Sample records for design code system

  1. Mean Line Pump Flow Model in Rocket Engine System Simulation

    NASA Technical Reports Server (NTRS)

    Veres, Joseph P.; Lavelle, Thomas M.

    2000-01-01

    A mean line pump flow modeling method has been developed to provide a fast capability for modeling turbopumps of rocket engines. Based on this method, a mean line pump flow code PUMPA has been written that can predict the performance of pumps at off-design operating conditions, given the loss of the diffusion system at the design point. The pump code can model axial flow inducers, mixed-flow and centrifugal pumps. The code can model multistage pumps in series. The code features rapid input setup and computer run time, and is an effective analysis and conceptual design tool. The map generation capability of the code provides the map information needed for interfacing with a rocket engine system modeling code. The off-design and multistage modeling capabilities of the code permit parametric design space exploration of candidate pump configurations and provide pump performance data for engine system evaluation. The PUMPA code has been integrated with the Numerical Propulsion System Simulation (NPSS) code and an expander rocket engine system has been simulated. The mean line pump flow code runs as an integral part of the NPSS rocket engine system simulation and provides key pump performance information directly to the system model at all operating conditions.

  2. System Design Description for the TMAD Code

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

    Finfrock, S.H.

    This document serves as the System Design Description (SDD) for the TMAD Code System, which includes the TMAD code and the LIBMAKR code. The SDD provides a detailed description of the theory behind the code, and the implementation of that theory. It is essential for anyone who is attempting to review or modify the code or who otherwise needs to understand the internal workings of the code. In addition, this document includes, in Appendix A, the System Requirements Specification for the TMAD System.

  3. Automated Concurrent Blackboard System Generation in C++

    NASA Technical Reports Server (NTRS)

    Kaplan, J. A.; McManus, J. W.; Bynum, W. L.

    1999-01-01

    In his 1992 Ph.D. thesis, "Design and Analysis Techniques for Concurrent Blackboard Systems", John McManus defined several performance metrics for concurrent blackboard systems and developed a suite of tools for creating and analyzing such systems. These tools allow a user to analyze a concurrent blackboard system design and predict the performance of the system before any code is written. The design can be modified until simulated performance is satisfactory. Then, the code generator can be invoked to generate automatically all of the code required for the concurrent blackboard system except for the code implementing the functionality of each knowledge source. We have completed the port of the source code generator and a simulator for a concurrent blackboard system. The source code generator generates the necessary C++ source code to implement the concurrent blackboard system using Parallel Virtual Machine (PVM) running on a heterogeneous network of UNIX(trademark) workstations. The concurrent blackboard simulator uses the blackboard specification file to predict the performance of the concurrent blackboard design. The only part of the source code for the concurrent blackboard system that the user must supply is the code implementing the functionality of the knowledge sources.

  4. System Design for FEC in Aeronautical Telemetry

    DTIC Science & Technology

    2012-03-12

    rate punctured convolutional codes for soft decision Viterbi...below follows that given in [8]. The final coding rate of exactly 2/3 is achieved by puncturing the rate -1/2 code as follows. We begin with the buffer c1...concatenated convolutional code (SCCC). The contributions of this paper are on the system-design level. One major contribution is to design a SCCC code

  5. Evaluation and implementation of QR Code Identity Tag system for Healthcare in Turkey.

    PubMed

    Uzun, Vassilya; Bilgin, Sami

    2016-01-01

    For this study, we designed a QR Code Identity Tag system to integrate into the Turkish healthcare system. This system provides QR code-based medical identification alerts and an in-hospital patient identification system. Every member of the medical system is assigned a unique QR Code Tag; to facilitate medical identification alerts, the QR Code Identity Tag can be worn as a bracelet or necklace or carried as an ID card. Patients must always possess the QR Code Identity bracelets within hospital grounds. These QR code bracelets link to the QR Code Identity website, where detailed information is stored; a smartphone or standalone QR code scanner can be used to scan the code. The design of this system allows authorized personnel (e.g., paramedics, firefighters, or police) to access more detailed patient information than the average smartphone user: emergency service professionals are authorized to access patient medical histories to improve the accuracy of medical treatment. In Istanbul, we tested the self-designed system with 174 participants. To analyze the QR Code Identity Tag system's usability, the participants completed the System Usability Scale questionnaire after using the system.

  6. Joint design of QC-LDPC codes for coded cooperation system with joint iterative decoding

    NASA Astrophysics Data System (ADS)

    Zhang, Shunwai; Yang, Fengfan; Tang, Lei; Ejaz, Saqib; Luo, Lin; Maharaj, B. T.

    2016-03-01

    In this paper, we investigate joint design of quasi-cyclic low-density-parity-check (QC-LDPC) codes for coded cooperation system with joint iterative decoding in the destination. First, QC-LDPC codes based on the base matrix and exponent matrix are introduced, and then we describe two types of girth-4 cycles in QC-LDPC codes employed by the source and relay. In the equivalent parity-check matrix corresponding to the jointly designed QC-LDPC codes employed by the source and relay, all girth-4 cycles including both type I and type II are cancelled. Theoretical analysis and numerical simulations show that the jointly designed QC-LDPC coded cooperation well combines cooperation gain and channel coding gain, and outperforms the coded non-cooperation under the same conditions. Furthermore, the bit error rate performance of the coded cooperation employing jointly designed QC-LDPC codes is better than those of random LDPC codes and separately designed QC-LDPC codes over AWGN channels.

  7. The design of wavefront coded imaging system

    NASA Astrophysics Data System (ADS)

    Lan, Shun; Cen, Zhaofeng; Li, Xiaotong

    2016-10-01

    Wavefront Coding is a new method to extend the depth of field, which combines optical design and signal processing together. By using optical design software ZEMAX ,we designed a practical wavefront coded imaging system based on a conventional Cooke triplet system .Unlike conventional optical system, the wavefront of this new system is modulated by a specially designed phase mask, which makes the point spread function (PSF)of optical system not sensitive to defocus. Therefore, a series of same blurred images obtained at the image plane. In addition, the optical transfer function (OTF) of the wavefront coded imaging system is independent of focus, which is nearly constant with misfocus and has no regions of zeros. All object information can be completely recovered through digital filtering at different defocus positions. The focus invariance of MTF is selected as merit function in this design. And the coefficients of phase mask are set as optimization goals. Compared to conventional optical system, wavefront coded imaging system obtains better quality images under different object distances. Some deficiencies appear in the restored images due to the influence of digital filtering algorithm, which are also analyzed in this paper. The depth of field of the designed wavefront coded imaging system is about 28 times larger than initial optical system, while keeping higher optical power and resolution at the image plane.

  8. W-026, Waste Receiving and Processing Facility data management system validation and verification report

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

    Palmer, M.E.

    1997-12-05

    This V and V Report includes analysis of two revisions of the DMS [data management system] System Requirements Specification (SRS) and the Preliminary System Design Document (PSDD); the source code for the DMS Communication Module (DMSCOM) messages; the source code for selected DMS Screens, and the code for the BWAS Simulator. BDM Federal analysts used a series of matrices to: compare the requirements in the System Requirements Specification (SRS) to the specifications found in the System Design Document (SDD), to ensure the design supports the business functions, compare the discreet parts of the SDD with each other, to ensure thatmore » the design is consistent and cohesive, compare the source code of the DMS Communication Module with the specifications, to ensure that the resultant messages will support the design, compare the source code of selected screens to the specifications to ensure that resultant system screens will support the design, compare the source code of the BWAS simulator with the requirements to interface with DMS messages and data transfers relating to the BWAS operations.« less

  9. Design of ACM system based on non-greedy punctured LDPC codes

    NASA Astrophysics Data System (ADS)

    Lu, Zijun; Jiang, Zihong; Zhou, Lin; He, Yucheng

    2017-08-01

    In this paper, an adaptive coded modulation (ACM) scheme based on rate-compatible LDPC (RC-LDPC) codes was designed. The RC-LDPC codes were constructed by a non-greedy puncturing method which showed good performance in high code rate region. Moreover, the incremental redundancy scheme of LDPC-based ACM system over AWGN channel was proposed. By this scheme, code rates vary from 2/3 to 5/6 and the complication of the ACM system is lowered. Simulations show that more and more obvious coding gain can be obtained by the proposed ACM system with higher throughput.

  10. Nuclear thermal propulsion engine system design analysis code development

    NASA Astrophysics Data System (ADS)

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

    1992-01-01

    A Nuclear Thermal Propulsion (NTP) Engine System Design Analyis Code has recently been developed to characterize key NTP engine system design features. Such a versatile, standalone NTP system performance and engine design code is required to support ongoing and future engine system and vehicle design efforts associated with proposed Space Exploration Initiative (SEI) missions of interest. Key areas of interest in the engine system modeling effort were the reactor, shielding, and inclusion of an engine multi-redundant propellant pump feed system design option. A solid-core nuclear thermal reactor and internal shielding code model was developed to estimate the reactor's thermal-hydraulic and physical parameters based on a prescribed thermal output which was integrated into a state-of-the-art engine system design model. The reactor code module has the capability to model graphite, composite, or carbide fuels. Key output from the model consists of reactor parameters such as thermal power, pressure drop, thermal profile, and heat generation in cooled structures (reflector, shield, and core supports), as well as the engine system parameters such as weight, dimensions, pressures, temperatures, mass flows, and performance. The model's overall analysis methodology and its key assumptions and capabilities are summarized in this paper.

  11. Channel coding in the space station data system network

    NASA Technical Reports Server (NTRS)

    Healy, T.

    1982-01-01

    A detailed discussion of the use of channel coding for error correction, privacy/secrecy, channel separation, and synchronization is presented. Channel coding, in one form or another, is an established and common element in data systems. No analysis and design of a major new system would fail to consider ways in which channel coding could make the system more effective. The presence of channel coding on TDRS, Shuttle, the Advanced Communication Technology Satellite Program system, the JSC-proposed Space Operations Center, and the proposed 30/20 GHz Satellite Communication System strongly support the requirement for the utilization of coding for the communications channel. The designers of the space station data system have to consider the use of channel coding.

  12. Incorporating Manual and Autonomous Code Generation

    NASA Technical Reports Server (NTRS)

    McComas, David

    1998-01-01

    Code can be generated manually or using code-generated software tools, but how do you interpret the two? This article looks at a design methodology that combines object-oriented design with autonomic code generation for attitude control flight software. Recent improvements in space flight computers are allowing software engineers to spend more time engineering the applications software. The application developed was the attitude control flight software for an astronomical satellite called the Microwave Anisotropy Probe (MAP). The MAP flight system is being designed, developed, and integrated at NASA's Goddard Space Flight Center. The MAP controls engineers are using Integrated Systems Inc.'s MATRIXx for their controls analysis. In addition to providing a graphical analysis for an environment, MATRIXx includes an autonomic code generation facility called AutoCode. This article examines the forces that shaped the final design and describes three highlights of the design process: (1) Defining the manual to autonomic code interface; (2) Applying object-oriented design to the manual flight code; (3) Implementing the object-oriented design in C.

  13. Rocketdyne/Westinghouse nuclear thermal rocket engine modeling

    NASA Technical Reports Server (NTRS)

    Glass, James F.

    1993-01-01

    The topics are presented in viewgraph form and include the following: systems approach needed for nuclear thermal rocket (NTR) design optimization; generic NTR engine power balance codes; rocketdyne nuclear thermal system code; software capabilities; steady state model; NTR engine optimizer code-logic; reactor power calculation logic; sample multi-component configuration; NTR design code output; generic NTR code at Rocketdyne; Rocketdyne NTR model; and nuclear thermal rocket modeling directions.

  14. Fixed-point Design of the Lattice-reduction-aided Iterative Detection and Decoding Receiver for Coded MIMO Systems

    DTIC Science & Technology

    2011-01-01

    reliability, e.g., Turbo Codes [2] and Low Density Parity Check ( LDPC ) codes [3]. The challenge to apply both MIMO and ECC into wireless systems is on...REPORT Fixed-point Design of theLattice-reduction-aided Iterative Detection andDecoding Receiver for Coded MIMO Systems 14. ABSTRACT 16. SECURITY...illustrates the performance of coded LR aided detectors. 1. REPORT DATE (DD-MM-YYYY) 4. TITLE AND SUBTITLE 13. SUPPLEMENTARY NOTES The views, opinions

  15. Centrifugal and Axial Pump Design and Off-Design Performance Prediction

    NASA Technical Reports Server (NTRS)

    Veres, Joseph P.

    1995-01-01

    A meanline pump-flow modeling method has been developed to provide a fast capability for modeling pumps of cryogenic rocket engines. Based on this method, a meanline pump-flow code PUMPA was written that can predict the performance of pumps at off-design operating conditions, given the loss of the diffusion system at the design point. The design-point rotor efficiency and slip factors are obtained from empirical correlations to rotor-specific speed and geometry. The pump code can model axial, inducer, mixed-flow, and centrifugal pumps and can model multistage pumps in series. The rapid input setup and computer run time for this meanline pump flow code make it an effective analysis and conceptual design tool. The map-generation capabilities of the code provide the information needed for interfacing with a rocket engine system modeling code. The off-design and multistage modeling capabilities of PUMPA permit the user to do parametric design space exploration of candidate pump configurations and to provide head-flow maps for engine system evaluation.

  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. National Underground Mines Inventory

    DTIC Science & Technology

    1983-10-01

    system is well designed to minimize water accumulation on the drift levels. In many areas, sufficient water has accumulated to make the use of boots a...four characters designate Field office. 17-18 State Code Pic 99 FIPS code for state in which minets located. 19-21 County Code Plc 999 FIPS code for... Designate a general product class based onSIC code. 28-29 Nine Type Plc 99 Natal/Nonmetal mine type code. Based on subunit operations code and canvass code

  18. High dynamic range coding imaging system

    NASA Astrophysics Data System (ADS)

    Wu, Renfan; Huang, Yifan; Hou, Guangqi

    2014-10-01

    We present a high dynamic range (HDR) imaging system design scheme based on coded aperture technique. This scheme can help us obtain HDR images which have extended depth of field. We adopt Sparse coding algorithm to design coded patterns. Then we utilize the sensor unit to acquire coded images under different exposure settings. With the guide of the multiple exposure parameters, a series of low dynamic range (LDR) coded images are reconstructed. We use some existing algorithms to fuse and display a HDR image by those LDR images. We build an optical simulation model and get some simulation images to verify the novel system.

  19. National Combustion Code: Parallel Performance

    NASA Technical Reports Server (NTRS)

    Babrauckas, Theresa

    2001-01-01

    This report discusses the National Combustion Code (NCC). The NCC is an integrated system of codes for the design and analysis of combustion systems. The advanced features of the NCC meet designers' requirements for model accuracy and turn-around time. The fundamental features at the inception of the NCC were parallel processing and unstructured mesh. The design and performance of the NCC are discussed.

  20. Performance enhancement of optical code-division multiple-access systems using transposed modified Walsh code

    NASA Astrophysics Data System (ADS)

    Sikder, Somali; Ghosh, Shila

    2018-02-01

    This paper presents the construction of unipolar transposed modified Walsh code (TMWC) and analysis of its performance in optical code-division multiple-access (OCDMA) systems. Specifically, the signal-to-noise ratio, bit error rate (BER), cardinality, and spectral efficiency were investigated. The theoretical analysis demonstrated that the wavelength-hopping time-spreading system using TMWC was robust against multiple-access interference and more spectrally efficient than systems using other existing OCDMA codes. In particular, the spectral efficiency was calculated to be 1.0370 when TMWC of weight 3 was employed. The BER and eye pattern for the designed TMWC were also successfully obtained using OptiSystem simulation software. The results indicate that the proposed code design is promising for enhancing network capacity.

  1. HERCULES: A Pattern Driven Code Transformation System

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

    Kartsaklis, Christos; Hernandez, Oscar R; Hsu, Chung-Hsing

    2012-01-01

    New parallel computers are emerging, but developing efficient scientific code for them remains difficult. A scientist must manage not only the science-domain complexity but also the performance-optimization complexity. HERCULES is a code transformation system designed to help the scientist to separate the two concerns, which improves code maintenance, and facilitates performance optimization. The system combines three technologies, code patterns, transformation scripts and compiler plugins, to provide the scientist with an environment to quickly implement code transformations that suit his needs. Unlike existing code optimization tools, HERCULES is unique in its focus on user-level accessibility. In this paper we discuss themore » design, implementation and an initial evaluation of HERCULES.« less

  2. 42 CFR 405.512 - Carriers' procedural terminology and coding systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 2 2013-10-01 2013-10-01 false Carriers' procedural terminology and coding systems... Determining Reasonable Charges § 405.512 Carriers' procedural terminology and coding systems. (a) General. Procedural terminology and coding systems are designed to provide physicians and third party payers with a...

  3. 42 CFR 405.512 - Carriers' procedural terminology and coding systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 2 2011-10-01 2011-10-01 false Carriers' procedural terminology and coding systems... Determining Reasonable Charges § 405.512 Carriers' procedural terminology and coding systems. (a) General. Procedural terminology and coding systems are designed to provide physicians and third party payers with a...

  4. 42 CFR 405.512 - Carriers' procedural terminology and coding systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 2 2014-10-01 2014-10-01 false Carriers' procedural terminology and coding systems... Determining Reasonable Charges § 405.512 Carriers' procedural terminology and coding systems. (a) General. Procedural terminology and coding systems are designed to provide physicians and third party payers with a...

  5. 42 CFR 405.512 - Carriers' procedural terminology and coding systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 2 2012-10-01 2012-10-01 false Carriers' procedural terminology and coding systems... Determining Reasonable Charges § 405.512 Carriers' procedural terminology and coding systems. (a) General. Procedural terminology and coding systems are designed to provide physicians and third party payers with a...

  6. 42 CFR 405.512 - Carriers' procedural terminology and coding systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Carriers' procedural terminology and coding systems... Determining Reasonable Charges § 405.512 Carriers' procedural terminology and coding systems. (a) General. Procedural terminology and coding systems are designed to provide physicians and third party payers with a...

  7. A Review on Spectral Amplitude Coding Optical Code Division Multiple Access

    NASA Astrophysics Data System (ADS)

    Kaur, Navpreet; Goyal, Rakesh; Rani, Monika

    2017-06-01

    This manuscript deals with analysis of Spectral Amplitude Coding Optical Code Division Multiple Access (SACOCDMA) system. The major noise source in optical CDMA is co-channel interference from other users known as multiple access interference (MAI). The system performance in terms of bit error rate (BER) degrades as a result of increased MAI. It is perceived that number of users and type of codes used for optical system directly decide the performance of system. MAI can be restricted by efficient designing of optical codes and implementing them with unique architecture to accommodate more number of users. Hence, it is a necessity to design a technique like spectral direct detection (SDD) technique with modified double weight code, which can provide better cardinality and good correlation property.

  8. Coordinated design of coding and modulation systems

    NASA Technical Reports Server (NTRS)

    Massey, J. L.; Ancheta, T.; Johannesson, R.; Lauer, G.; Lee, L.

    1976-01-01

    The joint optimization of the coding and modulation systems employed in telemetry systems was investigated. Emphasis was placed on formulating inner and outer coding standards used by the Goddard Spaceflight Center. Convolutional codes were found that are nearly optimum for use with Viterbi decoding in the inner coding of concatenated coding systems. A convolutional code, the unit-memory code, was discovered and is ideal for inner system usage because of its byte-oriented structure. Simulations of sequential decoding on the deep-space channel were carried out to compare directly various convolutional codes that are proposed for use in deep-space systems.

  9. 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.

  10. Low-density parity-check codes for volume holographic memory systems.

    PubMed

    Pishro-Nik, Hossein; Rahnavard, Nazanin; Ha, Jeongseok; Fekri, Faramarz; Adibi, Ali

    2003-02-10

    We investigate the application of low-density parity-check (LDPC) codes in volume holographic memory (VHM) systems. We show that a carefully designed irregular LDPC code has a very good performance in VHM systems. We optimize high-rate LDPC codes for the nonuniform error pattern in holographic memories to reduce the bit error rate extensively. The prior knowledge of noise distribution is used for designing as well as decoding the LDPC codes. We show that these codes have a superior performance to that of Reed-Solomon (RS) codes and regular LDPC counterparts. Our simulation shows that we can increase the maximum storage capacity of holographic memories by more than 50 percent if we use irregular LDPC codes with soft-decision decoding instead of conventionally employed RS codes with hard-decision decoding. The performance of these LDPC codes is close to the information theoretic capacity.

  11. Design of Optical Systems with Extended Depth of Field: An Educational Approach to Wavefront Coding Techniques

    ERIC Educational Resources Information Center

    Ferran, C.; Bosch, S.; Carnicer, A.

    2012-01-01

    A practical activity designed to introduce wavefront coding techniques as a method to extend the depth of field in optical systems is presented. The activity is suitable for advanced undergraduate students since it combines different topics in optical engineering such as optical system design, aberration theory, Fourier optics, and digital image…

  12. Use of Generalized Fluid System Simulation Program (GFSSP) for Teaching and Performing Senior Design Projects at the Educational Institutions

    NASA Technical Reports Server (NTRS)

    Majumdar, A. K.; Hedayat, A.

    2015-01-01

    This paper describes the experience of the authors in using the Generalized Fluid System Simulation Program (GFSSP) in teaching Design of Thermal Systems class at University of Alabama in Huntsville. GFSSP is a finite volume based thermo-fluid system network analysis code, developed at NASA/Marshall Space Flight Center, and is extensively used in NASA, Department of Defense, and aerospace industries for propulsion system design, analysis, and performance evaluation. The educational version of GFSSP is freely available to all US higher education institutions. The main purpose of the paper is to illustrate the utilization of this user-friendly code for the thermal systems design and fluid engineering courses and to encourage the instructors to utilize the code for the class assignments as well as senior design projects.

  13. Final Report Advanced Quasioptical Launcher System

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

    Jeffrey Neilson

    2010-04-30

    This program developed an analytical design tool for designing antenna and mirror systems to convert whispering gallery RF modes to Gaussian or HE11 modes. Whispering gallery modes are generated by gyrotrons used for electron cyclotron heating of fusion plasmas in tokamaks. These modes cannot be easily transmitted and must be converted to free space or waveguide modes compatible with transmission line systems.This program improved the capability of SURF3D/LOT, which was initially developed in a previous SBIR program. This suite of codes revolutionized quasi-optical launcher design, and this code, or equivalent codes, are now used worldwide. This program added functionality tomore » SURF3D/LOT to allow creating of more compact launcher and mirror systems and provide direct coupling to corrugated waveguide within the vacuum envelope of the gyrotron. Analysis was also extended to include full-wave analysis of mirror transmission line systems. The code includes a graphical user interface and is available for advanced design of launcher systems.« less

  14. 76 FR 11432 - Coding of Design Marks in Registrations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-02

    ... on the old paper search designations. The USPTO will continue to code all pending applications that... system, the Trademark Search Facility Classification Code Index (``TC Index''), stems from its... infrequent use of the TC Index codes in searches by the public; and its costliness to maintain, especially in...

  15. The design of the CMOS wireless bar code scanner applying optical system based on ZigBee

    NASA Astrophysics Data System (ADS)

    Chen, Yuelin; Peng, Jian

    2008-03-01

    The traditional bar code scanner is influenced by the length of data line, but the farthest distance of the wireless bar code scanner of wireless communication is generally between 30m and 100m on the market. By rebuilding the traditional CCD optical bar code scanner, a CMOS code scanner is designed based on the ZigBee to meet the demands of market. The scan system consists of the CMOS image sensor and embedded chip S3C2401X, when the two dimensional bar code is read, the results show the inaccurate and wrong code bar, resulted from image defile, disturber, reads image condition badness, signal interference, unstable system voltage. So we put forward the method which uses the matrix evaluation and Read-Solomon arithmetic to solve them. In order to construct the whole wireless optics of bar code system and to ensure its ability of transmitting bar code image signals digitally with long distances, ZigBee is used to transmit data to the base station, and this module is designed based on image acquisition system, and at last the wireless transmitting/receiving CC2430 module circuit linking chart is established. And by transplanting the embedded RTOS system LINUX to the MCU, an applying wireless CMOS optics bar code scanner and multi-task system is constructed. Finally, performance of communication is tested by evaluation software Smart RF. In broad space, every ZIGBEE node can realize 50m transmission with high reliability. When adding more ZigBee nodes, the transmission distance can be several thousands of meters long.

  16. Design of wavefront coding optical system with annular aperture

    NASA Astrophysics Data System (ADS)

    Chen, Xinhua; Zhou, Jiankang; Shen, Weimin

    2016-10-01

    Wavefront coding can extend the depth of field of traditional optical system by inserting a phase mask into the pupil plane. In this paper, the point spread function (PSF) of wavefront coding system with annular aperture are analyzed. Stationary phase method and fast Fourier transform (FFT) method are used to compute the diffraction integral respectively. The OTF invariance is analyzed for the annular aperture with cubic phase mask under different obscuration ratio. With these analysis results, a wavefront coding system using Maksutov-Cassegrain configuration is designed finally. It is an F/8.21 catadioptric system with annular aperture, and its focal length is 821mm. The strength of the cubic phase mask is optimized with user-defined operand in Zemax. The Wiener filtering algorithm is used to restore the images and the numerical simulation proves the validity of the design.

  17. Design study of a HEAO-C spread spectrum transponder telemetry system for use with the TDRSS subnet

    NASA Technical Reports Server (NTRS)

    Weathers, G.

    1975-01-01

    The results of a design study of a spread spectrum transponder for use on the HEAO-C satellite were given. The transponder performs the functions of code turn-around for ground range and range-rate determination, ground command receiver, and telemetry data transmitter. The spacecraft transponder and associated communication system components will allow the HEAO-C satellite to utilize the Tracking and Data Relay Satellite System (TDRSS) subnet of the post 1978 STDN. The following areas were discussed in the report: TDRSS Subnet Description, TDRSS-HEAO-C System Configuration, Gold Code Generator, Convolutional Encoder Design and Decoder Algorithm, High Speed Sequence Generators, Statistical Evaluation of Candidate Code Sequences using Amplitude and Phase Moments, Code and Carrier Phase Lock Loops, Total Spread Spectrum Transponder System, and Reference Literature Search.

  18. Numerical predictions of EML (electromagnetic launcher) system performance

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

    Schnurr, N.M.; Kerrisk, J.F.; Davidson, R.F.

    1987-01-01

    The performance of an electromagnetic launcher (EML) depends on a large number of parameters, including the characteristics of the power supply, rail geometry, rail and insulator material properties, injection velocity, and projectile mass. EML system performance is frequently limited by structural or thermal effects in the launcher (railgun). A series of computer codes has been developed at the Los Alamos National Laboratory to predict EML system performance and to determine the structural and thermal constraints on barrel design. These codes include FLD, a two-dimensional electrostatic code used to calculate the high-frequency inductance gradient and surface current density distribution for themore » rails; TOPAZRG, a two-dimensional finite-element code that simultaneously analyzes thermal and electromagnetic diffusion in the rails; and LARGE, a code that predicts the performance of the entire EML system. Trhe NIKE2D code, developed at the Lawrence Livermore National Laboratory, is used to perform structural analyses of the rails. These codes have been instrumental in the design of the Lethality Test System (LTS) at Los Alamos, which has an ultimate goal of accelerating a 30-g projectile to a velocity of 15 km/s. The capabilities of the individual codes and the coupling of these codes to perform a comprehensive analysis is discussed in relation to the LTS design. Numerical predictions are compared with experimental data and presented for the LTS prototype tests.« less

  19. Industrial Code Development

    NASA Technical Reports Server (NTRS)

    Shapiro, Wilbur

    1991-01-01

    The industrial codes will consist of modules of 2-D and simplified 2-D or 1-D codes, intended for expeditious parametric studies, analysis, and design of a wide variety of seals. Integration into a unified system is accomplished by the industrial Knowledge Based System (KBS), which will also provide user friendly interaction, contact sensitive and hypertext help, design guidance, and an expandable database. The types of analysis to be included with the industrial codes are interfacial performance (leakage, load, stiffness, friction losses, etc.), thermoelastic distortions, and dynamic response to rotor excursions. The first three codes to be completed and which are presently being incorporated into the KBS are the incompressible cylindrical code, ICYL, and the compressible cylindrical code, GCYL.

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

    NASA Astrophysics Data System (ADS)

    Hellekson, Ron; Campbell, Scott

    1988-06-01

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

  1. Shaping electromagnetic waves using software-automatically-designed metasurfaces.

    PubMed

    Zhang, Qian; Wan, Xiang; Liu, Shuo; Yuan Yin, Jia; Zhang, Lei; Jun Cui, Tie

    2017-06-15

    We present a fully digital procedure of designing reflective coding metasurfaces to shape reflected electromagnetic waves. The design procedure is completely automatic, controlled by a personal computer. In details, the macro coding units of metasurface are automatically divided into several types (e.g. two types for 1-bit coding, four types for 2-bit coding, etc.), and each type of the macro coding units is formed by discretely random arrangement of micro coding units. By combining an optimization algorithm and commercial electromagnetic software, the digital patterns of the macro coding units are optimized to possess constant phase difference for the reflected waves. The apertures of the designed reflective metasurfaces are formed by arranging the macro coding units with certain coding sequence. To experimentally verify the performance, a coding metasurface is fabricated by automatically designing two digital 1-bit unit cells, which are arranged in array to constitute a periodic coding metasurface to generate the required four-beam radiations with specific directions. Two complicated functional metasurfaces with circularly- and elliptically-shaped radiation beams are realized by automatically designing 4-bit macro coding units, showing excellent performance of the automatic designs by software. The proposed method provides a smart tool to realize various functional devices and systems automatically.

  2. National Combustion Code, a Multidisciplinary Combustor Design System, Will Be Transferred to the Commercial Sector

    NASA Technical Reports Server (NTRS)

    Steele, Gynelle C.

    1999-01-01

    The NASA Lewis Research Center and Flow Parametrics will enter into an agreement to commercialize the National Combustion Code (NCC). This multidisciplinary combustor design system utilizes computer-aided design (CAD) tools for geometry creation, advanced mesh generators for creating solid model representations, a common framework for fluid flow and structural analyses, modern postprocessing tools, and parallel processing. This integrated system can facilitate and enhance various phases of the design and analysis process.

  3. Bar-Code System for a Microbiological Laboratory

    NASA Technical Reports Server (NTRS)

    Law, Jennifer; Kirschner, Larry

    2007-01-01

    A bar-code system has been assembled for a microbiological laboratory that must examine a large number of samples. The system includes a commercial bar-code reader, computer hardware and software components, plus custom-designed database software. The software generates a user-friendly, menu-driven interface.

  4. Ultra Safe And Secure Blasting System

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

    Hart, M M

    2009-07-27

    The Ultra is a blasting system that is designed for special applications where the risk and consequences of unauthorized demolition or blasting are so great that the use of an extraordinarily safe and secure blasting system is justified. Such a blasting system would be connected and logically welded together through digital code-linking as part of the blasting system set-up and initialization process. The Ultra's security is so robust that it will defeat the people who designed and built the components in any attempt at unauthorized detonation. Anyone attempting to gain unauthorized control of the system by substituting components or tappingmore » into communications lines will be thwarted in their inability to provide encrypted authentication. Authentication occurs through the use of codes that are generated by the system during initialization code-linking and the codes remain unknown to anyone, including the authorized operator. Once code-linked, a closed system has been created. The system requires all components connected as they were during initialization as well as a unique code entered by the operator for function and blasting.« less

  5. 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.

  6. Recent improvements of reactor physics codes in MHI

    NASA Astrophysics Data System (ADS)

    Kosaka, Shinya; Yamaji, Kazuya; Kirimura, Kazuki; Kamiyama, Yohei; Matsumoto, Hideki

    2015-12-01

    This paper introduces recent improvements for reactor physics codes in Mitsubishi Heavy Industries, Ltd(MHI). MHI has developed a new neutronics design code system Galaxy/Cosmo-S(GCS) for PWR core analysis. After TEPCO's Fukushima Daiichi accident, it is required to consider design extended condition which has not been covered explicitly by the former safety licensing analyses. Under these circumstances, MHI made some improvements for GCS code system. A new resonance calculation model of lattice physics code and homogeneous cross section representative model for core simulator have been developed to apply more wide range core conditions corresponding to severe accident status such like anticipated transient without scram (ATWS) analysis and criticality evaluation of dried-up spent fuel pit. As a result of these improvements, GCS code system has very wide calculation applicability with good accuracy for any core conditions as far as fuel is not damaged. In this paper, the outline of GCS code system is described briefly and recent relevant development activities are presented.

  7. Recent improvements of reactor physics codes in MHI

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

    Kosaka, Shinya, E-mail: shinya-kosaka@mhi.co.jp; Yamaji, Kazuya; Kirimura, Kazuki

    2015-12-31

    This paper introduces recent improvements for reactor physics codes in Mitsubishi Heavy Industries, Ltd(MHI). MHI has developed a new neutronics design code system Galaxy/Cosmo-S(GCS) for PWR core analysis. After TEPCO’s Fukushima Daiichi accident, it is required to consider design extended condition which has not been covered explicitly by the former safety licensing analyses. Under these circumstances, MHI made some improvements for GCS code system. A new resonance calculation model of lattice physics code and homogeneous cross section representative model for core simulator have been developed to apply more wide range core conditions corresponding to severe accident status such like anticipatedmore » transient without scram (ATWS) analysis and criticality evaluation of dried-up spent fuel pit. As a result of these improvements, GCS code system has very wide calculation applicability with good accuracy for any core conditions as far as fuel is not damaged. In this paper, the outline of GCS code system is described briefly and recent relevant development activities are presented.« less

  8. Design geometry and design/off-design performance computer codes for compressors and turbines

    NASA Technical Reports Server (NTRS)

    Glassman, Arthur J.

    1995-01-01

    This report summarizes some NASA Lewis (i.e., government owned) computer codes capable of being used for airbreathing propulsion system studies to determine the design geometry and to predict the design/off-design performance of compressors and turbines. These are not CFD codes; velocity-diagram energy and continuity computations are performed fore and aft of the blade rows using meanline, spanline, or streamline analyses. Losses are provided by empirical methods. Both axial-flow and radial-flow configurations are included.

  9. Study on the properties of infrared wavefront coding athermal system under several typical temperature gradient distributions

    NASA Astrophysics Data System (ADS)

    Cai, Huai-yu; Dong, Xiao-tong; Zhu, Meng; Huang, Zhan-hua

    2018-01-01

    Wavefront coding for athermal technique can effectively ensure the stability of the optical system imaging in large temperature range, as well as the advantages of compact structure and low cost. Using simulation method to analyze the properties such as PSF and MTF of wavefront coding athermal system under several typical temperature gradient distributions has directive function to characterize the working state of non-ideal temperature environment, and can effectively realize the system design indicators as well. In this paper, we utilize the interoperability of data between Solidworks and ZEMAX to simplify the traditional process of structure/thermal/optical integrated analysis. Besides, we design and build the optical model and corresponding mechanical model of the infrared imaging wavefront coding athermal system. The axial and radial temperature gradients of different degrees are applied to the whole system by using SolidWorks software, thus the changes of curvature, refractive index and the distance between the lenses are obtained. Then, we import the deformation model to ZEMAX for ray tracing, and obtain the changes of PSF and MTF in optical system. Finally, we discuss and evaluate the consistency of the PSF (MTF) of the wavefront coding athermal system and the image restorability, which provides the basis and reference for the optimal design of the wavefront coding athermal system. The results show that the adaptability of single material infrared wavefront coding athermal system to axial temperature gradient can reach the upper limit of temperature fluctuation of 60°C, which is much higher than that of radial temperature gradient.

  10. 10 CFR 50.55a - Codes and standards.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., standard design approval, and standard design certification application under part 52 of this chapter is... section. (a)(1) Structures, systems, and components must be designed, fabricated, erected, constructed... Guide 1.84, Revision 34, “Design, Fabrication, and Materials Code Case Acceptability, ASME Section III...

  11. 7 CFR 1724.50 - Compliance with National Electrical Safety Code (NESC).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 11 2013-01-01 2013-01-01 false Compliance with National Electrical Safety Code (NESC... UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE ELECTRIC ENGINEERING, ARCHITECTURAL SERVICES AND DESIGN POLICIES AND PROCEDURES Electric System Design § 1724.50 Compliance with National Electrical Safety Code...

  12. 7 CFR 1724.50 - Compliance with National Electrical Safety Code (NESC).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false Compliance with National Electrical Safety Code (NESC... UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE ELECTRIC ENGINEERING, ARCHITECTURAL SERVICES AND DESIGN POLICIES AND PROCEDURES Electric System Design § 1724.50 Compliance with National Electrical Safety Code...

  13. 7 CFR 1724.50 - Compliance with National Electrical Safety Code (NESC).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 11 2011-01-01 2011-01-01 false Compliance with National Electrical Safety Code (NESC... UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE ELECTRIC ENGINEERING, ARCHITECTURAL SERVICES AND DESIGN POLICIES AND PROCEDURES Electric System Design § 1724.50 Compliance with National Electrical Safety Code...

  14. 7 CFR 1724.50 - Compliance with National Electrical Safety Code (NESC).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 11 2012-01-01 2012-01-01 false Compliance with National Electrical Safety Code (NESC... UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE ELECTRIC ENGINEERING, ARCHITECTURAL SERVICES AND DESIGN POLICIES AND PROCEDURES Electric System Design § 1724.50 Compliance with National Electrical Safety Code...

  15. 7 CFR 1724.50 - Compliance with National Electrical Safety Code (NESC).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 11 2014-01-01 2014-01-01 false Compliance with National Electrical Safety Code (NESC... UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE ELECTRIC ENGINEERING, ARCHITECTURAL SERVICES AND DESIGN POLICIES AND PROCEDURES Electric System Design § 1724.50 Compliance with National Electrical Safety Code...

  16. ETF system code: composition and applications

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

    Reid, R.L.; Wu, K.F.

    1980-01-01

    A computer code has been developed for application to ETF tokamak system and conceptual design studies. The code determines cost, performance, configuration, and technology requirements as a function of tokamak parameters. The ETF code is structured in a modular fashion in order to allow independent modeling of each major tokamak component. The primary benefit of modularization is that it allows updating of a component module, such as the TF coil module, without disturbing the remainder of the system code as long as the input/output to the modules remains unchanged. The modules may be run independently to perform specific design studies,more » such as determining the effect of allowable strain on TF coil structural requirements, or the modules may be executed together as a system to determine global effects, such as defining the impact of aspect ratio on the entire tokamak system.« less

  17. Computer code for analyzing the performance of aquifer thermal energy storage systems

    NASA Astrophysics Data System (ADS)

    Vail, L. W.; Kincaid, C. T.; Kannberg, L. D.

    1985-05-01

    A code called Aquifer Thermal Energy Storage System Simulator (ATESSS) has been developed to analyze the operational performance of ATES systems. The ATESSS code provides an ability to examine the interrelationships among design specifications, general operational strategies, and unpredictable variations in the demand for energy. The uses of the code can vary the well field layout, heat exchanger size, and pumping/injection schedule. Unpredictable aspects of supply and demand may also be examined through the use of a stochastic model of selected system parameters. While employing a relatively simple model of the aquifer, the ATESSS code plays an important role in the design and operation of ATES facilities by augmenting experience provided by the relatively few field experiments and demonstration projects. ATESSS has been used to characterize the effect of different pumping/injection schedules on a hypothetical ATES system and to estimate the recovery at the St. Paul, Minnesota, field experiment.

  18. The use of interleaving for reducing radio loss in convolutionally coded systems

    NASA Technical Reports Server (NTRS)

    Divsalar, D.; Simon, M. K.; Yuen, J. H.

    1989-01-01

    The use of interleaving after convolutional coding and deinterleaving before Viterbi decoding is proposed. This effectively reduces radio loss at low-loop Signal to Noise Ratios (SNRs) by several decibels and at high-loop SNRs by a few tenths of a decibel. Performance of the coded system can further be enhanced if the modulation index is optimized for this system. This will correspond to a reduction of bit SNR at a certain bit error rate for the overall system. The introduction of interleaving/deinterleaving into communication systems designed for future deep space missions does not substantially complicate their hardware design or increase their system cost.

  19. Application of advanced computational codes in the design of an experiment for a supersonic throughflow fan rotor

    NASA Technical Reports Server (NTRS)

    Wood, Jerry R.; Schmidt, James F.; Steinke, Ronald J.; Chima, Rodrick V.; Kunik, William G.

    1987-01-01

    Increased emphasis on sustained supersonic or hypersonic cruise has revived interest in the supersonic throughflow fan as a possible component in advanced propulsion systems. Use of a fan that can operate with a supersonic inlet axial Mach number is attractive from the standpoint of reducing the inlet losses incurred in diffusing the flow from a supersonic flight Mach number to a subsonic one at the fan face. The design of the experiment using advanced computational codes to calculate the components required is described. The rotor was designed using existing turbomachinery design and analysis codes modified to handle fully supersonic axial flow through the rotor. A two-dimensional axisymmetric throughflow design code plus a blade element code were used to generate fan rotor velocity diagrams and blade shapes. A quasi-three-dimensional, thin shear layer Navier-Stokes code was used to assess the performance of the fan rotor blade shapes. The final design was stacked and checked for three-dimensional effects using a three-dimensional Euler code interactively coupled with a two-dimensional boundary layer code. The nozzle design in the expansion region was analyzed with a three-dimensional parabolized viscous code which corroborated the results from the Euler code. A translating supersonic diffuser was designed using these same codes.

  20. The Use of a Code-generating System for the Derivation of the Equations for Wind Turbine Dynamics

    NASA Astrophysics Data System (ADS)

    Ganander, Hans

    2003-10-01

    For many reasons the size of wind turbines on the rapidly growing wind energy market is increasing. Relations between aeroelastic properties of these new large turbines change. Modifications of turbine designs and control concepts are also influenced by growing size. All these trends require development of computer codes for design and certification. Moreover, there is a strong desire for design optimization procedures, which require fast codes. General codes, e.g. finite element codes, normally allow such modifications and improvements of existing wind turbine models. This is done relatively easy. However, the calculation times of such codes are unfavourably long, certainly for optimization use. The use of an automatic code generating system is an alternative for relevance of the two key issues, the code and the design optimization. This technique can be used for rapid generation of codes of particular wind turbine simulation models. These ideas have been followed in the development of new versions of the wind turbine simulation code VIDYN. The equations of the simulation model were derived according to the Lagrange equation and using Mathematica®, which was directed to output the results in Fortran code format. In this way the simulation code is automatically adapted to an actual turbine model, in terms of subroutines containing the equations of motion, definitions of parameters and degrees of freedom. Since the start in 1997, these methods, constituting a systematic way of working, have been used to develop specific efficient calculation codes. The experience with this technique has been very encouraging, inspiring the continued development of new versions of the simulation code as the need has arisen, and the interest for design optimization is growing.

  1. Error-correction coding for digital communications

    NASA Astrophysics Data System (ADS)

    Clark, G. C., Jr.; Cain, J. B.

    This book is written for the design engineer who must build the coding and decoding equipment and for the communication system engineer who must incorporate this equipment into a system. It is also suitable as a senior-level or first-year graduate text for an introductory one-semester course in coding theory. Fundamental concepts of coding are discussed along with group codes, taking into account basic principles, practical constraints, performance computations, coding bounds, generalized parity check codes, polynomial codes, and important classes of group codes. Other topics explored are related to simple nonalgebraic decoding techniques for group codes, soft decision decoding of block codes, algebraic techniques for multiple error correction, the convolutional code structure and Viterbi decoding, syndrome decoding techniques, and sequential decoding techniques. System applications are also considered, giving attention to concatenated codes, coding for the white Gaussian noise channel, interleaver structures for coded systems, and coding for burst noise channels.

  2. The Therapeutic Collaboration in Life Design Counselling: The Case of Ryan

    ERIC Educational Resources Information Center

    do Céu Taveira, Maria; Ribeiro, Eugénia; Cardoso, Paulo; Silva, Filipa

    2017-01-01

    This study examined the therapeutic collaboration in a case of Life Design Counseling (LDC) with narrative change and positive career outcomes. The therapeutic collaboration-change model and correspondent coding system were used to intensively study the helping relationship throughout three sessions of LDC. The collaboration coding system enables…

  3. Integrating automated structured analysis and design with Ada programming support environments

    NASA Technical Reports Server (NTRS)

    Hecht, Alan; Simmons, Andy

    1986-01-01

    Ada Programming Support Environments (APSE) include many powerful tools that address the implementation of Ada code. These tools do not address the entire software development process. Structured analysis is a methodology that addresses the creation of complete and accurate system specifications. Structured design takes a specification and derives a plan to decompose the system subcomponents, and provides heuristics to optimize the software design to minimize errors and maintenance. It can also produce the creation of useable modules. Studies have shown that most software errors result from poor system specifications, and that these errors also become more expensive to fix as the development process continues. Structured analysis and design help to uncover error in the early stages of development. The APSE tools help to insure that the code produced is correct, and aid in finding obscure coding errors. However, they do not have the capability to detect errors in specifications or to detect poor designs. An automated system for structured analysis and design TEAMWORK, which can be integrated with an APSE to support software systems development from specification through implementation is described. These tools completement each other to help developers improve quality and productivity, as well as to reduce development and maintenance costs. Complete system documentation and reusable code also resultss from the use of these tools. Integrating an APSE with automated tools for structured analysis and design provide capabilities and advantages beyond those realized with any of these systems used by themselves.

  4. The Integration of COTS/GOTS within NASA's HST Command and Control System

    NASA Technical Reports Server (NTRS)

    Pfarr, Thomas; Reis, James E.; Obenschain, Arthur F. (Technical Monitor)

    2001-01-01

    NASA's mission critical Hubble Space Telescope (HST) command and control system has been re-engineered with COTS/GOTS and minimal custom code. This paper focuses on the design of this new HST Control Center System (CCS) and the lessons learned throughout its development. CCS currently utilizes 31 COTS/GOTS products with an additional 12 million lines of custom glueware code; the new CCS exceeds the capabilities of the original system while significantly reducing the lines of custom code by more than 50%. The lifecycle of COTS/GOTS products will be examined including the pack-age selection process, evaluation process, and integration process. The advantages, disadvantages, issues, concerns, and lessons teamed for integrating COTS/GOTS into the NASA's mission critical HST CCS will be examined in detail. Command and control systems designed with traditional custom code development efforts will be compared with command and control systems designed with new development techniques relying heavily on COTS/COTS integration. This paper will reveal the many hidden costs of COTS/GOTS solutions when compared to traditional custom code development efforts; this paper will show the high cost of COTS/GOTS solutions including training expenses, consulting fees, and long-term maintenance expenses.

  5. Parallel Grand Canonical Monte Carlo (ParaGrandMC) Simulation Code

    NASA Technical Reports Server (NTRS)

    Yamakov, Vesselin I.

    2016-01-01

    This report provides an overview of the Parallel Grand Canonical Monte Carlo (ParaGrandMC) simulation code. This is a highly scalable parallel FORTRAN code for simulating the thermodynamic evolution of metal alloy systems at the atomic level, and predicting the thermodynamic state, phase diagram, chemical composition and mechanical properties. The code is designed to simulate multi-component alloy systems, predict solid-state phase transformations such as austenite-martensite transformations, precipitate formation, recrystallization, capillary effects at interfaces, surface absorption, etc., which can aid the design of novel metallic alloys. While the software is mainly tailored for modeling metal alloys, it can also be used for other types of solid-state systems, and to some degree for liquid or gaseous systems, including multiphase systems forming solid-liquid-gas interfaces.

  6. An ultrasound transient elastography system with coded excitation.

    PubMed

    Diao, Xianfen; Zhu, Jing; He, Xiaonian; Chen, Xin; Zhang, Xinyu; Chen, Siping; Liu, Weixiang

    2017-06-28

    Ultrasound transient elastography technology has found its place in elastography because it is safe and easy to operate. However, it's application in deep tissue is limited. The aim of this study is to design an ultrasound transient elastography system with coded excitation to obtain greater detection depth. The ultrasound transient elastography system requires tissue vibration to be strictly synchronous with ultrasound detection. Therefore, an ultrasound transient elastography system with coded excitation was designed. A central component of this transient elastography system was an arbitrary waveform generator with multi-channel signals output function. This arbitrary waveform generator was used to produce the tissue vibration signal, the ultrasound detection signal and the synchronous triggering signal of the radio frequency data acquisition system. The arbitrary waveform generator can produce different forms of vibration waveform to induce different shear wave propagation in the tissue. Moreover, it can achieve either traditional pulse-echo detection or a phase-modulated or a frequency-modulated coded excitation. A 7-chip Barker code and traditional pulse-echo detection were programmed on the designed ultrasound transient elastography system to detect the shear wave in the phantom excited by the mechanical vibrator. Then an elasticity QA phantom and sixteen in vitro rat livers were used for performance evaluation of the two detection pulses. The elasticity QA phantom's results show that our system is effective, and the rat liver results show the detection depth can be increased more than 1 cm. In addition, the SNR (signal-to-noise ratio) is increased by 15 dB using the 7-chip Barker coded excitation. Applying 7-chip Barker coded excitation technique to the ultrasound transient elastography can increase the detection depth and SNR. Using coded excitation technology to assess the human liver, especially in obese patients, may be a good choice.

  7. Trellis coding techniques for mobile communications

    NASA Technical Reports Server (NTRS)

    Divsalar, D.; Simon, M. K.; Jedrey, T.

    1988-01-01

    A criterion for designing optimum trellis codes to be used over fading channels is given. A technique is shown for reducing certain multiple trellis codes, optimally designed for the fading channel, to conventional (i.e., multiplicity one) trellis codes. The computational cutoff rate R0 is evaluated for MPSK transmitted over fading channels. Examples of trellis codes optimally designed for the Rayleigh fading channel are given and compared with respect to R0. Two types of modulation/demodulation techniques are considered, namely coherent (using pilot tone-aided carrier recovery) and differentially coherent with Doppler frequency correction. Simulation results are given for end-to-end performance of two trellis-coded systems.

  8. Numerical Design of Megawatt Gyrotron with 120 GHz Frequency and 50% Efficiency for Plasma Fusion Application

    NASA Astrophysics Data System (ADS)

    Kumar, Nitin; Singh, Udaybir; Kumar, Anil; Bhattacharya, Ranajoy; Singh, T. P.; Sinha, A. K.

    2013-02-01

    The design of 120 GHz, 1 MW gyrotron for plasma fusion application is presented in this paper. The mode selection is carried out considering the aim of minimum mode competition, minimum cavity wall heating, etc. On the basis of the selected operating mode, the interaction cavity design and beam-wave interaction computation are carried out by using the PIC code. The design of triode type Magnetron Injection Gun (MIG) is also presented. Trajectory code EGUN, synthesis code MIGSYN and data analysis code MIGANS are used in the MIG designing. Further, the design of MIG is also validated by using the another trajectory code TRAK. The design results of beam dumping system (collector) and RF window are also presented. Depressed collector is designed to enhance the overall tube efficiency. The design study confirms >1 MW output power with tube efficiency around 50% (with collector efficiency).

  9. Near Field HF Antenna Pattern Measurement Method Using an Antenna Pattern Range

    DTIC Science & Technology

    2015-12-01

    Year 2015 by the Applied Electromagnetics Branch (Code 52250) of the System of Systems (SoS) & Platform Design Division (Code 52200), Space and...Head SoS & Platform Design Division iii EXECUTIVE SUMMARY The Antenna Pattern Range (APR) is an essential measurement facility operated at Space...14 1 INTRODUCTION Accurate characterization of antennas designed to support the warfighter is a critical

  10. Exploring Type and Amount of Parent Talk during Individualized Family Service Plan Meetings

    ERIC Educational Resources Information Center

    Ridgley, Robyn; Snyder, Patricia; McWilliam, R. A.

    2014-01-01

    We discuss the utility of a coding system designed to evaluate the amount and type of parent talk during individualized family service plan (IFSP) meetings. The iterative processes used to develop the "Parent Communication Coding System" (PCCS) and its associated codes are described. In addition, we explored whether PCCS codes could be…

  11. Creation and utilization of a World Wide Web based space radiation effects code: SIREST

    NASA Technical Reports Server (NTRS)

    Singleterry, R. C. Jr; Wilson, J. W.; Shinn, J. L.; Tripathi, R. K.; Thibeault, S. A.; Noor, A. K.; Cucinotta, F. A.; Badavi, F. F.; Chang, C. K.; Qualls, G. D.; hide

    2001-01-01

    In order for humans and electronics to fully and safely operate in the space environment, codes like HZETRN (High Charge and Energy Transport) must be included in any designer's toolbox for design evaluation with respect to radiation damage. Currently, spacecraft designers do not have easy access to accurate radiation codes like HZETRN to evaluate their design for radiation effects on humans and electronics. Today, the World Wide Web is sophisticated enough to support the entire HZETRN code and all of the associated pre and post processing tools. This package is called SIREST (Space Ionizing Radiation Effects and Shielding Tools). There are many advantages to SIREST. The most important advantage is the instant update capability of the web. Another major advantage is the modularity that the web imposes on the code. Right now, the major disadvantage of SIREST will be its modularity inside the designer's system. This mostly comes from the fact that a consistent interface between the designer and the computer system to evaluate the design is incomplete. This, however, is to be solved in the Intelligent Synthesis Environment (ISE) program currently being funded by NASA.

  12. 77 FR 26672 - Fees for Reviews of the Rule Enforcement Programs of Designated Contract Markets and Registered...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-07

    ... Activity Codes (BPAC) system, formerly the Management Accounting Structure Codes (MASC) system, which... designated contract markets and registered futures associations to recover the costs incurred by the... average of actual program costs incurred during FY 2008, 2009, and 2010. DATES: Effective Date: Each SRO...

  13. Comparison of High-Fidelity Computational Tools for Wing Design of a Distributed Electric Propulsion Aircraft

    NASA Technical Reports Server (NTRS)

    Deere, Karen A.; Viken, Sally A.; Carter, Melissa B.; Viken, Jeffrey K.; Derlaga, Joseph M.; Stoll, Alex M.

    2017-01-01

    A variety of tools, from fundamental to high order, have been used to better understand applications of distributed electric propulsion to aid the wing and propulsion system design of the Leading Edge Asynchronous Propulsion Technology (LEAPTech) project and the X-57 Maxwell airplane. Three high-fidelity, Navier-Stokes computational fluid dynamics codes used during the project with results presented here are FUN3D, STAR-CCM+, and OVERFLOW. These codes employ various turbulence models to predict fully turbulent and transitional flow. Results from these codes are compared for two distributed electric propulsion configurations: the wing tested at NASA Armstrong on the Hybrid-Electric Integrated Systems Testbed truck, and the wing designed for the X-57 Maxwell airplane. Results from these computational tools for the high-lift wing tested on the Hybrid-Electric Integrated Systems Testbed truck and the X-57 high-lift wing presented compare reasonably well. The goal of the X-57 wing and distributed electric propulsion system design achieving or exceeding the required ?? (sub L) = 3.95 for stall speed was confirmed with all of the computational codes.

  14. Piloting a Collaborative Web-Based System for Testing ICD-11.

    PubMed

    Donada, Marc; Kostanjsek, Nenad; Della Mea, Vincenzo; Celik, Can; Jakob, Robert

    2017-01-01

    The 11th revision of the International Classification of Diseases (ICD-11), for the first time in ICD history, deployed web-based collaboration of experts and ICT tools. To ensure that ICD-11 is working well, it needs to be systematically field tested in different settings, across the world. This will be done by means of a number of experiments. In order to support its implementation, a web-based system (ICDfit) has been designed and developed. The present paper illustrates the current prototype of the system and its technical testing. the system has been designed according to WHO requirements, and implemented using PHP and MySQL. Then, a preliminary technical test has been designed and run in January 2016, involving 8 users. They had to carry out double coding, that is, coding case summaries with both ICD-10 and ICD-11, and answering quick questions on the coding difficulty. the 8 users coded 632 cases each, spending an average of 163 seconds per case. While we found an issue in the mechanism used to record coding times, no further issues were found. the proposed system seems to be technically adequate for supporting future ICD-11 testing.

