• Title/Summary/Keyword: Wedge Through

Search Result 182, Processing Time 0.03 seconds

Comparison of Enhanced Dynamic Wedge with Physical Metal Wedge based on the Basic Dosimetric Parameters (선량계측인자에 따른 기능강화동적쐐기와 금속쐐기의 비교)

  • Lee Jeong-Woo;Hong Semie;Choi Kyoung-Sik;Chung Jin-Beom;Choe Bo-Young;Jang Hong Seok;Suh Tae-Suk
    • Progress in Medical Physics
    • /
    • v.16 no.2
    • /
    • pp.70-76
    • /
    • 2005
  • For clinical implementation of Enhanced Dynamic Wedge (EDW), it is necessary to adequately analyze and commission its dosimetric properties in comparison to common physical metal wedge (MTW). This study was implemented with the essential measurements of parameters for clinical application, such as percentage depth dose, peripheral dose, surface dose, effective wedge factor, and wedge profile. In addition, through the comparison study of EDW with open and MTW, the analysis was performed to characterize the EDW. We also compared EDW dose profiles of measured values using chamber array 24 (CA24) with calculated values using radiation treatment planning system. PDDs of EDW showed good agreements between $0.2\~0.5\%$ of open beam, but $2\%$ differences with MTW. In the result of the measurements of peripheral dose, it was shown that MTW was about $1\%$ higher than open field and EDW. The surface doses of $60^{\circ}$ MTW showed 10% lower than the others. We found that effective wedge factor of EDW had linear relationships according to Y jaw sizes and was independent of X jaw sizes and was independent of X jaw sizes and asymmetric Y jaw opening. In comparison with measured values and calculate values from Golden-STT based radiation treatment planning system (RTP system), it showed very good agreement within difference of $1\%$. It could be concluded that EDW is a very reliable and useful tool as a beam modification substitute for conventional MTW.

  • PDF

A New Method for Characterization of Composites by Ultrasonics (초음파를 이용한 복합재료 기계적 특성값의 새로운 특정 방법)

  • 장필성;전홍재
    • Composites Research
    • /
    • v.13 no.2
    • /
    • pp.1-7
    • /
    • 2000
  • A new ultrasonic test method is proposed to obtain elastic constants of unidirectional composite materials nondestructively. In the proposed test method, only longitudinal transducers are used to measure wave velocities by through-transmission method. An aluminum wedge and a flat aluminum rectangular block are placed on each side of the test specimen. Oblique incident longitudinal wave is transmitted from a wedge to the specimen and the mode conversions are occurred sequentially at two interfaces between the specimen and aluminium. Measuring wave velocities converted to longitudinal waves in the rectangular block give all information to determine elastic constants of the composites. In order to determine shear stiffness coefficients, transverse wave velocity is measured indirectly from received longitudinal wave. Effects of anisotropy on waves are also considered in this study.

  • PDF

A Study on Shoe Design Affected by Glam Rock (글램 록 스타일 구두 디자인에 관한 연구)

  • Song, Ji-Hyun;Choi, Jeong-Wook
    • The Research Journal of the Costume Culture
    • /
    • v.16 no.6
    • /
    • pp.1156-1168
    • /
    • 2008
  • This study investigated the preceding studies and concept of Glam Rock style, modernistically reinterpreted its aesthetic function and symbolism and connected them to design. It analyzed according to the standards for classification the Glam Rock style appearing mainly in the collections from 2002 S/S to 2007 S/S and presented four pieces of design through the analysis. Its findings are synthesized as follows. First, unstructured design constitutes mule stressing gold cubic overall. It takes an unstable form by the placement of unshapely front ball of foot from transforming Chopin and a relatively poor heel. Second, over trimming constitutes separated pumps in the form of over trimming irregularly a piece of broken glass, metal and thumb tack. Third, Mix & Match combines Boot body of flexible knit material with an acrylic wedge sandal. Fourth, a platform sandal has the structure of color contrast between yellow and bronze in calf fur of tiger-skin pattern. I hope that this study will be developed by reflecting Glam Rock spirit and style as cultural phenomena through analyzing Glam Rock style and presenting design according to selected standards for classification, inferring plastic beauty of fashion shoes from them, investigating the change and feature of age-specific shoe design and making a new attempt possible.

  • PDF

Application of DEW Anchor with Field Test (현장시험을 통한 DEW 지압형 앵커의 적용성평가)

  • Choe, Gyeong-Jip;Park, U-Yeong;Yu, Seong-Jin;Lee, Seong-Rak
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2009.09a
    • /
    • pp.745-751
    • /
    • 2009
  • The anchor is used extensively for a cutting slope, an earth retaining wall, an uplift resistance of sub-structures and so on at civil engineering projects and is classified by aim in use, tendon material, and ground/tension fixing type. It can be distinguished extensively into friction type, bearing type, and complex type by ground fixing type. Generally, bond length of friction type anchor has application to 3~10m depending on the friction-resistance characteristics. In this study, 'DEW(double enlargement wedge) bearing type anchor' of new concept is devised. The bond length is about 0.6~0.8m. It can be used on the ground to have the strength characteristics above it of weathered rock. There are merits which are 'period reduction' and 'cost saving' through the minimum of the boring length. In addition, it is so called environmentally friendly Methods because it can reduce the quantity of carbon dioxide through the reducing drilling machine operation time.

