Science.gov

Sample records for risk-informed design methods

  1. Risk-Informed Monitoring, Verification and Accounting (RI-MVA). An NRAP White Paper Documenting Methods and a Demonstration Model for Risk-Informed MVA System Design and Operations in Geologic Carbon Sequestration

    SciTech Connect

    Unwin, Stephen D.; Sadovsky, Artyom; Sullivan, E. C.; Anderson, Richard M.

    2011-09-30

    This white paper accompanies a demonstration model that implements methods for the risk-informed design of monitoring, verification and accounting (RI-MVA) systems in geologic carbon sequestration projects. The intent is that this model will ultimately be integrated with, or interfaced with, the National Risk Assessment Partnership (NRAP) integrated assessment model (IAM). The RI-MVA methods described here apply optimization techniques in the analytical environment of NRAP risk profiles to allow systematic identification and comparison of the risk and cost attributes of MVA design options.

  2. An Example of Risk Informed Design

    NASA Technical Reports Server (NTRS)

    Banke, Rick; Grant, Warren; Wilson, Paul

    2014-01-01

    NASA Engineering requested a Probabilistic Risk Assessment (PRA) to compare the difference in the risk of Loss of Crew (LOC) and Loss of Mission (LOM) between different designs of a fluid assembly. They were concerned that the configuration favored by the design team was more susceptible to leakage than a second proposed design, but realized that a quantitative analysis to compare the risks between the two designs might strengthen their argument. The analysis showed that while the second design did help improve the probability of LOC, it did not help from a probability of LOM perspective. This drove the analysis team to propose a minor design change that would drive the probability of LOM down considerably. The analysis also demonstrated that there was another major risk driver that was not immediately obvious from a typical engineering study of the design and was therefore unexpected. None of the proposed alternatives were addressing this risk. This type of trade study demonstrates the importance of performing a PRA in order to completely understand a system's design. It allows managers to use risk as another one of the commodities (e.g., mass, cost, schedule, fault tolerance) that can be traded early in the design of a new system.

  3. Risk Informed Design as Part of the Systems Engineering Process

    NASA Technical Reports Server (NTRS)

    Deckert, George

    2010-01-01

    This slide presentation reviews the importance of Risk Informed Design (RID) as an important feature of the systems engineering process. RID is based on the principle that risk is a design commodity such as mass, volume, cost or power. It also reviews Probabilistic Risk Assessment (PRA) as it is used in the product life cycle in the development of NASA's Constellation Program.

  4. Risk Informed Assessment of Regulatory and Design Requirements for Future Nuclear Power Plants - Final Technical Report

    SciTech Connect

    Ritterbusch, Stanley; Golay, Michael; Duran, Felicia; Galyean, William; Gupta, Abhinav; Dimitrijevic, Vesna; Malsch, Marty

    2003-01-29

    OAK B188 Summary of methods proposed for risk informing the design and regulation of future nuclear power plants. All elements of the historical design and regulation process are preserved, but the methods proposed for new plants use probabilistic risk assessment methods as the primary decision making tool.

  5. Risk Informed Design and Analysis Criteria for Nuclear Structures

    SciTech Connect

    Salmon, Michael W.

    2015-06-17

    Target performance can be achieved by defining design basis ground motion from results of a probabilistic seismic hazards assessment, and introducing known levels of conservatism in the design above the DBE. ASCE 4, 43, DOE-STD-1020 defined the DBE at 4x10-4 and introduce only slight levels of conservatism in response. ASCE 4, 43, DOE-STD-1020 assume code capacities shoot for about 98% NEP. There is a need to have a uniform target (98% NEP) for code developers (ACI, AISC, etc.) to aim for. In considering strengthening options, one must also consider cost/risk reduction achieved.

  6. Risk-Informed Safety Margin Characterization Methods Development Work

    SciTech Connect

    Smith, Curtis L; Ma, Zhegang; Riley, Tom; Mandelli, Diego; Nielsen, Joseph W; Alfonsi, Andrea; Rabiti, Cristian

    2014-09-01

    This report summarizes the research activity developed during the Fiscal year 2014 within the Risk Informed Safety Margin and Characterization (RISMC) pathway within the Light Water Reactor Sustainability (LWRS) campaign. This research activity is complementary to the one presented in the INL/EXT-??? report which shows advances Probabilistic Risk Assessment Analysis using RAVEN and RELAP-7 in conjunction to novel flooding simulation tools. Here we present several analyses that prove the values of the RISMC approach in order to assess risk associated to nuclear power plants (NPPs). We focus on simulation based PRA which, in contrast to classical PRA, heavily employs system simulator codes. Firstly we compare, these two types of analyses, classical and RISMC, for a Boiling water reactor (BWR) station black out (SBO) initiating event. Secondly we present an extended BWR SBO analysis using RAVEN and RELAP-5 which address the comments and suggestions received about he original analysis presented in INL/EXT-???. This time we focus more on the stochastic analysis such probability of core damage and on the determination of the most risk-relevant factors. We also show some preliminary results regarding the comparison between RELAP5-3D and the new code RELAP-7 for a simplified Pressurized Water Reactors system. Lastly we present some conceptual ideas regarding the possibility to extended the RISMC capabilities from an off-line tool (i.e., as PRA analysis tool) to an online-tool. In this new configuration, RISMC capabilities can be used to assist and inform reactor operator during real accident scenarios.

  7. Risk-informed assessment of regulatory and design requirements for future nuclear power plants. Annual report

    SciTech Connect

    2000-08-01

    OAK B188 Risk-informed assessment of regulatory and design requirements for future nuclear power plants. Annual report. The overall goal of this research project is to support innovation in new nuclear power plant designs. This project is examining the implications, for future reactors and future safety regulation, of utilizing a new risk-informed regulatory system as a replacement for the current system. This innovation will be made possible through development of a scientific, highly risk-formed approach for the design and regulation of nuclear power plants. This approach will include the development and/or confirmation of corresponding regulatory requirements and industry standards. The major impediment to long term competitiveness of new nuclear plants in the U.S. is the capital cost component--which may need to be reduced on the order of 35% to 40% for Advanced Light Water Reactors (ALWRS) such as System 80+ and Advanced Boiling Water Reactor (ABWR). The required cost reduction for an ALWR such as AP600 or AP1000 would be expected to be less. Such reductions in capital cost will require a fundamental reevaluation of the industry standards and regulatory bases under which nuclear plants are designed and licensed. Fortunately, there is now an increasing awareness that many of the existing regulatory requirements and industry standards are not significantly contributing to safety and reliability and, therefore, are unnecessarily adding to nuclear plant costs. Not only does this degrade the economic competitiveness of nuclear energy, it results in unnecessary costs to the American electricity consumer. While addressing these concerns, this research project will be coordinated with current efforts of industry and NRC to develop risk-informed, performance-based regulations that affect the operation of the existing nuclear plants; however, this project will go further by focusing on the design of new plants.

  8. Integrating Safety Assessment Methods using the Risk Informed Safety Margins Characterization (RISMC) Approach

    SciTech Connect

    Curtis Smith; Diego Mandelli

    2013-03-01

    Safety is central to the design, licensing, operation, and economics of nuclear power plants (NPPs). As the current light water reactor (LWR) NPPs age beyond 60 years, there are possibilities for increased frequency of systems, structures, and components (SSC) degradations or failures that initiate safety significant events, reduce existing accident mitigation capabilities, or create new failure modes. Plant designers commonly “over-design” portions of NPPs and provide robustness in the form of redundant and diverse engineered safety features to ensure that, even in the case of well-beyond design basis scenarios, public health and safety will be protected with a very high degree of assurance. This form of defense-in-depth is a reasoned response to uncertainties and is often referred to generically as “safety margin.” Historically, specific safety margin provisions have been formulated primarily based on engineering judgment backed by a set of conservative engineering calculations. The ability to better characterize and quantify safety margin is important to improved decision making about LWR design, operation, and plant life extension. A systematic approach to characterization of safety margins and the subsequent margin management options represents a vital input to the licensee and regulatory analysis and decision making that will be involved. In addition, as research and development (R&D) in the LWR Sustainability (LWRS) Program and other collaborative efforts yield new data, sensors, and improved scientific understanding of physical processes that govern the aging and degradation of plant SSCs needs and opportunities to better optimize plant safety and performance will become known. To support decision making related to economics, readability, and safety, the RISMC Pathway provides methods and tools that enable mitigation options known as margins management strategies. The purpose of the RISMC Pathway R&D is to support plant decisions for risk-informed

  9. Safety margins estimation method considering uncertainties within the risk-informed decision-making framework

    SciTech Connect

    Martorell, S.; Nebot, Y.; Vilanueva, J. F.; Carlos, S.; Serradell, V.

    2006-07-01

    The adoption by regulators of the risk-informed decision-making philosophy has opened the debate on the role of the deterministic and probabilistic approaches to support regulatory matters of concern to NPP safety (e.g. safety margins, core damage frequency, etc.). However, the typical separation of the application fields does not imply that both methods cannot benefit from each other. On the contrary, there is a growing interest nowadays aimed at developing methods for using probabilistic safety analysis results into requirements and assumptions in deterministic analysis and vice versa. Thus, it appears an interesting challenge for the technical community aimed at combining best estimate thermal-hydraulic codes with probabilistic techniques to produce an effective and feasible technology, which should provide more realistic, complete and logical measure of reactor safety. This paper proposes a new unified framework to estimate safety margins using a best estimate thermal-hydraulic code with help of data and models from a level 1 LPSA (low power and shutdown probabilistic safety assessment - PSA) and considering simultaneously the uncertainty associated to both probabilistic and thermal-hydraulic codes. It is also presented an application example that demonstrates the performance and significance of the method and the relevance of the results achieved to the safety of nuclear power plants. (authors)

  10. Nuclear Energy Research Initiative. Risk Informed Assessment of Regulatory and Design Requirements for Future Nuclear Power Plants. Annual Report

    SciTech Connect

    Ritterbusch, S.E.

    2000-08-01

    The overall goal of this research project is to support innovation in new nuclear power plant designs. This project is examining the implications, for future reactors and future safety regulation, of utilizing a new risk-informed regulatory system as a replacement for the current system. This innovation will be made possible through development of a scientific, highly risk-informed approach for the design and regulation of nuclear power plants. This approach will include the development and.lor confirmation of corresponding regulatory requirements and industry standards. The major impediment to long term competitiveness of new nuclear plants in the U.S. is the capital cost component--which may need to be reduced on the order of 35% to 40% for Advanced Light Water Reactors (ALWRs) such as System 80+ and Advanced Boiling Water Reactor (ABWR). The required cost reduction for an ALWR such as AP600 or AP1000 would be expected to be less. Such reductions in capital cost will require a fundamental reevaluation of the industry standards and regulatory bases under which nuclear plants are designed and licensed. Fortunately, there is now an increasing awareness that many of the existing regulatory requirements and industry standards are not significantly contributing to safety and reliability and, therefore, are unnecessarily adding to nuclear plant costs. Not only does this degrade the economic competitiveness of nuclear energy, it results in unnecessary costs to the American electricity consumer. While addressing these concerns, this research project will be coordinated with current efforts of industry and NRC to develop risk-informed, performance-based regulations that affect the operation of the existing nuclear plants; however, this project will go farther by focusing on the design of new plants.

  11. A Design Heritage-Based Forecasting Methodology for Risk Informed Management of Advanced Systems

    NASA Technical Reports Server (NTRS)

    Maggio, Gaspare; Fragola, Joseph R.

    1999-01-01

    The development of next generation systems often carries with it the promise of improved performance, greater reliability, and reduced operational costs. These expectations arise from the use of novel designs, new materials, advanced integration and production technologies intended for functionality replacing the previous generation. However, the novelty of these nascent technologies is accompanied by lack of operational experience and, in many cases, no actual testing as well. Therefore some of the enthusiasm surrounding most new technologies may be due to inflated aspirations from lack of knowledge rather than actual future expectations. This paper proposes a design heritage approach for improved reliability forecasting of advanced system components. The basis of the design heritage approach is to relate advanced system components to similar designs currently in operation. The demonstrated performance of these components could then be used to forecast the expected performance and reliability of comparable advanced technology components. In this approach the greater the divergence of the advanced component designs from the current systems the higher the uncertainty that accompanies the associated failure estimates. Designers of advanced systems are faced with many difficult decisions. One of the most common and more difficult types of these decisions are those related to the choice between design alternatives. In the past decision-makers have found these decisions to be extremely difficult to make because they often involve the trade-off between a known performing fielded design and a promising paper design. When it comes to expected reliability performance the paper design always looks better because it is on paper and it addresses all the know failure modes of the fielded design. On the other hand there is a long, and sometimes very difficult road, between the promise of a paper design and its fulfillment; with the possibility that sometimes the reliability

  12. Cyber-Informed Engineering: The Need for a New Risk Informed and Design Methodology

    SciTech Connect

    Price, Joseph Daniel; Anderson, Robert Stephen

    2015-06-01

    Current engineering and risk management methodologies do not contain the foundational assumptions required to address the intelligent adversary’s capabilities in malevolent cyber attacks. Current methodologies focus on equipment failures or human error as initiating events for a hazard, while cyber attacks use the functionality of a trusted system to perform operations outside of the intended design and without the operator’s knowledge. These threats can by-pass or manipulate traditionally engineered safety barriers and present false information, invalidating the fundamental basis of a safety analysis. Cyber threats must be fundamentally analyzed from a completely new perspective where neither equipment nor human operation can be fully trusted. A new risk analysis and design methodology needs to be developed to address this rapidly evolving threatscape.

  13. Nine steps to risk-informed wellhead protection and management: Methods and application to the Burgberg Catchment

    NASA Astrophysics Data System (ADS)

    Nowak, W.; Enzenhoefer, R.; Bunk, T.

    2013-12-01

    Wellhead protection zones are commonly delineated via advective travel time analysis without considering any aspects of model uncertainty. In the past decade, research efforts produced quantifiable risk-based safety margins for protection zones. They are based on well vulnerability criteria (e.g., travel times, exposure times, peak concentrations) cast into a probabilistic setting, i.e., they consider model and parameter uncertainty. Practitioners still refrain from applying these new techniques for mainly three reasons. (1) They fear the possibly cost-intensive additional areal demand of probabilistic safety margins, (2) probabilistic approaches are allegedly complex, not readily available, and consume huge computing resources, and (3) uncertainty bounds are fuzzy, whereas final decisions are binary. The primary goal of this study is to show that these reservations are unjustified. We present a straightforward and computationally affordable framework based on a novel combination of well-known tools (e.g., MODFLOW, PEST, Monte Carlo). This framework provides risk-informed decision support for robust and transparent wellhead delineation under uncertainty. Thus, probabilistic risk-informed wellhead protection is possible with methods readily available for practitioners. As vivid proof of concept, we illustrate our key points on a pumped karstic well catchment, located in Germany. In the case study, we show that reliability levels can be increased by re-allocating the existing delineated area at no increase in delineated area. This is achieved by simply swapping delineated low-risk areas against previously non-delineated high-risk areas. Also, we show that further improvements may often be available at only low additional delineation area. Depending on the context, increases or reductions of delineated area directly translate to costs and benefits, if the land is priced, or if land owners need to be compensated for land use restrictions.

  14. Avoiding Cancer Risk Information

    PubMed Central

    Emanuel, Amber S.; Kiviniemi, Marc T.; Howell, Jennifer L.; Hay, Jennifer L.; Waters, Erika A.; Orom, Heather; Shepperd, James A.

    2015-01-01

    RATIONALE Perceived risk for health problems such as cancer is a central construct in many models of health decision making and a target for behavior change interventions. However, some portion of the population actively avoids cancer risk information. The prevalence of, explanations for, and consequences of such avoidance are not well understood. OBJECTIVE We examined the prevalence and demographic and psychosocial correlates of cancer risk information avoidance preference in a nationally representative sample. We also examined whether avoidance of cancer risk information corresponds with avoidance of cancer screening. RESULTS Based on our representative sample, 39% of the population indicated that they agreed or strongly agreed that they would “rather not know [their] chance of getting cancer.” This preference was stronger among older participants, female participants, and participants with lower levels of education. Preferring to avoid cancer risk information was stronger among participants who agreed with the beliefs that everything causes cancer, that there’s not much one can do to prevent cancer, and that there are too many recommendations to follow. Finally, the preference to avoid cancer risk information was associated with lower levels of screening for colon cancer. CONCLUSION These findings suggest that cancer risk information avoidance is a multi-determined phenomenon that is associated with demographic characteristics and psychosocial individual differences and also relates to engagement in cancer screening. PMID:26560410

  15. Risk Informed Margins Management as part of Risk Informed Safety Margin Characterization

    SciTech Connect

    Curtis Smith

    2014-06-01

    The ability to better characterize and quantify safety margin is important to improved decision making about Light Water Reactor (LWR) design, operation, and plant life extension. A systematic approach to characterization of safety margins and the subsequent margin management options represents a vital input to the licensee and regulatory analysis and decision making that will be involved. In addition, as research and development in the LWR Sustainability (LWRS) Program and other collaborative efforts yield new data, sensors, and improved scientific understanding of physical processes that govern the aging and degradation of plant SSCs needs and opportunities to better optimize plant safety and performance will become known. To support decision making related to economics, readability, and safety, the Risk Informed Safety Margin Characterization (RISMC) Pathway provides methods and tools that enable mitigation options known as risk informed margins management (RIMM) strategies.

  16. Considering medical risk information and communicating values: A mixed-method study of women's choice in prenatal testing.

    PubMed

    Chen, An; Tenhunen, Henni; Torkki, Paulus; Heinonen, Seppo; Lillrank, Paul; Stefanovic, Vedran

    2017-01-01

    Nowadays, an important decision for pregnant women is whether to undergo prenatal testing for aneuploidies and which tests to uptake. We investigate the factors influencing women's choices between non-invasive prenatal testing (NIPT) and invasive prenatal tests in pregnancies with elevated a priori risk of fetal aneuploidies. This is a mixed-method study. We used medical data (1st Jan 2015-31st Dec 2015) about women participating in further testing at Fetomaternal Medical Center at Helsinki University Hospital and employed Chi-square tests and ANOVA to compare the groups of women choosing different methods. Multinomial logistic regressions revealed the significant clinical factors influencing women's choice. We explored the underlying values, beliefs, attitudes and other psychosocial factors that affect women's choice by interviewing women with the Theory of Planned Behavior framework. The semi-structured interview data were processed by thematic analysis. Statistical data indicated that gestational age and counseling day were strong factors influencing women's choice. Interview data revealed that women's values and moral principles on pregnancy and childbirth chiefly determined the choices. Behavioral beliefs (e.g. safety and accuracy) and perceived choice control (e.g. easiness, rapidness and convenience) were also important and the major trade-offs happened between these constructs. Values are the determinants of women's choice. Service availability and convenience are strong factors. Medical risk status in this choice context is not highly influential. Choice aids can be developed by helping women to identify their leading values in prenatal testing and by providing lists of value-matching test options and attributes.

  17. Considering medical risk information and communicating values: A mixed-method study of women’s choice in prenatal testing

    PubMed Central

    Tenhunen, Henni; Torkki, Paulus; Heinonen, Seppo; Lillrank, Paul; Stefanovic, Vedran

    2017-01-01

    Introduction Nowadays, an important decision for pregnant women is whether to undergo prenatal testing for aneuploidies and which tests to uptake. We investigate the factors influencing women’s choices between non-invasive prenatal testing (NIPT) and invasive prenatal tests in pregnancies with elevated a priori risk of fetal aneuploidies. Methodology This is a mixed-method study. We used medical data (1st Jan 2015-31st Dec 2015) about women participating in further testing at Fetomaternal Medical Center at Helsinki University Hospital and employed Chi-square tests and ANOVA to compare the groups of women choosing different methods. Multinomial logistic regressions revealed the significant clinical factors influencing women’s choice. We explored the underlying values, beliefs, attitudes and other psychosocial factors that affect women’s choice by interviewing women with the Theory of Planned Behavior framework. The semi-structured interview data were processed by thematic analysis. Results Statistical data indicated that gestational age and counseling day were strong factors influencing women’s choice. Interview data revealed that women’s values and moral principles on pregnancy and childbirth chiefly determined the choices. Behavioral beliefs (e.g. safety and accuracy) and perceived choice control (e.g. easiness, rapidness and convenience) were also important and the major trade-offs happened between these constructs. Discussion Values are the determinants of women’s choice. Service availability and convenience are strong factors. Medical risk status in this choice context is not highly influential. Choice aids can be developed by helping women to identify their leading values in prenatal testing and by providing lists of value-matching test options and attributes. PMID:28355226

  18. Risk Informed Assessment of Regulatory and Design Requirements for Future Nuclear Power Plants (Cooperative Agreement DE-FC03-99SF21902, Am. M004) Final Technical Report

    SciTech Connect

    Stanley E. Ritterbusch, et. al.

    2003-01-29

    OAK-B135 Research under this project addresses the barriers to long term use of nuclear-generated electricity in the United States. It was agreed that a very basic and significant change to the current method of design and regulation was needed. That is, it was believed that the cost reduction goal could not be met by fixing the current system (i.e., an evolutionary approach) and a new, more advanced approach for this project would be needed. It is believed that a completely new design and regulatory process would have to be developed--a ''clean sheet of paper'' approach. This new approach would start with risk-based methods, would establish probabilistic design criteria, and would implement defense-in-depth only when necessary (1) to meet public policy issues (e.g., use of a containment building no matter how low the probability of a large release is) and (2) to address uncertainties in probabilistic methods and equipment performance. This new approach is significantly different from the Nuclear Regulatory Commission's (NRC) current risk-informed program for operating plants. For our new approach, risk-based methods are the primary means for assuring plant safety, whereas in the NRC's current approach, defense-in-depth remains the primary means of assuring safety. The primary accomplishments in the first year--Phase 1 were (1) the establishment of a new, highly risk-informed design and regulatory framework, (2) the establishment of the preliminary version of the new, highly risk-informed design process, (3) core damage frequency predictions showing that, based on new, lower pipe rupture probabilities, the design of the emergency core cooling system equipment can be simplified without reducing plant safety, and (4) the initial development of methods for including uncertainties in a new integrated structures-systems design model. Under the new regulatory framework, options for the use of ''design basis accidents'' were evaluated. It is expected that design basis

  19. Designing ROW Methods

    NASA Technical Reports Server (NTRS)

    Freed, Alan D.

    1996-01-01

    There are many aspects to consider when designing a Rosenbrock-Wanner-Wolfbrandt (ROW) method for the numerical integration of ordinary differential equations (ODE's) solving initial value problems (IVP's). The process can be simplified by constructing ROW methods around good Runge-Kutta (RK) methods. The formulation of a new, simple, embedded, third-order, ROW method demonstrates this design approach.

  20. Progress toward risk informed regulation

    SciTech Connect

    Rogers, K.C.

    1997-01-01

    For the last several years, the NRC, with encouragement from the industry, has been moving in the direction of risk informed regulation. This is consistent with the regulatory principle of efficiency, formally adopted by the Nuclear Regulatory Commission in 1991, which requires that regulatory activities be consistent with the degree of risk reduction they achieve. Probabilistic risk analysis has become the tool of choice for selecting the best of several alternatives. Closely related to risk informed regulation is the development of performance based rules. Such rules focus on the end result to be achieved. They do not specify the process, but instead establish the goals to be reached and how the achievement of those goals is to be judged. The inspection and enforcement activity is based on whether or not the goals have been met. The author goes on to offer comments on the history of the development of this process and its probable development in the future. He also addresses some issues which must be resolved or at least acknowledged. The success of risk informed regulation ultimately depends on having sufficiently reliable data to allow quantification of regulatory alternatives in terms of relative risk. Perhaps the area of human reliability and organizational performance has the greatest potential for improvement in reactor safety. The ability to model human performance is significantly less developed that the ability to model mechanical or electrical systems. The move toward risk informed, performance based regulation provides an unusual, perhaps unique, opportunity to establish a more rational, more effective basis for regulation.

  1. Air Risk Information Support Center

    SciTech Connect

    Shoaf, C.R.; Guth, D.J.

    1990-12-31

    The Air Risk Information Support Center (Air RISC) was initiated in early 1988 by the US Environmental Protection Agency`s (EPA) Office of Health and Environmental Assessment (OHEA) and the Office of Air Quality Planning and Standards (OAQPS) as a technology transfer effort that would focus on providing information to state and local environmental agencies and to EPA Regional Offices in the areas of health, risk, and exposure assessment for toxic air pollutants. Technical information is fostered and disseminated by Air RISCs three primary activities: (1) a {open_quotes}hotline{close_quotes}, (2) quick turn-around technical assistance projects, and (3) general technical guidance projects. 1 ref., 2 figs.

  2. Communicating risk information and warnings

    USGS Publications Warehouse

    Mileti, D. S.

    1990-01-01

    Major advances have occurred over the last 20 years about how to effectively communicate risk information and warnings to the public. These lessons have been hard won. Knowledge has mounted on the finding from social scientific studies of risk communication failures, successes and those which fell somewhere in between. Moreover, the last 2 decades have borne witness to the brith, cultivation, and blossoming of information sharing between those physical scientists who discover new information about risk and those communcation scientists who trace its diffusion and then measure pbulic reaction. 

  3. Parameter Plane Design Method

    DTIC Science & Technology

    1989-03-01

    Th usr a toente aninteer a thca sms b esta 1 Fp-ocsing 2. Enter P1 values, lwgt, ldig - > 9 Table I give us proper values. Table 1. PARAMETER TABLE...necessary and identify by block number) In this thesis a control systems analysis package is developed using parameter plane methods. It is an interactive...designer is able to choose values of the parameters which provide a good compromise between cost and dynamic behavior. 20 Distribution Availability of

  4. Integrated risk information system (IRIS)

    SciTech Connect

    Tuxen, L.

    1990-12-31

    The Integrated Risk Information System (IRIS) is an electronic information system developed by the US Environmental Protection Agency (EPA) containing information related to health risk assessment. IRIS is the Agency`s primary vehicle for communication of chronic health hazard information that represents Agency consensus following comprehensive review by intra-Agency work groups. The original purpose for developing IRIS was to provide guidance to EPA personnel in making risk management decisions. This original purpose for developing IRIS was to guidance to EPA personnel in making risk management decisions. This role has expanded and evolved with wider access and use of the system. IRIS contains chemical-specific information in summary format for approximately 500 chemicals. IRIS is available to the general public on the National Library of Medicine`s Toxicology Data Network (TOXNET) and on diskettes through the National Technical Information Service (NTIS).

  5. Control system design method

    DOEpatents

    Wilson, David G [Tijeras, NM; Robinett, III, Rush D.

    2012-02-21

    A control system design method and concomitant control system comprising representing a physical apparatus to be controlled as a Hamiltonian system, determining elements of the Hamiltonian system representation which are power generators, power dissipators, and power storage devices, analyzing stability and performance of the Hamiltonian system based on the results of the determining step and determining necessary and sufficient conditions for stability of the Hamiltonian system, creating a stable control system based on the results of the analyzing step, and employing the resulting control system to control the physical apparatus.

  6. TU-EF-204-09: A Preliminary Method of Risk-Informed Optimization of Tube Current Modulation for Dose Reduction in CT

    SciTech Connect

    Gao, Y; Liu, B; Kalra, M; Caracappa, P; Liu, T; Li, X; Xu, X

    2015-06-15

    Purpose: X-rays from CT scans can increase cancer risk to patients. Lifetime Attributable Risk of Cancer Incidence for adult patients has been investigated and shown to decrease as patient age. However, a new risk model shows an increasing risk trend for several radiosensitive organs for middle age patients. This study investigates the feasibility of a general method for optimizing tube current modulation (TCM) functions to minimize risk by reducing radiation dose to radiosensitive organs of patients. Methods: Organ-based TCM has been investigated in literature for eye lens dose and breast dose. Adopting the concept in organ-based TCM, this study seeks to find an optimized tube current for minimal total risk to breasts and lungs by reducing dose to these organs. The contributions of each CT view to organ dose are determined through simulations of CT scan view-by-view using a GPU-based fast Monte Carlo code, ARCHER. A Linear Programming problem is established for tube current optimization, with Monte Carlo results as weighting factors at each view. A pre-determined dose is used as upper dose boundary, and tube current of each view is optimized to minimize the total risk. Results: An optimized tube current is found to minimize the total risk of lungs and breasts: compared to fixed current, the risk is reduced by 13%, with breast dose reduced by 38% and lung dose reduced by 7%. The average tube current is maintained during optimization to maintain image quality. In addition, dose to other organs in chest region is slightly affected, with relative change in dose smaller than 10%. Conclusion: Optimized tube current plans can be generated to minimize cancer risk to lungs and breasts while maintaining image quality. In the future, various risk models and greater number of projections per rotation will be simulated on phantoms of different gender and age. National Institutes of Health R01EB015478.

  7. Method for Design Rotation

    DTIC Science & Technology

    1993-08-01

    desirability of a rotation as a function of the set of planar angles. Criteria for the symmetry of the design (such as the same set of factor levels for...P is -1. Hence there is no theoretical problem in obtaining rotations of a design; there are only the practical questions Why rotate a design? And...star points, which can be represented in a shorthand notation by the permutations of (±1,0, "’" , 0), and (c) factorial points, which are a two- level

  8. NASA Risk-Informed Decision Making Handbook

    NASA Technical Reports Server (NTRS)

    Dezfuli, Homayoon; Stamatelatos, Michael; Maggio, Gaspare; Everett, Christopher; Youngblood, Robert; Rutledge, Peter; Benjamin, Allan; Williams, Rodney; Smith, Curtis; Guarro, Sergio

    2010-01-01

    This handbook provides guidance for conducting risk-informed decision making in the context of NASA risk management (RM), with a focus on the types of direction-setting key decisions that are characteristic of the NASA program and project life cycles, and which produce derived requirements in accordance with existing systems engineering practices that flow down through the NASA organizational hierarchy. The guidance in this handbook is not meant to be prescriptive. Instead, it is meant to be general enough, and contain a sufficient diversity of examples, to enable the reader to adapt the methods as needed to the particular decision problems that he or she faces. The handbook highlights major issues to consider when making decisions in the presence of potentially significant uncertainty, so that the user is better able to recognize and avoid pitfalls that might otherwise be experienced.

  9. Aircraft digital control design methods

    NASA Technical Reports Server (NTRS)

    Powell, J. D.; Parsons, E.; Tashker, M. G.

    1976-01-01

    Variations in design methods for aircraft digital flight control are evaluated and compared. The methods fall into two categories; those where the design is done in the continuous domain (or s plane) and those where the design is done in the discrete domain (or z plane). Design method fidelity is evaluated by examining closed loop root movement and the frequency response of the discretely controlled continuous aircraft. It was found that all methods provided acceptable performance for sample rates greater than 10 cps except the uncompensated s plane design method which was acceptable above 20 cps. A design procedure based on optimal control methods was proposed that provided the best fidelity at very slow sample rates and required no design iterations for changing sample rates.

  10. RISK-INFORMED SAFETY MARGIN CHARACTERIZATION

    SciTech Connect

    Nam Dinh; Ronaldo Szilard

    2009-07-01

    The concept of safety margins has served as a fundamental principle in the design and operation of commercial nuclear power plants (NPPs). Defined as the minimum distance between a system’s “loading” and its “capacity”, plant design and operation is predicated on ensuring an adequate safety margin for safety-significant parameters (e.g., fuel cladding temperature, containment pressure, etc.) is provided over the spectrum of anticipated plant operating, transient and accident conditions. To meet the anticipated challenges associated with extending the operational lifetimes of the current fleet of operating NPPs, the United States Department of Energy (USDOE), the Idaho National Laboratory (INL) and the Electric Power Research Institute (EPRI) have developed a collaboration to conduct coordinated research to identify and address the technological challenges and opportunities that likely would affect the safe and economic operation of the existing NPP fleet over the postulated long-term time horizons. In this paper we describe a framework for developing and implementing a Risk-Informed Safety Margin Characterization (RISMC) approach to evaluate and manage changes in plant safety margins over long time horizons.

  11. Risk-Informed Assessment Methodology Development and Application

    SciTech Connect

    Sung Goo Chi; Seok Jeong Park; Chul Jin Choi; Ritterbusch, S.E.; Jacob, M.C.

    2002-07-01

    Westinghouse Electric Company (WEC) has been working with Korea Power Engineering Company (KOPEC) on a US Department of Energy (DOE) sponsored Nuclear Energy Research Initiative (NERI) project through a collaborative agreement established for the domestic NERI program. The project deals with Risk-Informed Assessment (RIA) of regulatory and design requirements of future nuclear power plants. An objective of the RIA project is to develop a risk-informed design process, which focuses on identifying and incorporating advanced features into future nuclear power plants (NPPs) that would meet risk goals in a cost-effective manner. The RIA design methodology is proposed to accomplish this objective. This paper discusses the development of this methodology and demonstrates its application in the design of plant systems for future NPPs. Advanced conceptual plant systems consisting of an advanced Emergency Core Cooling System (ECCS) and Emergency Feedwater System (EFWS) for a NPP were developed and the risk-informed design process was exercised to demonstrate the viability and feasibility of the RIA design methodology. Best estimate Loss-of-Coolant Accident (LOCA) analyses were performed to validate the PSA success criteria for the NPP. The results of the analyses show that the PSA success criteria can be met using the advanced conceptual systems and that the RIA design methodology is a viable and appropriate means of designing key features of risk-significant NPP systems. (authors)

  12. PRISM: a planned risk information seeking model.

    PubMed

    Kahlor, LeeAnn

    2010-06-01

    Recent attention on health-related information seeking has focused primarily on information seeking within specific health and health risk contexts. This study attempts to shift some of that focus to individual-level variables that may impact health risk information seeking across contexts. To locate these variables, the researcher posits an integrated model, the Planned Risk Information Seeking Model (PRISM). The model, which treats risk information seeking as a deliberate (planned) behavior, maps variables found in the Theory of Planned Behavior (TPB; Ajzen, 1991) and the Risk Information Seeking and Processing Model (RISP; Griffin, Dunwoody, & Neuwirth, 1999), and posits linkages among those variables. This effort is further informed by Kahlor's (2007) Augmented RISP, the Theory of Motivated Information Management (Afifi & Weiner, 2004), the Comprehensive Model of Information Seeking (Johnson & Meischke, 1993), the Health Information Acquisition Model (Freimuth, Stein, & Kean, 1989), and the Extended Parallel Processing Model (Witte, 1998). The resulting integrated model accounted for 59% of the variance in health risk information-seeking intent and performed better than the TPB or the RISP alone.

  13. Communicating genetic risk information within families: a review.

    PubMed

    Wiseman, Mel; Dancyger, Caroline; Michie, Susan

    2010-12-01

    This review of family communication of genetic risk information addresses questions of what the functions and influences on communication are; what, who and how family members are told about genetic risk information; what the impact for counsellee, relative and relationships are; whether there are differences by gender and condition; and what theories and methodologies are used. A systematic search strategy identified peer-reviewed journal articles published 1985-2009 using a mixture of methodologies. A Narrative Synthesis was used to extract and summarise data relevant to the research questions. This review identified 33 articles which found a consistent pattern of findings that communication about genetic risk within families is influenced by individual beliefs about the desirability of communicating genetic risk and by closeness of relationships within the family. None of the studies directly investigated the impact of communication on counsellees or their families, differences according to gender of counsellee or by condition nor alternative methods of communication with relatives. The findings mainly apply to late onset conditions such as Hereditary Breast and Ovarian Cancer. The most frequently used theory was Family Systems Theory and methods were generally qualitative. This review points to multifactorial influences on who is communicated with in families and what they are told about genetic risk information. Further research is required to investigate the impact of genetic risk information on family systems and differences between genders and conditions.

  14. Developing a Methodology for Risk-Informed Trade-Space Analysis in Acquisition

    DTIC Science & Technology

    2015-01-01

    Craig A. Bond, Lauren A. Mayer, Michael E. McMahon, James G. Kallimani, Ricardo Sanchez Developing a Methodology for Risk- Informed Trade -Space...Methodology for Risk-Informed Trade -Space Analysis in Acquisition 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d...project “Developing a Method- ology Framework for Conducting Risk-Informed Trade Space Analy- ses.” The primary objective of this study was to

  15. Stochastic Methods for Aircraft Design

    NASA Technical Reports Server (NTRS)

    Pelz, Richard B.; Ogot, Madara

    1998-01-01

    The global stochastic optimization method, simulated annealing (SA), was adapted and applied to various problems in aircraft design. The research was aimed at overcoming the problem of finding an optimal design in a space with multiple minima and roughness ubiquitous to numerically generated nonlinear objective functions. SA was modified to reduce the number of objective function evaluations for an optimal design, historically the main criticism of stochastic methods. SA was applied to many CFD/MDO problems including: low sonic-boom bodies, minimum drag on supersonic fore-bodies, minimum drag on supersonic aeroelastic fore-bodies, minimum drag on HSCT aeroelastic wings, FLOPS preliminary design code, another preliminary aircraft design study with vortex lattice aerodynamics, HSR complete aircraft aerodynamics. In every case, SA provided a simple, robust and reliable optimization method which found optimal designs in order 100 objective function evaluations. Perhaps most importantly, from this academic/industrial project, technology has been successfully transferred; this method is the method of choice for optimization problems at Northrop Grumman.

  16. Design method of supercavitating pumps

    NASA Astrophysics Data System (ADS)

    Kulagin, V.; Likhachev, D.; Li, F. C.

    2016-05-01

    The problem of effective supercavitating (SC) pump is solved, and optimum load distribution along the radius of the blade is found taking into account clearance, degree of cavitation development, influence of finite number of blades, and centrifugal forces. Sufficient accuracy can be obtained using the equivalent flat SC-grid for design of any SC-mechanisms, applying the “grid effect” coefficient and substituting the skewed flow calculated for grids of flat plates with the infinite attached cavitation caverns. This article gives the universal design method and provides an example of SC-pump design.

  17. Risk-Informed Safety Assurance and Probabilistic Assessment of Mission-Critical Software-Intensive Systems

    NASA Technical Reports Server (NTRS)

    Guarro, Sergio B.

    2010-01-01

    This report validates and documents the detailed features and practical application of the framework for software intensive digital systems risk assessment and risk-informed safety assurance presented in the NASA PRA Procedures Guide for Managers and Practitioner. This framework, called herein the "Context-based Software Risk Model" (CSRM), enables the assessment of the contribution of software and software-intensive digital systems to overall system risk, in a manner which is entirely compatible and integrated with the format of a "standard" Probabilistic Risk Assessment (PRA), as currently documented and applied for NASA missions and applications. The CSRM also provides a risk-informed path and criteria for conducting organized and systematic digital system and software testing so that, within this risk-informed paradigm, the achievement of a quantitatively defined level of safety and mission success assurance may be targeted and demonstrated. The framework is based on the concept of context-dependent software risk scenarios and on the modeling of such scenarios via the use of traditional PRA techniques - i.e., event trees and fault trees - in combination with more advanced modeling devices such as the Dynamic Flowgraph Methodology (DFM) or other dynamic logic-modeling representations. The scenarios can be synthesized and quantified in a conditional logic and probabilistic formulation. The application of the CSRM method documented in this report refers to the MiniAERCam system designed and developed by the NASA Johnson Space Center.

  18. Risk-informed Maintenance for Non-coherent Systems

    NASA Astrophysics Data System (ADS)

    Tao, Ye

    Probabilistic Safety Assessment (PSA) is a systematic and comprehensive methodology to evaluate risks associated with a complex engineered technological entity. The information provided by PSA has been increasingly implemented for regulatory purposes but rarely used in providing information for operation and maintenance activities. As one of the key parts in PSA, Fault Tree Analysis (FTA) attempts to model and analyze failure processes of engineering and biological systems. The fault trees are composed of logic diagrams that display the state of the system and are constructed using graphical design techniques. Risk Importance Measures (RIMs) are information that can be obtained from both qualitative and quantitative aspects of FTA. Components within a system can be ranked with respect to each specific criterion defined by each RIM. Through a RIM, a ranking of the components or basic events can be obtained and provide valuable information for risk-informed decision making. Various RIMs have been applied in various applications. In order to provide a thorough understanding of RIMs and interpret the results, they are categorized with respect to risk significance (RS) and safety significance (SS) in this thesis. This has also tied them into different maintenance activities. When RIMs are used for maintenance purposes, it is called risk-informed maintenance. On the other hand, the majority of work produced on the FTA method has been concentrated on failure logic diagrams restricted to the direct or implied use of AND and OR operators. Such systems are considered as coherent systems. However, the NOT logic can also contribute to the information produced by PSA. The importance analysis of non-coherent systems is rather limited, even though the field has received more and more attention over the years. The non-coherent systems introduce difficulties in both qualitative and quantitative assessment of the fault tree compared with the coherent systems. In this thesis, a set

  19. DSSTox EPA Integrated Risk Information System Structure ...

    EPA Pesticide Factsheets

    EPA's Integrated Risk Information System (IRIS) database was developed and is maintained by EPA's Office of Research and Developement, National Center for Environmental Assessment. IRIS is a database of human health effects that may result from exposure to various substances found in the environment. The information in IRIS is intended for those without extensive training in toxicology, but with some knowledge of sciences. IRIS chemical files contain descriptive and quantitative information in oral reference doses and inhalation reference concentrations and hazard identification, oral slope factors, and oral and inhalation unit risks for carcinogenic effects.

  20. Loss of Coolant Accident (LOCA) / Emergency Core Coolant System (ECCS Evaluation of Risk-Informed Margins Management Strategies for a Representative Pressurized Water Reactor (PWR)

    SciTech Connect

    Szilard, Ronaldo Henriques

    2016-09-01

    A Risk Informed Safety Margin Characterization (RISMC) toolkit and methodology are proposed for investigating nuclear power plant core, fuels design and safety analysis, including postulated Loss-of-Coolant Accident (LOCA) analysis. This toolkit, under an integrated evaluation model framework, is name LOCA toolkit for the US (LOTUS). This demonstration includes coupled analysis of core design, fuel design, thermal hydraulics and systems analysis, using advanced risk analysis tools and methods to investigate a wide range of results.

  1. A historical perspective of risk-informed regulation

    SciTech Connect

    Campbell, P.L.

    1996-12-01

    In Federal studies, the process of using risk information is described as having two general components: (1) risk assessment - the application of credible scientific principles and statistical methods to develop estimates of the likely effects of natural phenomena and human factors and the characterization of these estimates in a form appropriate for the intended audience (e.g., agency decisionmakers, public); and (2) risk management - the process of weighing policy alternatives and selecting the most appropriate regulatory action, integrating the results of risk assessment with engineering data with social, economic, and political concerns to reach a decision. This paper discusses largely the second component.

  2. Incorporating cancer risk information into general practice: a qualitative study using focus groups with health professionals

    PubMed Central

    Usher-Smith, Juliet A; Silarova, Barbora; Ward, Alison; Youell, Jane; Muir, Kenneth R; Campbell, Jackie; Warcaba, Joanne

    2017-01-01

    Background It is estimated that approximately 40% of all cases of cancer are attributable to lifestyle factors. Providing people with personalised information about their future risk of cancer may help promote behaviour change. Aim To explore the views of health professionals on incorporating personalised cancer risk information, based on lifestyle factors, into general practice. Design and setting Qualitative study using data from six focus groups with a total of 24 general practice health professionals from the NHS Nene Clinical Commissioning Group in England. Method The focus groups were guided by a schedule covering current provision of lifestyle advice relating to cancer and views on incorporating personalised cancer risk information. Data were audiotaped, transcribed verbatim, and then analysed using thematic analysis. Results Providing lifestyle advice was viewed as a core activity within general practice but the influence of lifestyle on cancer risk was rarely discussed. The word ‘cancer’ was seen as a potentially powerful motivator for lifestyle change but the fact that it could generate health anxiety was also recognised. Most focus group participants felt that a numerical risk estimate was more likely to influence behaviour than generic advice. All felt that general practice should provide this information, but there was a clear need for additional resources for it to be offered widely. Conclusion Study participants were in support of providing personalised cancer risk information in general practice. The findings highlight a number of potential benefits and challenges that will inform the future development of interventions in general practice to promote behaviour change for cancer prevention. PMID:28193618

  3. Experimental design methods for bioengineering applications.

    PubMed

    Keskin Gündoğdu, Tuğba; Deniz, İrem; Çalışkan, Gülizar; Şahin, Erdem Sefa; Azbar, Nuri

    2016-01-01

    Experimental design is a form of process analysis in which certain factors are selected to obtain the desired responses of interest. It may also be used for the determination of the effects of various independent factors on a dependent factor. The bioengineering discipline includes many different areas of scientific interest, and each study area is affected and governed by many different factors. Briefly analyzing the important factors and selecting an experimental design for optimization are very effective tools for the design of any bioprocess under question. This review summarizes experimental design methods that can be used to investigate various factors relating to bioengineering processes. The experimental methods generally used in bioengineering are as follows: full factorial design, fractional factorial design, Plackett-Burman design, Taguchi design, Box-Behnken design and central composite design. These design methods are briefly introduced, and then the application of these design methods to study different bioengineering processes is analyzed.

  4. Review of freeform TIR collimator design methods

    NASA Astrophysics Data System (ADS)

    Talpur, Taimoor; Herkommer, Alois

    2016-04-01

    Total internal reflection (TIR) collimators are essential illumination components providing high efficiency and uniformity in a compact geometry. Various illumination design methods have been developed for designing such collimators, including tailoring methods, design via optimization, the mapping and feedback method, and the simultaneous multiple surface (SMS) method. This paper provides an overview of the different methods and compares the performance of the methods along with their advantages and their limitations.

  5. RISK-INFORMED BALANCING OF SAFETY, NONPROLIFERATION, AND ECONOMICS FOR THE SFR

    SciTech Connect

    Apostolakis, George; Driscoll, Michael; Golay, Michael; Kadak, Andrew; Todreas, Neil; Aldmir, Tunc; Denning, Richard; Lineberry, Michael

    2011-10-20

    A substantial barrier to the implementation of Sodium-cooled Fast Reactor (SFR) technology in the short term is the perception that they would not be economically competitive with advanced light water reactors. With increased acceptance of risk-informed regulation, the opportunity exists to reduce the costs of a nuclear power plant at the design stage without applying excessive conservatism that is not needed in treating low risk events. In the report, NUREG-1860, the U.S. Nuclear Regulatory Commission describes developmental activities associated with a risk-informed, scenario-based technology neutral framework (TNF) for regulation. It provides quantitative yardsticks against which the adequacy of safety risks can be judged. We extend these concepts to treatment of proliferation risks. The objective of our project is to develop a risk-informed design process for minimizing the cost of electricity generation within constraints of adequate safety and proliferation risks. This report describes the design and use of this design optimization process within the context of reducing the capital cost and levelized cost of electricity production for a small (possibly modular) SFR. Our project provides not only an evaluation of the feasibility of a risk-informed design process but also a practical test of the applicability of the TNF to an actual advanced, non-LWR design. The report provides results of five safety related and one proliferation related case studies of innovative design alternatives. Applied to previously proposed SFR nuclear energy system concepts We find that the TNF provides a feasible initial basis for licensing new reactors. However, it is incomplete. We recommend improvements in terms of requiring acceptance standards for total safety risks, and we propose a framework for regulation of proliferation risks. We also demonstrate methods for evaluation of proliferation risks. We also suggest revisions to scenario-specific safety risk acceptance standards

  6. Spacesuit Radiation Shield Design Methods

    NASA Technical Reports Server (NTRS)

    Wilson, John W.; Anderson, Brooke M.; Cucinotta, Francis A.; Ware, J.; Zeitlin, Cary J.

    2006-01-01

    Meeting radiation protection requirements during EVA is predominantly an operational issue with some potential considerations for temporary shelter. The issue of spacesuit shielding is mainly guided by the potential of accidental exposure when operational and temporary shelter considerations fail to maintain exposures within operational limits. In this case, very high exposure levels are possible which could result in observable health effects and even be life threatening. Under these assumptions, potential spacesuit radiation exposures have been studied using known historical solar particle events to gain insight on the usefulness of modification of spacesuit design in which the control of skin exposure is a critical design issue and reduction of blood forming organ exposure is desirable. Transition to a new spacesuit design including soft upper-torso and reconfigured life support hardware gives an opportunity to optimize the next generation spacesuit for reduced potential health effects during an accidental exposure.

  7. Directory of Design Support Methods

    DTIC Science & Technology

    2005-08-01

    design’s resulting unique risk character in comparison with either another competing system and/or the new 100-point worst-case model (above). 5. It...programs, acquire required skills / competencies , find out where the money is being spent and where to allocate resources for greatest impact. ADVISOR Key...required to run one or multiple training programs, gain required skills and competencies as well as find out where the money is being spent - i.e

  8. FEEDBACK DESIGN METHOD REVIEW AND COMPARISON.

    SciTech Connect

    ONILLON,E.

    1999-03-29

    Different methods for feedback designs are compared. These includes classical Proportional Integral Derivative (P. I. D.), state variable based methods like pole placement, Linear Quadratic Regulator (L. Q. R.), H-infinity and p-analysis. These methods are then applied for the design and analysis of the RHIC phase and radial loop, yielding a performance, stability and robustness comparison.

  9. Design for validation, based on formal methods

    NASA Technical Reports Server (NTRS)

    Butler, Ricky W.

    1990-01-01

    Validation of ultra-reliable systems decomposes into two subproblems: (1) quantification of probability of system failure due to physical failure; (2) establishing that Design Errors are not present. Methods of design, testing, and analysis of ultra-reliable software are discussed. It is concluded that a design-for-validation based on formal methods is needed for the digital flight control systems problem, and also that formal methods will play a major role in the development of future high reliability digital systems.

  10. Design Methods for Clinical Systems

    PubMed Central

    Blum, B.I.

    1986-01-01

    This paper presents a brief introduction to the techniques, methods and tools used to implement clinical systems. It begins with a taxonomy of software systems, describes the classic approach to development, provides some guidelines for the planning and management of software projects, and finishes with a guide to further reading. The conclusions are that there is no single right way to develop software, that most decisions are based upon judgment built from experience, and that there are tools that can automate some of the better understood tasks.

  11. Guided Design as a Women's Studies Method.

    ERIC Educational Resources Information Center

    Trobian, Helen R.

    Guided Design has great potential as a teaching/learning method for Women's Studies courses. The Guided Design process is organized around the learner's efforts to come up with solutions to a series of carefully designed, open-ended problems. The problems are selected by the teacher according to the skills and subject matter to be learned. The…

  12. Television advertisement format and the provision of risk information about prescription drug products.

    PubMed

    Glinert, Lewis H; Schommer, Jon C

    2005-06-01

    Considerable attention has been afforded to analyzing the content of and assessing consumers' reaction to print direct-to-consumer drug ads, but not so for televised ads. To determine whether advertisements with different risk severity and risk presentation would significantly affect viewers' (1) recall of information contained in the advertisement, (2) evaluation of the advertisement, and (3) perceptions of the advertised product's risks. Data were collected from a sample of 135 first-year pharmacy students at a Midwestern college of pharmacy. After viewing 1 of the 6 advertisements designed for this study, participants were asked to complete a self-administered survey. Chi-square and analysis of variance were used to analyze the data. A 2x3 between subjects design was used to test the effects of 2 levels of risk severity (high- vs low-risk severity) and 3 levels of risk presentation (original ad containing integrated risk message, deintegrated risk message/dual modality using male voice-over, deintegrated risk message/dual modality using female voice-over). Results of analysis of variance procedures revealed that deintegrating risk information by placing it at the end of the advertisement and the use of captions in addition to oral messages (dual modality) (1) improved the recall of general and specific side effect information, (2) led to a perception that the advertisement had greater informational content, (3) resulted in lower Advertisement Distraction, and (4) lessened cognitive and affective aspects of information overload for the advertisement containing the high-risk severity medication. However, this pattern of findings was not found for the low-risk severity medication. Alternative methods for presenting risk information in direct-to-consumer ads affected some aspects of information recall and advertisement evaluation, but were not shown to affect risk perceptions regarding the advertised products.

  13. Fatalistic responses to different types of genetic risk information: exploring the role of self-malleability.

    PubMed

    Claassen, Liesbeth; Henneman, Lidewij; De Vet, Riekie; Knol, Dirk; Marteau, Theresa; Timmermans, Danielle

    2010-02-01

    Providing people with genetic risk information may induce a sense of fatalism, the belief that little can be done to reduce the risk. We postulated that fatalism is a function of health risk information and individual differences in self-perception. DNA-based risk information was hypothesised to generate more fatalism than risk information based on family history or non-genetic risk information. Moreover, people who view themselves as more rather than less able to change self-attributes were hypothesised to respond least fatalistically. Factor analyses in separate samples were used to construct a five-item 'Malleability of self' measure. Predictive validity of the measure was tested using a within-subjects analogue design. Participants responded to three scenario vignettes in which they were informed of an increased risk of cardiovascular disease (CVD). In Scenario 1, risk was ascertained by DNA testing, family history and cholesterol testing; in Scenario 2, it was ascertained by family history and cholesterol testing; in Scenario 3, risk was ascertained by cholesterol testing alone. Scenario 1 was associated with least perceived control over cholesterol level and CVD risk. People who viewed themselves as more able to change self-attributes experienced more control in all three scenarios.

  14. Methods for combinatorial and parallel library design.

    PubMed

    Schnur, Dora M; Beno, Brett R; Tebben, Andrew J; Cavallaro, Cullen

    2011-01-01

    Diversity has historically played a critical role in design of combinatorial libraries, screening sets and corporate collections for lead discovery. Large library design dominated the field in the 1990s with methods ranging anywhere from purely arbitrary through property based reagent selection to product based approaches. In recent years, however, there has been a downward trend in library size. This was due to increased information about the desirable targets gleaned from the genomics revolution and to the ever growing availability of target protein structures from crystallography and homology modeling. Creation of libraries directed toward families of receptors such as GPCRs, kinases, nuclear hormone receptors, proteases, etc., replaced the generation of libraries based primarily on diversity while single target focused library design has remained an important objective. Concurrently, computing grids and cpu clusters have facilitated the development of structure based tools that screen hundreds of thousands of molecules. Smaller "smarter" combinatorial and focused parallel libraries replaced those early un-focused large libraries in the twenty-first century drug design paradigm. While diversity still plays a role in lead discovery, the focus of current library design methods has shifted to receptor based methods, scaffold hopping/bio-isostere searching, and a much needed emphasis on synthetic feasibility. Methods such as "privileged substructures based design" and pharmacophore based design still are important methods for parallel and small combinatorial library design. This chapter discusses some of the possible design methods and presents examples where they are available.

  15. Product Development by Design Navigation Method

    NASA Astrophysics Data System (ADS)

    Nakazawa, Hiromu

    Manufacturers must be able to develop new products within a specified time period. This paper discusses a method for developing high performance products from a limited number of experiments, utilizing the concept of “function error”. Unlike conventional methods where the sequence of design, prototyping and experiment must be repeated several times, the proposed method can determine optimal design values directly from experimental data obtained from the first prototype. The theoretical basis of the method is presented, then its effectiveness proven by applying it to design an extrusion machine and a CNC lathe.

  16. Mixed Method Designs in Implementation Research

    PubMed Central

    Aarons, Gregory A.; Horwitz, Sarah; Chamberlain, Patricia; Hurlburt, Michael; Landsverk, John

    2010-01-01

    This paper describes the application of mixed method designs in implementation research in 22 mental health services research studies published in peer-reviewed journals over the last 5 years. Our analyses revealed 7 different structural arrangements of qualitative and quantitative methods, 5 different functions of mixed methods, and 3 different ways of linking quantitative and qualitative data together. Complexity of design was associated with number of aims or objectives, study context, and phase of implementation examined. The findings provide suggestions for the use of mixed method designs in implementation research. PMID:20967495

  17. Mixed method designs in implementation research.

    PubMed

    Palinkas, Lawrence A; Aarons, Gregory A; Horwitz, Sarah; Chamberlain, Patricia; Hurlburt, Michael; Landsverk, John

    2011-01-01

    This paper describes the application of mixed method designs in implementation research in 22 mental health services research studies published in peer-reviewed journals over the last 5 years. Our analyses revealed 7 different structural arrangements of qualitative and quantitative methods, 5 different functions of mixed methods, and 3 different ways of linking quantitative and qualitative data together. Complexity of design was associated with number of aims or objectives, study context, and phase of implementation examined. The findings provide suggestions for the use of mixed method designs in implementation research.

  18. Analyses to support development of risk-informed separation distances for hydrogen codes and standards.

    SciTech Connect

    LaChance, Jeffrey L.; Houf, William G.; Fluer, Inc., Paso Robels, CA; Fluer, Larry; Middleton, Bobby

    2009-03-01

    The development of a set of safety codes and standards for hydrogen facilities is necessary to ensure they are designed and operated safely. To help ensure that a hydrogen facility meets an acceptable level of risk, code and standard development organizations are tilizing risk-informed concepts in developing hydrogen codes and standards.

