following: (1) Design bases information as documented in the most recently updated final safety analysis...

The NASA/industry design analysis methods for vibrations (DAMVIBS) program - Accomplishments and contributions

NASA Technical Reports Server (NTRS)

Kvaternik, Raymond G.

1991-01-01

A NASA Langley-sponsored rotorcraft structural dynamics program, known as Design Analysis Methods for VIBrationS (DAMVIBS), has been under development since 1984. The objective of this program was to establish the technology base needed by the industry to develop an advanced finite-element-based dynamics design analysis capability for vibrations. Under the program, teams from the four major helicopter manufacturers have formed finite-element models, conducted ground vibration tests, made test/analysis comparisons of both metal and composite airframes, performed 'difficult components' studies on airframes to identify components which need more complete finite-element representation for improved correlation, and evaluated industry codes for computing coupled rotor-airframe vibrations. Studies aimed at establishing the role that structural optimization can play in airframe vibrations design work have also been initiated. Five government/industry meetings were held in connection with these activities during the course of the program. Because the DAMVIBS Program is coming to an end, the fifth meeting included a brief assessment of the program and its benefits to the industry.

The NASA/industry design analysis methods for vibrations (DAMVIBS) program: Accomplishments and contributions

NASA Technical Reports Server (NTRS)

Kvaternik, Raymond G.

1991-01-01

A NASA Langley-sponsored rotorcraft structural dynamics program, known as Design Analysis Methods for VIBrationS (DAMVIBS), has been under development since 1984. The objective of this program was to establish the technology base needed by the industry to develop an advanced finite-element-based dynamics design analysis capability for vibrations. Under the program, teams from the four major helicopter manufacturers have formed finite-element models, conducted ground vibration tests, made test/analysis comparisons of both metal and composite airframes, performed 'difficult components' studies on airframes to identify components which need more complete finite-element representation for improved correlation, and evaluated industry codes for computing coupled rotor-airframe vibrations. Studies aimed at establishing the role that structural optimization can play in airframe vibrations design work have also been initiated. Five government/industry meetings were held in connection with these activities during the course of the program. Because the DAMVIBS Program is coming to an end, the fifth meeting included a brief assessment of the program and its benefits to the industry.

Strength Analysis on Ship Ladder Using Finite Element Method

NASA Astrophysics Data System (ADS)

Budianto; Wahyudi, M. T.; Dinata, U.; Ruddianto; Eko P., M. M.

2018-01-01

In designing the ship’s structure, it should refer to the rules in accordance with applicable classification standards. In this case, designing Ladder (Staircase) on a Ferry Ship which is set up, it must be reviewed based on the loads during ship operations, either during sailing or at port operations. The classification rules in ship design refer to the calculation of the structure components described in Classification calculation method and can be analysed using the Finite Element Method. Classification Regulations used in the design of Ferry Ships used BKI (Bureau of Classification Indonesia). So the rules for the provision of material composition in the mechanical properties of the material should refer to the classification of the used vessel. The analysis in this structure used program structure packages based on Finite Element Method. By using structural analysis on Ladder (Ladder), it obtained strength and simulation structure that can withstand load 140 kg both in static condition, dynamic, and impact. Therefore, the result of the analysis included values of safety factors in the ship is to keep the structure safe but the strength of the structure is not excessive.

Study on comparison of special moment frame steel structure (SMF) and base isolation special moment frame steel structure (BI-SMF) in Indonesia

NASA Astrophysics Data System (ADS)

Setiawan, Jody; Nakazawa, Shoji

2017-10-01

This paper discusses about comparison of seismic response behaviors, seismic performance and seismic loss function of a conventional special moment frame steel structure (SMF) and a special moment frame steel structure with base isolation (BI-SMF). The validation of the proposed simplified estimation method of the maximum deformation of the base isolation system by using the equivalent linearization method and the validation of the design shear force of the superstructure are investigated from results of the nonlinear dynamic response analysis. In recent years, the constructions of steel office buildings with seismic isolation system are proceeding even in Indonesia where the risk of earthquakes is high. Although the design code for the seismic isolation structure has been proposed, there is no actual construction example for special moment frame steel structure with base isolation. Therefore, in this research, the SMF and BI-SMF buildings are designed by Indonesian Building Code which are assumed to be built at Padang City in Indonesia. The material of base isolation system is high damping rubber bearing. Dynamic eigenvalue analysis and nonlinear dynamic response analysis are carried out to show the dynamic characteristics and seismic performance. In addition, the seismic loss function is obtained from damage state probability and repair cost. For the response analysis, simulated ground accelerations, which have the phases of recorded seismic waves (El Centro NS, El Centro EW, Kobe NS and Kobe EW), adapted to the response spectrum prescribed by the Indonesian design code, that has, are used.

Approximate simulation model for analysis and optimization in engineering system design

NASA Technical Reports Server (NTRS)

Sobieszczanski-Sobieski, Jaroslaw

1989-01-01

Computational support of the engineering design process routinely requires mathematical models of behavior to inform designers of the system response to external stimuli. However, designers also need to know the effect of the changes in design variable values on the system behavior. For large engineering systems, the conventional way of evaluating these effects by repetitive simulation of behavior for perturbed variables is impractical because of excessive cost and inadequate accuracy. An alternative is described based on recently developed system sensitivity analysis that is combined with extrapolation to form a model of design. This design model is complementary to the model of behavior and capable of direct simulation of the effects of design variable changes.

Finite element prediction on the chassis design of UniART4 racing car

NASA Astrophysics Data System (ADS)

Zaman, Z. I.; Basaruddin, K. S.; Basha, M. H.; Rahman, M. T. Abd; Daud, R.

2017-09-01

This paper presents the analysis and evaluation of the chassis design for University Automotive Racing Team No. 4 (UniART4) car based on finite element analysis. The existing UniART4 car chassis was measured and modelled geometrically using Solidwork before analysed in FEA software (ANSYS). Four types of static structural analysis were used to predict the chassis design capability under four different loading conditions; vertical bending, lateral bending, lateral torsion and horizontal lozenging. The results showed the chassis subjected to the highest stress and strain under horizontal lozenging, whereas the minimum stress and strain response was obtained under lateral bending. The present analysis result could provide valuable information in predicting the sustainability of the current UniART car chassis design.

User Interface Requirements for Web-Based Integrated Care Pathways: Evidence from the Evaluation of an Online Care Pathway Investigation Tool.

PubMed

Balatsoukas, Panos; Williams, Richard; Davies, Colin; Ainsworth, John; Buchan, Iain

2015-11-01

Integrated care pathways (ICPs) define a chronological sequence of steps, most commonly diagnostic or treatment, to be followed in providing care for patients. Care pathways help to ensure quality standards are met and to reduce variation in practice. Although research on the computerisation of ICP progresses, there is still little knowledge on what are the requirements for designing user-friendly and usable electronic care pathways, or how users (normally health care professionals) interact with interfaces that support design, analysis and visualisation of ICPs. The purpose of the study reported in this paper was to address this gap by evaluating the usability of a novel web-based tool called COCPIT (Collaborative Online Care Pathway Investigation Tool). COCPIT supports the design, analysis and visualisation of ICPs at the population level. In order to address the aim of this study, an evaluation methodology was designed based on heuristic evaluations and a mixed method usability test. The results showed that modular visualisation and direct manipulation of information related to the design and analysis of ICPs is useful for engaging and stimulating users. However, designers should pay attention to issues related to the visibility of the system status and the match between the system and the real world, especially in relation to the display of statistical information about care pathways and the editing of clinical information within a care pathway. The paper concludes with recommendations for interface design.

Design and analysis of coherent OCDM en/decoder based on photonic crystal

NASA Astrophysics Data System (ADS)

Zhang, Chongfu; Qiu, Kun

2008-08-01

The design and performance analysis of a new coherent optical en/decoder based on photonic crystal (PhC) for optical code -division -multiple (OCDM) are presented in this paper. In this scheme, the optical pulse phase and time delay can be flexibly controlled by photonic crystal phase shifter and time delayer by using the appropriate design of fabrication. According to the PhC transmission matrix theorem, combination calculation of the impurity and normal period layers is applied, and performances of the PhC-based optical en/decoder are also analyzed. The reflection, transmission, time delay characteristic and optical spectrum of pulse en/decoded are studied for the waves tuned in the photonic band-gap by numerical calculation. Theoretical analysis and numerical results indicate that the optical pulse is achieved to properly phase modulation and time delay, and an auto-correlation of about 8 dB ration and cross-correlation is gained, which demonstrates the applicability of true pulse phase modulation in a number of applications.

Managing Analysis Models in the Design Process

NASA Technical Reports Server (NTRS)

Briggs, Clark

2006-01-01

Design of large, complex space systems depends on significant model-based support for exploration of the design space. Integrated models predict system performance in mission-relevant terms given design descriptions and multiple physics-based numerical models. Both the design activities and the modeling activities warrant explicit process definitions and active process management to protect the project from excessive risk. Software and systems engineering processes have been formalized and similar formal process activities are under development for design engineering and integrated modeling. JPL is establishing a modeling process to define development and application of such system-level models.

Convoy Protection under Multi-Threat Scenario

DTIC Science & Technology

2017-06-01

14. SUBJECT TERMS antisubmarine warfare, convoy protection, screening, design of experiments, agent-based simulation 15. NUMBER OF...46 5. Scenarios 33–36 (Red Submarine Tactic-2) ...............................46 IV. DESIGN OF EXPERIMENT...47 C. NEARLY ORTHOGONAL LATIN HYPERCUBE DESIGN ............51 V. DATA ANALYSIS

General specifications for the development of a PC-based simulator of the NASA RECON system

NASA Technical Reports Server (NTRS)

Dominick, Wayne D. (Editor); Triantafyllopoulos, Spiros

1984-01-01

The general specifications for the design and implementation of an IBM PC/XT-based simulator of the NASA RECON system, including record designs, file structure designs, command language analysis, program design issues, error recovery considerations, and usage monitoring facilities are discussed. Once implemented, such a simulator will be utilized to evaluate the effectiveness of simulated information system access in addition to actual system usage as part of the total educational programs being developed within the NASA contract.

A Meta-Analysis Method to Advance Design of Technology-Based Learning Tool: Combining Qualitative and Quantitative Research to Understand Learning in Relation to Different Technology Features

ERIC Educational Resources Information Center

Zhang, Lin

2014-01-01

Educators design and create various technology tools to scaffold students' learning. As more and more technology designs are incorporated into learning, growing attention has been paid to the study of technology-based learning tool. This paper discusses the emerging issues, such as how can learning effectiveness be understood in relation to…

School-Based Peer-Related Social Competence Interventions for Children with Autism Spectrum Disorder: A Meta-Analysis and Descriptive Review of Single Case Research Design Studies

ERIC Educational Resources Information Center

Whalon, Kelly J.; Conroy, Maureen A.; Martinez, Jose R.; Werch, Brittany L.

2015-01-01

The purpose of this review was to critically examine and summarize the impact of school-based interventions designed to facilitate the peer-related social competence of children with autism spectrum disorder (ASD). Reviewed studies employed a single-case experimental design, targeted peer-related social competence, included children 3-12 years old…

Assessing Consequential Scenarios in a Complex Operational Environment Using Agent Based Simulation

DTIC Science & Technology

2017-03-16

RWISE) 93 5.1.5 Conflict Modeling, Planning, and Outcomes Experimentation Program (COMPOEX) 94 5.1.6 Joint Non -Kinetic Effects Model (JNEM)/Athena... experimental design and testing. 4.3.8 Types and Attributes of Agent-Based Model Design Patterns Using the aforementioned ABM flowchart design methodology ...speed, or flexibility during tactical US Army wargaming. The report considers methodologies to improve analysis of the human domain, identifies

Proceedings of Selected Research and Development Presentations at the National Convention of the Association for Educational Communications and Technology (AECT) Sponsored by the Research and Theory Division (20th, St. Louis, Missouri, February 18-22, 1998).

ERIC Educational Resources Information Center

Maushak, Nancy J., Ed.; Schlosser, Charles, Ed.; Lloyd, Thomas N., Ed.; Simonson, Michael, Ed.

1998-01-01

Subjects addressed by the 55 papers in this proceedings include: teaching literacy; hypermedia navigation and design; creating a community of thinkers; analysis-based message design; learner-instruction interactions; representation of time-based information in visual design; presentation interference; professional development through anecdotes;…

Role of Theories in the Design of Web-Based Person-Centered Support: A Critical Analysis

PubMed Central

Ranerup, Agneta; Sparud-Lundin, Carina; Koinberg, Ingalill; Skärsäter, Ingela; Jenholt-Nolbris, Margaretha; Berg, Marie

2014-01-01

Objective. The aim of this study was to provide a critical understanding of the role of theories and their compatibility with a person-centered approach in the design and evaluation of web-based support for the management of chronic illness. Methods. Exploration of web-based support research projects focusing on four cases: (1) preschool children aged 4–6 with bladder dysfunction and urogenital malformation; (2) young adults aged 16–25 living with mental illness; (3) women with type 1 diabetes who are pregnant or in early motherhood; and (4) women who have undergone surgery for breast cancer. Data comprised interviews with research leaders and documented plans. Analysis was performed by means of a cross-case methodology. Results. The used theories concerned design, learning, health and well-being, or transition. All web support products had been developed using a participatory design (PD). Fundamental to the technology design and evaluation of outcomes were theories focusing on learning and on health and well-being. All theories were compatible with a person-centered approach. However, a notable exception was the relatively collective character of PD and Communities of Practice. Conclusion. Our results illustrate multifaceted ways for theories to be used in the design and evaluation of web-based support. PMID:26464860

[Development of a portable ambulatory ECG monitor based on embedded microprocessor unit].

PubMed

Wang, Da-xiong; Wang, Guo-jun

2005-06-01

To develop a new kind of portable ambulatory ECG monitor. The hardware and software were designed based on RCA-CDP1802. New methods of ECG data compression and feature extraction of QRS complexes were applied to software design. A model for automatic arrhythmia analysis was established for real-time ambulatory ECG Data analysis. Compact, low power consumption and low cost were emphasized in the hardware design. This compact and light-weight monitor with low power consumption and high intelligence was capable of real-time monitoring arrhythmia for more than 48 h. More than ten types of arrhythmia could be detected, only the compressed abnormal ECG data was recorded and could be transmitted to the host if required. The monitor meets the design requirements and can be used for ambulatory ECG monitoring.

Design Process Improvement for Electric CAR Harness

NASA Astrophysics Data System (ADS)

Sawatdee, Thiwarat; Chutima, Parames

2017-06-01

In an automobile parts design company, the customer satisfaction is one of the most important factors for product design. Therefore, the company employs all means to focus its product design process based on the various requirements of customers resulting in high number of design changes. The objective of this research is to improve the design process of the electric car harness that effects the production scheduling by using Fault Tree Analysis (FTA) and Failure Mode and Effect Analysis (FMEA) as the main tools. FTA is employed for root cause analysis and FMEA is used to ranking a High Risk Priority Number (RPN) which is shows the priority of factors in the electric car harness that have high impact to the design of the electric car harness. After the implementation, the improvements are realized significantly since the number of design change is reduced from 0.26% to 0.08%.

An inverse method for the aerodynamic design of three-dimensional aircraft engine nacelles

NASA Technical Reports Server (NTRS)

Bell, R. A.; Cedar, R. D.

1991-01-01

A fast, efficient and user friendly inverse design system for 3-D nacelles was developed. The system is a product of a 2-D inverse design method originally developed at NASA-Langley and the CFL3D analysis code which was also developed at NASA-Langley and modified for nacelle analysis. The design system uses a predictor/corrector design approach in which an analysis code is used to calculate the flow field for an initial geometry, the geometry is then modified based on the difference between the calculated and target pressures. A detailed discussion of the design method, the process of linking it to the modified CFL3D solver and its extension to 3-D is presented. This is followed by a number of examples of the use of the design system for the design of both axisymmetric and 3-D nacelles.

Sensitivity analysis of navy aviation readiness based sparing model

DTIC Science & Technology

2017-09-01

variability. (See Figure 4.) Figure 4. Research design flowchart 18 Figure 4 lays out the four steps of the methodology , starting in the upper left-hand...as a function of changes in key inputs. We develop NAVARM Experimental Designs (NED), a computational tool created by applying a state-of-the-art...experimental design to the NAVARM model. Statistical analysis of the resulting data identifies the most influential cost factors. Those are, in order of

Metrics for Analyzing Quantifiable Differentiation of Designs with Varying Integrity for Hardware Assurance

DTIC Science & Technology

2017-03-01

proposed. Expected profiles can incorporate a level of overdesign. Finally, the Design Integrity measuring techniques are applied to five Test Article ...Inserted into Test System Table 2 presents the results of the analysis applied to each of the test article designs. Each of the domains are...the lowest integrities. Based on the analysis, the DI metric shows measurable differentiation between all five Test Article Error Location Error

Space Transportation System Payloads Data and Analysis

NASA Technical Reports Server (NTRS)

Peterson, J. D.; Craft, H. G., Jr.

1975-01-01

The background, current developments and future plans for the Space Transportation System Payloads Data and Analysis (SPDA) activities at Marshall Space Flight Center are reviewed. It is shown how the payload data bank and future planned activities will interface with the payloads community and Space Transportation System designers. The interfaces with the STS data base include NASA planning, international planning, payload design, shuttle design, user agencies planning and information, and OMB, Congress and others.

Wind Turbine Control Design to Reduce Capital Costs: 7 January 2009 - 31 August 2009

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

Darrow, P. J.

2010-01-01

This report first discusses and identifies which wind turbine components can benefit from advanced control algorithms and also presents results from a preliminary loads case analysis using a baseline controller. Next, it describes the design, implementation, and simulation-based testing of an advanced controller to reduce loads on those components. The case-by-case loads analysis and advanced controller design will help guide future control research.

The Health Services Mobility Study Method of Task Analysis and Curriculum Design. Research Report No. 11. Volume 3: Using the Computer to Develop Job Ladders.

ERIC Educational Resources Information Center

Gilpatrick, Eleanor

This document is volume 3 of a four-volume report which describes the components of the Health Services Mobility Study (HSMS) method of task analysis, job ladder design, and curriculum development. Divided into four chapters, volume 3 is a manual for using HSMS computer based statistical procedures to design job structures and job ladders. Chapter…

Self-reconfigurable ship fluid-network modeling for simulation-based design

NASA Astrophysics Data System (ADS)

Moon, Kyungjin

Our world is filled with large-scale engineering systems, which provide various services and conveniences in our daily life. A distinctive trend in the development of today's large-scale engineering systems is the extensive and aggressive adoption of automation and autonomy that enable the significant improvement of systems' robustness, efficiency, and performance, with considerably reduced manning and maintenance costs, and the U.S. Navy's DD(X), the next-generation destroyer program, is considered as an extreme example of such a trend. This thesis pursues a modeling solution for performing simulation-based analysis in the conceptual or preliminary design stage of an intelligent, self-reconfigurable ship fluid system, which is one of the concepts of DD(X) engineering plant development. Through the investigations on the Navy's approach for designing a more survivable ship system, it is found that the current naval simulation-based analysis environment is limited by the capability gaps in damage modeling, dynamic model reconfiguration, and simulation speed of the domain specific models, especially fluid network models. As enablers of filling these gaps, two essential elements were identified in the formulation of the modeling method. The first one is the graph-based topological modeling method, which will be employed for rapid model reconstruction and damage modeling, and the second one is the recurrent neural network-based, component-level surrogate modeling method, which will be used to improve the affordability and efficiency of the modeling and simulation (M&S) computations. The integration of the two methods can deliver computationally efficient, flexible, and automation-friendly M&S which will create an environment for more rigorous damage analysis and exploration of design alternatives. As a demonstration for evaluating the developed method, a simulation model of a notional ship fluid system was created, and a damage analysis was performed. Next, the models representing different design configurations of the fluid system were created, and damage analyses were performed with them in order to find an optimal design configuration for system survivability. Finally, the benefits and drawbacks of the developed method were discussed based on the result of the demonstration.

Multidisciplinary design optimization of vehicle instrument panel based on multi-objective genetic algorithm

NASA Astrophysics Data System (ADS)

Wang, Ping; Wu, Guangqiang

2013-03-01

Typical multidisciplinary design optimization(MDO) has gradually been proposed to balance performances of lightweight, noise, vibration and harshness(NVH) and safety for instrument panel(IP) structure in the automotive development. Nevertheless, plastic constitutive relation of Polypropylene(PP) under different strain rates, has not been taken into consideration in current reliability-based and collaborative IP MDO design. In this paper, based on tensile test under different strain rates, the constitutive relation of Polypropylene material is studied. Impact simulation tests for head and knee bolster are carried out to meet the regulation of FMVSS 201 and FMVSS 208, respectively. NVH analysis is performed to obtain mainly the natural frequencies and corresponding mode shapes, while the crashworthiness analysis is employed to examine the crash behavior of IP structure. With the consideration of lightweight, NVH, head and knee bolster impact performance, design of experiment(DOE), response surface model(RSM), and collaborative optimization(CO) are applied to realize the determined and reliability-based optimizations, respectively. Furthermore, based on multi-objective genetic algorithm(MOGA), the optimal Pareto sets are completed to solve the multi-objective optimization(MOO) problem. The proposed research ensures the smoothness of Pareto set, enhances the ability of engineers to make a comprehensive decision about multi-objectives and choose the optimal design, and improves the quality and efficiency of MDO.

