• 대기
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• 제21권2호
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• pp.131-142
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• 2011

Spectral solar irradiances were observed using a visible and UV Multi-Filter Rotating Shadowband Radiometer on the rooftop of the Science Building at Yonsei University, Seoul ($37.57^{\circ}N$, $126.98^{\circ}E$, 86 m) during one year period in 2006. 1-min measurements of global(total) and diffuse solar irradiances over the solar zenith angle (SZA) ranges from $20^{\circ}$ to $70^{\circ}$ were used to examine the effects of clouds and total optical depth (TOD) on enhancing four solar irradiance components (broadband 395-955 nm, UV channel 304.5 nm, visible channel 495.2 nm, and infrared channel 869.2 nm) together with the sky camera images for the assessment of cloud conditions at the time of each measurement. The obtained clear-sky irradiance measurements were used for empirical model of clear-sky irradiance with the cosine of the solar zenith angle (SZA) as an independent variable. These developed models produce continuous estimates of global and diffuse solar irradiances for clear sky. Then, the clear-sky irradiances are used to estimate the effects of clouds and TOD on the enhancement of surface solar irradiance as a difference between the measured and the estimated clear-sky values. It was found that the enhancements occur at TODs less than 1.0 (i.e. transmissivity greater than 37%) when solar disk was not obscured or obscured by optically thin clouds. Although the TOD is less than 1.0, the probability of the occurrence for the enhancements shows 50~65% depending on four different solar radiation components with the low UV irradiance. The cumulus types such as stratoculmus and altoculumus were found to produce localized enhancement of broadband global solar irradiance of up to 36.0% at TOD of 0.43 under overcast skies (cloud cover 90%) when direct solar beam was unobstructed through the broken clouds. However, those same type clouds were found to attenuate up to 80% of the incoming global solar irradiance at TOD of about 7.0. The maximum global UV enhancement was only 3.8% which is much lower than those of other three solar components because of the light scattering efficiency of cloud drops. It was shown that the most of the enhancements occurred under cloud cover from 40 to 90%. The broadband global enhancement greater than 20% occurred for SZAs ranging from 28 to $62^{\circ}$. The broadband diffuse irradiance has been increased up to 467.8% (TOD 0.34) by clouds. In the case of channel 869.0 nm, the maximum diffuse enhancement was 609.5%. Thus, it is required to measure irradiance for various cloud conditions in order to obtain climatological values, to trace the differences among cloud types, and to eventually estimate the influence on solar irradiance by cloud characteristics.

• Nuclear Engineering and Technology
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• 제48권5호
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• pp.1273-1279
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• 2016

Production of iodine-131 by neutron activation of tellurium in tellurium dioxide ($TeO_2$) material requires a target that meets the safety requirements. In a radiopharmaceutical production unit, a new lid for a can was designed, which permits tight sealing of the target by using tungsten inert gaswelding. The leakage rate of all prepared targets was assessed using a helium mass spectrometer. The accepted leakage rate is ${\leq}10^{-4}mbr.L/s$, according to the approved safety report related to iodine-131 production in the TRIGA Mark II research reactor (TRIGA: Training, Research, Isotopes, General Atomics). To confirm the resistance of the new design to the irradiation conditions in the TRIGA Mark II research reactor's central thimble, a study of heat effect on the sealed targets for 7 hours in an oven was conducted and the leakage rates were evaluated. The results show that the tightness of the targets is ensured up to $600^{\circ}C$ with the appearance of deformations on lids beyond $450^{\circ}C$. The study of heat transfer through the target was conducted by adopting a one-dimensional approximation, under consideration of the three transfer modes-convection, conduction, and radiation. The quantities of heat generated by gamma and neutron heating were calculated by a validated computational model for the neutronic simulation of the TRIGA Mark II research reactor using the Monte Carlo N-Particle transport code. Using the heat transfer equations according to the three modes of heat transfer, the thermal study of I-131 production by irradiation of the target in the central thimble showed that the temperatures of materials do not exceed the corresponding melting points. To validate this new design, several targets have been irradiated in the central thimble according to a preplanned irradiation program, going from4 hours of irradiation at a power level of 0.5MWup to 35 hours (7 h/d for 5 days a week) at 1.5MW. The results showthat the irradiated targets are tight because no iodine-131 was released in the atmosphere of the reactor building and in the reactor cooling water of the primary circuit.

