• Title/Summary/Keyword: purpose

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A Study on the Development of General Purpose Program for the Analysis of 3-D Fluid Flow by Using a General non-Orthogonal Grid System (일반 비직교좌표계를 사용하는 3차원 범용 유동해석 프로그램의 개발)

  • 허남건;조원국;김광호
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.18 no.12
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    • pp.3345-3356
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    • 1994
  • A general purpose program, TURBO-3D, for the analysis of 3-D fluid flow in complex geometry has been developed, which employs a standard $k-\varepsilon$ turbulence model and a general nonorthogonal grid system. For the purpose of verification of the program and testing the applicability, turbulent flows in an S-shaped diffuser and turbulent flows over an backward facing step are solved and compared with the earlier results. Comparison with the results by the STAR-CD program has been also made for the same flow configuration and grid structure. The agreements are excellent and hence the program has been verified. Since the present program is applicable only on limited flow phenomena and lacks the pre-and post processor, further improvements toward these directions are being made.

Development of a Robotic Surgery System using General Purpose Robotic Arm and Modular Haptic Controller (범용 로봇팔과 모듈러 햅틱 컨트롤러를 사용한 수술 로봇 시스템 개발)

  • Yi, Jae-Bong;Jin, Sangrok;Yi, Seung-Joon
    • The Journal of Korea Robotics Society
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    • v.15 no.2
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    • pp.131-138
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    • 2020
  • This paper proposes a low-cost robotic surgery system composed of a general purpose robotic arm, an interface for daVinci surgical robot tools and a modular haptic controller utilizing smart actuators. The 7 degree of freedom (DOF) haptic controller is suspended in the air using the gravity compensation, and the 3D position and orientation of the controller endpoint is calculated from the joint readings and the forward kinematics of the haptic controller. Then the joint angles for a general purpose robotic arm is calculated using the analytic inverse kinematics so that that the tooltip reaches the target position through a small incision. Finally, the surgical tool wrist joints angles are calculated to make the tooltip correctly face the desired orientation. The suggested system is implemented and validated using the physical UR5e robotic arm.

Understanding Coal Gasification and Combustion Modeling in General Purpose CFD Code (범용 CFD 코드에서 석탄 가스화 및 연소 모델링에 관한 이해)

  • Lee, Hoo-Kyung;Choi, Sang-Min;Kim, Bong-Keun
    • Journal of the Korean Society of Combustion
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    • v.15 no.3
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    • pp.15-24
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    • 2010
  • The purpose of this study is to assess approaches to modeling coal gasification and combustion in general purpose CFD codes. Coal gasification and combustion involve complex multiphase flows and chemical reactions with strong influences of turbulence and radiation. CFD codes would treat coal particles as a discrete phase and gas species are considered as a continuous phase. An approach to modeling coal reaction in $FLUENT^{(R)}$, selected in this study as a typical commercial CFD code, was evaluated including its devolatilization, gas phase reactions, and char oxidation, turbulence, and radiation submodels. CFD studies in the literature were reviewed to show the uncertainties and limitations of the results. Therefore, the CFD analysis gives useful information, but the results should be carefully interpreted based on understandings on the uncertainties associated with the modelings of coal gasification and combustion.

A Development of General Purpose Program NUFLEX for the Analysis of Heat/Fluid Flow (범용 열/유체 유동해석 프로그램 NUFLEX의 개발)

  • Hur N.;Won C.-S.;Son G.;Ryou H.-S.;Shin D.
    • 한국전산유체공학회:학술대회논문집
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    • 2004.10a
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    • pp.53-59
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    • 2004
  • A general purpose program NUFLEX for the analysis of 3-D heat/fluid flow in complex geometry with pre/post processor have been developed, which consists of a flow solver based on FVM and a dedicated pre/post processor. The program employs a general non-orthogonal grid system and solve laminar and turbulent (lows with standard and RNG $\kappa-\epsilon$ turbulence models. NUFLEX is capable of analysing two-phase flow with topologically complex interface, turbulent diffusion combustion, solidification problems and magnetic flow. For the purpose of verification of the program and testing the applicability, several practical problems are solved and compared with the available data. Comparison of the NUFLEX results with that by the STAR-CD program has been also made for the same flow configuration and grid structure.

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A Study for the Magnetic Loading and Electric Loading Ratio of AC Induction Motor for Traction Purpose (AC 견인용 유도전동기의 장하비에 관한 연구)

  • 권중록;박정태;이갑재;이정일;김기찬;이종인;김연달
    • Proceedings of the KSR Conference
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    • 2000.11a
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    • pp.674-679
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    • 2000
  • Designing of the squirrel cage AC Traction Motor has many difficulties which has to be small size in order to be suitable into bogie frame, high efficiency and light weight. It means that induction motor for tractive purpose has to be different magnetic and electric loading ratio from industrial induction motor. This paper is devoted to an examination of how this ratio affects overall design concept and hence the main design points for traction motor. Also studied is tile changed coefficients of the magnetic and electric loading ratio squirrel cage induction motor for the traction purpose which has been already identified from tile reference book for industrial purpose induction motor.

