UAV (Unmanned Aerial Vehicle), the pilotless plane or drone, draws researchers’ attention at these days for its extended use to various area. The research was initiated for military use of the UAV, but the area of applicable field is extended to surveillance, communication, and even delivery for commercial use. As increasing the interest in UAV, the needs of research for operating the flying object which is not directly visible when it conducts a certain mission to remote place is obviously grown as much as developing high performance pilotless plane is required. One of the project supported by government is related to the use of UAV for logistics fields and controlling UAV to deliver the certain items to isolated or not-easy-to-access place is one of the important issues. At the initial stage of the project, the previous researches for controlling UAV need to be organized to understand current state of art in local researches. Thus, this study is one of the steps to develop the unmanned system for using in military or commercial. Specifically, we focused on reviewing the approaches of controlling UAV from origination to destination in previous in-country researches because the delivery involves the routing planning and the efficient and effective routing plan is critical to success to delivery mission using UAV. This routing plan includes the method to avoid the obstacles and reach the final destination without a crash. This research also present the classification and categorization of the papers and it could guide the researchers, who conduct researches and explore in comparable fields, to catch the current address of the research.
We consider a wafer lot transfer/release planning problem from semiconductor wafer fabrication facilities to probing facilities with the objective of minimizing the deviation of workload and total tardiness of customers’ orders. Due to the complexity of the considered problem, we propose a two-level hierarchical production planning method for the lot transfer problem between two parallel facilities to obtain an executable production plan and schedule. In the higher level, the solution for the reduced mathematical model with Lagrangian relaxation method can be regarded as a coarse good lot transfer/release plan with daily time bucket, and discrete-event simulation is performed to obtain detailed lot processing schedules at the machines with a priority- rule-based scheduling method and the lot transfer/release plan is evaluated in the lower level. To evaluate the performance of the suggested planning method, we provide computational tests on the problems obtained from a set of real data and additional test scenarios in which the several levels of variations are added in the customers’ demands. Results of computational tests showed that the proposed lot transfer/planning architecture generates executable plans within acceptable computational time in the real factories and the total tardiness of orders can be reduced more effectively by using more sophisticated lot transfer methods, such as considering the due date and ready times of lots associated the same order with the mathematical formulation. The proposed method may be implemented for the problem of job assignment in back-end process such as the assignment of chips to be tested from assembly facilities to final test facilities. Also, the proposed method can be improved by considering the sequence dependent setup in the probing facilities.
We focus on the fire scheduling problem (FSP), the problem of determining the sequence of targets to be fired at, for the objective of minimizing makespan to achieve tactical goals. In this paper, we assume that there are m available weapons to fire at n targets (> m) and the weapons are already allocated to targets. One weapon or multiple weapons can fire at one target and these fire operations should start simultaneously while the finish time of them may be different. We develop several dominance properties and a lower bound for the problem, and suggest a branch and bound algorithm implementing them. Also, In addition, heuristic algorithms that can be used for obtaining an initial upper bound in the B&B algorithm and for obtaining good solutions in a short time were developed. Computational experiments are performed on randomly generated test problems and results show that the suggested algorithm solves problems of a medium size in a reasonable amount of computation time. The proposed lower bound, the dominance properties, and the heuristics for upper bound are tested in B&B respectively, and the result showed that lower bound is effective to fathoming nodes and the dominance properties and heuristics also worked well. Also, it is showed that the CPU time required by this algorithm increases rapidly as the problem size increases. Therefore, the suggested B&B algorithm would be limited to solve large size problems. However, the employed heuristic algorithms can be effectively used in the B&B algorithm and can give good solutions for large problems within a few seconds.
