제강.연주 공장 설계와 운영을 위한 시뮬레이터

최성훈,Choi, Seong-Hoon 한국시뮬레이션학회 2011 한국시뮬레이션학회 논문지 Vol.20 No.2

치열한 경쟁과 원자재 가격 급등은 시행착오를 최소화 하면서 제철소를 최적으로 설계하여 운영할 것을 한층 더 강력하게 요구하고 있다. 컴퓨터 시뮬레이션은 이 요구에 부합되는 방법론을 제공할 수 있다. 본 논문의 목적은 제강 연주 공장의 설계와 운영을 지원하기 위한 시뮬레이터를 제안하는 것이다. 본 연구에서 제안하는 시뮬레이터는 유지보수와 확장에 용이하도록 널리 알려진 Arena로 개발되었으며 사용의 편의성을 위하여 엑셀 기반으로 입출력 인터페이스를 설계하였다. 또한 운반 대차와 천정 크레인으로 구성되는 복잡한 운반 모듈을 포함하여 모델의 정확도를 높였다. 시뮬레이터는 생산량 분석과 물류 분석을 통하여 제강 연주 공장 설계안의 적정성을 평가하는데 유용하게 사용될 수 있다. 그리고 다양한 상황별로 최적의 제품 조합을 도출하는데 적용될 수 있으며, 공정별 설비별로 작업을 배정하는 조업 운영 패턴을 평가하고 정확도를 향상시키는 도구로써 활용이 가능하다. Stiff competition and skyrocketing prices of raw materials are increasingly demanding the optimal design and operation of iron and steel mills minimizing trial and error. Computer simulation can provide the methodology in accordance with requirements. The purpose of this paper is to suggest a simulator for the design and operation of the steelmaking and continuous casting mill. The simulator was developed using Arena, popular simulation software and input and output interface based on MS Excel. It allows easy access for the maintenance and extension of the model. One of distinct features of the proposed simulator is the inclusion of complex transportation modules composed of transfer cars and overhead cranes. The simulator can be used for evaluating various alternative designs of a projected mill via throughput analysis and material flow analysis. Also, one can utilize it effectively to search for the best product mix suitable for many types of situations. It could be an invaluable tool evaluating the performance of operation patterns and improving the accuracy.

Halcyon^TM 선형가속기 6MV-FFF 에너지의 표재 선량에 대한 고찰: Phantom Study

최성훈,엄기천,유순미,박제완,송흥권,윤인하,Choi, Seong Hoon,Um, Ki Cheon,Yoo, Soon Mi,Park, Je Wan,Song, Heung Kwon,Yoon, In Ha 대한방사선치료학회 2020 대한방사선치료학회지 Vol.32 No.-

