• Title/Summary/Keyword: Compression Effect

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Strength Evaluation of a Doubler Plate of a Ship S011c111re subjected to Biaxial In-plane Compression and Shear Load (양축방향 면내압축과 전단하중을 받는 선박 이중판의 강도 평가)

  • 함주혁
    • Journal of Ocean Engineering and Technology
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    • v.15 no.1
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    • pp.85-91
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    • 2001
  • A study for the structural strength analysis on the doubler plate subjected biaxial in-plane compression and shear load has been performed through the systematic evaluation process. In order to estimate the proper static strength of the doubler plate, non-linear elasto-plastic analysis is introduced. Gap element modeling for contact effect between the main plate and the doubler is prepared and nonlinear analysis procedures are illustrated based on MSC/N4W. In addition, some design guides are suggested through the consideration of several important effects such as corrosion of main plate, doubler width, doubler length and doubler thickness. Finally, theses result are compared with a developed design formula based on the buckling strength and general trends. The design guides, according to the variation of design parameters are discussed.

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Basic Examination on 3D Measuring System Using Pulse-Compression

  • Fujimoto Ikumatsu;Ando Shigeru
    • International Journal of Precision Engineering and Manufacturing
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    • v.6 no.4
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    • pp.60-66
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    • 2005
  • In this paper, we propose the basic measurement method of a 3D digitizer using a CCD camera in detail. In the localization measurement with a CCD camera, the effect of the background light and the sensitivity consideration are always problems in realizing a high precision. In this research, a new measurement principle is proposed in which the pulse compression technique known in radar is used to eliminate the effect of background light even under a low intensity light source, and the coordinate values on the CCD camera image plane are determined accurately. From the quantitative evaluation of the S/N ratio improvement and the fundamental experiment, it is verified that a substantial improvement in the S/N ratio is realized for both the background noise and the pixel noise and that a resolution of less than the pixel is sufficiently possible.

A cohesive model for concrete mesostructure considering friction effect between cracks

  • Huang, Yi-qun;Hu, Shao-wei
    • Computers and Concrete
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    • v.24 no.1
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    • pp.51-61
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    • 2019
  • Compressive ability is one of the most important mechanical properties of concrete material. The compressive failure process of concrete is pretty complex with internal tension, shear damage and friction between cracks. To simulate the complex fracture process of concrete at meso level, methodology for meso-structural analysis of concrete specimens is developed; the zero thickness cohesive elements are pre-inserted to simulate the crack initiation and propagation; the constitutive applied in cohesive element is established to describe the mechanism of crack separation, closure and friction behavior between the fracture surfaces. A series of simulations were carried out based on the model proposed in this paper. The results reproduced the main fracture and mechanical feature of concrete under compression condition. The effect of key material parameters, structure size, and aggregate content on the concrete fracture pattern and loading carrying capacities was investigated. It is found that the inner friction coefficient has a significant influence on the compression character of concrete, the compression strength raises linearly with the increase of the inner friction coefficient, and the fracture pattern is sensitive to the mesostructure of concrete.

Development of Compression-Only Bridge Seismic Reinforcement Method (압축전담 교량 내진보강공법 개발 연구)

  • Jang, Yoo-Sik;Yoon, Won-Sub;You, Kwang-Ho
    • Journal of the Korean Society of Industry Convergence
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    • v.25 no.6_3
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    • pp.1221-1230
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    • 2022
  • In this study, a seismic reinforcement method was studied to improve the seismic performance of aged bridges. The construction method developed in this study is a compression-only bridge seismic reinforcement method, and has excellent economic feasibility and workability compared to existing construction methods. In the case of aged bridges, there was an advantage that could compensate for the disadvantages that it was difficult to apply the existing reinforcement method. For the newly developed method, the effect of reinforcement was analyzed through resin analysis. As a result of the analysis, when the reinforcement was applied, the axial reinforcement effect was excellent, and the field applicability was excellent as it showed better results than the existing seismic isolation backing method.

Effect of an Application of Pelvic Compression Belt on the Strength of Hip Flexor in Healthy Young Adult (골반벨트 적용이 건강 성인의 고관절 굴곡근 근력에 미치는 영향)

  • Yoon, Dong-Joon;Kim, Suhn-Yeop;Lee, Eun-Hee;Kim, Se-Lim;Oh, Duck-Won
    • Journal of Korean Physical Therapy Science
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    • v.15 no.4
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    • pp.35-42
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    • 2008
  • Background : To assess the effect of a pelvic compression belt on the strength of hip flexor in healthy young individuals. Study design: Pre- and post-treatment measurement design on one factor was used. Methods : 30 healthy volunteers (male: 15, female: 15) participated in this study. Dynamometer was used to measure the strength of hip flexor, and measurements were performed before and after the application of the pelvic compression belt at neutral position of hip joint and at 30 cm raised position from floor with straight leg in supine. Results : After the application of the pelvic compression belt, the strengths of hip flexor measured at both positions were significantly increased when compared with before the application (p<.05). However, at neutral position of hip joint and at 30cm raised position from floor, there were significantly different in the changing patterns in the strengths of hip flexor between men and women (p>.05). Conclusion : The findings suggest that the pelvic compression belt is helpful in strengthening hip muscles. With easy application, it is sufficiently feasible for clinical use.

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Effect of Musical Rhythm on the CPR education of Adolescent (청소년 대상 심폐소생술 교육에서 음악적 리듬 적용의 교육효과)

  • Tak, Yang Ju
    • Journal of Digital Convergence
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    • v.12 no.2
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    • pp.417-421
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    • 2014
  • We conducted this study to verify effect of applying musical rhythm during the cardiopulmonary resuscitation(CPR) education. From June to October, 2013, we recruited participants of CPR education among mem's high school students. We divided total 57 participants to 2 groups. For experimental group we use musical rhythm during cardiac compression practice to assist adequate cardiac compression rate and for control group do not apply musical rhythm. The group with musical rhythm show more adequate compression rate(16.4sec) than non-rhythmic group(14.4sec). 90% of rhythmic group keep adequate compression rate, but only 44% of non-rhythmic group keep adequate rate. In conclusion, applying musical rhythm to CPR education is more effective to keep correct cardiac compression rate.

