• Nuclear Engineering and Technology
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• 제54권6호
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• pp.2077-2083
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• 2022

In the unlikely event of core disruptive accident in sodium cooled fast reactors, the reactor containment building would be bottled up with sodium and fission product aerosols. The behavior of these aerosols is crucial to estimate the in-containment source term as a part of nuclear reactor safety analysis. In this work, the evolution of sodium aerosol characteristics (mass concentration and size) is simulated using HAARM-S code. The code is based on the method of moments to solve the integro-differential equation. The code is updated to FORTRAN-77 and run in Microsoft FORTRAN PowerStation 4.0 (on Desktop). The sodium aerosol characteristics simulated by HAARM-S code are compared with the measured values at Aerosol Test Facility. The maximum deviation between measured and simulated mass concentrations is 30% at initial period (up to 60 min) and around 50% in the later period. In addition, the influence of humidity on aerosol size growth for two different aerosol mass concentrations is studied. The measured and simulated growth factors of aerosol size (ratio of saturated size to initial size) are found to be matched at reasonable extent. Since sodium is highly reactive with atmospheric constituents, the aerosol growth factor depends on the hygroscopic growth, chemical transformation and density variations besides coagulation. Further, there is a scope for the improvement of the code to estimate the aerosol dynamics in confined environment.

• 한국콘텐츠학회논문지
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• 제21권12호
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• pp.375-383
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• 2021

COVID-19로 인해 사람들은 외출과 모임 자제로 온라인 쇼핑, 온라인 여행, 화상회의 등 새로운 라이프 스타일을 구축하고 있다. 이러한 급격한 사회의 변화는 새로운 문제들을 야기시킴과 동시에 기존의 문제들을 심화시키고 있다. 특히 온라인 소비가 크게 증가함에 따라 생활물류산업에서는 교통체증, 대기오염, 배송기사의 과중한 업무 등이 심화되고 있으며 대면배송이 새로운 문제점으로 나타나고 있다. 4차 산업혁명의 등장으로 드론에 인공지능, 자율주행 등을 활용한 무인 배달이 기존 생활물류산업의 대체산업으로 떠오르고 있으나 드론의 비행에 따른 물류시설의 공간과 추가적인 물류부지 확보가 해결되어야 하는 새로운 문제점으로 나타난다. 따라서, 기존의 문제들과 새롭게 생겨난 문제들을 해소할 수 있는 드론을 위한 물류시설의 공간으로 기존 운수 사업인 지하철을 활용하여 물류 이동과 보관, 배송 등과 같은 부가적인 서비스를 연계하고자 한다.

• Nuclear Engineering and Technology
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• 제54권9호
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• pp.3440-3447
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• 2022

The accuracy of the photoatomic cross-section data is of great importance in the field of radiation protection, particularly in the characterization of radiation shielding materials. With the release of the latest and probably the most accurate photoatomic data library, EPDL2017, the need to re-evaluate all the existing and already established mass attenuation coefficients (MACs) of all radiation shielding materials arises. The MACs of several polymers, alloy-based, glasses, and building materials used in a nuclear medicine facility were investigated using the EPDL2017 library embedded in EpiXS software and were compared to MACs available in the literature. The relative differences between MAC_EpiXS and MACXCOM were negligible, ranging from 0.02% to 0.36% for most materials. However, for material like a glass comprising of elements Te and La evaluated near their corresponding K-edge energies, the relative differences in MACs increased up to 1.46%. On the other hand, a comparison with MACs calculated based on EPDL97 (a predecessor of EPDL2017) revealed as much as a 6.61% difference. Also, it would seem that the changes in MACs were more evident in the materials composed of high atomic number elements evaluated at x-ray energies compared to materials composed of low atomic number elements evaluated at gamma-ray energies.

