• 공업화학
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• 제7권5호
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• pp.813-822
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• 1996

온실효과에 주요한 기여를 하는 이산화탄소를 줄이기 위하여 새로운 형태의 고분자인 폴리(알킬렌 카보네이트)가 합성되어졌다. 이산화탄소와 여러 가지 에폭시드로부터 칼복시산의 아연염을 촉매로 하여 교대 공중합체가 만들어졌다. 중합체의 수 평균 분자량은 50,000 정도이면 중합 분산도는 5~10 정도로 비교적 넓은 분포를 갖는다. 이 중합체는 비 결정성이고, 투명한 물질로써 열분해가 쉽게 일어난다. 높은 온도와 불활성 분위기 하에서도 완벽한 분해가 일어나 탄소 잔류물을 남기지 않는 것으로 알려졌다. 간단한 에폭시드와의 공중합체의 물리적인 성질을 개선하기 위하여 입체 장애가 큰 에폭시드와의 삼원 공중합체도 만들 수 있다. 이러한 분해성을 이용하여 세라믹, 금속, 전자 산업용 바인더나 lost-foam casting에 활용이 검토되었다. 또한 포장용 필름이나 가소제로의 활용도 연구될 수 있을 것으로 기대된다.

• Transactions on Electrical and Electronic Materials
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• 제14권6호
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• pp.308-311
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• 2013

The effect of an electric field on the ac electrical treeing in various epoxy/reactive diluent systems was studied in a needle-plate electrode geometry. Diglycidyl ether of bisphenol A (DGEBA) type epoxy was used as a base resin, and 1,4-butanediol diglycidyl ether (BDGE) or polyglycol (PG) as a reactive diluent was introduced to the DGEBA system, in order to decrease the viscosity of the DGEBA epoxy system. BDGE was acted as a chain extender, and PG acted as a flexibilizer, after the curing reaction. To measure the treeing initiation time and the propagation rate, three constant alternating currents (ac) of 10, 13 and 15 kV/4.2 mm (60 Hz) were applied to the specimen, in a needle-plate electrode arrangement, at $30^{\circ}C$ of insulating oil bath. When 10 kV/4.2 mm (60 Hz) was applied, the treeing initiation time and the propagation rate in the DGEBA system were 356 min and $1.10{\times}10^{-3}$ mm/min, respectively, those in the DGEBA/BDGE system were 150 min and $1.14{\times}10^{-3}$ mm/min, respectively. Those in the DGEBA/PG system were 469 min and $1.05{\times}10^{-3}$ mm/min, respectively. As 15 kV/4.2 mm (60 Hz) was applied, the propagation rate in the DGEBA system was $5.41{\times}10^{-3}$ mm/min, and that in the DGEBA/PG system was $1.42{\times}10^{-3}$ mm/min. These values meant that PG could be used as a reactive diluent in the DGEBA system, without the deterioration of the insulation breakdown property.

• 대한한의학원전학회지
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• 제23권6호
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• pp.97-108
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• 2010

Salt is a vital inorganic substance to human body and is seasoning in food. It is an absolute alternating factor on fermented food. What's more, in the oriental medicine, it is widely used to raise the pharmacological effect as a component of a prescription when processing a medicine, and when taking the medicine. Though, Importance of salt is often unaware and it is not used in the right way. focusing on "東醫寶鑑 內景篇 Donguibogam-Naegyeong" I categorized the methods of salt's prescription, dose, processing, seasoning, etc. The contents were compared and studied as well. When salt is used as a medicine, It is used as a main medicine, complimentary(aid) medicine, Jjim-Jil(hot towel or bath etc), vomiting medicine and gargling water. when taking the salt water with other medicine, depending on the type of the medicine, boiled salt water, warm alcohol or salt water, mixing powder medicine with salt water etc The methods are diverse. The reason to process medicine with salt or salt water is to bring the pharmacological Qi(energy) down to increase remedial value. When processing a medicine, kneading dough with salt water and the case using food ingredient as medicine salt was used as seasoning. Kneaded mud with salt were used to cover medicine or on the outer surface. This proves that it prevents the dryness and helps the medicine cooked even. Like this, salt is vital and highly-valued medicine in the oriental medicine. learning the right method of using salt and if it were used properly It is considered that it would increase the Pharmacological effect.