A terrain-based paired-site sampling design to assess biodiversity losses from eastern hemlock decline

USGS Publications Warehouse

Young, J.A.; Smith, D.R.; Snyder, C.D.; Lemarie, D.P.

2002-01-01

Biodiversity surveys are often hampered by the inability to control extraneous sources of variability introduced into comparisons of populations across a heterogenous landscape. If not specifically accounted for a priori, this noise can weaken comparisons between sites, and can make it difficult to draw inferences about specific ecological processes. We developed a terrain-based, paired-site sampling design to analyze differences in aquatic biodiversity between streams draining eastern hemlock (Tsuga canadensis) forests, and those draining mixed hardwood forests in Delaware Water Gap National Recreation Area (USA). The goal of this design was to minimize variance due to terrain influences on stream communities, while representing the range of hemlock dominated stream environments present in the park. We used geographic information systems (GIS) and cluster analysis to define and partition hemlock dominated streams into terrain types based on topographic variables and stream order. We computed similarity of forest stands within terrain types and used this information to pair hemlock-dominated streams with hardwood counterparts prior to sampling. We evaluated the effectiveness of the design through power analysis and found that power to detect differences in aquatic invertebrate taxa richness was highest when sites were paired and terrain type was included as a factor in the analysis. Precision of the estimated difference in mean richness was nearly doubled using the terrain-based, paired site design in comparison to other evaluated designs. Use of this method allowed us to sample stream communities representative of park-wide forest conditions while effectively controlling for landscape variability.

Performance analysis of a coherent free space optical communication system based on experiment.

PubMed

Cao, Jingtai; Zhao, Xiaohui; Liu, Wei; Gu, Haijun

2017-06-26

Based on our previous study and designed experimental AO system with a 97-element continuous surface deformable mirror, we conduct the performance analysis of a coherent free space optical communication (FSOC) system for mixing efficiency (ME), bit error rate (BER) and outage probability under different Greenwood frequency and atmospheric coherent length. The results show that the influence of the atmospheric temporal characteristics on the performance is slightly stronger than that of the spatial characteristics when the receiving aperture and the number of sub-apertures are given. This analysis result provides a reference for the design of the coherent FSOC system.

Molecular beacon sequence design algorithm.

PubMed

Monroe, W Todd; Haselton, Frederick R

2003-01-01

A method based on Web-based tools is presented to design optimally functioning molecular beacons. Molecular beacons, fluorogenic hybridization probes, are a powerful tool for the rapid and specific detection of a particular nucleic acid sequence. However, their synthesis costs can be considerable. Since molecular beacon performance is based on its sequence, it is imperative to rationally design an optimal sequence before synthesis. The algorithm presented here uses simple Microsoft Excel formulas and macros to rank candidate sequences. This analysis is carried out using mfold structural predictions along with other free Web-based tools. For smaller laboratories where molecular beacons are not the focus of research, the public domain algorithm described here may be usefully employed to aid in molecular beacon design.

Design Criteria For Networked Image Analysis System

NASA Astrophysics Data System (ADS)

Reader, Cliff; Nitteberg, Alan

1982-01-01

Image systems design is currently undergoing a metamorphosis from the conventional computing systems of the past into a new generation of special purpose designs. This change is motivated by several factors, notably among which is the increased opportunity for high performance with low cost offered by advances in semiconductor technology. Another key issue is a maturing in understanding of problems and the applicability of digital processing techniques. These factors allow the design of cost-effective systems that are functionally dedicated to specific applications and used in a utilitarian fashion. Following an overview of the above stated issues, the paper presents a top-down approach to the design of networked image analysis systems. The requirements for such a system are presented, with orientation toward the hospital environment. The three main areas are image data base management, viewing of image data and image data processing. This is followed by a survey of the current state of the art, covering image display systems, data base techniques, communications networks and software systems control. The paper concludes with a description of the functional subystems and architectural framework for networked image analysis in a production environment.

Design of Computer-aided Instruction for Radiology Interpretation: The Role of Cognitive Task Analysis

PubMed Central

Pusic, Martin V.; LeBlanc, Vicki; Patel, Vimla L.

2001-01-01

Traditional task analysis for instructional design has emphasized the importance of precisely defining behavioral educational objectives and working back to select objective-appropriate instructional strategies. However, this approach may miss effective strategies. Cognitive task analysis, on the other hand, breaks a process down into its component knowledge representations. Selection of instructional strategies based on all such representations in a domain is likely to lead to optimal instructional design. In this demonstration, using the interpretation of cervical spine x-rays as an educational example, we show how a detailed cognitive task analysis can guide the development of computer-aided instruction.

Preliminary Design of ICI-based Multimedia for Reconceptualizing Electric Conceptions at Universitas Pendidikan Indonesia

NASA Astrophysics Data System (ADS)

Samsudin, A.; Suhandi, A.; Rusdiana, D.; Kaniawati, I.

2016-08-01

Interactive Conceptual Instruction (ICI) based Multimedia has been developed to represent the electric concepts turn into more real and meaningful learning. The initial design of ICI based multimedia is a multimedia computer that allows users to explore the entire electric concepts in terms of the existing conceptual and practical. Pre-service physics teachers should be provided with the learning that could optimize the conceptions held by re-conceptualizing concepts in Basic Physics II, especially the concepts about electricity. To collect and to analyze the data genuinely and comprehensively, researchers utilized a developing method of ADDIE which has comprehensive steps: analyzing, design, development, implementation, and evaluation. The ADDIE developing steps has been utilized to describe comprehensively from the phase of analysis program up until the evaluation program. Based on data analysis, it can be concluded that ICI-based multimedia could effectively increase the pre-service physics teachers’ understanding on electric conceptions for re-conceptualizing electric conceptions at Universitas Pendidikan Indonesia.

Reliability based design optimization: Formulations and methodologies

NASA Astrophysics Data System (ADS)

Agarwal, Harish

Modern products ranging from simple components to complex systems should be designed to be optimal and reliable. The challenge of modern engineering is to ensure that manufacturing costs are reduced and design cycle times are minimized while achieving requirements for performance and reliability. If the market for the product is competitive, improved quality and reliability can generate very strong competitive advantages. Simulation based design plays an important role in designing almost any kind of automotive, aerospace, and consumer products under these competitive conditions. Single discipline simulations used for analysis are being coupled together to create complex coupled simulation tools. This investigation focuses on the development of efficient and robust methodologies for reliability based design optimization in a simulation based design environment. Original contributions of this research are the development of a novel efficient and robust unilevel methodology for reliability based design optimization, the development of an innovative decoupled reliability based design optimization methodology, the application of homotopy techniques in unilevel reliability based design optimization methodology, and the development of a new framework for reliability based design optimization under epistemic uncertainty. The unilevel methodology for reliability based design optimization is shown to be mathematically equivalent to the traditional nested formulation. Numerical test problems show that the unilevel methodology can reduce computational cost by at least 50% as compared to the nested approach. The decoupled reliability based design optimization methodology is an approximate technique to obtain consistent reliable designs at lesser computational expense. Test problems show that the methodology is computationally efficient compared to the nested approach. A framework for performing reliability based design optimization under epistemic uncertainty is also developed. A trust region managed sequential approximate optimization methodology is employed for this purpose. Results from numerical test studies indicate that the methodology can be used for performing design optimization under severe uncertainty.

Stiffness Parameter Design of Suspension Element of Under-Chassis-Equipment for A Rail Vehicle

NASA Astrophysics Data System (ADS)

Ma, Menglin; Wang, Chengqiang; Deng, Hai

2017-06-01

According to the frequency configuration requirements of the vibration of railway under-chassis-equipment, the three- dimension stiffness of the suspension elements of under-chassis-equipment is designed based on the static principle and dynamics principle. The design results of the concrete engineering case show that, compared with the design method based on the static principle, the three- dimension stiffness of the suspension elements designed by the dynamic principle design method is more uniform. The frequency and decoupling degree analysis show that the calculation frequency of under-chassis-equipment under the two design methods is basically the same as the predetermined frequency. Compared with the design method based on the static principle, the design method based on the dynamic principle is adopted. The decoupling degree can be kept high, and the coupling vibration of the corresponding vibration mode can be reduced effectively, which can effectively reduce the fatigue damage of the key parts of the hanging element.

The use of optimization techniques to design controlled diffusion compressor blading

NASA Technical Reports Server (NTRS)

Sanger, N. L.

1982-01-01

A method for automating compressor blade design using numerical optimization, and applied to the design of a controlled diffusion stator blade row is presented. A general purpose optimization procedure is employed, based on conjugate directions for locally unconstrained problems and on feasible directions for locally constrained problems. Coupled to the optimizer is an analysis package consisting of three analysis programs which calculate blade geometry, inviscid flow, and blade surface boundary layers. The optimizing concepts and selection of design objective and constraints are described. The procedure for automating the design of a two dimensional blade section is discussed, and design results are presented.

Analysis of Design Parameters Effects on Vibration Characteristics of Fluidlastic Isolators

NASA Astrophysics Data System (ADS)

Deng, Jing-hui; Cheng, Qi-you

2017-07-01

The control of vibration in helicopters which consists of reducing vibration levels below the acceptable limit is one of the key problems. The fluidlastic isolators become more and more widely used because the fluids are non-toxic, non-corrosive, nonflammable, and compatible with most elastomers and adhesives. In the field of the fluidlastic isolators design, the selection of design parameters is very important to obtain efficient vibration-suppressed. Aiming at getting the effect of design parameters on the property of fluidlastic isolator, a dynamic equation is set up based on the theory of dynamics. And the dynamic analysis is carried out. The influences of design parameters on the property of fluidlastic isolator are calculated. Dynamic analysis results have shown that fluidlastic isolator can reduce the vibration effectively. Analysis results also showed that the design parameters such as the fluid density, viscosity coefficient, stiffness (K1 and K2) and loss coefficient have obvious influence on the performance of isolator. The efficient vibration-suppressed can be obtained by the design optimization of parameters.

Design and Analysis of Tooth Impact Test Rig for Spur Gear

NASA Astrophysics Data System (ADS)

Ghazali, Wafiuddin Bin Md; Aziz, Ismail Ali Bin Abdul; Daing Idris, Daing Mohamad Nafiz Bin; Ismail, Nurazima Binti; Sofian, Azizul Helmi Bin

2016-02-01

This paper is about the design and analysis of a prototype of tooth impact test rig for spur gear. The test rig was fabricated and analysis was conducted to study its’ limitation and capabilities. The design of the rig is analysed to ensure that there will be no problem occurring during the test and reliable data can be obtained. From the result of the analysis, the maximum amount of load that can be applied, the factor of safety of the machine, the stresses on the test rig parts were determined. This is important in the design consideration of the test rig. The materials used for the fabrication of the test rig were also discussed and analysed. MSC Nastran Patran software was used to analyse the model, which was designed by using SolidWorks 2014 software. Based from the results, there were limitations found from the initial design and the test rig design needs to be improved in order for the test rig to operate properly.

Matches, Mismatches, and Methods: Multiple-View Workflows for Energy Portfolio Analysis.

PubMed

Brehmer, Matthew; Ng, Jocelyn; Tate, Kevin; Munzner, Tamara

2016-01-01

The energy performance of large building portfolios is challenging to analyze and monitor, as current analysis tools are not scalable or they present derived and aggregated data at too coarse of a level. We conducted a visualization design study, beginning with a thorough work domain analysis and a characterization of data and task abstractions. We describe generalizable visual encoding design choices for time-oriented data framed in terms of matches and mismatches, as well as considerations for workflow design. Our designs address several research questions pertaining to scalability, view coordination, and the inappropriateness of line charts for derived and aggregated data due to a combination of data semantics and domain convention. We also present guidelines relating to familiarity and trust, as well as methodological considerations for visualization design studies. Our designs were adopted by our collaborators and incorporated into the design of an energy analysis software application that will be deployed to tens of thousands of energy workers in their client base.

Derivation of Design Loads and Random Vibration specifications for Spacecraft Instruments and Sub-Units

NASA Astrophysics Data System (ADS)

Fransen, S.; Yamawaki, T.; Akagi, H.; Eggens, M.; van Baren, C.

2014-06-01

After a first estimation based on statistics, the design loads for instruments are generally estimated by coupled spacecraft/instrument sine analysis once an FE-model of the spacecraft is available. When the design loads for the instrument have been derived, the next step in the process is to estimate the random vibration environment at the instrument base and to compute the RMS load at the centre of gravity of the instrument by means of vibro-acoustic analysis. Finally the design loads of the light-weight sub-units of the instrument can be estimated through random vibration analysis at instrument level, taking into account the notches required to protect the instrument interfaces in the hard- mounted random vibration test. This paper presents the aforementioned steps of instrument and sub-units loads derivation in the preliminary design phase of the spacecraft and identifies the problems that may be encountered in terms of design load consistency between low-frequency and high-frequency environments. The SpicA FAR-infrared Instrument (SAFARI) which is currently developed for the Space Infrared Telescope for Cosmology and Astrophysics (SPICA) will be used as a guiding example.

Non-Linear Vibroisolation Pads Design, Numerical FEM Analysis and Introductory Experimental Investigations

NASA Astrophysics Data System (ADS)

Zielnica, J.; Ziółkowski, A.; Cempel, C.

2003-03-01

Design and theoretical and experimental investigation of vibroisolation pads with non-linear static and dynamic responses is the objective of the paper. The analytical investigations are based on non-linear finite element analysis where the load-deflection response is traced against the shape and material properties of the analysed model of the vibroisolation pad. A new model of vibroisolation pad of antisymmetrical type was designed and analysed by the finite element method based on the second-order theory (large displacements and strains) with the assumption of material's non-linearities (Mooney-Rivlin model). Stability loss phenomenon was used in the design of the vibroisolators, and it was proved that it would be possible to design a model of vibroisolator in the form of a continuous pad with non-linear static and dynamic response, typical to vibroisolation purposes. The materials used for the vibroisolator are those of rubber, elastomers, and similar ones. The results of theoretical investigations were examined experimentally. A series of models made of soft rubber were designed for the test purposes. The experimental investigations of the vibroisolation models, under static and dynamic loads, confirmed the results of the FEM analysis.

Microcomputer design and analysis of the cable catenary large space antenna system

NASA Technical Reports Server (NTRS)

Akle, W.

1984-01-01

The use of microcomputers in the design of a cable catenary large space antenna system is discussed. The development of a system design capability, data base utilization, systems integration, program structure and logic, and integrated graphics output are discussed.

Logic Design Pathology and Space Flight Electronics

NASA Technical Reports Server (NTRS)

Katz, Richard B.; Barto, Rod L.; Erickson, Ken

1999-01-01

This paper presents a look at logic design from early in the US Space Program and examines faults in recent logic designs. Most examples are based on flight hardware failures and analysis of new tools and techniques. The paper is presented in viewgraph form.

AHP based Anthropometric Analysis of University Hall Bed Design in Bangladesh

NASA Astrophysics Data System (ADS)

Halder, Pobitra; Sarker, Eity; Karmaker, Chitralekha

2018-05-01

In university hall, different types of bed are used for providing sleeping environment to the students. Although there are wide variations in the design of students' bed in Bangladeshi university hall, none of them are designed properly considering the anthropometric data. In this study, four anthropometric measurements related to normal students' bed dimensions were measured from 300 students from a public university hall in Bangladesh. The feedbacks regarding different health problems and their reasons were collected from considering practical situations of the students and gathering experts' opinions. Chi-square test showed that back pain, blood circulation problem, fatigue, comfort, and sleeping problem are related to students' anthropometric measurements. The analytic hierarchy process (AHP) analysis identified students' bed length as the most responsible attribute for ergonomic problems of the students. Finally, the linear regression and correlation analysis suggested the bed dimensions based on stature of the students. This study can be a helpful guideline for industrial engineers and manufacturers in designing more comfortable students' bed.

A Performance-Based Training Qualification Guide/Checklist Developed for Reactor Operators at the High Flux Beam Reactor at Brookhaven National Laboratory.

ERIC Educational Resources Information Center

McNair, Robert C.

A Performance-Based Training (PBT) Qualification Guide/Checklist was developed that would enable a trainee to attain the skills, knowledge, and attitude required to operate the High Flux Beam Reactor at Brookhaven National Laboratory. Design of this guide/checklist was based on the Instructional System Design Model. The needs analysis identified…

[Design of a Front-end Device of Heart Rate Variability Analysis System Based on Photoplethysmography].

PubMed

Shi, Lei; Sun, Peng; Pang, Yu; Luo, Zhiyong; Wang, Wei; Wang, Yanxiang

2016-02-01

Heart rate variability (HRV) is the difference between the successive changes in the heartbeat cycle, and it is produced in the autonomic nervous system modulation of the sinus node of the heart. The HRV is a valuable indicator in predicting the sudden cardiac death and arrhythmic events. Traditional analysis of HRV is based on a multielectrocardiogram (ECG), but the ECG signal acquisition is complex, so we have designed an HRV analysis system based on photoplethysmography (PPG). PPG signal is collected by a microcontroller from human's finger, and it is sent to the terminal via USB-Serial module. The terminal software not only collects the data and plot waveforms, but also stores the data for future HRV analysis. The system is small in size, low in power consumption, and easy for operation. It is suitable for daily care no matter whether it is used at home or in a hospital.

Sensitivity analysis and approximation methods for general eigenvalue problems

NASA Technical Reports Server (NTRS)

Murthy, D. V.; Haftka, R. T.

1986-01-01

Optimization of dynamic systems involving complex non-hermitian matrices is often computationally expensive. Major contributors to the computational expense are the sensitivity analysis and reanalysis of a modified design. The present work seeks to alleviate this computational burden by identifying efficient sensitivity analysis and approximate reanalysis methods. For the algebraic eigenvalue problem involving non-hermitian matrices, algorithms for sensitivity analysis and approximate reanalysis are classified, compared and evaluated for efficiency and accuracy. Proper eigenvector normalization is discussed. An improved method for calculating derivatives of eigenvectors is proposed based on a more rational normalization condition and taking advantage of matrix sparsity. Important numerical aspects of this method are also discussed. To alleviate the problem of reanalysis, various approximation methods for eigenvalues are proposed and evaluated. Linear and quadratic approximations are based directly on the Taylor series. Several approximation methods are developed based on the generalized Rayleigh quotient for the eigenvalue problem. Approximation methods based on trace theorem give high accuracy without needing any derivatives. Operation counts for the computation of the approximations are given. General recommendations are made for the selection of appropriate approximation technique as a function of the matrix size, number of design variables, number of eigenvalues of interest and the number of design points at which approximation is sought.

Analysis and design of negative resistance oscillators using surface transverse wave-based single port resonators.

PubMed

Avramov, Ivan D

2003-03-01

This practically oriented paper presents the fundamentals for analysis, optimization, and design of negative resistance oscillators (NRO) stabilized with surface transverse wave (STW)-based single-port resonators (SPR). Data on a variety of high-Q, low-loss SPR devices in the 900- to 2000-MHz range, suitable for NRO applications, are presented, and a simple method for SPR parameter extraction through Pi-circuit measurements is outlined. Negative resistance analysis, based on S-parameter data of the active device, is performed on a tuned-base, grounded collector transistor NRO, known for its good stability and tuning at microwave frequencies. By adding a SPR in the emitter network, the static transducer capacitance is absorbed by the circuit and is used to generate negative resistance only over the narrow bandwidth of the acoustic device, eliminating the risk of spurious oscillations. The analysis allows exact prediction of the oscillation frequency, tuning range, loaded Q, and excess gain. Simulation and experimental data on a 915-MHz fixed-frequency NRO and a wide tuning range, voltage-controlled STW oscillator, built and tested experimentally, are presented. Practical design aspects including the choice of transistor, negative feedback circuits, load coupling, and operation at the highest phase slope for minimum phase noise are discussed.

Simulation-based analysis of performance parameters of microstrip antennas with criss-cross metamaterial-based artificial substrate

NASA Astrophysics Data System (ADS)

Inamdar, Kirti; Kosta, Y. P.; Patnaik, S.

2014-10-01

In this paper, we present the design of a metamaterial-based microstrip patch antenna, optimized for bandwidth and multiple frequency operations. A criss-cross structure has been proposed, this shape has been inspired from the famous Jerusalem cross. The theory and design formulas to calculate various parameters of the proposed antenna have been presented. Design starts with the analysis of the proposed unit cell structure, and validating the response using software- HFSS Version 13, to obtain negative response of ε and μ- metamaterial. Following this, a metamaterial-based-microstrip-patch-antenna is designed. A detailed comparative study is conducted exploring the response of the designed patch made of metamaterial and that of the conventional patch. Finally, antenna parameters such as gain, bandwidth, radiation pattern, and multiple frequency responses are investigated and optimised for the same and present in table and response graphs. It is also observed that the physical dimension of the metamaterial-based patch antenna is smaller compared to its conventional counterpart operating at the same fundamental frequency. The challenging part was to develop metamaterial based on some signature structures and techniques that would offer advantage in terms of BW and multiple frequency operation, which is demonstrated in this paper. The unique shape proposed in this paper gives improvement in bandwidth without reducing the gain of the antenna.

