• 제목/요약/키워드: EEC

검색결과 125건 처리시간 0.024초

A STUDY ON EROSION (CAUSES AND REMEDIES) BASED ON HYDROLOGICAL DATA

  • K.M. Ibe, Sr;H. Krynen
    • Water Engineering Research
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    • 제2권4호
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    • pp.269-276
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    • 2001
  • The project concentrates on an hydrological analysis. The analysis consists of rainfall, infiltration, Determination of runoff and sediment yield. The risque of erosion and the control measures are related to the slopes and land use. Therefore the first approach to erosion must be correct land use based on land classification. Basically there are two types of mechanical protection works; Drainage and Storage. Realization of a drainage system will be very costly and therefore temporary storage is preferred. For farmland in flat areas hardly any measures are needed. For farmland on slopes temporary storage can be effected by applying tillage with ridges within contour bunds. Along roads infiltration pits should be constructed and in areas with houses, the solution to avoid runoff will be water harvesting.

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CE Marking과 EN 규격동향

  • 이상규
    • The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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    • 제7권1호
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    • pp.22-31
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    • 1996
  • 1989년 5월 3일 발표된 EC(현 EU) Directive 89 / 336 / EEC(전자파 양립성 지령)에 의해, 1996년 1월 1일부터 EU 지역에서 생산 또는 EU 역내에 수입되는 모든 전기전자제품에 대해 CE Mark 가없이는 유통, 판매, 사용이 금지되기 시작했다. 이 지령은 EMC에 관한 각종 제품의 보호요건을 정의하고 있으며, 타제품 및 부문에 대해서도 EU 위 원회에서 제정한 각종 안전규정(Directives; 지령)에 적합할 경우, CE Mark를 부착하고, 이는 구주 역 내 국가간에 규제를 통일하고 안전성이 확보된 제품의 자유로운 유통(Free Movement of Goods)과 판매를 목적으로 한다. 이에 따라, EU위원회에서는 EMC를 비롯한 안전, 기계, 완구 등 여러 분야에 대해 각국의 규제를 조 정하고 일체화하여 현재까지 약 20종류의 EC지령을 발표하였다.

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A New Technology for Strengthening Surface of Forging Die

  • Xin Lu;Zhongde Liu
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 한국소성가공학회 2003년도 The 8th Asian Symposium on Precision Forging ASPF
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    • pp.189-192
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    • 2003
  • The Electro-thermal Explosion Coating (EEC) technique is a new surface treatment technology emerged in recent years. It uses an electrical discharge (with very high voltage from 5 to 30 kV or more) to produce a pulse current with large density inside the material to be deposited, the metal wire undergo the heating, melting, vaporization, ionization and explosion processes in a very short time (from tens ns to several hundreds ${\mu}s$), and the melted droplets shoot at the substrate with a very high velocity (3000 - 4500 m/s), so that the coating materials can be deposited on the surface of the substrate. Coatings with nano-size grains or ultra- fine grains can be formed because of rapid solidification (cooling rate up to $10^6-10^9\;k/s$). Surface of the substrate (about $1-5{\mu}m$ in depth) can be melted rapidly and coatings with very high bonding strength can be obtained.

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Study on EEC and SSC of the Electric Resistance Welded Linepipe Steel

  • Kim, Wan Keun;Koh, Seong Ung;Yang, Boo Young;Kim, Kyoo Young
    • Corrosion Science and Technology
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    • 제6권3호
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    • pp.96-102
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    • 2007
  • The resistance of the linepipe steel to hydrogen-induced cracking (HIC) and sulfide stress cracking (SSC) is very important for steel to be used in sour oil/gas environments. Welding of steels is necessary to the construction of pipe-line transporting oil/gas. In this study, HIC and SSC resistance of an electric resistance welded (ERW) steel plate which belongs to API X70 grade was evaluated by using NACE TM0284-96A and NACE TM0177-96A methods. HIC and SSC fracturing behavior was investigated by observing fractured surfaces using optical microscopy (OM) and scanning electron microscopy (SEM). It was discussed in terms of metallurgical parameters such as the distribution of primary microstructure, second phases and inclusions. Results showed that the weld joint of ERW steel is more sensitive than base metal to HIC and SSC. This is due to difference in the contribution of metallurgical parameters to HIC and SSC nucleation and propagation.

