Quantitative Analysis on Air-Dispensing Parameters for Manufacturing Dome Lenses of Chip-on-Board LED System

Jeon, Eun-Chae,Lee, Je-Ryung,Je, Tae-Jin,Choi, Doo-Sun,Ham, Young-Bog,Lee, Eung-Sug,Choi, Sang-Kyu,Kim, Hwi Korean Society for Precision Engineering 2014 International Journal of Precision Engineering and Vol.15 No.11

A COB(chip-on-board) LED(light emitting diode) system has advantages such as low cost and good heat dissipation. LED chips are bonded on PCB(printed circuit board) directly without packaging process in case of COB LED systems. Dome lenses made of polymeric resin are generally covered on the bonded LED chips by air dispensing for preventing mechanical damage and making white light. However, it is hard to control the shape of dome lenses precisely due to viscosity of the polymeric resin. We analyzed the relationship of the shape of dome lenses and experimental conditions of the air dispensing in this study. We introduced a new parameter, air pressure * dispensing time, whose physical meaning is impulse per unit area, and obtained much clear relationship of dispensing parameters and shape parameters of the dome lens. This relationship was similar to viscoelastic behavior. The aspect ratio (height over diameter) was increased as the new parameter increased, and was converged to a certain value. The maximum aspect ratio could be calculated by Young's equation of contact angle.

망원경에 대한 초등 예비 교사들의 개념 조사

채동현,양종천,김은영 전주교육대학교 과학교육연구소 2001 科學 敎育 硏究 論文集 Vol.23 No.1

Presevice students' conceptions on the telescope were Investigated. Samples consisted of 63 students in Chonju National University of Education. The open-ended written questionnaire were used. The result were that students' naive theories on the telescope were numerous. For example, 87% students held the idea that when someone salts a object through the telescope, the object could be seen larger. This study was also discussed the teaching strategies to overcome these naive theories on the telescope.

우리나라 정신요양시설의 이용현황 및 평가에 관한 연구

채은희,서동우,이효영 대한보건협회 2003 대한보건연구 Vol.29 No.1

After the Mental Health Act was established at 1995, mental health service in korea has continuously been changed. The demand for long-term mental health care is on rise as the number of patient among population and social costs increases. In addition, as social concern about patient s quality of life enlarged, people give weight to quality management and evaluation of long term mental health care facilities. Through the evaluation of long-term mental health care facilities, the quality of mental health care can be improved and the function of long-tern mental health care facilities will be identified in mental health care system. Therefore this article will be used as a basic data for not only enhancing their service quality, but setting role and function of long-term mental health care facilities in health care delivery system. From the evaluation of long-term mental health care facilities, the eighty percents of a total 55 facilities was high or middle level. Physical environment items were at the highest level in evaluation parts but system management items were at the lowest level. So system management should be improved. The evaluation of long-term care facilities is a chance for checking the system and finding out problems in running the facilities. Also this evaluation will help to identify the role and function of long-term mental care facilities in the health care system.

洛東江河口粘土의 壓密係數에 관한 硏究

嚴采永 동아대학교 환경문제연구소 1984 硏究報告 Vol.7 No.2

This study was aimed to establish the relationship of the coefficient of consolidation(Cv) derived from Terzaghi's theory with the measured coefficient of permeability(k) and the relationship between void ratio(e) and permeability(k) of the soil. Finally the equation for coefficient of consolidation based on the laboratary test has been derived for easy application as shown below. The general characteristics of the consolidation coefficient which were found during this study are summarized as belows; 1) The value of coefficient of consolidation calculated from the measured coefficient of permeadility has shown the lower value than fitting method but the higher value accordingly with the increase in applied load. 2) The infinite strain theory of Terzaghi is found out being more consistance with this study than the finite strain theory. 3) Following coefficients have been obtained for the equation of Cv=αβ^(n) which was assumed in this study; α=2.337×10^(-4) σ￣, β=-0.204logσ￣+1.354 4) Coefficient of Permeability has been expressed as k=1.858×10^(-6) e^(2.1418) 5) The final equation for coefficient of consolidation is proposed as function of void as log Cv=-5.5347 log (1.858×10^(-6) e^(2.1418))-31.4

