• Title/Summary/Keyword: Structure improvement

Search Result 4,073, Processing Time 0.032 seconds

Development of new agrochemicals by quantitative structure-activity relationship (QSAR) methodology. III. 3D QSAR methodologies and computer-assisted molecular design (CAMD) (정량적인 구조-활성상관 (QSAR) 기법에 의한 새로운 농약의 개발. III. 3D QSAR 기법들과 컴퓨터를 이용한 분자설계(CAMD))

  • Sung, Nack-Do
    • The Korean Journal of Pesticide Science
    • /
    • v.7 no.1
    • /
    • pp.1-11
    • /
    • 2003
  • Acoording to improvement of HTOS (high throughput organic synthesis) and HTS (high throughput screening) technique, the CoMFA (comparative molecular field analysis), CoMSIA (comparative molecular similarity indeces analysis) and molecular HQSAR (hologram quantitative structure-activity relationship) analysis techniques as methodology of computer assisted molecular design (CAMD) were introduced generally and summarized for some application cases.

Thermal Stability Improvement of Ni-Silicide using Ni-Co alloy for Nano-scale CMOSFET (나노급 CMOSFET을 위한 니켈-코발트 합금을 이용한 니켈-실리사이드의 열안정성 개선)

  • Park, Kee-Young;Jung, Soon-Yen;Han, In-Shik;Zhang, Ying-Ying;Zhong, Zhun;Li, Shi-Guang;Lee, Ga-Won;Wang, Jin-Suk;Lee, Hi-Deok
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.21 no.1
    • /
    • pp.18-22
    • /
    • 2008
  • In this paper, the Ni-Co alloy was used for thermal stability estimation comparison with Ni structure. The proposed Ni/Ni-Co structure exhibited wider range of rapid thermal process windows, lower sheet resistance in spite of high temperature annealing up to $700^{\circ}C$ for 30 min, more uniform interface via FE-SEM analysis, NiSi phase peak. Therefore, The proposed Ni/Ni-Co structure is highly promising for highly thermal immune Ni-silicide for nano-scale MOSFET technology.

A study on Determination of the Optimum Farm size based on Shadow Price of Rice (잠재가격에 의한 수도작 적정 영농규모 결정에 관한 연구)

  • Park, Jae Keun;Lim, Jae Hwan
    • Korean Journal of Agricultural Science
    • /
    • v.32 no.2
    • /
    • pp.127-150
    • /
    • 2005
  • Under the WTO system, the farm size expansion or the existing korean agricultural structure should be improved to cope with farm income decrease and to continue rice cultivation for food security in the future. This study is aimed at identifying optimum farm size under trade liberalization and import and export parity price system of inputs and outputs. The optimum farm size expressed the minimum point of long run average cost is determined as 15.1ha. The farm size to be equalized as urban laborer's income of 37,361 thousand won per year was revealed 30ha. Therefore the G't recommended farm size of 6ha should be changed to 30ha and the concerned policies for agricultural structure improvement also should be changed to more flexibilitiy.

  • PDF

A Study on Minimizing for Hydration Heat Cracks of a Subway Concrete Box Structure (지하철 콘크리트 BOX 구조물의 수화열에 의한 균열저감 대책 연구)

  • Kim, Eun-Kyum;Youn, Seok-Goo;Bae, Sang-Il;Jeong, Jae-Yong;Kim, Hyeon-Cheol;Heo, Jeong-Ok
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2006.05b
    • /
    • pp.425-428
    • /
    • 2006
  • The bigger of concrete strctures by a construct technique improvement, and the increase of the cement quantity which is caused by with use of the high-strength concrete for the load-carrying-capacity and a durability cause temperature cracks by a heat of hydration. The temperature crack due to the heat of hydration classified a nonstructural crack. but it has a bad effect on durability of concrete structures. especially, in case of a subway concrete box structure, when a water-proof facilities is beaked on an outer-wall, the water leakage occurs through a penetration crack generated from a wall of the concrete structure too. This paper, for the subway concrete box strucuture, the use of blended cement, the temperature of air and concrete, control joint, was considered and analysed by a three dimensional finite element method.

  • PDF

Analytical Technique on CFTA Girder Bridge Considering Construction Sequence (시공단계를 고려한 CFTA 거더교의 해석기법)

  • Park, Seung-Jae;Kim, Yong-Jae;Jeon, Jong-Su;Park, Myoung-Gyun;Park, Kyung-Hoon
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2009.05a
    • /
    • pp.167-168
    • /
    • 2009
  • The CFT structure is applied to newly developed CFTA girder because of improvement of ductility deformation, stiffness and internal force of structure owing to the interaction between steel tube and core concrete. CFTA girder is the structure which can reduce tensile stress due to external loads by using its arch shape and prestress force. This paper proposed constructional stage procedure and represented analytical technique considering constructional stage to investigate the safety against bridge collapse on construction and on operation.

