• Title/Summary/Keyword: Sizing method

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A NEW CELL SIZING METHOD FOR AUTOMATIC UNSTRUCTURED GRID GENERATION USING CAD SURFACE DATA (CAD 형상 데이터를 이용한 비정렬 격자 자동 생성을 위한 격자셀 크기 지정 기법)

  • Lee, B.J.;Kim, B.S.
    • 한국전산유체공학회:학술대회논문집
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    • 2007.10a
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    • pp.120-125
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    • 2007
  • In this paper a new cell sizing method is proposed. The new method calculates cell size at a point using given size control elements directly without the aid of background grid as other cell sizing algorithms do. The calculation method and related definitions are described in detail, and typical cell sizing results are given.

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The Study on Hardware Sizing Method Based on the Calculating (계산에 기초한 하드웨어 도입 규모산정 방식 연구)

  • Ra, Jong-Hei;Choi, Kwang-Don;Jung, Hae-Yong
    • Journal of Information Technology Services
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    • v.5 no.1
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    • pp.47-59
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    • 2006
  • According to the policy for "e-Korea construction" of Korean government, Investment of information system during the past decade are dramatically increasing. More than a half of this investment is cost of hardware infrastructure. So, accurate hardware sizing are essential for higher efficiency of investment. Accurate hardware sizing benefits are generally viewed in terms of the avoidance of excess equipment and lost opportunity costs by not being able to support business needs. Unfortunately, however, little research effort to make the hardware sizing methodology are doing. We propose a sizing method for information system in public sector. This method is determinate empirical study that are gathering and analyzing cases, making method and reviewing expert. Finally we are proposed calculating method for hardware components that is CPU, memory, internal and external disk according to the application system type which is OLTP, Web, WAS. Our study certainly will act as a catalyst for higher investment-efficiency of the future information programs in public sector.

Theoretical Study of Coherent Acoustic Inverse Method for Bubble Sizing in Bubbly Water

  • Choi, Bok-Kyoung;Yoon, Suk-Wang
    • The Journal of the Acoustical Society of Korea
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    • v.15 no.4E
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    • pp.3-8
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    • 1996
  • The bubble size distribution is critical information to understand sound propagation and ambient noise in the ocean. To estimate the bubble size distribution in a bubbly water, the sound attenuation has been only in the conventional acoustic bubble sizing method without considering the sound speed variation. However, the effect of the sound speed variation in bubbly water cannot be neglected because of its compressibility variation. The sound attenuation is also affected by the sound speed variation. In this paper, a coherent acoustic bubble sizing inverse technique is introduced as a new bubble sizing technique with considering sound speed variation as well as the sound attenuation. This coherent sizing method is theoretically verified with the bubble distribution functions of single-size, Gaussian, and power-law functions. Its numerical test results with the coherent acoustic bubble sizing method show good agreement with the given bubble distributions.

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Assessment of Acoustic Iterative Inverse Method for Bubble Sizing to Experimental Data

  • Choi, Bok-Kyoung;Kim, Bong-Chae;Kim, Byoung-Nam;Yoon, Suk-Wang
    • Ocean Science Journal
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    • v.41 no.4
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    • pp.195-199
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    • 2006
  • Comparative study was carried out for an acoustic iterative inverse method to estimate bubble size distributions in water. Conventional bubble sizing methods consider only sound attenuation for sizing. Choi and Yoon [IEEE, 26(1), 125-130 (2001)] reported an acoustic iterative inverse method, which extracts the sound speed component from the measured sound attenuation. It can more accurately estimate the bubble size distributions in water than do the conventional methods. The estimation results of acoustic iterative inverse method were compared with other experimental data. The experimental data show good agreement with the estimation from the acoustic iterative inverse method. This iterative technique can be utilized for bubble sizing in the ocean.

A Study on Improvement of OLTP Server Sizing Method (OLTP서버 규모산정방식의 개선에 관한 연구)

  • Ra, Jong-Hei;Choi, Kwang-Don
    • Journal of Information Technology Services
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    • v.8 no.3
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    • pp.185-195
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    • 2009
  • Hardware sizing is determinated by an increasing rate of operated business and characteristic of adapted technology which are imported systems. Because it is very difficult for intuitive decision of hardware sizing's appropriateness. But in sprite of difficulty, for maximizing the utilization of information resource and the effect of information investment in public sector are need to correctness hardware sizing. In this paper, we proposed hardware sizing method for OLTP server that is make up It's faults of proper proposal method. Our study certainly will act as a catalyst for higher investment-efficiency of future information systems in public sector.

