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Modern Capital Theory and Optimal Fisheries Management (현대자본이론과 최적어업관리)

  • 박장일
    • The Journal of Fisheries Business Administration
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    • v.23 no.2
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    • pp.53-67
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    • 1992
  • It has been recognized, virtually from the time of its inception, that fisheries economics, like other aspects of resource economics, should ideally be cast in capital-theoretic terms. The fish population or biomass can be viewed as a capital stock in that, like conventional or man-made capital, it is capable of yielding a sustainable consumption flow through time. This study is to introduce the optimal control theory which was extended from the theory of calculus of variations into the study of former static theory of fisheries economics started by Gordon (1954). The optimal control theory eliminated the inadequacies of the classical techniques to a large extent. From this point of view, this study, on the base of Schaefer model, summerizes most of major results achieved so far, but does so in a manner such that the links with capital theory are made transparent. This study explores two sets of problems. The first concerns the optimal approach to the equilibrium stock, i.e. the optimal investment policy. The second set of problems arises from the relaxation of the highly restrictive assumption of autonomy (i.e. the assumption that the parameters are independent of time), then concludes the relaxation of linearity assumption together with the complexities caused by that.

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양력선 이론을 이용한 EDISON CFD 해석자의 검증

  • Kim, Tae-Hui
    • Proceeding of EDISON Challenge
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    • 2016.11a
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    • pp.101-105
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    • 2016
  • Prandtl's Lifting-line theory is the classical theory of calculating aerodynamic properties. Though it is classical method, it predicts the aerodynamic properties well. By lifting-line theory, high aspect ratio is critical factor to decrease induced drag. And 'elliptic-similar' wing also makes the minimum induced drag. But due to the problem of manufacturing, tapered wing is preferred and have been utilized. In this Paper, by using Edison CFD, verifying the classical lifting-line theory. To consider induced drag only, using Euler equation as governing equation instead of full Navier-Stokes equation. Refer to the theory, optimum taper ratio which makes the minimum induced drag is 0.3. Utilizing the CFD results, plotting oswald factor over various taper ratio and investigating whether the consequences are valid or not. As a result, solving Euler equation by EDISON CFD cannot guarantee the theoretical values because it is hard to set the proper grid to solve. Results are divided into two cases. One is the values are decreased gradually and another seems to following tendency, but values are all negative number.

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Study on the Concept of Monarch-fire(君火) and Ministerial-fire(相火) in Zhu Dan-Xi(朱丹溪)'s Ministerial-fire Theory(相火論) (주단계(朱丹溪) 상화론(相火論)의 군화(君火) 상화(相火)의 개념에 대한 고찰)

  • Lee, Yong-Bum
    • Journal of Korean Medical classics
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    • v.27 no.4
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    • pp.29-38
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    • 2014
  • Objectives : In ministerial-fire theory(相火論) of Zhu Dan-Xi(朱丹溪), the meanings of monarch-fire(君火) and ministerial-fire(相火) described in papers published nowadays are not the same. Therefore, it is necessary to rebuild a clear concept. Methods : To understand the relationships among 'heaven(天)'-'human(人)' and 'name(名)'-'position(位)', the core concept of the ministerial-fire theory(相火論) of Zhu Dan-Xi(朱丹溪), I examined the relationships between 'heaven(天)' and 'human(人)' in Neo-Confucianism(性理學) of Song(宋) Dynasty and reviewed the notes of Wang Bing(王冰) which were quoted by Zhu Dan-Xi(朱丹溪) to set the concept of monarch-fire(君火) and ministerial-fire(相火). I studied relevant texts. Results : In ministerial-fire theory(相火論) of Zhu Dan-Xi(朱丹溪), monarch-fire(君火) is perceived as being from greed(人欲) that can cause hyperactivity(妄動) of ministerial-fire(相火), whereas ministerial-fire(相火) is perceived as being able to control monarch-fire(君火) by following the orders from heaven. This point of view is different from the past which recognized monarch-fire (君火) as the owner and ministerial-fire(相火) as the servant. Conclusions : Zhu Dan-Xi(朱丹溪) received the ideological impact of Neo-Confucianism, and accepted the notes of Wang Bing, recognized monarch-fire(君火) as 'name(名)' and ministerial-fire(相火) as 'position(位)', so he voiced the ministerial-fire theory(相火論) that perceived monarch-fire(君火) as fire(火) of the five processes(五行) of human body that came from greed, ministerial-fire(相火) as being in a position to hear the order from the 'heaven(天)' to control monarch-fire(君火). But the concept of ministerial-fire(相火) which he set connoted a confusing meaning of 'nature(性)' and 'way(道)' of Neo-Confucianism. In the later process to solve the problem, life-gate theory(命門學說) was raised, and many researchers had tried to remove the meaning of hyperactivity from the ministerial-fire(相火).

