• Title/Summary/Keyword: feed-through

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Modeling of Pervaporation Process: Prediction of Feed Temperature Distribution in A Frame and Plate Type of Membrane Module (판틀형 투과증발 막모듈내에서 feed 온도 분포 예측을 위한 모델링)

  • 원장묵;염충균;임지원;배성렬;하백현
    • Membrane Journal
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    • v.6 no.1
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    • pp.44-52
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    • 1996
  • For the purpose of the optimal design of a frame and plate type of pervaporation module, model equations which can predict the effects of feed flow condition on the temperature distribution of the feed developed in the module were established and the temperature distribution with feed flow condition was investigated through the model si$$\mu$ation. With increasing the Reynolds number of feed flow in the module, the flow velocity gradient in the channel height-direction as well as the volume rate of feed which acts as energy source for the evaporation of perrneants on the permeate-side surface of a membrane increased to such an extent that both mass and heat flux in the channel height direction could increase and the temperature drop of feed due to the evaporation of the permeant could be reduced correspondingly. A decrease in channel height caused the temperature drop of feed because of decreasing feed flow in the module. It was observed that the si$$\mu$ation result on the effect of Re on the temperature distribution of feed in the module has an agreement with experiment.

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Feed Water Flow Control of Super Critical Once Through Boiler in Korea Standard Power Plant (한국표준형 초 임계압 관류형 보일러의 급수제어)

  • 김은기;장용창;조수현
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.251-251
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    • 2000
  • Tangjin Power Plant is modern Korean standard plant which is made up Once Through Super Critical Boiler, Turbin, Generator and Flue Gas Desulfarization System. INFI-90 system fur control of the 500 MW Korean standard super critical once through boiler Mark-V for Turbine, EX-2000 fer Generator, WDPF for FGD were installed in Tangiin thermal power plant. There were two BFPTs, BFPM, 25% control valve, 35% control valve to control boiler feed water flow. It is very difficult to tune the Separator Tank level control system and change the mode from Wet to Dry. This paper focuses on test results and modification control logic for feed water control system in Tangjin power plant.

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A REVIEW OF THE MICROBIAL DIGESTION OF FEED PARTICLES IN THE RUMEN

  • McAllister, T.A.;Bae, H.D.;Yanke, L.J.;Cheng, K.J.;Ha, J.K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.7 no.3
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    • pp.303-316
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    • 1994
  • Microbial digestion of feed in the rumen involves a sequential attack culminating in the formation of fermentation products and microbial cells that can be utilized by the host animal. Most feeds are protected by a cuticular layer which is in effect a microbial barrier that must be penetrated or circumvented for digestion to proceed. Microorganisms gain access to digestible inner plant tissues through damage to the cuticle, or via natural cell openings (e.g., stomata) and commence digestion from within the feed particles. Primary colonizing bacteria adhere to specific substrates, divide to form sister cells and the resultant microcolonies release soluble substrates which attract additional microorganisms to the digestion site. These newly attracted microorganisms associate with primary colonizers to form complex multi-species consortia. Within the consortia, microorganisms combine their metabolic activities to produce the diversity of enzymes required to digest complex substrates (e.g., cellulose, starch, protein) which comprise plant tissues. Feed characteristics that inhibit the microbial processes of penetration, colonization and consortia formation can have a profound effect on the rate and extent of feed digestion in the rumen. Strategies such as feed processing or plant breeding which are aimed at manipulating feed digestion must be based on an understanding of these basic microbial processes and their concerted roles in feed digestion in the rumen.

The Low Feed Intake in Newly-weaned Pigs: Problems and Possible Solutions

  • Dong, G.Z.;Pluske, J.R.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.3
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    • pp.440-452
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    • 2007
  • The low feed intake immediately after weaning is responsible for villous atrophy and reduced growth rate in newly-weaned pigs. Overcoming this drawback will produce beneficial results for swine producers, and this warrants an understanding of the factors affecting the feed intake in newly-weaned pigs. In fact, a plethora of factors exert influences on feed intake in newly-weaned pigs, and these factors encompass health status, creep feeding, weaning age, mixing of litters, environment, dietary nutrient level and balance, palatability of ingredients, forms of diet presentation, water supply and quality, and stockmanship. Due to the complexity of the factors that affect the feed intake of weaned pigs, a comprehensive approach should be adopted to overcome the low feed intake problem right after weaning. It warrants mention that it is almost impossible to completely restore the feed intake just after weaning to pre-weaning level in terms of energy intake through dietary means which are available for being practiced economically and/or technically in current swine production. However, a refined dietary regime will certainly alleviate the low feed intake problem in the immediate postweaning period.

