• Title/Summary/Keyword: related density

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The fluctuation of soil pathogenic microbes population in radish and chinese cabbage fields (무우 배추 포장내의 병원성 토양미생물 소장)

  • 이왕휴;소인영
    • Korean Journal of Microbiology
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    • v.21 no.1
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    • pp.7-14
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    • 1983
  • In order to study the effects of cropping system and fungicide (Dachigaren) on soil microbes, the seasonal fluctuations of soil microbes in the fields of radish and Chinese cabbage including soil pH, Soil moisture content and soil temperature were investigated on every 15 day interval from the begining of March to late October in 1981. The population of total fungus peaked at the begining of July, while that of total bacteria, at the begining of August. They were affected by soil temperature, however pathogenic microbes seemed to be more related with host plants than the soil temperature, because pathogens showed high density through the whole cultivation period. The pathogenic microbes showed the density of order ; Xanthomonas, Erwinia, Pseudomonas, Agrobacterium and Corynebacterium. Xanthomonas, Erwinia and Pseudomonas, which induced radish and Chinese cabbage diseases were higher than Agrobacterium and Corynebacterium in population densigy. Bacterial soft rot occured at the density of Erwinia $5.9{\sim}6.6{\times}10^5/dry$ soil 1 gram. The density of microbes on continuous fields were higher than that of rotating fields, but there were no significant difference between treated fungicide plot and non treated in the density of microbes, also no difference between Chinese cabbage and radish growing fields.

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The effect of target power density on physical and structural properties of amorphous carbon films prepared by CFUBM sputtering (비대칭 마그네트론 스퍼터링으로 합성된 비정질 탄소박막의 물리적, 구조적 특성에서 타겟 파워 밀도의 영향)

  • Lee, Jae-Hee;Park, Yong-Seob;Park, Jae-Wook;Hong, Byung-You
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.366-366
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    • 2008
  • Amorphous carbon (a-C) is an interesting materials and its characteristics can be varied by tuning it $sp^3$ fractions. The $sp^3$ fraction in a-C films depends on the kinetic energy of the deposited carbon ions. In this work, a-C films was synthesized on Si(100) and glass substrates at room temperature by closed-field unbalanced magnetron (CFUBM) sputtering with the increase of graphite target power density. The structural and physical properties of films were investigated by using Raman spectroscopy, X-ray photoelectron spectrometer (XPS), nano- indentation, atomic force microscope (AFM) and contact-angle measurement. We obtained the good tribological properties, such as high hardness up to 26 GPa., friction coefficient lower than 0.1 and the smooth surface (rms roughness: 0.12 nm). The increase of the physical properties with the increase of target power density are related to the increase of nano-clusters in the carbon network. Also, these results might be due to the increase of the subplantation and resputtering by the increase of ions density in the plasma.

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A study on the correlation between exhibition space configurations and visitors' viewing behavior in museums - From a Viewpoint of Visitor Density in Public History Museums in Seoul Metropolitan Area of Korea - (뮤지엄 전시공간구조와 관람행태의 상관관계에 관한 연구 - 한국의 수도권 공립 역사계 뮤지엄의 관람밀도의 측면에서 -)

  • Kim, Mi Hyun;Moon, Jung Mook
    • Korean Institute of Interior Design Journal
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    • v.21 no.5
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    • pp.343-354
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    • 2012
  • Museums in Korea have experienced continuing quantitative growth since the late Choson Dynasty. However, a careful examination of visitors' viewing behavior has not been properly performed. Accordingly, social education for visitors in museums is not properly conducted despite the vast amount of information that museums possess. Given these circumstances, this study which focuses on the factors that influence visitors' behavior in museums intends to examine the effects that the configuration of exhibition space and the resulting visitor circulation patterns have on visitors' behavior with regard to visitor density. From this perspective, and considering five public historical museums within the seoul metropolitan area of korea, a correlation analysis has been conducted based upon quantitative analysis related to the configuration of exhibition space and visitors' observed viewing behaviors. The result of our study is that the configuration of exhibition space influences the patterns of visitor circulation, distribution of space, and the subsequent state of visitor density. Accordingly, the effects of visitor density on the viewing speed and other viewing behaviors could be identified. Based on these findings, the configurational differences in exhibition spaces were identified as one of the key factors that influence visitors' viewing behaviors.

