• Title/Summary/Keyword: Effective Width

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The Design of unevenly leaf width distributed Multileaf Collimator (불균일 폭 분포를 갖는 Multileaf Collimator 설계에 관한 연구)

  • 이병용;장혜숙;조병철
    • Progress in Medical Physics
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    • v.5 no.2
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    • pp.45-48
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    • 1994
  • We have studied about leaf-width distribution of Multileaf Collimator(MLC). We have analyzed 1169 treatment fields from 303 patients who have treated by radiation therapy. From this analysis, we can design an unevenly leaf-width distributed MLC, by placing the smaller leaf widths for more frequent blocking region and the larger for less. The average width of total leaves is 0.8 cm, but the effective block width is 0.5-0.6 cm for frequently blocking region(3-6 cm from the field center).

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Genetic Analysis for Agronomic, Chemical , and Leaf Chararters According to Stalk Position in Flue-Cured Tobacco (Nicotiana tabacum L. ) II. Analysis of Gene Action by Diallel Crosses (황색종 연초(Nicotiana tabacum L.)의 주요형질과 엽위별 엽형질에 대한 유전분석 II. 이면교배에 의한 유전자 작용분석)

  • 조수헌
    • Journal of the Korean Society of Tobacco Science
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    • v.9 no.2
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    • pp.37-47
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    • 1987
  • This experiment was conducted to obtain basic information on breeding of flue-cured tabacco varieties . Nine cultivars and partial diallel set of 36 Fl hybrids were grown at Daegu Experiment Station, Korea Ginseng & Tobacco Research Institute in 1983. Partial dominance with high additive gene effect was observed for yield, leaves per plant , days to flower, leaf weight, nicotine and reducing sugar content. partial dominance with additive and dominant gene effect was observed for stalk height , leaf width midrib weight Overdominance with high dominant gene effect was observed for leaf length and midrib width. The directions of dominance were positive for yield, stalk height, leaf weight, leaf length, leaf width, midrib weight, midrib width and reducing sugar content, and the negative was days to flower. The estimates of effective genes were 1 for leaves per plant, 2 for stalk height, days to flower and leaf shape. 3 to 6 for leaf length, leaf width, leaf weight and midrib weight.

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Step-Size Control for Width Adaptation in Radial Basis Function Networks for Nonlinear Channel Equalization

  • Kim, Nam-Yong
    • Journal of Communications and Networks
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    • v.12 no.6
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    • pp.600-604
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    • 2010
  • A method of width adaptation in the radial basis function network (RBFN) using stochastic gradient (SG) algorithm is introduced. Using Taylor's expansion of error signal and differentiating the error with respect to the step-size, the optimal time-varying step-size of the width in RBFN is derived. The proposed approach to adjusting widths in RBFN achieves superior learning speed and the steady-state mean square error (MSE) performance in nonlinear channel environment. The proposed method has shown enhanced steady-state MSE performance by more than 3 dB in both nonlinear channel environments. The results confirm that controlling over step-size of the width in RBFN by the proposed algorithm can be an effective approach to enhancement of convergence speed and the steady-state value of MSE.

Crop Control by Using Neural Network in Edger Mill (신경망을 이용한 Edger압연 크롭저감 연구)

  • 천명식;장대섭;이준정
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1999.08a
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    • pp.438-446
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    • 1999
  • Crop minimization of the top and bottom ends of hot rolled plate, in a plate, in a plate mill, has been investigated. The existing model to determine the edging pattern at the finishing rolling pass was not reasonable to get high width accuracy and rolling yields. New models including width prediction have been formulated by using neural network model of back propagation learning algorithm and statistical analysis based on the actual production rolling data to give the optimal pattern for minimizing trimming loss. Using these models, at a given rolling condition of broadside pass and finishing pass and the permissible condition of width variation, it was possible to minimize crip at the top and bottom ends according to optimum procedure in plate mill. An application to improve the plan view pattern reduced width variation by 23% and crop length by 30% on average with an effective fishtail crop shape.

