WorldWideScience

Sample records for previous design problems

  1. Adolescents previously involved in Satanism experiencing mental health problems

    Directory of Open Access Journals (Sweden)

    H Heathcote

    1999-09-01

    Full Text Available No research has previously been done regarding the phenomenon of adolescents who have previously been involved in Satanism and who experience obstacles in their strive for mental health. Adolescents previously involved in Satanism present behavioral problems like aggressive outbursts, depression, “ psychosis” or suicide attempts, that could lead to suicide. In the phenomenonanalysis semi-structured, phenomenological interviews were performed with the respondents and their parents. The respondents were requested to write a naïve sketch about their life. After completion of the data-control, guidelines for nursing staff were set.

  2. Problem Based Game Design

    DEFF Research Database (Denmark)

    Reng, Lars; Schoenau-Fog, Henrik

    2011-01-01

    At Aalborg University’s department of Medialogy, we are utilizing the Problem Based Learning method to encourage students to solve game design problems by pushing the boundaries and designing innovative games. This paper is concerned with describing this method, how students employ it in various...... projects and how they learn to analyse, design, and develop for innovation by using it. We will present various cases to exemplify the approach and focus on how the method engages students and aspires for innovation in digital entertainment and games....

  3. Optimization of hydraulic machinery by exploiting previous successful designs

    Energy Technology Data Exchange (ETDEWEB)

    Kyriacou, S A; Giannakoglou, K C [National Technical University of Athens, Parallel CFD and Optimization Unit, PO Box 64069, Athens 15710 (Greece); Weissenberger, S; Grafenberger, P, E-mail: stelios.Kyriacou@gmail.co [Andritz HYDRO, RD, Lunzerstrasse 78, 4031 Linz (Austria)

    2010-08-15

    A design-optimization method for hydraulic machinery is proposed. Optimal designs are obtained using the appropriate CFD evaluation software driven by an evolutionary algorithm which is also assisted by artificial neural networks used as surrogate evaluation models or metamodels. As shown in a previous IAHR paper by the same authors, such an optimization method substantially reduces the CPU cost, since the metamodels can discard numerous non-promising candidate solutions generated during the evolution, at almost negligible CPU cost, without evaluating them by means of the costly CFD tool. The present paper extends the optimization method of the previous paper by making it capable to accommodate and exploit pieces of useful information archived during previous relevant successful designs. So, instead of parameterizing the geometry of the hydraulic machine components, which inevitably leads to many design variables, enough to slow down the design procedure, in the proposed method all new designs are expressed as weighted combinations of the archived ones. The archived designs act as the design space bases. The role of the optimization algorithms is to find the set (or sets, for more than one objectives, where the Pareto front of non-dominated solutions is sought) of weight values, corresponding to the hydraulic machine configuration(s) with optimal performance. Since the number of weights is much less that the number of design variables of the conventional shape parameterization, the design space dimension reduces and the CPU cost of the metamodel-assisted evolutionary algorithm is much lower. The design of a Francis runner is used to demonstrate the capabilities of the proposed method.

  4. Design Problems for Secondary Students

    Science.gov (United States)

    Jonassen, David H.

    2011-01-01

    Are there different kinds of design problems? Jonassen (2011) argued that problems vary in terms of structuredness, complexity, and context. On the structuredness and complexity continua, design problems tend to be the most ill-structured and complex. Brown and Chandrasekaran suggest that design problems may vary along a continuum from…

  5. Group Design Problems in Engineering Design Graphics.

    Science.gov (United States)

    Kelley, David

    2001-01-01

    Describes group design techniques used within the engineering design graphics sequence at Western Washington University. Engineering and design philosophies such as concurrent engineering place an emphasis on group collaboration for the solving of design problems. (Author/DDR)

  6. Leadership as a Design Problem

    Science.gov (United States)

    1977-10-01

    Organizational Behavior and Human Performance, 1975, U, 264-280. Bennis, W. G. Leadership theory and administrative behavior: The problem of authority...Administrative Science Quarterly, 1959, 4, 259-301^ Calder, B. J. An attribution theory of leadership . In B. Staw & G, Salancik (Eds.), New directions...REPORT NUMBER TR #1 2. GOVT ACCESSION NO 3. RECIPIENT’S CATALOG NUMBER 4. TITLE (and Sublllle) LEADERSHIP AS A DESIGN PROBLEM 5

  7. Engineering design problems of TFTR

    International Nuclear Information System (INIS)

    Lee, D.

    1977-01-01

    Design of the TFTR poses special engineering problems as a result of constraints posed by the physics requirements of the fusion experiments. The ratio of plasma major and minor radii and the associated magnetic field strength required to achieve desired plasma conditions, the required confinement time, the two-component plasma concept, the complications of providing shielding from the 14 MeV neutrons and the necessity to control the inventory of tritium fuel, all constitute problems which, often, in actuality, must be approached as materials problems. The complex, precision structures must satisfy various criteria, for example, low magnetic permeability, high electrical resistivity, resistance to neutron activation and high damage tolerance. Another constraint in the engineering design of TFTR is the requirement to optimize access to machine components for maintenance and repair. Many of the problems associated with accessibility have been resolved: the vacuum vessel has been designed as a ten-segment vessel; the igloo shielding of the machine is composed of interlocking blocks of boron-loaded concrete; the center column is designed in three segments. Current engineering emphasis is on finalizing design of the toroidal field coils, lower poloidal field coils, vacuum vessel liners and limiters and peripheral systems such as the vacuum pumping system and arrangement of diagnostics

  8. A New Lagrangian Relaxation Method Considering Previous Hour Scheduling for Unit Commitment Problem

    Science.gov (United States)

    Khorasani, H.; Rashidinejad, M.; Purakbari-Kasmaie, M.; Abdollahi, A.

    2009-08-01

    Generation scheduling is a crucial challenge in power systems especially under new environment of liberalization of electricity industry. A new Lagrangian relaxation method for unit commitment (UC) has been presented for solving generation scheduling problem. This paper focuses on the economical aspect of UC problem, while the previous hour scheduling as a very important issue is studied. In this paper generation scheduling of present hour has been conducted by considering the previous hour scheduling. The impacts of hot/cold start-up cost have been taken in to account in this paper. Case studies and numerical analysis presents significant outcomes while it demonstrates the effectiveness of the proposed method.

  9. Groin Problems in Male Soccer Players Are More Common Than Previously Reported.

    Science.gov (United States)

    Harøy, Joar; Clarsen, Ben; Thorborg, Kristian; Hölmich, Per; Bahr, Roald; Andersen, Thor Einar

    2017-05-01

    The majority of surveillance studies in soccer have used a time-loss injury definition, and many groin problems result from overuse, leading to gradually increasing pain and/or reduced performance without necessarily causing an absence from soccer training or match play. Thus, the magnitude of groin problems in soccer has probably been underestimated in previous studies based on traditional injury surveillance methods. To investigate the prevalence of groin problems among soccer players of both sexes and among male soccer players at different levels of play through a new surveillance method developed to capture acute and overuse problems. Descriptive epidemiology study. We registered groin problems during a 6-week period of match congestion using the Oslo Sports Trauma Research Center Overuse Injury Questionnaire. A total of 240 players from 15 teams across different levels of play and from both sexes were included, and they responded to the weekly questionnaire. We calculated the average weekly prevalence of all groin problems and substantial groin problems. Of the 240 players, 112 male players (59%) and 20 female players (45%) reported at least 1 episode of groin problems. The average weekly prevalence of any groin problem and substantial groin problem for all male players was 29% (range, 23%-32% across different levels) and 10% (7%-13%), respectively. Elite male players had an increased risk of experiencing groin problems (odds ratio: 3.1, 95% CI: 1.5-6.4, P = .03) compared with elite female players. There was no difference in the risk of experiencing groin problems among elite, subelite, and amateur male players. For substantial problems, there was no difference between elite male and elite female players or among levels of play for senior male soccer players. We found a high prevalence of groin problems among male soccer players during a period with match congestion. Time-loss definition as used in previous injury surveillance studies captured only one

  10. Allocation Problems and Market Design

    DEFF Research Database (Denmark)

    Smilgins, Aleksandrs

    The thesis contains six independent papers with a common theme: Allocation problems and market design. The first paper is concerned with fair allocation of risk capital where independent autonomous subunits have risky activities and together constitute the entity's total risk, whose associated risk......-to-one matching model by including a set of objects, such that a matching consists of two agents from disjoint sets, and an object. Agents' preference lists consist of all possible pairs of objects and agents from the other set, and thus contain important information about agent-object tradeoffs. The notion...

  11. Silverlight 4 Problem - Design - Solution

    CERN Document Server

    Lecrenski, Nick

    2010-01-01

    A hands-on guide to Microsoft's latest rich application development technology: Silverlight 4. Silverlight 4 is the newest version of the rich Internet application toolkit that provides support for .NET capabilities over the Internet. With this latest release of Silverlight, Microsoft has revolutionized the way that Web applications can be created. This book uses the popular ProblemDesign – Solution strategy to demonstrate how to harness the power and abilities of Silverlight 4 to add value to the overall user experience of a Web site. Using a Web site created by the author as a reference p

  12. Geoengineering as a design problem

    Energy Technology Data Exchange (ETDEWEB)

    Kravitz, Ben; MacMartin, Douglas G.; Wang, Hailong; Rasch, Philip J.

    2016-01-01

    Understanding the climate impacts of solar geoengineering is essential for evaluating its benefits and risks. Most previous simulations have prescribed a particular strategy and evaluated its modeled effects. Here we turn this approach around by first choosing example climate objectives and then designing a strategy to meet those objectives in climate models.

    There are four essential criteria for designing a strategy: (i) an explicit specification of the objectives, (ii) defining what climate forcing agents to modify so the objectives are met, (iii) a method for managing uncertainties, and (iv) independent verification of the strategy in an evaluation model.

    We demonstrate this design perspective through two multi-objective examples. First, changes in Arctic temperature and the position of tropical precipitation due to CO2 increases are offset by adjusting high-latitude insolation in each hemisphere independently. Second, three different latitude-dependent patterns of insolation are modified to offset CO2-induced changes in global mean temperature, interhemispheric temperature asymmetry, and the Equator-to-pole temperature gradient. In both examples, the "design" and "evaluation" models are state-of-the-art fully coupled atmosphere–ocean general circulation models.

  13. Groin Problems in Male Soccer Players Are More Common Than Previously Reported

    DEFF Research Database (Denmark)

    Harøy, Joar; Clarsen, Ben; Thorborg, Kristian

    2017-01-01

    BACKGROUND: The majority of surveillance studies in soccer have used a time-loss injury definition, and many groin problems result from overuse, leading to gradually increasing pain and/or reduced performance without necessarily causing an absence from soccer training or match play. Thus, the mag......BACKGROUND: The majority of surveillance studies in soccer have used a time-loss injury definition, and many groin problems result from overuse, leading to gradually increasing pain and/or reduced performance without necessarily causing an absence from soccer training or match play. Thus......, the magnitude of groin problems in soccer has probably been underestimated in previous studies based on traditional injury surveillance methods. PURPOSE: To investigate the prevalence of groin problems among soccer players of both sexes and among male soccer players at different levels of play through a new...... across different levels of play and from both sexes were included, and they responded to the weekly questionnaire. We calculated the average weekly prevalence of all groin problems and substantial groin problems. RESULTS: Of the 240 players, 112 male players (59%) and 20 female players (45%) reported...

  14. Problem formulation as a discursive design activity

    DEFF Research Database (Denmark)

    Hansen, Claus Thorp; Dorst, Kees; Andreasen, Mogens Myrup

    2009-01-01

    part of any engineering design education. Yet the assumptions behind the rational problem solving approach to design do not sit well with some of the experiences we have in design teaching and design practice. Problem formulation is one such area where we might have to look for a different way...... the intricacies of problem formulation in design. Key notions in design methodology, like ‘design problem’, ‘design solution’ and ‘ill-structuredness’ are reconsidered in this light. This directly leads to identifying further lines for investigation, and an agenda for design research....

  15. Comparison of Problem Solving from Engineering Design to Software Design

    DEFF Research Database (Denmark)

    Ahmed-Kristensen, Saeema; Babar, Muhammad Ali

    2012-01-01

    Observational studies of engineering design activities can inform the research community on the problem solving models that are employed by professional engineers. Design is defined as an ill-defined problem which includes both engineering design and software design, hence understanding problem s...

  16. Problem formulation as a discursive design activity

    DEFF Research Database (Denmark)

    Hansen, Claus Thorp; Dorst, Kees; Andreasen, Mogens Myrup

    2009-01-01

    In the design methodology literature, design is often described as a rational problem solving process. This approach has been very successful; it has lead to the creation of design process models, tools, methods and techniques. Design methods teaching along these lines has become an indispensable...... part of any engineering design education. Yet the assumptions behind the rational problem solving approach to design do not sit well with some of the experiences we have in design teaching and design practice. Problem formulation is one such area where we might have to look for a different way...

  17. Enhanced learning through design problems

    DEFF Research Database (Denmark)

    Jensen, Bogi Bech; Högberg, Stig; Jensen, Frida av Fløtum

    2012-01-01

    This paper describes a teaching method used in an electrical machines course, where the students learn about electrical machines by designing them. The aim of the course is not to teach design, albeit this is a side product, but rather to teach the fundamentals and the function of electrical...... machines through design. The teaching method is evaluated by a student questionnaire, designed to measure the quality and effectiveness of the teaching method. The results of the questionnaire conclusively show that this method labelled ‘learning through design’ is a very effective way of teaching...... a components-based course. This teaching method can easily be generalised and used in other courses....

  18. Reinventing the Wheel: Design and Problem Solving

    Science.gov (United States)

    Blasetti, Sean M.

    2010-01-01

    This article describes a design problem that not only takes students through the technological design process, but it also provides them with real-world problem-solving experience as it relates to the manufacturing and engineering fields. It begins with a scenario placing the student as a custom wheel designer for an automotive manufacturing…

  19. Comparison of Problem Solving from Engineering Design to Software Design

    DEFF Research Database (Denmark)

    Ahmed-Kristensen, Saeema; Babar, Muhammad Ali

    2012-01-01

    Observational studies of engineering design activities can inform the research community on the problem solving models that are employed by professional engineers. Design is defined as an ill-defined problem which includes both engineering design and software design, hence understanding problem...... solving models from other design domains is of interest to the engineering design community. For this paper an observational study of two software design sessions performed for the workshop on “Studying professional Software Design” is compared to analysis from engineering design. These findings provide...... useful insights of how software designers move from a problem domain to a solution domain and the commonalities between software designers’ and engineering designers’ design activities. The software designers were found to move quickly to a detailed design phase, employ co-.evolution and adopt...

  20. Comparison of Problem Solving from Engineering Design to Software Design

    DEFF Research Database (Denmark)

    Ahmed-Kristensen, Saeema; Babar, Muhammad Ali

    2012-01-01

    solving models from other design domains is of interest to the engineering design community. For this paper an observational study of two software design sessions performed for the workshop on “Studying professional Software Design” is compared to analysis from engineering design. These findings provide......Observational studies of engineering design activities can inform the research community on the problem solving models that are employed by professional engineers. Design is defined as an ill-defined problem which includes both engineering design and software design, hence understanding problem...... useful insights of how software designers move from a problem domain to a solution domain and the commonalities between software designers’ and engineering designers’ design activities. The software designers were found to move quickly to a detailed design phase, employ co-.evolution and adopt...

  1. 76 FR 59488 - Addition to the Identifying Information for an Individual Previously Designated Pursuant to...

    Science.gov (United States)

    2011-09-26

    ... information for the following individual who was previously designated pursuant to the Order: GRAJALES PUENTES...; Cedula No. 52455790 (Colombia) (individual) [SDNT] The listing now appears as follows: GRAJALES PUENTES...

  2. Problems of structural mechanics in nuclear design

    International Nuclear Information System (INIS)

    Patwardhan, V.M.; Kakodkar, Anil

    1975-01-01

    A very careful and detailed stress analysis of nuclear presure vessels and components is essential for ensuring the safety and integrity of nuclear power plants. The nuclear designer, therefore, relies heavily on structural mechanics for application of the most advanced stress analysis techniques to practical design problems. The paper reviews the inter-relation between structural mechanics and nuclear design and discusses a few of the specific structural mechanics problems faced by the nuclear designers in the Department of Atomic Energy, India. (author)

  3. On the content of design problems

    DEFF Research Database (Denmark)

    Hansen, Claus Thorp; Andreasen, Mogens Myrup

    2008-01-01

    To see designing as a rational problem solving activity has been the predominant understanding in design methodology literature. However, in a recent paper Dorst proposes seeing designing as a discursive activity, where a design problem is a paradoxical problem situation consisting of conflicting...... and teachable description of design problems. The result should be a productive contribution to designers working in industrial practice and to the teaching in this area....... discourses, and where the designer has to create a solution that transcends or connects the discourses. The authors see Dorst’s proposal as a valuable framework to build upon. We see a challenge to combine Dorst’s framework with existing concepts and methods in order to develop a new, operational...

  4. Teaching Problem Solving: An Instructional Design Strategy.

    Science.gov (United States)

    Ross, John A.; Maynes, Florence J.

    1983-01-01

    Instructional design strategy for improving problem solving is presented. The strategy entails selecting an appropriate domain of problem-solving tasks, learning hierarchies, teaching methods and assembling of learning materials, and designing teacher training and evaluation. Obstacles to be overcome and directions for future research are…

  5. Social and physical health of homeless adults previously treated for mental health problems.

    Science.gov (United States)

    Gelberg, L; Linn, L S

    1988-05-01

    A total of 529 homeless adults in Los Angeles County were surveyed to determine the relationship between their previous use of mental health services and their physical health status, utilization of medical services, personal habits affecting health, experience of injury and victimization, and perceived needs. Homeless adults with a previous psychiatric hospitalization were more likely to have experienced serious physical symptoms during the previous month than those who had used only outpatient mental health services or who had never used mental health services. They reported more reasons for not obtaining needed medical care, were more likely to obtained food from garbage cans, and had the least adequate personal hygiene. However, they did not differ from the other groups on most measures of nutrition, social relations, and financial status. The most frequently expressed needs of the homeless were for improved social relations, employment, shelter, and money.

  6. Problem and design drawing for solution of precision design drawing and machine design

    International Nuclear Information System (INIS)

    Heo, Gil

    1982-04-01

    The contents of this book are basic of design drawing, problem of machine design, problem of precision design drawing, problem of planar figure of sheet metal, design drawing for solution of machine design, design drawing for solution of precision design drawing and design drawing for planar figure of sheet metal. It tells of the problems and gives the solutions on precision design drawing and machine design.

  7. Mechanism design problems in carbon economics

    OpenAIRE

    Arava, Radhika; Narahari, Y; Bagchi, Deepak; Suresh, P; Subrahmanya, SV

    2010-01-01

    Reduction of carbon emissions is of paramount importance in the context of global warming and climate change. Countries and global companies are now engaged in understanding systematic ways of solving carbon economics problems, aimed ultimately at achieving well defined emission targets. This paper proposes mechanism design as an approach to solving carbon economics problems. The paper first introduces carbon economics issues in the world today and next focuses on carbon economics problems...

  8. Problem Solving Methods in Engineering Design

    DEFF Research Database (Denmark)

    Hartvig, Susanne C

    1999-01-01

    This short paper discusses typical engineering tasks and problem solving methods, based on a field study of engineering tasks at a Danish engineering firm. The field study has identified ten classes of design tasks and in this paper these classes are related to problem solving methods...

  9. An optimal design problem in wave propagation

    DEFF Research Database (Denmark)

    Bellido, J.C.; Donoso, Alberto

    2007-01-01

    We consider an optimal design problem in wave propagation proposed in Sigmund and Jensen (Roy. Soc. Lond. Philos. Trans. Ser. A 361:1001-1019, 2003) in the one-dimensional situation: Given two materials at our disposal with different elastic Young modulus and different density, the problem consists...

  10. Study of some physical aspects previous to design of an exponential experiment

    International Nuclear Information System (INIS)

    Caro, R.; Francisco, J. L. de

    1961-01-01

    This report presents the theoretical study of some physical aspects previous to the design of an exponential facility. The are: Fast and slow flux distribution in the multiplicative medium and in the thermal column, slowing down in the thermal column, geometrical distribution and minimum needed intensity of sources access channels and perturbations produced by possible variations in its position and intensity. (Author) 4 refs

  11. The Future of Design: Unframed Problem Solving in Design Education

    DEFF Research Database (Denmark)

    Friis, Silje Alberthe Kamille; Gelting, Anne Katrine Gøtzsche

    2016-01-01

    The present paper sets out to investigate the impact and significance of a 3rd semester course in design methods, complex problem solving, and cross-disciplinary collaboration to the students within six design disciplines as experienced by the students three years later. The course reflects a shift...... in focus from a design practice framed by outcome to open-ended problem solving. Data shows that some students draw a direct line between the course and later success, for instance in obtaining an internship, whereas others find it of little use and relevance to later practice. Existing design research...... and theory is applied to further understand how to motivate design students to engage in an expanded field of design practice. Findings indicate that students need help to disengage from identifying with a particular design discipline if they are to engage in complex problem solving with an open mindset...

  12. SOLVING GLOBAL PROBLEMS USING COLLABORATIVE DESIGN PROCESSES

    DEFF Research Database (Denmark)

    Lenau, Torben Anker; Mejborn, Christina Okai

    2011-01-01

    In this paper we argue that use of collaborative design processes is a powerful means of bringing together different stakeholders and generating ideas in complex design situations. The collaborative design process was used in a workshop with international participants where the goal was to propose...... new solutions that would help solve the global problem of sanitation. Lack of sanitation is a problem for 42% of the world’s population but it is also a taboo topic that only very few people will engage in. In the one-day workshop participants from very different areas came together and brought...

  13. Fractures around a previous fixation of proximal femur. A simple solution to a complex problem.

    Directory of Open Access Journals (Sweden)

    Fernando Manuel Bidolegui

    2016-05-01

    Full Text Available The number of hip fractures in the elderly growth with the increase in life expectancy. Therefore meet with a femur fractured, distal to a previously  implant fixation used in intertrochanteric femur fractures as dynamic hip screw or fixed angle plate, is not an uncommon scenario despite year mortality of hip fracture of 30 to 50%. Given this situation, we used a retrograde intramedullary nail associated with extracting screws percutaneously prior implant. We present 8 cases in patients with an average age of 85.6 years, 5 female and 3 male with a time from the proximal femur fixation to the  new fracture average 3.5 years. Will we track 36 months and we evaluated postoperative mobility and pain getting a consolidation of the fracture in all cases. We found this technique effective; capable of achieving stable fixation without adding morbidity due to the possibility of overlapping two implants decreasing the possibility of potential new interimplantes fracture.

  14. SOLVING GLOBAL PROBLEMS USING COLLABORATIVE DESIGN PROCESSES

    DEFF Research Database (Denmark)

    Lenau, Torben Anker; Mejborn, Christina Okai

    2011-01-01

    In this paper we argue that use of collaborative design processes is a powerful means of bringing together different stakeholders and generating ideas in complex design situations. The collaborative design process was used in a workshop with international participants where the goal was to propose...... forward proposed solutions for how to design, brand and make business models for how to solve aspects of the sanitation problem. The workshop showed that it was possible to work freely with such a taboo topic and that in particular the use of visualisation tools, i.e. drawing posters and building simple...

  15. Analysis of Feeder Bus Network Design and Scheduling Problems

    Directory of Open Access Journals (Sweden)

    Mohammad Hadi Almasi

    2014-01-01

    Full Text Available A growing concern for public transit is its inability to shift passenger’s mode from private to public transport. In order to overcome this problem, a more developed feeder bus network and matched schedules will play important roles. The present paper aims to review some of the studies performed on Feeder Bus Network Design and Scheduling Problem (FNDSP based on three distinctive parts of the FNDSP setup, namely, problem description, problem characteristics, and solution approaches. The problems consist of different subproblems including data preparation, feeder bus network design, route generation, and feeder bus scheduling. Subsequently, descriptive analysis and classification of previous works are presented to highlight the main characteristics and solution methods. Finally, some of the issues and trends for future research are identified. This paper is targeted at dealing with the FNDSP to exhibit strategic and tactical goals and also contributes to the unification of the field which might be a useful complement to the few existing reviews.

  16. Analysis of feeder bus network design and scheduling problems.

    Science.gov (United States)

    Almasi, Mohammad Hadi; Mirzapour Mounes, Sina; Koting, Suhana; Karim, Mohamed Rehan

    2014-01-01

    A growing concern for public transit is its inability to shift passenger's mode from private to public transport. In order to overcome this problem, a more developed feeder bus network and matched schedules will play important roles. The present paper aims to review some of the studies performed on Feeder Bus Network Design and Scheduling Problem (FNDSP) based on three distinctive parts of the FNDSP setup, namely, problem description, problem characteristics, and solution approaches. The problems consist of different subproblems including data preparation, feeder bus network design, route generation, and feeder bus scheduling. Subsequently, descriptive analysis and classification of previous works are presented to highlight the main characteristics and solution methods. Finally, some of the issues and trends for future research are identified. This paper is targeted at dealing with the FNDSP to exhibit strategic and tactical goals and also contributes to the unification of the field which might be a useful complement to the few existing reviews.

  17. Integrated network design and scheduling problems :

    Energy Technology Data Exchange (ETDEWEB)

    Nurre, Sarah G.; Carlson, Jeffrey J.

    2014-01-01

    We consider the class of integrated network design and scheduling problems. These problems focus on selecting and scheduling operations that will change the characteristics of a network, while being speci cally concerned with the performance of the network over time. Motivating applications of INDS problems include infrastructure restoration after extreme events and building humanitarian distribution supply chains. While similar models have been proposed, no one has performed an extensive review of INDS problems from their complexity, network and scheduling characteristics, information, and solution methods. We examine INDS problems under a parallel identical machine scheduling environment where the performance of the network is evaluated by solving classic network optimization problems. We classify that all considered INDS problems as NP-Hard and propose a novel heuristic dispatching rule algorithm that selects and schedules sets of arcs based on their interactions in the network. We present computational analysis based on realistic data sets representing the infrastructures of coastal New Hanover County, North Carolina, lower Manhattan, New York, and a realistic arti cial community CLARC County. These tests demonstrate the importance of a dispatching rule to arrive at near-optimal solutions during real-time decision making activities. We extend INDS problems to incorporate release dates which represent the earliest an operation can be performed and exible release dates through the introduction of specialized machine(s) that can perform work to move the release date earlier in time. An online optimization setting is explored where the release date of a component is not known.

  18. Design Students and Companies - What's the Problem?

    DEFF Research Database (Denmark)

    Eriksen, Kaare

    2009-01-01

    How are collaborative projects between university design programs and external partners like companies or institutions integrated in the curriculum and what are the advantages and problems related to such initiatives? Many experiments are done in the area, but until now a more general overview ha...

  19. Wireless device connection problems and design solutions

    Science.gov (United States)

    Song, Ji-Won; Norman, Donald; Nam, Tek-Jin; Qin, Shengfeng

    2016-09-01

    Users, especially the non-expert users, commonly experience problems when connecting multiple devices with interoperability. While studies on multiple device connections are mostly concentrated on spontaneous device association techniques with a focus on security aspects, the research on user interaction for device connection is still limited. More research into understanding people is needed for designers to devise usable techniques. This research applies the Research-through-Design method and studies the non-expert users' interactions in establishing wireless connections between devices. The "Learning from Examples" concept is adopted to develop a study focus line by learning from the expert users' interaction with devices. This focus line is then used for guiding researchers to explore the non-expert users' difficulties at each stage of the focus line. Finally, the Research-through-Design approach is used to understand the users' difficulties, gain insights to design problems and suggest usable solutions. When connecting a device, the user is required to manage not only the device's functionality but also the interaction between devices. Based on learning from failures, an important insight is found that the existing design approach to improve single-device interaction issues, such as improvements to graphical user interfaces or computer guidance, cannot help users to handle problems between multiple devices. This study finally proposes a desirable user-device interaction in which images of two devices function together with a system image to provide the user with feedback on the status of the connection, which allows them to infer any required actions.

  20. Contract Design: The problem of information asymmetry.

    Science.gov (United States)

    Mühlbacher, Axel C; Amelung, Volker E; Juhnke, Christin

    2018-01-12

    Integrated care systems are advocated as an effective method of improving the performance of healthcare systems. These systems outline a payment and care delivery model that intends to tie provider reimbursements to predefined quality metrics. Little is known about the contractual design and the main challenges of delegating "accountability" to these new kinds of organisations and/or contracts. The research question in this article focuses on how healthcare contracts can look like and which possible problems arise in designing such contracts. In this a special interest is placed on information asymmetries. A comprehensive literature review on methods of designing contracts in Integrated Care was conducted. This article is the first in a row of three that all contribute to a specific issue in designing healthcare contracts. Starting with the organisation of contracts and information asymmetries, part 2 focusses on financial options and risks and part 3 finally concludes with the question of risk management and evaluation. Healthcare contracting between providers and payers will have a major impact on the overall design of future healthcare systems. If Integrated care systems or any other similar concept of care delivery are to be contracted directly by payers to manage the continuum of care the costs of market utilisation play an essential role. Transaction costs also arise in the course of the negotiation and implementation of contracts. These costs are the reason why it is generally not possible to conclude perfect (complete) contracts. Problems with asymmetric distribution of information can relate to the situation before a contract is concluded (adverse selection) and after conclusion of a contract (moral hazard). Information asymmetries are seen as a major obstacle to the efficient operation of integrated care programmes. Coordination and motivation problems cannot be solved at no-costs. The presented problems in the design of selective individual contracts

  1. Can Architecture Design Solve Social Problem?

    Science.gov (United States)

    Ginting, S. W.; TSB Darjosanjoto, E.; Sulistyarso, H.

    2017-03-01

    Most of architects and urban designers believe physical design gives impact on our social life. For example, a sign or landmark in the middle of a city makes people find orientation easier. In vice verse, most of social scientists believe it is social dynamic that plays role in shaping our space. How people spend their time moving from real space into cyber space is a proof that life style and IT give impact to space usage. This paper argues that interaction between physical design and social change is a two ways process. Both design aspect and social dynamic influence each other. This paper aims to examine how designing of gated community plays important role in increasing or decreasing segregation, both spatially and socially. The paper explores some architectural design principles applied in a gated community called CitraLand in west Surabaya, Indonesia, and addresses segregation between CitraLanders and outside kampung. We find CitraLand is designed openly and fully accessible for outsiders. It provides public spaces and several accessible gates and streets without walls and fences making all places inside and outside CitraLand spatially integrated. What’s interesting is it still reinforces social segregation due to its policy on prohibiting using the public park. We believe CitraLand’s planning and designing has successfully solved segregation problem spatially not socially.

  2. Contract Design: The problem of information asymmetry

    Directory of Open Access Journals (Sweden)

    Axel C. Mühlbacher

    2018-01-01

    Full Text Available Introduction: Integrated care systems are advocated as an effective method of improving the performance of healthcare systems. These systems outline a payment and care delivery model that intends to tie provider reimbursements to predefined quality metrics. Little is known about the contractual design and the main challenges of delegating “accountability” to these new kinds of organisations and/or contracts. The research question in this article focuses on how healthcare contracts can look like and which possible problems arise in designing such contracts. In this a special interest is placed on information asymmetries.  Methods: A comprehensive literature review on methods of designing contracts in Integrated Care was conducted. This article is the first in a row of three that all contribute to a specific issue in designing healthcare contracts. Starting with the organisation of contracts and information asymmetries, part 2 focusses on financial options and risks and part 3 finally concludes with the question of risk management and evaluation.  Results: Healthcare contracting between providers and payers will have a major impact on the overall design of future healthcare systems. If Integrated care systems or any other similar concept of care delivery are to be contracted directly by payers to manage the continuum of care the costs of market utilisation play an essential role. Transaction costs also arise in the course of the negotiation and implementation of contracts. These costs are the reason why it is generally not possible to conclude perfect (complete contracts. Problems with asymmetric distribution of information can relate to the situation before a contract is concluded (adverse selection and after conclusion of a contract (moral hazard.  Discussion and Conclusions: Information asymmetries are seen as a major obstacle to the efficient operation of integrated care programmes. Coordination and motivation problems cannot be solved

  3. Particle Swarm Optimization for Structural Design Problems

    Directory of Open Access Journals (Sweden)

    Hamit SARUHAN

    2010-02-01

    Full Text Available The aim of this paper is to employ the Particle Swarm Optimization (PSO technique to a mechanical engineering design problem which is minimizing the volume of a cantilevered beam subject to bending strength constraints. Mechanical engineering design problems are complex activities which are computing capability are more and more required. The most of these problems are solved by conventional mathematical programming techniques that require gradient information. These techniques have several drawbacks from which the main one is becoming trapped in local optima. As an alternative to gradient-based techniques, the PSO does not require the evaluation of gradients of the objective function. The PSO algorithm employs the generation of guided random positions when they search for the global optimum point. The PSO which is a nature inspired heuristics search technique imitates the social behavior of bird flocking. The results obtained by the PSO are compared with Mathematical Programming (MP. It is demonstrated that the PSO performed and obtained better convergence reliability on the global optimum point than the MP. Using the MP, the volume of 2961000 mm3 was obtained while the beam volume of 2945345 mm3 was obtained by the PSO.

  4. The Generalized Fixed-Charge Network Design Problem

    DEFF Research Database (Denmark)

    Thomadsen, Tommy; Stidsen, Thomas K.

    2007-01-01

    In this paper we present the generalized fixed-charge network design (GFCND) problem. The GFCND problem is an instance of the so-called generalized network design problems. In such problems, clusters instead of nodes have to be interconnected by a network. The network interconnecting the clusters...... is a fixed-charge network, and thus the GFCND problem generalizes the fixed-charge network design problem. The GFCND problem is related to the more general problem of designing hierarchical telecommunication networks. A mixed integer programming model is described and a branch-cut-and-price algorithm...

  5. Theoretical design and discovery of the most-promising, previously overlooked hybrid perovskite compounds

    Energy Technology Data Exchange (ETDEWEB)

    Zunger, Alex [University of Colorado Boulder; Kazmerski, Lawrence [University of Colorado Boulder; Dalpian, Gustavo [University of Colorado Boulder

    2018-03-14

    The material class of hybrid organic-inorganic perovskites (AMX3) has risen rapidly from a virtually unknown material in photovoltaic applications a short 8-years ago into 20-23% efficient thin-film solar cell devices. As promising as this class of materials is, however, there are limitations associated with its poor long-term stability, non-optimal band gap, and the presence of toxic Pb atom on the metalloid site. An Edisonian laboratory exploration (i.e., growth + characterization) via trial-and-error processes of all other candidate materials, is unpractical. Our approach uses high speed computational design and discovery to screen the ‘best of class” candidates based upon optimal functionalities.

  6. Engineering Encounters: Identifying an Engineering Design Problem

    Science.gov (United States)

    Chizek, Lisa; VanMeeteren, Beth; McDermott, Mark; Uhlenberg, Jill

    2018-01-01

    Engineering is an intriguing way for students to connect the design process with their knowledge of science (NRC 2012). This article describes the "Engineering a Pancake Recipe" design process which was created to make the structure and properties of matter more meaningful for fifth grade students. The whole pancake recipe engineering…

  7. A concept for global optimization of topology design problems

    DEFF Research Database (Denmark)

    Stolpe, Mathias; Achtziger, Wolfgang; Kawamoto, Atsushi

    2006-01-01

    We present a concept for solving topology design problems to proven global optimality. We propose that the problems are modeled using the approach of simultaneous analysis and design with discrete design variables and solved with convergent branch and bound type methods. This concept is illustrated...

  8. An analysis of shift class design problems

    NARCIS (Netherlands)

    L.G. Kroon (Leo); A.W.J. Kolen

    1994-01-01

    textabstractIn this paper we consider a generalization of the Fixed Job Schedule Problem (FJSP) which appears in the aircraft maintenance process at an airport. A number of jobs must be carried out where each job requires processing from a fixed time to a fixed finish time. These jobs must be

  9. WITHDRAWAL OF PREVIOUS COMPLAINT. A COMPARISON OF THE OLD AND THE NEW CRIMINAL CODE. PROBLEMS OF COMPARATIVE LAW

    Directory of Open Access Journals (Sweden)

    Alin Sorin NICOLESCU

    2015-07-01

    Full Text Available In criminal law previous complaint has a double legal valence, material and procedural in nature, constituting a condition for criminal liability, but also a functional condition in cases expressly and limitatively provided by law, a consequence of criminal sanction condition. For certain offenses criminal law determines the initiation of the criminal complaint by the introduction of previous complaint by the injured party, without its absence being a question of removing criminal liability. From the perspective of criminal material law conditioning of the existence of previous complaint ,its lack and withdrawal, are regulated by art. 157 and 158 of the New Penal Code, with significant changes in relation to the old regulation of the institution . In terms of procedural aspect , previous complaint is regulated in art. 295-298 of the New Code of Criminal Procedure. Regarding the withdrawal of the previuos complaint, in the case of offenses for which the initiation of criminal proceedings is subject to the existence of such a complaint, we note that in the current Criminal Code this legal institution is regulated separately, representing both a cause for removal of criminal liability and a cause that preclude criminal action. This unilateral act of the will of the injured party - the withdrawal of the previous complaint, may be exercised only under certain conditions, namely: it can only be promoted in the case of the offenses for which the initiation of criminal proceedings is subject to the introduction of a previous complaint; it is made exclusively by the rightholder, by legal representatives or with the consent of the persons required by law for persons lacking legal capacity or having limited legal capacity;it must intervene until giving final judgment and it must represent an express and explicit manifestation. A novelty isrepresented by the possibility of withdrawing previous complaint if the prosecution was driven ex officio, although for

  10. Multiobjective engineering design optimization problems: a sensitivity analysis approach

    Directory of Open Access Journals (Sweden)

    Oscar Brito Augusto

    2012-12-01

    Full Text Available This paper proposes two new approaches for the sensitivity analysis of multiobjective design optimization problems whose performance functions are highly susceptible to small variations in the design variables and/or design environment parameters. In both methods, the less sensitive design alternatives are preferred over others during the multiobjective optimization process. While taking the first approach, the designer chooses the design variable and/or parameter that causes uncertainties. The designer then associates a robustness index with each design alternative and adds each index as an objective function in the optimization problem. For the second approach, the designer must know, a priori, the interval of variation in the design variables or in the design environment parameters, because the designer will be accepting the interval of variation in the objective functions. The second method does not require any law of probability distribution of uncontrollable variations. Finally, the authors give two illustrative examples to highlight the contributions of the paper.

  11. Tails from previous exposures: a general problem in setting reference levels for the assessment of internal contamination

    International Nuclear Information System (INIS)

    Breuer, F.; Frittelli, L.

    1988-01-01

    Reference levels for retention and excretion are evaluated for routine and special monitoring following the intake of a fraction of ICRP annual limits (ALIs) or of a unit activity. Methodologies are also suggested for taking into account the contribution by previous intakes to excretion or retention

  12. Scaffold Seeking: A Reverse Design of Scaffolding in Computer-Supported Word Problem Solving

    Science.gov (United States)

    Cheng, Hercy N. H.; Yang, Euphony F. Y.; Liao, Calvin C. Y.; Chang, Ben; Huang, Yana C. Y.; Chan, Tak-Wai

    2015-01-01

    Although well-designed scaffolding may assist students to accomplish learning tasks, its insufficient capability to dynamically assess students' abilities and to adaptively support them may result in the problem of overscaffolding. Our previous project has also shown that students using scaffolds to solve mathematical word problems for a long time…

  13. Radiation streaming: the continuing problem of shield design

    International Nuclear Information System (INIS)

    Avery, A.F.

    1977-01-01

    The practical problems of shield design are reviewed and the major difficulties are shown to be those associated with streaming problems. The situations in which streaming occurs in various types of reactor are described including LMFBR's and fusion devices, and examples are given of ways in which the problems have been solved

  14. The Design Process for "PLATO[R] Math Problem Solving."

    Science.gov (United States)

    Mulcahy, Robert

    2001-01-01

    PLATO Learning, Inc., a developer of computer-based instruction, recently released "Math Problem Solving." This product was designed to teach strategies for solving math problems, and consists of 19 problem-solving activities, ranging from basic math to algebra. Each activity includes tools to help find a solution and rule-based coaching to…

  15. The Steiner Multigraph Problem: Wildlife corridor design for multiple species

    Science.gov (United States)

    Katherine J. Lai; Carla P. Gomes; Michael K. Schwartz; Kevin S. McKelvey; David E. Calkin; Claire A. Montgomery

    2011-01-01

    The conservation of wildlife corridors between existing habitat preserves is important for combating the effects of habitat loss and fragmentation facing species of concern. We introduce the Steiner Multigraph Problem to model the problem of minimum-cost wildlife corridor design for multiple species with different landscape requirements. This problem can also model...

  16. Modeling the Structure and Complexity of Engineering Routine Design Problems

    NARCIS (Netherlands)

    Jauregui Becker, Juan Manuel; Wits, Wessel Willems; van Houten, Frederikus J.A.M.

    2011-01-01

    This paper proposes a model to structure routine design problems as well as a model of its design complexity. The idea is that having a proper model of the structure of such problems enables understanding its complexity, and likewise, a proper understanding of its complexity enables the development

  17. A matheuristic for the liner shipping network design problem

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Desaulniers, Guy

    2012-01-01

    for revenue and transshipment of cargo along with in/decrease of vessel- and operational cost for the current solution. The evaluation functions may be used by heuristics in general to evaluate changes to a network design without solving a large scale multicommodity flow problem.......We present a matheuristic, an integer programming based heuristic, for the Liner Shipping Network Design Problem. The heuristic applies a greedy construction heuristic based on an interpretation of the liner shipping network design problem as a multiple quadratic knapsack problem. The construction...

  18. On the computational complexity of sequence design problems

    Energy Technology Data Exchange (ETDEWEB)

    Hart, W.E. [Sandia National Labs., Albuquerque, NM (United States). Algorithms and Discrete Mathematics Dept.

    1996-12-31

    Inverse protein folding concerns the identification of an amino acid sequence that folds to a given structure. Sequence design problems attempt to avoid the apparent difficulty of inverse protein folding by defining an energy that can be minimized to find protein-like sequences. The authors evaluate the practical relevance of two sequence design problems by analyzing their computation complexity. They show that the canonical method of sequence design is intractable, and describe approximation algorithms for this problem. The authors also describe an efficient algorithm that exactly solves the grand canonical method. The analysis shows how sequence design problems can fail to reduce the difficulty of the inverse protein folding problem, and highlights the need to analyze these problems to evaluate their practical relevance.

  19. Solving network design problems via decomposition, aggregation and approximation

    CERN Document Server

    Bärmann, Andreas

    2016-01-01

    Andreas Bärmann develops novel approaches for the solution of network design problems as they arise in various contexts of applied optimization. At the example of an optimal expansion of the German railway network until 2030, the author derives a tailor-made decomposition technique for multi-period network design problems. Next, he develops a general framework for the solution of network design problems via aggregation of the underlying graph structure. This approach is shown to save much computation time as compared to standard techniques. Finally, the author devises a modelling framework for the approximation of the robust counterpart under ellipsoidal uncertainty, an often-studied case in the literature. Each of these three approaches opens up a fascinating branch of research which promises a better theoretical understanding of the problem and an increasing range of solvable application settings at the same time. Contents Decomposition for Multi-Period Network Design Solving Network Design Problems via Ag...

  20. Vacuum problems of thermonuclear reactor design

    International Nuclear Information System (INIS)

    Paty, L.

    1981-01-01

    A thermonuclear reactor can be considered to be a vacuum system in which constant concentration should be maintained of reacting particles while permanently discharging the undesirable particles using a system of pumps. The discharging proceeds in two stages: in the former, the reactor is degassed using external pumps connected to the reactor chamber through a pumping pipe. The latter in which hydrogen is admitted, uses high pump-rate machines based on the principle of the binding of the gas to the pump surface and must not introduce molecules of higher atomic mass in the system. Turbomolecular pumps of diffusion oil pumps are most suitable for the former stage while condensation, cryosorption, titanium pumping machines and special pumping methods are most suitable for the latter stage. Examples are shown of the pump system design for Tokamak 10 and for facilities at the Euratom laboratory in Fontenay-aux-Roses. (M.D.)

  1. Embracing Wicked Problems: The Turn to Design in Composition Studies

    Science.gov (United States)

    Marback, Richard

    2009-01-01

    Recent appeal to the concept of design in composition studies benefits teaching writing in digital media. Yet the concept of design has not been developed enough to fully benefit composition instruction. This article develops an understanding of design as a matter of resolving wicked problems and makes a case for the advantages of this…

  2. Artificial intelligence and design: Opportunities, research problems and directions

    Science.gov (United States)

    Amarel, Saul

    1990-01-01

    The issues of industrial productivity and economic competitiveness are of major significance in the U.S. at present. By advancing the science of design, and by creating a broad computer-based methodology for automating the design of artifacts and of industrial processes, we can attain dramatic improvements in productivity. It is our thesis that developments in computer science, especially in Artificial Intelligence (AI) and in related areas of advanced computing, provide us with a unique opportunity to push beyond the present level of computer aided automation technology and to attain substantial advances in the understanding and mechanization of design processes. To attain these goals, we need to build on top of the present state of AI, and to accelerate research and development in areas that are especially relevant to design problems of realistic complexity. We propose an approach to the special challenges in this area, which combines 'core work' in AI with the development of systems for handling significant design tasks. We discuss the general nature of design problems, the scientific issues involved in studying them with the help of AI approaches, and the methodological/technical issues that one must face in developing AI systems for handling advanced design tasks. Looking at basic work in AI from the perspective of design automation, we identify a number of research problems that need special attention. These include finding solution methods for handling multiple interacting goals, formation problems, problem decompositions, and redesign problems; choosing representations for design problems with emphasis on the concept of a design record; and developing approaches for the acquisition and structuring of domain knowledge with emphasis on finding useful approximations to domain theories. Progress in handling these research problems will have major impact both on our understanding of design processes and their automation, and also on several fundamental questions

  3. Design as co-evolution of problem, solution, and audience

    DEFF Research Database (Denmark)

    Halstrøm, Per Liljenberg; Galle, Per

    2014-01-01

    design beyond the level of definitions, reviewing canonical theories about design as a professional enterprise. We find that the well-established theoretical notion of ‘co-evolution’ of problem and solution in design has its merits in regard to understanding design deliberations; but also that existing......The meaning of ‘design’ can be captured in a general way by a good definition, but even the best definition cannot provide an understanding sufficiently deep to guide the professional designer or the student of design in the intricate deliberations of doing design in practice. Therefore we explore...

  4. Expert vs. novice: Problem decomposition/recomposition in engineering design

    Science.gov (United States)

    Song, Ting

    The purpose of this research was to investigate the differences of using problem decomposition and problem recomposition among dyads of engineering experts, dyads of engineering seniors, and dyads of engineering freshmen. Fifty participants took part in this study. Ten were engineering design experts, 20 were engineering seniors, and 20 were engineering freshmen. Participants worked in dyads to complete an engineering design challenge within an hour. The entire design process was video and audio recorded. After the design session, members participated in a group interview. This study used protocol analysis as the methodology. Video and audio data were transcribed, segmented, and coded. Two coding systems including the FBS ontology and "levels of the problem" were used in this study. A series of statistical techniques were used to analyze data. Interview data and participants' design sketches also worked as supplemental data to help answer the research questions. By analyzing the quantitative and qualitative data, it was found that students used less problem decomposition and problem recomposition than engineer experts in engineering design. This result implies that engineering education should place more importance on teaching problem decomposition and problem recomposition. Students were found to spend less cognitive effort when considering the problem as a whole and interactions between subsystems than engineer experts. In addition, students were also found to spend more cognitive effort when considering details of subsystems. These results showed that students tended to use dept-first decomposition and experts tended to use breadth-first decomposition in engineering design. The use of Function (F), Behavior (B), and Structure (S) among engineering experts, engineering seniors, and engineering freshmen was compared on three levels. Level 1 represents designers consider the problem as an integral whole, Level 2 represents designers consider interactions between

  5. Instructional Design-Based Research on Problem Solving Strategies

    Science.gov (United States)

    Emre-Akdogan, Elçin; Argün, Ziya

    2016-01-01

    The main goal of this study is to find out the effect of the instructional design method on the enhancement of problem solving abilities of students. Teaching sessions were applied to ten students who are in 11th grade, to teach them problem solving strategies which are working backwards, finding pattern, adopting a different point of view,…

  6. A matheuristic for the liner shipping network design problem

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Desaulniers, Guy; Pisinger, David

    2014-01-01

    We present an integer programming based heuristic, a matheuristic, for the liner shipping network design problem. This problem consists of finding a set of container shipping routes defining a capacitated network for cargo transport. The objective is to maximize the revenue of cargo transport...

  7. Adaptive Pareto Set Estimation for Stochastic Mixed Variable Design Problems

    Science.gov (United States)

    2009-03-01

    ix I. Introduction ...1 ADAPTIVE PARETO SET ESTIMATION FOR STOCHASTIC MIXED VARIABLE DESIGN PROBLEMS I. Introduction 1.1. Problem Setting A scalar-valued function...Tenfelde-Podehl, D. (2003). Computation of Ideal and Nadir values and Implications for Their Use in MCDM methods. European Journal of Operational

  8. Applicability Problem in Optimum Reinforced Concrete Structures Design

    Directory of Open Access Journals (Sweden)

    Ashara Assedeq

    2016-01-01

    Full Text Available Optimum reinforced concrete structures design is very complex problem, not only considering exactness of calculus but also because of questionable applicability of existing methods in practice. This paper presents the main theoretical mathematical and physical features of the problem formulation as well as the review and analysis of existing methods and solutions considering their exactness and applicability.

  9. Exploring the Learning Problems and Resource Usage of Undergraduate Industrial Design Students in Design Studio Courses

    Science.gov (United States)

    Chen, Wenzhi

    2016-01-01

    Design is a powerful weapon for modern companies so it is important to have excellent designers in the industry. The purpose of this study is to explore the learning problems and the resources that students use to overcome problems in undergraduate industrial design studio courses. A survey with open-type questions was conducted to collect data.…

  10. Cultivating Peace through Design Thinking: Problem Solving with PAST Foundation

    Science.gov (United States)

    Deaner, Kat; McCreery-Kellert, Heather

    2018-01-01

    Design thinking is a methodology that emphasizes reasoning and decision-making as part of the problem-solving process. It is a structured framework for identifying challenges, gathering information, generating potential solutions, refining ideas, and testing solutions. Design thinking offers valuable skills that will serve students well as they…

  11. A Multilevel Analysis of Problem-Based Learning Design Characteristics

    Science.gov (United States)

    Scott, Kimberly S.

