Science.gov

Sample records for aided design computer

  1. Computer aided flexible envelope designs

    NASA Technical Reports Server (NTRS)

    Resch, R. D.

    1975-01-01

    Computer aided design methods are presented for the design and construction of strong, lightweight structures which require complex and precise geometric definition. The first, flexible structures, is a unique system of modeling folded plate structures and space frames. It is possible to continuously vary the geometry of a space frame to produce large, clear spans with curvature. The second method deals with developable surfaces, where both folding and bending are explored with the observed constraint of available building materials, and what minimal distortion result in maximum design capability. Alternative inexpensive fabrication techniques are being developed to achieve computer defined enclosures which are extremely lightweight and mathematically highly precise.

  2. 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.

  3. Computer-aided antibody design

    PubMed Central

    Kuroda, Daisuke; Shirai, Hiroki; Jacobson, Matthew P.; Nakamura, Haruki

    2012-01-01

    Recent clinical trials using antibodies with low toxicity and high efficiency have raised expectations for the development of next-generation protein therapeutics. However, the process of obtaining therapeutic antibodies remains time consuming and empirical. This review summarizes recent progresses in the field of computer-aided antibody development mainly focusing on antibody modeling, which is divided essentially into two parts: (i) modeling the antigen-binding site, also called the complementarity determining regions (CDRs), and (ii) predicting the relative orientations of the variable heavy (VH) and light (VL) chains. Among the six CDR loops, the greatest challenge is predicting the conformation of CDR-H3, which is the most important in antigen recognition. Further computational methods could be used in drug development based on crystal structures or homology models, including antibody–antigen dockings and energy calculations with approximate potential functions. These methods should guide experimental studies to improve the affinities and physicochemical properties of antibodies. Finally, several successful examples of in silico structure-based antibody designs are reviewed. We also briefly review structure-based antigen or immunogen design, with application to rational vaccine development. PMID:22661385

  4. 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)

  5. 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.

  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. Computer Code Aids Design Of Wings

    NASA Technical Reports Server (NTRS)

    Carlson, Harry W.; Darden, Christine M.

    1993-01-01

    AERO2S computer code developed to aid design engineers in selection and evaluation of aerodynamically efficient wing/canard and wing/horizontal-tail configurations that includes simple hinged-flap systems. Code rapidly estimates longitudinal aerodynamic characteristics of conceptual airplane lifting-surface arrangements. Developed in FORTRAN V on CDC 6000 computer system, and ported to MS-DOS environment.

  8. 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.

  9. 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…

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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,…

  15. 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.

  16. 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

  17. 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).

  18. 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.

  19. 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.

  20. 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

  1. Computer-aided design of GPCR ligands.

    PubMed

    Gutiérrez-de-Terán, Hugo; Keränen, Henrik; Azuaje, Jhonny; Rodríguez, David; Åqvist, Johan; Sotelo, Eddy

    2015-01-01

    The recent availability of several GPCR crystal structures now contributes decisively to the perspective of structure-based ligand design. In this context, computational approaches are extremely helpful, particularly if properly integrated in drug design projects with cooperation between computational and medicinal chemistry teams. Here, we present the pipelines used in one such project, devoted to the design of novel potent and selective antagonists for the different adenosine receptors. The details of the computational strategies are described, and particular attention is given to explain how these procedures can effectively guide the synthesis of novel chemical entities.

  2. 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.

  3. 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.

  4. 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.

  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. Memory interface simulator: A computer design aid

    NASA Technical Reports Server (NTRS)

    Taylor, D. S.; Williams, T.; Weatherbee, J. E.

    1972-01-01

    Results are presented of a study conducted with a digital simulation model being used in the design of the Automatically Reconfigurable Modular Multiprocessor System (ARMMS), a candidate computer system for future manned and unmanned space missions. The model simulates the activity involved as instructions are fetched from random access memory for execution in one of the system central processing units. A series of model runs measured instruction execution time under various assumptions pertaining to the CPU's and the interface between the CPU's and RAM. Design tradeoffs are presented in the following areas: Bus widths, CPU microprogram read only memory cycle time, multiple instruction fetch, and instruction mix.

  7. 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.

  8. 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…

  9. Luminance in computer-aided lighting design

    SciTech Connect

    Ward, G.J.; Rubinstein, F.M.; Grynberg, A.

    1987-08-01

    Traditionally, the lighting engineering community has emphasized illuminance, the amount of light reaching a surface, as the primary design goal. The Illuminating Engineering Society (IES) provides tables of illuminances for different types of tasks which lighting engineers consult in designing lighting systems. Illuminance has proven to be a popular metric because it corresponds closely to the amount of energy needed to light a building as well as the initial cost of the lighting system. Perhaps more importantly, illuminance is easy to calculate, especially in simple unobstructed spaces with direct lighting. However,illuminance is not well correlated with visual performance, which is the real reason for installing a lighting system in the first place. Visual performance is a psychophysiological quantity that has been tied to physical quantities such as contrast, size and adaptation level by subject experiments. These physical quantities can be approximated from illuminance using a host of assumptions about the environment, or derived directly from the distribution of luminance. Luminance is the quantity of light traveling through a point in a certain direction, and it is this quantity that the eye actually sees''. However, the difficulty of calculating luminance for common tasks has made it an unpopular metric. Despite its importance to lighting design, luminance is rarely used because there is a lack of the necessary computational tools.In this paper, we will demonstrate a computer calculation of luminance that has significant advantages for lighting design. As well as providing an immediate evaluation of visual quality for task performance, less quantifiable factors such as aesthetics can be studied in synthetic images produced by the program.

  10. Luminance in computer-aided lighting design

    SciTech Connect

    Ward, G.J.; Rubinstein, F.M.; Grynberg, A.

    1987-08-01

    Traditionally, the lighting engineering community has emphasized illuminance, the amount of light reaching a surface, as the primary design goal. The Illuminating Engineering Society (IES) provides tables of illuminances for different types of tasks which lighting engineers consult in designing lighting systems. Illuminance has proven to be a popular metric because it corresponds closely to the amount of energy needed to light a building as well as the initial cost of the lighting system. Perhaps more importantly, illuminance is easy to calculate, especially in simple unobstructed spaces with direct lighting. However,illuminance is not well correlated with visual performance, which is the real reason for installing a lighting system in the first place. Visual performance is a psychophysiological quantity that has been tied to physical quantities such as contrast, size and adaptation level by subject experiments. These physical quantities can be approximated from illuminance using a host of assumptions about the environment, or derived directly from the distribution of luminance. Luminance is the quantity of light traveling through a point in a certain direction, and it is this quantity that the eye actually ``sees``. However, the difficulty of calculating luminance for common tasks has made it an unpopular metric. Despite its importance to lighting design, luminance is rarely used because there is a lack of the necessary computational tools.In this paper, we will demonstrate a computer calculation of luminance that has significant advantages for lighting design. As well as providing an immediate evaluation of visual quality for task performance, less quantifiable factors such as aesthetics can be studied in synthetic images produced by the program.

  11. Computer aided design of spur gear teeth

    NASA Technical Reports Server (NTRS)

    Huston, R. L.; Mavriplis, D.; Oswald, F. B.

    1989-01-01

    Procedures for computer-modeling of spur gear tooth fabrication are given. It is shown that the standard involute tooth form results from a cutter with an involute shape rolling onto a gear blank. Specifically, the envelope of an involute is an involute. Examples are given and applications are discussed.

  12. 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.

  13. Computer-Aided dispatching system design specification

    SciTech Connect

    Briggs, M.G.

    1996-05-03

    This document defines the performance requirements for a graphic display dispatching system to support Hanford Patrol emergency response. This system is defined as a Commercial-Off the-Shelf computer dispatching system providing both text and graphical display information while interfacing with the diverse reporting system within the Hanford Facility. This system also provided expansion capabilities to integrate Hanford Fire and the Occurrence Notification Center and provides back-up capabilities for the Plutonium Processing Facility.

  14. Computer-Aided dispatching system design specification

    SciTech Connect

    Briggs, M.G.

    1996-09-27

    This document defines the performance requirements for a graphic display dispatching system to support Hanford Patrol emergency response. This document outlines the negotiated requirements as agreed to by GTE Northwest during technical contract discussions. This system defines a commercial off-the-shelf computer dispatching system providing both test and graphic display information while interfacing with diverse alarm reporting system within the Hanford Site. This system provided expansion capability to integrate Hanford Fire and the Occurrence Notification Center. The system also provided back-up capability for the Plutonium Processing Facility (PFP).

  15. 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…

  16. 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.

  17. The management of endodontically treated teeth using a Computer-Aided Design and Computer-Assisted Manufacturing/Computer-Aided Design and Computer-Integrated Manufacturing system.

    PubMed

    Foerster, J G; von Gonten, A S; Robert, G H

    1999-01-01

    This article introduces a new approach for restoring endodontically treated posterior teeth. Significantly reduced natural tooth structure often remains not only because of previous restorative measures but also because of endodontic procedures. Cast restorations for these teeth are almost universally recommended. The exception to this is the rare instance in which only conservative endodontic access openings exist in teeth presenting with no former existing restorations. Typically, multiple clinical appointments are required to complete the final cast restoration. This article presents Computer-Aided Design and Computer-Assisted Manufacturing/Computer-Aided Design and Computer-Integrated Manufacturing applications for restorative dentistry that provide the necessary care in an expeditious manner.

  18. 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.

  19. Comments on the computer aided design of Stirling engines

    SciTech Connect

    Reader, G.T.; Taylor, D.R.

    1983-08-01

    For a number of years the research team at the Royal Naval Engineering College's Stirling Engine Research Facility (SERF) have been investigating the computer aided design of Stirling engines and these investigations have involved the study and review of existing analytical and computer techniques and the development of 'in-house' methods. In this paper these experiences are summarized against the background of the state-of-the-art in the field as represented by the existing literature. An attempt is made to delineate the various design and analytical methods available and to show that they all have their place in a fully integrated design package.

  20. Microwave processing of a dental ceramic used in computer-aided design/computer-aided manufacturing.

    PubMed

    Pendola, Martin; Saha, Subrata

    2015-01-01

    Because of their favorable mechanical properties and natural esthetics, ceramics are widely used in restorative dentistry. The conventional ceramic sintering process required for their use is usually slow, however, and the equipment has an elevated energy consumption. Sintering processes that use microwaves have several advantages compared to regular sintering: shorter processing times, lower energy consumption, and the capacity for volumetric heating. The objective of this study was to test the mechanical properties of a dental ceramic used in computer-aided design/computer-aided manufacturing (CAD/CAM) after the specimens were processed with microwave hybrid sintering. Density, hardness, and bending strength were measured. When ceramic specimens were sintered with microwaves, the processing times were reduced and protocols were simplified. Hardness was improved almost 20% compared to regular sintering, and flexural strength measurements suggested that specimens were approximately 50% stronger than specimens sintered in a conventional system. Microwave hybrid sintering may preserve or improve the mechanical properties of dental ceramics designed for CAD/CAM processing systems, reducing processing and waiting times.

  1. 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.

  2. 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

  3. 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)…

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. Three-Dimensional Computer Aided Design of a Vertical Winnower

    NASA Astrophysics Data System (ADS)

    Bao, Yumei; Lin, Saijia; Weng, Lijie

    The research states home and abroad of the winnowing technology and winnowers are reviewed in brief. For the air duct, the core component of the winnower, the relevant technical parameters in the winnowing process are calculated based on the winnowing principle. The three-dimensional computer aided design (3D-CAD) software Solidworks is applied. The designed vertical winnower is able to separate different raw materials by adjusting the air speed and has been put into practical production to separate the Chinese traditional medicine with high separating effect.

  16. 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.

  17. CATIA - A computer aided design and manufacturing tridimensional system

    NASA Astrophysics Data System (ADS)

    Bernard, F.

    A properietary computer graphics-aided, three-dimensional interactive application (CATIA) design system is described. CATIA employs approximately 100 graphics displays, which are used by some 500 persons engaged in the definition of aircraft structures, structural strength analyses, the kinematic analysis of mobile elements, aerodynamic calculations, the choice of tooling in the machining of aircraft elements, and the programming of robotics. CATIA covers these diverse fields with a single data base. After a description of salient aspects of the system's hardware and software, graphics examples are given of the definition of curves, surfaces, complex volumes, and analytical tasks.

  18. 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.

  19. 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.

  20. 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.

  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. A critically appraised topic review of computer-aided design/computer-aided machining of removable partial denture frameworks.

    PubMed

    Lang, Lisa A; Tulunoglu, Ibrahim

    2014-01-01

    A critically appraised topic (CAT) review is presented about the use of computer-aided design (CAD)/computer-aided machining (CAM) removable partial denture (RPD) frameworks. A systematic search of the literature supporting CAD/CAM RPD systems revealed no randomized clinical trials, hence the CAT review was performed. A PubMed search yielded 9 articles meeting the inclusion criteria. Each article was characterized by study design and level of evidence. No clinical outcomes research has been published on the use of CAD/CAM RPDs. Low levels of evidence were found in the available literature. Clinical research studies are needed to determine the efficacy of this treatment modality.

  3. 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

  4. 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

  5. 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.

  6. 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.

  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. 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.

  9. 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.

  10. Computer aided design of microcircuits. Citations from the NTIS data base

    NASA Astrophysics Data System (ADS)

    Reed, W. E.

    1980-09-01

    Government sponsored research covering the computer aided design, modeling, layout, and packaging of integrated and other microelectronic circuits are cited. Computer programs and the use of computer graphics are included.

  11. 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…

  12. Computer-Aided Design and Computer-Aided Manufacturing Hydroxyapatite/Epoxide Acrylate Maleic Compound Construction for Craniomaxillofacial Bone Defects.

    PubMed

    Zhang, Lei; Shen, Shunyao; Yu, Hongbo; Shen, Steve Guofang; Wang, Xudong

    2015-07-01

    The aim of this study was to investigate the use of computer-aided design and computer-aided manufacturing hydroxyapatite (HA)/epoxide acrylate maleic (EAM) compound construction artificial implants for craniomaxillofacial bone defects. Computed tomography, computer-aided design/computer-aided manufacturing and three-dimensional reconstruction, as well as rapid prototyping were performed in 12 patients between 2008 and 2013. The customized HA/EAM compound artificial implants were manufactured through selective laser sintering using a rapid prototyping machine into the exact geometric shapes of the defect. The HA/EAM compound artificial implants were then implanted during surgical reconstruction. Color-coded superimpositions demonstrated the discrepancy between the virtual plan and achieved results using Geomagic Studio. As a result, the HA/EAM compound artificial bone implants were perfectly matched with the facial areas that needed reconstruction. The postoperative aesthetic and functional results were satisfactory. The color-coded superimpositions demonstrated good consistency between the virtual plan and achieved results. The three-dimensional maximum deviation is 2.12 ± 0.65  mm and the three-dimensional mean deviation is 0.27 ± 0.07  mm. No facial nerve weakness or pain was observed at the follow-up examinations. Only 1 implant had to be removed 2 months after the surgery owing to severe local infection. No other complication was noted during the follow-up period. In conclusion, computer-aided, individually fabricated HA/EAM compound construction artificial implant was a good craniomaxillofacial surgical technique that yielded improved aesthetic results and functional recovery after reconstruction.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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

  19. Dual-scan technique for the customization of zirconia computer-aided design/computer-aided manufacturing frameworks

    PubMed Central

    Andreiuolo, Rafael Ferrone; Sabrosa, Carlos Eduardo; Dias, Katia Regina H. Cervantes

    2013-01-01

    The use of bi-layered all-ceramic crowns has continuously grown since the introduction of computer-aided design/computer-aided manufacturing (CAD/CAM) zirconia cores. Unfortunately, despite the outstanding mechanical properties of zirconia, problems related to porcelain cracking or chipping remain. One of the reasons for this is that ceramic copings are usually milled to uniform thicknesses of 0.3-0.6 mm around the whole tooth preparation. This may not provide uniform thickness or appropriate support for the veneering porcelain. To prevent these problems, the dual-scan technique demonstrates an alternative that allows the restorative team to customize zirconia CAD/CAM frameworks with adequate porcelain thickness and support in a simple manner. PMID:24966718

  20. 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.

  1. 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.

  2. 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)

  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. 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…

  6. 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.

  7. Predictable Restorative Work Flow for Computer-Aided Design/Computer-Aided Manufacture-Fabricated Ceramic Veneers Utilizing a Virtual Smile Design Principle.

    PubMed

    Lin, W S; Zandinejad, A; Metz, M J; Harris, B T; Morton, D

    2015-01-01

    The purpose of this case report was to present the use of a contemporary digital photograph-assisted virtual smile design principle, an intraoral digital impression, and computer-aided design/computer-aided manufacture-fabricated lithium disilicate ceramic veneers to treat a patient with esthetic needs in the maxillary anterior region. By using the proposed digital restorative work flow, this case report demonstrated an effective communication pathway between the patient, clinician, and dental laboratory technician. Effective communication can help to achieve a more predictable and satisfactory esthetic outcome.

  8. 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.

  9. 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.

  10. 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

  11. 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.

  12. 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

  13. 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.

  14. Aiding Design of Wave Energy Converters via Computational Simulations

    NASA Astrophysics Data System (ADS)

    Jebeli Aqdam, Hejar; Ahmadi, Babak; Raessi, Mehdi; Tootkaboni, Mazdak

    2015-11-01

    With the increasing interest in renewable energy sources, wave energy converters will continue to gain attention as a viable alternative to current electricity production methods. It is therefore crucial to develop computational tools for the design and analysis of wave energy converters. A successful design requires balance between the design performance and cost. Here an analytical solution is used for the approximate analysis of interactions between a flap-type wave energy converter (WEC) and waves. The method is verified using other flow solvers and experimental test cases. Then the model is used in conjunction with a powerful heuristic optimization engine, Charged System Search (CSS) to explore the WEC design space. CSS is inspired by charged particles behavior. It searches the design space by considering candidate answers as charged particles and moving them based on the Coulomb's laws of electrostatics and Newton's laws of motion to find the global optimum. Finally the impacts of changes in different design parameters on the power takeout of the superior WEC designs are investigated. National Science Foundation, CBET-1236462.

  15. 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.

  16. 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.

  17. Computer aided production engineering

    SciTech Connect

    Not Available

    1986-01-01

    This book presents the following contents: CIM in avionics; computer analysis of product designs for robot assembly; a simulation decision mould for manpower forecast and its application; development of flexible manufacturing system; advances in microcomputer applications in CAD/CAM; an automated interface between CAD and process planning; CAM and computer vision; low friction pneumatic actuators for accurate robot control; robot assembly of printed circuit boards; information systems design for computer integrated manufacture; and a CAD engineering language to aid manufacture.

  18. 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.

  19. 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…

  20. 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.

  1. 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…

  2. A methodology and a tool for the computer aided design with constraints of electrical devices

    SciTech Connect

    Wurtz, F.; Bigeon, J.; Poirson, C.

    1996-05-01

    A methodology for the computer aided constrained design of electrical devices is presented and validated through the design of a slotless permanent structure. It is based on the use of the analytical design equations of the device. Symbolic calculation is widely used to generate an analysis program and a sensitivity computation program. Those programs are linked with an optimization algorithm that can take constraints into account. The methodology is tested with an experimental software named PASCOSMA.

  3. 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.

  4. Computer aided optimal design of space reflectors and radiation concentrators

    NASA Astrophysics Data System (ADS)

    Saprykin, Oleg A.; Spirochkin, Yuriy K.; Kinelev, Vladimir G.; Sulimov, Valeriy D.

    1998-06-01

    The goal of space radiation receiver design is achievement of its maximal reflecting properties under some technological and financial restrictions. Optimal design problems of this type are characterized by nonconvex nondifferentiable objective functions. A numerical technique for optimal design of the structures and an applied software REFLEX under development are proposed.

  5. Computer-aided industrial process design. The ASPEN project

    NASA Astrophysics Data System (ADS)

    1982-02-01

    The ASPEN Project was carried out at the Massachusetts Institute of Technology from 1976-1981. This report formally documents the work completed under the main contract between MIT and the US Department of Energy (Contract No. E(49-18)-2295 Task No. 9). In addition to the main contract, there were related contracts between MIT and the US Department of Energy on which work was reported separately. The project deliverables consisted of the source code and test problems for the ASPEN system on computer tape and a final report. The User Manual (1348 pages), the System Administrator Manual (1170 pages), and the Technical Reference Manual (1026 pages), and On-Line Documentation (Computer-Generated Tables) on magnetic tape were deliverables on a related, but separate contract. The source code versions of the system itself were provided, with installation instructions, for four different computers and operating system (IBM/OS, IBM/CMS, DEC/VAX, and Univac.

  6. 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...

  7. 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.

  8. 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

  9. 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.

  10. Computer-aided design of the human aortic root.

    PubMed

    Ovcharenko, E A; Klyshnikov, K U; Vlad, A R; Sizova, I N; Kokov, A N; Nushtaev, D V; Yuzhalin, A E; Zhuravleva, I U

    2014-11-01

    The development of computer-based 3D models of the aortic root is one of the most important problems in constructing the prostheses for transcatheter aortic valve implantation. In the current study, we analyzed data from 117 patients with and without aortic valve disease and computed tomography data from 20 patients without aortic valvular diseases in order to estimate the average values of the diameter of the aortic annulus and other aortic root parameters. Based on these data, we developed a 3D model of human aortic root with unique geometry. Furthermore, in this study we show that by applying different material properties to the aortic annulus zone in our model, we can significantly improve the quality of the results of finite element analysis. To summarize, here we present four 3D models of human aortic root with unique geometry based on computational analysis of ECHO and CT data. We suggest that our models can be utilized for the development of better prostheses for transcatheter aortic valve implantation.

  11. 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.

  12. Computer-aided design of aptamers for cytochrome p450.

    PubMed

    Shcherbinin, Dmitrii S; Gnedenko, Oksana V; Khmeleva, Svetlana A; Usanov, Sergey A; Gilep, Andrei A; Yantsevich, Aliaksei V; Shkel, Tatsiana V; Yushkevich, Ivan V; Radko, Sergey P; Ivanov, Alexis S; Veselovsky, Alexander V; Archakov, Alexander I

    2015-08-01

    Aptamers are short single-stranded DNA or RNA oligonucleotides that can bind to their targets with high affinity and specificity. Usually, they are experimentally selected using the SELEX method. Here, we describe an approach toward the in silico selection of aptamers for proteins. This approach involves three steps: finding a potential binding site, designing the recognition and structural parts of the aptamers and evaluating the experimental affinity. Using this approach, a set of 15-mer aptamers for cytochrome P450 51A1 was designed using docking and molecular dynamics simulation. An experimental evaluation of the synthesized aptamers using SPR biosensor showed that these aptamers interact with cytochrome P450 51A1 with Kd values in the range of 10(-6)-10(-7) M. PMID:26166326

  13. Variance Analysis and Comparison in Computer-Aided Design

    NASA Astrophysics Data System (ADS)

    Ullrich, T.; Schiffer, T.; Schinko, C.; Fellner, D. W.

    2011-09-01

    The need to analyze and visualize differences of very similar objects arises in many research areas: mesh compression, scan alignment, nominal/actual value comparison, quality management, and surface reconstruction to name a few. In computer graphics, for example, differences of surfaces are used for analyzing mesh processing algorithms such as mesh compression. They are also used to validate reconstruction and fitting results of laser scanned surfaces. As laser scanning has become very important for the acquisition and preservation of artifacts, scanned representations are used for documentation as well as analysis of ancient objects. Detailed mesh comparisons can reveal smallest changes and damages. These analysis and documentation tasks are needed not only in the context of cultural heritage but also in engineering and manufacturing. Differences of surfaces are analyzed to check the quality of productions. Our contribution to this problem is a workflow, which compares a reference / nominal surface with an actual, laser-scanned data set. The reference surface is a procedural model whose accuracy and systematics describe the semantic properties of an object; whereas the laser-scanned object is a real-world data set without any additional semantic information.

  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. 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.

  16. 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

  17. 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.

  18. Simulation tools for computer-aided design and numerical investigations of high-power gyrotrons

    NASA Astrophysics Data System (ADS)

    Damyanova, M.; Balabanova, E.; Kern, S.; Illy, S.; Sabchevski, S.; Thumm, M.; Vasileva, E.; Zhelyazkov, I.

    2012-03-01

    Modelling and simulation are essential tools for computer-aided design (CAD), analysis and optimization of high-power gyrotrons used as radiation sources for electron cyclotron resonance heating (ECRH) and current drive (ECCD) of magnetically confined plasmas in the thermonuclear reactor ITER. In this communication, we present the current status of our simulation tools and discuss their further development.

  19. 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…

  20. Computer program for design and performance analysis of navigation-aid power systems

    NASA Technical Reports Server (NTRS)

    Weiner, H.; Wiener, P.; Williams, K.

    1976-01-01

    The paper examines the requirements, design rationale, operation, and verification of a computer program designated as design synthesis/performance analysis (DSPA) computer program, which is capable of performing all the calculations necessary to understand the overall characteristics of solar array/battery power systems for navigation-aid applications. Despite the uncertainties in the erratic solar array degradation data and the potential impact on actual battery behavior, verification of the DSPA is considered successful. The program is shown to have the capability of simulating the performance of solar array/battery navigation-aid power systems. It can also be used to synthesize power system designs and provide essential design and cost data.

  1. 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

  2. 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.

  3. 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

  4. 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.

  5. 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.

  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. 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.

  8. [A computer-aided design assessment system for recovery life support technology options].

    PubMed

    Chen, J; Wang, F; Sun, J; Shang, C

    1997-04-01

    A specific computer-aided decision support system was designed and implemented for design computation and decision assessment of environmental control and life support system of manned space station. An advanced multiobjective decision methodology and a hierarchic structure model of assessment index of recovery life support system was developed. The program incorporates a database for each technology option, metabolic design loads associated with crew activity, mission model variables to accommodate evolving mission requirements, and algorithms to produce products criteria in order to provide recommendations relative to candidate technology selection and development. A specific structure was developed for the decision system which consists of a database, a methodology base and a model base as well as their management systems. Moreover, a centre control system with friendly user interface plays a very important role in the man-computer interaction.

  9. 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.

  10. Role of computer-aided drug design in modern drug discovery.

    PubMed

    Macalino, Stephani Joy Y; Gosu, Vijayakumar; Hong, Sunhye; Choi, Sun

    2015-09-01

    Drug discovery utilizes chemical biology and computational drug design approaches for the efficient identification and optimization of lead compounds. Chemical biology is mostly involved in the elucidation of the biological function of a target and the mechanism of action of a chemical modulator. On the other hand, computer-aided drug design makes use of the structural knowledge of either the target (structure-based) or known ligands with bioactivity (ligand-based) to facilitate the determination of promising candidate drugs. Various virtual screening techniques are now being used by both pharmaceutical companies and academic research groups to reduce the cost and time required for the discovery of a potent drug. Despite the rapid advances in these methods, continuous improvements are critical for future drug discovery tools. Advantages presented by structure-based and ligand-based drug design suggest that their complementary use, as well as their integration with experimental routines, has a powerful impact on rational drug design. In this article, we give an overview of the current computational drug design and their application in integrated rational drug development to aid in the progress of drug discovery research.

  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. 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. 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.

  14. 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.

  15. Computer-aided design and computer-aided manufacture (CAD/CAM) system for construction of spinal orthosis for patients with adolescent idiopathic scoliosis.

    PubMed

    Wong, M S

    2011-01-01

    ABSTRACT Spinal orthoses are commonly prescribed to patients with moderate adolescent idiopathic scoliosis (AIS) for prevention of further curve deterioration. In conventional manufacturing method, plaster bandages are used to obtain the patient's body contour and then the plaster cast is rectified manually. With computer-aided design and computer-aided manufacture (CAD/CAM) system, a series of automated processes from body scanning to digital rectification and milling of the positive model can be performed in a fast and accurate fashion. The purpose of this manuscript is to introduce the application of CAD/CAM system to the construction of spinal orthosis for patients with AIS. Based on evidence within the literature, CAD/CAM method can achieve similar clinical outcomes but with higher efficiency than the conventional fabrication method. Therefore, CAD/CAM method should be considered a substitute to the conventional method in fabrication of spinal orthoses for patients with AIS.

  16. Microcomputed tomography marginal fit evaluation of computer-aided design/computer-aided manufacturing crowns with different methods of virtual model acquisition.

    PubMed

    das Neves, Flavio Domingues; do Prado, Celio Jesus; Prudente, Marcel Santana; Carneiro, Thiago Almeida Prado Naves; Zancope, Karla; Davi, Leticia Resende; Mendonca, Gustavo; Cooper, Lyndon; Soares, Carlos Jose

    2015-01-01

    This in vitro study used microcomputed tomography to evaluate the marginal fit of crowns fabricated using a chairside computer-aided design/computer-aided manufacturing (CAD/CAM) system with different methods of virtual model acquisition. Crowns were fabricated to fit in a cast containing a single human premolar. Four methods of virtual model acquisition were used: Group 1 (control), digital impressioning of a typodont; Group 2, digital impressioning of a powdered typodont; Group 3, digital impressioning of a regular impression; and Group 4, digital impressioning of a master cast. Statistically significant differences were found between the marginal gap of Group 2 and the other groups (P < 0.05); no differences were found among Groups 1, 3, and 4. The results showed that crowns fabricated using the chairside CAD/CAM system exhibited significantly smaller vertical misfit when a thin layer of powder was applied over the typodont before digital impressioning.

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. An overlooked yet ubiquitous fluoride congenitor: binding bifluoride in triazolophanes using computer-aided design.

    PubMed

    Ramabhadran, Raghunath O; Liu, Yun; Hua, Yuran; Ciardi, Moira; Flood, Amar H; Raghavachari, Krishnan

    2014-04-01

    Despite its ubiquity during the binding and sensing of fluoride, the role of bifluoride (HF2(-)) and its binding properties are almost always overlooked. Here, we give one of the first examinations of bifluoride recognition in which we use computer-aided design to modify the cavity shape of triazolophanes to better match with HF2(-). Computational investigation indicates that HF2(-) and Cl(-) should have similar binding affinities to the parent triazolophane in the gas phase. Evaluation of the binding geometries revealed a preference for binding of the linear HF2(-) along the north-south axis with a smaller Boltzmann weighted population aligned east-west and all states being accessed rapidly through in-plane precessional rotations of the anion. While the (1)H NMR spectroscopy studies are consistent with the calculated structural aspects, binding affinities in solution were determined to be significantly smaller for the bifluoride than the chloride. Computed geometries suggested that a 20° tilting of the bifluoride (stemming from the cavity size) could account for the 25-fold difference between the two binding affinities, HF2(-) < Cl(-). Structural variations to the triazolophane's geometry and electronic modifications to the network of hydrogen bond donors were subsequently screened in a stepwise manner using density functional theory calculations to yield a final design that eliminates the tilting. Correspondingly, the bifluoride's binding affinity (K ∼ 10(6) M(-1)) increased and was also found to remain equal to chloride in the gas and solution phases. The new oblate cavity appeared to hold the HF2(-) in a single east-west arrangement. Our findings demonstrate the promising ability of computer-aided design to fine-tune the structural and electronic match in anion receptors as a means to control the arrangement and binding strength of a desired guest.

  7. An evaluation of computer aided design of below-knee prosthetic sockets.

    PubMed

    Topper, A K; Fernie, G R

    1990-12-01

    Forty-eight below-knee amputees compared sockets designed using CANFIT computer aided design (CAD) software with sockets designed using conventional methods. Each subject was fitted by one prosthetist who used conventional techniques and one who used the CANFIT system to design the socket. Prosthetists alternated design methods for each new subject. The prosthetist using the conventional techniques was allowed up to 2 design attempts and the prosthetist using the CANFIT system was allowed up to 5 design attempts. After 2 design attempts with each method 21% of the subjects preferred the CANFIT design socket. Following up to 5 attempts 54% preferred the CANFIT designed socket. A jury of experts made an assessment of the CANFIT system and of CAD in prosthetics. The jury did not think that the version of the system tested was cost effective but that at the rate that it was improving it would become such within 3 to 5 years. The jury noted that, as well as monetary benefits, CAD presents the possibility of benefits in other areas such as research and teaching. A number of specific suggestions regarding the use and development of CAD in prosthetics were also made.

  8. 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.

  9. History and evolution of the pharmacophore concept in computer-aided drug design.

    PubMed

    Güner, Osman F

    2002-12-01

    With computer-aided drug design established as an integral part of the lead discovery and optimization process, pharmacophores have become a focal point for conceptualizing and understanding receptor-ligand interactions. In the structure-based design process, pharmacophores can be used to align molecules based on the three-dimensional arrangement of chemical features or to develop predictive models (e.g., 3D-QSAR) that correlate with the experimental activities of a given training set. Pharmacophores can be also used as search queries for retrieving potential leads from structural databases, for designing molecules with specific desired attributes, or as fingerprints for assessing similarity and diversity of molecules. This review article presents a historical perspective on the evolution and use of the pharmacophore concept in the pharmaceutical, biotechnology, and fragrances industry with published examples of how the technology has contributed and advanced the field. PMID:12470283

  10. 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.

  11. 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.

  12. Computer aided process planning and die design in simulation environment in sheet metal forming

    NASA Astrophysics Data System (ADS)

    Tisza, Miklós; Lukács, Zsolt

    2013-12-01

    During the recent 10-15 years, Computer Aided Process Planning and Die Design evolved as one of the most important engineering tools in sheet metal forming, particularly in the automotive industry. This emerging role is strongly emphasized by the rapid development of Finite Element Modeling, as well. The purpose of this paper is to give a general overview about the recent achievements in this very important field of sheet metal forming and to introduce some special results in this development activity. Therefore, in this paper, an integrated process simulation and die design system developed at the University of Miskolc, Department of Mechanical Engineering will be analyzed. The proposed integrated solutions have great practical importance to improve the global competitiveness of sheet metal forming in the very important segment of industry. The concept described in this paper may have specific value both for process planning and die design engineers.

  13. 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.

  14. 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

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

    PubMed

    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.

  16. 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

  17. 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%.

  18. 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.

  19. 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

  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.

  1. 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.

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

    DOE PAGES

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

    2016-02-17

    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 themore » performance of known bis-phosphine oxide extractants. For the case where 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.« less

  3. 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.

  4. 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.

  5. 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.

  6. Interface load analysis for computer-aided design of below-knee prosthetic sockets.

    PubMed

    Reynolds, D P; Lord, M

    1992-07-01

    A finite-element analysis is made for the compression of soft tissues of the residual lower limb contained in a prosthetic socket. The analysis is relevant to static loading during stance in a patellar-tendon-bearing, below-knee design of socket. Values of Young's modulus are obtained experimentally for use in the model. One of the main objectives is to study the sensitivity of the loading to these values and also to other assumed conditions. Using direct pressure at the limb/socket interface and vertical stiffness as indicators, changes in material properties, socket alignment and socket rectification are investigated; assumptions about the frictional characteristic at the interface are seen to be critical in determination of load distribution. This type of analysis may provide the next stage of refinement for computer-aided socket design systems.

  7. Experiences in control system design aided by interactive computer programs: temperature control of the laser isotope separation vessel

    SciTech Connect

    Gavel, D.T.; Pittenger, L.C.; McDonald, J.S.; Cramer, P.G.; Herget, C.J.

    1985-01-01

    A robust control system has been designed to regulate temperature in a vacuum vessel. The thermodynamic process is modeled by a set of nonlinear, implicit differential equations. The control design and analysis task exercised many of the computer-aided control systems design software packages, including MATLAB, DELIGHT, and LSAP. The working environment is a VAX computer. Advantages and limitations of the software and environment, and the impact on final controller design is discussed.

