• 한국수학교육학회지시리즈D:수학교육연구
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• 제14권3호
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• pp.195-209
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• 2010

Utilizing a structure of operations known as Dissection-Motion-Operations (DMO), a set of mathematics propositions or area-formulas in school mathematics will be introduced through shape-to-shape transforms. The underlying theme for DMO is problem-solving through visual reasoning and proving manipulatively or electronically vs. rote learning and memorization. Visual reasoning is the focus here where two operations that constitute DMO are utilized. One operation is known as Dissection (or Decomposition) operation that operates on a given region in 2D or 3D and dissects it into a number of subregions. The second operation is known as Motion (or Composition) operation applied on the resultant sub-regions to form a distinct area (or volume)-equivalent region. In 2D for example, DMO can transform a given polygon into a variety of new and distinct polygons each of which is area-equivalent to the original polygon (cf [Rahim, M. H. & Sawada, D. (1986). Revitalizing school geometry through Dissection-Motion Operations. Sch. Sci. Math. 86(3), 235-246] and [Rahim, M. H. & Sawada, D. (1990). The duality of qualitative and quantitative knowing in school geometry, International Journal of Mathematical Education in Science and Technology 21(2), 303-308]).

• 디지털콘텐츠학회 논문지
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• 제8권2호
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• pp.235-243
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• 2007

수학과의 학습은 학습자가 구체적인 조작을 통해서 개념을 학습한다. 그러나 웹에서 구현되는 대부분의 콘텐츠들은 정적이며 학습자와의 상호작용에 제약이 많다. 이런 제약 조건을 극복하고 학생들의 인지적인 단계에 적합한 동적인 상호작용을 위한 콘텐츠 개발이 필요하다. 이에 본 연구에서는 초등수학에서 수와 연산 영역의 교육과정 분석하였다. 이를 기반으로 객체지향설계원리를 이용하여 학습 애플릿에 필요한 "수 클래스"를 설계하고 구현하였으며, 구현된 "수 클래스"를 기반으로 클래스기반 "수와 연산 학습 애플릿"을 개발하였다. 클래스기반 '수와 연산 학습 애플릿'은 초등학교 수학과의 '수와 연산' 영역 교육과정을 토대로 학습 주제를 선정하였으며, 각 학습 주제에 따라 소단위 프로그램으로 제작하였다. 이 학습 애플릿은 자유로운 조작과 탐구활동을 통해 수와 연산의 개념과 원리를 학습할 수 있도록 한다. 이것은 학생들의 동적인 상호 작용을 강화한다.

• 한국경영과학회지
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• 제23권3호
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• pp.75-90
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• 1998

The improper use of input and output factors in DEA has a critical and negative impact on the efficiency measurement and the discernment of decision making units(DMUs) : hence the proper selection Process of the factors should precede the actual applications of DEA. In this paper, we propose a new approach to selecting proper factors based on Tofallis' partial efficiency evaluation method(1996). With the approach, the factors aye clustered by measuring their respective partial efficiencies and analyzing the rank correlations of them. The method and procedure we propose in this paper are then applied to measure the efficiencies of the public libraries in Seoul District area, and the results show that the proposed approach can provide meaningful information to improve discernment of the DMUs while using less number of input factors (and less information). The proposed method can be effectively used in the situation where the number of the DMUs to be considered is relatively small compared to the number of available input and output factors, which usually lessens the power to identify the inefficient units in DEA.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 1997년도 추계학술대회발표논문집; 홍익대학교, 서울; 1 Nov. 1997
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• pp.239-242
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• 1997

Subscriber network investment cost is a main cost element among those constituting the access charges in telephone networks. The purpose of this paper to estimate the investment cost of installing a subscriber network in a typical metropolitan area and to develop a cost modeling framework. To this aim, a metropolitan area in Seoul was investigated. The main cost elements were identified and their relationships with the cable technology, geographical characteristics, and the number of subscribers were analyzed. The findings could be used to design an enhanced cost proxy models for estimating the access charges in a multi-operator environment.

• 한국국방경영분석학회지
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• 제5권1호
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• pp.37-72
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• 1979

This paper presents the FORTRAN program for expected damage by surface-to-surface weapons. One of the methods can be used to determine the effectiveness of general purpose (GP) bombs and cluster weapons against single unitary targets, linear targets, area targets, and areas of unitary target elements, The effectiveness index is in terms of fractional damage ($F_D$) or the number of volleys ($N_V$).

