• Title/Summary/Keyword: Distribution volume

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Analysis of buckling response of functionally graded sandwich plates using a refined shear deformation theory

  • Abdelhak, Z.;Hadji, L.;Khelifa, Z.;Hassaine Daouadji, T.;Adda Bedia, E.A.
    • Wind and Structures
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    • v.22 no.3
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    • pp.291-305
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    • 2016
  • In this paper, a refined shear deformation plate theory which eliminates the use of a shear correction factor was presented for FG sandwich plates composed of FG face sheets and an isotropic homogeneous core. The theory accounts for parabolic distribution of the transverse shear strains and satisfies the zero traction boundary conditions on the surfaces of the plate. The mechanical properties of the plate are assumed to vary continuously in the thickness direction by a simple power-law distribution in terms of the volume fractions of the constituents. Based on the present refined shear deformation plate theory, the governing equations of equilibrium are derived from the principle of virtual displacements. Numerical illustrations concern buckling behavior of FG sandwiches plates with Metal-Ceramic composition. Parametric studies are performed for varying ceramic volume fraction, volume fraction profiles, Boundary condition, and length to thickness ratios. The accuracy of the present solutions is verified by comparing the obtained results with the existing solutions.

Droplet Sizes and Velocities from Single-Hole Nozzle in Transversing Subsonic Air-stream (아음속 횡단류에 수직 분사되는 분무의 액적크기 및 속도 분포 특성)

  • Lee, In-Chul;Cho, Woo-Jin;Lee, Bong-Su;Kim, Jong-Hyun;Koo, Ja-Ye
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2007.04a
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    • pp.106-109
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    • 2007
  • The spray plume characteristics of liquid water jet injected into subsonic cross-flow at 42 m/s were experimentally investigated. Nozzle has a 1.0 m diameter and L/D=5. Droplet sizes, velocities, volume flux were measured at each downstream area of the injector exit using phase Doppler particle anemometry. Measuring probe position is moved with 3-way transversing machine. Experimental results indicate that SMD is varied from 75 to $120{\mu}m$ distribution and it is uncertain layer structure. SMD peaks at the top of the spray plume. This phenomenon is related to the momentum exchange between column waves and cross-flow stream. Droplet vector velocities were varied from 11.5 to 33 m/s. A higher-velocity region can be identified in down edge region at Z/D : 40, 70 and 100. Lower-velocity region were observed on bottom position of the spray plume. Volume flux is a criterion to the droplet concentration. All volume flux distribution has a same structure that continuously decreases from the center region to the edge of the plume. Z/D : 20 is spatially less concentrated than in Z/D : 100.

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The Visual Illusion Using the Adequate Ease Distribution of Jacket Pattern for the Middle Aged Women of Obese Figure (중년비만 여성용 재킷패턴의 여유량 분포에 따른 착시효과)

  • Sohn, Boo-Hyun
    • Korean Journal of Human Ecology
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    • v.17 no.3
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    • pp.469-483
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    • 2008
  • Body image is important as it is related to self-esteem and can be enhanced by clothing and the degree of enhancement is related to clothing fit. The purpose of the paper is to find the adequate ease distribution of jacket pattern for the obese women who want to slenderize their shape by optical illusion. Subjective evaluation of the visual appearance we collected and, at the same time, 3D clothing air volume was observed for the nine types of experimental jackets with different ease distribution. As results it was found that jacket pattern for the obese women is that the front width of pattern is wider than what of back width in waist and abdomen. It was also noted that there was distance between clothing and skin in the girth around hip of jacket. 3D scanner clearly demonstrated the distribution of ease is useful to find the pattern variables responsible for the slender appearance of the obese women. The ready-to-made clothes for the obese women's clothing should be manufactured systematically in due consideration of the diversity and scarcity of the obese women's body shape.

Bioavailability and Comparative Pharmacokinetics of Two Enrofloxacin Formulations in Broiler Chickens (육계에서 경구투여시 enrofloxacin 제제에 따른 생체이용율 및 약물동태)

  • 윤효인;박승춘
    • Journal of Veterinary Clinics
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    • v.14 no.2
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    • pp.195-200
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    • 1997
  • In order to compare the pharmacokinetic profiles of enrofloxacin-HCL)ENFLX-HCL) and enrofloxacin-KOH (ENFLX-KOH) after oral administration in broiler chickens, the study was performed. The chickens used in this study weighed $1.82 {\pm}0.2 kg$ and clinically healthy. The dose of intravenous and lral administration was 5 mg per kg of body weight as enrofloxacin. After intravenous injection of enrofloxacin, it showed two-compartment model with the rapid distribution phase and the slow elimination phase. The mean apparent volume of distribution (Vd) was 2.70 l/kg. The mean half-life of elimination and distribution showed 8.26 h and 0.44 h, respectively. The mean area under curve (AUC) was calculated as $19.7 {\mu} g{\cdot} h/ml$. After oral administration of ENFLX-HCL and ENFLX-KOH with a rate of dose 5 mg of enrofloxacin/kg of body weight, Both of the products were showed one-compartment model unlike that of i.v. enrofloxacin standard solution showed the mean bioavailability of 79.64% for the ENFLX-KOG and 86.24% for the ENFLX-HCL. The mean total body clearance of the former was 0.24 l/kg/h and the latter 0.42 l/kg/h. Both enorfloxacin formulations seemed to have good tissue distribution and penetration as indicated by large volume of distribution : 2.72 l/kg for the -KOH and 4.44 l/kg for the -HCL. With the results obtained in this study, ENFLX-HCL could be used in place of its salt form in chickens.