목 적: 본 연구는 HalcyonTM과 TrueBeamTM에서 사용하는 6MV-FFF(Flattening Filter Free) 에너지를 이용하여 전산화치료계획시스템(Treatment Planning System, TPS)에서 계산된 선량과 광자극형광선량계(Optically Stimulated Luminescence Dosimeter, OSLD)로 측정된 표재 선량(Superficial dose)을 비교하고자 한다. 재료 및 방법: 팬텀연구를 위해 인체모형 팬텀(Human Phantom)의 CT 영상을 이용하여 치료계획시스템에서 성문암(Glottic cancer)과 유사한 치료계획용적(Planning Target Volume, PTV)과 두경부위의 등 중심점(Iso-center) 위치에 측정을 위한 Point(M), Point(R), Point(L)의 구조물을 설정하고 체표윤곽(Body contour)에 5mm Bolus를 적용하였다. 그 후 전산화치료계획은 HalcyonTM과 TrueBeamTM의 6MV-FFF 에너지를 이용하여 정적(Static) 세기변조방사선치료(Intensity Modulated Radiation Therapy, IMRT)와 용적변조회전치료(Volumetric Modulated Arc Therapy, VMAT)계획을 각각 수립하였다. 전산화치료계획과 동일하게 재현하기 위해 OSLD를 등 중심점에 위치시키고 5mm Bolus를 적용하여 선량 전달 후 오차율을 비교하였다. 결 과: 인체모형 팬텀을 사용한 실험 결과 HalcyonTM의 전산화치료계획시스템에서의 점 선량과 OSLD를 이용한 선량 측정의 오차율의 절댓값의 평균은 VMAT, IMRT 각각 1.7±1.2%, 4.0±2.8%로 확인되었으며, TrueBeamTM의 오차율의 절댓값의 평균은 VMAT, IMRT 각각 2.4±0.4%, 8.6±1.8%로 확인되었다. 결 론: 실험결과 HalcyonTM을 기준으로 TrueBeamTM에서 VMAT과 IMRT 각각 2.4배, 3.6배 더 큰 오차가 발생하는 것을 확인할 수 있었다. 따라서 본 연구의 결과를 토대로 표재 선량에 대한 정확한 선량평가가 이루어져야 하는 경우, TrueBeamTM보다 HalcyonTM에서 정확한 선량 평가가 이루어질 수 있을 것으로 사료된다. Purpose: The aims of this study were to compare the superficial dose with Optically Stimulated Luminescence Dosimeter(OSLD) measurement and Treatment Planning System(TPS) calculation for 6MV-Flattening Filter Free(FFF) energy using HalcyonTM and TrueBeamTM. Materials and methods: Phantom study was performed using the CT images of human phantom. In the treatment planning system, the Planning Target Volume(PTV) was contoured which is similar to Glottic cancer. Furthermore, Point(M), Point(R), and Point(L) were contoured at the iso-center of head and neck region and 5mm bolus was applied to the body contour. Each treatment plans using 6MV-FFF energy from HalcyonTM and TrueBeamTM with static Intensity Modulated Radiation Therapy(IMRT) and Volumetric Modulated Arc Therapy(VMAT) were established with eclipse. To reproduce the same position as the TPS, OSLDs were placed at the iso-center point and 5mm bolus was applied to compare the error rate after the dose delivery. Result: The results of the study using human phantom are as follows. In case of HalcyonTM, the mean absolute error rates of the point dose using the treatment planning system and the dose measured by OSLD were 1.7%±1.2% for VMAT and 4.0±2.8% for IMRT. Also TrueBeamTM was identified as 2.4±0.4% and 8.6±1.8% respectively for VMAT and IMRT. Conclusion: Through the results of this study, TrueBeamTM confirmed that the average error rate was 2.4 times higher for VMAT and 3.6 times higher for IMRT than HalcyonTM. Therefore, based on the results of this study, If we need a more accurate dose assessment for the superficial dose, It is expected that using HalcyonTM would be better than TrueBeamTM.

Arena를 이용한 조직에서의 사회연결망 시뮬레이터 개발에 관한 연구

최성훈(Seong-Hoon Choi) 한국산업경영시스템학회 2012 한국산업경영시스템학회지 Vol.35 No.3

This thesis proposes a new social network simulator, which can be used for the social network analysis (SNA). It is composed of three modules; initialization, network evolution, and output generation. For the network evolution module, we suggest a modified JGN (MJGN) based on JGN, the network evolution model developed by Jin, Girvan, and Newman. Arena, one of the most popular simulation tools, was used to model the agent based social network simulator. Lastly, some test results were presented to show the value of the proposed simulator when one performs SNA at the longitudinal point of view.

Optimizing Assembly Line Balancing Problems with Soft Constraints

Seong-Hoon Choi(최성훈),Geun-Cheol Lee(이근철) 한국산업경영시스템학회 2018 한국산업경영시스템학회지 Vol.41 No.2

In this study, we consider the assembly line balancing (ALB) problem which is known as an very important decision dealing with the optimal design of assembly lines. We consider ALB problems with soft constraints which are expected to be fulfilled, however they are not necessarily to be satisfied always and they are difficult to be presented in exact quantitative forms. In previous studies, most researches have dealt with hard constraints which should be satisfied at all time in ALB problems. In this study, we modify the mixed integer programming model of the problem introduced in the existing study where the problem was first considered. Based on the modified model, we propose a new algorithm using the genetic algorithm (GA). In the algorithm, new features like, a mixed initial population selection method composed of the random selection method and the elite solutions of the simple ALB problem, a fitness evaluation method based on achievement ratio are applied. In addition, we select the genetic operators and parameters which are appropriate for the soft assignment constraints through the preliminary tests. From the results of the computational experiments, it is shown that the proposed algorithm generated the solutions with the high achievement ratio of the soft constraints.

심리동사 보문구조의 의미에 관한 연구

최성훈 ( Seong Hoon Choi ) 한국현대언어학회 2015 언어연구 Vol.30 No.4

The purpose of this paper is to explore the different readings of the argument structure in psych verbs in Korean. Some scalable predicate of psych verbs can be interpreted as an event or a fact reading depending on the argument forms such as derived noun phrase or gerund in English. In addition to this, the argument form, V+n ji/ga, of the psych verbs in Korean can be interpreted as fact reading, and V+ tense + ji/ga form as event reading. Finally we managed to present the meanings of the fact and event of the argument form of psych verb in Korean within the revised form of subatomic semantics. However, the argument forms of the psych verbs have various structures so that it is important to classify the argument forms and to figure out the meaning of the forms. (Songwon University)

