• Title/Summary/Keyword: Local Minimum

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The Characteristics of Various Deviation by Block Adjustment According to GCP Arrangement (GCP 배치에 따른 Block 조정의 오차 전파 특성)

  • Kang, Joon-Mook;Um, Dae-Yong;Kang, Young-Mi;Jeon, Kyong-Min
    • Journal of Korean Society for Geospatial Information Science
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    • v.10 no.3 s.21
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    • pp.29-40
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    • 2002
  • In photogrammetry, the accuracy is analyzed by using the coordinate of the targeted position determined by the geometric principle, thus, the reliability depends on the accuracy of the coordinate of the targeted position. Thereby, geographic surveying is essential to perform such tasks, and it requires approximately $30{\sim}50%$ of total cost and times to produce a finalized map. The main purpose of this study is to determine the configuration of the disposition of minimum datum points and their configuration, which were determined by surveying values available through using the structure of block model based on the aerotriangulation. ortho projection image was produce and digital topographic map was achieved by the optima model(CASE7). We also performed comparative analysis about the result of local datum point and the accuracy of overlapping based on the surveying results. Consequently, it is possible to analyze the unknown position accurately with the optimal model., CASE 7, which is the minimum datum points configuration required to block adjustment. Furthermore, this optimal model, which provides the minimum datum points, results costs and time saving effects compared to the previous methodology.

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A Study on the independence of local government in Korea (지방의회 인사권 독립에 관한 연구: 헌재 지방자치법 제91조 제2항 위헌소원 결정을 중심으로)

  • Lee, Sanggab
    • Korea and Global Affairs
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    • v.2 no.2
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    • pp.5-40
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    • 2018
  • The history of decentralization and autonomy is the result of the struggle for democracy against the authoritarian central government. Before the imminent law amendment, there are many tasks for decentralization and citizen autonomy. Therefore, decentralization and autonomy are not given on their own but they must be taken from authoritarian and centralist power group which possesses exclusive interests. The decentralization and autonomy now enters into the stage of development. In 1960, the April 19 Revolution opened the era of democratic local autonomy and it was abolished by the military coup of May 16, Now, the era of the reform of the decentralization are coming. Decentralization and autonomy will evolve from the stage of quantitative expansion to the stage of qualitative leap. This paper proposes that the revision of decentralization be the strategic maximum, and that the independence of the local government personnel rights be the tactical minimum. This paper insists that the independence of personnel right in the local government can be a link with law amendment for decentralization. Local autonomy and decentralization are the main subjects of the amendment. Above all, clarifying this is the subject and method of this study, and the scope of the study.

Development of the Common Model for Reuse of GIS Components in Local Governments (재사용을 위한 지자체 GIS 공통모델 연구)

  • Kim, Eun-Hyung
    • Journal of Korea Spatial Information System Society
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    • v.1 no.2 s.2
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    • pp.81-98
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    • 1999
  • The purpose of this study is to provide a common model and implementation strategies for reusing GIS components in local governments. The common model includes several solutions to remove stumbling blocks step by step in reusing or exchanging GIS application systems between local governments. Elements of the model are component architecture, common business process model, common function model, and data model. The elements are the minimum standards for reusability. In order to realize the desirable common model at present, however, the following problems remain : usable components are insufficient in spatial domains and existing GIS application systems require reinvestment to accommodate the new component technology. Three questions are raised to maximize reusability from a monolithic structure toward layered and the componentized GIS application systems : (1) How can the application systems be reused within a local government?, (2) Can the systems be exchanged when they are in the same computing platform?, and (3) When the systems are componentized by standardized interfaces, are the components replaceable between the systems in local governments? Some strategies are presented to accomplish the objectives implicated in the questions. For the actual implementation, several issues such as evaluation procedures for component products, ownership and commercialization issues, will be brought up in the future. Central and local governments, and commercial party need to co-operate each other to maximize the reusability. Reducing overlapping investments in local governments and obtaining competitive component technology in the commercial party should be recognized as critical tasks for the more efficient and economical GIS implementation.

