• 제목/요약/키워드: step feed

검색결과 238건 처리시간 0.023초

난용계의 선택채식과 영양소 공급체계 (Dietary Self-selection and Nutrient Feeding Systems for Egg-type Growing Pullets and Layers)

  • 이규호
    • 한국가금학회지
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    • 제21권2호
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    • pp.101-111
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    • 1994
  • From the observations of dietary self-selection by growing pullets, step-up protein or reverse protein and single-stage low protein pullet feeding systems were developed. They offered another pullet feeding concept that appears to control the body weight effectively and to reduce the consumption of feed and nutrients without impairment of subsequent laying performance. It is obvious from the feed and nutrient consumption pattern of layers fed diets for self-selection of energy, protein and calcium that they have a daily cyclic requirement rather than a constant requirement for nutrients. It seems that a practical self-selective feeding system is needed to meet the daily cyclic requirement for nutrients without consuming an excess of energy and protein at certain times of the day as compared to the complete or single diet where layers have to consume extra energy and protein in the afternoon when they have a specific appetite mainly for calcium.

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스피닝 공정을 이용한 다단 원형 컵 형상의 성형성에 관한 연구 (The Spinnability of Multi-step Cylindrical Cup in Spinning Process)

  • 박중언;한창수;최석우;김승수;나경환
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2001년도 춘계학술대회 논문집
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    • pp.1016-1020
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    • 2001
  • The spinning is a very effective manufacturing technology for short production runs in a variety of sizes and shapes, because it can form the cross-section or tubular parts various shapes. However extensive experimental and analytical research has not been carried out. In this study, and fundamental experiment was conducted to improve productivity with process parameter such as tool path, angle of roller holder(a), feed rate(v) and corner radius of forming roller(Rr). These factors were selected as variables in the experiment because they were most likely expected to have and effect on spring back. The clearance was controlled in order to achieve the precision product which is comparable to deep drawing one. And also thickness and diameter distribution of a multistage cup obtained by shear spinning process were observed and compared with those of a commercial product produced by conventional deep drawing.

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구동 방법에 따른 TFT-LCD의 충전 및 Feed-Though 특성 시뮬레이션 (Charging and Feed-Though Characteristic Simulation of TFT-LCD by Applying Several Driving Method)

  • 박재우;김태형;노원열;최종선
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 추계학술대회 논문집 학회본부 C
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    • pp.452-454
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    • 2000
  • In recent years, the Thin Film Transistor Liquid Crystal Display (TFT-LCD) is used in a variety of products as an interfacing device between human and them. Since TFT-LCDs have trend toward larger Panel sizes and higher spatial and/or gray-scale resolution, pixel charging characteristic is very important for the large panel size and high resolution TFT-LCD pixel characteristics. In this paper, both data line precharging method and line time extension (LiTEX) method is applied to Pixel Design Array Simulation Tool (PDAST) and the pixel charging characteristics of TFT-LCD array were simulated, which were compared with the results calculated by both PDAST In which the conventional device model of a-Si TFTs and gate step method is implemented.

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오차모델을 이용한 공작기계 이송장치의 위치제어 알고리듬 개발 (Development of a Position Control Algorithm for Feed Drives in Machine Tools Using an Error Model)

  • 이건복;길형균
    • 대한기계학회논문집A
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    • 제29권1호
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    • pp.115-123
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    • 2005
  • This paper presents the development of an algorithm for position control of feed drives in machine tools. The algorithm is constructed through an experimental method based on proportional control with a ramp input. In the first step of designing, a tracking-error curve is generated with the proportional control, and then an error model is decided to reduce the tracking error, Next, the output signal of the error model is added to the current error signal to yield the actuating error signal. The effectiveness of the proposed scheme is confirmed through simulation and experiments.

ADI재료의 드릴가공시 가공조건에 따른 절삭특성에 관한 연구 (A Study on the Machinability Characteristics of ADI Materials for the Drilling Conditions)

  • 조규재;전언찬
    • 한국정밀공학회지
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    • 제13권7호
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    • pp.36-44
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    • 1996
  • Drilling tests were carried out austempered ductile cast iron(ADI) to clarify the factors influencing the drilling characteristics of ADI material. The machinability of material was evaluated using high speed steel drill and cobalt contained drill of 6mm diameter. The spheroidal graphite cast iron materials were austemized at 900 .deg. C for 1 hour and then wear was kept at 375 .deg. C for 2 hours. Austempered ductile cast iron contains a great deal of retained austenite which contribustes to an improvement of impact strength. In this paper, machinability of ADI was invastigated by drilling experimentation. The results obtained are as follows:a) Flank wear incresses logarithmically with the increases of cutting time and proportionally with the increases of cutting force. b) Drilling hole number of about 2 times can be educed more step feed than ordinary feed due to the high hardness of ADI material and hardness increasing ascribed to the martensite of retained austenite.

