• Journal of Nutrition and Health
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• 제20권6호
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• pp.422-431
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• 1987

Dietary habits and serum lipid composition of 80 hospitalized patients with cerebrovascular disease (CVD) were compared to those of normal subjects. CVD patients were significantly higher in BP, serum cholesterol and triglyceride levels and low4r in HDL-choelsterol which resulted in the higher ratio of serum chol/HDL-chol than normal. Patients were also lower in the relative amount of HDL fraction by electrophoresis but were higher in LDL fraction and the ratio of LDL/HDL . In Korean, the high levels of serum chol, TG and LDL with low level of HDL as well as high BP could be one of the important causing factors of CVD. However, dietary habits of patients were not significantly different from those of normal . There is a possibility that patients might have controlled their dietary habits after they realized the severeness of disease.

• 산업경영시스템학회지
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• 제41권2호
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• pp.117-132
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• 2018

There always exist nonzero inspection errors whether inspectors are humans or automatic inspection machines. Inspection errors can be categorized by two types, type I error and type II error, and they can be regarded as either a constant or a random variable. Under the assumption that two types of random inspection errors are distributed with the "uniform" distribution on a half-open interval starting from zero, it was proved that inspectors overestimate any given fraction defective with the probability more than 50%, if and only if the given fraction defective is smaller than a critical value, which depends upon only the ratio of a type II error over a type I error. In addition, it was also proved that the probability of overestimation approaches one hundred percent as a given fraction defective approaches zero. If these critical phenomena hold true for any error distribution, then it might have great economic impact on commercial inspection plans due to the unfair overestimation and the recent trend of decreasing fraction defectives in industry. In this paper, we deal with the same overestimation problem, but assume a "symmetrical triangular" distribution expecting better results since our triangular distribution is closer to a normal distribution than the uniform distribution. It turns out that the overestimation phenomenon still holds true even for the triangular error distribution.

• 대한기계학회논문집A
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• 제24권1호
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• pp.250-258
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• 2000

The reinforcing effects of ductile short-fiber reinforced brittle matrix composites are studied by, measuring flexural strength, fracture toughness and impact energy as functions of fiber volume fraction and length. The parameters of fracture mechanics, K and J are applied to assess fracture toughness and bridging stress. It is found that fracture toughness is greatly, influenced by the bridging stress ill which fiber pull-out is occur. For the reinforcing effects as functions of fiber volume fraction($V_f$ = 1, 2, 3 %) and length(L = 3, 6. 10cm), the flexural strength is maximum at $V_f$ = 1% and both fracture toughness.

• Journal of Applied Biological Chemistry
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• 제44권2호
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• pp.77-83
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• 2001

For defining the possibilities of the commercial mass liquid culture of Cordyceps sinensis, the pharmacological activities of mycelia were analyzed. The mycelium of C. sinensis consists of carbohydrate (5.1%) and fat (1.3%), and contains a low content of protein (0.7%) and ash (0.5%), and 92.4% moisture. The molecular sugar ratio of carbohydrate was composed mainly of glucose, mannose (1.0 : 0.9), in addition a small amount of galactose and arabinose (0.2 : 0.1). The cellular materials of mycelia were fractionated into ethylacetate (EA), MeOH (M) and hot-water extract fraction (HW). HW fraction showed the most potent intestinal immune system modulating activity, anti-coagulant activity, and anti-complementary activity, and M fraction had the inhibition activity of radical generation as effective as genistine. These results reveal that the mycelium of liquid cultured C. sinensis showed pharmacological activities and could be used for commercial purpose.

• Journal of Welding and Joining
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• 제16권2호
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• pp.64-72
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• 1998

This study aims a investigating the effect of volume fraction of chromium carbide phase(VFC) of hardfaced iron/chromium alloys on fracture toughness. The alloys were deposited twice on a mild steel plate using self-shielding flux cored arc welding process. In order to examine VFC effect, different VFC (0.28∼0.62) were employed by changing the Cr and C content, while the ratio of Cr/C was fixed in the range of 5.7∼6.6. Fracture toughness was constant as increasing VFC because fracture surface was developed in the eutectic phase which was growing parallel with introduced sharp notch in the hypoeutectic alloys, but fracture toughness did not decreased in spite of increasing volume fraction of coarse primary chromium carbide phase which was easily craced at the low stress because the growth direction of chromium carbide phase were more irregular as increasing VFC in the hypereutectic alloys.