Dietary inclusion effect of various levels of jack mackerel meal on the growth performance, feed efficiency and whole body composition of rockfish (Sebastes schlegeli)

  • Baek, Seong Il;Cho, Sung Hwoan;Kim, Hee Sung
    • Fisheries and Aquatic Sciences
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    • v.24 no.9
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    • pp.311-317
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    • 2021
  • Inclusion effect of various levels of jack mackerel meal (JMM) acting as feed attractants and/or stimulants in diets on the growth, feed consumption, feed utilization and whole body composition of rockfish was investigated. Three hundred juvenile rockfish were randomly allocated into 15 flow-through tanks. Five experimental diets supplemented with JMM at 0%, 1%, 3%, 5%, and 10% at the expense of anchovy meal were prepared and referred to as the JMM0, JMM1, JMM3, JMM5, and JMM10 diets, respectively. Weight gain, specific growth rate (SGR) and feed consumption of fish tended to improve with dietary levels of JMM. The greatest weight gain, SGR and feed consumption were observed in fish fed the JMM10 diet, followed by the JMM5, JMM3, JMM1, and JMM0 diets, in that order. Condition factor (CF) of fish tended to improve with dietary inclusion levels of JMM. Growth performance, feed consumption and CF of fish tended to improve with dietary inclusion levels of JMM ranging from 0% to 10%.

Feed Intake Evaluation of Korean Cattle (Hanwoo) Fed Diets Containing Different Levels of Compound Fattening Periods (한우의 육성 및 비육기간중 배합사료 급여 수준에 따른 사료섭취량 조사)

  • Shin, K.J.;Oh, Y.G.;Lee, S.S.;Kim, K.H.;Kim, C.H.;Paik, B.H.
    • Journal of Animal Science and Technology
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    • v.44 no.1
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    • pp.95-104
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    • 2002
  • A study was conducted to evaluate feed intake of Hanwoo bulls and steers fed diets of compound feed and rice straw. Twenty bull calves and sixty steers at 5 to 7 months old were used. The experimental period was divided into three feeding stages which are growing period (〈300 kg body weight (BW)), early fattening period (300-450 kg BW) and late fattening period (〉450 kg BW). The animals were given the diets containing 14.1% crude protein (CP) and 70.0% total digestible nutrients (TDN) in the growing period, 12.1% CP and 70.6% TDN in the early fattening period, and 11.2% CP and 71.9% TDN in the late fattening period, respectively. Experiment 1 was designed to compare feed intake (as-fed basis) between Hanwoo bulls and steers fed the experimental diets ad libitum. In Experiment 2, Hanwoo steers were allocated in one of three compound feed feeding treatments to investigate feed intake (as-fed basis). The treatment groups were ① feeding level 1 group fed compound feed ad libitum through the whole periods; ② feeding level 2 group fed 1.0% compound feed per kg BW in the growing period, 1.5% compound feed per kg BW in the early fattening period and compound feed ad libitum in the late fattening period; and ③ feeding level 3 group fed 1.5% compound feed per kg BW in the growing period, 2.0% compound feed per kg BW in the early fattening period and compound feed ad libitum in the late fattening period. In Experiment 1, the average daily feed intake of bulls increased linearly through the whole experimental period while the feed intake of steers increased until their body weight was reached upto 521 kg, afterward reduced. Average daily feed intake was about 3.5% per kg BW of both bulls and steers at the beginning (150 kg BW) of Experiment 1 while bulls and steers at 600 kg BW consumed the diets of 2.0 and 1.5% per kg BW, respectively. In Experiment 2, the average daily feed intake of steers in the feeding level 1 group gradually increased through the growing and early fattening periods and then steadily reduced over the late fattening period. The average daily feed intake in the feeding level 2 group linearly increased through the whole period while the feed intake in the feeding level 3 group showed a relatively rapid increase and reached a peak at 455 kg BW, and then sharply dropped. The average daily feed intake of steers in the feeding level 1 at the beginning (150 kg BW) of Experiment 2 was about 3.5% per kg BW but there was a reduction (1.5% per kg BW) at 600 kg BW. Besides, The feed intake of steers in the feeding level 2 and 3 in which compound feed was given with limitation increased to 2.0-3.0% per kg BW in the growing period and then reduced to 1.5-2.0% per kg BW. The limited compound feed feeding of steers in Experiment 2 resulted in higher rice straw intakes up to two to three folds and two folds in the growing and early fattening periods, respectively, than the ad libitum feeding.

