• Title/Summary/Keyword: Gamma Index

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Analysis of Stress Singularities on Interfaces of Friction Welded Dissimilar Materials (마찰용접에 의한 이종재 접합계면에 대한 응력특이성의 해석)

  • Chung, Nam-Yong;Park, Chul-Hee
    • Transactions of the Korean Society of Automotive Engineers
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    • v.13 no.2
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    • pp.142-148
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    • 2005
  • In this paper, the stress singularity on interface of friction welded dissimilar materials was investigated by using 2-dimensional elastic boundary element method. It is required that stress distributions and stress singularities on an interface for friction welded dissimilar materials analize to establish strength evaluation. The stress singularity index ($\lambda$) and stress singularity factor ($\Gamma$) were calculated from the results of stress analysis. The stress singularities on variations for shapes and thickness of friction welded flashes were analized and discussed. This paper suggested that the strength evalution by using the stress singularity factors as fracture parameters, considering the stress singularity on an interface edge of friction welded dissimilar materials were very useful.

Studios on the Battery Activity of Korean $MnO_2$ (국산 이산화망간의 건전지활성도 연구)

  • 김덕묵
    • Journal of the Korean Professional Engineers Association
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    • v.10 no.1
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    • pp.15-18
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    • 1977
  • 국내에서 현재 생산중인 산화방간 4종을 비롯한 기타 여러 지역에 부존된 산화망간 시료와 수입한 산화망간 7종류 중에서 이산화망간의 건전지에 대한 활성도를 각각 실험해 보았다. 실험 방법은 강알카리성에서 Hydrazine Sulfate의 환원력을 이용하여 Activity Index Value를 구하였다. 그 결과 이산화 망간으로 직접 건전지를 만들어 방전시킨 방전곡선과 또한 $\alpha$.$\beta$.${\gamma}$.등의 결정구조가 활성도에 미치는 영향과의 관계가 잘 일치함을 알 수 있고 지금까지는 건전지용 이산화망간의 활성도를 시험하기 위하여 직접 건전지를 제작하여 장시간의 방전시험을 하였던 것을 본 실험에 따르면 Activity Index Value만 측정하여 비교 검토만 하므로서 간단히 그리고 빠른시간 내에 이산화망간의 건전지에 대한 활성도를 확인 결정할 수 있다.

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Erection Penogram with Papaverine and 99m Tc-HSA (파파베린과 테크니시움을 이용한 음경발기촬영술)

  • Choi, Hyung-Ki;Chung, Byung-Ha
    • Clinical and Experimental Reproductive Medicine
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    • v.13 no.2
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    • pp.181-185
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    • 1986
  • To estimate the penile blood flow changes during artificial with erection intracorporeal papaverine injection, we injected 99 m Technitium-Human Serum Albumin via antecubital vein simultaneously and calculate the radioisotope activity of the penis using computerized Gamma Camera. We classified the results into 3 groups according to the transit time, erection persistent time and venous index in 67 impotence patients. We defined the arteriogenic impotence with the delayed transit time (more than 600 seconds) in 13 patients and venogenic with the shortened erection persistant time (less than 200 seconds) and decreased venous index (less than 0.8) in 11 patients. The rest of them (43 patients) were regarded as equivocal impotence, probably nonvasculogenic or psychogenic.

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Analysis of Rheological Properties of Rye Flour (호밀가루의 레올로지 특성분석)

  • Lee, Gwi-Hyun
    • Journal of Biosystems Engineering
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    • v.35 no.6
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    • pp.408-412
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    • 2010
  • Rheological properties of cereals such as rye are great important for the design of die for extrusion and the development of models for extrusion process. Therefore, this study was carried out to analyze the rheological properties according to moisture content of rye flour and extrusion temperature. Rheological properties of rye flour were investigated by using a capillary rheometer for moisture content of three levels (30, 35, 40%) and extrusion temperature of three levels (120, 130, $140^{\circ}C$). Determination coefficients for the relationship between apparent shear stress ($\tau_{ap}$) and apparent shear velocity ($\gamma_{ap}$) were relatively high in the range of 0.973 ~ 0.997 under each extrusion condition. The values of consistency index (K) was decreased with increasing moisture content and extrusion temperature. However, the value of flow behavior index (n) presented the highest value at moisture content of 35%, but it was not affected by extrusion temperature.