• 한국음향학회지
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• 제24권8호
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• pp.481-491
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• 2005

이 연구의 목적은 사운드스케이프의 의미론적 관점에 기초하여 도시의 거리경관에 관한 청각적 이미지의 평가구조를 파악하는 것이다. 캡션평가법이라는 새로운 환경심리조사수법을 이용하여 2001년부터 2005년까지 총45명의 대학생이 남원시의 주요 거리를 걸으면서 듣고 느끼는 소리의 이미지 파악을 위한 현장조사에 참가하고, 그 결과 청각적 경관에 대한 요소, 특징, 인상 및 선호도 등을 포함한 다양한 자료를 얻을 수 있었다. 남원시에 있어서, 청각적 이미지의 구성 요소는 자연음, 그리고 기계음, 사회음, 지시음 등을 포함한 인공음으로 분류되고, 청각적 경관의 특징은 소리종류, 양태, 상황, 성질, 주변관계, 이미지 등으로, 그리고 청각적 경관의 인상은 인간의 감성, 거리의 분위기, 소리 자체의 특성이라는 3가지 카테고리로 분류된다. 청각적 경관과 판단과의 관계로 부터, 청각적 경관의 요소, 특징, 인상 등은 긍정적, 중립적, 부정적 이미지 등의 항목으로 구성된다. 또한, 남원시의 거리경관의 평가구조모델로부터 그 장소 또는 공간의 청각적 이미지특성을 파악할 수 있었다.

• 대기
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• 제29권5호
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• pp.671-687
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• 2019

This study evaluates the long-term seasonal predictability of summer (June, July and August) heatwaves over South Korea using 30-year (1989~2018) Hindcast data of the Pusan National University Coupled General Circulation Model (PNU CGCM)-Weather Research and Forecasting (WRF) chain. Heatwave indices such as Number of Heatwave days (HWD), Heatwave Intensity (HWI) and Heatwave Warning (HWW) are used to explore the long-term seasonal predictability of heatwaves. The prediction skills for HWD, HWI, and HWW are evaluated in terms of the Temporal Correlation Coefficient (TCC), Root Mean Square Error (RMSE) and Skill Scores such as Heidke Skill Score (HSS) and Hit Rate (HR). The spatial distributions of daily maximum temperature simulated by WRF are similar overall to those simulated by NCEP-R2 and PNU CGCM. The WRF tends to underestimate the daily maximum temperature than observation because the lateral boundary condition of WRF is PNU CGCM. According to TCC, RMSE and Skill Score, the predictability of daily maximum temperature is higher in the predictions that start from the February and April initial condition. However, the PNU CGCM-WRF chain tends to overestimate HWD, HWI and HWW compared to observations. The TCCs for heatwave indices range from 0.02 to 0.31. The RMSE, HR and HSS values are in the range of 7.73 to 8.73, 0.01 to 0.09 and 0.34 to 0.39, respectively. In general, the prediction skill of the PNU CGCM-WRF chain for heatwave indices is highest in the predictions that start from the February and April initial condition and is lower in the predictions that start from January and March. According to TCC, RMSE and Skill Score, the predictability is more influenced by lead time than by the effects of topography and/or terrain feature because both HSS and HR varies in different leads over the whole region of South Korea.

