• Journal of the Korea Society of Computer and Information
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• v.21 no.3
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• pp.57-64
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• 2016

This paper deals with the PCB assembly time minimization problem that the PAP (pick-and-placement) machine pickup the K-weighted group of N-components, loading, and place into the PCB placement location. This problem considers the rotational turret velocity according to component weight group and moving velocity of distance in two component placement locations in PCB. This paper suggest heavy-weight component group first pick-and-place strategy that the feeder sequence fit to the placement location Hamiltonean cycle sequence. This algorithm applies the quadratic assignment problem (QAP) that considers feeder sequence and location sequence, and the linear assignment problem (LAP) that considers only feeder sequence. The proposed algorithm shorten the assembly time than iATMA for QAP, and same result as iATMA that shorten the assembly time than ATMA.

• Korean Journal of Computational Design and Engineering
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• v.9 no.4
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• pp.325-333
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• 2004

To ensure competitiveness in the modern automotive market, material arrangements and information managements should be performed concurrently with new car developments. In automotive general assembly shops, thus, new business workflow and supporting environments are inevitable to reduce the manufacturing preparation time in developing a new car in the manner of concurrent and collaborative engineering. Since complete material arrangements for a whole general assembly system is a huge and complex job, several planners should execute their planning jobs and share information. Therefore, each planner should provide others with his/her results with continuous on-line communication and cooperation. Digital automotive general assembly factory is useful the performing concurrent and collaborative engineering and is essential for material arrangements and information managements systems. In this research, we constructed a sophisticated digital factory of an automotive general assembly shop by measuring and modeling through the parametric 3-D CAD, and a web-based system for concurrent and collaborative material arrangements for automotive general assembly via 3D mock-up is developed. By the digital general assembly shop and developed web-based system, savings in time and colt of manufacturing preparation activities are possible, and the reliability of the planning result Is greatly improved.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.11
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• pp.22-35
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• 1999

The block assembly process takes more than half of the total shipbuilding processes. Therefore, it is very important to have a practically useful block assembly process planning system which can build plans of maximum efficiency with minimum man-hours required. However, the process plans are often not readily executable in the assembly shops due to severe imbalance of workloads. This problem arises because the process planning is done on block by block basis in current practice without paying any attention to the load distribution among the assembly shops. this paper presents the development of an automated hull block assembly process planning system which results in the most effective use of production resources and also produces plans that enable efficient time management. If the load balance of assembly shops is to be considered at the time of process planning, the task becomes complicated because of the increased computational complexity. To solve this problem, a new approach is adopted in this research in which the load balancing function and process planning function are iterated alternately providing to each other contexts for subsequent improvement. The result of case study with the data supplied from the shipyard shows that the system developed in this research is very effective and useful.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.3
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• pp.261-268
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• 2008

STATEMENT OF PROBLEM: Detachment of the magnetic assembly from the denture base has been a problem in magnetic overdenture patients. PURPOSE: The objectives of this study were to compare the dislodging force by the fixing materials and the designs of the magnetic assembly, and to compare the effect between the fixing materials and the designs of the magnetic assembly. MATERIAL AND METHODS: Two fixing materials, Jet denture repair $acrylic^{(R)}$ and Super-$Bond^{(R)}$ C&$B^{(R)}$ and two types of magnetic assembly designed with or without wing were used. Each magnetic assembly was fixed in the chamber of the denture base resin block ($Lucitone^{(R)}$199) with each fixing material respectively. These specimens were thermocycled 2,000 cycles in the water held at $4^{\circ}C$ and $60^{\circ}C$ with a dwell time of 1 min each time. Each specimen was seated in a testing jig and then a push-out test was performed with a universal testing machine at a cross head speed of 0.5 mm/min to measure the maximum dislodging forces. RESULTS: Comparing the fixing materials, Super-Bond C&$B^{(R)}$ showed superior dislodging force than Jet denture repair $acrylic^{(R)}$. Comparing the design of the magnetic assemblies, the wing design magnetic assembly showed better dislodging force. Combination of the Super-Bond C&$B^{(R)}$ as a fixing material and wing design magnetic assembly revealed a greatest dislodging force. The kind of fixing material was more influential than the type of magnetic assembly. CONCLUSION: The dislodging force of Super-Bond C&$B^{(R)}$ was significantly higher than Jet denture repair $acrylic^{(R)}$. And the dislodging force of magnetic assembly which have wing design was significantly higher than magnetic assembly which have no wing design.

