• KIEAE Journal
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• 제5권1호
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• pp.11-18
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• 2005

The optimized HVAC system design in tall buildings enable owners to save unnecessary energy consumption and residents to have comfort environments. The purpose of this study is to develop design process for optimized HVAC system design in tall buildings. As basic researches, literature researches and case studies of HVAC system design in tall buildings were performed. Survey was processed among expert in the field and key considerations on HVAC system design were drew as conclusions. With these conclusions, studies were performed on effects of wind velocity, outdoor air temperature, and solar radiation that are main factors of load calculation in tall buildings. Finally, air-tightness and stack effect were analyzed and estimated by literature studies, field measurements and computer simulations.

• Journal of Advanced Marine Engineering and Technology
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• 제11권1호
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• pp.63-71
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• 1987

The measuring of acoustic intensity has been investigated by many researchers and practicians during the last several decades. But due to the lack of measurement accuracy, they have had no practical use. In recent years, the two microphone acoustic intensity method has been developed by the advancement of FFT analysis technique and the digital data processing equipment. This new method of using two microphones gives informations on the noise source survey and the acoustic power of sound radiation source without the anechoic room. In this paper, theoretical formulae for the two microphone acoustic intensity method and the sound transmission loss are checked. The obtained results for the acoustical enclosure of gas heat pump were compared with the classical field incidence mass law. The surface vibration modes for a panel of enclosure were also estimated.

• 방사성폐기물학회지
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• 제18권3호
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• pp.347-354
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• 2020

Site characterization for decommissioning Kori Unit 1 is ongoing in South Korea after 40 years of successful operation. Kori Unit 1's containment building is assumed to be mostly radioactively contaminated, and therefore radiation exposure management and detailed contamination investigation are required for decommissioning and dismantling it safely. In this study, site-specific Derived Concentration Guideline Levels (DCGLs) were derived using the residual radioactivity risk evaluation tool, RESRAD-BUILD code. A conceptual model of containment building for Kori Unit 1 was set up and limited occupational worker building inspection scenario was applied. Depending on the source location, the maximum contribution source and exposure pathway of each radionuclide were analyzed. The contribution of radionuclides to dose and exposure pathways, by source location, is expected to serve as basic data in the assessment criteria of survey areas and classification of impact areas during further decommissioning and decontamination of sites.

• 한국IT서비스학회:학술대회논문집
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• 한국IT서비스학회 2008년도 추계학술대회
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• pp.405-407
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• 2008

원자력발전소는 안전성이 가장 중요시되는 국가 기간 설비로서 해마다 over-haul 기간 동안에 중요 설비에 대한 안전성 검사를 수행한다. 그러나 이 약 한달 정도의 over-haul 동안에 모든 중요설비에 대한 진단 작업을 수행하기에는 시간이 턱없이 모자라는 관계로 몇년의 주기로 나누어 검사 계획에 따라 검사 대상 설비를 나누어 검사하는 실정이다. 원자력발전소의 중요 설비에 대한 감시진단은 상시 이루어져야 가장 이상적이나 수많은 유선센서를 이용한 방법은 문제점이 많다. 따라서 무선센서가 사용되고 있는 추세이나 무선센서에 대한 전력 공급 문제가 발생하고 있는 실정이다. 원자력발전소 내부에서는 방사선이라는 특별한 에너지원이 존재하는데, 본 논문에서는 이 에너지원을 이용하여 무선센서의 전력 수급을 해결하기 위한 원자력전지의 개발에 대하여 언급한다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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• pp.222-226
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• 2009

The parts of building which has the most influence on thermal load are skins, outer walls and windows. Among them, window is the worst weak point of building even if it has many advantage of solar radiation gain than other parts. The present time, many researches on various performance of window and many types of system-window are being made. This study evaluates thermal performance of tilt & sliding system window by simulation program Therm 5.2 and Window 5.2. After making a sample model improving it's thermal weak point, this study evaluates real thermal performance of system window. As a result, this study understands manufacture ability condition of domestic company and proposes a research plan of system window.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2012년도 학술발표회
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• pp.336-339
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• 2012

Accurate forecasting of pan evaporation (PE) is very important for monitoring, survey, and management of water resources. The purpose of this study is to develop and apply Kohonen self-organizing feature maps neural networks model (KSOFM-NNM) to forecast the daily PE for the dry climate region in south western Iran. KSOFM-NNM for Ahwaz station was used to forecast daily PE on the basis of temperature-based, radiation-based, and sunshine duration-based input combinations. The measurements at Ahwaz station in south western Iran, for the period of January 2002 - December 2008, were used for training, cross-validation and testing data of KSOFM-NNM. The results obtained by TEM 1 produced the best results among other combinations for Ahwaz station. Based on the comparisons, it was found that KSOFM-NNM can be employed successfully for forecasting the daily PE from the limited climatic data in south western Iran.

