• Title/Summary/Keyword: CEN

Search Result 136, Processing Time 0.028 seconds

A Study on the Evaluation of Activity factor of Fay ash (플라이애시의 활성지수 평가에 관한 연구)

  • Park, Sang-Joon;Won, Cheol;Yoo, Jae-Kang
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2004.05a
    • /
    • pp.572-575
    • /
    • 2004
  • A fundamental study was executed in order to evaluate quantitatively the effect on strength characteristic of concrete or mortar by fly ash. As a result, it was confirmed that the appropriate usage of fly ash is in existence comply with mix condition and characteristic of fly ash. And, we could evaluate the activity factor of fly ash. But, there are many problem in actual application because that the object of this study is only Method(2) out of the evaluation methods of activity factor proposed by CEN. Therefore, it is necessary to keep up an additional study.

  • PDF

Design of an Image Interpolator for Low Computation Complexity

  • Jun, Young-Hyun;Yun, Jong-Ho;Park, Jin-Sung;Choi, Myung-Ryul
    • Journal of Information Processing Systems
    • /
    • v.2 no.3 s.4
    • /
    • pp.153-158
    • /
    • 2006
  • In this paper, we propose an image interpolator for low computational complexity. The proposed image interpolator supports the image scaling using a modified cubic convolution interpolation between the input and output resolutions for a full screen display. In order to reduce the computational complexity, we use the difference in value of the adjacent pixels for selecting interpolation methods and linear function of the cubic convolution. The proposed image interpolator is compared with the conventional one for the computational complexity and image quality. The proposed image interpolator has been designed and verified by Verilog HDL(Hardware Description Language). It has been synthesized using the Xilinx VirtexE FPGA, and implemented using an FPGA-based prototype board.

Planar Error Sensitivity Analysis in a CNC Turning Cen (2차원 CNC 선반에서 평면오차 민감도 분석)

  • 여규환;이진현;양승한
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 1995.10a
    • /
    • pp.1017-1021
    • /
    • 1995
  • Geometric and thermal errors are responsible for major components of the errors of a computer numerically controlled turning center. The planar error of a CNC turning center are comprised of 11 geometric and thermal error components. The error synthesis model is formulated by homogeneous coordinate transformation method and expresses the effect of such error components on the planar error of a CNC turning center. In this paper, the sensitivity analysis of the model on the noises through sensing and the change of temperature is addressed. The sensitivity analysis show that the error systhesis model is robust on the noses and z planar error is much affected by the change of temperatures.

  • PDF

Eurocode 4: A modern code for the design of composite structures

  • Stark, Jan
    • Steel and Composite Structures
    • /
    • v.5 no.4
    • /
    • pp.327-343
    • /
    • 2005
  • The European Standards Organisation (CEN) has planned to develop a complete set of harmonized European building standards. The Eurocodes, being the design standards, form part of this total system of European standards, together with standards for fabrication and erection and product standards. After a period of experimental use of the ENV(European Pre Standard)-versions of the Eurocodes, these are now converted into official EN's (European Standards). Design of composite steel and concrete buildings and bridges is covered by Eurocode 4. An overview will be given of the historic development of Eurocode 4, the structure and contents of the EN version and the present status and planning for completion. The Eurocode treatment of some selected technical items will be presented in more detail.

A Comparative Study on the Floor Vibration Evaluation methods of Flat Plate Slab System (플랫슬래브 바닥구조시스템의 진동계산식의 비교)

  • Kang, Dae-Eon;Kim, Jong-Ho;Kim, Ji-Dong
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2008.11a
    • /
    • pp.153-156
    • /
    • 2008
  • The serviceability evaluation methods regarding floor vibration can be found in foreign building codes or design guides for vibration. AISC, AIJ, CEN, CSA and ISO are sucn examples. However, because the those guides are based on each country's experimental results, there will be different evaluation results for the same conditions. Meanwhile, in korea, we have little research results that suits for our condition, and we continue to use those foreing guides. In this paper, 20 flat plate slabs were carried out to investigate the accuracy of existing frequency formulas.

  • PDF

Optimization of ${\gamma}-Polyglutamic$ Acid Production by Bacillus subtilis ZJU-7 Using a Surface-response Methodology

  • Shi, Feng;Xu, Zhinan;Cen, Peilin
    • Biotechnology and Bioprocess Engineering:BBE
    • /
    • v.11 no.3
    • /
    • pp.251-257
    • /
    • 2006
  • The components of the media used to elicit the biosynthesis of $poly-{\gamma}-glutamic$ acid $({\gamma}-PGA)$ by Bacillus subtilis ZJU-7 were investigated, particularly the carbon and nitrogen sources Of the 7 carbon sources investigated, sucrose induced the highest rate of ${\gamma}-PGA$ productivity; among the nitrogen sources, tryptone had the best effect for ${\gamma}-PGA$ production. A $2^{6-2}$ fractional factorial design was used to screen factors that influence ${\gamma}-PGA$ production significantly, and a central composite design was finally adopted to formulate the optimal medium. ${\gamma}-PGA$ productivity improved approximately 2-fold when the optimal medium was used compared with the original nonoptimized medium, and volumetric productivity reached a maximum of 58.2 g/L after a 24-h cultivation period.

