• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.11a
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• pp.25-27
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• 1993

The effect of alpha$_1$-adrenergic stimulation on cardiac automaticity changes during myocardial development. To illustrate, in isolated tissues from the mature canine heart, alpha$_1$-adrenergic stimulation usually induces a decrease in automatic rate. On the other hand, many early neonatal fibers exhibit an increase in automatic rate In response to alpha$_1$-agonists, which is not seen in the adult.

• Journal of Pharmaceutical Investigation
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• v.6 no.3
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• pp.14-19
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• 1976

Influence of deer horn on serum cholesterol level as well as growth rate of experimental cholesterol-fed rabbit were observed. The cholesterol level rose progressively in all cholesterol-fed rabbit and only after 17th day of experiment, cholesterol-level in animal treated with deer horn significantly increased at much lower rate than control group. Above results suggested that deer horn might decrease the abnormally elevated serum cholesterol.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.12 no.1
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• pp.25-32
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• 2008

A pin fin is optimized based on the increasing rate of heat loss by using a two-dimensional analytic method. The optimum heat loss, corresponding optimum thermal resistance and fin length are presented as a function of the fin base thickness, convection characteristic numbers ratio, fin outer radius and ambient convection characteristic number. One of the results shows that both the optimum heat loss and fin length decrease linearly whereas the optimum thermal resistance increases very slightly with increase of the fin base thickness.

• Journal of the Korean Ceramic Society
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• v.15 no.1
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• pp.21-27
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• 1978

Hadong Kaolin (Halloysite) was granulated cylindrically and treated with 1N aqueous sodium hydroxide solution for 6-48 hrs at 60-10$0^{\circ}C$. The crystalling structure of surface of the products was studied by X-ray powder diffraction method. The reaction rate of halloysite to sodium A zeolite showed a gradual decrease from surface to inner layer. At the surface layer, the reaction mechanism was observed as first order consecutive reaction as follows: halloysitelongrightarrowamorphous aluminosilicatelongrightarrowsodium A zeolitelongrightarrowhydroxysodalite By applying the above reaction mechanism, the rate constants and activation energies was measured.

• Journal of Korean Institute of Industrial Engineers
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• v.6 no.1
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• pp.1-7
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• 1980

An exact solution technique for M/M/s multi-server demanding queue is introduced, and a general form of the curves representing service rates of the system is presented. As the number of customers in the system increases, the service rate is shown to increase initially, then decrease, and finally converge to a certain value. It is also shown that this phenomenon persists regardless of the numbers of servers and customer types.

• YAKHAK HOEJI
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• v.5 no.1
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• pp.6-9
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• 1960

Influences of deer horn on serum cholesterol level as well as growth rate of experimental cholesterol-fed rabbit were observed. The cholesterol level rose progressively in all cholesterol-fed rabbit and only after 17th day of experiment, cholesterol-level in animal treated with deer horn significantly increased at much lower rate than control group. Above results suggested that deer horn might decrease the abnormally elevated serum cholesterol.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.3166-3168
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• 2000

This paper proposed variable threshold dual rate ADPCM coding method which is modified from the standard ADPCM of ITU G.726 for speech quality improvement. The speech quality of variable threshold dual rate ADPCM is better than single rate ADPCM at noisy environment without increasing the complexity by using ZCR(Zero Crossing Rate). In this case, ZCR is used to divide input signal samples into two categories(noisy & speech). The samples with higher ZCR is categorized as the noisy region and the samples with lower ZCR is categorized as the speech region. Noisy region uses higher threshold value to be compressed by 16Kbps for reduced bit rates and the speech region uses lower threshold value to be compressed by 40Kbps for improved speech quality. Comparing with the conventional ADPCM, which adapts the fixed coding rate. the proposed variable threshold dual rate ADPCM coding method improves noise character without increasing the bit rate. For real time applications, ZCR calculation was considered as a simple method to obtain the background noise information for preprocess of speech analysis such as FFT and the experiment showed that the simple calculation of ZCR can be used without complexity increase. Dual rate ADPCM can decrease the amount of transferred data efficiently without increasing complexity nor reducing speech quality. Therefore result of this paper can be applied for real-time speech application such as the internet phone or VoIP.

• KDI Journal of Economic Policy
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• v.26 no.1
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• pp.105-140
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• 2004

Korea is entering the class of aging population nations. This paper investigates the extent demographic factors and the aging population affect the saving rate, using an extended life-cycle/permanent-income hypothesis on saving. The results of the tests with Korean household survey data from 1977 to 2002 reveal that real saving rates increase when the duration of lifetime and per household real disposable income rise, and decrease when the growth rate of income and net worth-to-GDP ratio rises. The growth rate of per household real disposable income has negative effects, suggesting that households calculate their life cycle income in a forward looking manner. The elasticities with respect to a change in the lifetime horizon and the growth rate of per household income are 0.58 and -0.03, respectively. A one percent rise in the net worth to GDP ratio reduces the saving rate by 0.3 percent. A one percent rise in per household income increases it by 0.33 percent. The younger-age and the elder-age dependency ratios have insignificant effects on the household saving rate behavior. When Korean life expectancy rises, the private saving rate declines modestly and the government saving rate declines substantially. The economy's real net saving rate declines from 33 percent in 2002 to 30 percent by the year 2030.

• Journal of Korea Society of Digital Industry and Information Management
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• v.6 no.1
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• pp.69-81
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• 2010

Physical manifestations of aging due to the lack of exercise include the slowing down of motor learning, cardiopulmonary degradation, and the increasing difficulty to adapt to the environment. Aging is manifested with the lack of aerobic exercise work, decrease in muscular endurance, decline in skeletal and muscular strength, flexibility and agility, and the decrease in reaction speed and balance. Added to those are aging-related physiological changes, including the reduction of muscle bulk, increased body fat, decrease in total body water and basic metabolic rate as activities are reduced, and a decrease in cell and Lean Body Mass (LBM). These changes are known to cause problems. Interest and participation in appropriate physical activities among the elderly is needed to help them increase stamina, avoid diseases, maintain a clear intellect, and basically enable the elderly to live their daily lives as easy as possible. Therefore, physical activities are necessary for the elderly to enhance health-related factors. Special exercises should be performed for the enhancement of muscle function, muscle endurance, flexibility, agility, and balance. An accurate measurement of cardio-respiratory endurance and stamina through basic physical and cognitive characteristics of older adults is also required to ensure safety. Also, the development of a more scientific resistance exercise prescription system for the elderly is desperately needed.

• Korean Journal of Pharmacognosy
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• v.18 no.4
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• pp.254-264
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• 1987

This study was attempted to investigate the effect of Ganoderma lucidum (Young-Jii) extract on the activities of GPT GOT Al. P LDH and the level of total bilirubin and total cholesterol in serum of $CCl_4$-intoxicated rats, and on the level of total lipids triglyceride phospholipids and total cholesterol in the serum of experimentally induced hyperlipemic rats, and on the effect of body and liver weight in rats. The results were shown as follows; In $CCl_4$-intoxicated rats, the extract showed a significant decrease in the activities of GPT and Al.P, a slight decrease in the activity of GOT and LDH; The level of total bilirubin was slightly affected, but significantly decreased at a dose as high as 500 mg/kg; the level of total cholesterol was increased dose dependently. In hyperlipemic rats, the extract caused a significant decrease in the level of total lipids and triglyceride and the rate of decrease was more pronounced with repeated treatments for 10 days; the level of phospholipids and total cholesterol were slightly decreased with repeated treatment of the extract at a dose of 300 mg/kg for 10 days; A significant body weight gain was shown with the treatment of the extract.