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Using Status of Computer and Internet in University Students (대학생들의 컴퓨터 및 인터넷 이용 실태)

  • Roh, Hyol-yun
    • Journal of Korean Clinical Health Science
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    • v.4 no.2
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    • pp.566-570
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    • 2016
  • Purpose. The purpose of this study was to determine the using state of computers and internet in university students. Method. This research conducts a survey of 50 university students. Researcher personally visited lecture room to explain the purpose of research. The questionnaire was made by the researcher and consists of seven questions. Result. In this study, university students of 74% using computer more than one hour per day. The most of purpose of internet use was internet surfing and writing a document. University students of 42% were play games with internet. Conclusion. The continuous tracking is need of computer and internet use and need to be healthy for the use of guidance of university students.

Achitectural acoustic design for multi-purpose hall of J science museum (J 과학관(科學館) 다목적(多目的) 강당(講堂)의 건축음향설계(建築音響設計))

  • Kim, Dae-Goon;Choi, Dool;Kim, Jae-Soo
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2008.04a
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    • pp.303-307
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    • 2008
  • For the recently constructing building, diverse forms of attempt are being applied with the environmental-friendly design and reflection of the design factor by environment simulation. Especially, in case of Multi-Purpose Hall, in view of its use-purpose and because of the characteristics that should be utilized as the multipurpose uses by well-mingled together with the lecture-wise factor and musical factor, now it could be said that the sufficient examination and planning with regard to the acoustic factor are essential. On such viewpoint, as the object of practically planning multipurpose auditorium, this Study has intended to design such auditorium equipped with the optimal architectural acoustic factor, for the acoustic condition using Acoustic Simulation Technique at the planning stage.

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A study on a multi-purpose sampling design involving both a farm population survery and a livestock survey (농업 기본통계 및 가축통계 조사 標本設計에 관한 연구)

  • 박홍래
    • The Korean Journal of Applied Statistics
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    • v.1 no.1
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    • pp.12-20
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    • 1987
  • This paper aims at studing on a multi-purpose sampling design involving both a farm population survey and a livestock survey. Some features of this design are firstly to equalize the sampling errorsamong Shi-Gun (county) estimates, secondly, to make an efforts to increase the precision by introducing a purpose sample into the probability sample. There are two types of purpose samples according to sampling units; one is farm, the otheris enumeration district. A criterion of demarcation for selecting the farm purposesamle was investigated.

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Feasibility Assessment of Small Hydro Power Plants Using Diversion Weirs for Agricultural Purpose (농업용 보를 이용한 소수력발전소의 타당성 분석)

  • Lee, Chul-Hyung;Park, Wan-Soon
    • 한국태양에너지학회:학술대회논문집
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    • 2011.04a
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    • pp.229-234
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    • 2011
  • Feasibility assessment for small hydropower plants using diversion weirs located in stream for agricultural purpose has been studied. The model, which can predict flow duration characteristic of stream, was developed to analyze the inflow caused from rainfall. And another model to predict hydrologic performance for small hydropower plants is established. Preliminary survey was performed identifying several candidate sites, and two sites were selected finally for actual site reconnaissance. During the course of site survey, generating capacity, construction and equipment cost, and payback through life time of each sites were calculated for economical feasibility analysis. The results of this study have estimated that the small hydropower plants using diversion weirs for agricultural purpose may offer better opportunities in future with increasing fuel cost and nation's energy policy.

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A Study on the Dietrary Attitude of the House Wives in Pusan by Nutrition Knowledge, Purpose Value of Meals and Monthly Food Expenditure (부산지역 일부 주부들의 영양지식, 식생활가치관 및 식생활비에 따른 식행동 조사)

  • 김갑순
    • The Korean Journal of Food And Nutrition
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    • v.12 no.3
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    • pp.300-305
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    • 1999
  • The purpose of this survey was to study nutrition knowledge dietary attitude purpose value of meal and monthly food expenditure in the house wives. The survey was conducted from September 1 to October 20 in 1998. The results were summarized as follows. Nutrition knowledge of the 30s and 40s group were higher than that of the other group. Dietary attitude of the 20s group was lower than that of the other wives. House wives tended to choose food for the pleasure of its taste and intake of nutrients. There was a significant positive correlation between nutrition knowledge and dietary attitude. The diet-ary attitude and nutrition knowledge were significant positive correlations with food diversity. There was negative correlation between age and nutrition knowledge.

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