5,139 research outputs found

    On the Essential Multidimensionality of an Economic Problem: Towards Tradeoffs-Free Economics

    Get PDF
    The foundation of welfare economics is the assumption of Pareto-efficiency and its concept of tradeoffs. Also the production possibility frontier, efficiency frontier, nondominated set, etc., belong to the plethora of tools derived from the Pareto principle. The assumption of tradeoffs does not address the issue of system design or redesign in order to reduce or eliminate tradeoffs as a sure characteristic of suboptimal, inefficient system configuration. In this paper we establish that tradeoffs are not attributes of objectives, criteria or dimensions, as it is habitually assumed, but are the properties of the very sets of possibilities, alternatives or options they purport to value and measure. We use De novo programming, through which the so called feasible set of opportunities can be redefined towards optimal, tradeoffs-free configuration. The implications of tradeoff-free economics are too vast to foresee and elaborate in a single paper; they do touch the very foundations of economic thought. So me numerical examples are given in order to illustrate system-design calculations in linear systems.Tradeoffs, multiple criteria, decision making, tradeoffs-free, optimization, De novo programming, Pareto-efficiency, added value

    Isoperformance An Alternative Design Methodology for Engineering Systems

    Get PDF
    Tradeoffs between performance, cost and risk frequently arise during architecting and design of complex Engineering Systems such as aerospace vehicles. A paradigm shift is occurring from the pure performance optimization approach of the past towards satisfying of performance targets under concurrent risk and cost minimization. This paper proposes ā€œisoperformanceā€ as a set based approach to designing engineering systems by first identifying the acceptable performance invariant set of designs from which a final design is chosen. This is in contrast to a multiobjective cost-risk minimization under performance equality constraints. This paper identifies a number of issues associated with finding the desired performance invariant set, I, given a deterministic or empirical system model that maps design variables x to objective variables J. Isoperformance is presented as a methodology that can quantify and visualize the tradeoffs between determinants (independent design variables) of a known or desired outcome. For deterministic systems the multivariable performance invariant contours can be computed using sensitivity analysis and a contour following algorithm, provided that a mathematical system model of appropriate fidelity exists. In the case of stochastic systems the isoperformance curves can be obtained via a regression analysis, given a statistically representative data set. Once isoperformance curves have been obtained, they are useful in extracting a set of performance invariant solutions. Applying additional objectives, other than performance, can then lead to a set of pareto-optimal designs. Specific examples from opto-mechanical space systems design and human factors are presented

    Review Paper Title: Research & Evaluation of Keyword Search Techniques over Relational Data

    Get PDF
    Currently the relational keyword based searches techniques consider the large number of dataā€™s to provide efficient result while the user searching. There is an issue of limited memory hence there is a need of the implementation of the novel techniques/ algorithm. To improve the search technique process by optimizing the query from that has to contain the memory optimization with the help of the genetic algorithm. The process is executed in the dynamic manner which is considered as the real time scenario in that have to execute the whole process as the dynamic based on the user given query. The proposed system is Research and Evaluation of Keyword Search Techniques over Relational Data. Results indicate that many existing search techniques do not provide acceptable performance for realistic retrieval tasks. Keyword Search with ranking so that our execution time consumption is less, file length and execution time can be seen, ranking can be seen by using chart

    A new and efficient intelligent collaboration scheme for fashion design

    Get PDF
    Technology-mediated collaboration process has been extensively studied for over a decade. Most applications with collaboration concepts reported in the literature focus on enhancing efficiency and effectiveness of the decision-making processes in objective and well-structured workflows. However, relatively few previous studies have investigated the applications of collaboration schemes to problems with subjective and unstructured nature. In this paper, we explore a new intelligent collaboration scheme for fashion design which, by nature, relies heavily on human judgment and creativity. Techniques such as multicriteria decision making, fuzzy logic, and artificial neural network (ANN) models are employed. Industrial data sets are used for the analysis. Our experimental results suggest that the proposed scheme exhibits significant improvement over the traditional method in terms of the timeā€“cost effectiveness, and a company interview with design professionals has confirmed its effectiveness and significance

    An Approach to Analyze Tradeoffs for Aerospace System Design and Operation

    Get PDF
    There are important tradeoffs that need to be considered for the design and operation of aerospace systems. In addition to tradeoffs, there may also be multiple stakeholders of interest to the system and each may have different preferences as to the balance amongst the tradeoffs under consideration. A tradeoff hyperspace is created when there are three or more tradeoff dimensions and this increases the challenge associated with resolving the hyperspace in order to determine the best design and operation of a system. The corresponding objectives of this research are to develop a framework to analyze tradeoff hyperspaces and to account for the preferences of multiple stakeholders in this framework.This work was supported by the National Aeronautics and Space Administration (NASA) under grant NRA- #NNX10AN92A (NASA Ames). The authors are grateful to Dr. Neil Y. Chen and Dr. Banavar Sridhar in the Aviation Systems Division at NASA Ames for their valuable guidance and feedback in managing this project
    • ā€¦
    corecore