• Title/Summary/Keyword: strain history

Search Result 296, Processing Time 0.025 seconds

iOS-based Fitness Management System utilizing OpenWrt Server (OpenWrt 서버를 활용한 iOS기반 피트니스 케어 시스템)

  • Kye, Min-seok;Min, Joon-Ki;Yang, Seung-Eui;Park, Sang-No;Jung, Hoe-kung
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2014.10a
    • /
    • pp.687-689
    • /
    • 2014
  • Due to the development of health promotion and health care technology of smartphones paradigm from treatment to manage change, and this is increasing the fitness in time for the user. However, fitness club, users find the right exercise law-personal trainer must be costly to pay companies describes the management system is required in order to operate the high costs strain. In this paper, such as scalable servers to OpenWrt Fonera is mainly based on the client to configure the server iOS mobile sensors collect a user's movement through the history of the user's input. This data is sent to the Web and check whether the receiving system via a trainer is to record the users through weight training and to receive feedback.

  • PDF

Influence of soil model complexity on the seismic response of shallow foundations

  • Alzabeebee, Saif
    • Geomechanics and Engineering
    • /
    • v.24 no.2
    • /
    • pp.193-203
    • /
    • 2021
  • The time-history finite element analysis is usually used to evaluate the seismic response of shallow foundations. However, the literature lacks studies on the influence of the soil constitutive model complexity on the seismic response of shallow foundations. This study, thus, aims to fill this gap by investigating the seismic response of shallow foundation resting on dry silica sand using the linear elastic (LE) model, elastic-perfectly-plastic (EPP) model, and hardening soil with small strain stiffness (HS small) model. These models have been used because it is intended to compare the results of a soil constitutive model that accurately captures the seismic response of the soil-structure interaction problems (which is the HS small model) with simpler models (the LE and EPP models) that are routinely used by practitioners in geotechnical designs. The results showed that the LE model produces a very small seismic settlement value which is approximately equal to zero. The EPP model predicts a seismic settlement higher than that produced using the HS small model for earthquakes with a peak ground acceleration (PGA) lower than 0.25 g for a relative density of 45% and 0.40 g for a relative density of 70%. However, the HS small model predicts a seismic settlement higher than the EPP model beyond the aforementioned PGA values with the difference between both models increases as the PGA rises. The results also showed that the LE and EPP models predict similar trend and magnitude of the acceleration-time relationship directly below the foundation, which was different than that predicted using the HS small model. The results reported in this paper provide a useful benchmark for future numerical studies on the response of shallow foundations subjected to seismic shake.

Yield strength estimation of X65 and X70 steel pipe with relatively low t/D ratio

  • Kim, Jungho;Kang, Soo-Chang;Kim, Jin-Kook;Song, Junho
    • Steel and Composite Structures
    • /
    • v.38 no.2
    • /
    • pp.151-164
    • /
    • 2021
  • During the pipe forming process, a steel plate undergoes inelastic behavior multiple times under a load condition repeating tension and compression in the circumferential direction. It derives local reduction or increase of yield strength within the thickness of steel pipes by the plastic hardening and Bauschinger effect. In this study, a combined hardening model is proposed to effectively predict variations of yield strength in the circumferential direction of API-X65 and X70 steel pipes with relatively low t/D ratio during the forming process, which is expected to experience accumulated plastic strain of 2~3%, the typical Lüder band range in a low-carbon steel. Cyclic tensile tests of API-X65 and X70 steels were performed, and the parameters of the proposed model for the steels were calibrated using the test results. Bending-flattening tests to simulate repeated tension and compression during pipe forming were followed for API-X65 and X70 steels, and the results were compared with those by the proposed model and Zou et al. (2016), in order to verify the process of material model calibration based on tension-compression cyclic test, and the accuracy of the proposed model. Finally, parametric analysis for the yield strength of the steel plate in the circumferential direction of UOE pipe was conducted to investigate the effects of t/D and expansion ratios after O-forming on the yield strength. The results confirmed that the model by Zou et al. (2016) underestimated the yield strength of steel pipe with relatively low t/D ratio, and the parametric analysis showed that the t/D and expansion ratio have a significant impact on the strength of steel pipe.

