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Sample records for computer-aided design tool

  1. Accelerating Battery Design Using Computer-Aided Engineering Tools: Preprint

    SciTech Connect

    Pesaran, A.; Heon, G. H.; Smith, K.

    2011-01-01

    Computer-aided engineering (CAE) is a proven pathway, especially in the automotive industry, to improve performance by resolving the relevant physics in complex systems, shortening the product development design cycle, thus reducing cost, and providing an efficient way to evaluate parameters for robust designs. Academic models include the relevant physics details, but neglect engineering complexities. Industry models include the relevant macroscopic geometry and system conditions, but simplify the fundamental physics too much. Most of the CAE battery tools for in-house use are custom model codes and require expert users. There is a need to make these battery modeling and design tools more accessible to end users such as battery developers, pack integrators, and vehicle makers. Developing integrated and physics-based CAE battery tools can reduce the design, build, test, break, re-design, re-build, and re-test cycle and help lower costs. NREL has been involved in developing various models to predict the thermal and electrochemical performance of large-format cells and has used in commercial three-dimensional finite-element analysis and computational fluid dynamics to study battery pack thermal issues. These NREL cell and pack design tools can be integrated to help support the automotive industry and to accelerate battery design.

  2. WASTE REDUCTION USING COMPUTER-AIDED DESIGN TOOLS

    EPA Science Inventory

    Growing environmental concerns have spurred considerable interest in pollution prevention. In most instances, pollution prevention involves introducing radical changes to the design of processes so that waste generation is minimized.
    Process simulators can be effective tools i...

  3. Computer-aided design tools for economical MEMS fabrication processes

    NASA Astrophysics Data System (ADS)

    Schneider, Christian; Priebe, Andreas; Brueck, Rainer; Hahn, Kai

    1999-03-01

    Since the early 70s when microsystem technology was first introduce an enormous market for MST-products has been developed. Airbag sensors, micro pumps, ink jet nozzles etc. and the market is just about to start up. Establishing these products for a reasonable price requires mass production. Meanwhile, also computer-based design-tools have been developed in order to reduce the expenses for MST-design. In contrast to other physical design processes like e.g. in micro electronics, MEMS physical design is characterized by the fact that each product requires a tailored sequence of fabrication steps, usually selected from a variety of processing alternatives. The selection from these alternatives is based on economical constraints. Therefore, the design has a strong influence on the money and time spent to take an MST-product to market.

  4. Technology and Jobs: Computer-Aided Design. Numerical-Control Machine-Tool Operators. Office Automation.

    ERIC Educational Resources Information Center

    Stanton, Michael; And Others

    1985-01-01

    Three reports on the effects of high technology on the nature of work include (1) Stanton on applications and implications of computer-aided design for engineers, drafters, and architects; (2) Nardone on the outlook and training of numerical-control machine tool operators; and (3) Austin and Drake on the future of clerical occupations in automated…

  5. Computer Aided Engineering Design

    NASA Astrophysics Data System (ADS)

    Saxena, Anupam; Sahay, Birendra

    This book amalgamates geometric modelling, analysis and optimization, the three important aspects in Computer Aided Engineering Design. While the three subjects are well developed by themselves, a detailed discussion on engineering visualization (transformations and projections) and mathematical background of free form, parametric and piecewise design of curves and surfaces is provided. A topological basis is given when discussing wireframe, boundary representation and constructive solid geometry as solid modelling techniques. http://www.springeronline.com/alert/article?a=3D1_1fva7w_9hjul_18j_6

  6. Analytical Design Package (ADP2): A computer aided engineering tool for aircraft transparency design

    NASA Technical Reports Server (NTRS)

    Wuerer, J. E.; Gran, M.; Held, T. W.

    1994-01-01

    The Analytical Design Package (ADP2) is being developed as a part of the Air Force Frameless Transparency Program (FTP). ADP2 is an integrated design tool consisting of existing analysis codes and Computer Aided Engineering (CAE) software. The objective of the ADP2 is to develop and confirm an integrated design methodology for frameless transparencies, related aircraft interfaces, and their corresponding tooling. The application of this methodology will generate high confidence for achieving a qualified part prior to mold fabrication. ADP2 is a customized integration of analysis codes, CAE software, and material databases. The primary CAE integration tool for the ADP2 is P3/PATRAN, a commercial-off-the-shelf (COTS) software tool. The open architecture of P3/PATRAN allows customized installations with different applications modules for specific site requirements. Integration of material databases allows the engineer to select a material, and those material properties are automatically called into the relevant analysis code. The ADP2 materials database will be composed of four independent schemas: CAE Design, Processing, Testing, and Logistics Support. The design of ADP2 places major emphasis on the seamless integration of CAE and analysis modules with a single intuitive graphical interface. This tool is being designed to serve and be used by an entire project team, i.e., analysts, designers, materials experts, and managers. The final version of the software will be delivered to the Air Force in Jan. 1994. The Analytical Design Package (ADP2) will then be ready for transfer to industry. The package will be capable of a wide range of design and manufacturing applications.

  7. Computer-aided drug designing.

    PubMed

    Gore, Mohini; Desai, Neetin S

    2014-01-01

    Computer-aided drug designing has emerged as a cost-effective and rapid tool for the discovery of newer therapeutic agents. Several algorithms have been developed to analyze protein structure and function, to identify interacting ligands, active site residues, and to study protein-ligand interactions, which can eventually lead to the identification of new drugs. In silico drug designing involves identification of the target protein which is responsible for the development of the disease under study. The three-dimensional structure of the protein can be predicted using homology modeling, while molecular docking is applied to study the interaction of a drug molecule with the protein. The best orientation of the ligand-protein docked structure which has overall minimum energy needs to be obtained. In silico methods can be used to identify potential drugs for various diseases. Thus, computer-aided drug designing has become an indispensible and integral part of the drug discovery process. PMID:24870144

  8. Validation of space/ground antenna control algorithms using a computer-aided design tool

    NASA Technical Reports Server (NTRS)

    Gantenbein, Rex E.

    1995-01-01

    The validation of the algorithms for controlling the space-to-ground antenna subsystem for Space Station Alpha is an important step in assuring reliable communications. These algorithms have been developed and tested using a simulation environment based on a computer-aided design tool that can provide a time-based execution framework with variable environmental parameters. Our work this summer has involved the exploration of this environment and the documentation of the procedures used to validate these algorithms. We have installed a variety of tools in a laboratory of the Tracking and Communications division for reproducing the simulation experiments carried out on these algorithms to verify that they do meet their requirements for controlling the antenna systems. In this report, we describe the processes used in these simulations and our work in validating the tests used.

  9. Accelerating Design of Batteries Using Computer-Aided Engineering Tools (Presentation)

    SciTech Connect

    Pesaran, A.; Kim, G. H.; Smith, K.

    2010-11-01

    Computer-aided engineering (CAE) is a proven pathway, especially in the automotive industry, to improve performance by resolving the relevant physics in complex systems, shortening the product development design cycle, thus reducing cost, and providing an efficient way to evaluate parameters for robust designs. Academic models include the relevant physics details, but neglect engineering complexities. Industry models include the relevant macroscopic geometry and system conditions, but simplify the fundamental physics too much. Most of the CAE battery tools for in-house use are custom model codes and require expert users. There is a need to make these battery modeling and design tools more accessible to end users such as battery developers, pack integrators, and vehicle makers. Developing integrated and physics-based CAE battery tools can reduce the design, build, test, break, re-design, re-build, and re-test cycle and help lower costs. NREL has been involved in developing various models to predict the thermal and electrochemical performance of large-format cells and has used in commercial three-dimensional finite-element analysis and computational fluid dynamics to study battery pack thermal issues. These NREL cell and pack design tools can be integrated to help support the automotive industry and to accelerate battery design.

  10. Computer-aided system design

    NASA Technical Reports Server (NTRS)

    Walker, Carrie K.

    1991-01-01

    A technique has been developed for combining features of a systems architecture design and assessment tool and a software development tool. This technique reduces simulation development time and expands simulation detail. The Architecture Design and Assessment System (ADAS), developed at the Research Triangle Institute, is a set of computer-assisted engineering tools for the design and analysis of computer systems. The ADAS system is based on directed graph concepts and supports the synthesis and analysis of software algorithms mapped to candidate hardware implementations. Greater simulation detail is provided by the ADAS functional simulator. With the functional simulator, programs written in either Ada or C can be used to provide a detailed description of graph nodes. A Computer-Aided Software Engineering tool developed at the Charles Stark Draper Laboratory (CSDL CASE) automatically generates Ada or C code from engineering block diagram specifications designed with an interactive graphical interface. A technique to use the tools together has been developed, which further automates the design process.

  11. Computer-Aided Design (CAD).

    ERIC Educational Resources Information Center

    Burns, William E.

    1986-01-01

    Discusses the field of computer-aided design, which combines the skills and creativity of the architect, designer, drafter, and engineer with the power of the computer. Reports on job tasks, applications, background of the field, job outlook, and necessary training. (CH)

  12. Computer aided airship design

    NASA Technical Reports Server (NTRS)

    Davis, S. J.; Rosenstein, H.

    1975-01-01

    The Comprehensive Airship Sizing and Performance Computer Program (CASCOMP) is described which was developed and used in the design and evaluation of advanced lighter-than-air (LTA) craft. The program defines design details such as engine size and number, component weight buildups, required power, and the physical dimensions of airships which are designed to meet specified mission requirements. The program is used in a comparative parametric evaluation of six advanced lighter-than-air concepts. The results indicate that fully buoyant conventional airships have the lightest gross lift required when designed for speeds less than 100 knots and the partially buoyant concepts are superior above 100 knots. When compared on the basis of specific productivity, which is a measure of the direct operating cost, the partially buoyant lifting body/tilting prop-rotor concept is optimum.

  13. Computer Aided Control System Design (CACSD)

    NASA Technical Reports Server (NTRS)

    Stoner, Frank T.

    1993-01-01

    The design of modern aerospace systems relies on the efficient utilization of computational resources and the availability of computational tools to provide accurate system modeling. This research focuses on the development of a computer aided control system design application which provides a full range of stability analysis and control design capabilities for aerospace vehicles.

  14. LIFESPAN: A tool for the computer-aided design of longitudinal studies

    PubMed Central

    Brandmaier, Andreas M.; von Oertzen, Timo; Ghisletta, Paolo; Hertzog, Christopher; Lindenberger, Ulman

    2015-01-01

    Researchers planning a longitudinal study typically search, more or less informally, a multivariate space of possible study designs that include dimensions such as the hypothesized true variance in change, indicator reliability, the number and spacing of measurement occasions, total study time, and sample size. The main search goal is to select a research design that best addresses the guiding questions and hypotheses of the planned study while heeding applicable external conditions and constraints, including time, money, feasibility, and ethical considerations. Because longitudinal study selection ultimately requires optimization under constraints, it is amenable to the general operating principles of optimization in computer-aided design. Based on power equivalence theory (MacCallum et al., 2010; von Oertzen, 2010), we propose a computational framework to promote more systematic searches within the study design space. Starting with an initial design, the proposed framework generates a set of alternative models with equal statistical power to detect hypothesized effects, and delineates trade-off relations among relevant parameters, such as total study time and the number of measurement occasions. We present LIFESPAN (Longitudinal Interactive Front End Study Planner), which implements this framework. LIFESPAN boosts the efficiency, breadth, and precision of the search for optimal longitudinal designs. Its initial version, which is freely available at http://www.brandmaier.de/lifespan, is geared toward the power to detect variance in change as specified in a linear latent growth curve model. PMID:25852596

  15. LIFESPAN: A tool for the computer-aided design of longitudinal studies.

    PubMed

    Brandmaier, Andreas M; von Oertzen, Timo; Ghisletta, Paolo; Hertzog, Christopher; Lindenberger, Ulman

    2015-01-01

    Researchers planning a longitudinal study typically search, more or less informally, a multivariate space of possible study designs that include dimensions such as the hypothesized true variance in change, indicator reliability, the number and spacing of measurement occasions, total study time, and sample size. The main search goal is to select a research design that best addresses the guiding questions and hypotheses of the planned study while heeding applicable external conditions and constraints, including time, money, feasibility, and ethical considerations. Because longitudinal study selection ultimately requires optimization under constraints, it is amenable to the general operating principles of optimization in computer-aided design. Based on power equivalence theory (MacCallum et al., 2010; von Oertzen, 2010), we propose a computational framework to promote more systematic searches within the study design space. Starting with an initial design, the proposed framework generates a set of alternative models with equal statistical power to detect hypothesized effects, and delineates trade-off relations among relevant parameters, such as total study time and the number of measurement occasions. We present LIFESPAN (Longitudinal Interactive Front End Study Planner), which implements this framework. LIFESPAN boosts the efficiency, breadth, and precision of the search for optimal longitudinal designs. Its initial version, which is freely available at http://www.brandmaier.de/lifespan, is geared toward the power to detect variance in change as specified in a linear latent growth curve model. PMID:25852596

  16. Geometric modeling for computer aided design

    NASA Technical Reports Server (NTRS)

    Schwing, James L.

    1992-01-01

    The goal was the design and implementation of software to be used in the conceptual design of aerospace vehicles. Several packages and design studies were completed, including two software tools currently used in the conceptual level design of aerospace vehicles. These tools are the Solid Modeling Aerospace Research Tool (SMART) and the Environment for Software Integration and Execution (EASIE). SMART provides conceptual designers with a rapid prototyping capability and additionally provides initial mass property analysis. EASIE provides a set of interactive utilities that simplify the task of building and executing computer aided design systems consisting of diverse, stand alone analysis codes that result in the streamlining of the exchange of data between programs, reducing errors and improving efficiency.

  17. Geometric modeling for computer aided design

    NASA Technical Reports Server (NTRS)

    Schwing, James L.

    1993-01-01

    Over the past several years, it has been the primary goal of this grant to design and implement software to be used in the conceptual design of aerospace vehicles. The work carried out under this grant was performed jointly with members of the Vehicle Analysis Branch (VAB) of NASA LaRC, Computer Sciences Corp., and Vigyan Corp. This has resulted in the development of several packages and design studies. Primary among these are the interactive geometric modeling tool, the Solid Modeling Aerospace Research Tool (smart), and the integration and execution tools provided by the Environment for Application Software Integration and Execution (EASIE). In addition, it is the purpose of the personnel of this grant to provide consultation in the areas of structural design, algorithm development, and software development and implementation, particularly in the areas of computer aided design, geometric surface representation, and parallel algorithms.

  18. Computer Aided Design in Engineering Education.

    ERIC Educational Resources Information Center

    Gobin, R.

    1986-01-01

    Discusses the use of Computer Aided Design (CAD) and Computer Aided Manufacturing (CAM) systems in an undergraduate engineering education program. Provides a rationale for CAD/CAM use in the already existing engineering program. Describes the methods used in choosing the systems, some initial results, and warnings for first-time users. (TW)

  19. Integrated computer-aided design using minicomputers

    NASA Technical Reports Server (NTRS)

    Storaasli, O. O.

    1980-01-01

    Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM), a highly interactive software, has been implemented on minicomputers at the NASA Langley Research Center. CAD/CAM software integrates many formerly fragmented programs and procedures into one cohesive system; it also includes finite element modeling and analysis, and has been interfaced via a computer network to a relational data base management system and offline plotting devices on mainframe computers. The CAD/CAM software system requires interactive graphics terminals operating at a minimum of 4800 bits/sec transfer rate to a computer. The system is portable and introduces 'interactive graphics', which permits the creation and modification of models interactively. The CAD/CAM system has already produced designs for a large area space platform, a national transonic facility fan blade, and a laminar flow control wind tunnel model. Besides the design/drafting element analysis capability, CAD/CAM provides options to produce an automatic program tooling code to drive a numerically controlled (N/C) machine. Reductions in time for design, engineering, drawing, finite element modeling, and N/C machining will benefit productivity through reduced costs, fewer errors, and a wider range of configuration.

  20. Purchasing Computer-Aided Design Software.

    ERIC Educational Resources Information Center

    Smith, Roger A.

    1992-01-01

    Presents a model for the purchase of computer-aided design (CAD) software: collect general information, observe CAD in use, arrange onsite demonstrations, select CAD software and hardware, and choose a vendor. (JOW)

  1. Caesy: A software tool for computer-aided engineering

    NASA Technical Reports Server (NTRS)

    Wette, Matt

    1993-01-01

    A new software tool, Caesy, is described. This tool provides a strongly typed programming environment for research in the development of algorithms and software for computer-aided control system design. A description of the user language and its implementation as they currently stand are presented along with a description of work in progress and areas of future work.

  2. Computer Aided Drafting and Design, Industrial Manufacturing Technician, and Mechanical Engineering Technician and Machine Tool, Die and Moldmaking Technology. Tech Prep Competency Profile.

    ERIC Educational Resources Information Center

    Mid-East Ohio Tech Prep Consortium, Zanesville.

    This document contains competency profiles in four areas: computer-aided drafting and design; industrial manufacturing technician; mechanical engineering technician; and machine tool, die, and moldmaking technology occupations. The profiles are intended for use in articulating tech prep programs from high school through associate degrees in Ohio.…

  3. Computer-Aided Drafting and Design Series. Educational Resources for the Machine Tool Industry, Course Syllabi, [and] Instructor's Handbook. Student Laboratory Manual.

    ERIC Educational Resources Information Center

    Texas State Technical Coll. System, Waco.

    This package consists of course syllabi, an instructor's handbook, and a student laboratory manual for a 2-year vocational training program to prepare students for entry-level employment in computer-aided drafting and design in the machine tool industry. The program was developed through a modification of the DACUM (Developing a Curriculum)…

  4. Geometric modeling for computer aided design

    NASA Technical Reports Server (NTRS)

    Schwing, James L.; Olariu, Stephen

    1995-01-01

    The primary goal of this grant has been the design and implementation of software to be used in the conceptual design of aerospace vehicles particularly focused on the elements of geometric design, graphical user interfaces, and the interaction of the multitude of software typically used in this engineering environment. This has resulted in the development of several analysis packages and design studies. These include two major software systems currently used in the conceptual level design of aerospace vehicles. These tools are SMART, the Solid Modeling Aerospace Research Tool, and EASIE, the Environment for Software Integration and Execution. Additional software tools were designed and implemented to address the needs of the engineer working in the conceptual design environment. SMART provides conceptual designers with a rapid prototyping capability and several engineering analysis capabilities. In addition, SMART has a carefully engineered user interface that makes it easy to learn and use. Finally, a number of specialty characteristics have been built into SMART which allow it to be used efficiently as a front end geometry processor for other analysis packages. EASIE provides a set of interactive utilities that simplify the task of building and executing computer aided design systems consisting of diverse, stand-alone, analysis codes. Resulting in a streamlining of the exchange of data between programs reducing errors and improving the efficiency. EASIE provides both a methodology and a collection of software tools to ease the task of coordinating engineering design and analysis codes.

  5. 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…

  6. Photogrammetry and computer-aided piping design

    SciTech Connect

    Keneflick, J.F.; Chirillo, R.D.

    1985-02-18

    Three-dimensional measurements taken from photographs of a plant model can be digitized and linked with computer-aided piping design. This can short-cut the design and construction of new plants and expedite repair and retrofitting projects. Some designers bridge the gap between model and computer by digitizing from orthographic prints obtained via orthography or the laser scanning of model sections. Such valve or fitting then processed is described in this paper. The marriage of photogrammetry and computer-aided piping design can economically produce such numerical drawings.

  7. User interface for integrated computer aided design systems

    NASA Technical Reports Server (NTRS)

    Schwing, James L.

    1986-01-01

    The purpose was the development of a user interface and other appropriate tools to be used in Computer Aided Design systems which can integrate a wide variety of independently developed design and analysis tools. The interface was intended for the integration of programs to be used in the conceptual design of aerospace systems. A user's manual is included.

  8. Scaled Ellipses For Computer-Aided Design

    NASA Technical Reports Server (NTRS)

    Schembri, Anthony J.

    1990-01-01

    An addition to CAD-PACK, computer-aided design program, speeds preparation of iosmetric drawings, particularly cutaway views showing bores and threads. Consists of set of 50 scaled ellipses on detail pages of program. Designer selects ellipse, rotates it, and draws feature. Then erases reference lines on video screen.

  9. Computer-aided design for metabolic engineering.

    PubMed

    Fernández-Castané, Alfred; Fehér, Tamás; Carbonell, Pablo; Pauthenier, Cyrille; Faulon, Jean-Loup

    2014-12-20

    The development and application of biotechnology-based strategies has had a great socio-economical impact and is likely to play a crucial role in the foundation of more sustainable and efficient industrial processes. Within biotechnology, metabolic engineering aims at the directed improvement of cellular properties, often with the goal of synthesizing a target chemical compound. The use of computer-aided design (CAD) tools, along with the continuously emerging advanced genetic engineering techniques have allowed metabolic engineering to broaden and streamline the process of heterologous compound-production. In this work, we review the CAD tools available for metabolic engineering with an emphasis, on retrosynthesis methodologies. Recent advances in genetic engineering strategies for pathway implementation and optimization are also reviewed as well as a range of bionalytical tools to validate in silico predictions. A case study applying retrosynthesis is presented as an experimental verification of the output from Retropath, the first complete automated computational pipeline applicable to metabolic engineering. Applying this CAD pipeline, together with genetic reassembly and optimization of culture conditions led to improved production of the plant flavonoid pinocembrin. Coupling CAD tools with advanced genetic engineering strategies and bioprocess optimization is crucial for enhanced product yields and will be of great value for the development of non-natural products through sustainable biotechnological processes. PMID:24704607

  10. COMPUTER AIDED DESIGN OF DIFFUSED AERATION SYSTEMS

    EPA Science Inventory

    CADDAS (Computer Aided Design of Diffused Aeration Systems) is a microcomputer-based program that analyzes the cost and performance of diffused aeration used in activated sludge wastewater treatment systems. The program can analyze both coarse bubble and fine pore diffusers as we...

  11. Computer-Aided Design in Further Education.

    ERIC Educational Resources Information Center

    Ingham, Peter, Ed.

    This publication updates the 1982 occasional paper that was intended to foster staff awareness and assist colleges in Great Britain considering the use of computer-aided design (CAD) material in engineering courses. The paper begins by defining CAD and its place in the Integrated Business System with a brief discussion of the effect of CAD on the…

  12. Teaching Computer Aided Architectural Design at UCLA.

    ERIC Educational Resources Information Center

    Mitchell, William J.

    This brief overview includes a rationale for the program and describes course goals and objectives, curriculum content, teaching methods and materials, staffing, and problems of integrating computer aided design with traditional architectural curricula at the School of Architecture and Urban Planning at UCLA. A list of texts for use in teaching…

  13. A rule based computer aided design system

    NASA Technical Reports Server (NTRS)

    Premack, T.

    1986-01-01

    A Computer Aided Design (CAD) system is presented which supports the iterative process of design, the dimensional continuity between mating parts, and the hierarchical structure of the parts in their assembled configuration. Prolog, an interactive logic programming language, is used to represent and interpret the data base. The solid geometry representing the parts is defined in parameterized form using the swept volume method. The system is demonstrated with a design of a spring piston.

  14. CAE (computer-aided engineering) tools' limitations case study: An SSI (small scale integrated) design to an ASIC (application specific integrated circuit)

    SciTech Connect

    Everts, J.

    1989-01-01

    Every computer-aided engineering (CAE) tool has its limitations and shortcomings. Knowing where the pitfalls lie and how to get around them is extremely valuable. This paper takes a look at the problems and limitations encountered using the Daisy Systems suite of digital design tools (on a Logician 386 and a PKK386 MegaLogician, running DNIX 5.02A) to redesign a 169 small scale integrated (SSI) component design into an application specific integrated circuit (ASIC) gate array. Deficiencies were found in the libraries, ACE, MDLS, DTA, MCFS, and the Hotline support. Some solutions and workarounds to these deficiencies are presented.

  15. Engineering Technology Programs Courses Guide for Computer Aided Design and Computer Aided Manufacturing.

    ERIC Educational Resources Information Center

    Georgia Univ., Athens. Div. of Vocational Education.

    This guide describes the requirements for courses in computer-aided design and computer-aided manufacturing (CAD/CAM) that are part of engineering technology programs conducted in vocational-technical schools in Georgia. The guide is organized in five sections. The first section provides a rationale for occupations in design and in production,…

  16. 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.

  17. Software For Computer-Aided Design Of Control Systems

    NASA Technical Reports Server (NTRS)

    Wette, Matthew

    1994-01-01

    Computer Aided Engineering System (CAESY) software developed to provide means to evaluate methods for dealing with users' needs in computer-aided design of control systems. Interpreter program for performing engineering calculations. Incorporates features of both Ada and MATLAB. Designed to be flexible and powerful. Includes internally defined functions, procedures and provides for definition of functions and procedures by user. Written in C language.

  18. MLP Tools: a PyMOL plugin for using the molecular lipophilicity potential in computer-aided drug design.

    PubMed

    Oberhauser, Nils; Nurisso, Alessandra; Carrupt, Pierre-Alain

    2014-05-01

    The molecular lipophilicity potential (MLP) is a well-established method to calculate and visualize lipophilicity on molecules. We are here introducing a new computational tool named MLP Tools, written in the programming language Python, and conceived as a free plugin for the popular open source molecular viewer PyMOL. The plugin is divided into several sub-programs which allow the visualization of the MLP on molecular surfaces, as well as in three-dimensional space in order to analyze lipophilic properties of binding pockets. The sub-program Log MLP also implements the virtual log P which allows the prediction of the octanol/water partition coefficients on multiple three-dimensional conformations of the same molecule. An implementation on the recently introduced MLP GOLD procedure, improving the GOLD docking performance in hydrophobic pockets, is also part of the plugin. In this article, all functions of the MLP Tools will be described through a few chosen examples. PMID:24777339

  19. Computer-aided dispatching system design specification

    SciTech Connect

    Briggs, M.G.

    1997-12-16

    This document defines the performance requirements for a graphic display dispatching system to support Hanford Patrol Operations Center. This document reflects the as-built requirements for the system that was delivered by GTE Northwest, Inc. This system provided a commercial off-the-shelf computer-aided dispatching system and alarm monitoring system currently in operations at the Hanford Patrol Operations Center, Building 2721E. This system also provides alarm back-up capability for the Plutonium Finishing Plant (PFP).

  20. Computer-aided conceptual design of Air Cushion Vehicles

    NASA Astrophysics Data System (ADS)

    Band, E. G. U.; Lavis, D. R.