  19. Should the model for risk-informed regulation be game theory rather than decision theory?

    PubMed

    Bier, Vicki M; Lin, Shi-Woei

    2013-02-01

    Risk analysts frequently view the regulation of risks as being largely a matter of decision theory. According to this view, risk analysis methods provide information on the likelihood and severity of various possible outcomes; this information should then be assessed using a decision-theoretic approach (such as cost/benefit analysis) to determine whether the risks are acceptable, and whether additional regulation is warranted. However, this view ignores the fact that in many industries (particularly industries that are technologically sophisticated and employ specialized risk and safety experts), risk analyses may be done by regulated firms, not by the regulator. Moreover, those firms may have more knowledge about the levels of safety at their own facilities than the regulator does. This creates a situation in which the regulated firm has both the opportunity-and often also the motive-to provide inaccurate (in particular, favorably biased) risk information to the regulator, and hence the regulator has reason to doubt the accuracy of the risk information provided by regulated parties. Researchers have argued that decision theory is capable of dealing with many such strategic interactions as well as game theory can. This is especially true in two-player, two-stage games in which the follower has a unique best strategy in response to the leader's strategy, as appears to be the case in the situation analyzed in this article. However, even in such cases, we agree with Cox that game-theoretic methods and concepts can still be useful. In particular, the tools of mechanism design, and especially the revelation principle, can simplify the analysis of such games because the revelation principle provides rigorous assurance that it is sufficient to analyze only games in which licensees truthfully report their risk levels, making the problem more manageable. Without that, it would generally be necessary to consider much more complicated forms of strategic behavior (including

  20. LCR method: road map for passive design

    SciTech Connect

    Morris, W.S.

    1983-05-01

    Choosing a design tool to estimate the performance of passive solar houses is discussed. One technique is the Load Collector Ratio (LCR) method. This method allows the solar designer to get quick performance estimates plus a feeling for the results that would be obtained by taking a different approach. How to use the LCR method and the results to be obtained from using it are discussed.

  1. Applications of a transonic wing design method

    NASA Technical Reports Server (NTRS)

    Campbell, Richard L.; Smith, Leigh A.

    1989-01-01

    A method for designing wings and airfoils at transonic speeds using a predictor/corrector approach was developed. The procedure iterates between an aerodynamic code, which predicts the flow about a given geometry, and the design module, which compares the calculated and target pressure distributions and modifies the geometry using an algorithm that relates differences in pressure to a change in surface curvature. The modular nature of the design method makes it relatively simple to couple it to any analysis method. The iterative approach allows the design process and aerodynamic analysis to converge in parallel, significantly reducing the time required to reach a final design. Viscous and static aeroelastic effects can also be accounted for during the design or as a post-design correction. Results from several pilot design codes indicated that the method accurately reproduced pressure distributions as well as the coordinates of a given airfoil or wing by modifying an initial contour. The codes were applied to supercritical as well as conventional airfoils, forward- and aft-swept transport wings, and moderate-to-highly swept fighter wings. The design method was found to be robust and efficient, even for cases having fairly strong shocks.

  2. Impeller blade design method for centrifugal compressors

    NASA Technical Reports Server (NTRS)

    Jansen, W.; Kirschner, A. M.

    1974-01-01

    The design of a centrifugal impeller with blades that are aerodynamically efficient, easy to manufacture, and mechanically sound is discussed. The blade design method described here satisfies the first two criteria and with a judicious choice of certain variables will also satisfy stress considerations. The blade shape is generated by specifying surface velocity distributions and consists of straight-line elements that connect points at hub and shroud. The method may be used to design radially elemented and backward-swept blades. The background, a brief account of the theory, and a sample design are described.

  3. Model reduction methods for control design

    NASA Technical Reports Server (NTRS)

    Dunipace, K. R.

    1988-01-01

    Several different model reduction methods are developed and detailed implementation information is provided for those methods. Command files to implement the model reduction methods in a proprietary control law analysis and design package are presented. A comparison and discussion of the various reduction techniques is included.

  4. Climate Risk Informed Decision Analysis (CRIDA): A novel practical guidance for Climate Resilient Investments and Planning

    NASA Astrophysics Data System (ADS)

    Jeuken, Ad; Mendoza, Guillermo; Matthews, John; Ray, Patrick; Haasnoot, Marjolijn; Gilroy, Kristin; Olsen, Rolf; Kucharski, John; Stakhiv, Gene; Cushing, Janet; Brown, Casey

    2016-04-01

    over time. They are part of the Dutch adaptive planning approach Adaptive Delta Management, executed and develop by the Dutch Delta program. Both decision scaling and adaptation pathways have been piloted in studies worldwide. The objective of CRIDA is to mainstream effective climate adaptation for professional water managers. The CRIDA publication, due in april 2016, follows the generic water design planning design cycle. At each step, CRIDA describes stepwise guidance for incorporating climate robustness: problem definition, stress test, alternatives formulation and recommendation, evaluation and selection. In the presentation the origin, goal, steps and practical tools available at each step of CRIDA will be explained. In two other abstracts ("Climate Risk Informed Decision Analysis: A Hypothetical Application to the Waas Region" by Gilroy et al., "The Application of Climate Risk Informed Decision Analysis to the Ioland Water Treatment Plant in Lusaka, Zambia, by Kucharski et al.), the application of CRIDA to cases is explained

  5. Mixed Methods Research Designs in Counseling Psychology

    ERIC Educational Resources Information Center

    Hanson, William E.; Creswell, John W.; Clark, Vicki L. Plano; Petska, Kelly S.; Creswell, David J.

    2005-01-01

    With the increased popularity of qualitative research, researchers in counseling psychology are expanding their methodologies to include mixed methods designs. These designs involve the collection, analysis, and integration of quantitative and qualitative data in a single or multiphase study. This article presents an overview of mixed methods…

  6. Mixed Methods Research Designs in Counseling Psychology

    ERIC Educational Resources Information Center

    Hanson, William E.; Creswell, John W.; Clark, Vicki L. Plano; Petska, Kelly S.; Creswell, David J.

    2005-01-01

    With the increased popularity of qualitative research, researchers in counseling psychology are expanding their methodologies to include mixed methods designs. These designs involve the collection, analysis, and integration of quantitative and qualitative data in a single or multiphase study. This article presents an overview of mixed methods…

  7. Airbreathing hypersonic vehicle design and analysis methods

    NASA Technical Reports Server (NTRS)

    Lockwood, Mary Kae; Petley, Dennis H.; Hunt, James L.; Martin, John G.

    1996-01-01

    The design, analysis, and optimization of airbreathing hypersonic vehicles requires analyses involving many highly coupled disciplines at levels of accuracy exceeding those traditionally considered in a conceptual or preliminary-level design. Discipline analysis methods including propulsion, structures, thermal management, geometry, aerodynamics, performance, synthesis, sizing, closure, and cost are discussed. Also, the on-going integration of these methods into a working environment, known as HOLIST, is described.

  8. Iterative methods for design sensitivity analysis

    NASA Technical Reports Server (NTRS)

    Belegundu, A. D.; Yoon, B. G.

    1989-01-01

    A numerical method is presented for design sensitivity analysis, using an iterative-method reanalysis of the structure generated by a small perturbation in the design variable; a forward-difference scheme is then employed to obtain the approximate sensitivity. Algorithms are developed for displacement and stress sensitivity, as well as for eignevalues and eigenvector sensitivity, and the iterative schemes are modified so that the coefficient matrices are constant and therefore decomposed only once.

  9. Impact of risk information on perceived colorectal cancer risk: a randomized trial.

    PubMed

    Robb, Kathryn A; Campbell, John; Evans, Philip; Miles, Anne; Wardle, Jane

    2008-09-01

    The study sought to modify comparative optimism about colorectal cancer in a community sample using a method of providing risk information found to be effective in a laboratory setting. The 3185 adults from General Practice lists were randomized to three groups: (1) control--no information; (2) risk information leaflet; (3) risk and screening information leaflet. Significant comparative optimism and high numeric estimates of absolute risk were found. Risk factor information did not reduce optimistic beliefs nor modify estimates of risk. Interest in screening was high overall and not influenced by the information. Comparatively optimistic risk perceptions appear resistant to change in community settings.

  10. Risk-informed inservice test activities at the NRC

    SciTech Connect

    Fischer, D.; Cheok, M.; Hsia, A.

    1996-12-01

    The operational readiness of certain safety-related components is vital to the safe operation of nuclear power plants. Inservice testing (IST) is one of the mechanisms used by licensees to ensure this readiness. In the past, the type and frequency of IST have been based on the collective best judgment of the NRC and industry in an ASME Code consensus process and NRC rulemaking process. Furthermore, IST requirements have not explicitly considered unique component and system designs and contribution to overall plant risk. Because of the general nature of ASME Code test requirements and non-reliance on risk estimates, current IST requirements may not adequately emphasize testing those components that are most important to safety and may overly emphasize testing of less safety significant components. Nuclear power plant licensees are currently interested in optimizing testing by applying resources in more safety significant areas and, where appropriate, reducing measures in less safety-significant areas. They are interested in maintaining system availability and reducing overall maintenance costs in ways that do not adversely affect safety. The NRC has been interested in using probabilistic, as an adjunct to deterministic, techniques to help define the scope, type and frequency of IST. The development of risk-informed IST programs has the potential to optimize the use of NRC and industry resources without adverse affect on safety.

  11. A Method for Designing Conforming Folding Propellers

    NASA Technical Reports Server (NTRS)

    Litherland, Brandon L.; Patterson, Michael D.; Derlaga, Joseph M.; Borer, Nicholas K.

    2017-01-01

    As the aviation vehicle design environment expands due to the in flux of new technologies, new methods of conceptual design and modeling are required in order to meet the customer's needs. In the case of distributed electric propulsion (DEP), the use of high-lift propellers upstream of the wing leading edge augments lift at low speeds enabling smaller wings with sufficient takeoff and landing performance. During cruise, however, these devices would normally contribute significant drag if left in a fixed or windmilling arrangement. Therefore, a design that stows the propeller blades is desirable. In this paper, we present a method for designing folding-blade configurations that conform to the nacelle surface when stowed. These folded designs maintain performance nearly identical to their straight, non-folding blade counterparts.

  12. Development of a hydraulic turbine design method

    NASA Astrophysics Data System (ADS)

    Kassanos, Ioannis; Anagnostopoulos, John; Papantonis, Dimitris

    2013-10-01

    In this paper a hydraulic turbine parametric design method is presented which is based on the combination of traditional methods and parametric surface modeling techniques. The blade of the turbine runner is described using Bezier surfaces for the definition of the meridional plane as well as the blade angle distribution, and a thickness distribution applied normal to the mean blade surface. In this way, it is possible to define parametrically the whole runner using a relatively small number of design parameters, compared to conventional methods. The above definition is then combined with a commercial CFD software and a stochastic optimization algorithm towards the development of an automated design optimization procedure. The process is demonstrated with the design of a Francis turbine runner.

  13. Preliminary aerothermodynamic design method for hypersonic vehicles

    NASA Technical Reports Server (NTRS)

    Harloff, G. J.; Petrie, S. L.

    1987-01-01

    Preliminary design methods are presented for vehicle aerothermodynamics. Predictions are made for Shuttle orbiter, a Mach 6 transport vehicle and a high-speed missile configuration. Rapid and accurate methods are discussed for obtaining aerodynamic coefficients and heat transfer rates for laminar and turbulent flows for vehicles at high angles of attack and hypersonic Mach numbers.

  14. Multidisciplinary Optimization Methods for Aircraft Preliminary Design

    NASA Technical Reports Server (NTRS)

    Kroo, Ilan; Altus, Steve; Braun, Robert; Gage, Peter; Sobieski, Ian

    1994-01-01

    This paper describes a research program aimed at improved methods for multidisciplinary design and optimization of large-scale aeronautical systems. The research involves new approaches to system decomposition, interdisciplinary communication, and methods of exploiting coarse-grained parallelism for analysis and optimization. A new architecture, that involves a tight coupling between optimization and analysis, is intended to improve efficiency while simplifying the structure of multidisciplinary, computation-intensive design problems involving many analysis disciplines and perhaps hundreds of design variables. Work in two areas is described here: system decomposition using compatibility constraints to simplify the analysis structure and take advantage of coarse-grained parallelism; and collaborative optimization, a decomposition of the optimization process to permit parallel design and to simplify interdisciplinary communication requirements.

  15. Multidisciplinary Optimization Methods for Preliminary Design

    NASA Technical Reports Server (NTRS)

    Korte, J. J.; Weston, R. P.; Zang, T. A.

    1997-01-01

    An overview of multidisciplinary optimization (MDO) methodology and two applications of this methodology to the preliminary design phase are presented. These applications are being undertaken to improve, develop, validate and demonstrate MDO methods. Each is presented to illustrate different aspects of this methodology. The first application is an MDO preliminary design problem for defining the geometry and structure of an aerospike nozzle of a linear aerospike rocket engine. The second application demonstrates the use of the Framework for Interdisciplinary Design Optimization (FIDO), which is a computational environment system, by solving a preliminary design problem for a High-Speed Civil Transport (HSCT). The two sample problems illustrate the advantages to performing preliminary design with an MDO process.

  16. Analysis Method for Quantifying Vehicle Design Goals

    NASA Technical Reports Server (NTRS)

    Fimognari, Peter; Eskridge, Richard; Martin, Adam; Lee, Michael

    2007-01-01

    A document discusses a method for using Design Structure Matrices (DSM), coupled with high-level tools representing important life-cycle parameters, to comprehensively conceptualize a flight/ground space transportation system design by dealing with such variables as performance, up-front costs, downstream operations costs, and reliability. This approach also weighs operational approaches based on their effect on upstream design variables so that it is possible to readily, yet defensively, establish linkages between operations and these upstream variables. To avoid the large range of problems that have defeated previous methods of dealing with the complex problems of transportation design, and to cut down the inefficient use of resources, the method described in the document identifies those areas that are of sufficient promise and that provide a higher grade of analysis for those issues, as well as the linkages at issue between operations and other factors. Ultimately, the system is designed to save resources and time, and allows for the evolution of operable space transportation system technology, and design and conceptual system approach targets.

  17. Axisymmetric inlet minimum weight design method

    NASA Technical Reports Server (NTRS)

    Nadell, Shari-Beth

    1995-01-01

    An analytical method for determining the minimum weight design of an axisymmetric supersonic inlet has been developed. The goal of this method development project was to improve the ability to predict the weight of high-speed inlets in conceptual and preliminary design. The initial model was developed using information that was available from inlet conceptual design tools (e.g., the inlet internal and external geometries and pressure distributions). Stiffened shell construction was assumed. Mass properties were computed by analyzing a parametric cubic curve representation of the inlet geometry. Design loads and stresses were developed at analysis stations along the length of the inlet. The equivalent minimum structural thicknesses for both shell and frame structures required to support the maximum loads produced by various load conditions were then determined. Preliminary results indicated that inlet hammershock pressures produced the critical design load condition for a significant portion of the inlet. By improving the accuracy of inlet weight predictions, the method will improve the fidelity of propulsion and vehicle design studies and increase the accuracy of weight versus cost studies.

  18. Optimization methods applied to hybrid vehicle design

    NASA Technical Reports Server (NTRS)

    Donoghue, J. F.; Burghart, J. H.

    1983-01-01

    The use of optimization methods as an effective design tool in the design of hybrid vehicle propulsion systems is demonstrated. Optimization techniques were used to select values for three design parameters (battery weight, heat engine power rating and power split between the two on-board energy sources) such that various measures of vehicle performance (acquisition cost, life cycle cost and petroleum consumption) were optimized. The apporach produced designs which were often significant improvements over hybrid designs already reported on in the literature. The principal conclusions are as follows. First, it was found that the strategy used to split the required power between the two on-board energy sources can have a significant effect on life cycle cost and petroleum consumption. Second, the optimization program should be constructed so that performance measures and design variables can be easily changed. Third, the vehicle simulation program has a significant effect on the computer run time of the overall optimization program; run time can be significantly reduced by proper design of the types of trips the vehicle takes in a one year period. Fourth, care must be taken in designing the cost and constraint expressions which are used in the optimization so that they are relatively smooth functions of the design variables. Fifth, proper handling of constraints on battery weight and heat engine rating, variables which must be large enough to meet power demands, is particularly important for the success of an optimization study. Finally, the principal conclusion is that optimization methods provide a practical tool for carrying out the design of a hybrid vehicle propulsion system.

  19. Novel Methods for Electromagnetic Simulation and Design

    DTIC Science & Technology

    2016-08-03

    AFRL-AFOSR-VA-TR-2016-0272 NOVEL METHODS FOR ELECTROMAGNETIC SIMULATION AND DESIGN Leslie Greengard NEW YORK UNIVERSITY 70 WASHINGTON SQUARE S NEW...METHODS FOR ELECTROMAGNETIC SIMULATION AND DESIGN 5a.  CONTRACT NUMBER 5b.  GRANT NUMBER FA9550-10-1-0180 5c.  PROGRAM ELEMENT NUMBER 61102F 6. AUTHOR(S... electromagnetic scattering in realistic environments involving complex geometry. During the six year performance period (including a one-year no cost extension

  20. Computer-Aided Drug Design Methods.

    PubMed

    Yu, Wenbo; MacKerell, Alexander D

    2017-01-01

    Computational approaches are useful tools to interpret and guide experiments to expedite the antibiotic drug design process. Structure-based drug design (SBDD) and ligand-based drug design (LBDD) are the two general types of computer-aided drug design (CADD) approaches in existence. SBDD methods analyze macromolecular target 3-dimensional structural information, typically of proteins or RNA, to identify key sites and interactions that are important for their respective biological functions. Such information can then be utilized to design antibiotic drugs that can compete with essential interactions involving the target and thus interrupt the biological pathways essential for survival of the microorganism(s). LBDD methods focus on known antibiotic ligands for a target to establish a relationship between their physiochemical properties and antibiotic activities, referred to as a structure-activity relationship (SAR), information that can be used for optimization of known drugs or guide the design of new drugs with improved activity. In this chapter, standard CADD protocols for both SBDD and LBDD will be presented with a special focus on methodologies and targets routinely studied in our laboratory for antibiotic drug discoveries.

  1. Standardized Radiation Shield Design Methods: 2005 HZETRN

    NASA Technical Reports Server (NTRS)

    Wilson, John W.; Tripathi, Ram K.; Badavi, Francis F.; Cucinotta, Francis A.

    2006-01-01

    Research committed by the Langley Research Center through 1995 resulting in the HZETRN code provides the current basis for shield design methods according to NASA STD-3000 (2005). With this new prominence, the database, basic numerical procedures, and algorithms are being re-examined with new methods of verification and validation being implemented to capture a well defined algorithm for engineering design processes to be used in this early development phase of the Bush initiative. This process provides the methodology to transform the 1995 HZETRN research code into the 2005 HZETRN engineering code to be available for these early design processes. In this paper, we will review the basic derivations including new corrections to the codes to insure improved numerical stability and provide benchmarks for code verification.

  2. MAST Propellant and Delivery System Design Methods

    NASA Technical Reports Server (NTRS)

    Nadeem, Uzair; Mc Cleskey, Carey M.

    2015-01-01

    A Mars Aerospace Taxi (MAST) concept and propellant storage and delivery case study is undergoing investigation by NASA's Element Design and Architectural Impact (EDAI) design and analysis forum. The MAST lander concept envisions landing with its ascent propellant storage tanks empty and supplying these reusable Mars landers with propellant that is generated and transferred while on the Mars surface. The report provides an overview of the data derived from modeling between different methods of propellant line routing (or "lining") and differentiate the resulting design and operations complexity of fluid and gaseous paths based on a given set of fluid sources and destinations. The EDAI team desires a rough-order-magnitude algorithm for estimating the lining characteristics (i.e., the plumbing mass and complexity) associated different numbers of vehicle propellant sources and destinations. This paper explored the feasibility of preparing a mathematically sound algorithm for this purpose, and offers a method for the EDAI team to implement.

  3. Case study: design? Method? Or comprehensive strategy?

    PubMed

    Jones, Colin; Lyons, Christina

    2004-01-01

    As the case study approach gains popularity in nursing research, questions arise with regard to what it exactly is, and where it appears to fit paradigmatically. Is it a method, a design, are such distinctions important? Colin Jones and Christina Lyons review some of the key issues, with specific emphasis on the use of case study within an interpretevist philosophy.

  4. Financial methods for waterflooding injectate design

    DOEpatents

    Heneman, Helmuth J.; Brady, Patrick V.

    2017-08-08

    A method of selecting an injectate for recovering liquid hydrocarbons from a reservoir includes designing a plurality of injectates, calculating a net present value of each injectate, and selecting a candidate injectate based on the net present value. For example, the candidate injectate may be selected to maximize the net present value of a waterflooding operation.

  5. Statistical Methods in Algorithm Design and Analysis.

    ERIC Educational Resources Information Center

    Weide, Bruce W.

    The use of statistical methods in the design and analysis of discrete algorithms is explored. The introductory chapter contains a literature survey and background material on probability theory. In Chapter 2, probabilistic approximation algorithms are discussed with the goal of exposing and correcting some oversights in previous work. Chapter 3…

  6. An optimisation method for complex product design

    NASA Astrophysics Data System (ADS)

    Li, Ni; Yi, Wenqing; Bi, Zhuming; Kong, Haipeng; Gong, Guanghong

    2013-11-01

    Designing a complex product such as an aircraft usually requires both qualitative and quantitative data and reasoning. To assist the design process, a critical issue is how to represent qualitative data and utilise it in the optimisation. In this study, a new method is proposed for the optimal design of complex products: to make the full use of available data, information and knowledge, qualitative reasoning is integrated into the optimisation process. The transformation and fusion of qualitative and qualitative data are achieved via the fuzzy sets theory and a cloud model. To shorten the design process, parallel computing is implemented to solve the formulated optimisation problems. A parallel adaptive hybrid algorithm (PAHA) has been proposed. The performance of the new algorithm has been verified by a comparison with the results from PAHA and two other existing algorithms. Further, PAHA has been applied to determine the shape parameters of an aircraft model for aerodynamic optimisation purpose.

  7. Approaches to cancer assessment in EPA's Integrated Risk Information System

    SciTech Connect

    Gehlhaus, Martin W.; Gift, Jeffrey S.; Hogan, Karen A.; Kopylev, Leonid; Schlosser, Paul M.; Kadry, Abdel-Razak

    2011-07-15

    The U.S. Environmental Protection Agency's (EPA) Integrated Risk Information System (IRIS) Program develops assessments of health effects that may result from chronic exposure to chemicals in the environment. The IRIS database contains more than 540 assessments. When supported by available data, IRIS assessments provide quantitative analyses of carcinogenic effects. Since publication of EPA's 2005 Guidelines for Carcinogen Risk Assessment, IRIS cancer assessments have implemented new approaches recommended in these guidelines and expanded the use of complex scientific methods to perform quantitative dose-response assessments. Two case studies of the application of the mode of action framework from the 2005 Cancer Guidelines are presented in this paper. The first is a case study of 1,2,3-trichloropropane, as an example of a chemical with a mutagenic mode of carcinogenic action thus warranting the application of age-dependent adjustment factors for early-life exposure; the second is a case study of ethylene glycol monobutyl ether, as an example of a chemical with a carcinogenic action consistent with a nonlinear extrapolation approach. The use of physiologically based pharmacokinetic (PBPK) modeling to quantify interindividual variability and account for human parameter uncertainty as part of a quantitative cancer assessment is illustrated using a case study involving probabilistic PBPK modeling for dichloromethane. We also discuss statistical issues in assessing trends and model fit for tumor dose-response data, analysis of the combined risk from multiple types of tumors, and application of life-table methods for using human data to derive cancer risk estimates. These issues reflect the complexity and challenges faced in assessing the carcinogenic risks from exposure to environmental chemicals, and provide a view of the current trends in IRIS carcinogenicity risk assessment.

  8. Acoustic Treatment Design Scaling Methods. Phase 2

    NASA Technical Reports Server (NTRS)

    Clark, L. (Technical Monitor); Parrott, T. (Technical Monitor); Jones, M. (Technical Monitor); Kraft, R. E.; Yu, J.; Kwan, H. W.; Beer, B.; Seybert, A. F.; Tathavadekar, P.

    2003-01-01

    The ability to design, build and test miniaturized acoustic treatment panels on scale model fan rigs representative of full scale engines provides not only cost-savings, but also an opportunity to optimize the treatment by allowing multiple tests. To use scale model treatment as a design tool, the impedance of the sub-scale liner must be known with confidence. This study was aimed at developing impedance measurement methods for high frequencies. A normal incidence impedance tube method that extends the upper frequency range to 25,000 Hz. without grazing flow effects was evaluated. The free field method was investigated as a potential high frequency technique. The potential of the two-microphone in-situ impedance measurement method was evaluated in the presence of grazing flow. Difficulties in achieving the high frequency goals were encountered in all methods. Results of developing a time-domain finite difference resonator impedance model indicated that a re-interpretation of the empirical fluid mechanical models used in the frequency domain model for nonlinear resistance and mass reactance may be required. A scale model treatment design that could be tested on the Universal Propulsion Simulator vehicle was proposed.

  9. 3. 6 simplified methods for design

    SciTech Connect

    Nickell, R.E.; Yahr, G.T.

    1981-01-01

    Simplified design analysis methods for elevated temperature construction are classified and reviewed. Because the major impetus for developing elevated temperature design methodology during the past ten years has been the LMFBR program, considerable emphasis is placed upon results from this source. The operating characteristics of the LMFBR are such that cycles of severe transient thermal stresses can be interspersed with normal elevated temperature operational periods of significant duration, leading to a combination of plastic and creep deformation. The various simplified methods are organized into two general categories, depending upon whether it is the material, or constitutive, model that is reduced, or the geometric modeling that is simplified. Because the elastic representation of material behavior is so prevalent, an entire section is devoted to elastic analysis methods. Finally, the validation of the simplified procedures is discussed.

  10. Reliability Methods for Shield Design Process

    NASA Technical Reports Server (NTRS)

    Tripathi, R. K.; Wilson, J. W.

    2002-01-01

    Providing protection against the hazards of space radiation is a major challenge to the exploration and development of space. The great cost of added radiation shielding is a potential limiting factor in deep space operations. In this enabling technology, we have developed methods for optimized shield design over multi-segmented missions involving multiple work and living areas in the transport and duty phase of space missions. The total shield mass over all pieces of equipment and habitats is optimized subject to career dose and dose rate constraints. An important component of this technology is the estimation of two most commonly identified uncertainties in radiation shield design, the shielding properties of materials used and the understanding of the biological response of the astronaut to the radiation leaking through the materials into the living space. The largest uncertainty, of course, is in the biological response to especially high charge and energy (HZE) ions of the galactic cosmic rays. These uncertainties are blended with the optimization design procedure to formulate reliability-based methods for shield design processes. The details of the methods will be discussed.

  11. A novel method to design flexible URAs

    NASA Astrophysics Data System (ADS)

    Lang, Haitao; Liu, Liren; Yang, Qingguo

    2007-05-01

    Aperture patterns play a vital role in coded aperture imaging (CAI) applications. In recent years, many approaches were presented to design optimum or near-optimum aperture patterns. Uniformly redundant arrays (URAs) are, undoubtedly, the most successful for constant sidelobe of their periodic autocorrelation function. Unfortunately, the existing methods can only be used to design URAs with a limited number of array sizes and fixed autocorrelation sidelobe-to-peak ratios. In this paper, we present a novel method to design more flexible URAs. Our approach is based on a searching program driven by DIRECT, a global optimization algorithm. We transform the design question to a mathematical model, based on the DIRECT algorithm, which is advantageous for computer implementation. By changing determinative conditions, we obtain two kinds of types of URAs, including the filled URAs which can be constructed by existing methods and the sparse URAs which have never been mentioned by other authors as far as we know. Finally, we carry out an experiment to demonstrate the imaging performance of the sparse URAs.

  12. Optimum Design Methods for Structural Sandwich Panels

    DTIC Science & Technology

    1988-01-01

    Security ClassificatioN~ Optimum Design Methods for Structural Sandwich Panels M 4, l 12. PERSONAL AUTHOR(S) Gibson, Lorna J. 113a. TYPE OF REPORT 13b...The largest value of GrE , for the 320 kg/m 3 foam for which the crack propagated through the adhesive, corresponds to the surface energy of the...Introduction , The goal of this part of the pro.ect is to find the minimum weight design of a foam core sandwich beam fora given strernth. The optimum value

  13. Optimization methods for alternative energy system design

    NASA Astrophysics Data System (ADS)

    Reinhardt, Michael Henry

    An electric vehicle heating system and a solar thermal coffee dryer are presented as case studies in alternative energy system design optimization. Design optimization tools are compared using these case studies, including linear programming, integer programming, and fuzzy integer programming. Although most decision variables in the designs of alternative energy systems are generally discrete (e.g., numbers of photovoltaic modules, thermal panels, layers of glazing in windows), the literature shows that the optimization methods used historically for design utilize continuous decision variables. Integer programming, used to find the optimal investment in conservation measures as a function of life cycle cost of an electric vehicle heating system, is compared to linear programming, demonstrating the importance of accounting for the discrete nature of design variables. The electric vehicle study shows that conservation methods similar to those used in building design, that reduce the overall UA of a 22 ft. electric shuttle bus from 488 to 202 (Btu/hr-F), can eliminate the need for fossil fuel heating systems when operating in the northeast United States. Fuzzy integer programming is presented as a means of accounting for imprecise design constraints such as being environmentally friendly in the optimization process. The solar thermal coffee dryer study focuses on a deep-bed design using unglazed thermal collectors (UTC). Experimental data from parchment coffee drying are gathered, including drying constants and equilibrium moisture. In this case, fuzzy linear programming is presented as a means of optimizing experimental procedures to produce the most information under imprecise constraints. Graphical optimization is used to show that for every 1 m2 deep-bed dryer, of 0.4 m depth, a UTC array consisting of 5, 1.1 m 2 panels, and a photovoltaic array consisting of 1, 0.25 m 2 panels produces the most dry coffee per dollar invested in the system. In general this study

  14. Risk-informed radioactive waste classification and reclassification.

    PubMed

    Croff, Allen G

    2006-11-01

    Radioactive waste classification systems have been developed to allow wastes having similar hazards to be grouped for purposes of storage, treatment, packaging, transportation, and/or disposal. As recommended in the National Council on Radiation Protection and Measurements' Report No. 139, Risk-Based Classification of Radioactive and Hazardous Chemical Wastes, a preferred classification system would be based primarily on the health risks to the public that arise from waste disposal and secondarily on other attributes such as the near-term practicalities of managing a waste, i.e., the waste classification system would be risk informed. The current U.S. radioactive waste classification system is not risk informed because key definitions--especially that of high-level waste--are based on the source of the waste instead of its inherent characteristics related to risk. A second important reason for concluding the existing U.S. radioactive waste classification system is not risk informed is there are no general principles or provisions for exempting materials from being classified as radioactive waste which would then allow management without regard to its radioactivity. This paper elaborates the current system for classifying and reclassifying radioactive wastes in the United States, analyzes the extent to which the system is risk informed and the ramifications of its not being so, and provides observations on potential future direction of efforts to address shortcomings in the U.S. radioactive waste classification system as of 2004.

  15. Risk-informed separation distances for hydrogen gas storage facilities.

    SciTech Connect

    Houf, William G.; Merilo, Erik; Winters, William Stanley, Jr.; Dedrick, Daniel E.; Groethe, Mark; LaChance, Jeffrey L.; Ruggles, Adam James; Moen, Christopher D.; Schefer, Robert W.; Keller, Jay O.; Zhang, Yao; Evans, Gregory Herbert

    2010-09-01

    The use of risk information in establishing code and standard requirements enables: (1) An adequate and appropriate level of safety; and (2) Deployment of hydrogen facilities are as safe as gasoline facilities. This effort provides a template for clear and defensible regulations, codes, and standards that can enable international market transformation.

  16. Waterflooding injectate design systems and methods

    DOEpatents

    Brady, Patrick V.; Krumhansl, James L.

    2014-08-19

    A method of designing an injectate to be used in a waterflooding operation is disclosed. One aspect includes specifying data representative of chemical characteristics of a liquid hydrocarbon, a connate, and a reservoir rock, of a subterranean reservoir. Charged species at an interface of the liquid hydrocarbon are determined based on the specified data by evaluating at least one chemical reaction. Charged species at an interface of the reservoir rock are determined based on the specified data by evaluating at least one chemical reaction. An extent of surface complexation between the charged species at the interfaces of the liquid hydrocarbon and the reservoir rock is determined by evaluating at least one surface complexation reaction. The injectate is designed and is operable to decrease the extent of surface complexation between the charged species at interfaces of the liquid hydrocarbon and the reservoir rock. Other methods, apparatus, and systems are disclosed.

  17. Evolutionary optimization methods for accelerator design

    NASA Astrophysics Data System (ADS)

    Poklonskiy, Alexey A.

    Many problems from the fields of accelerator physics and beam theory can be formulated as optimization problems and, as such, solved using optimization methods. Despite growing efficiency of the optimization methods, the adoption of modern optimization techniques in these fields is rather limited. Evolutionary Algorithms (EAs) form a relatively new and actively developed optimization methods family. They possess many attractive features such as: ease of the implementation, modest requirements on the objective function, a good tolerance to noise, robustness, and the ability to perform a global search efficiently. In this work we study the application of EAs to problems from accelerator physics and beam theory. We review the most commonly used methods of unconstrained optimization and describe the GATool, evolutionary algorithm and the software package, used in this work, in detail. Then we use a set of test problems to assess its performance in terms of computational resources, quality of the obtained result, and the tradeoff between them. We justify the choice of GATool as a heuristic method to generate cutoff values for the COSY-GO rigorous global optimization package for the COSY Infinity scientific computing package. We design the model of their mutual interaction and demonstrate that the quality of the result obtained by GATool increases as the information about the search domain is refined, which supports the usefulness of this model. We Giscuss GATool's performance on the problems suffering from static and dynamic noise and study useful strategies of GATool parameter tuning for these and other difficult problems. We review the challenges of constrained optimization with EAs and methods commonly used to overcome them. We describe REPA, a new constrained optimization method based on repairing, in exquisite detail, including the properties of its two repairing techniques: REFIND and REPROPT. We assess REPROPT's performance on the standard constrained

  18. Quality by design compliant analytical method validation.

    PubMed

    Rozet, E; Ziemons, E; Marini, R D; Boulanger, B; Hubert, Ph

    2012-01-03

    The concept of quality by design (QbD) has recently been adopted for the development of pharmaceutical processes to ensure a predefined product quality. Focus on applying the QbD concept to analytical methods has increased as it is fully integrated within pharmaceutical processes and especially in the process control strategy. In addition, there is the need to switch from the traditional checklist implementation of method validation requirements to a method validation approach that should provide a high level of assurance of method reliability in order to adequately measure the critical quality attributes (CQAs) of the drug product. The intended purpose of analytical methods is directly related to the final decision that will be made with the results generated by these methods under study. The final aim for quantitative impurity assays is to correctly declare a substance or a product as compliant with respect to the corresponding product specifications. For content assays, the aim is similar: making the correct decision about product compliance with respect to their specification limits. It is for these reasons that the fitness of these methods should be defined, as they are key elements of the analytical target profile (ATP). Therefore, validation criteria, corresponding acceptance limits, and method validation decision approaches should be settled in accordance with the final use of these analytical procedures. This work proposes a general methodology to achieve this in order to align method validation within the QbD framework and philosophy. β-Expectation tolerance intervals are implemented to decide about the validity of analytical methods. The proposed methodology is also applied to the validation of analytical procedures dedicated to the quantification of impurities or active product ingredients (API) in drug substances or drug products, and its applicability is illustrated with two case studies.

  19. Methods for structural design at elevated temperatures

    NASA Technical Reports Server (NTRS)

    Ellison, A. M.; Jones, W. E., Jr.; Leimbach, K. R.

    1973-01-01

    A procedure which can be used to design elevated temperature structures is discussed. The desired goal is to have the same confidence in the structural integrity at elevated temperature as the factor of safety gives on mechanical loads at room temperature. Methods of design and analysis for creep, creep rupture, and creep buckling are presented. Example problems are included to illustrate the analytical methods. Creep data for some common structural materials are presented. Appendix B is description, user's manual, and listing for the creep analysis program. The program predicts time to a given creep or to creep rupture for a material subjected to a specified stress-temperature-time spectrum. Fatigue at elevated temperature is discussed. Methods of analysis for high stress-low cycle fatigue, fatigue below the creep range, and fatigue in the creep range are included. The interaction of thermal fatigue and mechanical loads is considered, and a detailed approach to fatigue analysis is given for structures operating below the creep range.

  20. Design analysis, robust methods, and stress classification

    SciTech Connect

    Bees, W.J.

    1993-01-01

    This special edition publication volume is comprised of papers presented at the 1993 ASME Pressure Vessels and Piping Conference, July 25--29, 1993 in Denver, Colorado. The papers were prepared for presentations in technical sessions developed under the auspices of the PVPD Committees on Computer Technology, Design and Analysis, Operations Applications and Components. The topics included are: Analysis of Pressure Vessels and Components; Expansion Joints; Robust Methods; Stress Classification; and Non-Linear Analysis. Individual papers have been processed separately for inclusion in the appropriate data bases.

  1. Block designs in method transfer experiments.

    PubMed

    Altan, Stan; Shoung, Jyh-Ming

    2008-01-01

    Method transfer is a part of the pharmaceutical development process in which an analytical (chemical) procedure developed in one laboratory (typically the research laboratory) is about to be adopted by one or more recipient laboratories (production or commercial operations). The objective is to show that the recipient laboratory is capable of performing the procedure in an acceptable manner. In the course of carrying out a method transfer, other questions may arise related to fixed or random factors of interest, such as analyst, apparatus, batch, supplier of analytical reagents, and so forth. Estimates of reproducibility and repeatability may also be of interest. This article focuses on the application of various block designs that have been found useful in the comprehensive study of method transfer beyond the laboratory effect alone. An equivalence approach to the comparison of laboratories can still be carried out on either the least squares means or subject-specific means of the laboratories to justify a method transfer or to compare analytical methods.

  2. Needs for Risk Informing Environmental Cleanup Decision Making - 13613

    SciTech Connect

    Zhu, Ming; Moorer, Richard

    2013-07-01

    This paper discusses the needs for risk informing decision making by the U.S. Department of Energy (DOE) Office of Environmental Management (EM). The mission of the DOE EM is to complete the safe cleanup of the environmental legacy brought about from the nation's five decades of nuclear weapons development and production and nuclear energy research. This work represents some of the most technically challenging and complex cleanup efforts in the world and is projected to require the investment of billions of dollars and several decades to complete. Quantitative assessments of health and environmental risks play an important role in work prioritization and cleanup decisions of these challenging environmental cleanup and closure projects. The risk assessments often involve evaluation of performance of integrated engineered barriers and natural systems over a period of hundreds to thousands of years, when subject to complex geo-environmental transformation processes resulting from remediation and disposal actions. The requirement of resource investments for the cleanup efforts and the associated technical challenges have subjected the EM program to continuous scrutiny by oversight entities. Recent DOE reviews recommended application of a risk-informed approach throughout the EM complex for improved targeting of resources. The idea behind this recommendation is that by using risk-informed approaches to prioritize work scope, the available resources can be best utilized to reduce environmental and health risks across the EM complex, while maintaining the momentum of the overall EM cleanup program at a sustainable level. In response to these recommendations, EM is re-examining its work portfolio and key decision making with risk insights for the major sites. This paper summarizes the review findings and recommendations from the DOE internal reviews, discusses the needs for risk informing the EM portfolio and makes an attempt to identify topics for R and D in integrated

  3. Computational and design methods for advanced imaging

    NASA Astrophysics Data System (ADS)

    Birch, Gabriel C.

    This dissertation merges the optical design and computational aspects of imaging systems to create novel devices that solve engineering problems in optical science and attempts to expand the solution space available to the optical designer. This dissertation is divided into two parts: the first discusses a new active illumination depth sensing modality, while the second part discusses a passive illumination system called plenoptic, or lightfield, imaging. The new depth sensing modality introduced in part one is called depth through controlled aberration. This technique illuminates a target with a known, aberrated projected pattern and takes an image using a traditional, unmodified imaging system. Knowing how the added aberration in the projected pattern changes as a function of depth, we are able to quantitatively determine depth of a series of points from the camera. A major advantage this method permits is the ability for illumination and imaging axes to be coincident. Plenoptic cameras capture both spatial and angular data simultaneously. This dissertation present a new set of parameters that permit the design and comparison of plenoptic devices outside the traditionally published plenoptic 1.0 and plenoptic 2.0 configurations. Additionally, a series of engineering advancements are presented, including full system raytraces of raw plenoptic images, Zernike compression techniques of raw image files, and non-uniform lenslet arrays to compensate for plenoptic system aberrations. Finally, a new snapshot imaging spectrometer is proposed based off the plenoptic configuration.

  4. A structural design decomposition method utilizing substructuring

    NASA Technical Reports Server (NTRS)

    Scotti, Stephen J.

    1994-01-01

    A new method of design decomposition for structural analysis and optimization is described. For this method, the structure is divided into substructures where each substructure has its structural response described by a structural-response subproblem, and its structural sizing determined from a structural-sizing subproblem. The structural responses of substructures that have rigid body modes when separated from the remainder of the structure are further decomposed into displacements that have no rigid body components, and a set of rigid body modes. The structural-response subproblems are linked together through forces determined within a structural-sizing coordination subproblem which also determines the magnitude of any rigid body displacements. Structural-sizing subproblems having constraints local to the substructures are linked together through penalty terms that are determined by a structural-sizing coordination subproblem. All the substructure structural-response subproblems are totally decoupled from each other, as are all the substructure structural-sizing subproblems, thus there is significant potential for use of parallel solution methods for these subproblems.

  5. Neural method of spatiotemporal filter design

    NASA Astrophysics Data System (ADS)

    Szostakowski, Jaroslaw

    1997-10-01

    There is a lot of applications in medical imaging, computer vision, and the communications, where the video processing is critical. Although many techniques have been successfully developed for the filtering of the still-images, significantly fewer techniques have been proposed for the filtering of noisy image sequences. In this paper the novel approach to spatio- temporal filtering design is proposed. The multilayer perceptrons and functional-link nets are used for the 3D filtering. The spatio-temporal patterns are creating from real motion video images. The neural networks learn these patterns. The perceptrons with different number of layers and neurons in each layer are tested. Also, the different input functions in functional- link net are searched. The practical examples of the filtering are shown and compared with traditional (non-neural) spatio-temporal methods. The results are very interesting and the neural spatio-temporal filters seems to be very efficient tool for video noise reduction.

  6. Method for designing gas tag compositions

    DOEpatents

    Gross, K.C.

    1995-04-11

    For use in the manufacture of gas tags such as employed in a nuclear reactor gas tagging failure detection system, a method for designing gas tagging compositions utilizes an analytical approach wherein the final composition of a first canister of tag gas as measured by a mass spectrometer is designated as node No. 1. Lattice locations of tag nodes in multi-dimensional space are then used in calculating the compositions of a node No. 2 and each subsequent node so as to maximize the distance of each node from any combination of tag components which might be indistinguishable from another tag composition in a reactor fuel assembly. Alternatively, the measured compositions of tag gas numbers 1 and 2 may be used to fix the locations of nodes 1 and 2, with the locations of nodes 3-N then calculated for optimum tag gas composition. A single sphere defining the lattice locations of the tag nodes may be used to define approximately 20 tag nodes, while concentric spheres can extend the number of tag nodes to several hundred. 5 figures.

  7. Method for designing gas tag compositions

    DOEpatents

    Gross, Kenny C.

    1995-01-01

    For use in the manufacture of gas tags such as employed in a nuclear reactor gas tagging failure detection system, a method for designing gas tagging compositions utilizes an analytical approach wherein the final composition of a first canister of tag gas as measured by a mass spectrometer is designated as node #1. Lattice locations of tag nodes in multi-dimensional space are then used in calculating the compositions of a node #2 and each subsequent node so as to maximize the distance of each node from any combination of tag components which might be indistinguishable from another tag composition in a reactor fuel assembly. Alternatively, the measured compositions of tag gas numbers 1 and 2 may be used to fix the locations of nodes 1 and 2, with the locations of nodes 3-N then calculated for optimum tag gas composition. A single sphere defining the lattice locations of the tag nodes may be used to define approximately 20 tag nodes, while concentric spheres can extend the number of tag nodes to several hundred.

  8. Research and Design of Rootkit Detection Method

    NASA Astrophysics Data System (ADS)

    Liu, Leian; Yin, Zuanxing; Shen, Yuli; Lin, Haitao; Wang, Hongjiang

    Rootkit is one of the most important issues of network communication systems, which is related to the security and privacy of Internet users. Because of the existence of the back door of the operating system, a hacker can use rootkit to attack and invade other people's computers and thus he can capture passwords and message traffic to and from these computers easily. With the development of the rootkit technology, its applications are more and more extensive and it becomes increasingly difficult to detect it. In addition, for various reasons such as trade secrets, being difficult to be developed, and so on, the rootkit detection technology information and effective tools are still relatively scarce. In this paper, based on the in-depth analysis of the rootkit detection technology, a new kind of the rootkit detection structure is designed and a new method (software), X-Anti, is proposed. Test results show that software designed based on structure proposed is much more efficient than any other rootkit detection software.

  9. Geometric methods for optimal sensor design.

    PubMed

    Belabbas, M-A

    2016-01-01

    The Kalman-Bucy filter is the optimal estimator of the state of a linear dynamical system from sensor measurements. Because its performance is limited by the sensors to which it is paired, it is natural to seek optimal sensors. The resulting optimization problem is however non-convex. Therefore, many ad hoc methods have been used over the years to design sensors in fields ranging from engineering to biology to economics. We show in this paper how to obtain optimal sensors for the Kalman filter. Precisely, we provide a structural equation that characterizes optimal sensors. We furthermore provide a gradient algorithm and prove its convergence to the optimal sensor. This optimal sensor yields the lowest possible estimation error for measurements with a fixed signal-to-noise ratio. The results of the paper are proved by reducing the optimal sensor problem to an optimization problem on a Grassmannian manifold and proving that the function to be minimized is a Morse function with a unique minimum. The results presented here also apply to the dual problem of optimal actuator design.

  10. Geometric methods for optimal sensor design

    PubMed Central

    Belabbas, M.-A.

    2016-01-01

    The Kalman–Bucy filter is the optimal estimator of the state of a linear dynamical system from sensor measurements. Because its performance is limited by the sensors to which it is paired, it is natural to seek optimal sensors. The resulting optimization problem is however non-convex. Therefore, many ad hoc methods have been used over the years to design sensors in fields ranging from engineering to biology to economics. We show in this paper how to obtain optimal sensors for the Kalman filter. Precisely, we provide a structural equation that characterizes optimal sensors. We furthermore provide a gradient algorithm and prove its convergence to the optimal sensor. This optimal sensor yields the lowest possible estimation error for measurements with a fixed signal-to-noise ratio. The results of the paper are proved by reducing the optimal sensor problem to an optimization problem on a Grassmannian manifold and proving that the function to be minimized is a Morse function with a unique minimum. The results presented here also apply to the dual problem of optimal actuator design. PMID:26997885

  11. Adjoint methods for aerodynamic wing design

    NASA Technical Reports Server (NTRS)

    Grossman, Bernard

    1993-01-01

    A model inverse design problem is used to investigate the effect of flow discontinuities on the optimization process. The optimization involves finding the cross-sectional area distribution of a duct that produces velocities that closely match a targeted velocity distribution. Quasi-one-dimensional flow theory is used, and the target is chosen to have a shock wave in its distribution. The objective function which quantifies the difference between the targeted and calculated velocity distributions may become non-smooth due to the interaction between the shock and the discretization of the flowfield. This paper offers two techniques to resolve the resulting problems for the optimization algorithms. The first, shock-fitting, involves careful integration of the objective function through the shock wave. The second, coordinate straining with shock penalty, uses a coordinate transformation to align the calculated shock with the target and then adds a penalty proportional to the square of the distance between the shocks. The techniques are tested using several popular sensitivity and optimization methods, including finite-differences, and direct and adjoint discrete sensitivity methods. Two optimization strategies, Gauss-Newton and sequential quadratic programming (SQP), are used to drive the objective function to a minimum.

  12. Educating Instructional Designers: Different Methods for Different Outcomes.

    ERIC Educational Resources Information Center

    Rowland, Gordon; And Others

    1994-01-01

    Suggests new methods of teaching instructional design based on literature reviews of other design fields including engineering, architecture, interior design, media design, and medicine. Methods discussed include public presentations, visiting experts, competitions, artifacts, case studies, design studios, and internships and apprenticeships.…

  13. Game Methodology for Design Methods and Tools Selection

    ERIC Educational Resources Information Center

    Ahmad, Rafiq; Lahonde, Nathalie; Omhover, Jean-françois

    2014-01-01

    Design process optimisation and intelligence are the key words of today's scientific community. A proliferation of methods has made design a convoluted area. Designers are usually afraid of selecting one method/tool over another and even expert designers may not necessarily know which method is the best to use in which circumstances. This…

  14. Barriers in using cardiometabolic risk information among consumers with low health literacy.

    PubMed

    Damman, Olga C; Bogaerts, Nina M M; van Dongen, Diana; Timmermans, Danielle R M

    2016-02-01

    To identify the barriers from the perspective of consumers with low health literacy in using risk information as provided in cardiometabolic risk assessments. A qualitative thematic approach using cognitive interviews was employed. We performed interviews with 23 people with low health literacy/health numeracy, who were recruited through (1) several organisations and snowball sampling and (2) an online access panel. Participants completed the risk test of the Dutch national cardiometabolic risk assessment and viewed the personalized information about their risk. They were asked to answer probing questions about different parts of the information. The qualitative data were analysed by identifying main themes related to barriers in using the information, using a descriptive thematic approach. The four main themes identified were as follows: (1) People did not fully accept the risk message, partly because numerical information had ambiguous meaning; (2) people lacked an adequate framework for understanding their risk; (3) the purpose and setting of the risk assessment was unclear; and (4) current information tells nothing new: A need for more specific risk information. The main barriers were that the current presentation seemed to provoke undervaluation of the risk number and that texts throughout the test, for example about cardiometabolic diseases, did not match people's existing knowledge, failing to provide an adequate framework for understanding cardiometabolic risk. Our findings have implications for the design of disease risk information, for example that alternative forms of communication should be explored that provide more intuitive meaning of the risk in terms of good versus bad. What is already known on this subject? Online disease risk assessments have become widely available internationally. People with low SES and health literacy tend to participate less in health screening. Risk information is difficult to understand, yet little research has been

  15. Translating Vision into Design: A Method for Conceptual Design Development

    NASA Technical Reports Server (NTRS)

    Carpenter, Joyce E.

    2003-01-01

    One of the most challenging tasks for engineers is the definition of design solutions that will satisfy high-level strategic visions and objectives. Even more challenging is the need to demonstrate how a particular design solution supports the high-level vision. This paper describes a process and set of system engineering tools that have been used at the Johnson Space Center to analyze and decompose high-level objectives for future human missions into design requirements that can be used to develop alternative concepts for vehicles, habitats, and other systems. Analysis and design studies of alternative concepts and approaches are used to develop recommendations for strategic investments in research and technology that support the NASA Integrated Space Plan. In addition to a description of system engineering tools, this paper includes a discussion of collaborative design practices for human exploration mission architecture studies used at the Johnson Space Center.

  16. Risky business: risk information and the moderating effect of message frame and past behaviour on women's perceptions of the Human Papillomavirus vaccine.

    PubMed

    Gainforth, Heather L; Latimer, Amy E

    2012-09-01

    The effect of response cost information, message framing and past behaviour on women's coping appraisal and motivation to be vaccinated against the Human Papillomavirus (HPV) were investigated using a 2 Frame × 2 Response Cost × 2 Pap Status design. Women (N = 286) read one of four messages about the vaccine. Women who received high-risk information perceived the vaccine as having higher response cost and were less motivated to be vaccinated compared to women who received low-risk information. The deleterious effects of risk information on specific aspects of women's coping appraisal may be mitigated by appropriately framed messages.

  17. Using Software Design Methods in CALL

    ERIC Educational Resources Information Center

    Ward, Monica

    2006-01-01

    The phrase "software design" is not one that arouses the interest of many CALL practitioners, particularly those from a humanities background. However, software design essentials are simply logical ways of going about designing a system. The fundamentals include modularity, anticipation of change, generality and an incremental approach. While CALL…

  18. Global optimization methods for engineering design

    NASA Technical Reports Server (NTRS)

    Arora, Jasbir S.

    1990-01-01

    The problem is to find a global minimum for the Problem P. Necessary and sufficient conditions are available for local optimality. However, global solution can be assured only under the assumption of convexity of the problem. If the constraint set S is compact and the cost function is continuous on it, existence of a global minimum is guaranteed. However, in view of the fact that no global optimality conditions are available, a global solution can be found only by an exhaustive search to satisfy Inequality. The exhaustive search can be organized in such a way that the entire design space need not be searched for the solution. This way the computational burden is reduced somewhat. It is concluded that zooming algorithm for global optimizations appears to be a good alternative to stochastic methods. More testing is needed; a general, robust, and efficient local minimizer is required. IDESIGN was used in all numerical calculations which is based on a sequential quadratic programming algorithm, and since feasible set keeps on shrinking, a good algorithm to find an initial feasible point is required. Such algorithms need to be developed and evaluated.

  19. An Efficient Inverse Aerodynamic Design Method For Subsonic Flows

    NASA Technical Reports Server (NTRS)

    Milholen, William E., II

    2000-01-01

    Computational Fluid Dynamics based design methods are maturing to the point that they are beginning to be used in the aircraft design process. Many design methods however have demonstrated deficiencies in the leading edge region of airfoil sections. The objective of the present research is to develop an efficient inverse design method which is valid in the leading edge region. The new design method is a streamline curvature method, and a new technique is presented for modeling the variation of the streamline curvature normal to the surface. The new design method allows the surface coordinates to move normal to the surface, and has been incorporated into the Constrained Direct Iterative Surface Curvature (CDISC) design method. The accuracy and efficiency of the design method is demonstrated using both two-dimensional and three-dimensional design cases.

  20. Design optimization method for Francis turbine

    NASA Astrophysics Data System (ADS)

    Kawajiri, H.; Enomoto, Y.; Kurosawa, S.

    2014-03-01

    This paper presents a design optimization system coupled CFD. Optimization algorithm of the system employs particle swarm optimization (PSO). Blade shape design is carried out in one kind of NURBS curve defined by a series of control points. The system was applied for designing the stationary vanes and the runner of higher specific speed francis turbine. As the first step, single objective optimization was performed on stay vane profile, and second step was multi-objective optimization for runner in wide operating range. As a result, it was confirmed that the design system is useful for developing of hydro turbine.

  1. Materials Reliability Program: Risk-Informed Revision of ASME Section XI Appendix G - Proof of Concept (MRP-143)

    SciTech Connect

    B. Bishop; et al

    2005-03-30

    This study indicates that risk-informed methods can be used to significantly relax the current ASME and NRC Appendix G requirements while still maintaining satisfactory levels of reactor vessel structural integrity. This relaxation in Appendix G requirements directly translates into significant improvements in operational flexibility.

  2. Alternative methods for the design of jet engine control systems

    NASA Technical Reports Server (NTRS)

    Sain, M. K.; Leake, R. J.; Basso, R.; Gejji, R.; Maloney, A.; Seshadri, V.

    1976-01-01

    Various alternatives to linear quadratic design methods for jet engine control systems are discussed. The main alternatives are classified into two broad categories: nonlinear global mathematical programming methods and linear local multivariable frequency domain methods. Specific studies within these categories include model reduction, the eigenvalue locus method, the inverse Nyquist method, polynomial design, dynamic programming, and conjugate gradient approaches.

  3. Alternative methods for the design of jet engine control systems

    NASA Technical Reports Server (NTRS)

    Sain, M. K.; Leake, R. J.; Basso, R.; Gejji, R.; Maloney, A.; Seshadri, V.

    1976-01-01

    Various alternatives to linear quadratic design methods for jet engine control systems are discussed. The main alternatives are classified into two broad categories: nonlinear global mathematical programming methods and linear local multivariable frequency domain methods. Specific studies within these categories include model reduction, the eigenvalue locus method, the inverse Nyquist method, polynomial design, dynamic programming, and conjugate gradient approaches.

  4. Demystifying Mixed Methods Research Design: A Review of the Literature

    ERIC Educational Resources Information Center

    Caruth, Gail D.

