• Title/Summary/Keyword: leakage problems

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An Experimental Study on the Outside Waterproofing Construction Method of Underground Structures Using the High-Adhesion and High-Elasticity of Unvulcanized Sheet (비가황 고점착.고탄성의 균질시트를 이용한 지하 외방수공법에 관한 실험적 연구)

  • Shao, Xu-Dong;Kim, Seon-Hwa;Kwon, Ki-Joo;Kwak, Kyu-Sung;Oh, Sang-Keun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2009.05b
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    • pp.225-229
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    • 2009
  • It has been found that existing detects at the junction between waterproofing layer as well as the material and the surfaces of the construction when waterproofing sheet is employed in the currently used unground structures waterproofing technology, causing a series of problems such as the high cost to the maintenance for leakage and the durability. The purpose of this study is about reducing the waterpoofing defects in underground structures. consequently, the homogeneous sheet which has some quality such as the unvulcanizate, high-adhesion and high-elastic was examined on physical properties. As a test result, it was confirmed to have satisfied performance about the ks. However, it must be continued to study through mock-up test for confirming of site application.

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Automatic Measuring Apparatus for Salt and Dust Contamination (염진해 오손도 자동측정장치)

  • 최남호;구경완;이명섭;한상옥;정재기;조성배
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.11a
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    • pp.187-190
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    • 1999
  • To reduce the maintenance expence, and the possibility of electric outage and accident, accurate measurement should be carried. But the classical method has some problems in the aspect of man power, reliability, and expence. In this paper, we propose a new type apparatus, which could detect the degree of contamination on insulators on outdoor insulation system, such as transmission and distribution line insulator and bushing. The new type apparatus consists of Pelltier module, electrode system, and measuring part. At first leakage current detecting method was considered, then with the fault(oxidation of electrode) of that method we should propose a another method. We carried various test to prove the possiblity and reliability of the propoused apparatus. And we get some useful result with laboratory test.

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A Study on the lighting Installation Regulations in Waterpark, Public Bath and Similar Places for the Prevention of Electrical Shock (감전사고 방지를 위한 물놀이.입욕시설의 조명설비 시설규정 연구)

  • Kim, Chong-Min;Kim, Han-Sang;Kim, Gi-Hyun;Hwang, Kwang-Su
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2005.11a
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    • pp.339-344
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    • 2005
  • A person's body resistance in the waterpark, public bath and similar places is lower than any other places due to effect of water. So low voltage may create a shock hazard for the human body in case of leakage or fault currents from lighting unit etc. We researched the related regulations these are internal standards, NEC, IEC and investigated the actual conditions for the prevention of electrical shock due to lighting units in the waterpark, public bath and similar places. So we could present actual facilities's problems and solutions

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Authentication Template Protection Using Function Encryption (함수암호를 이용한 인증정보 Template 보호 기술)

  • Park, Dong Hee;Park, Young-Ho
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.29 no.6
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    • pp.1319-1326
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    • 2019
  • Recently, biometrics and location information are being used for authentication in many devices. However, these information are stored as plaintext in safe device or, stored as ciphertext in authentication server it is used for authentication in plaintext by decrypting. Therefore, the leakage of authentication information as well as hacking can cause fatal privacy problems. In this paper, we propose a technique that can be authenticated without exposing authentication information to ciphertext using function encryption.

Design of a Inverter type high efficiency Neon Tansformer using MOSFET. (MOSFET를 응용한 인버터식 고효율 네온관용 트렌스퍼머의 설계)

  • Byun Jei-Young;Kim Sung-Won;Kim Yoon-Ho
    • Proceedings of the KIPE Conference
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    • 2001.07a
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    • pp.623-626
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    • 2001
  • The neon transformer consists of magnetic circuit and leakage transformer. Since the silicon steel plate is used build a core, the system is big and heavy. Thus it is difficult to install Neon Sign it is even very dangerous if the system experiences a damage when it is installed inside. To overcome these problems, power electronic circuits are applied. The Inverter type Neon transformer using MOSFET is designed and implemented. The experimental results are described.