Effect of Sequential Intermittent Pneumatic Compression for Lymphedema (임파부종 환자의 간헐적 공기압박 치료의 효과)

  • Kim, Seng-Jung;Rhee, Hyeon-Sook;Kim, Soon-Hee
    • Journal of Korean Physical Therapy Science
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    • v.5 no.2
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    • pp.595-602
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    • 1998
  • The purpose of this study was to investigate the effect of sequential intermittent pneumatic compression in patients with lymphedema who were hospitalized for three days at Samsung Medical Center. Thirty-three subjects with lymphedema was selected by physician referral. A selection of the patients was made according to the following criteria : 1) no known metastases, 2) no infection after the a difference of at least 10% in the volumes of edematous limb. All patients were treated with the Lympha-Press(Model 103-A). Circumferential limb mesurements was done before and after a 3-day treatment period. As a result of sequential intermittent pneumatic compression therapy. All extremity showed a decrease in circumferential measurements with the maximal reduction occurring at the wrist(55.75 %) for the upper extremities and at the lower 1/3 of calf (40.61%) for the lower extremities. Upper extremity arm was reduced by 42.1% and lower extremity leg by 33.61%. In contrast with this, the proximal levels of arm patients and leg showed comparatively poor reduction than distal levels. Almost 44.44% of arm patients and 5.26% of leg patients experienced significant reduction(> 50%) after compression therapy. These data clearly indicates that Sequential Intermittent Pneumatic Compression Therapy was effective treatment for reducing of extremity volume in patients with lymphedema. but this was variable degree and dependent on the amount of pre-existing lymphedema. Other factors such as duration of edema, etiology, previous history of radiology, age did not appear to influence the extend of improvement. Further sutdies will be necessary to determine long term benefit of this therapy.

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The effect of chest compression with voice on cardiopulmonary resuscitation (목소리를 동반한 가슴압박이 심폐소생술에 미치는 영향)

  • Jang, Mun-Sun
    • The Korean Journal of Emergency Medical Services
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    • v.17 no.2
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    • pp.21-28
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    • 2013
  • Purpose : The aim of the study is to compare the effect of cardiopulmonary resuscitation (CPR) with voice and CPR without voice by one rescuer. Methods : Subjects were 26 students in C University who had basic life support certificate for Healthcare Provider. They performed 30:2 CPR for 6 minutes by two groups of CPR with voice and CPR without voice by one rescuer from August 14 to 16, 2012. They performed CPR with Resusci Anne SkillReporter$^{TM}$ and Laerdal PC SkillReporting System Ver. 2.4.1(Laerdal Medical, Norway and recored voice using TES-1350A(TES Electrical Electronic Corp, Taiwan). Between each experiment, 1 day of rest was given, providing enough time to recover from the fatigue of CPR. Results : The depth, rate of chest compression, and ventilation volume were not affected by a voice (p >.05), and the ratio of chest compression to ventilation kept 30:2, when the subject made a sound (p <.05). Conclusion : Making voice during CPR was associated with an accurate ratio of 30:2 and the reduction in hands off time.

Effect of Wearing Compression Clothing on Body Shape (압박의류 착용에 의한 신체변화 연구)

  • Kim, Tae-Gyou;Song, Min-Kyu
    • Fashion & Textile Research Journal
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    • v.12 no.2
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    • pp.233-239
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    • 2010
  • The purpose of this study was to determine the effect of compression clothing on the body shape of the human subjects. Thirty seven healthy females being overweighted with local adiposity on the buttocks and legs between the ages of 20's to 50's were used as the human subjects for the study. The selected subjects wore the compression clothing during 60 days by 8 hours a day. At the start(T0), after 30(T30) and after 60 days of treatment(T60), a cutaneous echography was measured on the right trochanter area of each volunteer in order to assess the thickness of the subcutaneous fatty tissue. At the start(T0), after 30(T30) and after 60 days of treatment(T60), the body weight of each volunteer was taken and the instrumental variations of skinfold measurements of the abdominal fold and inner thigh circumference of the waist, hips and thigh were conducted. The results show that the echography and weight loss of subjects were reduced to 8.34% and 2.08% after 60 days, respectively. Moreover, the skinfold of subjects was also reduced. Finally, skin elastometry of subjects increased.

An Experimental Study on the Stratified Combustion Characteristics in a Direction Injection Gasoline Engine (직접 분사식 가솔린 엔진을 이용한 성층 연소 특성에 관한 실험적 연구)

  • Lee, Chang-Hee;Lee, Ki-Hyung;Lim, Kyoung-Bin;Kim, Bong-Gyu
    • Transactions of the Korean Society of Automotive Engineers
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    • v.14 no.2
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    • pp.121-126
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    • 2006
  • A gasoline-fueled stratified charge compression ignition (SCCI) engine with both direct fuel injection and intake temperature and compression ratio was examined. The fuel was injected directly by using the high temperature resulting from heating intake port. With this injection strategy, the SCCI combustion region was expanded dramatically without any increase in NOx emissions which were seen in the case of compression stroke injection. Injection timing during the intake temperature was found to be an important parameter that affects the SCCI region width. The effect of mixture stratification and the effect of fuel reformation can be utilized to reduce the required intake temperature for suitable SCCI combustion under each set of engine speed and compression ratio conditions.