• Title/Summary/Keyword: protection technique

Search Result 899, Processing Time 0.025 seconds

NAC Measurement Technique on High Parallelism Probe Card with Protection Resistors

  • Kim, Gyu-Yeol;Nah, Wansoo
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • v.16 no.5
    • /
    • pp.641-649
    • /
    • 2016
  • In this paper, a novel time-domain measurement technique on a high parallelism probe card with protection resistors installed is proposed. The measured signal amplitude decreases when the measurement is performed by Needle Auto Calibration (NAC) probing on a high parallelism probe card with installed resistors. Therefore, the original signals must be carefully reconstructed, and the compensation coefficient, which is related to the number of channel branches and the value of protection resistors, must be introduced. The accuracy of the reconstructed signals is analyzed based on the varying number of channel branches and various protection resistances. The results demonstrate that the proposed technique is appropriate for evaluating the overall signal performance of probe cards with Automatic Test Equipment (ATE), which enhances the efficiency of probe card performance test dramatically.

A Study on the Development of Optimization Procedure for Radiological Protection (방사선 방어의 최적화 절차론 개발에 관한 연구)

  • Song, Jong-Soon
    • Journal of Radiation Protection and Research
    • /
    • v.19 no.1
    • /
    • pp.1-11
    • /
    • 1994
  • Considering the variety of application and other factors in performing the optimization of radiological protection, it is necessary to use well-structured optimization procedure. In this study, an optimization procedure for design stage of nuclear power plant was proposed, and applied in the selection of alternatives for reducing occupational radiation exposure. As an aiding technique for decision-making, multi-criteria technique was used. As a result, priorities of alternatives are determined, and a problem of applying this result to real situation is reviewed. The developed procedure for optimization can be extended to other areas such as radioactive waste management, medical use of radiation, etc.

  • PDF

A Safety Assessment Methodology for a Digital Reactor Protection System

  • Lee Dong-Young;Choi Jong-Gyun;Lyou Joon
    • International Journal of Control, Automation, and Systems
    • /
    • v.4 no.1
    • /
    • pp.105-112
    • /
    • 2006
  • The main function of a reactor protection system is to maintain the reactor core integrity and the reactor coolant system pressure boundary. Generally, the reactor protection system adopts the 2-out-of-m redundant architecture to assure a reliable operation. This paper describes the safety assessment of a digital reactor protection system using the fault tree analysis technique. The fault tree technique can be expressed in terms of combinations of the basic event failures such as the random hardware failures, common cause failures, operator errors, and the fault tolerance mechanisms implemented in the reactor protection system. In this paper, a prediction method of the hardware failure rate is suggested for a digital reactor protection system, and applied to the reactor protection system being developed in Korea to identify design weak points from a safety point of view.

Experimental technique for efficiency transfer along different geometries and volumes

  • Haddad, Kh;AL-Homyed, A.
    • Nuclear Engineering and Technology
    • /
    • v.53 no.2
    • /
    • pp.695-698
    • /
    • 2021
  • Efficiency calibration is a fundamental procedure in gamma spectrometric measurement. Experimental technique for efficiency calibration transfer in gamma spectrometer along different geometries and volumes has been developed and validated in this work. The developed technique offers simple and easy procedures to overcome several problems encountered in efficiency calibration of gamma spectrometer such as rate-related correction and different sample volumes. The validation shows that application of the developed technique has a precision of 95%.

UEP Precoder Selection Technique for ML Detected SM MIMO Systems (ML검출 기반 공간다중화 MIMO 시스템의 UEP 프리코더 선정기술)

  • Park, Jaeyoung;Kim, Jaekwon
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.42 no.4
    • /
    • pp.747-749
    • /
    • 2017
  • In this paper, we propose a novel precoder selection technique for maximum-likelihood (ML) detected spatially multiplexed multiple-input multiple-output (MIMO) systems. Previous precoder selection techniques were designed without considering UEP, however the proposed technique is designed considering multi-antenna unequal error protection (UEP). Simulations demonstrate the improved multi-antenna UEP performance by the proposed technique.