  15. Thermal hydraulic-severe accident code interfaces for SCDAP/RELAP5/MOD3.2

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

    Coryell, E.W.; Siefken, L.J.; Harvego, E.A.

    1997-07-01

    The SCDAP/RELAP5 computer code is designed to describe the overall reactor coolant system thermal-hydraulic response, core damage progression, and fission product release during severe accidents. The code is being developed at the Idaho National Engineering Laboratory under the primary sponsorship of the Office of Nuclear Regulatory Research of the U.S. Nuclear Regulatory Commission. The code is the result of merging the RELAP5, SCDAP, and COUPLE codes. The RELAP5 portion of the code calculates the overall reactor coolant system, thermal-hydraulics, and associated reactor system responses. The SCDAP portion of the code describes the response of the core and associated vessel structures.more » The COUPLE portion of the code describes response of lower plenum structures and debris and the failure of the lower head. The code uses a modular approach with the overall structure, input/output processing, and data structures following the pattern established for RELAP5. The code uses a building block approach to allow the code user to easily represent a wide variety of systems and conditions through a powerful input processor. The user can represent a wide variety of experiments or reactor designs by selecting fuel rods and other assembly structures from a range of representative core component models, and arrange them in a variety of patterns within the thermalhydraulic network. The COUPLE portion of the code uses two-dimensional representations of the lower plenum structures and debris beds. The flow of information between the different portions of the code occurs at each system level time step advancement. The RELAP5 portion of the code describes the fluid transport around the system. These fluid conditions are used as thermal and mass transport boundary conditions for the SCDAP and COUPLE structures and debris beds.« less

  16. Proposing a Web-Based Tutorial System to Teach Malay Language Braille Code to the Sighted

    ERIC Educational Resources Information Center

    Wah, Lee Lay; Keong, Foo Kok

    2010-01-01

    The "e-KodBrailleBM Tutorial System" is a web-based tutorial system which is specially designed to teach, facilitate and support the learning of Malay Language Braille Code to individuals who are sighted. The targeted group includes special education teachers, pre-service teachers, and parents. Learning Braille code involves memorisation…

  17. Single-channel voice-response-system program documentation volume I : system description

    DOT National Transportation Integrated Search

    1977-01-01

    This report documents the design and implementation of a Voice Response System (VRS) using Adaptive Differential Pulse Code Modulation (ADPCM) voice coding. Implemented on a Digital Equipment Corporation PDP-11/20,R this VRS system supports a single ...

  18. Capacity achieving nonbinary LDPC coded non-uniform shaping modulation for adaptive optical communications.

    PubMed

    Lin, Changyu; Zou, Ding; Liu, Tao; Djordjevic, Ivan B

    2016-08-08

    A mutual information inspired nonbinary coded modulation design with non-uniform shaping is proposed. Instead of traditional power of two signal constellation sizes, we design 5-QAM, 7-QAM and 9-QAM constellations, which can be used in adaptive optical networks. The non-uniform shaping and LDPC code rate are jointly considered in the design, which results in a better performance scheme for the same SNR values. The matched nonbinary (NB) LDPC code is used for this scheme, which further improves the coding gain and the overall performance. We analyze both coding performance and system SNR performance. We show that the proposed NB LDPC-coded 9-QAM has more than 2dB gain in symbol SNR compared to traditional LDPC-coded star-8-QAM. On the other hand, the proposed NB LDPC-coded 5-QAM and 7-QAM have even better performance than LDPC-coded QPSK.

  19. Evaluation of three coding schemes designed for improved data communication

    NASA Technical Reports Server (NTRS)

    Snelsire, R. W.

    1974-01-01

    Three coding schemes designed for improved data communication are evaluated. Four block codes are evaluated relative to a quality function, which is a function of both the amount of data rejected and the error rate. The Viterbi maximum likelihood decoding algorithm as a decoding procedure is reviewed. This evaluation is obtained by simulating the system on a digital computer. Short constraint length rate 1/2 quick-look codes are studied, and their performance is compared to general nonsystematic codes.

  20. SCALE: A modular code system for performing Standardized Computer Analyses for Licensing Evaluation. Volume 1, Part 2: Control modules S1--H1; Revision 5

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

    NONE

    SCALE--a modular code system for Standardized Computer Analyses Licensing Evaluation--has been developed by Oak Ridge National Laboratory at the request of the US Nuclear Regulatory Commission. The SCALE system utilizes well-established computer codes and methods within standard analysis sequences that (1) allow an input format designed for the occasional user and/or novice, (2) automated the data processing and coupling between modules, and (3) provide accurate and reliable results. System development has been directed at problem-dependent cross-section processing and analysis of criticality safety, shielding, heat transfer, and depletion/decay problems. Since the initial release of SCALE in 1980, the code system hasmore » been heavily used for evaluation of nuclear fuel facility and package designs. This revision documents Version 4.3 of the system.« less

  1. System optimization on coded aperture spectrometer

    NASA Astrophysics Data System (ADS)

    Liu, Hua; Ding, Quanxin; Wang, Helong; Chen, Hongliang; Guo, Chunjie; Zhou, Liwei

    2017-10-01

    For aim to find a simple multiple configuration solution and achieve higher refractive efficiency, and based on to reduce the situation disturbed by FOV change, especially in a two-dimensional spatial expansion. Coded aperture system is designed by these special structure, which includes an objective a coded component a prism reflex system components, a compensatory plate and an imaging lens Correlative algorithms and perfect imaging methods are available to ensure this system can be corrected and optimized adequately. Simulation results show that the system can meet the application requirements in MTF, REA, RMS and other related criteria. Compared with the conventional design, the system has reduced in volume and weight significantly. Therefore, the determining factors are the prototype selection and the system configuration.

  2. PMD compensation in fiber-optic communication systems with direct detection using LDPC-coded OFDM.

    PubMed

    Djordjevic, Ivan B

    2007-04-02

    The possibility of polarization-mode dispersion (PMD) compensation in fiber-optic communication systems with direct detection using a simple channel estimation technique and low-density parity-check (LDPC)-coded orthogonal frequency division multiplexing (OFDM) is demonstrated. It is shown that even for differential group delay (DGD) of 4/BW (BW is the OFDM signal bandwidth), the degradation due to the first-order PMD can be completely compensated for. Two classes of LDPC codes designed based on two different combinatorial objects (difference systems and product of combinatorial designs) suitable for use in PMD compensation are introduced.

  3. The Modified Cognitive Constructions Coding System: Reliability and Validity Assessments

    ERIC Educational Resources Information Center

    Moran, Galia S.; Diamond, Gary M.

    2006-01-01

    The cognitive constructions coding system (CCCS) was designed for coding client's expressed problem constructions on four dimensions: intrapersonal-interpersonal, internal-external, responsible-not responsible, and linear-circular. This study introduces, and examines the reliability and validity of, a modified version of the CCCS--a version that…

  4. Improving aircraft conceptual design - A PHIGS interactive graphics interface for ACSYNT

    NASA Technical Reports Server (NTRS)

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

    1988-01-01

    A CAD interface has been created for the 'ACSYNT' aircraft conceptual design code that permits the execution and control of the design process via interactive graphics menus. This CAD interface was coded entirely with the new three-dimensional graphics standard, the Programmer's Hierarchical Interactive Graphics System. The CAD/ACSYNT system is designed for use by state-of-the-art high-speed imaging work stations. Attention is given to the approaches employed in modeling, data storage, and rendering.

  5. A New Capability for Nuclear Thermal Propulsion Design

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

    Amiri, Benjamin W.; Nuclear and Radiological Engineering Department, University of Florida, Gainesville, FL 32611; Kapernick, Richard J.

    2007-01-30

    This paper describes a new capability for Nuclear Thermal Propulsion (NTP) design that has been developed, and presents the results of some analyses performed with this design tool. The purpose of the tool is to design to specified mission and material limits, while maximizing system thrust to weight. The head end of the design tool utilizes the ROCket Engine Transient Simulation (ROCETS) code to generate a system design and system design requirements as inputs to the core analysis. ROCETS is a modular system level code which has been used extensively in the liquid rocket engine industry for many years. Themore » core design tool performs high-fidelity reactor core nuclear and thermal-hydraulic design analysis. At the heart of this process are two codes TMSS-NTP and NTPgen, which together greatly automate the analysis, providing the capability to rapidly produce designs that meet all specified requirements while minimizing mass. A PERL based command script, called CORE DESIGNER controls the execution of these two codes, and checks for convergence throughout the process. TMSS-NTP is executed first, to produce a suite of core designs that meet the specified reactor core mechanical, thermal-hydraulic and structural requirements. The suite of designs consists of a set of core layouts and, for each core layout specific designs that span a range of core fuel volumes. NTPgen generates MCNPX models for each of the core designs from TMSS-NTP. Iterative analyses are performed in NTPgen until a reactor design (fuel volume) is identified for each core layout that meets cold and hot operation reactivity requirements and that is zoned to meet a radial core power distribution requirement.« less

  6. Developments in REDES: The rocket engine design expert system

    NASA Technical Reports Server (NTRS)

    Davidian, Kenneth O.

    1990-01-01

    The Rocket Engine Design Expert System (REDES) is being developed at the NASA-Lewis to collect, automate, and perpetuate the existing expertise of performing a comprehensive rocket engine analysis and design. Currently, REDES uses the rigorous JANNAF methodology to analyze the performance of the thrust chamber and perform computational studies of liquid rocket engine problems. The following computer codes were included in REDES: a gas properties program named GASP, a nozzle design program named RAO, a regenerative cooling channel performance evaluation code named RTE, and the JANNAF standard liquid rocket engine performance prediction code TDK (including performance evaluation modules ODE, ODK, TDE, TDK, and BLM). Computational analyses are being conducted by REDES to provide solutions to liquid rocket engine thrust chamber problems. REDES is built in the Knowledge Engineering Environment (KEE) expert system shell and runs on a Sun 4/110 computer.

  7. Developments in REDES: The Rocket Engine Design Expert System

    NASA Technical Reports Server (NTRS)

    Davidian, Kenneth O.

    1990-01-01

    The Rocket Engine Design Expert System (REDES) was developed at NASA-Lewis to collect, automate, and perpetuate the existing expertise of performing a comprehensive rocket engine analysis and design. Currently, REDES uses the rigorous JANNAF methodology to analyze the performance of the thrust chamber and perform computational studies of liquid rocket engine problems. The following computer codes were included in REDES: a gas properties program named GASP; a nozzle design program named RAO; a regenerative cooling channel performance evaluation code named RTE; and the JANNAF standard liquid rocket engine performance prediction code TDK (including performance evaluation modules ODE, ODK, TDE, TDK, and BLM). Computational analyses are being conducted by REDES to provide solutions to liquid rocket engine thrust chamber problems. REDES was built in the Knowledge Engineering Environment (KEE) expert system shell and runs on a Sun 4/110 computer.

  8. Variable Coded Modulation software simulation

    NASA Astrophysics Data System (ADS)

    Sielicki, Thomas A.; Hamkins, Jon; Thorsen, Denise

    This paper reports on the design and performance of a new Variable Coded Modulation (VCM) system. This VCM system comprises eight of NASA's recommended codes from the Consultative Committee for Space Data Systems (CCSDS) standards, including four turbo and four AR4JA/C2 low-density parity-check codes, together with six modulations types (BPSK, QPSK, 8-PSK, 16-APSK, 32-APSK, 64-APSK). The signaling protocol for the transmission mode is based on a CCSDS recommendation. The coded modulation may be dynamically chosen, block to block, to optimize throughput.

  9. Organizational Effectiveness Information System (OEIS) User’s Manual

    DTIC Science & Technology

    1986-09-01

    SUBJECT CODES B-l C. LISTING OF VALID RESOURCE SYSTEM CODES C-l »TflerÄ*w»fi*%f*fc**v.nft; ^’.A/.V. A y.A/.AAA«•.*-A/. AAV ...the valid codes used la the Implementation and Design System. MACOM 01 COE 02 DARCOM 03 EUSA 04 FORSCOM 05 HSC 06 HQDA 07 INSCOM 08 MDW 09

  10. National Electrical Code in Power Engineering Course for Electrical Engineering Curriculum

    ERIC Educational Resources Information Center

    Azizur, Rahman M. M.

    2011-01-01

    In order to ensure the safety of their inhabitants and properties, the residential, industrial and business installations require complying with NEC (national electrical code) for electrical systems. Electrical design engineers and technicians rely heavily on these very important design guidelines. However, these design guidelines are not formally…

  11. GSE, data management system programmers/User' manual

    NASA Technical Reports Server (NTRS)

    Schlagheck, R. A.; Dolerhie, B. D., Jr.; Ghiglieri, F. J.

    1974-01-01

    The GSE data management system is a computerized program which provides for a central storage source for key data associated with the mechanical ground support equipment (MGSE). Eight major sort modes can be requested by the user. Attributes that are printed automatically with each sort include the GSE end item number, description, class code, functional code, fluid media, use location, design responsibility, weight, cost, quantity, dimensions, and applicable documents. Multiple subsorts are available for the class code, functional code, fluid media, use location, design responsibility, and applicable document categories. These sorts and how to use them are described. The program and GSE data bank may be easily updated and expanded.

  12. Numerical, Analytical, Experimental Study of Fluid Dynamic Forces in Seals Volume 6: Description of Scientific CFD Code SCISEAL

    NASA Technical Reports Server (NTRS)

    Athavale, Mahesh; Przekwas, Andrzej

    2004-01-01

    The objectives of the program were to develop computational fluid dynamics (CFD) codes and simpler industrial codes for analyzing and designing advanced seals for air-breathing and space propulsion engines. The CFD code SCISEAL is capable of producing full three-dimensional flow field information for a variety of cylindrical configurations. An implicit multidomain capability allow the division of complex flow domains to allow optimum use of computational cells. SCISEAL also has the unique capability to produce cross-coupled stiffness and damping coefficients for rotordynamic computations. The industrial codes consist of a series of separate stand-alone modules designed for expeditious parametric analyses and optimization of a wide variety of cylindrical and face seals. Coupled through a Knowledge-Based System (KBS) that provides a user-friendly Graphical User Interface (GUI), the industrial codes are PC based using an OS/2 operating system. These codes were designed to treat film seals where a clearance exists between the rotating and stationary components. Leakage is inhibited by surface roughness, small but stiff clearance films, and viscous pumping devices. The codes have demonstrated to be a valuable resource for seal development of future air-breathing and space propulsion engines.

  13. Extending the Capture Volume of an Iris Recognition System Using Wavefront Coding and Super-Resolution.

    PubMed

    Hsieh, Sheng-Hsun; Li, Yung-Hui; Tien, Chung-Hao; Chang, Chin-Chen

    2016-12-01

    Iris recognition has gained increasing popularity over the last few decades; however, the stand-off distance in a conventional iris recognition system is too short, which limits its application. In this paper, we propose a novel hardware-software hybrid method to increase the stand-off distance in an iris recognition system. When designing the system hardware, we use an optimized wavefront coding technique to extend the depth of field. To compensate for the blurring of the image caused by wavefront coding, on the software side, the proposed system uses a local patch-based super-resolution method to restore the blurred image to its clear version. The collaborative effect of the new hardware design and software post-processing showed great potential in our experiment. The experimental results showed that such improvement cannot be achieved by using a hardware-or software-only design. The proposed system can increase the capture volume of a conventional iris recognition system by three times and maintain the system's high recognition rate.

  14. National Combustion Code Parallel Performance Enhancements

    NASA Technical Reports Server (NTRS)

    Quealy, Angela; Benyo, Theresa (Technical Monitor)

    2002-01-01

    The National Combustion Code (NCC) is being developed by an industry-government team for the design and analysis of combustion systems. The unstructured grid, reacting flow code uses a distributed memory, message passing model for its parallel implementation. The focus of the present effort has been to improve the performance of the NCC code to meet combustor designer requirements for model accuracy and analysis turnaround time. Improving the performance of this code contributes significantly to the overall reduction in time and cost of the combustor design cycle. This report describes recent parallel processing modifications to NCC that have improved the parallel scalability of the code, enabling a two hour turnaround for a 1.3 million element fully reacting combustion simulation on an SGI Origin 2000.

  15. The development of a thermal hydraulic feedback mechanism with a quasi-fixed point iteration scheme for control rod position modeling for the TRIGSIMS-TH application

    NASA Astrophysics Data System (ADS)

    Karriem, Veronica V.

    Nuclear reactor design incorporates the study and application of nuclear physics, nuclear thermal hydraulic and nuclear safety. Theoretical models and numerical methods implemented in computer programs are utilized to analyze and design nuclear reactors. The focus of this PhD study's is the development of an advanced high-fidelity multi-physics code system to perform reactor core analysis for design and safety evaluations of research TRIGA-type reactors. The fuel management and design code system TRIGSIMS was further developed to fulfill the function of a reactor design and analysis code system for the Pennsylvania State Breazeale Reactor (PSBR). TRIGSIMS, which is currently in use at the PSBR, is a fuel management tool, which incorporates the depletion code ORIGEN-S (part of SCALE system) and the Monte Carlo neutronics solver MCNP. The diffusion theory code ADMARC-H is used within TRIGSIMS to accelerate the MCNP calculations. It manages the data and fuel isotopic content and stores it for future burnup calculations. The contribution of this work is the development of an improved version of TRIGSIMS, named TRIGSIMS-TH. TRIGSIMS-TH incorporates a thermal hydraulic module based on the advanced sub-channel code COBRA-TF (CTF). CTF provides the temperature feedback needed in the multi-physics calculations as well as the thermal hydraulics modeling capability of the reactor core. The temperature feedback model is using the CTF-provided local moderator and fuel temperatures for the cross-section modeling for ADMARC-H and MCNP calculations. To perform efficient critical control rod calculations, a methodology for applying a control rod position was implemented in TRIGSIMS-TH, making this code system a modeling and design tool for future core loadings. The new TRIGSIMS-TH is a computer program that interlinks various other functional reactor analysis tools. It consists of the MCNP5, ADMARC-H, ORIGEN-S, and CTF. CTF was coupled with both MCNP and ADMARC-H to provide the heterogeneous temperature distribution throughout the core. Each of these codes is written in its own computer language performing its function and outputs a set of data. TRIGSIMS-TH provides an effective use and data manipulation and transfer between different codes. With the implementation of feedback and control- rod-position modeling methodologies, the TRIGSIMS-TH calculations are more accurate and in a better agreement with measured data. The PSBR is unique in many ways and there are no "off-the-shelf" codes, which can model this design in its entirety. In particular, PSBR has an open core design, which is cooled by natural convection. Combining several codes into a unique system brings many challenges. It also requires substantial knowledge of both operation and core design of the PSBR. This reactor is in operation decades and there is a fair amount of studies and developments in both PSBR thermal hydraulics and neutronics. Measured data is also available for various core loadings and can be used for validation activities. The previous studies and developments in PSBR modeling also aids as a guide to assess the findings of the work herein. In order to incorporate new methods and codes into exiting TRIGSIMS, a re-evaluation of various components of the code was performed to assure the accuracy and efficiency of the existing CTF/MCNP5/ADMARC-H multi-physics coupling. A new set of ADMARC-H diffusion coefficients and cross sections was generated using the SERPENT code. This was needed as the previous data was not generated with thermal hydraulic feedback and the ARO position was used as the critical rod position. The B4C was re-evaluated for this update. The data exchange between ADMARC-H and MCNP5 was modified. The basic core model is given a flexibility to allow for various changes within the core model, and this feature was implemented in TRIGSIMS-TH. The PSBR core in the new code model can be expanded and changed. This allows the new code to be used as a modeling tool for design and analyses of future code loadings.

  16. Evaluating the performance of two neutron spectrum unfolding codes based on iterative procedures and artificial neural networks

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

    Ortiz-Rodriguez, J. M.; Reyes Alfaro, A.; Reyes Haro, A.

    In this work the performance of two neutron spectrum unfolding codes based on iterative procedures and artificial neural networks is evaluated. The first one code based on traditional iterative procedures and called Neutron spectrometry and dosimetry from the Universidad Autonoma de Zacatecas (NSDUAZ) use the SPUNIT iterative algorithm and was designed to unfold neutron spectrum and calculate 15 dosimetric quantities and 7 IAEA survey meters. The main feature of this code is the automated selection of the initial guess spectrum trough a compendium of neutron spectrum compiled by the IAEA. The second one code known as Neutron spectrometry and dosimetrymore » with artificial neural networks (NDSann) is a code designed using neural nets technology. The artificial intelligence approach of neural net does not solve mathematical equations. By using the knowledge stored at synaptic weights on a neural net properly trained, the code is capable to unfold neutron spectrum and to simultaneously calculate 15 dosimetric quantities, needing as entrance data, only the rate counts measured with a Bonner spheres system. Similarities of both NSDUAZ and NSDann codes are: they follow the same easy and intuitive user's philosophy and were designed in a graphical interface under the LabVIEW programming environment. Both codes unfold the neutron spectrum expressed in 60 energy bins, calculate 15 dosimetric quantities and generate a full report in HTML format. Differences of these codes are: NSDUAZ code was designed using classical iterative approaches and needs an initial guess spectrum in order to initiate the iterative procedure. In NSDUAZ, a programming routine was designed to calculate 7 IAEA instrument survey meters using the fluence-dose conversion coefficients. NSDann code use artificial neural networks for solving the ill-conditioned equation system of neutron spectrometry problem through synaptic weights of a properly trained neural network. Contrary to iterative procedures, in neural net approach it is possible to reduce the rate counts used to unfold the neutron spectrum. To evaluate these codes a computer tool called Neutron Spectrometry and dosimetry computer tool was designed. The results obtained with this package are showed. The codes here mentioned are freely available upon request to the authors.« less

  17. Evaluating the performance of two neutron spectrum unfolding codes based on iterative procedures and artificial neural networks

    NASA Astrophysics Data System (ADS)

    Ortiz-Rodríguez, J. M.; Reyes Alfaro, A.; Reyes Haro, A.; Solís Sánches, L. O.; Miranda, R. Castañeda; Cervantes Viramontes, J. M.; Vega-Carrillo, H. R.

    2013-07-01

    In this work the performance of two neutron spectrum unfolding codes based on iterative procedures and artificial neural networks is evaluated. The first one code based on traditional iterative procedures and called Neutron spectrometry and dosimetry from the Universidad Autonoma de Zacatecas (NSDUAZ) use the SPUNIT iterative algorithm and was designed to unfold neutron spectrum and calculate 15 dosimetric quantities and 7 IAEA survey meters. The main feature of this code is the automated selection of the initial guess spectrum trough a compendium of neutron spectrum compiled by the IAEA. The second one code known as Neutron spectrometry and dosimetry with artificial neural networks (NDSann) is a code designed using neural nets technology. The artificial intelligence approach of neural net does not solve mathematical equations. By using the knowledge stored at synaptic weights on a neural net properly trained, the code is capable to unfold neutron spectrum and to simultaneously calculate 15 dosimetric quantities, needing as entrance data, only the rate counts measured with a Bonner spheres system. Similarities of both NSDUAZ and NSDann codes are: they follow the same easy and intuitive user's philosophy and were designed in a graphical interface under the LabVIEW programming environment. Both codes unfold the neutron spectrum expressed in 60 energy bins, calculate 15 dosimetric quantities and generate a full report in HTML format. Differences of these codes are: NSDUAZ code was designed using classical iterative approaches and needs an initial guess spectrum in order to initiate the iterative procedure. In NSDUAZ, a programming routine was designed to calculate 7 IAEA instrument survey meters using the fluence-dose conversion coefficients. NSDann code use artificial neural networks for solving the ill-conditioned equation system of neutron spectrometry problem through synaptic weights of a properly trained neural network. Contrary to iterative procedures, in neural net approach it is possible to reduce the rate counts used to unfold the neutron spectrum. To evaluate these codes a computer tool called Neutron Spectrometry and dosimetry computer tool was designed. The results obtained with this package are showed. The codes here mentioned are freely available upon request to the authors.

  18. Design and implementation of encrypted and decrypted file system based on USBKey and hardware code

    NASA Astrophysics Data System (ADS)

    Wu, Kehe; Zhang, Yakun; Cui, Wenchao; Jiang, Ting

    2017-05-01

    To protect the privacy of sensitive data, an encrypted and decrypted file system based on USBKey and hardware code is designed and implemented in this paper. This system uses USBKey and hardware code to authenticate a user. We use random key to encrypt file with symmetric encryption algorithm and USBKey to encrypt random key with asymmetric encryption algorithm. At the same time, we use the MD5 algorithm to calculate the hash of file to verify its integrity. Experiment results show that large files can be encrypted and decrypted in a very short time. The system has high efficiency and ensures the security of documents.

  19. Gamma irradiator dose mapping simulation using the MCNP code and benchmarking with dosimetry.

    PubMed

    Sohrabpour, M; Hassanzadeh, M; Shahriari, M; Sharifzadeh, M

    2002-10-01

    The Monte Carlo transport code, MCNP, has been applied in simulating dose rate distribution in the IR-136 gamma irradiator system. Isodose curves, cumulative dose values, and system design data such as throughputs, over-dose-ratios, and efficiencies have been simulated as functions of product density. Simulated isodose curves, and cumulative dose values were compared with dosimetry values obtained using polymethyle-methacrylate, Fricke, ethanol-chlorobenzene, and potassium dichromate dosimeters. The produced system design data were also found to agree quite favorably with those of the system manufacturer's data. MCNP has thus been found to be an effective transport code for handling of various dose mapping excercises for gamma irradiators.

  20. Combined trellis coding with asymmetric MPSK modulation: An MSAT-X report

    NASA Technical Reports Server (NTRS)

    Simon, M. K.; Divsalar, D.

    1985-01-01

    Traditionally symmetric, multiple phase-shift-keyed (MPSK) signal constellations, i.e., those with uniformly spaced signal points around the circle, have been used for both uncoded and coded systems. Although symmetric MPSK signal constellations are optimum for systems with no coding, the same is not necessarily true for coded systems. This appears to show that by designing the signal constellations to be asymmetric, one can, in many instances, obtain a significant performance improvement over the traditional symmetric MPSK constellations combined with trellis coding. The joint design of n/(n + 1) trellis codes and asymmetric 2 sup n + 1 - point MPSK is considered, which has a unity bandwidth expansion relative to uncoded 2 sup n-point symmetric MPSK. The asymptotic performance gains due to coding and asymmetry are evaluated in terms of the minimum free Euclidean distance free of the trellis. A comparison of the maximum value of this performance measure with the minimum distance d sub min of the uncoded system is an indication of the maximum reduction in required E sub b/N sub O that can be achieved for arbitrarily small system bit-error rates. It is to be emphasized that the introduction of asymmetry into the signal set does not effect the bandwidth of power requirements of the system; hence, the above-mentioned improvements in performance come at little or no cost. MPSK signal sets in coded systems appear in the work of Divsalar.

  1. Acquisition Handbook - Update. Comprehensive Approach to Reusable Defensive Software (CARDS)

    DTIC Science & Technology

    1994-03-25

    designs, and implementation components (source code, test plans, procedures and results, and system/software documentation). This handbook provides a...activities where software components are acquired, evaluated, tested and sometimes modified. In addition to serving as a facility for the acquisition and...systems from such components [1]. Implementation components are at the lowest level and consist of: specifications; detailed designs; code, test

  2. DataRocket: Interactive Visualisation of Data Structures

    NASA Astrophysics Data System (ADS)

    Parkes, Steve; Ramsay, Craig

    2010-08-01

    CodeRocket is a software engineering tool that provides cognitive support to the software engineer for reasoning about a method or procedure and for documenting the resulting code [1]. DataRocket is a software engineering tool designed to support visualisation and reasoning about program data structures. DataRocket is part of the CodeRocket family of software tools developed by Rapid Quality Systems [2] a spin-out company from the Space Technology Centre at the University of Dundee. CodeRocket and DataRocket integrate seamlessly with existing architectural design and coding tools and provide extensive documentation with little or no effort on behalf of the software engineer. Comprehensive, abstract, detailed design documentation is available early on in a project so that it can be used for design reviews with project managers and non expert stakeholders. Code and documentation remain fully synchronised even when changes are implemented in the code without reference to the existing documentation. At the end of a project the press of a button suffices to produce the detailed design document. Existing legacy code can be easily imported into CodeRocket and DataRocket to reverse engineer detailed design documentation making legacy code more manageable and adding substantially to its value. This paper introduces CodeRocket. It then explains the rationale for DataRocket and describes the key features of this new tool. Finally the major benefits of DataRocket for different stakeholders are considered.

  3. Return Difference Feedback Design for Robust Uncertainty Tolerance in Stochastic Multivariable Control Systems.

    DTIC Science & Technology

    1982-11-01

    D- R136 495 RETURN DIFFERENCE FEEDBACK DESIGN FOR ROBUSTj/ UNCERTAINTY TOLERANCE IN STO..(U) UNIVERSITY OF SOUTHERN CALIFORNIA LOS ANGELES DEPT OF...State and ZIP Code) 7. b6 ADORESS (City. Staft and ZIP Code) Department of Electrical Engineering -’M Directorate of Mathematical & Information Systems ...13. SUBJECT TERMS Continur on rverse ineeesaty and identify by block nmber) FIELD GROUP SUE. GR. Systems theory; control; feedback; automatic control

  4. Coordinated design of coding and modulation systems

    NASA Technical Reports Server (NTRS)

    Massey, J. L.

    1976-01-01

    Work on partial unit memory codes continued; it was shown that for a given virtual state complexity, the maximum free distance over the class of all convolutional codes is achieved within the class of unit memory codes. The effect of phase-lock loop (PLL) tracking error on coding system performance was studied by using the channel cut-off rate as the measure of quality of a modulation system. Optimum modulation signal sets for a non-white Gaussian channel considered an heuristic selection rule based on a water-filling argument. The use of error correcting codes to perform data compression by the technique of syndrome source coding was researched and a weight-and-error-locations scheme was developed that is closely related to LDSC coding.

  5. A New Design Method of Automotive Electronic Real-time Control System

    NASA Astrophysics Data System (ADS)

    Zuo, Wenying; Li, Yinguo; Wang, Fengjuan; Hou, Xiaobo

    Structure and functionality of automotive electronic control system is becoming more and more complex. The traditional manual programming development mode to realize automotive electronic control system can't satisfy development needs. So, in order to meet diversity and speedability of development of real-time control system, combining model-based design approach and auto code generation technology, this paper proposed a new design method of automotive electronic control system based on Simulink/RTW. Fristly, design algorithms and build a control system model in Matlab/Simulink. Then generate embedded code automatically by RTW and achieve automotive real-time control system development in OSEK/VDX operating system environment. The new development mode can significantly shorten the development cycle of automotive electronic control system, improve program's portability, reusability and scalability and had certain practical value for the development of real-time control system.

  6. TFaNS Tone Fan Noise Design/Prediction System. Volume 3; Evaluation of System Codes

    NASA Technical Reports Server (NTRS)

    Topol, David A.

    1999-01-01

    TFANS is the Tone Fan Noise Design/Prediction System developed by Pratt & Whitney under contract to NASA Lewis (presently NASA Glenn). The purpose of this system is to predict tone noise emanating from a fan stage including the effects of reflection and transmission by the rotor and stator and by the duct inlet and nozzle. These effects have been added to an existing annular duct/isolated stator noise prediction capability. TFANS consists of: The codes that compute the acoustic properties (reflection and transmission coefficients) of the various elements and write them to files. Cup3D: Fan Noise Coupling Code that reads these files, solves the coupling problem, and outputs the desired noise predictions. AWAKEN: CFD/Measured Wake Postprocessor which reformats CFD wake predictions and/or measured wake data so it can be used by the system. This volume of the report evaluates TFANS versus full-scale and ADP 22" fig data using the semi-empirical wake modelling in the system. This report is divided into three volumes: Volume 1: System Description, CUP3D Technical Documentation, and Manual for Code Developers; Volume II: User's Manual, TFANS Version 1.4; Volume III: Evaluation of System Codes.

  7. ANL/RBC: A computer code for the analysis of Rankine bottoming cycles, including system cost evaluation and off-design performance

    NASA Technical Reports Server (NTRS)

    Mclennan, G. A.

    1986-01-01

    This report describes, and is a User's Manual for, a computer code (ANL/RBC) which calculates cycle performance for Rankine bottoming cycles extracting heat from a specified source gas stream. The code calculates cycle power and efficiency and the sizes for the heat exchangers, using tabular input of the properties of the cycle working fluid. An option is provided to calculate the costs of system components from user defined input cost functions. These cost functions may be defined in equation form or by numerical tabular data. A variety of functional forms have been included for these functions and they may be combined to create very general cost functions. An optional calculation mode can be used to determine the off-design performance of a system when operated away from the design-point, using the heat exchanger areas calculated for the design-point.

  8. RELAP-7 Software Verification and Validation Plan

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

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

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

  9. Design of a recovery system for a reentry vehicle

    NASA Technical Reports Server (NTRS)

    Von Eckroth, Wulf; Garrard, William L.; Miller, Norman

    1993-01-01

    Engineers are often required to design decelerator systems which are deployed in cross-wind orientations. If the system is not designed to minimize 'line sail', damage to the parachutes could result. A Reentry Vehicle Analysis Code (RVAC) and an accompanying graphics animation software program (DISPLAY) are presented in this paper. These computer codes allow the user to quickly apply the Purvis line sail modeling technique to any vehicle and then observe the relative motion of the vehicle, nose cap, suspension lines, pilot and drogue bags and canopies on a computer screen. Data files are created which allow plots of velocities, spacial positions, and dynamic pressures versus time to be generated. The code is an important tool for the design engineer because it integrates two degrees of freedom (DOF) line sail equations with a three DOF model of the reentry body and jettisoned nose cap to provide an animated output.

  10. Design and implementation of H.264 based embedded video coding technology

    NASA Astrophysics Data System (ADS)

    Mao, Jian; Liu, Jinming; Zhang, Jiemin

    2016-03-01

    In this paper, an embedded system for remote online video monitoring was designed and developed to capture and record the real-time circumstances in elevator. For the purpose of improving the efficiency of video acquisition and processing, the system selected Samsung S5PV210 chip as the core processor which Integrated graphics processing unit. And the video was encoded with H.264 format for storage and transmission efficiently. Based on S5PV210 chip, the hardware video coding technology was researched, which was more efficient than software coding. After running test, it had been proved that the hardware video coding technology could obviously reduce the cost of system and obtain the more smooth video display. It can be widely applied for the security supervision [1].

  11. A Response Surface Methodology for Bi-Level Integrated System Synthesis (BLISS)

    NASA Technical Reports Server (NTRS)

    Altus, Troy David; Sobieski, Jaroslaw (Technical Monitor)

    2002-01-01

    The report describes a new method for optimization of engineering systems such as aerospace vehicles whose design must harmonize a number of subsystems and various physical phenomena, each represented by a separate computer code, e.g., aerodynamics, structures, propulsion, performance, etc. To represent the system internal couplings, the codes receive output from other codes as part of their inputs. The system analysis and optimization task is decomposed into subtasks that can be executed concurrently, each subtask conducted using local state and design variables and holding constant a set of the system-level design variables. The subtasks results are stored in form of the Response Surfaces (RS) fitted in the space of the system-level variables to be used as the subtask surrogates in a system-level optimization whose purpose is to optimize the system objective(s) and to reconcile the system internal couplings. By virtue of decomposition and execution concurrency, the method enables a broad workfront in organization of an engineering project involving a number of specialty groups that might be geographically dispersed, and it exploits the contemporary computing technology of massively concurrent and distributed processing. The report includes a demonstration test case of supersonic business jet design.

  12. Heart Pump Design for Cleveland Clinic Foundation

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Through a Lewis CommTech Program project with the Cleveland Clinic Foundation, the NASA Lewis Research Center is playing a key role in the design and development of a permanently implantable, artificial heart pump assist device. Known as the Innovative Ventricular Assist System (IVAS), this device will take on the pumping role of the damaged left ventricle of the heart. The key part of the IVAS is a nonpulsatile (continuous flow) artificial heart pump with centrifugal impeller blades, driven by an electric motor. Lewis is part of an industry and academia team, led by the Ohio Aerospace Institute (OAI), that is working with the Cleveland Clinic Foundation to make IVAS a reality. This device has the potential to save tens of thousands of lives each year, since 80 percent of heart attack victims suffer irreversible damage to the left ventricle, the part of the heart that does most of the pumping. Impeller blade design codes and flow-modeling analytical codes will be used in the project. These codes were developed at Lewis for the aerospace industry but will be applicable to the IVAS design project. The analytical codes, which currently simulate the flow through the compressor and pump systems, will be used to simulate the flow within the blood pump in the artificial heart assist device. The Interdisciplinary Technology Office heads up Lewis' efforts in the IVAS project. With the aid of numerical modeling, the blood pump will address many design issues, including some fluid-dynamic design considerations that are unique to the properties of blood. Some of the issues that will be addressed in the design process include hemolysis, deposition, recirculation, pump efficiency, rotor thrust balance, and bearing lubrication. Optimum pumping system performance will be achieved by modeling all the interactions between the pump components. The interactions can be multidisciplinary and, therefore, are influenced not only by the fluid dynamics of adjacent components but also by thermal and structural effects. Lewis-developed flow-modeling codes to be used in the pump simulations will include a one-dimensional code and an incompressible three-dimensional Navier-Stokes flow code. These codes will analyze the prototype pump designed by the Cleveland Clinic Foundation. With an improved understanding of the flow phenomena within the prototype pump, design changes to improve the performance of the pump system can be verified by computer prior to fabrication in order to reduce risks. The use of Lewis flow modeling codes during the design and development process will improve pump system performance and reduce the number of prototypes built in the development phase. The first phase of the IVAS project is to fully develop the prototype in a laboratory environment that uses a water/glycerin mixture as the surrogate fluid to simulate blood. A later phase of the project will include testing in animals for final validation. Lewis will be involved in the IVAS project for 3 to 5 years.

  13. 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.

  14. Dynamic response analysis of a 24-story damped steel structure

    NASA Astrophysics Data System (ADS)

    Feng, Demin; Miyama, Takafumi

    2017-10-01

    In Japanese and Chinese building codes, a two-stage design philosophy, damage limitation (small earthquake, Level 1) and life safety (extreme large earthquake, Level 2), is adopted. It is very interesting to compare the design method of a damped structure based on the two building codes. In the Chinese code, in order to be consistent with the conventional seismic design method, the damped structure is also designed at the small earthquake level. The effect of damper systems is considered by the additional damping ratio concept. The design force will be obtained from the damped design spectrum considering the reduction due to the additional damping ratio. The additional damping ratio by the damper system is usually calculated by a time history analysis method at the small earthquake level. The velocity dependent type dampers such as viscous dampers can function well even in the small earthquake level. But, if steel damper is used, which usually remains elastic in the small earthquake, there will be no additional damping ratio achieved. On the other hand, a time history analysis is used in Japan both for small earthquake and extreme large earthquake level. The characteristics of damper system and ductility of the structure can be modelled well. An existing 24-story steel frame is modified to demonstrate the design process of the damped structure based on the two building codes. Viscous wall type damper and low yield steel panel dampers are studied as the damper system.

  15. The performance of trellis coded multilevel DPSK on a fading mobile satellite channel

    NASA Technical Reports Server (NTRS)

    Simon, Marvin K.; Divsalar, Dariush

    1987-01-01

    The performance of trellis coded multilevel differential phase-shift-keying (MDPSK) over Rician and Rayleigh fading channels is discussed. For operation at L-Band, this signalling technique leads to a more robust system than the coherent system with dual pilot tone calibration previously proposed for UHF. The results are obtained using a combination of analysis and simulation. The analysis shows that the design criterion for trellis codes to be operated on fading channels with interleaving/deinterleaving is no longer free Euclidean distance. The correct design criterion for optimizing bit error probability of trellis coded MDPSK over fading channels will be presented along with examples illustrating its application.

  16. Verification and Validation in a Rapid Software Development Process

    NASA Technical Reports Server (NTRS)

    Callahan, John R.; Easterbrook, Steve M.

    1997-01-01

    The high cost of software production is driving development organizations to adopt more automated design and analysis methods such as rapid prototyping, computer-aided software engineering (CASE) tools, and high-level code generators. Even developers of safety-critical software system have adopted many of these new methods while striving to achieve high levels Of quality and reliability. While these new methods may enhance productivity and quality in many cases, we examine some of the risks involved in the use of new methods in safety-critical contexts. We examine a case study involving the use of a CASE tool that automatically generates code from high-level system designs. We show that while high-level testing on the system structure is highly desirable, significant risks exist in the automatically generated code and in re-validating releases of the generated code after subsequent design changes. We identify these risks and suggest process improvements that retain the advantages of rapid, automated development methods within the quality and reliability contexts of safety-critical projects.

  17. Multi-level of Fidelity Multi-Disciplinary Design Optimization of Small, Solid-Propellant Launch Vehicles

    NASA Astrophysics Data System (ADS)

    Roshanian, Jafar; Jodei, Jahangir; Mirshams, Mehran; Ebrahimi, Reza; Mirzaee, Masood

    A new automated multi-level of fidelity Multi-Disciplinary Design Optimization (MDO) methodology has been developed at the MDO Laboratory of K.N. Toosi University of Technology. This paper explains a new design approach by formulation of developed disciplinary modules. A conceptual design for a small, solid-propellant launch vehicle was considered at two levels of fidelity structure. Low and medium level of fidelity disciplinary codes were developed and linked. Appropriate design and analysis codes were defined according to their effect on the conceptual design process. Simultaneous optimization of the launch vehicle was performed at the discipline level and system level. Propulsion, aerodynamics, structure and trajectory disciplinary codes were used. To reach the minimum launch weight, the Low LoF code first searches the whole design space to achieve the mission requirements. Then the medium LoF code receives the output of the low LoF and gives a value near the optimum launch weight with more details and higher fidelity.

  18. Manual for the Student Attributes Coding System.

    ERIC Educational Resources Information Center

    Brophy, Jere E.; And Others

    The Student Attributes Coding System has been developed for gathering data about the personal characteristics and classroom behavior of elementary school students selected for observation because they engender predictable attitudes and expectations in their teachers. This system is designed to systematically record and categorize all interactions…

  19. Application of a Design Space Exploration Tool to Enhance Interleaver Generation

    DTIC Science & Technology

    2009-06-24

    2], originally dedicated to channel coding, are being currently reused in a large set of the whole digital communication systems (e.g. equalization... originally target interface synthesis, is shown to be also suited to the interleaver design space exploration. Our design flow can take as input...slice turbo codes,” in Proc. 3rd Int. Symp. Turbo Codes, Related Topics, Brest , 2003, pp. 343–346. [11] IEEE 802.15.3a, WPAN High Rate Alternative [12

  20. Diversity-optimal power loading for intensity modulated MIMO optical wireless communications.

    PubMed

    Zhang, Yan-Yu; Yu, Hong-Yi; Zhang, Jian-Kang; Zhu, Yi-Jun

    2016-04-18

    In this paper, we consider the design of space code for an intensity modulated direct detection multi-input-multi-output optical wireless communication (IM/DD MIMO-OWC) system, in which channel coefficients are independent and non-identically log-normal distributed, with variances and means known at the transmitter and channel state information available at the receiver. Utilizing the existing space code design criterion for IM/DD MIMO-OWC with a maximum likelihood (ML) detector, we design a diversity-optimal space code (DOSC) that maximizes both large-scale diversity and small-scale diversity gains and prove that the spatial repetition code (RC) with a diversity-optimized power allocation is diversity-optimal among all the high dimensional nonnegative space code schemes under a commonly used optical power constraint. In addition, we show that one of significant advantages of the DOSC is to allow low-complexity ML detection. Simulation results indicate that in high signal-to-noise ratio (SNR) regimes, our proposed DOSC significantly outperforms RC, which is the best space code currently available for such system.

  1. Design applications for supercomputers

    NASA Technical Reports Server (NTRS)

    Studerus, C. J.

    1987-01-01

    The complexity of codes for solutions of real aerodynamic problems has progressed from simple two-dimensional models to three-dimensional inviscid and viscous models. As the algorithms used in the codes increased in accuracy, speed and robustness, the codes were steadily incorporated into standard design processes. The highly sophisticated codes, which provide solutions to the truly complex flows, require computers with large memory and high computational speed. The advent of high-speed supercomputers, such that the solutions of these complex flows become more practical, permits the introduction of the codes into the design system at an earlier stage. The results of several codes which either were already introduced into the design process or are rapidly in the process of becoming so, are presented. The codes fall into the area of turbomachinery aerodynamics and hypersonic propulsion. In the former category, results are presented for three-dimensional inviscid and viscous flows through nozzle and unducted fan bladerows. In the latter category, results are presented for two-dimensional inviscid and viscous flows for hypersonic vehicle forebodies and engine inlets.

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

    NASA Technical Reports Server (NTRS)

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

    1991-01-01

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

  3. The Development of a Programming Support System for Rapid Prototyping. Tasks 2 and 3.

    DTIC Science & Technology

    1985-01-01

    of the problems that played a role in the larger system. The principal work in Task 2 was the design of a new method for code-generation...develop- Ing a prototype of the interpreter. Due to the limitation of funds, only a design , not a prototype of the bi-directional l 2 scanner was...Introduction LiTmitUn uupii The Problem of designing a code generator for an interpreter-based languae Jas provided a chance to reoexamine fth

  4. Coupled Analysis of an Inlet and Fan for a Quiet Supersonic Aircraft

    NASA Technical Reports Server (NTRS)

    Chima, Rodrick V.; Conners, Timothy R.; Wayman, Thomas R.

    2009-01-01

    A computational analysis of a Gulfstream isentropic external compression supersonic inlet coupled to a Rolls-Royce fan was completed. The inlet was designed for a small, low sonic boom supersonic vehicle with a design cruise condition of M = 1.6 at 45,000 feet. The inlet design included an annular bypass duct that routed flow subsonically around an engine-mounted gearbox and diverted flow with high shock losses away from the fan tip. Two Reynolds-averaged Navier-Stokes codes were used for the analysis: an axisymmetric code called AVCS for the inlet and a 3-D code called SWIFT for the fan. The codes were coupled at a mixing plane boundary using a separate code for data exchange. The codes were used to determine the performance of the inlet/fan system at the design point and to predict the performance and operability of the system over the flight profile. At the design point the core inlet had a recovery of 96 percent, and the fan operated near its peak efficiency and pressure ratio. A large hub radial distortion generated in the inlet was not eliminated by the fan and could pose a challenge for subsequent booster stages. The system operated stably at all points along the flight profile. Reduced stall margin was seen at low altitude and Mach number where flow separated on the interior lips of the cowl and bypass ducts. The coupled analysis gave consistent solutions at all points on the flight profile that would be difficult or impossible to predict by analysis of isolated components.

  5. Coupled Analysis of an Inlet and Fan for a Quiet Supersonic Jet

    NASA Technical Reports Server (NTRS)

    Chima, Rodrick V.; Conners, Timothy R.; Wayman, Thomas R.

    2010-01-01

    A computational analysis of a Gulfstream isentropic external compression supersonic inlet coupled to a Rolls-Royce fan has been completed. The inlet was designed for a small, low sonic boom supersonic vehicle with a design cruise condition of M = 1.6 at 45,000 ft. The inlet design included an annular bypass duct that routed flow subsonically around an engine-mounted gearbox and diverted flow with high shock losses away from the fan tip. Two Reynolds-averaged Navier-Stokes codes were used for the analysis: an axisymmetric code called AVCS for the inlet and a three dimensional (3-D) code called SWIFT for the fan. The codes were coupled at a mixing plane boundary using a separate code for data exchange. The codes were used to determine the performance of the inlet/fan system at the design point and to predict the performance and operability of the system over the flight profile. At the design point the core inlet had a recovery of 96 percent, and the fan operated near its peak efficiency and pressure ratio. A large hub radial distortion generated in the inlet was not eliminated by the fan and could pose a challenge for subsequent booster stages. The system operated stably at all points along the flight profile. Reduced stall margin was seen at low altitude and Mach number where flow separated on the interior lips of the cowl and bypass ducts. The coupled analysis gave consistent solutions at all points on the flight profile that would be difficult or impossible to predict by analysis of isolated components.

  6. Potential Effects of Leak-Before-Break on Light Water Reactor Design.

    DTIC Science & Technology

    1985-08-26

    Boiler and Pressure Vessel Code . In fact, section 3 of that code was created for nuclear applications. This... Boiler and Pressure Vessel Code . The only major change which leak-before-break would require in these analyses would be that all piping to be considered...XI of the ASME Boiler and Pressure Vessel Code , and is already required for all Class I piping systems in the plant. Class I systems are those

  7. Proceedings of the Workshop on software tools for distributed intelligent control systems

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

    Herget, C.J.

    1990-09-01

    The Workshop on Software Tools for Distributed Intelligent Control Systems was organized by Lawrence Livermore National Laboratory for the United States Army Headquarters Training and Doctrine Command and the Defense Advanced Research Projects Agency. The goals of the workshop were to the identify the current state of the art in tools which support control systems engineering design and implementation, identify research issues associated with writing software tools which would provide a design environment to assist engineers in multidisciplinary control design and implementation, formulate a potential investment strategy to resolve the research issues and develop public domain code which can formmore » the core of more powerful engineering design tools, and recommend test cases to focus the software development process and test associated performance metrics. Recognizing that the development of software tools for distributed intelligent control systems will require a multidisciplinary effort, experts in systems engineering, control systems engineering, and compute science were invited to participate in the workshop. In particular, experts who could address the following topics were selected: operating systems, engineering data representation and manipulation, emerging standards for manufacturing data, mathematical foundations, coupling of symbolic and numerical computation, user interface, system identification, system representation at different levels of abstraction, system specification, system design, verification and validation, automatic code generation, and integration of modular, reusable code.« less

  8. Athermalization of infrared dual field optical system based on wavefront coding

    NASA Astrophysics Data System (ADS)

    Jiang, Kai; Jiang, Bo; Liu, Kai; Yan, Peipei; Duan, Jing; Shan, Qiu-sha

    2017-02-01

    Wavefront coding is a technology which combination of the optical design and digital image processing. By inserting a phase mask closed to the pupil plane of the optical system the wavefront of the system is re-modulated. And the depth of focus is extended consequently. In reality the idea is same as the athermalization theory of infrared optical system. In this paper, an uncooled infrared dual field optical system with effective focal as 38mm/19mm, F number as 1.2 of both focal length, operating wavelength varying from 8μm to 12μm was designed. A cubic phase mask was used at the pupil plane to re-modulate the wavefront. Then the performance of the infrared system was simulated with CODEV as the environment temperature varying from -40° to 60°. MTF curve of the optical system with phase mask are compared with the outcome before using phase mask. The result show that wavefront coding technology can make the system not sensitive to thermal defocus, and then realize the athermal design of the infrared optical system.

  9. TFaNS Tone Fan Noise Design/Prediction System. Volume 1; System Description, CUP3D Technical Documentation and Manual for Code Developers

    NASA Technical Reports Server (NTRS)

    Topol, David A.

    1999-01-01

    TFaNS is the Tone Fan Noise Design/Prediction System developed by Pratt & Whitney under contract to NASA Lewis (presently NASA Glenn). The purpose of this system is to predict tone noise emanating from a fan stage including the effects of reflection and transmission by the rotor and stator and by the duct inlet and nozzle. These effects have been added to an existing annular duct/isolated stator noise prediction capability. TFaNS consists of: The codes that compute the acoustic properties (reflection and transmission coefficients) of the various elements and write them to files. Cup3D: Fan Noise Coupling Code that reads these files, solves the coupling problem, and outputs the desired noise predictions. AWAKEN: CFD/Measured Wake Postprocessor which reformats CFD wake predictions and/or measured wake data so it can be used by the system. This volume of the report provides technical background for TFaNS including the organization of the system and CUP3D technical documentation. This document also provides information for code developers who must write Acoustic Property Files in the CUP3D format. This report is divided into three volumes: Volume I: System Description, CUP3D Technical Documentation, and Manual for Code Developers; Volume II: User's Manual, TFaNS Vers. 1.4; Volume III: Evaluation of System Codes.

  10. Progress Toward Efficient Laminar Flow Analysis and Design

    NASA Technical Reports Server (NTRS)

    Campbell, Richard L.; Campbell, Matthew L.; Streit, Thomas

    2011-01-01

    A multi-fidelity system of computer codes for the analysis and design of vehicles having extensive areas of laminar flow is under development at the NASA Langley Research Center. The overall approach consists of the loose coupling of a flow solver, a transition prediction method and a design module using shell scripts, along with interface modules to prepare the input for each method. This approach allows the user to select the flow solver and transition prediction module, as well as run mode for each code, based on the fidelity most compatible with the problem and available resources. The design module can be any method that designs to a specified target pressure distribution. In addition to the interface modules, two new components have been developed: 1) an efficient, empirical transition prediction module (MATTC) that provides n-factor growth distributions without requiring boundary layer information; and 2) an automated target pressure generation code (ATPG) that develops a target pressure distribution that meets a variety of flow and geometry constraints. The ATPG code also includes empirical estimates of several drag components to allow the optimization of the target pressure distribution. The current system has been developed for the design of subsonic and transonic airfoils and wings, but may be extendable to other speed ranges and components. Several analysis and design examples are included to demonstrate the current capabilities of the system.

  11. Architecture and implementation considerations of a high-speed Viterbi decoder for a Reed-Muller subcode

    NASA Technical Reports Server (NTRS)

    Lin, Shu (Principal Investigator); Uehara, Gregory T.; Nakamura, Eric; Chu, Cecilia W. P.

    1996-01-01

    The (64, 40, 8) subcode of the third-order Reed-Muller (RM) code for high-speed satellite communications is proposed. The RM subcode can be used either alone or as an inner code of a concatenated coding system with the NASA standard (255, 233, 33) Reed-Solomon (RS) code as the outer code to achieve high performance (or low bit-error rate) with reduced decoding complexity. It can also be used as a component code in a multilevel bandwidth efficient coded modulation system to achieve reliable bandwidth efficient data transmission. The progress made toward achieving the goal of implementing a decoder system based upon this code is summarized. The development of the integrated circuit prototype sub-trellis IC, particularly focusing on the design methodology, is addressed.

  12. Development of the FHR advanced natural circulation analysis code and application to FHR safety analysis

    DOE PAGES

    Guo, Z.; Zweibaum, N.; Shao, M.; ...

