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전자공학 및 전자기술의 역사, 현황 그리고 미래 (The history, present status and future perspective of electronics and electronic technologies)

  • 조규심
    • 기술사
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    • 제24권6호
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    • pp.106-112
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    • 1991
  • Electronics has different meanings to different people and in different countries. Hence, let me difine the term in the sense that it is used here. Electronics in the science and the technology of the passage of charged particles in a gas, in a vacumn, or in a semiconductor. The beginning of electronics came in 1895 when H. A. Lorentz postulated the existence of discrete charges called electrons. Two years later J.J. Thompson found these electrons experimentally. In the same year (1897) Braun built what was probaly the first electron tube, essentially a primitive cathode-ray tube. It was not until the start of the 20th century that electronics began to take technological shape. In 1904 Fleming invented the diode which he called a valve. This era begins with the invention of the transistor about 30 years ago. The history of this invention is interesting. M.J. Kelly, director of research(and later president of Bell Laboratories), had the foresight to realize that the telephone system needed electronic switching and better amplifiers. Vacuum tubes were not very reliable, principally because they generated a great deal of heat even when they were not being used, and, particularly, because filaments burned out and the tubes had to be replaced. In 1945 a solid-state physics group wa formed. The foregoing completes the history of electronics and electronic industries up to 1978. There is already a start toward a merging of the computer and the communication industries which might be called information manipulation. This includes storage of information, sorting, computation, information retrieval, and transmission of data. This combination of the computer and the communication fields will penetrate many disciplines. Applications will be made in the fields of law, medicine, biological sciences, engineering, library services publishing banking, reservation systems, management control, education, and defense.

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Lack of Any Relationship of Stomach Cancer Incidence and Mortality with Development in Asia

  • Rafiei, Elahe;Mohammadian-Hafshejani, Abdollah;Towhidi, Farhad;Makhsosi, Behnam Reza;Salehiniya, Hamid
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권8호
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    • pp.3777-3783
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    • 2016
  • Background: The aim of this study was to evaluate the incidence and mortality of stomach cancer, and its relationship with the Human Development Index (HDI) and its components in Asia in 2012. Materials and Methods: This ecological study wa conducted based on GLOBOCAN project of WHO for Asian countries. We assessed the correlations between standardized incidence rates (SIR) and standardized mortality rates (SMR) of stomach Cancer with HDI and its components using SPSS18. Results: A total of 696,231 cases (68.7% in males and 31.3% in females, ratio of 2.19:1) and 524,465 deaths (67.1% in men and 33.0% in women, ratio 2.03:1) were included in 2012. Five countries with the highest SIR of stomach cancer were Republic Korea, Mongolia, Japan, China and Tajikistan. Five countries with the highest SMR of stomach cancer were Mongolia, Tajikistan, Kyrgyzstan, Kazakhstan and China. Correlation between HDI and SIR was 0.241 (p = 0.106), in men 0.236 (p = 0.114) and in women -0.250 (p = 0.094). Also between HDI and SMR -0.250 (p = 0.871) in men -0.018 (p = 0.903) and in women -0.014 (p = 0.927). Conclusions: No significant correlation was observed between the SIR of stomach cancer, and the HDI and its dimensions, such as life expectancy at birth, mean years of schooling, and income level of the population.

GIS를 이용한 물리탐사자료 관리시스템 개발 (A Geophysical Data Management System using GIS)

  • 김지영;최은영;김태현;최선영;고와라;윤왕중
    • 지구물리와물리탐사
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    • 제6권1호
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    • pp.1-6
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    • 2003
  • 대형 건설 공사, 토목 공사 및 지반 분석을 위한 지반조사에서 물리탐사를 적용하여 지반 정보에 대한 방대한 양의 데이터를 획득하고 있으나, 체계적으로 관리되지 못하여 한시적으로만 사용되고 있다. 이와 같은 문제에 대한 대안으로 본 연구에서는 GIS를 이용한 물리탐사자료 관리시스템을 개발함으로써 자료의 효율적 관리와 사용자의 자료 접근 용이성을 도모하고자 하였다. 물리탐사자료 관리시스템을 실무에 이용하면 자료의 체계적 관리와 표준화가 가능할 뿐만 아니라 자료의 중복 구축을 피하고 인터넷 등을 통한 자료의 공유가 가능해짐에 따라 지표 및 지하공간을 효과적으로 개발하고 보전할 수 있는 기초 자료 제공이 가능할 것으로 기대된다.