• 교육시설 논문지
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• 제19권3호
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• pp.21-31
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• 2012

According to the decrease in birth rate and reduction of population in rural area, primary schools have brought about many problems for decrease of number of student, and environment of education have became deteriorated. Accordingly, primary schools be required improvement, and it should be altered placement of schools because it change number of student, distance and time of attending school, and formation of school zone are changed by alternating of human and physical environment. Merger and abolition of primary school is inevitable for change of placement standard to primary school and qualitative improvement of environment of education in rural area. This study suggests the effective space planning methods for unified school and appropriate utilization alternatives for closed school following after the merger and abolition of small rural schools. In doing so, it explores the present models of merger and abolition through analysis of all sort of actual condition and the possibilities for various utilizations of the abolished schools. It proposes a classroom-operation type fused the comprehensive class and departmental class system for merged primary schools in rural area. It also suggests the re-use methods of closed school facilities for students and community. Finally, it emphasizes that in order to success the policy of the merger and abolition of small schools, it be attributed to the social-cultural environment based on local residents and community and required provision of a variety of utilization plans reflecting local specifics and guarantee of local residents' participation and selection.

• 통상정보연구
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• 제11권2호
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• pp.343-367
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• 2009

This research is about global investment for managing the important position, what Korea is doing in World's main market. Considering there are some differences between developed countries' model and developing countries' model in doing direct overseas investment, they target to get political agreement and develop the new invest plan and strategy by understanding changes of Korean manufacturing companies in direct overseas investment between 2000 and 2007 and analyzing the change of yearly investment motivation factors and determining factors for investment. The result from this result let us know that company should develop their own idea for their competitive advantage by doing direct overseas investment with the existing theory which convinces the need of competitive advantage for investing overseas. I set actual model and analyze results from it with the considering that it is so important to get knowledge and information for globalizing companies to invest overseas and companies, which want to be world leading ones for their field through innovation and changes, need to have more active strategy. And, the overseas investment, which was already done in other countries, 1. Review its realities and tendency in terms of investing countries, investing industries, and its scale. 2. Set up an actual model, based on strategic combination of investing location select and determination of Korean manufacturing companies and yearly investing factor-effect analysis. 3. Analyze how the situational factors have influenced and what factors would be considered for direct overseas investment. From the analyzing result, even though it is fairly true that raising wage and getting resources, avoiding customs, and developing alternating industries for export had influenced at the beginning, overseas investing companies' policy will be influenced by the results from studying marketing-pursuit type, which emphasizes to manage trade income and outgo, keeping the balance in the black, ensuring raw materials, local producing and manufacturing by using low-wage people for local sale, and situation for changing investing tendency as service industry.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.551-555
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• 2010

Electrowetting is a versatile tool to handle tiny droplets and forms a backbone of digital microfluidics. Numerical analysis is necessary to fully understand the dynamics of electrowetting, especially in designing electrowetting-based devices, such as liquid lenses and reflective displays. We developed a numerical method to analyze the general contact-line problems, incorporating dynamic contact angle models. The method is based on the conservative level set method to capture the interface of two fluids without loss of mass. We applied the method to the analysis of spreading process of a sessile droplet for step input voltages and oscillation of the droplet for alternating input voltages in electrowetting. The result was compared with experimental data. It is shown that contact line friction significantly affects the contact line motion and the oscillation amplitude. The pinning process of contact line was well represented by including the hysteresis effect in the contact angle models. In level set method, in the mean time, material properties are made to change smoothly across an interface of two materials with different properties by introducing an interpolation or smoothing scheme. So far, the weighted arithmetic mean (WAM) method has been exclusively adopted in level set method, without complete assessment for its validity. We viscosity, thermal conductivity, electrical conductivity, and permittivity, can be an alternative. I.e., the WHM gives more accurate results than the WAM method in certain circumstances. The interpolation scheme should be selected considering various characteristics including type of property, ratio of property of two fluids, geometry of interface, and so on.