Because land based aquaculture is restricted by high investment per rearing volume and control cost, good management planning is important in Land-based aquaculture system case. In this paper master production planning was made to decide the number of rearing, production schedule and efficient allocation of water resources considering biological and economic condition. The purpose of this article is to build the mathematical decision making model that finds the value of decision variable to maximize profit under the constraints. Stocking and harvesting decisions that are made by master production planning are affected by the price system, feed cost, labour cost, power cost and investment cost. To solve the proposed mathematical model, heuristic search algorithm is proposed. The model Input variables are (1) the fish price (2) the fish growth rate (3) critical standing corp (4) labour cost (5) power cost (6) feed coefficient (7) fixed cost. The model outputs are (1) number of rearing fish (2) sales price (3) efficient allocation of water pool.
This study aimed to evaluate the effectiveness of closed season policy using an integer linear programming, targeting the large purse seine fishery in Korea. In the analysis, based on Cheng and Townsend(1993), fishing effort (fishing days by month) was assumed to be distributed for profit maximization of vessels and catch of immature fish was estimated. The analytical results showed that the effects of closed season policy would vary in accordance with the monthly closures in terms of fishing profits and catch of immature fish. A closed season policy by month had different effects on fishing profits and catch of immature fish by species. It implies the importance of considering seasonal changes of fish species when limiting fishing efforts with the closed season policy.
In this paper, we present a multi-period 0-1 knapsack problem which has the cardinality constraints. Theoretically, the presented problem can be regarded as an extension of the multi-period 0-1 knapsack problem. In the multi-period 0-1 knapsack problem, there are n jobs to be performed during m periods. Each job has the execution time and its completion gives profit. All the n jobs are partitioned into m periods, and the jobs belong to i-th period may be performed not later than in the i-th period, i = 1, ⋯, m. The total production time for periods from 1 to i is given by bi for each i = 1, ⋯, m, and the objective is to maximize the total profit. In the extended problem, we can select a specified number of jobs from each of periods associated with the corresponding cardinality constraints. As the extended problem is NP-hard, the branch and bound method is preferable to solve it, and therefore it is important to have efficient procedures for solving its linear programming relaxed problem. So we intensively explore the LP relaxed problem and suggest a polynomial time algorithm. We first decompose the LP relaxed problem into m subproblems associated with each cardinality constraints. Then we identify some new properties based on the parametric analysis. Finally by exploiting the special structure of the LP relaxed problem, we develop an efficient algorithm for the LP relaxed problem. The developed algorithm has a worst case computational complexity of order max[O(n2log n), O(mn2)], where m is the number of periods and n is the total number of jobs. We illustrate a numerical example.
초가속수명시험(HALT:Highly Accelerated Life Test)은 온도변화와 진동을 통해 부품초기 고 장을 빠르게 찾아 개선함으로써 제품의 신뢰성을 향상시킨다. 이에 따라 기업들은 초가속수명시 험에 집중하게 되었고 장비의 수요와 가동률이 증가하고 있다. 그러나 초가속수명시험 장비는 대부분 해외 장비에 의존하고 있어 고장이 발생한 경우 유지보수에 대한 비용이 높고 보전까지 의 시간 또한 길다. 뿐만 아니라 장비에 대한 적절한 보전절차가 없어 비용과 시간의 손실이 발 생되는 실정이다. 본 논문에서는 국산화 개발중인 초가속수명시험 장비에 고장유형과 원인에 따른 계획보전 활 동을 진행 할 수 있도록, FMEA(Failure Modes and Effects Analysis)를 사용하여 계획보전절 차를 제시하였다.
