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A Study on the Feed Rate Optimization of a Linear Motored Feed Drive System for Minimum Vibrations (Linear Motor 이송계의 진동 최소화를 위한 이송속도 최적화)

  • 최영휴;홍진현;최응영;김태형;최원선
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • pp.321-325
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    • 2004
  • Linear motor feed drive systems have been broadly used in machine tools or precision automatic feed systems. Recently, modem machine tools require high speed and high precision feed drive system to achieve high productivity. Unfortunately, a feed drive system, even though it was optimum designed, may experience severe transient vibrations during high-speed operation if its feed rate control is unsuitable. A rough feed rate curve having discontinuity in its acceleration profile causes a serious vibration problem in the feed slides system. This paper presents a feed rate optimization of a machine tool feed slide system, which is driven by a linear motor, for its minimum vibrations. Firstly, a 4-degree-of-freedom lumped parameter model is proposed for the vibration analysis of a linear motor driven machine tool feed drive system. Next, a feed rate optimization of the feed slide is carried out for minimum vibrations. The feed rate curve optimization strategy is to find out the most appropriate acceleration profile with jerk continuity. Of course, the optimized feed rate should approximate to the desired one as possible. A genetic algorithm with variable penalty function was used in this feed rate optimization.

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Genetics of Residual Feed Intake in Cattle and Pigs: A Review

  • Hoque, M.A.;Suzuki, K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.5
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    • pp.747-755
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    • 2009
  • The feed resource for animals is a major cost determinant for profitability in livestock production enterprises, and thus any effort at improving the efficiency of feed use will help to reduce feed cost. Feed conversion ratio, expressed as feed inputs per unit output, is a traditional measure of efficiency that has significant phenotypic and genetic correlations with feed intake and growth traits. The use of ratio traits for genetic selection may cause problems associated with prediction of change in the component traits in future generations. Residual feed intake, a linear index, is a trait derived from the difference between actual feed intake and that predicted on the basis of the requirements for maintenance of body weight and production. Considerable genetic variation exists in residual feed intake for cattle and pigs, which should respond to selection. Phenotypic independence of phenotypic residual feed intake with body weight and weight gain can be obligatory. Genetic residual feed intake is genetically independent of its component traits (body weight and weight gain). Genetic correlations of residual feed intake with daily feed intake and feed conversion efficiency have been strong and positive in both cattle and pigs. Residual feed intake is favorably genetically correlated with eye muscle area and carcass weight in cattle and with eye muscle area and backfat in pigs. Selection to reduce residual feed intake (excessive intake of feed) will improve the efficiency of feed and most of the economically important carcass traits in cattle and pigs. Therefore, residual feed intake can be used to replace traditional feed conversion ratio as a selection criterion of feed efficiency in breeding programs. However, further studies are required on the variation of residual feed intake during different developmental stage of production.

Effects of Addition of a Mycotoxin Detoxifier in Poultry Feed Containing Different Levels of Aflatoxins on the Performance of Broilers

  • Afzal, M.;Zahid, Saleem
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.7
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    • pp.990-994
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    • 2004
  • Effects of addition of a mycotoxin detoxifier in poultry feed were studied in broilers. Aflatoxins were present in the poultry feed as 28 ppb (normal feed), 78 ppb (contaminated feed) and 170 ppb (highly contaminated feed). The mycotoxin detoxifier was used in 3 concentrations i.e. 1, 3 and 5 kg/ton of feed. Aflatoxins reduced the body weight in broiler chicken and treatment of contaminated feed with low level of detoxifier improved the body weight equivalent to that of normal feed. Higher level of detoxifier proved better than lower level addition in alleviating the effects of highly contaminated feed. Addition of detoxifier also resulted in improvement of FCR to the level of normal feed. Antibody levels against Newcastle disease virus on day 28 of age were significantly lower in chicken fed on contaminated feed. Addition of detoxifier in feed improved the antibody levels in chicken. Mortality was highest in groups given contaminated feed throughout the study period of 7 weeks. Significant mortality was also observed in groups given highly contaminated feed for 2 weeks. Mortality in chicken given detoxifier added contaminated feed was lowest and similar to the group given normal feed. The study shows that mycotoxin detoxifier containing oxyquinol, dichloro-thymol and micronized yeast can effectively neutralize the ill-effects of aflatoxins in poultry feed.