    2014-01-01

    The increasing use of experience-centered approaches like problem-based learning (PBL) by learning and development practitioners and management educators has raised interest in how to design, implement and evaluate PBL in that field. Of particular interest is how to evaluate the relative impact of design characteristics that exist at the…

  12. LEARNING STYLES AND STUDENTS’ PERFORMANCE IN DESIGN PROBLEM SOLVING

    Directory of Open Access Journals (Sweden)

    Elçin Tezel

    2010-07-01

    Full Text Available Design curricula and all core design studio courses are prepared for performance attainment by giving theoretical and professional training. However students’ performance may be affected by both the constraints set on a design problem, and their learning styles. This study explores the performance of interior architectural students in relation to their learning styles (as proposed by Kolb’s Experiential Learning Theory, and different types of constraints set on design problems. Design performance, measured as conceptual development, form and spatial configuration, structural innovation and ergonomics, and craftsmanship, was found to change throughout the two bipolar continuum of the learning cycle with regard to two design conditions characterized by different types of constraint use.

  13. An Algorithm for the Mixed Transportation Network Design Problem.

    Science.gov (United States)

    Liu, Xinyu; Chen, Qun

    2016-01-01

    This paper proposes an optimization algorithm, the dimension-down iterative algorithm (DDIA), for solving a mixed transportation network design problem (MNDP), which is generally expressed as a mathematical programming with equilibrium constraint (MPEC). The upper level of the MNDP aims to optimize the network performance via both the expansion of the existing links and the addition of new candidate links, whereas the lower level is a traditional Wardrop user equilibrium (UE) problem. The idea of the proposed solution algorithm (DDIA) is to reduce the dimensions of the problem. A group of variables (discrete/continuous) is fixed to optimize another group of variables (continuous/discrete) alternately; then, the problem is transformed into solving a series of CNDPs (continuous network design problems) and DNDPs (discrete network design problems) repeatedly until the problem converges to the optimal solution. The advantage of the proposed algorithm is that its solution process is very simple and easy to apply. Numerical examples show that for the MNDP without budget constraint, the optimal solution can be found within a few iterations with DDIA. For the MNDP with budget constraint, however, the result depends on the selection of initial values, which leads to different optimal solutions (i.e., different local optimal solutions). Some thoughts are given on how to derive meaningful initial values, such as by considering the budgets of new and reconstruction projects separately.

  14. Collaborative Problem-solution Co-evolution in Creative Design

    DEFF Research Database (Denmark)

    Wiltschnig, Stefan; Christensen, Bo; J. Ball, Linden

    2013-01-01

    . The analysis revealed that co-evolution episodes occurred regularly and embodied various directional transitions between problem and solution spaces. Moreover, the team leader often initiated this co-evolution. Co-evolution episodes linked with other creative activities such as analogising and mental......Creative design concepts are often viewed as developing iteratively, with the design problem and solutions ‘co-evolving’ in a mutually adaptive manner. We report a study examining whether the co-evolution concept captures the creativity arising in collaborative, team-based design practice...... simulation and there was a clear association between co-evolution and expressions of epistemic uncertainty, suggesting that designers were dealing with considerable complexity and ambiguity. Our findings support the view that co-evolution is the ‘engine’ of creativity in collaborative design....

  15. IODC 2014 Illumination design problem: the Cinderella Lamp

    Science.gov (United States)

    Cassarly, William J.

    2014-12-01

    For the 3rd time, the International Optical Design Conference (IODC) included an Illumination Design contest. This year, the contest involved designing the illuminator to project the 1950 Walt Disney "Cinderella" movie using a box of optical knick-knacks. The goal of the problem was to provide the highest screen lumens with greater than 30% uniformity. There were 12 entries from 3 different countries. Three different commercial optical/illumination design packages were used. The winning solution, provided by Alois Herkommer, provided 371 screen lumens.

  16. University of Texas Safeguards by Design Problem Statement

    Energy Technology Data Exchange (ETDEWEB)

    Rauch, Eric Benton [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Scherer, Carolynn P. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ruggiero, Christy E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2018-01-22

    This document describes the problem statement that students at the University of Texas will use for their senior level capstone design class. The purpose of this project is to introduce students to Safeguards by Design concepts as part of their capstone design course at the culmination of their degree program. This work is supported by Los Alamos National Laboratory with FY17 and FY18 programmatic funding from the U. S. Department of Energy’s (DOE) National Nuclear Security Administration (NNSA), through the Office of Defense Nuclear Nonproliferation (DNN), Office of International Nuclear Safeguards (INS), Next Generation Safeguards Initiative (NGSI), Human Resource Development Program, Safeguards by Design Project.

  17. Problem statement for optimal design of steel structures

    Directory of Open Access Journals (Sweden)

    Ginzburg Aleksandr Vital'evich

    2014-07-01

    Full Text Available The presented article considers the following complex of tasks. The main stages of the life cycle of a building construction with the indication of process entrance and process exit are described. Requirements imposed on steel constructions are considered. The optimum range of application for steel designs is specified, as well as merits and demerits of a design material. The nomenclature of metal designs is listed - the block diagram is constructed. Possible optimality criteria of steel designs, offered by various authors for various types of constructions are considered. It is established that most often the criterion of a minimum of design mass is accepted as criterion of optimality; more rarely - a minimum of the given expenses, a minimum of a design cost in business. In the present article special attention is paid to a type of objective function of optimization problem. It is also established that depending on the accepted optimality criterion, the use of different types of functions is possible. This complexity of objective function depends on completeness of optimality criterion application. In the work the authors consider the following objective functions: the mass of the main element of a design; objective function by criterion of factory cost; objective function by criterion of cost in business. According to these examples it can be seen that objective functions by the criteria of labor expenses for production of designs are generally non-linear, which complicates solving the optimization problem. Another important factor influencing the problem of optimal design solution for steel designs, which is analyzed, is account for operating restrictions. In the article 8 groups of restrictions are analyzed. Attempts to completely account for the parameters of objective function optimized by particular optimality criteria, taking into account all the operating restrictions, considerably complicates the problem of designing. For solving this

  18. Problems in the design and development of 750 MW turbogenerators

    CERN Document Server

    Anempodistov, V P; Urusov, I D; Fry, D W; Higinbotham, W

    1963-01-01

    Problems in the Design and Development of 750 MW Turbo-Generators covers selected problems mainly related to projected machines in the development of turbo-generators. This book describes the main lines of research at the Electromechanics Institute of the U.S.S.R. Academy of Sciences.This book is divided into six chapters and begins with an overview of the progress in the generation of electricity along with the rapid economic development of the U.S.S.R. The succeeding chapter deals with the use of efficient cooling system of the winding copper to address the problem of electrical machine's un

  19. Integrated Design Process in Problem-Based Learning

    DEFF Research Database (Denmark)

    Knudstrup, Mary-Ann

    2004-01-01

    This article reports and reflects on the learning achievements and the educational experiences in connection with the first years of the curriculum in Architecture at Aalborg University ?s Civil Engineer Education in Architecture & Design. In the article I will focus on the learning activity...... and the method that are developed during the semester when working with an Integrated Design Process combining architecture, design, functional aspects, energy consumption, indoor environment, technology, and construction. I will emphasize the importance of working with different tools in the design process, e.......g. the computer as a tool for designing and optimising the building. I will also consider the dilemma of the Integrated Design Process in Problem Based Learning that emerges when the number of courses in the learning model, as is often the case, clashes with the demand for time and scope for reflection which...

  20. Designing Digital Problem Based Learning Tasks that Motivate Students

    Science.gov (United States)

    van Loon, Anne-Marieke; Ros, Anje; Martens, Rob

    2013-01-01

    This study examines whether teachers are able to apply the principles of autonomy support and structure support in designing digital problem based learning (PBL) tasks. We examine whether these tasks are more autonomy- and structure-supportive and whether primary and secondary school students experience greater autonomy, competence, and motivation…

  1. Coleman's problem with institutional design : neglect of social rationality

    NARCIS (Netherlands)

    Lindenberg, S

    2003-01-01

    This paper tries to answer the question how it is possible that such a giant of sociology as James Coleman produced so little of what he considered the most important work for sociologists : good institutional design. I argue that the answer lies in the fact that the most serious problem for which

  2. An Overview of Catalog Design Problems in Resource Discovery.

    Science.gov (United States)

    Goodchild, Andrew

    1996-01-01

    Many catalogs are built in an ad hoc fashion, which results in uncertain quality in publicly accessible network catalogs. This article discusses problems facing designers building catalogs for large networks, relating them to resource discovery; provides a usability framework based on library science and human computer interaction literature; and…

  3. LMI–based robust controller design approach in aircraft multidisciplinary design optimization problem

    Directory of Open Access Journals (Sweden)

    Qinghua Zeng

    2015-07-01

    Full Text Available This article proposes a linear matrix inequality–based robust controller design approach to implement the synchronous design of aircraft control discipline and other disciplines, in which the variation in design parameters is treated as equivalent perturbations. Considering the complicated mapping relationships between the coefficient arrays of aircraft motion model and the aircraft design parameters, the robust controller designed is directly based on the variation in these coefficient arrays so conservative that the multidisciplinary design optimization problem would be too difficult to solve, or even if there is a solution, the robustness of design result is generally poor. Therefore, this article derives the uncertainty model of disciplinary design parameters based on response surface approximation, converts the design problem of the robust controller into a problem of solving a standard linear matrix inequality, and theoretically gives a less conservative design method of the robust controller which is based on the variation in design parameters. Furthermore, the concurrent subspace approach is applied to the multidisciplinary system with this kind of robust controller in the design loop. A multidisciplinary design optimization of a tailless aircraft as example is shown that control discipline can be synchronous optimal design with other discipline, especially this method will greatly reduce the calculated amount of multidisciplinary design optimization and make multidisciplinary design optimization results more robustness of flight performance.

  4. Biosocial models of adolescent problem behavior: extension to panel design.

    Science.gov (United States)

    Drigotas, S M; Udry, J R

    1993-01-01

    We extended the biosocial model of problem behavior tested by Udry (1990) to a panel design, following a sample of over one hundred boys in adolescence for three years. We found the expected results for sociological variables, but weaker effects for testosterone than Udry found on cross-sectional data. Using panel models with lagged hormone effects, we identified relationships between Time-1 testosterone and problem behavior one year or more later. The relationship between testosterone and problem behavior was not present for subsequent measures of testosterone, either in cross-section or with time-lagged models. Therefore we cannot interpret the results as showing testosterone effects on problem behavior. Rather it appears that testosterone level in early adolescence is a marker for a more general growth trajectory of early development.

  5. Creating geometrically robust designs for highly sensitive problems using topology optimization: Acoustic cavity design

    DEFF Research Database (Denmark)

    Christiansen, Rasmus E.; Lazarov, Boyan S.; Jensen, Jakob S.

    2015-01-01

    Resonance and wave-propagation problems are known to be highly sensitive towards parameter variations. This paper discusses topology optimization formulations for creating designs that perform robustly under spatial variations for acoustic cavity problems. For several structural problems, robust...... and limitations are discussed. In addition, a known explicit penalization approach is considered for comparison. For near-uniform spatial variations it is shown that highly robust designs can be obtained using the double filter approach. It is finally demonstrated that taking non-uniform variations into account...... further improves the robustness of the designs....

  6. Topology optimization problems with design-dependent sets of constraints

    DEFF Research Database (Denmark)

    Schou, Marie-Louise Højlund

    for all elements independently of the values of the design variables. The investigations include validating constraint qualifications, attacking the problem formulations directly, and bounding the objective function value. We consider different constraint qualifications and whether they hold for the MPEC...... that a general nonlinear interior-point algorithm applied to the MPEC formulations outperforms a general nonlinear active-set sequential quadratic programming method. Inspired by this, we implement an interior-point algorithm such that we have full control of all aspects of the code. Solving the stress...... constrained structural topology optimization problem is computationally challenging. We therefore present a technique that decides whether it may pay-off to actually treat the stress constrained problem. The technique finds lower and upper bounds on the objective function value of the stress constrained...

  7. An outer approximation method for the road network design problem.

    Science.gov (United States)

    Asadi Bagloee, Saeed; Sarvi, Majid

    2018-01-01

    Best investment in the road infrastructure or the network design is perceived as a fundamental and benchmark problem in transportation. Given a set of candidate road projects with associated costs, finding the best subset with respect to a limited budget is known as a bilevel Discrete Network Design Problem (DNDP) of NP-hard computationally complexity. We engage with the complexity with a hybrid exact-heuristic methodology based on a two-stage relaxation as follows: (i) the bilevel feature is relaxed to a single-level problem by taking the network performance function of the upper level into the user equilibrium traffic assignment problem (UE-TAP) in the lower level as a constraint. It results in a mixed-integer nonlinear programming (MINLP) problem which is then solved using the Outer Approximation (OA) algorithm (ii) we further relax the multi-commodity UE-TAP to a single-commodity MILP problem, that is, the multiple OD pairs are aggregated to a single OD pair. This methodology has two main advantages: (i) the method is proven to be highly efficient to solve the DNDP for a large-sized network of Winnipeg, Canada. The results suggest that within a limited number of iterations (as termination criterion), global optimum solutions are quickly reached in most of the cases; otherwise, good solutions (close to global optimum solutions) are found in early iterations. Comparative analysis of the networks of Gao and Sioux-Falls shows that for such a non-exact method the global optimum solutions are found in fewer iterations than those found in some analytically exact algorithms in the literature. (ii) Integration of the objective function among the constraints provides a commensurate capability to tackle the multi-objective (or multi-criteria) DNDP as well.

  8. IPDO-2007: Inverse Problems, Design and Optimization Symposium

    Science.gov (United States)

    2007-08-01

    NAMES AND ADDRESSES U.S. Army Research Office P.O. Box 12211 Research Triangle Park, NC 27709-2211 15. SUBJECT TERMS Inverse problems; design...Benedito Maciel Nei Brasil Neto Felipe Viana Valder Steffen Jr. 149 Sumeet Parashar Nader Fateh 150 Marcelo Colaço George Dulikravich Debasis...PROGRESS REPORT INSTRUCTIONS. MEMORANDUM OF TRANSMITTAL U.S. Army Research Office ATTN: AMSRL-RO-BI (TR) P.O. Box 12211 Research

  9. Mechanical design problems associated with turbopump fluid film bearings

    Science.gov (United States)

    Evces, Charles R.

    1990-01-01

    Most high speed cryogenic turbopumps for liquid propulsion rocket engines currently use ball or roller contact bearings for rotor support. The operating speeds, loads, clearances, and environments of these pumps combine to make bearing wear a limiting factor on turbopump life. An example is the high pressure oxygen turbopump (HPOTP) used in the Space Shuttle Main Engine (SSME). Although the HPOTP design life is 27,000 seconds at 30,000 rpms, or approximately 50 missions, bearings must currently be replaced after 2 missions. One solution to the bearing wear problem in the HPOTP, as well as in future turbopump designs, is the utilization of fluid film bearings in lieu of continuous contact bearings. Hydrostatic, hydrodynamic, and damping seal bearings are all replacement candidates for contact bearings in rocket engine high speed turbomachinery. These three types of fluid film bearings have different operating characteristics, but they share a common set of mechanical design opportunities and difficulties. Results of research to define some of the mechanical design issues are given. Problems considered include transient strat/stop rub, non-operational rotor support, bearing wear inspection and measurement, and bearing fluid supply route. Emphasis is given to the HPOTP preburner pump (PBP) bearing, but the results are pertinent to high-speed cryogenic turbomachinery in general.

  10. Guaranteed Discrete Energy Optimization on Large Protein Design Problems.

    Science.gov (United States)

    Simoncini, David; Allouche, David; de Givry, Simon; Delmas, Céline; Barbe, Sophie; Schiex, Thomas

    2015-12-08

    In Computational Protein Design (CPD), assuming a rigid backbone and amino-acid rotamer library, the problem of finding a sequence with an optimal conformation is NP-hard. In this paper, using Dunbrack's rotamer library and Talaris2014 decomposable energy function, we use an exact deterministic method combining branch and bound, arc consistency, and tree-decomposition to provenly identify the global minimum energy sequence-conformation on full-redesign problems, defining search spaces of size up to 10(234). This is achieved on a single core of a standard computing server, requiring a maximum of 66GB RAM. A variant of the algorithm is able to exhaustively enumerate all sequence-conformations within an energy threshold of the optimum. These proven optimal solutions are then used to evaluate the frequencies and amplitudes, in energy and sequence, at which an existing CPD-dedicated simulated annealing implementation may miss the optimum on these full redesign problems. The probability of finding an optimum drops close to 0 very quickly. In the worst case, despite 1,000 repeats, the annealing algorithm remained more than 1 Rosetta unit away from the optimum, leading to design sequences that could differ from the optimal sequence by more than 30% of their amino acids.

  11. A matheuristic for the liner shipping network design problem

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Desaulniers, Guy; Pisinger, David

    the available fleet of container vessels. The cargo transports make extensive use of transshipments between routes and the number of transshipments of the cargo flow is decisive for network profitability. Computational results are reported for the benchmark suite LINER-LIB 2012 following the industry standard......We present a matheuristic, an integer programming based heuristic, for the liner shipping network design problem. This problem consists of finding a set of container shipping routes defining a capacitated network for cargo transport. The objective is to maximize the revenue of cargo transport......, while minimizing the cost of operating the network. Liner shipping companies publish a set of routes with a time schedule, and it is an industry standard to have a weekly departure at each port call on a route. A weekly frequency is achieved by deploying several vessels to a single route, respecting...

  12. Silica problem in the design of geothermal power plants

    Energy Technology Data Exchange (ETDEWEB)

    DiPippo, R.

    1985-02-01

    The purpose of this study is to examine the silica problem from the perspective of the power plant designer and to develop a procedure to enable a quick estimate to be made of the potential seriousness of the silica deposition problem for a wide variety of resources and for selected types of power plant. The method employs correlations for the equilibrium solubilities of quartz and amorphous silica and for the saturated liquid enthalpy and the latent heat of water substance. Single- and double-flash plants optimized for highest thermodynamic efficiency are considered. Binary-type plants are included generically without mention of cycle specifics. The results are presented both graphically and in tabular form, and the governing equations will be given in an easily-programmable form.

  13. A Supply Chain Design Problem Integrated Facility Unavailabilities Management

    Directory of Open Access Journals (Sweden)

    Fouad Maliki

    2016-08-01

    Full Text Available A supply chain is a set of facilities connected together in order to provide products to customers. The supply chain is subject to random failures caused by different factors which cause the unavailability of some sites. Given the current economic context, the management of these unavailabilities is becoming a strategic choice to ensure the desired reliability and availability levels of the different supply chain facilities. In this work, we treat two problems related to the field of supply chain, namely the design and unavailabilities management of logistics facilities. Specifically, we consider a stochastic distribution network with consideration of suppliers' selection, distribution centres location (DCs decisions and DCs’ unavailabilities management. Two resolution approaches are proposed. The first approach called non-integrated consists on define the optimal supply chain structure using an optimization approach based on genetic algorithms (GA, then to simulate the supply chain performance with the presence of DCs failures. The second approach called integrated approach is to consider the design of the supply chain problem and unavailabilities management of DCs in the same model. Note that, we replace each unavailable DC by performing a reallocation using GA in the two approaches. The obtained results of the two approaches are detailed and compared showing their effectiveness.

  14. Inflatable Antenna for CubeSat: Extension of the Previously Developed S-Band Design to the X-Band

    Science.gov (United States)

    Babuscia, Alessandra; Choi, Thomas; Cheung, Kar-Ming; Thangavelautham, Jekan; Ravichandran, Mithun; Chandra, Aman

    2015-01-01

    The inflatable antenna for CubeSat is a 1 meter antenna reflector designed with one side reflective Mylar, another side clear Mylar with a patch antenna at the focus. The development of this technology responds to the increasing need for more capable communication systems to allow CubeSats to operate autonomously in interplanetary missions. An initial version of the antenna for the S-Band was developed and tested in both anechoic chamber and vacuum chamber. Recent developments in transceivers and amplifiers for CubeSat at X-band motivated the extension from the S-Band to the X-Band. This paper describes the process of extending the design of the antenna to the X-Band focusing on patch antenna redesign, new manufacturing challenges and initial results of experimental tests.

  15. Crucial problems in the design of a terahertz tripler

    International Nuclear Information System (INIS)

    Meng Jin; Zhang Dehai; Jiang Changhong; Zhao Xin; Yan Dashuai; Huang Jian

    2015-01-01

    A frequency-multiplied source at the terahertz band using discrete planar Schottky diodes, which is a critical element in heterodyne instruments, has been studied by some domestic research institutions in recent years. Besides the design method, there are still many crucial problems that must be taken into consideration in the design. This article mainly discuss three aspects based on the measured data of a 225 GHz tripler that we designed. Firstly, the accuracy of the diode model concerns the reliability of the simulation results. According to the Spice parameters and the measured results, the physical size and the DC parameter of the Schottky diode can be corrected until there is a good consistency between the simulated and measured results. Secondly, the heat accumulation happens to the Schottky junction when the high input power is added. A steady-state thermal simulation is done and the results show that the hottest temperature is about 140 °C with 250 mW input power, which is safe to the diode. Lastly, some non-ideal factors are brought during the assembly process such as the uncertainty in the conductive adhesive shape and location deviation of the circuit. Furthermore, the effect on the performance of the frequency multiplier is calculated in this work. (paper)

  16. Crucial problems in the design of a terahertz tripler

    Science.gov (United States)

    Jin, Meng; Dehai, Zhang; Changhong, Jiang; Xin, Zhao; Jian, Huang; Dashuai, Yan

    2015-08-01

    A frequency-multiplied source at the terahertz band using discrete planar Schottky diodes, which is a critical element in heterodyne instruments, has been studied by some domestic research institutions in recent years. Besides the design method, there are still many crucial problems that must be taken into consideration in the design. This article mainly discuss three aspects based on the measured data of a 225 GHz tripler that we designed. Firstly, the accuracy of the diode model concerns the reliability of the simulation results. According to the Spice parameters and the measured results, the physical size and the DC parameter of the Schottky diode can be corrected until there is a good consistency between the simulated and measured results. Secondly, the heat accumulation happens to the Schottky junction when the high input power is added. A steady-state thermal simulation is done and the results show that the hottest temperature is about 140 °C with 250 mW input power, which is safe to the diode. Lastly, some non-ideal factors are brought during the assembly process such as the uncertainty in the conductive adhesive shape and location deviation of the circuit. Furthermore, the effect on the performance of the frequency multiplier is calculated in this work.

  17. The earthquake problem in engineering design: generating earthquake design basis information

    International Nuclear Information System (INIS)

    Sharma, R.D.

    1987-01-01

    Designing earthquake resistant structures requires certain design inputs specific to the seismotectonic status of the region, in which a critical facility is to be located. Generating these inputs requires collection of earthquake related information using present day techniques in seismology and geology, and processing the collected information to integrate it to arrive at a consolidated picture of the seismotectonics of the region. The earthquake problem in engineering design has been outlined in the context of a seismic design of nuclear power plants vis a vis current state of the art techniques. The extent to which the accepted procedures of assessing seismic risk in the region and generating the design inputs have been adherred to determine to a great extent the safety of the structures against future earthquakes. The document is a step towards developing an aproach for generating these inputs, which form the earthquake design basis. (author)

  18. Modeling risk and uncertainty in designing reverse logistics problem

    Directory of Open Access Journals (Sweden)

    Aida Nazari Gooran

    2018-01-01

    Full Text Available Increasing attention to environmental problems and social responsibility lead to appear reverse logistic (RL issues in designing supply chain which, in most recently, has received considerable attention from both academicians and practitioners. In this paper, a multi-product reverse logistic network design model is developed; then a hybrid method including Chance-constrained programming, Genetic algorithm and Monte Carlo simulation, are proposed to solve the developed model. The proposed model is solved for risk-averse and risk-seeking decision makers by conditional value at risk, sum of the excepted value and standard deviation, respectively. Comparisons of the results show that minimizing the costs had no direct relation with the kind of decision makers; however, in the most cases, risk-seeking decision maker gained more return products than risk-averse ones. It is clear that by increasing returned products to the chain, production costs of new products and material will be reduced and also by this act, environmental benefits will be created.

  19. Study of some physical aspects previous to design of an exponential experiment; Estudio de algunos aspectos fisicos previos al diseno de una experiencia exponencial

    Energy Technology Data Exchange (ETDEWEB)

    Caro, R.; Francisco, J. L. de

    1961-07-01

    This report presents the theoretical study of some physical aspects previous to the design of an exponential facility. The are: Fast and slow flux distribution in the multiplicative medium and in the thermal column, slowing down in the thermal column, geometrical distribution and minimum needed intensity of sources access channels and perturbations produced by possible variations in its position and intensity. (Author) 4 refs.

  20. Phase Transitions in Planning Problems: Design and Analysis of Parameterized Families of Hard Planning Problems

    Science.gov (United States)

    Hen, Itay; Rieffel, Eleanor G.; Do, Minh; Venturelli, Davide

    2014-01-01

    There are two common ways to evaluate algorithms: performance on benchmark problems derived from real applications and analysis of performance on parametrized families of problems. The two approaches complement each other, each having its advantages and disadvantages. The planning community has concentrated on the first approach, with few ways of generating parametrized families of hard problems known prior to this work. Our group's main interest is in comparing approaches to solving planning problems using a novel type of computational device - a quantum annealer - to existing state-of-the-art planning algorithms. Because only small-scale quantum annealers are available, we must compare on small problem sizes. Small problems are primarily useful for comparison only if they are instances of parametrized families of problems for which scaling analysis can be done. In this technical report, we discuss our approach to the generation of hard planning problems from classes of well-studied NP-complete problems that map naturally to planning problems or to aspects of planning problems that many practical planning problems share. These problem classes exhibit a phase transition between easy-to-solve and easy-to-show-unsolvable planning problems. The parametrized families of hard planning problems lie at the phase transition. The exponential scaling of hardness with problem size is apparent in these families even at very small problem sizes, thus enabling us to characterize even very small problems as hard. The families we developed will prove generally useful to the planning community in analyzing the performance of planning algorithms, providing a complementary approach to existing evaluation methods. We illustrate the hardness of these problems and their scaling with results on four state-of-the-art planners, observing significant differences between these planners on these problem families. Finally, we describe two general, and quite different, mappings of planning

  1. Design solutions to interface flow problems. Figures - Tables - Appendices

    International Nuclear Information System (INIS)

    1986-01-01

    All published proposals for the deep level burial of radioactive waste recognise that the access shafts, tunnels and boreholes must be sealed, and that the sealing of these openings plays an integral role in the overall isolation of the waste. Previous studies have identified the interface between the host ground formation and the various sealing materials as potential defects in the overall quality of the waste isolation. The significance of groundwater flow at and near the interface has been assessed for representative conditions in generic repository materials. A range of design options to minimise the significance of flow in the interface zone have been proposed, and the most practical of these options have been selected for quantitative analysis. It has been found that isolated high impermability collars are of limited value unless a highly effective method of minimising ground disturbance during excavation can be developed. It has also been found that control of radionuclide migration by sorptive processes provides an attractive option. The effect of various geometrical arrangements of sorptive materials has been investigated. Consideration has also been given to the particular conditions in the near field, to the behaviour of weak plastic clay host formations and to the mechanical interaction between the backfill material and the host formation

  2. Integer programming models and branch-and-cut approaches to generalized {0,1,2}-survivable network design problems.

    Science.gov (United States)

    Leitner, Markus

    In this article, we introduce the Generalized [Formula: see text]-Survivable Network Design Problem ([Formula: see text]-GSNDP) which has applications in the design of backbone networks. Different mixed integer linear programming formulations are derived by combining previous results obtained for the related [Formula: see text]-GSNDP and Generalized Network Design Problems. An extensive computational study comparing the correspondingly developed branch-and-cut approaches shows clear advantages for two particular variants. Additional insights into individual advantages and disadvantages of the developed algorithms for different instance characteristics are given.

  3. Efficient methods for solving discrete topology design problems in the PLATO-N project

    DEFF Research Database (Denmark)

    Canh, Nam Nguyen; Stolpe, Mathias

    This paper considers the general multiple load structural topology design problems in the framework of the PLATO-N project. The problems involve a large number of discrete design variables and were modeled as a non-convex mixed 0–1 program. For the class of problems considered, a global optimizat......This paper considers the general multiple load structural topology design problems in the framework of the PLATO-N project. The problems involve a large number of discrete design variables and were modeled as a non-convex mixed 0–1 program. For the class of problems considered, a global...

  4. Applications of Genetic Methods to NASA Design and Operations Problems

    Science.gov (United States)

    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.

  5. SOLUTION OF SIGNAL UNCERTAINTY PROBLEM AT ANALYTICAL DESIGN OF CONSECUTIVE COMPENSATOR IN PIEZO ACTUATOR CONTROL

    Directory of Open Access Journals (Sweden)

    S.V. Bystrov

    2016-05-01

    Full Text Available Subject of Research.We present research results for the signal uncertainty problem that naturally arises for the developers of servomechanisms, including analytical design of serial compensators, delivering the required quality indexes for servomechanisms. Method. The problem was solved with the use of Besekerskiy engineering approach, formulated in 1958. This gave the possibility to reduce requirements for input signal composition of servomechanisms by using only two of their quantitative characteristics, such as maximum speed and acceleration. Information about input signal maximum speed and acceleration allows entering into consideration the equivalent harmonic input signal with calculated amplitude and frequency. In combination with requirements for maximum tracking error, the amplitude and frequency of the equivalent harmonic effects make it possible to estimate analytically the value of the amplitude characteristics of the system by error and then convert it to amplitude characteristic of open-loop system transfer function. While previously Besekerskiy approach was mainly used in relation to the apparatus of logarithmic characteristics, we use this approach for analytical synthesis of consecutive compensators. Main Results. Proposed technique is used to create analytical representation of "input–output" and "error–output" polynomial dynamic models of the designed system. In turn, the desired model of the designed system in the "error–output" form of analytical representation of transfer functions is the basis for the design of consecutive compensator, that delivers the desired placement of state matrix eigenvalues and, consequently, the necessary set of dynamic indexes for the designed system. The given procedure of consecutive compensator analytical design on the basis of Besekerskiy engineering approach under conditions of signal uncertainty is illustrated by an example. Practical Relevance. The obtained theoretical results are

  6. The Great Deluge Algorithm applied to a nuclear reactor core design optimization problem

    International Nuclear Information System (INIS)

    Sacco, Wagner F.; Oliveira, Cassiano R.E. de

    2005-01-01

    The Great Deluge Algorithm (GDA) is a local search algorithm introduced by Dueck. It is an analogy with a flood: the 'water level' rises continuously and the proposed solution must lie above the 'surface' in order to survive. The crucial parameter is the 'rain speed', which controls convergence of the algorithm similarly to Simulated Annealing's annealing schedule. This algorithm is applied to the reactor core design optimization problem, which consists in adjusting several reactor cell parameters, such as dimensions, enrichment and materials, in order to minimize the average peak-factor in a 3-enrichment-zone reactor, considering restrictions on the average thermal flux, criticality and sub-moderation. This problem was previously attacked by the canonical genetic algorithm (GA) and by a Niching Genetic Algorithm (NGA). NGAs were designed to force the genetic algorithm to maintain a heterogeneous population throughout the evolutionary process, avoiding the phenomenon known as genetic drift, where all the individuals converge to a single solution. The results obtained by the Great Deluge Algorithm are compared to those obtained by both algorithms mentioned above. The three algorithms are submitted to the same computational effort and GDA reaches the best results, showing its potential for other applications in the nuclear engineering field as, for instance, the nuclear core reload optimization problem. One of the great advantages of this algorithm over the GA is that it does not require special operators for discrete optimization. (author)

  7. An Exploratory Study of Skin Problems Experienced by UK Nursing Home Residents Using Different Pad Designs.

    Science.gov (United States)

    Clarke-OʼNeill, Sinead; Farbrot, Anne; Lagerstedt, Marie-Louise; Cottenden, Alan; Fader, Mandy

    2015-01-01

    conditions was recorded that made classification difficult; the skin was often marked with creases from absorbent products, temporary marks, and pink/purple discoloration. We observed few cases of the severe erythema, rashes, and vesicles that are commonly used descriptors in previous skin tools. Nevertheless, the collected data reflect an abundance of skin problems that were difficult to categorize neatly. Researcher observations (method 1) showed that nearly all the residents (96%) had at least 1 IAD skin problem recorded over the 8-week period and 64% of residents had at least 1 problem that was rated as maximum severity. Healthcare assistants logged skin problems on 6.1% of pad changes. The discrepancy between researcher and healthcare assistant data appears to be largely due to healthcare assistants sometimes discounting low-grade IAD as normal for that population. Incontinence-associated dermatitis is common among nursing home residents who use incontinence pads, and it is often severe. No evidence was found that any design of pad was more likely than any others to be associated with skin problems. The method devised to enable healthcare assistants to record basic observational data on skin health in the diaper area at each pad change (Method 2) proved simple to use but still resulted in substantial underreporting of IAD, suggesting that further work is needed to develop a tool that more successfully encourages them to log and treat IAD problems.

  8. Case-Based Reasoning and Instructional Design: Using Stories To Support Problem Solving.

    Science.gov (United States)

    Jonassen, David H.; Hernandez-Serrano, Julian

    2002-01-01

    Discusses the increased emphasis on problem solving and problem-based learning in instructional design and the need for new methods for task analysis and models for designing instruction. Defines the rationale and means for analyzing, organizing, and presenting stories to support problem solving by case-based reasoning. (Author/LRW)

  9. Computational chemical product design problems under property uncertainties

    DEFF Research Database (Denmark)

    Frutiger, Jerome; Cignitti, Stefano; Abildskov, Jens

    2017-01-01

    Three different strategies of how to combine computational chemical product design with Monte Carlo based methods for uncertainty analysis of chemical properties are outlined. One method consists of a computer-aided molecular design (CAMD) solution and a post-processing property uncertainty...

  10. Design as Key to Unlock the Wicked Problem of Sustainability

    DEFF Research Database (Denmark)

    Skjold, Else; Ræbild, Ulla; Hasling, Karen Marie

    2017-01-01

    How might we as researchers within the design community reach out and create new knowledge and value in close collaboration with a company, and at the same time contribute to a sustainable development? In this paper, we address the question of How and with whom do we re-do, by proposing multiple...... case on which the paper builds and account for the applied multiple perspectives research design. Lastly, we discuss how the construct has supported a less compartmentalised understanding of sustainability within the company, and furthered insights on how design can be a driver for sustainability...... perspectives research as a way to unlock the potential of design thinking as a fundamentally integrative discipline. Hence, the aim of the paper is to show and discuss the ways in which a research design constructed by several perspectives can enable an actual impact. We will present the company collaboration...

  11. Technologists Talk: Making the Links between Design, Problem-Solving and Experiences with Hard Materials

    Science.gov (United States)

    Potter, Patricia

    2013-01-01

    Design and problem-solving is a key learning focus in technology education and remains a distinguishing factor that separates it from other subject areas. This research investigated how two expert designers considered experiences with hard materials contributed to their learning design and problem-solving with these materials. The research project…

  12. Acceleration of solving the dynamic multi-objective network design problem using response surface methods

    NARCIS (Netherlands)

    Wismans, Luc Johannes Josephus; van Berkum, Eric C.; Bliemer, M.C.J.

    2014-01-01

    Optimization of externalities and accessibility using dynamic traffic management measures on a strategic level is a specific example of solving a multi-objective network design problem. Solving this optimization problem is time consuming, because heuristics like evolutionary multi objective

  13. Invisibility problem in acoustics, electromagnetism and heat transfer. Inverse design method

    Science.gov (United States)

    Alekseev, G.; Tokhtina, A.; Soboleva, O.

    2017-10-01

    Two approaches (direct design and inverse design methods) for solving problems of designing devices providing invisibility of material bodies of detection using different physical fields - electromagnetic, acoustic and static are discussed. The second method is applied for solving problems of designing cloaking devices for the 3D stationary thermal scattering model. Based on this method the design problems under study are reduced to respective control problems. The material parameters (radial and tangential heat conductivities) of the inhomogeneous anisotropic medium filling the thermal cloak and the density of auxiliary heat sources play the role of controls. A unique solvability of direct thermal scattering problem in the Sobolev space is proved and the new estimates of solutions are established. Using these results, the solvability of control problem is proved and the optimality system is derived. Based on analysis of optimality system, the stability estimates of optimal solutions are established and numerical algorithms for solving particular thermal cloaking problem are proposed.

  14. Experimental Design of a Polymeric Solution to Improve the Mobility Ratio in a Reservoir previous implementation of a pilot project of EOR

    Directory of Open Access Journals (Sweden)

    Vanessa Cuenca

    2016-12-01

    Full Text Available This paper describes experimental formulations of polymeric solutions through lab evaluations with the objective of finding optimum solution concentration to fluid mobility in reservoirs as previous step before implementing a pilot project of enhanced oil recovery. The polymers, firstly, were selected based on the properties from fluids from reservoir. Two types of polymers were used TCC-330 and EOR909 and the experimental tests were: thermal stability, compatibility, adsorption, salinity, and displacement. The design with the best results was with polymer TCC-330 at 1,500 ppm concentration.

  15. Designing cases in problem-based learning to foster problem-solving skill.

    Science.gov (United States)

    Lohman, Margaret C; Finkelstein, Michael

    2002-08-01

    The purpose of this study was to examine the effect of case segmentation schemes in problem-based learning (PBL) on the development of problem-solving skill, self-directedness and technical knowledge. Seventy-four dental education students were randomly assigned to 12 PBL groups. Six groups experienced PBL cases that were formatted in short segments and six groups experienced PBL cases that were formatted in long segments. Pretest measures of problem-solving skill, self-directedness and technical knowledge were administered at the beginning of the Fall 1998 semester. Students studied three PBL cases in their assigned groups in the ensuing semester. Posttest measures were administered at the conclusion of the semester. Analysis of the data found that students who experienced PBL with a short case segmentation scheme were better able to solve problems highly similar to the problems in the teaching cases than students who experienced PBL with a long case segmentation scheme. No significant differences were found for self-directedness, technical knowledge, or ability to solve problems distinctly different from the teaching cases. Explanations of these findings and their implications for research and practice in PBL are discussed.

  16. Designing WebQuests to Support Creative Problem Solving

    Science.gov (United States)

    Rubin, Jim

    2013-01-01

    WebQuests have been a popular alternative for collaborative group work that utilizes internet resources, but studies have questioned how effective they are in challenging students to use higher order thinking processes that involve creative problem solving. This article explains how different levels of inquiry relate to categories of learning…

  17. Multiphysics field analysis and multiobjective design optimization: a benchmark problem

    Czech Academy of Sciences Publication Activity Database

    di Barba, P.; Doležel, Ivo; Karban, P.; Kůs, P.; Mach, F.; Mognaschi, M. E.; Savini, A.

    2014-01-01

    Roč. 22, č. 7 (2014), s. 1214-1225 ISSN 1741-5977 R&D Projects: GA ČR(CZ) GAP102/11/0498 Institutional support: RVO:61388998 Keywords : coupled-field problems * finite-element analysis * hp-FEM adaptation Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 0.868, year: 2014

  18. A school-based program implemented by community providers previously trained for the prevention of eating and weight-related problems in secondary-school adolescents: the MABIC study protocol

    Science.gov (United States)

    2013-01-01

    Background The prevention of eating disorders and disordered eating are increasingly recognized as public health priorities. Challenges in this field included moving from efficacy to effectiveness and developing an integrated approach to the prevention of a broad spectrum of eating and weight-related problems. A previous efficacy trial indicated that a universal disordered eating prevention program, based on the social cognitive model, media literacy educational approach and cognitive dissonance theory, reduced risk factors for disordered eating, but it is unclear whether this program has effects under more real-world conditions. The main aim of this effectiveness trial protocol is to test whether this program has effects when incorporating an integrated approach to prevention and when previously-trained community providers implement the intervention. Methods/design The research design involved a multi-center non-randomized controlled trial with baseline, post and 1-year follow-up measures. Six schools from the city of Sabadell (close to Barcelona) participated in the intervention group, and eleven schools from four towns neighboring Sabadell participated in the control group. A total of 174 girls and 180 boys in the intervention group, and 484 girls and 490 boys in the control group were registered in class lists prior to baseline. A total of 18 community providers, secondary-school class tutors, nurses from the Catalan Government’s Health and School Program, and health promotion technicians from Sabadell City Council were trained and delivered the program. Shared risk factors of eating and weight-related problems were assessed as main measures. Discussion It will be vital for progress in disordered eating prevention to conduct effectiveness trials, which test whether interventions are effective when delivered by community providers under ecologically valid conditions, as opposed to tightly controlled research trials. The MABIC project will provide new

  19. A hierarchical method for structural topology design problems with local stress and displacement constraints

    DEFF Research Database (Denmark)

    Stolpe, Mathias; Stidsen, Thomas K.

    2005-01-01

    In this paper we present a hierarchical optimization method for finding feasible true 0-1 solutions to finite element based topology design problems. The topology design problems are initially modeled as non-convex mixed 0-1 programs. The hierarchical optimization method is applied to the problem...... from global optimization, which have only recently become available, for solving the problems in the sequence. Numerical examples of topology design problems of continuum structures with local stress and displacement constraints are presented.......In this paper we present a hierarchical optimization method for finding feasible true 0-1 solutions to finite element based topology design problems. The topology design problems are initially modeled as non-convex mixed 0-1 programs. The hierarchical optimization method is applied to the problem...... of minimizing the weight of a structure subject to displacement and local design-dependent stress constraints. The method iteratively solves a sequence of problems of increasing size of the same type as the original problem. The problems are defined on a design mesh which is initially coarse...

  20. Why we Need to Distinguish between Problem Solving Types in Information Systems Design

    OpenAIRE

    Stergiou, Maria; Johnson, Leslie

    1999-01-01

    This report aims to provide the basic vocabulary and illuminate the issues associated with the nature of problem types. The concepts presented come from the writings of R. Cyert and J. March and refer to the three types of problems that organisations face. Each type of problem will be illustrated along with its appropriate problem solving process. The impact of the types of problems to the design and development of Information Systems is discussed. The report provides a starter set of referen...

  1. Sensitivity computation of the l1 minimization problem and its application to dictionary design of ill-posed problems

    International Nuclear Information System (INIS)

    Horesh, L; Haber, E

    2009-01-01

    The l 1 minimization problem has been studied extensively in the past few years. Recently, there has been a growing interest in its application for inverse problems. Most studies have concentrated in devising ways for sparse representation of a solution using a given prototype dictionary. Very few studies have addressed the more challenging problem of optimal dictionary construction, and even these were primarily devoted to the simplistic sparse coding application. In this paper, sensitivity analysis of the inverse solution with respect to the dictionary is presented. This analysis reveals some of the salient features and intrinsic difficulties which are associated with the dictionary design problem. Equipped with these insights, we propose an optimization strategy that alleviates these hurdles while utilizing the derived sensitivity relations for the design of a locally optimal dictionary. Our optimality criterion is based on local minimization of the Bayesian risk, given a set of training models. We present a mathematical formulation and an algorithmic framework to achieve this goal. The proposed framework offers the design of dictionaries for inverse problems that incorporate non-trivial, non-injective observation operators, where the data and the recovered parameters may reside in different spaces. We test our algorithm and show that it yields improved dictionaries for a diverse set of inverse problems in geophysics and medical imaging

  2. The gravitational attraction algorithm: a new metaheuristic applied to a nuclear reactor core design optimization problem

    International Nuclear Information System (INIS)

    Sacco, Wagner F.; Oliveira, Cassiano R.E. de

    2005-01-01

    A new metaheuristic called 'Gravitational Attraction Algorithm' (GAA) is introduced in this article. It is an analogy with the gravitational force field, where a body attracts another proportionally to both masses and inversely to their distances. The GAA is a populational algorithm where, first of all, the solutions are clustered using the Fuzzy Clustering Means (FCM) algorithm. Following that, the gravitational forces of the individuals in relation to each cluster are evaluated and this individual or solution is displaced to the cluster with the greatest attractive force. Once it is inside this cluster, the solution receives small stochastic variations, performing a local exploration. Then the solutions are crossed over and the process starts all over again. The parameters required by the GAA are the 'diversity factor', which is used to create a random diversity in a fashion similar to genetic algorithm's mutation, and the number of clusters for the FCM. GAA is applied to the reactor core design optimization problem which consists in adjusting several reactor cell parameters in order to minimize the average peak-factor in a 3-enrichment-zone reactor, considering operational restrictions. This problem was previously attacked using the canonical genetic algorithm (GA) and a Niching Genetic Algorithm (NGA). The new metaheuristic is then compared to those two algorithms. The three algorithms are submitted to the same computational effort and GAA reaches the best results, showing its potential for other applications in the nuclear engineering field as, for instance, the nuclear core reload optimization problem. (author)

  3. Coarse-grained parallel genetic algorithm applied to a nuclear reactor core design optimization problem

    International Nuclear Information System (INIS)

    Pereira, Claudio M.N.A.; Lapa, Celso M.F.

    2003-01-01

    This work extends the research related to generic algorithms (GA) in core design optimization problems, which basic investigations were presented in previous work. Here we explore the use of the Island Genetic Algorithm (IGA), a coarse-grained parallel GA model, comparing its performance to that obtained by the application of a traditional non-parallel GA. The optimization problem consists on adjusting several reactor cell parameters, such as dimensions, enrichment and materials, in order to minimize the average peak-factor in a 3-enrichment zone reactor, considering restrictions on the average thermal flux, criticality and sub-moderation. Our IGA implementation runs as a distributed application on a conventional local area network (LAN), avoiding the use of expensive parallel computers or architectures. After exhaustive experiments, taking more than 1500 h in 550 MHz personal computers, we have observed that the IGA provided gains not only in terms of computational time, but also in the optimization outcome. Besides, we have also realized that, for such kind of problem, which fitness evaluation is itself time consuming, the time overhead in the IGA, due to the communication in LANs, is practically imperceptible, leading to the conclusion that the use of expensive parallel computers or architecture can be avoided

  4. Overview of the service life and maintenance problem probabilistic design

    NARCIS (Netherlands)

    Siemes, A.J.M.

    2002-01-01

    The service life of a building or structure is determined by the design and construction in combination with the ageing and the maintenance during use. To get grip on this combination it has advantage to present the functioning of the building or the structure on a performance level. As ageing will

  5. Radar signal design problem with neural network processing

    Indian Academy of Sciences (India)

    Unknown

    Abstract. Binary and ternary sequences with peaky autocorrelation, measured in terms of high discrimination and merit factor have been searched earlier, using optimization techniques. It is shown that the use of neural network processing of the return signal is much more advantageous. It opens up a new signal design ...

  6. Optimal Experimental Design for Large-Scale Bayesian Inverse Problems

    KAUST Repository

    Ghattas, Omar

    2014-01-06

    We develop a Bayesian framework for the optimal experimental design of the shock tube experiments which are being carried out at the KAUST Clean Combustion Research Center. The unknown parameters are the pre-exponential parameters and the activation energies in the reaction rate expressions. The control parameters are the initial mixture composition and the temperature. The approach is based on first building a polynomial based surrogate model for the observables relevant to the shock tube experiments. Based on these surrogates, a novel MAP based approach is used to estimate the expected information gain in the proposed experiments, and to select the best experimental set-ups yielding the optimal expected information gains. The validity of the approach is tested using synthetic data generated by sampling the PC surrogate. We finally outline a methodology for validation using actual laboratory experiments, and extending experimental design methodology to the cases where the control parameters are noisy.

  7. Alloy design as an inverse problem of cluster expansion models

    DEFF Research Database (Denmark)

    Larsen, Peter Mahler; Kalidindi, Arvind R.; Schmidt, Søren

    2017-01-01

    Central to a lattice model of an alloy system is the description of the energy of a given atomic configuration, which can be conveniently developed through a cluster expansion. Given a specific cluster expansion, the ground state of the lattice model at 0 K can be solved by finding the configurat......Central to a lattice model of an alloy system is the description of the energy of a given atomic configuration, which can be conveniently developed through a cluster expansion. Given a specific cluster expansion, the ground state of the lattice model at 0 K can be solved by finding...... the inverse problem in terms of energetically distinct configurations, using a constraint satisfaction model to identify constructible configurations, and show that a convex hull can be used to identify ground states. To demonstrate the approach, we solve for all ground states for a binary alloy in a 2D...

  8. A school-based program implemented by community providers previously trained for the prevention of eating and weight-related problems in secondary-school adolescents: the MABIC study protocol.

    Science.gov (United States)

    Sánchez-Carracedo, David; López-Guimerà, Gemma; Fauquet, Jordi; Barrada, Juan Ramón; Pàmias, Montserrat; Puntí, Joaquim; Querol, Mireia; Trepat, Esther

    2013-10-12

    The prevention of eating disorders and disordered eating are increasingly recognized as public health priorities. Challenges in this field included moving from efficacy to effectiveness and developing an integrated approach to the prevention of a broad spectrum of eating and weight-related problems. A previous efficacy trial indicated that a universal disordered eating prevention program, based on the social cognitive model, media literacy educational approach and cognitive dissonance theory, reduced risk factors for disordered eating, but it is unclear whether this program has effects under more real-world conditions. The main aim of this effectiveness trial protocol is to test whether this program has effects when incorporating an integrated approach to prevention and when previously-trained community providers implement the intervention. The research design involved a multi-center non-randomized controlled trial with baseline, post and 1-year follow-up measures. Six schools from the city of Sabadell (close to Barcelona) participated in the intervention group, and eleven schools from four towns neighboring Sabadell participated in the control group. A total of 174 girls and 180 boys in the intervention group, and 484 girls and 490 boys in the control group were registered in class lists prior to baseline. A total of 18 community providers, secondary-school class tutors, nurses from the Catalan Government's Health and School Program, and health promotion technicians from Sabadell City Council were trained and delivered the program. Shared risk factors of eating and weight-related problems were assessed as main measures. It will be vital for progress in disordered eating prevention to conduct effectiveness trials, which test whether interventions are effective when delivered by community providers under ecologically valid conditions, as opposed to tightly controlled research trials. The MABIC project will provide new contributions in this transition from efficacy

  9. Application of Decomposition Methodology to Solve Integrated Process Design and Controller Design Problems for Reactor-Separator-Recycle System

    DEFF Research Database (Denmark)

    Abd.Hamid, Mohd-Kamaruddin; Sin, Gürkan; Gani, Rafiqul

    2010-01-01

    This paper presents the integrated process design and controller design (IPDC) for a reactor-separator-recycle (RSR) system and evaluates a decomposition methodology to solve the IPDC problem. Accordingly, the IPDC problem is solved by decomposing it into four hierarchical stages: (i) pre-analysis......, (ii) design analysis, (iii) controller design analysis, and (iv) final selection and verification. The methodology makes use of thermodynamic-process insights and the reverse design approach to arrive at the final process-controller design decisions. The developed methodology is illustrated through...... the design of a RSR system involving consecutive reactions, A B -> C and shown to provide effective solutions that satisfy design, control and cost criteria. The advantage of the proposed methodology is that it is systematic, makes use of thermodynamic-process knowledge and provides valuable insights...