    2013-01-01

    Mixed methods research evolved in response to the observed limitations of both quantitative and qualitative designs and is a more complex method. The purpose of this paper was to examine mixed methods research in an attempt to demystify the design thereby allowing those less familiar with its design an opportunity to utilize it in future research.…

  5. Computational Methods Applied to Rational Drug Design.

    PubMed

    Ramírez, David

    2016-01-01

    Due to the synergic relationship between medical chemistry, bioinformatics and molecular simulation, the development of new accurate computational tools for small molecules drug design has been rising over the last years. The main result is the increased number of publications where computational techniques such as molecular docking, de novo design as well as virtual screening have been used to estimate the binding mode, site and energy of novel small molecules. In this work I review some tools, which enable the study of biological systems at the atomistic level, providing relevant information and thereby, enhancing the process of rational drug design.

  6. Computational Methods Applied to Rational Drug Design

    PubMed Central

    Ramírez, David

    2016-01-01

    Due to the synergic relationship between medical chemistry, bioinformatics and molecular simulation, the development of new accurate computational tools for small molecules drug design has been rising over the last years. The main result is the increased number of publications where computational techniques such as molecular docking, de novo design as well as virtual screening have been used to estimate the binding mode, site and energy of novel small molecules. In this work I review some tools, which enable the study of biological systems at the atomistic level, providing relevant information and thereby, enhancing the process of rational drug design. PMID:27708723

  7. The Work Design Method for Human Friendly

    NASA Astrophysics Data System (ADS)

    Harada, Narumi; Sasaki, Masatoshi; Ichikawa, Masami

    In order to realize “the product life cycle with respect for human nature". we ought to make work design so that work environment should be configured to be sound in mind and body, with due consideration of not only physical but also mental factors from the viewpoint of workers. The former includes too heavy work, unreasonable working posture, local fatigue of the body, the safety, and working comfort, and the latter includes work motivation, work worthiness, stress, etc. For the purpose of evaluating the degree of working comfort and safety at human-oriented production lines, we acknowledged, for the work design, the effectiveness of the work designing technique with working time variation duly considered. And, we formulated a model for a mental factor experienced by workers from the degree of working delays. This study covers a work design technique we developed with the effect of the factor as the value of evaluation.

  8. A Method of Integrated Description of Design Information for Reusability

    NASA Astrophysics Data System (ADS)

    Tsumaya, Akira; Nagae, Masao; Wakamatsu, Hidefumi; Shirase, Keiichi; Arai, Eiji

    Much of product design is executed concurrently these days. For such concurrent design, the method which can share and ueuse varioud kind of design information among designers is needed. However, complete understanding of the design information among designers have been a difficult issue. In this paper, design process model with use of designers’ intention is proposed. A method to combine the design process information and the design object information is also proposed. We introduce how to describe designers’ intention by providing some databases. Keyword Database consists of ontological data related to design object/activities. Designers select suitable keyword(s) from Keyword Database and explain the reason/ideas for their design activities by the description with use of keyword(s). We also developed the integration design information management system architecture by using a method of integrated description with designers’ intension. This system realizes connections between the information related to design process and that related to design object through designers’ intention. Designers can communicate with each other to understand how others make decision in design through that. Designers also can re-use both design process information data and design object information data through detabase management sub-system.

  9. Supersonic biplane design via adjoint method

    NASA Astrophysics Data System (ADS)

    Hu, Rui

    In developing the next generation supersonic transport airplane, two major challenges must be resolved. The fuel efficiency must be significantly improved, and the sonic boom propagating to the ground must be dramatically reduced. Both of these objectives can be achieved by reducing the shockwaves formed in supersonic flight. The Busemann biplane is famous for using favorable shockwave interaction to achieve nearly shock-free supersonic flight at its design Mach number. Its performance at off-design Mach numbers, however, can be very poor. This dissertation studies the performance of supersonic biplane airfoils at design and off-design conditions. The choked flow and flow-hysteresis phenomena of these biplanes are studied. These effects are due to finite thickness of the airfoils and non-uniqueness of the solution to the Euler equations, creating over an order of magnitude more wave drag than that predicted by supersonic thin airfoil theory. As a result, the off-design performance is the major barrier to the practical use of supersonic biplanes. The main contribution of this work is to drastically improve the off-design performance of supersonic biplanes by using an adjoint based aerodynamic optimization technique. The Busemann biplane is used as the baseline design, and its shape is altered to achieve optimal wave drags in series of Mach numbers ranging from 1.1 to 1.7, during both acceleration and deceleration conditions. The optimized biplane airfoils dramatically reduces the effects of the choked flow and flow-hysteresis phenomena, while maintaining a certain degree of favorable shockwave interaction effects at the design Mach number. Compared to a diamond shaped single airfoil of the same total thickness, the wave drag of our optimized biplane is lower at almost all Mach numbers, and is significantly lower at the design Mach number. In addition, by performing a Navier-Stokes solution for the optimized airfoil, it is verified that the optimized biplane improves

  10. JASMINE design and method of data reduction

    NASA Astrophysics Data System (ADS)

    Yamada, Yoshiyuki; Gouda, Naoteru; Yano, Taihei; Kobayashi, Yukiyasu; Niwa, Yoshito

    2008-07-01

    Japan Astrometry Satellite Mission for Infrared Exploration (JASMINE) aims to construct a map of the Galactic bulge with 10 μ arc sec accuracy. We use z-band CCD for avoiding dust absorption, and observe about 10 × 20 degrees area around the Galactic bulge region. Because the stellar density is very high, each FOVs can be combined with high accuracy. With 5 years observation, we will construct 10 μ arc sec accurate map. In this poster, I will show the observation strategy, design of JASMINE hardware, reduction scheme, and error budget. We also construct simulation software named JASMINE Simulator. We also show the simulation results and design of software.

  11. Designing a mixed methods study in pediatric oncology nursing research.

    PubMed

    Wilkins, Krista; Woodgate, Roberta

    2008-01-01

    Despite the appeal of discovering the different strengths of various research methods, mixed methods research remains elusive in pediatric oncology nursing research. If pediatric oncology nurses are to succeed in mixing quantitative and qualitative methods, they need practical guidelines for managing the complex data and analyses of mixed methods research. This article discusses mixed methods terminology, designs, and key design features. Specific areas addressed include the myths about mixed methods research, types of mixed method research designs, steps involved in developing a mixed method research study, and the benefits and challenges of using mixed methods designs in pediatric oncology research. Examples of recent research studies that have combined quantitative and qualitative research methods are provided. The term mixed methods research is used throughout this article to reflect the use of both quantitative and qualitative methods within one study rather than the use of these methods in separate studies concerning the same research problem.

  12. Which Type of Risk Information to Use for Whom? Moderating Role of Outcome-Relevant Involvement in the Effects of Statistical and Exemplified Risk Information on Risk Perceptions.

    PubMed

    So, Jiyeon; Jeong, Se-Hoon; Hwang, Yoori

    2017-04-01

    The extant empirical research examining the effectiveness of statistical and exemplar-based health information is largely inconsistent. Under the premise that the inconsistency may be due to an unacknowledged moderator (O'Keefe, 2002), this study examined a moderating role of outcome-relevant involvement (Johnson & Eagly, 1989) in the effects of statistical and exemplified risk information on risk perception. Consistent with predictions based on elaboration likelihood model (Petty & Cacioppo, 1984), findings from an experiment (N = 237) concerning alcohol consumption risks showed that statistical risk information predicted risk perceptions of individuals with high, rather than low, involvement, while exemplified risk information predicted risk perceptions of those with low, rather than high, involvement. Moreover, statistical risk information contributed to negative attitude toward drinking via increased risk perception only for highly involved individuals, while exemplified risk information influenced the attitude through the same mechanism only for individuals with low involvement. Theoretical and practical implications for health risk communication are discussed.

  13. A method for nonlinear optimization with discrete design variables

    NASA Technical Reports Server (NTRS)

    Olsen, Gregory R.; Vanderplaats, Garret N.

    1987-01-01

    A numerical method is presented for the solution of nonlinear discrete optimization problems. The applicability of discrete optimization to engineering design is discussed, and several standard structural optimization problems are solved using discrete design variables. The method uses approximation techniques to create subproblems suitable for linear mixed-integer programming methods. The method employs existing software for continuous optimization and integer programming.

  14. A method for nonlinear optimization with discrete design variables

    NASA Technical Reports Server (NTRS)

    Olsen, Gregory R.; Vanderplaats, Garret N.

    1987-01-01

    A numerical method is presented for the solution of nonlinear discrete optimization problems. The applicability of discrete optimization to engineering design is discussed, and several standard structural optimization problems are solved using discrete design variables. The method uses approximation techniques to create subproblems suitable for linear mixed-integer programming methods. The method employs existing software for continuous optimization and integer programming.

  15. Lithography aware overlay metrology target design method

    NASA Astrophysics Data System (ADS)

    Lee, Myungjun; Smith, Mark D.; Lee, Joonseuk; Jung, Mirim; Lee, Honggoo; Kim, Youngsik; Han, Sangjun; Adel, Michael E.; Lee, Kangsan; Lee, Dohwa; Choi, Dongsub; Liu, Zephyr; Itzkovich, Tal; Levinski, Vladimir; Levy, Ady

    2016-03-01

    We present a metrology target design (MTD) framework based on co-optimizing lithography and metrology performance. The overlay metrology performance is strongly related to the target design and optimizing the target under different process variations in a high NA optical lithography tool and measurement conditions in a metrology tool becomes critical for sub-20nm nodes. The lithography performance can be quantified by device matching and printability metrics, while accuracy and precision metrics are used to quantify the metrology performance. Based on using these metrics, we demonstrate how the optimized target can improve target printability while maintaining the good metrology performance for rotated dipole illumination used for printing a sub-100nm diagonal feature in a memory active layer. The remaining challenges and the existing tradeoff between metrology and lithography performance are explored with the metrology target designer's perspective. The proposed target design framework is completely general and can be used to optimize targets for different lithography conditions. The results from our analysis are both physically sensible and in good agreement with experimental results.

  16. Participatory design methods in telemedicine research.

    PubMed

    Clemensen, Jane; Rothmann, Mette J; Smith, Anthony C; Caffery, Liam J; Danbjorg, Dorthe B

    2016-01-01

    Healthcare systems require a paradigm shift in the way healthcare services are delivered to counteract demographic changes in patient populations, expanding technological developments and the increasing complexity of healthcare. Participatory design (PD) is a methodology that promotes the participation of users in the design process of potential telehealth applications. A PD project can be divided into four phases including: the identification and analysis of participant needs; the generation of ideas and development of prototypes; testing and further development of prototypes; and evaluation. PD is an iterative process where each phase is planned by reflecting on the results from the previous phase with respect to the participants' contribution. Key activities of a PD project include: fieldwork; literature reviewing; and development and testing. All activities must be applied with a participatory mindset that will ensure genuine participation throughout the project. Challenges associated with the use of PD include: the time required to properly engage with participants; language and culture barriers amongst participants; the selection of participants to ensure good representation of the user group; and empowerment. PD is an important process, which is complemented by other evaluation strategies that assess organisational requirements, clinical safety, and clinical and cost effectiveness. PD is a methodology which encourages genuine involvement, where participants have an opportunity to identify practical problems and to design and test technology. The process engages participants in storytelling, future planning and design. PD is a multifaceted assessment tool that helps explore more accurately clinical requirements and patient perspectives in telehealth.

  17. The application of mixed methods designs to trauma research.

    PubMed

    Creswell, John W; Zhang, Wanqing

    2009-12-01

    Despite the use of quantitative and qualitative data in trauma research and therapy, mixed methods studies in this field have not been analyzed to help researchers designing investigations. This discussion begins by reviewing four core characteristics of mixed methods research in the social and human sciences. Combining these characteristics, the authors focus on four select mixed methods designs that are applicable in trauma research. These designs are defined and their essential elements noted. Applying these designs to trauma research, a search was conducted to locate mixed methods trauma studies. From this search, one sample study was selected, and its characteristics of mixed methods procedures noted. Finally, drawing on other mixed methods designs available, several follow-up mixed methods studies were described for this sample study, enabling trauma researchers to view design options for applying mixed methods research in trauma investigations.

  18. Methods for library-scale computational protein design.

    PubMed

    Johnson, Lucas B; Huber, Thaddaus R; Snow, Christopher D

    2014-01-01

    Faced with a protein engineering challenge, a contemporary researcher can choose from myriad design strategies. Library-scale computational protein design (LCPD) is a hybrid method suitable for the engineering of improved protein variants with diverse sequences. This chapter discusses the background and merits of several practical LCPD techniques. First, LCPD methods suitable for delocalized protein design are presented in the context of example design calculations for cellobiohydrolase II. Second, localized design methods are discussed in the context of an example design calculation intended to shift the substrate specificity of a ketol-acid reductoisomerase Rossmann domain from NADPH to NADH.

  19. Probabilistic Methods for Structural Design and Reliability

    NASA Technical Reports Server (NTRS)

    Chamis, Christos C.; Whitlow, Woodrow, Jr. (Technical Monitor)

    2002-01-01

    This report describes a formal method to quantify structural damage tolerance and reliability in the presence of a multitude of uncertainties in turbine engine components. The method is based at the material behavior level where primitive variables with their respective scatter ranges are used to describe behavior. Computational simulation is then used to propagate the uncertainties to the structural scale where damage tolerance and reliability are usually specified. Several sample cases are described to illustrate the effectiveness, versatility, and maturity of the method. Typical results from this method demonstrate, that it is mature and that it can be used to probabilistically evaluate turbine engine structural components. It may be inferred from the results that the method is suitable for probabilistically predicting the remaining life in aging or in deteriorating structures, for making strategic projections and plans, and for achieving better, cheaper, faster products that give competitive advantages in world markets.

  20. A comparison of digital flight control design methods

    NASA Technical Reports Server (NTRS)

    Powell, J. D.; Parsons, E.; Tashker, M. G.

    1976-01-01

    Many variations in design methods for aircraft digital flight control have been proposed in the literature. In general, the methods fall into two categories: those where the design is done in the continuous domain (or s-plane), and those where the design is done in the discrete domain (or z-plane). This paper evaluates several variations of each category and compares them for various flight control modes of the Langley TCV Boeing 737 aircraft. Design method fidelity is evaluated by examining closed loop root movement and the frequency response of the discretely controlled continuous aircraft. It was found that all methods provided acceptable performance for sample rates greater than 10 cps except the 'uncompensated s-plane design' method which was acceptable above 20 cps. A design procedure based on optimal control methods was proposed that provided the best fidelity at very slow sample rates and required no design iterations for changing sample rates.

  1. Improved hybrid SMS-DSF method of nonimaging optical design

    NASA Astrophysics Data System (ADS)

    Bortz, John; Shatz, Narkis

    2011-10-01

    The hybrid SMS-DSF method of nonimaging optical design combines the discrete simultaneous multiple surface (SMS) method with the dual-surface functional (DSF) method to obtain improved optical performance relative to the discrete SMS method alone. In this contribution we present a new extension of the hybrid SMS-DSF method that uses differential ray tracing to produce designs having significantly improved performance relative to the original hybrid SMS-DSF method.

  2. Light Water Reactor Sustainability Program Risk Informed Safety Margin Characterization (RISMC) Advanced Test Reactor Demonstration Case Study

    SciTech Connect

    Curtis Smith; David Schwieder; Cherie Phelan; Anh Bui; Paul Bayless

    2012-08-01

    Safety is central to the design, licensing, operation, and economics of Nuclear Power Plants (NPPs). Consequently, the ability to better characterize and quantify safety margin holds the key to improved decision making about LWR design, operation, and plant life extension. A systematic approach to characterization of safety margins and the subsequent margins management options represents a vital input to the licensee and regulatory analysis and decision making that will be involved. The purpose of the RISMC Pathway R&D is to support plant decisions for risk-informed margins management with the aim to improve economics, reliability, and sustain safety of current NPPs. Goals of the RISMC Pathway are twofold: (1) Develop and demonstrate a risk-assessment method coupled to safety margin quantification that can be used by NPP decision makers as part of their margin recovery strategies. (2) Create an advanced “RISMC toolkit” that enables more accurate representation of NPP safety margin. This report describes the RISMC methodology demonstration where the Advanced Test Reactor (ATR) was used as a test-bed for purposes of determining safety margins. As part of the demonstration, we describe how both the thermal-hydraulics and probabilistic safety calculations are integrated and used to quantify margin management strategies.

  3. Computational Methods for Design, Control and Optimization

    DTIC Science & Technology

    2007-10-01

    34scenario" that applies to channel flows ( Poiseuille flows , Couette flow ) and pipe flows . Over the past 75 years many complex "transition theories" have... Simulation of Turbulent Flows , Springer Verlag, 2005. Additional Publications Supported by this Grant 1. J. Borggaard and T. Iliescu, Approximate Deconvolution...rigorous analysis of design algorithms that combine numerical simulation codes, approximate sensitivity calculations and optimization codes. The fundamental

  4. Soft computing methods in design of superalloys

    NASA Technical Reports Server (NTRS)

    Cios, K. J.; Berke, L.; Vary, A.; Sharma, S.

    1995-01-01

    Soft computing techniques of neural networks and genetic algorithms are used in the design of superalloys. The cyclic oxidation attack parameter K(sub a), generated from tests at NASA Lewis Research Center, is modeled as a function of the superalloy chemistry and test temperature using a neural network. This model is then used in conjunction with a genetic algorithm to obtain an optimized superalloy composition resulting in low K(sub a) values.

  5. Soft Computing Methods in Design of Superalloys

    NASA Technical Reports Server (NTRS)

    Cios, K. J.; Berke, L.; Vary, A.; Sharma, S.

    1996-01-01

    Soft computing techniques of neural networks and genetic algorithms are used in the design of superalloys. The cyclic oxidation attack parameter K(sub a), generated from tests at NASA Lewis Research Center, is modelled as a function of the superalloy chemistry and test temperature using a neural network. This model is then used in conjunction with a genetic algorithm to obtain an optimized superalloy composition resulting in low K(sub a) values.

  6. A comparison of methods currently used in inclusive design.

    PubMed

    Goodman-Deane, Joy; Ward, James; Hosking, Ian; Clarkson, P John

    2014-07-01

    Inclusive design has unique challenges because it aims to improve usability for a wide range of users. This typically includes people with lower levels of ability, as well as mainstream users. This paper examines the effectiveness of two methods that are used in inclusive design: user trials and exclusion calculations (an inclusive design inspection method). A study examined three autoinjectors using both methods (n=30 for the user trials). The usability issues identified by each method are compared and the effectiveness of the methods is discussed. The study found that each method identified different kinds of issues, all of which are important for inclusive design. We therefore conclude that a combination of methods should be used in inclusive design rather than relying on a single method. Recommendations are also given for how the individual methods can be used more effectively in this context.

  7. Waterflooding injectate design systems and methods

    DOEpatents

    Brady, Patrick V.; Krumhansl, James L.

    2016-12-13

    A method of recovering a liquid hydrocarbon using an injectate includes recovering the liquid hydrocarbon through primary extraction. Physico-chemical data representative of electrostatic interactions between the liquid hydrocarbon and the reservoir rock are measured. At least one additive of the injectate is selected based on the physico-chemical data. The method includes recovering the liquid hydrocarbon from the reservoir rock through secondary extraction using the injectate.

  8. An overview of very high level software design methods

    NASA Technical Reports Server (NTRS)

    Asdjodi, Maryam; Hooper, James W.

    1988-01-01

    Very High Level design methods emphasize automatic transfer of requirements to formal design specifications, and/or may concentrate on automatic transformation of formal design specifications that include some semantic information of the system into machine executable form. Very high level design methods range from general domain independent methods to approaches implementable for specific applications or domains. Applying AI techniques, abstract programming methods, domain heuristics, software engineering tools, library-based programming and other methods different approaches for higher level software design are being developed. Though one finds that a given approach does not always fall exactly in any specific class, this paper provides a classification for very high level design methods including examples for each class. These methods are analyzed and compared based on their basic approaches, strengths and feasibility for future expansion toward automatic development of software systems.

  9. Comparison of four nonstationary hydrologic design methods for changing environment

    NASA Astrophysics Data System (ADS)

    Yan, Lei; Xiong, Lihua; Guo, Shenglian; Xu, Chong-Yu; Xia, Jun; Du, Tao

    2017-08-01

    The hydrologic design of nonstationary flood extremes is an emerging field that is essential for water resources management and hydrologic engineering design to cope with changing environment. This paper aims to investigate and compare the capability of four nonstationary hydrologic design strategies, including the expected number of exceedances (ENE), design life level (DLL), equivalent reliability (ER), and average design life level (ADLL), with the last three methods taking into consideration the design life of the project. The confidence intervals of the calculated design floods were also estimated using the nonstationary bootstrap approach. A comparison of these four methods was performed using the annual maximum flood series (AMFS) of the Weihe River basin, Jinghe River basin, and Assunpink Creek basin. The results indicated that ENE, ER and ADLL yielded the same or very similar design values and confidence intervals for both increasing and decreasing trends of AMFS considered. DLL also yields similar design values if the relationship between DLL and ER/ADLL return periods is considered. Both ER and ADLL are recommended for practical use as they have associated design floods with the design life period of projects and yield reasonable design quantiles and confidence intervals. Furthermore, by assuming that the design results using either a stationary or nonstationary hydrologic design strategy should have the same reliability, the ER method enables us to solve the nonstationary hydrologic design problems by adopting the stationary design reliability, thus bridging the gap between stationary and nonstationary design criteria.

  10. Using web-based familial risk information for diabetes prevention: a randomized controlled trial

    PubMed Central

    2013-01-01

    Background It has been suggested that family history information may be effective in motivating people to adopt health promoting behaviour. The aim was to determine if diabetic familial risk information by using a web-based tool leads to improved self-reported risk-reducing behaviour among individuals with a diabetic family history, without causing false reassurance among those without a family history. Methods An online sample of 1,174 healthy adults aged 35–65 years with a BMI ≥ 25 was randomized into two groups receiving an online diabetes risk assessment. Both arms received general tailored diabetes prevention information, whilst the intervention arm also received familial risk information after completing a detailed family history questionnaire. Separate analysis was performed for four groups (family history group: 286 control versus 288 intervention group; no family history: 269 control versus 266 intervention group). Primary outcomes were self-reported behavioural outcomes: fat intake, physical activity, and attitudes towards diabetes testing. Secondary outcomes were illness and risk perceptions. Results For individuals at familial risk there was no overall intervention effect on risk-reducing behaviour after three months, except for a decrease in self-reported saturated fat intake among low-educated individuals (Beta (b) -1.01, 95% CI −2.01 to 0.00). Familial risk information resulted in a decrease of diabetes risk worries (b −0.21, -0.40 to −0.03). For individuals without family history no effect was found on risk-reducing behaviour and perceived risk. A detailed family history assessment resulted in a greater percentage of individuals reporting a familial risk for diabetes compared to a simple enquiry. Conclusions Web-based familial risk information reduced worry related to diabetes risk and decreased saturated fat intake of those at greatest need of preventative care. However, the intervention was not effective for the total study population on

  11. Background risk information to assist in risk management decision making

    SciTech Connect

    Hammonds, J.S.; Hoffman, F.O.; White, R.K.; Miller, D.B.

    1992-10-01

    The evaluation of the need for remedial activities at hazardous waste sites requires quantification of risks of adverse health effects to humans and the ecosystem resulting from the presence of chemical and radioactive substances at these sites. The health risks from exposure to these substances are in addition to risks encountered because of the virtually unavoidable exposure to naturally occurring chemicals and radioactive materials that are present in air, water, soil, building materials, and food products. To provide a frame of reference for interpreting risks quantified for hazardous waste sites, it is useful to identify the relative magnitude of risks of both a voluntary and involuntary nature that are ubiquitous throughout east Tennessee. In addition to discussing risks from the ubiquitous presence of background carcinogens in the east Tennessee environment, this report also presents risks resulting from common, everyday activities. Such information should, not be used to discount or trivialize risks from hazardous waste contamination, but rather, to create a sensitivity to general risk issues, thus providing a context for better interpretation of risk information.

  12. Defining resilience within a risk-informed assessment framework

    SciTech Connect

    Coles, Garill A.; Unwin, Stephen D.; Holter, Gregory M.; Bass, Robert B.; Dagle, Jeffery E.

    2011-08-01

    The concept of resilience is the subject of considerable discussion in academic, business, and governmental circles. The United States Department of Homeland Security for one has emphasised the need to consider resilience in safeguarding critical infrastructure and key resources. The concept of resilience is complex, multidimensional, and defined differently by different stakeholders. The authors contend that there is a benefit in moving from discussing resilience as an abstraction to defining resilience as a measurable characteristic of a system. This paper proposes defining resilience measures using elements of a traditional risk assessment framework to help clarify the concept of resilience and as a way to provide non-traditional risk information. The authors show various, diverse dimensions of resilience can be quantitatively defined in a common risk assessment framework based on the concept of loss of service. This allows the comparison of options for improving the resilience of infrastructure and presents a means to perform cost-benefit analysis. This paper discusses definitions and key aspects of resilience, presents equations for the risk of loss of infrastructure function that incorporate four key aspects of resilience that could prevent or mitigate that loss, describes proposed resilience factor definitions based on those risk impacts, and provides an example that illustrates how resilience factors would be calculated using a hypothetical scenario.

  13. The Triton: Design concepts and methods

    NASA Technical Reports Server (NTRS)

    Meholic, Greg; Singer, Michael; Vanryn, Percy; Brown, Rhonda; Tella, Gustavo; Harvey, Bob

    1992-01-01

    During the design of the C & P Aerospace Triton, a few problems were encountered that necessitated changes in the configuration. After the initial concept phase, the aspect ratio was increased from 7 to 7.6 to produce a greater lift to drag ratio (L/D = 13) which satisfied the horsepower requirements (118 hp using the Lycoming O-235 engine). The initial concept had a wing planform area of 134 sq. ft. Detailed wing sizing analysis enlarged the planform area to 150 sq. ft., without changing its layout or location. The most significant changes, however, were made just prior to inboard profile design. The fuselage external diameter was reduced from 54 to 50 inches to reduce drag to meet the desired cruise speed of 120 knots. Also, the nose was extended 6 inches to accommodate landing gear placement. Without the extension, the nosewheel received an unacceptable percentage (25 percent) of the landing weight. The final change in the configuration was made in accordance with the stability and control analysis. In order to reduce the static margin from 20 to 13 percent, the horizontal tail area was reduced from 32.02 to 25.0 sq. ft. The Triton meets all the specifications set forth in the design criteria. If time permitted another iteration of the calculations, two significant changes would be made. The vertical stabilizer area would be reduced to decrease the aircraft lateral stability slope since the current value was too high in relation to the directional stability slope. Also, the aileron size would be decreased to reduce the roll rate below the current 106 deg/second. Doing so would allow greater flap area (increasing CL(sub max)) and thus reduce the overall wing area. C & P would also recalculate the horsepower and drag values to further validate the 120 knot cruising speed.

  14. Effects of personalized colorectal cancer risk information on laypersons’ interest in colorectal cancer screening: the importance of individual differences

    PubMed Central

    Han, Paul K.J.; Duarte, Christine W.; Daggett, Susannah; Siewers, Andrea; Killam, Bill; Smith, Kahsi A.; Freedman, Andrew N.

    2015-01-01

    Objective To evaluate how personalized quantitative colorectal cancer (CRC) risk information affects laypersons’ interest in CRC screening, and to explore factors influencing these effects. Methods An online pre-post experiment was conducted in which a convenience sample (N=578) of laypersons, aged >50, were provided quantitative personalized estimates of lifetime CRC risk, calculated by the National Cancer Institute Colorectal Cancer Risk Assessment Tool (CCRAT). Self-reported interest in CRC screening was measured immediately before and after CCRAT use; sociodemographic characteristics and prior CRC screening history were also assessed. Multivariable analyses assessed participants’ change in interest in screening, and subgroup differences in this change. Results Personalized CRC risk information had no overall effect on CRC screening interest, but significant subgroup differences were observed. Change in screening interest was greater among individuals with recent screening (p=.015), higher model-estimated cancer risk (p=.0002), and lower baseline interest (p<.0001), with individuals at highest baseline interest demonstrating negative (not neutral) change in interest. Conclusion Effects of quantitative personalized CRC risk information on laypersons’ interest in CRC screening differ among individuals depending on prior screening history, estimated cancer risk, and baseline screening interest. Practice implications Personalized cancer risk information has personalized effects—increasing and decreasing screening interest in different individuals. PMID:26227576

  15. Research and Methods for Simulation Design: State of the Art

    DTIC Science & Technology

    1990-09-01

    designers. Designers may use this review to identify methods to aid the training-device design process and individuals who manage research programs...maximum training effectiveness at a given cost. The methods should apply to the concept-formulation phase’of the training-device development process ...design process . Finally, individuals who manage research programs may use this information to set priorities for future research efforts. viii RESEARCH

  16. How to Construct a Mixed Methods Research Design.

    PubMed

    Schoonenboom, Judith; Johnson, R Burke

    2017-01-01

    This article provides researchers with knowledge of how to design a high quality mixed methods research study. To design a mixed study, researchers must understand and carefully consider each of the dimensions of mixed methods design, and always keep an eye on the issue of validity. We explain the seven major design dimensions: purpose, theoretical drive, timing (simultaneity and dependency), point of integration, typological versus interactive design approaches, planned versus emergent design, and design complexity. There also are multiple secondary dimensions that need to be considered during the design process. We explain ten secondary dimensions of design to be considered for each research study. We also provide two case studies showing how the mixed designs were constructed.

  17. Design Features of Explicit Values Clarification Methods: A Systematic Review.

    PubMed

    Witteman, Holly O; Scherer, Laura D; Gavaruzzi, Teresa; Pieterse, Arwen H; Fuhrel-Forbis, Andrea; Chipenda Dansokho, Selma; Exe, Nicole; Kahn, Valerie C; Feldman-Stewart, Deb; Col, Nananda F; Turgeon, Alexis F; Fagerlin, Angela

    2016-05-01

    Values clarification is a recommended element of patient decision aids. Many different values clarification methods exist, but there is little evidence synthesis available to guide design decisions. To describe practices in the field of explicit values clarification methods according to a taxonomy of design features. MEDLINE, all EBM Reviews, CINAHL, EMBASE, Google Scholar, manual search of reference lists, and expert contacts. Articles were included if they described 1 or more explicit values clarification methods. We extracted data about decisions addressed; use of theories, frameworks, and guidelines; and 12 design features. We identified 110 articles describing 98 explicit values clarification methods. Most of these addressed decisions in cancer or reproductive health, and half addressed a decision between just 2 options. Most used neither theory nor guidelines to structure their design. "Pros and cons" was the most common type of values clarification method. Most methods did not allow users to add their own concerns. Few methods explicitly presented tradeoffs inherent in the decision, supported an iterative process of values exploration, or showed how different options aligned with users' values. Study selection criteria and choice of elements for the taxonomy may have excluded values clarification methods or design features. Explicit values clarification methods have diverse designs but can be systematically cataloged within the structure of a taxonomy. Developers of values clarification methods should carefully consider each of the design features in this taxonomy and publish adequate descriptions of their designs. More research is needed to study the effects of different design features. © The Author(s) 2016.

  18. A survey on methods of design features identification

    NASA Astrophysics Data System (ADS)

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

    2015-11-01

    It is widely accepted that design features are one of the most attractive integration method of most fields of engineering activities such as a design modelling, process planning or production scheduling. One of the most important tasks which are realized in the integration process of design and planning functions is a design translation meant as design data mapping into data which are important from process planning needs point of view, it is manufacturing data. A design geometrical shape translation process can be realized with application one of the following strategies: (i) designing with previously prepared design features library also known as DBF method it is design by feature, (ii) interactive design features recognition IFR, (iii) automatic design features recognition AFR. In case of the DBF method design geometrical shape is created with design features. There are two basic approaches for design modelling in DBF method it is classic in which a part design is modelled from beginning to end with application design features previously stored in a design features data base and hybrid where part is partially created with standard predefined CAD system tools and the rest with suitable design features. Automatic feature recognition consist in an autonomic searching of a product model represented with a specific design representation method in order to find those model features which might be potentially recognized as design features, manufacturing features, etc. This approach needs the searching algorithm to be prepared. The searching algorithm should allow carrying on the whole recognition process without a user supervision. Currently there are lots of AFR methods. These methods need the product model to be represented with B-Rep representation most often, CSG rarely, wireframe very rarely. In the IFR method potential features are being recognized by a user. This process is most often realized by a user who points out those surfaces which seem to belong to a

  19. Design Methods and Optimization for Morphing Aircraft

    NASA Technical Reports Server (NTRS)

    Crossley, William A.

    2005-01-01

    This report provides a summary of accomplishments made during this research effort. The major accomplishments are in three areas. The first is the use of a multiobjective optimization strategy to help identify potential morphing features that uses an existing aircraft sizing code to predict the weight, size and performance of several fixed-geometry aircraft that are Pareto-optimal based upon on two competing aircraft performance objectives. The second area has been titled morphing as an independent variable and formulates the sizing of a morphing aircraft as an optimization problem in which the amount of geometric morphing for various aircraft parameters are included as design variables. This second effort consumed most of the overall effort on the project. The third area involved a more detailed sizing study of a commercial transport aircraft that would incorporate a morphing wing to possibly enable transatlantic point-to-point passenger service.

  20. Preliminary design method for deployable spacecraft beams

    NASA Technical Reports Server (NTRS)

    Mikulas, Martin M., Jr.; Cassapakis, Costas

    1995-01-01

    There is currently considerable interest in low-cost, lightweight, compactly packageable deployable elements for various future missions involving small spacecraft. These elements must also have a simple and reliable deployment scheme and possess zero or very small free-play. Although most small spacecraft do not experience large disturbances, very low stiffness appendages or free-play can couple with even small disturbances and lead to unacceptably large attitude errors which may involve the introduction of a flexible-body control system. A class of structures referred to as 'rigidized structures' offers significant promise in providing deployable elements that will meet these needs for small spacecraft. The purpose of this paper is to introduce several rigidizable concepts and to develop a design methodology which permits a rational comparison of these elements to be made with alternate concepts.

  1. Method for designing and controlling compliant gripper

    NASA Astrophysics Data System (ADS)

    Spanu, A. R.; Besnea, D.; Avram, M.; Ciobanu, R.

    2016-08-01

    The compliant grippers are useful for high accuracy grasping of small objects with adaptive control of contact points along the active surfaces of the fingers. The spatial trajectories of the elements become a must, due to the development of MEMS. The paper presents the solution for the compliant gripper designed by the authors, so the planar and spatial movements are discussed. At the beginning of the process, the gripper could work as passive one just for the moment when it has to reach out the object surface. The forces provided by the elements have to avoid the damage. As part of the system, the camera is taken picture of the object, in order to facilitate the positioning of the system. When the contact is established, the mechanism is acting as an active gripper by using an electrical stepper motor, which has controlled movement.

  2. A flexible layout design method for passive micromixers.

    PubMed

    Deng, Yongbo; Liu, Zhenyu; Zhang, Ping; Liu, Yongshun; Gao, Qingyong; Wu, Yihui

    2012-10-01

    This paper discusses a flexible layout design method of passive micromixers based on the topology optimization of fluidic flows. Being different from the trial and error method, this method obtains the detailed layout of a passive micromixer according to the desired mixing performance by solving a topology optimization problem. Therefore, the dependence on the experience of the designer is weaken, when this method is used to design a passive micromixer with acceptable mixing performance. Several design disciplines for the passive micromixers are considered to demonstrate the flexibility of the layout design method for passive micromixers. These design disciplines include the approximation of the real 3D micromixer, the manufacturing feasibility, the spacial periodic design, and effects of the Péclet number and Reynolds number on the designs obtained by this layout design method. The capability of this design method is validated by several comparisons performed between the obtained layouts and the optimized designs in the recently published literatures, where the values of the mixing measurement is improved up to 40.4% for one cycle of the micromixer.

  3. Comparison of Traditional Design Nonlinear Programming Optimization and Stochastic Methods for Structural Design

    NASA Technical Reports Server (NTRS)

    Patnaik, Surya N.; Pai, Shantaram S.; Coroneos, Rula M.

    2010-01-01

    Structural design generated by traditional method, optimization method and the stochastic design concept are compared. In the traditional method, the constraints are manipulated to obtain the design and weight is back calculated. In design optimization, the weight of a structure becomes the merit function with constraints imposed on failure modes and an optimization algorithm is used to generate the solution. Stochastic design concept accounts for uncertainties in loads, material properties, and other parameters and solution is obtained by solving a design optimization problem for a specified reliability. Acceptable solutions were produced by all the three methods. The variation in the weight calculated by the methods was modest. Some variation was noticed in designs calculated by the methods. The variation may be attributed to structural indeterminacy. It is prudent to develop design by all three methods prior to its fabrication. The traditional design method can be improved when the simplified sensitivities of the behavior constraint is used. Such sensitivity can reduce design calculations and may have a potential to unify the traditional and optimization methods. Weight versus reliabilitytraced out an inverted-S-shaped graph. The center of the graph corresponded to mean valued design. A heavy design with weight approaching infinity could be produced for a near-zero rate of failure. Weight can be reduced to a small value for a most failure-prone design. Probabilistic modeling of load and material properties remained a challenge.

  4. Studies on Aircraft Conceptual Design Incorporating Boundary Element Method for University Design Education

    NASA Astrophysics Data System (ADS)

    Kawai, Toshiyuki; Rinoie, Kenichi

    Aircraft conceptual design method currently used for the university design education mainly utilises empirical values based on the statistical database to determine the main design parameters. Therefore, it is often difficult for students to understand the effects of aerodynamic parameters such as a wing aspect ratio and a taper ratio during the design process. In this paper, a conceptual design method that incorporates a boundary element method is discussed so that aerodynamic characteristic estimations are possible and that the students can easily comprehend the effects of aerodynamic parameters while designing the airplane. A single engine light airplane has been designed by the present conceptual design method. The results obtained by the present method and those by the conventional method are compared and discussed.

  5. The Application of Climate Risk Informed Decision Analysis to the Ioland Water Treatment Plant in Lusaka, Zambia

    NASA Astrophysics Data System (ADS)

    Kucharski, John; Tkach, Mark; Olszewski, Jennifer; Chaudhry, Rabia; Mendoza, Guillermo

    2016-04-01

    This presentation demonstrates the application of Climate Risk Informed Decision Analysis (CRIDA) at Zambia's principal water treatment facility, The Iolanda Water Treatment Plant. The water treatment plant is prone to unacceptable failures during periods of low hydropower production at the Kafue Gorge Dam Hydroelectric Power Plant. The case study explores approaches of increasing the water treatment plant's ability to deliver acceptable levels of service under the range of current and potential future climate states. The objective of the study is to investigate alternative investments to build system resilience that might have been informed by the CRIDA process, and to evaluate the extra resource requirements by a bilateral donor agency to implement the CRIDA process. The case study begins with an assessment of the water treatment plant's vulnerability to climate change. It does so by following general principals described in "Confronting Climate Uncertainty in Water Resource Planning and Project Design: the Decision Tree Framework". By utilizing relatively simple bootstrapping methods a range of possible future climate states is generated while avoiding the use of more complex and costly downscaling methodologies; that are beyond the budget and technical capacity of many teams. The resulting climate vulnerabilities and uncertainty in the climate states that produce them are analyzed as part of a "Level of Concern" analysis. CRIDA principals are then applied to this Level of Concern analysis in order to arrive at a set of actionable water management decisions. The principal goals of water resource management is to transform variable, uncertain hydrology into dependable services (e.g. water supply, flood risk reduction, ecosystem benefits, hydropower production, etc…). Traditional approaches to climate adaptation require the generation of predicted future climate states but do little guide decision makers how this information should impact decision making. In

  6. Conceptual design of clean processes: Tools and methods

    SciTech Connect

    Hurme, M.

    1996-12-31

    Design tools available for implementing clean design into practice are discussed. The application areas together with the methods of comparison of clean process alternatives are presented. Environmental principles are becoming increasingly important in the whole life cycle of products from design, manufacturing and marketing to disposal. The hinder of implementing clean technology in design has been the necessity to apply it in all phases of design starting from the beginning, since it deals with the major selections made in the conceptual process design. Therefore both a modified design approach and new tools are needed for process design to make the application of clean technology practical. The first item; extended process design methodologies has been presented by Hurme, Douglas, Rossiter and Klee, Hilaly and Sikdar. The aim of this paper is to discuss the latter topic; the process design tools which assist in implementing clean principles into process design. 22 refs., 2 tabs.

  7. Analytical techniques for instrument design - matrix methods

    SciTech Connect

    Robinson, R.A.

    1997-09-01

    We take the traditional Cooper-Nathans approach, as has been applied for many years for steady-state triple-axis spectrometers, and consider its generalisation to other inelastic scattering spectrometers. This involves a number of simple manipulations of exponentials of quadratic forms. In particular, we discuss a toolbox of matrix manipulations that can be performed on the 6- dimensional Cooper-Nathans matrix: diagonalisation (Moller-Nielsen method), coordinate changes e.g. from ({Delta}k{sub I},{Delta}k{sub F} to {Delta}E, {Delta}Q & 2 dummy variables), integration of one or more variables (e.g. over such dummy variables), integration subject to linear constraints (e.g. Bragg`s Law for analysers), inversion to give the variance-covariance matrix, and so on. We show how these tools can be combined to solve a number of important problems, within the narrow-band limit and the gaussian approximation. We will argue that a generalised program that can handle multiple different spectrometers could (and should) be written in parallel to the Monte-Carlo packages that are becoming available. We will also discuss the complementarity between detailed Monte-Carlo calculations and the approach presented here. In particular, Monte-Carlo methods traditionally simulate the real experiment as performed in practice, given a model scattering law, while the Cooper-Nathans method asks the inverse question: given that a neutron turns up in a particular spectrometer configuration (e.g. angle and time of flight), what is the probability distribution of possible scattering events at the sample? The Monte-Carlo approach could be applied in the same spirit to this question.

  8. Aqueduct Global Flood Analyzer - bringing risk information to practice

    NASA Astrophysics Data System (ADS)

    Ward, P.; Bierkens, M. F.; Bouwman, A.; Diaz Loaiza, A.; Eilander, D.; Englhardt, J.; Erkens, G.; Hofste, R.; Iceland, C.; Willem, L.; Luo, T.; Muis, S.; Scussolini, P.; Sutanudjaja, E.; Van Beek, L. P.; Van Bemmel, B.; Van Huijstee, J.; Van Wesenbeeck, B.; Vatvani, D.; Verlaan, M.; Winsemius, H.

    2016-12-01

    The economic losses associated with flooding are huge and rising. As a result, there is increasing attention for strategic flood risk assessments at the global scale. In response, the last few years have seen a large growth in the number of global flood models. At the same time, users and practitioners require flood risk information in a format that is easy to use, understandable, transparent, and actionable. In response, we have developed the Aqueduct Global Flood Analyzer (wri.org/floods). The Analyzer is a free, online, easy to use, tool for assessing global river flood risk at the scale of countries, states, and river basins, using data generated by the state of the art GLOFRIS global flood risk model. The Analyzer allows users to assess flood risk on-the-fly in terms of expected annual urban damage, and expected annual population and GDP affected by floods. Analyses can be carried out for current conditions and under future scenarios of climate change and socioeconomic development. We will demonstrate the tool, and discuss several of its applications in practice. In the past 15 months, the tool has been visited and used by more than 12,000 unique users from almost every country, including many users from the World Bank, Pacific Disaster Center, Red Cross Climate Centre, as well as many journalists from major international news outlets. Use cases will be presented from these user communities. We will also present ongoing research to improve the user functionality of the tool in the coming year. This includes the inclusion of coastal flood risk, assessing the costs and benefits of adaptation, and assessing the impacts of land subsidence and urban extension on risk.

  9. Aqueduct Global Flood Analyzer - bringing risk information to practice

    NASA Astrophysics Data System (ADS)

    Ward, Philip

    2017-04-01

    The economic losses associated with flooding are huge and rising. As a result, there is increasing attention for strategic flood risk assessments at the global scale. In response, the last few years have seen a large growth in the number of global flood models. At the same time, users and practitioners require flood risk information in a format that is easy to use, understandable, transparent, and actionable. In response, we have developed the Aqueduct Global Flood Analyzer (wri.org/floods). The Analyzer is a free, online, easy to use, tool for assessing global river flood risk at the scale of countries, states, and river basins, using data generated by the state of the art GLOFRIS global flood risk model. The Analyzer allows users to assess flood risk on-the-fly in terms of expected annual urban damage, and expected annual population and GDP affected by floods. Analyses can be carried out for current conditions and under future scenarios of climate change and socioeconomic development. We will demonstrate the tool, and discuss several of its applications in practice. In the past 15 months, the tool has been visited and used by more than 12,000 unique users from almost every country, including many users from the World Bank, Pacific Disaster Center, Red Cross Climate Centre, as well as many journalists from major international news outlets. Use cases will be presented from these user communities. We will also present ongoing research to improve the user functionality of the tool in the coming year. This includes the inclusion of coastal flood risk, assessing the costs and benefits of adaptation, and assessing the impacts of land subsidence and urban extension on risk.

  10. HEALTHY study rationale, design and methods

    PubMed Central

    2009-01-01

    The HEALTHY primary prevention trial was designed and implemented in response to the growing numbers of children and adolescents being diagnosed with type 2 diabetes. The objective was to moderate risk factors for type 2 diabetes. Modifiable risk factors measured were indicators of adiposity and glycemic dysregulation: body mass index ≥85th percentile, fasting glucose ≥5.55 mmol l-1 (100 mg per 100 ml) and fasting insulin ≥180 pmol l-1 (30 μU ml-1). A series of pilot studies established the feasibility of performing data collection procedures and tested the development of an intervention consisting of four integrated components: (1) changes in the quantity and nutritional quality of food and beverage offerings throughout the total school food environment; (2) physical education class lesson plans and accompanying equipment to increase both participation and number of minutes spent in moderate-to-vigorous physical activity; (3) brief classroom activities and family outreach vehicles to increase knowledge, enhance decision-making skills and support and reinforce youth in accomplishing goals; and (4) communications and social marketing strategies to enhance and promote changes through messages, images, events and activities. Expert study staff provided training, assistance, materials and guidance for school faculty and staff to implement the intervention components. A cohort of students were enrolled in sixth grade and followed to end of eighth grade. They attended a health screening data collection at baseline and end of study that involved measurement of height, weight, blood pressure, waist circumference and a fasting blood draw. Height and weight were also collected at the end of the seventh grade. The study was conducted in 42 middle schools, six at each of seven locations across the country, with 21 schools randomized to receive the intervention and 21 to act as controls (data collection activities only). Middle school was the unit of sample size and

  11. Analyses in support of risk-informed natural gas vehicle maintenance facility codes and standards :

    SciTech Connect

    Ekoto, Isaac W.; Blaylock, Myra L.; LaFleur, Angela Christine; LaChance, Jeffrey L.; Horne, Douglas B.

    2014-03-01

    Safety standards development for maintenance facilities of liquid and compressed gas fueled large-scale vehicles is required to ensure proper facility design and operation envelopes. Standard development organizations are utilizing risk-informed concepts to develop natural gas vehicle (NGV) codes and standards so that maintenance facilities meet acceptable risk levels. The present report summarizes Phase I work for existing NGV repair facility code requirements and highlights inconsistencies that need quantitative analysis into their effectiveness. A Hazardous and Operability study was performed to identify key scenarios of interest. Finally, scenario analyses were performed using detailed simulations and modeling to estimate the overpressure hazards from HAZOP defined scenarios. The results from Phase I will be used to identify significant risk contributors at NGV maintenance facilities, and are expected to form the basis for follow-on quantitative risk analysis work to address specific code requirements and identify effective accident prevention and mitigation strategies.

  12. System and method of designing models in a feedback loop

    DOEpatents

    Gosink, Luke C.; Pulsipher, Trenton C.; Sego, Landon H.

    2017-02-14

    A method and system for designing models is disclosed. The method includes selecting a plurality of models for modeling a common event of interest. The method further includes aggregating the results of the models and analyzing each model compared to the aggregate result to obtain comparative information. The method also includes providing the information back to the plurality of models to design more accurate models through a feedback loop.

  13. What Can Mixed Methods Designs Offer Professional Development Program Evaluators?

    ERIC Educational Resources Information Center

    Giordano, Victoria; Nevin, Ann

    2007-01-01

    In this paper, the authors describe the benefits and pitfalls of mixed methods designs. They argue that mixed methods designs may be preferred when evaluating professional development programs for p-K-12 education given the new call for accountability in making data-driven decisions. They summarize and critique the studies in terms of limitations…

  14. 14 CFR 161.9 - Designation of noise description methods.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Designation of noise description methods... TRANSPORTATION (CONTINUED) AIRPORTS NOTICE AND APPROVAL OF AIRPORT NOISE AND ACCESS RESTRICTIONS General Provisions § 161.9 Designation of noise description methods. For purposes of this part, the following...

  15. 14 CFR 161.9 - Designation of noise description methods.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Designation of noise description methods... TRANSPORTATION (CONTINUED) AIRPORTS NOTICE AND APPROVAL OF AIRPORT NOISE AND ACCESS RESTRICTIONS General Provisions § 161.9 Designation of noise description methods. For purposes of this part, the following...

  16. 14 CFR 161.9 - Designation of noise description methods.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Designation of noise description methods... TRANSPORTATION (CONTINUED) AIRPORTS NOTICE AND APPROVAL OF AIRPORT NOISE AND ACCESS RESTRICTIONS General Provisions § 161.9 Designation of noise description methods. For purposes of this part, the following...

  17. 14 CFR 161.9 - Designation of noise description methods.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Designation of noise description methods... TRANSPORTATION (CONTINUED) AIRPORTS NOTICE AND APPROVAL OF AIRPORT NOISE AND ACCESS RESTRICTIONS General Provisions § 161.9 Designation of noise description methods. For purposes of this part, the following...

  18. 14 CFR 161.9 - Designation of noise description methods.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Designation of noise description methods... TRANSPORTATION (CONTINUED) AIRPORTS NOTICE AND APPROVAL OF AIRPORT NOISE AND ACCESS RESTRICTIONS General Provisions § 161.9 Designation of noise description methods. For purposes of this part, the following...

  19. A design method of divertor in tokamak reactors

    NASA Astrophysics Data System (ADS)

    Ueda, N.; Itoh, S.-I.; Tanaka, M.; Itoh, K.

    1990-08-01

    Computational method to design the efficient divertor configuration in tokamak reactor is presented. The two dimensional code was developed to analyze the distributions of the plasma and neutral particles for realistic configurations. Using this code, a method to design the efficient divertor configuration is developed. An example of new divertor, which consists of the baffle and fin plates, is analyzed.

  20. Probabilistic Methods for Uncertainty Propagation Applied to Aircraft Design

    NASA Technical Reports Server (NTRS)

    Green, Lawrence L.; Lin, Hong-Zong; Khalessi, Mohammad R.

    2002-01-01

    Three methods of probabilistic uncertainty propagation and quantification (the method of moments, Monte Carlo simulation, and a nongradient simulation search method) are applied to an aircraft analysis and conceptual design program to demonstrate design under uncertainty. The chosen example problems appear to have discontinuous design spaces and thus these examples pose difficulties for many popular methods of uncertainty propagation and quantification. However, specific implementation features of the first and third methods chosen for use in this study enable successful propagation of small uncertainties through the program. Input uncertainties in two configuration design variables are considered. Uncertainties in aircraft weight are computed. The effects of specifying required levels of constraint satisfaction with specified levels of input uncertainty are also demonstrated. The results show, as expected, that the designs under uncertainty are typically heavier and more conservative than those in which no input uncertainties exist.

  1. Analyzing disease recurrence with missing at risk information.

    PubMed

    Štupnik, Tomaž; Pohar Perme, Maja

    2016-03-30

    When analyzing time to disease recurrence, we sometimes need to work with data where all the recurrences are recorded, but no information is available on the possible deaths. This may occur when studying diseases of benign nature where patients are only seen at disease recurrences or in poorly-designed registries of benign diseases or medical device implantations without sufficient patient identifiers to obtain their dead/alive status at a later date. When the average time to disease recurrence is long enough in comparison with the expected survival of the patients, statistical analysis of such data can be significantly biased. Under the assumption that the expected survival of an individual is not influenced by the disease itself, general population mortality tables may be used to remove this bias. We show why the intuitive solution of simply imputing the patient's expected survival time does not give unbiased estimates of the usual quantities of interest in survival analysis and further explain that cumulative incidence function analysis does not require additional assumptions on general population mortality. We provide an alternative framework that allows unbiased estimation and introduce two new approaches: an iterative imputation method and a mortality adjusted at risk function. Their properties are carefully studied, with the results supported by simulations and illustrated on a real-world example.

  2. Expanding color design methods for architecture and allied disciplines

    NASA Astrophysics Data System (ADS)

    Linton, Harold E.

    2002-06-01

    The color design processes of visual artists, architects, designers, and theoreticians included in this presentation reflect the practical role of color in architecture. What the color design professional brings to the architectural design team is an expertise and rich sensibility made up of a broad awareness and a finely tuned visual perception. This includes a knowledge of design and its history, expertise with industrial color materials and their methods of application, an awareness of design context and cultural identity, a background in physiology and psychology as it relates to human welfare, and an ability to problem-solve and respond creatively to design concepts with innovative ideas. The broadening of the definition of the colorists's role in architectural design provides architects, artists and designers with significant opportunities for continued professional and educational development.

  3. Designing Adaptive Intensive Interventions Using Methods from Engineering

    PubMed Central

    Lagoa, Constantino M.; Bekiroglu, Korkut; Lanza, Stephanie T.; Murphy, Susan A.

    2014-01-01

    Objective Adaptive intensive interventions are introduced and new methods from the field of control engineering for use in their design are illustrated. Method A detailed step-by-step explanation of how control engineering methods can be used with intensive longitudinal data to design an adaptive intensive intervention is provided. The methods are evaluated via simulation. Results Simulation results illustrate how the designed adaptive intensive intervention can result in improved outcomes with less treatment by providing treatment only when it is needed. Furthermore, the methods are robust to model misspecification as well as the influence of unobserved causes. Conclusions These new methods can be used to design adaptive interventions that are effective yet reduce participant burden. PMID:25244394

  4. A simple inverse design method for pump turbine

    NASA Astrophysics Data System (ADS)

    Yin, Junlian; Li, Jingjing; Wang, Dezhong; Wei, Xianzhu

    2014-03-01

    In this paper, a simple inverse design method is proposed for pump turbine. The main point of this method is that the blade loading distribution is first extracted from an existing model and then applied in the new design. As an example, the blade loading distribution of the runner designed with head 200m, was analyzed. And then, the combination of the extracted blade loading and a meridional passage suitable for 500m head is applied to design a new runner project. After CFD and model test, it is shown that the new runner performs very well in terms of efficiency and cavitation. Therefore, as an alternative, the inverse design method can be extended to other design applications.

  5. Design methods for fault-tolerant finite state machines

    NASA Technical Reports Server (NTRS)

    Niranjan, Shailesh; Frenzel, James F.

    1993-01-01

    VLSI electronic circuits are increasingly being used in space-borne applications where high levels of radiation may induce faults, known as single event upsets. In this paper we review the classical methods of designing fault tolerant digital systems, with an emphasis on those methods which are particularly suitable for VLSI-implementation of finite state machines. Four methods are presented and will be compared in terms of design complexity, circuit size, and estimated circuit delay.

  6. Review of design optimization methods for turbomachinery aerodynamics

    NASA Astrophysics Data System (ADS)

    Li, Zhihui; Zheng, Xinqian

    2017-08-01

    In today's competitive environment, new turbomachinery designs need to be not only more efficient, quieter, and ;greener; but also need to be developed at on much shorter time scales and at lower costs. A number of advanced optimization strategies have been developed to achieve these requirements. This paper reviews recent progress in turbomachinery design optimization to solve real-world aerodynamic problems, especially for compressors and turbines. This review covers the following topics that are important for optimizing turbomachinery designs. (1) optimization methods, (2) stochastic optimization combined with blade parameterization methods and the design of experiment methods, (3) gradient-based optimization methods for compressors and turbines and (4) data mining techniques for Pareto Fronts. We also present our own insights regarding the current research trends and the future optimization of turbomachinery designs.

  7. Inviscid transonic wing design using inverse methods in curvilinear coordinates

    NASA Technical Reports Server (NTRS)

    Gally, Thomas A.; Carlson, Leland A.

    1987-01-01

    An inverse wing design method has been developed around an existing transonic wing analysis code. The original analysis code, TAWFIVE, has as its core the numerical potential flow solver, FLO30, developed by Jameson and Caughey. Features of the analysis code include a finite-volume formulation; wing and fuselage fitted, curvilinear grid mesh; and a viscous boundary layer correction that also accounts for viscous wake thickness and curvature. The development of the inverse methods as an extension of previous methods existing for design in Cartesian coordinates is presented. Results are shown for inviscid wing design cases in super-critical flow regimes. The test cases selected also demonstrate the versatility of the design method in designing an entire wing or discontinuous sections of a wing.

