• Title/Summary/Keyword: Contraction stress

Search Result 200, Processing Time 0.03 seconds

A Comparative Study on the Effects on Urinary Incontinence between Pelvic Floor Muscle Exercise and Magnetic Stimulation Therapy (지역사회 요실금 여성의 골반저근운동과 자기장자극 효과비교)

  • Cho, Myung-Sook;Kang, Hae-Young
    • Research in Community and Public Health Nursing
    • /
    • v.19 no.4
    • /
    • pp.696-703
    • /
    • 2008
  • Purpose: To Perform a randomized comparative study investigating the effects of Pelvic Floor Muscle Exercise(PME) and Magnetic Stimulation Therapy(MST) and to identified the problems in each of PME & MST Method: Forty-nine patients with mild stress incontinence were randomly assigned to either of two treatment groups (24 patients in the PME group and 25 in the MST group). The PME group had a video exercising program for 40 times every day during 6 weeks. The MST group was treated with BioCon-2000TM, 2times/ week for six weeks. Pre-test and post-test were performed by Prineometer, 1-hour pad test. and Jackson's BFLUTS questionnaire of Jackson. Collected data were analysed using SAS 9.1 by frequency, Kolmogorov-Smirnov Z. Chi Square-test, t-test, Fisher Exact probability test, Paired t-test, and Wilcoxon's rank sum test. Results: In comparison between before and after PME and MST, statistically significant difference was observed in maximal vaginal pressure, duration of vaginal contraction, amount of urine, and symptom of urination. In the comparison of the effectiveness between PME & MST, only the maximal of vaginal pressure (Z=2.58, p= .010) was significantly different. Conclusion: The factor more effective in the MST group than in the PME group was high compliance.

  • PDF

Association between Health-related Characteristics of the Middle-aged between Men and Women, and Oral Health-related Characteristics on Depressive Symptoms (PHQ-9) (중장년층의 성별에 따른 건강관련 특성 및 구강건강관련 특성과 우울증상(PHQ-9)의 관련성)

  • Lee, Eun-Ju
    • The Korean Journal of Health Service Management
    • /
    • v.11 no.4
    • /
    • pp.179-188
    • /
    • 2017
  • Objectives : This study tried to examine whether there is any difference between the middle-aged men and women in terms of the effect of health-related and oral health-related characteristics on their depressive symptoms (PHQ-9). Methods : We used the 2nd year data of the 6th session of the National Health and Nutrition Survey of 2,008 adults(aged40~64 years) for fulfilling the research objectives. Results : The analysis showed that among middle-aged male and female respondents, household income, subjective health conditions, and stress perception among health-related characteristics had common elements affecting their depressive symptoms. The self-reported oral health conditions affected depressive symptoms for male respondents. On the other hand, chewing problems and contraction of periodontal disease affected depressive symptoms of female respondents. Conclusions : Thus, it is necessary to consider the effect of sex in the relationship between health-related and oral health-related characteristics, and to make efforts to develop differential programs to manage and prevent depressive symptoms among men and women.

A Study on Dynamic Strength Analysis of Submarine Considering Underwater Explosion (내충격 성능을 고려한 수중함 동적 강도 설계에 관한 연구)

  • Son, Sung-Wan;Choi, Su-Hyun;Kim, Kuk-Su
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2000.06a
    • /
    • pp.1185-1191
    • /
    • 2000
  • In general, the strength of hull structures can be estimated from stress evaluation considering static and hydro-dynamic load due to sea-wave. However, war ships such as submarine, have frequently experienced the underwater explosion and local structures of ship as well as hull girder can be damaged by the dynamic response excited from underwater non-contact explosion. When explosion happens at underwater, shock wave is radiated In early short time, then gas bubbles are generated, and expansion and contraction are repeated as they float to the surface. The shock wave causes the damage of equipment and its supporting structures, on the other hand, the hull girder strength can be lost by resonance between bubble pulsation and lowest ship natural vibration period. In this paper, the hydro-Impulse force due to bubble was calculated. Based on these results the hull girder strength of submarine was estimated from transient response analysis by using NASTRAN. Also, shock analysis for some equipment supporting structures was carried out by using DDAM. In order to evaluate the strength of these local structures due to shock wave.

