• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.176-180
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• 2001

There are several factors causing re-work in CMP process such as improper polish time calculation by operator. removal rate decline of the polisher, unstable in-suit pad conditioning, slurry supply module problem and wafer carrier rotation inconsistancy. And conclusively those fundimental reason for the re-work rate increasement is mainly from the cycle time delay between wafer polish and post measurement. Therefore, Wafer thickness measurement in wet condition could be able to remove those improper process conditions which may happen during the process in comparison with the conventional dried wafer measurement system and it can be able to reduce the CMP process cycle time. CMP scrap reduction by overpolish, re-work rate reduction, thickness control efficiency also can be easily achieved. CMP Equipment manufacturer also trying to develop integrated system which has multi-head & platen, cleaner, pre & post thickness measure and even control the polish time from the calculated removal rate of each polishing head by software. CMP re-work problem such as over & under polish by target thickness may result in the cycle time delay. By reducing those inefficient factors during the process and establish of the automatic process control, CLC system need to be adopted to maximize the process performance. Wafer to Wafer Polish Time Feed Back Control by measuring the wafer right after the polish shorten the polish time calculation for the next wafer and it lead to the perfact Post CMP target thickness control capability. By Monitoring all of the processed the wafer, CMP process will also be stabilize itself.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.176-180
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• 2001

There are several factors causing re-work in CMP process such as improper polish time calculation by operator, removal rate decline of the polisher, unstable in-suit pad conditioning, slurry supply module problem and wafer carrier rotation inconsistency. And conclusively those fundimental reason for the re-work rate increasement is mainly from the cycle time delay between wafer polish and post measurement. Therefore, Wafer thickness measurement in wet condition could be able to remove those improper process conditions which may happen during the process in comparison with the conventional dried wafer measurement system and it can be able to reduce the CMP process cycle time. CMP scrap reduction by overpolish, re-work rate reduction, thickness control efficiency also can be easily achieved. CMP Equipment manufacturer also trying to develop integrated system which has multi-head & platen, cleaner, pre & post thickness measure and even control the polish time from the calculated removal rate of each polishing head by software. CMP re-work problem such as over & under polish by target thickness may result in the cycle time delay. By reducing those inefficient factors during the process and establish of the automatic process control, CLC system need to be adopted to maximize the process performance. Wafer to Wafer Polish Time Feed Back Control by measuring the wafer right after the polish shorten the polish time calculation for the next wafer and it lead to the perfect Post CMP target thickness control capability. By Monitoring all of the processed the wafer, CMP process will also be stabilize itself.

• Journal of the Korea Safety Management & Science
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• v.13 no.1
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• pp.183-188
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• 2011

Management of maintenance parts in the aircraft have difficulty because of high cost of part, necessity of separate managements, and very many kinds of parts. The serial number of parts was used in maintenance process and then the results was depended on worker's ability. Also the workers used printed work order and manual at every time in maintenance processes. In this study, we analyzed the maintenance process and the information that occurs in the material warehouse and hangar for large airline company to solve the problems about inventory and visualization. Based on above analysis we developed the maintenance process with integrated by information technologies such as QR code and tablet PC. We expect the reduced errors resulting from visually checking and decreased work hours and maintenance cost and will finally develop the smart work.

• Journal of Radiation Protection and Research
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• v.48 no.1
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• pp.20-27
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• 2023

Background: As the number of nuclear facilities nearing their pre-determined design life increases, demand is increasing for technology and infrastructure related to the decommissioning and decontamination (D&D) process. It is necessary to consider the nature of the dismantling environment constantly changing and the worker doing new tasks. A method was studied that can calculate the effect of learning and the change in work time on the work process, according to the learning-forgetting curve model (LFCM). Materials and Methods: The LFCM was analyzed, and input values and scenarios were analyzed for substitution into the D&D process of a nuclear facility. Results and Discussion: The effectiveness and efficiency of the training were analyzed. It was calculated that skilled workers can receive a 16.9% less collective radiation dose than workers with only basic training. Conclusion: Using these research methods and models, it was possible to calculate the change in the efficiency of workers performing new tasks in the D&D process and the corresponding reduction in the work time and collective dose.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.70-71
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• 2014

The structural work is the main process of building construction which influence on the time, cost, safety and quality. The form work is one of the main process which has from 20 to 30 percentage of structural work. Especially the form work for beams is complex and need more manpower compared with form work for column or slab. When the existing forms such as plywood form, steel framed wooden form and aluminum form, is used for form work of beam, it would result in the cost overrun caused by needs of lots of manpower and resources. Therefore, the aim of this study is analysis of the requirement for development of SMART beam form. The result of this study shall be used for the development of SMART form work system.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.1
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• pp.79-86
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• 2017