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Modeling Method of Slabs in RC Flat-Plate Structures Under Lateral loading (횡하중을 받는 RC 무량판 구조의 슬래브 모델링 기법)

  • 최정욱;송진규;이수곤;김진상
    • Journal of the Korea Concrete Institute
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    • v.14 no.4
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    • pp.615-622
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    • 2002
  • To reasonably predict the behaviors for RC flat-plate structures, analysis model considering the flexural stiffness of slabs is required. FEMA 273 and ACI 318-99 refer to theoretical analysis models of two-way slab systems under lateral loading but the actual application method is not suggested. In this study, the modeling and application methods of the flat-plates using effective beam concept are suggested. The results of this study are as follows. 1) The effective beam width model suggested in this study is very useful to model flat-Plate structures subjected to seismic loading for three dimensional analysis 2) The result of analysis for idealized flat-plate example using the effective beam widths considering the effect of the slab crack is shown upper value for displacements. Whereas the model considering effective beam width coefficients only is shown upper value for unbalanced moments

On the direct strength and effective yield strength method design of medium and high strength steel welded square section columns with slender plate elements

  • Shen, Hong-Xia
    • Steel and Composite Structures
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    • v.17 no.4
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    • pp.497-516
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    • 2014
  • The ultimate carrying capacity of axially loaded welded square box section members made of medium and high strength steels (nominal yield stresses varying from 345 MPa to 460 MPa), with large width-to-thickness ratios ranging from 35 to 70, is analyzed by finite element method (FEM). At the same time, the numerical results are compared with the predicted results using Direct Strength Method (DSM), modified DSM and Effective Yield Strength Method (EYSM). It shows that curve a, rather than curve b recommended in Code for design of steel structures GB50017-2003, should be used to check the local-overall interaction buckling strength of welded square section columns fabricated from medium and high strength steels when using DSM, modified DSM and EYSM. Despite all this, EYSM is conservative. Compared to EYSM and modified DSM, DSM provides a better prediction of the ultimate capacities of welded square box compression members with large width-thickness ratios over a wide range of width-thickness ratios, slenderness ratios and steel grades. However, for high strength steels (nominal yield strength greater than 460 MPa), the numerical and existent experimental results indicate that DSM overestimates the load-carrying capacities of the columns with width-thickness ratio smaller than 45 and slenderness ratio less than 80. Further, for the purpose of making it suitable for a wider scope, DSM has been modified (called proposed modified DSM). The proposed modified DSM is in excellent agreement with the numerical and existing experimental results.

Evaluation of shear lag parameters for beam-to-column connections in steel piers

  • Hwang, Won-Sup;Kim, Young-Pil;Park, Yong-Myung
    • Structural Engineering and Mechanics
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    • v.17 no.5
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    • pp.691-706
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    • 2004
  • The paper presents shear lag parameters for beam-to-column connections in steel box piers. Previous researches have analyzed beam-to-column connections in steel piers using a shear lag parameter ${\eta}_o$ obtained from a simple beam model, which is not based on a reasonable design assumption. Instead, the current paper proposes a cantilever beam model and has proved the effectiveness through theoretical and experimental studies. The paper examines the inaccuracy of the previous researches by estimating the effective width, the width-span length ratio L/b, and the sectional area ratio S of a cantilever beam. Two different shear lag parameters are defined using the cantilever model and the results are compared each other. The first type of shear lag parameter ${\eta}_c$ of a cantilever beam is derived using additional moments from various stress distribution functions while the other shear lag parameter ${\eta}_{eff}$ of a cantilever beam is defined based on the concept of the effective width. An evaluation method for shear lag stresses has been investigated by comparing analytical stresses with test results. Through the study, it could be observed that the shear lag parameter ${\eta}_{eff}$ agrees with ${\eta}_c$ obtained from the $2^{nd}$ order stress distribution function. Also, it could be observed that the shear lag parameter ${\eta}_c$ using the $4^{th}$ order stress distribution function almost converges to the upper bound of test results.