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FEM을 이용한 외부고정구 영향에 의한 골-재형성에 대한 해석 (Analysis of bone-remodeling by the influence of external fixator with FEM)

  • 김영은;이원식
    • 대한기계학회논문집
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    • 제15권2호
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    • pp.436-444
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    • 1991
  • A computational method has been developed to analyze the bone-remodeling induced by external fixator. The method was based on the Finite Element Method (FEM) in combination with numerical formulation of adaptive bone-remodeling theories. As a feed-back control variable, compressive strain and effective stress were used to determine the surface remodeling and internal (density) remodeling respectively. Surface remodeling and internal remodeling were combined at each time step to predict the rel situation. A noticeable shape and density change were detected at the region between two pins and density change was decreased with time increment. At final time step, the shape and density distribution were converged closely to its original intact bone model. Similar change was detected in stress distribution. The altered stress distribution due to the pin and external fixator converged to the intact stress distribution with time.

Pitch Angle Control and Wind Speed Prediction Method Using Inverse Input-Output Relation of a Wind Generation System

  • Hyun, Seung Ho;Wang, Jialong
    • Journal of Electrical Engineering and Technology
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    • 제8권5호
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    • pp.1040-1048
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    • 2013
  • In this paper, a sensorless pitch angle control method for a wind generation system is suggested. One-step-ahead prediction control law is adopted to control the pitch angle of a wind turbine in order for electric output power to track target values. And it is shown that this control scheme using the inverse dynamics of the controlled system enables us to predict current wind speed without an anemometer, to a considerable precision. The inverse input-output of the controlled system is realized by use of an artificial neural network. The proposed control and wind speed prediction method is applied to a Double-Feed Induction Generation system connected to a simple power system through computer simulation to show its effectiveness. The simulation results demonstrate that the suggested method shows better control performances with less control efforts than a conventional Proportional-Integral controller.

스테인레스 강의 미세구멍 드릴링 기술 연구 (A Study on the Micro Hole Drilling of Stainless Steel)

  • 김형국;연규현;송성종
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회A
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    • pp.1517-1521
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    • 2007
  • On this study, technical aspects were reviewed to drill a series of micro holes (${\phi}$0.10) over 200 within a few micron tolerance in diameter and position on the stainless steel material. Dedicated tools & jigs were designed and manufactured and optimum cutting conditions were found. On this micro hole drilling process, guide drill and step feeding were applied to help chip discharge, prevent drill breakage and finally improve the accuracy of positioning and roundness. The processing results indicated that most holes are distributed within a few micron tolerance in diameter and position intervals.

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고정밀 이송을 위한 볼스크류용 체결기구의 특성에 관한 연구 (Characteristics of floating couplings of ball screw for high precision feeding system)

  • 김인찬;박천홍;정윤교;이후상
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1996년도 춘계학술대회 논문집
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    • pp.610-614
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    • 1996
  • As the run out error and misalignment of ball screw connected directly to guide table largely affect the motion accuracy of guideway, floating coupling that releases the table from screw nut except feed and rotational direction is needed todecrease its influences. The purpose of this study is to propose a practical model floating coupling of ball serew for high precision feeding system. The straightness, dynanic characteristics and micro step response of hydrostatic guideway, mounted with three types of coupling fixed type, leaf spring type and hydrostatic type, are tested and compared. From the resuts of experiments, it is proved that a hydrostatic type floating coupling is superior to other couplings and is available to high precision feeding system with ball screw.

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스텐다드 셀의 자동배치 배선시스템에 관한 연구 (A Study on the Automatic Placement and Routing System for Standard Cell)

  • 엄낙웅;강길순;박송배
    • 대한전자공학회논문지
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    • 제24권6호
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    • pp.1049-1055
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    • 1987
  • This paper describes a near-optimal standard cell layout strategy which consists of three consecutives steps` partition, placement, and routing. In the partition step, a given network is torn apart into many subnetworks such that each subnetworks contains as many cells as possible with minimum interocnnections between subnetwork. In the placement step, the conventional string placement algorithm was modified. Also, bonding pads were placed such that their connections to the related cells are shortest. As a result for the tested example, the placement time was saved by 60% and the total routing lengths were saved by more than 20% and substantial improvements in the number of feed-through cell and the track density were obtained. The layout program is coded in PASCAL and implemented on a VAX 11-750/UNIX computer.

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