A Bayesian Framework for Analysis of Pseudo-Spatial Models of Comparable Engineered Systems with Application to Spacecraft Anomaly Prediction Based on Precedent Data

NASA Astrophysics Data System (ADS)

Ndu, Obibobi Kamtochukwu

To ensure that estimates of risk and reliability inform design and resource allocation decisions in the development of complex engineering systems, early engagement in the design life cycle is necessary. An unfortunate constraint on the accuracy of such estimates at this stage of concept development is the limited amount of high fidelity design and failure information available on the actual system under development. Applying the human ability to learn from experience and augment our state of knowledge to evolve better solutions mitigates this limitation. However, the challenge lies in formalizing a methodology that takes this highly abstract, but fundamentally human cognitive, ability and extending it to the field of risk analysis while maintaining the tenets of generalization, Bayesian inference, and probabilistic risk analysis. We introduce an integrated framework for inferring the reliability, or other probabilistic measures of interest, of a new system or a conceptual variant of an existing system. Abstractly, our framework is based on learning from the performance of precedent designs and then applying the acquired knowledge, appropriately adjusted based on degree of relevance, to the inference process. This dissertation presents a method for inferring properties of the conceptual variant using a pseudo-spatial model that describes the spatial configuration of the family of systems to which the concept belongs. Through non-metric multidimensional scaling, we formulate the pseudo-spatial model based on rank-ordered subjective expert perception of design similarity between systems that elucidate the psychological space of the family. By a novel extension of Kriging methods for analysis of geospatial data to our "pseudo-space of comparable engineered systems", we develop a Bayesian inference model that allows prediction of the probabilistic measure of interest.

Observer-based distributed adaptive iterative learning control for linear multi-agent systems

NASA Astrophysics Data System (ADS)

Li, Jinsha; Liu, Sanyang; Li, Junmin

2017-10-01

This paper investigates the consensus problem for linear multi-agent systems from the viewpoint of two-dimensional systems when the state information of each agent is not available. Observer-based fully distributed adaptive iterative learning protocol is designed in this paper. A local observer is designed for each agent and it is shown that without using any global information about the communication graph, all agents achieve consensus perfectly for all undirected connected communication graph when the number of iterations tends to infinity. The Lyapunov-like energy function is employed to facilitate the learning protocol design and property analysis. Finally, simulation example is given to illustrate the theoretical analysis.

Interactive Graphics Simulator: Design, Development, and Effectiveness/Cost Evaluation. Final Report.

ERIC Educational Resources Information Center

Pieper, William J.; And Others

This study was initiated to design, develop, implement, and evaluate a videodisc-based simulator system, the Interactive Graphics Simulator (IGS) for 6883 Converter Flight Control Test Station training at Lowry Air Force Base, Colorado. The simulator provided a means for performing task analysis online, developing simulations from the task…

Analysis of Students' Participation Patterns and Learning Presence in a Wiki-Based Project

ERIC Educational Resources Information Center

Roussinos, Dimitrios; Jimoyiannis, Athanassios

2013-01-01

The educational applications of wikis are becoming very popular among instructors and researchers and they have captured their attention and imagination. This paper reports on the investigation of a wiki project designed to support university students' collaborative authoring and learning. The design framework of the wiki-based project is outlined…

Design of overlays based on pavement condition, roughness, and deflections : part 1 : tentative method for overlay design based on visual pavement distress.

DOT National Transportation Integrated Search

1978-01-01

Data collected on 111 interstate highway projects in Virginia were analyzed by multi-regression analysis and the rating coefficient for each type of distress determined. By this means, the total pavement distress and, hence, the maintenance rating of...

Exploring Small Group Analysis of Instructional Design Cases in Online Learning Environments

ERIC Educational Resources Information Center

Trespalacios, Jesus

2017-01-01

The case-based approach is a constructivist instructional strategy that helps students apply their emerging knowledge by studying design problems in authentic real-world situations. One important instructional strategy in case-based instruction is to analyze cases in small groups before discussing them with the whole class. This study investigates…

Game-Based Learning in Science Education: A Review of Relevant Research

ERIC Educational Resources Information Center

Li, Ming-Chaun; Tsai, Chin-Chung

2013-01-01

The purpose of this study is to review empirical research articles regarding game-based science learning (GBSL) published from 2000 to 2011. Thirty-one articles were identified through the Web of Science and SCOPUS databases. A qualitative content analysis technique was adopted to analyze the research purposes and designs, game design and…

Automotive Technician. A Competency-Based Curriculum Designed To Prepare Students for Entry-Level Employment.

ERIC Educational Resources Information Center

Vocational Curriculum Resource Center of Maine, Fairfield.

This curriculum guide is designed to assist instructors in the development and implementation of a comprehensive, competency-based automotive curriculum. It contains an instructional unit for each task listed on the enclosed job analysis or DACUM (Developing a Curriculum) chart. These units include introduction, performance objectives, suggested…

Strategic Industrial Alliances in Paper Industry: XML- vs Ontology-Based Integration Platforms

ERIC Educational Resources Information Center

Naumenko, Anton; Nikitin, Sergiy; Terziyan, Vagan; Zharko, Andriy

2005-01-01

Purpose: To identify cases related to design of ICT platforms for industrial alliances, where the use of Ontology-driven architectures based on Semantic web standards is more advantageous than application of conventional modeling together with XML standards. Design/methodology/approach: A comparative analysis of the two latest and the most obvious…

X-33 Base Region Thermal Protection System Design Study

NASA Technical Reports Server (NTRS)

Lycans, Randal W.

1998-01-01

The X-33 is an advanced technology demonstrator for validating critical technologies and systems required for an operational Single-Stage-to-Orbit (SSTO) Reusuable Launch Vehicle (RLV). Currently under development by a unique contractor/government team led by Lockheed- Martin Skunk Works (LMSW), and managed by Marshall Space Flight Center (MSFC), the X-33 will be the prototype of the first new launch system developed by the United States since the advent of the space shuttle. This paper documents a design trade study of the X-33 base region thermal protection system (TPS). Two candidate designs were evaluated for thermal performance and weight. The first candidate was a fully reusable metallic TPS using Inconel honeycomb panels insulated with high temperature fibrous insulation, while the second was an ablator/insulator sprayed on the metallic skin of the vehicle. The TPS configurations and insulation thickness requirements were determined for the predicted main engine plume heating environments and base region entry aerothermal environments. In addition to thermal analysis of the design concepts, sensitivity studies were performed to investigate the effect of variations in key parameters of the base TPS analysis.

Research on animation design of growing plant based on 3D MAX technology

NASA Astrophysics Data System (ADS)

Chen, Yineng; Fang, Kui; Bu, Weiqiong; Zhang, Xiaoling; Lei, Menglong

In view of virtual plant has practical demands on quality, image and degree of realism animation in growing process of plant, this thesis design the animation based on mechanism and regularity of plant growth, and propose the design method based on 3D MAX technology. After repeated analysis and testing, it is concluded that there are modeling, rendering, animation fabrication and other key technologies in the animation design process. Based on this, designers can subdivid the animation into seed germination animation, plant growth prophase animation, catagen animation, later animation and blossom animation. This paper compounds the animation of these five stages by VP window to realize the completed 3D animation. Experimental result shows that the animation can realized rapid, visual and realistic simulatation the plant growth process.

Didactic trajectory of research in mathematics education using research-based learning

NASA Astrophysics Data System (ADS)

Charitas Indra Prahmana, Rully; Kusumah, Yaya S.; Darhim

2017-10-01

This study aims to describe the role of research-based learning in design a learning trajectory of research in mathematics education to enhance research and academic writing skills for pre-service mathematics teachers. The method used is a design research with three stages, namely the preliminary design, teaching experiment, and retrospective analysis. The research subjects are pre-service mathematics teacher class of 2012 from one higher education institution in Tangerang - Indonesia. The use of research-based learning in designing learning trajectory of research in mathematics education plays a crucial role as a trigger to enhancing math department preservice teachers research and academic writing skills. Also, this study also describes the design principles and characteristics of the learning trajectory namely didactic trajectory generated by the role of research-based learning syntax.

Analysis on the workspace of palletizing robot based on AutoCAD

NASA Astrophysics Data System (ADS)

Li, Jin-quan; Zhang, Rui; Guan, Qi; Cui, Fang; Chen, Kuan

2017-10-01

In this paper, a four-degree-of-freedom articulated palletizing robot is used as the object of research. Based on the analysis of the overall configuration of the robot, the kinematic mathematical model is established by D-H method to figure out the workspace of the robot. In order to meet the needs of design and analysis, using AutoCAD secondary development technology and AutoLisp language to develop AutoCAD-based 2D and 3D workspace simulation interface program of palletizing robot. At last, using AutoCAD plugin, the influence of structural parameters on the shape and position of the working space is analyzed when the structure parameters of the robot are changed separately. This study laid the foundation for the design, control and planning of palletizing robots.

Orbit Determination Toolbox

NASA Technical Reports Server (NTRS)

Carpenter, James R.; Berry, Kevin; Gregpru. Late; Speckman, Keith; Hur-Diaz, Sun; Surka, Derek; Gaylor, Dave

2010-01-01

The Orbit Determination Toolbox is an orbit determination (OD) analysis tool based on MATLAB and Java that provides a flexible way to do early mission analysis. The toolbox is primarily intended for advanced mission analysis such as might be performed in concept exploration, proposal, early design phase, or rapid design center environments. The emphasis is on flexibility, but it has enough fidelity to produce credible results. Insight into all flight dynamics source code is provided. MATLAB is the primary user interface and is used for piecing together measurement and dynamic models. The Java Astrodynamics Toolbox is used as an engine for things that might be slow or inefficient in MATLAB, such as high-fidelity trajectory propagation, lunar and planetary ephemeris look-ups, precession, nutation, polar motion calculations, ephemeris file parsing, and the like. The primary analysis functions are sequential filter/smoother and batch least-squares commands that incorporate Monte-Carlo data simulation, linear covariance analysis, measurement processing, and plotting capabilities at the generic level. These functions have a user interface that is based on that of the MATLAB ODE suite. To perform a specific analysis, users write MATLAB functions that implement truth and design system models. The user provides his or her models as inputs to the filter commands. The software provides a capability to publish and subscribe to a software bus that is compliant with the NASA Goddard Mission Services Evolution Center (GMSEC) standards, to exchange data with other flight dynamics tools to simplify the flight dynamics design cycle. Using the publish and subscribe approach allows for analysts in a rapid design center environment to seamlessly incorporate changes in spacecraft and mission design into navigation analysis and vice versa.

Integration of design, structural, thermal and optical analysis: And user's guide for structural-to-optical translator (PATCOD)

NASA Technical Reports Server (NTRS)

Amundsen, R. M.; Feldhaus, W. S.; Little, A. D.; Mitchum, M. V.

1995-01-01

Electronic integration of design and analysis processes was achieved and refined at Langley Research Center (LaRC) during the development of an optical bench for a laser-based aerospace experiment. Mechanical design has been integrated with thermal, structural and optical analyses. Electronic import of the model geometry eliminates the repetitive steps of geometry input to develop each analysis model, leading to faster and more accurate analyses. Guidelines for integrated model development are given. This integrated analysis process has been built around software that was already in use by designers and analysis at LaRC. The process as currently implemented used Pro/Engineer for design, Pro/Manufacturing for fabrication, PATRAN for solid modeling, NASTRAN for structural analysis, SINDA-85 and P/Thermal for thermal analysis, and Code V for optical analysis. Currently, the only analysis model to be built manually is the Code V model; all others can be imported for the Pro/E geometry. The translator from PATRAN results to Code V optical analysis (PATCOD) was developed and tested at LaRC. Directions for use of the translator or other models are given.

Terrestrial Planet Finder Coronagraph Observatory summary

NASA Technical Reports Server (NTRS)

Ford, Virginia; Levine-Westa, Marie; Kissila, Andy; Kwacka, Eug; Hoa, Tim; Dumonta, Phil; Lismana, Doug; Fehera, Peter; Cafferty, Terry

2005-01-01

Creating an optical space telescope observatory capable of detecting and characterizing light from extra-solar terrestrial planets poses technical challenges related to extreme wavefront stability. The Terrestrial Planet Finder Coronagraph design team has been developing an observatory based on trade studies, modeling and analysis that has guided us towards design choices to enable this challenging mission. This paper will describe the current flight baseline design of the observatory and the trade studies that have been performed. The modeling and analysis of this design will be described including predicted performance and the tasks yet to be done.

Tribology symposium -- 1994. PD-Volume 61

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

Masudi, H.

This year marks the first Tribology Symposium within the Energy-Sources Technology Conference, sponsored by the ASME Petroleum Division. The program was divided into five sessions: Tribology in High Technology, a historical discussion of some watershed events in tribology; Research/Development, design, research and development on modern manufacturing; Tribology in Manufacturing, the impact of tribology on modern manufacturing; Design/Design Representation, aspects of design related to tribological systems; and Failure Analysis, an analysis of failure, failure detection, and failure monitoring as relating to manufacturing processes. Eleven papers have been processed separately for inclusion on the data base.

[Adequate application of quantitative and qualitative statistic analytic methods in acupuncture clinical trials].

PubMed

Tan, Ming T; Liu, Jian-ping; Lao, Lixing

2012-08-01

Recently, proper use of the statistical methods in traditional Chinese medicine (TCM) randomized controlled trials (RCTs) has received increased attention. Statistical inference based on hypothesis testing is the foundation of clinical trials and evidence-based medicine. In this article, the authors described the methodological differences between literature published in Chinese and Western journals in the design and analysis of acupuncture RCTs and the application of basic statistical principles. In China, qualitative analysis method has been widely used in acupuncture and TCM clinical trials, while the between-group quantitative analysis methods on clinical symptom scores are commonly used in the West. The evidence for and against these analytical differences were discussed based on the data of RCTs assessing acupuncture for pain relief. The authors concluded that although both methods have their unique advantages, quantitative analysis should be used as the primary analysis while qualitative analysis can be a secondary criterion for analysis. The purpose of this paper is to inspire further discussion of such special issues in clinical research design and thus contribute to the increased scientific rigor of TCM research.

Participatory Design of an Integrated Information System Design to Support Public Health Nurses and Nurse Managers

PubMed Central

Reeder, Blaine; Hills, Rebecca A.; Turner, Anne M.; Demiris, George

2014-01-01

Objectives The objectives of the study were to use persona-driven and scenario-based design methods to create a conceptual information system design to support public health nursing. Design and Sample We enrolled 19 participants from two local health departments to conduct an information needs assessment, create a conceptual design, and conduct a preliminary design validation. Measures Interviews and thematic analysis were used to characterize information needs and solicit design recommendations from participants. Personas were constructed from participant background information, and scenario-based design was used to create a conceptual information system design. Two focus groups were conducted as a first iteration validation of information needs, personas, and scenarios. Results Eighty-nine information needs were identified. Two personas and 89 scenarios were created. Public health nurses and nurse managers confirmed the accuracy of information needs, personas, scenarios, and the perceived usefulness of proposed features of the conceptual design. Design artifacts were modified based on focus group results. Conclusion Persona-driven design and scenario-based design are feasible methods to design for common work activities in different local health departments. Public health nurses and nurse managers should be engaged in the design of systems that support their work. PMID:24117760

Embracing model-based designs for dose-finding trials

PubMed Central

Love, Sharon B; Brown, Sarah; Weir, Christopher J; Harbron, Chris; Yap, Christina; Gaschler-Markefski, Birgit; Matcham, James; Caffrey, Louise; McKevitt, Christopher; Clive, Sally; Craddock, Charlie; Spicer, James; Cornelius, Victoria

2017-01-01

Background: Dose-finding trials are essential to drug development as they establish recommended doses for later-phase testing. We aim to motivate wider use of model-based designs for dose finding, such as the continual reassessment method (CRM). Methods: We carried out a literature review of dose-finding designs and conducted a survey to identify perceived barriers to their implementation. Results: We describe the benefits of model-based designs (flexibility, superior operating characteristics, extended scope), their current uptake, and existing resources. The most prominent barriers to implementation of a model-based design were lack of suitable training, chief investigators’ preference for algorithm-based designs (e.g., 3+3), and limited resources for study design before funding. We use a real-world example to illustrate how these barriers can be overcome. Conclusions: There is overwhelming evidence for the benefits of CRM. Many leading pharmaceutical companies routinely implement model-based designs. Our analysis identified barriers for academic statisticians and clinical academics in mirroring the progress industry has made in trial design. Unified support from funders, regulators, and journal editors could result in more accurate doses for later-phase testing, and increase the efficiency and success of clinical drug development. We give recommendations for increasing the uptake of model-based designs for dose-finding trials in academia. PMID:28664918

Ergonomic Based Design and Survey of Elementary School Furniture

ERIC Educational Resources Information Center

Maheshwar; Jawalkar, Chandrashekhar S.

2014-01-01

This paper presents the ergonomic aspects in designing and prototyping of desks cum chairs used in elementary schools. The procedures adopted for the assessment included: the study of existing school furniture, design analysis and development of prototypes. The design approach proposed a series of adjustable desks and chairs developed in terms of…

Information Design: A New Approach to Teaching Technical Writing Service Courses

ERIC Educational Resources Information Center

McKee, Candie DeLane

2012-01-01

This study used a needs assessment, process analysis, process design, and textbook design to develop a new process and new textbook, based on Cargile-Cook's layered literacies, Quesenbery's five qualities of usability, and Carliner's information design theories, for use in technical writing service learning courses. The needs assessment was based…

A Design Quality Learning Unit in Relational Data Modeling Based on Thriving Systems Properties

ERIC Educational Resources Information Center

Waguespack, Leslie J.

2013-01-01

This paper presents a learning unit that addresses quality design in relational data models. The focus on modeling allows the learning to span analysis, design, and implementation enriching pedagogy across the systems development life cycle. Thriving Systems Theory presents fifteen choice properties that convey design quality in models integrating…

Mars Mission Analysis Trades Based on Legacy and Future Nuclear Propulsion Options

NASA Astrophysics Data System (ADS)

Joyner, Russell; Lentati, Andrea; Cichon, Jaclyn

2007-01-01

The purpose of this paper is to discuss the results of mission-based system trades when using a nuclear thermal propulsion (NTP) system for Solar System exploration. The results are based on comparing reactor designs that use a ceramic-metallic (CERMET), graphite matrix, graphite composite matrix, or carbide matrix fuel element designs. The composite graphite matrix and CERMET designs have been examined for providing power as well as propulsion. Approaches to the design of the NTP to be discussed will include an examination of graphite, composite, carbide, and CERMET core designs and the attributes of each in regards to performance and power generation capability. The focus is on NTP approaches based on tested fuel materials within a prismatic fuel form per the Argonne National Laboratory testing and the ROVER/NERVA program. NTP concepts have been examined for several years at Pratt & Whitney Rocketdyne for use as the primary propulsion for human missions beyond earth. Recently, an approach was taken to examine the design trades between specific NTP concepts; NERVA-based (UC)C-Graphite, (UC,ZrC)C-Composite, (U,Zr)C-Solid Carbide and UO2-W CERMET. Using Pratt & Whitney Rocketdyne's multidisciplinary design analysis capability, a detailed mission and vehicle model has been used to examine how several of these NTP designs impact a human Mars mission. Trends for the propulsion system mass as a function of power level (i.e. thrust size) for the graphite-carbide and CERMET designs were established and correlated against data created over the past forty years. These were used for the mission trade study. The resulting mission trades presented in this paper used a comprehensive modeling approach that captures the mission, vehicle subsystems, and NTP sizing.

Reference Models for Structural Technology Assessment and Weight Estimation

NASA Technical Reports Server (NTRS)

Cerro, Jeff; Martinovic, Zoran; Eldred, Lloyd

2005-01-01

Previously the Exploration Concepts Branch of NASA Langley Research Center has developed techniques for automating the preliminary design level of launch vehicle airframe structural analysis for purposes of enhancing historical regression based mass estimating relationships. This past work was useful and greatly reduced design time, however its application area was very narrow in terms of being able to handle a large variety in structural and vehicle general arrangement alternatives. Implementation of the analysis approach presented herein also incorporates some newly developed computer programs. Loft is a program developed to create analysis meshes and simultaneously define structural element design regions. A simple component defining ASCII file is read by Loft to begin the design process. HSLoad is a Visual Basic implementation of the HyperSizer Application Programming Interface, which automates the structural element design process. Details of these two programs and their use are explained in this paper. A feature which falls naturally out of the above analysis paradigm is the concept of "reference models". The flexibility of the FEA based JAVA processing procedures and associated process control classes coupled with the general utility of Loft and HSLoad make it possible to create generic program template files for analysis of components ranging from something as simple as a stiffened flat panel, to curved panels, fuselage and cryogenic tank components, flight control surfaces, wings, through full air and space vehicle general arrangements.

A Mixed-Fidelity Approach for Design of Low-Boom Supersonic Aircraft

NASA Technical Reports Server (NTRS)

Li, Wu; Shields, Elwood; Geiselhart, Karl A.

