• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.5
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• pp.467-476
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• 2010

For the very light jet aircraft design, the design baseline configuration has been selected using the logical decision making process, and the design optimization problem is formulated by considering the airworthiness regulations as design constraints. Airworthiness regulations are the minimum requirements for the safe aircraft flight and must be considered from the conceptual design stage. After carefully selecting the airworthiness constraints and the user specified requirements, a series of design making models including the affinity diagram, nested column diagram, quality function deployment (QFD), Pugh concept selection matrix, are used to find and evaluate alternative configuration baselines. From the feasible design space searching process, the best altenative design, which satisfies the airworthiness constraints while excluding the user subjective decisions as much as possible, has been successfully derived.

• Journal of the Society of Naval Architects of Korea
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• v.36 no.3
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• pp.107-114
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• 1999

Design Axiom proposed by N. P. Such consists of Independence Axiom & Information Axiom. Based on the Independence Axiom, it is very useful specially for early design stage such as conceptual design to generate the design alternatives by considering both functions and structures of product. Since the Information Axiom shows that the design solution should have a least information to be the best one among the many alternatives, this axiom can be used for the best selection purpose during the preliminary design stage. In this paper, the possibility of Design Axiom in marine design application is checked by carrying out three examples of marine design. In the conceptual design of thruster, it is proven to use the Independence Axiom very effective by relating directly functional requirements with design parameters, one by one. In main engine selection example, Information Axiom is used to select best solution among alternatives by choosing the one having the minimum information quantity. For similarity based design in which the selection of changing design variables and the amount of those are important, it is proved that design axiom applied to Barge design case would be very effective and useful. As functional requirements and constrains were not clarified in early design stage, design axiom shows some difficulty for larger system design like ship which is basically carried out by an incremental and iterative process.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.11C
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• pp.1055-1063
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• 2002

In this paper, we have studied path selection problem using multiple metric. Current Internet selects a path using only one metric. The path selected by one metric is a best-effort service that can satisfy one requirements. In order to satisfy a call with various Qualify-of-Service(QoS) requirements, the path must satisfy multiple constraints. In many cases, path selection is NP-complete. The proposed algorithm is widest-least cost routing algorithm that selects a path based on cost metric which is basically a delay metric influenced by the network status. The proposed algorithm is a multiple metric path selection algorithm that has traffic distribution ability to select shortest path when network load is light and move traffic to other alternate path when the link load is high. We have compared the results with other routing algorithms.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.12
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• pp.1705-1710
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• 2003

A small body size of Brown Tsaiya laying duck is desirable to reduce maintenance requirements, so the body weight at 40 weeks of age (BW40) has to be maintained at its current level. Egg weight has to be maintained at around 65 g to meet market requirements. Eggshell strength at 40 weeks of age (ES40) must to be increased in order to maintain a low incidence of broken eggs. Thus, number of eggs laid up to 52 weeks of age (EN52) has to be increased without negative correlated response on ES40. A new linear genetic selection index was used: $I_g=a_0{\times}GEW40\;(g)+a_1{\times}GBW40\;(g)+a_2{\times}GES40\;(kg/cm^2)+a_3{\times}GEN52\;(eggs)$ where GEW40, GBW40, GES40 and GEN52 were the multitrait best linear unbiased prediction (MT-BLUP) animal model predictors of the breeding values respectively of egg weight and body weight at 40 weeks of age (EW40, BW40), ES40 and EN52. The coefficients $a_0$, $a_1$, $a_2$ and $a_3$ were calculated with constraints of 0.0 g, 0.0 g and $0.013kg/cm^2$ for expected genetic gains in EW40, BW40 and ES40 respectively and maximum gain in EN52. Since 1997, the drakes and the ducks were selected according to their own indexes, with this new genetic selection index. From G0 to G4, the average per generation predicted genetic responses in female duck were +0.05 g for EW40, +0.92 g for BW40, $+0.035kg/cm^2$ for ES40 and +2.13 eggs for EN52. Which represented respectively 0.07%, 0.06%, 0.67% and 1.0% of the means of the EW40, BW40, ES40 and EN52. For ES40 and EN52, it represented also respectively 16.1% and 21.6% of the additive genetic standard deviation of these traits. Thevse results indicated that selection of laying Brown Tsaiya by a restricted genetic selection index and with MT-BLUP animal model could be an efficient tool for improving the efficiency of egg production, increasing egg shell strength and egg number while holding egg weight and body weight constants.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.05a
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• pp.876-881
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• 2004

Finite element model updating is an inverse problem to identify and correct uncertain modeling parameters that leads to better predictions of the dynamic behavior of a target structure. Unlike other inverse problems, the restrictions on selecting parameters all: very high since the updated model should maintains its physical meaning. That is, only the regions with modeling errors should be parameterized. And the variations of the parameters should be kept small while the updated results give acceptable correlations with experimental data. To avoid an ill-conditioned numerical problem, the number of parameters should be kept as small as possible. Thus it is very difficult to select an adequate set of updating parameters which meet all these requirements. In this paper, the importance of updating parameter selection is illustrated through a case study, and an automated procedure to guide the parameter selection is suggested based on simple observations. The effectiveness of the suggested procedure is tested with two example problems, ones is a simulated case study and the other is a real engineering structure.