• 한국컴퓨터정보학회논문지
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• 제28권3호
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• pp.149-157
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• 2023

본 연구는 공연시설 내 공연장 무대공간에서 위기상황에서 피난 시 공연예술종사자가 반입구 및 공연자통로를 적극적으로 활용하는 것을 제안하는 것이 목적이다. 먼저 공연장 안전과 관련된 제도를 분석하고 무대피난 유형을 건축법 내 객석 피난 기준을 적용하여 A, B, C, D 형태로 분류하였다. 둘째, 측정자료를 바탕으로 통계자료를 정리하고 각 형태의 특징을 정리하였다. 셋째, 무대공간에서 피난 경로의 피난 안전성을 평가하기 위해 네트워크 신뢰도 측정방법을 차용하였다. 그리고 무대중심에서 반입구 방향, 공연자 출입문 방향이 피난에 유리함을 정량적으로 확인하였다. 본 연구에서 피난형태에 따른 피난의 유리함(A(0.1274)>B(0.1228)>C(0.0487))을 구분할 수 있었다. 이러한 결과는 무대피난 안전성을 향상과 무대피난의 기초자료로 활용될 수 있기를 기대한다.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.732-737
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• 2009

Due to various project delivery methods and the complexity of construction projects in the construction industry, developing the framework of construction management for critical, highly complex projects in the construction industry has become problematic. Currently, a set of construction manuals play a pivotal role in planning and managing construction projects as subcontractors try to complete their scope of work according to the instructions of a general contractor. It is challenging for general contractors to write a construction management procedure manual to cover various types of project delivery methods and construction projects. In construction, the construction procedure manuals describe specific actions to be taken through the project. In reality a few contactors own such manuals and their construction schedules include more construction operation activities. Thus, it is hard to estimate the workload and productivity of construction managers because the manual and the schedule do not present the amount of management efforts required to complete a project. This paper proposes a framework to present construction management tasks according to project delivery methods which can be applied to various construction projects. Actions for management tasks were mapped and were integrated with construction activities throughout the project life cycle. The framework can then be used to give specific instructions to project participants, collect management actions, and replicate management actions throughout the project life cycle. The framework can also be can used to visualize complete construction project to analyze and manage construction management activities in each phase of a project in order to enhance productivity and efficiency. The studies of existing construction manuals were carried out to identify construction managers' responsibilities. An artificial intelligence program, CLIPS (C-Language Integrated Production System) was used to search for appropriate actions for impending tasks from a set of predefined actions to be performed for a given situation. The framework would significantly help construction managers to understand interrelations among management tasks or actions within a project. Furthermore, the framework can be embedded into Building Information Modeling (BIM) or Facility Management Systems (FMS) so that designers and constructors would execute constructability review before construction begins.

• 인터넷정보학회논문지
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• 제24권2호
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• pp.37-45
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• 2023

4차 산업혁명에 맞춰 스마트팩토리 구축을 위한 설비보전 기술들이 관심을 받으며 고도화되고 있다. 또한 스마트팩토리에 이어 스마트팜, 스마트 양식장에도 기술이 접목되고 있다. 그중에서도 순환여과식 양식장의 경우는 수조의 안정적인 수질 환경을 위해 물을 순환하는 펌프 모터가 존재한다. 순환여과식 양식장 펌프 모터 보전 활동은 예방 정비와 진동센서에서 취득된 데이터를 기반으로 수행한다. 예방정비는 사전계획 이전에 일어나는 이상에 대해서는 대처할 수 없으며 진동센서는 외부 환경에 영향을 받는다. 본 논문에서는 소음, 온도, 진동센서에 비해 외부 환경의 영향을 적게 받는 전류 센서를 통해 수집된 데이터를 기반으로 펌프 모터 이상 감지에 있어 Python 오픈소스인 ADTK를 활용하는 이상 감지 알고리즘을 제안한다.

• 한국농촌건축학회논문집
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• 제24권2호
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• pp.21-28
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• 2022

Focusing on the creation of a new han ok, especially a mid-rise hybrid-structured Han-ok, this study proposes a middle-rise (four-story) Han-ok on one and two lots located in Seoun-dong, the existing Han-ok intensive housing site in downtown Cheongju. 1) In terms of layout and function, according to the existing L-shaped Han-ok corresponding to the road and the direction, the parking lots and shops on the 1st floor, the business facility on the 2nd floor, the Han-ok on the 3rd and 4th floors are placed. There are yards, open roof yards, and semi-open Daecheong(大廳, main hall), which can be shared by residents. 2) In terms of structure and form, one or two floors (some 3 floors) are 5.4m square and 5.4×6.6m modules of the RC(Reinforced Concrete) group, and the upper floor reflects the 2.7m module, size and shape of the existing Han-ok. By extending the outer wall of the RC group in the lower floors (1st to 3rd floors) to the wooden exterior of the upper floors (2nd to 4th floors), it is attempted to avoid the awkward appearance of the RC group being exposed to wooden structures. And it is also attempted to reflect the wooden shape and design elements through the elevation elements such as horizontal windows, corner windows, picture frames, and vertical slits. 3) In environmental control and facilities, it is attempted to smooth the ventilation of the building by forming a vertical upward airflow from the dark space of the low floor to the positive of the upper floor. This doubles the effect through a vertical rise of cold air generated in a narrow alleyway, piloti parking lot, and the various voids. In addition to the Daecheong and Numaru(loft) of Han ok, the rooftop yard, the terrace, and the balcony, horizontal natural ventilation is generated through divided doors and transom windows.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.1256-1263
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• 2022

