• 제목/요약/키워드: Feed System

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Food-Feed Systems in Asia - Review -

  • Devendra, C.;Sevilla, C.;Pezo, D.
    • Asian-Australasian Journal of Animal Sciences
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    • 제14권5호
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    • pp.733-745
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    • 2001
  • This review paper discusses the relevance and potential importance of food-feed systems in Asian agricultural systems, and in particular the role and contribution of legumes to these systems. A food-feed system is one that maintains, if not increases, the yield of food crops, sustains soil fertility, and provides dietary nutrients for animals. It involves a cropping pattern within which the feed crop has many beneficial effects without competing for land, soil nutrients and water with the food crops. The agricultural environment is described with reference to the priority agro-ecological zones and prevailing mixed farming systems in Asia. Within these systems, animal production is severely hampered by critical feed shortages which can however, be alleviated by the integration of suitable leguminous forages into the cropping systems. The review also focuses on the role and potential importance of leguminous forages in terms of biodiversity, their uses in farming systems, beneficial effects on animal performance, and draws attention to six case studies in different countries that clearly demonstrate many benefits of developing such food-feed systems. Considerable opportunities exist for widening the use of forage legumes in the development of systems with several complementary advantages (e.g. fenceline, cover crops, fodder banks, forage source and erosion control) to improve the development of sustainable crop-animal systems in Asia.

고속 이송계의 통합설계 (Integrated Design of High-speed Feed Drive Systems)

  • 김민석;정성종
    • 대한기계학회논문집A
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    • 제27권12호
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    • pp.2028-2038
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    • 2003
  • High-speed feed drive systems have been widely used in the manufacturing and semiconductor industries. Specifications for high-speed systems require more advanced capabilities than conventional feed drive systems. It is necessary to devise special design concepts to achieve the level of performance for high-speed feed drive systems. In this paper, an integrated design method is proposed for high-speed feed drive systems in which the interactions between mechanical and electrical subsystems ought to be considered simultaneously during the design process. Based on the integrated design method, a nonlinear optimal design procedure of mechanical subsystems considering the Abbe and radius errors is accomplished through the design process of electrical subsystems satisfying the control stability and the saturation condition of actuators as well as the relative stability. Both mechanical and electrical parameters are considered as design variables. Simulations and numerical case studies show that the integrated design method of high-speed feed drive systems creates results satisfying the desired performances of mechatronic systems.

Relationships Between Feed Intake Traits, Monitored Using a Computerized Feed Intake Recording System, and Growth Performance and Body Composition of Group-Housed Pigs

  • Hyun, Young;Ellis, Mike
    • Asian-Australasian Journal of Animal Sciences
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    • 제13권12호
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    • pp.1717-1725
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    • 2000
  • The objective was to determine the relationship between feed intake levels and patterns, and growth performance and body composition of barrows and gilts using automatic feed intake recording equipment (F.I.R.E.). This system records the time of visits to the feeder and the duration and size of meals for individual animals housed in groups. Ninety-six crossbred pigs were grown from $33.4{\pm}0.51$ to $109.7{\pm}1.39kg$ live weight over a 13-week period. Eight mixed-sex groups of 12 pigs were used and 4 dietary treatments were compared giving 2 pens per treatment. The dietary treatments consisted of corn-soybean meal diets with differing protein levels which ranged from 14.7% to 19% between 30 to 55 kg, from 13.3% to 16.9% between 56 and 85 kg, and from 12.3% to 16.8% for the remainder of the study. Animals were ultrasonically scanned to measure loin-eye area and backfat thickness to estimate carcass fat-free lean content at the beginning and end of the study. Barrows had higher daily feed intake than gilts (2.67 vs. 2.46 kg resp. p<0.05) which was the result of a longer feeder occupation time per visit (4.77 vs. 4.54 min, resp. p<0.05), higher feed consumption rates (30.4 vs. 29.0 g/min, resp. p<0.05), and higher feed intakes per visit (136.9 vs. 126.8 g, resp. p<0.01). Gilts had less backfat and greater loin-eye area than barrows (p<0.05). Diet had no significant effect on growth performance and had limited impact on feeding patterns. Body weight showed high correlations with ADG (r=0.74), feed intake per visit (r=0.51) and feed consumption rate (r=0.69). Positive correlation were also found between daily feed intake and feed intake per visit (r=0.45), feeder occupation time per day (r=0.56), and feed consumption rate (r=0.55), and between daily feed intake and backfat thickness (r=0.32) and feed consumption rate and loin-eye area (r=0.32). There were negative correlations between number of feeder visit per day and daily feed intake (r=-0.54), and between feed intake per visit and number of feeder visits per day (r=-0.43). However, correlations between feed intake traits and carcass traits were generally low. Visits to the feeder were greatest during the morning (0700 to 1100 h) and lowest during the evening and nighttime. These results highlight limited variation among the sexes in feeding patterns and suggest important relationships between feeding behavior and feed intake.

