• Title/Summary/Keyword: initial model

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An Algorithm for Generating' the Hull Structural Analysis Model Using the Seam Information of the Hull Structure at the Initial Design Stage

  • Roh, Myung-Il;Lee, Kyu-Yeul;Yoo, Seong-Jin
    • Journal of Ship and Ocean Technology
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    • v.10 no.4
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    • pp.24-33
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    • 2006
  • So far, the generation of a hull structural analysis model, that is, a finite element model of a hull structure, has been manually performed by a designer using design experience, and thus has required lots of time because of many constraints, the complexity, and the huge size of the hull structure. To make this task automatic, an algorithm for generating the hull structural analysis model is developed using the seam information of the hull structure. A generating system of the hull structural analysis model is implemented based on the developed algorithm. The applicability of the developed algorithm is demonstrated by applying it to the generation of the global and hold structural analysis models of a deadweight 300,000 ton VLCC (Very Large Crude oil Carrier). The results show that the developed algorithm can quickly generate these models at the initial design stage.

Initial QP Modeling for GOP Layer Rate Control (GOP 레이어 비트율 제어를 위한 초기 QP 모델링)

  • Park, Sang-Hyun
    • The Journal of the Korea institute of electronic communication sciences
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    • v.7 no.6
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    • pp.1377-1383
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    • 2012
  • The first frame of a GOP is encoded in intra mode which generates a larger number of bits. In addition, the first frame is used for the inter mode encoding of the following frames. Thus the intial QP for the first frame affects the first frame as well as the following frames. Traditionally, the initial QP is determined among four constant values only depending on the bpp. Although this initialization scheme is simple, yet it is not accurate enough. An accurate intial QP prediction scheme should not only depends on bpp but also on the complexity of the video sequence and the output bandwidth. In this paper, we propose a traffic model for finding the optimal initial QP which maximizes the PSNR of the GOP. We also propose a method to find model parameters for real-time video encoding. It is shown by experimental results that the proposed traffic model captures initial QP characteristics effectively and the proposed method for model parameters accurately estimates the real values.

Evaluation of the Effect of Annular-to-Intermittent Plow Transition Model on the Dryout Model (환상류-간헐류 천이 모텔이 드라이아웃 모델에 미치는 영향 평가)

  • WU S.I.;Im In Cheol
    • 한국전산유체공학회:학술대회논문집
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    • 2004.03a
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    • pp.220-223
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    • 2004
  • The initial conditions such as the film thickness and the void fraction at the onset of annular flow are required for the analytical dryout model. The Disturbance Wave Instability model(DWI model) is one of the model describing the Annular-to-Intermittent Flow regime Transition(AIFT). The experimental CHF conditions for the uniformly heated tube were compared with the predictions by the modified Levy model, for which the initial conditions at AIFT were estimated by the DWI model. For the flow through long tubes with small inlet subcooling, the effect of AIFT model on the dryout prediction was little. However, the use of DWI model gave better prediction of CHF in a short tube.

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Impact of initial damage path and spectral shape on aftershock collapse fragility of RC frames

  • Liu, Yang;Yu, Xiao-Hui;Lu, Da-Gang;Ma, Fu-Zi
    • Earthquakes and Structures
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    • v.15 no.5
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    • pp.529-540
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    • 2018
  • The influences of initial damage paths and aftershock (AS) spectral shape on the assessment of AS collapse fragility are investigated. To do this, a four-story ductile reinforced concrete (RC) frame structure is employed as the study case. The far-field earthquake records recommended by FEMA P695 are used as AS ground motions. The AS incremental dynamic analyses are performed for the damaged structure. To examine the effect of initial damage paths, a total of six kinds of initial damage paths are adopted to simulate different initial damage states of the structure by pushover analysis and dynamic analysis. For the pushover-based initial damage paths, the structure is "pushed" using either uniform or triangle lateral load pattern to a specified damage state quantified by the maximum inter-story drift ratio. Among the dynamic initial damage paths, one single mainshock ground motion or a suite of mainshock ground motions are used in the incremental dynamic analyses to generate a specified initial damage state to the structure. The results show that the structure collapse capacity is reduced as the increase of initial damage, and the initial damage paths show a significant effect on the calculated collapse capacities of the damaged structure (especially at severe damage states). To account for the effect of AS spectral shape, the AS collapse fragility can be adjusted at different target values of ${\varepsilon}$ by using the linear correlation model between the collapse capacity (in term of spectral intensity) and the AS ${\varepsilon}$ values, and coefficients of this linear model is found to be associated with the initial damage states.

A Quality and Pricing Strategy for Web Sites Providing Initial Free Services (초기 무료 서비스를 제공하는 웹사이트의 품질 및 가격전략)

  • Lee Kang-Bae
    • Management & Information Systems Review
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    • v.9
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    • pp.65-80
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    • 2002
  • As the growth of Internet business, many web sites have been developed their own Internet business strategies. Yet, many web sites have difficulties to make profit. In this paper, an economic model is developed to analyze web sites' quality and pricing strategies when they initiate their services as free services and develop advertising services and other charged services. By analyzing the economic model, optimal quality and prices was found. And by analyzing the optimal strategy, I found that web sites should properly decide their market share on initial customer. Finally, the importance of web sites' productivity to make profit is emphasized.