  8. PUZZLE - A program for computer-aided design of printed circuit artwork

    NASA Technical Reports Server (NTRS)

    Harrell, D. A. W.; Zane, R.

    1971-01-01

    Program assists in solving spacing problems encountered in printed circuit /PC/ design. It is intended to have maximum use for two-sided PC boards carrying integrated circuits, and also aids design of discrete component circuits.

  9. 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.

  10. 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.

  11. 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.

  12. Computer-Aided Geometry Modeling

    NASA Technical Reports Server (NTRS)

    Shoosmith, J. N. (Compiler); Fulton, R. E. (Compiler)

    1984-01-01

    Techniques in computer-aided geometry modeling and their application are addressed. Mathematical modeling, solid geometry models, management of geometric data, development of geometry standards, and interactive and graphic procedures are discussed. The applications include aeronautical and aerospace structures design, fluid flow modeling, and gas turbine design.

  13. [Computer aided design and manufacture of the porcelain fused to metal crown].

    PubMed

    Nie, Xin; Cheng, Xiaosheng; Dai, Ning; Yu, Qing; Hao, Guodong; Sun, Quanping

    2009-04-01

    In order to satisfy the current demand for fast and high-quality prosthodontics, we have carried out a research in the fabrication process of the porcelain fused to metal crown on molar with CAD/CAM technology. Firstly, we get the data of the surface mesh on preparation teeth through a 3D-optical grating measuring system. Then, we reconstruct the 3D-model crown with the computer-aided design software which was developed by ourselves. Finally, with the 3D-model data, we produce a metallic crown on a high-speed CNC carving machine. The result has proved that the metallic crown can match the preparation teeth ideally. The fabrication process is reliable and efficient, and the restoration is precise and steady in quality. PMID:19499776

  14. 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.

  15. 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.

  16. 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.

  17. Prospective on multiscale simulation of virus-like particles: Application to computer-aided vaccine design.

    PubMed

    Abi Mansour, Andrew; Sereda, Yuriy V; Yang, Jing; Ortoleva, Peter J

    2015-11-01

    Simulations of virus-like particles needed for computer-aided vaccine design highlight the need for new algorithms that accelerate molecular dynamics. Such simulations via conventional molecular dynamics present a practical challenge due to the millions of atoms involved and the long timescales of the phenomena of interest. These phenomena include structural transitions, self-assembly, and interaction with a cell surface. A promising approach for addressing this challenge is multiscale factorization. The approach is distinct from coarse-graining techniques in that it (1) avoids the need for conjecturing phenomenological governing equations for coarse-grained variables, (2) provides simulations with atomic resolution, (3) captures the cross-talk between disturbances at the atomic and the whole virus-like particle scale, and (4) achieves significant speedup over molecular dynamics. A brief review of multiscale factorization method is provided, as is a prospective on its development.

  18. Molecular structure descriptors in the computer-aided design of biologically active compounds

    NASA Astrophysics Data System (ADS)

    Raevsky, Oleg A.

    1999-06-01

    The current state of description of molecular structure in computer-aided molecular design of biologically active compounds by means of descriptors is analysed. The information contents of descriptors increases in the following sequence: element-level descriptors-structural formulae descriptors-electronic structure descriptors-molecular shape descriptors-intermolecular interaction descriptors. Each subsequent class of descriptors normally covers information contained in the previous-level ones. It is emphasised that it is practically impossible to describe all the features of a molecular structure in terms of any single class of descriptors. It is recommended to optimise the number of descriptors used by means of appropriate statistical procedures and characteristics of structure-property models based on these descriptors. The bibliography includes 371 references.

  19. Computer aided design of prosthetic sockets for below-knee amputees.

    PubMed

    Saunders, C G; Foort, J; Bannon, M; Lean, D; Panych, L

    1985-04-01

    A computer-aided sculpting system for use in prosthetics is described. The prosthetist's sculpting tools now consist of a computer, a graphics terminal, a mouse and an on-screen moveable cursor. Accompanied by the system software, these tools allow systematic modification of a primitive socket using techniques analogous to those used by a prosthetist working with rasps and plaster.

  20. Marginal accuracy of four-unit zirconia fixed dental prostheses fabricated using different computer-aided design/computer-aided manufacturing systems.

    PubMed

    Kohorst, Philipp; Brinkmann, Henrike; Li, Jiang; Borchers, Lothar; Stiesch, Meike

    2009-06-01

    Besides load-bearing capacity, marginal accuracy is a further crucial factor influencing the clinical long-term reliability of fixed dental prostheses (FDPs). The aim of this in vitro study was to evaluate the marginal fit of four-unit zirconia bridge frameworks fabricated using four different computer-aided design (CAD)/computer-aided manufacturing (CAM) systems. Ten frameworks were manufactured using each fabricating system. Three systems (inLab, Everest, Cercon) processed white-stage zirconia blanks, which had to be sintered to final density after milling, while with one system (Digident) restorations were directly milled from a fully sintered material. After manufacturing, horizontal and vertical marginal discrepancies, as well as the absolute marginal discrepancy, were determined by means of a replica technique. The absolute marginal discrepancy, which is considered to be the most suitable parameter reflecting restorations' misfit in the marginal area, had a mean value of 58 mum for the Digident system. By contrast, mean absolute marginal discrepancies for the three other systems, processing presintered blanks, differed significantly and ranged between 183 and 206 mum. Within the limitations of this study, it could be concluded that the marginal fit of zirconia FDPs is significantly dependent on the CAD/CAM system used, with restorations processed of fully sintered zirconia showing better fitting accuracy. PMID:19583762

  1. 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.

  2. 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.

  3. Recent advances in computer-aided drug design as applied to anti-influenza drug discovery.

    PubMed

    Mallipeddi, Prema L; Kumar, Gyanendra; White, Stephen W; Webb, Thomas R

    2014-01-01

    Influenza is a seasonal and serious health threat, and the recent outbreak of H7N9 following the pandemic spread of H1N1 in 2009 has served to emphasize the importance of anti-influenza drug discovery. Zanamivir (Relenza™) and oseltamivir (Tamiflu(®)) are two antiviral drugs currently recommended by the CDC for treating influenza. Both are examples of the successful application of structure-based drug design strategies. These strategies have combined computer- based approaches, such as docking- and pharmacophore-based virtual screening with X-ray crystallographic structural analyses. Docking is a routinely used computational method to identify potential hits from large compound libraries. This method has evolved from simple rigid docking approaches to flexible docking methods to handle receptor flexibility and to enhance hit rates in virtual screening. Virtual screening approaches can employ both ligand-based and structurebased pharmacophore models depending on the available information. The exponential growth in computing power has increasingly facilitated the application of computer-aided methods in drug discovery, and they now play significant roles in the search for novel therapeutics. An overview of these computational tools is presented in this review, and recent advances and challenges will be discussed. The focus of the review will be anti-influenza drug discovery and how advances in our understanding of viral biology have led to the discovery of novel influenza protein targets. Also discussed will be strategies to circumvent the problem of resistance emerging from rapid mutations that has seriously compromised the efficacy of current anti-influenza therapies.

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

    PubMed

    Douguet, Dominique

    2010-07-01

    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.

  6. 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

  7. 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.

  8. Computer-aided rational design of the phosphotransferase system for enhanced glucose uptake in Escherichia coli.

    PubMed

    Nishio, Yousuke; Usuda, Yoshihiro; Matsui, Kazuhiko; Kurata, Hiroyuki

    2008-01-01

    The phosphotransferase system (PTS) is the sugar transportation machinery that is widely distributed in prokaryotes and is critical for enhanced production of useful metabolites. To increase the glucose uptake rate, we propose a rational strategy for designing the molecular architecture of the Escherichia coli glucose PTS by using a computer-aided design (CAD) system and verified the simulated results with biological experiments. CAD supports construction of a biochemical map, mathematical modeling, simulation, and system analysis. Assuming that the PTS aims at controlling the glucose uptake rate, the PTS was decomposed into hierarchical modules, functional and flux modules, and the effect of changes in gene expression on the glucose uptake rate was simulated to make a rational strategy of how the gene regulatory network is engineered. Such design and analysis predicted that the mlc knockout mutant with ptsI gene overexpression would greatly increase the specific glucose uptake rate. By using biological experiments, we validated the prediction and the presented strategy, thereby enhancing the specific glucose uptake rate.

  9. 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.

  10. Computer Instructional Aids for Undergraduate Control Education.

    ERIC Educational Resources Information Center

    Volz, Richard A.; And Others

    Engineering is coming to rely more and more heavily upon the computer for computations, analyses, and graphic displays which aid the design process. A general purpose simulation system, the Time-shared Automatic Control Laboratory (TACL), and a set of computer-aided design programs, Control Oriented Interactive Graphic Analysis and Design…

  11. Evaluation of three-dimensional position change of the condylar head after orthognathic surgery using computer-aided design/computer-aided manufacturing-made condyle positioning jig.

    PubMed

    Kim, Hyung-Mo; Baek, Seung-Hak; Kim, Tae-Yun; Choi, Jin-Young

    2014-11-01

    This study was performed to evaluate the efficacy of computer-aided design/computer-aided manufacturing (CAM/CAD)-made condyle positioning jig in orthognathic surgery. The sample consisted of 40 mandibular condyles of 20 patients with class III malocclusion who underwent bilateral sagittal split ramus osteotomy with semirigid fixation (6 men and 14 women; mean age, 25 y; mean amount of mandibular setback, 5.8 mm). Exclusion criteria were patients who needed surgical correction of the frontal ramal inclination and had signs and symptoms of the temporomandibular disorder before surgery. Three-dimensional computed tomograms were taken 1 month before the surgery (T1) and 1 day after the surgery (T2). The condylar position was evaluated at the T1 and T2 stages on the axial, frontal, and sagittal aspects in the three-dimensional coordinates. The linear change of the posterior border of the proximal segment of the ramus between T1 and T2 was also evaluated in 30 condyles (15 patients), with the exception of 10 condyles of 5 patients who received mandibular angle reduction surgery. There was no significant difference in the condylar position in the frontal and sagittal aspects (P > 0.05). Although there was a significant difference in the condylar position in the axial aspect (P < 0.01), the amount of difference was less than 1 mm and 1 degree; it can be considered clinically nonsignificant. In the linear change of the posterior border of the proximal segment of the ramus, the mean change was 1.4 mm and 60% of the samples showed a minimal change of less than 1 mm. The results of this study suggest that CAD/CAM-made condyle positioning jig is easy to install and reliable to use in orthognathic surgery.

  12. 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.

  13. 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.

  14. 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.

  15. Computer-Aided Design of Liquid Crystals: A Mean Field Approach

    NASA Astrophysics Data System (ADS)

    Weider, Titus; Glaser, Matthew A.; Clark, Noel A.

    1997-08-01

    The directed design of soft materials is challenging owing to their complex structure and interactions. A promising strategy for the modeling of organic materials involves the replacement of the explicit condensed phase environment of a molecule or group of molecules by an effective mean field potential. We have created mean field theory-based methods for the routine pre-synthesis prediction of materials properties of liquid crystals, including phase behavior, linear and nonlinear optical properties, and spontaneous polarization density. These methods are semi-empirical in the sense that they rely on experimental data (e.g. from NMR or FTIR measurements) for the development of transferable mean field potentials capable of yielding quantitative predictions for novel materials. Our calculations involve detailed quantum chemical studies of conformational energy surfaces and evaluation of statistical averages by exact enumeration (within an RIS approximation) or importance sampling (for fully flexible molecular models). This strategy appears to have great promise, and represents perhaps the only viable approach to computer-aided design of liquid crystalline materials.

  16. 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

  17. Shape sensing for computer aided below-knee prosthetic socket design.

    PubMed

    Fernie, G R; Griggs, G; Bartlett, S; Lunau, K

    1985-04-01

    Shape sensing is useful in the computer aided prosthetic fitting process for two purposes. 1. To input characteristic prosthetic shapes that have been developed over the years through the experience of prosthetists. 2. To provide an accurate and rapid measurement of the anatomical shape of the stump. This paper describes two instruments which have been built to meet these objectives.

  18. 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

  19. 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.

  20. 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

  1. 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

  2. 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…

  3. 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…

  4. Computer aided surface representation

    SciTech Connect

    Barnhill, R.E.

    1989-02-09

    The central research problem of this project is the effective representation and display of surfaces, interpolating to given information, in three or more dimensions. In a typical problem, we wish to create a surface from some discrete information. If this information is itself on another surface, the problem is to determine a surface defined on a surface,'' which is discussed below. Often, properties of an already constructed surface are desired: such geometry processing'' is described below. The Summary of Proposed Research from our original proposal describes the aims of this research project. This Summary and the Table of Contents from the original proposal are enclosed as an Appendix to this Progress Report. The broad sweep from constructive mathematics through algorithms and computer graphics displays is utilized in the research. The wide range of activity, directed in both theory and applications, makes this project unique. Last month in the first Ardent Titan delivered in the State of Arizona came to our group, funded by the DOE and Arizona State University. Although the Titan is a commercial product, its newness requires our close collaboration with Ardent to maximize results. During the past year, four faculty members and several graduate research assistants have worked on this DOE project. The gaining of new professionals is an important aspect of this project. A listing of the students and their topics is given in the Appendix. The most significant publication during the past year is the book, Curves and Surfaces for Computer Aided Geometric Design, by Dr. Gerald Farin. This 300 page volume helps fill a considerable gap in the subject and includes many new results on Bernstein-Bezier curves and surfaces.

  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. 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.

  7. 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.

  8. 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

  9. Validation of RetroPath, a computer-aided design tool for metabolic pathway engineering.

    PubMed

    Fehér, Tamás; Planson, Anne-Gaëlle; Carbonell, Pablo; Fernández-Castané, Alfred; Grigoras, Ioana; Dariy, Ekaterina; Perret, Alain; Faulon, Jean-Loup

    2014-11-01

    Metabolic engineering has succeeded in biosynthesis of numerous commodity or high value compounds. However, the choice of pathways and enzymes used for production was many times made ad hoc, or required expert knowledge of the specific biochemical reactions. In order to rationalize the process of engineering producer strains, we developed the computer-aided design (CAD) tool RetroPath that explores and enumerates metabolic pathways connecting the endogenous metabolites of a chassis cell to the target compound. To experimentally validate our tool, we constructed 12 top-ranked enzyme combinations producing the flavonoid pinocembrin, four of which displayed significant yields. Namely, our tool queried the enzymes found in metabolic databases based on their annotated and predicted activities. Next, it ranked pathways based on the predicted efficiency of the available enzymes, the toxicity of the intermediate metabolites and the calculated maximum product flux. To implement the top-ranking pathway, our procedure narrowed down a list of nine million possible enzyme combinations to 12, a number easily assembled and tested. One round of metabolic network optimization based on RetroPath output further increased pinocembrin titers 17-fold. In total, 12 out of the 13 enzymes tested in this work displayed a relative performance that was in accordance with its predicted score. These results validate the ranking function of our CAD tool, and open the way to its utilization in the biosynthesis of novel compounds.

  10. 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.

  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. 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).

  13. 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).

  14. 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.

  15. 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.

  16. 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.

  17. Computer-aided design and manufacture of an above-knee amputee socket.

    PubMed

    Torres-Moreno, R; Saunders, C G; Foort, J; Morrison, J B

    1991-01-01

    This paper describes the initial test results obtained from a newly developed computer-aided socket design (CASD) and manufacturing (CASM) process for above-knee amputees. Anthropometric measures taken from an amputee provided input information to a CASD system. Using these measurements, data from a reference shape library stored in the computer were selected and modified to create a unique socket shape reflecting the particular characteristics of the amputation stump. The resultant shape was produced as a 'primitive' test socket by a CASM process. Numerical shape data were then transferred to a CNC milling machine to construct a negative cast, from which the primitive socket was produced by a vacuum-forming procedure. The resultant primitive socket shape was fitted and the amputee was able to load the socket without discomfort. Some shape discrepancies were identified and the shape data were modified interactively by the CASD system to create a final socket shape. The final socket shape was manufactured and worn by the amputee during a 35 min walking trial. Subjective evaluation was that the socket provided comfort and control comparable with that of the conventional socket, and proved to be acceptable to the amputee. This was followed by a 2-month home trial which was also successful. The CASD socket shapes were compared numerically in area, shape and volume with data taken from the original socket worn by the amputee, a new socket made by conventional methods and a topographic model of the amputation stump. The final CASD socket shape compared favourably with that of a socket manufactured by conventional methods.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2002669

  18. 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

  19. 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.

  20. Designing State Aid Formulas

    ERIC Educational Resources Information Center

    Zhao, Bo; Bradbury, Katharine

    2009-01-01

    This paper designs a new equalization-aid formula based on fiscal gaps of local communities. When states are in transition to a new local aid formula, the issue of whether and how to hold existing aid harmless poses a challenge. The authors show that some previous studies and the formulas derived from them give differential weights to existing and…

  1. 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

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. AESOP: A computer-aided design program for linear multivariable control systems

    NASA Technical Reports Server (NTRS)

    Lehtinen, B.; Geyser, L. C.

    1982-01-01

    An interactive computer program (AESOP) which solves quadratic optimal control and is discussed. The program can also be used to perform system analysis calculations such as transient and frequency responses, controllability, observability, etc., in support of the control and filter design computations.

  10. A dc model for power switching transistors suitable for computer-aided design and analysis

    NASA Technical Reports Server (NTRS)

    Wilson, P. M.; George, R. T., Jr.; Owen, H. A.; Wilson, T. G.

    1979-01-01

    A model for bipolar junction power switching transistors whose parameters can be readily obtained by the circuit design engineer, and which can be conveniently incorporated into standard computer-based circuit analysis programs is presented. This formulation results from measurements which may be made with standard laboratory equipment. Measurement procedures, as well as a comparison between actual and computed results, are presented.

  11. [A study of the computer aid design for tooth arrangement of full denture].

    PubMed

    Lu, P J

    1992-05-01

    This paper is to use the power function Simpson's integration formula and some other methods to describe the geometric form of the dentition and edentulous arch in accordance with the theories and principles of tooth arrangement in textbook. The matching equations of artificial dentition and edentulous arch form and size are developed by using the multivariable regression method to analyze and summarize the clinical experiences of prosthodontists. Based on the above facts, a computer program that can be used to aid the dentist to arrange the artificial teeth for full denture is developed with Quick Basic Language and realized them in PC miniprocessors. PMID:1292895

  12. 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

  13. User-Centered Computer Aided Language Learning

    ERIC Educational Resources Information Center

    Zaphiris, Panayiotis, Ed.; Zacharia, Giorgos, Ed.

    2006-01-01

    In the field of computer aided language learning (CALL), there is a need for emphasizing the importance of the user. "User-Centered Computer Aided Language Learning" presents methodologies, strategies, and design approaches for building interfaces for a user-centered CALL environment, creating a deeper understanding of the opportunities and…

  14. Interactive computer aided technology, evolution in the design/manufacturing process

    NASA Technical Reports Server (NTRS)

    English, C. H.

    1975-01-01

    A powerful computer-operated three dimensional graphic system and associated auxiliary computer equipment used in advanced design, production design, and manufacturing was described. This system has made these activities more productive than when using older and more conventional methods to design and build aerospace vehicles. With the use of this graphic system, designers are now able to define parts using a wide variety of geometric entities, define parts as fully surface 3-dimensional models as well as "wire-frame" models. Once geometrically defined, the designer is able to take section cuts of the surfaced model and automatically determine all of the section properties of the planar cut, lightpen detect all of the surface patches and automatically determine the volume and weight of the part. Further, his designs are defined mathematically at a degree of accuracy never before achievable.

  15. Computer-Aided Design of Organic Host Architectures for Selective Chemosensors

    SciTech Connect

    Hay, Benjamin; Bryantsev, Vyacheslav S.

    2009-01-01

    Selective organic hosts provide the foundation for the development of many types of sensors. The deliberate design of host molecules with predetermined selectivity, however, remains a challenge in supramolecular chemistry. To address this issue we have developed a de novo structure-based design approach for the unbiased construction of complementary host architectures. This chapter summarizes recent progress including improvements on a computer software program, HostDesigner, specifically tailored to discover host architectures for small guest molecules. HostDesigner is capable of generating and evaluating millions of candidate structures in minutes on a desktop personal computer, allowing a user to rapidly identify three-dimensional architectures that are structurally organized for binding a targeted guest species. The efficacy of this computational methodology is illustrated with a search for cation hosts containing aliphatic ether oxygen groups and anion hosts containing urea groups.

  16. Computer program for design and performance analysis of navigation-aid power systems. Program documentation. Volume 1: Software requirements document

    NASA Technical Reports Server (NTRS)

    Goltz, G.; Kaiser, L. M.; Weiner, H.

    1977-01-01

    A computer program has been developed for designing and analyzing the performance of solar array/battery power systems for the U.S. Coast Guard Navigational Aids. This program is called the Design Synthesis/Performance Analysis (DSPA) Computer Program. The basic function of the Design Synthesis portion of the DSPA program is to evaluate functional and economic criteria to provide specifications for viable solar array/battery power systems. The basic function of the Performance Analysis portion of the DSPA program is to simulate the operation of solar array/battery power systems under specific loads and environmental conditions. This document establishes the software requirements for the DSPA computer program, discusses the processing that occurs within the program, and defines the necessary interfaces for operation.

  17. Potential Drug-Like Inhibitors of Group 1 Influenza Neuraminidase Identified through Computer-Aided Drug Design

    PubMed Central

    Durrant, Jacob D.; McCammon, J. Andrew

    2010-01-01

    Pandemic (H1N1) influenza poses an imminent threat. Nations have stockpiled inhibitors of the influenza protein neuraminidase in hopes of protecting their citizens, but drug-resistant strains have already emerged, and novel therapeutics are urgently needed. In the current work, the computer program AutoGrow is used to generate novel predicted neuraminidase inhibitors. Given the great flexibility of the neuraminidase active site, protein dynamics are also incorporated into the computer-aided drug-design process. Several potential inhibitors are identified that are predicted to bind neuraminidase better than currently approved drugs. PMID:20427241

  18. Computer-Aided Design and Rapid Prototyping–Assisted Contouring of Costal Cartilage Graft for Facial Reconstructive Surgery

    PubMed Central

    Lee, Shu Jin; Lee, Heow Pueh; Tse, Kwong Ming; Cheong, Ee Cherk; Lim, Siak Piang

    2012-01-01

    Complex 3-D defects of the facial skeleton are difficult to reconstruct with freehand carving of autogenous bone grafts. Onlay bone grafts are hard to carve and are associated with imprecise graft-bone interface contact and bony resorption. Autologous cartilage is well established in ear reconstruction as it is easy to carve and is associated with minimal resorption. In the present study, we aimed to reconstruct the hypoplastic orbitozygomatic region in a patient with left hemifacial microsomia using computer-aided design and rapid prototyping to facilitate costal cartilage carving and grafting. A three-step process of (1) 3-D reconstruction of the computed tomographic image, (2) mirroring the facial skeleton, and (3) modeling and rapid prototyping of the left orbitozygomaticomalar region and reconstruction template was performed. The template aided in donor site selection and extracorporeal contouring of the rib cartilage graft to allow for an accurate fit of the graft to the bony model prior to final fixation in the patient. We are able to refine the existing computer-aided design and rapid prototyping methods to allow for extracorporeal contouring of grafts and present rib cartilage as a good alternative to bone for autologous reconstruction. PMID:23730421

  19. Computer-aided design of curved surfaces with automatic model generation

    NASA Technical Reports Server (NTRS)

    Staley, S. M.; Jerard, R. B.; White, P. R.

    1980-01-01

    The design and visualization of three-dimensional objects with curved surfaces have always been difficult. The paper given below describes a computer system which facilitates both the design and visualization of such surfaces. The system enhances the design of these surfaces by virtue of various interactive techniques coupled with the application of B-Spline theory. Visualization is facilitated by including a specially built model-making machine which produces three-dimensional foam models. Thus, the system permits the designer to produce an inexpensive model of the object which is suitable for evaluation and presentation.

  20. Computer-Assisted Mandibular Reconstruction using a Patient-Specific Reconstruction Plate Fabricated with Computer-Aided Design and Manufacturing Techniques

    PubMed Central

    Wilde, Frank; Cornelius, Carl-Peter; Schramm, Alexander

    2014-01-01

    We investigated the workflow of computer-assisted mandibular reconstruction that was performed with a patient-specific mandibular reconstruction plate fabricated with computer-aided design and computer-aided manufacturing (CAD/CAM) techniques and a fibula flap. We assessed the feasibility of this technique from virtual planning to the completion of surgery. Computed tomography (CT) scans of a cadaveric skull and fibula were obtained for the virtual simulation of mandibular resection and reconstruction using ProPlan CMF software (Materialise®/DePuy Synthes®). The virtual model of the reconstructed mandible provided the basis for the computer-aided design of a patient-specific reconstruction plate that was milled from titanium using a five-axis milling machine and CAM techniques. CAD/CAM techniques were used for producing resection guides for mandibular resection and cutting guides for harvesting a fibula flap. Mandibular reconstruction was simulated in a cadaveric wet laboratory. No problems were encountered during the procedure. The plate was fixed accurately to the residual bone without difficulty. The fibula segments were attached to the plate rapidly and reliably. The fusion of preoperative and postoperative CT datasets demonstrated high reconstruction precision. Computer-assisted mandibular reconstruction with CAD/CAM-fabricated patient-specific reconstruction plates appears to be a promising approach for mandibular reconstruction. Clinical trials are required to determine whether these promising results can be translated into successful practice and what further developments are needed. PMID:25045420

  1. Determination of Optimal Parameters for Dual-Layer Cathode of Polymer Electrolyte Fuel Cell Using Computational Intelligence-Aided Design

    PubMed Central

    Chen, Yi; Huang, Weina; Peng, Bei

    2014-01-01

    Because of the demands for sustainable and renewable energy, fuel cells have become increasingly popular, particularly the polymer electrolyte fuel cell (PEFC). Among the various components, the cathode plays a key role in the operation of a PEFC. In this study, a quantitative dual-layer cathode model was proposed for determining the optimal parameters that minimize the over-potential difference and improve the efficiency using a newly developed bat swarm algorithm with a variable population embedded in the computational intelligence-aided design. The simulation results were in agreement with previously reported results, suggesting that the proposed technique has potential applications for automating and optimizing the design of PEFCs. PMID:25490761

  2. Computer-aided design for smoke management in atria and covered malls

    SciTech Connect

    Milke, J.A.; Mowrer, F.W.

    1994-12-31

    A computer model that can assist designers in evaluating a smoke management system for an atrium or a covered mall was developed recently. The algorithm, which is the result of an initial effort to adapt zone modeling for atrium applications, could become an ASHRAE design tool. Evolution into such a standard tool requires validation of the numerical algorithm to assess its appropriateness for evaluating smoke management systems in spaces with large volumes and tall ceilings.

  3. An Investigation into Computer Aided Drafting and Design (CADD) in the Saginaw Area from the Viewpoint of Mechanical Drafting and Design Employers.

    ERIC Educational Resources Information Center

    Irwin, John L.

    The extent to which computer-aided drafting and design (CADD) was being used in local businesses in Saginaw, Michigan, was investigated. Focuses of a literature review were types of CADD systems, categories of CADD users, and the symbiotic relationship between industry and education in providing CADD training. The survey questionnaire was…

  4. Computer Aided Instruction for a Course in Boolean Algebra and Logic Design. Final Report (Revised).

    ERIC Educational Resources Information Center

    Roy, Rob

    The use of computers to prepare deficient college and graduate students for courses that build upon previously acquired information would solve the growing problem of professors who must spend up to one third of their class time in review of material. But examination of students who were taught Boolean Algebra and Logic Design by means of Computer…

  5. New layer-based imaging and rapid prototyping techniques for computer-aided design and manufacture of custom dental restoration.

    PubMed

    Lee, M-Y; Chang, C-C; Ku, Y C

    2008-01-01

    Fixed dental restoration by conventional methods greatly relies on the skill and experience of the dental technician. The quality and accuracy of the final product depends mostly on the technician's subjective judgment. In addition, the traditional manual operation involves many complex procedures, and is a time-consuming and labour-intensive job. Most importantly, no quantitative design and manufacturing information is preserved for future retrieval. In this paper, a new device for scanning the dental profile and reconstructing 3D digital information of a dental model based on a layer-based imaging technique, called abrasive computer tomography (ACT) was designed in-house and proposed for the design of custom dental restoration. The fixed partial dental restoration was then produced by rapid prototyping (RP) and computer numerical control (CNC) machining methods based on the ACT scanned digital information. A force feedback sculptor (FreeForm system, Sensible Technologies, Inc., Cambridge MA, USA), which comprises 3D Touch technology, was applied to modify the morphology and design of the fixed dental restoration. In addition, a comparison of conventional manual operation and digital manufacture using both RP and CNC machining technologies for fixed dental restoration production is presented. Finally, a digital custom fixed restoration manufacturing protocol integrating proposed layer-based dental profile scanning, computer-aided design, 3D force feedback feature modification and advanced fixed restoration manufacturing techniques is illustrated. The proposed method provides solid evidence that computer-aided design and manufacturing technologies may become a new avenue for custom-made fixed restoration design, analysis, and production in the 21st century.

  6. New layer-based imaging and rapid prototyping techniques for computer-aided design and manufacture of custom dental restoration.

    PubMed

    Lee, M-Y; Chang, C-C; Ku, Y C

    2008-01-01

    Fixed dental restoration by conventional methods greatly relies on the skill and experience of the dental technician. The quality and accuracy of the final product depends mostly on the technician's subjective judgment. In addition, the traditional manual operation involves many complex procedures, and is a time-consuming and labour-intensive job. Most importantly, no quantitative design and manufacturing information is preserved for future retrieval. In this paper, a new device for scanning the dental profile and reconstructing 3D digital information of a dental model based on a layer-based imaging technique, called abrasive computer tomography (ACT) was designed in-house and proposed for the design of custom dental restoration. The fixed partial dental restoration was then produced by rapid prototyping (RP) and computer numerical control (CNC) machining methods based on the ACT scanned digital information. A force feedback sculptor (FreeForm system, Sensible Technologies, Inc., Cambridge MA, USA), which comprises 3D Touch technology, was applied to modify the morphology and design of the fixed dental restoration. In addition, a comparison of conventional manual operation and digital manufacture using both RP and CNC machining technologies for fixed dental restoration production is presented. Finally, a digital custom fixed restoration manufacturing protocol integrating proposed layer-based dental profile scanning, computer-aided design, 3D force feedback feature modification and advanced fixed restoration manufacturing techniques is illustrated. The proposed method provides solid evidence that computer-aided design and manufacturing technologies may become a new avenue for custom-made fixed restoration design, analysis, and production in the 21st century. PMID:18183523

  7. Computer-Aided Remote Driving

    NASA Technical Reports Server (NTRS)

    Wilcox, Brian H.

    1994-01-01

    System for remote control of robotic land vehicle requires only small radio-communication bandwidth. Twin video cameras on vehicle create stereoscopic images. Operator views cross-polarized images on two cathode-ray tubes through correspondingly polarized spectacles. By use of cursor on frozen image, remote operator designates path. Vehicle proceeds to follow path, by use of limited degree of autonomous control to cope with unexpected conditions. System concept, called "computer-aided remote driving" (CARD), potentially useful in exploration of other planets, military surveillance, firefighting, and clean-up of hazardous materials.

  8. A Pilot Computer-Aided Design and Manufacturing Curriculum that Promotes Engineering

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Elizabeth City State University (ECSU) is located in a community that is mostly rural in nature. The area is economically deprived when compared to the rest of the state. Many businesses lack the computerized equipment and skills needed to propel upward in today's technologically advanced society. This project will close the ever-widening gap between advantaged and disadvantaged workers as well as increase their participation with industry, NASA and/or other governmental agencies. Everyone recognizes computer technology as the catalyst for advances in design, prototyping, and manufacturing or the art of machining. Unprecedented quality control and cost-efficiency improvements are recognized through the use of computer technology. This technology has changed the manufacturing industry with advanced high-tech capabilities needed by NASA. With the ever-widening digital divide, we must continue to provide computer technology to those who are socio-economically disadvantaged.

  9. Advanced earth observation spacecraft computer-aided design software: Technical, user and programmer guide

    NASA Technical Reports Server (NTRS)

    Farrell, C. E.; Krauze, L. D.

    1983-01-01

    The IDEAS computer of NASA is a tool for interactive preliminary design and analysis of LSS (Large Space System). Nine analysis modules were either modified or created. These modules include the capabilities of automatic model generation, model mass properties calculation, model area calculation, nonkinematic deployment modeling, rigid-body controls analysis, RF performance prediction, subsystem properties definition, and EOS science sensor selection. For each module, a section is provided that contains technical information, user instructions, and programmer documentation.

  10. A Short Review of Chemical Reaction Database Systems, Computer-Aided Synthesis Design, Reaction Prediction and Synthetic Feasibility.

    PubMed

    Warr, Wendy A

    2014-06-01

    This article is the text for a pedagogical lecture to be given at the Strasbourg Summer School in Chemoinformatics in June 2104. It covers a very wide range of reaction topics including structure and reaction representation, reaction centers, atom-to-atom mapping, reaction retrieval systems, computer-aided synthesis design, retrosynthesis, reaction prediction and synthetic feasibility. In the time available the coverage of each topic can only be cursory; the main usefulness of this article to the research community is the extensive bibliography.

  11. Computer-aided design of peptide near infrared fluorescent probe for tumor diagnosis

    NASA Astrophysics Data System (ADS)

    Zhang, Congying; Gu, Yueqing

    2014-09-01

    Integrin αvβ3 receptors are expressed on activated endothelial cells during neovascularization to maintain tumor growth, so they become hot research tagets in cancer diagnosis. Peptides possess several attractive features when compared to protein and small molecule, such as small size and high structural compatibility with target proteins. Efficient design of high-affinity peptide ligands to Integrin αvβ3 receptors has been an important problem. Designed peptides in silico provide a valuable and high-selectivity peptide, meanwhile decrease the time of drug screening. In this study, we design peptide which can bind with integrin αvβ3 via computer, and then synthesis near infrared fluorescent probe. The characterization of this near infrared fluorescent probe was detected by UV. To investigate the tumor cell targeting of this probe, it was labeled with visible fluorescent dye Rhodamine B (RhB) for microscopy. To evaluate the targeting capability of this near infrared fluorescent probe, mice bearing integrin αvβ3 positive tumor xenografts were used. In vitro cellular experiments indicated that this probe have a clear binding affinity to αvβ3-positive tumor cells. In vivo experiments confirmed the receptor binding specificity of this probe. The peptide of computational design can bind with integrin αvβ3. Combined peptide near-infrared fluorescent probe with imaging technology use for clinical and tumor diagnosis have a greater development in future.

  12. Computer-Aided Design of Materials for use under High Temperature Operating Condition

    SciTech Connect

    Rajagopal, K. R.; Rao, I. J.

    2010-01-31

    The procedures in place for producing materials in order to optimize their performance with respect to creep characteristics, oxidation resistance, elevation of melting point, thermal and electrical conductivity and other thermal and electrical properties are essentially trial and error experimentation that tend to be tremendously time consuming and expensive. A computational approach has been developed that can replace the trial and error procedures in order that one can efficiently design and engineer materials based on the application in question can lead to enhanced performance of the material, significant decrease in costs and cut down the time necessary to produce such materials. The work has relevance to the design and manufacture of turbine blades operating at high operating temperature, development of armor and missiles heads; corrosion resistant tanks and containers, better conductors of electricity, and the numerous other applications that are envisaged for specially structured nanocrystalline solids. A robust thermodynamic framework is developed within which the computational approach is developed. The procedure takes into account microstructural features such as the dislocation density, lattice mismatch, stacking faults, volume fractions of inclusions, interfacial area, etc. A robust model for single crystal superalloys that takes into account the microstructure of the alloy within the context of a continuum model is developed. Having developed the model, we then implement in a computational scheme using the software ABAQUS/STANDARD. The results of the simulation are compared against experimental data in realistic geometries.