  • PDF

Dynamic Characteristics of Magneto-rheological Fluid Actuator for Micro-motion Control (미세동작제어를 위한 자기유변유체 구동기의 동적 특성)

  • Kim, Pyunghwa;Han, Chulhee;Suresh, Kaluvan;Park, Choon-Yong;Shin, Cheol-Soo;Choi, Seung-Bok
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.26 no.5
    • /
    • pp.511-517
    • /
    • 2016
  • This paper presents dynamic characteristics of a new actuator using magneto-rheological(MR) fluid between two electrode type coils. The concept of the actuator is to strengthen the force due to the magnetic field produced by the electrode-coil for MR fluid. The amount and direction of current input to the electrode-coils decide the characteristics of contraction-mode and extension-mode. For achieving the required actuating displacement and actuating force, the yield stress of the MR fluid between two electrode-coils is precisely changed by the input current. In this work, the MR fluid is operated in squeeze mode. The experimental results shown in this paper depict that it can be applied in the micro-level displacement and vibration control system.

Cementing failure of the casing-cement-rock interfaces during hydraulic fracturing

  • Zhu, Hai Y.;Deng, Jin G.;Zhao, Jun;Zhao, Hu;Liu, Hai L.;Wang, Teng
    • Computers and Concrete
    • /
    • v.14 no.1
    • /
    • pp.91-107
    • /
    • 2014
  • Using the principle of damage mechanics, zero-thickness pore pressure cohesive elements (PPCE) are used to simulate the casing-cement interface (CCI) and cement-rock interface (CRI). The traction-separation law describes the emergence and propagation of the PPCE. Mohr-coulomb criteria determines the elastic and plastic condition of cement sheath and rock. The finite element model (FEM) of delamination fractures emergence and propagation along the casing-cement-rock (CCR) interfaces during hydraulic fracturing is established, and the emergence and propagation of fractures along the wellbore axial and circumferential direction are simulated. Regadless of the perforation angle (the angle between the perforation and the max. horizontal principle stress), mirco-annulus will be produced alonge the wellbore circumferential direction when the cementation strength of the CCI and the CRI is less than the rock tensile strength; the delamination fractures are hard to propagate along the horizontal wellbore axial direction; emergence and propagation of delamination fractures are most likely produced on the shallow formation when the in-situ stresses are lower; the failure mode of cement sheath in the deep well is mainly interfaces seperation and body damange caused by cement expansion and contraction, or pressure testing and well shut-in operations.

Tests of the interface between structures and filling soil of mountain area airport

  • Wu, Xueyun;Yang, Jun
    • Geomechanics and Engineering
    • /
    • v.12 no.3
    • /
    • pp.399-415
    • /
    • 2017
  • A series of direct shear tests were conducted to investigate the frictional properties of the interface between structures and the filling soil of Chongqing airport fourth stage expansion project. Two types of structures are investigated, one is low carbon steel and the other is the bedrock sampled from the site. The influence of soil water content, surface roughness and material types of structure were analyzed. The tests show that the interface friction and shear displacement curve has no softening stage and the curve shape is close to the Clough-Duncan hyperbola, while the soil is mainly shear contraction during testing. The interface frictional resistance and normal stress curve meets the Mohr-Coulomb criterion and the derived friction angle and frictional resistance of interface increase as surface roughness increases but is always lower than the internal friction angle and shear strength of soil respectively. When surface roughness is much larger than soil grain size, soil-structure interface is nearly shear surface in soil. In addition to the geometry of structural surface, the material types of structure also affects the performance of soil-structure interface. The wet interface frictional resistance will become lower than the natural one under specific conditions.

An Experimental Study on the Mechanical Properties of High Strength of High Strength Concrete Subject to High Temperature Heating (고온가열을 받은 고강도 콘크리트의 역학적 특성에 관한 실험적 연구)

  • Lee, Tae-Gyu;Sin, Seung-Bong;Kim, Young-Sun;Lee, Seung-Hoon;Kim, Gyu-Yong;Kim, Moo-Han
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2007.04a
    • /
    • pp.9-12
    • /
    • 2007
  • Recently, research and development related to high strength concrete for the high rise and large scale reinforced concrete building has been actively promoted in worldwide by national and private research project. But, it is reported that violent explosive explosion would be happened when it was exposed in fire. In the existed study, a explosion in a reinforced concrete structure looses the organism by the different contraction and expansion of hardened cement paste and aggregate, and causes crack by thermal stress. In case of the Europe, Japan and America, they have studied the explosion for a long time. However it would hardly study the explosion in domestic, So it is needed base on mechanical properties of fire deterioration in high strength concrete. Therefore, this study is intend as an mechanical properties of specimen to high heating by heating and load test machine and $700^{\circ}C$. As a result, it is willing to propose fundamental data for quick and accurate diagnosis of deteriorated concrete structure by fire damage with experiment according to the design high strength concrete.