  • PDF

Kinematical Analysis of Pitching wedge swing motion in University Golfer (대학 골프 선수의 Pitching wedge 스윙동작의 운동학적 특성 분석)

  • Back, Jin-Ho;Yoon, Dong-Seob;Kim, Jae-Phil
    • Korean Journal of Applied Biomechanics
    • /
    • v.13 no.3
    • /
    • pp.133-149
    • /
    • 2003
  • The purposes of present study were to determine the major check-points of golf swing from the review of previous studies, and to suggest additional information on the teaching theory of golf. The golf swing motion of 6 male and female elite university golf players were filmed with 16mm Locam II high speed cameras at the speed of 200f/s, and variables such as time, displacement, angle, velocity were calculated and analyzed by 3D Cinematography using DLT method. The results were: 1. Differences were shown in the ratio of weight distribution on the feet, cocking angle, take-back velocity, club-head velocity at impact depending upon the physical characteristics and club used for swing. 2. Time for the down-swing and impact were $0.27{\sim}0.29s$ in men and $0.29{\sim}0.32s$ in women, which was 1/3 of the time for the back-swing. Women showed longer total swing time than men because of longer time in back-swing, follow-through and finish. 3. Men showed larger range of motion in shoulder and knee joints than women, on the other hand women showed larger range of motion in hip joint than men. 4. Cocking motion and right elbow flexion were occurred at the top of back-swing and cocking release was occurred at the moment of impact. Maximum rotations of shoulder and hip joints were found between the top of back-swing and down-swing phase. 5. Women showed lower back-swing velocity than men, and men showed higher club velocity(men: $38.2{\sim}38.6m/s$, women: $35.1{\sim}36.4m/s$) than women.

THE INFLUENCE OF CURING WITH LIGHT TRANSMITTING WEDGE INSERTED INTO THE COMPOSITE RESIN BODY ON THE DEGREE OF MICROLEAKAGE AND MICROHARDNESS (광 전달 쐐기를 이용한 중합 방법이 레진 충전물의 미세 누출과 미세 경도에 미치는 효과)

  • Suh, Yong-Seok;Kim, Yong-Kee;Kim, Jong-Soo
    • Journal of the korean academy of Pediatric Dentistry
    • /
    • v.25 no.4
    • /
    • pp.731-748
    • /
    • 1998
  • The purpose of this study was to test the hypothesis that the more thorough cure of lightactivated composite resin could be obtained if a new way of delivering the light source deep through the resin body is developed when compared to the conventional bulk cure or incremental cure. Using cylindrical resin blocks and natural teeth, various curing conditions were tested for their effects on the degree of microleakage and microhardness. Data were analyzed statistically using One-Way ANOVA and Scheff's Multiple Range test. The results of the present study were as follows: 1. The increment of reduction in microhardness with depth was shown to be higher in group I and II than in group II and V. 2. At the level of lower inner surface and the bottom surface, significantly lower microhardness values were obtained in group I and II when compared to group III, IV and V. Group IV showed the lowest value among three groups(III, IV, V) representing the only statistically significant difference from group V(p<05). 3. Differences between groups in the degree of microleakage detected were shown to be statistically significant (p<05) with the exception of group IV and V at both occlusal and gingival margins. 4. Based upon the above-mentioned results, commonly cited recommendation of incremental curing is strongly supported and the light-transmitting wedge insertion method can be considered as a effective and feasible clinical procedure for the better curing of composite resin. However, more studies under a variety of conditions should be completed before this method is applied actually to the clinical setting.

  • PDF

Modeling on Chloride Diffusivity in Concrete with Isotropic and Anisotropic Crack (등방성 및 이방성 균열을 가진 콘크리트의 염화물 확산계수 모델링)

  • Lee, Hack-Soo;Bae, Sang-Woon;Kwon, Seung-Jun
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.17 no.6
    • /
    • pp.104-111
    • /
    • 2013
  • Deterioration is accelerated due to additional intrusion of chloride ion in crack width in cracked concrete. In this paper, modeling on equivalent diffusion coefficient in cracked concrete is performed for 1-D (Anisotropic) and 2-D (Isotropic) diffusion based on steady state condition. In the previous research, rectangular shape of crack was considered but the shape was modified to wedge shape with torturity. For verification of the proposed model, crack is induced in concrete sample and migration test in steady state is performed for 1-D diffusion. For 2-D diffusion, previous test results are adopted for verification. Through considering wedge shape of crack with torturity, diffusion coefficients in 1-D and 2-D diffusion are reduced, and the more reasonable prediction is obtained. The results from the proposed model with torturity of 0.10~0.15 are shown to be in the best agreement with the test results.