  10. A Matheuristic for the Liner Shipping Network Design Problem with Transit Time Restrictions

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Desaulniers, Guy; Karsten, Christian Vad

    2015-01-01

    We present a mathematical model for the liner shipping network design problem with transit time restrictions on the cargo flow. We extend an existing matheuristic for the liner shipping network design problem to consider transit time restrictions. The matheuristic is an improvement heuristic, where...

  11. A hierarchical method for discrete structural topology design problems with local stress and displacement constraints

    DEFF Research Database (Denmark)

    Stolpe, Mathias; Stidsen, Thomas K.

    2007-01-01

    and then successively refined as needed. At each level of design mesh refinement, a neighbourhood optimization method is used to treat the problem considered. The non-convex topology design problems are equivalently reformulated as convex all-quadratic mixed 0-1 programs. This reformulation enables the use of methods...

  12. A Branch and Cut algorithm for the container shipping network design problem

    DEFF Research Database (Denmark)

    Reinhardt, Line Blander; Pisinger, David

    2012-01-01

    The network design problem in liner shipping is of increasing importance in a strongly competitive market where potential cost reductions can influence market share and profits significantly. In this paper the network design and fleet assignment problems are combined into a mixed integer linear p...... transhipment cost. The problem is solved with branch-and-cut using clover and transhipment inequalities. Computational results are reported for instances with up to 15 ports....

  13. A Branch and Cut algorithm for the container shipping network design problem

    DEFF Research Database (Denmark)

    Reinhardt, Line Blander; Kallehauge, Brian; Pisinger, David

    The network design problem in liner shipping is of increasing importance in a strongly competitive market where potential cost reductions can influence market share and profits significantly. In this paper the network design and fleet assignment problems are combined into a mixed integer linear p...... transhipment cost. The problem is solved with branch-and-cut using clover and transhipment inequalities. Computational results are reported for instances with up to 15 ports....

  14. Arch-pattern based design and aspect-oriented implementation of Readers-Writers concurrent problem

    Directory of Open Access Journals (Sweden)

    Dumitru Ciorbă

    2007-11-01

    Full Text Available The classical problems of concurrent programming start from the design problems of operating systems in the 80-s. But today there are still proposed new solutions for these problems with the help of various design and programming approaches. The present article describes a solution which was designed according to some new object-oriented principles, based on design patterns and proposes two program solutions: firstly - an object-oriented implementation in Java language, the secondly – an aspect-oriented one in AspectJ language.

  15. Multi-objective optimization of generalized reliability design problems using feature models-A concept for early design stages

    International Nuclear Information System (INIS)

    Limbourg, Philipp; Kochs, Hans-Dieter

    2008-01-01

    Reliability optimization problems such as the redundancy allocation problem (RAP) have been of considerable interest in the past. However, due to the restrictions of the design space formulation, they may not be applicable in all practical design problems. A method with high modelling freedom for rapid design screening is desirable, especially in early design stages. This work presents a novel approach to reliability optimization. Feature modelling, a specification method originating from software engineering, is applied for the fast specification and enumeration of complex design spaces. It is shown how feature models can not only describe arbitrary RAPs but also much more complex design problems. The design screening is accomplished by a multi-objective evolutionary algorithm for probabilistic objectives. Comparing averages or medians may hide the true characteristics of this distributions. Therefore the algorithm uses solely the probability of a system dominating another to achieve the Pareto optimal set. We illustrate the approach by specifying a RAP and a more complex design space and screening them with the evolutionary algorithm

  16. Using Analytics to Transform a Problem-Based Case Library: An Educational Design Research Approach

    Science.gov (United States)

    Schmidt, Matthew; Tawfik, Andrew A.

    2018-01-01

    This article describes the iterative design, development, and evaluation of a case-based learning environment focusing on an ill-structured sales management problem. We discuss our processes and situate them within the broader framework of educational design research. The learning environment evolved over the course of three design phases. A…

  17. Gradient vs. approximation design optimization techniques in low-dimensional convex problems

    Science.gov (United States)

    Fedorik, Filip

    2013-10-01

    Design Optimization methods' application in structural designing represents a suitable manner for efficient designs of practical problems. The optimization techniques' implementation into multi-physical softwares permits designers to utilize them in a wide range of engineering problems. These methods are usually based on modified mathematical programming techniques and/or their combinations to improve universality and robustness for various human and technical problems. The presented paper deals with the analysis of optimization methods and tools within the frame of one to three-dimensional strictly convex optimization problems, which represent a component of the Design Optimization module in the Ansys program. The First Order method, based on combination of steepest descent and conjugate gradient method, and Supbproblem Approximation method, which uses approximation of dependent variables' functions, accompanying with facilitation of Random, Sweep, Factorial and Gradient Tools, are analyzed, where in different characteristics of the methods are observed.

  18. A multilevel, level-set method for optimizing eigenvalues in shape design problems

    International Nuclear Information System (INIS)

    Haber, E.

    2004-01-01

    In this paper, we consider optimal design problems that involve shape optimization. The goal is to determine the shape of a certain structure such that it is either as rigid or as soft as possible. To achieve this goal we combine two new ideas for an efficient solution of the problem. First, we replace the eigenvalue problem with an approximation by using inverse iteration. Second, we use a level set method but rather than propagating the front we use constrained optimization methods combined with multilevel continuation techniques. Combining these two ideas we obtain a robust and rapid method for the solution of the optimal design problem

  19. A Mixed Integer Efficient Global Optimization Framework: Applied to the Simultaneous Aircraft Design, Airline Allocation and Revenue Management Problem

    Science.gov (United States)

    Roy, Satadru

    Traditional approaches to design and optimize a new system, often, use a system-centric objective and do not take into consideration how the operator will use this new system alongside of other existing systems. This "hand-off" between the design of the new system and how the new system operates alongside other systems might lead to a sub-optimal performance with respect to the operator-level objective. In other words, the system that is optimal for its system-level objective might not be best for the system-of-systems level objective of the operator. Among the few available references that describe attempts to address this hand-off, most follow an MDO-motivated subspace decomposition approach of first designing a very good system and then provide this system to the operator who decides the best way to use this new system along with the existing systems. The motivating example in this dissertation presents one such similar problem that includes aircraft design, airline operations and revenue management "subspaces". The research here develops an approach that could simultaneously solve these subspaces posed as a monolithic optimization problem. The monolithic approach makes the problem a Mixed Integer/Discrete Non-Linear Programming (MINLP/MDNLP) problem, which are extremely difficult to solve. The presence of expensive, sophisticated engineering analyses further aggravate the problem. To tackle this challenge problem, the work here presents a new optimization framework that simultaneously solves the subspaces to capture the "synergism" in the problem that the previous decomposition approaches may not have exploited, addresses mixed-integer/discrete type design variables in an efficient manner, and accounts for computationally expensive analysis tools. The framework combines concepts from efficient global optimization, Kriging partial least squares, and gradient-based optimization. This approach then demonstrates its ability to solve an 11 route airline network

  20. The gravitational attraction algorithm: a new metaheuristic applied to a nuclear reactor core design optimization problem

    Energy Technology Data Exchange (ETDEWEB)

    Sacco, Wagner F.; Oliveira, Cassiano R.E. de [Georgia Institute of Technology, Atlanta, GA (United States). George W. Woodruff School of Mechanical Engineering. Nuclear and Radiological Engineering Program]. E-mail: wagner.sacco@me.gatech.edu; cassiano.oliveira@nre.gatech.edu; Pereira, Claudio M.N.A. [Instituto de Engenharia Nuclear (IEN), Rio de Janeiro, RJ (Brazil)]. E-mail: cmnap@ien.gov.br

    2005-07-01

    A new metaheuristic called 'Gravitational Attraction Algorithm' (GAA) is introduced in this article. It is an analogy with the gravitational force field, where a body attracts another proportionally to both masses and inversely to their distances. The GAA is a populational algorithm where, first of all, the solutions are clustered using the Fuzzy Clustering Means (FCM) algorithm. Following that, the gravitational forces of the individuals in relation to each cluster are evaluated and this individual or solution is displaced to the cluster with the greatest attractive force. Once it is inside this cluster, the solution receives small stochastic variations, performing a local exploration. Then the solutions are crossed over and the process starts all over again. The parameters required by the GAA are the 'diversity factor', which is used to create a random diversity in a fashion similar to genetic algorithm's mutation, and the number of clusters for the FCM. GAA is applied to the reactor core design optimization problem which consists in adjusting several reactor cell parameters in order to minimize the average peak-factor in a 3-enrichment-zone reactor, considering operational restrictions. This problem was previously attacked using the canonical genetic algorithm (GA) and a Niching Genetic Algorithm (NGA). The new metaheuristic is then compared to those two algorithms. The three algorithms are submitted to the same computational effort and GAA reaches the best results, showing its potential for other applications in the nuclear engineering field as, for instance, the nuclear core reload optimization problem. (author)

  1. A Heuristic Design Information Sharing Framework for Hard Discrete Optimization Problems

    National Research Council Canada - National Science Library

    Jacobson, Sheldon H

    2007-01-01

    .... This framework has been used to gain new insights into neighborhood structure designs that allow different neighborhood functions to share information when using the same heuristic applied to the same problem...

  2. Numerical methods for the design of large-scale nonlinear discrete ill-posed inverse problems

    International Nuclear Information System (INIS)

    Haber, E; Horesh, L; Tenorio, L

    2010-01-01

    Design of experiments for discrete ill-posed problems is a relatively new area of research. While there has been some limited work concerning the linear case, little has been done to study design criteria and numerical methods for ill-posed nonlinear problems. We present an algorithmic framework for nonlinear experimental design with an efficient numerical implementation. The data are modeled as indirect, noisy observations of the model collected via a set of plausible experiments. An inversion estimate based on these data is obtained by a weighted Tikhonov regularization whose weights control the contribution of the different experiments to the data misfit term. These weights are selected by minimization of an empirical estimate of the Bayes risk that is penalized to promote sparsity. This formulation entails a bilevel optimization problem that is solved using a simple descent method. We demonstrate the viability of our design with a problem in electromagnetic imaging based on direct current resistivity and magnetotelluric data

  3. ALE-PSO: An Adaptive Swarm Algorithm to Solve Design Problems of Laminates

    Directory of Open Access Journals (Sweden)

    Paolo Vannucci

    2009-04-01

    Full Text Available This paper presents an adaptive PSO algorithm whose numerical parameters can be updated following a scheduled protocol respecting some known criteria of convergence in order to enhance the chances to reach the global optimum of a hard combinatorial optimization problem, such those encountered in global optimization problems of composite laminates. Some examples concerning hard design problems are provided, showing the effectiveness of the approach.

  4. Accelerating solving the dynamic multi-objective nework design problem using response surface methods

    NARCIS (Netherlands)

    Wismans, Luc Johannes Josephus; van Berkum, Eric C.; Bliemer, Michiel C.J.; Viti, F.; Immers, B.; Tampere, C.

    2011-01-01

    Multi objective optimization of externalities of traffic solving a network design problem in which Dynamic Traffic Management measures are used, is time consuming while heuristics are needed and solving the lower level requires solving the dynamic user equilibrium problem. Use of response surface

  5. Design and Evaluation of a Problem-Based Learning Environment for Teacher Training

    Science.gov (United States)

    Hemker, Laura; Prescher, Claudia; Narciss, Susanne

    2017-01-01

    Problem-based learning can have a great impact on the acquisition of practical knowledge, which is a central learning aim in the field of teacher education. Therefore, we implemented a problem-based learning approach in four seminars on educational assessment. In this paper, we outline our didactic design and discuss the results of the first…

  6. Design of a Problem-Based Online Learning Environment and Evaluation of Its Effectiveness

    Science.gov (United States)

    Gündüz, Abdullah Yasin; Alemdag, Ecenaz; Yasar, Sevil; Erdem, Mukaddes

    2016-01-01

    Problem-based learning approach presents several advantages such as improving students' engagement in learning and fostering their higher-order thinking skills. Although there is a plethora of research regarding implementation of problem-based learning in classrooms, its design and application process for web-based environments need further…

  7. Pemahaman Critical Thinking, Design Thinking dan Problem Solving dalam Proses Desain

    Directory of Open Access Journals (Sweden)

    Yunida Sofiana

    2014-10-01

    Full Text Available The task of the designer is not limited to beautify the aesthetic appearance of a form, but more complex and down to the root of the problem. Based on observations made at the educational institution, all this time, the process of designing is carried out in the world of education, discusses the more common problems and it simply just to beautify a form. The purpose of this study is to revitalize the importance of the design process that is accompanied by a pattern of critical and creative thinking in finding solutions to design problems. So that the resulting design, and variations will have a better quality after going through deeper thinking. The research method is descriptive-qualitative research that are taken from various sources of books, internet and student assignments. The data are summarized and analyzed and made a conclusion. 

  8. Innovative method by design-around concepts with integrating the algorithm for inventive problem solving

    International Nuclear Information System (INIS)

    Chen, Wang Chih; Chen Jahau Lewis

    2014-01-01

    The work proposes a new design tool that integrates design-around concepts with the algorithm for inventive problem solving (Russian acronym: ARIZ). ARIZ includes a complete procedure for analyzing problems and related resource, resolving conflicts and generating solutions. The combination of ARIZ and design-around concepts and understanding identified principles that govern patent infringements can prevent patent infringements whenever designers innovate, greatly reducing the cost and time associated with the product design stage. The presented tool is developed from an engineering perspective rather than a legal perspective, and so can help designers easily to prevent patent infringements and succeed in innovating by designing around. An example is used to demonstrate the proposed method.

  9. A Branch and Bound Approach for Truss Topology Design Problems with Valid Inequalities

    International Nuclear Information System (INIS)

    Cerveira, Adelaide; Agra, Agostinho; Bastos, Fernando; Varum, Humberto

    2010-01-01

    One of the classical problems in the structural optimization field is the Truss Topology Design Problem (TTDP) which deals with the selection of optimal configuration for structural systems for applications in mechanical, civil, aerospace engineering, among others. In this paper we consider a TTDP where the goal is to find the stiffest truss, under a given load and with a bound on the total volume. The design variables are the cross-section areas of the truss bars that must be chosen from a given finite set. This results in a large-scale non-convex problem with discrete variables. This problem can be formulated as a Semidefinite Programming Problem (SDP problem) with binary variables. We propose a branch and bound algorithm to solve this problem. In this paper it is considered a binary formulation of the problem, to take advantage of its structure, which admits a Knapsack problem as subproblem. Thus, trying to improve the performance of the Branch and Bound, at each step, some valid inequalities for the Knapsack problem are included.

  10. State-space solutions to the h_inf/ltr design problem

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik

    1993-01-01

    phase case, though, the order of the controllers can be reduced to n in all cases. The control problems corresponding to the various controller types are given as four different singular state-space problems, and the solutions are given in terms of the relevant equations and inequalities......The LTR design problem using an JC optimality criterion is presented for two types of recovery errors, the sensitivity recovery error and the input-output recovery error. For both errors two different approaches are presented. First, following the classical LTR design philosophy, a Luenberger...

  11. Design as a Problem and Design as a Solution for Sustainability

    DEFF Research Database (Denmark)

    Morelli, Nicola

    2012-01-01

    The role of industrial design has been essential in the definition of an industrial model based on large production volumes for broad markets, but industrial designers also contributed to the maturation of such a model towards sophisticated models that are now proving to be unsustainable. This made...

  12. Seven-Step Problem-Based Learning in an Interaction Design Course

    Science.gov (United States)

    Schultz, Nette; Christensen, Hans Peter

    2004-01-01

    The objective in this paper is the implementation of the highly structured seven-step problem-based learning (PBL) procedure as part of the learning process in a human-computer interaction (HCI) design course at the Technical University of Denmark, taking into account the common learning processes in PBL and the interaction design process. These…

  13. Integration and the hold-up problem in the design organization for engineering projects

    NARCIS (Netherlands)

    Zerjav, Vedran; Hartmann, Timo; Javernick-Will, A.; Chinowsky, P.

    2012-01-01

    The paper presents a perspective of the design organization in engineering projects based on the economic concept of the hold-up problem. By integrating the economic theories on the boundaries of organizations into the existing knowledge on design in engineering projects, the paper hypothesizes a

  14. Optimizing Supply Chain Collaboration Based on Agreement Buyer-Supplier Relationship with Network Design Problem

    OpenAIRE

    Wahyudi Sutopo; Ayu Erliza; Arien Heryansyah

    2016-01-01

    In recent years, the rising competitive environment with shorter product life cycles and high customization forces industries to increase their flexibility, speed up their response, and enhance concurrent engineering designs. To integrate these prospects, supply chain collaboration becomes a pertinent strategy for industries to strengthen their competitiveness. The network design problem is used to implement supply chain collaboration. In the buying and...

  15. Design based Investigation on Construction of Mathematical Modelling Problems: Example of Financial Content

    Directory of Open Access Journals (Sweden)

    Melike TURAL SÖNMEZ

    2017-12-01

    Full Text Available The purpose of this study is to examine the construction of mathematical modelling problems process in the content of financial literacy. It is also aimed to create design proposals for construction of mathematical modelling problems. A design based research method was used in this study. The participants were three seventh grade students, six finance experts and nine mathematics education experts. Data collection tools were transcription of video and tapes group discussions, presentations and worksheets during mathematical modelling activities, and participant experts’ feedback form about mathematical modelling problems. There were three stages in this study. First stage was application of preliminary study. This stage gave information about convenience of problems to grade level, students’ timing for solution of problems, clarity of problems and students’ background about content. In second stage, finance experts commented on convenience of mathematical modelling problems to financial literacy standards. In third stage, mathematics education experts commented on convenience of problems to students’ grade level, mathematical modelling principles and seventh grade mathematics lesson objectives. They also gave suggestion on progress. The frequency value of theme in feedback forms was calculated and experts’ expressions were given as citation. It was given suggestion about stages and application of the design guide

  16. Design of a Generic and Flexible Data Structure for Efficient Formulation of Large Scale Network Problems

    DEFF Research Database (Denmark)

    Quaglia, Alberto; Sarup, Bent; Sin, Gürkan

    2013-01-01

    The formulation of Enterprise-Wide Optimization (EWO) problems as mixed integer nonlinear programming requires collecting, consolidating and systematizing large amount of data, coming from different sources and specific to different disciplines. In this manuscript, a generic and flexible data...... structure for efficient formulation of enterprise-wide optimization problems is presented. Through the integration of the described data structure in our synthesis and design framework, the problem formulation workflow is automated in a software tool, reducing time and resources needed to formulate large...... problems, while ensuring at the same time data consistency and quality at the application stage....

  17. The Total Synthesis Problem of linear multivariable control. II - Unity feedback and the design morphism

    Science.gov (United States)

    Sain, M. K.; Antsaklis, P. J.; Gejji, R. R.; Wyman, B. F.; Peczkowski, J. L.

    1981-01-01

    Zames (1981) has observed that there is, in general, no 'separation principle' to guarantee optimality of a division between control law design and filtering of plant uncertainty. Peczkowski and Sain (1978) have solved a model matching problem using transfer functions. Taking into consideration this investigation, Peczkowski et al. (1979) proposed the Total Synthesis Problem (TSP), wherein both the command/output-response and command/control-response are to be synthesized, subject to the plant constraint. The TSP concept can be subdivided into a Nominal Design Problem (NDP), which is not dependent upon specific controller structures, and a Feedback Synthesis Problem (FSP), which is. Gejji (1980) found that NDP was characterized in terms of the plant structural matrices and a single, 'good' transfer function matrix. Sain et al. (1981) have extended this NDP work. The present investigation is concerned with a study of FSP for the unity feedback case. NDP, together with feedback synthesis, is understood as a Total Synthesis Problem.

  18. Application of Modified Flower Pollination Algorithm on Mechanical Engineering Design Problem

    Science.gov (United States)

    Kok Meng, Ong; Pauline, Ong; Chee Kiong, Sia; Wahab, Hanani Abdul; Jafferi, Noormaziah

    2017-01-01

    The aim of the optimization is to obtain the best solution among other solutions in order to achieve the objective of the problem without evaluation on all possible solutions. In this study, an improved flower pollination algorithm, namely, the Modified Flower Pollination Algorithms (MFPA) is developed. Comprising of the elements of chaos theory, frog leaping local search and adaptive inertia weight, the performance of MFPA is evaluated in optimizing five benchmark mechanical engineering design problems - tubular column design, speed reducer, gear train, tension/compression spring design and pressure vessel. The obtained results are listed and compared with the results of the other state-of-art algorithms. Assessment shows that the MFPA gives promising result in finding the optimal design for all considered mechanical engineering problems.

  19. Ergonomic (human factors) problems in design of NPPs. A review of TMI and Chernobyl accidents

    International Nuclear Information System (INIS)

    Huang Xiangrui; Zheng Fuyu; Gao Jia

    1994-01-01

    The general principle of ergonomic in design of NPPs is given and some causes of TMI and Chernobyl accidents from the view point of human factor engineering are reviewed. The paper also introduces some Ergonomic problems in design, operation and management of earlier NPPs. Some ergonomic principles of man-machine systems design have been described. Some proposals have been suggested for improving human reliability in NPPs

  20. Problems and their solutions in practical application of Eurocodes in seismic design of RC structures

    Directory of Open Access Journals (Sweden)

    Milev Jordan

    2016-01-01

    Full Text Available The main purpose of the paper is to present practical application of Eurocodes in the field of RC structures design. The selected examples represent the main problems in practical application of Eurocodes for seismic analysis and design of RC Structures in Bulgarian construction practice. The analysis is focused on some structural and economic problems as well as on some contradictions in Eurocode 8 itself. Special attention is paid to the practical solution of the following problems: recognition of torsionally flexible systems, stiffness reduction of RC elements for linear analysis dimensions and detailing of confined boundary areas of shear walls, detailing of wall structures, etc. Those problems appear during the practical design of some buildings in Bulgaria. Several proposals for solving some problems defined in the paper are presented through some practical examples. Some conclusions are made for further application of Eurocode 8 in the design and construction practice. The importance of some rules and procedures in Eurocode 8 is supported by the examples of damaged RC members during the past earthquakes. The problems of Eurocode 8 and their solutions are illustrated through the experience of Bulgarian construction practice.

  1. Solving Large Scale Nonlinear Eigenvalue Problem in Next-Generation Accelerator Design

    Energy Technology Data Exchange (ETDEWEB)

    Liao, Ben-Shan; Bai, Zhaojun; /UC, Davis; Lee, Lie-Quan; Ko, Kwok; /SLAC

    2006-09-28

    A number of numerical methods, including inverse iteration, method of successive linear problem and nonlinear Arnoldi algorithm, are studied in this paper to solve a large scale nonlinear eigenvalue problem arising from finite element analysis of resonant frequencies and external Q{sub e} values of a waveguide loaded cavity in the next-generation accelerator design. They present a nonlinear Rayleigh-Ritz iterative projection algorithm, NRRIT in short and demonstrate that it is the most promising approach for a model scale cavity design. The NRRIT algorithm is an extension of the nonlinear Arnoldi algorithm due to Voss. Computational challenges of solving such a nonlinear eigenvalue problem for a full scale cavity design are outlined.

  2. Dynamic Network Design Problem under Demand Uncertainty: An Adjustable Robust Optimization Approach

    Directory of Open Access Journals (Sweden)

    Hua Sun

    2014-01-01

    Full Text Available This paper develops an adjustable robust optimization approach for a network design problem explicitly incorporating traffic dynamics and demand uncertainty. In particular, a cell transmission model based network design problem of linear programming type is considered to describe dynamic traffic flows, and a polyhedral uncertainty set is used to characterize the demand uncertainty. The major contribution of this paper is to formulate such an adjustable robust network design problem as a tractable linear programming model and justify the model which is less conservative by comparing its solution performance with the robust solution from the usual robust model. The numerical results using one network from the literature demonstrate the modeling advantage of the adjustable robust optimization and provided strategic managerial insights for enacting capacity expansion policies under demand uncertainty.

  3. Rotamer optimization for protein design through MAP estimation and problem-size reduction.

    Science.gov (United States)

    Hong, Eun-Jong; Lippow, Shaun M; Tidor, Bruce; Lozano-Pérez, Tomás

    2009-09-01

    The search for the global minimum energy conformation (GMEC) of protein side chains is an important computational challenge in protein structure prediction and design. Using rotamer models, the problem is formulated as a NP-hard optimization problem. Dead-end elimination (DEE) methods combined with systematic A* search (DEE/A*) has proven useful, but may not be strong enough as we attempt to solve protein design problems where a large number of similar rotamers is eligible and the network of interactions between residues is dense. In this work, we present an exact solution method, named BroMAP (branch-and-bound rotamer optimization using MAP estimation), for such protein design problems. The design goal of BroMAP is to be able to expand smaller search trees than conventional branch-and-bound methods while performing only a moderate amount of computation in each node, thereby reducing the total running time. To achieve that, BroMAP attempts reduction of the problem size within each node through DEE and elimination by lower bounds from approximate maximum-a-posteriori (MAP) estimation. The lower bounds are also exploited in branching and subproblem selection for fast discovery of strong upper bounds. Our computational results show that BroMAP tends to be faster than DEE/A* for large protein design cases. BroMAP also solved cases that were not solved by DEE/A* within the maximum allowed time, and did not incur significant disadvantage for cases where DEE/A* performed well. Therefore, BroMAP is particularly applicable to large protein design problems where DEE/A* struggles and can also substitute for DEE/A* in general GMEC search. Copyright 2009 Wiley Periodicals, Inc.

  4. Optimization Techniques for Design Problems in Selected Areas in WSNs: A Tutorial.

    Science.gov (United States)

    Ibrahim, Ahmed; Alfa, Attahiru

    2017-08-01

    This paper is intended to serve as an overview of, and mostly a tutorial to illustrate, the optimization techniques used in several different key design aspects that have been considered in the literature of wireless sensor networks (WSNs). It targets the researchers who are new to the mathematical optimization tool, and wish to apply it to WSN design problems. We hence divide the paper into two main parts. One part is dedicated to introduce optimization theory and an overview on some of its techniques that could be helpful in design problem in WSNs. In the second part, we present a number of design aspects that we came across in the WSN literature in which mathematical optimization methods have been used in the design. For each design aspect, a key paper is selected, and for each we explain the formulation techniques and the solution methods implemented. We also provide in-depth analyses and assessments of the problem formulations, the corresponding solution techniques and experimental procedures in some of these papers. The analyses and assessments, which are provided in the form of comments, are meant to reflect the points that we believe should be taken into account when using optimization as a tool for design purposes.

  5. A path based model for a green liner shipping network design problem

    DEFF Research Database (Denmark)

    Jepsen, Mads Kehlet; Brouer, Berit Dangaard; Plum, Christian Edinger Munk

    2011-01-01

    a new path based MIP model for the Liner shipping Network Design Problem minimizing the cost of vessels and their fuel consumption facilitating a green network. The proposed model reduces problem size using a novel aggregation of demands. A decomposition method enabling delayed column generation......Liner shipping networks are the backbone of international trade providing low transportation cost, which is a major driver of globalization. These networks are under constant pressure to deliver capacity, cost effectiveness and environmentally conscious transport solutions. This article proposes...... is presented. The subproblems have similar structure to Vehicle Routing Problems, which can be solved using dynamic programming....

  6. A Benders decomposition-based Matheuristic for the Cardinality Constrained Shift Design Problem

    DEFF Research Database (Denmark)

    Lusby, Richard Martin; Larsen, Jesper; Range, Troels Martin

    The Shift Design Problem is an important optimization problem which arises when scheduling personnel in industries that require continuous operation. Based on the forecast, required staffing levels for a set of time periods, a set of shift types that best covers the demand must be determined...... the problem. Furthermore, we argue that an important step in this approach is finding dual alternative optimal solutions to the Benders subproblems and describe an approach to obtain a diverse set of these. Numerical tests show that the described methodology significantly outperforms a commercial Mixed...

  7. THE PROBLEM OF THE FEASIBILITY STUDY IN RESPECT OF DESIGN OF JOINTS OF METAL STRUCTURES

    Directory of Open Access Journals (Sweden)

    Morozova Dina Vol'demarovna

    2012-12-01

    It is noteworthy that this problem enjoyed much attention back in the past when the country suffered from steel deficit, and metal processing plants could not keep up with the needs of consumers. This problem was dealt with by Y.M. Lihtarnikov, a Soviet scientist, who published his work "Variant design and optimization of steel structures" in 1979. The authors employ the theoretical base developed by the scientist to perform their research into the optimum solutions to the problems of several types of metal joints.

  8. A Rule-Based Local Search Algorithm for General Shift Design Problems in Airport Ground Handling

    DEFF Research Database (Denmark)

    Clausen, Tommy

    We consider a generalized version of the shift design problem where shifts are created to cover a multiskilled demand and fit the parameters of the workforce. We present a collection of constraints and objectives for the generalized shift design problem. A local search solution framework with mul...... with multiple neighborhoods and a loosely coupled rule engine based on simulated annealing is presented. Computational experiments on real-life data from various airport ground handling organization show the performance and flexibility of the proposed algorithm....

  9. A Branch-and-Price Approach to the Feeder Network Design Problem

    DEFF Research Database (Denmark)

    Santini, Alberto; Plum, Christian Edinger Munk; Røpke, Stefan

    2017-01-01

    In this paper we consider the problem of designing a container liner shipping feeder network. The designer has to choose which port to serve during many rotations that start and end at a central hub. Many operational characteristics are considered, such as variable leg-by-leg speeds and cargo...... transit times. Realistic instances are generated from the LinerLib benchmark suite. The problem is solved with a branch-and-price algorithm, which can solve most instances to optimality within one hour. The results also provide insights on the cost structure and desirable features of optimal routes...

  10. A New Optimization Model for Computer-Aided Molecular Design Problems

    DEFF Research Database (Denmark)

    Zhang, Lei; Cignitti, Stefano; Gani, Rafiqul

    Computer-Aided Molecular Design (CAMD) is a method to design molecules with desired properties. That is, through CAMD, it is possible to generate molecules that match a specified set of target properties. CAMD has attracted much attention in recent years due to its ability to design novel as well...... with structure information considered due to the increased size of the mathematical problem and number of alternatives. Thus, decomposition-based approach is proposed to solve the problem. In this approach, only first-order groups are considered in the first step to obtain the building block of the designed...... molecule, then the property model is refined with second-order groups based on the results of the first step. However, this may result in the possibility of an optimal solution being excluded. Samudra and Sahinidis [4] used property relaxation method in the first step to avoid this situation...

  11. ∊-constraint heat transfer search (∊-HTS algorithm for solving multi-objective engineering design problems

    Directory of Open Access Journals (Sweden)

    Mohamed A. Tawhid

    2018-01-01

    Full Text Available In this paper, an effective ∊-constraint heat transfer search (∊-HTS algorithm for the multi-objective engineering design problems is presented. This algorithm is developed to solve multi-objective optimization problems by evaluating a set of single objective sub-problems. The effectiveness of the proposed algorithm is checked by implementing it on multi-objective benchmark problems that have various characteristics of Pareto front such as discrete, convex, and non-convex. This algorithm is also tested for several distinctive multi-objective engineering design problems, such as four bar truss problem, gear train problem, multi-plate disc brake design, speed reducer problem, welded beam design, and spring design problem. Moreover, the numerical experimentation shows that the proposed algorithm generates the solution to represent true Pareto front.

  12. Blahut-Arimoto algorithm and code design for action-dependent source coding problems

    DEFF Research Database (Denmark)

    Trillingsgaard, Kasper Fløe; Simeone, Osvaldo; Popovski, Petar

    2013-01-01

    for this problem is proposed. Moreover, a simplified two-stage code structure based on multiplexing is put forth, whereby the first stage encodes the actions and the second stage is composed of an array of classical Wyner-Ziv codes, one for each action. Leveraging this structure, specific coding....../decoding strategies are designed based on LDGM codes and message passing. Through numerical examples, the proposed code design is shown to achieve performance close to the rate-distortion-cost function....

  13. Invariant Manifolds, the Spatial Three-Body Problem and Space Mission Design

    Science.gov (United States)

    Gomez, G.; Koon, W. S.; Lo, Martin W.; Marsden, J. E.; Masdemont, J.; Ross, S. D.

    2001-01-01

    The invariant manifold structures of the collinear libration points for the spatial restricted three-body problem provide the framework for understanding complex dynamical phenomena from a geometric point of view. In particular, the stable and unstable invariant manifold 'tubes' associated to libration point orbits are the phase space structures that provide a conduit for orbits between primary bodies for separate three-body systems. These invariant manifold tubes can be used to construct new spacecraft trajectories, such as 'Petit Grand Tour' of the moons of Jupiter. Previous work focused on the planar circular restricted three-body problem. The current work extends the results to the spatial case.

  14. On well-partial-order theory and its application to combinatorial problems of VLSI design

    Science.gov (United States)

    Fellows, M.; Langston, M.

    1990-01-01

    We nonconstructively prove the existence of decision algorithms with low-degree polynomial running times for a number of well-studied graph layout, placement, and routing problems. Some were not previously known to be in p at all; others were only known to be in p by way of brute force or dynamic programming formulations with unboundedly high-degree polynomial running times. Our methods include the application of the recent Robertson-Seymour theorems on the well-partial-ordering of graphs under both the minor and immersion orders. We also briefly address the complexity of search versions of these problems.

  15. IT Project Portfolio Management: Vertical and Horizontal Work Design Problems in a Public Organization

    DEFF Research Database (Denmark)

    Hansen, Lars Kristian

    2013-01-01

    arbejder på at forbedre dens IT PPM praksisser. Undersøgelsen anvender Work Design Teori til at analysere kommunens IT PPM praksisser på tværs af hierarkiske niveauer og organisatoriske enheder i bestræbelsen på, at besvare følgende tre forskningsspørgsmål:(1) Hvordan udfører en offentlig organisation...... and Van De Ven’s (2005) Work Design Teori, der sondrer mellem vertikal- og horisontal arbejdsdeling. Vertikal deling af arbejde bliver betragtet som fordelingen af autoritet, viden og resurser, hvilket undersøgelsen finder værende delt ud på fire hierarkiske niveauer: (1) det politiske niveau med den...... af det andet forskningsspørgsmål anvendes Work Design Teori til at identificere problemer indenfor tre relaterede problemområder: hierarkiske dekompositions problemer, modularitets problemer og komplekse netværks problemer. De identificerede problemer er sammenfattet i en model bestående af 14...

  16. Systematic network synthesis and design: Problem formulation, superstructure generation, data management and solution

    DEFF Research Database (Denmark)

    Quaglia, Alberto; Gargalo, Carina L.; Chairakwongsa, Siwanat

    2015-01-01

    is still limited by the complexity associated with the mathematical formulation of some problems. In particular, the tasks of design space definition and representation as superstructure, as well as the data collection, validation and handling may become too complex and cumbersome to execute, especially...

  17. The Design of a Mathematics Problem Using Real-Life Context for Young Children

    Science.gov (United States)

    Cheng, Lu Pien

    2013-01-01

    In this paper the teachers' learning journey on designing a mathematics problem that involves a real-life context is reported. This is part of a larger project undertaken in a primary school in Singapore where the teachers were engaged in planning, observing and critiquing mathematics lessons to investigate teaching and learning. These unique…

  18. Performance of a genetic algorithm for solving the multi-objective, multimodel transportation network design problem

    NARCIS (Netherlands)

    Brands, Ties; van Berkum, Eric C.

    2014-01-01

    The optimization of infrastructure planning in a multimodal network is defined as a multi-objective network design problem, with accessibility, use of urban space by parking, operating deficit and climate impact as objectives. Decision variables are the location of park and ride facilities, train

  19. Effectiveness of a programme design for the development of competence in solving clinical problems

    NARCIS (Netherlands)

    Ramaekers, Stephan|info:eu-repo/dai/nl/304827630; Van Keulen, Hanno; Van Beukelen, Peter; Kremer, Wim|info:eu-repo/dai/nl/073488062; Pilot, Albert|info:eu-repo/dai/nl/068350880

    2012-01-01

    BACKGROUND: To apply what has been learned theoretically in a clinical context is for many students a major challenge. In order to ease their transition into practice, a training programme was developed, focusing on learning to solve clinical problems. AIMS: The programme is designed for veterinary

  20. Integrating Blended and Problem-Based Learning into an Architectural Housing Design Studio: A Case Study

    Science.gov (United States)

    Bregger, Yasemin Alkiser

    2017-01-01

    This paper presents how a blended learning pedagogic model is integrated into an architectural design studio by adapting the problem-based learning process and housing issues in Istanbul Technical University (ITU), during fall 2015 and spring 2016 semesters for fourth and sixth level students. These studios collaborated with the "Introduction…

  1. Case Designs for Ill-Structured Problems: Analysis and Implications for Practice

    Science.gov (United States)

    Dabbagh, Nada; Blijd, Cecily Williams

    2009-01-01

    This study is a third in a series of studies that examined students' information seeking and problem solving behaviors while interacting with one of two types of web-based representations of an ill-structured instructional design case: hierarchical (tree-like) and heterarchical (network-like). A Java program was used to track students' hypermedia…

  2. A Review of Knowledge Based Problem Solving as a Basis for a Genetics Experiment Designing System.

    Science.gov (United States)

    1977-03-01

    knowledge base. [Section IV.3.3.LI] 17. Ru l e acquisition has usea the problem solving context as well as a rule model to guide the acquisition of a 4...the design process continues , for example , cutting may become an exonuclease or separation may become electrophoresis . It is not too surprising that

  3. A Note on the Art of Network Design Problems | Osagiede | Journal ...

    African Journals Online (AJOL)

    In this study, we describe some Network Design Problems (NDPs) as well as the network flowbased improvement algorithm for neighbourhood search defined by cycles. The main part of the study is structured around the formulation of the expected duration of stay in the educational system as a NDP. The fundamental ...

  4. A Further Study of Productive Failure in Mathematical Problem Solving: Unpacking the Design Components

    Science.gov (United States)

    Kapur, Manu

    2011-01-01

    This paper replicates and extends my earlier work on productive failure in mathematical problem solving (Kapur, doi:10.1007/s11251-009-9093-x, 2009). One hundred and nine, seventh-grade mathematics students taught by the same teacher from a Singapore school experienced one of three learning designs: (a) traditional lecture and practice (LP), (b)…

  5. Designing Online Marketplace To Resolve Marketing Problem For Small and Medium Enterprises (SMEs

    Directory of Open Access Journals (Sweden)

    Aditya Hermawan

    2017-03-01

    Full Text Available The study aims to design an online marketplace to provide solutions to problems faced by Small and Medium Enterprises (SMEs, the difficulty to market their products online. One of the problems faced by SMEs is difficult to market their products online. One of the solutions that we provide is by designing an online marketplace to solve marketing problems effectively. We found that SMEs have attempted to market their products through social media such as facebook, twitter and others. In addition, some SMEs also have a website and advertise their products through online advertising. However, many of those who did not know how to market products online in order to increase sales. We designed an online marketplace for SMEs based on the concept of e-commerce to resolve the problems faced by SMEs, the effective marketing. The online market design is made taking into account the needs of SMEs as well as customer needs. Therefore, this study was conducted to SMEs in Malang, East Java, Indonesia  and the people who often make purchases online.With the existence of the online market, SMEs can increase sales lead to increased profits for SMEs. Keyword: Online market, E-Commerce, Maketing

  6. Design and Facilitation of Problem-Based Learning in Graduate Teacher Education: An MA TESOL Case

    Science.gov (United States)

    Caswell, Cynthia Ann

    2016-01-01

    This exploratory, evaluative case study introduces a new context for problem-based learning (PBL) involving an iterative, modular approach to curriculum-wide delivery of PBL in an MA TESOL program. The introduction to the curriculum context provides an overview of the design and delivery features particular to the situation. The delivery approach…

  7. PREVIOUS SECOND TRIMESTER ABORTION

    African Journals Online (AJOL)

    PNLC

    PREVIOUS SECOND TRIMESTER ABORTION: A risk factor for third trimester uterine rupture in three ... for accurate diagnosis of uterine rupture. KEY WORDS: Induced second trimester abortion - Previous uterine surgery - Uterine rupture. ..... scarred uterus during second trimester misoprostol- induced labour for a missed ...

  8. Global optimization of discrete truss topology design problems using a parallel cut-and-branch method

    DEFF Research Database (Denmark)

    Rasmussen, Marie-Louise Højlund; Stolpe, Mathias

    2008-01-01

    The subject of this article is solving discrete truss topology optimization problems with local stress and displacement constraints to global optimum. We consider a formulation based on the Simultaneous ANalysis and Design (SAND) approach. This intrinsically non-convex problem is reformulated...... to a mixed-integer linear program, which is solved with a parallel implementation of branch-and-bound. Additional valid inequalities and cuts are introduced to give a stronger representation of the problem, which improves convergence and speed up of the parallel method. The valid inequalities represent...... the physics, and the cuts (Combinatorial Benders’ and projected Chvátal–Gomory) come from an understanding of the particular mathematical structure of the reformulation. The impact of a stronger representation is investigated on several truss topology optimization problems in two and three dimensions....

  9. Conceptual design of semi-automatic wheelbarrow to overcome ergonomics problems among palm oil plantation workers

    Science.gov (United States)

    Nawik, N. S. M.; Deros, B. M.; Rahman, M. N. A.; Sukadarin, E. H.; Nordin, N.; Tamrin, S. B. M.; Bakar, S. A.; Norzan, M. L.

    2015-12-01

    An ergonomics problem is one of the main issues faced by palm oil plantation workers especially during harvesting and collecting of fresh fruit bunches (FFB). Intensive manual handling and labor activities involved have been associated with high prevalence of musculoskeletal disorders (MSDs) among palm oil plantation workers. New and safe technology on machines and equipment in palm oil plantation are very important in order to help workers reduce risks and injuries while working. The aim of this research is to improve the design of a wheelbarrow, which is suitable for workers and a small size oil palm plantation. The wheelbarrow design was drawn using CATIA ergonomic features. The characteristic of ergonomics assessment is performed by comparing the existing design of wheelbarrow. Conceptual design was developed based on the problems that have been reported by workers. From the analysis of the problem, finally have resulting concept design the ergonomic quality of semi-automatic wheelbarrow with safe and suitable used for palm oil plantation workers.

  10. A Genetic Algorithm for Selection of Fixed-Size Subsets with Application to Design Problems

    Directory of Open Access Journals (Sweden)

    Mark A. Wolters

    2015-11-01

    Full Text Available The R function kofnGA conducts a genetic algorithm search for the best subset of k items from a set of n alternatives, given an objective function that measures the quality of a subset. The function fills a gap in the presently available subset selection software, which typically searches over a range of subset sizes, restricts the types of objective functions considered, or does not include freely available code. The new function is demonstrated on two types of problem where a fixed-size subset search is desirable: design of environmental monitoring networks, and D-optimal design of experiments. Additionally, the performance is evaluated on a class of constructed test problems with a novel design that is interesting in its own right.

  11. Estudios previos cursados y género de los maestros de primaria en formación: efectos sobre la resolución de problemas / Pre-service primary teachers' gender and studies previously undertaken: effects on problem solving

    Directory of Open Access Journals (Sweden)

    Alexandre Caballer Alonso

    2014-10-01

    Full Text Available Resumen: Este trabajo analiza la influencia del género y los estudios previos cursados en la resolución de problemas. Se utilizó un diseño experimental con dos variables independientes (género y estudios previos y una variable dependiente (puntuación en los problemas. Se administró un cuadernillo con dos problemas de diferente estructura a 66 estudiantes de tercer curso del Grado de Maestro en Educacion Primaria de la misma Facultad (Facultad de Magisterio de la Universidad de Valencia, España. Los resultados de los análisis de varianza simple muestran que: a los estudiantes de sexo masculino resuelven el problema difícil con más éxito que las estudiantes, b los estudiantes que han cursado bachillerato no resuelven los problemas significativamente mejor que los que no lo han cursado y, c los estudiantes que siguieron un itinerario en 4º de la ESO con Física y Química resuelven significativamente mejor los problemas que los restantes. Abstract: This study analyses the influence of gender and studies previously undertaken on problem-solving. An experimental design was used with two independent variables (gender and studies previously undertaken and one dependent variable (scores in the problems. A booklet containing two word problems that differ from each other in structure was administered to 66 third-year pre-service primary teachers from the same Faculty (Faculty of Teacher Training, University of Valencia, Spain. The results of the analyses of variance simple showed that: a men undergraduate students solve the difficult problem more successfully than women undergraduate students, b students who had completed post-compulsory secondary education do not solve the problems significantly better than the others, and c students who had studied physics and chemistry in the tenth grade at high school solve the problems significantly better than the others.

  12. Designing training programs for the development of emotional intelligence in adolescents with behavioral problems

    Directory of Open Access Journals (Sweden)

    A.V. Degtyarev

    2013-10-01

    Full Text Available In this article, deviant behavior is considered as a combination of different manifestations of personality, leading eventually to its social desaptation. It is shown that an effective method of preventing deviant behavior is psychological training. Group training activity helps to solve the problems associated with the development of various behavioral skills, to provide psychological support, and can be used as a means of psychological work with teenagers with behavioral problems. We discuss the basic points required to effectively create and conduct training programs in general, as well as the challenges and opportunities of designing trainings in order to develop emotional intelligence as a method of prevention of deviant behavior

  13. Inverse problems in complex material design: Applications to non-crystalline solids

    Science.gov (United States)

    Biswas, Parthapratim; Drabold, David; Elliott, Stephen

    The design of complex amorphous materials is one of the fundamental problems in disordered condensed-matter science. While impressive developments of ab-initio simulation methods during the past several decades have brought tremendous success in understanding materials property from micro- to mesoscopic length scales, a major drawback is that they fail to incorporate existing knowledge of the materials in simulation methodologies. Since an essential feature of materials design is the synergy between experiment and theory, a properly developed approach to design materials should be able to exploit all available knowledge of the materials from measured experimental data. In this talk, we will address the design of complex disordered materials as an inverse problem involving experimental data and available empirical information. We show that the problem can be posed as a multi-objective non-convex optimization program, which can be addressed using a number of recently-developed bio-inspired global optimization techniques. In particular, we will discuss how a population-based stochastic search procedure can be used to determine the structure of non-crystalline solids (e.g. a-SiH, a-SiO2, amorphous graphene, and Fe and Ni clusters). The work is partially supported by NSF under Grant Nos. DMR 1507166 and 1507670.

  14. Analysing task design and students' responses to context-based problems through different analytical frameworks

    Science.gov (United States)

    Broman, Karolina; Bernholt, Sascha; Parchmann, Ilka

    2015-05-01

    Background:Context-based learning approaches are used to enhance students' interest in, and knowledge about, science. According to different empirical studies, students' interest is improved by applying these more non-conventional approaches, while effects on learning outcomes are less coherent. Hence, further insights are needed into the structure of context-based problems in comparison to traditional problems, and into students' problem-solving strategies. Therefore, a suitable framework is necessary, both for the analysis of tasks and strategies. Purpose:The aim of this paper is to explore traditional and context-based tasks as well as students' responses to exemplary tasks to identify a suitable framework for future design and analyses of context-based problems. The paper discusses different established frameworks and applies the Higher-Order Cognitive Skills/Lower-Order Cognitive Skills (HOCS/LOCS) taxonomy and the Model of Hierarchical Complexity in Chemistry (MHC-C) to analyse traditional tasks and students' responses. Sample:Upper secondary students (n=236) at the Natural Science Programme, i.e. possible future scientists, are investigated to explore learning outcomes when they solve chemistry tasks, both more conventional as well as context-based chemistry problems. Design and methods:A typical chemistry examination test has been analysed, first the test items in themselves (n=36), and thereafter 236 students' responses to one representative context-based problem. Content analysis using HOCS/LOCS and MHC-C frameworks has been applied to analyse both quantitative and qualitative data, allowing us to describe different problem-solving strategies. Results:The empirical results show that both frameworks are suitable to identify students' strategies, mainly focusing on recall of memorized facts when solving chemistry test items. Almost all test items were also assessing lower order thinking. The combination of frameworks with the chemistry syllabus has been

  15. Design and evaluation of a robust dynamic neurocontroller for a multivariable aircraft control problem

    Science.gov (United States)

    Troudet, T.; Garg, S.; Merrill, W.

    1992-01-01

    The design of a dynamic neurocontroller with good robustness properties is presented for a multivariable aircraft control problem. The internal dynamics of the neurocontroller are synthesized by a state estimator feedback loop. The neurocontrol is generated by a multilayer feedforward neural network which is trained through backpropagation to minimize an objective function that is a weighted sum of tracking errors, and control input commands and rates. The neurocontroller exhibits good robustness through stability margins in phase and vehicle output gains. By maintaining performance and stability in the presence of sensor failures in the error loops, the structure of the neurocontroller is also consistent with the classical approach of flight control design.

  16. California residential energy standards: problems and recommendations relating to implementation, enforcement, and design. [Thermal insulation

    Energy Technology Data Exchange (ETDEWEB)

    1977-08-01

    Documents relevant to the development and implementation of the California energy insulation standards for new residential buildings were evaluated and a survey was conducted to determine problems encountered in the implementation, enforcement, and design aspects of the standards. The impact of the standards on enforcement agencies, designers, builders and developers, manufacturers and suppliers, consumers, and the building process in general is summarized. The impact on construction costs and energy savings varies considerably because of the wide variation in prior insulation practices and climatic conditions in California. The report concludes with a series of recommendations covering all levels of government and the building process. (MCW)

  17. Seven-step problem-based learning in an interaction design course

    DEFF Research Database (Denmark)

    Schultz, Nette; Christensen, Hans Peter

    2004-01-01

    design process. These two processes share many characteristics, and the most prominent are: How to explore, analyze and define the problem space, the importance of team-work and -development and finally creativity to design and find a solution. We have experimented with additional short mandatory...... others in a single course. The evaluation results showed that the students definitely took a deep approach to learning, and indicated clearly that the students had obtained competences not only within the traditional HCI curriculum but also in terms of team-work skills....