• 통합자연과학논문집
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• 제4권2호
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• pp.149-157
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• 2011

Urbanization of the world's population has given rise to more than 450 cities around the world with populations in excess of 1 million (megacity) and more than 25 so-called metacities with populations over 10 million (Brinkhoff, 2010). The United States today has a total resident population of more than 308,500,000 people, with 81 percent residing in cities and suburbs as of mid - 2005 (UN, 2008). Urban meteorology is the study of the physics, dynamics, and chemistry of the interactions of Earth's atmosphere and the urban built environment, and the provision of meteorological services to the populations and institutions of metropolitan areas. While the details of such services are dependent on the location and the synoptic climatology of each city, there are common themes, such as enhancing quality of life and responding to emergencies. Experience elsewhere (e.g., Shanghai, Helsinki, Tokyo, Seoul, etc.) shows urban meteorological support is a key part of an integrated or multi-hazard warning system that considers the full range of environmental challenges and provides a unified response from municipal leaders. Urban meteorology has come to require much more than observing and forecasting the weather of our cities and metropolitan areas. Forecast improvement as a function of more and better observations of various kinds and as a function of model resolution, larger ensembles, predicted probability distributions; Responses of emergency managers, government officials, and users to improved and probabilistic forecasts; Benefits of improved forecasts in reduction of loss of life, property damage, and other adverse effects. A national initiative to enhance urban meteorological services is a high-priority need for a wide variety of stakeholders, including the general, commerce and industry, and all levels of government. Some of the activities of such an initiative include: conducting basic research and development; prototyping and other activities to enable very--short and short range predictions; supporting and improving productivity and efficiency in commercial and industrial sectors; and urban planning for long term sustainability. In addition urban test-beds are an effective means for developing, testing, and fostering the necessary basic and applied meteorological and socioeconomic research, and transitioning research findings to operations. An extended, multi-year period of continuous effort, punctuated with intensive observing and forecasting periods, is envisioned.

• 한국지구과학회지
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• 제23권4호
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• pp.349-356
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• 2002

한반도 동해에서 Topex/Poseidon위성 고도레이더로부터 관측된 해수면과 울릉도, 포항, 속초의 조위계에서 관측된 해수면을 비교하여 두 자료의 연계성을 분석하고 위성에서 관측된 해수면자료의 객관성을 검증하였다. 1992년부터 1997년 사이에 관측된 T/P MGDR 관측자료로부터 해수면을 추출하기 위하여 대기보정 및 지구물리학적인 보정을 실시하였다. 조위계로부터 관측된 해수면과의 비교를 위해 조위관측소로부터 반경 약 55km내에 위치하는 관측값들을 평균하였다. 위성 해수면과 조위계 해수면을 비교한 결과 내해역에 위치한 포항 및 속초가 외해역에 위치한 울릉도에비해서 낮은 연관성을 보였다. 200일을 기준으로 저역통과필터를 처리했을 때 외해역에 위치한 울릉도는 상관값이 0.91로 매우 높은 유의성을 보였고, 내해역에 위치한 포항 및 속초는 각각 0.58 및 0.65로서 울릉도에 비해서 상대적으로 낮은 유의성을 보였다. 이러한 큰 차이는 M2, S2, K1 분조 등에 의한 조석변형 때문에 발생하는 현상으로 볼 수 있고, 이는 주로 T/P 자료처리에 사용된 조석모델의 오차로 볼 수 있고, 이를 저역통과필터를 적용하여 효과적으로 제거하였다. 대체로 외해역의 경우는 60, 120, 180, 200일의 필터를 순차적으로 처리함에 따라 상호 두 자료간의 유의성이 점차적으로 개선되는 것을 확인할 수 있었으나 내해역의 경우에는 거의 유의성이 개선되지 않는 것으로 확인되었다.

• 한국식품영양과학회지
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• 제34권7호
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• pp.1028-1034
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• 2005

