• Progress in Medical Physics
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• v.15 no.2
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• pp.100-104
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• 2004

The detector size effect due to the spatial response of detectors is a critical source of inaccuracy in clinical dosimetry that has been the subject of numerous studies. Conventionally, the detector response kernel contains all the information about the influence that the detector size has on the measured beam profile. Various analytical models for this kernel have been proposed and studied in theoretical and experimental works. Herein, a method to simply determine the detector response kernel using the Monte Carlo simulation and convolution theory has been proposed. Based on this numerical method, the detector response kernel for a Farmer type ion chamber embedded in a water phantom has been obtained. The obtained kernel shows characteristics of both the pre-existing parabolic model proposed by Sibata et al. and the Gaussian model used by Garcia-Vicente et al. From this kernel and deconvolution technique, the detector size effect can be removed from measurements for 6MV, 10${\times}$10 $\textrm{cm}^2$ and 0.5${\times}$10 $\textrm{cm}^2$photon beams. The deconvolved beam profiles are in good agreements with the measurements performed by the film and pin-point ion chamber, with the exception of in the tail legion.

• Physical Therapy Rehabilitation Science
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• v.12 no.1
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• pp.48-55
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• 2023

Objective: The purpose of this study is to compare the effects of extracorporeal shock wave therapy (ESWT) and injection therapy through qualitative and quantitative analysis by synthesizing randomized controlled trials (RCTs) conducted on patients with various shoulder diseases. Design: A systematic review and meta-analysis of randomized controlled trials Methods: This review conducted a literature search through international electronic databases in January 2023 to compare the effects of ESWT and injection therapy. Qualitative analysis was performed as a risk of bias tool, and quantitative analysis was synthesized with a random effect model to show the effect size as a standardized mean difference (SMD). Results: Five RCTs involving 298 individuals with shoulder disorders were included in this systematic review and meta-analysis. ESWT showed a moderate effect on pain (SMD=-0.44; 95% CI, -0.95 to 0.06) and a large effect on shoulder function (SMD =-0.81; 95% CI, -1.70 to 0.07) than injection therapy. A significant difference was found in the shoulder range of motion, showing a large effect size (SMD=1.50; 95% CI, 0.58 to 2.43). Conclusions: When considering treatment options for the management of patients complaining of shoulder disorders, it is appropriate to recommend ESWT first rather than injection therapy to increase the range of motion of the joint. In addition, ESWT is safe for pain control and shoulder function improvement, and a positive prognosis could be expected.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.12
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• pp.1669-1674
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• 2005

Maximum likelihood methodology was applied to analyze the efficiency and statistical power of interval mapping by using a threshold model. The factors that affect QTL detection efficiency (e.g. QTL effect, heritability and incidence of categories) were simulated in our study. Daughter design with multiple families was applied, and the size of segregating population is 500. The results showed that the threshold model has a great advantage in parameters estimation and power of QTL mapping, and has nice efficiency and accuracy for discrete traits. In addition, the accuracy and power of QTL mapping depended on the effect of putative quantitative trait loci, the value of heritability and incidence directly. With the increase of QTL effect, heritability and incidence of categories, the accuracy and power of QTL mapping improved correspondingly.

• International Journal of Fluid Machinery and Systems
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• v.4 no.2
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• pp.229-234
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• 2011

For Lift-type Vertical Axis Wind Turbine (VAWT), it is difficult to evaluate the performance through the scale-model wind tunnel tests, because of the scale effect relating to Reynolds number. However, it is beneficial to figure out the critical value of Reynolds number or minimum size of the Lift-type VAWT, when designing this type of micro wind turbine. Therefore, in this study, the performance of several scale-models of Lift-type VAWT (Reynolds number : $1.5{\times}10^4$ to $4.6{\times}10^4$) was investigated. As a result, the Reynolds number effect depends on the blade chord rather than the inlet velocity. In addition, there was a transition point of the Reynolds number to change the dominant driving force from Drag to Lift.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.397-404
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• 2002

The bearing capacity of open-ended piles is affected by the degree of soil plugging, which is quantified by the IFR. There is not at present a design criterion for open-ended piles that explicitly considers the effect of IFR on pile load capacity In order to investigate this effect, model pile load tests using a calibration chamber were conducted on instrumented open-ended piles. The results of these tests show that the IFR increases with increasing relative density and increasing horizontal stress of soils. The unit base and shaft resistances decrease with increasing IFR. Based on the results of the model pile tests, new empirical relations for base load capacity and shaft load capacity of open-ended piles are proposed. In order to check the accuracy of predictions made with the proposed equations, the equations were applied to the full-scale pile load test preformed in this study, Based on the comparisons with the pile load test results, the proposed equations appear to produce satisfactory predictions.