  18. Experiencing a Problem-Based Learning Approach for Teaching Reconfigurable Architecture Design

    Directory of Open Access Journals (Sweden)

    Erwan Fabiani

    2009-01-01

    Full Text Available This paper presents the “reconfigurable computing” teaching part of a computer science master course (first year on parallel architectures. The practical work sessions of this course rely on active pedagogy using problem-based learning, focused on designing a reconfigurable architecture for the implementation of an application class of image processing algorithms. We show how the successive steps of this project permit the student to experiment with several fundamental concepts of reconfigurable computing at different levels. Specific experiments include exploitation of architectural parallelism, dataflow and communicating component-based design, and configurability-specificity tradeoffs.

  19. Underwater fuel handling equipment maintenance. Verification of design assumptions, specific problems and tools, case study

    International Nuclear Information System (INIS)

    Kurek, J.B.

    1995-01-01

    The majority of CANDU Fuel Transfer System equipment at Pickering is located under fourteen feet of water, as dictated by the containment and shielding requirements. Such arrangement, however, creates specific problems with equipment maintenance. Each single piece of equipment serves two generating units, which means in case of defect- double losses on production, or two units shut down simultaneously for planned maintenance. The requirement for underwater maintenance was not anticipated at the design stage, which multiples the level of difficulty, and creates requirement for developing special tools for each work. Removal of the damaged fuel from the receiving bays and decontamination of submerged equipment is also part of the problem. The purpose of this presentation is to share our experience with the designers, operators, maintenance mechanics and technical personnel of the other CANDU generating stations

  20. Multi-objective genetic algorithm for solving N-version program design problem

    International Nuclear Information System (INIS)

    Yamachi, Hidemi; Tsujimura, Yasuhiro; Kambayashi, Yasushi; Yamamoto, Hisashi

    2006-01-01

    N-version programming (NVP) is a programming approach for constructing fault tolerant software systems. Generally, an optimization model utilized in NVP selects the optimal set of versions for each module to maximize the system reliability and to constrain the total cost to remain within a given budget. In such a model, while the number of versions included in the obtained solution is generally reduced, the budget restriction may be so rigid that it may fail to find the optimal solution. In order to ameliorate this problem, this paper proposes a novel bi-objective optimization model that maximizes the system reliability and minimizes the system total cost for designing N-version software systems. When solving multi-objective optimization problem, it is crucial to find Pareto solutions. It is, however, not easy to obtain them. In this paper, we propose a novel bi-objective optimization model that obtains many Pareto solutions efficiently. We formulate the optimal design problem of NVP as a bi-objective 0-1 nonlinear integer programming problem. In order to overcome this problem, we propose a Multi-objective genetic algorithm (MOGA), which is a powerful, though time-consuming, method to solve multi-objective optimization problems. When implementing genetic algorithm (GA), the use of an appropriate genetic representation scheme is one of the most important issues to obtain good performance. We employ random-key representation in our MOGA to find many Pareto solutions spaced as evenly as possible along the Pareto frontier. To pursue improve further performance, we introduce elitism, the Pareto-insertion and the Pareto-deletion operations based on distance between Pareto solutions in the selection process. The proposed MOGA obtains many Pareto solutions along the Pareto frontier evenly. The user of the MOGA can select the best compromise solution among the candidates by controlling the balance between the system reliability and the total cost

  1. The constraints satisfaction problem approach in the design of an architectural functional layout

    Science.gov (United States)

    Zawidzki, Machi; Tateyama, Kazuyoshi; Nishikawa, Ikuko

    2011-09-01

    A design support system with a new strategy for finding the optimal functional configurations of rooms for architectural layouts is presented. A set of configurations satisfying given constraints is generated and ranked according to multiple objectives. The method can be applied to problems in architectural practice, urban or graphic design-wherever allocation of related geometrical elements of known shape is optimized. Although the methodology is shown using simplified examples-a single story residential building with two apartments each having two rooms-the results resemble realistic functional layouts. One example of a practical size problem of a layout of three apartments with a total of 20 rooms is demonstrated, where the generated solution can be used as a base for a realistic architectural blueprint. The discretization of design space is discussed, followed by application of a backtrack search algorithm used for generating a set of potentially 'good' room configurations. Next the solutions are classified by a machine learning method (FFN) as 'proper' or 'improper' according to the internal communication criteria. Examples of interactive ranking of the 'proper' configurations according to multiple criteria and choosing 'the best' ones are presented. The proposed framework is general and universal-the criteria, parameters and weights can be individually defined by a user and the search algorithm can be adjusted to a specific problem.

  2. Optimizing Supply Chain Collaboration Based on Agreement Buyer-Supplier Relationship with Network Design Problem

    Directory of Open Access Journals (Sweden)

    Wahyudi Sutopo

    2016-12-01

    Full Text Available In recent years, the rising competitive environment with shorter product life cycles and high customization forces industries to increase their flexibility, speed up their response, and enhance concurrent engineering designs. To integrate these prospects, supply chain collaboration becomes a pertinent strategy for industries to strengthen their competitiveness. The network design problem is used to implement supply chain collaboration. In the buying and selling process, sharing information between buyer and supplier are important to obtain a transaction decision. The optimimum supply chain profit can be identified by mathematical model of network design problem. The Mathematical Model takes into consideration the uncertainity in negotiation of supply chain, transportation problems, and locationallocation of products from supplier to buyer in the planning based on the time value of money. The results show that the model can be used to optimize the supply chain profit. The supplier gets a profit because income were received in the initial contract, while the buyer profit comes from lower pay.

  3. How scientific experiments are designed: Problem solving in a knowledge-rich, error-rich environment

    Science.gov (United States)

    Baker, Lisa M.

    While theory formation and the relation between theory and data has been investigated in many studies of scientific reasoning, researchers have focused less attention on reasoning about experimental design, even though the experimental design process makes up a large part of real-world scientists' reasoning. The goal of this thesis was to provide a cognitive account of the scientific experimental design process by analyzing experimental design as problem-solving behavior (Newell & Simon, 1972). Three specific issues were addressed: the effect of potential error on experimental design strategies, the role of prior knowledge in experimental design, and the effect of characteristics of the space of alternate hypotheses on alternate hypothesis testing. A two-pronged in vivo/in vitro research methodology was employed, in which transcripts of real-world scientific laboratory meetings were analyzed as well as undergraduate science and non-science majors' design of biology experiments in the psychology laboratory. It was found that scientists use a specific strategy to deal with the possibility of error in experimental findings: they include "known" control conditions in their experimental designs both to determine whether error is occurring and to identify sources of error. The known controls strategy had not been reported in earlier studies with science-like tasks, in which participants' responses to error had consisted of replicating experiments and discounting results. With respect to prior knowledge: scientists and undergraduate students drew on several types of knowledge when designing experiments, including theoretical knowledge, domain-specific knowledge of experimental techniques, and domain-general knowledge of experimental design strategies. Finally, undergraduate science students generated and tested alternates to their favored hypotheses when the space of alternate hypotheses was constrained and searchable. This result may help explain findings of confirmation

  4. Laparoscopy After Previous Laparotomy

    Directory of Open Access Journals (Sweden)

    Zulfo Godinjak

    2006-11-01

    Full Text Available Following the abdominal surgery, extensive adhesions often occur and they can cause difficulties during laparoscopic operations. However, previous laparotomy is not considered to be a contraindication for laparoscopy. The aim of this study is to present that an insertion of Veres needle in the region of umbilicus is a safe method for creating a pneumoperitoneum for laparoscopic operations after previous laparotomy. In the last three years, we have performed 144 laparoscopic operations in patients that previously underwent one or two laparotomies. Pathology of digestive system, genital organs, Cesarean Section or abdominal war injuries were the most common causes of previouslaparotomy. During those operations or during entering into abdominal cavity we have not experienced any complications, while in 7 patients we performed conversion to laparotomy following the diagnostic laparoscopy. In all patients an insertion of Veres needle and trocar insertion in the umbilical region was performed, namely a technique of closed laparoscopy. Not even in one patient adhesions in the region of umbilicus were found, and no abdominal organs were injured.

  5. Workflow Agents vs. Expert Systems: Problem Solving Methods in Work Systems Design

    Science.gov (United States)

    Clancey, William J.; Sierhuis, Maarten; Seah, Chin

    2009-01-01

    During the 1980s, a community of artificial intelligence researchers became interested in formalizing problem solving methods as part of an effort called "second generation expert systems" (2nd GES). How do the motivations and results of this research relate to building tools for the workplace today? We provide an historical review of how the theory of expertise has developed, a progress report on a tool for designing and implementing model-based automation (Brahms), and a concrete example how we apply 2nd GES concepts today in an agent-based system for space flight operations (OCAMS). Brahms incorporates an ontology for modeling work practices, what people are doing in the course of a day, characterized as "activities." OCAMS was developed using a simulation-to-implementation methodology, in which a prototype tool was embedded in a simulation of future work practices. OCAMS uses model-based methods to interactively plan its actions and keep track of the work to be done. The problem solving methods of practice are interactive, employing reasoning for and through action in the real world. Analogously, it is as if a medical expert system were charged not just with interpreting culture results, but actually interacting with a patient. Our perspective shifts from building a "problem solving" (expert) system to building an actor in the world. The reusable components in work system designs include entire "problem solvers" (e.g., a planning subsystem), interoperability frameworks, and workflow agents that use and revise models dynamically in a network of people and tools. Consequently, the research focus shifts so "problem solving methods" include ways of knowing that models do not fit the world, and ways of interacting with other agents and people to gain or verify information and (ultimately) adapt rules and procedures to resolve problematic situations.

  6. Wicked ID: Conceptual Framework for Considering Instructional Design as a Wicked Problem

    Directory of Open Access Journals (Sweden)

    Katrin Becker

    2007-02-01

    Full Text Available The process of instructional design has parallels in other design disciplines. Software design is one that has experienced intense attention in the last 30 or so years, and many lessons learned there can be applied to ID. Using software design as a springboard, this concept paper seeks to propose a new approach to ID. It suggests that instructional design is almost always a Wicked Problem. The connection is formed between Wicked Problems as first described by Rittel and Webber in 1973, and the models in and processes of instructional design. The areas of social planning, organizational management and software design all posses some accepted and tested approaches to the solution of Wicked Problems. These will be described, and how they can be applied to ID will be explained. Finally, this paper will propose a meta-model for ID and explain how it can be used in the current context. Résumé : Le processus de conception pédagogique a des similitudes avec d’autres disciplines. La conception de logiciels a fait l’objet d’une grande attention dans les trente dernières années et de nombreuses leçons tirées peuvent s’appliquer à la conception pédagogique. En se basant sur la conception de logiciels, cet article cherche à proposer une nouvelle méthode à la conception pédagogique. Il laisse entendre que la conception pédagogique constitue presque toujours un problème épineux. Le lien est formé entre les problèmes épineux tels que décrits par Rittel et Webber en 1973 et les modèles et processus de la conception pédagogique. Les secteurs de l’organisation sociale, de la gestion des organisations et de la conception de logiciels comptent des méthodes acceptées et validées à la résolution de problèmes épineux. Nous les décrirons et expliquerons comment ils peuvent servir à la conception pédagogique. Enfin, l’article proposera un meta-modèle de la conception pédagogique et expliquera comment il peut servir dans le

  7. Common statistical and research design problems in manuscripts submitted to high-impact medical journals

    Directory of Open Access Journals (Sweden)

    Harris Alex HS

    2011-08-01

    Full Text Available Abstract Background To assist educators and researchers in improving the quality of medical research, we surveyed the editors and statistical reviewers of high-impact medical journals to ascertain the most frequent and critical statistical errors in submitted manuscripts. Findings The Editors-in-Chief and statistical reviewers of the 38 medical journals with the highest impact factor in the 2007 Science Journal Citation Report and the 2007 Social Science Journal Citation Report were invited to complete an online survey about the statistical and design problems they most frequently found in manuscripts. Content analysis of the responses identified major issues. Editors and statistical reviewers (n = 25 from 20 journals responded. Respondents described problems that we classified into two, broad themes: A. statistical and sampling issues and B. inadequate reporting clarity or completeness. Problems included in the first theme were (1 inappropriate or incomplete analysis, including violations of model assumptions and analysis errors, (2 uninformed use of propensity scores, (3 failing to account for clustering in data analysis, (4 improperly addressing missing data, and (5 power/sample size concerns. Issues subsumed under the second theme were (1 Inadequate description of the methods and analysis and (2 Misstatement of results, including undue emphasis on p-values and incorrect inferences and interpretations. Conclusions The scientific quality of submitted manuscripts would increase if researchers addressed these common design, analytical, and reporting issues. Improving the application and presentation of quantitative methods in scholarly manuscripts is essential to advancing medical research.

  8. Searching for Authentic Context in Designing PISA-like Mathematics Problem: From Indoor to Outdoor Field Experience

    Science.gov (United States)

    Siswono, T. Y. E.; Kohar, A. W.; Rosyidi, A. H.; Hartono, S.; Masriyah

    2018-01-01

    Designing problem like in PISA is known as a challenging activity for teachers particularly as the use of authentic context within that type of problem. This paper aims to describe the experiences of secondary mathematics teachers in designing PISA-like problems within an innovative training program focusing on building teachers’ understanding on the concept of mathematical literacy. The teachers were engaged in a set of problem-solving and problem-posing activities using PISA-based problem within indoor and outdoor field experiences. Within indoor field experience, the teachers worked collaboratively in groups on designing PISA-like problems with a given context through problem generation and reformulation techniques. Within outdoor field experience, they worked on designing PISA-like problems with self-chosen context from the place where the outdoor field experience took place. Our analysis indicates that there were improvements on the PISA-like problems designed by teachers based on its level use of context from indoor to outdoor experience. Also, the teachers were relatively successful with creating appropriate and motivating contexts by harnessing a variety of context consisting of personal, occupational, societal, and scientific contexts. However, they still experienced difficulties in turning these contexts into an appropriate problem satisfying PISA framework such as regarding authenticity of context use, language structure, and PISA task profile.

  9. Informing a Pedagogy for Design and Problem-Solving in Hard Materials by Theorising Technologists' Learning Experiences

    Science.gov (United States)

    Potter, Patricia; France, Bev

    2018-01-01

    Design and problem solving are central to technology and have distinguished learning in technology from other curriculum areas. This research investigated how expert technologists learn design and problem solving through experience. Data was collected from four expert technologists and this information was analysed using learning theories that…

  10. Practical solutions for multi-objective optimization: An application to system reliability design problems

    International Nuclear Information System (INIS)

    Taboada, Heidi A.; Baheranwala, Fatema; Coit, David W.; Wattanapongsakorn, Naruemon

    2007-01-01

    For multiple-objective optimization problems, a common solution methodology is to determine a Pareto optimal set. Unfortunately, these sets are often large and can become difficult to comprehend and consider. Two methods are presented as practical approaches to reduce the size of the Pareto optimal set for multiple-objective system reliability design problems. The first method is a pseudo-ranking scheme that helps the decision maker select solutions that reflect his/her objective function priorities. In the second approach, we used data mining clustering techniques to group the data by using the k-means algorithm to find clusters of similar solutions. This provides the decision maker with just k general solutions to choose from. With this second method, from the clustered Pareto optimal set, we attempted to find solutions which are likely to be more relevant to the decision maker. These are solutions where a small improvement in one objective would lead to a large deterioration in at least one other objective. To demonstrate how these methods work, the well-known redundancy allocation problem was solved as a multiple objective problem by using the NSGA genetic algorithm to initially find the Pareto optimal solutions, and then, the two proposed methods are applied to prune the Pareto set

  11. A Location-Inventory-Routing Problem in Forward and Reverse Logistics Network Design

    Directory of Open Access Journals (Sweden)

    Qunli Yuchi

    2016-01-01

    Full Text Available We study a new problem of location-inventory-routing in forward and reverse logistic (LIRP-FRL network design, which simultaneously integrates the location decisions of distribution centers (DCs, the inventory policies of opened DCs, and the vehicle routing decision in serving customers, in which new goods are produced and damaged goods are repaired by a manufacturer and then returned to the market to satisfy customers’ demands as new ones. Our objective is to minimize the total costs of manufacturing and remanufacturing goods, building DCs, shipping goods (new or recovered between the manufacturer and opened DCs, and distributing new or recovered goods to customers and ordering and storage costs of goods. A nonlinear integer programming model is proposed to formulate the LIRP-FRL. A new tabu search (NTS algorithm is developed to achieve near optimal solution of the problem. Numerical experiments on the benchmark instances of a simplified version of the LIRP-FRL, the capacitated location routing problem, and the randomly generated LIRP-FRL instances demonstrate the effectiveness and efficiency of the proposed NTS algorithm in problem resolution.

  12. Optimal experimental design for nonlinear ill-posed problems applied to gravity dams

    Science.gov (United States)

    Lahmer, Tom

    2011-12-01

    The safe operation of gravity dams requires continuous monitoring in order to detect any changes concerning the stability of these constructions. Damage which may result from cyclic loading, variation in temperature, aging, chemical reactions, etc needs to be identified as fast and as reliable as possible. Generally, existing dams are well monitored by several types of measurement devices which log different physical quantities. The monitoring practice is according to official guidelines and the engineer’s experience. The aim of this paper is to perform a simulation-based optimal design for the monitoring of existing dams. Therefore, a design criterion which is based on average mean-squared reconstruction errors is derived. The reconstructions are obtained as regularized solutions of the nonlinear, inverse and ill-posed problem of damage identification. The basis for these investigations is a hydro-mechanically coupled model applied to gravity dams. Damaged zones in the dams are described by a smeared crack model, i.e. by spatially varying material properties. The inherent correlation of changes in the dominating parameters is explicitly considered during the inverse analysis. For the solution and regularization of the inverse problem, the iteratively regularized Gauss-Newton method is applied. Numerical results of the inverse analysis and the design process allow assessments of the applicability of the strategies proposed here.

  13. The Bilevel Design Problem for Communication Networks on Trains: Model, Algorithm, and Verification

    Directory of Open Access Journals (Sweden)

    Yin Tian

    2014-01-01

    Full Text Available This paper proposes a novel method to solve the problem of train communication network design. Firstly, we put forward a general description of such problem. Then, taking advantage of the bilevel programming theory, we created the cost-reliability-delay model (CRD model that consisted of two parts: the physical topology part aimed at obtaining the networks with the maximum reliability under constrained cost, while the logical topology part focused on the communication paths yielding minimum delay based on the physical topology delivered from upper level. We also suggested a method to solve the CRD model, which combined the genetic algorithm and the Floyd-Warshall algorithm. Finally, we used a practical example to verify the accuracy and the effectiveness of the CRD model and further applied the novel method on a train with six carriages.

  14. A Design-Adaptive Local Polynomial Estimator for the Errors-in-Variables Problem

    KAUST Repository

    Delaigle, Aurore

    2009-03-01

    Local polynomial estimators are popular techniques for nonparametric regression estimation and have received great attention in the literature. Their simplest version, the local constant estimator, can be easily extended to the errors-in-variables context by exploiting its similarity with the deconvolution kernel density estimator. The generalization of the higher order versions of the estimator, however, is not straightforward and has remained an open problem for the last 15 years. We propose an innovative local polynomial estimator of any order in the errors-in-variables context, derive its design-adaptive asymptotic properties and study its finite sample performance on simulated examples. We provide not only a solution to a long-standing open problem, but also provide methodological contributions to error-invariable regression, including local polynomial estimation of derivative functions.

  15. Coil Designs for Novel Magnetic Geometries to Cure the Divertor Heat Flux Problem for Reactors

    Science.gov (United States)

    Pekker, M.; Valanju, P.; Kotschenreuther, M.; Wiley, J. C.; Strickler, D.

    2004-11-01

    Coil designs are developed for novel magnetic divertor geometries with a second axi-symmetric x-point and flux expansion region along the separatrix. Adjacent posters describe how these lead to spreading of heat flux and the possibility of stable, complete detachment to overcome serious physics and engineering problems in reactors. The principal feasibility issue is creating, with simple coils, additional X-points on the separatrix without extensively deforming the magnetic field in the main plasma. For the spherical tokamak NSTX, we show that adding one or two poloidal coils suffices to create a divergent flux at the divertor, i.e., a new x-point. The currents and forces for the extra coils are small. We also modify ARIES ST design to show reactor feasibility. Optimized coil designs for PEGASUS, ARIES RS/AT, and a modular ITER retrofit are also being developed. For our calculations we used self consistent code FBEQ, which was used to design NSTX. We also use NCSX tools for optimization of designs with competing physics and engineering constraints.

  16. Design and analysis of concrete reactor vessels: New developments, problems and trends

    International Nuclear Information System (INIS)

    Bazant, Z.P.

    1984-01-01

    This lecture reviews new developments in analysis and design of prestressed concrete reactor vessels (PCRV). After a brief assessment of the current status and experience, the advantages, disadvantages, and especially the safety features of PCRV, are discussed. Attention is then focused on the design of penetrations and openings, and on the design for high-temperature resistance - areas in which further developments are needed. Various possible designs for high-temperature exposure of concrete in a hypothetical accident are analyzed. Considered are not only PCRVs for gas-cooled reactors (GCR), but also guard vessels for liquid metal fast breeder reactors (LMFBR), for which designs mitigating the adverse effects of molten sodium, molten steel, and core melt are surveyed. Realistic analysis of the problems requires further development in the knowledge of material behavior and its mathematical modeling. Recent advances in the modeling of high-temperature response of concrete, including pore water transfer, pore pressure, creep and shrinkage are outlined. This is followed by a discussion of new developments in the analysis of cracking of concrete, where the need of switching from stress criteria to energy criteria for fracture is emphasized. The lecture concludes with a brief discussion of long-time behavior, the effect of aging, and probabilistic analysis of creep. (orig.)

  17. Interactive program for analysis and design problems in advanced composites technology

    Science.gov (United States)

    Cruse, T. A.; Swedlow, J. L.

    1971-01-01

    During the past year an experimental program in the fracture of advanced fiber composites has been completed. The experimental program has given direction to additional experimental and theoretical work. A synthesis program for designing low weight multifastener joints in composites is proposed, based on extensive analytical background. A number of failed joints have been thoroughly analyzed to evaluate the failure hypothesis used in the synthesis procedure. Finally, a new solution is reported for isotropic and anisotropic laminates using the boundary-integral method. The solution method offers significant savings of computer core and time for important problems.

  18. A Dynamic Programming-Based Heuristic for the Shift Design Problem in Airport Ground Handling

    DEFF Research Database (Denmark)

    Clausen, Tommy

    We consider the heterogeneous shift design problem for a workforce with multiple skills, where work shifts are created to cover a given demand as well as possible while minimizing cost and satisfying a flexible set of constraints. We focus mainly on applications within airport ground handling where...... the demand can be highly irregular and specified on time intervals as short as five minutes. Ground handling operations are subject to a high degree of cooperation and specialization that require workers with different qualifications to be planned together. Different labor regulations or organizational rules...

  19. Efficient cryptographic substitution box design using travelling salesman problem and chaos

    Directory of Open Access Journals (Sweden)

    Musheer Ahmad

    2016-09-01

    Full Text Available Symmetric encryption has been a standout amongst the most reliable option by which security is accomplished. In modern block symmetric cyphers, the substitution-boxes have been playing a critical role of nonlinear components that drives the actual security of cyphers. In this paper, the travelling salesman problem and piece-wise linear chaotic map are explored to synthesize an efficient configuration of 8 × 8 substitution-box. The proposed anticipated design has the consistency which is justified by the standard performance indexes. The statistical results manifest that the prospective substitution-box is cryptographically more impressive as compared to some recent investigations.

  20. A service flow model for the liner shipping network design problem

    DEFF Research Database (Denmark)

    Plum, Christian Edinger Munk; Pisinger, David; Sigurd, Mikkel M.

    2014-01-01

    Global liner shipping is a competitive industry, requiring liner carriers to carefully deploy their vessels efficiently to construct a cost competitive network. This paper presents a novel compact formulation of the liner shipping network design problem (LSNDP) based on service flows....... The model ensures strictly weekly frequencies of services, ensures that port-vessel draft capabilities are not violated, respects vessel capacities and the number of vessels available. The profit of the generated network is maximized, i.e. the revenue of flowed cargo subtracted operational costs...... of the network and a penalty for not flowed cargo. The model can be used to design liner shipping networks to utilize a container carrier’s assets efficiently and to investigate possible scenarios of changed market conditions. The model is solved as a Mixed Integer Program. Results are presented for the two...

  1. An Integrated Approach for Reliable Facility Location/Network Design Problem with Link Disruption

    Directory of Open Access Journals (Sweden)

    Davood Shishebori

    2015-05-01

    Full Text Available Proposing a robust designed facility location is one of the most effective ways to hedge against unexpected disruptions and failures in a transportation network system. This paper considers the combined facility location/network design problem with regard to transportation link disruptions and develops a mixed integer linear programming formulation to model it. With respect to the probability of link disruptions, the objective function of the model minimizes the total costs, including location costs, link construction costs and also the expected transportation costs. An efficient hybrid algorithm based on LP relaxation and variable neighbourhood search metaheuristic is developed in order to solve the mathematical model. Numerical results demonstrate that the proposed hybrid algorithm has suitable efficiency in terms of duration of solution time and determining excellent solution quality.

  2. A Mathematical Formulation of the SCOLE Control Problem. Part 2: Optimal Compensator Design

    Science.gov (United States)

    Balakrishnan, A. V.

    1988-01-01

    The study initiated in Part 1 of this report is concluded and optimal feedback control (compensator) design for stability augmentation is considered, following the mathematical formulation developed in Part 1. Co-located (rate) sensors and (force and moment) actuators are assumed, and allowing for both sensor and actuator noise, stabilization is formulated as a stochastic regulator problem. Specializing the general theory developed by the author, a complete, closed form solution (believed to be new with this report) is obtained, taking advantage of the fact that the inherent structural damping is light. In particular, it is possible to solve in closed form the associated infinite-dimensional steady-state Riccati equations. The SCOLE model involves associated partial differential equations in a single space variable, but the compensator design theory developed is far more general since it is given in the abstract wave equation formulation. The results thus hold for any multibody system so long as the basic model is linear.

  3. Designing a Strategic Measurement Program for Software Engineering Organizations: Discovering Difficulties and Problems

    Directory of Open Access Journals (Sweden)

    Mitre-Hernández Hugo A.

    2014-04-01

    Full Text Available Software measurement is widely recognized as an essential part of understanding, controlling, monitoring, predicting, and evaluating software development and maintenance projects. Both, software process improvement (SPI and software measurement literature include many case studies of successful companies and descriptions of their measurement programs. However, there are still concerns on how to design efficient strategic measurement programs. These concerns include the lack of involvement of the SEO’s personnel, bad alignment with its strategy and improvement initiative, difficulty to justify the utility of using standards or improvement initiatives, etc. All of the former results in inadequate measurement programs that often lead to poor decisions and economic loss. This paper describes a pilot study to observe and analyze the operation of measurement teams when using measurement methods such as Balanced Objective-Quantifiers Method (BOQM, Practical Software Measurement (PSM and Balanced Scorecard and Goal-Driven Measurement (BSC&GQ[I]M to design a strategic measurement program. From the results of the study, we gained some insight on common difficulties and problems, which are useful to consider when designing of strategic measurement programs. This paper describes an important milestone in achieving our main research goal, evaluate and find suggestions to design a strategic measurement program aligned correctly with the strategic goals, for effective decision making at all organization levels and justify the utilities or benefits of integrating improvement initiatives.

  4. Problems related to design and construction of industrial radiography exposure room - an experience

    International Nuclear Information System (INIS)

    Siti Madiha Muhammad Amir; Mohd Khairi Mohd Said; Abdul Nassir Ibrahim; Ab Razak Hamzah

    2009-01-01

    In Non-Destructive Testing (NDT), especially in radiography method, inspections of components are executed either on-site or in-house. For in-house inspections, work must be performed in a specially constructed exposure room. The design of the exposure room must be according to specific requirements described in various documents related to radiation safety. Stringent requirements specified for the exposure room is for the purpose of ensuring the safety of public and radiation workers. These requirements are never compromised. One of the AELB requirements that need to be complied is that the permissible dose limit anywhere outside the room must be less than 0.25 mR/hr. In designing and constructing the exposure room, many factors must be taken into account such as shielding thickness, density of shielding, thickness of lead door, the roof design of the exposure room and many more. This paper highlights problems encountered and the considerations taken to design and construct the exposure room so that the exposure room will comply with the permissible dose limit set by the regulatory body. (Author)

  5. Software design as a problem in learning theory (a research overview)

    Science.gov (United States)

    Fass, Leona F.

    1992-01-01

    Our interest in automating software design has come out of our research in automated reasoning, inductive inference, learnability, and algebraic machine theory. We have investigated these areas extensively, in connection with specific problems of language representation, acquisition, processing, and design. In the case of formal context-free (CF) languages we established existence of finite learnable models ('behavioral realizations') and procedures for constructing them effectively. We also determined techniques for automatic construction of the models, inductively inferring them from finite examples of how they should 'behave'. These results were obtainable due to appropriate representation of domain knowledge, and constraints on the domain that the representation defined. It was when we sought to generalize our results, and adapt or apply them, that we began investigating the possibility of determining similar procedures for constructing correct software. Discussions with other researchers led us to examine testing and verification processes, as they are related to inference, and due to their considerable importance in correct software design. Motivating papers by other researchers, led us to examine these processes in some depth. Here we present our approach to those software design issues raised by other researchers, within our own theoretical context. We describe our results, relative to those of the other researchers, and conclude that they do not compare unfavorably.

  6. Natural Model based Design in Context: an Effective Method for Environmental Problems

    Directory of Open Access Journals (Sweden)

    Eric D. Kameni

    2017-10-01

    Full Text Available Analyzing complex problem domains is not easy. Simulation tools support decision makers to find the best policies. Model-based system development is an approach where a model of the application domain is the central driving force when designing simulation tools. State-of-the-art techniques however still require both expert knowledge of the application domain and the implementation techniques as provided by ICT (such as multilevel agent technology. Domain experts, however, usually do not master ICT sufficiently. Modeling is more insightful for the domain expert when its goal is to formalize the language being used in that domain as a semi-natural language. At the meta level, this language describes the main concepts of the type of application domain. The model then is a concretization of this meta model. The main focus of this article is (1 to propose a natural-language-based approach to modeling application domains, (2 to show how these models can be transformed systematically into computational models, and (3 to propose the tool TiC (Tool in Context that supports the domain expert when developing a model and generating a simulation tool. Our research methodology is based on Design Science. We verify our approach by describing the various transformation steps in detail, and by demonstrating the way of working via a sample session applying a real problem of Laf Forest Reserve deforestation in North Cameroon.

  7. Solution Algorithm for a New Bi-Level Discrete Network Design Problem

    Directory of Open Access Journals (Sweden)

    Qun Chen

    2013-12-01

    Full Text Available A new discrete network design problem (DNDP was pro-posed in this paper, where the variables can be a series of integers rather than just 0-1. The new DNDP can determine both capacity improvement grades of reconstruction roads and locations and capacity grades of newly added roads, and thus complies with the practical projects where road capacity can only be some discrete levels corresponding to the number of lanes of roads. This paper designed a solution algorithm combining branch-and-bound with Hooke-Jeeves algorithm, where feasible integer solutions are recorded in searching the process of Hooke-Jeeves algorithm, lend -ing itself to determine the upper bound of the upper-level problem. The thresholds for branch cutting and ending were set for earlier convergence. Numerical examples are given to demonstrate the efficiency of the proposed algorithm.

  8. The Component Packaging Problem: A Vehicle for the Development of Multidisciplinary Design and Analysis Methodologies

    Science.gov (United States)

    Fadel, Georges; Bridgewood, Michael; Figliola, Richard; Greenstein, Joel; Kostreva, Michael; Nowaczyk, Ronald; Stevenson, Steve

    1999-01-01

    This report summarizes academic research which has resulted in an increased appreciation for multidisciplinary efforts among our students, colleagues and administrators. It has also generated a number of research ideas that emerged from the interaction between disciplines. Overall, 17 undergraduate students and 16 graduate students benefited directly from the NASA grant: an additional 11 graduate students were impacted and participated without financial support from NASA. The work resulted in 16 theses (with 7 to be completed in the near future), 67 papers or reports mostly published in 8 journals and/or presented at various conferences (a total of 83 papers, presentations and reports published based on NASA inspired or supported work). In addition, the faculty and students presented related work at many meetings, and continuing work has been proposed to NSF, the Army, Industry and other state and federal institutions to continue efforts in the direction of multidisciplinary and recently multi-objective design and analysis. The specific problem addressed is component packing which was solved as a multi-objective problem using iterative genetic algorithms and decomposition. Further testing and refinement of the methodology developed is presently under investigation. Teaming issues research and classes resulted in the publication of a web site, (http://design.eng.clemson.edu/psych4991) which provides pointers and techniques to interested parties. Specific advantages of using iterative genetic algorithms, hurdles faced and resolved, and institutional difficulties associated with multi-discipline teaming are described in some detail.

  9. Motivational Design and Problem-Based Learning May Increase Student Engagement in Information Literacy Instruction Sessions

    Directory of Open Access Journals (Sweden)

    Ann Glusker

    2017-12-01

    Full Text Available A Review of: Roberts, L. (2017. Research in the real world: Improving adult learners web search and evaluation skills through motivational design and problem-based learning. College & Research Libraries, 78(4, 527-551. https://doi.org/10.5860/crl.78.4.527 Abstract Objective – To determine whether the use of the ARCS (Attention, Relevance, Confidence, and Satisfaction Model of Motivational Design, combined with the Problem-Based Learning approach, improves the skills, confidence, and perception of workshop relevance among non-traditional students in information literacy sessions. Design – Experimental study, one group pre-test and post-test. Setting – Community college in Denver, Colorado, United States. Subjects – 41 community college students. Methods – A convenience sample of three community college student groups each attended an information literacy session. The session was constructed using principles and strategies outlined in the ARCS Model of Motivational Design and the Problem-Based Learning approach. Pre-test and post-test instruments were developed by the author after a literature review. The students were given the information literacy-related pretest before the session. After receiving instruction, the comparable posttest (with different literacy challenges was administered. Main Results – A comparison of the pre-test and post-test results showed that there were increases in the students’ search skills; their confidence in their own search skills; and their perceptions of workshop relevance in relation to their needs and to real-world situations. Conclusion – This study focuses on the use of motivational design for information literacy instruction. It addresses a gap in the research literature, as it explicitly examines issues of concern regarding the instruction of non-traditional students. The conjunction of the ARCS Model and Problem-Based Learning is considered to be an effective strategy for improving learning

  10. Cross-disciplinary problem-solving workshop: a pedagogical approach to anticipate ergonomist engineering design collaboration.

    Science.gov (United States)

    Brunier, Elisabeth; Le Chapellier, Michel; Dejean, Pierre Henri

    2012-01-01

    The aims of this paper are to present concept and results of an innovative educational model approach based on ergonomics involvement in industrial project. First we present Cross disciplinary Problem solving Workshop by answering three questions:1) What is a CPW: A partnership between Universities and one or several companies, purposes of it are first to increase health, well being, companies teams competencies, and competitiveness, second to train the "IPOD generation" to include risks prevention in design. 2) How does it work? CPW allows cooperation between experience and new insight through inductive methods. This model follows the Piaget (1) philosophy linking concrete world to abstraction by a learning system associating realization and abstraction. 3) Is it successful? In order to answer this third question we will show examples of studies and models performed during CPWs.It appears that the CPWs produce visible results in companies such as new process designs, new methods, and also changes in lectures. However some less visible results remain unclear: How the company personnel evolve during and after CPW? Does CPW motivate our future engineers enough to continuously improve their skills in risk prevention and innovative design?

  11. The Primary Experiments of an Analysis of Pareto Solutions for Conceptual Design Optimization Problem of Hybrid Rocket Engine

    Science.gov (United States)

    Kudo, Fumiya; Yoshikawa, Tomohiro; Furuhashi, Takeshi

    Recentry, Multi-objective Genetic Algorithm, which is the application of Genetic Algorithm to Multi-objective Optimization Problems is focused on in the engineering design field. In this field, the analysis of design variables in the acquired Pareto solutions, which gives the designers useful knowledge in the applied problem, is important as well as the acquisition of advanced solutions. This paper proposes a new visualization method using Isomap which visualizes the geometric distances of solutions in the design variable space considering their distances in the objective space. The proposed method enables a user to analyze the design variables of the acquired solutions considering their relationship in the objective space. This paper applies the proposed method to the conceptual design optimization problem of hybrid rocket engine and studies the effectiveness of the proposed method.

  12. A globally most violated cutting plane method for complex minimax problems with application to digital filter design

    Science.gov (United States)

    Potchinkov, A.; Reemtsen, R.

    1993-12-01

    In [4,6], the authors have presented a numerical method for the solution of complex minimax problems, which implicitly solves discretized versions of the equivalent semi-infinite programming problem on increasingly finer grids. While this method only requires the most violated constraint at the current iterate on a finite subset of the infinitely many constraints of the problem, we consider here a related and more direct approach (applicable to general convex semi-infinite programming problems) which makes use of the globally most violated constraint. Numerical examples with up to 500 unknowns, which partially originate from digital filter design problems, are discussed.

  13. High-resolution coupled physics solvers for analysing fine-scale nuclear reactor design problems

    Science.gov (United States)

    Mahadevan, Vijay S.; Merzari, Elia; Tautges, Timothy; Jain, Rajeev; Obabko, Aleksandr; Smith, Michael; Fischer, Paul

    2014-01-01

    An integrated multi-physics simulation capability for the design and analysis of current and future nuclear reactor models is being investigated, to tightly couple neutron transport and thermal-hydraulics physics under the SHARP framework. Over several years, high-fidelity, validated mono-physics solvers with proven scalability on petascale architectures have been developed independently. Based on a unified component-based architecture, these existing codes can be coupled with a mesh-data backplane and a flexible coupling-strategy-based driver suite to produce a viable tool for analysts. The goal of the SHARP framework is to perform fully resolved coupled physics analysis of a reactor on heterogeneous geometry, in order to reduce the overall numerical uncertainty while leveraging available computational resources. The coupling methodology and software interfaces of the framework are presented, along with verification studies on two representative fast sodium-cooled reactor demonstration problems to prove the usability of the SHARP framework. PMID:24982250

  14. A hybrid approach to solving the problem of design of nuclear fuel cells

    International Nuclear Information System (INIS)

    Montes T, J. L.; Perusquia del C, R.; Ortiz S, J. J.; Castillo, A.

    2015-09-01

    An approach to solving the problem of fuel cell design for BWR power reactor is presented. For this purpose the hybridization of a method based in heuristic knowledge rules called S15 and the advantages of a meta-heuristic method is proposed. The synergy of potentialities of both techniques allows finding solutions of more quality. The quality of each solution is obtained through a multi-objective function formed from the main cell parameters that are provided or obtained during the simulation with the CASMO-4 code. To evaluate this alternative of solution nuclear fuel cells of reference of nuclear power plant of Laguna Verde were used. The results show that in a systematic way the results improve when both methods are coupled. As a result of the hybridization process of the mentioned techniques an improvement is achieved in a range of 2% with regard to the achieved results in an independent way by the S15 method. (Author)

  15. How to solve materials and design problems in solar heating and cooling. Energy technology review No. 77

    Energy Technology Data Exchange (ETDEWEB)

    Ward, D.S.; Oberoi, H.S.; Weinstein, S.D.

    1982-01-01

    A broad range of difficulties encountered in active and passive solar space heating systems and active solar space cooling systems is covered. The problems include design errors, installation mistakes, inadequate durability of materials, unacceptable reliability of components, and wide variations in performance and operation of different solar systems. Feedback from designers and manufacturers involved in the solar market is summarized. The designers' experiences with and criticisms of solar components are presented, followed by the manufacturers' replies to the various problems encountered. Information is presented on the performance and operation of solar heating and cooling systems so as to enable future designs to maximize performance and eliminate costly errors. (LEW)

  16. An MPCC Formulation and Its Smooth Solution Algorithm for Continuous Network Design Problem

    Directory of Open Access Journals (Sweden)

    Guangmin Wang

    2017-12-01

    Full Text Available Continuous network design problem (CNDP is searching for a transportation network configuration to minimize the sum of the total system travel time and the investment cost of link capacity expansions by considering that the travellers follow a traditional Wardrop user equilibrium (UE to choose their routes. In this paper, the CNDP model can be formulated as mathematical programs with complementarity constraints (MPCC by describing UE as a non-linear complementarity problem (NCP. To address the difficulty resulting from complementarity constraints in MPCC, they are substituted by the Fischer-Burmeister (FB function, which can be smoothed by the introduction of the smoothing parameter. Therefore, the MPCC can be transformed into a well-behaved non-linear program (NLP by replacing the complementarity constraints with a smooth equation. Consequently, the solver such as LINDOGLOBAL in GAMS can be used to solve the smooth approximate NLP to obtain the solution to MPCC for modelling CNDP. The numerical experiments on the example from the literature demonstrate that the proposed algorithm is feasible.

  17. An Evaluation of Resource Development and Dissemination Activities Designed to Promote Problem-Based Learning at the University of Ulster

    Science.gov (United States)

    Hack, Catherine; McKillop, Aine; Sweetman, Sandra; McCormack, Jacqueline

    2015-01-01

    The transition from traditional instruction to a problem-based approach to learning requires many changes for educators and for students. The aim of this project was to develop an online problem-based learning (PBL) resource centre to provide academic staff from across the University with support in incorporating PBL in their curriculum design.…

  18. The Development of Online Tutorial Program Design Using Problem-Based Learning in Open Distance Learning System

    Science.gov (United States)

    Said, Asnah; Syarif, Edy

    2016-01-01

    This research aimed to evaluate of online tutorial program design by applying problem-based learning Research Methods currently implemented in the system of Open Distance Learning (ODL). The students must take a Research Methods course to prepare themselves for academic writing projects. Problem-based learning basically emphasizes the process of…

  19. A nonlinear control design for energy sink simulation in the Euler-Poinsot problem

    Science.gov (United States)

    Kammer, Daniel C.; Gray, Gary L.

    1993-01-01

    A nonlinear control design is presented for the purpose of quantitatively simulating the effects of internal damping mechanisms modeled as energy sinks on the attitude dynamics of rigid body spacecraft. Damping is important because it is often the driving mechanism behind passive attitude acquisition maneuvers. Introduction of the controller into the Euler attitude equations of motion allows for the explicit representation of damping without the introduction of additional degrees of freedom required for a physical damping mechanism. This result is significant because perturbation techniques which rely on the closed form solution of the unperturbed problem can then be used to analyze the effects of perturbations upon a damped system. The controller is designed to dissipate kinetic energy while maintaining the magnitude of the angular momentum vector. Control torques are nonlinear functions of the angular momentum components expressed in a body-fixed frame. A numerical simulation of an actual damping mechanism during a decay from minor axis spin into a flat spin is presented showing that the nonlinear controller gives a good qualitative representation and, in many instances, a good quantitative approximation of the attitude motion of a representative spacecraft containing a damping mechanism.

  20. Formulation and Validation of Multidisciplinary Design Problem on Wear and Fatigue Life of Lead Screw Actuators

    Directory of Open Access Journals (Sweden)

    Krishna Meruva

    2013-01-01

    Full Text Available Multidisciplinary design optimization has been widely applied in the optimization of large-scale complex system and also in the design and optimization of components, which are involved in multidisciplinary behaviors. The wear and fatigue life of lead screw actuators is a typical multidisciplinary problem. The wear behaviors of actuators closely relate to many factors such as loads, lubrications, materials properties, surface properties, pressures, and temperature. Therefore, the wear and fatigue life of actuators cannot be modeled without a simultaneous consideration of solid mechanics, fluid dynamics, contact mechanics, and thermal dynamics. In this paper, the wear and fatigue life of a lead screw actuator is modeled and validated. Firstly, the theory of asperity contact and Archard’s model of sliding wear are applied to estimate the amount of wear under certain circumstances. Secondly, a test platform is developed based on a standard ASTM test protocol, and the wear phenomenon at the ball-on-flat sliding is measured to validate the developed wear model. Thirdly, finite element analysis is conducted using Nastran to assess the contact stresses in the lead screw and nut assembly model. The estimated data from the three sources are finally merged to formulate a mathematical model in predicting the wear and fatigue life for the optimization of lead screw actuators.

  1. Tabu search methods for multicommodity capcitated fixed charge network design problem

    Energy Technology Data Exchange (ETDEWEB)

    Crainic, T.; Farvolden, J.; Gendreau, M.; Soriano, P.

    1994-12-31

    We address the fixed charge capacitated multicommodity network flow problem with linear costs and no additional side constraints, and present two solution approaches based on the tabu search metaheuristic. In the first case, the search is conducted by exploring the space of the design (integer) variables, while neighbors are evaluated and moves are selected via a capacitated multicommodity minimum cost network flow subproblem. The second approach integrates simplex pivoting rules into a tabu search framework. Here, the search explores the space of flow path variables when all design arcs are open, by using column generation to obtain new variables, and pivoting to determine and evaluate the neighbors of any given solution. Adapting this idea within our tabu search framework represents an interesting challenge, since several of the standard assumptions upon which column generation schemes are based are no longer verified. In particular, the monotonic decrease of the objective function value is no longer ensured, and both variable and fixed costs characterize arcs. On the other hand, the precise definition and generation of the tabu search neighborhoods in a column generation context poses an additional challenge, linked particularly to the description and identification of path variables. We describe the various components, implementation challenges and behaviour of each of the two algorithms, and compare their computational and solution quality performance. Comparisons with known bounding procedures will be presented as well.

  2. On Stackelberg and Inverse Stackelberg Games and Their Applications in the Optimal Toll Design Problem, the Energy Markets Liberalization Problem, and in the Theory of Incentives

    International Nuclear Information System (INIS)

    Stankova, K.

    2009-01-01

    Inverse (or reverse) Stackelberg games have become the subject of recent game theory research, as a special type or as an extension of Stackelberg games. So far, only very little theory about inverse Stackelberg games is available and the available theory is still in its infancy. In this thesis we focus on theoretically solving such problems and we propose to treat several challenging problems in various fields inside this framework. In Stackelberg games a so-called leader determines actions for one or more so-called followers. The problem of finding an optimal strategy for the leader in these games is in general extremely hard to solve, and often even completely unsolvable. Starting from simple static problems and proceeding to more difficult dynamic ones, we show how to find the optimal strategy for the leader in a heuristic manner. In this thesis, the application of game theory is proposed in the following domains: The optimal toll design problem, the electricity markets liberalization problem, and the theory of incentives. The optimal toll design problem is a game of the Stackelberg type in which a road authority acts as the leader and drivers in the road network act as the followers. The road authority sets tolls on some of the links in the network in order to maximize its objective function, while the drivers make their travel decisions in order to minimize their perceived travel costs. If the toll that the road authority sets is traffic-flow invariant, the problem is the 'classical' Stackelberg game; if the toll is traffic-flow dependent, the problem is of the inverse Stackelberg type. We determine the optimal traffic-flow dependent toll for the road authority for both static and dynamic variants of the problem. If the solution concept for the drivers' behavior is the deterministic user equilibrium, the problem can be dealt with analytically. If the stochastic user equilibrium applies, numerical methods have to be applied to find a solution. As the problem

  3. Design of a Maglev Vibration Test Platform for the Research of Maglev Vehicle-girder Coupled Vibration Problem

    OpenAIRE

    Zhou Danfeng; Wang Lianchun; Li Jie; Yu Peichang

    2017-01-01

    The maglev vehicle-girder coupled vibration problem has been encountered in many maglev test or commercial lines, which significantly degrade the performance of the maglev train. In previous research on the principle of the coupled vibration problem, it has been discovered that the fundamental model of the maglev girder can be simplified as a series of mass-spring resonators of different but related resonance frequencies, and that the stability of the vehicle-girder coupled system can be inve...

  4. Using an Animal Group Vigilance Practical Session to Give Learners a "Heads-Up" to Problems in Experimental Design

    Science.gov (United States)

    Rands, Sean A.

    2011-01-01

    The design of experimental ecological fieldwork is difficult to teach to classes, particularly when protocols for data collection are normally carefully controlled by the class organiser. Normally, reinforcement of the some problems of experimental design such as the avoidance of pseudoreplication and appropriate sampling techniques does not occur…

  5. The time constrained multi-commodity network flow problem and its application to liner shipping network design

    DEFF Research Database (Denmark)

    Karsten, Christian Vad; Pisinger, David; Røpke, Stefan

    2015-01-01

    The multi-commodity network flow problem is an important sub-problem in several heuristics and exact methods for designing route networks for container ships. The sub-problem decides how cargoes should be transported through the network provided by shipping routes. This paper studies the multi......-commodity network flow problem with transit time constraints which puts limits on the duration of the transit of the commodities through the network. It is shown that for the particular application it does not increase the solution time to include the transit time constraints and that including the transit time...

  6. On the inverse problem of blade design for centrifugal pumps and fans

    Science.gov (United States)

    Kruyt, N. P.; Westra, R. W.

    2014-06-01

    The inverse problem of blade design for centrifugal pumps and fans has been studied. The solution to this problem provides the geometry of rotor blades that realize specified performance characteristics, together with the corresponding flow field. Here a three-dimensional solution method is described in which the so-called meridional geometry is fixed and the distribution of the azimuthal angle at the three-dimensional blade surface is determined for blades of infinitesimal thickness. The developed formulation is based on potential-flow theory. Besides the blade impermeability condition at the pressure and suction side of the blades, an additional boundary condition at the blade surface is required in order to fix the unknown blade geometry. For this purpose the mean-swirl distribution is employed. The iterative numerical method is based on a three-dimensional finite element method approach in which the flow equations are solved on the domain determined by the latest estimate of the blade geometry, with the mean-swirl distribution boundary condition at the blade surface being enforced. The blade impermeability boundary condition is then used to find an improved estimate of the blade geometry. The robustness of the method is increased by specific techniques, such as spanwise-coupled solution of the discretized impermeability condition and the use of under-relaxation in adjusting the estimates of the blade geometry. Various examples are shown that demonstrate the effectiveness and robustness of the method in finding a solution for the blade geometry of different types of centrifugal pumps and fans. The influence of the employed mean-swirl distribution on the performance characteristics is also investigated.

