• 대한수의학회지
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• 제45권1호
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• pp.121-125
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• 2005

The present study was carried out to produce the hematological and blood chemical findings after hypophysectomy in rats. Hypophysectomy was performed by the parapharyngeal method and the sham surgery was performed for the control group. Two weeks after the operation, the body weight of the hypophysectomized and control rats was measured daily for 5 days. We deleted the rats the weight gain of which is less than 5 g during 5 days from the hypophysectomy group. The successful operation rate was approximately 40%. In the hypophysectomized and control rats, their blood samples were collected from posterior vena cava after celiotomy under generally anesthesia with ether. Hematological parameters such as erythrocyte count, leukocyte count, hemoglobin concentration, hematocrit level, and platelet count were determined by Animal Blood Counter. The erythrocyte count, hemoglobin concentration, and hematocrit level were lower significantly (p<0.01), and the leukocyte count was lower significantly (p<0.05) in hypophysectomy group compared with control group. But the plate count did not show significant difference (p>0.05) between hypophysectomy group and control group. Also, blood chemical parameters such as glucose, blood urea nitrogen (BUN), aspartate animotransferase, albumin, total protein, cholesterol, calcium, and magnesium in serum were determined. Except BUN concentration, all parameters were not affected by hypophysectomy. But the BUN concentration was higher significantly (p<0.01) in hypophysectomy group compared with control group.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권7호
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• pp.3455-3474
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• 2018

As a unique form of signed-digit representation, non-adjacent form (NAF) minimizes Hamming weight by removing a stream of non-zero bits from the binary representation of positive integer. Thanks to this strong point, NAF has been used in various applications such as cryptography, packet filtering and so on. In this paper, to improve the NAF conversion speed of the $NAF_w$ algorithm, we propose a new NAF conversion algorithm, called w-bit Shifting Non-Adjacent Form($SNAF_w$), where w is width of scanning window. By skipping some unnecessary bit comparisons, the proposed algorithm improves the NAF conversion speed of the $NAF_w$ algorithm. To verify the excellence of the $SNAF_w$ algorithm, the $NAF_w$ algorithm and the $SNAF_w$ algorithm are implemented in the 8-bit microprocessor ATmega128. By measuring CPU cycle counter for the NAF conversion under various input patterns, we show that the $SNAF_2$ algorithm not only increases the NAF conversion speed by 24% on average but also reduces deviation in the NAF conversion time for each input pattern by 36%, compared to the $NAF_2$ algorithm. In addition, we show that $SNAF_w$ algorithm is always faster than $NAF_w$ algorithm, regardless of the size of w.

• International Journal of Aeronautical and Space Sciences
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• 제11권1호
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• pp.19-25
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• 2010

A computational study for the optimal design of heat exchangers (HX) used in a high temperature and high pressure system is presented. Two types of air to air HX are considered in this study. One is a single-pass cross-flow type with straight plain tubes and the other is a two-pass cross-counter flow type with plain U-tubes. These two types of HX have the staggered arrangement of tubes. The design models are formulated using the number of transfer units ($\varepsilon$-NTU method) and optimized using a genetic algorithm. In order to design compact light weight HX with the minimum pressure loss and the maximum heat exchange rate, the weight of HX core is chosen as the object function. Dimensions and tube pitch ratio of a HX are used as design variables. Demanded performance such as the pressure loss (${\Delta}P$) and the temperature drop (${\Delta}T$) are used as constraints. The performance of HX is discussed and their optimal designs are presented with an investigation of the effect of design variables and constraints.

• 한국공작기계학회논문집
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• 제17권4호
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• pp.22-28
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• 2008

Friction stir welding(FSW) is an relatively new solid state joining process. A1606l-T6 aluminium alloy has gathered wide acceptance in the fabrication of light weight structures requiring a high strength to weight ratio and good corrosion resistance. This friction stir process(FSP) uses a non-consumable tool to generate frictional heat in the abutting surfaces. The welding parameters such as tool rotational speed, welding speed, etc., and tool pin profile playa major role in deciding FSP zone formation in A16061-T6 aluminium alloy. Tow different tool pin profiles have been used to fabricate the joints. The formation of friction stir processed zone has been analysed macroscopically. Tensile properties of the joints have been evaluated and correlated with the friction stir processed zone formation.