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Modeling the Relationship between Process Parameters and Bulk Density of Barium Titanates

  • Park, Sang Eun;Kim, Hong In;Kim, Jeoung Han;Reddy, N.S.
    • Journal of Powder Materials
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    • v.26 no.5
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    • pp.369-374
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    • 2019
  • The properties of powder metallurgy products are related to their densities. In the present work, we demonstrate a method to apply artificial neural networks (ANNs) trained on experimental data to predict the bulk density of barium titanates. The density is modeled as a function of pressure, press rate, heating rate, sintering temperature, and soaking time using the ANN method. The model predictions with the training and testing data result in a high coefficient of correlation (R2 = 0.95 and Pearson's r = 0.97) and low average error. Moreover, a graphical user interface for the model is developed on the basis of the transformed weights of the optimally trained model. It facilitates the prediction of an infinite combination of process parameters with reasonable accuracy. Sensitivity analysis performed on the ANN model aids the identification of the impact of process parameters on the density of barium titanates.

Effects of element composition in soil samples on the efficiencies of gamma energy peaks evaluated by the MCNP5 code

  • Ba, Vu Ngoc;Thien, Bui Ngoc;Loan, Truong Thi Hong
    • Nuclear Engineering and Technology
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    • v.53 no.1
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    • pp.337-343
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    • 2021
  • In this work, self-absorption correction factor related to the variation of the composition and the density of soil samples were evaluated using the p-type HPGe detector. The validated MCNP5 simulation model of this detector was used to evaluate its Full Energy Peak Efficiency (FEPE) under the variation of the composition and the density of the analysed samples. The results indicates that FEPE calculation of low gamma ray is affected by the composition and the density of soil samples. The self-absorption correction factors for different gamma-ray energies which was fitted as a function of FEPEs via density and energy and fitting parameters as polynomial function for the logarithm neper of gamma ray energy help to calculate quickly the detection efficiency of detector. Factor Analysis for the influence of the element composition in analysed samples on the FEPE indicates the FEPE distribution changes from non-metal to metal groups when the gamma ray energy increases from 92 keV to 238 keV. At energies above 238 keV, the FEPE primarily depends only on the metal elements and is significantly affected by aluminium and silicon composition in soil samples.

Bone Density and Related Factors of University Students in the Seoul Area (서울지역 대학신입생의 골밀도에 미치는 영향요인에 관한 연구)

  • Chung, Nam-Yong;Choi, Soon-Nam
    • Korean journal of food and cookery science
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    • v.20 no.5
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    • pp.468-479
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    • 2004
  • This study was conducted to investigate factors affecting the bone density of university students in the Seoul area. Data for food habits, and dietary and health-related behavior was obtained by self-administered questionnaires. BQI (bone quality index) of the subjects was measured by a Quantitative Ultrasound (QUS). The results are summarized as follows. The average height, weight, BMI and osteopenia percentage were 175.4cm, 69.3kg, 22.5 and 15.6% for male students, and 161.5cm, 55.9kg, 21.7 and 34.1%, for female students, respectively. The mean BQI of the subjects was 110.25 (range 60.7 ~ 176.8) in male students and 90.64 (range 52.9 ~ 137.5) in female students. Height and weight were significantly related with BQI in the female group but the relationship with BMI was not significantly related with bone density in either group. BQI was positively affected by nutrition supplement in the male student group. One-side eating, diet, and intake of milk and instant food were not significantly related with BQI in males or females. The results of this study revealed that desirable food habits, dietary behavior and health-related lifestyle may have a beneficial effect on bone density. There should be established a practically and systematically organized nutritional education on optimum body weight, good eating habits, weight bearing exercise and intakes of good quality nutrient for higher bone density level.

