• 한국학교보건학회지
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• 제10권2호
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• pp.193-211
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• 1997

The study was designed to gain necessary basic data in order to grasp the health knowledge, attitude, and practice level of students and teachers of elementary, middle and high schools. This study was conducted through interviews of 3,400 students and 1,022 teachers attending 14 different schools large, middle and small cities and rural towns during a period of nine months (from Oct. 2 1995 to Jun. 30 1996). By the results of this study, the recommendations can be summarized as follows: 1. A school health development committee should be established of 10 members: school health related teachers (physical trainers, nurses, and teachers in charge of health), parents, persons related to health administration, local medical doctors, and student reprensentatives in order to support and immplement school health development plans. 2. Like advanced countries, a health class of 2~4 hours should beplaced in middle and high schools. A nurse majoring in health from a university should be the teacher. 3. A curriculum of health should contain the following: education on health, sex, alcohol, tabacco, the misuse of the drugs, the structure and function of human body, the growth of the body, mental health, safety and emergency care, the prevention of disease, proper eating habits and nutrition, daily health life, family health education, society health, community health, environmental pollution and individual responsibility. 4. Create a school health promotion center, with a nurse's office, and a sports center which has health machines (bars, aerobics, training, twist machine, belt massage, running machine, bench press, chest waist, hack hip extension machine) as well as a physical strength measuring machine (muscular strength, alertness, flexibility, endurance, lung functions and so on), so that the teaching staff and students can use them and train their bodies. 5. Through a refresher education program, urge teachers to understand school health promotion services. 6. Regulate a standard and establish a system of monitoring the physical enviroment of the school (the height of desks and chairs, illumination facilities, ventilation facilities, safe drinking water). 7. Create a check list of health to evaluate improvement.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.523-523
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• 2012

As the wafer geometric requirements continuously complicated and minutes in tens of nanometers, the expectation of real-time add-on sensors for in-situ plasma process monitoring is rapidly increasing. Various industry applications, utilizing plasma impedance monitor (PIM) and optical emission spectroscopy (OES), on etch end point detection, etch chemistry investigation, health monitoring, fault detection and classification, and advanced process control are good examples. However, process monitoring in semiconductor manufacturing industry requires non-invasiveness. The hypothesis behind the optical monitoring of plasma induced ion current is for the monitoring of plasma induced charging damage in non-invasive optical way. In plasma dielectric via etching, the bombardment of reactive ions on exposed conductor patterns may induce electrical current. Induced electrical charge can further flow down to device level, and accumulated charges in the consecutive plasma processes during back-end metallization can create plasma induced charging damage to shift the threshold voltage of device. As a preliminary research for the hypothesis, we performed two phases experiment to measure the plasma induced current in etch environmental condition. We fabricated electrical test circuits to convert induced current to flickering frequency of LED output, and the flickering frequency was measured by high speed optical plasma monitoring system (OPMS) in 10 kHz. Current-frequency calibration was done in offline by applying stepwise current increase while LED flickering was measured. Once the performance of the test circuits was evaluated, a metal pad for collecting ion bombardment during plasma etch condition was placed inside etch chamber, and the LED output frequency was measured in real-time. It was successful to acquire high speed optical emission data acquisition in 10 kHz. Offline measurement with the test circuitry was satisfactory, and we are continuously investigating the potential of real-time in-situ plasma induce current measurement via OPMS.

• 한국주거학회논문집
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• 제27권4호
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• pp.1-11
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• 2016

This study aims to find out the cause of delay by analyzing the process of 12 Core-based Improvement pilot projects, especially focused on lands, buildings, population status. For this purpose, it performed a literature research on maintenance plan reports, various statistics of building and population status analysis, a field research and an individual interview with public officials in charge at local governments of 12 project districts. The findings are as follows; 1) it was difficult to cope flexibly to environmental changes because the core sector was so large that the plan was led to areal improvement. 2) the project was selected without reflecting the characteristics of the core sector and the area of residents-led renovation properly in terms of building status such as building density and old buildings ratio, 3) the coordinator group for socially disadvantaged class in the district was not operated and thus foundation for residents-led renovation was not set up. In conclusion, it should be presented the proper size of the core sector when the core-based residential environment improvement project is initiated in the future. In addition, building status is taken into consideration when designating the core sector and the area of residents-led renovation. The coordinator group needs to be operated from the early stage of the project as well.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.631-631
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• 2013

