• 한국공작기계학회논문집
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• 제12권3호
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• pp.17-24
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• 2003

One of the most important performance criteria related to the gain tuning of controller for CNC machining center is the contour error. This study analyzed circular error by the axis-matched and mismatched cases. To reduce ellipse and radius error, it is necessary to set the gain for each axis to be same bandwidth and high response. Based on the analysis in the frequency domain, we simulate feed system by mathematical model and then predict bandwidth of each axis. For analysis of structure vibration while the each axis is moving, we try the various of measuring method and position loop is improved by jerk limit.

• 한국정밀공학회지
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• 제15권12호
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• pp.48-54
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• 1998

In sewing, fabrics is fed by an elliptic motion of the feed dog. The feeding control mechanism controls an elliptic motion of the feed dog, finally, controls stitch spacings and feeding directions of fabrics. This study discusses the feeding control mechanism of an industrial lock stitch sewing machine, which is a good example to study a machine kinematics. This study makes mathematical expressions of machine's motion in the feeding control mechanism. Thus, the motions of this mechanism are characterized, which will be used for kinematic analysis of the feed dog later. Also, the above mathematical expressions may be a basis for the new design of the feeding control mechanism and may be applied to development of the similar feeding control mechanism of other type sewing machine.

• 한국생산제조학회지
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• 제21권5호
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• pp.755-760
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• 2012

In this study, three dimensional cutting force components and surface roughness appeared in high speed cutting by using tungsten carbide endmill tools implanted ion or not found mutual relations through several analysis of statistical dispersion. It is showed that cutting force(Fx) is affect with spindle speed and feed rate, cutting force(Fy) is affect with spindle speed and ion implantation time and cutting force(Fz) is affect with feed rate in interaction through the statistical method of ANOVA of cutting force and surface roughness, it is analyzed that it is affected of spindle speed and feed rate in surface roughness.

• 한국정밀공학회지
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• 제27권12호
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• pp.119-124
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• 2010

In this paper, thermal stabilization design of a new concept compact machining center has been investigated. A new concept machining center adopted a new X-axis as a NC rotary table. A New concept compact machining center is designed that spindle speed, feed rate and NC Rotary table speed are 12,000rpm, 60m/min and 110rpm each. The analysis is carried out by using FEM simulation Solidworks, CATIA and ANSYS. This paper is focused on the thermal deformation according to temperature distribution of a spindle system and feed drive system. Heat transfer analysis is performed according to heat source and atmosphere contact parts. As a result, this compact machining center is designed as a thermally stable structure.

• 한국정밀공학회지
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• 제29권5호
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• pp.510-515
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• 2012

Feed drive systems are used to position the machine tool components carrying the cutting tool and workpiece to the desired location. Hence, their positioning accuracy and speed determine the quality and productivity of machine tools. In this paper, technical trend of machine tools feed drive systems are analyzed by patent mapping. And this paper suggested future development direction of feed drive systems. The analysis is carried out by using problem solution map (PSM) for the applied patent during January 2000 and December 2009 in Korea, Japan, EU and U.S.A.

• Journal of Advanced Marine Engineering and Technology
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• 제33권5호
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• pp.729-737
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• 2009

This paper introduces the machine tools feed system, which can be optimized the control's performance through simulation and the adjustment of the mechanical components. One method simulates the frequency response of the speed-loop with the design value using the MATLAB application, so that all of the interpolation axis can be equal to the response bandwidth, resulting in a high accuracy rate. The other method sees the mechanical component being adjusted by analyzing the results of various experiments. Lastly, this client's program is able to change the parameters that are related to the FFD, as well as the parameters in the friction compensation of the OPEN-CNC.

• 한국식품위생안전성학회지
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• 제26권1호
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• pp.1-11
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• 2011

