• Proceedings of the KSME Conference
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• 2002.08a
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• pp.385-388
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• 2002

The researches of a two-phase atomizers have been carried out in the field of automotive and aerospace industries in order to improve the atomization performance of the liquid droplets ejecting from these nozzles. The smaller droplets have the advantages of the reduction of environmental pollution matter and effective use of energy through the improvement of heat and mass transfer efficiency. Thus, to propose the basic information of two-phase flow, an internal mixing atomizer was designed, its shape factor was 0.6 and the liquid feeding hole was positioned at the center of the mixing tube which was used to mix the air and liquid. The experimental work was performed in the field after the nozzle exit orifice. The measurement of the liquid droplets was made by PDPA system. This system can measure the velocity and size of the droplets simultaneously. The number of the droplets used in this calculation was set to 10,000. The flow patterns were regulated by ALR (Air to Liquid mass Ratio). ALR was varied from 0.1024 to 0.3238 depending on the mass flow rate of the air. The analysis of sampling data was mainly focused on the spray characteristics such as flow characteristics distributions, half-width of spray, RMS, and turbulent kinetic energy with ALR.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.5
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• pp.681-685
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• 2000

A computer software was developed in our laboratory to automatically control the pigs environment by the image analysis system (IAS), which monitors and analyzes the pig's behavior and feeds the results back to the computer hardware. Three feeding trials were conducted with growing pigs ($L{\times}Y$) to test the effectiveness of the IAS under various seasons. In all three trials, the open-sided conventional pens with half-slatted floor were used as controls; for the IAS treatment, fully-slatted floors were used in the windowless pens. Experiment 1 was conducted in the winter for 30 d with 24 growing pigs. There were two treatments (Conventional vs. IAS), and three pens (replicates) per treatment. During the growing period, the feed efficiency was significantly (p<0.05) improved by the IAS. In addition, the pigs reared under the IAS during the growing period displayed better growth rate during the finishing period than did the pigs reared under the conventional conditions. Experiment 2 was conducted in the summer for 30 d with 24 growing pigs. The experimental design was the same as Experiment 1. During the finishing period, all the pigs were kept in conventional open-sided pens until their market weights to evaluate their carcass characteristics. During the growing period, the growth rate and feed efficiency of the pigs in the IAS was better than those of the control pigs. In addition, various carcass characteristics were significantly improved by the IAS rearing during the growing period. Experiment 3 was conducted with 30 growing pigs for 30 d in the spring. The experimental design was the same as Experiment 1. No difference was found in growing performance between the control and IAS pigs. It could be concluded that the IAS is effective in providing optimum conditions for the growing pigs in summer and winter seasons. In addition, providing an optimum environment during the growing period results in improved growth rate, feed efficiency, and carcass qualities for the finishing pigs.

• Korean journal of applied entomology
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• v.51 no.3
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• pp.255-263
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• 2012

High frequency sounds disrupt physiological processes, such as feeding behavior, development and immune responses of Spodoptera exigua. We analyzed high frequency sounds with respect to biochemical changes in S. exigua. High frequency sound (5,000 Hz, 95 dB) suppressed protein synthesis and secretion of midgut epithelium. It also significantly inhibited a digestive enzyme activity of phospholipase $A_2$. The gene expression of three different heat shock proteins and apolipophorin III was altered, particularly in midgut tissue in response to high frequency sound treatments. High frequency sound treatments significantly increased sugar and lipid levels in hemolymph plasma. These results suggest that high frequency sounds are a physiological stress that induces biochemical changes in S. exigua.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.4
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• pp.497-505
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• 2012

