• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.291.2-291.2
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• 2016

3D semiconductor material of silicon that is used throughout the semiconductor industry currently faces a physical limitation of the development of semiconductor process technology. The research into the next generation of nano-semiconductor materials such as semiconductor properties superior to replace silicon in order to overcome the physical limitations, such as the 2-dimensional graphene material in 2D transition-metal dichalcogenide (TMD) has been researched. In particular, 2D TMD doping without severely damage of crystal structure is required different conventional methods such as ion implantation in 3D semiconductor device. Here, we study a p-type doping technique on tungsten diselenide (WSe2) for p-channel 2D transistors by adjusting the concentration of hydrochloric acid through Raman spectroscopy and electrical/optical measurements. Where the performance parameters of WSe2 - based electronic device can be properly designed or optimized. (on currents increasing and threshold voltage positive shift.) We expect that our p-doping method will make it possible to successfully integrate future layered semiconductor devices.

• 대한전자공학회논문지
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• 제11권3호
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• pp.22-26
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• 1974

The effects of anisotropic mechanical stress applied normal to the surface of p-n junctions have been investigated. As the stress increased, the breakdown voltage was decreased and the breakdown mode became softer. Within a certain limitation in the applied stress, the above phenomena werw reversibbe, though relaxation and hysteresis phenomena were observed. The time constant of relaxation depended upon the shape of the stressing tip, but for the given tip and device a unique time constant was obtained. The stress.dependence of breakdown voltage showed a good linearity up to about 3.0${\times}10^4$ kgw/$\textrm{cm}^2$, when the flat tip of radius 15$\mu$ was used, and the temperatere-dependence of breakdown voltage under the stress also showed a good linearity in the temperature range of 100 to $300^{\circ}K$.

• Journal of Microbiology and Biotechnology
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• 제7권6호
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• pp.391-396
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• 1997

Two series of carbon sources, linear primary $C_1$~$C_9$ alcohols and linear $C_2$~$C_{10}$ monocarboxylic acids were tested for PHA synthesis in Paracoccus denitrificans. The results showed that the growth-associated synthesis of PHA could be referred only to the carbon sources with odd number of carbon except methanol. For all carbon sources with even number of carbon, nitrogen limitation was required to induce PHA synthesis in P. denitrificans. Poly(3-hydroxyvalerate)[P(3HV)] homopolymer was synthesized from $C_5$, $C_7$, and $C_9$ while growing in the presence of nitrogen, but the nitrogen depletion in the later growth period incorporated 3-hydroxybutyrate(3HB) unit into the polymer chain. The optimum C/N ratio for P(3HV) homopolymer production was found to be 10 when the strain was grown on 10 ml/l of valeric acid for 96 h. P. denitrificans synthesized P(3HB-co-3HV) copolymers from n-hexanoic and n-octanoic acid. The microstructural characterics of the P(3HB-co-3HV) copolymer from n-propanol was investigated using $^13C$-nuclear magnetic resonance spectroscopy, showing a structural heterogeneity.

• Journal of Ginseng Research
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• 제20권4호
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• pp.556-557
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• 1996

Ginseng (Panax ginseng) has been used as a tonic drug in Chinese Traditional Medicine for two thousand years. It is believed to be significantly beneficial for human health. During the past 20 years. due to the modern chemical, biological and pharmacological technology. the ginseng research of China has been developed rapidly Major-work has been carried out by many laboratories in beijing. shanghai and shonzhen, etc Since most of the research works were supported by pharmacological companies. Many interesting papers sometimes are of confidential limitation. It is not easy to bind those papers in common library. To make a comprehensive review of ginseng is very difficult and reluctant.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.339-340
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• 2007

Gradient system에 spiral waveform 입력을 가하면 Hardware limitation에 의하여 만들어지는 gradient fields에 Transient time delay가 발생한다. 이를 보상하기 위하여, Gradient system을 R-L-C 회로로 모델링하여 재구성에 필요한 k-space trajectory를 보정하여 개선된 image를 획득하였다.

• 대한구순구개열학회지
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• 제7권2호
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• pp.133-139
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• 2004

Congenital bilateral idiopathic hyperplasia of the coronoid processes presents with limited mouth-opening without visible maxillofacial deformity or temporomandibular joint dysfunction / disorder. According to Blanchard et al and McLoughlin et al, it was lnitially described in 1853 by Langenbeck, and the first cases were reported by Holmes in 1956. Since then, there have been regular reports of a certain number of cases. In 1995, McLoughlin et al recorded 79 published cases of bilateral hyperplasia of the coronoid processes. Among them, Fabie et al have found only 3 published cases relating to children younger than 8 years, and have presented the first case of objectively diagnosed restricted mouth opening from birth by pediatricians. Authors have experienced 2 child patients with mouth opening limitation who was diagnosed congenital bilateral idiopathic hyperplasia of the coronoid processes without any other TNJ morphology in Dept of Oral and Maxillofacial surgery, Seoul National University Dental Hospital in 2004. Coronoidectomy was performed and postoperative active mouth opening exercise is indicated. Authors report 2 cases of congenital bilateial idiopathic hypeiplasia of the coronoid processes with literature liview.

