• 제목/요약/키워드: simplification

검색결과 1,069건 처리시간 0.031초

Simplification of the Flexural Capacity of SFR-UHPCC Rectangular Beam

  • 오향국;한상묵;김성욱;강수태
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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    • pp.526-529
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    • 2006
  • In this paper, flexure behavior of steel fiber reinforcement ultra high performance cementations composites (SFR-UHPCC) has been analyzed by equivalent stress block. Pulling-out tensile force of steel fiber with concrete matrix was induced. An appropriate flexure evaluation formula, i.e. semi-analytical formula, was established based on rectangular cross section beam for comparing with shear capacity and ultimate load of SFR-UHPCC beam. Finally, the semi-analytical formula has been simplified for the convenience of design work. Experimental results and theoretical shear strength are shown to compare with the formula proposed by this paper. The theory formula has a good prediction of failure type of SFR-UHPCC.

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Effects of Matrix Ductility on the Shear Performance of Precast Reinforced HPFRCC Coupling Beams

  • Yun Hyun-Do;Kim Sun-Woo;Jeon Esther;Park Wan Shin
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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    • pp.53-56
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    • 2005
  • This paper investigates the effect of ductile deformation behavior of high performance hybrid fiber-reinforced cement composites (HPHFRCCs) on the shear behavior of coupling beams to lateral load reversals. The matrix ductility and the reinforcement layout were the main variables of the tests. Three short coupling beams with two different reinforcement arrangements and matrixes were tested. They were subjected to cyclic loading by a suitable experimental setup. All specimens were characterized by a shear span-depth ratio of 1.0. The reinforcement layouts consisted of a classical scheme and diagonal scheme without confining ties. The effects of matrix ductility on deflections, strains, crack widths, crack patterns, failure modes, and ultimate shear load of coupling beams have been examined. The combination of a ductile cementitious matrix and steel reinforcement is found to result in improved energy dissipation capacity, simplification of reinforcement details, and damage-tolerant inelastic deformation behavior. Test results showed that the HPFRCC coupling beams behaved better than normal reinforced concrete control beams. These results were produced by HPHFRCC's tensile deformation capacity, damage tolerance and tensile strength.

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튜닝 가능한 자원선택 방법론 (Methodologies to Selecting Tunable Resources)

  • 김혜숙;오정석
    • Journal of Information Technology Applications and Management
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    • 제15권1호
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    • pp.271-282
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    • 2008
  • Database administrators are demanded to acquire much knowledges and take great efforts for keeping consistent performance in system. Various principles, methods, and tools have been proposed in many studies and commercial products in order to alleviate such burdens on database administrators, and it has resulted to the automation of DBMS which reduces the intervention of database administrator. This paper suggests a resource selection method that estimates the status of the database system based on the workload characteristics and that recommends tuneable resources. Our method tries to simplify selection information on DBMS status using data-mining techniques, enhance the accuracy of the selection model, and recommend tuneable resource. For evaluating the performance of our method, instances are collected in TPC-C and TPC-W workloads, and accuracy are calculated using 10 cross validation method, comparisons are made between our scheme and the method which uses only the classification procedure without any simplification of informations. It is shown that our method has over 90% accuracy and can perform tuneable resource selection.

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돌출된 특징을 위한 기하 모델 단순화 방법 (Geometric Model Decimation Method for Salient Features)

  • 김수균;안성옥
    • 컴퓨터교육학회논문지
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    • 제11권4호
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    • pp.85-93
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    • 2008
  • 본 논문은 3차원 기하 모델에서 돌출된 특징 영역을 유지하며 단순화하기 위한 방법에 관한 것으로서 3차원 레인지 스캐닝 시스템으로 부터 삼각형 기하 데이터를 입력받아 기하 데이터의 각 점들에 대해 근사화 표면을 생성하고, 생성된 표면에서의 점들에 대한 곡률과 곡률 미분 값을 측정한 후, 기하 데이터의 에지에 대해 제로-클로싱을 측정하여 특정점을 찾아낸다. 특정점을 주 곡률 방향으로 연결하여 특정 선을 생성하고, 거리기반오차에 특정에지오차를 조합한 FQEM(Feature Quadric Error Metric)을 이용하여 단순화를 수행하게 된다. 본 논문에서는 제안방법의 우수성을 기존 방법과의 실험결과의 비교를 통하여 보여 준다.

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도심지 터널굴착에 따른 인접 구조물과 지반거동의 상호영향에 대한 매개변수 연구 (A Parametric Study on the Interaction between Ground Movements and Adjacent Structures in Urban Tunnelling)

  • 강봉재;황의석;이봉렬;김학문
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2000년도 가을 학술발표회 논문집
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    • pp.485-492
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    • 2000
  • Current design practice for the prediction of tunnelling-induced ground movements depends on empirical methods, which are based on many assumptions and simplification of the modeling. Some discrepancies between the predictions and the measurements of ground movements regarding adjacent structures are inevitable. In order to investigate tunnel-induced ground movements affect on the settlement of existing structures as well as existing structures affect tunnel-induced ground movement, 2-D elasto-plastic finite element analysis are performed. The following influencing factors such as load of the structures, the width of structures, its bending and axial stiffness, its position relative to the tunnel are considered in the numerical analysis.

