• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.2
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• pp.116-116
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• 1999

In this study we propose a novel approach with which design engineers can define and design free-from surface more easily. Free-from surface is defined as a parameterics shape which consists of a set of contr ol points. Parametric shape which not only has the advantage of allowing users to perform design changes efficiently, but also provides designers with a natural design environment in which they can do their work more naturally and creatively. The objective of this study is to develop a PC level freeform surface modelling system which explicitly represents information of part geometry. In this study, freeform surface modeling system consist of three modules : freeform surface modeler, input/output modules and interface with Database. In recent year there are increasing demands for the 5-axis machining of a complicated shape. This study is the development of a CAM software system (or NC module) for the 5-axis machining of a general shape with a flat-end mill, a round-end mill, a ball-end mill.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.4
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• pp.573-578
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• 2013

A total of 720 1-d-old male broilers (Arbor Acres) with the initial BW = $45{\pm}2$ g were used in a 32-d experiment. Birds were randomly allotted into 1 of 4 treatments according to a completely random block design. Dietary treatments included: i) CON (basal diet), ii) ANT (CON+0.5 g antibiotics/kg feed (bacitracin methylene disalicylate)), iii) BP1 (CON+0.25 bacteriophage/kg feed), and iv) BP2 (CON+0.5 g bacteriophage/kg feed). The BWG and FI were not affected by dietary treatments throughout the whole experiment, whereas BP2 treatment reduced (p<0.05) the feed conversion ratio compared with the CON treatment during 0 to 14 d. The birds fed bacteriophages at the level of 0.25 g/kg increased (p<0.05) the relative liver weight. The inclusion of antibiotic and bacteriophage significantly reduced (p<0.05) the Escherichia coli and Salmonella concentration in the excreta compared with the NC group. Broilers fed the BP2 treatment had higher (p<0.05) lactobacillus counts compared with those fed NC and PC treatments. In conclusion, dietary supplementation of 0.5 g/kg bacteriophages increased feed efficiency and liver weight without effects on the breast muscle properties; also pathogens were inhibited by addition of bacteriophages.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1991.04a
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• pp.284-289
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• 1991

3차원 자유곡면을 볼엔드밀을 사용하여 금형가공을 할 경우, 가공면에는 공구경로에 따른 흔적과 NC공작기계의 직선보간시 발생되는 가공오차에 의하여 공작물 상에 가공오차가 필연적으로 발생되게 된다. 따라서 공작기계상에 서 금형가공을 수행한 후에는 가공오차를 제거하고 금형의 표면을 매끄럽게 하기위하여 연마작업이 픽수적으로 요구 되고있다. 본 연구에서는 3차원 자유곡면으로 이루어진 금형의 연마가공에 로봇을 도입하고, 이를 위한 로봇 작업단의 경로 제어시비전문가라 할지라도 CAM시스템으로 부터 금형 가공용 NC공작기계의 공구경로데이타(Cutter Location Data)를 받으면 자유곡면을 모형화한 후 자유곡면의 법선벡터와 연마로봇 작업단의 위치벡터를 자동으로 생성하고, 그에 따른 로봇의 작업명령을 자동으로 생성할 수 있는 CAMPoli 오프라인 로봇 프로그래밍 시스템을 개발하였다. CAMPoli시스템은 마이크로소프트사의 WINDOWS/386 오퍼레이팅 시스템을 이용하여 IBM-PC/386 상에서 개발되었으며 그주요한 내용들은 다음과 같다. i) CAM시스템으로 부터 입력된 CL-데이타로부터 연마면에 대한 자유곡면을 생성하고, ii) 연마공정의 데이타베이스에 기초한 연마면수의 지정 및 변경을 수행하고, iii) 자유곡면 연마를 위한 로봇 작업단의 위치벡터와 법선벡터를 계산하고, iv) 기존의 로봇언어를 이용한 오프라인 소스프로그램(Source Program)을 생성 및 그래픽 시뮬레이션 하는 과정으로 구축되었다.

• IE interfaces
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• v.11 no.2
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• pp.65-78
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• 1998

The letters of the automobile tire are usually engraved on the side-wall. The shape of the side-wall is a sculptured surface generated by the rotational sweeping of a profile curve. The letters laid on the side-wall are usually designed by a 2-dimensional CAD. It is impossible to machine the letters on the surface accurately by 3-axis NC machining, because the axis of cutter should be tilted to align with the normal vector of the surface. In this case. the degree of freedom for the machine is at least four. This paper describes an idea for tool path generation of a 4-axis machine by using the 2-dimensional CAD data of the letters and the surface of the side-wall. This study includes the following procedures; (1) measuring the profile of the side-wall surface and curve-fitting of the measured points. (2) the 'non-parallel projection' of the letters on the side-wall, and (3) an inverse kinematics of the 4-axis lettering machine. Procedures in this paper are programmed in C-language on Windows95 environment. With a PC based CNC controller and a 4-axis lettering machine. these are tested sucessfully for the practical use.

