• Title/Summary/Keyword: feed rate

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Effects of Dietary Animal Feed on the Growth Performance of Edible Insects (가축사료를 첨가한 먹이원의 급여가 부식성 식용곤충의 생육에 미치는 영향)

  • Song, Myung-Ha;Lee, Heui-Sam;Park, Kwanho
    • Journal of Life Science
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    • v.28 no.5
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    • pp.563-568
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    • 2018
  • The insect industry is a promising agricultural resource and expected to grow steadily. In Korea, Gryllus bimaculatus and the larvae of Tenebrio molior, Protaetia brevitarsis, and Allomyrina dichotoma were listed as general food ingredients. As interest in these edible insects increases, rearing techniques and nutritious food sources are needed for mass production. In this study, wheat bran, dog feed, and pig feed were investigated for their effects on the larval growth of P. brevitarsis and A. dichotoma. When fermented sawdust with 30% wheat bran was used, the larval survival rate of P. brevitarsis and A. dichotoma (p=0.244341 and p=0.007966, respectively) and growth rate (p=0.001400 and p=0.000051, respectively) were significantly lower than those of the control (fermented sawdust with no supplement). Therefore, fermented sawdust with a high density of wheat bran was inappropriate for both insects. When fed fermented sawdust with 2.5 or 5% of dog and pig feed, the survival rate and growth rate of the larvae were higher than those of the control. Interestingly, the maximum larval weight with 2.5% dog feed was increased by $3.35{\pm}0.10g$ and $32.59{\pm}0.79g$ for P. brevitarsis and A. dichotoma, respectively. In addition, the larval period of both was shorter than that of the control by 40 days or more. Therefore, it is considered that animal feed can be used as a feed source for these edible insects.

Effects of Stocking Density on the Blind-side Hypermelanosis of Cultured Olive Flounder Paralichthys olivaceus

  • Kang, Duk-Young;Kim, Hyo-Chan;Chang, Young-Jin
    • Fisheries and Aquatic Sciences
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    • v.14 no.2
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    • pp.123-129
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    • 2011
  • To determine whether rearing density affects the hypermelanosis on the blind side (ambicoloration) of olive flounders Paralichthys olivaceus, we reared fry with an unpigmented non-eyed (blind) side in duplicate at densities of 150 individuals/$m^2$ (commercial production density: control) and 450 individuals/$m^2$ (high density group) for 90 days in 1-t dark-green fiberglass reinforced plastics (FRP) tank. We recorded feed intake, feed conversion efficiency (FE), growth and survival, and measured the ratios of staining blind-side area (staining area) and ambicolored fish every 30 days. Daily feed intake (DFI), feed conversion efficiency (FE), growth rate, condition factors, and survival rate were calculated at the end of the experiment. Although the FE was higher in the high-density compared to the control, the two density groups showed similar feed intakes, growth, and survival. The ratio of staining area as well as the ratio of ambicolored fish significantly were significantly higher in the high-density group than in the control from days 30 to 60, but significantly increased and evened out by the end of the experiment (P<0.05). In conclusion, we determined that rearing density is not the main cause of the blind-side hypermelanosis, but found that increasing the rearing density can accelerate the ambicoloration in olive flounders.

Predicting Feed Intake of Fallow Deer (Dama Dama) Using Alkanes as a Marker

  • Ru, Y.J.;Miao, Z.H.;Glatz, P.C.;Choct, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.2
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    • pp.209-212
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    • 2002
  • The understanding of seasonal forage intake of grazing deer is essential for the development of supplementary feeding strategies in southern Australia. The alkane technique is used in other animal species for estimating feed intake of individual animals and their diet composition. To assess the potential of using alkanes as a marker for predicting feed intake of fallow deer, the daily faecal recovery of alkanes and excretion rate of dosed artificial alkanes (C32 and C36) were measured with 6 deer fed three forage based diets. The artificial alkane capsule designed for use in sheep is suitable for fallow deer. Faecal samples need to be collected over days 7-19 after dosing. The daily excretion rate was 40 mg for C32 and 37 mg for C36. The faecal recovery of natural alkanes is incomplete and the faecal concentrations of alkanes need to be adjusted for an accurate estimation of intake. The actual feed intake of 6 experimental deer over a 5 day period was accurately estimated ($R^2$=0.52) using alkanes.

