• Title/Summary/Keyword: STRETCHING

Search Result 1,592, Processing Time 0.032 seconds

Analysis of Kidney and Liver from Ultrasonography Images by Using Fuzzy Stretching and Monotone Cubic Spline (Fuzzy Stretching 기법과 Monotone Cubic Spline 보간법을 이용한 초음파 영상에서 간과 신장 영역 분석)

  • Lee, Dae-Woo;Lee, Min-Jung;Hong, Dong-Jin;Kim, Kwang Baek
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2015.05a
    • /
    • pp.148-151
    • /
    • 2015
  • 초음파 검사를 이용한 지방간의 등급을 분류하는 진단 결과는 검사자의 주관적 판단으로 시행하므로 검사자 간의 불일치가 발생하여 초음파 검사의 진단 결과에 영향을 미칠 수 있다. 따라서 본 논문에서는 환자와 검사자에게 지방간 등급을 보다 정확하게 진단하기 위한 전단계로서 초음파 영상에서 간과 신장 영역을 추출하는 방법을 제안한다. 제안된 방법을 다양한 초음파 영상에 적용한 결과, 간과 신장 영역이 비교적 정확히 추출되는 것을 확인할 수 있었다. 따라서 제안된 방법이 초음파 영상에서 지방간을 분석하는데 적용할 수 있다.

  • PDF

Dynamic Modeling Method for Beams Undergoing Overall Rigid Body Motion Considering Two Geometric Non-linear Effects (두 기하학적 비선형 효과들을 고려한 대변위 강체운동을 하는 보의 동적 모델링 방법)

  • Kim, Na-Eun;Yoo, Hong-Hee
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.27 no.6
    • /
    • pp.1014-1019
    • /
    • 2003
  • A dynamic modeling method for beams undergoing overall rigid body motion is presented in this paper. Two special deformation variables are introduced to represent the stretching and the curvature and are approximated by the assumed mode method. Geometric constraint equations that relate the two special deformation variables and the cartesian deformation variables are incorporated into the modeling method. By using the special deformation variables, all natural as well as geometric boundary conditions can be satisfied. It is shown that the geometric nonlinear effects of stretching and curvature play important roles to accurately predict the dynamic response when overall rigid body motion is involved.

High Pressure Effect of Vibration in a Hydrogen Bonding Crystal :$NH_4I$ (수소결합을 가진 결정내의 진동의 고압효과 : $NH_4I$)

  • Jeon Seung-Joon
    • Journal of the Korean Chemical Society
    • /
    • v.36 no.5
    • /
    • pp.627-631
    • /
    • 1992
  • A simple one dimensional model was proposed to describe a hydrogen bonding in crystals, which was based on the Lippincott's empirical potential. The model was used to calculate internal stretching vibrational frequencies of $NH_4I$ crystal at high pressures. The calculated results were in agreement with Raman experimental results qualitatively. At relatively lower high pressures, as pressure increases internal stretching vibrational frequencies shift lower due to increase of the hydrogen bonding effect. At higher pressures, the frequencies shift higher due to the repulsive contribution of interatomic potential induced by the reduction of interatomic distance as pressure increases.

  • PDF

Histogram Stretching of Color Image using Fuzzy Logic (퍼지 논리를 이용한 컬러 영상의 히스토그램 스트레칭)

  • Hwang, Jin-Geun;Woo, Young-Woon;Lee, Won-Joo;Kim, Kwang-Baek
    • Proceedings of the Korean Society of Computer Information Conference
    • /
    • 2011.01a
    • /
    • pp.89-92
    • /
    • 2011
  • 본 논문에서는 컬러 영상에 대해 삼각형 타입의 소속 함수를 적용하여 스트레칭의 상한과 하한을 동적으로 설정하고 영상을 스트레칭 하는 방법을 제안한다. 제안된 퍼지 스트레칭 방법은 평균 밝기 값을 기준으로 가장 어두운 픽셀 값과 가장 밝은 픽셀 값의 거리를 계산하여 밝기의 조정율을 결정한 후, 최소 밝기 값 및 최대 밝기 값을 구하고 삼각형 타입 소속 함수의 구간에 적용한다. 영상의 픽셀 값들을 소속 함수에 적용하여 소속도를 구하고 cut를 적용하여 가장 낮은 픽셀 값을 스트레칭 하한으로 가장 높은 픽셀 값을 스트레칭 상한으로 설정하여 컬러 영상을 스트레칭 한다. 다양한 영상에 적용한 결과, 기존의 스트레칭 방법보다 제안된 퍼지 스트레칭 방법이 효율적인 것을 확인하였다.