Mechanism and Characteristics of Nano-dispersed Powder by Pulsed Discharge Method

  • Kwon, Young-Soon;Ilyin, Alexander P.
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 한국분말야금학회 2003년도 international symposium on advanced powder metallurgy
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    • pp.27-32
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    • 2003
  • The phenomenon of electrical explosion of conductors is considered in the context of the changes in the energy and structural states of the metal at the stages of energy delivery and relaxation of the primary products of EEC. It is shown that these changes are related to the forced interaction of an intense energy flux with matter and to the subsequent spontaneous relaxation processes. The characteristics of nano-sized metal powders are also discussed.

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승용차의 시계 요소 조사 및 개선 방향

  • 정일석;이정근;정의승;윤명환;최재호;강동석
    • Proceedings of the ESK Conference
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    • 대한인간공학회 1997년도 추계학술대회논문집
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    • pp.114-119
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    • 1997
  • 자동차 내장 설계의 주요 검토 사항으로 거주성, 조작성, 시인/시계성, 승강성, 적재성, 안전성 등 을 들 수 있다. 특히, 승용차의 주행 시 운전자는 주위 환경에서 일어나는 상황의 대부분을 눈을 통해 인식하게 되므로, 주행 중 운전자에게 충분한 시계를 확보해 주는 것이 자동차의 설계에서 중요한 요인 이 된다. 본 연구에서는 시계성을 중심으로 미국의 FMVSS(Federal Motor Vehicle Sfety Standard), 유럽의 EEC(European Economy Community), 한국공업규격 등에서 규정하고있는 시계 요소들을 조사 비교하고, 시계 성 평가의 기준으로 활용한다. 시계성을 평가하기 위해 전방가시거리, 전방수평시계, Inside Rear View Mirror와 Outside Rear View Mirror를 통해 볼 수 있는 Viewing angle, Inside Rear View Mirror와 95%ile Eyellipse와 높이 등의 요소를 측정하였다. 측정 결과는 승용차의 운전 공간 내의 0ptimal Eye Point를 결 정하는 데 이용되며, 시인/시계성을 개선하는 Seating Packaging Procedure 개발의 기초 자료로 활용될 수 있을 것이다.

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A Study on Structure and Vibration Analysis of an Air Suspension Seat (에어 서스펜션 시트의 구조 및 진동해석에 관한 연구)

  • Ha, Jung-Soo;Lee, Gun-Myung
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • 제16권6호
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    • pp.47-54
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    • 2017
  • This study analyzed air suspension seat frame structure and vibration for 50 - 180 kg mass driver to obtain optimum seat design parameter values for the equivalent spring constant and damping coefficient. Various air suspension seat frames were designed following WTS-003 and KS B 6839 standards, and then evaluated using finite elements analysis. Resonance and vibration tests were performed according to the 78/764/EEC standard.

Design of an Area-efficient DCME Algorithm for High-speed Reed-Solomon Decoder (고속 Reed-Solomon 복호기를 위한 면적 효율적인 DCME 알고리즘 설계)

  • Kang, Sung Jin
    • Journal of the Semiconductor & Display Technology
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    • 제13권4호
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    • pp.7-13
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    • 2014
  • In this paper, an area-efficient degree-computationless modified Euclidean (DCME) algorithm is presented and implemented for high-speed Reed-Solomon (RS) decoder. The DCME algorithm can be used to solve the key equation in Reed-Solomon decoder to get the error location polynomial and the error value polynomial. A pipelined recursive structure is adopted for reducing the area of key equation solver (KES) block with sacrifice of an amount of decoding latency. For comparisons, KES block for RS(255,239,8) decoder with the proposed architecture is implemented using Verilog HDL and synthesized using Synopsys design tool and 65nm CMOS technology. The synthesis results show that the proposed architecture can be implemented with less gate counts than other existing DCME architectures.

A Review of Fixed-Complexity Vector Perturbation for MU-MIMO

  • Mohaisen, Manar
    • Journal of Information Processing Systems
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    • 제11권3호
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    • pp.354-369
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    • 2015
  • Recently, there has been an increasing demand of high data rates services, where several multiuser multiple-input multiple-output (MU-MIMO) techniques were introduced to meet these demands. Among these techniques, vector perturbation combined with linear precoding techniques, such as zero-forcing and minimum mean-square error, have been proven to be efficient in reducing the transmit power and hence, perform close to the optimum algorithm. In this paper, we review several fixed-complexity vector perturbation techniques and investigate their performance under both perfect and imperfect channel knowledge at the transmitter. Also, we investigate the combination of block diagonalization with vector perturbation outline its merits.