Mechanism and Application Methodology of Mental Practice (정신 연습의 기전과 적용 방법)

  • Kim Jong-soon;Lee Keun-heui;Bae Sung-soo
    • The Journal of Korean Physical Therapy
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    • v.15 no.2
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    • pp.75-84
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    • 2003
  • The purpose of this study was to review of mechanism and application methodology about mental practice. The mental practice is symbolic rehearsal of physical activity in the absence of any gross muscular movements. Human have the ability to generate mental correlates of perceptual and motor events without any triggering external stimulus, a function known as imagery, Practice produces both internal and external sensory consequences which are thought to be essential for learning to occur, It is for this reason that mental practice, rehearsal of skill in imagination rather than by overt physical activity, has intrigued theorists, especially those interested in cognitive process. Several studies in sport psychology have shown that mental practice can be effective in optimizing the execution of movements in athletes and help novice learner in the incremental acquisition of new skilled behaviors. There are many theories of mental practice for explaining the positive effect In skill learning and performance. Most tenable theories are symbolic learning theory, psyconeuromuscular theory, Paivio's theory, regional cerebral blood flow theory, motivation theory, modeling theory, mental and muscle movement nodes theory, insight theory, selective attention theory, and attention-arousal set theory etc.. The factors for influencing to effects of mental practice are application form, application period, time for length of the mental practice, number of repetition, existence of physical practice.

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Locating-Hop Domination in Graphs

  • Canoy, Sergio R. Jr.;Salasalan, Gemma P.
    • Kyungpook Mathematical Journal
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    • v.62 no.1
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    • pp.193-204
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    • 2022
  • A subset S of V(G), where G is a simple undirected graph, is a hop dominating set if for each v ∈ V(G)\S, there exists w ∈ S such that dG(v, w) = 2 and it is a locating-hop set if NG(v, 2) ∩ S ≠ NG(v, 2) ∩ S for any two distinct vertices u, v ∈ V(G)\S. A set S ⊆ V(G) is a locating-hop dominating set if it is both a locating-hop and a hop dominating set of G. The minimum cardinality of a locating-hop dominating set of G, denoted by 𝛄lh(G), is called the locating-hop domination number of G. In this paper, we investigate some properties of this newly defined parameter. In particular, we characterize the locating-hop dominating sets in graphs under some binary operations.

Mix Design of High Performance Concrete Using Maximum Density Theory (최대 밀도 이론을 이용한 고성능콘크리트의 배합 설계)

  • Lee, Seung-Han;Jung, Yong-Wook
    • Journal of the Korea Concrete Institute
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    • v.19 no.3
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    • pp.377-383
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    • 2007
  • In recent years the field application of high performance concrete has been increased to improve the quality and reliability of concrete structures. The mix design of the high performance concrete includes the 2 set-off mixture theory of mortar and coarse aggregate and that of paste and aggregate. The 2 set-off mixture theory of mortar and coarse aggregate has a problem of having to determine its value through repeated experiments in applying the rheological characteristics of mortar. The 2 set-off mixture theory of paste and aggregate has never been applied to high performance concrete since it doesn't take into account the relationship between optimum fine aggregate ratio and unit volume of powder nor does it consider the critical aggregate volume ratio. As the mixture theory of these high performance concretes, unlike that of general concrete, focuses on flowability and charge-ability, it does not consider intensity features in mix design also, the unit quantity of the materials used is determined by trial and error method in the same way as general concrete. This study is designed to reduce the frequency of trial and error by accurately calculating the optimum fine aggregate ratio, which makes it possible to minimize the aperture of aggregate in use by introducing the maximum density theory to the mix design of high performance concrete. Also, it is intended to propose a simple and reasonable mix design for high performance concrete meeting the requirements for both intensity and flowability. The mix design proposed in this study may reduce trial and error and conveniently produce high performance concrete which has self-chargeability by using more than the minimum unit volume of powder and optimum fine aggregate with minimum porosity.

Methods and Procedures of Ordering Theory and Hierarchical Analysis of Science Process Skills Using Ordering Theory (서열화 이론의 방법과 절차 및 이를 이용한 과학탐구기능 요소의 위계분석)

  • Lim, Cheong-Hwan
    • Journal of The Korean Association For Science Education
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    • v.12 no.3
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    • pp.91-107
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    • 1992
  • The Purpose of this study was to present the procedures and methods of ordering theory,and to search for a learning hierarchy among science process skills in each Piagetian cognitive reasoning level. One of the purpose of this is not to determine the clear and exact hierarchy but rather to demonstrate how ordering theoretic methods and procedures can be used to determine the hierarchy of logical relationships among a set of test items or the testing of a hypothesized hierarchy. Ordering theory was used to analyze five science process skills collected from 509 high school students. Ordering Theory has as its primary intent either the testing of hypothesized hierarchies among items at the determination of hierchies among items. Hierarchical relationships were identified within five science process skills. The results will be helpful in giving useful inform at ions to classroom teachers and science curriculum developer.

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