A Method of White Noise Reduction for Recognizing Cattle's Gulp Downing Sounds

  • Kwak, Ho-Young;Kim, Woo-Chan;Chang, Jin-Wook
    • Journal of the Korea Society of Computer and Information
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    • v.24 no.11
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    • pp.153-161
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    • 2019
  • In this paper, we proposed a method to measure the feed intake of cattle using the cattle's gulp downing sounds. To measure the sound of cattle's gulp downing, the recording is performed through a wearable device attached to the cattle's neck. A lot of noises are recorded according to the ranching environment. This paper proposed a method for spectralizing raw gulping sound data containing white noise and removing white noise through the signal transformation using a filter. This allows the feed intake to be measured. Through the proposed white noise reduction method, it was possible to extract only the cattle's gulp downing sound, and through this, the number of cattle's gulp downing could be measured. The proposed method in this paper makes it possible to measure cattle's feed intake easily, so that estrus prediction, health care for cattle, and feed management can be done efficiently.

DIVERGENT SELECTION FOR POSTWEANING FEED CONVERSION IN ANGUS BEEF CATTLE VI. REALIZED HERITABILITY ESTIMATES

  • Park, N.H.;Bishop, M.D.;Davis, M.E.
    • Asian-Australasian Journal of Animal Sciences
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    • v.7 no.4
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    • pp.475-479
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    • 1994
  • Postweaning performance data were obtained on 401 group fed purebred Angus calves from 24 selected sires (12 high and 12 low feed conversion sires) from 1983 through 1986 at the Northwestern Branch of the Ohio Agricultural Research and Development Center. A single generation divergent selection experiment was replicated four times (1983, 1984, 1985 and 1986) to obtain an realized heritability estimate for postweaning feed conversion. The 140-d postweaning period was divided into five 28-d periods. Realized heritability estimates for feed conversion by 28-d periods fluctuated greatly and demonstrated no particular pattern. Heritability was highest for the fourth period (between d 85 and 112 of postweaning period, 0.61). Thus, beef producers could successfully select for feed conversion.

Mechanism Analysis and Optimal Desing of feeding Mechanism of Industrial 2 needle Sewing Mechine (공업용 2본침 침송 재봉기의 이송 메카니즘 해석 및 최적설계)

  • 이장용;전경진
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.04a
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    • pp.803-807
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    • 1996
  • In this paper, we perform a mechanism anlysis and optyimal designof the feeding system in a industrial sewing machine. Sewing machines are classified by the transfer mechanism as (1) transferred by feed dog only (2) transferred by feed dog and needle (3) transferred by feed dog, needle and pressure bar. We took the dewing machine classified as (2) which is more efficient in transferring the clothes than the machine classified as (1). In analyzing the mechanism, we divide the feeding mechanism as feed dog mechanism and needle bar mechanism. The two mechanisms are connected with each other kinematically because the clothes are transferred by needle and feed dog simultaneously and stitched by needle which pass through the feed dog in every stitchcycle. We define good stitch as coincidence of stitch between the forward and reverse motion of feeding. And we optimize feeding mechanism for that purpose. It is illustrated that stitching performance of the optimized mechanism is compared to original feeding mechanism.

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Influence of Working Conditions on the Spinnability of Cylindrical Cups of Aluminum Sheet Metal (알루미늄 원통컵의 스피닝 성형성에 영향미치는 작업조건 연구)

  • 김종호;박규호;나경환;김승수
    • Transactions of Materials Processing
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    • v.8 no.5
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    • pp.465-470
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    • 1999
  • Many researchers have, nowadays, studied on spinning which can produce highly qualified products by CNC spinning machine equipped with hydraulic devices. The products have continuous metal flow which improves fatigue life, yield point, tensile strength and hardness. This study is to investigate the influence of various working conditions on the spinnability of cylindrical cups such as feed rate(ν), feed pitch(p), angle of roller holder(α), and the inclination angle of first roller path. Through experiments the feed rate of (0.4∼0.7) mm/rev was shown to give the drawing ratio of 2.5 when the angle of roller holder was 5°, However, by increasing the angle of roller holder from 5°to 20°, the range of feed rate which can produce deeper cups became wider and the spinnability was also improved. The optimum working conditions, for the maximum formability of aluminum sheet metal as well as dimensional accuracy of spun cups, are presented and discussed.

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