To determine the effects of Banggihwanggi-tang(BGHGT) on obesity, the obesity-related factors[gastrin, calcitonin gene related peptide(CGRP), serotonin, ghrelin, obestatin, glucagon-like peptide-1(GLP-1), insulin, orexin, leptin] were investigated in the stomach, pancreas, brain of mice by immunohistochemical(IHC) methods for 4 weeks. The change of body weight was more reduced in BGHGT administered group than that of control group. The IHC density of the gastrin and CGRP positive cells on pylorus was higher in BGHGT administered group than that of control group. The number of ghrelin immunoreactive cells on stomach was lower in BGHGT administered group than that of control group. The IHC of GLP-1 positive cells did not observe in the stomach of BGHGT administered groups. The IHC density of GLP-1 in the pancreas was lower in BGHGT administered group than that of control group. The IHC density of insulin positive cells in the pancreas was lower in BGHGT administered group than that of control group. The IHC density of orexin positive neurons in the diencephalon was slightly higher in BGHGT administered group than that of control group. The IHC density of NPY and leptin positive neurons was slightly higher in BGHGT administered group than that of control group. The IHC density of serotonin positive neurons was higher in BGHGT administered group than that of control group. Therefore, we conclude that BGHGT activates appetite inhibitor through appetite related enteroendocrine cells and neuropeptides in stomach, pancreas and brain, and this activation may also be responsible for the inhibition of feeding behavior.

• Biomolecules & Therapeutics
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• v.22 no.5
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• pp.453-459
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• 2014

Chronic mild stress (CMS) has been reported to induce an anhedonic-like state in mice that resembles some of the symptoms of human depression. In the present study, we used a chronic mild stress animal model of depression and anxiety to examine the responses of two strains of mice that have different behavioral responsiveness. An outbred ICR and an inbred C57BL/6 strain of mice were selected because they are widely used strains in behavioral tests. The results showed that the inbred C57BL/6 and outbred ICR mice were similarly responsive to CMS treatment in sucrose intake test (SIT) and open field test (OFT). However, the two strains showed quite different responses in forced swimming test (FST) and novelty-suppressed feeding (NSF) test after 3 weeks of CMS treatment. Only C57BL/6 mice displayed the depression- and anxiety-like behavioral effects in response to CMS treatment in FST and NSF test. Our results suggest that there are differences in responsiveness to CMS according to the different types of strain of mice and behavioral tests. Therefore, these results provide useful information for the selection of appropriate behavioral methods to test depression- and anxiety-like behaviors using CMS in ICR and C57BL/6 mice.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.1 no.2
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• pp.23-33
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• 1991

Mn - Zn Ferrite has the natural characteristics of incongruent melting and the zinc oxide evaporation while the crystal is being grown. As a result of these, it comes into existence to be a non-uniform distribution of cations along the crystal growth axis and also Pt particles are usually precipitated into the crystals in Bridgman method since the melt zone is maintained for a long time in the crucible. These have bad effects on the magnetic properties of ferrites. But, to overcome these faults and then acquire the better single crystals. new modified growth method was developed and the growth factors were investigated as following: melt height in the crucible, surface tension and density of melt, the behavior of melt at interface, the shapes of crucible and solid -liquid interface, powder feeding rate, and the crystal growing speed. In additon, when we analyzed the compositional fluctuations of grown crystals, they were supressed within 1.5 mol% $Fe_20_3$, 2 mol% MnO, ZnO respectively with comparing to initial composition of crystal and the microstructures of crystals on the(110) plane were observed by optical microscope through the chemical etching technique and the magnetic properties were determined.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.54-60
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• 2008

The atomization characteristics of the dual air supplying twin-fluid nozzle were investigated experimentally using PIV and PDA systems. The two-fluid nozzle is composed of three main parts: the feeding injector to supply fluid that is controlled by a PWM (pulse-width modulation) mode, the adaptor as a device with the ports for supplying the carrier and assist air and the main nozzle to produce the spray. The main nozzle has the swirl tip with four equally spaced tangential slots, which give the injecting fluid an angular momentum. The angle of the swirl tip varied with 0$^{\circ}$ 30$^{\circ}$, 60$^{\circ}$ and 90$^{\circ}$, and the ratios of carrier air to assist air and ALR(total air to liquid) were 0.55 and 1.23, respectively. The macroscopic behavior of the spray was investigated using PIV system, and the mean velocity, turbulent intensity and SMD distributions of the sprays were measured using PDA system. As the results, the mean axial velocity at the spray centerline decrease with the increase of the swirl angle. The turbulent intensities of the axial and radial velocity were increased with the increase of the swirl angle. The mean SMD (Sauter mean diameter) of the radial direction along the axial distance shows the lowest value at the swirl angle of 60$^{\circ}$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.5
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• pp.332-341
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• 1989