Comparison of Stress and Physiological Variables between Diabetic and Nondiabetic Adults

  • Han, Byung-Jo;Choi, Seok-Cheol;Moon, Seong-Min;Kim, Dae-Sik;Hyun, Kyung-Yae
    • Biomedical Science Letters
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    • v.18 no.4
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    • pp.384-390
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    • 2012
  • Diabetes mellitus (DM) is considered to be a serious metabolic disease which may cause systemic complications. The present study was designed to clarify a difference on stress, physiological variables and their correlation between diabetic (DM group) and nondiabetic adults (control group). The levels of body weight, waist circumference, blood pressure, body mass index, body fat mass, total cholesterol (TcH), triglyceride (TG), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase (GGT), total bilirubin (TB), autonomic balance (AB), stress index (SI), fatigue index (FI), and heart rate (HR) were all significantly higher in the DM group than in the control group. However, the levels of autonomic activity (AA), stress resistance (SR), and electrocardiac stability (ES) were significantly lower in the DM group than in the control group. The percentages of persons with abnormal levels in the Tch, high density lipoprotein, low density lipoprotein, TG, AST, ALT and GGT were significantly greater in the DM group than in the control group. In the correlation of glucose and hemoglobin A1c (HBA1c) to stress indices, the DM group had a significant relationship with AB, SR, SI, FI, ES, and HR, whereas the control group had no significant relationship with these, excepting AB. These results suggest that DM was harmfully associated with body, biochemical and stress indices and that blood glucose and HBA1c levels must be exhaustively regulated.

The Effect of Obesity and Nutrient intake on Serum IGF-1 and Serotonin Levels in School Children (초등학생의 비만도와 영양소섭취상태가 혈청 IGF-1과 Serotonin 농도에 미치는 영향)

  • 황권증;이경혜
    • Journal of Nutrition and Health
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    • v.35 no.5
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    • pp.524-530
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    • 2002
  • To evaluate the role of obesity and nutrient intake on serum IGF-1 and serotonin levels in 80 elementary school children (aged 10. 8 yr, 47 boys, 33 girls), we investigated the anthropometric data and the nutrient intake by questionnaries including food daily record, and measured serum IGF-1 and serotonin using RIA and HPLC F-1050 respectively. We obtained the following results by obesity index (underweight-, normal-, obese group). The protein intake of normal group was higher than the others (p < 0.05). The underweight and obese groups had snacks more often than the normal group. The obese group preferred‘cookies’and‘fries’more than the other groups. The serum serotonin levels showed weak correlation with fat (r = 0.315, p < 0.01), fiber (${\gamma}$ = 0.280, p < 0.05) and energy intake (r = 0.242, p < 0.05), but no differences in anthropometric data by obesity index. The serum IGF-1 level was significantly correlated height (r = 0.649, p < 0.001), weight (r = 0.437, p < 0.001) and hip (r = 0.417, p < 0.001), but showed weak correlation with energy intake (r = 0.232, p < 0.05) and carbohydrate intake (r = 0.244, p < 0.05). In this study, we could see only partly correlation among the serum IGF-1 and serotonin and obesity and nutrient intake. Forker research is required into consideration of the essential role of these hormones during a growth period.

Power Investigation of the Entropy-Based Test of Fit for Inverse Gaussian Distribution by the Information Discrimination Index

  • Choi, Byungjin
    • Communications for Statistical Applications and Methods
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    • v.19 no.6
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    • pp.837-847
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    • 2012
  • Inverse Gaussian distribution is widely used in applications to analyze and model right-skewed data. To assess the appropriateness of the distribution prior to data analysis, Mudholkar and Tian (2002) proposed an entropy-based test of fit. The test is based on the entropy power fraction(EPF) index suggested by Gokhale (1983). The simulation results report that the power of the entropy-based test is superior compared to other goodness-of-fit tests; however, this observation is based on the small-scale simulation results on the standard exponential, Weibull W(1; 2) and lognormal LN(0:5; 1) distributions. A large-scale simulation should be performed against various alternative distributions to evaluate the power of the entropy-based test; however, the use of a theoretical method is more effective to investigate the powers. In this paper, utilizing the information discrimination(ID) index defined by Ehsan et al. (1995) as a mathematical tool, we scrutinize the power of the entropy-based test. The selected alternative distributions are the gamma, Weibull and lognormal distributions, which are widely used in data analysis as an alternative to inverse Gaussian distribution. The study results are provided and an illustrative example is analyzed.