• Journal of Radiation Protection and Research
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• 제35권3호
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• pp.111-116
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• 2010

진단을 위한 엑스선검사는 의료분야에서 전리방사선을 가장 많이 사용하고 있으며 인공 방사선피폭중 가장 높은 비율을 차지하고 있다. 우리나라에서도 진단 엑스선검사에 의한 의료피폭은 전체 방사선 피폭 중 17.4%를 차지하고 있으며 인공방사선피폭 중에서는 92%를 차지하고 있다. 두부진단을 위한 엑스선 촬영 횟수도 2007년의 경우에는 111,567건으로서 2004년 이후 매년 3% 정도의 증가 추세를 나타내고 있다. 따라서 환자선량 권고량을 국내의료기관 실정에 맞도록 설정하여 두부촬영시 환자가 받는 방사선량을 줄이고 환자의 방사선 방어를 최적화 하는 것이 필요하다. 본 논문에서는 전국 114개 의료기관에서의 두부 촬영시 피폭되는 방사선량을 인체팬텀과 유리선량계를 사용하여 측정하고 환자선량권고량(DRL, Diagnostic Reference Level)을 확립하였다. 이 결과에 따라 두부 후전면 촬영에서의 환자선량 권고량은 2.23 mGy이며, 이는 세계보건기구, 국제원자력기구 등 국제기구가 권고하는 선량 5 mGy 보다 낮았으며, 두부 측면찰영에서의 환자선량 권고량인 1.87 mGy는 국제기구가 권고하는 선량 3mG 보다 낮았다.

• 한국식품저장유통학회지
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• 제24권1호
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• pp.27-35
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• 2017

본 연구는 면역저하 환자용 신선편의 채소류의 위생화를 위해 당근, 오이고추, 방울토마토, 파프리카를 모델식품으로 선정하여 다양한 흡수선량으로 엑스선 조사처리한 후 미생물학적, 이화학적, 관능적 품질 평가를 수행하였다. 당근과 오이고추의 경우 0.4 kGy, 방울토마토와 파프리카의 경우 0.2 kGy 이상의 흡수선량으로 엑스선 조사처리 시 멸균이 확인되었으며, 총 호기성세균 및 대장균군을 제외한 병원균들은 1 log 수준의 검출한계 이하로 나타났다. 모델식품에 접종된 E. coli. L. monocytogenes, S. Typhimyrium에 대한 엑스선의 D10값은 0.11-0.32 kGy로 나타나, 0.4 kGy의 흡수선량을 신선편의 채소류의 멸균을 위한 잠정적인 최소 흡수선량으로 설정하였다. 최대 0.6 kGy의 흡수선량으로 엑스선 조사처리된 신선편의 채소류에 대한 전체 선호도의 경우 7점 척도에서 모두 5.0 점 이상으로 나타나 이들의 관능적 품질이 수용 가능한 수준인 것으로 판단하였다. 또한, 암환자를 대상으로 엑스선 멸균처리(0.4 kGy)된 신선편의 채소류에 대한 선호도 설문조사에서 오이고추와 방울토마토, 파프리카의 경우 모든 항목에 대한 평균 선호도 점수는 5점 척도에서 모두 4.0점 이상으로 나타났다. 따라서 엑스선으로 멸균처리된 오이고추, 방울토마토, 파프리카는 면역력이 저하된 환자들을 위한 위생학적으로 안전한 신선편의 채소로 제공이 가능할 것으로 판단된다.

• Imaging Science in Dentistry
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• 제43권2호
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• pp.77-84
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• 2013

Purpose: This study aimed to provide comparative measurements of the effective dose from direct and indirect digital panoramic units according to phantoms and exposure parameters. Materials and Methods: Dose measurements were carried out using a head phantom representing an average man (175 cm tall, 73.5 kg male) and a limbless whole body phantom representing an average woman (155 cm tall, 50 kg female). Lithium fluoride thermoluminescent dosimeter (TLD) chips were used for the dosimeter. Two direct and 2 indirect digital panoramic units were evaluated in this study. Effective doses were derived using 2007 International Commission on Radiological Protection (ICRP) recommendations. Results: The effective doses of the 4 digital panoramic units ranged between $8.9{\mu}Sv$ and $37.8{\mu}Sv$. By using the head phantom, the effective doses from the direct digital panoramic units ($37.8{\mu}Sv$, $27.6{\mu}Sv$) were higher than those from the indirect units ($8.9{\mu}Sv$, $15.9{\mu}Sv$). The same panoramic unit showed the difference in effective doses according to the gender of the phantom, numbers and locations of TLDs, and kVp. Conclusion: To reasonably assess the radiation risk from various dental radiographic units, the effective doses should be obtained with the same numbers and locations of TLDs, and with standard hospital exposure. After that, it is necessary to survey the effective doses from various dental radiographic units according to the gender with the corresponding phantom.

• Journal of Radiation Protection and Research
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• 제28권4호
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• pp.327-335
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• 2003

The commercially available neutron survey meter, the REM500, which uses a tissue equivalent proportional counter (TEPC) and the self-constructed TEPC were used to determine the microdosimetric quantities of several neutron calibration fields at Korea Atomic Energy Research Institute (KAERI). Microdosimetric spectra, absorbed dose, dose equivalent as well as quality factor were derived and compared with several neutron fields which were produced by using the shadow objects to make neutron scattered and being used as a kind of realistic neutron calibration fields at KAERI. The response of REM500 as a function of mean energy was evaluated with these neutron fields using the counts measured and the predetermined reference value. The response of the self-made TEPC and the REM500 was compared using one of the neutron calibration filelds of a $^{252}Cf$ source. The reference quantities of scattered neutron calibration fields were determined using a Bonner Sphere (BS). The value of frequency-mean lineal energy, dose-mean lineal energy and quality factor of two $^{252}Cf$ sources (unmoderated and $D_2O$ moderated) were determined to check the differences in the reference neutron fields between KAERI and Pacific Northwest National Laboratory (PNNL, USA) and the results were in good agreement within 1%. It means that there is no big difference in dosimetric quantifies of neutron calibration fields of two laboratories.