• Title/Summary/Keyword: Homogeneity Index

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The Representative Body Type of Lower Body of Chinese Males in Their 20s (중국(中國) 20대(代) 남성(男性)의 하반신(下半身) 대표체형(代表體型) 연구(硏究))

  • Lee, So-Young;Shim, Boo-Ja
    • Journal of Fashion Business
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    • v.11 no.2
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    • pp.58-75
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    • 2007
  • This study held human measurement for 200 male subjects in their twenties in full age living in Ningbo City, Zhejiang Province in China. Their lower body types were classified and grouped according to shapes and sizes. Consequently, representative body type reflecting shapes, sizes, and characteristics were chosen and presented with their measurement values to be used as the basic data for slacks pattern making and fitness evaluation. The following are the results of the analysis: 1. Homogeneity analysis was given to determine the correspondence relationships among index types, indirect types, and size types. Index Type 1 (H-Round), Indirect Type 2 (Adjacent Straight Legs & Slight Slant of Lateral Lower Body), and Size Type 1 (Medium-Thick) were correlated; Index Type 2 (A-Trapezoid), Indirect Type 1 (Bow Legs & Slight Slant of Lateral Lower Body), and Size Type 3 (Small-Slim) were corresponded; Index Type 3 (A-Balance), Indirect Type 3 (Balance Legs & Large Slant of Lateral Lower Body), and Size Type 2 (Tall-Normal) were mutually related. 2. Mahalanobis distance based on each shape factor (index or indirect) and size factor (absolute) was obtained, while an index-absolute representative body type group (47 people, 24.4%) and an indirect-absolute representative body type group (45 people, 23.7%) were chosen, each reflecting shapes, sizes, and characteristics. 3. The representative body type group of lower body shapes of Chinese males in their 20s had average measurement values, such as 169.15cm (stature), 73.32cm (waist circumference), 75.76cm (omphalion waist circumference), 91.08cm (hip circumference), 106.02cm (outside leg length), 53.96cm (thigh circumference), and 74.42cm (crotch length).

A Study on the Quantified Criteria in Determining the Geostructural Domain of Fractured Rock Mass (절리암반내 지구조구 설정을 위한 정량적 기준에 대한 연구)

  • Um Jeong-Gi;Cho Taechin;Kwon Soon Jin
    • Tunnel and Underground Space
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    • v.16 no.1 s.60
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    • pp.26-37
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    • 2006
  • This study addresses the applicability of box fractal dimension, $D_B$, as an index of statistical homogeneity of fractured rock mass. The box-count method's capability in quantifying the combined effect of fracture density and size distribution is examined systematically. Total of 129 two-dimensional fracture configurations were generated based on different combinations of fracture size distribution and fracture density. $D_B$was calculated for the generated fracture network systems using the box-counting method. It was found that was standard deviation of trace length and fracture orientation have no effect on calculated $D_B$. The estimated $D_B$ was found to increase with increasing total density and/or mean trace length. To explore the field applicability of this study, the statistical homogeneity of fractured rock mass was investigated at the rock slope and the underground facility using the box-counting method as well as conventional contingency table analysis. The results obtained in this study clearly show that the methodologies given in this paper have the capability of determining the statistical homogeneity of fractured rock mass.

A Comparative Study on the Local Transmittance Homogeneity of the Ocular Lens (안경 렌즈의 국소적 투과율 균일도 비교 연구)

  • Park, Sang-Kook;Ri, Hyeong-Cheol;Jang, Yun-Seog;Sung, Duk-Yong;Kang, Sung-Soo
    • Journal of Korean Ophthalmic Optics Society
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    • v.20 no.4
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    • pp.471-476
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    • 2015
  • Purpose: We have analyzed the transmittance distribution of various ocular lenses using local transmittance microscope to investigate the optical homogeneity of the lens. Methods: The local transmittance of the laser which is focused on the surface of the spectacle lens was measured by using the photo-detector, lock-in amplifier and motorized-stage. 25 multi-coated lenses with non-tinted of 5 groups and 45 multicoated lenses with tinted of 9 groups were analyzed as a sample respectively. Results: Average and deviation of local transmittance for nontinted lenses were measured almost uniformly with various refractive index and coating. However, deviation of transmittance of for tinted lenses was analyzed as about 3.7 times larger than that of non-tinted lenses. Inhomogeneity of local transmittance of for tinted lenses was also analyzed as about 3.1 times larger than that of non-tinted lenses. Conclusions: We could analyze that standard deviation of transmittance and inhomogeneity of local transmittance of for tinted lenses is larger than that of non-tinted lenses using the local transmittance microscope. These analysis using local transmittance microscope can be utilized as a way to evaluate lens performance and improve optical homogeneity.

