• Title/Summary/Keyword: draft

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A Study on Development of network draft design on 16 shaft dobby loom (16종광 도비직기에서 네트워크조직의 디자인발전에 관한 연구)

  • 최영자
    • Archives of design research
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    • v.15 no.1
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    • pp.81-92
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    • 2002
  • Through network draft, it′s possible to describe curve draft with main motive in a lobby loom and to fulfill draft design more conveniently thanks to the development of computer device. Network draft was introduced by Alice Schlein, who is an American weaving artist, and I had ever published research paper on "The unfolding and development of network draft using computer dobby system" . The purpose of the next study was to develop the design of network draft while do make a design network draft in a dobby loom with 16 shafts, and could reach follow conclusion as a result of designing a variety of drafts. The initial of 4-end in a loom with 16 shafts was a basic condition to describe more perfect shape in comparison with draft in 8 shafts through the development of network. The development of draft line was essential to deride the pattern of fabric, and the pattern of draft is decided according to selecting key peg plan. Thereby, could get a variety of draft patterns derive from mix key peg plan with initial selected by developing the kind of draft line and applying diverse key peg plan. As for the variation and diversification of draft line, the shape of patters varied depending col the curve extent and connectivity of draft line and the size of curve. The pattern of network draft can be changed infinitely by free round curve of draft line. In addition, a variety of draft designs shall be developed by increasing the number of shaft, enlarging the scale of draft line, and developing more creative draft line.

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Development of a Draft Control System for Tractor Using a Proportional Valve (비례밸브를 이용한 트랙터 견인력제어시스템 개발)

  • Lee, S.S.;Lee, J.Y.;Mun, J.H.
    • Journal of Biosystems Engineering
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    • v.31 no.1 s.114
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    • pp.9-15
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    • 2006
  • Draft control is key technique in plow control system for automation of implement control system. To make the consistent draft force is an essential factor for preventing the reduction of working efficiency by tractor's slip and also improving the working efficiency. Therefore, the purpose of this study is to develop the draft sensor for draft control of plow and evaluate the usability of the algorithm of draft control system using proportional control valve. The developed draft control system could extract the draft force very well regardless of draft condition, change of setting draft force and response time in the response characteristic test. The maximum draft force at 3-Point linkage was 10,000 N and the deviation of the control system was 125.8 N in steady state condition. The developed control system worked very well with regard to the change of draft force in field and even in soil condition with soil reaction. The results of experiment showed the characteristics of response was sufficient to be used as the implement draft control system for tractor using proportional valve.

Electronic-hydraulic Hitch Control System for Agricultural Tractor -Draft Control- (트랙터의 전자유압식(電子油壓式) 히치 제어(制御) 시스템에 관한 연구(硏究)(II) -견인력제어(牽引力制御)-)

  • Yoo, S.N.;Ryu, K.H.;Yun, Y.D.
    • Journal of Biosystems Engineering
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    • v.14 no.4
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    • pp.229-241
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    • 1989
  • The purposes of this study were to develop an electronic-hydraulic draft control system for tractor implements, to investigate the control performance of the system and the possibility of adaptation to the conventional tractor. Experiments were carried out to investigate the responses of the system to the step and sinusoidal inputs in draft control. The effects of control mode, hydraulic flow rate, reference deadband, and proportional constant on control performance of the system were investigated. Moreover, the effects of filtering signals from draft sensor were also investigated. The following conclusions were derived from the study; 1. In draft control, there were hunting problems in controlling the implement without filtering the draft signals. Filtering was performed by a control program of electronic controller and the control performance and stability of the system were improved significantly. 2. For the draft control system operated on on-off control mode, draft was controlled within ${\pm}27-{\pm}55kg_f$ to the reference draft when the hydraulic flow rates were 5-15 l/min. For the draft control system operated on PWM control, draft was controlled within ${\pm}27kg_f$ to the reference draft regardless of hydraulic flow rates. 3. In the frequency responses of the draft control system, control performance on PWM control mode was not better than on on-off control mode because of characteristics of hydraulic valve and drafe sensor. As the hydraulic flow rates increased for the system operated on on-off control mode, the corner frequency of amplitude attenuation increased, but the corner frequency of phase-angle change remained nearly the same. But, the system was unstable beyond the frequency of 3.1 rad/s. 4. The electronic-hydraulic hitch control system developed in this study showed superior control performance, stability and convenience compared to conventional mechanical-hydraulic hitch control system. It is considered to be a superior replacement for the conventional mechanical-hydraulic hitch control system.

