• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.10a
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• pp.93-96
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• 2008

If a fluorescent lamp be used too much time, the filmy part of electronic emission in the lane that is attached near the tube of the cathode brings about blacking. Luminance output and luminous efficiency are decreased. So, it's necessary to replace it. if the user doesn't replace the lamp for a long time, it causes overvoltage in the lamp. Therefore, the filament might be overheated. Even the socket of the lamp might catch on fire. In this paper gives development model of the fluorescent lighting equipment which has ramp shift timely display device.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.366-368
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• 2000

When faults occur in transmission lines, the classification of faults is very important. If the fault is HIF(High Impedance Fault), it cannot be detected or removed by conventional overcurrent relays (OCRs), and results in fire hazards and causes damages in electrical equipment or personal threat. The fast discrimination of fault needs to effective protection and treatment and is important problem for power system protection. This paper proposes the fault detection and discrimination algorithm for LIFs(Low Impedance Faults) and HIFs(High Impedance Faults). This algorithm uses artificial neural networks and variation of 3-phase maximum currents per period while faults. A double lines-to-ground and line-to-line faults can be detected using Neural Network. Also, the other faults can be detected using the value of variation of maximum current. Test results show that the proposed algorithms discriminate LIFs and HIFs accurately within a half cycle.

• Journal of Environmental Science International
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• v.15 no.4
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• pp.341-347
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• 2006

Adsorption characteristics of benzene by zeolite were investigated using irradiating microwave. Experimental apparatus was applied to a U-type fix-bed column equipped with microwave system. Zeolite, itself, seems to be inappropriated to remove benzene because of a hygroscopic property, Microwave irradiation to zeolite, however, brings about decreasing $H_{2}O$ adsorption and increasing benzene adsorption. This causes that the dipole material such as $H_{2}O$ was vibrated and heated by irradiation of microwave and desorbed from zeolite. And then, benzene starts to be absorbed by zeolite. In this study, the results showed that the selective adsorption of benzene was occurred by the microwave irradiation and the adsorption capacity of benzene was increased by increasing microwave energy. As a results, it was found that the zeolite could be used to adsorb benzene with microwave and this method make it feasible simultaneously to adsorb and desorb benzene.

• Korean Journal of Computational Design and Engineering
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• v.19 no.2
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• pp.169-181
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• 2014

Recently ships and ocean platforms are becoming increasingly technological, unmanned, and huge. Maintenance and safety monitoring of these products is very important for safety reasons. Therefore, real-time monitoring of safety regions, such as the engine room, and hull structure, and environmental states, like fire and pressure of LNG tanks, is required for the sustainable ships. In this paper, a ZigBee-based wireless sensor network is suggested to monitor ships and ocean platforms effectively. However, this causes some telecommunication problems because these products are made of steel. To resolve this problem, we use the mesh networking of Zig-Bee that can monitor the regions and environmental states consistently. The telecommunication of such a monitoring system is tested on a real container ship and its performance is verified. The real-time monitoring results are displayed on the users' smart devices.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.6
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• pp.86-95
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• 2003

The object of this paper is to correct check the tree situation and quantity around highway. Also, those data utilize in order to establish plan about how to the long and short term landscape construction and maintain program. The result of this study can be summarized as follows; 1. Tree decrease rates for 8 branch offices were Jongbu(5.62%), Gangwon(4.32%), Chungcheong (3.35%), Honam(5.62%), Gyeongbuk(3.06%), Gyeongnam(5.60%), Seorak training center(0.31%), Headquarter(1.54%). Also decrease causes were traffic accidents(1.8%), air po11ution(4.7%), humid damage(0.9%), insect and disease(1.2%), wind and rainfall(3.4%), dry damage(3.5%), cold damage (1.0%), fire(3.1%), damage of the man and anima1(4.1%), remove bad tree(13.1%), bad rooting(9.5%) and etc.(53.7%). 2. Improve methods of tree death problems were regulation management(ferti1ize, irrigation and pesticide work), improvement of draining system, Pull out the weeds, Plant native plants, utilize organic matter fertilize and plant environment trees.

