• Journal of the Korean Wood Science and Technology
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• 제23권3호
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• pp.58-65
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• 1995

The possibilities of the estimation of the moisture content(MC) for sitka-spruce (Picea sitchensis Carr.) by measuring density have been investigated. The method is based on the relationships between the wood density and moisture content of wood expressed by Equations (8)~(9). The purpose of this study is examining the estimation of the moisture content of wood by density and the variation of moisture content with annual ring width of wood. The following conclusions were obtained; 1. This method is very convenience because of the average moisture content of wood can be obtained by a simple estimation. This estimation can be made from the easy measurement of the weight and volume of wood. 2. Coefficient of determination between the experimental MCs and theoretical MCs which is calculated by the oven-dry densities of each specimens and Equations (8), (9) is 0.98. This Correlation is very remarkable. Therefore the model Equations on the estimation of moisture content by wood density was available. 3. Relationship between experimental MCs and theoretical MCs which is estimated by average oven-dry density of total specimens showed positive correlation(Fig.2). But from the Fig.4. we can concluded that the number of specimens is two groups. This phenomenon is considered that the variation of MC by the annual ring width from the specimens' observations. Consequently, the MCs of wood by density, is likely to be successful method. can be estimate using by the average oven-dry densities divided with the annual ring widths of wood.

• 대한영양사협회학술지
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• 제12권1호
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• pp.10-17
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• 2006

The purpose of this study was to examine the correlation between nutrient intakes and bone mineral density in female university students. A total 27 female university students were measured the anthropometric characteristics, dietary intake and the bone mineral density of carpus using DEXA. The average age, height, weight, % body fat, WHR, and BMI of the subjects were 22.7 years, 161.5 cm, 57.0 kg, 29.9%, 0.8, 21.8 kg/$m^2$, respectively. Bone mineral density of ultradis and distal carpus as T-value were -1.5 and -0.4, respectively. The daily energy intake of the subjects was 1589.0kcal. And the intakes of energy, calcium, iron, zinc, vitamin $B_2$, and folic acid did not meet the Korean RDAs. The daily total food intake of the subjects was 1011.0g and food intake from cereals and vegetables was high. The major food groups of mineral intake were vegetables/cereals/milks/fishes for calcium, cereals/meat/vegetables/fishes for phosphorus, cereals/vegetables/meats for iron, seasonings/vegetables/cereals for sodium, vegetables/cereals/seasonings for potassium, and cereals/meats for zinc. The body weight and body mass index were significantly positive correlated to the bone mineral density of average carpus, respectively. The intakes of animal calcium and vitamin $B_2$ were significantly negative correlated to the bone mineral density of average carpus, respectively. In conclusion, bone mineral density in carpus and nutrient intakes of some female university students were low. Therefore, health management and the study on relation between bone mineral density in various site and long-term intakes of nutrients in many subjects are required.

• Journal of Nutrition and Health
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• 제37권4호
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• pp.291-301
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• 2004

We studied the effects of soy isoflavones supplementation with exercise on bone mineral density and the urinary excretion of deoxypyridinoline as an index of bone resorption rates in postmenopausal women. A total of 67 postmen-opausal women were assigned to Isoflavone (90 mg/day) or placebo groups. These group were further divided into groups that undergone a regular exercise or a rather sedentary state performing daily activity only. Four groups were Placebo-control group (n = 16), Placebo-exercise group (n = 16), Isoflavone-sedentary group (n = 19) and Isofla-vone-exercise group (n = 16). After the intervention, we compared anthropometric mesurement, dietary recall, bone mineral density (femoral neck, lumbar spine), urinary deoxypyridinoline between the groups and between the pre and post studies. There were no significant differences between the four groups in terms of average age, height, weight, period after menopause at the baseline. The average age of the subjects were 55.2 yrs, average height, weight, period after menopause were 154.7 cm, 59.3 kg, 5.58 yrs, respectively. After eight week intervention period, there were no significant differences between the four groups in bone mineral density, but urinary deoxypyridinoline excretion was significantly decreased both in Isoflavone-sedentary and Isoflavone-Exercise groups. These results suggest that Isofla-vone supplementation alone or with exercise may be preventive measures through the decrease of bone reabsorption rate in post-menopausal subjects. Whereas exercise alone did not appear to be an effective measure in bone loss with these subjects.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.97-99
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• 2003

