Electrical Characteristics of AlxGa1-xN/GaN Heterostructure withIsoelectronic Al-Doped Channel for HFET Application

이정희,Jae-Hee Park,Jae-Hoon Lee,Jae-Seung Lee,Jong-Wook Kim,Kye-Seok Lee,Sung-Bum Bae,Sung-Ho Hahm 한국물리학회 2003 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.42 No.III

Based on investigating the effects of isoelectronic Al-doping on GaN film, a new layer structure is proposed for a heterostructure field effect transistor (HFET) including an isoelectronic Al-doped channel. The electron mobility measured at 77 (300) K significantly increased from 145 (130) cm$^2$/V$\cdot$s in the undoped sample to 823 (440) cm$^2$/V$\cdot$s in the Al-doped sample grown with a trimethylaluminum flow rate of 3 $\mu$mol /min, while maintaining the background doping concentration below $\sim$ 6 $\times$ 10$^{16}$ cm$^{-3}$. Two-dimensional electron gas mobilities of 1690 and 9280 cm$^2$/Vs were measured for a 25-nm Al$_{0.3}$Ga$_{0.7}$N/1-nm AlN/70-nm Al-doped channel/GaN heterostucture at 300 and 77 K, respectively. The improved results are explained based on a decrease in the compensating acceptors or other defects associated with the formation of screw dislocation due to the incorporation of Al in the channel layer, plus a decrease in the alloy disorder scattering in the heterostructure based on introducing a binary thin AlN layer between the Al$_{0.3}$Ga$_{0.7}$N and Al-doped channel layers.

세계화와 상호공존의 시민정신: 하퍼 리의 『앵무새 죽이기』

이정희 ( Chung Hee Lee ) 한국현대영미소설학회 2004 현대영미소설 Vol.11 No.1

치매의 원인과 증상

이정희,Lee, Jeong-Hui 한국건강관리협회 1995 건강소식 Vol.19 No.3

초산납이 생쥐 간뇌의 미세구조 및 Catecholamine 대사에 미치는 영향

이정희,유창규,최임순,Lee, Jung-Hee,Yoo, Chang-Kyu,Choe, Rim-Soon 한국현미경학회 1988 Applied microscopy Vol.18 No.2

The present experiment was performed to investigate the acute and subacute effect of lead acetate on ultrastructural and biochemical changes in mouse diencephalon. In acute case, mouse were peritoneally injected with lead acetate at a dose of 0.26 mmole/kg body weight, and after treatment, mouse were sacrificed at time intervals of 12, 24, 48, and 96 hours. In subacute case, mouse were injected at doses of 0.07 mmoie/kg B. W. and 0.13 mmole/kg B.W. once at two days, and after treatment, mouse wee sacrificed at 1 week, 2 weeks, and 3 weeks. It was observed that after acute treatment, changes composed of increased monoamine oxidase activity, $Na^{+}-K^{+}$ ATPase activity, decreased $Mg^{2+}$-APTase activity, wrinkled myelin, swollen Golgi apparatus and more dense synaptic vesicle in nerve terminal. After subacute treatment, decreased monoamine oxidase activity, increased $Mg^{2+}$-ATPase, $Na^{+}-K^{+}$ ATPase, lose of myelin, uneven mitochondrial distribution, synaptic vesicular density and edema, but at a higher dose the effect was more severe. Therefore, lead acetate caused abnormal change of diencephalon, and at a subacute, it appears metal accumulative toxicity.

얼굴 특징점 추적 및 움직임 측정도구

이정희,이영희,차의영,Lee, Jeong-Hee,Lee, Young-Hee,Cha, Eui-Young 대한임베디드공학회 2011 대한임베디드공학회논문지 Vol.6 No.5

This paper proposes facial feature tracking based on modified ART2 neural networks. And we also suggest new measurement devices such as 'Persistence Exponent' and 'Moving Space Exponent' for the criterion of input vector which consists features. The proposed methods have been applied to classify 48 students by 2-class (ADHD positive, ADHD negative). The results of the experiment have shown that the proposed methods are effective for ADHD Behavior Pattern Classification based on the Image Processing.

백서의 아킬레스 건 봉합 후 Hyaluronate-Carboxymethyl cellulose가 조직 유착에 미치는 영향

이정희,정비오,김교영,Lee, Jung-Hee,Jeong, Bi-O,Kim, Gou-Young 대한족부족관절학회 2009 대한족부족관절학회지 Vol.13 No.1

