• Title/Summary/Keyword: density index

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A Study on the Factors Affecting Bone Mineral Density in Adult Women - Based on the Mothers of Elementary School Students- (일부 초등학생의 어머니를 대상으로 한 성인 여성의 골밀도에 영향을 미치는 요인에 관한 연구)

  • 김기랑
    • Journal of Nutrition and Health
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    • v.33 no.3
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    • pp.241-249
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    • 2000
  • The bone mineral density(vertebrae Ll-4, femoral neck, Ward's triangle and trochanter) of 160 healthy adult women aged 29-45 was measured and general characteristics, anthropomentric measurements, and dietary intake were also studied to determine the main factors affecting the bone mineral density(BMD) of adult women. The nutrient intake of the subjects was adequate to RDA level except energy, Ca, Fe, and vit A. The BMD of vertebrae L24 showed significant positive association with nutrient intake such as animal protein, P, Ca(animal) and Fe(animal). The BMD of the femoral neck correlated significantly with anthropometric measurements such as height, weight, waist circumference, hip circumference, body fat and body mass index. The BMD of both sites(vertebrae L24 and femoral neck) were significantly related to vertebrae L24 was daily Ca intake and that of femoral neck was daily energy expenditure. In conclusion, adequate nutrient intake, especially protein, P, Ca and Fe as well as increases in physical activity were suggested to prevent the loss of bone mineral density in adult women.

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Effectiveness of Flashing Light for Increasing Photosynthetic Efficiency of Microalgal Cultures over a Critical Cell Density

  • Park, Kyong-Hee;Lee, Choul-Gyun
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.6 no.3
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    • pp.189-193
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    • 2001
  • Critical cell density (CCD), the maximum cell concentration without mutual shading in algal cultures, can be used as a new operating parameter for high-density algal cultures and for the application of the flashing light effect on illuminated algal cultures. CCD is a function of average cell volume and light illumination area. The CCD is thus proposed as an index of estimation of mutual shading in algal cultures. Where cell densities are below the CCD, all the cells in photobioreactors can undergo photosysnthesis at their maximum rate. At cell densities over CCD, mutual shading will occur and some cells in the illumination chamber cannot grow photoautotrophically. When the cell concentration is higher than the CCD, specific oxygen production rates under flashing light were higher than those under continuous light. The CCD was found to be a useful engineering parameter for the application of flashing light, particularly in high-density algal cultures.

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Smoke density comparison for composite and single materials of train seat (철도차량 시트재료의 개별 및 조립체 시험에 대한 연기특성 비교)

  • Lee, Eun-Kyoung;Lee, Duck-Hee;Cho, Hee-Ki;Lee, Cheul-Kyu;Jung, Woo-Sungg
    • Proceedings of the KSR Conference
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    • 2006.11b
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    • pp.196-201
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    • 2006
  • Due to the damage which is caused by with the smoke, in the analysis statistics of a fire accident smoke is becoming the important evaluation index of fire quality. We must follow the procedures to use interior material for railway car as stated the Safety regulation for the urban railway car. In this study, we compared the Smoke Density of the train seat by test between Cone-Calorimeter and Smoke Density-Chamber. The results showed that the smoke density by test between Cone-Calorimeter and Smoke Density-Chamber is visible a similar tendency.

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Changes of Plant Cell Size Index by Culture Conditions (배양 조건에 따른 식물세포 크기 지수의 변화)

  • 김상목;박인석;이상윤;이규화;김동일
    • KSBB Journal
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    • v.13 no.4
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    • pp.438-443
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    • 1998
  • Effects of various environmental factors on cell size index(FCW/DCW) in Thalictrum rugosum. Lithospermum erythrorhizon and Taxus cuspidata plant cell suspension cultures were investigated. Time course change of cell size index were also observed. In batch cultures, FCW/DCW increased according to the decrease of sugar concentration. For short-term experiment within 24 hr, FCW/DCW value could be reduced significantly by increasing sugar concentration. When an osmoticum such as mannitol was added, FCW/DCW converged to a low value. Therefore, it was confirmed that osmolality of the medium was important in determining cell size or water content of the cells. Inorganic salts or treatment with organic solvent also exhibited some effect on the cell size index. However, pH and centrifugal force did not show any influences. On the other hand, it was found that the addition of Pluronic F-68 reduced FCW/DCW. By combining these results effectively, it may be possible to increase the cell concentration in high density culture to a higher extent.