New Sizing System Development of Korean Male Military Winter Jacket (한국 남자 군인 방한복의 신 치수체계 개발)

  • Han, Hyunsook;Han, Hyunjung;Cho, Jayoung;Jung, Kihyo;Kim, Beomjoon;Koh, Joonseok;Park, Changkyu
    • Journal of the Korean Society of Clothing and Textiles
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    • v.40 no.5
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    • pp.954-965
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    • 2016
  • This study was designed to help develop an optimized sizing system for the military winter jackets of Korean males. First, we conducted a survey on the supply rate of military winter jackets and the wearing of suitable size jackets in order to identify problems in the current sizing system. We next developed a new sizing system generation method to satisfy the coverage rate and appropriate size number: Hybrid of Grid with Optimization. The findings of this study were: 1. The survey indicated that a 90 (chest girth) size is necessary; in addition, a one-step large size jacket fit well as a right size jacket. 2. We developed three optimized sizing systems for Korean male military winter jackets using the Hybrid of Grid with an optimization method and suggested one of them as a final new sizing system. The new sizing system consisted of two primary dimension: chest girth and stature. It has a 14 size number and its extended coverage rate is larger than the current sizing system and it has a 90 (chest girth) size. It also selected an optimized size for the area of low population density. The new sizing system is therefore considered very effective for Korean male soldiers military winter jackets.

An Exploratory Study on Capacity Sizing Method for Information System: Focus on H/W Sizing in Pubic Sector (정보시스템 용량산정방식에 관한 탐색적 연구: 공공부문 H/W 규모산정을 중심으로)

  • Ra, Jong-Hei;Choi, Kwang-Don
    • Journal of Information Technology Services
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    • v.3 no.2
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    • pp.9-23
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    • 2004
  • Interest about Information infrastructure construction is enlarged socially according to arrival of information age, and various information systems are constructed for efficient business processing, customer service in public sector. According to subjective method for performance improvement for information system of public sector and engine that propel information system construction because it is no definite hardware sizing guidelines for information system caterer, is calculating resource volume of information system. It is situation that problem of excess of scale or reduce sizing is happening and is causing various kind of problems that is waste of information budget and service decline thereby. In this research, we proposed hardware sizing framework for information system that is applied to pubic sector.

New Approaches to Flaw Classification and Sizing for Quantitative Ultrasonic Testing (정량적 초음파 시험을 위한 결함분류와 크기산정의 새로운 기법)

  • 송성진
    • Journal of the Korean Society of Safety
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    • v.12 no.2
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    • pp.3-16
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    • 1997
  • In modern high performance engineering applications, the structural integrity of materials and structures are quite often evaluated using fracture mechanics. This evaluation in turn requires information on the flaw geometry (location, type, shape, size, and orientation). The ultrasonic nondestructive evaluation (NDE) method is one technique that is commonly used to provide such information. Flaw classification (determination of the flaw type ) and flaw sizing (prediction of the flaw shape, orientation and sizing parameters) are very important issues for quantitative ultrasonic NDE. In this paper new approaches to both classification and sizing of flaws are described together with extensive review of previous works on both topics. In the area of flaw classification, a methodology is developed which can solve classification problems using probabilistic neural networks, and in the area of flaw sizing, a time-of-flight equivalent (TOFE) sizing method is presented. The techniques proposed here are in a form that can be used directly in many practical applications to quantitative estimates of the flaw's significance.

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FEM Analyses of Hot Forging and Cold Sizing of a Spur Gear (스퍼어기어의 열간단조와 냉간사이징의 유한요소해석)

  • 박종진;이정환
    • Transactions of Materials Processing
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    • v.5 no.2
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    • pp.105-114
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    • 1996
  • Recently, precision forging techniques are applied to manufacture spur gears. Compared to conventional machining, they produce parts of better mechanical properties and less residual stresses with a much higher production rate. In the present investigation a rigid-plastic three dimensional finite element method was applied to analyze hot forging and cold sizing of a spur gear by closed dies. The involute curve of a tooth profile was approximated by a circle close to the curve. Results of the analyses make it possible to predict local strengths of the gear die failure and an appropriate preform for cold sizing. It was found that the preform for cold sizing. It was found that the preform for the cold sizing is the most important because it determines whether the gears especially teeth can be successfully formed.

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The Effect of Second Order Refraction on Optical Bubble Sizing in Multiphase Flows

  • Qiu, Huihe;Hsu, Chin-Tsau;Liu, Wei
    • Journal of Mechanical Science and Technology
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    • v.15 no.12
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    • pp.1801-1807
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    • 2001
  • In multiphase flne the bubble size and velocity. To achieve this, one of approaches is to utilize laser phase-Doppler anemometry. However, it was found that the second order refraction has great impact on PDA sizing method when the relative refractive index of media is less than one. In this paper, the problem of second order refraction is investigated and a model of phase-size correlation to eliminate the measurement errors is introduced for bubble sizing. As a result, the model relates the assumption of single scattering mechanism in conventional phase-Doppler anemometry. The results of simulations based on this new model by using Generalized Lorenz Mie Theory (GLMT) are compared with those based on the conventional method. An optimization method for accurately sizing air-bubble in water has been suggested.

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