Feasibility Study of Mobius3D for Patient-Specific Quality Assurance in the Volumetric Modulated Arc Therapy

  • Lee, Chang Yeol;Kim, Woo Chul;Kim, Hun Jeong;Lee, Jeongshim;Huh, Hyun Do
    • Progress in Medical Physics
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    • v.30 no.4
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    • pp.120-127
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    • 2019
  • Purpose: This study was designed to evaluate the dosimetric performance of Mobius3D by comparison with an aSi-based electronic portal imaging device (EPID) and Octavius 4D, which are conventionally used for patient-specific prescription dose verification. Methods: The study was conducted using nine patients who were treated by volumetric modulated arc therapy. To evaluate the feasibility of Mobius3D for prescription dose verification, we compared the QA results of Mobius3D to an aSi-based EPID and the Octavius 4D dose verification methods. The first was the comparison of the Mobius3D verification phantom dose, and the second was to gamma index analysis. Results: The percentage differences between the calculated point dose and measurements from a PTW31010 ion chamber were 1.6%±1.3%, 2.0%±0.8%, and 1.2%±1.2%, using collapsed cone convolution, an analytical anisotropic algorithm, and the AcurosXB algorithm respectively. The average difference was found to be 1.6%±0.3%. Additionally, in the case of using the PTW31014 ion chamber, the corresponding results were 2.0%±1.4%, 2.4%±2.1%, and 1.6%±2.5%, showing an average agreement within 2.0%±0.3%. Considering all the criteria, the Mobius3D result showed that the percentage dose difference from the EPID was within 0.46%±0.34% on average, and the percentage dose difference from Octavius 4D was within 3.14%±2.85% on average. Conclusions: We conclude that Mobius3D can be used interchangeably with phantom-based dosimetry systems, which are commonly used as patient-specific prescription dose verification tools, especially under the conditions of 3%/3 mm and 95% pass rate.

Feasibility Study of Patient Specific Quality Assurance Using Transit Dosimetry Based on Measurement with an Electronic Portal Imaging Device

  • Baek, Tae Seong;Chung, Eun Ji;Son, Jaeman;Yoon, Myonggeun
    • Progress in Medical Physics
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    • v.28 no.2
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    • pp.54-60
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    • 2017
  • This study was designed to measure transit dose with an electronic portal imaging device (EPID) in eight patients treated with intensity modulated radiotherapy (IMRT), and to verify the accuracy of dose delivery to patients. The calculated dose map of the treatment planning system (TPS) was compared with the EPID based dose measured on the same plane with a gamma index method. The plan for each patient was verified prior to treatment with a diode array (MapCHECK) and portal dose image prediction (PDIP). To simulate possible patient positioning errors during treatment, outcomes were evaluated after an anthropomorphic phantom was displaced 5 and 10 mm in various directions. Based on 3%/3 mm criteria, the $mean{\pm}SD$ passing rates of MapCHECK, PDIP (pre-treatment QA) for 47 IMRT were $99.8{\pm}0.1%$, $99.0{\pm}0.7%$, and, respectively. Besides, passing rates using transit dosimetry was $90.0{\pm}1.5%$ for the same condition. Setup errors of 5 and 10 mm reduced the mean passing rates by 1.3% and 3.0% (inferior to superior), 2.2% and 4.3% (superior to inferior), 5.9% and 10.9% (left to right), and 8.9% and 16.3% (right to left), respectively. These findings suggest that the transit dose-based IMRT verification method using EPID, in which the transit dose from patients is compared with the dose map calculated from the TPS, may be useful in verifying various errors including setup and/or patient positioning error, inhomogeneity and target motions.

Induced Mutant by Gamma Rays and Genetic Analysis for Mutant Characters in Flue-cured Tobacco Variety(Nicotiana tabacum L.) II. Genetic Analysis for Mutant Characters in Flue-cured Tobacco (황색종 연초 품종의 Gamma선에 의한 돌연변이 유기 및 변이형질의 유전분석 II. 변이형질의 유전분석)

  • Jeong, Seok-Hun;Lee, S.C.;Kim, H.B.
    • Journal of the Korean Society of Tobacco Science
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    • v.14 no.2
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    • pp.116-125
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    • 1992
  • This experiment was conducted to examine characteristics of agronomic characters and estimate of gene effect for several mutant characters. The genetic populations were derived from cross between 83H-5 and Hicks. There were significant difference for plant height, stlk height, leaf shape and bacterial wilt disease index except leaf number, leaf length, and what is more, F3 variance is more than Bl and B2 generation from cross 83H-5 X Hicks. Gene actions for stalk height and bacterial wilt disease were estimated by 3-parameter, and by 6- parameter model for all characters except above two characters but stalk height and bacterial wilt disease index are not significant in the additive and dominance effects. Dominant$\times$dominant epitasis for plant height, dominant and dominant$\times$dominant epistasis for leaf length, additive and additive$\times$additive and dominant$\times$dominant epistasis for leaf width, and additive and additive$\times$dominant epistasis for days to flower were appeared significant in gene action.

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