• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권5호
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• pp.1654-1675
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• 2014

In practical wireless systems, the erroneous channel state information (CSI) sometimes deteriorates the performance drastically. This paper focuses on robust design of coordinated set planning of coordinated multi-point (CoMP) transmission, with respect to the feedback delay and link error. The non-ideal channel models involving various uncertainty conditions are given. After defining a penalty factor, the robust net ergodic capacity optimization problem is derived, whose variables to be optimized are the number of coordinated base stations (BSs) and the divided area's radius. By the maximum minimum criterion, upper and lower bounds of the robust capacity are investigated. A practical scheme is proposed to determine the optimal number of cooperative BSs. The simulation results indicate that the robust design based on maxmin principle is better than other precoding schemes. The gap between two bounds gets smaller as transmission power increases. Besides, as the large scale fading is higher or the channel is less reliable, the number of the cooperated BSs shall be greater.

• International Journal of Contents
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• 제16권1호
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• pp.25-33
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• 2020

We develop a simulation method that affords very high variability of virtual pedagogical situations involving many independent plans, still achieves authoring (or implementation) scalability. While each individual plan would be coherently drawn up by an agent for its respective goal, those independently-made plans might be coincidentally intertwined in their execution. The inevitable non-determinism involved in this multi-event plan encompassing pre-planned and unforeseen events is resolved by (multi-phase) dynamic planning and articulated sequencing of events in contrast to static planning and monolithic authoring in conventional narrative systems. Connections between events are dictated by their associated rules and their actual connections are dynamically determined in execution time by current conditions of background-world. This unified connection scheme across pre-planned and unforeseen events allows a multi-plan, multi-agent situation to be coherently planned and executed in a global scale. To further the variability of a situation, the inter-event coupling is made in a fine level of action along with a limited episteme of each agent involved. We confirm analytically the viability of our approach with respect to the situation variability and authoring scalability, and demonstrate its practicality with an implementation of a composite situation.

• 한국전자거래학회지
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• 제20권3호
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• pp.29-46
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• 2015

정부의 연구개발에 대한 기획 정책이 변화함에 따라 국가 R&D 지식 네트워크가 어떻게 변동하였는지에 대해 살펴보고자 한다. 이를 위해 본 연구는 산업통상자원부의 산업융합원천 기술개발사업에 참여하는 각 주체들 간의 네트워크를 시기별로 분석하였다. 산업융합원천기술개발사업의 기획 정책은 2012년 전후를 기점으로 바뀌게 되는데 2012년 이전에는 '기획위원' 중심으로 기획 과제를 선정하다가 2012년 이후에는 'PD' 중심으로 과제를 기획하는 시스템으로 바뀐다. 이에 따라 우선, '기획위원' 제도에 따른 R&D 네트워크를 분석하고자 2009년부터 2011년까지의 현황을 살펴보고, 이후 'PD' 제도도입에 따른 R&D 네트워크 변동을 분석하고자 2012년부터 2013년까지의 현황으로 시기를 나누어 분석하였다. 분석 결과 PD 제도 도입 이후 셀프관계(기획자가 본인이 기획한 과제를 과제 참여자로 직접 수행하는 형태)가 대폭 개선되는 등 효과가 나타났음을 파악할 수 있었다. 셀프관계가 많을수록 신진학자에게는 기획의 불평등이 존재한다는 점을 고려할 때 PD 제도의 도입은 긍정적인 효과를 가져왔다고 볼 수 있다. 이러한 연구는 정부의 기획 정책 변화에 따른 효과를 계량적으로 분석하여 성과를 제고하고 향후 R&D정책의 방향을 제시한다는 점에서 의미가 있다고 본다.

• 한국건설관리학회논문집
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• 제24권1호
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• pp.3-11
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• 2023

현재 국내에서는 건설공사 사후평가 제도에 따라 사업 준공 후 공사내용 및 그 효과를 조사하여 프로젝트의 성과를 평가하고 향후 계획된 유사 건설사업의 효율적인 수행을 위한 자료로 활용하고 있다. 그러나 건설사업의 성과를 보다 효과적으로 관리하기 위해서는 프로젝트 진행 과정에서 단계별 성과를 평가하여 그에 따른 유연한 관리전략을 수립할 수 있어야 한다. 따라서 건설사업의 효율적인 성과관리를 위해서는 건설사업 단계별 성과평가체계가 필요하다. 본 연구는 건설사업 초기단계의 성과를 평가할 수 있는 계획단계 벤치마킹을 위한 기초 모델을 제시하고자 한다. 이를 위하여 본 연구에서는 한국개발연구원에서 제공하고 있는 예비타당성 조사 보고서 중 완료된 도로공사 354건에 대해 데이터베이스를 구축하였다. 계획단계 성과를 평가할 성과지표로 시설용량을 기준으로 한 표준공사비와 표준공사기간 지표를 개발하여 도로사업의 계획단계의 성과를 분석할 수 있는 벤치마킹 모델을 제시하였다. 이를 통해 도로사업 계획단계의 표준공사비 및 표준공사기간을 산정하고, 도로사업의 특성별 차이를 분석하였다. 본 연구의 결과를 활용하여 계획단계의 성과와 설계 및 시공단계의 성과를 연계하여 분석한다면 건설사업 생애주기 동안의 성과관리가 가능할 것으로 기대된다.