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The Influence of Volume Effect in 2D-array Ion Chamber on the Measurement of IMRT Dose Distribution (2차원 배열형 이온함의 부피효과가 세기조절방사선치료의 선량분포 측정에 미치는 영향)

  • Kim, Sung Joon;Lee, Seoung Jun;Park, In Kyu;Lee, Jeong Eun;Park, Shin Hyung;Seol, Ki Ho;Kim, Jae Chul
    • Progress in Medical Physics
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    • v.24 no.1
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    • pp.41-47
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    • 2013
  • We evaluated the influence of volume effect on the measurement of IMRT dose distribution by comparing a 2D-array ion chamber and other dosimeters. Matrix phantom which is a 2D-array ion chamber having volume effect was compared with beam image system and film for the measurement of dose distribution. Five intensity-modulated radiation therapy plans were created using five fields in thevirtual phantom. The measured dose distribution was compared with the calculated one by radiation treatment planning system and analysis program. We evaluated the conformity of dose distribution by calculating correlation coefficients and gamma values. The highest error rate of 1.3% was associated with matrix phantom in which volume effect in small field sizes was substantial.

Body Fluid Volumes of Korean Native Goats (한국재래(韓國在來) 염소의 체액량(體液量))

  • Yang, Il Suk;Rhee, Young So;Chung, Soon Tong
    • Korean Journal of Veterinary Research
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    • v.16 no.2
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    • pp.187-190
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    • 1976
  • In order to approximate plasma volume, extracellular fluid volume and total body water volume of Korean native goats, measurements were made of the volumes of distribution of Evans blue, potasium thiocyanate and antipyrine. The results obtained in this work were summarized as follows: 1. Plasma volume showed a range of 50 to 72ml/kg with a mean of $62{\pm}6.2ml/kg$ (SD). 2. Blood volume showed a range of 69 to 98ml/kg with a mean of $85{\pm}7.9ml/kg$. 3. Extracellular fluid volume showed a range of 265 to 310ml/kg with a mean of $297{\pm}18.3ml/kg$. 4. Interstitial fluid volume showed a range of 204 to 261ml/kg with a mean of $236{\pm}16.8ml/kg$. 5. Intracellular fluid volume showed a range of 380 to 436ml/kg with a mean of $420{\pm}12.6ml/kg$. 6. The volume of total body water showed a range of 680 to 735ml/kg with a mean of $714{\pm}17.7ml/kg$.

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Assessment of The Accuracy of The MR Abdominal Adipose Tissue Volumetry using 3D Gradient Dual Echo 2-Point DIXON Technique using CT as Reference

  • Kang, Sung-Jin
    • Journal of Magnetics
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    • v.21 no.4
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    • pp.603-615
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    • 2016
  • In this study, in order to determine the validity and accuracy of MR imaging of 3D gradient dual echo 2-point DIXON technique for measuring abdominal adipose tissue volume and distribution, the measurements obtained by CT were set as a reference for comparison and their correlations were evaluated. CT and MRI scans were performed on each subject (17 healthy male volunteers who were fully informed about this study) to measure abdominal adipose tissue volume. Two skilled investigators individually observed the images acquired by CT and MRI in an independent environment, and directly separated the total volume using region-based thresholding segmentation method, and based on this, the total adipose tissue volume, subcutaneous adipose tissue volume and visceral adipose tissue volume were respectively measured. The correlation of the adipose tissue volume measurements with respect to the observer was examined using the Spearman test and the inter-observer agreement was evaluated using the intra-class correlation test. The correlation of the adipose tissue volume measurements by CT and MRI imaging methods was examined by simple regression analysis. In addition, using the Bland-Altman plot, the degree of agreement between the two imaging methods was evaluated. All of the statistical analysis results showed highly statistically significant correlation (p<0.05) respectively from the results of each adipose tissue volume measurements. In conclusion, MR abdominal adipose volumetry using the technique of 3D gradient dual echo 2-point DIXON showed a very high level of concordance even when compared with the adipose tissue measuring method using CT as reference.