The Effect of Wall-squat with Short-Foot Exercise on Pain and Pelvic alignment of Chronic Low Back Pain with Pronated Foot (단축발 운동을 적용한 벽 스쿼트 운동이 엎침발을 동반한 만성 허리통증환자의 통증과 골반 정렬에 미치는 영향)

  • Kim, Nam-Jun;Lee, Han-Suk
    • Journal of the Korean Society of Physical Medicine
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    • v.16 no.4
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    • pp.139-151
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    • 2021
  • PURPOSE: This study examined the effects of wall-squat with short-foot exercise on pain, dysfunction, and pelvic alignment in chronic low back pain patients. METHODS: Thirty outpatients diagnosed with chronic low back pain and pronated foot were enrolled in this study. The patients were divided randomly into a wall-squat with short-foot exercise group (WS; n = 15) and a normal wall-squat exercise group (NW; n = 15). These groups performed their respective exercises 15 times, for three sets, three times a week over six weeks. The visual analogue scale (VAS) was used to measure the subjects' pain, and the Roland-Morris disability questionnaire (RMDQ) was used to measure the subjects' dysfunction. A navicular drop test (NDT) was used to measure the subjects' arch height. To assess the patients' pelvic alignment, their lordosis, sacral tilt, lumbar width, sacral width, ilium length, and ilium width were measured by X-ray imaging. RESULTS: Both the WS and NW groups exhibited significant decreases in their VAS and RMDQ scores after exercise (p < .05). The WS group exhibited significant increases in their arch height (p < .05). Significant differences in the VAS, sacral tilt, sacral width, and ilium length were observed between the WS and NW groups (p < .05). CONCLUSION: These results suggest that wall-squat exercise is effective in decreasing the level of pain and dysfunction in chronic low back pain patients. In addition, the wall-squat with short-foot exercise is considered more effective in improving the pelvic alignment than without short-foot exercise. This can be an effective method for the non-pharmacological and non-surgical treatment of chronic low back pain

Analysis of Biomechanics of Push-up Movement (팔 굽혀 펴기에 대한 생체역학 분석)

  • Rho, Tae-Hwan;Kim, Jeong-Hyo;Park, Si-Baek;Lee, Na-Na
    • Journal of the Korean Society of Physical Medicine
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    • v.4 no.4
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    • pp.269-274
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    • 2009
  • Purpose:The purpose of this study is an interval palmar width according to change of muscle activation under push-up movement. Methods:Three, this study participation normal young adult (male 3, mean age ; 24yaers). The subject performed maximum contraction under push-up movement. EMG activaty patterns is measured with three different width. The EMG activity of pectoralis major and latissimus dorsi were measured using surface electromyography. Results:EMG activation of pectoralis major and latissimus dorsi following of push-up was shown significant difference(p<.05). Also, experiment value was agree with calculation value and width of shoulder position was minimum of pectoralis major and latissimus dorsi muscle activity. Conslusion:RMS values in case of fretum and wide width of the hands on Latissimus Dorsi are shown muscle activity $132{\mu}V$ and $173.5{\mu}V$, respectively. Especialy, RMS value in terms of wide width of the hands on muscles is shown very enhanced muscle activity. It is suggest that interval palmar width of the hands on pectoralis major and latissimus dorsi in push-up movement was effective to intensify of the muscle activity.

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Characteristics Analysis on Teeth Width of Permanent Magnet DC Motor (영구자석 직류전동기의 치폭에 따른 특성해석)

  • Chun, Kyu-Hyuk;Seo, Young-Taek;Bae, Sang-Han;Oh, Chul-Soo
    • Proceedings of the KIEE Conference
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    • 2000.07b
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    • pp.882-884
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    • 2000
  • This paper deals with the effect of teeth width variation in Permanent Magnet DC motor. As teeth width varies, effective flux density is influenced, which is closely related to torque-speed characteristics, output power, and efficiency of the motor. In this study. motor design was carried out using finite element method with various teeth width. Prototype motors under constraints of same armature diameter, material and axial length were made and their performances were tested.

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