• Title/Summary/Keyword: Initial factor

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Innovation Cluster of Indian Software Industry: Is It Evolved or Developed\ulcorner (인도 소프트웨어 산업의 혁신클러스터 형성 과정: 개발인가, 진화인가?)

  • 임덕순
    • Journal of Korea Technology Innovation Society
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    • v.5 no.2
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    • pp.167-188
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    • 2002
  • Summary: This paper analyzes Indian software industry in the perspective of innovation cluster. The research shows that the software industry has been following an upstream clustering process, where the major value activity is expanding from low value product/services to high value product/services. The growth of software industry could be successful because there was appropriate initial condition of Bangalore, such as the availability of high qualified human resources, excellent research institutes, small high-tech companies. The role of government was helpful for the late growth of software industry but not a critical factor for the initial development of the S/W cluster. It is suggested that government should consider the initial condition of a concerned location critically to implement a cluster-type innovation policy.

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A study on rib-web shaped ring forging using UBET (UBET를 이용한 리브-웨브형 링 단조에 관한 연구)

  • Kim, Y.H.;Bae, W.B.;Nam, K.H.
    • Journal of the Korean Society for Precision Engineering
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    • v.11 no.5
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    • pp.134-142
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    • 1994
  • An upper bound elemental technique (UBET) is applied to predict variations of neutral plane and optimal position of the initial billet for rib-wep shaped ring forging. In the analysis, the neutral plane position and velocity fields are determined by minimizing the total power consump- tion with respect to chosen parameters. The degree of die-cavity filling by initial billet-position and the variations of neutral plane by friction condition are investigated. Experiments have been carried out with pure plasticine billets at room temperature. The theoretical predictions of the forging load and the flow pattern are in good agrement with the experimental results.

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Dynamic Analysis of Metal Transfer using VOF Method in GMAW (II) - Short Circuit Transfer Mode - (VOF 방법을 이용한 GMA 용접의 금속 이행에 관한 동적 해석 (II) - 단락 이행 모드의 해석 -)

  • 최상균;고성훈;유중돈;김희진
    • Journal of Welding and Joining
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    • v.15 no.3
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    • pp.47-55
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    • 1997
  • Dynamic characteristics of the short circuit mode are investigated using the Volume of Fluid (VOF) method. When the initial molten drop volume, contact area and wire feed rate are given, rate change of the molten bridge profiles, pressure and velocity distributions are predicted. The electromagnetic force with proper boundary conditions are included in the formulation to consider the effects of welding current. It is found that the molten metal is transferred to the weld pool mainly due to the pressure difference caused by the curvatures in the initial stage, and electromagnetic force becomes dominant factor in the final stage of short circuit transfer. Necking occurs at the contact position between the molten drop and weld pool, and the initial molten drop volume and welding current have significant effects on break-up time.

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Effect of Specimen Thickness to Corrosion Fatigue Crack Propagation Behavior of Structure Rolled Steel (일반구조용 압연강재의 부식피로균열전파거동에 미치는 시험편 두께의 영향)

  • 조약래
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.28 no.3
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    • pp.286-294
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    • 1992
  • In this paper, the corrosion fatigue crack propagation behavior of structure rolled steel (SWS 41C) was investigated by changing the thickness, and this experiment was done by the three point bending corrosion fatigue tester. The main results obtained are as follows: 1) As the thickness of specimen becomes thicker, the corrosion sensitivity to initial stage crack becomes some sensitive, and that the fatigue life becomes more sensitive. 2) The crack growth rate to initial stage crack (da/dN) was retarded as the thickness of specimen becomes thicker. But after initial stage crack, as the thickness of specimen is more thicker, da/dN is more rapid. 3) As the corrosion fatigue crack length grows, the accelerative factor of thick specimen (t=12mm) is more higher than that of thin specimen (t=6mm). 4) As the corrosion fatigue crack length grows, the corroson potential of both thick specimen and thin specimen becomes more less noble potential, however thick specimen (t=12mm) tends to more less noble potential than that of thin specimen(t=6mm).

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Study of Factors Influenced on denitrification in wastewater treatment (폐수처리 탈질 공정에 미치는 인자 연구)

  • Jeong, Gwi-Taek;Park, Seok-Hwan;Park, Jae-Hee;Bhang, Sung-Hun;Lim, Eun-Tae;Park, Don-Hee
    • KSBB Journal
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    • v.23 no.6
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    • pp.535-540
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    • 2008
  • In this study, the effects of several factors such as initial nitrate concentration, C/N ratio, biomass amount and external carbon source on denitrification process were investigated using synthetic wastewater and sludge obtained from wastewater treatment facility. As a result, the condition of lower initial nitrate concentration was increased to the removal rate of nitrate than that of high concentration. The increases of C/N ratio and initial biomass amount were linearly enhanced the removal rate. The use of ethanol as external carbon source was shown the highest removal yield than that of others.

