• Journal of Institute of Control, Robotics and Systems
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• v.8 no.3
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• pp.270-274
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• 2002

This paper presents a teleoperation system that combines computer network and an autonomous mobile robot. We control remotely an autonomous mobile robot with vision over the Internet to guide it under unknown environments in the real time. The main feature of this system is that local operators need a web browser and a computer connected to the communication network and so they can command the robot in a remote location through the home page. The hardware architecture of this system consists of an autonomous mobile robot, workstation, and local computers. The software architecture of this system includes the client part for the user interface and robot control as well as the server part for communication between users and robot. The server and client systems are developed using Java language which is suitable to internet application and supports multi-platform. Furthermore. this system offers an image compression method using JPEG concept which reduces large time delay that occurs in network during image transmission.

• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.6
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• pp.787-796
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• 2008

When the manipulator collides with surroundings, there occurs an impulse. To reduce the impulse, the self motion should maintain the manipulator's position by the minimally effective mass. At this time, we can use the local joint torque minimization algorithm to resolve the redundancy. In this study, to reduce the impulse and damages by the impact between the manipulator and surroundings, new control algorithm for the minimization of the joint torque using the kinetic redundancy and the impact minimization is proposed. It adapts fuzzy logic and genetic algorithm to the conventional local joint torque minimization algorithm. The proposed algorithm is applied to a 3-DOF redundant planar manipulator. Simulation results show that the proposed algorithm works well.

• Journal of Digital Convergence
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• v.9 no.3
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• pp.191-202
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• 2011

Public agencies and local governments have been installing CCTV cameras for the prevention of crime, traffic jam, and unauthorized waste. Additionally, national government agencies and schools, a special corporation by special law, local construction and industrial company installed CCTV cameras of their own and are operating them. Various types of CCTV systems disclosed technical heterogeneity. In February, 2011, Ministry of Public Administration and Security presented guidelines for building an integrated control center. This study examines the case of Busan by using the administrative guidelines. Busan integrated CCTV control center among themselves, police agency and fire department. This study looks into the potential problems with the integration process of CCTV cameras and proposes a solution to them.

• Journal of Communications and Networks
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• v.18 no.3
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• pp.502-512
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• 2016

The wireless carrier sense multiple access with collision detection (WCSMA/CD) and carrier sense multiple access with collision resolution (CSMA/CR) protocols are considered representative distributed collision detection protocols for fully connected dense wireless local area networks. These protocols identify collisions through additional short-sensing within a collision detection (CD) period after the start of data transmission. In this study, we analyze their throughput numerically and show that the throughput has a trade-off that accords with the length of the CD period. Consequently, we obtain the optimal length of the CD period that maximizes the throughput as a closed-form solution. Analysis and simulation results show that the throughput of distributed collision detection protocols is considerably improved when the optimal CD period is allocated according to the number of stations and the length of the transmitted packet.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.10a
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• pp.301-306
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• 2009

High strength steels are widely used for lightweight automobile parts and the control of springback is very important in sheet metal forming. The object of this study is to develop the forming process for stair type side sill made of high strength steel, DP780. Stair type side sill with local formed area and geometry change area can improve stiffness and design freedom but there are a few studies for forming process. The forming technology considered in this paper is form type process, which have many advantages for farming of high strength steel compared with draw type process. Finite element analysis is carried out to predict formability and springback. It is shown that angle calibration of die is essential for reducing springback, and local forming involving bead is effective to control springback also. The effectiveness of local forming and angle calibration is verified by experimental.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.7
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• pp.664-668
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• 2012

Hierarchical IPP (Integrated Path Planning) combining the GPP (Global Path Planner) and the LPP (Local Path Planner) is interesting the researches who study about the mobile vehicle in recent years. However, in this study, there is the path mismatch problem caused by the difference in the map information available to both path planners. If ever a part of the path that was found by the GPP is available to mobile vehicle, the part may be unavailable when the mobile vehicle generates the local path with its built-in sensors while the vehicle moves. This paper proposed the TWR (Temporal Waypoint Reviser) to solve the path mismatch problem of the hierarchical IPP. The results of simulation provide the performance of the IPP with the TWR by comparing with other path planners.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.3
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• pp.361-365
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• 1993