2010-01-01

This paper documents a mixed-fidelity approach for the design of low-boom supersonic aircraft as a viable approach for designing a practical low-boom supersonic configuration. A low-boom configuration that is based on low-fidelity analysis is used as the baseline. Tail lift is included to help tailor the aft portion of the ground signature. A comparison of low- and high-fidelity analysis results demonstrates the necessity of using computational fluid dynamics (CFD) analysis in a low-boom supersonic configuration design process. The fuselage shape is modified iteratively to obtain a configuration with a CFD equivalent-area distribution that matches a predetermined low-boom target distribution. The mixed-fidelity approach can easily refine the low-fidelity low-boom baseline into a low-boom configuration with the use of CFD equivalent-area analysis. The ground signature of the final configuration is calculated by using a state-of-the-art CFD-based boom analysis method that generates accurate midfield pressure distributions for propagation to the ground with ray tracing. The ground signature that is propagated from a midfield pressure distribution has a shaped ramp front, which is similar to the ground signature that is propagated from the CFD equivalent-area distribution. This result confirms the validity of the low-boom supersonic configuration design by matching a low-boom equivalent-area target, which is easier to accomplish than matching a low-boom midfield pressure target.

Design and Analysis Techniques for Concurrent Blackboard Systems. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Mcmanus, John William

1992-01-01

Blackboard systems are a natural progression of knowledge-based systems into a more powerful problem solving technique. They provide a way for several highly specialized knowledge sources to cooperate to solve large, complex problems. Blackboard systems incorporate the concepts developed by rule-based and expert systems programmers and include the ability to add conventionally coded knowledge sources. The small and specialized knowledge sources are easier to develop and test, and can be hosted on hardware specifically suited to the task that they are solving. The Formal Model for Blackboard Systems was developed to provide a consistent method for describing a blackboard system. A set of blackboard system design tools has been developed and validated for implementing systems that are expressed using the Formal Model. The tools are used to test and refine a proposed blackboard system design before the design is implemented. My research has shown that the level of independence and specialization of the knowledge sources directly affects the performance of blackboard systems. Using the design, simulation, and analysis tools, I developed a concurrent object-oriented blackboard system that is faster, more efficient, and more powerful than existing systems. The use of the design and analysis tools provided the highly specialized and independent knowledge sources required for my concurrent blackboard system to achieve its design goals.

Trench fast reactor design using the microcomputer

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

Rohach, A.F.; Sankoorikal, J.T.; Schmidt, R.R.

1987-01-01

This project is a study of alternative liquid-metal-cooled fast power reactor system concepts. Specifically, an unconventional primary system is being conceptually designed and evaluated. The project design is based primarily on microcomputer analysis through the use of computational modules. The reactor system concept is a long, narrow pool with a long, narrow reactor called a trench-type pool reactor in it. The reactor consists of five core-blanket modules in a line. Specific power is to be modest, permitting long fuel residence time. Two fuel cycles are currently being considered. The reactor design philosophy is that of the inherently safe concept. Thismore » requires transient analysis dependent on reactivity coefficients: prompt fuel, including Doppler and expansion, fuel expansion, sodium temperature and void, and core expansion. Conceptual reactor design is done on a microcomputer. A part of the trench reactor project is to develop a microcomputer-based system that can be used by the user for scoping studies and design. Current development includes the neutronics and fuel management aspects of the design. Thermal-hydraulic analysis and economics are currently being incorporated into the microcomputer system. The system is menu-driven including preparation of program input data and of output data for displays in graphics form.« less

Application of optimization techniques to vehicle design: A review

NASA Technical Reports Server (NTRS)

Prasad, B.; Magee, C. L.

1984-01-01

The work that has been done in the last decade or so in the application of optimization techniques to vehicle design is discussed. Much of the work reviewed deals with the design of body or suspension (chassis) components for reduced weight. Also reviewed are studies dealing with system optimization problems for improved functional performance, such as ride or handling. In reviewing the work on the use of optimization techniques, one notes the transition from the rare mention of the methods in the 70's to an increased effort in the early 80's. Efficient and convenient optimization and analysis tools still need to be developed so that they can be regularly applied in the early design stage of the vehicle development cycle to be most effective. Based on the reported applications, an attempt is made to assess the potential for automotive application of optimization techniques. The major issue involved remains the creation of quantifiable means of analysis to be used in vehicle design. The conventional process of vehicle design still contains much experience-based input because it has not yet proven possible to quantify all important constraints. This restraint on the part of the analysis will continue to be a major limiting factor in application of optimization to vehicle design.

Stochastic Simulation Tool for Aerospace Structural Analysis

NASA Technical Reports Server (NTRS)

Knight, Norman F.; Moore, David F.

2006-01-01

Stochastic simulation refers to incorporating the effects of design tolerances and uncertainties into the design analysis model and then determining their influence on the design. A high-level evaluation of one such stochastic simulation tool, the MSC.Robust Design tool by MSC.Software Corporation, has been conducted. This stochastic simulation tool provides structural analysts with a tool to interrogate their structural design based on their mathematical description of the design problem using finite element analysis methods. This tool leverages the analyst's prior investment in finite element model development of a particular design. The original finite element model is treated as the baseline structural analysis model for the stochastic simulations that are to be performed. A Monte Carlo approach is used by MSC.Robust Design to determine the effects of scatter in design input variables on response output parameters. The tool was not designed to provide a probabilistic assessment, but to assist engineers in understanding cause and effect. It is driven by a graphical-user interface and retains the engineer-in-the-loop strategy for design evaluation and improvement. The application problem for the evaluation is chosen to be a two-dimensional shell finite element model of a Space Shuttle wing leading-edge panel under re-entry aerodynamic loading. MSC.Robust Design adds value to the analysis effort by rapidly being able to identify design input variables whose variability causes the most influence in response output parameters.

Research and design of portable photoelectric rotary table data-acquisition and analysis system

NASA Astrophysics Data System (ADS)

Yang, Dawei; Yang, Xiufang; Han, Junfeng; Yan, Xiaoxu

2015-02-01

Photoelectric rotary table as the main test tracking measurement platform, widely use in shooting range and aerospace fields. In the range of photoelectric tracking measurement system, in order to meet the photoelectric testing instruments and equipment of laboratory and field application demand, research and design the portable photoelectric rotary table data acquisition and analysis system, and introduces the FPGA device based on Xilinx company Virtex-4 series and its peripheral module of the system hardware design, and the software design of host computer in VC++ 6.0 programming platform and MFC package based on class libraries. The data acquisition and analysis system for data acquisition, display and storage, commission control, analysis, laboratory wave playback, transmission and fault diagnosis, and other functions into an organic whole, has the advantages of small volume, can be embedded, high speed, portable, simple operation, etc. By photoelectric tracking turntable as experimental object, carries on the system software and hardware alignment, the experimental results show that the system can realize the data acquisition, analysis and processing of photoelectric tracking equipment and control of turntable debugging good, and measurement results are accurate, reliable and good maintainability and extensibility. The research design for advancing the photoelectric tracking measurement equipment debugging for diagnosis and condition monitoring and fault analysis as well as the standardization and normalization of the interface and improve the maintainability of equipment is of great significance, and has certain innovative and practical value.

New product development: A batik multifunctional chair

NASA Astrophysics Data System (ADS)

Indrawati, Sri; Sukmaningsih, Nias

2017-11-01

The biggest challenge facing by Batik industry in ASEAN Economic Community (AEC) era is the greater number of fashion competitors both domestically and internationally. Based on that condition, the development of new product variants by considering product performance and price is needed. This research was conducted to develop batik products with a new target market. Products that being developed is batik multifunctional chair using integrated value engineering and analytic hierarchy process methods. This research has been done in several stages, ie. Information stage, creative stage, value analysis and product prototyping. The results of this research shows that the batik multifunctional chair product criteria are aesthetic (29%), multifunctional (34%) and ergonomic (37%). There are three new product design alternatives that successfully being developed. Based on value analysis, the product design alternatives that have the highest value is alternative design 2, the value is 2,37. The production cost for this design is Rp. 500.000,-. Alternative design 2 specification are using Mahoni wood, Batik parang rusak pattern with natural coloring process, can be used as table and fit with customer's body anthropometry. Then a batik multifunctional chair prototype is developed based on the best alternative design.

Design of an electro-optic-polymer-based Mach-Zehnder modulator

NASA Astrophysics Data System (ADS)

Haugen, Chris J.; DeCorby, Ray G.; McMullin, James N.; Pulikkaseril, C.

2000-12-01

A novel structure for an electro-optic (e-o) polymer based Mach-Zehnder modulator is proposed and its anticipated device performance is detailed. The modulator is designed using commercially available materials and makes usc of wellcharacterized electrical and optical structures. The modulator is designed to be competitive with the pertrmance of LiNbO based modulators. The results of the analysis predict a bandwidth of 20 GHz, V of 8-10 V, optical insertion loss of S d13, and a contrast ratio of approximately 13 dB.

Towards Risk Based Design for NASA's Missions

NASA Technical Reports Server (NTRS)

Tumer, Irem Y.; Barrientos, Francesca; Meshkat, Leila

2004-01-01

This paper describes the concept of Risk Based Design in the context of NASA s low volume, high cost missions. The concept of accounting for risk in the design lifecycle has been discussed and proposed under several research topics, including reliability, risk analysis, optimization, uncertainty, decision-based design, and robust design. This work aims to identify and develop methods to enable and automate a means to characterize and optimize risk, and use risk as a tradeable resource to make robust and reliable decisions, in the context of the uncertain and ambiguous stage of early conceptual design. This paper first presents a survey of the related topics explored in the design research community as they relate to risk based design. Then, a summary of the topics from the NASA-led Risk Colloquium is presented, followed by current efforts within NASA to account for risk in early design. Finally, a list of "risk elements", identified for early-phase conceptual design at NASA, is presented. The purpose is to lay the foundation and develop a roadmap for future work and collaborations for research to eliminate and mitigate these risk elements in early phase design.

Numerical Analysis of Base Flowfield for a Four-Engine Clustered Nozzle Configuration

NASA Technical Reports Server (NTRS)

Wang, Ten-See

1995-01-01

Excessive base heating has been a problem for many launch vehicles. For certain designs such as the direct dump of turbine exhaust inside and at the lip of the nozzle, the potential burning of the turbine exhaust in the base region can be of great concern. Accurate prediction of the base environment at altitudes is therefore very important during the vehicle design phase. Otherwise, undesirable consequences may occur. In this study, the turbulent base flowfield of a cold flow experimental investigation for a four-engine clustered nozzle was numerically benchmarked using a pressure-based computational fluid dynamics (CFD) method. This is a necessary step before the benchmarking of hot flow and combustion flow tests can be considered. Since the medium was unheated air, reasonable prediction of the base pressure distribution at high altitude was the main goal. Several physical phenomena pertaining to the multiengine clustered nozzle base flow physics were deduced from the analysis.

Application of probabilistic analysis/design methods in space programs - The approaches, the status, and the needs

NASA Technical Reports Server (NTRS)

Ryan, Robert S.; Townsend, John S.

1993-01-01

The prospective improvement of probabilistic methods for space program analysis/design entails the further development of theories, codes, and tools which match specific areas of application, the drawing of lessons from previous uses of probability and statistics data bases, the enlargement of data bases (especially in the field of structural failures), and the education of engineers and managers on the advantages of these methods. An evaluation is presently made of the current limitations of probabilistic engineering methods. Recommendations are made for specific applications.

Design of integration-ready metasurface-based infrared absorbers

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

Ogando, Karim, E-mail: karim@cab.cnea.gov.ar; Pastoriza, Hernán

2015-07-28

We introduce an integration ready design of metamaterial infrared absorber, highly compatible with many kinds of fabrication processes. We present the results of an exhaustive experimental characterization, including an analysis of the effects of single meta-atom geometrical parameters and collective arrangement. We confront the results with the theoretical interpretations proposed in the literature. Based on the results, we develop a set of practical design rules for metamaterial absorbers in the infrared region.

F-4 Beryllium Rudders; A Precis of the Design, Fabrication, Ground and Flight Test Demonstrations

DTIC Science & Technology

1975-05-01

Wright-Patterson Air Force Base , Ohio 45433. AIR FORCE FLIGHT DYNAMICS LABORATORY AIR FORCE SYSTEMS COMMAND WRIGHT-PATTERSON AIR FORCE BASE , OHIO 45433...rudder. These sequential ground tests include: - A 50,000 cycle fatigue test of upper balance weight support structure. A static test to...Design Details 6. Design Analysis 7. Rudder Mass Balance 8, Rudder Moment of Inertia 9, Rudder Weight RUDDER FABRICATION AND ASSEMBLY 1. 2

Design criteria for payload workstation accommodations

NASA Technical Reports Server (NTRS)

Watters, H. H.; Stokes, J. W.

1975-01-01

Anticipated shuttle sortie payload man-system design criteria needs are investigated. Man-system interactions for the scientific disciplines are listed and the extent is assessed to which documented Skylab experience is expected to provide system design guidance for each of the identified interactions. Where the analysis revealed that the reduced Skylab data does not answer the anticipated needs candidate criteria, based on unreduced Skylab data, available prior research, original analysis, or related requirements derived from previous space programs, are provided.

Model-Based Systems Engineering With the Architecture Analysis and Design Language (AADL) Applied to NASA Mission Operations

NASA Technical Reports Server (NTRS)

Munoz Fernandez, Michela Miche

2014-01-01

The potential of Model Model Systems Engineering (MBSE) using the Architecture Analysis and Design Language (AADL) applied to space systems will be described. AADL modeling is applicable to real-time embedded systems- the types of systems NASA builds. A case study with the Juno mission to Jupiter showcases how this work would enable future missions to benefit from using these models throughout their life cycle from design to flight operations.

Internet-based distributed collaborative environment for engineering education and design

NASA Astrophysics Data System (ADS)

Sun, Qiuli

2001-07-01

This research investigates the use of the Internet for engineering education, design, and analysis through the presentation of a Virtual City environment. The main focus of this research was to provide an infrastructure for engineering education, test the concept of distributed collaborative design and analysis, develop and implement the Virtual City environment, and assess the environment's effectiveness in the real world. A three-tier architecture was adopted in the development of the prototype, which contains an online database server, a Web server as well as multi-user servers, and client browsers. The environment is composed of five components, a 3D virtual world, multiple Internet-based multimedia modules, an online database, a collaborative geometric modeling module, and a collaborative analysis module. The environment was designed using multiple Intenet-based technologies, such as Shockwave, Java, Java 3D, VRML, Perl, ASP, SQL, and a database. These various technologies together formed the basis of the environment and were programmed to communicate smoothly with each other. Three assessments were conducted over a period of three semesters. The Virtual City is open to the public at www.vcity.ou.edu. The online database was designed to manage the changeable data related to the environment. The virtual world was used to implement 3D visualization and tie the multimedia modules together. Students are allowed to build segments of the 3D virtual world upon completion of appropriate undergraduate courses in civil engineering. The end result is a complete virtual world that contains designs from all of their coursework and is viewable on the Internet. The environment is a content-rich educational system, which can be used to teach multiple engineering topics with the help of 3D visualization, animations, and simulations. The concept of collaborative design and analysis using the Internet was investigated and implemented. Geographically dispersed users can build the same geometric model simultaneously over the Internet and communicate with each other through a chat room. They can also conduct finite element analysis collaboratively on the same object over the Internet. They can mesh the same object, apply and edit the same boundary conditions and forces, obtain the same analysis results, and then discuss the results through the Internet.

Development of a Dynamically Configurable,Object-Oriented Framework for Distributed, Multi-modal Computational Aerospace Systems Simulation

NASA Technical Reports Server (NTRS)

Afjeh, Abdollah A.; Reed, John A.

2003-01-01

This research is aimed at developing a neiv and advanced simulation framework that will significantly improve the overall efficiency of aerospace systems design and development. This objective will be accomplished through an innovative integration of object-oriented and Web-based technologies ivith both new and proven simulation methodologies. The basic approach involves Ihree major areas of research: Aerospace system and component representation using a hierarchical object-oriented component model which enables the use of multimodels and enforces component interoperability. Collaborative software environment that streamlines the process of developing, sharing and integrating aerospace design and analysis models. . Development of a distributed infrastructure which enables Web-based exchange of models to simplify the collaborative design process, and to support computationally intensive aerospace design and analysis processes. Research for the first year dealt with the design of the basic architecture and supporting infrastructure, an initial implementation of that design, and a demonstration of its application to an example aircraft engine system simulation.

Participatory design of an integrated information system design to support public health nurses and nurse managers.

PubMed

Reeder, Blaine; Hills, Rebecca A; Turner, Anne M; Demiris, George

2014-01-01

The objectives of the study were to use persona-driven and scenario-based design methods to create a conceptual information system design to support public health nursing. We enrolled 19 participants from two local health departments to conduct an information needs assessment, create a conceptual design, and conduct a preliminary design validation. Interviews and thematic analysis were used to characterize information needs and solicit design recommendations from participants. Personas were constructed from participant background information, and scenario-based design was used to create a conceptual information system design. Two focus groups were conducted as a first iteration validation of information needs, personas, and scenarios. Eighty-nine information needs were identified. Two personas and 89 scenarios were created. Public health nurses and nurse managers confirmed the accuracy of information needs, personas, scenarios, and the perceived usefulness of proposed features of the conceptual design. Design artifacts were modified based on focus group results. Persona-driven design and scenario-based design are feasible methods to design for common work activities in different local health departments. Public health nurses and nurse managers should be engaged in the design of systems that support their work. © 2013 Wiley Periodicals, Inc.

Full-Carpet Design of a Low-Boom Demonstrator Concept

NASA Technical Reports Server (NTRS)

Ordaz, Irian; Wintzer, Mathias; Rallabhandi, Sriram K.

2015-01-01

The Cart3D adjoint-based design framework is used to mitigate the undesirable o -track sonic boom properties of a demonstrator concept designed for low-boom directly under the flight path. First, the requirements of a Cart3D design mesh are determined using a high-fidelity mesh adapted to minimize the discretization error of the CFD analysis. Low-boom equivalent area targets are then generated at the under-track and one off-track azimuthal position for the baseline configuration. The under-track target is generated using a trim- feasible low-boom target generation process, ensuring that the final design is not only low-boom, but also trimmed at the specified flight condition. The o -track equivalent area target is generated by minimizing the A-weighted loudness using an efficient adjoint-based approach. The configuration outer mold line is then parameterized and optimized to match the off-body pressure distributions prescribed by the low-boom targets. The numerical optimizer uses design gradients which are calculated using the Cart3D adjoint- based design capability. Optimization constraints are placed on the geometry to satisfy structural feasibility. The low-boom properties of the final design are verified using the adaptive meshing approach. This analysis quantifies the error associated with the CFD mesh that is used for design. Finally, an alternate mesh construction and target positioning approach offering greater computational efficiency is demonstrated and verified.

Geotechnical risk analysis user's guide

DOT National Transportation Integrated Search

1987-03-01

All geotechnical predictions involve uncertainties. These are accounted for additionally by conservative factors of safety. Risk based design, on the other hand, attempts to quantify uncertainties and to adjust design conservatism accordingly. Such m...

The design principles of edutainment system for autistic children with communication difficulties

NASA Astrophysics Data System (ADS)

Hussain, Azham; Abdullah, Adil; Husni, Husniza

2016-08-01

Approximately 50% of all individuals with Autism have difficulties in developing functional language owing to communication deterioration. Mobile devices with installed educational games help these individuals feel more comfortable and relaxed doing such activities. Although numerous mobile applications are available for individuals with Autism, they are difficult to use; particularly in terms of user-interface design. From the analysis of existing apps for autistic children, an app design principles are proposed based on interaction design (IxD), that would fulfil the users' requirements in a better manner. Five applications were involved in this analysis. The analysis identified fifteen suggestions for the design principles. These recommendations are offered by this paper towards designing and developing a prototype app for autistic children. This paper introduces an edutainment-system design principle formulated to help develop the communication skills of children with Autism-spectrum disorders.

Naturally-Emerging Technology-Based Leadership Roles in Three Independent Schools: A Social Network-Based Case Study Using Fuzzy Set Qualitative Comparative Analysis

ERIC Educational Resources Information Center

Velastegui, Pamela J.

2013-01-01

This hypothesis-generating case study investigates the naturally emerging roles of technology brokers and technology leaders in three independent schools in New York involving 92 school educators. A multiple and mixed method design utilizing Social Network Analysis (SNA) and fuzzy set Qualitative Comparative Analysis (FSQCA) involved gathering…

The Professoriate in the Field of Educational Administration: Insights from an Analysis of Journal Authors' Curricula Vitae

ERIC Educational Resources Information Center

Oplatka, Izhar

2010-01-01

Purpose: Based on a qualitative content analysis of 57 curricula vitae of authors who published their work in the major journals of the educational administration (EA) field, this paper seeks to display the career of EA authors and to suggest some epistemological implications for the field. Design/methodology/approach: The analysis is based on…

Integrated design, execution, and analysis of arrayed and pooled CRISPR genome-editing experiments.

