IEC 60364의 접지방식에 기반한 안전성 평가 시험장치의 모델링 및 구현에 관한 연구

김순식(Soon-Sik Kim),한병길(Byeong-Gill Han),이후동(Hu-Dong Lee),페레이라 마리토(Marito Ferreira),노대석(Dae-Seok Rho) 한국산학기술학회 2021 한국산학기술학회논문지 Vol.22 No.6

국내 접지방식은 2021년부터 IEC 60364에서 제시하는 접지방식을 새롭게 채택하고 있다. 이 접지방식은 인체접촉사고 발생 시, 접촉전압과 통과전류에 대한 특성이 다양하게 나타날 수 있어, 인체에 대한 안전성 평가가 구체적으로 요구되고 있다. 또한, 한국전기안전공사나 대한전기협회에서 IEC 60364의 접지방식에 대한 안전기술 교육을 부분적으로 수행하고 있지만, 안전성을 평가할 수 있는 시험장치가 미흡하여, 전기안전관리자에 대한 교육이 어려운 실정이다. 따라서, 본 논문에서는 IEC 60364의 접지방식별 안전성 평가를 수행할 수 있는 시험장치를 모델링하고, 이를 바탕으로 시험장치를 구현한다. 즉, 전력계통 상용해석 프로그램인 PSCAD/EMTDC를 이용하여, 계통 전원부, 접지방식별 시험장치부, 보조장치부로 구성된 안전성 평가 시험장치의 모델링을 제시하고, 계통전원부, TT접지방식 시험장치부, TN-S접지방식 시험장치부, 모니터링부로 구성된 안전성 평가 시험장치를 구현한다. 상기의 모델링과 시험장치를 이용하여, TT접지방식과 TN-S접지방식의 인체 안전성 특성을 분석한 결과, TT접지방식의 경우 고장점 임피던스가 0[Ω], 10[Ω], 100[Ω]에서 인체 통과전류는 각각 104[㎃], 87.4[㎃], 35.5[㎃]가 산정되었고, TN-S접지방식의 경우 54.9[㎃], 4.1[㎃], 0.4[㎃]가 산정됨에 따라, TN-S접지방식이 TT접지방식에 비하여 감전에 대한 보호가 우수함을 알 수 있고, 저압수용가에서 사용 중인 TT 접지방식에서 TN-S 접지방식으로 전환하면 감전에 대한 보호성능을 향상시킬 수 있음을 알 수 있었다. A novel grounding system, which is presented in IEC 60364, has been adopted since 2021. A safety evaluation for the hu㎃n body on the grounding system is required due to the various characteristics of the touch voltage and current passing when the human body experiences an electric shock. The Korea Electrical Safety Corporation (KESCO) and Korea Electric Association (KEA) have been conducting a safety technical education on the grounding system. On the other hand, it is difficult to instruct the electrical safety manager because of a lack of safety evaluations for the test equipment on the grounding system. Therefore, this paper modeled and implemented a test device for a safety evaluation depending on the grounding system of IEC 60364. Namely, this paper presents the modeling of the test device for a safety evaluation using PSCAD/EMTDC S/W, which is composed of an AC grid section, s test device section on the grounding system, and a sub-device section. This paper implemented a test device for safety evaluation, which consisted of an AC grid section, TT grounding system section, TN-S grounding system section, and monitoring section. From the simulation and test results with the safety characteristics of the hu㎃n body in the TT and TN-S grounding system, when the fault impedances are 0[Ω], 10[Ω], and 100[Ω], the currents passing through the hu㎃n body in the TT grounding system are 104[㎃], 87.4[㎃], and 35.5[㎃], respectively. The corresponding currents in the TN-S grounding system are 54.9[㎃], 4.1[㎃], and 0.4[㎃], respectively. Based on the results, the protection performance for an electric shock to the hu㎃n body in the TN-S system is better than the TT system. This can be improved when the existing grounding system is changed from the TT system to the TN-S system.