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A Study on the revised preliminary draft convention on[Int'l] contracts concluded or evidenced by data message (2차 전자계약예비협약초안에 관한 연구)

  • Oh, Se-Chang
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.20
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    • pp.387-421
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    • 2003
  • On the above, a comparison between preliminary draft conventions and comments by the Int'l Chamber of Commerce, contents of preliminary draft convention, problems and alternative are discussed. The conclusions are as follows thereof : The laws of MLEC and MLES made preparation for electronic era of CISG. But electronic circumstances are more changed than the time of regulation of them. Therefore the business world needs a stand-alone convention dealing broadly with the issues of contract formation in electronic commerce. At last, preliminary draft convention delivered a second round. But the base of the instrument was also MLEC and MLES. The revised preliminary draft convention is much amended beyond preliminary draft convention. At its forty-one sessions, the working group reviewed articles 1-11 of the revised preliminary draft convention presented by the secretariat. The remainder was pending until the time of its forty-two sessions. Therefore, on the base of deliberations and decisions of that sessions and them of thirty-six sessions of UNCITRAL, which will be held on comming november, the draft convention which will be prepared by the secretariate, be re-revised preliminary draft convention. According to review of working group on them, preliminary draft convention will officially be draft convention or revise by secretariate. Under these situations, my points of view on draft convention are as follows : As though e-UCP is used carring out side by side with UCP, after e-CISG making in order to adjust CISG to "on" transaction, it is very easy and prompt for business worked to use CISG with e-CISG. This will facilitate ratification of the CISG. For this case, I already presented contents of e-CISG. It is very important for the preliminary draft convention to deal specially with issues related to electronic contracting or to electronic transaction, because according to which way, its contents and scope of application will be different. But the revised draft convention is regretably compromising both them. Consequently, its contents are very confusing and we could not expect its success. If e-CISG will regulate, it is desirable that, if possible, working group has to make the general rule, and the making of useful, practical, affordable rule for electronic commerce, for example Uniform Customs and Practices for Electronic Commerce(e-UEC) in order to solve the specific practical problems, if any, which business currently faces regarding electronic contracting, has to entrust ICC. If working group want to make e-CISG, it is important not to hesitate and take a significant amount of time.

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Draft Characteristics of Korea Paddy Field by Computer Simulation (시뮬레이션에 의한 한국 논 토양의 경운저항 특성)

  • 이규승;박원엽;우상하
    • Journal of Biosystems Engineering
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    • v.24 no.3
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    • pp.195-208
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    • 1999
  • A computer simulation was carried out to investigate draft characteristics of Korean paddy field for obtaining the basic reference to the selection of optimum moldboard type suitable for Korean paddy field conditions. Cylindrical, cylindroidal, semihelical moldboard plows, and one type of oriental Janggi were used for simulation. A series of soil bin experiments was conducted to compare the experimental results with the predicted drafts from computer simulation using the cylindroidal moldboard plow. The computer model predicted draft force with 1~12% error at 12~16cm plowing depth which is the most conventional plowing depth in the rural area in Korea. Thus, the computer model was considered to be good enough for simulation. Due to the different plowing width of experimental plows, specific draft was selected for comparison by computer simulations. Specific draft of cylindrical moldboard plow was ranged from 3 to 6 N/$\textrm{cm}^2$ according to the soil conditions, plowing speed and plowing depth, 2.5~3.0 N/$\textrm{cm}^2$ for semihelical moldboard plow.

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Application of a Neural Network to Dynamic Draft Model

  • Choi, Yeong Soo;Lee, Kyu Seung;Park, Won Yeop
    • Agricultural and Biosystems Engineering
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    • v.1 no.2
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    • pp.67-72
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    • 2000
  • A dynamic draft model is necessary to analyze mechanics of tillage and to design optimal tillage tools. In order to deal with draft dynamics, a neural network paradigm was applied to develop dynamic draft models. For the development of the models, three kinds of tillage tools were used to measure drafts in the soil bin and a time lagged recurrent neural network was developed. The neural network had a structure to predict dynamic draft, having a function of one-step-ahead prediction. A procedure for network prediction model identification was established. The results show promising modeling of the dynamic drafts with developed neural network.