• Journal of Animal Environmental Science
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• v.22 no.1
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• pp.27-34
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• 2016

The objective of this study was to increased breeding area in same size pig pen and growth performance of weaning pigs. A total of 330 crossbred ($6.68{\pm}0.36kg$) weaning pigs were subjected to a 42-day feeding trial(3 pens/treatment) in which effects of the semi-floor were compared : NC; Negative control ($0.23m^2/pig$; 40 pigs/pen), PC; Positive control($0.30m^2/pig$; 30 pigs/pen) and Semi-floor($0.30m^2/pig$; 40 pigs/pen). There was a significant effect on BW at 6 week along all treatment(P<0.01). There was a effect of Semi-floor treatment on ADG(average daily gain) only during the first 3 week after weaning(P<0.01). No significant effect was observed in the ADFI during the experiment period. NC treatment had significantly lower BUN value than other treatments(P<0.05). The results from immune and stress response with semi-floor suggest that no negative effects in their blood analysis. Consequently, semi floor treatments increased additional breeding area and also growth performance rather than other treatments in weaning pigs.

• Journal of Animal Science and Technology
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• v.52 no.2
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• pp.125-130
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• 2010

This study was conducted to investigate the effects of blended feeding essential oils on meat quality improvement for branded pork. A total of one-hundred pigs ($66.24\;{\pm}\;0.83\;kg$, average initial BW) were used for 10 weeks study. Dietary treatments included: 1) CON (basal diet), 2) NBE (basal diet + 75 ppm of blended essential oil), 3) NBA (basal diet + 0.3% Benzoic acid) and 4) BEB [basal diet + 75 ppm of blended essential oil (with 0.3% Benzoic acid)]. The marbling value was improved in NBE treatment compared to NC and PC treatments (P<0.05). Hardness was higher in NBA treatment than NC and PC treatments (P<0.05). The pH value was higher in BEB treatment than PC and NBE treatments (P<0.05). In fatty acid content of lean, total UFA/SFA was higher in NBA treatment than BEB treatment (P<0.05). In conclusion, the results of this study indicated that dietary supplementation with blended essential oils improve fatty acid content of meat.

• Biomedical Science Letters
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• v.16 no.1
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• pp.68-70
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• 2010

Puer tea is a traditional beverage originating from Yunnam area of China. It supplies basic nutrients such as vitamin C. It has been well reported that daily drinking of Puer tea can help the digestion and ease the stomachache after food intake. Puer tea also contains various polyphenols which may exert antibacterial activity against Staphylococcus aureus and Listeria monocytogenes. Because of these functional effects on digestive system we suspected if Puer tea can display any dietary effect or decrease the obesity after long-term drinking. We employed 6-week old SD rats as experimental animal and treated them with extract of Puer tea in relation to the body weights. Rats were divided into 5 groups (NC, PC, E, E+P, E+P5). NC group was experimental control and rest of them are as follows: water only (PC), water with exercise (E), water with exercise and Puer tea extract (E+P), water with exercise and 5X extract of Puer tea (E+P5). Feeding was carried out every day for 5 weeks by oral administration. Reduction rate of body weights was highest in E group. Relative ratio of losing weight was as follows: PC group (100.78%), E group (95.57%), E+P group (94.53%) and E+P5 group (74.22%), respectively. Exercise was more helpful to control the body weight. The result strongly suggests that Puer tea is highly effective to control the body weight and could be used for pharmaceutical purpose to treat obesity without side effects.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.30.2-31
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• 2017

