• Asian-Australasian Journal of Animal Sciences
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• v.30 no.10
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• pp.1456-1463
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• 2017

Objective: To investigate the effect of host genetics on gut microbial diversity, we performed a structural survey of the fecal microbiota of four purebred boar pig lines: Duroc, Landrace, Hampshire, and Yorkshire. Methods: The V3-V4 regions of the 16S rRNA genes were amplified and sequenced. Results: A total of 783 operational taxonomic units were shared by all breeds, whereas others were breed-specific. Firmicutes and Bacteroidetes dominated the majority of the fecal microbiota; Clostridia, Bacilli, and Bacteroidia were the major classes. Nine predominant genera were observed in all breeds and eight of them can produce short-chain fatty acids. Some bacteria can secrete cellulase to aid fiber digestion by the host. Butyric, isobutyric, valeric, and isovaleric acid levels were highest in Landrace pigs, whereas acetic and propionic acid were highest in the Hampshire breed. Heatmap was used to revealed breed-specific bacteria. Principal coordinate analysis of fecal bacteria revealed that the Landrace and Yorkshire breeds had high similarity and were clearly separated from the Duroc and Hampshire breeds. Conclusion: Overall, this study is the first time to compare the fecal microbiomes of four breeds of boar pig by high-throughput sequencing and to use Spearman's rank correlation to analyze competition and cooperation among the core bacteria.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.1
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• pp.146-153
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• 1996

A SCARA type direct drive robot which can be used in the assembly operation was designed and manufactured. Graphite fiber epoxy composite material was used in the fabrication of the robot arm structure in order to improve the speed of the robot arm with a high damping effect. For model-based control and sensitivity analysis of system parameters, the dynamic model of robot arm and drive servo amplifier parameters such as equivalent gains of PWM driver and velocity gains of servo system were estimated from frequency response tests. The complete dynamic model for overall robot system was used in the simulation of the open-loop control. The simulation results agreed reasonably well to the experimental results. The feedforward control using the dynamic models improved the trajectory tracking performance, decreasing the tracking error by factor of three compared with PID control. This study found that the inverse dynamic model of the robot arm including the drive servo system showed better performances than the case of arm dynamic model only.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.413-418
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• 2001

Fundamental failure mode in a laminated composite pinned-joint is proposed to assess damage resulting from stress concentration in the plate. The joint area is a region with stress concentrations thus a complicated stress state exists. The modeling of damage in a laminated composite pinned-joint presents many difficulties because of the complexity of the failure process. In order to model progressive from initial to final, finite element methods are used rather than closed form stress analyses. Failure analysis must be a logical combination of suitable failure criteria and appropriate material properties degradation rules. In this study, the material properties which were obtained in previous study, the preparing process of the bearing strength test for a pinned joint CFRP composite plate subjected to in-plane loading at low temperature, and the FEM result of progressive damage model using ANSYS program are summarized to assess the structural safety of CFRP plate used in the magnetic supporting post of KSTAR(Korea Superconducting Tokamak Advanced Research).

• Membrane Journal
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• v.28 no.4
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• pp.243-251
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• 2018

Methane is one of the important greenhouse gases and methane is the major component of the biogas. A multiple stage membrane process was developed and analysed with the numerical analysis so that the mole fraction of methane in the final product could be kept higher than 0.95 and simultaneously the recovery of methane was also maintained higher than 99% from the biogas using 3 polysulfone hollow fiber membrane modules which were properly connected. As the feed pressure of the biogas, the mole fraction of methane in the biogas and the membrane area in the membrane module are increased, the methane mole fraction of the final product are found to be increased. However, a proper membrane area in the module should be carefully selected in order to achieve the satisfactory goal of 0.95 mole fraction of methane and 99% recovery of methane from the biogas. Even if the multiple membrane process is utilized with the properly selected membrane modules, the limited operating ranges have to be applied in the following parameters : the feed pressure, the flow rate, the mole fraction of methane in the biogas to get both the target methane concentration and the recovery rate of methane.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.13-14
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• 2012

Than fluorescent lamps or light bulbs, long life, small power consumption and to the development of modern technology, LED (Light Emitting Diode) devices have the advantage of easy control. For these reasons, using the LED device, lighting has been widely used. LED using optical fiber technology using LED lighting technology with the development of wireless communication technology is attracting attention again. Using LED lights this study analyzed the performance of the technology transfer and implementation of the information transmission system of the visible light communication using LED lighting of the White Visible Light Communication (VLC) based PC module transmitter and receiver modules. Has made a system that can transmit information more than the value of the initial distance ~ 50cm, depending on the presence or absence of the lens, in order to increase the efficiency of the LED modules with different efficiencies that could confirm the performance of the implementation of the research, analysis, and application methods. and about the possibility that you want to check.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.2
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• pp.266-272
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• 2001