• 한국경영과학회지
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• 제40권2호
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• pp.63-77
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• 2015

The territorial air that our sovereignty is being applied to is divided into several zones and areas. In order to use and manage them effectively, these zones and areas have laws, regulations and rules. The number of airspaces (MOA : Military Operation Area) and Ranges that are used in the military are limited and many airbases are being used for training. Currently the central department manages some, and the rest are independent airbases. Therefore, efficient allocation is not performed and the result occurs where airspaces and ranges are allocated unnecessarily. This is increasing the workload of staff leading to unnecessary re-work. To slove problem, this study proposed models for allocating airspaces and ranges using goal programming with multi-objective functions of minimizing the deviations of the target values.

• 시스템엔지니어링학술지
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• 제11권1호
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• pp.73-79
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• 2015

This paper describes boundary analysis for modeling Aircraft Carrier Sortie Generation System(CVSGS). An aircraft carrier, as a super system, is a warship going into battle by operating a number of aircraft on deck and it should be lay down a definition about aviation operations interacting between aircraft carrier and carrier air wing in small deck area. For this reason this paper models common aviation support system for generating sortie basic unit of carrier aviation operations unlike to general warship and defines boundaries between this system and aircraft carrier and carrier air wing. This paper analysis activities of aircraft carrier and embarked carrier air wing in carrier aviation operations, and analysis and defines boundaries Aircraft Carrier Sortie Generation System(CVSGS) to perform core functions in interacting between aircraft carrier and embarked carrier air wing.

• 한국수학교육학회지시리즈A:수학교육
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• 제62권4호
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• pp.515-529
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• 2023

본 연구의 목적은 초등학교 수학과 교육과정의 3~6학년 수와 연산 영역에 대한 교사들의 이해 실태를 분석하고, 교사들의 교육과정에 대한 이해를 개선하기 위한 시사점을 도출하는 것이다. 이를 위해 초등 교사들에게 교육과정 성취기준을 학년 단위로 평가할 수 있는 문항을 개발하도록 하고, 개발된 문항에서 나타나는 교사들의 교육과정에 대한 이해 실태를 살펴보았다. 연구 결과 수집된 문항 중 약 25%에 해당하는 문항에서 성취기준을 잘못 해석한 부분이 있었으며, 대표적으로 교과서를 기준으로 볼 때 각 학년에서 다루는 내용을 혼동하거나, 두 개의 성취기준에서 다루는 내용의 차이를 완전하게 구분하지 못하는 경우 등이 나타났다.

• 한국국방경영분석학회지
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• 제17권1호
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• pp.159-176
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• 1991

The probability of target survival is the most important factor in the target assignment, Most of the studies about it have assumed the case of one target and ane weapon type. Therefore, they can not be applied to the real situation. In this paper. the quantity and type of enemy assets of the friendly force are considered simultaneously. Considered defense type is the coordinated defense with no impact point prediction. The objective function is to minimize the expected total survival value of targets which are scattered in the defense area. The rules of aircraft assignment are as follows : first, classify targets into several groups, each of those has the same desired damage level secondly. select the critical group which has the least survival value in accordance with the additional aircraft assignment, and finally. assign the same number of attack assets against each target in the critical group. In this paper, the attack assets, the escort assets, and the defense assets are considered. The model is useful to not only the simple aircraft assignment problem but also the complicated wargame models.

• 경영과학
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• 제31권4호
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• pp.135-150
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• 2014

This paper analyzes the operational efficiency of 91 individual retail stores in Seoul by a two-step procedure. In the first step, a data envelopment analysis (DEA) model is used to identify the efficiency scores. Three inputs (store size, number of items, and number of employees) and two outputs (sales and number of customers) are used for the efficiency measurement. In the second step, a Tobit regression model is used to identify the drivers of efficiency. DEA efficiency scores are used to test hypotheses on the impact of five independent variables, namely store age, number of items per store size, number of items per employee, trade area index, and number of competitors. Results of the Tobit analysis show that number of items per store size, number of items per employee, and number of competitors play a significant role in influencing the operational efficiency of retail stores. Managerial implications of the study are discussed.