아래턱뼈 계측을 통한 한국인의 체질인류학적 특징 및 남녀판별함수 분석

허경석,고기석,정한성,강민규,최병영,김희진 대한췌담도연구회 2000 대한췌담도연구회지 Vol.5 No.4

회수수에 당류계 안정화제를 처리한 시멘트 모르터의 특성

金虎林,우종완,한민철,류현기,한천구 대한건축학회 2004 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.24 No.1(구조계)

In this paper, fundamental properties of cement mortar using recycled water with stabilizing agent are discussed in order to investigate the applicability of recycled water. Stabilizing agent content, solid contents and open time are varied in this paper. For fresh mortar properties, highest fluidity with 0.15% of stabilizing agent was observed and air content was increased with an increase in stabilizing agent contents. Solid contents and open time of recycled water had nothing to do with fluidity and air content loss. Little difference in setting time was found with the presence of stabilizing agent and without, while it was accelerated with an increase in open time and solid content. For strength properties, the highest strength value was observed at 0.15% of stabilizing agent. An increase in solid contents resulted in an enhancement of strength, while strength decreased with an increase in open time and elapse of age. Drying shrinkage exhibited a reduction with an increase in stabilizing agent contents and open time. From the present paper, the combination of 0.15% of sacharic based stabilizing agent, 3% of solid content and 1day of open time is found to be an optimal condition to perform effectively.

효소적 작용과 신선 채소의 품질 변화

정호철,이상한,정신교 慶北大學校農業科學技術硏究所 2007 慶北大農學誌 Vol.25 No.-

The several enzymes reaction which involve the quality change of fresh vegetables, such as chlorophylase, polyphenol oxidase, lypoxygenase, C-S-Iyase, myrosinase and enzymes related lignification were reviewed. Numerous enzyme reaction continuously proceeds to the deterioration of vegetables after harvest due to the respiration and biochemical metabolism reaction, especially in case of physical injuring. It is extremely important to inhibit and to control these enzyme reaction in order to maintain the organoleptic and nutritional quality of fresh vegetables.

국내 레미콘사의 부순모래 사용실태 조사

김기훈,金虎林,金光華,윤기원,한천구 대한건축학회 2004 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.24 No.1(구조계)

Crushed sand is made by crushing the rock artificially. With the wide shortage of natural fine aggregates at all regions in Korea. crushed sand has been increasingly consumed as a alternative aggreagtes of natural sand. But there is insufficient information related to the actual situation on the produce. quality and manufacturing company of crushed sand. In this paper. survey is performed in order to know actual consumption situation of crushed sand through ready mixed concrete company in domestic. The remicon companies using crushed sand were estimated with 55%. According to the using method of crushed sand. most remicon company used fine aggregates by mixing natural sand and crushed sand. It is found that natural sand is replaced by crushed sand by about 20~50%. For quality problems in using crushed sand. grain shape. grade and fine particles shall be improved to meet the quality requirement of remicon and wide application. Therefore. it is found that quality improvement of crushed sand is required.

회수수에 처리되는 당류계 안정화제의 혼입률 변화가 콘크리트의 품질에 미치는 영향

文學龍,金虎林,우종완,한민철,한천구 대한건축학회 2004 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.24 No.1(구조계)

The objective of present paper is to investigate the engineering properties of concrete using recycling water incorporating saccharic based stabilizing agent in order to improve qualities of concrete in the region of normal strength and high strength. According to test results, fluidity and air content do not exhibit significant difference with an increase in stabilizing agent contents. Bleeding was not observed at 30% of W Ie, regardless of stabilizing agent contents, nonetheless, concrete with stabilizing agent of 0.15% was observed to occur the least bleeding at 40 and 50% of W IC. For setting time, although presence of recycled water accelerates setting time, setting time shows to be retarded gradually with an increase in stabilizing agent content. For compressive strength, use of stabilizing agent enhanced compressive strength of concrete compared with that of concrete without stabilizing agent. In the side of strength enhancement, adequate dosage of stabilizing agent is found to be 0.15%. As dosage of stabilizing agent increased above 0.15%, drying shrinkage exhibited a tendency to decrease.