Bone Density and Related Factors of Vegetarian and Non-vegetarian University Students in Seoul Area (서울지역 채식.비채식 대학생의 골밀도에 미치는 영향요인에 관한 연구)

  • Chung, Nam-Yong;Choi, Soon-Nam
    • Journal of the Korean Society of Food Culture
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    • v.21 no.1
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    • pp.86-98
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    • 2006
  • This study was conducted to investigate factors affecting bone density of food and nutrition vegetarian and non-vegetarian university students in Seoul area. Data for food habits, dietary and health-related behaviors were obtained by self administered questionnaires. BQI(bone quality index) of the subjects was measured by an Quantitative Ultrasound (QUS). The results are summarized as follows: The average height, weight, BMI and osteopenia percentage of the vegetarian and non-vegetarian male and female student were 172.61cm, 62.42kg, 20.98 and 24.2%; 175.38cm, 72.52kg, 23.71 and 16.7%; 160.47cm, 55.76kg, 21.66 and 55.9%; 161.77cm, 56.34kg, 21.53 and 37.6%, respectively. The BQI of the subjects were 101.73 and 107.43 in male student group, and 84.15, 89.64 in female student group, respectively. The BQI, Z-score value of bone density was significantly different in female group. Weight and BMI were positively related with BQI in male and female group. BQI was positively affected by nutrition supplement and negatively affected by seafood in vegetarian male student group. In vegetarian female student group, amount of meal was positively related with BQI and meal regularity was negatively related BQI. The result of this study revealed that the desirable food habits, dietary behaviors and health-related lifestyles may have a beneficial effect on bone density. They should have practically and systematically organized nutritional education on optimum body weight, good eating habits, weight bearing exercise and intakes of good quality nutrient for higher bone density level.

The Relationship Between Bone mineral Density and The Environmental Factors in Korean Pubescent Girls (한국 사춘기 소녀들의 골밀도와 환경요인들과의 관계(II))

  • 최미자
    • Journal of the East Asian Society of Dietary Life
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    • v.5 no.1
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    • pp.41-51
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    • 1995
  • Bone mass accretion during puberty appears to be critical in the development of peak bone mass. Although bone density of females in Korea has been studied, only a few studies have related bone mass with anthropometric patterns or puberty in the pubescent girls. This study was conducted as part of a study of major determinants of bone development during puberty. Subjects were aged 14∼16 yr(mean 14.97), and had no history of disorders or dedication use likely to influence bone or calcium metabolism. Bone mineral density and content were measured by dual energy X-ray absorptiometry using a Lunar DPX+Scanner (Lunar Madison, WI). Also, total body fat, and total lean body mass were assessed using a Lunar DPX dual-energy X-ray absorptiometer, Pubertal status was assessed according to the Marshall and Tanner guidelines. Serum levels of osteocalcin was measured by RIA using a commercial kit assay. Skinfold measurements were taken with a skinfold caliper(Lange Caliper, USA). Data were analyzed using the regression and GLM procedure of the statistical package SAS. The results indicated that the observed means for lumbar spine BMD and femoral BMD correspond to approximately 91% and 96% of the means for young adult females, respec tively. All subjects were menarchal, with the majority being in the middle to end stages of pubertal development. Total body BMD was positively related to fat mass(P<0.001), lean body mass and time since menarche, and negatively related to urine pyridinoline, serum alkaline phosphatase and osteocalcin. The data indicate that girls who reported lower age for menarche had significantly higher bone densities than girls who reported higher age for menarche. Attaining peak skeletal bone mass during puberty may reduce the incidence of osteoporosis in later life. this finding suggests that early menarche may augment peak bone mass, influencing the extent of bone loss later in adulthood. The results suggest that good nutrition in childhood appears to be needed not for growth and development, but possibly also to assure an optimal peak of bone mass and thus greater latitude for the maintenance or skeletal integrity in the face of bone losses. Troeps skinfold thickness was a better predictor of total BMD and total BMC than was any other skinfold thickness. The study did not find a relationship between total BMD and body fat %, but total fat was significantly positively related to total BMD(r=0.49) and total BMC(r=0.60). It supports earlier report that there was a significant correlation between TBMD and body weight. Conclusively, total fat, lean body mass and pubertal development could influence BMD in pubescent girls. Clearly, longitudinal studies are required to assess the effect of puberty on peak bone mass, and to define further the potential determinants of peak bone mass.