PubMed

Canver, Matthew C; Haeussler, Maximilian; Bauer, Daniel E; Orkin, Stuart H; Sanjana, Neville E; Shalem, Ophir; Yuan, Guo-Cheng; Zhang, Feng; Concordet, Jean-Paul; Pinello, Luca

2018-05-01

CRISPR (clustered regularly interspaced short palindromic repeats) genome-editing experiments offer enormous potential for the evaluation of genomic loci using arrayed single guide RNAs (sgRNAs) or pooled sgRNA libraries. Numerous computational tools are available to help design sgRNAs with optimal on-target efficiency and minimal off-target potential. In addition, computational tools have been developed to analyze deep-sequencing data resulting from genome-editing experiments. However, these tools are typically developed in isolation and oftentimes are not readily translatable into laboratory-based experiments. Here, we present a protocol that describes in detail both the computational and benchtop implementation of an arrayed and/or pooled CRISPR genome-editing experiment. This protocol provides instructions for sgRNA design with CRISPOR (computational tool for the design, evaluation, and cloning of sgRNA sequences), experimental implementation, and analysis of the resulting high-throughput sequencing data with CRISPResso (computational tool for analysis of genome-editing outcomes from deep-sequencing data). This protocol allows for design and execution of arrayed and pooled CRISPR experiments in 4-5 weeks by non-experts, as well as computational data analysis that can be performed in 1-2 d by both computational and noncomputational biologists alike using web-based and/or command-line versions.

Neural networks for structural design - An integrated system implementation

NASA Technical Reports Server (NTRS)

Berke, Laszlo; Hafez, Wassim; Pao, Yoh-Han

1992-01-01

The development of powerful automated procedures to aid the creative designer is becoming increasingly critical for complex design tasks. In the work described here Artificial Neural Nets are applied to acquire structural analysis and optimization domain expertise. Based on initial instructions from the user an automated procedure generates random instances of structural analysis and/or optimization 'experiences' that cover a desired domain. It extracts training patterns from the created instances, constructs and trains an appropriate network architecture and checks the accuracy of net predictions. The final product is a trained neural net that can estimate analysis and/or optimization results instantaneously.

A wideband FMBEM for 2D acoustic design sensitivity analysis based on direct differentiation method

NASA Astrophysics Data System (ADS)

Chen, Leilei; Zheng, Changjun; Chen, Haibo

2013-09-01

This paper presents a wideband fast multipole boundary element method (FMBEM) for two dimensional acoustic design sensitivity analysis based on the direct differentiation method. The wideband fast multipole method (FMM) formed by combining the original FMM and the diagonal form FMM is used to accelerate the matrix-vector products in the boundary element analysis. The Burton-Miller formulation is used to overcome the fictitious frequency problem when using a single Helmholtz boundary integral equation for exterior boundary-value problems. The strongly singular and hypersingular integrals in the sensitivity equations can be evaluated explicitly and directly by using the piecewise constant discretization. The iterative solver GMRES is applied to accelerate the solution of the linear system of equations. A set of optimal parameters for the wideband FMBEM design sensitivity analysis are obtained by observing the performances of the wideband FMM algorithm in terms of computing time and memory usage. Numerical examples are presented to demonstrate the efficiency and validity of the proposed algorithm.

Sizing and Lifecycle Cost Analysis of an Ares V Composite Interstage

NASA Technical Reports Server (NTRS)

Mann, Troy; Smeltzer, Stan; Grenoble, Ray; Mason, Brian; Rosario, Sev; Fairbairn, Bob

2012-01-01

The Interstage Element of the Ares V launch vehicle was sized using a commercially available structural sizing software tool. Two different concepts were considered, a metallic design and a composite design. Both concepts were sized using similar levels of analysis fidelity and included the influence of design details on each concept. Additionally, the impact of the different manufacturing techniques and failure mechanisms for composite and metallic construction were considered. Significant details were included in analysis models of each concept, including penetrations for human access, joint connections, as well as secondary loading effects. The designs and results of the analysis were used to determine lifecycle cost estimates for the two Interstage designs. Lifecycle cost estimates were based on industry provided cost data for similar launch vehicle components. The results indicated that significant mass as well as cost savings are attainable for the chosen composite concept as compared with a metallic option.

Population Analysis: Communicating in Context

NASA Technical Reports Server (NTRS)

Rajulu, Sudhakar; Thaxton, Sherry

2008-01-01

Providing accommodation to a widely varying user population presents a challenge to engineers and designers. It is often even difficult to quantify who is accommodated and who is not accommodated by designs, especially for equipment with multiple critical anthropometric dimensions. An approach to communicating levels of accommodation referred to as population analysis applies existing human factors techniques in novel ways. This paper discusses the definition of population analysis as well as major applications and case studies. The major applications of population analysis consist of providing accommodation information for multivariate problems and enhancing the value of feedback from human-in-the-loop testing. The results of these analyses range from the provision of specific accommodation percentages of the user population to recommendations of design specifications based on quantitative data. Such feedback is invaluable to designers and results in the design of products that accommodate the intended user population.

Using phase II data for the analysis of phase III studies: An application in rare diseases.

PubMed

Wandel, Simon; Neuenschwander, Beat; Röver, Christian; Friede, Tim

2017-06-01

Clinical research and drug development in orphan diseases are challenging, since large-scale randomized studies are difficult to conduct. Formally synthesizing the evidence is therefore of great value, yet this is rarely done in the drug-approval process. Phase III designs that make better use of phase II data can facilitate drug development in orphan diseases. A Bayesian meta-analytic approach is used to inform the phase III study with phase II data. It is particularly attractive, since uncertainty of between-trial heterogeneity can be dealt with probabilistically, which is critical if the number of studies is small. Furthermore, it allows quantifying and discounting the phase II data through the predictive distribution relevant for phase III. A phase III design is proposed which uses the phase II data and considers approval based on a phase III interim analysis. The design is illustrated with a non-inferiority case study from a Food and Drug Administration approval in herpetic keratitis (an orphan disease). Design operating characteristics are compared to those of a traditional design, which ignores the phase II data. An analysis of the phase II data reveals good but insufficient evidence for non-inferiority, highlighting the need for a phase III study. For the phase III study supported by phase II data, the interim analysis is based on half of the patients. For this design, the meta-analytic interim results are conclusive and would justify approval. In contrast, based on the phase III data only, interim results are inconclusive and require further evidence. To accelerate drug development for orphan diseases, innovative study designs and appropriate methodology are needed. Taking advantage of randomized phase II data when analyzing phase III studies looks promising because the evidence from phase II supports informed decision-making. The implementation of the Bayesian design is straightforward with public software such as R.

Integrated analysis and design of thick composite structures for optimal passive damping characteristics

NASA Technical Reports Server (NTRS)

Saravanos, D. A.

1993-01-01

The development of novel composite mechanics for the analysis of damping in composite laminates and structures and the more significant results of this effort are summarized. Laminate mechanics based on piecewise continuous in-plane displacement fields are described that can represent both intralaminar stresses and interlaminar shear stresses and the associated effects on the stiffness and damping characteristics of a composite laminate. Among other features, the mechanics can accurately model the static and damped dynamic response of either thin or thick composite laminates, as well as, specialty laminates with embedded compliant damping layers. The discrete laminate damping theory is further incorporated into structural analysis methods. In this context, an exact semi-analytical method for the simulation of the damped dynamic response of composite plates was developed. A finite element based method and a specialty four-node plate element were also developed for the analysis of composite structures of variable shape and boundary conditions. Numerous evaluations and applications demonstrate the quality and superiority of the mechanics in predicting the damped dynamic characteristics of composite structures. Finally, additional development was focused on the development of optimal tailoring methods for the design of thick composite structures based on the developed analytical capability. Applications on composite plates illustrated the influence of composite mechanics in the optimal design of composites and the potential for significant deviations in the resultant designs when more simplified (classical) laminate theories are used.

Probability-Based Design Criteria of the ASCE 7 Tsunami Loads and Effects Provisions (Invited)

NASA Astrophysics Data System (ADS)

Chock, G.

2013-12-01

Mitigation of tsunami risk requires a combination of emergency preparedness for evacuation in addition to providing structural resilience of critical facilities, infrastructure, and key resources necessary for immediate response and economic and social recovery. Critical facilities would include emergency response, medical, tsunami refuges and shelters, ports and harbors, lifelines, transportation, telecommunications, power, financial institutions, and major industrial/commercial facilities. The Tsunami Loads and Effects Subcommittee of the ASCE/SEI 7 Standards Committee is developing a proposed new Chapter 6 - Tsunami Loads and Effects for the 2016 edition of the ASCE 7 Standard. ASCE 7 provides the minimum design loads and requirements for structures subject to building codes such as the International Building Code utilized in the USA. In this paper we will provide a review emphasizing the intent of these new code provisions and explain the design methodology. The ASCE 7 provisions for Tsunami Loads and Effects enables a set of analysis and design methodologies that are consistent with performance-based engineering based on probabilistic criteria. . The ASCE 7 Tsunami Loads and Effects chapter will be initially applicable only to the states of Alaska, Washington, Oregon, California, and Hawaii. Ground shaking effects and subsidence from a preceding local offshore Maximum Considered Earthquake will also be considered prior to tsunami arrival for Alaska and states in the Pacific Northwest regions governed by nearby offshore subduction earthquakes. For national tsunami design provisions to achieve a consistent reliability standard of structural performance for community resilience, a new generation of tsunami inundation hazard maps for design is required. The lesson of recent tsunami is that historical records alone do not provide a sufficient measure of the potential heights of future tsunamis. Engineering design must consider the occurrence of events greater than scenarios in the historical record, and should properly be based on the underlying seismicity of subduction zones. Therefore, Probabilistic Tsunami Hazard Analysis (PTHA) consistent with source seismicity must be performed in addition to consideration of historical event scenarios. A method of Probabilistic Tsunami Hazard Analysis has been established that is generally consistent with Probabilistic Seismic Hazard Analysis in the treatment of uncertainty. These new tsunami design zone maps will define the coastal zones where structures of greater importance would be designed for tsunami resistance and community resilience. Structural member acceptability criteria will be based on performance objectives for a 2,500-year Maximum Considered Tsunami. The approach developed by the ASCE Tsunami Loads and Effects Subcommittee of the ASCE 7 Standard would result in the first national unification of tsunami hazard criteria for design codes reflecting the modern approach of Performance-Based Engineering.

Efficiency enhancement of optimized Latin hypercube sampling strategies: Application to Monte Carlo uncertainty analysis and meta-modeling

NASA Astrophysics Data System (ADS)

Rajabi, Mohammad Mahdi; Ataie-Ashtiani, Behzad; Janssen, Hans

2015-02-01

The majority of literature regarding optimized Latin hypercube sampling (OLHS) is devoted to increasing the efficiency of these sampling strategies through the development of new algorithms based on the combination of innovative space-filling criteria and specialized optimization schemes. However, little attention has been given to the impact of the initial design that is fed into the optimization algorithm, on the efficiency of OLHS strategies. Previous studies, as well as codes developed for OLHS, have relied on one of the following two approaches for the selection of the initial design in OLHS: (1) the use of random points in the hypercube intervals (random LHS), and (2) the use of midpoints in the hypercube intervals (midpoint LHS). Both approaches have been extensively used, but no attempt has been previously made to compare the efficiency and robustness of their resulting sample designs. In this study we compare the two approaches and show that the space-filling characteristics of OLHS designs are sensitive to the initial design that is fed into the optimization algorithm. It is also illustrated that the space-filling characteristics of OLHS designs based on midpoint LHS are significantly better those based on random LHS. The two approaches are compared by incorporating their resulting sample designs in Monte Carlo simulation (MCS) for uncertainty propagation analysis, and then, by employing the sample designs in the selection of the training set for constructing non-intrusive polynomial chaos expansion (NIPCE) meta-models which subsequently replace the original full model in MCSs. The analysis is based on two case studies involving numerical simulation of density dependent flow and solute transport in porous media within the context of seawater intrusion in coastal aquifers. We show that the use of midpoint LHS as the initial design increases the efficiency and robustness of the resulting MCSs and NIPCE meta-models. The study also illustrates that this relative improvement decreases with increasing number of sample points and input parameter dimensions. Since the computational time and efforts for generating the sample designs in the two approaches are identical, the use of midpoint LHS as the initial design in OLHS is thus recommended.

3-D CFD Simulation and Validation of Oxygen-Rich Hydrocarbon Combustion in a Gas-Centered Swirl Coaxial Injector using a Flamelet-Based Approach

NASA Technical Reports Server (NTRS)

Richardson, Brian; Kenny, Jeremy

2015-01-01

Injector design is a critical part of the development of a rocket Thrust Chamber Assembly (TCA). Proper detailed injector design can maximize propulsion efficiency while minimizing the potential for failures in the combustion chamber. Traditional design and analysis methods for hydrocarbon-fuel injector elements are based heavily on empirical data and models developed from heritage hardware tests. Using this limited set of data produces challenges when trying to design a new propulsion system where the operating conditions may greatly differ from heritage applications. Time-accurate, Three-Dimensional (3-D) Computational Fluid Dynamics (CFD) modeling of combusting flows inside of injectors has long been a goal of the fluid analysis group at Marshall Space Flight Center (MSFC) and the larger CFD modeling community. CFD simulation can provide insight into the design and function of an injector that cannot be obtained easily through testing or empirical comparisons to existing hardware. However, the traditional finite-rate chemistry modeling approach utilized to simulate combusting flows for complex fuels, such as Rocket Propellant-2 (RP-2), is prohibitively expensive and time consuming even with a large amount of computational resources. MSFC has been working, in partnership with Streamline Numerics, Inc., to develop a computationally efficient, flamelet-based approach for modeling complex combusting flow applications. In this work, a flamelet modeling approach is used to simulate time-accurate, 3-D, combusting flow inside a single Gas Centered Swirl Coaxial (GCSC) injector using the flow solver, Loci-STREAM. CFD simulations were performed for several different injector geometries. Results of the CFD analysis helped guide the design of the injector from an initial concept to a tested prototype. The results of the CFD analysis are compared to data gathered from several hot-fire, single element injector tests performed in the Air Force Research Lab EC-1 test facility located at Edwards Air Force Base.

Conceptual design studies for surface infrastructure

NASA Technical Reports Server (NTRS)

Bufkin, Ann L.; Jones, William R., II

1986-01-01

The utimate design of a manned Mars base will be the result of considerable engineering analysis and many trade studies to optimize the configuration. Many options and scenarios are available and all need to be considered at this time. Initial base elements, two base configuration concepts, internal space architectural concerns, and two base set-up scenarios are discussed. There are many variables as well as many unknowns to be reckoned with before people set foot on the red planet.

The environment power system analysis tool development program

NASA Technical Reports Server (NTRS)

Jongeward, Gary A.; Kuharski, Robert A.; Kennedy, Eric M.; Stevens, N. John; Putnam, Rand M.; Roche, James C.; Wilcox, Katherine G.

1990-01-01

The Environment Power System Analysis Tool (EPSAT) is being developed to provide space power system design engineers with an analysis tool for determining system performance of power systems in both naturally occurring and self-induced environments. The program is producing an easy to use computer aided engineering (CAE) tool general enough to provide a vehicle for technology transfer from space scientists and engineers to power system design engineers. The results of the project after two years of a three year development program are given. The EPSAT approach separates the CAE tool into three distinct functional units: a modern user interface to present information, a data dictionary interpreter to coordinate analysis; and a data base for storing system designs and results of analysis.

An Approach to Risk-Based Design Incorporating Damage Tolerance Analyses

NASA Technical Reports Server (NTRS)

Knight, Norman F., Jr.; Glaessgen, Edward H.; Sleight, David W.

2002-01-01

Incorporating risk-based design as an integral part of spacecraft development is becoming more and more common. Assessment of uncertainties associated with design parameters and environmental aspects such as loading provides increased knowledge of the design and its performance. Results of such studies can contribute to mitigating risk through a system-level assessment. Understanding the risk of an event occurring, the probability of its occurrence, and the consequences of its occurrence can lead to robust, reliable designs. This paper describes an approach to risk-based structural design incorporating damage-tolerance analysis. The application of this approach to a candidate Earth-entry vehicle is described. The emphasis of the paper is on describing an approach for establishing damage-tolerant structural response inputs to a system-level probabilistic risk assessment.

Enhanced terahertz imaging system performance analysis and design tool for concealed weapon identification

NASA Astrophysics Data System (ADS)

Murrill, Steven R.; Franck, Charmaine C.; Espinola, Richard L.; Petkie, Douglas T.; De Lucia, Frank C.; Jacobs, Eddie L.

2011-11-01

The U.S. Army Research Laboratory (ARL) and the U.S. Army Night Vision and Electronic Sensors Directorate (NVESD) have developed a terahertz-band imaging system performance model/tool for detection and identification of concealed weaponry. The details of the MATLAB-based model which accounts for the effects of all critical sensor and display components, and for the effects of atmospheric attenuation, concealment material attenuation, and active illumination, were reported on at the 2005 SPIE Europe Security & Defence Symposium (Brugge). An advanced version of the base model that accounts for both the dramatic impact that target and background orientation can have on target observability as related to specular and Lambertian reflections captured by an active-illumination-based imaging system, and for the impact of target and background thermal emission, was reported on at the 2007 SPIE Defense and Security Symposium (Orlando). This paper will provide a comprehensive review of an enhanced, user-friendly, Windows-executable, terahertz-band imaging system performance analysis and design tool that now includes additional features such as a MODTRAN-based atmospheric attenuation calculator and advanced system architecture configuration inputs that allow for straightforward performance analysis of active or passive systems based on scanning (single- or line-array detector element(s)) or staring (focal-plane-array detector elements) imaging architectures. This newly enhanced THz imaging system design tool is an extension of the advanced THz imaging system performance model that was developed under the Defense Advanced Research Project Agency's (DARPA) Terahertz Imaging Focal-Plane Technology (TIFT) program. This paper will also provide example system component (active-illumination source and detector) trade-study analyses using the new features of this user-friendly THz imaging system performance analysis and design tool.

The importance of operations, risk, and cost assessment to space transfer systems design

NASA Technical Reports Server (NTRS)

Ball, J. M.; Komerska, R. J.; Rowell, L. F.

1992-01-01

This paper examines several methodologies which contribute to comprehensive subsystem cost estimation. The example of a space-based lunar space transfer vehicle (STV) design is used to illustrate how including both primary and secondary factors into cost affects the decision of whether to use aerobraking or propulsion for earth orbit capture upon lunar return. The expected dominant cost factor in this decision is earth-to-orbit launch cost driven by STV mass. However, to quantify other significant cost factors, this cost comparison included a risk analysis to identify development and testing costs, a Taguchi design of experiments to determine a minimum mass aerobrake design, and a detailed operations analysis. As a result, the predicted cost advantage of aerobraking, while still positive, was subsequently reduced by about 30 percent compared to the simpler mass-based cost estimates.

The design guidelines of mobile augmented reality for tourism in Malaysia

NASA Astrophysics Data System (ADS)

Shukri, Saidatul A'isyah Ahmad; Arshad, Haslina; Abidin, Rimaniza Zainal

2017-10-01

Recent data shows that one in every five people in the world owns a Smartphone and spends most of their time on the phone using apps. Visitors prefer this type of portable, convenient, practical and simple technology when travelling, especially geo location-enabled applications such as the GPS. The aim of this paper is to develop design guidelines for Mobile Augmented Reality (MAR) for tourism. From the analysis of existing design guidelines of Mobile Augmented Reality (MAR) for tourism, an application design guidelines are proposed based on Human-computer interaction principle and usability design that would fulfils the user's requirement in a better way. Six design principles were examined in this analysis. The analysis identified eleven suggestions for design principles. These recommendations are offered towards designing principles and developing prototype app for tourist in Malaysia. This paper identifies design principles to reduce cognitive overhead of tourist, learn ability and suitable context for providing content whiles their travel in Malaysia.

PARTIAL RESTRAINING FORCE INTRODUCTION METHOD FOR DESIGNING CONSTRUCTION COUNTERMESURE ON ΔB METHOD

NASA Astrophysics Data System (ADS)

Nishiyama, Taku; Imanishi, Hajime; Chiba, Noriyuki; Ito, Takao

Landslide or slope failure is a three-dimensional movement phenomenon, thus a three-dimensional treatment makes it easier to understand stability. The ΔB method (simplified three-dimensional slope stability analysis method) is based on the limit equilibrium method and equals to an approximate three-dimensional slope stability analysis that extends two-dimensional cross-section stability analysis results to assess stability. This analysis can be conducted using conventional spreadsheets or two-dimensional slope stability computational software. This paper describes the concept of the partial restraining force in-troduction method for designing construction countermeasures using the distribution of the restraining force found along survey lines, which is based on the distribution of survey line safety factors derived from the above-stated analysis. This paper also presents the transverse distributive method of restraining force used for planning ground stabilizing on the basis of the example analysis.

Issues in developing valid assessments of speech pathology students' performance in the workplace.

PubMed

McAllister, Sue; Lincoln, Michelle; Ferguson, Alison; McAllister, Lindy

2010-01-01

Workplace-based learning is a critical component of professional preparation in speech pathology. A validated assessment of this learning is seen to be 'the gold standard', but it is difficult to develop because of design and validation issues. These issues include the role and nature of judgement in assessment, challenges in measuring quality, and the relationship between assessment and learning. Valid assessment of workplace-based performance needs to capture the development of competence over time and account for both occupation specific and generic competencies. This paper reviews important conceptual issues in the design of valid and reliable workplace-based assessments of competence including assessment content, process, impact on learning, measurement issues, and validation strategies. It then goes on to share what has been learned about quality assessment and validation of a workplace-based performance assessment using competency-based ratings. The outcomes of a four-year national development and validation of an assessment tool are described. A literature review of issues in conceptualizing, designing, and validating workplace-based assessments was conducted. Key factors to consider in the design of a new tool were identified and built into the cycle of design, trialling, and data analysis in the validation stages of the development process. This paper provides an accessible overview of factors to consider in the design and validation of workplace-based assessment tools. It presents strategies used in the development and national validation of a tool COMPASS, used in an every speech pathology programme in Australia, New Zealand, and Singapore. The paper also describes Rasch analysis, a model-based statistical approach which is useful for establishing validity and reliability of assessment tools. Through careful attention to conceptual and design issues in the development and trialling of workplace-based assessments, it has been possible to develop the world's first valid and reliable national assessment tool for the assessment of performance in speech pathology.