    2016-04-19

    The University of California, Berkeley (UCB) is performing thermal hydraulics safety analysis to develop the technical basis for design and licensing of fluoride-salt-cooled, high-temperature reactors (FHRs). FHR designs investigated by UCB use natural circulation for emergency, passive decay heat removal when normal decay heat removal systems fail. The FHR advanced natural circulation analysis (FANCY) code has been developed for assessment of passive decay heat removal capability and safety analysis of these innovative system designs. The FANCY code uses a one-dimensional, semi-implicit scheme to solve for pressure-linked mass, momentum and energy conservation equations. Graph theory is used to automatically generate amore » staggered mesh for complicated pipe network systems. Heat structure models have been implemented for three types of boundary conditions (Dirichlet, Neumann and Robin boundary conditions). Heat structures can be composed of several layers of different materials, and are used for simulation of heat structure temperature distribution and heat transfer rate. Control models are used to simulate sequences of events or trips of safety systems. A proportional-integral controller is also used to automatically make thermal hydraulic systems reach desired steady state conditions. A point kinetics model is used to model reactor kinetics behavior with temperature reactivity feedback. The underlying large sparse linear systems in these models are efficiently solved by using direct and iterative solvers provided by the SuperLU code on high performance machines. Input interfaces are designed to increase the flexibility of simulation for complicated thermal hydraulic systems. In conclusion, this paper mainly focuses on the methodology used to develop the FANCY code, and safety analysis of the Mark 1 pebble-bed FHR under development at UCB is performed.« less

  13. Investigation of Near Shannon Limit Coding Schemes

    NASA Technical Reports Server (NTRS)

    Kwatra, S. C.; Kim, J.; Mo, Fan

    1999-01-01

    Turbo codes can deliver performance that is very close to the Shannon limit. This report investigates algorithms for convolutional turbo codes and block turbo codes. Both coding schemes can achieve performance near Shannon limit. The performance of the schemes is obtained using computer simulations. There are three sections in this report. First section is the introduction. The fundamental knowledge about coding, block coding and convolutional coding is discussed. In the second section, the basic concepts of convolutional turbo codes are introduced and the performance of turbo codes, especially high rate turbo codes, is provided from the simulation results. After introducing all the parameters that help turbo codes achieve such a good performance, it is concluded that output weight distribution should be the main consideration in designing turbo codes. Based on the output weight distribution, the performance bounds for turbo codes are given. Then, the relationships between the output weight distribution and the factors like generator polynomial, interleaver and puncturing pattern are examined. The criterion for the best selection of system components is provided. The puncturing pattern algorithm is discussed in detail. Different puncturing patterns are compared for each high rate. For most of the high rate codes, the puncturing pattern does not show any significant effect on the code performance if pseudo - random interleaver is used in the system. For some special rate codes with poor performance, an alternative puncturing algorithm is designed which restores their performance close to the Shannon limit. Finally, in section three, for iterative decoding of block codes, the method of building trellis for block codes, the structure of the iterative decoding system and the calculation of extrinsic values are discussed.

  14. Control Law Design in a Computational Aeroelasticity Environment

    NASA Technical Reports Server (NTRS)

    Newsom, Jerry R.; Robertshaw, Harry H.; Kapania, Rakesh K.

    2003-01-01

    A methodology for designing active control laws in a computational aeroelasticity environment is given. The methodology involves employing a systems identification technique to develop an explicit state-space model for control law design from the output of a computational aeroelasticity code. The particular computational aeroelasticity code employed in this paper solves the transonic small disturbance aerodynamic equation using a time-accurate, finite-difference scheme. Linear structural dynamics equations are integrated simultaneously with the computational fluid dynamics equations to determine the time responses of the structure. These structural responses are employed as the input to a modern systems identification technique that determines the Markov parameters of an "equivalent linear system". The Eigensystem Realization Algorithm is then employed to develop an explicit state-space model of the equivalent linear system. The Linear Quadratic Guassian control law design technique is employed to design a control law. The computational aeroelasticity code is modified to accept control laws and perform closed-loop simulations. Flutter control of a rectangular wing model is chosen to demonstrate the methodology. Various cases are used to illustrate the usefulness of the methodology as the nonlinearity of the aeroelastic system is increased through increased angle-of-attack changes.

  15. Development of an Object-Oriented Turbomachinery Analysis Code within the NPSS Framework

    NASA Technical Reports Server (NTRS)

    Jones, Scott M.

    2014-01-01

    During the preliminary or conceptual design phase of an aircraft engine, the turbomachinery designer has a need to estimate the effects of a large number of design parameters such as flow size, stage count, blade count, radial position, etc. on the weight and efficiency of a turbomachine. Computer codes are invariably used to perform this task however, such codes are often very old, written in outdated languages with arcane input files, and rarely adaptable to new architectures or unconventional layouts. Given the need to perform these kinds of preliminary design trades, a modern 2-D turbomachinery design and analysis code has been written using the Numerical Propulsion System Simulation (NPSS) framework. This paper discusses the development of the governing equations and the structure of the primary objects used in OTAC.

  16. TFaNS Tone Fan Noise Design/Prediction System. Volume 2; User's Manual; 1.4

    NASA Technical Reports Server (NTRS)

    Topol, David A.; Eversman, Walter

    1999-01-01

    TFaNS is the Tone Fan Noise Design/Prediction System developed by Pratt & Whitney under contract to NASA Lewis (presently NASA Glenn). The purpose of this system is to predict tone noise emanating from a fan stage including the effects of reflection and transmission by the rotor and stator and by the duct inlet and nozzle. These effects have been added to an existing annular duct/isolated stator noise prediction capability. TFaNS consists of: the codes that compute the acoustic properties (reflection and transmission coefficients) of the various elements and write them to files. CUP3D: Fan Noise Coupling Code that reads these files, solves the coupling problem, and outputs the desired noise predictions. AWAKEN: CFD/Measured Wake Postprocessor which reformats CFD wake predictions and/or measured wake data so it can be used by the system. This volume of the report provides information on code input and file structure essential for potential users of TFANS. This report is divided into three volumes: Volume 1. System Description, CUP3D Technical Documentation, and Manual for Code Developers; Volume 2. User's Manual, TFANS Vers. 1.4; Volume 3. Evaluation of System Codes.

  17. The role of CFD in the design process

    NASA Astrophysics Data System (ADS)

    Jennions, Ian K.

    1994-05-01

    Over the last decade the role played by CFD codes in turbomachinery design has changed remarkably. While convergence/stability or even the existence of unique solutions was discussed fervently ten years ago, CFD codes now form a valuable part of an overall integrated design system and have caused us to re-think much of what we do. The geometric and physical complexities addressed have also evolved, as have the number of software houses competing with in-house developers to provide solutions to daily design problems. This paper reviews how GE Aircraft Engines (GEAE) uses CFD in the turbomachinery design process and examines many of the issues faced in successful code implementation.

  18. Design and Experimental Results for the S414 Airfoil

    DTIC Science & Technology

    2010-08-01

    EXECUTION The Eppler Airfoil Design and Analysis Code (refs. 15 and 16), a subcritical, single- element code, was used to design the initial fore- and...1965. 14. Maughmer, Mark D.: Trailing Edge Conditions as a Factor in Airfoil Design. Ph.D. Dis- sertation, Univ. of Illinois, 1983.14 15. Eppler ...Richard: Airfoil Design and Data. Springer-Verlag (Berlin), 1990. 16. Eppler , Richard: Airfoil Program System “PROFIL07.” User’s Guide. Richard

  19. Shuttle Global Positioning System (GPS) system design study

    NASA Technical Reports Server (NTRS)

    Nilsen, P. W.

    1979-01-01

    The various integration problems in the Shuttle GPS system were investigated. The analysis of the Shuttle GPS link was studied. A preamplifier was designed since the Shuttle GPS antennas must be located remotely from the receiver. Several GPS receiver architecture trade-offs were discussed. The Shuttle RF harmonics and intermode that fall within the GPS receiver bandwidth were analyzed. The GPS PN code acquisition was examined. Since the receiver clock strongly affects both GPS carrier and code acquisition performance, a clock model was developed.

  20. Efficient Signal, Code, and Receiver Designs for MIMO Communication Systems

    DTIC Science & Technology

    2003-06-01

    167 5-31 Concatenation of a tilted-QAM inner code with an LDPC outer code with a two component iterative soft-decision decoder. . . . . . . . . 168 5...for AWGN channels has long been studied. There are well-known soft-decision codes like the turbo codes and LDPC codes that can approach capacity to...bits) low density parity check ( LDPC ) code 1. 2. The coded bits are randomly interleaved so that bits nearby go through different sub-channels, and are

  1. System statistical reliability model and analysis

    NASA Technical Reports Server (NTRS)

    Lekach, V. S.; Rood, H.

    1973-01-01

    A digital computer code was developed to simulate the time-dependent behavior of the 5-kwe reactor thermoelectric system. The code was used to determine lifetime sensitivity coefficients for a number of system design parameters, such as thermoelectric module efficiency and degradation rate, radiator absorptivity and emissivity, fuel element barrier defect constant, beginning-of-life reactivity, etc. A probability distribution (mean and standard deviation) was estimated for each of these design parameters. Then, error analysis was used to obtain a probability distribution for the system lifetime (mean = 7.7 years, standard deviation = 1.1 years). From this, the probability that the system will achieve the design goal of 5 years lifetime is 0.993. This value represents an estimate of the degradation reliability of the system.

  2. The application of coded excitation technology in medical ultrasonic Doppler imaging

    NASA Astrophysics Data System (ADS)

    Li, Weifeng; Chen, Xiaodong; Bao, Jing; Yu, Daoyin

    2008-03-01

    Medical ultrasonic Doppler imaging is one of the most important domains of modern medical imaging technology. The application of coded excitation technology in medical ultrasonic Doppler imaging system has the potential of higher SNR and deeper penetration depth than conventional pulse-echo imaging system, it also improves the image quality, and enhances the sensitivity of feeble signal, furthermore, proper coded excitation is beneficial to received spectrum of Doppler signal. Firstly, this paper analyzes the application of coded excitation technology in medical ultrasonic Doppler imaging system abstractly, showing the advantage and bright future of coded excitation technology, then introduces the principle and the theory of coded excitation. Secondly, we compare some coded serials (including Chirp and fake Chirp signal, Barker codes, Golay's complementary serial, M-sequence, etc). Considering Mainlobe Width, Range Sidelobe Level, Signal-to-Noise Ratio and sensitivity of Doppler signal, we choose Barker codes as coded serial. At last, we design the coded excitation circuit. The result in B-mode imaging and Doppler flow measurement coincided with our expectation, which incarnated the advantage of application of coded excitation technology in Digital Medical Ultrasonic Doppler Endoscope Imaging System.

  3. National Combustion Code: A Multidisciplinary Combustor Design System

    NASA Technical Reports Server (NTRS)

    Stubbs, Robert M.; Liu, Nan-Suey

    1997-01-01

    The Internal Fluid Mechanics Division conducts both basic research and technology, and system technology research for aerospace propulsion systems components. The research within the division, which is both computational and experimental, is aimed at improving fundamental understanding of flow physics in inlets, ducts, nozzles, turbomachinery, and combustors. This article and the following three articles highlight some of the work accomplished in 1996. A multidisciplinary combustor design system is critical for optimizing the combustor design process. Such a system should include sophisticated computer-aided design (CAD) tools for geometry creation, advanced mesh generators for creating solid model representations, a common framework for fluid flow and structural analyses, modern postprocessing tools, and parallel processing. The goal of the present effort is to develop some of the enabling technologies and to demonstrate their overall performance in an integrated system called the National Combustion Code.

  4. Description of the L1C signal

    USGS Publications Warehouse

    Betz, J.W.; Blanco, M.A.; Cahn, C.R.; Dafesh, P.A.; Hegarty, C.J.; Hudnut, K.W.; Kasemsri, V.; Keegan, R.; Kovach, K.; Lenahan, L.S.; Ma, H.H.; Rushanan, J.J.; Sklar, D.; Stansell, T.A.; Wang, C.C.; Yi, S.K.

    2006-01-01

    Detailed design of the modernized LI civil signal (L1C) signal has been completed, and the resulting draft Interface Specification IS-GPS-800 was released in Spring 2006. The novel characteristics of the optimized L1C signal design provide advanced capabilities while offering to receiver designers considerable flexibility in how to use these capabilities. L1C provides a number of advanced features, including: 75% of power in a pilot component for enhanced signal tracking, advanced Weilbased spreading codes, an overlay code on the pilot that provides data message synchronization, support for improved reading of clock and ephemeris by combining message symbols across messages, advanced forward error control coding, and data symbol interleaving to combat fading. The resulting design offers receiver designers the opportunity to obtain unmatched performance in many ways. This paper describes the design of L1C. A summary of LIC's background and history is provided. The signal description then proceeds with the overall signal structure consisting of a pilot component and a carrier component. The new L1C spreading code family is described, along with the logic used for generating these spreading codes. Overlay codes on the pilot channel are also described, as is the logic used for generating the overlay codes. Spreading modulation characteristics are summarized. The data message structure is also presented, showing the format for providing time, ephemeris, and system data to users, along with features that enable receivers to perform code combining. Encoding of rapidly changing time bits is described, as are the Low Density Parity Check codes used for forward error control of slowly changing time bits, clock, ephemeris, and system data. The structure of the interleaver is also presented. A summary of L 1C's unique features and their benefits is provided, along with a discussion of the plan for L1C implementation.

  5. ARES: automated response function code. Users manual. [HPGAM and LSQVM

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

    Maung, T.; Reynolds, G.M.

    This ARES user's manual provides detailed instructions for a general understanding of the Automated Response Function Code and gives step by step instructions for using the complete code package on a HP-1000 system. This code is designed to calculate response functions of NaI gamma-ray detectors, with cylindrical or rectangular geometries.

  6. An all-digital receiver for satellite audio broadcasting signals using trellis coded quasi-orthogonal code-division multiplexing

    NASA Astrophysics Data System (ADS)

    Braun, Walter; Eglin, Peter; Abello, Ricard

    1993-02-01

    Spread Spectrum Code Division Multiplex is an attractive scheme for the transmission of multiple signals over a satellite transponder. By using orthogonal or quasi-orthogonal spreading codes the interference between the users can be virtually eliminated. However, the acquisition and tracking of the spreading code phase can not take advantage of the code orthogonality since sequential acquisition and Delay-Locked loop tracking depend on correlation with code phases other than the optimal despreading phase. Hence, synchronization is a critical issue in such a system. A demonstration hardware for the verification of the orthogonal CDM synchronization and data transmission concept is being designed and implemented. The system concept, the synchronization scheme, and the implementation are described. The performance of the system is discussed based on computer simulations.

  7. Coupled dynamics analysis of wind energy systems

    NASA Technical Reports Server (NTRS)

    Hoffman, J. A.

    1977-01-01

    A qualitative description of all key elements of a complete wind energy system computer analysis code is presented. The analysis system addresses the coupled dynamics characteristics of wind energy systems, including the interactions of the rotor, tower, nacelle, power train, control system, and electrical network. The coupled dynamics are analyzed in both the frequency and time domain to provide the basic motions and loads data required for design, performance verification and operations analysis activities. Elements of the coupled analysis code were used to design and analyze candidate rotor articulation concepts. Fundamental results and conclusions derived from these studies are presented.

  8. Computational electronics and electromagnetics

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

    Shang, C. C.

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

  9. CFC (Comment-First-Coding)--A Simple yet Effective Method for Teaching Programming to Information Systems Students

    ERIC Educational Resources Information Center

    Sengupta, Arijit

    2009-01-01

    Programming courses have always been a difficult part of an Information Systems curriculum. While we do not train Information Systems students to be developers, understanding how to build a system always gives students an added perspective to improve their system design and analysis skills. This teaching tip presents CFC (Comment-First-Coding)--a…

  10. Evaluation of Recent Upgrades to the NESS (Nuclear Engine System Simulation) Code

    NASA Technical Reports Server (NTRS)

    Fittje, James E.; Schnitzler, Bruce G.

    2008-01-01

    The Nuclear Thermal Rocket (NTR) concept is being evaluated as a potential propulsion technology for exploratory expeditions to the moon, Mars, and beyond. The need for exceptional propulsion system performance in these missions has been documented in numerous studies, and was the primary focus of a considerable effort undertaken during the Rover/NERVA program from 1955 to 1973. The NASA Glenn Research Center is leveraging this past NTR investment in their vehicle concepts and mission analysis studies with the aid of the Nuclear Engine System Simulation (NESS) code. This paper presents the additional capabilities and upgrades made to this code in order to perform higher fidelity NTR propulsion system analysis and design, and a comparison of its results to the Small Nuclear Rocket Engine (SNRE) design.

  11. Software Considerations for Subscale Flight Testing of Experimental Control Laws

    NASA Technical Reports Server (NTRS)

    Murch, Austin M.; Cox, David E.; Cunningham, Kevin

    2009-01-01

    The NASA AirSTAR system has been designed to address the challenges associated with safe and efficient subscale flight testing of research control laws in adverse flight conditions. In this paper, software elements of this system are described, with an emphasis on components which allow for rapid prototyping and deployment of aircraft control laws. Through model-based design and automatic coding a common code-base is used for desktop analysis, piloted simulation and real-time flight control. The flight control system provides the ability to rapidly integrate and test multiple research control laws and to emulate component or sensor failures. Integrated integrity monitoring systems provide aircraft structural load protection, isolate the system from control algorithm failures, and monitor the health of telemetry streams. Finally, issues associated with software configuration management and code modularity are briefly discussed.

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

    Janjusic, Tommy; Kartsaklis, Christos

    Memory scalability is an enduring problem and bottleneck that plagues many parallel codes. Parallel codes designed for High Performance Systems are typically designed over the span of several, and in some instances 10+, years. As a result, optimization practices which were appropriate for earlier systems may no longer be valid and thus require careful optimization consideration. Specifically, parallel codes whose memory footprint is a function of their scalability must be carefully considered for future exa-scale systems. In this paper we present a methodology and tool to study the memory scalability of parallel codes. Using our methodology we evaluate an applicationmore » s memory footprint as a function of scalability, which we coined memory efficiency, and describe our results. In particular, using our in-house tools we can pinpoint the specific application components which contribute to the application s overall memory foot-print (application data- structures, libraries, etc.).« less

  13. Coded spread spectrum digital transmission system design study

    NASA Technical Reports Server (NTRS)

    Heller, J. A.; Odenwalder, J. P.; Viterbi, A. J.

    1974-01-01

    Results are presented of a comprehensive study of the performance of Viterbi-decoded convolutional codes in the presence of nonideal carrier tracking and bit synchronization. A constraint length 7, rate 1/3 convolutional code and parameters suitable for the space shuttle coded communications links are used. Mathematical models are developed and theoretical and simulation results are obtained to determine the tracking and acquisition performance of the system. Pseudorandom sequence spread spectrum techniques are also considered to minimize potential degradation caused by multipath.

  14. Multidisciplinary Aerospace Systems Optimization: Computational AeroSciences (CAS) Project

    NASA Technical Reports Server (NTRS)

    Kodiyalam, S.; Sobieski, Jaroslaw S. (Technical Monitor)

    2001-01-01

    The report describes a method for performing optimization of a system whose analysis is so expensive that it is impractical to let the optimization code invoke it directly because excessive computational cost and elapsed time might result. In such situation it is imperative to have user control the number of times the analysis is invoked. The reported method achieves that by two techniques in the Design of Experiment category: a uniform dispersal of the trial design points over a n-dimensional hypersphere and a response surface fitting, and the technique of krigging. Analyses of all the trial designs whose number may be set by the user are performed before activation of the optimization code and the results are stored as a data base. That code is then executed and referred to the above data base. Two applications, one of the airborne laser system, and one of an aircraft optimization illustrate the method application.

  15. A coded tracking telemetry system

    USGS Publications Warehouse

    Howey, P.W.; Seegar, W.S.; Fuller, M.R.; Titus, K.; Amlaner, Charles J.

    1989-01-01

    We describe the general characteristics of an automated radio telemetry system designed to operate for prolonged periods on a single frequency. Each transmitter sends a unique coded signal to a receiving system that encodes and records only the appropriater, pre-programmed codes. A record of the time of each reception is stored on diskettes in a micro-computer. This system enables continuous monitoring of infrequent signals (e.g. one per minute or one per hour), thus extending operation life or allowing size reduction of the transmitter, compared to conventional wildlife telemetry. Furthermore, when using unique codes transmitted on a single frequency, biologists can monitor many individuals without exceeding the radio frequency allocations for wildlife.

  16. Burst mode PCS of EPON

    NASA Astrophysics Data System (ADS)

    Du, Xiao

    2005-02-01

    Normal GIGA ETHERNET continuously transmits or receives 8B/10B codes including data codes, idle codes or configuration information. In ETHERNET network, one computer links one port of switch through CAT5 and that is OK. But for EPON, it is different. All ONUs share one fiber in upstream, if we inherit the GIGA ETHERNET PHY, then collision will occur. All ONUs always transmit 8B/10B codes, and the optical signal will overlay. The OLT will receive the fault information. So we need a novel EPON PHY instead of ETHERNET PHY. But its major function is compatible with ETHERNET"s. In this article, first, the function of PCS sub layer is discussed and a novel PCS module is given that can be used in not only EPON system but also in GIGA ETHERNET system. The design of PCS is based on 1000BASE-X PCS technology. And the function of 1000BASE-X PCS should be accomplished first. Next we modify the design in order to meet the requirements of EPON system. In the new design, the auto negotiation and synchronization is the same to the 1000 BASE-X technology.

  17. SCALE: A modular code system for performing standardized computer analyses for licensing evaluation. Functional modules F1--F8 -- Volume 2, Part 1, Revision 4

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

    Greene, N.M.; Petrie, L.M.; Westfall, R.M.

    SCALE--a modular code system for Standardized Computer Analyses Licensing Evaluation--has been developed by Oak Ridge National Laboratory at the request of the US Nuclear Regulatory Commission. The SCALE system utilizes well-established computer codes and methods within standard analysis sequences that (1) allow an input format designed for the occasional user and/or novice, (2) automate the data processing and coupling between modules, and (3) provide accurate and reliable results. System development has been directed at problem-dependent cross-section processing and analysis of criticality safety, shielding, heat transfer, and depletion/decay problems. Since the initial release of SCALE in 1980, the code system hasmore » been heavily used for evaluation of nuclear fuel facility and package designs. This revision documents Version 4.2 of the system. The manual is divided into three volumes: Volume 1--for the control module documentation; Volume 2--for functional module documentation; and Volume 3--for documentation of the data libraries and subroutine libraries.« less

  18. Side information in coded aperture compressive spectral imaging

    NASA Astrophysics Data System (ADS)

    Galvis, Laura; Arguello, Henry; Lau, Daniel; Arce, Gonzalo R.

    2017-02-01

    Coded aperture compressive spectral imagers sense a three-dimensional cube by using two-dimensional projections of the coded and spectrally dispersed source. These imagers systems often rely on FPA detectors, SLMs, micromirror devices (DMDs), and dispersive elements. The use of the DMDs to implement the coded apertures facilitates the capture of multiple projections, each admitting a different coded aperture pattern. The DMD allows not only to collect the sufficient number of measurements for spectrally rich scenes or very detailed spatial scenes but to design the spatial structure of the coded apertures to maximize the information content on the compressive measurements. Although sparsity is the only signal characteristic usually assumed for reconstruction in compressing sensing, other forms of prior information such as side information have been included as a way to improve the quality of the reconstructions. This paper presents the coded aperture design in a compressive spectral imager with side information in the form of RGB images of the scene. The use of RGB images as side information of the compressive sensing architecture has two main advantages: the RGB is not only used to improve the reconstruction quality but to optimally design the coded apertures for the sensing process. The coded aperture design is based on the RGB scene and thus the coded aperture structure exploits key features such as scene edges. Real reconstructions of noisy compressed measurements demonstrate the benefit of the designed coded apertures in addition to the improvement in the reconstruction quality obtained by the use of side information.

  19. Channel coding for underwater acoustic single-carrier CDMA communication system

    NASA Astrophysics Data System (ADS)

    Liu, Lanjun; Zhang, Yonglei; Zhang, Pengcheng; Zhou, Lin; Niu, Jiong

    2017-01-01

    CDMA is an effective multiple access protocol for underwater acoustic networks, and channel coding can effectively reduce the bit error rate (BER) of the underwater acoustic communication system. For the requirements of underwater acoustic mobile networks based on CDMA, an underwater acoustic single-carrier CDMA communication system (UWA/SCCDMA) based on the direct-sequence spread spectrum is proposed, and its channel coding scheme is studied based on convolution, RA, Turbo and LDPC coding respectively. The implementation steps of the Viterbi algorithm of convolutional coding, BP and minimum sum algorithms of RA coding, Log-MAP and SOVA algorithms of Turbo coding, and sum-product algorithm of LDPC coding are given. An UWA/SCCDMA simulation system based on Matlab is designed. Simulation results show that the UWA/SCCDMA based on RA, Turbo and LDPC coding have good performance such that the communication BER is all less than 10-6 in the underwater acoustic channel with low signal to noise ratio (SNR) from -12 dB to -10dB, which is about 2 orders of magnitude lower than that of the convolutional coding. The system based on Turbo coding with Log-MAP algorithm has the best performance.

  20. Preliminary LOCA analysis of the westinghouse small modular reactor using the WCOBRA/TRAC-TF2 thermal-hydraulics code

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

    Liao, J.; Kucukboyaci, V. N.; Nguyen, L.

    2012-07-01

    The Westinghouse Small Modular Reactor (SMR) is an 800 MWt (> 225 MWe) integral pressurized water reactor (iPWR) with all primary components, including the steam generator and the pressurizer located inside the reactor vessel. The reactor core is based on a partial-height 17x17 fuel assembly design used in the AP1000{sup R} reactor core. The Westinghouse SMR utilizes passive safety systems and proven components from the AP1000 plant design with a compact containment that houses the integral reactor vessel and the passive safety systems. A preliminary loss of coolant accident (LOCA) analysis of the Westinghouse SMR has been performed using themore » WCOBRA/TRAC-TF2 code, simulating a transient caused by a double ended guillotine (DEG) break in the direct vessel injection (DVI) line. WCOBRA/TRAC-TF2 is a new generation Westinghouse LOCA thermal-hydraulics code evolving from the US NRC licensed WCOBRA/TRAC code. It is designed to simulate PWR LOCA events from the smallest break size to the largest break size (DEG cold leg). A significant number of fluid dynamics models and heat transfer models were developed or improved in WCOBRA/TRAC-TF2. A large number of separate effects and integral effects tests were performed for a rigorous code assessment and validation. WCOBRA/TRAC-TF2 was introduced into the Westinghouse SMR design phase to assist a quick and robust passive cooling system design and to identify thermal-hydraulic phenomena for the development of the SMR Phenomena Identification Ranking Table (PIRT). The LOCA analysis of the Westinghouse SMR demonstrates that the DEG DVI break LOCA is mitigated by the injection and venting from the Westinghouse SMR passive safety systems without core heat up, achieving long term core cooling. (authors)« less

  1. Analysis of airborne antenna systems using geometrical theory of diffraction and moment method computer codes

    NASA Technical Reports Server (NTRS)

    Hartenstein, Richard G., Jr.

    1985-01-01

    Computer codes have been developed to analyze antennas on aircraft and in the presence of scatterers. The purpose of this study is to use these codes to develop accurate computer models of various aircraft and antenna systems. The antenna systems analyzed are a P-3B L-Band antenna, an A-7E UHF relay pod antenna, and traffic advisory antenna system installed on a Bell Long Ranger helicopter. Computer results are compared to measured ones with good agreement. These codes can be used in the design stage of an antenna system to determine the optimum antenna location and save valuable time and costly flight hours.

  2. TFaNS-Tone Fan Noise Design/Prediction System: Users' Manual TFaNS Version 1.5

    NASA Technical Reports Server (NTRS)

    Topol, David A.; Huff, Dennis L. (Technical Monitor)

    2003-01-01

    TFaNS is the Tone Fan Noise Design/Prediction System developed by Pratt & Whitney under contract to NASA Glenn. The purpose of this system is to predict tone noise emanating from a fan stage including the effects of reflection and transmission by the rotor and stator and by the duct inlet and nozzle. The first version of this design system was developed under a previous NASA contract. Several improvements have been made to TFaNS. This users' manual shows how to run this new system. TFaNS consists of the codes that compute the acoustic properties (reflection and transmission coefficients) of the various elements and writes them to files, CUP3D Fan Noise Coupling Code that reads these files, solves the coupling problem, and outputs the desired noise predictions, and AWAKEN CFD/Measured Wake Postprocessor which reformats CFD wake predictions and/or measured wake data so they can be used by the system. This report provides information on code input and file structure essential for potential users of TFaNS.

  3. Computerized systems analysis and optimization of aircraft engine performance, weight, and life cycle costs

    NASA Technical Reports Server (NTRS)

    Fishbach, L. H.

    1979-01-01

    The computational techniques utilized to determine the optimum propulsion systems for future aircraft applications and to identify system tradeoffs and technology requirements are described. The characteristics and use of the following computer codes are discussed: (1) NNEP - a very general cycle analysis code that can assemble an arbitrary matrix fans, turbines, ducts, shafts, etc., into a complete gas turbine engine and compute on- and off-design thermodynamic performance; (2) WATE - a preliminary design procedure for calculating engine weight using the component characteristics determined by NNEP; (3) POD DRG - a table look-up program to calculate wave and friction drag of nacelles; (4) LIFCYC - a computer code developed to calculate life cycle costs of engines based on the output from WATE; and (5) INSTAL - a computer code developed to calculate installation effects, inlet performance and inlet weight. Examples are given to illustrate how these computer techniques can be applied to analyze and optimize propulsion system fuel consumption, weight, and cost for representative types of aircraft and missions.

  4. Optimized nonorthogonal transforms for image compression.

    PubMed

    Guleryuz, O G; Orchard, M T

    1997-01-01

    The transform coding of images is analyzed from a common standpoint in order to generate a framework for the design of optimal transforms. It is argued that all transform coders are alike in the way they manipulate the data structure formed by transform coefficients. A general energy compaction measure is proposed to generate optimized transforms with desirable characteristics particularly suited to the simple transform coding operation of scalar quantization and entropy coding. It is shown that the optimal linear decoder (inverse transform) must be an optimal linear estimator, independent of the structure of the transform generating the coefficients. A formulation that sequentially optimizes the transforms is presented, and design equations and algorithms for its computation provided. The properties of the resulting transform systems are investigated. In particular, it is shown that the resulting basis are nonorthogonal and complete, producing energy compaction optimized, decorrelated transform coefficients. Quantization issues related to nonorthogonal expansion coefficients are addressed with a simple, efficient algorithm. Two implementations are discussed, and image coding examples are given. It is shown that the proposed design framework results in systems with superior energy compaction properties and excellent coding results.

  5. Incorporation of Dynamic SSI Effects in the Design Response Spectra

    NASA Astrophysics Data System (ADS)

    Manjula, N. K.; Pillai, T. M. Madhavan; Nagarajan, Praveen; Reshma, K. K.

    2018-05-01

    Many studies in the past on dynamic soil-structure interactions have revealed the detrimental and advantageous effects of soil flexibility. Based on such studies, the design response spectra of international seismic codes are being improved worldwide. The improvements required for the short period range of the design response spectra in the Indian seismic code (IS 1893:2002) are presented in this paper. As the recent code revisions has not incorporated the short period amplifications, proposals given in this paper are equally applicable for the latest code also (IS 1893:2016). Analyses of single degree of freedom systems are performed to predict the required improvements. The proposed modifications to the constant acceleration portion of the spectra are evaluated with respect to the current design spectra in Eurocode 8.

  6. No Sweat.

    ERIC Educational Resources Information Center

    Strickland, Gary

    2001-01-01

    Explains how changes in school design in the last 10 years have caused heating, ventilation, and cooling system (HVAC) designers to reexamine their choice of classroom unit ventilators (UV). The influence of indoor lighting systems, insulation, indoor air quality, energy code compliance, and HVAC system design on UV decision making are also…

  7. AspectAssay: A Technique for Expanding the Pool of Available Aspect Mining Test Data Using Concern Seeding

    ERIC Educational Resources Information Center

    Moore, David G., Jr.

    2013-01-01

    Aspect-oriented software design (AOSD) enables better and more complete separation of concerns in software-intensive systems. By extracting aspect code and relegating crosscutting functionality to aspects, software engineers can improve the maintainability of their code by reducing code tangling and coupling of code concerns. Further, the number…

  8. The general theory of convolutional codes

    NASA Technical Reports Server (NTRS)

    Mceliece, R. J.; Stanley, R. P.

    1993-01-01

    This article presents a self-contained introduction to the algebraic theory of convolutional codes. This introduction is partly a tutorial, but at the same time contains a number of new results which will prove useful for designers of advanced telecommunication systems. Among the new concepts introduced here are the Hilbert series for a convolutional code and the class of compact codes.

  9. Design and implementation of online automatic judging system

    NASA Astrophysics Data System (ADS)

    Liang, Haohui; Chen, Chaojie; Zhong, Xiuyu; Chen, Yuefeng

    2017-06-01

    For lower efficiency and poorer reliability in programming training and competition by currently artificial judgment, design an Online Automatic Judging (referred to as OAJ) System. The OAJ system including the sandbox judging side and Web side, realizes functions of automatically compiling and running the tested codes, and generating evaluation scores and corresponding reports. To prevent malicious codes from damaging system, the OAJ system utilizes sandbox, ensuring the safety of the system. The OAJ system uses thread pools to achieve parallel test, and adopt database optimization mechanism, such as horizontal split table, to improve the system performance and resources utilization rate. The test results show that the system has high performance, high reliability, high stability and excellent extensibility.

  10. A Rocket Engine Design Expert System

    NASA Technical Reports Server (NTRS)

    Davidian, Kenneth J.

    1989-01-01

    The overall structure and capabilities of an expert system designed to evaluate rocket engine performance are described. The expert system incorporates a JANNAF standard reference computer code to determine rocket engine performance and a state of the art finite element computer code to calculate the interactions between propellant injection, energy release in the combustion chamber, and regenerative cooling heat transfer. Rule-of-thumb heuristics were incorporated for the H2-O2 coaxial injector design, including a minimum gap size constraint on the total number of injector elements. One dimensional equilibrium chemistry was used in the energy release analysis of the combustion chamber. A 3-D conduction and/or 1-D advection analysis is used to predict heat transfer and coolant channel wall temperature distributions, in addition to coolant temperature and pressure drop. Inputting values to describe the geometry and state properties of the entire system is done directly from the computer keyboard. Graphical display of all output results from the computer code analyses is facilitated by menu selection of up to five dependent variables per plot.

  11. A rocket engine design expert system

    NASA Technical Reports Server (NTRS)

    Davidian, Kenneth J.

    1989-01-01

    The overall structure and capabilities of an expert system designed to evaluate rocket engine performance are described. The expert system incorporates a JANNAF standard reference computer code to determine rocket engine performance and a state-of-the-art finite element computer code to calculate the interactions between propellant injection, energy release in the combustion chamber, and regenerative cooling heat transfer. Rule-of-thumb heuristics were incorporated for the hydrogen-oxygen coaxial injector design, including a minimum gap size constraint on the total number of injector elements. One-dimensional equilibrium chemistry was employed in the energy release analysis of the combustion chamber and three-dimensional finite-difference analysis of the regenerative cooling channels was used to calculate the pressure drop along the channels and the coolant temperature as it exits the coolant circuit. Inputting values to describe the geometry and state properties of the entire system is done directly from the computer keyboard. Graphical display of all output results from the computer code analyses is facilitated by menu selection of up to five dependent variables per plot.

  12. Development of an extensible dual-core wireless sensing node for cyber-physical systems

    NASA Astrophysics Data System (ADS)

    Kane, Michael; Zhu, Dapeng; Hirose, Mitsuhito; Dong, Xinjun; Winter, Benjamin; Häckell, Mortiz; Lynch, Jerome P.; Wang, Yang; Swartz, A.

    2014-04-01

    The introduction of wireless telemetry into the design of monitoring and control systems has been shown to reduce system costs while simplifying installations. To date, wireless nodes proposed for sensing and actuation in cyberphysical systems have been designed using microcontrollers with one computational pipeline (i.e., single-core microcontrollers). While concurrent code execution can be implemented on single-core microcontrollers, concurrency is emulated by splitting the pipeline's resources to support multiple threads of code execution. For many applications, this approach to multi-threading is acceptable in terms of speed and function. However, some applications such as feedback controls demand deterministic timing of code execution and maximum computational throughput. For these applications, the adoption of multi-core processor architectures represents one effective solution. Multi-core microcontrollers have multiple computational pipelines that can execute embedded code in parallel and can be interrupted independent of one another. In this study, a new wireless platform named Martlet is introduced with a dual-core microcontroller adopted in its design. The dual-core microcontroller design allows Martlet to dedicate one core to standard wireless sensor operations while the other core is reserved for embedded data processing and real-time feedback control law execution. Another distinct feature of Martlet is a standardized hardware interface that allows specialized daughter boards (termed wing boards) to be interfaced to the Martlet baseboard. This extensibility opens opportunity to encapsulate specialized sensing and actuation functions in a wing board without altering the design of Martlet. In addition to describing the design of Martlet, a few example wings are detailed, along with experiments showing the Martlet's ability to monitor and control physical systems such as wind turbines and buildings.

  13. Design Aspects of the Rayleigh Convection Code

    NASA Astrophysics Data System (ADS)

    Featherstone, N. A.

    2017-12-01

    Understanding the long-term generation of planetary or stellar magnetic field requires complementary knowledge of the large-scale fluid dynamics pervading large fractions of the object's interior. Such large-scale motions are sensitive to the system's geometry which, in planets and stars, is spherical to a good approximation. As a result, computational models designed to study such systems often solve the MHD equations in spherical geometry, frequently employing a spectral approach involving spherical harmonics. We present computational and user-interface design aspects of one such modeling tool, the Rayleigh convection code, which is suitable for deployment on desktop and petascale-hpc architectures alike. In this poster, we will present an overview of this code's parallel design and its built-in diagnostics-output package. Rayleigh has been developed with NSF support through the Computational Infrastructure for Geodynamics and is expected to be released as open-source software in winter 2017/2018.

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

    Sesigur, Haluk; Cili, Feridun

    Seismic isolation is an effective design strategy to mitigate the seismic hazard wherein the structure and its contents are protected from the damaging effects of an earthquake. This paper presents the Hangar Project in Sabiha Goekcen Airport which is located in Istanbul, Turkey. Seismic isolation system where the isolation layer arranged at the top of the columns is selected. The seismic hazard analysis, superstructure design, isolator design and testing were based on the Uniform Building Code (1997) and met all requirements of the Turkish Earthquake Code (2007). The substructure which has the steel vertical trusses on facades and RC Hmore » shaped columns in the middle axis of the building was designed with an R factor limited to 2.0 in accordance with Turkish Earthquake Code. In order to verify the effectiveness of the isolation system, nonlinear static and dynamic analyses are performed. The analysis revealed that isolated building has lower base shear (approximately 1/4) against the non-isolated structure.« less

  15. Optical network security using unipolar Walsh code

    NASA Astrophysics Data System (ADS)

    Sikder, Somali; Sarkar, Madhumita; Ghosh, Shila

    2018-04-01

    Optical code-division multiple-access (OCDMA) is considered as a good technique to provide optical layer security. Many research works have been published to enhance optical network security by using optical signal processing. The paper, demonstrates the design of the AWG (arrayed waveguide grating) router-based optical network for spectral-amplitude-coding (SAC) OCDMA networks with Walsh Code to design a reconfigurable network codec by changing signature codes to against eavesdropping. In this paper we proposed a code reconfiguration scheme to improve the network access confidentiality changing the signature codes by cyclic rotations, for OCDMA system. Each of the OCDMA network users is assigned a unique signature code to transmit the information and at the receiving end each receiver correlates its own signature pattern a(n) with the receiving pattern s(n). The signal arriving at proper destination leads to s(n)=a(n).

  16. 77 FR 74351 - Fees for Reviews of the Rule Enforcement Programs of Designated Contract Markets and Registered...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-14

    ... Budget Program Activity Codes (BPAC) system, formerly the Management Accounting Structure Codes (MASC... charges fees to designated contract markets and registered futures associations to recover the costs... notice is based upon an average of actual program costs incurred during FY 2009, 2010, and 2011. DATES...

  17. Radiation in Space and Its Control of Equilibrium Temperatures in the Solar System

    NASA Technical Reports Server (NTRS)

    Juhasz, Albert J.

    2004-01-01

    The problem of determining equilibrium temperatures for reradiating surfaces in space vacuum was analyzed and the resulting mathematical relationships were incorporated in a code to determine space sink temperatures in the solar system. A brief treatment of planetary atmospheres is also included. Temperature values obtained with the code are in good agreement with available spacecraft telemetry and meteorological measurements for Venus and Earth. The code has been used in the design of space power system radiators for future interplanetary missions.

  18. The FORTRAN static source code analyzer program (SAP) system description

    NASA Technical Reports Server (NTRS)

    Decker, W.; Taylor, W.; Merwarth, P.; Oneill, M.; Goorevich, C.; Waligora, S.

    1982-01-01

    A source code analyzer program (SAP) designed to assist personnel in conducting studies of FORTRAN programs is described. The SAP scans FORTRAN source code and produces reports that present statistics and measures of statements and structures that make up a module. The processing performed by SAP and of the routines, COMMON blocks, and files used by SAP are described. The system generation procedure for SAP is also presented.

  19. Multidimensional modulation for next-generation transmission systems

    NASA Astrophysics Data System (ADS)

    Millar, David S.; Koike-Akino, Toshiaki; Kojima, Keisuke; Parsons, Kieran

    2017-01-01

    Recent research in multidimensional modulation has shown great promise in long reach applications. In this work, we will investigate the origins of this gain, the different approaches to multidimensional constellation design, and different performance metrics for coded modulation. We will also discuss the reason that such coded modulation schemes seem to have limited application at shorter distances, and the potential for other coded modulation schemes in future transmission systems.

  20. Medical reliable network using concatenated channel codes through GSM network.

    PubMed

    Ahmed, Emtithal; Kohno, Ryuji

    2013-01-01

    Although the 4(th) generation (4G) of global mobile communication network, i.e. Long Term Evolution (LTE) coexisting with the 3(rd) generation (3G) has successfully started; the 2(nd) generation (2G), i.e. Global System for Mobile communication (GSM) still playing an important role in many developing countries. Without any other reliable network infrastructure, GSM can be applied for tele-monitoring applications, where high mobility and low cost are necessary. A core objective of this paper is to introduce the design of a more reliable and dependable Medical Network Channel Code system (MNCC) through GSM Network. MNCC design based on simple concatenated channel code, which is cascade of an inner code (GSM) and an extra outer code (Convolution Code) in order to protect medical data more robust against channel errors than other data using the existing GSM network. In this paper, the MNCC system will provide Bit Error Rate (BER) equivalent to the BER for medical tele monitoring of physiological signals, which is 10(-5) or less. The performance of the MNCC has been proven and investigated using computer simulations under different channels condition such as, Additive White Gaussian Noise (AWGN), Rayleigh noise and burst noise. Generally the MNCC system has been providing better performance as compared to GSM.

  1. Enhanced 2/3 four-ary modulation code using soft-decision Viterbi decoding for four-level holographic data storage systems

    NASA Astrophysics Data System (ADS)

    Kong, Gyuyeol; Choi, Sooyong

    2017-09-01

    An enhanced 2/3 four-ary modulation code using soft-decision Viterbi decoding is proposed for four-level holographic data storage systems. While the previous four-ary modulation codes focus on preventing maximum two-dimensional intersymbol interference patterns, the proposed four-ary modulation code aims at maximizing the coding gains for better bit error rate performances. For achieving significant coding gains from the four-ary modulation codes, we design a new 2/3 four-ary modulation code in order to enlarge the free distance on the trellis through extensive simulation. The free distance of the proposed four-ary modulation code is extended from 1.21 to 2.04 compared with that of the conventional four-ary modulation code. The simulation result shows that the proposed four-ary modulation code has more than 1 dB gains compared with the conventional four-ary modulation code.

  2. Application of artificial neural networks to the design optimization of aerospace structural components

    NASA Technical Reports Server (NTRS)

    Berke, Laszlo; Patnaik, Surya N.; Murthy, Pappu L. N.

    1993-01-01

    The application of artificial neural networks to capture structural design expertise is demonstrated. The principal advantage of a trained neural network is that it requires trivial computational effort to produce an acceptable new design. For the class of problems addressed, the development of a conventional expert system would be extremely difficult. In the present effort, a structural optimization code with multiple nonlinear programming algorithms and an artificial neural network code NETS were used. A set of optimum designs for a ring and two aircraft wings for static and dynamic constraints were generated by using the optimization codes. The optimum design data were processed to obtain input and output pairs, which were used to develop a trained artificial neural network with the code NETS. Optimum designs for new design conditions were predicted by using the trained network. Neural net prediction of optimum designs was found to be satisfactory for most of the output design parameters. However, results from the present study indicate that caution must be exercised to ensure that all design variables are within selected error bounds.

  3. Optimum Design of Aerospace Structural Components Using Neural Networks

    NASA Technical Reports Server (NTRS)

    Berke, L.; Patnaik, S. N.; Murthy, P. L. N.

    1993-01-01

    The application of artificial neural networks to capture structural design expertise is demonstrated. The principal advantage of a trained neural network is that it requires a trivial computational effort to produce an acceptable new design. For the class of problems addressed, the development of a conventional expert system would be extremely difficult. In the present effort, a structural optimization code with multiple nonlinear programming algorithms and an artificial neural network code NETS were used. A set of optimum designs for a ring and two aircraft wings for static and dynamic constraints were generated using the optimization codes. The optimum design data were processed to obtain input and output pairs, which were used to develop a trained artificial neural network using the code NETS. Optimum designs for new design conditions were predicted using the trained network. Neural net prediction of optimum designs was found to be satisfactory for the majority of the output design parameters. However, results from the present study indicate that caution must be exercised to ensure that all design variables are within selected error bounds.

  4. Design of 28 GHz, 200 kW Gyrotron for ECRH Applications

    NASA Astrophysics Data System (ADS)

    Yadav, Vivek; Singh, Udaybir; Kumar, Nitin; Kumar, Anil; Deorani, S. C.; Sinha, A. K.

    2013-01-01

    This paper presents the design of 28 GHz, 200 kW gyrotron for Indian TOKAMAK system. The paper reports the designs of interaction cavity, magnetron injection gun and RF window. EGUN code is used for the optimization of electron gun parameters. TE03 mode is selected as the operating mode by using the in-house developed code GCOMS. The simulation and optimization of the cavity parameters are carried out by using the Particle-in-cell, three dimensional (3-D)-electromagnetic simulation code MAGIC. The output power more than 250 kW is achieved.

  5. Statistical physics inspired energy-efficient coded-modulation for optical communications.

    PubMed

    Djordjevic, Ivan B; Xu, Lei; Wang, Ting

    2012-04-15

    Because Shannon's entropy can be obtained by Stirling's approximation of thermodynamics entropy, the statistical physics energy minimization methods are directly applicable to the signal constellation design. We demonstrate that statistical physics inspired energy-efficient (EE) signal constellation designs, in combination with large-girth low-density parity-check (LDPC) codes, significantly outperform conventional LDPC-coded polarization-division multiplexed quadrature amplitude modulation schemes. We also describe an EE signal constellation design algorithm. Finally, we propose the discrete-time implementation of D-dimensional transceiver and corresponding EE polarization-division multiplexed system. © 2012 Optical Society of America

  6. RELAP-7 Closure Correlations

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

    Zou, Ling; Berry, R. A.; Martineau, R. C.

    The RELAP-7 code is the next generation nuclear reactor system safety analysis code being developed at the Idaho National Laboratory (INL). The code is based on the INL’s modern scientific software development framework, MOOSE (Multi-Physics Object Oriented Simulation Environment). The overall design goal of RELAP-7 is to take advantage of the previous thirty years of advancements in computer architecture, software design, numerical integration methods, and physical models. The end result will be a reactor systems analysis capability that retains and improves upon RELAP5’s and TRACE’s capabilities and extends their analysis capabilities for all reactor system simulation scenarios. The RELAP-7 codemore » utilizes the well-posed 7-equation two-phase flow model for compressible two-phase flow. Closure models used in the TRACE code has been reviewed and selected to reflect the progress made during the past decades and provide a basis for the colure correlations implemented in the RELAP-7 code. This document provides a summary on the closure correlations that are currently implemented in the RELAP-7 code. The closure correlations include sub-grid models that describe interactions between the fluids and the flow channel, and interactions between the two phases.« less

  7. Methods of alleviation of ionospheric scintillation effects on digital communications

    NASA Technical Reports Server (NTRS)

    Massey, J. L.

    1974-01-01

    The degradation of the performance of digital communication systems because of ionospheric scintillation effects can be reduced either by diversity techniques or by coding. The effectiveness of traditional space-diversity, frequency-diversity and time-diversity techniques is reviewed and design considerations isolated. Time-diversity signaling is then treated as an extremely simple form of coding. More advanced coding methods, such as diffuse threshold decoding and burst-trapping decoding, which appear attractive in combatting scintillation effects are discussed and design considerations noted. Finally, adaptive coding techniques appropriate when the general state of the channel is known are discussed.

  8. Modeling and simulation of CANDU reactor and its regulating system

    NASA Astrophysics Data System (ADS)

    Javidnia, Hooman

    Analytical computer codes are indispensable tools in design, optimization, and control of nuclear power plants. Numerous codes have been developed to perform different types of analyses related to the nuclear power plants. A large number of these codes are designed to perform safety analyses. In the context of safety analyses, the control system is often neglected. Although there are good reasons for such a decision, that does not mean that the study of control systems in the nuclear power plants should be neglected altogether. In this thesis, a proof of concept code is developed as a tool that can be used in the design. optimization. and operation stages of the control system. The main objective in the design of this computer code is providing a tool that is easy to use by its target audience and is capable of producing high fidelity results that can be trusted to design the control system and optimize its performance. Since the overall plant control system covers a very wide range of processes, in this thesis the focus has been on one particular module of the the overall plant control system, namely, the reactor regulating system. The center of the reactor regulating system is the CANDU reactor. A nodal model for the reactor is used to represent the spatial neutronic kinetics of the core. The nodal model produces better results compared to the point kinetics model which is often used in the design and analysis of control system for nuclear reactors. The model can capture the spatial effects to some extent. although it is not as detailed as the finite difference methods. The criteria for choosing a nodal model of the core are: (1) the model should provide more detail than point kinetics and capture spatial effects, (2) it should not be too complex or overly detailed to slow down the simulation and provide details that are extraneous or unnecessary for a control engineer. Other than the reactor itself, there are auxiliary models that describe dynamics of different phenomena related to the transfer of the energy from the core. The main function of the reactor regulating system is to control the power of the reactor. This is achieved by using a set of detectors. reactivity devices. and digital control algorithms. Three main reactivity devices that are activated during short-term or intermediate-term transients are modeled in this thesis. The main elements of the digital control system are implemented in accordance to the program specifications for the actual control system in CANDU reactors. The simulation results are validated against requirements of the reactor regulating system. actual plant data. and pre-validated data from other computer codes. The validation process shows that the simulation results can be trusted in making engineering decisions regarding the reactor regulating system and prediction of the system performance in response to upset conditions or disturbances. KEYWORDS: CANDU reactors. reactor regulating system. nodal model. spatial kinetics. reactivity devices. simulation.

  9. GLOBECOM '86 - Global Telecommunications Conference, Houston, TX, Dec. 1-4, 1986, Conference Record. Volumes 1, 2, & 3

    NASA Astrophysics Data System (ADS)

    Papers are presented on local area networks; formal methods for communication protocols; computer simulation of communication systems; spread spectrum and coded communications; tropical radio propagation; VLSI for communications; strategies for increasing software productivity; multiple access communications; advanced communication satellite technologies; and spread spectrum systems. Topics discussed include Space Station communication and tracking development and design; transmission networks; modulation; data communications; computer network protocols and performance; and coding and synchronization. Consideration is given to free space optical communications systems; VSAT communication networks; network topology design; advances in adaptive filtering echo cancellation and adaptive equalization; advanced signal processing for satellite communications; the elements, design, and analysis of fiber-optic networks; and advances in digital microwave systems.

  10. Implementation and Evaluation of Microcomputer Systems for the Republic of Turkey’s Naval Ships.

    DTIC Science & Technology

    1986-03-01

    important database design tool for both logical and physical database design, such as flowcharts or pseudocodes are used for program design. Logical...string manipulation in FORTRAN is difficult but not impossible. BASIC ( Beginners All-Purpose Symbolic Instruction Code): Basic is currently the most...63 APPENDIX B GLOSSARY/ACRONYM LIST AC Alternating Current AP Application Program BASIC Beginners All-purpose Symbolic Instruction Code CCP

  11. 14 CFR Sec. 1-4 - System of accounts coding.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... General Accounting Provisions Sec. 1-4 System of accounts coding. (a) A four digit control number is assigned for each balance sheet and profit and loss account. Each balance sheet account is numbered sequentially, within blocks, designating basic balance sheet classifications. The first two digits of the four...

  12. Advanced Imaging Optics Utilizing Wavefront Coding.

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

    Scrymgeour, David; Boye, Robert; Adelsberger, Kathleen

    2015-06-01

    Image processing offers a potential to simplify an optical system by shifting some of the imaging burden from lenses to the more cost effective electronics. Wavefront coding using a cubic phase plate combined with image processing can extend the system's depth of focus, reducing many of the focus-related aberrations as well as material related chromatic aberrations. However, the optimal design process and physical limitations of wavefront coding systems with respect to first-order optical parameters and noise are not well documented. We examined image quality of simulated and experimental wavefront coded images before and after reconstruction in the presence of noise.more » Challenges in the implementation of cubic phase in an optical system are discussed. In particular, we found that limitations must be placed on system noise, aperture, field of view and bandwidth to develop a robust wavefront coded system.« less

  13. Numerical investigations in three-dimensional internal flows

    NASA Technical Reports Server (NTRS)

    Rose, William C.

    1991-01-01

    In previous efforts, a two-dimensional full Navier-Stokes (FNS) code (SCRAM2D) was used in a design process that involved parametric modifications of the inlet geometry to arrive at what appeared to be an optimum inlet flowfield that produced a uniform flow at the exit in a very short distance. In these previous studies, the technologies for determining the contours with a 'man-in-the-loop' approach for both the ramp and cowl of the inlet were demonstrated, and nearly shock-free exiting flowfields were shown to be obtainable. The resulting two-dimensional compression contours were then used with swept sidewalls to form a three-dimensional inlet. Then the three-dimensional Navier-Stokes code (SCRAM3D) was used to investigate the inlet's three-dimensional flow. One of the major difficulties encountered in the previous studies was that associated with the relatively long time required to obtain a solution using even the 2D FNS code in the design process. Since one of the goals of high-speed inlet design is to produce inputs to the overall aircraft design in a timely manner, it was proposed for this year's research to examine 2D and 3D viscous flow solver techniques alternative to the NFS codes used to date. Areas of the inlet particularly identified for code speed up are those associated with the forebody and external flow ramp systems of the inlet. In these areas, parabolized, or space-marched, Navier-Stokes codes were proposed to be investigated for their applicability in the design process developed previously. This report describes the results of an investigation into the use of two other codes for analyzing the forebody and inlet ramp systems of high-speed inlets.

  14. Solar dynamic power for the Space Station

    NASA Technical Reports Server (NTRS)

    Archer, J. S.; Diamant, E. S.

    1986-01-01

    This paper describes a computer code which provides a significant advance in the systems analysis capabilities of solar dynamic power modules. While the code can be used to advantage in the preliminary analysis of terrestrial solar dynamic modules its real value lies in the adaptions which make it particularly useful for the conceptualization of optimized power modules for space applications. In particular, as illustrated in the paper, the code can be used to establish optimum values of concentrator diameter, concentrator surface roughness, concentrator rim angle and receiver aperture corresponding to the main heat cycle options - Organic Rankine and Brayton - and for certain receiver design options. The code can also be used to establish system sizing margins to account for the loss of reflectivity in orbit or the seasonal variation of insolation. By the simulation of the interactions among the major components of a solar dynamic module and through simplified formulations of the major thermal-optic-thermodynamic interactions the code adds a powerful, efficient and economic analytical tool to the repertory of techniques available for the design of advanced space power systems.

  15. Computer algorithm for coding gain

    NASA Technical Reports Server (NTRS)

    Dodd, E. E.

    1974-01-01

    Development of a computer algorithm for coding gain for use in an automated communications link design system. Using an empirical formula which defines coding gain as used in space communications engineering, an algorithm is constructed on the basis of available performance data for nonsystematic convolutional encoding with soft-decision (eight-level) Viterbi decoding.

