• Journal of the Microelectronics and Packaging Society
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• v.21 no.4
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• pp.1-13
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• 2014

The paper gives an overview of the concepts, basic requirements, and trends regarding packaging technologies of power modules in hybrid (HEV) and electric vehicles (EV). Power electronics is gaining more and more importance in the automotive sector due to the slow but steady progress of introducing partially or even fully electric powered vehicles. The demands for power electronic devices and systems are manifold, and concerns besides aspects such as energy efficiency, cooling and costs especially robustness and lifetime issues. Higher operation temperatures and the current density increase of new IGBT (Insulated Gate Bipolar Transistor) generations make it more and more complicated to meet the quality requirements for power electronic modules. Especially the increasing heat dissipation inside the silicon (Si) leads to maximum operation temperatures of nearly $200^{\circ}C$. As a result new packaging technologies are needed to face the demands of power modules in the future. Wide-band gap (WBG) semiconductors such as silicon carbide (SiC) or gallium nitride (GaN) have the potential to considerably enhance the energy efficiency and to reduce the weight of power electronic systems in EVs due to their improved electrical and thermal properties in comparison to Si based solutions. In this paper, we will introduce various package materials, advanced packaging technologies, heat dissipation and thermal management of advanced power modules with extended reliability for EV applications. In addition, SiC and GaN based WBG power modules will be introduced.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.12
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• pp.2361-2367
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• 2011

In this paper survey and analysis of recent trends in noise barriers and noise measurements and assessments were conducted for providing design basis of ANC barriers. Looking at the results, transparent barrier(glass) has received the most attention in domestic and foreign countries, because it has a harmony with the surrounding environment and easy installation in a small space. For optimal barrier design using computer simulation, reliability of simulation has been verified and classified into 5 groups, according to barrier's upper cross section. Evaluation results of barrier's performance and design using computer simulation are as follows : In the case of the "B-type" barrier, it has improved maximum 2.5dB(A) at each point(R1~R6) and have a good workability. Therefore, "B-type" Barriers applied to the next active noise barrier system will be possible.

• Electronics and Telecommunications Trends
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• v.29 no.2
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• pp.33-41
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• 2014

본고에서는 한국을 비롯하여 미국, 일본, 유럽의 최근 빅데이터 특허시장을 분석하였다. 분석결과 빅데이터 특허시장은 미국이 세계시장을 독과점하는 구조로 나타났다. 전 세계적으로 가장 활발한 특허 활동을 전개하고 있는 미국 특허를 대상으로 빅데이터 연구개발 트렌드를 조망해 보면 과거에는 다수 기업들에 의하여 많은 특허출원이 이루어지는 경향을 보였으나, 최근 들어 기존 기업들 간의 경쟁이 심화되면서 대기업 위주로 특허출원시장이 재편되어 가는 경향을 보이고 있다. 한편 과거에는 데이터 분석 및 처리기술에 많은 특허출원이 이루어졌으나 최근에는 데이터 운영 및 관리기술로 옮겨가는 것으로 조사되었으며, 특허출원 건수도 과거에 비하여 대폭 증가하고 있는 경향을 보이고 있다. 우리나라의 경우 실시간 처리기술, 저장기술, 표현기술은 상대적으로 높은 출원 점유율을 보이고 있으나, 데이터 수집 및 분석기술은 상대적으로 점유율이 낮게 나타나 관련 기술 강화를 위한 대책 마련이 시급한 것으로 조사되었다. 정부는 이를 위하여 데이터 사이언티스트 양성을 위한 정책적 지원을 확대할 필요가 있다.

• Electronics and Telecommunications Trends
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• v.19 no.4 s.88
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• pp.135-141
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• 2004

본 논문에서는 국내 무선설비규칙의 불요발사 규정과 관련하여 2003년도 세계전파통신회의(World Radiocommunication Conference-03)의 의제 중 하나인 불요발사에 관한 전파규칙의 내용을 소개한다. 최근 ITU-R은 WRC-03 전파규칙의 불요발사 규정에서 스퓨리어스 발사의 측정기준을 위하여 대역외영역과 스퓨리어스영역의 개념을 새롭게 정의한 후 두 영역 사이의 경계기준을 정하였다. 따라서 본 논문에서는 ITU-R의 불요발사 영역개념과 경계기준을 분석하고, 이를 바탕으로 무선설비규칙 제5조 스퓨리어스발사의 허용치에 관한 개정의견을 제시하였다.

• Electronics and Telecommunications Trends
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• v.17 no.5 s.77
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• pp.15-25
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• 2002

사용자 요구의 다양화와 그에 따른 트래픽 증가 등 현재의 IMT-2000 기반에서 수용할 수 없는 보다 복잡한 이동 멀티미디어 환경이 도래하고 있다. 이러한 이동 멀티미디어 서비스를 원활히 제공하기 위해 ITU-R을 중심으로 한 전세계 이동통신 업계는 이미 4G 시스템 규격 및 개발에 상당한 진전을 보이고 있다. 이에 따라 ETRI도 지난 2002년 1월부터 4세대 이동통신 초고속 패킷 무선전송 기술 연구 개발에 착수하였다. 이 연구 개발은 크게 전송 시스템과 네트워크 분야로 나뉘어지며, 전송 시스템은 다시 low-tier 서비스를 위한 HMI 시스템과 high-tier 서비스를 위한 HMM 시스템을 두 축으로 하여 진행되고 있다. 본 고에서는 HMM 시스템의 연구 개발 계획, 전개 방향 및 목표 등을 간략하게 소개하고자 한다.