水酸化鐵 懸濁液에서 空氣酸化에 의한 중금속이온의 Ferrite 생성에 관한 연구 (A Study of Ferrite Formation by Aerial Oxidation of Fe$(OH)_2$ Suspension of Aqueous Solution Containing Heave Metal Ions)

  • Lee, Sung Ho;Hyun, Yong Bum;Kim, Soo Saeng
    • 한국환경보건학회지
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    • 제12권1호
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    • pp.1-14
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    • 1986
  • This investigation was carried out on the study of Ferrite formation by aerial oxidation of Fe $(OH)_2$ suspension of aqueous solution containing heavy metal ions. In this study the optimum reactionary condition of the Ferrite formation in Batch reactor wa studied by aerial oxidation which are subjected to various reaction time and temperature, under the different kinds of R(2NaOH/$FeSO_4$) Values, pH, Air flow rate, and $Fe^2+/M^2+$ mole ratio. The optimum condition for the Ferrite formation in Batch reactor was such that residence Time was 90 min., Temperature $65{\circ}$C, pH 11.0, Air flow rate 2.0l/min and $Fe^{2+}/M^{2+}$ mole ratio 4.0, which was observed by X-Ray diffraction analysis. The relation R-value, pH and ORP affecting the formation of Ferrite is that the jump step in pH 11.0, when a amount of NaOH is added, is steady state to the formation of Ferrite. Effect of R-value of $FeSO_4$ and $FeCl_2$ on the formation of Ferrite in different from each other the optimum condition of the in different from each other the optimum condition of the $FeCl_2$ is R-value 0.7, pH 11.0 and the $FeSO_4$ R-value 1.2, pH 11.0.

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Landsat TM 자료를 이용한 광주시 환경변화 분석 (Environmental Change Analysis of Kwangju City using Landsat TM Data)

  • 박병욱
    • 대한공간정보학회지
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    • 제4권1호
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    • pp.31-41
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    • 1996
  • 도시의 발달에 따른 환경변화를 분석하는 것은 앞으로의 개발계획 수립시 중요한 지표가 된다. 본 연구에서는 Landsat TM자료를 이용하여 최근 10년간 광주시의 토지피복변화를 분석하므로서 도시개발의 확산 추세를 정량화하고 그 특징을 추출하며, 지표면 온도 분석을 통한 영향 평가를 실시하고자 하였다. 토지피복변화의 분석결과 약 3%의 도시지역 증가가 이루어졌으며, 이러한 확산의 대부분이 기존 농경지역에서 진행되었고 논에 비닐하우스 단지가 많이 들어서는 영농형태의 변화를 알 수 있었다. 또한 새로이 광주시에 편입된 광산구의 집중개발 현상을 확인할 수 있었다. 지표면 은도 분석결과 온도가 토지피복종류와 밀접한 관계를 갖고 있으며, 도시확산에 따른 온도변화를 추정해본 결과 여름에 약 $0.3^{\circ}C$의 상승효과를 가져 왔음을 알 수 있었다. 이러한 분석을 통하여 인공위성 자료를 이용한 환경변화 분석의 효율성을 입증하였다.