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Postbuckling strength of an axially compressed elastic circular cylinder with all symmetry broken

  • Fujii, Fumio;Noguchi, Hirohisa
    • Structural Engineering and Mechanics
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    • v.11 no.2
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    • pp.199-210
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    • 2001
  • Axially compressed circular cylinders repeat symmetry-breaking bifurcation in the postbuckling region. There exist stable equilibria with all symmetry broken in the buckled configuration, and the minimum postbuckling strength is attained at the deep bottom of closely spaced equilibrium branches. The load level corresponding to such postbuckling stable solutions is usually much lower than the initial buckling load and may serve as a strength limit in shell stability design. The primary concern in the present paper is to compute these possible postbuckling stable solutions at the deep bottom of the postbuckling region. Two computational approaches are used for this purpose. One is the application of individual procedures in computational bifurcation theory. Path-tracing, pinpointing bifurcation points and (local) branch-switching are all applied to follow carefully the postbuckling branches with the decreasing load in order to attain the target at the bottom of the postbuckling region. The buckled shell configuration loses its symmetry stepwise after each (local) branch-switching procedure. The other is to introduce the idea of path jumping (namely, generalized global branch-switching) with static imperfection. The static response of the cylinder under two-parameter loading is computed to enable a direct access to postbuckling equilibria from the prebuckling state. In the numerical example of an elastic perfect circular cylinder, stable postbuckling solutions are computed in these two approaches. It is demonstrated that a direct path jump from the undeformed state to postbuckling stable equilibria is possible for an appropriate choice of static perturbations.

Development of Assessment Methodology for Locally Corroded Pipe Using Reference Stress Concept (참조응력개념을 이용한 국부감육배관 평가법 개발)

  • Lim, Hwan;Shim, Do-Jun;Kim, Yun-Jae;Kim, Young-Jin
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.27 no.7
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    • pp.1200-1209
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    • 2003
  • In this paper, a unified methodology based on the local stress concept to estimate residual strength of locally thinned pipes. An underlying idea of the proposed methodology is that the local stress in the minimum section for locally thinned pipe is related to the reference stress, popularly used in creep problems. Then the problem remains how to define the reference stress, that is the reference load. Extensive three-dimensional finite element (FE) analyses were performed to simulate full-scale pipe tests conducted for various shapes of wall thinned area under internal pressure and bending moment. Based on these FE results, the reference load is proposed, which is independent of materials. A natural outcome of this method is the maximum load capacity. By comparing with existing test results, it is shown that the reference stress is related to the fracture stress, which in turn can be posed as the fracture criterion of locally thinned pipes. The proposed method is powerful as it can be easily generalised to more complex problems, such as pipe bends and tee-joints.

An Experimental Study on the Effect of Fluid Flow and Heat Transfer Characteristics by the Longitudinal Vortices (종방향 와동이 유체유동 및 열전달 특성에 미치는 영향에 관한 실험적 연구)

  • 양장식;김은필
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.12 no.9
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    • pp.843-852
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    • 2000
  • The flow characteristics and the heat transfer rate on a surface by interaction of a pair of vortices were studied experimentally. The test facility consisted of a boundary-layer wind tunnel with a vortex introduced into the flow by half-delta winglet protruding from the surface. In order to control the strength of the longitudinal vortices, the angles of attack of the vortex generators were varied from $\pm20\;degree\;to\;\pm45$ degree, but spacings between the vortex generators were fixed to 4 cm. The 3-dimensional mean velocity measurements were made using a five-hole pressure probe. Heat transfer measurements were made using the thermochromatic liquid to provide the local distribution of the heat transfer coefficient. By using the method mentioned above, the following conclusions were obtained from the present experiment. The boundary layer was thinned in the regions where the secondary flow was directed toward the wall and thickened where it was directed away from the wall. The peak augmentation of the local heat transfer coefficient occurred in the downwash region near the point of minimum boundary-layer thickness.