With the advent of the Fourth Industrial Revolution, the amount of energy used in buildings has been increasing due to changes in the energy use structure caused by the massive spread of information-oriented equipment, climate change and greenhouse gas emissions. For the efficient use of energy, it is necessary to have a plan that can predict and reduce the amount of energy use according to the type of energy source and the use of buildings. To address such issues, this study presents a model embedded in a digital twin that predicts energy use in buildings. The digital twin is a system that can support a solution of urban problems through the process of simulations and analyses based on the data collected via sensors in real-time. To develop the energy use prediction model, energy-related data such as actual room use, power use and gas use were collected. Factors that significantly affect energy use were identified through a correlation analysis and multiple regression analysis based on the collected data. The proof-of-concept prototype was developed with an exhibition facility for performance evaluation and validation. The test results confirm that the error rate of the energy consumption prediction model decreases, and the prediction performance improves as the data is accumulated by comparing the error rates of the model. The energy use prediction model thus predicts future energy use and supports formulating a systematic energy management plan in consideration of characteristics of building spaces such as the purpose and the occupancy time of each room. It is suggested to collect and analyze data from other facilities in the future to develop a general-purpose energy use prediction model.

• 한국재난정보학회 논문집
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• 제19권4호
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• pp.882-896
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• 2023

연구목적: 국가산업단지 공장시설물이 보유한 내진설계의 잠재적 위험과 안전지도 및 점검의 미비점을 효과적으로 향상시킬 수 있는 안전관리 및 내진보강대책 마련을 목적으로 한다. 연구방법: 본 연구에서는 국가산업단지의 지진재난 대비 안전관리 현황 및 관리체계 등 지진재난 안전관리 전반에 관한 조사·분석을 통해 문제점 및 개선방안을 도출하였고, 국가산업단지 내 입주기업체 내진설계 실태조사를 실시하여 시설유형과 구조적 특성에 기반한 개선방안을 제시하였다. 연구결과: 결론적으로 국가산업단지 지진재난 대비 안전관리 및 내진보강에 대한 문제점을 정리하여 4가지 유형별(내진성능 평가 및 관련 제도 보완, 입주기업 및 지자체 권한, 내진보강 및 안전관리 지원대책, 조직의 역량강화)로 개선방안을 도출하였다. 결론: 이를 기반으로 국가산업단지 입주기업이 지진재난을 대비하여 추진해야 하는 내진보강 대책을 마련하였으며, 각 대책별 세부적인 방안을 제시하였다.

• 산업융합연구
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• 제22권9호
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• pp.157-168
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• 2024

본 연구는 Q방법론을 활용하여 장애인거주시설에서 생활하는 장애인의 체육활동 활성화 방안에 대해 인식 유형을 파악하고 이를 바탕으로 시사점을 도출하기 위한 것이다. 이를 위해 먼저 선행연구, 현장 및 특수체육 전문가를 대상으로 개방형 설문조사를 실시하여 총 25개의 Q진술물을 작성하였다. 이후 시설 종사자 22명을 대상으로 Q분류를 실시하였고, 그 결과를 PQ method 2.3.5 프로그램을 이용하여 분석하였다. 분석결과는 정부의 지원형, 장애인체육시설 확충, 공감대 형성 총 3가지 유형으로 도출되었다. 장애인거주시설 내 장애인의 체육활동 활성화를 위해서는 정부의 지원을 통한 체육활동에 적극적으로 참여할 수 있는 체육시설이 확충되어야 할 것과 장애인의 체육활동에 대한 사회구성원들의 인식 개선도 중요하다는 것을 확인할 수 있었다. 이러한 연구결과는 향후 장애인복지시설에서의 체육활동 활성화를 위한 정책자료 제공 및 방향 설정에 기초자료를 제시하였다는 데 그 의의가 있다.