COUNTING THE CINTRALIZERS OF SOME FINITE GROUPS

  • Ashrafi, Ali Reza
    • Journal of applied mathematics & informatics
    • /
    • v.7 no.1
    • /
    • pp.115-124
    • /
    • 2000
  • For a finite group G, #Cent(G) denotes the number of cen-tralizers of its clements. A group G is called n-centralizer if #Cent( G) = n. and primitive n-centralizer if #Cent(G) = #Cent(${\frac}{G}{Z(G)$) = n. In this paper we compute the number of distinct centralizers of some finite groups and investigate the structure of finite groups with Qxactly SLX distinct centralizers. We prove that if G is a 6-centralizer group then ${\frac}{G}{Z(G)$${\cong}D_8$,$A_4$, $Z_2{\times}Z_2{\times}Z_2$ or $Z_2{\times}Z_2{\times}Z_2{\times}Z_2$.

HIGH-ORDER WEIGHTED DIFFERENCE SCHEMESTHE CONVECTION-DIFFUSION PROBLEMS

  • Choo, S.M.;Chung, S.K.;Kim, Y.H.
    • Communications of the Korean Mathematical Society
    • /
    • v.14 no.4
    • /
    • pp.815-832
    • /
    • 1999
  • High-order weighted difference schemes with uniform meshes are considered for the convection-diffusion problem depending on Reynolds numbers. For small Reynolds numbers, a weighed cen-tral difference scheme is suggested since there is no boundary layer. For large Reynolds numbers, we propose a modified up wind method with an artificial diffusion in order to overcome nonphysical oscilla-tion of central schemes and obtain good accuracy in the boundary later. Existence and corresponding error estimates of the solution for the difference scheme have been shown. Numerical experiments are provided to back up the analysis.

  • PDF

A Study on the Ritual Dress and Ideology in the Korean New Religions (한국신 신종교 의례복식과 사고에 관한연구)

  • 임상임
    • Journal of the Korean Society of Costume
    • /
    • v.27
    • /
    • pp.41-52
    • /
    • 1996
  • This thesis is a rearch on ritual dresses and ideology of new Korean religions primarily cen-tering on the way how religions ideology has been expressed into them. THe results are as follows" 1. The representative ideology in new Korean religions is the beginning of the world after the end religional union anthropocentrism ethno-centrism and social reform. 2 The creator of Mirukbulgyo hinm-self made the ritual dress for Mirukbulgyo Therefore his thought and the thought new religions are expressed variously on literatiure and ritual dress Ritual dress which has been wearing to all the believers show the thought of social reform also it is not connected with the social position and sex distinction. That ritual dresses are used the part of boue color appears the thought of beginning of the world after the end and ethnocentrism The organization of all the dresses contains the ideol-ogy of religional joined-one. Each dress embodies the ideology of religional union and anthropocentrism in its Inhwagwan, Chungbok contains the ideology of religional union which Taosim prefominanates and ethnocentrism P'oui contains the ideology of beginning of the world after the end and the ideology of social reform.form.

  • PDF

The Standard of Sump Design in Pump Station (펌프장내 흡수정 설계 기준)

  • Roh, H.W.;Oh, O.S.;Lee, Y.H.
    • 유체기계공업학회:학술대회논문집
    • /
    • 2005.12a
    • /
    • pp.589-592
    • /
    • 2005
  • In general, the function of intake structure, whether it be a open channel, a fully wetted tunnel, a sump or a tank, is to supply an evenly distributed flow to a pump station. An even distribution of flow, characterized by strong local flow, can result in formation of surface or submerged vortices, and with certain low values of submergence, may introduce air into pump, causing a reduction of capacity and efficiency, an increase in vibration and additional noise. Unfortunately in order to design the sump station, the reasonable code or the standards weren't presented yet in Korea. Thus, some researchers had often referred the HI code, JSME code or CEN code to design the sump station. This study aims to prescribe the standard of sump design which were matched well the Korean pump station. Thus, the HI code and TSJ code would be interpreted fully to Korean language, the part of interpreted clauses of the western codes would be selected to compose the standard.

  • PDF