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A new theoretical model for the dynamical analysis of Nano-Bio-Structures

  • Di Sia, Paolo
    • Advances in nano research
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    • v.1 no.1
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    • pp.29-34
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    • 2013
  • The conversion of mechanical energy into electrical energy at nanoscale using piezoelectric nanowire arrays has been in detail shown by deflection of nanowires. Recently it has performed an analytical model, both at classical and at quantum level, for describing the most important quantities concerning transport phenomena; the model predicts interesting peculiarities, as high initial charge diffusion in nanodevices constituting by nanowires and permits also in particular to deduce interesting informations about the devices sensitivity, focusing on the correlation between sensitivity and high initial diffusivity of these materials at nanometric level.

체외충격파를 이용한 결석의 치료

  • 김건상
    • Journal of Biomedical Engineering Research
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    • v.10 no.2
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    • pp.114-116
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    • 1989
  • A method has been proposed for the fully automatic detection of left ventricular endocardial boundary in 2D short axis echocardiogram using geometric model. The procedure has the following three distinct stages. First, the initial center is estimated by the initial center estimation algorithm which is applied to decimated image. Second, the center estimation algorithm is applied to original image and then best-fit elliptic model estimation is processed. Third, best-fit boundary is detected by the cost function which is based on the best-fit elliptic model. The proposed method shows effective result without manual intervention by a human operator.

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Improved Initial Costs Expectation Model based on FPA for Internet Banking System (인터넷 뱅킹 시스템을 위한 개선된 FP 기반 초기 규모 예측 모델)

  • Yun, Gwang Yeul;Yoo, Hae Young
    • KIPS Transactions on Software and Data Engineering
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    • v.3 no.4
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    • pp.139-148
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    • 2014
  • With the development of IT, the financial sector has grown dramatically in Non face-to-face channel. However, because the initial costs calculation model which reflects the characteristics of the financial system does not exist, deteriorating reliability of budget establishment and low-price booking competition appeared. This negative situation leads to degradation of Internet Banking systems and customers who use these financial products have many troubles. Therefore, this paper improves the Initial Costs Expectation Model based on FPA & Expert Judgement Model. And it verified the effectiveness of this model through the regression analysis. As a result, we developed the Initial Costs Expectation Model for Internet Banking systems based on FPA, which is increased in accuracy than existing Cost Expectation Models.

Derivation of an Infiltration Model at the Non-Zero Initial Moisture Condition (초기 함수량을 고려한 침투 모형의 유도)

  • Park, Haen-Nim;Jo, Won-Cheol
    • Journal of Korea Water Resources Association
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    • v.35 no.3
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    • pp.285-294
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    • 2002
  • Infiltration is one of the important processes of the hydrologic cycle determining the distribution of water and has been studied extensively. Various theories and models proposed for this process are usually applicable only when the rainfall intensity is higher than the infiltration capacity. The study by Diskin and Nazimov (1995, 1996) suggested a conceptual infiltration model that comprises two elements. The model can make an reasonable approach to the infiltration process, instead of representing the infiltration as a function of time. The study presented herein improved the existing conceptual infiltration model by an additional consideration of the initial moisture contents. The analysis results for the variation of the infiltration capacity curries for various initial moisture contents demonstrate that the model is more reasonable for the approach to the infiltration process. In addition, the results for the relationship of stormwater events-ponding time are compared with the literature values of that for a number of soil types. The agreement is rather good, leading to the conclusion that the improved model is vapid for describing the infiltration process.

Phenomenological Liquid Film Dryout Model for Upward Flow in Tubes and Annuli (원형 및 환상 채널에 흐르는 수직 상향류의 액막 건조 모델)

  • Hong, Sung-Deok;Chun, Se-Young
    • Proceedings of the KSME Conference
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    • 2001.06d
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    • pp.201-207
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    • 2001
  • We modeled the liquid film dryout(LFD) process for both tube and annulus which have uniformly heated vertical channels. We set phenomenological initial conditions in the model. The initial void fraction on the onset of the annular flow location is derived from the physical chum-to-annular flow criterion with the help of the drift-flux-model. The initial thermodynamic-equilibrium-quality is calculated by iteration with the flow quality to find the onset of the annular-flow location. Present model tends to predict very well at the lower exit quality but under-estimates at the higher exit quality. We found that the prediction error of the present model is gradually bigger as the inlet subcooling approaches near the saturation. We obtained excellent results for both tube and annulus channels as the mean of 0.97 and root-mean-square error of 11% for the number of 3883 experimental data on tubes, and of 0.96 and of 12% for 593 on annuli. The present model extended the applicable range to the relatively low exit quality region than previous LFD models.

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