  8. System Design Support by Optimization Method Using Stochastic Process

    NASA Astrophysics Data System (ADS)

    Yoshida, Hiroaki; Yamaguchi, Katsuhito; Ishikawa, Yoshio

    We proposed the new optimization method based on stochastic process. The characteristics of this method are to obtain the approximate solution of the optimum solution as an expected value. In numerical calculation, a kind of Monte Carlo method is used to obtain the solution because of stochastic process. Then, it can obtain the probability distribution of the design variable because it is generated in the probability that design variables were in proportion to the evaluation function value. This probability distribution shows the influence of design variables on the evaluation function value. This probability distribution is the information which is very useful for the system design. In this paper, it is shown the proposed method is useful for not only the optimization but also the system design. The flight trajectory optimization problem for the hang-glider is shown as an example of the numerical calculation.

  9. Tabu search method with random moves for globally optimal design

    NASA Astrophysics Data System (ADS)

    Hu, Nanfang

    1992-09-01

    Optimum engineering design problems are usually formulated as non-convex optimization problems of continuous variables. Because of the absence of convexity structure, they can have multiple minima, and global optimization becomes difficult. Traditional methods of optimization, such as penalty methods, can often be trapped at a local optimum. The tabu search method with random moves to solve approximately these problems is introduced. Its reliability and efficiency are examined with the help of standard test functions. By the analysis of the implementations, it is seen that this method is easy to use, and no derivative information is necessary. It outperforms the random search method and composite genetic algorithm. In particular, it is applied to minimum weight design examples of a three-bar truss, coil springs, a Z-section and a channel section. For the channel section, the optimal design using the tabu search method with random moves saved 26.14 percent over the weight of the SUMT method.

  10. Designing adaptive intensive interventions using methods from engineering.

    PubMed

    Lagoa, Constantino M; Bekiroglu, Korkut; Lanza, Stephanie T; Murphy, Susan A

    2014-10-01

    Adaptive intensive interventions are introduced, and new methods from the field of control engineering for use in their design are illustrated. A detailed step-by-step explanation of how control engineering methods can be used with intensive longitudinal data to design an adaptive intensive intervention is provided. The methods are evaluated via simulation. Simulation results illustrate how the designed adaptive intensive intervention can result in improved outcomes with less treatment by providing treatment only when it is needed. Furthermore, the methods are robust to model misspecification as well as the influence of unobserved causes. These new methods can be used to design adaptive interventions that are effective yet reduce participant burden. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  11. Insight into the Earthquake Risk Information Seeking Behavior of the Victims: Evidence from Songyuan, China.

    PubMed

    Li, Shasha; Zhai, Guofang; Zhou, Shutian; Fan, Chenjing; Wu, Yunqing; Ren, Chongqiang

    2017-03-07

    Efficient risk communication is a vital way to reduce the vulnerability of individuals when facing emergency risks, especially regarding earthquakes. Efficient risk communication aims at improving the supply of risk information and fulfilling the need for risk information by individuals. Therefore, an investigation into individual-level information seeking behavior within earthquake risk contexts is very important for improved earthquake risk communication. However, at present there are very few studies that have explored the behavior of individuals seeking earthquake risk information. Under the guidance of the Risk Information Seeking and Processing model as well as relevant practical findings using the structural equation model, this study attempts to explore the main determinants of an individual's earthquake risk information seeking behavior, and to validate the mediator effect of information need during the seeking process. A questionnaire-based survey of 918 valid respondents in Songyuan, China, who had been hit by a small earthquake swarm, was used to provide practical evidence for this study. Results indicated that information need played a noteworthy role in the earthquake risk information seeking process, and was detected both as an immediate predictor and as a mediator. Informational subjective norms drive the seeking behavior on earthquake risk information through both direct and indirect approaches. Perceived information gathering capacity, negative affective responses and risk perception have an indirect effect on earthquake risk information seeking behavior via information need. The implications for theory and practice regarding risk communication are discussed and concluded.

  12. Insight into the Earthquake Risk Information Seeking Behavior of the Victims: Evidence from Songyuan, China

    PubMed Central

    Li, Shasha; Zhai, Guofang; Zhou, Shutian; Fan, Chenjing; Wu, Yunqing; Ren, Chongqiang

    2017-01-01

    Efficient risk communication is a vital way to reduce the vulnerability of individuals when facing emergency risks, especially regarding earthquakes. Efficient risk communication aims at improving the supply of risk information and fulfilling the need for risk information by individuals. Therefore, an investigation into individual-level information seeking behavior within earthquake risk contexts is very important for improved earthquake risk communication. However, at present there are very few studies that have explored the behavior of individuals seeking earthquake risk information. Under the guidance of the Risk Information Seeking and Processing model as well as relevant practical findings using the structural equation model, this study attempts to explore the main determinants of an individual’s earthquake risk information seeking behavior, and to validate the mediator effect of information need during the seeking process. A questionnaire-based survey of 918 valid respondents in Songyuan, China, who had been hit by a small earthquake swarm, was used to provide practical evidence for this study. Results indicated that information need played a noteworthy role in the earthquake risk information seeking process, and was detected both as an immediate predictor and as a mediator. Informational subjective norms drive the seeking behavior on earthquake risk information through both direct and indirect approaches. Perceived information gathering capacity, negative affective responses and risk perception have an indirect effect on earthquake risk information seeking behavior via information need. The implications for theory and practice regarding risk communication are discussed and concluded. PMID:28272359

  13. Robust Multivariable Controller Design via Implicit Model-Following Methods.

    DTIC Science & Technology

    1983-12-01

    HD-Ri38 309 ROBUST MULTIVARIABLE CONTROLLER DESIGN VIA IMPLICIT 1/4 MODEL-FOLLOWING METHODS(U) AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL...aaS. a%. 1 .111 I Q~ 18 0 ROBUST MULTIVARIABLE CONTROLLER DESIGN -~ :VIA IMPLICIT MODEL-FOLLOWING METHODS ’.% THESIS , AFIT/GE/EE/83D-48 William G... CONTROLLER DESIGN VIA IMPLICIT MODEL-FOLLOWING METHODS THESIS AFIT/GE/EE/83D-48 William G. Miller Capt USAF ,. Approved for pubi release; distribution

  14. An inverse method with regularity condition for transonic airfoil design

    NASA Technical Reports Server (NTRS)

    Zhu, Ziqiang; Xia, Zhixun; Wu, Liyi

    1991-01-01

    It is known from Lighthill's exact solution of the incompressible inverse problem that in the inverse design problem, the surface pressure distribution and the free stream speed cannot both be prescribed independently. This implies the existence of a constraint on the prescribed pressure distribution. The same constraint exists at compressible speeds. Presented here is an inverse design method for transonic airfoils. In this method, the target pressure distribution contains a free parameter that is adjusted during the computation to satisfy the regularity condition. Some design results are presented in order to demonstrate the capabilities of the method.

  15. Design of freeform unobscured reflective imaging systems using CI method

    NASA Astrophysics Data System (ADS)

    Yang, Tong; Hou, Wei; Wu, Xiaofei; Jin, Guofan; Zhu, Jun

    2016-10-01

    In this paper, we demonstrated the design method of freeform unobscured reflective imaging systems using the point-bypoint Construction-Iteration (CI) method. Compared with other point-by-point design methods, the light rays of multiple fields and different pupil coordinates are employed in the design. The whole design process starts from a simple initial system consisting of decentered and tilted planes. In the preliminary surfaces-construction stage, the coordinates as well as the surface normals of the feature data points on each freeform surface can be calculated point-by-point directly based on the given object-image relationships. Then, the freeform surfaces are generated through a novel surface fitting method considering both the coordinates and surface normals of the data points. Next, an iterative process is employed to significantly improve the image quality. In this way, an unobscured design with freeform surfaces can be obtained directly, and it can be taken as a good starting point for further optimization. The benefit and feasibility of this design method is demonstrated by two design examples of high-performance freeform unobscured imaging systems. Both two systems have good imaging performance after final design.

  16. Design Method for EPS Control System Based on KANSEI Structure

    NASA Astrophysics Data System (ADS)

    Saitoh, Yumi; Itoh, Hideaki; Ozaki, Fuminori; Nakamura, Takenobu; Kawaji, Shigeyasu

    Recently, it has been identified that a KANSEI engineering plays an important role in functional design developing for realizing highly sophisticated products. However, in practical development methods, we design products and optimise the design trial and error, which indecates that we depend on the skill set of experts. In this paper, we focus on an automobile electric power steering (EPS) for which a functional design is required. First, the KANSEI structure is determined on the basis of the steering feeling of an experienced driver, and an EPS control design based on this KANSEI structure is proposed. Then, the EPS control parameters are adjusted in accordance with the KANSEI index. Finally, by assessing the experimental results obtained from the driver, the effectiveness of the proposed design method is verified.

  17. Single-Case Designs and Qualitative Methods: Applying a Mixed Methods Research Perspective

    ERIC Educational Resources Information Center

    Hitchcock, John H.; Nastasi, Bonnie K.; Summerville, Meredith

    2010-01-01

    The purpose of this conceptual paper is to describe a design that mixes single-case (sometimes referred to as single-subject) and qualitative methods, hereafter referred to as a single-case mixed methods design (SCD-MM). Minimal attention has been given to the topic of applying qualitative methods to SCD work in the literature. These two…

  18. Single-Case Designs and Qualitative Methods: Applying a Mixed Methods Research Perspective

    ERIC Educational Resources Information Center

    Hitchcock, John H.; Nastasi, Bonnie K.; Summerville, Meredith

    2010-01-01

    The purpose of this conceptual paper is to describe a design that mixes single-case (sometimes referred to as single-subject) and qualitative methods, hereafter referred to as a single-case mixed methods design (SCD-MM). Minimal attention has been given to the topic of applying qualitative methods to SCD work in the literature. These two…

  19. An artificial viscosity method for the design of supercritical airfoils

    NASA Technical Reports Server (NTRS)

    Mcfadden, G. B.

    1979-01-01

    A numerical technique is presented for the design of two-dimensional supercritical wing sections with low wave drag. The method is a design mode of the analysis code H which gives excellent agreement with experimental results and is widely used in the aircraft industry. Topics covered include the partial differential equations of transonic flow, the computational procedure and results; the design procedure; a convergence theorem; and description of the code.

  20. Stabilizing State-Feedback Design via the Moving Horizon Method.

    DTIC Science & Technology

    1982-01-01

    aide if necessary and identify by block number) Stabilizing control design; linear time varying systems; fixed depth horizon; index optimization methods...dual system. 20. ABSTRACT (Continue an reverse side If necessary and Identify by block number) Li _ A stabilizing control design for general linear...Apprvyed for pb~ ~~* 14 ~dl Stri but ion uni imit Oe, ABSTRACT A stabilizing control design for general linear time vary- invariant systems through

  1. Numerical methods for aerothermodynamic design of hypersonic space transport vehicles

    NASA Astrophysics Data System (ADS)

    Wanie, K. M.; Brenneis, A.; Eberle, A.; Heiss, S.

    1993-04-01

    The requirement of the design process of hypersonic vehicles to predict flow past entire configurations with wings, fins, flaps, and propulsion system represents one of the major challenges for aerothermodynamics. In this context computational fluid dynamics has come up as a powerful tool to support the experimental work. A couple of numerical methods developed at MBB designed to fulfill the needs of the design process are described. The governing equations and fundamental details of the solution methods are shortly reviewed. Results are given for both geometrically simple test cases and realistic hypersonic configurations. Since there is still a considerable lack of experience for hypersonic flow calculations an extensive testing and verification is essential. This verification is done by comparison of results with experimental data and other numerical methods. The results presented prove that the methods used are robust, flexible, and accurate enough to fulfill the strong needs of the design process.

  2. Working stress design method for reinforced soil walls

    SciTech Connect

    Ehrlich, M. ); Mitchell, J.K. )

    1994-04-01

    A method for the internal design of reinforced soil walls based on working stresses is developed and evaluated using measurements from five full-scale structures containing a range of reinforcement types. It is shown that, in general, the stiffer the reinforcement system and the higher the stresses induced during compaction, the higher are the tensile stresses that must be resisted by the reinforcements. Unique features of this method, compared to currently used reinforced soil wall design methods, are that it can be applied to all types of reinforcement systems, reinforcement and soil stiffness properties are considered, and backfill compaction stresses are taken explicitly into account. The method can be applied either analytically or using design charts. A design example is included.

  3. Two-Method Planned Missing Designs for Longitudinal Research

    ERIC Educational Resources Information Center

    Garnier-Villarreal, Mauricio; Rhemtulla, Mijke; Little, Todd D.

    2014-01-01

    We examine longitudinal extensions of the two-method measurement design, which uses planned missingness to optimize cost-efficiency and validity of hard-to-measure constructs. These designs use a combination of two measures: a "gold standard" that is highly valid but expensive to administer, and an inexpensive (e.g., survey-based)…

  4. New directions for Artificial Intelligence (AI) methods in optimum design

    NASA Technical Reports Server (NTRS)

    Hajela, Prabhat

    1989-01-01

    Developments and applications of artificial intelligence (AI) methods in the design of structural systems is reviewed. Principal shortcomings in the current approach are emphasized, and the need for some degree of formalism in the development environment for such design tools is underscored. Emphasis is placed on efforts to integrate algorithmic computations in expert systems.

  5. Two-Method Planned Missing Designs for Longitudinal Research

    ERIC Educational Resources Information Center

    Garnier-Villarreal, Mauricio; Rhemtulla, Mijke; Little, Todd D.

    2014-01-01

    We examine longitudinal extensions of the two-method measurement design, which uses planned missingness to optimize cost-efficiency and validity of hard-to-measure constructs. These designs use a combination of two measures: a "gold standard" that is highly valid but expensive to administer, and an inexpensive (e.g., survey-based)…

  6. Investigating the Use of Design Methods by Capstone Design Students at Clemson University

    ERIC Educational Resources Information Center

    Miller, W. Stuart; Summers, Joshua D.

    2013-01-01

    The authors describe a preliminary study to understand the attitude of engineering students regarding the use of design methods in projects to identify the factors either affecting or influencing the use of these methods by novice engineers. A senior undergraduate capstone design course at Clemson University, consisting of approximately fifty…

  7. Approximate method of designing a two-element airfoil

    NASA Astrophysics Data System (ADS)

    Abzalilov, D. F.; Mardanov, R. F.

    2011-09-01

    An approximate method is proposed for designing a two-element airfoil. The method is based on reducing an inverse boundary-value problem in a doubly connected domain to a problem in a singly connected domain located on a multisheet Riemann surface. The essence of the method is replacement of channels between the airfoil elements by channels of flow suction and blowing. The shape of these channels asymptotically tends to the annular shape of channels passing to infinity on the second sheet of the Riemann surface. The proposed method can be extended to designing multielement airfoils.

  8. New knowledge network evaluation method for design rationale management

    NASA Astrophysics Data System (ADS)

    Jing, Shikai; Zhan, Hongfei; Liu, Jihong; Wang, Kuan; Jiang, Hao; Zhou, Jingtao

    2015-01-01

    Current design rationale (DR) systems have not demonstrated the value of the approach in practice since little attention is put to the evaluation method of DR knowledge. To systematize knowledge management process for future computer-aided DR applications, a prerequisite is to provide the measure for the DR knowledge. In this paper, a new knowledge network evaluation method for DR management is presented. The method characterizes the DR knowledge value from four perspectives, namely, the design rationale structure scale, association knowledge and reasoning ability, degree of design justification support and degree of knowledge representation conciseness. The DR knowledge comprehensive value is also measured by the proposed method. To validate the proposed method, different style of DR knowledge network and the performance of the proposed measure are discussed. The evaluation method has been applied in two realistic design cases and compared with the structural measures. The research proposes the DR knowledge evaluation method which can provide object metric and selection basis for the DR knowledge reuse during the product design process. In addition, the method is proved to be more effective guidance and support for the application and management of DR knowledge.

  9. Design method for four-reflector type beam waveguide systems

    NASA Technical Reports Server (NTRS)

    Betsudan, S.; Katagi, T.; Urasaki, S.

    1986-01-01

    Discussed is a method for the design of four reflector type beam waveguide feed systems, comprised of a conical horn and 4 focused reflectors, which are used widely as the primary reflector systems for communications satellite Earth station antennas. The design parameters for these systems are clarified, the relations between each parameter are brought out based on the beam mode development, and the independent design parameters are specified. The characteristics of these systems, namely spillover loss, crosspolarization components, and frequency characteristics, and their relation to the design parameters, are also shown. It is also indicated that design parameters which decide the dimensions of the conical horn or the shape of the focused reflectors can be unerringly established once the design standard for the system has been selected as either: (1) minimizing the crosspolarization component by keeping the spillover loss to within acceptable limits, or (2) minimizing the spillover loss by maintaining the crossover components below an acceptable level and the independent design parameters, such as the respective sizes of the focused reflectors and the distances between the focussed reflectors, etc., have been established according to mechanical restrictions. A sample design is also shown. In addition to being able to clarify the effects of each of the design parameters on the system and improving insight into these systems, the efficiency of these systems will also be increased with this design method.

  10. Epidemiological designs for vaccine safety assessment: methods and pitfalls.

    PubMed

    Andrews, Nick

    2012-09-01

    Three commonly used designs for vaccine safety assessment post licensure are cohort, case-control and self-controlled case series. These methods are often used with routine health databases and immunisation registries. This paper considers the issues that may arise when designing an epidemiological study, such as understanding the vaccine safety question, case definition and finding, limitations of data sources, uncontrolled confounding, and pitfalls that apply to the individual designs. The example of MMR and autism, where all three designs have been used, is presented to help consider these issues. Copyright © 2011 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  11. A comparison of methods for DPLL loop filter design

    NASA Technical Reports Server (NTRS)

    Aguirre, S.; Hurd, W. J.; Kumar, R.; Statman, J.

    1986-01-01

    Four design methodologies for loop filters for a class of digital phase-locked loops (DPLLs) are presented. The first design maps an optimum analog filter into the digital domain; the second approach designs a filter that minimizes in discrete time weighted combination of the variance of the phase error due to noise and the sum square of the deterministic phase error component; the third method uses Kalman filter estimation theory to design a filter composed of a least squares fading memory estimator and a predictor. The last design relies on classical theory, including rules for the design of compensators. Linear analysis is used throughout the article to compare different designs, and includes stability, steady state performance and transient behavior of the loops. Design methodology is not critical when the loop update rate can be made high relative to loop bandwidth, as the performance approaches that of continuous time. For low update rates, however, the miminization method is significantly superior to the other methods.

  12. A comparison of methods for DPLL loop filter design

    NASA Astrophysics Data System (ADS)

    Aguirre, S.; Hurd, W. J.; Kumar, R.; Statman, J.

    1986-11-01

    Four design methodologies for loop filters for a class of digital phase-locked loops (DPLLs) are presented. The first design maps an optimum analog filter into the digital domain; the second approach designs a filter that minimizes in discrete time weighted combination of the variance of the phase error due to noise and the sum square of the deterministic phase error component; the third method uses Kalman filter estimation theory to design a filter composed of a least squares fading memory estimator and a predictor. The last design relies on classical theory, including rules for the design of compensators. Linear analysis is used throughout the article to compare different designs, and includes stability, steady state performance and transient behavior of the loops. Design methodology is not critical when the loop update rate can be made high relative to loop bandwidth, as the performance approaches that of continuous time. For low update rates, however, the miminization method is significantly superior to the other methods.

  13. Novel parameter-based flexure bearing design method

    NASA Astrophysics Data System (ADS)

    Amoedo, Simon; Thebaud, Edouard; Gschwendtner, Michael; White, David

    2016-06-01

    A parameter study was carried out on the design variables of a flexure bearing to be used in a Stirling engine with a fixed axial displacement and a fixed outer diameter. A design method was developed in order to assist identification of the optimum bearing configuration. This was achieved through a parameter study of the bearing carried out with ANSYS®. The parameters varied were the number and the width of the arms, the thickness of the bearing, the eccentricity, the size of the starting and ending holes, and the turn angle of the spiral. Comparison was made between the different designs in terms of axial and radial stiffness, the natural frequency, and the maximum induced stresses. Moreover, the Finite Element Analysis (FEA) was compared to theoretical results for a given design. The results led to a graphical design method which assists the selection of flexure bearing geometrical parameters based on pre-determined geometric and material constraints.

  14. XML-based product information processing method for product design

    NASA Astrophysics Data System (ADS)

    Zhang, Zhen Yu

    2012-01-01

    Design knowledge of modern mechatronics product is based on information processing as the center of the knowledge-intensive engineering, thus product design innovation is essentially the knowledge and information processing innovation. Analysis of the role of mechatronics product design knowledge and information management features, a unified model of XML-based product information processing method is proposed. Information processing model of product design includes functional knowledge, structural knowledge and their relationships. For the expression of product function element, product structure element, product mapping relationship between function and structure based on the XML model are proposed. The information processing of a parallel friction roller is given as an example, which demonstrates that this method is obviously helpful for knowledge-based design system and product innovation.

  15. XML-based product information processing method for product design

    NASA Astrophysics Data System (ADS)

    Zhang, Zhen Yu

    2011-12-01

    Design knowledge of modern mechatronics product is based on information processing as the center of the knowledge-intensive engineering, thus product design innovation is essentially the knowledge and information processing innovation. Analysis of the role of mechatronics product design knowledge and information management features, a unified model of XML-based product information processing method is proposed. Information processing model of product design includes functional knowledge, structural knowledge and their relationships. For the expression of product function element, product structure element, product mapping relationship between function and structure based on the XML model are proposed. The information processing of a parallel friction roller is given as an example, which demonstrates that this method is obviously helpful for knowledge-based design system and product innovation.

  16. On design methods for bolted joints in composite aircraft structures

    NASA Astrophysics Data System (ADS)

    Ireman, Tomas; Nyman, Tonny; Hellbom, Kurt

    The problems related to the determination of the load distribution in a multirow fastener joint using the finite element method are discussed. Both simple and more advanced design methods used at Saab Military Aircraft are presented. The stress distributions obtained with an analytically based method and an FE-based method are compared. Results from failure predictions with a simple analytically based method and the more advanced FE-based method of multi-fastener tension and shear loaded test specimens are compared with experiments. Finally, complicating factors such as three-dimensional effects caused by secondary bending and fastener bending are discussed and suggestions for future research are given.

  17. A Bright Future for Evolutionary Methods in Drug Design.

    PubMed

    Le, Tu C; Winkler, David A

    2015-08-01

    Most medicinal chemists understand that chemical space is extremely large, essentially infinite. Although high-throughput experimental methods allow exploration of drug-like space more rapidly, they are still insufficient to fully exploit the opportunities that such large chemical space offers. Evolutionary methods can synergistically blend automated synthesis and characterization methods with computational design to identify promising regions of chemical space more efficiently. We describe how evolutionary methods are implemented, and provide examples of published drug development research in which these methods have generated molecules with increased efficacy. We anticipate that evolutionary methods will play an important role in future drug discovery.

  18. Design of diffractive optical surfaces within the nonimaging SMS design method

    NASA Astrophysics Data System (ADS)

    Mendes-Lopes, João.; Benítez, Pablo; Miñano, Juan C.

    2015-09-01

    The Simultaneous Multiple Surface (SMS) method was initially developed as a design method in Nonimaging Optics and later, the method was extended for designing Imaging Optics. We show an extension of the SMS method to diffractive surfaces. Using this method, diffractive kinoform surfaces are calculated simultaneously and through a direct method, i. e. it is not based in multi-parametric optimization techniques. Using the phase-shift properties of diffractive surfaces as an extra degree of freedom, only N/2 surfaces are needed to perfectly couple N one parameter wavefronts. Wavefronts of different wavelengths can also be coupled, hence chromatic aberration can be corrected in SMS-based systems. This method can be used by combining and calculating simultaneously both reflective, refractive and diffractive surfaces, through direct calculation of phase and refractive/reflective profiles. Representative diffractive systems designed by the SMS method are presented.

  19. Placement and Format of Risk Information on Direct-to-Consumer Prescription Drug Websites.

    PubMed

    Sullivan, Helen W; O'Donoghue, Amie C; Rupert, Douglas J; Willoughby, Jessica Fitts; Aikin, Kathryn J

    2017-02-01

    We investigated whether the location and format of risk information on branded prescription drug websites influence consumers' knowledge and perceptions of the drug's risks. Participants (Internet panelists with high cholesterol [n = 2,609] or seasonal allergies [n = 2,637]) were randomly assigned to view a website promoting a fictitious prescription drug for their condition. The website presented risk information at the bottom of the homepage, or at the bottom of the homepage with a signal above indicating that the risk information was located below, or on a linked secondary page. We also varied the format of risk information (paragraph, checklist, bulleted list, highlighted box). Participants then answered questions on risk recall and perceptions. Participants recalled fewer drug risks when the risks were placed on a secondary page. The signal had little effect, and risk information format did not affect outcomes. The location of risk information on prescription drug websites can affect consumer knowledge of drug risks; however, signals and special formatting may not be necessary for websites to adequately inform consumers about drug risks. We recommend that prescription drug websites maintain risk information on their homepages to achieve "fair balance" as required by the U.S. Food and Drug Administration.

  20. The Design with Intent Method: a design tool for influencing user behaviour.

    PubMed

    Lockton, Dan; Harrison, David; Stanton, Neville A

    2010-05-01

    Using product and system design to influence user behaviour offers potential for improving performance and reducing user error, yet little guidance is available at the concept generation stage for design teams briefed with influencing user behaviour. This article presents the Design with Intent Method, an innovation tool for designers working in this area, illustrated via application to an everyday human-technology interaction problem: reducing the likelihood of a customer leaving his or her card in an automatic teller machine. The example application results in a range of feasible design concepts which are comparable to existing developments in ATM design, demonstrating that the method has potential for development and application as part of a user-centred design process.

  1. INNOVATIVE METHODS FOR THE OPTIMIZATION OF GRAVITY STORM SEWER DESIGN

    EPA Science Inventory

    The purpose of this paper is to describe a new method for optimizing the design of urban storm sewer systems. Previous efforts to optimize gravity sewers have met with limited success because classical optimization methods require that the problem be well behaved, e.g. describ...

  2. Designing, Teaching, and Evaluating Two Complementary Mixed Methods Research Courses

    ERIC Educational Resources Information Center

    Christ, Thomas W.

    2009-01-01

    Teaching mixed methods research is difficult. This longitudinal explanatory study examined how two classes were designed, taught, and evaluated. Curriculum, Research, and Teaching (EDCS-606) and Mixed Methods Research (EDCS-780) used a research proposal generation process to highlight the importance of the purpose, research question and…

  3. INNOVATIVE METHODS FOR THE OPTIMIZATION OF GRAVITY STORM SEWER DESIGN

    EPA Science Inventory

    The purpose of this paper is to describe a new method for optimizing the design of urban storm sewer systems. Previous efforts to optimize gravity sewers have met with limited success because classical optimization methods require that the problem be well behaved, e.g. describ...

  4. Communicating breast cancer risk information to young adult women: A pilot study.

    PubMed

    Bernat, Jennifer K; Hullmann, Stephanie E; Sparks, Glenn G

    2017-01-01

    To examine the effectiveness of a health promotion flyer to increase awareness of breast cancer risk and physical activity as a risk reduction strategy in young adult women. Young adult women (N = 123) viewed one of five health promotion flyers online and then completed measures of perceived breast cancer risk (PR) and perceived informativeness (PI) and a qualitative thought-listing activity. Differences were observed in PI such that the control and low risk/low information messages were significantly less informative than the others. Qualitative analyses revealed two general themes: message content and flyer design. Additional analyses of the flyer design comments revealed four sub-themes: negative thoughts about the image, positive thoughts about the image, misunderstanding breast cancer risk information, and social comparison. Exploratory analyses controlling for message type indicated that image appraisal predicted PI such that those who commented on the image found the flyer to be less informative. Results suggest that the flyer was informative but did not impact young women's breast cancer risk perceptions. Additionally, the image may have distracted young women from the intended message. Evaluating the acceptability of images used in health promotion materials is recommended before testing the effectiveness of the intervention.

  5. Advances in multiparameter optimization methods for de novo drug design.

    PubMed

    Segall, Matthew

    2014-07-01

    A high-quality drug must achieve a balance of physicochemical and absorption, distribution, metabolism and elimination properties, safety and potency against its therapeutic target(s). Multiparameter optimization (MPO) methods guide the simultaneous optimization of multiple factors to quickly target compounds with the highest chance of downstream success. MPO can be combined with 'de novo design' methods to automatically generate and assess a large number of diverse structures and identify strategies to optimize a compound's overall balance of properties. The article provides a review of MPO methods and recent developments in the methods and opinions in the field. It also provides a description of advances in de novo design that improve the relevance of automatically generated compound structures and integrate MPO. Finally, the article provides discussion of a recent case study of the automatic design of ligands to polypharmacological profiles. Recent developments have reduced the generation of chemically infeasible structures and improved the quality of compounds generated by de novo design methods. There are concerns about the ability of simple drug-like properties and ligand efficiency indices to effectively guide the detailed optimization of compounds. De novo design methods cannot identify a perfect compound for synthesis, but it can identify high-quality ideas for detailed consideration by an expert scientist.

  6. Test methods and design allowables for fibrous composites. Volume 2

    NASA Technical Reports Server (NTRS)

    Chamis, Christos C. (Editor)

    1989-01-01

    Topics discussed include extreme/hostile environment testing, establishing design allowables, and property/behavior specific testing. Papers are presented on environmental effects on the high strain rate properties of graphite/epoxy composite, the low-temperature performance of short-fiber reinforced thermoplastics, the abrasive wear behavior of unidirectional and woven graphite fiber/PEEK, test methods for determining design allowables for fiber reinforced composites, and statistical methods for calculating material allowables for MIL-HDBK-17. Attention is also given to a test method to measure the response of composite materials under reversed cyclic loads, a through-the-thickness strength specimen for composites, the use of torsion tubes to measure in-plane shear properties of filament-wound composites, the influlence of test fixture design on the Iosipescu shear test for fiber composite materials, and a method for monitoring in-plane shear modulus in fatigue testing of composites.

  7. Test methods and design allowables for fibrous composites. Volume 2

    NASA Technical Reports Server (NTRS)

    Chamis, Christos C. (Editor)

    1989-01-01

    Topics discussed include extreme/hostile environment testing, establishing design allowables, and property/behavior specific testing. Papers are presented on environmental effects on the high strain rate properties of graphite/epoxy composite, the low-temperature performance of short-fiber reinforced thermoplastics, the abrasive wear behavior of unidirectional and woven graphite fiber/PEEK, test methods for determining design allowables for fiber reinforced composites, and statistical methods for calculating material allowables for MIL-HDBK-17. Attention is also given to a test method to measure the response of composite materials under reversed cyclic loads, a through-the-thickness strength specimen for composites, the use of torsion tubes to measure in-plane shear properties of filament-wound composites, the influlence of test fixture design on the Iosipescu shear test for fiber composite materials, and a method for monitoring in-plane shear modulus in fatigue testing of composites.

  8. Comparison of Optimal Design Methods in Inverse Problems

    PubMed Central

    Banks, H. T.; Holm, Kathleen; Kappel, Franz

    2011-01-01

    Typical optimal design methods for inverse or parameter estimation problems are designed to choose optimal sampling distributions through minimization of a specific cost function related to the resulting error in parameter estimates. It is hoped that the inverse problem will produce parameter estimates with increased accuracy using data collected according to the optimal sampling distribution. Here we formulate the classical optimal design problem in the context of general optimization problems over distributions of sampling times. We present a new Prohorov metric based theoretical framework that permits one to treat succinctly and rigorously any optimal design criteria based on the Fisher Information Matrix (FIM). A fundamental approximation theory is also included in this framework. A new optimal design, SE-optimal design (standard error optimal design), is then introduced in the context of this framework. We compare this new design criteria with the more traditional D-optimal and E-optimal designs. The optimal sampling distributions from each design are used to compute and compare standard errors; the standard errors for parameters are computed using asymptotic theory or bootstrapping and the optimal mesh. We use three examples to illustrate ideas: the Verhulst-Pearl logistic population model [13], the standard harmonic oscillator model [13] and a popular glucose regulation model [16, 19, 29]. PMID:21857762

  9. Tradeoff methods in multiobjective insensitive design of airplane control systems

    NASA Technical Reports Server (NTRS)

    Schy, A. A.; Giesy, D. P.

    1984-01-01

    The latest results of an ongoing study of computer-aided design of airplane control systems are given. Constrained minimization algorithms are used, with the design objectives in the constraint vector. The concept of Pareto optimiality is briefly reviewed. It is shown how an experienced designer can use it to find designs which are well-balanced in all objectives. Then the problem of finding designs which are insensitive to uncertainty in system parameters are discussed, introducing a probabilistic vector definition of sensitivity which is consistent with the deterministic Pareto optimal problem. Insensitivity is important in any practical design, but it is particularly important in the design of feedback control systems, since it is considered to be the most important distinctive property of feedback control. Methods of tradeoff between deterministic and stochastic-insensitive (SI) design are described, and tradeoff design results are presented for the example of the a Shuttle lateral stability augmentation system. This example is used because careful studies have been made of the uncertainty in Shuttle aerodynamics. Finally, since accurate statistics of uncertain parameters are usually not available, the effects of crude statistical models on SI designs are examined.

  10. Comparison of Optimal Design Methods in Inverse Problems.

    PubMed

    Banks, H T; Holm, Kathleen; Kappel, Franz

    2011-07-01

    Typical optimal design methods for inverse or parameter estimation problems are designed to choose optimal sampling distributions through minimization of a specific cost function related to the resulting error in parameter estimates. It is hoped that the inverse problem will produce parameter estimates with increased accuracy using data collected according to the optimal sampling distribution. Here we formulate the classical optimal design problem in the context of general optimization problems over distributions of sampling times. We present a new Prohorov metric based theoretical framework that permits one to treat succinctly and rigorously any optimal design criteria based on the Fisher Information Matrix (FIM). A fundamental approximation theory is also included in this framework. A new optimal design, SE-optimal design (standard error optimal design), is then introduced in the context of this framework. We compare this new design criteria with the more traditional D-optimal and E-optimal designs. The optimal sampling distributions from each design are used to compute and compare standard errors; the standard errors for parameters are computed using asymptotic theory or bootstrapping and the optimal mesh. We use three examples to illustrate ideas: the Verhulst-Pearl logistic population model [13], the standard harmonic oscillator model [13] and a popular glucose regulation model [16, 19, 29].

  11. Perspectives toward the stereotype production method for public symbol design: a case study of novice designers.

    PubMed

    Ng, Annie W Y; Siu, Kin Wai Michael; Chan, Chetwyn C H

    2013-01-01

    This study investigated the practices and attitudes of novice designers toward user involvement in public symbol design at the conceptual design stage, i.e. the stereotype production method. Differences between male and female novice designers were examined. Forty-eight novice designers (24 male, 24 female) were asked to design public symbol referents based on suggestions made by a group of users in a previous study and provide feedback with regard to the design process. The novice designers were receptive to the adoption of user suggestions in the conception of the design, but tended to modify the pictorial representations generated by the users to varying extents. It is also significant that the male and female novice designers appeared to emphasize different aspects of user suggestions, and the female novice designers were more positive toward these suggestions than their male counterparts. The findings should aid the optimization of the stereotype production method for user-involved symbol design. Copyright © 2012 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  12. Quantifying Safety Margin Using the Risk-Informed Safety Margin Characterization (RISMC)

    SciTech Connect

    Grabaskas, David; Bucknor, Matthew; Brunett, Acacia; Nakayama, Marvin

    2015-04-26

    The Risk-Informed Safety Margin Characterization (RISMC), developed by Idaho National Laboratory as part of the Light-Water Reactor Sustainability Project, utilizes a probabilistic safety margin comparison between a load and capacity distribution, rather than a deterministic comparison between two values, as is usually done in best-estimate plus uncertainty analyses. The goal is to determine the failure probability, or in other words, the probability of the system load equaling or exceeding the system capacity. While this method has been used in pilot studies, there has been little work conducted investigating the statistical significance of the resulting failure probability. In particular, it is difficult to determine how many simulations are necessary to properly characterize the failure probability. This work uses classical (frequentist) statistics and confidence intervals to examine the impact in statistical accuracy when the number of simulations is varied. Two methods are proposed to establish confidence intervals related to the failure probability established using a RISMC analysis. The confidence interval provides information about the statistical accuracy of the method utilized to explore the uncertainty space, and offers a quantitative method to gauge the increase in statistical accuracy due to performing additional simulations.

  13. Computer method for design of acoustic liners for turbofan engines

    NASA Technical Reports Server (NTRS)

    Minner, G. L.; Rice, E. J.

    1976-01-01

    A design package is presented for the specification of acoustic liners for turbofans. An estimate of the noise generation was made based on modifications of existing noise correlations, for which the inputs are basic fan aerodynamic design variables. The method does not predict multiple pure tones. A target attenuation spectrum was calculated which was the difference between the estimated generation spectrum and a flat annoyance-weighted goal attenuated spectrum. The target spectrum was combined with a knowledge of acoustic liner performance as a function of the liner design variables to specify the acoustic design. The liner design method at present is limited to annular duct configurations. The detailed structure of the liner was specified by combining the required impedance (which is a result of the previous step) with a mathematical model relating impedance to the detailed structure. The design procedure was developed for a liner constructed of perforated sheet placed over honeycomb backing cavities. A sample calculation was carried through in order to demonstrate the design procedure, and experimental results presented show good agreement with the calculated results of the method.

  14. An Integrated Optimization Design Method Based on Surrogate Modeling Applied to Diverging Duct Design

    NASA Astrophysics Data System (ADS)

    Hanan, Lu; Qiushi, Li; Shaobin, Li

    2016-12-01

    This paper presents an integrated optimization design method in which uniform design, response surface methodology and genetic algorithm are used in combination. In detail, uniform design is used to select the experimental sampling points in the experimental domain and the system performance is evaluated by means of computational fluid dynamics to construct a database. After that, response surface methodology is employed to generate a surrogate mathematical model relating the optimization objective and the design variables. Subsequently, genetic algorithm is adopted and applied to the surrogate model to acquire the optimal solution in the case of satisfying some constraints. The method has been applied to the optimization design of an axisymmetric diverging duct, dealing with three design variables including one qualitative variable and two quantitative variables. The method of modeling and optimization design performs well in improving the duct aerodynamic performance and can be also applied to wider fields of mechanical design and seen as a useful tool for engineering designers, by reducing the design time and computation consumption.

  15. Developing Conceptual Hypersonic Airbreathing Engines Using Design of Experiments Methods

    NASA Technical Reports Server (NTRS)

    Ferlemann, Shelly M.; Robinson, Jeffrey S.; Martin, John G.; Leonard, Charles P.; Taylor, Lawrence W.; Kamhawi, Hilmi

    2000-01-01

    Designing a hypersonic vehicle is a complicated process due to the multi-disciplinary synergy that is required. The greatest challenge involves propulsion-airframe integration. In the past, a two-dimensional flowpath was generated based on the engine performance required for a proposed mission. A three-dimensional CAD geometry was produced from the two-dimensional flowpath for aerodynamic analysis, structural design, and packaging. The aerodynamics, engine performance, and mass properties arc inputs to the vehicle performance tool to determine if the mission goals were met. If the mission goals were not met, then a flowpath and vehicle redesign would begin. This design process might have to be performed several times to produce a "closed" vehicle. This paper will describe an attempt to design a hypersonic cruise vehicle propulsion flowpath using a Design of' Experiments method to reduce the resources necessary to produce a conceptual design with fewer iterations of the design cycle. These methods also allow for more flexible mission analysis and incorporation of additional design constraints at any point. A design system was developed using an object-based software package that would quickly generate each flowpath in the study given the values of the geometric independent variables. These flowpath geometries were put into a hypersonic propulsion code and the engine performance was generated. The propulsion results were loaded into statistical software to produce regression equations that were combined with an aerodynamic database to optimize the flowpath at the vehicle performance level. For this example, the design process was executed twice. The first pass was a cursory look at the independent variables selected to determine which variables are the most important and to test all of the inputs to the optimization process. The second cycle is a more in-depth study with more cases and higher order equations representing the design space.

  16. Achieving a Risk-Informed Decision-Making Environment at NASA: The Emphasis of NASA's Risk Management Policy

    NASA Technical Reports Server (NTRS)

    Dezfuli, Homayoon

    2010-01-01

    This slide presentation reviews the evolution of risk management (RM) at NASA. The aim of the RM approach at NASA is to promote an approach that is heuristic, proactive, and coherent across all of NASA. Risk Informed Decision Making (RIDM) is a decision making process that uses a diverse set of performance measures along with other considerations within a deliberative process to inform decision making. RIDM is invoked for key decisions such as architecture and design decisions, make-buy decisions, and budget reallocation. The RIDM process and how it relates to the continuous Risk Management (CRM) process is reviewed.

  17. A New Design Method based on Cooperative Data Mining from Multi-Objective Design Space

    NASA Astrophysics Data System (ADS)

    Sugimura, Kazuyuki; Obayashi, Shigeru; Jeong, Shinkyu

    We propose a new multi-objective parameter design method that uses the combination of the following data mining techniques: analysis of variance, self-organizing map, decision tree analysis, rough set theory, and association rule. This method first aims to improve multiple objective functions simultaneously using as much predominant main effects of different design variables as possible. Then it resolves the remaining conflictions between the objective functions using predominant interaction effects of design variables. The key to realizing this method is the obtaining of various design rules that quantitatively relate levels of design variables to levels of objective functions. Based on comparative studies of data mining techniques, the systematic processes for obtaining these design rules have been clarified, and the points of combining data mining techniques have also been summarized. This method has been applied to a multi-objective robust optimization problem of an industrial fan, and the results show its superior capabilities for controlling parameters to traditional single-objective parameter design methods like the Taguchi method.

  18. A decentralized linear quadratic control design method for flexible structures

    NASA Technical Reports Server (NTRS)

    Su, Tzu-Jeng; Craig, Roy R., Jr.

    1990-01-01

    A decentralized suboptimal linear quadratic control design procedure which combines substructural synthesis, model reduction, decentralized control design, subcontroller synthesis, and controller reduction is proposed for the design of reduced-order controllers for flexible structures. The procedure starts with a definition of the continuum structure to be controlled. An evaluation model of finite dimension is obtained by the finite element method. Then, the finite element model is decomposed into several substructures by using a natural decomposition called substructuring decomposition. Each substructure, at this point, still has too large a dimension and must be reduced to a size that is Riccati-solvable. Model reduction of each substructure can be performed by using any existing model reduction method, e.g., modal truncation, balanced reduction, Krylov model reduction, or mixed-mode method. Then, based on the reduced substructure model, a subcontroller is designed by an LQ optimal control method for each substructure independently. After all subcontrollers are designed, a controller synthesis method called substructural controller synthesis is employed to synthesize all subcontrollers into a global controller. The assembling scheme used is the same as that employed for the structure matrices. Finally, a controller reduction scheme, called the equivalent impulse response energy controller (EIREC) reduction algorithm, is used to reduce the global controller to a reasonable size for implementation. The EIREC reduced controller preserves the impulse response energy of the full-order controller and has the property of matching low-frequency moments and low-frequency power moments. An advantage of the substructural controller synthesis method is that it relieves the computational burden associated with dimensionality. Besides that, the SCS design scheme is also a highly adaptable controller synthesis method for structures with varying configuration, or varying mass

  19. 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.

  20. Approximate Design Method for Single Stage Pulse Tube Refrigerators

    NASA Astrophysics Data System (ADS)

    Pfotenhauer, J. M.; Gan, Z. H.; Radebaugh, R.

    2008-03-01

    An approximate design method is presented for the design of a single stage Stirling type pulse tube refrigerator. The design method begins from a defined cooling power, operating temperature, average and dynamic pressure, and frequency. Using a combination of phasor analysis, approximate correlations derived from extensive use of REGEN3.2, a few `rules of thumb,' and available models for inertance tubes, a process is presented to define appropriate geometries for the regenerator, pulse tube and inertance tube components. In addition, specifications for the acoustic power and phase between the pressure and flow required from the compressor are defined. The process enables an appreciation of the primary physical parameters operating within the pulse tube refrigerator, but relies on approximate values for the combined loss mechanisms. The defined geometries can provide both a useful starting point, and a sanity check, for more sophisticated design methodologies.

  1. A new method named as Segment-Compound method of baffle design

    NASA Astrophysics Data System (ADS)

    Qin, Xing; Yang, Xiaoxu; Gao, Xin; Liu, Xishuang

    2017-02-01

    As the observation demand increased, the demand of the lens imaging quality rising. Segment- Compound baffle design method was proposed in this paper. Three traditional methods of baffle design they are characterized as Inside to Outside, Outside to Inside, and Mirror Symmetry. Through a transmission type of optical system, the four methods were used to design stray light suppression structure for it, respectively. Then, structures modeling simulation with Solidworks, CAXA, Tracepro, At last, point source transmittance (PST) curve lines were got to describe their performance. The result shows that the Segment- Compound method can inhibit stay light more effectively. Moreover, it is easy to active and without use special material.

  2. Rotordynamics and Design Methods of an Oil-Free Turbocharger

    NASA Technical Reports Server (NTRS)

    Howard, Samuel A.

    1999-01-01

    The feasibility of supporting a turbocharger rotor on air foil bearings is investigated based upon predicted rotordynamic stability, load accommodations, and stress considerations. It is demonstrated that foil bearings offer a plausible replacement for oil-lubricated bearings in diesel truck turbochargers. Also, two different rotor configurations are analyzed and the design is chosen which best optimizes the desired performance characteristics. The method of designing machinery for foil bearing use and the assumptions made are discussed.

  3. Methods for Reachability-based Hybrid Controller Design

    DTIC Science & Technology

    2012-05-10

    complexity of systems found in practical applications, the problem of controller design is often approached in a hierarchical fashion , with discrete...is often approached in a hierarchical fashion , with discrete abstractions and design methods used to satisfy high level task specifications, and...0720882 ( CSR - EHS: PRET), #0647591 ( CSR -SGER), and #0720841 ( CSR -CPS)), the U.S. Army Research Of- fice (ARO #W911NF-07-2-0019), U.S. Air Force Office

  4. Mixed methods research design for pragmatic psychoanalytic studies.

    PubMed

    Tillman, Jane G; Clemence, A Jill; Stevens, Jennifer L

    2011-10-01

    Calls for more rigorous psychoanalytic studies have increased over the past decade. The field has been divided by those who assert that psychoanalysis is properly a hermeneutic endeavor and those who see it as a science. A comparable debate is found in research methodology, where qualitative and quantitative methods have often been seen as occupying orthogonal positions. Recently, Mixed Methods Research (MMR) has emerged as a viable "third community" of research, pursuing a pragmatic approach to research endeavors through integrating qualitative and quantitative procedures in a single study design. Mixed Methods Research designs and the terminology associated with this emerging approach are explained, after which the methodology is explored as a potential integrative approach to a psychoanalytic human science. Both qualitative and quantitative research methods are reviewed, as well as how they may be used in Mixed Methods Research to study complex human phenomena.

  5. ERSYS-SPP access method subsystem design specification

    NASA Technical Reports Server (NTRS)

    Weise, R. C. (Principal Investigator)

    1980-01-01

    The STARAN special purpose processor (SPP) is a machine allowing the same operation to be performed on up to 512 different data elements simultaneously. In the ERSYS system, it is to be attached to a 4341 plug compatible machine (PCM) to do certain existing algorithms and, at a later date, to perform other to be specified algorithms. That part of the interface between the 4341 PCM and the SPP located in the 4341 PCM is known as the SPP access method (SPPAM). Access to the SPPAM will be obtained by use of the NQUEUE and DQUEUE commands. The subsystem design specification is to incorporate all applicable design considerations from the ERSYS system design specification and the Level B requirements documents relating to the SPPAM. It is intended as a basis for the preliminary design review and will expand into the subsystem detailed design specification.

  6. Design of large Francis turbine using optimal methods

    NASA Astrophysics Data System (ADS)

    Flores, E.; Bornard, L.; Tomas, L.; Liu, J.; Couston, M.

    2012-11-01

    Among a high number of Francis turbine references all over the world, covering the whole market range of heads, Alstom has especially been involved in the development and equipment of the largest power plants in the world : Three Gorges (China -32×767 MW - 61 to 113 m), Itaipu (Brazil- 20x750 MW - 98.7m to 127m) and Xiangjiaba (China - 8x812 MW - 82.5m to 113.6m - in erection). Many new projects are under study to equip new power plants with Francis turbines in order to answer an increasing demand of renewable energy. In this context, Alstom Hydro is carrying out many developments to answer those needs, especially for jumbo units such the planned 1GW type units in China. The turbine design for such units requires specific care by using the state of the art in computation methods and the latest technologies in model testing as well as the maximum feedback from operation of Jumbo plants already in operation. We present in this paper how a large Francis turbine can be designed using specific design methods, including the global and local optimization methods. The design of the spiral case, the tandem cascade profiles, the runner and the draft tube are designed with optimization loops involving a blade design tool, an automatic meshing software and a Navier-Stokes solver, piloted by a genetic algorithm. These automated optimization methods, presented in different papers over the last decade, are nowadays widely used, thanks to the growing computation capacity of the HPC clusters: the intensive use of such optimization methods at the turbine design stage allows to reach very high level of performances, while the hydraulic flow characteristics are carefully studied over the whole water passage to avoid any unexpected hydraulic phenomena.

  7. Study on Communication System of Social Risk Information on Nuclear Energy

    SciTech Connect

    Hidekazu Yoshikawa; Toshio Sugiman; Yasunaga Wakabayashi; Hiroshi Shimoda; Mika Terado; Mariko Akimoto; Yoshihiko Nagasato

    2004-07-01

    As a new risk communication method for the construction of effective knowledge bases about 'safety and non-anxiety for nuclear energy', a study on new communication method of social risk information by means of electronic communication has been started, by noticing rapid expansion of internet usage in the society. The purpose of this research is to enhance the public acceptance to nuclear power in Japan by the following two aspects. The first is to develop the mutual communication system among the working persons involved in both the operation and maintenance activities for nuclear power plant, by which they will exchange their daily experiences to improve the safety conscious activities to foster 'safety culture' attitude. The other is the development of an effective risk communication system between nuclear society and the general publics about the hot issues of 'what are the concerned involved in the final disposal of high-level radioactive waste?' and 'what should we do to have social consensus to deal with this issue in future'. The authors' research plan for the above purpose is summarized as shown in Table 1. As the first step of the authors' three year research project which started from August 2003, social investigation by questionnaires by internet and postal mail, have been just recently conducted on their risk perception for the nuclear power for the people engaged in nuclear business and women in the metropolitan area, respectively, in order to obtain the relevant information on how and what should be considered for constructing effective risk communication methods of social risk information between the people within nuclear industries and the general public in society. Although there need to be discussed, the contrasting risk images as shown in Fig.1, can be depicted between the nuclear people and general public these days in Japan, from the results of the social investigation. As the conclusion of the authors' study thus far conducted, the

  8. Climate Risk Informed Decision Analysis: A Hypothetical Application to the Waas Region

    NASA Astrophysics Data System (ADS)

    Gilroy, Kristin; Mens, Marjolein; Haasnoot, Marjolijn; Jeuken, Ad

    2016-04-01

    More frequent and intense hydrologic events under climate change are expected to enhance water security and flood risk management challenges worldwide. Traditional planning approaches must be adapted to address climate change and develop solutions with an appropriate level of robustness and flexibility. The Climate Risk Informed Decision Analysis (CRIDA) method is a novel planning approach embodying a suite of complementary methods, including decision scaling and adaptation pathways. Decision scaling offers a bottom-up approach to assess risk and tailors the complexity of the analysis to the problem at hand and the available capacity. Through adaptation pathway,s an array of future strategies towards climate robustness are developed, ranging in flexibility and immediacy of investments. Flexible pathways include transfer points to other strategies to ensure that the system can be adapted if future conditions vary from those expected. CRIDA combines these two approaches in a stakeholder driven process which guides decision makers through the planning and decision process, taking into account how the confidence in the available science, the consequences in the system, and the capacity of institutions should influence strategy selection. In this presentation, we will explain the CRIDA method and compare it to existing planning processes, such as the US Army Corps of Engineers Principles and Guidelines as well as Integrated Water Resources Management Planning. Then, we will apply the approach to a hypothetical case study for the Waas Region, a large downstream river basin facing rapid development threatened by increased flood risks. Through the case study, we will demonstrate how a stakeholder driven process can be used to evaluate system robustness to climate change; develop adaptation pathways for multiple objectives and criteria; and illustrate how varying levels of confidence, consequences, and capacity would play a role in the decision making process, specifically

  9. Computational methods of robust controller design for aerodynamic flutter suppression

    NASA Technical Reports Server (NTRS)

    Anderson, L. R.

    1981-01-01

    The development of Riccati iteration, a tool for the design and analysis of linear control systems is examined. First, Riccati iteration is applied to the problem of pole placement and order reduction in two-time scale control systems. Order reduction, yielding a good approximation to the original system, is demonstrated using a 16th order linear model of a turbofan engine. Next, a numerical method for solving the Riccati equation is presented and demonstrated for a set of eighth order random examples. A literature review of robust controller design methods follows which includes a number of methods for reducing the trajectory and performance index sensitivity in linear regulators. Lastly, robust controller design for large parameter variations is discussed.

  10. Improved method for transonic airfoil design-by-optimization

    NASA Technical Reports Server (NTRS)

    Kennelly, R. A., Jr.

    1983-01-01

    An improved method for use of optimization techniques in transonic airfoil design is demonstrated. FLO6QNM incorporates a modified quasi-Newton optimization package, and is shown to be more reliable and efficient than the method developed previously at NASA-Ames, which used the COPES/CONMIN optimization program. The design codes are compared on a series of test cases with known solutions, and the effects of problem scaling, proximity of initial point to solution, and objective function precision are studied. In contrast to the older method, well-converged solutions are shown to be attainable in the context of engineering design using computational fluid dynamics tools, a new result. The improvements are due to better performance by the optimization routine and to the use of problem-adaptive finite difference step sizes for gradient evaluation.

  11. Design of an explosive detection system using Monte Carlo method.

    PubMed

    Hernández-Adame, Pablo Luis; Medina-Castro, Diego; Rodriguez-Ibarra, Johanna Lizbeth; Salas-Luevano, Miguel Angel; Vega-Carrillo, Hector Rene

    2016-11-01

    Regardless the motivation terrorism is the most important risk for the national security in many countries. Attacks with explosives are the most common method used by terrorists. Therefore several procedures to detect explosives are utilized; among these methods are the use of neutrons and photons. In this study the Monte Carlo method an explosive detection system using a (241)AmBe neutron source was designed. In the design light water, paraffin, polyethylene, and graphite were used as moderators. In the work the explosive RDX was used and the induced gamma rays due to neutron capture in the explosive was estimated using NaI(Tl) and HPGe detectors. When light water is used as moderator and HPGe as the detector the system has the best performance allowing distinguishing between the explosive and urea. For the final design the Ambient dose equivalent for neutrons and photons were estimated along the radial and axial axis.

  12. 75 FR 25239 - Integrated Risk Information System (IRIS); Announcement of Availability of Literature Searches...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-07

    ... invited to review the literature search results and submit additional information to EPA. Literature... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY Integrated Risk Information System (IRIS); Announcement of Availability of Literature Searches for...

  13. A Tutorial on Probablilistic Risk Assessement and its Role in Risk-Informed Decision Making

    NASA Technical Reports Server (NTRS)

    Dezfuli, Homayoon

    2010-01-01

    This slide presentation reviews risk assessment and its role in risk-informed decision making. It includes information on probabilistic risk assessment, typical risk management process, origins of risk matrix, performance measures, performance objectives and Bayes theorem.

  14. EVALUATING INTERNAL STAKEHOLDER PERSPECTIVES ON RISK-INFORMED REGULATORY PRACTICES FOR THE NUCLEAR REGULATORY COMMISSION

    SciTech Connect

    Peterson, L.K.; Wight, E.H.; Caruso, M.A.

    2003-02-27

    The U.S. Nuclear Regulatory Commission's (NRC) Office of Nuclear Reactor Regulation has begun a program to create a risk-informed environment within the reactor program. The first step of the process is to evaluate the existing environment and internal NRC stakeholder perceptions of risk-informed regulatory practices. This paper reports on the results of the first phase of this evaluation: assessing the current environment, including the level of acceptance of risk-informed approaches throughout the reactor program, the level of integration, areas of success, and areas of difficulty. The other two phases of the evaluation will identify barriers to the integration of risk into NRC activities and gather input on how to move to a risk-informed environment.

  15. A method for the probabilistic design assessment of composite structures

    NASA Technical Reports Server (NTRS)

    Shiao, Michael C.; Singhal, Surendra N.; Chamis, Christos C.

