• IE interfaces
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• v.12 no.3
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• pp.468-479
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• 1999

Lean production system can be defined as customer(product)-oriented production system with small lot size and flow-shop layout based on the JIT(Just-in-time) principles. In this paper, we introduce a case example of implementation of the Lean product ion system for manufacturing line of electronic component which has both machine processes and manual jobs. We also investigate the issues of implementing the Lean production system with the viewpoints of layout design scheme and JIT management rules. In the layout design, we propose the cell-line which has flow-shop layout with small lot size. In the management rules, the superior cell rule is applied in order to boost the needs of kaisen up. As the results of implementing the Lean production system, production lead time is decreased from 5 days to 1.5 days and also productivity and quality level arc surprisingly increased.

• Journal of the Korea Safety Management & Science
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• v.9 no.4
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• pp.129-136
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• 2007

This paper considers the sequencing of products in mixed model assembly lines under Just-In-Time (JIT) systems. Under JIT systems, the most important goal for the sequencing problem is to keep a constant rate of usage every part used by the systems. The sequencing problem is solved using Genetic Algorithm Genetic Algorithm is a heuristic method which can provide a near optimal solution in real time. The performance of proposed technique is compared with existing heuristic methods in terms of solution quality. Various examples are presented and experimental results are reported to demonstrate the efficiency of the technique.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.17 no.32
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• pp.155-162
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• 1994

The Japanese "Just-In-Time" technique reduces inventory and unnecessary factors. This technique makes the success of Japanese firms, therefore many Korean firms try to apply it to their situation. But the technique doesn't bare the same success in Korean firms. This paper, therefore, considers the different situations between Korean rim and Japanese firm, then simulates the Pull system and Push system for a multiline, multistage production system. This paper drives the different results of simulation according to variable processing times, variable demand, set-up time and shortages in Pull system and Push system using GPSS. The results show that the performance of Pull system is lower than Push system's in variable master production scheduling and variable processing times.ing times.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2006.11a
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• pp.161-166
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• 2006

Recently various applications have been proposed to improve supply chain process and management by not only using various management theories such as JIT(just In Time) and SCM(Supply Chain Management) but also utilizing emerging technology like RFID(Radio Frequency Identification). But existing research was merely focused on the use of the theories and technology on a particular work or material. Therefore, the objective of this study is to derive basic types of construction supply chain management which spans from manufacturing to installation at the construction site. This research proposes the seven types of construction supply chain processes, which has been derived based on the progress management theory and budget items for construction project. It is expected that the result of this study can be applied for RFID-based construction supply chain management as well as more efficiencies in various management areas.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2006.11a
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• pp.150-153
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• 2006

GS E&C had developed the construction management system, PMS which is based on EVMS in 1997. Recently, TPMS has developed for effective construction management through applying daily schedule management and JIT on material, labor, equipment focusing field work. TPMS realizes "Shielding" and "Make-Ready Process" which are the main concept of Lean construction. Through this system, it can manage and plan daily field work, support the field work related material, labor, and equipment planning, and minimizes the non-valuable process. This paper introduces the concept of TPMS, and through established system, it can lead the construction culture and raise the competitive power of construction industry

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.341-344
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• 2003

There are many problems in management of high-rise building construction performed in downtown area due to limited spaces and equipments for increasing kinds and quantities of material. By these restrictions, problems such as increase of construction cost. delay of construction period, decrease of productivity, occurrence of accident are caused. Recently, studies on JIT concept have focused on construction materials as a solution for the problems. But, studies about finishing material are insufficient yet. Accordingly, this study suggests flowing of current material management, JIT management effect, and development direction of lifting-up and procurement system with Low-emissivity double Glazing, among of main finishing materials.

• Journal of the Korean Operations Research and Management Science Society
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• v.17 no.3
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• pp.13-26
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• 1992

Set-up reduction is an important aspect of the Japanese Just-In-Time (JIT) and Zero Inventory (ZI) concepts. In this paper, we first analyze the effects of set-up cost reduction on tatal inventory, average lot size and forecast horizon in the dynamic lot size model. We also examine the various effects of set-up cost reduction in the EOQ model and explain why many Japanese firms try to cut set-up cost and/or set-up time greatly.

• Journal of Korean Institute of Industrial Engineers
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• v.34 no.1
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• pp.1-12
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• 2008

The Kanban system in Just-In-Time (JIT) production is very effective in reducing the inventories when consumption rate of the final product is relatively stable. When large fluctuations exist in the consumption rate, a new production ordering policy in which the production order quantity is determined by smoothing the demands exponentially is more suitable. This new ordering policy has not been investigated sufficiently. In this research, a multi-stage production and inventory system with stock points for materials and finished items located at each stage is considered. Approximations of average inventories at each stage in the system are derived theoretically. Numerical simulations are carried out to assess the accuracy of approximations and to evaluate the effectiveness of the new ordering policy as compared with the Kanban system. As a result, it is shown that the new ordering policy can achieve significantly lower inventory costs than the original Kanban system. The new ordering policy thus emerges as a key concept for an effective supply chain management.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.43
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• pp.1-16
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• 1997

This paper improves the autonomy for supplier's schedule and the flexibility of the final assembly line. The final assembly line is a single work station and each product taking different assembly time is considered. In the assembly schedule, the heuristic method based on the goal chasing method is used. Consequently, suppliers can independently determine their output rates and thus, change their workload pattern according to their needs and priorities. Moreover, this flexibility can help to avoid expensive final-assembly-line stoppages in case of sudden part supply disruptions. The sequencing method can be easily implemented into an existing just-in-time system. In addition, the mathematical model was formulated and the algorithm was explained through the flow chart. The numerical example was given and the efficiency of this method is shown through the analysis of computational results of that example.

• ETRI Journal
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• v.37 no.5
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• pp.1001-1011
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• 2015

Since just-in-time (JIT) has considerable overhead to detect hot spots and compile them at runtime, using sophisticated optimization techniques for embedded devices means that any resulting performance improvements will be limited. In this paper, we introduce a novel static Dalvik bytecode optimization framework, as a complementary compilation of the Dalvik virtual machine, to improve the performance of Android applications. Our system generates optimized Dalvik bytecodes by using Low Level Virtual Machine (LLVM). A major obstacle in using LLVM for optimizing Dalvik bytecodes is determining how to handle the high-level language features of the Dalvik bytecode in LLVM IR and how to optimize LLVM IR conforming to the language information of the Dalvik bytecode. To this end, we annotate the high-level language features of Dalvik bytecode to LLVM IR and successfully optimize Dalvik bytecodes through instruction selection processes. Our experimental results show that our system with JIT improves the performance of Android applications by up to 6.08 times, and surpasses JIT by up to 4.34 times.