  7. An algorithm for solving the time-constrained multicommodity flow problem with applications in liner shipping network design

    DEFF Research Database (Denmark)

    Karsten, Christian Vad; Pisinger, David; Røpke, Stefan

    The liner shipping network design problem has proven to be hard to solve. However, well-designed route nets are paramount to liner shipping companies both in terms of competitiveness and environmental impact. Fast evaluations of the multicommodity flow subproblem is one of the bottlenecks when...... determining the optimal routing and fleet deployment in the network design problem. Additionally, most existing models do not consider the level of service. To accommodate that, we present an algorithm for solving the multicommodity flow subproblem with limits on commodity travel time....

  8. Treatment Rationale and Design for J-AXEL: A Randomized Phase 3 Study Comparing Nab-Paclitaxel With Docetaxel in Patients With Previously Treated Advanced Non-Small-Cell Lung Cancer.

    Science.gov (United States)

    Yoneshima, Yasuto; Morita, Satoshi; Ando, Masahiko; Miura, Satoru; Yoshioka, Hiroshige; Abe, Tetsuya; Kato, Terufumi; Kondo, Masashi; Hosomi, Yukio; Hotta, Katsuyuki; Yamamoto, Nobuyuki; Kishimoto, Junji; Nakanishi, Yoichi; Okamoto, Isamu

    2017-01-01

    Nanoparticle albumin-bound (nab) paclitaxel is a promising new therapeutic agent for all histologic types of non-small-cell lung cancer (NSCLC). We recently performed a phase 2 study of weekly nab-paclitaxel in patients with previously treated advanced NSCLC, finding promising activity and acceptable toxicity for this regimen. We have now designed a randomized phase 3 intergroup study (J-AXEL, UMIN000017487) to examine the clinical benefit and safety of nab-paclitaxel compared to docetaxel in patients with previously treated advanced NSCLC. Patients are randomized to receive either docetaxel (60 mg/m 2 on day 1 every 3 weeks, control arm) or nab-paclitaxel (100 mg/m 2 on days 1, 8, and 15 every 3 weeks, experimental arm), with each drug being administered until disease progression or unacceptable toxicity. The study will evaluate the noninferiority of nab-paclitaxel relative to docetaxel for the primary end point of overall survival. If the primary objective is achieved, this study will provide evidence for a new alternative treatment option for patients with previously treated advanced NSCLC. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Social implication design (SID) : A design method to exploit the unique value of the artefact to counteract social problems

    NARCIS (Netherlands)

    Tromp, N.; Hekkert, P.P.M.

    2014-01-01

    The role of design in changing people’s behaviour and causing social implications has been referred to as an inherent aspect of design. In taking responsibility for this influence of design, emphasis is often placed on the prevention of undesired consequences rather than the realization of desired

  10. Access to digital library databases in higher education: design problems and infrastructural gaps.

    Science.gov (United States)

    Oswal, Sushil K

    2014-01-01

    After defining accessibility and usability, the author offers a broad survey of the research studies on digital content databases which have thus far primarily depended on data drawn from studies conducted by sighted researchers with non-disabled users employing screen readers and low vision devices. This article aims at producing a detailed description of the difficulties confronted by blind screen reader users with online library databases which now hold most of the academic, peer-reviewed journal and periodical content essential for research and teaching in higher education. The approach taken here is borrowed from descriptive ethnography which allows the author to create a complete picture of the accessibility and usability problems faced by an experienced academic user of digital library databases and screen readers. The author provides a detailed analysis of the different aspects of accessibility issues in digital databases under several headers with a special focus on full-text PDF files. The author emphasizes that long-term studies with actual, blind screen reader users employing both qualitative and computerized research tools can yield meaningful data for the designers and developers to improve these databases to a level that they begin to provide an equal access to the blind.

  11. Designing, implementing and evaluating an online problem-based learning (PBL) environment--a pilot study.

    Science.gov (United States)

    Ng, Manwa L; Bridges, Susan; Law, Sam Po; Whitehill, Tara

    2014-01-01

    Problem-based learning (PBL) has been shown to be effective for promoting student competencies in self-directed and collaborative learning, critical thinking, self-reflection and tackling novel situations. However, the need for face-to-face interactions at the same place and time severely limits the potential of traditional PBL. The requirements of space and for meeting at a specific location at the same time create timetabling difficulties. Such limitations need to be tackled before all potentials of PBL learning can be realized. The present study aimed at designing and implementing an online PBL environment for undergraduate speech/language pathology students, and assessing the associated pedagogical effectiveness. A group of eight PBL students were randomly selected to participate in the study. They underwent 4 weeks of online PBL using Adobe Connect. Upon completion of the experiment, they were assessed via a self-reported questionnaire and quantitative comparison with traditional PBL students based on the same written assignment. The questionnaire revealed that all participating students enjoyed online PBL, without any perceived negative effects on learning. Online PBL unanimously saved the students travel time to and from school. Statistical analysis indicated no significant difference in assignment grades between the online and traditional PBL groups, indicating that online PBL learning appears to be similarly effective as traditional face-to-face PBL learning.

  12. Design solutions to interface flow problems: Text - List of symbols - References

    International Nuclear Information System (INIS)

    1986-01-01

    All published proposals for the deep level burial of radioactive waste recognise that the access shafts, tunnels and boreholes must be sealed, and that the sealing of these openings plays an integral role in the overall isolation of the waste. Previous studies have identified the interface between the host ground formation and the various sealing materials as potential defects in the overall quality of the waste isolation. The significance of groundwater flow at and near the interface has been assessed for representative conditions in generic repository materials. A range of design options to minimise the significance of flow in the interface zone have been proposed, and the most practical of these options have been selected for quantitative analysis. It has been found that isolated high impermeability collars are of limited value unless a highly effective method of minimising ground disturbance during excavation can be developed. It has also been found that control of radionuclide migration by sorptive processes provides an attractive option. The effect of various geometrical arrangements of sorptive materials has been investigated. Consideration has also been given to the particular conditions in the near field, to the behaviour of weak plastic clay host formations and to the mechanical interaction between the backfill material and the host formation

  13. [Effects of the new comprehensive system for designating illegal drug components on the abuse of designer drugs and future problems based on an online questionnaire].

    Science.gov (United States)

    Morino, Taichi; Okazaki, Mitsuhiro; Toda, Takaki; Yokoyama, Takashi

    2015-12-01

    Recently, the abuse of designer drugs has become a social problem. Designer drugs are created by modifying part of the chemical structure of drugs that have already been categorized as illegal, thereby creating a different chemical compound in order to evade Pharmaceutical Affairs Law regulations. The new comprehensive system for designating illegal drug components has been in effect since March 2013, and many designer drugs can now be regulated. We conducted an online questionnaire survey of people with a history of designer drug use to elucidate the effects of the new system on the abuse of designer drugs and to identify potential future problems. Over half the subjects obtained designer drugs only before the new system was implemented. Awareness of the system was significantly lower among subjects who obtained designer drugs for the first time after its introduction than those who obtained the drugs only before its implementation. Due to the new system, all methods of acquiring designer drugs saw decreases in activity. However, the ratio of the acquisition of designer drugs via the Internet increased. Since over 50% of the subjects never obtained designer drugs after the new system was introduced, goals that aimed to make drug procurement more difficult were achieved. However, awareness of the new system among subjects who obtained designer drugs after the new system was introduced was significantly low. Therefore, fostering greater public awareness of the new system is necessary. The results of the questionnaire also suggested that acquiring designer drugs through the Internet has hardly been affected by the new system. We strongly hope that there will be a greater push to restrict the sale of designer drugs on the Internet in the near future.

  14. Co-designing Usable Knowledge with Stakeholders and Fostering Ownership - A Pathway through the communication problem?

    Science.gov (United States)

    Schmale, J.; von Schneidemesser, E.; Chabay, I.; Maas, A.; Lawrence, M. G.

    2013-12-01

    to present-day problems in contrast to only focusing on the long-term time scales of CO2-driven climate change, the ClimPol project goes beyond the academic realm and collaborates with a variety of stakeholders across scales from local to international to investigate potential options for joint and sustainable policies. The underlying assumption is that each stakeholder community possesses their own knowledge system which contributes an important piece to the puzzle which is necessary to assemble for creating solutions. We call this approach co-designing usable knowledge. This new type of knowledge can serve as a basis for decision making. This inclusive approach encourages all parties to take ownership in the process and solutions, thereby causing them to be more likely to act on the problem, both at the systemic, policy-driven level, and at the individual level by cooperatively supporting the associated structural and lifestyle developments. For the presentation of the results, we will focus on experiences from joint projects with non-governmental organizations on city authorities.

  15. The shape gradient of the least-squares objective functional in optimal shape design problems of radiative heat transfer

    International Nuclear Information System (INIS)

    Rukolaine, Sergey A.

    2010-01-01

    Optimal shape design problems of steady-state radiative heat transfer are considered. The optimal shape design problem (in the three-dimensional space) is formulated as an inverse one, i.e., in the form of an operator equation of the first kind with respect to a surface to be optimized. The operator equation is reduced to a minimization problem via a least-squares objective functional. The minimization problem has to be solved numerically. Gradient minimization methods need the gradient of a functional to be minimized. In this paper the shape gradient of the least-squares objective functional is derived with the help of the shape sensitivity analysis and adjoint problem method. In practice a surface to be optimized may be (or, most likely, is to be) given in a parametric form by a finite number of parameters. In this case the objective functional is, in fact, a function in a finite-dimensional space and the shape gradient becomes an ordinary gradient. The gradient of the objective functional, in the case that the surface to be optimized is given in a finite-parametric form, is derived from the shape gradient. A particular case, that a surface to be optimized is a 'two-dimensional' polyhedral one, is considered. The technique, developed in the paper, is applied to a synthetic problem of designing a 'two-dimensional' radiant enclosure.

  16. Application of the BRF system to some superconducting magnet design problems

    International Nuclear Information System (INIS)

    Meuser, R.B.

    1974-01-01

    The Berkeley Remote Facility (BRF) system--affected through a system of teletype terminals linked to the LBL computers--was used to solve a large number of magnetic-field problems associated with the design and analysis of superconducting beam-transport magnets. The limitations of the BRF system are severe: total storage, 1000; 10 subscripted variables; no integer or complex arithmetic; no function or subroutine subprograms except those in its Spartan library; and a pidgin Fortran language. However, for fully 90 percent of the computational work, the low IQ of the BRF was more than counter-balanced by its being on-line. The magnets built have a long cylindrical aperture surrounded by arrays of longitudinal superconducting wires and iron arranged to produce a transverse field of prescribed shape, uniform fields for bending high energy charged particle beams, and quarupole fields for focusing. The field in the aperture is expressed, usually, in terms of the coefficients of the Taylor's expansion--the ''multipole coefficients''. Point values of the field vector are also of interest, especially within the windings, as the magnitude of the field determines the allowable current. Many small programs were developed to analyze both the two- and three-dimensional fields produced by various kinds of arrays of conductors. Some programs have the ability to vary a number of geometric parameters automatically in such a way as to drive the same number of multipole coefficients to zero. The on-line feature is especially handy, as such iterative calculations must often be cajoled into convergence. (U.S.)

  17. Combinatorial instruments in the design of a heuristic for the quadratic assignment problem

    Directory of Open Access Journals (Sweden)

    Paulo Oswaldo Boaventura-Netto

    2003-12-01

    Full Text Available This work discusses the use of a neighbouring structure in the design of specific heuristics for the Quadratic Assignment Problem (QAP. This structure is formed by the 4- and 6-cycles adjacent to a vertex in the Hasse diagram of the permutation lattice and it can be adequately partitioned in subsets of linear and quadratic cardinalities, a characteristics which frequently allows an economy in the processing time. We propose also a restart strategy and a mechanism for generating initial solutions which constitute, together with the neighbouring structure, a possible QAP-specific heuristic proposal. For the construction of these instruments we used the relaxed ordered set of QAP solutions.Este trabalho discute o uso de uma estrutura de vizinhança em heurísticas específicas para o Problema Quadrático de Alocação (PQA. Esta estrutura envolve os ciclos de comprimento 4 e 6 adjacentes a um vértice do diagrama de Hasse do reticulado das permutações e pode ser particionada em subconjuntos de cardinalidade linear e quadrática em relação à ordem da instância, o que permite frequentemente uma economia de tempo de processamento. Propõem-se ainda uma estratégia de repartida e um mecanismo de geração de soluções iniciais, que constituem, ao lado da estrutura de vizinhança, uma proposta de heurística específica para o PQA. Na construção desses instrumentos foi utilizada a noção de conjunto relaxado ordenado das soluções do PQA.

  18. Design Thinking: A Methodology towards Sustainable Problem Solving in Higher Education in South Africa

    Science.gov (United States)

    Munyai, Keneilwe

    2016-01-01

    This short paper explores the potential contribution of design thinking methodology to the education and training system in South Africa. Design thinking is slowly gaining traction in South Africa. Design Thinking is gaining traction in South Africa. There is offered by the Hasso Plattner Institute of Design Thinking at the University of Cape Town…

  19. A Course on Serious Game Design and Development Using an Online Problem-Based Learning Approach

    Science.gov (United States)

    Kapralos, Bill; Fisher, Stephanie; Clarkson, Jessica; van Oostveen, Roland

    2015-01-01

    Purpose: The purpose of this paper is to describe a novel undergraduate course on serious game design and development that integrates both game and instructional design, thus providing an effective approach to teaching serious game design and development. Very little effort has been dedicated to the teaching of proper serious game design and…

  20. Using Problem Based Learning and Game Design to motivate Non-technical Students to engage in Technical Learning

    DEFF Research Database (Denmark)

    Reng, Lars; Schoenau-Fog, Henrik

    2010-01-01

    of Medialogy, we employ problem based learning and game design to engage these students in learning the technical elements. This paper will describe our approach and exemplify the method by introducing various examples of student projects, where the interest in game design combined with problem based learning...... technology, a broader segment of students are consequently enrolled. One of the challenges of these new educations is to motivate the artistic minded students in learning the technical aspects of the curriculum, as they need these qualifications to work in the industry. At Aalborg University’s department...... have engaged and motivated artistic students to learn technical topics on their own....

  1. Guaranteed roll-off in a class of high-gain feedback design problems

    NARCIS (Netherlands)

    Trentelman, Hendrikus; Willems, Jan C.

    1983-01-01

    A number of synthesis problems associated with (almost) disturbance decoupling by state or measurement feedback is considered. Starting from a mathematical definition of the notion of high-frequency roll-off, known results on the solvability of these problems are generalized to the situation in

  2. Development and Design of Problem Based Learning Game-Based Courseware

    Science.gov (United States)

    Chang, Chiung-Sui; Chen, Jui-Fa; Chen, Fei-Ling

    2015-01-01

    In an educational environment, instructors would always think of ways to provide students with motivational learning materials and efficient learning strategies. Hence, many researchers have proposed that students' problem-solving ability enhances their learning. Problem-solving ability plays an important role for users in dealing with problems…

  3. Students Advise Fortune 500 Company: Designing a Problem-Based Learning Community

    Science.gov (United States)

    Brzovic, Kathy; Matz, S. Irene

    2009-01-01

    This article describes the process of planning and implementing a problem-based learning community. Business and communication students from a large university in the Western United States competed in teams to solve an authentic business problem posed by a Fortune 500 company. The company's willingness to adopt some of their recommendations…

  4. Integration of the Response Surface Methodology with the Compromise Decision Support Problem in Developing a General Robust Design Procedure

    Science.gov (United States)

    Chen, Wei; Tsui, Kwok-Leung; Allen, Janet K.; Mistree, Farrokh

    1994-01-01

    In this paper we introduce a comprehensive and rigorous robust design procedure to overcome some limitations of the current approaches. A comprehensive approach is general enough to model the two major types of robust design applications, namely, robust design associated with the minimization of the deviation of performance caused by the deviation of noise factors (uncontrollable parameters), and robust design due to the minimization of the deviation of performance caused by the deviation of control factors (design variables). We achieve mathematical rigor by using, as a foundation, principles from the design of experiments and optimization. Specifically, we integrate the Response Surface Method (RSM) with the compromise Decision Support Problem (DSP). Our approach is especially useful for design problems where there are no closed-form solutions and system performance is computationally expensive to evaluate. The design of a solar powered irrigation system is used as an example. Our focus in this paper is on illustrating our approach rather than on the results per se.

  5. Ontology Design for Solving Computationally-Intensive Problems on Heterogeneous Architectures

    Directory of Open Access Journals (Sweden)

    Hossam M. Faheem

    2018-02-01

    Full Text Available Viewing a computationally-intensive problem as a self-contained challenge with its own hardware, software and scheduling strategies is an approach that should be investigated. We might suggest assigning heterogeneous hardware architectures to solve a problem, while parallel computing paradigms may play an important role in writing efficient code to solve the problem; moreover, the scheduling strategies may be examined as a possible solution. Depending on the problem complexity, finding the best possible solution using an integrated infrastructure of hardware, software and scheduling strategy can be a complex job. Developing and using ontologies and reasoning techniques play a significant role in reducing the complexity of identifying the components of such integrated infrastructures. Undertaking reasoning and inferencing regarding the domain concepts can help to find the best possible solution through a combination of hardware, software and scheduling strategies. In this paper, we present an ontology and show how we can use it to solve computationally-intensive problems from various domains. As a potential use for the idea, we present examples from the bioinformatics domain. Validation by using problems from the Elastic Optical Network domain has demonstrated the flexibility of the suggested ontology and its suitability for use with any other computationally-intensive problem domain.

  6. Hierarchical Thinking: A Cognitive Tool for Guiding Coherent Decision Making in Design Problem Solving

    Science.gov (United States)

    Haupt, Grietjie

    2018-01-01

    This paper builds on two concepts, the first of which is the extended information processing model of expert design cognition. This proposes twelve internal psychological characteristics interacting with the external world of expert designers during the early phases of the design process. Here, I explore one of the characteristics, hierarchical…

  7. High School Students' Written Argumentation Qualities with Problem-Based Computer-Aided Material (PBCAM) Designed about Human Endocrine System

    Science.gov (United States)

    Vekli, Gülsah Sezen; Çimer, Atilla

    2017-01-01

    This study investigated development of students' scientific argumentation levels in the applications made with Problem-Based Computer-Aided Material (PBCAM) designed about Human Endocrine System. The case study method was used: The study group was formed of 43 students in the 11th grade of the science high school in Rize. Human Endocrine System…

  8. Solving Real World Problems with Alternate Reality Gaming: Student Experiences in the Global Village Playground Capstone Course Design

    Science.gov (United States)

    Dondlinger, Mary Jo; McLeod, Julie K.

    2015-01-01

    The Global Village Playground (GVP) was a capstone learning experience designed to address institutional assessment needs while providing an integrated and authentic learning experience for students aimed at fostering complex problem solving, as well as critical and creative thinking. In the GVP, students work on simulated and real-world problems…

  9. Achieving consensus in robot swarms design and analysis of strategies for the best-of-n problem

    CERN Document Server

    Valentini, Gabriele

    2017-01-01

    This book focuses on the design and analysis of collective decision-making strategies for the best-of-n problem. After providing a formalization of the structure of the best-of-n problem supported by a comprehensive survey of the swarm robotics literature, it introduces the functioning of a collective decision-making strategy and identifies a set of mechanisms that are essential for a strategy to solve the best-of-n problem. The best-of-n problem is an abstraction that captures the frequent requirement of a robot swarm to choose one option from of a finite set when optimizing benefits and costs. The book leverages the identification of these mechanisms to develop a modular and model-driven methodology to design collective decision-making strategies and to analyze their performance at different level of abstractions. Lastly, the author provides a series of case studies in which the proposed methodology is used to design different strategies, using robot experiments to show how the designed strategies can b...

  10. Topological Design for Acoustic-Structure Interaction Problems with a Mixed Finite Element Method

    DEFF Research Database (Denmark)

    Yoon, Gil Ho; Jensen, Jakob Søndergaard; Sigmund, Ole

    2006-01-01

    We propose a gradient based topology optimization algorithm for acoustic-structure (Vibro-acoustic) interaction problems without an explicit interfacing boundary representation. In acoustic-structure interaction problems, the pressure field and the displacement field are governed by the Helmholtz...... to subdomain interfaces evolving during the optimization process. In this paper, we propose to use a mixed finite element formulation with displacements and pressure as primary variables (u/p formulation) which eliminates the need for explicit boundary representation. In order to describe the Helmholtz...... acoustic-structure interaction problems are optimized to show the validity of the proposed method....

  11. Design and Usability Assessment of a Dialogue-Based Cognitive Tutoring System to Model Expert Problem Solving in Research Design

    Science.gov (United States)

    Hung, Wei-Chen; Smith, Thomas J.; Smith, M. Cecil

    2015-01-01

    Technology provides the means to create useful learning and practice environments for learners. Well-designed cognitive tutor systems, for example, can provide appropriate learning environments that feature cognitive supports (ie, scaffolding) for students to increase their procedural knowledge. The purpose of this study was to conduct a series of…

  12. Soft Computing Methods for Microwave and Millimeter-Wave Design Problems

    CERN Document Server

    Chauhan, Narendra; Mittal, Ankush

    2012-01-01

    The growing commercial market of Microwave/ Millimeter wave industry over the past decade has led to the explosion of interests and opportunities for the design and development of microwave components.The design of most microwave components requires the use of commercially available electromagnetic (EM) simulation tools for their analysis. In the design process, the simulations are carried out by varying the design parameters until the desired response is obtained. The optimization of design parameters by manual searching is a cumbersome and time consuming process. Soft computing methods such as Genetic Algorithm (GA), Artificial Neural Network (ANN) and Fuzzy Logic (FL) have been widely used by EM researchers for microwave design since last decade. The aim of these methods is to tolerate imprecision, uncertainty, and approximation to achieve robust and low cost solution in a small time frame.  Modeling and optimization are essential parts and powerful tools for the microwave/millimeter wave design. This boo...

  13. Engineering design of an environmental management system: A transdisciplinary response to the rhino poaching problem

    CSIR Research Space (South Africa)

    Roodt, H

    2014-10-01

    Full Text Available principles to address the wicked problems through appropriate research (analytical) methods that transcends disciplinary focussed solution finding. To highlight the proposed approach the development of an environmental management system as a response...

  14. A dimension decomposition approach based on iterative observer design for an elliptic Cauchy problem

    KAUST Repository

    Majeed, Muhammad Usman

    2015-07-13

    A state observer inspired iterative algorithm is presented to solve boundary estimation problem for Laplace equation using one of the space variables as a time-like variable. Three dimensional domain with two congruent parallel surfaces is considered. Problem is set up in cartesian co-ordinates and Laplace equation is re-written as a first order state equation with state operator matrix A and measurements are provided on the Cauchy data surface with measurement operator C. Conditions for the existence of strongly continuous semigroup generated by A are studied. Observability conditions for pair (C, A) are provided in infinite dimensional setting. In this given setting, special observability result obtained allows to decompose three dimensional problem into a set of independent two dimensional sub-problems over rectangular cross-sections. Numerical simulation results are provided.

  15. Survey of editors and reviewers of high-impact psychology journals: statistical and research design problems in submitted manuscripts.

    Science.gov (United States)

    Harris, Alex; Reeder, Rachelle; Hyun, Jenny

    2011-01-01

    The authors surveyed 21 editors and reviewers from major psychology journals to identify and describe the statistical and design errors they encounter most often and to get their advice regarding prevention of these problems. Content analysis of the text responses revealed themes in 3 major areas: (a) problems with research design and reporting (e.g., lack of an a priori power analysis, lack of congruence between research questions and study design/analysis, failure to adequately describe statistical procedures); (b) inappropriate data analysis (e.g., improper use of analysis of variance, too many statistical tests without adjustments, inadequate strategy for addressing missing data); and (c) misinterpretation of results. If researchers attended to these common methodological and analytic issues, the scientific quality of manuscripts submitted to high-impact psychology journals might be significantly improved.

  16. The multi-objective network design problem using minimizing externalities as objectives: comparison of a genetic algorithm and simulated annealing framework.

    NARCIS (Netherlands)

    Possel, B.; Wismans, Luc Johannes Josephus; van Berkum, Eric C.; Bliemer, M.C.J.

    2016-01-01

    Incorporation of externalities in the Multi-Objective Network Design Problem (MO NDP) as objectives is an important step in designing sustainable networks. In this research the problem is defined as a bi-level optimization problem in which minimizing externalities are the objectives and link types

  17. Development of a Preventive HIV Vaccine Requires Solving Inverse Problems Which Is Unattainable by Rational Vaccine Design

    Directory of Open Access Journals (Sweden)

    Marc H. V. Van Regenmortel

    2018-01-01

    Full Text Available Hypotheses and theories are essential constituents of the scientific method. Many vaccinologists are unaware that the problems they try to solve are mostly inverse problems that consist in imagining what could bring about a desired outcome. An inverse problem starts with the result and tries to guess what are the multiple causes that could have produced it. Compared to the usual direct scientific problems that start with the causes and derive or calculate the results using deductive reasoning and known mechanisms, solving an inverse problem uses a less reliable inductive approach and requires the development of a theoretical model that may have different solutions or none at all. Unsuccessful attempts to solve inverse problems in HIV vaccinology by reductionist methods, systems biology and structure-based reverse vaccinology are described. The popular strategy known as rational vaccine design is unable to solve the multiple inverse problems faced by HIV vaccine developers. The term “rational” is derived from “rational drug design” which uses the 3D structure of a biological target for designing molecules that will selectively bind to it and inhibit its biological activity. In vaccine design, however, the word “rational” simply means that the investigator is concentrating on parts of the system for which molecular information is available. The economist and Nobel laureate Herbert Simon introduced the concept of “bounded rationality” to explain why the complexity of the world economic system makes it impossible, for instance, to predict an event like the financial crash of 2007–2008. Humans always operate under unavoidable constraints such as insufficient information, a limited capacity to process huge amounts of data and a limited amount of time available to reach a decision. Such limitations always prevent us from achieving the complete understanding and optimization of a complex system that would be needed to achieve a truly

  18. Design of a Maglev Vibration Test Platform for the Research of Maglev Vehicle-girder Coupled Vibration Problem

    Directory of Open Access Journals (Sweden)

    Zhou Danfeng

    2017-01-01

    Full Text Available The maglev vehicle-girder coupled vibration problem has been encountered in many maglev test or commercial lines, which significantly degrade the performance of the maglev train. In previous research on the principle of the coupled vibration problem, it has been discovered that the fundamental model of the maglev girder can be simplified as a series of mass-spring resonators of different but related resonance frequencies, and that the stability of the vehicle-girder coupled system can be investigated by separately examining the stability of each mass-spring resonator – electromagnet coupled system. Based on this conclusion, a maglev test platform, which includes a single electromagnetic suspension control system, is built for experimental study of the coupled vibration problem. The guideway of the test platform is supported by a number of springs so as to change its flexibility. The mass of the guideway can also be changed by adjusting extra weights attached to it. By changing the flexibility and mass of the guideway, the rules of the maglev vehicle-girder coupled vibration problem are to be examined through experiments, and related theory on the vehicle-girder self-excited vibration proposed in previous research is also testified.

  19. Treatment rationale and study design for a randomized, double-blind, placebo-controlled phase II study evaluating onartuzumab (MetMAb) in combination with bevacizumab plus mFOLFOX-6 in patients with previously untreated metastatic colorectal cancer.

    Science.gov (United States)

    Bendell, Johanna C; Ervin, Thomas J; Gallinson, David; Singh, Jaswinder; Wallace, James A; Saleh, Mansoor N; Vallone, Marcy; Phan, See-Chun; Hack, Stephen P

    2013-09-01

    Dysregulation of the hepatocyte growth factor (HGF)/MET pathway is associated with poor prognosis, more aggressive biological characteristics of the tumor, and shortened survival in patients with metastatic colorectal cancer (mCRC). Onartuzumab (MetMAb) is a recombinant humanized monovalent monoclonal antibody directed against MET. We present the treatment rationale and protocol for an ongoing randomized multicenter placebo-controlled phase II study designed to evaluate the efficacy and safety of MetMAb combined with bevacizumab and mFOLFOX-6 (5-fluoruracil, leucovorin, and oxaliplatin). Eligible patients with previously untreated mCRC are randomized 1:1 to either mFOLFOX-6 combined with bevacizumab and placebo followed by 5-fluorouracil/leucovorin plus bevacizumab and placebo or mFOLFOX6, bevacizumab plus MetMAb followed by 5 FU/LV, bevacizumab, and MetMAb. The primary end point of this study is progression-free survival (PFS) in the intent-to-treat (ITT) population. Secondary end points include overall survival (OS), objective response rate, and safety. Subanalyses will be performed to evaluate the effect of MET receptor expression on study primary and secondary end points. Correlative studies will be performed on tissue- and blood-derived biomarkers related to both HGF/MET signaling and other associated pathway markers. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Robustness and efficiency of D-optimal experimental designs in a growth problem

    NARCIS (Netherlands)

    Paulo, M.J.; Rasch, D.

    2002-01-01

    To assess tree growth, for example in diameter, a forester typically measures the trees at regular time points. We call such designs equidistant. In this paper we look at the robustness and efficiency of several experimental designs, using the D-optimality criterion, in a case study of diameter

  1. Letting the Learner Learn--Interface Design that Promotes Learning--Problems and Solutions at UPS.

    Science.gov (United States)

    Swiader, Lawrence; And Others

    1996-01-01

    Discussion of interactive, multimedia instructional material development and the development of computer-based training focuses on experiences at UPS (United Parcel Service). Topics include opening screen design; log-on screens; main menus; and lesson design, including color, sound, graphics and video, icons, and directions and instruction…

  2. Problems in problem analysis

    DEFF Research Database (Denmark)

    Almegaard, Henrik

    2014-01-01

    The majority of literature on engineering design methods is focused on the processes of fulfilling the design goals as efficiently as possible. This paper will focus on - and discuss - the processes of determining the design goals: the specifications. The purpose is to draw attention to the inher...... to the inherent problems, dilemmas and possibilities in these processes bearing in mind that that the most important decisions in a design project are taken in the beginning of the project....

  3. A Benders Decomposition-Based Matheuristic for the Cardinality Constrained Shift Design Problem

    DEFF Research Database (Denmark)

    Lusby, Richard Martin; Range, Troels Martin; Larsen, Jesper

    2016-01-01

    is bounded by an upper limit. We present an integer programming model for this problem and show that its structure lends itself very naturally to Benders decomposition. Due to convergence issues with a conventional implementation, we propose a matheuristic based on Benders decomposition for solving...... integer programming solver on instances with 1241 different shift types and remains competitive for larger cases with 2145 shift types. On all classes of problems the heuristic is able to quickly find good solutions. © 2016 Elsevier B.V. All rights reserved...

  4. Validations of BWR nuclear design code using ABWR MOX numerical benchmark problems

    International Nuclear Information System (INIS)

    Takano, Shou; Sasagawa, Masaru; Yamana, Teppei; Ikehara, Tadashi; Yanagisawa, Naoki

    2017-01-01

    BWR core design code package (the HINES assembly code and the PANACH core simulator), being used for full MOX-ABWR core design, has been benchmarked against the high-fidelity numerical solutions as references, for the purpose of validating its capability of predicting the BWR core design parameters systematically from UO 2 to 100% MOX cores. The reference solutions were created by whole core critical calculations using MCNPs with the precisely modeled ABWR cores both in hot and cold conditions at BOC and EOC of the equilibrium cycle. A Doppler-Broadening Rejection Correction (DCRB) implemented MCNP5-1.4 with ENDF/B-VII.0 was mainly used to evaluate the core design parameters, except for effective delayed neutron fraction (β eff ) and prompt neutron lifetime (l) with MCNP6.1. The discrepancies in the results between the design codes HINES-PANACH and MCNPs for the core design parameters such as the bundle powers, hot pin powers, control rod worth, boron worth, void reactivity, Doppler reactivity, β eff and l, are almost within target accuracy, leading to the conclusion that HINES-PANACH has sufficient fidelity for application to full MOX-ABWR core design. (author)

  5. Priorities in urban traffic problems and implications for the design of solutions

    NARCIS (Netherlands)

    Vreeswijk, Jacob Dirk; van Berkum, Eric C.; van Arem, Bart; ITS,

    2011-01-01

    The introduction of ICT in the traffic domain showed great potential, but the many opportunities this brings seems to have distracted engineers. To solve urban traffic problems, many potentially effective solutions have been developed, but deployment rates are low. The main reason seems to be that

  6. Computer Problem-Solving Coaches for Introductory Physics: Design and Usability Studies

    Science.gov (United States)

    Ryan, Qing X.; Frodermann, Evan; Heller, Kenneth; Hsu, Leonardo; Mason, Andrew

    2016-01-01

    The combination of modern computing power, the interactivity of web applications, and the flexibility of object-oriented programming may finally be sufficient to create computer coaches that can help students develop metacognitive problem-solving skills, an important competence in our rapidly changing technological society. However, no matter how…

  7. Engineering-Based Problem Solving in the Middle School: Design and Construction with Simple Machines

    Science.gov (United States)

    English, Lyn D.; Hudson, Peter; Dawes, Les

    2013-01-01

    Incorporating engineering concepts into middle school curriculum is seen as an effective way to improve students' problem-solving skills. A selection of findings is reported from a science, technology, engineering and mathematics (STEM)-based unit in which students in the second year (grade 8) of a three-year longitudinal study explored…

  8. How to design fiber optic sensors that work: basic technology, main problems, pitfalls, and potential solutions

    OpenAIRE

    Dakin, J.P.

    1999-01-01

    Summary• Overview of optical fibre sensor types(Classified according to operating principles)• Difference between intrinsic and extrinsic sensors• Intensity-based sensors• Spectrally-encoded sensors• Propagation-time-encoded sensors• Interferometric sensors• Discussion of how to avoid problems and make practical sensors• Multiplexed and distributed sensors

  9. Information problem solving instruction in higher education: A case study on instructional design

    NARCIS (Netherlands)

    Wopereis, Iwan; Frerejean, Jimmy; Brand-Gruwel, Saskia

    2015-01-01

    Information problem solving (IPS) is the process of locating, selecting, evaluating, and integrating information from various sources to fulfill an information need. In academia, it is central to conducting literature reviews in research projects. This paper presents a case study on effective and

  10. Alternative Fuels and Hybrid Technology: A Classroom Activity Designed to Evaluate a Contemporary Problem

    Science.gov (United States)

    Roy MacArthur, Amy H.; Copper, Christine L.

    2009-01-01

    As petroleum reserves are being depleted worldwide and energy costs are increasing, the use of alternative fuels is being more widely considered as a solution to the impending energy crisis. In this classroom activity students are presented with a real-world problem in which they must evaluate the properties and environmental impacts of a variety…

  11. Design, Implementation, and Evaluation of a Tutor Training for Problem Based Learning in Undergraduate Psychology Courses

    Science.gov (United States)

    Mühlfelder, Manfred; Konermann, Tobias; Borchard, Linda-Marie

    2015-01-01

    In this paper we describe a "Train the Tutor" programme (TtT) for developing the metacognitive skills, facilitator skills, and tutor skills of students in a problem based learning (PBL) context. The purpose of the programme was to train 2nd and 3rd year undergraduate students in psychology to become effective PBL tutors for…

  12. Genetic Algorithm for Multiuser Discrete Network Design Problem under Demand Uncertainty

    Directory of Open Access Journals (Sweden)

    Wu Juan

    2012-01-01

    Full Text Available Discrete network design is an important part of urban transportation planning. The purpose of this paper is to present a bilevel model for discrete network design. The upper-level model aims to minimize the total travel time under a stochastic demand to design a discrete network. In the lower-level model, demands are assigned to the network through a multiuser traffic equilibrium assignment. Generally, discrete network could affect path selections of demands, while the results of the multiuser traffic equilibrium assignment need to reconstruct a new discrete network. An iterative approach including an improved genetic algorithm and Frank-Wolfe algorithm is used to solve the bi-level model. The numerical results on Nguyen Dupuis network show that the model and the related algorithms were effective for discrete network design.

  13. PROBLEMS OF DESIGN AND CONSTRUCTION OF UNDERGROUND AND TRANSPORT FACILITIES IN THE CONDITIONS OF BELARUS

    Directory of Open Access Journals (Sweden)

    V. A. Sernov

    2010-03-01

    Full Text Available The experience of design and erecting of underground and transport structures, fencing deep excavations in cramped urban conditions on the examples of various projects in the Republic of Belarusis presented in the paper.

  14. The air transportation hub-and-spoke design problem: comparison between a continuous and a discrete solution method

    Directory of Open Access Journals (Sweden)

    Guina Sotomayor Alzamora

    2013-12-01

    Full Text Available The hub-and-spoke network design problem, also known as the hub location problem, aims to find the concentration points in a given network flow so that the sum of the distances of the linkages is minimized. In this work, we compare discrete solutions of this problem, given by the branch-and-cut method applied to the p-hub median model, with continuous solutions, given by the hyperbolic smoothing technique applied to a min-sum-min model. Computational experiments for particular instances of the Brazilian air transportation system, with the number of hubs varying from 2 to 8, are conducted with the support of a discretization heuristic and the Voronoi diagram.

  15. A Biobjective and Trilevel Programming Model for Hub Location Problem in Design of a Resilient Power Projection Network

    Directory of Open Access Journals (Sweden)

    Hai-Ling Bi

    2016-01-01

    Full Text Available Hubs disruptions are taken into account in design of a resilient power projection network. The problem is tackled from a multiple criteria decision-making (MCDM perspective. Not only the network cost in normal state is considered, but also the cost in the worst-case situation is taken into account. A biobjective and trilevel integer programming model is proposed using game theory. Moreover, we develop a metaheuristic based on tabu search and shortest path algorithm for the resolution of the complex model. Computational example indicates that making tradeoffs between the performances of the network in different situations is helpful for designing a resilient network.

  16. Problem based Learning versus Design Thinking in Team based Project work

    DEFF Research Database (Denmark)

    Denise J. Stokholm, Marianne

    2014-01-01

    the PBL to update the educations to meet today’s competitive global society. In order to create an informed basis for discussing and updating the historic approach to project work at Aalborg University, this paper will try to unfold and compare PBL and DBL and the competences they create through team...... project based learning issues, which has caused a need to describe and compare the two models; in specific the understandings, approaches and organization of learning in project work. The PBL model viewing the process as 3 separate project stages including; problem analysis, problem solving and project...... based project work. The paper will exemplify how projects work is organized, supervised, staged and reported. It will investigate the practical organization of the teamwork and process as well as the dominating mindsets and methods used during the process. Comparing the two models concerning...

  17. Effectiveness and cost-effectiveness of an educational intervention for practice teams to deliver problem focused therapy for insomnia: rationale and design of a pilot cluster randomised trial

    Directory of Open Access Journals (Sweden)

    Ørner Roderick

    2009-01-01

    Full Text Available Abstract Background Sleep problems are common, affecting over a third of adults in the United Kingdom and leading to reduced productivity and impaired health-related quality of life. Many of those whose lives are affected seek medical help from primary care. Drug treatment is ineffective long term. Psychological methods for managing sleep problems, including cognitive behavioural therapy for insomnia (CBTi have been shown to be effective and cost effective but have not been widely implemented or evaluated in a general practice setting where they are most likely to be needed and most appropriately delivered. This paper outlines the protocol for a pilot study designed to evaluate the effectiveness and cost-effectiveness of an educational intervention for general practitioners, primary care nurses and other members of the primary care team to deliver problem focused therapy to adult patients presenting with sleep problems due to lifestyle causes, pain or mild to moderate depression or anxiety. Methods and design This will be a pilot cluster randomised controlled trial of a complex intervention. General practices will be randomised to an educational intervention for problem focused therapy which includes a consultation approach comprising careful assessment (using assessment of secondary causes, sleep diaries and severity and use of modified CBTi for insomnia in the consultation compared with usual care (general advice on sleep hygiene and pharmacotherapy with hypnotic drugs. Clinicians randomised to the intervention will receive an educational intervention (2 × 2 hours to implement a complex intervention of problem focused therapy. Clinicians randomised to the control group will receive reinforcement of usual care with sleep hygiene advice. Outcomes will be assessed via self-completion questionnaires and telephone interviews of patients and staff as well as clinical records for interventions and prescribing. Discussion Previous studies in adults

  18. Dimensioning and design rules for sliding bearings; optimisation problems; Bemessungs- und Gestaltungsregeln fuer Gleitlager: Optimierungsfragen

    Energy Technology Data Exchange (ETDEWEB)

    Spiegel, K. [Fachhochschule Duesseldorf (Germany); Fricke, J.

    2000-07-01

    Already in the design stage of sliding bearings, optimal conditions for operation at a later stage should be envisaged. The contribution presents hints for optimal design and calculation of radial and axial bearings, e.g. gap design, optimised supporting strength, friction loss and lubricant throughput, lubricant exchange and lubricant heat exchange, and improved control of internal lubricant flow. [German] Bei der Auslegung von Gleitlagern ist es von Interesse, moeglichst optimale Bedingungen fuer den spaeteren Betrieb zu schaffen. Im vorliegenden Beitrag werden einige bereits bekannte und auch neue Hinweise zur optimalen Gestaltung und Berechnung, sowohl fuer Radial- als auch Axiallager gegeben. Dies betreffen im wesentlichen: die Gestaltung des Spaltverlaufs, Empfehlungen zur Optimierung der Tragfaehigkeit, der Reibungsverluste und des Schmierstoffdurchsatzes, Hinweise zum Schmierstoff- bzw. Schmierstoff-Waermeaustausch und die Verbesserung der inneren Schmierstofffuehrung. (orig.)

  19. Problems in the design of a proton driver for a {mu}-{mu} collider

    Energy Technology Data Exchange (ETDEWEB)

    Mils, F.E.

    1996-09-01

    Design details are given for accelerator physics issues, technical components and final beam bunching. Discussed physics issues include: space charge tune shift, microwave instability of bunched beam, transverse resistive wall instability, head-tail instability, cavity beam loading, and lattice design. The use of technical components to minimize beam impedance is investigated. Several alternatives to the ISIS-type wire of rod cage were considered: vacuum, magnets, rf cavities, and injection. The two final beam bunching schemes considered were: chicane and an assembler ring with linear induction buncher.

  20. Single Phase Current-Source Active Rectifier for Traction: Control System Design and Practical Problems

    Directory of Open Access Journals (Sweden)

    Jan Michalik

    2006-01-01

    Full Text Available This research has been motivated by industrial demand for single phase current-source active rectifier dedicated for reconstruction of older types of dc machine locomotives. This paper presents converters control structure design and simulations. The proposed converter control is based on the mathematical model and due to possible interaction with railway signaling and required low switching frequency employs synchronous PWM. The simulation results are verified by experimental tests performed on designed laboratory prototype of power of 7kVA

  1. Resilience design: toward a synthesis of cognition, learning, and collaboration for adaptive problem solving in conservation and natural resource stewardship

    Directory of Open Access Journals (Sweden)

    Charles G. Curtin

    2014-06-01

    Full Text Available Through the resilience design approach, I propose to extend the resilience paradigm by re-examining the components of adaptive decision-making and governance processes. The approach can be divided into three core components: (1 equity design, i.e., the integration of collaborative approaches to conservation and adaptive governance that generates effective self-organization and emergence in conservation and natural resource stewardship; (2 process design, i.e., the generation of more effective knowledge through strategic development of information inputs; and (3 outcome design, i.e., the pragmatic synthesis of the previous two approaches, generating a framework for developing durable and dynamic conservation and stewardship. The design of processes that incorporate perception and learning is critical to generating durable solutions, especially in developing linkages between wicked social and ecological challenges. Starting from first principles based on human cognition, learning, and collaboration, coupled with nearly two decades of practical experience designing and implementing ecosystem-level conservation and restoration programs, I present how design-based approaches to conservation and stewardship can be achieved. This context is critical in helping practitioners and resources managers undertake more effective policy and practice.

  2. Insights from a Financial Literacy Task Designer: The Curious Case of Problem Context

    Science.gov (United States)

    Sawatzki, Carly

    2016-01-01

    As part of ongoing design-based research exploring financial literacy teaching and learning, ten tasks termed "financial dilemmas" were trialled by 14 teachers and more than 300 Year 5 and 6 students in 4 government primary schools in urban Darwin. Drawing on data related to two tasks--"Catching the bus" and "Buying…

  3. Problem Scoping Design Thinking and Close Reading: Makerspaces in the School Library

    Science.gov (United States)

    Blakemore, Megan

    2018-01-01

    Makerspaces, collaborative workspaces stocked with materials and tools for creating, building, designing, and learning, are becoming more and more common in schools and, in particular, in school libraries. Makerspaces in the school library allow for connections between making and literacy. Indeed, such connections are authentic and natural as…

  4. Grade 3 Learners' Representation of Their Solutions to a Design Problem through Drawing: A Semiotic Analysis

    Science.gov (United States)

    Alant, Busisiwe P.; Sherwood, Marion P.

    2017-01-01

    Literature suggests that drawing has an important role in the development of learning and thinking skills and the communication of ideas. However, the role and use of drawing by young learners within the process of designing is poorly understood. Working with 22 Grade 3 learners from a well-resourced school in KwaZulu-Natal, this study sought to…

  5. The Linearized Simultaneous String-Design and Cargo-Routing Problem

    DEFF Research Database (Denmark)

    Plum, Christian Edinger Munk

    A global liner shipping network, consists of a billion dollar investment in assets. Designing this network, to minimize costs, while considering operational constraints is thus of great relevance. Empirical studies of the cost structure of a networks strings (ship rotations), show linear relation...

  6. On the observer design problem for continuous-time switched linear systems with unknown switchings

    Czech Academy of Sciences Publication Activity Database

    Gómez–Gutiérrez, D.; Čelikovský, Sergej; Ramírez–Trevino, A.; Castillo-Toledo, B.

    2015-01-01

    Roč. 352, č. 4 (2015), s. 1595-1612 ISSN 0016-0032 R&D Projects: GA ČR GA13-20433S Institutional support: RVO:67985556 Keywords : observer design * switched systems Subject RIV: BC - Control Systems Theory Impact factor: 2.327, year: 2015 http://library.utia.cas.cz/separaty/2015/TR/celikovsky-0442959.pdf

  7. A greedy construction heuristic for the liner service network design problem

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard

    is challenging due to the size of a global liner shipping operation and due to the hub-and-spoke network design, where a high percentage of the total cargo is transshipped. We present the first construction heuristic for large scale instances of the LSN-DP. The heuristic is able to find a solution for a real...

  8. On designing geometric motion planners to solve regulating and trajectory tracking problems for robotic locomotion systems

    Energy Technology Data Exchange (ETDEWEB)

    Asnafi, Alireza [Hydro-Aeronautical Research Center, Shiraz University, Shiraz, 71348-13668 (Iran, Islamic Republic of); Mahzoon, Mojtaba, E-mail: asnafi@shirazu.ac.ir, E-mail: arasnafi@yahoo.com, E-mail: mahzoon@shirazu.ac.ir [Department of Mechanical Engineering, School of Engineering, Shiraz University, Shiraz, 71348-13668 (Iran, Islamic Republic of)

    2011-09-15

    Based on a geometric fiber bundle structure, a generalized method to solve both regulation and trajectory tracking problems for locomotion systems is presented. The method is especially applied to two case studies of robotic locomotion systems; a three link articulated fish-like robot as a prototype of locomotion systems with symmetry, and the snakeboard as a prototype of mixed locomotion systems. Our results show that although these motion planners have an open loop structure, due to their generalities, they can steer case studies with negligible errors for almost any complicated path.

  9. A novel deployment design of vena cava filters might be the solution to their blockage problem.

    Science.gov (United States)

    Chen, Zengsheng; Fan, Yubo; Deng, Xiaoyan

    2011-12-01

    The blockage of a vena cava filter (VCF) by the captured blood clots presents a serious problem to the patients. Commercially available cone-shaped VCFs such as the Gunther Tulip filter has an inherent structural flaw that leads the captured blood clots to be trapped in their front spire areas where the flow-induced shear stress is relatively low so that the clots cannot dissolve fast enough and will accumulate, gradually block the central passages of the filters. It is well known that for a Hagen-Poiseuille flow in a circular tube, the flow-induced shear stress is highest at the wall of the tube and lowest along its axis. Herein, we hypothesize that by reversely deploying a cone-shaped filter in the vena cava, the filter's blockage problem might be prevented. First of all, this kind of deployment scenario can force the captured blood clots to stay in the peripheral areas of the vena cava and keep the central passage of the filter unblocked. Secondly, this scenario can expose the captured blood clots to relatively high shear stress that may dissolve the clots faster. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Application of AI Technology for some design problems in nuclear engineering

    International Nuclear Information System (INIS)

    Yoshikawa, Hidekazu; Gofuku, Akio; Takahashi, Makoto

    1993-01-01

    We have been engaged in the research and development on advanced computer application such as artificial intelligence in the field of instrumentation, control and systems analysis of nuclear engineering, for a long period since early 80a. Since then, our research activities have covered the following areas: reactor diagnostic methods and systems, post-trip plant analyzer. module-based simulation system for NPP dynamic simulation, various intelligent support methods for light water reactor two-phase flow analysis, intelligent CAD/CAE system for conceptual design of advanced reactor, human cognitive experiment on man-machine interface and the related bio cybernetic measurement, and man-machine system design evaluation methodology development. In this paper, we will start by brief historical reviews on our past progress in the aforementioned research items to. Then, we will proceed to introduce on-going two topics and, concerning methodological development of object-oriented intelligent CAD/CAE model for conceptual design of advanced reactor, and realtime human cognitive state estimator by means of bio cybernetic measurement

  11. Design of SCADA water resource management control center by a bi-objective redundancy allocation problem and particle swarm optimization

    International Nuclear Information System (INIS)

    Dolatshahi-Zand, Ali; Khalili-Damghani, Kaveh

    2015-01-01

    SCADA is an essential system to control critical facilities in big cities. SCADA is utilized in several sectors such as water resource management, power plants, electricity distribution centers, traffic control centers, and gas deputy. The failure of SCADA results in crisis. Hence, the design of SCADA system in order to serve a high reliability considering limited budget and other constraints is essential. In this paper, a bi-objective redundancy allocation problem (RAP) is proposed to design Tehran's SCADA water resource management control center. Reliability maximization and cost minimization are concurrently considered. Since the proposed RAP is a non-linear multi-objective mathematical programming so the exact methods cannot efficiently handle it. A multi-objective particle swarm optimization (MOPSO) algorithm is designed to solve it. Several features such as dynamic parameter tuning, efficient constraint handling and Pareto gridding are inserted in proposed MOPSO. The results of proposed MOPSO are compared with an efficient ε-constraint method. Several non-dominated designs of SCADA system are generated using both methods. Comparison metrics based on accuracy and diversity of Pareto front are calculated for both methods. The proposed MOPSO algorithm reports better performance. Finally, in order to choose the practical design, the TOPSIS algorithm is used to prune the Pareto front. - Highlights: • Multi-objective redundancy allocation problem (MORAP) is proposed to design SCADA system. • Multi-objective particle swarm optimization (MOPSO) is proposed to solve MORAP. • Efficient epsilon-constraint method is adapted to solve MORAP. • Non-dominated solutions are generated on Pareto front of MORAP by both methods. • Several multi-objective metrics are calculated to compare the performance of methods

  12. Designing for student engagement in middle school science: Collaborative problem-solving in environmental science, using nanotechnology and electron microscopy

    Science.gov (United States)

    Harmer, Andrea J.