    This paper describes the development and use of a computer-aided design tool which has been used to explore preferred options for amphibious Air-Cushion Vehicle (ACV) and Surface-Effect Ship (SES) designs in support of U.S. Navy and U.S. Army programs. The tool, referred to as the ACV Design Synthesis Model (ADSM), is an interactive computer program which provides a description of feasible ACV or SES concepts that could be developed, by a competent design team, to perform the mission described by the input parameters. The paper discusses how the program was used to explore parametrically the design of a range of self-propelled hoverbarges to meet requirements of the U.S. Army Logistics Over the Shore (LOTS) phases of an amphibious landing. Examples of results are presented to illustrate the method used in determining design and performance trade-offs.

  1. Issues of a Computer-Aided Design of Hydraulic Jacks

    NASA Astrophysics Data System (ADS)

    Averchenkov, V. I.; Averchenkov, A. V.; Kolyakinand, V. V.; Orekhov, O. D.

    2016-04-01

    The article deals with the issues of a computer-aided design of hydraulic equipment, namely hydraulic jacks. Design principles of the hydraulic jack CAD system are described. In addition, the possibilities for the system improvement and expansion are considered.

  2. PLAID- A COMPUTER AIDED DESIGN SYSTEM

    NASA Technical Reports Server (NTRS)

    Brown, J. W.

    1994-01-01

    PLAID is a three-dimensional Computer Aided Design (CAD) system which enables the user to interactively construct, manipulate, and display sets of highly complex geometric models. PLAID was initially developed by NASA to assist in the design of Space Shuttle crewstation panels, and the detection of payload object collisions. It has evolved into a more general program for convenient use in many engineering applications. Special effort was made to incorporate CAD techniques and features which minimize the users workload in designing and managing PLAID models. PLAID consists of three major modules: the Primitive Object Generator (BUILD), the Composite Object Generator (COG), and the DISPLAY Processor. The BUILD module provides a means of constructing simple geometric objects called primitives. The primitives are created from polygons which are defined either explicitly by vertex coordinates, or graphically by use of terminal crosshairs or a digitizer. Solid objects are constructed by combining, rotating, or translating the polygons. Corner rounding, hole punching, milling, and contouring are special features available in BUILD. The COG module hierarchically organizes and manipulates primitives and other previously defined COG objects to form complex assemblies. The composite object is constructed by applying transformations to simpler objects. The transformations which can be applied are scalings, rotations, and translations. These transformations may be defined explicitly or defined graphically using the interactive COG commands. The DISPLAY module enables the user to view COG assemblies from arbitrary viewpoints (inside or outside the object) both in wireframe and hidden line renderings. The PLAID projection of a three-dimensional object can be either orthographic or with perspective. A conflict analysis option enables detection of spatial conflicts or collisions. DISPLAY provides camera functions to simulate a view of the model through different lenses. Other

  3. Computer-aided design development transition for IPAD environment

    NASA Technical Reports Server (NTRS)

    Owens, H. G.; Mock, W. D.; Mitchell, J. C.

    1980-01-01

    The relationship of federally sponsored computer-aided design/computer-aided manufacturing (CAD/CAM) programs to the aircraft life cycle design process, an overview of NAAD'S CAD development program, an evaluation of the CAD design process, a discussion of the current computing environment within which NAAD is developing its CAD system, some of the advantages/disadvantages of the NAAD-IPAD approach, and CAD developments during transition into the IPAD system are discussed.

  4. Computer-Aided Engineering of Batteries for Designing Better Li-Ion Batteries (Presentation)

    SciTech Connect

    Pesaran, A.; Kim, G. H.; Smith, K.; Lee, K. J.; Santhanagopalan, S.

    2012-02-01

    This presentation describes the current status of the DOE's Energy Storage R and D program, including modeling and design tools and the Computer-Aided Engineering for Automotive Batteries (CAEBAT) program.

  5. School District Uses Computer Aided Design and Drafting.

    ERIC Educational Resources Information Center

    Lorentz, Gordon S.

    1988-01-01

    Computer Aided Design and Drafting (CADD) programs are used to teach drafting at an Indiana high school. The school system's maintenance department shared use of the software and equipment to produce original drawings of school buildings. (MLF)

  6. Computer-aided software development process design

    NASA Technical Reports Server (NTRS)

    Lin, Chi Y.; Levary, Reuven R.

    1989-01-01

    The authors describe an intelligent tool designed to aid managers of software development projects in planning, managing, and controlling the development process of medium- to large-scale software projects. Its purpose is to reduce uncertainties in the budget, personnel, and schedule planning of software development projects. It is based on dynamic model for the software development and maintenance life-cycle process. This dynamic process is composed of a number of time-varying, interacting developmental phases, each characterized by its intended functions and requirements. System dynamics is used as a modeling methodology. The resulting Software LIfe-Cycle Simulator (SLICS) and the hybrid expert simulation system of which it is a subsystem are described.

  7. CAD/CAM (Computer Aided Design/Computer Aided Manufacture). A Brief Guide to Materials in the Library of Congress.

    ERIC Educational Resources Information Center

    Havas, George D.

    This brief guide to materials in the Library of Congress (LC) on computer aided design and/or computer aided manufacturing lists reference materials and other information sources under 13 headings: (1) brief introductions; (2) LC subject headings used for such materials; (3) textbooks; (4) additional titles; (5) glossaries and handbooks; (6)…

  8. Single-tooth dento-osseous osteotomy with a computer-aided design/computer-aided manufacturing surgical guide

    PubMed Central

    2016-01-01

    This clinical note introduces a method to assist surgeons in performing single-tooth dento-osseous osteotomy. For use in this method, a surgical guide was manufactured using computer-aided design/computer-aided manufacturing technology and was based on preoperative surgical simulation data. This method was highly conducive to successful single-tooth dento-osseous segmental osteotomy. PMID:27162756

  9. Critiquing the Computer-Aided Design of Dental Prostheses.

    ERIC Educational Resources Information Center

    Fitzpatrick, F. J.; And Others

    This paper describes RaPiD, a computer-aided assistant for the design of dental prostheses called removable partial dentures. The user manipulates icons directly to indicate the desired design solution to a given clinical situation. A developing design is represented as a logic database of components in a design; expert rules are applied as…

  10. Advances in computer-aided design and computer-aided manufacture technology.

    PubMed

    Calamia, J R

    1996-01-01

    Although the development of computer-aided design (CAD) and computer-aided manufacture (CAM) technology and the benefits of increased productivity became obvious in the automobile and aerospace industries in the 1970s, investigations of this technology's application in the field of dentistry did not begin until the 1980s. Only now are we beginning to see the fruits of this work with the commercial availability of some systems; the potential for this technology seems boundless. This article reviews the recent literature with emphasis on the period from June 1992 to May 1993. This review should familiarize the reader with some of the latest developments in this technology, including a brief description of some systems currently available and the clinical and economical rationale for their acceptance into the dental mainstream. This article concentrates on a particular system, the Cerec (Siemens/Pelton and Crane, Charlotte, NC) system, for three reasons: First, this system has been available since 1985 and, as a result, has a track record of almost 7 years of data. Most of the data have just recently been released and consequently, much of this year's literature on CAD-CAM is monopolized by studies using this system. Second, this system was developed as a mobile, affordable, direct chairside CAD-CAM restorative method. As such, it is of special interest to the patient, providing a one-visit restoration. Third, the author is currently engaged in research using this particular system and has a working knowledge of this system's capabilities. PMID:9462062

  11. USE OF COMPUTER-AIDED PROCESS ENGINEERING TOOL IN POLLUTION PREVENTION

    EPA Science Inventory

    Computer-Aided Process Engineering has become established in industry as a design tool. With the establishment of the CAPE-OPEN software specifications for process simulation environments. CAPE-OPEN provides a set of "middleware" standards that enable software developers to acces...

  12. Geometric modeling for computer aided design

    NASA Technical Reports Server (NTRS)

    Schwing, James L.

    1988-01-01

    Research focused on two major areas. The first effort addressed the design and implementation of a technique that allows for the visualization of the real time variation of physical properties. The second effort focused on the design and implementation of an on-line help system with components designed for both authors and users of help information.

  13. Interactive graphical computer-aided design system

    NASA Technical Reports Server (NTRS)

    Edge, T. M.

    1975-01-01

    System is used for design, layout, and modification of large-scale-integrated (LSI) metal-oxide semiconductor (MOS) arrays. System is structured around small computer which provides real-time support for graphics storage display unit with keyboard, slave display unit, hard copy unit, and graphics tablet for designer/computer interface.

  14. A digital patient for computer-aided prosthesis design

    PubMed Central

    Colombo, Giorgio; Facoetti, Giancarlo; Rizzi, Caterina

    2013-01-01

    This article concerns the design of lower limb prosthesis, both below and above knee. It describes a new computer-based design framework and a digital model of the patient around which the prosthesis is designed and tested in a completely virtual environment. The virtual model of the patient is the backbone of the whole system, and it is based on a biomechanical general-purpose model customized with the patient's characteristics (e.g. anthropometric measures). The software platform adopts computer-aided and knowledge-guided approaches with the goal of replacing the current development process, mainly hand made, with a virtual one. It provides the prosthetics with a set of tools to design, configure and test the prosthesis and comprehends two main environments: the prosthesis modelling laboratory and the virtual testing laboratory. The first permits the three-dimensional model of the prosthesis to be configured and generated, while the second allows the prosthetics to virtually set up the artificial leg and simulate the patient's postures and movements, validating its functionality and configuration. General architecture and modelling/simulation tools for the platform are described as well as main aspects and results of the experimentation. PMID:24427528

  15. Space systems computer-aided design technology

    NASA Technical Reports Server (NTRS)

    Garrett, L. B.

    1984-01-01

    The interactive Design and Evaluation of Advanced Spacecraft (IDEAS) system is described, together with planned capability increases in the IDEAS system. The system's disciplines consist of interactive graphics and interactive computing. A single user at an interactive terminal can create, design, analyze, and conduct parametric studies of earth-orbiting satellites, which represents a timely and cost-effective method during the conceptual design phase where various missions and spacecraft options require evaluation. Spacecraft concepts evaluated include microwave radiometer satellites, communication satellite systems, solar-powered lasers, power platforms, and orbiting space stations.

  16. Parallelization of ARC3D with Computer-Aided Tools

    NASA Technical Reports Server (NTRS)

    Jin, Haoqiang; Hribar, Michelle; Yan, Jerry; Saini, Subhash (Technical Monitor)

    1998-01-01

    A series of efforts have been devoted to investigating methods of porting and parallelizing applications quickly and efficiently for new architectures, such as the SCSI Origin 2000 and Cray T3E. This report presents the parallelization of a CFD application, ARC3D, using the computer-aided tools, Cesspools. Steps of parallelizing this code and requirements of achieving better performance are discussed. The generated parallel version has achieved reasonably well performance, for example, having a speedup of 30 for 36 Cray T3E processors. However, this performance could not be obtained without modification of the original serial code. It is suggested that in many cases improving serial code and performing necessary code transformations are important parts for the automated parallelization process although user intervention in many of these parts are still necessary. Nevertheless, development and improvement of useful software tools, such as Cesspools, can help trim down many tedious parallelization details and improve the processing efficiency.

  17. A review of computer-aided design/computer-aided manufacture techniques for removable denture fabrication

    PubMed Central

    Bilgin, Mehmet Selim; Baytaroğlu, Ebru Nur; Erdem, Ali; Dilber, Erhan

    2016-01-01

    The aim of this review was to investigate usage of computer-aided design/computer-aided manufacture (CAD/CAM) such as milling and rapid prototyping (RP) technologies for removable denture fabrication. An electronic search was conducted in the PubMed/MEDLINE, ScienceDirect, Google Scholar, and Web of Science databases. Databases were searched from 1987 to 2014. The search was performed using a variety of keywords including CAD/CAM, complete/partial dentures, RP, rapid manufacturing, digitally designed, milled, computerized, and machined. The identified developments (in chronological order), techniques, advantages, and disadvantages of CAD/CAM and RP for removable denture fabrication are summarized. Using a variety of keywords and aiming to find the topic, 78 publications were initially searched. For the main topic, the abstract of these 78 articles were scanned, and 52 publications were selected for reading in detail. Full-text of these articles was gained and searched in detail. Totally, 40 articles that discussed the techniques, advantages, and disadvantages of CAD/CAM and RP for removable denture fabrication and the articles were incorporated in this review. Totally, 16 of the papers summarized in the table. Following review of all relevant publications, it can be concluded that current innovations and technological developments of CAD/CAM and RP allow the digitally planning and manufacturing of removable dentures from start to finish. As a result according to the literature review CAD/CAM techniques and supportive maxillomandibular relationship transfer devices are growing fast. In the close future, fabricating removable dentures will become medical informatics instead of needing a technical staff and procedures. However the methods have several limitations for now. PMID:27095912

  18. A review of computer-aided design/computer-aided manufacture techniques for removable denture fabrication.

    PubMed

    Bilgin, Mehmet Selim; Baytaroğlu, Ebru Nur; Erdem, Ali; Dilber, Erhan

    2016-01-01

    The aim of this review was to investigate usage of computer-aided design/computer-aided manufacture (CAD/CAM) such as milling and rapid prototyping (RP) technologies for removable denture fabrication. An electronic search was conducted in the PubMed/MEDLINE, ScienceDirect, Google Scholar, and Web of Science databases. Databases were searched from 1987 to 2014. The search was performed using a variety of keywords including CAD/CAM, complete/partial dentures, RP, rapid manufacturing, digitally designed, milled, computerized, and machined. The identified developments (in chronological order), techniques, advantages, and disadvantages of CAD/CAM and RP for removable denture fabrication are summarized. Using a variety of keywords and aiming to find the topic, 78 publications were initially searched. For the main topic, the abstract of these 78 articles were scanned, and 52 publications were selected for reading in detail. Full-text of these articles was gained and searched in detail. Totally, 40 articles that discussed the techniques, advantages, and disadvantages of CAD/CAM and RP for removable denture fabrication and the articles were incorporated in this review. Totally, 16 of the papers summarized in the table. Following review of all relevant publications, it can be concluded that current innovations and technological developments of CAD/CAM and RP allow the digitally planning and manufacturing of removable dentures from start to finish. As a result according to the literature review CAD/CAM techniques and supportive maxillomandibular relationship transfer devices are growing fast. In the close future, fabricating removable dentures will become medical informatics instead of needing a technical staff and procedures. However the methods have several limitations for now. PMID:27095912

  19. Computer-aided design and computer science technology

    NASA Technical Reports Server (NTRS)

    Fulton, R. E.; Voigt, S. J.

    1976-01-01

    A description is presented of computer-aided design requirements and the resulting computer science advances needed to support aerospace design. The aerospace design environment is examined, taking into account problems of data handling and aspects of computer hardware and software. The interactive terminal is normally the primary interface between the computer system and the engineering designer. Attention is given to user aids, interactive design, interactive computations, the characteristics of design information, data management requirements, hardware advancements, and computer science developments.

  20. Computer Aided Design in the Classroom.

    ERIC Educational Resources Information Center

    Duelm, Brian Lee

    Estimates calling for 1.2 million computer-assisted design (CAD) operator positions to be available by 1990 have prompted educational institutions throughout the country to incorporate instruction in CAD into their industrial arts curricula. Therefore, the question for schools is not whether to buy but rather what to buy. An effective strategy for…

  1. Computer-aided surface representation and design

    NASA Technical Reports Server (NTRS)

    Barnhill, R. E.

    1984-01-01

    New methods for representing and approximating three and four dimensional surfaces were created. These schemes are the core of our forthcoming Surface Software Package. Surfaces are understood adequately only through the use of dynamic computer graphics; therefore, graphics capability is also included. The numerous applications of surface methods include modeling physical phenomena (e.g., combustion) and designing objects (e.g., airplanes and cars).

  2. Computer aided design study of hypermixing nozzles

    NASA Technical Reports Server (NTRS)

    Mefferd, L. A.; Bevilacqua, P. M.

    1979-01-01

    The development of a nozzle which combines the hypermixing and lobe mechanisms to achieve further increases in jet entrainment and ejector performance is investigated. A computer program which incorporates a two equation turbulence model and is used to predict and compare the evolution of jets from various nozzle designs is discussed. Increasing the length of the nozzle lobes and an alternating lobe nozzle are a methods examined for increasing the entrainment rate.

  3. Advances in computer-aided design and computer-aided manufacture technology.

    PubMed

    Calamia, J R

    1994-01-01

    Although the development of computer-aided design (CAD) and computer-aided manufacture (CAM) technology and the benefits of increased productivity became obvious in the automobile and aerospace industries in the 1970s, investigations of this technology's application in the field of dentistry did not begin until the 1980s. Only now are we beginning to see the fruits of this work with the commercial availability of some systems; the potential for this technology seems boundless. This article reviews the recent literature with emphasis on the period from June 1992 to May 1993. This review should familiarize the reader with some of the latest developments in this technology, including a brief description of some systems currently available and the clinical and economical rationale for their acceptance into the dental mainstream. This article concentrates on a particular system, the Cerec (Siemens/Pelton and Crane, Charlotte, NC) system, for three reasons: first, this system has been available since 1985 and, as a result, has a track record of almost 7 years of data. Most of the data have just recently been released and consequently, much of this year's literature on CAD-CAM is monopolized by studies using this system. Second, this system was developed as a mobile, affordable, direct chairside CAD-CAM restorative method. As such, it is of special interest to the dentist who will offer this new technology directly to the patient, providing a one-visit restoration. Third, the author is currently engaged in research using this particular system and has a working knowledge of this system's capabilities. PMID:8032444

  4. An Elective Course on Computer-Aided Process Design.

    ERIC Educational Resources Information Center

    Sommerfeld, Jude T.

    1979-01-01

    Describes an undergraduate chemical engineering course which has been offered at the Georgia Institute of Technology. The objectives, structure, instructional materials and content of this course, which emphasizes the structure and usage of computer-aided design systems, are also included. (HM)

  5. National Occupational Skill Standards. CADD: Computer Aided Drafting and Design.

    ERIC Educational Resources Information Center

    National Coalition for Advanced Manufacturing, Washington, DC.

    This document identifies computer-aided drafting and design (CADD) skills that companies require of training programs and future employees. The information was developed by two committees of technically knowledgeable CADD users from across the United States and validated by several hundred other CADD users. The skills are aimed at a beginner CADD…

  6. Current insights into computer-aided immunotherapeutic design strategies.

    PubMed

    Cai, Zhi; Zhang, Guoyin; Zhang, Xuejin; Liu, Yan; Fu, Xiaojing

    2015-09-01

    Drug designing costs as well as design of immunotherapeutic agents could be nearly halved through the involvement of computer-aided drug designing methods in discovery and research. The inter-disciplinary, time-, and money-consuming process of drug discovery is amended by the development of drug designing, the technique of creating or finding a molecule that can render stimulatory or inhibitory activity upon various biological organisms. Meanwhile, the advancements made within this scientific domain in the last couple of decades have significantly modified and affected the way new bioactive molecules have been produced by the pharmaceutical industry. In this regard, improvements made in hardware solutions and computational techniques along with their efficient integration with biological processes have revolutionized the in silico methods in speeding up the lead identification and optimization processes. In this review, we will discuss various methods of recent computer-aided drug designing techniques that forms the basis of modern day drug discovery projects. PMID:26091813

  7. Current topics in computer-aided drug design.

    PubMed

    Taft, Carlton A; Da Silva, Vinicius Barreto; Da Silva, Carlos Henrique Tomich De Paula

    2008-03-01

    The addition of computer-aided drug design (CADD) technologies to the research and drug discovery approaches could lead to a reduction of up to 50% in the cost of drug design. Designing a drug is the process of finding or creating a molecule which has a specific activity on a biological organism. Development and drug discovery is a time-consuming, expensive, and interdisciplinary process whereas scientific advancements during the past two decades have altered the way pharmaceutical research produces new bioactive molecules. Advances in computational techniques and hardware solutions have enabled in silico methods to speed up lead optimization and identification. We will review current topics in computer-aided molecular design underscoring some of the most recent approaches and interdisciplinary processes. We will discuss some of the most efficient pathways and design. PMID:18214973

  8. Computer aided systems human engineering: A hypermedia tool

    NASA Technical Reports Server (NTRS)

    Boff, Kenneth R.; Monk, Donald L.; Cody, William J.

    1992-01-01

    The Computer Aided Systems Human Engineering (CASHE) system, Version 1.0, is a multimedia ergonomics database on CD-ROM for the Apple Macintosh II computer, being developed for use by human system designers, educators, and researchers. It will initially be available on CD-ROM and will allow users to access ergonomics data and models stored electronically as text, graphics, and audio. The CASHE CD-ROM, Version 1.0 will contain the Boff and Lincoln (1988) Engineering Data Compendium, MIL-STD-1472D and a unique, interactive simulation capability, the Perception and Performance Prototyper. Its features also include a specialized data retrieval, scaling, and analysis capability and the state of the art in information retrieval, browsing, and navigation.

  9. Computer-Aided Drug Discovery and Design Targeting Ion Channels.

    PubMed

    Zhang, Qiansen; Gao, Zhaobing; Yang, Huaiyu

    2016-01-01

    Ion channels are widely expressed in living cells and play critical roles in various cellular biological functions. Dysfunctional ion channels can cause a variety of diseases, making ion channels attractive targets for drug discovery. Computational approaches, such as molecular docking and molecular dynamic simulations, provide economic and efficient tools for finding modulators of ion channels and for elucidating the action mechanisms of small molecules. In this review, we focus primarily on four types of ion channels (voltage-gated, ligand-gated, acid-sensing, and virus matrix 2 ion channels). The current advancements in computer-aided drug discovery and design targeting ion channels are summarized. First, ligand-based studies for drug design are briefly outlined. Then, we focus on the structurebased studies targeting pore domains, endogenous binding sites and allosteric sites of ion channels. Moreover, we also review the contribution of computational methods to the field of ligand binding and unbinding pathways of ion channels. Finally, we propose future developments for the field. PMID:26975507

  10. Computer-aided design of flight control systems

    NASA Technical Reports Server (NTRS)

    Stengel, Robert F.; Sircar, Subrata

    1991-01-01

    A computer program is presented for facilitating the development and assessment of flight control systems, and application to a control design is discussed. The program is a computer-aided control-system design program based on direct digital synthesis of a proportional-integral-filter controller with scheduled linear-quadratic-Gaussian gains and command generator tracking of pilot inputs. The FlightCAD system concentrates on aircraft dynamics, flight-control systems, stability and performance, and has practical engineering applications.

  11. Computer-aided design of polymers and composites

    NASA Technical Reports Server (NTRS)

    Kaelble, D. H.

    1985-01-01

    This book on computer-aided design of polymers and composites introduces and discusses the subject from the viewpoint of atomic and molecular models. Thus, the origins of stiffness, strength, extensibility, and fracture toughness in composite materials can be analyzed directly in terms of chemical composition and molecular structure. Aspects of polymer composite reliability are considered along with characterization techniques for composite reliability, relations between atomic and molecular properties, computer aided design and manufacture, polymer CAD/CAM models, and composite CAD/CAM models. Attention is given to multiphase structural adhesives, fibrous composite reliability, metal joint reliability, polymer physical states and transitions, chemical quality assurance, processability testing, cure monitoring and management, nondestructive evaluation (NDE), surface NDE, elementary properties, ionic-covalent bonding, molecular analysis, acid-base interactions, the manufacturing science, and peel mechanics.

  12. A computer aided design procedure for generating gear teeth

    NASA Technical Reports Server (NTRS)

    Chang, S. H.; Huston, R. L.; Coy, J. J.

    1984-01-01

    A procedure for computer aided design (CAD) of gear teeth is presented. It is developed for generated teeth fabricated by a hob cutter or a shaper. It provides a means for analytically and numerically determining the tooth profile, given the cutter profile. An illustrative example with involute tooth profiles is given. Application with non-standard profiles and with bevel, spiral bevel, and hypoid gears is discussed.

  13. Computer-Aided Design of a Sulfate Encapsulating Receptor

    SciTech Connect

    Custelcean, Radu; Bosano, Jerome J; Bonnesen, Peter V; Kertesz, Vilmos; Hay, Benjamin

    2009-01-01

    A promising new approach towards more efficient self-assembled cage receptors through computer-aided design is demonstrated. The resulting M{sub 4}L{sub 6} tetrahedral cage, internally functionalized with accurately positioned urea hydrogen-bonding groups (see structure; yellow: predicted, blue: experimental, space-filling: SO{sub 4}{sup 2-}), proved to be a remarkably strong sulfate receptor in water.

  14. Computer-Aided Design Of Sheet-Material Parts

    NASA Technical Reports Server (NTRS)

    Gilbert, Jeffrey L.; Paternoster, Vincent Y.; Levitt, Maureen L.; Osterloh, Mark R.

    1991-01-01

    Computer-aided-design system partly automates tedious process of designing and guiding assembly of small pieces of flat sheet material into large surfaces that approximate smoothly curved surfaces having complicated three-dimensional shapes. Capability provides for flexibility enabling designer to assess quickly and easily effects of changes in design in making engineering compromises among various sizes and shapes. Saves time and money in both design and fabrication. Used in rocket-engine application and other applications requiring design of sheet-material parts.

  15. SNL Mechanical Computer Aided Design (MCAD) guide 2007.

    SciTech Connect

    Moore, Brandon; Pollice, Stephanie L.; Martinez, Jack R.

    2007-12-01

    This document is considered a mechanical design best-practice guide to new and experienced designers alike. The contents consist of topics related to using Computer Aided Design (CAD) software, performing basic analyses, and using configuration management. The details specific to a particular topic have been leveraged against existing Product Realization Standard (PRS) and Technical Business Practice (TBP) requirements while maintaining alignment with sound engineering and design practices. This document is to be considered dynamic in that subsequent updates will be reflected in the main title, and each update will be published on an annual basis.

  16. Computer aided design of multi-phase switched reluctance motor

    NASA Astrophysics Data System (ADS)

    Sheth, N. K.; Rajagopal, K. R.

    2005-05-01

    In this paper, a comprehensive computer-aided design (CAD) procedure of multiphase switched reluctance motor (SRM) is presented. Better approach for calculation of the outer dimensions, phase inductance, flux linkage and losses, and also a different concept for calculating the average torque of the motor are incorporated in the CAD program. The average torque is calculated based on the most effective 15° (for 8/6 SRM) of the static torque profile of the motor. A sample design of a 5hp SRM is presented in detail and the design is validated by conducting a two-dimensional finite element analysis of the motor.