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건설현장 작업복의 패턴디자인 개선에 따른 동작기능성 평가 (The Evaluation of Movement Functionality on Improved Pattern-Design Working Uniform of Construction Site Worker)

  • 김성숙;김희은
    • 한국의류산업학회지
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    • 제9권2호
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    • pp.237-242
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    • 2007
  • The purpose of this study is to examine the functionality with improved pattern-design working uniform(protocol, P) and current working uniform(control, C). Movement functionality evaluation of improved pattern-design working uniform was carried out through sensory evaluation of working uniform. Movements for the sensory evaluation consisted of four types of up and down and horizontal movements of the shoulders, four types of waist movements and five types of knee movements. The results have been shown as follows: The sensory value of back girth, wrist, side seam area of the "P" with the posture of raising an arm forward up to $90^{\circ}$ and the maximal arm's vertical movement significantly improved compared to the "C". Therefore, it can be concluded that movement functionality was increased with the improved pattern-design working uniform in the respect of arm's up and down movement. Furthermore, for P, Movement functionality improvements were shown in P with arm's horizontal movement, waist bending movement, and knee movement. Current working uniform(C) is jumper-type which wa designed without consideration for movement functionality of the arms and legs. But Pattern-design uniform(P) which was developed in this study. Therefore, the more patterns development, the better movement functionality in working uniform. The improved movement functionality improvements in working uniform will provide not only personal pleasantness but also efficiency of productivity at construction sites. In respect of human body's movement, further study for improved working uniform is required.

Zika Virus on YouTube: An Analysis of English-language Video Content by Source

  • Basch, Corey H.;Fung, Isaac Chun-Hai;Hammond, Rodney N.;Blankenship, Elizabeth B.;Tse, Zion Tsz Ho;Fu, King-Wa;Ip, Patrick;Basch, Charles E.
    • Journal of Preventive Medicine and Public Health
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    • 제50권2호
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    • pp.133-140
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    • 2017
  • Objectives: The purpose of this study was to describe the source, length, number of views, and content of the most widely viewed Zika virus (ZIKV)-related YouTube videos. We hypothesized that ZIKV-related videos uploaded by different sources contained different content. Methods: The 100 most viewed English ZIKV-related videos were manually coded and analyzed statistically. Results: Among the 100 videos, there were 43 consumer-generated videos, 38 Internet-based news videos, 15 TV-based news videos, and 4 professional videos. Internet news sources captured over two-thirds of the total of 8 894 505 views. Compared with consumer-generated videos, Internet-based news videos were more likely to mention the impact of ZIKV on babies (odds ratio [OR], 6.25; 95% confidence interval [CI], 1.64 to 23.76), the number of cases in Latin America (OR, 5.63; 95% CI, 1.47 to 21.52); and ZIKV in Africa (OR, 2.56; 95% CI, 1.04 to 6.31). Compared with consumer-generated videos, TV-based news videos were more likely to express anxiety or fear of catching ZIKV (OR, 6.67; 95% CI, 1.36 to 32.70); to highlight fear of ZIKV among members of the public (OR, 7.45; 95% CI, 1.20 to 46.16); and to discuss avoiding pregnancy (OR, 3.88; 95% CI, 1.13 to 13.25). Conclusions: Public health agencies should establish a larger presence on YouTube to reach more people with evidence-based information about ZIKV.

수치지도 공급을 위한 국립지리원 외부메타데이터의 설계 (Designing External Metadata of National Geography Institute for Distributing Digital Maps)

  • 김계현;김희두;임삼성;이경숙;유승근
    • 한국공간정보시스템학회 논문지
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    • 제1권1호
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    • pp.89-98
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    • 1999
  • 본 연구는 국립지리원 수치지도의 효율적인 관리와 공급을 위하여 외부메타데이터 설계를 목적으로 수행되었다. 보다 효율적이고 세계표준에 부합하는 메타데이터의 표준안을 제작하기 위하여 국외의 표준화 관련 기구의 동향 분석과 함께 선진국의 메타데이터 구축사례를 분석하였으며 이와 함께 국내의 구축사례를 조사하였다. 사용자의 요구를 최대한 수용하기 위하여 국립지리원의 메타데이터 관련 자료를 최대한 수집하여 실무자의 의견을 바탕으로 항목별로 분류를 하였으며, 데이터의 유형별 중요도를 부과하였다. 이러한 기존 자료의 분석을 바탕으로 외부메타데이터의 설계안을 도출하였으며 ISO의 표준안을 최대한 수용하는 표준메타데이터를 제시하였다. 설계된 메타데이터를 바탕으로 실무 적용에 따른 향후 지속적인 연구개발과 보완과 세계적인 표준화의 동향에 따른 메타데이터의 갱신이 필요시 된다.