    Engaging middle-school students in scientific inquiry is typically recognized as important, but difficult. Designed to foster learner engagement, this method used an online, problem-based, science inquiry that investigated the Lehigh Gap, Palmerton Superfund Site during five weeks of collaborative classroom sessions. The inquiry prototype was authored in WISE, the Web-Based Science Inquiry Environment headquartered at UC, Berkeley. Online materials, readings, and class sessions were augmented with remote access to an electron microscope to analyze Lehigh Gap samples and an introduction to nanoscale science and nanotechnology through the ImagiNations Web site at Lehigh University. Students contributed the artifacts they generated during their research to a university database and presented them to researchers at the university working on the same problem. This approach proved highly engaging and generated design and development guidelines useful to others interested in designing for student engagement and introducing nanoscale science and electron microscopy in middle school science. This study further found that students' engaged in science inquiry both behaviorally and emotionally and on several different levels. The various levels appeared to create two hierarchies of engagement, one based on behavioral criteria and the other based on emotional criteria. For students involved in the collaborative, problem-solving science, which included experts and access to their microscopes, the highest levels of engagement seemed to empower students and create in them a passion towards science. These hierarchies are illustrated with students' direct quotes, which prove that students engaged in this particular design of science inquiry. Students' engagement in the inquiry led to their achievements in understanding nanoscale science, nanotechnology, and electron microscopy and initiated positive attitude changes towards learning science.

  13. Applications of Evolutionary Algorithms to Electromagnetic Materials Characterization and Design Problems

    Science.gov (United States)

    Frasch, Jonathan Lemoine

    Determining the electrical permittivity and magnetic permeability of materials is an important task in electromagnetics research. The method using reflection and transmission scattering parameters to determine these constants has been widely employed for many years, ever since the work of Nicolson, Ross, and Weir in the 1970's. For general materials that are homogeneous, linear, and isotropic, the method they developed (the NRW method) works very well and provides an analytical solution. For materials which possess a metal backing or are applied as a coating to a metal surface, it can be difficult or even impossible to obtain a transmission measurement, especially when the coating is thin. In such a circumstance, it is common to resort to a method which uses two reflection type measurements. There are several such methods for free-space measurements, using multiple angles or polarizations for example. For waveguide measurements, obtaining two independent sources of information from which to extract two complex parameters can be a challenge. This dissertation covers three different topics. Two of these involve different techniques to characterize conductor-backed materials, and the third proposes a method for designing synthetic validation standards for use with standard NRW measurements. All three of these topics utilize modal expansions of electric and magnetic fields to analyze propagation in stepped rectangular waveguides. Two of the projects utilize evolutionary algorithms (EA) to design waveguide structures. These algorithms were developed specifically for these projects and utilize fairly recent innovations within the optimization community. The first characterization technique uses two different versions of a single vertical step in the waveguide. Samples to be tested lie inside the steps with the conductor reflection plane behind them. If the two reflection measurements are truly independent it should be possible to recover the values of two complex

  14. Computer Problem-Solving Coaches

    Science.gov (United States)

    Hsu, Leon; Heller, Kenneth

    2005-09-01

    Computers might be able to play an important role in physics instruction by coaching students to develop good problem-solving skills. Building on previous research on student problem solving and on designing computer programs to teach cognitive skills, we are developing a prototype computer coach to provide students with guided practice in solving problems. In addition to helping students become better problem solvers, such programs can be useful in studying how students learn to solve problems and how and if problem-solving skills can be transferred from a computer to a pencil-and-paper environment.

  15. Design problems of a continuous injector of many amperes of MeV deuterium neutrals

    International Nuclear Information System (INIS)

    Fink, J.H.

    1976-10-01

    A continuous injector of many amperes of MeV deuterium neutrals will require high currents of negative deuterium ions to be generated, accelerated and stripped of electrons by methods that are not fully developed. Each of these processes as briefly described in this report, introduce constraints upon the ion optics, beam line pumping, and high voltage stand-off that must be mutually resolved. Although the design of such an injector represents a difficult task, there is no fundamental reason that very high current beams cannot be handled

  16. Java programming fundamentals problem solving through object oriented analysis and design

    CERN Document Server

    Nair, Premchand S

    2008-01-01

    While Java texts are plentiful, it's difficult to find one that takes a real-world approach, and encourages novice programmers to build on their Java skills through practical exercise. Written by an expert with 19 experience teaching computer programming, Java Programming Fundamentals presents object-oriented programming by employing examples taken from everyday life. Provides a foundation in object-oriented design principles and UML notation Describes common pitfalls and good programming practicesFurnishes supplemental links, documents, and programs on its companion website, www.premnair.netU

  17. THE LACK OF SCIENTIFIC ATTITUDE AS A PROBLEM IN THE DESIGNING OF A YACHT CLUB

    Directory of Open Access Journals (Sweden)

    Екатерина Анатольевна Пирогова

    2016-08-01

    Full Text Available The papers draws attention the fact that nowadays there is a lack of scientific basis for designinh of yacht clubs and ports. There is no legal framework and many terms are misinterpreted. This can be observed in the new decree issued by the Government of the Leningrad region. The author considers it is necessary to develop a uniform legal framework for the design of yacht clubs and ports. The framework should posess a single classification, which allows not only to project a modern yacht education, but to develop yachting infrastructure.

  18. NJOY-97, General ENDF/B Processing System for Reactor Design Problems

    International Nuclear Information System (INIS)

    1999-01-01

    larger test-problem suite, a new revision control system, and some changes to the user input. 3 - Restrictions on the complexity of the problem: None noted

  19. A comprehensive quadratic assignment problem for an integrated layout design of final assembly line and manufacturing feeder cells

    Directory of Open Access Journals (Sweden)

    Masoud Rabbani

    2017-04-01

    Full Text Available Assembly lines and cellular manufacturing systems (CMSs design have been widely used in the literature. However the integration of these manufacturing concepts is neglected in an environment where parts need to be assembled after production in different shops. In this paper, a comprehensive quadratic assignment problem is developed for the assignment of machines of each part manufacturing cell, sub-assembly tasks of each sub-assembly cell as well as the assignment of different cells and final assembly tasks within the shop floor in their relevant predetermined locations. A genetic algorithm (GA as well as a memetic algorithm (MA consisting of the proposed GA and Tabu search (TS algorithm are proposed and implemented on different size numerical examples. The obtained results show the efficiency of both algorithms to reach near optimal solutions compared to the optimal solution of small-sized problems.

  20. Computational benefits using artificial intelligent methodologies for the solution of an environmental design problem: saltwater intrusion.

    Science.gov (United States)

    Papadopoulou, Maria P; Nikolos, Ioannis K; Karatzas, George P

    2010-01-01

    Artificial Neural Networks (ANNs) comprise a powerful tool to approximate the complicated behavior and response of physical systems allowing considerable reduction in computation time during time-consuming optimization runs. In this work, a Radial Basis Function Artificial Neural Network (RBFN) is combined with a Differential Evolution (DE) algorithm to solve a water resources management problem, using an optimization procedure. The objective of the optimization scheme is to cover the daily water demand on the coastal aquifer east of the city of Heraklion, Crete, without reducing the subsurface water quality due to seawater intrusion. The RBFN is utilized as an on-line surrogate model to approximate the behavior of the aquifer and to replace some of the costly evaluations of an accurate numerical simulation model which solves the subsurface water flow differential equations. The RBFN is used as a local approximation model in such a way as to maintain the robustness of the DE algorithm. The results of this procedure are compared to the corresponding results obtained by using the Simplex method and by using the DE procedure without the surrogate model. As it is demonstrated, the use of the surrogate model accelerates the convergence of the DE optimization procedure and additionally provides a better solution at the same number of exact evaluations, compared to the original DE algorithm.

  1. Problems and solutions in high-rate multichannel hybrid photodiode design The CMS experience

    CERN Document Server

    Cushman, P B

    2002-01-01

    The unique conditions of the CMS experiment (4 T magnetic field, restricted access, high neutron radiation, and 25-ns bunch-crossings) necessitated the development of a new type of high-rate multichannel hybrid photodiode for the tile/fiber hadronic calorimeter. New complexities arose in the push toward high-rate operation, necessitating design changes in the diode structure and surface treatment. The product is now capable of high-rate operation with low crosstalk and leakage current. Lifetime studies of high-voltage behavior, total charge, and irradiation have shown that the tubes will survive the ten years of CMS running with only a few percent change in gain and manageable leakage current rise. (13 refs).

  2. Gas-dynamic problems in off-design operation of supersonic inlets ( review)

    Science.gov (United States)

    Zvegintsev, V. I.

    2017-11-01

    Modern concepts of operation of supersonic inlets of high-velocity air-breathing engines are analyzed. It is demonstrated that the flow in the engine duct becomes extremely complicated in off-design modes of inlet operation, which can lead to unpredictable consequences, in particular, to inlet unstart. The term "inlet unstart" is considered in the present paper as a synonym of the absence of theoretical understanding and prediction of gas-dynamic phenomena. Various approaches are proposed to ensure self-regulation of the inlet-combustor system for air-breathing engines. Possible directions of further research are indicated for the purpose of stable operation of inlets in a wide range of flight conditions.

  3. Sensitivity analysis of molecular design problem for the development of novel working fluids for power cycles

    DEFF Research Database (Denmark)

    Frutiger, Jerome; Abildskov, Jens; Sin, Gürkan

    and energy balances for a pump, a condenser, a turbine and an evaporator. As regards sensitivity analysis method, a global sensitivity analysis is performed based on Morris screening to determine which change of input parameters have important effects on the net power output. The screening is composed......In recent years there is a large availability of low-temperature heat sources in different applications such as waste heat in chemical industries and refrigeration plants as well as renewable energy sources such as biomass combustion, geothermal and solar heat sources. Power cycles are an important...... technology to convert such waste heat sources into usable energy. So far the low-temperature heat is not utilized efficiently for electricity generation. To optimize the heat transfer process and the power generation, the influence of the working fluid, the cycle designs and the operating conditions is vital...

  4. Designing Undergraduate-Level Organic Chemistry Instructional Problems: Seven Ideas from a Problem-Solving Study of Practicing Synthetic Organic Chemists

    Science.gov (United States)

    Raker, Jeffrey R.; Towns, Marcy H.

    2012-01-01

    The development of curricular problems based on the practice of synthetic organic chemistry has not been explored in the literature. Such problems have broadly been hypothesized to promote student persistence and interest in STEM fields. This study reports seven ideas about how practice-based problems can be developed for sophomore-level organic…

  5. A Novel Intensive Distribution Logistics Network Design and Profit Allocation Problem considering Sharing Economy

    Directory of Open Access Journals (Sweden)

    Mi Gan

    2018-01-01

    Full Text Available The rapid growth of logistics distribution highlights the problems including the imperfect infrastructure of logistics distribution network, the serious shortage of distribution capacity of each individual enterprise, and the high cost of distribution in China. While the development of sharing economy makes it possible to achieve the integration of whole social logistic resources, big data technology can grasp customer’s logistics demand accurately on the basis of analyzing the customer’s logistics distribution preference, which contributes to the integration and optimization of the whole logistics resources. This paper proposes a kind of intensive distribution logistics network considering sharing economy, which assumes that all the social logistics suppliers build a strategic alliance, and individual idle logistics resources are also used to deal with distribution needs. Analyzing customer shopping behavior by the big data technology to determine customer’s logistics preference on the basis of dividing the customer’s logistics preference into high speed, low cost, and low pollution and then constructing the corresponding objective function model according to different logistics preferences, we obtain the intensive distribution logistics network model and solve it with heuristic algorithm. Furthermore, this paper analyzes the mechanism of interest distribution of the participants in the distribution network and puts forward an improved interval Shapley value method considering both satisfaction and contribution, with case verifying the feasibility and effectiveness of the model. The results showed that, compared with the traditional Shapley method, distribution coefficient calculated by the improved model could be fairer, improve stakeholder satisfaction, and promote the sustainable development of the alliance as well.

  6. RESEARCH OF PROBLEMS OF DESIGN OF COMPLEX TECHNICAL PROVIDING AND THE GENERALIZED MODEL OF THEIR DECISION

    Directory of Open Access Journals (Sweden)

    A. V. Skrypnikov

    2015-01-01

    Full Text Available Summary. In this work the general ideas of a method of V. I. Skurikhin taking into account the specified features develop and questions of the analysis and synthesis of a complex of technical means, with finishing them to the level suitable for use in engineering practice of design of information management systems are in more detail considered. In work the general system approach to the solution of questions of a choice of technical means of the information management system is created, the general technique of the sys tem analysis and synthesis of a complex of the technical means and its subsystems providing achievement of extreme value of criterion of efficiency of functioning of a technical complex of the information management system is developed. The main attention is paid to the applied party of system researches of complex technical providing, in particular, to definition of criteria of quality of functioning of a technical complex, development of methods of the analysis of information base of the information management system and definition of requirements to technical means, and also methods of structural synthesis of the main subsystems of complex technical providing. Thus, the purpose is research on the basis of system approach of complex technical providing the information management system and development of a number of methods of the analysis and the synthesis of complex technical providing suitable for use in engineering practice of design of systems. The well-known paradox of development of management information consists of that parameters of the system, and consequently, and requirements to the complex hardware, can not be strictly reasonable to development of algorithms and programs, and vice versa. The possible method of overcoming of these difficulties is prognostication of structure and parameters of complex hardware for certain management informations on the early stages of development, with subsequent clarification and

  7. The Problem of Form in Objects under Redevelopment (On the Basis of Bytom Market Square Redevelopment Design) / Problem Formy W Obiektach Przebudowywanych (Na Przykładzie Projektu Realizacyjnego Przebudowy Bytomskiego Rynku)

    Science.gov (United States)

    Maryńczuk, Paweł

    2015-03-01

    The author believes that if a designer has performed many design or research works entailing solutions to various problems, it is recommendable to consider and become aware of previously used methods whose application might have been unwitting or instinctive. The outcome of such reflection can be worth describing and recording in order to formulate a set of guidelines useful in the future. Such methods, being intuitive in nature, are often tied to the designer's subconsciousness, thus are rarely expressed in a clear manner. By using own methods a designer can prove that space should be composed in a given way in order to address specific needs and defined objectives. All this is aimed at preventing accidental formation of space. An example of reasoning serving the aforementioned purpose can be found in a method referred to as CQC or Composition Quality Control, the application of which facilitates intentional shaping of an architectural piece of work. Autor uważa uważa, że jeśli projektant ma za sobą wiele prac projektowych lub też prac badawczych, które połączone były z rozwiązywaniem różnych problemów, to warto zastanowić się i uświadomić sobie sposoby, które dotychczas - może nieświadomie lub odruchowo - były stosowane. Wynik refleksji warto opisać i zapisać po to, żeby ująć go w układ wskazań na przyszłość. Metody te, mając charakter intuicyjny, często związane są z podświadomością projektanta, w związku z tym rzadko można spotkać je jako wyrażone w sposób wyraźny. Stosując metody własne można dowieść, że przestrzeń winna być komponowana tak, a nie inaczej dla określonych potrzeb i wytyczonych celów tak, aby jej forma nie była przypadkowa. Przykładem takiego rozumowania jest przyjeta metoda KJK, której zastosowanie pomaga w swiadomym kształtowaniu dzieła architektonicznego.

  8. Design and analysis of biorefineries based on raw glycerol: addressing the glycerol problem.

    Science.gov (United States)

    Posada, John A; Rincón, Luis E; Cardona, Carlos A

    2012-05-01

    Glycerol as a low-cost by-product of the biodiesel industry can be considered a renewable building block for biorefineries. In this work, the conversion of raw glycerol to nine added-value products obtained by chemical (syn-gas, acrolein, and 1,2-propanediol) or bio-chemical (ethanol, 1,3-propanediol, d-lactic acid, succinic acid, propionic acid, and poly-3-hydroxybutyrate) routes were considered. The technological schemes for these synthesis routes were designed, simulated, and economically assessed using Aspen Plus and Aspen Icarus Process Evaluator, respectively. The techno-economic potential of a glycerol-based biorefinery system for the production of fuels, chemicals, and plastics was analyzed using the commercial Commercial Sale Price/Production Cost ratio criteria, under different production scenarios. More income can be earned from 1,3-propanediol and 1,2-propanediol production, while less income would be obtained from hydrogen and succinic acid. This analysis may be useful mainly for biodiesel producers since several profitable alternatives are presented and discussed. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. A multiobjective optimization model and an orthogonal design-based hybrid heuristic algorithm for regional urban mining management problems.

    Science.gov (United States)

    Wu, Hao; Wan, Zhong

    2018-02-01

    In this paper, a multiobjective mixed-integer piecewise nonlinear programming model (MOMIPNLP) is built to formulate the management problem of urban mining system, where the decision variables are associated with buy-back pricing, choices of sites, transportation planning, and adjustment of production capacity. Different from the existing approaches, the social negative effect, generated from structural optimization of the recycling system, is minimized in our model, as well as the total recycling profit and utility from environmental improvement are jointly maximized. For solving the problem, the MOMIPNLP model is first transformed into an ordinary mixed-integer nonlinear programming model by variable substitution such that the piecewise feature of the model is removed. Then, based on technique of orthogonal design, a hybrid heuristic algorithm is developed to find an approximate Pareto-optimal solution, where genetic algorithm is used to optimize the structure of search neighborhood, and both local branching algorithm and relaxation-induced neighborhood search algorithm are employed to cut the searching branches and reduce the number of variables in each branch. Numerical experiments indicate that this algorithm spends less CPU (central processing unit) time in solving large-scale regional urban mining management problems, especially in comparison with the similar ones available in literature. By case study and sensitivity analysis, a number of practical managerial implications are revealed from the model. Since the metal stocks in society are reliable overground mineral sources, urban mining has been paid great attention as emerging strategic resources in an era of resource shortage. By mathematical modeling and development of efficient algorithms, this paper provides decision makers with useful suggestions on the optimal design of recycling system in urban mining. For example, this paper can answer how to encourage enterprises to join the recycling activities

  10. Uterine rupture without previous caesarean delivery

    DEFF Research Database (Denmark)

    Thisted, Dorthe L. A.; H. Mortensen, Laust; Krebs, Lone

    2015-01-01

    OBJECTIVE: To determine incidence and patient characteristics of women with uterine rupture during singleton births at term without a previous caesarean delivery. STUDY DESIGN: Population based cohort study. Women with term singleton birth, no record of previous caesarean delivery and planned...... vaginal delivery (n=611,803) were identified in the Danish Medical Birth Registry (1997-2008). Medical records from women recorded with uterine rupture during labour were reviewed to ascertain events of complete uterine rupture. Relative Risk (RR) and adjusted Relative Risk Ratio (aRR) of complete uterine...... rupture with 95% confidence intervals (95% CI) were ascertained according to characteristics of the women and of the delivery. RESULTS: We identified 20 cases with complete uterine rupture. The incidence of complete uterine rupture among women without previous caesarean delivery was about 3...

  11. Effectiveness and cost of car front end design for pedestrian injury prevention and the problem of conflicting requirements : a literature review.

    NARCIS (Netherlands)

    Kampen, L.T.B. van

    1991-01-01

    SWOV carried out a literature review on the subject of car front end design for pedestrian injury prevention. The review is aimed at effectiveness and cost of such a design and at the problem of conflicting requirements. Such requirements are existing safety standards and common design rules on the

  12. Docking and Molecular Dynamics Calculations of Some Previously Studied and newly Designed Ligands to Catalytic Core Domain of HIV-1 Integrase and an Investigation to Effects of Conformational Changes of Protein on Docking Results

    Directory of Open Access Journals (Sweden)

    Selami Ercan

    2016-10-01

    Full Text Available Nowadays, AIDS still remains as a worldwide pandemic and continues to cause many death which arise from HIV-1 virus. For nearly 35 years, drugs that target various steps of virus life cycle have been developed. HIV-1 integrase is the one of these steps which is essential for virus life cycle. Computer aided drug design is being used in many drug design studies as also used in development of the first HIV-1 integrase inhibitor Raltegravir. In this study 3 ligands which are used as HIV-1 integrase inhibitors and 4 newly designed ligands were docked to catalytic core domain of HIV-1 integrase. Each of ligands docked to three different conformations of protein. Prepared complexes (21 item were carried out by 50 ns MD simulations and results were analyzed. Finally, the binding free energies of ligands were calculated. Hereunder, it was determined that designed ligands L01 and L03 gave favorable results. The questions about the ligands which have low docking scores in a conformation of protein could give better scores in another conformation of protein and if the MD simulations carry the different oriented and different localized ligands in same position at the end of simulation were answered.

  13. Design and operation problems related to water curtain system for underground water-sealed oil storage caverns

    Directory of Open Access Journals (Sweden)

    Zhongkui Li

    2016-10-01

    Full Text Available The underground water-sealed storage technique is critically important and generally accepted for the national energy strategy in China. Although several small underground water-sealed oil storage caverns have been built in China since the 1970s, there is still a lack of experience for large-volume underground storage in complicated geological conditions. The current design concept of water curtain system and the technical instruction for system operation have limitations in maintaining the stability of surrounding rock mass during the construction of the main storage caverns, as well as the long-term stability. Although several large-scale underground oil storage projects are under construction at present in China, the design concepts and construction methods, especially for the water curtain system, are mainly based on the ideal porosity medium flow theory and the experiences gained from the similar projects overseas. The storage projects currently constructed in China have the specific features such as huge scale, large depth, multiple-level arrangement, high seepage pressure, complicated geological conditions, and high in situ stresses, which are the challenging issues for the stability of the storage caverns. Based on years' experiences obtained from the first large-scale (millions of cubic meters underground water-sealed oil storage project in China, some design and operation problems related to water curtain system during project construction are discussed. The drawbacks and merits of the water curtain system are also presented. As an example, the conventional concept of “filling joints with water” is widely used in many cases, as a basic concept for the design of the water curtain system, but it is immature. In this paper, the advantages and disadvantages of the conventional concept are pointed out, with respect to the long-term stability as well as the safety of construction of storage caverns. Finally, new concepts and principles

  14. Designing problem-based curricula: The role of concept mapping in scaffolding learning for the health sciences

    Directory of Open Access Journals (Sweden)

    Susan M. Bridges

    2015-03-01

    Full Text Available While the utility of concept mapping has been widely reported in primary and secondary educational contexts, its application in the health sciences in higher education has been less frequently noted. Two case studies of the application of concept mapping in undergraduate and postgraduate health sciences are detailed in this paper. The case in undergraduate dental education examines the role of concept mapping in supporting problem-based learning and explores how explicit induction into the principles and practices of CM has add-on benefits to learning in an inquiry-based curriculum. The case in postgraduate medical education describes the utility of concept mapping in an online inquiry-based module design. Specific attention is given to applications of CMapTools™ software to support the implementation of Novakian concept mapping in both inquiry-based curricular contexts.

  15. Preliminary design study and problem definition for intense CW superconducting deuteron ion linac for fusion material study

    International Nuclear Information System (INIS)

    Tanabe, Y.; Kakutani, N.; Ota, T.; Yamaguchi, A.; Takeda, O.; Wachi, Y.; Yamazaki, C.; Morii, Y.

    1997-01-01

    The advantages of superconducting (SC) cavity have been verified for many electron accelerators and the application of SC cavity to high intensity CW ion linacs is currently being considered. These linacs have been required for neutron irradiation tests of materials, transmutation of nuclear waste and so on. An SC linac consisting of SC cavities, SC quadrupole magnets and cryostats, was preliminarily designed to investigate the feasibility of applying to deuteron machine. Beam dynamics analysis was also carried out by using a modified PARMILA code in order to confirm no beam loss. Since radiation damage of superconductors is especially severe for such a machine, data relating to the damage were surveyed and discussed. Moreover, other major facilities such as cryogenic system, radio frequency amplifier and RF control system were considered. Many problems to be solved were defined but no critical issues were found. In consequence, it became clear that SC linac is very attractive and competitive with a room-temperature linac. (orig.)

  16. Learning Design of Problem Based Learning Model Based on Recommendations of Sintax Study and Contents Issues on Physics Impulse Materials with Experimental Activities

    Directory of Open Access Journals (Sweden)

    Kristia Agustina

    2017-08-01

    Full Text Available This study aims to design learning Problem Based Learning Model based on syntax study recommendations and content issues on Physics Impulse materials through experiments. This research is a development research with Kemp model. The reference for making the learning design is the result of the syntax study and the content of existing PBL implementation problems from Agustina research. This instructional design is applied to the physics material about Impulse done through experimental activity. Limited trials were conducted on the SWCU Physics Education Study Program students group Salatiga, while the validity test was conducted by high school teachers and physics education lecturers. The results of the trial evaluation are limited and the validity test is used to improve the designs that have been made. The conclusion of this research is the design of learning by using PBL model on Impuls material by referring the result of syntax study and the problem content of existing PBL implementation can be produced by learning activity designed in laboratory experiment activity. The actual problem for Impuls material can be used car crash test video at factory. The results of validation tests and limited trials conducted by researchers assessed that the design of learning made by researchers can be used with small revisions. Suggestions from this research are in making learning design by using PBL model to get actual problem can by collecting news that come from newspaper, YouTube, internet, and television.

  17. Challenges in designing appropriate scaffolding to improve students' representational consistency: The case of a Gauss's law problem

    Science.gov (United States)

    Maries, Alexandru; Lin, Shih-Yin; Singh, Chandralekha

    2017-12-01

    Prior research suggests that introductory physics students have difficulty with graphing and interpreting graphs. Here, we discuss an investigation of student difficulties in translating between mathematical and graphical representations for a problem in electrostatics and the effect of increasing levels of scaffolding on students' representational consistency. Students in calculus-based introductory physics were given a typical problem that can be solved using Gauss's law involving a spherically symmetric charge distribution in which they were asked to write a mathematical expression for the electric field in various regions and then plot the electric field. In study 1, we found that students had great difficulty in plotting the electric field as a function of the distance from the center of the sphere consistent with the mathematical expressions in various regions, and interviews with students suggested possible reasons which may account for this difficulty. Therefore, in study 2, we designed two scaffolding interventions with levels of support which built on each other (i.e., the second scaffolding level built on the first) in order to help students plot their expressions consistently and compared the performance of students provided with scaffolding with a comparison group which was not given any scaffolding support. Analysis of student performance with different levels of scaffolding reveals that scaffolding from an expert perspective beyond a certain level may sometimes hinder student performance and students may not even discern the relevance of the additional support. We provide possible interpretations for these findings based on in-depth, think-aloud student interviews.

  18. Design paper: A phase II study of Bevacizumab and Erlotinib in patients with non-Squamous non-small cell lung cancer that is refractory or relapsed after 1-2 previous Treatment (BEST

    Directory of Open Access Journals (Sweden)

    Kim Young H

    2011-05-01

    Full Text Available Abstract Background Combination of erlotinib and bevacizumab is a promising regimen in advanced non-squamous non-small-cell lung cancer (NSCLC. We are conducting a single arm phase II trial which aims to evaluate the efficacy and safety of this regime as a second- or third-line chemotherapy. Methods Key eligibility criteria were histologically or cytologically confirmed non-squamous NSCLC, stage III/IV or recurrent NSCLC not indicated radical chemoradiation, prior one or two regimen of chemotherapy, age 20 years or more, and performance status of two or less. The primary endpoint is objective response rate. The secondary endpoints include overall survival, progression-free survival, disease control rate and incidence of adverse events. This trial plans to accrue 80 patients based on a two-stage design employing a binomial distribution with an alternative hypothesis response rate of 35% and a null hypothesis threshold response rate of 20%. A subset analysis according to EGFR mutation status is planned. Discussion We have presented the design of a single arm phase II trial to evaluate the efficacy and safety of combination of bevacizumab and erlotinib in advanced non-squamous NSCLC patients. In particular we are interested in determining the merit of further development of this regimen and whether prospective patient selection using EGFR gene is necessary in future trials. Trial registration This trial was registered at the UMIN Clinical Trials Registry as UMIN000004255 (http://www.umin.ac.jp/ctr/index.htm.

  19. The Effects of Using Drawings in Developing Young Children's Mathematical Word Problem Solving: A Design Experiment with Third-Grade Hungarian Students

    Science.gov (United States)

    Csikos, Csaba; Szitanyi, Judit; Kelemen, Rita

    2012-01-01

    The present study aims to investigate the effects of a design experiment developed for third-grade students in the field of mathematics word problems. The main focus of the program was developing students' knowledge about word problem solving strategies with an emphasis on the role of visual representations in mathematical modeling. The experiment…

  20. Problem-based learning: a strategic learning system design for the education of healthcare professionals in the 21st century.

    Science.gov (United States)

    Gwee, Matthew Choon-Eng

    2009-05-01

    Problem-based learning (PBL) was first implemented by McMaster University medical school in 1969 as a radical, innovative, and alternative pathway to learning in medical education, thus setting a new educational trend. PBL has now spread widely across the globe and beyond the healthcare disciplines, and has prevailed for almost four decades. PBL is essentially a strategic learning system design, which combines several complementary educational principles for the delivery of instruction. PBL is specifically aimed at enhancing and optimizing the educational outcomes of learner-centered, collaborative, contextual, integrated, self-directed, and reflective learning. The design and delivery of instruction in PBL involve peer teaching and learning in small groups through the social construction of knowledge using a real-life problem case to trigger the learning process. Therefore, PBL represents a major shift in the educational paradigm from the traditional teacher-directed (teacher-centered) instruction to student-centered (learner-centered) learning. PBL is firmly underpinned by several educational theories, but problems are often encountered in practice that can affect learning outcomes. Educators contemplating implementing PBL in their institutions should have a clear understanding of its basic tenets, its practice and its philosophy, as well as the issues, challenges, and opportunities associated with its implementation. Special attention should be paid to the training and selection of PBL tutors who have a critical role in the PBL process. Furthermore, a significant change in the mindsets of both students and teachers are required for the successful implementation of PBL. Thus, effective training programs for students and teachers must precede its implementation. PBL is a highly resource-intensive learning strategy and the returns on investment (i.e. the actual versus expected learning outcomes) should be carefully and critically appraised in the decision

  1. Problem-Based Learning: A Strategic Learning System Design For The Education Of Healthcare Professionals in the 21ST Century

    Directory of Open Access Journals (Sweden)

    Matthew Choon-Eng Gwee

    2009-05-01

    Full Text Available Problem-based learning (PBL was first implemented by McMaster University medical school in 1969 as a radical, innovative, and alternative pathway to learning in medical education, thus setting a new educational trend. PBL has now spread widely across the globe and beyond the healthcare disciplines, and has prevailed for almost four decades. PBL is essentially a strategic learning system design, which combines several complementary educational principles for the delivery of instruction. PBL is specifically aimed at enhancing and optimizing the educational outcomes of learner-centered, collaborative, contextual, integrated, self-directed, and reflective learning. The design and delivery of instruction in PBL involve peer teaching and learning in small groups through the social construction of knowledge using a real-life problem case to trigger the learning process. Therefore, PBL represents a major shift in the educational paradigm from the traditional teacher-directed (teacher-centered instruction to student-centered (learner-centered learning. PBL is firmly underpinned by several educational theories, but problems are often encountered in practice that can affect learning outcomes. Educators contemplating implementing PBL in their institutions should have a clear understanding of its basic tenets, its practice and its philosophy, as well as the issues, challenges, and opportunities associated with its implementation. Special attention should be paid to the training and selection of PBL tutors who have a critical role in the PBL process. Furthermore, a significant change in the mindsets of both students and teachers are required for the successful implementation of PBL. Thus, effective training programs for students and teachers must precede its implementation. PBL is a highly resource-intensive learning strategy and the returns on investment (i.e. the actual versus expected learning outcomes should be carefully and critically appraised in the

  2. The Influence of Game Design on the Collaborative Problem Solving Process: A Cross-Case Study of Multi-Player Collaborative Gameplay Analysis

    Science.gov (United States)

    Yildirim, Nilay

    2013-01-01

    This cross-case study examines the relationships between game design attributes and collaborative problem solving process in the context of multi-player video games. The following game design attributes: sensory stimuli elements, level of challenge, and presentation of game goals and rules were examined to determine their influence on game…

  3. A Comparison of Problems at the Grassroots Level in India Identified by Adults and Children: Implications for Design and Technology Education

    Science.gov (United States)

    Datt, Sachin; Chunawala, Sugra

    2018-01-01

    The focus of Design and Technology (D&T) education (Wilson & Harris, 2004) has been on designing and making activities and in developing technological capabilities amongst students. Innovation is an important aspect of D&T that helps in creating new products and artefacts to overcome the limitations of existing ones. Problem solving…

  4. Method and software to solution of inverse and inverse design fluid flow and heat transfer problems is compatible with CFD-software

    Energy Technology Data Exchange (ETDEWEB)

    Krukovsky, P.G. [Institute of Engineering Thermophysics, National Academy of Sciences of Ukraine, Kiev (Ukraine)

    1997-12-31

    The description of method and software FRIEND which provide a possibility of solution of inverse and inverse design problems on the basis of existing (base) CFD-software for solution of direct problems (in particular, heat-transfer and fluid-flow problems using software PHOENICS) are presented. FRIEND is an independent additional module that widens the operational capacities of the base software unified with this module. This unifying does not require any change or addition to the base software. Interfacing of FRIEND and the base software takes place through input and output files of the base software. A brief description of the computational technique applied for the inverse problem solution, same detailed information on the interfacing of FRIEND and CFD-software and solution results for testing inverse and inverse design problems, obtained using the tandem CFD-software PHOENICS and FRIEND, are presented. (author) 9 refs.

  5. An adaptive Gaussian process-based method for efficient Bayesian experimental design in groundwater contaminant source identification problems: ADAPTIVE GAUSSIAN PROCESS-BASED INVERSION

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jiangjiang [College of Environmental and Resource Sciences, Zhejiang University, Hangzhou China; Li, Weixuan [Pacific Northwest National Laboratory, Richland Washington USA; Zeng, Lingzao [College of Environmental and Resource Sciences, Zhejiang University, Hangzhou China; Wu, Laosheng [Department of Environmental Sciences, University of California, Riverside California USA

    2016-08-01

    Surrogate models are commonly used in Bayesian approaches such as Markov Chain Monte Carlo (MCMC) to avoid repetitive CPU-demanding model evaluations. However, the approximation error of a surrogate may lead to biased estimations of the posterior distribution. This bias can be corrected by constructing a very accurate surrogate or implementing MCMC in a two-stage manner. Since the two-stage MCMC requires extra original model evaluations, the computational cost is still high. If the information of measurement is incorporated, a locally accurate approximation of the original model can be adaptively constructed with low computational cost. Based on this idea, we propose a Gaussian process (GP) surrogate-based Bayesian experimental design and parameter estimation approach for groundwater contaminant source identification problems. A major advantage of the GP surrogate is that it provides a convenient estimation of the approximation error, which can be incorporated in the Bayesian formula to avoid over-confident estimation of the posterior distribution. The proposed approach is tested with a numerical case study. Without sacrificing the estimation accuracy, the new approach achieves about 200 times of speed-up compared to our previous work using two-stage MCMC.

  6. Monitoring of the operation of a nuclear power station with design problems in an importing country: The Almaraz power station

    International Nuclear Information System (INIS)

    Reig, J.

    1984-01-01

    The purpose of this paper is to describe the regulatory activities carried out in Spain as a result of the design problem occurring in the steam generators during operation of Unit I of the Almaraz nuclear power station. First, a brief introduction is given to the operating history and characteristics of Unit I of Almaraz. Particular attention is paid to the specific licences issued subsequent to commercial operation which place limitations on the operation of the station and to the operational incidents of which the Nuclear Safety Council (CSN) has been notified. Next, a description is provided of the safety evaluation carried out by the CSN. Three aspects merit particular attention: methodology, evaluation and conclusions. The methodology applied by an importing country is normally based on that of the country of origin of the design, so that the overall evaluation by the NRC has been considered sufficiently representative of aspects specific to the Almaraz power station. In this regard the importance of international collaboration is clearly seen as a principal instrument for performing the evaluation. In the evaluation a distinction is made between general and specific aspects and between inspection programmes and quality assurance requirements. In addition, the conclusions leading to the requirement of the imposition of additional limitations on the operating licence are stated. Apart from the safety evaluation carried out by the CSN, other regulatory activities have been performed over this two-year period. These activities, which include site inspections, audits of the principal supplier company, other independent calculations and so on, are described. Lastly, the paper refers to the lessons learned from the operation of the above-mentioned unit, which are immediately applicable to other Spanish nuclear power stations. (author)

  7. General design and main problems of a gas-heavy-water power reactor contained in a pressure vessel

    International Nuclear Information System (INIS)

    Roche, R.; Gaudez, J.C.

    1964-01-01

    In the framework of research carried out on a CO 2 -cooled power reactor moderated by heavy water, the so-called 'pressure vessel' solution involves the total integration of the core, of the primary circuit (exchanges and blowers) and of the fuel handling machine inside a single, strong, sealed vessel made of pre-stressed concrete. A vertical design has been chosen: the handling 'attic' is placed above the core, the exchanges being underneath. This solution makes it possible to standardize the type of reactor which is moderated by heavy-water or graphite and cooled by a downward stream of carbon dioxide gas; it has certain advantages and disadvantages with respect to the pressure tube solution and these are considered in detail in this report. Extrapolation presents in particular.problems due specifically to the heavy water (for example its cooling,its purification, the balancing of the pressures of the heavy water and of the gas, the assembling of the internal structures, the height of the attic, etc. (authors) [fr

  8. Enhancing Problem-Based Learning Designs with a Single E-Learning Scaffolding Tool: Two Case Studies Using Challenge FRAP

    Science.gov (United States)

    Stewart, Terry M.; MacIntyre, William R.; Galea, Victor J.; Steel, Caroline H.

    2007-01-01

    Problem-based learning (PBL) is a powerful instructional approach. By working through assessable complex problem-solving tasks learners can be encouraged to actively engage in investigation and inquiry and to use high level cognitive thought processes to solve real-life problems in professional contexts. A critical element of a successful PBL…

  9. Design of problem-specific evolutionary algorithm/mixed-integer programming hybrids: two-stage stochastic integer programming applied to chemical batch scheduling

    Science.gov (United States)

    Urselmann, Maren; Emmerich, Michael T. M.; Till, Jochen; Sand, Guido; Engell, Sebastian

    2007-07-01

    Engineering optimization often deals with large, mixed-integer search spaces with a rigid structure due to the presence of a large number of constraints. Metaheuristics, such as evolutionary algorithms (EAs), are frequently suggested as solution algorithms in such cases. In order to exploit the full potential of these algorithms, it is important to choose an adequate representation of the search space and to integrate expert-knowledge into the stochastic search operators, without adding unnecessary bias to the search. Moreover, hybridisation with mathematical programming techniques such as mixed-integer programming (MIP) based on a problem decomposition can be considered for improving algorithmic performance. In order to design problem-specific EAs it is desirable to have a set of design guidelines that specify properties of search operators and representations. Recently, a set of guidelines has been proposed that gives rise to so-called Metric-based EAs (MBEAs). Extended by the minimal moves mutation they allow for a generalization of EA with self-adaptive mutation strength in discrete search spaces. In this article, a problem-specific EA for process engineering task is designed, following the MBEA guidelines and minimal moves mutation. On the background of the application, the usefulness of the design framework is discussed, and further extensions and corrections proposed. As a case-study, a two-stage stochastic programming problem in chemical batch process scheduling is considered. The algorithm design problem can be viewed as the choice of a hierarchical decision structure, where on different layers of the decision process symmetries and similarities can be exploited for the design of minimal moves. After a discussion of the design approach and its instantiation for the case-study, the resulting problem-specific EA/MIP is compared to a straightforward application of a canonical EA/MIP and to a monolithic mathematical programming algorithm. In view of the

  10. Designing Proficiency Tests to Accredit Previous Knowledge in American and British Literature in a Bilingual Education Program (Diseño de exámenes de suficiencia para acreditar el conocimiento previo en literatura americana y británica en un programa de educación bilingüe)

    Science.gov (United States)

    León Chica, César Julio; D'Costa Martínez, Catalina; Franco Jácome, Gisela

    2010-01-01

    This article aims at identifying the kind of American and British literature tests that can be designed to allow students who enter a bilingual education program at a private university in Colombia to have their previous knowledge in these two subjects accredited through a proficiency test. Students' needs, opinions, beliefs, existing commercial…

  11. The Designated Convergence Rate Problems of Consensus or Flocking of Double-Integrator Agents With General Nonequal Velocity and Position Couplings: Further Results and Patterns of Convergence Rate Contours.

    Science.gov (United States)

    Li, Wei

    2017-05-01

    This paper considers the designated convergence rate (DCR) (or the designated convergence margin) problems of consensus or flocking of coupled double-integrator agents. The DCR problems are more valuable for systems design than just convergence or stability conditions. The system setting in this paper is general, i.e., the velocity coupling and position coupling (VCPC) between agents, respectively, are set to be general and nonequal (up to rescaling), together with distinct damping and stiffness gains for the VCPC, respectively. This paper has two primary contributions on consensus: 1) further necessary and sufficient conditions are established to guarantee the DCR problems of the system, which have enriched the previous results and 2) the patterns of the convergence rate contours for the DCR are characterized, in terms of the damping and stiffness gains, which are closely related to the characteristics of the spectra of the two Laplacian matrices of the VCPC. Additionally, this paper has a contribution on matrix theory, i.e., the sufficient conditions for the simultaneous upper-triangularization of two independent Laplacian matrices, particularly from an easily verifiable topological perspective on the corresponding digraphs of these Laplacian matrices.

  12. Joint application of AI techniques, PRA and disturbance analysis methodology to problems in the maintenance and design of nuclear power plants

    International Nuclear Information System (INIS)

    Okrent, D.

    1989-01-01

    This final report summarizes the accomplishments of a two year research project entitled ''Joint Application of Artificial Intelligence Techniques, Probabilistic Risk Analysis, and Disturbance Analysis Methodology to Problems in the Maintenance and Design of Nuclear Power Plants. The objective of this project is to develop and apply appropriate combinations of techniques from artificial intelligence, (AI), reliability and risk analysis and disturbance analysis to well-defined programmatic problems of nuclear power plants. Reactor operations issues were added to those of design and maintenance as the project progressed

  13. Joint application of AI techniques, PRA and disturbance analysis methodology to problems in the maintenance and design of nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Okrent, D.

    1989-03-01

    This final report summarizes the accomplishments of a two year research project entitled Joint Application of Artificial Intelligence Techniques, Probabilistic Risk Analysis, and Disturbance Analysis Methodology to Problems in the Maintenance and Design of Nuclear Power Plants. The objective of this project is to develop and apply appropriate combinations of techniques from artificial intelligence, (AI), reliability and risk analysis and disturbance analysis to well-defined programmatic problems of nuclear power plants. Reactor operations issues were added to those of design and maintenance as the project progressed.

  14. Joint application of AI techniques, PRA and disturbance analysis methodology to problems in the maintenance and design of nuclear power plants. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Okrent, D.

    1989-03-01

    This final report summarizes the accomplishments of a two year research project entitled ``Joint Application of Artificial Intelligence Techniques, Probabilistic Risk Analysis, and Disturbance Analysis Methodology to Problems in the Maintenance and Design of Nuclear Power Plants. The objective of this project is to develop and apply appropriate combinations of techniques from artificial intelligence, (AI), reliability and risk analysis and disturbance analysis to well-defined programmatic problems of nuclear power plants. Reactor operations issues were added to those of design and maintenance as the project progressed.

  15. On the Transformation Mechanism for Formulating a Multiproduct Two-Layer Supply Chain Network Design Problem as a Network Flow Model

    Directory of Open Access Journals (Sweden)

    Mi Gan

    2014-01-01

    Full Text Available The multiproduct two-layer supply chain is very common in various industries. In this paper, we introduce a possible modeling and algorithms to solve a multiproduct two-layer supply chain network design problem. The decisions involved are the DCs location and capacity design decision and the initial distribution planning decision. First we describe the problem and give a mixed integer programming (MIP model; such problem is NP-hard and it is not easy to reduce the complexity. Inspired by it, we develop a transformation mechanism of relaxing the fixed cost and adding some virtual nodes and arcs to the original network. Thus, a network flow problem (NFP corresponding to the original problem has been formulated. Given that we could solve the NFP as a minimal cost flow problem. The solution procedures and network simplex algorithm (INS are discussed. To verify the effectiveness and efficiency of the model and algorithms, the performance measure experimental has been conducted. The experiments and result showed that comparing with MIP model solved by genetic algorithm (GA and Benders, decomposition algorithm (BD the NFP model and INS are also effective and even more efficient for both small-scale and large-scale problems.

  16. Effects of Spatial Experiences & Cognitive Styles in the Solution Process of Space-Based Design Problems in the First Year of Architectural Design Education

    Science.gov (United States)

    Erkan Yazici, Yasemin

    2013-01-01

    There are many factors that influence designers in the architectural design process. Cognitive style, which varies according to the cognitive structure of persons, and spatial experience, which is created with spatial data acquired during life are two of these factors. Designers usually refer to their spatial experiences in order to find solutions…

  17. Health Problems in Pregnancy

    Science.gov (United States)

    ... problems. You may have problems because of a health condition you had before you got pregnant. You ... being pregnant with more than one baby, a health problem in a previous pregnancy, substance abuse during ...

  18. Design and Evaluation of Digital Learning Material to Support Acquisition of Quantitative Problem-Solving Skills within Food Chemistry

    Science.gov (United States)

    Diederen, Julia; Gruppen, Harry; Hartog, Rob; Voragen, Alphons G. J.

    2005-01-01

    One of the modules in the course Food Chemistry at Wageningen University (Wageningen, The Netherlands) focuses on quantitative problem-solving skills related to chemical reactions. The intended learning outcomes of this module are firstly, to be able to translate practical food chemistry related problems into mathematical equations and to solve…

  19. Design of a Dual-Mapping Learning Approach for Problem Solving and Knowledge Construction in Ill-Structured Domains

    Science.gov (United States)

    Wu, Bian; Wang, Minhong; Spector, J. Michael; Yang, Stephen J. H.

    2013-01-01

    Problem solving has been increasingly used as an important approach to learning especially in ill-structured domains. It is assumed that knowledge can be better consolidated and extended through problem-solving experience. However, many learners do not have the ability to separate general knowledge from specific cases, which inhibits successful…

  20. Comparison of Different Toll Policies in the Dynamic Second-best Optimal Toll Design Problem : Case study on a Three-link network

    NARCIS (Netherlands)

    Sta?ková, K.; Olsder, J.J.; Bliemer, M.C.J.

    2009-01-01

    In this paper, the dynamic optimal toll design problem is considered as a one leader-many followers hierarchical non-cooperative game. On a given network the road authority as the leader tolls some links in order to reach its objective, while travelers as followers minimize their perceived travel

  1. The Influence of Function, Topography, and Setting on Noncontingent Reinforcement Effect Sizes for Reduction in Problem Behavior: A Meta-Analysis of Single-Case Experimental Design Data

    Science.gov (United States)

    Ritter, William A.; Barnard-Brak, Lucy; Richman, David M.; Grubb, Laura M.

    2018-01-01

    Richman et al. ("J Appl Behav Anal" 48:131-152, 2015) completed a meta-analytic analysis of single-case experimental design data on noncontingent reinforcement (NCR) for the treatment of problem behavior exhibited by individuals with developmental disabilities. Results showed that (1) NCR produced very large effect sizes for reduction in…

  2. Research in the Real World: Improving Adult Learners Web Search and Evaluation Skills through Motivational Design and Problem-Based Learning

    Science.gov (United States)

    Roberts, Lindsay

    2017-01-01

    How can we better engage adult learners during information literacy sessions? How do we increase students' perception of the relevance and importance of information literacy skills for academic work and life in the real world? To explore these questions, the ARCS Model of Motivational Design and Problem-Based Learning were used to develop…

  3. Student use of computer tools designed to scaffold scientific problem-solving with hypermedia resources: A case study

    Science.gov (United States)

    Oliver, Kevin Matthew

    National science standards call for increasing student exposure to inquiry and real-world problem solving. Students can benefit from open-ended learning environments that stress the engagement of real problems and the development of thinking skills and processes. The Internet is an ideal resource for context-bound problems with its seemingly endless supply of resources. Problems may arise, however, since young students are cognitively ill-prepared to manage open-ended learning and may have difficulty processing hypermedia. Computer tools were used in a qualitative case study with 12 eighth graders to determine how such implements might support the process of solving open-ended problems. A preliminary study proposition suggested students would solve open-ended problems more appropriately if they used tools in a manner consistent with higher-order critical and creative thinking. Three research questions sought to identify: how students used tools, the nature of science learning in open-ended environments, and any personal or environmental barriers effecting problem solving. The findings were mixed. The participants did not typically use the tools and resources effectively. They successfully collected basic information, but infrequently organized, evaluated, generated, and justified their ideas. While the students understood how to use most tools procedurally, they lacked strategic understanding for why tool use was necessary. Students scored average to high on assessments of general content understanding, but developed artifacts suggesting their understanding of specific micro problems was naive and rife with misconceptions. Process understanding was also inconsistent, with some students describing basic problem solving processes, but most students unable to describe how tools could support open-ended inquiry. Barriers to effective problem solving were identified in the study. Personal barriers included naive epistemologies, while environmental barriers included a

  4. Problems of development and ecological construction in terms of design and construction activities in the Volgograd region

    OpenAIRE

    Taranova Anna Valer'evna; Borisova Natal'ja Ivanovna

    2016-01-01

    The analysis of existing problems and the further development of ecological construction in the Volgograd region. Discusses the problem of socio-environmental plan in terms of project construction activities. The necessity of identifying the sources of negative impact on the construction of residential properties, define solutions for their further elimination, the authors show the necessity of using environmental innovation techniques in modern construction industry.