  13. The Design and Production of a Procedure Training Aid Using the Procedure Learning Format and the Computer Automated Page Layout (PLA) Routine. Technical Note 12-83.

    ERIC Educational Resources Information Center

    Terrell, William R.; And Others

    This report describes a field application of the Computer Automated Page Layout (PLA) system to the development of a procedure training aid for the SH-3D/H Helicopter, as part of the Training Analysis and Evaluation Group's (TAEG) ongoing development effort to provide tools for the design and publication of technical training aids in a format…

  14. Aerodynamic heating and surface temperatures on vehicles for computer-aided design studies

    NASA Technical Reports Server (NTRS)

    Dejarnette, F. R.; Kania, L. A.; Chitty, A.

    1983-01-01

    A computer subprogram has been developed to calculate aerodynamic and radiative heating rates and to determine surface temperatures by integrating the heating rates along the trajectory of a vehicle. Convective heating rates are calculated by applying the axisymmetric analogue to inviscid surface streamlines and using relatively simple techniques to calculate laminar, transitional, or turbulent heating rates. Options are provided for the selection of gas model, transition criterion, turbulent heating method, Reynolds Analogy factor, and entropy-layer swallowing effects. Heating rates are compared to experimental data, and the time history of surface temperatures are given for a high-speed trajectory. The computer subprogram is developed for preliminary design and mission analysis where parametric studies are needed at all speeds.

  15. VPIsystems industry training program on computer-aided design of fiber optic communication systems

    NASA Astrophysics Data System (ADS)

    Richter, Andre; Chan, David K. C.

    2002-05-01

    In industry today, professional Photonic Design Automation (PDA) tools are a necessity to enable fast development cycles for the design of optical components, systems and networks. The training of industrial personnel is of great importance in facilitating the full usability of PDA tools tailored to meet these demands. As the market leader of design and planning tools for system integrators and manufacturers of optical transmission systems and components, VPIsystems offers a set of two-day training courses. Attendees are taught on the design of metro WDM networks, high speed DWDM and ultra long-haul WDM systems, analogue and digital cable access systems, EDFA and Raman amplifiers, as well as active devices and circuits. The course work compromises of: (1) lectures on physical and modeling background topics; (2) creation of typical simulation scenarios and; (3) the analysis of results. This course work is facilitated by guided, hands-on lab exercises using VPIsystems software for a variety of practical design situations. In classes of up to 15, each attendee is allocated a computer, thereby allowing for a thorough and speedy training for the individual in all of the covered topics as well as for any extra-curriculum topics to be covered. Since 1999, more than 750 people have graduated from over 60 training courses. In this paper, details of VPIsystems Industry training program will be presented.

  16. PET/Computed Tomography in Breast Cancer: Can It Aid in Developing a Personalized Treatment Design?

    PubMed

    Suresh Malapure, Sumeet; Das, Kalpa Jyoti; Kumar, Rakesh

    2016-07-01

    PET with fluorodeoxyglucose (FDG-PET)/computed tomography (CT) imaging has significantly improved the management of breast cancer. FDG, however, is not tumor-specific and various image interpretation pitfalls may occur due to false-positive and false-negative causes of FDG uptake. PET/CT imaging with more specific radiopharmaceuticals may provide useful information about the pathophysiology in such cases. In the present article, we reviewed the use of whole-body FDG-PET/CT and (18)F-16α-17β-Fluoroestradiol PET/CT imaging to determine if these can be used to develop personalized treatment design for the better management of breast cancer. PMID:27321033

  17. Molecular modeling and computer aided drug design. Examples of their applications in medicinal chemistry.

    PubMed

    Ooms, F

    2000-02-01

    The development of new drugs with potential therapeutic applications is one of the most complex and difficult process in the pharmaceutical industry. Millions of dollars and man-hours are devoted to the discovery of new therapeutical agents. As, the activity of a drug is the result of a multitude of factors such as bioavailability, toxicity and metabolism, rational drug design has been utopias for centuries. Very recently, impressive technological advances in areas such as structural characterization of biomacromolecules, computer sciences and molecular biology have made rational drug design feasible. The aim of this review is to give an outline of studies in the field of medicinal chemistry in which molecular modeling has helped in the discovery process of new drugs. The emphasis will be on lead generation and optimization.

  18. Computer-Aided Optimization of Macroscopic Design Factors for Lithium-Ion Cell Performance and Life (Presentation)

    SciTech Connect

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

    2010-04-01

    Electric-drive vehicles enabled by power- and energy-dense batteries promise to improve vehicle efficiency and help reduce society's dependence on fossil fuels. Next generation plug-in hybrid vehicles and battery electric vehicles may also enable vehicles to be powered by electricity generated from clean, renewable resources; however, to increase the commercial viability of such vehicles, the cost, performance and life of the vehicles batteries must be further improved. This work illustrates a virtual design process to optimize the performance and life of large-format lithium ion batteries. Beginning with material-level kinetic and transport properties, the performance and life of multiple large-format cell designs are evaluated, demonstrating the impact of macroscopic design parameters such as foil thickness, tab location, and cell size and shape under various cycling conditions. Challenges for computer-aided engineering of large-format battery cells, such as competing requirements and objectives, are discussed.

  19. CAESY - COMPUTER AIDED ENGINEERING SYSTEM

    NASA Technical Reports Server (NTRS)

    Wette, M. R.

    1994-01-01

    Many developers of software and algorithms for control system design have recognized that current tools have limits in both flexibility and efficiency. Many forces drive the development of new tools including the desire to make complex system modeling design and analysis easier and the need for quicker turnaround time in analysis and design. Other considerations include the desire to make use of advanced computer architectures to help in control system design, adopt new methodologies in control, and integrate design processes (e.g., structure, control, optics). CAESY was developed to provide a means to evaluate methods for dealing with user needs in computer-aided control system design. It is an interpreter for performing engineering calculations and incorporates features of both Ada and MATLAB. It is designed to be reasonably flexible and powerful. CAESY includes internally defined functions and procedures, as well as user defined ones. Support for matrix calculations is provided in the same manner as MATLAB. However, the development of CAESY is a research project, and while it provides some features which are not found in commercially sold tools, it does not exhibit the robustness that many commercially developed tools provide. CAESY is written in C-language for use on Sun4 series computers running SunOS 4.1.1 and later. The program is designed to optionally use the LAPACK math library. The LAPACK math routines are available through anonymous ftp from research.att.com. CAESY requires 4Mb of RAM for execution. The standard distribution medium is a .25 inch streaming magnetic tape cartridge (QIC-24) in UNIX tar format. CAESY was developed in 1993 and is a copyrighted work with all copyright vested in NASA.

  20. Opportunities for Russian Nuclear Weapons Institute developing computer-aided design programs for pharmaceutical drug discovery. Final report

    SciTech Connect

    1996-09-23

    The goal of this study is to determine whether physicists at the Russian Nuclear Weapons Institute can profitably service the need for computer aided drug design (CADD) programs. The Russian physicists` primary competitive advantage is their ability to write particularly efficient code able to work with limited computing power; a history of working with very large, complex modeling systems; an extensive knowledge of physics and mathematics, and price competitiveness. Their primary competitive disadvantage is their lack of biology, and cultural and geographic issues. The first phase of the study focused on defining the competitive landscape, primarily through interviews with and literature searches on the key providers of CADD software. The second phase focused on users of CADD technology to determine deficiencies in the current product offerings, to understand what product they most desired, and to define the potential demand for such a product.

  1. Computer-aided rational design of novel EBF analogues with an aromatic ring.

    PubMed

    Wang, Shanshan; Sun, Yufeng; Du, Shaoqing; Qin, Yaoguo; Duan, Hongxia; Yang, Xinling

    2016-06-01

    Odorant binding proteins (OBPs) are important in insect olfactory recognition. These proteins bind specifically to insect semiochemicals and induce their seeking, mating, and alarm behaviors. Molecular docking and molecular dynamics simulations were performed to provide computational insight into the interaction mode between AgamOBP7 and novel (E)-β-farnesene (EBF) analogues with an aromatic ring. The ligand-binding cavity in OBP7 was found to be mostly hydrophobic due to the presence of several nonpolar residues. The interactions between the EBF analogues and the hydrophobic residues in the binding cavity increased in strength as the distance between them decreased. The EBF analogues with an N-methyl formamide or ester linkage had higher docking scores than those with an amide linkage. Moreover, delocalized π-π and electrostatic interactions were found to contribute significantly to the binding between the ligand benzene ring and nearby protein residues. To design new compounds with higher activity, four EBF analogues D1-D4 with a benzene ring were synthesized and evaluated based on their docking scores and binding affinities. D2, which had an N-methyl formamide group linkage, exhibited stronger binding than D1, which had an amide linkage. D4 exhibited particularly strong binding due to multiple hydrophobic interactions with the protein. This study provides crucial foundations for designing novel EBF analogues based on the OBP structure. Graphical abstract The design strategy of new EBF analogues based on the OBP7 structure. PMID:27251400

  2. Computer-aided rational design of novel EBF analogues with an aromatic ring.

    PubMed

    Wang, Shanshan; Sun, Yufeng; Du, Shaoqing; Qin, Yaoguo; Duan, Hongxia; Yang, Xinling

    2016-06-01

    Odorant binding proteins (OBPs) are important in insect olfactory recognition. These proteins bind specifically to insect semiochemicals and induce their seeking, mating, and alarm behaviors. Molecular docking and molecular dynamics simulations were performed to provide computational insight into the interaction mode between AgamOBP7 and novel (E)-β-farnesene (EBF) analogues with an aromatic ring. The ligand-binding cavity in OBP7 was found to be mostly hydrophobic due to the presence of several nonpolar residues. The interactions between the EBF analogues and the hydrophobic residues in the binding cavity increased in strength as the distance between them decreased. The EBF analogues with an N-methyl formamide or ester linkage had higher docking scores than those with an amide linkage. Moreover, delocalized π-π and electrostatic interactions were found to contribute significantly to the binding between the ligand benzene ring and nearby protein residues. To design new compounds with higher activity, four EBF analogues D1-D4 with a benzene ring were synthesized and evaluated based on their docking scores and binding affinities. D2, which had an N-methyl formamide group linkage, exhibited stronger binding than D1, which had an amide linkage. D4 exhibited particularly strong binding due to multiple hydrophobic interactions with the protein. This study provides crucial foundations for designing novel EBF analogues based on the OBP structure. Graphical abstract The design strategy of new EBF analogues based on the OBP7 structure.

  3. Computer-aided design of reflector antennas - The Green Bank Radio Telescope

    NASA Astrophysics Data System (ADS)

    Terada, Marco A. B.; Stutzman, Warren L.

    1998-03-01

    This paper presents an evaluation of the electrical performance of the Green Bank Telescope (GBT) reflector antenna, operating as single- and dual-offset configurations, as well as a general overview of the GBT system. The GBT dual-offset Gregorian configuration is designed for low cross polarization (XPOL) using the dual-offset reflector antenna (DORA) synthesis package code. The procedure implemented in DORA to upgrade an existing main reflector to a low cross-polarized dual-offset Gregorian reflector antenna is also described. All computed patterns were obtained with the parabolic reflector analysis code (PRAC) program, and with the commercial code GRASP7. The GBT radiation patterns and performance values indicate that low XPOL performance can be achieved with a dual-offset configuration, provided that a low XPOL feed is used. The GBT configuration is employed as a case example for the aforementioned procedure.

  4. Building a computer-aided design capability using a standard time share operating system

    NASA Technical Reports Server (NTRS)

    Sobieszczanski, J.

    1975-01-01

    The paper describes how an integrated system of engineering computer programs can be built using a standard commercially available operating system. The discussion opens with an outline of the auxiliary functions that an operating system can perform for a team of engineers involved in a large and complex task. An example of a specific integrated system is provided to explain how the standard operating system features can be used to organize the programs into a simple and inexpensive but effective system. Applications to an aircraft structural design study are discussed to illustrate the use of an integrated system as a flexible and efficient engineering tool. The discussion concludes with an engineer's assessment of an operating system's capabilities and desirable improvements.

  5. Design and experimental analysis of an advanced static VAR compensator with computer aided control.

    PubMed

    Irmak, Erdal; Bayındır, Ramazan; Köse, Ali

    2016-09-01

    This study presents integration of a real-time energy monitoring and control system with an advanced reactive power compensation unit based on fixed capacitor-thyristor controlled reactor (FC-TCR). Firing angles of the thyristors located in the FC-TCR are controlled by a microcontroller in order to keep the power factor within the limits. Electrical parameters of the system are measured by specially designed circuits and simultaneously transferred to the computer via a data acquisition board. Thus, real time data of the system can be observed through a visual user interface. The data obtained is not only analyzed for control process, but also regularly saved into a database. The system has been tested in laboratory conditions under different load characteristics and experimental results verified that the system successfully and accurately achieves compensation process against the all operational conditions.

  6. A Novel Paradigm for Computer-Aided Design: TRIZ-Based Hybridization of Topologically Optimized Density Distributions

    NASA Astrophysics Data System (ADS)

    Cardillo, A.; Cascini, G.; Frillici, F. S.; Rotini, F.

    In a recent project the authors have proposed the adoption of Optimization Systems [1] as a bridging element between Computer-Aided Innovation (CAI) and PLM to identify geometrical contradictions [2], a particular case of the TRIZ physical contradiction [3]. A further development of the research [4] has revealed that the solutions obtained from several topological optimizations can be considered as elementary customized modeling features for a specific design task. The topology overcoming the arising geometrical contradiction can be obtained through a manipulation of the density distributions constituting the conflicting pair. Already two strategies of density combination have been identified as capable to solve geometrical contradictions and several others are under extended testing. The paper illustrates the most recent results of the ongoing research mainly related to the extension of the algorithms from 2D to 3D design spaces. The whole approach is clarified by means of two detailed examples, where the proposed technique is compared with classical multi-goal optimization.

  7. Computer aided lexicography

    NASA Astrophysics Data System (ADS)

    Sklenář, Ivan; Kříž, Václav

    1990-11-01

    Programs with a natural-language user interface and text-processing programs require a vocabulary providing the mapping of the individual word form onto a lexeme, e.g. "says", "said", "saying"→"see". Examples of such programs are indexing programs for information retrieval, and spelling correctors for text-processing systems. The lexicographical task of such a computer vocabulary is especially difficult for Slavic languages, because their morphological structure is complex. An average Czech verb, for example, has 25 forms, and we have identified more than 100 paradigms for verbs. In order to support the creation of a Czech vocabulary, we have designed a system of programs for paradigm identification and derivation of words. The result of our effort is a vocabulary comprising 110 000 words and 1250 000 word forms. This vocabulary was used for the PASSAT system in the Czechoslovak Press Agency. This vocabulary may also be used in a spelling corrector. However, for such an application the vocabulary must be compressed into a compact form in order to shorten the access times. Compression is based on the paradigmatic structure of morphology which defines suffix sets for each word.

  8. Computer AIDS for Clinical Research Management and Control: General Analysis and Design

    PubMed Central

    Willard, Christopher G.; Gatewood, Laël C.; Ellis, Lynda B. M.

    1979-01-01

    Clinical research projects involve concurrent management of subjects, protocol, analysis and study. This complicated management problem could be aided by the use of computerized data systems. For most effective aid, such a system should consider all aspects of clinical research. We have analyzed clinical research tasks involving data collection, communication, and management and have used this task analysis to develop a system model for clinical research data management and control. The model deals with data control, study monitoring, user interfaces, report and analysis libraries, and study subject and support data bases. It may be used as a basis for computerized data system study and development. The model also indicates that the role of computerized systems in clinical research could be expanded into such areas as automatic report generation and control, process control aids, quality assurance monitoring, and study documentation.

  9. Solar chimney design: Investigating natural ventilation and cooling in offices with the aid of computer simulation

    NASA Astrophysics Data System (ADS)

    Angelis, Nikolaos

    Solar chimney design is investigated as a means of improving natural ventilation and passive cooling in office buildings. Existing scientific research and built precedents are generally limited literature review findings on various features of solar chimneys were categorised and used to develop a building simulation strategy. Using UK climatic data, simulations were performed on several computer models in order to investigate solar chimney performance during a single day period and an entire cooling season. Passive cooling with a solar chimney is possible but actual reduction in temperatures in most cases examined could be negligible. Cooling potential is increased on still, warm days, while the prospects for night cooling are further improved. A solar chimney may help reduce considerably the occurrence of resultant temperatures at or above the 25 C and 28 C thresholds. Solar chimney width, height, apertures and integral use of thermal mass are the most significant parameters for cooling. Simulation results showed that a solar chimney can increase significantly natural ventilation rates. Total ventilation rates may be increased by at least 22%. During still days a solar chimney can enhance ventilation rates by 36% or more. Stack ventilation through a solar chimney is typically 20% of cross ventilation during night time this may increase to at least 40-45% and on still days it may reach 100% of typical cross ventilation rates. Solar chimney induced stack ventilation and cross ventilation are interrelated. Resultant air flow patterns may have an important effect on convective heat transfers and thermal comfort. Climate and microclimate conditions should be an integral part of solar chimney design. Key aspects and recommendations regarding solar chimneys, passive cooling and natural ventilation are provided for design guidance and feedback in further research.

  10. Integrated Computer-Aided Drafting Instruction (ICADI).

    ERIC Educational Resources Information Center

    Chen, C. Y.; McCampbell, David H.

    Until recently, computer-aided drafting and design (CAD) systems were almost exclusively operated on mainframes or minicomputers and their cost prohibited many schools from offering CAD instruction. Today, many powerful personal computers are capable of performing the high-speed calculation and analysis required by the CAD application; however,…

  11. A 3D computer-aided design system applied to diagnosis and treatment planning in orthodontics and orthognathic surgery.

    PubMed

    Motohashi, N; Kuroda, T

    1999-06-01

    The purpose of this article is to describe a newly developed 3D computer-aided design (CAD) system for the diagnostic set-up of casts in orthodontic diagnosis and treatment planning, and its preliminary clinical applications. The system comprises a measuring unit which obtains 3D information from the dental model using laser scanning, and a personal computer to generate the 3D graphics. When measuring the 3D shape of the model, to minimize blind sectors, the model is scanned from two different directions with the slit-ray laser beam by rotating the mounting angle of the model on the measuring device. For computed simulation of tooth movement, the representative planes, defined by the anatomical reference points, are formed for each individual tooth and are arranged along a guideline descriptive of the individual arch form. Subsequently, the 3D shape is imparted to each of the teeth arranged on the representative plane to form an arrangement of the 3D profile. When necessary, orthognathic surgery can be simulated by moving the mandibular dental arch three-dimensionally to establish the optimum occlusal relationship. Compared with hand-made set-up models, the computed diagnostic cast has advantages such as high-speed processing and quantitative evaluation on the amount of 3D movement of the individual tooth relative to the craniofacial plane. Trial clinical applications demonstrated that the use of this system facilitated the otherwise complicated and time-consuming mock surgery for treatment planning in orthognathic surgery.

  12. Computer-aided drug discovery

    PubMed Central

    Bajorath, Jürgen

    2015-01-01

    Computational approaches are an integral part of interdisciplinary drug discovery research. Understanding the science behind computational tools, their opportunities, and limitations is essential to make a true impact on drug discovery at different levels. If applied in a scientifically meaningful way, computational methods improve the ability to identify and evaluate potential drug molecules, but there remain weaknesses in the methods that preclude naïve applications. Herein, current trends in computer-aided drug discovery are reviewed, and selected computational areas are discussed. Approaches are highlighted that aid in the identification and optimization of new drug candidates. Emphasis is put on the presentation and discussion of computational concepts and methods, rather than case studies or application examples. As such, this contribution aims to provide an overview of the current methodological spectrum of computational drug discovery for a broad audience. PMID:26949519

  13. Computer aided surface representation

    SciTech Connect

    Barnhill, R.E.

    1990-02-19

    The central research problem of this project is the effective representation, computation, and display of surfaces interpolating to information in three or more dimensions. If the given information is located on another surface, then the problem is to construct a surface defined on a surface''. Sometimes properties of an already defined surface are desired, which is geometry processing''. Visualization of multivariate surfaces is possible by means of contouring higher dimensional surfaces. These problems and more are discussed below. The broad sweep from constructive mathematics through computational algorithms to computer graphics illustrations is utilized in this research. The breadth and depth of this research activity makes this research project unique.

  14. Computer Aided Braille Trainer

    PubMed Central

    Sibert, Thomas W.

    1984-01-01

    The problems involved in teaching visually impaired persons to Braille are numerous. Training while the individual is still sighted and using a computer to assist is one way of shortening the learning curve. Such a solution is presented here.

  15. 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 ...

  16. Construction computer-aided engineering

    SciTech Connect

    Hayashi, T.; Yoshinaga, T.; Atkins, D.; Astleford, R.

    1987-01-01

    Hitachi Ltd. and Bechtel Power Corporation are presently designing nuclear power plants for Japanese utilities exclusively on three-dimensional computer-aided design and drafting (CADD) systems. To make these three-dimensional CADD models more effective for construction activities, Hitachi and Bechtel are jointly developing a software package that allows construction engineers and planners to effectively empty an area of the three-dimensional CADD model and rebuild it electronically to simulate, animate, and optimize the construction sequence and methodology. The components in the three-dimensional CADD model are placed as they would be for actual construction (i.e., piping spool pieces, skid-mounted systems, piping, and equipment modules, etc.). The construction engineer and planners can then select the components along with appropriate handling equipment and simulate/animate the actual construction sequence. After the construction sequence has been optimized, it is captured on videotape for use in the field. The results of the simulated activities are then passed on to computer program module (CPM) scheduling and work breakdown structure programs for accurate bottom-up construction activity planning and commodity tracking. This entire process can be iterated to an optimum solution before the actual construction begins. Once construction is in progress, the program can compare the actual status and allow resimulations for workarounds.

  17. Development of a Computer-Aided-Design-Based Geometry and Mesh Movement Algorithm for Three-Dimensional Aerodynamic Shape Optimization

    NASA Astrophysics Data System (ADS)

    Truong, Anh Hoang

    This thesis focuses on the development of a Computer-Aided-Design (CAD)-based geometry parameterization method and a corresponding surface mesh movement algorithm suitable for three-dimensional aerodynamic shape optimization. The geometry parameterization method includes a geometry control tool to aid in the construction and manipulation of a CAD geometry through a vendor-neutral application interface, CAPRI. It automates the tedious part of the construction phase involving data entry and provides intuitive and effective design variables that allow for both the flexibility and the precision required to control the movement of the geometry. The surface mesh movement algorithm, on the other hand, transforms an initial structured surface mesh to fit the new geometry using a discrete representation of the new CAD surface provided by CAPRI. Using a unique mapping procedure, the algorithm not only preserves the characteristics of the original surface mesh, but also guarantees that the new mesh points are on the CAD geometry. The new surface mesh is then smoothed in the parametric space before it is transformed back into three-dimensional space. The procedure is efficient in that all the processing is done in the parametric space, incurring minimal computational cost. The geometry parameterization and mesh movement tools are integrated into a three-dimensional shape optimization framework, with a linear-elasticity volume-mesh movement algorithm, a Newton-Krylov flow solver for the Euler equations, and a gradient-based optimizer. The validity and accuracy of the CAD-based optimization algorithm are demonstrated through a number of verification and optimization cases.

  18. Preconditioner and convergence study for the Quantum Computer Aided Design (QCAD) nonlinear poisson problem posed on the Ottawa Flat 270 design geometry.

    SciTech Connect

    Kalashnikova, Irina

    2012-05-01

    A numerical study aimed to evaluate different preconditioners within the Trilinos Ifpack and ML packages for the Quantum Computer Aided Design (QCAD) non-linear Poisson problem implemented within the Albany code base and posed on the Ottawa Flat 270 design geometry is performed. This study led to some new development of Albany that allows the user to select an ML preconditioner with Zoltan repartitioning based on nodal coordinates, which is summarized. Convergence of the numerical solutions computed within the QCAD computational suite with successive mesh refinement is examined in two metrics, the mean value of the solution (an L{sup 1} norm) and the field integral of the solution (L{sup 2} norm).

  19. Individualized Surgical Templates and Titanium Microplates for Le Fort I Osteotomy by Computer-Aided Design and Computer-Aided Manufacturing.

    PubMed

    He, Wei; Tian, Kaiyue; Xie, Xiaoyan; Wang, Xiaoxia; Li, Yang; Wang, Xing; Li, Zili

    2015-09-01

    The authors report the use of novel individualized surgical templates and titanium miniplates for Le Fort I osteotomy and evaluate the accuracy of this technique in vitro. Nine three-dimensional stereolithographic skull models were used to design the templates and titanium microplates and to simulate the operation. Cone beam computed tomography (CBCT) scans of the skulls were acquired preoperatively and were used to generate virtual models. The surgical plans were made based on three-dimensional cephalometric analyses, and osteotomies were then performed virtually. Cylinder-shaped markers were placed to permit the correct location of titanium screws, and individualized surgical templates were designed. The bony segments were then repositioned virtually according to the surgical plans to correct the skeletal deformities. Resin surgical templates were produced by stereolithography rapid prototyping and the titanium miniplates by three-dimensional cutting. Le Fort I osteotomy was performed under the guide of the surgical templates and fixed with the titanium miniplates. Postoperatively, CBCT scans of each skull model were taken, and the differences between the actual and planned surgical outcomes were measured by superimposing the planned and postoperative virtual models generated from CBCT images. The authors demonstrated that the average linear difference between the planned and actual outcomes was <1 mm and the average orientation difference was <1°. The individualized surgical templates and titanium microplates designed in this experimental study permitted the repositioning of the maxillary segment to the correct planned positions during Le Fort I osteotomy, making this technique a promising alternative to the conventional split method.

  20. Computer Aided Tests.

    ERIC Educational Resources Information Center

    Steinke, Elisabeth

    An approach to using the computer to assemble German tests is described. The purposes of the system would be: (1) an expansion of the bilingual lexical memory bank to list and store idioms of all degrees of difficulty, with frequency data and with complete and sophisticated retrieval possibility for assembly; (2) the creation of an…

  1. Computer aided surface representation

    SciTech Connect

    Barnhill, R E

    1987-11-01

    The aims of this research are the creation of new surface forms and the determination of geometric and physical properties of surfaces. The full sweep from constructive mathematics through the implementation of algorithms and the interactive computer graphics display of surfaces is utilized. Both three-dimensional and multi- dimensional surfaces are considered. Particular emphasis is given to the scientific computing solution of Department of Energy problems. The methods that we have developed and that we are proposing to develop allow applications such as: Producing smooth contour maps from measured data, such as weather maps. Modeling the heat distribution inside a furnace from sample measurements. Terrain modeling based on satellite pictures. The investigation of new surface forms includes the topics of triangular interpolants, multivariate interpolation, surfaces defined on surfaces and monotone and/or convex surfaces. The geometric and physical properties considered include contours, the intersection of surfaces, curvatures as a interrogation tool, and numerical integration.

  2. Computer aided surface representation

    SciTech Connect

    Barnhill, R.E.

    1991-04-02

    Modern computing resources permit the generation of large amounts of numerical data. These large data sets, if left in numerical form, can be overwhelming. Such large data sets are usually discrete points from some underlying physical phenomenon. Because we need to evaluate the phenomenon at places where we don't have data, a continuous representation (a surface'') is required. A simple example is a weather map obtained from a discrete set of weather stations. (For more examples including multi-dimensional ones, see the article by Dr. Rosemary Chang in the enclosed IRIS Universe). In order to create a scientific structure encompassing the data, we construct an interpolating mathematical surface which can evaluate at arbitrary locations. We can also display and analyze the results via interactive computer graphics. In our research we construct a very wide variety of surfaces for applied geometry problems that have sound theoretical foundations. However, our surfaces have the distinguishing feature that they are constructed to solve short or long term practical problems. This DOE-funded project has developed the premiere research team in the subject of constructing surfaces (3D and higher dimensional) that provide smooth representations of real scientific and engineering information, including state of the art computer graphics visualizations. However, our main contribution is in the development of fundamental constructive mathematical methods and visualization techniques which can be incorporated into a wide variety of applications. This project combines constructive mathematics, algorithms, and computer graphics, all applied to real problems. The project is a unique resource, considered by our peers to be a de facto national center for this type of research.

  3. Computer Aided Drug Design Approaches for Identification of Novel Autotaxin (ATX) Inhibitors.

    PubMed

    Vrontaki, Eleni; Melagraki, Georgia; Kaffe, Eleanna; Mavromoustakos, Thomas; Kokotos, George; Aidinis, Vassilis; Afantitis, Antreas

    2016-01-01

    Autotaxin (ATX) has become an attractive target with a huge pharmacological and pharmacochemical interest in LPA-related diseases and to date many small organic molecules have been explored as potential ATX inhibitors. As a useful aid in the various efforts of identifying novel effective ATX inhibitors, in silico methods can serve as an important and valuable tool. Especially, Virtual Screening (VS) has recently received increased attention due to the large datasets made available, the development of advanced VS techniques and the encouraging fact that VS has contributed to the discovery of several compounds that have either reached the market or entered clinical trials. Different techniques and workflows have been reported in literature with the goal to prioritize possible potent hits. In this review article several deployed virtual screening strategies for the identification of novel potent ATX inhibitors are described. PMID:26997151

  4. OPAL: Toward the Computer-Aided Design of Oncology Advice Systems

    PubMed Central

    Musen, Mark A.; Combs, David M.; Walton, Joan D.; Shortliffe, Edward H.; Fagan, Lawrence M.

    1986-01-01

    Tools that allow physicians to enter knowledge directly into computers will greatly facilitate the creation of medical expert systems. OPAL is the knowledge entry program for ONCOCIN, an expert system that assists in the management of cancer patients enrolled in clinical trials. OPAL uses computer graphics techniques to display knowledge about cancer treatment plans in a manner intuitive to physicians. Knowledge entered graphically into OPAL is automatically converted by the program to the format used internally by ONCOCIN. OPAL thus allows clinical experts with no special training in computer science to create complex medical knowledge bases. Visual representation of knowledge in a manner that is understandable to physicians may greatly expedite the development of certain classes of medical advice systems.

  5. Methodology of Computer-Aided Design of Variable Guide Vanes of Aircraft Engines

    ERIC Educational Resources Information Center

    Falaleev, Sergei V.; Melentjev, Vladimir S.; Gvozdev, Alexander S.

    2016-01-01

    The paper presents a methodology which helps to avoid a great amount of costly experimental research. This methodology includes thermo-gas dynamic design of an engine and its mounts, the profiling of compressor flow path and cascade design of guide vanes. Employing a method elaborated by Howell, we provide a theoretical solution to the task of…

  6. The large scale microelectronics Computer-Aided Design and Test (CADAT) system

    NASA Technical Reports Server (NTRS)

    Gould, J. M.

    1978-01-01

    The CADAT system consists of a number of computer programs written in FORTRAN that provide the capability to simulate, lay out, analyze, and create the artwork for large scale microelectronics. The function of each software component of the system is described with references to specific documentation for each software component.

  7. The role and application of data base management in integrated computer-aided design

    NASA Technical Reports Server (NTRS)

    Blackburn, C. L.; Storaasli, O. O.; Fulton, R. E.

    1982-01-01

    The need to marshal the extensive data that figure in design problems is underlined. An approach to managing engineering data for use in a computerized integrated design system is described. The approach is embodied in an experimental integrated software system that is used to demonstrate and evaluate such data management functions as storage, retrieval, query, manipulation, and modification. The development and organization of the experimental integrated design system and the application of the system to selected test problems are discussed, together with insights into data management issues gained from the study.

  8. Computer-aided design of a BPSK spread-spectrum chip set

    NASA Astrophysics Data System (ADS)

    Jain, Rajeev; Samueli, Henry; Yang, Paul T.; Chien, Charles; Chen, Gloria G.; Lau, Linda K.; Chung, Bong-Young; Cohen, Etan G.

    1992-01-01

    The design of a binary-phase shift-keyed (BPSK) spread-spectrum chip set with an integrated CAD environment called VANDA is described. VANDA uses the functional compiler concept to integrate system and physical designs, thus allowing complex high-performance integrated circuit chips to be implemented easily. Three functional compilers have been designed and implemented for the design of a spread-spectrum transceiver: a pseudonoise (PN) generator compiler, a direct digital frequency synthesizer (DDFS) compiler, and a Costas loop compiler. Three test chips for a BPSK digital intermediate frequency (IF) spread-spectrum system generated by these compilers have been fabricated and tested. Details of each of the functional compilers and the test chips are described. In addition, the measurement results for digital IF transceiver test boards constructed using these chips are presented.

  9. Merlin: Computer-Aided Oligonucleotide Design for Large Scale Genome Engineering with MAGE.

    PubMed

    Quintin, Michael; Ma, Natalie J; Ahmed, Samir; Bhatia, Swapnil; Lewis, Aaron; Isaacs, Farren J; Densmore, Douglas

    2016-06-17

    Genome engineering technologies now enable precise manipulation of organism genotype, but can be limited in scalability by their design requirements. Here we describe Merlin ( http://merlincad.org ), an open-source web-based tool to assist biologists in designing experiments using multiplex automated genome engineering (MAGE). Merlin provides methods to generate pools of single-stranded DNA oligonucleotides (oligos) for MAGE experiments by performing free energy calculation and BLAST scoring on a sliding window spanning the targeted site. These oligos are designed not only to improve recombination efficiency, but also to minimize off-target interactions. The application further assists experiment planning by reporting predicted allelic replacement rates after multiple MAGE cycles, and enables rapid result validation by generating primer sequences for multiplexed allele-specific colony PCR. Here we describe the Merlin oligo and primer design procedures and validate their functionality compared to OptMAGE by eliminating seven AvrII restriction sites from the Escherichia coli genome.

  10. Kinetic barriers in the isomerization of substituted ureas: implications for computer-aided drug design.

    PubMed

    Loeffler, Johannes R; Ehmki, Emanuel S R; Fuchs, Julian E; Liedl, Klaus R

    2016-05-01

    Urea derivatives are ubiquitously found in many chemical disciplines. N,N'-substituted ureas may show different conformational preferences depending on their substitution pattern. The high energetic barrier for isomerization of the cis and trans state poses additional challenges on computational simulation techniques aiming at a reproduction of the biological properties of urea derivatives. Herein, we investigate energetics of urea conformations and their interconversion using a broad spectrum of methodologies ranging from data mining, via quantum chemistry to molecular dynamics simulation and free energy calculations. We find that the inversion of urea conformations is inherently slow and beyond the time scale of typical simulation protocols. Therefore, extra care needs to be taken by computational chemists to work with appropriate model systems. We find that both knowledge-driven approaches as well as physics-based methods may guide molecular modelers towards accurate starting structures for expensive calculations to ensure that conformations of urea derivatives are modeled as adequately as possible. PMID:27272323

  11. CHARMM additive and polarizable force fields for biophysics and computer-aided drug design

    PubMed Central

    Vanommeslaeghe, K.