• 대한전자공학회논문지TC
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• 제46권12호
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• pp.59-64
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• 2009

본 논문을 통하여 Metamaterial 특성을 가지는 CRLH 전송선 구조를 이용하는 초광대역 대역저지 여파기의 설계를 제안한다. 기존에 사용되던 주기구조, 또는 다단의 CRLH 전송선이 아닌, 단일 쎌 구조를 이용하여 기존 반파장 공진기 기반의 여파기나 임피던스 교번형 저역통과 여파기 등에서 나타나는 길이가 길어지며 Chebyshev형의 낮은 스커트 특성을 가지는 단점을 보완하고, 기존에 없던 초소형 구조를 제시한다. 또한, 초광대역 저지특성을 위하여 계단형 임피던스 구조를 포함한 강결합 Metamaterial 구조를 제안하고 0차 공진을 이용한 초소형화 기법을 제시한다. 본 논문에서 제안하는 설계의 타당함은 3D EM 모의실험과 제작 및 측정을 통하여 검증하며 여파기의 크기를 ${\lambda}_g/10$ 이하로 감소, 12 GHz를 초과하는 차단대역, 통과대역의 0.7 dB 삽입손실 등의 주파수 영역 특성 결과를 보인다.

• Journal of Acupuncture Research
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• 제19권2호
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• pp.238-249
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• 2002

Facial palsy is commonly encountered disease in the clinic but bilateral facial palsy is known as rare disease. Type of facial nerve paralysis include unilateral, recurrent ipsilateral, recurrent alternating and bilateral simultaneous palsies. Among the types, the reported incidence of bilateral simultaneous palsy is 0.3~2% of facial paralysis patients. We experienced I case of patient with bilateral simultaneous facial palsy that was concluded as bilateral bell's palsy. Objective : The purpose of this paper is to report the patient with bilateral facial palsy, who improved by oriental medical treatment. Another purpose is to review the current literature and to differential diagnosis of bilateral facial paralysis. Methods and Results : The patient was treated by acupuncture, herb medication and self-massage on facial muscle for 14 weeks. House-brackmann grading score was improved into I/I (Rt/Lt) from IV/IV. Conclusion : Through reviewing some literatures and reports, It is concluded that bilateral facial palsy was related to many other disorders and more ominous than unilateral facial palsy. therefore, its work-up should include a complete neurologic assesment and thorough evaluation. also, we consider that bilateral Bell's palsy can improve by oriental medical treatments.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2003년도 춘계 학술발표회 논문집
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• pp.431-435
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• 2003

Because the Tissue Bound Tritium of food irradiates the organic tissues of a man during a longer time than the Tissue Free Water Tritium, we found the ratio of labile and bound hydrogen, which is the direct source of TBT concentration, in grain such as rice and barley. Tissue free water was extracted from rice and barley sampled, adjacent to Wolsung nuclear power plants of CANDU type, by freeze-drying. Tissue bound water was taken from some of the dried samples by high-pressure combustion. The other of the samples was washed by tritium-free water for 2-3 hours, and dried again by freeze-drying. Tissue bound water was taken again from some of the second dried samples by the combustion. The extracted tissue free and bound waters were distilled and TFWT and TBT concentrations of them were counted by a liquid scintillation counter. Through alternating washing, drying and combustion until the concentration of TBT would be constant, the tritium concentration existing as bound hydrogen was found. The ratios of labile and bound hydrogen of rice and barley were determined by TR concentration, initial TBT concentration and bound tritium concentration. The ratios of bound hydrogen of rice and barley were 0.55, 0.60 relatively.

• Applied Microscopy
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• 제32권1호
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• pp.39-44
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• 2002

한국어류의 수정란 난막 미세구조를 분류체계에 따른 체계화 작업의 일환으로 난문의 유무, 난막의 표면 및 단면구조를 밝힘으로써 계통분류학적 기초자료를 제시하고자 경골어류, 구굴무치과에 속하는 얼룩동사리의 수정란을 실험재료로 하여 주사전자현미경과 투과전자현미경을 이용하여 관찰하였다. 수정란은 부착성 및 침성란으로 장타원형이었으며 동물극쪽에 부착사가 부착되어 있었다. 난황낭 내에는 많은 유적들이 있었으며, 난막 표면은 pore cannal들이 분포하고, 난문은 관찰되지 않았다. 난막은 두 층으로 구성되어 있었는데 외층은 전자밀도가 높은 비부착성이었으며, 내층은 전자밀도가 서로 다른 7층으로 구성되어 있었다. 이상과 같이 얼룩동사리 수정란 난막의 미세구조적 특징은 얼룩동사리의 수정란이 가지는 독특한 형태학적 형질로서 종을 분류하는데 사용될 수 있을 것으로 사료된다.