• Asian-Australasian Journal of Animal Sciences
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• 제31권4호
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• pp.522-528
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• 2018

Objective: This study evaluated inclusion of buckwheat silage to the diet of growing lambs in terms of meat quality as compared to maize silage. Methods: Buckwheat, rich in total phenols (TP, 33 g/kg dry matter [DM]), was harvested at the end of the milk stage and ensiled in 40 kg plastic bags after wilting (294 g/kg silage DM). A total of 18 growing lambs ($21.6{\pm}1.2$) were individually fed isonitrogenous and isoenergetic total mixed rations (TMR) for 75 d that either contained buckwheat or maize silage at DM proportions of 0.50. At the end of feeding trail all lambs were slaughtered to assess carcass characteristics and meat quality. Results: Buckwheat silage increased (p<0.01) the DM intake of lambs as compared to maize silage, but had no effects (p>0.05) on live weight gain and feed efficiency. Carcass weight, dressing percentage, meat pH, water holding capacity, cooking loss, shear force ($kg/cm^2$), and total viable bacteria count of meat did not differ (p>0.05) between the treatments. However, TP content of meat increased (p<0.001) by feeding buckwheat TMR. Feeding buckwheat TMR also decreased (p<0.05) the b* values of meat. Conclusion: The results provide that buckwheat silage is palatable and could successfully include TMR of growing lambs with no adverse effects on performance, carcass and meat quality. Additionally, feeding buckwheat silage to lambs offers increased TP in meat.

• Transactions of the Korean Society of Mechanical Engineers A
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• 제30권5호
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• pp.609-614
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• 2006

Recently linear motor has been used mainly for high speed feeding performance of machine tools. The advantages of linear motor are not only high speed but high accuracy, because it is not required the coupling and ballscrew for converting rotary to liner motion. Before applying in different moving system, the dynamometer is necessary to test the performance. In Korea, the linear motor is producing in a couple of company However, the liner motor dynamometer is not commercialized yet, like as rotary motor dynamometer. In this paper, a linear motor dynamometer is designed and manufactured using a MR damper. The dynamometer system developed in this study could be used for testing the positioning accuracy fur different loading conditions, traction forces, dynamic performance and so on.

• Journal of KSNVE
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• 제9권6호
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• pp.1210-1217
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• 1999

This paper presents schematic process of identifying the principal cause to make the vibration problem of rotating circular saws. In the tandem pencil slat saw lines, feeding of cedar blocks is often stopped because excessive motro current is required in a saw motor. These events are called "kick-offs" in technical reports. Research on saw behavior at kick-offs is required to understand are reduce the frequency and severity of kick-offs events. This research aims at finding out the principal cause of kick-offs, and evloving design improvements for high cutting performance with fewer and less severe kick-offs. Measurements of critical speed, cutting force, cutting temeprature and dynamic displacements are carried out to observe the instability mechanism and also to obtain saw design parameters for the numerical analyses. And the numerical analyses involving FEM and multiple scale method are utilized to show the possibility of the principal cause.pal cause.

• Journal of Institute of Control, Robotics and Systems
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• 제15권7호
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• pp.675-682
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• 2009

Instead of direct driving like BLDC, the induction principle is adopted as a driving one for planar stage. The stage composed of four linear induction motors put in square type is activated by two-axial forces; low-frequency attractive force and thrust force of the linear induction motors. Here, the modified vector control whose new inputs are q-axis current and dc current biased to three phase current instead of d-axis current or flux current is applied extensively to overall motion of the stage. For the developed system, the precision step test and the constant velocity test are tried to guarantee its feasibility for TFT-LCD pattern inspection. However, to exclude a discontinuity due to phase shift and minimize a force ripple synchronized with the command frequency, the initial system is revised to the antagonistic structure over the full degree of freedom. Concretely describing, the porous air bearings guide an air-gapping of the stage up and down and a pair of liner induction motors instead of single motor are activated in the opposite direction each other. The performances of the above systems are compared from trapezoid tracking test and sinusoidal test.