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Measurements of Velocity Distribution Function in Circular Open Channel Flows by Stereoscopic PIV (3차원 PIV에 의한 원형 개수로 유동의 속도분포 함수 측정)

  • Yoon, Ji-In;Sung, Jae-Yong
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.23 no.5
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    • pp.365-374
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    • 2011
  • For the first time, the present study has measured the velocity distribution function in circular open channel flow in a three-dimensional shape using a stereoscopic PIV system. For a given channel slope, water depth was varied from 30% to 80% of the channel diameter. Then, the characteristics of the velocity distribution function was compared according to the change of the water depth. Unlike a rectangular channel, the present experiment exhibited quite different shapes in the velocity distribution function whether the water depth is higher than 50% or not. Especially, the position of maximum velocity in the central and side wall changes in a different manner for the water depth above 50%. By differentiating the velocity distribution function, local wall friction coefficient was evaluated as a function of wall position. If the water depth goes down, the difference between the maximum and minimum values in the local wall friction coefficient increases, and the averaged value a1so increases.

Simulated Annealing for Reduction of Defect Sensitive Area Through Via Moving (Via 이동을 통한 결함 민감 지역 감소를 위한 시뮬레이티드 어닐링)

  • Lee, Seung Hwan;Sohn, So Young
    • Journal of Korean Institute of Industrial Engineers
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    • v.28 no.1
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    • pp.57-62
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    • 2002
  • The semiconductor industry has continuously been looking for the ways to improve yield and to reduce manufacturing cost. The layout modification approach, one of yield enhancement techniques, is applicable to all design styles, but it does not require any additional resources in terms of silicon area. The layout modification method for yield enhancement consists of making local variations in the layout of some layers in such a way that the critical area, and consequently the sensitivity of the layer to point defects, is reduced. Chen and Koren (1995) proposed a greedy algorithm that removes defect sensitive area using via moving, but it is easy to fall into a local minimum. In this paper, we present a via moving algorithm using simulated annealing and enhance yield by diminishing defect sensitive area. As a result, we could decrease the defect sensitive area effectively compared to the greedy algorithm presented by Chen and Koren. We expect that the proposed algorithm can make significant contributions on company profit through yield enhancement.

Microbiological Quality Assessment of a Local Milk Product, Kwacha Golla, of Bangladesh

  • Rahman, M.M.;Rahman, M.Mashiar;Arafat, S.M.;Rahman, Atiqur;Khan, M.Z.H.;Rahman, M.S.
    • Applied Biological Chemistry
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    • v.51 no.4
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    • pp.251-257
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    • 2008
  • Different types of milk products, such as kwacha golla, mawa, cheese, curd, and chocolate are popular in Bangladesh. However, the microbiological safety of these products is poorly understood. This study was performed to assess the microbiological quality of kwacha golla, a local milk product. Kwacha golla samples were collected from ten different areas of Rajshahi and Kushtia regions, and the quality of the each sample was assessed using various parameters including standard plate count, total coliform, fecal coliform, total fungi, and spore-forming bacteria, as well as food-borne microorganisms. Out of 300 samples, total coliform was detected at 56.66% (n= 300), exceeding the minimum allowable limit of 36.66%. Similarly, experiments were carried out with fungi and food-borne pathogens including Escherichia coli, Listeria monocytogenes, Salmonella sp., and Staphylococcus aureus. Results revealed 85.33, 53, and 49.33% of the samples were contaminated by fungi, E. coli, and L. monocytogenes, respectively. However, all samples showed no contaminations of Salmonella sp. and Staphylococcus sp. Therefore, this study could be helpful to the people of Bangladesh by providing information on the possibility of a major health problem caused by the consumption of kwacha golla.

On-line Vector Quantizer Design Using Stochastic Relaxation (Stochastic Relaxation 방법을 이용한 온라인 벡터 양자화기 설계)

  • Song, Geun-Bae;Lee, Haing-Sei
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.38 no.5
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    • pp.27-36
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    • 2001
  • This paper proposes new design algorithms based on stochastic relaxation (SR) for an on-line vector quantizer (VQ) design. These proposed SR methods solve the local entrapment problems of the conventional Kohonen learning algorithm (KLA). These SR methods cover two different types depending upon the use of simulated annealing (SA) : the one that uses SA is called the OLVQ SA and the other the OLVQ SR. These methods arc combined with the KLA and therefore preserve the its convergence properties. Experimental results for Gauss Markov sources, real speech and image demonstrate that the proposed algorithms can consistently provide better codebooks than the KLA.

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