  • PDF

Orthopaedic Rehabilitation in Chronic Shoulder Pain (만성 견관절통에 대한 정형외과적 재활치료)

  • Tae, Suk-Kee;Lee, Kee-Hyun
    • Clinics in Shoulder and Elbow
    • /
    • v.6 no.2
    • /
    • pp.99-107
    • /
    • 2003
  • Disorders of the shoulder in which conservative management is indicated as a primary treatment include idiopathic frozen shoulder, atraumatic instability. acute calcific tendinitis , subacromial impingement syndrome, partial thickness or small full thickness tear of the rotator cuff, and chronic rotator cuff tear in elderly population. Aside from medication and various physical modalities used for relief of pain, the mainstay of orthopaedic rehabilitation consists of stretching of the tendons and capsulologamentous complex, and strengtnening of rotator cuff muscles as well as surrounding muscles. However, orthopaedic rehabilitation in chronically painful conditions of the shoulder differs in detail according to the specific diseases or injuries, And it is important to make the rehabilitation program that can be undertaken by the patients rather than adhering to a fixed schedule. Also the program should be changed as the condition of the patient improves or deteriorates. Nevertheless there are basic rules of stretching and strengthening , which should always be observed in applying orthopaedic rehabilitation treatment.

Numerical Analysis of Cyclic Deformation of Polymer Foam Film Using Stretched Truncated Octahedron Model (모서리가 제거된 팔면체 인장모델을 이용한 다공성 폴리머 박막의 반복변형거동 수치해석)

  • Yoo, Ui-Kyung;Lee, Young-Seog
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.27 no.3
    • /
    • pp.104-110
    • /
    • 2010
  • Cyclic deformations of polymer foam film are simulated using the finite element method. Material of polymer foam film is polypropylene (PP). The calculated polymer foam film is micro-scale thin film has cellular structure. The polymer foam film is used in ferro-electret applications. The polymer foam film is idealized to one cell structure as lens shaped stretched truncated octahedron model. Cyclic deformation is performed by uniaxial stretching. Stretching direction is perpendicular to plane of cellular film. Various cyclic strain amplitudes, pore wall thicknesses, pore shape are investigated to find deformation tendency of cellular structure. Consequently, cellular structure has various macroscopic stresses on cyclic deformation with various pore thickness and pore shape.

Charges of TIP4P water model for mixed quantum/classical calculations of OH stretching frequency in liquid water

  • Jeon, Kiyoung;Yang, Mino
    • Rapid Communication in Photoscience
    • /
    • v.5 no.1
    • /
    • pp.8-10
    • /
    • 2016
  • The potential curves of OH bonds of liquid water are inhomogeneous because of a variety of interactions with other molecules and this leads to a wide distribution of vibrational frequency which hampers our understanding of the structure and dynamics of water molecules. Mixed quantum/classical (QM/CM) calculation methods are powerful theoretical techniques to help us analyze experimental data of various vibrational spectroscopies to study such inhomogeneous systems. In a type of those approaches, the interaction energy between OH bonds and other molecules is approximately represented by the interaction between the charges located at the appropriate interaction sites of water molecules. For this purpose, we re-calculated the values of charges by comparing the approximate interaction energies with quantum chemical interaction energies. We determined a set of charges at the TIP4P charge sites which better represents the quantum mechanical potential curve of OH bonds of liquid water.

Springback Control in the Forming Processes for High-Strength Steel Sheets (고강도 강판 성형 공정의 스프링백 제어)

  • 양우열;이승열;금영탁;황진영;윤치상;신철수;조원석
    • Transactions of Materials Processing
    • /
    • v.12 no.8
    • /
    • pp.718-723
    • /
    • 2003
  • Tn order to develop springback control technology for high-strength steel sheets, several studies have been conducted: dome stretching test, stepped s-rail forming and springback measurement, and optimally shaped initial blank design. First, to find out the formability of TRIP60, dome stretching test was performed. Next, the stepped s-rail die, which was designed to form a channel type panel with large twist and wall curl, was manufactured and used to evaluate the effect of controlling forming variables, such as blank holding force and flange amount on the springback. Furthermore, new measurement method of the springback was introduced to define wall curl and twist in geometrically complex panels. Finally, the optimally shaped initial blank was employed to verify one of the best ways to control the springback in channel type. high-strength sheet panels.

Bending analysis of advanced composite plates using a new quasi 3D plate theory

  • Houari, Tarek;Bessaim, Aicha;Houari, Mohammed Sid Ahmed;Benguediab, Mohamed;Tounsi, Abdelouahed
    • Steel and Composite Structures
    • /
    • v.26 no.5
    • /
    • pp.557-572
    • /
    • 2018
  • In this paper, a refined higher-order shear deformation theory including the stretching effect is developed for the analysis of bending analysis of the simply supported functionally graded (FG) sandwich plates resting on elastic foundation. This theory has only five unknowns, which is even less than the other shear and normal deformation theories. The theory presented is variationally consistent, without the shear correction factor. The present one has a new displacement field which introduces undetermined integral variables. Equations of motion are obtained by utilizing the Hamilton's principles and solved via Navier's procedure. The convergence and the validation of the proposed theoretical numerical model are performed to demonstrate the efficacy of the model.