• Title/Summary/Keyword: leakage point

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Analysis of Thermal Interrelation by Leakage Current in Open and Closed Statues (개방 및 밀폐상태에서의 누설 전류에 대한 열적 상관관계 분석)

  • Kim, Doo-Hyun;Kim, Sung-Chul;Park, Jong-Young;Choi, Seung-Ho;Lee, Jong-Ho
    • Fire Science and Engineering
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    • v.24 no.6
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    • pp.7-12
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    • 2010
  • This paper is aimed the measurement and estimation the thermal interrelation based on leakage current. The leakage models are analyzed by parameters in open and closed (Panel) states and with wood dust and rainwater, charcoal powder in leakage current occurred point. The thermal characteristic of open state that leakage current is inputted in 90 mA is higher in charcoal powder ($105^{\circ}C$) than in wood dust and rainwater ($88.8^{\circ}C$). Charcoal powder that is inputted in 110 mA shows high thermal characteristic ($238.6^{\circ}C$) and the thermal ($238.6^{\circ}C$) is caused by material strain of electrical wire insulation and Panel. The closed state in 90 mA is higher in charcoal powder ($250.6^{\circ}C$) than in wood dust and rainwater ($90.8^{\circ}C$). The open and closed state appear thermal characteristics of two times in charcoal powder than in wood dust and rainwater. The thermal data that are open and close states are used electrical fire investigation and thermal characteristic for Leakage current.

A Study on the Applicability of Levee Leakage Monitoring System Using Movable TDR Sensor (제방 누수 모니터링을 위한 이동식 TDR 센서의 적용성 평가)

  • Cho, Jinwoo;Choi, Bong-Hyuck;Cho, Won-Beom;Kim, Jin-Man
    • Journal of the Korean Geosynthetics Society
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    • v.13 no.3
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    • pp.1-10
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    • 2014
  • Several types of methods such as resistivity survey, ground penetration radar, etc are used for detection of levee leakage and according to the river design guidelines detection of levee leakage is performed by measuring the hydraulic conductivity of levee soil. But, the former can not verify the leakage point and degree of saturation, the latter is an after treatment method. Movable sensor, which is a high-tech TDR system developed since 2000, can obtain directly the dielectric constant profile covering the whole depth of levee. In this study, laboratory and field model experiments were carried out using movable TDR sensor in order to evaluate the applicability as detection system of levee leakage, As the result, movable TDR system has proven to be 3 times more sensitive to water contents than dry unit weight, and the results conclude that the dielectric constant, water contents and density of the ground proved to have a correlation among them, and the dielectric constant is expected to be a basic data on detection of levee leakage.

The Literature Study on Jung point venesection therapy (정혈(井穴) 자락요법(刺絡療法)에 관(關)한 문헌고찰(文獻考察))

  • Kim, Yoon-hee;Lee, Hyun;Lee, Byung-ryul
    • Journal of Haehwa Medicine
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    • v.10 no.1
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    • pp.237-245
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    • 2001
  • I have come to next conclusions in consequnce of documentary study about medical books of many generations regarding Jung point venesection therapy. 1. Jung point is significant as the beginning of pulse energy flow on meridian, the origin of all meridional pulse energy being located at extrimity terminal, confluence of three yin and three yang, and emergent treatment point. 2. Jung point venesection therapy was much used for the first-aid treatment for acute and thermic disease, and that is the combination of the meaning as of restoration from death and emergent treatment of Jung point and function of openning of orifice, leakage of fever, circulation of blood, remove of edema of venesection therapy. 3. It is very much used for emergency case, five sensory organ disease and CVA, heating shock and so on. Besides that digestive disease, cough, fever with cold, childhood disease, cardiac ache, thoracic disease, numbness of digitus terminal, mental disorder follow that in order. 4. Sosang, Jung point of Arm Greater Yin Lung meridian, is very much used for five sensory organ disease. Sosang is for orbital disease, sangyang for auditory disease, sosang for nasal disease, and sosnag for introitus-throat disease. 5. Ten Jung point is most used for first-aid diseases of CVA, heating shock. 6. Ten Jung point is most used for digestive disease of stomach ache, vomiting, diarrhea, intestinal convulsion. 7. Ten Jung point is most used for cold disease of cough, fever, malaria. 8. Ten Jung point, sosang, kwanchung are much used for childhood disease of acute convulsion and fever. 9. Among Jung point, sosang is most used, 34 times. Next there are Ten Jung point, kwanchung, sangyang, sotaek, jungchung, unbaek, taedon in order. In the order of frequency in use, arm channel is more used than leg channel.