국내 유통사료 239점에 대하여 푸사리움 속 곰팡이독소 4종(NIV, DON, T-2, ZEN)에 대하여 오염도조사를 실시하였다. 일반적으로 곰팡이독소 정제에 많이 사용되는 면역친화 컬럼을 사용하지 않고 일반 SPE컬럼을 이용하였으며, HPLC/MS/MS로 동시 분석하였다. 각각의 성분 별로 77.42~111.20%의 회수율과 $0.3{\sim}2.0\;{\mu}g/l$의 양호한 정성한계(LOD)를 보였다. 분석 결과 사료 중에 조사대상 곰팡이독소가 광범위하게 오염되어 있었으며, 특히 DON과 ZEN은 모든 배합에서 확인되었다. 소 사료의 경우 DON과 ZEN은 평균 $812.1\;{\mu}g/kg$과 $147.2\;{\mu}g/kg$의 오염도를 보여 닭 사료나 돼지 사료보다 약 4배정도 높은 오염도를 보였으며, 그 원료로 사용된 단미 사료를 조사해본 결과 수입 단백피가 주요 오염원인 것으로 확인됐다.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1994년도 추계 학술발표회
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• pp.135-136
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• 1994

Anionic water dispersible copolyesters were synthesized by the polycon-densation of dimethyl isophathalate/5-sodium sulfo dimethyl isophathalate with ethylene glycol/diethylene glycol. Structrual analyses such as NMR, Irm WAXD analyses were done and copolyesters were found to be correctly synthesized. Relation between feed ratio and composition ratio of EG/DEG in copolyesters was confirmed by NMR analysis. Solubility test was done to find out optimum conditon of DMS feed ration of 10 mol% in dimethyl esters. Water resistance of copolyesters decreased with the increase of DMS or DEG molar feed ratio.

• Animal Bioscience
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• 제35권12호
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• pp.1881-1891
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• 2022

Objective: The present study aimed to quantify the effects of fermented soybean meal (FSBM) on broiler chickens' performance by employing a meta-analysis approach. Methods: A total of 16 studies were included in the database after being systematically selected using a PRISMA protocol. Hedges' g effect size was used to quantify pooled standardized mean difference (SMD) using random-effects models at 95% confidence intervals (95% CI). Publication bias among studies was computed with Egger's test and visualized using funnel plots. Results: Results indicated that dietary FSBM inclusion increased final body weight (BW) (SMD = 0.586, 95% CI: 0.221 to 0.951, p = 0.002) of broiler chickens, particularly in starter period (SMD = 0.691, 95% CL: 0.149 to 1.233, p = 0.013) while in the finisher period, the effect was weaker (SMD = 0.509, 95% CI: 0.015 to 1.004, p = 0.043). Average daily gain (ADG), feed intake (FI), and feed conversion ratio (FCR) were not affected with FSBM inclusion when compared to control. Subgroup analysis revealed that FI increased in starter period (SMD = 0.582, 95% CI: 0.037 to 1.128, p = 0.036). When considering types of microorganism as moderating variables in the subgroup analysis, we found that Aspergillus oryzae, mixed probiotics+bromelain protease, Bacillus subtilis, and Lactobacillus bacteria significantly increased ADG and FI (p<0.01). Additionally, either Bacillus subtilis+protease or Bacillus subtilis alone decreased FCR (p<0.001). However, meta-regression analysis showed that levels of FSBM inclusion had no effects on final BW (p = 0.502), ADG (p = 0.588), FI (p = 0.861), and FCR (p = 0.462). Conclusion: Substituting SBM in broiler chickens' diet with FSBM improved BW of broiler chickens, especially in the starter period whereas the effects on ADG, FI, and FCR were mostly dependent on microbial strains used for fermentation.

• 한국임상수의학회지
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• 제25권2호
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• pp.67-72
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• 2008

The aim of this study was to investigate the efficacy of Lactobacillus spp. W44 and J124 strain isolated from Kimchi on the growth rate, average daily gain (ADG), feed conversion and change of intestine microflora in the weaning piglets. In the experiment 1, growth rate was significantly increased to $28.5\;{\pm}\;4.3\;kg$ and $27.6\;{\pm}\;3.3\;kg$ after oral administration of W44 and J124 strain as feed additives, respectively (p<0.05). ADG and feed conversion were also significantly improved after administration during 44 experiment days (p<0.05). In the analysis of intestinal microflora, the number of Lactobacillus spp. in the experiment groups was significantly increased 100 to 1,000 times compared to those of control group. In the experiment 2, the efficacy of W44 and J124 strains on the growth rate, ADG, feed conversion and change of intestine microflora were reconfirmed significantly (p<0.05). However, there were no significant differences on feed conversion in the W44 bead and J124 bead groups. In summary, our results suggest that W-44 and J-124 stains from Kimchi have a significant effect on the weight gain and feed conversion, and it may be useful probiotic strains for the weaning piglets as feed additives.