  16. 29 CFR 1910.119 - Process safety management of highly hazardous chemicals.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... complexity of the process will influence the decision as to the appropriate PHA methodology to use. All PHA... process hazard analysis in sufficient detail to support the analysis. (3) Information pertaining to the...) Relief system design and design basis; (E) Ventilation system design; (F) Design codes and standards...

  17. 29 CFR 1910.119 - Process safety management of highly hazardous chemicals.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... complexity of the process will influence the decision as to the appropriate PHA methodology to use. All PHA... process hazard analysis in sufficient detail to support the analysis. (3) Information pertaining to the...) Relief system design and design basis; (E) Ventilation system design; (F) Design codes and standards...

  18. User's manual for the Heat Pipe Space Radiator design and analysis Code (HEPSPARC)

    NASA Technical Reports Server (NTRS)

    Hainley, Donald C.

    1991-01-01

    A heat pipe space radiatior code (HEPSPARC), was written for the NASA Lewis Research Center and is used for the design and analysis of a radiator that is constructed from a pumped fluid loop that transfers heat to the evaporative section of heat pipes. This manual is designed to familiarize the user with this new code and to serve as a reference for its use. This manual documents the completed work and is intended to be the first step towards verification of the HEPSPARC code. Details are furnished to provide a description of all the requirements and variables used in the design and analysis of a combined pumped loop/heat pipe radiator system. A description of the subroutines used in the program is furnished for those interested in understanding its detailed workings.

  19. Improved Simplified Methods for Effective Seismic Analysis and Design of Isolated and Damped Bridges in Western and Eastern North America

    NASA Astrophysics Data System (ADS)

    Koval, Viacheslav

    The seismic design provisions of the CSA-S6 Canadian Highway Bridge Design Code and the AASHTO LRFD Seismic Bridge Design Specifications have been developed primarily based on historical earthquake events that have occurred along the west coast of North America. For the design of seismic isolation systems, these codes include simplified analysis and design methods. The appropriateness and range of application of these methods are investigated through extensive parametric nonlinear time history analyses in this thesis. It was found that there is a need to adjust existing design guidelines to better capture the expected nonlinear response of isolated bridges. For isolated bridges located in eastern North America, new damping coefficients are proposed. The applicability limits of the code-based simplified methods have been redefined to ensure that the modified method will lead to conservative results and that a wider range of seismically isolated bridges can be covered by this method. The possibility of further improving current simplified code methods was also examined. By transforming the quantity of allocated energy into a displacement contribution, an idealized analytical solution is proposed as a new simplified design method. This method realistically reflects the effects of ground-motion and system design parameters, including the effects of a drifted oscillation center. The proposed method is therefore more appropriate than current existing simplified methods and can be applicable to isolation systems exhibiting a wider range of properties. A multi-level-hazard performance matrix has been adopted by different seismic provisions worldwide and will be incorporated into the new edition of the Canadian CSA-S6-14 Bridge Design code. However, the combined effect and optimal use of isolation and supplemental damping devices in bridges have not been fully exploited yet to achieve enhanced performance under different levels of seismic hazard. A novel Dual-Level Seismic Protection (DLSP) concept is proposed and developed in this thesis which permits to achieve optimum seismic performance with combined isolation and supplemental damping devices in bridges. This concept is shown to represent an attractive design approach for both the upgrade of existing seismically deficient bridges and the design of new isolated bridges.

  20. Modeling Improvements and Users Manual for Axial-flow Turbine Off-design Computer Code AXOD

    NASA Technical Reports Server (NTRS)

    Glassman, Arthur J.

    1994-01-01

    An axial-flow turbine off-design performance computer code used for preliminary studies of gas turbine systems was modified and calibrated based on the experimental performance of large aircraft-type turbines. The flow- and loss-model modifications and calibrations are presented in this report. Comparisons are made between computed performances and experimental data for seven turbines over wide ranges of speed and pressure ratio. This report also serves as the users manual for the revised code, which is named AXOD.

  1. New Gear Transmission Error Measurement System Designed

    NASA Technical Reports Server (NTRS)

    Oswald, Fred B.

    2001-01-01

    The prime source of vibration and noise in a gear system is the transmission error between the meshing gears. Transmission error is caused by manufacturing inaccuracy, mounting errors, and elastic deflections under load. Gear designers often attempt to compensate for transmission error by modifying gear teeth. This is done traditionally by a rough "rule of thumb" or more recently under the guidance of an analytical code. In order for a designer to have confidence in a code, the code must be validated through experiment. NASA Glenn Research Center contracted with the Design Unit of the University of Newcastle in England for a system to measure the transmission error of spur and helical test gears in the NASA Gear Noise Rig. The new system measures transmission error optically by means of light beams directed by lenses and prisms through gratings mounted on the gear shafts. The amount of light that passes through both gratings is directly proportional to the transmission error of the gears. A photodetector circuit converts the light to an analog electrical signal. To increase accuracy and reduce "noise" due to transverse vibration, there are parallel light paths at the top and bottom of the gears. The two signals are subtracted via differential amplifiers in the electronics package. The output of the system is 40 mV/mm, giving a resolution in the time domain of better than 0.1 mm, and discrimination in the frequency domain of better than 0.01 mm. The new system will be used to validate gear analytical codes and to investigate mechanisms that produce vibration and noise in parallel axis gears.

  2. Ultra-wideband communication system prototype using orthogonal frequency coded SAW correlators.

    PubMed

    Gallagher, Daniel R; Kozlovski, Nikolai Y; Malocha, Donald C

    2013-03-01

    This paper presents preliminary ultra-wideband (UWB) communication system results utilizing orthogonal frequency coded SAW correlators. Orthogonal frequency coding (OFC) and pseudo-noise (PN) coding provides a means for spread-spectrum UWB. The use of OFC spectrally spreads a PN sequence beyond that of CDMA; allowing for improved correlation gain. The transceiver approach is still very similar to that of the CDMA approach, but provides greater code diversity. Use of SAW correlators eliminates many of the costly components that are typically needed in the intermediate frequency (IF) section in the transmitter and receiver, and greatly reduces the signal processing requirements. Development and results of an experimental prototype system with center frequency of 250 MHz are presented. The prototype system is configured using modular RF components and benchtop pulse generator and frequency source. The SAW correlation filters used in the test setup were designed using 7 chip frequencies within the transducer. The fractional bandwidth of approximately 29% was implemented to exceed the defined UWB specification. Discussion of the filter design and results are presented and are compared with packaged device measurements. A prototype UWB system using OFC SAW correlators is demonstrated in wired and wireless configurations. OFC-coded SAW filters are used for generation of a transmitted spread-spectrum UWB and matched filter correlated reception. Autocorrelation and cross-correlation system outputs are compared. The results demonstrate the feasibility of UWB SAW correlators for use in UWB communication transceivers.

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

    NASA Technical Reports Server (NTRS)

    1989-01-01

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

  4. Engineering High Assurance Distributed Cyber Physical Systems

    DTIC Science & Technology

    2015-01-15

    decisions: number of interacting agents and co-dependent decisions made in real-time without causing interference . To engineer a high assurance DART...environment specification, architecture definition, domain-specific languages, design patterns, code - generation, analysis, test-generation, and simulation...include synchronization between the models and source code , debugging at the model level, expression of the design intent, and quality of service

  5. Low complexity Reed-Solomon-based low-density parity-check design for software defined optical transmission system based on adaptive puncturing decoding algorithm

    NASA Astrophysics Data System (ADS)

    Pan, Xiaolong; Liu, Bo; Zheng, Jianglong; Tian, Qinghua

    2016-08-01

    We propose and demonstrate a low complexity Reed-Solomon-based low-density parity-check (RS-LDPC) code with adaptive puncturing decoding algorithm for elastic optical transmission system. Partial received codes and the relevant column in parity-check matrix can be punctured to reduce the calculation complexity by adaptive parity-check matrix during decoding process. The results show that the complexity of the proposed decoding algorithm is reduced by 30% compared with the regular RS-LDPC system. The optimized code rate of the RS-LDPC code can be obtained after five times iteration.

  6. Multi-level Expression Design Language: Requirement level (MEDL-R) system evaluation

    NASA Technical Reports Server (NTRS)

    1980-01-01

    An evaluation of the Multi-Level Expression Design Language Requirements Level (MEDL-R) system was conducted to determine whether it would be of use in the Goddard Space Flight Center Code 580 software development environment. The evaluation is based upon a study of the MEDL-R concept of requirement languages, the functions performed by MEDL-R, and the MEDL-R language syntax. Recommendations are made for changes to MEDL-R that would make it useful in the Code 580 environment.

  7. An Object-Oriented Computer Code for Aircraft Engine Weight Estimation

    NASA Technical Reports Server (NTRS)

    Tong, Michael T.; Naylor, Bret A.

    2009-01-01

    Reliable engine-weight estimation at the conceptual design stage is critical to the development of new aircraft engines. It helps to identify the best engine concept amongst several candidates. At NASA Glenn Research Center (GRC), the Weight Analysis of Turbine Engines (WATE) computer code, originally developed by Boeing Aircraft, has been used to estimate the engine weight of various conceptual engine designs. The code, written in FORTRAN, was originally developed for NASA in 1979. Since then, substantial improvements have been made to the code to improve the weight calculations for most of the engine components. Most recently, to improve the maintainability and extensibility of WATE, the FORTRAN code has been converted into an object-oriented version. The conversion was done within the NASA's NPSS (Numerical Propulsion System Simulation) framework. This enables WATE to interact seamlessly with the thermodynamic cycle model which provides component flow data such as airflows, temperatures, and pressures, etc., that are required for sizing the components and weight calculations. The tighter integration between the NPSS and WATE would greatly enhance system-level analysis and optimization capabilities. It also would facilitate the enhancement of the WATE code for next-generation aircraft and space propulsion systems. In this paper, the architecture of the object-oriented WATE code (or WATE++) is described. Both the FORTRAN and object-oriented versions of the code are employed to compute the dimensions and weight of a 300-passenger aircraft engine (GE90 class). Both versions of the code produce essentially identical results as should be the case.

  8. Assume-Guarantee Verification of Source Code with Design-Level Assumptions

    NASA Technical Reports Server (NTRS)

    Giannakopoulou, Dimitra; Pasareanu, Corina S.; Cobleigh, Jamieson M.

    2004-01-01

    Model checking is an automated technique that can be used to determine whether a system satisfies certain required properties. To address the 'state explosion' problem associated with this technique, we propose to integrate assume-guarantee verification at different phases of system development. During design, developers build abstract behavioral models of the system components and use them to establish key properties of the system. To increase the scalability of model checking at this level, we have developed techniques that automatically decompose the verification task by generating component assumptions for the properties to hold. The design-level artifacts are subsequently used to guide the implementation of the system, but also to enable more efficient reasoning at the source code-level. In particular we propose to use design-level assumptions to similarly decompose the verification of the actual system implementation. We demonstrate our approach on a significant NASA application, where design-level models were used to identify; and correct a safety property violation, and design-level assumptions allowed us to check successfully that the property was presented by the implementation.

  9. Phase-lock-loop application for fiber optic receiver

    NASA Astrophysics Data System (ADS)

    Ruggles, Stephen L.; Wills, Robert W.

    1991-02-01

    Phase-locked loop circuits are frequently employed in communication systems. In recent years, digital phase-locked loop circuits were utilized in optical communications systems. In an optical transceiver system, the digital phase-locked loop circuit is connected to the output of the receiver to extract a clock signal from the received coded data (NRZ, Bi-Phase, or Manchester). The clock signal is then used to reconstruct or recover the original data from the coded data. A theoretical approach to the design of a digital phase-locked loop circuit operation at 1 and 50 MHz is described. Hardware implementation of a breadboard design to function at 1 MHz and a printed-circuit board designed to function at 50 MHz were assembled using emitter coupled logic (ECL) to verify experimentally the theoretical design.

  10. Phase-lock-loop application for fiber optic receiver

    NASA Technical Reports Server (NTRS)

    Ruggles, Stephen L.; Wills, Robert W.

    1991-01-01

    Phase-locked loop circuits are frequently employed in communication systems. In recent years, digital phase-locked loop circuits were utilized in optical communications systems. In an optical transceiver system, the digital phase-locked loop circuit is connected to the output of the receiver to extract a clock signal from the received coded data (NRZ, Bi-Phase, or Manchester). The clock signal is then used to reconstruct or recover the original data from the coded data. A theoretical approach to the design of a digital phase-locked loop circuit operation at 1 and 50 MHz is described. Hardware implementation of a breadboard design to function at 1 MHz and a printed-circuit board designed to function at 50 MHz were assembled using emitter coupled logic (ECL) to verify experimentally the theoretical design.

  11. Database System Design and Implementation for Marine Air-Traffic-Controller Training

    DTIC Science & Technology

    2017-06-01

    NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA THESIS Approved for public release. Distribution is unlimited. DATABASE SYSTEM DESIGN AND...thesis 4. TITLE AND SUBTITLE DATABASE SYSTEM DESIGN AND IMPLEMENTATION FOR MARINE AIR-TRAFFIC-CONTROLLER TRAINING 5. FUNDING NUMBERS 6. AUTHOR(S...12b. DISTRIBUTION CODE 13. ABSTRACT (maximum 200 words) This project focused on the design , development, and implementation of a centralized

  12. FPGA implementation of high-performance QC-LDPC decoder for optical communications

    NASA Astrophysics Data System (ADS)

    Zou, Ding; Djordjevic, Ivan B.

    2015-01-01

    Forward error correction is as one of the key technologies enabling the next-generation high-speed fiber optical communications. Quasi-cyclic (QC) low-density parity-check (LDPC) codes have been considered as one of the promising candidates due to their large coding gain performance and low implementation complexity. In this paper, we present our designed QC-LDPC code with girth 10 and 25% overhead based on pairwise balanced design. By FPGAbased emulation, we demonstrate that the 5-bit soft-decision LDPC decoder can achieve 11.8dB net coding gain with no error floor at BER of 10-15 avoiding using any outer code or post-processing method. We believe that the proposed single QC-LDPC code is a promising solution for 400Gb/s optical communication systems and beyond.

  13. Thermal-hydraulic modeling needs for passive reactors

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

    Kelly, J.M.

    1997-07-01

    The U.S. Nuclear Regulatory Commission has received an application for design certification from the Westinghouse Electric Corporation for an Advanced Light Water Reactor design known as the AP600. As part of the design certification process, the USNRC uses its thermal-hydraulic system analysis codes to independently audit the vendor calculations. The focus of this effort has been the small break LOCA transients that rely upon the passive safety features of the design to depressurize the primary system sufficiently so that gravity driven injection can provide a stable source for long term cooling. Of course, large break LOCAs have also been considered,more » but as the involved phenomena do not appear to be appreciably different from those of current plants, they were not discussed in this paper. Although the SBLOCA scenario does not appear to threaten core coolability - indeed, heatup is not even expected to occur - there have been concerns as to the performance of the passive safety systems. For example, the passive systems drive flows with small heads, consequently requiring more precision in the analysis compared to active systems methods for passive plants as compared to current plants with active systems. For the analysis of SBLOCAs and operating transients, the USNRC uses the RELAP5 thermal-hydraulic system analysis code. To assure the applicability of RELAP5 to the analysis of these transients for the AP600 design, a four year long program of code development and assessment has been undertaken.« less

  14. Guidance, navigation, and control subsystem equipment selection algorithm using expert system methods

    NASA Technical Reports Server (NTRS)

    Allen, Cheryl L.

    1991-01-01

    Enhanced engineering tools can be obtained through the integration of expert system methodologies and existing design software. The application of these methodologies to the spacecraft design and cost model (SDCM) software provides an improved technique for the selection of hardware for unmanned spacecraft subsystem design. The knowledge engineering system (KES) expert system development tool was used to implement a smarter equipment section algorithm than that which is currently achievable through the use of a standard data base system. The guidance, navigation, and control subsystems of the SDCM software was chosen as the initial subsystem for implementation. The portions of the SDCM code which compute the selection criteria and constraints remain intact, and the expert system equipment selection algorithm is embedded within this existing code. The architecture of this new methodology is described and its implementation is reported. The project background and a brief overview of the expert system is described, and once the details of the design are characterized, an example of its implementation is demonstrated.

  15. NSDann2BS, a neutron spectrum unfolding code based on neural networks technology and two bonner spheres

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

    Ortiz-Rodriguez, J. M.; Reyes Alfaro, A.; Reyes Haro, A.

    In this work a neutron spectrum unfolding code, based on artificial intelligence technology is presented. The code called ''Neutron Spectrometry and Dosimetry with Artificial Neural Networks and two Bonner spheres'', (NSDann2BS), was designed in a graphical user interface under the LabVIEW programming environment. The main features of this code are to use an embedded artificial neural network architecture optimized with the ''Robust design of artificial neural networks methodology'' and to use two Bonner spheres as the only piece of information. In order to build the code here presented, once the net topology was optimized and properly trained, knowledge stored atmore » synaptic weights was extracted and using a graphical framework build on the LabVIEW programming environment, the NSDann2BS code was designed. This code is friendly, intuitive and easy to use for the end user. The code is freely available upon request to authors. To demonstrate the use of the neural net embedded in the NSDann2BS code, the rate counts of {sup 252}Cf, {sup 241}AmBe and {sup 239}PuBe neutron sources measured with a Bonner spheres system.« less

  16. NSDann2BS, a neutron spectrum unfolding code based on neural networks technology and two bonner spheres

    NASA Astrophysics Data System (ADS)

    Ortiz-Rodríguez, J. M.; Reyes Alfaro, A.; Reyes Haro, A.; Solís Sánches, L. O.; Miranda, R. Castañeda; Cervantes Viramontes, J. M.; Vega-Carrillo, H. R.

    2013-07-01

    In this work a neutron spectrum unfolding code, based on artificial intelligence technology is presented. The code called "Neutron Spectrometry and Dosimetry with Artificial Neural Networks and two Bonner spheres", (NSDann2BS), was designed in a graphical user interface under the LabVIEW programming environment. The main features of this code are to use an embedded artificial neural network architecture optimized with the "Robust design of artificial neural networks methodology" and to use two Bonner spheres as the only piece of information. In order to build the code here presented, once the net topology was optimized and properly trained, knowledge stored at synaptic weights was extracted and using a graphical framework build on the LabVIEW programming environment, the NSDann2BS code was designed. This code is friendly, intuitive and easy to use for the end user. The code is freely available upon request to authors. To demonstrate the use of the neural net embedded in the NSDann2BS code, the rate counts of 252Cf, 241AmBe and 239PuBe neutron sources measured with a Bonner spheres system.

  17. FRANOPP: Framework for analysis and optimization problems user's guide

    NASA Technical Reports Server (NTRS)

    Riley, K. M.

    1981-01-01

    Framework for analysis and optimization problems (FRANOPP) is a software aid for the study and solution of design (optimization) problems which provides the driving program and plotting capability for a user generated programming system. In addition to FRANOPP, the programming system also contains the optimization code CONMIN, and two user supplied codes, one for analysis and one for output. With FRANOPP the user is provided with five options for studying a design problem. Three of the options utilize the plot capability and present an indepth study of the design problem. The study can be focused on a history of the optimization process or on the interaction of variables within the design problem.

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

    Guo, Z.; Zweibaum, N.; Shao, M.

    The University of California, Berkeley (UCB) is performing thermal hydraulics safety analysis to develop the technical basis for design and licensing of fluoride-salt-cooled, high-temperature reactors (FHRs). FHR designs investigated by UCB use natural circulation for emergency, passive decay heat removal when normal decay heat removal systems fail. The FHR advanced natural circulation analysis (FANCY) code has been developed for assessment of passive decay heat removal capability and safety analysis of these innovative system designs. The FANCY code uses a one-dimensional, semi-implicit scheme to solve for pressure-linked mass, momentum and energy conservation equations. Graph theory is used to automatically generate amore » staggered mesh for complicated pipe network systems. Heat structure models have been implemented for three types of boundary conditions (Dirichlet, Neumann and Robin boundary conditions). Heat structures can be composed of several layers of different materials, and are used for simulation of heat structure temperature distribution and heat transfer rate. Control models are used to simulate sequences of events or trips of safety systems. A proportional-integral controller is also used to automatically make thermal hydraulic systems reach desired steady state conditions. A point kinetics model is used to model reactor kinetics behavior with temperature reactivity feedback. The underlying large sparse linear systems in these models are efficiently solved by using direct and iterative solvers provided by the SuperLU code on high performance machines. Input interfaces are designed to increase the flexibility of simulation for complicated thermal hydraulic systems. In conclusion, this paper mainly focuses on the methodology used to develop the FANCY code, and safety analysis of the Mark 1 pebble-bed FHR under development at UCB is performed.« less

  19. Run-length encoding graphic rules, biochemically editable designs and steganographical numeric data embedment for DNA-based cryptographical coding system.

    PubMed

    Kawano, Tomonori

    2013-03-01

    There have been a wide variety of approaches for handling the pieces of DNA as the "unplugged" tools for digital information storage and processing, including a series of studies applied to the security-related area, such as DNA-based digital barcodes, water marks and cryptography. In the present article, novel designs of artificial genes as the media for storing the digitally compressed data for images are proposed for bio-computing purpose while natural genes principally encode for proteins. Furthermore, the proposed system allows cryptographical application of DNA through biochemically editable designs with capacity for steganographical numeric data embedment. As a model case of image-coding DNA technique application, numerically and biochemically combined protocols are employed for ciphering the given "passwords" and/or secret numbers using DNA sequences. The "passwords" of interest were decomposed into single letters and translated into the font image coded on the separate DNA chains with both the coding regions in which the images are encoded based on the novel run-length encoding rule, and the non-coding regions designed for biochemical editing and the remodeling processes revealing the hidden orientation of letters composing the original "passwords." The latter processes require the molecular biological tools for digestion and ligation of the fragmented DNA molecules targeting at the polymerase chain reaction-engineered termini of the chains. Lastly, additional protocols for steganographical overwriting of the numeric data of interests over the image-coding DNA are also discussed.

  20. 78 FR 52907 - Fees for Reviews of the Rule Enforcement Programs of Designated Contract Markets and Registered...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-27

    ... Activity Codes (BPAC) system, formerly the Management Accounting Structure Codes (MASC) system, which... markets and registered futures associations to recover the costs incurred by the Commission in the... average of actual program costs incurred during FY 2010, 2011, and 2012. DATES: Effective date: Each SRO...

  1. General RMP Guidance - Appendix B: Selected NAICS Codes

    EPA Pesticide Factsheets

    This appendix contains a list of selected 2002 North American Industry Classification System (NAICS) codes used by Federal statistical agencies, in designating business types or functions in categories such as farming, manufacturing, and waste management.

  2. Modified NASA-Lewis chemical equilibrium code for MHD applications

    NASA Technical Reports Server (NTRS)

    Sacks, R. A.; Geyer, H. K.; Grammel, S. J.; Doss, E. D.

    1979-01-01

    A substantially modified version of the NASA-Lewis Chemical Equilibrium Code was recently developed. The modifications were designed to extend the power and convenience of the Code as a tool for performing combustor analysis for MHD systems studies. The effect of the programming details is described from a user point of view.

  3. Electromagnetic code for naval applications

    NASA Astrophysics Data System (ADS)

    Crescimbeni, F.; Bessi, F.; Chiti, S.

    1988-12-01

    The use of an increasing number of electronic apparatus became vital to meet the high performance required for military Navy applications. Thus the number of antennas to be mounted on shipboard greatly increased. As a consequence of the high antenna density, of the complexity of the shipboard environment and of the powers used for communication and radar systems, the EMC (Electro-Magnetic Compatibility) problem is playing a leading role in the design of the topside of a ship. The Italian Navy has acquired a numerical code for the antenna siting and design. This code, together with experimental data measured at the Italian Navy test range facility, allows for the evaluation of optimal sitings for antenna systems on shipboard, and the prediction of their performances in the actual environment. The structure of this code, named Programma Elettromagnetico per Applicazioni Navali, (Electromagnetic Code for Naval Applications) is discussed, together with its capabilities and applications. Also the results obtained in some examples are presented and compared with the measurements.

  4. Study on Full Supply Chain Quality and Safetytraceability Systems For Cereal And Oilproducts

    NASA Astrophysics Data System (ADS)

    Liu, Shihong; Zheng, Huoguo; Meng, Hong; Hu, Haiyan; Wu, Jiangshou; Li, Chunhua

    Global food industry and Governments in many countries are putting increasing emphasis on establishment of food traceability systems. Food traceability has become an effective way in food safety management. Aimed at the major quality problems of cereal and oil products existing in the production, processing, warehousing, distribution and other links in the supply chain, this paper firstly proposes a new traceability framework combines the information flow with critical control points and quality indicators. Then it introduces traceability database design and data access mode to realize the framework. In practice, Code design for tracing goods is a challenge thing, so this paper put forward a code system based on UCC/EAN-128 standard.Middleware and Electronic terminal design are also briefly introduced to accomplish traceability system for cereal and oil products.

  5. Error floor behavior study of LDPC codes for concatenated codes design

    NASA Astrophysics Data System (ADS)

    Chen, Weigang; Yin, Liuguo; Lu, Jianhua

    2007-11-01

    Error floor behavior of low-density parity-check (LDPC) codes using quantized decoding algorithms is statistically studied with experimental results on a hardware evaluation platform. The results present the distribution of the residual errors after decoding failure and reveal that the number of residual error bits in a codeword is usually very small using quantized sum-product (SP) algorithm. Therefore, LDPC code may serve as the inner code in a concatenated coding system with a high code rate outer code and thus an ultra low error floor can be achieved. This conclusion is also verified by the experimental results.

  6. Design and System Implications of a Family of Wideband HF Data Waveforms

    DTIC Science & Technology

    2010-09-01

    code rates (i.e. 8/9, 9/10) will be used to attain the highest data rates for surface wave links. Very high puncturing of convolutional codes can...Communication Links”, Edition 1, North Atlantic Treaty Organization, 2009. [14] Yasuda, Y., Kashiki, K., Hirata, Y. “High- Rate Punctured Convolutional Codes ...length 7 convolutional code that has been used for over two decades in 110A. In addition, repetition coding and puncturing was

  7. Requirements for migration of NSSD code systems from LTSS to NLTSS

    NASA Technical Reports Server (NTRS)

    Pratt, M.

    1984-01-01

    The purpose of this document is to address the requirements necessary for a successful conversion of the Nuclear Design (ND) application code systems to the NLTSS environment. The ND application code system community can be characterized as large-scale scientific computation carried out on supercomputers. NLTSS is a distributed operating system being developed at LLNL to replace the LTSS system currently in use. The implications of change are examined including a description of the computational environment and users in ND. The discussion then turns to requirements, first in a general way, followed by specific requirements, including a proposal for managing the transition.

  8. California State Library: Processing Center Design and Specifications. Volume III, Coding Manual.

    ERIC Educational Resources Information Center

    Sherman, Don; Shoffner, Ralph M.

    As part of the report on the California State Library Processing Center design and specifications, this volume is a coding manual for the conversion of catalog card data to a machine-readable form. The form is compatible with the national MARC system, while at the same time it contains provisions for problems peculiar to the local situation. This…

  9. An address geocoding method for improving rural spatial information infrastructure

    NASA Astrophysics Data System (ADS)

    Pan, Yuchun; Chen, Baisong; Lu, Zhou; Li, Shuhua; Zhang, Jingbo; Zhou, YanBing

    2010-11-01

    The transition of rural and agricultural management from divisional to integrated mode has highlighted the importance of data integration and sharing. Current data are mostly collected by specific department to satisfy their own needs and lake of considering on wider potential uses. This led to great difference in data format, semantic, and precision even in same area, which is a significant barrier for constructing an integrated rural spatial information system to support integrated management and decision-making. Considering the rural cadastral management system and postal zones, the paper designs a rural address geocoding method based on rural cadastral parcel. It puts forward a geocoding standard which consists of absolute position code, relative position code and extended code. It designs a rural geocoding database model, and addresses collection and update model. Then, based on the rural address geocoding model, it proposed a data model for rural agricultural resources management. The results show that the address coding based on postal code is stable and easy to memorize, two-dimensional coding based on the direction and distance is easy to be located and memorized, while extended code can enhance the extensibility and flexibility of address geocoding.

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

    NASA Technical Reports Server (NTRS)

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

    1986-01-01

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

  11. User's manual for the BNW-I optimization code for dry-cooled power plants. [AMCIRC

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

    Braun, D.J.; Daniel, D.J.; De Mier, W.V.

    1977-01-01

    This appendix provides a listing, called Program AMCIRC, of the BNW-1 optimization code for determining, for a particular size power plant, the optimum dry cooling tower design using ammonia flow in the heat exchanger tubes. The optimum design is determined by repeating the design of the cooling system over a range of design conditions in order to find the cooling system with the smallest incremental cost. This is accomplished by varying five parameters of the plant and cooling system over ranges of values. These parameters are varied systematically according to techniques that perform pattern and gradient searches. The dry coolingmore » system optimized by program AMCIRC is composed of a condenser/reboiler (condensation of steam and boiling of ammonia), piping system (transports ammonia vapor out and ammonia liquid from the dry cooling towers), and circular tower system (vertical one-pass heat exchangers situated in circular configurations with cocurrent ammonia flow in the tubes of the heat exchanger). (LCL)« less

  12. Performance and Feasibility Analysis of a Wind Turbine Power System for Use on Mars

    NASA Technical Reports Server (NTRS)

    Lichter, Matthew D.; Viterna, Larry

    1999-01-01

    A wind turbine power system for future missions to the Martian surface was studied for performance and feasibility. A C++ program was developed from existing FORTRAN code to analyze the power capabilities of wind turbines under different environments and design philosophies. Power output, efficiency, torque, thrust, and other performance criteria could be computed given design geometries, atmospheric conditions, and airfoil behavior. After reviewing performance of such a wind turbine, a conceptual system design was modeled to evaluate feasibility. More analysis code was developed to study and optimize the overall structural design. Findings of this preliminary study show that turbine power output on Mars could be as high as several hundred kilowatts. The optimized conceptual design examined here would have a power output of 104 kW, total mass of 1910 kg, and specific power of 54.6 W/kg.

  13. Insertion of operation-and-indicate instructions for optimized SIMD code

    DOEpatents

    Eichenberger, Alexander E; Gara, Alan; Gschwind, Michael K

    2013-06-04

    Mechanisms are provided for inserting indicated instructions for tracking and indicating exceptions in the execution of vectorized code. A portion of first code is received for compilation. The portion of first code is analyzed to identify non-speculative instructions performing designated non-speculative operations in the first code that are candidates for replacement by replacement operation-and-indicate instructions that perform the designated non-speculative operations and further perform an indication operation for indicating any exception conditions corresponding to special exception values present in vector register inputs to the replacement operation-and-indicate instructions. The replacement is performed and second code is generated based on the replacement of the at least one non-speculative instruction. The data processing system executing the compiled code is configured to store special exception values in vector output registers, in response to a speculative instruction generating an exception condition, without initiating exception handling.

  14. Computer aided system for parametric design of combination die

    NASA Astrophysics Data System (ADS)

    Naranje, Vishal G.; Hussein, H. M. A.; Kumar, S.

    2017-09-01

    In this paper, a computer aided system for parametric design of combination dies is presented. The system is developed using knowledge based system technique of artificial intelligence. The system is capable to design combination dies for production of sheet metal parts having punching and cupping operations. The system is coded in Visual Basic and interfaced with AutoCAD software. The low cost of the proposed system will help die designers of small and medium scale sheet metal industries for design of combination dies for similar type of products. The proposed system is capable to reduce design time and efforts of die designers for design of combination dies.

  15. Architecture-driven reuse of code in KASE

    NASA Technical Reports Server (NTRS)

    Bhansali, Sanjay

    1993-01-01

    In order to support the synthesis of large, complex software systems, we need to focus on issues pertaining to the architectural design of a system in addition to algorithm and data structure design. An approach that is based on abstracting the architectural design of a set of problems in the form of a generic architecture, and providing tools that can be used to instantiate the generic architecture for specific problem instances is presented. Such an approach also facilitates reuse of code between different systems belonging to the same problem class. An application of our approach on a realistic problem is described; the results of the exercise are presented; and how our approach compares to other work in this area is discussed.

  16. Multidisciplinary High-Fidelity Analysis and Optimization of Aerospace Vehicles. Part 1; Formulation

    NASA Technical Reports Server (NTRS)

    Walsh, J. L.; Townsend, J. C.; Salas, A. O.; Samareh, J. A.; Mukhopadhyay, V.; Barthelemy, J.-F.

    2000-01-01

    An objective of the High Performance Computing and Communication Program at the NASA Langley Research Center is to demonstrate multidisciplinary shape and sizing optimization of a complete aerospace vehicle configuration by using high-fidelity, finite element structural analysis and computational fluid dynamics aerodynamic analysis in a distributed, heterogeneous computing environment that includes high performance parallel computing. A software system has been designed and implemented to integrate a set of existing discipline analysis codes, some of them computationally intensive, into a distributed computational environment for the design of a highspeed civil transport configuration. The paper describes the engineering aspects of formulating the optimization by integrating these analysis codes and associated interface codes into the system. The discipline codes are integrated by using the Java programming language and a Common Object Request Broker Architecture (CORBA) compliant software product. A companion paper presents currently available results.

  17. Code CUGEL: A code to unfold Ge(Li) spectrometer polyenergetic gamma photon experimental distributions

    NASA Technical Reports Server (NTRS)

    Steyn, J. J.; Born, U.

    1970-01-01

    A FORTRAN code was developed for the Univac 1108 digital computer to unfold lithium-drifted germanium semiconductor spectrometers, polyenergetic gamma photon experimental distributions. It was designed to analyze the combination continuous and monoenergetic gamma radiation field of radioisotope volumetric sources. The code generates the detector system response matrix function and applies it to monoenergetic spectral components discretely and to the continuum iteratively. It corrects for system drift, source decay, background, and detection efficiency. Results are presented in digital form for differential and integrated photon number and energy distributions, and for exposure dose.

  18. Tunable wavefront coded imaging system based on detachable phase mask: Mathematical analysis, optimization and underlying applications

    NASA Astrophysics Data System (ADS)

    Zhao, Hui; Wei, Jingxuan

    2014-09-01

    The key to the concept of tunable wavefront coding lies in detachable phase masks. Ojeda-Castaneda et al. (Progress in Electronics Research Symposium Proceedings, Cambridge, USA, July 5-8, 2010) described a typical design in which two components with cosinusoidal phase variation operate together to make defocus sensitivity tunable. The present study proposes an improved design and makes three contributions: (1) A mathematical derivation based on the stationary phase method explains why the detachable phase mask of Ojeda-Castaneda et al. tunes the defocus sensitivity. (2) The mathematical derivations show that the effective bandwidth wavefront coded imaging system is also tunable by making each component of the detachable phase mask move asymmetrically. An improved Fisher information-based optimization procedure was also designed to ascertain the optimal mask parameters corresponding to specific bandwidth. (3) Possible applications of the tunable bandwidth are demonstrated by simulated imaging.

  19. Coding, testing and documentation of processors for the flight design system

    NASA Technical Reports Server (NTRS)

    1980-01-01

    The general functional design and implementation of processors for a space flight design system are briefly described. Discussions of a basetime initialization processor; conic, analytical, and precision coasting flight processors; and an orbit lifetime processor are included. The functions of several utility routines are also discussed.

  20. On decoding of multi-level MPSK modulation codes

    NASA Technical Reports Server (NTRS)

    Lin, Shu; Gupta, Alok Kumar

    1990-01-01

    The decoding problem of multi-level block modulation codes is investigated. The hardware design of soft-decision Viterbi decoder for some short length 8-PSK block modulation codes is presented. An effective way to reduce the hardware complexity of the decoder by reducing the branch metric and path metric, using a non-uniform floating-point to integer mapping scheme, is proposed and discussed. The simulation results of the design are presented. The multi-stage decoding (MSD) of multi-level modulation codes is also investigated. The cases of soft-decision and hard-decision MSD are considered and their performance are evaluated for several codes of different lengths and different minimum squared Euclidean distances. It is shown that the soft-decision MSD reduces the decoding complexity drastically and it is suboptimum. The hard-decision MSD further simplifies the decoding while still maintaining a reasonable coding gain over the uncoded system, if the component codes are chosen properly. Finally, some basic 3-level 8-PSK modulation codes using BCH codes as component codes are constructed and their coding gains are found for hard decision multistage decoding.

  1. A new code for the design and analysis of the heliostat field layout for power tower system

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

    Wei, Xiudong; Lu, Zhenwu; Yu, Weixing

    2010-04-15

    A new code for the design and analysis of the heliostat field layout for power tower system is developed. In the new code, a new method for the heliostat field layout is proposed based on the edge ray principle of nonimaging optics. The heliostat field boundary is constrained by the tower height, the receiver tilt angle and size and the heliostat efficiency factor which is the product of the annual cosine efficiency and the annual atmospheric transmission efficiency. With the new method, the heliostat can be placed with a higher efficiency and a faster response speed of the design andmore » optimization can be obtained. A new module for the analysis of the aspherical heliostat is created in the new code. A new toroidal heliostat field is designed and analyzed by using the new code. Compared with the spherical heliostat, the solar image radius of the field is reduced by about 30% by using the toroidal heliostat if the mirror shape and the tracking are ideal. In addition, to maximize the utilization of land, suitable crops can be considered to be planted under heliostats. To evaluate the feasibility of the crop growth, a method for calculating the annual distribution of sunshine duration on the land surface is developed as well. (author)« less

  2. Accumulate-Repeat-Accumulate-Accumulate Codes

    NASA Technical Reports Server (NTRS)

    Divsalar, Dariush; Dolinar, Samuel; Thorpe, Jeremy

    2007-01-01

    Accumulate-repeat-accumulate-accumulate (ARAA) codes have been proposed, inspired by the recently proposed accumulate-repeat-accumulate (ARA) codes. These are error-correcting codes suitable for use in a variety of wireless data-communication systems that include noisy channels. ARAA codes can be regarded as serial turbolike codes or as a subclass of low-density parity-check (LDPC) codes, and, like ARA codes they have projected graph or protograph representations; these characteristics make it possible to design high-speed iterative decoders that utilize belief-propagation algorithms. The objective in proposing ARAA codes as a subclass of ARA codes was to enhance the error-floor performance of ARA codes while maintaining simple encoding structures and low maximum variable node degree.

  3. The power induced effects module: A FORTRAN code which estimates lift increments due to power induced effects for V/STOL flight

    NASA Technical Reports Server (NTRS)

    Sandlin, Doral R.; Howard, Kipp E.

    1991-01-01

    A user friendly FORTRAN code that can be used for preliminary design of V/STOL aircraft is described. The program estimates lift increments, due to power induced effects, encountered by aircraft in V/STOL flight. These lift increments are calculated using empirical relations developed from wind tunnel tests and are due to suckdown, fountain, ground vortex, jet wake, and the reaction control system. The code can be used as a preliminary design tool along with NASA Ames' Aircraft Synthesis design code or as a stand-alone program for V/STOL aircraft designers. The Power Induced Effects (PIE) module was validated using experimental data and data computed from lift increment routines. Results are presented for many flat plate models along with the McDonnell Aircraft Company's MFVT (mixed flow vectored thrust) V/STOL preliminary design and a 15 percent scale model of the YAV-8B Harrier V/STOL aircraft. Trends and magnitudes of lift increments versus aircraft height above the ground were predicted well by the PIE module. The code also provided good predictions of the magnitudes of lift increments versus aircraft forward velocity. More experimental results are needed to determine how well the code predicts lift increments as they vary with jet deflection angle and angle of attack. The FORTRAN code is provided in the appendix.

  4. Automating the design of scientific computing software

    NASA Technical Reports Server (NTRS)

    Kant, Elaine

    1992-01-01

    SINAPSE is a domain-specific software design system that generates code from specifications of equations and algorithm methods. This paper describes the system's design techniques (planning in a space of knowledge-based refinement and optimization rules), user interaction style (user has option to control decision making), and representation of knowledge (rules and objects). It also summarizes how the system knowledge has evolved over time and suggests some issues in building software design systems to facilitate reuse.

  5. An Object-oriented Computer Code for Aircraft Engine Weight Estimation

    NASA Technical Reports Server (NTRS)

    Tong, Michael T.; Naylor, Bret A.

    2008-01-01

    Reliable engine-weight estimation at the conceptual design stage is critical to the development of new aircraft engines. It helps to identify the best engine concept amongst several candidates. At NASA Glenn (GRC), the Weight Analysis of Turbine Engines (WATE) computer code, originally developed by Boeing Aircraft, has been used to estimate the engine weight of various conceptual engine designs. The code, written in FORTRAN, was originally developed for NASA in 1979. Since then, substantial improvements have been made to the code to improve the weight calculations for most of the engine components. Most recently, to improve the maintainability and extensibility of WATE, the FORTRAN code has been converted into an object-oriented version. The conversion was done within the NASA s NPSS (Numerical Propulsion System Simulation) framework. This enables WATE to interact seamlessly with the thermodynamic cycle model which provides component flow data such as airflows, temperatures, and pressures, etc. that are required for sizing the components and weight calculations. The tighter integration between the NPSS and WATE would greatly enhance system-level analysis and optimization capabilities. It also would facilitate the enhancement of the WATE code for next-generation aircraft and space propulsion systems. In this paper, the architecture of the object-oriented WATE code (or WATE++) is described. Both the FORTRAN and object-oriented versions of the code are employed to compute the dimensions and weight of a 300- passenger aircraft engine (GE90 class). Both versions of the code produce essentially identical results as should be the case. Keywords: NASA, aircraft engine, weight, object-oriented

  6. Energy Storage System Safety: Plan Review and Inspection Checklist

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

    Cole, Pam C.; Conover, David R.

    Codes, standards, and regulations (CSR) governing the design, construction, installation, commissioning, and operation of the built environment are intended to protect the public health, safety, and welfare. While these documents change over time to address new technology and new safety challenges, there is generally some lag time between the introduction of a technology into the market and the time it is specifically covered in model codes and standards developed in the voluntary sector. After their development, there is also a timeframe of at least a year or two until the codes and standards are adopted. Until existing model codes andmore » standards are updated or new ones are developed and then adopted, one seeking to deploy energy storage technologies or needing to verify the safety of an installation may be challenged in trying to apply currently implemented CSRs to an energy storage system (ESS). The Energy Storage System Guide for Compliance with Safety Codes and Standards1 (CG), developed in June 2016, is intended to help address the acceptability of the design and construction of stationary ESSs, their component parts, and the siting, installation, commissioning, operations, maintenance, and repair/renovation of ESS within the built environment.« less

  7. Digital television system design study

    NASA Technical Reports Server (NTRS)

    Huth, G. K.

    1976-01-01

    The use of digital techniques for transmission of pictorial data is discussed for multi-frame images (television). Video signals are processed in a manner which includes quantization and coding such that they are separable from the noise introduced into the channel. The performance of digital television systems is determined by the nature of the processing techniques (i.e., whether the video signal itself or, instead, something related to the video signal is quantized and coded) and to the quantization and coding schemes employed.

  8. QR codes: next level of social media.

    PubMed

    Gottesman, Wesley; Baum, Neil

    2013-01-01

    The OR code, which is short for quick response code, system was invented in Japan for the auto industry. Its purpose was to track vehicles during manufacture; it was designed to allow high-speed component scanning. Now the scanning can be easily accomplished via cell phone, making the technology useful and within reach of your patients. There are numerous applications for OR codes in the contemporary medical practice. This article describes QR codes and how they might be applied for marketing and practice management.

  9. ICAN: A versatile code for predicting composite properties

    NASA Technical Reports Server (NTRS)

    Ginty, C. A.; Chamis, C. C.

    1986-01-01

    The Integrated Composites ANalyzer (ICAN), a stand-alone computer code, incorporates micromechanics equations and laminate theory to analyze/design multilayered fiber composite structures. Procedures for both the implementation of new data in ICAN and the selection of appropriate measured data are summarized for: (1) composite systems subject to severe thermal environments; (2) woven fabric/cloth composites; and (3) the selection of new composite systems including those made from high strain-to-fracture fibers. The comparisons demonstrate the versatility of ICAN as a reliable method for determining composite properties suitable for preliminary design.

  10. Transoptr — A second order beam transport design code with optimization and constraints

    NASA Astrophysics Data System (ADS)

    Heighway, E. A.; Hutcheon, R. M.

    1981-08-01

    This code was written initially to design an achromatic and isochronous reflecting magnet and has been extended to compete in capability (for constrained problems) with TRANSPORT. Its advantage is its flexibility in that the user writes a routine to describe his transport system. The routine allows the definition of general variables from which the system parameters can be derived. Further, the user can write any constraints he requires as algebraic equations relating the parameters. All variables may be used in either a first or second order optimization.

  11. Secure web-based invocation of large-scale plasma simulation codes

    NASA Astrophysics Data System (ADS)

    Dimitrov, D. A.; Busby, R.; Exby, J.; Bruhwiler, D. L.; Cary, J. R.

    2004-12-01

    We present our design and initial implementation of a web-based system for running, both in parallel and serial, Particle-In-Cell (PIC) codes for plasma simulations with automatic post processing and generation of visual diagnostics.

  12. Development of a Pebble-Bed Liquid-Nitrogen Evaporator/Superheater for the BRL 1/6th Scale Large Blast/Thermal Simulator Test Bed. Phase 1. Prototype Design and Analysis

    DTIC Science & Technology

    1991-08-01

    specifications are taken primarily from the 1983 version of the ASME Boiler and Pressure Vessel Code . Other design requirements were developea from standard safe...rules and practices of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code to provide a safe and reliable system

  13. 110 °C range athermalization of wavefront coding infrared imaging systems

    NASA Astrophysics Data System (ADS)

    Feng, Bin; Shi, Zelin; Chang, Zheng; Liu, Haizheng; Zhao, Yaohong

    2017-09-01

    110 °C range athermalization is significant but difficult for designing infrared imaging systems. Our wavefront coding athermalized infrared imaging system adopts an optical phase mask with less manufacturing errors and a decoding method based on shrinkage function. The qualitative experiments prove that our wavefront coding athermalized infrared imaging system has three prominent merits: (1) working well over a temperature range of 110 °C; (2) extending the focal depth up to 15.2 times; (3) achieving a decoded image being approximate to its corresponding in-focus infrared image, with a mean structural similarity index (MSSIM) value greater than 0.85.

  14. Evaluation of CFETR as a Fusion Nuclear Science Facility using multiple system codes

    NASA Astrophysics Data System (ADS)

    Chan, V. S.; Costley, A. E.; Wan, B. N.; Garofalo, A. M.; Leuer, J. A.

    2015-02-01

    This paper presents the results of a multi-system codes benchmarking study of the recently published China Fusion Engineering Test Reactor (CFETR) pre-conceptual design (Wan et al 2014 IEEE Trans. Plasma Sci. 42 495). Two system codes, General Atomics System Code (GASC) and Tokamak Energy System Code (TESC), using different methodologies to arrive at CFETR performance parameters under the same CFETR constraints show that the correlation between the physics performance and the fusion performance is consistent, and the computed parameters are in good agreement. Optimization of the first wall surface for tritium breeding and the minimization of the machine size are highly compatible. Variations of the plasma currents and profiles lead to changes in the required normalized physics performance, however, they do not significantly affect the optimized size of the machine. GASC and TESC have also been used to explore a lower aspect ratio, larger volume plasma taking advantage of the engineering flexibility in the CFETR design. Assuming the ITER steady-state scenario physics, the larger plasma together with a moderately higher BT and Ip can result in a high gain Qfus ˜ 12, Pfus ˜ 1 GW machine approaching DEMO-like performance. It is concluded that the CFETR baseline mode can meet the minimum goal of the Fusion Nuclear Science Facility (FNSF) mission and advanced physics will enable it to address comprehensively the outstanding critical technology gaps on the path to a demonstration reactor (DEMO). Before proceeding with CFETR construction steady-state operation has to be demonstrated, further development is needed to solve the divertor heat load issue, and blankets have to be designed with tritium breeding ratio (TBR) >1 as a target.

  15. A good performance watermarking LDPC code used in high-speed optical fiber communication system

    NASA Astrophysics Data System (ADS)

    Zhang, Wenbo; Li, Chao; Zhang, Xiaoguang; Xi, Lixia; Tang, Xianfeng; He, Wenxue

    2015-07-01

    A watermarking LDPC code, which is a strategy designed to improve the performance of the traditional LDPC code, was introduced. By inserting some pre-defined watermarking bits into original LDPC code, we can obtain a more correct estimation about the noise level in the fiber channel. Then we use them to modify the probability distribution function (PDF) used in the initial process of belief propagation (BP) decoding algorithm. This algorithm was tested in a 128 Gb/s PDM-DQPSK optical communication system and results showed that the watermarking LDPC code had a better tolerances to polarization mode dispersion (PMD) and nonlinearity than that of traditional LDPC code. Also, by losing about 2.4% of redundancy for watermarking bits, the decoding efficiency of the watermarking LDPC code is about twice of the traditional one.

  16. Screamer version 4.1

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

    Spielman, Rick; Struve, Kenneth W.; Kiefer, Mark L.

    2017-02-16

    Screamer is a special purpose circuit code developed for the design of Pulsed Power systems. It models electrical circuits which have a restricted topology in order to provide a fast-running tool while still allowing configurations general enough for most Pulsed Power system designs

  17. A Monte Carlo model system for core analysis and epithermal neutron beam design at the Washington State University Radiation Center

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

    Burns, T.D. Jr.

    1996-05-01

    The Monte Carlo Model System (MCMS) for the Washington State University (WSU) Radiation Center provides a means through which core criticality and power distributions can be calculated, as well as providing a method for neutron and photon transport necessary for BNCT epithermal neutron beam design. The computational code used in this Model System is MCNP4A. The geometric capability of this Monte Carlo code allows the WSU system to be modeled very accurately. A working knowledge of the MCNP4A neutron transport code increases the flexibility of the Model System and is recommended, however, the eigenvalue/power density problems can be run withmore » little direct knowledge of MCNP4A. Neutron and photon particle transport require more experience with the MCNP4A code. The Model System consists of two coupled subsystems; the Core Analysis and Source Plane Generator Model (CASP), and the BeamPort Shell Particle Transport Model (BSPT). The CASP Model incorporates the S({alpha}, {beta}) thermal treatment, and is run as a criticality problem yielding, the system eigenvalue (k{sub eff}), the core power distribution, and an implicit surface source for subsequent particle transport in the BSPT Model. The BSPT Model uses the source plane generated by a CASP run to transport particles through the thermal column beamport. The user can create filter arrangements in the beamport and then calculate characteristics necessary for assessing the BNCT potential of the given filter want. Examples of the characteristics to be calculated are: neutron fluxes, neutron currents, fast neutron KERMAs and gamma KERMAs. The MCMS is a useful tool for the WSU system. Those unfamiliar with the MCNP4A code can use the MCMS transparently for core analysis, while more experienced users will find the particle transport capabilities very powerful for BNCT filter design.« less

  18. Use of the MATRIXx Integrated Toolkit on the Microwave Anisotropy Probe Attitude Control System

    NASA Technical Reports Server (NTRS)

    Ward, David K.; Andrews, Stephen F.; McComas, David C.; ODonnell, James R., Jr.

    1999-01-01

    Recent advances in analytical software tools allow the analysis, simulation, flight code, and documentation of an algorithm to be generated from a single source, all within one integrated analytical design package. NASA's Microwave Anisotropy Probe project has used one such package, Integrated Systems' MATRIXx suite, in the design of the spacecraft's Attitude Control System. The project's experience with the linear analysis, simulation, code generation, and documentation tools will be presented and compared with more traditional development tools. In particular, the quality of the flight software generated will be examined in detail. Finally, lessons learned on each of the tools will be shared.

  19. VLSI design of lossless frame recompression using multi-orientation prediction

    NASA Astrophysics Data System (ADS)

    Lee, Yu-Hsuan; You, Yi-Lun; Chen, Yi-Guo

    2016-01-01

    Pursuing an experience of high-end visual quality drives human to demand a higher display resolution and a higher frame rate. Hence, a lot of powerful coding tools are aggregated together in emerging video coding standards to improve coding efficiency. This also makes video coding standards suffer from two design challenges: heavy computation and tremendous memory bandwidth. The first issue can be properly solved by a careful hardware architecture design with advanced semiconductor processes. Nevertheless, the second one becomes a critical design bottleneck for a modern video coding system. In this article, a lossless frame recompression using multi-orientation prediction technique is proposed to overcome this bottleneck. This work is realised into a silicon chip with the technology of TSMC 0.18 µm CMOS process. Its encoding capability can reach full-HD (1920 × 1080)@48 fps. The chip power consumption is 17.31 mW@100 MHz. Core area and chip area are 0.83 × 0.83 mm2 and 1.20 × 1.20 mm2, respectively. Experiment results demonstrate that this work exhibits an outstanding performance on lossless compression ratio with a competitive hardware performance.

  20. Expert system for maintenance management of a boiling water reactor power plant

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

    Hong Shen; Liou, L.W.; Levine, S.

    1992-01-01

    An expert system code has been developed for the maintenance of two boiling water reactor units in Berwick, Pennsylvania, that are operated by the Pennsylvania Power and Light Company (PP and L). The objective of this expert system code, where the knowledge of experienced operators and engineers is captured and implemented, is to support the decisions regarding which components can be safely and reliably removed from service for maintenance. It can also serve as a query-answering facility for checking the plant system status and for training purposes. The operating and maintenance information of a large number of support systems, whichmore » must be available for emergencies and/or in the event of an accident, is stored in the data base of the code. It identifies the relevant technical specifications and management rules for shutting down any one of the systems or removing a component from service to support maintenance. Because of the complexity and time needed to incorporate a large number of systems and their components, the first phase of the expert system develops a prototype code, which includes only the reactor core isolation coolant system, the high-pressure core injection system, the instrument air system, the service water system, and the plant electrical system. The next phase is scheduled to expand the code to include all other systems. This paper summarizes the prototype code and the design concept of the complete expert system code for maintenance management of all plant systems and components.« less

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

    NASA Technical Reports Server (NTRS)

    Erickson, W. J. (Editor)

    1979-01-01

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

  2. Run-length encoding graphic rules, biochemically editable designs and steganographical numeric data embedment for DNA-based cryptographical coding system

    PubMed Central

    Kawano, Tomonori

    2013-01-01

    There have been a wide variety of approaches for handling the pieces of DNA as the “unplugged” tools for digital information storage and processing, including a series of studies applied to the security-related area, such as DNA-based digital barcodes, water marks and cryptography. In the present article, novel designs of artificial genes as the media for storing the digitally compressed data for images are proposed for bio-computing purpose while natural genes principally encode for proteins. Furthermore, the proposed system allows cryptographical application of DNA through biochemically editable designs with capacity for steganographical numeric data embedment. As a model case of image-coding DNA technique application, numerically and biochemically combined protocols are employed for ciphering the given “passwords” and/or secret numbers using DNA sequences. The “passwords” of interest were decomposed into single letters and translated into the font image coded on the separate DNA chains with both the coding regions in which the images are encoded based on the novel run-length encoding rule, and the non-coding regions designed for biochemical editing and the remodeling processes revealing the hidden orientation of letters composing the original “passwords.” The latter processes require the molecular biological tools for digestion and ligation of the fragmented DNA molecules targeting at the polymerase chain reaction-engineered termini of the chains. Lastly, additional protocols for steganographical overwriting of the numeric data of interests over the image-coding DNA are also discussed. PMID:23750303

  3. A Strategy for Reusing the Data of Electronic Medical Record Systems for Clinical Research.

    PubMed

    Matsumura, Yasushi; Hattori, Atsushi; Manabe, Shiro; Tsuda, Tsutomu; Takeda, Toshihiro; Okada, Katsuki; Murata, Taizo; Mihara, Naoki

    2016-01-01

    There is a great need to reuse data stored in electronic medical records (EMR) databases for clinical research. We previously reported the development of a system in which progress notes and case report forms (CRFs) were simultaneously recorded using a template in the EMR in order to exclude redundant data entry. To make the data collection process more efficient, we are developing a system in which the data originally stored in the EMR database can be populated within a frame in a template. We developed interface plugin modules that retrieve data from the databases of other EMR applications. A universal keyword written in a template master is converted to a local code using a data conversion table, then the objective data is retrieved from the corresponding database. The template element data, which are entered by a template, are stored in the template element database. To retrieve the data entered by other templates, the objective data is designated by the template element code with the template code, or by the concept code if it is written for the element. When the application systems in the EMR generate documents, they also generate a PDF file and a corresponding document profile XML, which includes important data, and send them to the document archive server and the data sharing saver, respectively. In the data sharing server, the data are represented by an item with an item code with a document class code and its value. By linking a concept code to an item identifier, an objective data can be retrieved by designating a concept code. We employed a flexible strategy in which a unique identifier for a hospital is initially attached to all of the data that the hospital generates. The identifier is secondarily linked with concept codes. The data that are not linked with a concept code can also be retrieved using the unique identifier of the hospital. This strategy makes it possible to reuse any of a hospital's data.