Direct Synthesis of H2O2 over Ti-Containing Molecular Sieves Supported Gold Catalysts: A Comparative Study for In-situ-H2O2-ODS of Fuel

Han Zhang,Guangliang Liu,Haiyan Song,Chunxia Chen,Fuqin Han,Ping Chen,Zhixi Zhao,Shaozheng Hu 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.10

Direct synthesis of H2O2 and in situ oxidative desulfurization of model fuel over Au/Ti-HMS and Au/TS-1 catalysts has been comparatively investigated in water or methanol. Maximum amount (82%) of active Au0 species for H2O2 synthesis was obtained. Au/Ti-HMS and Au/TS-1 exhibited the contrary performances in H2O2 synthesis as CH3OH/H2O ratio of solvent changed. H2O2 decomposition and hydrogenation in water was inhibited by the introduction of methanol. Effect of O2/H2 ratio on H2O2 concentration, H2 conversion and H2O2 selectivity revealed a relationship between H2O2 generation and H2 consumption. The highest dibenzothiophene removal rate (83.2%) was obtained over Au/Ti-HMS in methanol at 1.5 of O2/H2 ratio and 60 oC. But removal of thiophene over Au/TS-1 should be performed in water without heating to obtain a high removal rate (61.3%). Meanwhile, H2 conversion and oxidative desulfurization selectivity of H2 were presented.

A Study on the X-lai-X-qu Construction in Modern Mandarin Chinese : A Cognitive Semantics Approach

Han Hu,Youngiu Choi 한국언어과학회 2021 언어과학 Vol.28 No.2

The construction X-lai-X-qu ‘X-come-X-go’ is widely used in modern Mandarin Chinese and it has attracted researchers’ attention because the construction has diverse meanings when various types of words occur in the X position. Previous studies have explored the construction and identified the meaning of this construction as ‘repetition’(Li, 2002; Zeng, 2008; Zhou, 2017; Lu, 2018). Lu (2018), for example, has examined the meaning relatedness between variants of the construction from a cognitive perspective. However, the focus of Lu’s study is limited to meaning extensions of X-lai-X-qu only when verbs take the X positions. Other variants where pronouns, nouns and adjectives occur in the X position have not been adequately addressed. For more comprehensive analysis, this paper examines all the different variants of the construction and analyzes construction X-lai-X-qu from the perspective of cognitive semantics and concludes that they are all related in meanings through metaphor and metonymy.

Poster Session 2 : Oral Presentation ; Neurobiology : H7 and Genistein as pharmacological agent for inhibition of IL-1β production in neuro-inflammation

( Hu Nan Sun ),( Wan Fang ),( Mei Hua Jin ),( Ying Hao Han ),( Sun Uk Kim ),( Sang Han Lee ),( Nam Soon Kim ),( Cheol Hee Kim ),( Dong Seok Lee ) 한국생화학분자생물학회 (구 한국생화학회) 2005 62회 KSBMB Annual Meeting in 2005 Vol.- No.-

Matching Composite Sketches to Face Photos: A Component-Based Approach

Hu Han,Klare, B. F.,Bonnen, K.,Jain, A. K. IEEE 2013 IEEE transactions on information forensics and sec Vol.8 No.1

<P>The problem of automatically matching composite sketches to facial photographs is addressed in this paper. Previous research on sketch recognition focused on matching sketches drawn by professional artists who either looked directly at the subjects (viewed sketches) or used a verbal description of the subject's appearance as provided by an eyewitness (forensic sketches). Unlike sketches hand drawn by artists, composite sketches are synthesized using one of the several facial composite software systems available to law enforcement agencies. We propose a component-based representation (CBR) approach to measure the similarity between a composite sketch and mugshot photograph. Specifically, we first automatically detect facial landmarks in composite sketches and face photos using an active shape model (ASM). Features are then extracted for each facial component using multiscale local binary patterns (MLBPs), and per component similarity is calculated. Finally, the similarity scores obtained from individual facial components are fused together, yielding a similarity score between a composite sketch and a face photo. Matching performance is further improved by filtering the large gallery of mugshot images using gender information. Experimental results on matching 123 composite sketches against two galleries with 10,123 and 1,316 mugshots show that the proposed method achieves promising performance (rank-100 accuracies of 77.2% and 89.4%, respectively) compared to a leading commercial face recognition system (rank-100 accuracies of 22.8% and 52.0%) and densely sampled MLBP on holistic faces (rank-100 accuracies of 27.6% and 10.6%). We believe our prototype system will be of great value to law enforcement agencies in apprehending suspects in a timely fashion.</P>