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ebXML Transport, Routing & Packaging Specification

  • 박찬규
    • Proceedings of the CALSEC Conference
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    • 2001.02a
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    • pp.427-444
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    • 2001
  • ㆍ ebXML Message Services Requirements Specification - Working Draft 26-May-2000, v0.96 · ebXML Message Services Specification - Working Draft 13-Sep-2000, v0.21 ㆍ ebXML Collaboration Protocol Profile and Agreement Specification - Working Draft 24-Jan-2001, v0.29 · ebXML Technical Architecture Security Specification - Working Draft 5-Feb-2001, vl.02(Under development) ㆍ ebXML Message Service Interface Specification - Under development.(omitted)

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Development and Evaluation of Nursing Practice Guidelines for Water Treatment System in Hemodialysis (혈액투석실 투석용수관리를 위한 간호실무가이드라인 개발 및 평가)

  • Kim, Su-Mi
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.18 no.4
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    • pp.463-471
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    • 2011
  • Purpose: The purpose of this study was to develop nursing practice guidelines for water treatment system used in hemodialysis and to evaluate the guidelines by applying them in practice. Method: The first draft for the guidelines was developed based on advice and recommendations obtained from procedure review of critical literature. The draft was modified through evaluation by an expert group and pilot application to practice. The final draft was evaluated by the expert group using the AGREE instrument (Appraisal of Guidelines for Research and Evaluation). Results: For the pilot test using the draft guidelines, 144 samples were collected from the water treatment system and hemodialysis machines. Results showed no bacteria. Endotoxin tests and chemical tests passed the criteria. After revision of the draft guidelines and additions to the draft guidelines, the final draft was confirmed. The quality of the final draft was evaluated by 4 experts using the AGREE instrument. The mean standard score was 76.9% for the 19 items. Conclusion: The clinical guidelines developed in this research can be utilized as systematic and scientific guidelines for water treatment systems used in hemodialysis. In addition, the results of the research can contribute to improving care services.

Internal Flow Characteristics in the Draft Tube of a Francis Turbine

  • Wei, Qingsheng;Zhu, Baoshan;Choi, Young-Do
    • Journal of Advanced Marine Engineering and Technology
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    • v.36 no.5
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    • pp.618-626
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    • 2012
  • Suppression of abnormal flow phenomena in the Francis hydro turbine is very important to improve the turbine performance. Especially, as cavitation and cavitation surge makes serious problems when the turbine is operated in the range of partial flow rate, optimum method of suppressing the abnormal flow characteristics is required necessarily. Moreover, as swirl flow in the draft tube of the Francis turbine decreases pressure at the inlet of the draft tube, suppression of the swirl flow can be an useful method of suppressing the occurrence of cavitation. In order to clarifying the possibility of suppressing the swirl flow by J-Groove in the draft tube, a series of CFD analysis has been conducted in the range of partial load, designed condition and excessive flow rate of a Francis turbine. A kind of J-Groove is designed and applied to the draft tube of the Francis hydro turbine model. The pressure contours, circumferential velocity vectors and vortex core regions in the draft tube are compared by the conditions with or without J-Groove. In addition, a group of data about the velocity in the draft is presented to show the influence of J-Groove.

Numerical Analysis on Changes in Flowrate of Draft Water and Power by Changing Design Parameters of a Long-Distance Water Circulation (저층수 흡입식 광역 순환장치의 설계변수에 따른 배출량 및 소비동력 변화 특성에 대한 수치 해석 연구)

  • Song, Dong-Keun;Hong, Won-Seok;Kim, Young-Cheol;Park, Myong-Ha
    • The KSFM Journal of Fluid Machinery
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    • v.13 no.1
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    • pp.23-28
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    • 2010
  • A draft tube which has impeller to elevate bottom water and spread it over surface of lake water, induces convective circulation of lake water, a Long-Distance Circulation (LDC). Circulation of lake water make stratified water mixed and enhance DO (Dissolved Oxygen) of bottom water. Circulation rate of water is determined by draft rate of the tube, which is dependent on design parameters of the draft tube system, i. e. dimension of impeller and diffuser, inclined angle of impeller, impeller shape, and rotational speed. In this study, change in draft rate and power consumption of circulation equipment was investigated numerically with changing impeller dimension, angle and rotational speed. It was found that flowrate of draft water was increased as the dimensions of draft tube and impeller, and rotational speed and inclined angle of impeller increased. The power consumption was also elevated with increasing parameter values, and final selection of parameter values was made to satisfy target flowrates and power consumption.