• Steel and Composite Structures
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• v.32 no.6
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• pp.795-806
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• 2019

In this paper, free vibration of sandwich beam with flexible core resting on orthotropic Pasternak is investigated. The top and bottom layers are reinforced by carbon nanotubes (CNTs). This sandwich structural is modeled by Euler and Frostig theories. The effect of agglomeration using Mori-Tanaka model is considered. The Eringen's theory is applied for size effect. The structural damping is investigated by Kelvin-voigt model. The motion equations are calculated by Hamilton's principle and energy method. Using analytical method, the frequency of the structure is obtained. The effect of agglomeration and CNTs volume percent for different parameter such as damping of structure, thickens and spring constant of elastic medium are presented on the frequency of the composite structure. Results show that with increasing CNTs agglomeration, frequency is decreased.

• The Journal of Fisheries Business Administration
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• v.48 no.3
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• pp.47-59
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• 2017

Fish mortality is the most important success factor in aquaculture management. To order fingerlings considering the effect of mortality is a important problem in aquaculture farm. This study is aimed to decision the number and size of fry in aquaculture farm. This study build the mathematical model that finds the value of decision variable to minimize total cost that sums up the fingerling purchasing cost, aquaculture farm operating cost and feeding cost under mortality constraint. The proposed mathematical model involve biological and economical variables: (1) number of fingerlings (2) fish growth rate (3) mortality (4) price of a fry (5) feeding cost, and (6) possible order period. Numerical simulation model presented here in. The objective of numerical simulation is to provide for decision makers to analyse and comprehend the proposed model. When extensive biological and cost data become available, the proposed model can be widely applied to yield more accurate results.

• Communications for Statistical Applications and Methods
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• v.23 no.2
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• pp.179-187
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• 2016

The fixed effects panel probit model faces "incidental parameters problem" because it has a property that the number of parameters to be estimated will increase with sample size. The maximum likelihood estimation fails to give a consistent estimator of slope parameter. Unlike the panel regression model, it is not feasible to find an orthogonal reparameterization of fixed effects to get a consistent estimator. In this note, a hierarchical Bayesian model is proposed. The model is essentially equivalent to the frequentist's random effects model, but the individual specific effects are estimable with the help of Gibbs sampling. The Bayesian estimator is shown to reduce reduced the small sample bias. The maximum likelihood estimator in the random effects model is also efficient, which contradicts Green (2004)'s conclusion.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.231-239
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• 2020

The aim of this paper is to review the role of board size as part of the corporate governance system. This paper discusses one aspect of corporate governance, namely, boards, in the Indonesian context. Using the literature review method, this paper explores factors that need to be considered to determine the optimal number of boards, especially in Indonesia. We explore some determinants of board size, such as complexity and leverage, ownership structure, and financial ratio support. The results reveal that an understanding of the differences found in the two-tier board model helps us understand that the different functions of the board of commissioners and the board of directors require different test treatments from countries that adhere to one-tier systems. A review of the relationship between board size and company performance is expected to provide the corporate governance literature with insights into optimizing the sizes of boards that can improve company performance, both in terms of boards of commissioners and boards of directors. This paper proposes the simultaneous testing of board size's relationship with company performance. The results of this study are expected to make a more real contribution about the effect of board size on company performance.

• Journal of the Korean Society of Clothing and Textiles
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• v.43 no.1
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• pp.51-64
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• 2019

This study provides basic information for the convenient size selection of shirts in the online purchasing environment. The preferred shirt fit was compared according to body size group. The subjects were 111 students majoring in clothing. After setting a virtual model with her own body sizes, subjects chose the best preferred fit among four sizes shirts which included the shirt suitable to her bust circumference, one size smaller shirt, one size larger shirt, and a two size larger shirt. They generally preferred the original size, but the preferred shirt fit was different by the body characteristics such as stature, waist height, or the ratio of Biacromion and drop. Shirt length was affected by stature and sleeve length was affected by waist height. The shoulder ease was mostly affected by the ratio of the shoulder length. Waist fit and hip fit were influenced by waist and hip. Therefore, the body parts affecting the preferred fit of each shirt part were different and the effect of body shape was stronger than body size.