  17. Computer-aided structural design of a lunar radio telescope

    NASA Technical Reports Server (NTRS)

    Akgul, Ferhat; Gerstle, Walter H.; Johnson, Stewart W.

    1990-01-01

    This paper describes a computer-aided structural design of the main reflector of a fully steerable radio telescope to be located (in the 21st century) on the moon, and presents the results of the structural analysis of the reflector. The reflector is a paraboloid with a surface area of 12,660 sq m and a focal ratio of 0.42. The reflector's surface will be covered by a 5.08 cm-thick sandwich panel made of thin-walled aluminum cells filled with low-density foam. The low weight of the design will be achieved by using graphite-epoxy as the structural material.

  18. Improving radiation survey data using CADD/CAE (computer-aided design and drafting computer-aided engineering)

    SciTech Connect

    Palau, G.L.; Tarpinian, J.E.

    1987-01-01

    A new application of computer-aided design and drafting (CADD) and computer-aided engineering (CAE) at the Three Mile Island Unit 2 (TMI-2) cleanup is improving the quality of radiation survey data taken in the plant. The use of CADD/CAE-generated survey maps has increased both the accuracy of survey data and the capability to perform analyses with these data. In addition, health physics technician manhours and radiation exposure can be reduced in situations where the CADD/CAE-generated drawings are used for survey mapping.

  19. Computer aided design and analysis of gear tooth geometry

    NASA Technical Reports Server (NTRS)

    Chang, S. H.; Huston, R. L.

    1987-01-01

    A simulation method for gear hobbing and shaping of straight and spiral bevel gears is presented. The method is based upon an enveloping theory for gear tooth profile generation. The procedure is applicable in the computer aided design of standard and nonstandard tooth forms. An inverse procedure for finding a conjugate gear tooth profile is presented for arbitrary cutter geometry. The kinematic relations for the tooth surfaces of straight and spiral bevel gears are proposed. The tooth surface equations for these gears are formulated in a manner suitable for their automated numerical development and solution.

  20. Computer aided design of bevel gear tooth surfaces

    NASA Technical Reports Server (NTRS)

    Chang, S. H.; Huston, R. L.; Coy, J. J.

    1989-01-01

    This paper presents a computer-aided design procedure for generating bevel gears. The development is based on examining a perfectly plastic, cone-shaped gear blank rolling over a cutting tooth on a plane crown rack. The resulting impression on the plastic gear blank is the envelope of the cutting tooth. This impression and envelope thus form a conjugate tooth surface. Equations are presented for the locus of points on the tooth surface. The same procedures are then extended to simulate the generation of a spiral bevel gear. The corresponding governing equations are presented.

  1. Computer-aided design of bevel gear tooth surfaces

    NASA Technical Reports Server (NTRS)

    Shuo, Hung Chang; Huston, Ronald L.; Coy, John J.

    1989-01-01

    This paper presents a computer-aided design procedure for generating bevel gears. The development is based on examining a perfectly plastic, cone-shaped gear blank rolling over a cutting tooth on a plane crown rack. The resulting impression on the plastic gear blank is the envelope of the cutting tooth. This impression and envelope thus form a conjugate tooth surface. Equations are presented for the locus of points on the tooth surface. The same procedures are then extended to simulate the generation of a spiral bevel gear. The corresponding governing equations are presented.

  2. The Computer Aided Aircraft-design Package (CAAP)

    NASA Technical Reports Server (NTRS)

    Yalif, Guy U.

    1994-01-01

    The preliminary design of an aircraft is a complex, labor-intensive, and creative process. Since the 1970's, many computer programs have been written to help automate preliminary airplane design. Time and resource analyses have identified, 'a substantial decrease in project duration with the introduction of an automated design capability'. Proof-of-concept studies have been completed which establish 'a foundation for a computer-based airframe design capability', Unfortunately, today's design codes exist in many different languages on many, often expensive, hardware platforms. Through the use of a module-based system architecture, the Computer aided Aircraft-design Package (CAAP) will eventually bring together many of the most useful features of existing programs. Through the use of an expert system, it will add an additional feature that could be described as indispensable to entry level engineers and students: the incorporation of 'expert' knowledge into the automated design process.

  3. The ergonomics of computer aided design within advanced manufacturing technology.

    PubMed

    John, P A

    1988-03-01

    Many manufacturing companies have now awakened to the significance of computer aided design (CAD), although the majority of them have only been able to purchase computerised draughting systems of which only a subset produce direct manufacturing data. Such companies are moving steadily towards the concept of computer integrated manufacture (CIM), and this demands CAD to address more than draughting. CAD architects are thus having to rethink the basic specification of such systems, although they typically suffer from an insufficient understanding of the design task and have consequently been working with inadequate specifications. It is at this fundamental level that ergonomics has much to offer, making its contribution by encouraging user-centred design. The discussion considers the relationships between CAD and: the design task; the organisation and people; creativity; and artificial intelligence. It finishes with a summary of the contribution of ergonomics. PMID:15676646

  4. Evolution of Geometric Sensitivity Derivatives from Computer Aided Design Models

    NASA Technical Reports Server (NTRS)

    Jones, William T.; Lazzara, David; Haimes, Robert

    2010-01-01

    The generation of design parameter sensitivity derivatives is required for gradient-based optimization. Such sensitivity derivatives are elusive at best when working with geometry defined within the solid modeling context of Computer-Aided Design (CAD) systems. Solid modeling CAD systems are often proprietary and always complex, thereby necessitating ad hoc procedures to infer parameter sensitivity. A new perspective is presented that makes direct use of the hierarchical associativity of CAD features to trace their evolution and thereby track design parameter sensitivity. In contrast to ad hoc methods, this method provides a more concise procedure following the model design intent and determining the sensitivity of CAD geometry directly to its respective defining parameters.

  5. Computer aided microbial safety design of food processes.

    PubMed

    Schellekens, M; Martens, T; Roberts, T A; Mackey, B M; Nicolaï, B M; Van Impe, J F; De Baerdemaeker, J

    1994-12-01

    To reduce the time required for product development, to avoid expensive experimental tests, and to quantify safety risks for fresh products and the consequence of processing there is a growing interest in computer aided food process design. This paper discusses the application of hybrid object-oriented and rule-based expert system technology to represent the data and knowledge of microbial experts and food engineers. Finite element models for heat transfer calculation routines, microbial growth and inactivation models and texture kinetics are combined with food composition data, thermophysical properties, process steps and expert knowledge on type and quantity of microbial contamination. A prototype system has been developed to evaluate changes in food composition, process steps and process parameters on microbiological safety and textual quality of foods. PMID:7703003

  6. Quicklist: The basis for a computer aided logic design system

    NASA Technical Reports Server (NTRS)

    Lushbaugh, W. A.

    1980-01-01

    Quicklist, a preprocessor for an existing wire list program that cuts the description of the wire list by about 67 percent over previous methods, is described. Quicklist uses two different methods to shorten the input data. The first of these is the use of parentheses to allow a compact way of describing signal names which increment (or decrement) by one, i.e., typical signal names in a bus. The other method used is the equal sign. Using this symbol in a signal list says that the rest of the signals on that chip are the same as those on the previous chip described. Quicklist is intended to be the basis of a computer aided logic design system.

  7. From paper drawings to computer-aided design

    NASA Astrophysics Data System (ADS)

    Karima, M.; Sadhal, K. S.; McNeil, T. O.

    1985-02-01

    The benefits of a fully integrated computer-aided design and drafting system (CADDS) database are today very well accepted by industry, and major engineering companies implementing CADDS are confronted with the gigantic task of entering the existing multidisciplinary engineering information into the CADDS database. The present investigation is concerned with the findings of a feasibility study which had been conducted by a Canadian company to explore data capture on engineering drawings. A review of the state of the art in digitization is presented, and attention is given to specific problems arising in the case of the Canadian company. It is found that substantial advancements have been made toward the automatic 'reading' of existing drawings on paper media. However, no system exists currently which fully automates the data capturing process in the engineering environment and generates intelligent databases for use by CADD systems. Suitable approaches for 'data capture' under the given conditions are discussed.

  8. Application of fuzzy logic in computer-aided design of digital systems

    NASA Astrophysics Data System (ADS)

    Shragowitz, Eugene B.; Lee, Jun-Yong; Kang, Eric Q.

    1996-06-01

    Application of fuzzy logic structures in computer-aided design (CAD) of electronic systems substantially improves quality of design solutions by providing designers with flexibility in formulating goals and selecting trade-offs. In addition, the following aspects of a design process are positively impacted by application of fuzzy logic: utilization of domain knowledge, interpretation of uncertainties in design data, and adaptation of design algorithms. We successfully applied fuzzy logic structures in conjunction with constructive and iterative algorithms for selecting of design solutions for different stages of the design process. We also introduced a fuzzy logic software development tool to be used in CAD applications.

  9. Building a Better Bibliography: Computer-Aided Research Tools.

    ERIC Educational Resources Information Center

    Bloomfield, Elizabeth

    1989-01-01

    Describes a project at the University of Guelph (Ontario) that combined both bibliographical and archival references in one large machine readable database to facilitate local history research. The description covers research tool creation, planning activities, system design, the database management system used, material selection, record…

  10. Assessment of Chair-side Computer-Aided Design and Computer-Aided Manufacturing Restorations: A Review of the Literature

    PubMed Central

    Baroudi, Kusai; Ibraheem, Shukran Nasser

    2015-01-01

    Background: This paper aimed to evaluate the application of computer-aided design and computer-aided manufacturing (CAD-CAM) technology and the factors that affect the survival of restorations. Materials and Methods: A thorough literature search using PubMed, Medline, Embase, Science Direct, Wiley Online Library and Grey literature were performed from the year 2004 up to June 2014. Only relevant research was considered. Results: The use of chair-side CAD/CAM systems is promising in all dental branches in terms of minimizing time and effort made by dentists, technicians and patients for restoring and maintaining patient oral function and aesthetic, while providing high quality outcome. Conclusion: The way of producing and placing the restorations made with the chair-side CAD/CAM (CEREC and E4D) devices is better than restorations made by conventional laboratory procedures. PMID:25954082

  11. Computer-aided design of antenna structures and components

    NASA Technical Reports Server (NTRS)

    Levy, R.

    1976-01-01

    This paper discusses computer-aided design procedures for antenna reflector structures and related components. The primary design aid is a computer program that establishes cross sectional sizes of the structural members by an optimality criterion. Alternative types of deflection-dependent objectives can be selected for designs subject to constraints on structure weight. The computer program has a special-purpose formulation to design structures of the type frequently used for antenna construction. These structures, in common with many in other areas of application, are represented by analytical models that employ only the three translational degrees of freedom at each node. The special-purpose construction of the program, however, permits coding and data management simplifications that provide advantages in problem size and execution speed. Size and speed are essentially governed by the requirements of structural analysis and are relatively unaffected by the added requirements of design. Computation times to execute several design/analysis cycles are comparable to the times required by general-purpose programs for a single analysis cycle. Examples in the paper illustrate effective design improvement for structures with several thousand degrees of freedom and within reasonable computing times.

  12. The application of computer-aided technologies in automotive styling design

    NASA Astrophysics Data System (ADS)

    Zheng, Ze-feng; Zhang, Ji; Zheng, Ying

    2012-04-01

    In automotive industry, outline design is its life and creative design is its soul indeed. Computer-aided technology has been widely used in the automotive industry and more and more attention has been paid. This paper chiefly introduce the application of computer-aided technologies including CAD, CAM and CAE, analyses the process of automotive structural design and describe the development tendency of computer-aided design.

  13. Computer aided design of computer generated holograms for electron beam fabrication.

    PubMed

    Urquhart, K S; Lee, S H; Guest, C C; Feldman, M R; Farhoosh, H

    1989-08-15

    Computer Aided Design (CAD) systems that have been developed for electrical and mechanical design tasks are also effective tools for the process of designing Computer Generated Holograms (CGHs), particularly when these holograms are to be fabricated using electron beam lithography. CAD workstations provide efficient and convenient means of computing, storing, displaying, and preparing for fabrication many of the features that are common to CGH designs. Experience gained in the process of designing CGHs with various types of encoding methods is presented. Suggestions are made so that future workstations may further accommodate the CGH design process. PMID:20555710

  14. Computer Aided Design of Computer Generated Holograms for electron beam fabrication

    NASA Technical Reports Server (NTRS)

    Urquhart, Kristopher S.; Lee, Sing H.; Guest, Clark C.; Feldman, Michael R.; Farhoosh, Hamid

    1989-01-01

    Computer Aided Design (CAD) systems that have been developed for electrical and mechanical design tasks are also effective tools for the process of designing Computer Generated Holograms (CGHs), particularly when these holograms are to be fabricated using electron beam lithography. CAD workstations provide efficient and convenient means of computing, storing, displaying, and preparing for fabrication many of the features that are common to CGH designs. Experience gained in the process of designing CGHs with various types of encoding methods is presented. Suggestions are made so that future workstations may further accommodate the CGH design process.

  15. A machine learning approach to computer-aided molecular design.

    PubMed

    Bolis, G; Di Pace, L; Fabrocini, F

    1991-12-01

    Preliminary results of a machine learning application concerning computer-aided molecular design applied to drug discovery are presented. The artificial intelligence techniques of machine learning use a sample of active and inactive compounds, which is viewed as a set of positive and negative examples, to allow the induction of a molecular model characterizing the interaction between the compounds and a target molecule. The algorithm is based on a twofold phase. In the first one--the specialization step--the program identifies a number of active/inactive pairs of compounds which appear to be the most useful in order to make the learning process as effective as possible and generates a dictionary of molecular fragments, deemed to be responsible for the activity of the compounds. In the second phase--the generalization step--the fragments thus generated are combined and generalized in order to select the most plausible hypothesis with respect to the sample of compounds. A knowledge base concerning physical and chemical properties is utilized during the inductive process. PMID:1818094

  16. Computer-aided ergonomics: a case study of incorporating ergonomics analyses into workplace design.

    PubMed

    Feyen, R; Liu, Y; Chaffin, D; Jimmerson, G; Joseph, B

    2000-06-01

    One of the primary goals of computer-aided ergonomics is to develop software tools that allow ergonomics information to be accessed at the earliest stages of design. This case study discusses a PC-based software program that allows a designer to quantify a worker's biomechanical risk for injury based on a proposed workplace design. The program couples an established software tool for biomechanical analysis, the Three-Dimensional Static Strength Prediction Program (3DSSPP), with a widely used computer-aided design software package, AutoCAD. The use of this "3DSSPP/AutoCAD interface" in the proactive analysis of an automotive assembly task is described and the results compared with an independent assessment using observations of workers performing the same task. Both studies yield similar conclusions, suggesting that proactive use of software such as the 3DSSPP/AutoCAD interface may be a valid tool in evaluating proposed workplace designs. In this context, issues in the analysis of workplace designs regarding the use of supporting ergonomic tools, assumptions, and posture selection are discussed. PMID:10855452

  17. Computer Aided Design: Instructional Manual. The North Dakota High Technology Mobile Laboratory Project.

    ERIC Educational Resources Information Center

    Cheng, Wan-Lee

    This instructional manual contains 12 learning activity packets for use in a workshop in computer-aided design and drafting (CADD). The lessons cover the following topics: introduction to computer graphics and computer-aided design/drafting; coordinate systems; advance space graphics hardware configuration and basic features of the IBM PC…

  18. DEVELOPMENT AND USE OF COMPUTER-AIDED PROCESS ENGINEERING TOOLS FOR POLLUTION PREVENTION

    EPA Science Inventory

    The use of Computer-Aided Process Engineering (CAPE) and process simulation tools has become established industry practice to predict simulation software, new opportunities are available for the creation of a wide range of ancillary tools that can be used from within multiple sim...

  19. Fracture resistance of computer-aided design/computer-aided manufacturing-generated composite resin-based molar crowns.

    PubMed

    Harada, Akio; Nakamura, Keisuke; Kanno, Taro; Inagaki, Ryoichi; Örtengren, Ulf; Niwano, Yoshimi; Sasaki, Keiichi; Egusa, Hiroshi

    2015-04-01

    The aim of this study was to investigate whether different fabrication processes, such as the computer-aided design/computer-aided manufacturing (CAD/CAM) system or the manual build-up technique, affect the fracture resistance of composite resin-based crowns. Lava Ultimate (LU), Estenia C&B (EC&B), and lithium disilicate glass-ceramic IPS e.max press (EMP) were used. Four types of molar crowns were fabricated: CAD/CAM-generated composite resin-based crowns (LU crowns); manually built-up monolayer composite resin-based crowns (EC&B-monolayer crowns); manually built-up layered composite resin-based crowns (EC&B-layered crowns); and EMP crowns. Each type of crown was cemented to dies and the fracture resistance was tested. EC&B-layered crowns showed significantly lower fracture resistance compared with LU and EMP crowns, although there was no significant difference in flexural strength or fracture toughness between LU and EC&B materials. Micro-computed tomography and fractographic analysis showed that decreased strength probably resulted from internal voids in the EC&B-layered crowns introduced by the layering process. There was no significant difference in fracture resistance among LU, EC&B-monolayer, and EMP crowns. Both types of composite resin-based crowns showed fracture loads of >2000 N, which is higher than the molar bite force. Therefore, CAD/CAM-generated crowns, without internal defects, may be applied to molar regions with sufficient fracture resistance. PMID:25683749

  20. Costs incurred by applying computer-aided design/computer-aided manufacturing techniques for the reconstruction of maxillofacial defects.

    PubMed

    Rustemeyer, Jan; Melenberg, Alex; Sari-Rieger, Aynur

    2014-12-01

    This study aims to evaluate the additional costs incurred by using a computer-aided design/computer-aided manufacturing (CAD/CAM) technique for reconstructing maxillofacial defects by analyzing typical cases. The medical charts of 11 consecutive patients who were subjected to the CAD/CAM technique were considered, and invoices from the companies providing the CAD/CAM devices were reviewed for every case. The number of devices used was significantly correlated with cost (r = 0.880; p < 0.001). Significant differences in mean costs were found between cases in which prebent reconstruction plates were used (€3346.00 ± €29.00) and cases in which they were not (€2534.22 ± €264.48; p < 0.001). Significant differences were also obtained between the costs of two, three and four devices, even when ignoring the cost of reconstruction plates. Additional fees provided by statutory health insurance covered a mean of 171.5% ± 25.6% of the cost of the CAD/CAM devices. Since the additional fees provide financial compensation, we believe that the CAD/CAM technique is suited for wide application and not restricted to complex cases. Where additional fees/funds are not available, the CAD/CAM technique might be unprofitable, so the decision whether or not to use it remains a case-to-case decision with respect to cost versus benefit. PMID:25459375

  1. Laser imaging and computer-aided design and computer-aided manufacture in prosthetics and orthotics.

    PubMed

    Spaeth, John P

    2006-02-01

    Although Hanger Orthopedic Group, Inc., has been developing clinical protocols for its INSIGNIA scanner for more than 2 years, there are many applications that are currently in development and will be released over the next 2-year period after this publication. It is the goal of Hanger Orthopedic Group, Inc., to replace all plaster casting procedures with the laser scan and move toward a paperless environment where all images and documents are passed through its virtual network. INSIGNIA currently has five major production centers throughout the United States, which support more than 600 INSIGNIA certified clinicians. These clinicians staff more than 600 clinics in North America, all under the Hanger company name. The central fabrication service and the central design center processes hundreds of shapes per day (Fig. 27). So that any clinician in the field can use the expertise of the central designers and central fabricators to help with overflow or problems they might be having, the network that exists within Hanger is tied together and enhanced by INSIGNIA. Through virtual modification and centralization of these services, each patient receives the virtual collaboration of several clinicians with a total of years of experience. INSIGNIA has enhanced the patient experience. The enhancement is not only in removing the plaster from the process, but also in exposing each patient to the team of prosthetic experts working collaboratively behind the scenes. The rehabilitation industry continues to be bombarded with compliance paperwork and justifications. The INSIGNIA scan and resulting measurement reports give inherent strength to justifications based on volume change, surgical revisions, or tissue change. The files are kept in a data warehouse where they are vaulted and preserved presumably forever. Also, any of the shape graphics or measurement instruments can be printed into a discrete report that can become part of the patient's permanent record. Many physicians

  2. Rubber airplane: Constraint-based component-modeling for knowledge representation in computer-aided conceptual design

    NASA Technical Reports Server (NTRS)

    Kolb, Mark A.

    1990-01-01

    Viewgraphs on Rubber Airplane: Constraint-based Component-Modeling for Knowledge Representation in Computer Aided Conceptual Design are presented. Topics covered include: computer aided design; object oriented programming; airfoil design; surveillance aircraft; commercial aircraft; aircraft design; and launch vehicles.

  3. Enhancing Engineering Computer-Aided Design Education Using Lectures Recorded on the PC

    ERIC Educational Resources Information Center

    McGrann, Roy T. R.

    2006-01-01

    Computer-Aided Engineering (CAE) is a course that is required during the third year in the mechanical engineering curriculum at Binghamton University. The primary objective of the course is to educate students in the procedures of computer-aided engineering design. The solid modeling and analysis program Pro/Engineer[TM] (PTC[R]) is used as the…

  4. Teaching Computer-Aided Design of Fluid Flow and Heat Transfer Engineering Equipment.

    ERIC Educational Resources Information Center

    Gosman, A. D.; And Others

    1979-01-01

    Describes a teaching program for fluid mechanics and heat transfer which contains both computer aided learning (CAL) and computer aided design (CAD) components and argues that the understanding of the physical and numerical modeling taught in the CAL course is essential to the proper implementation of CAD. (Author/CMV)

  5. Micrometric precision of prosthetic dental crowns obtained by optical scanning and computer-aided designing/computer-aided manufacturing system

    NASA Astrophysics Data System (ADS)

    das Neves, Flávio Domingues; de Almeida Prado Naves Carneiro, Thiago; do Prado, Célio Jesus; Prudente, Marcel Santana; Zancopé, Karla; Davi, Letícia Resende; Mendonça, Gustavo; Soares, Carlos José

    2014-08-01

    The current study evaluated prosthetic dental crowns obtained by optical scanning and a computer-aided designing/computer-aided manufacturing system using micro-computed tomography to compare the marginal fit. The virtual models were obtained with four different scanning surfaces: typodont (T), regular impressions (RI), master casts (MC), and powdered master casts (PMC). Five virtual models were obtained for each group. For each model, a crown was designed on the software and milled from feldspathic ceramic blocks. Micro-CT images were obtained for marginal gap measurements and the data were statistically analyzed by one-way analysis of variance followed by Tukey's test. The mean vertical misfit was T=62.6±65.2 μm; MC=60.4±38.4 μm; PMC=58.1±38.0 μm, and RI=89.8±62.8 μm. Considering a percentage of vertical marginal gap of up to 75 μm, the results were T=71.5%, RI=49.2%, MC=69.6%, and PMC=71.2%. The percentages of horizontal overextension were T=8.5%, RI=0%, MC=0.8%, and PMC=3.8%. Based on the results, virtual model acquisition by scanning the typodont (simulated mouth) or MC, with or without powder, showed acceptable values for the marginal gap. The higher result of marginal gap of the RI group suggests that it is preferable to scan this directly from the mouth or from MC.

  6. Use Computer-Aided Tools to Parallelize Large CFD Applications

    NASA Technical Reports Server (NTRS)

    Jin, H.; Frumkin, M.; Yan, J.

    2000-01-01

    Porting applications to high performance parallel computers is always a challenging task. It is time consuming and costly. With rapid progressing in hardware architectures and increasing complexity of real applications in recent years, the problem becomes even more sever. Today, scalability and high performance are mostly involving handwritten parallel programs using message-passing libraries (e.g. MPI). However, this process is very difficult and often error-prone. The recent reemergence of shared memory parallel (SMP) architectures, such as the cache coherent Non-Uniform Memory Access (ccNUMA) architecture used in the SGI Origin 2000, show good prospects for scaling beyond hundreds of processors. Programming on an SMP is simplified by working in a globally accessible address space. The user can supply compiler directives, such as OpenMP, to parallelize the code. As an industry standard for portable implementation of parallel programs for SMPs, OpenMP is a set of compiler directives and callable runtime library routines that extend Fortran, C and C++ to express shared memory parallelism. It promises an incremental path for parallel conversion of existing software, as well as scalability and performance for a complete rewrite or an entirely new development. Perhaps the main disadvantage of programming with directives is that inserted directives may not necessarily enhance performance. In the worst cases, it can create erroneous results. While vendors have provided tools to perform error-checking and profiling, automation in directive insertion is very limited and often failed on large programs, primarily due to the lack of a thorough enough data dependence analysis. To overcome the deficiency, we have developed a toolkit, CAPO, to automatically insert OpenMP directives in Fortran programs and apply certain degrees of optimization. CAPO is aimed at taking advantage of detailed inter-procedural dependence analysis provided by CAPTools, developed by the University of

  7. COMPUTER AIDED SOLVENT DESIGN FOR POLLUTION PREVENTION - PARIS II (SYSTEMS ANALYSIS BRANCH, SUSTAINABLE TECHNOLOGY DIVISION, NRMRL)

    EPA Science Inventory

    This method was designed to facilitate the replacement of environmentally objectionable industrial solvents by using computer aided methods to design benign replacement solvents or solvent mixtures. The method generates a short list of recommended replacement solvents or mixtures...

  8. Accuracy of different types of computer-aided design/computer-aided manufacturing surgical guides for dental implant placement

    PubMed Central

    Geng, Wei; Liu, Changying; Su, Yucheng; Li, Jun; Zhou, Yanmin

    2015-01-01

    Purpose: To evaluate the clinical outcomes of implants placed using different types of computer-aided design/computer-aided manufacturing (CAD/CAM) surgical guides, including partially guided and totally guided templates, and determine the accuracy of these guides Materials and methods: In total, 111 implants were placed in 24 patients using CAD/CAM surgical guides. After implant insertion, the positions and angulations of the placed implants relative to those of the planned ones were determined using special software that matched pre- and postoperative computed tomography (CT) images, and deviations were calculated and compared between the different guides and templates. Results: The mean angular deviations were 1.72 ± 1.67 and 2.71 ± 2.58, the mean deviations in position at the neck were 0.27 ± 0.24 and 0.69 ± 0.66 mm, the mean deviations in position at the apex were 0.37 ± 0.35 and 0.94 ± 0.75 mm, and the mean depth deviations were 0.32 ± 0.32 and 0.51 ± 0.48 mm with tooth- and mucosa-supported stereolithographic guides, respectively (P < .05 for all). The mean distance deviations when partially guided (29 implants) and totally guided templates (30 implants) were used were 0.54 ± 0.50 mm and 0.89 ± 0.78 mm, respectively, at the neck and 1.10 ± 0.85 mm and 0.81 ± 0.64 mm, respectively, at the apex, with corresponding mean angular deviations of 2.56 ± 2.23° and 2.90 ± 3.0° (P > .05 for all). Conclusions: Tooth-supported surgical guides may be more accurate than mucosa-supported guides, while both partially and totally guided templates can simplify surgery and aid in optimal implant placement. PMID:26309497

  9. Custom-Made Computer-Aided-Design/Computer-Aided-Manufacturing Biphasic Calcium-Phosphate Scaffold for Augmentation of an Atrophic Mandibular Anterior Ridge.