과학 교육과정상의 창조론과 진화론에 대한 초등 예비 교사의 인식 조사

채동현,최명재,김은영 전주교육대학교 과학교육연구소 2001 科學 敎育 硏究 論文集 Vol.23 No.1

The creation-evolution issued a contentious battle in school education.This study was surveyed on preservice students' idea on creation and evolution in science curriculum.Samples consisted of 150 preservice students in Chonju National University of Education.One instrument was used: a Likert scale type.The instrument had 50 items. As a result, many students suggested that Korean science curriculum developer keep in mind on reflecting creation as well as evolution In the future science curriculum.

인천지역 한 대학병원에서 진단된 기관지천식 중 직업관련성 천식

채창호,진영우,김은아,최승원,강성규,최용휴 大韓産業醫學會 1999 대한직업환경의학회지 Vol.11 No.2

Bronchial Asthma could be developed by occupational origin. 4-16% of bronchial asthmas are known to be related to occupational exposure. However, occupational asthma has not been reported from the periodic occupational health examination, but reported through case report from clinicians. The authors analysed hospital records to find out work-related bronchial asthma and their occupational characteristics at a university hospital in Inchon. All records which were confirmed as bronchial asthma in adult by an allegist from June, 1996 to May, 1998 were selected. Through record reviewing, any suspected work related asthma was selected and the inteview was done by phone or at the out-patient clinic. The possible cases were confirmed by additional tests including specific bronchial provocation test. Sixteen(3.9%) out of 411 bronchial asthma were confirmed as work-related asthma. Eight cases out of 16 worked at furniture industry, three worked at dye manufacturing and two worked at musical instrument manufacturing industry. Others worked at farm and machinary industry. The confirmed asthmogen were toluene diisocyante(8), reactive dye(3), and grain dust(1). None of the cases was detected as work-related asthma in the periodic health examination. Twelve out of sixteen occupational asthma patients discontinued their work. The results suggested that many patients with occupational asthma were not reported and the periodic health examination was not an effective system for detecting the workrelated asthma. Thus setting up the surveillance system involving allergist or pulmonologist would be important to detect and prevent occupational asthma.

초산 중독에 의한 범발성 혈관내 응고증: 1증례 보고

곽은경,김동자,박지영,배한익,채종민,곽정식,박태인 大韓法醫學會 1998 대한법의학회지 Vol.22 No.2

Strong corrosive acid is accidentally ingested by children or by psychiatric patients for the purpose of suicidal attempt. Late complications include chemical burn to pharyunx, perforation and stricture of upper gastrointestinal tract, respiratory insufficiencyand renal failure caused by hemoglobinuria following hemolysis. Acetic acid is difficult to ingestion large volume in a time because it is a strong irritant, provocating painful pharynx, and its autopsy case is rare. We report an autopsy case of acetic acid intoxication with acute disseminated intravascular coagulation (DIC) in several hours. We present pathogenesis of acetic acid intoxication and the associated forensic problems. A comatous 39-year-old female was admitted to emergency room 6 hours after she swallowed 90 gm of acetic acid. She was treated with gastric lavage but she was expired 9 hours after swallowing acetic acid. She was consulted to Department of Forensic Medicine of Kyungpook National University School of Medicine. She was grossly icteric and livor mortis was generally dark red. External wounds were 10 hemorrhagic lesions with 5 x 3.7cm and 3 x 2.8cm on the left arm and hand dorsum and facial abrasions. Internal gross examination revealed several purpural lesions in the gastric serosal surface and greater omentum. Microscopically, the stomach showed diffuse mucosal coagulation necrosis and intravascular hyalinized or fibrinoid thrombi in submucosal blood vessels. Liver showed necrosis of periportal area (zone I) and intracellular cholestasis around the central vein. Sections from renal tissue frequently show hemoglobin casts in the tubules and RBCs in the Bowman's capsules. Acetic acid of a remnant bottle, sampled blood and bloody necrotic tissues in the stomach were toxicologically examined in National Science Laboratory. The purity of ingested acetic acid is 98%, the concentration of acetic acid ion in blood is 734ppm and the content in gastric juice is 0.09%. In patients after acetic acid ingestion, DIC is most probably caused by procoagulants, produced by extensive acid-induced necrosis of the upper gastrointestinal tract. In this case, several purpural lesions were revealed on the arm, around facial abrasion and intravenous injection sites of the wrists. These are important to differentiate with contusion because she was battered before acetic acid ingestion. Purpurae in DIC are poorly demarcated, dark purple elevations with spreading margin but subcutaneous hemorrhage in contusion is grayish black or dark red with well demarcation (Table 2). But careful examination should be considered because traumatic hemorrhage is also exaggerated and mixed in DIC. (The Korean Journal of Legal Medicine)

