• Journal of Aerospace System Engineering
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• v.13 no.4
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• pp.66-73
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• 2019

The objective of this study was to evaluate the structural safety of the basic design for the linear actuator for the flap control of aircrafts. The kinetic behavior of the linear actuator was determined using the multi-body dynamics (MBD) analysis, and the contact force was calculated to be used as input data for the structural analysis based on the finite element analysis. In the structural analysis, the thermal and static behaviors of the linear actuator satisfying the designed velocity were examined, and the structural safety of the linear actuator evaluated. Moreover, the dynamic behaviors of the key components of the linear actuator were investigated by the modal analysis. The actuation rod linearly moved with about 5 mm/s when the motor operated at 225 rpm and the maximum contact force of 32.83 N occurred between two driving gears. Meanwhile, the structural analysis revealed that the maximum thermal and static stresses were 1.57% and 78% of the yield strength of steel, respectively, and they were in a safe range of the structure. In addition, the linear actuator for the basic design is stable to the resonance by avoiding the natural frequencies of the components.

• Journal of Animal Science and Technology
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• v.63 no.1
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• pp.180-190
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• 2021

This study aimed to determine the carcass and meat quality of broiler chickens based on the slaughter age (28, 30, 32, and 34 days). The carcass characteristics included live and carcass weights, carcass rate, dressing rate, and retail cut weight. The meat quality properties were determined through proximate composition, pH, color, water holding capacity (WHC), cooking yield, and shear-force. The broiler chicken live, carcass, breast, thigh, and wing weights significantly increased with the slaughter age (p < 0.05); the tenderloin weight also exhibited a similarly increasing trend. However, the carcass rate of the day 28 sample was significantly lower than the other samples (p < 0.05). The protein and ash contents of the breast exhibited an increasing trend with increasing slaughter age. The protein content of the thigh of the day 28 sample was significantly lower than that of the other samples (p < 0.05), while the ash contents of the day 28 and 30 samples were significantly lower. The redness of the breast showed an increasing trend, and the pH and lightness of the thigh exhibited a decreasing trend with slaughter age. The WHC and cooking yields of the day 30 and 32 breast and thigh samples were significantly higher than those of the day 28 and 34 samples (p < 0.05). The breast and thigh shear-force of the day 30-34 samples were significantly higher than those of the day 28 sample (p < 0.05). The present study showed that even with a twoday difference in slaughter age, the broiler chicken meat quality showed a significant difference in several characteristics.

• International Journal of Advanced Culture Technology
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• v.9 no.1
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• pp.177-182
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• 2021

The fourth industrial revolution based on information and communication technology (ICT) becomes the center of society, and the overall industrial structure is also changing significantly. ICT refers to the hardware of information devices and the software technologies required for the operation and information management of these devices, and any means of collecting, producing, processing, preserving, communicating and utilizing them. ICT is integrated into industries and services or combined with new technologies in various fields such as robotics and nanotechnology to connect all products and services to the network. The development of ICT, which continuously creates new products and services, has spread to all sectors of the industry, affecting not only daily life but also the livestock sector recently. In agriculture, ICT technology can reduce production costs by efficiently managing labor and energy because it can improve quality and yield based on data on environmental and growth information such as temperature, humidity, light and soil. In particular, smart livestock is considered suitable for achieving livestock management goals because it can reduce labor force and improve productivity by remotely and automatically managing accurate information necessary for raising and breeding livestock with ICT devices. The purpose of this study is to propose the need for ICT technology by comparing farm productivity before and after ICT is introduced. The method of the study is to compare the productivity before and after the introduction of ICT in Korean beef farms, pig farms, and poultry farms. The effectiveness of the study proved the excellence of ICT technology through the production results before ICT introduction and the productivity improvement case of livestock farms that efficiently operated manpower management and reduced labor force after ICT introduction. The conclusion of this paper is to present the need for smart livestock through ICT adoption through case study results.

• Food Science of Animal Resources
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• v.41 no.2
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• pp.247-260
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• 2021