• The Journal of the Korea Contents Association
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• v.10 no.5
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• pp.1-9
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• 2010

This paper propose a novel scheme called selective evaluation to improve convergence of ACO (ant colony optimization) for feature selection. The scheme cutdown the computational load by excluding the evaluation of unnecessary or less promising candidate solutions. The scheme is realizable in ACO due to the valuable information, pheromone trail which helps identify those solutions. With the aim of checking applicability of algorithms according to problem size, we analyze the timing requirements of three popular feature selection algorithms, greedy algorithm, genetic algorithm, and ant colony optimization. For a rigorous timing analysis, we adopt the concept of atomic operation. Experimental results showed that the ACO with selective evaluation was promising both in timing requirement and recognition performance.

• Journal of KIISE:Software and Applications
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• v.33 no.7
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• pp.615-623
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• 2006

A non-functional requirement is a property or quality that the proposed systems have to support the functional requirements. A non-functional requirement is reflected by quality attribute These non-functional requirements playa crucial role during system development, serving as selection criteria for choosing among decisions. It should be continuously considered through the software development process. In spite of the importance of the non-functional requirements, it received little attention because of ambiguousness and invisibility of non-functional requirements. Therefore non-functional model which is a process to analyze the non-functional requirement is proposed for improving the management efficiency of non-functional requirements. Also, this paper presents the trace among the UML diagrams to the conceptual model. According to the non-functional requirement development process, this paper achieved performance-based case study. After then, non-functional requirement should be traced using the UML diagrams.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.11
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• pp.2593-2599
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• 2014

The way of mobile apps development using open source software have been becoming increasingly popular recently. In opensource mobile User Interface components case, there is tends to much more be used than mobile functional components. Because it is more easier that the reusability for implementation of User Interface. The problem is to apply as an open source mobile components selected for this reason all of the existing two studies. It is an open source software selection process and selection procedures shelf components. We revise to conform to existing mobile components selected for the study on open source software selection process in this paper. Can help increase the productivity of the mobile app development by the open source components to meet the functional requirements when developing mobile apps that can be easily retrieved and presented the selection process of this study is effective.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.4
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• pp.1817-1836
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• 2020

Network convergence is considered as one of the key solutions to the problem of achieving future high-capacity and reliable communications. This approach overcomes the limitations of separate wireless technologies. Efficient interface selection is one of the most important issues in convergence networks. This paper solves the problem faced by users of selecting the most appropriate interface in the heterogeneous radio-access network (RAN) environment. Our proposed scheme combines a hierarchical evaluation of networks and game theory to solve the network-selection problem. Instead, of considering a fixed weight system while ranking the networks, the proposed scheme considers the service requirements, as well as static and dynamic network attributes. The best network is selected for a particular service request. To establish a hierarchy among the network-evaluation criteria for service requests, an analytical hierarchy process (AHP) is used. To determine the optimum network selection, the network hierarchy is combined with game theory. AHP attains the network hierarchy. The weights of different access networks for a service are calculated. It is performed by combining AHP scores considering user's experienced static network attributes and dynamic radio parameters. This paper provides a strategic game. In this game, the network scores of service requests for various RANs and the user's willingness to pay for these services are used to model a network-versus-user game. The Nash equilibria signify those access networks that are chosen by individual user and result maximum payoff. The examples for the interface selection illustrate the effectiveness of the proposed scheme.

• Journal of the Korean Operations Research and Management Science Society
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• v.39 no.2
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• pp.83-95
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• 2014

In this paper, we develop a portfolio selection model that can be used to invest in markets with margin requirements such as the foreign exchange market. An investment algorithm to implement the proposed portfolio selection model based on objective historical data is also presented. We further conduct empirical analysis on the performance of a hypothetical investment in the foreign exchange market, using the proposed portfolio selection model and investment algorithm. Using 7 currency pairs that recorded the highest trading volume in the foreign exchange market during the most recent 10 years, we compare the performance of 1) the Dollar Index, 2) a 1/N Portfolio which equally allocates capital to all N assets considered for investment, and 3) a hypothetical investment portfolio selected and managed according to the portfolio selection model and investment algorithm proposed in this paper. Performance is compared in terms of accumulated returns and Sharpe ratios for the 10-year period from January 2003 to December 2012. The results show that the hypothetical investment portfolio outperforms both benchmarks, with superior performance especially during the period following financial crisis. Overall, this paper suggests that a mathematical approach for selecting and managing an optimal investment portfolio based on objective data can achieve outstanding performance in the foreign exchange market.