    PubMed

    Mangano, Francesco Guido; Zecca, Piero Antonio; van Noort, Ric; Apresyan, Samvel; Iezzi, Giovanna; Piattelli, Adriano; Macchi, Aldo; Mangano, Carlo

    2015-01-01

    This report documents the clinical, radiographic, and histologic outcome of a custom-made computer-aided-design/computer-aided-manufactured (CAD/CAM) scaffold used for the alveolar ridge augmentation of a severely atrophic anterior mandible. Computed tomographic (CT) images of an atrophic anterior mandible were acquired and modified into a 3-dimensional (3D) reconstruction model; this was transferred to a CAD program, where a custom-made scaffold was designed. CAM software generated a set of tool-paths for the manufacture of the scaffold on a computer-numerical-control milling machine into the exact shape of the 3D design. A custom-made scaffold was milled from a synthetic micromacroporous biphasic calcium phosphate (BCP) block. The scaffold closely matched the shape of the defect: this helped to reduce the time for the surgery and contributed to good healing. One year later, newly formed and well-integrated bone was clinically available, and two implants (AnyRidge, MegaGen, Gyeongbuk, South Korea) were placed. The histologic samples retrieved from the implant sites revealed compact mature bone undergoing remodelling, marrow spaces, and newly formed trabecular bone surrounded by residual BCP particles. This study demonstrates that custom-made scaffolds can be fabricated by combining CT scans and CAD/CAM techniques. Further studies on a larger sample of patients are needed to confirm these results. PMID:26064701

  10. Custom-Made Computer-Aided-Design/Computer-Aided-Manufacturing Biphasic Calcium-Phosphate Scaffold for Augmentation of an Atrophic Mandibular Anterior Ridge

    PubMed Central

    Mangano, Francesco Guido; van Noort, Ric; Apresyan, Samvel; Piattelli, Adriano; Macchi, Aldo

    2015-01-01

    This report documents the clinical, radiographic, and histologic outcome of a custom-made computer-aided-design/computer-aided-manufactured (CAD/CAM) scaffold used for the alveolar ridge augmentation of a severely atrophic anterior mandible. Computed tomographic (CT) images of an atrophic anterior mandible were acquired and modified into a 3-dimensional (3D) reconstruction model; this was transferred to a CAD program, where a custom-made scaffold was designed. CAM software generated a set of tool-paths for the manufacture of the scaffold on a computer-numerical-control milling machine into the exact shape of the 3D design. A custom-made scaffold was milled from a synthetic micromacroporous biphasic calcium phosphate (BCP) block. The scaffold closely matched the shape of the defect: this helped to reduce the time for the surgery and contributed to good healing. One year later, newly formed and well-integrated bone was clinically available, and two implants (AnyRidge, MegaGen, Gyeongbuk, South Korea) were placed. The histologic samples retrieved from the implant sites revealed compact mature bone undergoing remodelling, marrow spaces, and newly formed trabecular bone surrounded by residual BCP particles. This study demonstrates that custom-made scaffolds can be fabricated by combining CT scans and CAD/CAM techniques. Further studies on a larger sample of patients are needed to confirm these results. PMID:26064701

  11. IDEAS: A multidisciplinary computer-aided conceptual design system for spacecraft

    NASA Technical Reports Server (NTRS)

    Ferebee, M. J., Jr.

    1984-01-01

    During the conceptual development of advanced aerospace vehicles, many compromises must be considered to balance economy and performance of the total system. Subsystem tradeoffs may need to be made in order to satisfy system-sensitive attributes. Due to the increasingly complex nature of aerospace systems, these trade studies have become more difficult and time-consuming to complete and involve interactions of ever-larger numbers of subsystems, components, and performance parameters. The current advances of computer-aided synthesis, modeling and analysis techniques have greatly helped in the evaluation of competing design concepts. Langley Research Center's Space Systems Division is currently engaged in trade studies for a variety of systems which include advanced ground-launched space transportation systems, space-based orbital transfer vehicles, large space antenna concepts and space stations. The need for engineering analysis tools to aid in the rapid synthesis and evaluation of spacecraft has led to the development of the Interactive Design and Evaluation of Advanced Spacecraft (IDEAS) computer-aided design system. The ADEAS system has been used to perform trade studies of competing technologies and requirements in order to pinpoint possible beneficial areas for research and development. IDEAS is presented as a multidisciplinary tool for the analysis of advanced space systems. Capabilities range from model generation and structural and thermal analysis to subsystem synthesis and performance analysis.

  12. Modeling And Simulation Of Bar Code Scanners Using Computer Aided Design Software

    NASA Astrophysics Data System (ADS)

    Hellekson, Ron; Campbell, Scott

    1988-06-01

    Many optical systems have demanding requirements to package the system in a small 3 dimensional space. The use of computer graphic tools can be a tremendous aid to the designer in analyzing the optical problems created by smaller and less costly systems. The Spectra Physics grocery store bar code scanner employs an especially complex 3 dimensional scan pattern to read bar code labels. By using a specially written program which interfaces with a computer aided design system, we have simulated many of the functions of this complex optical system. In this paper we will illustrate how a recent version of the scanner has been designed. We will discuss the use of computer graphics in the design process including interactive tweaking of the scan pattern, analysis of collected light, analysis of the scan pattern density, and analysis of the manufacturing tolerances used to build the scanner.

  13. Computer-aided Molecular Design of Compounds Targeting Histone Modifying Enzymes

    PubMed Central

    Andreoli, Federico; Del Rio, Alberto

    2015-01-01

    Growing evidences show that epigenetic mechanisms play crucial roles in the genesis and progression of many physiopathological processes. As a result, research in epigenetic grew at a fast pace in the last decade. In particular, the study of histone post-translational modifications encountered an extraordinary progression and many modifications have been characterized and associated to fundamental biological processes and pathological conditions. Histone modifications are the catalytic result of a large set of enzyme families that operate covalent modifications on specific residues at the histone tails. Taken together, these modifications elicit a complex and concerted processing that greatly contribute to the chromatin remodeling and may drive different pathological conditions, especially cancer. For this reason, several epigenetic targets are currently under validation for drug discovery purposes and different academic and industrial programs have been already launched to produce the first pre-clinical and clinical outcomes. In this scenario, computer-aided molecular design techniques are offering important tools, mainly as a consequence of the increasing structural information available for these targets. In this mini-review we will briefly discuss the most common types of known histone modifications and the corresponding operating enzymes by emphasizing the computer-aided molecular design approaches that can be of use to speed-up the efforts to generate new pharmaceutically relevant compounds. PMID:26082827

  14. Connectivity among computer-aided engineering methods, procedures, and tools used in developing the SSC collider magnets

    SciTech Connect

    Kallas, N.; Jalloh, A.R.

    1992-03-01

    The accomplishment of functional productivity for the computer aided engineering (CAE) environment at the magnet engineering department (ME) of the magnet systems divisions (MSD) at the Superconducting Super Collider Laboratory (SSCL) involves most of the basic aspects of information engineering. It is highly desirable to arrive at a software and hardware topology that offers total, two-way (back and forth), automatic and direct software and hardware connectivity among computer-aided design and drafting (CADD), analysis codes, and office automation tools applicable to the disciplines involved. This paper describes the components, data flow, and practices employed in the development of the CAE environment from a systems engineering aspect rather than from the analytical angle. When appropriate, references to case studies are made in order to demonstrate the connectivity of the techniques used.

  15. Computer aided design environment for the analysis and design of multi-body flexible structures

    NASA Technical Reports Server (NTRS)

    Ramakrishnan, Jayant V.; Singh, Ramen P.

    1989-01-01

    A computer aided design environment consisting of the programs NASTRAN, TREETOPS and MATLAB is presented in this paper. With links for data transfer between these programs, the integrated design of multi-body flexible structures is significantly enhanced. The CAD environment is used to model the Space Shuttle/Pinhole Occulater Facility. Then a controller is designed and evaluated in the nonlinear time history sense. Recent enhancements and ongoing research to add more capabilities are also described.

  16. Assess/Mitigate Risk through the Use of Computer-Aided Software Engineering (CASE) Tools

    NASA Technical Reports Server (NTRS)

    Aguilar, Michael L.

    2013-01-01

    The NASA Engineering and Safety Center (NESC) was requested to perform an independent assessment of the mitigation of the Constellation Program (CxP) Risk 4421 through the use of computer-aided software engineering (CASE) tools. With the cancellation of the CxP, the assessment goals were modified to capture lessons learned and best practices in the use of CASE tools. The assessment goal was to prepare the next program for the use of these CASE tools. The outcome of the assessment is contained in this document.

  17. Creating a strategic plan for configuration management using computer aided software engineering (CASE) tools

    SciTech Connect

    Smith, P.R.; Sarfaty, R.

    1993-05-01

    This paper provides guidance in the definition, documentation, measurement, enhancement of processes, and validation of a strategic plan for configuration management (CM). The approach and methodology used in establishing a strategic plan is the same for any enterprise, including the Department of Energy (DOE), commercial nuclear plants, the Department of Defense (DOD), or large industrial complexes. The principles and techniques presented are used world wide by some of the largest corporations. The authors used industry knowledge and the areas of their current employment to illustrate and provide examples. Developing a strategic configuration and information management plan for DOE Idaho Field Office (DOE-ID) facilities is discussed in this paper. A good knowledge of CM principles is the key to successful strategic planning. This paper will describe and define CM elements, and discuss how CM integrates the facility`s physical configuration, design basis, and documentation. The strategic plan does not need the support of a computer aided software engineering (CASE) tool. However, the use of the CASE tool provides a methodology for consistency in approach, graphics, and database capability combined to form an encyclopedia and a method of presentation that is easily understood and aids the process of reengineering. CASE tools have much more capability than those stated above. Some examples are supporting a joint application development group (JAD) to prepare a software functional specification document and, if necessary, provide the capability to automatically generate software application code. This paper briefly discusses characteristics and capabilities of two CASE tools that use different methodologies to generate similar deliverables.

  18. 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.

  19. Mandibular Reconstruction Using a Custom-Made Titanium Prosthesis: A Case Report on the Use of Virtual Surgical Planning and Computer-Aided Design/Computer-Aided Manufacturing.

    PubMed

    Ow, Andrew; Tan, Winston; Pienkowski, Lukasz

    2016-09-01

    The use of virtual surgical planning and computer-aided design/computer-aided manufacturing has been reported to enhance the planning for the reconstruction of mandibular continuity defects. This case report illustrates the use of this technology in the fabrication of a custom-made titanium prosthesis to restore a segmental mandibular defect. The design specifications and sequence of the custom-made titanium prosthesis are discussed. Although successful in this case, there are limitations in its application and case selection is of vital importance. PMID:27516841

  20. Harnessing Polypharmacology with Computer-Aided Drug Design and Systems Biology.

    PubMed

    Wathieu, Henri; Issa, Naiem T; Byers, Stephen W; Dakshanamurthy, Sivanesan

    2016-01-01

    The ascent of polypharmacology in drug development has many implications for disease therapy, most notably in the efforts of drug discovery, drug repositioning, precision medicine and combination therapy. The single- target approach to drug development has encountered difficulties in predicting drugs that are both clinically efficacious and avoid toxicity. By contrast, polypharmacology offers the possibility of a controlled distribution of effects on a biological system. This review addresses possibilities and bottlenecks in the efficient computational application of polypharmacology. The two major areas we address are the discovery and prediction of multiple protein targets using the tools of computer-aided drug design, and the use of these protein targets in predicting therapeutic potential in the context of biological networks. The successful application of polypharmacology to systems biology and pharmacology has the potential to markedly accelerate the pace of development of novel therapies for multiple diseases, and has implications for the intellectual property landscape, likely requiring targeted changes in patent law. PMID:26907947

  1. Creation of Anatomically Accurate Computer-Aided Design (CAD) Solid Models from Medical Images

    NASA Technical Reports Server (NTRS)

    Stewart, John E.; Graham, R. Scott; Samareh, Jamshid A.; Oberlander, Eric J.; Broaddus, William C.

    1999-01-01

    Most surgical instrumentation and implants used in the world today are designed with sophisticated Computer-Aided Design (CAD)/Computer-Aided Manufacturing (CAM) software. This software automates the mechanical development of a product from its conceptual design through manufacturing. CAD software also provides a means of manipulating solid models prior to Finite Element Modeling (FEM). Few surgical products are designed in conjunction with accurate CAD models of human anatomy because of the difficulty with which these models are created. We have developed a novel technique that creates anatomically accurate, patient specific CAD solids from medical images in a matter of minutes.

  2. Computer-aided designing of automatic process control systems for thermal power stations

    NASA Astrophysics Data System (ADS)

    Trofimov, A. V.

    2009-10-01

    The structure of modern microprocessor systems for automated control of technological processes at cogeneration stations is considered. Methods for computer-aided designing of the lower (sensors and actuators) and upper (cabinets of computerized automation equipment) levels of an automated process control system are proposed. The composition of project documents, the structures of a project database and database of a computer-aided design system, and the way they interact with one another in the course of developing the project of an automated process control system are described. Elements of the interface between a design engineer and computer program are shown.

  3. Hardware synthesis from DDL. [Digital Design Language for computer aided design and test of LSI

    NASA Technical Reports Server (NTRS)

    Shah, A. M.; Shiva, S. G.

    1981-01-01

    The details of the digital systems can be conveniently input into the design automation system by means of Hardware Description Languages (HDL). The Computer Aided Design and Test (CADAT) system at NASA MSFC is used for the LSI design. The Digital Design Language (DDL) has been selected as HDL for the CADAT System. DDL translator output can be used for the hardware implementation of the digital design. This paper addresses problems of selecting the standard cells from the CADAT standard cell library to realize the logic implied by the DDL description of the system.

  4. Computer-Aided Design Of Turbine Blades And Vanes

    NASA Technical Reports Server (NTRS)

    Hsu, Wayne Q.

    1988-01-01

    Quasi-three-dimensional method for determining aerothermodynamic configuration of turbine uses computer-interactive analysis and design and computer-interactive graphics. Design procedure executed rapidly so designer easily repeats it to arrive at best performance, size, structural integrity, and engine life. Sequence of events in aerothermodynamic analysis and design starts with engine-balance equations and ends with boundary-layer analysis and viscous-flow calculations. Analysis-and-design procedure interactive and iterative throughout.

  5. Experience gained at ZAO Ural Turbine Works with the use of computer-aided design systems

    NASA Astrophysics Data System (ADS)

    Kortenko, V. V.; Valamin, A. E.; Shanturov, D. N.; Sokolov, E. V.; Toibich, S. V.; Glushchenko, A. N.

    2008-08-01

    The results of work accomplished in the field of computer-aided design at ZAO Ural Turbine Works (UTZ) are presented. A concept is described following which the tasks for a specialist’s workstations being developed at the UTZ are solved. Results from solution of problems with the use of modern numerical simulation computer programs for analyzing gas dynamic processes, casting, welding, and strength of complex structures are given. An example is given to show efficient use of a computer-aided design system for shifting an enterprise to a modern level of automation.

  6. Human factors of intelligent computer aided display design

    NASA Technical Reports Server (NTRS)

    Hunt, R. M.

    1985-01-01

    Design concepts for a decision support system being studied at NASA Langley as an aid to visual display unit (VDU) designers are described. Ideally, human factors should be taken into account by VDU designers. In reality, although the human factors database on VDUs is small, such systems must be constantly developed. Human factors are therefore a secondary consideration. An expert system will thus serve mainly in an advisory capacity. Functions can include facilitating the design process by shortening the time to generate and alter drawings, enhancing the capability of breaking design requirements down into simpler functions, and providing visual displays equivalent to the final product. The VDU system could also discriminate, and display the difference, between designer decisions and machine inferences. The system could also aid in analyzing the effects of designer choices on future options and in ennunciating when there are data available on a design selections.

  7. Computer-aided design of stripline ferrite junction circulators

    NASA Technical Reports Server (NTRS)

    Uzdy, Z.

    1980-01-01

    A general design procedure is presented for stripline Y-junction circulators employing solid dielectric between ground planes. The resonator design and impedance matching are derived in a form suitable for computer evaluation. The procedure is applicable to cases where either the circulator bandwidth or the ground plane spacing is specified. An experimental S-band switching circulator design illustrates the technique.

  8. e-LEA3D: a computational-aided drug design web server

    PubMed Central

    Douguet, Dominique

    2010-01-01

    e-LEA3D web server integrates three complementary tools to perform computer-aided drug design based on molecular fragments. In drug discovery projects, there is a considerable interest in identifying novel and diverse molecular scaffolds to enhance chances of success. The de novo drug design tool is used to invent new ligands to optimize a user-specified scoring function. The composite scoring function includes both structure- and ligand-based evaluations. The de novo approach is an alternative to a blind virtual screening of large compound collections. A heuristic based on a genetic algorithm rapidly finds which fragments or combination of fragments fit a QSAR model or the binding site of a protein. While the approach is ideally suited for scaffold-hopping, this module also allows a scan for possible substituents to a user-specified scaffold. The second tool offers a traditional virtual screening and filtering of an uploaded library of compounds. The third module addresses the combinatorial library design that is based on a user-drawn scaffold and reactants coming, for example, from a chemical supplier. The e-LEA3D server is available at: http://bioinfo.ipmc.cnrs.fr/lea.html. PMID:20444867

  9. PARIS II: Computer Aided Solvent Design for Pollution Prevention

    EPA Science Inventory

    This product is a summary of U.S. EPA researchers' work developing the solvent substitution software tool PARIS II (Program for Assisting the Replacement of Industrial Solvents, version 2.0). PARIS II finds less toxic solvents or solvent mixtures to replace more toxic solvents co...

  10. Computer aided design of a bipolar lead/acid battery

    NASA Astrophysics Data System (ADS)

    Kao, Wen-Hong

    Statistical design of experiments, coupled with the proprietary mathematical lead/acid model of Johnson Controls, Inc., were used to derive the design of a very high power bipolar lead/acid battery for the Jet Propulsion Laboratory. The effects of some battery component factors and discharge rate on the battery performance, predicted by the lead/acid model, were evaluated. The strategy to derive the optimum battery design, the roles of each battery component, limitations of the system, and the directions to improve the battery performance are discussed.

  11. Improved plug valve computer-aided design of plug element

    SciTech Connect

    Wordin, J.J.

    1990-02-01

    The purpose of this document is to present derivations of equations for the design of a plug valve and to present a computer program which performs the design calculations based on the derivations. The valve is based on a plug formed from a tractrix of revolution called a pseudosphere. It is of interest to be able to calculate various parameters for the plug for design purposes. For example, the surface area, volume, and center of gravity are important to determine friction and wear of the valve. A computer program in BASIC has been written to perform the design calculations. The appendix contains a computer program listing and verifications of results using approximation methods. A sample run is included along with necessary computer commands to run the program. 1 fig.

  12. Computer-Aided Apparel Design in University Curricula.

    ERIC Educational Resources Information Center

    Belleau, Bonnie D.; Bourgeois, Elva B.

    1991-01-01

    As computer-assisted design (CAD) become an integral part of the fashion industry, universities must integrate CAD into the apparel curriculum. Louisiana State University's curriculum enables students to collaborate in CAD problem solving with industry personnel. (SK)

  13. Computer-aided space shuttle orbiter wing design study

    NASA Technical Reports Server (NTRS)

    Phillips, W. P.; Decker, J. P.; Rau, T. R.; Glatt, C. R.

    1974-01-01

    An analytical and experimental investigation has been made to provide a space shuttle orbiter wing design that met the guideline requirements of landing performance, stability, and hypersonic trim for a specified center-of-gravity envelope. The analytical study was facilitated by the use of the Optimal Design Integration system (ODIN) and the experimental part of the investigation was conducted in the Langley low-turbulence pressure tunnel and the Langley continuous-flow hypersonic tunnel.

  14. Computer aids for the design of subdivisions for solar access

    SciTech Connect

    Clark, M.M.

    1985-01-01

    Two analytical tools were developed to aid surveyors, architects, and planners in siting solar devices. The tools are in the form of computer programs that produce numerical and graphic data. One program plots the shadows in an area for a given date, time and place. If a composite shadow for an entire day is required, the user can request shadow plots for more than one time. A second program computes the solar envelope for a parcel of land. These are useful for modification of zoning and buildable volume requirements for a parcel. If a dwelling is situated entirely within the envelope, owners of neighboring parcels can be guaranteed that their solar access will be preserved. Output is in the form of elevation differences between the terrain and the envelope and a perspective view of the envelope. Stochastic analysis of the mathematical models is discussed. This includes propagation of random error in the measuring system and comparison of computer generated data with actual ground measurements. Some legal concerns of solar access and the problem of blocking sunlight are also discussed.

  15. TOWARD THE COMPUTER-AIDED DESIGN OF ION SEQUESTERING AGENTS

    SciTech Connect

    Hay, Benjamin

    2008-01-01

    A major impediment to introduction of new extractants to practical use is the large cost and long lead times for synthesis and testing of candidate molecules. Toward the goal of reducing this experimental burden, this talk describes a computational approach to the design of molecular receptors that are structurally organized for optimal coordination with ions. With a molecular-level understanding of how host architecture influences ion-binding affinity, it is possible to identify promising potential extractants before they are prepared and tested. Exploiting powerful concepts embodied in structure-based drug design to bear on host design, we have devised novel algorithms for building potential host structures from molecular fragments and rapid methods for comparing the binding-site organization of the resulting candidates. The result is a computer software program, called HostDesigner, which can generate and evaluate millions of new molecular structures per minute on a desktop personal computer. The utility of this software has been illustrated in the structural design of cation receptors such as crown ethers and anion receptors bearing urea groups.

  16. Computer aided optimal design of compressed air energy storage systems

    NASA Astrophysics Data System (ADS)

    Ahrens, F. W.; Sharma, A.; Ragsdell, K. M.

    1980-07-01

    An automated procedure for the design of Compressed Air Energy Storage (CAES) systems is presented. The procedure relies upon modern nonlinear programming algorithms, decomposition theory, and numerical models of the various system components. Two modern optimization methods are employed; BIAS, a Method of Multipliers code and OPT, a Generalized Reduced Gradient code. The procedure is demonstrated by the design of a CAES facility employing the Media, Illinois Galesville aquifer as the reservoir. The methods employed produced significant reduction in capital and operating cost, and in number of aquifer wells required.

  17. Computer-aided design of optimal infrared detector preamplifiers

    NASA Astrophysics Data System (ADS)

    Frodsham, D. G.; Baker, D. J.

    1980-01-01

    The paper presents a mathematical model for a frequency-compensated detector-preamplifier suitable for cryogenically cooled IR sensors operating under low background conditions. By the use of a digital computer, this model can rapidly select the optimal combination of design values. These parameters include load resistance, compensation resistance, compensation capacitance, chopping frequency, and detector area to meet desired specifications of noise equivalent power, frequency response, dynamic range, and level of output noise. This computer-assisted optimal design approach is demonstrated using a contemporary spaceborne infrared sensor application, i.e., a cryogenically cooled dual-channel radiometer.

  18. Computer-aided design and analysis of mechanisms

    NASA Technical Reports Server (NTRS)

    Knight, F. L.

    1982-01-01

    An introduction to the computer programs developed to assist in the design and analysis of mechanisms is presented. A survey of the various types of programs which are available is given, and the most widely used programs are compared. The way in which the programs are used is discussed, and demonstrated with an example.

  19. Computer-Aided Drug Design of Bioactive Natural Products.

    PubMed

    Prachayasittikul, Veda; Worachartcheewan, Apilak; Shoombuatong, Watshara; Songtawee, Napat; Simeon, Saw; Prachayasittikul, Virapong; Nantasenamat, Chanin

    2015-01-01

    Natural products have been an integral part of sustaining civilizations because of their medicinal properties. Past discoveries of bioactive natural products have relied on serendipity, and these compounds serve as inspiration for the generation of analogs with desired physicochemical properties. Bioactive natural products with therapeutic potential are abundantly available in nature and some of them are beyond exploration by conventional methods. The effectiveness of computational approaches as versatile tools for facilitating drug discovery and development has been recognized for decades, without exception, in the case of natural products. In the post-genomic era, scientists are bombarded with data produced by advanced technologies. Thus, rendering these data into knowledge that is interpretable and meaningful becomes an essential issue. In this regard, computational approaches utilize the existing data to generate knowledge that provides valuable understanding for addressing current problems and guiding the further research and development of new natural-derived drugs. Furthermore, several medicinal plants have been continuously used in many traditional medicine systems since antiquity throughout the world, and their mechanisms have not yet been elucidated. Therefore, the utilization of computational approaches and advanced synthetic techniques would yield great benefit to improving the world's health population and well-being. PMID:25961523

  20. Web-Based Learning in the Computer-Aided Design Curriculum.

    ERIC Educational Resources Information Center

    Sung, Wen-Tsai; Ou, S. C.

    2002-01-01

    Applies principles of constructivism and virtual reality (VR) to computer-aided design (CAD) curriculum, particularly engineering, by integrating network, VR and CAD technologies into a Web-based learning environment that expands traditional two-dimensional computer graphics into a three-dimensional real-time simulation that enhances user…

  1. Improving a Student's Reading Comprehension Skills by Teaching Computer Aided Design.

    ERIC Educational Resources Information Center

    Bentivolio, Kerry

    A serendipitous observation resulted in an examination of the effectiveness of using a computer aided design course to improve high school student's strategic reading skills. Conducted in a 3 month semester period, the study relied on teacher observations, student questionnaires, and personal interviews. More than 75% of the students in the…

  2. Gathering Empirical Evidence Concerning Links between Computer Aided Design (CAD) and Creativity

    ERIC Educational Resources Information Center

    Musta'amal, Aede Hatib; Norman, Eddie; Hodgson, Tony

    2009-01-01

    Discussion is often reported concerning potential links between computer-aided designing and creativity, but there is a lack of systematic enquiry to gather empirical evidence concerning such links. This paper reports an indication of findings from other research studies carried out in contexts beyond general education that have sought evidence…

  3. The state of PC-based CADD (computer-aided design and drafting) systems

    SciTech Connect

    Brandt, G.L.; Bowers, J.M.; Gorman, T.S.; Taylor, L.E.

