• Proceedings of the Korean Society of Toxicology Conference
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• 2003.05a
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• pp.68-69
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• 2003

Tributyltin (TBT) used world-wide in antifouling paints for ships is a widespread environmental pollutant and cause reproductive organs atrophy in rodents. At low doses, antiproliferative modes of action have been shown to be involved, whereas at higher doses apoptosis seems to be the mechanism of toxicity in reproductive organs by TBT. (omitted)

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.05a
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• pp.6.2-8
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• 1996

The NO$_2$ GAS-detection characteristic of CuTBT (Copper-tetra-tert-butylphtha1ocyanine) LB films were investigated through a study of current-voltage (I-V) characteristics with a variation of number N of interdigital electrodes (N=1∼25). A concentration of 200ppm NO$_2$ gas was used. It was found that a conductance G increases monotonically as the number of interdigital electrode increases, and a sensitivity $\Delta$G ($\Delta$G=G$\_$gas//G$\_$air/) is at least higher than 50 and stable. As far as a sensitivity is concerned, the sensitivity when N=26 is greater than that when N=1 by 70 or so. It indicates that the number of interdigital electrodes affects the currents, sensitivity and stability.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2002.11a
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• pp.25-32
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• 2002

유기주석화합물은 선박방오도료에 살생물제로 쓰이는 독성이 강한 물질로서 내분비계장애물질의 일종으로 알려지고 있다. 광양만에서 유기주석화합물의 오염현황을 파악하고자 표층퇴적물 및 생물체 중의 농도를 정성 및 정량분석하였으며, 생물에 미치는 영향을 파악하고자 복족류의 임포섹스(암컷에서 수컷의 성기가 발현되는 현상)를 측정하였다. 표층퇴적물 및 생물체 체내에서 phenyltin은 일부 정점을 제외하고는 모두 검출한계 이하의 값을 보였으나, butyltin은 대부분의 정점에서 검출되었다. 표층퇴적물, 참굴, 대수리 체내의 tributyltin (TBT)의 농도는 각각 미검출-29 ng/g, 178-2458 ng/g, 47-236 ng/g 범위를 보였다. TBT 화합물의 공간적인 분포는 선박활동과 밀접한 관련이 있었으며, 항구가 위치한 여수 인근을 제외하고는 광양내만에서 상대적으로 높은 값을 보였다. 한편 대수리 중의 임포섹스는 11개 정점에서 모두 관찰되었으며, 상대성기길이 지수는 47.9-107.8%의 범위를 보였다.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2002.11a
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• pp.154-162
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• 2002

인간이나 환경에 해로운 영향을 주는 지속성 유기오염물질의 독성을 동물플랑크톤 중 요각류를 대상으로 실험하였다. 실험에 사용된 요각류는 장목만에서 주로 가을에 많은 출현을 보인 Acartia erythraea와 늦가을부터 그 다음해 봄까지 우점하는 A. omorli였다. 지속성 유기오염물에 대한 요각류의 독성을 평가하기 위해 3가지의 실험을 실시하였다. 광양만에서 주로 나타나는 5가지 PAHs에 대한 A. omorli 48h-LC50을 구하였고, 온도에 따른 Benzo(a)pyrene과 TBT의 독성의 변화를 Brine shrimp(Artemia)를 이용해 실험하였으며, PAHs 중에서 독성이 강한 Benso(a)Pyrene에 노출된 먹이를 섭취한 Acartia erythraea와 A. omorli의 egg Production, hatching rate, fecal Pellet의 변화를 측정하였다. A. omorli의 48h-LC50으로 조사된 결과 Fluoranthene과 Benzo(a)pyrene의 독성이 강하게 나타난다. 온도실험에서는 동일한 유해물질을 가지고 실험을 하더라도 온도의 변화에 따라 급격한 독성의 차이가 나타날 수 있고, 유해물질간에도 온도에 따라서 나타나는 독성에 대한 특성이 다르게 나타났다. Benzo(a)Pyrene에 노출된 먹이는 요각류의 egg Production, hatching rate, fecal Pellet에 영향을 미치고 있으며, 특히 농도와 실험시간에 따른 부정적 영향들을 보였다.