Lineament density maps can be used for the quantitative evaluation of relationship between lineaments and groundwater occurrence. There are several kinds of lineament density maps including lineament length density, lineament cross-points density, and lineament counts density maps. This paper reports the usefulness of the representative elementary area (REA) concept for lineament analysis. This concept refers to the area size of the unit circle to calculate the lineament density factors distributed within the circle: length, counts and cross-points counts. The circle is a unit circle that calculates the sum of the lineament length, lineament counts and the number of cross-points within it. The REA is needed to obtain the best representative lineament density map prior to the analysis of relation between lineaments and groundwater well yield or other groundwater characteristics. A basic lineament map for the Yongsangang-Seomjingang watershed of Korea, drawn from aerial black-and-white photographs of 1/20, 000 scale was used for demonstrating the concept. From this study, the conclusions were as follows: (1) the REA concept can be efficiently applied to the lineament density analysis and mapping, (2) for whole Yongsangang-Seomjingang watershed which has 6, 502 lineaments with an average lineament length of 3.3 km, the lower limits of each REA used for drawing the three density maps were about 1.77 $\textrm{km}^2$ (r=750 m) for lineament length density, 7.07 $\textrm{km}^2$ (r=1, 500 m) for lineament counts density, and 4.91 $\textrm{km}^2$ (r=1, 250 m) for lineament cross-points density, respectively, (3) the lineament densities are inversely proportional to the size of REA, and the REA can be calculated with this inversely linear regression model, (4) if the average lineament density values for the whole study area are known, the most accurate density maps can be drawn using the REAs obtained from each linear regression model, and (5) but critical attention should be paid to draw lineament counts density and lineament cross-points density maps because.

• Journal of the Korean Statistical Society
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• 제29권3호
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• pp.307-313
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• 2000

Suppose we have a set of data X1, ···, Xn and employ kernel density estimator to estimate the marginal density of X. in this article bandwith selection problem for kernel density estimator is examined closely. In particular the Kullback-Leibler method (a bandwith selection methods based on average square error (ASE)) is considered.

• 한국ITS학회 논문지
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• 제17권5호
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• pp.77-87
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• 2018

교통밀도는 교통수요와 가장 직접적인 관계가 있으므로 거시적인 지표 중에서 가장 중요하다고 알려져 있으며(Traffic Engineering, 2004), 특정시각 주어진 거리 안의 존재하는 차량의 대수로 정의한다. 하지만, 밀도는 기상과 도로조건 및 비용 상의 문제로 인하여 현장에서 직접 수집이 어렵다. 이런 이유로 속도와 교통량보다 상대적으로 연구가 활발하게 이루어지지는 않아 수집방법에 관한 다양한 시도뿐만 아니라 측정된 값의 정확도에 관한 연구가 많이 부족하다. 이에 본 논문에서는 밀도를 측정할 수 있는 방법으로 여러 대의 카메라 영상을 정합(synthesis)하는 기술을 활용하였다. 이러한 밀도수집시스템으로 수집한 밀도를 정의에 기반한 참값으로 선정하고, 이 값을 전통적인 측정방법들로 산출한 밀도와 비교하였다. 비교결과, 관계식(fundamental equation)을 이용한 산출방법으로 산출한 밀도 값이 참값과 비교하여 RMSE(Root Mean Square Error)가 1.8-2.5로 가장 참값에 가깝다. 또한 향후 밀도를 직접 수집할 때 유의하여할 수집 간격 등의 간과하기 쉬운 이슈사항을 순간밀도와 평균밀도를 산출하여 알아보았다. 실험 사이트의 실제 교통상황은 LOS B임에도 불구하고, 초 당 순간밀도는 최대(16veh/km)에서 최소 2(veh/km)의 값이 다양하게 관측되어 교통상황의 판단이 어려웠다. 하지만 30초 간격으로 15분 평균밀도는 8.3-7.9(veh/km)로 정확하게 LOS B를 판단하였다.

