• 산업경영시스템학회지
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• 제19권40호
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• pp.203-217
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• 1996

This thesis describes a quantitative decision-making of production planning system. A mathmatical model of Linear Programming is used set up a production scheuling under the assumption. As the emphasis is laid on the applicability of the developed model, the linrar programming is applied to establish the production schedule for "F" furniture company which produces kitchin cabinet and OA furniture, The optimal solution is obtained by using the LP package, QBS. By the solution reduced to 14% of work force compared with the real data during all of the planning horizon. And it is also possible to reduce the work-force of the lowest level of employee by 10% for the reasonable management. There are some limitations in computerized data processing, which is only considering the economic costs without considering any external environment of case enterprise. As a result, it is shown that the LP model is very useful method of make aggregate production schedule. schedule.

• 한국군사과학기술학회지
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• 제14권5호
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• pp.850-858
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• 2011

The risk analysis plays an important role in weapon system acquisition project due to uncertainties in the acquisition process. But in domestic, studies on risk analysis are insufficient and risk cost is not included in acquisition budget in policy. Therefore, in this study, we suggest a method that measures risk or success probability of project using the stochastic model. In particular, in order to calculate the success probability, we apply the joint probability distribution model of cost and schedule that are critical factors influencing the project risk. And also we verify the applicability of this model in Korean defence industry environment through case studies.

• 한국경영과학회지
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• 제35권4호
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• pp.33-53
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• 2010

When purchase prices of a raw material fluctuate over time, the total purchasing cost is mainly affected by reordering time. Existing researches focus on deciding the right time when the demand for each period is replenished at the lowest cost. However, the decision is based on expected future prices which usually turn out to include some error. This discrepancy between expected prices and actual prices deteriorates the performance of inventory models dealing with fluctuating purchase prices. In this paper, we propose a new inventory model which incorporates not only cost but also risk into making up a replenishment schedule to meet each period's demand. For each replenishment schedule, the risk is defined to be the variance of its total cost. By introducing the risk into the objective function, the variability of the total cost can be mitigated, and eventually more stable replenishment schedule will be obtained. According to experimental results from crude oil inventory management, the proposed model showed better performance over other models in respect of variability and cost.

• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.169-172
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• 2013

Building Information Modeling (BIM) is an effective decision-making platform that helps to save project cost and enhance quality of construction. By generating and linking a wide variety of objects data, BIM can be effectively utilized, and it should be ensured that object properties maintain consistency throughout the project period of design, estimates, construction, maintenance and repair. This study examined how to utilize BIM data in a construction project, by linking cost and schedule data in web environment, to better utilize the information and maintain consistency of the BIM information. To do so, the model integrated WBS data and CBS data, linked them with BIM model to realize 5D simulation in web environment. As a result, cost and schedule data could be simultaneously acquired, and object properties-cost, schedule, location-as well. These are expected to contribute to developing a BIM-based automatic data-processing system in web environment.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 1998년도 The Korea Society for Simulation 98 춘계학술대회 논문집
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• pp.106-110
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• 1998

Some successful scheduling systems are based on simulation technique. However, they are relatively expensive. A cost-effective solution is to apply general-purpose simulation software to the scheduling system. This paper is concerned with developing a simulation model for MPS(Master Production Schedule) evaluation system. The target system of the model is PC production system. AIM (Analyzer for Improving Manufacturing system), a well-known manufacturing oriented simulation software, is used for modeling tool. Eventually, the model can be included into an MPS evaluation system as simulation module and a scheduler can use the system to verify the MPS in advance.