Battery has major drawbacks including its size and life expectancy, and environmental problem. As an alternative, energy harvesting is emerging as a potential solution to replace battery along with more energy-efficient IT devices. The idea of harnessing energy from our living environment is sustainable, semi-permanent, and eco-friendly. Also, unlike battery, energy harvester does not require much space to store energy. Therefore, energy harvesting can provide a better source of power for small, portable, and wireless devices. Among various ways of harvesting energy from our surroundings, triboelectricity is chosen due to its potential to be miniaturized, and efficient. Triboelectric effect occurs as two different materials with different polarity of charge separation come into contact through friction, and then become separated so that electric potential difference is achieved. In this research, such characteristic of triboelectricity is used as a way to convert ambient mechanical energy into electric energy.Series of recent researches have shown promising results that the triboelectric energy harvester can be simple and cost effective. However, sufficient electricity level required to operate mobile devices has not yet been achieved.In this research, our group focuses on the design and optimization of triboelectric energy harvesting device to enhance its output. By using maskless lithography to pattern Kapton film and silicon substrate, which is used as a mold for PDMS thin layer, and sputtering metal electrodes on each side, we fabricate and demonstrate different designs of triboelectric energy harvester that utilizes the contact electrification between a polymer thin film and a metal thin foil. In order to achieve optimized result, the output voltage and current are measured under diverse conditions, which include different surface structure and pattern, material, and the gap between layers.

• Bulletin of the Korean Chemical Society
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• 제32권3호
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• pp.988-992
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• 2011

$CO_2$ adsorption on mineral sorbents has a potential to sequester $CO_2$. This study used a density functional theory (DFT) study of $CO_2$ adsorption on barium oxide (BaO) in the presence of $H_2O$ to determine the role of $H_2O$ on the $CO_2$ adsorption properties on the ($2{\times}2$; $11.05\;{\AA}{\times}11.05\;{\AA}$) BaO (100) surface because BaO shows a high reactivity for $CO_2$ adsorption and the gas mixture of power plants generally contains $CO_2$ and $H_2O$. We investigated the adsorption properties (e.g., adsorption energies and geometries) of a single $CO_2$ molecule, a single $H_2O$ molecule on the surface to achieve molecular structures and molecular reaction mechanisms. In order to evaluate the coordinative effect of $H_2O$ molecules, this study also carried out the adsorption of a pair of $H_2O$ molecules, which was strongly bounded to neighboring (-1.91 eV) oxygen sites and distant sites (-1.86 eV), and two molecules ($CO_2$ and $H_2O$), which were also firmly bounded to neighboring sites (-2.32 eV) and distant sites (-2.23 eV). The quantum mechanical calculations show that $H_2O$ molecule does not influence on the chemisorption of $CO_2$ on the BaO surface, producing a stable carbonate due to the strong interaction between the $CO_2$ molecule and the BaO surface, resulting from the high charge transfer (-0.76 e).

• Journal of Electrochemical Science and Technology
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• 제2권4호
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• pp.187-192
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• 2011

Photoelectrochemical performances of ZnO electrodes are enhanced by coupling with cobalt-based catalyst (CoPi) in phosphate electrolyte (pH 7). For this study, hexagonal pillar-shaped ZnO nanorods are grown on ZnO electrodes through a chemical bath deposition, onto which CoPi is deposited with different photodeposition times (10-30 min). A scanning electron microscopic study indicates that CoPi deposition does not induce any change of ZnO morphology and an energy-dispersive X-ray spectroscopic analysis shows that inorganic phosphate ions (Pi) exist on ZnO surface. Bare ZnO electrodes generate the current of ca. $0.36mA/cm^2$ at a bias potential of 0.5 V vs. SCE, whereas ZnO/CoPi (deposited for 10 min) has ca. 50%-enhanced current ($0.54mW/cm^2$) under irradiation of AM 1.5G-light ($400mW/cm^2$). The excess loading of CoPi on ZnO results in decrease of photocurrents as compared to bare ZnO likely due to limited electrolyte access to ZnO and/or CoPi-mediated recombination of photogenerated charge carriers. The primary role of CoPi is speculated to trap the photogenerated holes and thereby oxidize water into molecular oxygen via an intervalency cycle among Co(II), Co(III), and Co(IV).