• 한국건설관리학회논문집
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• 제8권1호
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• pp.124-131
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• 2007

공정관리는 일정 계획에 따라 공사의 진도를 관리하는 것뿐만 아니라 프로젝트를 주어진 공기 내에 완성하기 위하여 시공 방법 및 계획을 마련하고 이에 따른 장비, 자재, 인원 등에 대한 계획을 수립하는 것을 포함한다. 본 연구는 실제 고속도로 건설공사 중 포장공정의 계획 수립에 있어서 린 콘크리트 포장작업과 콘크리트 슬래브 포장작업을 대상으로 시뮬레이션 모델을 개발하고 이를 이용하여 공정계획을 수립하는 방안을 제시하고 있다. 또한, 시뮬레이션 모델을 이용하여 수립된 계획과 해당 현장의 기존 포장공정 계획을 비교함으로서 비용과 공기 측면에서 보다 생산적이고 효율적인 대안의 수립에 시뮬레이션 기법이 효과적인 방법론이 될 수 있음을 보여 준다. 결국, 본 연구를 통해 건설공사의 시공 계획을 수립하는 초기단계에서 시뮬레이션 모델을 구축하여 체계적이고 과학적인 분석을 수행하게 되면 보다 효율적이고 생산적인 건설공정 계획 및 관리가 가능하다는 사실을 확인하고 있다.

• 농촌계획
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• 제12권3호
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• pp.1-11
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• 2006

After the 2000's, the rural village development projects are designated as participatory rural village development programs and projects. The purpose of this study is to draw a scheme to facilitate resident's participation in rural village development project by exploring the factors influencing resident's participation. For this, in Namsa rural theme village in Dansung-myon, Sanchung-gun, Kyongnam Province, the data were collected through field surveys and interviews residents residing in this village. In addition, observations studies and an opinion survey of the persons concerned in the presentation meetings were also conducted. I investigated and analysed the activation factors and the characteristics of residents' participation, and amenity resources which were essential for community planning including the planning-establishment, theme-searching and development of experience program. Through this study, I drew findings as follows; 1) The leader's leadership and residents' positive participation are very important activation factors in the first stage of rural viability. 2) And then, the external support and concern, the establishment of short-and long-term community planning, and the rural-income increase through the development of amenity resources play important roles as activation factors in the successive stage of rural viability. Based on the results of this study, the following recommendations were made. In order to improve the level of resident's participation in rural village development programs and projects, it is necessary to evaluate their successes, failure, barriers and the positive correlation between their success more delicately. In addition to this, it must be suggested the better model for participatory rural village development programs for the further enhancement and improvement of rural village development projects.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2005년도 추계학술대회 학술발표 논문집 제15권 제2호
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• pp.519-522
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• 2005

This paper presents a self-organizing scheme for multi-agent swarm systems based on coupled nonlinear oscillators (CNOs). In this scheme, unicycle robots self-organize to flock and arrange group formation through attractive and repulsive forces among themselves. It is also shown how localized distributed controls are utilized throughout group behaviors such as formation and migration. In the paper, the proposed formation ensures safe separation and good cohesion performance among the robots. Several examples show that the proposed method for group formation performs the group behaviors such as reference path following, obstacle avoidance and flocking, and the formation characteristics such as flexibility and scalability, effectively.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.1046-1051
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• 1991

For the conveyor tracking application of a robot manipulator, a new control scheme is presented. The presented scheme is divided into two stages : the upper one is the motion planning stage and the lower one is the motion control stage. In the upper stage, the nominal trajectory which tracks the part moving in a constant velocity, is planned considering the robot arm dynamics. On the other hand, in the lower level, the perturbed trajectory is generated to track the variation in the velocity of conveyor belt via sensory feedback and the perturbed arm dynamics. In both stages, the conveyor tracking problem is formulated as an optimal tracking problem, and the torque constraints of a robot manipulator are taken into account. Simulation results are then presented and discussed.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제5권3호
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• pp.222-229
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• 2005

This paper presents a self-organizing scheme for multi-agent swarm systems based on coupled nonlinear oscillators (CNOs). In this scheme, unicycle robots self-organize to flock and arrange group formation through attractive and repulsive forces among themselves. The main result is the maintenance of flexible and scalable formation. It is also shown how localized distributed controls are utilized throughout group behaviors such as formation and migration. In the paper, the proposed formation ensures safe separation and good cohesion performance among the robots. Several examples show that the proposed method for group formation performs the group behaviors such as reference path following, obstacle avoidance and flocking, and the formation characteristics such as flexibility and scalability, effectively.

• 한국태양에너지학회 논문집
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• 제39권4호
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• pp.79-91
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• 2019

The capacity credit (CC) is a key metric for mid- to long-term power system capacity planning. The purpose of this study is to estimate the CCs of domestic wind turbines. Based on hourly capacity factor (CF) data during the seven years from 2011 to 2017, the new so-called probabilistic CF scheme is introduced to effectively reflect the variability of CFs on CC estimation. The CCs are then estimated through the CF-based method and the ELCC (Effective Load Carrying Capability) method reflecting the probabilistic CF scheme, and the results are compared. The results show that the CC value 0.019 for domestic wind turbines proposed in the $8^{th}$ Basic Plan for Electricity Supply and Demand corresponds to the CC with a confidence level slightly lower than 95%.