-An Application of Simulated Annealing for an FMS Disatching Priority Problem (유연생산시스템의 투입우선순서결정을 위한 Simulated Anneaing의 적용)

  • 이근형;황승국;이강우
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.23 no.54
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    • pp.77-85
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    • 2000
  • One form of job shop scheduling problem in contemporary automated manufacturing such as flexible manufacturing systems (FMS's) is presented which we call the FMS dispatching priority problem. The FMS dispatching priority problem seeks the best dispatching priority of parts and operations, and is essentially a combinatorial optimization problem. Because of the complicated mechanism of the system, the performance of a given dispatching priority must be evaluated via simulation. Simulated annealing have been applied to the problem, and it is found that appropriate parameter setting will be desirable to get good, if not the optimal, solutions within a limited amount of time under the presence of heavy computational burden due to simulation. More specifically, experiments reveal that initial temperature is the single most important factor among other parameters and factors, and that the appropriate initial temperature depends on the allowable computer time in such a way that the less time one can afford to spend, the lower the appropriate initial temperature should be.

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Effect of Cobalt Substitution on the Magnetic Properties of NiZnCu Ferrite for Multilayer Chip Inductors (Cobalt 치환된 칩인덕터용 NiZnCu Ferrite의 자기적 특성 연구)

  • An, Sung-Yong;Kim, Ic-Seob;Son, Soo-Hwan;Song, So-Yeon;Hahn, Jin-Woo;Choi, Kang-Ryong
    • Journal of the Korean Magnetics Society
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    • v.20 no.5
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    • pp.182-186
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    • 2010
  • Effect of cobalt substitution on the sintering behavior and magnetic properties of a NiZnCu ferrite was studied. $Ni_{0.36-x}Co_xZn_{0.44}Cu_{0.22}Fe_{1.98}O_4(0{\leq}x{\leq}0.04)$ ferrite was fabricated by a solid stat reaction method. It was proposed and experimentally verified that $Co^{2+}$ substituted NiZnCu ferrite was effective on improving the quality factor and magnetic properties of NiZnCu ferrites for multilayer chip inductors. The ferrite was sintered without sintering aids, at $880{\sim}920^{\circ}C$, for 2 h and the initial permeability, quality factor, density, shrinkage, saturation magnetization, and coercivity were also measured. The quality factor (Q) was increased linearly up to x = 0.01 and decreased rapidly over x = 0.01. As the cobalt content increased, the initial permeability and density of the ferrites decreases. The initial permeability of toroidal sample for $Ni_{0.35}Co_{0.01}Zn_{0.44}Cu_{0.22}Fe_{1.98}O_4$ ferrites sintered at $900^{\circ}C$ was 130 at 1 MHz and quality factor was 230.

Feasibility Analysis of the Bridge Analytical Model Calibration with the Response Correction Factor Obtained from the Pseudo-Static Load Test (의사정적재하시험 응답보정계수에 의한 교량 해석모델 보정의 타당성 분석)

  • Han, Man-Seok;Shin, Soo-Bong
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.25 no.6
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    • pp.50-59
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    • 2021
  • Currently, the response correction factor is calculated by comparing the response measured by the load test on a bridge with the response analyzed in the initial analytical model. Then the load rating and the load carrying capacity are evaluated. However, the response correction factor gives a value that fluctuates depending on the measurement location and load condition. In particular, when the initial analytical model is not suitable for representing the behavior of a bridge, the range of variation is large and the analysis response by the calibrated model may give a result that is different from the measured response. In this study, a pseudo-static load test was applied to obtain static response with dynamic components removed under various load conditions of a vehicle moving at a low speed. Static response was measured on two similar PSC-I girder bridges, and the response correction factors for displacement and strain were calculated for each of the two bridges. When the initial analysis model was not properly set up, it is verified that the response of the analytical model corrected by the average response correction factor does not fall within the margin of error with the measured response.

Fatigue life evaluation for fuselage structure using equivalent unit load (등가 단위하중을 이용한 동체 구조물 피로수명 평가)

  • Kim, Sung-Joon;Ahn, Seok-Min;Yeom, Chan-Hong
    • Aerospace Engineering and Technology
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    • v.8 no.2
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    • pp.13-18
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    • 2009
  • In this study, an equivalent unit load methodology has been presented to simplify the fatigue analysis procedure. And fuselage structure fatigue life has been evaluated based on equivalent unit load. Finite element analysis has been carried out to analyze the stress intensity factor and geometrical correction factor that is needed for crack growth analysis. And strain energy density factor is used to predict the initial direction of crack propagation.

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A bimodal Weibull distribution - capacity factor for different heights at sulur

  • Seshaiah, C.V.;Indhumathy, D.
    • Wind and Structures
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    • v.28 no.1
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    • pp.63-70
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    • 2019
  • Due to developing environmental concern use of renewable energy source is very essential. The great demand for the energy supply coupled with inadequate energy sources creates an emergency to find a new solution for the energy shortage. The appropriate wind energy distribution is the fundamental requirement for the assessment of wind energy potential available at the particular site essential for the design of wind farms. Hence the proper specification of the wind speed distribution plays a vital role. In this paper the Bimodal Weibull distribution is used to estimate the Capacity factor at the proposed site. The shape and scale parameters estimated using Maximum likelihood method is used as the initial value for extrapolation. Application of this model will give an accurate result overwhelming the concept of overestimation or underestimation of Capacity factor.