    1988-07-11

    This report provides an overview of the state of the art of personal computer (PC)-based computer-aided design and drafting (CADD) systems for mechanical engineering applications. It presents the results of an evaluation performed on seven systems during October 1987 to March 1988 and summarizes the strengths and weaknesses of the systems.

  4. Molecular Similarity in Computer-Aided Molecular Design.

    NASA Astrophysics Data System (ADS)

    Hodgkin, Edward E.

    Available from UMI in association with The British Library. Requires signed TDF. The quantitative measurement of how similar one molecule is to another is investigated as a potential aid to molecular design. The work concentrates on the comparison of electronic properties of molecules, in particular electron density distribution, molecular electrostatic potential, molecular electric field and frontier orbital wavefunctions. A novel formula for molecular similarity has been devised and applied to these four properties. An approximate representation of valence electron density is used, based on the notion that charge distribution in a large molecule may be built from transferable contributions from its constituent functional groups. Each of these contributions consists of a series of first-order gaussian functions. The electrostatic potentials and electric fields used in the similarity calculations are computed from atom -centered partial charges. The frontier orbital wavefunction comparisons are performed using the extended Huckel method. The four measures of similarity are related to chemical and biological data and shown to have possible applications in the area of drug design.

  5. Computer-Aided Molecular Design of Bis-phosphine Oxide Lanthanide Extractants.

    PubMed

    McCann, Billy W; Silva, Nuwan De; Windus, Theresa L; Gordon, Mark S; Moyer, Bruce A; Bryantsev, Vyacheslav S; Hay, Benjamin P

    2016-06-20

    Computer-aided molecular design and high-throughput screening of viable host architectures can significantly reduce the efforts in the design of novel ligands for efficient extraction of rare earth elements. This paper presents a computational approach to the deliberate design of bis-phosphine oxide host architectures that are structurally organized for complexation of trivalent lanthanides. Molecule building software, HostDesigner, was interfaced with molecular mechanics software, PCModel, providing a tool for generating and screening millions of potential R2(O)P-link-P(O)R2 ligand geometries. The molecular mechanics ranking of ligand structures is consistent with both the solution-phase free energies of complexation obtained with density functional theory and the performance of known bis-phosphine oxide extractants. For the case where the link is -CH2-, evaluation of the ligand geometry provides the first characterization of a steric origin for the "anomalous aryl strengthening" effect. The design approach has identified a number of novel bis-phosphine oxide ligands that are better organized for lanthanide complexation than previously studied examples. PMID:26883005

  6. [Computer-aided design of polyketides with the required properties].

    PubMed

    Sergeĭko, A P; Stepanchikova, A V; Sobolev, B N; Zotchev, S B; Lagunin, A A; Filimonov, D A; Poroĭkov, V V

    2007-01-01

    We propose an approach to rational design of new polyketides with the required spectrum of biological activity. We developed BioGenPharm software for generation of polyketide combinatorial libraries, prediction of activity spectra for the generated structures and selection of molecules with the required properties on the basis of user defined input parameters and selection criteria. For prediction of polyketide activity spectra we used PASS algorithm (http://www.ibmc.msk.ru/PASS). Validation of PASS prediction ability for polyketides was performed vs. the evaluation set containing 242 natural macrolides from the Dictionary of Natural Products. The mean prediction accuracy was 75,5%. The problem of choice of cutting points for probability of the presence of activity (Pa), which provide optimal combination of such parameters as sensitivity, specificity, concordance was considered. Applicability of the described method has been illustrated by generation of a virtual library of the erythromycin analogues and selection substances for which the probability of hepatotoxic action is low. PMID:18078066

  7. A non-linear programming approach to the computer-aided design of regulators using a linear-quadratic formulation

    NASA Technical Reports Server (NTRS)

    Fleming, P.

    1985-01-01

    A design technique is proposed for linear regulators in which a feedback controller of fixed structure is chosen to minimize an integral quadratic objective function subject to the satisfaction of integral quadratic constraint functions. Application of a non-linear programming algorithm to this mathematically tractable formulation results in an efficient and useful computer-aided design tool. Particular attention is paid to computational efficiency and various recommendations are made. Two design examples illustrate the flexibility of the approach and highlight the special insight afforded to the designer.

  8. Computer-aided design of a proton pump

    NASA Technical Reports Server (NTRS)

    New, Michael H.; Pohorille, Andrew; Chang, Sherwood (Technical Monitor)

    1997-01-01

    The use of transmembrane proton gradients in energy transduction is an almost universal feature of life on earth. These proton gradients are established and maintained by specialized assemblies of proteins which actively pump protons across membranes. One broad class of proton pumps uses captured light energy to drive the proton pumping. Our goal is to elucidate the minimum structural requirements of a light-driven proton-pump. There are two basic components to a simple light-driven proton pump: a source of photo-generated protons and a "gate-keeper" which prevents these protons from reattaching themselves to their source. A wide variety of molecules in the membrane, even as simple as polycyclic aromatic hydrocarbons, are capable of releasing protons when illuminated. Our work is therefore focused on the design of the "gate-keeper." Our initial model involves a pair of proton acceptors, coupled to each other by a transient water bridge, and supported in the membrane by a small bundle of peptide helices. Upon illumination, the proton source transfers its proton to the:- first acceptor of the gate-keeper. While the reverse reaction is highly probable, all that is needed to ensure irreversibility is a nonvanishing probability that the proton will be transferred to the second acceptor across a transient water bridge. Back transfer of the proton to the first acceptor, and thence to the proton source, is impeded by the free energy required to move the proton uphill towards the. proton source and by the disruption of the transient water bridge. As a prototypical water-bridged proton transfer system, we are studying the transfer of a proton across a water bridge from a formic acid to a formate anion. With a pK(sub alpha), of 3.7. formic acid is a good model for the acidic amino acids glutamate and aspartate which are good candidates for gate-keeper proton acceptors. Simulations of proton transfer reactions in a membrane are complicated by the quantum mechanical nature of

  9. Leadless chip carrier packaging and CAD/CAM (Computer-Aided Design/Computer-Aided Manufacturing) supported wire wrap interconnect technology for subnanosecond ECL (Emitter Coupled Logic)

    NASA Astrophysics Data System (ADS)

    Gilbert, B. K.

    1982-12-01

    This document is the third year interim report for a four-year program to refine and develop Computer-Aided Design protocols for implementation of subnanosceond Emitter Coupled Logic in High-Speed Computer Modules using a wire wrap interconnection medium. The software and user manual for implementation guides are not part of the actual report. This report describes the results of work conducted in the third year of a four year program to develop rapid methods for designing and prototyping high-speed digital processor systems using subnanosecond emitter coupled logic (ECL). The third year effort was divided into two separate sets of tasks. In Task 1, described in Sections 3 - 7 of this report, we have nearly completed development of new sets of design rules, interconnection protocols, special components, and logic panels, for a technology based upon specially designed leadless ceramic chip carriers developed at Mayo Foundation. Task 2, described in Sections 8 and IX of this report, continued the development of a comprehensive computer-aided design/computer-aided manufacturing (CAD/CAM) software package which is specifically tailored to support the peculiar design requirements of processors operating in a high clock rate, transmission line environment, either with subnanosecond ECL components or with any other families of subnanosecond devices.

  10. Performance evaluation of computer aided diagnostic tool (CAD) for detection of ultrasonic based liver disease.

    PubMed

    Sriraam, N; Roopa, J; Saranya, M; Dhanalakshmi, M

    2009-08-01

    Recent advances in digital imaging technology have greatly enhanced the interpretation of critical/pathology conditions from the 2-dimensional medical images. This has become realistic due to the existence of the computer aided diagnostic tool. A computer aided diagnostic (CAD) tool generally possesses components like preprocessing, identification/selection of region of interest, extraction of typical features and finally an efficient classification system. This paper enumerates on development of CAD tool for classification of chronic liver disease through the 2-D image acquired from ultrasonic device. Characterization of tissue through qualitative treatment leads to the detection of abnormality which is not viable through qualitative visual inspection by the radiologist. Common liver diseases are the indicators of changes in tissue elasticity. One can show the detection of normal, fatty or malignant condition based on the application of CAD tool thereby, further investigation required by radiologist can be avoided. The proposed work involves an optimal block analysis (64 x 64) of the liver image of actual size 256 x 256 by incorporating Gabor wavelet transform which does the texture classification through automated mode. Statistical features such as gray level mean as well as variance values are estimated after this preprocessing mode. A non-linear back propagation neural network (BPNN) is applied for classifying the normal (vs) fatty and normal (vs) malignant liver which yields a classification accuracy of 96.8%. Further multi classification is also performed and a classification accuracy of 94% is obtained. It can be concluded that the proposed CAD can be used as an expert system to aid the automated diagnosis of liver diseases. PMID:19697693

  11. Investigation into the development of computer aided design software for space based sensors

    NASA Technical Reports Server (NTRS)

    Pender, C. W.; Clark, W. L.

    1987-01-01

    The described effort is phase one of the development of a Computer Aided Design (CAD) software to be used to perform radiometric sensor design. The software package will be referred to as SCAD and is directed toward the preliminary phase of the design of space based sensor system. The approach being followed is to develop a modern, graphic intensive, user friendly software package using existing software as building blocks. The emphasis will be directed toward the development of a shell containing menus, smart defaults, and interfaces, which can accommodate a wide variety of existing application software packages. The shell will offer expected utilities such as graphics, tailored menus, and a variety of drivers for I/O devices. Following the development of the shell, the development of SCAD is planned as chiefly selection and integration of appropriate building blocks. The phase one development activities have included: the selection of hardware which will be used with SCAD; the determination of the scope of SCAD; the preliminary evaluation of a number of software packages for applicability to SCAD; determination of a method for achieving required capabilities where voids exist; and then establishing a strategy for binding the software modules into an easy to use tool kit.

  12. Comparative study of auxetic geometries by means of computer-aided design and engineering

    NASA Astrophysics Data System (ADS)

    Álvarez Elipe, Juan Carlos; Díaz Lantada, Andrés

    2012-10-01

    Auxetic materials (or metamaterials) are those with a negative Poisson ratio (NPR) and display the unexpected property of lateral expansion when stretched, as well as an equal and opposing densification when compressed. Such geometries are being progressively employed in the development of novel products, especially in the fields of intelligent expandable actuators, shape morphing structures and minimally invasive implantable devices. Although several auxetic and potentially auxetic geometries have been summarized in previous reviews and research, precise information regarding relevant properties for design tasks is not always provided. In this study we present a comparative study of two-dimensional and three-dimensional auxetic geometries carried out by means of computer-aided design and engineering tools (from now on CAD-CAE). The first part of the study is focused on the development of a CAD library of auxetics. Once the library is developed we simulate the behavior of the different auxetic geometries and elaborate a systematic comparison, considering relevant properties of these geometries, such as Poisson ratio(s), maximum volume or area reductions attainable and equivalent Young’s modulus, hoping it may provide useful information for future designs of devices based on these interesting structures.

  13. Visualization and modeling of factors influencing visibility in computer-aided crewstation design

    NASA Technical Reports Server (NTRS)

    Arditi, Aries; Azueta, Steven; Larimer, James; Prevost, Michael; Lubin, Jeffrey; Bergen, James

    1992-01-01

    We have developed two modules for use in computer-aided design (CAD) of crewstation environments that enhance the designer's appreciation of factors influencing the pilot's vision and visual processing capacity. The Binocular Optics Module (BOM) is an interactive tool for visualizing geometric aspects of (1) how retinal imagery of the environment changes on the pilot's retinas under conditions of eye and object motion, and (2) how visual capabilities that can be modeled as regions or contours on the retinas, affect spatial perception of the environment. The Visual Performance Module (VPM) contains a signal processing model of human visual discrimination that quantitatively predicts visual discrimination performance. The outputs of the VPM are retinal contours that represent performance probabilities. These contours may be used as inputs to the BOM for visualizing those volumes of space within the crewstation that bound different levels of the pilot's of visual discrimination capability. Used together, the BOM and VPM provide the designer with the opportunity to interactively explore relationships between environmental retinal imagery and visual function, and the ability to factor the pilot's visual capabilities into the earliest phases of crewstation CAD.

  14. Computer-aided design of millimeter-wave E-plane filters

    NASA Astrophysics Data System (ADS)

    Shih, Y.-C.; Itoh, T.; Bui, L. Q.

    1983-02-01

    A computer-aided design (CAD) algorithm has been developed for a class of E-plane bandpass filters. The analysis portion of the algorithm is based on the residue-calculus technique and a generalized scattering parameter method. It is mathematically exact and numerically very efficient. Filters designed with this method have been fabricated and tested in Ka-band. Good agreement with design has been obtained.

  15. Task analysis for computer-aided design (CAD) at a keystroke level.

    PubMed

    Chi, C F; Chung, K L

    1996-08-01

    The purpose of this research was to develop a new model to describe and predict a computerized task. AutoCAD was utilized as the experimental tool to collect operating procedure and time data at a keystroke level for a computer aided design (CAD) task. Six undergraduate students participated in the experiment. They were required to complete one simple and one complex engineering drawing. A model which characterized the task performance by software commands and predicted task execution time using keystroke-level model operators was proposed and applied to the analysis of the dialogue data. This task parameter model adopted software commands, e.g. LINE, OFFSET in AutoCAD, to describe the function of a task unit and used up to five parameters to indicate the number of keystrokes, chosen function for a command and ways of starting and ending a command. Each task unit in the task parameter model can be replaced by a number of primitive operators as in the keystroke level model to predict the task execution time. The observed task execution times of all task units were found to be highly correlated with the task execution times predicted by the keystroke level model. Therefore, the task parameter model was proved to be a usable analytical tool for evaluating the human-computer interface (HCI). PMID:15677066

  16. Use of the surface-based registration function of computer-aided design/computer-aided manufacturing software in medical simulation software for three-dimensional simulation of orthognathic surgery

    PubMed Central

    Lee, Jae-Won; Kim, Moon-Key

    2013-01-01

    Three-dimensional (3D) computed tomography image models are helpful in reproducing the maxillofacial area; however, they do not necessarily provide an accurate representation of dental occlusion and the state of the teeth. Recent efforts have focused on improvement of dental imaging by replacement of computed tomography with other detailed digital images. Unfortunately, despite the advantages of medical simulation software in dentofacial analysis, diagnosis, and surgical simulation, it lacks adequate registration tools. Following up on our previous report on orthognathic simulation surgery using computer-aided design/computer-aided manufacturing (CAD/CAM) software, we recently used the registration functions of a CAD/CAM platform in conjunction with surgical simulation software. Therefore, we would like to introduce a new technique, which involves use of the registration functions of CAD/CAM software followed by transfer of the images into medical simulation software. This technique may be applicable when using various registration function tools from different software platforms. PMID:24471043

  17. Use of the surface-based registration function of computer-aided design/computer-aided manufacturing software in medical simulation software for three-dimensional simulation of orthognathic surgery.

    PubMed

    Kang, Sang-Hoon; Lee, Jae-Won; Kim, Moon-Key

    2013-08-01

    Three-dimensional (3D) computed tomography image models are helpful in reproducing the maxillofacial area; however, they do not necessarily provide an accurate representation of dental occlusion and the state of the teeth. Recent efforts have focused on improvement of dental imaging by replacement of computed tomography with other detailed digital images. Unfortunately, despite the advantages of medical simulation software in dentofacial analysis, diagnosis, and surgical simulation, it lacks adequate registration tools. Following up on our previous report on orthognathic simulation surgery using computer-aided design/computer-aided manufacturing (CAD/CAM) software, we recently used the registration functions of a CAD/CAM platform in conjunction with surgical simulation software. Therefore, we would like to introduce a new technique, which involves use of the registration functions of CAD/CAM software followed by transfer of the images into medical simulation software. This technique may be applicable when using various registration function tools from different software platforms. PMID:24471043

  18. Integration of computer-aided design and manufacturing through artificial-intelligence-based process planning

    SciTech Connect

    Arunthavanathan, V.

    1988-01-01

    The research effort reported in this thesis is directed towards the integration of design, process planning, and manufacturing. The principal notion used in system integration through information integration. The main outcome of this research effort is an artificial-intelligence-based computer-aided generative process planning system, which would use a feature-based symbolic geometry as its input. The feature-based symbolic data structure is used as the common data between design, process planning, and manufacturing. As the commercial computer-aided design systems would not generate a feature-based data base, special interfaces are designed and used. As part of the solution strategy, a module to analyze the symbolic geometry from a global perspective is developed. This module imitates a human process planner and derives some overall assertions. The enhanced geometry data is then used by a rule-based expert system to develop the process plan.

  19. Progress of computer-aided drug design (CADD) of proteasome inhibitors.

    PubMed

    Lei, Meng; Liu, Yunde; Zhu, Yongqiang; Liu, Zhenming

    2011-12-01

    The target proteasome has been the focus of drug discovery since the first drug bortezomib was launched in 2003. Many structurally diverse proteasome inhibitors were discovered and even some of them entered the clinical trials. Due to rapid technological progress in chemistry, bioinformatics, structural biology and computer technology, computer-aided drug design (CADD) plays a more and more important role in today's drug discovery. Many CADD technologies were employed in designing various inhibitors of proteasome in the past years. This review gives a global description of the development of computer-aided proteasome inhibitor design by using different commercial or academic software. The binding modes of some structurally novel inhibitors with proteasome were visualized with these new technologies. PMID:21824106

  20. The vehicle design evaluation program - A computer-aided design procedure for transport aircraft

    NASA Technical Reports Server (NTRS)

    Oman, B. H.; Kruse, G. S.; Schrader, O. E.

    1977-01-01

    The vehicle design evaluation program is described. This program is a computer-aided design procedure that provides a vehicle synthesis capability for vehicle sizing, external load analysis, structural analysis, and cost evaluation. The vehicle sizing subprogram provides geometry, weight, and balance data for aircraft using JP, hydrogen, or methane fuels. The structural synthesis subprogram uses a multistation analysis for aerodynamic surfaces and fuselages to develop theoretical weights and geometric dimensions. The parts definition subprogram uses the geometric data from the structural analysis and develops the predicted fabrication dimensions, parts material raw stock buy requirements, and predicted actual weights. The cost analysis subprogram uses detail part data in conjunction with standard hours, realization factors, labor rates, and material data to develop the manufacturing costs. The program is used to evaluate overall design effects on subsonic commercial type aircraft due to parameter variations.

  1. Applied, theoretical modeling of space-based assembly, using expert system architecture for computer-aided engineering tool development

    NASA Astrophysics Data System (ADS)

    Jolly, Steven Douglas

    1992-01-01

    The challenges associated with constructing interplanetary spacecraft and space platforms in low earth orbit are such that it is imperative that comprehensive, preliminary process planning analyses be completed before committing funds for Phase B design (detail design, development). Phase A and 'pre-Phase A' design activities will commonly address engineering questions such as mission-design structural integrity, attitude control, thermal control, etc. But the questions of constructability, maintainability and reliability during the assembly phase usually go unaddressed until the more mature stages of design (or very often production) are reached. This is an unacceptable strategy for future space missions whether they be government or commercial ventures. After interviews with expert Aerospace and Construction industry planners a new methodology was formulated and a Blackboard Metaphor Knowledge-based Expert System synthesis model has been successfully developed which can decompose interplanetary vehicles into deliverable orbital subassemblies. Constraint propagation, including launch vehicle payload shroud envelope, is accomplished with heuristic and numerical algorithms including a unique adaptation of a reasoning technique used by Stanford researchers in terrestrial automated process planning. The model is a hybrid combination of rule and frame-based representations, designed to integrate into a Computer-Aided Engineering (CAE) environment. Emphasis is placed on the actual joining, rendezvous, and refueling of the orbiting, dynamic spacecraft. Significant results of this new methodology upon a large Mars interplanetary spacecraft (736,000 kg) designed by Boeing, show high correlation to manual decomposition and planning analysis studies, but at a fraction of the time, and with little user interaction. Such Computer-Aided Engineering (CAE) tools would greatly leverage the designers ability to assess constructability.

  2. The Design and Evaluation of "CAPTools"--A Computer Aided Parallelization Toolkit

    NASA Technical Reports Server (NTRS)

    Yan, Jerry; Frumkin, Michael; Hribar, Michelle; Jin, Haoqiang; Waheed, Abdul; Johnson, Steve; Cross, Jark; Evans, Emyr; Ierotheou, Constantinos; Leggett, Pete; Saini, Subhash (Technical Monitor)

    1998-01-01

    Writing applications for high performance computers is a challenging task. Although writing code by hand still offers the best performance, it is extremely costly and often not very portable. The Computer Aided Parallelization Tools (CAPTools) are a toolkit designed to help automate the mapping of sequential FORTRAN scientific applications onto multiprocessors. CAPTools consists of the following major components: an inter-procedural dependence analysis module that incorporates user knowledge; a 'self-propagating' data partitioning module driven via user guidance; an execution control mask generation and optimization module for the user to fine tune parallel processing of individual partitions; a program transformation/restructuring facility for source code clean up and optimization; a set of browsers through which the user interacts with CAPTools at each stage of the parallelization process; and a code generator supporting multiple programming paradigms on various multiprocessors. Besides describing the rationale behind the architecture of CAPTools, the parallelization process is illustrated via case studies involving structured and unstructured meshes. The programming process and the performance of the generated parallel programs are compared against other programming alternatives based on the NAS Parallel Benchmarks, ARC3D and other scientific applications. Based on these results, a discussion on the feasibility of constructing architectural independent parallel applications is presented.

  3. Computer-aided analysis and design of the shape rolling process for producing turbine engine airfoils

    NASA Technical Reports Server (NTRS)

    Lahoti, G. D.; Akgerman, N.; Altan, T.

    1978-01-01

    Mild steel (AISI 1018) was selected as model cold rolling material and Ti-6A1-4V and Inconel 718 were selected as typical hot rolling and cold rolling alloys, respectively. The flow stress and workability of these alloys were characterized and friction factor at the roll/workpiece interface was determined at their respective working conditions by conducting ring tests. Computer-aided mathematical models for predicting metal flow and stresses, and for simulating the shape rolling process were developed. These models utilized the upper bound and the slab methods of analysis, and were capable of predicting the lateral spread, roll separating force, roll torque, and local stresses, strains and strain rates. This computer-aided design system was also capable of simulating the actual rolling process, and thereby designing the roll pass schedule in rolling of an airfoil or a similar shape.

  4. Computer-Aided Designed, 3-Dimensionally Printed Porous Tissue Bioscaffolds For Craniofacial Soft Tissue Reconstruction

    PubMed Central

    Zopf, David A.; Mitsak, Anna G.; Flanagan, Colleen L.; Wheeler, Matthew; Green, Glenn E.; Hollister, Scott J.

    2016-01-01

    Objectives To determine the potential of integrated image-based Computer Aided Design (CAD) and 3D printing approach to engineer scaffolds for head and neck cartilaginous reconstruction for auricular and nasal reconstruction. Study Design Proof of concept revealing novel methods for bioscaffold production with in vitro and in vivo animal data. Setting Multidisciplinary effort encompassing two academic institutions. Subjects and Methods DICOM CT images are segmented and utilized in image-based computer aided design to create porous, anatomic structures. Bioresorbable, polycaprolactone scaffolds with spherical and random porous architecture are produced using a laser-based 3D printing process. Subcutaneous in vivo implantation of auricular and nasal scaffolds was performed in a porcine model. Auricular scaffolds were seeded with chondrogenic growth factors in a hyaluronic acid/collagen hydrogel and cultured in vitro over 2 months duration. Results Auricular and nasal constructs with several microporous architectures were rapidly manufactured with high fidelity to human patient anatomy. Subcutaneous in vivo implantation of auricular and nasal scaffolds resulted in excellent appearance and complete soft tissue ingrowth. Histologic analysis of in vitro scaffolds demonstrated native appearing cartilaginous growth respecting the boundaries of the scaffold. Conclusions Integrated image-based computer-aided design (CAD) and 3D printing processes generated patient-specific nasal and auricular scaffolds that supported cartilage regeneration. PMID:25281749

  5. Integrating aerodynamic surface modeling for computational fluid dynamics with computer aided structural analysis, design, and manufacturing

    NASA Technical Reports Server (NTRS)

    Thorp, Scott A.

    1992-01-01

    This presentation will discuss the development of a NASA Geometry Exchange Specification for transferring aerodynamic surface geometry between LeRC systems and grid generation software used for computational fluid dynamics research. The proposed specification is based on a subset of the Initial Graphics Exchange Specification (IGES). The presentation will include discussion of how the NASA-IGES standard will accommodate improved computer aided design inspection methods and reverse engineering techniques currently being developed. The presentation is in viewgraph format.

  6. Computer-aided design and drafting visualization of anatomical structure of the human eye and orbit

    NASA Astrophysics Data System (ADS)

    Parshall, Robert F.; Sadler, Lewis L.

    1991-04-01

    A generalized " anatomically standard" eyeball was geometrically modeled on a Computer-Aided Design and Drafting (CADD) workstation based on published conceptual norms of dimension radii of curvature alignments etc. An orbital environment for this model was concurrently prepared by serial section reconstruction of a cadaver specimen. Issues addressed include orienting unregistered sections the utility of interactive CADDsupported visual logic in interpretive decision making and the value of geometric models.

  7. Implementation and display of Computer Aided Design (CAD) models in Monte Carlo radiation transport and shielding applications

    SciTech Connect

    Burns, T.J.

    1994-03-01

    An Xwindow application capable of importing geometric information directly from two Computer Aided Design (CAD) based formats for use in radiation transport and shielding analyses is being developed at ORNL. The application permits the user to graphically view the geometric models imported from the two formats for verification and debugging. Previous models, specifically formatted for the radiation transport and shielding codes can also be imported. Required extensions to the existing combinatorial geometry analysis routines are discussed. Examples illustrating the various options and features which will be implemented in the application are presented. The use of the application as a visualization tool for the output of the radiation transport codes is also discussed.

  8. Evaluation of computer-aided design and drafting for the electric power industry. Final report

    SciTech Connect

    Anuskiewicz, T.; Barduhn, G.; Lowther, B.; Osman, I.