EEG Based Analysis of Cognitive Load Enhance Instructional Analysis

ERIC Educational Resources Information Center

Dan, Alex; Reiner, Miriam

2017-01-01

One of the recommended approaches in instructional design methods is to optimize the value of working memory capacity and avoid cognitive overload. Educational neuroscience offers novel processes and methodologies to analyze cognitive load based on physiological measures. Observing psychophysiological changes when they occur in response to the…

Utilizing Problem-Based Learning in Qualitative Analysis Lab Experiments

ERIC Educational Resources Information Center

Hicks, Randall W.; Bevsek, Holly M.

2012-01-01

A series of qualitative analysis (QA) laboratory experiments utilizing a problem-based learning (PBL) module has been designed and implemented. The module guided students through the experiments under the guise of cleaning up a potentially contaminated water site as employees of an environmental chemistry laboratory. The main goal was the…

Decision Support System Requirements Definition for Human Extravehicular Activity Based on Cognitive Work Analysis

PubMed Central

Miller, Matthew James; McGuire, Kerry M.; Feigh, Karen M.

2016-01-01

The design and adoption of decision support systems within complex work domains is a challenge for cognitive systems engineering (CSE) practitioners, particularly at the onset of project development. This article presents an example of applying CSE techniques to derive design requirements compatible with traditional systems engineering to guide decision support system development. Specifically, it demonstrates the requirements derivation process based on cognitive work analysis for a subset of human spaceflight operations known as extravehicular activity. The results are presented in two phases. First, a work domain analysis revealed a comprehensive set of work functions and constraints that exist in the extravehicular activity work domain. Second, a control task analysis was performed on a subset of the work functions identified by the work domain analysis to articulate the translation of subject matter states of knowledge to high-level decision support system requirements. This work emphasizes an incremental requirements specification process as a critical component of CSE analyses to better situate CSE perspectives within the early phases of traditional systems engineering design. PMID:28491008

Decision Support System Requirements Definition for Human Extravehicular Activity Based on Cognitive Work Analysis.

PubMed

Miller, Matthew James; McGuire, Kerry M; Feigh, Karen M

2017-06-01

The design and adoption of decision support systems within complex work domains is a challenge for cognitive systems engineering (CSE) practitioners, particularly at the onset of project development. This article presents an example of applying CSE techniques to derive design requirements compatible with traditional systems engineering to guide decision support system development. Specifically, it demonstrates the requirements derivation process based on cognitive work analysis for a subset of human spaceflight operations known as extravehicular activity . The results are presented in two phases. First, a work domain analysis revealed a comprehensive set of work functions and constraints that exist in the extravehicular activity work domain. Second, a control task analysis was performed on a subset of the work functions identified by the work domain analysis to articulate the translation of subject matter states of knowledge to high-level decision support system requirements. This work emphasizes an incremental requirements specification process as a critical component of CSE analyses to better situate CSE perspectives within the early phases of traditional systems engineering design.

Anti-inflammatory drugs and prediction of new structures by comparative analysis.

PubMed

Bartzatt, Ronald

2012-01-01

Nonsteroidal anti-inflammatory drugs (NSAIDs) are a group of agents important for their analgesic, anti-inflammatory, and antipyretic properties. This study presents several approaches to predict and elucidate new molecular structures of NSAIDs based on 36 known and proven anti-inflammatory compounds. Based on 36 known NSAIDs the mean value of Log P is found to be 3.338 (standard deviation= 1.237), mean value of polar surface area is 63.176 Angstroms2 (standard deviation = 20.951 A2), and the mean value of molecular weight is 292.665 (standard deviation = 55.627). Nine molecular properties are determined for these 36 NSAID agents, including Log P, number of -OH and -NHn, violations of Rule of 5, number of rotatable bonds, and number of oxygens and nitrogens. Statistical analysis of these nine molecular properties provides numerical parameters to conform to in the design of novel NSAID drug candidates. Multiple regression analysis is accomplished using these properties of 36 agents followed with examples of predicted molecular weight based on minimum and maximum property values. Hierarchical cluster analysis indicated that licofelone, tolfenamic acid, meclofenamic acid, droxicam, and aspirin are substantially distinct from all remaining NSAIDs. Analysis of similarity (ANOSIM) produced R = 0.4947, which indicates low to moderate level of dissimilarity between these 36 NSAIDs. Non-hierarchical K-means cluster analysis separated the 36 NSAIDs into four groups having members of greatest similarity. Likewise, discriminant analysis divided the 36 agents into two groups indicating the greatest level of distinction (discrimination) based on nine properties. These two multivariate methods together provide investigators a means to compare and elucidate novel drug designs to 36 proven compounds and ascertain to which of those are most analogous in pharmacodynamics. In addition, artificial neural network modeling is demonstrated as an approach to predict numerous molecular properties of new drug designs that is based on neural training from 36 proven NSAIDs. Comprehensive and effective approaches are presented in this study for the design of new NSAID type agents which are so very important for inhibition of COX-2 and COX-1 isoenzymes.

Orion Orbit Control Design and Analysis

NASA Technical Reports Server (NTRS)

Jackson, Mark; Gonzalez, Rodolfo; Sims, Christopher

2007-01-01

The analysis of candidate thruster configurations for the Crew Exploration Vehicle (CEV) is presented. Six candidate configurations were considered for the prime contractor baseline design. The analysis included analytical assessments of control authority, control precision, efficiency and robustness, as well as simulation assessments of control performance. The principles used in the analytic assessments of controllability, robustness and fuel performance are covered and results provided for the configurations assessed. Simulation analysis was conducted using a pulse width modulated, 6 DOF reaction system control law with a simplex-based thruster selection algorithm. Control laws were automatically derived from hardware configuration parameters including thruster locations, directions, magnitude and specific impulse, as well as vehicle mass properties. This parameterized controller allowed rapid assessment of multiple candidate layouts. Simulation results are presented for final phase rendezvous and docking, as well as low lunar orbit attitude hold. Finally, on-going analysis to consider alternate Service Module designs and to assess the pilot-ability of the baseline design are discussed to provide a status of orbit control design work to date.

Safety Guided Design Based on Stamp/STPA for Manned Vehicle in Concept Design Phase

NASA Astrophysics Data System (ADS)

Ujiie, Ryo; Katahira, Masafumi; Miyamoto, Yuko; Umeda, Hiroki; Leveson, Nancy; Hoshino, Nobuyuki

2013-09-01

In manned vehicles, such as the Soyuz and the Space Shuttle, the crew and computer system cooperate to succeed in returning to the earth. While computers increase the functionality of system, they also increase the complexity of the interaction between the controllers (human and computer) and the target dynamics. In some cases, the complexity can produce a serious accident. To prevent such losses, traditional hazard analysis such as FTA has been applied to system development, however it can be used after creating a detailed system because it focuses on detailed component failures. As a result, it's more difficult to eliminate hazard cause early in the process when it is most feasible.STAMP/STPA is a new hazard analysis that can be applied from the early development phase, with the analysis being refined as more detailed decisions are made. In essence, the analysis and design decisions are intertwined and go hand-in-hand. We have applied STAMP/STPA to a concept design of a new JAXA manned vehicle and tried safety guided design of the vehicle. As a result of this trial, it has been shown that STAMP/STPA can be accepted easily by system engineers and the design has been made more sophisticated from a safety viewpoint. The result also shows that the consequences of human errors on system safety can be analysed in the early development phase and the system designed to prevent them. Finally, the paper will discuss an effective way to harmonize this safety guided design approach with system engineering process based on the result of this experience in this project.

Application of discriminant analysis-based model for prediction of risk of low back disorders due to workplace design in industrial jobs.

PubMed

Ganga, G M D; Esposto, K F; Braatz, D

2012-01-01

The occupational exposure limits of different risk factors for development of low back disorders (LBDs) have not yet been established. One of the main problems in setting such guidelines is the limited understanding of how different risk factors for LBDs interact in causing injury, since the nature and mechanism of these disorders are relatively unknown phenomena. Industrial ergonomists' role becomes further complicated because the potential risk factors that may contribute towards the onset of LBDs interact in a complex manner, which makes it difficult to discriminate in detail among the jobs that place workers at high or low risk of LBDs. The purpose of this paper was to develop a comparative study between predictions based on the neural network-based model proposed by Zurada, Karwowski & Marras (1997) and a linear discriminant analysis model, for making predictions about industrial jobs according to their potential risk of low back disorders due to workplace design. The results obtained through applying the discriminant analysis-based model proved that it is as effective as the neural network-based model. Moreover, the discriminant analysis-based model proved to be more advantageous regarding cost and time savings for future data gathering.

META II Complex Systems Design and Analysis (CODA)

DTIC Science & Technology

2011-08-01

37  3.8.7  Variables, Parameters and Constraints ............................................................. 37  3.8.8  Objective...18  Figure 7: Inputs, States, Outputs and Parameters of System Requirements Specifications ......... 19...Design Rule Based on Device Parameter ....................................................... 57  Figure 35: AEE Device Design Rules (excerpt

A Framework for Creating a Function-based Design Tool for Failure Mode Identification

NASA Technical Reports Server (NTRS)

Arunajadai, Srikesh G.; Stone, Robert B.; Tumer, Irem Y.; Clancy, Daniel (Technical Monitor)

2002-01-01

Knowledge of potential failure modes during design is critical for prevention of failures. Currently industries use procedures such as Failure Modes and Effects Analysis (FMEA), Fault Tree analysis, or Failure Modes, Effects and Criticality analysis (FMECA), as well as knowledge and experience, to determine potential failure modes. When new products are being developed there is often a lack of sufficient knowledge of potential failure mode and/or a lack of sufficient experience to identify all failure modes. This gives rise to a situation in which engineers are unable to extract maximum benefits from the above procedures. This work describes a function-based failure identification methodology, which would act as a storehouse of information and experience, providing useful information about the potential failure modes for the design under consideration, as well as enhancing the usefulness of procedures like FMEA. As an example, the method is applied to fifteen products and the benefits are illustrated.

Conjoint Analysis for New Service Development on Electricity Distribution in Indonesia

NASA Astrophysics Data System (ADS)

Widaningrum, D. L.; Chynthia; Astuti, L. D.; Seran, M. A. B.

2017-07-01

Many cases of illegal use of electricity in Indonesia is still rampant, especially for activities where the power source is not available, such as in the location of street vendors. It is not only detrimental to the state, but also harm the perpetrators of theft of electricity and the surrounding communities. The purpose of this study is to create New Service Development (NSD) to provide a new electricity source for street vendors' activity based on their preferences. The methods applied in NSD is Conjoint Analysis, Cluster Analysis, Quality Function Deployment (QFD), Service Blueprint, Process Flow Diagrams and Quality Control Plan. The results of this study are the attributes and their importance in the new electricity’s service based on street vendors’ preferences as customers, customer segmentation, service design for new service, designing technical response, designing operational procedures, the quality control plan of any existing operational procedures.

Logic Design Pathology and Space Flight Electronics

NASA Technical Reports Server (NTRS)

Katz, Richard; Barto, Rod L.; Erickson, K.

1997-01-01

Logic design errors have been observed in space flight missions and the final stages of ground test. The technologies used by designers and their design/analysis methodologies will be analyzed. This will give insight to the root causes of the failures. These technologies include discrete integrated circuit based systems, systems based on field and mask programmable logic, and the use computer aided engineering (CAE) systems. State-of-the-art (SOTA) design tools and methodologies will be analyzed with respect to high-reliability spacecraft design and potential pitfalls are discussed. Case studies of faults from large expensive programs to "smaller, faster, cheaper" missions will be used to explore the fundamental reasons for logic design problems.

Multiphysics Engineering Analysis for an Integrated Design of ITER Diagnostic First Wall and Diagnostic Shield Module Design

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

Zhai, Y.; Loesser, G.; Smith, M.

ITER diagnostic first walls (DFWs) and diagnostic shield modules (DSMs) inside the port plugs (PPs) are designed to protect diagnostic instrument and components from a harsh plasma environment and provide structural support while allowing for diagnostic access to the plasma. The design of DFWs and DSMs are driven by 1) plasma radiation and nuclear heating during normal operation 2) electromagnetic loads during plasma events and associate component structural responses. A multi-physics engineering analysis protocol for the design has been established at Princeton Plasma Physics Laboratory and it was used for the design of ITER DFWs and DSMs. The analyses weremore » performed to address challenging design issues based on resultant stresses and deflections of the DFW-DSM-PP assembly for the main load cases. ITER Structural Design Criteria for In-Vessel Components (SDC-IC) required for design by analysis and three major issues driving the mechanical design of ITER DFWs are discussed. The general guidelines for the DSM design have been established as a result of design parametric studies.« less

Control of large flexible structures - An experiment on the NASA Mini-Mast facility

NASA Technical Reports Server (NTRS)

Hsieh, Chen; Kim, Jae H.; Liu, Ketao; Zhu, Guoming; Skelton, Robert E.

1991-01-01

The output variance constraint controller design procedure is integrated with model reduction by modal cost analysis. A procedure is given for tuning MIMO controller designs to find the maximal rms performance of the actual system. Controller designs based on a finite-element model of the system are compared with controller designs based on an identified model (obtained using the Q-Markov Cover algorithm). The identified model and the finite-element model led to similar closed-loop performance, when tested in the Mini-Mast facility at NASA Langley.

Evidence-Based Design and Research-Informed Design: What's the Difference? Conceptual Definitions and Comparative Analysis.

PubMed

Peavey, Erin; Vander Wyst, Kiley B

2017-10-01

This article provides critical examination and comparison of the conceptual meaning and underlying assumptions of the concepts evidence-based design (EBD) and research-informed design (RID) in order to facilitate practical use and theoretical development. In recent years, EBD has experienced broad adoption, yet it has been simultaneously critiqued for rigidity and misapplication. Many practitioners are gravitating to the term RID to describe their method of integrating knowledge into the design process. However, the term RID lacks a clear definition and the blurring of terms has the potential to weaken advances made integrating research into practice. Concept analysis methods from Walker and Avant were used to define the concepts for comparison. Conceptual definitions, process descriptions, examples (i.e., model cases), and methods of evaluation are offered for EBD and RID. Although EBD and RID share similarities in meaning, the two terms are distinct. When comparing evidence based (EB) and research informed, EB is a broad base of information types (evidence) that are narrowly applied (based), while the latter references a narrow slice of information (research) that is broadly applied (informed) to create an end product of design. Much of the confusion between the use of the concepts EBD and RID arises out of differing perspectives between the way practitioners and academics understand the underlying terms. The authors hope this article serves to generate thoughtful dialogue, which is essential to the development of a discipline, and look forward to the contribution of the readership.

Confronting Analytical Dilemmas for Understanding Complex Human Interactions in Design-Based Research from a Cultural-Historical Activity Theory (CHAT) Framework

ERIC Educational Resources Information Center

Yamagata-Lynch, Lisa C.

2007-01-01

Understanding human activity in real-world situations often involves complicated data collection, analysis, and presentation methods. This article discusses how Cultural-Historical Activity Theory (CHAT) can inform design-based research practices that focus on understanding activity in real-world situations. I provide a sample data set with…

Trust-Based Design of Human-Guided Algorithms

DTIC Science & Technology

2007-06-01

Management Interdepartmental Program in Operations Research 17 May, 2007 Approved by: Laura Major Forest The Charles Stark Draper Laboratory...2. Information Analysis: predicting based on data, integrating and managing information, augmenting human operator perception and cognition. 3...allocation of automation by designers and managers . How an operator decides between manual and automatic control of a system is a necessary

Supporting Collaborative Learning and Problem-Solving in a Constraint-Based CSCL Environment for UML Class Diagrams

ERIC Educational Resources Information Center

Baghaei, Nilufar; Mitrovic, Antonija; Irwin, Warwick

2007-01-01

We present COLLECT-UML, a constraint-based intelligent tutoring system (ITS) that teaches object-oriented analysis and design using Unified Modelling Language (UML). UML is easily the most popular object-oriented modelling technology in current practice. While teaching how to design UML class diagrams, COLLECT-UML also provides feedback on…

The Implementation and Evaluation of an Instructional Design Based on the Interdisciplinary Approach: Conscious Consumer Education

ERIC Educational Resources Information Center

Karakus, Memet; Uyar, Melis Yesilpinar

2018-01-01

The aim of this study was to implement and evaluate the instructional design prepared as consumer-oriented and based upon interdisciplinary curriculum. In this study, case study approach, which is one of the qualitative research patterns, was employed. Observations, interviews and document analysis were used to collect data. For analyzing the…

Opportunities and pitfalls in clinical proof-of-concept: principles and examples.

PubMed

Chen, Chao

2018-04-01

Clinical proof-of-concept trials crucially inform major resource deployment decisions. This paper discusses several mechanisms for enhancing their rigour and efficiency. The importance of careful consideration when using a surrogate endpoint is illustrated; situational effectiveness of run-in patient enrichment is explored; a versatile tool is introduced to ensure a strong pharmacological underpinning; the benefits of dose-titration are revealed by simulation; and the importance of adequately scheduled observations is shown. The general process of model-based trial design and analysis is described and several examples demonstrate the value in historical data, simulation-guided design, model-based analysis and trial adaptation informed by interim analysis. Copyright © 2018 Elsevier Ltd. All rights reserved.

Design and Analysis Tool for External-Compression Supersonic Inlets

NASA Technical Reports Server (NTRS)

Slater, John W.

2012-01-01

A computational tool named SUPIN has been developed to design and analyze external-compression supersonic inlets for aircraft at cruise speeds from Mach 1.6 to 2.0. The inlet types available include the axisymmetric outward-turning, two-dimensional single-duct, two-dimensional bifurcated-duct, and streamline-traced Busemann inlets. The aerodynamic performance is characterized by the flow rates, total pressure recovery, and drag. The inlet flowfield is divided into parts to provide a framework for the geometry and aerodynamic modeling and the parts are defined in terms of geometric factors. The low-fidelity aerodynamic analysis and design methods are based on analytic, empirical, and numerical methods which provide for quick analysis. SUPIN provides inlet geometry in the form of coordinates and surface grids useable by grid generation methods for higher-fidelity computational fluid dynamics (CFD) analysis. SUPIN is demonstrated through a series of design studies and CFD analyses were performed to verify some of the analysis results.

Failure Mode Identification Through Clustering Analysis

NASA Technical Reports Server (NTRS)

Arunajadai, Srikesh G.; Stone, Robert B.; Tumer, Irem Y.; Clancy, Daniel (Technical Monitor)

2002-01-01

Research has shown that nearly 80% of the costs and problems are created in product development and that cost and quality are essentially designed into products in the conceptual stage. Currently, failure identification procedures (such as FMEA (Failure Modes and Effects Analysis), FMECA (Failure Modes, Effects and Criticality Analysis) and FTA (Fault Tree Analysis)) and design of experiments are being used for quality control and for the detection of potential failure modes during the detail design stage or post-product launch. Though all of these methods have their own advantages, they do not give information as to what are the predominant failures that a designer should focus on while designing a product. This work uses a functional approach to identify failure modes, which hypothesizes that similarities exist between different failure modes based on the functionality of the product/component. In this paper, a statistical clustering procedure is proposed to retrieve information on the set of predominant failures that a function experiences. The various stages of the methodology are illustrated using a hypothetical design example.

Constellation Ground Systems Launch Availability Analysis: Enhancing Highly Reliable Launch Systems Design

NASA Technical Reports Server (NTRS)

Gernand, Jeffrey L.; Gillespie, Amanda M.; Monaghan, Mark W.; Cummings, Nicholas H.

2010-01-01

Success of the Constellation Program's lunar architecture requires successfully launching two vehicles, Ares I/Orion and Ares V/Altair, in a very limited time period. The reliability and maintainability of flight vehicles and ground systems must deliver a high probability of successfully launching the second vehicle in order to avoid wasting the on-orbit asset launched by the first vehicle. The Ground Operations Project determined which ground subsystems had the potential to affect the probability of the second launch and allocated quantitative availability requirements to these subsystems. The Ground Operations Project also developed a methodology to estimate subsystem reliability, availability and maintainability to ensure that ground subsystems complied with allocated launch availability and maintainability requirements. The verification analysis developed quantitative estimates of subsystem availability based on design documentation; testing results, and other information. Where appropriate, actual performance history was used for legacy subsystems or comparative components that will support Constellation. The results of the verification analysis will be used to verify compliance with requirements and to highlight design or performance shortcomings for further decision-making. This case study will discuss the subsystem requirements allocation process, describe the ground systems methodology for completing quantitative reliability, availability and maintainability analysis, and present findings and observation based on analysis leading to the Ground Systems Preliminary Design Review milestone.

A novel integrated framework and improved methodology of computer-aided drug design.