An instrumental analysis of cooked beef was carried out along with sensory evaluation to find out the effect of Sarcodon aspratus on the physicochemical and sensory characteristics in comparision with kiwi fruit and pear. Transmission electron microscopy showed the muscle fiber started to be degraded when treated with Sarcodon aspratus(1,000unit) for 10 min at $25^{\circ}C$. No distinct sarcomere, A-band, and Z-line was observed when treated with Sarcodon aspratus for 60 min at same condition. The moisture content of cooked beef was increased in proportion to the increment of Sarcodon aspratus, kiwi fruit and pear. In the texture, shear force of cooked beef was decreased with the increment of Sarcodon aspratus, kiwi fruit and pear. In terms of color, L-value was decreased by addition of Sarcodon aspratus, whereas L-value was increased by addition of kiwi fruit and pear in dose-dependent manners. a-value and b-value was decreased with the increment of Sarcodon aspratus, kiwi fruit and pear. There were significant differences (p<0.05) in the sensory characteristics of the samples in which control was most preferred in taste and flavor. As the content of Sarcodon aspratus, kiwi fruit and pear was increased, the score of juiciness and tenderness was increased. In the overall acceptance, score of 0.05~0.1% Sarcodon aspratus and 10% pear was not different from that of control. Therefore, it can be concluded that 0.05~0.1% addition of Sarcodon aspratus might be desirable for the improvement of texture and juiciness of cooked beef.

• Composites Research
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• v.17 no.3
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• pp.1-7
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• 2004

In the vacuum assisted RTM (VARTM) process that has become the center of attention for manufacturing massive composite structures, a good evacuation of air in the fiber preform is recognized as the prime factor. The microvoids, or the dry spots, are formed as a result of improper gate/vent locations and the mold geometry. The non-uniform resin velocity at the flow front leads to the formation of microvoids in the fibers, whereas the air in the microvoids can migrate along with the resin flow during mold filling. The residual air in the internal voids of a composite structure may cause a degradation of the mechanical properties as well as the structural failure. In this study, a unified macro- and micro analysis methods were developed to investigate the formation and transport of air in resin during VARTM process. A numerical simulation program was developed to analyze the three-dimensional flow pattern as well as the macro- and microscopic distribution of air in a composite part fabricated by VARTM process.

• Composites Research
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• v.30 no.6
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• pp.331-337
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• 2017

The composite lattice structures have advantages of high specific stiffness and strength and are mainly applied to the structures of launch vehicles that carry the compressive load. However, since these structures are manufactured by filament winding technology, there are some defects and voids found in the knots. For these reasons, the stiffness and strength of the lattice structures have to be compared with finite element model for predicting design load. But, the full scale test is difficult because time and space are limited and the shape of structure is complex, and hence the simple and reliable test methods for examination of stiffness are needed. In this paper, subelements of composite lattice structures were prepared and compressive and bending test were conducted for examination of stiffness of helical and hoop rib. Test methods for subelements of composite lattice structures that has curved and twisted shape were supposed and compared with finite element analysis results.

• Journal of Community Nutrition
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• v.8 no.4
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• pp.171-176
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• 2006

The study aims to evaluate the nutritional status and influence of school meal intakes on RDA of primary school children in Akure community, Ondo State, Nigeria. A cross-sectional study was conducted among 728 primary school children aged between 6 and 15 years. Data were collected using interviewer-administered semi-structured questionnaires. The questionnaires collect information on demographic characteristics and home dietary intake of the subjects. The heights and weights of the children were measured using a standard procedure and height-far-age and weight-far-height z-score were determined. The children's school meal intakes were weighed for 4 days and samples were collected for chemical analysis. The results showed that 37.8% of the children were not wasted, 35.7% mildly wasted, 18.7% moderately wasted and 7.8% severely wasted. Also, 57.8% were not stunted, 29.3% mildly stunted, 11.0% moderately stunted and 1.9% were severely stunted. The subjects' home dietary intakes showed that 73.6% ate starchy food only, 19.9% ate protein based food, while 11.6% and 11.5% consumed fruits/vegetables and snacks to complement home meals respectively. The chemical composition of school meal was energy 379 - 413kcal, moisture content 5.9 -7.3g, carbohydrate 56.5 - 69.4g, fat 4.6 - 12.7g, crude fiber 0.1 - 2.4g, ash content 3.6 - 8.5g and protein 14.9 - 22.3g. The mineral contents were calcium 45.9 - 59.2mg, sodium 5004 - 59.6mg, zinc 2.3 - 3.1mg, magnesium 55.0 - 61.6mg, potassium 55.3 - 69.3mg, copper 0.2 - 0.3 mg, while others 1.3 - 1.9mg, 243 - 659mg and 831 - 9,510mg were iron, phosphorous and vitamin-A respectively. The contribution of school meals to subjects' RDA was within 2.9% and 1540%. In summary, school meal intake contributed positively to the RDA and nutritional status of the school children.

• Journal of Biomedical Engineering Research
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• v.23 no.2
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• pp.119-130
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• 2002

The nonlinear finite element program has been developed to analyze the design performance of an artificial hip prosthesis and long term behavior of a treated femur with stems made of composite material after cementless total hip arthroplasty(THA). The authors developed the three dimentional FEM models of femoral bone with designed composite stem which was taken with elliptic cross section of 816 brick elements under hip contact load and muscle farce in simulating single leg stand. Using the program, density changes, stress distributions and micromotions of the material femoral bone were evaluated by changing fiber orientation of stems for selected manufacturing method such as plate cut and bend mold. The results showed that the composite materials such as AS4/PEEK and T300/976 gave less bone resorption than the metallic material such as cobalt chrome alloy, titanium alloy and stainless steal. It was found that increasing the long term stability of the prosthesis in the femur could be obtained by selecting the appropriate ply orientation and stacking sequence of composite.