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외란 오브저버에의한 작업좌표공간에서의 다이렉트 드라이브 로보트의 위치와 힘의 하이브리드 제어 (Hybrid Position/Force Control of Direct Drive Robots by Disturbance Observer in Task Coordinate Space.)

  • 신정호;코마다 사토시;이시다 무네아키;호리 타카마사
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1992년도 하계학술대회 논문집 A
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    • pp.411-413
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    • 1992
  • This paper proposes a simple and high performance hybrid position/force control of robots based on disturbance compensation by using the disturbance observer in task coordinate space. The disturbance observer linealizes system of robot manipulators in task coordinate space and realizes acceleration control. To realize the strict acceleration control, the disturbance observer whose input is a position signal by simple computation, works as if it were a disturbance detector. The inverse kinematics can be simplified, because the disturbance observer in task coordinate space compensates not only the disturbance but also the error due to the simplification of the inverse kinematics. The new strategy is applied to a three-degrees-of freedom direct drive robot. The robust and simple hybrid position/force control is realized experimentally.

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Open Trade Technical Model using ebXML for FTA with China and Korea

  • Jung, Yong Gyu;Kang, Min Soo;Jung, Ga-Woon;Cha, Kwang Seung;Chong, Agatha
    • International Journal of Advanced Culture Technology
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    • 제2권1호
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    • pp.25-29
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    • 2014
  • China and South Korea have effectively reached a free trade agreement. The deal now faces legal and parliament reviews in the two countries. We need to discuss the recommendations on XML conversion with UN / CEFACT electronic documents. To solve this problem of interworking between these standards, Two kinds of translation rules is proposed for exchanging to UN / CEFACT Tag smoothly. For development and distribution of electronic documents to be conformed to international standards, it is enough to have the role of international activities continue to supply part of the domestic industry and the trends in participation and international standard. Our principal focus is on facilitating national and international transactions, through the simplification and harmonization of processes, procedures and information flows, and so contributing to the growth of global commerce. The agreement with South Korea will be China's ninth bilateral FTA.

쉬프트레지스터를 사용한 순서논리회로의 간단화에 관하여 (On the Logical Simplification of Sequential Machines using Shift-Registers)

  • 이근영
    • 대한전자공학회논문지
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    • 제15권4호
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    • pp.7-13
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    • 1978
  • 쉬프트레지스터 (SR) 모듈을 기억소자로서 사용하여 순서회로를 실현하는 방법을 논하였다. 종래의 방법은 특수한 조건하에서 SR를 선택하는 것으로서 그것을 구동하는 조합논리회로의 복잡도는 고려되지 않았다. 본 논문은 한 정수치함수를 사용하여 단수가 최소인 SR를 선택하였고 각 SR를 구동하는 조합논리회로의 입력선수를 비교하여 논리회로의 복잡도가 낮은 최적 상태할당을 구하였다.

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The Influence of the Aspect Ratio on the Composite Material Bridge Deck Structures

  • Han, Bong-Koo
    • Composites Research
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    • 제27권1호
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    • pp.1-6
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    • 2014
  • Theories for composite material structures are too difficult for such design engineers for construction and some simple but accurate enough methods are necessary. The author has reported that some laminate orientations have decreasing values of $D_{16}$, $B_{16}$, $D_{26}$ and $B_{26}$ stiffnesses as the ply number increases. For such plates, the fiber orientations given above behave as specially orthotropic plates and simple formulas developed by the author. Most of the bridge deck structures on girders have large aspect ratios. For such cases further simplification is possible by neglecting the effect of the longitudinal moment terms $M_x$ on the relevant partial differential equations of equilibrium. In this paper, the result of the study on the subject problem is presented.

경계 복셀 모델을 이용한 임의 형상의 비조직화된 점군으로부터의 3 차원 완전 형상 복원 (Complete 3D Surface Reconstruction from an Unstructured Point Cloud of Arbitrary Shape by Using a Bounding Voxel Model)

  • 이일섭;김석일
    • 대한기계학회논문집A
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    • 제30권8호
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    • pp.906-915
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    • 2006
  • This study concerns an advanced 3D surface reconstruction method that the vertices of surface model can be completely matched to the unstructured point cloud measured from arbitrary complex shapes. The concept of bounding voxel model is introduced to generate the mesh model well-representing the geometrical and topological characteristics of point cloud. In the reconstruction processes, the application of various methodologies such as shrink-wrapping, mesh simplification, local subdivision surface fitting, insertion of is isolated points, mesh optimization and so on, are required. Especially, the effectiveness, rapidity and reliability of the proposed surface reconstruction method are demonstrated by the simulation results for the geometrically and topologically complex shapes like dragon and human mouth.