  • PDF

A numerical analysis on the performance of buckling restrained braces at fire-study of the gap filler effect

  • Talebi, Elnaz;Tahir, Mahmood Md.;Zahmatkesh, Farshad;Kueh, Ahmad B.H.
    • Steel and Composite Structures
    • /
    • v.19 no.3
    • /
    • pp.661-678
    • /
    • 2015
  • Buckling Restrained Braces (BRB) have been widely used in the construction industry as they utilize the most desirable properties of both constituent materials, i.e., steel and concrete. They present excellent structural qualities such as high load bearing capacity, ductility, energy-absorption capability and good structural fire behaviour. The effects of size and type of filler material in the existed gap at the steel core-concrete interface as well as the element's cross sectional shape, on BRB's fire resistance capacity was investigated in this paper. A nonlinear sequentially-coupled thermal-stress three-dimensional model was presented and validated by experimental results. Variation of the samples was described by three groups containing, the steel cores with the same cross section areas and equal yield strength but different materials (metal and concrete) and sizes for the gap. Responses in terms of temperature distribution, critical temperature, heating elapsed time and contraction level of BRB element were examined. The study showed that the superior fire performance of BRB was obtained by altering the filler material in the gap from metal to concrete as well as by increasing the size of the gap. Also, cylindrical BRB performed better under fire conditions compared to the rectangular cross section.

The Effect of Low Back Pain on the EMG of Professional Golfer's Drive Swing (요통에 따른 프로 골퍼의 드라이버 스윙에 관한 근전도 분석)

  • Park, Jong-Rul
    • Korean Journal of Applied Biomechanics
    • /
    • v.15 no.4
    • /
    • pp.67-74
    • /
    • 2005
  • The purpose of this study is to compare and analyze the muscle activations between the professional golfers without low back pain symptom and the professional golfers with low back pain symptom, and so identify the stress related to golf swings, and provide the basic data to minimize the low back pain and the injury risk. Using surface electrode electromyography, we evaluated muscle activity in 6 male professional golfers during the golf drive swing. Surface electrodes were used to record the level of muscle activity in the Abdominal Oblique, Elector Spinae, Rectus Abdominis, Gluteus Maximus muscles during the golfer's swing. These signals were compared with %RVC(Reference voluntary contraction) which was normalized by IEMG(Integrated EMG). The golf swing was divided into five phases: take away, forward swing, acceleration, early follow through, late follow through. we observed patterns of trunk muscle activity throughout five phases of the golf swing. The results can be summarized as follows: RES(Right Elector Spinae) had statistically significant difference in take away phase, LGM(Left Gluteus Maximus), LRA(Left Rectus Abdominis), LOA(Left Oblique Abdominal) had statistically significant difference in forward swing phase, RES(Right Elector Spinae), RGM(Right Gluteus Maximus), ROA(Right Oblique Abdominal) had statistically significant difference in acceleration phase, RES(Right Elector Spinae), RGM(Right Gluteus Maximus) had statistically significant difference in early follow-through phase, LES(Left Elector Spinae), RGM(Right Gluteus Maximus) had statistically significant difference in late follow through phase.

Evaluation of Suitable Application of ultra high-strength Concrete to V.H Separated Placement (VH분리타설 공법의 초고강도 콘크리트 적용성 평가)

  • Kim, Hak-Young;Ki, Jun-Do;Park, Hyun;Lim, Byung Chun;Lee, Young Do;Jung, Sang Jin
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2009.11a
    • /
    • pp.23-26
    • /
    • 2009
  • Despite vigorous studies on ultra high-strength concrete in Korea, it still faces many challenges in application to on-site construction methods. This study intends to evaluate the applicability of the VH separated-pouring method which is currently used and was designed to pour ultra high-strength concrete with a design strength of 60, 100N/㎟ separately to girder and beam. When it comes to VH separated-pouring, there is a difference in the required design strength between a girder and a beam, which tends to be larger for ultra high-strength concrete. The tensile strength and cold joint at the joint end have not been commonly evaluated and thus the inevitably of its use is dependent on a structural analysis of the structural stress of reinforcement. In the study, potential problems with respect to the building material which might occur during the pouring of ultra high-strength concrete was evaluated and issues on joint surface performance, the hydration energy contained in the members, and the effects of contraction in concrete were considered as the key elements for study.

  • PDF