  4. Turbopump Design and Analysis Approach for Nuclear Thermal Rockets

    NASA Technical Reports Server (NTRS)

    Chen, Shu-cheng S.; Veres, Joseph P.; Fittje, James E.

    2006-01-01

    A rocket propulsion system, whether it is a chemical rocket or a nuclear thermal rocket, is fairly complex in detail but rather simple in principle. Among all the interacting parts, three components stand out: they are pumps and turbines (turbopumps), and the thrust chamber. To obtain an understanding of the overall rocket propulsion system characteristics, one starts from analyzing the interactions among these three components. It is therefore of utmost importance to be able to satisfactorily characterize the turbopump, level by level, at all phases of a vehicle design cycle. Here at NASA Glenn Research Center, as the starting phase of a rocket engine design, specifically a Nuclear Thermal Rocket Engine design, we adopted the approach of using a high level system cycle analysis code (NESS) to obtain an initial analysis of the operational characteristics of a turbopump required in the propulsion system. A set of turbopump design codes (PumpDes and TurbDes) were then executed to obtain sizing and performance characteristics of the turbopump that were consistent with the mission requirements. A set of turbopump analyses codes (PUMPA and TURBA) were applied to obtain the full performance map for each of the turbopump components; a two dimensional layout of the turbopump based on these mean line analyses was also generated. Adequacy of the turbopump conceptual design will later be determined by further analyses and evaluation. In this paper, descriptions and discussions of the aforementioned approach are provided and future outlooks are discussed.

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

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

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

  6. Numerical, analytical, experimental study of fluid dynamic forces in seals

    NASA Technical Reports Server (NTRS)

    Shapiro, William; Artiles, Antonio; Aggarwal, Bharat; Walowit, Jed; Athavale, Mahesh M.; Preskwas, Andrzej J.

    1992-01-01

    NASA/Lewis Research Center is sponsoring a program for providing computer codes for analyzing and designing turbomachinery seals for future aerospace and engine systems. The program is made up of three principal components: (1) the development of advanced three dimensional (3-D) computational fluid dynamics codes, (2) the production of simpler two dimensional (2-D) industrial codes, and (3) the development of a knowledge based system (KBS) that contains an expert system to assist in seal selection and design. The first task has been to concentrate on cylindrical geometries with straight, tapered, and stepped bores. Improvements have been made by adoption of a colocated grid formulation, incorporation of higher order, time accurate schemes for transient analysis and high order discretization schemes for spatial derivatives. This report describes the mathematical formulations and presents a variety of 2-D results, including labyrinth and brush seal flows. Extensions of 3-D are presently in progress.

  7. Design of an integrated airframe/propulsion control system architecture

    NASA Technical Reports Server (NTRS)

    Cohen, Gerald C.; Lee, C. William; Strickland, Michael J.

    1990-01-01

    The design of an integrated airframe/propulsion control system architecture is described. The design is based on a prevalidation methodology that used both reliability and performance tools. An account is given of the motivation for the final design and problems associated with both reliability and performance modeling. The appendices contain a listing of the code for both the reliability and performance model used in the design.

  8. Pulse Code Modulation (PCM) encoder handbook for Aydin Vector MMP-900 series system

    NASA Technical Reports Server (NTRS)

    Raphael, David

    1995-01-01

    This handbook explicates the hardware and software properties of a time division multiplex system. This system is used to sample analog and digital data. The data is then merged with frame synchronization information to produce a serial pulse coded modulation (PCM) bit stream. Information in this handbook is required by users to design congruous interface and attest effective utilization of this encoder system. Aydin Vector provides all of the components for these systems to Goddard Space Flight Center/Wallops Flight Facility.

  9. Advances in Engineering Software for Lift Transportation Systems

    NASA Astrophysics Data System (ADS)

    Kazakoff, Alexander Borisoff

    2012-03-01

    In this paper an attempt is performed at computer modelling of ropeway ski lift systems. The logic in these systems is based on a travel form between the two terminals, which operates with high capacity cabins, chairs, gondolas or draw-bars. Computer codes AUTOCAD, MATLAB and Compaq-Visual Fortran - version 6.6 are used in the computer modelling. The rope systems computer modelling is organized in two stages in this paper. The first stage is organization of the ground relief profile and a design of the lift system as a whole, according to the terrain profile and the climatic and atmospheric conditions. The ground profile is prepared by the geodesists and is presented in an AUTOCAD view. The next step is the design of the lift itself which is performed by programmes using the computer code MATLAB. The second stage of the computer modelling is performed after the optimization of the co-ordinates and the lift profile using the computer code MATLAB. Then the co-ordinates and the parameters are inserted into a program written in Compaq Visual Fortran - version 6.6., which calculates 171 lift parameters, organized in 42 tables. The objective of the work presented in this paper is an attempt at computer modelling of the design and parameters derivation of the rope way systems and their computer variation and optimization.

  10. A neutron spectrum unfolding computer code based on artificial neural networks

    NASA Astrophysics Data System (ADS)

    Ortiz-Rodríguez, J. M.; Reyes Alfaro, A.; Reyes Haro, A.; Cervantes Viramontes, J. M.; Vega-Carrillo, H. R.

    2014-02-01

    The Bonner Spheres Spectrometer consists of a thermal neutron sensor placed at the center of a number of moderating polyethylene spheres of different diameters. From the measured readings, information can be derived about the spectrum of the neutron field where measurements were made. Disadvantages of the Bonner system are the weight associated with each sphere and the need to sequentially irradiate the spheres, requiring long exposure periods. Provided a well-established response matrix and adequate irradiation conditions, the most delicate part of neutron spectrometry, is the unfolding process. The derivation of the spectral information is not simple because the unknown is not given directly as a result of the measurements. The drawbacks associated with traditional unfolding procedures have motivated the need of complementary approaches. Novel methods based on Artificial Intelligence, mainly Artificial Neural Networks, have been widely investigated. In this work, a neutron spectrum unfolding code based on neural nets technology is presented. This code is called Neutron Spectrometry and Dosimetry with Artificial Neural networks unfolding code that was designed in a graphical interface. The core of the code is an embedded neural network architecture previously optimized using the robust design of artificial neural networks methodology. The main features of the code are: easy to use, friendly and intuitive to the user. This code was designed for a Bonner Sphere System based on a 6LiI(Eu) neutron detector and a response matrix expressed in 60 energy bins taken from an International Atomic Energy Agency compilation. The main feature of the code is that as entrance data, for unfolding the neutron spectrum, only seven rate counts measured with seven Bonner spheres are required; simultaneously the code calculates 15 dosimetric quantities as well as the total flux for radiation protection purposes. This code generates a full report with all information of the unfolding in the HTML format. NSDann unfolding code is freely available, upon request to the authors.

  11. Quasi 1D Modeling of Mixed Compression Supersonic Inlets

    NASA Technical Reports Server (NTRS)

    Kopasakis, George; Connolly, Joseph W.; Paxson, Daniel E.; Woolwine, Kyle J.

    2012-01-01

    The AeroServoElasticity task under the NASA Supersonics Project is developing dynamic models of the propulsion system and the vehicle in order to conduct research for integrated vehicle dynamic performance. As part of this effort, a nonlinear quasi 1-dimensional model of the 2-dimensional bifurcated mixed compression supersonic inlet is being developed. The model utilizes computational fluid dynamics for both the supersonic and subsonic diffusers. The oblique shocks are modeled utilizing compressible flow equations. This model also implements variable geometry required to control the normal shock position. The model is flexible and can also be utilized to simulate other mixed compression supersonic inlet designs. The model was validated both in time and in the frequency domain against the legacy LArge Perturbation INlet code, which has been previously verified using test data. This legacy code written in FORTRAN is quite extensive and complex in terms of the amount of software and number of subroutines. Further, the legacy code is not suitable for closed loop feedback controls design, and the simulation environment is not amenable to systems integration. Therefore, a solution is to develop an innovative, more simplified, mixed compression inlet model with the same steady state and dynamic performance as the legacy code that also can be used for controls design. The new nonlinear dynamic model is implemented in MATLAB Simulink. This environment allows easier development of linear models for controls design for shock positioning. The new model is also well suited for integration with a propulsion system model to study inlet/propulsion system performance, and integration with an aero-servo-elastic system model to study integrated vehicle ride quality, vehicle stability, and efficiency.

  12. Space Shuttle Debris Impact Tool Assessment Using the Modern Design of Experiments

    NASA Technical Reports Server (NTRS)

    DeLoach, Richard; Rayos, Elonsio M.; Campbell, Charles H.; Rickman, Steven L.; Larsen, Curtis E.

    2007-01-01

    Complex computer codes are used to estimate thermal and structural reentry loads on the Shuttle Orbiter induced by ice and foam debris impact during ascent. Such debris can create cavities in the Shuttle Thermal Protection System. The sizes and shapes of these cavities are approximated to accommodate a code limitation that requires simple "shoebox" geometries to describe the cavities -- rectangular areas and planar walls that are at constant angles with respect to vertical. These approximations induce uncertainty in the code results. The Modern Design of Experiments (MDOE) has recently been applied to develop a series of resource-minimal computational experiments designed to generate low-order polynomial graduating functions to approximate the more complex underlying codes. These polynomial functions were then used to propagate cavity geometry errors to estimate the uncertainty they induce in the reentry load calculations performed by the underlying code. This paper describes a methodological study focused on evaluating the application of MDOE to future operational codes in a rapid and low-cost way to assess the effects of cavity geometry uncertainty.

  13. Reed Solomon codes for error control in byte organized computer memory systems

    NASA Technical Reports Server (NTRS)

    Lin, S.; Costello, D. J., Jr.

    1984-01-01

    A problem in designing semiconductor memories is to provide some measure of error control without requiring excessive coding overhead or decoding time. In LSI and VLSI technology, memories are often organized on a multiple bit (or byte) per chip basis. For example, some 256K-bit DRAM's are organized in 32Kx8 bit-bytes. Byte oriented codes such as Reed Solomon (RS) codes can provide efficient low overhead error control for such memories. However, the standard iterative algorithm for decoding RS codes is too slow for these applications. Some special decoding techniques for extended single-and-double-error-correcting RS codes which are capable of high speed operation are presented. These techniques are designed to find the error locations and the error values directly from the syndrome without having to use the iterative algorithm to find the error locator polynomial.

  14. BOCA BASIC BUILDING CODE. 4TH ED., 1965 AND 1967. BOCA BASIC BUILDING CODE ACCUMULATIVE SUPPLEMENT.

    ERIC Educational Resources Information Center

    Building Officials Conference of America, Inc., Chicago, IL.

    NATIONALLY RECOGNIZED STANDARDS FOR THE EVALUATION OF MINIMUM SAFE PRACTICE OR FOR DETERMINING THE PERFORMANCE OF MATERIALS OR SYSTEMS OF CONSTRUCTION HAVE BEEN COMPILED AS AN AID TO DESIGNERS AND LOCAL OFFICIALS. THE CODE PRESENTS REGULATIONS IN TERMS OF MEASURED PERFORMANCE RATHER THAN IN RIGID SPECIFICATION OF MATERIALS OR METHODS. THE AREAS…

  15. Huffman coding in advanced audio coding standard

    NASA Astrophysics Data System (ADS)

    Brzuchalski, Grzegorz

    2012-05-01

    This article presents several hardware architectures of Advanced Audio Coding (AAC) Huffman noiseless encoder, its optimisations and working implementation. Much attention has been paid to optimise the demand of hardware resources especially memory size. The aim of design was to get as short binary stream as possible in this standard. The Huffman encoder with whole audio-video system has been implemented in FPGA devices.

  16. 77 FR 37471 - National Automotive Sampling System

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-21

    ... a comprehensive review of the National Automotive Sampling System (NASS) research design and data... comment on the current data elements, propose new data elements, make suggestions on the research design... should consider to improve crash data. Current NASS data elements, coding instructions, and descriptive...

  17. Self-assembled software and method of overriding software execution

    DOEpatents

    Bouchard, Ann M.; Osbourn, Gordon C.

    2013-01-08

    A computer-implemented software self-assembled system and method for providing an external override and monitoring capability to dynamically self-assembling software containing machines that self-assemble execution sequences and data structures. The method provides an external override machine that can be introduced into a system of self-assembling machines while the machines are executing such that the functionality of the executing software can be changed or paused without stopping the code execution and modifying the existing code. Additionally, a monitoring machine can be introduced without stopping code execution that can monitor specified code execution functions by designated machines and communicate the status to an output device.

  18. Image sensor system with bio-inspired efficient coding and adaptation.

    PubMed

    Okuno, Hirotsugu; Yagi, Tetsuya

    2012-08-01

    We designed and implemented an image sensor system equipped with three bio-inspired coding and adaptation strategies: logarithmic transform, local average subtraction, and feedback gain control. The system comprises a field-programmable gate array (FPGA), a resistive network, and active pixel sensors (APS), whose light intensity-voltage characteristics are controllable. The system employs multiple time-varying reset voltage signals for APS in order to realize multiple logarithmic intensity-voltage characteristics, which are controlled so that the entropy of the output image is maximized. The system also employs local average subtraction and gain control in order to obtain images with an appropriate contrast. The local average is calculated by the resistive network instantaneously. The designed system was successfully used to obtain appropriate images of objects that were subjected to large changes in illumination.

  19. Increasing Flexibility in Energy Code Compliance: Performance Packages

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

    Hart, Philip R.; Rosenberg, Michael I.

    Energy codes and standards have provided significant increases in building efficiency over the last 38 years, since the first national energy code was published in late 1975. The most commonly used path in energy codes, the prescriptive path, appears to be reaching a point of diminishing returns. As the code matures, the prescriptive path becomes more complicated, and also more restrictive. It is likely that an approach that considers the building as an integrated system will be necessary to achieve the next real gains in building efficiency. Performance code paths are increasing in popularity; however, there remains a significant designmore » team overhead in following the performance path, especially for smaller buildings. This paper focuses on development of one alternative format, prescriptive packages. A method to develop building-specific prescriptive packages is reviewed based on a multiple runs of prototypical building models that are used to develop parametric decision analysis to determines a set of packages with equivalent energy performance. The approach is designed to be cost-effective and flexible for the design team while achieving a desired level of energy efficiency performance. A demonstration of the approach based on mid-sized office buildings with two HVAC system types is shown along with a discussion of potential applicability in the energy code process.« less

  20. A user's manual for DELSOL3: A computer code for calculating the optical performance and optimal system design for solar thermal central receiver plants

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

    Kistler, B.L.

    DELSOL3 is a revised and updated version of the DELSOL2 computer program (SAND81-8237) for calculating collector field performance and layout and optimal system design for solar thermal central receiver plants. The code consists of a detailed model of the optical performance, a simpler model of the non-optical performance, an algorithm for field layout, and a searching algorithm to find the best system design based on energy cost. The latter two features are coupled to a cost model of central receiver components and an economic model for calculating energy costs. The code can handle flat, focused and/or canted heliostats, and externalmore » cylindrical, multi-aperture cavity, and flat plate receivers. The program optimizes the tower height, receiver size, field layout, heliostat spacings, and tower position at user specified power levels subject to flux limits on the receiver and land constraints for field layout. DELSOL3 maintains the advantages of speed and accuracy which are characteristics of DELSOL2.« less

  1. Validation of a pair of computer codes for estimation and optimization of subsonic aerodynamic performance of simple hinged-flap systems for thin swept wings

    NASA Technical Reports Server (NTRS)

    Carlson, Harry W.; Darden, Christine M.

    1988-01-01

    Extensive correlations of computer code results with experimental data are employed to illustrate the use of linearized theory attached flow methods for the estimation and optimization of the aerodynamic performance of simple hinged flap systems. Use of attached flow methods is based on the premise that high levels of aerodynamic efficiency require a flow that is as nearly attached as circumstances permit. A variety of swept wing configurations are considered ranging from fighters to supersonic transports, all with leading- and trailing-edge flaps for enhancement of subsonic aerodynamic efficiency. The results indicate that linearized theory attached flow computer code methods provide a rational basis for the estimation and optimization of flap system aerodynamic performance at subsonic speeds. The analysis also indicates that vortex flap design is not an opposing approach but is closely related to attached flow design concepts. The successful vortex flap design actually suppresses the formation of detached vortices to produce a small vortex which is restricted almost entirely to the leading edge flap itself.

  2. Optimal block cosine transform image coding for noisy channels

    NASA Technical Reports Server (NTRS)

    Vaishampayan, V.; Farvardin, N.

    1986-01-01

    The two dimensional block transform coding scheme based on the discrete cosine transform was studied extensively for image coding applications. While this scheme has proven to be efficient in the absence of channel errors, its performance degrades rapidly over noisy channels. A method is presented for the joint source channel coding optimization of a scheme based on the 2-D block cosine transform when the output of the encoder is to be transmitted via a memoryless design of the quantizers used for encoding the transform coefficients. This algorithm produces a set of locally optimum quantizers and the corresponding binary code assignment for the assumed transform coefficient statistics. To determine the optimum bit assignment among the transform coefficients, an algorithm was used based on the steepest descent method, which under certain convexity conditions on the performance of the channel optimized quantizers, yields the optimal bit allocation. Comprehensive simulation results for the performance of this locally optimum system over noisy channels were obtained and appropriate comparisons against a reference system designed for no channel error were rendered.

  3. Unmanned Sea Surface Vehicle (USSV) Motion Data and Refueling Equipment Design

    DTIC Science & Technology

    2010-01-01

    knowledge of on-coming waves and craft controls system elements. The same information could be used to optimize structural design of USSV hull or host...Carderock Division, Detachment Norfolk Code 232- Systems Design &Integration Little Creek Amphibious Base 2600 Tarawa Court, Norfolk, VA. 23521-3239...and USSV speed. The resulting extensive set of motion and positional data will be useful for future system designers for years to come. This work

  4. Long term integrity for space station power systems

    NASA Technical Reports Server (NTRS)

    Leckie, F. A.; Marriott, D. L.

    1991-01-01

    A study was made of the High Temperature Design Codes ASME N47, British R5, and the French RCC-MR Rules. It is concluded that all these codes provide a good basis of design for space application. The new British R5 is the most complete since it deals with the problem of defects. The ASME N47 was subjected longer to practical application and scrutiny. A draft code is introduced, and a proposed draft for high temperature design in which attempts were made to identify gaps and improvements is suggested. The design is limited by creep characteristics. In these circumstances, life is strongly affected by the selected value of the factor of safety. The factor of safety of primary loads adopted in the codes is 1.5. Maybe a lower value of 1.25 is permissible for use in space. Long term creep rupture data for HAYNES 188 is deficient and it is suggested that extrapolation methods be investigated.

  5. Cardinality enhancement utilizing Sequential Algorithm (SeQ) code in OCDMA system

    NASA Astrophysics Data System (ADS)

    Fazlina, C. A. S.; Rashidi, C. B. M.; Rahman, A. K.; Aljunid, S. A.

    2017-11-01

    Optical Code Division Multiple Access (OCDMA) has been important with increasing demand for high capacity and speed for communication in optical networks because of OCDMA technique high efficiency that can be achieved, hence fibre bandwidth is fully used. In this paper we will focus on Sequential Algorithm (SeQ) code with AND detection technique using Optisystem design tool. The result revealed SeQ code capable to eliminate Multiple Access Interference (MAI) and improve Bit Error Rate (BER), Phase Induced Intensity Noise (PIIN) and orthogonally between users in the system. From the results, SeQ shows good performance of BER and capable to accommodate 190 numbers of simultaneous users contrast with existing code. Thus, SeQ code have enhanced the system about 36% and 111% of FCC and DCS code. In addition, SeQ have good BER performance 10-25 at 155 Mbps in comparison with 622 Mbps, 1 Gbps and 2 Gbps bit rate. From the plot graph, 155 Mbps bit rate is suitable enough speed for FTTH and LAN networks. Resolution can be made based on the superior performance of SeQ code. Thus, these codes will give an opportunity in OCDMA system for better quality of service in an optical access network for future generation's usage

  6. Fast QC-LDPC code for free space optical communication

    NASA Astrophysics Data System (ADS)

    Wang, Jin; Zhang, Qi; Udeh, Chinonso Paschal; Wu, Rangzhong

    2017-02-01

    Free Space Optical (FSO) Communication systems use the atmosphere as a propagation medium. Hence the atmospheric turbulence effects lead to multiplicative noise related with signal intensity. In order to suppress the signal fading induced by multiplicative noise, we propose a fast Quasi-Cyclic (QC) Low-Density Parity-Check (LDPC) code for FSO Communication systems. As a linear block code based on sparse matrix, the performances of QC-LDPC is extremely near to the Shannon limit. Currently, the studies on LDPC code in FSO Communications is mainly focused on Gauss-channel and Rayleigh-channel, respectively. In this study, the LDPC code design over atmospheric turbulence channel which is nether Gauss-channel nor Rayleigh-channel is closer to the practical situation. Based on the characteristics of atmospheric channel, which is modeled as logarithmic-normal distribution and K-distribution, we designed a special QC-LDPC code, and deduced the log-likelihood ratio (LLR). An irregular QC-LDPC code for fast coding, of which the rates are variable, is proposed in this paper. The proposed code achieves excellent performance of LDPC codes and can present the characteristics of high efficiency in low rate, stable in high rate and less number of iteration. The result of belief propagation (BP) decoding shows that the bit error rate (BER) obviously reduced as the Signal-to-Noise Ratio (SNR) increased. Therefore, the LDPC channel coding technology can effectively improve the performance of FSO. At the same time, the BER, after decoding reduces with the increase of SNR arbitrarily, and not having error limitation platform phenomenon with error rate slowing down.

  7. Structured Design Language for Computer Programs

    NASA Technical Reports Server (NTRS)

    Pace, Walter H., Jr.

    1986-01-01

    Box language used at all stages of program development. Developed to provide improved productivity in designing, coding, and maintaining computer programs. BOX system written in FORTRAN 77 for batch execution.

  8. Coded-aperture Compton camera for gamma-ray imaging

    NASA Astrophysics Data System (ADS)

    Farber, Aaron M.

    This dissertation describes the development of a novel gamma-ray imaging system concept and presents results from Monte Carlo simulations of the new design. Current designs for large field-of-view gamma cameras suitable for homeland security applications implement either a coded aperture or a Compton scattering geometry to image a gamma-ray source. Both of these systems require large, expensive position-sensitive detectors in order to work effectively. By combining characteristics of both of these systems, a new design can be implemented that does not require such expensive detectors and that can be scaled down to a portable size. This new system has significant promise in homeland security, astronomy, botany and other fields, while future iterations may prove useful in medical imaging, other biological sciences and other areas, such as non-destructive testing. A proof-of-principle study of the new gamma-ray imaging system has been performed by Monte Carlo simulation. Various reconstruction methods have been explored and compared. General-Purpose Graphics-Processor-Unit (GPGPU) computation has also been incorporated. The resulting code is a primary design tool for exploring variables such as detector spacing, material selection and thickness and pixel geometry. The advancement of the system from a simple 1-dimensional simulation to a full 3-dimensional model is described. Methods of image reconstruction are discussed and results of simulations consisting of both a 4 x 4 and a 16 x 16 object space mesh have been presented. A discussion of the limitations and potential areas of further study is also presented.

  9. Formal Validation of Fault Management Design Solutions

    NASA Technical Reports Server (NTRS)

    Gibson, Corrina; Karban, Robert; Andolfato, Luigi; Day, John

    2013-01-01

    The work presented in this paper describes an approach used to develop SysML modeling patterns to express the behavior of fault protection, test the model's logic by performing fault injection simulations, and verify the fault protection system's logical design via model checking. A representative example, using a subset of the fault protection design for the Soil Moisture Active-Passive (SMAP) system, was modeled with SysML State Machines and JavaScript as Action Language. The SysML model captures interactions between relevant system components and system behavior abstractions (mode managers, error monitors, fault protection engine, and devices/switches). Development of a method to implement verifiable and lightweight executable fault protection models enables future missions to have access to larger fault test domains and verifiable design patterns. A tool-chain to transform the SysML model to jpf-Statechart compliant Java code and then verify the generated code via model checking was established. Conclusions and lessons learned from this work are also described, as well as potential avenues for further research and development.

  10. TRAC-PF1 code verification with data from the OTIS test facility. [Once-Through Intergral System

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

    Childerson, M.T.; Fujita, R.K.

    1985-01-01

    A computer code (TRAC-PF1/MOD1) developed for predicting transient thermal and hydraulic integral nuclear steam supply system (NSSS) response was benchmarked. Post-small break loss-of-coolant accident (LOCA) data from a scaled, experimental facility, designated the One-Through Integral System (OTIS), were obtained for the Babcock and Wilcox NSSS and compared to TRAC predictions. The OTIS tests provided a challenging small break LOCA data set for TRAC verification. The major phases of a small break LOCA observed in the OTIS tests included pressurizer draining and loop saturation, intermittent reactor coolant system circulation, boiler-condenser mode, and the initial stages of refill. The TRAC code wasmore » successful in predicting OTIS loop conditions (system pressures and temperatures) after modification of the steam generator model. In particular, the code predicted both pool and auxiliary-feedwater initiated boiler-condenser mode heat transfer.« less

  11. Development of Tripropellant CFD Design Code

    NASA Technical Reports Server (NTRS)

    Farmer, Richard C.; Cheng, Gary C.; Anderson, Peter G.

    1998-01-01

    A tripropellant, such as GO2/H2/RP-1, CFD design code has been developed to predict the local mixing of multiple propellant streams as they are injected into a rocket motor. The code utilizes real fluid properties to account for the mixing and finite-rate combustion processes which occur near an injector faceplate, thus the analysis serves as a multi-phase homogeneous spray combustion model. Proper accounting of the combustion allows accurate gas-side temperature predictions which are essential for accurate wall heating analyses. The complex secondary flows which are predicted to occur near a faceplate cannot be quantitatively predicted by less accurate methodology. Test cases have been simulated to describe an axisymmetric tripropellant coaxial injector and a 3-dimensional RP-1/LO2 impinger injector system. The analysis has been shown to realistically describe such injector combustion flowfields. The code is also valuable to design meaningful future experiments by determining the critical location and type of measurements needed.

  12. National Combustion Code: Parallel Implementation and Performance

    NASA Technical Reports Server (NTRS)

    Quealy, A.; Ryder, R.; Norris, A.; Liu, N.-S.

    2000-01-01

    The National Combustion Code (NCC) is being developed by an industry-government team for the design and analysis of combustion systems. CORSAIR-CCD is the current baseline reacting flow solver for NCC. This is a parallel, unstructured grid code which uses a distributed memory, message passing model for its parallel implementation. The focus of the present effort has been to improve the performance of the NCC flow solver to meet combustor designer requirements for model accuracy and analysis turnaround time. Improving the performance of this code contributes significantly to the overall reduction in time and cost of the combustor design cycle. This paper describes the parallel implementation of the NCC flow solver and summarizes its current parallel performance on an SGI Origin 2000. Earlier parallel performance results on an IBM SP-2 are also included. The performance improvements which have enabled a turnaround of less than 15 hours for a 1.3 million element fully reacting combustion simulation are described.

  13. Overview: Applications of numerical optimization methods to helicopter design problems

    NASA Technical Reports Server (NTRS)

    Miura, H.

    1984-01-01

    There are a number of helicopter design problems that are well suited to applications of numerical design optimization techniques. Adequate implementation of this technology will provide high pay-offs. There are a number of numerical optimization programs available, and there are many excellent response/performance analysis programs developed or being developed. But integration of these programs in a form that is usable in the design phase should be recognized as important. It is also necessary to attract the attention of engineers engaged in the development of analysis capabilities and to make them aware that analysis capabilities are much more powerful if integrated into design oriented codes. Frequently, the shortcoming of analysis capabilities are revealed by coupling them with an optimization code. Most of the published work has addressed problems in preliminary system design, rotor system/blade design or airframe design. Very few published results were found in acoustics, aerodynamics and control system design. Currently major efforts are focused on vibration reduction, and aerodynamics/acoustics applications appear to be growing fast. The development of a computer program system to integrate the multiple disciplines required in helicopter design with numerical optimization technique is needed. Activities in Britain, Germany and Poland are identified, but no published results from France, Italy, the USSR or Japan were found.

  14. Pulse Code Modulation (PCM) encoder handbook for Aydin Vector MMP-600 series system

    NASA Technical Reports Server (NTRS)

    Currier, S. F.; Powell, W. R.

    1986-01-01

    The hardware and software characteristics of a time division multiplex system are described. The system is used to sample analog and digital data. The data is merged with synchronization information to produce a serial pulse coded modulation (PCM) bit stream. Information presented herein is required by users to design compatible interfaces and assure effective utilization of this encoder system. GSFC/Wallops Flight Facility has flown approximately 50 of these systems through 1984 on sounding rockets with no inflight failures. Aydin Vector manufactures all of the components for these systems.

  15. Parameter study of dual-mode space nuclear fission solid core power and propulsion systems, NUROC3A. AMS report No. 1239c

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

    Smith, W.W.; Layton, J.P.

    1976-09-13

    The three-volume report describes a dual-mode nuclear space power and propulsion system concept that employs an advanced solid-core nuclear fission reactor coupled via heat pipes to one of several electric power conversion systems. The NUROC3A systems analysis code was designed to provide the user with performance characteristics of the dual-mode system. Volume 3 describes utilization of the NUROC3A code to produce a detailed parameter study of the system.

  16. Maximum aposteriori joint source/channel coding

    NASA Technical Reports Server (NTRS)

    Sayood, Khalid; Gibson, Jerry D.

    1991-01-01

    A maximum aposteriori probability (MAP) approach to joint source/channel coder design is presented in this paper. This method attempts to explore a technique for designing joint source/channel codes, rather than ways of distributing bits between source coders and channel coders. For a nonideal source coder, MAP arguments are used to design a decoder which takes advantage of redundancy in the source coder output to perform error correction. Once the decoder is obtained, it is analyzed with the purpose of obtaining 'desirable properties' of the channel input sequence for improving overall system performance. Finally, an encoder design which incorporates these properties is proposed.

  17. Upgrades to the NESS (Nuclear Engine System Simulation) Code

    NASA Technical Reports Server (NTRS)

    Fittje, James E.

    2007-01-01

    In support of the President's Vision for Space Exploration, the Nuclear Thermal Rocket (NTR) concept is being evaluated as a potential propulsion technology for human expeditions to the moon and Mars. The need for exceptional propulsion system performance in these missions has been documented in numerous studies, and was the primary focus of a considerable effort undertaken during the 1960's and 1970's. The NASA Glenn Research Center is leveraging this past NTR investment in their vehicle concepts and mission analysis studies with the aid of the Nuclear Engine System Simulation (NESS) code. This paper presents the additional capabilities and upgrades made to this code in order to perform higher fidelity NTR propulsion system analysis and design.

  18. Oak Ridge Spallation Neutron Source (ORSNS) target station design integration

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

    McManamy, T.; Booth, R.; Cleaves, J.

    1996-06-01

    The conceptual design for a 1- to 3-MW short pulse spallation source with a liquid mercury target has been started recently. The design tools and methods being developed to define requirements, integrate the work, and provide early cost guidance will be presented with a summary of the current target station design status. The initial design point was selected with performance and cost estimate projections by a systems code. This code was developed recently using cost estimates from the Brookhaven Pulsed Spallation Neutron Source study and experience from the Advanced Neutron Source Project`s conceptual design. It will be updated and improvedmore » as the design develops. Performance was characterized by a simplified figure of merit based on a ratio of neutron production to costs. A work breakdown structure was developed, with simplified systems diagrams used to define interfaces and system responsibilities. A risk assessment method was used to identify potential problems, to identify required research and development (R&D), and to aid contingency development. Preliminary 3-D models of the target station are being used to develop remote maintenance concepts and to estimate costs.« less

  19. Pre-engineering Spaceflight Validation of Environmental Models and the 2005 HZETRN Simulation Code

    NASA Technical Reports Server (NTRS)

    Nealy, John E.; Cucinotta, Francis A.; Wilson, John W.; Badavi, Francis F.; Dachev, Ts. P.; Tomov, B. T.; Walker, Steven A.; DeAngelis, Giovanni; Blattnig, Steve R.; Atwell, William

    2006-01-01

    The HZETRN code has been identified by NASA for engineering design in the next phase of space exploration highlighting a return to the Moon in preparation for a Mars mission. In response, a new series of algorithms beginning with 2005 HZETRN, will be issued by correcting some prior limitations and improving control of propagated errors along with established code verification processes. Code validation processes will use new/improved low Earth orbit (LEO) environmental models with a recently improved International Space Station (ISS) shield model to validate computational models and procedures using measured data aboard ISS. These validated models will provide a basis for flight-testing the designs of future space vehicles and systems of the Constellation program in the LEO environment.

  20. Application of CFD codes to the design and development of propulsion systems

    NASA Technical Reports Server (NTRS)

    Lord, W. K.; Pickett, G. F.; Sturgess, G. J.; Weingold, H. D.

    1987-01-01

    The internal flows of aerospace propulsion engines have certain common features that are amenable to analysis through Computational Fluid Dynamics (CFD) computer codes. Although the application of CFD to engineering problems in engines was delayed by the complexities associated with internal flows, many codes with different capabilities are now being used as routine design tools. This is illustrated by examples taken from the aircraft gas turbine engine of flows calculated with potential flow, Euler flow, parabolized Navier-Stokes, and Navier-Stokes codes. Likely future directions of CFD applied to engine flows are described, and current barriers to continued progress are highlighted. The potential importance of the Numerical Aerodynamic Simulator (NAS) to resolution of these difficulties is suggested.

  1. A Very Low Cost BCH Decoder for High Immunity of On-Chip Memories

    NASA Astrophysics Data System (ADS)

    Seo, Haejun; Han, Sehwan; Heo, Yoonseok; Cho, Taewon

    BCH(Bose-Chaudhuri-Hoquenbhem) code, a type of block codes-cyclic codes, has very strong error-correcting ability which is vital for performing the error protection on the memory system. BCH code has many kinds of dual algorithms, PGZ(Pererson-Gorenstein-Zierler) algorithm out of them is advantageous in view of correcting the errors through the simple calculation in t value. However, this is problematic when this becomes 0 (divided by zero) in case ν ≠ t. In this paper, the circuit would be simplified by suggesting the multi-mode hardware architecture in preparation that v were 0~3. First, production cost would be less thanks to the smaller number of gates. Second, lessening power consumption could lengthen the recharging period. The very low cost and simple datapath make our design a good choice in small-footprint SoC(System on Chip) as ECC(Error Correction Code/Circuit) in memory system.

  2. A Novel Design of Reconfigurable Wavelength-Time Optical Codes to Enhance Security in Optical CDMA Networks

    NASA Astrophysics Data System (ADS)

    Nasaruddin; Tsujioka, Tetsuo

    An optical CDMA (OCDMA) system is a flexible technology for future broadband multiple access networks. A secure OCDMA network in broadband optical access technologies is also becoming an issue of great importance. In this paper, we propose novel reconfigurable wavelength-time (W-T) optical codes that lead to secure transmission in OCDMA networks. The proposed W-T optical codes are constructed by using quasigroups (QGs) for wavelength hopping and one-dimensional optical orthogonal codes (OOCs) for time spreading; we call them QGs/OOCs. Both QGs and OOCs are randomly generated by a computer search to ensure that an eavesdropper could not improve its interception performance by making use of the coding structure. Then, the proposed reconfigurable QGs/OOCs can provide more codewords, and many different code set patterns, which differ in both wavelength and time positions for given code parameters. Moreover, the bit error probability of the proposed codes is analyzed numerically. To realize the proposed codes, a secure system is proposed by employing reconfigurable encoders/decoders based on array waveguide gratings (AWGs), which allow the users to change their codeword patterns to protect against eavesdropping. Finally, the probability of breaking a certain codeword in the proposed system is evaluated analytically. The results show that the proposed codes and system can provide a large codeword pattern, and decrease the probability of breaking a certain codeword, to enhance OCDMA network security.

  3. Nonlinear ship waves and computational fluid dynamics

    PubMed Central

    MIYATA, Hideaki; ORIHARA, Hideo; SATO, Yohei

    2014-01-01

    Research works undertaken in the first author’s laboratory at the University of Tokyo over the past 30 years are highlighted. Finding of the occurrence of nonlinear waves (named Free-Surface Shock Waves) in the vicinity of a ship advancing at constant speed provided the start-line for the progress of innovative technologies in the ship hull-form design. Based on these findings, a multitude of the Computational Fluid Dynamic (CFD) techniques have been developed over this period, and are highlighted in this paper. The TUMMAC code has been developed for wave problems, based on a rectangular grid system, while the WISDAM code treats both wave and viscous flow problems in the framework of a boundary-fitted grid system. These two techniques are able to cope with almost all fluid dynamical problems relating to ships, including the resistance, ship’s motion and ride-comfort issues. Consequently, the two codes have contributed significantly to the progress in the technology of ship design, and now form an integral part of the ship-designing process. PMID:25311139

  4. Simulation and optimization study of a solar seasonal storage district heating system: the Fox River Valley case study

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

    Michaels, A.I.; Sillman, S.; Baylin, F.

    1983-05-01

    A central solar-heating plant with seasonal heat storage in a deep underground aquifer is designed by means of a solar-seasonal-storage-system simulation code based on the Solar Energy Research Institute (SERI) code for Solar Annual Storage Simulation (SASS). This Solar Seasonal Storage Plant is designed to supply close to 100% of the annual heating and domestic-hot-water (DHW) load of a hypothetical new community, the Fox River Valley Project, for a location in Madison, Wisconsin. Some analyses are also carried out for Boston, Massachusetts and Copenhagen, Denmark, as an indication of weather and insolation effects. Analyses are conducted for five different typesmore » of solar collectors, and for an alternate system utilizing seasonal storage in a large water tank. Predicted seasonal performance and system and storage costs are calculated. To provide some validation of the SASS results, a simulation of the solar system with seasonal storage in a large water tank is also carried out with a modified version of the Swedish Solar Seasonal Storage Code MINSUN.« less

  5. Improved heliostat field design for solar tower plants

    NASA Astrophysics Data System (ADS)

    Collado, Francisco J.; Guallar, Jesús

    2017-06-01

    In solar power tower (SPT) systems, selecting the optimum location of thousands of heliostats and the most profitable tower height and receiver size remains a challenge. Campo code is prepared for the detailed design of such plants in particular, the optimum layout, provided that the plant size is known. Therefore, less exhaustive codes, as DELSOL3, are also needed to perform preliminary parametric analysis that narrows the most economic size of the plant.

  6. Model-based software design

    NASA Technical Reports Server (NTRS)

    Iscoe, Neil; Liu, Zheng-Yang; Feng, Guohui; Yenne, Britt; Vansickle, Larry; Ballantyne, Michael

    1992-01-01

    Domain-specific knowledge is required to create specifications, generate code, and understand existing systems. Our approach to automating software design is based on instantiating an application domain model with industry-specific knowledge and then using that model to achieve the operational goals of specification elicitation and verification, reverse engineering, and code generation. Although many different specification models can be created from any particular domain model, each specification model is consistent and correct with respect to the domain model.

  7. RECOMMENDED SUB-SLAB DEPRESSURIZATION SYSTEMS DESIGN STANDARD OF THE FLORIDA RADON RESEARCH PROGRAM

    EPA Science Inventory

    The report recommends sub-slab depressurization systems design criteria to the State of Florida's Department of Community Affairs for their building code for radon resistant houses. Numerous details are set forth in the full report. Primary criteria include: (1) the operating soi...

  8. Integrated system for production of neutronics and photonics calculational constants. Program SIGMA1 (Version 77-1): Doppler broaden evaluated cross sections in the Evaluated Nuclear Data File/Version B (ENDF/B) format

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

    Cullen, D.E.

    1977-01-12

    A code, SIGMA1, has been designed to Doppler broaden evaluated cross sections in the ENDF/B format. The code can only be applied to tabulated data that vary linearly in energy and cross section between tabulated points. This report describes the methods used in the code and serves as a user's guide to the code.

  9. The CCONE Code System and its Application to Nuclear Data Evaluation for Fission and Other Reactions

    NASA Astrophysics Data System (ADS)

    Iwamoto, O.; Iwamoto, N.; Kunieda, S.; Minato, F.; Shibata, K.

    2016-01-01

    A computer code system, CCONE, was developed for nuclear data evaluation within the JENDL project. The CCONE code system integrates various nuclear reaction models needed to describe nucleon, light charged nuclei up to alpha-particle and photon induced reactions. The code is written in the C++ programming language using an object-oriented technology. At first, it was applied to neutron-induced reaction data on actinides, which were compiled into JENDL Actinide File 2008 and JENDL-4.0. It has been extensively used in various nuclear data evaluations for both actinide and non-actinide nuclei. The CCONE code has been upgraded to nuclear data evaluation at higher incident energies for neutron-, proton-, and photon-induced reactions. It was also used for estimating β-delayed neutron emission. This paper describes the CCONE code system indicating the concept and design of coding and inputs. Details of the formulation for modelings of the direct, pre-equilibrium and compound reactions are presented. Applications to the nuclear data evaluations such as neutron-induced reactions on actinides and medium-heavy nuclei, high-energy nucleon-induced reactions, photonuclear reaction and β-delayed neutron emission are mentioned.

  10. Wavelength Coded Image Transmission and Holographic Optical Elements.

    DTIC Science & Technology

    1984-08-20

    system has been designed and built for transmitting images of diffusely reflecting objects through optical fibers and displaying those images at a...passive components at the end of a fiber-optic designed to transmit high-resolution images of diffusely imaging system as described in this paper... designing a system for viewing diffusely reflecting The authors are with University of Minnesota. Electrical Engi- objects, one must consider that a

  11. Simplified APC for Space Shuttle applications. [Adaptive Predictive Coding for speech transmission

    NASA Technical Reports Server (NTRS)

    Hutchins, S. E.; Batson, B. H.

    1975-01-01

    This paper describes an 8 kbps adaptive predictive digital speech transmission system which was designed for potential use in the Space Shuttle Program. The system was designed to provide good voice quality in the presence of both cabin noise on board the Shuttle and the anticipated bursty channel. Minimal increase in size, weight, and power over the current high data rate system was also a design objective.

  12. Advanced GF(32) nonbinary LDPC coded modulation with non-uniform 9-QAM outperforming star 8-QAM.

    PubMed

    Liu, Tao; Lin, Changyu; Djordjevic, Ivan B

    2016-06-27

    In this paper, we first describe a 9-symbol non-uniform signaling scheme based on Huffman code, in which different symbols are transmitted with different probabilities. By using the Huffman procedure, prefix code is designed to approach the optimal performance. Then, we introduce an algorithm to determine the optimal signal constellation sets for our proposed non-uniform scheme with the criterion of maximizing constellation figure of merit (CFM). The proposed nonuniform polarization multiplexed signaling 9-QAM scheme has the same spectral efficiency as the conventional 8-QAM. Additionally, we propose a specially designed GF(32) nonbinary quasi-cyclic LDPC code for the coded modulation system based on the 9-QAM non-uniform scheme. Further, we study the efficiency of our proposed non-uniform 9-QAM, combined with nonbinary LDPC coding, and demonstrate by Monte Carlo simulation that the proposed GF(23) nonbinary LDPC coded 9-QAM scheme outperforms nonbinary LDPC coded uniform 8-QAM by at least 0.8dB.

  13. Error control for reliable digital data transmission and storage systems

    NASA Technical Reports Server (NTRS)

    Costello, D. J., Jr.; Deng, R. H.

    1985-01-01

    A problem in designing semiconductor memories is to provide some measure of error control without requiring excessive coding overhead or decoding time. In LSI and VLSI technology, memories are often organized on a multiple bit (or byte) per chip basis. For example, some 256K-bit DRAM's are organized in 32Kx8 bit-bytes. Byte oriented codes such as Reed Solomon (RS) codes can provide efficient low overhead error control for such memories. However, the standard iterative algorithm for decoding RS codes is too slow for these applications. In this paper we present some special decoding techniques for extended single-and-double-error-correcting RS codes which are capable of high speed operation. These techniques are designed to find the error locations and the error values directly from the syndrome without having to use the iterative alorithm to find the error locator polynomial. Two codes are considered: (1) a d sub min = 4 single-byte-error-correcting (SBEC), double-byte-error-detecting (DBED) RS code; and (2) a d sub min = 6 double-byte-error-correcting (DBEC), triple-byte-error-detecting (TBED) RS code.

  14. Advanced software development workstation project: Engineering scripting language. Graphical editor

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Software development is widely considered to be a bottleneck in the development of complex systems, both in terms of development and in terms of maintenance of deployed systems. Cost of software development and maintenance can also be very high. One approach to reducing costs and relieving this bottleneck is increasing the reuse of software designs and software components. A method for achieving such reuse is a software parts composition system. Such a system consists of a language for modeling software parts and their interfaces, a catalog of existing parts, an editor for combining parts, and a code generator that takes a specification and generates code for that application in the target language. The Advanced Software Development Workstation is intended to be an expert system shell designed to provide the capabilities of a software part composition system.

  15. System Synchronizes Recordings from Separated Video Cameras

    NASA Technical Reports Server (NTRS)

    Nail, William; Nail, William L.; Nail, Jasper M.; Le, Doung T.

    2009-01-01

    A system of electronic hardware and software for synchronizing recordings from multiple, physically separated video cameras is being developed, primarily for use in multiple-look-angle video production. The system, the time code used in the system, and the underlying method of synchronization upon which the design of the system is based are denoted generally by the term "Geo-TimeCode(TradeMark)." The system is embodied mostly in compact, lightweight, portable units (see figure) denoted video time-code units (VTUs) - one VTU for each video camera. The system is scalable in that any number of camera recordings can be synchronized. The estimated retail price per unit would be about $350 (in 2006 dollars). The need for this or another synchronization system external to video cameras arises because most video cameras do not include internal means for maintaining synchronization with other video cameras. Unlike prior video-camera-synchronization systems, this system does not depend on continuous cable or radio links between cameras (however, it does depend on occasional cable links lasting a few seconds). Also, whereas the time codes used in prior video-camera-synchronization systems typically repeat after 24 hours, the time code used in this system does not repeat for slightly more than 136 years; hence, this system is much better suited for long-term deployment of multiple cameras.

  16. Video Monitoring a Simulation-Based Quality Improvement Program in Bihar, India.

    PubMed

    Dyer, Jessica; Spindler, Hilary; Christmas, Amelia; Shah, Malay Bharat; Morgan, Melissa; Cohen, Susanna R; Sterne, Jason; Mahapatra, Tanmay; Walker, Dilys

    2018-04-01

    Simulation-based training has become an accepted clinical training andragogy in high-resource settings with its use increasing in low-resource settings. Video recordings of simulated scenarios are commonly used by facilitators. Beyond using the videos during debrief sessions, researchers can also analyze the simulation videos to quantify technical and nontechnical skills during simulated scenarios over time. Little is known about the feasibility and use of large-scale systems to video record and analyze simulation and debriefing data for monitoring and evaluation in low-resource settings. This manuscript describes the process of designing and implementing a large-scale video monitoring system. Mentees and Mentors were consented and all simulations and debriefs conducted at 320 Primary Health Centers (PHCs) were video recorded. The system design, number of video recordings, and inter-rater reliability of the coded videos were assessed. The final dataset included a total of 11,278 videos. Overall, a total of 2,124 simulation videos were coded and 183 (12%) were blindly double-coded. For the double-coded sample, the average inter-rater reliability (IRR) scores were 80% for nontechnical skills, and 94% for clinical technical skills. Among 4,450 long debrief videos received, 216 were selected for coding and all were double-coded. Data quality of simulation videos was found to be very good in terms of recorded instances of "unable to see" and "unable to hear" in Phases 1 and 2. This study demonstrates that video monitoring systems can be effectively implemented at scale in resource limited settings. Further, video monitoring systems can play several vital roles within program implementation, including monitoring and evaluation, provision of actionable feedback to program implementers, and assurance of program fidelity.

  17. MILCOM '85 - Military Communications Conference, Boston, MA, October 20-23, 1985, Conference Record. Volumes 1, 2, & 3

    NASA Astrophysics Data System (ADS)

    The present conference on the development status of communications systems in the context of electronic warfare gives attention to topics in spread spectrum code acquisition, digital speech technology, fiber-optics communications, free space optical communications, the networking of HF systems, and applications and evaluation methods for digital speech. Also treated are issues in local area network system design, coding techniques and applications, technology applications for HF systems, receiver technologies, software development status, channel simultion/prediction methods, C3 networking spread spectrum networks, the improvement of communication efficiency and reliability through technical control methods, mobile radio systems, and adaptive antenna arrays. Finally, communications system cost analyses, spread spectrum performance, voice and image coding, switched networks, and microwave GaAs ICs, are considered.

  18. Hypersonic CFD applications for the National Aero-Space Plane

    NASA Technical Reports Server (NTRS)

    Richardson, Pamela F.; Mcclinton, Charles R.; Bittner, Robert D.; Dilley, A. Douglas; Edwards, Kelvin W.

    1989-01-01

    Design and analysis of the NASP depends heavily upon developing the critical technology areas that cover the entire engineering design of the vehicle. These areas include materials, structures, propulsion systems, propellants, integration of airframe and propulsion systems, controls, subsystems, and aerodynamics areas. Currently, verification of many of the classical engineering tools relies heavily on computational fluid dynamics. Advances are being made in the development of CFD codes to accomplish nose-to-tail analyses for hypersonic aircraft. Additional details involving the partial development, analysis, verification, and application of the CFL3D code and the SPARK combustor code are discussed. A nonequilibrium version of CFL3D that is presently being developed and tested is also described. Examples are given of portion calculations for research hypersonic aircraft geometries and comparisons with experiment data show good agreement.

  19. Thermoelectric pump performance analysis computer code

    NASA Technical Reports Server (NTRS)

    Johnson, J. L.

    1973-01-01

    A computer program is presented that was used to analyze and design dual-throat electromagnetic dc conduction pumps for the 5-kwe ZrH reactor thermoelectric system. In addition to a listing of the code and corresponding identification of symbols, the bases for this analytical model are provided.

  20. Integrated Design of Undepressed Collector for Low Power Gyrotron

    NASA Astrophysics Data System (ADS)

    Kumar, Anil; Goswami, Uttam K.; Poonia, Sunita; Singh, Udaybir; Kumar, Nitin; Alaria, M. K.; Bera, A.; Khatun, Hasina; Sinha, A. K.

    2011-06-01

    A 42 GHz, 200 kW continuous wave (CW) gyrotron, operating at TE03 mode is under development for the electron cyclotron resonance plasma heating of the Indian TOKAMAK system. The gyrotron is made up of an undepressed collector. The undepressed collector is simple to design and cost effective. In this paper, a detailed design study of the undepressed collector for the 42 GHz gyrotron is presented. The EGUN code is used to analyze the spent electron beam trajectory for the maximum spread to reduce the power loading on the collector surface. To achieve wall loading ≤1 kW/cm2, a collector with a length of 800 mm and a radius of 42.5 mm is designed. The design also includes the three magnet systems around the collector for maximum and uniform beam spread. The thermal and the structural analyses are done using the ANSYS code to optimize the collector structure and dimensions with tolerance.

  1. CELCAP: A Computer Model for Cogeneration System Analysis

    NASA Technical Reports Server (NTRS)

    1985-01-01

    A description of the CELCAP cogeneration analysis program is presented. A detailed description of the methodology used by the Naval Civil Engineering Laboratory in developing the CELCAP code and the procedures for analyzing cogeneration systems for a given user are given. The four engines modeled in CELCAP are: gas turbine with exhaust heat boiler, diesel engine with waste heat boiler, single automatic-extraction steam turbine, and back-pressure steam turbine. Both the design point and part-load performances are taken into account in the engine models. The load model describes how the hourly electric and steam demand of the user is represented by 24 hourly profiles. The economic model describes how the annual and life-cycle operating costs that include the costs of fuel, purchased electricity, and operation and maintenance of engines and boilers are calculated. The CELCAP code structure and principal functions of the code are described to how the various components of the code are related to each other. Three examples of the application of the CELCAP code are given to illustrate the versatility of the code. The examples shown represent cases of system selection, system modification, and system optimization.

  2. Validation of a Monte Carlo code system for grid evaluation with interference effect on Rayleigh scattering

    NASA Astrophysics Data System (ADS)

    Zhou, Abel; White, Graeme L.; Davidson, Rob

    2018-02-01

    Anti-scatter grids are commonly used in x-ray imaging systems to reduce scatter radiation reaching the image receptor. Anti-scatter grid performance and validation can be simulated through use of Monte Carlo (MC) methods. Our recently reported work has modified existing MC codes resulting in improved performance when simulating x-ray imaging. The aim of this work is to validate the transmission of x-ray photons in grids from the recently reported new MC codes against experimental results and results previously reported in other literature. The results of this work show that the scatter-to-primary ratio (SPR), the transmissions of primary (T p), scatter (T s), and total (T t) radiation determined using this new MC code system have strong agreement with the experimental results and the results reported in the literature. T p, T s, T t, and SPR determined in this new MC simulation code system are valid. These results also show that the interference effect on Rayleigh scattering should not be neglected in both mammographic and general grids’ evaluation. Our new MC simulation code system has been shown to be valid and can be used for analysing and evaluating the designs of grids.

  3. A large scale software system for simulation and design optimization of mechanical systems

    NASA Technical Reports Server (NTRS)

    Dopker, Bernhard; Haug, Edward J.

    1989-01-01

    The concept of an advanced integrated, networked simulation and design system is outlined. Such an advanced system can be developed utilizing existing codes without compromising the integrity and functionality of the system. An example has been used to demonstrate the applicability of the concept of the integrated system outlined here. The development of an integrated system can be done incrementally. Initial capabilities can be developed and implemented without having a detailed design of the global system. Only a conceptual global system must exist. For a fully integrated, user friendly design system, further research is needed in the areas of engineering data bases, distributed data bases, and advanced user interface design.

  4. A hydrogen-oxygen rocket engine coolant passage design program (RECOP) for fluid-cooled thrust chambers and nozzles

    NASA Technical Reports Server (NTRS)

    Tomsik, Thomas M.