성인 IgA 신병증의 임상적 고찰

김영학,권용은,허경무,윤채중,김종인,김건영,배학연,정종훈 조선의대 1998 The Medical Journal of Chosun University Vol.23 No.1

효율적인 군 전직지원체제 정립 방안

정철영,고재관,황원채,윤희철,박가열,김재호,이성식,김동승,표성일,이건남,양안나,최수정,김은석 한국직업능력개발원 2008 직업능력개발연구 Vol.11 No.1

이 연구의 목적은 제대군인에 대한 효율적인 전직지원을 위해서 현행 전직지원 프로세스에 대한 개선 안과 이에 따른 국방부, 국가보훈처 등 제대군인 전직지원관련 기관 간의 역할분담 및 연계방안에 대해서 제안하는 것이다. 연구는 크게 세 가지 과정을 거쳤다. 첫째, 국내 군 전직지원 실태를 분석하여 문제점과 시사점을 도출하였다. 둘째, 이러한 문제점과 시사점, 군 전직지원 선행연구를 종합하여 효율적인 군 전직지원 프로세스 안을 제시하였다. 셋째, 구축한 군 전직지원 프로세스 안에 따라 주요 군 전직지원 관련 기관인 국방부, 국가보훈처의 역할 분담 안을 제안하였다. This study aims to suggest an improvement plan for the support process of effective occupation change for discharged soldiers and then role assignments among related institutions for supporting discharged soldiers such as Ministry of Defense, Ministry of Patriots and Veterans Affairs, Ministry of Labor and the cooperation plan among the institutions. The study was made in three steps. First, after analyzing currents support facts and status for discharged soldiers, it induced its problems and implications. Second, integrating the findings of previous studies related to support plan on occupation changes for the discharged soldiers, Problems and implications mentioned above, it constructed effective occupation change process for discharged soldiers. Then, according to the established process, it suggested role assignments such as Ministry of Defense, Ministry of Patriots and Veterans Affairs, Ministry of Labor.

버스안내시스템 구축을 위한 도착시간예측 알고리즘 개발

임채문,김은길,공창환,이영우 대구대학교 과학기술연구소 2001 科學技術硏究 Vol.8 No.2

This study proposed the algorithm on the estimation time of bus arrival time, using queue lengths, rules for running traffic signal and GPS position datum. The estimated values by means of proposal algorithms were done by the statistical application test. In this study, queue lengths and vehicle discharge properties based on the video photograph had been surveyed in three traffic signal intersection. The surveyed datum were analyzed that discharge headway times from one to three were about 2.5 seconds. the others were about 1.8 seconds. The datum for investigation and the calculation values by means of proposal algorithms revealed that the results based on the t-test are statistically significant.