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구지뽕나무 잎의 항산화 성분 (Anti-oxidant Compounds of Cudrania tricuspidata Leaves)

  • 전인주;이성완;차자현;한정훈;황완균
    • 약학회지
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    • 제49권5호
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    • pp.416-421
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    • 2005
  • Cudrania tricuspidata Bereau (Moraceae) have been used for anti-inflammatory, anti-hepatotoxic, anti-hyper­tensive and anti-diabetic activities. In order to investigate the efficacy of antioxidant activity, the bio-activity guided fraction and isolation of Biologically active substance were performed. $H_{2}O,\;30\%,\;60\%,\;100%$ MeOH and acetone fractions were examined on the antioxidant activity by DPPH method. It was shown that $30\%,\;60\%,\;100\%$ MeOH fractions have sig­nificantly antioxidant activity. From $30\%$ MeOH fraction, two dihydroflavonoid glycosides dihydroquercetin 7-O-$\beta$-D-glu­copyranoside (I), dihydrokaempferol 7-O-$\beta$-D-glucopyranoside (V) were isolated and $60\%$ MeOH fraction, six flavonoids including quercetin 3-O-$\alpha$-L-rhamnopyranosyl($1\rightarrow6$)-$\beta$-D-glucopyranoside (II), quercetin 3-O-$\beta$-D-glucopyranoside (III), quercetin 7-O-$\beta$-D-glucopyranoside (IV), kaempferol 3-O-$\alpha$-L-rhamnopyranosyl($1\rightarrow6$)-$\beta$-D-glucopyranoside (VI), kaempferol 3-O-$\beta$-D-glucopyranoside (VII), kaempferol 7-O-$\beta$-D-glucopyranoside (VIII) were isolated. To investigate the antioxidant activities of each compounds, we measured radical scavening activity with DPPH method and anti-lipid per­oxidative efficacy on low density lipoprotein (LDL) with TBARS assay. Four compounds of quercetin glycosides (I, II, III, IV) showed significant antioxidant activity.

정보 융합 기반 퍼지-베이지안 네트워크 공중 위협평가 방법 (Air Threat Evaluation System using Fuzzy-Bayesian Network based on Information Fusion)

  • 윤종민;최보민;한명묵;김수현
    • 인터넷정보학회논문지
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    • 제13권5호
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    • pp.21-31
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    • 2012
  • 정보 기술의 발전과 더불어 전장상황에서도 정보 시스템들의 고도화가 이루어짐으로써 적기에 대한 정보 획득 및 상황분석은 전장상황에서 주요한 요소가 되었다. 전장상황 분석의 핵심 요소인 위협평가는 피아식별을 통해 식별된 항공 정보를 가지고 해당 상황에 대한 위협치를 평가하여 무기할당에 정보를 제공하는 기술로써, 전장상황의 어느 단계 보다 확실한 정보를 요구하는 단계이다. 전장상황에서 대부분의 위협평가 데이터들은 감지된 센서 값에 의해 연산되어 전달되는데, 기존의 기법들에서 발생할 수 있는 센서 데이터들의 잘못된 연관관계 표현 및 데이터 누락은 전장상황에서의 의사결정에 혼란을 야기 시킬 수 있다. 따라서 각종 센서 데이터들의 연관 관계를 올바르게 정의하고, 센서데이터 누락에 따른 예측 불가능한 전투상황에 대한 신뢰도 높은 위협치 연산 알고리즘을 이용하는 효율적인 의사결정 위협평가 시스템이 필요하다. 본 논문에서는 JDL 정보 융합 모델을 기반으로 애매모호한 관계성을 표현하는데 유리한 퍼지 이론, 데이터 습득의 불확실한 전장상황에서 위협치를 추론하고 상황에 대한 학습이 가능한 베이지안 네트워크를 하이브리드하여 새로운 위협평가 방법을 제안한다. 또, 제안된 방법을 이용하여 가상의 전장 시나리오에 따른 위협평가 결과를 보였다.