• The Transactions of The Korean Institute of Electrical Engineers
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• 제64권3호
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• pp.492-497
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• 2015

An overhead rigid conductor system is mainly applied to the subway and recently studies on the rigid system have been conducted for applications such as tunnels of high-speed line and speed improvement of a conventional lines up to 250km/h. Power feeding performance which is the most important in a rigid system can be measured by contact force and characteristics of this contact force are related to the shape and material of the R-BAR. In this paper, we analyze the measurements of contact force, current heating temperature, impedance of a rigid conductor which was developed in Korea, after that we compare static characteristics of home and abroad rigid conductors which have various shapes and materials.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• 제18권6호
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• pp.629-635
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• 2009

In this research, KP-4, one of the plastic mold steels, was coated with the AlTiN from one layer to four layers by the PVD method in the $\Phi$ 8mm cemented carbide ball end mill. Coated KP-4 was processed with various conditions. For example, slope of $15^{\circ}$, $30^{\circ}$ and $45^{\circ}$ the spindle rotation speed was changed from 10,000rpm to 16,000rpm, the tool feeding speed was changed from 1,300mm/min to 1,700mm/min, the depth of cut was also changed from 0.3mm to 0.9mm, and etc. Cutting component force according to the coating layer number, and surface roughness were studied. The cutting component force showed a good agreement better the up ward direction than the down ward direction under all experimental conditions. In case of the condition per the material shape, it was lessen when the tool have larger angle because the average effective diameter of the tool is larger. The surface roughness showed good condition in case of the up ward than the down ward direction. And, in the 3rd layer of AlTiN coating, it showed the most suitable condition.

• Asian-Australasian Journal of Animal Sciences
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• 제20권11호
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• pp.1746-1753
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• 2007

Steers (n = 335) of known genetic background from four fundamentally different growth types were subjected to two production systems to study differences in cooking loss (CL), tenderness, and chemical composition. Growth types were animals with genetic potential for large mature weight-late maturing (LL), intermediate mature weight-late maturing (IL), intermediate mature weight -early maturing (IE), and small mature weight-early maturing (SE). Each year, in a nine-year study, calves of each growth type were weaned and five steers of each growth type were developed on pasture or feedlot and harvested at approximately 20 and 14 mo of age, respectively. Data collected were CL and Warner-Bratzler shear force (WBS) for the Longissimus dorsi (LM), Psoas major (PS), and Quadriceps femoris (QF) muscles. Chemical composition was also determined from the right fore- and hindquarter. Data were analyzed using least squares analysis of variance for unequal subclass numbers. The beef growth $type{\times}production$ system interaction was significant for CL and WBS of the LM and ash in the lean trim of the forequarter. Growth types of LL and IL had greater (p<0.05) mean percentage CL in the PS and QF muscles than did IE and SE steers. Growth type LL had the highest (p<0.05) mean for both moisture and protein in the fore- and hindquarters; while SE had the lowest numerical mean value for moisture and protein in the fore- and hindquarters. Shear force of the PS did not differ (p>0.05) among steers of the four growth types. Increasing challenges to the cattle feeding industry may dictate that pasture development play a larger role in future production regimes. Producers should strive to match genetic growth type with available resources in order to remain viable and continue producing a quality product.

• Animal Bioscience
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• 제35권11호
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• pp.1771-1786
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• 2022