A Study on the Feed Rate Optimization of a Ball Screw Feed Drive System for Minimum Vibrations (볼스크류 이송계의 진동 최소화를 위한 이송속도 최적화)

  • Choi, Young-Hyu;Hong, Jin-Hyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • pp.962-966
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    • 2004
  • Ball screw feed drive systems have been broadly used in machine tools or precision automatic feed systems. Recently, modern machine tools require high speed and high precision and drive system to achieve high productivity. Unfortunately, a feed drive system, even though it was optimum designed, may experience severe transient vibrations during high-speed operation if its feed rate control is unsuitable. A rough feed rate curve having discontinuity in its acceleration profile causes a serious vibration problem in the feed slide system. This paper presents a feed rate optimization of a machine tool feed slide system, which is driven by a ball screw, for its minimum vibrations. Firstly, a 6-degree-of-freedom lumped parameter model was proposed for the vibration analysis of a ball screw driven machine tool feed drive system. Next, a feed rate optimization of the feed slide was carried out for minimum vibrations. The feed rate curve optimization strategy is to find out the most appropriate acceleration profile having finite jerk. Of course, the optimized feed rate should approximate to the desired one as possible. A genetic algorithm with variable penalty function was used in this feed rate optimization.

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A Study on the Feed Rate Optimization of a Ball Screw Driven Machine Tool Feed Slide for Minimum Vibrations

  • Choi, Yong-Hyu;Choi, Hoon-Ki;Kim, Soo-Tae;Choi, Eung-Young
    • 제어로봇시스템학회:학술대회논문집
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    • pp.1028-1032
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    • 2004
  • In order to prevent machine tool feed slide system from transient vibrations during operations, machine tool designers usually adopt some typical design solutions; box-in-box typed feed slides, optimizing moving body for minimum weight and dynamic compliance, and so on. Despite all efforts for optimizing design, a feed drive system may experience severe transient vibrations during high-speed operation if its feed rate control is unsuitable. A rough feed rate curve having discontinuity in its acceleration profile causes a serious vibration problem in the feed slides system. This paper presents a feed rate optimization of a ball screw driven machine tool feed slide system for its minimum vibration. Firstly, a ball screw feed drive system was mathematically modeled as a 6-degree-of-freedom lumped parameter system. Next, a feed rate optimization of the system was carried out for minimum vibrations. The main idea of the feed rate optimization is to find out the most appropriate smooth acceleration profile with jerk continuity. A genetic algorithm was used in this feed rate optimization

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A Study on the Comparative Analysis of Business Performance of Raw Feed and Formula Feed in Fish Aquaculture (어류 양식업에 있어서 생사료와 배합사료 급이방식의 경영성과 비교분석 - 육상수조식 넙치양식을 중심으로 -)

  • Song, Jung-Hun
    • Journal of Fisheries and Marine Sciences Education
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    • v.23 no.3
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    • pp.526-532
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    • 2011
  • The formula feed has been valuated its superiority in the aquaculture industry. However, the fish farmer is preferred the raw feed than the formula feed yet. The objectives of this study are to clarified the reason of lower usage of formula feed in aquaculture. We referred to the literature and the enquete, and inspected on-site for this study. Two types of managements, formula feed-usage or not, were compared and analyzed. The results show that the perception of formula feed are changing even though the quality of formula feed is not clear and the growth efficiency is lower than raw feed, because the domestic supply of raw feed was not smooth and the cost was raised.

The Effect of Food Treated with Gamma Radiation after Inoculation with Pathogenic Bacteria in the Flounder (Paralichthys olivaceus) (넙치에서 방사선을 조사한 병원성 세균 오염사료 투여의 효과)

