In the manufacturing industry, dispatching systems play a crucial role in enhancing production efficiency and optimizing production volume. However, in dynamic production environments, conventional static dispatching methods struggle to adapt to various environmental conditions and constraints, leading to problems such as reduced production volume, delays, and resource wastage. Therefore, there is a need for dynamic dispatching methods that can quickly adapt to changes in the environment. In this study, we aim to develop an agent-based model that considers dynamic situations through interaction between agents. Additionally, we intend to utilize the Q-learning algorithm, which possesses the characteristics of temporal difference (TD) learning, to automatically update and adapt to dynamic situations. This means that Q-learning can effectively consider dynamic environments by sensitively responding to changes in the state space and selecting optimal dispatching rules accordingly. The state space includes information such as inventory and work-in-process levels, order fulfilment status, and machine status, which are used to select the optimal dispatching rules. Furthermore, we aim to minimize total tardiness and the number of setup changes using reinforcement learning. Finally, we will develop a dynamic dispatching system using Q-learning and compare its performance with conventional static dispatching methods.

수소는 다양한 신재생에너지 중 환경친화적인 에너지로 각광받고 있지만 농업에 적용된 사례는 드물다. 본 연구는 수소 연료전지 삼중 열병합 시스템을 온실에 적용하여 에너지를 절 약하고 온실가스를 줄이고자 한다. 이 시스템은 배출된 열을 회수하면서 수소로부터 난방, 냉각 및 전기를 생산할 수 있다. 수소 연료 전지 삼중 열 병합 시스템을 온실에 적용하기 위해 서는 온실의 냉난방 부하 분석이 필요하다. 이를 위해서는 온 실의 형태, 냉난방 시스템, 작물 등을 고려해야 한다. 따라서 본 연구에서는 건물 에너지 시뮬레이션(BES)을 활용하여 냉 난방 부하를 추정하고자 한다. 전주지역의 토마토를 재배하 는 반밀폐형 온실을 대상으로 2012년부터 2021년까지의 기 상데이터를 수집하여 분석했다. 온실 설계도를 참고하여 피 복재와 골조를 모델화하여 작물 에너지와 토양 에너지 교환을 실시했다. 건물 에너지 시뮬레이션의 유효성을 검증하기 위 해 작물의 유무에 의한 분석, 정적 에너지 및 동적 에너지 분석 을 실시했다. 또한 월별 최대 냉난방 부하 분석에 의해 평균 최 대 난방 용량 449,578kJ·h-1, 냉방 용량 431,187kJ·h-1이 산정 되었다.

Agrophotovoltaic (APV) system is an integrated system producing crops as well as solar energy. Because crop production underneath Photovoltaic (PV) modules requires delicate management of crops, smart farming equipment such as real-time remote monitoring sensors (e.g., thermometers, irradiance sensors, and soil moisture sensors) is installed in the APV system. This study aims at introducing a simulation-based decision support system (DSS) for smart farming in an APV system. The proposed DSS is devised to provide a mobile application service, satellite image processing, real-time data monitoring, and simulation-based performance estimation. Particularly, an agent-based simulation (ABS) is used to mimic functions of an APV system so that a data-driven function and digital twin environment are implemented in the proposed system. The ABS model is validated with field data collected from an actual APV system at the Jeollanamdo Agricultural Research and Extension Services in South Korea. As a result, farmers and engineers enable to efficiently produce solar energy without causing harmful impact on regular crop production underneath PV modules. In addition, the proposed system will contribute to enhancement of the digital twin technology in the field of agriculture.

The purpose of this study is to analyze the adequacy of production capacity of the assembly process system of mobile bath vehicle’s top box panel and process design through a simulation analysis. Towards this end, the layout of the facility designed with pre-verification job using a simulation modeling and an experiment, and facility, logistics process, and personnel input method were made into a simulation model, and the design system’s adequacy was evaluated through an experiment. To produce 120 mobile bath vehicles annually, it was analyzed that 14 general workers and seven skilled workers were adequate through the experiment. It was also identified that three painting process lines carried out through outsourcing were adequate. Production lead time was 201.7 hours on average and it was 230 hours maximum. To meet customer delivery service level of 95% within the deadline when establishing a customer order and vehicle delivery plan, it was analyzed that more than 215 hours of lead time is needed minimum. If the process cycle time is reduced to 85% upon system stabilization and skillfulness improvement, it was analyzed that annual output of 147 vehicles can be achieved without additional production line expansion.

