• Journal of IKEEE
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• v.11 no.4
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• pp.152-157
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• 2007

AlGaN/GaN high electron mobility transistors (HEMTs) were fabricated and the effect of ${N_2}O$ plasma on the electrical characteristics of the devices was investigated. The HEMT exposed to ${N_2}O$ plasma formed by 40 W of RF power in a chamber with pressure of 20 mTorr at a temperature of $200^{\circ}C$, exhibited a reduction of gate leakage current from 246 nA to 1.2 pA by 10 seconds treatment. The current between the two isolated active regions reduced from 3 uA to 7 nA and the sheet resistance of the active layer was lowered also. The variations of electrical characteristics for HEMT were occurred within a short time expose of 10 seconds and the successive expose did not influence on the improvements of gate leakage characteristics and conductivity of the active region. The reduced leakage current level was not varied by successive $SiO_2$ deposition and its removal. The transconductnace and drain current of AlGaN/GaN HEMTs were increased also by the expose to the ${N_2}O$ plasma.

• Journal of dental hygiene science
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• v.8 no.1
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• pp.1-6
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• 2008

The purpose of this study was to analyze the reasons and mean age for tooth extraction among patients living in Busan city. The researcher observed 1,119 patients' teeth extracted due to dental caries, periodontal disease and other reasons. This study examined the reasons for tooth extraction by age, sex, and tooth-kind. The reasons for tooth extraction were dental caries, periodontal disease, eruption problems and others. The obtained results were as follows; 1. Among the reasons for tooth extraction, dental caries accounted for 25.9%, periodontal disease 56.5%. 2. Periodontal disease was the main reason for tooth extraction and continued throughout life irrespective of sex. However dental caries was remarkably increasing in those aged 30 years old and under. 3. In the extraction of permanent teeth, males outnumbered females while upper teeth did lower teeth. 4. Although the third molars were most extracted in all kinds of teeth, the main reasons for the extraction were eruption problem. 5. The mean age of the tooth extracted was 47.9 years in both sexes for the mandibular first molars and the mandibular first molars had the shortest life except third molars of total teeth. The mandibular canines had the longest life of total teeth. Because dental caries and periodontal disease are the main causes of tooth extraction in Korea, the dental health policy should be focused on the prevention and treatment of these two diseases in the government level.

• Korean journal of applied entomology
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• v.53 no.4
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• pp.479-483
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• 2014

The area of greenhouse horticulture has increased dramatically since the early 1990s in Korea. However, area per farmer still very small and diverse pest species occurs in greenhouse abundantly because of its protected condition. To manage pests, farmers use many pesticides frequently. Incessant and improper use of chemicals provoked pesticide resistance in pest and poisoning of farmers. In this study, we investigated the efficiencies of automatic dry fog sprayer for controlling two aphid species, Aphis gossypii and Myzus persicae, in greenhouse horticulture. When doors and side windows were completely closed in automatic dry fog sprayer treatment greenhouse, aphids were controlled similar level with conventional spraying method (percent control: 61.0~94.1%). However, when half of the doors and side windows of the greenhouse were opened, aphids were controlled poorly (percent control: 36.0~54.4%).

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.24-24
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• 2017

Heavy metals at toxic levels have the capability to interact with several vital cellular biomolecules such as nuclear proteins and DNA, leading to oxidative stress in plants. The present study was performed to explore the metal tolerance mechanism in Sorghum seedling. Morpho-physiological and metal ions uptake changes were observed prominently in the seedlings when the plants were subjected to different concentrations of $CuSO_4$ and $CdCl_2$. The observed morphological changes revealed that the plants treated with Cu and Cd displayed dramatically altered shoot lengths, fresh weights, and relative water content. In addition, the concentration of Cu and Cd was markedly increased by treatment with Cu and Cd, and the amount of interacting ions taken up by the shoots and roots was significantly and directly correlated with the applied level of Cu and Cd. Using the 2-DE method, a total of 24 and 21 differentially expressed protein spots from sorghum leaves and roots respectively, 33 protein spots from sorghum leaves under Cd stress were analyzed using MALDI-TOF/TOF MS. However, the over-expression of GAPDH plays a significant role in assisting Sorghum bicolor to attenuate the adverse effects of oxidative stress caused by Cu, and the proteins involved in resistance to stress helped the sorghum plants to tolerate high levels of Cu. Significant changes were absorbed in the levels of proteins known to be involved in carbohydrate metabolism, transcriptional regulation, translation and stress responses. In addition, the up-regulation of glutathione S-transferase and cytochrome P450 may play a significant role in Cd-related toxicity and stress responses. The results obtained from the present study may provide insights into the tolerance mechanism of seedling leaves and roots in Sorghum under heavy metal stress.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.571-575
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• 2014