Compact elliptical (cE) galaxies are in a rare class of stellar systems characterized by high stellar densities, small sizes, high velocity dispersion, and high metallicity corresponding to elliptical galaxies. cE galaxies have been observed around massive galaxies, so they could be formed under strong influences of tidal stripping and truncation. However, the recent discovery of isolated cE galaxies requires the need of new formation scenarios. We aim at finding cE galaxies in various environments using SDSS DR12, and studying stellar population of cEs as function of environments. Based on the typical properties of cE galaxies, we selected cE candidates by restricting that low-luminosity Mg > 19.5 mag, small sizes Re < 700 pc, and high velocity dispersions ${\sigma}$ > $60kms^{-1}$. Since effect radii of cE candidates are mostly smaller than the seeing size of SDSS photometry, we calculated the effective radius by fitting a Sersic profile. In addition, we assumed that host galaxies have brightness with Mr < -21 mag, and an environmental parameter is computed as distances between cE galaxies and host-galaxies. We found 112 cE galaxies at z < 0.05, which have high sersic indices (mean value is 5.2) similar to the typical massive elliptical galaxies. Mgb values of cE galaxies increase as the distances from the host galaxies decrease. Especially, for cEs close to the host galaxies (NcE; $D_{host}$ < 300 pc), the Mgb values are similar to those of massive elliptical galaxies, which is consistent with the previous studies. On the other hand, cE galaxies distant from the host galaxies (DcE; Dhost >300 pc) have lower Mgb values than the conventional cE. The Mgb values follow the ${\sigma}$-Mgb relation of elliptical galaxies, and are connected to its faint end. This can be explained as a result of different merger histories for differing environments. For example, NcE galaxies are formed by tidal stripping by massive galaxies as suggested by previous studies, but DcE galaxies could be linked with high-redshift spheroids (e.g. red nuggets) which have not evolved into present-day elliptical galaxies because of the environmental influences.

• Korean Journal of Poultry Science
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• v.39 no.1
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• pp.63-70
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• 2012

This study was conducted to determine the possible use of Red Ginseng marc as stress inhibiter in thermal stress (temperature humidity index 86) and lipopolysaccharide (LPS) - exposed laying hens by investigating their effects on laying performance, blood biochemical parameters, immunoglobulin concentration and serum superoxide dismutase (SOD) like ability. A total of forty-five 52-wk-old laying hens (ISA Brown) were divided into 3 treatment groups with 5 replicates of 3 birds in each group. NC (negative control, no immune substances), PC (positive control, ${\beta}$-glucan 25 ppm) and RGM (Red Ginseng Marc 3%) were added in feed with respective substance. Egg production in RGM was significantly increased in comparison with NC groups for 8 weeks (P<0.05). On blood biochemical parameters, effects of ambient temperature is definite by showing significant difference in aspartate aminotransferase and others (P<0.05), but RGM both before and after thermal stimulation have no significant difference in comparison with other groups. And for 3 weeks after thermal stimulation, laying performance was also not significantly different among treatments. Immunoglobulin M content and SOD like activities after challenge with LPS were higher in the RGM and PC than NC (P<0.05). In conclusion, although ineffective as inhibiter in thermal stress, dietary supplementation of Red Ginseng marc improved SOD like activity and immune system by regulating immunoglobulin content in laying hens. These findings have laid the foundation for future studies of immunomodulation in laying hens fed Red Ginseng Marc and of evaluation of heat stress inhibitor.

• Korean Journal of Poultry Science
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• v.44 no.2
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• pp.113-122
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• 2017

This study was conducted to investigate the effect of dietary supplementation with Lactobacillus, medicinal plant extracts, and plant extracts on growth performance, cecal microflora, relative organ weight, and lymphocyte profile in broiler chickens. One hundred broilers (5 wk old) were used and divided into five (treatment) ${\times}$ two (challenged Salmonella) groups containing 10 broilers. The treatments were as follows: no antibiotics group (NC), antibiotics group (PC), 0.1% lactic acid bacteria group (LB), 100 ppm medicinal plant extract group (MPE), and 100 ppm herb extract group (HE). A basal diet was formulated as 3,100 kcal/kg ME and 20% CP based on corn and soybean meal. Broilers were fed with the experimental diets with no challenge for 1 wk and with challenge of SG for 2 wk. SG were added in water as $1.0{\times}10^6cfu/L$. Final body weight and weight gain were significantly decreased following challenge with SG (P<0.05). However, with the addition of antibiotic alternatives, growth performance was improved and reduction of performance following challenge with SG was lowed compared with that of the NC treatment (P<0.05). Coliform bacteria and Salmonella but not lactic acid bacteria increased with the addition of antibiotic alternatives (P<0.05). Lactobacillus increased significantly with the addition of lactic acid bacteria compared with the NC and PC treatments (P<0.05). The weight of liver, spleen, and bursa of Fabricius increased with addition of antibiotic alternatives (P<0.05). WBC was highly reduced at 4 days after challenge with SG, but was normally maintained thereafter. There was no significant difference in coliform bacteria, Salmonella, organ weights, or WBC with the addition of antibiotic alternatives. Finally, Lactobacillus, medicinal plant extract, and herb extract can be used as antibiotic alternatives; but one alternative completely can't alternate as antibiotics. Therefore, further studies are needed to investigate the synergistic effects of two or more antibiotic alternatives.