    1994-01-01

    The design of coolant passages in regeneratively cooled thrust chambers is critical to the operation and safety of a rocket engine system. Designing a coolant passage is a complex thermal and hydraulic problem requiring an accurate understanding of the heat transfer between the combustion gas and the coolant. Every major rocket engine company has invested in the development of thrust chamber computer design and analysis tools; two examples are Rocketdyne's REGEN code and Aerojet's ELES program. In an effort to augment current design capabilities for government and industry, the NASA Lewis Research Center is developing a computer model to design coolant passages for advanced regeneratively cooled thrust chambers. The RECOP code incorporates state-of-the-art correlations, numerical techniques and design methods, certainly minimum requirements for generating optimum designs of future space chemical engines. A preliminary version of the RECOP model was recently completed and code validation work is in progress. This paper introduces major features of RECOP and compares the analysis to design points for the first test case engine; the Pratt & Whitney RL10A-3-3A thrust chamber.

  5. RAMONA-4B a computer code with three-dimensional neutron kinetics for BWR and SBWR system transient - user`s manual

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

    Rohatgi, U.S.; Cheng, H.S.; Khan, H.J.

    This document is the User`s Manual for the Boiling Water Reactor (BWR), and Simplified Boiling Water Reactor (SBWR) systems transient code RAMONA-4B. The code uses a three-dimensional neutron-kinetics model coupled with a multichannel, nonequilibrium, drift-flux, phase-flow model of the thermal hydraulics of the reactor vessel. The code is designed to analyze a wide spectrum of BWR core and system transients. Chapter 1 gives an overview of the code`s capabilities and limitations; Chapter 2 describes the code`s structure, lists major subroutines, and discusses the computer requirements. Chapter 3 is on code, auxillary codes, and instructions for running RAMONA-4B on Sun SPARCmore » and IBM Workstations. Chapter 4 contains component descriptions and detailed card-by-card input instructions. Chapter 5 provides samples of the tabulated output for the steady-state and transient calculations and discusses the plotting procedures for the steady-state and transient calculations. Three appendices contain important user and programmer information: lists of plot variables (Appendix A) listings of input deck for sample problem (Appendix B), and a description of the plotting program PAD (Appendix C). 24 refs., 18 figs., 11 tabs.« less

  6. ICCE/ICCAI 2000 Full & Short Papers (System Design and Development).

    ERIC Educational Resources Information Center

    2000

    This document contains the full and short papers on system design and development from ICCE/ICCAI 2000 (International Conference on Computers in Education/International Conference on Computer-Assisted Instruction) covering the following topics: a code restructuring tool to help scaffold novice programmers; a framework for Internet-based…

  7. RELAP-7 Development Updates

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

    Zhang, Hongbin; Zhao, Haihua; Gleicher, Frederick Nathan

    RELAP-7 is a nuclear systems safety analysis code being developed at the Idaho National Laboratory, and is the next generation tool in the RELAP reactor safety/systems analysis application series. RELAP-7 development began in 2011 to support the Risk Informed Safety Margins Characterization (RISMC) Pathway of the Light Water Reactor Sustainability (LWRS) program. The overall design goal of RELAP-7 is to take advantage of the previous thirty years of advancements in computer architecture, software design, numerical methods, and physical models in order to provide capabilities needed for the RISMC methodology and to support nuclear power safety analysis. The code is beingmore » developed based on Idaho National Laboratory’s modern scientific software development framework – MOOSE (the Multi-Physics Object-Oriented Simulation Environment). The initial development goal of the RELAP-7 approach focused primarily on the development of an implicit algorithm capable of strong (nonlinear) coupling of the dependent hydrodynamic variables contained in the 1-D/2-D flow models with the various 0-D system reactor components that compose various boiling water reactor (BWR) and pressurized water reactor nuclear power plants (NPPs). During Fiscal Year (FY) 2015, the RELAP-7 code has been further improved with expanded capability to support boiling water reactor (BWR) and pressurized water reactor NPPs analysis. The accumulator model has been developed. The code has also been coupled with other MOOSE-based applications such as neutronics code RattleSnake and fuel performance code BISON to perform multiphysics analysis. A major design requirement for the implicit algorithm in RELAP-7 is that it is capable of second-order discretization accuracy in both space and time, which eliminates the traditional first-order approximation errors. The second-order temporal is achieved by a second-order backward temporal difference, and the one-dimensional second-order accurate spatial discretization is achieved with the Galerkin approximation of Lagrange finite elements. During FY-2015, we have done numerical verification work to verify that the RELAP-7 code indeed achieves 2nd-order accuracy in both time and space for single phase models at the system level.« less

  8. Design evolution of large wind turbine generators

    NASA Technical Reports Server (NTRS)

    Spera, D. A.

    1979-01-01

    During the past five years, the goals of economy and reliability have led to a significant evolution in the basic design--both external and internal--of large wind turbine systems. To show the scope and nature of recent changes in wind turbine designs, development of three types are described: (1) system configuration developments; (2) computer code developments; and (3) blade technology developments.

  9. Code query by example

    NASA Astrophysics Data System (ADS)

    Vaucouleur, Sebastien

    2011-02-01

    We introduce code query by example for customisation of evolvable software products in general and of enterprise resource planning systems (ERPs) in particular. The concept is based on an initial empirical study on practices around ERP systems. We motivate our design choices based on those empirical results, and we show how the proposed solution helps with respect to the infamous upgrade problem: the conflict between the need for customisation and the need for upgrade of ERP systems. We further show how code query by example can be used as a form of lightweight static analysis, to detect automatically potential defects in large software products. Code query by example as a form of lightweight static analysis is particularly interesting in the context of ERP systems: it is often the case that programmers working in this field are not computer science specialists but more of domain experts. Hence, they require a simple language to express custom rules.

  10. Creating and Testing Simulation Software

    NASA Technical Reports Server (NTRS)

    Heinich, Christina M.

    2013-01-01

    The goal of this project is to learn about the software development process, specifically the process to test and fix components of the software. The paper will cover the techniques of testing code, and the benefits of using one style of testing over another. It will also discuss the overall software design and development lifecycle, and how code testing plays an integral role in it. Coding is notorious for always needing to be debugged due to coding errors or faulty program design. Writing tests either before or during program creation that cover all aspects of the code provide a relatively easy way to locate and fix errors, which will in turn decrease the necessity to fix a program after it is released for common use. The backdrop for this paper is the Spaceport Command and Control System (SCCS) Simulation Computer Software Configuration Item (CSCI), a project whose goal is to simulate a launch using simulated models of the ground systems and the connections between them and the control room. The simulations will be used for training and to ensure that all possible outcomes and complications are prepared for before the actual launch day. The code being tested is the Programmable Logic Controller Interface (PLCIF) code, the component responsible for transferring the information from the models to the model Programmable Logic Controllers (PLCs), basic computers that are used for very simple tasks.

  11. The Design of a Secure File Storage System

    DTIC Science & Technology

    1979-12-01

    ERROR _CODE (Przi SUCO COPE) !01ile not found; write access to dtrectorv not permitted I t := GATEKEFPER?.TICKFT ’MAIL BOX, 0) G ATE KF YP F I ~D iNC...BOX.MS’T.SUCC CODE F’OF COD? (DIOR SUCO CODE) Ifile_ not found.; Fead acceLss to directoryv file t ~TRKEPE.TIKFT MIT BOX C) GATHYP~PE-I.AWAIT (MAILBOX, C. (t+2

  12. Design of a Double Anode Magnetron Injection Gun for Q-band Gyro-TWT Using Boundary Element Method

    NASA Astrophysics Data System (ADS)

    Li, Zhiliang; Feng, Jinjun; Liu, Bentian

    2018-04-01

    This paper presents a novel design code for double anode magnetron injection guns (MIGs) in gyro-devices based on boundary element method (BEM). The physical and mathematical models were constructed, and then the code using BEM for MIG's calculation was developed. Using the code, a double anode MIG for a Q-band gyrotron traveling-wave tube (gyro-TWT) amplifier operating in the circular TE01 mode at the fundamental cyclotron harmonic was designed. In order to verify the reliability of this code, velocity spread and guiding center radius of the MIG simulated by the BEM code were compared with these from the commonly used EGUN code, showing a reasonable agreement. Then, a Q-band gyro-TWT was fabricated and tested. The testing results show that the device has achieved an average power of 5kW and peak power ≥ 150 kW at a 3% duty cycle within bandwidth of 2 GHz, and maximum output peak power of 220 kW, with a corresponding saturated gain of 50.9 dB and efficiency of 39.8%. This paper demonstrates that the BEM code can be used as an effective approach for analysis of electron optics system in gyro-devices.

  13. HEC Applications on Columbia Project

    NASA Technical Reports Server (NTRS)

    Taft, Jim

    2004-01-01

    NASA's Columbia system consists of a cluster of twenty 512 processor SGI Altix systems. Each of these systems is 3 TFLOP/s in peak performance - approximately the same as the entire compute capability at NAS just one year ago. Each 512p system is a single system image machine with one Linunx O5, one high performance file system, and one globally shared memory. The NAS Terascale Applications Group (TAG) is chartered to assist in scaling NASA's mission critical codes to at least 512p in order to significantly improve emergency response during flight operations, as well as provide significant improvements in the codes. and rate of scientific discovery across the scientifc disciplines within NASA's Missions. Recent accomplishments are 4x improvements to codes in the ocean modeling community, 10x performance improvements in a number of computational fluid dynamics codes used in aero-vehicle design, and 5x improvements in a number of space science codes dealing in extreme physics. The TAG group will continue its scaling work to 2048p and beyond (10240 cpus) as the Columbia system becomes fully operational and the upgrades to the SGI NUMAlink memory fabric are in place. The NUMlink uprades dramatically improve system scalability for a single application. These upgrades will allow a number of codes to execute faster at higher fidelity than ever before on any other system, thus increasing the rate of scientific discovery even further

  14. FY17 Status Report on NEAMS Neutronics Activities

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

    Lee, C. H.; Jung, Y. S.; Smith, M. A.

    2017-09-30

    Under the U.S. DOE NEAMS program, the high-fidelity neutronics code system has been developed to support the multiphysics modeling and simulation capability named SHARP. The neutronics code system includes the high-fidelity neutronics code PROTEUS, the cross section library and preprocessing tools, the multigroup cross section generation code MC2-3, the in-house meshing generation tool, the perturbation and sensitivity analysis code PERSENT, and post-processing tools. The main objectives of the NEAMS neutronics activities in FY17 are to continue development of an advanced nodal solver in PROTEUS for use in nuclear reactor design and analysis projects, implement a simplified sub-channel based thermal-hydraulic (T/H)more » capability into PROTEUS to efficiently compute the thermal feedback, improve the performance of PROTEUS-MOCEX using numerical acceleration and code optimization, improve the cross section generation tools including MC2-3, and continue to perform verification and validation tests for PROTEUS.« less

  15. Classification of finger movements by using the ultra-wide band radar.

    PubMed

    Eldosoky, Mohamed A A

    2010-12-01

    The coding system of finger movements depends on the differences in the characteristics of the muscles that are responsible for these movements. The ability of ultra-wide band (UWB) radar for use as a tool for identifying the movements of each finger is presented. This will facilitate the ability of the UWB radar in designing a coding system for the movement of fingers of each hand.

  16. ARCADIA{sup R} - A New Generation of Coupled Neutronics / Core Thermal- Hydraulics Code System at AREVA NP

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

    Curca-Tivig, Florin; Merk, Stephan; Pautz, Andreas

    2007-07-01

    Anticipating future needs of our customers and willing to concentrate synergies and competences existing in the company for the benefit of our customers, AREVA NP decided in 2002 to develop the next generation of coupled neutronics/ core thermal-hydraulic (TH) code systems for fuel assembly and core design calculations for both, PWR and BWR applications. The global CONVERGENCE project was born: after a feasibility study of one year (2002) and a conceptual phase of another year (2003), development was started at the beginning of 2004. The present paper introduces the CONVERGENCE project, presents the main feature of the new code systemmore » ARCADIA{sup R} and concludes on customer benefits. ARCADIA{sup R} is designed to meet AREVA NP market and customers' requirements worldwide. Besides state-of-the-art physical modeling, numerical performance and industrial functionality, the ARCADIA{sup R} system is featuring state-of-the-art software engineering. The new code system will bring a series of benefits for our customers: e.g. improved accuracy for heterogeneous cores (MOX/ UOX, Gd...), better description of nuclide chains, and access to local neutronics/ thermal-hydraulics and possibly thermal-mechanical information (3D pin by pin full core modeling). ARCADIA is a registered trademark of AREVA NP. (authors)« less

  17. GLOBECOM '89 - IEEE Global Telecommunications Conference and Exhibition, Dallas, TX, Nov. 27-30, 1989, Conference Record. Volumes 1, 2, & 3

    NASA Astrophysics Data System (ADS)

    The present conference discusses topics in multiwavelength network technology and its applications, advanced digital radio systems in their propagation environment, mobile radio communications, switching programmability, advancements in computer communications, integrated-network management and security, HDTV and image processing in communications, basic exchange communications radio advancements in digital switching, intelligent network evolution, speech coding for telecommunications, and multiple access communications. Also discussed are network designs for quality assurance, recent progress in coherent optical systems, digital radio applications, advanced communications technologies for mobile users, communication software for switching systems, AI and expert systems in network management, intelligent multiplexing nodes, video and image coding, network protocols and performance, system methods in quality and reliability, the design and simulation of lightwave systems, local radio networks, mobile satellite communications systems, fiber networks restoration, packet video networks, human interfaces for future networks, and lightwave networking.

  18. Parametric analysis of diffuser requirements for high expansion ratio space engine

    NASA Technical Reports Server (NTRS)

    Wojciechowski, C. J.; Anderson, P. G.

    1981-01-01

    A supersonic diffuser ejector design computer program was developed. Using empirically modified one dimensional flow methods the diffuser ejector geometry is specified by the code. The design code results for calculations up to the end of the diffuser second throat were verified. Diffuser requirements for sea level testing of high expansion ratio space engines were defined. The feasibility of an ejector system using two commonly available turbojet engines feeding two variable area ratio ejectors was demonstrated.

  19. Bar Code Labels

    NASA Technical Reports Server (NTRS)

    1988-01-01

    American Bar Codes, Inc. developed special bar code labels for inventory control of space shuttle parts and other space system components. ABC labels are made in a company-developed anodizing aluminum process and consecutively marketed with bar code symbology and human readable numbers. They offer extreme abrasion resistance and indefinite resistance to ultraviolet radiation, capable of withstanding 700 degree temperatures without deterioration and up to 1400 degrees with special designs. They offer high resistance to salt spray, cleaning fluids and mild acids. ABC is now producing these bar code labels commercially or industrial customers who also need labels to resist harsh environments.

  20. Prescription Drug Abuse Information in D.A.R.E.

    ERIC Educational Resources Information Center

    Morris, Melissa C.; Cline, Rebecca J. Welch; Weiler, Robert M.; Broadway, S. Camille

    2006-01-01

    This investigation was designed to examine prescription drug-related content and learning objectives in Drug Abuse Resistance Education (D.A.R.E.) for upper elementary and middle schools. Specific prescription-drug topics and context associated with content and objectives were coded. The coding system for topics included 126 topics organized…

  1. FAPRS Manual: Manual for the Functional Analytic Psychotherapy Rating Scale

    ERIC Educational Resources Information Center

    Callaghan, Glenn M.; Follette, William C.

    2008-01-01

    The Functional Analytic Psychotherapy Rating Scale (FAPRS) is behavioral coding system designed to capture those essential client and therapist behaviors that occur during Functional Analytic Psychotherapy (FAP). The FAPRS manual presents the purpose and rules for documenting essential aspects of FAP. The FAPRS codes are exclusive and exhaustive…

  2. Earth Observing System (EOS) Communication (Ecom) Modeling, Analysis, and Testbed (EMAT) activiy

    NASA Technical Reports Server (NTRS)

    Desai, Vishal

    1994-01-01

    This paper describes the Earth Observing System (EOS) Communication (Ecom) Modeling, Analysis, and Testbed (EMAT) activity performed by Code 540 in support of the Ecom project. Ecom is the ground-to-ground data transport system for operational EOS traffic. The National Aeronautic and Space Administration (NASA) Communications (Nascom) Division, Code 540, is responsible for implementing Ecom. Ecom interfaces with various systems to transport EOS forward link commands, return link telemetry, and science payload data. To understand the complexities surrounding the design and implementation of Ecom, it is necessary that sufficient testbedding, modeling, and analysis be conducted prior to the design phase. These activities, when grouped, are referred to as the EMAT activity. This paper describes work accomplished to date in each of the three major EMAT activities: modeling, analysis, and testbedding.

  3. Improving performance of DS-CDMA systems using chaotic complex Bernoulli spreading codes

    NASA Astrophysics Data System (ADS)

    Farzan Sabahi, Mohammad; Dehghanfard, Ali

    2014-12-01

    The most important goal of spreading spectrum communication system is to protect communication signals against interference and exploitation of information by unintended listeners. In fact, low probability of detection and low probability of intercept are two important parameters to increase the performance of the system. In Direct Sequence Code Division Multiple Access (DS-CDMA) systems, these properties are achieved by multiplying the data information in spreading sequences. Chaotic sequences, with their particular properties, have numerous applications in constructing spreading codes. Using one-dimensional Bernoulli chaotic sequence as spreading code is proposed in literature previously. The main feature of this sequence is its negative auto-correlation at lag of 1, which with proper design, leads to increase in efficiency of the communication system based on these codes. On the other hand, employing the complex chaotic sequences as spreading sequence also has been discussed in several papers. In this paper, use of two-dimensional Bernoulli chaotic sequences is proposed as spreading codes. The performance of a multi-user synchronous and asynchronous DS-CDMA system will be evaluated by applying these sequences under Additive White Gaussian Noise (AWGN) and fading channel. Simulation results indicate improvement of the performance in comparison with conventional spreading codes like Gold codes as well as similar complex chaotic spreading sequences. Similar to one-dimensional Bernoulli chaotic sequences, the proposed sequences also have negative auto-correlation. Besides, construction of complex sequences with lower average cross-correlation is possible with the proposed method.

  4. Transforming Aggregate Object-Oriented Formal Specifications to Code

    DTIC Science & Technology

    1999-03-01

    integration issues associated with a formal-based software transformation system, such as the source specification, the problem space architecture , design architecture ... design transforms, and target software transforms. Software is critical in today’s Air Force, yet its specification, design, and development

  5. Neural Coding for Effective Rehabilitation

    PubMed Central

    2014-01-01

    Successful neurological rehabilitation depends on accurate diagnosis, effective treatment, and quantitative evaluation. Neural coding, a technology for interpretation of functional and structural information of the nervous system, has contributed to the advancements in neuroimaging, brain-machine interface (BMI), and design of training devices for rehabilitation purposes. In this review, we summarized the latest breakthroughs in neuroimaging from microscale to macroscale levels with potential diagnostic applications for rehabilitation. We also reviewed the achievements in electrocorticography (ECoG) coding with both animal models and human beings for BMI design, electromyography (EMG) interpretation for interaction with external robotic systems, and robot-assisted quantitative evaluation on the progress of rehabilitation programs. Future rehabilitation would be more home-based, automatic, and self-served by patients. Further investigations and breakthroughs are mainly needed in aspects of improving the computational efficiency in neuroimaging and multichannel ECoG by selection of localized neuroinformatics, validation of the effectiveness in BMI guided rehabilitation programs, and simplification of the system operation in training devices. PMID:25258708

  6. The Athena Astrophysical MHD Code in Cylindrical Geometry

    NASA Astrophysics Data System (ADS)

    Skinner, M. A.; Ostriker, E. C.

    2011-10-01

    We have developed a method for implementing cylindrical coordinates in the Athena MHD code (Skinner & Ostriker 2010). The extension has been designed to alter the existing Cartesian-coordinates code (Stone et al. 2008) as minimally and transparently as possible. The numerical equations in cylindrical coordinates are formulated to maintain consistency with constrained transport, a central feature of the Athena algorithm, while making use of previously implemented code modules such as the eigensystems and Riemann solvers. Angular-momentum transport, which is critical in astrophysical disk systems dominated by rotation, is treated carefully. We describe modifications for cylindrical coordinates of the higher-order spatial reconstruction and characteristic evolution steps as well as the finite-volume and constrained transport updates. Finally, we have developed a test suite of standard and novel problems in one-, two-, and three-dimensions designed to validate our algorithms and implementation and to be of use to other code developers. The code is suitable for use in a wide variety of astrophysical applications and is freely available for download on the web.

  7. Capabilities needed for the next generation of thermo-hydraulic codes for use in real time applications

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

    Arndt, S.A.

    1997-07-01

    The real-time reactor simulation field is currently at a crossroads in terms of the capability to perform real-time analysis using the most sophisticated computer codes. Current generation safety analysis codes are being modified to replace simplified codes that were specifically designed to meet the competing requirement for real-time applications. The next generation of thermo-hydraulic codes will need to have included in their specifications the specific requirement for use in a real-time environment. Use of the codes in real-time applications imposes much stricter requirements on robustness, reliability and repeatability than do design and analysis applications. In addition, the need for codemore » use by a variety of users is a critical issue for real-time users, trainers and emergency planners who currently use real-time simulation, and PRA practitioners who will increasingly use real-time simulation for evaluating PRA success criteria in near real-time to validate PRA results for specific configurations and plant system unavailabilities.« less

  8. Automatic Implementation of Ttethernet-Based Time-Triggered Avionics Applications

    NASA Astrophysics Data System (ADS)

    Gorcitz, Raul Adrian; Carle, Thomas; Lesens, David; Monchaux, David; Potop-Butucaruy, Dumitru; Sorel, Yves

    2015-09-01

    The design of safety-critical embedded systems such as those used in avionics still involves largely manual phases. But in avionics the definition of standard interfaces embodied in standards such as ARINC 653 or TTEthernet should allow the definition of fully automatic code generation flows that reduce the costs while improving the quality of the generated code, much like compilers have done when replacing manual assembly coding. In this paper, we briefly present such a fully automatic implementation tool, called Lopht, for ARINC653-based time-triggered systems, and then explain how it is currently extended to include support for TTEthernet networks.

  9. An integrated radiation physics computer code system.

    NASA Technical Reports Server (NTRS)

    Steyn, J. J.; Harris, D. W.

    1972-01-01

    An integrated computer code system for the semi-automatic and rapid analysis of experimental and analytic problems in gamma photon and fast neutron radiation physics is presented. Such problems as the design of optimum radiation shields and radioisotope power source configurations may be studied. The system codes allow for the unfolding of complex neutron and gamma photon experimental spectra. Monte Carlo and analytic techniques are used for the theoretical prediction of radiation transport. The system includes a multichannel pulse-height analyzer scintillation and semiconductor spectrometer coupled to an on-line digital computer with appropriate peripheral equipment. The system is geometry generalized as well as self-contained with respect to material nuclear cross sections and the determination of the spectrometer response functions. Input data may be either analytic or experimental.

  10. Edge-diffraction effects in RCS predictions and their importance in systems analysis

    NASA Astrophysics Data System (ADS)

    Friess, W. F.; Klement, D.; Ruppel, M.; Stein, Volker

    1996-06-01

    In developing RCS prediction codes a variety of physical effects such as the edge diffraction effect have to be considered with the consequence that the computer effort increases considerably. This fact limits the field of application of such codes, especially if the RCS data serve as input parameters for system simulators which very often need these data for a high number of observation angles and/or frequencies. Vice versa the issues of a system analysis can be used to estimate the relevance of physical effects under system viewpoints and to rank them according to their magnitude. This paper tries to evaluate the importance of RCS predictions containing an edge diffracted field for systems analysis. A double dihedral with a strong depolarizing behavior and a generic airplane design containing many arbitrarily oriented edges are used as test structures. Data of the scattered field are generated by the RCS computer code SIGMA with and without including edge diffraction effects. These data are submitted to the code DORA to determine radar range and radar detectibility and to a SAR simulator code to generate SAR imagery. In both cases special scenarios are assumed. The essential features of the computer codes in their current state are described, the results are presented and discussed under systems viewpoints.

  11. Research on Formation of Microsatellite Communication with Genetic Algorithm

    PubMed Central

    Wu, Guoqiang; Bai, Yuguang; Sun, Zhaowei

    2013-01-01

    For the formation of three microsatellites which fly in the same orbit and perform three-dimensional solid mapping for terra, this paper proposes an optimizing design method of space circular formation order based on improved generic algorithm and provides an intersatellite direct spread spectrum communication system. The calculating equation of LEO formation flying satellite intersatellite links is guided by the special requirements of formation-flying microsatellite intersatellite links, and the transmitter power is also confirmed throughout the simulation. The method of space circular formation order optimizing design based on improved generic algorithm is given, and it can keep formation order steady for a long time under various absorb impetus. The intersatellite direct spread spectrum communication system is also provided. It can be found that, when the distance is 1 km and the data rate is 1 Mbps, the input wave matches preferably with the output wave. And LDPC code can improve the communication performance. The correct capability of (512, 256) LDPC code is better than (2, 1, 7) convolution code, distinctively. The design system can satisfy the communication requirements of microsatellites. So, the presented method provides a significant theory foundation for formation-flying and intersatellite communication. PMID:24078796

  12. Research on formation of microsatellite communication with genetic algorithm.

    PubMed

    Wu, Guoqiang; Bai, Yuguang; Sun, Zhaowei

    2013-01-01

    For the formation of three microsatellites which fly in the same orbit and perform three-dimensional solid mapping for terra, this paper proposes an optimizing design method of space circular formation order based on improved generic algorithm and provides an intersatellite direct spread spectrum communication system. The calculating equation of LEO formation flying satellite intersatellite links is guided by the special requirements of formation-flying microsatellite intersatellite links, and the transmitter power is also confirmed throughout the simulation. The method of space circular formation order optimizing design based on improved generic algorithm is given, and it can keep formation order steady for a long time under various absorb impetus. The intersatellite direct spread spectrum communication system is also provided. It can be found that, when the distance is 1 km and the data rate is 1 Mbps, the input wave matches preferably with the output wave. And LDPC code can improve the communication performance. The correct capability of (512, 256) LDPC code is better than (2, 1, 7) convolution code, distinctively. The design system can satisfy the communication requirements of microsatellites. So, the presented method provides a significant theory foundation for formation-flying and intersatellite communication.

  13. Is QR code an optimal data container in optical encryption systems from an error-correction coding perspective?

    PubMed

    Jiao, Shuming; Jin, Zhi; Zhou, Changyuan; Zou, Wenbin; Li, Xia

    2018-01-01

    Quick response (QR) code has been employed as a data carrier for optical cryptosystems in many recent research works, and the error-correction coding mechanism allows the decrypted result to be noise free. However, in this paper, we point out for the first time that the Reed-Solomon coding algorithm in QR code is not a very suitable option for the nonlocally distributed speckle noise in optical cryptosystems from an information coding perspective. The average channel capacity is proposed to measure the data storage capacity and noise-resistant capability of different encoding schemes. We design an alternative 2D barcode scheme based on Bose-Chaudhuri-Hocquenghem (BCH) coding, which demonstrates substantially better average channel capacity than QR code in numerical simulated optical cryptosystems.

  14. Object Based Numerical Zooming Between the NPSS Version 1 and a 1-Dimensional Meanline High Pressure Compressor Design Analysis Code

    NASA Technical Reports Server (NTRS)

    Follen, G.; Naiman, C.; auBuchon, M.

    2000-01-01

    Within NASA's High Performance Computing and Communication (HPCC) program, NASA Glenn Research Center is developing an environment for the analysis/design of propulsion systems for aircraft and space vehicles called the Numerical Propulsion System Simulation (NPSS). The NPSS focuses on the integration of multiple disciplines such as aerodynamics, structures, and heat transfer, along with the concept of numerical zooming between 0- Dimensional to 1-, 2-, and 3-dimensional component engine codes. The vision for NPSS is to create a "numerical test cell" enabling full engine simulations overnight on cost-effective computing platforms. Current "state-of-the-art" engine simulations are 0-dimensional in that there is there is no axial, radial or circumferential resolution within a given component (e.g. a compressor or turbine has no internal station designations). In these 0-dimensional cycle simulations the individual component performance characteristics typically come from a table look-up (map) with adjustments for off-design effects such as variable geometry, Reynolds effects, and clearances. Zooming one or more of the engine components to a higher order, physics-based analysis means a higher order code is executed and the results from this analysis are used to adjust the 0-dimensional component performance characteristics within the system simulation. By drawing on the results from more predictive, physics based higher order analysis codes, "cycle" simulations are refined to closely model and predict the complex physical processes inherent to engines. As part of the overall development of the NPSS, NASA and industry began the process of defining and implementing an object class structure that enables Numerical Zooming between the NPSS Version I (0-dimension) and higher order 1-, 2- and 3-dimensional analysis codes. The NPSS Version I preserves the historical cycle engineering practices but also extends these classical practices into the area of numerical zooming for use within a companies' design system. What follows here is a description of successfully zooming I-dimensional (row-by-row) high pressure compressor results back to a NPSS engine 0-dimension simulation and a discussion of the results illustrated using an advanced data visualization tool. This type of high fidelity system-level analysis, made possible by the zooming capability of the NPSS, will greatly improve the fidelity of the engine system simulation and enable the engine system to be "pre-validated" prior to commitment to engine hardware.

  15. Automatic Synthesis of UML Designs from Requirements in an Iterative Process

    NASA Technical Reports Server (NTRS)

    Schumann, Johann; Whittle, Jon; Clancy, Daniel (Technical Monitor)

    2001-01-01

    The Unified Modeling Language (UML) is gaining wide popularity for the design of object-oriented systems. UML combines various object-oriented graphical design notations under one common framework. A major factor for the broad acceptance of UML is that it can be conveniently used in a highly iterative, Use Case (or scenario-based) process (although the process is not a part of UML). Here, the (pre-) requirements for the software are specified rather informally as Use Cases and a set of scenarios. A scenario can be seen as an individual trace of a software artifact. Besides first sketches of a class diagram to illustrate the static system breakdown, scenarios are a favorite way of communication with the customer, because scenarios describe concrete interactions between entities and are thus easy to understand. Scenarios with a high level of detail are often expressed as sequence diagrams. Later in the design and implementation stage (elaboration and implementation phases), a design of the system's behavior is often developed as a set of statecharts. From there (and the full-fledged class diagram), actual code development is started. Current commercial UML tools support this phase by providing code generators for class diagrams and statecharts. In practice, it can be observed that the transition from requirements to design to code is a highly iterative process. In this talk, a set of algorithms is presented which perform reasonable synthesis and transformations between different UML notations (sequence diagrams, Object Constraint Language (OCL) constraints, statecharts). More specifically, we will discuss the following transformations: Statechart synthesis, introduction of hierarchy, consistency of modifications, and "design-debugging".

  16. Design Producibility Assessment System

    DTIC Science & Technology

    1989-06-30

    Data Base Material Code 17 - 4PH Manufactu Description Precipitation-Handling, corrosion-resist steel Strategic? No Strip Sheet Bar Wire Tube Yes Yes Yes...planned production quantity: 10000 PRODUCTION FACILITIES 5 Select the design material: 17 - 4PH <PgUp> Page Up, <PgDn> Page Down, <Fl> Help, <Esc> Exit DPAS...vl.00 Saturday June 17 , 1989 11:06 am Design Producibility Assessment System Select the design material: 17 - 4PH Select the design material’s form

  17. RIES - Rijnland Internet Election System: A Cursory Study of Published Source Code

    NASA Astrophysics Data System (ADS)

    Gonggrijp, Rop; Hengeveld, Willem-Jan; Hotting, Eelco; Schmidt, Sebastian; Weidemann, Frederik

    The Rijnland Internet Election System (RIES) is a system designed for voting in public elections over the internet. A rather cursory scan of the source code to RIES showed a significant lack of security-awareness among the programmers which - among other things - appears to have left RIES vulnerable to near-trivial attacks. If it had not been for independent studies finding problems, RIES would have been used in the 2008 Water Board elections, possibly handling a million votes or more. While RIES was more extensively studied to find cryptographic shortcomings, our work shows that more down-to-earth secure design practices can be at least as important, and the aspects need to be examined much sooner than right before an election.

  18. A plug-in to Eclipse for VHDL source codes: functionalities

    NASA Astrophysics Data System (ADS)

    Niton, B.; Poźniak, K. T.; Romaniuk, R. S.

    The paper presents an original application, written by authors, which supports writing and edition of source codes in VHDL language. It is a step towards fully automatic, augmented code writing for photonic and electronic systems, also systems based on FPGA and/or DSP processors. An implementation is described, based on VEditor. VEditor is a free license program. Thus, the work presented in this paper supplements and extends this free license. The introduction characterizes shortly available tools on the market which serve for aiding the design processes of electronic systems in VHDL. Particular attention was put on plug-ins to the Eclipse environment and Emacs program. There are presented detailed properties of the written plug-in such as: programming extension conception, and the results of the activities of formatter, re-factorizer, code hider, and other new additions to the VEditor program.

  19. Software for Collaborative Engineering of Launch Rockets

    NASA Technical Reports Server (NTRS)

    Stanley, Thomas Troy

    2003-01-01

    The Rocket Evaluation and Cost Integration for Propulsion and Engineering software enables collaborative computing with automated exchange of information in the design and analysis of launch rockets and other complex systems. RECIPE can interact with and incorporate a variety of programs, including legacy codes, that model aspects of a system from the perspectives of different technological disciplines (e.g., aerodynamics, structures, propulsion, trajectory, aeroheating, controls, and operations) and that are used by different engineers on different computers running different operating systems. RECIPE consists mainly of (1) ISCRM a file-transfer subprogram that makes it possible for legacy codes executed in their original operating systems on their original computers to exchange data and (2) CONES an easy-to-use filewrapper subprogram that enables the integration of legacy codes. RECIPE provides a tightly integrated conceptual framework that emphasizes connectivity among the programs used by the collaborators, linking these programs in a manner that provides some configuration control while facilitating collaborative engineering tradeoff studies, including design to cost studies. In comparison with prior collaborative-engineering schemes, one based on the use of RECIPE enables fewer engineers to do more in less time.

  20. 38 CFR 39.22 - Architectural design standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) Mechanical requirements. The heating system, boilers, steam system, ventilation system and air-conditioning system shall be furnished and installed to meet all requirements of the local and State codes and... apply. (c) Plumbing requirements. Plumbing systems shall comply with all applicable local and State...

  1. Design of two-dimensional zero reference codes with cross-entropy method.

    PubMed

    Chen, Jung-Chieh; Wen, Chao-Kai

    2010-06-20

    We present a cross-entropy (CE)-based method for the design of optimum two-dimensional (2D) zero reference codes (ZRCs) in order to generate a zero reference signal for a grating measurement system and achieve absolute position, a coordinate origin, or a machine home position. In the absence of diffraction effects, the 2D ZRC design problem is known as the autocorrelation approximation. Based on the properties of the autocorrelation function, the design of the 2D ZRC is first formulated as a particular combination optimization problem. The CE method is then applied to search for an optimal 2D ZRC and thus obtain the desirable zero reference signal. Computer simulation results indicate that there are 15.38% and 14.29% reductions in the second maxima value for the 16x16 grating system with n(1)=64 and the 100x100 grating system with n(1)=300, respectively, where n(1) is the number of transparent pixels, compared with those of the conventional genetic algorithm.

  2. On the optimum signal constellation design for high-speed optical transport networks.

    PubMed

    Liu, Tao; Djordjevic, Ivan B

    2012-08-27

    In this paper, we first describe an optimum signal constellation design algorithm, which is optimum in MMSE-sense, called MMSE-OSCD, for channel capacity achieving source distribution. Secondly, we introduce a feedback channel capacity inspired optimum signal constellation design (FCC-OSCD) to further improve the performance of MMSE-OSCD, inspired by the fact that feedback channel capacity is higher than that of systems without feedback. The constellations obtained by FCC-OSCD are, however, OSNR dependent. The optimization is jointly performed together with regular quasi-cyclic low-density parity-check (LDPC) code design. Such obtained coded-modulation scheme, in combination with polarization-multiplexing, is suitable as both 400 Gb/s and multi-Tb/s optical transport enabling technology. Using large girth LDPC code, we demonstrate by Monte Carlo simulations that a 32-ary signal constellation, obtained by FCC-OSCD, outperforms previously proposed optimized 32-ary CIPQ signal constellation by 0.8 dB at BER of 10(-7). On the other hand, the LDPC-coded 16-ary FCC-OSCD outperforms 16-QAM by 1.15 dB at the same BER.

  3. DNA Barcoding through Quaternary LDPC Codes

    PubMed Central

    Tapia, Elizabeth; Spetale, Flavio; Krsticevic, Flavia; Angelone, Laura; Bulacio, Pilar

    2015-01-01

    For many parallel applications of Next-Generation Sequencing (NGS) technologies short barcodes able to accurately multiplex a large number of samples are demanded. To address these competitive requirements, the use of error-correcting codes is advised. Current barcoding systems are mostly built from short random error-correcting codes, a feature that strongly limits their multiplexing accuracy and experimental scalability. To overcome these problems on sequencing systems impaired by mismatch errors, the alternative use of binary BCH and pseudo-quaternary Hamming codes has been proposed. However, these codes either fail to provide a fine-scale with regard to size of barcodes (BCH) or have intrinsic poor error correcting abilities (Hamming). Here, the design of barcodes from shortened binary BCH codes and quaternary Low Density Parity Check (LDPC) codes is introduced. Simulation results show that although accurate barcoding systems of high multiplexing capacity can be obtained with any of these codes, using quaternary LDPC codes may be particularly advantageous due to the lower rates of read losses and undetected sample misidentification errors. Even at mismatch error rates of 10−2 per base, 24-nt LDPC barcodes can be used to multiplex roughly 2000 samples with a sample misidentification error rate in the order of 10−9 at the expense of a rate of read losses just in the order of 10−6. PMID:26492348

  4. DNA Barcoding through Quaternary LDPC Codes.

    PubMed

    Tapia, Elizabeth; Spetale, Flavio; Krsticevic, Flavia; Angelone, Laura; Bulacio, Pilar

    2015-01-01

    For many parallel applications of Next-Generation Sequencing (NGS) technologies short barcodes able to accurately multiplex a large number of samples are demanded. To address these competitive requirements, the use of error-correcting codes is advised. Current barcoding systems are mostly built from short random error-correcting codes, a feature that strongly limits their multiplexing accuracy and experimental scalability. To overcome these problems on sequencing systems impaired by mismatch errors, the alternative use of binary BCH and pseudo-quaternary Hamming codes has been proposed. However, these codes either fail to provide a fine-scale with regard to size of barcodes (BCH) or have intrinsic poor error correcting abilities (Hamming). Here, the design of barcodes from shortened binary BCH codes and quaternary Low Density Parity Check (LDPC) codes is introduced. Simulation results show that although accurate barcoding systems of high multiplexing capacity can be obtained with any of these codes, using quaternary LDPC codes may be particularly advantageous due to the lower rates of read losses and undetected sample misidentification errors. Even at mismatch error rates of 10(-2) per base, 24-nt LDPC barcodes can be used to multiplex roughly 2000 samples with a sample misidentification error rate in the order of 10(-9) at the expense of a rate of read losses just in the order of 10(-6).

  5. System analysis with improved thermo-mechanical fuel rod models for modeling current and advanced LWR materials in accident scenarios

    NASA Astrophysics Data System (ADS)

    Porter, Ian Edward

    A nuclear reactor systems code has the ability to model the system response in an accident scenario based on known initial conditions at the onset of the transient. However, there has been a tendency for these codes to lack the detailed thermo-mechanical fuel rod response models needed for accurate prediction of fuel rod failure. This proposed work will couple today's most widely used steady-state (FRAPCON) and transient (FRAPTRAN) fuel rod models with a systems code TRACE for best-estimate modeling of system response in accident scenarios such as a loss of coolant accident (LOCA). In doing so, code modifications will be made to model gamma heating in LWRs during steady-state and accident conditions and to improve fuel rod thermal/mechanical analysis by allowing axial nodalization of burnup-dependent phenomena such as swelling, cladding creep and oxidation. With the ability to model both burnup-dependent parameters and transient fuel rod response, a fuel dispersal study will be conducted using a hypothetical accident scenario under both PWR and BWR conditions to determine the amount of fuel dispersed under varying conditions. Due to the fuel fragmentation size and internal rod pressure both being dependent on burnup, this analysis will be conducted at beginning, middle and end of cycle to examine the effects that cycle time can play on fuel rod failure and dispersal. Current fuel rod and system codes used by the Nuclear Regulatory Commission (NRC) are compilations of legacy codes with only commonly used light water reactor materials, Uranium Dioxide (UO2), Mixed Oxide (U/PuO 2) and zirconium alloys. However, the events at Fukushima Daiichi and Three Mile Island accident have shown the need for exploration into advanced materials possessing improved accident tolerance. This work looks to further modify the NRC codes to include silicon carbide (SiC), an advanced cladding material proposed by current DOE funded research on accident tolerant fuels (ATF). Several additional fuels will also be analyzed, including uranium nitride (UN), uranium carbide (UC) and uranium silicide (U3Si2). Focusing on the system response in an accident scenario, an emphasis is placed on the fracture mechanics of the ceramic cladding by design the fuel rods to eliminate pellet cladding mechanical interaction (PCMI). The time to failure and how much of the fuel in the reactor fails with an advanced fuel design will be analyzed and compared to the current UO2/Zircaloy design using a full scale reactor model.

  6. Area, speed and power measurements of FPGA-based complex orthogonal space-time block code channel encoders

    NASA Astrophysics Data System (ADS)

    Passas, Georgios; Freear, Steven; Fawcett, Darren

    2010-01-01

    Space-time coding (STC) is an important milestone in modern wireless communications. In this technique, more copies of the same signal are transmitted through different antennas (space) and different symbol periods (time), to improve the robustness of a wireless system by increasing its diversity gain. STCs are channel coding algorithms that can be readily implemented on a field programmable gate array (FPGA) device. This work provides some figures for the amount of required FPGA hardware resources, the speed that the algorithms can operate and the power consumption requirements of a space-time block code (STBC) encoder. Seven encoder very high-speed integrated circuit hardware description language (VHDL) designs have been coded, synthesised and tested. Each design realises a complex orthogonal space-time block code with a different transmission matrix. All VHDL designs are parameterisable in terms of sample precision. Precisions ranging from 4 bits to 32 bits have been synthesised. Alamouti's STBC encoder design [Alamouti, S.M. (1998), 'A Simple Transmit Diversity Technique for Wireless Communications', IEEE Journal on Selected Areas in Communications, 16:55-108.] proved to be the best trade-off, since it is on average 3.2 times smaller, 1.5 times faster and requires slightly less power than the next best trade-off in the comparison, which is a 3/4-rate full-diversity 3Tx-antenna STBC.

  7. Optical systems integrated modeling

    NASA Technical Reports Server (NTRS)

    Shannon, Robert R.; Laskin, Robert A.; Brewer, SI; Burrows, Chris; Epps, Harlan; Illingworth, Garth; Korsch, Dietrich; Levine, B. Martin; Mahajan, Vini; Rimmer, Chuck

    1992-01-01

    An integrated modeling capability that provides the tools by which entire optical systems and instruments can be simulated and optimized is a key technology development, applicable to all mission classes, especially astrophysics. Many of the future missions require optical systems that are physically much larger than anything flown before and yet must retain the characteristic sub-micron diffraction limited wavefront accuracy of their smaller precursors. It is no longer feasible to follow the path of 'cut and test' development; the sheer scale of these systems precludes many of the older techniques that rely upon ground evaluation of full size engineering units. The ability to accurately model (by computer) and optimize the entire flight system's integrated structural, thermal, and dynamic characteristics is essential. Two distinct integrated modeling capabilities are required. These are an initial design capability and a detailed design and optimization system. The content of an initial design package is shown. It would be a modular, workstation based code which allows preliminary integrated system analysis and trade studies to be carried out quickly by a single engineer or a small design team. A simple concept for a detailed design and optimization system is shown. This is a linkage of interface architecture that allows efficient interchange of information between existing large specialized optical, control, thermal, and structural design codes. The computing environment would be a network of large mainframe machines and its users would be project level design teams. More advanced concepts for detailed design systems would support interaction between modules and automated optimization of the entire system. Technology assessment and development plans for integrated package for initial design, interface development for detailed optimization, validation, and modeling research are presented.

  8. A Thermal Management Systems Model for the NASA GTX RBCC Concept

    NASA Technical Reports Server (NTRS)

    Traci, Richard M.; Farr, John L., Jr.; Laganelli, Tony; Walker, James (Technical Monitor)

    2002-01-01

    The Vehicle Integrated Thermal Management Analysis Code (VITMAC) was further developed to aid the analysis, design, and optimization of propellant and thermal management concepts for advanced propulsion systems. The computational tool is based on engineering level principles and models. A graphical user interface (GUI) provides a simple and straightforward method to assess and evaluate multiple concepts before undertaking more rigorous analysis of candidate systems. The tool incorporates the Chemical Equilibrium and Applications (CEA) program and the RJPA code to permit heat transfer analysis of both rocket and air breathing propulsion systems. Key parts of the code have been validated with experimental data. The tool was specifically tailored to analyze rocket-based combined-cycle (RBCC) propulsion systems being considered for space transportation applications. This report describes the computational tool and its development and verification for NASA GTX RBCC propulsion system applications.

  9. Cross-Layer Design for Space-Time coded MIMO Systems over Rice Fading Channel

    NASA Astrophysics Data System (ADS)

    Yu, Xiangbin; Zhou, Tingting; Liu, Xiaoshuai; Yin, Xin

    A cross-layer design (CLD) scheme for space-time coded MIMO systems over Rice fading channel is presented by combining adaptive modulation and automatic repeat request, and the corresponding system performance is investigated well. The fading gain switching thresholds subject to a target packet error rate (PER) and fixed power constraint are derived. According to these results, and using the generalized Marcum Q-function, the calculation formulae of the average spectrum efficiency (SE) and PER of the system with CLD are derived. As a result, closed-form expressions for average SE and PER are obtained. These expressions include some existing expressions in Rayleigh channel as special cases. With these expressions, the system performance in Rice fading channel is evaluated effectively. Numerical results verify the validity of the theoretical analysis. The results show that the system performance in Rice channel is effectively improved as Rice factor increases, and outperforms that in Rayleigh channel.

  10. Probabilistic structural analysis methods for select space propulsion system components

    NASA Technical Reports Server (NTRS)

    Millwater, H. R.; Cruse, T. A.

    1989-01-01

    The Probabilistic Structural Analysis Methods (PSAM) project developed at the Southwest Research Institute integrates state-of-the-art structural analysis techniques with probability theory for the design and analysis of complex large-scale engineering structures. An advanced efficient software system (NESSUS) capable of performing complex probabilistic analysis has been developed. NESSUS contains a number of software components to perform probabilistic analysis of structures. These components include: an expert system, a probabilistic finite element code, a probabilistic boundary element code and a fast probability integrator. The NESSUS software system is shown. An expert system is included to capture and utilize PSAM knowledge and experience. NESSUS/EXPERT is an interactive menu-driven expert system that provides information to assist in the use of the probabilistic finite element code NESSUS/FEM and the fast probability integrator (FPI). The expert system menu structure is summarized. The NESSUS system contains a state-of-the-art nonlinear probabilistic finite element code, NESSUS/FEM, to determine the structural response and sensitivities. A broad range of analysis capabilities and an extensive element library is present.

  11. Designing an efficient LT-code with unequal error protection for image transmission

    NASA Astrophysics Data System (ADS)

    S. Marques, F.; Schwartz, C.; Pinho, M. S.; Finamore, W. A.

    2015-10-01

    The use of images from earth observation satellites is spread over different applications, such as a car navigation systems and a disaster monitoring. In general, those images are captured by on board imaging devices and must be transmitted to the Earth using a communication system. Even though a high resolution image can produce a better Quality of Service, it leads to transmitters with high bit rate which require a large bandwidth and expend a large amount of energy. Therefore, it is very important to design efficient communication systems. From communication theory, it is well known that a source encoder is crucial in an efficient system. In a remote sensing satellite image transmission, this efficiency is achieved by using an image compressor, to reduce the amount of data which must be transmitted. The Consultative Committee for Space Data Systems (CCSDS), a multinational forum for the development of communications and data system standards for space flight, establishes a recommended standard for a data compression algorithm for images from space systems. Unfortunately, in the satellite communication channel, the transmitted signal is corrupted by the presence of noise, interference signals, etc. Therefore, the receiver of a digital communication system may fail to recover the transmitted bit. Actually, a channel code can be used to reduce the effect of this failure. In 2002, the Luby Transform code (LT-code) was introduced and it was shown that it was very efficient when the binary erasure channel model was used. Since the effect of the bit recovery failure depends on the position of the bit in the compressed image stream, in the last decade many e orts have been made to develop LT-code with unequal error protection. In 2012, Arslan et al. showed improvements when LT-codes with unequal error protection were used in images compressed by SPIHT algorithm. The techniques presented by Arslan et al. can be adapted to work with the algorithm for image compression recommended by CCSDS. In fact, to design a LT-code with an unequal error protection, the bit stream produced by the algorithm recommended by CCSDS must be partitioned in M disjoint sets of bits. Using the weighted approach, the LT-code produces M different failure probabilities for each set of bits, p1, ..., pM leading to a total probability of failure, p which is an average of p1, ..., pM. In general, the parameters of the LT-code with unequal error protection is chosen using a heuristic procedure. In this work, we analyze the problem of choosing the LT-code parameters to optimize two figure of merits: (a) the probability of achieving a minimum acceptable PSNR, and (b) the mean of PSNR, given that the minimum acceptable PSNR has been achieved. Given the rate-distortion curve achieved by CCSDS recommended algorithm, this work establishes a closed form of the mean of PSNR (given that the minimum acceptable PSNR has been achieved) as a function of p1, ..., pM. The main contribution of this work is the study of a criteria to select the parameters p1, ..., pM to optimize the performance of image transmission.

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

    NASA Technical Reports Server (NTRS)

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

    1996-01-01

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

  13. Automatic mathematical modeling for space application

    NASA Technical Reports Server (NTRS)

    Wang, Caroline K.

    1987-01-01

    A methodology for automatic mathematical modeling is described. The major objective is to create a very friendly environment for engineers to design, maintain and verify their model and also automatically convert the mathematical model into FORTRAN code for conventional computation. A demonstration program was designed for modeling the Space Shuttle Main Engine simulation mathematical model called Propulsion System Automatic Modeling (PSAM). PSAM provides a very friendly and well organized environment for engineers to build a knowledge base for base equations and general information. PSAM contains an initial set of component process elements for the Space Shuttle Main Engine simulation and a questionnaire that allows the engineer to answer a set of questions to specify a particular model. PSAM is then able to automatically generate the model and the FORTRAN code. A future goal is to download the FORTRAN code to the VAX/VMS system for conventional computation.

  14. Cognitive Code-Division Channelization

    DTIC Science & Technology

    2011-04-01

    22] G. N. Karystinos and D. A. Pados, “New bounds on the total squared correlation and optimum design of DS - CDMA binary signature sets,” IEEE Trans...Commun., vol. 51, pp. 48-51, Jan. 2003. [23] C. Ding, M. Golin, and T. Klve, “Meeting the Welch and Karystinos- Pados bounds on DS - CDMA binary...receiver pair coexisting with a primary code-division multiple-access ( CDMA ) system. Our objective is to find the optimum transmitting power and code

  15. NASA Glenn Steady-State Heat Pipe Code GLENHP: Compilation for 64- and 32-Bit Windows Platforms

    NASA Technical Reports Server (NTRS)

    Tower, Leonard K.; Geng, Steven M.

    2016-01-01

    A new version of the NASA Glenn Steady State Heat Pipe Code, designated "GLENHP," is introduced here. This represents an update to the disk operating system (DOS) version LERCHP reported in NASA/TM-2000-209807. The new code operates on 32- and 64-bit Windows-based platforms from within the 32-bit command prompt window. An additional evaporator boundary condition and other features are provided.

  16. Relational Database Design of a Shipboard Ammunition Inventory, Requisitioning, and Reporting System

    DTIC Science & Technology

    1990-06-01

    history of transactions effecting the status or quantity of that NI1N. Information on the current inventory balance is obtained from this section of...Number * Julian Date of Transaction * Activity Classification Code (ACC) * NALC * N1IN * Condition Code * Beginning Balance * Serial Number (if applicable...Ending Balance * Remarks As with the inventory information, ATR format varies with the type of control (Material Condition Code) applicable to that

  17. MINIVER upgrade for the AVID system. Volume 3: EXITS user's and input guide

    NASA Technical Reports Server (NTRS)

    Pond, J. E.; Schmitz, C. P.

    1983-01-01

    The successful design of thermal protection systems for vehicles operating in atmosphere and near-space environments requires accurate analyses of heating rate and temperature histories encountered along a trajectory. For preliminary design calculations, however, the requirement for accuracy must be tempered by the need for speed and versatility in computational tools used to determine thermal environments and structural thermal response. The MINIVER program was found to provide the proper balance between versatility, speed and accuracy for an aerothermal prediction tool. The advancement in computer aided design concepts at Langley Research Center (LaRC) in the past few years has made it desirable to incorporate the MINIVER program into the LaRC Advanced Vehicle Integrated Design, AVID, system. In order to effectively incorporate MINIVER into the AVID system, several changes to MINIVER were made. The thermal conduction options in MINIVER were removed and a new Explicit Interactive Thermal Structures (EXITS) code was developed. Many upgrades to the MINIVER code were made and a new Langley version of MINIVER called LANMIN was created.

  18. MINIVER upgrade for the AVID system. Volume 1: LANMIN user's manual

    NASA Technical Reports Server (NTRS)

    Engel, C. D.; Praharaj, S. C.

    1983-01-01

    The successful design of thermal protection systems for vehicles operating in atmosphere and near space environments requires accurate analyses of heating rate and temperature histories encountered along a trajectory. For preliminary design calculations, however, the requirement for accuracy must be tempered by the need for speed and versatility in computational tools used to determine thermal environments and structural thermal response. The MINIVER program has been found to provide the proper balance between versatility, speed and accuracy for an aerothermal prediction tool. The advancement in computer aided design concepts at Langley Research Center (LaRC) in the past few years has made it desirable to incorporate the MINIVER program into the LaRC Advanced Vehicle Integrated Design, AVID, system. In order to effectively incorporate MINIVER into the AVID system, several changes to MINIVER were made. The thermal conduction options in MINIVER were removed and a new Explicit Interactive Thermal Structures (EXITS) code was developed. Many upgrades to the MINIVER code were made and a new Langley version of MINIVER called LANMIN was created. The theoretical methods and subroutine functions used in LANMIN are described.

  19. Correlated Errors in the Surface Code

    NASA Astrophysics Data System (ADS)

    Lopez, Daniel; Mucciolo, E. R.; Novais, E.

    2012-02-01

    A milestone step into the development of quantum information technology would be the ability to design and operate a reliable quantum memory. The greatest obstacle to create such a device has been decoherence due to the unavoidable interaction between the quantum system and its environment. Quantum Error Correction is therefore an essential ingredient to any quantum computing information device. A great deal of attention has been given to surface codes, since it has very good scaling properties. In this seminar, we discuss the time evolution of a qubit encoded in the logical basis of a surface code. The system is interacting with a bosonic environment at zero temperature. Our results show how much spatial and time correlations can be detrimental to the efficiency of the code.

  20. Design of Cyber Attack Precursor Symptom Detection Algorithm through System Base Behavior Analysis and Memory Monitoring

    NASA Astrophysics Data System (ADS)

    Jung, Sungmo; Kim, Jong Hyun; Cagalaban, Giovanni; Lim, Ji-Hoon; Kim, Seoksoo

    More recently, botnet-based cyber attacks, including a spam mail or a DDos attack, have sharply increased, which poses a fatal threat to Internet services. At present, antivirus businesses make it top priority to detect malicious code in the shortest time possible (Lv.2), based on the graph showing a relation between spread of malicious code and time, which allows them to detect after malicious code occurs. Despite early detection, however, it is not possible to prevent malicious code from occurring. Thus, we have developed an algorithm that can detect precursor symptoms at Lv.1 to prevent a cyber attack using an evasion method of 'an executing environment aware attack' by analyzing system behaviors and monitoring memory.