• 대한토목학회논문집
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• 제42권6호
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• pp.861-868
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• 2022

건설공사의 시공과정에 BIM을 적용하는 목적은 시공 간섭의 파악과 함께 공사일정의 경과에 따른 시공현황의 시각화가 주요 이유이다. 4D시뮬레이션은 이러한 목적의 수행 기능이며, 이를 위해서는 공정별 시작 및 종료일자와 해당 공정의 3D모델이 갖추어져야 하고, 실무적 편리성을 확보하기 위해서는 이러한 기본정보의 활용이 간편한 기능 구성이 필요하다. 본 연구에서는 4D 모델 구성을 간소화하기 위해 설계단계에서 제작된 BIM 모델의 최소한의 속성정보를 활용하여 시공단계에 활용 가능한 공정 정보를 군집알고리즘을 이용해 생성하며 실제 공정관리 정보로서의 활용성을 분석한다.

• 한국BIM학회 논문집
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• 제8권2호
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• pp.10-18
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• 2018

BIM technologies store, share and integrate the information produced in each sector of the construction industry. From this point on, it increases the efficiency of the work. Currently, quantity take-off and process schedule are derived separately based on BIM technology. When calculating the quantity by process, relevant information shall be collected, reinterpreted, and reevaluated as required by the practice. The purpose of this study is to develop an integrated process and quantity management system through BIM collaboration and to build prototypes for steel structures. The main research is to build a construction BIM model for steel structures and a process BIM model through BIM collaboration. Furthermore, necessary information was selected and processed according to the user's needs for integrated management. Relevant integration outcomes are visualized graphically to maximize utilization. Through these studies, a system for integrated control of processes and supplies is provided, and the results are expected to contribute to the improvement of working efficiency and are easily and quickly reflected in design change and process change. In this study, we intended to enhance the usability of information by linking process schedules with quantity calculations based on BIM. Thus, the process for integrated control of the quantity of structural components by process unit and the BIM based schedule information was established. In addition, the efficiency of the information link of the integrated management system was considered for design changes and process schedule changes.

• 국제학술발표논문집
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• The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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• pp.58-65
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• 2011

Construction Productivity is one of the most important elements in construction management. It is used in construction process scheduling and cost management, which are significant sector in construction management. It is important to make appropriate schedule and monitor how works are done within schedule. But construction project contains uncertainty and inexactitude, modifying construction schedule is being an issue to manage construction works well. Even though prediction and monitoring of productivity can be principal activity, it is hard to predict productivity with manager's experience and a standard of estimate. A large number of factors influencing productivity, such as drawing, construction method, weather, labor, material, equipment, etc. But current calculation of productivity depends on empirical probability, not consider difference of each influencing factor. In this research, the aim is to present a productivity predicting regression model of form work, which includes effectiveness of influences factors. 5 variables existed inside form work are selected by interview and site research based on literature review of existed various productivity influencing factors. The effectiveness and correlation of productivity influencing factors are analyzed by statistical approach, and it is used to make productivity regression model. The finding of this research will improves monitoring and controlling of project schedule in construction phase.

• 한국CDE학회논문집
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• 제17권2호
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• pp.111-122
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• 2012

Capacity planning plays an important role not only for master production plan but also for facility or layout design in shipbuilding. Product work breakdown structure, attributes of production resources, and production method or process data are associated in order to make the discrete event simulation model of shipyard layout plan. The production amount of each process and the process time is assumed to be stochastic. Based on the stochastic discrete event simulation model, the production capacity of each facility in shipyard is estimated. The stochastic model of product arrival time, process time and transferring time is introduced for each process. Also, the production capacity is estimated for the assumed master production schedule.

• 대한기계학회논문집A
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• 제25권11호
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• pp.1844-1853
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• 2001

In the present investigation, it was attempted to design the rolling pass schedule fur a clean steel of 0.1C-1.5Mn-0.25Si with the objective of the austenite grain refinement. As the method of approach, a coupled mathematical modeling technique was proposed which consists of a recrystallization model and a flow stress modes. The validity of the coupled model was examined through comparison with results of continuous and discontinuous compression tests at various temperatures, strains and strain rates. The coupled model was incorporated with the finite element method to set up a systematic design methodology far the rolling path schedule for austenite grain refinement. Two path schedules were obtained and discussed in the paper with regard to rolling path time, average grain size, grain size deviation in thickness, etc.