A Study on the Thermal Characteristics of Vacuum Membrane Distillation Module (VMD 모듈의 열성능 특성 연구)

  • Joo, Hong-Jin;Yang, Yong-Woo;Kwak, Hee-Youl
    • Journal of the Korean Solar Energy Society
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    • v.34 no.5
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    • pp.23-31
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    • 2014
  • This study was accomplished to get the foundation design data of VMD(Vacuum Membrane Distillation) system for Solar Thermal VMD plant. VMD experiment was designed to evaluate thermal performance of VMD using PVDF(polyvinylidene fluoride) hollow fiber hydrophobic membranes. The total membrane surface area in a VMD module is $5.3m^2$. Experimental equipments to evaluate VMD system consists of various parts such as VMD module, heat exchanger, heater, storage tank, pump, flow meter, micro filter. The experimental conditions to evaluate VMD module were salt concentration, temperature, flow rate of feed sea water. Salt concentration of feed water were used by aqueous NaCl solutions of 25g/l, 35g/l and 45g/l concentration. As a result, increase in permeate flux of VMD module is due to the increasing feed water temperature and feed water flow rate. Also, decrease in permeate flux of VMD module is due to increasing salinity of feed water. VMD module required about 590 kWh/day of heating energy to produce $1m^3/day$ of fresh water.

Performance of Flow Rate Control of a Cavitating Venturi (캐비테이션 벤튜리의 유량제어 성능)

  • Cho Won Kook;Moon Yoon Wan;Kim Young-Mog
    • 한국전산유체공학회:학술대회논문집
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    • 2002.05a
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    • pp.146-151
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    • 2002
  • Characteristics of flow rate control has been studied for a cavitating venturi adopted in a liquid rocket propellant feed system. Numerical simulation has been peformed to give about $10\%$ discrepancy of mass flow rate to the experimental data for cavitating flow regime. Mass flow rate is confirmed to be saturated for pressure difference higher than $3\times10^5$pa when the upstream pressure is fixed to $22.8\times10^5$pa and the downstream pressure is varied. The evaporation amount depends substantially to non-condensable gas concentration. However the mass flow rate characteristic is relatively insensitive to the mass fraction of non-condensable gas. So it is reduced by only $2\%$ when the non- condensable gas concentration is increased from 1.5PPM to 150PPM. From the previous comparison the expansions of the non-condensable gas and the evaporation of liquid are verified to have same effect to pressure recovery.

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A Study on Feed Rate Characteristics of Motor-driven Cylinder Lubricator by the Electronically Controlled Quill System Equipped with an Accumulating Distributor in a Large Two-stroke Diesel Engine (대형 2행정 디젤기관에 있어서 축압분배기 부착 전자제어식 퀼 시스템 모터구동 실린더 주유기의 송출유량 특성에 관한 연구)

  • Bae, Myung-Whan;Jung, Hwa;Bae, Chang-Hwan
    • Transactions of the Korean Society of Automotive Engineers
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    • v.19 no.4
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    • pp.91-98
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    • 2011
  • Minimizing the cylinder wear and the consumption rate of cylinder oil in a large two-stroke diesel engine is of great economic importance. A motor-driven cylinder lubricator for Sulzer RT-flex large two-stroke diesel engines developed by authors is in need of mounting a quill system to lubricate cylinder parts for smoother operation. In order to apply the common-rail lubricating system to the developed cylinder lubricator as the second research stage, the quill system with a progressively quantitative distributor is improved in the electronically controlled quill system with an accumulating distributor. In this study, the effects of lubricator motor speed, plunger stroke and cylinder back pressure on oil feed rate, maximum discharge and delivery pressures are experimentally investigated by using the electronically controlled quill system with an accumulating distributor in the developed cylinder lubricator. It is found that the oil feed rate of the electronically controlled quill system with an accumulating distributor is larger than that of the quill system with a progressively quantitative distributor because of the increase of delivery speed and volume by changing the location of accumulator in the same experimental condition.

A Study on Feed Rate Characteristics of Integrated Cylinder Lubricator System with an Accumulated Distribution by the Electronic Control in a Large Two-stroke Diesel Engine (대형 2행정 디젤기관에 있어서 일체형 전자제어 축압분배 실린더 주유기 시스템의 송출유량 특성에 관한 연구)

  • Bae, Myung-Whan;Jung, Hwa;Bae, Chang-Hwan
    • Transactions of the Korean Society of Automotive Engineers
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    • v.20 no.6
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    • pp.52-60
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    • 2012
  • Minimizing the cylinder wear and the consumption rate of cylinder oil in a large two-stroke diesel engine is of great economic importance. A motor-driven cylinder lubricator for Sulzer RT-flex large two-stroke diesel engines developed by authors is in need of modifying the lubricating system to lubricate cylinder parts optimally by an electronically controlled quill device according to changes of engine load and revolution speed. In order to apply the developed accumulating distributor to an integrated cylinder lubricator by the electronically controlled system as the third research stage, the lubricating system is improved in the electronically controlled quill device with a solenoid valve. In this study, the effects of lubricator revolution speed, driving pressure and cylinder back pressure on oil feed rate, maximum discharge and delivery pressures are experimentally investigated by using the integrated cylinder lubricator system with an accumulated distribution by the electronic control. It is found that the oil feed rate of the developed integral cylinder lubricator system is less than that of the motor-driven cylinder lubricator by the electronically controlled quill system equipped with an accumulating distributor because of the decrease of delivery speed by increasing the maximum delivery pressure in the same experimental condition.