가열 공정 중 고체와 액체 사이에 정확한 온도 분포를 식별하는 것은 다상식품 가공에서 매우 중요하다. 다상형태 의 고령친화 식품의 적절한 가공을 위해서는 불균일한 온도구배를 방지하며 신속하게 가공할 수 있는 새로운 열처리 방법의 개발이 필요하다. 연속 오믹히팅 스템은 모노 사인 펌프, IGBT 기반 전원 공급 장치, 오믹히팅 어플리케이터 로 구성되었다. 전원 공급 장치는 절연 게이트 바이폴라 트랜지스터 (IGBT), 로직 컨트롤러, 리액터 및 커패시터 뱅 크로 구성되었으며, 듀티 사이클(Duty cycle)과 주파수 (최대 20kHz)가 조절 가능함과 동시에 최대 50A 및 500V의 출 력이 가능하도록 설계되었다. 연속 저항 가열 시스템은 총 5 단계의 가열 섹션으로 이루어져 있으며, 각각의 가열섹 션을 구성하는 오믹 히팅 어플리케이터는 PTFE 튜브 양쪽 끝에 티타늄 관형 전극을 배치하여 제작되었다. 이 연구에 사용된 모델 식품은 시중에 판매되는 고령친화식품과 유사한 물리적 및 전기적 특성을 갖도록 모방되었다. COMSOL Multiphysics를 이용하여 가열 처리 중 오믹히팅 어플리케이터 내부에서 발생하는 다양한 현상을 시뮬레이션 하였다. 시뮬레이션은 400 ml/min 및 3수준의(200, 300, 400) Vrms가 적용되었으며 각 가열섹션에서 고체 및 액체의 온도구배 가 조사되었다. 200 Vrms의 최종 가열 단계에서 모델식품의 온도는 41℃로 확인되었으며, 각 가열 섹션을 통과할 때 마다 약 4℃씩 상승하였다. 300 Vrms의 최종 가열 단계에서는 67℃였으며, 각 가열 섹션을 통과할 때마다 약 9℃씩 상승하였다. 400 Vrms의 최종 가열 단계에서는 105℃로 확인되었으며, 각 가열 섹션을 통과할 때마다 약 14℃씩 상 승한 것으로 나타났다. 시뮬레이션 결과 모든 전압 조건에서 고체와 액체 사이의 불균일한 온도 구배는 해소된 것으 로 나타났으며, 기존 가열 방식에 비해 매우 높은 온도 상승률을 보여주었다. 본 연구에서는 다상 형태로 구성된 고 령친화식품을 가공하기 위하여 연속식 오믹히팅 시스템을 구성하였다. 수학적 모델링을 통한 Comsol Multiphysics 시 뮬레이션을 이용하여 액체 - 고체 사이의 온도구배 조사와 설계된 연속식 오믹히팅 시스템의 가열 공정의 거동 및 각 가열 단계별 오믹 어플리케이터 내부의 온도 분포를 분석하였다.

최근 환경규제가 강화됨에 따라 액화천연가스(Liquefied Natural Gas)를 이용하여 전력을 생산해내는 신규발전설비인 부유식 LNG 발전설비(floating LNG power plant)가 개발되고 있다. 부유식 LNG 발전설비는 운용 시 증발가스가 발생하고 이를 제거하거나 회수할 수 있는 시스템의 설계가 필요하다. 그러나 해양플랜트는 해상요건에 따라 설계가 상이하고, 부유식 LNG 발전설비의 설계 전 시행착오를 줄이기 위해 지속적으로 수정이 가능한 BOG 회수시스템 공정모사 모델이 필요하다. 따라서 본 연구에서는 상용공정시뮬레이션 프로그램을 통해 부유식 LNG 발전설비에 적합한 모델을 모델링하고자 냉매사용 유무에 따라 서로 다른 BOG(Boil-Off Gas) 회수시스템을 모델링하여 BOG의 회수율과 액화점을 비교 및 분석하였으며, 그 결과 질소냉매를 사용한 BOG 회수시스템 모델을 부유식 LNG 발전설비용 BOG 회수시스템 모델로 제안하고자 한다.

In this study, to improve the logistics flow of existing given chemical logistics warehouse, four logistics flow alternatives were proposed to minimize truck interference by building simulation model. The simulation model for chemical storage warehouse was built to evaluate system performance. Among the four new improved alternatives based on the basic model, the model with the same truck’s pathways and locations of facilities identified an increase in the number of interferences but a decrease in daily working hours as the number of resources in a particular facility increases. Therefore, the three groups were classified as ‘efficiency’, ‘complementary’, and ‘safety’ based on the daily working hours, and the ratio of trucks entering two types of logistics warehouse was set in consideration of future market fluctuations. For each of the six types, the optimal number of resources was selected as the number of resources in the facilities with the least number of interferences in the basic model and the evaluation measures and characteristics set in this study were compared and analyzed. As a result, the Alternative 4 model operating the underground roadway produced interference between 17.0% and 36.4% of the basic model, with 113.3% of the interior loadspace.