A Study on Prospective Plan Comparison using DVH-index in Tomotherapy Planning (토모 테라피 치료 시 선량 체적 히스토그램 표지자를 이용한 치료계획 비교에 관한 연구)

  • Kim, Joo-Ho;Cho, Jeong-Hee;Lee, Sang-Kyoo;Jeon, Byeong-Chul;Yoon, Jong-Won;Kim, Dong-Wook
    • The Journal of Korean Society for Radiation Therapy
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    • v.19 no.2
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    • pp.113-122
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    • 2007
  • Purpose: We proposed the method using dose-volume Histogram index to compare prospective plan trials in tomotherapy planning optimization. Materials and Methods: For 3 patients in cranial region, thorax and abdominal region, we acquired computed tomography images with PQ 5000 in each case. Then we delineated target structure and normal organ contour with pinnacle Ver 7.6c, after transferred each data to tomotherapy planning system (hi-art system Ver 2.0), we optimized 3 plan trials in each case that used differ from beam width, pitch, importance. We analyzed 3 plan trials in each region with isodose distribution, dose-volume histogram and dose statistics. Also we verified 3 plan trials with specialized DVH-indexes that is dose homogeneity index in target organ, conformity index around target structure and dose gradient index in non-target structures. Results: We compared with the similarity of results that the one is decide the best plan trial using isodose distribution, dose volume histogram and dose statistics, and the another is using DVH-indexes. They all decided the same plan trial to better result in each case. Conclusion: In some of case, it was appeared a little difference of results that used to DVH-index for comparison of plan trial in tomotherapy by special goal in it. But because DVH-index represented both dose distribution in target structure and high dose risk about normal tissue, it will be reasonable method for comparison of many plan trials before the tomotherapy treatments.

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Comparison of Doses of Single Scan PBS and Layered Rescanning PBS Using Moving Phantom in Proton Therapy (양성자 치료에서 Moving Phantom을 이용한 Single Scan PBS와 Layered Rescanning PBS의 선량비교)

  • Kim, Kyeong Tae;Kim, Seon Yeong;Kim, Dae Woong;Kim, Jae Won;Park, Ji Yeon;Jeon, Sang Min
    • The Journal of Korean Society for Radiation Therapy
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    • v.31 no.1
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    • pp.43-49
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    • 2019
  • Purpose : We apply the Layered Rescanning PBS designed to complement the Pencil Beam Scanning(PBS), which is vulnerable to moving organs with the Moving Phantom, and compare the homogeneity with the single scan PBS. Methods and materials: Matrix X (IBA, Belgium) and Moving Phantom (standard imaging, USA) were used. A dose of 200 cGy was measured in the AP direction on a hypothetical tumor $10{\times}10{\times}5cm$. The plan type was planned as 4 kinds of sinlge scan PBS, rescan number 4, 8, 12 times. Were measured three times for each types. During the measurement, the respiratory cycle of the Moving Phantom was generally set to 4 seconds per cycle, and the movement radius in the S-I direction was set to 2 cm. In addition, beam on time was measured. Results : The mean values of $D_{max}$ in the PTV were $246.47{\pm}18.8cGy$, $223.43{\pm}8.92cGy$, and $222.47{\pm}7.7cGy$, $213.9{\pm}6.11cGy$ and the mean values of $D_{min}$ were $165.53{\pm}4.32cGy$, $173.13{\pm}11.94cGy$, $184.13{\pm}8.04cGy$, $182.67{\pm}4.38cGy$ and the mean values of $D_{mean}$ $192.77{\pm}6.98cGy$, $196.7{\pm}4.01cGy$, $198.17{\pm}4.96cGy$, $195.77{\pm}3.15cGy$ respectively. As the number of rescanning increased, the Homogeneity Index converged to 1. The beam on time was measured as 2:15, 3:15, 4:30, 5:37 on average. In the measurement process, in the low dose layer of the MU, the problem was found that it was not rescanned as many times as the set number of rescan. Conclusions : In the treatment of tumors with long-term movements, the application of layered rescanning PBS showed a more uniform dose distribution than single scan PBS. And as the number of rescan increase, the distribution of homogeneity is uniform. Compared with single scan plan and 12 rescan plan, HI value was improved by 0.32. Further studies are expected to be applicable to patients who can not be treated with respiratory synchronous radiation therapy.