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Improvement of Electromagnetic Shielding Structure for Reduction of the Leakage Magnetic Field in WPT System (WPT 시스템의 누설자계 감소를 위한 전자파 차폐구조 개선)

  • Kim, Jongchan;Lee, Seungwoo;Kang, Byeong-Nam;Hong, Ic-Pyo;Cho, In-Kui;Kim, Nam
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.28 no.1
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    • pp.61-68
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    • 2017
  • In this paper, we propose an improved magnetic field shielding structure to reducing the magnetic field generated in the wireless power transfer system operating at a low frequency band. The proposed structure consists of the magnetic material and the conductive material, magnetic field cancelling effect for power transfer is minimized while improving the leakage magnetic field cancelling effect by optimizing the various design parameters in the proposed structure. We analyzed and verified the efficiency of the wireless power transfer system and the reduction effect of the leakage magnetic field through computer simulation and measurement. Analysis results show that power transfer efficiency of the wireless power transfer system utilizing the proposed structure is 77 %, which is maintained at the conventional power transfer efficiency. In addition, compared with the structure maintaining high power transfer efficiency, leakage magnetic field strength is reduced to 29~37 % at the nearest point.

Analysis of a Novel Elevated Source Drain MOSFET with Reduced Gate-Induced Drain Leakage and High Driving Capability (Gate-Induced Drain Leakage를 줄인 새로운 구조의 고성능 Elevated Source Drain MOSFET에 관한 분석)

  • Kim, Gyeong-Hwan;Choe, Chang-Sun;Kim, Jeong-Tae;Choe, U-Yeong
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.38 no.6
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    • pp.390-397
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    • 2001
  • A novel self-aligned ESD (Elevated Source Drain) MOSFET structure which can effectively reduce the GIDL (Gate-Induced Drain Leakage) current is proposed and analyzed. The proposed ESD structure is characterized by sidewall spacer and recessed-channel depth which are determined by dry-etching process. Elevation of the Source/Drain extension region is realized so that the low-activation effect caused by low-energy ion implantation can be avoided. Unlike the conventional LDD structures, it is shown that the GIDL current of the ESD structure is suppressed without sacrificing the maximum driving capability. The main reason for the reduction of GIDL current Is the decreased electric field at the point of the maximum band-to-band tunneling as the peak electric field is shifted toward the drain side.

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Security Policy Proposals through PC Security Solution Log Analysis (Prevention Leakage of Personal Information) (PC보안솔루션 로그분석을 통한 보안정책 제안 (개인정보유출 방지))

  • Chae, Hyun Tak;Lee, Sang-Jin
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.24 no.5
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    • pp.961-968
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    • 2014
  • In order to prevent leakage of personal information by insiders a large number of companies install pc security solutions like DRM(Digital Right Management), DLP(Data Loss Prevention), Personal information filtering software steadily. However, despite these investments anomalies personal information occurred. To establish proper security policy before implementing pc security solutions, companies can prevent personal information leakage. Furthermore by analyzing the log from the solutions, companies verify the policies implemented effectively and modify security policies. In this paper, we define the required security solutions installed on PC to prevent disclosure of personal information in a variety of PC security solution, plan to integrate operations of the solutions in the blocking personal information leakage point of view and propose security policies through PC security solution log analysis.

Development on Early Warning System about Technology Leakage of Small and Medium Enterprises (중소기업 기술 유출에 대한 조기경보시스템 개발에 대한 연구)

  • Seo, Bong-Goon;Park, Do-Hyung
    • Journal of Intelligence and Information Systems
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    • v.23 no.1
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    • pp.143-159
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    • 2017
  • Due to the rapid development of IT in recent years, not only personal information but also the key technologies and information leakage that companies have are becoming important issues. For the enterprise, the core technology that the company possesses is a very important part for the survival of the enterprise and for the continuous competitive advantage. Recently, there have been many cases of technical infringement. Technology leaks not only cause tremendous financial losses such as falling stock prices for companies, but they also have a negative impact on corporate reputation and delays in corporate development. In the case of SMEs, where core technology is an important part of the enterprise, compared to large corporations, the preparation for technological leakage can be seen as an indispensable factor in the existence of the enterprise. As the necessity and importance of Information Security Management (ISM) is emerging, it is necessary to check and prepare for the threat of technology infringement early in the enterprise. Nevertheless, previous studies have shown that the majority of policy alternatives are represented by about 90%. As a research method, literature analysis accounted for 76% and empirical and statistical analysis accounted for a relatively low rate of 16%. For this reason, it is necessary to study the management model and prediction model to prevent leakage of technology to meet the characteristics of SMEs. In this study, before analyzing the empirical analysis, we divided the technical characteristics from the technology value perspective and the organizational factor from the technology control point based on many previous researches related to the factors affecting the technology leakage. A total of 12 related variables were selected for the two factors, and the analysis was performed with these variables. In this study, we use three - year data of "Small and Medium Enterprise Technical Statistics Survey" conducted by the Small and Medium Business Administration. Analysis data includes 30 industries based on KSIC-based 2-digit classification, and the number of companies affected by technology leakage is 415 over 3 years. Through this data, we conducted a randomized sampling in the same industry based on the KSIC in the same year, and compared with the companies (n = 415) and the unaffected firms (n = 415) 1:1 Corresponding samples were prepared and analyzed. In this research, we will conduct an empirical analysis to search for factors influencing technology leakage, and propose an early warning system through data mining. Specifically, in this study, based on the questionnaire survey of SMEs conducted by the Small and Medium Business Administration (SME), we classified the factors that affect the technology leakage of SMEs into two factors(Technology Characteristics, Organization Characteristics). And we propose a model that informs the possibility of technical infringement by using Support Vector Machine(SVM) which is one of the various techniques of data mining based on the proven factors through statistical analysis. Unlike previous studies, this study focused on the cases of various industries in many years, and it can be pointed out that the artificial intelligence model was developed through this study. In addition, since the factors are derived empirically according to the actual leakage of SME technology leakage, it will be possible to suggest to policy makers which companies should be managed from the viewpoint of technology protection. Finally, it is expected that the early warning model on the possibility of technology leakage proposed in this study will provide an opportunity to prevent technology Leakage from the viewpoint of enterprise and government in advance.