This study aimed to determine the physicochemical properties (proximate composition, color, pH, salinity, water holding capacity (WHC), curing yield, and shear force) and sensory properties (electric nose and sensory evaluation) of Bulgogi sauce with added crust derived from dry-aged beef loin. Increasing the amount of crust in the Bulgogi sauce tended to increase the protein content, fat content, and pH. Uncooked Bulgogi also tended to have elevated fat content, ash content, pH, and shear force. Increasing the crust content tended to decrease the water content, lightness, redness, and yellowness of Bulgogi sauce. The yellowness of uncooked Bulgogi with 6%-12% crust in sauce was significantly lower than that of the control (no crust) and the sample with 3% crust in sauce (p<0.05). The redness of the cooked control Bulgogi was significantly lower than that of the samples with crust in sauce (p<0.05). The WHC of uncooked Bulgogi with 6%-12% crust in sauce was significantly higher than that of the control and the sample with 3% crust in sauce (p<0.05). The flavor, texture, and overall acceptability of the Bulgogi with 9% crust in sauce were significantly higher than those of the control (p<0.05). These findings showed that the crust did not degrade the physicochemical properties of Bulgogi sauce and meat. The sensory characteristics of Bulgogi marinated with 9% crust in sauce were rated the best as persensory evaluation. Therefore, crust is a suitable flavor enhancer for Bulgogi sauce, and a 9% addition amount is optimal in terms of quality.

• Structural Engineering and Mechanics
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• v.82 no.1
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• pp.107-120
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• 2022

The bracing members capable of active control against seismic loads to reduce earthquake damage have been widely utilized in construction projects. Effectively reducing the structural damage caused by earthquake events, bracing systems equipped with retrofitting damper devices, which take advantage of the energy dissipation and impact absorption, have been widely used in practical construction sites. Shape Memory Alloys (SMAs) are a new generation of smart materials with the capability of recovering their predefined shape after experiencing a large strain. This is mainly due to the shape memory effects and the superelasticity of SMA. These properties make SMA an excellent alternative to be used in passive, semi-active, and active control systems in civil engineering applications. In this research, a new system in diagonal braces with slit damper combined with SMA is investigated. The diagonal element under the effect of tensile and compressive force turns to shear force in the slit damper and creates tension in the SMA. Therefore, by creating shear forces in the damper, it leads to yield and increases the energy absorption capacity of the system. The purpose of using SMA, in addition to increasing the stiffness and strength of the system, is to create reversibility for the system. According to the results, the highest capacity is related to the case where the ratio of the width of the middle section to the width of the end section (b₁/b) is 1.0 and the ratio of the height of the middle part to the total height of the damper (h₁/h) is 0.1. This is mainly because in this case, the damper section has the highest cross-section. In contrast, the lowest capacity is related to the case where b₁/b=0.1 and the ratio h₁/h=0.8.

• Earthquakes and Structures
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• v.23 no.2
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• pp.139-150
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• 2022

In most self-center braces, decreasing residual deformation is possible only by increasing pretension force, which results in lower energy dissipation capacity. On the other hand, increasing energy dissipation capacity means higher values of residual deformation. The goal of this research was to find the best design for a self-centering buckling restrained brace (SC-BRB) system by balancing self-centering capability and energy dissipation. Three, six, and nine-story structures were investigated using OpenSees software and the TCL programming language to achieve this goal. For each height, 62 different SC-BRBs were considered using different values for the pretension force of cables, the area of the buckling restrained brace (BRB) core plate, and the yield stress of the core plate. The residual deformation and dissipated energy of all the models were calculated using nonlinear analyses after cyclic loading was applied. The optimum design for each height was determined among all the models and was compared to the structure equipped with the usual BRB. The residual deformation of the framed buildings was significantly reduced, according to the findings. Also the reduction of the energy dissipation was acceptable. The optimum design of SC-BRB in 6-story building has the most reduction percent in residual deformation, it can reduce residual deformation of building 83% while causing only a 57% of reduction in dissipated energy. The greatest reduction in residual deformation versus dissipated energy reduction was for the optimum SC-BRB design of 9-story building, results indicated that it can reduce residual deformation of building 69% while causing only a 42% of reduction in dissipated energy.

• Food Science of Animal Resources
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• v.44 no.3
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• pp.635-650
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• 2024

In this study, we analyzed the physicochemical and sensory properties of black goat jerky marinated with various spices (non-spice, control; rosemary, RO; basil, BA; ginger, GI; turmeric, TU; and garlic, GA). The physicochemical properties of black goat jerky analyzed were pH, water holding capacity, color, cooking yield, shear force, and fatty acid composition. The sensory characteristics were analyzed through the aroma profile (electronic nose), taste profile (electronic tongue), and sensory evaluation. The pH and water holding capacity of the GI showed higher values than the other samples. GI and GA showed similar values of CIE L^* and CIE a^* to that of the control. The shear force of the GI and TU was significantly lower than that of other samples (p<0.05). Regarding fatty acid composition, GI showed high unsaturated and low saturated fatty acid contents compared with that of the other samples except for RO (p<0.05). In the aroma profile, the peak area of hexanal, which is responsible for a faintly rancid odor, was lower in all treatment groups than in the control. In the taste profile, the umami of spice samples was higher than that of the control, and among the samples, GI had the highest score. In the sensory evaluation, the GI sample showed significantly higher scores than the control in terms of flavor, aroma, goaty flavor, and overall acceptability (p<0.05). Therefore, marinating black goat jerky with ginger powder enhanced the overall flavor and reduced the goat odor.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.2
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• pp.211-222
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• 2011