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Risk Factors in Relation to Blood Pressure in Schoolchildren (국민학교 학동의 혈압에 관련된 요인분석)

  • Lee, Dong-Soo;Lee, Kyeong-Soo;Kang, Pock-Soo
    • Journal of Yeungnam Medical Science
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    • v.10 no.2
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    • pp.345-359
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    • 1993
  • This study was conducted to identify the factors related to the blood pressure in school children. The study subjects were 144 boys and 140 girls aged 10 years old, 4th grade student of one elementary school in Taegu City. Blood pressure and 18 variables for 284 school children were measured in May 1992. A weight-for-height index, R$\ddot{o}$hrer index(weight/$height^3$) was calculated for each individual as a measure of obesity. Body fat percent, fat weight, and lean body mass were measured by impedance fat meter(Model SIF-891). Serum total cholesterol, high-density lipoprotein, triglyceride, uric acid, total protein, and electrolyte were measured by automated clinical chemistry analyzer(Hitachi 4020). Low-density lipoprotein and atherogenic index were calculated by the equation. The variables assessed were sex, systolic blood pressure, diastolic blood pressure. R$\ddot{o}$hrer index, body fat percent, body fat weight, lean body mass, total cholesterol, high-density lipoprotein, low-density lipoprotein, uric acid, total protein, serum electrolyte and blood glucose. The mean systolic and diastolic blood pressures for boys were 104.1mmHg and 66.6mmHg and those for girls were 102.9mmHg and 67.5mmHg. Systolic blood pressure of boys was positively correlated with height, weight, R$\ddot{o}$hrer index, fat weight, lean body mass, and triglyceride. Systolic blood pressure of girls was positively correlated with height, weight, lean body mass, and uric acid. Diastolic blood pressure of boys was positively correlated with weight. R$\ddot{o}$hrer index, and lean body mass. Diastolic blood pressure of girls was positively correlated with height, weight, fat weight, and lean body mass and negatively with total serum protein. In multiple regression analysis for the systolic blood pressure, the significant independent variables were R$\ddot{o}$hrer index and serum sodium in boys, and serum uric acid, fat percent, and R$\ddot{o}$hrer index in girls. In multiple regression analysis of the diastolic blood pressure, the significant independent variables were R$\ddot{o}$hrer index in boys and total serum protein in girls. This study indicated that important factors influencing blood pressure in school children were R$\ddot{o}$hrer index, fat percent, serum sodium, uric acid, and total protein. R$\ddot{o}$hrer index was most important among these. It is recommended to enforce the nutritional education for diet control of obesity to prevent hypertention in children and to adopt healthy life-styles that promote good health and prevent development of cardiovascular risk factors.

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Study of Dynamics of Allyl Chloride-2-Butanone Binary System Using Time Domain Reflectometry

  • Sudake, Y.S.;Kamble, S.P.;Patil, S.S.;Khirade, P.W.;Mehrotra, S.C.
    • Journal of the Korean Chemical Society
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    • v.56 no.1
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    • pp.20-27
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    • 2012
  • Complex permittivity spectra of Allyl Chloride (AC), 2-Butanone (2-BU) and their binary mixtures over the entire range of concentration were obtained using the Time Domain Reflectometry (TDR) technique in microwave frequency range at various temperatures. Static dielectric constant and relaxation time are obtained from complex permittivity spectra. Density ($\rho$) and refractive index ($n_D$) are also measured. These parameters are used to determine excess dielectric constant, excess inverse relaxation time, excess molar volume, excess molar refraction, polarity, Bruggeman factor and thermodynamic parameters viz. enthalpy of activation and entropy of activation. The values of static dielectric constant and relaxation time increases while density and refractive index decreases with the percentage of 2-Butanone in Allyl Chloride increases. Excess parameters were fitted to a Redlich-Kister equation.

