• Journal of Electrical Engineering and Technology
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• 제12권2호
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• pp.918-925
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• 2017

This paper presents a path planning problem for multi-robot system in the environment with dynamic obstacles. In order to guide the robots move along a collision-free path efficiently and reach the goal position quickly, a navigation method based on fuzzy logic controllers has been developed by using proximity sensors. There are two kinds of fuzzy controllers developed in this work, one is used for obstacle avoidance and the other is used for orientation to the target. Both static and dynamic obstacles are included in the environment and the dynamic obstacles are defined with no type of restriction of direction and velocity. Here, the environment is unknown for all the robots and the robots should detect the surrounding information only by the sensors installed on their bodies. The simulation results show that the proposed method has a positive effectiveness for the path planning problem.

• 조명전기설비학회논문지
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• 제13권2호
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• pp.32-38
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• 1999

운송설비용 자율 주행 운반체는 인간의 지도없이 주어진 환경 내에서 장애물과 충돌을 회피하며 효율적으로 목표지점까지 주행할 수 있는 최적의 이동 경로를 생성해야 한다. 본 논문에서는 장애물과 충돌을 회피하는 전역 및 지역경로를 유전알고리즘을 이용하여 계획하였다. 본 논문에서는 제안한 운송설비용 자율 주행 운반체의 충돌회피 알고리즘은 전통적인 충돌회피 알고리즘에 비해 능률적임을 모의 실험을 통해 확인하였다.

• Journal of Electrical Engineering and information Science
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• 제2권3호
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• pp.51-60
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• 1997

A practically applicable collision free trajectory planning technique for tow robot systems is proposed. The robot trajectories considered in this work are composed of many segments, an at the intersection points between segments robots stop to assemble, weld, ordo other jobs by the attached a end-effectors. The proposed method is based on the Planning-Coordination Decomposition where planning is to find a trajectory of each robot independently according to their tasks and coordination is to find a velocity modification profile to avoid collision with each other. To fully utilize the independently planned trajectories and to ensure no geometrical path deviation after coordination, we develop a simple technique added the minimal delay time to avoid collision just before moving along path segments. We determine the least delay time by the graphical method in the Coordination space where collisions and coordinations are easily visualized. We classify all possible cases into 3 group and derive the optimal solution for each group.

• 한국조명전기설비학회지:조명전기설비
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• 제13권2호
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• pp.164-164
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• 1999

An autonomous mobile vehicle for transport system must plan optimal path in work environment without human supervision and obstacle collision. This is to reach a destination without getting lost. In this paper, a genetic algorithm for global and local path planning and collision avoidance is proposed. The genetic algorithm searches for a path in the entire and continuous free space and unifies global path planning and local path planning. The simulation shows the proposed method is an efficient and effective method when compared with the traditional collision avoidance algorithms.

• 한국국방경영분석학회지
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• 제16권2호
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• pp.151-167
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• 1990

Considerable research has concentrated on medium-range production planning model in that it can contain long and short-term decision making in contents. Since medium-range production planning deals in situations with setup time or/and costs, solution methodology is classified by (1) optimization method using a sort of integer programming approach and network formulation (2) heuristic method offering an computationally easy, approximate solution. But, solution methodology is different in type of demand generation, existence of capacity and dependant demand. Therefore this paper reviewed the medium range production planning according to above mentioned three factors, and suggested for further work direction.

• Journal of Construction Engineering and Project Management
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• 제2권3호
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• pp.40-47
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• 2012

Construction management is essential for a achieving any pre-determined objective. It is however seen that in spite of construction management, majority of the project do not keep up their original time schedule and their completion cost is also higher as compared with the estimated cost The main reason for overrun in time and cost is that the planning at the outset of the project was not adequate or method of planning was not a refined one. In this research work, I showed the overall conditions of construction work and management in Sylhet city of Bangladesh and found many drawbacks in the construction management after completing my research. I found several factors affecting proper construction management and I have provided brief results. I have also provided some recommendations after my research work.