Purpose: The purpose of this study was to evaluate the effect of Sodium hyaluronate-Sodium carboxymethyl cellulose (HA-CMC) on tissue adhesion after tenorrhapy in tenotomized Achilles tendon of the Sprague-Dawley rat. Materials and Methods: Twenty-eight legs of 14 Sprague-Dawley rat were used in study. After tenotomy of the Achilles tendons, tenorrhaphies were performed. Simple tenorrhaphy without any other procedures were performed on the left Achilles tendons (control group), and additional HA-CMC injections were done prior to the tenorrhaphy on the right Achilles tendons (HA-CMC group). Gross and histological examinations were made to identify differences between the two groups, 1, 2, 6, 8, 10, 12 and 14 weeks respectively. Results: Distinct decrease in granulation tissues and adhesions were seen in the HA-CMC group during gross inspection at 6 and 8 week after the operation. On histological analysis of the HA-CMC group, although increased infiltrations of inflammation cells were observed during 1 week, less adhesion were seen at 6, 8 and 10 weeks after the operation. In HA-CMC group, superior healing processes were seen at 6, 8 and 10 weeks and less fibrotic changes, compared to control group, were seen at 2 and 6 weeks. Conclusion: Prevention of adjacent tissue adhesion was made possible through decrease in collagen deposition and fibrosis by injecting HA-CMC before tenorrhaphy of Achilles tendon. Also, histologically faster healing process of the collagen fibers within the Achilles tendon was observed.

통증완화를 위해 비파엽 찜질을 병행한 암환자 6례에 대한 증례보고

이정희,장보형,권혁성,권오섭,Lee Jung-Hee,Jang Bo-Hyoung,Kweon Hyug-Sung,Kweon O-Seob 대한한방내과학회 2003 大韓韓方內科學會誌 Vol.24 No.4

Objective: The purpose of this study is to see whether pain in cancer patients is decreased by Eriobotryae Folium Fomentation. Methods: We examined the change in pain among six cancer patients, prescribing Eriobotryae Folium Fomentation. As for evaluating methods, we used the case history of pain, the direct evaluation of pain, the indirect evaluation of pain. The direct evaluation of pain is subdivided by the language expression, the non-language expression, and Visual analog scale(VAS). The indirect evaluation of pain is subdivided by the condition of walking, mood and the condition of sleep. Results: After two weeks, any remarkable pain decrease is not observed in both of the direct evaluation and indirect evaluation.

In-situ 성장법에 의한 ZIF-8 분리막 합성 및 H₂/CO₂ 분리 특성

이정희,유성종,김진수,Lee, Jeong Hee,Yoo, Sung Jong,Kim, Jinsoo 한국막학회 2018 멤브레인 Vol.28 No.2

ZIFs (Zeolitic imdazolate frameworks)은 높은 화학적 열적 안정성, 높은 비표면적과 조절 가능한 기공구조로 최근 분리막 소재로 큰 관심을 받고 있다. 본 연구에서는 두 가지 종류의 다공성 지지체(${\alpha}$-alumina 및 YSZ)를 사용하여 in situ 성장법으로 ZIF-8 분리막을 합성하고, $H_2/CO_2$ 기체 투과 특성을 조사하였다. 결함 없는 ZIF-8층을 합성하는데 있어, 기공이 작은 YSZ 지지체는 ${\alpha}$-alumina 지지체 보다 더 적은 시간이 요구되었다. 합성시간이 3 h인 경우, ${\alpha}$-alumina 및 YSZ 지지체위에 형성된 ZIF-8 분리막은 약 10 정도의 $H_2/CO_2$ 선택도를 보였다. ZIFs (Zeolitic imdazolate frameworks) have attracted great attention as membrane materials in recent years due to their high chemical and thermal stability, high specific surface area and adjustable pore structure. In this study, ZIF-8 membranes were synthesized by in-situ growth method on two different support materials (${\alpha}$-alumina and YSZ) and their $H_2/CO_2$ gas permeation characteristics were investigated. In order to synthesize defect-free ZIF-8 layer, YSZ support required less synthesis time than ${\alpha}$-alumina support due to smaller pore size. After in-situ growth for 3 h, ZIF-8 membranes prepared on both YSZ and ${\alpha}$-alumina supports showed $H_2/CO_2$ selectivity of about 10.

음악요법이 상태불안과 활력징후에 미치는 효과

이정희,정현택,조은미,황옥남,Lee, Jung-Hee,Jung, Hyun-Teak,Kim, Eun-Mi,Hwang, Ok-Nam 한국재활간호학회 2006 재활간호학회지 Vol.9 No.1

Purpose: This study has tried to find out the effects of music therapy on anxiety of surgery patients during operation under regional anesthesia. In order to find out the effects, this research design was used nonequivalent control group non-synchronized design. Method: The subjects were the sixty inpatients under regional anesthesia in K hospital. They were assigned to two groups, thirty to the experimental group and thirty to control group. The data were collected using the Visual Analogue Scale(VAS) for State Anxiety and vital sign. The Experimental group received favorite music of the 4 different genre. The control group were inserted ear plug during operation. Data were analyzed by $X^2$-test, T-test, ANOVA and Repeated Measured ANOVA of the SPSS WIN (12.0) version program. Results: 1) Hypothesis 1: The hypothesis "that the figure for state anxiety of the experimental group provided with music therapy would be lower than that of the control group" was confirmed(F=0.27, P=0.01). 2) Hypothesis 2 : Three subordinating hypotheses were established in order to verify the hypothesis "that the figures for vital sings of the experimental group provided with such as music therapy would be lower than those of the control group." were rejected. Conclusion: Music therapy can be regarded as an effective nursing intervention that relieves operative anxiety of surgical patients under regional anesthesia.