    2014-01-01

    Background Molecular Mechanics (MM) is the method of choice for computational studies of biomolecular systems owing to its modest computational cost, which makes it possible to routinely perform molecular dynamics (MD) simulations on chemical systems of biophysical and biomedical relevance. Scope of Review As one of the main factors limiting the accuracy of MD results is the empirical force field used, the present paper offers a review of recent developments in the CHARMM additive force field, one of the most popular bimolecular force fields. Additionally, we present a detailed discussion of the CHARMM Drude polarizable force field, anticipating a growth in the importance and utilization of polarizable force fields in the near future. Throughout the discussion emphasis is placed on the force fields’ parametrization philosophy and methodology. Major Conclusions Recent improvements in the CHARMM additive force field are mostly related to newly found weaknesses in the previous generation of additive force fields. Beyond the additive approximation is the newly available CHARMM Drude polarizable force field, which allows for MD simulations of up to 1 microsecond on proteins, DNA, lipids and carbohydrates. General Significance Addressing the limitations ensures the reliability of the new CHARMM36 additive force field for the types of calculations that are presently coming into routine computational reach while the availability of the Drude polarizable force fields offers a model that is an inherently more accurate model of the underlying physical forces driving macromolecular structures and dynamics. PMID:25149274

  12. Comparisons of Wilson-Fowler and Parametric Cubic Splines with the Curve-Fitting Algorithms of Several Computer-Aided Design Systems

    SciTech Connect

    Birchler, W.D.; Schilling, S.A.

    2001-02-01

    The purpose of this report is to demonstrate that modern computer-aided design (CAD), computer-aided manufacturing (CAM), and computer-aided engineering (CAE) systems can be used in the Department of Energy (DOE) Nuclear Weapons Complex (NWC) to design new and remodel old products, fabricate old and new parts, and reproduce legacy data within the inspection uncertainty limits. In this study, two two-dimensional splines are compared with several modern CAD curve-fitting modeling algorithms. The first curve-fitting algorithm is called the Wilson-Fowler Spline (WFS), and the second is called a parametric cubic spline (PCS). Modern CAD systems usually utilize either parametric cubic and/or B-splines.

  13. Computer Aided Drafting. Instructor's Guide.

    ERIC Educational Resources Information Center

    Henry, Michael A.

    This guide is intended for use in introducing students to the operation and applications of computer-aided drafting (CAD) systems. The following topics are covered in the individual lessons: understanding CAD (CAD versus traditional manual drafting and care of software and hardware); using the components of a CAD system (primary and other input…

  14. Computer Aided Design of Advanced Turbine Airfoil Alloys for Industrial Gas Turbines in Coal Fired Environments

    SciTech Connect

    G.E. Fuchs

    2007-12-31

    Recent initiatives for fuel flexibility, increased efficiency and decreased emissions in power generating industrial gas turbines (IGT's), have highlighted the need for the development of techniques to produce large single crystal or columnar grained, directionally solidified Ni-base superalloy turbine blades and vanes. In order to address the technical difficulties of producing large single crystal components, a program has been initiated to, using computational materials science, better understand how alloy composition in potential IGT alloys and solidification conditions during processing, effect castability, defect formation and environmental resistance. This program will help to identify potential routes for the development of high strength, corrosion resistant airfoil/vane alloys, which would be a benefit to all IGT's, including small IGT's and even aerospace gas turbines. During the first year, collaboration with Siemens Power Corporation (SPC), Rolls-Royce, Howmet and Solar Turbines has identified and evaluated about 50 alloy compositions that are of interest for this potential application. In addition, alloy modifications to an existing alloy (CMSX-4) were also evaluated. Collaborating with SPC and using computational software at SPC to evaluate about 50 alloy compositions identified 5 candidate alloys for experimental evaluation. The results obtained from the experimentally determined phase transformation temperatures did not compare well to the calculated values in many cases. The effects of small additions of boundary strengtheners (i.e., C, B and N) to CMSX-4 were also examined. The calculated phase transformation temperatures were somewhat closer to the experimentally determined values than for the 5 candidate alloys, discussed above. The calculated partitioning coefficients were similar for all of the CMSX-4 alloys, similar to the experimentally determined segregation behavior. In general, it appears that computational materials science has become a

  15. Computer Aided Design of Ka-Band Waveguide Power Combining Architectures for Interplanetary Spacecraft

    NASA Technical Reports Server (NTRS)

    Vaden, Karl R.

    2006-01-01

    Communication systems for future NASA interplanetary spacecraft require transmitter power ranging from several hundred watts to kilowatts. Several hybrid junctions are considered as elements within a corporate combining architecture for high power Ka-band space traveling-wave tube amplifiers (TWTAs). This report presents the simulated transmission characteristics of several hybrid junctions designed for a low loss, high power waveguide based power combiner.

  16. A semi-automatic computer-aided method for surgical template design

    NASA Astrophysics Data System (ADS)

    Chen, Xiaojun; Xu, Lu; Yang, Yue; Egger, Jan

    2016-02-01

    This paper presents a generalized integrated framework of semi-automatic surgical template design. Several algorithms were implemented including the mesh segmentation, offset surface generation, collision detection, ruled surface generation, etc., and a special software named TemDesigner was developed. With a simple user interface, a customized template can be semi- automatically designed according to the preoperative plan. Firstly, mesh segmentation with signed scalar of vertex is utilized to partition the inner surface from the input surface mesh based on the indicated point loop. Then, the offset surface of the inner surface is obtained through contouring the distance field of the inner surface, and segmented to generate the outer surface. Ruled surface is employed to connect inner and outer surfaces. Finally, drilling tubes are generated according to the preoperative plan through collision detection and merging. It has been applied to the template design for various kinds of surgeries, including oral implantology, cervical pedicle screw insertion, iliosacral screw insertion and osteotomy, demonstrating the efficiency, functionality and generality of our method.

  17. A semi-automatic computer-aided method for surgical template design

    PubMed Central

    Chen, Xiaojun; Xu, Lu; Yang, Yue; Egger, Jan

    2016-01-01

    This paper presents a generalized integrated framework of semi-automatic surgical template design. Several algorithms were implemented including the mesh segmentation, offset surface generation, collision detection, ruled surface generation, etc., and a special software named TemDesigner was developed. With a simple user interface, a customized template can be semi- automatically designed according to the preoperative plan. Firstly, mesh segmentation with signed scalar of vertex is utilized to partition the inner surface from the input surface mesh based on the indicated point loop. Then, the offset surface of the inner surface is obtained through contouring the distance field of the inner surface, and segmented to generate the outer surface. Ruled surface is employed to connect inner and outer surfaces. Finally, drilling tubes are generated according to the preoperative plan through collision detection and merging. It has been applied to the template design for various kinds of surgeries, including oral implantology, cervical pedicle screw insertion, iliosacral screw insertion and osteotomy, demonstrating the efficiency, functionality and generality of our method. PMID:26843434

  18. Computer Aided Learning of Mathematics: Software Evaluation

    ERIC Educational Resources Information Center

    Yushau, B.; Bokhari, M. A.; Wessels, D. C. J.

    2004-01-01

    Computer Aided Learning of Mathematics (CALM) has been in use for some time in the Prep-Year Mathematics Program at King Fahd University of Petroleum & Minerals. Different kinds of software (both locally designed and imported) have been used in the quest of optimizing the recitation/problem session hour of the mathematics classes. This paper…

  19. SensiPath: computer-aided design of sensing-enabling metabolic pathways.

    PubMed

    Delépine, Baudoin; Libis, Vincent; Carbonell, Pablo; Faulon, Jean-Loup

    2016-07-01

    Genetically-encoded biosensors offer a wide range of opportunities to develop advanced synthetic biology applications. Circuits with the ability of detecting and quantifying intracellular amounts of a compound of interest are central to whole-cell biosensors design for medical and environmental applications, and they also constitute essential parts for the selection and regulation of high-producer strains in metabolic engineering. However, the number of compounds that can be detected through natural mechanisms, like allosteric transcription factors, is limited; expanding the set of detectable compounds is therefore highly desirable. Here, we present the SensiPath web server, accessible at http://sensipath.micalis.fr SensiPath implements a strategy to enlarge the set of detectable compounds by screening for multi-step enzymatic transformations converting non-detectable compounds into detectable ones. The SensiPath approach is based on the encoding of reactions through signature descriptors to explore sensing-enabling metabolic pathways, which are putative biochemical transformations of the target compound leading to known effectors of transcription factors. In that way, SensiPath enlarges the design space by broadening the potential use of biosensors in synthetic biology applications.

  20. Modified optimal control pilot model for computer-aided design and analysis

    NASA Technical Reports Server (NTRS)

    Davidson, John B.; Schmidt, David K.

    1992-01-01

    This paper presents the theoretical development of a modified optimal control pilot model based upon the optimal control model (OCM) of the human operator developed by Kleinman, Baron, and Levison. This model is input compatible with the OCM and retains other key aspects of the OCM, such as a linear quadratic solution for the pilot gains with inclusion of control rate in the cost function, a Kalman estimator, and the ability to account for attention allocation and perception threshold effects. An algorithm designed for each implementation in current dynamic systems analysis and design software is presented. Example results based upon the analysis of a tracking task using three basic dynamic systems are compared with measured results and with similar analyses performed with the OCM and two previously proposed simplified optimal pilot models. The pilot frequency responses and error statistics obtained with this modified optimal control model are shown to compare more favorably to the measured experimental results than the other previously proposed simplified models evaluated.

  1. Computer-aided osteotomy design for harvesting autologous bone grafts in reconstructive surgery

    NASA Astrophysics Data System (ADS)

    Krol, Zdzislaw; Zerfass, Peter; von Rymon-Lipinski, Bartosz; Jansen, Thomas; Hauck, Wolfgang; Zeilhofer, Hans-Florian U.; Sader, Robert; Keeve, Erwin

    2001-05-01

    Autologous grafts serve as the standard grafting material in the treatment of maxillofacial bone tumors, traumatic defects or congenital malformations. The pre-selection of a donor site depends primarily on the morphological fit of the available bone mass and the shape of the part that has to be transplanted. To achieve sufficient incorporation of the autograft into the host bone, precise planning and simulation of the surgical intervention based on 3D CT studies is required. This paper presents a method to identify an optimal donor site by performing an optimization of appropriate similarity measures between donor region and a given transplant. At the initial stage the surgeon has to delineate the osteotomy border lines in the template CT data set and to define a set of constraints for the optimization of appropriate similarity measures between donor region and a given transplant. At the initial stage the surgeon has to delineate the osteotomy border lines in the template CT data set and to define a set of constraints for the optimization task in the donor site CT data set. The following fully automatic optimization stage delivers a set of sub-optimal and optimal donor sites for a given template. All generated solutions can be explored interactively on the computer display using an efficient graphical interface. Reconstructive operations supported by our system were performed on 28 patients. We found that the operation time can be considerably shortened by this approach.

  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. ''Beauty of Wholeness and Beauty of Partiality.'' New Terms Defining the Concept of Beauty in Architecture in Terms of Sustainability and Computer Aided Design

    ERIC Educational Resources Information Center

    Farid, Ayman A.; Zaghloul, Weaam M.; Dewidar, Khaled M.

    2014-01-01

    The great shift in sustainability and computer aided design in the field of architecture caused a remarkable change in the architecture philosophy, new aspects of beauty and aesthetic values are being introduced, and traditional definitions for beauty cannot fully cover this aspects, which causes a gap between; new architecture works criticism and…

  4. 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)…

  5. An interactive program for computer-aided map design, display, and query: EMAPKGS2

    USGS Publications Warehouse

    Pouch, G.W.

    1997-01-01

    EMAPKGS2 is a user-friendly, PC-based electronic mapping tool for use in hydrogeologic exploration and appraisal. EMAPKGS2 allows the analyst to construct maps interactively from data stored in a relational database, perform point-oriented spatial queries such as locating all wells within a specified radius, perform geographic overlays, and export the data to other programs for further analysis. EMAPKGS2 runs under Microsoft?? Windows??? 3.1 and compatible operating systems. EMAPKGS2 is a public domain program available from the Kansas Geological Survey. EMAPKGS2 is the centerpiece of WHEAT, the Windows-based Hydrogeologic Exploration and Appraisal Toolkit, a suite of user-friendly Microsoft?? Windows??? programs for natural resource exploration and management. The principal goals in development of WHEAT have been ease of use, hardware independence, low cost, and end-user extensibility. WHEAT'S native data format is a Microsoft?? Access?? database. WHEAT stores a feature's geographic coordinates as attributes so they can be accessed easily by the user. The WHEAT programs are designed to be used in conjunction with other Microsoft?? Windows??? software to allow the natural resource scientist to perform work easily and effectively. WHEAT and EMAPKGS have been used at several of Kansas' Groundwater Management Districts and the Kansas Geological Survey on groundwater management operations, groundwater modeling projects, and geologic exploration projects. ?? 1997 Elsevier Science Ltd.

  6. Computer-aided design of a novel ligand for retinoic acid receptor in cancer chemotherapy

    NASA Astrophysics Data System (ADS)

    Silva, Carlos H. T. P.; Leopoldino, Andreia M.; Silva, Eloiza H. T.; Espinoza, V. A. A.; Taft, C. A.

    The isotypes of RAR and RXR are retinoic acid and retinoid X acid receptors, respectively, whose ligand-binding domain contains the ligand-dependent activation function, with distinct pharmacological targets for retinoids, involved in the treatment of various cancers and skin diseases. Due to the major challenge which cancer treatment and cure still imposes after many decades to the international scientific community, there is actually considerable interest in new ligands with increased bioactivity. We have focused on the retinoid acid receptor, which is considered an interesting target for drug design. In this work, we carried out density functional geometry optimizations and different docking procedures. We performed screening in a large database (hundreds of thousands of molecules which we optimized at the AM1 level) yielding a set of potential bioactive ligands. A new ligand was selected and optimized at the B3LYP/6-31G* level. A flexible docking program was used to investigate the interactions between the receptor and the new ligand. The result of this work is compared with several crystallographic ligands of RAR. Our theoretically more bioactive new ligand indicates stronger and more hydrogen bonds as well as hydrophobic interactions with the receptor.

  7. A computer aided design approach for deep water tension leg platforms

    SciTech Connect

    Johnson, C.P.

    1994-12-31

    In this research, a software package was developed under the sponsorship of the Offshore Technology Research Center that is funded by the National Science Foundation and administered by The University of Texas at Austin and Texas A and M University. This software package (Johnson (1993)) was especially conceived for educational or research purposes with emphasis on user interfaces, automatic data generation and graphical display. As a result, a state-of-the-art workstation approach was developed that incorporates sound analysis procedures for deep water Tension Leg Platforms (TLPs). The TLP program (OTRC-TLP-2D93) is easy to use -- yet it is capable of producing real time graphical simulation of the structural response of TLPs in deep water. Several options are available for treating structural nonlinearities as well as nonlinearities in the forcing function based on Morison`s equation. The formulation is based on a two-dimensional model and accounts for a fully coupled analysis of the hull and tendons. The software is designed to handle wave, wind and deep currents with a rich set of user selectable options. General considerations for the software package and the underlying theory are presented. Numerical examples for a TLP subjected to wave, wind and current at an ocean depth of 5,000 feet are presented showing how the problem can be analyzed in a user friendly environment, complimented by the graphical interface developed.

  8. Development of problem-oriented software packages for numerical studies and computer-aided design (CAD) of gyrotrons

    NASA Astrophysics Data System (ADS)

    Damyanova, M.; Sabchevski, S.; Zhelyazkov, I.; Vasileva, E.; Balabanova, E.; Dankov, P.; Malinov, P.

    2016-03-01

    Gyrotrons are the most powerful sources of coherent CW (continuous wave) radiation in the frequency range situated between the long-wavelength edge of the infrared light (far-infrared region) and the microwaves, i.e., in the region of the electromagnetic spectrum which is usually called the THz-gap (or T-gap), since the output power of other devices (e.g., solid-state oscillators) operating in this interval is by several orders of magnitude lower. In the recent years, the unique capabilities of the sub-THz and THz gyrotrons have opened the road to many novel and future prospective applications in various physical studies and advanced high-power terahertz technologies. In this paper, we present the current status and functionality of the problem-oriented software packages (most notably GYROSIM and GYREOSS) used for numerical studies, computer-aided design (CAD) and optimization of gyrotrons for diverse applications. They consist of a hierarchy of codes specialized to modelling and simulation of different subsystems of the gyrotrons (EOS, resonant cavity, etc.) and are based on adequate physical models, efficient numerical methods and algorithms.

  9. Computer-aided design provisionalization and implant insertion combined with optical scanning of plaster casts and computed tomography data

    PubMed Central

    Hara, Shingo; Mitsugi, Masaharu; Kanno, Takahiro; Tatemoto, Yukihiro

    2014-01-01

    The conventional implant prosthesis planning process currently involves confirmation of two-dimensional anatomical findings or the quantity and quality of bones using panoramic X-ray images. The introduction of computed tomography (CT) into the field has enabled the previously impossible confirmation of three-dimensional findings, making implant planning in precise locations possible. However, artifacts caused by the presence of metal prostheses can become problematic and can result in obstacles to diagnosis and implant planning. The most updated version of SimPlant® Pro has made it possible to integrate plaster cast images with CT data using optical scanning. Using this function, the obstacles created by metal prostheses are eliminated, facilitating implant planning at the actual intraoral location. Furthermore, a SurgiGuide® based on individual patient information can be created on plaster casts, resulting in easier and more precise implant insertion. PMID:24987602

  10. Design of a high-sensitivity classifier based on a genetic algorithm: application to computer-aided diagnosis

    NASA Astrophysics Data System (ADS)

    Sahiner, Berkman; Chan, Heang-Ping; Petrick, Nicholas; Helvie, Mark A.; Goodsitt, Mitchell M.

    1998-10-01

    -9155/43/10/014/img3.gif" ALIGN="MIDDLE"/>, although the latter provided a higher total area under the ROC curve. By setting an appropriate decision threshold, the high-sensitivity classifier and correctly identified 61% and 34% of the benign masses respectively without missing any malignant masses. Our results show that the choice of the feature selection technique is important in computer-aided diagnosis, and that the GA may be a useful tool for designing classifiers for lesion characterization.

  11. Computer-aided lens assembly.

    PubMed

    Tomlinson, Richard; Alcock, Rob; Petzing, Jon; Coupland, Jeremy

    2004-01-20

    We propose a computer-aided method of lens manufacture that allows assembly, adjustment, and test phases to be run concurrently until an acceptable level of optical performance is reached. Misalignment of elements within a compound lens is determined by a comparison of the results of physical ray tracing by use of an array of Gaussian laser beams with numerically obtained geometric ray traces. An estimate of misalignment errors is made, and individual elements are adjusted in an iterative manner until performance criteria are achieved. The method is illustrated for the alignment of an air-spaced doublet. PMID:14765916

  12. Evaluation of computer-aided foundation design techniques for fossil fuel power plants. Final report. [Includes list of firms involved, equipment, software, etc

    SciTech Connect

    Kulhawy, F.H.; Dill, J.C.; Trautmann, C.H.

    1984-11-01

    The use of an integrated computer-aided drafting and design system for fossil fuel power plant foundations would offer utilities considerable savings in engineering costs and design time. The technology is available, but research is needed to develop software, a common data base, and data management procedures. An integrated CADD system suitable for designing power plant foundations should include the ability to input, display, and evaluate geologic, geophysical, geotechnical, and survey field data; methods for designing piles, mats, footings, drilled shafts, and other foundation types; and the capability of evaluating various load configurations, soil-structure interactions, and other construction factors that influence design. Although no such integrated system exists, the survey of CADD techniques showed that the technology is available to computerize the whole foundation design process, from single-foundation analysis under single loads to three-dimensional analysis under earthquake loads. The practices of design firms using CADD technology in nonutility applications vary widely. Although all the firms surveyed used computer-aided drafting, only two used computer graphics in routine design procedures, and none had an integrated approach to using CADD for geotechnical engineering. All the firms had developed corporate policies related to system security, supervision, overhead allocation, training, and personnel compensation. A related EPRI project RP2514, is developing guidelines for applying CADD systems to entire generating-plant construction projects. 4 references, 6 figures, 6 tables.

  13. Computer Aided Drafting Workshop. Workshop Booklet.

    ERIC Educational Resources Information Center

    Goetsch, David L.

    This mini-course and article are presentations from a workshop on computer-aided drafting. The purpose of the mini-course is to assist drafting instructors in updating their occupational knowledge to include computer-aided drafting (CAD). Topics covered in the course include general computer information, the computer in drafting, CAD terminology,…

  14. Methods of the computer-aided statistical analysis of microcircuits

    NASA Astrophysics Data System (ADS)

    Beliakov, Iu. N.; Kurmaev, F. A.; Batalov, B. V.

    Methods that are currently used for the computer-aided statistical analysis of microcircuits at the design stage are summarized. In particular, attention is given to methods for solving problems in statistical analysis, statistical planning, and factorial model synthesis by means of irregular experimental design. Efficient ways of reducing the computer time required for statistical analysis and numerical methods of microcircuit analysis are proposed. The discussion also covers various aspects of the organization of computer-aided microcircuit modeling and analysis systems.

  15. EGRAM- ECHELLE SPECTROGRAPH DESIGN AID

    NASA Technical Reports Server (NTRS)

    Dantzler, A. A.

    1994-01-01

    EGRAM aids in the design of spectrographic systems that utilize an echelle-first order cross disperser combination. This optical combination causes a two dimensional echellogram to fall on a detector. EGRAM describes the echellogram with enough detail to allow the user to effectively judge the feasibility of the spectrograph's design. By iteratively altering system parameters, the desired echellogram can be achieved without making a physical model. EGRAM calculates system parameters which are accurate to the first order and compare favorably to results from ray tracing techniques. The spectrographic system modelled by EGRAM consists of an entrance aperture, collimator, echelle, cross dispersion grating, focusing options, and a detector. The system is assumed to be free of aberrations and the echelle, cross disperser, and detector should be planar. The EGRAM program is menu driven and has a HELP facility. The user is prompted for information such as minimum and maximum wavelengths, slit dimensions, ruling frequencies, detector geometry, and angle of incidence. EGRAM calculates the resolving power and range of order numbers covered by the echellogram. A numerical map is also produced. This tabulates the order number, slit bandpass, and high/middle/low wavelengths. EGRAM can also compute the centroid coordinates of a specific wavelength and order (or vice versa). EGRAM is written for interactive execution and is written in Microsoft BASIC A. It has been implemented on an IBM PC series computer operating under DOS. EGRAM was developed in 1985.

  16. U.S. aerospace industry opinion of the effect of computer-aided prediction-design technology on future wind-tunnel test requirements for aircraft development programs

    NASA Technical Reports Server (NTRS)

    Treon, S. L.

    1979-01-01

    A survey of the U.S. aerospace industry in late 1977 suggests that there will be an increasing use of computer-aided prediction-design technology (CPD Tech) in the aircraft development process but that, overall, only a modest reduction in wind-tunnel test requirements from the current level is expected in the period through 1995. Opinions were received from key spokesmen in 23 of the 26 solicited major companies or corporate divisions involved in the design and manufacture of nonrotary wing aircraft. Development programs for nine types of aircraft related to test phases and wind-tunnel size and speed range were considered.

  17. Computer-Aided Treatment Design of a Distal Upper Extremity Soft Tissue Tumor with Electron Beam Radiotherapy.

    PubMed

    Li, Chun; Crawford, Susan; Mundt, A J; Vijayakumar, S

    2015-01-01

    We present here a novel approach for the planning and treatment of a distal upper extremity soft tissue tumor. Utilizing computed tomography (CT) based electron dose calculations, a customized compensating wax bolus was designed in order to deliver sufficient dose coverage to the tumor volume while sparing the draining lymphatics of the patient's hand and digits. A clinical case is presented as well as the design and construction of the compensator. Outcome and clinical implications are discussed.

  18. Computer aided system engineering for space construction

    NASA Technical Reports Server (NTRS)

    Racheli, Ugo

    1989-01-01

    This viewgraph presentation covers the following topics. Construction activities envisioned for the assembly of large platforms in space (as well as interplanetary spacecraft and bases on extraterrestrial surfaces) require computational tools that exceed the capability of conventional construction management programs. The Center for Space Construction is investigating the requirements for new computational tools and, at the same time, suggesting the expansion of graduate and undergraduate curricula to include proficiency in Computer Aided Engineering (CAE) though design courses and individual or team projects in advanced space systems design. In the center's research, special emphasis is placed on problems of constructability and of the interruptability of planned activity sequences to be carried out by crews operating under hostile environmental conditions. The departure point for the planned work is the acquisition of the MCAE I-DEAS software, developed by the Structural Dynamics Research Corporation (SDRC), and its expansion to the level of capability denoted by the acronym IDEAS**2 currently used for configuration maintenance on Space Station Freedom. In addition to improving proficiency in the use of I-DEAS and IDEAS**2, it is contemplated that new software modules will be developed to expand the architecture of IDEAS**2. Such modules will deal with those analyses that require the integration of a space platform's configuration with a breakdown of planned construction activities and with a failure modes analysis to support computer aided system engineering (CASE) applied to space construction.

  19. Present capabilities and future requirements for computer-aided geometric modeling in the design and manufacture of gas turbine

    NASA Technical Reports Server (NTRS)

    Caille, E.; Propen, M.; Hoffman, A.

    1984-01-01

    Gas turbine engine design requires the ability to rapidly develop complex structures which are subject to severe thermal and mechanical operating loads. As in all facets of the aerospace industry, engine designs are constantly driving towards increased performance, higher temperatures, higher speeds, and lower weight. The ability to address such requirements in a relatively short time frame has resulted in a major thrust towards integrated design/analysis/manufacturing systems. These computer driven graphics systems represent a unique challenge, with major payback opportunities if properly conceived, implemented, and applied.

  20. 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…

  1. Quality Indexing with Computer-Aided Lexicography.

    ERIC Educational Resources Information Center

    Buchan, R. L.

    1992-01-01

    Discussion of computer-aided indexing activity focuses on examples from projects at the National Aeronautics and Space Administration (NASA). Standardization and quality in providing subject access to databases are considered; and computer-aided lexicography, including thesaurus construction, access vocabulary, definitions preparation,…

  2. Formative Assessment using Computer-Aided Assessment.

    ERIC Educational Resources Information Center

    Lawson, Duncan

    1999-01-01

    Describes how computer-aided assessment can provide a means of preserving formative assessment within the curriculum at a fraction of the time-cost involved with written work. Illustrates a variety of computer-aided assessment styles. (Author/ASK)

  3. New Paradigms for Computer Aids to Invention.

    ERIC Educational Resources Information Center

    Langston, M. Diane

    Many people are interested in computer aids to rhetorical invention and want to know how to evaluate an invention aid, what the criteria are for a good one, and how to assess the trade-offs involved in buying one product or another. The frame of reference for this evaluation is an "old paradigm," which treats the computer as if it were paper, but…

  4. Telerobotic workstation design aid

    NASA Technical Reports Server (NTRS)

    Corker, K.; Hudlicka, E.; Young, D.; Cramer, N.

    1989-01-01

    Telerobot systems are being developed to support a number of space mission applications. In low earth orbit, telerobots and teleoperated manipulators will be used in shuttle operations and space station construction/maintenance. Free flying telerobotic service vehicles will be used at low and geosynchronous orbital operations. Rovers and autonomous vehicles will be equipped with telerobotic devices in planetary exploration. In all of these systems, human operators will interact with the robot system at varied levels during the scheduled operations. The human operators may be in either orbital or ground-based control systems. To assure integrated system development and maximum utility across these systems, designers must be sensitive to the constraints and capabilities that the human brings to system operation and must be assisted in applying these human factors to system development. The simulation and analysis system is intended to serve the needs of system analysis/designers as an integrated workstation in support of telerobotic design.

  5. The design and analysis of simple low speed flap systems with the aid of linearized theory computer programs

    NASA Technical Reports Server (NTRS)

    Carlson, Harry W.

    1985-01-01

    The purpose here is to show how two linearized theory computer programs in combination may be used for the design of low speed wing flap systems capable of high levels of aerodynamic efficiency. A fundamental premise of the study is that high levels of aerodynamic performance for flap systems can be achieved only if the flow about the wing remains predominantly attached. Based on this premise, a wing design program is used to provide idealized attached flow camber surfaces from which candidate flap systems may be derived, and, in a following step, a wing evaluation program is used to provide estimates of the aerodynamic performance of the candidate systems. Design strategies and techniques that may be employed are illustrated through a series of examples. Applicability of the numerical methods to the analysis of a representative flap system (although not a system designed by the process described here) is demonstrated in a comparison with experimental data.

  6. Computer-aided design and manufacturing and rapid prototyped nanoscale hydroxyapatite/polyamide (n-HA/PA) construction for condylar defect caused by mandibular angle ostectomy.

    PubMed

    Li, Jihua; Hsu, Yuchun; Luo, En; Khadka, Ashish; Hu, Jing

    2011-08-01

    The fracture or defect of the mandibular condyle is one of the serious complications during angle-reduction ostectomy. Reconstruction of such defects also is a daunting task. The case report describes a method based on computer-aided design/computer-aided manufacturing (CAD/CAM) and rapid prototyping nanoscale hydroxyapatite/polyamide (n-HA/PA) for individual design, fabrication, and implantation of a mandibular condyle. A 27-year-old woman with a square-shaped face who had previously undergone mandibular angle reduction reported with malocclusion, deviated mouth, collapse of the right side of the face, and masticatory problems. The reason for the problems was the unintended removal of the condyle during the ostectomy procedure. Using computed tomography (CT) data, a biomimetic n-HA/PA scaffold, and CAD/CAM for rapid prototyping by three-dimensional (3D) printing, a perfect-fitting condylar implant was fabricated. A surgical guide system also was developed to reproduce the procedures accurately so a perfect fit could be obtained during surgery. The patient ultimately regained reasonable jaw contour and appearance, as well as appreciable temporomandibular joint (TMJ) function.

  7. WINCADRE INORGANIC (WINDOWS COMPUTER-AIDED DATA REVIEW AND EVALUATION)

    EPA Science Inventory

    WinCADRE (Computer-Aided Data Review and Evaluation) is a Windows -based program designed for computer-assisted data validation. WinCADRE is a powerful tool which significantly decreases data validation turnaround time. The electronic-data-deliverable format has been designed in...

  8. WINCADRE (COMPUTER-AIDED DATA REVIEW AND EVALUATION)

    EPA Science Inventory

    WinCADRE (Computer-Aided Data Review and Evaluation) is a Windows -based program designed for computer-assisted data validation. WinCADRE is a powerful tool which significantly decreases data validation turnaround time. The electronic-data-deliverable format has been designed ...

  9. Computer-aided resection and endoprosthesis design for the management of malignant bone tumors around the knee: outcomes of 12 cases

    PubMed Central

    2013-01-01

    Background To report the outcomes of computer-aided resection and endoprosthesis design for the management of malignant bone tumors around the knee. Methods Computed tomography (CT) and magnetic resonance imaging (MRI) data were input into computer software to produce three-dimensional (3D) models of the tumor extent. Imaging data was then used to create a template for surgical resection, and development of an individualized combined allogeneic bone/endoprosthesis. Surgical simulations were performed prior to the actual surgery. Results This study included 9 males and 3 females with a mean age of 25.3 years (range, 13 to 40 years). There were 9 tumors in the distal femur and 3 in the proximal tibia. There were no surgical complications. In all cases pathologically confirmed clear surgical margins were obtained. Postoperative radiographs showed the range of tumor resection was in accordance with the preoperative design, and the morphological reconstruction of the bone defect was satisfactory with complete bilateral symmetry. The mean follow-up time was 26.5 months. Two patients died of their disease and the remaining are alive and well without evidence of recurrence. All patients are able to ambulate freely without restrictions. At the last follow-up, the average International Society of Limb Salvage score was 25.8 (range, 18 to 27), and was excellent in 8 cases and good in 4 cases. Conclusions Computer-aided design and modeling for the surgical management of bone tumors and subsequent limb reconstruction provides accurate tumor removal with the salvage of a maximal amount of unaffected bone and precise endoprosthesis reconstruction. PMID:24267157

  10. Enhanced Thermostability of Lipoxygenase from Anabaena sp. PCC 7120 by Site-Directed Mutagenesis Based on Computer-Aided Rational Design.

    PubMed

    Diao, Hanwen; Zhang, Chong; Wang, Shuicheng; Lu, Fengxia; Lu, Zhaoxin

    2016-04-01

    Lipoxygenase from Anabaena sp. PCC 7120 (Ana-LOX) was thermally unstable. So, improving the thermostability of the enzyme was quite essential. The target site of Ana-LOX selected for site-directed mutagenesis was based on computer-aided rational design. The thermostability and specific activity of Ana-LOX were improved with replacing valine with alanine at the target site 421 and the site 40. Compared to the wild-type enzyme which has a half-life (T 1/2) of inactivation of 3.8 min at 50 °C, the T 1/2 of mutant enzymes with V421A and V40A substitution increased to 4.4 and 7.0 min, respectively. The double mutant V421A/V40A showed a synergistic effect with a T 1/2 value of 8.3 min, resulting in a 1.18-fold improvement compared to the original Ana-LOX. V421A, V40A, and V421A/V40A also obtained 4.83, 41.58, and 80.07 % increase in specific activity, respectively. This study provides useful theoretical reference for enzyme molecular modification and computer-aided rational design.

  11. Prerequisites for Computer-Aided Cognitive Rehabilitation.

    ERIC Educational Resources Information Center

    Legrand, Colette

    1989-01-01

    This paper describes computer-aided cognitive rehabilitation for mentally deficient persons. It lists motor, cognitive, emotional, and educational prerequisites to such rehabilitation and states advantages and disadvantages in using the prerequisites. (JDD)

  12. Computer-aided design of liposomal drugs: In silico prediction and experimental validation of drug candidates for liposomal remote loading.

    PubMed

    Cern, Ahuva; Barenholz, Yechezkel; Tropsha, Alexander; Goldblum, Amiram

    2014-01-10

    Previously we have developed and statistically validated Quantitative Structure Property Relationship (QSPR) models that correlate drugs' structural, physical and chemical properties as well as experimental conditions with the relative efficiency of remote loading of drugs into liposomes (Cern et al., J. Control. Release 160 (2012) 147-157). Herein, these models have been used to virtually screen a large drug database to identify novel candidate molecules for liposomal drug delivery. Computational hits were considered for experimental validation based on their predicted remote loading efficiency as well as additional considerations such as availability, recommended dose and relevance to the disease. Three compounds were selected for experimental testing which were confirmed to be correctly classified by our previously reported QSPR models developed with Iterative Stochastic Elimination (ISE) and k-Nearest Neighbors (kNN) approaches. In addition, 10 new molecules with known liposome remote loading efficiency that were not used by us in QSPR model development were identified in the published literature and employed as an additional model validation set. The external accuracy of the models was found to be as high as 82% or 92%, depending on the model. This study presents the first successful application of QSPR models for the computer-model-driven design of liposomal drugs.

  13. Computer-aided design of liposomal drugs: in silico prediction and experimental validation of drug candidates for liposomal remote loading

    PubMed Central

    Cern, Ahuva; Barenholz, Yechezkel; Tropsha, Alexander; Goldblum, Amiram

    2014-01-01

    Previously we have developed and statistically validated Quantitative Structure Property Relationship (QSPR) models that correlate drugs’ structural, physical and chemical properties as well as experimental conditions with the relative efficiency of remote loading of drugs into liposomes (Cern et al, Journal of Controlled Release, 160(2012) 14–157). Herein, these models have been used to virtually screen a large drug database to identify novel candidate molecules for liposomal drug delivery. Computational hits were considered for experimental validation based on their predicted remote loading efficiency as well as additional considerations such as availability, recommended dose and relevance to the disease. Three compounds were selected for experimental testing which were confirmed to be correctly classified by our previously reported QSPR models developed with Iterative Stochastic Elimination (ISE) and k-nearest neighbors (kNN) approaches. In addition, 10 new molecules with known liposome remote loading efficiency that were not used in QSPR model development were identified in the published literature and employed as an additional model validation set. The external accuracy of the models was found to be as high as 82% or 92%, depending on the model. This study presents the first successful application of QSPR models for the computer-model-driven design of liposomal drugs. PMID:24184343

  14. Quality indexing with computer-aided lexicography

    NASA Technical Reports Server (NTRS)

    Buchan, Ronald L.