Robust Planning of Intensity-modulated Proton Therapy for Prostate Cancer (전립선암 치료를 위한 세기조절 양성자 로버스트 치료계획)

  • Park, Su Yeon;Kim, Jong Sik;Park, Ju Young;Park, Won;Ju, Sang Gyu
    • The Journal of Korean Society for Radiation Therapy
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    • v.25 no.1
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    • pp.25-31
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    • 2013
  • Purpose: The aim of this study is to evaluate the dosimetric properties of robust planning strategy for plain intensity-modulated proton therapy (IMPT) taking into account of the uncertainties of effective proton range and set up error as compared to photon intensity-modulated radiation therapy (photon-IMRT) in prostate cancer treatment. Materials and Methods: The photon-IMRT (7 beams, step & shoot), plain-IMPT (2, 4, and 7 portals), and robust- IMPT plans, which was recalculated the plain-IMPT based on the uncertainties of range error (${\pm}5%$) and set up error (0.5 cm), were evaluated for five prostate cancer patients prescribed by 70 Gy/35 fractions. To quantitatively evaluate the dose distributions, several parameters such as maximum dose, minimum dose, mean dose, conformity index (CI), and homogeneity index (HI) for PTV as well as dose-volume index of VxGy for OARs were calculated from dose-volume histograms. Results: Robust-IMPT showed superior dose distributios in the PTV and OARs as compared to plain-IMPT and photon-IMRT. Like plain-IMPT, robust-IMPT were resulted in dose fluctuation around OARs, while better homogeneity and conformity in PTVs and lower mean dose in OARs as compared to photon-IMRT. Conclusion: In consideration with the effective range correction and set up movement using robustness in IMPT plan, the dosimetric uncertainties from plain-IMPT could substantially reduce and suggest more effective solutions than photon-IMRT in prostate cancer treatment.

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Effects of Arc Number or Rotation Range upon Dose Distribution at RapidArc Planning for Liver Cancer (간암환자를 대상으로 한 래피드아크 치료계획에서 아크수 및 회전범위가 선량분포에 미치는 영향)

  • Park, Hae-Jin;Kim, Mi-Hwa;Chun, Mi-Son;Oh, Yeong-Teak;Suh, Tae-Suk
    • Progress in Medical Physics
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    • v.21 no.2
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    • pp.165-173
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    • 2010
  • In this paper, we evaluated the performance of 3D CRT, IMRT and three kind of RA plannings to investigate the clinical effect of RA with liver cancer case. The patient undergoing liver cancer of small volume and somewhat constant motion were selected. We performed 3D CRT, IMRT and RA plannings such as 2RA, limited triple arcs (3RA) and 3MRA with Eclipse version 8.6.15. The same dose volume objectives were defined for only CTV, PTV and body except heart, liver and partial body in IMRT and RA plannings. The steepness of dose gradient around tumor was determined by the Normal Tissue Objective function with the same parameters in place of respective definitions of dose volume objectives for the normal organs. The approach between the defined dose constraints and the practical DVH of CTV, PTV and Body was the best in 3MRA and the worst in IMRT. The DVHs were almost the same among RAs. Plans were evaluated using Conformity Index (CI), Homogeneity Index (HI) and Quality of coverage (QoC) by RTOG after prescription with dose level surrounding 98% of PTV in the respective plans. As a result, 3MRA planning showed the better favorable indices than that of the others and achieved the lowest MUs. In this study, RA planning is a technique that is possible to obtain the faster and better dose distribution than 3D CRT or IMRT techniques. Our result suggest that 3MRA planning is able to reduce the MUs further, keeping a similar or better targer dose homogeneity, conformity and sparing normal tissue than 2RA or 3RA.