A Design of DDPT(Dynamic Data Protection Technique) using k-anonymity and ℓ-diversity (k-anonymity와 ℓ-diversity를 이용한 동적 데이터 보호 기법 설계)

  • Jeong, Eun-Hee;Lee, Byung-Kwan
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
    • /
    • v.4 no.3
    • /
    • pp.217-224
    • /
    • 2011
  • This paper proposes DDPT(Dynamic Data Protection Technique) which solves the problem of private information exposure occurring in a dynamic database environment. The DDPT in this paper generates the MAG(Multi-Attribute Generalization) rules using multi-attributes generalization algorithm, and the EC(equivalence class) satisfying the k-anonymity according to the MAG rules. Whenever data is changed, it reconstructs the EC according to the MAC rules, and protects the identification exposure which is caused by the EC change. Also, it measures the information loss rates of the EC which satisfies the ${\ell}$-diversity. It keeps data accuracy by selecting the EC which is less than critical value and enhances private information protection.

Performance Comparison of Wavelet Transform Based Watermarking and DCT Transform Based Watermarking (Wavelet 변환과 DCT 변환을 이용한 워터마킹에 관한 연구)

  • 장용원;한승수;김인택
    • Proceedings of the IEEK Conference
    • /
    • 2000.11c
    • /
    • pp.85-88
    • /
    • 2000
  • With the rapid growth of network distributions of digitized media(audio, image, and video), there is an urgent need for copyright protection. For now watermarking is a well-known technique for copyright protection of digital data. To embed a digital watermark to the image, discrete cosine transform(DCT) and wavelet transform are commonly used. In this paper, the performance of the DCT based watermarking technique and wavelet based watermarking technique were compared and the influences of the parameter a that decides the strength of the watermarking data were considered.

  • PDF

An Unavailability Evaluation for a Digital Reactor Protection System (디지털 원자로보호계통 불가용도 평가)

  • Lee, Dong-Yeong;Choe, Jong-Gyun;Kim, Ji-Yeong;Yu, Jun
    • Proceedings of the KIEE Conference
    • /
    • 2005.05a
    • /
    • pp.81-83
    • /
    • 2005
  • The Reactor Protection System (RPS) is a very important system in a nuclear power plant because the system shuts down the reactor to maintain the reactor core integrity and the reactor coolant system pressure boundary if the plant conditions approach the specified safety limits. This paper describes the unavailability assessment of a digital reactor protection system using the fault tree analysis technique. The fault tree technique can be expressed in terms of combinations of the basic event failures. In this paper, a prediction method of the hardware failure rate is suggested for a digital reactor protection system. and applied to the reactor protection system being developed in Korea.

  • PDF

Design of a Flight Envelope Protection System Using a Dynamic Trim Algorithm

  • Shin, Ho-Hyun;Lee, Sang-Hyun;Kim, You-Dan;Kim, Eung-Tae;Sung, Ki-Jung
    • International Journal of Aeronautical and Space Sciences
    • /
    • v.12 no.3
    • /
    • pp.241-251
    • /
    • 2011
  • Most large commercial aircrafts and high performance military aircrafts use fly-by-wire (FBW) or fly-by-light systems to improve their controllability, comfort, and safety. A flight envelope protection technique is used with flight control systems utilizing the FBW technique. Such flight envelope protection systems prevent these aircraft from exceeding the structural/aerodynamic limits and control their surface limits. This is accomplished by predicting the values of the future state variables and adaptively compensating the control action. In this study, the conventional dynamic trim algorithm of the flight envelope protection is modified to increase the method accuracy and to handle cases with multiple variables. Numerical simulation is also performed to verify the performance of the proposed method.

An Improvement of Distance Relay Technique Reliability using Elman Network (Elman Network를 이용한 거리계전기법의 신뢰성 향상)

  • Jung, H.S.;Lee, J.J.;Shin, M.C.;Lee, B.K.;Park, C.W.;Jang, S.I.
    • Proceedings of the KIEE Conference
    • /
    • 2000.07a
    • /
    • pp.212-214
    • /
    • 2000
  • The distance relay technique used for transmission line protection operates overreach and underreach to the self protection region because the power system becomes complex and fault conditions are different. To solve these problems, this paper describes new technique to set the reliable self protection lesion. The trip region of the quadrilateral distance relay is set by training of multi layer recurrent elman network. The proposed network is able to reach the trip zone for the fault impedance, fault initial angle and source impedance variance correctly.

  • PDF