    1992-01-01

    Indexing with computers is a far cry from indexing with the first indexing tool, the manual card sorter. With the aid of computer-aided lexicography, both indexing and indexing tools can provide standardization, consistency, and accuracy, resulting in greater quality control than ever before. A brief survey of computer activity in indexing is presented with detailed illustrations from NASA activity. Applications from techniques mentioned, such as Retrospective Indexing (RI), can be made to many indexing systems. In addition to improving the quality of indexing with computers, the improved efficiency with which certain tasks can be done is demonstrated.

  15. Intelligent computer-aided training authoring environment

    NASA Technical Reports Server (NTRS)

    Way, Robert D.

    1994-01-01

    Although there has been much research into intelligent tutoring systems (ITS), there are few authoring systems available that support ITS metaphors. Instructional developers are generally obliged to use tools designed for creating on-line books. We are currently developing an authoring environment derived from NASA's research on intelligent computer-aided training (ICAT). The ICAT metaphor, currently in use at NASA has proven effective in disciplines from satellite deployment to high school physics. This technique provides a personal trainer (PT) who instructs the student using a simulated work environment (SWE). The PT acts as a tutor, providing individualized instruction and assistance to each student. Teaching in an SWE allows the student to learn tasks by doing them, rather than by reading about them. This authoring environment will expedite ICAT development by providing a tool set that guides the trainer modeling process. Additionally, this environment provides a vehicle for distributing NASA's ICAT technology to the private sector.

  16. In vivo MRI-Based 3D FSI RV/LV Models for Human Right Ventricle and Patch Design for Potential Computer-Aided Surgery Optimization.

    PubMed

    Yang, Chun; Tang, Dalin; Haber, Idith; Geva, Tal; Del Nido, Pedro J

    2007-01-01

    Right ventricular dysfunction is one of the more common causes of heart failure in patients with congenital heart defects. Use of computer-assisted procedures is becoming more popular in clinical decision making process and computer-aided surgeries. A 3D in vivo MRI-based RV/LV combination model with fluid-structure interaction (FSI), RV-LV interaction, and RV-patch interaction was introduced to perform mechanical analysis for human right ventricle with potential clinical applications. Patient-specific RV/LV morphologies were acquired by using planar tagged MRI. The 3D RV/LV FSI model was solved using a commercial finite element package ADINA. Our results indicated that flow and stress/strain distributions in the right ventricle are closely related to RV morphology, material properties and blood pressure conditions. Patches with material properties better matching RV tissue properties and smaller size lead to better RV function recoveries. Computational RV volumes showed very good agreement with MRI data (error < 3%). More patient studies are needed to establish baseline database so that computational simulations can be used to replace empirical and often risky clinical experimentation to examine the efficiency and suitability of various reconstructive procedures in diseased hearts and optimal design can be found.

  17. Rapid Computer Aided Ligand Design and Screening of Precious Metal Extractants from TRUEX Raffinate with Experimental Validation

    SciTech Connect

    Clark, Aurora Sue; Wall, Nathalie; Benny, Paul

    2015-11-16

    through the design of a software program that uses state-of-the-art computational combinatorial chemistry, and is developed and validated with experimental data acquisition; the resulting tool allows for rapid design and screening of new ligands for the extraction of precious metals from SNF. This document describes the software that has been produced, ligands that have been designed, and fundamental new understandings of the extraction process of Rh(III) as a function of solution phase conditions (pH, nature of acid, etc.).

  18. COMPUTER-AIDED DRAFTING AND DESIGN, A THREE-WEEK SUMMER INSTITUTE TRAINING PROGRAM (MIAMI-DADE JUNIOR COLLEGE, MIAMI, FLORIDA, JULY 10, 1967 - JULY 28, 1967). FINAL REPORT.

    ERIC Educational Resources Information Center

    MORPHONIOS, ALEX G.

    THIRTY-SIX INSTRUCTORS, SUPERVISORS, AND DEPARTMENT CHAIRMEN IN AREAS OF DRAFTING, ENGINEERING, MANUFACTURING, AND COMPUTER TECHNOLOGY AT JUNIOR COLLEGES, TECHNICAL, AND AREA VOCATIONAL SCHOOLS IN 20 STATES ATTENDED A 3-WEEK SUMMER INSTITUTE TRAINING PROGRAM ON COMPUTER-AIDED DRAFTING AND DESIGN. EXPERIENCE IN PROGRAMING THE IBM SYSTEM 1620 WITH…

  19. The polar phase response property of monopolar ECG voltages using a Computer-Aided Design and Drafting (CAD)-based data acquisition system.

    PubMed

    Goswami, B; Mitra, M; Nag, B; Mitra, T K

    1993-11-01

    The present paper discusses a Computer-Aided Design and Drafting (CAD) based data acquisition and polar phase response study of the ECG. The scalar ECG does not show vector properties although such properties are embedded in it. In the present paper the polar phase response property of monopolar chest lead (V1 to V6) ECG voltages has been studied. A software tool has been used to evaluate the relative phase response of ECG voltages. The data acquisition of monopolar ECG records of chest leads V1 to V6 from the chart recorder has been done with the help of the AutoCAD application package. The spin harmonic constituents of ECG voltages are evaluated at each harmonic plane and the polar phase responses are studied at each plane. Some interesting results have been observed in some typical cases which are discussed in the paper. PMID:8307653

  20. Computer-aided design of nanostructures from self- and directed-assembly of soft matter building blocks

    NASA Astrophysics Data System (ADS)

    Nguyen, Trung Dac

    2011-12-01

    Functional materials that are active at nanometer scales and adaptive to environment have been highly desirable for a huge array of novel applications ranging from photonics, sensing, fuel cells, smart materials to drug delivery and miniature robots. These bio-inspired features imply that the underlying structure of this type of materials should possess a well-defined ordering as well as the ability to reconfigure in response to a given external stimulus such as temperature, electric field, pH or light. In this thesis, we employ computer simulation as a design tool, demonstrating that various ordered and reconfigurable structures can be obtained from the self- and directed-assembly of soft matter nano-building blocks such as nanoparticles, polymer-tethered nanoparticles and colloidal particles. We show that, besides thermodynamic parameters, the self-assembly of these building blocks is governed by nanoparticle geometry, the number and attachment location of tethers, solvent selectivity, balance between attractive and repulsive forces, nanoparticle size polydispersity, and field strength. We demonstrate that higher-order nanostructures, i.e. those for which the correlation length is much greater than the length scale of individual assembling building blocks, can be hierarchically assembled. For instance, bilayer sheets formed by laterally tethered rods fold into spiral scrolls and helical structures, which are able to adopt different morphologies depending on the environmental condition. We find that a square grid structure formed by laterally tethered nanorods can be transformed into a bilayer sheet structure, and vice versa, upon shortening, or lengthening, the rod segments, respectively. From these inspiring results, we propose a general scheme by which shape-shifting particles are employed to induce the reconfiguration of pre-assembled structures. Finally, we investigate the role of an external field in assisting the formation of assembled structures that would

  1. A Computational Method Designed to Aid in the Teaching of Copolymer Composition and Microstructure as a Function of Conversion.

    ERIC Educational Resources Information Center

    Coleman, M. M.; Varnell, W. D.

    1982-01-01

    Describes a computer program (FORTRAN and APPLESOFT) demonstrating the effect of copolymer composition as a function of conversion, providing theoretical background and examples of types of information gained from computer calculations. Suggests that the program enhances undergraduate students' understanding of basic copolymerization theory.…

  2. Aids to School Bus Design

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Navistar International Transportation Corporation, Chicago, IL, used three separate NASA-developed technologies in the design and testing of their 3000 Series Bus Chassis which was developed expressly for school bus applications. For structural analysis, they used the MSC/NASTRAN program which mathematically analyzes a design and predicts how it will hold up under stress. They also used the SPATE 9000 system for non-contact measurement of stress, load transfer mechanisms, detection of hidden flaws, and monitoring structural changes during fatigue testing. SPATE 9000 was based on infrared stress measurement technology developed by Langley Research Center. They also employed the Wyle Ride Quality Meter, which was developed by Langley to aid in passenger aircraft design by providing an accurate measurement of ride vibration and sound level. These numbers translate into a subjective discomfort level index. These technologies contribute to the company's 45-48 percent share of the school bus chassis market.

  3. Research related to improved computer aided design software package. [comparative efficiency of finite, boundary, and hybrid element methods in elastostatics

    NASA Technical Reports Server (NTRS)

    Walston, W. H., Jr.

    1986-01-01

    The comparative computational efficiencies of the finite element (FEM), boundary element (BEM), and hybrid boundary element-finite element (HVFEM) analysis techniques are evaluated for representative bounded domain interior and unbounded domain exterior problems in elastostatics. Computational efficiency is carefully defined in this study as the computer time required to attain a specified level of solution accuracy. The study found the FEM superior to the BEM for the interior problem, while the reverse was true for the exterior problem. The hybrid analysis technique was found to be comparable or superior to both the FEM and BEM for both the interior and exterior problems.

  4. Computer-aided vaccine designing approach against fish pathogens Edwardsiella tarda and Flavobacterium columnare using bioinformatics softwares

    PubMed Central

    Mahendran, Radha; Jeyabaskar, Suganya; Sitharaman, Gayathri; Michael, Rajamani Dinakaran; Paul, Agnal Vincent

    2016-01-01

    Edwardsiella tarda and Flavobacterium columnare are two important intracellular pathogenic bacteria that cause the infectious diseases edwardsiellosis and columnaris in wild and cultured fish. Prediction of major histocompatibility complex (MHC) binding is an important issue in T-cell epitope prediction. In a healthy immune system, the T-cells must recognize epitopes and induce the immune response. In this study, T-cell epitopes were predicted by using in silico immunoinformatics approach with the help of bioinformatics tools that are less expensive and are not time consuming. Such identification of binding interaction between peptides and MHC alleles aids in the discovery of new peptide vaccines. We have reported the potential peptides chosen from the outer membrane proteins (OMPs) of E. tarda and F. columnare, which interact well with MHC class I alleles. OMPs from E. tarda and F. columnare were selected and analyzed based on their antigenic and immunogenic properties. The OMPs of the genes TolC and FCOL_04620, respectively, from E. tarda and F. columnare were taken for study. Finally, two epitopes from the OMP of E. tarda exhibited excellent protein–peptide interaction when docked with MHC class I alleles. Five epitopes from the OMP of F. columnare had good protein–peptide interaction when docked with MHC class I alleles. Further in vitro studies can aid in the development of potential peptide vaccines using the predicted peptides. PMID:27284239

  5. Computer-aided vaccine designing approach against fish pathogens Edwardsiella tarda and Flavobacterium columnare using bioinformatics softwares.

    PubMed

    Mahendran, Radha; Jeyabaskar, Suganya; Sitharaman, Gayathri; Michael, Rajamani Dinakaran; Paul, Agnal Vincent

    2016-01-01

    Edwardsiella tarda and Flavobacterium columnare are two important intracellular pathogenic bacteria that cause the infectious diseases edwardsiellosis and columnaris in wild and cultured fish. Prediction of major histocompatibility complex (MHC) binding is an important issue in T-cell epitope prediction. In a healthy immune system, the T-cells must recognize epitopes and induce the immune response. In this study, T-cell epitopes were predicted by using in silico immunoinformatics approach with the help of bioinformatics tools that are less expensive and are not time consuming. Such identification of binding interaction between peptides and MHC alleles aids in the discovery of new peptide vaccines. We have reported the potential peptides chosen from the outer membrane proteins (OMPs) of E. tarda and F. columnare, which interact well with MHC class I alleles. OMPs from E. tarda and F. columnare were selected and analyzed based on their antigenic and immunogenic properties. The OMPs of the genes TolC and FCOL_04620, respectively, from E. tarda and F. columnare were taken for study. Finally, two epitopes from the OMP of E. tarda exhibited excellent protein-peptide interaction when docked with MHC class I alleles. Five epitopes from the OMP of F. columnare had good protein-peptide interaction when docked with MHC class I alleles. Further in vitro studies can aid in the development of potential peptide vaccines using the predicted peptides. PMID:27284239

  6. Design analysis and computer-aided performance evaluation of shuttle orbiter electrical power system. Volume 2: SYSTID user's guide

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The manual for the use of the computer program SYSTID under the Univac operating system is presented. The computer program is used in the simulation and evaluation of the space shuttle orbiter electric power supply. The models described in the handbook are those which were available in the original versions of SYSTID. The subjects discussed are: (1) program description, (2) input language, (3) node typing, (4) problem submission, and (5) basic and power system SYSTID libraries.

  7. Mathematical modelling in the computer-aided process planning

    NASA Astrophysics Data System (ADS)

    Mitin, S.; Bochkarev, P.

    2016-04-01

    This paper presents new approaches to organization of manufacturing preparation and mathematical models related to development of the computer-aided multi product process planning (CAMPP) system. CAMPP system has some peculiarities compared to the existing computer-aided process planning (CAPP) systems: fully formalized developing of the machining operations; a capacity to create and to formalize the interrelationships among design, process planning and process implementation; procedures for consideration of the real manufacturing conditions. The paper describes the structure of the CAMPP system and shows the mathematical models and methods to formalize the design procedures.

  8. Novel Ergonomic Postural Assessment Method (NERPA) Using Product-Process Computer Aided Engineering for Ergonomic Workplace Design

    PubMed Central

    Sanchez-Lite, Alberto; Garcia, Manuel; Domingo, Rosario; Angel Sebastian, Miguel

    2013-01-01

    Background Musculoskeletal disorders (MSDs) that result from poor ergonomic design are one of the occupational disorders of greatest concern in the industrial sector. A key advantage in the primary design phase is to focus on a method of assessment that detects and evaluates the potential risks experienced by the operative when faced with these types of physical injuries. The method of assessment will improve the process design identifying potential ergonomic improvements from various design alternatives or activities undertaken as part of the cycle of continuous improvement throughout the differing phases of the product life cycle. Methodology/Principal Findings This paper presents a novel postural assessment method (NERPA) fit for product-process design, which was developed with the help of a digital human model together with a 3D CAD tool, which is widely used in the aeronautic and automotive industries. The power of 3D visualization and the possibility of studying the actual assembly sequence in a virtual environment can allow the functional performance of the parts to be addressed. Such tools can also provide us with an ergonomic workstation design, together with a competitive advantage in the assembly process. Conclusions The method developed was used in the design of six production lines, studying 240 manual assembly operations and improving 21 of them. This study demonstrated the proposed method’s usefulness and found statistically significant differences in the evaluations of the proposed method and the widely used Rapid Upper Limb Assessment (RULA) method. PMID:23977340

  9. The Old Paradigm in Computer Aids to Invention: A Critical Review.

    ERIC Educational Resources Information Center

    Langston, M. Diane

    1986-01-01

    Reviews the major types of computer aids to invention to reveal the paper-based design paradigm that characterizes them. Discusses implications of this "old paradigm" and suggests directions for developing new, uniquely electronic paradigms for future aids. (AEW)

  10. Updates on the Construction of an Eyeglass-Supported Nasal Prosthesis Using Computer-Aided Design and Rapid Prototyping Technology.

    PubMed

    Ciocca, Leonardo; Tarsitano, Achille; Marchetti, Claudio; Scotti, Roberto

    2016-01-01

    This study was undertaken to design an updated connection system for an eyeglass-supported nasal prosthesis using rapid prototyping techniques. The substructure was developed with two main endpoints in mind: the connection to the silicone and the connection to the eyeglasses. The mold design was also updated; the mold was composed of various parts, each carefully designed to allow for easy release after silicone processing and to facilitate extraction of the prosthesis without any strain. The approach used in this study enabled perfect transfer of the reciprocal position of the prosthesis with respect to the eyeglasses, from the virtual to the clinical environment. Moreover, the reduction in thickness improved the flexibility of the prosthesis and promoted adaptation to the contours of the skin, even during functional movements. The method described here is a simplified and viable alternative to standard construction techniques for nasal prostheses and offers improved esthetic and functional results when no bone is available for implant-supported prostheses.

  11. Exploratory research for the development of a computer aided software design environment with the software technology program

    NASA Technical Reports Server (NTRS)

    Hardwick, Charles

    1991-01-01

    Field studies were conducted by MCC to determine areas of research of mutual interest to MCC and JSC. NASA personnel from the Information Systems Directorate and research faculty from UHCL/RICIS visited MCC in Austin, Texas to examine tools and applications under development in the MCC Software Technology Program. MCC personnel presented workshops in hypermedia, design knowledge capture, and design recovery on site at JSC for ISD personnel. The following programs were installed on workstations in the Software Technology Lab, NASA/JSC: (1) GERM (Graphic Entity Relations Modeler); (2) gIBIS (Graphic Issues Based Information System); and (3) DESIRE (Design Recovery tool). These applications were made available to NASA for inspection and evaluation. Programs developed in the MCC Software Technology Program run on the SUN workstation. The programs do not require special configuration, but they will require larger than usual amounts of disk space and RAM to operate properly.

  12. Continuity of computer-aided drafting operations

    SciTech Connect

    Jacobson, L.D.

    1987-09-01

    The operating performance, operating procedures, and equipment added are discussed for the Computer Aided Drafting (CAD) operation at UNC Nuclear Industries before consolidation of operating contracts at the US Department of Energy (DOE) facilities located at the Hanford Site, near Richland, Washington.

  13. Computer-Aided Corrosion Program Management

    NASA Technical Reports Server (NTRS)

    MacDowell, Louis

    2010-01-01

    This viewgraph presentation reviews Computer-Aided Corrosion Program Management at John F. Kennedy Space Center. The contents include: 1) Corrosion at the Kennedy Space Center (KSC); 2) Requirements and Objectives; 3) Program Description, Background and History; 4) Approach and Implementation; 5) Challenges; 6) Lessons Learned; 7) Successes and Benefits; and 8) Summary and Conclusions.

  14. Experiments in Computer-Aided Inductive Reasoning.

    ERIC Educational Resources Information Center

    Newman, J.R.; Rogers, M.S.

    This research is concerned with human problem-solving behavior that involves inductive reasoning or concept formation when that behavior is being assisted by certain computer and display aids (called symbol manipulation functions). Human subjects use a variety of systematic operations when they are solving such problems. In order to analyze…

  15. Design analysis and computer-aided performance evaluation of shuttle orbiter electrical power system. Volume 1: Summary

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Studies were conducted to develop appropriate space shuttle electrical power distribution and control (EPDC) subsystem simulation models and to apply the computer simulations to systems analysis of the EPDC. A previously developed software program (SYSTID) was adapted for this purpose. The following objectives were attained: (1) significant enhancement of the SYSTID time domain simulation software, (2) generation of functionally useful shuttle EPDC element models, and (3) illustrative simulation results in the analysis of EPDC performance, under the conditions of fault, current pulse injection due to lightning, and circuit protection sizing and reaction times.

  16. Solving rational matrix equations in the state space with applications to computer-aided control-system design

    NASA Technical Reports Server (NTRS)

    Packard, A. K.; Sastry, S. S.

    1986-01-01

    A method of solving a class of linear matrix equations over various rings is proposed, using results from linear geometric control theory. An algorithm, successfully implemented, is presented, along with non-trivial numerical examples. Applications of the method to the algebraic control system design methodology are discussed.

  17. Fragment-based docking: development of the CHARMMing Web user interface as a platform for computer-aided drug design.

    PubMed

    Pevzner, Yuri; Frugier, Emilie; Schalk, Vinushka; Caflisch, Amedeo; Woodcock, H Lee

    2014-09-22

    Web-based user interfaces to scientific applications are important tools that allow researchers to utilize a broad range of software packages with just an Internet connection and a browser. One such interface, CHARMMing (CHARMM interface and graphics), facilitates access to the powerful and widely used molecular software package CHARMM. CHARMMing incorporates tasks such as molecular structure analysis, dynamics, multiscale modeling, and other techniques commonly used by computational life scientists. We have extended CHARMMing's capabilities to include a fragment-based docking protocol that allows users to perform molecular docking and virtual screening calculations either directly via the CHARMMing Web server or on computing resources using the self-contained job scripts generated via the Web interface. The docking protocol was evaluated by performing a series of "re-dockings" with direct comparison to top commercial docking software. Results of this evaluation showed that CHARMMing's docking implementation is comparable to many widely used software packages and validates the use of the new CHARMM generalized force field for docking and virtual screening.

  18. Fragment-Based Docking: Development of the CHARMMing Web User Interface as a Platform for Computer-Aided Drug Design

    PubMed Central

    2015-01-01

    Web-based user interfaces to scientific applications are important tools that allow researchers to utilize a broad range of software packages with just an Internet connection and a browser.1 One such interface, CHARMMing (CHARMM interface and graphics), facilitates access to the powerful and widely used molecular software package CHARMM. CHARMMing incorporates tasks such as molecular structure analysis, dynamics, multiscale modeling, and other techniques commonly used by computational life scientists. We have extended CHARMMing’s capabilities to include a fragment-based docking protocol that allows users to perform molecular docking and virtual screening calculations either directly via the CHARMMing Web server or on computing resources using the self-contained job scripts generated via the Web interface. The docking protocol was evaluated by performing a series of “re-dockings” with direct comparison to top commercial docking software. Results of this evaluation showed that CHARMMing’s docking implementation is comparable to many widely used software packages and validates the use of the new CHARMM generalized force field for docking and virtual screening. PMID:25151852

  19. Aspects on Transfer of Aided - Design Files

    NASA Astrophysics Data System (ADS)

    Goanta, A. M.; Anghelache, D. G.

    2016-08-01

    At this stage of development of hardware and software, each company that makes design software packages has a certain type of file created and customized in time to distinguish that company from its competitors. Thus today are widely known the DWG files belonging AutoCAD, IPT / IAM belonging to Inventor, PAR / ASM of Solid Edge's, PRT from the NX and so on. Behind every type of file there is a mathematical model which is common to more types of files. A specific aspect of the computer -aided design is that all softwares are working with both individual parts and assemblies, but their approach is different in that some use the same type of file both for each part and for the whole (PRT ), while others use different types of files (IPT / IAM, PAR / ASM, etc.). Another aspect of the computer -aided design is to transfer files between different companies which use different software packages or even the same software package but in different versions. Each of these situations generates distinct issues. Thus, to solve the partial reading by a project different from the native one, transfer files of STEP and IGES type are used

  20. Information and computer-aided system for structural materials

    NASA Astrophysics Data System (ADS)

    Nekrashevitch, Ju. G.; Nizametdinov, Sh. U.; Polkovnikov, A. V.; Rumjantzev, V. P.; Surina, O. N.; Kalinin, G. M.; Sidorenkov, A. V.; Strebkov, Ju. S.

    1992-09-01

    An information and computer-aided system for structural materials data has been developed to provide data for the fusion and fission reactor system design. It is designed for designers, industrial engineers, and material science specialists and provides a friendly interface in an interactive mode. The database for structural materials contains the master files: chemical composition, physical, mechanical, corrosion, technological properties, regulatory and technical documentation. The system is implemented on a PC/AT running the PS/2 operating system.

  1. SADIST (the SAndia Data Index STructure): a stand-alone data base for computer-aided design and general use

    SciTech Connect

    Stauffer, J D

    1980-11-01

    A file structure has been designed that fills the needs of multilevel hierarchical design of integrated circuits (ICs). Since the structure is actualized by a stand-alone FORTRAN program, it is applicable to general-purpose use in situations where the structure of the data modeled is similar to that of IC data. Though the structure itself is a FORTRAN direct-access file, its interface with user programs is a small sequential subfile accessible to FORTRAN, PASCAL, and most other languages. This ability facilitates linkup to systems already in use and requires minimal recoding. Backup, restore, and other data base recovery and integrity operations are automatic, but may be initiated by the user if desired. 3 figures.

  2. 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.

  3. How Effective Is Feedback in Computer-Aided Assessments?

    ERIC Educational Resources Information Center

    Gill, Mundeep; Greenhow, Martin

    2008-01-01

    Computer-Aided Assessments (CAAs) have been used increasingly at Brunel University for over 10 years to test students' mathematical abilities. Recently, we have focussed on providing very rich feedback to the students; given the work involved in designing and coding such feedback, it is important to study the impact of the interaction between…

  4. The complement regulator C4b-binding protein analyzed by molecular modeling, bioinformatics and computer-aided experimental design.

    PubMed

    Villoutreix, B O; Blom, A M; Webb, J; Dahlbäck, B

    1999-05-01

    Molecular modeling and bioinformatics have gained recognition as scientific disciplines of importance in the field of biomedical research. Molecular modeling not only allows to predict the three-dimensional structure of a protein but also helps to define its function. Careful incorporation of the experimental findings in the structural/theoretical data provides means to understand molecular mechanisms for highly complex biological systems. C4b-binding protein (C4BP) is composed of one beta-chain and seven alpha-chains essentially built from three- and eight-complement control protein (CCP) modules, respectively, followed by a non-repeat carboxy-terminal region involved in polymerization of the chains. C4BP is involved in the regulation of the complement system and interacts with many molecules such as C4b, Arp, protein S and heparin. Here, we report experimental and computer data obtained for C4BP. Protein modeling together with site directed mutagenesis indicate that R39, R64 and R66 from the C4BP alpha-chain form a key binding site for heparin, suggesting that this region could be of major importance for interaction with C4b. We also propose that the first CCP of the C4BP beta-chain displays a key hydrophobic surface of major importance for the interaction with the coagulation cofactor protein S. PMID:10408373

  5. Fragment-based approaches and computer-aided drug discovery.

    PubMed

    Rognan, Didier

    2012-01-01

    Fragment-based design has significantly modified drug discovery strategies and paradigms in the last decade. Besides technological advances and novel therapeutic avenues, one of the most significant changes brought by this new discipline has occurred in the minds of drug designers. Fragment-based approaches have markedly impacted rational computer-aided design both in method development and in applications. The present review illustrates the importance of molecular fragments in many aspects of rational ligand design, and discusses how thinking in "fragment space" has boosted computational biology and chemistry. PMID:21710380

  6. Computer-aided diagnosis in thoracic CT

    NASA Astrophysics Data System (ADS)

    Li, Qiang

    2009-10-01

    Computer-aided diagnosis (CAD) provides a computer output as a "second opinion" in order to assist radiologists in the diagnosis of various diseases on medical images. Currently, a hot topic in CAD is the development of computerized schemes for detection of lung abnormalities, such as lung nodule and interstitial lung disease, in computed tomography (CT) images. The author describes in this article the current status of the CAD schemes for the detection of lung nodules and interstitial lung disease in CT developed by the author and his colleagues at the University of Chicago and Duke University.

  7. Recoding of the Vesicular Stomatitis Virus L Gene by Computer-Aided Design Provides a Live, Attenuated Vaccine Candidate

    PubMed Central

    Wang, Bingyin; Yang, Chen; Tekes, Gergely; Mueller, Steffen; Paul, Aniko; Whelan, Sean P. J.

    2015-01-01

    ABSTRACT Codon pair bias (CPB), which has been observed in all organisms, is a neglected genomic phenomenon that affects gene expression. CPB results from synonymous codons that are paired more or less frequently in ORFeomes regardless of codon bias. The effect of an individual codon pair change is usually small, but when it is amplified by large-scale genome recoding, strikingly altered biological phenotypes are observed. The utility of codon pair bias in the development of live attenuated vaccines was recently demonstrated by recodings of poliovirus (a positive-strand RNA virus) and influenza virus (a negative-strand segmented RNA virus). Here, the L gene of vesicular stomatitis virus (VSV), a nonsegmented negative-sense RNA virus, was partially recoded based on codon pair bias. Totals of 858 and 623 silent mutations were introduced into a 5′-terminal segment of the viral L gene (designated L1) to create sequences containing either overrepresented or underrepresented codon pairs, designated L1sdmax and L1min, respectively. Analysis revealed that recombinant VSV containing the L1min sequence could not be recovered, whereas the virus with the sdmax sequence showed a modest level of attenuation in cell culture. More strikingly, in mice the L1sdmax virus was almost as immunogenic as the parental strain but highly attenuated. Taken together, these results open a new road to attain a balance between VSV virulence and immunogenicity, which could serve as an example for the attenuation of other negative-strand, nonsegmented RNA viruses. PMID:25827413

  8. Intelligent computer-aided training and tutoring

    NASA Technical Reports Server (NTRS)

    Loftin, R. Bowen; Savely, Robert T.

    1991-01-01

    Specific autonomous training systems based on artificial intelligence technology for use by NASA astronauts, flight controllers, and ground-based support personnel that demonstrate an alternative to current training systems are described. In addition to these specific systems, the evolution of a general architecture for autonomous intelligent training systems that integrates many of the features of traditional training programs with artificial intelligence techniques is presented. These Intelligent Computer-Aided Training (ICAT) systems would provide, for the trainee, much of the same experience that could be gained from the best on-the-job training. By integrating domain expertise with a knowledge of appropriate training methods, an ICAT session should duplicate, as closely as possible, the trainee undergoing on-the-job training in the task environment, benefitting from the full attention of a task expert who is also an expert trainer. Thus, the philosophy of the ICAT system is to emulate the behavior of an experienced individual devoting his full time and attention to the training of a novice - proposing challenging training scenarios, monitoring and evaluating the actions of the trainee, providing meaningful comments in response to trainee errors, responding to trainee requests for information, giving hints (if appropriate), and remembering the strengths and weaknesses displayed by the trainee so that appropriate future exercises can be designed.

  9. Computer-aided diagnosis (CAD) for colonoscopy

    NASA Astrophysics Data System (ADS)

    Gu, Jia; Poirson, Allen

    2007-03-01

    Colorectal cancer is the second leading cause of cancer deaths, and ranks third for new cancer cases and cancer mortality for both men and women. However, its death rate can be dramatically reduced by appropriate treatment when early detection is available. The purpose of colonoscopy is to identify and assess the severity of lesions, which may be flat or protruding. Due to the subjective nature of the examination, colonoscopic proficiency is highly variable and dependent upon the colonoscopist's knowledge and experience. An automated image processing system providing an objective, rapid, and inexpensive analysis of video from a standard colonoscope could provide a valuable tool for screening and diagnosis. In this paper, we present the design, functionality and preliminary results of its Computer-Aided-Diagnosis (CAD) system for colonoscopy - ColonoCAD TM. ColonoCAD is a complex multi-sensor, multi-data and multi-algorithm image processing system, incorporating data management and visualization, video quality assessment and enhancement, calibration, multiple view based reconstruction, feature extraction and classification. As this is a new field in medical image processing, our hope is that this paper will provide the framework to encourage and facilitate collaboration and discussion between industry, academia, and medical practitioners.

  10. Computer-Aided-Instruction (user/CSO computer security training)

    SciTech Connect

    Twyman, J.A.

    1987-01-01

    This paper discusses a Computer-Aided-Instruction (CAI) course that has been implemented at Rocky Flats. Trying to train 2000 computer users and Computer Security Officers (CSO) has been a real dilemma at Rocky Flats. In order to resolve this problem, our Training Department implemented a CAI training course on Computer Security. Presently, we are training approximately 100 users/CSOs per month, and soon these numbers should increase. The duration of the User course is about an hour and the CSO's is about an hour and a half. CAI is being used on the unclassified VAX computer system in conjunction with IBM PC XTs.

  11. Attitudes of Design Students toward Computer Usage in Design

    ERIC Educational Resources Information Center

    Pektas, Sule Tasli; Erkip, Feyzan

    2006-01-01

    The success of efforts to integrate technology with design education is largely affected by the attitudes of students toward technology. This paper presents the findings of a research on the attitudes of design students toward the use of computers in design and its correlates. Computer Aided Design (CAD) tools are the most widely used computer…

  12. Abelson tyrosine-protein kinase 1 as principal target for drug discovery against leukemias. Role of the current computer-aided drug design methodologies.

    PubMed

    Speck-Planche, Alejandro; Luan, Feng; Cordeiro, M N D S

    2012-01-01

    The discovery of anti-cancer agents is an area which continues in accelerated expansion. Leukemias (Lkms) are among the most investigated cancers due to its high and dominant prevalence in children. Computer-aided drug design (CADD) methodologies have been extremely important for the discovery of potent anti-Lkms agents, providing essential insights about the molecular patterns which could be involved in the appearance and development of anti-Lkms activity. The present review is focused on the role of the current CADD methodologies for the discovery of anti-Lkms agents with strong emphasis on the in silico prediction of inhibitors against the primary protein associated with the appearance of Lkms: Abelson tyrosine-protein kinase 1 (TPK-ABL1). In order to make a contribution to the field, we also developed a unified ligand-based approach by exploring Quantitative-Structure Activity Relationships (QSAR) studies. Here, we focused on the construction of two multi-targets (mt) QSAR models by employing a large and heterogeneous database of compounds. These models exhibited excellent statistical quality and predictive power to classifying more than 92% of inhibitors/ no inhibitors against seven proteins associated with Lkms, in both training and prediction sets. By using our unified ligand-based approach we identified several fragments as responsible for the anti-Lkms activity through inhibition of proteins, and new molecules were suggested as versatile inhibitors of the seven proteins under study.

  13. The effect of benzyl isothiocyanate and its computer-aided design derivants targeting alkylglycerone phosphate synthase on the inhibition of human glioma U87MG cell line.

    PubMed

    Zhu, Yu; Liu, Anmin; Zhang, Xuebin; Qi, Lisha; Zhang, Ling; Xue, Jing; Liu, Yi; Yang, Ping

    2015-05-01

    Benzyl isothiocyanate (BITC) has been shown to have inhibitory potential for human glioma U87MG cells; however, the effect and mechanism were not fully clear. In the present study, we found that BITC could inhibit U87MG cell proliferation, adhesion, invasion, and vasculogenic mimicry (VM) formation potential and induce oxidative stress, apoptosis, and cell cycle arrest. We also found that the expression of proliferation, invasion, VM oxidative stress, apoptosis, and cell cycle-related gene and the activity of tumor-related signaling pathways, including protein kinase C (PKC) ζ and Akt/nuclear factor-kappa B (NF-κB) pathways, were suppressed by BITC treatment. We also explored the anti-tumor potential of BITC in vivo, and we found that BITC also could regulate the expression of tumor-related gene and angiogenesis in nude mice model. Finally, we optimized the BITC construction targeting alkylglycerone phosphate synthase (AGPS) by computer-aided design, and the derivants also showed anti-tumor potential in vitro.

  14. Computer-aided-diagnosis (CAD) for colposcopy

    NASA Astrophysics Data System (ADS)

    Lange, Holger; Ferris, Daron G.