  5. Solving the Problem of Multiple-Criteria Building Design Decisions with respect to the Fire Safety of Occupants: An Approach Based on Probabilistic Modelling

    Directory of Open Access Journals (Sweden)

    Egidijus Rytas Vaidogas

    2015-01-01

    Full Text Available The design of buildings may include a comparison of alternative architectural and structural solutions. They can be developed at different levels of design process. The alternative design solutions are compared and ranked by applying methods of multiple-criteria decision-making (MCDM. Each design is characterised by a number of criteria used in a MCDM problem. The paper discusses how to choose MCDM criteria expressing fire safety related to alternative designs. Probability of a successful evacuation of occupants from a building fire and difference between evacuation time and time to untenable conditions are suggested as the most important criteria related to fire safety. These two criteria are treated as uncertain quantities expressed by probability distributions. Monte Carlo simulation of fire and evacuation processes is natural means for an estimation of these distributions. The presence of uncertain criteria requires applying stochastic MCDM methods for ranking alternative designs. An application of the safety-related criteria is illustrated by an example which analyses three alternative architectural floor plans prepared for a reconstruction of a medical building. A MCDM method based on stochastic simulation is used to solve the example problem.

  6. Design and Evaluation of Digital Learning Material to Support Acquisition of Quantitative Problem-Solving Skills Within Food Chemistry

    NARCIS (Netherlands)

    Diederen, J.; Gruppen, H.; Hartog, R.; Voragen, A.G.J.

    2005-01-01

    One of the modules in the course Food Chemistry at Wageningen University (Wageningen, The Netherlands) focuses on quantitative problem-solving skills related to chemical reactions. The intended learning outcomes of this module are firstly, to be able to translate practical food chemistry related

  7. Design, System, Value: The Role of Problem-Solving and Critical Thinking Capabilities in Technology Education, as Perceived by Teachers

    Science.gov (United States)

    Schooner, Patrick; Nordlöf, Charlotta; Klasander, Claes; Hallström, Jonas

    2017-01-01

    The Organisation for Economic Co-operation and Development (OECD, 2013) defines its views on necessary skills for 21st century citizenship and life-long learning, advocating a generic skillset of literacy, numeracy, and problem-solving in technology-rich environments. Other sources also include critical thinking as a vital 21st Century skill.…

  8. Computer-Supported Collaborative Problem-Based Learning: An Instructional Design Architecture for Virtual Learning in Nursing Education.

    Science.gov (United States)

    Naidu, Som; Oliver, Mary

    1996-01-01

    Describes a course developed at the University of Southern Queensland (Australia) that used problem-based learning within a computer-supported collaborative environment to give undergraduate nursing students practice in developing decision-making skills. The use of computer-mediated communication is also discussed. (LRW)

  9. Approach to Classifying "Design" Drugs and New Potentially Dangerous Chemical Substances, with a Brief Review of the Problem

    Science.gov (United States)

    Asadullin, Azat R.; Galeeva, Elena Kh.; Achmetova, Elvina A.; Nikolaev, Ivan V.

    2016-01-01

    The urgency of this study has become vivid in the light of the growing problem of prevalence and use of new synthetic drug types. Lately there has been a tendency of expanding the range of psychologically active substances (PAS) used by addicts with the purpose of their illegal taking. The aim of this research is an attempt of systematizing and…

  10. Using a task analysis approach within a guided problem-solving model to design mathematical learning activities

    Directory of Open Access Journals (Sweden)

    Aneshkumar Maharaj

    2007-10-01

    Full Text Available The FET Curriculum Statements for Mathematics advocates that knowledge integrates theory, skills and values. This paper focuses on a guided problem-solving teaching model that provides a framework to do this. A task analysis approach is used within this  framework to illustrate how educators could frame mathematical questions based on the relevant mathematical content.

  11. Using a task analysis approach within a guided problem-solving model to design mathematical learning activities

    OpenAIRE

    Aneshkumar Maharaj

    2007-01-01

    The FET Curriculum Statements for Mathematics advocates that knowledge integrates theory, skills and values. This paper focuses on a guided problem-solving teaching model that provides a framework to do this. A task analysis approach is used within this  framework to illustrate how educators could frame mathematical questions based on the relevant mathematical content.

  12. Development of a test facility to evaluate the optimal design of BMPs for managing environmental problems at construction sites.

    Science.gov (United States)

    2012-06-01

    The following document is the final report for ALDOT Project 930655 which summarizes the design and : construction of the Auburn University Erosion and Sediment Control Testing Facility (AUESCTF) along : with several intermediatescale, f...

  13. Design

    DEFF Research Database (Denmark)

    Volf, Mette

    This publication is unique in its demystification and operationalization of the complex and elusive nature of the design process. The publication portrays the designer’s daily work and the creative process, which the designer is a part of. Apart from displaying the designer’s work methods...... and design parameters, the publication shows examples from renowned Danish design firms. Through these examples the reader gets an insight into the designer’s reality....

  14. Design of reactor protection systems for HTR plants generating electric power and process heat problems and solutions

    International Nuclear Information System (INIS)

    Craemer, B.; Dahm, H.; Spillekothen, H.G.

    1982-06-01

    The design basis of the reactor protection system (RPS) for HTR plants generating process heat and electric power is briefly described and some particularities of process heat plants are indicated. Some particularly important or exacting technical measuring positions for the RPS of a process heat HTR with 500 MWsub(th) power (PNP 500) are described and current R + D work explained. It is demonstrated that a particularly simple RPS can be realized in an HTR with modular design. (author)

  15. How the Elderly Can Use Scientific Knowledge to Solve Problems While Designing Toys: A Retrospective Analysis of the Design of a Working UFO

    Science.gov (United States)

    Chen, Mei-Yung; Hong, Jon-Chao; Hwang, Ming-Yueh; Wong, Wan-Tzu

    2013-01-01

    The venerable aphorism "an old dog cannot learn new tricks" implies that the elderly rarely learn anything new--in particular, scientific knowledge. On the basis of "learning by doing," the present study emphasized knowledge application (KA) as elderly subjects collaborated on the design of a toy flying saucer (UFO). Three…

  16. Modeling and Analysis of Wholesale Electricity Market Design. Understanding the Missing Money Problem. December 2013 - January 2015

    Energy Technology Data Exchange (ETDEWEB)

    Papalexopoulos, A. [ECCO International, Inc., San Francisco, CA (United States); Hansen, C. [ECCO International, Inc., San Francisco, CA (United States); Perrino, D. [ECCO International, Inc., San Francisco, CA (United States); Frowd, R. [ECCO International, Inc., San Francisco, CA (United States)

    2015-05-31

    This project examined the impact of renewable energy sources, which have zero incremental energy costs, on the sustainability of conventional generation. This “missing money” problem refers to market outcomes in which infra-marginal energy revenues in excess of operations and maintenance (O&M) costs are systematically lower than the amortized costs of new entry for a marginal generator. The problem is caused by two related factors: (1) conventional generation is dispatched less, and (2) the price that conventional generation receives for its energy is lower. This lower revenue stream may not be sufficient to cover both the variable and fixed costs of conventional generation. In fact, this study showed that higher wind penetrations in the Electric Reliability Council of Texas (ERCOT) system could cause many conventional generators to become uneconomic.

  17. MINLP-based Analytic Hierarchy Process to simplify multi-objective problems: Application to the design of biofuels supply chains using on field surveys

    OpenAIRE

    Wheeler, Jonathan; Caballero, José A.; Ruiz-Femenia, Rubén; Guillén Gosálbez, Gonzalo; Mele, Fernando D.

    2017-01-01

    Multi-objective optimization (MOO) is widely used in engineering systems design and planning. The solution of a MOO problem leads to a set of efficient points (Pareto set) from which decision-makers should identify the one that best fits their preferences. Generating this set requires large computational efforts, and the post-optimal analysis of the solutions becomes difficult as the number of objectives increases. This work introduces an approach based on the Analytic Hierarchy Process (AHP)...

  18. Problem of probabilistic calculation of the design on linearly and non-linearly deformable basis with casual parameters

    Directory of Open Access Journals (Sweden)

    Mkrtychev Oleg Vartanovich

    Full Text Available In the article the problem of calculation of a construction basis system in case of earthquake is considered taking into account casual properties of basis soil in various points of the soil body. As a stochastic function in the calculation of linearly deformable basis, the deformation module, which accepts different values in the direction x, y, z, was chosen. In the calculation of the system on non-linearly deformable basis as incidentally distributed sizes the following parameters were accepted: deformation module, shear modulus, specific adhesion, angle of internal friction. The authors of the article offer to consider initial seismic influence in the form of casual stationary process. In order to solve such problems modern software systems are proposed that solve differential equations of motion via direct integration with explicit schemes. The calculation in this case will be held on the synthesized accelerograms. A short review of the task solution of the beam lying on elastic basis, which was received by D.N. Sobolev at casual distribution of pastel coefficient in the direction x, is provided in article. In order to define the objective, D.N. Sobolev gives expressions for a population mean and correlation function of stochastic function. As a result of the task solution population means and dispersions of function of movements and its derivatives were received. The problem formulation considered in the article is more complicated, but at the same time important from a practical standpoint.

  19. Placental complications after a previous cesarean section

    OpenAIRE

    Milošević Jelena; Lilić Vekoslav; Tasić Marija; Radović-Janošević Dragana; Stefanović Milan; Antić Vladimir

    2009-01-01

    Introduction The incidence of cesarean section has been rising in the past 50 years. With the increased number of cesarean sections, the number of pregnancies with the previous cesarean section rises as well. The aim of this study was to establish the influence of the previous cesarean section on the development of placental complications: placenta previa, placental abruption and placenta accreta, as well as to determine the influence of the number of previous cesarean sections on the complic...

  20. DIGIT. A digital filter design programme and its application to mains frequency interference rejection and other smoothing problems

    International Nuclear Information System (INIS)

    Knowles, J.B.

    1975-05-01

    Thermocouple measurements in heat transfer experiments on AC powered heat transfer rigs are often subject to an unacceptable level of grid frequency induced interference. A very narrow bandstop digital filter is proposed which effectively eliminates such nominal 50 Hz interference as well as its odd harmonics. The operation of digital filters, and the similarities with their analogue counterparts are explained in this report - partly written as a guide to designing digital filters. Listings and operating instructions of a FORTRAN IV computer programme (DIGIT) for designing: low pass, bandpass, bandstop and high pass digital filters are presented. The same FORTRAN programme also enables the designer to assess the effect of reductions in computer word-length on a filter's frequency response and its output noise. These calculations are required in order to specify the minimum word-length necessary for a satisfactory engineering realization on a mini or micro computer. (U.K.)

  1. Global sensitivity analysis of computer-aided molecular design problem for the development of novel working fluids for power cycles

    DEFF Research Database (Denmark)

    Frutiger, Jerome; Abildskov, Jens; Sin, Gürkan

    2016-01-01

    study involving the design of a working fluid for an Organic Ranking Cycle (ORC) design for power generation. Morris Screening is found to be favorable over Monte Carlo based standard regression. Monte Carlo based standard regression cannot be applied, because the current model cannot be sufficiently...... linearized. For Morris Screening techniques the critical temperature, the critical pressure and the acentric factor of the working fluid has been identified as the target properties with the highest sensitivity to the net power output of the cycle....

  2. A Comprehensive Solution of the Problems of Ensuring the Strength of Gas Turbine Engine Compressor at the Design Stage

    Science.gov (United States)

    Vedeneev, V. V.; Kolotnikov, M. E.; Mossakovskii, P. A.; Kostyreva, L. A.; Abdukhakimov, F. A.; Makarov, P. V.; Pyhalov, A. A.; Dudaev, M. A.

    2018-01-01

    In this paper we present a complex numerical workflow for analysis of blade flutter and high-amplitude resonant oscillations, impenetrability of casing if the blade is broken off, and the rotor reaction to the blade detachment and following misbalance, with the assessment of a safe flight possibility at the auto-rotation regime. All the methods used are carefully verified by numerical convergence study and correlations with experiments. The use of the workflow developed significantly improves the efficiency of the design process of modern jet engine compressors. It ensures a significant reduction of time and cost of the compressor design with the required level of strength and durability.

  3. Experimental Designs and the 'Emotion Stimulus Critique': Hidden Problems and Potential Solutions in the Study of Emotion.

    Science.gov (United States)

    Pascual-Leone, Antonio; Herpertz, Sabine C; Kramer, Ueli

    2016-01-01

    Emotional experience is increasingly being measured using experimental tasks, but the stimuli used are often only proxies for the emotion being studied. Stimuli are intended to evoke a distinct emotional experience, but certain designs fail to adequately control for the actual experience in question. In this methodological paper, we review designs used in clinical psychology aimed at measuring emotion and develop the argument of the 'emotion stimulus critique'. Designs of neuroimaging studies on emotion in this context are given preference. We argue that studies often concentrate on standardization of the stimulus material (i.e. words, images, and movies) for eliciting an emotional experience, whereas standardization of the actual participant's experience is seldom performed. Our proposal discusses the use of standardized stimuli in experimental designs and contrasts this with the necessity of controlling for a participant's unique emotional response. We highlight the importance of each participant's 'inner metric', i.e. the individual's experiential anchor, which needs to be taken into account when examining the emotional correlates of psychiatric disorders or psychotherapeutic change. Implications of the emotion stimulus critique for research are discussed within the context of psychology, particularly clinical psychology and psychotherapy. © 2015 S. Karger AG, Basel.

  4. Problem-Centered Design and Personal Teaching Style: An Exploratory Study of Youguang Tu's Course on Philosophy of Education

    Science.gov (United States)

    Lei, Hongde

    2016-01-01

    Youguang Tu is a contemporary Chinese philosopher of education. His course on philosophy of education had a significant impact on his students. This exploratory study examines how Tu designed and taught this course. Ultimately, there are two reasons why Tu's course had such a significant influence on his students. The first is that Tu used…

  5. Designing E-learning Model to Learn About Transportation Management System to Support Supply Chain Management with Simulation Problems

    OpenAIRE

    Wiyono, Didiek Sri; Pribadi, Sidigdoyo; Permana, Ryan

    2011-01-01

    Focus of this research is designing Transportation Management System (TMS) as e-learning media for logistic education. E-learning is the use of Internet technologies to enhance knowledge and performance. E-learning technologies offer learners control over content, learning sequence, pace of learning, time, and often media, allowing them to tailor their experiences to meet their personal learning objectives. E-learning appears to be at least as effective as classical lectures. Students do not ...

  6. Periodontal Research: Basics and beyond ? Part I (Defining the research problem, study design and levels of evidence)

    OpenAIRE

    Avula, Haritha; Pandey, Ruchi; Bolla, Vijayalakshmi; Rao, Harika; Avula, Jaya Kumar

    2013-01-01

    Research in the field of periodontology has witnessed a tremendous upsurge in the last two decades unveiling newer innovations in techniques, methodologies, and material science. The recent focus in periodontal research is an evidence-based approach which offers a bridge from science to clinical practice. This three part review series intends to take a reader through a maze of periodontal research, unraveling and simplifying various issues in the design, conduct and interpretation of various ...

  7. Linear and complex analysis problem

    CERN Document Server

    Nikolski, Nikolai

    1994-01-01

    The 2-volume book is an updated, reorganized and considerably enlarged version of the previous edition of the Research Problem Book in Analysis (LNM 1043), a collection familiar to many analysts, that has sparked off much research. This new edition, created in a joint effort by a large team of analysts, is, like its predecessor, a collection of unsolved problems of modern analysis designed as informally written mini-articles, each containing not only a statement of a problem but also historical and methodological comments, motivation, conjectures and discussion of possible connections, of plausible approaches as well as a list of references. There are now 342 of these mini- articles, almost twice as many as in the previous edition, despite the fact that a good deal of them have been solved!

  8. Linear and complex analysis problem

    CERN Document Server

    Nikolski, Nikolai

    1994-01-01

    The 2-volume-book is an updated, reorganized and considerably enlarged version of the previous edition of the Research Problem Book in Analysis (LNM 1043), a collection familiar to many analysts, that has sparked off much research. This new edition, created in a joint effort by a large team of analysts, is, like its predecessor, a collection of unsolved problems of modern analysis designed as informally written mini-articles, each containing not only a statement of a problem but also historical and metho- dological comments, motivation, conjectures and discussion of possible connections, of plausible approaches as well as a list of references. There are now 342 of these mini- articles, almost twice as many as in the previous edition, despite the fact that a good deal of them have been solved!

  9. Preoperative screening: value of previous tests.

    Science.gov (United States)

    Macpherson, D S; Snow, R; Lofgren, R P

    1990-12-15

    To determine the frequency of tests done in the year before elective surgery that might substitute for preoperative screening tests and to determine the frequency of test results that change from a normal value to a value likely to alter perioperative management. Retrospective cohort analysis of computerized laboratory data (complete blood count, sodium, potassium, and creatinine levels, prothrombin time, and partial thromboplastin time). Urban tertiary care Veterans Affairs Hospital. Consecutive sample of 1109 patients who had elective surgery in 1988. At admission, 7549 preoperative tests were done, 47% of which duplicated tests performed in the previous year. Of 3096 previous results that were normal as defined by hospital reference range and done closest to the time of but before admission (median interval, 2 months), 13 (0.4%; 95% CI, 0.2% to 0.7%), repeat values were outside a range considered acceptable for surgery. Most of the abnormalities were predictable from the patient's history, and most were not noted in the medical record. Of 461 previous tests that were abnormal, 78 (17%; CI, 13% to 20%) repeat values at admission were outside a range considered acceptable for surgery (P less than 0.001, frequency of clinically important abnormalities of patients with normal previous results with those with abnormal previous results). Physicians evaluating patients preoperatively could safely substitute the previous test results analyzed in this study for preoperative screening tests if the previous tests are normal and no obvious indication for retesting is present.

  10. Sensitivity analysis of Computer-aided molecular design problem for the development of novel working fluids for power cycles

    DEFF Research Database (Denmark)

    Frutiger, Jerome; Abildskov, Jens; Sin, Gürkan

    problem. It integrates both a system model for the ORC and property models,such as GC+-based models for estimation of pure component properties, Peng-Robinson equation of state for estimationof enthalpy, entropy, etc.. The system consists of coupled mass and energy balances for a pump, a condenser......In recent years there is a large availability of low-temperature heat sources in different applications such as waste heat in chemical industries and refrigeration plants as well as renewable energy sources suchas biomass combustion, geothermal and solar heat sources. Power cycles are an important...... technical tool to convert this waste heat into usable energy. So far the low-temperature heat cannot be utilized efficiently for electricity generation.In order to optimize the heat transfer process and the power generation, the influence of the working fluid, the cycledesigns and the operating conditions...

  11. Automatic electromagnetic valve for previous vacuum

    International Nuclear Information System (INIS)

    Granados, C. E.; Martin, F.

    1959-01-01

    A valve which permits the maintenance of an installation vacuum when electric current fails is described. It also lets the air in the previous vacuum bomb to prevent the oil ascending in the vacuum tubes. (Author)

  12. A Multirate Control Strategy to the Slow Sensors Problem: An Interactive Simulation Tool for Controller Assisted Design

    Science.gov (United States)

    Salt, Julián; Cuenca, Ángel; Palau, Francisco; Dormido, Sebastián

    2014-01-01

    In many control applications, the sensor technology used for the measurement of the variable to be controlled is not able to maintain a restricted sampling period. In this context, the assumption of regular and uniform sampling pattern is questionable. Moreover, if the control action updating can be faster than the output measurement frequency in order to fulfill the proposed closed loop behavior, the solution is usually a multirate controller. There are some known aspects to be careful of when a multirate system (MR) is going to be designed. The proper multiplicity between input-output sampling periods, the proper controller structure, the existence of ripples and others issues need to be considered. A useful way to save time and achieve good results is to have an assisted computer design tool. An interactive simulation tool to deal with MR seems to be the right solution. In this paper this kind of simulation application is presented. It allows an easy understanding of the performance degrading or improvement when changing the multirate sampling pattern parameters. The tool was developed using Sysquake, a Matlab-like language with fast execution and powerful graphic facilities. It can be delivered as an executable. In the paper a detailed explanation of MR treatment is also included and the design of four different MR controllers with flexible structure to be adapted to different schemes will also be presented. The Smith's predictor in these MR schemes is also explained, justified and used when time delays appear. Finally some interesting observations achieved using this interactive tool are included. PMID:24583971

  13. Benchmarking B-Cell Epitope Prediction for the Design of Peptide-Based Vaccines: Problems and Prospects

    Directory of Open Access Journals (Sweden)

    Salvador Eugenio C. Caoili

    2010-01-01

    Full Text Available To better support the design of peptide-based vaccines, refinement of methods to predict B-cell epitopes necessitates meaningful benchmarking against empirical data on the cross-reactivity of polyclonal antipeptide antibodies with proteins, such that the positive data reflect functionally relevant cross-reactivity (which is consistent with antibody-mediated change in protein function and the negative data reflect genuine absence of cross-reactivity (rather than apparent absence of cross-reactivity due to artifactual masking of B-cell epitopes in immunoassays. These data are heterogeneous in view of multiple factors that complicate B-cell epitope prediction, notably physicochemical factors that define key structural differences between immunizing peptides and their cognate proteins (e.g., unmatched electrical charges along the peptide-protein sequence alignments. If the data are partitioned with respect to these factors, iterative parallel benchmarking against the resulting subsets of data provides a basis for systematically identifying and addressing the limitations of methods for B-cell epitope prediction as applied to vaccine design.

  14. Concomitant and previous osteoporotic vertebral fractures.

    Science.gov (United States)

    Lenski, Markus; Büser, Natalie; Scherer, Michael

    2017-04-01

    Background and purpose - Patients with osteoporosis who present with an acute onset of back pain often have multiple fractures on plain radiographs. Differentiation of an acute osteoporotic vertebral fracture (AOVF) from previous fractures is difficult. The aim of this study was to investigate the incidence of concomitant AOVFs and previous OVFs in patients with symptomatic AOVFs, and to identify risk factors for concomitant AOVFs. Patients and methods - This was a prospective epidemiological study based on the Registry of Pathological Osteoporotic Vertebral Fractures (REPAPORA) with 1,005 patients and 2,874 osteoporotic vertebral fractures, which has been running since February 1, 2006. Concomitant fractures are defined as at least 2 acute short-tau inversion recovery (STIR-) positive vertebral fractures that happen concomitantly. A previous fracture is a STIR-negative fracture at the time of initial diagnostics. Logistic regression was used to examine the influence of various variables on the incidence of concomitant fractures. Results - More than 99% of osteoporotic vertebral fractures occurred in the thoracic and lumbar spine. The incidence of concomitant fractures at the time of first patient contact was 26% and that of previous fractures was 60%. The odds ratio (OR) for concomitant fractures decreased with a higher number of previous fractures (OR =0.86; p = 0.03) and higher dual-energy X-ray absorptiometry T-score (OR =0.72; p = 0.003). Interpretation - Concomitant and previous osteoporotic vertebral fractures are common. Risk factors for concomitant fractures are a low T-score and a low number of previous vertebral fractures in cases of osteoporotic vertebral fracture. An MRI scan of the the complete thoracic and lumbar spine with STIR sequence reduces the risk of under-diagnosis and under-treatment.

  15. Design

    DEFF Research Database (Denmark)

    Jensen, Ole B.; Pettiway, Keon

    2017-01-01

    by designers, planners, etc. (staging from above) and mobile subjects (staging from below). A research agenda for studying situated practices of mobility and mobilities design is outlined in three directions: foci of studies, methods and approaches, and epistemologies and frames of thinking. Jensen begins......In this chapter, Ole B. Jensen takes a situational approach to mobilities to examine how ordinary life activities are structured by technology and design. Using “staging mobilities” as a theoretical approach, Jensen considers mobilities as overlapping, actions, interactions and decisions...... with a brief description of how movement is studied within social sciences after the “mobilities turn” versus the idea of physical movement in transport geography and engineering. He then explains how “mobilities design” was derived from connections between traffic and architecture. Jensen concludes...

  16. The effectiveness of the Screening Inventory of Psychosocial Problems (SIPP) in cancer patients treated with radiotherapy: design of a cluster randomised controlled trial

    International Nuclear Information System (INIS)

    Braeken, Anna PBM; Lechner, Lilian; Gils, Francis CJM van; Houben, Ruud MA; Eekers, Daniëlle; Ambergen, Ton; Kempen, Gertrudis IJM

    2009-01-01

    The Screening Inventory of Psychosocial Problems (SIPP) is a short, validated self-reported questionnaire to identify psychosocial problems in Dutch cancer patients. The one-page 24-item questionnaire assesses physical complaints, psychological complaints and social and sexual problems. Very little is known about the effects of using the SIPP in consultation settings. Our study aims are to test the hypotheses that using the SIPP (a) may contribute to adequate referral to relevant psychosocial caregivers, (b) should facilitate communication between radiotherapists and cancer patients about psychosocial distress and (c) may prevent underdiagnosis of early symptoms reflecting psychosocial problems. This paper presents the design of a cluster randomised controlled trial (CRCT) evaluating the effectiveness of using the SIPP in cancer patients treated with radiotherapy. A CRCT is developed using a Solomon four-group design (two intervention and two control groups) to evaluate the effects of using the SIPP. Radiotherapists, instead of cancer patients, are randomly allocated to the experimental or control groups. Within these groups, all included cancer patients are randomised into two subgroups: with and without pre-measurement. Self-reported assessments are conducted at four times: a pre-test at baseline before the first consultation and a post-test directly following the first consultation, and three and 12 months after baseline measurement. The primary outcome measures are the number and types of referrals of cancer patients with psychosocial problems to relevant (psychosocial) caregivers. The secondary outcome measures are patients' satisfaction with the radiotherapist-patient communication, psychosocial distress and quality of life. Furthermore, a process evaluation will be carried out. Data of the effect-evaluation will be analysed according to the intention-to-treat principle and data regarding the types of referrals to health care providers and patient

  17. Design

    DEFF Research Database (Denmark)

    Volf, Mette

    Design - proces & metode iBog®  er enestående i sit fokus på afmystificering og operationalisering af designprocessens flygtige og komplekse karakter. Udgivelsen går bag om designerens daglige arbejde og giver et indblik i den kreative skabelsesproces, som designeren er en del af. Udover et bredt...... indblik i designerens arbejdsmetoder og designparametre giver Design - proces & metode en række eksempler fra anerkendte designvirksomheder, der gør det muligt at komme helt tæt på designerens virkelighed....

  18. Lost and misplaced items and assistive devices in nursing homes: Identifying problems and technological opportunities through participatory design research.

    Science.gov (United States)

    Oude Weernink, C E; Sweegers, L; Relou, L; van der Zijpp, T J; van Hoof, J

    2018-02-06

    Modern healthcare, including nursing home care, goes together with the use of technologies to support treatment, the provision of care and daily activities. The challenges concerning the implementation of such technologies are numerous. One of these emerging technologies are location technologies (RTLS or Real-Time Location Systems). that can be utilized in the nursing home for monitoring the use and location of assets. This paper describes a participatory design study of RTLS based on context mapping, conducted in two nursing home organizations. Rather than investigating the technological possibilities, this study investigates the needs and wishes from the perspective of the care professional. The study identified semantic themes that relate to the practicalities of lost and misplaced items in the nursing home, as well as latent themes that cover the wishes regarding technology in the nursing homes. The organizational culture and building typology may play a role in losing items. The participants in this study indicated that RTLS can provide a solution to some of the challenges that they encounter in the workplace. However, the implementation of new technologies should be done with care and should be integrated into existing ICT systems in order to minimize additional training and posing a burden on the workload.

  19. Design

    Science.gov (United States)

    Buchanan, Richard; Cross, Nigel; Durling, David; Nelson, Harold; Owen, Charles; Valtonen, Anna; Boling, Elizabeth; Gibbons, Andrew; Visscher-Voerman, Irene

    2013-01-01

    Scholars representing the field of design were asked to identify what they considered to be the most exciting and imaginative work currently being done in their field, as well as how that work might change our understanding. The scholars included Richard Buchanan, Nigel Cross, David Durling, Harold Nelson, Charles Owen, and Anna Valtonen. Scholars…

  20. Design

    DEFF Research Database (Denmark)

    Jensen, Ole B.; Pettiway, Keon

    2017-01-01

    In this chapter, Ole B. Jensen takes a situational approach to mobilities to examine how ordinary life activities are structured by technology and design. Using “staging mobilities” as a theoretical approach, Jensen considers mobilities as overlapping, actions, interactions and decisions by desig......In this chapter, Ole B. Jensen takes a situational approach to mobilities to examine how ordinary life activities are structured by technology and design. Using “staging mobilities” as a theoretical approach, Jensen considers mobilities as overlapping, actions, interactions and decisions...... by designers, planners, etc. (staging from above) and mobile subjects (staging from below). A research agenda for studying situated practices of mobility and mobilities design is outlined in three directions: foci of studies, methods and approaches, and epistemologies and frames of thinking. Jensen begins...... with a brief description of how movement is studied within social sciences after the “mobilities turn” versus the idea of physical movement in transport geography and engineering. He then explains how “mobilities design” was derived from connections between traffic and architecture. Jensen concludes...

  1. Balance and bilateral skills of selected previously disadvantaged ...

    African Journals Online (AJOL)

    Balance and bilateral skills of selected previously disadvantaged children aged 9 to 12 years. Eileen K Africa, Karel J Van Deventer. Abstract. The main aim of the study was to design an appropriate motor skills development programme that could be implemented in any primary school to improve the fundamental motor ...

  2. The job satisfaction of principals of previously disadvantaged schools

    African Journals Online (AJOL)

    The aim of this study was to identify influences on the job satisfaction of previously disadvantaged school principals in North-West Province. Evans's theory of job satisfaction, morale and motivation was useful as a conceptual framework. A mixedmethods explanatory research design was important in discovering issues with ...

  3. Previously infertile couples and the newborn intensive care unit.

    Science.gov (United States)

    Lind, R F; Pruitt, R L; Greenfeld, D

    1989-05-01

    Having a newborn child admitted to a newborn intensive care unit can be a traumatic experience for parents; however, parents who previously have been infertile face unique problems in coping with this situation. The authors discuss the difficulties parents must overcome in resolving their crises and in developing a good relationship with their child, or, in some cases, coming to terms with the child's death or ongoing disability. In addition, the authors offer suggestions for effective social work intervention.

  4. INTRODUCTION Previous reports have documented a high ...

    African Journals Online (AJOL)

    pregnancy if they were married, educated, had dental insurance, previously used dental services when not pregnant, or had knowledge about the possible connection between oral health and pregnancy outcome8. The purpose of this study was to explore the factors determining good oral hygiene among pregnant women ...

  5. Empowerment perceptions of educational managers from previously ...

    African Journals Online (AJOL)

    The perceptions of educational manag ers from previously disadvantaged primary and high schools in the Nelson Mandela Metropole regarding the issue of empowerment are outlined and the perceptions of educational managers in terms of various aspects of empowerment at different levels reflected. A literature study ...

  6. Management of choledocholithiasis after previous gastrectomy.

    Science.gov (United States)

    Anwer, S; Egan, R; Cross, N; Guru Naidu, S; Somasekar, K

    2017-09-01

    Common bile duct stones in patients with a previous gastrectomy can be a technical challenge because of the altered anatomy. This paper presents the successful management of two such patients using non-traditional techniques as conventional endoscopic retrograde cholangiopancreatography was not possible.

  7. Laboratory Grouping Based on Previous Courses.

    Science.gov (United States)

    Doemling, Donald B.; Bowman, Douglas C.

    1981-01-01

    In a five-year study, second-year human physiology students were grouped for laboratory according to previous physiology and laboratory experience. No significant differences in course or board examination performance were found, though correlations were found between predental grade-point averages and grouping. (MSE)

  8. Calculus problems

    CERN Document Server

    Baronti, Marco; van der Putten, Robertus; Venturi, Irene

    2016-01-01

    This book, intended as a practical working guide for students in Engineering, Mathematics, Physics, or any other field where rigorous calculus is needed, includes 450 exercises. Each chapter starts with a summary of the main definitions and results, which is followed by a selection of solved exercises accompanied by brief, illustrative comments. A selection of problems with indicated solutions rounds out each chapter. A final chapter explores problems that are not designed with a single issue in mind but instead call for the combination of a variety of techniques, rounding out the book’s coverage. Though the book’s primary focus is on functions of one real variable, basic ordinary differential equations (separation of variables, linear first order and constant coefficients ODEs) are also discussed. The material is taken from actual written tests that have been delivered at the Engineering School of the University of Genoa. Literally thousands of students have worked on these problems, ensuring their real-...

  9. Development of eHOME, a Mobile Instrument for Reporting, Monitoring, and Consulting Drug-Related Problems in Home Care: Human-Centered Design Study.

    Science.gov (United States)

    Dijkstra, Nienke Elske; Sino, Carolina Geertruida Maria; Heerdink, Eibert Rob; Schuurmans, Marieke Joanna

    2018-03-07

    Home care patients often use many medications and are prone to drug-related problems (DRPs). For the management of problems related to drug use, home care could add to the multidisciplinary expertise of general practitioners (GPs) and pharmacists. The home care observation of medication-related problems by home care employees (HOME)-instrument is paper-based and assists home care workers in reporting potential DRPs. To facilitate the multiprofessional consultation, a digital report of DRPs from the HOME-instrument and digital monitoring and consulting of DRPs between home care and general practices and pharmacies is desired. The objective of this study was to develop an electronic HOME system (eHOME), a mobile version of the HOME-instrument that includes a monitoring and a consulting system for primary care. The development phase of the Medical Research Council (MRC) framework was followed in which an iterative human-centered design (HCD) approach was applied. The approach involved a Delphi round for the context of use and user requirements analysis of the digital HOME-instrument and the monitoring and consulting system followed by 2 series of pilots for testing the usability and redesign. By using an iterative design approach and by involving home care workers, GPs, and pharmacists throughout the process as informants, design partners, and testers, important aspects that were crucial for system realization and user acceptance were revealed. Through the report webpage interface, which includes the adjusted content of the HOME-instrument and added home care practice-based problems, home care workers can digitally report observed DRPs. Furthermore, it was found that the monitoring and consulting webpage interfaces enable digital consultation between home care and general practices and pharmacies. The webpages were considered convenient, clear, easy, and usable. By employing an HCD approach, the eHOME-instrument was found to be an easy-to-use system. The systematic

  10. Design of a randomized controlled trial on the effects of Counseling of mental health problems by Occupational Physicians on return to work: the CO-OP-study

    Directory of Open Access Journals (Sweden)

    van Mechelen Willem

    2007-07-01

    Full Text Available Abstract Background Mental health problems often lead to prolonged sick leave. In primary care, the usual approach towards these patients was the advice to take rest and not return to work before all complaints had disappeared. When complaints persist, these patients are often referred to psychologists from primary and specialized secondary care. As an alternative, ways have been sought to activate the Dutch occupational physician (OP in primary care. Early 2000, the Dutch Association of Occupational Physicians (NVAB published a guideline concerning the management by OPs of employees with mental health problems. The guideline received positive reactions from employees, employers and Dutch OPs. This manuscript describes the design of a study, which aims to assess the effects of the guideline, compared with usual care. Methods/Design In a randomized controlled trial (RCT, subjects in the intervention group were treated according to the guideline. The control group received usual care, with minimal involvement of the OP and easy access to a psychologist. Subjects were recruited from two Dutch police departments. The primary outcomes of the study are return to work and treatment satisfaction by the employee, employer, and OP. A secondary outcome is cost-effectiveness of the intervention, compared with usual care. Furthermore, prognostic measures are taken into account as potential confounders. A process evaluation will be done by means of performance indicators, based on the guideline. Discussion In this pragmatic trial, effectiveness instead of efficacy is studied. We will evaluate what is possible in real clinical practice, rather than under ideal circumstances. Many requirements for a high quality trial are being met. Results of this study will contribute to treatment options in occupational health practice for employees on sick leave due to mental health problems. Additionally, they may contribute to new and better-suited guidelines and stepped

  11. Previously unknown organomagnesium compounds in astrochemical context

    OpenAIRE

    Ruf, Alexander

    2018-01-01

    We describe the detection of dihydroxymagnesium carboxylates (CHOMg) in astrochemical context. CHOMg was detected in meteorites via ultrahigh-resolving chemical analytics and represents a novel, previously unreported chemical class. Thus, chemical stability was probed via quantum chemical computations, in combination with experimental fragmentation techniques. Results propose the putative formation of green-chemical OH-Grignard-type molecules and triggered fundamental questions within chemica...

  12. [Placental complications after a previous cesarean section].

    Science.gov (United States)

    Milosević, Jelena; Lilić, Vekoslav; Tasić, Marija; Radović-Janosević, Dragana; Stefanović, Milan; Antić, Vladimir

    2009-01-01

    The incidence of cesarean section has been rising in the past 50 years. With the increased number of cesarean sections, the number of pregnancies with the previous cesarean section rises as well. The aim of this study was to establish the influence of the previous cesarean section on the development of placental complications: placenta previa, placental abruption and placenta accreta, as well as to determine the influence of the number of previous cesarean sections on the complication development. The research was conducted at the Clinic of Gynecology and Obstetrics in Nis covering 10-year-period (from 1995 to 2005) with 32358 deliveries, 1280 deliveries after a previous cesarean section, 131 cases of placenta previa and 118 cases of placental abruption. The experimental groups was presented by the cases of placenta previa or placental abruption with prior cesarean section in obstetrics history, opposite to the control group having the same conditions but without a cesarean section in medical history. The incidence of placenta previa in the control group was 0.33%, opposite to the 1.86% incidence after one cesarean section (pcesarean sections and as high as 14.28% after three cesarean sections in obstetric history. Placental abruption was recorded as placental complication in 0.33% pregnancies in the control group, while its incidence was 1.02% after one cesarean section (pcesarean sections. The difference in the incidence of intrapartal hysterectomy between the group with prior cesarean section (0.86%) and without it (0.006%) shows a high statistical significance (pcesarean section is an important risk factor for the development of placental complications.

  13. Methodology based in the fuzzy logic for constructing the objective functions in optimization problems of nuclear fuel: application to the cells radial design

    International Nuclear Information System (INIS)

    Barragan M, A.M.; Martin del Campo M, C.; Palomera P, M.A.

    2005-01-01

    A methodology based on Fuzzy Logic for the construction of the objective function of the optimization problems of nuclear fuel is described. It was created an inference system that responds, in certain form, as a human expert when it has the task of qualifying different radial designs of fuel cells. Specifically it is detailed how an inference system based based on Fuzzy Logic that has five enter variables and one exit variable was built, which corresponds to the objective function for the radial design of a fuel cell for a BWR. The use of Fuzzy with Mat lab offered the visualization capacity of the exit variable in function of one or two enter variables at the same time. This allowed to build, in appropriate way, the combination of the inference rules and the membership functions of those diffuse sets used for each one of the enter variables. The obtained objective function was used in an optimization process based on Taboo search. The new methodology was proven for the design of a cell used in a fuel assemble of the Laguna Verde reactor obtaining excellent results. (Author)

  14. Ear Problems

    Science.gov (United States)

    ... Infants and Children Chest Pain, Acute Chest Pain, Chronic Cold and Flu Cough Diarrhea Ear Problems Elimination Problems Elimination Problems in Infants and Children Eye Problems Facial Swelling Feeding Problems in Infants ...

  15. Urination Problems

    Science.gov (United States)

    ... Infants and Children Chest Pain, Acute Chest Pain, Chronic Cold and Flu Cough Diarrhea Ear Problems Elimination Problems Elimination Problems in Infants and Children Eye Problems Facial Swelling Feeding Problems in Infants ...

  16. Executive Function in Previously Institutionalized Children.

    Science.gov (United States)

    Merz, Emily C; Harlé, Katia M; Noble, Kimberly G; McCall, Robert B

    2016-06-01

    In studies of children adopted from institutions, being raised in an institution has been associated consistently with an increased risk of persistent cognitive, academic, and social-emotional problems. These findings raise questions about the neurocognitive mechanisms that contribute to these negative outcomes. Theory and models based on studies of animals indicate that development of the prefrontal cortex (PFC) and executive function (EF) may be particularly susceptible to environmental influences during early childhood. In this article, we review recent studies of postinstitutionalized children that examined EF components such as inhibitory control, working memory, shifting, and planning. We then describe emerging research on the structure and function of the PFC. Converging evidence suggests both EF difficulties and alterations in development of the PFC following early institutionalization. We conclude by discussing possible explanations for these findings and implications for prevention and intervention, and by offering suggestions for ongoing research.

  17. A hybrid approach to solving the problem of design of nuclear fuel cells; Un enfoque hibrido para la solucion del problema del diseno de celdas de combustible nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Montes T, J. L.; Perusquia del C, R.; Ortiz S, J. J.; Castillo, A., E-mail: joseluis.montes@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2015-09-15

    An approach to solving the problem of fuel cell design for BWR power reactor is presented. For this purpose the hybridization of a method based in heuristic knowledge rules called S15 and the advantages of a meta-heuristic method is proposed. The synergy of potentialities of both techniques allows finding solutions of more quality. The quality of each solution is obtained through a multi-objective function formed from the main cell parameters that are provided or obtained during the simulation with the CASMO-4 code. To evaluate this alternative of solution nuclear fuel cells of reference of nuclear power plant of Laguna Verde were used. The results show that in a systematic way the results improve when both methods are coupled. As a result of the hybridization process of the mentioned techniques an improvement is achieved in a range of 2% with regard to the achieved results in an independent way by the S15 method. (Author)

  18. A Review of Common Problems in Design and Installation of Water Spray Cooling and Low Expansion Foam System to Protect Storage Tanks Containing Hydrocarbons Against Fires

    Directory of Open Access Journals (Sweden)

    I. Alimohammadi

    2015-11-01

    Full Text Available Tank fires are rare but carry significant potential risk to life and property. For this reason fire protection of tanks is critical. Fixed Low expansion foam and water spray cooling systems are one of the most effective and economical ways to reduce damages to a tank from fire. Such systems are currently installed in many companies but are not effective enough and require involvement of firefighters which in turn threaten their lives. This paper studies in a systematic way the problems of foam and cooling systems currently installed in a few domestic companies which operate storage tanks with focus on floating and fixed roof atmospheric tanks containing hydrocarbons and offers possible solutions for more efficient installation, design and operation of such systems.

  19. A Review of Common Problems in Design and Installation of Water Spray Cooling and Low Expansion Foam System to Protect Storage Tanks Containing Hydrocarbons Against Fires

    Directory of Open Access Journals (Sweden)

    Iraj Alimohammadi

    2015-12-01

    Full Text Available Tank fires are rare but carry significant potential risk to life and property. For this reason fire protection of tanks is critical. Fixed Low expansion foam and water spray cooling systems are one of the most effective and economical ways to reduce damages to a tank from fire. Such systems are currently installed in many companies but are not effective enough and require involvement of firefighters which in turn threaten their lives. This paper studies in a systematic way the problems of foam and cooling systems currently installed in a few domestic companies which operate storage tanks with focus on floating and fixed roof atmospheric tanks containing hydrocarbons and offers possible solutions for more efficient installation, design and operation of such systems.

  20. Books average previous decade of economic misery.

    Science.gov (United States)

    Bentley, R Alexander; Acerbi, Alberto; Ormerod, Paul; Lampos, Vasileios

    2014-01-01

    For the 20(th) century since the Depression, we find a strong correlation between a 'literary misery index' derived from English language books and a moving average of the previous decade of the annual U.S. economic misery index, which is the sum of inflation and unemployment rates. We find a peak in the goodness of fit at 11 years for the moving average. The fit between the two misery indices holds when using different techniques to measure the literary misery index, and this fit is significantly better than other possible correlations with different emotion indices. To check the robustness of the results, we also analysed books written in German language and obtained very similar correlations with the German economic misery index. The results suggest that millions of books published every year average the authors' shared economic experiences over the past decade.

  1. Induced vaginal birth after previous caesarean section

    Directory of Open Access Journals (Sweden)

    Akylbek Tussupkaliyev

    2016-11-01

    Full Text Available Introduction The rate of operative birth by Caesarean section is constantly rising. In Kazakhstan, it reaches 27 per cent. Research data confirm that the percentage of successful vaginal births after previous Caesarean section is 50–70 per cent. How safe the induction of vaginal birth after Caesarean (VBAC remains unclear. Methodology The studied techniques of labour induction were amniotomy of the foetal bladder with the vulsellum ramus, intravaginal administration of E1 prostaglandin (Misoprostol, and intravenous infusion of Oxytocin-Richter. The assessment of rediness of parturient canals was conducted by Bishop’s score; the labour course was assessed by a partogram. The effectiveness of labour induction techniques was assessed by the number of administered doses, the time of onset of regular labour, the course of labour and the postpartum period and the presence of complications, and the course of the early neonatal period, which implied the assessment of the child’s condition, described in the newborn development record. The foetus was assessed by medical ultrasound and antenatal and intranatal cardiotocography (CTG. Obtained results were analysed with SAS statistical processing software. Results The overall percentage of successful births with intravaginal administration of Misoprostol was 93 per cent (83 of cases. This percentage was higher than in the amniotomy group (relative risk (RR 11.7 and was similar to the oxytocin group (RR 0.83. Amniotomy was effective in 54 per cent (39 of cases, when it induced regular labour. Intravenous oxytocin infusion was effective in 94 per cent (89 of cases. This percentage was higher than that with amniotomy (RR 12.5. Conclusions The success of vaginal delivery after previous Caesarean section can be achieved in almost 70 per cent of cases. At that, labour induction does not decrease this indicator and remains within population boundaries.

  2. The design of the Dutch EASYcare study: a randomised controlled trial on the effectiveness of a problem-based community intervention model for frail elderly people [NCT00105378

    Directory of Open Access Journals (Sweden)

    van Achterberg Theo

    2005-10-01

    Full Text Available Abstract Background Because of their complex clinical presentations and needs frail elderly people require another approach than people who age without many complications. Several inpatient geriatric health services have proven effectiveness in frail persons. However, the wish to live independently and policies that promote independent living as an answer to population aging call for community intervention models for frail elderly people. Maybe models such as preventive home visits, comprehensive geriatric assessment, and intermediate care qualify, but their efficacy is controversial, especially in frail elderly persons living in the community. With the Dutch EASYcare Study Geriatric Intervention Programme (DGIP we developed a model to study effectiveness of problem based community intervention models in frail elderly people. Methods/Design DGIP is a community intervention model for frail elderly persons where the GP refers elderly patients with a problem in cognition, mood, behaviour, mobility, and nutrition. A geriatric specialist nurse applies a guideline-based intervention with a limited number of follow up visits. The intervention starts with the application of the EASYcare instrument for geriatric screening. The EASYcare instrument assesses (instrumental activities of daily life, cognition, mood, and includes a goal setting item. During the intervention the nurse regularly consults the referring GP and a geriatrician. Effects on functional performance (Groningen Activity Restriction Scale, health related quality of life (MOS-20, and carer burden (Zarit Burden Interview are studied in an observer blinded randomised controlled trial. 151 participants were randomised over two treatment arms – DGIP and regular care – using pseudo cluster randomisation. We are currently performing the follow up visits. These visits are planned three and six months after inclusion. Process measures and cost measures will be recorded. Intention to treat

  3. General design and main problems of a gas-heavy-water power reactor contained in a pressure vessel; Conception generale et principaux problemes d'un reacteur de puissance eau lourde-gaz contenu dans un caisson resistant

    Energy Technology Data Exchange (ETDEWEB)

    Roche, R.; Gaudez, J.C. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    In the framework of research carried out on a CO{sub 2}-cooled power reactor moderated by heavy water, the so-called 'pressure vessel' solution involves the total integration of the core, of the primary circuit (exchanges and blowers) and of the fuel handling machine inside a single, strong, sealed vessel made of pre-stressed concrete. A vertical design has been chosen: the handling 'attic' is placed above the core, the exchanges being underneath. This solution makes it possible to standardize the type of reactor which is moderated by heavy-water or graphite and cooled by a downward stream of carbon dioxide gas; it has certain advantages and disadvantages with respect to the pressure tube solution and these are considered in detail in this report. Extrapolation presents in particular.problems due specifically to the heavy water (for example its cooling,its purification, the balancing of the pressures of the heavy water and of the gas, the assembling of the internal structures, the height of the attic, etc. (authors) [French] Dans le cadre des etudes d'un reacteur de puissance modere a l'eau lourde et refroidi-au gaz carbonique, la solution dite 'en caisson' consiste en une integration totale du coeur, du circuit primaire (echangeurs et soufflantes) et du dispositif de manutention du combustible a l'interieur d'un meme caisson etanche et resistant en beton precontraint. La disposition envisagee est verticale; le grenier de manutention est dispose au-dessus du coeur, les echangeurs en dessous. Cette solution, qui permet d'uniformiser les types de reacteurs moderes a l'eau lourde ou au graphite et refroidis par une circulation descendante de gaz carbonique presente, par rapport a la solution a tube de force, des avantages et des inconvenients qui sont analyses dans cette etude. L'extrapolation pose, en particulier, des problemes specifiques a l'eau lourde (tels que son refroidissement, son epuration

  4. Stimuli previously associated with reinforcement mitigate resurgence.

    Science.gov (United States)

    Craig, Andrew R; Browning, Kaitlyn O; Shahan, Timothy A

    2017-09-01

    Resurgence refers to the recurrence of an extinguished target behavior following subsequent suspension of alternative reinforcement. Delivery of reinforcers during extinction of alternative behavior has been shown to mitigate resurgence. The present experiment aimed to determine whether delivering stimuli associated with reinforcers during resurgence testing similarly mitigates resurgence. Three groups of rats pressed target levers for food according to variable-interval 15-s schedules during Phase 1. In Phase 2, lever pressing was extinguished, and an alternative nose-poke response produced alternative reinforcement according to a variable-interval 15-s schedule. Food reinforcement was always associated with illumination of the food aperture and an audible click from the pellet dispenser during Phases 1 and 2. Phase 3 treatments differed between groups. For one group, nose poking continued to produce food and food-correlated stimuli. Both of these consequences were suspended for a second group. Finally, nose poking produced food-correlated stimuli but not food for a third group. Target-lever pressing resurged in the group that received no consequences and in the group that received only food-correlated stimuli for nose poking. Resurgence, however, was smaller for the group that received food-correlated stimuli than for the group that received no consequences for nose poking. Target-lever pressing did not increase between phases in the group that continued to receive food and associated stimuli. Thus, delivery of stimuli associated with food reinforcement after suspension of food reduced but did not eliminate resurgence of extinguished lever pressing. These findings contribute to potential methodologies for preventing relapse of extinguished problem behavior in clinical settings. © 2017 Society for the Experimental Analysis of Behavior.

