• Asian-Australasian Journal of Animal Sciences
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• 제20권1호
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• pp.52-59
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• 2007

The present study was designed to assess whether dietary inorganic and organic selenium (Se) could affect antioxidant enzymes, including superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and glutathione-S-transferase (GST), and the level of malondialdehyde (MDA), a marker of lipid peroxidation, in the intestine, serum, liver, and gastrocnemius muscle of Korean native goats. A total of eighteen Korean native goats was allotted into three dietary groups, consisting of basal diet (CON), or basal diet with either 0.25 ppm inorganic (IOSEL) or 0.25 ppm organic Se (ORSEL), and fed the corresponding diets for 5 wks. Growth performance, including body weight and total gain, and blood biochemical profiles, including GSH-Px, were not significantly different between the three dietary groups. Also, the specific activities of SOD, GSH-Px, and GST, and the level of MDA in the intestinal mucosa and liver from goats were not substantially affected by either inorganic Se or organic Se. However, goats fed the diet containing organic Se showed a significant increase in GSH-Px and GST activities in the gastrocnemius muscle compared with those fed the basal diet. In conclusion, increased muscle GSH-Px and GST activities suggest that dietary organic Se may affect, at least in part, the antioxidant defense system in muscle of Korean native goats under the conditions of our feeding regimen.

• Industrial Engineering and Management Systems
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• 제12권4호
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• pp.406-415
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• 2013

The present study examines a set of financial ratios in predicting the up or down movements of stock prices in the context of a securities law, the Sarbanes-Oxley Act of 2002 (SOA), controlling for macroeconomic variables. Using the logistic regression with proxy betas to alleviate the incompatibility problem between the firm-specific financial ratios and macroeconomic indicators, we report evidence that financial ratios are meaningful predictors of stock price changes, which subdue the influence of macroeconomic indicators on stock returns, and more importantly that the SOA truly improves the stock price predictability of financial ratios for the markup sample. The empirical results further suggest that industry and time effects exist and that for the markdown sample the SOA actually deteriorates the predictive power of financial ratios.

• 동력기계공학회지
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• 제21권6호
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• pp.110-116
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• 2017

Recently the global warming caused by greenhouse gas has emerged as a global environmental problem. For this reason the continued efforts to reduce greenhouse gas emission by international cooperation and each country are in progress. Climate changing has been recognized as the world economy development from fossil fuel use is the culprit. The international maritime organization marine environment protection committee of the global warming reduction emerged restrictions on air pollution have been strengthened. Therefore, the author has investigated the effects of fuel temperature on the characteristics of combustion and performance, using an four-cycle, six cylinders and direct injection diesel engine. The results of cylinder pressure, rate of pressure rise, rate of heat release and specific fuel consumption were increased by changing of fuel temperature.

• Ocean Systems Engineering
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• 제8권3호
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• pp.281-312
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• 2018

Characteristics of a turbulence wind model control the magnitude and frequency distribution of wind loading on floating offshore wind turbines (FOWTs), and an in-depth understanding of how wind spectral characteristics affect the responses, and ultimately the design cost of system components, is in shortage in the offshore wind industry. Wind spectrum models as well as turbulence intensity curves recommended by the International Electrotechnical Commission (IEC) have characteristics derived from land-based sites, and have been widely adopted in offshore wind projects (in the absence of site-specific offshore data) without sufficient assessment of design implications. In this paper, effects of wind spectra and turbulence intensities on the strength or extreme responses of a 5 MW floating offshore wind turbine are investigated. The impact of different wind spectral parameters on the extreme blade loads, nacelle accelerations, towertop motions, towerbase loads, platform motions and accelerations, and mooring line tensions are presented and discussed. Results highlight the need to consider the appropriateness of a wind spectral model implemented in the strength design of FOWT structures.