• 한국수산과학회지
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• 제35권5호
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• pp.455-461
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• 2002

1999년 3월부터 2001년 10월까지 섬진강 하구역에서 영양염의 DIN/DIP 비와 생물검정실험을 이용하여 식물플랑크톤 성장을 제한하는 영양염을 파악$\cdot$비교하였다. 조사기간 동안 용존무기질소와 인산 인의 비는 평균 14.7$\~$681.1의 범위로, 조사시작 지점인 난초도 주변 해역을 제외한 25 psu 이하 염분역과 엽록소 a의 농도가 매우 높았던 구간에서는 계절에 관계없이 N/P 비가 16 이상으로 매우 높아 식물플랑크톤의 성장을 조절하는 제한 영양염은 인산 인인 것으로 판단된다. 반면, 약 25 psu 이상의 염분역인 난초도 주변 해역은 광양만으로부터 공급되는 인산 인의 영향으로 인해 DIN/DIP 비는 16 이하로 낮아, 용존무기질소가 식물플랑크톤의 성장을 제한하는 것으로 판단된다. 섬진강 하구역에서의 DIN/DIP 비의 변화양상은 인산 인의 공급양상, 즉 육상으로부터 의 낮은 공급 및 광양만으로 부터의 높은 공급 그리고 시$\cdot$공간적인 식물플랑크톤의 성장에 의해 주로 영향을 받는 것으로 판단된다. Skeletonema costatum 및 nalassiosira rotula와 현장 식물플랑크톤을 이용한 생물검정실험 결과는 인산 인이 첨가된 배지에서 성장이 상대적으로 높게 나타나, 섬진강 하구역에서 식물플랑크톤을 조절하는 제한영양염은 인산 인인 것으로 검증되었다. S. costatum은 타종에 비해 염분 적응이 빠르고, 인산 인에 대해 반응이 크게 나타나, 섬진강 하구역에서 가을철에 우점율 $90\%$ 이상의 costatum bloom이 발생되는 주요 원인이었을 것으로 추측된다 현장식물플랑크톤을 이용한 생물검정실험에서는 배양시작 초기에 미량금속 첨가계에서 비교적 빠른 성장을 보였으며, 20일 이후에 는 인산 인 첨가계에서 월등한 성장을 보였다. 이는 주변 해수의 영양염 분석과 식물플랑크톤 현존량만으로는 판단하기 어려운, 영양염 이외의 미량금속 그리고 비타민 등의 성장제한 요인에 대한 정보를 얻을 수 있다는 것을 시사해 준다.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2001년도 추계학술대회
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• pp.113-120
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• 2001

The production of microcystins from Microcystis aeruginosa was investigated in a P-limited continuous culture and a batch culture. The microcystin content of M aeruginosa was higher at a lower $\mu$, whereas the microcystin (MC)-producing rate was linearly proportional to $\mu$. The ratios of the MC-producing rate to the C-fixation rate were higher at a lower $\mu$. Consequently, increases in the microcystin content per dry weight along with the production of the more toxic form, MC-LR, were both observed under more P-limited conditions. The microcystin content of M. aeruginosa exhibited a high correlation with the total N content regardless of N-fixed or P-fixed culture. The microcystin concentration was investigated from spring to autumn in 1999 in the Daechung Reservoir, Korea. The dominant species in the algal blooming season was Microcystis. When the microcystin concentration exceeded about 100 ng $1^{-1}$ the ratio of particulate to dissolved total nitrogen (TN) or total phosphorus (TP) interestingly converged at a value of 0.6. The microcystin concentration was lower than 50 ng $1^{-1}$ at a particulate N:P ratio below 8, whereas the microcystin concentration varied quite substantially from 50 ng $1^{-1}$ to 250 ng $1^{-1}$ at a particulate N:P ratio> 8.

• 통상정보연구
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• 제6권3호
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• pp.63-79
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• 2004

Peer-to-peer(P2P) has potential strength and possible factors which enable it to develop toward a new business by supplementing the limitation of the existing central server-type network. In various business sectors, various attempts have already been made to apply P2P. The computing power which was possible to be formed through peer-to-peer networking will become a powerful tools for expanding toward new business area depending the utilization methods by sector. Although the technology-centric P2P concept is a major interest now, its development direction will head toward service-centric P2P concept for satisfying desires of end-users(individual peers) for reliable contents and improving their purchasing convenience. But the solution requisites should be solved for the efficient application of P2P to business such as the establishment of and supplement for the industrial standard and legal system for P2P, the enhancement of peers recognition of P2P. Presently e-commerce using P2P is being implemented by a few enterprises locally by means of B2C. But if many enterprises enter this type of e-commerce, and the standardization of peer programmes, goods and documents is made, it will be able to be extended to B2B. Also it seems that it can be utilized in international transactions as well as in domestic transactions. So there is much room for the application of P2P to be extended further. Also there has been presented the necessity for related industries to support their work with theories and for academic studies to be made actively to set the direction of its development. It is hoped that multi-angled and in-depth studies on the utilization of P2P and various attempts to application of it to business be made on the basis of this study. For the development of P2P, continuous study and attempts are needed. The field of P2Ps application is very large and it will become a powerful tool, depending upon its application methods.

• Imaging Science in Dentistry
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• 제34권2호
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• pp.91-97
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• 2004

Purpose : This study was performed to evaluate the diagnostic value of both planar and SPECT imagings by comparing the results with the clinical and other imaging modalities findings. Materials and Methods: A total of 578 joints with TMJ complaints were examined using planar scintigraphy and SPECT. The planar scintigraphy and SPECT findings were analyzed and compared to the clinical findings of pain, clicking, crepitus and limitation of mouth opening. Moreover we compared the accuracy of the planar scintigraphy and SPECT methods with the one of the panoramic, transcranial, tomographic and MR imaging methods. Results: The planar scintigraphy and SPECT methods showed a high sensitivity of 0.76-0.84 and low specificity of 0.25-0.45 toward the clinical findings: pain, clicking, crepitus and mouth opening restriction. Simple radionuclide uptake ratio was high in each group of patients with pain, crepitus, limitation of mouth opening (p < 0.05) complaints, in each group with positive bone changes on panoramic, transcranial or tomographic images, and in disc displaced group. Conclusion: Although both planar and SPECT imagings have limited specificity, these techniques are sensitive for detection of internal derangement of the TMJ.