  5. Benefits and Challenges when Performing Robust Topology Optimization for Interior Acoustic Problems

    DEFF Research Database (Denmark)

    Christiansen, Rasmus Ellebæk; Jensen, Jakob Søndergaard; Lazarov, Boyan Stefanov

    The objective of this work is to present benets and challenges of using robust topology optimization techniques for minimizing the sound pressure in interior acoustic problems. The focus is on creating designs which maintain high performance under uniform spatial variations. This work takes offset...... in previous work considering topology optimization for interior acoustic problems, [1]. However in the previous work the robustness of the designs was not considered....

  6. Balance Problems

    Science.gov (United States)

    ... often, it could be a sign of a balance problem. Balance problems can make you feel unsteady. You may ... related injuries, such as a hip fracture. Some balance problems are due to problems in the inner ...

  7. Landscape and participation: construction of a PhD research problem and an analysis method. Towards the comparative analysis of participatory processes of landscape management projects design on a local scale in the Walloon region (Belgium)

    OpenAIRE

    Droeven, Emilie

    2007-01-01

    A preliminary reflection to the definition of a PhD research problem on the concepts of participation, landscape and project, led the student to be interested in the participatory processes of landscape management projects design, and in the inhabitants landscapes representations. The method includes the comparative analysis of local processes of projects design, and the direct observation of two Walloon landscape management projects design (investigation conducted with stakeholders implied i...

  8. [Population problem, comprehension problem].

    Science.gov (United States)

    Tallon, F

    1993-08-01

    Overpopulation of developing countries in general, and Rwanda in particular, is not just their problem but a problem for developed countries as well. Rapid population growth is a key factor in the increase of poverty in sub-Saharan Africa. Population growth outstrips food production. Africa receives more and more foreign food, economic, and family planning aid each year. The Government of Rwanda encourages reduced population growth. Some people criticize it, but this criticism results in mortality and suffering. One must combat this ignorance, but attitudes change slowly. Some of these same people find the government's acceptance of family planning an invasion of their privacy. Others complain that rich countries do not have campaigns to reduce births, so why should Rwanda do so? The rate of schooling does not increase in Africa, even though the number of children in school increases, because of rapid population growth. Education is key to improvements in Africa's socioeconomic growth. Thus, Africa, is underpopulated in terms of potentiality but overpopulated in terms of reality, current conditions, and possibilities of overexploitation. Africa needs to invest in human resources. Families need to save, and to so, they must refrain from having many children. Africa should resist the temptation to waste, as rich countries do, and denounce it. Africa needs to become more independent of these countries, but structural adjustment plans, growing debt, and rapid population growth limit national independence. Food aid is a means for developed countries to dominate developing countries. Modernization through foreign aid has had some positive effects on developing countries (e.g., improved hygiene, mortality reduction), but these also sparked rapid population growth. Rwandan society is no longer traditional, but it is also not yet modern. A change in mentality to fewer births, better quality of life for living infants, better education, and less burden for women must occur

  9. Experiments on the fluid dynamics and thermodynamics of rod bundles to verify and support the design of SNR-300 fuel elements - status and open problems

    International Nuclear Information System (INIS)

    Moeller, R.; Weinberg, D.; Trippe, G.; Tschoeke, H.

    1978-01-01

    The reliable design of reactor core elements calls for precise knowledge of the 3D-temperature fields of the different components; this primarily applies to the fuel element cladding tubes, these being the first safety barrier. This paper describes and discusses where and how the 3D-temperature fields so far determined exclusively with the help of global thermohydraulic computer codes (SUBCHANNEL-Codes) have to be determined more accurately by local investigations. The basis of these investigations is the measurement of local velocities and temperatures in 19-rod bundle models of the SNR-300 fuel element performed at the Kernforschungszentrum Karlsruhe (KfK). Some important results of the extensive experimental investigations are reported and compared with global and local recalculations. Open problems are pointed out. The influence of the uncertainties in the thermohydraulic design with respect to the strength analysis are discussed. The most significant results and conclusions are: (1) The peripheral bundle region is the critical zone, which has to be investigated with priority. Here the maximal azimuthal temperature differences of the claddings are ten times higher than those in the central bundle region. (2) The present deviations between thermal experiments and global as well as local calculations are much too high. Within the parameters investigated a careful code adaptation to the experiments is of high priority. (3) The knowledge gaps concerning liquid metal heat transfer in irregular geometries have to be closed. (4) The hot-channel analysis has to be checked with respect to the latest more detailed knowledge of thermohydraulics. (author)

  10. Creativity for Problem Solvers

    DEFF Research Database (Denmark)

    Vidal, Rene Victor Valqui

    2009-01-01

    This paper presents some modern and interdisciplinary concepts about creativity and creative processes specially related to problem solving. Central publications related to the theme are briefly reviewed. Creative tools and approaches suitable to support problem solving are also presented. Finally......, the paper outlines the author’s experiences using creative tools and approaches to: Facilitation of problem solving processes, strategy development in organisations, design of optimisation systems for large scale and complex logistic systems, and creative design of software optimisation for complex non...

  11. Design solutions to interface flow problems. A review of groundwater flow and radionuclide migration along sealed radioactive waste repository tunnels. Final report

    International Nuclear Information System (INIS)

    1986-02-01

    All published proposals for the deep level burial of radioactive waste recognise that the access shafts, tunnels and boreholes must be sealed, and that the sealing of these openings plays an integral role in the overall isolation of the waste. Previous studies have identified the interface between the host ground formation and the various sealing materials as potential defects in the overall quality of the waste isolation. The significance of groundwater flow at and near the interface has been assessed for representative conditions in generic repository materials. A range of design options to minimise the significance of flow in the interface zone have been proposed, and the most practical of these options have been selected for quantitative analysis. It has been found that isolated high impermeability collars are of limited value unless a highly effective method of minimising ground disturbance during excavation can be developed. It has also been found that control of radionuclide migration by sorptive processes provides an attractive option. The effect of various geometrical arrangements of sorptive materials has been investigated. Consideration has also been given to the particular conditions in the near field, to the behaviour of weak plastic clay host formations and to the mechanical interaction between the backfill material and the host formation. (author)

  12. Rates of induced abortion in Denmark according to age, previous births and previous abortions

    Directory of Open Access Journals (Sweden)

    Marie-Louise H. Hansen

    2009-11-01

    Full Text Available Background: Whereas the effects of various socio-demographic determinants on a woman's risk of having an abortion are relatively well-documented, less attention has been given to the effect of previous abortions and births. Objective: To study the effect of previous abortions and births on Danish women's risk of an abortion, in addition to a number of demographic and personal characteristics. Data and methods: From the Fertility of Women and Couples Dataset we obtained data on the number of live births and induced abortions by year (1981-2001, age (16-39, county of residence and marital status. Logistic regression analysis was used to estimate the influence of the explanatory variables on the probability of having an abortion in a relevant year. Main findings and conclusion: A woman's risk of having an abortion increases with the number of previous births and previous abortions. Some interactions were was found in the way a woman's risk of abortion varies with calendar year, age and parity. The risk of an abortion for women with no children decreases while the risk of an abortion for women with children increases over time. Furthermore, the risk of an abortion decreases with age, but relatively more so for women with children compared to childless women. Trends for teenagers are discussed in a separate section.

  13. The bone-anchored hearing aid: a solution for previously unresolved otologic problems.

    NARCIS (Netherlands)

    Snik, A.F.M.; Mylanus, E.A.M.; Cremers, C.W.R.J.

    2001-01-01

    A major challenge for otologists treating middle ear infection is to obtain a dry ear and optimal hearing. If the patient needs amplification and uses an air conduction hearing aid, the ear mold, occluding the ear canal, may provoke or aggravate the infection in the middle ear and thus cause

  14. Congruency sequence effects are driven by previous-trial congruency, not previous-trial response conflict

    OpenAIRE

    Weissman, Daniel H.; Carp, Joshua

    2013-01-01

    Congruency effects in distracter interference tasks are often smaller after incongruent trials than after congruent trials. However, the sources of such congruency sequence effects (CSEs) are controversial. The conflict monitoring model of cognitive control links CSEs to the detection and resolution of response conflict. In contrast, competing theories attribute CSEs to attentional or affective processes that vary with previous-trial congruency (incongruent vs. congruent). The present study s...

  15. Speech Problems

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Speech Problems KidsHealth / For Teens / Speech Problems What's in ... a person's ability to speak clearly. Some Common Speech and Language Disorders Stuttering is a problem that ...

  16. Hemiequilibrium problems

    Directory of Open Access Journals (Sweden)

    Muhammad Aslam Noor

    2004-01-01

    Full Text Available We consider a new class of equilibrium problems, known as hemiequilibrium problems. Using the auxiliary principle technique, we suggest and analyze a class of iterative algorithms for solving hemiequilibrium problems, the convergence of which requires either pseudomonotonicity or partially relaxed strong monotonicity. As a special case, we obtain a new method for hemivariational inequalities. Since hemiequilibrium problems include hemivariational inequalities and equilibrium problems as special cases, the results proved in this paper still hold for these problems.

  17. The Problem Revisited

    DEFF Research Database (Denmark)

    Ovesen, Nis

    2015-01-01

    Problem-based learning (PBL) is becoming increasingly popular in design educations, but how is it taught and practiced? This paper presents a case study of a three-day workshop that has the purpose of introducing PBL to design students. A theoretical background on PBL and problems in design is es...... is established and is backing up the case study. The study shows that design engineering and architectural students without experience in PBL in general finds the approach to be beneficial when working on a design challenge in a student team....

  18. Evaluating the Effectiveness of an Integrated Cognitive-Behavioural Intervention (CBI) Model for Male Problem Gamblers in Hong Kong: A Matched-Pair Comparison Design.

    Science.gov (United States)

    Zhuang, Xiao Yu; Wong, Daniel Fu Keung; Ng, Ting Kin; Jackson, Alun C; Dowling, Nicki A; Lo, Herman Hay-Ming

    2018-01-22

    Very few clinical cognitive-behavioural intervention (CBI) studies were conducted with the Chinese gamblers. There is a lack of attention paid to intervening in negative emotions that may also adversely affect PGs in current CBI treatment modality. This study is the first attempt to systematically and rigorously evaluate both the short-term and longer-term effects of a culturally-attuned CBI group treatment with an emotion regulation component for a group of Chinese PGs in Hong Kong. A quasi-experimental matched-pairs design was adopted and 84 participants were allocated to the CBI (N = 42) and social activity groups (N = 42). There are 3 assessment points in the study: baseline at recruitment, post-intervention at the end of CBI and social activity groups, and at 6-month follow-up. When compared to the social activity group and after controlling for general group effects, there were significantly greater decreases in the severity of gambling, gambling-related cognitions (i.e. interpretive bias), negative psychological states (i.e. stress) and money spent on gambling in the past month in the CBI group between pre- and post-intervention and between pre-intervention and 6-month follow-up. Results also indicated that both reduction in gambling-related cognitions and negative psychological states could mediate the treatment effect of the CBI on the reduction of problematic gambling behaviours. The culturally attuned integrated CBI group treatment with an emotional regulation component appeared to be effective in treating Chinese problem gamblers in Hong Kong and the effects could be sustained at 6-month follow-up.

  19. Multispecies Coevolution Particle Swarm Optimization Based on Previous Search History

    Directory of Open Access Journals (Sweden)

    Danping Wang

    2017-01-01

    Full Text Available A hybrid coevolution particle swarm optimization algorithm with dynamic multispecies strategy based on K-means clustering and nonrevisit strategy based on Binary Space Partitioning fitness tree (called MCPSO-PSH is proposed. Previous search history memorized into the Binary Space Partitioning fitness tree can effectively restrain the individuals’ revisit phenomenon. The whole population is partitioned into several subspecies and cooperative coevolution is realized by an information communication mechanism between subspecies, which can enhance the global search ability of particles and avoid premature convergence to local optimum. To demonstrate the power of the method, comparisons between the proposed algorithm and state-of-the-art algorithms are grouped into two categories: 10 basic benchmark functions (10-dimensional and 30-dimensional, 10 CEC2005 benchmark functions (30-dimensional, and a real-world problem (multilevel image segmentation problems. Experimental results show that MCPSO-PSH displays a competitive performance compared to the other swarm-based or evolutionary algorithms in terms of solution accuracy and statistical tests.

  20. Teaching sustainable design

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, P.; Haggard, K.; Knuckles, A.; Le Noble, J. [California Polytechnic State Univ., San Luis Obispo, CA (United States)

    1995-11-01

    Sustainable design is inclusive, holistic and integrative. It require humility and guts, caring and a certain degree of stubbornness. It helps to do it cooperatively in a group. Human interest in sustainability has gained a great deal of impetus over the last several years as the problems of the late 20th and the early 21st century have become clearer. Design for sustainability broadens and integrates many previously separate design concerns to create a unified approach that is both compelling and ripe with new possibilities. Ecosystem regeneration, ecological land use planning, biometric design, regional environmental and economic viability, natural landscape maintenance, resource optimization, integrated infrastructure system, neotraditional and pedestrian oriented urban design, passive solar architecture, appropriate technology, renewable building materials, healthy buildings, and the aesthetics of place; are a few of these design concerns that, when welded together, can create sustainability.

  1. The Technology Fair: A Project-Based Learning Approach for Enhancing Problem Solving Skills and Interest in Design and Technology Education

    Science.gov (United States)

    Mettas, Alexandros C.; Constantinou, Constantinos C.

    2008-01-01

    This paper presents an innovative way in which university education can help pre-service teachers become better problem-solvers. The central idea is to use the "Technology Fair" as a means for promoting pre-service teachers pedagogical content knowledge about technological problem solving skills. This innovation is supported with results from a…

  2. HEART TRANSPLANTATION IN PATIENTS WITH PREVIOUS OPEN HEART SURGERY

    Directory of Open Access Journals (Sweden)

    R. Sh. Saitgareev

    2016-01-01

    cited in the review may have important clinical applications, because they outline the range of problems and possible solutions in the performance of the HTx in recipients previously operated on open heart. This knowledge can facilitate the decision making process with regard to the opportunities and risks of the implementation of HTx. Given the uniqueness of each of the recipient and the donor, it is required to make a personalized approach to the question of the possible risks and to the preventive measures to reduce those risks in any given clinical situation. 

  3. Problem gambling.

    Science.gov (United States)

    Thomas, Shane

    2014-06-01

    Problem gambling is an increasingly common problem in Australia. General practitioners (GPs) have an important role in ensuring that problem gambling is detected and treated. We review the clinical issues associated with the detection and treatment of problem gambling. At any one time 1% of the adult Australian population satisfy the clinical criteria for problem gambling; a further 4% are at a significant risk. Problem gambling frequently presents with other serious mental health conditions. There are several guidelines from the National Health and Medical Research Council and Australian Medical Association that recommend GP involvement in screening for problem gambling. Simple one-item tools are available for that purpose. GP screening and referral for problem gambling addresses the currently very low rates of treatment. Effective and durable psychological treatments are available for the treatment of problem gambling including cognitive behaviour therapy and motivational interviewing.

  4. Problems in baryon spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Capstick, S. [Florida State Univ., Tallahassee, FL (United States)

    1994-04-01

    Current issues and problems in the physics of ground- and excited-state baryons are considered, and are classified into those which should be resolved by CEBAF in its present form, and those which may require CEBAF to undergo an energy upgrade to 8 GeV or more. Recent theoretical developments designed to address these problems are outlined.

  5. Childbirth Problems

    Science.gov (United States)

    ... the mother, baby, or both. Possible complications include Preterm (premature) labor, when labor starts before 37 completed weeks of pregnancy Problems with the umbilical cord Problems with the position of the baby, such as breech, in which ...

  6. Ankle Problems

    Science.gov (United States)

    ... Read MoreDepression in Children and TeensRead MoreBMI Calculator Ankle ProblemsFollow this chart for more information about problems that can cause ankle pain. Our trusted Symptom Checker is written and ...

  7. Walking Problems

    Science.gov (United States)

    ... your legs or feet Movement disorders such as Parkinson's disease Diseases such as arthritis or multiple sclerosis Vision or balance problems Treatment of walking problems depends on the cause. Physical therapy, surgery, or mobility aids may help.

  8. Motivational activities based on previous knowledge of students

    Science.gov (United States)

    García, J. A.; Gómez-Robledo, L.; Huertas, R.; Perales, F. J.

    2014-07-01

    Academic results depend strongly on the individual circumstances of students: background, motivation and aptitude. We think that academic activities conducted to increase motivation must be tuned to the special situation of the students. Main goal of this work is analyze the students in the first year of the Degree in Optics and Optometry in the University of Granada and the suitability of an activity designed for those students. Initial data were obtained from a survey inquiring about the reasons to choose this degree, their knowledge of it, and previous academic backgrounds. Results show that: 1) the group is quite heterogeneous, since students have very different background. 2) Reasons to choose the Degree in Optics and Optometry are also very different, and in many cases were selected as a second option. 3) Knowledge and motivations about the Degree are in general quite low. Trying to increase the motivation of the students we designed an academic activity in which we show different topics studied in the Degree. Results show that students that have been involved in this activity are the most motivated and most satisfied with their election of the degree.

  9. Low Achieving Eighth Graders Learn to Crack Word Problems: A Design Research Project for Aligning a Strategic Scaffolding Tool to Students' Mental Processes

    Science.gov (United States)

    Prediger, Susanne; Krägeloh, Nadine

    2015-01-01

    Topic-specific didactical design research provides means not only to investigate how to learn but also what to learn, i.e., for specifying learning contents by analyzing students' comprehension processes in detail. This important characteristic of didactical design research is exemplarily shown for students' difficulties in finding symbolic…

  10. Collaborative problem structuring using MARVEL

    NARCIS (Netherlands)

    Veldhuis, G.A.; Scheepstal, P.G.M. van; Rouwette, E.A.J.A.; Logtens, T.W.A.

    2015-01-01

    When faced with wicked and messy problems, practitioners can rely on a variety of problem structuring methods (PSMs). Although previous efforts have been made to combine such methods with simulation, currently, few exist that integrate a simulation capability within problem structuring. Our

  11. Simon on problem solving

    DEFF Research Database (Denmark)

    Foss, Kirsten; Foss, Nicolai Juul

    2006-01-01

    as a general approach to problem solving. We apply these Simonian ideas to organisational issues, specifically new organisational forms. Specifically, Simonian ideas allow us to develop a morphology of new organisational forms and to point to some design problems that characterise these forms.......Two of Herbert Simon's best-known papers are 'The Architecture of Complexity' and 'The Structure of Ill-Structured Problems.' We discuss the neglected links between these two papers, highlighting the role of decomposition in the context of problems on which constraints have been imposed...

  12. Shielding benchmark problems, (2)

    International Nuclear Information System (INIS)

    Tanaka, Shun-ichi; Sasamoto, Nobuo; Oka, Yoshiaki; Shin, Kazuo; Tada, Keiko.

    1980-02-01

    Shielding benchmark problems prepared by Working Group of Assessment of Shielding Experiments in the Research Committee on Shielding Design in the Atomic Energy Society of Japan were compiled by Shielding Laboratory in Japan Atomic Energy Research Institute. Fourteen shielding benchmark problems are presented newly in addition to twenty-one problems proposed already, for evaluating the calculational algorithm and accuracy of computer codes based on discrete ordinates method and Monte Carlo method and for evaluating the nuclear data used in codes. The present benchmark problems are principally for investigating the backscattering and the streaming of neutrons and gamma rays in two- and three-dimensional configurations. (author)

  13. Design and Development of Virtual Reality Simulation for Teaching High-Risk Low-Volume Problem-Prone Office-Based Medical Emergencies

    Science.gov (United States)

    Lemheney, Alexander J.

    2014-01-01

    Physicians' offices are not the usual place where emergencies occur; thus how staff remains prepared and current regarding medical emergencies presents an ongoing challenge for private practitioners. The very nature of low-volume, high-risk, and problem-prone medical emergencies is that they occur with such infrequency it is difficult for staff to…

  14. Challenges in Designing Appropriate Scaffolding to Improve Students' Representational Consistency: The Case of a Gauss's Law Problem

    Science.gov (United States)

    Maries, Alexandru; Lin, Shih-Yin; Singh, Chandralekha

    2017-01-01

    Prior research suggests that introductory physics students have difficulty with graphing and interpreting graphs. Here, we discuss an investigation of student difficulties in translating between mathematical and graphical representations for a problem in electrostatics and the effect of increasing levels of scaffolding on students'…

  15. The efficacy of a standardized questionnaire in facilitating personalized communication about problems encountered in cancer genetic counseling: design of a randomized controlled trial.

    Science.gov (United States)

    Eijzenga, Willem; Aaronson, Neil K; Kluijt, Irma; Sidharta, Grace N; Hahn, Daniela Ee; Ausems, Margreet Gem; Bleiker, Eveline Ma

    2014-01-15

    Individuals with a personal or family history of cancer, can opt for genetic counseling and DNA-testing. Approximately 25% of these individuals experience clinically relevant levels of psychosocial distress, depression and/or anxiety after counseling. These problems are frequently left undetected by genetic counselors. The aim of this study is to evaluate the efficacy of a cancer genetics-specific screening questionnaire for psychosocial problems, the 'Psychosocial Aspects of Hereditary Cancer (PAHC) questionnaire' together with the Distress Thermometer, in: (1) facilitating personalized counselor-counselee communication; (2) increasing counselors' awareness of their counselees' psychosocial problems; and (3) facilitating the management of psychosocial problems during and after genetic counseling. This multicenter, randomized controlled trial will include 264 individuals undergoing cancer genetic counseling in two family cancer clinics in the Netherlands. Participants will be randomized to either: (1) an intervention group that completes the PAHC questionnaire, the results of which are made available to the genetic counselor prior to the counseling session; or (2) a control group that completes the PAHC questionnaire, but without feedback being given to the genetic counselor. The genetic counseling sessions will be audiotaped for content analysis. Additionally, study participants will be asked to complete questionnaires at baseline, three weeks after the initial counseling session, and four months after a telephone follow-up counseling session. The genetic counselors will be asked to complete questionnaires at the start of and at completion of the study, as well as a checklist directly after each counseling session. The questionnaires/checklists of the study include items on communication during genetic counseling, counselor awareness of their clients' psychosocial problems, the (perceived) need for professional psychosocial support, cancer worries, general

  16. Prompting Designers to Design

    DEFF Research Database (Denmark)

    Ahmed, Saeema

    2007-01-01

    Recent research suggest that engineering designers need assistance to understand what information is relevant for their particular design problem. They require guidance in formulating their queries and also to understand what information is relevant for them. This paper presents an approach...... to prompt designers with their design queries. A method that automatically extracts relationships between concepts is described, along with some examples. The method can be implemented as part of knowledge management system and the relationships are extracted form documents that are indexed within...... literature related to: 1) an understanding of how engineering designers search for information and 2) an understanding of the nature of experience in engineering design. Hence these are reviewed in the following sections....

  17. Prompting Designers to Design

    DEFF Research Database (Denmark)

    Ahmed, Saeema

    2006-01-01

    Recent research suggest that engineering designers need assistance to understand what information is relevant for their particular design problem. They require guidance in formulating their queries and also to understand what information is relevant for them. This paper presents an approach...... to prompt designers with their design queries. A method that automatically extracts relationships between concepts is described, along with some examples. The method can be implemented as part of knowledge management system and the relationships are extracted form documents that are indexed within...... literature related to: 1) an understanding of how engineering designers search for information and 2) an understanding of the nature of experience in engineering design. Hence these are reviewed in the following sections...

  18. Targeting Alzheimer's disease by investigating previously unexplored chemical space surrounding the cholinesterase inhibitor donepezil

    CSIR Research Space (South Africa)

    Van Greunen, DG

    2017-02-01

    Full Text Available A series of twenty seven acetylcholinesterase inhibitors, as potential agents for the treatment of Alzheimer's disease, were designed and synthesised based upon previously unexplored chemical space surrounding the molecular skeleton of the drug...

  19. Participation of end users in the design of assistive technology for people with mild to severe cognitive problems; The European Rosetta project

    NARCIS (Netherlands)

    Meiland, F.J.M.; Hattink, B.J.J.; Overmars-Marx, T.; Boer, M.E. de; Jedlitschka, A.; Ebben, P.W.G.; Stalpers-Croeze, I.I.N.W.; Flick, S.; Leeuw, J. van der; Karkowski, I.P.; Dröes, R.M.

    2014-01-01

    Background: In the European Rosetta project three separate, previously developed, ICT systems were improved and integrated to create one modular system that helps community-dwelling people with mild cognitive impairment and dementia in different stages of the disease. The system aims to support them

  20. The Design of Holistic Innovation Policy

    DEFF Research Database (Denmark)

    Borrás, Susana; Edquist, Charles

    looks into a series of issues related to the design of holistic innovation policy. With this purpose in mind, this chapter summarizes previous chapters’ identification of the problems, bottlenecks and deficiencies that can afflict innovation systems. Taken together, they provide the theoretical...... foundations for the design of holistic innovation policy, which includes not only framing the problems in the innovation system, but also considerations about policy instruments for the tasks at hand, as well as the problems generated by policy itself (unintended consequences of inefficient of incomplete...

  1. Sociale problemer

    DEFF Research Database (Denmark)

    Christensen, Anders Bøggild; Rasmussen, Tove; Bundesen, Peter Verner

    række fagfolk på tværs af det danske socialfaglige felt fokus på sociale problemer. Det diskuteres, hvad vi overhovedet forstår ved sociale problemer, hvordan de opstår, hvilke konsekvenser de har, og ikke mindst hvordan man som fagprofessionel håndterer sociale problemer i det daglige arbejde. Bogen er...... skrevet som lærebog til professionsuddannelser, hvor sociale problemer udgør en dimension, bl.a. socialrådgiver-, pædagog- og sygeplejerskeuddannelserne....

  2. Mechatronic control engineering and electro-mechanical system design - two mechatronic curricula at Aalborg University based on problem oriented and project based learning

    DEFF Research Database (Denmark)

    Pedersen, Henrik C.; Andersen, Torben Ole; Rasmussen, Peter Omand

    2009-01-01

    using a subsystem based approach. The challenges related to teaching and learning mechatronics are addressed, discussing how mechatronics is typically taught around the world also illustrating the trends and applications of mechatronic engineering and research. This is followed by an outline......, it is addressed how a mechatronic education is structured so courses and projects are aligned, to utilize the full benefits of the Problem Oriented Project Based Learning (POPBL) system practiced at AalborgUniversity (AAU). This is followed by a presentation of the two complementary educations in Mechatronicsat...... AAU, describing course outline and project content of the different semesters, where also the thoughts behind the organization of the curricula are addressed. Finally the paper summarizes with an overview of the experiences gained at AAU with teaching mechatronics in a Problem Oriented and Project...

  3. Integrated Cognitive-neuroscience Architectures for Understanding Sensemaking (ICArUS): A Computational Basis for ICArUS Challenge Problem Design

    Science.gov (United States)

    2014-11-01

    models at the biological and psychological levels) first requires a computational theory of sensemaking at the functional level, in the Marr (1982...from the scope of the ICArUS program. Like RASKRs discussed above, ICArUS models are not being developed to solve problems of vision or language. And...because neural models will not have those capabilities, human subjects should not exploit their own capabilities for vision and language if

  4. Exact and approximation algorithms for DNA tag set design.

    Science.gov (United States)

    Măndoiu, Ion I; Trincă, Dragoş

    2006-04-01

    In this paper, we propose new solution methods for designing tag sets for use in universal DNA arrays. First, we give integer linear programming formulations for two previous formalizations of the tag set design problem. We show that these formulations can be solved to optimality for problem instances of moderate size by using general purpose optimization packages and also give more scalable algorithms based on an approximation scheme for packing linear programs. Second, we note the benefits of periodic tags and establish an interesting connection between the tag design problem and the problem of packing the maximum number of vertex-disjoint directed cycles in a given graph. We show that combining a simple greedy cycle packing algorithm with a previously proposed alphabetic tree search strategy yields an increase of over 40% in the number of tags compared to previous methods.

  5. Sacrococcygeal pilonidal disease: analysis of previously proposed risk factors

    Directory of Open Access Journals (Sweden)

    Ali Harlak

    2010-01-01

    Full Text Available PURPOSE: Sacrococcygeal pilonidal disease is a source of one of the most common surgical problems among young adults. While male gender, obesity, occupations requiring sitting, deep natal clefts, excessive body hair, poor body hygiene and excessive sweating are described as the main risk factors for this disease, most of these need to be verified with a clinical trial. The present study aimed to evaluate the value and effect of these factors on pilonidal disease. METHOD: Previously proposed main risk factors were evaluated in a prospective case control study that included 587 patients with pilonidal disease and 2,780 healthy control patients. RESULTS: Stiffness of body hair, number of baths and time spent seated per day were the three most predictive risk factors. Adjusted odds ratios were 9.23, 6.33 and 4.03, respectively (p<0.001. With an adjusted odds ratio of 1.3 (p<.001, body mass index was another risk factor. Family history was not statistically different between the groups and there was no specific occupation associated with the disease. CONCLUSIONS: Hairy people who sit down for more than six hours a day and those who take a bath two or less times per week are at a 219-fold increased risk for sacrococcygeal pilonidal disease than those without these risk factors. For people with a great deal of hair, there is a greater need for them to clean their intergluteal sulcus. People who engage in work that requires sitting in a seat for long periods of time should choose more comfortable seats and should also try to stand whenever possible.

  6. Foot Problems

    Science.gov (United States)

    ... can also cause foot problems. The Most Common Types of Foot Problems In older adults, the foot complaints encountered ... people include: Arch pain . From fallen arches (flat feet), or abnormally high arches. Tarsal tunnel syndrome . A type of pinched nerve disorder. Achilles tendonitis . Inflammation of ...

  7. Problem Periods

    Science.gov (United States)

    ... during your menstrual cycle Premenstrual syndrome (PMS) Problem periods Getting enough sleep Looking and feeling your best Fighting germs Your sexuality What are STDs and STIs? Seeing the doctor Quizzes Links to more information on girls' bodies girlshealth glossary girlshealth.gov home http://www.girlshealth.gov/ Home ... Problem periods It’s common to have ...

  8. Cooperative design

    DEFF Research Database (Denmark)

    Schmidt, Kjeld

    1998-01-01

    if concurrent engineering is to succeed. On the basis of ethnographic studies of cooperative design, the paper attempts to characterize cooperative work in the domain of design and to outline a set of crucial research problems to be addressed if CSCW is to help engineers and de-signers meet the challenges...

  9. 22 CFR 40.91 - Certain aliens previously removed.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Certain aliens previously removed. 40.91... IMMIGRANTS UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Aliens Previously Removed § 40.91 Certain aliens previously removed. (a) 5-year bar. An alien who has been found inadmissible, whether as a result...

  10. Determining root correspondence between previously and newly detected objects

    Science.gov (United States)

    Paglieroni, David W.; Beer, N Reginald

    2014-06-17

    A system that applies attribute and topology based change detection to networks of objects that were detected on previous scans of a structure, roadway, or area of interest. The attributes capture properties or characteristics of the previously detected objects, such as location, time of detection, size, elongation, orientation, etc. The topology of the network of previously detected objects is maintained in a constellation database that stores attributes of previously detected objects and implicitly captures the geometrical structure of the network. A change detection system detects change by comparing the attributes and topology of new objects detected on the latest scan to the constellation database of previously detected objects.

  11. The measurement of the earth's radiation budget as a problem in information theory - A tool for the rational design of earth observing systems

    Science.gov (United States)

    Barkstrom, B. R.

    1983-01-01

    The measurement of the earth's radiation budget has been chosen to illustrate the technique of objective system design. The measurement process is an approximately linear transformation of the original field of radiant exitances, so that linear statistical techniques may be employed. The combination of variability, measurement strategy, and error propagation is presently made with the help of information theory, as suggested by Kondratyev et al. (1975) and Peckham (1974). Covariance matrices furnish the quantitative statement of field variability.

  12. Breathing Problems

    Science.gov (United States)

    ... getting enough air. Sometimes you can have mild breathing problems because of a stuffy nose or intense ... panic attacks Allergies If you often have trouble breathing, it is important to find out the cause.

  13. Sleep Problems

    Science.gov (United States)

    ... For Consumers Consumer Information by Audience For Women Sleep Problems Share Tweet Linkedin Pin it More sharing ... 101 KB) En Español Medicines to Help You Sleep Tips for Better Sleep Basic Facts about Sleep ...

  14. Tongue problems

    Science.gov (United States)

    ... Tongue pain may also occur with: Diabetic neuropathy Leukoplakia Mouth ulcers Oral cancer After menopause, some women have ... problem. Medicine may be prescribed for mouth ulcers, leukoplakia, oral cancer, and other mouth sores. Anti-inflammatory medicines ...

  15. Kidney Problems

    Science.gov (United States)

    ... High Blood Pressure Nutrition Join our e-newsletter! Aging & Health A to Z Kidney Problems Basic Facts & ... specialize in the care of people with kidney (renal) diseases are called nephrologists . What are Kidney Diseases? ...

  16. Foot Problems

    Science.gov (United States)

    ... Start OverDiagnosisThese thickened areas are likely to be CORNS. If they appear to have small granules in ... these problems. Self CareUse an over-the-counter corn or wart remover. Remove the dead skin after ...

  17. Popular Problems

    DEFF Research Database (Denmark)

    Skovhus, Randi Boelskifte; Thomsen, Rie

    2017-01-01

    to be’ (WPR) approach. Forty-nine empirical studies on Danish youth career guidance were included in the study. An analysis of the issues in focus resulted in nine problem categories. One of these, ‘targeting’, is analysed using the WPR approach. Finally, the article concludes that the WPR approach...... provides a constructive basis for a critical analysis and discussion of the collective empirical knowledge production on career guidance, stimulating awareness of problems and potential solutions among the career guidance community....

  18. Knapsack problems

    CERN Document Server

    Kellerer, Hans; Pisinger, David

    2004-01-01

    Thirteen years have passed since the seminal book on knapsack problems by Martello and Toth appeared. On this occasion a former colleague exclaimed back in 1990: "How can you write 250 pages on the knapsack problem?" Indeed, the definition of the knapsack problem is easily understood even by a non-expert who will not suspect the presence of challenging research topics in this area at the first glance. However, in the last decade a large number of research publications contributed new results for the knapsack problem in all areas of interest such as exact algorithms, heuristics and approximation schemes. Moreover, the extension of the knapsack problem to higher dimensions both in the number of constraints and in the num­ ber of knapsacks, as well as the modification of the problem structure concerning the available item set and the objective function, leads to a number of interesting variations of practical relevance which were the subject of intensive research during the last few years. Hence, two years ago ...

  19. Previous early antenatal service utilization improves timely booking: cross-sectional study at university of Gondar hospital, northwest Ethiopia.

    Science.gov (United States)

    Belayneh, Tadesse; Adefris, Mulat; Andargie, Gashaw

    2014-01-01

    Early booking of antenatal care (ANC) is regarded as a cornerstone of maternal and neonatal health care. However, existing evidence from developing countries indicate that lots of pregnant woman begin ANC booking lately. Objective. It was aimed to assess timing of ANC booking and associated factors among pregnant women attending ANC clinic at University of Gondar Hospital, 2013. An institution based cross-sectional study design was used to collect data with a face-to-face interview technique. Bivariate and multivariate analysis was used to identify associated factors for early ANC visit using SPSS version 20. From total women (N = 369) interviewed, 47.4% were timely booked. Mothers with younger age (AOR = 3.83, 95% CI: 1.89, 10.53), formal education (AOR = 1.06, 95% CI: 1.03, -7.61), previous early ANC visit (AOR = 2.39, 95% CI: 2.23, 9.86), and perceived ANC visit per pregnancy of four and greater were significantly associated with early ANC visit. Although late booking is a problem in this study, previous early utilization of ANC visit favors current timely booking. This indicates that the importance of early booking was appropriately addressed from previous visits. Counseling of timely booking during ANC visit should be strengthened. Moreover, empowering through education is also recommended.

  20. Design '82

    International Nuclear Information System (INIS)

    1982-01-01

    The papers in the symposium cover many aspects of the economy and effectiveness of chemical engineering design in industrial plants. Among the topics dealt with are the special problems associated with nuclear reprocessing plants. (U.K.)

  1. Seven Experiment Designs Addressing Problems of Safety and Capacity on Two-Lane Rural Highways : Volume 6. Experimental Design for Comparative Evaluation of Warning-Advisory and Regulatory Traffic Control Devices

    Science.gov (United States)

    1978-05-01

    The overuse of regulatory type signing on highways has been found to cause motorists to ignore all signing. In this experimental design, advisory-warning signs, regulatory signs and a combination of the two types will be tested in four experiments. T...

  2. Seven Experiment Designs Addressing Problems of Safety and Capacity on Two-Lane Rural Highways : Volume 8. Experimental Design and Evaluate Remedial Aids for Intersections with Inadequate Sight Distance

    Science.gov (United States)

    1978-05-01

    The experiment is planned for low-volume rural intersections on or near the Maine Facility. A number of remedial aids, both active and dynamic, are tested. The devices are designed either to focus the motorist's attention on existing conditions or to...

  3. Spring Recipes A Problem-solution Approach

    CERN Document Server

    Long, Josh; Mak, Gary

    2010-01-01

    With over 3 Million users/developers, Spring Framework is the leading "out of the box" Java framework. Spring addresses and offers simple solutions for most aspects of your Java/Java EE application development, and guides you to use industry best practices to design and implement your applications. The release of Spring Framework 3 has ushered in many improvements and new features. Spring Recipes: A Problem-Solution Approach, Second Edition continues upon the bestselling success of the previous edition but focuses on the latest Spring 3 features for building enterprise Java applications.

  4. Solving "Smart City" Transport Problems by Designing Carpooling Gamification Schemes with Multi-Agent Systems: The Case of the So-Called "Mordor of Warsaw".

    Science.gov (United States)

    Olszewski, Robert; Pałka, Piotr; Turek, Agnieszka

    2018-01-06

    To reduce energy consumption and improve residents' quality of life, "smart cities" should use not only modern technologies, but also the social innovations of the "Internet of Things" (IoT) era. This article attempts to solve transport problems in a smart city's office district by utilizing gamification that incentivizes the carpooling system. The goal of the devised system is to significantly reduce the number of cars, and, consequently, to alleviate traffic jams, as well as to curb pollution and energy consumption. A representative sample of the statistical population of people working in one of the biggest office hubs in Poland (the so-called "Mordor of Warsaw") was surveyed. The collected data were processed using spatial data mining methods, and the results were a set of parameters for the multi-agent system. This approach made it possible to run a series of simulations on a set of 100,000 agents and to select an effective gamification methodology that supports the carpooling process. The implementation of the proposed solutions (a "serious game" variation of urban games) would help to reduce the number of cars by several dozen percent, significantly reduce energy consumption, eliminate traffic jams, and increase the activity of the smart city residents.

  5. Development of two-dimensional lattice Boltzmann code DG2LBM for computational fluid dynamic problems in nuclear reactor safety component design

    International Nuclear Information System (INIS)

    Park, Jong Woon

    2012-01-01

    A 2-dimensional computational fluid dynamic analysis program DG2LBM by using Lattice Boltzmann Equation (LBE) with momentum exchange boundary conditions is developed and it is applied to a feasibility study of nuclear reactor safety component such as a reactor building floor weir (RBFW), a simple as well as an effective option to sediment particulate materials generated after loss of coolant accident of a nuclear power plant and. The program is benchmarked against a standard problem of a flow past a cylinder at relatively low Reynolds numbers, the RBFW is simulated for diverse parametric conditions such as height, inclination angle, number of weirs (1 or 2) and the distance between two weirs. The weir performance is measured by the area of quiescent and/or downward reverse flow region where particles have more chance to sediment. It is found a wake causing reverse downward flow behind the weir mainly contributes to generating the quiescent flow region. And the most effective option in terms of particle sedimentation performance is found to be relatively tall double weirs separated by 2 weir heights. (orig.)

  6. Hybrid environment for software sensors design applied to the petrochemical industry problems; Ambiente hibrido para a concepcao de sensores de software aplicados aos problemas da industria petroquimica

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Bruno X.; Ramalho, Leonardo S.G.; Rodrigues, Igor O.; Martins, Daniel L.; Doria Neto, Adriao D.; Melo, Jorge D.; Oliveira, Luiz A.H.G.G. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2008-07-01

    This article will show a hybrid environment for the conception of software sensors in Foundation Fieldbus (FF) industrial network. These sensors are focused on the measurement and control problems in the petroleum industry, more specifically in oil and gas refining, contributing for the efficiency increase and operation costs decrease of a refining process. The software sensors are based on intelligent algorithms, as neural networks, fuzzy logic and genetic algorithms. These algorithms need input data, in this case the historical variables data associated to industrial petrochemical plant. One option allowed by the environment is the data acquisition from a simulated process by the FF network. Then, the environment presents a hybrid feature, since it is composed by a real (the industrial network) and a simulated (the process) part, with the use of real control and measurements signals. The environment is flexible, allowing typical dynamics of industrial process reproduction without necessity of the physical network amendment and enabling the creation of several situations from a real industrial environment. (author)

  7. 2 CFR 1.215 - Relationship to previous issuances.

    Science.gov (United States)

    2010-01-01

    ... 2 Grants and Agreements 1 2010-01-01 2010-01-01 false Relationship to previous issuances. 1.215 Section 1.215 Grants and Agreements ABOUT TITLE 2 OF THE CODE OF FEDERAL REGULATIONS AND SUBTITLE A Introduction toSubtitle A § 1.215 Relationship to previous issuances. Although some of the guidance was...

  8. 2 CFR 230.45 - Relationship to previous issuance.

    Science.gov (United States)

    2010-01-01

    ... 2 Grants and Agreements 1 2010-01-01 2010-01-01 false Relationship to previous issuance. 230.45 Section 230.45 Grants and Agreements OFFICE OF MANAGEMENT AND BUDGET CIRCULARS AND GUIDANCE Reserved COST PRINCIPLES FOR NON-PROFIT ORGANIZATIONS (OMB CIRCULAR A-122) § 230.45 Relationship to previous issuance. (a...

  9. Research Note Effects of previous cultivation on regeneration of ...

    African Journals Online (AJOL)

    Research Note Effects of previous cultivation on regeneration of Julbernadia globiflora and Brachystegia spiciformis in grazing areas of Mupfurudzi ... Plant attributes for Julbernadia globiflora and Brachystegia spiciformis were measured in previously cultivated and uncultivated sites making up rangelands of the scheme.

  10. 49 CFR 173.23 - Previously authorized packaging.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Previously authorized packaging. 173.23 Section... REQUIREMENTS FOR SHIPMENTS AND PACKAGINGS Preparation of Hazardous Materials for Transportation § 173.23 Previously authorized packaging. (a) When the regulations specify a packaging with a specification marking...

  11. 75 FR 76056 - FEDERAL REGISTER CITATION OF PREVIOUS ANNOUNCEMENT:

    Science.gov (United States)

    2010-12-07

    ... SECURITIES AND EXCHANGE COMMISSION Sunshine Act Meeting FEDERAL REGISTER CITATION OF PREVIOUS ANNOUNCEMENT: STATUS: Closed meeting. PLACE: 100 F Street, NE., Washington, DC. DATE AND TIME OF PREVIOUSLY ANNOUNCED MEETING: Thursday, December 9, 2010 at 2 p.m. CHANGE IN THE MEETING: Time change. The closed...

  12. Triple outlet right ventricle: a previously unknown cardiac malformation.

    Science.gov (United States)

    Tingo, Jennifer E; Carroll, Sheila J; Crystal, Matthew A

    2015-03-01

    We present the case of an infant with three distinct outflow tracts from the right ventricle. Three outlets from the heart have been previously named the "Tritruncal Heart". We review the two previously reported cases of tritruncal hearts and describe the anatomy, diagnosis, surgical management, and outcome of our case. Embryologic implications are also discussed.

  13. Peculiarities of mental and behavioral disorders due to use of designer drugs among young population and problems of early diagnostics (literature review

    Directory of Open Access Journals (Sweden)

    Spirina I.D.

    2017-06-01

    Full Text Available The analysis of the data of the domestic and foreign literature regarding the dynamics of narcotization among children and adolescents is carried out. It has been established that at present the growth rates of the use of psychoactive substances by minors far outstrip those of the adult population. It is also determined that in most cases "adult" drug addiction is formed in a teenage environment and therefore adolescents are a group of high-risk narcotization. Besides, new types of additions are constantly added: non-opioid analgetics, antidepressants, pharmacy products based on medicinal plants with stimulating or sedative properties, new means of perfumery and household chemicals, volatile organic compounds, etc. In this regard, in the clinical picture of drug intoxication, new variations of affective, psycho-organic and psychosomatic effects and complications are noted. In recent years, synthetic cannabinoids has rapidly gained "popularity" among young people that are successfully promoted by marketers. They are the part of the so-called designer drugs, appearing in the markets in the form of bath salts, flavors, fertilizers for indoor plants and "smoking mixtures" - spices. The publications of domestic and foreign authors give a lot of evidence of the ability of these substances not only to cause a state of intoxication, alienation, relaxation, but also leads to dependence on them with severe consequences for the psyche and all organism as a whole. Thus, the powerful anthropogenic damaging effect of designer drugs demonstrates concrete signals of a threat to health, demography and the economy of the society as a result of their use by the population.

  14. Implant breast reconstruction after salvage mastectomy in previously irradiated patients.

    Science.gov (United States)

    Persichetti, Paolo; Cagli, Barbara; Simone, Pierfranco; Cogliandro, Annalisa; Fortunato, Lucio; Altomare, Vittorio; Trodella, Lucio

    2009-04-01

    The most common surgical approach in case of local tumor recurrence after quadrantectomy and radiotherapy is salvage mastectomy. Breast reconstruction is the subsequent phase of the treatment and the plastic surgeon has to operate on previously irradiated and manipulated tissues. The medical literature highlights that breast reconstruction with tissue expanders is not a pursuable option, considering previous radiotherapy a contraindication. The purpose of this retrospective study is to evaluate the influence of previous radiotherapy on 2-stage breast reconstruction (tissue expander/implant). Only patients with analogous timing of radiation therapy and the same demolitive and reconstructive procedures were recruited. The results of this study prove that, after salvage mastectomy in previously irradiated patients, implant reconstruction is still possible. Further comparative studies are, of course, advisable to draw any conclusion on the possibility to perform implant reconstruction in previously irradiated patients.

  15. No discrimination against previous mates in a sexually cannibalistic spider

    Science.gov (United States)

    Fromhage, Lutz; Schneider, Jutta M.

    2005-09-01

    In several animal species, females discriminate against previous mates in subsequent mating decisions, increasing the potential for multiple paternity. In spiders, female choice may take the form of selective sexual cannibalism, which has been shown to bias paternity in favor of particular males. If cannibalistic attacks function to restrict a male's paternity, females may have little interest to remate with males having survived such an attack. We therefore studied the possibility of female discrimination against previous mates in sexually cannibalistic Argiope bruennichi, where females almost always attack their mate at the onset of copulation. We compared mating latency and copulation duration of males having experienced a previous copulation either with the same or with a different female, but found no evidence for discrimination against previous mates. However, males copulated significantly shorter when inserting into a used, compared to a previously unused, genital pore of the female.

  16. Designing Interfaces

    CERN Document Server

    Tidwell, Jenifer

    2010-01-01

    Despite all of the UI toolkits available today, it's still not easy to design good application interfaces. This bestselling book is one of the few reliable sources to help you navigate through the maze of design options. By capturing UI best practices and reusable ideas as design patterns, Designing Interfaces provides solutions to common design problems that you can tailor to the situation at hand. This updated edition includes patterns for mobile apps and social media, as well as web applications and desktop software. Each pattern contains full-color examples and practical design advice th

  17. All PBL Starts Here: The Problem

    Science.gov (United States)

    Hung, Woei

    2016-01-01

    One essential piece of implementing of PBL is the problem. There have been calls from practitioners in the PBL field for a systematic process for designing effective PBL problems. Yet, the research efforts to explore, develop, and test PBL problem design methods or processes are still sparse. From an instructional designer and researcher's…

  18. Optimum Tolerance Design Using Component-Amount and Mixture-Amount Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Piepel, Gregory F.; Ozler, Cenk; Sehirlioglu, Ali Kemal

    2013-08-01

    One type of tolerance design problem involves optimizing component and assembly tolerances to minimize the total cost (sum of manufacturing cost and quality loss). Previous literature recommended using traditional response surface (RS) designs and models to solve this type of tolerance design problem. In this article, component-amount (CA) and mixture-amount (MA) approaches are proposed as more appropriate for solving this type of tolerance design problem. The advantages of the CA and MA approaches over the RS approach are discussed. Reasons for choosing between the CA and MA approaches are also discussed. The CA and MA approaches (experimental design, response modeling, and optimization) are illustrated using real examples.

  19. Development and problems on concrete technology in Thailand. Effort toward performance-based design and wastes utilization; Tai ni okeru konkurito gijutsu no katten to kongo no mondai. Seino shosagata sekkei to haikibutsu no riyo eno torikumi

    Energy Technology Data Exchange (ETDEWEB)

    Somnuk, Tangtermsirikul [University Thailand, Bangkok (Thailand)

    1999-03-10

    They explained economic crisis and development trend of concrete technology of Thailand in the back and future problem. They introduced growth (GNP) of the economy from 1989 to 1998, growth of the construction business and the cement production quantity and the cement consumption of the interval. In addition, as a design concept of concreting material, they introduced the utilization of the natural and artificial pozzolans (fly ash, steel slag, silica fume, pumice, metakaolin, etc.) as a utilization of a waste to the concrete, when they considered property and strength of the concrete suitable for the climate of Thailand, and they introduced strength of the concrete using these, etc.. (NEDO)

  20. Prostate Problems

    Science.gov (United States)

    ... If you have BPH, you may need to wake up often to urinate when you sleep. If you can’t urinate at all, you should get medical help right away. Your doctor will know if you have a prostate problem based on ...