• 한국가시화정보학회지
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• 제15권1호
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• pp.11-18
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• 2017

A two-phase flow observed in a heat exchanger or nuclear power generation often has a profound effect on undesirable noise or flow characteristics. Void fraction, which refers to the ratio of gas (or liquid) to the total fluid, affects heat transfer coefficient, vibration and so forth. In other words, void fraction is one of most important parameters in two-phase flow since it contributes to comprehend the characteristics of two-phase flow. We developed a two-phase flow visualization system to measure cross-sectional and volumetric void fractions by using quick closing valves and image processing software. With this system, we could observe the plug, slug, and stratified flow patterns of two-phase flow and measure a myriad of void fractions. As a consequence of the experiment, we found that the estimated void fractions were largely coincident with the predictive values by Chisholm model.

• 소성∙가공
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• 제24권4호
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• pp.241-247
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• 2015

In order to prevent shape defects such as fluting and stretcher strains during press forming of aged low carbon steel sheets, roller leveling conditions for reducing yield point elongation were studied. Yield point elongations of leveled sheets were determined as a function of leveling, which is defined as the plastic fraction or the ratio of plastically deformed part in sheet thickness section to the whole thickness of the sheet. By adjusting this plastic fraction during leveling to more than 78%, yield point elongation in the leveled sheets was reduced so no fluting occurred during subsequent tangential bending. Stretcher strains can be avoided by leveling the sheet to an 84% plastic fraction condition.

• 한국수학교육학회지시리즈A:수학교육
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• 제44권1호
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• pp.67-85
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• 2005

This study investigated elementary teachers' subject matter knowledge and pedagogical content knowledge of fractions. The subject for data collection were 12 in-service elementary teachers and data were collected through written test problems. The finding imply that most elementary teachers understand fraction construct as part-whole, show low level of understanding of operator, ratio, and measurement constructions and word problem posing, using models, and developing the algorithms to divide fractions. The research results indicates that experienced teachers possess poor knowledge of fractions against novice teachers.

• 한국연소학회지
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• 제13권4호
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• pp.26-36
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• 2008

Experimental study is conducted to identify the existence of a shrinking flame disk and to clarify its flame characteristics through the inspection of critical mole fraction at flame extinction and edge flame oscillation at low strain rate flames. Experiments are made as varying global strain rate, velocity ratio, and burner distance. The transition from a shrinking flame disk to a flame hole is verified through gradient measurements of maximum flame temperature. The evidence of edge flame oscillation in flame disk is also provided through numerical simulation in microgravity. It is found at low strain rate flame disks in normal gravity that buoyancy effects are importantly contributing to lateral heat loss to burner rim, and is proven through critical mole fraction at flame extinction, edge flame oscillation, and measurements of flame temperature gradient along flame disk surface.

• 한국균학회지
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• 제10권3호
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• pp.111-117
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• 1982

The carpophores of Cryptoporus volvatus collected in Gyeong-gi Province of Korea were extracted with water and a protein-polysaccharide fraction was obtained after dialysis and lyophilization. The antitumor activity of this fraction was tested against sarcoma 180 implanted in A-strain mice. The tumor inhibition ratio was 80.4% in case of the high dose group (50mg/kg, ip, 10 days) and 70.3% in the low dose group (20mg/kg, ip, 10 days). The protein­polysaccharide fraction was chemically analyzed and was found to be a complex of a protein which was 18.2% of the fraction when determined by Lowry-Folin method, and a polysaccharide which was 55.3% of ther fraction when determined by Anthrone method. Their subunits were identified as four monosaccharides and 18 amino acids by gas-liquid chromatography and amino acid autoanalysis.