• Korean Journal of Acupuncture
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• v.22 no.3
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• pp.175-197
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• 2005

Objective : The purpose of this study is to review the acupuncture therapy and moxibustion on itching Method : We searched and reviewed chinese journals of and books of the acupuncture therapy and moxibustion on itching. Results & Conclusions : 1. Dermatopathy of itching is described as eczema, neurotic-dermititis, itching in orient medical text. 2. According to text, itching causes were wind symptom produced by deficiency of blood, deficiency syndrom of the spleen, and damp-heat. 3. Frequently used acupoints were LI10(41 frequency), SP10(29), ST36(27), SP6(22), GB20(19), Asi point(18), BL(17), back Su acupoints(13), LI4(13), SP9(10), PC6(7), HT7(7). etc 4. The practice of acupuncture was used by body acupuncture, auriculo-theraphy, loss of bleeding with needle, blum-blosson needle, dermal needle, fire needle. etc. 5. Moxibustions are mild moxibustion, non-scar producing moxibustion, herb- moxibustion. etc.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.37-42
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• 2006

The voltage drop in electrical circuits causes a heat accumulation of wiring. This heat could change the specific character of an insulator and deteriorate the dielectric strength so that it could affect an electric leakage, an electric ant a power failure and a fire caused by the short circuit. Therefore optimal design for voltage drop in electrical wiring became an important factor to ensure the safety and economical efficiency of electrical facilities. So in this paper, I analyzed consequences that voltage drop affects in electrical wiring in multi-distributed system used for low electrical system such as road lights, Building, subway station which needs securities for the public society. And I proposed voltage drops computation program and optimal design to ensure the safety and economical efficiency.

• Journal of the Korean Society of Propulsion Engineers
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• v.4 no.3
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• pp.38-44
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• 2000

In general liquid rocket nozzles are protected from hot combustion gas by regenerative cooling techniques. But due to the complexity of the cooling system, it causes increase of system cost and frequently source of the system malfunction. Recently, instead of regenerative cooing, ablative material are used to protect combustion chamber wall and nozzle. To determine the nozzle material erosion rate and erosion shape, more than 500 hot fire test were performed by using 100 lb thrust experimental liquid rocket. Test variable were propellant feed sequence, injector, position of igniter and liquid oxygen supply temperature.

• Journal of the Korean Society for Marine Environment & Energy
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• v.8 no.4
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• pp.193-202
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• 2005

Marine risk assessment considers events such as collision/grounding, sinking/capsize, fire/explosion and flooding, developing relationships between their causes and effects. In addition, risk assessment of previously sunken ships are also necessary since they continuously have possibility for further oil spill or can cause other marine accidents. The objective of this paper is to develop the risk assessment systems for sunken ships to prevent oil spill and further marine causalities in order to preserve safe and clean oceans around Korea peninsula. The risk assessment systems for sunken ships comprise of database management sub-system for sunken ships, qualitative risk assessment sub-system, quantitative risk assessment sub-system, and cost-benefit analysis subsystem.

• Journal of the Korean Society of Systems Engineering
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• v.16 no.1
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• pp.68-77
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• 2020

The shipbuilding and offshore industry is a large and complex assembly industry, which causes many safety accidents. The major accidents in the shipbuilding and offshore industry workplaces are stenosis, falling objects, dust, fire, explosions, and gas poisoning. The accident by worker in this industry mainly has three factors: frequent movement, narrow work space, and increased use of subcontractors. To control these factors, it is necessary to monitor the worker's location and work status. In this paper, a worker location monitoring system using inaudible sound wave was designd that can be used in environments with many metal barriers. The process included deriving stakeholder requirements, transforming to system requirements, designing system architecture, and developing prototype. The prototype was validated by third-party testing agency. As a result, it satisfied the designed performance and verified its feasibility.