5·18 사적지 기념공원화 계획 - 국군광주병원과 505보안부대 옛터를 대상으로 -

이정희,윤영조,Lee, Jeong-Hee,Yun, Young-Jo 한국조경학회 2019 韓國造景學會誌 Vol.47 No.5

본 연구는 5.18민주화운동 이후 사적지로 지정되었던 국군광주병원과 505보안부대 옛터를 대상으로 역사적 사실을 바탕으로 한 시대적 특성을 공간설계 개념으로 설정해 기념공원화 계획안을 제시하였다. 광주광역시는 5.18사적지인 국군광주병원과 505보안부대 옛터를 5.18기념사업의 일환으로 공원화하고자 도시공원 조성계획을 수립하고, 역사에 대한 기억의 공간으로만 보존해왔던 대상지를 5.18민주화운동의 역사적 가치를 함양함과 동시에 시민 삶에 활력을 주는 공원으로 단계적 조성계획을 추진하고 있다. 결과적으로 5.18사적지의 공동체적 가치가 현대적으로 계승될 수 있도록 사회적 합의를 통해 단계별 계획, 조성과정의 틀을 설정하고, 상처의 치유, 역사의 기억을 담아내는 계획을 하고자 함이다. 계획안에서 사적지의 공원화와 관련된 선행연구 및 계획사례 분석을 통해 공간 활용을 위한 문제 해결적 접근방법을 제시하였고, 대상지가 갖고 있는 장소적 가치를 탐색함과 동시에 공원의 계획개념을 유지하면서 역사적 사실에 대한 시대적 특성을 담아내는 공간 활용 전략과 세부내용을 서술하였다. 연구의 결과로 국군광주병원 사적지는 5.18민주화운동을 통해 남겨진 상처에 대한 치유의 문제를 지역사회가 주체적으로 해결할 수 있도록 과거의 역사적 기억과 치유의 공원으로 계획하되, 기존 자연환경을 활용한 치유의 숲 개념을 제시하였고, 505보안부대 옛터 사적지는 5.18기억공동체의 확장과 지속성을 강화하는 측면에서 미래 세대인 어린이와 청소년이 공감할 수 있는 역사 체험 배움의 공간개념으로 계획하였다. 사적지를 활용한 기념공원화 계획은 계획 단계에서 시민, 관련단체, 전문가를 아우르는 사회적 공감대의 형성이 선결요건으로 작용하며, 장소성 재현을 위한 구성원들의 사회적 합의가 공간활용 방향 설정에 중요한 계획적 요소로 작용할 수 있다. 본 연구를 통해 5.18사적지에 역사적 가치를 담는 기념공원으로 환원하는 데 기여하고, 과거 역사에 대한 상처와 기억을 치유하는 장소를 넘어 도시와 시민의 삶에 활력을 주며, 미래 세대와의 공유할 수 있는 방향성을 제시한 것에 대한 의의가 있다. This study presents a plan for a memorial park that respects the characteristics based on the historical facts for the concept of space of the Gwangju Hospital of Korea Army and the location of the 505 Security Forces, which were designated as historic sites after the 5-18 Democratization Movement. The Gwangju Metropolitan City as it is the location of the 5-18 historic sites, is taking part in the 5-18 Memorial Project, and plans to establish a city park recognizing the historic site of the 5-18 Democratization Movement, which has been preserved only as a memory space to this point. The park is promoting a phased development plan. This study suggests that the 5-18 historic sites can be modernized and that social consensus can establish the framework of the step-by-step planning and composition process to ensure the plans for the space heals wounds while preserving the history. In this paper, we propose a solution to a problem. We solve the approach for space utilization through an analysis of precedent research and planning cases related to park planning at historical sites. In addition to exploring the value of the site, we also describe the space utilization strategy that covers the historical characteristics and facts while maintaining the concept of park planning. As a result of the research, the historic site of the Gwangju Hospital of Korea Army is planned as a park of historical memory and healing in order to solve the problems left behind by the 5-18 Democratization Movement. The historic site of the 505 Security Forces was selected as an area for historical experiences and a place for learning that can be sympathized with by future generations of children and adolescents in terms of expanding and sustaining the memory of the 5-18 Democratization Movement. In the planning stage, the historical sites suggested the direction of space utilization for representation as did the social consensus of citizens, related groups, and specialists. Through this study, we will contribute to construction of a memorial park containing historical values in from 5-18 historic sites. It is meaningful to suggest a direction that can revitalize the life of the city as well as its citizen and can share with the history with future generations beyond being a place to heal wounds and keep alive the memory of the past.