    1994-01-01

    A formal procedure for the probabilistic design assessment of a composite structure is described. The uncertainties in all aspects of a composite structure (constituent material properties, fabrication variables, structural geometry, service environments, etc.), which result in the uncertain behavior in the composite structural responses, are included in the assessment. The probabilistic assessment consists of design criteria, modeling of composite structures and uncertainties, simulation methods, and the decision making process. A sample case is presented to illustrate the formal procedure and to demonstrate that composite structural designs can be probabilistically assessed with accuracy and efficiency.

  16. Inverse design of airfoils using a flexible membrane method

    NASA Astrophysics Data System (ADS)

    Thinsurat, Kamon

    The Modified Garabedian Mc-Fadden (MGM) method is used to inversely design airfoils. The Finite Difference Method (FDM) for Non-Uniform Grids was developed to discretize the MGM equation for numerical solving. The Finite Difference Method (FDM) for Non-Uniform Grids has the advantage of being used flexibly with an unstructured grids airfoil. The commercial software FLUENT is being used as the flow solver. Several conditions are set in FLUENT such as subsonic inviscid flow, subsonic viscous flow, transonic inviscid flow, and transonic viscous flow to test the inverse design code for each condition. A moving grid program is used to create a mesh for new airfoils prior to importing meshes into FLUENT for the analysis of flows. For validation, an iterative process is used so the Cp distribution of the initial airfoil, the NACA0011, achieves the Cp distribution of the target airfoil, the NACA2315, for the subsonic inviscid case at M=0.2. Three other cases were carried out to validate the code. After the code validations, the inverse design method was used to design a shock free airfoil in the transonic condition and to design a separation free airfoil at a high angle of attack in the subsonic condition.

  17. An uncertain multidisciplinary design optimization method using interval convex models

    NASA Astrophysics Data System (ADS)

    Li, Fangyi; Luo, Zhen; Sun, Guangyong; Zhang, Nong

    2013-06-01

    This article proposes an uncertain multi-objective multidisciplinary design optimization methodology, which employs the interval model to represent the uncertainties of uncertain-but-bounded parameters. The interval number programming method is applied to transform each uncertain objective function into two deterministic objective functions, and a satisfaction degree of intervals is used to convert both the uncertain inequality and equality constraints to deterministic inequality constraints. In doing so, an unconstrained deterministic optimization problem will be constructed in association with the penalty function method. The design will be finally formulated as a nested three-loop optimization, a class of highly challenging problems in the area of engineering design optimization. An advanced hierarchical optimization scheme is developed to solve the proposed optimization problem based on the multidisciplinary feasible strategy, which is a well-studied method able to reduce the dimensions of multidisciplinary design optimization problems by using the design variables as independent optimization variables. In the hierarchical optimization system, the non-dominated sorting genetic algorithm II, sequential quadratic programming method and Gauss-Seidel iterative approach are applied to the outer, middle and inner loops of the optimization problem, respectively. Typical numerical examples are used to demonstrate the effectiveness of the proposed methodology.

  18. Breaking from binaries - using a sequential mixed methods design.

    PubMed

    Larkin, Patricia Mary; Begley, Cecily Marion; Devane, Declan

    2014-03-01

    To outline the traditional worldviews of healthcare research and discuss the benefits and challenges of using mixed methods approaches in contributing to the development of nursing and midwifery knowledge. There has been much debate about the contribution of mixed methods research to nursing and midwifery knowledge in recent years. A sequential exploratory design is used as an exemplar of a mixed methods approach. The study discussed used a combination of focus-group interviews and a quantitative instrument to obtain a fuller understanding of women's experiences of childbirth. In the mixed methods study example, qualitative data were analysed using thematic analysis and quantitative data using regression analysis. Polarised debates about the veracity, philosophical integrity and motivation for conducting mixed methods research have largely abated. A mixed methods approach can contribute to a deeper, more contextual understanding of a variety of subjects and experiences; as a result, it furthers knowledge that can be used in clinical practice. The purpose of the research study should be the main instigator when choosing from an array of mixed methods research designs. Mixed methods research offers a variety of models that can augment investigative capabilities and provide richer data than can a discrete method alone. This paper offers an example of an exploratory, sequential approach to investigating women's childbirth experiences. A clear framework for the conduct and integration of the different phases of the mixed methods research process is provided. This approach can be used by practitioners and policy makers to improve practice.

  19. Evaluation of Methods for Multidisciplinary Design Optimization (MDO). Phase 1

    NASA Technical Reports Server (NTRS)

    Kodiyalam, Srinivas

    1998-01-01

    The NASA Langley Multidisciplinary Design Optimization (MDO) method evaluation study seeks to arrive at a set of guidelines for using promising MDO methods by accumulating and analyzing computational data for such methods. The data are collected by conducting a series of reproducible experiments. This report documents all computational experiments conducted in Phase I of the study. This report is a companion to the paper titled Initial Results of an MDO Method Evaluation Study by N. M. Alexandrov and S. Kodiyalam (AIAA-98-4884).

  20. Exploration of Advanced Probabilistic and Stochastic Design Methods

    NASA Technical Reports Server (NTRS)

    Mavris, Dimitri N.

    2003-01-01

    The primary objective of the three year research effort was to explore advanced, non-deterministic aerospace system design methods that may have relevance to designers and analysts. The research pursued emerging areas in design methodology and leverage current fundamental research in the area of design decision-making, probabilistic modeling, and optimization. The specific focus of the three year investigation was oriented toward methods to identify and analyze emerging aircraft technologies in a consistent and complete manner, and to explore means to make optimal decisions based on this knowledge in a probabilistic environment. The research efforts were classified into two main areas. First, Task A of the grant has had the objective of conducting research into the relative merits of possible approaches that account for both multiple criteria and uncertainty in design decision-making. In particular, in the final year of research, the focus was on the comparison and contrasting between three methods researched. Specifically, these three are the Joint Probabilistic Decision-Making (JPDM) technique, Physical Programming, and Dempster-Shafer (D-S) theory. The next element of the research, as contained in Task B, was focused upon exploration of the Technology Identification, Evaluation, and Selection (TIES) methodology developed at ASDL, especially with regards to identification of research needs in the baseline method through implementation exercises. The end result of Task B was the documentation of the evolution of the method with time and a technology transfer to the sponsor regarding the method, such that an initial capability for execution could be obtained by the sponsor. Specifically, the results of year 3 efforts were the creation of a detailed tutorial for implementing the TIES method. Within the tutorial package, templates and detailed examples were created for learning and understanding the details of each step. For both research tasks, sample files and

  1. Review of SMS design methods and real-world applications

    NASA Astrophysics Data System (ADS)

    Dross, Oliver; Mohedano, Ruben; Benitez, Pablo; Minano, Juan Carlos; Chaves, Julio; Blen, Jose; Hernandez, Maikel; Munoz, Fernando

    2004-09-01

    The Simultaneous Multiple Surfaces design method (SMS), proprietary technology of Light Prescription Innovators (LPI), was developed in the early 1990's as a two dimensional method. The first embodiments had either linear or rotational symmetry and found applications in photovoltaic concentrators, illumination optics and optical communications. SMS designed devices perform close to the thermodynamic limit and are compact and simple; features that are especially beneficial in applications with today's high brightness LEDs. The method was extended to 3D "free form" geometries in 1999 that perfectly couple two incoming with two outgoing wavefronts. SMS 3D controls the light emitted by an extended light source much better than single free form surface designs, while reaching very high efficiencies. This has enabled the SMS method to be applied to automotive head lamps, one of the toughest lighting tasks in any application, where high efficiency and small size are required. This article will briefly review the characteristics of both the 2D and 3D methods and will present novel optical solutions that have been developed and manufactured to meet real world problems. These include various ultra compact LED collimators, solar concentrators and highly efficient LED low and high beam headlamp designs.

  2. A PDE Sensitivity Equation Method for Optimal Aerodynamic Design

    NASA Technical Reports Server (NTRS)

    Borggaard, Jeff; Burns, John

    1996-01-01

    The use of gradient based optimization algorithms in inverse design is well established as a practical approach to aerodynamic design. A typical procedure uses a simulation scheme to evaluate the objective function (from the approximate states) and its gradient, then passes this information to an optimization algorithm. Once the simulation scheme (CFD flow solver) has been selected and used to provide approximate function evaluations, there are several possible approaches to the problem of computing gradients. One popular method is to differentiate the simulation scheme and compute design sensitivities that are then used to obtain gradients. Although this black-box approach has many advantages in shape optimization problems, one must compute mesh sensitivities in order to compute the design sensitivity. In this paper, we present an alternative approach using the PDE sensitivity equation to develop algorithms for computing gradients. This approach has the advantage that mesh sensitivities need not be computed. Moreover, when it is possible to use the CFD scheme for both the forward problem and the sensitivity equation, then there are computational advantages. An apparent disadvantage of this approach is that it does not always produce consistent derivatives. However, for a proper combination of discretization schemes, one can show asymptotic consistency under mesh refinement, which is often sufficient to guarantee convergence of the optimal design algorithm. In particular, we show that when asymptotically consistent schemes are combined with a trust-region optimization algorithm, the resulting optimal design method converges. We denote this approach as the sensitivity equation method. The sensitivity equation method is presented, convergence results are given and the approach is illustrated on two optimal design problems involving shocks.

  3. Defining a risk-informed framework for whole-of-government lessons learned: A Canadian perspective.

    PubMed

    Friesen, Shaye K; Kelsey, Shelley; Legere, J A Jim

    Lessons learned play an important role in emergency management (EM) and organizational agility. Virtually all aspects of EM can derive benefit from a lessons learned program. From major security events to exercises, exploiting and applying lessons learned and "best practices" is critical to organizational resilience and adaptiveness. A robust lessons learned process and methodology provides an evidence base with which to inform decisions, guide plans, strengthen mitigation strategies, and assist in developing tools for operations. The Canadian Safety and Security Program recently supported a project to define a comprehensive framework that would allow public safety and security partners to regularly share event response best practices, and prioritize recommendations originating from after action reviews. This framework consists of several inter-locking elements: a comprehensive literature review/environmental scan of international programs; a survey to collect data from end users and management; the development of a taxonomy for organizing and structuring information; a risk-informed methodology for selecting, prioritizing, and following through on recommendations; and standardized templates and tools for tracking recommendations and ensuring implementation. This article discusses the efforts of the project team, which provided "best practice" advice and analytical support to ensure that a systematic approach to lessons learned was taken by the federal community to improve prevention, preparedness, and response activities. It posits an approach by which one might design a systematic process for information sharing and event response coordination-an approach that will assist federal departments to institutionalize a cross-government lessons learned program.

  4. Risk informed resource allocation policy: safety can save costs.

    PubMed

    Pasman, H J

    2000-01-07

    During economic doldrums, decision making on investments for safety is even more difficult than it already is when funds are abundant. This paper attempts to offer some guidance. After stating the present challenge to prevention of losses in the process industries, the systematic approach of quantified risk assessment is briefly reviewed and improvements in the methodology are mentioned. In addition, attention is given to the use of a risk matrix to survey a plant and to derive a plan of action. Subsequently, the reduction of risk is reviewed. Measures for prevention, protection, and mitigation are discussed. The organization of safety has become at least as important as technical safety of equipment and standards. It is reflected in the introduction of a safety management system. Furthermore, the design process in a pro-active approach is described and the concept of inherent safety is briefly addressed. The concept of Layer of Protection Analysis is explained and also the reason why it is relevant to provide a cost-benefit analysis. Finally, after comments regarding the cost of accidents, the basics of costing and profitability are summarized and a way is suggested to apply this approach to risk-reducing measures. An example is provided on how a selection can be made from a number of alternatives.

  5. Taguchi method of experimental design in materials education

    NASA Technical Reports Server (NTRS)

    Weiser, Martin W.

    1993-01-01

    Some of the advantages and disadvantages of the Taguchi Method of experimental design as applied to Materials Science will be discussed. This is a fractional factorial method that employs the minimum number of experimental trials for the information obtained. The analysis is also very simple to use and teach, which is quite advantageous in the classroom. In addition, the Taguchi loss function can be easily incorporated to emphasize that improvements in reproducibility are often at least as important as optimization of the response. The disadvantages of the Taguchi Method include the fact that factor interactions are normally not accounted for, there are zero degrees of freedom if all of the possible factors are used, and randomization is normally not used to prevent environmental biasing. In spite of these disadvantages it is felt that the Taguchi Method is extremely useful for both teaching experimental design and as a research tool, as will be shown with a number of brief examples.

  6. Taguchi method of experimental design in materials education

    NASA Technical Reports Server (NTRS)

    Weiser, Martin W.

    1993-01-01

    Some of the advantages and disadvantages of the Taguchi Method of experimental design as applied to Materials Science will be discussed. This is a fractional factorial method that employs the minimum number of experimental trials for the information obtained. The analysis is also very simple to use and teach, which is quite advantageous in the classroom. In addition, the Taguchi loss function can be easily incorporated to emphasize that improvements in reproducibility are often at least as important as optimization of the response. The disadvantages of the Taguchi Method include the fact that factor interactions are normally not accounted for, there are zero degrees of freedom if all of the possible factors are used, and randomization is normally not used to prevent environmental biasing. In spite of these disadvantages it is felt that the Taguchi Method is extremely useful for both teaching experimental design and as a research tool, as will be shown with a number of brief examples.

  7. Molecular library design using multi-objective optimization methods.

    PubMed

    Nicolaou, Christos A; Kannas, Christos C

    2011-01-01

    Advancements in combinatorial chemistry and high-throughput screening technology have enabled the synthesis and screening of large molecular libraries for the purposes of drug discovery. Contrary to initial expectations, the increase in screening library size, typically combined with an emphasis on compound structural diversity, did not result in a comparable increase in the number of promising hits found. In an effort to improve the likelihood of discovering hits with greater optimization potential, more recent approaches attempt to incorporate additional knowledge to the library design process to effectively guide the search. Multi-objective optimization methods capable of taking into account several chemical and biological criteria have been used to design collections of compounds satisfying simultaneously multiple pharmaceutically relevant objectives. In this chapter, we present our efforts to implement a multi-objective optimization method, MEGALib, custom-designed to the library design problem. The method exploits existing knowledge, e.g. from previous biological screening experiments, to identify and profile molecular fragments used subsequently to design compounds compromising the various objectives.

  8. Function combined method for design innovation of children's bike

    NASA Astrophysics Data System (ADS)

    Wu, Xiaoli; Qiu, Tingting; Chen, Huijuan

    2013-03-01

    As children mature, bike products for children in the market develop at the same time, and the conditions are frequently updated. Certain problems occur when using a bike, such as cycle overlapping, repeating function, and short life cycle, which go against the principles of energy conservation and the environmental protection intensive design concept. In this paper, a rational multi-function method of design through functional superposition, transformation, and technical implementation is proposed. An organic combination of frog-style scooter and children's tricycle is developed using the multi-function method. From the ergonomic perspective, the paper elaborates on the body size of children aged 5 to 12 and effectively extracts data for a multi-function children's bike, which can be used for gliding and riding. By inverting the body, parts can be interchanged between the handles and the pedals of the bike. Finally, the paper provides a detailed analysis of the components and structural design, body material, and processing technology of the bike. The study of Industrial Product Innovation Design provides an effective design method to solve the bicycle problems, extends the function problems, improves the product market situation, and enhances the energy saving feature while implementing intensive product development effectively at the same time.

  9. A Simple Method for High-Lift Propeller Conceptual Design

    NASA Technical Reports Server (NTRS)

    Patterson, Michael; Borer, Nick; German, Brian

    2016-01-01

    In this paper, we present a simple method for designing propellers that are placed upstream of the leading edge of a wing in order to augment lift. Because the primary purpose of these "high-lift propellers" is to increase lift rather than produce thrust, these props are best viewed as a form of high-lift device; consequently, they should be designed differently than traditional propellers. We present a theory that describes how these props can be designed to provide a relatively uniform axial velocity increase, which is hypothesized to be advantageous for lift augmentation based on a literature survey. Computational modeling indicates that such propellers can generate the same average induced axial velocity while consuming less power and producing less thrust than conventional propeller designs. For an example problem based on specifications for NASA's Scalable Convergent Electric Propulsion Technology and Operations Research (SCEPTOR) flight demonstrator, a propeller designed with the new method requires approximately 15% less power and produces approximately 11% less thrust than one designed for minimum induced loss. Higher-order modeling and/or wind tunnel testing are needed to verify the predicted performance.

  10. System Synthesis in Preliminary Aircraft Design using Statistical Methods

    NASA Technical Reports Server (NTRS)

    DeLaurentis, Daniel; Mavris, Dimitri N.; Schrage, Daniel P.

    1996-01-01

    This paper documents an approach to conceptual and preliminary aircraft design in which system synthesis is achieved using statistical methods, specifically design of experiments (DOE) and response surface methodology (RSM). These methods are employed in order to more efficiently search the design space for optimum configurations. In particular, a methodology incorporating three uses of these techniques is presented. First, response surface equations are formed which represent aerodynamic analyses, in the form of regression polynomials, which are more sophisticated than generally available in early design stages. Next, a regression equation for an overall evaluation criterion is constructed for the purpose of constrained optimization at the system level. This optimization, though achieved in a innovative way, is still traditional in that it is a point design solution. The methodology put forward here remedies this by introducing uncertainty into the problem, resulting a solutions which are probabilistic in nature. DOE/RSM is used for the third time in this setting. The process is demonstrated through a detailed aero-propulsion optimization of a high speed civil transport. Fundamental goals of the methodology, then, are to introduce higher fidelity disciplinary analyses to the conceptual aircraft synthesis and provide a roadmap for transitioning from point solutions to probabalistic designs (and eventually robust ones).

  11. An interdisciplinary heuristic evaluation method for universal building design.

    PubMed

    Afacan, Yasemin; Erbug, Cigdem

    2009-07-01

    This study highlights how heuristic evaluation as a usability evaluation method can feed into current building design practice to conform to universal design principles. It provides a definition of universal usability that is applicable to an architectural design context. It takes the seven universal design principles as a set of heuristics and applies an iterative sequence of heuristic evaluation in a shopping mall, aiming to achieve a cost-effective evaluation process. The evaluation was composed of three consecutive sessions. First, five evaluators from different professions were interviewed regarding the construction drawings in terms of universal design principles. Then, each evaluator was asked to perform the predefined task scenarios. In subsequent interviews, the evaluators were asked to re-analyze the construction drawings. The results showed that heuristic evaluation could successfully integrate universal usability into current building design practice in two ways: (i) it promoted an iterative evaluation process combined with multi-sessions rather than relying on one evaluator and on one evaluation session to find the maximum number of usability problems, and (ii) it highlighted the necessity of an interdisciplinary ad hoc committee regarding the heuristic abilities of each profession. A multi-session and interdisciplinary heuristic evaluation method can save both the project budget and the required time, while ensuring a reduced error rate for the universal usage of the built environments.

  12. Comparison of optimal design methods in inverse problems

    NASA Astrophysics Data System (ADS)

    Banks, H. T.; Holm, K.; Kappel, F.

    2011-07-01

    Typical optimal design methods for inverse or parameter estimation problems are designed to choose optimal sampling distributions through minimization of a specific cost function related to the resulting error in parameter estimates. It is hoped that the inverse problem will produce parameter estimates with increased accuracy using data collected according to the optimal sampling distribution. Here we formulate the classical optimal design problem in the context of general optimization problems over distributions of sampling times. We present a new Prohorov metric-based theoretical framework that permits one to treat succinctly and rigorously any optimal design criteria based on the Fisher information matrix. A fundamental approximation theory is also included in this framework. A new optimal design, SE-optimal design (standard error optimal design), is then introduced in the context of this framework. We compare this new design criterion with the more traditional D-optimal and E-optimal designs. The optimal sampling distributions from each design are used to compute and compare standard errors; the standard errors for parameters are computed using asymptotic theory or bootstrapping and the optimal mesh. We use three examples to illustrate ideas: the Verhulst-Pearl logistic population model (Banks H T and Tran H T 2009 Mathematical and Experimental Modeling of Physical and Biological Processes (Boca Raton, FL: Chapman and Hall/CRC)), the standard harmonic oscillator model (Banks H T and Tran H T 2009) and a popular glucose regulation model (Bergman R N, Ider Y Z, Bowden C R and Cobelli C 1979 Am. J. Physiol. 236 E667-77 De Gaetano A and Arino O 2000 J. Math. Biol. 40 136-68 Toffolo G, Bergman R N, Finegood D T, Bowden C R and Cobelli C 1980 Diabetes 29 979-90).

  13. New Methods and Transducer Designs for Ultrasonic Diagnostics and Therapy

    NASA Astrophysics Data System (ADS)

    Rybyanets, A. N.; Naumenko, A. A.; Sapozhnikov, O. A.; Khokhlova, V. A.

    Recent advances in the field of physical acoustics, imaging technologies, piezoelectric materials, and ultrasonic transducer design have led to emerging of novel methods and apparatus for ultrasonic diagnostics, therapy and body aesthetics. The paper presents the results on development and experimental study of different high intensity focused ultrasound (HIFU) transducers. Technological peculiarities of the HIFU transducer design as well as theoretical and numerical models of such transducers and the corresponding HIFU fields are discussed. Several HIFU transducers of different design have been fabricated using different advanced piezoelectric materials. Acoustic field measurements for those transducers have been performed using a calibrated fiber optic hydrophone and an ultrasonic measurement system (UMS). The results of ex vivo experiments with different tissues as well as in vivo experiments with blood vessels are presented that prove the efficacy, safety and selectivity of the developed HIFU transducers and methods.

  14. New displacement-based methods for optimal truss topology design

    NASA Technical Reports Server (NTRS)

    Bendsoe, Martin P.; Ben-Tal, Aharon; Haftka, Raphael T.

    1991-01-01

    Two alternate methods for maximum stiffness truss topology design are presented. The ground structure approach is used, and the problem is formulated in terms of displacements and bar areas. This large, nonconvex optimization problem can be solved by a simultaneous analysis and design approach. Alternatively, an equivalent, unconstrained, and convex problem in the displacements only can be formulated, and this problem can be solved by a nonsmooth, steepest descent algorithm. In both methods, the explicit solving of the equilibrium equations and the assembly of the global stiffness matrix are circumvented. A large number of examples have been studied, showing the attractive features of topology design as well as exposing interesting features of optimal topologies.

  15. Multi-objective optimization methods in drug design.

    PubMed

    Nicolaou, Christos A; Brown, Nathan

    2013-09-01

    Drug discovery is a challenging multi-objective problem where numerous pharmaceutically important objectives need to be adequately satisfied for a solution to be found. The problem is characterized by vast, complex solution spaces further perplexed by the presence of conflicting objectives. Multi-objective optimization methods, designed specifically to address such problems, have been introduced to the drug discovery field over a decade ago and have steadily gained in acceptance ever since. This paper reviews the latest multi-objective methods and applications reported in the literature, specifically in quantitative structure–activity modeling, docking, de novo design and library design. Further, the paper reports on related developments in drug discovery research and advances in the multi-objective optimization field.

  16. Continuation methods in multiobjective optimization for combined structure control design

    NASA Technical Reports Server (NTRS)

    Milman, M.; Salama, M.; Scheid, R.; Bruno, R.; Gibson, J. S.

    1990-01-01

    A homotopy approach involving multiobjective functions is developed to outline the methods that have evolved for the combined control-structure optimization of physical systems encountered in the technology of large space structures. A method to effect a timely consideration of the control performance prior to the finalization of the structural design involves integrating the control and structural design processes into a unified design methodology that combines the two optimization problems into a single formulation. This study uses the combined optimization problem as a family of weighted structural and control costs. Connections with vector optimizations are described; an analysis of the zero-set of required conditions is made, and a numerical example is given.

  17. Designs and Methods in School Improvement Research: A Systematic Review

    ERIC Educational Resources Information Center

    Feldhoff, Tobias; Radisch, Falk; Bischof, Linda Marie

    2016-01-01

    Purpose: The purpose of this paper is to focus on challenges faced by longitudinal quantitative analyses of school improvement processes and offers a systematic literature review of current papers that use longitudinal analyses. In this context, the authors assessed designs and methods that are used to analyze the relation between school…

  18. Impact design methods for ceramic components in gas turbine engines

    NASA Technical Reports Server (NTRS)

    Song, J.; Cuccio, J.; Kington, H.

    1991-01-01

    Methods currently under development to design ceramic turbine components with improved impact resistance are presented. Two different modes of impact damage are identified and characterized, i.e., structural damage and local damage. The entire computation is incorporated into the EPIC computer code. Model capability is demonstrated by simulating instrumented plate impact and particle impact tests.

  19. Impact design methods for ceramic components in gas turbine engines

    NASA Technical Reports Server (NTRS)

    Song, J.; Cuccio, J.; Kington, H.

    1991-01-01

    Methods currently under development to design ceramic turbine components with improved impact resistance are presented. Two different modes of impact damage are identified and characterized, i.e., structural damage and local damage. The entire computation is incorporated into the EPIC computer code. Model capability is demonstrated by simulating instrumented plate impact and particle impact tests.

  20. Using Propensity Score Methods to Approximate Factorial Experimental Designs

    ERIC Educational Resources Information Center

    Dong, Nianbo

    2011-01-01

    The purpose of this study is through Monte Carlo simulation to compare several propensity score methods in approximating factorial experimental design and identify best approaches in reducing bias and mean square error of parameter estimates of the main and interaction effects of two factors. Previous studies focused more on unbiased estimates of…

  1. Designs and Methods in School Improvement Research: A Systematic Review

    ERIC Educational Resources Information Center

    Feldhoff, Tobias; Radisch, Falk; Bischof, Linda Marie

    2016-01-01

    Purpose: The purpose of this paper is to focus on challenges faced by longitudinal quantitative analyses of school improvement processes and offers a systematic literature review of current papers that use longitudinal analyses. In this context, the authors assessed designs and methods that are used to analyze the relation between school…

  2. Obtaining Valid Response Rates: Considerations beyond the Tailored Design Method.

    ERIC Educational Resources Information Center

    Huang, Judy Y.; Hubbard, Susan M.; Mulvey, Kevin P.

    2003-01-01

    Reports on the use of the tailored design method (TDM) to achieve high survey response in two separate studies of the dissemination of Treatment Improvement Protocols (TIPs). Findings from these two studies identify six factors may have influenced nonresponse, and show that use of TDM does not, in itself, guarantee a high response rate. (SLD)

  3. Database design using NIAM (Nijssen Information Analysis Method) modeling

    SciTech Connect

    Stevens, N.H.

    1989-01-01

    The Nissjen Information Analysis Method (NIAM) is an information modeling technique based on semantics and founded in set theory. A NIAM information model is a graphical representation of the information requirements for some universe of discourse. Information models facilitate data integration and communication within an organization about data semantics. An information model is sometimes referred to as the semantic model or the conceptual schema. It helps in the logical and physical design and implementation of databases. NIAM information modeling is used at Sandia National Laboratories to design and implement relational databases containing engineering information which meet the users' information requirements. The paper focuses on the design of one database which satisfied the data needs of four disjoint but closely related applications. The applications as they existed before did not talk to each other even though they stored much of the same data redundantly. NIAM was used to determine the information requirements and design the integrated database. 6 refs., 7 figs.

  4. Integrated material and structural design method for flexible pavements. Volume 3: Laboratory design guide

    NASA Astrophysics Data System (ADS)

    Baladi, G. Y.

    1988-12-01

    The research quantified relationships between structural and material mix design parameters and documented a laboratory test procedure for examining mix design from a structural viewpoint. Laboratory asphalt mix design guidelines are presented. The guidelines are based upon the analysis of the results of laboratory static and cyclic load triaxial, indirect tensile, and flexural beam tests. The guidelines allow the highway engineer and the laboratory technician to tailor the asphalt mix design procedure to optimize the structural properties of the mix. Two mix design methods are covered: the Marshall mix design with minor modifications and the indirect tensile test. Analytical and statistical equations are also included to be able to calculate or estimate the structural properties of the mix.

  5. REVIEW OF PROPOSED METHODOLOGY FOR A RISK- INFORMED RELAXATION TO ASME SECTION XI APPENDIX G

    SciTech Connect

    Dickson, Terry L; Kirk, Mark

    2010-01-01

    The current regulations, as set forth by the United States Nuclear Regulatory Commission (NRC), to insure that light-water nuclear reactor pressure vessels (RPVs) maintain their structural integrity when subjected to planned normal reactor startup (heat-up) and shut-down (cool-down) transients are specified in Appendix G to 10 CFR Part 50, which incorporates by reference Appendix G to Section XI of the American Society of Mechanical Engineers (ASME) Code. The technical basis for these regulations are now recognized by the technical community as being conservative and some plants are finding it increasingly difficult to comply with the current regulations. Consequently, the nuclear industry has developed, and submitted to the ASME Code for approval, an alternative risk-informed methodology that reduces the conservatism and is consistent with the methods previously used to develop a risk-informed revision to the regulations for accidental transients such as pressurized thermal shock (PTS). The objective of the alternative methodology is to provide a relaxation to the current regulations which will provide more operational flexibility, particularly for reactor pressure vessels with relatively high irradiation levels and radiation sensitive materials, while continuing to provide reasonable assurance of adequate protection to public health and safety. The NRC and its contractor at Oak Ridge National Laboratory (ORNL) have recently performed an independent review of the industry proposed methodology. The NRC / ORNL review consisted of performing probabilistic fracture mechanics (PFM) analyses for a matrix of cool-down and heat-up rates, permutated over various reactor geometries and characteristics, each at multiple levels of embrittlement, including 60 effective full power years (EFPY) and beyond, for various postulated flaw characterizations. The objective of this review is to quantify the risk of a reactor vessel experiencing non-ductile fracture, and possible

  6. Computational methods for aerodynamic design using numerical optimization

    NASA Technical Reports Server (NTRS)

    Peeters, M. F.

    1983-01-01

    Five methods to increase the computational efficiency of aerodynamic design using numerical optimization, by reducing the computer time required to perform gradient calculations, are examined. The most promising method consists of drastically reducing the size of the computational domain on which aerodynamic calculations are made during gradient calculations. Since a gradient calculation requires the solution of the flow about an airfoil whose geometry was slightly perturbed from a base airfoil, the flow about the base airfoil is used to determine boundary conditions on the reduced computational domain. This method worked well in subcritical flow.

  7. Supersonic/hypersonic aerodynamic methods for aircraft design and analysis

    NASA Technical Reports Server (NTRS)

    Torres, Abel O.

    1992-01-01

    A methodology employed in engineering codes to predict aerodynamic characteristics over arbitrary supersonic/hypersonic configurations is considered. Engineering codes use a combination of simplified methods, based on geometrical impact angle and freestream conditions, to compute pressure distribution over the vehicle's surface in an efficient and timely manner. These approximate methods are valid for both hypersonic (Mach greater than 4) and lower speeds (Mach down to 2). It is concluded that the proposed methodology enables the user to obtain reasonable estimates of vehicle performance and engineering methods are valuable in the design process of these type of vehicles.

  8. Guidance for using mixed methods design in nursing practice research.

    PubMed

    Chiang-Hanisko, Lenny; Newman, David; Dyess, Susan; Piyakong, Duangporn; Liehr, Patricia

    2016-08-01

    The mixed methods approach purposefully combines both quantitative and qualitative techniques, enabling a multi-faceted understanding of nursing phenomena. The purpose of this article is to introduce three mixed methods designs (parallel; sequential; conversion) and highlight interpretive processes that occur with the synthesis of qualitative and quantitative findings. Real world examples of research studies conducted by the authors will demonstrate the processes leading to the merger of data. The examples include: research questions; data collection procedures and analysis with a focus on synthesizing findings. Based on experience with mixed methods studied, the authors introduce two synthesis patterns (complementary; contrasting), considering application for practice and implications for research.

  9. A Mixed Methods Investigation of Mixed Methods Sampling Designs in Social and Health Science Research

    ERIC Educational Resources Information Center

    Collins, Kathleen M. T.; Onwuegbuzie, Anthony J.; Jiao, Qun G.

    2007-01-01

    A sequential design utilizing identical samples was used to classify mixed methods studies via a two-dimensional model, wherein sampling designs were grouped according to the time orientation of each study's components and the relationship of the qualitative and quantitative samples. A quantitative analysis of 121 studies representing nine fields…

  10. A Mixed Methods Investigation of Mixed Methods Sampling Designs in Social and Health Science Research

    ERIC Educational Resources Information Center

    Collins, Kathleen M. T.; Onwuegbuzie, Anthony J.; Jiao, Qun G.

    2007-01-01

    A sequential design utilizing identical samples was used to classify mixed methods studies via a two-dimensional model, wherein sampling designs were grouped according to the time orientation of each study's components and the relationship of the qualitative and quantitative samples. A quantitative analysis of 121 studies representing nine fields…

  11. Comparison of methods for inverse design of radiant enclosures.

    SciTech Connect

    Fran­ca, Francis; Larsen, Marvin Elwood; Howell, John R.; Daun, Kyle; Leduc, Guillaume

    2005-03-01

    A particular inverse design problem is proposed as a benchmark for comparison of five solution techniques used in design of enclosures with radiating sources. The enclosure is three-dimensional and includes some surfaces that are diffuse and others that are specular diffuse. Two aspect ratios are treated. The problem is completely described, and solutions are presented as obtained by the Tikhonov method, truncated singular value decomposition, conjugate gradient regularization, quasi-Newton minimization, and simulated annealing. All of the solutions use a common set of exchange factors computed by Monte Carlo, and smoothed by a constrained maximum likelihood estimation technique that imposes conservation, reciprocity, and non-negativity. Solutions obtained by the various methods are presented and compared, and the relative advantages and disadvantages of these methods are summarized.

  12. Application of optical diffraction method in designing phase plates

    NASA Astrophysics Data System (ADS)

    Lei, Ze-Min; Sun, Xiao-Yan; Lv, Feng-Nian; Zhang, Zhen; Lu, Xing-Qiang

    2016-11-01

    Continuous phase plate (CPP), which has a function of beam shaping in laser systems, is one kind of important diffractive optics. Based on the Fourier transform of the Gerchberg-Saxton (G-S) algorithm for designing CPP, we proposed an optical diffraction method according to the real system conditions. A thin lens can complete the Fourier transform of the input signal and the inverse propagation of light can be implemented in a program. Using both of the two functions can realize the iteration process to calculate the near-field distribution of light and the far-field repeatedly, which is similar to the G-S algorithm. The results show that using the optical diffraction method can design a CPP for a complicated laser system, and make the CPP have abilities of beam shaping and phase compensation for the phase aberration of the system. The method can improve the adaptation of the phase plate in systems with phase aberrations.

  13. Designing waveforms for temporal encoding using a frequency sampling method.

    PubMed

    Gran, Fredrik; Jensen, Jørgen Arendt

    2007-10-01

    In this paper a method for designing waveforms for temporal encoding in medical ultrasound imaging is described. The method is based on least squares optimization and is used to design nonlinear frequency modulated signals for synthetic transmit aperture imaging. By using the proposed design method, the amplitude spectrum of the transmitted waveform can be optimized, such that most of the energy is transmitted where the transducer has large amplification. To test the design method, a waveform was designed for a BK8804 linear array transducer. The resulting nonlinear frequency modulated waveform was compared to a linear frequency modulated signal with amplitude tapering, previously used in clinical studies for synthetic transmit aperture imaging. The latter had a relatively flat spectrum which implied that the waveform tried to excite all frequencies including ones with low amplification. The proposed waveform, on the other hand, was designed so that only frequencies where the transducer had a large amplification were excited. Hereby, unnecessary heating of the transducer could be avoided and the signal-to-noise ratio could be increased. The experimental ultrasound scanner RASMUS was used to evaluate the method experimentally. Due to the careful waveform design optimized for the transducer at hand, a theoretic gain in signal-to-noise ratio of 4.9 dB compared to the reference excitation was found, even though the energy of the nonlinear frequency modulated signal was 71% of the energy of the reference signal. This was supported by a signal-to-noise ratio measurement and comparison in penetration depth, where an increase of 1 cm was found in favor for the proposed waveform. Axial and lateral resolutions at full-width half-maximum were compared in a water phantom at depths of 42, 62, 82, and 102 mm. The axial resolutions of the nonlinear frequency modulated signal were 0.62, 0.69, 0.60, and 0.60 mm, respectively. The corresponding axial resolutions for the reference

  14. Polarization in the reaction to health-risk information: a question of social position?

    PubMed

    Lindbladh, Eva; Lyttkens, Carl Hampus

    2003-08-01

    Dissemination of risk information is ubiquitous in contemporary society. We explore how individuals react in everyday life to health-risk information, based on what they report in personal interviews. Health-risk information was without exception recognized as unstable and inconsistent. This conformity, however, did not extend to the narratives regarding how health-risk information should be handled. Two opposite positions (ideal-typical strategies) are presented. Either you tend to process and evaluate new information or you tend to ignore it as a whole. Our attempt to reveal the underlying rationality in these two very different approaches involved the exploration of three different avenues of interpretation and brings together two scientific paradigms--economics and sociology--that provide the framework for our analysis. First, we suggest that a greater long-term experience of explicit choice implies that this kind of action becomes more natural and less resource consuming, whereas a reliance on habits in daily life--a natural adjustment to a lack of resources--makes it is more costly to bother about new information. Second, with fewer resources in the short run, fewer opportunities to mitigate bad outcomes, and greater exposure to social and material risks, one is less likely to devote resources to deal with health-risk information. Third, there are several possible links between a low propensity to take account of risk information and a high relative importance of genuine uncertainty in one's life. These theoretical perspectives provide a viable set of hypotheses regarding mechanisms that may contribute to social differences in the response to health-risk information.

  15. Tuning Parameters in Heuristics by Using Design of Experiments Methods

    NASA Technical Reports Server (NTRS)

    Arin, Arif; Rabadi, Ghaith; Unal, Resit

    2010-01-01

    With the growing complexity of today's large scale problems, it has become more difficult to find optimal solutions by using exact mathematical methods. The need to find near-optimal solutions in an acceptable time frame requires heuristic approaches. In many cases, however, most heuristics have several parameters that need to be "tuned" before they can reach good results. The problem then turns into "finding best parameter setting" for the heuristics to solve the problems efficiently and timely. One-Factor-At-a-Time (OFAT) approach for parameter tuning neglects the interactions between parameters. Design of Experiments (DOE) tools can be instead employed to tune the parameters more effectively. In this paper, we seek the best parameter setting for a Genetic Algorithm (GA) to solve the single machine total weighted tardiness problem in which n jobs must be scheduled on a single machine without preemption, and the objective is to minimize the total weighted tardiness. Benchmark instances for the problem are available in the literature. To fine tune the GA parameters in the most efficient way, we compare multiple DOE models including 2-level (2k ) full factorial design, orthogonal array design, central composite design, D-optimal design and signal-to-noise (SIN) ratios. In each DOE method, a mathematical model is created using regression analysis, and solved to obtain the best parameter setting. After verification runs using the tuned parameter setting, the preliminary results for optimal solutions of multiple instances were found efficiently.

  16. Framework for modeling high-impact, low-frequency power grid events to support risk-informed decisions

    SciTech Connect

    Veeramany, Arun; Unwin, Stephen D.; Coles, Garill A.; Dagle, Jeffery E.; Millard, David W.; Yao, Juan; Glantz, Cliff S.; Gourisetti, Sri N. G.

    2016-06-25

    Natural and man-made hazardous events resulting in loss of grid infrastructure assets challenge the security and resilience of the electric power grid. However, the planning and allocation of appropriate contingency resources for such events requires an understanding of their likelihood and the extent of their potential impact. Where these events are of low likelihood, a risk-informed perspective on planning can be difficult, as the statistical basis needed to directly estimate the probabilities and consequences of their occurrence does not exist. Because risk-informed decisions rely on such knowledge, a basis for modeling the risk associated with high-impact, low-frequency events (HILFs) is essential. Insights from such a model indicate where resources are most rationally and effectively expended. A risk-informed realization of designing and maintaining a grid resilient to HILFs will demand consideration of a spectrum of hazards/threats to infrastructure integrity, an understanding of their likelihoods of occurrence, treatment of the fragilities of critical assets to the stressors induced by such events, and through modeling grid network topology, the extent of damage associated with these scenarios. The model resulting from integration of these elements will allow sensitivity assessments based on optional risk management strategies, such as alternative pooling, staging and logistic strategies, and emergency contingency planning. This study is focused on the development of an end-to-end HILF risk-assessment framework. Such a framework is intended to provide the conceptual and overarching technical basis for the development of HILF risk models that can inform decision-makers across numerous stakeholder groups in directing resources optimally towards the management of risks to operational continuity.

  17. Optimal pulse design in quantum control: A unified computational method

    PubMed Central

    Li, Jr-Shin; Ruths, Justin; Yu, Tsyr-Yan; Arthanari, Haribabu; Wagner, Gerhard

    2011-01-01

    Many key aspects of control of quantum systems involve manipulating a large quantum ensemble exhibiting variation in the value of parameters characterizing the system dynamics. Developing electromagnetic pulses to produce a desired evolution in the presence of such variation is a fundamental and challenging problem in this research area. We present such robust pulse designs as an optimal control problem of a continuum of bilinear systems with a common control function. We map this control problem of infinite dimension to a problem of polynomial approximation employing tools from geometric control theory. We then adopt this new notion and develop a unified computational method for optimal pulse design using ideas from pseudospectral approximations, by which a continuous-time optimal control problem of pulse design can be discretized to a constrained optimization problem with spectral accuracy. Furthermore, this is a highly flexible and efficient numerical method that requires low order of discretization and yields inherently smooth solutions. We demonstrate this method by designing effective broadband π/2 and π pulses with reduced rf energy and pulse duration, which show significant sensitivity enhancement at the edge of the spectrum over conventional pulses in 1D and 2D NMR spectroscopy experiments. PMID:21245345

  18. Novel TMS coils designed using an inverse boundary element method

    NASA Astrophysics Data System (ADS)

    Cobos Sánchez, Clemente; María Guerrero Rodriguez, Jose; Quirós Olozábal, Ángel; Blanco-Navarro, David

    2017-01-01

    In this work, a new method to design TMS coils is presented. It is based on the inclusion of the concept of stream function of a quasi-static electric current into a boundary element method. The proposed TMS coil design approach is a powerful technique to produce stimulators of arbitrary shape, and remarkably versatile as it permits the prototyping of many different performance requirements and constraints. To illustrate the power of this approach, it has been used for the design of TMS coils wound on rectangular flat, spherical and hemispherical surfaces, subjected to different constraints, such as minimum stored magnetic energy or power dissipation. The performances of such coils have been additionally described; and the torque experienced by each stimulator in the presence of a main magnetic static field have theoretically found in order to study the prospect of using them to perform TMS and fMRI concurrently. The obtained results show that described method is an efficient tool for the design of TMS stimulators, which can be applied to a wide range of coil geometries and performance requirements.

  19. Non-contact electromagnetic exciter design with linear control method

    NASA Astrophysics Data System (ADS)

    Wang, Lin; Xiong, Xianzhi; Xu, Hua

    2017-01-01

    A non-contact type force actuator is necessary for studying the dynamic performance of a high-speed spindle system owing to its high-speed operating conditions. A non-contact electromagnetic exciter is designed for identifying the dynamic coefficients of journal bearings in high-speed grinding spindles. A linear force control method is developed based on PID controller. The influence of amplitude and frequency of current, misalignment and rotational speed on magnetic field and excitation force is investigated based on two-dimensional finite element analysis. The electromagnetic excitation force is measured with the auxiliary coils and calibrated by load cells. The design is validated by the experimental results. Theoretical and experimental investigations show that the proposed design can accurately generate linear excitation force with sufficiently large amplitude and higher signal to noise ratio. Moreover, the fluctuations in force amplitude are reduced to a greater extent with the designed linear control method even when the air gap changes due to the rotor vibration at high-speed conditions. Besides, it is possible to apply various types of excitations: constant, synchronous, and non-synchronous excitation forces based on the proposed linear control method. This exciter can be used as linear-force exciting and controlling system for dynamic performance study of different high-speed rotor-bearing systems.

  20. Design method of coaxial reflex hollow beam generator

    NASA Astrophysics Data System (ADS)

    Wang, Jiake; Xu, Jia; Fu, Yuegang; He, Wenjun; Zhu, Qifan

    2016-10-01

    In view of the light energy loss in central obscuration of coaxial reflex optical system, the design method of a kind of hollow beam generator is introduced. First of all, according to the geometrical parameter and obscuration ratio of front-end coaxial reflex optical system, calculate the required physical dimension of hollow beam, and get the beam expanding rate of the hollow beam generator according to the parameters of the light source. Choose the better enlargement ratio of initial expanding system using the relational expression of beam expanding rate and beam expanding rate of initial system; the traditional design method of the reflex optical system is used to design the initial optical system, and then the position of rotation axis of the hollow beam generator can be obtained through the rotation axis translation formula. Intercept the initial system bus bar using the rotation axis after the translation, and rotate the bus bar around the rotation axis for 360°, so that two working faces of the hollow beam generator can be got. The hollow beam generator designed by this method can get the hollow beam that matches the front-end coaxial reflex optical system, improving the energy utilization ratio of beam and effectively reducing the back scattering of transmission system.

  1. The future of prodrugs - design by quantum mechanics methods.

    PubMed

    Karaman, Rafik; Fattash, Beesan; Qtait, Alaa

    2013-05-01

    The revolution in computational chemistry greatly impacted the drug design and delivery fields, in general, and recently the utilization of the prodrug approach in particular. The use of ab initio, semiempirical and molecular mechanics methods to understand organic reaction mechanisms of certain processes, especially intramolecular reactions, has opened the door to design and to rapidly produce safe and efficacious delivery of a wide range of active small molecule and biotherapeutics such as prodrugs. This article provides the readers with a concise overview of this modern approach to prodrug design. The use of computational approaches, such as density functional theory (DFT), semiempirical and ab initio molecular orbital methods, in modern prodrugs design will be discussed. The novel prodrug approach to be reported in this review implies prodrug design based on enzyme model (mimicking enzyme catalysis) that has been utilized to understand how enzymes work. The tool used in the design is a computational approach consisting of calculations using molecular orbital and molecular mechanics methods (DFT, ab initio and MM2) and correlations between experimental and calculated values of intramolecular processes that were used to understand the mechanism by which enzymes might exert their high rates catalysis. The future of prodrug technology is exciting yet extremely challenging. Advances must be made in understanding the chemistry of many organic reactions that can be effectively utilized to enable the development of even more types of prodrugs. Despite the increase in the number of marketed prodrugs, we have only started to appreciate the potential of the prodrug approach in modern drug development, and the coming years will witness many novel prodrug innovations.

  2. Behavioral response to contamination risk information in a spatially explicit groundwater environment: Experimental evidence

    NASA Astrophysics Data System (ADS)

    Li, Jingyuan; Michael, Holly A.; Duke, Joshua M.; Messer, Kent D.; Suter, Jordan F.

    2014-08-01

    This paper assesses the effectiveness of aquifer monitoring information in achieving more sustainable use of a groundwater resource in the absence of management policy. Groundwater user behavior in the face of an irreversible contamination threat is studied by applying methods of experimental economics to scenarios that combine a physics-based, spatially explicit, numerical groundwater model with different representations of information about an aquifer and its risk of contamination. The results suggest that the threat of catastrophic contamination affects pumping decisions: pumping is significantly reduced in experiments where contamination is possible compared to those where pumping cost is the only factor discouraging groundwater use. The level of information about the state of the aquifer also affects extraction behavior. Pumping rates differ when information that synthesizes data on aquifer conditions (a "risk gauge") is provided, despite invariant underlying economic incentives, and this result does not depend on whether the risk information is location-specific or from a whole aquifer perspective. Interestingly, users increase pumping when the risk gauge signals good aquifer status compared to a no-gauge treatment. When the gauge suggests impending contamination, however, pumping declines significantly, resulting in a lower probability of contamination. The study suggests that providing relatively simple aquifer condition guidance derived from monitoring data can lead to more sustainable use of groundwater resources.

  3. The characterization of kerogen-analytical limitations and method design

    SciTech Connect

    Larter, S.R.

    1987-04-01

    Methods suitable for high resolution total molecular characterization of kerogens and other polymeric SOM are necessary for a quantitative understanding of hydrocarbon maturation and migration phenomena in addition to being a requirement for a systematic understanding of kerogen based fuel utilization. Gas chromatographic methods, in conjunction with analytical pyrolysis methods, have proven successful in the rapid superficial characterization of kerogen pyrolysates. Most applications involve qualitative or semi-quantitative assessment of the relative concentration of aliphatic, aromatic, or oxygen-containing species in a kerogen pyrolysate. More recently, the use of alkylated polystyrene internal standards has allowed the direct determination of parameters related to the abundance of, for example, normal alkyl groups or single ring aromatic species in kerogens. The future of methods of this type for improved kerogen typing is critically discussed. The conceptual design and feasibility of methods suitable for the more complete characterization of complex geopolymers on the molecular level is discussed with practical examples.

  4. Design of transonic compressor cascades using hodograph method

    NASA Technical Reports Server (NTRS)

    Chen, Zuoyi; Guo, Jingrong

    1991-01-01

    The use of the Hodograph Method in the design of a transonic compressor cascade is discussed. The design of the flow mode in the transonic compressor cascade must be as follows: the flow in the nozzle part should be uniform and smooth; the location of the sonic line should be reasonable; and the aerodynamic character of the flow canal in the subsonic region should be met. The rate through cascade may be determined by the velocity distribution in the subsonic region (i.e., by the numerical solution of the Chaplygin equation). The supersonic sections A'C' and AD are determined by the analytical solution of the Mixed-Type Hodograph equation.

  5. Rays inserting method (RIM) to design dielectric optical devices

    NASA Astrophysics Data System (ADS)

    Taskhiri, Mohammad Mahdi; Khalaj Amirhosseini, Mohammad

    2017-01-01

    In this article, a novel approach, called Rays Inserted Method (RIM), is introduced to design dielectric optical devices. In this approach, some rays are inserted between two ends of desired device and then the refractive index of the points along the route of rays are obtained. The validity of the introduced approach is verified by designing three types of optical devices, i.e. power splitter, bend, and flat lens. The results are confirmed with numerical simulations by the means of FDTD scheme at the frequency of 100 GHz.

  6. Current methods of epitope identification for cancer vaccine design.

    PubMed

    Cherryholmes, Gregory A; Stanton, Sasha E; Disis, Mary L

    2015-12-16

    The importance of the immune system in tumor development and progression has been emerging in many cancers. Previous cancer vaccines have not shown long-term clinical benefit possibly because were not designed to avoid eliciting regulatory T-cell responses that inhibit the anti-tumor immune response. This review will examine different methods of identifying epitopes derived from tumor associated antigens suitable for immunization and the steps used to design and validate peptide epitopes to improve efficacy of anti-tumor peptide-based vaccines. Focusing on in silico prediction algorithms, we survey the advantages and disadvantages of current cancer vaccine prediction tools. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Material Design, Selection, and Manufacturing Methods for System Sustainment

    SciTech Connect

    David Sowder, Jim Lula, Curtis Marshall

    2010-02-18

    This paper describes a material selection and validation process proven to be successful for manufacturing high-reliability long-life product. The National Secure Manufacturing Center business unit of the Kansas City Plant (herein called KCP) designs and manufactures complex electrical and mechanical components used in extreme environments. The material manufacturing heritage is founded in the systems design to manufacturing practices that support the U.S. Department of Energy’s National Nuclear Security Administration (DOE/NNSA). Material Engineers at KCP work with the systems designers to recommend materials, develop test methods, perform analytical analysis of test data, define cradle to grave needs, present final selection and fielding. The KCP material engineers typically will maintain cost control by utilizing commercial products when possible, but have the resources and to develop and produce unique formulations as necessary. This approach is currently being used to mature technologies to manufacture materials with improved characteristics using nano-composite filler materials that will enhance system design and production. For some products the engineers plan and carry out science-based life-cycle material surveillance processes. Recent examples of the approach include refurbished manufacturing of the high voltage power supplies for cockpit displays in operational aircraft; dry film lubricant application to improve bearing life for guided munitions gyroscope gimbals, ceramic substrate design for electrical circuit manufacturing, and tailored polymeric materials for various systems. The following examples show evidence of KCP concurrent design-to-manufacturing techniques used to achieve system solutions that satisfy or exceed demanding requirements.

  8. Application of the CSCM method to the design of wedge cavities. [Conservative Supra Characteristic Method

    NASA Technical Reports Server (NTRS)

    Venkatapathy, Ethiraj; Nystrom, G. A.; Bardina, J.; Lombard, C. K.

    1987-01-01

    This paper describes the application of the conservative supra characteristic method (CSCM) to predict the flow around two-dimensional slot injection cooled cavities in hypersonic flow. Seven different numerical solutions are presented that model three different experimental designs. The calculations manifest outer flow conditions including the effects of nozzle/lip geometry, angle of attack, nozzle inlet conditions, boundary and shear layer growth and turbulance on the surrounding flow. The calculations were performed for analysis prior to wind tunnel testing for sensitivity studies early in the design process. Qualitative and quantitative understanding of the flows for each of the cavity designs and design recommendations are provided. The present paper demonstrates the ability of numerical schemes, such as the CSCM method, to play a significant role in the design process.

  9. Application of the CSCM method to the design of wedge cavities. [Conservative Supra Characteristic Method

    NASA Technical Reports Server (NTRS)

    Venkatapathy, Ethiraj; Nystrom, G. A.; Bardina, J.; Lombard, C. K.

    1987-01-01

    This paper describes the application of the conservative supra characteristic method (CSCM) to predict the flow around two-dimensional slot injection cooled cavities in hypersonic flow. Seven different numerical solutions are presented that model three different experimental designs. The calculations manifest outer flow conditions including the effects of nozzle/lip geometry, angle of attack, nozzle inlet conditions, boundary and shear layer growth and turbulance on the surrounding flow. The calculations were performed for analysis prior to wind tunnel testing for sensitivity studies early in the design process. Qualitative and quantitative understanding of the flows for each of the cavity designs and design recommendations are provided. The present paper demonstrates the ability of numerical schemes, such as the CSCM method, to play a significant role in the design process.

  10. Unified computational method for design of fluid loop systems

    NASA Astrophysics Data System (ADS)

    Furukawa, Masao

    1991-12-01

    Various kinds of empirical formulas of Nusselt numbers, fanning friction factors, and pressure loss coefficients were collected and reviewed with the object of constructing a common basis of design calculations of pumped fluid loop systems. The practical expressions obtained after numerical modifications are listed in tables with identification numbers corresponding to configurations of the flow passages. Design procedure of a cold plate and of a space radiator are clearly shown in a series of mathematical relations coupled with a number of detailed expressions which are put in the tables in order of numerical computations. Weight estimate models and several pump characteristics are given in the tables as a result of data regression. A unified computational method based upon the above procedure is presented for preliminary design analyses of a fluid loop system consisting of cold plates, plane radiators, mechanical pumps, valves, and so on.

  11. USER-derived cloning methods and their primer design.

    PubMed

    Salomonsen, Bo; Mortensen, Uffe H; Halkier, Barbara A

    2014-01-01

    Uracil excision-based cloning through USER™ (Uracil-Specific Excision Reagent) is an efficient ligase-free cloning technique that comprises USER cloning, USER fusion, and USER cassette-free (UCF) USER fusion. These USER-derived cloning techniques enable seamless assembly of multiple DNA fragments in one construct. Though governed by a few simple rules primer design for USER-based fusion of PCR fragments can prove time-consuming for inexperienced users. The Primer Help for USER (PHUSER) software is an easy-to-use primer design tool for USER-based methods. In this chapter, we present a PHUSER software protocol for designing primers for USER-derived cloning techniques.

  12. A simple design method of negative refractive index metamaterials

    NASA Astrophysics Data System (ADS)

    Kim, Dongho; Lee, Wangju; Choi, Jaeick

    2009-11-01

    We propose a very simple design method of negative refractive index (NRI) materials that can overcome some drawbacks of conventional resonant-type NRI materials. The proposed NRI materials consist of single or double metallic patterns printed on a dielectric substrate. Our metamaterials (MTMs) show two properties that are different from other types of MTMs in obtaining effective negative values of permittivity ( ɛ) and permeability ( μ) simultaneously; the geometrical outlines of the metallic patterns are not confined within any specific shape, and the metallic patterns are printed on only one side of the dielectric substrate. Therefore, they are very easy to design and fabricate using common printed circuit board (PCB) technology according to the appropriate application. Excellent agreement between the experiment and prediction data ensures the validity of our design approach.

  13. Applying Human-Centered Design Methods to Scientific Communication Products

    NASA Astrophysics Data System (ADS)

    Burkett, E. R.; Jayanty, N. K.; DeGroot, R. M.