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Correlations among Shearing Force, Morphological Characteristic, Chemical Composition, and In situ Digestibility of Alfalfa (Medicago sativa L) Stem

  • Liu, L.;Yang, Z.B.;Yang, W.R.;Jiang, S.Z.;Zhang, G.G.
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.4
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    • pp.520-527
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    • 2009
  • Alfalfa (Medicago sativa L) is a high-quality forage for ruminants and the main stem is the dominant morphological component contributing to the forage nutritive value in mature alfalfa forage. Shearing force, a fracturing property of plant stem, is an important indictor of forage value. The objectives of this study were to investigate the effects of morphological characteristic on shearing force, the relationship between shearing force and chemical composition, and the relationship between shearing force and in situ digestibility of alfalfa stem. The results showed that linear density (weight per unit length of stem) was more important than chemical composition in affecting shearing force. There was a positive relationship between lignin content and shearing force (r = 0.78). Correlations were not found between shearing force and other chemical components such as neutral detergent fiber (NDF), acid detergent fiber (ADF), cellulose and hemicelluloses. In situ digestibility (of dry matter and NDF) was related to shearing force. A negative correlation was found between shearing force and dry matter (DM) digestibility (r = -0.70), and there was also a negative correlation between shearing force and NDF digestibility (r = -0.87). When shearing force was standardized for stem diameter or stem linear density, the relationship between shearing force and digestibility was consistent regardless of stem diameter and stem linear density. Shearing force was significantly correlated with lignin content and in situ digestibility (of DM and NDF), and was a more direct indicator for estimating forage nutritive value related to animal performance, so it can be used to predict the forage value of alfalfa.

A Study on the Correlation of Fungiform Papillae (Taste Bud) and Eating Behavior of Children and Adolescents (소아 및 청소년에서 버섯 유두 개수로 산출한 설 미뢰 밀도와 식습관의 상관성 연구)

  • Choi, Hyeon;Bae, Sun-Jae;Lee, Sang-Yong;Lee, Eun-Hye
    • The Journal of Pediatrics of Korean Medicine
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    • v.24 no.1
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    • pp.1-8
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    • 2010
  • Objectives This study is to find out how fungiform papillae count, which represents the density of taste buds, is related to eating behavior of children and adolescents. Methods The authors measured fungiform papillae count, height, and weight of 50 healthy children aged from 2 to 15. To evaluate the severity of anorexia, parents of the subjects answered modified version of Korean Children's Eating Behaviour Questionnaire (K-CEBQ). Children with weight of less than 50th percentile were assigned to low-weight group, while the others to high-weight group. Pearson's correlation test was conducted in order to evaluate the relationship between modified K-CEBQ score and fungiform papillae count. Results Low-weight children scored $29.8{\pm}9.1$, while high-weight children scored $24.5{\pm}7.1$. (p<0.05) on modified K-CEBQ Pearson's correlation coefficient between modified K-CEBQ score and fungiform papillae count was 0.503 (p<0.05) in low-weight group, 0.260 in high-weight group, and 0.339 (p<0.05) in total. However, there were no statistical significance in correlations between modified K-CEBQ score and percentile of weight, height, or BMI. Conclusions Severity of anorexia was correlated to the density of taste buds, especially in children who weighed less than average. The analysis on each single question indicated that children with high taste bud density had poor appetite not because of their inadequate digestive function, but because of their fastidious eating habit. Further study should be focused on finding out which specific aspect of appetite is related to the taste bud density.