In this paper a structural analysis of the PWR(pressurized water reactor) canister with 102cm diameter is carried out to evaluate the structural safety of the canister for the impact force occurring at the moment of collision with the ground in the falling plumb down accident from the carriage vehicle which may happen during the canister handling at the spent nuclear fuel disposal repository. For this, a rigid body dynamic analysis of the canister is executed to compute the impact force using the commercial CAE system, RecurDyn, and a nonlinear structural analysis is performed to compute stresses and deformations occurring inside the canister for this computed impact force using the commercial FEM code, NISA. From these analysis results, the structural safety of the canister is evaluated for the falling plumb down accident from the carriage vehicle due to the inattention during the canister handling at the repository. The rigid body dynamic analysis performed assuming the canister as a rigid body shows that the canister falls plumb down to the ground in two types. And also it shows that early collision impact force is the biggest one and following impact forces decrease gradually. The height of the carriage vehicle in the repository is assumed as 5m in order to obtain the stable structural safety evaluation result. The nonlinear structural analysis of the canister is executed for the biggest early impact force. The structural analysis result of the canister shows that the structural safety of the PWR canister is not secured for the falling plumb down accident from the moving carriage vehicle because the maximum stresses occurring in the cast iron insert of canister are bigger than the yield stress of the cast iron.

• Food Science of Animal Resources
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• v.25 no.3
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• pp.322-327
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• 2005

This study was intended to provide basic information which might be useful in increasing added values to the pork from Korean native black pigs (KNP), through comparative evaluation on carcass characteristics and meat qualities between KNP and four exotic breed groups including Duroc (DD), Landrace (LL), Yorkshire (YY), and LYD-cross (1/4LL 1/4YY, 1/2DD), and the results were summarized as follows. Live weight carcass weight, dressed meat weight, skin weight, fat weight and bone weight of KNP were significantly (p<0.05) lower than those of DD, LL, YY and LYD-cross. Carcass yield and dressed meat yield were also significantly (p<0.05) lower in KNP than other 4 groups, however, total fat, skin, bone, kidney and kidney fat in percentage were significantly (p<0.05) higher for KNP than others. Dressed meat yield was highest for YY, followed by LYD-cross and KNP. Weight of belly was 6.12, 9.43, and 9.52 kg for KNP, YY and LYD-cross, respectively. Percent belly of KNP was $11.11\%$ while other groups ranged from 11.5 to $12.2\%$ Shear force value was not different among the treatments. KNP had significantly (p<0.05) lower water holding capacity (WHC), and cooking loss, but significantly (p<0.05) higher in juiciness comparatively. KNP had significantly (p<0.05) higher $a^{*}$ value while DD had significantly (p<0.05) lower than other breeds.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.3
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• pp.196-204
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• 2002

For the study of its stability when the screw has been fixed after sagittal split ramus osteotomy(SSRO) of the mandible, the methods of screw arrangement are classified into two types, triangular and straight. The angles of screws to the bone surface are classified as perpendicular arrangements, the $60^{\circ}$ anterioinferior screw, known as triangular, and the most posterior screw, called straight arrangement, thus there are four types. The finite element method model has been made by using a three dimensional calculator and a supercomputer. The load directions are to the anterior teeth, premolar region, and molar region, and the bite force is 1 Kgf to each region. The distribution of stress, the von-Mises yield strength, and safety of margin refer to the total sum of transformed energy have been studied by comparison with each other. The following conclusion has been researched : 1. When shear stress is compared, in the triangular arrangement in the form of "ㄱ", the anterosuperior screw is seen at contributing to the support of the bone fragment. In the straight arrangement, substantial stress is seen to be concentrated on the most posterior angled screw. 2. When the von-Mises yield strength is compared, it seemed that the stress concentration on the angled anteroinferior screw is higher, it shows a higher possibility of fracture than any other screw. In the straight arrangement, stress appeared to be concentrated on the most posteriorly angled screw. 3. When the safety margins of the transfomed energy are compared, the energy conduction is much greater in the case of the angled screw than in the case of the perpendicular screw. The triangular arrangement in the form of "ㄱ" shows a superior clinical sign to that of the straight arrangement. Judging from the above results, when the screw fixation is made after SSRO in practical clinical cases, two screws should be inserted in the superior border of mandibular ramus and a third screw of mandibular inferior border should be inserted in the form of triangular. All screws on the bony surface should be placed perpendicularly-$90^{\circ}$ angles apparently best promote bony support and stability.