The concept of carsharing involves sharing a small number of reserved cars to be used individually by a larger number of people as required. This study examines the operating parameters of one-way carsharing systems in order to determine the appropriate operating conditions that minimizes the lost sales rate. Five operating parameters are tested in this study: the number of stations, the average number of vehicles per station, the rate of one-way trip, the average number of staffs per station, and the relocation policy. The performance of round-trip carsharing systems is also compared to that of one-way carsharing systems. A simulation model is developed and simulations are performed to determine the appropriate combination of operating parameter and levels. The simulation results show that the average number of vehicles per station is the most critical parameter. Other key findings obtained from this research are as follows. First, applying the appropriate relocation policy to one-way carsharing systems can allow more customers to rent vehicles than the traditional round-trip carsharing systems. Second, the appropriate relocation policy should be selected based on the average number of vehicles per station in order to minimize the lost sales rate. Third, the number of stations does not affect the lost sales rate. This study findings will provide tools to understand impact of the carsharing system parameters on the efficiency of the carsharing operations.

This study deals with the case study on the pallet quantity determination problem for the flexible manufacturing system producing 32 different types of aircraft wing ribs which are major structures of an aircraft wings. A Korean company has constructed the WFMS (wing rib flexible manufacturing system) that is composed of several automated equipments such as the 5-axis machining centers, the RGV (rail guided vehicles)s, the AS/RS (automated storage and retrieval system), the loading/unloading stations, and so on. Pallets play a critical role in the WFMS to maintain high system utilization and continuous work flow between 5-axis machining machines and automated material handling devices. The discrete event simulation method is used to evaluate the performance of the WFMS under various pallet mix alternatives for wing rib manufacturing processes. Four performance measures including system utilization, throughput, lead-time and work in process inventory level are investigated to determine the best pallet mix alternative. The best pallet mix identified by the simulation study is adopted in setting up and operating a real Korean aircraft parts manufacturing shop. By comparing the real WFMS’s performances with those of the simulation study, we discussed the cause of performance difference observed and the necessity of developing the CPS (cyber physical system).

본 연구는 어선전복경보시스템 개발을 위해 어선의 횡동요 특성을 파악하고 시간영역 횡동요 운동 시뮬레이션을 수행한다. 어 선전복경보시스템의 검증을 위해서는 전복 상황을 가정하여 시험을 수행하고 실제 어선 계측을 수행해야 하지만, 상황의 위험성으로 인 해 현실적으로 불가능하다. 또한 많은 전복사고의 경우 횡동요와 밀접한 연관이 있는 것으로 조사되었다. 이에 따라 어선전복경보시스템 의 핵심인 어선의 횡동요특성을 정확히 파악하여 시간영역 기반 횡동요 시뮬레이션을 수행하고 해당 정보를 통해 시스템에 탑재된 경보 시스템의 알고리즘을 검증한다. 주요내용으로 첫째, 횡동요 운동 특성을 운동 시험을 통해 계측하고 파악한다. 특히 어선과 같은 소형선 박의 경우 CFD 및 포텐셜 코드를 포함한 해석적인 방법으로 점성과 관련된 횡동요 해석이 어렵다. 이에 따라 횡동요 운동 모드에 초점을 맞추어 운동 시험을 수행하고 횡동요 RAO를 도출한다. 둘째, 횡동요 RAO를 이용하여 Wave Spectrum과의 조합으로 시간영역 운동 시뮬레 이션을 수행하고 전복 경보 알고리즘을 검증한다.

Using 3D based BIM(Building Information Modeling) enables a variety of construction simulations. The is no case to simulate BIM demonstration experiment on deeply immersed virtual reality environment in korea. This paper develops a multi screen based simulation system to enable 3D based immersed environment to diverse decision making and virtual construction simulation. In a developed simulation laboratory, we can carry out BIM drawing review, disaster evacuation simulation, constructability review on wild land and design urban planning using haptic device on 3-side space with 4K resolution . Also, It can review large amount of drawings without data conversion because of compatibility with BIM software.

BIM(building information modeling) has been actively applied to construction industries and to maximize its application through the life cycle of structure, various relevant technologies have been proposed. In particular, 4D sequencing management and 5D cost-related management were introduced as an improved version of the design review and interface control by 3D information design. On the other hand, the virtual construction using virtual construction equipment can sophisticatedly handle capacity, dynamic movement, collision boundaries of actual construction machines but it still stays at a low level in a technical sense. In this study, simulation systems based on BIM involving virtual construction equipment have been developed; then it is applied to the actual construction project to evaluate the safety and efficiency of construction equipments. It was confirmed that the simulation systems can be utilized to construct virtual construction site by using an effective 3D library of construction equipment and can plays a key role to secure construction safety and economic feasibility. Specifically, the simulation system are very useful for decision making by construction managers to select the optimum equipment and construction method with a better understanding for safety and cost-saving.