    2005-04-01

    Uterine cervical cancer is the second most common cancer among women worldwide. Colposcopy is a diagnostic method, whereby a physician (colposcopist) visually inspects the lower genital tract (cervix, vulva and vagina), with special emphasis on the subjective appearance of metaplastic epithelium comprising the transformation zone on the cervix. Cervical cancer precursor lesions and invasive cancer exhibit certain distinctly abnormal morphologic features. Lesion characteristics such as margin; color or opacity; blood vessel caliber, intercapillary spacing and distribution; and contour are considered by colposcopists to derive a clinical diagnosis. Clinicians and academia have suggested and shown proof of concept that automated image analysis of cervical imagery can be used for cervical cancer screening and diagnosis, having the potential to have a direct impact on improving women"s health care and reducing associated costs. STI Medical Systems is developing a Computer-Aided-Diagnosis (CAD) system for colposcopy -- ColpoCAD. At the heart of ColpoCAD is a complex multi-sensor, multi-data and multi-feature image analysis system. A functional description is presented of the envisioned ColpoCAD system, broken down into: Modality Data Management System, Image Enhancement, Feature Extraction, Reference Database, and Diagnosis and directed Biopsies. The system design and development process of the image analysis system is outlined. The system design provides a modular and open architecture built on feature based processing. The core feature set includes the visual features used by colposcopists. This feature set can be extended to include new features introduced by new instrument technologies, like fluorescence and impedance, and any other plausible feature that can be extracted from the cervical data. Preliminary results of our research on detecting the three most important features: blood vessel structures, acetowhite regions and lesion margins are shown. As this is a new

  15. Computer aided nonlinear electrical networks analysis

    NASA Technical Reports Server (NTRS)

    Slapnicar, P.

    1977-01-01

    Techniques used in simulating an electrical circuit with nonlinear elements for use in computer-aided circuit analysis programs are described. Elements of the circuit include capacitors, resistors, inductors, transistors, diodes, and voltage and current sources (constant or time varying). Simulation features are discussed for dc, ac, and/or transient circuit analysis. Calculations are based on the model approach of formulating the circuit equations. A particular solution of transient analysis for nonlinear storage elements is described.

  16. Interfacing Computer Aided Parallelization and Performance Analysis

    NASA Technical Reports Server (NTRS)

    Jost, Gabriele; Jin, Haoqiang; Labarta, Jesus; Gimenez, Judit; Biegel, Bryan A. (Technical Monitor)

    2003-01-01

    When porting sequential applications to parallel computer architectures, the program developer will typically go through several cycles of source code optimization and performance analysis. We have started a project to develop an environment where the user can jointly navigate through program structure and performance data information in order to make efficient optimization decisions. In a prototype implementation we have interfaced the CAPO computer aided parallelization tool with the Paraver performance analysis tool. We describe both tools and their interface and give an example for how the interface helps within the program development cycle of a benchmark code.

  17. A Computer Aided Implementation of Precision Teaching.

    ERIC Educational Resources Information Center

    Lyons, Dave

    A computer implementation of precision teaching for severely mentally handicapped students is described. Computer technology reduces staff time during a typical precision teaching routine: design of suitable teaching programs, a series of timed short drills using these programs, conversion of results into numeric quantities, and design of improved…

  18. Using the Computer in Systems Engineering Design

    ERIC Educational Resources Information Center

    Schmidt, W.

    1970-01-01

    With the aid of the programmed computer, the systems designer can analyze systems for which certain components have not yet been manufactured or even invented, and the power of solution-technique is greatly increased. (IR)

  19. Computational aerodynamics and design

    NASA Technical Reports Server (NTRS)

    Ballhaus, W. F., Jr.

    1982-01-01

    The role of computational aerodynamics in design is reviewed with attention given to the design process; the proper role of computations; the importance of calibration, interpretation, and verification; the usefulness of a given computational capability; and the marketing of new codes. Examples of computational aerodynamics in design are given with particular emphasis on the Highly Maneuverable Aircraft Technology. Finally, future prospects are noted, with consideration given to the role of advanced computers, advances in numerical solution techniques, turbulence models, complex geometries, and computational design procedures. Previously announced in STAR as N82-33348

  20. Computer Aided Multi-scale Design of SiC-Si3N4 Nanoceramic Composites for High-Temperature Structural Applications

    SciTech Connect

    Vikas Tomer; John Renaud

    2010-08-31

    temperature dependent strength and microstructural stability was also significantly depended upon the dispersion of new phases at grain boundaries. The material design framework incorporates high temperature creep and mechanical strength data in order to develop a collaborative multiscale framework of morphology optimization. The work also incorporates a computer aided material design dataset development procedure where a systematic dataset on material properties and morphology correlation could be obtained depending upon a material processing scientist's requirements. Two different aspects covered under this requirement are: (1) performing morphology related analyses at the nanoscale and at the microscale to develop a multiscale material design and analyses capability; (2) linking material behavior analyses with the developed design tool to form a set of material design problems that illustrate the range of material design dataset development that could be performed. Overall, a software based methodology to design microstructure of particle based ceramic nanocomposites has been developed. This methodology has been shown to predict changes in phase morphologies required for achieving optimal balance of conflicting properties such as minimal creep strain rate and high fracture strength at high temperatures. The methodology incorporates complex material models including atomistic approaches. The methodology will be useful to design materials for high temperature applications including those of interest to DoE while significantly reducing cost of expensive experiments.

  1. Computer Aided Grid Interface: An Interactive CFD Pre-Processor

    NASA Technical Reports Server (NTRS)

    Soni, Bharat K.

    1996-01-01

    NASA maintains an applications oriented computational fluid dynamics (CFD) efforts complementary to and in support of the aerodynamic-propulsion design and test activities. This is especially true at NASA/MSFC where the goal is to advance and optimize present and future liquid-fueled rocket engines. Numerical grid generation plays a significant role in the fluid flow simulations utilizing CFD. An overall goal of the current project was to develop a geometry-grid generation tool that will help engineers, scientists and CFD practitioners to analyze design problems involving complex geometries in a timely fashion. This goal is accomplished by developing the Computer Aided Grid Interface system (CAGI). The CAGI system is developed by integrating CAD/CAM (Computer Aided Design/Computer Aided Manufacturing) geometric system output and / or Initial Graphics Exchange Specification (IGES) files (including all the NASA-IGES entities), geometry manipulations and generations associated with grid constructions, and robust grid generation methodologies. This report describes the development process of the CAGI system.

  2. Computer Aided Grid Interface: An Interactive CFD Pre-Processor

    NASA Technical Reports Server (NTRS)

    Soni, Bharat K.

    1997-01-01

    NASA maintains an applications oriented computational fluid dynamics (CFD) efforts complementary to and in support of the aerodynamic-propulsion design and test activities. This is especially true at NASA/MSFC where the goal is to advance and optimize present and future liquid-fueled rocket engines. Numerical grid generation plays a significant role in the fluid flow simulations utilizing CFD. An overall goal of the current project was to develop a geometry-grid generation tool that will help engineers, scientists and CFD practitioners to analyze design problems involving complex geometries in a timely fashion. This goal is accomplished by developing the CAGI: Computer Aided Grid Interface system. The CAGI system is developed by integrating CAD/CAM (Computer Aided Design/Computer Aided Manufacturing) geometric system output and/or Initial Graphics Exchange Specification (IGES) files (including all the NASA-IGES entities), geometry manipulations and generations associated with grid constructions, and robust grid generation methodologies. This report describes the development process of the CAGI system.

  3. The comparison of BLyS-binding peptides from phage display library and computer-aided design on BLyS-TACI interaction.

    PubMed

    Zhao, Yacong; Hao, Xiafei; Feng, Jiannan; Shen, Beifen; Wei, Jing; Sun, Jian

    2015-02-01

    BLyS antagonists have become the therapeutic reagents in the treatment of autoimmune disorders. BLyS binding peptides and their Fc fusion proteins may be alternative BLyS antagonists in such application. In this study, the activity of BLyS binding peptide 814 obtained from phage display library and peptide TA designed by computer-aided modeling on the interaction of BLyS-TACI was compared. In addition, to maintain the spatial conformation and stability of the peptides, human IgG1 Fc fragment was fused to peptides 814 and TA to form peptide-Fc fusion proteins, steady and innovative peptibodies. The prokaryotic expression plasmids pET30a-814-Fc and pET30a-TA-Fc for these peptibodies were acquired by genetic engineering, and confirmed by DNA sequencing. After the right plasmids were transformed into Escherichia coli BL21 (DE3), the fusion proteins were expressed and purified by protein A affinity column. As a result of competitive ELISA, peptides 814 and TA at 100μg/ml displayed 52.2% and 28.6% inhibition on the interaction of TACI-Fc with BLyS respectively. Moreover, 814-Fc and TA-Fc fusion proteins could bind to BLyS in a dosage-dependent manner as TACI-Fc did, and displayed 54.7% and 26.1% inhibition on the interaction of TACI-Fc-Myc with BLyS at 100μg/ml respectively. So 814-Fc and TA-Fc proteins had the similar bioactivity as the peptides did. Furthermore, compared with TA-Fc, 814-Fc showed two-fold inhibition effect on BLyS binding to TACI, suggesting that 814-Fc could inhibit BLyS bioactivity significantly and might serve as a potential antagonist to treat autoimmune diseases associated with BLyS overexpression.

  4. Computer-aided dental prostheses construction using reverse engineering.

    PubMed

    Solaberrieta, E; Minguez, R; Barrenetxea, L; Sierra, E; Etxaniz, O

    2014-01-01

    The implementation of computer-aided design/computer-aided manufacturing (CAD/CAM) systems with virtual articulators, which take into account the kinematics, constitutes a breakthrough in the construction of customised dental prostheses. This paper presents a multidisciplinary protocol involving CAM techniques to produce dental prostheses. This protocol includes a step-by-step procedure using innovative reverse engineering technologies to transform completely virtual design processes into customised prostheses. A special emphasis is placed on a novel method that permits a virtual location of the models. The complete workflow includes the optical scanning of the patient, the use of reverse engineering software and, if necessary, the use of rapid prototyping to produce CAD temporary prostheses.

  5. Survey of Intelligent Computer-Aided Training

    NASA Technical Reports Server (NTRS)

    Loftin, R. B.; Savely, Robert T.

    1992-01-01

    Intelligent Computer-Aided Training (ICAT) systems integrate artificial intelligence and simulation technologies to deliver training for complex, procedural tasks in a distributed, workstation-based environment. Such systems embody both the knowledge of how to perform a task and how to train someone to perform that task. This paper briefly reviews the antecedents of ICAT systems and describes the approach to their creation developed at the NASA Lyndon B. Johnson Space Center. In addition to the general ICAT architecture, specific ICAT applications that have been or are currently under development are discussed. ICAT systems can offer effective solutions to a number of training problems of interest to the aerospace community.

  6. Computer-aided forensic facial reconstruction.

    PubMed

    Evenhouse, R; Rasmussen, M; Sadler, L

    1992-01-01

    The reconstruction of facial features on the human skull for identification purposes has, in the past, utilized either two-dimensional drafting or three-dimensional sculpting techniques. We have developed two- and three-dimensional computer-aided routines to minimize errors introduced by limits of artistic ability or by inconsistencies in the application of techniques. These routines allow generalized facial features to be manipulated to conform to the size and shape of a specific skull. Subtle alterations of the surface form, texture, and color, based on age, sex, and race, enhance the individuality of the generated facial form. PMID:1624477

  7. Characterization of hydrophilic-rich phase mimic in dentin adhesive and computer-aided molecular design of water compatible visible light initiators

    NASA Astrophysics Data System (ADS)

    Abedin, Farhana

    infiltration of these noxious agents at the interface between the material and tooth could pave the way for enhanced degradation of the tooth structure (collagen and mineral) as well as the adhesive polymer. Novel photosensitizer molecules were proposed to improve the polymerization efficiency of this phase. Computer-aided molecular design (CAMD) was employed to obtain the new photosensitizers. These photosensitizers were capable of improving the degree of conversion of the hydrophilic-rich phase. An enhanced degree of conversion of the hydrophilic-rich phase would lead to a better seal at the adhesive/dentin interface and higher bond strength. Computer-aided molecular design (CAMD) is a fast and inexpensive technique compared to the conventional trial-and-error method to rationally design products. (Abstract shortened by ProQuest.).

  8. Effective Computer Aided Instruction in Biomedical Science

    PubMed Central

    Hause, Lawrence L.

    1985-01-01

    A menu-driven Computer Aided Instruction (CAI) package was integrated with word processing and effectively applied in five curricula at the Medical College of Wisconsin. Integration with word processing facilitates the ease of CAI development by instructors and was found to be the most important step in the development of CAI. CAI modules were developed and are currently used to reinforce lectures in medical pathology, laboratory quality control, computer programming and basic science reviews of medicine. Modules help the lecturer efficiently cover fundamentals and provide the student with a self-directed learning alternative. A structured approach to CAI has helped build a CAI program which supports other traditional modes of instruction at MCW.

  9. Emergency Management Computer-Aided Trainer (EMCAT)

    NASA Technical Reports Server (NTRS)

    Rodriguez, R. C.; Johnson, R. P.

    1986-01-01

    The Emergency Management Computer-Aided Trainer (EMCAT) developed by Essex Corporation or NASA and the Federal Emergency Management Administration's (FEMA) National Fire Academy (NFA) is described. It is a computer based training system for fire fighting personnel. A prototype EMCAT system was developed by NASA first using video tape images and then video disk images when the technology became available. The EMCAT system is meant to fill the training needs of the fire fighting community with affordable state-of-the-art technologies. An automated real time simulation of the fire situation was needed to replace the outdated manual training methods currently being used. In order to be successful, this simulator had to provide realism, be user friendly, be affordable, and support multiple scenarios. The EMCAT system meets these requirements and therefore represents an innovative training tool, not only for the fire fighting community, but also for the needs of other disciplines.

  10. A Suggested Computer Aided Drafting Curriculum (Dacum Based).

    ERIC Educational Resources Information Center

    Pedras, Melvin J.; Hoggard, David

    Computer-aided drawing can bring new technology into the drafting classroom. One approach to computer-aided drafting (CAD) involves use of a personal computer and purchased software. Existing school computers could be shared to reduce costs. Following this narrative introduction, a suggested curriculum for the teaching of CAD is presented in…

  11. 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.

  12. A Report from ICAMI: The Institute for Computer-Aided Mathematics Instruction.

    ERIC Educational Resources Information Center

    Avery, Chris

    De Anza College's Institute for Computer-Aided Mathematics Instruction (ICAMI) is a direct outgrowth of the computer-aided mathematics program, in California, started at the California college in 1982. ICAMI focuses on the design and dissemination of effective instructional models for: (1) skill building for more efficient problem solving,…

  13. Artwork Interactive Design System (AIDS) program description

    NASA Technical Reports Server (NTRS)

    Johnson, B. T.; Taylor, J. F.

    1976-01-01

    An artwork interactive design system is described which provides the microelectronic circuit designer/engineer a tool to perform circuit design, automatic layout modification, standard cell design, and artwork verification at a graphics computer terminal using a graphics tablet at the designer/computer interface.

  14. Application of Particle Swarm Optimization in Computer Aided Setup Planning

    NASA Astrophysics Data System (ADS)

    Kafashi, Sajad; Shakeri, Mohsen; Abedini, Vahid

    2011-01-01

    New researches are trying to integrate computer aided design (CAD) and computer aided manufacturing (CAM) environments. The role of process planning is to convert the design specification into manufacturing instructions. Setup planning has a basic role in computer aided process planning (CAPP) and significantly affects the overall cost and quality of machined part. This research focuses on the development for automatic generation of setups and finding the best setup plan in feasible condition. In order to computerize the setup planning process, three major steps are performed in the proposed system: a) Extraction of machining data of the part. b) Analyzing and generation of all possible setups c) Optimization to reach the best setup plan based on cost functions. Considering workshop resources such as machine tool, cutter and fixture, all feasible setups could be generated. Then the problem is adopted with technological constraints such as TAD (tool approach direction), tolerance relationship and feature precedence relationship to have a completely real and practical approach. The optimal setup plan is the result of applying the PSO (particle swarm optimization) algorithm into the system using cost functions. A real sample part is illustrated to demonstrate the performance and productivity of the system.

  15. Microstereolithography-based computer-aided manufacturing for tissue engineering.

    PubMed

    Cho, Dong-Woo; Kang, Hyun-Wook

    2012-01-01

    Various solid freeform fabrication technologies have been introduced for constructing three-dimensional (3-D) freeform structures. Of these, microstereolithography (MSTL) technology performs the best in 3-D space because it not only has high resolution, but also fast fabrication speed. Using this technology, 3-D structures with mesoscale size and microscale resolution are achievable. Many researchers have been trying to apply this technology to tissue engineering to construct medically applicable scaffolds, which require a 3-D shape that fits a defect with a mesoscale size and microscale inner architecture for efficient regeneration of artificial tissue. This chapter introduces the principles of MSTL technology and representative systems. It includes fabrication and computer-aided design/computer-aided manufacturing (CAD/CAM) processes to show the automation process by which measurements from medical images are used to fabricate the required 3-D shape. Then, various tissue engineering applications based on MSTL are summarized.

  16. Uncertainty management in intelligent design aiding systems

    NASA Technical Reports Server (NTRS)

    Brown, Donald E.; Gabbert, Paula S.

    1988-01-01

    A novel approach to uncertainty management which is particularly effective in intelligent design aiding systems for large-scale systems is presented. The use of this approach in the materials handling system design domain is discussed. It is noted that, during any point in the design process, a point value can be obtained for the evaluation of feasible designs; however, the techniques described provide unique solutions for these point values using only the current information about the design environment.

  17. Computational Geometry and Computer-Aided Design

    NASA Technical Reports Server (NTRS)

    Fay, T. H. (Compiler); Shoosmith, J. N. (Compiler)

    1985-01-01

    Extended abstracts of papers addressing the analysis, representation, and synthesis of shape information are presented. Curves and shape control, grid generation and contouring, solid modelling, surfaces, and curve intersection are specifically addressed.

  18. Computer aided diagnosis of diabetic peripheral neuropathy

    NASA Astrophysics Data System (ADS)

    Chekh, Viktor; Soliz, Peter; McGrew, Elizabeth; Barriga, Simon; Burge, Mark; Luan, Shuang

    2014-03-01

    Diabetic peripheral neuropathy (DPN) refers to the nerve damage that can occur in diabetes patients. It most often affects the extremities, such as the feet, and can lead to peripheral vascular disease, deformity, infection, ulceration, and even amputation. The key to managing diabetic foot is prevention and early detection. Unfortunately, current existing diagnostic techniques are mostly based on patient sensations and exhibit significant inter- and intra-observer differences. We have developed a computer aided diagnostic (CAD) system for diabetic peripheral neuropathy. The thermal response of the feet of diabetic patients following cold stimulus is captured using an infrared camera. The plantar foot in the images from a thermal video are segmented and registered for tracking points or specific regions. The temperature recovery of each point on the plantar foot is extracted using our bio-thermal model and analyzed. The regions that exhibit abnormal ability to recover are automatically identified to aid the physicians to recognize problematic areas. The key to our CAD system is the segmentation of infrared video. The main challenges for segmenting infrared video compared to normal digital video are (1) as the foot warms up, it also warms up the surrounding, creating an ever changing contrast; and (2) there may be significant motion during imaging. To overcome this, a hybrid segmentation algorithm was developed based on a number of techniques such as continuous max-flow, model based segmentation, shape preservation, convex hull, and temperature normalization. Verifications of the automatic segmentation and registration using manual segmentation and markers show good agreement.

  19. An Expert Assistant for Computer Aided Parallelization

    NASA Technical Reports Server (NTRS)

    Jost, Gabriele; Chun, Robert; Jin, Haoqiang; Labarta, Jesus; Gimenez, Judit

    2004-01-01

    The prototype implementation of an expert system was developed to assist the user in the computer aided parallelization process. The system interfaces to tools for automatic parallelization and performance analysis. By fusing static program structure information and dynamic performance analysis data the expert system can help the user to filter, correlate, and interpret the data gathered by the existing tools. Sections of the code that show poor performance and require further attention are rapidly identified and suggestions for improvements are presented to the user. In this paper we describe the components of the expert system and discuss its interface to the existing tools. We present a case study to demonstrate the successful use in full scale scientific applications.

  20. Computer aided control of a mechanical arm

    NASA Technical Reports Server (NTRS)

    Derocher, W. L., Jr.; Zermuehlen, r. O.

    1979-01-01

    A method for computer-aided remote control of a six-degree-of-freedom manipulator arm involved in the on-orbit servicing of a spacecraft is presented. The control configuration features a supervisory type of control in which each of the segments of a module exchange trajectory is controlled automatically under human supervision, with manual commands to proceed to the next step and in the event of a failure or undesirable outcome. The implementation of the supervisory system is discussed in terms of necessary onboard and ground- or Orbiter-based hardware and software, and a one-g demonstration system built to allow further investigation of system operation is described. Possible applications of the system include the construction of satellite solar power systems, environmental testing and the control of heliostat solar power stations.

  1. Computer-aided analysis of optical data link (Poster Paper)

    NASA Astrophysics Data System (ADS)

    Lin, Jizoo; Wang, Yuh-Diahn; Shih, Ming-Tang

    1992-10-01

    This paper presents a fiber optic simulation methodology for the design of digital lightwave link. Computer-aided analysis of high speed optical data link is important for a system designer to predict the system performance in advanced. Accurate modeling and simulation contribute the fundamental evaluation of optical communication integrated circuit feasibilities. In this paper, the modeling of optical source waveform, transmission fiber, photodetector and timing recovery technique using surface acoustic wave (SAW) filter are discussed. A SONET OC-3 transceiver is simulated as an example, while measured eye diagrams are compared with the simulation result.

  2. RASCAL: A Rudimentary Adaptive System for Computer-Aided Learning.

    ERIC Educational Resources Information Center

    Stewart, John Christopher

    Both the background of computer-assisted instruction (CAI) systems in general and the requirements of a computer-aided learning system which would be a reasonable assistant to a teacher are discussed. RASCAL (Rudimentary Adaptive System for Computer-Aided Learning) is a first attempt at defining a CAI system which would individualize the learning…

  3. Computer automated design and computer automated manufacture.

    PubMed

    Brncick, M

    2000-08-01

    The introduction of computer aided design and computer aided manufacturing into the field of prosthetics and orthotics did not arrive without concern. Many prosthetists feared that the computer would provide other allied health practitioners who had little or no experience in prosthetics the ability to fit and manage amputees. Technicians in the field felt their jobs may be jeopardized by automated fabrication techniques. This has not turned out to be the case. Prosthetists who use CAD-CAM techniques are finding they have more time for patient care and clinical assessment. CAD-CAM is another tool for them to provide better care for the patients/clients they serve. One of the factors that deterred the acceptance of CAD-CAM techniques in its early stages was that of cost. It took a significant investment in software and hardware for the prosthetists to begin to use the new systems. This new technique was not reimbursed by insurance coverage. Practitioners did not have enough information about this new technique to make a sound decision on their investment of time and money. Ironically, it is the need to hold health care costs down that may prove to be the catalyst for the increased use of CAD-CAM in the field. Providing orthoses and prostheses to patients who require them is a very labor intensive process. Practitioners are looking for better, faster, and more economical ways in which to provide their services under the pressure of managed care. CAD-CAM may be the answer. The author foresees shape sensing departments in hospitals where patients would be sent to be digitized, similar to someone going for radiograph or ultrasound. Afterwards, an orthosis or prosthesis could be provided from a central fabrication facility at a remote site, most likely on the same day. Not long ago, highly skilled practitioners with extensive technical ability would custom make almost every orthosis. One now practices in an atmosphere where off-the-shelf orthoses are the standard. This

  4. Markovian chemicals "in silico" design (MARCH-INSIDE), a promising approach for computer-aided molecular design I: discovery of anticancer compounds.

    PubMed

    Gonzáles-Díaz, Humberto; Gia, Ornella; Uriarte, Eugenio; Hernádez, Ivan; Ramos, Ronal; Chaviano, Mayrelis; Seijo, Santiago; Castillo, Juan A; Morales, Lázaro; Santana, Lourdes; Akpaloo, Delali; Molina, Enrique; Cruz, Maikel; Torres, Luis A; Cabrera, Miguel A

    2003-12-01

    A simple stochastic approach, designed to model the movement of electrons throughout chemical bonds, is introduced. This model makes use of a Markov matrix to codify useful structural information in QSAR. The self-return probabilities of this matrix throughout time ((SR)pi(k)) are then used as molecular descriptors. Firstly, a calculation of (SR)pi(k) is made for a large series of anticancer and non-anticancer chemicals. Then, k-Means Cluster Analysis allows us to split the data series into clusters and ensure a representative design of training and predicting series. Next, we develop a classification function through Linear Discriminant Analysis (LDA). This QSAR discriminates between anticancer compounds and non-active compounds with a correct global classification of 90.5% in the training series. The model also correctly classified 86.07% of the compounds in the predicting series. This classification function is then used to perform a virtual screening of a combinatorial library of coumarins. In this connection, the biological assay of some furocoumarins, selected by virtual screening using the present model, gives good results. In particular, a tetracyclic derivative of 5-methoxypsoralen (5-MOP) has an IC50 against HL-60 tumoral line around 6 to 10 times lower than those for 8-MOP and 5-MOP (reference drugs), respectively. Finally, application of Iso-contribution Zone Analysis (IZA) provides structural interpretation of the biological activity predicted with this QSAR. PMID:13680309

  5. Three-Dimensional Planning in Maxillofacial Fracture Surgery: Computer-Aided Design/Computer-Aided Manufacture Surgical Splints by Integrating Cone Beam Computerized Tomography Images Into Multislice Computerized Tomography Images.

    PubMed

    Ren, Jiayin; Zhou, Zhongwei; Li, Peng; Tang, Wei; Guo, Jixiang; Wang, Hu; Tian, Weidong

    2016-09-01

    This study aimed to evaluate an innovative workflow for maxillofacial fracture surgery planning and surgical splint designing. The maxillofacial multislice computerized tomography (MSCT) data and dental cone beam computerized tomography (CBCT) data both were obtained from 40 normal adults and 58 adults who suffered fractures. The each part of the CBCT dentition image was registered into MSCT image by the use of the iterative closest point algorithm. Volume evaluation of the virtual splints that were designed by the registered MSCT images and MSCT images of the same object was performed. Eighteen patients (group 1) were operated without any splint. Twenty-one (group 2) and 19 patients (group 3) used the splints designed according to the MSCT images and registered MSCT images, respectively. The authors' results showed that the mean errors between the 2 models ranged from 0.53 to 0.92 mm and the RMS errors ranged from 0.38 to 0.69 mm in fracture patients. The mean errors between the 2 models ranged from 0.47 to 0.85 mm and the RMS errors ranged from 0.33 to 0.71 mm in normal adults. 72.22% patients in group 1 recovered occlusion. 85.71% patients in group 2, and 94.73% patients in group 3 reconstructed occlusion. There was a statistically significant difference between the MSCT images based splints' volume and the registered MSCT splints' volume in patients (P <0.05). The MSCT images based splints' volume was statistically significantly distinct from the registered MSCT splints' volume in normal adults (P <0.05). There was a statistically significant difference between the MSCT images based splints' volume and the registered MSCT splints' volume in patients and normal adults (P <0.05). The occlusion recovery rate of group 3 was better than that of group 1 and group 2. The way of integrating CBCT images into MSCT images for splints designing was feasible. The volume of the splints designed by MSCT images tended to be smaller than the splints designed by

  6. Three-Dimensional Planning in Maxillofacial Fracture Surgery: Computer-Aided Design/Computer-Aided Manufacture Surgical Splints by Integrating Cone Beam Computerized Tomography Images Into Multislice Computerized Tomography Images.

    PubMed

    Ren, Jiayin; Zhou, Zhongwei; Li, Peng; Tang, Wei; Guo, Jixiang; Wang, Hu; Tian, Weidong

    2016-09-01

    This study aimed to evaluate an innovative workflow for maxillofacial fracture surgery planning and surgical splint designing. The maxillofacial multislice computerized tomography (MSCT) data and dental cone beam computerized tomography (CBCT) data both were obtained from 40 normal adults and 58 adults who suffered fractures. The each part of the CBCT dentition image was registered into MSCT image by the use of the iterative closest point algorithm. Volume evaluation of the virtual splints that were designed by the registered MSCT images and MSCT images of the same object was performed. Eighteen patients (group 1) were operated without any splint. Twenty-one (group 2) and 19 patients (group 3) used the splints designed according to the MSCT images and registered MSCT images, respectively. The authors' results showed that the mean errors between the 2 models ranged from 0.53 to 0.92 mm and the RMS errors ranged from 0.38 to 0.69 mm in fracture patients. The mean errors between the 2 models ranged from 0.47 to 0.85 mm and the RMS errors ranged from 0.33 to 0.71 mm in normal adults. 72.22% patients in group 1 recovered occlusion. 85.71% patients in group 2, and 94.73% patients in group 3 reconstructed occlusion. There was a statistically significant difference between the MSCT images based splints' volume and the registered MSCT splints' volume in patients (P <0.05). The MSCT images based splints' volume was statistically significantly distinct from the registered MSCT splints' volume in normal adults (P <0.05). There was a statistically significant difference between the MSCT images based splints' volume and the registered MSCT splints' volume in patients and normal adults (P <0.05). The occlusion recovery rate of group 3 was better than that of group 1 and group 2. The way of integrating CBCT images into MSCT images for splints designing was feasible. The volume of the splints designed by MSCT images tended to be smaller than the splints designed by

  7. Aids in designing laboratory flumes

    USGS Publications Warehouse

    Williams, Garnett P.

    1971-01-01

    The upsurge of interest in our environment has caused research and instruction in the flow of water along open channels to become increasingly popular in universities and institutes. This, in turn, has brought a greater demand for properly-designed laboratory flumes. Whatever the reason for your interest, designing and building the flume will take a little preparation. You may choose a pattern exactly like a previous design, or you may follow the more time-consuming method of studying several existing flumes and combine the most desirable features of each.

  8. Biomimetic design processes in architecture: morphogenetic and evolutionary computational design.

    PubMed

    Menges, Achim

    2012-03-01

    Design computation has profound impact on architectural design methods. This paper explains how computational design enables the development of biomimetic design processes specific to architecture, and how they need to be significantly different from established biomimetic processes in engineering disciplines. The paper first explains the fundamental difference between computer-aided and computational design in architecture, as the understanding of this distinction is of critical importance for the research presented. Thereafter, the conceptual relation and possible transfer of principles from natural morphogenesis to design computation are introduced and the related developments of generative, feature-based, constraint-based, process-based and feedback-based computational design methods are presented. This morphogenetic design research is then related to exploratory evolutionary computation, followed by the presentation of two case studies focusing on the exemplary development of spatial envelope morphologies and urban block morphologies.

  9. Rapid Geometry Creation for Computer-Aided Engineering Parametric Analyses: A Case Study Using ComGeom2 for Launch Abort System Design

    NASA Technical Reports Server (NTRS)

    Hawke, Veronica; Gage, Peter; Manning, Ted

    2007-01-01

    ComGeom2, a tool developed to generate Common Geometry representation for multidisciplinary analysis, has been used to create a large set of geometries for use in a design study requiring analysis by two computational codes. This paper describes the process used to generate the large number of configurations and suggests ways to further automate the process and make it more efficient for future studies. The design geometry for this study is the launch abort system of the NASA Crew Launch Vehicle.

  10. The computer-aided facial reconstruction system.

    PubMed

    Miyasaka, S; Yoshino, M; Imaizumi, K; Seta, S

    1995-06-30

    A computer imaging system was introduced into the facial reconstruction process. The system, which consists of the image processing unit for skull morphometry and the image editing unit for compositing facial components on the skull images, was an original construction. The image processor generates the framework for building a face onto the digitized skull image. For reconstructing a facial image on the framework, several possible data sets of facial components suitable for the skull morphology are selected from the database by operating our original application software. The most suitable cutout samples of facial components are pasted up over the framework in accordance with the anatomical criteria. The database of facial components consists of 24 contours, 18 eyes, 9 eyebrows, 27 noses, 9 lips and 16 hairstyles. After provisional reconstruction, the facial image is retouched by correcting skin colors and shades with an 'electronic painting device'. The resulting image is a great improvement on images made by the conventional clay and drawing method, both in the operational aspect and in the flexibility of creating multiple versions. The present system facilitates a rather objective and rapid approach and allows us easily to generate a range of possible faces. The computer-aided facial reconstruction will lead to an increase in chances of positive identification in practical cases.

  11. Computer aided detection system for clustered microcalcifications

    PubMed Central

    Ge, Jun; Hadjiiski, Lubomir M.; Sahiner, Berkman; Wei, Jun; Helvie, Mark A.; Zhou, Chuan; Chan, Heang-Ping

    2009-01-01

    We have developed a computer-aided detection (CAD) system to detect clustered microcalcification automatically on full-field digital mammograms (FFDMs) and a CAD system for screen-film mammograms (SFMs). The two systems used the same computer vision algorithms but their false positive (FP) classifiers were trained separately with sample images of each modality. In this study, we compared the performance of the CAD systems for detection of clustered microcalcifications on pairs of FFDM and SFM obtained from the same patient. For case-based performance evaluation, the FFDM CAD system achieved detection sensitivities of 70%, 80%, and 90% at an average FP cluster rate of 0.07, 0.16, and 0.63 per image, compared with an average FP cluster rate of 0.15, 0.38, and 2.02 per image for the SFM CAD system. The difference was statistically significant with the alternative free-response receiver operating characteristic (AFROC) analysis. When evaluated on data sets negative for microcalcification clusters, the average FP cluster rates of the FFDM CAD system were 0.04, 0.11, and 0.33 per image at detection sensitivity level of 70%, 80%, and 90%, compared with an average FP cluster rate of 0.08, 0.14, and 0.50 per image for the SFM CAD system. When evaluated for malignant cases only, the difference of the performance of the two CAD systems was not statistically significant with AFROC analysis. PMID:17264365

  12. The Island of Terra: A Computer-Aided Simulation of World Resources Problems Designed for Lower-Achieving Secondary School Pupils.

    ERIC Educational Resources Information Center

    Watson, Robert

    1983-01-01

    Describes the computer-assisted environmental-educational game TERRA, which is designed to encourage lower-ability high school students to think at their own level about the future of their world. Based on "The Limits to Growth" (Meadows et al., 1972), the game comprises four programs: Terra Firma, Terradactyl, Inflation, and Doubles. (EAO)

  13. Computer aided radiation analysis for manned spacecraft

    NASA Technical Reports Server (NTRS)

    Appleby, Matthew H.; Griffin, Brand N.; Tanner, Ernest R., II; Pogue, William R.; Golightly, Michael J.

    1991-01-01

    In order to assist in the design of radiation shielding an analytical tool is presented that can be employed in combination with CAD facilities and NASA transport codes. The nature of radiation in space is described, and the operational requirements for protection are listed as background information for the use of the technique. The method is based on the Boeing radiation exposure model (BREM) for combining NASA radiation transport codes and CAD facilities, and the output is given as contour maps of the radiation-shield distribution so that dangerous areas can be identified. Computational models are used to solve the 1D Boltzmann transport equation and determine the shielding needs for the worst-case scenario. BREM can be employed directly with the radiation computations to assess radiation protection during all phases of design which saves time and ultimately spacecraft weight.

  14. Program Aids Design Of Fluid-Circulating Systems

    NASA Technical Reports Server (NTRS)

    Bacskay, Allen; Dalee, Robert

    1992-01-01

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

  15. Computer Designed Instruction & Testing.

    ERIC Educational Resources Information Center

    New Mexico State Univ., Las Cruces.

    Research findings on computer designed instruction and testing at the college level are discussed in 13 papers from the first Regional Conference on University Teaching at New Mexico State University. Titles and authors are as follows: "Don't Bother Me with Instructional Design, I'm Busy Programming! Suggestions for More Effective Educational…

  16. Volume accumulator design analysis computer codes

    NASA Technical Reports Server (NTRS)

    Whitaker, W. D.; Shimazaki, T. T.