• 근관절건강학회지
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• 제22권3호
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• pp.167-176
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• 2015

Purpose: The purpose of this study was to identify the level of body perception, obesity, and factors associated with stages of exercise and dietary habits change in university students. Methods: A descriptive design was used. Data were collected from 279 university students using structured questionnaires. Results: The body perception was significantly associated with self rated health (F=27.89. p<.001), weight satisfaction (F=137.74. p<.001) and weight control interest (F=39.19. p<.001). The BMI was significantly associated with weight satisfaction (F=34.08. p<.001) and weight control interest (F=19.59. p=.003). But the body perception and BMI were not significantly associated with depression (F=2.17, p=.073, F=0.86. p=.462), the change of exercise (F=25.91. p=.055, F=20.34. p=.061), and dietary habits (F=12.96. p=.677, F=11.29. p=.505). The related factors affecting the change of exercise behavior were counter conditioning, self efficacy, eating behavior, and helping relationship, including 30.4% R-square. The related factor affecting the change of dietary habit was only eating behavior, including 20.0% R-square. Conclusion: This study can provide useful information to develop effective programs for the change of exercise and dietary habits considering university students' stages of change according to the transtheoretical model.

• Structural Engineering and Mechanics
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• 제74권4호
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• pp.515-520
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• 2020

In the modern era, the world is facing unprecedented challenges in form of environmental pollution and international agencies are forcing scientists and materialists to look for green materials and structures to counter this problem. Composites based on renewable sources like plant based fibres, vegetable fibres are finding increasing use in interior components of automobile vehicles, aircraft, and building construction. In the present study, jute and flax fibre based composites were developed and tested for assessing their suitability for possible applications in interior cabin and parts of automobile and aerospace vehicles. Matrix system involves epoxy as resin and fibre weight fractions used were 45% and 55% respectively. Composites samples were prepared as per American society for testing and materials (ASTM) standard and were tested for individual fiber tensile strength, composite tensile strength, and flexural strength to analyse its behavior under various loading conditions. The results revealed that the Jute fibre composites possess enhanced mechanical properties over Flax fibre composites.

• 국제초고층학회논문집
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• 제3권1호
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• pp.1-8
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• 2014

When seismic isolation system is applied to high aspect-ratio (height/wide-ratio) steel structures, there are several problems to be taken into consideration. One is lifting up tensile force on the isolation bearing by overturning moment caused by earthquake. Another is securing building stiffness to produce seismic isolation effects. Under these conditions, this paper reports the structural design of high-rise research building in the campus of Tokyo Institute of Technology. With the stepping-up system for the corner bearings, the narrow sides of single span framework are designed to concentrate the dead load as counter-weight for the tensile reaction under earthquake. Also we adopted concrete in-filled steel column and Mega-Bracing system covering four layers on north & south framework to secure the horizontal stiffness of the building.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.100.3-100
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• 2001

This article deals with the development of a mathematical model for the finishing polycarbonate polymerization process using a horizontal rotating disk-ring reactor with counter-current gas sweeping and the performance analysis of the reactor system by using the model. Here we intend to propose a model describing the reactor system consisting of two phases, in which by-product phenol is removed from the polymer of high molecular weight compatible with the products of commercial grades. The vapor phase is represented by a tanks-ln-series model while the polymer melt phase is regarded as a plug flow reactor.

• 통상정보연구
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• 제7권4호
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• pp.435-453
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• 2005

This paper suggests several strategies for promoting Trade and Foreign Direct Investment cooperation to the Korean government and companies as follows ; For Korean government, its trade policy would be given much weight on the import from the Vietnam in the early developing stage. This import could be compensated and increased with the counter export of Korean products like the industrial goods. For Korean companies, they would make haste to invest and develop the abundant energy and natural resources in Vietnam. Their desirable strategies would be moving small scale projects into large ones, production partnerships with the foreign developed and experienced companies, and international joint ventures for using inward FDI incentives. The long range vision and perseverance are indispensable for promoting trade and foreign direct investments between and Korea and Vietnam and both parties' win-win results and development in the end.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 C
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• pp.1193-1195
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• 1997

The chief advantage of these NCI, from a handling viewpoint. was an up to 90% weight reduction over their porcelain counter. Diagnosis and the life expectancy of NCI for transmission lines depend on a number of factors, many of which are associated with natural tracking breakdown, while others are related to manufacturing conditions. Recently The importance of optimizing a NCI for good performance under a wide variety of test condition and diagnosis is emphasized ; as well as the increased importance of natural breakdown testing. Today, at transmission lines, NCI have become very popular at 154 through 345 kV.