    2016-12-01

    Knowing your users is a critical part of developing anything to be used or experienced by a human being. User interviews, journey maps, and personas are all techniques commonly employed in human-centered design practices because they have proven effective for informing the design of products and services that meet the needs of users. Many non-designers are unaware of the usefulness of personas and journey maps. Scientists who are interested in developing more effective products and communication can adopt and employ user-centered design approaches to better reach intended audiences. Journey mapping is a qualitative data-collection method that captures the story of a user's experience over time as related to the situation or product that requires development or improvement. Journey maps help define user expectations, where they are coming from, what they want to achieve, what questions they have, their challenges, and the gaps and opportunities that can be addressed by designing for them. A persona is a tool used to describe the goals and behavioral patterns of a subset of potential users or customers. The persona is a qualitative data model that takes the form of a character profile, built upon data about the behaviors and needs of multiple users. Gathering data directly from users avoids the risk of basing models on assumptions, which are often limited by misconceptions or gaps in understanding. Journey maps and user interviews together provide the data necessary to build the composite character that is the persona. Because a persona models the behaviors and needs of the target audience, it can then be used to make informed product design decisions. We share the methods and advantages of developing and using personas and journey maps to create more effective science communication products.

  14. 77 FR 32632 - Ambient Air Monitoring Reference and Equivalent Methods: Designation of Three New Equivalent Methods

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-01

    ... AGENCY Ambient Air Monitoring Reference and Equivalent Methods: Designation of Three New Equivalent... of lead (Pb) in the ambient air. FOR FURTHER INFORMATION CONTACT: Robert Vanderpool, Human Exposure... CFR Part 53, the EPA evaluates various methods for monitoring the concentrations of those ambient...

  15. Helicopter flight-control design using an H(2) method

    NASA Technical Reports Server (NTRS)

    Takahashi, Marc D.

    1991-01-01

    Rate-command and attitude-command flight-control designs for a UH-60 helicopter in hover are presented and were synthesized using an H(2) method. Using weight functions, this method allows the direct shaping of the singular values of the sensitivity, complementary sensitivity, and control input transfer-function matrices to give acceptable feedback properties. The designs were implemented on the Vertical Motion Simulator, and four low-speed hover tasks were used to evaluate the control system characteristics. The pilot comments from the accel-decel, bob-up, hovering turn, and side-step tasks indicated good decoupling and quick response characteristics. However, an underlying roll PIO tendency was found to exist away from the hover condition, which was caused by a flap regressing mode with insufficient damping.

  16. Optical design and active optics methods in astronomy

    NASA Astrophysics Data System (ADS)

    Lemaitre, Gerard R.

    2013-03-01

    Optical designs for astronomy involve implementation of active optics and adaptive optics from X-ray to the infrared. Developments and results of active optics methods for telescopes, spectrographs and coronagraph planet finders are presented. The high accuracy and remarkable smoothness of surfaces generated by active optics methods also allow elaborating new optical design types with high aspheric and/or non-axisymmetric surfaces. Depending on the goal and performance requested for a deformable optical surface analytical investigations are carried out with one of the various facets of elasticity theory: small deformation thin plate theory, large deformation thin plate theory, shallow spherical shell theory, weakly conical shell theory. The resulting thickness distribution and associated bending force boundaries can be refined further with finite element analysis.

  17. National Tuberculosis Genotyping and Surveillance Network: Design and Methods

    PubMed Central

    Braden, Christopher R.; Schable, Barbara A.; Onorato, Ida M.

    2002-01-01

    The National Tuberculosis Genotyping and Surveillance Network was established in 1996 to perform a 5-year, prospective study of the usefulness of genotyping Mycobacterium tuberculosis isolates to tuberculosis control programs. Seven sentinel sites identified all new cases of tuberculosis, collected information on patients and contacts, and obtained patient isolates. Seven genotyping laboratories performed DNA fingerprinting analysis by the international standard IS6110 method. BioImage Whole Band Analyzer software was used to analyze patterns, and distinct patterns were assigned unique designations. Isolates with six or fewer bands on IS6110 patterns were also spoligotyped. Patient data and genotyping designations were entered in a relational database and merged with selected variables from the national surveillance database. In two related databases, we compiled the results of routine contact investigations and the results of investigations of the relationships of patients who had isolates with matching genotypes. We describe the methods used in the study. PMID:12453342

  18. Simplified Analysis Methods for Primary Load Designs at Elevated Temperatures

    SciTech Connect

    Carter, Peter; Jetter, Robert I; Sham, Sam

    2011-01-01

    The use of simplified (reference stress) analysis methods is discussed and illustrated for primary load high temperature design. Elastic methods are the basis of the ASME Section III, Subsection NH primary load design procedure. There are practical drawbacks with this approach, particularly for complex geometries and temperature gradients. The paper describes an approach which addresses these difficulties through the use of temperature-dependent elastic-perfectly plastic analysis. Correction factors are defined to address difficulties traditionally associated with discontinuity stresses, inelastic strain concentrations and multiaxiality. A procedure is identified to provide insight into how this approach could be implemented but clearly there is additional work to be done to define and clarify the procedural steps to bring it to the point where it could be adapted into code language.

  19. Preliminary demonstration of a robust controller design method

    NASA Technical Reports Server (NTRS)

    Anderson, L. R.

    1980-01-01

    Alternative computational procedures for obtaining a feedback control law which yields a control signal based on measurable quantitites are evaluated. The three methods evaluated are: (1) the standard linear quadratic regulator design model; (2) minimization of the norm of the feedback matrix, k via nonlinear programming subject to the constraint that the closed loop eigenvalues be in a specified domain in the complex plane; and (3) maximize the angles between the closed loop eigenvectors in combination with minimizing the norm of K also via the constrained nonlinear programming. The third or robust design method was chosen to yield a closed loop system whose eigenvalues are insensitive to small changes in the A and B matrices. The relationship between orthogonality of closed loop eigenvectors and the sensitivity of closed loop eigenvalues is described. Computer programs are described.

  20. Attenuator design method for dedicated whole-core CT.

    PubMed

    Li, Mengfei; Zhao, Yunsong; Zhang, Peng

    2016-10-03

    In whole-core CT imaging, scanned data corresponding to the central portion of a cylindrical core often suffer from photon starvation, because increasing photon flux will cause overflow on some detector units under the restriction of detector dynamic range. Either photon starvation or data overflow will lead to increased noise or severe artifacts in the reconstructed CT image. In addition, cupping shaped beam hardening artifacts also appear in the whole-core CT image. In this paper, we present a method to design an attenuator for cone beam whole-core CT, which not only reduces the dynamic range requirement for high SNR data scanning, but also corrects beam hardening artifacts. Both simulation and real data are employed to verify our design method.

  1. A Requirements-Driven Optimization Method for Acoustic Treatment Design

    NASA Technical Reports Server (NTRS)

    Berton, Jeffrey J.

    2016-01-01

    Acoustic treatment designers have long been able to target specific noise sources inside turbofan engines. Facesheet porosity and cavity depth are key design variables of perforate-over-honeycomb liners that determine levels of noise suppression as well as the frequencies at which suppression occurs. Layers of these structures can be combined to create a robust attenuation spectrum that covers a wide range of frequencies. Looking to the future, rapidly-emerging additive manufacturing technologies are enabling new liners with multiple degrees of freedom, and new adaptive liners with variable impedance are showing promise. More than ever, there is greater flexibility and freedom in liner design. Subject to practical considerations, liner design variables may be manipulated to achieve a target attenuation spectrum. But characteristics of the ideal attenuation spectrum can be difficult to know. Many multidisciplinary system effects govern how engine noise sources contribute to community noise. Given a hardwall fan noise source to be suppressed, and using an analytical certification noise model to compute a community noise measure of merit, the optimal attenuation spectrum can be derived using multidisciplinary systems analysis methods. The subject of this paper is an analytical method that derives the ideal target attenuation spectrum that minimizes noise perceived by observers on the ground.

  2. A method for the aerodynamic design of dry powder inhalers.

    PubMed

    Ertunç, O; Köksoy, C; Wachtel, H; Delgado, A

    2011-09-15

    An inhaler design methodology was developed and then used to design a new dry powder inhaler (DPI) which aimed to fulfill two main performance requirements. The first requirement was that the patient should be able to completely empty the dry powder from the blister in which it is stored by inspiratory effort alone. The second requirement was that the flow resistance of the inhaler should be geared to optimum patient comfort. The emptying of a blister is a two-phase flow problem, whilst the adjustment of the flow resistance is an aerodynamic design problem. The core of the method comprised visualization of fluid and particle flow in upscaled prototypes operated in water. The prototypes and particles were upscaled so that dynamic similarity conditions were approximated as closely as possible. The initial step in the design method was to characterize different blister prototypes by measurements of their flow resistance and particle emptying performance. The blisters were then compared with regard to their aerodynamic performance and their ease of production. Following selection of candidate blisters, the other components such as needle, bypass and mouthpiece were dimensioned on the basis of node-loop operations and validation experiments. The final shape of the inhaler was achieved by experimental iteration. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Application of an optimization method to high performance propeller designs

    NASA Technical Reports Server (NTRS)

    Li, K. C.; Stefko, G. L.

    1984-01-01

    The application of an optimization method to determine the propeller blade twist distribution which maximizes propeller efficiency is presented. The optimization employs a previously developed method which has been improved to include the effects of blade drag, camber and thickness. Before the optimization portion of the computer code is used, comparisons of calculated propeller efficiencies and power coefficients are made with experimental data for one NACA propeller at Mach numbers in the range of 0.24 to 0.50 and another NACA propeller at a Mach number of 0.71 to validate the propeller aerodynamic analysis portion of the computer code. Then comparisons of calculated propeller efficiencies for the optimized and the original propellers show the benefits of the optimization method in improving propeller performance. This method can be applied to the aerodynamic design of propellers having straight, swept, or nonplanar propeller blades.

  4. Evaluation of Methods for Multidisciplinary Design Optimization (MDO). Part 2

    NASA Technical Reports Server (NTRS)

    Kodiyalam, Srinivas; Yuan, Charles; Sobieski, Jaroslaw (Technical Monitor)

    2000-01-01

    A new MDO method, BLISS, and two different variants of the method, BLISS/RS and BLISS/S, have been implemented using iSIGHT's scripting language and evaluated in this report on multidisciplinary problems. All of these methods are based on decomposing a modular system optimization system into several subtasks optimization, that may be executed concurrently, and the system optimization that coordinates the subtasks optimization. The BLISS method and its variants are well suited for exploiting the concurrent processing capabilities in a multiprocessor machine. Several steps, including the local sensitivity analysis, local optimization, response surfaces construction and updates are all ideally suited for concurrent processing. Needless to mention, such algorithms that can effectively exploit the concurrent processing capabilities of the compute servers will be a key requirement for solving large-scale industrial design problems, such as the automotive vehicle problem detailed in Section 3.4.

  5. Computational methods for drug design and discovery: focus on China.

    PubMed

    Zheng, Mingyue; Liu, Xian; Xu, Yuan; Li, Honglin; Luo, Cheng; Jiang, Hualiang

    2013-10-01

    In the past decades, China's computational drug design and discovery research has experienced fast development through various novel methodologies. Application of these methods spans a wide range, from drug target identification to hit discovery and lead optimization. In this review, we firstly provide an overview of China's status in this field and briefly analyze the possible reasons for this rapid advancement. The methodology development is then outlined. For each selected method, a short background precedes an assessment of the method with respect to the needs of drug discovery, and, in particular, work from China is highlighted. Furthermore, several successful applications of these methods are illustrated. Finally, we conclude with a discussion of current major challenges and future directions of the field.

  6. A method of designing clinical trials for combination drugs.

    PubMed

    Pigeon, J G; Copenhaver, M D; Whipple, J P

    1992-06-15

    Many pharmaceutical companies are now exploring combination drug therapies as an alternative to monotherapy. Consequently, it is of interest to investigate the simultaneous dose response relationship of two active drugs to select the lowest effective combination. In this paper, we propose a method for designing clinical trials for drug combinations that seems to offer several advantages over the 4 x 3 or even larger factorial studies that have been used to date. In addition, our proposed method provides a convenient formula for calculating the required sample size.

  7. Synthesis of aircraft structures using integrated design and analysis methods

    NASA Technical Reports Server (NTRS)

    Sobieszczanski-Sobieski, J.; Goetz, R. C.

    1978-01-01

    A systematic research is reported to develop and validate methods for structural sizing of an airframe designed with the use of composite materials and active controls. This research program includes procedures for computing aeroelastic loads, static and dynamic aeroelasticity, analysis and synthesis of active controls, and optimization techniques. Development of the methods is concerned with the most effective ways of integrating and sequencing the procedures in order to generate structural sizing and the associated active control system, which is optimal with respect to a given merit function constrained by strength and aeroelasticity requirements.

  8. Uncertainty-Based Design Methods for Flow-Structure Interactions

    DTIC Science & Technology

    2007-06-01

    07 Final _ 2/01/05 - 01/31/07 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Uncertainty-based Design Methods for Flow- N00014-04-1-0007 Structure ...project is to develop advanced tools for efficient simulations of flow- structure interactions that account for random excitation and uncertain input...with emphasis on realistic three-dimensional nonlinear representatiol of the structures of interest. This capability will set the foundation for the

  9. A design method for constellation of lifting reentry vehicles

    NASA Astrophysics Data System (ADS)

    Xiang, Yu; Kun, Liu

    2017-03-01

    As the reachable domain of a single lifting reentry vehicle is not large enough to cover the whole globe in a short time, which is disadvantageous to responsive operation, it is of great significance to study on how to construct a constellation of several lifting reentry vehicles to responsively reach any point of the globe. This paper addresses a design method for such a constellation. Firstly, an approach for calculating the reachable domain of a single lifting reentry vehicle is given, using the combination of Gauss Pseudospectral Method and SQP method. Based on that, the entire reachable domain taking the limit of responsive time into consideration is simplified reasonably to reduce the complexity of the problem. Secondly, a Streets-of-Coverage (SOC) method is used to design the constellation and the parameters of the constellation are optimized through simple analysis and comparison. Lastly, a point coverage simulation method is utilized to verify the correctness of the optimization result. The verified result shows that 6 lifting reentry vehicles whose maximum lift-to-drag ratio is 1.7 can reach nearly any point on the earth's surface between -50° and 50° in less than 90 minutes.

  10. Design Methods for Load-bearing Elements from Crosslaminated Timber

    NASA Astrophysics Data System (ADS)

    Vilguts, A.; Serdjuks, D.; Goremikins, V.

    2015-11-01

    Cross-laminated timber is an environmentally friendly material, which possesses a decreased level of anisotropy in comparison with the solid and glued timber. Cross-laminated timber could be used for load-bearing walls and slabs of multi-storey timber buildings as well as decking structures of pedestrian and road bridges. Design methods of cross-laminated timber elements subjected to bending and compression with bending were considered. The presented methods were experimentally validated and verified by FEM. Two cross-laminated timber slabs were tested at the action of static load. Pine wood was chosen as a board's material. Freely supported beam with the span equal to 1.9 m, which was loaded by the uniformly distributed load, was a design scheme of the considered plates. The width of the plates was equal to 1 m. The considered cross-laminated timber plates were analysed by FEM method. The comparison of stresses acting in the edge fibres of the plate and the maximum vertical displacements shows that both considered methods can be used for engineering calculations. The difference between the results obtained experimentally and analytically is within the limits from 2 to 31%. The difference in results obtained by effective strength and stiffness and transformed sections methods was not significant.

  11. Achieving integration in mixed methods designs-principles and practices.

    PubMed

    Fetters, Michael D; Curry, Leslie A; Creswell, John W

    2013-12-01

    Mixed methods research offers powerful tools for investigating complex processes and systems in health and health care. This article describes integration principles and practices at three levels in mixed methods research and provides illustrative examples. Integration at the study design level occurs through three basic mixed method designs-exploratory sequential, explanatory sequential, and convergent-and through four advanced frameworks-multistage, intervention, case study, and participatory. Integration at the methods level occurs through four approaches. In connecting, one database links to the other through sampling. With building, one database informs the data collection approach of the other. When merging, the two databases are brought together for analysis. With embedding, data collection and analysis link at multiple points. Integration at the interpretation and reporting level occurs through narrative, data transformation, and joint display. The fit of integration describes the extent the qualitative and quantitative findings cohere. Understanding these principles and practices of integration can help health services researchers leverage the strengths of mixed methods.

  12. Gradient-based optimum aerodynamic design using adjoint methods

    NASA Astrophysics Data System (ADS)

    Xie, Lei

    2002-09-01

    Continuous adjoint methods and optimal control theory are applied to a pressure-matching inverse design problem of quasi 1-D nozzle flows. Pontryagin's Minimum Principle is used to derive the adjoint system and the reduced gradient of the cost functional. The properties of adjoint variables at the sonic throat and the shock location are studied, revealing a log-arithmic singularity at the sonic throat and continuity at the shock location. A numerical method, based on the Steger-Warming flux-vector-splitting scheme, is proposed to solve the adjoint equations. This scheme can finely resolve the singularity at the sonic throat. A non-uniform grid, with points clustered near the throat region, can resolve it even better. The analytical solutions to the adjoint equations are also constructed via Green's function approach for the purpose of comparing the numerical results. The pressure-matching inverse design is then conducted for a nozzle parameterized by a single geometric parameter. In the second part, the adjoint methods are applied to the problem of minimizing drag coefficient, at fixed lift coefficient, for 2-D transonic airfoil flows. Reduced gradients of several functionals are derived through application of a Lagrange Multiplier Theorem. The adjoint system is carefully studied including the adjoint characteristic boundary conditions at the far-field boundary. A super-reduced design formulation is also explored by treating the angle of attack as an additional state; super-reduced gradients can be constructed either by solving adjoint equations with non-local boundary conditions or by a direct Lagrange multiplier method. In this way, the constrained optimization reduces to an unconstrained design problem. Numerical methods based on Jameson's finite volume scheme are employed to solve the adjoint equations. The same grid system generated from an efficient hyperbolic grid generator are adopted in both the Euler flow solver and the adjoint solver. Several

  13. Libration Orbit Mission Design: Applications of Numerical & Dynamical Methods

    NASA Technical Reports Server (NTRS)

    Bauer, Frank (Technical Monitor); Folta, David; Beckman, Mark

    2002-01-01

    Sun-Earth libration point orbits serve as excellent locations for scientific investigations. These orbits are often selected to minimize environmental disturbances and maximize observing efficiency. Trajectory design in support of libration orbits is ever more challenging as more complex missions are envisioned in the next decade. Trajectory design software must be further enabled to incorporate better understanding of the libration orbit solution space and thus improve the efficiency and expand the capabilities of current approaches. The Goddard Space Flight Center (GSFC) is currently supporting multiple libration missions. This end-to-end support consists of mission operations, trajectory design, and control. It also includes algorithm and software development. The recently launched Microwave Anisotropy Probe (MAP) and upcoming James Webb Space Telescope (JWST) and Constellation-X missions are examples of the use of improved numerical methods for attaining constrained orbital parameters and controlling their dynamical evolution at the collinear libration points. This paper presents a history of libration point missions, a brief description of the numerical and dynamical design techniques including software used, and a sample of future GSFC mission designs.

  14. Development of quality-by-design analytical methods.

    PubMed

    Vogt, Frederick G; Kord, Alireza S

    2011-03-01

    Quality-by-design (QbD) is a systematic approach to drug development, which begins with predefined objectives, and uses science and risk management approaches to gain product and process understanding and ultimately process control. The concept of QbD can be extended to analytical methods. QbD mandates the definition of a goal for the method, and emphasizes thorough evaluation and scouting of alternative methods in a systematic way to obtain optimal method performance. Candidate methods are then carefully assessed in a structured manner for risks, and are challenged to determine if robustness and ruggedness criteria are satisfied. As a result of these studies, the method performance can be understood and improved if necessary, and a control strategy can be defined to manage risk and ensure the method performs as desired when validated and deployed. In this review, the current state of analytical QbD in the industry is detailed with examples of the application of analytical QbD principles to a range of analytical methods, including high-performance liquid chromatography, Karl Fischer titration for moisture content, vibrational spectroscopy for chemical identification, quantitative color measurement, and trace analysis for genotoxic impurities.

  15. Towards Robust Designs Via Multiple-Objective Optimization Methods

    NASA Technical Reports Server (NTRS)

    Man Mohan, Rai

    2006-01-01

    evolutionary method (DE) is first used to solve a relatively difficult problem in extended surface heat transfer wherein optimal fin geometries are obtained for different safe operating base temperatures. The objective of maximizing the safe operating base temperature range is in direct conflict with the objective of maximizing fin heat transfer. This problem is a good example of achieving robustness in the context of changing operating conditions. The evolutionary method is then used to design a turbine airfoil; the two objectives being reduced sensitivity of the pressure distribution to small changes in the airfoil shape and the maximization of the trailing edge wedge angle with the consequent increase in airfoil thickness and strength. This is a relevant example of achieving robustness to manufacturing tolerances and wear and tear in the presence of other objectives.

  16. Risk-informed regulation and safety management of nuclear power plants--on the prevention of severe accidents.

    PubMed

    Himanen, Risto; Julin, Ari; Jänkälä, Kalle; Holmberg, Jan-Erik; Virolainen, Reino

    2012-11-01

    There are four operating nuclear power plant (NPP) units in Finland. The Teollisuuden Voima (TVO) power company has two 840 MWe BWR units supplied by Asea-Atom at the Olkiluoto site. The Fortum corporation (formerly IVO) has two 500 MWe VVER 440/213 units at the Loviisa site. In addition, a 1600 MWe European Pressurized Water Reactor supplied by AREVA NP (formerly the Framatome ANP--Siemens AG Consortium) is under construction at the Olkiluoto site. Recently, the Finnish Parliament ratified the government Decision in Principle that the utilities' applications to build two new NPP units are in line with the total good of the society. The Finnish utilities, Fenno power company, and TVO company are in progress of qualifying the type of the new nuclear builds. In Finland, risk-informed applications are formally integrated in the regulatory process of NPPs that are already in the early design phase and these are to run through the construction and operation phases all through the entire plant service time. A plant-specific full-scope probabilistic risk assessment (PRA) is required for each NPP. PRAs shall cover internal events, area events (fires, floods), and external events such as harsh weather conditions and seismic events in all operating modes. Special attention is devoted to the use of various risk-informed PRA applications in the licensing of Olkiluoto 3 NPP.

  17. Examining trust factors in online food risk information: The case of unpasteurized or 'raw' milk.

    PubMed

    Sillence, Elizabeth; Hardy, Claire; Medeiros, Lydia C; LeJeune, Jeffrey T

    2016-04-01

    The internet has become an increasingly important way of communicating with consumers about food risk information. However, relatively little is known about how consumers evaluate and come to trust the information they encounter online. Using the example of unpasteurized or raw milk this paper presents two studies exploring the trust factors associated with online information about the risks and benefits of raw milk consumption. In the first study, eye-tracking data was collected from 33 pasteurised milk consumers whilst they viewed six different milk related websites. A descriptive analysis of the eye-tracking data was conducted to explore viewing patterns. Reports revealed the importance of images as a way of capturing initial attention and foregrounding other features and highlighted the significance of introductory text within a homepage. In the second, qualitative study, 41 consumers, some of whom drank raw milk, viewed a selection of milk related websites before participating in either a group discussion or interview. Seventeen of the participants also took part in a follow up telephone interview 2 weeks later. The qualitative data supports the importance of good design whilst noting that balance, authorship agenda, the nature of evidence and personal relevance were also key factors affecting consumers trust judgements. The results of both studies provide support for a staged approach to online trust in which consumers engage in a more rapid, heuristic assessment of a site before moving on to a more in-depth evaluation of the information available. Findings are discussed in relation to the development of trustworthy online food safety resources.

  18. Bayesian methods for the design and analysis of noninferiority trials.

    PubMed

    Gamalo-Siebers, Margaret; Gao, Aijun; Lakshminarayanan, Mani; Liu, Guanghan; Natanegara, Fanni; Railkar, Radha; Schmidli, Heinz; Song, Guochen

    2016-01-01

    The gold standard for evaluating treatment efficacy of a medical product is a placebo-controlled trial. However, when the use of placebo is considered to be unethical or impractical, a viable alternative for evaluating treatment efficacy is through a noninferiority (NI) study where a test treatment is compared to an active control treatment. The minimal objective of such a study is to determine whether the test treatment is superior to placebo. An assumption is made that if the active control treatment remains efficacious, as was observed when it was compared against placebo, then a test treatment that has comparable efficacy with the active control, within a certain range, must also be superior to placebo. Because of this assumption, the design, implementation, and analysis of NI trials present challenges for sponsors and regulators. In designing and analyzing NI trials, substantial historical data are often required on the active control treatment and placebo. Bayesian approaches provide a natural framework for synthesizing the historical data in the form of prior distributions that can effectively be used in design and analysis of a NI clinical trial. Despite a flurry of recent research activities in the area of Bayesian approaches in medical product development, there are still substantial gaps in recognition and acceptance of Bayesian approaches in NI trial design and analysis. The Bayesian Scientific Working Group of the Drug Information Association provides a coordinated effort to target the education and implementation issues on Bayesian approaches for NI trials. In this article, we provide a review of both frequentist and Bayesian approaches in NI trials, and elaborate on the implementation for two common Bayesian methods including hierarchical prior method and meta-analytic-predictive approach. Simulations are conducted to investigate the properties of the Bayesian methods, and some real clinical trial examples are presented for illustration.

  19. Analytical methods for gravity-assist tour design

    NASA Astrophysics Data System (ADS)

    Strange, Nathan J.

    This dissertation develops analytical methods for the design of gravity-assist space- craft trajectories. Such trajectories are commonly employed by planetary science missions to reach Mercury or the Outer Planets. They may also be used at the Outer Planets for the design of science tours with multiple flybys of those planets' moons. Recent work has also shown applicability to new missions concepts such as NASA's Asteroid Redirect Mission. This work is based in the theory of patched conics. This document applies rigor to the concept of pumping (i.e. using gravity assists to change orbital energy) and cranking (i.e. using gravity assists to change inclination) to develop several analytic relations with pump and crank angles. In addition, transformations are developed between pump angle, crank angle, and v-infinity magnitude to classical orbit elements. These transformations are then used to describe the limits on orbits achievable via gravity assists of a planet or moon. This is then extended to develop analytic relations for all possible ballistic gravity-assist transfers and one type of propulsive transfer, v-infinity leveraging transfers. The results in this dissertation complement existing numerical methods for the design of these trajectories by providing methods that can guide numerical searches to find promising trajectories and even, in some cases, replace numerical searches altogether. In addition, results from new techniques presented in this dissertation such as Tisserand Graphs, the V-Infinity Globe, and Non-Tangent V-Infinty Leveraging provide additional insight into the structure of the gravity-assist trajectory design problem.

  20. Treatment of Passive Component Reliability in Risk-Informed Safety Margin Characterization FY 2010 Report

    SciTech Connect

    Robert W Youngblood

    2010-09-01

    The Risk-Informed Safety Margin Characterization (RISMC) pathway is a set of activities defined under the U.S. Department of Energy (DOE) Light Water Reactor Sustainability Program. The overarching objective of RISMC is to support plant life-extension decision-making by providing a state-of-knowledge characterization of safety margins in key systems, structures, and components (SSCs). A technical challenge at the core of this effort is to establish the conceptual and technical feasibility of analyzing safety margin in a risk-informed way, which, unlike conventionally defined deterministic margin analysis, is founded on probabilistic characterizations of SSC performance.

  1. Improved Method of Design for Folding Inflatable Shells

    NASA Technical Reports Server (NTRS)

    Johnson, Christopher J.

    2009-01-01

    An improved method of designing complexly shaped inflatable shells to be assembled from gores was conceived for original application to the inflatable outer shell of a developmental habitable spacecraft module having a cylindrical mid-length section with toroidal end caps. The method is also applicable to inflatable shells of various shapes for terrestrial use. The method addresses problems associated with the assembly, folding, transport, and deployment of inflatable shells that may comprise multiple layers and have complex shapes that can include such doubly curved surfaces as toroids and spheres. One particularly difficult problem is that of mathematically defining fold lines on a gore pattern in a double- curvature region. Moreover, because the fold lines in a double-curvature region tend to be curved, there is a practical problem of how to implement the folds. Another problem is that of modifying the basic gore shapes and sizes for the various layers so that when they are folded as part of the integral structure, they do not mechanically interfere with each other at the fold lines. Heretofore, it has been a common practice to design an inflatable shell to be assembled in the deployed configuration, without regard for the need to fold it into compact form. Typically, the result has been that folding has been a difficult, time-consuming process resulting in a An improved method of designing complexly shaped inflatable shells to be assembled from gores was conceived for original application to the inflatable outer shell of a developmental habitable spacecraft module having a cylindrical mid-length section with toroidal end caps. The method is also applicable to inflatable shells of various shapes for terrestrial use. The method addresses problems associated with the assembly, folding, transport, and deployment of inflatable shells that may comprise multiple layers and have complex shapes that can include such doubly curved surfaces as toroids and spheres. One

  2. Measuring the design of empathetic buildings: a review of universal design evaluation methods.

    PubMed

    O Shea, Eoghan Conor; Pavia, Sara; Dyer, Mark; Craddock, Gerald; Murphy, Neil

    2016-01-01

    Universal design (UD) provides an explanation of good design based on the user perspective, which are outlined through its principles, goals, and related frameworks. The aim of this paper is to provide an overview of the frameworks and methods for UD building evaluations and to describe how close they have come to describing what a universally designed building is. Evaluation approaches are reviewed from the existing literature across a number of spatial disciplines, including UD, human geography and urban studies. Four categories of UD evaluation methods are outlined, including (1) checklist evaluations, (2) value-driven evaluations, (3) holistic evaluations, and (4) invisible evaluations. A number of suggestions are made to aid research aimed at developing UD evaluation in buildings. (1) Design standards and guidelines should be contested or validated where possible; (2) evaluation criteria should be contextual; (3) it may be more practical to have separate methodologies for contextualising UD to allow for the creation of an evaluating tool that is practical in use. Additionally, there is a difficulty in establishing a clear basis for evaluating how empathetic buildings are without expanding the methodological horizons of UD evaluation. Implications for Rehabilitation For universal design (UD) evaluation to address human need requires methods that are culturally, temporally, and typologically specific. Practical instruments for measuring UD need to be divorced from but contingent upon methods than can address local specificities. The process of evaluation can provide knowledge that can contest or validate the literature based sources such as design guidelines, or standards. UD evaluation requires constant renewal by searching for new, flexible strategies that can respond to socio-cultural change.

  3. An experimental design method leading to chemical Turing patterns.

    PubMed

    Horváth, Judit; Szalai, István; De Kepper, Patrick

    2009-05-08

    Chemical reaction-diffusion patterns often serve as prototypes for pattern formation in living systems, but only two isothermal single-phase reaction systems have produced sustained stationary reaction-diffusion patterns so far. We designed an experimental method to search for additional systems on the basis of three steps: (i) generate spatial bistability by operating autoactivated reactions in open spatial reactors; (ii) use an independent negative-feedback species to produce spatiotemporal oscillations; and (iii) induce a space-scale separation of the activatory and inhibitory processes with a low-mobility complexing agent. We successfully applied this method to a hydrogen-ion autoactivated reaction, the thiourea-iodate-sulfite (TuIS) reaction, and noticeably produced stationary hexagonal arrays of spots and parallel stripes of pH patterns attributed to a Turing bifurcation. This method could be extended to biochemical reactions.

  4. Design of time interval generator based on hybrid counting method

    NASA Astrophysics Data System (ADS)

    Yao, Yuan; Wang, Zhaoqi; Lu, Houbing; Chen, Lian; Jin, Ge

    2016-10-01

    Time Interval Generators (TIGs) are frequently used for the characterizations or timing operations of instruments in particle physics experiments. Though some "off-the-shelf" TIGs can be employed, the necessity of a custom test system or control system makes the TIGs, being implemented in a programmable device desirable. Nowadays, the feasibility of using Field Programmable Gate Arrays (FPGAs) to implement particle physics instrumentation has been validated in the design of Time-to-Digital Converters (TDCs) for precise time measurement. The FPGA-TDC technique is based on the architectures of Tapped Delay Line (TDL), whose delay cells are down to few tens of picosecond. In this case, FPGA-based TIGs with high delay step are preferable allowing the implementation of customized particle physics instrumentations and other utilities on the same FPGA device. A hybrid counting method for designing TIGs with both high resolution and wide range is presented in this paper. The combination of two different counting methods realizing an integratable TIG is described in detail. A specially designed multiplexer for tap selection is emphatically introduced. The special structure of the multiplexer is devised for minimizing the different additional delays caused by the unpredictable routings from different taps to the output. A Kintex-7 FPGA is used for the hybrid counting-based implementation of a TIG, providing a resolution up to 11 ps and an interval range up to 8 s.

  5. Sequence design in lattice models by graph theoretical methods

    NASA Astrophysics Data System (ADS)

    Sanjeev, B. S.; Patra, S. M.; Vishveshwara, S.

    2001-01-01

    A general strategy has been developed based on graph theoretical methods, for finding amino acid sequences that take up a desired conformation as the native state. This problem of inverse design has been addressed by assigning topological indices for the monomer sites (vertices) of the polymer on a 3×3×3 cubic lattice. This is a simple design strategy, which takes into account only the topology of the target protein and identifies the best sequence for a given composition. The procedure allows the design of a good sequence for a target native state by assigning weights for the vertices on a lattice site in a given conformation. It is seen across a variety of conformations that the predicted sequences perform well both in sequence and in conformation space, in identifying the target conformation as native state for a fixed composition of amino acids. Although the method is tested in the framework of the HP model [K. F. Lau and K. A. Dill, Macromolecules 22, 3986 (1989)] it can be used in any context if proper potential functions are available, since the procedure derives unique weights for all the sites (vertices, nodes) of the polymer chain of a chosen conformation (graph).

  6. Designing A Mixed Methods Study In Primary Care

    PubMed Central

    Creswell, John W.; Fetters, Michael D.; Ivankova, Nataliya V.

    2004-01-01

    BACKGROUND Mixed methods or multimethod research holds potential for rigorous, methodologically sound investigations in primary care. The objective of this study was to use criteria from the literature to evaluate 5 mixed methods studies in primary care and to advance 3 models useful for designing such investigations. METHODS We first identified criteria from the social and behavioral sciences to analyze mixed methods studies in primary care research. We then used the criteria to evaluate 5 mixed methods investigations published in primary care research journals. RESULTS Of the 5 studies analyzed, 3 included a rationale for mixing based on the need to develop a quantitative instrument from qualitative data or to converge information to best understand the research topic. Quantitative data collection involved structured interviews, observational checklists, and chart audits that were analyzed using descriptive and inferential statistical procedures. Qualitative data consisted of semistructured interviews and field observations that were analyzed using coding to develop themes and categories. The studies showed diverse forms of priority: equal priority, qualitative priority, and quantitative priority. Data collection involved quantitative and qualitative data gathered both concurrently and sequentially. The integration of the quantitative and qualitative data in these studies occurred between data analysis from one phase and data collection from a subsequent phase, while analyzing the data, and when reporting the results. DISCUSSION We recommend instrument-building, triangulation, and data transformation models for mixed methods designs as useful frameworks to add rigor to investigations in primary care. We also discuss the limitations of our study and the need for future research. PMID:15053277

  7. Modified method to improve the design of Petlyuk distillation columns

    PubMed Central

    2014-01-01

    Background A response surface analysis was performed to study the effect of the composition and feeding thermal conditions of ternary mixtures on the number of theoretical stages and the energy consumption of Petlyuk columns. A modification of the pre-design algorithm was necessary for this purpose. Results The modified algorithm provided feasible results in 100% of the studied cases, compared with only 8.89% for the current algorithm. The proposed algorithm allowed us to attain the desired separations, despite the type of mixture and the operating conditions in the feed stream, something that was not possible with the traditional pre-design method. The results showed that the type of mixture had great influence on the number of stages and on energy consumption. A higher number of stages and a lower consumption of energy were attained with mixtures rich in the light component, while higher energy consumption occurred when the mixture was rich in the heavy component. Conclusions The proposed strategy expands the search of an optimal design of Petlyuk columns within a feasible region, which allow us to find a feasible design that meets output specifications and low thermal loads. PMID:25061476

  8. Modified method to improve the design of Petlyuk distillation columns.

    PubMed

    Zapiain-Salinas, Javier G; Barajas-Fernández, Juan; González-García, Raúl

    2014-01-01

    A response surface analysis was performed to study the effect of the composition and feeding thermal conditions of ternary mixtures on the number of theoretical stages and the energy consumption of Petlyuk columns. A modification of the pre-design algorithm was necessary for this purpose. The modified algorithm provided feasible results in 100% of the studied cases, compared with only 8.89% for the current algorithm. The proposed algorithm allowed us to attain the desired separations, despite the type of mixture and the operating conditions in the feed stream, something that was not possible with the traditional pre-design method. The results showed that the type of mixture had great influence on the number of stages and on energy consumption. A higher number of stages and a lower consumption of energy were attained with mixtures rich in the light component, while higher energy consumption occurred when the mixture was rich in the heavy component. The proposed strategy expands the search of an optimal design of Petlyuk columns within a feasible region, which allow us to find a feasible design that meets output specifications and low thermal loads.

  9. A Probabilistic Design Method Applied to Smart Composite Structures

    NASA Technical Reports Server (NTRS)

    Shiao, Michael C.; Chamis, Christos C.

    1995-01-01

    A probabilistic design method is described and demonstrated using a smart composite wing. Probabilistic structural design incorporates naturally occurring uncertainties including those in constituent (fiber/matrix) material properties, fabrication variables, structure geometry and control-related parameters. Probabilistic sensitivity factors are computed to identify those parameters that have a great influence on a specific structural reliability. Two performance criteria are used to demonstrate this design methodology. The first criterion requires that the actuated angle at the wing tip be bounded by upper and lower limits at a specified reliability. The second criterion requires that the probability of ply damage due to random impact load be smaller than an assigned value. When the relationship between reliability improvement and the sensitivity factors is assessed, the results show that a reduction in the scatter of the random variable with the largest sensitivity factor (absolute value) provides the lowest failure probability. An increase in the mean of the random variable with a negative sensitivity factor will reduce the failure probability. Therefore, the design can be improved by controlling or selecting distribution parameters associated with random variables. This can be implemented during the manufacturing process to obtain maximum benefit with minimum alterations.

  10. Rapid and simple method of qPCR primer design.

    PubMed

    Thornton, Brenda; Basu, Chhandak

    2015-01-01

    Quantitative real-time polymerase chain reaction (qPCR) is a powerful tool for analysis and quantification of gene expression. It is advantageous compared to traditional gel-based method of PCR, as gene expression can be visualized "real-time" using a computer. In qPCR, a reporter dye system is used which intercalates with DNA's region of interest and detects DNA amplification. Some of the popular reporter systems used in qPCR are the following: Molecular Beacon(®), SYBR Green(®), and Taqman(®). However, success of qPCR depends on the optimal primers used. Some of the considerations for primer design are the following: GC content, primer self-dimer, or secondary structure formation. Freely available software could be used for ideal qPCR primer design. Here we have shown how to use some freely available web-based software programs (such as Primerquest(®), Unafold(®), and Beacon designer(®)) to design qPCR primers.

  11. A geometric method for optimal design of color filter arrays.

    PubMed

    Hao, Pengwei; Li, Yan; Lin, Zhouchen; Dubois, Eric

    2011-03-01

    A color filter array (CFA) used in a digital camera is a mosaic of spectrally selective filters, which allows only one color component to be sensed at each pixel. The missing two components of each pixel have to be estimated by methods known as demosaicking. The demosaicking algorithm and the CFA design are crucial for the quality of the output images. In this paper, we present a CFA design methodology in the frequency domain. The frequency structure, which is shown to be just the symbolic DFT of the CFA pattern (one period of the CFA), is introduced to represent images sampled with any rectangular CFAs in the frequency domain. Based on the frequency structure, the CFA design involves the solution of a constrained optimization problem that aims at minimizing the demosaicking error. To decrease the number of parameters and speed up the parameter searching, the optimization problem is reformulated as the selection of geometric points on the boundary of a convex polygon or the surface of a convex polyhedron. Using our methodology, several new CFA patterns are found, which outperform the currently commercialized and published ones. Experiments demonstrate the effectiveness of our CFA design methodology and the superiority of our new CFA patterns.

  12. Optimization design of thumbspica splint using finite element method.

    PubMed

    Huang, Tz-How; Feng, Chi-Kung; Gung, Yih-Wen; Tsai, Mei-Wun; Chen, Chen-Sheng; Liu, Chien-Lin

    2006-12-01

    De Quervain's tenosynovitis is often observed on repetitive flexion of the thumb. In the clinical setting, the conservative treatment is usually an applied thumbspica splint to immobilize the thumb. However, the traditional thumbspica splint is bulky and heavy. Thus, this study used the finite element (FE) method to remove redundant material in order to reduce the splint's weight and increase ventilation. An FE model of a thumbspica splint was constructed using ANSYS9.0 software. A maximum lateral thumb pinch force of 98 N was used as the input loading condition for the FE model. This study implemented topology optimization and design optimization to seek the optimal thickness and shape of the splint. This new design was manufactured and compared with the traditional thumbspica splint. Ten thumbspica splints were tested in a materials testing system, and statistically analyzed using an independent t test. The optimal thickness of the thumbspica splint was 3.2 mm. The new design is not significantly different from the traditional splint in the immobilization effect. However, the volume of this new design has been reduced by about 35%. This study produced a new thumbspica splint shape with less volume, but had a similar immobilization effect compared to the traditional shape. In a clinical setting, this result can be used by the occupational therapist as a reference for manufacturing lighter thumbspica splints for patients with de Quervain's tenosynovitis.

  13. Optimal experimental design with the sigma point method.

    PubMed

    Schenkendorf, R; Kremling, A; Mangold, M

    2009-01-01

    Using mathematical models for a quantitative description of dynamical systems requires the identification of uncertain parameters by minimising the difference between simulation and measurement. Owing to the measurement noise also, the estimated parameters possess an uncertainty expressed by their variances. To obtain highly predictive models, very precise parameters are needed. The optimal experimental design (OED) as a numerical optimisation method is used to reduce the parameter uncertainty by minimising the parameter variances iteratively. A frequently applied method to define a cost function for OED is based on the inverse of the Fisher information matrix. The application of this traditional method has at least two shortcomings for models that are nonlinear in their parameters: (i) it gives only a lower bound of the parameter variances and (ii) the bias of the estimator is neglected. Here, the authors show that by applying the sigma point (SP) method a better approximation of characteristic values of the parameter statistics can be obtained, which has a direct benefit on OED. An additional advantage of the SP method is that it can also be used to investigate the influence of the parameter uncertainties on the simulation results. The SP method is demonstrated for the example of a widely used biological model.

  14. Risk-Informed Safety Margin Characterization Case Study: Selection of Electrical Equipment to Be Subjected to Environmental Qualification

    SciTech Connect

    D. P. Blanchard; R. W. Youngblood

    2014-06-01

    The Risk-Informed Safety Margin Characterization (RISMC) pathway of the DOE’s Light Water Reactor Sustainability (LWRS) program focuses on advancing the state of the art in safety analysis and risk assessment to support decision-making on nuclear power plant operation well beyond the originally designed lifetime of the plants (i.e., beyond 60 years). Among the issues being addressed in RISMC is the significance of SSC aging and how confident we are about our understanding of its impact on the margin between the loads SSCs are expected to see during normal operation and accident conditions, and the SSC capacities (their ability to resist those loads) as the SSCs age. In this paper, a summary is provided of a case study that examines SSC aging from an environmental qualification (EQ) perspective. The case study illustrates how the state of knowledge regarding SSC margin can be characterized given the overall integrated plant design, and was developed to demonstrate a method for deciding on which cables to focus, which cables are not so important from an environmental qualification margin standpoint, and what plant design features or operating characteristics determine the role that environmental qualification plays in establishing a safety case on which decisions regarding margin can be made. The selection of cables for which demonstration of margin with respect to aging and environmental challenges uses a technique known as Prevention Analysis. Prevention Analysis is a Boolean method for optimal selection of SSCs (that is, those combinations of SSCs both necessary and sufficient to meet a predetermined selection criterion) in a manner that allows demonstration that plant-level safety can be demonstrated by the collection of selected SSCs alone. Choosing the set of SSCs that is necessary and sufficient to satisfy the safety objectives, and demonstrating that the safety objectives can be met effectively, determines where resources are best allocated to assure SSC

  15. Statistical Methods for Rapid Aerothermal Analysis and Design Technology: Validation

    NASA Technical Reports Server (NTRS)

    DePriest, Douglas; Morgan, Carolyn

    2003-01-01

    The cost and safety goals for NASA s next generation of reusable launch vehicle (RLV) will require that rapid high-fidelity aerothermodynamic design tools be used early in the design cycle. To meet these requirements, it is desirable to identify adequate statistical models that quantify and improve the accuracy, extend the applicability, and enable combined analyses using existing prediction tools. The initial research work focused on establishing suitable candidate models for these purposes. The second phase is focused on assessing the performance of these models to accurately predict the heat rate for a given candidate data set. This validation work compared models and methods that may be useful in predicting the heat rate.

  16. A new method for designing shock-free transonic configurations

    NASA Technical Reports Server (NTRS)

    Sobieczky, H.; Fung, K. Y.; Seebass, A. R.; Yu, N. J.

    1978-01-01

    A method for the design of shock free supercritical airfoils, wings, and three dimensional configurations is described. Results illustrating the procedure in two and three dimensions are given. They include modifications to part of the upper surface of an NACA 64A410 airfoil that will maintain shock free flow over a range of Mach numbers for a fixed lift coefficient, and the modifications required on part of the upper surface of a swept wing with an NACA 64A410 root section to achieve shock free flow. While the results are given for inviscid flow, the same procedures can be employed iteratively with a boundary layer calculation in order to achieve shock free viscous designs. With a shock free pressure field the boundary layer calculation will be reliable and not complicated by the difficulties of shock wave boundary layer interaction.

  17. A Method for Designing CDO Conformed to Investment Parameters

    NASA Astrophysics Data System (ADS)

    Nakae, Tatsuya; Moritsu, Toshiyuki; Komoda, Norihisa

    We propose a method for designing CDO (Collateralized Debt Obligation) that meets investor needs about attributes of CDO. It is demonstrated that adjusting attributes (that are credit capability and issue amount) of CDO to investors' preferences causes a capital loss risk that the agent takes. We formulate a CDO optimization problem by defining an objective function using the above risk and by setting constraints that arise from investor needs and a risk premium that is paid for the agent. Our prototype experiment, in which fictitious underlying obligations and investor needs are given, verifies that CDOs can be designed without opportunity loss and dead stock loss, and that the capital loss is not more than thousandth part of the amount of annual payment under guarantee for small and midium-sized enterprises by a general credit guarantee institution.

  18. A Generic Method for Design of Oligomer-Specific Antibodies

    PubMed Central

    Brännström, Kristoffer; Lindhagen-Persson, Malin; Gharibyan, Anna L.; Iakovleva, Irina; Vestling, Monika; Sellin, Mikael E.; Brännström, Thomas; Morozova-Roche, Ludmilla; Forsgren, Lars; Olofsson, Anders

    2014-01-01

    Antibodies that preferentially and specifically target pathological oligomeric protein and peptide assemblies, as opposed to their monomeric and amyloid counterparts, provide therapeutic and diagnostic opportunities for protein misfolding diseases. Unfortunately, the molecular properties associated with oligomer-specific antibodies are not well understood, and this limits targeted design and development. We present here a generic method that enables the design and optimisation of oligomer-specific antibodies. The method takes a two-step approach where discrimination between oligomers and fibrils is first accomplished through identification of cryptic epitopes exclusively buried within the structure of the fibrillar form. The second step discriminates between monomers and oligomers based on differences in avidity. We show here that a simple divalent mode of interaction, as within e.g. the IgG isotype, can increase the binding strength of the antibody up to 1500 times compared to its monovalent counterpart. We expose how the ability to bind oligomers is affected by the monovalent affinity and the turnover rate of the binding and, importantly, also how oligomer specificity is only valid within a specific concentration range. We provide an example of the method by creating and characterising a spectrum of different monoclonal antibodies against both the Aβ peptide and α-synuclein that are associated with Alzheimer's and Parkinson's diseases, respectively. The approach is however generic, does not require identification of oligomer-specific architectures, and is, in essence, applicable to all polypeptides that form oligomeric and fibrillar assemblies. PMID:24618582

  19. Design and implementation of visualization methods for the CHANGES Spatial Decision Support System

    NASA Astrophysics Data System (ADS)

    Cristal, Irina; van Westen, Cees; Bakker, Wim; Greiving, Stefan

    2014-05-01

    The CHANGES Spatial Decision Support System (SDSS) is a web-based system aimed for risk assessment and the evaluation of optimal risk reduction alternatives at local level as a decision support tool in long-term natural risk management. The SDSS use multidimensional information, integrating thematic, spatial, temporal and documentary data. The role of visualization in this context becomes of vital importance for efficiently representing each dimension. This multidimensional aspect of the required for the system risk information, combined with the diversity of the end-users imposes the use of sophisticated visualization methods and tools. The key goal of the present work is to exploit efficiently the large amount of data in relation to the needs of the end-user, utilizing proper visualization techniques. Three main tasks have been accomplished for this purpose: categorization of the end-users, the definition of system's modules and the data definition. The graphical representation of the data and the visualization tools were designed to be relevant to the data type and the purpose of the analysis. Depending on the end-users category, each user should have access to different modules of the system and thus, to the proper visualization environment. The technologies used for the development of the visualization component combine the latest and most innovative open source JavaScript frameworks, such as OpenLayers 2.13.1, ExtJS 4 and GeoExt 2. Moreover, the model-view-controller (MVC) pattern is used in order to ensure flexibility of the system at the implementation level. Using the above technologies, the visualization techniques implemented so far offer interactive map navigation, querying and comparison tools. The map comparison tools are of great importance within the SDSS and include the following: swiping tool for comparison of different data of the same location; raster subtraction for comparison of the same phenomena varying in time; linked views for comparison

  20. Design of braided composite tubes by numerical analysis method

    SciTech Connect

    Hamada, Hiroyuki; Fujita, Akihiro; Maekawa, Zenichiro; Nakai, Asami; Yokoyama, Atsushi

    1995-11-01

    Conventional composite laminates have very poor strength through thickness and as a result are limited in their application for structural parts with complex shape. In this paper, the design for braided composite tube was proposed. The concept of analysis model which involved from micro model to macro model was presented. This method was applied to predict bending rigidity and initial fracture stress under bending load of the braided tube. The proposed analytical procedure can be included as a unit in CAE system for braided composites.

  1. Methods to Design and Synthesize Antibody-Drug Conjugates (ADCs)

    PubMed Central

    Yao, Houzong; Jiang, Feng; Lu, Aiping; Zhang, Ge

    2016-01-01

    Antibody-drug conjugates (ADCs) have become a promising targeted therapy strategy that combines the specificity, favorable pharmacokinetics and biodistributions of antibodies with the destructive potential of highly potent drugs. One of the biggest challenges in the development of ADCs is the application of suitable linkers for conjugating drugs to antibodies. Recently, the design and synthesis of linkers are making great progress. In this review, we present the methods that are currently used to synthesize antibody-drug conjugates by using thiols, amines, alcohols, aldehydes and azides. PMID:26848651

  2. Comparison of Optimal Design Methods in Inverse Problems

    DTIC Science & Technology

    2011-05-11

    corresponding FIM can be estimated by F̂ (τ) = F̂ (τ, θ̂OLS) = (Σ̂ N (θ̂OLS)) −1. (13) The asymptotic standard errors are given by SEk (θ0) = √ (ΣN0 )kk, k...1, . . . , p. (14) These standard errors are estimated in practice (when θ0 and σ0 are not known) by SEk (θ̂OLS) = √ (Σ̂N (θ̂OLS))kk, k = 1... SEk (θ̂boot) = √ Cov(θ̂boot)kk. We will compare the optimal design methods using the standard errors resulting from the op- timal time points each

  3. Fault Management in an Objectives-Based/Risk-Informed View of Safety and Mission Success

    NASA Technical Reports Server (NTRS)

    Groen, Frank

    2012-01-01

    Theme of this talk: (1) Net-benefit of activities and decisions derives from objectives (and their priority) -- similarly: need for integration, value of technology/capability. (2) Risk is a lack of confidence that objectives will be met. (2a) Risk-informed decision making requires objectives. (3) Consideration of objectives is central to recent guidance.

  4. DSSTox EPA Integrated Risk Information System Structure-Index Locator File: SDF File and Documentation

    EPA Science Inventory

    EPA's Integrated Risk Information System (IRIS) database was developed and is maintained by EPA's Office of Research and Developement, National Center for Environmental Assessment. IRIS is a database of human health effects that may result from exposure to various substances fou...

  5. 77 FR 41784 - Integrated Risk Information System (IRIS); Announcement of Availability of Literature Searches...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-16

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY Integrated Risk Information System (IRIS); Announcement of Availability of Literature Searches for... or email. The http://www.regulations.gov Web site is an ``anonymous access'' system, which means...

  6. 75 FR 76982 - Integrated Risk Information System (IRIS); Announcement of Availability of Literature Searches...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-10

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY Integrated Risk Information System (IRIS); Announcement of Availability of Literature Searches for... Web site is an ``anonymous access'' system, which means EPA will not know your identity or...

  7. 77 FR 20817 - Integrated Risk Information System (IRIS); Announcement of Availability of Literature Searches...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-06

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY Integrated Risk Information System (IRIS); Announcement of Availability of Literature Searches for....regulations.gov or email. The http://www.regulations.gov Web site is an ``anonymous access'' system,...

  8. CHARACTERIZATION OF DATA VARIABILITY AND UNCERTAINTY: HEALTH EFFECTS ASSESSMENTS IN THE INTEGRATED RISK INFORMATION SYSTEM (IRIS)

    EPA Science Inventory

    In response to a Congressional directive contained in HR 106-379 regarding EPA's appropriations for FY2000, EPA has undertaken an evaluation of the characterization of data variability and uncertainty in its Integrated Risk Information System (IRIS) health effects information dat...

  9. DSSTox EPA Integrated Risk Information System Structure-Index Locator File: SDF File and Documentation

    EPA Science Inventory

    EPA's Integrated Risk Information System (IRIS) database was developed and is maintained by EPA's Office of Research and Developement, National Center for Environmental Assessment. IRIS is a database of human health effects that may result from exposure to various substances fou...

  10. The Effect of Genetic Risk Information and Health Risk Assessment on Compliance with Preventive Behaviors.

    ERIC Educational Resources Information Center

    Bamberg, Richard; And Others

    1990-01-01

    Results from a study of 82 males provide no statistical support and limited encouragement that genetic risk information may motivate persons to make positive changes in preventive health behaviors. Health risk assessments were used to identify subjects at risk for coronary heart disease or lung cancer because of genetic factors. (IAH)

  11. Patients' resistance to risk information in genetic counseling for BRCA1/2.

    PubMed

    Gurmankin, Andrea D; Domchek, Susan; Stopfer, Jill; Fels, Christina; Armstrong, Katrina

    2005-03-14

    Risk information from health care providers is relevant to and used in nearly all medical decisions. Patients often misunderstand their risks, yet little is known about the risk perception that patients derive from risk communications with health care providers. This study examines patients' risk perceptions following communication with health care providers during genetic counseling about the risks of breast cancer and BRCA1/2 mutations. A prospective, longitudinal study was conducted from October 2002 to February 2004 of women who received genetic counseling. The women completed a survey before their counseling and a telephone interview in the week after the counseling. Main outcome measures included change from precounseling in risk perception and accuracy of postcounseling risk perception (relative to actual risk information communicated). A total of 108 women agreed to participate in the study. The women's postcounseling risk perceptions were significantly lower than their precounseling risk perceptions (breast cancer: 17%, P<.001; mutation: 13%, P<.001) but were significantly higher than the actual risk information communicated (breast cancer: 19%, P<.001; mutation: 24%, P<.001). Accuracy of breast cancer risk perception but not mutation risk perception was associated with precounseling worry (P = .04), even after adjusting for trait anxiety (P = .01). This research demonstrates patients' resistance to risk information. Inappropriately high risk perception derived from a risk communication with a health care provider can lead patients to make different, and potentially worse, medical decisions than they would with an accurate risk perception and to be unnecessarily distressed about their risk.

  12. The Effect of Genetic Risk Information and Health Risk Assessment on Compliance with Preventive Behaviors.

    ERIC Educational Resources Information Center

    Bamberg, Richard; And Others

    1990-01-01

    Results from a study of 82 males provide no statistical support and limited encouragement that genetic risk information may motivate persons to make positive changes in preventive health behaviors. Health risk assessments were used to identify subjects at risk for coronary heart disease or lung cancer because of genetic factors. (IAH)

  13. 76 FR 13402 - Integrated Risk Information System (IRIS); Announcement of Availability of Literature Searches...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-11

    ... Amphibole asbestos. EPA is requesting scientific information on health effects that may result from exposure to these chemical substances. EPA's IRIS is a human health assessment program that evaluates quantitative and qualitative risk information on effects that may result from exposure to specific chemical...