  • PDF

Improvement of Concrete Durability under Deicier and Freez-Thaw Environment (제설제 및 동결융해 환경하에서 콘크리트의 내구성 증진 방안에 관한 연구)

  • Lee, Byung-Duck;Yun, Byung-Sung
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2005.11a
    • /
    • pp.523-526
    • /
    • 2005
  • In order to traffic safety during winter season, snowfall and cold area has been spread the deicing chemicals, and the spraying amount is increasing every year. Use of deicing chemicals has been and will continue to be a major part of highway snow and ice control methods. Chloride-containing chemicals such as calcium chloride or rock salt are main deicers for the road. Extensive use of chloride deicers is, however, the source of substantial cost penalties due to their corrosive action and acceleration to deterioration concrete structures. Deterioration due to de-icer salt occurs in practice in concrete pavement, dike, barrier and similar structure. This paper reports the results of effect of de-icer salt on durability of concrete structure in winter. To protect concrete structure from damage by de-icer salt in winter, the exposure test was performed using three methods such as increase in design strength upto 32MPa application of granulated blast furnace slag powder, and concrete sealer. Of these, the method of increase in design strength upto 32MPa showed better durability for deterioration by de-icer salt.

  • PDF

The study on the electrical and optical characteristics of a new structure for color AC plasma display (AC-PDP의 새로운 셀구조와 그 전기 광학적 특성에 관한 연구)

  • Park, Jae-Moon;Kim, Young-Kee;Lee, Jae-Young;Shin, Joong-Hong;Cho, Jung-Soo;Park, Chung-Hoo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2000.05b
    • /
    • pp.128-130
    • /
    • 2000
  • A new type ac plasma display panels(PDPs) cells are designed and tested electrically and optically. One cells have the structure of sin discharge path shape and small electrode area. The other cells have the non-symmetric structure with a same electrode area. They show a higher luminous efficienccy and a lower power consumption about 30% improvement than the conventional standard ac PDP cells.

  • PDF

Design Sensitivity Analysis of Elasto-perfectly-plastic Structure for Stiffened Shell Structure (탄성-완전-소성 보강쉘 구조물의 설계민감도해석)

  • Jung, Jae-Joon;Lee, Tae-Hee;Lim, Jang-Keun
    • Proceedings of the KSME Conference
    • /
    • 2001.11a
    • /
    • pp.746-752
    • /
    • 2001
  • Design sensitivity analysis for nonlinear structural problems has been emerged in the last decade as a glowing area of engineering research. As a result, theoretical formulations and computational algorithms have already developed for design sensitivity of nonlinear structural problems. There is not enough research for practical nonlinear problems using multi-element, due to difficulties of implementation into FEA. Therefore, nonlinear response analysis for stiffened shell which consists of Mindlin plate and Timoshenko beam, was considered. Specially, it presents the backward-Euler method which is adopted to describe an exact yield state in the stress computation procedure. Then, design sensitivity analysis of nonlinear structures, particularly elasto-perfectly-plastic structure, is developed using direct differentiation method. The accuracy of the developed sensitivity analysis was compared with the central finite difference method. Finally, on the basis of above results, design improvement for stiffened shell is suggested.

  • PDF

RBF Neural Networks-Based Adaptive Noise Filtering from the ECG Signal (방사기저함수 신경망을 기반한 ECG신호의 적응펄터링)

  • 이주원;이한욱;이종회;장두봉;김영일;이건기
    • Proceedings of the IEEK Conference
    • /
    • 1999.11a
    • /
    • pp.1159-1162
    • /
    • 1999
  • The ECG signal is very important information for diagnosis of patient and a cardiac disorder. It is hard to remove the noise because that is mixed with a lot of noise, and the error of the filtering will distort the ECG signal. The existing method for the filtering of the ECG signal has structure that has many steps for filtering, so that structure is complex and the processing speed is slow. For the improvement of that problem, we propose the method of filtering that has simple structure using the RBF neural networks and have good results.

  • PDF

An Analytic Model of Field Limiting Ring Structure (Field Limiting Ring 구조의 해석적 모델)

  • 라경만;정상구;최연익;김상배
    • Journal of the Korean Institute of Telematics and Electronics A
    • /
    • v.31A no.7
    • /
    • pp.95-101
    • /
    • 1994
  • A novel concept for the analysis of planar devices with a field limiting ring(FLR) is presented which allows analytic expressions in a normalized form for the potential distributions of FLR structure. Based on the method of image charges the main and ring junctions with identical cylindrical edges are kept to be two different equipotential surfaces. The potential relations between main and ring junction of the FLR structure are compared with 2-dimensional device simulation program. MEDICI. A good accordance is found. Comparisions with experimental data reported for the optimum ring spacing and the relative improvement of the breakdowm voltages in the FLR sturcture show the validity of the concept. The normalized expressions allow a universal application regardless to the junction depths and background doping levels.

  • PDF