PubMed

Chen, Calvin Yu-Chian

2013-01-01

Computer-aided drug design (CADD) is a critical initiating step of drug development, but a single model capable of covering all designing aspects remains to be elucidated. Hence, we developed a drug design modeling framework that integrates multiple approaches, including machine learning based quantitative structure-activity relationship (QSAR) analysis, 3D-QSAR, Bayesian network, pharmacophore modeling, and structure-based docking algorithm. Restrictions for each model were defined for improved individual and overall accuracy. An integration method was applied to join the results from each model to minimize bias and errors. In addition, the integrated model adopts both static and dynamic analysis to validate the intermolecular stabilities of the receptor-ligand conformation. The proposed protocol was applied to identifying HER2 inhibitors from traditional Chinese medicine (TCM) as an example for validating our new protocol. Eight potent leads were identified from six TCM sources. A joint validation system comprised of comparative molecular field analysis, comparative molecular similarity indices analysis, and molecular dynamics simulation further characterized the candidates into three potential binding conformations and validated the binding stability of each protein-ligand complex. The ligand pathway was also performed to predict the ligand "in" and "exit" from the binding site. In summary, we propose a novel systematic CADD methodology for the identification, analysis, and characterization of drug-like candidates.

Design of A Cyclone Separator Using Approximation Method

NASA Astrophysics Data System (ADS)

Sin, Bong-Su; Choi, Ji-Won; Lee, Kwon-Hee

2017-12-01

A Separator is a device installed in industrial applications to separate mixed objects. The separator of interest in this research is a cyclone type, which is used to separate a steam-brine mixture in a geothermal plant. The most important performance of the cyclone separator is the collection efficiency. The collection efficiency in this study is predicted by performing the CFD (Computational Fluid Dynamics) analysis. This research defines six shape design variables to maximize the collection efficiency. Thus, the collection efficiency is set up as the objective function in optimization process. Since the CFD analysis requires a lot of calculation time, it is impossible to obtain the optimal solution by linking the gradient-based optimization algorithm. Thus, two approximation methods are introduced to obtain an optimum design. In this process, an L18 orthogonal array is adopted as a DOE method, and kriging interpolation method is adopted to generate the metamodel for the collection efficiency. Based on the 18 analysis results, the relative importance of each variable to the collection efficiency is obtained through the ANOVA (analysis of variance). The final design is suggested considering the results obtained from two optimization methods. The fluid flow analysis of the cyclone separator is conducted by using the commercial CFD software, ANSYS-CFX.

Analysis of a mammography teaching program based on an affordance design model.

PubMed

Luo, Ping; Eikman, Edward A; Kealy, William; Qian, Wei

2006-12-01

The wide use of computer technology in education, particularly in mammogram reading, asks for e-learning evaluation. The existing media comparative studies, learner attitude evaluations, and performance tests are problematic. Based on an affordance design model, this study examined an existing e-learning program on mammogram reading. The selection criteria include content relatedness, representativeness, e-learning orientation, image quality, program completeness, and accessibility. A case study was conducted to examine the affordance features, functions, and presentations of the selected software. Data collection and analysis methods include interviews, protocol-based document analysis, and usability tests and inspection. Also some statistics were calculated. The examination of PBE identified that this educational software designed and programmed some tools. The learner can use these tools in the process of optimizing displays, scanning images, comparing different projections, marking the region of interests, constructing a descriptive report, assessing one's learning outcomes, and comparing one's decisions with the experts' decisions. Further, PBE provides some resources for the learner to construct one's knowledge and skills, including a categorized image library, a term-searching function, and some teaching links. Besides, users found it easy to navigate and carry out tasks. The users also reacted positively toward PBE's navigation system, instructional aids, layout, pace and flow of information, graphics, and other presentation design. The software provides learners with some cognitive tools, supporting their perceptual problem-solving processes and extending their capabilities. Learners can internalize the mental models in mammogram reading through multiple perceptual triangulations, sensitization of related features, semantic description of mammogram findings, and expert-guided semantic report construction. The design of these cognitive tools and the software interface matches the findings and principles in human learning and instructional design. Working with PBE's case-based simulations and categorized gallery, learners can enrich and transfer their experience to their jobs.

Design and Evaluation of Glass/epoxy Composite Blade and Composite Tower Applied to Wind Turbine

NASA Astrophysics Data System (ADS)

Park, Hyunbum

2018-02-01

In the study, the analysis and manufacturing of small class wind turbine blade was performed. In the structural design, firstly the loading conditions are defined through the load case analysis. The proposed structural configuration of blade has a sandwich type composite structure with the E-glass/Epoxy face sheets and the Urethane foam core for lightness, structural stability, low manufacturing cost and easy manufacturing process. And also, this work proposes a design procedure and results of tower for the small scale wind turbine systems. Structural analysis of blade including load cases, stress, deformation, buckling, vibration and fatigue life was performed using the finite element method, the load spectrum analysis and the Miner rule. Moreover, investigation on structural safety of tower was verified through structural analysis by FEM. The manufacturing of blade and tower was performed based on structural design. In order to investigate the designed structure, the structural tests were conducted and its results were compared with the calculated results. It is confirmed that the final proposed blade and tower meet the design requirements.

SUPIN: A Computational Tool for Supersonic Inlet Design

NASA Technical Reports Server (NTRS)

Slater, John W.

2016-01-01

A computational tool named SUPIN is being developed to design and analyze the aerodynamic performance of supersonic inlets. The inlet types available include the axisymmetric pitot, three-dimensional pitot, axisymmetric outward-turning, two-dimensional single-duct, two-dimensional bifurcated-duct, and streamline-traced inlets. The aerodynamic performance is characterized by the flow rates, total pressure recovery, and drag. The inlet flow-field is divided into parts to provide a framework for the geometry and aerodynamic modeling. Each part of the inlet is defined in terms of geometric factors. The low-fidelity aerodynamic analysis and design methods are based on analytic, empirical, and numerical methods which provide for quick design and analysis. SUPIN provides inlet geometry in the form of coordinates, surface angles, and cross-sectional areas. SUPIN can generate inlet surface grids and three-dimensional, structured volume grids for use with higher-fidelity computational fluid dynamics (CFD) analysis. Capabilities highlighted in this paper include the design and analysis of streamline-traced external-compression inlets, modeling of porous bleed, and the design and analysis of mixed-compression inlets. CFD analyses are used to verify the SUPIN results.

Variation in choice of study design: findings from the Epidemiology Design Decision Inventory and Evaluation (EDDIE) survey.

PubMed

Stang, Paul E; Ryan, Patrick B; Overhage, J Marc; Schuemie, Martijn J; Hartzema, Abraham G; Welebob, Emily

2013-10-01

Researchers using observational data to understand drug effects must make a number of analytic design choices that suit the characteristics of the data and the subject of the study. Review of the published literature suggests that there is a lack of consistency even when addressing the same research question in the same database. To characterize the degree of similarity or difference in the method and analysis choices made by observational database research experts when presented with research study scenarios. On-line survey using research scenarios on drug-effect studies to capture method selection and analysis choices that follow a dependency branching based on response to key questions. Voluntary participants experienced in epidemiological study design solicited for participation through registration on the Observational Medical Outcomes Partnership website, membership in particular professional organizations, or links in relevant newsletters. Description (proportion) of respondents selecting particular methods and making specific analysis choices based on individual drug-outcome scenario pairs. The number of questions/decisions differed based on stem questions of study design, time-at-risk, outcome definition, and comparator. There is little consistency across scenarios, by drug or by outcome of interest, in the decisions made for design and analyses in scenarios using large healthcare databases. The most consistent choice was the cohort study design but variability in the other critical decisions was common. There is great variation among epidemiologists in the design and analytical choices that they make when implementing analyses in observational healthcare databases. These findings confirm that it will be important to generate empiric evidence to inform these decisions and to promote a better understanding of the impact of standardization on research implementation.

Value of information analysis optimizing future trial design from a pilot study on catheter securement devices.

PubMed

Tuffaha, Haitham W; Reynolds, Heather; Gordon, Louisa G; Rickard, Claire M; Scuffham, Paul A

2014-12-01

Value of information analysis has been proposed as an alternative to the standard hypothesis testing approach, which is based on type I and type II errors, in determining sample sizes for randomized clinical trials. However, in addition to sample size calculation, value of information analysis can optimize other aspects of research design such as possible comparator arms and alternative follow-up times, by considering trial designs that maximize the expected net benefit of research, which is the difference between the expected cost of the trial and the expected value of additional information. To apply value of information methods to the results of a pilot study on catheter securement devices to determine the optimal design of a future larger clinical trial. An economic evaluation was performed using data from a multi-arm randomized controlled pilot study comparing the efficacy of four types of catheter securement devices: standard polyurethane, tissue adhesive, bordered polyurethane and sutureless securement device. Probabilistic Monte Carlo simulation was used to characterize uncertainty surrounding the study results and to calculate the expected value of additional information. To guide the optimal future trial design, the expected costs and benefits of the alternative trial designs were estimated and compared. Analysis of the value of further information indicated that a randomized controlled trial on catheter securement devices is potentially worthwhile. Among the possible designs for the future trial, a four-arm study with 220 patients/arm would provide the highest expected net benefit corresponding to 130% return-on-investment. The initially considered design of 388 patients/arm, based on hypothesis testing calculations, would provide lower net benefit with return-on-investment of 79%. Cost-effectiveness and value of information analyses were based on the data from a single pilot trial which might affect the accuracy of our uncertainty estimation. Another limitation was that different follow-up durations for the larger trial were not evaluated. The value of information approach allows efficient trial design by maximizing the expected net benefit of additional research. This approach should be considered early in the design of randomized clinical trials. © The Author(s) 2014.

Trends in Culturally Relevant Interface Design Features for Latino Web Site Users

ERIC Educational Resources Information Center

Sachau, Lori L.; Hutchinson, Susan R.

2012-01-01

There is a lack of published research on designing Web-based instruction for the adult U.S. Latino population. Instructional designers need guidance on how to design culturally relevant learning environments for this audience, particularly for Latino people from Mexican heritage. The authors used content analysis to investigate the extent to which…

Communications Style Guide. Fourth Edition

DTIC Science & Technology

2010-08-01

ethnography , phenomenological study , grounded theory study , and content analysis. You want to choose your research design based on your topic and how you...accessed 27 May 2008). 38 design or an historical research design. There are five basic types of qualitative research designs: case study ...suits the purpose of your study . Generally, while a student of MCU, you will use qualitative research

Needs Analysis for Graphic Design Learning Module Based on Technology & Learning Styles of Deaf Students

ERIC Educational Resources Information Center

Ibrahim, Zainuddin; Alias, Norlidah; Nordin, Abu Bakar

2016-01-01

The field of Information Communication Technology has offered a promising future for deaf students. Web design, animation, and multimedia application design are a branch of graphic design area, which aim to aid their learning visually. However, most of the technical terms cannot be interpreted in Malaysian sign language. Moreover, the development…

Interoperability-oriented Integration of Failure Knowledge into Functional Knowledge and Knowledge Transformation based on Concepts Mapping

NASA Astrophysics Data System (ADS)

Koji, Yusuke; Kitamura, Yoshinobu; Kato, Yoshikiyo; Tsutsui, Yoshio; Mizoguchi, Riichiro

In conceptual design, it is important to develop functional structures which reflect the rich experience in the knowledge from previous design failures. Especially, if a designer learns possible abnormal behaviors from a previous design failure, he or she can add an additional function which prevents such abnormal behaviors and faults. To do this, it is a crucial issue to share such knowledge about possible faulty phenomena and how to cope with them. In fact, a part of such knowledge is described in FMEA (Failure Mode and Effect Analysis) sheets, function structure models for systematic design and fault trees for FTA (Fault Tree Analysis).

Analysis and optimization of hybrid excitation permanent magnet synchronous generator for stand-alone power system

NASA Astrophysics Data System (ADS)

Wang, Huijun; Qu, Zheng; Tang, Shaofei; Pang, Mingqi; Zhang, Mingju

2017-08-01

In this paper, electromagnetic design and permanent magnet shape optimization for permanent magnet synchronous generator with hybrid excitation are investigated. Based on generator structure and principle, design outline is presented for obtaining high efficiency and low voltage fluctuation. In order to realize rapid design, equivalent magnetic circuits for permanent magnet and iron poles are developed. At the same time, finite element analysis is employed. Furthermore, by means of design of experiment (DOE) method, permanent magnet is optimized to reduce voltage waveform distortion. Finally, the validity of proposed design methods is validated by the analytical and experimental results.

Multi-hazard Assessment and Scenario Toolbox (MhAST): A Framework for Analyzing Compounding Effects of Multiple Hazards

NASA Astrophysics Data System (ADS)

Sadegh, M.; Moftakhari, H.; AghaKouchak, A.

2017-12-01

Many natural hazards are driven by multiple forcing variables, and concurrence/consecutive extreme events significantly increases risk of infrastructure/system failure. It is a common practice to use univariate analysis based upon a perceived ruling driver to estimate design quantiles and/or return periods of extreme events. A multivariate analysis, however, permits modeling simultaneous occurrence of multiple forcing variables. In this presentation, we introduce the Multi-hazard Assessment and Scenario Toolbox (MhAST) that comprehensively analyzes marginal and joint probability distributions of natural hazards. MhAST also offers a wide range of scenarios of return period and design levels and their likelihoods. Contribution of this study is four-fold: 1. comprehensive analysis of marginal and joint probability of multiple drivers through 17 continuous distributions and 26 copulas, 2. multiple scenario analysis of concurrent extremes based upon the most likely joint occurrence, one ruling variable, and weighted random sampling of joint occurrences with similar exceedance probabilities, 3. weighted average scenario analysis based on a expected event, and 4. uncertainty analysis of the most likely joint occurrence scenario using a Bayesian framework.

Research and Development on Titanium Alloys

DTIC Science & Technology

1949-10-31

EVALUATION OF EPERIMENTAL TITANIUM-BASE ALLOYS• 65 Binary Alloys of Titanium . . . . .. 65 Titanium-Silver Alloys. . . . . ..... ... 68 Mechanical Properties...using a technique in melting designed to give more uniform distribution of the alloying additions. NMATTWLL MOMORIAL INSTITUTE 4...tc Dr. Derge for analysis. BATTELLE MEMORIAL INSTITUTE -107- 2TABLE 28. OXYGEN STANDARDS FOR ANALYSIS Wt fSapl Pein Cen Designation Sample lielting, 1

Analysis of Taiwanese Elementary School English Teachers' Perceptions of, Designs of, and Knowledge Constructed about Differentiated Instruction in Content

ERIC Educational Resources Information Center

Chien, Chin-Wen

2015-01-01

This study analyzed Taiwanese elementary school English teachers' perceptions of, designs on, and knowledge constructed about, differentiated instruction in content in an intensive summer course. Based on the data analysis of surveys, the document, videos, and an interview, the study had the following findings. First, before the intensive summer…

Oak Ridge Environmental Information System (OREIS) functional system design document

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

Birchfield, T.E.; Brown, M.O.; Coleman, P.R.

1994-03-01

The OREIS Functional System Design document provides a detailed functional description of the Oak Ridge Environmental Information System (OREIS). It expands the system requirements defined in the OREIS Phase 1-System Definition Document (ES/ER/TM-34). Documentation of OREIS development is based on the Automated Data Processing System Development Methodology, a Martin Marietta Energy Systems, Inc., procedure written to assist in developing scientific and technical computer systems. This document focuses on the development of the functional design of the user interface, which includes the integration of commercial applications software. The data model and data dictionary are summarized briefly; however, the Data Management Planmore » for OREIS (ES/ER/TM-39), a companion document to the Functional System Design document, provides the complete data dictionary and detailed descriptions of the requirements for the data base structure. The OREIS system will provide the following functions, which are executed from a Menu Manager: (1) preferences, (2) view manager, (3) macro manager, (4) data analysis (assisted analysis and unassisted analysis), and (5) spatial analysis/map generation (assisted ARC/INFO and unassisted ARC/INFO). Additional functionality includes interprocess communications, which handle background operations of OREIS.« less

Special Features of Using Secondary Materials in the Interior Design of Public Dining Establishments

NASA Astrophysics Data System (ADS)

Kuznetsova, Irina; Hapchuk, Olena; Lukinov, Vitaly

2017-10-01

This article analyses the latest publications studying the use and practical application of secondary resources as raw materials in design. This analysis is based on the list of secondary resources and their applications in interior decoration. In particular, the interiors of public catering enterprises were analysed. Restaurants with different functional purposes that were classified into several categories with specific peculiarities of interior design were identified. This article presents and describes different types of public catering enterprises based on those categories. The interior design of a public catering enterprise is regarded as a considerably complex system. Different types of secondary materials were reviewed to identify the most frequently used materials for interior space design. This article describes the main peculiarities of the use of secondary materials and presents examples of their practical application. The function of secondary materials in the interior design of public catering enterprises were detected and reviewed. On the basis of the analysis, several directions for the practical application of our results in the field of public catering enterprise design were suggested.

Usability evaluation of cloud-based mapping tools for the display of very large datasets

NASA Astrophysics Data System (ADS)

Stotz, Nicole Marie

The elasticity and on-demand nature of cloud services have made it easier to create web maps. Users only need access to a web browser and the Internet to utilize cloud based web maps, eliminating the need for specialized software. To encourage a wide variety of users, a map must be well designed; usability is a very important concept in designing a web map. Fusion Tables, a new product from Google, is one example of newer cloud-based distributed GIS services. It allows for easy spatial data manipulation and visualization, within the Google Maps framework. ESRI has also introduced a cloud based version of their software, called ArcGIS Online, built on Amazon's EC2 cloud. Utilizing a user-centered design framework, two prototype maps were created with data from the San Diego East County Economic Development Council. One map was built on Fusion Tables, and another on ESRI's ArcGIS Online. A usability analysis was conducted and used to compare both map prototypes in term so of design and functionality. Load tests were also ran, and performance metrics gathered on both map prototypes. The usability analysis was taken by 25 geography students, and consisted of time based tasks and questions on map design and functionality. Survey participants completed the time based tasks for the Fusion Tables map prototype quicker than those of the ArcGIS Online map prototype. While response was generally positive towards the design and functionality of both prototypes, overall the Fusion Tables map prototype was preferred. For the load tests, the data set was broken into 22 groups for a total of 44 tests. While the Fusion Tables map prototype performed more efficiently than the ArcGIS Online prototype, differences are almost unnoticeable. A SWOT analysis was conducted for each prototype. The results from this research point to the Fusion Tables map prototype. A redesign of this prototype would incorporate design suggestions from the usability survey, while some functionality would need to be dropped. This is a free product and would therefore be the best option if cost is an issue, but this map may not be supported in the future.

Terminal Restriction Fragment Length Polymorphism Analysis Program, a Web-Based Research Tool for Microbial Community Analysis

PubMed Central

Marsh, Terence L.; Saxman, Paul; Cole, James; Tiedje, James

2000-01-01

Rapid analysis of microbial communities has proven to be a difficult task. This is due, in part, to both the tremendous diversity of the microbial world and the high complexity of many microbial communities. Several techniques for community analysis have emerged over the past decade, and most take advantage of the molecular phylogeny derived from 16S rRNA comparative sequence analysis. We describe a web-based research tool located at the Ribosomal Database Project web site (http://www.cme.msu.edu/RDP/html/analyses.html) that facilitates microbial community analysis using terminal restriction fragment length polymorphism of 16S ribosomal DNA. The analysis function (designated TAP T-RFLP) permits the user to perform in silico restriction digestions of the entire 16S sequence database and derive terminal restriction fragment sizes, measured in base pairs, from the 5′ terminus of the user-specified primer to the 3′ terminus of the restriction endonuclease target site. The output can be sorted and viewed either phylogenetically or by size. It is anticipated that the site will guide experimental design as well as provide insight into interpreting results of community analysis with terminal restriction fragment length polymorphisms. PMID:10919828

Design and analysis of resonant cavity enhanced photodetector by using InP-based concentric circular subwavelength grating

NASA Astrophysics Data System (ADS)

Wang, Tingting; Huang, Yongqing; Duan, Xiaofeng; Shang, Yufeng; Wang, Wei; Ren, Xiaomin

2011-12-01

This paper presents the design and analysis of a novel resonant cavity enhanced photodetector which is realized by utilizing concentric circular subwavelength gratings (CC-SWGs) as reflective mirrors. The CC-SWG proposed here can achieve a reflectivity of higher than 99% within a broad wavelength range from 1.37 to 1.63 μm. The calculated peak quantum efficiency of the designed photodetector can achieve 90% at 1.55 μm.

A computer aided engineering tool for ECLS systems

NASA Technical Reports Server (NTRS)

Bangham, Michal E.; Reuter, James L.

1987-01-01

The Computer-Aided Systems Engineering and Analysis tool used by NASA for environmental control and life support system design studies is capable of simulating atmospheric revitalization systems, water recovery and management systems, and single-phase active thermal control systems. The designer/analysis interface used is graphics-based, and allows the designer to build a model by constructing a schematic of the system under consideration. Data management functions are performed, and the program is translated into a format that is compatible with the solution routines.

