• 한국통신학회논문지
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• 제40권10호
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• pp.1931-1933
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• 2015

본 논문은 이종 네트워크 환경에서 무선 통신 시스템의 신뢰성 향상을 위한 인접 셀 간 협력 전송 기법을 제안한다. 이종 네트워크는 현존하는 기술을 사용하여 데이터 전송 속도를 높일 수 있다는 장점이 있다. 하지만 셀 가장자리에서의 통신 성능 저하 현상이 심각한 문제로 대두되고 있다. 따라서 본 논문은 문제 해결을 위해 상황에 따라 적응적으로 전송하는 인접 셀 간 협력 전송 기법을 제시한다.

• 한국학교수학회논문집
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• 제9권2호
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• pp.163-177
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• 2006

수학영재의 창의적 문제해결력 신장을 위한 새로운 교수 학습방법이 요구되고 있다. 이에 본 연구는 과학고 수학반 학생들을 대상으로 사사프로젝트 학습을 실시하여 수학영재들이 어떠한 상황에서 창의성을 발휘하는가, 학습과정에서 벌어지는 영재 상호 간의 교류가 그들의 창의성 신장에 도움이 되는가, 또한 창의적 문제해결력 검사를 실시하고 그 결과 분석을 통해 수학영재들에게 사사프로젝트 학습이 효과성이 있는가를 알아보았다.

• 대한산업공학회지
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• 제21권2호
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• pp.207-216
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• 1995

Constructing a distributed management system has its own advantages in addressing the issue of implementing a quick responsive management system in dynamically changing environment of enterprise. We suggest a basic scheduling methodology applicable to a distributed production management system. A new concept of "flexible schedule" is introduced as a tool to accommodate dynamically changing situations of job shops. Then a search technique (referred to as CSP-CBA search) is presented to obtain such a schedule for the job shop scheduling problem, which is converted into a constraint satisfaction problem(CSP), by using the constraint based analysis(CBA). This approach is tested on more than 100 test problems. The results show that the suggested approach required shorter CPU time and solved more problems in given time than another fixed schedule method.

• 기술경영경제학회:학술대회논문집
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• 기술경영경제학회 2005년도 제26회 동계학술발표회 논문집
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• pp.42-56
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• 2005

Firms cooperating in R&D face a moral hazard problem, because with R&D effort not being observable each partner will focus on its own profit when choosing its effort level. This paper aims to explain the use of optimal license contract for R&D cooperation such as cross-licensing agreement. We argue that in the situations of asymmetric information, the optimal incentive scheme that can solve moral hazard problem is . a linear function of the likelihood ratio. Especially in the case of parallel research, each firm has an extra incentive for cooperative R&D effort, given by the license fee that considers the profit of the cooperating firm, which solely depends on his R&D success if the cooperating firm fails.

• 전기학회논문지
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• 제68권1호
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• pp.159-166
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• 2019

Due to the various engagement situations, it is very difficult to generate the optimal trajectory with several constraints. This paper investigates the sequential convex programming for the impact angle control with the additional constraint of altitude limit. Recently, the SOCP(Second-Order Cone Programming), which is one area of the convex optimization, is widely used to solve variable optimal problems because it is robust to initial values, and resolves problems quickly and reliably. The trajectory optimization problem is reconstructed as convex optimization problem using appropriate linearization and discretization. Finally, simulation results are compared with analytic result and nonlinear optimization result for verification.

• Earthquakes and Structures
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• 제23권5호
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• pp.419-430
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• 2022

The metallic energy dissipation device (EDD) has been widely accepted as a useful tool for passive control of buildings against earthquakes. The distribution of metallic EDDs in a multi-story building may have significant influence on its seismic performance, which can be greatly enhanced if the distribution scheme is properly designed. This paper addresses the optimal distribution problem in the aim of achieving a desired level of performance using the minimum number of metallic EDDs. Five local search heuristic algorithms are proposed to solve the problem. Four base structures are presented as numerical examples to verify the proposed algorithms. It is indicated that the performance of different algorithms may vary when applied in different situations. Based on the results of the numerical verification, the recommended guidelines are finally proposed for choosing the appropriate algorithm in different occasions.