    1984-01-01

    This report reviews current and future computer-aided design and drafting (CADD) technology relative to utility needs and to identify useful development projects that may be undertaken by EPRI. The principal conclusions are that computer aids offer substantial cost and time savings and that computer systems are being developed to take advantage of the savings. Data bases are not available for direct communication between computers used by the power industry and will limit benefits to the industry. Recommendations are made for EPRI to take the initiative to develop the data bases for direct communication between power industry computers and to research, develop, and demonstrate new applications within the industry. Key components of a CADD system are described. The state of the art of two- and three-dimensional CADD systems to perform graphics and project management control functions are assessed. Comparison is made of three-dimensional electronic models and plastic models.

  9. Ratsnake: A Versatile Image Annotation Tool with Application to Computer-Aided Diagnosis

    PubMed Central

    Iakovidis, D. K.; Goudas, T.; Smailis, C.; Maglogiannis, I.

    2014-01-01

    Image segmentation and annotation are key components of image-based medical computer-aided diagnosis (CAD) systems. In this paper we present Ratsnake, a publicly available generic image annotation tool providing annotation efficiency, semantic awareness, versatility, and extensibility, features that can be exploited to transform it into an effective CAD system. In order to demonstrate this unique capability, we present its novel application for the evaluation and quantification of salient objects and structures of interest in kidney biopsy images. Accurate annotation identifying and quantifying such structures in microscopy images can provide an estimation of pathogenesis in obstructive nephropathy, which is a rather common disease with severe implication in children and infants. However a tool for detecting and quantifying the disease is not yet available. A machine learning-based approach, which utilizes prior domain knowledge and textural image features, is considered for the generation of an image force field customizing the presented tool for automatic evaluation of kidney biopsy images. The experimental evaluation of the proposed application of Ratsnake demonstrates its efficiency and effectiveness and promises its wide applicability across a variety of medical imaging domains. PMID:24616617

  10. Initial development of a computer-aided diagnosis tool for solitary pulmonary nodules

    NASA Astrophysics Data System (ADS)

    Catarious, David M., Jr.; Baydush, Alan H.; Floyd, Carey E., Jr.

    2001-07-01

    This paper describes the development of a computer-aided diagnosis (CAD) tool for solitary pulmonary nodules. This CAD tool is built upon physically meaningful features that were selected because of their relevance to shape and texture. These features included a modified version of the Hotelling statistic (HS), a channelized HS, three measures of fractal properties, two measures of spicularity, and three manually measured shape features. These features were measured from a difficult database consisting of 237 regions of interest (ROIs) extracted from digitized chest radiographs. The center of each 256x256 pixel ROI contained a suspicious lesion which was sent to follow-up by a radiologist and whose nature was later clinically determined. Linear discriminant analysis (LDA) was used to search the feature space via sequential forward search using percentage correct as the performance metric. An optimized feature subset, selected for the highest accuracy, was then fed into a three layer artificial neural network (ANN). The ANN's performance was assessed by receiver operating characteristic (ROC) analysis. A leave-one-out testing/training methodology was employed for the ROC analysis. The performance of this system is competitive with that of three radiologists on the same database.

  11. Computer-aided optimization of grid design for high-power lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Yamada, Keizo; Maeda, Ken-ichi; Sasaki, Kazuya; Hirasawa, Tokiyoshi

    Several high-power lead-acid batteries have been developed for automotive applications. A computer-aided optimization (CAO) technique has been used to obtain a low-resistance grid design. Unlike conventional computer simulation, the CAO technique does not require an unduly large number of designs to yield a good result. After introducing a pair of differential equations that are expected to be valid for the optimized design, the grid thickness is optimized by solving the boundary value problem of coupled differential equations. When applied for the grids of JIS B-size batteries, this technique reduces the potential drop of electrical resistance in a electrode by 11-14%.

  12. Metalloporphyrin catalysts for oxygen reduction developed using computer-aided molecular design

    SciTech Connect

    Ryba, G.N.; Hobbs, J.D.; Shelnutt, J.A.

    1996-04-01

    The objective of this project is the development of a new class of metalloporphyrin materials used as catalsyts for use in fuel cell applications. The metalloporphyrins are excellent candidates for use as catalysts at both the anode and cathode. The catalysts reduce oxygen in 1 M potassium hydroxide, as well as in 2 M sulfuric acid. Covalent attachment to carbon supports is being investigated. The computer-aided molecular design is an iterative process, in which experimental results feed back into the design of future catalysts.

  13. Prosthetic rehabilitation with an implant-supported fixed prosthesis using computer-aided design and computer-aided manufacturing dental technology for a patient with a mandibulectomy: A clinical report.

    PubMed

    Yoon, Hyung-In; Han, Jung-Suk

    2016-02-01

    The fabrication of dental prostheses with computer-aided design and computer-aided manufacturing shows acceptable marginal fits and favorable treatment outcomes. This clinical report describes the management of a patient who had undergone a mandibulectomy and received an implant-supported fixed prosthesis by using additive manufacturing for the framework and subtractive manufacturing for the monolithic zirconia restorations. PMID:26518985

  14. CADIS: a kernel approach toward the development of intelligent data-management support for computer-aided design systems

    SciTech Connect

    Landis, D.M.

    1988-01-01

    Design and development of CADIS (Computer Aided Design Information System) is presented. CADIS addresses the data-management needs of Computer Aided Design (CAD) systems by providing a system that overcomes the inherent problems found when using conventional data base management systems (DBMS). Limitations found with other research and development efforts marked for correction include: lack of flexibility in the supported CAD system, separation of the design interaction from data-base interaction, separation of knowledge-base issues from data-management issues, lack of a distinction between a DBMS' implementation of system policy, and a DBMS mechanism to support system policy. A four-level data-base architecture is defined for CADIS. An augmented entity-relationship model (AERM) is also defined that supports the CADIS architecture. This model includes structures developed to specifically overcome limitations found in the use of the more-traditional data model. A definition and manipulation language for the model are defined. Translation rules derived enable the AERM to be translated into an underlying data-base scheme. A proof-of-concept model is presented via the definition and implementation of a system tool, the SARA/IDEAS System Browser.

  15. RETRACTED: Auricular prosthesis fabrication using computer-aided design and rapid prototyping technologies.

    PubMed

    Shah, Mayank

    2016-06-01

    At the request of the editorMayank Shah 'Auricular prosthesis fabrication using computer-aided design and rapid prototyping technologies' Prosthetics and Orthotics International, published online before print on October 8, 2013 as doi:10.1177/0309364613504779has been retracted. This is because it contains unattributed overlap withK. Subburaj, C. Nair, S. Rajesh, S. M. Meshram, B. Ravi 'Rapid development of auricular prosthesis using CAD and rapid prototyping technologies' International Journal of Oral & Maxillofacial Surgery 2007; 36: 938-943 doi:10.1016/j.ijom.2007.07.013. PMID:24104058

  16. A convenient method for the computer-aided molecular design of carborane containing compounds.

    PubMed

    Johnsamuel, Jayaseharan; Byun, Youngjoo; Jones, Thomas P; Endo, Yasuyuki; Tjarks, Werner

    2003-10-01

    Computer-aided molecular design (CAMD) of carborane containing compounds is of growing interest for scientists involved in boron neutron capture therapy (BNCT) and other pharmaceutical applications. However, the complex organo-metallic structures of carboranes pose difficulties in modeling and docking of these structures. This is the first report of a new strategy for modeling and docking of carborane containing molecules with the readily available software packages HyperChem, SYBYL and FlexX. It is intended as a guide for boron chemists interested in using CAMD of carborane containing agents for medical applications such as BNCT. PMID:12951095

  17. The multimod application framework: a rapid application development tool for computer aided medicine.

    PubMed

    Viceconti, Marco; Zannoni, Cinzia; Testi, Debora; Petrone, Marco; Perticoni, Stefano; Quadrani, Paolo; Taddei, Fulvia; Imboden, Silvano; Clapworthy, Gordon

    2007-02-01

    This paper describes a new application framework (OpenMAF) for rapid development of multimodal applications in computer-aided medicine. MAF applications are multimodal in data, in representation, and in interaction. The framework supports almost any type of biomedical data, including DICOM datasets, motion-capture recordings, or data from computer simulations (e.g. finite element modeling). The interactive visualization approach (multimodal display) helps the user interpret complex datasets, providing multiple representations of the same data. In addition, the framework allows multimodal interaction by supporting the simultaneous use of different input-output devices like 3D trackers, stereoscopic displays, haptics hardware and speech recognition/synthesis systems. The Framework has been designed to run smoothly even on limited power computers, but it can take advantage of all hardware capabilities. The Framework is based on a collection of portable libraries and it can be compiled on any platform that supports OpenGL, including Windows, MacOS X and any flavor of Unix/linux. PMID:17059851

  18. Computer-Aided Design/Manufacturing (CAD/M) for high-speed interconnect

    NASA Astrophysics Data System (ADS)

    Santoski, N. F.

    1981-10-01

    The objective of the Computer-Aided Design/Manufacturing (CAD/M) for High-Speed Interconnect Program study was to assess techniques for design, analysis and fabrication of interconnect structures between high-speed logic ICs that are clocked in the 200 MHz to 5 GHz range. Interconnect structure models were investigated and integrated with existing device models. Design rules for interconnects were developed in terms of parameters that can be installed in software that is used for the design, analysis and fabrication of circuits. To implement these design rules in future software development, algorithms and software development techniques were defined. Major emphasis was on Printed Wiring Board and hybrid level circuits as opposed to monolithic chips. Various packaging schemes were considered, including controlled impedance lines in the 50 to 200 ohms range where needed. The design rules developed are generic in nature, in that various architecture classes and device technologies were considered.

  19. A Computer-Aided Approach for Designing Edge-Slot Waveguide Arrays

    NASA Technical Reports Server (NTRS)

    Gosselin, Renee Brian

    2003-01-01

    Traditional techniques for designing resonant edge-slot waveguide arrays have required an iterative trial-and-error process of measuring slot data from several prototypes. Since very little meaningful data has been published, this technology remains relatively immature and prohibitive for many smaller programs that could benefit from some advantages this antenna has to offer. A new Computer-Aided Design technique for designing resonant edge-slot waveguide arrays was used to successfuliy design such an X-band radiometer antenna for the NASA Light Rainfall Radiometer (LRR) instrument. Having the ability to rapidly create such an extremely accurate and efficient antenna design without the need to manufacture prototypes has also enabled inexpensive research that promises to improve the system-level performance of microwave radiometers for upcoming space-flight missions. This paper will present details of the LRR antenna design and describe some other current edge-slot array accomplishments at Goddard Space Flight Center.

  20. 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.

  1. Computer-Aided Drug Design (CADD): Methodological Aspects and Practical Applications in Cancer Research

    NASA Astrophysics Data System (ADS)

    Gianti, Eleonora

    Computer-Aided Drug Design (CADD) has deservedly gained increasing popularity in modern drug discovery (Schneider, G.; Fechner, U. 2005), whether applied to academic basic research or the pharmaceutical industry pipeline. In this work, after reviewing theoretical advancements in CADD, we integrated novel and stateof- the-art methods to assist in the design of small-molecule inhibitors of current cancer drug targets, specifically: Androgen Receptor (AR), a nuclear hormone receptor required for carcinogenesis of Prostate Cancer (PCa); Signal Transducer and Activator of Transcription 5 (STAT5), implicated in PCa progression; and Epstein-Barr Nuclear Antigen-1 (EBNA1), essential to the Epstein Barr Virus (EBV) during latent infections. Androgen Receptor. With the aim of generating binding mode hypotheses for a class (Handratta, V.D. et al. 2005) of dual AR/CYP17 inhibitors (CYP17 is a key enzyme for androgens biosynthesis and therefore implicated in PCa development), we successfully implemented a receptor-based computational strategy based on flexible receptor docking (Gianti, E.; Zauhar, R.J. 2012). Then, with the ultimate goal of identifying novel AR binders, we performed Virtual Screening (VS) by Fragment-Based Shape Signatures, an improved version of the original method developed in our Laboratory (Zauhar, R.J. et al. 2003), and we used the results to fully assess the high-level performance of this innovative tool in computational chemistry. STAT5. The SRC Homology 2 (SH2) domain of STAT5 is responsible for phospho-peptide recognition and activation. As a keystone of Structure-Based Drug Design (SBDD), we characterized key residues responsible for binding. We also generated a model of STAT5 receptor bound to a phospho-peptide ligand, which was validated by docking publicly known STAT5 inhibitors. Then, we performed Shape Signatures- and docking-based VS of the ZINC database (zinc.docking.org), followed by Molecular Mechanics Generalized Born Surface Area (MMGBSA

  2. Computer-aided analysis and design of the shape rolling process for producing turbine engine airfoils

    NASA Technical Reports Server (NTRS)

    Lahoti, G. D.; Akgerman, N.; Altan, T.

    1978-01-01

    Mild steel (AISI 1018) was selected as model cold-rolling material and Ti-6Al-4V and INCONEL 718 were selected as typical hot-rolling and cold-rolling alloys, respectively. The flow stress and workability of these alloys were characterized and friction factor at the roll/workpiece interface was determined at their respective working conditions by conducting ring tests. Computer-aided mathematical models for predicting metal flow and stresses, and for simulating the shape-rolling process were developed. These models utilize the upper-bound and the slab methods of analysis, and are capable of predicting the lateral spread, roll-separating force, roll torque and local stresses, strains and strain rates. This computer-aided design (CAD) system is also capable of simulating the actual rolling process and thereby designing roll-pass schedule in rolling of an airfoil or similar shape. The predictions from the CAD system were verified with respect to cold rolling of mild steel plates. The system is being applied to cold and hot isothermal rolling of an airfoil shape, and will be verified with respect to laboratory experiments under controlled conditions.

  3. Modern numerical techniques and software for photo- and thermoemission electron optical systems computer-aided design

    NASA Astrophysics Data System (ADS)

    Monastyrski, Mikhail A.; Andreev, Sergei V.; Gaidukova, Inna S.; Tarasov, Victor A.; Filachev, Anatoly M.

    1997-09-01

    The paper is devoted to software development for simulation, optimization, and computer-aided design of photo/thermo- emission electron optical systems and units. The first part of the paper presents the applied program package (APP) 'ELIMDYNAMICS\\ intended for computer-aided design of dynamic photo-emission image tubes with electro/magnetostatic focusing and deflection (streak tubes). The developed software allows highly precise computation of basic image quality characteristics both in static and streak modes. One of the main advantages of the new program version presented is that 'through' electron beam computation from the photocathode to image receiver is available with regard to dynamic aberrations caused by scattering fields located nearby the edges of deflecting plates. In the second part, the possibility is shown to generalize some numerical techniques being effectively applied in photo-emission imaging electron optics (namely, the (tau) -variation - and the first kind integral equations techniques) to simulation of the thermo-emission electron beam technology units. Functions of the new APP 'CHARGE' are presented, and some numerical aspects of the self-coordinated problem are discussed.

  4. NEXUS/NASCAD- NASA ENGINEERING EXTENDIBLE UNIFIED SOFTWARE SYSTEM WITH NASA COMPUTER AIDED DESIGN

    NASA Technical Reports Server (NTRS)

    Purves, L. R.

    1994-01-01

    NEXUS, the NASA Engineering Extendible Unified Software system, is a research set of computer programs designed to support the full sequence of activities encountered in NASA engineering projects. This sequence spans preliminary design, design analysis, detailed design, manufacturing, assembly, and testing. NEXUS primarily addresses the process of prototype engineering, the task of getting a single or small number of copies of a product to work. Prototype engineering is a critical element of large scale industrial production. The time and cost needed to introduce a new product are heavily dependent on two factors: 1) how efficiently required product prototypes can be developed, and 2) how efficiently required production facilities, also a prototype engineering development, can be completed. NEXUS extendibility and unification are achieved by organizing the system as an arbitrarily large set of computer programs accessed in a common manner through a standard user interface. The NEXUS interface is a multipurpose interactive graphics interface called NASCAD (NASA Computer Aided Design). NASCAD can be used to build and display two and three-dimensional geometries, to annotate models with dimension lines, text strings, etc., and to store and retrieve design related information such as names, masses, and power requirements of components used in the design. From the user's standpoint, NASCAD allows the construction, viewing, modification, and other processing of data structures that represent the design. Four basic types of data structures are supported by NASCAD: 1) three-dimensional geometric models of the object being designed, 2) alphanumeric arrays to hold data ranging from numeric scalars to multidimensional arrays of numbers or characters, 3) tabular data sets that provide a relational data base capability, and 4) procedure definitions to combine groups of system commands or other user procedures to create more powerful functions. NASCAD has extensive abilities to

  5. An investigation of constraint-based component-modeling for knowledge representation in computer-aided conceptual design

    NASA Technical Reports Server (NTRS)

    Kolb, Mark A.

    1990-01-01

    Originally, computer programs for engineering design focused on detailed geometric design. Later, computer programs for algorithmically performing the preliminary design of specific well-defined classes of objects became commonplace. However, due to the need for extreme flexibility, it appears unlikely that conventional programming techniques will prove fruitful in developing computer aids for engineering conceptual design. The use of symbolic processing techniques, such as object-oriented programming and constraint propagation, facilitate such flexibility. Object-oriented programming allows programs to be organized around the objects and behavior to be simulated, rather than around fixed sequences of function- and subroutine-calls. Constraint propagation allows declarative statements to be understood as designating multi-directional mathematical relationships among all the variables of an equation, rather than as unidirectional assignments to the variable on the left-hand side of the equation, as in conventional computer programs. The research has concentrated on applying these two techniques to the development of a general-purpose computer aid for engineering conceptual design. Object-oriented programming techniques are utilized to implement a user-extensible database of design components. The mathematical relationships which model both geometry and physics of these components are managed via constraint propagation. In addition, to this component-based hierarchy, special-purpose data structures are provided for describing component interactions and supporting state-dependent parameters. In order to investigate the utility of this approach, a number of sample design problems from the field of aerospace engineering were implemented using the prototype design tool, Rubber Airplane. The additional level of organizational structure obtained by representing design knowledge in terms of components is observed to provide greater convenience to the program user, and to

  6. Computer-aided design of high-contact-ratio gears for minimum dynamic load and stress

    NASA Technical Reports Server (NTRS)

    Lin, Hsiang Hsi; Lee, Chinwai; Oswald, Fred B.; Townsend, Dennis P.

    1990-01-01

    A computer aided design procedure is presented for minimizing dynamic effects on high contact ratio gears by modification of the tooth profile. Both linear and parabolic tooth profile modifications of high contact ratio gears under various loading conditions are examined and compared. The effects of the total amount of modification and the length of the modification zone were systematically studied at various loads and speeds to find the optimum profile design for minimizing the dynamic load and the tooth bending stress. Parabolic profile modification is preferred over linear profile modification for high contact ratio gears because of its lower sensitivity to manufacturing errors. For parabolic modification, a greater amount of modification at the tooth tip and a longer modification zone are required. Design charts are presented for high contact ratio gears with various profile modifications operating under a range of loads. A procedure is illustrated for using the charts to find the optimum profile design.

  7. Design-based approach to ethics in computer-aided diagnosis

    NASA Astrophysics Data System (ADS)

    Collmann, Jeff R.; Lin, Jyh-Shyan; Freedman, Matthew T.; Wu, Chris Y.; Hayes, Wendelin S.; Mun, Seong K.

    1996-04-01

    A design-based approach to ethical analysis examines how computer scientists, physicians and patients make and justify choices in designing, using and reacting to computer-aided diagnosis (CADx) systems. The basic hypothesis of this research is that values are embedded in CADx systems during all phases of their development, not just retrospectively imposed on them. This paper concentrates on the work of computer scientists and physicians as they attempt to resolve central technical questions in designing clinically functional CADx systems for lung cancer and breast cancer diagnosis. The work of Lo, Chan, Freedman, Lin, Wu and their colleagues provides the initial data on which this study is based. As these researchers seek to increase the rate of true positive classifications of detected abnormalities in chest radiographs and mammograms, they explore dimensions of the fundamental ethical principal of beneficence. The training of CADx systems demonstrates the key ethical dilemmas inherent in their current design.

  8. Large Advanced Space Systems (LASS) computer-aided design program additions

    NASA Technical Reports Server (NTRS)

    Farrell, C. E.

    1982-01-01

    The LSS preliminary and conceptual design requires extensive iteractive analysis because of the effects of structural, thermal, and control intercoupling. A computer aided design program that will permit integrating and interfacing of required large space system (LSS) analyses is discussed. The primary objective of this program is the implementation of modeling techniques and analysis algorithms that permit interactive design and tradeoff studies of LSS concepts. Eight software modules were added to the program. The existing rigid body controls module was modified to include solar pressure effects. The new model generator modules and appendage synthesizer module are integrated (interfaced) to permit interactive definition and generation of LSS concepts. The mass properties module permits interactive specification of discrete masses and their locations. The other modules permit interactive analysis of orbital transfer requirements, antenna primary beam n, and attitude control requirements.

  9. Computer aided design of digital controller for radial active magnetic bearings

    NASA Astrophysics Data System (ADS)

    Cai, Zhong; Shen, Zupei; Zhang, Zuming; Zhao, Hongbin

    1992-05-01

    A five degree of freedom Active Magnetic Bearing (AMB) system is developed which is controlled by digital controllers. The model of the radial AMB system is linearized and the state equation is derived. Based on the state variables feedback theory, digital controllers are designed. The performance of the controllers are evaluated according to experimental results. The Computer Aided Design (CAD) method is used to design controllers for magnetic bearings. The controllers are implemented with a digital signal processing (DSP) system. The control algorithms are realized with real-time programs. It is very easy to change the controller by changing or modifying the programs. In order to identify the dynamic parameters of the controlled magnetic system, a special experiment was carried out. Also, the online Recursive Least Squares (RLS) parameter identification method is studied. It can be realized with the digital controllers. Online parameter identification is essential for the realization of an adaptive controller.

  10. Toward the computer-aided design of metal ion sequestering agents

    SciTech Connect

    Hay, Benjamin P.; Firman, Timothy K.; Lumetta, Gregg J.; Rapko, Brian M.; Garza, Priscilla A.; Sinkov, Sergei I.; Hutchison, James E.; Parks, Bevin W.; Gilbertson, Robert D.; Weakley, Timothy J R

    2004-07-14

    The concepts embodied in de novo structure-based drug design are being adapted for the computer-aided design of metal ion sequestering agents. This adaptation requires the development of methods for (i) generating candidate structures and (ii) evaluating and prioritizing these structures with respect to their binding affinity for a specific guest. This article summarizes recent progress in this area that includes the creation of a new computer software program, called HostDesigner, that can generate and evaluate millions of new molecular structures per minute on a desktop personal computer. Several methods for evaluating the degree of binding site organization in a host structure are presented. An example is provided to demonstrate how these methods have been used to identify ligand architectures that provide enhanced metal ion binding affinity.

  11. Computer aided design of digital controller for radial active magnetic bearings

    NASA Technical Reports Server (NTRS)

    Cai, Zhong; Shen, Zupei; Zhang, Zuming; Zhao, Hongbin

    1992-01-01

    A five degree of freedom Active Magnetic Bearing (AMB) system is developed which is controlled by digital controllers. The model of the radial AMB system is linearized and the state equation is derived. Based on the state variables feedback theory, digital controllers are designed. The performance of the controllers are evaluated according to experimental results. The Computer Aided Design (CAD) method is used to design controllers for magnetic bearings. The controllers are implemented with a digital signal processing (DSP) system. The control algorithms are realized with real-time programs. It is very easy to change the controller by changing or modifying the programs. In order to identify the dynamic parameters of the controlled magnetic system, a special experiment was carried out. Also, the online Recursive Least Squares (RLS) parameter identification method is studied. It can be realized with the digital controllers. Online parameter identification is essential for the realization of an adaptive controller.

  12. Influence of different luting protocols on shear bond strength of computer aided design/computer aided manufacturing resin nanoceramic material to dentin

    PubMed Central

    Poggio, Claudio; Pigozzo, Marco; Ceci, Matteo; Scribante, Andrea; Beltrami, Riccardo; Chiesa, Marco

    2016-01-01

    Background: The purpose of this study was to evaluate the influence of three different luting protocols on shear bond strength of computer aided design/computer aided manufacturing (CAD/CAM) resin nanoceramic (RNC) material to dentin. Materials and Methods: In this in vitro study, 30 disks were milled from RNC blocks (Lava Ultimate/3M ESPE) with CAD/CAM technology. The disks were subsequently cemented to the exposed dentin of 30 recently extracted bovine permanent mandibular incisors. The specimens were randomly assigned into 3 groups of 10 teeth each. In Group 1, disks were cemented using a total-etch protocol (Scotchbond™ Universal Etchant phosphoric acid + Scotchbond Universal Adhesive + RelyX™ Ultimate conventional resin cement); in Group 2, disks were cemented using a self-etch protocol (Scotchbond Universal Adhesive + RelyX™ Ultimate conventional resin cement); in Group 3, disks were cemented using a self-adhesive protocol (RelyX™ Unicem 2 Automix self-adhesive resin cement). All cemented specimens were placed in a universal testing machine (Instron Universal Testing Machine 3343) and submitted to a shear bond strength test to check the strength of adhesion between the two substrates, dentin, and RNC disks. Specimens were stressed at a crosshead speed of 1 mm/min. Data were analyzed with analysis of variance and post-hoc Tukey's test at a level of significance of 0.05. Results: Post-hoc Tukey testing showed that the highest shear strength values (P < 0.001) were reported in Group 2. The lowest data (P < 0.001) were recorded in Group 3. Conclusion: Within the limitations of this in vitro study, conventional resin cements (coupled with etch and rinse or self-etch adhesives) showed better shear strength values compared to self-adhesive resin cements. Furthermore, conventional resin cements used together with a self-etch adhesive reported the highest values of adhesion. PMID:27076822

  13. Fatigue analysis of computer-aided design/computer-aided manufacturing resin-based composite vs. lithium disilicate glass-ceramic.