This research focused on deciding optimal manufacturing WIP (Work-In-Process) limit for a small production system. Reducing WIP leads to stable capacity, better manufacturing flow and decrease inventory. WIP is the one of the important issue, since it can affect manufacturing area, like productivity and line efficiency and bottlenecks in manufacturing process. Several approaches implemented in this research. First, two strategies applied to decide WIP limit. One is roulette wheel selection and the other one is elite strategy. Second, for each strategy, JIT (Just In Time), CONWIP (Constant WIP), Gated Max WIP System and CWIPL (Critical WIP Loops) system applied to find a best material flow mechanism. Therefore, pull control system is preferred to control production line efficiently. In the production line, the WIP limit has been decided based on mathematical models or expert's decision. However, due to the complexity of the process or increase of the variables, it is difficult to obtain optimal WIP limit. To obtain an optimal WIP limit, GA applied in each material control system. When evaluating the performance of the result, fitness function is used by reflecting WIP parameter. Elite strategy showed better performance than roulette wheel selection when evaluating fitness value. Elite strategy reach to the optimal WIP limit faster than roulette wheel selection and generation time is short. For this reason, this study proposes a fast and reliable method for determining the WIP level by applying genetic algorithm to pull system based production process. This research showed that this method could be applied to a more complex production system.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.11
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• pp.45-54
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• 2018

The primary objective of this study is to develop a conceptual design of all-in-one attachment based steel pipe pile cutting robot that improves the conventional work in safety, quality, convenience and productivity. For this, the following research works are conducted sequentially; 1)literature review, 2)field investigation, 3)selection of element technology for conceptual design, 4)deduction of conceptual design and its work process, 5)technical feasibility analysis of the conceptual design and its work process. As a result, leveling laser and laser detector, plasma cutter, rotary grapple are selected as core technologies. Futhermore, a conceptual design and work process of an all-in-one attachment based steel pipe pile cutting robot are developed based on the core technologies. According to the technical feasibility analysis result, at least 76.8% of the respondents are selected positive answer about each device of the all-in-one attachment based steel pipe cutting robot. It is expected that the application range and impact on the construction industry will be enormous due to the increasing trend of the steel pipe pile market.

• Korean Journal of Construction Engineering and Management
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• v.18 no.2
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• pp.58-70
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• 2017

The planning for material lifting operations is one of the key processes in high-rise building construction. Several previous studies have used rough calculations by referring to existing practices or establishing a target value for lifting cycle time or operating rate. Therefore, the purpose of this study is to propose a material lifting process optimization method for reducing the lifting cycle time and increasing the operating rate. In this study, we improve the cyclic operation network (CYCLONE) modeling method that considers the duration and zone information of each work task. This method can be used to hand over work tasks to another crew group in the work process. According to this methodology, this study optimizes the material lifting process, performs a sensitivity analysis, and evaluates the field applicability of the proposed material lifting process optimization method. Therefore, the optimized process was then applied to a high-rise building construction site. The lifting work process time and operating rate for the simulated as - is lifting process data, optimized process data, and field application result data were compared for each lifting height. From this comparison, the effectiveness of the optimization methodology was confirmed.

• Journal of the Korea Convergence Society
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• v.6 no.6
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• pp.57-63
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• 2015

The objective of this research is to find out how strategy development and deployment effect on patients satisfaction, employee satisfaction, and work process in Korean hospitals. Previous researches suggested when establish a strategy had to reflect internal ability which are work process, employee satisfaction and others and external ability which are patients satisfaction and others. As a results, strategy development positive influence on patients satisfaction, employee satisfaction and work process, and strategy deployment positive influence on patients satisfaction, employee satisfaction and work process as well. Patients satisfaction positive influence on hospital performance and work process influence on hospital performance but employee satisfaction is not.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.1253-1253
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• 2022

Although the construction industry is changing from a 2D-based to a 3D BIM-based management process, 2D drawings are still used as standards for permits and construction. For this reason, 2D deliverables extracted from 3D BIM are one of the essential achievements of BIM projects. However, due to technical and institutional problems that exist in practice, the process of extracting 2D deliverables from BIM requires additional work beyond generating 3D BIM models. In addition, the consistency of data between 3D BIM models and 2D deliverables is low, which is a major factor hindering work productivity in practice. To solve this problem, it is necessary to build BIM data that meets information requirements (IRs) for extracting 2D deliverables to minimize the amount of work of users and maximize the utilization of BIM data. However, despite this, the additional work that occurs in the BIM process for drawing creation is still a burden on BIM users. To solve this problem, the purpose of this study is to increase the productivity of the BIM process by automating the process of extracting 2D deliverables from BIM and securing data consistency between the BIM model and 2D deliverables. For this, an expert interview was conducted, and the requirements for automation of the process of extracting 2D deliverables from BIM were analyzed. Based on the requirements, the types of drawings and drawing expression elements that require automation of drawing generation in the design development stage were derived. Finally, the method for developing automation technology targeting elements that require automation was classified and analyzed, and the process for automatically extracting BIM-based 2D deliverables through templates and rule-based automation modules were derived. At this time, the automation module was developed as an add-on to Revit software, a representative BIM authoring tool, and 120 rule-based automation rulesets, and the combinations of these rulesets were used to automatically generate 2D deliverables from BIM. Through this, it was possible to automatically create about 80% of drawing expression elements, and it was possible to simplify the user's work process compared to the existing work. Through the automation process proposed in this study, it is expected that the productivity of extracting 2D deliverables from BIM will increase, thereby increasing the practical value of BIM utilization.