Stomach contents and microstructures in otolith of Chaenogobius laevis were analyzed for the determination of age, growth and food. By comparaing structural similarity in a series of growth increments from three samples collected in a two-week interval, daily deposition of growth increments in otolith can be validated. Growth in length as daily basis was well represented by Gompertz curve: $L= 5.73{\cdot}\;e^{15.06}(1-e^{-0.0015t})$ for the fish age of $46\~102$ days. Mean growth rate increased from 0.40 mm/day for the age of $50\~60$ days to 0.85 mm/day for the age of $80\~100$ days. Chasnobius laevis showed a carnivorous feeding behavior and its major food items were polychaetes, amphipods and copepods. Small individuals ($15\~30$ mm SL) preyed heavily on copepods as well as polychaetes. However, the portion of copepods in stomach contents was decreased with increasing fish siEe, and this decrease was compensated by an increased consumption of amphipods.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.4
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• pp.514-521
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• 2018

Objective: This experiment was conducted to investigate the effects of crude glycerin from waste vegetable oil (CGWVO) on performance, carcass traits, meat quality, and muscle chemical composition. Methods: Twenty-four crossbred (Thai Native${\times}$Anglo Nubian) uncastrated male goats ($16.8{\pm}0.46kg$ body weight [BW]) were assigned to a completely randomized design and subjected to four experimental diets containing 0%, 2%, 4%, and 6% of CGWVO (63.42% of glycerol and 47.78% of crude fat) on a dry matter (DM) basis. The diets were offered ad libitum as total mixed rations twice daily. The feed intake, feeding behavior, growth performance, carcass and meat traits, and muscle chemical composition were evaluated. Results: Based on this experiment, there were significant differences (p>0.05) among groups regarding DM intake, growth performance, and carcass traits where goats receiving 6% of CGWVO had lower daily DM intake, growth performance, and carcass traits than those fed on 0%, 2%, and 4% of CGWVO. There were no effects of CGWVO on carcass length, carcass width, Longissimus muscle (LM) area, Warner-Bratzler shear force, pH and color of LM at 45 min after slaughter, as well as on other carcass cut and muscle chemical composition. Conclusion: In conclusion, the addition of up to 4% of DM in the diets for crossbred finishing goats seems to be the most interesting strategy, since it promotes greatest animal performance. Moreover, this study was a suitable approach to exploit the use of biodiesel production from waste vegetable oil for goat production.

• Polymer(Korea)
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• v.28 no.2
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• pp.177-184
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• 2004

Polymer-clay nanocomposite containing the low amounts of clay shows improved physical, mechanical properties. In this study, allyl ester prepolymer was synthesised by reactions of the diallyl terephthalate monomers and the 1,3-butanediol monomers. Nanocomposites of allyl ester prepolymer and the two kinds of the organically layered silicate were prepared by using the intercalation method as well as the in-situ polymerization method using. By varying the amount of clay content, curing conditions, and feeding conditions. the nanocomposite was studied using X-ray diffraction. From XRD results, allyl ester-Cloisite 30 B nanocomposite made by the in-situ polymerization method shows better exfoliation behavior compared with the intercalation method. It can be said that the transesterification reaction between functional groups (-OH) of intercalant and monomers results in the increased gallery distance. Also mechanical and thermal properties indicate that the dispersity of clay is an important factor for improving physical properties of the nanocomposite.