    PubMed

    Ankyu, Shuhei; Nakamura, Keisuke; Harada, Akio; Hong, Guang; Kanno, Taro; Niwano, Yoshimi; Örtengren, Ulf; Egusa, Hiroshi

    2016-08-01

    Resin-based composite molar crowns made by computer-aided design/computer-aided manufacturing (CAD/CAM) systems have been proposed as an inexpensive alternative to metal-ceramic or all-ceramic crowns. However, there is a lack of scientific information regarding fatigue resistance. This study aimed to analyze the fatigue behavior of CAD/CAM resin-based composite compared with lithium disilicate glass-ceramic. One-hundred and sixty bar-shaped specimens were fabricated using resin-based composite blocks [Lava Ultimate (LU); 3M/ESPE] and lithium disilicate glass-ceramic [IPS e.max press (EMP); Ivoclar/Vivadent]. The specimens were divided into four groups: no treatment (NT); thermal cycling (TC); mechanical cycling (MC); and thermal cycling followed by mechanical cycling (TCMC). Thermal cycling was performed by alternate immersion in water baths of 5°C and 55°C for 5 × 10(4) cycles. Mechanical cycling was performed in a three-point bending test, with a maximum load of 40 N, for 1.2 × 10(6) cycles. In addition, LU and EMP molar crowns were fabricated and subjected to fatigue treatments followed by load-to-failure testing. The flexural strength of LU was not severely reduced by the fatigue treatments. The fatigue treatments did not significantly affect the fracture resistance of LU molar crowns. The results demonstrate the potential of clinical application of CAD/CAM-generated resin-based composite molar crowns in terms of fatigue resistance. PMID:27203408

  14. Shear bond strength of computer-aided design and computer-aided manufacturing feldspathic and nano resin ceramics blocks cemented with three different generations of resin cement

    PubMed Central

    Ab-Ghani, Zuryati; Jaafar, Wahyuni; Foo, Siew Fon; Ariffin, Zaihan; Mohamad, Dasmawati

    2015-01-01

    Aim: To evaluate the shear bond strength between the dentin substrate and computer-aided design and computer-aided manufacturing feldspathic ceramic and nano resin ceramics blocks cemented with resin cement. Materials and Methods: Sixty cuboidal blocks (5 mm × 5 mm × 5 mm) were fabricated in equal numbers from feldspathic ceramic CEREC® Blocs PC and nano resin ceramic Lava™ Ultimate, and randomly divided into six groups (n = 10). Each block was cemented to the dentin of 60 extracted human premolar using Variolink® II/Syntac Classic (multi-steps etch-and-rinse adhesive bonding), NX3 Nexus® (two-steps etch-and-rinse adhesive bonding) and RelyX™ U200 self-adhesive cement. All specimens were thermocycled, and shear bond strength testing was done using the universal testing machine at a crosshead speed of 1.0 mm/min. Data were analyzed using one-way ANOVA. Results: Combination of CEREC® Blocs PC and Variolink® II showed the highest mean shear bond strength (8.71 Mpa), while the lowest of 2.06 Mpa were observed in Lava™ Ultimate and RelyX™ U200. There was no significant difference in the mean shear bond strength between different blocks. Conclusion: Variolink® II cement using multi-steps etch-and-rinse adhesive bonding provided a higher shear bond strength than the self-adhesive cement RelyX U200. The shear bond strength was not affected by the type of blocks used. PMID:26430296

  15. Current Status of Computer-Aided Drug Design for Type 2 Diabetes

    PubMed Central

    Bibi, Shabana; Sakata, Katsumi

    2016-01-01

    Background Diabetes is a metabolic disorder that requires multiple therapeutic approaches. The pancreas loses its functionality to properly produce the insulin hormone in patients with diabetes mellitus. In 2012, more than one million people worldwide died as a result of diabetes, which was the eighth leading cause of death. Objective Most drugs currently available and approved by the U.S. Food and Drug Administration cannot reach an adequate level of glycemic control in diabetic patients, and have many side effects; thus, new classes of compounds are required. Efforts based on computer-aided drug design (CADD) can mine a large number of databases to produce new and potent hits and minimize the requirement of time and dollars for new discoveries. Methods Pharmaceutical sciences have made progress with advances in drug design concepts. Virtual screening of large databases is most compatible with different computational methods such as molecular docking, pharmacophore, quantitative structure-activity relationship, and molecular dynamic simulation. Contribution of these methods in selection of antidiabetic compounds has been discussed. Results The Computer-Aided Drug Design (CADD) approach has contributed to successful discovery of novel anti-diabetic agents. This mini-review focuses on CADD approach on currently approved drugs and new therapeutic agents-in-development that may achieve suitable glucose levels and decrease the risk of hypoglycemia, which is a major obstacle to glucose control and a special concern for therapies that increase insulin levels. Conclusion Drug design and development for type 2 diabetes have been actively studied. However, a large number of antidiabetic drugs are still in early stages of development. The conventional target- and structure-based approaches can be regarded as part of the efforts toward therapeutic mechanism-based drug design for treatment of type 2 diabetes. It is expected that further improvement in CADD approach will

  16. Computer-aided design and distributed system technology development for large space structures

    NASA Technical Reports Server (NTRS)

    Armstrong, Ernest S.; Joshi, Suresh M.

    1986-01-01

    Proposed large space structures have many characteristics that make them difficult to analyze and control. They are highly flexible, with components mathematically modeled by partial differential equations or very large systems of ordinary differential equations. They have many resonant frequencies, typically low and closely spaced. Natural damping may be low and/or improperly modeled. Coupled with stringent operational requirements of orientation, shape control, and vibration suppression, and the inability to perform adequate ground testing, these characteristics present an unconventional identification and control design problem to the systems theorist. Some of the research underway within Langley's Spacecraft Control Branch, Guidance and Control Division aimed at developing theory and algorithms to treat large space structures systems identification and control problems is described. The research areas to be considered are computer-aided design algorithms, and systems identification and control of distributed systems.

  17. Computer aided design and manufacturing of composite propfan blades for a cruise missile wind tunnel model

    NASA Technical Reports Server (NTRS)

    Thorp, Scott A.; Downey, Kevin M.

    1992-01-01

    One of the propulsion concepts being investigated for future cruise missiles is advanced unducted propfans. To support the evaluation of this technology applied to the cruise missile, a joint DOD and NASA test project was conducted to design and then test the characteristics of the propfans on a 0.55-scale, cruise missile model in a NASA wind tunnel. The configuration selected for study is a counterrotating rearward swept propfan. The forward blade row, having six blades, rotates in a counterclockwise direction, and the aft blade row, having six blades, rotates in a clockwise direction, as viewed from aft of the test model. Figures show the overall cruise missile and propfan blade configurations. The objective of this test was to evaluate propfan performance and suitability as a viable propulsion option for next generation of cruise missiles. This paper details the concurrent computer aided design, engineering, and manufacturing of the carbon fiber/epoxy propfan blades as the NASA Lewis Research Center.

  18. Computer-aided design system with artificial intelligence for automatic dimensioning

    SciTech Connect

    Huang, R.; Juricic, D.

    1995-12-31

    This paper is concerned with the methodology applicable to automating computer drafting tasks of a Computer-Aided Drafting and Design (CADD) system. One of the main characteristics of these tasks is the need for interaction with geometric models and their features. The specific drafting task considered in this paper was dimensioning of a multiview drawing. The paper illustrates the approach used and describes the introduction of relevant knowledge base as well as implementation of an inference engine internal to the drafting system. A simple class of objects was used to illustrate in more details the methods involved. It is noted that developing this methodology may be of vital importance for further automation of the drafting and design process.

  19. Automated a complex computer aided design concept generated using macros programming

    NASA Astrophysics Data System (ADS)

    Rizal Ramly, Mohammad; Asrokin, Azharrudin; Abd Rahman, Safura; Zulkifly, Nurul Ain Md

    2013-12-01

    Changing a complex Computer Aided design profile such as car and aircraft surfaces has always been difficult and challenging. The capability of CAD software such as AutoCAD and CATIA show that a simple configuration of a CAD design can be easily modified without hassle, but it is not the case with complex design configuration. Design changes help users to test and explore various configurations of the design concept before the production of a model. The purpose of this study is to look into macros programming as parametric method of the commercial aircraft design. Macros programming is a method where the configurations of the design are done by recording a script of commands, editing the data value and adding a certain new command line to create an element of parametric design. The steps and the procedure to create a macro programming are discussed, besides looking into some difficulties during the process of creation and advantage of its usage. Generally, the advantages of macros programming as a method of parametric design are; allowing flexibility for design exploration, increasing the usability of the design solution, allowing proper contained by the model while restricting others and real time feedback changes.

  20. Computer-aided design of control systems to meet many requirements

    NASA Technical Reports Server (NTRS)

    Schy, A. A.; Adams, W. M., Jr.; Johnson, K. G.

    1974-01-01

    A method is described for using nonlinear programing in the computer-aided design of airplane control systems. It is assumed that the quality of such systems depends on many criteria. These criteria are included in the constraints vector (instead of attempting to combine them into a single scalar criterion, as is usually done), and the design proceeds through a sequence of nonlinear programing solutions in which the designer varies the specification of sets of requirements levels. The method is applied to design of a lateral stability augmentation system (SAS) for a fighter airplane, in which the requirements vector is chosen from the official handling qualities specifications. Results are shown for several simple SAS configurations designed to obtain desirable handling qualities over all design flight conditions with minimum feedback gains. The choice of the final design for each case is not unique but depends on the designer's decision as to which achievable set of requirements levels represents the best for that system. Results indicate that it may be possible to design constant parameter SAS which can satisfy the most stringent handling qualities requirements for fighter airplanes in all flight conditions. The role of the designer as a decision maker, interacting with the computer program, is discussed. Advantages of this type of designer-computer interaction are emphasized. Desirable extensions of the method are indicated.

  1. Computer aided solar house design made of ``Guadua`` in Bogota, Colombia

    SciTech Connect

    Lozano, M.C.; Chalfoun, N.V.

    1995-11-01

    Bogota, Colombia, is the third highest capital in South America, its location near the equator assures high altitudes over the horizon and almost 5 hours of daily mean sunshine. Since 1981, efforts for using natural energy instead of nonrenewable fuel have been targeted to Colombia`s residential construction industry. This paper focuses on a computer aided design process for passive solar low-income row housing in Bogota. Thermal comfort for this tropical climate has been achieved through employing ``Guadua,`` a strong bamboo specie,as an alternative wall system to the traditional brick, adobe, or concrete structures. Through computer analysis, several energy conservation and passive solar strategies have been optimized for a case study row housing type common to the region. The load savings compared to a 6 inch CMU house totaled 72%, while the operating cost has been reduced by 71%. Furthermore, this lightweight and inexpensive ``Guadua`` material has reduced the construction cost by 30%.

  2. Alzheimer's disease drug development based on Computer-Aided Drug Design.

    PubMed

    Zeng, Huahui; Wu, Xiangxiang

    2016-10-01

    Alzheimer's disease (AD) is a common neurodegenerative disorder characterized by the excessive deposition of amyloids in the brain. The pathological features mainly include the extracellular amyloid plaques and intracellular neurofibrillary tangles, which are the production of amyloid precursor protein (APP) processed by the α-, β- and γ-secretases. Based on the amyloid cascade hypotheses of AD, a large number of amyloid-β agents and secretase inhibitors against AD have been recently developed by using computational methods. This review article describes pathophysiology of AD and the structure of the Aβ plaques, β- and γ-secretases, and discusses the recent advances in the development of the amyloid agents for AD therapy and diagnosis by using Computer-Aided Drug Design approach. PMID:26415837

  3. Biomechanical stresses in computer-aided design and in data entry.

    PubMed

    Cail, François; Aptel, Michel

    2003-01-01

    A study of the risk factors of musculoskeletal disorders (MSDs) of the upper limbs was carried out on 2 populations, 1 performing a computer-aided design (CAD) task and the other performing a data entry task. A questionnaire on MSD complaints and working life was completed by a sample of each population. Biomechanical measurements of the forces, the angles, and the repetitiveness of movements of the upper limbs were carried out on some operators in each sample. It emerged that complaints of the upper limbs seem to be linked to the use of input devices. The grip forces exerted when using the keyboard and mouse were higher in CAD than in data entry. PMID:14577943

  4. Selection and implementation of a computer aided design and drafting (CAD/D) system

    SciTech Connect

    Davis, J.P.

    1981-01-01

    Faced with very heavy workloads and limited engineering and graphics personnel, Transco opted for a computer-aided design and drafting system that can produce intelligent drawings, which have associated data bases that can be integrated with other graphical and nongraphical data bases to form comprehensive sets of data for construction projects. Because so much time was being spent in all phases of materials and inventory control, Transco decided to integrate materials-management capabilities into the CAD/D system. When a specific item of material is requested on the graphics equipment, the request triggers production of both the drawing and a materials list. Transco plans to extend its computer applications into mapping tasks as well.

  5. Facility management of computer-aided design, drafting/manufacturing systems (CADD/M)

    SciTech Connect

    Norton, F.J.

    1980-09-23

    Interactive Computer-Aided Design Drafting/Manufacturing systems have been installed in thousands of companies, applying CADD/M capabilities to many applications. This has been done with varying degrees of success even among companies with identical applications. Investigation of individual companies reveals a gap between the capabilities of CADD/M systems and the actual usage by industry of those capabilities. This company usage often determines the degree of success or failure of an interactive graphics facility and is largely controlled by management. The responsibilities of the interactive graphics facility managemant team are explained in detail. Proper management of a CADD/M facility is more critical to the success or failure of the facility than any other factor.

  6. Cost justification for an interactive Computer-Aided Design Drafting/Manufacturing system

    SciTech Connect

    Norton, F.J.

    1980-09-23

    Many factors influence the capital investment decision. System costs and benefits are weighed by methods of financial analysis to determine the advisability of an investment. Capital, expense, and benefits as related to Interactive Computer-Aided Design Drafting/Manufacturing (CADD/M) Systems are discussed and model calculations are included. An example is treated by the simple payback method and the more sophisticated methods of Net Present Value (NPV) and Internal Rate of Return (IRR). The NPV and IRR approaches include in the calculation the time value of money and provide a sounder foundation on which to base the purchase decision. It is hoped that an understanding of these techniques by technical personnel will make an optimum system purchase more likely.

  7. User's manual: Computer-aided design programs for inductor-energy-storage dc-to-dc electronic power converters

    NASA Technical Reports Server (NTRS)

    Huffman, S.

    1977-01-01

    Detailed instructions on the use of two computer-aided-design programs for designing the energy storage inductor for single winding and two winding dc to dc converters are provided. Step by step procedures are given to illustrate the formatting of user input data. The procedures are illustrated by eight sample design problems which include the user input and the computer program output.

  8. GA-Based Computer-Aided Electromagnetic Design of Two-Phase SRM for Compressor Drives

    NASA Astrophysics Data System (ADS)

    Kano, Yoshiaki; Kosaka, Takashi; Matsui, Nobuyuki

    This paper presents an approach to Genetic Algorithm (GA)-based computer-aided autonomous electromagnetic design of 2-phase Switched Reluctance Motor drives. The proposed drive is designed for compressor drives in low-priced refrigerators as an alternative to existing brushless DC motors drives with rare-earth magnets. In the proposed design approach, three GA loops work to optimize the lamination design so as to meet the requirements for the target application under the given constraints while simultaneously fine-tuning the control parameters. To achieve the design optimization within an acceptable CPU-time, the repeated-calculation required to obtain fitness evaluation in the proposed approach does not use FEM, but consists of geometric flux tube-based non-linear magnetic analysis and a dynamic simulator based on an analytical expression of the magnetizing curves obtained from the non-linear magnetic analysis. The design results show the proposed approach can autonomously find a feasible design solution of SRM drive for the target application from huge search space. The experimental studies using a 2-phase 8/6 prototype manufactured in accordance with the optimized design parameters show the validity of the proposed approach.

  9. Computer-aided design comparisons of monolithic and hybrid MEM-tunable VCSELs

    NASA Astrophysics Data System (ADS)

    Ochoa, Edward M.; Nelson, Thomas R., Jr.; Blum-Spahn, Olga; Lott, James A.

    2003-07-01

    We report and use our micro-electro-mechanically tunable vertical cavity surface emitting laser (MEM-TVCSEL) computer-aided design methodology to investigate the resonant frequency design space for monolithic and hybrid MEM-TVCSELs. For various initial optical air gap thickness, we examine the sensitivity of monolithic or hybrid MEM-TVCSEL resonant frequency by simulating zero, two, and four percent variations in III-V material growth thickness. As expected, as initial optical airgap increases, tuning range decreases due to less coupling between the active region and the tuning mirror. However, each design has different resonant frequency sensitivity to variations in III-V growth parameters. In particular, since the monolithic design is comprised of III-V material, the shift in all growth thicknesses significantly shifts the resonant frequency response. However, for hybrid MEMTVCSELs, less shift results, since the lower reflector is an Au mirror with reflectivity independent of III-V growth variations. Finally, since the hybrid design is comprised of a MUMPS polysilicon mechanical actuator, pull-in voltage remains independent of the initial optical airgap between the tuning reflector and the III-V material. Conversely, as the initial airgap increases in the monolithic design, the pull-in voltage significantly increases.

  10. Designing optimal transportation networks: a knowledge-based computer-aided multicriteria approach

    SciTech Connect

    Tung, S.I.

    1986-01-01

    The dissertation investigates the applicability of using knowledge-based expert systems (KBES) approach to solve the single-mode (automobile), fixed-demand, discrete, multicriteria, equilibrium transportation-network-design problem. Previous works on this problem has found that mathematical programming method perform well on small networks with only one objective. Needed is a solution technique that can be used on large networks having multiple, conflicting criteria with different relative importance weights. The KBES approach developed in this dissertation represents a new way to solve network design problems. The development of an expert system involves three major tasks: knowledge acquisition, knowledge representation, and testing. For knowledge acquisition, a computer aided network design/evaluation model (UFOS) was developed to explore the design space. This study is limited to the problem of designing an optimal transportation network by adding and deleting capacity increments to/from any link in the network. Three weighted criteria were adopted for use in evaluating each design alternative: cost, average V/C ratio, and average travel time.

  11. Interface between a printed circuit board computer aided design tool (Tektronix 4051 based) and a numerical paper tape controlled drill press (Slo-Syn 530: 100 w/ Dumore Automatic Head Number 8391)

    SciTech Connect

    Heckman, B.K.; Chinn, V.K.

    1981-01-01

    The development and use of computer programs written to produce the paper tape needed for the automation, or numeric control, of drill presses employed to fabricate computed-designed printed circuit boards are described. (LCL)

  12. Using GREENSCOPE Indicators for Sustainable Computer-Aided Process Evaluation and Design

    EPA Science Inventory

    Manufacturing sustainability can be increased by educating those who design, construct, and operate facilities, and by using appropriate tools for process evaluation and design. The U.S. Environmental Protection Agency's GREENSCOPE methodology and tool, for evaluation and design ...

  13. Effect of different adhesive strategies on microtensile bond strength of computer aided design/computer aided manufacturing blocks bonded to dentin

    PubMed Central

    Roperto, Renato; Akkus, Anna; Akkus, Ozan; Lang, Lisa; Sousa-Neto, Manoel Damiao; Teich, Sorin; Porto, Thiago Soares

    2016-01-01

    Background: The aim of this study was to determine the microtensile bond strength (μTBS) of ceramic and composite computer aided design-computer aided manufacturing (CAD-CAM) blocks bonded to dentin using different adhesive strategies. Materials and Methods: In this in vitro study, 30 crowns of sound freshly extracted human molars were sectioned horizontally 3 mm above the cementoenamel junction to produce flat dentin surfaces. Ceramic and composite CAD/CAM blocks, size 14, were sectioned into slices of 3 mm thick. Before bonding, CAD/CAM block surfaces were treated according to the manufacturer's instructions. Groups were created based on the adhesive strategy used: Group 1 (GI) - conventional resin cement + total-etch adhesive system, Group 2 (GII) - conventional resin cement + self-etch adhesive system, and Group 3 (GIII) - self-adhesive resin cement with no adhesive. Bonded specimens were stored in 100% humidity for 24h at 37΀C, and then sectioned with a slow-speed diamond saw to obtain 1 mm × 1 mm × 6 mm microsticks. Microtensile testing was then conducted using a microtensile tester. μTBS values were expressed in MPa and analyzed by one-way ANOVA with post hoc (Tukey) test at the 5% significance level. Results: Mean values and standard deviations of μTBS (MPa) were 17.68 (±2.71) for GI/ceramic; 17.62 (±3.99) for GI/composite; 13.61 (±6.92) for GII/composite; 12.22 (±4.24) for GII/ceramic; 7.47 (±2.29) for GIII/composite; and 6.48 (±3.10) for GIII/ceramic; ANOVA indicated significant differences among the adhesive modality and block interaction (P < 0.05), and no significant differences among blocks only, except between GI and GII/ceramic. Bond strength of GIII was consistently lower (P < 0.05) than GI and GII groups, regardless the block used. Conclusion: Cementation of CAD/CAM restorations, either composite or ceramic, can be significantly affected by different adhesive strategies used. PMID:27076825

  14. NEXUS/NASCAD- NASA ENGINEERING EXTENDIBLE UNIFIED SOFTWARE SYSTEM WITH NASA COMPUTER AIDED DESIGN

    NASA Technical Reports Server (NTRS)

    Purves, L. R.

    1994-01-01

    NEXUS, the NASA Engineering Extendible Unified Software system, is a research set of computer programs designed to support the full sequence of activities encountered in NASA engineering projects. This sequence spans preliminary design, design analysis, detailed design, manufacturing, assembly, and testing. NEXUS primarily addresses the process of prototype engineering, the task of getting a single or small number of copies of a product to work. Prototype engineering is a critical element of large scale industrial production. The time and cost needed to introduce a new product are heavily dependent on two factors: 1) how efficiently required product prototypes can be developed, and 2) how efficiently required production facilities, also a prototype engineering development, can be completed. NEXUS extendibility and unification are achieved by organizing the system as an arbitrarily large set of computer programs accessed in a common manner through a standard user interface. The NEXUS interface is a multipurpose interactive graphics interface called NASCAD (NASA Computer Aided Design). NASCAD can be used to build and display two and three-dimensional geometries, to annotate models with dimension lines, text strings, etc., and to store and retrieve design related information such as names, masses, and power requirements of components used in the design. From the user's standpoint, NASCAD allows the construction, viewing, modification, and other processing of data structures that represent the design. Four basic types of data structures are supported by NASCAD: 1) three-dimensional geometric models of the object being designed, 2) alphanumeric arrays to hold data ranging from numeric scalars to multidimensional arrays of numbers or characters, 3) tabular data sets that provide a relational data base capability, and 4) procedure definitions to combine groups of system commands or other user procedures to create more powerful functions. NASCAD has extensive abilities to

  15. Use of CADD (Computer Aided Drafting and Design) in a construction setting

    SciTech Connect

    Ketcham, D.L.

    1988-01-01

    At the outset of the design for the Defense Waste Processing Facility (DWPF) it was determined to complete over 70 percent of the more than 7000 drawings on a Computer Aided Drafting and Design (CADD) system. This ambitious goal required the development of an integrated data base for plant design software systems to service a multi-discipline, engineering and management environment for the complex one-of-a-kind mega project. The implementation involved extensive training, special accounting and security provisions to meet QA requirements. It was found to be effective to train engineers as well as operators so that technical personnel could have direct access to the drawing files. This was particularly useful when designing and laying out close tolerance equipment in remotely maintained cells where clearances are critical. It was also beneficial to have the terminals located in the same areas as the engineering staff. Background drawings were maintained by one discipline and used as a reference file by the other disciplines. This reduced the chances of interferences and insured that the latest revisions were in use. 2 figs.

  16. Interactive computer aided design of electric machines and electromagnetic apparatus (invited)

    NASA Astrophysics Data System (ADS)

    Freeman, E. M.

    1982-11-01

    The design of electromagnetic devices in industry is still largely done using traditional techniques. Early computing facilities were costly to use and limited to alphanumeric applications. The application of numerical methods, mainly finite elements, to the solution of electromagnetic field problems, proved to be difficult to implement initially due to input/output problems. These difficulties were completely obviated by the advent of inexpensive microcomputers and low cost interactive graphics. However, it is still uncommon to find these new methods being employed as part of the normal electrical design process. Meanwhile, in parallel, there has been a massive growth of computer-aided methods applied to all aspects of mechanical engineering design and drafting, CADCAM. The trend is towards small, powerful, expandable, dedicated computer systems equipped with high resolution interactive graphics, which can be connected via a fast datalink. These are commonly available, complete with software, as turnkey systems. The advantages of CADCAM are manifold: Lower costs, higher productivity, higher quality products, with shorter lead times. The introduction of CADCAM will result in organisational as well as technical changes. The major change will be in the way people think.

  17. 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. PMID:23651478

  18. Effectiveness of using CADD (Computer-Aided Design Drafting) to learn engineering design graphics

    SciTech Connect

    Bertoline, G.R.

    1987-01-01

    One commercial CADD software and one educational CADD software was compared to the use of traditional tools. Engineering-graphics students were divided into three groups. The control group used traditional tools for all their drawings. One experimental group used a commercial CADD software to supplement hand tools and one group used an educational CADD software to supplement traditional tools. These groups were then post-tested using a standardized drafting test. The main findings were: (1) There was no significant difference in the learning of engineering graphics as measured by the post-tests. Supplementing traditional tools with CADD is effective for teaching engineering design graphics. (2) Using CADD for detail drawings such as simple orthographic drawings, sections, and dimensions could be produced in approximately the same amount of time as using traditional tools. (3) It was found that the amount of time needed to solve descriptive geometry problems using CADD was prohibitive. The amount of time to solve some descriptive geometry problems was two or three times greater using CADD versus traditional tools.

  19. Computer-aided roll pass design in rolling of airfoil shapes

    NASA Technical Reports Server (NTRS)

    Akgerman, N.; Lahoti, G. D.; Altan, T.

    1980-01-01

    This paper describes two computer-aided design (CAD) programs developed for modeling the shape rolling process for airfoil sections. The first program, SHPROL, uses a modular upper-bound method of analysis and predicts the lateral spread, elongation, and roll torque. The second program, ROLPAS, predicts the stresses, roll separating force, the roll torque and the details of metal flow by simulating the rolling process, using the slab method of analysis. ROLPAS is an interactive program; it offers graphic display capabilities and allows the user to interact with the computer via a keyboard, CRT, and a light pen. The accuracy of the computerized models was evaluated by (a) rolling a selected airfoil shape at room temperature from 1018 steel and isothermally at high temperature from Ti-6Al-4V, and (b) comparing the experimental results with computer predictions. The comparisons indicated that the CAD systems, described here, are useful for practical engineering purposes and can be utilized in roll pass design and analysis for airfoil and similar shapes.