• 수면정신생리
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• 제4권1호
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• pp.77-88
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• 1997

The purpose of this study was to investigate the prevalence, primary causes, and management of insomnia newly admitted patients in a university hospital. Subjects consisted of 168 adult patients (95 men and 73 women, 88 medical and 94 surgical patients) newly admitted to Gyeongsang National University Hospital from September 7 through September 27, 1996. Sleep patterns of all subjects in the usual nights before admission(UN), the previous night to admission(PN), the night on admission(ON), and the 5th night after admission(5N) were investigated using the Korean version of the St. Mary's Hospital Sleep Questionaire. In addition, all insomnia patients and their doctors and nurses in charge were interviewed by psychiatric residents. Additionally, their medical records were reviewed. Prevalence of insomnia were 22.6% in the UN, 42.9% in PN, 51.8% in ON, and 43.5% in 5N. The prevalence of insomnia was significantly increased immediately before and after admission. There were no significant differences in the prevalence of insomnia by age and sex. The most ammon primary causes of insomnia were somatic symptoms and psychological factors in PN, somatic symptoms and noise in ON and 5n. Only 17 (10.1%) of insomnia patients took medicstions for insomnia control(analgesics in 15, hypnotics in 2). These results shorred that the prevalence of insomnia was significantly increased on hospitalization due to somatic symptoms, environmental factors, and psychological factors, but nearly none were adequately managed.

• 설비공학논문집
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• 제17권10호
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• pp.883-890
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• 2005

In this study, 2 pure hydrocarbon refrigerants of R1270 (Propylene) and R290 (Propane) and 3 binary mixtures composed of R1270, R29O and R152a were tested in a refrigerating bench tester with a scroll compressor in an attempt to substitute R502 used in most of the low temperature applications. The test bench provided 3\sim3.5$ kW capacity and water and water/glycol mixture were employed as the secondary heat transfer fluids. All tests were conducted under the same external conditions resulting in the average saturation temperatures of -28 and $45^{\circ}C$ in the evaporator and condenser, respectively. Test results showed that all refrigerants tested had $9.6\sim18.7\%$ higher capacity and $17.1\sim27.3\%$ higher COP than R502. The compressor discharge temperature of R1270 was similar to that of R502 while those of all other refrigerants were $23.7\sim27.9\%$ lower than that of R502. For all alternative refrigerants, the amount of charge was reduced up to $60\%$ as compared to R502. Overall, these alternative refrigerants offer better system performance and reliability than R502 and can be used as long term substitutes for R502 due to their excellent environmental properties.

• 한국컴퓨터정보학회논문지
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• 제10권3호
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• pp.201-208
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• 2005

이벤트 알림 서비스는 이벤트 기반의 메시징 서비스 미들웨어로 비즈니스 응용 프로그램, 분산 시스템 관리, 그리고 웹 서비스 통합을 위한 응용 프로그램 영역에서 사용하고 있다. 본 논문에서는 주제 기반의 이벤트 분배 서비스와 다양한 메시지 통신 서비스를 제공하는 이벤트 알림 서비스 아키텍처를 제시한다. 이벤트 분배 서비스는 이벤트들을 비동기적인 방식으로 전송하며 이벤트에 정의된 주제 정보와 시스템의 환경 정보를 활용하여 이벤트 전송이 빠르게 하였다. 또한 이벤트의 내용에 대한 필터링 기능을 포함하고 있다. 메시지 통신 서비스는 다양한 형식의 메시지와 다양한 통신 프로토콜을 지원하기 위한 통신 인프라스트럭처이다. 응용 프로그램의 도메인과 환경에 따라, 통신 인프라스트럭처는 성능과 유용성을 최적화하기 위해 재배치하여 사용할 수 있다. 본 논문에서는 우리가 개발한 이벤트 알림 서비스에 대한 성능 분석한 결과를 다양한 형식의 메시지 형식과 통신 프로토콜을 대상으로 제시한다.

• 한국자동차공학회논문집
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• 제12권1호
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• pp.17-24
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• 2004

As the environmental pollution becomes serious global problem, the regulation of emission exhausted from automobiles is strengthened. Therefore, it is very important to know how to reduce the NOx and PM simultaneously in diesel engines, which has lot of merits such as high thermal efficiency, low fuel consumption and durability. By this reason, the new concept called as Homogeneous Charge Compression Ignition(HCCI) engines are spotlighted because this concept reduced NOx and P.M. simultaneously. However, it is well known that HCCI engines increased HC and CO. Thus, the investigation of combustion characteristics which consists cool and hot flames for HCCI engines were needed to obtain the optimal combustion condition. In this study, combustion characteristics for direct injection type HCCI engine such as quantity of cool flame and hot flame, ignition timing and ignition delay were investigated to clarify the effects of these parameters on performance. The results revealed that diesel combustion showed the two-stage ignition of cool flame and hot flame, the rate of cool flame increase and hot flame decrease with increasing intake air temperature. On the other hand, the gasoline combustion is the single-stage ignition and ignition timing is near the TDC. In addition mixed fuel combustion showed different phenomenon, which depends on the ratio of gasoline component. Ignition timing of mixed fuel is retarded near the TDC and the ignition delay is increased according to ratio of gasoline.