KSR-III 추진기관 추진제 공급배관 수치해석 (Numerical Analysis of KSR-III Main Propulsion System Feedlines)

  • 조인현;오승협;강선일;김용욱
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집E
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    • pp.276-281
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    • 2001
  • The KSR-III Main Propulsion System configuration of the liquid oxygen (LOX) feed line is analyzed. This feed line includes a tighter radius and cavitation venturi for flow mass flow-rate passive control. There were concerns that these configurations might generate a great flow distortion at the engine interface. Also both the pressure drop at the feed line and any presence of separation area are a great concern according to the propellant flow. To resolve these issues, a computational fluid dynamic analysis was conducted to determine the flow field in the LOX feed lines.

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특허분석을 통한 공작기계 이송계의 기술 현황과 발전방향 (The Technical Trend and Future Development Direction of Machine Tools Feed Drive System by Patent Mapping)

  • 은인웅;지현수;이지원
    • 한국정밀공학회지
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    • 제29권5호
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    • pp.510-515
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    • 2012
  • Feed drive systems are used to position the machine tool components carrying the cutting tool and workpiece to the desired location. Hence, their positioning accuracy and speed determine the quality and productivity of machine tools. In this paper, technical trend of machine tools feed drive systems are analyzed by patent mapping. And this paper suggested future development direction of feed drive systems. The analysis is carried out by using problem solution map (PSM) for the applied patent during January 2000 and December 2009 in Korea, Japan, EU and U.S.A.

Determination of safe levels and toxic levels for feed hazardous materials in broiler chickens: a review

  • Jong Hyuk Kim
    • Journal of Animal Science and Technology
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    • 제65권3호
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    • pp.490-510
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    • 2023
  • Feed safety is needed to produce and provide safe animal feeds for consumers, animals, and the environment. Although feed safety regulations have been set for each country, there is a lack of clear feed safety regulations for each livestock. Feed safety regulations are mainly focused on heavy metals, mycotoxins, and pesticides. Each country has different safe levels of hazardous materials in diets. Safe levels of hazardous materials in diets are mostly set for mixed diets of general livestock. Although there is a difference in the metabolism of toxic materials among animals, the safe level of feed is not specific for individual animals. Therefore, standardized animal testing methods and toxicity studies for each animal are needed to determine the correct safe and toxic levels of hazardous materials in diets. If this goal is achieved, it will be possible to improve livestock productivity, health, and product safety by establishing appropriate feed safety regulations. It will also provide an opportunity to secure consumer confidence in feed and livestock products. Therefore, it is necessary to establish a scientific feed safety evaluation system suitable for each country's environment. The chance of outbreaks of new hazardous materials is increasing. Thus, to set up appropriate toxic levels or safe levels in feed, various toxicity methods have been used to determine toxic levels of hazardous materials for humans and animals. Appropriate toxic testing methods should be developed and used to accurately set up and identify toxicity and safe levels in food and feed.