최신의 방사선치료 기법 중의 하나인 체적변조회전치료의 경우 치료 시 방사선은 회전하면서 연속조사를 실시하는 반면 치료계획상에서는 1도 간격의 고정조사형태로 계획되게 된다. 이에 본 연구에서는 체적변조회전치료계획의 정확성을 평가하고자 하 였다. 연속조사에 대한 치료계획이 불가능하므로 3구간에 대해 0.2도 간격, 0.5도 간격, 1.0도 간격, 2.0도 간격으로 치료계획을 실시하여 6개의 용적에 대해 처방선량의 50% 와 70% 용적에 대한 V50과 V70의 평가지표를 비교하였다. 그리고 평가지표 별 용적 에 대한 선속간격 그래프를 통해 연속조사에 대한 값을 외삽하여 추정하였다. 그리고 외삽된 연속조사의 값과 1도간격인 치료계획의 값을 비교하여 오차값을 획득하였다. 그 결과 V50에서는 최대 9.46%의 차이를 보였으며, V70의 경우 최대 25%의 차이를 보였다. 이를 통해 체적변조회전치료계획의 경우 선량의 부정확성을 인지하면서 치료 계획을 실시하여야 하며, 치료계획 컴퓨터의 개발 시 1도 간격이 아닌 본 연구의 결과 에서 처럼 0.5도 간격으로 재설정하여야 할 것이다. 물론, 간격이 좁아지면 계산속도가 느려지므로, 2단계에 걸쳐 계산하는 시스템의 도입도 고려해보아야 할 것이다.해야 할 것이다.
This paper deals with the production plan for the foaming process, the core part of the refrigerator manufacturing process. In accordance with this change, the refrigerator manufacturing process has also been converted into the mixed-model production system and it is necessary to optimize the production release pattern for the foaming process. The pattern optimization is to create a mixed-model combination which can minimize the number of setup operations and maintain mixed-model production. The existing method is a simple heuristic that depends on the demand priority. Its disadvantages are low mixed-model configuration rate and high setup frequency. Therefore, demand partitioning occurs frequently. In this study, we introduce the tolerance concept and propose a new pattern optimization algorithm based the large neighborhood search (LNS). The proposed algorithm was applied to a refrigerator plant and it was found that mixed-model configuration rate can be improved without demand partitioning.
PURPOSES : Traffic accidents and damage due to speeding should be recognized as a problem which harms society and the economy as well as the parties to the accidents. It is time to seek more detailed and concrete customized alternatives than the existing policies for the prevention of traffic accidents.
METHODS: In this study, we identified the characteristics driver behavior and psychological factors that lead to speeding, and a study was carried out to verify the causality models developed from the factors we identified.
RESULTS : Driving behavior variables have a significant effect on speeding behaviors in order of Lapse, Violation, and Mistake. And the violation which is defined as intentional violation showed the result which supports the research hypothesis as it has the significant effect on speeding intention and behaviors.
CONCLUSIONS: The result of this study can be utilized to develop educational problems concerning speeding and previous response with the main objective of eliminating speeding driver behavior.
수출입식물의 검역 중 발견되는 병해충의 사멸을 위하여 소독처리를 실시하고, 이 때 주로 사용하는 약제가 1989년 몬트리올 의정서에 오존층파괴물질로 지정된 메틸브로마이드라는 고독성 훈증제이다. 농림축산검역본부에서는 2006년부터 메틸브로마이드 대체를 위하여 저독성이면서 친환경적인 소독기술 개발을 추진하여 2014년까지 바나나, 오렌지 등 5개 품목에 대한 에틸포메이트 훈증제 소독기술, 장미, 백합 등 4개 품목에 대한 포스핀 훈증제의 소독기술을 개발하였다. 그 결과 메틸브로마이드 사용량을 2011년 559톤에서 2014년 458톤으로 약 100톤 감축하고, 메틸브로마이드로만 소독되던 수입 바나나 소독물량의 85%를 에틸포메이트 훈증제로 대체하여 바나나 약해 피해 약 1,650억원(연간)을 경감하는 효과를 거두었다. 그러나 아직 메틸브로마이드만큼 광범위한 식물에 적용되는 약제가 개발되지 않았기에 앞으로 검역본부는 예산과 인력을 집중적으로 투자하여 기술개발을 촉진하고 소독기술을 발전시킬 계획이다. 우선 2018년까지 메틸브로마이드를 대체할 28개 주요품목을 설정하여 소독기술 개발을 완료할 계획이다. 이를 위하여 검역본부, 학계, 산업계가 공동으로 참여하는 연구 사업을 적극적으로 추진하여 시너지를 극대화할 계획이다. 다음으로 효율적이고 경제적인 소독방법을 개발할 계획이다. 에틸포메이트는 침투력이 약하고 비싸며 포스핀 훈증제는 소독시간이 긴 단점이 있기에 사용에 한계가 있다. 따라서 약제의 생산단가를 낮추면서 효율성과 실용성을 높이는 소독방법을 개발할 계획이다. 끝으로 외부에서 수행한 연구결과를 평가하고 설정할 수 있는 소독처리기준 평가시스템을 구축하고 운영하는 한편, 인력, 시설, 장비 등 소독 연구 인프라를 확충할 계획이다. 외래병해충 유입방지, 자연환경 보호, 안전사고 예방을 위하여 메틸브로마이드 대체 소독기술개발 사업을 시작한 지가 벌써 10년이 되었다. 이제 이를 가속화할 수 있도록 제도적인 뒷받침과 함께 우리 사회와 국민 모두의 지속적인 관심과 응원이 필요할 때이다.