  • 김세라;김성호
    • Journal of Veterinary Clinics
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    • v.19 no.1
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    • pp.7-13
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    • 2002
  • This study was examined the microbiological adequacy of fish feed treated with high-dose irradiation (5 kGy). 125 flounder (Paralichthys olivaceus) were grouped into 5 and then the fishes were fed the following feeds for 28 days: (1)standard feed; (2)standard feed, inoculated with Edwardsiella tarda ($1{\times}10^8-1{\times}10^9CFU/g$ of feed); (3)standard feed, inoculated with Vibrio anguilarum ($1{\times}10^8-1{\times}10^9CFIT/g$ of feed); (4)standard feed, inoculated with Streptococcus faecalis ($1{\times}10^8-1{\times}10^9CFU/g$ of feed); (5)standard feed, inoculated with Edwardsiella tarda, Vibrio anguillarum and Streptococcus faecalis, and then irradiated the mixed feed to 5 kGy. The flounders feed the mixed diet with Edwardsiella tarda, Wbrio anguillarum or Streptococcus faecalis inoculated feed were showed severe cumulative mortalities of 60, 48 and 52% respectively. The gross and histological changes were observed on the fishes. However, fishs fed with the feed of bacteria inoculation before irradiation demonstrated excellent protection against the bacteria-related disease. The results from experiments with bacteria inoculated feed indicated that the irradiation methods employed were capable of preventing contamination of the fishs with pathogenic bacteria.

Development of the FEED framework of the mineral carbonization pre-treatment system using systems engineering technique (시스템엔지니어링 기법을 이용한 광물탄산화 시스템 FEED 프레임워크 개발 방안에 관한 연구)

  • Kim, Jinil;Yeom, Choongsub;Ryu, BoHyun;Yoon, Munkyu;Kim, Joonyoung
    • Journal of Energy Engineering
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    • v.27 no.1
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    • pp.12-20
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    • 2018
  • The FEED (Frond End Engineering Design) framework defines the activities and outputs to be performed at the FEED stage. In the meantime, many studies on FEED have been carried out, but most of them have slightly different opinions depending on experiences. It is important to define the FEED appropriately for the project and define the activities and outputs that are needed. It is also necessary to develop FEED processes on a solid basis, such as international system engineering process standards rather than experience. In this study, FEED is defined as suitable for the mineral carbonation system development project, and a method for developing the process and output to satisfy it is proposed based on the system engineering standard process.

Assessment of FEED Structure and Functions for Project Management of Thermal Power Plant Construction (사업관리 관점의 FEED 업무 프로세스 구조 및 항목 평가 - 화력발전소를 중심으로 -)

  • Kim, Namjoon;Jung, Youngsoo;Yang, Myungdirk
    • Korean Journal of Construction Engineering and Management
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    • v.16 no.5
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    • pp.65-76
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    • 2015
  • FEED (Front End Engineering and Design) is the key area that determines the competitiveness of procurement and construction in the EPC contracts especially in terms of the added value. Nevertheless, previous researches in FEED have been limited to the process and deliverable of design work or the particular management business function (e.g. System Engineering, collaboration, information etc.). In this context, the purpose of this study is to propose a comprehensive FEED structure and its functions from the project management perspective throughout the whole project life-cycle for thermal power plants. Proposed FEED business procedures are classified into three levels; First level is the classification of FEED business phases, the second level defines major FEED management functions, and the third level is detailed FEED functions. A survey using proposed FEED functions and assessment variable was conducted in order to analyze the current status and the areas for future improvement. It is expected that the proposed structure, functions, and evaluation methodology for FEED management will contribute to effective practice of FEED as well as to improvement of competitive capability for engineering, procurement, and construction (EPC) companies.

Effect of Feed Substrate Thickness on the Bandwidth and Radiation Characteristics of an Aperture-Coupled Microstrip Antenna with a High Permittivity Feed Substrate

  • Kim, Jae-Hyun;Kim, Boo-Gyoun
    • Journal of electromagnetic engineering and science
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    • v.18 no.2
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    • pp.101-107
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    • 2018
  • The impedance bandwidth and radiation characteristics of an aperture-coupled microstrip line-fed patch antenna (ACMPA) with a high permittivity (${\varepsilon}_r=10$) feed substrate suitable for integration with a monolithic microwave integrated circuit (MMIC) are investigated for various feed substrate thicknesses through an experiment and computer simulation. The impedance bandwidth of an ACMPA with a high permittivity feed substrate increases as the feed substrate thickness decreases. Furthermore, the front-to-back ratio of an ACMPA with a high permittivity feed substrate increases and the cross-polarization level decreases as the feed substrate thickness decreases. As the impedance bandwidth of an ACMPA with a high permittivity feed substrate increases and its radiation characteristics improve as the feed substrate thickness decreases, the ACMPA configuration becomes suitable for integration with an MMIC.