A Study on Effect of Quill Accumulator upon Performance of Motor-driven Cylinder Lubricator in a Large Two-stroke Diesel Engine (대형 2행정 디젤기관용 모터구동 실린더 주유기의 성능에 미치는 퀼 어큐뮬레이터의 영향에 관한 연구)

  • Bae, Myung-Whan;Ok, Hyun-Jin;Jung, Hwa
    • Transactions of the Korean Society of Automotive Engineers
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    • v.15 no.2
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    • pp.115-125
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    • 2007
  • Minimizing the cylinder wear and the consumption rate of cylinder oil in a large two-stroke marine diesel engine is of great economic importance. In Korea, a motor-driven cylinder lubricator for a large two-stroke marine diesel engine manufactured by $W{\ddot{a}}rtsil{\ddot{a}}$ Switzerland Co., Ltd. was first developed by authors through the joint research of industry-university in 2002. The characteristic of the developed product is that can control automatically the oil feed rate to a load fluctuation by the motor drive and the offset cam. The performance of the product is not also inferior to the conventional one. For manufacturing the reliable and useful products, however, it is necessary to investigate further characteristics and improve the performance of a cylinder lubricator. In this study, the effect of quill with and without accumulator on maximum discharge pressure, delivery delay duration and oil feed rate relative to motor revolution speed using plunger stroke as a parameter is experimentally investigated by using the developed cylinder lubricator. It is found that the maximum discharge pressure with accumulator is higher than that of no accumulator as plunger stroke and motor revolution speed are elevated, and the delivery delay duration with accumulator is shorter than that of no accumulator as plunger stroke and motor revolution speed are increased. Also, oil feed rate with accumulator is less than that of no accumulator except for a plunger stroke of 2 mm as plunger stroke and motor revolution speed are raised.

The Effects of Inhalation of Essential Oils on the Body Weight, Food Efficiency Rate and Serum Leptin of Growing SD Rats (향흡입이 성장하는 쥐의 체중, 섭취효율 및 혈청 렙틴에 미치는 효과)

  • Hur, Myung-Haeng;Kim, Chan;Kim, Chul-Hyun;Ahn, Hae-Chul;Ahn, Hye-Young
    • Journal of Korean Academy of Nursing
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    • v.36 no.2
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    • pp.236-243
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    • 2006
  • Purposes: This experimental study was designed to verify the effect of inhalation of essential oils on body weight, feed intake, food efficiency rate and serum leptin. Methods: The subjects of this study were 90 growing SD rats(46 males and 44 females). They were allocated into one of four groups, the Fennel group, Patchouli group, Bergamot group and control group. The experimental treatment was the inhalation of aromatherapy essential oils which was applied two times a day for 10 minutes each during 8 weeks. To evaluate the effects, body weight, feed intake, food efficiency rate and serum leptin were measured before and after the treatment. The collected data was analyzed by repeated measures of Kolmogorov-smirnov test and Normal Q-Q plot for nomality, Kruskal Wallis test and $X^2-test$ for experimental effects with the SPSS program. Results: The food efficiency rate was significantly lower in the Patchouli group and Fennel group than in the Bergamot group and control group(P=.000). No significant group effects were found for SD rat's body weight, feeding amount and serum leptin. Conclusion: In conclusion, these findings indicate that the inhalation of essential oils could be effective in lowering the food efficiency rate rather than the feed intake.

A Study on Effect of Cylinder Back Pressure on Feed Rate and Delivery Characteristics of Motor-driven Lubricator in a Large Two-stroke Diesel Engine (대형 2행정 디젤기관의 모터구동 주유기 유량 및 송출 특성에 미치는 실린더 배압의 영향에 관한 연구)

  • Bae Myung-whan;Jung Hwa;Ok Hyun-jin
    • Transactions of the Korean Society of Automotive Engineers
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    • v.13 no.5
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    • pp.19-28
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    • 2005
  • It is of great economic importance to minimize the cylinder wear and the consumption rate of cylinder oil in a large two-stroke diesel engine. The motor-driven cylinder lubricator was first developed fur a large two-stroke marine diesel engine made in $W{\ddot{a}}rtsil{\ddot{a}}a$ Switzerland Ltd. by the joint research of industry-university. In this study, the effects of revolution speed, plunger stroke and cylinder back pressure on maximum discharge and delivery pressures, delivery delay duration, and oil feed rate are experimentally investigated by the home-manufactured cylinder lubricator. The maximum discharge pressure with a spot of 0.03 m and the maximum loss pressure at spots of 5, 6.78 and i 0 m away from the end of lubricator slot are increased as plunger stroke, revolution speed and back pressure are elevated, and the delivery delay duration is shortened as plunger stroke, revolution speed and oil pipe length are increased. Also, oil feed rate is increased as plunger stroke and revolution speed are raised, but lowered as the back pressure is increased.