  14. CHARACTERIZATION OF DATA VARIABILITY AND UNCERTAINTY: HEALTH EFFECTS ASSESSMENTS IN THE INTEGRATED RISK INFORMATION SYSTEM (IRIS)

    EPA Science Inventory

    In response to a Congressional directive contained in HR 106-379 regarding EPA's appropriations for FY2000, EPA has undertaken an evaluation of the characterization of data variability and uncertainty in its Integrated Risk Information System (IRIS) health effects information dat...

  15. A Method of Trajectory Design for Manned Asteroids Exploration

    NASA Astrophysics Data System (ADS)

    Gan, Q. B.; Zhang, Y.; Zhu, Z. F.; Han, W. H.; Dong, X.

    2014-11-01

    A trajectory optimization method of the nuclear propulsion manned asteroids exploration is presented. In the case of launching between 2035 and 2065, based on the Lambert transfer orbit, the phases of departure from and return to the Earth are searched at first. Then the optimal flight trajectory in the feasible regions is selected by pruning the flight sequences. Setting the nuclear propulsion flight plan as propel-coast-propel, and taking the minimal mass of aircraft departure as the index, the nuclear propulsion flight trajectory is separately optimized using a hybrid method. With the initial value of the optimized local parameters of each three phases, the global parameters are jointedly optimized. At last, the minimal departure mass trajectory design result is given.

  16. A novel observer design method for neural mass models

    NASA Astrophysics Data System (ADS)

    Liu, Xian; Miao, Dong-Kai; Gao, Qing; Xu, Shi-Yun

    2015-09-01

    Neural mass models can simulate the generation of electroencephalography (EEG) signals with different rhythms, and therefore the observation of the states of these models plays a significant role in brain research. The structure of neural mass models is special in that they can be expressed as Lurie systems. The developed techniques in Lurie system theory are applicable to these models. We here provide a new observer design method for neural mass models by transforming these models and the corresponding error systems into nonlinear systems with Lurie form. The purpose is to establish appropriate conditions which ensure the convergence of the estimation error. The effectiveness of the proposed method is illustrated by numerical simulations. Project supported by the National Natural Science Foundation of China (Grant Nos. 61473245, 61004050, and 51207144).

  17. An FPGA-based heterogeneous image fusion system design method

    NASA Astrophysics Data System (ADS)

    Song, Le; Lin, Yu-chi; Chen, Yan-hua; Zhao, Mei-rong

    2011-08-01

    Taking the advantages of FPGA's low cost and compact structure, an FPGA-based heterogeneous image fusion platform is established in this study. Altera's Cyclone IV series FPGA is adopted as the core processor of the platform, and the visible light CCD camera and infrared thermal imager are used as the image-capturing device in order to obtain dualchannel heterogeneous video images. Tailor-made image fusion algorithms such as gray-scale weighted averaging, maximum selection and minimum selection methods are analyzed and compared. VHDL language and the synchronous design method are utilized to perform a reliable RTL-level description. Altera's Quartus II 9.0 software is applied to simulate and implement the algorithm modules. The contrast experiments of various fusion algorithms show that, preferably image quality of the heterogeneous image fusion can be obtained on top of the proposed system. The applied range of the different fusion algorithms is also discussed.

  18. Performance enhancement of a pump impeller using optimal design method

    NASA Astrophysics Data System (ADS)

    Jeon, Seok-Yun; Kim, Chul-Kyu; Lee, Sang-Moon; Yoon, Joon-Yong; Jang, Choon-Man

    2017-04-01

    This paper presents the performance evaluation of a regenerative pump to increase its efficiency using optimal design method. Two design parameters which define the shape of the pump impeller, are introduced and analyzed. Pump performance is evaluated by numerical simulation and design of experiments(DOE). To analyze three-dimensional flow field in the pump, general analysis code, CFX, is used in the present work. Shear stress turbulence model is employed to estimate the eddy viscosity. Experimental apparatus with an open-loop facility is set up for measuring the pump performance. Pump performance, efficiency and pressure, obtained from numerical simulation are validated by comparison with the results of experiments. Throughout the shape optimization of the pump impeller at the operating flow condition, the pump efficiency is successfully increased by 3 percent compared to the reference pump. It is noted that the pressure increase of the optimum pump is mainly caused by higher momentum force generated inside blade passage due to the optimal blade shape. Comparisons of pump internal flow on the reference and optimum pump are also investigated and discussed in detail.

  19. Sensitivity method for integrated structure/active control law design

    NASA Technical Reports Server (NTRS)

    Gilbert, Michael G.

    1987-01-01

    The development is described of an integrated structure/active control law design methodology for aeroelastic aircraft applications. A short motivating introduction to aeroservoelasticity is given along with the need for integrated structures/controls design algorithms. Three alternative approaches to development of an integrated design method are briefly discussed with regards to complexity, coordination and tradeoff strategies, and the nature of the resulting solutions. This leads to the formulation of the proposed approach which is based on the concepts of sensitivity of optimum solutions and multi-level decompositions. The concept of sensitivity of optimum is explained in more detail and compared with traditional sensitivity concepts of classical control theory. The analytical sensitivity expressions for the solution of the linear, quadratic cost, Gaussian (LQG) control problem are summarized in terms of the linear regulator solution and the Kalman Filter solution. Numerical results for a state space aeroelastic model of the DAST ARW-II vehicle are given, showing the changes in aircraft responses to variations of a structural parameter, in this case first wing bending natural frequency.

  20. Novel computational methods to design protein-protein interactions

    NASA Astrophysics Data System (ADS)

    Zhou, Alice Qinhua; O'Hern, Corey; Regan, Lynne

    2014-03-01

    Despite the abundance of structural data, we still cannot accurately predict the structural and energetic changes resulting from mutations at protein interfaces. The inadequacy of current computational approaches to the analysis and design of protein-protein interactions has hampered the development of novel therapeutic and diagnostic agents. In this work, we apply a simple physical model that includes only a minimal set of geometrical constraints, excluded volume, and attractive van der Waals interactions to 1) rank the binding affinity of mutants of tetratricopeptide repeat proteins with their cognate peptides, 2) rank the energetics of binding of small designed proteins to the hydrophobic stem region of the influenza hemagglutinin protein, and 3) predict the stability of T4 lysozyme and staphylococcal nuclease mutants. This work will not only lead to a fundamental understanding of protein-protein interactions, but also to the development of efficient computational methods to rationally design protein interfaces with tunable specificity and affinity, and numerous applications in biomedicine. NSF DMR-1006537, PHY-1019147, Raymond and Beverly Sackler Institute for Biological, Physical and Engineering Sciences, and Howard Hughes Medical Institute.

  1. Design of Maternity Pillow by Using Kansei and Taguchi Methods

    NASA Astrophysics Data System (ADS)

    Ilma Rahmillah, Fety; Nanda kartika, Rachmah

    2017-06-01

    One of the customers’ considerations for purchasing a product is it can satisfy their feeling and emotion. It because of such product can enhance sleep quality of pregnant women. However, most of the existing product such as maternity pillows are still designed based on companies’ perspective. This study aims to capture the desire of pregnant women toward maternity pillow desired product by using kansei words and analyze the optimal design with Taguchi method. Eight collected kansei words were durable, aesthetic, comfort, portable, simple, multifunction, attractive motive, and easy to maintain. While L16 orthogonal array is used because there are three variables with two levels and four variables with four levels. It can be concluded that the best maternity pillow that can satisfy the customers can be designed by combining D1-E2-F2-G2-C1-B2-A2 means the model is U shape, flowery motive, medium color, Bag model B, cotton pillow cover, filled with silicon, and use double zipper. However, it is also possible to create combination of D1-E2-F2-G2-C1-B1-A1 by using consideration of cost which means that the zipper is switched to single as well as filled with dacron. In addition, the total percentage of contribution by using ANOVA reaches 95%.

  2. 77 FR 60985 - Ambient Air Monitoring Reference and Equivalent Methods: Designation of Three New Equivalent Methods

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-05

    ... for Air Pollution Measurement Systems, Volume I,'' EPA/600/R-94/038a and ``Quality Assurance Handbook for Air Pollution Measurement Systems, Volume II, Ambient Air Quality Monitoring Program'' EPA-454/B... AGENCY Ambient Air Monitoring Reference and Equivalent Methods: Designation of Three New...

  3. A New Aerodynamic Data Dispersion Method for Launch Vehicle Design

    NASA Technical Reports Server (NTRS)

    Pinier, Jeremy T.

    2011-01-01

    A novel method for implementing aerodynamic data dispersion analysis is herein introduced. A general mathematical approach combined with physical modeling tailored to the aerodynamic quantity of interest enables the generation of more realistically relevant dispersed data and, in turn, more reasonable flight simulation results. The method simultaneously allows for the aerodynamic quantities and their derivatives to be dispersed given a set of non-arbitrary constraints, which stresses the controls model in more ways than with the traditional bias up or down of the nominal data within the uncertainty bounds. The adoption and implementation of this new method within the NASA Ares I Crew Launch Vehicle Project has resulted in significant increases in predicted roll control authority, and lowered the induced risks for flight test operations. One direct impact on launch vehicles is a reduced size for auxiliary control systems, and the possibility of an increased payload. This technique has the potential of being applied to problems in multiple areas where nominal data together with uncertainties are used to produce simulations using Monte Carlo type random sampling methods. It is recommended that a tailored physics-based dispersion model be delivered with any aerodynamic product that includes nominal data and uncertainties, in order to make flight simulations more realistic and allow for leaner spacecraft designs.

  4. Development of Analysis Methods for Designing with Composites

    NASA Technical Reports Server (NTRS)

    Madenci, E.

    1999-01-01

    The project involved the development of new analysis methods to achieve efficient design of composite structures. We developed a complex variational formulation to analyze the in-plane and bending coupling response of an unsymmetrically laminated plate with an elliptical cutout subjected to arbitrary edge loading as shown in Figure 1. This formulation utilizes four independent complex potentials that satisfy the coupled in-plane and bending equilibrium equations, thus eliminating the area integrals from the strain energy expression. The solution to a finite geometry laminate under arbitrary loading is obtained by minimizing the total potential energy function and solving for the unknown coefficients of the complex potentials. The validity of this approach is demonstrated by comparison with finite element analysis predictions for a laminate with an inclined elliptical cutout under bi-axial loading.The geometry and loading of this laminate with a lay-up of [-45/45] are shown in Figure 2. The deformed configuration shown in Figure 3 reflects the presence of bending-stretching coupling. The validity of the present method is established by comparing the out-of-plane deflections along the boundary of the elliptical cutout from the present approach with those of the finite element method. The comparison shown in Figure 4 indicates remarkable agreement. The details of this method are described in a manuscript by Madenci et al. (1998).

  5. Ceramic bracket design: an analysis using the finite element method.

    PubMed

    Ghosh, J; Nanda, R S; Duncanson, M G; Currier, G F

    1995-12-01

    This investigation was designed to generate finite element models for selected ceramic brackets and graphically display the stress distribution in the brackets when subjected to arch wire torsion and tipping forces. Six commercially available ceramic brackets, one monocrystalline and five polycrystalline alumina, of twin bracket design for the permanent maxillary left central incisor were studied. Three-dimensional computer models of the brackets were constructed and loading forces, similar to those applied by a full-size (0.0215 x 0.028 inch) stainless steel arch wire in torsion and tipping necessary to fracture ceramic brackets, were applied to the models. Stress levels were recorded at relevant points common among the various brackets. High stress levels were observed at areas of abrupt change in geometry and shape. The design of the wire slot and wings for the Contour bracket (Class One Orthodontic Products, Lubbock, Texas) and of the outer edges of the wire slot for the Allure bracket (GAC, Central Islip, N.Y.) were found to be good in terms of even stress distribution. The brackets with an isthmus connecting the wings seemed to resist stresses better than the one bracket that did not have this feature. The design of the isthmus for the Transcend (Unitek/3M, Monrovia, Calif.) and Lumina (Ormco, Glendora, Calif.) brackets were found to be acceptable as well. The Starfire bracket ("A" Company, San Diego, Calif.) showed high stresses and irregular stress distribution, because it had sharp angles, no rounded corners, and no isthmus. The finite element method proved to be a useful tool in the stress analysis of ceramic orthodontic brackets subjected to various forces.(ABSTRACT TRUNCATED AT 250 WORDS)

  6. An analytical filter design method for guided wave phased arrays

    NASA Astrophysics Data System (ADS)

    Kwon, Hyu-Sang; Kim, Jin-Yeon

    2016-12-01

    This paper presents an analytical method for designing a spatial filter that processes the data from an array of two-dimensional guided wave transducers. An inverse problem is defined where the spatial filter coefficients are determined in such a way that a prescribed beam shape, i.e., a desired array output is best approximated in the least-squares sense. Taking advantage of the 2π-periodicity of the generated wave field, Fourier-series representation is used to derive closed-form expressions for the constituting matrix elements. Special cases in which the desired array output is an ideal delta function and a gate function are considered in a more explicit way. Numerical simulations are performed to examine the performance of the filters designed by the proposed method. It is shown that the proposed filters can significantly improve the beam quality in general. Most notable is that the proposed method does not compromise between the main lobe width and the sidelobe levels; i.e. a narrow main lobe and low sidelobes are simultaneously achieved. It is also shown that the proposed filter can compensate the effects of nonuniform directivity and sensitivity of array elements by explicitly taking these into account in the formulation. From an example of detecting two separate targets, how much the angular resolution can be improved as compared to the conventional delay-and-sum filter is quantitatively illustrated. Lamb wave based imaging of localized defects in an elastic plate using a circular array is also presented as an example of practical applications.

  7. Formal methods in the design of Ada 1995

    NASA Technical Reports Server (NTRS)

    Guaspari, David

    1995-01-01

    Formal, mathematical methods are most useful when applied early in the design and implementation of a software system--that, at least, is the familiar refrain. I will report on a modest effort to apply formal methods at the earliest possible stage, namely, in the design of the Ada 95 programming language itself. This talk is an 'experience report' that provides brief case studies illustrating the kinds of problems we worked on, how we approached them, and the extent (if any) to which the results proved useful. It also derives some lessons and suggestions for those undertaking future projects of this kind. Ada 95 is the first revision of the standard for the Ada programming language. The revision began in 1988, when the Ada Joint Programming Office first asked the Ada Board to recommend a plan for revising the Ada standard. The first step in the revision was to solicit criticisms of Ada 83. A set of requirements for the new language standard, based on those criticisms, was published in 1990. A small design team, the Mapping Revision Team (MRT), became exclusively responsible for revising the language standard to satisfy those requirements. The MRT, from Intermetrics, is led by S. Tucker Taft. The work of the MRT was regularly subject to independent review and criticism by a committee of distinguished Reviewers and by several advisory teams--for example, the two User/Implementor teams, each consisting of an industrial user (attempting to make significant use of the new language on a realistic application) and a compiler vendor (undertaking, experimentally, to modify its current implementation in order to provide the necessary new features). One novel decision established the Language Precision Team (LPT), which investigated language proposals from a mathematical point of view. The LPT applied formal mathematical analysis to help improve the design of Ada 95 (e.g., by clarifying the language proposals) and to help promote its acceptance (e.g., by identifying a

  8. Learning physics: A comparative analysis between instructional design methods

    NASA Astrophysics Data System (ADS)

    Mathew, Easow

    The purpose of this research was to determine if there were differences in academic performance between students who participated in traditional versus collaborative problem-based learning (PBL) instructional design approaches to physics curricula. This study utilized a quantitative quasi-experimental design methodology to determine the significance of differences in pre- and posttest introductory physics exam performance between students who participated in traditional (i.e., control group) versus collaborative problem solving (PBL) instructional design (i.e., experimental group) approaches to physics curricula over a college semester in 2008. There were 42 student participants (N = 42) enrolled in an introductory physics course at the research site in the Spring 2008 semester who agreed to participate in this study after reading and signing informed consent documents. A total of 22 participants were assigned to the experimental group (n = 22) who participated in a PBL based teaching methodology along with traditional lecture methods. The other 20 students were assigned to the control group (n = 20) who participated in the traditional lecture teaching methodology. Both the courses were taught by experienced professors who have qualifications at the doctoral level. The results indicated statistically significant differences (p < .01) in academic performance between students who participated in traditional (i.e., lower physics posttest scores and lower differences between pre- and posttest scores) versus collaborative (i.e., higher physics posttest scores, and higher differences between pre- and posttest scores) instructional design approaches to physics curricula. Despite some slight differences in control group and experimental group demographic characteristics (gender, ethnicity, and age) there were statistically significant (p = .04) differences between female average academic improvement which was much higher than male average academic improvement (˜63%) in

  9. PARTIAL RESTRAINING FORCE INTRODUCTION METHOD FOR DESIGNING CONSTRUCTION COUNTERMESURE ON ΔB METHOD

    NASA Astrophysics Data System (ADS)

    Nishiyama, Taku; Imanishi, Hajime; Chiba, Noriyuki; Ito, Takao

    Landslide or slope failure is a three-dimensional movement phenomenon, thus a three-dimensional treatment makes it easier to understand stability. The ΔB method (simplified three-dimensional slope stability analysis method) is based on the limit equilibrium method and equals to an approximate three-dimensional slope stability analysis that extends two-dimensional cross-section stability analysis results to assess stability. This analysis can be conducted using conventional spreadsheets or two-dimensional slope stability computational software. This paper describes the concept of the partial restraining force in-troduction method for designing construction countermeasures using the distribution of the restraining force found along survey lines, which is based on the distribution of survey line safety factors derived from the above-stated analysis. This paper also presents the transverse distributive method of restraining force used for planning ground stabilizing on the basis of the example analysis.

  10. Basic research on design analysis methods for rotorcraft vibrations

    NASA Astrophysics Data System (ADS)

    Hanagud, S.

    1991-12-01

    The objective of the present work was to develop a method for identifying physically plausible finite element system models of airframe structures from test data. The assumed models were based on linear elastic behavior with general (nonproportional) damping. Physical plausibility of the identified system matrices was insured by restricting the identification process to designated physical parameters only and not simply to the elements of the system matrices themselves. For example, in a large finite element model the identified parameters might be restricted to the moduli for each of the different materials used in the structure. In the case of damping, a restricted set of damping values might be assigned to finite elements based on the material type and on the fabrication processes used. In this case, different damping values might be associated with riveted, bolted and bonded elements. The method itself is developed first, and several approaches are outlined for computing the identified parameter values. The method is applied first to a simple structure for which the 'measured' response is actually synthesized from an assumed model. Both stiffness and damping parameter values are accurately identified. The true test, however, is the application to a full-scale airframe structure. In this case, a NASTRAN model and actual measured modal parameters formed the basis for the identification of a restricted set of physically plausible stiffness and damping parameters.

  11. Basic research on design analysis methods for rotorcraft vibrations

    NASA Technical Reports Server (NTRS)

    Hanagud, S.

    1991-01-01

    The objective of the present work was to develop a method for identifying physically plausible finite element system models of airframe structures from test data. The assumed models were based on linear elastic behavior with general (nonproportional) damping. Physical plausibility of the identified system matrices was insured by restricting the identification process to designated physical parameters only and not simply to the elements of the system matrices themselves. For example, in a large finite element model the identified parameters might be restricted to the moduli for each of the different materials used in the structure. In the case of damping, a restricted set of damping values might be assigned to finite elements based on the material type and on the fabrication processes used. In this case, different damping values might be associated with riveted, bolted and bonded elements. The method itself is developed first, and several approaches are outlined for computing the identified parameter values. The method is applied first to a simple structure for which the 'measured' response is actually synthesized from an assumed model. Both stiffness and damping parameter values are accurately identified. The true test, however, is the application to a full-scale airframe structure. In this case, a NASTRAN model and actual measured modal parameters formed the basis for the identification of a restricted set of physically plausible stiffness and damping parameters.

  12. Designing arrays for modern high-resolution methods

    SciTech Connect

    Dowla, F.U.

    1987-10-01

    A bearing estimation study of seismic wavefields propagating from a strongly heterogeneous media shows that with the high-resolution MUSIC algorithm the bias of the direction estimate can be reduced by adopting a smaller aperture sub-array. Further, on this sub-array, the bias of the MUSIC algorithm is less than those of the MLM and Bartlett methods. On the full array, the performance for the three different methods are comparable. Improvement in bearing estimation in MUSIC with a reduced aperture might be attributed to increased signal coherency in the array. For methods with less resolution, the improved signal coherency in the smaller array is possible being offset by severe loss of resolution and the presence of weak secondary sources. Building upon the characteristics of real seismic wavefields, a design language has been developed to generate, modify, and test other arrays. Eigenstructures of wavefields and arrays have been studied empirically by simulation of a variety of realistic signals. 6 refs., 5 figs.

  13. Information processing systems, reasoning modules, and reasoning system design methods

    SciTech Connect

    Hohimer, Ryan E.; Greitzer, Frank L.; Hampton, Shawn D.

    2016-08-23

    Information processing systems, reasoning modules, and reasoning system design methods are described. According to one aspect, an information processing system includes working memory comprising a semantic graph which comprises a plurality of abstractions, wherein the abstractions individually include an individual which is defined according to an ontology and a reasoning system comprising a plurality of reasoning modules which are configured to process different abstractions of the semantic graph, wherein a first of the reasoning modules is configured to process a plurality of abstractions which include individuals of a first classification type of the ontology and a second of the reasoning modules is configured to process a plurality of abstractions which include individuals of a second classification type of the ontology, wherein the first and second classification types are different.

  14. Information processing systems, reasoning modules, and reasoning system design methods

    SciTech Connect

    Hohimer, Ryan E.; Greitzer, Frank L.; Hampton, Shawn D.

    2015-08-18

    Information processing systems, reasoning modules, and reasoning system design methods are described. According to one aspect, an information processing system includes working memory comprising a semantic graph which comprises a plurality of abstractions, wherein the abstractions individually include an individual which is defined according to an ontology and a reasoning system comprising a plurality of reasoning modules which are configured to process different abstractions of the semantic graph, wherein a first of the reasoning modules is configured to process a plurality of abstractions which include individuals of a first classification type of the ontology and a second of the reasoning modules is configured to process a plurality of abstractions which include individuals of a second classification type of the ontology, wherein the first and second classification types are different.

  15. Method for computationally efficient design of dielectric laser accelerator structures.

    PubMed

    Hughes, Tyler; Veronis, Georgios; Wootton, Kent P; Joel England, R; Fan, Shanhui

    2017-06-26

    Dielectric microstructures have generated much interest in recent years as a means of accelerating charged particles when powered by solid state lasers. The acceleration gradient (or particle energy gain per unit length) is an important figure of merit. To design structures with high acceleration gradients, we explore the adjoint variable method, a highly efficient technique used to compute the sensitivity of an objective with respect to a large number of parameters. With this formalism, the sensitivity of the acceleration gradient of a dielectric structure with respect to its entire spatial permittivity distribution is calculated by the use of only two full-field electromagnetic simulations, the original and 'adjoint'. The adjoint simulation corresponds physically to the reciprocal situation of a point charge moving through the accelerator gap and radiating. Using this formalism, we perform numerical optimizations aimed at maximizing acceleration gradients, which generate fabricable structures of greatly improved performance in comparison to previously examined geometries.

  16. Information processing systems, reasoning modules, and reasoning system design methods

    SciTech Connect

    Hohimer, Ryan E; Greitzer, Frank L; Hampton, Shawn D

    2014-03-04

    Information processing systems, reasoning modules, and reasoning system design methods are described. According to one aspect, an information processing system includes working memory comprising a semantic graph which comprises a plurality of abstractions, wherein the abstractions individually include an individual which is defined according to an ontology and a reasoning system comprising a plurality of reasoning modules which are configured to process different abstractions of the semantic graph, wherein a first of the reasoning modules is configured to process a plurality of abstractions which include individuals of a first classification type of the ontology and a second of the reasoning modules is configured to process a plurality of abstractions which include individuals of a second classification type of the ontology, wherein the first and second classification types are different.

  17. Development of impact design methods for ceramic gas turbine components

    NASA Technical Reports Server (NTRS)

    Song, J.; Cuccio, J.; Kington, H.

    1990-01-01

    Impact damage prediction methods are being developed to aid in the design of ceramic gas turbine engine components with improved impact resistance. Two impact damage modes were characterized: local, near the impact site, and structural, usually fast fracture away from the impact site. Local damage to Si3N4 impacted by Si3N4 spherical projectiles consists of ring and/or radial cracks around the impact point. In a mechanistic model being developed, impact damage is characterized as microcrack nucleation and propagation. The extent of damage is measured as volume fraction of microcracks. Model capability is demonstrated by simulating late impact tests. Structural failure is caused by tensile stress during impact exceeding material strength. The EPIC3 code was successfully used to predict blade structural failures in different size particle impacts on radial and axial blades.

  18. POWER ANALYSIS FOR COMPLEX MEDIATIONAL DESIGNS USING MONTE CARLO METHODS

    PubMed Central

    Thoemmes, Felix; MacKinnon, David P.; Reiser, Mark R.

    2013-01-01

    Applied researchers often include mediation effects in applications of advanced methods such as latent variable models and linear growth curve models. Guidance on how to estimate statistical power to detect mediation for these models has not yet been addressed in the literature. We describe a general framework for power analyses for complex mediational models. The approach is based on the well known technique of generating a large number of samples in a Monte Carlo study, and estimating power as the percentage of cases in which an estimate of interest is significantly different from zero. Examples of power calculation for commonly used mediational models are provided. Power analyses for the single mediator, multiple mediators, three-path mediation, mediation with latent variables, moderated mediation, and mediation in longitudinal designs are described. Annotated sample syntax for Mplus is appended and tabled values of required sample sizes are shown for some models. PMID:23935262

  19. Unique Method for Generating Design Earthquake Time Histories

    SciTech Connect

    R. E. Spears

    2008-07-01

    A method has been developed which takes a seed earthquake time history and modifies it to produce given design response spectra. It is a multi-step process with an initial scaling step and then multiple refinement steps. It is unique in the fact that both the acceleration and displacement response spectra are considered when performing the fit (which primarily improves the low frequency acceleration response spectrum accuracy). Additionally, no matrix inversion is needed. The features include encouraging the code acceleration, velocity, and displacement ratios and attempting to fit the pseudo velocity response spectrum. Also, “smoothing” is done to transition the modified time history to the seed time history at its start and end. This is done in the time history regions below a cumulative energy of 5% and above a cumulative energy of 95%. Finally, the modified acceleration, velocity, and displacement time histories are adjusted to start and end with an amplitude of zero (using Fourier transform techniques for integration).

  20. A Design Method for FES Bone Health Therapy in SCI

    PubMed Central

    Andrews, Brian; Shippen, James; Armengol, Monica; Gibbons, Robin; Holderbaum, William; Harwin, William

    2016-01-01

    FES assisted activities such as standing, walking, cycling and rowing induce forces within the leg bones and have been proposed to reduce osteoporosis in spinal cord injury (SCI). However, details of the applied mechanical stimulus for osteogenesis is often not reported. Typically, comparisons of bone density results are made after costly and time consuming clinical trials. These studies have produced inconsistent results and are subject to sample size variations. Here we propose a design process that may be used to predict the clinical outcome based on biomechanical simulation and mechano-biology. This method may allow candidate therapies to be optimized and quantitatively compared. To illustrate the approach we have used data obtained from a rower with complete paraplegia using the RowStim (III) system. PMID:28078075

  1. Design of composite laminates by a Monte Carlo method

    NASA Astrophysics Data System (ADS)

    Fang, Chin; Springer, George S.

    1993-01-01

    A Monte Carlo procedure was developed for optimizing symmetric fiber reinforced composite laminates such that the weight is minimum and the Tsai-Wu strength failure criterion is satisfied in each ply. The laminate may consist of several materials including an idealized core, and may be subjected to several sets of combined in-plane and bending loads. The procedure yields the number of plies, the fiber orientation, and the material of each ply and the material and thickness of the core. A user friendly computer code was written for performing the numerical calculations. Laminates optimized by the code were compared to laminates resulting from existing optimization methods. These comparisons showed that the present Monte Carlo procedure is a useful and efficient tool for the design of composite laminates.

  2. Design method of water jet pump towards high cavitation performances

    NASA Astrophysics Data System (ADS)

    Cao, L. L.; Che, B. X.; Hu, L. J.; Wu, D. Z.

    2016-05-01

    As one of the crucial components for power supply, the propulsion system is of great significance to the advance speed, noise performances, stabilities and other associated critical performances of underwater vehicles. Developing towards much higher advance speed, the underwater vehicles make more critical demands on the performances of the propulsion system. Basically, the increased advance speed requires the significantly raised rotation speed of the propulsion system, which would result in the deteriorated cavitation performances and consequently limit the thrust and efficiency of the whole system. Compared with the traditional propeller, the water jet pump offers more favourite cavitation, propulsion efficiency and other associated performances. The present research focuses on the cavitation performances of the waterjet pump blade profile in expectation of enlarging its advantages in high-speed vehicle propulsion. Based on the specifications of a certain underwater vehicle, the design method of the waterjet blade with high cavitation performances was investigated in terms of numerical simulation.

  3. On the feasibility of a transient dynamic design analysis method

    NASA Astrophysics Data System (ADS)

    Ohara, George J.; Cunniff, Patrick F.

    1992-04-01

    This Annual Report summarizes the progress that was made during the first year of the two-year grant from the Office of Naval Research. The dynamic behavior of structures subjected to mechanical shock loading provides a continuing problem for design engineers concerned with shipboard foundations supporting critical equipment. There are two particular problems associated with shock response that are currently under investigation. The first topic explores the possibilities of developing a transient design analysis method that does not degrade the current level of the Navy's shock-proofness requirements for heavy shipboard equipment. The second topic examines the prospects of developing scaling rules for the shock response of simple internal equipment of submarines subjected to various attack situations. This effort has been divided into two tasks: chemical explosive scaling for a given hull; and scaling of equipment response across different hull sizes. The computer is used as a surrogate shock machine for these studies. Hence, the results of the research can provide trends, ideas, suggestions, and scaling rules to the Navy. In using these results, the shock-hardening program should use measured data rather than calculated data.

  4. The Aging, Demographics, and Memory Study: study design and methods.

    PubMed

    Langa, Kenneth M; Plassman, Brenda L; Wallace, Robert B; Herzog, A Regula; Heeringa, Steven G; Ofstedal, Mary Beth; Burke, James R; Fisher, Gwenith G; Fultz, Nancy H; Hurd, Michael D; Potter, Guy G; Rodgers, Willard L; Steffens, David C; Weir, David R; Willis, Robert J

    2005-01-01

    We describe the design and methods of the Aging, Demographics, and Memory Study (ADAMS), a new national study that will provide data on the antecedents, prevalence, outcomes, and costs of dementia and "cognitive impairment, not demented" (CIND) using a unique study design based on the nationally representative Health and Retirement Study (HRS). We also illustrate potential uses of the ADAMS data and provide information to interested researchers on obtaining ADAMS and HRS data. The ADAMS is the first population-based study of dementia in the United States to include subjects from all regions of the country, while at the same time using a single standardized diagnostic protocol in a community-based sample. A sample of 856 individuals age 70 or older who were participants in the ongoing HRS received an extensive in-home clinical and neuropsychological assessment to determine a diagnosis of normal, CIND, or dementia. Within the CIND and dementia categories, subcategories (e.g. Alzheimer's disease, vascular dementia) were assigned to denote the etiology of cognitive impairment. Linking the ADAMS dementia clinical assessment data to the wealth of available longitudinal HRS data on health, health care utilization, informal care, and economic resources and behavior, will provide a unique opportunity to study the onset of CIND and dementia in a nationally representative population-based sample, as well as the risk factors, prevalence, outcomes, and costs of CIND and dementia. Copyright (c) 2005 S. Karger AG, Basel.

  5. Inflammation and Exercise (INFLAME): study rationale, design, and methods

    PubMed Central

    Thompson, Angela; Mikus, Catherine; Rodarte, Ruben Q.; Distefano, Brandy; Priest, Elisa L.; Sinclair, Erin; Earnest, Conrad P.; Blair, Steven N.; Church, Timothy S.

    2008-01-01

    Purpose The INFLAME study is designed to determine the effect of exercise training on elevated high-sensitivity C-Reactive Protein (CRP) concentrations in initially sedentary women and men. Methods INFLAME will recruit 170 healthy, sedentary women and men with elevated CRP (≥2.0 mg/L) to be randomized to either an exercise group or non-exercise control group. Exercising individuals will participate in four months of supervised aerobic exercise with a total energy expenditure of 16 kcal • kg−1 • week−1 (KKW). Exercise intensity will be 60–80% of maximal oxygen consumption (VO2 max). Outcome The primary outcome will be change in plasma CRP concentration. Secondary outcomes include visceral adiposity, the cytokines IL-6 and TNF-α, and heart rate variability (HRV) in order to examine potential biological mechanisms whereby exercise might affect CRP concentrations. Summary INFLAME will help us understand the effects of moderate to vigorous exercise on CRP concentrations in sedentary individuals. To our knowledge this will be the largest training study specifically designed to examine the effect of exercise on CRP concentrations. This study has the potential to influence therapeutic applications since CRP measurement is becoming an important clinical measurement in Coronary Heart Disease risk assessment. This study will also contribute to the limited body of literature examining the effect of exercise on the variables of visceral adiposity, cytokines, and heart rate variability. PMID:18024231

  6. TIR collimator designs based on point source and extended source methods

    NASA Astrophysics Data System (ADS)

    Talpur, T.; Herkommer, A.

    2015-09-01

    TIR collimator are essential illumination components demanding high efficiency, accuracy, and uniformity. Various illumination design methods have been developed for different design domains, including tailoring method, design via optimization, mapping and feedback method, and the simultaneous multiple surface (SMS) method. This paper summarizes and compares the performance of these methods along with the advantages and the limitations.

  7. The Method of Complex Characteristics for Design of Transonic Compressors.

    NASA Astrophysics Data System (ADS)

    Bledsoe, Margaret Randolph

    We calculate shockless transonic flows past two -dimensional cascades of airfoils characterized by a prescribed speed distribution. The approach is to find solutions of the partial differential equation (c('2)-u('2)) (PHI)(,xx) - 2uv (PHI)(,xy) + (c('2)-v('2)) (PHI)(,yy) = 0 by the method of complex characteristics. Here (PHI) is the velocity potential, so (DEL)(PHI) = (u,v), and c is the local speed of sound. Our method consists in noting that the coefficients of the equation are analytic, so that we can use analytic continuation, conformal mapping, and a spectral method in the hodograph plane to determine the flow. After complex extension we obtain canonical equations for (PHI) and for the stream function (psi) as well as an explicit map from the hodograph plane to complex characteristic coordinates. In the subsonic case, a new coordinate system is defined in which the flow region corresponds to the interior of an ellipse. We construct special solutions of the flow equations in these coordinates by solving characteristic initial value problems in the ellipse with initial data defined by the complete system of Chebyshev polynomials. The condition (psi) = 0 on the boundary of the ellipse is used to determine the series representation of (PHI) and (psi). The map from the ellipse to the complex flow coordinates is found from data specifying the speed q as a function of the arc length s. The transonic problem for shockless flow becomes well posed after appropriate modifications of this procedure. The nonlinearity of the problem is handled by an iterative method that determines the boundary value problem in the ellipse and the map function in sequence. We have implemented this method as a computer code to design two-dimensional cascades of shockless compressor airfoils with gap-to-chord ratios as low as .5 and supersonic zones on both the upper and lower surfaces. The method may be extended to solve more general boundary value problems for second order partial

  8. A practical method for analyzing factorial designs with heteroscedastic data.

    PubMed

    Vallejo, Guiillermo; Ato, Manuel; Fernández, M Paula; Livacic-Rojas, Pablo E

    2008-06-01

    The Type I error rates and powers of three recent tests for analyzing nonorthogonal factorial designs under departures from the assumptions of homogeneity and normality were evaluated using Monte Carlo simulation. Specifically, this work compared the performance of the modified Brown-Forsythe procedure, the generalization of Box's method proposed by Brunner, Dette, and Munk, and the mixed-model procedure adjusted by the Kenward-Roger solution available in the SAS statistical package. With regard to robustness, the three approaches adequately controlled Type I error when the data were generated from symmetric distributions; however, this study's results indicate that, when the data were extracted from asymmetric distributions, the modified Brown-Forsythe approach controlled the Type I error slightly better than the other procedures. With regard to sensitivity, the higher power rates were obtained when the analyses were done with the MIXED procedure of the SAS program. Furthermore, results also identified that, when the data were generated from symmetric distributions, little power was sacrificed by using the generalization of Box's method in place of the modified Brown-Forsythe procedure.

  9. Rationale, design and methods of the CASHMERE study.

    PubMed

    Simon, Tabassome; Boutouyrie, Pierre; Gompel, Anne; Christin-Maitre, Sophie; Laurent, Stéphane; Thuillez, Christian; Zannad, Faiez; Bernaud, Corine; Jaillon, Patrice

    2004-02-01

    Carotid intima-media thickness (IMT) measurement is a noninvasive method used for quantification of early stage of atherosclerosis. Data suggest that the combination of statin and hormone replacement therapy (HRT) might be useful in reducing the early progression of atherosclerosis in postmenopausal women. The main aim of the study is to compare the effects of 12-month therapy with atorvastatin (80 mg/day), HRT (oral 17beta-estradiol 1 or 2 mg/day, plus cyclic dydrogesterone 10 mg) alone and their combination vs. placebo on the progression of carotid IMT by using a high-definition echotracking device. The secondary objectives are to assess the effects of the treatments vs. placebo on arterial stiffness, lipid profile and C-reactive protein. The CASHMERE trial is an European randomized study with a 2 x 2-factorial design, double blinded for atorvastatin and prospective randomized, open blinded endpoint evaluation (PROBE) method applied to HRT. The investigators can adjust the dose of estradiol at any time during follow-up if necessary. A total of 800 postmenopausal women with mild hypercholesterolemia and with no previous history of cardiovascular disease will be included and followed up by their physicians [general practitioners (GPs) or gynecologists] for 1 year. The CASHMERE trial is the first randomized clinical trial to examine the effects of a statin alone or combined with HRT on the structure and the function of carotid artery as early markers of atherosclerosis in postmenopausal women with mild hypercholesterolemia. The results are expected for 2007.

  10. Why consumers behave as they do with respect to food safety and risk information.

    PubMed

    Verbeke, Wim; Frewer, Lynn J; Scholderer, Joachim; De Brabander, Hubert F

    2007-03-14

    In recent years, it seems that consumers are generally uncertain about the safety and quality of their food and their risk perception differs substantially from that of experts. Hormone and veterinary drug residues in meat persist to occupy a high position in European consumers' food concern rankings. The aim of this contribution is to provide a better understanding to food risk analysts of why consumers behave as they do with respect to food safety and risk information. This paper presents some cases of seemingly irrational and inconsistent consumer behaviour with respect to food safety and risk information and provides explanations for these behaviours based on the nature of the risk and individual psychological processes. Potential solutions for rebuilding consumer confidence in food safety and bridging between lay and expert opinions towards food risks are reviewed. These include traceability and labelling, segmented communication approaches and public involvement in risk management decision-making.

  11. Disclosure and rationality: comparative risk information and decision-making about prevention.

    PubMed

    Schwartz, Peter H

    2009-01-01

    With the growing focus on prevention in medicine, studies of how to describe risk have become increasing important. Recently, some researchers have argued against giving patients "comparative risk information," such as data about whether their baseline risk of developing a particular disease is above or below average. The concern is that giving patients this information will interfere with their consideration of more relevant data, such as the specific chance of getting the disease (the "personal risk"), the risk reduction the treatment provides, and any possible side effects. I explore this view and the theories of rationality that ground it, and I argue instead that comparative risk information can play a positive role in decision-making. The criticism of disclosing this sort of information to patients, I conclude, rests on a mistakenly narrow account of the goals of prevention and the nature of rational choice in medicine.

  12. Integrating Climate and Risk-Informed Science to Support Critical Decisions

    SciTech Connect

    2016-07-27

    The PNNL Environmental Health and Remediation Sector stewards several decision support capabilities to integrate climate- and risk-informed science to support critical decisions. Utilizing our expertise in risk and decision analysis, integrated Earth systems modeling, and remote sensing and geoinformatics, PNNL is influencing the way science informs high level decisions at national, regional and local scales to protect and preserve our most critical assets.

  13. Integrating Climate and Risk-Informed Science to Support Critical Decisions

    ScienceCinema

    None

    2016-08-10

    The PNNL Environmental Health and Remediation Sector stewards several decision support capabilities to integrate climate- and risk-informed science to support critical decisions. Utilizing our expertise in risk and decision analysis, integrated Earth systems modeling, and remote sensing and geoinformatics, PNNL is influencing the way science informs high level decisions at national, regional and local scales to protect and preserve our most critical assets.

  14. Effects of racial and ethnic group and health literacy on responses to genomic risk information in a medically underserved population.

    PubMed

    Kaphingst, Kimberly A; Stafford, Jewel D; McGowan, Lucy D'Agostino; Seo, Joann; Lachance, Christina R; Goodman, Melody S

    2015-02-01

    Few studies have examined how individuals respond to genomic risk information for common, chronic diseases. This randomized study examined differences in responses by type of genomic information (genetic test/family history) and disease condition (diabetes/heart disease), and by race/ethnicity in a medically underserved population. 1,057 English-speaking adults completed a survey containing 1 of 4 vignettes (2-by-2 randomized design). Differences in dependent variables (i.e., interest in receiving genomic assessment, discussing with doctor or family, changing health habits) by experimental condition and race/ethnicity were examined using chi-squared tests and multivariable regression analysis. No significant differences were found in dependent variables by type of genomic information or disease condition. In multivariable models, Hispanics were more interested in receiving a genomic assessment than Whites (OR = 1.93; p < .0001); respondents with marginal (OR = 1.54; p = .005) or limited (OR = 1.85; p = .009) health literacy had greater interest than those with adequate health literacy. Blacks (OR = 1.78; p = .001) and Hispanics (OR = 1.85; p = .001) had greater interest in discussing information with family than Whites. Non-Hispanic Blacks (OR = 1.45; p = .04) had greater interest in discussing genomic information with a doctor than Whites. Blacks (β = -0.41; p < .001) and Hispanics (β = -0.25; p = .033) intended to change fewer health habits than Whites; health literacy was negatively associated with number of health habits participants intended to change. Findings suggest that race/ethnicity may affect responses to genomic risk information. Additional research could examine how cognitive representations of this information differ across racial/ethnic groups. Health literacy is also critical to consider in developing approaches to communicating genomic information.

  15. Defensively biased responding to risk information among alcohol-using college students.

    PubMed

    Leffingwell, Thad R; Neumann, Christopher; Leedy, Melissa J; Babitzke, Alison C

    2007-01-01

    Previous research has found that individuals who engage in risky health behaviors respond to health risk messages in a self-serving manner, limiting the impact of health messages among targeted individuals. The present study sought to investigate whether alcohol-using college students would respond to risk messages about alcohol use with a similar defensive bias. Both alcohol-using (N=244) and non-using (N=91) college students read a summary of alcohol risk information intended for college students. Participants then reported their attitudes about the seriousness of the problem of college drinking, personal risk, and the scientific credibility of the risk information. Results indicated that high-risk participants responded in a self-serving manner, with significantly lower ratings of problem importance among alcohol-using students and non-significant differences among assessments of personal risk between groups. Further, alcohol-using students were more critical of the scientific merit of the risk information and more skeptical about the empirical claims. Defensively biased responding was more pronounced among more frequent and heavy drinking students than among lighter drinking students. The implications of these findings as well as possible ways to reduce defensive bias are discussed.

  16. Risk information provided to prospective oocyte donors in a preliminary phone call.

    PubMed

    Gurmankin, A D

    2001-01-01

    In order to accommodate for the present shortage of oocyte donors, oocyte-donation programs place ads in college newspapers and provide large monetary compensation to encourage participation. Large compensation acts as a strong incentive for young women to undergo the potentially risky procedure of donation. In this enticing situation, it is particularly important for programs to fully inform prospective donors of the risks of the procedure so that they can accurately weigh the costs and benefits of donating. However, because oocyte-donor programs must alleviate the shortage of donors if they wish to maintain a financially viable business, there is reason to fear that they may minimize or misrepresent risks when recruiting egg donors. In this pilot study, the risk information provided by programs (n=19) to prospective oocyte donors in a preliminary phone call inquiry was investigated. The majority of the programs provided incomplete and/or inaccurate risk information. Policy changes are recommended to reduce the potential for undue influence and to standardize and regulate the risk information provided to prospective egg donors.

  17. 78 FR 22349 - Guidance on the Treatment of Uncertainties Associated With PRA in Risk-Informed Decisionmaking

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-15

    ... COMMISSION Guidance on the Treatment of Uncertainties Associated With PRA in Risk-Informed Decisionmaking..., Revision 1, ``Guidance on the Treatment of Uncertainties Associated with PRA in Risk-Informed... INFORMATION: NUREG-1855, Revision 1, Guidance on the Treatment of Uncertainties Associated with PRA in...

  18. Design optimization methods for genomic DNA tiling arrays

    PubMed Central

    Bertone, Paul; Trifonov, Valery; Rozowsky, Joel S.; Schubert, Falk; Emanuelsson, Olof; Karro, John; Kao, Ming-Yang; Snyder, Michael; Gerstein, Mark

    2006-01-01

    A recent development in microarray research entails the unbiased coverage, or tiling, of genomic DNA for the large-scale identification of transcribed sequences and regulatory elements. A central issue in designing tiling arrays is that of arriving at a single-copy tile path, as significant sequence cross-hybridization can result from the presence of non-unique probes on the array. Due to the fragmentation of genomic DNA caused by the widespread distribution of repetitive elements, the problem of obtaining adequate sequence coverage increases with the sizes of subsequence tiles that are to be included in the design. This becomes increasingly problematic when considering complex eukaryotic genomes that contain many thousands of interspersed repeats. The general problem of sequence tiling can be framed as finding an optimal partitioning of non-repetitive subsequences over a prescribed range of tile sizes, on a DNA sequence comprising repetitive and non-repetitive regions. Exact solutions to the tiling problem become computationally infeasible when applied to large genomes, but successive optimizations are developed that allow their practical implementation. These include an efficient method for determining the degree of similarity of many oligonucleotide sequences over large genomes, and two algorithms for finding an optimal tile path composed of longer sequence tiles. The first algorithm, a dynamic programming approach, finds an optimal tiling in linear time and space; the second applies a heuristic search to reduce the space complexity to a constant requirement. A Web resource has also been developed, accessible at http://tiling.gersteinlab.org, to generate optimal tile paths from user-provided DNA sequences. PMID:16365382

  19. A Universal Design Method for Reflecting Physical Characteristics Variability: Case Study of a Bicycle Frame.

    PubMed

    Shimada, Masato; Suzuki, Wataru; Yamada, Shuho; Inoue, Masato

    2016-01-01

    To achieve a Universal Design, designers must consider diverse users' physical and functional requirements for their products. However, satisfying these requirements and obtaining the information which is necessary for designing a universal product is very difficult. Therefore, we propose a new design method based on the concept of set-based design to solve these issues. This paper discusses the suitability of proposed design method by applying bicycle frame design problem.

  20. Methods in Enzymology: “Flexible backbone sampling methods to model and design protein alternative conformations”

    PubMed Central

    Ollikainen, Noah; Smith, Colin A.; Fraser, James S.; Kortemme, Tanja

    2013-01-01

    Sampling alternative conformations is key to understanding how proteins work and engineering them for new functions. However, accurately characterizing and modeling protein conformational ensembles remains experimentally and computationally challenging. These challenges must be met before protein conformational heterogeneity can be exploited in protein engineering and design. Here, as a stepping stone, we describe methods to detect alternative conformations in proteins and strategies to model these near-native conformational changes based on backrub-type Monte Carlo moves in Rosetta. We illustrate how Rosetta simulations that apply backrub moves improve modeling of point mutant side chain conformations, native side chain conformational heterogeneity, functional conformational changes, tolerated sequence space, protein interaction specificity, and amino acid co-variation across protein-protein interfaces. We include relevant Rosetta command lines and RosettaScripts to encourage the application of these types of simulations to other systems. Our work highlights that critical scoring and sampling improvements will be necessary to approximate conformational landscapes. Challenges for the future development of these methods include modeling conformational changes that propagate away from designed mutation sites and modulating backbone flexibility to predictively design functionally important conformational heterogeneity. PMID:23422426

  1. Visual Narrative Research Methods as Performance in Industrial Design Education

    ERIC Educational Resources Information Center

    Campbell, Laurel H.; McDonagh, Deana

    2009-01-01

    This article discusses teaching empathic research methodology as performance. The authors describe their collaboration in an activity to help undergraduate industrial design students learn empathy for others when designing products for use by diverse or underrepresented people. The authors propose that an industrial design curriculum would benefit…

  2. Visual Narrative Research Methods as Performance in Industrial Design Education

    ERIC Educational Resources Information Center

    Campbell, Laurel H.; McDonagh, Deana

    2009-01-01

    This article discusses teaching empathic research methodology as performance. The authors describe their collaboration in an activity to help undergraduate industrial design students learn empathy for others when designing products for use by diverse or underrepresented people. The authors propose that an industrial design curriculum would benefit…

  3. Pseudo-Sibship Methods in the Case-Parents Design

    PubMed Central

    Yu, Zhaoxia; Deng, Li

    2013-01-01

    Recent evidence suggests that complex traits are likely determined by multiple loci, with each of which contributes a weak to moderate individual effect. Although extensive literature exists on multi-locus analysis of unrelated subjects, there are relatively fewer strategies for jointly analyzing multiple loci using family data. Here we address this issue by evaluating two pseudo-sibship methods: the 1:1 matching, which matches each affected offspring to the pseudo sibling formed by the alleles not transmitted to the affected offspring; the exhaustive matching, which matches each affected offspring to the pseudo siblings formed by all the other possible combinations of parental alleles. We prove that the two matching strategies use exactly and approximately the same amount of information from data under additive and multiplicative genetic models, respectively. Using numerical calculations under a variety of models and testing assumptions, we show that compared to the exhaustive matching, the 1:1 matching has comparable asymptotic power in detecting multiplicative / additive effects in single-locus analysis and main effects in multi-locus analysis, and it allows association testing of multiple linked loci. These results pave the way for many existing multi-locus analysis methods developed for the case-control (or matched case-control) design to be applied to case-parents data with minor modifications. As an example, with the 1:1 matching, we applied an L1 regularized regression to a Crohn’s disease dataset. Using the multiple loci selected by our approach, we obtained an order-of-magnitude decrease in p-value and an 18.9% increase in prediction accuracy when comparing to using the most significant individual locus. PMID:21953439

  4. The Influence of Values and Rich Conditions on Designers' Judgments about Useful Instructional Methods

    ERIC Educational Resources Information Center

    Honebein, Peter C.

    2017-01-01

    An instructional designer's values about instructional methods can be a curse or a cure. On one hand, a designer's love affair for a method may cause them to use that method in situations that are not appropriate. On the other hand, that same love affair may inspire a designer to fight for a method when those in power are willing to settle for a…

  5. A New Approach to Comparing Several Equating Methods in the Context of the NEAT Design

    ERIC Educational Resources Information Center

    Sinharay, Sandip; Holland, Paul W.

    2010-01-01

    The nonequivalent groups with anchor test (NEAT) design involves missing data that are missing by design. Three equating methods that can be used with a NEAT design are the frequency estimation equipercentile equating method, the chain equipercentile equating method, and the item-response-theory observed-score-equating method. We suggest an…

  6. Organization method for urban planning design data based on GIS

    NASA Astrophysics Data System (ADS)

    Gao, Huijun; Guo, Dazhi; Zhang, Hao; Tian, Ran

    2006-10-01

    GIS and CAD are two different areas of computer technology and its applications, each is widely used in city planning, design and administration. Taking the data management of city planning in Ningbo, Zhejiang province as an example, and has loaded the basic data into database within an urban planning management information system, this paper puts forward a GIS-based organization solution and format standard of planning & design data, which follows designer's usual practice and requirements for design data prescribed by urban planning administration. It works perfectly in Ningbo Urban Planning and Design management system.

  7. Method for computationally efficient design of dielectric laser accelerator structures

    DOE PAGES

    Hughes, Tyler; Veronis, Georgios; Wootton, Kent P.; ...

    2017-06-22

    Here, dielectric microstructures have generated much interest in recent years as a means of accelerating charged particles when powered by solid state lasers. The acceleration gradient (or particle energy gain per unit length) is an important figure of merit. To design structures with high acceleration gradients, we explore the adjoint variable method, a highly efficient technique used to compute the sensitivity of an objective with respect to a large number of parameters. With this formalism, the sensitivity of the acceleration gradient of a dielectric structure with respect to its entire spatial permittivity distribution is calculated by the use of onlymore » two full-field electromagnetic simulations, the original and ‘adjoint’. The adjoint simulation corresponds physically to the reciprocal situation of a point charge moving through the accelerator gap and radiating. Using this formalism, we perform numerical optimizations aimed at maximizing acceleration gradients, which generate fabricable structures of greatly improved performance in comparison to previously examined geometries.« less

  8. The design method of a dam on gravel stream

    SciTech Connect

    Ni, W.B.; Wu, S.J.; Huang, C.Y.

    1995-12-31

    Due to the intense requirements of electricity and water supply in the past decades, large number of dams, reservoirs and mobile barrages have been completed in Taiwan. These hydraulic structures almost occupied all the sound rock foundations with little overburdens. This indicates that the future ones have to face the situation of high overburdens. Special considerations should be taken to overcome the difficulties of water tight requirement and stability of structures. A case study is presented in this paper. It is a dam built for the purpose of hydropower generation and water supply, and is constructed on a gravel stream with 40 m of overburdens. Design method of this dam is discussed in this paper. Curtain grouting is performed in this dam to reduce the high permeability of gravel to an acceptable level. Caissons are chosen to be the structural foundations in this case study to support heavy loads of the dam and to reduce the difficulty of curtain grouting. Another problem for a dam built on gravel stream is the damage of abrasion and erosion to the stilling basin slabs, the sluice way aprons and the spillway aprons. Discussions on the abrasion-erosion resistant materials are also given in this paper.

  9. An entropy method for floodplain monitoring network design

    NASA Astrophysics Data System (ADS)

    Ridolfi, E.; Yan, K.; Alfonso, L.; Di Baldassarre, G.; Napolitano, F.; Russo, F.; Bates, Paul D.

    2012-09-01

    In recent years an increasing number of flood-related fatalities has highlighted the necessity of improving flood risk management to reduce human and economic losses. In this framework, monitoring of flood-prone areas is a key factor for building a resilient environment. In this paper a method for designing a floodplain monitoring network is presented. A redundant network of cheap wireless sensors (GridStix) measuring water depth is considered over a reach of the River Dee (UK), with sensors placed both in the channel and in the floodplain. Through a Three Objective Optimization Problem (TOOP) the best layouts of sensors are evaluated, minimizing their redundancy, maximizing their joint information content and maximizing the accuracy of the observations. A simple raster-based inundation model (LISFLOOD-FP) is used to generate a synthetic GridStix data set of water stages. The Digital Elevation Model (DEM) that is used for hydraulic model building is the globally and freely available SRTM DEM.

  10. Design and methods of the national Vietnam veterans longitudinal study.

    PubMed

    Schlenger, William E; Corry, Nida H; Kulka, Richard A; Williams, Christianna S; Henn-Haase, Clare; Marmar, Charles R

    2015-09-01

    The National Vietnam Veterans Longitudinal Study (NVVLS) is the second assessment of a representative cohort of US veterans who served during the Vietnam War era, either in Vietnam or elsewhere. The cohort was initially surveyed in the National Vietnam Veterans Readjustment Study (NVVRS) from 1984 to 1988 to assess the prevalence, incidence, and effects of post-traumatic stress disorder (PTSD) and other post-war problems. The NVVLS sought to re-interview the cohort to assess the long-term course of PTSD. NVVLS data collection began July 3, 2012 and ended May 17, 2013, comprising three components: a mailed health questionnaire, a telephone health survey interview, and, for a probability sample of theater Veterans, a clinical diagnostic telephone interview administered by licensed psychologists. Excluding decedents, 78.8% completed the questionnaire and/or telephone survey, and 55.0% of selected living veterans participated in the clinical interview. This report provides a description of the NVVLS design and methods. Together, the NVVRS and NVVLS constitute a nationally representative longitudinal study of Vietnam veterans, and extend the NVVRS as a critical resource for scientific and policy analyses for Vietnam veterans, with policy relevance for Iraq and Afghanistan veterans.