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A Power Supply for Welding machine of Reducing Conduction Losses (도전손실을 저감한 용접기용 전원장치)

  • Ra, B.H.;Koo, H.H.;Joe, K.Y.;Suh, K.Y.;Lee, H.W.
    • Proceedings of the KIEE Conference
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    • 1998.11a
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    • pp.192-194
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    • 1998
  • This paper proposes a power supply for welding machine of reducing conduction Losses. To improve the conventional Phased-Shift FB DC-DC converter's problems that the copper loss in the high frequency transformer and conduction losses in the 1st terms bridge switch device because the leakage energy in the high frequency transformer and inducing of circulating current. This paper suggested a new topology of FB PWM DC-DC converter for welding machine to minimize a circulating current.

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Super Coupling Dual-gate Ion-Sensitive Field-Effect Transistors

  • Jang, Hyun-June;Cho, Won-Ju
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.239-239
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    • 2013
  • For more than four decades, ion-sensitive field-effect transistor (ISFET) sensors that respond to the change of surface potential on a membrane have been intensively investigated in the chemical, environmental, and biological spheres, because of their potential, in particular their compatibility with CMOS manufacturing technology. Here, we demonstrate a new type of ISFET with dual-gate (DG) structure fabricated on ultra-thin body (UTB), which highly boosts sensitivity, as well as enhancing chemical stability. The classic ion-sensitive field-effect transistor (ISFET) has been confronted with chronic problems; the Nernstian response, and detection limit with in the Debye length. The super-coupling effects imposed on the ultra thin film serve to not only maximize sensitivity of the DG ISFET, but also to strongly suppress its leakage currents, leading to a better chemical stability. This geometry will allow the ISFET based biosensor platform to continue enhancement into the next decade.

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A Study on Cloud-Based Secure File Management Security Solutions According yo Information Protection Needs (정보보호 필요에 따른 클라우드 기반의 안전한 파일관리 보안솔루션 연구)

  • Kim, Hee-Chul
    • The Journal of the Korea institute of electronic communication sciences
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    • v.14 no.1
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    • pp.243-250
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    • 2019
  • In this paper, we develop a Secure File Management Security(: SFMS) based on media in a cloud environment to encrypt and decrypt cloud data on a computer using a Bluetooth - based cryptographic module. The Bluetooth cipher module makes it easy to browse files stored in the cloud, but it is never possible to browse without a module. It is a solution that fundamentally blocks the problems such as hacking and leakage of personal data that have recently become an issue.

A Cache Privacy Protection Mechanism based on Dynamic Address Mapping in Named Data Networking

  • Zhu, Yi;Kang, Haohao;Huang, Ruhui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.12
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    • pp.6123-6138
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    • 2018
  • Named data networking (NDN) is a new network architecture designed for next generation Internet. Router-side content caching is one of the key features in NDN, which can reduce redundant transmission, accelerate content distribution and alleviate congestion. However, several security problems are introduced as well. One important security risk is cache privacy leakage. By measuring the content retrieve time, adversary can infer its neighbor users' hobby for privacy content. Focusing on this problem, we propose a cache privacy protection mechanism (named as CPPM-DAM) to identify legitimate user and adversary using Bloom filter. An optimization for storage cost is further provided to make this mechanism more practical. The simulation results of ndnSIM show that CPPM-DAM can effectively protect cache privacy.

Balance Winding Scheme to Reduce Common-Mode Noise in Flyback Transformers

  • Fu, Kaining;Chen, Wei
    • Journal of Power Electronics
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    • v.19 no.1
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    • pp.296-306
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    • 2019
  • The flyback topology is being widely used in power adapters. The coupling capacitance between primary and secondary windings of a flyback transformer is the main path for common-mode (CM) noise conduction. A Y-cap is usually used to effectively suppress EMI noise. However, this results in problems in space, cost, and the danger of safety leakage current. In this paper, the CM noise behaviors due to the electric field coupling of the transformer windings in a flyback adapter with synchronous rectification are analyzed. Then a scheme with balance winding is proposed to reduce the CM noise with a transformer winding design that eliminates the Y-cap. The planar transformer has advantages in terms of its low profile, good heat dissipation and good stray parameter consistency. Based on the proposed scheme, with the help of a full-wave simulation tool, the key parameter influences of the transformer PCB winding design on CM noise are further analyzed. Finally, a PCB transformer for an 18W adapter is designed and tested to verify the effectiveness of the balance winding scheme.