• ETRI Journal
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• 제45권3호
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• pp.492-504
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• 2023

Researchers have recently shown an increased interest in estimating the direction-of-arrival (DOA) of wideband noncircular sources, but existing studies have been restricted to subspace-based methods. An off-grid sparse recovery-based algorithm is proposed in this paper to improve the accuracy of existing algorithms in low signal-to-noise ratio situations. The covariance and pseudo covariance matrices can be jointly represented subject to block sparsity constraints by taking advantage of the joint sparsity between signal components and bias. Furthermore, the estimation problem is transformed into a single measurement vector problem utilizing the focused operation, resulting in a significant reduction in computational complexity. The proposed algorithm's error threshold and the Cramer-Rao bound for wideband noncircular DOA estimation are deduced in detail. The proposed algorithm's effectiveness and feasibility are demonstrated by simulation results.

• 한국수학교육학회지시리즈A:수학교육
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• 제47권4호
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• pp.519-543
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• 2008

The study has been conducted with 29 children from 4th to 6th grades to realize how they understand addition, subtraction, multiplication, and division of whole numbers, and how their understanding influences solving of one-step word problems. Children's understanding of operations was categorized into "adding" and "combination" for additions, "taking away" and "comparison" for subtractions, "equal groups," "rectangular arrange," "ratio," and "Cartesian product" for multiplications, and "sharing," "measuring," "comparison," "ratio," "multiplicative inverse," and "repeated subtraction" for divisions. Overall, additions were mostly understood additions as "adding"(86.2%), subtractions as "taking away"(86.2%), multiplications as "equal groups"(100%), and divisions as "sharing"(82.8%). This result consisted with the Fischbein's intuitive models except for additions. Most children tended to solve the word problems based on their conceptual structure of the four arithmetic operations. Even though their conceptual structure of arithmetic operations helps to better solve problems, this tendency resulted in wrong solutions when problem situations were not related to their conceptual structure. Children in the same category of understanding for each operations showed some common features while solving the word problems. As children's understanding of operations significantly influences their solutions to word problems, they needs to be exposed to many different problem situations of the four arithmetic operations. Furthermore, the focus of teaching needs to be the meaning of each operations rather than computational algorithm.

• 융합정보논문지
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• 제11권11호
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• pp.185-194
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• 2021

이 연구는 COVID-19로 인한 학교 교육의 혼란스러운 상태를 파악하고, 국가적 위기에 신속하게 대처하기 위한 학교장의 역할을 모색하는 것을 목적으로 한다. 이를 해결하기 위하여 서울·부산·대구·대전·제주지역 초등학교 교장 34명을 대상으로 COVID-19에 대처하기 위해 학교장에게 어떤 리더십이 필요한지를 1차 SNS를 통해 개방형 문항으로 설문을 하고, 2차는 전화를 통해 심층 면접을 진행했다. 뉴노멀 시대에 교장의 리더십은 위기 상황에 신속하게 대응할 수 있는 능력과 신속한 예산 확보 및 투입, 교원 간 소통 촉진으로 발생할 수 있는 교육활동 지원, 수업 지원, 문제 예방 등에 대한 통찰력 있고, 책임 있는 리더십이 필요하다는 조사 결과가 나왔다. COVID-19과 같은 위기 상황에서 학교가 안정적으로 대처할 수 있는 학교장 역할을 정립하고 안전한 환경에서 학생의 배움이 일어나는 교육 환경 구축이 필요하다. 이를 위해서는 국가적, 교육 정책적 지원이 필요하다.

• 한국융합학회논문지
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• 제10권5호
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• pp.267-278
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• 2019

본 연구의 목적은 불완전한 가족 구성원의 형태로서 결손가정인 동시에 학업과 운동을 함께 병행하는 학생선수 들의 '역경극복 과정'에 대해 심층적으로 이야기하고 분석하는데 있다. 이러한 연구 목적의 달성을 위해 내러티브 탐구(narrative inquiry) 방법을 실시하였고, 그 결과는 다음과 같다. 첫째, 대인관계의 개선 및 확대와 관련하여 이들은 일상생활에서 자신 있게 행동하고 적극적인 성격으로 변화할 수 있게 되었다. 둘째, 즐거움을 통한 긍정적 정서형성과 관련하여 역경 상황의 개선을 위해 무엇을 해야 하는지 본인이 적극적인 탐색과 함께 스스로의 감정을 조절하였다. 셋째, 문제해결력의 향상과 관련하여 결손으로 인한 역경 상황에서 자신에게 가장 맞는 효과적인 방법의 발견과 미래의 역경상황에 적합한 방법을 선택할 수 있는 문제해결에 대한 능력이 향상된 것을 확인 할 수 있었다.