본 연구에서는 강원도 소재 대학교에 재학 중인 학부 학생을 대상으로 교내 학생식 당 이용 실태 및 급식서비스 수준을 조사$\cdot$분석하고 컨조인트 분석기법을 이용하여 가상 학생식당의 주요 속성에 대한 고객의 효용수준을 파악함으로써 신규 학생식 당의 계획 단계에서 중점을 두고 논의해야 할 필수요소를 도출하고 신규 학생식당의 모델을 제시하고자 하였다. 학생들의 학생식당 이용실태 분석 결과, 주당 평균 3.4회 학생식당을 이용하고 있었고, 이용 이유는 거리가 가깝고, 가격이 저렴하며 신속하게 식사를 해결할 수 있기 때문이었다. 급식서비스에 대한 전반적인 만족도$(2.77\pm0.82)$와 지불한 가격에 대해 인지되는 급식의 질인 가치 $(2.68\pm0.78)$ 모두 불만족하고 있는 상황이었다. 급식서비스의 12가지 세부 속성에 대한 인식도 조사 결과, 신속한 배식과 식당 운영시간, 가격, 식사량에 대해서는 비교적 수행 수준이 보통 이상으로 평가하였으나, 고객 불만사항 처리나 식당 시설 및 분위기에 대해서는 상당히 불만족하고 있는 것으로 나타나 이에 대한 개선이 절실한 것으로 사료되었다. 신규 학생식당 모델 도출을 위한 컨조인트 분석 결과, 급식서비스의 4가지 속성이 상충하는 상황에서 고객은 가격$(37\%)$, 분위기$(30\%)$, 음식$(22\%)$, 거리$(11\%)$ 순으로 중요하게 여기고 있었으며, 8가지의 가상급식소 프로파일 중에서 '프로파일 2', 즉 $6\~10$분 정도의 거리에 위치하고 여유롭고 편안한 분위기에서 4가지 정도의 반찬과 함께 후식을 2,000원 정도의 가격으로 판매되는 식사가 제공되는 급식소가 조사대상 대학교의 현재 여건에서 제안할 수 있는 신규 학생식당의 모델로 결론지어졌다. 본 연구 결과에서 도출된 이상적인 급식소 모델이 현장에 적용되어 새로운 급식소가 개소된다면 고객의 요구도가 적극 반영된 급식소 특성으로 인하여 현재 제기되고 있는 급식서비스에 대한 불만을 감소시키는 동시에 고객 만족을 꾀할 수 있으리라 사료된다. 또한 신규급식소에서 일정기간의 급식서비스를 제공한 후, 급식서비스에 대한 고객의 평가가 실시되어 현재의 연구결과와 비교된다면 본 연구에서 제안한 급식소 모델의 효과성도 평가될 수 있을 것으로 여겨진다. 덧붙여 고객의 평가 수준이 낮았던 급식서비스 속성의 개선이 함께 동반된다면 현재 급식소의 급식서비스 질 개선을 통한 고객 만족도의 증진이 가능하리라 본다.

• 가정과삶의질연구
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• 제29권3호
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• pp.23-41
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• 2011

The purpose of this study is to explore social supports for elderly housing and their residential lives in small cities along rural counties of the United States and Canada, and suggest future implications for age-concentrated rural villages in Korea. In this study, five small and medium cities in non-metropolitan counties of California and Ontario province were visited and elderly residents and service experts were interviewed about their perceptions of community integrated social support networks for senior residences. The senior housing complexes were built due to influx of both metropolitan and rural residents seeking warm localities, traffic connections, business purposes in active production areas. and leisure attractions. There are five main social support networks for senior housing issues in these areas. First, the areas are claimed for senior zones and accordingly health industries are encouraged by local authorities. Second, the community is homogeneously constructed as a senior friendly environment and include features such as an RV park and mobile cottages. Third, senior-helping seniors are offered active work through golf-cluster active retirement communities. Fourth, traditional theme production camps are mobilized by the elderly workers. Lastly, an information system is maintained for screening volunteers and for senior abuse prevention. On the other hand, residential lives are occasionally negatively influenced by unbalanced concentrations of elderly facilities such as nursing stations and funeral homes. For the future of Korean rural elderly policies, suggestions are made as follows: first, an integrated urban and rural township that contains attractive places for early retiring people who seek a warm atmosphere in later life needs to be constructed. Second, an integrated model retirement village of urban and rural retirement life needs to be initiated as a measure of evaluating the adaptation process of movers in senior concentrated zones. Third, a cooperation system among governmental ministries needs to be formed with the long- term goal of establishing a traditional rural town of independent housing districts and medical facilities in rural areas. Fourth, productive and active lifestyles need to be maintained as the local community and government develop successful retirement rural villages, by limiting the expansion of nursing related facilities. Finally, generation integrated visiting welfare programs and services need to be further developed for the housing areas especially in the winter, when social integration and activity are relatively low.