  11. A decision-based perspective for the design of methods for systems design

    NASA Technical Reports Server (NTRS)

    Mistree, Farrokh; Muster, Douglas; Shupe, Jon A.; Allen, Janet K.

    1989-01-01

    Organization of material, a definition of decision based design, a hierarchy of decision based design, the decision support problem technique, a conceptual model design that can be manufactured and maintained, meta-design, computer-based design, action learning, and the characteristics of decisions are among the topics covered.

  12. Active cooling design for scramjet engines using optimization methods

    NASA Technical Reports Server (NTRS)

    Scotti, Stephen J.; Martin, Carl J.; Lucas, Stephen H.

    1988-01-01

    A methodology for using optimization in designing metallic cooling jackets for scramjet engines is presented. The optimal design minimizes the required coolant flow rate subject to temperature, mechanical-stress, and thermal-fatigue-life constraints on the cooling-jacket panels, and Mach-number and pressure constraints on the coolant exiting the panel. The analytical basis for the methodology is presented, and results for the optimal design of panels are shown to demonstrate its utility.

  13. Active cooling design for scramjet engines using optimization methods

    NASA Technical Reports Server (NTRS)

    Scotti, Stephen J.; Martin, Carl J.; Lucas, Stephen H.

    1988-01-01

    A methodology for using optimization in designing metallic cooling jackets for scramjet engines is presented. The optimal design minimizes the required coolant flow rate subject to temperature, mechanical-stress, and thermal-fatigue-life constraints on the cooling-jacket panels, and Mach-number and pressure contraints on the coolant exiting the panel. The analytical basis for the methodology is presented, and results for the optimal design of panels are shown to demonstrate its utility.

  14. Active cooling design for scramjet engines using optimization methods

    NASA Technical Reports Server (NTRS)

    Scotti, Stephen J.; Martin, Carl J.; Lucas, Stephen H.

    1988-01-01

    A methodology for using optimization in designing metallic cooling jackets for scramjet engines is presented. The optimal design minimizes the required coolant flow rate subject to temperature, mechanical-stress, and thermal-fatigue-life constraints on the cooling-jacket panels, and Mach-number and pressure constraints on the coolant exiting the panel. The analytical basis for the methodology is presented, and results for the optimal design of panels are shown to demonstrate its utility.

  15. Genetic algorithm-based design method for multilevel anisotropic diffraction gratings

    NASA Astrophysics Data System (ADS)

    Okamoto, Hiroyuki; Noda, Kohei; Sakamoto, Moritsugu; Sasaki, Tomoyuki; Wada, Yasuhiro; Kawatsuki, Nobuhiro; Ono, Hiroshi

    2017-08-01

    We developed a method for the design of multilevel anisotropic diffraction gratings based on a genetic algorithm. The method is used to design the multilevel anisotropic diffraction gratings based on input data that represent the output from the required grating. The validity of the proposed method was evaluated by designing a multilevel anisotropic diffraction grating using the outputs from an orthogonal circular polarization grating. The design results corresponded to the orthogonal circular polarization grating structures that were used to provide outputs to act as the input data for the process. Comparison with existing design methods shows that the proposed method can reduce the number of human processes that are required to design multilevel anisotropic diffraction gratings. Additionally, the method will be able to design complex structures without any requirement for subsequent examination by a human designer. The method can contribute to the development of optical elements by designing multilevel anisotropic diffraction gratings.

  16. 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.

  17. Investigating a Method of Scaffolding Student-Designed Experiments

    NASA Astrophysics Data System (ADS)

    Morgan, Kelly; Brooks, David W.

    2012-08-01

    The process of designing an experiment is a difficult one. Students often struggle to perform such tasks as the design process places a large cognitive load on students. Scaffolding is the process of providing support for a student to allow them to complete tasks they would otherwise not have been able to complete. This study sought to investigate backwards-design, one form of scaffolding the experimental design process for students. Students were guided through the design process in a backwards manner (designing the results section first and working backwards through typical report components to the materials and safety sections). The use of reflective prompts as possible scaffold for metacognitive processes was also studied. Scaffolding was in the form of a computer application built specifically for this purpose. Four versions of the computer application were randomly assigned to 102 high school chemistry students and students were asked to the design of an experiment, producing a report. The use of backwards-design scaffolding resulted in significantly higher performance on lab reports. The addition of reflective prompts reduced the effect of backwards-design scaffolding in lower-level students.

  18. Multidisciplinary Design Optimization (MDO) Methods: Their Synergy with Computer Technology in Design Process

    NASA Technical Reports Server (NTRS)

    Sobieszczanski-Sobieski, Jaroslaw

    1998-01-01

    The paper identifies speed, agility, human interface, generation of sensitivity information, task decomposition, and data transmission (including storage) as important attributes for a computer environment to have in order to support engineering design effectively. It is argued that when examined in terms of these attributes the presently available environment can be shown to be inadequate a radical improvement is needed, and it may be achieved by combining new methods that have recently emerged from multidisciplinary design optimization (MDO) with massively parallel processing computer technology. The caveat is that, for successful use of that technology in engineering computing, new paradigms for computing will have to be developed - specifically, innovative algorithms that are intrinsically parallel so that their performance scales up linearly with the number of processors. It may be speculated that the idea of simulating a complex behavior by interaction of a large number of very simple models may be an inspiration for the above algorithms, the cellular automata are an example. Because of the long lead time needed to develop and mature new paradigms, development should be now, even though the widespread availability of massively parallel processing is still a few years away.

  19. Multidisciplinary Design Optimisation (MDO) Methods: Their Synergy with Computer Technology in the Design Process

    NASA Technical Reports Server (NTRS)

    Sobieszczanski-Sobieski, Jaroslaw

    1999-01-01

    The paper identifies speed, agility, human interface, generation of sensitivity information, task decomposition, and data transmission (including storage) as important attributes for a computer environment to have in order to support engineering design effectively. It is argued that when examined in terms of these attributes the presently available environment can be shown to be inadequate. A radical improvement is needed, and it may be achieved by combining new methods that have recently emerged from multidisciplinary design optimisation (MDO) with massively parallel processing computer technology. The caveat is that, for successful use of that technology in engineering computing, new paradigms for computing will have to be developed - specifically, innovative algorithms that are intrinsically parallel so that their performance scales up linearly with the number of processors. It may be speculated that the idea of simulating a complex behaviour by interaction of a large number of very simple models may be an inspiration for the above algorithms; the cellular automata are an example. Because of the long lead time needed to develop and mature new paradigms, development should begin now, even though the widespread availability of massively parallel processing is still a few years away.

  20. Multidisciplinary Design Optimisation (MDO) Methods: Their Synergy with Computer Technology in the Design Process

    NASA Technical Reports Server (NTRS)

    Sobieszczanski-Sobieski, Jaroslaw

    1999-01-01

    The paper identifies speed, agility, human interface, generation of sensitivity information, task decomposition, and data transmission (including storage) as important attributes for a computer environment to have in order to support engineering design effectively. It is argued that when examined in terms of these attributes the presently available environment can be shown to be inadequate. A radical improvement is needed, and it may be achieved by combining new methods that have recently emerged from multidisciplinary design optimisation (MDO) with massively parallel processing computer technology. The caveat is that, for successful use of that technology in engineering computing, new paradigms for computing will have to be developed - specifically, innovative algorithms that are intrinsically parallel so that their performance scales up linearly with the number of processors. It may be speculated that the idea of simulating a complex behaviour by interaction of a large number of very simple models may be an inspiration for the above algorithms; the cellular automata are an example. Because of the long lead time needed to develop and mature new paradigms, development should begin now, even though the widespread availability of massively parallel processing is still a few years away.

  1. Multidisciplinary Design Optimization (MDO) Methods: Their Synergy with Computer Technology in Design Process

    NASA Technical Reports Server (NTRS)

    Sobieszczanski-Sobieski, Jaroslaw

    1998-01-01

    The paper identifies speed, agility, human interface, generation of sensitivity information, task decomposition, and data transmission (including storage) as important attributes for a computer environment to have in order to support engineering design effectively. It is argued that when examined in terms of these attributes the presently available environment can be shown to be inadequate a radical improvement is needed, and it may be achieved by combining new methods that have recently emerged from multidisciplinary design optimization (MDO) with massively parallel processing computer technology. The caveat is that, for successful use of that technology in engineering computing, new paradigms for computing will have to be developed - specifically, innovative algorithms that are intrinsically parallel so that their performance scales up linearly with the number of processors. It may be speculated that the idea of simulating a complex behavior by interaction of a large number of very simple models may be an inspiration for the above algorithms, the cellular automata are an example. Because of the long lead time needed to develop and mature new paradigms, development should be now, even though the widespread availability of massively parallel processing is still a few years away.

  2. Applications of numerical optimization methods to helicopter design problems: A survey

    NASA Technical Reports Server (NTRS)

    Miura, H.

    1984-01-01

    A survey of applications of mathematical programming methods is used to improve the design of helicopters and their components. Applications of multivariable search techniques in the finite dimensional space are considered. Five categories of helicopter design problems are considered: (1) conceptual and preliminary design, (2) rotor-system design, (3) airframe structures design, (4) control system design, and (5) flight trajectory planning. Key technical progress in numerical optimization methods relevant to rotorcraft applications are summarized.

  3. Applications of numerical optimization methods to helicopter design problems - A survey

    NASA Technical Reports Server (NTRS)

    Miura, H.

    1984-01-01

    A survey of applications of mathematical programming methods is used to improve the design of helicopters and their components. Applications of multivariable search techniques in the finite dimensional space are considered. Five categories of helicopter design problems are considered: (1) conceptual and preliminary design, (2) rotor-system design, (3) airframe structures design, (4) control system design, and (5) flight trajectory planning. Key technical progress in numerical optimization methods relevant to rotorcraft applications are summarized.

  4. Applications of numerical optimization methods to helicopter design problems - A survey

    NASA Technical Reports Server (NTRS)

    Miura, H.

    1985-01-01

    A survey of applications of mathematical programming methods is used to improve the design of helicopters and their components. Applications of multivariable search techniques in the finite dimensional space are considered. Five categories of helicopter design problems are considered: (1) conceptual and preliminary design, (2) rotor-system design, (3) airframe structures design, (4) control system design, and (5) flight trajectory planning. Key technical progress in numerical optimization methods relevant to rotorcraft applications are summarized.

  5. Inside multi-disciplinary design in medical informatics: experiences from the use of an argumentative design method.

    PubMed

    Sjøberg, C; Timpka, T

    1995-01-01

    This paper reports on a qualitative study using an argumentation-based design method (Argumentative Design) in the development of clinical software systems. The method, which requires visualization of the underlying design goals, the specific needs-for-change, and the probable consequences of the alternative design measures, caused previously implicit argument structures to be exposed and discussed. This uncovering of hidden agendas also revealed previously implicit coalitions and organizational influences on the design process. Implications for software development practices in medical informatics are discussed.

  6. Stillbirth Collaborative Research Network: design, methods and recruitment experience.

    PubMed

    Parker, Corette B; Hogue, Carol J R; Koch, Matthew A; Willinger, Marian; Reddy, Uma M; Thorsten, Vanessa R; Dudley, Donald J; Silver, Robert M; Coustan, Donald; Saade, George R; Conway, Deborah; Varner, Michael W; Stoll, Barbara; Pinar, Halit; Bukowski, Radek; Carpenter, Marshall; Goldenberg, Robert

    2011-09-01

    The Stillbirth Collaborative Research Network (SCRN) has conducted a multisite, population-based, case-control study, with prospective enrollment of stillbirths and livebirths at the time of delivery. This paper describes the general design, methods and recruitment experience. The SCRN attempted to enroll all stillbirths and a representative sample of livebirths occurring to residents of pre-defined geographical catchment areas delivering at 59 hospitals associated with five clinical sites. Livebirths <32 weeks gestation and women of African descent were oversampled. The recruitment hospitals were chosen to ensure access to at least 90% of all stillbirths and livebirths to residents of the catchment areas. Participants underwent a standardised protocol including maternal interview, medical record abstraction, placental pathology, biospecimen testing and, in stillbirths, post-mortem examination. Recruitment began in March 2006 and was completed in September 2008 with 663 women with a stillbirth and 1932 women with a livebirth enrolled, representing 69% and 63%, respectively, of the women identified. Additional surveillance for stillbirths continued until June 2009 and a follow-up of the case-control study participants was completed in December 2009. Among consenting women, there were high consent rates for the various study components. For the women with stillbirths, 95% agreed to a maternal interview, chart abstraction and a placental pathological examination; 91% of the women with a livebirth agreed to all of these components. Additionally, 84% of the women with stillbirths agreed to a fetal post-mortem examination. This comprehensive study is poised to systematically study a wide range of potential causes of, and risk factors for, stillbirths and to better understand the scope and incidence of the problem.

  7. Stillbirth Collaborative Research Network: Design, Methods and Recruitment Experience

    PubMed Central

    Parker, Corette B.; Hogue, Carol J. Rowland; Koch, Matthew A.; Willinger, Marian; Reddy, Uma; Thorsten, Vanessa R.; Dudley, Donald J.; Silver, Robert M.; Coustan, Donald; Saade, George R.; Conway, Deborah; Varner, Michael W.; Stoll, Barbara; Pinar, Halit; Bukowski, Radek; Carpenter, Marshall; Goldenberg, Robert

    2013-01-01

    SUMMARY The Stillbirth Collaborative Research Network (SCRN) has conducted a multisite, population-based, case-control study, with prospective enrollment of stillbirths and live births at the time of delivery. This paper describes the general design, methods, and recruitment experience. The SCRN attempted to enroll all stillbirths and a representative sample of live births occurring to residents of pre-defined geographic catchment areas delivering at 59 hospitals associated with five clinical sites. Live births <32 weeks gestation and women of African descent were oversampled. The recruitment hospitals were chosen to ensure access to at least 90% of all stillbirths and live births to residents of the catchment areas. Participants underwent a standardized protocol including maternal interview, medical record abstraction, placental pathology, biospecimen testing, and, in stillbirths, postmortem examination. Recruitment began in March 2006 and was completed in September 2008 with 663 women with a stillbirth and 1932 women with a live birth enrolled, representing 69% and 63%, respectively, of the women identified. Additional surveillance for stillbirth continued through June 2009 and a follow-up of the case-control study participants was completed in December 2009. Among consenting women, there were high consent rates for the various study components. For the women with stillbirth, 95% agreed to maternal interview, chart abstraction, and placental pathologic examination; 91% of the women with live birth agreed to all of these components. Additionally, 84% of the women with stillbirth agreed to a fetal postmortem examination. This comprehensive study is poised to systematically study a wide range of potential causes of, and risk factors for, stillbirth and to better understand the scope and incidence of the problem. PMID:21819424

  8. Methods for combining payload parameter variations with input environment. [calculating design limit loads compatible with probabilistic structural design criteria

    NASA Technical Reports Server (NTRS)

    Merchant, D. H.

    1976-01-01

    Methods are presented for calculating design limit loads compatible with probabilistic structural design criteria. The approach is based on the concept that the desired limit load, defined as the largest load occurring in a mission, is a random variable having a specific probability distribution which may be determined from extreme-value theory. The design limit load, defined as a particular of this random limit load, is the value conventionally used in structural design. Methods are presented for determining the limit load probability distributions from both time-domain and frequency-domain dynamic load simulations. Numerical demonstrations of the method are also presented.

  9. METHODS FOR INTEGRATING ENVIRONMENTAL CONSIDERATIONS INTO CHEMICAL PROCESS DESIGN DECISIONS

    EPA Science Inventory

    The objective of this cooperative agreement was to postulate a means by which an engineer could routinely include environmental considerations in day-to-day conceptual design problems; a means that could easily integrate with existing design processes, and thus avoid massive retr...

  10. Investigating a Method of Scaffolding Student-Designed Experiments

    ERIC Educational Resources Information Center

    Morgan, Kelly; Brooks, David W.

    2012-01-01

    The process of designing an experiment is a difficult one. Students often struggle to perform such tasks as the design process places a large cognitive load on students. Scaffolding is the process of providing support for a student to allow them to complete tasks they would otherwise not have been able to complete. This study sought to investigate…

  11. Teaching Improvement Model Designed with DEA Method and Management Matrix

    ERIC Educational Resources Information Center

    Montoneri, Bernard

    2014-01-01

    This study uses student evaluation of teachers to design a teaching improvement matrix based on teaching efficiency and performance by combining management matrix and data envelopment analysis. This matrix is designed to formulate suggestions to improve teaching. The research sample consists of 42 classes of freshmen following a course of English…

  12. Preliminary design of pseudo satellites: Basic methods and feasibility criteria

    NASA Astrophysics Data System (ADS)

    Klimenko, N. N.

    2016-12-01

    Analytical models of weight and energy balances, aerodynamic models, and solar irradiance models to perform pseudo-satellite preliminary design are presented. Feasibility criteria are determined in accordance with the aim of preliminary design dependent on mission scenario and type of payload.

  13. METHODS FOR INTEGRATING ENVIRONMENTAL CONSIDERATIONS INTO CHEMICAL PROCESS DESIGN DECISIONS

    EPA Science Inventory

    The objective of this cooperative agreement was to postulate a means by which an engineer could routinely include environmental considerations in day-to-day conceptual design problems; a means that could easily integrate with existing design processes, and thus avoid massive retr...

  14. Developing Baby Bag Design by Using Kansei Engineering Method

    NASA Astrophysics Data System (ADS)

    Janari, D.; Rakhmawati, A.

    2016-01-01

    Consumer's preferences and market demand are essential factors for product's success. Thus, in achieving its success, a product should have design that could fulfill consumer's expectation. Purpose of this research is accomplishing baby bag product as stipulated by Kansei. The results that represent Kanseiwords are; neat, unique, comfortable, safe, modern, gentle, elegant, antique, attractive, simple, spacious, creative, colorful, durable, stylish, smooth and strong. Identification value on significance of correlation for durable attribute is 0,000 < 0,005, which means significant to baby's bag. While the value of coefficient regression is 0,812 < 0,005, which means that durable attribute insignificant to baby's bag.The result of the baby's bag final design selectionbased on the questionnaire 3 is resulting the combination of all design. Space for clothes, diaper's space, shoulder grip, side grip, bottle's heater pocket and bottle's pocket are derived from design 1. Top grip, space for clothes, shoulder grip, and side grip are derived from design 2.Others design that were taken are, spaces for clothes from design 3, diaper's space and clothes’ space from design 4.

  15. Method for systematically designing polarization optics to maximize sensitivity of electrooptic sensors

    NASA Astrophysics Data System (ADS)

    Sasaki, Ai-ichiro; Furuya, Akinori; Hirata, Akihiko; Morimura, Hiroki; Kodate, Junichi

    2017-09-01

    A systematic design method is considered for maximizing the sensitivity of electrooptic sensors used for electric-field detection. The design method can be reduced to a routine procedure that includes matrix manipulation and differentiation. By applying the design method, the maximum sensitivity is realized with fewer optical components than in conventional electrooptic sensing systems. Since the proposed method shows a wide generality, it can be applied to designing sensors including various optical crystals.

  16. Influence of graphic format on comprehension of risk information among American Indians.

    PubMed

    Sprague, Debra; LaVallie, Donna L; Wolf, Fredric M; Jacobsen, Clemma; Sayson, Kirsten; Buchwald, Dedra

    2011-01-01

    Presentation of risk information influences patients' ability to interpret health care options. Little is known about this relationship between risk presentation and interpretation among American Indians. Three hundred American Indian employees on a western American Indian reservation were invited to complete an anonymous written survey. All surveys included a vignette presenting baseline risk information about a hypothetical cancer and possible benefits of 2 prevention plans. Risk interpretation was assessed by correct answers to 3 questions evaluating the risk reduction associated with the plans. Numeric information was the same in all surveys, but framing varied; half expressed prevention benefits in terms of relative risk reduction and half in terms of absolute risk reduction. All surveys used text to describe the benefits of the 2 plans, but half included a graphic image. Surveys were distributed randomly. Responses were analyzed using binary logistic regression with the robust variance estimator to account for clustering of outcomes within participant. Use of a graphic image was associated with higher odds of correctly answering 3 risk interpretation questions (odds ratio = 2.5, 95% confidence interval = 1.5-4.0, P < 0.001) compared to the text-only format. These findings were similar to those of previous studies carried out in the general population. Neither framing information as relative compared to absolute risk nor the interaction between graphic image and relative risk presentation was associated with risk interpretation. One type of graphic image was associated with increased understanding of risk in a small sample of American Indian adults. The authors recommend further investigation of the effectiveness of other types of graphic displays for conveying health risk information to this population.

  17. Development of Combinatorial Methods for Alloy Design and Optimization

    SciTech Connect

    Pharr, George M.; George, Easo P.; Santella, Michael L

    2005-07-01

    The primary goal of this research was to develop a comprehensive methodology for designing and optimizing metallic alloys by combinatorial principles. Because conventional techniques for alloy preparation are unavoidably restrictive in the range of alloy composition that can be examined, combinatorial methods promise to significantly reduce the time, energy, and expense needed for alloy design. Combinatorial methods can be developed not only to optimize existing alloys, but to explore and develop new ones as well. The scientific approach involved fabricating an alloy specimen with a continuous distribution of binary and ternary alloy compositions across its surface--an ''alloy library''--and then using spatially resolved probing techniques to characterize its structure, composition, and relevant properties. The three specific objectives of the project were: (1) to devise means by which simple test specimens with a library of alloy compositions spanning the range interest can be produced; (2) to assess how well the properties of the combinatorial specimen reproduce those of the conventionally processed alloys; and (3) to devise screening tools which can be used to rapidly assess the important properties of the alloys. As proof of principle, the methodology was applied to the Fe-Ni-Cr ternary alloy system that constitutes many commercially important materials such as stainless steels and the H-series and C-series heat and corrosion resistant casting alloys. Three different techniques were developed for making alloy libraries: (1) vapor deposition of discrete thin films on an appropriate substrate and then alloying them together by solid-state diffusion; (2) co-deposition of the alloying elements from three separate magnetron sputtering sources onto an inert substrate; and (3) localized melting of thin films with a focused electron-beam welding system. Each of the techniques was found to have its own advantages and disadvantages. A new and very powerful technique for

  18. Medicare calibration of the clinically detailed risk information system for cost.

    PubMed

    Kapur, Kanika; Tseng, Chien-Wen; Rastegar, Afshin; Carter, Grace M; Keeler, Emmett

    2003-01-01

    The clinically detailed risk information system for cost (CD-RISC) contains definitions for several hundred severity-adjusted conditions that can be used to predict future health care costs. We develop a prospective Medicare CD-RISC model using a 5-percent sample of Medicare beneficiaries and data that contain 1996 diagnostic information and 1997 annualized costs. The CD-RISC model has a hierarchical structure that implies that only the most expensive condition-severity variable within a body system affects payments. This minimizes incentives to game the system by entering multiple related codes for the same condition. The R2 for the CD-RISC model is 11 percent.

  19. Using web-based familial risk information for diabetes prevention: a randomized controlled trial.

    PubMed

    Wijdenes, Miranda; Henneman, Lidewij; Qureshi, Nadeem; Kostense, Piet J; Cornel, Martina C; Timmermans, Danielle R M

    2013-05-17

    It has been suggested that family history information may be effective in motivating people to adopt health promoting behaviour. The aim was to determine if diabetic familial risk information by using a web-based tool leads to improved self-reported risk-reducing behaviour among individuals with a diabetic family history, without causing false reassurance among those without a family history. An online sample of 1,174 healthy adults aged 35-65 years with a BMI ≥ 25 was randomized into two groups receiving an online diabetes risk assessment. Both arms received general tailored diabetes prevention information, whilst the intervention arm also received familial risk information after completing a detailed family history questionnaire. Separate analysis was performed for four groups (family history group: 286 control versus 288 intervention group; no family history: 269 control versus 266 intervention group). Primary outcomes were self-reported behavioural outcomes: fat intake, physical activity, and attitudes towards diabetes testing. Secondary outcomes were illness and risk perceptions. For individuals at familial risk there was no overall intervention effect on risk-reducing behaviour after three months, except for a decrease in self-reported saturated fat intake among low-educated individuals (Beta (b) -1.01, 95% CI -2.01 to 0.00). Familial risk information resulted in a decrease of diabetes risk worries (b -0.21, -0.40 to -0.03). For individuals without family history no effect was found on risk-reducing behaviour and perceived risk. A detailed family history assessment resulted in a greater percentage of individuals reporting a familial risk for diabetes compared to a simple enquiry. Web-based familial risk information reduced worry related to diabetes risk and decreased saturated fat intake of those at greatest need of preventative care. However, the intervention was not effective for the total study population on improving risk-reducing behaviour. The

  20. Consumers' preferences for the communication of risk information in drug advertising.

    PubMed

    Davis, Joel J

    2007-01-01

    Research was conducted to identify consumers' preferences regarding the form, content, and placement of drug side-effect information in direct-to-consumer (DTC) advertising. Specific questions explored preferences for the presence or absence of numeric information, the use of placebo and discontinuation groups as a context for understanding drug risk, the sequence in which side effects are presented, and the placement of side-effect statements on DTC Web sites. Consumers prefer detailed, readily accessible risk information--preferences that are a major departure from current advertiser practices and from what current and proposed Food and Drug Administration (FDA) regulations require.

  1. Parametric design of a Francis turbine runner by means of a three-dimensional inverse design method

    NASA Astrophysics Data System (ADS)

    Daneshkah, K.; Zangeneh, M.

    2010-08-01

    The present paper describes the parametric design of a Francis turbine runner. The runner geometry is parameterized by means of a 3D inverse design method, while CFD analyses were performed to assess the hydrodymanic and suction performance of different design configurations that were investigated. An initial runner design was first generated and used as baseline for parametric study. The effects of several design parameter, namely stacking condition and blade loading was then investigated in order to determine their effect on the suction performance. The use of blade parameterization using the inverse method lead to a major advantage for design of Francis turbine runners, as the three-dimensional blade shape is describe by parameters that closely related to the flow field namely blade loading and stacking condition that have a direct impact on the hydrodynamics of the flow field. On the basis of this study, an optimum configuration was designed which results in a cavitation free flow in the runner, while maintaining a high level of hydraulic efficiency. The paper highlights design guidelines for application of inverse design method to Francis turbine runners. The design guidelines have a general validity and can be used for similar design applications since they are based on flow field analyses and on hydrodynamic design parameters.

  2. A new method for designing dual foil electron beam forming systems. I. Introduction, concept of the method

    NASA Astrophysics Data System (ADS)

    Adrich, Przemysław

    2016-05-01

    In Part I of this work existing methods and problems in dual foil electron beam forming system design are presented. On this basis, a new method of designing these systems is introduced. The motivation behind this work is to eliminate the shortcomings of the existing design methods and improve overall efficiency of the dual foil design process. The existing methods are based on approximate analytical models applied in an unrealistically simplified geometry. Designing a dual foil system with these methods is a rather labor intensive task as corrections to account for the effects not included in the analytical models have to be calculated separately and accounted for in an iterative procedure. To eliminate these drawbacks, the new design method is based entirely on Monte Carlo modeling in a realistic geometry and using physics models that include all relevant processes. In our approach, an optimal configuration of the dual foil system is found by means of a systematic, automatized scan of the system performance in function of parameters of the foils. The new method, while being computationally intensive, minimizes the involvement of the designer and considerably shortens the overall design time. The results are of high quality as all the relevant physics and geometry details are naturally accounted for. To demonstrate the feasibility of practical implementation of the new method, specialized software tools were developed and applied to solve a real life design problem, as described in Part II of this work.

  3. Application of optimization methods to helicopter rotor blade design

    NASA Technical Reports Server (NTRS)

    Chattopadhyay, A.; Walsh, J. L.

    1990-01-01

    A procedure for the minimum weight design of helicopter rotor blades with constraints on multiple coupled flap-lag natural frequencies, autorotational inertia, and centrifugal stress is presented. Optimum designs are obtained for blades with both rectangular and tapered planforms and are compared within a reference blade. The effects of higher-frequency constraints and stress constraints on the optimum blade designs are assessed. The results indicate that there is an increase in blade weight and a significant change in the design variable distributions with an increase in the number of frequency constraints. The inclusion of stress constraints has different effects on the wall thickness distributions of rectangular and tapered blades, but tends to increase the magnitude of the nonstructural segment weight distributions for both blade types.

  4. Third order TRANSPORT with MAD (Methodical Accelerator Design) input

    SciTech Connect

    Carey, D.C.

    1988-09-20

    This paper describes computer-aided design codes for particle accelerators. Among the topics discussed are: input beam description; parameters and algebraic expressions; the physical elements; beam lines; operations; and third-order transfer matrix. (LSP)

  5. Outline of Methods for Design of Superconducting Turbogenerators,

    DTIC Science & Technology

    1983-08-18

    basic design magnitudes of superconducting gene- rators on the basis of a synthesis of the results of analyses of individual phenomena. Description of...to a machine with the design envisioned for this type of converter in the output range 0.3 to 3 GVA 161. Fig. 1 shows the basic elements of the...electromagnetic system and their mutual arrangement. The main purpose of using the algorithm is the 2 determination of basic geometric dimensions which

  6. Development of panel methods for subsonic analysis and design

    NASA Technical Reports Server (NTRS)

    Bristow, D. R.

    1980-01-01

    Two computer programs, developed for subsonic inviscid analysis and design are described. The first solves arbitrary mixed analysis design problems for multielement airfoils in two dimensional flow. The second calculates the pressure distribution for arbitrary lifting or nonlifting three dimensional configurations. In each program, inviscid flow is modelled by using distributed source doublet singularities on configuration surface panels. Numerical formulations and representative solutions are presented for the programs.

  7. An On-Board Diagnosis Logic and Its Design Method

    NASA Astrophysics Data System (ADS)

    Hiratsuka, Satoshi; Fusaoka, Akira

    In this paper, we propose a design methodology for on-board diagnosis engine of embedded systems. A boolean function for diagnosis circuit can be mechanically designed from the system dynamics given by the linear differential equation if it is observable, and also if the relation is given between the set of abnormal physical parameters and the faulty part. The size of diagnosis circuit is not so large that it can be implemented in FPGA or fabricated in a simple chip.

  8. Aircraft design for mission performance using nonlinear multiobjective optimization methods

    NASA Technical Reports Server (NTRS)

    Dovi, Augustine R.; Wrenn, Gregory A.

    1990-01-01

    A new technique which converts a constrained optimization problem to an unconstrained one where conflicting figures of merit may be simultaneously considered was combined with a complex mission analysis system. The method is compared with existing single and multiobjective optimization methods. A primary benefit from this new method for multiobjective optimization is the elimination of separate optimizations for each objective, which is required by some optimization methods. A typical wide body transport aircraft is used for the comparative studies.

  9. A Preliminary Rubric Design to Evaluate Mixed Methods Research

    ERIC Educational Resources Information Center

    Burrows, Timothy J.

    2013-01-01

    With the increase in frequency of the use of mixed methods, both in research publications and in externally funded grants there are increasing calls for a set of standards to assess the quality of mixed methods research. The purpose of this mixed methods study was to conduct a multi-phase analysis to create a preliminary rubric to evaluate mixed…

  10. A Preliminary Rubric Design to Evaluate Mixed Methods Research

    ERIC Educational Resources Information Center

    Burrows, Timothy J.

    2013-01-01

    With the increase in frequency of the use of mixed methods, both in research publications and in externally funded grants there are increasing calls for a set of standards to assess the quality of mixed methods research. The purpose of this mixed methods study was to conduct a multi-phase analysis to create a preliminary rubric to evaluate mixed…

  11. FIRE SAFETY IN NUCLEAR POWER PLANTS: A RISK-INFORMED AND PERFORMANCE-BASED APPROACH

    SciTech Connect

    AZARM,M.A.; TRAVIS,R.J.

    1999-11-14

    The consideration of risk in regulatory decision-making has long been a part of NRC's policy and practice. Initially, these considerations were qualitative and were based on risk insights. The early regulations relied on good practices, past insights, and accepted standards. As a result, most NRC regulations were prescriptive and were applied uniformly to all areas within the regulatory scope. Risk technology is changing regulations by prioritizing the areas within regulatory scope based on risk, thereby focusing on the risk-important areas. Performance technology, on the other hand, is changing the regulations by allowing requirements to be adjusted based on the specific performance expected and manifested, rather than a prior prescriptive requirement. Consistent with the objectives of risk-informed and performance-based regulatory requirements, BNL evaluated the feasibility of applying risk- and performance-technologies to modifying NRC's current regulations on fire protection for nuclear power plants. This feasibility study entailed several case studies (trial applications). This paper describes the results of two of them. Besides the case studies, the paper discusses an overall evaluation of methodologies for fire-risk analysis to support the risk-informed regulation. It identifies some current shortcomings and proposes some near-term solutions.

  12. Developing an Approach to Prioritize River Restoration using Data Extracted from Flood Risk Information System Databases.

    NASA Astrophysics Data System (ADS)

    Vimal, S.; Tarboton, D. G.; Band, L. E.; Duncan, J. M.; Lovette, J. P.; Corzo, G.; Miles, B.

    2015-12-01

    Prioritizing river restoration requires information on river geometry. In many states in the US detailed river geometry has been collected for floodplain mapping and is available in Flood Risk Information Systems (FRIS). In particular, North Carolina has, for its 100 Counties, developed a database of numerous HEC-RAS models which are available through its Flood Risk Information System (FRIS). These models that include over 260 variables were developed and updated by numerous contractors. They contain detailed surveyed or LiDAR derived cross-sections and modeled flood extents for different extreme event return periods. In this work, over 4700 HEC-RAS models' data was integrated and upscaled to utilize detailed cross-section information and 100-year modelled flood extent information to enable river restoration prioritization for the entire state of North Carolina. We developed procedures to extract geomorphic properties such as entrenchment ratio, incision ratio, etc. from these models. Entrenchment ratio quantifies the vertical containment of rivers and thereby their vulnerability to flooding and incision ratio quantifies the depth per unit width. A map of entrenchment ratio for the whole state was derived by linking these model results to a geodatabase. A ranking of highly entrenched counties enabling prioritization for flood allowance and mitigation was obtained. The results were shared through HydroShare and web maps developed for their visualization using Google Maps Engine API.

  13. Flexible Backbone Methods for Predicting and Designing Peptide Specificity.

    PubMed

    Ollikainen, Noah

    2017-01-01

    Protein-protein interactions play critical roles in essentially every cellular process. These interactions are often mediated by protein interaction domains that enable proteins to recognize their interaction partners, often by binding to short peptide motifs. For example, PDZ domains, which are among the most common protein interaction domains in the human proteome, recognize specific linear peptide sequences that are often at the C-terminus of other proteins. Determining the set of peptide sequences that a protein interaction domain binds, or it's "peptide specificity," is crucial for understanding its cellular function, and predicting how mutations impact peptide specificity is important for elucidating the mechanisms underlying human diseases. Moreover, engineering novel cellular functions for synthetic biology applications, such as the biosynthesis of biofuels or drugs, requires the design of protein interaction specificity to avoid crosstalk with native metabolic and signaling pathways. The ability to accurately predict and design protein-peptide interaction specificity is therefore critical for understanding and engineering biological function. One approach that has recently been employed toward accomplishing this goal is computational protein design. This chapter provides an overview of recent methodological advances in computational protein design and highlights examples of how these advances can enable increased accuracy in predicting and designing peptide specificity.

  14. Multiple methods integration for structural mechanics analysis and design

    NASA Technical Reports Server (NTRS)

    Housner, J. M.; Aminpour, M. A.

    1991-01-01

    A new research area of multiple methods integration is proposed for joining diverse methods of structural mechanics analysis which interact with one another. Three categories of multiple methods are defined: those in which a physical interface are well defined; those in which a physical interface is not well-defined, but selected; and those in which the interface is a mathematical transformation. Two fundamental integration procedures are presented that can be extended to integrate various methods (e.g., finite elements, Rayleigh Ritz, Galerkin, and integral methods) with one another. Since the finite element method will likely be the major method to be integrated, its enhanced robustness under element distortion is also examined and a new robust shell element is demonstrated.

  15. Statistical Methods for Rapid Aerothermal Analysis and Design Technology

    NASA Technical Reports Server (NTRS)

    Morgan, Carolyn; DePriest, Douglas; Thompson, Richard (Technical Monitor)

    2002-01-01

    The cost and safety goals for NASA's next generation of reusable launch vehicle (RLV) will require that rapid high-fidelity aerothermodynamic design tools be used early in the design cycle. To meet these requirements, it is desirable to establish statistical models that quantify and improve the accuracy, extend the applicability, and enable combined analyses using existing prediction tools. The research work was focused on establishing the suitable mathematical/statistical models for these purposes. It is anticipated that the resulting models can be incorporated into a software tool to provide rapid, variable-fidelity, aerothermal environments to predict heating along an arbitrary trajectory. This work will support development of an integrated design tool to perform automated thermal protection system (TPS) sizing and material selection.

  16. A design method for an intuitive web site

    SciTech Connect

    Quinniey, M.L.; Diegert, K.V.; Baca, B.G.; Forsythe, J.C.; Grose, E.

    1999-11-03

    The paper describes a methodology for designing a web site for human factor engineers that is applicable for designing a web site for a group of people. Many web pages on the World Wide Web are not organized in a format that allows a user to efficiently find information. Often the information and hypertext links on web pages are not organized into intuitive groups. Intuition implies that a person is able to use their knowledge of a paradigm to solve a problem. Intuitive groups are categories that allow web page users to find information by using their intuition or mental models of categories. In order to improve the human factors engineers efficiency for finding information on the World Wide Web, research was performed to develop a web site that serves as a tool for finding information effectively. The paper describes a methodology for designing a web site for a group of people who perform similar task in an organization.

  17. Approximation methods for combined thermal/structural design

    NASA Technical Reports Server (NTRS)

    Haftka, R. T.; Shore, C. P.

    1979-01-01

    Two approximation concepts for combined thermal/structural design are evaluated. The first concept is an approximate thermal analysis based on the first derivatives of structural temperatures with respect to design variables. Two commonly used first-order Taylor series expansions are examined. The direct and reciprocal expansions are special members of a general family of approximations, and for some conditions other members of that family of approximations are more accurate. Several examples are used to compare the accuracy of the different expansions. The second approximation concept is the use of critical time points for combined thermal and stress analyses of structures with transient loading conditions. Significant time savings are realized by identifying critical time points and performing the stress analysis for those points only. The design of an insulated panel which is exposed to transient heating conditions is discussed.

  18. A method for designing robust multivariable feedback systems

    NASA Technical Reports Server (NTRS)

    Milich, David Albert; Athans, Michael; Valavani, Lena; Stein, Gunter

    1988-01-01

    A new methodology is developed for the synthesis of linear, time-invariant (LTI) controllers for multivariable LTI systems. The aim is to achieve stability and performance robustness of the feedback system in the presence of multiple unstructured uncertainty blocks; i.e., to satisfy a frequency-domain inequality in terms of the structured singular value. The design technique is referred to as the Causality Recovery Methodology (CRM). Starting with an initial (nominally) stabilizing compensator, the CRM produces a closed-loop system whose performance-robustness is at least as good as, and hopefully superior to, that of the original design. The robustness improvement is obtained by solving an infinite-dimensional, convex optimization program. A finite-dimensional implementation of the CRM was developed, and it was applied to a multivariate design example.

  19. Computational RNA secondary structure design: empirical complexity and improved methods

    PubMed Central

    Aguirre-Hernández, Rosalía; Hoos, Holger H; Condon, Anne

    2007-01-01

    Background We investigate the empirical complexity of the RNA secondary structure design problem, that is, the scaling of the typical difficulty of the design task for various classes of RNA structures as the size of the target structure is increased. The purpose of this work is to understand better the factors that make RNA structures hard to design for existing, high-performance algorithms. Such understanding provides the basis for improving the performance of one of the best algorithms for this problem, RNA-SSD, and for characterising its limitations. Results To gain insights into the practical complexity of the problem, we present a scaling analysis on random and biologically motivated structures using an improved version of the RNA-SSD algorithm, and also the RNAinverse algorithm from the Vienna package. Since primary structure constraints are relevant for designing RNA structures, we also investigate the correlation between the number and the location of the primary structure constraints when designing structures and the performance of the RNA-SSD algorithm. The scaling analysis on random and biologically motivated structures supports the hypothesis that the running time of both algorithms scales polynomially with the size of the structure. We also found that the algorithms are in general faster when constraints are placed only on paired bases in the structure. Furthermore, we prove that, according to the standard thermodynamic model, for some structures that the RNA-SSD algorithm was unable to design, there exists no sequence whose minimum free energy structure is the target structure. Conclusion Our analysis helps to better understand the strengths and limitations of both the RNA-SSD and RNAinverse algorithms, and suggests ways in which the performance of these algorithms can be further improved. PMID:17266771

  20. Advanced 3D inverse method for designing turbomachine blades

    SciTech Connect

    Dang, T.

    1995-10-01

    To meet the goal of 60% plant-cycle efficiency or better set in the ATS Program for baseload utility scale power generation, several critical technologies need to be developed. One such need is the improvement of component efficiencies. This work addresses the issue of improving the performance of turbo-machine components in gas turbines through the development of an advanced three-dimensional and viscous blade design system. This technology is needed to replace some elements in current design systems that are based on outdated technology.

  1. [Drug design ideas and methods of Chinese herb prescriptions].

    PubMed

    Ren, Jun-guo; Liu, Jian-xun

    2015-09-01

    The new drug of Chinese herbal prescription, which is the best carrier for the syndrome differentiation and treatment of Chinese medicine and is the main form of the new drug research and development, plays a very important role in the new drug research and development. Although there are many sources of the prescriptions, whether it can become a new drug, the necessity, rationality and science of the prescriptions are the key to develop the new drug. In this article, aiming at the key issues in prescriptions design, the source, classification, composition design of new drug of Chinese herbal prescriptions are discussed, and provide a useful reference for research and development of new drugs.

  2. Prevalence of Mixed-Methods Sampling Designs in Social Science Research

    ERIC Educational Resources Information Center

    Collins, Kathleen M. T.

    2006-01-01

    The purpose of this mixed-methods study was to document the prevalence of sampling designs utilised in mixed-methods research and to examine the interpretive consistency between interpretations made in mixed-methods studies and the sampling design used. Classification of studies was based on a two-dimensional mixed-methods sampling model. This…

  3. An efficient multilevel optimization method for engineering design

    NASA Technical Reports Server (NTRS)

    Vanderplaats, G. N.; Yang, Y. J.; Kim, D. S.

    1988-01-01

    An efficient multilevel deisgn optimization technique is presented. The proposed method is based on the concept of providing linearized information between the system level and subsystem level optimization tasks. The advantages of the method are that it does not require optimum sensitivities, nonlinear equality constraints are not needed, and the method is relatively easy to use. The disadvantage is that the coupling between subsystems is not dealt with in a precise mathematical manner.

  4. Preliminary Axial Flow Turbine Design and Off-Design Performance Analysis Methods for Rotary Wing Aircraft Engines. Part 1; Validation

    NASA Technical Reports Server (NTRS)

    Chen, Shu-cheng, S.

    2009-01-01

    For the preliminary design and the off-design performance analysis of axial flow turbines, a pair of intermediate level-of-fidelity computer codes, TD2-2 (design; reference 1) and AXOD (off-design; reference 2), are being evaluated for use in turbine design and performance prediction of the modern high performance aircraft engines. TD2-2 employs a streamline curvature method for design, while AXOD approaches the flow analysis with an equal radius-height domain decomposition strategy. Both methods resolve only the flows in the annulus region while modeling the impact introduced by the blade rows. The mathematical formulations and derivations involved in both methods are documented in references 3, 4 for TD2-2) and in reference 5 (for AXOD). The focus of this paper is to discuss the fundamental issues of applicability and compatibility of the two codes as a pair of companion pieces, to perform preliminary design and off-design analysis for modern aircraft engine turbines. Two validation cases for the design and the off-design prediction using TD2-2 and AXOD conducted on two existing high efficiency turbines, developed and tested in the NASA/GE Energy Efficient Engine (GE-E3) Program, the High Pressure Turbine (HPT; two stages, air cooled) and the Low Pressure Turbine (LPT; five stages, un-cooled), are provided in support of the analysis and discussion presented in this paper.

  5. Convergence of controllers designed using state space methods

    NASA Technical Reports Server (NTRS)

    Morris, K. A.

    1991-01-01

    The convergence of finite dimensional controllers for infinite dimensional systems designed using approximations is examined. Stable coprime factorization theory is used to show that under the standard assumptions of uniform stabilizability/detectability, the controllers stabilize the original system for large enough model order. The controllers converge uniformly to an infinite dimensional controller, as does the closed loop response.

  6. Active Learning Methods and Technology: Strategies for Design Education

    ERIC Educational Resources Information Center

    Coorey, Jillian

    2016-01-01

    The demands in higher education are on the rise. Charged with teaching more content, increased class sizes and engaging students, educators face numerous challenges. In design education, educators are often torn between the teaching of technology and the teaching of theory. Learning the formal concepts of hierarchy, contrast and space provide the…

  7. A Prospective Method to Guide Small Molecule Drug Design

    ERIC Educational Resources Information Center

    Johnson, Alan T.

    2015-01-01

    At present, small molecule drug design follows a retrospective path when considering what analogs are to be made around a current hit or lead molecule with the focus often on identifying a compound with higher intrinsic potency. What this approach overlooks is the simultaneous need to also improve the physicochemical (PC) and pharmacokinetic (PK)…

  8. A Prospective Method to Guide Small Molecule Drug Design

    ERIC Educational Resources Information Center

    Johnson, Alan T.

    2015-01-01

    At present, small molecule drug design follows a retrospective path when considering what analogs are to be made around a current hit or lead molecule with the focus often on identifying a compound with higher intrinsic potency. What this approach overlooks is the simultaneous need to also improve the physicochemical (PC) and pharmacokinetic (PK)…

  9. Improved Methods for Classification, Prediction and Design of Antimicrobial Peptides

    PubMed Central

    Wang, Guangshun

    2015-01-01

    Peptides with diverse amino acid sequences, structures and functions are essential players in biological systems. The construction of well-annotated databases not only facilitates effective information management, search and mining, but also lays the foundation for developing and testing new peptide algorithms and machines. The antimicrobial peptide database (APD) is an original construction in terms of both database design and peptide entries. The host defense antimicrobial peptides (AMPs) registered in the APD cover the five kingdoms (bacteria, protists, fungi, plants, and animals) or three domains of life (bacteria, archaea, and eukaryota). This comprehensive database (http://aps.unmc.edu/AP) provides useful information on peptide discovery timeline, nomenclature, classification, glossary, calculation tools, and statistics. The APD enables effective search, prediction, and design of peptides with antibacterial, antiviral, antifungal, antiparasitic, insecticidal, spermicidal, anticancer activities, chemotactic, immune modulation, or anti-oxidative properties. A universal classification scheme is proposed herein to unify innate immunity peptides from a variety of biological sources. As an improvement, the upgraded APD makes predictions based on the database-defined parameter space and provides a list of the sequences most similar to natural AMPs. In addition, the powerful pipeline design of the database search engine laid a solid basis for designing novel antimicrobials to combat resistant superbugs, viruses, fungi or parasites. This comprehensive AMP database is a useful tool for both research and education. PMID:25555720

  10. Library Design Analysis Using Post-Occupancy Evaluation Methods.

    ERIC Educational Resources Information Center

    James, Dennis C.; Stewart, Sharon L.

    1995-01-01

    Presents findings of a user-based study of the interior of Rodger's Science and Engineering Library at the University of Alabama. Compared facility evaluations from faculty, library staff, and graduate and undergraduate students. Features evaluated include: acoustics, aesthetics, book stacks, design, finishes/materials, furniture, lighting,…

  11. Active Learning Methods and Technology: Strategies for Design Education

    ERIC Educational Resources Information Center

    Coorey, Jillian

    2016-01-01

    The demands in higher education are on the rise. Charged with teaching more content, increased class sizes and engaging students, educators face numerous challenges. In design education, educators are often torn between the teaching of technology and the teaching of theory. Learning the formal concepts of hierarchy, contrast and space provide the…

  12. Overview of control design methods for smart structural system

    NASA Astrophysics Data System (ADS)

    Rao, Vittal S.; Sana, Sridhar

    2001-08-01

    Smart structures are a result of effective integration of control system design and signal processing with the structural systems to maximally utilize the new advances in materials for structures, actuation and sensing to obtain the best performance for the application at hand. The research in smart structures is constantly driving towards attaining self adaptive and diagnostic capabilities that biological systems possess. This has been manifested in the number of successful applications in many areas of engineering such as aerospace, civil and automotive systems. Instrumental in the development of such systems are smart materials such as piezo-electric, shape memory alloys, electrostrictive, magnetostrictive and fiber-optic materials and various composite materials for use as actuators, sensors and structural members. The need for development of control systems that maximally utilize the smart actuators and sensing materials to design highly distributed and highly adaptable controllers has spurred research in the area of smart structural modeling, identification, actuator/sensor design and placement, control systems design such as adaptive and robust controllers with new tools such a neural networks, fuzzy logic, genetic algorithms, linear matrix inequalities and electronics for controller implementation such as analog electronics, micro controllers, digital signal processors (DSPs) and application specific integrated circuits (ASICs) such field programmable gate arrays (FPGAs) and Multichip modules (MCMs) etc. In this paper, we give a brief overview of the state of control in smart structures. Different aspects of the development of smart structures such as applications, technology and theoretical advances especially in the area of control systems design and implementation will be covered.

  13. Optimal reliability design method for remote solar systems

    NASA Astrophysics Data System (ADS)

    Suwapaet, Nuchida

    A unique optimal reliability design algorithm is developed for remote communication systems. The algorithm deals with either minimizing an unavailability of the system within a fixed cost or minimizing the cost of the system with an unavailability constraint. The unavailability of the system is a function of three possible failure occurrences: individual component breakdown, solar energy deficiency (loss of load probability), and satellite/radio transmission loss. The three mathematical models of component failure, solar power failure, transmission failure are combined and formulated as a nonlinear programming optimization problem with binary decision variables, such as number and type (or size) of photovoltaic modules, batteries, radios, antennas, and controllers. Three possible failures are identified and integrated in computer algorithm to generate the parameters for the optimization algorithm. The optimization algorithm is implemented with a branch-and-bound technique solution in MS Excel Solver. The algorithm is applied to a case study design for an actual system that will be set up in remote mountainous areas of Peru. The automated algorithm is verified with independent calculations. The optimal results from minimizing the unavailability of the system with the cost constraint case and minimizing the total cost of the system with the unavailability constraint case are consistent with each other. The tradeoff feature in the algorithm allows designers to observe results of 'what-if' scenarios of relaxing constraint bounds, thus obtaining the most benefit from the optimization process. An example of this approach applied to an existing communication system in the Andes shows dramatic improvement in reliability for little increase in cost. The algorithm is a real design tool, unlike other existing simulation design tools. The algorithm should be useful for other stochastic systems where component reliability, random supply and demand, and communication are

  14. Designing a Science Methods Course for Early Childhood Preservice Teachers

    ERIC Educational Resources Information Center

    Akerson, Valarie L.

    2004-01-01

    Preparing early childhood (K-3) teachers to teach science presents special challenges for the science methods instructor. Early childhood preservice teachers typically come to the methods classroom with little science content knowledge; they also lack confidence in their own abilities to teach science. This paper presents a theoretical background,…

  15. Applications of Genetic Methods to NASA Design and Operations Problems

    NASA Technical Reports Server (NTRS)

    Laird, Philip D.

    1996-01-01

    We review four recent NASA-funded applications in which evolutionary/genetic methods are important. In the process we survey: the kinds of problems being solved today with these methods; techniques and tools used; problems encountered; and areas where research is needed. The presentation slides are annotated briefly at the top of each page.

  16. Design and ergonomics. Methods for integrating ergonomics at hand tool design stage.

    PubMed

    Marsot, Jacques; Claudon, Laurent

    2004-01-01

    As a marked increase in the number of musculoskeletal disorders was noted in many industrialized countries and more specifically in companies that require the use of hand tools, the French National Research and Safety Institute (INRS) launched in 1999 a research project on the topic of integrating ergonomics into hand tool design, and more particularly to a design of a boning knife. After a brief recall of the difficulties of integrating ergonomics at the design stage, the present paper shows how 3 design methodological tools--Functional Analysis, Quality Function Deployment and TRIZ--have been applied to the design of a boning knife. Implementation of these tools enabled us to demonstrate the extent to which they are capable of responding to the difficulties of integrating ergonomics into product design.

  17. Consumers' Kansei Needs Clustering Method for Product Emotional Design Based on Numerical Design Structure Matrix and Genetic Algorithms

    PubMed Central

    Chen, Deng-kai; Gu, Rong; Gu, Yu-feng; Yu, Sui-huai

    2016-01-01

    Consumers' Kansei needs reflect their perception about a product and always consist of a large number of adjectives. Reducing the dimension complexity of these needs to extract primary words not only enables the target product to be explicitly positioned, but also provides a convenient design basis for designers engaging in design work. Accordingly, this study employs a numerical design structure matrix (NDSM) by parameterizing a conventional DSM and integrating genetic algorithms to find optimum Kansei clusters. A four-point scale method is applied to assign link weights of every two Kansei adjectives as values of cells when constructing an NDSM. Genetic algorithms are used to cluster the Kansei NDSM and find optimum clusters. Furthermore, the process of the proposed method is presented. The details of the proposed approach are illustrated using an example of electronic scooter for Kansei needs clustering. The case study reveals that the proposed method is promising for clustering Kansei needs adjectives in product emotional design. PMID:27630709

  18. Consumers' Kansei Needs Clustering Method for Product Emotional Design Based on Numerical Design Structure Matrix and Genetic Algorithms.

    PubMed

    Yang, Yan-Pu; Chen, Deng-Kai; Gu, Rong; Gu, Yu-Feng; Yu, Sui-Huai

    2016-01-01

    Consumers' Kansei needs reflect their perception about a product and always consist of a large number of adjectives. Reducing the dimension complexity of these needs to extract primary words not only enables the target product to be explicitly positioned, but also provides a convenient design basis for designers engaging in design work. Accordingly, this study employs a numerical design structure matrix (NDSM) by parameterizing a conventional DSM and integrating genetic algorithms to find optimum Kansei clusters. A four-point scale method is applied to assign link weights of every two Kansei adjectives as values of cells when constructing an NDSM. Genetic algorithms are used to cluster the Kansei NDSM and find optimum clusters. Furthermore, the process of the proposed method is presented. The details of the proposed approach are illustrated using an example of electronic scooter for Kansei needs clustering. The case study reveals that the proposed method is promising for clustering Kansei needs adjectives in product emotional design.

  19. Design component method for sensitivity analysis of built-up structures

    NASA Technical Reports Server (NTRS)

    Choi, Kyung K.; Seong, Hwai G.

    1986-01-01

    A 'design component method' that provides a unified and systematic organization of design sensitivity analysis for built-up structures is developed and implemented. Both conventional design variables, such as thickness and cross-sectional area, and shape design variables of components of built-up structures are considered. It is shown that design of components of built-up structures can be characterized and system design sensitivity expressions obtained by simply adding contributions from each component. The method leads to a systematic organization of computations for design sensitivity analysis that is similar to the way in which computations are organized within a finite element code.

  20. The Hip Impact Protection Project: design and methods.

    PubMed

    Barton, Bruce A; Birge, Stanley J; Magaziner, Jay; Zimmerman, Sheryl; Ball, Linda; Brown, Kathleen M; Kiel, Douglas P

    2008-01-01

    Nearly 340,000 hip fractures occur each year in the U.S. With current demographic trends, the number of hip fractures is expected to double at least in the next 40 years. The Hip Impact Protection Project (HIP PRO) was designed to investigate the efficacy and safety of hip protectors in an elderly nursing home population. This paper describes the innovative clustered matched-pair research design used in HIP PRO to overcome the inherent limitations of clustered randomization. Three clinical centers recruited 37 nursing homes to participate in HIP PRO. They were randomized so that the participating residents in that home received hip protectors for either the right or left hip. Informed consent was obtained from either the resident or the resident's responsible party. The target sample size was 580 residents with replacement if they dropped out, had a hip fracture, or died. One of the advantages of the HIP PRO study design was that each resident was his/her own case and control, eliminating imbalances, and there was no confusion over which residents wore pads (or on which hip). Generalizability of the findings may be limited. Adherence was higher in this study than in other studies because of: (1) the use of a run-in period, (2) staff incentives, and (3) the frequency of adherence assessments. The use of a single pad is not analogous to pad use in the real world and may have caused unanticipated changes in behavior. Fall assessment was not feasible, limiting the ability to analyze fractures as a function of falls. Finally, hip protector designs continue to evolve so that the results generated using this pad may not be applicable to other pad designs. However, information about factors related to adherence will be useful for future studies. The clustered matched-pair study design avoided the major problem with previous cluster-randomized investigations of this question - unbalanced risk factors between the experimental group and the control group. Because each