An experiment was conducted to investigate the effects of feeding fresh cassava roots on the performance and carcass quality of pigs raised from $15{\pm}1kg$ to 85 kg live weight. Fresh unpeeled cassava roots were chopped into chips and offered separately along with a protein concentrate made up of copra cake and meat and bone meal, and a local mineral-vitamin premix. Commercial pig grower and finisher diets served as control. A total of 24 pigs were used in an incomplete randomized split-plot design experiment. Pigs fed fresh cassava-based diet grew as fast, 0.78 vs 0.77 kg/day, and were as efficient, 3.74 vs 3.77 in converting feed into body weight gain as those fed the commercial control diet. Similarly, there were no differences in carcass quality measured in terms of dressing percentage, 77 vs 77; backfat thickness, 2.76 vs 2.78 cm; loin eye muscle area, 29.2 vs $29.1cm^2$ and in the relative proportions of the different carcass cuts between the two dietary treatments. The use of fresh cassava along with the protein and the local mineral-vitamin premix however, resulted in lowered total feed cost and cost per unit of live weight gain. It is concluded that fresh cassava roots can be fed along with copra cake, meat and bone meal protein concentrate and a local mineral-vitamin premix to fattening pigs with no adverse affects on performance and carcass quality.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.8 no.1
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• pp.15-21
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• 2012

Extraction of all nonrestorable teeth prior to bone marrow transplantation is the major dental management of the patient being prepared for the transplantation. But, there are four principal causes for excessive bleeding in the immediate postextraction phase ; (1) Vascular wall alteration (wound infection, scurvy, chemicals, allergy) (2) Disorders of platelet function (3) Thrombocytopenic purpuras (4) Disorders of coagulation (liver disease, anticoagulation drug-heparin, coumarin, aspirin, plavix) If the hemorrhage from postextraction wound is unusually aggressive, the socket must be packed with local hemostatic agent and wound closure & pressure dressing are applied. But, in dental alveoli, local hemostatic agent (gelfoam, surgcel etc) may absorb oral microorganisms and cause alveolar osteitis (infection). This is a case report of bleeding and infection control by suture, pressure packing and iodoform gauze drainage on infected active bleeding extraction socket under sedation and local anesthesia in a 57-years-old multiple disabled patient with anticoagulation drug.

• Journal of Broadcast Engineering
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• v.21 no.1
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• pp.51-59
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• 2016

This paper presents a method of DCT-based illuminant compensation to enhance the accuracy of face recognition under an illuminant change. The basis of the proposed method is that the illuminant is generally located in low-frequency components in the DCT domain. Therefore, the effect of the illuminant can be compensated by controlling the low-frequency components. Moreover, a directional high-order local pattern descriptor is used to detect robust features in the case of face motion. Experiments confirm the performance of the proposed algorithm got up to 95% when tested using a real database.

• Journal of environmental and Sanitary engineering
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• v.17 no.2
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• pp.26-33
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• 2002

Ultimate objective of industrial hygiene is the prevention of health impairment that may result from exposure to chemicals at workplace. Workers in solvent thinner-using occupation environment may be highly exposed to VOCs (volatile organic compounds) because solvent thinner has been used extensively such as painting, spraying, degreasing, coating and so on in Korea. The purpose of this study was to recognize, evaluate, and propose the control methods of VOCs from solvent thinner-using workplace. Five target volatile organic compounds (benzene, toluene, ethylbenzene, o-xylene, and m-xylene) were monitored in H company of Shiwa Industrial Complex and analyzed in perosnal, occupational indoor and outdoor during working hours simultaneously. Engineering control such as local ventilation should be made in considering the long-term exposure, though measured VOCs concentration did not exceed the workplace exposure standards. In addition, air cleaning device should be installed in local ventilation because Shiwa Industrial Complex has had the serious ambient air pollution. Currently, environmental purification using $TiO_2$ photocatalyst have attracted a great deal of attention with increasing number of recent environmental problems. In this study, $TiO_2$ sol coated on the ceramic bead was prepared by sol-gel method and the photodegradation of target compounds was investigated in gas phase by the exposure to UV-A lamp(365nm) in a batch system.