  20. Computer-aided design of dry powder inhalers using computational fluid dynamics to assess performance.

    PubMed

    Suwandecha, Tan; Wongpoowarak, Wibul; Srichana, Teerapol

    2016-01-01

    Dry powder inhalers (DPIs) are gaining popularity for the delivery of drugs. A cost effective and efficient delivery device is necessary. Developing new DPIs by modifying an existing device may be the simplest way to improve the performance of the devices. The aim of this research was to produce a new DPIs using computational fluid dynamics (CFD). The new DPIs took advantages of the Cyclohaler® and the Rotahaler®. We chose a combination of the capsule chamber of the Cyclohaler® and the mouthpiece and grid of the Rotahaler®. Computer-aided design models of the devices were created and evaluated using CFD. Prototype models were created and tested with the DPI dispersion experiments. The proposed model 3 device had a high turbulence with a good degree of deagglomeration in the CFD and the experiment data. The %fine particle fraction (FPF) was around 50% at 60 L/min. The mass median aerodynamic diameter was around 2.8-4 μm. The FPF were strongly correlated to the CFD-predicted turbulence and the mechanical impaction parameters. The drug retention in the capsule was only 5-7%. In summary, a simple modification of the Cyclohaler® and Rotahaler® could produce a better performing inhaler using the CFD-assisted design. PMID:25265389

  1. Computer-aided design drafting/manufacturing (CADD/M) facility preparation

    SciTech Connect

    Norton, F.J.

    1980-09-23

    Computer-Aided Design, Drafting and Manufacturing (CADD/M) equipment requires careful facilities preparation before installation takes place. This paper presents what a company should consider to ensure a proper installation. This includes consideration of working conditions. To get the most out of the system, the operators must be provided with a relaxed, comfortable environment, free from noise and other distractions. Such things as temperature requirements, lighting, power, security and fire protection are discussed. Also, future expansion needs are considered so that major construction will not be required for future years. Advanced planning in these areas is needed to ensure successful implementation of a CADD/M system. This will lead to considerable cost savings, and in the long run, improve the scheduling for an entire project, from initial design to final production. This careful preparation will minimize unplanned events and problem areas. These are ambitious goals but easily realized if a logical and rational plan is adopted in the same manner as that used in a typical development program.

  2. Design, Development, Implementation, and Evaluation of the Computer Aided Interactive Testing System (CAITS). Focus on the Trained Person.

    ERIC Educational Resources Information Center

    1983

    This report describes the design, development, implementation, and evaluation of the Computer Aided Interactive Testing System (CAITS) and addresses the applicability of the system in the Naval Education and Training Command. In addition to an introduction (section one), the report contains four sections and three appendices. Section two describes…

  3. Revision of Electro-Mechanical Drafting Program to Include CAD/D (Computer-Aided Drafting/Design). Final Report.

    ERIC Educational Resources Information Center

    Snyder, Nancy V.

    North Seattle Community College decided to integrate computer-aided design/drafting (CAD/D) into its Electro-Mechanical Drafting Program. This choice necessitated a redefinition of the program through new curriculum and course development. To initiate the project, a new industrial advisory council was formed. Major electronic and recruiting firms…

  4. Computers in engineering 1983; Proceedings of the International Conference and Exhibit, Chicago, IL, August 7-11, 1983. Volume 1 - Computer-aided design, manufacturing, and simulation

    NASA Astrophysics Data System (ADS)

    Cokonis, T. J.

    The papers presented in this volume provide examples of the impact of computers on present engineering practice and indicate some future trends in computer-aided design, manufacturing, and simulation. Topics discussed include computer-aided design of turbine cycle configuration, managing and development of engineering computer systems, computer-aided manufacturing with robots in the automotive industry, and computer-aided design/analysis techniques of composite materials in the cure phase. Papers are also presented on computer simulation of vehicular propulsion systems, the performance of a hydraulic system simulator in a CAD environment, and computer simulation of hovercraft heave dynamics and control.

  5. Impact of computer-aided design and drafting on operator perceptions and performance intentions

    SciTech Connect

    Mandeville, D.E.

    1987-01-01

    The goal of the introduction of computer-aided design and drafting (CADD) technology is to improve engineering quantity and quality outcomes. What is not so obvious is that the manner in which the operator views the CADD job may affect these outcomes. The study found that: (1) the subjects hold job characteristic beliefs about their jobs that are similar to those held by individuals in related professional and technical positions in other organizations; (2) subjects in routine jobs who had little experience with CADD believe that the characteristics of the job with CADD will be less desirable than there present job utilizing manual drafting; however, experienced users believe that there is little difference; (3) the subjects performing technologically routine jobs indicate that quantity and quality of their jobs decreases with CADD, while holders of technologically nonroutine jobs indicate the opposite; (4) significant but weak relationships existed between job characteristic beliefs, attitudes, and job intentions; however, the model relationships and strengths varied when subgroups were analyzed; and (5) the correlation of social referent group beliefs with subject beliefs are significant but weak.

  6. Indications for Computer-Aided Design and Manufacturing in Congenital Craniofacial Reconstruction.

    PubMed

    Fisher, Mark; Medina, Miguel; Bojovic, Branko; Ahn, Edward; Dorafshar, Amir H

    2016-09-01

    The complex three-dimensional relationships in congenital craniofacial reconstruction uniquely lend themselves to the ability to accurately plan and model the result provided by computer-aided design and manufacturing (CAD/CAM). The goal of this study was to illustrate indications where CAD/CAM would be helpful in the treatment of congenital craniofacial anomalies reconstruction and to discuss the application of this technology and its outcomes. A retrospective review was performed of all congenital craniofacial cases performed by the senior author between 2010 and 2014. Cases where CAD/CAM was used were identified, and illustrative cases to demonstrate the benefits of CAD/CAM were selected. Preoperative appearance, computerized plan, intraoperative course, and final outcome were analyzed. Preoperative planning enabled efficient execution of the operative plan with predictable results. Risk factors which made these patients good candidates for CAD/CAM were identified and compiled. Several indications, including multisuture and revisional craniosynostosis, facial bipartition, four-wall box osteotomy, reduction cranioplasty, and distraction osteogenesis could benefit most from this technology. We illustrate the use of CAD/CAM for these applications and describe the decision-making process both before and during surgery. We explore why we believe that CAD/CAM is indicated in these scenarios as well as the disadvantages and risks. PMID:27516839

  7. [Numerical finite element modeling of custom car seat using computer aided design].

    PubMed

    Huang, Xuqi; Singare, Sekou

    2014-02-01

    A good cushion can not only provide the sitter with a high comfort, but also control the distribution of the hip pressure to reduce the incidence of diseases. The purpose of this study is to introduce a computer-aided design (CAD) modeling method of the buttocks-cushion using numerical finite element (FE) simulation to predict the pressure distribution on the buttocks-cushion interface. The buttock and the cushion model geometrics were acquired from a laser scanner, and the CAD software was used to create the solid model. The FE model of a true seated individual was developed using ANSYS software (ANSYS Inc, Canonsburg, PA). The model is divided into two parts, i.e. the cushion model made of foam and the buttock model represented by the pelvis covered with a soft tissue layer. Loading simulations consisted of imposing a vertical force of 520N on the pelvis, corresponding to the weight of the user upper extremity, and then solving iteratively the system. PMID:24804486

  8. Selecting and implementing an interactive Computer Aided Design Drafting/Manufacturing (CADD/M) system

    SciTech Connect

    Norton, F.J.

    1980-09-23

    Success with Interactive Computer-Aided Design Drafting/Manufacturing (CADD/M) depends upon management, users, and the system itself. If you are in a design and drafting environment, the thought of acquiring a CADD/M system will probably occur to you sometime in the very near future - if it hasn't already. Convincing yourself and your management of the benefits of such systems is but the first step. Evaluating and selecting one particular type of CADD/M system can turn out to be a complicated undertaking - not to mention somewhat frustrating. Procedures for selecting and successfully implementing a CADD/M system are outlined. INITIAL PREPARATION examines the techniques used to evaluate CADD/M systems including formation of an evaluation team, and application analysis. GRAPHICS EVALUATION describes the methods that can be used to test a CADD/M system, including benchmark drawings and specifications, human engineering considerations, and other evaluation criteria and general system configurations are also discussed. COMPUTER SYSTEM EVALUATION examines other factors in systems selection: programming, communications, documentation, and service. SYSTEM STARTUP addresses site preparation, people preparation, system acceptance, and operator, designer/drafter selection. Finally, operator, designer/drafter TRAINING and SYSTEM MANAGEMENT are discussed. This systematic approach wil help those contemplating the acquisition of CADD/M systems for their activities and will help minimize unplanned events and problem areas.Advanced planning in these areas is needed to ensure successful implementation of a CADD/M system. This in turn will lead to considerable cost savings and schedule improvements for an entire project, from initial design to final production. These are ambitious goals but easily realized if a logical and rational plan is adopted in the same manner as that used in a typical development program.

  9. Computer Aided Manufacturing.

    ERIC Educational Resources Information Center

    Insolia, Gerard

    This document contains course outlines in computer-aided manufacturing developed for a business-industry technology resource center for firms in eastern Pennsylvania by Northampton Community College. The four units of the course cover the following: (1) introduction to computer-assisted design (CAD)/computer-assisted manufacturing (CAM); (2) CAM…

  10. Computer Aided Art Major.

    ERIC Educational Resources Information Center

    Gibson, Jim

    The Computer Aided Art program offered at Northern State State University (Aberdeen, South Dakota), is coordinated with the traditional art major. The program is designed to familiarize students with a wide range of art-related computer hardware and software and their applications and to prepare students for problem-solving with unfamiliar…

  11. A method of computer aided design with self-generative models in NX Siemens environment

    NASA Astrophysics Data System (ADS)

    Grabowik, C.; Kalinowski, K.; Kempa, W.; Paprocka, I.

    2015-11-01

    Currently in CAD/CAE/CAM systems it is possible to create 3D design virtual models which are able to capture certain amount of knowledge. These models are especially useful in an automation of routine design tasks. These models are known as self-generative or auto generative and they can behave in an intelligent way. The main difference between the auto generative and fully parametric models consists in the auto generative models ability to self-organizing. In this case design model self-organizing means that aside from the possibility of making of automatic changes of model quantitative features these models possess knowledge how these changes should be made. Moreover they are able to change quality features according to specific knowledge. In spite of undoubted good points of self-generative models they are not so often used in design constructional process which is mainly caused by usually great complexity of these models. This complexity makes the process of self-generative time and labour consuming. It also needs a quite great investment outlays. The creation process of self-generative model consists of the three stages it is knowledge and information acquisition, model type selection and model implementation. In this paper methods of the computer aided design with self-generative models in NX Siemens CAD/CAE/CAM software are presented. There are the five methods of self-generative models preparation in NX with: parametric relations model, part families, GRIP language application, knowledge fusion and OPEN API mechanism. In the paper examples of each type of the self-generative model are presented. These methods make the constructional design process much faster. It is suggested to prepare this kind of self-generative models when there is a need of design variants creation. The conducted research on assessing the usefulness of elaborated models showed that they are highly recommended in case of routine tasks automation. But it is still difficult to distinguish

  12. An Analysis of Computer Aided Design (CAD) Packages Used at MSFC for the Recent Initiative to Integrate Engineering Activities

    NASA Technical Reports Server (NTRS)

    Smith, Leigh M.; Parker, Nelson C. (Technical Monitor)

    2002-01-01

    This paper analyzes the use of Computer Aided Design (CAD) packages at NASA's Marshall Space Flight Center (MSFC). It examines the effectiveness of recent efforts to standardize CAD practices across MSFC engineering activities. An assessment of the roles played by management, designers, analysts, and manufacturers in this initiative will be explored. Finally, solutions are presented for better integration of CAD across MSFC in the future.

  13. Report on DOE - industry workshop on Computer-Aided Catalyst Design (CACD)

    SciTech Connect

    Hay, P.J.

    1994-07-01

    Representatives from industry, national laboratories, and the DOE met to review the status of the DOE-sponsored Computer-Aided Catalyst Design (CACD) program and to assess current industrial needs in CACD. Of the 40 participants at the workshop, nearly half were from industry representing 12 companies--Arco Chemical, Amoco Chemical, Biosym, Dow, DuPont, Exxon, Ford, General Motors, Mobil, Monsanto, W.R. Grace and Union Carbide--that included nine of the largest chemical producers in the U.S. representing $61 billion in chemical sales in 1993. An overview of developments in catalyst modeling at the national laboratories was presented, and current CACD-related activities at each of the companies were described by the industrial participants. The CACD program is addressing important industry needs and is having a significant impact despite the current limited scope and budget. The industrial participants urged the program to continue to target specific areas and to encourage collaborative work among the national labs. Industrial participants expressed strong interest in increased interactions with CACD activities at the national labs, where competencies in theory, modeling, and simulation complement the traditional strengths of catalysis expertise in industry. The chemical, refining and automotive industries face continual economic and environmental pressures for now or improved catalytic processes that are more efficient and produce fewer undesirable byproducts. CACD is viewed as an effective means to enhance experimental catalysis research. The industrial participants attested to the importance of developing and applying catalysis modeling capabilities. The companies represented at the meeting had varying degrees of activity in this area, and many already had significant interactions with national labs. As potential users of this technology, they strongly endorsed the work in the CACD program in the development of modeling capabilities.

  14. Enveloped viruses understood via multiscale simulation: computer-aided vaccine design

    NASA Astrophysics Data System (ADS)

    Shreif, Z.; Adhangale, P.; Cheluvaraja, S.; Perera, R.; Kuhn, R.; Ortoleva, P.

    Enveloped viruses are viewed as an opportunity to understand how highly organized and functional biosystems can emerge from a collection of millions of chaotically moving atoms. They are an intermediate level of complexity between macromolecules and bacteria. They are a natural system for testing theories of self-assembly and structural transitions, and for demonstrating the derivation of principles of microbiology from laws of molecular physics. As some constitute threats to human health, a computer-aided vaccine and drug design strategy that would follow from a quantitative model would be an important contribution. However, current molecular dynamics simulation approaches are not practical for modeling such systems. Our multiscale approach simultaneously accounts for the outer protein net and inner protein/genomic core, and their less structured membranous material and host fluid. It follows from a rigorous multiscale deductive analysis of laws of molecular physics. Two types of order parameters are introduced: (1) those for structures wherein constituent molecules retain long-lived connectivity (they specify the nanoscale structure as a deformation from a reference configuration) and (2) those for which there is no connectivity but organization is maintained on the average (they are field variables such as mass density or measures of preferred orientation). Rigorous multiscale techniques are used to derive equations for the order parameters dynamics. The equations account for thermal-average forces, diffusion coefficients, and effects of random forces. Statistical properties of the atomic-scale fluctuations and the order parameters are co-evolved. By combining rigorous multiscale techniques and modern supercomputing, systems of extreme complexity can be modeled.

  15. Enveloped viruses understood via multiscale simulation: computer-aided vaccine design

    NASA Astrophysics Data System (ADS)

    Shreif, Z.; Adhangale, P.; Cheluvaraja, S.; Perera, R.; Kuhn, R.; Ortoleva, P.

    2008-04-01

    Enveloped viruses are viewed as an opportunity to understand how highly organized and functional biosystems can emerge from a collection of millions of chaotically moving atoms. They are an intermediate level of complexity between macromolecules and bacteria. They are a natural system for testing theories of self-assembly and structural transitions, and for demonstrating the derivation of principles of microbiology from laws of molecular physics. As some constitute threats to human health, a computer-aided vaccine and drug design strategy that would follow from a quantitative model would be an important contribution. However, current molecular dynamics simulation approaches are not practical for modeling such systems. Our multiscale approach simultaneously accounts for the outer protein net and inner protein/genomic core, and their less structured membranous material and host fluid. It follows from a rigorous multiscale deductive analysis of laws of molecular physics. Two types of order parameters are introduced: (1) those for structures wherein constituent molecules retain long-lived connectivity (they specify the nanoscale structure as a deformation from a reference configuration) and (2) those for which there is no connectivity but organization is maintained on the average (they are field variables such as mass density or measures of preferred orientation). Rigorous multiscale techniques are used to derive equations for the order parameters dynamics. The equations account for thermal-average forces, diffusion coefficients, and effects of random forces. Statistical properties of the atomic-scale fluctuations and the order parameters are co-evolved. By combining rigorous multiscale techniques and modern supercomputing, systems of extreme complexity can be modeled.

  16. A systematic framework for computer-aided design of engineering rubber formulations

    NASA Astrophysics Data System (ADS)

    Ghosh, Prasenjeet

    This thesis considers the design of engineering rubber formulations, whose unique properties of elasticity and resilience enable diverse applications. Engineering rubber formulations are a complex mixture of different materials called curatives that includes elastomers, fillers, crosslinking agents, accelerators, activators, retarders, anti-oxidants and processing aids, where the amount of curatives must be adjusted for each application. The characterization of the final properties of the rubber in application is complex and depends on the chemical interplay between the different curatives in formulation via vulcanization chemistry. The details of the processing conditions and the thermal, deformational, and chemical environment encountered in application also have a pronounced effect on the performance of the rubber. Consequently, for much of the history of rubber as an engineering material, its recipe formulations have been developed largely by trial-and-error, rather than by a fundamental understanding. A computer-aided, systematic and automated framework for the design of such materials is proposed in this thesis. The framework requires the solution to two sub-problems: (a) the forward problem, which involves prediction of the desired properties when the formulation is known and (b) the inverse problem that requires identification of the appropriate formulation, given the desired target properties. As part of the forward model, the chemistry of accelerated sulfur vulcanization is reviewed that permits integration of the knowledge of the past five decades in the literature to answer some old questions, reconcile some of the contradicting mechanisms and present a holistic description of the governing chemistry. Based on this mechanistic chemistry, a fundamental kinetic model is derived using population balance equations. The model quantitatively describes, for the first time, the different aspects of vulcanization chemistry. Subsequently, a novel three

  17. Computer-aided engineering system for design of sequence arrays and lithographic masks

    DOEpatents

    Hubbell, Earl A.; Lipshutz, Robert J.; Morris, Macdonald S.; Winkler, James L.

    1997-01-01

    An improved set of computer tools for forming arrays. According to one aspect of the invention, a computer system is used to select probes and design the layout of an array of DNA or other polymers with certain beneficial characteristics. According to another aspect of the invention, a computer system uses chip design files to design and/or generate lithographic masks.

  18. A flexible computer aid for conceptual design based on constraint propagation and component-modeling. [of aircraft in three dimensions

    NASA Technical Reports Server (NTRS)

    Kolb, Mark A.

    1988-01-01

    The Rubber Airplane program, which combines two symbolic processing techniques with a component-based database of design knowledge, is proposed as a computer aid for conceptual design. Using object-oriented programming, programs are organized around the objects and behavior to be simulated, and using constraint propagation, declarative statements designate mathematical relationships among all the equation variables. It is found that the additional level of organizational structure resulting from the arrangement of the design information in terms of design components provides greater flexibility and convenience.

  19. A computer-aided design system geared toward conceptual design in a research environment. [for hypersonic vehicles

    NASA Technical Reports Server (NTRS)

    STACK S. H.

    1981-01-01

    A computer-aided design system has recently been developed specifically for the small research group environment. The system is implemented on a Prime 400 minicomputer linked with a CDC 6600 computer. The goal was to assign the minicomputer specific tasks, such as data input and graphics, thereby reserving the large mainframe computer for time-consuming analysis codes. The basic structure of the design system consists of GEMPAK, a computer code that generates detailed configuration geometry from a minimum of input; interface programs that reformat GEMPAK geometry for input to the analysis codes; and utility programs that simplify computer access and data interpretation. The working system has had a large positive impact on the quantity and quality of research performed by the originating group. This paper describes the system, the major factors that contributed to its particular form, and presents examples of its application.

  20. Computer-aided engineering system for design of sequence arrays and lithographic masks

    DOEpatents

    Hubbell, E.A.; Morris, M.S.; Winkler, J.L.

    1996-11-05

    An improved set of computer tools for forming arrays is disclosed. According to one aspect of the invention, a computer system is used to select probes and design the layout of an array of DNA or other polymers with certain beneficial characteristics. According to another aspect of the invention, a computer system uses chip design files to design and/or generate lithographic masks. 14 figs.

  1. Computer-aided engineering system for design of sequence arrays and lithographic masks

    DOEpatents

    Hubbell, E.A.; Lipshutz, R.J.; Morris, M.S.; Winkler, J.L.

    1997-01-14

    An improved set of computer tools for forming arrays is disclosed. According to one aspect of the invention, a computer system is used to select probes and design the layout of an array of DNA or other polymers with certain beneficial characteristics. According to another aspect of the invention, a computer system uses chip design files to design and/or generate lithographic masks. 14 figs.

  2. Computer-aided engineering system for design of sequence arrays and lithographic masks

    DOEpatents

    Hubbell, Earl A.; Morris, MacDonald S.; Winkler, James L.

    1999-01-05

    An improved set of computer tools for forming arrays. According to one aspect of the invention, a computer system (100) is used to select probes and design the layout of an array of DNA or other polymers with certain beneficial characteristics. According to another aspect of the invention, a computer system uses chip design files (104) to design and/or generate lithographic masks (110).

  3. Computer-aided engineering system for design of sequence arrays and lithographic masks

    DOEpatents

    Hubbell, E.A.; Morris, M.S.; Winkler, J.L.

    1999-01-05

    An improved set of computer tools for forming arrays is disclosed. According to one aspect of the invention, a computer system is used to select probes and design the layout of an array of DNA or other polymers with certain beneficial characteristics. According to another aspect of the invention, a computer system uses chip design files to design and/or generate lithographic masks. 14 figs.

  4. Computer-aided engineering system for design of sequence arrays and lithographic masks

    DOEpatents

    Hubbell, Earl A.; Morris, MacDonald S.; Winkler, James L.

    1996-01-01

    An improved set of computer tools for forming arrays. According to one aspect of the invention, a computer system (100) is used to select probes and design the layout of an array of DNA or other polymers with certain beneficial characteristics. According to another aspect of the invention, a computer system uses chip design files (104) to design and/or generate lithographic masks (110).

  5. Operator Station Design System - A computer aided design approach to work station layout

    NASA Technical Reports Server (NTRS)

    Lewis, J. L.

    1979-01-01

    The Operator Station Design System is resident in NASA's Johnson Space Center Spacecraft Design Division Performance Laboratory. It includes stand-alone minicomputer hardware and Panel Layout Automated Interactive Design and Crew Station Assessment of Reach software. The data base consists of the Shuttle Transportation System Orbiter Crew Compartment (in part), the Orbiter payload bay and remote manipulator (in part), and various anthropometric populations. The system is utilized to provide panel layouts, assess reach and vision, determine interference and fit problems early in the design phase, study design applications as a function of anthropometric and mission requirements, and to accomplish conceptual design to support advanced study efforts.

  6. Mechanical Design Technology--Modified. (Computer Assisted Drafting, Computer Aided Design). Curriculum Grant 84/85.

    ERIC Educational Resources Information Center

    Schoolcraft Coll., Livonia, MI.

    This document is a curriculum guide for a program in mechanical design technology (computer-assisted drafting and design developed at Schoolcraft College, Livonia, Michigan). The program helps students to acquire the skills of drafters and to interact with electronic equipment, with the option of becoming efficient in the computer-aided…

  7. Development of the engineering design integration (EDIN) system: A computer aided design development

    NASA Technical Reports Server (NTRS)

    Glatt, C. R.; Hirsch, G. N.

    1977-01-01

    The EDIN (Engineering Design Integration) System which provides a collection of hardware and software, enabling the engineer to perform man-in-the-loop interactive evaluation of aerospace vehicle concepts, was considered. Study efforts were concentrated in the following areas: (1) integration of hardware with the Univac Exec 8 System; (2) development of interactive software for the EDIN System; (3) upgrading of the EDIN technology module library to an interactive status; (4) verification of the soundness of the developing EDIN System; (5) support of NASA in design analysis studies using the EDIN System; (6) provide training and documentation in the use of the EDIN System; and (7) provide an implementation plan for the next phase of development and recommendations for meeting long range objectives.

  8. Laser bar code applied in computer aided design of power fittings

    NASA Astrophysics Data System (ADS)

    Yang, Xiaohong; Yang, Fan

    2010-10-01

    A computer aided process planning system is developed based on laser bar code technology to automatize and standardize processing-paper making. The system sorts fittings by analyzing their types, structures, dimensions, materials, and technics characteristics, groups and encodes the fittings with similar technology characteristics base on the theory of Group Technology (GT). The system produces standard technology procedures using integrative-parts method and stores them into technics databases. To work out the technology procedure of fittings, the only thing for users need to do is to scan the bar code of fittings with a laser code reader. The system can produce process-paper using decision trees method and then print the process-cards automatically. The software has already been applied in some power stations and is praised by the users.

  9. New Structural-Dynamics Module for Offshore Multimember Substructures within the Wind Turbine Computer-Aided Engineering Tool FAST: Preprint

    SciTech Connect

    Song, H.; Damiani, R.; Robertson, A.; Jonkman, J.

    2013-08-01

    FAST, developed by the National Renewable Energy Laboratory (NREL), is a computer-aided engineering (CAE) tool for aero-hydro-servo-elastic analysis of land-based and offshore wind turbines. This paper discusses recent upgrades made to FAST to enable loads simulations of offshore wind turbines with fixed-bottom, multimember support structures (e.g., jackets and tripods, which are commonly used in transitional-depth waters). The main theory and strategies for the implementation of the multimember substructure dynamics module (SubDyn) within the new FAST modularization framework are introduced. SubDyn relies on two main engineering schematizations: 1) a linear frame finite-element beam (LFEB) model and 2) a dynamics system reduction via Craig-Bampton's method. A jacket support structure and an offshore system consisting of a turbine atop a jacket substructure were simulated to test the SubDyn module and to preliminarily assess results against results from a commercial finite-element code.

  10. Modification to the Monte Carlo N-Particle (MCNP) Visual Editor (MCNPVised) to Read in Computer Aided Design (CAD) Files

    SciTech Connect

    Randolph Schwarz; Leland L. Carter; Alysia Schwarz

    2005-08-23

    Monte Carlo N-Particle Transport Code (MCNP) is the code of choice for doing complex neutron/photon/electron transport calculations for the nuclear industry and research institutions. The Visual Editor for Monte Carlo N-Particle is internationally recognized as the best code for visually creating and graphically displaying input files for MCNP. The work performed in this grant was used to enhance the capabilities of the MCNP Visual Editor to allow it to read in both 2D and 3D Computer Aided Design (CAD) files, allowing the user to electronically generate a valid MCNP input geometry.