'Dream Song' is a cultivar of Gypsophila paniculata developed by the Jeollabuk-do Agricultural Research & Extension Services in 2010 for cut-flower production. This hybrid was bred from 121 seedlings collected from an open-pollinated population of 'Gyp06-11'. It has novel morphological characteristics of upright plant type, lanceolate leaves, double florets with a few bright white-colored petals of obovate shape, truncate petal tips, and cup-shaped calyces. Furthermore 'Dream Song' has desirable cultivation characteristics including narrow branching angle, and moderate resistance to powdery mildew, thrips and leaf miners. Moreover it produces more primary branches, and longer internodes and flower stalks than reference cultivar 'Bristol Fairy' during summer cultivation in a subalpine area (500 m over the sea level). Flowering in 'Dream Song' is delayed by about 17 days as compared to 'Bristol Fairy'. 'Dream Song' produces normal flowers with 2 pistils and an average of 10.4 stamens, with fewer malformed flowers than 'Bristol Fairy'.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1995.10a
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• pp.160-164
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• 1995

정보통신 시스템의 고속/고밀도화 요구에 따라 개발되고 있는 ATM(Asynchronous Transfer Mode) 교환기 시스템은 팬을 이용한 강제대류냉각 방식의 채택과 시스템이 설치되는 장소에 따른 여러 환경조건에 의한 진동 문제가 발생될 수 있다. 시스템의 진동으로 인한 피해중 커넥터 접촉부에서 전기적 특성의 변화는 고속으로 전송되는 신호의 왜곡을 유발시킬 수 있어 시스템 개발시 이에 대한 충분한 연구 및 시험이 요구되고 있다. 진동환경에서 커넥터 접촉부는 접촉면의 상대운동으로 인한 접촉저항의 증가와 순간적인 신호전달 중단을 가져오게 되며, 특히 PCB/Connector Assembly에서 커넥터 접촉부는 PCB(Printed Circuit Board)의 장착 조건 및 동적 거동에 따라 전기적 특성이 변할 수 있다. 시스템에서 커넥터의 동적 거동을 이해하기 위해서는 PCB를 포함하는 시스템내 여러 요소의 동적 특성 이해와 복잡한 해석과정이 요구되며, 시스템 개발자는 진동 환경에서 이것의 시험 결과에 따라 커넥터의 사용을 결정해야 할 것이다. 커넥터의 전기적 특성 시험법은 IEC, EIA드 여러 국제 규격에 제시되어 있으며, 본 연구의 대상이 된 ATM교환기 시스템에서 PCB/Connector Assembly의 진동환경에서 접촉저항 측정과 관련된 접촉저항 임계치 및 측정법은 IEEE 규격 및 Bellcore 규격에 규정되어 있다. Bellcore에는 주어진 진동시험주기 전후에 IEC 규격의 LLCR(Low Level Contact Resistance) 측정회로를 이용한 측정법이 규정되어 있고, 냉각팬 및 주위 환경진동이 가해지는 동안의 영향에 대한 시험법은 규정되어 있지 않다. 본 연구에서는 한국통신의 전자장비 운용환경시험 조건의 진동에서 ATM 교환기 시스템에 사용되는 PCB/Connector Assembly 커넥터 접촉부의 접촉저항 변화와 PCB 진동에 의한 영향을 시험하였다.proach)등이 제시되었고 평면파 영역에 한하여 해서되어져 왔다. 본 논문에서는 분할 접근 방법(Segmentation Approach)을 이용하여 다공 요소로 이루어진 소음기를 해석하는데 적용하였다.로 성능 및 안정도에 영향을 미치므로 주의 깊게 선정해야 한다. 방법의 실질적인 적용에는 어려움이 있다. 본 연구에서는 기존의 방법들의 단점을 극복할 수 있는 새로운 회귀적 모우드 변수 규명 방법을 개발하였다. 이는 Fassois와 Lee가 ARMAX모델의 계수를 효율적으로 추정하기 위하여 개발한 뱉치방법인 Suboptimum Maximum Likelihood 방법[5]를 기초로 하여 개발하였다. 개발된 방법의 장점은 응답 신호에 유색잡음이 존재하여도 모우드 변수들을 항상 정확하게 구할 수 있으며, 또한 알고리즘의 안정성이 보장된 것이다.. 여기서는 실험실 수준의 평 판모델을 제작하고 실제 현장에서 이루어질 수 있는 진동제어 구조물에 대 한 동적실험 및 FRS를 수행하는 과정과 동일하게 따름으로써 실제 발생할 수 있는 오차나 error를 실험실내의 차원에서 파악하여 진동원을 있는 구조 물에 대한 진동제어기술을 보유하고자 한다. 이용한 해마의 부피측정은 해마경화증 환자의 진단에 있어 육안적인 MR 진단이 어려운 제한된 경우에만 실제적 도움을 줄 수 있는 보조적인 방법으로 생각된다.ofile whereas relaxivity at high field is not affected by τS. On the other hand, the change in τV does not affect low field profile but strongly in fluences on both inflection fie이 and the maximum relaxivity value. The results shows a fluences on both inflection field and the maximum relaxivity v