Optimization and Mathematical Modeling of the Transtubular Bioreactor for the Production of Monoclonal Antibodies from a Hybridoma Cell Line

  • Halberstadt, Craig R.;Palsson, Bernhanrd O.;Midgley, A.Rees;Curl, Rane L.
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.7 no.3
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    • pp.163-170
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    • 2002
  • This report describes the use of a transtubular bioreactor to study the relative effects of diffusion versus perfusion of medium on antibody production by a hybridoma cell line. The study was performed with a high-density cell culture maintained in a serum-free, low-protein medium for 77 days. It was determined that the reactor possessed a macro-mixing pattern residence time distribution similar to a continuous stirred tank reactor (CSTR), However, due to the arrangement of the medium lines in the reactor, the flow patterns for nutrient distribution consist of largely independent medium path lengths ranging from short to long. When operated with cyclic, reversing, transtubular medium flow, some regions of the reactor (with short residence times) are more accessible to medium than others (with long residence times). From this standpoint, the reactor can be divided into three regions: a captive volume, which consists of medium primarily delivered via diffusion; a lapped volume, which provides nutrients through unilateral convection; and a swept volume, which operates through bilateral convection. The relative sizes of these three volumes were modified experimentally by changing the period over which the direction of medium flow was reversed from 15 min (larger captive volume) to 9 h (larger swept volume). The results suggest that antibody concentration increases as the size of the diffusion-limited (captive) volume is increased to a maximum at around 30 min with a sharp decrease thereafter. As reflected by changes in measured consumption of glucose and production of lactate, no significant difference in cellular metabolism occurred as the reactor was moved between these different states. These results indicate that the mode of operation of the transtubular bioreactor may influence antibody productivity under serum-free, low-protein conditions with minimal effects on cellular metabolism.

The Proper Volume and Distribution of Cement Augmentation on Percutaneous Vertebroplasty

  • Kim, Dong-Joon;Kim, Tae-Wan;Park, Kwan-Ho;Chi, Moon-Pyo;Kim, Jae-O
    • Journal of Korean Neurosurgical Society
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    • v.48 no.2
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    • pp.125-128
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    • 2010
  • Objective : The purpose of this study was to determine the optimal volume of injected cement and its distribution when used to treat vertebral compression fractures, and to identify factors related to subsequent vertebral fractures. Methods : A retrospective analysis of newly developing vertebral fractures after percutaneous vertebroplasty was done. The inclusion criteria were that the fracture was a single first onset fracture with exclusion of pathologic fractures. Forty-three patients were included in the study with a minimum follow up period of six months. Patients were dichotomized for the analysis by volume of cement, initial vertebral height loss, bone marrow density, and endplate-to-endplate cement augmentation. Results : None of the four study variables was found to be significantly associated with the occurrence of a subsequent vertebral compression fracture. In particular, and injected cement volume of more or less that 3.5 cc was not associated with occurrence (p = 0.2523). No relation was observed between initial vertebral height loss and bone marrow density (p = 0.1652, 0.2064). Furthermore, endplate-to-endplate cement augmentation was also not found to be significantly associated with a subsequent fracture (p = 0.2860) by Fisher's exact test. Conclusion : Neither volume of cement, initial vertebral height loss, bone marrow density, or endplate-to-endplate cement augmentation was found to be significantly related to the occurrence of a subsequent vertebral compression fracture. Our findings suggest that as much cement as possible without causing leakage should be used.

Evaluation of Sampling Methodology for the Measurement of Polycyclic Aromatic Hydrocarbons in the Atmosphere (대기 중 다환방향족 탄화수소의 측정을 위한 시료포집방법의 비교평가)

  • 백성옥;최진수
    • Journal of Korean Society for Atmospheric Environment
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    • v.14 no.1
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    • pp.43-62
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    • 1998
  • This study was carried out to investigate the influence of different sampling methods on the measured concentrations of polycyclic aromatic hydrocarbons (PAH) both in the vapor and particulate phases, and to evaluate the effects of ambient temperature and sampling duration on the losses of PAH associated with particle samples due to volatilization. The experimental protocol of this study is consisted of two parts. The first part is related to the comparison of PAH concentrations measured by 4 different sampling systems, each of which involves different sampling principles for comparison purposes, including a medium-volume sampler with XAD-2 adsorbent, a high-volume sampler with polyurethane foam (PUF), two identical low-volume samplers: one with XAD-2 and the other with PUF, respectively. The second part of this study is to quantitatively estimate the losses of particulate PAH samples by volatilization during sampling, using two identical low-volume samplers: one was used for changing the filters every 3 hrs, 6 hrs, 12 hrs, and 24 hrs sampling, while the other was maintained for continuous 48 hours sampling without changing the filter. The concentrations of volatile PAH including 2-3 rings appeared to be significantly affected by the type of adsorbent. Measured levels of these lower-molecular weight PAH by XAD-2 adsorbent were much higher than those by PUF for both high-volume and low-volume sampling. PUF was found to give rise to unknown components that interfered with the PAH analysis, even after extensive clean-up. In addition, the retention efficiency of PUF for lower molecular weight PAH was subject to a large variation, being significantly influenced by sampling conditions such as ambient temperature. However, the effect of sampling methods with different adsorbents on the measured levels of semi-volatile compounds including 4 rings PAH such as fluoranthene, pyrene, BaA and chrysene, was not so much significant as more volatile PAH compounds. It was also clear from this study that volatilization losses of the semi-volatile PAH collected on the filters were inevitably occurred during prolonged sampling, and hence the results obtained from conventional sampling methods may not be expected to yield an accurate distribution of PAH between the vapor and particulate phases.

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