• Child Health Nursing Research
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• v.19 no.2
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• pp.85-93
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• 2013

Purpose: The study purposes were to describe the process of developing the Korean versions of the Six Dimension Scale of Nursing Performance (Six-D) and Student Nurse Stress Index (SNSI) and psychometric evaluation of the two measurements. Methods: This was a methodology study using a descriptive cross-sectional design with 51 nursing students in 4th year of university. Internal consistency reliability was assessed using Cronbach alphas. Construct validity was determined by exploring correlations among Six-D, SNSI, objective structured clinical examination (OSCE), self-efficacy and grade point average (GPA). Results: Internal consistency reliability of Six-D and SNSI was acceptable with Cronbach's ${\alpha}$ of .95 and .82. Correlation analysis to determine construct validity revealed that Six-D presented positive correlations with OSCE (r=.109~.272) and self-efficacy (r=.005~.161) and negative correlation with GPA (r=-.246~-.394), although all were not statistically significant. SNSI presented all negative correlations with OSCE (r= -.007~-.238), self-efficacy (r=-.246~-.394), and GPA (r=-.092~-.426) and were mostly statistically significant except OSCE. Conclusion: Six-D needs more evidence to confirm validity to predict observed clinical competency and theoretical relationships with self-efficacy and GPA. However, SNSI presented trends of expected relationships with relevant variables. Therefore, further research is recommended in testing validity of Six-D with other student populations.

• Journal of Oral Medicine and Pain
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• v.23 no.4
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• pp.353-359
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• 1998

The purpose of this study is reveal the relationship between halitosis and personal profile. The personal characteristics of halitosis patient were studied by symptom checklist-90- revision(SCL-90-R). 135 halitosis patients, 118 TMD patients(control torup 1) and 90 normal persons(control group 2) were selected for this study at the halitosis clinic or the Department of Oral Diagnosis and Oral Medicine, Kyung Hee Dental Hospital. T-scores were analyzed with Korean manual of SCL-90-R. A t-test was used to evaluate the overall group effect and the values were significant at the 0.05 level. The obstained results were as follows : 1. Mean value of T-scores on 9 basic scales of SCL-90-R in all groups(Halitosis patients, TMD patients and normal) was within normal range. 2. When compared with normal group, TamD patients gorup were significantly higher in sclaes of Somatization (p<0.01), Obsession-Compulsion(p<0.05), Depresison(p<0.05), Anxiety(p<0.01), Hostility(p<0.05). 3. When compared with normal group, halitosis patients group were significantly higher in scales of Somatization(p<0.05), Obsessoin-Compulsion(p<0.05), Interpersonal Sensitivity (p<0.05), Psyhcoticism(p<0.05). This data suggests that psychopathologic trends may be associated with halitosis and can be estimated by SCL-90-R questionnaire.

• Journal of Hydrogen and New Energy
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• v.31 no.4
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• pp.351-362
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• 2020

Recently, renewable power is rapidly increasing globally due to extensive effort to mitigate climate change and conventional power generation industry faces new challenges. The gas turbine technology has potentials to expand its role in future power generation based on the intrinsic characteristics such as fuel diversity and fast load following ability. Hydrogen is one of the most promising fuel in terms of reducing emissions and storing variable renewable energy and replacing hydrocarbon fuel with hydrogen has become very popular. Therefore, this paper presents the core technologies to combust hydrogen added fuel efficiently in gas turbines and the analysis of domestic and international R&D trends.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.12 no.1
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• pp.27-34
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• 2006

Nanotechnology is playing an increasingly important role in the development on most areas of science and technology. Because of its potential of providing novel performance at the nanoscale, the nanotechnology can influence a wide range of applications such as information, energy, environment and biology, all essential for socioeconomic development in the near future. In the packaging industry, the main applications of nanotechnology are (1) to enhance durability, (2) improve gas and oxygen barriers of raw materials for films and packaging, (3) create new functional sensors, and (4) lengthen shelf life for the packaged food quality and will also help in pharmaceuticals and cosmetics. Nanotechnology is growing in an international interactions which accelerate in science, education, and industrial R&D. Government, industries and the business sector in Korea have shown a strong ambition towards the development of nanotechnology for the future. Meanwhile, a strategic investment in packaging area is much smaller compared to supporting research and development (R&D) of various major research areas. This article were reviewed the status and trends of current packaging research and development activities using nanotechnology in Korea, USA, Japan, and other international nations.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.4
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• pp.512-518
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• 2011

The marine equipment industry in Korea has been growing along with shipbuilding industry since early 1980s. Major shipbuilding might be predicted to shift to China in the near future. Moreover, new paradigm of e-navigation is about to get geared in the real world, which was specifically noted by IMO (International Maritime Organization). In order to catch up with rapid changes in the environments, the industry sector should move fast, the public sector should setup proper measures, and the academic sector should spur the research and development of new technologies. In this paper, international marin equipment markets and standardization trends are presented along with several representative R&D activities.