• 한국농공학회:학술대회논문집
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• 한국농공학회 2001년도 학술발표회 발표논문집
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• pp.390-393
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• 2001

Mass balance and unit load of pollutants were investigated at paddy field area during irrigation periods in 1999 and 2000. The amounts of irrigation water during irrigation periods were 3,690mm in 1999 and 3,160mm in 2000. The concentration of surface outflow is not so high as that of irrigation because 44% of irrigation water discharge without entering the paddy plots. The unit loads of pollutants during irrigation periods were estimated 19.2kg/ha for T-N, 0.29kg/ha for T-P and 47.5kg/ha for COD.

• Journal of Nutrition and Health
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• 제26권8호
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• pp.933-941
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• 1993

The present study was carried out to investigate the effects of magnesium supplement levels and periods on lipid metabolism in male Sprague-Dawley rats given low protein and magnesium deficient diets. The effect of magnesium supplement levels and periods on lipid metabolism in rats given a low protein and magnesium deficient diet for 2 weeks were investigated. Serum total lipid and triglyceride contents were significantly lower in magnesium supplement group compared with magnesium deficient group. Serum HDL-cholesterol/total cholesterol ratio was significantly increased as magnesium supplement level was increased. Liver total lipid, triglyceride, total cholesterol and phospholipid contents were significantly lower in magnesium supplement group than those in magnesium deficient group. Serum ALP, GOT and GPT activities were significantly decreased in magnesium supplement group compared with magnesium deficient group. In summary, the effect of magnesium supplement on lipid metabolism and enzyme activities were significant and we can see that magnesium supplement level propered to be requirement level(400 mg/kg diet)in the other cases except serum lipid contents.

• 산업경영시스템학회지
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• 제32권3호
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• pp.71-77
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• 2009

Using the results of the expected busy periods for the dyadic Min(N, D) and Max(N, D) operating policies in a controllable M/G/1 queueing model, an important relation between them is derived. The derived relation represents the complementary property between two operating policies. This implies that it could be possible to obtained desired system characteristics for one of the two operating policies from the corresponding known system characteristics for the other policy. Then, upper and lower bounds of expected busy periods for both dyadic operating policies are also derived.

• 동아시아식생활학회지
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• 제19권2호
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• pp.169-179
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• 2009

The purpose of this study was to investigate nutritional component changes (chlorophylls, vitamin C, and minerals) in two Korean spinach cultivars (Cheongrok, Ddangddali) according to different growth periods, as well as differences in the components of three plant parts (leaves, stems, and roots). Chlorophyll, vitamin C, Na, and Hunter‘s color a/b values reached maximum levels in the spinach leaves after 35 days of planting, while these components did not significantly change in the stems and roots during the growth period. Chlorophyll and vitamin C contents were higher in the leaves than in thestems and roots. On the other hand, moisture content was higher in the stems than in the leaves and roots, and Fe content was highest in the roots. The vitamin C content of this fresh harvested spinach was 2.5 times higher compared to the existing data (Food Nutritive Value Table 2005).

• Wind and Structures
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• 제6권3호
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• pp.221-248
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• 2003

The design of high-rise building is often influenced by wind-induced motions such as accelerations and lateral deflections. Consequently, the building's structural stiffness and dynamic (vibration periods and damping) properties become important parameters in the determination of such motions. The approximate methods and empirical expressions used to quantify these parameters at the design phase tend to yield values significantly different from each other. In view of this, there is a need to examine how actual buildings in the field respond to dynamic wind loading in order to ascertain a more realistic model for the dynamic behavior of buildings. This paper describes the findings from full-scale measurements of the wind-induced response of typical high-rise buildings in Singapore, and recommends an empirical forecast model for periods of vibration of typical buildings in Singapore, an appropriate computer model for determining the periods of vibration, and appropriate expressions which relate the wind speed to accelerations in buildings based on wind tunnel force balance model test and field results.

• 대한인간공학회지
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• 제29권3호
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• pp.337-345
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• 2010

The purpose of this study was to investigate the effects of sleep/wake behavior for shiftwork in air traffic controllers (ATCs) using wrist actigraph for ten workers on a continuous full-day three-team three-shift system of forward rotation including on-duty and off-duty periods. The wrist actigraph data were recorded for three days (one shift cycle) for each subject. The mean activity counts during an on-duty period progressively increased from the night, the swing, to the morning shifts. The doze length during on-duty periods showed decreases in the morning and swing shifts as compared to the night shift. Total sleep time (TST) and sleep efficiency (SE) during off-duty periods increased in the morning-1 and swing-night shift compared to the morning-2 shift. Finally, I discussed the role of doze-taking during the burden on night shift ATCs.

• 산업경영시스템학회지
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• 제33권3호
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• pp.63-70
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• 2010

Based on the known results of the expected busy periods for the triadic Min (N, T, D) and Max (N, T, D) operating policies applied to a controllable M/G/1 queueing model, a relation between them is constructed. Such relation is represented in terms of the expected busy periods for the simple N, T and D, and the dyadic Min (N, T), Min (T, D) and Min (N, D) operating policies. Hence, if any system characteristics for one of the two triadic operating policies are known, unknown corresponding system characteristics for the other triadic operating policy could be obtained easily from the constructed relation.

• 농촌계획
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• 제10권2호
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• pp.25-34
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• 2004

The objectives of this study were to compare rural development of Korea and EU. According to its traits the peroids of rural development of Korea can be divided into low periods. According to its memberships and traits the periods of rural development of EU can be divided into low periods. There are many similarities between Korea and EU in agricultural situation and rural development. EU introduced multifunctionality of agriculture in 1980s and adopt strong policy to support that in 1990s. And EU made a effort sustainable rural development, integrated rural development and balanced regional development. Recently Korea not only maintain agricultural expanisionism but also pay attention to multifunctionality of agriculture. But rural development of Korea still in the stage of physical planning and agricultural expanisionism. So it leaves much room for improvement to rural development of Korea in rural development regulation, unifying theme, detail planning, integration among policies, balanced regional development, etc.

• 응용통계연구
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• 제21권3호
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• pp.485-495
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• 2008

A floating-strike lookback call option gives the holder the right to buy at the lowest price of the underlying asset. Similarly, a floating-strike lookback put option gives the holder the right to sell at the highest price. This paper will present explicit pricing formulas for these floating-strike lookback options with flexible monitoring periods. The monitoring periods of these options start at an arbitrary date and end at another arbitrary date before maturity. Sections 3 and 4 assume that the underlying assets pay no dividends. In contrast, Section 5 will derive explicit pricing formulas for these options when their underlying asset pays dividends continuously at a rate proportional to its price.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.201-201
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• 2000

Recently in the design of fuel tanks(launch vehicle, ship, automobile) which transport a large amount of liquid in the cargo holds, the structural damage due to liquid-sloshing becomes an important problem. The impact pressure from sloshing is most violent when the liquid motion of a partially filled tank is in resonance with the motion of a system. In this paper, the sloshing natural periods in liquid tanks are estimated for partially filled tanks with various geometries. In addition to, controlled for a launch vehicle with liquid sloshing effect by PD controller and sloshing filter The PD gain and sloshing filter parameter arc determined by optimal algorithm.