Objective: Inosine monophosphate (IMP) is a key factor that imparts of meat flavor. Differences in the IMP content in the muscles were evaluated to improve chicken meat quality. Methods: For this study, the IMP content was detected by high performance liquid chromatography. The gene expression profiles of Jingyuan chickens with different feeding patterns and different sexes were analyzed by RNA-sequencing (RNA-seq). Results: Breast muscle IMP content in free-range chickens was extremely significantly higher than that of caged chickens (p<0.01). Breast muscle IMP content in hens was also higher than that of cocks, but the difference was not significant. Correlation analysis showed that the breast muscle IMP content in caged hens and cocks was negatively correlated with the shear force, and the breast muscle IMP content in free-range hens was significantly negatively correlated with the shear force (p<0.05). The two key genes associated with IMP synthesis in chickens with different feeding patterns were glutamate-ammonia ligase (GLUL) and phosphodiesterase 10A (PDE10A). Bioinformatics analysis revealed that the GLUL and PDE10A genes are involved in glutamine biosynthesis and purine salvage pathways respectively. In addition, GLUL expression was positively correlated with the IMP content in caged and free-range chickens, and PDE10A expression was significantly positively correlated with the IMP content in caged and free-range chickens (p<0.05). Conclusion: These findings will facilitate the comprehension of the deposition of IMP in the muscles and thereby aid the process of selection and breeding of good quality local chickens.

• Journal of Aquaculture
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• 제16권1호
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• pp.1-7
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• 2003

A new technique combining forced-feeding and dorsal aorta cannulation was developed to monitor concentration of nutritions in the blood circulation and their metabolites in rainbow trout. To study the effect of dorsal aorta cannulation on stress, 30 rainbow trout (523$\pm$5.4 g; Mean$\pm$SD) were divided into 6 groups of 5 individuals each. A group was anesthetized and blood samples were taken at 0, 3, 6, 12, 24 or 48 h after dorsal aorta cannulation. Hematocrit peaked at 6 h and returned to 0 values by 12 h after dorsal aorta cannulation. Plasma cortisol and glucose concentrations also peaked at 6 h and returned to 0 values by 48 h after dorsal aorta cannulation. Based on the plasma cortisol and glucose concentrations, the rainbow trout recovered from the operation of dorsal aorta cannulation within 48 h. To compare the patterns of plasma free amino acid concentrations after force-feeding in the fish with dorsal aorta cannulation, 5 dorsal aorta cannulated individuals (511$\pm$6.2 g) were kept in a cage. After 48 h starvation, they were anesthetized and blood samples were taken at 0, 4, 8, 12, 24, 36 or 48 h after forced-feeding. The concentration of all plasma free amino acids, except isoleucine, leucine, phenylalanine, and tryptophan, also peaked at 4 h and returned to 0 values by 24 h after feeding. The combined technique allows forced-feeding and repeated sampling of blood in rainbow trout with minimum stress.

• Journal of Animal Science and Technology
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• 제46권5호
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• pp.811-820
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• 2004

Objectives of this study was to determine the comparisons of physico-chemical characteristics in crossbred pigs(Korean native breed ${\times}$ Landrace breed) by feeding periods. A total of 150 pigs were sampled from commercial farm, and assigned into three treatedrnents. Feeding peirods of Tl, T2 and T3 were below 200 days, 220-220 days, over 220 days, respectively. Live weight, carcass weight and backfat thickness were significantly(P<0.05) increased with feeding period increased, and final grade score have significantly(P<0.05) lower when feeding period was increased. pH and water content were significantly(P<0.05) lower when feeding period was increased(over 220days). However, intramuscular fat have no significantly different among the treatments. $L^* and b^* were significantly(P<0.05) lower and a^*$ was significantly higher(P<0.05) when feeding period increased. Cooking loss was higher in the order of Tl > T3 > T2. Shear force values was significantly(P<0.05) decreased by feed period increase. In fatty acids, myristic acid, palmitic acid, stearic acid and saturated fatty acid(SFA) in T2 were significantly(P<0.05) lower in T2, whereas linolenic acid, unsaturated fatty acid(UFA), essential fatty acid(EFA), UFA/SFA and EFA/SFA were significantly higher in T2 compared with other treatment. However palmitoleic acid and arachidonic acid were no significantly different with feeding periods. As a result of this study, crossbred pigs was increased live weight and carcass weight with feeding periods. and improved meat color and tenderness with feeding periods. However, final grade score was decreased with feeding periods