작업관리를 위한 엑셀 기반의 간이 수행도 평가 훈련 툴 개발

최성훈(Seong-Hoon Choi) 한국산업경영시스템학회 2012 한국산업경영시스템학회지 Vol.35 No.2

The purpose of this thesis is to develop a performance rating training tool for the time and motion study. It is widely recognized that rating training tools based on films were made several decades ago and introduced to Korea. However, to the best of our knowledge, those films are not used for rating training in Korea any more. Furthermore, although rating is still important method for the efficient operational management study, it is briefly mentioned without any training or exercise. In this paper, we propose a simple rating training tool based on Excel with VBA. The mottoes of our development are the ease of acquisition and trainees’ motivation. Test results show that trainees can obtain the concept of rating and the ability of accurate and consistent rating as they play a computer game sitting in front of the personal computer.

일반 조립 라인 편성 문제를 위한 정수계획 모형

최성훈 ( Seong Hoon Choi ) 한국생산성학회 2011 生産性論集 Vol.25 No.1

This paper considers the design problem of assembly lines which are flow oriented production system suitable for mass production. Sine the installation of an assembly line is a midlong-term decision and usually requires large capital investments, it is important that such a system is optimally designed. The simple assembly line balancing problem(SALBP) is allocating tasks to workstations under the cycle time(sum of task times) constraint of each workstation and precedence constraints between tasks. In addition to the basic constraints of SALBP, the generalized assembly line balancing problem(GALBP) considers assignment restrictions such as incompatibilities between tasks, resource(operator) related workstation restriction, etc. The purpose of this paper is to introduce a new integer programming model for GABLP. We propose mild constraints and task-task/task-workstation relationship matrices. these are useful for presenting and solving GALBP as more realistic form.

휴대 인터넷 시스템에서의 패킷 스케줄링 방법 평가를 위한 시뮬레이터 개발

최성훈(Choi, Seong-Hoon) 한국산학기술학회 2006 한국산학기술학회논문지 Vol.7 No.6

언제 어디서나 초고속으로 무선인터넷 사용을 목표로 하는 휴대인터넷 시스템이 곧 상용화될 예정이다. 휴대 인터넷 시스템은 서로 다른 특성을 가지고 있는 UGS, rtPS, ooPS, BE 서비스들을 동시에 제공하므로 QoS를 고려한 효율적인 스케줄링 기법을 필요로 한다. 본 연구에서는 다양한 파라미터 값들에 대한 스케줄링 기법의 성능을 평가할 수 있는 시뮬레이터를 개발하였다. 모델을 변경하지 않고 시스템을 구성하는 다%탤 특성치들을 쉽게 변경하면서 시뮬레이션을 실시할 수 있도록 일반화 한 것이 제안 시뮬레이터의 장점이다. HPI(High-speed Portable Internet) system is going to be commercialized before long. Efficient scheduling mechanisms for UGS, rtPS, nrtl’S and BE, which are service types of the HPI, are necessary to increase the utilization of wireless channels under the different QoS requirements. In this paper, we develop a simulator which can be used to evaluate the performance of scheduling mechanisms. The advantage of the proposed simulator is that one can simulate diverse situations not changing the simulation model but just setting various parameters.

휴대 인터넷 시스템에서의 패킷 스케줄링 알고리즘 연구

최성훈(Seong-Hoon Choi) 한국산업경영시스템학회 2007 한국산업경영시스템학회지 Vol.30 No.1

  HPI (High-speed Portable Internet) system which provides high speed internet services is going to be commercialized soon. Since HPI provides simultaneously four different service types such as UGS (Unsolicited Grant Service), rtPS (real time Polling Service), nrtPS (non-real time Polling Service), and BE (Best Effort) under different QoS (Quality of Service) requirements and limited wireless channel resources, efficient packet scheduling mechanisms are necessary to increase the utilization of channels as well as to satisfy the various QoS requirements. This study regards the traffic data to be served as time series and proposes a new packet scheduling algorithm based on the nonparametric statistical test. The performance of the newly proposed algorithm is evaluated through the simulation analysis using a simulator that can evaluate the performance of packet scheduling mechanisms under various values of system parameters and measures such as packet delay time, data transmission rate, number of loss packets, and channel utilization.

ICT연계형 수상태양광 시스템 기반의 NET-ZERO 에너지 관리 알고리즘

최성훈(Seong-Hun Choi),박동환(Dong-Hwan Park),최현준(Hyun-Jun Choi),안정훈(Jung-Hoon Ahn) 전력전자학회 2023 전력전자학술대회 논문집 Vol.2023 No.7