• 패션비즈니스
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• 제19권4호
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• pp.183-199
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• 2015

This study aimed to systematize the apparel vendor work processes and provide useful information to future employees of clothing export units by analyzing the processes of vendors' manufacturing tasks. A survey of 20 apparel vendors servicing mainly U.S. buyers was conducted on employees of overseas business departments working for more than five years. buyers. Based on the results, vendors mainly manufactured cut-and-sew knit products. Regarding the production method, OEM was used more frequently than ODM. Fourteen (70%) companies used the ODM method. This suggests that vendors are expanding their production method from OEM to ODM. In order to summarize the work of each business based on the clothing production process research results, buyers were in charge of planning products and the vendors were in charge of sampling. Production of materials and the approval of material tests were out sourced. Overseas factories of vendors were in charge of bulk (mass) production and garment finishing, as well as packaging and shipping the completed products. Even though the vendors' head offices do not directly produce clothes, they play a pivotal role in ensuring planning and management progress in clothing production. As buyers prefer direct contracts for cost reduction, the vendor additionally performs the role of an agent. Also, with the increase in ODM production ratio, the work area of the vendor is expanding. If Korean clothing exporters improve their global competitiveness by investing in the R&D of materials and design to enhance the ODM method, the development of Korea's clothing and export industry will benefit significantly.

• 한국건설관리학회논문집
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• 제23권4호
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• pp.65-77
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• 2022

공정관리는 건설 프로젝트에서 가장 중요한 프로젝트 성공 요인 중 하나이다. 그러나, 기존의 공정계획 기법은 건설 프로젝트에서 상당한 수작업과 관리자의 판단이 필요하기 때문에 신속한 공정계획과 운영에 많은 어려움이 있다. 본 연구는 공정계획을 자동화하고 시각화하기 위한 새로운 공정계획 기법과 알고리즘을 제안하는 것을 목적으로 하며, 이를 가산 그리드 공정계획 기법(CSM)이라고 한다. 이 기법은 시각화된 도구를 통해 작업 범위를 정의하면 각 작업의 생산성과 작업 가능 조건에 따라 일정계획이 자동으로 생성된다. 날짜별 작업의 위치를 그리드 기반 접근방식으로 시각화할 수 있다. 또한 작업 일정은 진행 상황에 따라 자동으로 갱신할 수 있다. 제안된 기법의 산업적 활용 가능성을 건설프로젝트의 샘플 데이터를 가지고 사례 연구를 통해 검증하였다. 본 연구는 공정관리 프로세스를 자동화하여 건설 산업에 기여할 수 있을 깃으로 기대한다.

• 한국건설관리학회논문집
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• 제6권6호
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• pp.90-97
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• 2005

현대의 건축공사는 고층화 추세에 따라 반복공정의 수가 증가하여 작업 연속성에 대한 계획 및 공사관리가 중요하게 인식되고 있다. 특히, 많은 반복공정이 동시에 수행되는 마감공사는 작업흐름의 관리에 따라 전체공사에 큰 영향을 미치므로 작업 연속성에 대한 계획이 필요하다. 마감공사의 합리적 운영을 위해 작업연속성을 확보하여 목표공기를 달성하는 기법인 택트 공정관리에서는 택트타임을 설정하여 반복작업의 작업편차를 일정하게 하여 공사계획을 수립한다. 그러나, 기존 택트공정 관리와 관련된 연구는 작업구역분할, 작업일보, 택트 공정관리 프로세스 등을 수행하였지만 작업 연속성 확보를 위한 택트타임에 대한 연구는 충분히 수행되어 있지 않은 실정이다. 따라서 본 연구에서는 3점추정견적 방법에 의한 택트타임의 설정방법과 작업기간 조정절차를 제시하여 택트타임 기반의 공정계획수립 방법을 제시하였으며, 이와 같은 방법에 의한 택트공정 계획 수립을 통해 목표공기가 지연되지 않음을 입증하였다.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1996년도 춘계공동학술대회논문집; 공군사관학교, 청주; 26-27 Apr. 1996
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• pp.709-712
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• 1996

Generating a project network of a specific construction project is very time consuming and difficult task in the field. To effectiviely automate and support the planning process, we design a case-based project planning expert system inspired by the fact a human expert project planner uses previous cases for planning a new project. A construction project case consist of its specific characteristics and the corresponding project network (i.e. project plan). Using frame based representation. we represent the project features affecting the progress network and the entities composing the project plan such as the buildings, construction methods, WBS (work breakdown structure), activities, and resources. The project planning process runs through most similar case retrieval, case adaptation, and user requirement satisfaction. We represent the construction domain knowledge for each procedure using constraints and rules. We develop the methodology for constraint-based case adaption. Case adaptation process mainly consist of activity generation/deletion and predecence constraint satisfaction, for which we develop the dynamic constraint generation method and connect user-level requirement representation the system-level network modification knowledge. The methodology is being applied to the prototype for apartment construction project planning.