Integrated Curriculum Design Reform of Civil Engineering Management Discipline Based on Inter-disciplinary Professional Training

NASA Astrophysics Data System (ADS)

Yidong, Xu; Ping, Wu; Jian, Chen; Jiansheng, Shen

2018-05-01

In view of the shortcomings of the current civil engineering management discipline, this paper investigates the necessity of the course design reform. Based on the analysis of basic occupation requirements of civil engineering management discipline, the basic ideas and implementation strategies of the integrated reform of curriculum design system are proposed, which can not only improve the students’ overall understanding of knowledge and skills, but also enhance the system of student learning.

Recent Advances and Current Trends in Metamaterial-by-Design

NASA Astrophysics Data System (ADS)

Anselmi, N.; Gottardi, G.

2018-02-01

Thanks to their potential applications in several engineering areas, metamaterials gained much of attentions among different research communities, leading to the development of several analysis and synthesis tools. In this context, the metamaterial-by-design (MbD) paradigm has been recently introduced as a powerful tool for the design of complex metamaterials-based structures. In this work a review of the state-of-art, as well as the recent advancements of MbD-based methods are presented.

Feasibility analysis of base compaction specification : [project brief].

DOT National Transportation Integrated Search

2013-02-01

Appropriate design and construction of the aggregate base layer has significant influence on : structural stability and performance of pavements. Controlling the construction quality of : the granular base layer is important to achieve long-lasting p...

CAD-based stand-alone spacecraft radiation exposure analysis system: An application of the early man-tended Space Station

NASA Technical Reports Server (NTRS)

Appleby, M. H.; Golightly, M. J.; Hardy, A. C.

1993-01-01

Major improvements have been completed in the approach to analyses and simulation of spacecraft radiation shielding and exposure. A computer-aided design (CAD)-based system has been developed for determining the amount of shielding provided by a spacecraft and simulating transmission of an incident radiation environment to any point within or external to the vehicle. Shielding analysis is performed using a customized ray-tracing subroutine contained within a standard engineering modeling software package. This improved shielding analysis technique has been used in several vehicle design programs such as a Mars transfer habitat, pressurized lunar rover, and the redesigned international Space Station. Results of analysis performed for the Space Station astronaut exposure assessment are provided to demonastrate the applicability and versatility of the system.

Exergy analysis of helium liquefaction systems based on modified Claude cycle with two-expanders

NASA Astrophysics Data System (ADS)

Thomas, Rijo Jacob; Ghosh, Parthasarathi; Chowdhury, Kanchan

2011-06-01

Large-scale helium liquefaction systems, being energy-intensive, demand judicious selection of process parameters. An effective tool for design and analysis of thermodynamic cycles for these systems is exergy analysis, which is used to study the behavior of a helium liquefaction system based on modified Claude cycle. Parametric evaluation using process simulator Aspen HYSYS® helps to identify the effects of cycle pressure ratio and expander flow fraction on the exergetic efficiency of the liquefaction cycle. The study computes the distribution of losses at different refrigeration stages of the cycle and helps in selecting optimum cycle pressures, operating temperature levels of expanders and mass flow rates through them. Results from the analysis may help evolving guidelines for designing appropriate thermodynamic cycles for practical helium liquefaction systems.

Integrating Flight Dynamics & Control Analysis and Simulation in Rotorcraft Conceptual Design

NASA Technical Reports Server (NTRS)

Lawrence, Ben; Berger, Tom; Tischler, Mark B.; Theodore, Colin R; Elmore, Josh; Gallaher, Andrew; Tobias, Eric L.

2016-01-01

The development of a toolset, SIMPLI-FLYD ('SIMPLIfied FLight dynamics for conceptual Design') is described. SIMPLI-FLYD is a collection of tools that perform flight dynamics and control modeling and analysis of rotorcraft conceptual designs including a capability to evaluate the designs in an X-Plane-based real-time simulation. The establishment of this framework is now facilitating the exploration of this new capability, in terms of modeling fidelity and data requirements, and the investigation of which stability and control and handling qualities requirements are appropriate for conceptual design. Illustrative design variation studies for single main rotor and tiltrotor vehicle configurations show sensitivity of the stability and control characteristics and an approach to highlight potential weight savings by identifying over-design.

Design and analysis of a stiffened composite fuselage panel

NASA Technical Reports Server (NTRS)

Dickson, J. N.; Biggers, S. B.

1980-01-01

The design and analysis of stiffened composite panel that is representative of the fuselage structure of existing wide bodied aircraft is discussed. The panel is a minimum weight design, based on the current level of technology and realistic loads and criteria. Several different stiffener configurations were investigated in the optimization process. The final configuration is an all graphite/epoxy J-stiffened design in which the skin between adjacent stiffeners is permitted to buckle under design loads. Fail safe concepts typically employed in metallic fuselage structure have been incorporated in the design. A conservative approach has been used with regard to structural details such as skin/frame and stringer/frame attachments and other areas where sufficient design data was not available.

An Analysis of Risk and Function Information in Early Stage Design

NASA Technical Reports Server (NTRS)

Barrientos, Francesca; Tumer, Irem; Grantham, Katie; VanWie, Michael; Stone, Robert

2005-01-01

The concept of function offers a high potential for thinking and reasoning about designs as well as providing a common thread for relating together other design information. This paper focuses specifically on the relation between function and risk by examining how this information is addressed for a design team conducting early stage design for space missions. Risk information is decomposed into a set of key attributes which are then used to scrutinize the risk information using three approaches from the pragmatics sub-field of linguistics: i) Gricean, ii) Relevance Theory, and Functional Analysis. Results of this linguistics-based approach descriptively account for the context of designer communication with respect to function and risk, and offer prescriptive guidelines for improving designer communication.

DEPEND: A simulation-based environment for system level dependability analysis

NASA Technical Reports Server (NTRS)

Goswami, Kumar; Iyer, Ravishankar K.

1992-01-01

The design and evaluation of highly reliable computer systems is a complex issue. Designers mostly develop such systems based on prior knowledge and experience and occasionally from analytical evaluations of simplified designs. A simulation-based environment called DEPEND which is especially geared for the design and evaluation of fault-tolerant architectures is presented. DEPEND is unique in that it exploits the properties of object-oriented programming to provide a flexible framework with which a user can rapidly model and evaluate various fault-tolerant systems. The key features of the DEPEND environment are described, and its capabilities are illustrated with a detailed analysis of a real design. In particular, DEPEND is used to simulate the Unix based Tandem Integrity fault-tolerance and evaluate how well it handles near-coincident errors caused by correlated and latent faults. Issues such as memory scrubbing, re-integration policies, and workload dependent repair times which affect how the system handles near-coincident errors are also evaluated. Issues such as the method used by DEPEND to simulate error latency and the time acceleration technique that provides enormous simulation speed up are also discussed. Unlike any other simulation-based dependability studies, the use of these approaches and the accuracy of the simulation model are validated by comparing the results of the simulations, with measurements obtained from fault injection experiments conducted on a production Tandem Integrity machine.

HSI top-down requirements analysis for ship manpower reduction

NASA Astrophysics Data System (ADS)

Malone, Thomas B.; Bost, J. R.

2000-11-01

U.S. Navy ship acquisition programs such as DD 21 and CVNX are increasingly relying on top down requirements analysis (TDRA) to define and assess design approaches for workload and manpower reduction, and for ensuring required levels of human performance, reliability, safety, and quality of life at sea. The human systems integration (HSI) approach to TDRA begins with a function analysis which identifies the functions derived from the requirements in the Operational Requirements Document (ORD). The function analysis serves as the function baseline for the ship, and also supports the definition of RDT&E and Total Ownership Cost requirements. A mission analysis is then conducted to identify mission scenarios, again based on requirements in the ORD, and the Design Reference Mission (DRM). This is followed by a mission/function analysis which establishes the function requirements to successfully perform the ship's missions. Function requirements of major importance for HSI are information, performance, decision, and support requirements associated with each function. An allocation of functions defines the roles of humans and automation in performing the functions associated with a mission. Alternate design concepts, based on function allocation strategies, are then described, and task networks associated with the concepts are developed. Task network simulations are conducted to assess workloads and human performance capabilities associated with alternate concepts. An assessment of the affordability and risk associated with alternate concepts is performed, and manning estimates are developed for feasible design concepts.

Statistical design of quantitative mass spectrometry-based proteomic experiments.

PubMed

Oberg, Ann L; Vitek, Olga

2009-05-01

We review the fundamental principles of statistical experimental design, and their application to quantitative mass spectrometry-based proteomics. We focus on class comparison using Analysis of Variance (ANOVA), and discuss how randomization, replication and blocking help avoid systematic biases due to the experimental procedure, and help optimize our ability to detect true quantitative changes between groups. We also discuss the issues of pooling multiple biological specimens for a single mass analysis, and calculation of the number of replicates in a future study. When applicable, we emphasize the parallels between designing quantitative proteomic experiments and experiments with gene expression microarrays, and give examples from that area of research. We illustrate the discussion using theoretical considerations, and using real-data examples of profiling of disease.

Mechanical Design of Downhole Tractor Based on Two-Way Self-locking Mechanism

NASA Astrophysics Data System (ADS)

Fang, Delei; Shang, Jianzhong; Luo, Zirong; Wu, Guoheng; Liu, Yiying

2018-03-01

Based on the technology of horizontal well tractor, a kind of downhole tractor was developed which can realize Two-Way self-locking function. Aiming at the needs of horizontal well logging to realize the target of small size, high traction and high reliability, the tractor selects unique heart-shaped CAM as the locking mechanism. The motion principle of telescopic downhole tractor, the design of mechanical structure and locking principle of the locking mechanism are all analyzed. The mathematical expressions of traction are obtained by mechanical analysis of parallel support rod in the locking mechanism. The force analysis and contour design of the heart-shaped CAM are performed, which can lay the foundation for the development of tractor prototype.

Strategies and Approaches to TPS Design

NASA Technical Reports Server (NTRS)

Kolodziej, Paul

2005-01-01

Thermal protection systems (TPS) insulate planetary probes and Earth re-entry vehicles from the aerothermal heating experienced during hypersonic deceleration to the planet s surface. The systems are typically designed with some additional capability to compensate for both variations in the TPS material and for uncertainties in the heating environment. This additional capability, or robustness, also provides a surge capability for operating under abnormal severe conditions for a short period of time, and for unexpected events, such as meteoroid impact damage, that would detract from the nominal performance. Strategies and approaches to developing robust designs must also minimize mass because an extra kilogram of TPS displaces one kilogram of payload. Because aircraft structures must be optimized for minimum mass, reliability-based design approaches for mechanical components exist that minimize mass. Adapting these existing approaches to TPS component design takes advantage of the extensive work, knowledge, and experience from nearly fifty years of reliability-based design of mechanical components. A Non-Dimensional Load Interference (NDLI) method for calculating the thermal reliability of TPS components is presented in this lecture and applied to several examples. A sensitivity analysis from an existing numerical simulation of a carbon phenolic TPS provides insight into the effects of the various design parameters, and is used to demonstrate how sensitivity analysis may be used with NDLI to develop reliability-based designs of TPS components.

Design of spur-type streambank stabilization structures.

DOT National Transportation Integrated Search

1985-07-01

streambank stabilization structures has been conducted to establish design guidelines and other criteria for the use of spurs. The recommendations and findings are based on a thorough review of pertinent literature, analysis of several hundred field ...

Polarimetric receiver in the forty gigahertz band: new instrument for the Q-U-I joint Tenerife experiment

NASA Astrophysics Data System (ADS)

Villa, Enrique; Cano, Juan L.; Aja, Beatriz; Terán, J. Vicente; de la Fuente, Luisa; Mediavilla, Ángel; Artal, Eduardo

2018-03-01

This paper describes the analysis, design and characterization of a polarimetric receiver developed for covering the 35 to 47 GHz frequency band in the new instrument aimed at completing the ground-based Q-U-I Joint Tenerife Experiment. This experiment is designed to measure polarization in the Cosmic Microwave Background. The described high frequency instrument is a HEMT-based array composed of 29 pixels. A thorough analysis of the behaviour of the proposed receiver, based on electronic phase switching, is presented for a noise-like linearly polarized input signal, obtaining simultaneously I, Q and U Stokes parameters of the input signal. Wideband subsystems are designed, assembled and characterized for the polarimeter. Their performances are described showing appropriate results within the 35-to-47 GHz frequency band. Functionality tests are performed at room and cryogenic temperatures with adequate results for both temperature conditions, which validate the receiver concept and performance.

Performance evaluation of a lossy transmission lines based diode detector at cryogenic temperature.

PubMed

Villa, E; Aja, B; de la Fuente, L; Artal, E

2016-01-01

This work is focused on the design, fabrication, and performance analysis of a square-law Schottky diode detector based on lossy transmission lines working under cryogenic temperature (15 K). The design analysis of a microwave detector, based on a planar gallium-arsenide low effective Schottky barrier height diode, is reported, which is aimed for achieving large input return loss as well as flat sensitivity versus frequency. The designed circuit demonstrates good sensitivity, as well as a good return loss in a wide bandwidth at Ka-band, at both room (300 K) and cryogenic (15 K) temperatures. A good sensitivity of 1000 mV/mW and input return loss better than 12 dB have been achieved when it works as a zero-bias Schottky diode detector at room temperature, increasing the sensitivity up to a minimum of 2200 mV/mW, with the need of a DC bias current, at cryogenic temperature.

Development of computer-aided design system of elastic sensitive elements of automatic metering devices

NASA Astrophysics Data System (ADS)

Kalinkina, M. E.; Kozlov, A. S.; Labkovskaia, R. I.; Pirozhnikova, O. I.; Tkalich, V. L.; Shmakov, N. A.

2018-05-01

The object of research is the element base of devices of control and automation systems, including in its composition annular elastic sensitive elements, methods of their modeling, calculation algorithms and software complexes for automation of their design processes. The article is devoted to the development of the computer-aided design system of elastic sensitive elements used in weight- and force-measuring automation devices. Based on the mathematical modeling of deformation processes in a solid, as well as the results of static and dynamic analysis, the calculation of elastic elements is given using the capabilities of modern software systems based on numerical simulation. In the course of the simulation, the model was a divided hexagonal grid of finite elements with a maximum size not exceeding 2.5 mm. The results of modal and dynamic analysis are presented in this article.

DNA "nano-claw": logic-based autonomous cancer targeting and therapy.

PubMed

You, Mingxu; Peng, Lu; Shao, Na; Zhang, Liqin; Qiu, Liping; Cui, Cheng; Tan, Weihong

2014-01-29

Cell types, both healthy and diseased, can be classified by inventories of their cell-surface markers. Programmable analysis of multiple markers would enable clinicians to develop a comprehensive disease profile, leading to more accurate diagnosis and intervention. As a first step to accomplish this, we have designed a DNA-based device, called "Nano-Claw". Combining the special structure-switching properties of DNA aptamers with toehold-mediated strand displacement reactions, this claw is capable of performing autonomous logic-based analysis of multiple cancer cell-surface markers and, in response, producing a diagnostic signal and/or targeted photodynamic therapy. We anticipate that this design can be widely applied in facilitating basic biomedical research, accurate disease diagnosis, and effective therapy.

Microfluidic-Based Robotic Sampling System for Radioactive Solutions

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

Jack D. Law; Julia L. Tripp; Tara E. Smith

A novel microfluidic based robotic sampling system has been developed for sampling and analysis of liquid solutions in nuclear processes. This system couples the use of a microfluidic sample chip with a robotic system designed to allow remote, automated sampling of process solutions in-cell and facilitates direct coupling of the microfluidic sample chip with analytical instrumentation. This system provides the capability for near real time analysis, reduces analytical waste, and minimizes the potential for personnel exposure associated with traditional sampling methods. A prototype sampling system was designed, built and tested. System testing demonstrated operability of the microfluidic based sample systemmore » and identified system modifications to optimize performance.« less

Dynamic Systems Analysis for Turbine Based Aero Propulsion Systems

NASA Technical Reports Server (NTRS)

Csank, Jeffrey T.

2016-01-01

The aircraft engine design process seeks to optimize the overall system-level performance, weight, and cost for a given concept. Steady-state simulations and data are used to identify trade-offs that should be balanced to optimize the system in a process known as systems analysis. These systems analysis simulations and data may not adequately capture the true performance trade-offs that exist during transient operation. Dynamic systems analysis provides the capability for assessing the dynamic tradeoffs at an earlier stage of the engine design process. The dynamic systems analysis concept, developed tools, and potential benefit are presented in this paper. To provide this capability, the Tool for Turbine Engine Closed-loop Transient Analysis (TTECTrA) was developed to provide the user with an estimate of the closed-loop performance (response time) and operability (high pressure compressor surge margin) for a given engine design and set of control design requirements. TTECTrA along with engine deterioration information, can be used to develop a more generic relationship between performance and operability that can impact the engine design constraints and potentially lead to a more efficient engine.

European Design Types for 21st Century Schools: An Overview

ERIC Educational Resources Information Center

Rigolon, Alessandro

2010-01-01

This article presents a critical overview of European school building design types, based on an analysis of morphologies and spatial layouts. The different design types are evaluated in function of specific didactic and social needs. (Contains 1 figure, 18 footnotes, a bibliography and 2 online resources.)

Guidelines for Implementing NCHRP 1-37A M-E Design Procedures in Ohio : Volume 3 -- Sensitivity Analysis

DOT National Transportation Integrated Search

2009-11-01

The new Mechanistic-Empirical Pavement Design Guide (NCHRP 1-37A and 1-40D) is based on fundamental engineering principles and is far more comprehensive than the current empirical AASHTO Design Guide developed for conditions more than 40 years previo...

Project-Based Teaching-Learning Computer-Aided Engineering Tools

ERIC Educational Resources Information Center

Simoes, J. A.; Relvas, C.; Moreira, R.

2004-01-01

Computer-aided design, computer-aided manufacturing, computer-aided analysis, reverse engineering and rapid prototyping are tools that play an important key role within product design. These are areas of technical knowledge that must be part of engineering and industrial design courses' curricula. This paper describes our teaching experience of…

Multi-mode reliability-based design of horizontal curves.

PubMed

Essa, Mohamed; Sayed, Tarek; Hussein, Mohamed

2016-08-01

Recently, reliability analysis has been advocated as an effective approach to account for uncertainty in the geometric design process and to evaluate the risk associated with a particular design. In this approach, a risk measure (e.g. probability of noncompliance) is calculated to represent the probability that a specific design would not meet standard requirements. The majority of previous applications of reliability analysis in geometric design focused on evaluating the probability of noncompliance for only one mode of noncompliance such as insufficient sight distance. However, in many design situations, more than one mode of noncompliance may be present (e.g. insufficient sight distance and vehicle skidding at horizontal curves). In these situations, utilizing a multi-mode reliability approach that considers more than one failure (noncompliance) mode is required. The main objective of this paper is to demonstrate the application of multi-mode (system) reliability analysis to the design of horizontal curves. The process is demonstrated by a case study of Sea-to-Sky Highway located between Vancouver and Whistler, in southern British Columbia, Canada. Two noncompliance modes were considered: insufficient sight distance and vehicle skidding. The results show the importance of accounting for several noncompliance modes in the reliability model. The system reliability concept could be used in future studies to calibrate the design of various design elements in order to achieve consistent safety levels based on all possible modes of noncompliance. Copyright © 2016 Elsevier Ltd. All rights reserved.

Toxic release consequence analysis tool (TORCAT) for inherently safer design plant.

PubMed

Shariff, Azmi Mohd; Zaini, Dzulkarnain

2010-10-15

Many major accidents due to toxic release in the past have caused many fatalities such as the tragedy of MIC release in Bhopal, India (1984). One of the approaches is to use inherently safer design technique that utilizes inherent safety principle to eliminate or minimize accidents rather than to control the hazard. This technique is best implemented in preliminary design stage where the consequence of toxic release can be evaluated and necessary design improvements can be implemented to eliminate or minimize the accidents to as low as reasonably practicable (ALARP) without resorting to costly protective system. However, currently there is no commercial tool available that has such capability. This paper reports on the preliminary findings on the development of a prototype tool for consequence analysis and design improvement via inherent safety principle by utilizing an integrated process design simulator with toxic release consequence analysis model. The consequence analysis based on the worst-case scenarios during process flowsheeting stage were conducted as case studies. The preliminary finding shows that toxic release consequences analysis tool (TORCAT) has capability to eliminate or minimize the potential toxic release accidents by adopting the inherent safety principle early in preliminary design stage. 2010 Elsevier B.V. All rights reserved.

Simulation of Blood flow in Different Configurations Design of Bi-leaflet Mechanical Heart Valve

NASA Astrophysics Data System (ADS)

Hafizah Mokhtar, N.; Abas, Aizat

2018-05-01

In this work, two different designs of artificial heart valve were devised and then compared by considering the thrombosis, wear and valve orifice to anatomical orifice ratio of each mechanical heart valve. These different design configurations of bi-leaflet mechanical heart valves model are created through the use of Computer-aided design (CAD) modelling and simulated using Computational fluid dynamic (CFD) software. Design 1 is based on existing conventional bi-leaflet valve and design 2 based on modified bi-leaflet respectively. The flow pattern, velocity, vorticity and stress analysis have been done to justify the best design. Based on results, both of the designs show a Doppler velocity index of less than the allowable standard of 2.2 which is safe to be used as replacement of the human heart valve. However, design 2 shows that it has a lower possibility of cavitation issue which will lead to lower thrombosis and provide good central flow area of blood as compared to design 1.