• 복식문화연구
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• 제21권1호
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• pp.1-16
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• 2013

This study analyzed the characteristics of Korean traditional plain weave excavated from Sang-go period to Joseon Dynasty. To do this, this study classified the Korean traditional plain weave into fiber types(cotton, hemp & ramie, plain weaved silk), analyzed and compared the thickness, twist type of yarns and density by times. First, in characteristics of cotton, the average and maximum density of Joseon Dynasty were higher than those of Goryeo, twist type was mainly s-twist and the density of warp was higher than that of weft. Second, the maximum density of hemp & ramie was found in era of Three Kingdoms of Korea. In common characteristics of hemp & ramie, twist type was mainly s-twist(sometimes non-twist) to the Three Kingdoms of Korea and was changed into non-twist from the Goryeo. The density of warp was higher than that of weft in common. Generally, the average density of ramie was higher than that of hemp. Third, in the characteristics of plain weaved silk, twist type was mainly non-twist(sometimes s and z-twist) from Sang-go period to Joseon Dynasty. Warp-faced ribbed tabby was excavated in Goryeo, the average density of warp-faced ribbed tabby was higher than that of other fiber types plain weave. Generally, in all fiber types, the density of warp was higher than that of weft.

• 한국수산과학회지
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• 제29권5호
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• pp.663-676
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• 1996

한국 남동해역의 사질퇴적물의 물리적 성질 분포는 수심과 해류의 영향이 큰 것으로 나타났다. 수심 80m를 전후하여 잔류퇴적물인 muddy sand가 분포하고 모래함량은 $60\%$ 이상이며 수직적인 조직 및 물성변화는 별로 크지 않다. 표층퇴적물의 수평분포의 경우 평균입도는 한반도 동남해역과 대마도 중간선에서 가장 조립질로 나타나며 이와 완전히 일치하지는 않지만 전밀도의 경우도 중앙부가 높게 ($1.80g/cm^3$ 이상) 분포한다. 공극율과 함수율의 경우는 전밀도의 분포와 반대로 대한해협의 중심부 부근이 낮고 한반도나 대마도 쪽이 높은데 이는 평균입도 분포에서도 볼 수 있듯이 세립질 퇴적물 성분의 증가와 연관되어 있다. 또한 대마해류의 주 통로를 중심으로 북서-남동 방향으로 증가하는 양상이 뚜렷하게 관찰된다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권6호
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• pp.2986-2999
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• 2019

The uncertainties of the uncertain graph make the traditional definition and algorithms on mining dense graph for certain graph not applicable. The subgraph obtained by maximizing expected density from an uncertain graph always has many low edge-probability data, which makes it low reliable and low expected edge density. Based on the concept of ${\beta}$-subgraph, to overcome the low reliability of the densest subgraph, the concept of optimal ${\beta}$-subgraph is proposed. An efficient greedy algorithm is also developed to find the optimal ${\beta}$-subgraph. Simulation experiments of multiple sets of datasets show that the average edge-possibility of optimal ${\beta}$-subgraph is improved by nearly 40%, and the expected edge density reaches 0.9 on average. The parameter ${\beta}$ is scalable and applicable to multiple scenarios.

• Journal of Magnetics
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• 제22권2호
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• pp.203-213
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• 2017

Magnetically suspended control & sensitive gyroscope (MSCSG) is a novel type of gyroscope with the integration of attitude control and attitude angular measurement. To improve the precision and reduce the power consumption of Lorentz Force-type Magnetic Bearing (LFMB), the air gap flux density distribution of LFMB has been studied. The uniformity of air gap flux density is defined to qualify the uniform degree of the air gap flux density distribution. Considering the consumption, the average value of flux density is defined as well. Some optimal designs and analyses of LFMB are carried out by finite element simulation. The strength of the permanent magnet is taken into consideration during the machining process. To verify the design and simulation, a high-precision instrument is employed to measure the 3-dimensional magnetic flux density of LFMB. After measurement and calculation, the uniform degree of magnetic flux density distribution reaches 0.978 and the average value of the flux density is 0.482T. Experimental results show that the optimal design is effective and some useful advice can be obtained for further research.