    1973-01-01

    The computer codes, VANEP and VANES, were written and used to aid in the design and performance calculation of the volume accumulator units (VAU) for the 5-kwe reactor thermoelectric system. VANEP computes the VAU design which meets the primary coolant loop VAU volume and pressure performance requirements. VANES computes the performance of the VAU design, determined from the VANEP code, at the conditions of the secondary coolant loop. The codes can also compute the performance characteristics of the VAU's under conditions of possible modes of failure which still permit continued system operation.

  17. Automatic computer-aided system of simulating solder joint formation

    NASA Astrophysics Data System (ADS)

    Zhao, Xiujuan; Wang, Chunqing; Zheng, Guanqun; Wang, Gouzhong; Yang, Shiqin

    1999-08-01

    One critical aspect in electronic packaging is the fatigue/creep-induced failure in solder interconnections, which is found to be highly dependent on the shape of solder joints. Thus predicting and analyzing the solder joint shape is warranted. In this paper, an automatic computer-aided system is developed to simulate the formation of solder joint and analyze the influence of the different process parameters on the solder joint shape. The developed system is capable of visually designing the process parameters and calculating the solder joint shape automatically without any intervention from the user. The automation achieved will enable fast shape estimation with the variation of process parameters without time consuming experiments, and the simulating system provides the design and manufacturing engineers an efficient software tools to design soldering process in design environment. Moreover, a program developed from the system can serve as the preprocessor for subsequent finite element joint analysis program.

  18. Computer-Aided Parallelizer and Optimizer

    NASA Technical Reports Server (NTRS)

    Jin, Haoqiang

    2011-01-01

    The Computer-Aided Parallelizer and Optimizer (CAPO) automates the insertion of compiler directives (see figure) to facilitate parallel processing on Shared Memory Parallel (SMP) machines. While CAPO currently is integrated seamlessly into CAPTools (developed at the University of Greenwich, now marketed as ParaWise), CAPO was independently developed at Ames Research Center as one of the components for the Legacy Code Modernization (LCM) project. The current version takes serial FORTRAN programs, performs interprocedural data dependence analysis, and generates OpenMP directives. Due to the widely supported OpenMP standard, the generated OpenMP codes have the potential to run on a wide range of SMP machines. CAPO relies on accurate interprocedural data dependence information currently provided by CAPTools. Compiler directives are generated through identification of parallel loops in the outermost level, construction of parallel regions around parallel loops and optimization of parallel regions, and insertion of directives with automatic identification of private, reduction, induction, and shared variables. Attempts also have been made to identify potential pipeline parallelism (implemented with point-to-point synchronization). Although directives are generated automatically, user interaction with the tool is still important for producing good parallel codes. A comprehensive graphical user interface is included for users to interact with the parallelization process.

  19. Developing an Intelligent Computer-Aided Trainer

    NASA Technical Reports Server (NTRS)

    Hua, Grace

    1990-01-01

    The Payload-assist module Deploys/Intelligent Computer-Aided Training (PD/ICAT) system was developed as a prototype for intelligent tutoring systems with the intention of seeing PD/ICAT evolve and produce a general ICAT architecture and development environment that can be adapted by a wide variety of training tasks. The proposed architecture is composed of a user interface, a domain expert, a training session manager, a trainee model and a training scenario generator. The PD/ICAT prototype was developed in the LISP environment. Although it has been well received by its peers and users, it could not be delivered toe its end users for practical use because of specific hardware and software constraints. To facilitate delivery of PD/ICAT to its users and to prepare for a more widely accepted development and delivery environment for future ICAT applications, we have ported this training system to a UNIX workstation and adopted use of a conventional language, C, and a C-based rule-based language, CLIPS. A rapid conversion of the PD/ICAT expert system to CLIPS was possible because the knowledge was basically represented as a forward chaining rule base. The resulting CLIPS rule base has been tested successfully in other ICATs as well. Therefore, the porting effort has proven to be a positive step toward our ultimate goal of building a general purpose ICAT development environment.

  20. 3D volume assessment techniques and computer-aided design and manufacturing for preoperative fabrication of implants in head and neck reconstruction.

    PubMed

    Patel, Ashish; Otterburn, David; Saadeh, Pierre; Levine, Jamie; Hirsch, David L

    2011-11-01

    Cases in subdisciplines of craniomaxillofacial surgery--corrective jaw surgery, maxillofacial trauma, temporomandibular joint/skull base, jaw reconstruction, and postablative reconstruction-illustrate the ease of use, cost effectiveness, and superior results that can be achieved when using computer-assisted design and 3D volumetric analysis in preoperative surgical planning. This article discusses the materials and methods needed to plan cases, illustrates implementation of guides and implants, and describes postoperative analysis in relation to the virtually planned surgery.

  1. Simulation as an Aid to Experimental Design.

    ERIC Educational Resources Information Center

    Frazer, Jack W.; And Others

    1983-01-01

    Discusses simulation program to aid in the design of enzyme kinetic experimentation (includes sample runs). Concentration versus time profiles of any subset or all nine states of reactions can be displayed with/without simulated instrumental noise, allowing the user to estimate the practicality of any proposed experiment given known instrument…

  2. Computer aided analysis, simulation and optimisation of thermal sterilisation processes.

    PubMed

    Narayanan, C M; Banerjee, Arindam

    2013-04-01

    Although thermal sterilisation is a widely employed industrial process, little work is reported in the available literature including patents on the mathematical analysis and simulation of these processes. In the present work, software packages have been developed for computer aided optimum design of thermal sterilisation processes. Systems involving steam sparging, jacketed heating/cooling, helical coils submerged in agitated vessels and systems that employ external heat exchangers (double pipe, shell and tube and plate exchangers) have been considered. Both batch and continuous operations have been analysed and simulated. The dependence of del factor on system / operating parameters such as mass or volume of substrate to be sterilised per batch, speed of agitation, helix diameter, substrate to steam ratio, rate of substrate circulation through heat exchanger and that through holding tube have been analysed separately for each mode of sterilisation. Axial dispersion in the holding tube has also been adequately accounted for through an appropriately defined axial dispersion coefficient. The effect of exchanger characteristics/specifications on the system performance has also been analysed. The multiparameter computer aided design (CAD) software packages prepared are thus highly versatile in nature and they permit to make the most optimum choice of operating variables for the processes selected. The computed results have been compared with extensive data collected from a number of industries (distilleries, food processing and pharmaceutical industries) and pilot plants and satisfactory agreement has been observed between the two, thereby ascertaining the accuracy of the CAD softwares developed. No simplifying assumptions have been made during the analysis and the design of associated heating / cooling equipment has been performed utilising the most updated design correlations and computer softwares. PMID:23294402

  3. Computer aided analysis, simulation and optimisation of thermal sterilisation processes.

    PubMed

    Narayanan, C M; Banerjee, Arindam

    2013-04-01

    Although thermal sterilisation is a widely employed industrial process, little work is reported in the available literature including patents on the mathematical analysis and simulation of these processes. In the present work, software packages have been developed for computer aided optimum design of thermal sterilisation processes. Systems involving steam sparging, jacketed heating/cooling, helical coils submerged in agitated vessels and systems that employ external heat exchangers (double pipe, shell and tube and plate exchangers) have been considered. Both batch and continuous operations have been analysed and simulated. The dependence of del factor on system / operating parameters such as mass or volume of substrate to be sterilised per batch, speed of agitation, helix diameter, substrate to steam ratio, rate of substrate circulation through heat exchanger and that through holding tube have been analysed separately for each mode of sterilisation. Axial dispersion in the holding tube has also been adequately accounted for through an appropriately defined axial dispersion coefficient. The effect of exchanger characteristics/specifications on the system performance has also been analysed. The multiparameter computer aided design (CAD) software packages prepared are thus highly versatile in nature and they permit to make the most optimum choice of operating variables for the processes selected. The computed results have been compared with extensive data collected from a number of industries (distilleries, food processing and pharmaceutical industries) and pilot plants and satisfactory agreement has been observed between the two, thereby ascertaining the accuracy of the CAD softwares developed. No simplifying assumptions have been made during the analysis and the design of associated heating / cooling equipment has been performed utilising the most updated design correlations and computer softwares.

  4. Technology's Edge: The Educational Benefits of Computer-Aided Instruction. NBER Working Paper No. 14240

    ERIC Educational Resources Information Center

    Barrow, Lisa; Markman, Lisa; Rouse, Cecilia E.

    2008-01-01

    We present results from a randomized study of a well-defined use of computers in schools: a popular instructional computer program for pre-algebra and algebra. We assess the program using a test designed to target pre-algebra and algebra skills. Students randomly assigned to computer-aided instruction score 0.17 of a standard deviation higher on…

  5. Computer Assisted Instructional Design for Computer-Based Instruction. Final Report. Working Papers.

    ERIC Educational Resources Information Center

    Russell, Daniel M.; Pirolli, Peter

    Recent advances in artificial intelligence and the cognitive sciences have made it possible to develop successful intelligent computer-aided instructional systems for technical and scientific training. In addition, computer-aided design (CAD) environments that support the rapid development of such computer-based instruction have also been recently…

  6. Mammographic computer-aided detection systems.

    PubMed

    2003-04-01

    While mammography is regarded as the best means available to screen for breast cancer, reading mammograms is a tedious, error-prone task. Given the repetitiveness of the process and the fact that less than 1% of mammograms in the average screening population contain cancer, it's no wonder that a significant number of breast cancers--about 28%--are missed by radiologists. The fact that human error is such a significant obstacle makes mammography screening an ideal application for computer-aided detection (CAD) systems. CAD systems serve as a "second pair of eyes" to ensure that radiologists don't miss a suspect area on an image. They analyze patterns on a digitized mammographic image, identify regions that may contain an abnormality indicating cancer, and mark these regions. The marks are then inspected and classified by a radiologist. But CAD systems provide no diagnosis of any kind--it's up to the radiologist to analyze the marked area and decide if it shows cancer. In this Evaluation, we describe the challenges posed by screening mammography, the operating principles and overall efficacy of CAD systems, and the characteristics to consider when purchasing a system. We also compare the performance of two commercially available systems, iCAD's MammoReader and R2's ImageChecker. Because the two systems offer comparable sensitivity, our judgments are based on other performance characteristics, including their ease of use, the number of false marks they produce, the degree to which they can integrate with hospital information systems, and their processing speed.

  7. Software Aids Visualization of Computed Unsteady Flow

    NASA Technical Reports Server (NTRS)

    Kao, David; Kenwright, David

    2003-01-01

    Unsteady Flow Analysis Toolkit (UFAT) is a computer program that synthesizes motions of time-dependent flows represented by very large sets of data generated in computational fluid dynamics simulations. Prior to the development of UFAT, it was necessary to rely on static, single-snapshot depictions of time-dependent flows generated by flow-visualization software designed for steady flows. Whereas it typically takes weeks to analyze the results of a largescale unsteady-flow simulation by use of steady-flow visualization software, the analysis time is reduced to hours when UFAT is used. UFAT can be used to generate graphical objects of flow visualization results using multi-block curvilinear grids in the format of a previously developed NASA data-visualization program, PLOT3D. These graphical objects can be rendered using FAST, another popular flow visualization software developed at NASA. Flow-visualization techniques that can be exploited by use of UFAT include time-dependent tracking of particles, detection of vortex cores, extractions of stream ribbons and surfaces, and tetrahedral decomposition for optimal particle tracking. Unique computational features of UFAT include capabilities for automatic (batch) processing, restart, memory mapping, and parallel processing. These capabilities significantly reduce analysis time and storage requirements, relative to those of prior flow-visualization software. UFAT can be executed on a variety of supercomputers.

  8. Design and use of improved walking aids.

    PubMed

    Nava, L C; Laura, P A

    1985-10-01

    The design of crutches and walking sticks to assist the disabled has not varied much since their original conception, some 5000 years ago. From an engineering viewpoint one must consider crutches and walking sticks as dynamic mechanical systems which alleviate a disability; they may act as supports, help the user to recover from stumbling, or transmit from the arms, the energy required to lift the feet from the ground, an action not provided by artificial ankle joints. We describe some dynamic walking aids recently developed at the Instituto de Mecánica Aplicada, and discuss their design and our experience with their use. They are adjustable in height, shock absorbing and have non-slipping tips. Specially developed aids have been designed for children; they are versatile and their use has been made psychologically attractive.

  9. Effect of type of practice in a computer-aided design environment in visualizing three-dimensional objects from two-dimensional orthographic projections.

    PubMed

    Duesbury, R T; O'Neil, H F

    1996-06-01

    The purpose of this study was to determine the effect of practice in manipulating 2- and 3-dimensional (D) wireframe images on a learner's ability to visualize 3-D objects. Practice, either rotational or not, consisted of visualizing 2- and 3-D objects generated by personal computer (PC)-based computer-assisted design software. Results indicated that participants in the rotation treatment group performed significantly better than those in either the nonrotation or control group on measures of spatial ability and 3-D visualization ability. Both treatment groups performed significantly better than the control group on measures of metacognition, effort, and worry. These results support a conclusion that spatial ability can be improved through practice that allows the learner to see the relationship between the 2-D and 3-D features of objects.

  10. NALDA (Naval Aviation Logistics Data Analysis) CAI (computer aided instruction)

    SciTech Connect

    Handler, B.H. ); France, P.A.; Frey, S.C.; Gaubas, N.F.; Hyland, K.J.; Lindsey, A.M.; Manley, D.O. ); Hunnum, W.H. ); Smith, D.L. )

    1990-07-01

    Data Systems Engineering Organization (DSEO) personnel developed a prototype computer aided instruction CAI system for the Naval Aviation Logistics Data Analysis (NALDA) system. The objective of this project was to provide a CAI prototype that could be used as an enhancement to existing NALDA training. The CAI prototype project was performed in phases. The task undertaken in Phase I was to analyze the problem and the alternative solutions and to develop a set of recommendations on how best to proceed. The findings from Phase I are documented in Recommended CAI Approach for the NALDA System (Duncan et al., 1987). In Phase II, a structured design and specifications were developed, and a prototype CAI system was created. A report, NALDA CAI Prototype: Phase II Final Report, was written to record the findings and results of Phase II. NALDA CAI: Recommendations for an Advanced Instructional Model, is comprised of related papers encompassing research on computer aided instruction CAI, newly developing training technologies, instructional systems development, and an Advanced Instructional Model. These topics were selected because of their relevancy to the CAI needs of NALDA. These papers provide general background information on various aspects of CAI and give a broad overview of new technologies and their impact on the future design and development of training programs. The paper within have been index separately elsewhere.

  11. Computer-aided design, synthesis, and biological evaluation of new indole-2-carboxamide derivatives as PI3Kα/EGFR inhibitors.

    PubMed

    Sweidan, Kamal; Sabbah, Dima A; Bardaweel, Sanaa; Dush, Khadeja Abu; Sheikha, Ghassan Abu; Mubarak, Mohammad S

    2016-06-01

    Structure-based drug design and molecular modeling were employed to identify a new series of indole-2-carboxamides as potential anticancer agents. These compounds were synthesized and characterized with the aid of several spectroscopic techniques, such as FT-IR, NMR, and mass spectrometry as well as by elemental analysis. Molecular docking studies confirmed that the newly synthesized compounds accommodate PI3Kα and EGFR kinase catalytic sites and form H-bonding with the key binding residues. The antitumor activity of these new compounds against an array of cancer cell lines (human colon carcinoma (HCT116), leukemia (K562), and breast cancer (MDA231) was evaluated. Results revealed that these compounds were selective against the kinase domain, and none of them showed any inhibitory activity against K562. In addition, results showed that compound 13 exhibited high potency in HCT116 and MDA231 with IC50 values of 19 and 15μM, respectively. Our findings recommend that further optimization of this series would be beneficial for colon and breast cancer treatment. PMID:27084677

  12. Computer aided measurement of biomechanical characteristics of cadaverous lumbar spines

    NASA Astrophysics Data System (ADS)

    Bartoněk, Luděk; Keprt, Jiří; Charamza, Jiří; Hrabálek, Lumír

    2004-09-01

    Special computer-aided equipment was designed for measurement of biomechanical characteristics of lower part of the spine (L1-L5). When the stress is applied, it is necessary to observe the shift of the sample elements, together with measurement of the spine rigidity. This shift is determined with the help of circular targets fitted to the appropriate vertebra. The targets, illuminated by lamp or laser light, are monitored and their digitalized images are scanned by CCD camera is stored as computer media. The two dimensional Fourier transform of the digital optical signal is obtained by the fast Fourier transform algorithm. The period and direction of the interference fringes determine the size and the direction of the sample shift.

  13. 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.

  14. Computer aided lytic bone metastasis detection using regular CT images

    NASA Astrophysics Data System (ADS)

    Yao, Jianhua; O'Connor, Stacy D.; Summers, Ronald

    2006-03-01

    This paper presents a computer aided detection system to find lytic bone metastases in the spine. The CAD system is designed to run on routine chest and/or abdominal CT exams (5mm slice thickness) obtained during a patient's evaluation for other indications. The system can therefore serve as a background procedure to detect bone metastases. The spine is first automatically extracted based on adaptive thresholding, morphological operation, and region growing. The spinal cord is then traced from thoracic spine to lumbar spine using a dynamic graph search to set up a local spine coordinate system. A watershed algorithm is then applied to detect potential lytic bone lesions. A set of 26 quantitative features (density, shape and location) are computed for each detection. After a filter on the features, Support Vector Machines (SVM) are used as classifiers to determine if a detection is a true lesion. The SVM was trained using ground truth segmentation manually defined by experts.

  15. Providing Formative Feedback From a Summative Computer-aided Assessment

    PubMed Central

    Sewell, Robert D. E.

    2007-01-01

    Objectives To examine the effectiveness of providing formative feedback for summative computer-aided assessment. Design Two groups of first-year undergraduate life science students in pharmacy and neuroscience who were studying an e-learning package in a common pharmacology module were presented with a computer-based summative assessment. A sheet with individualized feedback derived from each of the 5 results sections of the assessment was provided to each student. Students were asked via a questionnaire to evaluate the form and method of feedback. Assessment The students were able to reflect on their performance and use the feedback provided to guide their future study or revision. There was no significant difference between the responses from pharmacy and neuroscience students. Students' responses on the questionnaire indicated a generally positive reaction to this form of feedback. Conclusions Findings suggest that additional formative assessment conveyed by this style and method would be appreciated and valued by students. PMID:17533442

  16. Computational valve plate design

    NASA Astrophysics Data System (ADS)

    Kalbfleisch, Paul

    Axial piston machines are widely used in many industries for their designs compactness, flexibility in power transfer, variable flow rate, and high efficiencies as compared to their manufacturing costs. One important component of all axial piston machines that is a very influential on the performance of the unit is the valve plate. The aim of this research is to develop a design methodology that is general enough to design all types of valve plates and the simple enough not to require advanced technical knowledge from the user. A new style of valve plate designs has been developed that comprehensively considers all previous design techniques and does not require significant changes to the manufacturing processes of valve plates. The design methodology utilizes a previously developed accurate computer model of the physical phenomenon. This allows the precise optimization of the valve plate design through the use of simulations rather than expensive trial and error processes. The design of the valve plate is clarified into the form of an optimization problem. This formulation into an optimization problem has motivated the selection of an optimization algorithm that satisfies the requirements of the design. The proposed design methodology was successfully tested in a case study in the shown to be very successful in improving required performance of the valve plate design.

  17. Computer-aided marginal artery detection on computed tomographic colonography

    NASA Astrophysics Data System (ADS)

    Wei, Zhuoshi; Yao, Jianhua; Wang, Shijun; Liu, Jiamin; Summers, Ronald M.

    2012-03-01

    Computed tomographic colonography (CTC) is a minimally invasive technique for colonic polyps and cancer screening. The marginal artery of the colon, also known as the marginal artery of Drummond, is the blood vessel that connects the inferior mesenteric artery with the superior mesenteric artery. The marginal artery runs parallel to the colon for its entire length, providing the blood supply to the colon. Detecting the marginal artery may benefit computer-aided detection (CAD) of colonic polyp. It can be used to identify teniae coli based on their anatomic spatial relationship. It can also serve as an alternative marker for colon localization, in case of colon collapse and inability to directly compute the endoluminal centerline. This paper proposes an automatic method for marginal artery detection on CTC. To the best of our knowledge, this is the first work presented for this purpose. Our method includes two stages. The first stage extracts the blood vessels in the abdominal region. The eigenvalue of Hessian matrix is used to detect line-like structures in the images. The second stage is to reduce the false positives in the first step. We used two different masks to exclude the false positive vessel regions. One is a dilated colon mask which is obtained by colon segmentation. The other is an eroded visceral fat mask which is obtained by fat segmentation in the abdominal region. We tested our method on a CTC dataset with 6 cases. Using ratio-of-overlap with manual labeling of the marginal artery as the standard-of-reference, our method yielded true positive, false positive and false negative fractions of 89%, 33%, 11%, respectively.

  18. Computer-Aided Design of Orally Bioavailable Pyrrolidine Carboxamide Inhibitors of Enoyl-Acyl Carrier Protein Reductase of Mycobacterium tuberculosis with Favorable Pharmacokinetic Profiles.

    PubMed

    Kouassi, Affiba Florance; Kone, Mawa; Keita, Melalie; Esmel, Akori; Megnassan, Eugene; N'Guessan, Yao Thomas; Frecer, Vladimir; Miertus, Stanislav

    2015-01-01

    We have carried out a computational structure-based design of new potent pyrrolidine carboxamide (PCAMs) inhibitors of enoyl-acyl carrier protein reductase (InhA) of Mycobacterium tuberculosis (MTb). Three-dimensional (3D) models of InhA-PCAMx complexes were prepared by in situ modification of the crystal structure of InhA-PCAM1 (Protein Data Bank (PDB) entry code: 4U0J), the reference compound of a training set of 20 PCAMs with known experimental inhibitory potencies (IC50(exp)). First, we built a gas phase quantitative structure-activity relationships (QSAR) model, linearly correlating the computed enthalpy of the InhA-PCAM complex formation and the IC50(exp). Further, taking into account the solvent effect and loss of inhibitor entropy upon enzyme binding led to a QSAR model with a superior linear correlation between computed Gibbs free energies (ΔΔGcom) of InhA-PCAM complex formation and IC50(exp) (pIC50(exp) = -0.1552·ΔΔGcom + 5.0448, R² = 0.94), which was further validated with a 3D-QSAR pharmacophore model generation (PH4). Structural information from the models guided us in designing of a virtual combinatorial library (VL) of more than 17 million PCAMs. The VL was adsorption, distribution, metabolism and excretion (ADME) focused and reduced down to 1.6 million drug like orally bioavailable analogues and PH4 in silico screened to identify new potent PCAMs with predicted IC50(pre) reaching up to 5 nM. Combining molecular modeling and PH4 in silico screening of the VL resulted in the proposed novel potent antituberculotic agent candidates with favorable pharmacokinetic profiles. PMID:26703572

  19. Computer-Aided Design of Orally Bioavailable Pyrrolidine Carboxamide Inhibitors of Enoyl-Acyl Carrier Protein Reductase of Mycobacterium tuberculosis with Favorable Pharmacokinetic Profiles

    PubMed Central

    Kouassi, Affiba Florance; Kone, Mawa; Keita, Melalie; Esmel, Akori; Megnassan, Eugene; N’Guessan, Yao Thomas; Frecer, Vladimir; Miertus, Stanislav

    2015-01-01

    We have carried out a computational structure-based design of new potent pyrrolidine carboxamide (PCAMs) inhibitors of enoyl-acyl carrier protein reductase (InhA) of Mycobacterium tuberculosis (MTb). Three-dimensional (3D) models of InhA-PCAMx complexes were prepared by in situ modification of the crystal structure of InhA-PCAM1 (Protein Data Bank (PDB) entry code: 4U0J), the reference compound of a training set of 20 PCAMs with known experimental inhibitory potencies (IC50exp). First, we built a gas phase quantitative structure-activity relationships (QSAR) model, linearly correlating the computed enthalpy of the InhA-PCAM complex formation and the IC50exp. Further, taking into account the solvent effect and loss of inhibitor entropy upon enzyme binding led to a QSAR model with a superior linear correlation between computed Gibbs free energies (ΔΔGcom) of InhA-PCAM complex formation and IC50exp (pIC50exp = −0.1552·ΔΔGcom + 5.0448, R2 = 0.94), which was further validated with a 3D-QSAR pharmacophore model generation (PH4). Structural information from the models guided us in designing of a virtual combinatorial library (VL) of more than 17 million PCAMs. The VL was adsorption, distribution, metabolism and excretion (ADME) focused and reduced down to 1.6 million drug like orally bioavailable analogues and PH4 in silico screened to identify new potent PCAMs with predicted IC50pre reaching up to 5 nM. Combining molecular modeling and PH4 in silico screening of the VL resulted in the proposed novel potent antituberculotic agent candidates with favorable pharmacokinetic profiles. PMID:26703572

  20. Progress of the Computer-Aided Engineering of Electric Drive Vehicle Batteries (CAEBAT) (Presentation)

    SciTech Connect

    Pesaran, A. A.; Han, T.; Hartridge, S.; Shaffer, C.; Kim, G. H.; Pannala, S.

    2013-06-01

    This presentation, Progress of Computer-Aided Engineering of Electric Drive Vehicle Batteries (CAEBAT) is about simulation and computer-aided engineering (CAE) tools that are widely used to speed up the research and development cycle and reduce the number of build-and-break steps, particularly in the automotive industry. Realizing this, DOE?s Vehicle Technologies Program initiated the CAEBAT project in April 2010 to develop a suite of software tools for designing batteries.

  1. Software for computer-aided receiver operating characteristic (ROC) analysis

    NASA Astrophysics Data System (ADS)

    Engel, John R.; Craine, Eric R.

    1994-04-01

    We are currently developing an easy-to-use, microcomputer-based software application to help researchers perform ROC studies. The software will have facilities for aiding the researcher in all phases of an ROC study, including experiment design, setting up and conducting test sessions, analyzing results and generating reports. The initial version of the software, named 'ROC Assistant', operates on Macintosh computers and enables the user to enter a case list, run test sessions and produce an ROC curve. We are in the process of developing enhanced versions which will incorporate functions for statistical analysis, experimental design and online help. In this paper we discuss the ROC methodology upon which the software is based as well as our software development effort to date.

  2. COMPUTER-AIDED DATA ACQUISITION FOR COMBUSTION EXPERIMENTS

    EPA Science Inventory

    The article describes the use of computer-aided data acquisition techniques to aid the research program of the Combustion Research Branch (CRB) of the U.S. EPA's Air and Energy Engineering Research Laboratory (AEERL) in Research Triangle Park, NC, in particular on CRB's bench-sca...

  3. Computer-Aided Energy Analysis for Buildings: An Assessment of Its Value for Students of Technology and Architecture.

    ERIC Educational Resources Information Center

    Ridenour, Steven

    1981-01-01

    Demonstrates that computer aided energy analysis improves students' (N=29) comprehension and prediction accuracy of energy consumption in buildings and confirms that a reasonably accurate building energy analysis computer program can be designed for student users. (Author/SK)

  4. Computer Aided Lip Reading Training Tool

    ERIC Educational Resources Information Center

    Sarmasik, Gamze; Dalkilic, Gokhan; Kut, Alp; Cebi, Yalcin; Serbetcioglu, Bulent

    2007-01-01

    Worldwide auditory-verbal education is becoming widespread for deaf children. But many prelingually, late-diagnosed deaf children and adults may utilize neither hearing aids nor cochlear implants and needed the support of lip-reading. Therefore, lip-reading skill remains to be important for oral education programmes of hearing impaired. The…

  5. Domain specific software design for decision aiding

    NASA Technical Reports Server (NTRS)

    Keller, Kirby; Stanley, Kevin

    1992-01-01

    McDonnell Aircraft Company (MCAIR) is involved in many large multi-discipline design and development efforts of tactical aircraft. These involve a number of design disciplines that must be coordinated to produce an integrated design and a successful product. Our interpretation of a domain specific software design (DSSD) is that of a representation or framework that is specialized to support a limited problem domain. A DSSD is an abstract software design that is shaped by the problem characteristics. This parallels the theme of object-oriented analysis and design of letting the problem model directly drive the design. The DSSD concept extends the notion of software reusability to include representations or frameworks. It supports the entire software life cycle and specifically leads to improved prototyping capability, supports system integration, and promotes reuse of software designs and supporting frameworks. The example presented in this paper is the task network architecture or design which was developed for the MCAIR Pilot's Associate program. The task network concept supported both module development and system integration within the domain of operator decision aiding. It is presented as an instance where a software design exhibited many of the attributes associated with DSSD concept.

  6. The digital hearing aid, wearable computing, and electrophysiological response.

    PubMed

    Doyle, T E; Kucerovsky, Z; Greason, W D

    2002-01-01

    Presbycusis is the most common form of hearing loss caused by aging and long-term exposure to sound energy. This type of ailment decreases the ear's ability to perceive high frequencies and localize sound, thus making comprehension more difficult. To compensate for this loss, the choice of a digital hearing aid has become more common. However, most digital hearing aids do little more that their analogue predecessor's by providing a single, fixed hearing response. Such a fixed response is not suitable for all of a user's auditory environments and typically causes a more rapid loss of hearing. Significant advancement in processing power and reduction in size of computing hardware has produced increasingly more powerful, more portable, and more personal computing devices. These advances have spurred research and development of wearable computing devices towards integrating both man and machine. By definition, the digital hearing aid is a wearable computing device. The development of a digital hearing aid with increased onboard processing that is aware of its owner's electrophysiological and auditory environments is an obvious progression. This awareness will give the hearing aid the ability to autonomously modify its own parameters to improve audibility and comprehension. Electrophysiological signals can be classified as naturally occurring or voluntarily controlled. Employing these signals will allow the hearing aid to adapt to its owner's external and internal stimuli. Research and initial experiments into the monitoring and use of electrophysiological response for the control of the digital hearing aid shall be presented.

  7. Computer aided lung cancer diagnosis with deep learning algorithms

    NASA Astrophysics Data System (ADS)

    Sun, Wenqing; Zheng, Bin; Qian, Wei

    2016-03-01

    Deep learning is considered as a popular and powerful method in pattern recognition and classification. However, there are not many deep structured applications used in medical imaging diagnosis area, because large dataset is not always available for medical images. In this study we tested the feasibility of using deep learning algorithms for lung cancer diagnosis with the cases from Lung Image Database Consortium (LIDC) database. The nodules on each computed tomography (CT) slice were segmented according to marks provided by the radiologists. After down sampling and rotating we acquired 174412 samples with 52 by 52 pixel each and the corresponding truth files. Three deep learning algorithms were designed and implemented, including Convolutional Neural Network (CNN), Deep Belief Networks (DBNs), Stacked Denoising Autoencoder (SDAE). To compare the performance of deep learning algorithms with traditional computer aided diagnosis (CADx) system, we designed a scheme with 28 image features and support vector machine. The accuracies of CNN, DBNs, and SDAE are 0.7976, 0.8119, and 0.7929, respectively; the accuracy of our designed traditional CADx is 0.7940, which is slightly lower than CNN and DBNs. We also noticed that the mislabeled nodules using DBNs are 4% larger than using traditional CADx, this might be resulting from down sampling process lost some size information of the nodules.

  8. Diagnostic Accuracy of Digital Screening Mammography with and without Computer-aided Detection

    PubMed Central

    Lehman, Constance D.; Wellman, Robert D.; Buist, Diana S.M.; Kerlikowske, Karla; Tosteson, Anna N. A.; Miglioretti, Diana L.

    2016-01-01

    Importance After the Food and Drug Administration (FDA) approved computer-aided detection (CAD) for mammography in 1998, and Centers for Medicare and Medicaid Services (CMS) provided increased payment in 2002, CAD technology disseminated rapidly. Despite sparse evidence that CAD improves accuracy of mammographic interpretations, and costs over $400 million dollars a year, CAD is currently used for the majority of screening mammograms in the U.S. Objective To measure performance of digital screening mammography with and without computer-aided detection in U.S. community practice. Design, Setting and Participants We compared the accuracy of digital screening mammography interpreted with (N=495,818) vs. without (N=129,807) computer-aided detection from 2003 through 2009 in 323,973 women. Mammograms were interpreted by 271 radiologists from 66 facilities in the Breast Cancer Surveillance Consortium. Linkage with tumor registries identified 3,159 breast cancers in 323,973 women within one year of the screening. Main Outcomes and Measures Mammography performance (sensitivity, specificity, and screen detected and interval cancers per 1,000 women) was modeled using logistic regression with radiologist-specific random effects to account for correlation among examinations interpreted by the same radiologist, adjusting for patient age, race/ethnicity, time since prior mammogram, exam year, and registry. Conditional logistic regression was used to compare performance among 107 radiologists who interpreted mammograms both with and without computer-aided detection. Results Screening performance was not improved with computer-aided detection on any metric assessed. Mammography sensitivity was 85.3% (95% confidence interval [CI]=83.6–86.9) with and 87.3% (95% CI 84.5–89.7) without computer-aided detection. Specificity was 91.6% (95% CI=91.0–92.2) with and 91.4% (95% CI=90.6–92.0) without computer-aided detection. There was no difference in cancer detection rate (4

  9. Designing Artificial Enzymes by Intuition and Computation

    PubMed Central

    Nanda, Vikas; Koder, Ronald L.

    2012-01-01

    The rational design of artificial enzymes either by applying physio-chemical intuition of protein structure and function or with the aid of computation methods is a promising area of research with the potential to tremendously impact medicine, industrial chemistry and energy production. Designed proteins also provide a powerful platform for dissecting enzyme mechanisms of natural systems. Artificial enzymes have come a long way, from simple α-helical peptide catalysts to proteins that facilitate multi-step chemical reactions designed by state-of-the-art computational methods. Looking forward, we examine strategies employed by natural enzymes which could be used to improve the speed and selectivity of artificial catalysts. PMID:21124375

  10. Computer-aided design of AD 2 X 2 intermetallics with a ThCr2Si2-type of crystal structure

    NASA Astrophysics Data System (ADS)

    Kiselyova, N. N.; Sen'ko, O. V.; Kropotov, D. A.; Dokukin, A. A.

    2012-07-01

    Several hundred new AD 2 X 2 ( A and D are various elements; X = B, Al, Si, P, Ga, Ge, As, Sn, Sb) compounds are computer designed, and the types of their crystal structures under normal conditions are predicted. A special software package is used for the calculations; it includes a set of databases on the properties of inorganic substances and materials and a system for an analysis of these data, which is based on precedent pattern recognition methods. Only data on the properties of the elements entering into the compound compositions are used to predict unknown compounds. The parameters of elements in positions A and D (i.e., the Mendeleev-Pettifor numbers, the pseudopotential radii, and their algebraic functions) are found to mainly determine the possibility of formation of AD 2 X 2 compounds and the type of their crystal structures. New compounds of AD 2B2, AD 2Ga2, and AD 2Sn2 compositions are predicted for the first time.

  11. Computer-aided optimization of phosphinic inhibitors of bacterial ureases.

    PubMed

    Vassiliou, Stamatia; Kosikowska, Paulina; Grabowiecka, Agnieszka; Yiotakis, Athanasios; Kafarski, Paweł; Berlicki, Lukasz

    2010-08-12

    Urease inhibitors can be considered as a tool to control the damaging effect of ureolytic bacteria infections in humans which occur commonly in the developed countries. Computer-aided optimization of the aminomethylphosphinate structures by modifying both their N- and P-termini led to the invention of a novel group of inhibitors of bacterial ureases. Introduction of P-hydroxymethyl group into the molecule resulted in considerable increase of the inhibitory activity against enzymes purified from Bacillus pasteurii and Proteus vulgaris as compared with their P-methyl counterparts described previously. The designed compounds represent a competitive reversible class of urease inhibitors. The most potent, N-methyl-aminomethyl-P-hydroxymethylphosphinic acid, displayed K(i) = 360 nM against P. vulgaris enzyme. PMID:20684601

  12. Computer-Aided Instruction in Automated Instrumentation.

    ERIC Educational Resources Information Center

    Stephenson, David T.