• 한국가스학회지
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• 제19권2호
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• pp.74-82
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• 2015

최근 화석연료의 사용증가에 따라 대량으로 배출되는 이산화탄소는 지구 온난화 현상을 일으키는 온실가스 중 하나로 지정되어 국제협약을 통하여 온실가스의 배출을 저감하도록 규제하고 있다. 본 연구에서는 이산화탄소를 저감하는 방법 중의 하나로, 3세대 바이오매스 생산시스템인 해조류를 활용한, 지속가능한 신 개념의 FPSO로서 해상환경 바이오매스 생산시스템의 최적구조를 설계하였다. 이를 위해 격자로 구조물을 설치한 후 해조류의 주변에 LED 조명을 비추어 성장을 최대화 시키는 시스템을 구상하였다. 그리고 기존 해조류의 성장자료를 통하여 해조류의 성장 모델을 만든 후 풍력발전기와 LED 조명을 포함하는 바이오매스 생산시스템을 모델링하여 최적화 도구인 GAMS 프로그램을 이용하여 본 시스템이 환경적 관점뿐만 아니라 경제성 측면에서도 타당성을 가질 수 있는 최적구조를 설계하였다. 또한 기존의 해상환경 바이오매스 생산시스템과 비교하여 최적구조를 제안하였다.

• 대한간호
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• 제36권3호
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• pp.49-69
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• 1997

The urgent needs to establish hospice care systems in Korea arise from the following reasons: 0) a drastic increase in chronically ill patients with the increase of aged population: (2) rapid changes in living environment from the traditional habitation (e. g., Many Koreans living in apartment complexes, which is the most popular form of modern residence in recent years, prefer to die in the hospital.): the overall increase in patients with advanced cancer: (4) recent trends in early discharge of terminally ill patients from the limited hospital facilities to accomodate other medical insurance beneficiaries; (5) easy acceptance of euthanasia owing to the recent social atmosphere that belittles the dignity of human life; (6) medical and nursing care of AIDS patient in terminal stage; (7) and the problem associated with inhumane medical care system, overtreatment, and groundless fears against narcotics. Terminally ill patients were used to be treated in the hospital in the past. In these days, however, they are forced to have home cares with little assistance from the qualified medical personnel because of insufficient hospital facilities, which are even short for the need of emergency patients and provide priority cares to medical insurance beneficiaries with other acute problems. And yet, neither are there any administrative organizations nor systematic medical studies that deal with the level of terminally ill patient's need, their family's problems and resources of hospice care systems in Korea. Thus, most patients are not able to get appropriate medical care at the terminal stage of their lives. The objective of this study is to make comprehensive database for various hospice care organization currently in operation, link them through medical information system, and develop an easily accessible hospice care model that meets the need of most Korean people. Our survey results may be summarized as follows: Nationally there are 40 organizations that provide partial or full hospice care. However, these organizations are not linked to any formal medical service network. Furthermore, the objective of hospice care, care principles, personnel with appropriate training, educational programs, standard for care, costs, consulting service to patients' family members, the extent of medical care from professional staff members, status of hospice facility, and management of those institutions are neither clearly defined nor organized compared to the international hospice care standards. The surveys on patients of terminal stage. grouped in hospice and non-hospice care patients. reveal what they want visiting nursing care to help their pain control. psychological. social and spiritual demands. While the more than 90% of hospice care patients want to reduce their pains. the non-hospice care patients. in addition to their desire for pain control. demanded more psychological. social and spiritual helps as well. The results of this research could be utilized to 0) define the standard of hospice care. (2) provide the guidance for hospice medical care costs. (3) establish the database of hospice care systems. (4) develop softwares. (5) build communication network through Medinet. and (6) provide an organized visiting home nursing care system. These information should be a valuable resource to many medical staffs who are involved in cancer therapy. nursing care. and social welfare programs.