  1. Implicit time-integration method for simultaneous solution of a coupled non-linear system

    NASA Astrophysics Data System (ADS)

    Watson, Justin Kyle

    Historically large physical problems have been divided into smaller problems based on the physics involved. This is no different in reactor safety analysis. The problem of analyzing a nuclear reactor for design basis accidents is performed by a handful of computer codes each solving a portion of the problem. The reactor thermal hydraulic response to an event is determined using a system code like TRAC RELAP Advanced Computational Engine (TRACE). The core power response to the same accident scenario is determined using a core physics code like Purdue Advanced Core Simulator (PARCS). Containment response to the reactor depressurization in a Loss Of Coolant Accident (LOCA) type event is calculated by a separate code. Sub-channel analysis is performed with yet another computer code. This is just a sample of the computer codes used to solve the overall problems of nuclear reactor design basis accidents. Traditionally each of these codes operates independently from each other using only the global results from one calculation as boundary conditions to another. Industry's drive to uprate power for reactors has motivated analysts to move from a conservative approach to design basis accident towards a best estimate method. To achieve a best estimate calculation efforts have been aimed at coupling the individual physics models to improve the accuracy of the analysis and reduce margins. The current coupling techniques are sequential in nature. During a calculation time-step data is passed between the two codes. The individual codes solve their portion of the calculation and converge to a solution before the calculation is allowed to proceed to the next time-step. This thesis presents a fully implicit method of simultaneous solving the neutron balance equations, heat conduction equations and the constitutive fluid dynamics equations. It discusses the problems involved in coupling different physics phenomena within multi-physics codes and presents a solution to these problems. The thesis also outlines the basic concepts behind the nodal balance equations, heat transfer equations and the thermal hydraulic equations, which will be coupled to form a fully implicit nonlinear system of equations. The coupling of separate physics models to solve a larger problem and improve accuracy and efficiency of a calculation is not a new idea, however implementing them in an implicit manner and solving the system simultaneously is. Also the application to reactor safety codes is new and has not be done with thermal hydraulics and neutronics codes on realistic applications in the past. The coupling technique described in this thesis is applicable to other similar coupled thermal hydraulic and core physics reactor safety codes. This technique is demonstrated using coupled input decks to show that the system is solved correctly and then verified by using two derivative test problems based on international benchmark problems the OECD/NRC Three mile Island (TMI) Main Steam Line Break (MSLB) problem (representative of pressurized water reactor analysis) and the OECD/NRC Peach Bottom (PB) Turbine Trip (TT) benchmark (representative of boiling water reactor analysis).

  2. Modeling Laboratory Astrophysics Experiments using the CRASH code

    NASA Astrophysics Data System (ADS)

    Trantham, Matthew; Drake, R. P.; Grosskopf, Michael; Bauerle, Matthew; Kruanz, Carolyn; Keiter, Paul; Malamud, Guy; Crash Team

    2013-10-01

    The understanding of high energy density systems can be advanced by laboratory astrophysics experiments. Computer simulations can assist in the design and analysis of these experiments. The Center for Radiative Shock Hydrodynamics (CRASH) at the University of Michigan developed a code that has been used to design and analyze high-energy-density experiments on OMEGA, NIF, and other large laser facilities. This Eulerian code uses block-adaptive mesh refinement (AMR) with implicit multigroup radiation transport and electron heat conduction. This poster/talk will demonstrate some of the experiments the CRASH code has helped design or analyze including: Radiative shocks experiments, Kelvin-Helmholtz experiments, Rayleigh-Taylor experiments, plasma sheet, and interacting jets experiments. This work is funded by the Predictive Sciences Academic Alliances Program in NNSA-ASC via grant DEFC52- 08NA28616, by the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, grant number DE-FG52-09NA29548, and by the National Laser User Facility Program, grant number DE-NA0000850.

  3. Weighing Evidence: The Design and Comparison of Probability Thought Experiments.

    DTIC Science & Technology

    1983-06-01

    ics and Other Logical Essays, R. G. Braithwaite (ed.), Routledge and Kegan Paul. Richardson, H. R., and Stone, L. D.: 1971, ’Operations analysis...Systems Department ONR Detachment Code 35 1030 East Green Street Naval Underwater Systems Center Pasadena, CA 91106 Newport, RI 02840 CDR James Offutt...Officer-in-Charge Human Factors Department ONR Detachment Code N-71 1030 East Green Street Naval Training Equipment Center Pasadena, CA 91106 Orlando

  4. Sparsening Filter Design for Iterative Soft-Input Soft-Output Detectors

    DTIC Science & Technology

    2012-02-29

    filter/detector structure. Since the BP detector itself is unaltered from [1], it can accommodate a system employing channel codes such as LDPC encoding...considered in [1], or can readily be extended to the MIMO case with, for example, space-time coding as in [2,8]. Since our focus is on the design of...simplex method of [15], since it was already available in Matlab , via the “fminsearch” function. 6 Cost surfaces To visualize the cost surfaces, consider

  5. Computational strategy for the solution of large strain nonlinear problems using the Wilkins explicit finite-difference approach

    NASA Technical Reports Server (NTRS)

    Hofmann, R.

    1980-01-01

    The STEALTH code system, which solves large strain, nonlinear continuum mechanics problems, was rigorously structured in both overall design and programming standards. The design is based on the theoretical elements of analysis while the programming standards attempt to establish a parallelism between physical theory, programming structure, and documentation. These features have made it easy to maintain, modify, and transport the codes. It has also guaranteed users a high level of quality control and quality assurance.

  6. High-speed inlet research program and supporting analysis

    NASA Technical Reports Server (NTRS)

    Coltrin, Robert E.

    1990-01-01

    The technology challenges faced by the high speed inlet designer are discussed by describing the considerations that went into the design of the Mach 5 research inlet. It is shown that the emerging three dimensional viscous computational fluid dynamics (CFD) flow codes, together with small scale experiments, can be used to guide larger scale full inlet systems research. Then, in turn, the results of the large scale research, if properly instrumented, can be used to validate or at least to calibrate the CFD codes.

  7. Aerodynamic Interference Due to MSL Reaction Control System

    NASA Technical Reports Server (NTRS)

    Dyakonov, Artem A.; Schoenenberger, Mark; Scallion, William I.; VanNorman, John W.; Novak, Luke A.; Tang, Chun Y.

    2009-01-01

    An investigation of effectiveness of the reaction control system (RCS) of Mars Science Laboratory (MSL) entry capsule during atmospheric flight has been conducted. The reason for the investigation is that MSL is designed to fly a lifting actively guided entry with hypersonic bank maneuvers, therefore an understanding of RCS effectiveness is required. In the course of the study several jet configurations were evaluated using Langley Aerothermal Upwind Relaxation Algorithm (LAURA) code, Data Parallel Line Relaxation (DPLR) code, Fully Unstructured 3D (FUN3D) code and an Overset Grid Flowsolver (OVERFLOW) code. Computations indicated that some of the proposed configurations might induce aero-RCS interactions, sufficient to impede and even overwhelm the intended control torques. It was found that the maximum potential for aero-RCS interference exists around peak dynamic pressure along the trajectory. Present analysis largely relies on computational methods. Ground testing, flight data and computational analyses are required to fully understand the problem. At the time of this writing some experimental work spanning range of Mach number 2.5 through 4.5 has been completed and used to establish preliminary levels of confidence for computations. As a result of the present work a final RCS configuration has been designed such as to minimize aero-interference effects and it is a design baseline for MSL entry capsule.

  8. The design of an adaptive predictive coder using a single-chip digital signal processor

    NASA Astrophysics Data System (ADS)

    Randolph, M. A.

    1985-01-01

    A speech coding processor architecture design study has been performed in which Texas Instruments TMS32010 has been selected from among three commercially available digital signal processing integrated circuits and evaluated in an implementation study of real-time Adaptive Predictive Coding (APC). The TMS32010 has been compared with AR&T Bell Laboratories DSP I and Nippon Electric Co. PD7720 and was found to be most suitable for a single chip implementation of APC. A preliminary design system based on TMS32010 has been performed, and several of the hardware and software design issues are discussed. Particular attention was paid to the design of an external memory controller which permits rapid sequential access of external RAM. As a result, it has been determined that a compact hardware implementation of the APC algorithm is feasible based of the TSM32010. Originator-supplied keywords include: vocoders, speech compression, adaptive predictive coding, digital signal processing microcomputers, speech processor architectures, and special purpose processor.

  9. The challenge of mapping between two medical coding systems.

    PubMed

    Wojcik, Barbara E; Stein, Catherine R; Devore, Raymond B; Hassell, L Harrison

    2006-11-01

    Deployable medical systems patient conditions (PCs) designate groups of patients with similar medical conditions and, therefore, similar treatment requirements. PCs are used by the U.S. military to estimate field medical resources needed in combat operations. Information associated with each of the 389 PCs is based on subject matter expert opinion, instead of direct derivation from standard medical codes. Currently, no mechanisms exist to tie current or historical medical data to PCs. Our study objective was to determine whether reliable conversion between PC codes and International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) diagnosis codes is possible. Data were analyzed for three professional coders assigning all applicable ICD-9-CM diagnosis codes to each PC code. Inter-rater reliability was measured by using Cohen's K statistic and percent agreement. Methods were developed to calculate kappa statistics when multiple responses could be selected from many possible categories. Overall, we found moderate support for the possibility of reliable conversion between PCs and ICD-9-CM diagnoses (mean kappa = 0.61). Current PCs should be modified into a system that is verifiable with real data.

  10. LOX/hydrocarbon auxiliary propulsion system study

    NASA Technical Reports Server (NTRS)

    Orton, G. F.; Mark, T. D.; Weber, D. D.

    1982-01-01

    Liquid oxygen/hydrocarbon propulsion systems applicable to a second generation orbiter OMS/RCS were compared, and major system/component options were evaluated. A large number of propellant combinations and system concepts were evaluated. The ground rules were defined in terms of candidate propellants, system/component design options, and design requirements. System and engine component math models were incorporated into existing computer codes for system evaluations. The detailed system evaluations and comparisons were performed to identify the recommended propellant combination and system approach.

  11. Design of efficient and simple interface testing equipment for opto-electric tracking system

    NASA Astrophysics Data System (ADS)

    Liu, Qiong; Deng, Chao; Tian, Jing; Mao, Yao

    2016-10-01

    Interface testing for opto-electric tracking system is one important work to assure system running performance, aiming to verify the design result of every electronic interface matching the communication protocols or not, by different levels. Opto-electric tracking system nowadays is more complicated, composed of many functional units. Usually, interface testing is executed between units manufactured completely, highly depending on unit design and manufacture progress as well as relative people. As a result, it always takes days or weeks, inefficiently. To solve the problem, this paper promotes an efficient and simple interface testing equipment for opto-electric tracking system, consisting of optional interface circuit card, processor and test program. The hardware cards provide matched hardware interface(s), easily offered from hardware engineer. Automatic code generation technique is imported, providing adaption to new communication protocols. Automatic acquiring items, automatic constructing code architecture and automatic encoding are used to form a new program quickly with adaption. After simple steps, a standard customized new interface testing equipment with matching test program and interface(s) is ready for a waiting-test system in minutes. The efficient and simple interface testing equipment for opto-electric tracking system has worked for many opto-electric tracking system to test entire or part interfaces, reducing test time from days to hours, greatly improving test efficiency, with high software quality and stability, without manual coding. Used as a common tool, the efficient and simple interface testing equipment for opto-electric tracking system promoted by this paper has changed traditional interface testing method and created much higher efficiency.

  12. Object-oriented approach for gas turbine engine simulation

    NASA Technical Reports Server (NTRS)

    Curlett, Brian P.; Felder, James L.

    1995-01-01

    An object-oriented gas turbine engine simulation program was developed. This program is a prototype for a more complete, commercial grade engine performance program now being proposed as part of the Numerical Propulsion System Simulator (NPSS). This report discusses architectural issues of this complex software system and the lessons learned from developing the prototype code. The prototype code is a fully functional, general purpose engine simulation program, however, only the component models necessary to model a transient compressor test rig have been written. The production system will be capable of steady state and transient modeling of almost any turbine engine configuration. Chief among the architectural considerations for this code was the framework in which the various software modules will interact. These modules include the equation solver, simulation code, data model, event handler, and user interface. Also documented in this report is the component based design of the simulation module and the inter-component communication paradigm. Object class hierarchies for some of the code modules are given.

  13. Intrasystem Analysis Program (IAP) code summaries

    NASA Astrophysics Data System (ADS)

    Dobmeier, J. J.; Drozd, A. L. S.; Surace, J. A.

    1983-05-01

    This report contains detailed descriptions and capabilities of the codes that comprise the Intrasystem Analysis Program. The four codes are: Intrasystem Electromagnetic Compatibility Analysis Program (IEMCAP), General Electromagnetic Model for the Analysis of Complex Systems (GEMACS), Nonlinear Circuit Analysis Program (NCAP), and Wire Coupling Prediction Models (WIRE). IEMCAP is used for computer-aided evaluation of electromagnetic compatibility (ECM) at all stages of an Air Force system's life cycle, applicable to aircraft, space/missile, and ground-based systems. GEMACS utilizes a Method of Moments (MOM) formalism with the Electric Field Integral Equation (EFIE) for the solution of electromagnetic radiation and scattering problems. The code employs both full matrix decomposition and Banded Matrix Iteration solution techniques and is expressly designed for large problems. NCAP is a circuit analysis code which uses the Volterra approach to solve for the transfer functions and node voltage of weakly nonlinear circuits. The Wire Programs deal with the Application of Multiconductor Transmission Line Theory to the Prediction of Cable Coupling for specific classes of problems.

  14. Overcoming the Challenges of Implementing a Multi-Mission Distributed Workflow System

    NASA Technical Reports Server (NTRS)

    Sayfi, Elias; Cheng, Cecilia; Lee, Hyun; Patel, Rajesh; Takagi, Atsuya; Yu, Dan

    2009-01-01

    A multi-mission approach to solving the same problems for various projects is enticing. However, the multi-mission approach leads to the need to develop a configurable, adaptable and distributed system to meet unique project requirements. That, in turn, leads to a set of challenges varying from handling synchronization issues to coming up with a smart design that allows the "unknowns" to be decided later. This paper discusses the challenges that the Multi-mission Automated Task Invocation Subsystem (MATIS) team has come up against while designing the distributed workflow system, as well as elaborates on the solutions that were implemented. The first is to design an easily adaptable system that requires no code changes as a result of configuration changes. The number of formal deliveries is often limited because each delivery costs time and money. Changes such as the sequence of programs being called, a change of a parameter value in the program that is being automated should not result in code changes or redelivery.

  15. 24 CFR 200.925b - Residential and institutional building code comparison items.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...); (6) Individual unit smoke detectors; (7) Building alarm systems; (8) Highrise criteria; (b) Light and...) Design live loads; (2) Design dead loads; (3) Snow loads; (4) Wind loads. (5) Earthquake loads (in...

  16. 24 CFR 200.925b - Residential and institutional building code comparison items.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...); (6) Individual unit smoke detectors; (7) Building alarm systems; (8) Highrise criteria; (b) Light and...) Design live loads; (2) Design dead loads; (3) Snow loads; (4) Wind loads. (5) Earthquake loads (in...

  17. 24 CFR 200.925b - Residential and institutional building code comparison items.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...); (6) Individual unit smoke detectors; (7) Building alarm systems; (8) Highrise criteria; (b) Light and...) Design live loads; (2) Design dead loads; (3) Snow loads; (4) Wind loads. (5) Earthquake loads (in...

  18. Flexible Generation of Kalman Filter Code

    NASA Technical Reports Server (NTRS)

    Richardson, Julian; Wilson, Edward

    2006-01-01

    Domain-specific program synthesis can automatically generate high quality code in complex domains from succinct specifications, but the range of programs which can be generated by a given synthesis system is typically narrow. Obtaining code which falls outside this narrow scope necessitates either 1) extension of the code generator, which is usually very expensive, or 2) manual modification of the generated code, which is often difficult and which must be redone whenever changes are made to the program specification. In this paper, we describe adaptations and extensions of the AUTOFILTER Kalman filter synthesis system which greatly extend the range of programs which can be generated. Users augment the input specification with a specification of code fragments and how those fragments should interleave with or replace parts of the synthesized filter. This allows users to generate a much wider range of programs without their needing to modify the synthesis system or edit generated code. We demonstrate the usefulness of the approach by applying it to the synthesis of a complex state estimator which combines code from several Kalman filters with user-specified code. The work described in this paper allows the complex design decisions necessary for real-world applications to be reflected in the synthesized code. When executed on simulated input data, the generated state estimator was found to produce comparable estimates to those produced by a handcoded estimator

  19. ITER's Tokamak Cooling Water System and the the Use of ASME Codes to Comply with French Regulations of Nuclear Pressure Equipment

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

    Berry, Jan; Ferrada, Juan J; Curd, Warren

    During inductive plasma operation of ITER, fusion power will reach 500 MW with an energy multiplication factor of 10. The heat will be transferred by the Tokamak Cooling Water System (TCWS) to the environment using the secondary cooling system. Plasma operations are inherently safe even under the most severe postulated accident condition a large, in-vessel break that results in a loss-of-coolant accident. A functioning cooling water system is not required to ensure safe shutdown. Even though ITER is inherently safe, TCWS equipment (e.g., heat exchangers, piping, pressurizers) are classified as safety important components. This is because the water is predictedmore » to contain low-levels of radionuclides (e.g., activated corrosion products, tritium) with activity levels high enough to require the design of components to be in accordance with French regulations for nuclear pressure equipment, i.e., the French Order dated 12 December 2005 (ESPN). ESPN has extended the practical application of the methodology established by the Pressure Equipment Directive (97/23/EC) to nuclear pressure equipment, under French Decree 99-1046 dated 13 December 1999, and Order dated 21 December 1999 (ESP). ASME codes and supplementary analyses (e.g., Failure Modes and Effects Analysis) will be used to demonstrate that the TCWS equipment meets these essential safety requirements. TCWS is being designed to provide not only cooling, with a capacity of approximately 1 GW energy removal, but also elevated temperature baking of first-wall/blanket, vacuum vessel, and divertor. Additional TCWS functions include chemical control of water, draining and drying for maintenance, and facilitation of leak detection/localization. The TCWS interfaces with the majority of ITER systems, including the secondary cooling system. U.S. ITER is responsible for design, engineering, and procurement of the TCWS with industry support from an Engineering Services Organization (ESO) (AREVA Federal Services, with support from Northrop Grumman, and OneCIS). ITER International Organization (ITER-IO) is responsible for design oversight and equipment installation in Cadarache, France. TCWS equipment will be fabricated using ASME design codes with quality assurance and oversight by an Agreed Notified Body (approved by the French regulator) that will ensure regulatory compliance. This paper describes the TCWS design and how U.S. ITER and fabricators will use ASME codes to comply with EU Directives and French Orders and Decrees.« less

  20. Discussion on LDPC Codes and Uplink Coding

    NASA Technical Reports Server (NTRS)

    Andrews, Ken; Divsalar, Dariush; Dolinar, Sam; Moision, Bruce; Hamkins, Jon; Pollara, Fabrizio

    2007-01-01

    This slide presentation reviews the progress that the workgroup on Low-Density Parity-Check (LDPC) for space link coding. The workgroup is tasked with developing and recommending new error correcting codes for near-Earth, Lunar, and deep space applications. Included in the presentation is a summary of the technical progress of the workgroup. Charts that show the LDPC decoder sensitivity to symbol scaling errors are reviewed, as well as a chart showing the performance of several frame synchronizer algorithms compared to that of some good codes and LDPC decoder tests at ESTL. Also reviewed is a study on Coding, Modulation, and Link Protocol (CMLP), and the recommended codes. A design for the Pseudo-Randomizer with LDPC Decoder and CRC is also reviewed. A chart that summarizes the three proposed coding systems is also presented.

  1. A Subsonic Aircraft Design Optimization With Neural Network and Regression Approximators

    NASA Technical Reports Server (NTRS)

    Patnaik, Surya N.; Coroneos, Rula M.; Guptill, James D.; Hopkins, Dale A.; Haller, William J.

    2004-01-01

    The Flight-Optimization-System (FLOPS) code encountered difficulty in analyzing a subsonic aircraft. The limitation made the design optimization problematic. The deficiencies have been alleviated through use of neural network and regression approximations. The insight gained from using the approximators is discussed in this paper. The FLOPS code is reviewed. Analysis models are developed and validated for each approximator. The regression method appears to hug the data points, while the neural network approximation follows a mean path. For an analysis cycle, the approximate model required milliseconds of central processing unit (CPU) time versus seconds by the FLOPS code. Performance of the approximators was satisfactory for aircraft analysis. A design optimization capability has been created by coupling the derived analyzers to the optimization test bed CometBoards. The approximators were efficient reanalysis tools in the aircraft design optimization. Instability encountered in the FLOPS analyzer was eliminated. The convergence characteristics were improved for the design optimization. The CPU time required to calculate the optimum solution, measured in hours with the FLOPS code was reduced to minutes with the neural network approximation and to seconds with the regression method. Generation of the approximators required the manipulation of a very large quantity of data. Design sensitivity with respect to the bounds of aircraft constraints is easily generated.

  2. Kim Jong IL and North Korea: The Leader and the System

    DTIC Science & Technology

    2006-03-01

    defined in Title 17, United States Code , section 101. As such, it is in the public domain, and under the provisions of Title 17, United States Code ...diplomat.35 Kim probably also had a major hand in designing the massive Nuremburg -style rally at the stadium that Albright witnessed the day before

  3. Recoding Numerics to Geometrics for Complex Discrimination Tasks; A Feasibility Study of Coding Strategy.

    ERIC Educational Resources Information Center

    Simpkins, John D.

    Processing complex multivariate information effectively when relational properties of information sub-groups are ambiguous is difficult for man and man-machine systems. However, the information processing task is made easier through code study, cybernetic planning, and accurate display mechanisms. An exploratory laboratory study designed for the…

  4. GLOBECOM '87 - Global Telecommunications Conference, Tokyo, Japan, Nov. 15-18, 1987, Conference Record. Volumes 1, 2, & 3

    NASA Astrophysics Data System (ADS)

    The present conference on global telecommunications discusses topics in the fields of Integrated Services Digital Network (ISDN) technology field trial planning and results to date, motion video coding, ISDN networking, future network communications security, flexible and intelligent voice/data networks, Asian and Pacific lightwave and radio systems, subscriber radio systems, the performance of distributed systems, signal processing theory, satellite communications modulation and coding, and terminals for the handicapped. Also discussed are knowledge-based technologies for communications systems, future satellite transmissions, high quality image services, novel digital signal processors, broadband network access interface, traffic engineering for ISDN design and planning, telecommunications software, coherent optical communications, multimedia terminal systems, advanced speed coding, portable and mobile radio communications, multi-Gbit/second lightwave transmission systems, enhanced capability digital terminals, communications network reliability, advanced antimultipath fading techniques, undersea lightwave transmission, image coding, modulation and synchronization, adaptive signal processing, integrated optical devices, VLSI technologies for ISDN, field performance of packet switching, CSMA protocols, optical transport system architectures for broadband ISDN, mobile satellite communications, indoor wireless communication, echo cancellation in communications, and distributed network algorithms.

  5. Clean air program : design guidelines for bus transit systems using compressed natural gas as an alternative fuel

    DOT National Transportation Integrated Search

    1996-06-01

    This report documents design guidelines for the safe use of Compressed Natural Gas (CNG). The report is designed to provide guidance, information on safe industry practices, applicable national codes and standards, and reference data that transit age...

  6. The Development of a Portable Hard Disk Encryption/Decryption System with a MEMS Coded Lock.

    PubMed

    Zhang, Weiping; Chen, Wenyuan; Tang, Jian; Xu, Peng; Li, Yibin; Li, Shengyong

    2009-01-01

    In this paper, a novel portable hard-disk encryption/decryption system with a MEMS coded lock is presented, which can authenticate the user and provide the key for the AES encryption/decryption module. The portable hard-disk encryption/decryption system is composed of the authentication module, the USB portable hard-disk interface card, the ATA protocol command decoder module, the data encryption/decryption module, the cipher key management module, the MEMS coded lock controlling circuit module, the MEMS coded lock and the hard disk. The ATA protocol circuit, the MEMS control circuit and AES encryption/decryption circuit are designed and realized by FPGA(Field Programmable Gate Array). The MEMS coded lock with two couplers and two groups of counter-meshing-gears (CMGs) are fabricated by a LIGA-like process and precision engineering method. The whole prototype was fabricated and tested. The test results show that the user's password could be correctly discriminated by the MEMS coded lock, and the AES encryption module could get the key from the MEMS coded lock. Moreover, the data in the hard-disk could be encrypted or decrypted, and the read-write speed of the dataflow could reach 17 MB/s in Ultra DMA mode.

  7. System architectures for telerobotic research

    NASA Technical Reports Server (NTRS)

    Harrison, F. Wallace

    1989-01-01

    Several activities are performed related to the definition and creation of telerobotic systems. The effort and investment required to create architectures for these complex systems can be enormous; however, the magnitude of process can be reduced if structured design techniques are applied. A number of informal methodologies supporting certain aspects of the design process are available. More recently, prototypes of integrated tools supporting all phases of system design from requirements analysis to code generation and hardware layout have begun to appear. Activities related to system architecture of telerobots are described, including current activities which are designed to provide a methodology for the comparison and quantitative analysis of alternative system architectures.

  8. Validation of CFD/Heat Transfer Software for Turbine Blade Analysis

    NASA Technical Reports Server (NTRS)

    Kiefer, Walter D.

    2004-01-01

    I am an intern in the Turbine Branch of the Turbomachinery and Propulsion Systems Division. The division is primarily concerned with experimental and computational methods of calculating heat transfer effects of turbine blades during operation in jet engines and land-based power systems. These include modeling flow in internal cooling passages and film cooling, as well as calculating heat flux and peak temperatures to ensure safe and efficient operation. The branch is research-oriented, emphasizing the development of tools that may be used by gas turbine designers in industry. The branch has been developing a computational fluid dynamics (CFD) and heat transfer code called GlennHT to achieve the computational end of this analysis. The code was originally written in FORTRAN 77 and run on Silicon Graphics machines. However the code has been rewritten and compiled in FORTRAN 90 to take advantage of more modem computer memory systems. In addition the branch has made a switch in system architectures from SGI's to Linux PC's. The newly modified code therefore needs to be tested and validated. This is the primary goal of my internship. To validate the GlennHT code, it must be run using benchmark fluid mechanics and heat transfer test cases, for which there are either analytical solutions or widely accepted experimental data. From the solutions generated by the code, comparisons can be made to the correct solutions to establish the accuracy of the code. To design and create these test cases, there are many steps and programs that must be used. Before a test case can be run, pre-processing steps must be accomplished. These include generating a grid to describe the geometry, using a software package called GridPro. Also various files required by the GlennHT code must be created including a boundary condition file, a file for multi-processor computing, and a file to describe problem and algorithm parameters. A good deal of this internship will be to become familiar with these programs and the structure of the GlennHT code. Additional information is included in the original extended abstract.

  9. FY2017 Updates to the SAS4A/SASSYS-1 Safety Analysis Code

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

    Fanning, T. H.

    The SAS4A/SASSYS-1 safety analysis software is used to perform deterministic analysis of anticipated events as well as design-basis and beyond-design-basis accidents for advanced fast reactors. It plays a central role in the analysis of U.S. DOE conceptual designs, proposed test and demonstration reactors, and in domestic and international collaborations. This report summarizes the code development activities that have taken place during FY2017. Extensions to the void and cladding reactivity feedback models have been implemented, and Control System capabilities have been improved through a new virtual data acquisition system for plant state variables and an additional Block Signal for a variablemore » lag compensator to represent reactivity feedback for novel shutdown devices. Current code development and maintenance needs are also summarized in three key areas: software quality assurance, modeling improvements, and maintenance of related tools. With ongoing support, SAS4A/SASSYS-1 can continue to fulfill its growing role in fast reactor safety analysis and help solidify DOE’s leadership role in fast reactor safety both domestically and in international collaborations.« less

  10. System Simulation of Nuclear Power Plant by Coupling RELAP5 and Matlab/Simulink

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

    Meng Lin; Dong Hou; Zhihong Xu

    2006-07-01

    Since RELAP5 code has general and advanced features in thermal-hydraulic computation, it has been widely used in transient and accident safety analysis, experiment planning analysis, and system simulation, etc. So we wish to design, analyze, verify a new Instrumentation And Control (I and C) system of Nuclear Power Plant (NPP) based on the best-estimated code, and even develop our engineering simulator. But because of limited function of simulating control and protection system in RELAP5, it is necessary to expand the function for high efficient, accurate, flexible design and simulation of I and C system. Matlab/Simulink, a scientific computation software, justmore » can compensate the limitation, which is a powerful tool in research and simulation of plant process control. The software is selected as I and C part to be coupled with RELAP5 code to realize system simulation of NPPs. There are two key techniques to be solved. One is the dynamic data exchange, by which Matlab/Simulink receives plant parameters and returns control results. Database is used to communicate the two codes. Accordingly, Dynamic Link Library (DLL) is applied to link database in RELAP5, while DLL and S-Function is applied in Matlab/Simulink. The other problem is synchronization between the two codes for ensuring consistency in global simulation time. Because Matlab/Simulink always computes faster than RELAP5, the simulation time is sent by RELAP5 and received by Matlab/Simulink. A time control subroutine is added into the simulation procedure of Matlab/Simulink to control its simulation advancement. Through these ways, Matlab/Simulink is dynamically coupled with RELAP5. Thus, in Matlab/Simulink, we can freely design control and protection logic of NPPs and test it with best-estimated plant model feedback. A test will be shown to illuminate that results of coupling calculation are nearly the same with one of single RELAP5 with control logic. In practice, a real Pressurized Water Reactor (PWR) is modeled by RELAP5 code, and its main control and protection system is duplicated by Matlab/Simulink. Some steady states and transients are calculated under control of these I and C systems, and the results are compared with the plant test curves. The application showed that it can do exact system simulation of NPPs by coupling RELAP5 and Matlab/Simulink. This paper will mainly focus on the coupling method, plant thermal-hydraulic model, main control logics, test and application results. (authors)« less

  11. Towards a supported common NEAMS software stack

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

    Cormac Garvey

    2012-04-01

    The NEAMS IPSC's are developing multidimensional, multiphysics, multiscale simulation codes based on first principles that will be capable of predicting all aspects of current and future nuclear reactor systems. These new breeds of simulation codes will include rigorous verification, validation and uncertainty quantification checks to quantify the accuracy and quality of the simulation results. The resulting NEAMS IPSC simulation codes will be an invaluable tool in designing the next generation of Nuclear Reactors and also contribute to a more speedy process in the acquisition of licenses from the NRC for new Reactor designs. Due to the high resolution of themore » models, the complexity of the physics and the added computational resources to quantify the accuracy/quality of the results, the NEAMS IPSC codes will require large HPC resources to carry out the production simulation runs.« less

  12. Computer Simulation of the VASIMR Engine

    NASA Technical Reports Server (NTRS)

    Garrison, David

    2005-01-01

    The goal of this project is to develop a magneto-hydrodynamic (MHD) computer code for simulation of the VASIMR engine. This code is designed be easy to modify and use. We achieve this using the Cactus framework, a system originally developed for research in numerical relativity. Since its release, Cactus has become an extremely powerful and flexible open source framework. The development of the code will be done in stages, starting with a basic fluid dynamic simulation and working towards a more complex MHD code. Once developed, this code can be used by students and researchers in order to further test and improve the VASIMR engine.

  13. Optimization of wavefront coding imaging system using heuristic algorithms

    NASA Astrophysics Data System (ADS)

    González-Amador, E.; Padilla-Vivanco, A.; Toxqui-Quitl, C.; Zermeño-Loreto, O.

    2017-08-01

    Wavefront Coding (WFC) systems make use of an aspheric Phase-Mask (PM) and digital image processing to extend the Depth of Field (EDoF) of computational imaging systems. For years, several kinds of PM have been designed to produce a point spread function (PSF) near defocus-invariant. In this paper, the optimization of the phase deviation parameter is done by means of genetic algorithms (GAs). In this, the merit function minimizes the mean square error (MSE) between the diffraction limited Modulated Transfer Function (MTF) and the MTF of the system that is wavefront coded with different misfocus. WFC systems were simulated using the cubic, trefoil, and 4 Zernike polynomials phase-masks. Numerical results show defocus invariance aberration in all cases. Nevertheless, the best results are obtained by using the trefoil phase-mask, because the decoded image is almost free of artifacts.

  14. Two-Dimensional Optical CDMA System Parameters Limitations for Wavelength Hopping/Time-Spreading Scheme based on Simulation Experiment

    NASA Astrophysics Data System (ADS)

    Kandouci, Chahinaz; Djebbari, Ali

    2018-04-01

    A new family of two-dimensional optical hybrid code which employs zero cross-correlation (ZCC) codes, constructed by the balanced incomplete block design BIBD, as both time-spreading and wavelength hopping patterns are used in this paper. The obtained codes have both off-peak autocorrelation and cross-correlation values respectively equal to zero and unity. The work in this paper is a computer experiment performed using Optisystem 9.0 software program as a simulator to determine the wavelength hopping/time spreading (WH/TS) OCDMA system performances limitations. Five system parameters were considered in this work: the optical fiber length (transmission distance), the bitrate, the chip spacing and the transmitted power. This paper shows for what sufficient system performance parameters (BER≤10-9, Q≥6) the system can stand for.

  15. Application of IPAD to missile design

    NASA Technical Reports Server (NTRS)

    Santa, J. E.; Whiting, T. R.

    1974-01-01

    The application of an integrated program for aerospace-vehicle design (IPAD) to the design of a tactical missile is examined. The feasibility of modifying a proposed IPAD system for aircraft design work for use in missile design is evaluated. The tasks, cost, and schedule for the modification are presented. The basic engineering design process is described, explaining how missile design is achieved through iteration of six logical problem solving functions throughout the system studies, preliminary design, and detailed design phases of a new product. Existing computer codes used in various engineering disciplines are evaluated for their applicability to IPAD in missile design.

  16. Automated software development workstation

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Engineering software development was automated using an expert system (rule-based) approach. The use of this technology offers benefits not available from current software development and maintenance methodologies. A workstation was built with a library or program data base with methods for browsing the designs stored; a system for graphical specification of designs including a capability for hierarchical refinement and definition in a graphical design system; and an automated code generation capability in FORTRAN. The workstation was then used in a demonstration with examples from an attitude control subsystem design for the space station. Documentation and recommendations are presented.

  17. Suppression criteria of parasitic mode oscillations in a gyrotron beam tunnel

    NASA Astrophysics Data System (ADS)

    Kumar, Nitin; Singh, Udaybir; Singh, T. P.; Sinha, A. K.

    2011-02-01

    This paper presents the design criteria of the parasitic mode oscillations suppression for a periodic, ceramic, and copper loaded gyrotron beam tunnel. In such a type of beam tunnel, the suppression of parasitic mode oscillations is an important design problem. A method of beam-wave coupling coefficient and its mathematical formulation are presented. The developed design criteria are used in the beam tunnel design of a 42 GHz gyrotron to be developed for the Indian TOKAMAK system. The role of the thickness and the radius of the beam tunnel copper rings to obtain the developed design criteria are also discussed. The commercially available electromagnetic code CST and the electron trajectory code EGUN are used for the simulations.

  18. Dissemination and support of ARGUS for accelerator applications

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

    Not Available

    The ARGUS code is a three-dimensional code system for simulating for interactions between charged particles, electric and magnetic fields, and complex structure. It is a system of modules that share common utilities for grid and structure input, data handling, memory management, diagnostics, and other specialized functions. The code includes the fields due to the space charge and current density of the particles to achieve a self-consistent treatment of the particle dynamics. The physic modules in ARGUS include three-dimensional field solvers for electrostatics and electromagnetics, a three-dimensional electromagnetic frequency-domain module, a full particle-in-cell (PIC) simulation module, and a steady-state PIC model.more » These are described in the Appendix to this report. This project has a primary mission of developing the capabilities of ARGUS in accelerator modeling of release to the accelerator design community. Five major activities are being pursued in parallel during the first year of the project. To improve the code and/or add new modules that provide capabilities needed for accelerator design. To produce a User's Guide that documents the use of the code for all users. To release the code and the User's Guide to accelerator laboratories for their own use, and to obtain feed-back from the. To build an interactive user interface for setting up ARGUS calculations. To explore the use of ARGUS on high-power workstation platforms.« less

  19. A grid generation system for multi-disciplinary design optimization

    NASA Technical Reports Server (NTRS)

    Jones, William T.; Samareh-Abolhassani, Jamshid

    1995-01-01

    A general multi-block three-dimensional volume grid generator is presented which is suitable for Multi-Disciplinary Design Optimization. The code is timely, robust, highly automated, and written in ANSI 'C' for platform independence. Algebraic techniques are used to generate and/or modify block face and volume grids to reflect geometric changes resulting from design optimization. Volume grids are generated/modified in a batch environment and controlled via an ASCII user input deck. This allows the code to be incorporated directly into the design loop. Generated volume grids are presented for a High Speed Civil Transport (HSCT) Wing/Body geometry as well a complex HSCT configuration including horizontal and vertical tails, engine nacelles and pylons, and canard surfaces.

  20. Two-bit trinary full adder design based on restricted signed-digit numbers

    NASA Astrophysics Data System (ADS)

    Ahmed, J. U.; Awwal, A. A. S.; Karim, M. A.

    1994-08-01

    A 2-bit trinary full adder using a restricted set of a modified signed-digit trinary numeric system is designed. When cascaded together to design a multi-bit adder machine, the resulting system is able to operate at a speed independent of the size of the operands. An optical non-holographic content addressable memory based on binary coded arithmetic is considered for implementing the proposed adder.

  1. Adaptive Digital Signature Design and Short-Data-Record Adaptive Filtering

    DTIC Science & Technology

    2008-04-01

    rate BPSK binary phase shift keying CA − CFAR cell averaging− constant false alarm rate CDMA code − division multiple − access CFAR constant false...Cotae, “Spreading sequence design for multiple cell synchronous DS-CDMA systems under total weighted squared correlation criterion,” EURASIP Journal...415-428, Mar. 2002. [6] P. Cotae, “Spreading sequence design for multiple cell synchronous DS-CDMA systems under total weighted squared correlation

  2. More About Vector Adaptive/Predictive Coding Of Speech

    NASA Technical Reports Server (NTRS)

    Jedrey, Thomas C.; Gersho, Allen

    1992-01-01

    Report presents additional information about digital speech-encoding and -decoding system described in "Vector Adaptive/Predictive Encoding of Speech" (NPO-17230). Summarizes development of vector adaptive/predictive coding (VAPC) system and describes basic functions of algorithm. Describes refinements introduced enabling receiver to cope with errors. VAPC algorithm implemented in integrated-circuit coding/decoding processors (codecs). VAPC and other codecs tested under variety of operating conditions. Tests designed to reveal effects of various background quiet and noisy environments and of poor telephone equipment. VAPC found competitive with and, in some respects, superior to other 4.8-kb/s codecs and other codecs of similar complexity.

  3. Design Fragments

    DTIC Science & Technology

    2007-04-19

    define the patterns and are better at analyzing behavior. SPQR (System for Pattern Query and Recognition) [18, 58] can recognize pattern vari- ants...Stotts. SPQR : Flexible automated design pattern extraction from source code. ase, 00:215, 2003. ISSN 1527-1366. doi: http://doi.ieeecomputersociety. org

  4. Propellant Chemistry for CFD Applications

    NASA Technical Reports Server (NTRS)

    Farmer, R. C.; Anderson, P. G.; Cheng, Gary C.

    1996-01-01

    Current concepts for reusable launch vehicle design have created renewed interest in the use of RP-1 fuels for high pressure and tri-propellant propulsion systems. Such designs require the use of an analytical technology that accurately accounts for the effects of real fluid properties, combustion of large hydrocarbon fuel modules, and the possibility of soot formation. These effects are inadequately treated in current computational fluid dynamic (CFD) codes used for propulsion system analyses. The objective of this investigation is to provide an accurate analytical description of hydrocarbon combustion thermodynamics and kinetics that is sufficiently computationally efficient to be a practical design tool when used with CFD codes such as the FDNS code. A rigorous description of real fluid properties for RP-1 and its combustion products will be derived from the literature and from experiments conducted in this investigation. Upon the establishment of such a description, the fluid description will be simplified by using the minimum of empiricism necessary to maintain accurate combustion analyses and including such empirical models into an appropriate CFD code. An additional benefit of this approach is that the real fluid properties analysis simplifies the introduction of the effects of droplet sprays into the combustion model. Typical species compositions of RP-1 have been identified, surrogate fuels have been established for analyses, and combustion and sooting reaction kinetics models have been developed. Methods for predicting the necessary real fluid properties have been developed and essential experiments have been designed. Verification studies are in progress, and preliminary results from these studies will be presented. The approach has been determined to be feasible, and upon its completion the required methodology for accurate performance and heat transfer CFD analyses for high pressure, tri-propellant propulsion systems will be available.

  5. Design criteria for noncoherent Gaussian channels with MFSK signaling and coding

    NASA Technical Reports Server (NTRS)

    Butman, S. A.; Levitt, B. K.; Bar-David, I.; Lyon, R. F.; Klass, M. J.

    1976-01-01

    This paper presents data and criteria to assess and guide the design of modems for coded noncoherent communication systems subject to practical system constraints of power, bandwidth, noise spectral density, coherence time, and number of orthogonal signals M. Three basic receiver types are analyzed for the noncoherent multifrequency-shift keying (MFSK) additive white Gaussian noise channel: hard decision, unquantized (optimum), and quantized (soft decision). Channel capacity and computational cutoff rate are computed for each type and presented as functions of the predetection signal-to-noise ratio and the number of orthogonal signals. This relates the channel constraints of power, bandwidth, coherence time, and noise power to the optimum choice of signal duration and signal number.

  6. Reliability model of a monopropellant auxiliary propulsion system

    NASA Technical Reports Server (NTRS)

    Greenberg, J. S.

    1971-01-01

    A mathematical model and associated computer code has been developed which computes the reliability of a monopropellant blowdown hydrazine spacecraft auxiliary propulsion system as a function of time. The propulsion system is used to adjust or modify the spacecraft orbit over an extended period of time. The multiple orbit corrections are the multiple objectives which the auxiliary propulsion system is designed to achieve. Thus the reliability model computes the probability of successfully accomplishing each of the desired orbit corrections. To accomplish this, the reliability model interfaces with a computer code that models the performance of a blowdown (unregulated) monopropellant auxiliary propulsion system. The computer code acts as a performance model and as such gives an accurate time history of the system operating parameters. The basic timing and status information is passed on to and utilized by the reliability model which establishes the probability of successfully accomplishing the orbit corrections.

  7. Requirements to Design to Code: Towards a Fully Formal Approach to Automatic Code Generation

    NASA Technical Reports Server (NTRS)

    Hinchey, Michael G.; Rash, James L.; Rouff, Christopher A.

    2004-01-01

    A general-purpose method to mechanically transform system requirements into a provably equivalent model has yet to appear. Such a method represents a necessary step toward high-dependability system engineering for numerous possible application domains, including sensor networks and autonomous systems. Currently available tools and methods that start with a formal model of a system and mechanically produce a provably equivalent implementation are valuable but not sufficient. The gap that current tools and methods leave unfilled is that their formal models cannot be proven to be equivalent to the system requirements as originated by the customer. For the classes of systems whose behavior can be described as a finite (but significant) set of scenarios, we offer a method for mechanically transforming requirements (expressed in restricted natural language, or in other appropriate graphical notations) into a provably equivalent formal model that can be used as the basis for code generation and other transformations.

  8. Past, Present and Future Advanced ECLS Systems for Human Exploration of Space

    NASA Technical Reports Server (NTRS)

    Mitchell, Kenny

    2004-01-01

    This paper will review the historical record of NASA's regenerative life support systems flight hardware with emphasis on the complexity of spiral development of technology as related to the International Space Station program. A brief summary of what constitutes ECLSS designs for human habitation will be included and will provide illustrations of the complex system/system integration issues. The new technology areas which need to be addressed in our future Code T initiatives will be highlighted. The development status of the current regenerative ECLSS for Space Station will be provided for the Oxygen Generation System and the Water Recovery System. In addition, the NASA is planning to augment the existing ISS capability with a new technology development effort by Code U/Code T for CO2 reduction (Sabatier Reactor). This latest ISS spiral development activity will be highlighted in this paper.

  9. Automated drafting system uses computer techniques

    NASA Technical Reports Server (NTRS)

    Millenson, D. H.

    1966-01-01

    Automated drafting system produces schematic and block diagrams from the design engineers freehand sketches. This system codes conventional drafting symbols and their coordinate locations on standard size drawings for entry on tapes that are used to drive a high speed photocomposition machine.

  10. Examination of Airborne FDEM System Attributes for UXO Mapping and Detection

    DTIC Science & Technology

    2009-11-01

    quadrature output should only occur when there is a distortion in the transmitter waveform signal that correlates with the quadrature part of the...suggested that the S/N performance of the quadrature output of the two FDEM designs would be similar to the observed S/N of TEM systems, though...the semi-airborne configuration. We propose to extend the current SAIC codes to address this need, and to perform additional modeling using codes

  11. Working Group on Ice Forces on Structures. A State-of-the-Art Report.

    DTIC Science & Technology

    1980-06-01

    observed in Soviet Design Codes, but the randomness of ice properties is not directly observed anywhere. 3.3 Contact system The mode of ice failure against...ups .............. o..........................90 2.133 Factors limiting ice ride-up ..................... o............91 2.134 Procedures for designing ...o................................110 3.3 Contact system .................................................. 115 3.4 Damping

  12. Application of binomial and multinomial probability statistics to the sampling design process of a global grain tracing and recall system

    USDA-ARS?s Scientific Manuscript database

    Small, coded, pill-sized tracers embedded in grain are proposed as a method for grain traceability. A sampling process for a grain traceability system was designed and investigated by applying probability statistics using a science-based sampling approach to collect an adequate number of tracers fo...

  13. Circuit Design Approaches for Implementation of a Subtrellis IC for a Reed-Muller Subcode

    NASA Technical Reports Server (NTRS)

    Lin, Shu; Uehara, Gregory T.; Nakamura, Eric B.; Chu, Cecilia W. P.

    1996-01-01

    In his research, we have proposed the (64, 40, 8) subcode of the third-order Reed-Muller (RM) code to NASA for high-speed satellite communications. This RM subcode can be used either alone or as an inner code of a concatenated coding system with the NASA standard (255, 233, 33) Reed-Solomon (RS) code as the outer code to achieve high performance (or low bit-error rate) with reduced decoding complexity. It can also be used as a component code in a multilevel bandwidth efficient coded modulation system to achieve reliable bandwidth efficient data transmission. This report will summarize the key progress we have made toward achieving our eventual goal of implementing a decoder system based upon this code. In the first phase of study, we investigated the complexities of various sectionalized trellis diagrams for the proposed (64, 40, 8) RM subcode. We found a specific 8-trellis diagram for this code which requires the least decoding complexity with a high possibility of achieving a decoding speed of 600 M bits per second(Mbps). The combination of a large number of states and a high data rate will be made possible due to the utilization of a high degree of parallelism throughout the architecture. This trellis diagram will be presented and briefly described. In the second phase of study which was carried out through the past year, we investigated circuit architectures to determine the feasibility of VLSI implementation of a high- speed Viterbi decoder based on this 8-section trellis diagram. We began to examine specific design and implementation approaches to implement a fully custom integrated circuit (IC) which will be a key building block for a decoder system implementation. The key results will be presented in this report. This report will be divided into three primary sections. First, we will briefly describe the system block diagram in which the proposed decoder is assumed to be operating and present some of the key architectural approaches being used to implement the system at high speed. Second, we will describe details of the 8-trellis diagram we found to best meet the trade-offs between chip and overall system complexity. The chosen approach implements the trellis for the (64, 40, 8) RM subcode with 32 independent sub-trellises. And third, we will describe results of our feasibility study on the implementation of such an IC chip in CMOS technology to implement one of these subtrellises.

  14. Circuit Design Approaches for Implementation of a Subtrellis IC for a Reed-Muller Subcode

    NASA Technical Reports Server (NTRS)

    Lin, Shu; Uehara, Gregory T.; Nakamura, Eric B.; Chu, Cecilia W. P.

    1996-01-01

    In this research, we have proposed the (64, 40, 8) subcode of the third-order Reed-Muller (RM) code to NASA for high-speed satellite communications. This RM subcode can be used either alone or as an inner code of a concatenated coding system with the NASA standard (255, 233, 33) Reed-Solomon (RS) code as the outer code to achieve high performance (or low bit-error rate) with reduced decoding complexity. It can also be used as a component code in a multilevel bandwidth efficient coded modulation system to achieve reliable bandwidth efficient data transmission. This report will summarize the key progress we have made toward achieving our eventual goal of implementing a decoder system based upon this code. In the first phase of study, we investigated the complexities of various sectionalized trellis diagrams for the proposed (64, 40, 8) RM subcode. We found a specific 8-trellis diagram for this code which requires the least decoding complexity with a high possibility of achieving a decoding speed of 600 M bits per second (Mbps). The combination of a large number of states and a high data rate will be made possible due to the utilization of a high degree of parallelism throughout the architecture. This trellis diagram will be presented and briefly described. In the second phase of study which was carried out through the past year, we investigated circuit architectures to determine the feasibility of VLSI implementation of a high-speed Viterbi decoder based on this 8-section trellis diagram. We began to examine specific design and implementation approaches to implement a fully custom integrated circuit (IC) which will be a key building block for a decoder system implementation. The key results will be presented in this report. This report will be divided into three primary sections. First, we will briefly describe the system block diagram in which the proposed decoder is assumed to be operating and present some of the key architectural approaches being used to implement the system at high speed. Second, we will describe details of the 8-trellis diagram we found to best meet the trade-offs between chip and overall system complexity. The chosen approach implements the trellis for the (64, 40, 8) RM subcode with 32 independent sub-trellises. And third, we will describe results of our feasibility study on the implementation of such an IC chip in CMOS technology to implement one of these subtrellises.

  15. Object-oriented design and programming in medical decision support.

    PubMed

    Heathfield, H; Armstrong, J; Kirkham, N

    1991-12-01

    The concept of object-oriented design and programming has recently received a great deal of attention from the software engineering community. This paper highlights the realisable benefits of using the object-oriented approach in the design and development of clinical decision support systems. These systems seek to build a computational model of some problem domain and therefore tend to be exploratory in nature. Conventional procedural design techniques do not support either the process of model building or rapid prototyping. The central concepts of the object-oriented paradigm are introduced, namely encapsulation, inheritance and polymorphism, and their use illustrated in a case study, taken from the domain of breast histopathology. In particular, the dual roles of inheritance in object-oriented programming are examined, i.e., inheritance as a conceptual modelling tool and inheritance as a code reuse mechanism. It is argued that the use of the former is not entirely intuitive and may be difficult to incorporate into the design process. However, inheritance as a means of optimising code reuse offers substantial technical benefits.

  16. A pseudo-noise transponder design for low data rate users of the tracking and data relay satellite system

    NASA Technical Reports Server (NTRS)

    Birch, J. N.

    1971-01-01

    A compromise optimum design for the low data rate users of the Tracking and Data Relay Satellite System (TDRSS) is presented. Design goals for the TDRSS are employed in this report to arrive at the transponder design. Multipath, R.F.I., antenna pattern anomolies, other user signals, and other definable degrading factors are included as trade-off parameters in the design. Synchronization, emergency voice, user stabilization, polarization diversity and error control coding are also considered and their impact on the transponder design is evaluated.

  17. Thermal-hydraulics Analysis of a Radioisotope-powered Mars Hopper Propulsion System

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

    Robert C. O'Brien; Andrew C. Klein; William T. Taitano

    Thermal-hydraulics analyses results produced using a combined suite of computational design and analysis codes are presented for the preliminary design of a concept Radioisotope Thermal Rocket (RTR) propulsion system. Modeling of the transient heating and steady state temperatures of the system is presented. Simulation results for propellant blow down during impulsive operation are also presented. The results from this study validate the feasibility of a practical thermally capacitive RTR propulsion system.

  18. Design of Phoneme MIDI Codes Using the MIDI Encoding Tool “Auto-F” and Realizing Voice Synthesizing Functions Based on Musical Sounds

    NASA Astrophysics Data System (ADS)

    Modegi, Toshio

    Using our previously developed audio to MIDI code converter tool “Auto-F”, from given vocal acoustic signals we can create MIDI data, which enable to playback the voice-like signals with a standard MIDI synthesizer. Applying this tool, we are constructing a MIDI database, which consists of previously converted simple harmonic structured MIDI codes from a set of 71 Japanese male and female syllable recorded signals. And we are developing a novel voice synthesizing system based on harmonically synthesizing musical sounds, which can generate MIDI data and playback voice signals with a MIDI synthesizer by giving Japanese plain (kana) texts, referring to the syllable MIDI code database. In this paper, we propose an improved MIDI converter tool, which can produce temporally higher-resolution MIDI codes. Then we propose an algorithm separating a set of 20 consonant and vowel phoneme MIDI codes from 71 syllable MIDI converted codes in order to construct a voice synthesizing system. And, we present the evaluation results of voice synthesizing quality between these separated phoneme MIDI codes and their original syllable MIDI codes by our developed 4-syllable word listening tests.

  19. Guidelines and rules for automated assembly by robots in space

    NASA Technical Reports Server (NTRS)

    Srivastava, Sadanand

    1992-01-01

    The development of an expert system for a 'Mechanical Design System' is discussed. Two different implementation approaches are described. One is coded in C, and the other is realized by a software package - 'Exsys.' The first method has the advantage of greater flexibility and quicker responses, while the latter one is easier to develop. This report discusses the feasible ways to establish a real mechanical intelligent design system applying artificial intelligence techniques so that the products designed by this system could best meet the requirements for space assembly.

  20. Design of neurophysiologically motivated structures of time-pulse coded neurons

    NASA Astrophysics Data System (ADS)

    Krasilenko, Vladimir G.; Nikolsky, Alexander I.; Lazarev, Alexander A.; Lobodzinska, Raisa F.

    2009-04-01

    The common methodology of biologically motivated concept of building of processing sensors systems with parallel input and picture operands processing and time-pulse coding are described in paper. Advantages of such coding for creation of parallel programmed 2D-array structures for the next generation digital computers which require untraditional numerical systems for processing of analog, digital, hybrid and neuro-fuzzy operands are shown. The optoelectronic time-pulse coded intelligent neural elements (OETPCINE) simulation results and implementation results of a wide set of neuro-fuzzy logic operations are considered. The simulation results confirm engineering advantages, intellectuality, circuit flexibility of OETPCINE for creation of advanced 2D-structures. The developed equivalentor-nonequivalentor neural element has power consumption of 10mW and processing time about 10...100us.

  1. Aerodynamic simulation on massively parallel systems

    NASA Technical Reports Server (NTRS)

    Haeuser, Jochem; Simon, Horst D.