    1986-01-01

    Discusses functions of automated instrumentation systems, i.e., systems which combine electrical measuring instruments and a controlling computer to measure responses of a unit under test. The computer-assisted tutorial then described is programmed for use on such a system--a modern microwave spectrum analyzer--to introduce engineering students to…

  13. Cheap computer aids for medical photography departments.

    PubMed

    Jankowski, R A

    1989-01-01

    Most departments now use computers to assist in administration. Choice of hardware and software is very much dependent upon the complexity of the tasks and also on the amount of money available to purchase such equipment. This paper gives an insight into how a low cost computer system is successfully introduced into a department and is proving good value for money.

  14. Computer Aided Instruction in Teaching Thematic Mapping.

    ERIC Educational Resources Information Center

    Baumann, Paul R.

    A newly developed instructional system for introductory college geography links the computer with the geographer's most traditional and essential tool--the thematic map. The use of the computer overcomes the logistical and mechanical problems associated with the teaching of thematic mapping to large groups and helps the students to focus upon the…

  15. Computer-Aided Personalized System of Instruction: A Program Evaluation.

    ERIC Educational Resources Information Center

    Pear, Joseph J.; Novak, Mark

    1996-01-01

    Presents an evaluation of a computer-aided personalized system of instruction program in two undergraduate psychology courses. The computer presented short essay tests and arranged for students who had completed various assignments satisfactorily to help evaluate other students' mastery of those assignments. Student response generally was…

  16. Helping Alleviate Statistical Anxiety with Computer Aided Statistical Classes

    ERIC Educational Resources Information Center

    Stickels, John W.; Dobbs, Rhonda R.

    2007-01-01

    This study, Helping Alleviate Statistical Anxiety with Computer Aided Statistics Classes, investigated whether undergraduate students' anxiety about statistics changed when statistics is taught using computers compared to the traditional method. Two groups of students were questioned concerning their anxiety about statistics. One group was taught…

  17. Multidisciplinary Expert-aided Analysis and Design (MEAD)

    NASA Technical Reports Server (NTRS)

    Hummel, Thomas C.; Taylor, James

    1989-01-01

    The MEAD Computer Program (MCP) is being developed under the Multidisciplinary Expert-Aided Analysis and Design (MEAD) Project as a CAD environment in which integrated flight, propulsion, and structural control systems can be designed and analyzed. The MCP has several embedded computer-aided control engineering (CACE) packages, a user interface (UI), a supervisor, a data-base manager (DBM), and an expert system (ES). The supervisor monitors and coordinates the operation of the CACE packages, the DBM; the ES, and the UI. The DBM tracks the control design process. Models created or installed by the MCP are tracked by date and version, and results are associated with the specific model version with which they were generated. The ES is used to relieve the control engineer from tedious and cumbersome tasks in the iterative design process. The UI provides the capability for a novice as well as an expert to utilize the MCP easily and effectively. The MCP version 2(MCP-2.0) is fully developed for flight control system design and analysis. Propulsion system modeling, analysis, and simulation is also supported; the same is true for structural models represented in state-space form. The ultimate goal is to cover the integration of flight, propulsion, and structural control engineering, including all discipline-specific functionality and interfaces. The current MCP-2.0 components and functionality are discussed.

  18. Computer-aided analysis of a Superfund site

    SciTech Connect

    Qualheim, B.J. )

    1990-05-01

    The groundwater investigation at the Lawrence Livermore National Laboratory was initiated in 1983 after perchloroethylene (PCE) and trichloroethylene (TCE) were detected in the groundwater. Since that time, more than 300 monitor wells have been completed, logged, sampled, and hydraulically tested. In 1987, the Livermore site was placed on the Environmental Protection Agency's National Priority List (Superfund). The Livermore valley is relatively flat, underlain by a complex alluvial sedimentary basin drained by two intermittent streams. The subsurface consists of unconsolidated sand, gravel, silt, and clay with multiple water-bearing zones of relatively high permeability. The hydrogeologic system is characterized as leaky, with horizontal hydraulic communication of up to 800 ft and vertical communication between aquifers of up to 50 ft. Computer-based analysis of the site stratigraphy was used to analyze and characterize the subsurface. The authors used a computer-aided design and drafting (CADD) system to create two-dimensional slices of the subsurface. The slice program takes a subsurface slice at any specified depositional gradient and at any slice thickness. A slice displays the lithology type, unit thickness, depth of slice, and chemical analyses for volatile organic compounds (VOCs). The lateral continuity of subsurface channels was mapped for each depth slice. By stacking these maps, the authors interpreted a pseudo-three-dimensional representation of probably pathways for VOC movement in the subsurface. An enhanced computer graphics system was also used to map the movement of VOCs in the subsurface.

  19. Computer-Aided Collaborative Music Instruction.

    ERIC Educational Resources Information Center

    Hoffmann, James A.

    1991-01-01

    At the New England Conservatory of Music, computer-assisted instruction is used not only to teach harmony through collaborative learning and aural feedback, but also to bring the roles of composer, performer, and audience closer together. (SK)

  20. Computer-Aided Sensor Development Focused on Security Issues

    PubMed Central

    Bialas, Andrzej

    2016-01-01

    The paper examines intelligent sensor and sensor system development according to the Common Criteria methodology, which is the basic security assurance methodology for IT products and systems. The paper presents how the development process can be supported by software tools, design patterns and knowledge engineering. The automation of this process brings cost-, quality-, and time-related advantages, because the most difficult and most laborious activities are software-supported and the design reusability is growing. The paper includes a short introduction to the Common Criteria methodology and its sensor-related applications. In the experimental section the computer-supported and patterns-based IT security development process is presented using the example of an intelligent methane detection sensor. This process is supported by an ontology-based tool for security modeling and analyses. The verified and justified models are transferred straight to the security target specification representing security requirements for the IT product. The novelty of the paper is to provide a patterns-based and computer-aided methodology for the sensors development with a view to achieving their IT security assurance. The paper summarizes the validation experiment focused on this methodology adapted for the sensors system development, and presents directions of future research. PMID:27240360

  1. Computer-Aided Sensor Development Focused on Security Issues.

    PubMed

    Bialas, Andrzej

    2016-01-01

    The paper examines intelligent sensor and sensor system development according to the Common Criteria methodology, which is the basic security assurance methodology for IT products and systems. The paper presents how the development process can be supported by software tools, design patterns and knowledge engineering. The automation of this process brings cost-, quality-, and time-related advantages, because the most difficult and most laborious activities are software-supported and the design reusability is growing. The paper includes a short introduction to the Common Criteria methodology and its sensor-related applications. In the experimental section the computer-supported and patterns-based IT security development process is presented using the example of an intelligent methane detection sensor. This process is supported by an ontology-based tool for security modeling and analyses. The verified and justified models are transferred straight to the security target specification representing security requirements for the IT product. The novelty of the paper is to provide a patterns-based and computer-aided methodology for the sensors development with a view to achieving their IT security assurance. The paper summarizes the validation experiment focused on this methodology adapted for the sensors system development, and presents directions of future research. PMID:27240360

  2. Computer-Aided Sensor Development Focused on Security Issues.

    PubMed

    Bialas, Andrzej

    2016-05-26

    The paper examines intelligent sensor and sensor system development according to the Common Criteria methodology, which is the basic security assurance methodology for IT products and systems. The paper presents how the development process can be supported by software tools, design patterns and knowledge engineering. The automation of this process brings cost-, quality-, and time-related advantages, because the most difficult and most laborious activities are software-supported and the design reusability is growing. The paper includes a short introduction to the Common Criteria methodology and its sensor-related applications. In the experimental section the computer-supported and patterns-based IT security development process is presented using the example of an intelligent methane detection sensor. This process is supported by an ontology-based tool for security modeling and analyses. The verified and justified models are transferred straight to the security target specification representing security requirements for the IT product. The novelty of the paper is to provide a patterns-based and computer-aided methodology for the sensors development with a view to achieving their IT security assurance. The paper summarizes the validation experiment focused on this methodology adapted for the sensors system development, and presents directions of future research.

  3. Program Aids Analysis And Optimization Of Design

    NASA Technical Reports Server (NTRS)

    Rogers, James L., Jr.; Lamarsh, William J., II

    1994-01-01

    NETS/ PROSSS (NETS Coupled With Programming System for Structural Synthesis) computer program developed to provide system for combining NETS (MSC-21588), neural-network application program and CONMIN (Constrained Function Minimization, ARC-10836), optimization program. Enables user to reach nearly optimal design. Design then used as starting point in normal optimization process, possibly enabling user to converge to optimal solution in significantly fewer iterations. NEWT/PROSSS written in C language and FORTRAN 77.

  4. The practical computer in design

    SciTech Connect

    Schuman, J.; Ward, G.

    1990-07-01

    Electronic information processing is becoming a necessity in today's complex design environment, but what is an appropriate role for the computer in the design process Computation should be applied throughout all design phases, but practicing designers today rarely use computers beyond simple word processing and drafting tasks. While many design tasks are poorly matched to the computer, other pragmatic and productive avenues remain unexploited. We discuss the need to recognize which elements of the design process are most suited to computer assistance. The authors define a role for the computer as an objective assistant to the designer, and discuss practical approaches in two application areas for computers in design: design simulation and resource information management.

  5. Computational-aided design of molecularly imprinted polymer for selective extraction of methadone from plasma and saliva and determination by gas chromatography.

    PubMed

    Ahmadi, F; Rezaei, H; Tahvilian, R

    2012-12-28

    The main objective of this research was computational designing of an imprinted polymer for selective solid phase extraction (SPE) of methadone from plasma and saliva samples analyzed by gas chromatography-flam ionization detector (GC-FID). The density functional theory (DFT) at B3LYP/6-31G+ (d, p) level and Gaussian 2003 package was used to calculate the interaction energy of template-monomers (ΔE). The effect of polymerization solvent was also studied using polarizable continuum model (PCM). It was shown that, methacrylic acid (MAA) gave the largest ΔE in acetonitrile as a polymerization solvent. To examine the validity of this approach, two MIP were synthesized for methadone as template molecule and methacrylic acid as functional monomer in acetonitrile (AN) and methanol (MeOH), respectively. The performance of each polymer was evaluated by using imprinting effect. As it is expected, the best results were obtained for the molecularly imprinted polymer (MIP) which was prepared in AN. For the optimized method, the linearity between responses (peak areas) and concentration of methadone in plasma and saliva samples were found over the range of 3.6-40,000 ng mL(-1) (R(2)=0.997) and 3.0-40,000 ng mL(-1) (R(2)=0.998), respectively. The limit of detection (LOD) and limit of quantification (LOQ) for methadone in plasma were calculated to be 2.45 and 3.6 ng mL(-1), respectively. The LOD and LOQ for methadone in saliva were 2.14 and 3.0 ng mL(-1), respectively. The relative standard deviation (RSD; n=4) for plasma samples containing 10, 100, 500, 1000 ng mL(-1)of methadone were 5.98, 5.78, 5.52, 4.78, 4.74, and the RSD (n=4) for saliva sample containing 5, 20, 100, 1000 ng mL(-1) of methadone were 4.74, 5.1, 5.9, 5.6, respectively. PMID:23159198

  6. Computer-aided engineering of energy systems

    SciTech Connect

    Gaggioli, R.A.

    1986-01-01

    This book presents that papers given at a conference on computer calculations of the thermodynamics of energy systems. Topics considered at the conference included exergy saving, thermoeconomic cost, heat exchanger networks, integrated coal gasification-combined cycle power plants, computer graphics, second law analysis of diesel engines, cogenerating gas turbine plants, exergy analysis of heat transfer, water absorption heat pumps, the thermodynamics of wood combustion, second law efficiency and costing analysis of a combined power and desalination plant, and pressure-driven temperature separation in liquids.

  7. The Rationale for Computer-Aided Instruction.

    ERIC Educational Resources Information Center

    Clark, Robert Charles

    1983-01-01

    Some theoretical considerations for increased use of computer-assisted instruction (CAI) in legal education are compared with other teaching methods, empirical evidence of the method's effectiveness is discussed, and some of the activities involving CAI at Harvard Law School are outlined. (MSE)

  8. Computer Aided Instruction in Teaching Program Evaluation.

    ERIC Educational Resources Information Center

    Dowell, David A.; Binette, Holly A. Lizotte

    This paper reports the results of two semesters of experience using computer-assisted instruction (CAI) to teach topics in program evaluation to undergraduate and graduate psychology students at California State University, Long Beach. (The topics addressed are models of evaluation, evaluability assessment, needs assessment, experimental and…

  9. Computer-Assisted Instruction in Programming: AID.

    ERIC Educational Resources Information Center

    Friend, Jamesine; Atkinson, R. C.

    A computer-assisted course on programing, consisting of a set of 50 lessons, was developed for and is now being used by National Aeronautics and Space Administration (NASA) personnel. The course is intended for students at about the junior college level with no experience in mathematics beyond high school algebra and with no previous introduction…

  10. Computer-aided engineering annual report for calendar year 1989

    SciTech Connect

    Brockelsby, H.C. Jr.

    1990-03-01

    During calendar year 1989, EG G Idaho completed the initial procurement and implementation of a major new Computer-Aided Engineering (CAE) system. Seventy new workstations and associated engineering applications were installed over 100 personal computers (PCs) were integrated into the environment, and communications links to the IBM mainframes and the Cray supercomputer were established. The system achieves integration through sophisticated data communications and application interfaces that allow data sharing across the entire environment. Applications available on the system facilitate engineering relate to full three-dimensional (3-D) piping, heating/ventilating/air conditioning (HAVC), structural and steel design, solids modeling and analysis, desktop publishing, design and drafting, and include automated links to various analysis codes on the Cray supercomputer. The system also provides commonly used engineering tools such as spreadsheets, language compilers, terminal emulation, and file transfer facilities. Although difficult to quantify, recent information has shown that projected annual productivity improvement to the Idaho National Engineering Laboratory (INEL) will be in excess of $2,000,000. This improvement will be generated in a variety of areas including improvement in the efficiency of individual users, checkplot production, data management, file transfers, plotting. design-analysis interfaces, and the benefit of full 3-D design. Current plans call for a significant expansion of the CAE system in 1990 with continued expansion through 1993. Additional workstations, system software and utilities, networking facilities and applications software will be procured and implemented. More than one hundred people will receive training on the various application packages during 1990. Efforts to extend networking throughout the INEL will be continued. 2 refs.

  11. Visions of visualization aids - Design philosophy and observations

    NASA Technical Reports Server (NTRS)

    Ellis, Stephen R.

    1989-01-01

    Aids for the visualization of high-dimensional scientific or other data must be designed. Simply casting multidimensional data into a two-dimensional or three-dimensional spatial metaphor does not guarantee that the presentation will provide insight or a parsimonious description of phenomena implicit in the data. Useful visualization, in contrast to glitzy, high-tech, computer-graphics imagery, is generally based on preexisting theoretical beliefs concerning the underlying phenomena. These beliefs guide selection and formatting of the plotted variables. Visualization tools are useful for understanding naturally three-dimensional data bases such as those used by pilots or astronauts. Two examples of such aids for spatial maneuvering illustrate that informative geometric distortion may be introduced to assist visualization and that visualization of complex dynamics alone may not be adequate to provide the necessary insight into the underlying processes.

  12. PCACE-Personal-Computer-Aided Cabling Engineering

    NASA Technical Reports Server (NTRS)

    Billitti, Joseph W.

    1987-01-01

    PCACE computer program developed to provide inexpensive, interactive system for learning and using engineering approach to interconnection systems. Basically database system that stores information as files of individual connectors and handles wiring information in circuit groups stored as records. Directly emulates typical manual engineering methods of handling data, thus making interface between user and program very natural. Apple version written in P-Code Pascal and IBM PC version of PCACE written in TURBO Pascal 3.0

  13. Computer-aided protective system (CAPS)

    SciTech Connect

    Squire, R.K.

    1988-01-01

    A method of improving the security of materials in transit is described. The system provides a continuously monitored position location system for the transport vehicle, an internal computer-based geographic delimiter that makes continuous comparisons of actual positions with the preplanned routing and schedule, and a tamper detection/reaction system. The position comparison is utilized to institute preprogrammed reactive measures if the carrier is taken off course or schedule, penetrated, or otherwise interfered with. The geographic locater could be an independent internal platform or an external signal-dependent system utilizing GPS, Loran or similar source of geographic information; a small (micro) computer could provide adequate memory and computational capacity; the insurance of integrity of the system indicates the need for a tamper-proof container and built-in intrusion sensors. A variant of the system could provide real-time transmission of the vehicle position and condition to a central control point for; such transmission could be encrypted to preclude spoofing.

  14. Computer-aided simulation of piston and piston ring dynamics

    SciTech Connect

    Knoll, G.; Peeken, H.; Lechtape-Grueter, R.; Lang, J.

    1996-10-01

    A numerical computer simulation program was developed, aiding in finding optimum design parameters in the multibody-system piston, piston-rings, and cylinder with respect to optimum sealing, minimal friction, and minimum noise stimulation(impact impulse). In the simulation of piston secondary movement and piston ring motion, forces arising from the combustion process, subsonic/supersonic gas flow between the combustion chamber and the crank case, inertial forces and forces resulting from the hydrodynamic lubrication between cylinder liner and piston shaft and piston rings and between piston ring flanks and piston grooves are considered. In addition it is possible to account for effects of global, three-dimensional ring deformation as well as local piston deformation, roughness effects in lubricated contacts, and variable viscosity and variable oil supply. The governing differential equations for the pressure as well as the deformation are solved via finite element techniques, while initial value problems are solved by efficient implicit time integration schemes. The application of the developed computer code is presented in examples.

  15. Computer-aided mapping of brain tissue

    SciTech Connect

    Rogers, W.T.; Schwaber, J.S.

    1987-08-15

    A computer-microscope system is described for use in capturing accurate, quantitative schematic (map) information from anatomical tissue sections. The system provides a rapid and convenient environment for acquisition and analysis for complex structures spread over large 3-D regions of the tissue. As a consequence of the complexity and subtlety of tissue analysis, most of the data acquisition functions of the system involve tight coupling between the hardware and the microscopist to preserve access to human judgment and intelligence. The instrument profoundly affects the ease and accuracy of neurobiological data analysis, making it practical to address previously inaccessible problems. Examples of data analyzed using the system are shown.

  16. Computer-aided forensics: facial reconstruction.

    PubMed

    Turner, Wesley; Tu, Peter; Kelliher, Timothy; Brown, Rebecca

    2006-01-01

    The 3D reconstruction of facial features from skeletal remains is a key component to the identification of missing persons and victims of violent crime. A comprehensive Computed Tomography (CT) head-scan database is currently being collected which will enable a new approach to forensic facial reconstruction. Using this unique resource, we show how a face space can be tailored to a specific unknown, or questioned skull. A set of database derived estimates of the questioned face is constructed by first computing non-rigid transformations between the known head-scan skulls and the questioned skull followed by application of these transformations to the known head-scan faces. This effectively factors out influences due to skeletal variation. A tailored face space is formed by applying Principal Component Analysis (PCA) to this ensemble of estimates of the questioned face. Thus, the face space is a direct approximation of correlated soft tissue variance indicative of the population. Ours is the first mathematical representation of the face continuum associated with a given skull. Embedded in this space resides the elements needed for recognition.

  17. Single photon emission computed tomography in AIDS dementia complex

    SciTech Connect

    Pohl, P.; Vogl, G.; Fill, H.; Roessler, H.Z.; Zangerle, R.; Gerstenbrand, F.

    1988-08-01

    Single photon emission computed tomography (SPECT) studies were performed in AIDS dementia complex using IMP in 12 patients (and HM-PAO in four of these same patients). In all patients, SPECT revealed either multiple or focal uptake defects, the latter corresponding with focal signs or symptoms in all but one case. Computerized tomography showed a diffuse cerebral atrophy in eight of 12 patients, magnetic resonance imaging exhibited changes like atrophy and/or leukoencephalopathy in two of five cases. Our data indicate that both disturbance of cerebral amine metabolism and alteration of local perfusion share in the pathogenesis of AIDS dementia complex. SPECT is an important aid in the diagnosis of AIDS dementia complex and contributes to the understanding of the pathophysiological mechanisms of this disorder.

  18. [OCAS (Optic and computer aided surgery)].

    PubMed

    Rheims, D M; Pflug, L

    1994-12-01

    OCAS is a new, original tool for the diagnosis of dismorphies, both in its conception (digitalisation of a moiré pattern on the body) and in its applications (predominantly surgical, for legal medicine and didactic purposes). By means of this new 3D method of measurement by digitalised moiré, the forms of the body in general, and those of the face in particular, can be studied and quantified with a high degree of accuracy. This precision in the geometrical analysis of its forms is achieved by combining the very latest developments in optics and computer technology. The authors present the current state of their research in the 3D synthesis and manipulation of the human image. PMID:7661561

  19. Computers in design construction and operation of automobiles

    SciTech Connect

    Murthy, T.K.; Brebbia, C.A.

    1987-01-01

    The advantages of computer-aided systems in the automotive industry are now widely recognised. Computers are being used from initial conceptual design and feasibility study to the actual construction and ultimate operation of the cars on the road. In the field of car body design, for example, the use of computers is replacing the traditional, if more expensive, testing methods such as in a wind tunnel, due to the extensive development of numerical computational methods. The papers contained in this book are related to the use of computers in such diverse applications as solid modelling, computational fluid dynamics, computer simulation, engine dynamics and other topics in design.

  20. Computer design code for conical ribbon parachutes

    SciTech Connect

    Waye, D.E.

    1986-01-01

    An interactive computer design code has been developed to aid in the design of conical ribbon parachutes. The program is written to include single conical and polyconical parachute designs. The code determines the pattern length, vent diameter, radial length, ribbon top and bottom lengths, and geometric local and average porosity for the designer with inputs of constructed diameter, ribbon widths, ribbon spacings, radial width, and number of gores. The gores are designed with one mini-radial in the center with an option for the addition of two outer mini-radials. The output provides all of the dimensions necessary for the construction of the parachute. These results could also be used as input into other computer codes used to predict parachute loads.

  1. Brain, a Computer Program to Aid Creative Thinking.

    ERIC Educational Resources Information Center

    Proctor, Tony

    1991-01-01

    This article describes 2 experiments conducted with a computer-aided problem-solving tool called BRAIN, involving 30 adults of varying backgrounds and 15 organizational executives. The BRAIN program encourages users to discover partially and fully formulated insights, through iterative generation of word lists and meaningful statements. Eighty…

  2. Computer Assisted Financial Aid Disbursement and Loan Collection

    ERIC Educational Resources Information Center

    Miller, Larry K.

    1975-01-01

    Describes the computer assisted system in use at Washington State University. It controls and reports funds requested by students, offered to students, and disbursed to students, writes financial aid checks, prepares fiscal year-end statements and performs loan collection processes according to federal government regulations, and provides internal…

  3. Preparing Students for Computer Aided Drafting (CAD). A Conceptual Approach.

    ERIC Educational Resources Information Center

    Putnam, A. R.; Duelm, Brian

    This presentation outlines guidelines for developing and implementing an introductory course in computer-aided drafting (CAD) that is geared toward secondary-level students. The first section of the paper, which deals with content identification and selection, includes lists of mechanical drawing and CAD competencies and a list of rationales for…

  4. PROGRAMMING EXERCISES FOR COMPUTER AIDED DRAFTING (TITLE SUPPLIED).

    ERIC Educational Resources Information Center

    Miami-Dade Junior Coll., FL.

    REFERENCE MATERIAL AND PROGRAMING EXERCISES USED FOR THE COMPUTER AIDED DRAFTING SUMMER INSTITUTE AT MIAMI-DADE JUNIOR COLLEGE, JULY 10-28, 1967, ARE PRESENTED. THE EXERCISES, TO BE PROGRAMED FOR EXECUTION ON THE IBM SYSTEM 1620 WITH AN ON-LINE 1627 PLOTTER, PROVIDE A MEDIUM FOR COVERING AND ENFORCING THE SUBJECT MATERIAL. ALSO INCLUDED ARE (1)…

  5. Computer-Aided Drafting. Education for Technology Employment.

    ERIC Educational Resources Information Center

    Northern Illinois Univ., De Kalb. Dept. of Technology.

    This computer-aided drafting (CAD) curriculum was developed to provide drafting instructors in Illinois with a useful guide for relating an important new technological advance to the vocational classroom. The competency-based learning activity guides are written to be used with any CAD system being used at the secondary and postsecondary levels.…

  6. A Model for Intelligent Computer-Aided Education Systems.

    ERIC Educational Resources Information Center

    Du Plessis, Johan P.; And Others

    1995-01-01

    Proposes a model for intelligent computer-aided education systems that is based on cooperative learning, constructive problem-solving, object-oriented programming, interactive user interfaces, and expert system techniques. Future research is discussed, and a prototype for teaching mathematics to 10- to 12-year-old students is appended. (LRW)

  7. Computer-Aided Communication Satellite System Analysis and Optimization.

    ERIC Educational Resources Information Center

    Stagl, Thomas W.; And Others

    Various published computer programs for fixed/broadcast communication satellite system synthesis and optimization are discussed. The rationale for selecting General Dynamics/Convair's Satellite Telecommunication Analysis and Modeling Program (STAMP) in modified form to aid in the system costing and sensitivity analysis work in the Program on…

  8. Computer Simulation as an Aid to Managers of Training.

    ERIC Educational Resources Information Center

    Wagner, Harold; Butler, Patrick J.

    Research investigated computer simulations of a hypothetical self-paced training program to determine the utility of this technique as a planning aid for Army training program managers. The General Purpose Simulation System (GPSS) was selected as the programing language and the study was divided into three stages. In Stage I, the daily number of…

  9. Toward Computer-Aided Affective Learning Systems: A Literature Review

    ERIC Educational Resources Information Center

    Moridis, C. N.; Economides, A. A.

    2008-01-01

    The aim of this survey is to provide an overview of the various components of "computer aided affective learning systems." The research is classified into 3 main scientific areas that are integral parts of the development of these kinds of systems. The three main scientific areas are: i) emotions and their connection to learning; ii) affect…

  10. eWorkbook: A Computer Aided Assessment System

    ERIC Educational Resources Information Center

    Costagliola, Gennaro; Ferrucci, Filomena; Fuccella, Vittorio; Oliveto, Rocco

    2007-01-01

    Computer aided assessment (CAA) tools are more and more widely adopted in academic environments mixed to other assessment means. In this article, we present a CAA Web application, named eWorkbook, which can be used for evaluating learner's knowledge by creating (the tutor) and taking (the learner) on-line tests based on multiple choice, multiple…

  11. Computer Aided Evaluation of Higher Education Tutors' Performance

    ERIC Educational Resources Information Center

    Xenos, Michalis; Papadopoulos, Thanos

    2007-01-01

    This article presents a method for computer-aided tutor evaluation: Bayesian Networks are used for organizing the collected data about tutors and for enabling accurate estimations and predictions about future tutor behavior. The model provides indications about each tutor's strengths and weaknesses, which enables the evaluator to exploit strengths…

  12. Does Computer-Aided Formative Assessment Improve Learning Outcomes?

    ERIC Educational Resources Information Center

    Hannah, John; James, Alex; Williams, Phillipa

    2014-01-01

    Two first-year engineering mathematics courses used computer-aided assessment (CAA) to provide students with opportunities for formative assessment via a series of weekly quizzes. Most students used the assessment until they achieved very high (>90%) quiz scores. Although there is a positive correlation between these quiz marks and the final…

  13. Evaluation and Assessment of a Biomechanics Computer-Aided Instruction.

    ERIC Educational Resources Information Center

    Washington, N.; Parnianpour, M.; Fraser, J. M.

    1999-01-01

    Describes the Biomechanics Tutorial, a computer-aided instructional tool that was developed at Ohio State University to expedite the transition from lecture to application for undergraduate students. Reports evaluation results that used statistical analyses and student questionnaires to show improved performance on posttests as well as positive…

  14. The Use of Computers to Aid Instruction in Beginning Chemistry

    ERIC Educational Resources Information Center

    Grandey, Robert C.

    1971-01-01

    Describes computer-aided lessons for determining chemical formulas from composition by weight, quantities from chemical equations, and balancing equations for oxidation-reduction reactions. Lessons were developed and used on the PLATO system at the University of Illinois. A brief analysis of student attitudes and of effectiveness of the programs…

  15. Computer-aided petrographic analysis of sandstones

    SciTech Connect

    Thayer, P.A.; Helmold, K.P.

    1987-05-01

    Thin-section point counting, mathematical and statistical analysis of petrographic-petrophysical data, report generation, and graphical presentation of results can be done efficiently by computer. Compositional and textural data are collected with a modified Schares point-counting system. The system uses an MS-DOS microcomputer programmed in BASIC to drive a motorized stage attached to a polarizing microscope. Numeric codes for up to 500 different categories of minerals, cements, pores, etc, are input using a separate keypad. Calculation and printing of constituent percentages, QFR, Folk name, and grain-size distribution are completed in seconds after data entry. Raw data files, compatible with software such as Lotus 1-2-3, SPSS, and SAS, are stored on floppy disk. Petrographic data files are transferred directly to a mainframe, merged with log and petrophysical data, analyzed statistically with SAS, and reports generated. SAS/GRAPH and TELL-A-GRAF routines linked with SAS generate a variety of cross plots, histograms, pie and bar charts, ternary diagrams, and vertical variation diagrams (e.g., depth vs. porosity, permeability, mean size, sorting, and percent grains-matrix-cement).

  16. Computer-Aided Designing and Manufacturing of Lingual Fixed Orthodontic Appliance Using 2D/3D Registration Software and Rapid Prototyping

    PubMed Central

    Kwon, Soon-Yong; Kim, Ki-Beom; Chung, Kyu-Rhim; Kim (Sunny), Seong-Hun

    2014-01-01

    The availability of 3D dental model scanning technology, combined with the ability to register CBCT data with digital models, has enabled the fabrication of orthognathic surgical CAD/CAM designed splints, customized brackets, and indirect bonding systems. In this study, custom lingual orthodontic appliances were virtually designed by merging 3D model images with lateral and posterior-anterior cephalograms. By exporting design information to 3D CAD software, we have produced a stereolithographic prototype and converted it into a cobalt-chrome alloy appliance as a way of combining traditional prosthetic investment and cast techniques. While the bonding procedure of the appliance could be reinforced, CAD technology simplified the fabrication process by eliminating the soldering phase. This report describes CAD/CAM fabrication of the complex anteroposterior lingual bonded retraction appliance for intrusive retraction of the maxillary anterior dentition. Furthermore, the CAD/CAM method eliminates the extra step of determining the lever arm on the lateral cephalograms and subsequent design modifications on the study model. PMID:24899895

  17. Computer-Aided Designing and Manufacturing of Lingual Fixed Orthodontic Appliance Using 2D/3D Registration Software and Rapid Prototyping.

    PubMed

    Kwon, Soon-Yong; Kim, Yong; Ahn, Hyo-Won; Kim, Ki-Beom; Chung, Kyu-Rhim; Kim Sunny, Seong-Hun

    2014-01-01

    The availability of 3D dental model scanning technology, combined with the ability to register CBCT data with digital models, has enabled the fabrication of orthognathic surgical CAD/CAM designed splints, customized brackets, and indirect bonding systems. In this study, custom lingual orthodontic appliances were virtually designed by merging 3D model images with lateral and posterior-anterior cephalograms. By exporting design information to 3D CAD software, we have produced a stereolithographic prototype and converted it into a cobalt-chrome alloy appliance as a way of combining traditional prosthetic investment and cast techniques. While the bonding procedure of the appliance could be reinforced, CAD technology simplified the fabrication process by eliminating the soldering phase. This report describes CAD/CAM fabrication of the complex anteroposterior lingual bonded retraction appliance for intrusive retraction of the maxillary anterior dentition. Furthermore, the CAD/CAM method eliminates the extra step of determining the lever arm on the lateral cephalograms and subsequent design modifications on the study model.

  18. Computer-aided determination of occlusal contact points for dental 3-D CAD.

    PubMed

    Maruyama, Tomoaki; Nakamura, Yasuo; Hayashi, Toyohiko; Kato, Kazumasa

    2006-05-01

    Present dental CAD systems enable us to design functional occlusal tooth surfaces which harmonize with the patient's stomatognathic function. In order to avoid occlusal interferences during tooth excursions, currently available systems usually use the patient's functional occlusal impressions for the design of occlusal contact points. Previous interfere-free design, however, has been done on a trial-and-error basis by using visual inspection. To improve this time-consuming procedure, this paper proposes a computer-aided system for assisting in the determination of the occlusal contact points by visualizing the appropriate regions of the opposing surface. The system can designate such regions from data of the opposing occlusal surfaces and their relative movements can be simulated by using a virtual articulator. Experiments for designing the crown of a lower first molar demonstrated that all contact points selected within the designated regions completely satisfied the required contact or separation during tooth excursions, confirming the effectiveness of our computer-aided procedure.

  19. PCACE- PERSONAL COMPUTER AIDED CABLING ENGINEERING

    NASA Technical Reports Server (NTRS)

    Billitti, J. W.

    1994-01-01

    A computerized interactive harness engineering program has been developed to provide an inexpensive, interactive system which is designed for learning and using an engineering approach to interconnection systems. PCACE is basically a database system that stores information as files of individual connectors and handles wiring information in circuit groups stored as records. This directly emulates the typical manual engineering methods of data handling, thus making the user interface to the program very natural. Data files can be created, viewed, manipulated, or printed in real time. The printed ouput is in a form ready for use by fabrication and engineering personnel. PCACE also contains a wide variety of error-checking routines including connector contact checks during hardcopy generation. The user may edit existing harness data files or create new files. In creating a new file, the user is given the opportunity to insert all the connector and harness boiler plate data which would be part of a normal connector wiring diagram. This data includes the following: 1) connector reference designator, 2) connector part number, 3) backshell part number, 4) cable reference designator, 5) cable part number, 6) drawing revision, 7) relevant notes, 8) standard wire gauge, and 9) maximum circuit count. Any item except the maximum circuit count may be left blank, and any item may be changed at a later time. Once a file is created and organized, the user is directed to the main menu and has access to the file boiler plate, the circuit wiring records, and the wiring records index list. The organization of a file is such that record zero contains the connector/cable boiler plate, and all other records contain circuit wiring data. Each wiring record will handle a circuit with as many as nine wires in the interface. The record stores the circuit name and wire count and the following data for each wire: 1) wire identifier, 2) contact, 3) splice, 4) wire gauge if different from standard

  20. Computer-Aided Engineering Of Cabling

    NASA Technical Reports Server (NTRS)

    Billitti, Joseph W.

    1989-01-01

    Program generates data sheets, drawings, and other information on electrical connections. DFACS program, centered around single data base, has built-in menus providing easy input of, and access to, data for all personnel involved in system, subsystem, and cabling. Enables parallel design of circuit-data sheets and drawings of harnesses. Also recombines raw information to generate automatically various project documents and drawings, including index of circuit-data sheets, list of electrical-interface circuits, lists of assemblies and equipment, cabling trees, and drawings of cabling electrical interfaces and harnesses. Purpose of program to provide engineering community with centralized data base for putting in, and gaining access to, functional definition of system as specified in terms of details of pin connections of end circuits of subsystems and instruments and data on harnessing. Primary objective to provide instantaneous single point of interchange of information, thus avoiding