A Study on Slamming Impact Pressure by a Numerical Method based on the Cartesian-grid System (직교격자계 기반의 수치계산법을 이용한 슬래밍 충격압력의 연구)

  • Kim, Ki-Yong;Lee, Young-Gill;Ha, Yoon-Jin;Kang, Ui-Ha;Park, Jeong-Ho;Lee, Sun-Kyu;Lee, Chang-Jin
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.56 no.4
    • /
    • pp.308-315
    • /
    • 2019
  • In this study, numerical simulations of slamming impact pressure acting on the flat plate and wedge type models using the cartesian-grid system and Modified Marker-Density Method (MMD method) were performed and the results were examined. The flat plate and wedge type models were selected as target objects, the turbulence characteristics were considered by applying the Sub-Grid Scale (SGS) turbulence model. Through this study, how the pressure acting on the target objects according to the incident angle influences the slamming impact pressure was examined and the results were compared with the flow characteristics of other experimental results. Also, the degree of slamming impact pressure is evaluated with respect to the cartesian-grid system and MMD method, which is easy to use and has a high degree of calculation for free surface.

Radiographic Comparison of Cranial Tibial Wedge Osteotomy versus Tibial Plateau Leveling Osteotomy: A Cadaveric Study

  • Lee, Jiyoon;Kim, Dongwook;Oh, Hyejong;Lee, Sungin;Choi, Seok Hwa;Kim, Gonhyung
    • Journal of Veterinary Clinics
    • /
    • v.39 no.3
    • /
    • pp.93-99
    • /
    • 2022
  • The present study was performed to compare cranial tibial wedge osteotomy (CTWO) and tibial plateau leveling osteotomy (TPLO) through radiographic evaluation. The experiment was conducted with five cadaver dogs [mean (± SD) weight, 32.9 ± 4.1 kg; mean (± SD) age, 6 ± 2 years; three males and two females] euthanized for reasons unrelated to this study. The cadaver dogs consisted of German Shepherd (n = 3), Belgian Malinois (n = 1), and mixed breed (n = 1). CTWO and TPLO were carried out by the standard surgical method. Radiographic evaluation was performed by comparing several factors, including the flexion and extension angles, the anatomical mechanical axis angle (AMA-angle), tibial length, patellar height measurement using the Labelle-Laurin method, mechanical medial proximal tibial angle (mMPTA), mechanical medial distal tibial angle (mMDTA), and frontal plane alignment (FPA). Both the CTWO and the TPLO groups showed significantly increased flexion angles after surgery. Only the CTWO group had significantly increased extension angle. Although both groups showed significant decreases in the AMA-angle, the mechanical axis moved cranially against the anatomical axis only in the CTWO group. The patellar height was significantly lowered in the CTWO group. No significant differences were found in mMPTA, mMDTA, or FPA. In conclusion, radiographic comparison revealed more changes in CTWO group than in TPLO group.

The Study on Properties and Application of Enhanced Dynamic Wedge Factor (향상된 동적쐐기인자(Enhanced Dynamic Wedge Factor)의 특성 및 적용에 관한 고찰)

  • Kim, Dae-Sup;Ban, Tae-Joon;Yeom, Mi-Suk;Yoo, Soon-Mi;Lee, Woo-Seok;Back, Geum-Mun;Kwon, Kyung-Tae
    • The Journal of Korean Society for Radiation Therapy
    • /
    • v.22 no.1
    • /
    • pp.53-60
    • /
    • 2010
  • Purpose: We try to calculate EDW-factor easily with the formula applies essential data of EDW-factor and evaluate the validity through a measurement. Materials and Methods: We used the given value of GSTT (Golden Segmented Treatment Table) for the calculation of the EDW-factor. As to the experimental device, 0.6 cc farmer-type ion-chamber, an electrometer and water- phantom were used. A measurement was made at the maximum dose depth of the photon beam energy 6 MV and 15 MV under the condition that SSD (Source to Surface Distance) was 100 cm. The angle of the EDW (Enhanced Dynamic Wedge) which we use in an experiment was 60 degree, 30 degree, 20 degree in the Y1-OUT direction. We used Eclipse planning system (Varian, USA) as RTP system and the EDW-factor was calculated about all fields and EDW direction. In order to show the EDW-factor feature, a measurement was made at the selected field that verify the influence of the dependability about X, Y jaw and off-axis field. Results: When we change the Y1 field, it influence on the EDW-Factor and measured value. But the error between measured values and calculated values was less than 1%. The experimental result indicated the tendency that the error of the result of calculation and measured value becomes smaller as the EDW angle become smaller whether the calculation point (measurement point) and iso-center are same or not. The influence of the field size and energy did not show up. We simulated with the same condition using the RTP system. And we found that it makes no difference between the MU which is calculated manually by applying the EDW-Factor obtained from the commercial program and the value which is calculated by using RTP system. Conclusion: We excluded fitting value from well-known EDW-Factor formula and calculated EDW-factor with the formula applies essential data of EDW-factor only. As a result, there are no significant difference between the measured value and calculated value and it showed errors less than 1%. Also, we implemented the commercial program to calculate EDW-Factor conveniently without measure a factor on each field.

  • PDF