• Radiation Oncology Journal
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• v.30 no.3
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• pp.117-123
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• 2012

Purpose: Although anemia is considered to be a contributor to intra-tumoral hypoxia and tumor resistance to ionizing radiation in cancer patients, the impact of pretreatment anemia on local control after neoadjuvant concurrent chemoradiotherapy (NACRT) and surgery for rectal cancer remains unclear. Materials and Methods: We reviewed the records of 247 patients with locally advanced rectal cancer who were treated with NACRT followed by curative-intent surgery. Results: The patients with anemia before NACRT (36.0%, 89/247) achieved less pathologic complete response (pCR) than those without anemia (p = 0.012). The patients with pretreatment anemia had worse 3-year local control than those without pretreatment anemia (86.0% vs. 95.7%, p = 0.005). Multivariate analysis showed that pretreatment anemia (p = 0.035), pathologic tumor and nodal stage (p = 0.020 and 0.032, respectively) were independently significant factors for local control. Conclusion: Pretreatment anemia had negative impacts on pCR and local control among patients who underwent NACRT and surgery for rectal cancer. Strategies maintaining hemoglobin level within normal range could potentially be used to improve local control in rectal cancer patients.

• Korean journal of food and cookery science
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• v.31 no.2
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• pp.118-127
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• 2015

In this study, the effect of Cheonggukjang powder were investigated on the regulation of blood glucose and inflammatory in STZ-induced diabetic rats. The experimental diet used this study were three kinds of Cheonggukjang, which were soybean Cheonggukjang, Yakkong Cheonggukjang and black foods such as black rice, black sesame seeds, and sea tangle added Yakkong Cheonggukjang powder. The experimental animals were divided into 5 groups and fed experimental diets for 7 weeks; non-diabetes with normal diet group (C), diabetes with normal diet (DC), diabetes with soybean Cheonggukjang (DS), diabetes with Yakkong Cheonggukjang (DY), and diabetes with Yakkong black foods added Cheonggukjang (DYB). Blood glucose and insulin resistance of STZ-induced diabetic groups were were significantly higher than C group. But insulin levels and insulin secertory of STZ-induced diabetic groups were significantly lower than C group. However, supplementation of Yakkong or black foods added Yakkong Cheonggukjang were proven to regulation them. In diabetic group, free fatty acid level was significantly increased than C group, but this contents was significantly decreased supplementation of soybean Cheonggukjang. Leptin and adiponectin levels were significantly decreased in STZ-induced diabetic groups.

• Korean Journal of Social Welfare
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• v.37
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• pp.327-355
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• 1999

This study analyzes the relationship between NGOs and government assisting defecting North Korean residents and seeks a desirable model of a linkage between the two sectors. The factors used in this study for an analysis of the relationship between NGOs and government are frequency and direction of interaction between NGOs and government, government's acceptance or resistance of institutional pluralism. the degree of formality of the relationship, and the relative power balance in the relationship. Also, Coston's typology(l998) of NGO-government relationships is applied for the analysis. Results of the analysis indicates that, in resettlement assistance for defecting North Korean residents, Korean NGOs and government have a cooperative relationship at minimal level, which means that there is a low linkage, informal relationship, and asymmetrical power-relationship between the two sectors. Also, government's acceptance of institutional pluralism seems to be superficial and a tendency of one-way direction of interaction is identified. Based on the findings, this study suggests a more collaborative relationship or partnership between NGOs and the government to arrange more effective assistance programs and activities. Discussion of some controversial issues related to achieving the collaboration and suggestion of a possible model of linking government to the NGOs are followed in conclusion.

• Journal of Environmental Policy
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• v.11 no.3
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• pp.149-170
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• 2012

The United Nations Climate Change Conference, Durban 2011, ended on December 12, 2011, 36 hours over its schedule, delivering the Durban Package, which consisted of, inter alia, the extension of the period for Kyoto Protocol term and the launch of Ad-hoc working Group on the Durban Platform for Enhanced Action. Despite the positive progress made in Durban, the future of post-2012 climate regime still seems cloudy. Before the Durban conference, some of Annex I countries with emissions reduction commitment under the Kyoto Protocol's first commitment period openly declared their intention not to participate in the second one, reducing the effectiveness of Durban agreement. Parties to the conference have a long list of difficult issues disturbing the materialization of the new legal agreement in 2020 such as level of mitigation targets of individual countries and legal nature of their commitment. Given this uncertainty, the Korean government should reinforce its domestic climate policies rather than settling in the fact that it remains as a non-Annex I county party under the Durban Agreement due to the extension of the Kyoto Protocol period. Domestically, it needs to continue to raise the public awareness for rigorous climate policies to transit its economy to low carbon pathway which reduces the country's dependency on fossil fuel in the long term. It is also important to implement cost effective climate policies to cope with domestic resistance and international competitiveness. Internationally, its priority would be working for trust-building in the on-going negotiation meetings to encourage meaningful participation of all parties.