The Effects of a Tai Chi Exercise Program for Patients with Arthritis in Rural Areas (농촌지역 관절염대상자를 위한 타이치운동 프로그램 효과)

  • So, Ae-Young;Lee, Kyung-Sook;Choi, Jung-Sook;Lee, Eun-Hee
    • Research in Community and Public Health Nursing
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    • v.21 no.1
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    • pp.118-127
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    • 2010
  • Purpose: The purpose of this study was to evaluate the effects of a Tai-Chi exercise program on subjective health and physiological function index. Methods: This study was designed as non-equivalent control group pretestposttest research. Eighteen women in each group completed the posttest with an attendance rate of 78.3 % after 12 weeks. The Tai Chi exercise program was provided two times a week over three months for the experimental group, but no program for the control group. A questionnaire was used for subjective health index, which consisted of Korean-WOMAC Index for joint stiffness, K-HAQ for physical disability, EQ-5D for quality of life and perceived health status, and CES-D for depression. To measure the effect on the physiological function index, femoral muscle strength, shoulder joint and back flexibility were measured. Results: All variables except left anterior femoral muscle strength had significant homogeneity between the two groups. There were statistically significant differences between the experimental group and the control group in joint stiffness (t=-2.165, p=.03), physical disability (t=-2.231, p=.038), EQ-5D index (t=3.783, p=.001), perceived health status (t=-2.349, p=.025) and femoral posterior muscle strength (t=2.487, p=.038). Conclusion: The Tai-Chi exercise program was beneficial for women with arthritis in rural communities.

Estimates of Regional Flood Frequency in Korea (우리나라의 빈도홍수량의 추정)

  • Kim, Nam-Won;Won, Yoo-Seung
    • Journal of Korea Water Resources Association
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    • v.37 no.12
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    • pp.1019-1032
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    • 2004
  • Flood frequency estimate is an essential index for determining the scale of small and middle hydraulic structure. However, this flood quantity could not be estimated directly for practical design purpose due to the lack of available flood data, and indirect method like design rainfall-runoff method have been used for the estimation of design flood. To give the good explain for design flood estimates, regional flood frequency analysis was performed by flood index method in this study. First, annual maximum series were constructed by using the collected data which covers from Japanese imperialism period to 1999. Wakeby distribution recommended by WMO(1989) was used for regional flood frequency analysis and L-moment method by Hosking (1990) was used for parameter estimation. For the homogeneity of region, the discordance and heterogeneity test by Hosking and Wallis(1993) was carried for 4 major watersheds in Korea. Physical independent variable correlated with index flood was watershed area. The relationship between specific discharge and watershed area showed a type of power function, i.e. the specific discharge decreases as watershed area increases. So flood quantity according to watershed area and return period was presented for each watershed(Han rivet, Nakdong river, Geum river and Youngsan/Seomjin river) by using this relation type. This result was also compared with the result of point frequency analysis and its regionalization. It was shown that the dam construction couldn't largely affect the variation of peak flood. The property of this study was also examined by comparison with previous studies.

Validation of an Instrument to Measure Exercise of Self-Care Agency and its Predictors (자가간호역량의 행사 측정도구의 타당성 및 예측요인 조사)

  • 소향숙;이은숙
    • Journal of Korean Academy of Nursing
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    • v.19 no.3
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    • pp.273-284
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    • 1989
  • The aim of this investigation was to delineate concepts contributing to the Exercise of Self-Care Agency (E.S.C.A.) Scale developed by Kearney & Fleischer (1979) and to test its construct validity and its predictors. The results are summarized as follows ; 1. By means of principal factor analysis and maximal likelihood factor analysis upon data generated from 280 undergraduate students, the factors of Concern about Health Knowledge, self-Concept, Information - Seeking Behavior, Decision -making and Responsibility, Self-esteem, and Passivity emerged. The total percent of variance explained by the 6 factors was 75.1% 2. To assess factor independence and instrument homogeneity, correlations among the 6 factors were computed. The correlations ranged from .24 to .46 indicating that the factors and the items were not too similar or redundant. 3. Test-retest reliability of the total scale is r=.70. Cronbach's $\alpha$ coefficient for internal consistency of the total scale is .86 and that of the factors ranged from .750 to .661 (only factor 6 .497). 4. In additional analysis of the Exercise of Self-Care Agency Scale in relationship to Multiple Health Locus of Control, Family Environmental Scale, and Cornell Medical Index using stepwise multiple regression, the Internal Health Locus of Control Score predicted 21.8%(F=53.34, p=.0001), Family Environmental Score 8.3%(F=22.59, P=.0001), Modified Cornell Medical Index Score 5.4%(F=15.74, P=.0001) of the score of the E.S.C.A.

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