• Proceedings of the KIEE Conference
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• 2001.07a
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• pp.47-50
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• 2001

Presently the Korean grounding system uses TN system, multi-grounding method with TT independent grounding method. Nevertheless TN system can't exist with TT system in the technological terms. If they coexist, it causes ground-fault circuit not to operate, and brings about different electrical potential rise by customer system. It brings about serious problems for safety. This paper aims for improving method of grounding system based on the technical analysis on instances in foreign countries and Korea. Almost standards and construction manner were apt to be internationalized after WTO/TBT agreement was concluded. The internal grounding systems should meet the international criteria and reliability for safety, and be provided with technologically impeccable standards.

• Proceedings of the KIEE Conference
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• 2005.07e
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• pp.112-114
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• 2005

It is obvious that electrical safety cannot be secured soley by the efforts from public sector including government. With the global trend of deregulation as WTO/TBT agreement comes into effect, foreign countries strive to minimize unnecessary and inefficient regulations in every field by sharing responsibilities with the privae sector to secure international competency in trade. To this same end, in this paper 2 level approach plan is suggested to pave the way to the self-security system in electrical field by introducing self-reliance safety system by stage for pre-service inspection on the electrical installations for private use based on product requirements in terms of performance.

• Journal of TMJ Balancing Medicine
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• v.12 no.1
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• pp.15-21
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• 2022

This case is witten for presenting the effect of the TMJ balancing therapy using the TMJ balancing appliance which normalizes the yin and yang balance of the brain-nervous system including the Meridian system. The balancing appliance was used in patient with cervical dystonia, and clinical outcome measurements were performed through clinical observations in specific movement and actions. The patient displayed positive changes after the treatment and the effect was well-maintained during the treatment period. For the more precise evaluation, clinical and biological studies of temporomandibular balancing therapy (TBT) are needed.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.05a
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• pp.492-493
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• 2002

• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.399-404
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• 2003

Aliphatic polyester, especially poly(butylene adipate)(PBA), is quite biodegradable and one of the most promising polymer materials to be commercialized. Bis(4-hydroxybutyl) adipate (BHBA) formation stage is the first principal process in the production of PBA from adipic acid (AA) and 1,4-butane diol (BD). In this study, we investigated for the effective production of Bis(4-hydroxybutyl) adipate (BHBA), effects of molar ratio of adipic acid (AA) to 1,4-butane diol (BD), catalyst (tetrabutyl titanate, TBT) concentration, and temperature on the reaction rate of esterification between AA and BD were investigated. Initial reaction rate of the esterification decreased with increasing molar ratio of AA to BD and reaction temperature, whereas reaction constant increased with increase in catalyst-concentration. Activation energy values for catalyzed and uncatalyzed esterifications were 198.5 and 94.8 kJ/mol, respectively.

• The Korean Journal of Malacology
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• v.20 no.1
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• pp.93-105
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• 2004

Arkshell clams, Scapharca broughtonii, are economically important edible bivalves and widely cultivated in the Southern coast of Korea. Recently, the production of S. broughtonii has been dramatically decreased and various reasons including chemical pollution were suspected to be related to the production declines. However, it remains unknown whether the chemical pollution levels of the surrounding environments were high enough for the biological and ecological disturbance for the population of S. broughtonii, because no systematic toxicological study using S. broughtonii has been conducted previously. In the present study, we exposed arkshell clams, S. broughtonii to various waterborne pollutants including heavy metals (Cd, Cu and Hg), ammonia and organotins (tributyltin and triphenyltin) to determine the effect concentrations of these pollutants for the survival of S. broughtonii for 20 days. The median lethal concentrations ($LC_50$) of S. broughtonii were 2.1 mg/l for Cd, 0.065 mg/l for Cu, 0.40 mg/l for Hg, 79.4 mg/l for total ammonia (1.9 mg/l for unionized ammonia), 0.5 ${\mu}$g/l for TBT, and 14${\mu}$g/l for TPhT. Lethal toxicity of the most pollutants increased with both exposure duration and concentration. The toxicity of TBT was greatest for S. broughtonii, followed by TPhT > Cu > Hg > Cd > ammonia. The sensitivities of S. broughtonii to heavy metals and TBT were comparable to those of other aquatic organisms, but they were relatively tolerable to ammonia. The environmental concentrations of the tested pollutants were compared with the effect concentrations of those for the survival of S. broughtonii to assess the potential risks of the pollutants in the field conditions.