• 한국기계가공학회지
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• 제11권4호
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• pp.173-179
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• 2012

In recent years, Magnesium(Mg) and its alloys have become a center of special interest in the automotive industry. Due to their high specific mechanical properties, they offer a significant weight saving potential in modern vehicle constructions. Most Mg alloys show very good machinability and processability, and even the most complicated die casting parts can be easily produced. In this study, Microstructure, Vickers hardness and tensile tests were examined and performed for each specimen to verify effects of forming conditions. Also to verify upsettability and forming limit of the specimen at room temperature and elevated temperature, upsetting experiments were performed. For comparison, experiments at elevated temperature were performed for various Mg alloy, such as AZ31, AZ91, and AM50. The experimental results were compared with those of CAE analysis to propose forming limit of Magnesium alloys.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2004년도 유체기계 연구개발 발표회 논문집
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• pp.680-686
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• 2004

Recently, the application of variable geometry turbocharger (VGT) to the high speed direct injection (HSDI) diesel engine has gained more and more interest in automotive industry. A steady state experimental investigation has been undertaken on a 1.5L HSDI diesel engine to verify the benefits of VGT comparing to the standard engine having a waste gate turbocharger (WGT). Specifically, part load performances (e.g., fuel economy and emission) have been investigated under various vane angles of the VGT. The results show that the real exhaust gas recirculation (EGR) rate as well as the pumping loss is very important to improve break specific fuel consumption (BSFC). It was previously known that the pumping loss only is a main parameter. In addition, the trade-off relationship between BSFC and NOx according to boost pressure, and the decreasing tendency of NOx with increasing real EGR rate have been verified. 1-D numerical analysis also has been performed, and the numerical results are in good agreement with experimental results.

• 대한안전경영과학회지
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• 제18권3호
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• pp.147-154
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• 2016

This paper suggests a specific model that could efficiently improve the interaction and the interface between MES(Manufacturing Execution System) server and PDA terminal through RFID(Radio Frequency Identification) system and bar-code system in automative transmission shipment place of the finished assembly parts. The proposed model shows that the new method by RF-Tag system can more efficiently perform to reduce processing time and loading time for shipment, compared with the current approach by bar-code system. It is noted in case of the method by RF-Tag that the effects of proposed model are as follows; (a) While the shipping lead time per truck for carrying by the current method was 35 minutes, the shipping lead time by the new method was 15 minutes. (b) While the accuracy for carrying by the current method was 50%, the accuracy by the new method was 99%.

• 유통과학연구
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• 제10권5호
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• pp.19-28
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• 2012

The study examines the performance and its relationship with capital structure and agency cost with respect to the industrial configurations and economic groups of Pakistan Economy. The study employs data set of 334 listed joint stock companies from the nonfinancial sectors for the period of 1999-2009 from cotton and textile, engineering, chemical, sugar, cement, fuel and energy, paper and board, transport and communication, and miscellaneous economic groups. Pooled data from the Panel data methodology has been applied to observe the significance of different performance measures through determinant of capital structure and agency costs with special focus on the leverage and cash flows as the direct determinant and interactive variables. The empirical test results using redundant variable tests demonstrate support for agency theory in the context of Pakistan's industrial configurations. The implications of the study point towards more investigations on the subject using industrial configurations as control and moderating variables.

• 약학회지
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• 제18권4호
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• pp.236-242
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• 1974

Extrusion-spheronization processing combination was used to produce spherical granules with experimental formulations which contain microcrystalline cellulose as a diluent. The produced granules were compared on the basis of the following physical properties ; (a) bulk density, (e) porosity, (f) friabillity and (g) dissolution rate. With the specific experimental formulations used in this study, the increased plate rotational speeds of Marumerizer (400-1200rpm) produced continually more spherical material and also the obtained data indicated that the particle size distribution and dissolution rate depend upon the amount of microcrystalline cellulose used. As a result, the spherical granule preparation with microcrystalline cellulose has good properties in flow rate, packing propertyu and friability and offers a suitable method of granule preparation in pharmaceutical industry.

• International Journal of Computer Science & Network Security
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• 제21권6호
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• pp.54-60
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• 2021

Monte-Carlo GO is a computer GO program that is sufficiently competent without using knowledge expressions of IGO. Although it is computationally intensive, the computational complexity can be reduced by properly pruning the IGO game tree. Here, I achieve this by using a potential model based on the knowledge expressions of IGO. The potential model treats GO stones as potentials. A specific potential distribution on the GO board results from a unique arrangement of stones on the board. Pruning using the potential model categorizes legal moves into effective and ineffective moves in accordance with the potential threshold. Here, certain pruning strategies based on potentials and potential gradients are experimentally evaluated. For different-sized boards, including an official-sized board, the effects of pruning strategies are evaluated in terms of their robustness. I successfully demonstrate pruning using a potential model to reduce the computational complexity of GO as well as the robustness of this effect across different-sized boards.