• Korean Security Journal
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• no.49
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• pp.39-63
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• 2016

After its decision of 'constitutional nonconformity' about a night assembly on September 24th, 2009, then the Korean Constitutional Court decided the 'limited violation of constitution' saying, 'Even a night demonstration should be allowed to be held up to the midnight' on March 27th, 20104. Since such a decision, the revision of Assembly and Demonstration Act has not been done, and the revised act is currently pending on the National Assembly on October, 2016. Amid the controversy about the 'Legislative Deficiency', some articles of the Assembly and Demonstration Act are revised and created like the imposition of the fine about a ghost assembly and the notice duty of fact to hold an assembly, the police superintendent's recommendation about the assembly place and partitioned assembly holding by time in order to protect the people's basic rights and convenience. However, this revised bill of Assembly & Demonstration Act limits the duty of assembly withdrawal report only to overlapping assemblies and a police superintendent can only recommend about the partition of assembly place and time, but has not a certain authority to forcibly enforce, so it is expected that the recommendation will be eventually ended to a formal procedure. And as this revised act has no punishment article concerning the violation of the notice duty within 1 hour before holding an assembly in this revised act, so there is a problem that the police can't force an assembly to follow the article. This study proposed some political suggestions concerning the articles to be supplemented and corrected in the Assembly & Demonstration Act after analyzing its articles around its 2016 revised Act. The Assembly & Demonstration Act has several problems to be continually corrected and supplemented further including the matter of 'Night Assembly & Demonstration' which is in the condition of 'Legislative Deficiency' since 2009.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10b
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• pp.1915-1919
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• 1991

The efficiency of automated assembly line is increased by realizing the automation of each assembly cell, monitoring the line information and developing the real-time line control system it. which production flow is controllable. In this paper, the several modules which are important factors when constructing automated real-time control system, such as, line control S/W module, real-time model change module, error handling module and line production management S/W module, are developed. For developing these important programming modules, real-time control and multi-tasking techniques are integrated. In this paper, operating method of real-time line control in PCB automated assembly line is proposed and for effective control of production line by using multi-tasking technique, proper operating method for relating real-time line control with multi-tasking is proposed by defining the levels of signals and tasks. CIM-Oriented modular programming method considering expandability and flexibility will be added for further research in the future.

• Journal of Institute of Control, Robotics and Systems
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• v.1 no.2
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• pp.112-118
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• 1995

In designing assembly lines, it is required that the lines should not only meet the demand of the product, but also minimize the assembly cost associated with the line. For such a purpose, numerous research efforts have been made on either the assembly sequence generation or the assembly line balancing. However, the works dealing with both the research problems have been seldom reported in literature. When assembly sequences are generated without consideration of line balancing, additional cost may be incurred, because the sequences may not guarantee the minimum number of workstations. Therefore, it is essential to consider line balancing in the generation of cost-effective assembly sequences. To incorporate the two research problems into one, this paper treats a single-model and deterministic (SMD) assembly line balancing (ALB) problem, and proposes a new method for generating line-balanced robotic assembly sequences by using a simulated annealing. In this method, an energy function is derived in consideration of the satisfaction of assembly constraints, and the minimization of both the assembly cost and the idle time. Then, the energy function is iteratively minimized and occasionally perturbed by the simulated annealing. When no further change in energy occurs, an assembly sequence with consideration of line balancing is finally found. To show the effectiveness of the proposed scheme, a case study for an electrical relay is presented.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.5
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• pp.87-92
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• 2005

In this study, an automation assembly jig for the automation assembly process for the ventilation grille that is used in the interior of a car Is developed. As the method that can do the automation assembly for the ventilation grille, a simple jig and air cylinder have been applied. And a solenoid valve, a filter regulator, and on-off switch have been used in controlling the system. Moreover, the timer is attached to the equipment so that a worker may control the assembly time, as fitting the quantity on demand of production. Actually with executing the assembly test productivity and performance of assembly have been verified. In case of the automation assembly work for a ventilation grille is compared to the manual work. The optimum working speed has been identified to make the process twice or three times better.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.10a
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• pp.77-82
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• 2000

In this study, an automation assembly jig for the automation assembly process for the ventilation grille that is used in the interior of a car is developed. As the method that can do the automation assembly for the ventilation grille, a simple jig and air cylinder have been applied. And a solenoid valve, a filter regulator, and on-off switch have been used in controlling the system. Moreover, the timer is attached to the equipment so that a worker may control the assembly time, as fitting the quantity on demand of production. Actually with executing the assembly test productivity and performance of assembly have been verified. In case of the automation assembly work for a ventilation grille is compared to the manual work. The optimum working speed has been identified to make the process twice or three times better.

• International Journal of Precision Engineering and Manufacturing
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• v.1 no.2
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• pp.35-42
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• 2000

To save time and cost in assembly process and to improve th quality of products, it is very important to choose and optimal assembly sequence. In this paper, we propose a methodology that generates an optimal assembly sequence by using various methods and the knowledge of experts. To illustrate the effectiveness of the proposed methodology, a knowledge-based system is developed, The built system is applied to the case of UBR(Unit Bath Room). The applying result showed the applicability of the developed system.