공작기계 계 의 이송방향 동특성에 관한 연구 (Feed Directional Dynamic Characteristics of the Machine Tool System)

  • 이종원;조영호
    • 대한기계학회논문집
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    • 제7권1호
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    • pp.36-45
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    • 1983
  • In order to characterize the machine tool feed-drive dynamics, thread cutting experiments are performed with cutting conditions and slide-way lubrication varied. During the experiments, the carriage, tool post and tail stock accelerations in the feed direction are measured, and analyzed by employing the spectral analysis method. It is found that the tool post vibration in the feed direction during thread cutting operation is mainly due to those of the carriage and the workpiece. Other structure-related vibrations show little effects on the tool post vibration. The characteristics of the carriage vibration is shown to be fairly consistent, except the vibration amplitude, regardless the variations in cutting condition and lubrication within the experimental range. The experimental results suggest that the feeddrive system can be modelled as a 2 DOF damped oscillatory system.

이송계에서 이송중량이 동적정도에 미치는 영향

  • 홍성오;김홍배;조규재
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2002년도 춘계학술대회 논문집
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    • pp.528-535
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    • 2002
  • In order to achieve high precision machine tools, the research for performance enhancement of feed drive systems is required. Development of the high speed feed drive system has been a major issue for the past few decades in machine tool industries. The reduction of the tool change time as well as rapid travel time can enhance the productivity. However, the high speed feed drive system generates more heat in nature, which leads thermal expansion that has adverse effects on the accuracy of machined parts. Stick-slip friction has a great influence on the contouring accuracy of CNC machine tools. In this paper table levitation system has been developed for the stick-slip in a feed drive systems. And also, the driving position is set near the center of the main slideway. From the results, it is confirmed that yaw error and straightness can be improved.

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공작기계설계 지원 시스템 개발 -이송계 서보모터 선정에의 적용 (Development of the Expert system of Selecting a Servo-Motor in Feed Drive Unit of a Machiing Center)

  • 장민제;이수홍;박면웅
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2000년도 추계학술대회 논문집
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    • pp.199-202
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    • 2000
  • In this paper, we developed an expert system that helped a machine-tool designer to select a moderate servomotor of the feed drive unit of a machine tool. With the specification of the drive unit, it searches for the set of servo-motors that have enough torque and power to satisfy the driving condition which the designer defines from the database. me database also contains knowledge and rules, which describe the design process and calculate design parameters of a feed drive. The knowledge-based design support module shows every steps of inference and reason for the solution that it provides.

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한우 및 낙농 단지용 소형 TMR 플랜트 모델 개발(I) (Modeling of a Small Group Scale TMR Plant for Beef Cattle and Dairy Farm in Korea(I) - Development of TMR Plant Model -)

  • 하유신;홍동혁;박경규
    • Journal of Biosystems Engineering
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    • 제34권5호
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    • pp.342-350
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    • 2009
  • Currently TMR feed produced in commercial plant is one of the major source to feed cattle for both beef and dairy farm. However, because of lack of cutting and mixing system for utilizing domestic produced firmly baled round roughage in commercial TMR plant, these commercial TMR feed can not satisfy to farmers both in quality and price points of view. In order to solve these problems, a farm group size TMR plant model was developed in this study. The model plant was consist of round bale receiving and cutting system, pneumatic conveying system for transfer the roughage which was cut at the cutter to TMR mixer through pneumatic conveyor, TMR mixer enable to soften the stiff rice strew and to mix with other ingredients, finished feed bin which can be transfer to either packing system or individual farm, packing system by tycon bag which contains 400 kg unit and bulk unloading system to individual farmer. Also, a simulation model ARENA was applied to the model system in order to evaluate and check the production rate in each unit process and operation rate of total system and to find out if there are any clogged unit system obstructing the smooth flow of the total process flow. Processing cycle for produce one batch of the model plant was less than 30 minutes. Thus, it will take less than four hours for producing 16 tons per day equivalent to 1,000 beef cattle's daily feed.