Studies on AlF3-(Mg+Sr+Ba)F2-P2O5 Glasses II. Effect of MgF2 Contents (AlF3-(Mg+Sr+Ba)F2-P2O5계 유리에 관한 연구 제2보 : MgF2의 영향)

  • 김정은;이종근
    • Journal of the Korean Ceramic Society
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    • v.24 no.3
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    • pp.277-281
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    • 1987
  • The various contents of MgF2 from 0 to 12.5wt% are studied in the AlF3-(Mg+Sr+Ba)F2-P2O5 system for the effects of various properties in glasses and the atmosphere of melting was controlled by N2 and Ar gas respectively. Density, refractive index, infrared transmission, thermal conductivity and thermal expansion coefficient of glasses are determined. Density, refractive index and thermal conductivity are decreased, micro-hardness and thermal expansion coefficient are increased according to the increasing of MgF2 contents. Infrared transmittance decreases with increasing the MgF2 contents and it slightly dropped by air than N2 and Ar atmosphere. Other properties are not influenced by atmosphere control.

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Organic Farming in Korea-I. Study on Microarthropods in Rice Fields of Organic Farming- (유기농업에 관한 연구-I.유기농법 답포장에서의 절지동물상 조사-)

  • 이용환;고현관;황광남;호교순
    • Korean Journal of Organic Agriculture
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    • v.6 no.2
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    • pp.75-80
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    • 1998
  • Organically cultured rice fields were surveyed to compare the population density and the structure of microarthropod communities between chemically controlled and un-controlled fields. In rice fields, microarthropod communities were also compared among four treatments based on different input of fertilzer : 1)No fertilizer, 2)Chemical fertilizer(N-P2O5-K2O = 11 - 7 - 8 kg/10a, 3) Compost (5,000kg/10a), 4) Compost com-plemented with chemical N. Richness index of microarthropod communities in rice fields was greater in the chemically uncontrolled field than controlled field. Within field. the compost plot had greater value of richness index for microarthopod commuities than the non-fertilizer polt. A total of 9 aquatic insects species were identified in the water of organic farming rice field the population density was found to be higher in the compost plot than the other plot. The population of insect pests was found to be high in the late stage of plant whereas the population of insects was high in the early stage of rice plant.

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A Study on the Combustability of Formed Polyethylene (성형 Polyethylene의 연소성에 관한 연구)

  • 정국삼;류영순
    • Journal of the Korean Society of Safety
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    • v.9 no.3
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    • pp.60-66
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    • 1994
  • The purpose of this study is to compare the combustability of the formed high density polyethylene (HDPE) with the low density polyethlyene(LDPE). That is, the easiness of ignition is examined by using the methods with Oxygen Index(OI) Tester and ventilation parameter, and the combustion velocity of these polyethylenes is measured by changing the size and shape of opening area. As the result of it, the oxygen index of HDPE, in a ignition, is required more than LDPE. Then, the concentration distribution of CO by combustion is increased when the opening area is small, but, in the same opening area, LDPE tends to increase more than HDPE. In addition, as the ratio of height to width of opening area is increased, combustion velocity becomes faster relatively. In consequence, when it is generally considered, the combustability of LDPE is better than HDPE.

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Further Results on Performance of LDPC coded IM-OFDM-QOS System

  • Kim, Hyeongseok;Kim, Jeongchang
    • Journal of Broadcast Engineering
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    • v.24 no.7
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    • pp.1221-1227
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    • 2019
  • This paper describes a low-density parity-check (LDPC) coded index modulated orthogonal frequency division multiplexing with quasi-orthogonal sequence (IM-OFDM-QOS) and provides performance evaluations of the proposed system. By using QOS as the spreading code, IM-OFDM-QOS scheme can improve the reception performance than IM-OFDM-SS scheme for a given data rate. On the other hand, LDPC code is widely used to the latest wireless communication systems as forward error correction (FEC) scheme and has Shannon-limit approaching performance. Therefore, by applying LDPC code to IM-OFDM-QOS system as FEC scheme, the reception performance can be further improved. Simulation results show that significant signal-to-noise ratio (SNR) gains can be obtained for LDPC coded IM-OFDM-QOS system compared to the LDPC coded IM-OFDM-SS system and the SNR gain increases with the higher code rate.