Numerical Study on Atmospheric Dispersion and Fire Possibility in Toluene Leakage (톨루엔 누출 시 대기확산 및 화재가능성에 관한 수치해석 연구)

  • Ko, Jae Sun;Kim, Joo-Seok
    • Fire Science and Engineering
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    • v.31 no.3
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    • pp.1-10
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    • 2017
  • This study examined the risk of accidents when handling hazardous materials in hazardous materials storage facilities without safety facilities. In the case of illegal dangerous cargo containers, the burning rate is very fast in the case of fire, which leads to explosions, that are damaging and difficult to control. In addition, accidents that occur in flammable liquid hazardous materials are caused mostly by accidents that occur in the space due to leakage. Therefore, the variables that affect these accidents were derived and the influence of these variables was investigated. Numerical and computational fluid dynamics programs were used to obtain the following final results. First, when a flammable liquid leaks into a specific space, it is influenced by temperature and relative humidity until a certain concentration (lower limit of combustion) is reached. In the case of temperature, it was found that the reaching time was shorter than the flash point In addition, the effect of variables on pool fire accidents of leakage tanks is somewhat different, but the variables that have the largest influence are the wind speed. Therefore, it is expected that the results of this study will be used as basic data for similar numerical analysis and it will provide useful numerical information about the accidental leakage of hazardous materials under various research conditions.

A Study on the Wedge shape Detector of Very High Resolution Positron Emission computer Tomography (초고해상도 양전자 방출 CT의 쐐기형 검출기에 관한 연구)

  • 이행세;이태원
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.22 no.2
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    • pp.44-54
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    • 1985
  • The high resolution of positron emission tomography, in particular, requires the use of detector crystals of narrow width but still with sufficiently high detection efficiency. If the crystal width is reduced to several millimeters, degradation of detection efficiency and leakage coefficient becomes significant, particularly in case of obliquely incident photons. Alleviation of such a problem can be made possible by modification of the detector shape from the conventional rectangular type to a wed농e type. The Proposed wedge shape makes the absorption length longer for obliquely incident photons, thus increasing the detection efficiency and suppressing leakage coefficient. For the BGO detectors of 4-8mm width, the computer simulation result of the system using wedge detectors reveals resolution improvement to the system using conventional detectors. For the system composed of 200 BGO detectors of 8mm width with 2 point sampling motion, the simulation resolution system using conventional detectors. For the very high resolution system of 3-7mm FWHM, the characteristics of the detector shape and size is studied by computer simulation.

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Estimation of the Relative Risk of the Elderly with Different Evacuation Velocity in a Toxic Gas Leakage Accident (독성물질 누출 시 대피 속도 차이에 따른 고령자의 상대적 위험도 산정)

  • Lee, H.T.;Kwak, J.;Park, J.;Ryu, J.;Lee, J.;Jung, Seungho
    • Journal of the Korean Society of Safety
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    • v.34 no.6
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    • pp.13-21
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    • 2019
  • Leakage accidents in businesses dealing with hazardous chemicals can have a great impact on the workers inside the workplace, as well as residents outside the workplace. In fact, there were cases where hazardous chemicals leaked from many businesses. As a result, the Chemicals Control Act(CCA) was enacted in 2015, the Ministry of Environment introduced an Off-site Risk Assessment(ORA). The purpose of the ORA is to secure safety from the installation of the design of the workplace facilities so that chemical accidents of hazardous chemical handling facilities do not cause human or physical damage outside the workplace. In general, the ORA qualitatively determines where a protected facility is within the scope of the accident scenario. However, elderly who belong to the sensitive group is more sensitive than the general group under the same chemical accident effect, and the extent of the damage is serious. According to data from the Korea National Statistic Office, the number of elderly people is expected to increase steadily. Therefore, a quantitative risk analysis considering the elderly is necessary as a result of a chemical accident. In this study, accident scenarios for 14 locations were set up to perform emergency evacuation due to toxic gas leakage of Cl2(Chlorine) and HF(Hydrogen Fluoride), and the effects of exposure were analyzed based on the evacuation velocity difference of age 20s and 60s. The ALOHA(Areal Locations of Hazardous Atmospheres) program was used to calculate the concentration for assessing the effects. The time of exposure to toxic gas was calculated based on the time it took for the evacuation to run from the start point to the desired point and a methodology was devised that could be applied to the risk calculation. As a result of the study, the relative risk of the elderly, the sensitive group, needs to be determined.