    1992-01-01

    This paper briefly addresses the computational requirements for the analysis of complete configurations of aircraft and spacecraft currently under design to be used for advanced transportation in commercial applications as well as in space flight. The discussion clearly shows that massively parallel systems are the only alternative which is both cost effective and on the other hand can provide the necessary TeraFlops, needed to satisfy the narrow design margins of modern vehicles. It is assumed that the solution of the governing physical equations, i.e., the Navier-Stokes equations which may be complemented by chemistry and turbulence models, is done on multiblock grids. This technique is situated between the fully structured approach of classical boundary fitted grids and the fully unstructured tetrahedra grids. A fully structured grid best represents the flow physics, while the unstructured grid gives best geometrical flexibility. The multiblock grid employed is structured within a block, but completely unstructured on the block level. While a completely unstructured grid is not straightforward to parallelize, the above mentioned multiblock grid is inherently parallel, in particular for multiple instruction multiple datastream (MIMD) machines. In this paper guidelines are provided for setting up or modifying an existing sequential code so that a direct parallelization on a massively parallel system is possible. Results are presented for three parallel systems, namely the Intel hypercube, the Ncube hypercube, and the FPS 500 system. Some preliminary results for an 8K CM2 machine will also be mentioned. The code run is the two dimensional grid generation module of Grid, which is a general two dimensional and three dimensional grid generation code for complex geometries. A system of nonlinear Poisson equations is solved. This code is also a good testcase for complex fluid dynamics codes, since the same datastructures are used. All systems provided good speedups, but message passing MIMD systems seem to be best suited for large miltiblock applications.

  2. Proceedings of the First NASA Formal Methods Symposium

    NASA Technical Reports Server (NTRS)

    Denney, Ewen (Editor); Giannakopoulou, Dimitra (Editor); Pasareanu, Corina S. (Editor)

    2009-01-01

    Topics covered include: Model Checking - My 27-Year Quest to Overcome the State Explosion Problem; Applying Formal Methods to NASA Projects: Transition from Research to Practice; TLA+: Whence, Wherefore, and Whither; Formal Methods Applications in Air Transportation; Theorem Proving in Intel Hardware Design; Building a Formal Model of a Human-Interactive System: Insights into the Integration of Formal Methods and Human Factors Engineering; Model Checking for Autonomic Systems Specified with ASSL; A Game-Theoretic Approach to Branching Time Abstract-Check-Refine Process; Software Model Checking Without Source Code; Generalized Abstract Symbolic Summaries; A Comparative Study of Randomized Constraint Solvers for Random-Symbolic Testing; Component-Oriented Behavior Extraction for Autonomic System Design; Automated Verification of Design Patterns with LePUS3; A Module Language for Typing by Contracts; From Goal-Oriented Requirements to Event-B Specifications; Introduction of Virtualization Technology to Multi-Process Model Checking; Comparing Techniques for Certified Static Analysis; Towards a Framework for Generating Tests to Satisfy Complex Code Coverage in Java Pathfinder; jFuzz: A Concolic Whitebox Fuzzer for Java; Machine-Checkable Timed CSP; Stochastic Formal Correctness of Numerical Algorithms; Deductive Verification of Cryptographic Software; Coloured Petri Net Refinement Specification and Correctness Proof with Coq; Modeling Guidelines for Code Generation in the Railway Signaling Context; Tactical Synthesis Of Efficient Global Search Algorithms; Towards Co-Engineering Communicating Autonomous Cyber-Physical Systems; and Formal Methods for Automated Diagnosis of Autosub 6000.

  3. Conceptual and statistical issues in couples observational research: Rationale and methods for design decisions.

    PubMed

    Baucom, Brian R W; Leo, Karena; Adamo, Colin; Georgiou, Panayiotis; Baucom, Katherine J W

    2017-12-01

    Observational behavioral coding methods are widely used for the study of relational phenomena. There are numerous guidelines for the development and implementation of these methods that include principles for creating new and adapting existing coding systems as well as principles for creating coding teams. While these principles have been successfully implemented in research on relational phenomena, the ever expanding array of phenomena being investigated with observational methods calls for a similar expansion of these principles. Specifically, guidelines are needed for decisions that arise in current areas of emphasis in couple research including observational investigation of related outcomes (e.g., relationship distress and psychological symptoms), the study of change in behavior over time, and the study of group similarities and differences in the enactment and perception of behavior. This article describes conceptual and statistical considerations involved in these 3 areas of research and presents principle- and empirically based rationale for design decisions related to these issues. A unifying principle underlying these guidelines is the need for careful consideration of fit between theory, research questions, selection of coding systems, and creation of coding teams. Implications of (mis)fit for the advancement of theory are discussed. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  4. The Modeling of Advanced BWR Fuel Designs with the NRC Fuel Depletion Codes PARCS/PATHS

    DOE PAGES

    Ward, Andrew; Downar, Thomas J.; Xu, Y.; ...

    2015-04-22

    The PATHS (PARCS Advanced Thermal Hydraulic Solver) code was developed at the University of Michigan in support of U.S. Nuclear Regulatory Commission research to solve the steady-state, two-phase, thermal-hydraulic equations for a boiling water reactor (BWR) and to provide thermal-hydraulic feedback for BWR depletion calculations with the neutronics code PARCS (Purdue Advanced Reactor Core Simulator). The simplified solution methodology, including a three-equation drift flux formulation and an optimized iteration scheme, yields very fast run times in comparison to conventional thermal-hydraulic systems codes used in the industry, while still retaining sufficient accuracy for applications such as BWR depletion calculations. Lastly, themore » capability to model advanced BWR fuel designs with part-length fuel rods and heterogeneous axial channel flow geometry has been implemented in PATHS, and the code has been validated against previously benchmarked advanced core simulators as well as BWR plant and experimental data. We describe the modifications to the codes and the results of the validation in this paper.« less

  5. Use of statecharts in the modelling of dynamic behaviour in the ATLAS DAQ prototype-1

    NASA Astrophysics Data System (ADS)

    Croll, P.; Duval, P.-Y.; Jones, R.; Kolos, S.; Sari, R. F.; Wheeler, S.

    1998-08-01

    Many applications within the ATLAS DAQ prototype-1 system have complicated dynamic behaviour which can be successfully modelled in terms of states and transitions between states. Previously, state diagrams implemented as finite-state machines have been used. Although effective, they become ungainly as system size increases. Harel statecharts address this problem by implementing additional features such as hierarchy and concurrency. The CHSM object-oriented language system is freeware which implements Harel statecharts as concurrent, hierarchical, finite-state machines (CHSMs). An evaluation of this language system by the ATLAS DAQ group has shown it to be suitable for describing the dynamic behaviour of typical DAQ applications. The language is currently being used to model the dynamic behaviour of the prototype-1 run-control system. The design is specified by means of a CHSM description file, and C++ code is obtained by running the CHSM compiler on the file. In parallel with the modelling work, a code generator has been developed which translates statecharts, drawn using the StP CASE tool, into the CHSM language. C++ code, describing the dynamic behaviour of the run-control system, has been successfully generated directly from StP statecharts using the CHSM generator and compiler. The validity of the design was tested using the simulation features of the Statemate CASE tool.

  6. A hybrid design methodology for structuring an Integrated Environmental Management System (IEMS) for shipping business.

    PubMed

    Celik, Metin

    2009-03-01

    The International Safety Management (ISM) Code defines a broad framework for the safe management and operation of merchant ships, maintaining high standards of safety and environmental protection. On the other hand, ISO 14001:2004 provides a generic, worldwide environmental management standard that has been utilized by several industries. Both the ISM Code and ISO 14001:2004 have the practical goal of establishing a sustainable Integrated Environmental Management System (IEMS) for shipping businesses. This paper presents a hybrid design methodology that shows how requirements from both standards can be combined into a single execution scheme. Specifically, the Analytic Hierarchy Process (AHP) and Fuzzy Axiomatic Design (FAD) are used to structure an IEMS for ship management companies. This research provides decision aid to maritime executives in order to enhance the environmental performance in the shipping industry.

  7. Reds, Greens, Yellows Ease the Spelling Blues.

    ERIC Educational Resources Information Center

    Irwin, Virginia

    1971-01-01

    This document reports on a color-coding innovation designed to improve the spelling ability of high school seniors. This color-coded system is based on two assumptions: that color will appeal to the students and that there are three principal reasons for misspelling. Two groups were chosen for the experiments. A basic list of spelling demons was…

  8. The Golden Rule

    ERIC Educational Resources Information Center

    Lustig, Susan

    2008-01-01

    While some Olympic results don't leave room for argument, scoring other events such as gymnastics, is subjective. So much so that in 2006, the "Code of Points" and the entire scoring system were overhauled. It is the same with school design. One might think it would be nice to have a "Code of Points," so that every education institution could…

  9. BEARCLAW: Boundary Embedded Adaptive Refinement Conservation LAW package

    NASA Astrophysics Data System (ADS)

    Mitran, Sorin

    2011-04-01

    The BEARCLAW package is a multidimensional, Eulerian AMR-capable computational code written in Fortran to solve hyperbolic systems for astrophysical applications. It is part of AstroBEAR, a hydrodynamic & magnetohydrodynamic code environment designed for a variety of astrophysical applications which allows simulations in 2, 2.5 (i.e., cylindrical), and 3 dimensions, in either cartesian or curvilinear coordinates.

  10. Automatic finite element generators

    NASA Technical Reports Server (NTRS)

    Wang, P. S.

    1984-01-01

    The design and implementation of a software system for generating finite elements and related computations are described. Exact symbolic computational techniques are employed to derive strain-displacement matrices and element stiffness matrices. Methods for dealing with the excessive growth of symbolic expressions are discussed. Automatic FORTRAN code generation is described with emphasis on improving the efficiency of the resultant code.

  11. Applying graphics user interface ot group technology classification and coding at the Boeing aerospace company

    NASA Astrophysics Data System (ADS)

    Ness, P. H.; Jacobson, H.

    1984-10-01

    The thrust of 'group technology' is toward the exploitation of similarities in component design and manufacturing process plans to achieve assembly line flow cost efficiencies for small batch production. The systematic method devised for the identification of similarities in component geometry and processing steps is a coding and classification scheme implemented by interactive CAD/CAM systems. This coding and classification scheme has led to significant increases in computer processing power, allowing rapid searches and retrievals on the basis of a 30-digit code together with user-friendly computer graphics.

  12. Interface requirements for coupling a containment code to a reactor system thermal hydraulic codes

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

    Baratta, A.J.

    1997-07-01

    To perform a complete analysis of a reactor transient, not only the primary system response but the containment response must also be accounted for. Such transients and accidents as a loss of coolant accident in both pressurized water and boiling water reactors and inadvertent operation of safety relief valves all challenge the containment and may influence flows because of containment feedback. More recently, the advanced reactor designs put forth by General Electric and Westinghouse in the US and by Framatome and Seimens in Europe rely on the containment to act as the ultimate heat sink. Techniques used by analysts andmore » engineers to analyze the interaction of the containment and the primary system were usually iterative in nature. Codes such as RELAP or RETRAN were used to analyze the primary system response and CONTAIN or CONTEMPT the containment response. The analysis was performed by first running the system code and representing the containment as a fixed pressure boundary condition. The flows were usually from the primary system to the containment initially and generally under choked conditions. Once the mass flows and timing are determined from the system codes, these conditions were input into the containment code. The resulting pressures and temperatures were then calculated and the containment performance analyzed. The disadvantage of this approach becomes evident when one performs an analysis of a rapid depressurization or a long term accident sequence in which feedback from the containment can occur. For example, in a BWR main steam line break transient, the containment heats up and becomes a source of energy for the primary system. Recent advances in programming and computer technology are available to provide an alternative approach. The author and other researchers have developed linkage codes capable of transferring data between codes at each time step allowing discrete codes to be coupled together.« less

  13. Evaluation of a bar-code system to detect unaccompanied baggage

    DOT National Transportation Integrated Search

    1988-02-01

    The objective of the Unaccompanied Baggage Detection System (UBDS) Project has : been to gain field experience with a system designed to identify passengers who : check baggage for a flight and subsequently fail to board that flight. In the first : p...

  14. NCC: A Multidisciplinary Design/Analysis Tool for Combustion Systems

    NASA Technical Reports Server (NTRS)

    Liu, Nan-Suey; Quealy, Angela

    1999-01-01

    A multi-disciplinary design/analysis tool for combustion systems is critical for optimizing the low-emission, high-performance combustor design process. Based on discussions between NASA Lewis Research Center and the jet engine companies, an industry-government team was formed in early 1995 to develop the National Combustion Code (NCC), which is an integrated system of computer codes for the design and analysis of combustion systems. NCC has advanced features that address the need to meet designer's requirements such as "assured accuracy", "fast turnaround", and "acceptable cost". The NCC development team is comprised of Allison Engine Company (Allison), CFD Research Corporation (CFDRC), GE Aircraft Engines (GEAE), NASA Lewis Research Center (LeRC), and Pratt & Whitney (P&W). This development team operates under the guidance of the NCC steering committee. The "unstructured mesh" capability and "parallel computing" are fundamental features of NCC from its inception. The NCC system is composed of a set of "elements" which includes grid generator, main flow solver, turbulence module, turbulence and chemistry interaction module, chemistry module, spray module, radiation heat transfer module, data visualization module, and a post-processor for evaluating engine performance parameters. Each element may have contributions from several team members. Such a multi-source multi-element system needs to be integrated in a way that facilitates inter-module data communication, flexibility in module selection, and ease of integration.

  15. The servicing aid tool: A teleoperated robotics system for space applications

    NASA Technical Reports Server (NTRS)

    Dorman, Keith W.; Pullen, John L.; Keksz, William O.; Eismann, Paul H.; Kowalski, Keith A.; Karlen, James P.

    1994-01-01

    The Servicing Aid Tool (SAT) is a teleoperated, force-reflecting manipulation system designed for use on the Space Shuttle. The system will assist Extravehicular Activity (EVA) servicing of spacecraft such as the Hubble Space Telescope. The SAT stands out from other robotics development programs in that special attention was given to provide a low-cost, space-qualified design which can easily and inexpensively be reconfigured and/or enhanced through the addition of existing NASA funded technology as that technology matures. SAT components are spaceflight adaptations of existing ground-based designs from Robotics Research Corporation (RRC), the leading supplier of robotics systems to the NASA and university research community in the United States. Fairchild Space is the prime contractor and provides the control electronics, safety system, system integration, and qualification testing. The manipulator consists of a 6-DOF Slave Arm mounted on a 1-DOF Positioning Link in the shuttle payload bay. The Slave Arm is controlled via a highly similar, 6-DOF, force-reflecting Master Arm from Schilling Development, Inc. This work is being performed under contract to the Goddard Space Flight Center Code, Code 442, Hubble Space Telescope Flight Systems and Servicing Project.

  16. Finite element based electric motor design optimization

    NASA Technical Reports Server (NTRS)

    Campbell, C. Warren

    1993-01-01

    The purpose of this effort was to develop a finite element code for the analysis and design of permanent magnet electric motors. These motors would drive electromechanical actuators in advanced rocket engines. The actuators would control fuel valves and thrust vector control systems. Refurbishing the hydraulic systems of the Space Shuttle after each flight is costly and time consuming. Electromechanical actuators could replace hydraulics, improve system reliability, and reduce down time.

  17. A programming environment for distributed complex computing. An overview of the Framework for Interdisciplinary Design Optimization (FIDO) project. NASA Langley TOPS exhibit H120b

    NASA Technical Reports Server (NTRS)

    Townsend, James C.; Weston, Robert P.; Eidson, Thomas M.

    1993-01-01

    The Framework for Interdisciplinary Design Optimization (FIDO) is a general programming environment for automating the distribution of complex computing tasks over a networked system of heterogeneous computers. For example, instead of manually passing a complex design problem between its diverse specialty disciplines, the FIDO system provides for automatic interactions between the discipline tasks and facilitates their communications. The FIDO system networks all the computers involved into a distributed heterogeneous computing system, so they have access to centralized data and can work on their parts of the total computation simultaneously in parallel whenever possible. Thus, each computational task can be done by the most appropriate computer. Results can be viewed as they are produced and variables changed manually for steering the process. The software is modular in order to ease migration to new problems: different codes can be substituted for each of the current code modules with little or no effect on the others. The potential for commercial use of FIDO rests in the capability it provides for automatically coordinating diverse computations on a networked system of workstations and computers. For example, FIDO could provide the coordination required for the design of vehicles or electronics or for modeling complex systems.

  18. Numerical Simulation of MIG for 42 GHz, 200 kW Gyrotron

    NASA Astrophysics Data System (ADS)

    Singh, Udaybir; Bera, Anirban; Kumar, Narendra; Purohit, L. P.; Sinha, Ashok K.

    2010-06-01

    A triode type magnetron injection gun (MIG) of a 42 GHz, 200 kW gyrotron for an Indian TOKAMAK system is designed by using the commercially available code EGUN. The operating voltages of the modulating anode and the accelerating anode are 29 kV and 65 kV respectively. The operating mode of the gyrotron is TE03 and it is operated in fundamental harmonic. The simulated results of MIG obtained with the EGUN code are validated with another trajectory code TRAK.

  19. The development of an intelligent interface to a computational fluid dynamics flow-solver code

    NASA Technical Reports Server (NTRS)

    Williams, Anthony D.

    1988-01-01

    Researchers at NASA Lewis are currently developing an 'intelligent' interface to aid in the development and use of large, computational fluid dynamics flow-solver codes for studying the internal fluid behavior of aerospace propulsion systems. This paper discusses the requirements, design, and implementation of an intelligent interface to Proteus, a general purpose, 3-D, Navier-Stokes flow solver. The interface is called PROTAIS to denote its introduction of artificial intelligence (AI) concepts to the Proteus code.

  20. The development of an intelligent interface to a computational fluid dynamics flow-solver code

    NASA Technical Reports Server (NTRS)

    Williams, Anthony D.

    1988-01-01

    Researchers at NASA Lewis are currently developing an 'intelligent' interface to aid in the development and use of large, computational fluid dynamics flow-solver codes for studying the internal fluid behavior of aerospace propulsion systems. This paper discusses the requirements, design, and implementation of an intelligent interface to Proteus, a general purpose, three-dimensional, Navier-Stokes flow solver. The interface is called PROTAIS to denote its introduction of artificial intelligence (AI) concepts to the Proteus code.

  1. Instruct coders' manual

    NASA Technical Reports Server (NTRS)

    Friend, J.

    1971-01-01

    A manual designed both as an instructional manual for beginning coders and as a reference manual for the coding language INSTRUCT, is presented. The manual includes the major programs necessary to implement the teaching system and lists the limitation of current implementation. A detailed description is given of how to code a lesson, what buttons to push, and what utility programs to use. Suggestions for debugging coded lessons and the error messages that may be received during assembly or while running the lesson are given.

  2. 13 CFR 121.1103 - What are the procedures for appealing a NAICS code designation?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... appealing a NAICS code designation? 121.1103 Section 121.1103 Business Credit and Assistance SMALL BUSINESS... Determinations and Naics Code Designations § 121.1103 What are the procedures for appealing a NAICS code... code designation and applicable size standard must be served and filed within 10 calendar days after...

  3. Design and Simulation of Material-Integrated Distributed Sensor Processing with a Code-Based Agent Platform and Mobile Multi-Agent Systems

    PubMed Central

    Bosse, Stefan

    2015-01-01

    Multi-agent systems (MAS) can be used for decentralized and self-organizing data processing in a distributed system, like a resource-constrained sensor network, enabling distributed information extraction, for example, based on pattern recognition and self-organization, by decomposing complex tasks in simpler cooperative agents. Reliable MAS-based data processing approaches can aid the material-integration of structural-monitoring applications, with agent processing platforms scaled to the microchip level. The agent behavior, based on a dynamic activity-transition graph (ATG) model, is implemented with program code storing the control and the data state of an agent, which is novel. The program code can be modified by the agent itself using code morphing techniques and is capable of migrating in the network between nodes. The program code is a self-contained unit (a container) and embeds the agent data, the initialization instructions and the ATG behavior implementation. The microchip agent processing platform used for the execution of the agent code is a standalone multi-core stack machine with a zero-operand instruction format, leading to a small-sized agent program code, low system complexity and high system performance. The agent processing is token-queue-based, similar to Petri-nets. The agent platform can be implemented in software, too, offering compatibility at the operational and code level, supporting agent processing in strong heterogeneous networks. In this work, the agent platform embedded in a large-scale distributed sensor network is simulated at the architectural level by using agent-based simulation techniques. PMID:25690550

  4. Efficient coding and detection of ultra-long IDs for visible light positioning systems.

    PubMed

    Zhang, Hualong; Yang, Chuanchuan

    2018-05-14

    Visible light positioning (VLP) is a promising technique to complement Global Navigation Satellite System (GNSS) such as Global positioning system (GPS) and BeiDou Navigation Satellite System (BDS) which features the advantage of low-cost and high accuracy. The situation becomes even more crucial for indoor environments, where satellite signals are weak or even unavailable. For large-scale application of VLP, there would be a considerable number of Light emitting diode (LED) IDs, which bring forward the demand of long LED ID detection. In particular, to provision indoor localization globally, a convenient way is to program a unique ID into each LED during manufacture. This poses a big challenge for image sensors, such as the CMOS camera in everybody's hands since the long ID covers the span of multiple frames. In this paper, we investigate the detection of ultra-long ID using rolling shutter cameras. By analyzing the pattern of data loss in each frame, we proposed a novel coding technique to improve the efficiency of LED ID detection. We studied the performance of Reed-Solomon (RS) code in this system and designed a new coding method which considered the trade-off between performance and decoding complexity. Coding technique decreases the number of frames needed in data processing, significantly reduces the detection time, and improves the accuracy of detection. Numerical and experimental results show that the detected LED ID can be much longer with the coding technique. Besides, our proposed coding method is proved to achieve a performance close to that of RS code while the decoding complexity is much lower.

  5. Design and simulation of material-integrated distributed sensor processing with a code-based agent platform and mobile multi-agent systems.

    PubMed

    Bosse, Stefan

    2015-02-16

    Multi-agent systems (MAS) can be used for decentralized and self-organizing data processing in a distributed system, like a resource-constrained sensor network, enabling distributed information extraction, for example, based on pattern recognition and self-organization, by decomposing complex tasks in simpler cooperative agents. Reliable MAS-based data processing approaches can aid the material-integration of structural-monitoring applications, with agent processing platforms scaled to the microchip level. The agent behavior, based on a dynamic activity-transition graph (ATG) model, is implemented with program code storing the control and the data state of an agent, which is novel. The program code can be modified by the agent itself using code morphing techniques and is capable of migrating in the network between nodes. The program code is a self-contained unit (a container) and embeds the agent data, the initialization instructions and the ATG behavior implementation. The microchip agent processing platform used for the execution of the agent code is a standalone multi-core stack machine with a zero-operand instruction format, leading to a small-sized agent program code, low system complexity and high system performance. The agent processing is token-queue-based, similar to Petri-nets. The agent platform can be implemented in software, too, offering compatibility at the operational and code level, supporting agent processing in strong heterogeneous networks. In this work, the agent platform embedded in a large-scale distributed sensor network is simulated at the architectural level by using agent-based simulation techniques.

  6. Study on a novel laser target detection system based on software radio technique

    NASA Astrophysics Data System (ADS)

    Song, Song; Deng, Jia-hao; Wang, Xue-tian; Gao, Zhen; Sun, Ji; Sun, Zhi-hui

    2008-12-01

    This paper presents that software radio technique is applied to laser target detection system with the pseudo-random code modulation. Based on the theory of software radio, the basic framework of the system, hardware platform, and the implementation of the software system are detailed. Also, the block diagram of the system, DSP circuit, block diagram of the pseudo-random code generator, and soft flow diagram of signal processing are designed. Experimental results have shown that the application of software radio technique provides a novel method to realize the modularization, miniaturization and intelligence of the laser target detection system, and the upgrade and improvement of the system will become simpler, more convenient, and cheaper.

  7. Multiple Ejection Effects Analysis

    DTIC Science & Technology

    1981-08-01

    in future designs . Accession For * I N’IS CRA&I PTIV TAB\\ U:,zmnounced Ja St if ic ft IonL- 1) i tributIon/ Availability Codes Avail and/or )Ibt...between aircraft separation and drogue line stretch. In the case I of the crew module, design changes were eventually adopted to provide a stable...system, and the attitude excursions are very mild. The ejection seat system underwent an important design change because of high-speed aerodynamic

  8. A tactile-output paging communication system for the deaf-blind

    NASA Technical Reports Server (NTRS)

    Baer, J. A.

    1979-01-01

    A radio frequency paging communication system that has coded vibrotactile outputs suitable for use by deaf-blind people was developed. In concept, the system consists of a base station transmitting and receiving unit and many on-body transmitting and receiving units. The completed system has seven operating modes: fire alarm; time signal; repeated single character Morse code; manual Morse code; emergency aid request; operational status test; and message acknowledge. The on-body units can be addressed in three ways: all units; a group of units; or an individual unit. All the functions developed were integrated into a single package that can be worn on the user's wrist. The control portion of the on-body unit is implemented by a microcomputer. The microcomputer is packaged in a custom-designed hybrid circuit to reduce its physical size.

  9. XSECT: A computer code for generating fuselage cross sections - user's manual

    NASA Technical Reports Server (NTRS)

    Ames, K. R.

    1982-01-01

    A computer code, XSECT, has been developed to generate fuselage cross sections from a given area distribution and wing definition. The cross sections are generated to match the wing definition while conforming to the area requirement. An iterative procedure is used to generate each cross section. Fuselage area balancing may be included in this procedure if desired. The code is intended as an aid for engineers who must first design a wing under certain aerodynamic constraints and then design a fuselage for the wing such that the contraints remain satisfied. This report contains the information necessary for accessing and executing the code, which is written in FORTRAN to execute on the Cyber 170 series computers (NOS operating system) and produces graphical output for a Tektronix 4014 CRT. The LRC graphics software is used in combination with the interface between this software and the PLOT 10 software.

  10. Faunus: An object oriented framework for molecular simulation

    PubMed Central

    Lund, Mikael; Trulsson, Martin; Persson, Björn

    2008-01-01

    Background We present a C++ class library for Monte Carlo simulation of molecular systems, including proteins in solution. The design is generic and highly modular, enabling multiple developers to easily implement additional features. The statistical mechanical methods are documented by extensive use of code comments that – subsequently – are collected to automatically build a web-based manual. Results We show how an object oriented design can be used to create an intuitively appealing coding framework for molecular simulation. This is exemplified in a minimalistic C++ program that can calculate protein protonation states. We further discuss performance issues related to high level coding abstraction. Conclusion C++ and the Standard Template Library (STL) provide a high-performance platform for generic molecular modeling. Automatic generation of code documentation from inline comments has proven particularly useful in that no separate manual needs to be maintained. PMID:18241331

  11. Design of Student Information Management Database Application System for Office and Departmental Target Responsibility System

    NASA Astrophysics Data System (ADS)

    Zhou, Hui

    It is the inevitable outcome of higher education reform to carry out office and departmental target responsibility system, in which statistical processing of student's information is an important part of student's performance review. On the basis of the analysis of the student's evaluation, the student information management database application system is designed by using relational database management system software in this paper. In order to implement the function of student information management, the functional requirement, overall structure, data sheets and fields, data sheet Association and software codes are designed in details.

  12. Optical noise-free image encryption based on quick response code and high dimension chaotic system in gyrator transform domain

    NASA Astrophysics Data System (ADS)

    Sui, Liansheng; Xu, Minjie; Tian, Ailing

    2017-04-01

    A novel optical image encryption scheme is proposed based on quick response code and high dimension chaotic system, where only the intensity distribution of encoded information is recorded as ciphertext. Initially, the quick response code is engendered from the plain image and placed in the input plane of the double random phase encoding architecture. Then, the code is encrypted to the ciphertext with noise-like distribution by using two cascaded gyrator transforms. In the process of encryption, the parameters such as rotation angles and random phase masks are generated as interim variables and functions based on Chen system. A new phase retrieval algorithm is designed to reconstruct the initial quick response code in the process of decryption, in which a priori information such as three position detection patterns is used as the support constraint. The original image can be obtained without any energy loss by scanning the decrypted code with mobile devices. The ciphertext image is the real-valued function which is more convenient for storing and transmitting. Meanwhile, the security of the proposed scheme is enhanced greatly due to high sensitivity of initial values of Chen system. Extensive cryptanalysis and simulation have performed to demonstrate the feasibility and effectiveness of the proposed scheme.

  13. A framework for development of an intelligent system for design and manufacturing of stamping dies

    NASA Astrophysics Data System (ADS)

    Hussein, H. M. A.; Kumar, S.

    2014-07-01

    An integration of computer aided design (CAD), computer aided process planning (CAPP) and computer aided manufacturing (CAM) is required for development of an intelligent system to design and manufacture stamping dies in sheet metal industries. In this paper, a framework for development of an intelligent system for design and manufacturing of stamping dies is proposed. In the proposed framework, the intelligent system is structured in form of various expert system modules for different activities of design and manufacturing of dies. All system modules are integrated with each other. The proposed system takes its input in form of a CAD file of sheet metal part, and then system modules automate all tasks related to design and manufacturing of stamping dies. Modules are coded using Visual Basic (VB) and developed on the platform of AutoCAD software.

  14. Nuclear Energy Knowledge and Validation Center (NEKVaC) Needs Workshop Summary Report

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

    Gougar, Hans

    2015-02-01

    The Department of Energy (DOE) has made significant progress developing simulation tools to predict the behavior of nuclear systems with greater accuracy and of increasing our capability to predict the behavior of these systems outside of the standard range of applications. These analytical tools require a more complex array of validation tests to accurately simulate the physics and multiple length and time scales. Results from modern simulations will allow experiment designers to narrow the range of conditions needed to bound system behavior and to optimize the deployment of instrumentation to limit the breadth and cost of the campaign. Modern validation,more » verification and uncertainty quantification (VVUQ) techniques enable analysts to extract information from experiments in a systematic manner and provide the users with a quantified uncertainty estimate. Unfortunately, the capability to perform experiments that would enable taking full advantage of the formalisms of these modern codes has progressed relatively little (with some notable exceptions in fuels and thermal-hydraulics); the majority of the experimental data available today is the "historic" data accumulated over the last decades of nuclear systems R&D. A validated code-model is a tool for users. An unvalidated code-model is useful for code developers to gain understanding, publish research results, attract funding, etc. As nuclear analysis codes have become more sophisticated, so have the measurement and validation methods and the challenges that confront them. A successful yet cost-effective validation effort requires expertise possessed only by a few, resources possessed only by the well-capitalized (or a willing collective), and a clear, well-defined objective (validating a code that is developed to satisfy the need(s) of an actual user). To that end, the Idaho National Laboratory established the Nuclear Energy Knowledge and Validation Center to address the challenges of modern code validation and to manage the knowledge from past, current, and future experimental campaigns. By pulling together the best minds involved in code development, experiment design, and validation to establish and disseminate best practices and new techniques, the Nuclear Energy Knowledge and Validation Center (NEKVaC or the ‘Center’) will be a resource for industry, DOE Programs, and academia validation efforts.« less

  15. Comparison of two- and three-dimensional flow computations with laser anemometer measurements in a transonic compressor rotor

    NASA Technical Reports Server (NTRS)

    Chima, R. V.; Strazisar, A. J.

    1982-01-01

    Two and three dimensional inviscid solutions for the flow in a transonic axial compressor rotor at design speed are compared with probe and laser anemometers measurements at near-stall and maximum-flow operating points. Experimental details of the laser anemometer system and computational details of the two dimensional axisymmetric code and three dimensional Euler code are described. Comparisons are made between relative Mach number and flow angle contours, shock location, and shock strength. A procedure for using an efficient axisymmetric code to generate downstream pressure input for computationally expensive Euler codes is discussed. A film supplement shows the calculations of the two operating points with the time-marching Euler code.

  16. Multi-Constraint Multi-Variable Optimization of Source-Driven Nuclear Systems

    NASA Astrophysics Data System (ADS)

    Watkins, Edward Francis

    1995-01-01

    A novel approach to the search for optimal designs of source-driven nuclear systems is investigated. Such systems include radiation shields, fusion reactor blankets and various neutron spectrum-shaping assemblies. The novel approach involves the replacement of the steepest-descents optimization algorithm incorporated in the code SWAN by a significantly more general and efficient sequential quadratic programming optimization algorithm provided by the code NPSOL. The resulting SWAN/NPSOL code system can be applied to more general, multi-variable, multi-constraint shield optimization problems. The constraints it accounts for may include simple bounds on variables, linear constraints, and smooth nonlinear constraints. It may also be applied to unconstrained, bound-constrained and linearly constrained optimization. The shield optimization capabilities of the SWAN/NPSOL code system is tested and verified in a variety of optimization problems: dose minimization at constant cost, cost minimization at constant dose, and multiple-nonlinear constraint optimization. The replacement of the optimization part of SWAN with NPSOL is found feasible and leads to a very substantial improvement in the complexity of optimization problems which can be efficiently handled.

  17. An Application for Normal and Critical Operations in a Tactical MLS System

    DTIC Science & Technology

    2010-12-01

    Initialization........................................................................................27 2. FatFs ...CONCLUSION ............................................................................................121 APPENDIX A. DESIGN OVERVIEW OF FATFS ...123 A. FATFS RETURN CODES ..........................................................................123

  18. 75 FR 12123 - Federal Motor Vehicle Safety Standards; Side Impact Protection; Fuel System Integrity; Electric...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-15

    ... chapter 301 of title 49, United States Code, to establish a standard designed to enhance passenger motor... criterion overemphasizes pelvic protection, which could result in designs that overload the thorax. The... the June 2008 final rule, manufacturers will have sufficient time to design the necessary...

  19. The Ninevah Mission: A design summary for an unmanned mission to Venus, volume 1

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The design summary for an unmanned mission to the planet Venus, with code name Ninevah, is presented. The design includes a Hohmann transfer trajectory analysis, propulsion trade study, an overview of the communication and instrumentation systems, power requirements, probe and lander analysis, and a weight and cost analysis.

  20. Modeling of Radiowave Propagation in a Forested Environment

    DTIC Science & Technology

    2014-09-01

    is unlimited 12b. DISTRIBUTION CODE 13. ABSTRACT (maximum 200 words) Propagation models used in wireless communication system design play an...domains. Applications in both domains require communication devices and sensors to be operated in forested environments. Various methods have been...wireless communication system design play an important role in overall link performance. Propagation models in a forested environment, in particular

  1. Integrated source and channel encoded digital communication system design study

    NASA Technical Reports Server (NTRS)

    Huth, G. K.; Trumpis, B. D.; Udalov, S.

    1975-01-01

    Various aspects of space shuttle communication systems were studied. The following major areas were investigated: burst error correction for shuttle command channels; performance optimization and design considerations for Costas receivers with and without bandpass limiting; experimental techniques for measuring low level spectral components of microwave signals; and potential modulation and coding techniques for the Ku-band return link. Results are presented.

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

    Kornfeldt, H.; Bjoerk, K.O.; Ekstroem, P.

    The protection against dynamic effects in connection with potential pipe breaks has been implemented in different ways in the development of BWR reactor designs. First-generation plant designs reflect code requirements in effect at that time which means that no piping restraint systems were designed and built into those plants. Modern designs have, in contrast, implemented full protection against damage in connection with postulated pipe breaks, as required in current codes and regulations. Moderns standards and current regulatory demands can be met for the older plants by backfitting pipe whip restraint hardware. This could lead to several practical difficulties as thesemore » installations were not anticipated in the original plant design and layout. Meeting the new demands by analysis would in this situation have great advantages. Application of leak-before-break criteria gives an alternative opportunity of meeting modem standards in reactor safety design. Analysis takes into account data specific to BWR primary system operation, actual pipe material properties, piping loads and leak detection capability. Special attention must be given to ensure that the data used reflects actual plant conditions.« less

  3. A four stage approach for ontology-based health information system design.

    PubMed

    Kuziemsky, Craig E; Lau, Francis

    2010-11-01

    To describe and illustrate a four stage methodological approach to capture user knowledge in a biomedical domain area, use that knowledge to design an ontology, and then implement and evaluate the ontology as a health information system (HIS). A hybrid participatory design-grounded theory (GT-PD) method was used to obtain data and code them for ontology development. Prototyping was used to implement the ontology as a computer-based tool. Usability testing evaluated the computer-based tool. An empirically derived domain ontology and set of three problem-solving approaches were developed as a formalized model of the concepts and categories from the GT coding. The ontology and problem-solving approaches were used to design and implement a HIS that tested favorably in usability testing. The four stage approach illustrated in this paper is useful for designing and implementing an ontology as the basis for a HIS. The approach extends existing ontology development methodologies by providing an empirical basis for theory incorporated into ontology design. Copyright © 2010 Elsevier B.V. All rights reserved.

  4. A method for the design of transonic flexible wings

    NASA Technical Reports Server (NTRS)

    Smith, Leigh Ann; Campbell, Richard L.

    1990-01-01

    Methodology was developed for designing airfoils and wings at transonic speeds which includes a technique that can account for static aeroelastic deflections. This procedure is capable of designing either supercritical or more conventional airfoil sections. Methods for including viscous effects are also illustrated and are shown to give accurate results. The methodology developed is an interactive system containing three major parts. A design module was developed which modifies airfoil sections to achieve a desired pressure distribution. This design module works in conjunction with an aerodynamic analysis module, which for this study is a small perturbation transonic flow code. Additionally, an aeroelastic module is included which determines the wing deformation due to the calculated aerodynamic loads. Because of the modular nature of the method, it can be easily coupled with any aerodynamic analysis code.

  5. Revision of seismic design codes corresponding to building damages in the ``5.12'' Wenchuan earthquake

    NASA Astrophysics Data System (ADS)

    Wang, Yayong

    2010-06-01

    A large number of buildings were seriously damaged or collapsed in the “5.12” Wenchuan earthquake. Based on field surveys and studies of damage to different types of buildings, seismic design codes have been updated. This paper briefly summarizes some of the major revisions that have been incorporated into the “Standard for classification of seismic protection of building constructions GB50223-2008” and “Code for Seismic Design of Buildings GB50011-2001.” The definition of seismic fortification class for buildings has been revisited, and as a result, the seismic classifications for schools, hospitals and other buildings that hold large populations such as evacuation shelters and information centers have been upgraded in the GB50223-2008 Code. The main aspects of the revised GB50011-2001 code include: (a) modification of the seismic intensity specified for the Provinces of Sichuan, Shanxi and Gansu; (b) basic conceptual design for retaining walls and building foundations in mountainous areas; (c) regularity of building configuration; (d) integration of masonry structures and pre-cast RC floors; (e) requirements for calculating and detailing stair shafts; and (f) limiting the use of single-bay RC frame structures. Some significant examples of damage in the epicenter areas are provided as a reference in the discussion on the consequences of collapse, the importance of duplicate structural systems, and the integration of RC and masonry structures.

  6. Tritium Mitigation/Control for Advanced Reactor System

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

    Sun, Xiaodong; Christensen, Richard; Saving, John P.

    A tritium removal facility, which is similar to the design used for tritium recovery in fusion reactors, is proposed in this study for fluoride-salt-cooled high-temperature reactors (FHRs) to result in a two-loop FHR design with the elimination of an intermediate loop. Using this approach, an economic benefit can potentially be obtained by removing the intermediate loop, while the safety concern of tritium release can be mitigated. In addition, an intermediate heat exchanger (IHX) that can yield a similar tritium permeation rate to the production rate of 1.9 Ci/day in a 1,000 MWe PWR needs to be designed to prevent themore » residual tritium that is not captured in the tritium removal system from escaping into the power cycle and ultimately the environment. The main focus of this study is to aid the mitigation of tritium permeation issue from the FHR primary side to significantly reduce the concentration of tritium in the secondary side and the process heat application side (if applicable). The goal of the research is to propose a baseline FHR system without the intermediate loop. The specific objectives to accomplish the goals are: To estimate tritium permeation behavior in FHRs; To design a tritium removal system for FHRs; To meet the same tritium permeation level in FHRs as the tritium production rate of 1.9 Ci/day in 1,000 MWe PWRs; To demonstrate economic benefits of the proposed FHR system via comparing with the three-loop FHR system. The objectives were accomplished by designing tritium removal facilities, developing a tritium analysis code, and conducting an economic analysis. In the fusion reactor community, tritium extraction has been widely investigated and researched. Borrowing the experiences from the fusion reactor community, a tritium control and mitigation system was proposed. Based on mass transport theories, a tritium analysis code was developed, and the tritium behaviors were analyzed using the developed code. Tritium removal facilities were designed and laboratory-scale experiments were proposed for the validation of the proposed tritium removal facilities.« less

  7. Program to develop a performance and heat load prediction system for multistage turbines

    NASA Technical Reports Server (NTRS)

    Sharma, OM

    1994-01-01

    Flows in low-aspect ratio turbines, such as the SSME fuel turbine, are three dimensional and highly unsteady due to the relative motion of adjacent airfoil rows and the circumferential and spanwise gradients in total pressure and temperature, The systems used to design these machines, however, are based on the assumption that the flow is steady. The codes utilized in these design systems are calibrated against turbine rig and engine data through the use of empirical correlations and experience factors. For high aspect ratio turbines, these codes yield reasonably accurate estimates of flow and temperature distributions. However, future design trends will see lower aspect ratio (reduced number of parts) and higher inlet temperature which will result in increased three dimensionality and flow unsteadiness in turbines. Analysis of recently acquired data indicate that temperature streaks and secondary flows generated in combustors and up-stream airfoils can have a large impact on the time-averaged temperature and angle distributions in downstream airfoil rows.

  8. Software design and implementation of ship heave motion monitoring system based on MBD method

    NASA Astrophysics Data System (ADS)

    Yu, Yan; Li, Yuhan; Zhang, Chunwei; Kang, Won-Hee; Ou, Jinping

    2015-03-01

    Marine transportation plays a significant role in the modern transport sector due to its advantage of low cost, large capacity. It is being attached enormous importance to all over the world. Nowadays the related areas of product development have become an existing hot spot. DSP signal processors feature micro volume, low cost, high precision, fast processing speed, which has been widely used in all kinds of monitoring systems. But traditional DSP code development process is time-consuming, inefficiency, costly and difficult. MathWorks company proposed Model-based Design (MBD) to overcome these defects. By calling the target board modules in simulink library to compile and generate the corresponding code for the target processor. And then automatically call DSP integrated development environment CCS for algorithm validation on the target processor. This paper uses the MDB to design the algorithm for the ship heave motion monitoring system. It proves the effectiveness of the MBD run successfully on the processor.

  9. The Development of a Portable Hard Disk Encryption/Decryption System with a MEMS Coded Lock

    PubMed Central

    Zhang, Weiping; Chen, Wenyuan; Tang, Jian; Xu, Peng; Li, Yibin; Li, Shengyong

    2009-01-01

    In this paper, a novel portable hard-disk encryption/decryption system with a MEMS coded lock is presented, which can authenticate the user and provide the key for the AES encryption/decryption module. The portable hard-disk encryption/decryption system is composed of the authentication module, the USB portable hard-disk interface card, the ATA protocol command decoder module, the data encryption/decryption module, the cipher key management module, the MEMS coded lock controlling circuit module, the MEMS coded lock and the hard disk. The ATA protocol circuit, the MEMS control circuit and AES encryption/decryption circuit are designed and realized by FPGA(Field Programmable Gate Array). The MEMS coded lock with two couplers and two groups of counter-meshing-gears (CMGs) are fabricated by a LIGA-like process and precision engineering method. The whole prototype was fabricated and tested. The test results show that the user's password could be correctly discriminated by the MEMS coded lock, and the AES encryption module could get the key from the MEMS coded lock. Moreover, the data in the hard-disk could be encrypted or decrypted, and the read-write speed of the dataflow could reach 17 MB/s in Ultra DMA mode. PMID:22291566

  10. Increased registration of hypertension and cancer diagnoses after the introduction of a new reimbursement system

    PubMed Central

    Hjerpe, Per; Boström, Kristina Bengtsson; Lindblad, Ulf; Merlo, Juan

    2012-01-01

    Objective To investigate the impact on ICD coding behaviour of a new case-mix reimbursement system based on coded patient diagnoses. The main hypothesis was that after the introduction of the new system the coding of chronic diseases like hypertension and cancer would increase and the variance in propensity for coding would decrease on both physician and health care centre (HCC) levels. Design Cross-sectional multilevel logistic regression analyses were performed in periods covering the time before and after the introduction of the new reimbursement system. Setting Skaraborg primary care, Sweden. Subjects All patients (n = 76 546 to 79 826) 50 years of age and older visiting 468 to 627 physicians at the 22 public HCCs in five consecutive time periods of one year each. Main outcome measures Registered codes for hypertension and cancer diseases in Skaraborg primary care database (SPCD). Results After the introduction of the new reimbursement system the adjusted prevalence of hypertension and cancer in SPCD increased from 17.4% to 32.2% and from 0.79% to 2.32%, respectively, probably partly due to an increased diagnosis coding of indirect patient contacts. The total variance in the propensity for coding declined simultaneously at the physician level for both diagnosis groups. Conclusions Changes in the healthcare reimbursement system may directly influence the contents of a research database that retrieves data from clinical practice. This should be taken into account when using such a database for research purposes, and the data should be validated for each diagnosis. PMID:23130878

  11. Concatenated Coding Using Trellis-Coded Modulation

    NASA Technical Reports Server (NTRS)

    Thompson, Michael W.

    1997-01-01

    In the late seventies and early eighties a technique known as Trellis Coded Modulation (TCM) was developed for providing spectrally efficient error correction coding. Instead of adding redundant information in the form of parity bits, redundancy is added at the modulation stage thereby increasing bandwidth efficiency. A digital communications system can be designed to use bandwidth-efficient multilevel/phase modulation such as Amplitude Shift Keying (ASK), Phase Shift Keying (PSK), Differential Phase Shift Keying (DPSK) or Quadrature Amplitude Modulation (QAM). Performance gain can be achieved by increasing the number of signals over the corresponding uncoded system to compensate for the redundancy introduced by the code. A considerable amount of research and development has been devoted toward developing good TCM codes for severely bandlimited applications. More recently, the use of TCM for satellite and deep space communications applications has received increased attention. This report describes the general approach of using a concatenated coding scheme that features TCM and RS coding. Results have indicated that substantial (6-10 dB) performance gains can be achieved with this approach with comparatively little bandwidth expansion. Since all of the bandwidth expansion is due to the RS code we see that TCM based concatenated coding results in roughly 10-50% bandwidth expansion compared to 70-150% expansion for similar concatenated scheme which use convolution code. We stress that combined coding and modulation optimization is important for achieving performance gains while maintaining spectral efficiency.

  12. HCPCS Coding: An Integral Part of Your Reimbursement Strategy.

    PubMed

    Nusgart, Marcia

    2013-12-01

    The first step to a successful reimbursement strategy is to ensure that your wound care product has the most appropriate Healthcare Common Procedure Coding System (HCPCS) code (or billing) for your product. The correct HCPCS code plays an essential role in patient access to new and existing technologies. When devising a strategy to obtain a HCPCS code for its product, companies must consider a number of factors as follows: (1) Has the product gone through the Food and Drug Administration (FDA) regulatory process or does it need to do so? Will the FDA code designation impact which HCPCS code will be assigned to your product? (2) In what "site of service" do you intend to market your product? Where will your customers use the product? Which coding system (CPT ® or HCPCS) applies to your product? (3) Does a HCPCS code for a similar product already exist? Does your product fit under the existing HCPCS code? (4) Does your product need a new HCPCS code? What is the linkage, if any, between coding, payment, and coverage for the product? Researchers and companies need to start early and place the same emphasis on a reimbursement strategy as it does on a regulatory strategy. Your reimbursement strategy staff should be involved early in the process, preferably during product research and development and clinical trial discussions.

  13. Brayton Power Conversion System Parametric Design Modelling for Nuclear Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Ashe, Thomas L.; Otting, William D.

    1993-01-01

    The parametrically based closed Brayton cycle (CBC) computer design model was developed for inclusion into the NASA LeRC overall Nuclear Electric Propulsion (NEP) end-to-end systems model. The code is intended to provide greater depth to the NEP system modeling which is required to more accurately predict the impact of specific technology on system performance. The CBC model is parametrically based to allow for conducting detailed optimization studies and to provide for easy integration into an overall optimizer driver routine. The power conversion model includes the modeling of the turbines, alternators, compressors, ducting, and heat exchangers (hot-side heat exchanger and recuperator). The code predicts performance to significant detail. The system characteristics determined include estimates of mass, efficiency, and the characteristic dimensions of the major power conversion system components. These characteristics are parametrically modeled as a function of input parameters such as the aerodynamic configuration (axial or radial), turbine inlet temperature, cycle temperature ratio, power level, lifetime, materials, and redundancy.

  14. Reengineering legacy software to object-oriented systems

    NASA Technical Reports Server (NTRS)

    Pitman, C.; Braley, D.; Fridge, E.; Plumb, A.; Izygon, M.; Mears, B.

    1994-01-01

    NASA has a legacy of complex software systems that are becoming increasingly expensive to maintain. Reengineering is one approach to modemizing these systems. Object-oriented technology, other modem software engineering principles, and automated tools can be used to reengineer the systems and will help to keep maintenance costs of the modemized systems down. The Software Technology Branch at the NASA/Johnson Space Center has been developing and testing reengineering methods and tools for several years. The Software Technology Branch is currently providing training and consulting support to several large reengineering projects at JSC, including the Reusable Objects Software Environment (ROSE) project, which is reengineering the flight analysis and design system (over 2 million lines of FORTRAN code) into object-oriented C++. Many important lessons have been learned during the past years; one of these is that the design must never be allowed to diverge from the code during maintenance and enhancement. Future work on open, integrated environments to support reengineering is being actively planned.

  15. Euler Technology Assessment for Preliminary Aircraft Design: Compressibility Predictions by Employing the Cartesian Unstructured Grid SPLITFLOW Code

    NASA Technical Reports Server (NTRS)

    Finley, Dennis B.; Karman, Steve L., Jr.

    1996-01-01

    The objective of the second phase of the Euler Technology Assessment program was to evaluate the ability of Euler computational fluid dynamics codes to predict compressible flow effects over a generic fighter wind tunnel model. This portion of the study was conducted by Lockheed Martin Tactical Aircraft Systems, using an in-house Cartesian-grid code called SPLITFLOW. The Cartesian grid technique offers several advantages, including ease of volume grid generation and reduced number of cells compared to other grid schemes. SPLITFLOW also includes grid adaption of the volume grid during the solution to resolve high-gradient regions. The SPLITFLOW code predictions of configuration forces and moments are shown to be adequate for preliminary design, including predictions of sideslip effects and the effects of geometry variations at low and high angles-of-attack. The transonic pressure prediction capabilities of SPLITFLOW are shown to be improved over subsonic comparisons. The time required to generate the results from initial surface data is on the order of several hours, including grid generation, which is compatible with the needs of the design environment.

  16. Design-Load Basis for LANL Structures, Systems, and Components

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

    I. Cuesta

    2004-09-01

    This document supports the recommendations in the Los Alamos National Laboratory (LANL) Engineering Standard Manual (ESM), Chapter 5--Structural providing the basis for the loads, analysis procedures, and codes to be used in the ESM. It also provides the justification for eliminating the loads to be considered in design, and evidence that the design basis loads are appropriate and consistent with the graded approach required by the Department of Energy (DOE) Code of Federal Regulation Nuclear Safety Management, 10, Part 830. This document focuses on (1) the primary and secondary natural phenomena hazards listed in DOE-G-420.1-2, Appendix C, (2) additional loadsmore » not related to natural phenomena hazards, and (3) the design loads on structures during construction.« less

  17. Dynamic Forms. Part 1: Functions

    NASA Technical Reports Server (NTRS)

    Meyer, George; Smith, G. Allan

    1993-01-01

    The formalism of dynamic forms is developed as a means for organizing and systematizing the design control systems. The formalism allows the designer to easily compute derivatives to various orders of large composite functions that occur in flight-control design. Such functions involve many function-of-a-function calls that may be nested to many levels. The component functions may be multiaxis, nonlinear, and they may include rotation transformations. A dynamic form is defined as a variable together with its time derivatives up to some fixed but arbitrary order. The variable may be a scalar, a vector, a matrix, a direction cosine matrix, Euler angles, or Euler parameters. Algorithms for standard elementary functions and operations of scalar dynamic forms are developed first. Then vector and matrix operations and transformations between parameterization of rotations are developed in the next level in the hierarchy. Commonly occurring algorithms in control-system design, including inversion of pure feedback systems, are developed in the third level. A large-angle, three-axis attitude servo and other examples are included to illustrate the effectiveness of the developed formalism. All algorithms were implemented in FORTRAN code. Practical experience shows that the proposed formalism may significantly improve the productivity of the design and coding process.

  18. An Infrastructure for UML-Based Code Generation Tools

    NASA Astrophysics Data System (ADS)

    Wehrmeister, Marco A.; Freitas, Edison P.; Pereira, Carlos E.

    The use of Model-Driven Engineering (MDE) techniques in the domain of distributed embedded real-time systems are gain importance in order to cope with the increasing design complexity of such systems. This paper discusses an infrastructure created to build GenERTiCA, a flexible tool that supports a MDE approach, which uses aspect-oriented concepts to handle non-functional requirements from embedded and real-time systems domain. GenERTiCA generates source code from UML models, and also performs weaving of aspects, which have been specified within the UML model. Additionally, this paper discusses the Distributed Embedded Real-Time Compact Specification (DERCS), a PIM created to support UML-based code generation tools. Some heuristics to transform UML models into DERCS, which have been implemented in GenERTiCA, are also discussed.

  19. Methodology, status and plans for development and assessment of the code ATHLET

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

    Teschendorff, V.; Austregesilo, H.; Lerchl, G.

    1997-07-01

    The thermal-hydraulic computer code ATHLET (Analysis of THermal-hydraulics of LEaks and Transients) is being developed by the Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) for the analysis of anticipated and abnormal plant transients, small and intermediate leaks as well as large breaks in light water reactors. The aim of the code development is to cover the whole spectrum of design basis and beyond design basis accidents (without core degradation) for PWRs and BWRs with only one code. The main code features are: advanced thermal-hydraulics; modular code architecture; separation between physical models and numerical methods; pre- and post-processing tools; portability. The codemore » has features that are of special interest for applications to small leaks and transients with accident management, e.g. initialization by a steady-state calculation, full-range drift-flux model, dynamic mixture level tracking. The General Control Simulation Module of ATHLET is a flexible tool for the simulation of the balance-of-plant and control systems including the various operator actions in the course of accident sequences with AM measures. The code development is accompained by a systematic and comprehensive validation program. A large number of integral experiments and separate effect tests, including the major International Standard Problems, have been calculated by GRS and by independent organizations. The ATHLET validation matrix is a well balanced set of integral and separate effects tests derived from the CSNI proposal emphasizing, however, the German combined ECC injection system which was investigated in the UPTF, PKL and LOBI test facilities.« less

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

    Rosenberg, Michael; Jonlin, Duane; Nadel, Steven

    Today’s building energy codes focus on prescriptive requirements for features of buildings that are directly controlled by the design and construction teams and verifiable by municipal inspectors. Although these code requirements have had a significant impact, they fail to influence a large slice of the building energy use pie – including not only miscellaneous plug loads, cooking equipment and commercial/industrial processes, but the maintenance and optimization of the code-mandated systems as well. Currently, code compliance is verified only through the end of construction, and there are no limits or consequences for the actual energy use in an occupied building. Inmore » the future, our suite of energy regulations will likely expand to include building efficiency, energy use or carbon emission budgets over their full life cycle. Intelligent building systems, extensive renewable energy, and a transition from fossil fuel to electric heating systems will likely be required to meet ultra-low-energy targets. This paper lays out the authors’ perspectives on how buildings may evolve over the course of the 21st century and the roles that codes and regulations will play in shaping those buildings of the future.« less

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