The objective of this study is to analyze the investment adequacy of the projects implemented according to the master plan on sewerage rehabilitation at Seoul. The planned and actually implemented ratio of invested money on sewage treatment plants (STPs) to sewers were compared in two temporal periods. Though the planned ratio of investment on STPs to sewers was 50:50 (in 2009-2020) , the actual implemented ratio in 2009-2013 was 34:66. Until 2020, the greater investment ratio on STPs to sewers should be made considering the necessity of coping with stricter legal compliance on advanced treatment, stormwater treatment and so on. The priority of the planned and partially implemented projects among four STPs and at each STP was evaluated. Considering only the performance indicator of reduced load of BOD, T-N, T-P per the capacity of each STP facility, the performance among four STPs was shown as Jung-Rang>Tan-Cheon>Seo-Nam>Nan-Ji. The reverse order of the performance results in the past may be considered for future investment priority, but the efficiency of operation implemented at each STP, deteriorated status of each STP, investment in the past and so forth should also be considered. As for the priority of projects conducted within each STP, projects related to legal compliance (such as advanced tertiary treatment, stormwater treatment, etc.) have highest priority. Odor-related project and inhabitant-friendly facility related projects (such as building park on STPs, etc.) has lower priority than water quality related projects but interactivity with end-users of sewerage should also be important.
진안의 대표적 관광지인 마이산 북부는 여러 개발 사업이 이루어지고 있으나, 종합적 개발계획이 필 요하고, 특히 기존 주차장부지와 상가지구를 대상으로 새로운 계획을 수립해야 할 시점이다. 본 연구에서는, 먼저, 마이산 북부지구를 대상으로 개발 관련 문헌조사와 현장조사를 통하여 현황 분석을 하였고, 개발 잠재력 및 장단점분석을 하였다. 이를 바탕으로, 마이산 북부지구의 전체적인 공간구성 개선방향에 대하여 제시하였고, 세부적으로 마이산 북부지구 중 이전 계획이 수립된 북부주차장 및 상가지구에 대 한 계획안으로 생태복원공원계획과 생활사전시관 및 명인명품전시관을 제시하였다.
진안의 대표적 관광지인 마이산 북부는 여러 개발 사업이 이루어지고 있으나, 종합적 개발계획이 필 요하고, 특히 기존 주차장부지와 상가지구를 대상으로 새로운 계획을 수립해야 할 시점이다. 본 연구에서는, 먼저, 마이산 북부지구를 대상으로 개발 관련 문헌조사와 현장조사를 통하여 현황 분석을 하였고, 개발 잠재력 및 장단점분석을 하였다. 이를 바탕으로, 마이산 북부지구의 전체적인 공간구성 개선방향에 대하여 제시하였고, 세부적으로 마이산 북부지구 중 이전 계획이 수립된 북부주차장 및 상가지구에 대 한 계획안으로 생태복원공원계획과 생활사전시관 및 명인명품전시관을 제시하였다.