Prevalence and risk factors of low back and pelvic pain in women with rectus abdominis diastasis: a multicenter retrospective cohort study

  • Yuan, Sue;Wang, Honghong;Zhou, Jie
    • The Korean Journal of Pain
    • /
    • v.35 no.1
    • /
    • pp.86-96
    • /
    • 2022
  • Background: To explore the association between low back pain (LBP) and pelvic pain (PP) and rectus abdominis diastasis (RAD) in postpartum women and identify the characteristics and risk factors. Methods: Women diagnosed with RAD and a history of labor and delivery, between 2009 and 2018, were identified from six hospitals within the Partners Healthcare System. Univariate and multivariable binary logistic regression analyses were used to identify the risk factors associated with pain. Results: Age at onset of RAD in the non-cesarean delivery group was earlier than those in cesarean delivery (CD) group (P = 0.017). Women who underwent CD demonstrated 4.5 times greater risk of RAD than those who had no CD exposure. The cumulative composition ratio of LBP at every age stage of the period from 8 years pre-first delivery to 8 years post-first delivery was significantly higher than the other five conditions (RAD, umbilical hernia, PP, depressive disorder [DD], and strain of muscle, fascia, and tendon [SMFT]) (P for trend < 0.001). Women with DD, SMFT, and PP were more likely to have LBP (odds ratio [OR] = 1.91, 95% confidence interval [CI] 1.06 to 3.47, P = 0.032; OR = 4.50, 95% CI 1.64 to 12.36, P = 0.003; OR = 2.14, 95% CI 1.17 to 3.89, P = 0.013; respectively). Conclusions: In postpartum women with RAD, DD, SMFT, and PP were found to be risk factors contributing to the development of LBP. Race and LBP also played roles in the development of PP.

The effectiveness of position of coupled beam with respect to the floor level

  • Yasser Abdal Shafey, Gamal;Lamiaa K., Idriss
    • Coupled systems mechanics
    • /
    • v.11 no.6
    • /
    • pp.557-586
    • /
    • 2022
  • In spite of extensive testing of the individual shear wall and the coupling beam (CB), numerical and experimental researches on the seismic behavior of CSW are insufficient. As far as we know, no previous research has investigated the affectations of position of CB regarding to the slab level (SL). So, the investigation aims to enhance an overarching framework to examine the consequence of connection positions between CB and SL. And, three cases have been created. One is composed of the floor slab (FS) at the top of the CB (FSTCB); the second is created with the FS within the panel depth (FSWCB), and the third is employed with the FS at the bottom of the CB (FSLCB). And, FEA is used to demonstrate the consequences of various CB positions with regard to the SL. Furthermore, the main measurements of structure response that have been investigated are deformation, shear, and moment in a coupled beam. Additionally, wall elements are used to simulate CB. In addition, ABAQUS software was used to figure out the strain distribution, shear stress for four stories to further understand the implications of slab position cases on the coupled beam rigidity. Overall, the findings show that the position of the rigid linkage among the CB and the FS can affect the behavior of the structures under seismic loads. For all structural heights (4, 8, 12 stories), the straining actions in FSWCB and FSLCB were less than those in FSTCB. And, the increases in displacement time history response for FSWCB are around 16.1-81.8%, 31.4-34.7%, and 17.5% of FSTCB.

Ground response analysis of a standalone soil column model for IDA of piled foundation bridges

  • Hazem W. Tawadros;Mousa M. Farag;Sameh S.F. Mehanny
    • Earthquakes and Structures
    • /
    • v.24 no.4
    • /
    • pp.289-301
    • /
    • 2023
  • Developing a competent soil-bridge interaction model for the seismic analysis of piled foundation bridges is of utmost importance for investigating the seismic response and assessing fragility of these lifeline structures. To this end, ground motion histories are deemed necessary at various depths along the piles supporting the bridge. This may be effectively accomplished through time history analysis of a free-field standalone soil column extending from bedrock level to ground surface subjected to an input bedrock motion at its base. A one-dimensional site/ground response analysis (vide one-directional shear wave propagation through the soil column) is hence conducted in the present research accounting for the nonlinear hysteretic behavior of the soil stratum encompassing the bridge piled foundation. Two homogeneous soil profiles atop of bedrock have been considered for comparison purposes, namely, loose and dense sand. Analysis of the standalone soil column has been performed under a set of ten selected actual bedrock ground motions adopting a nonlinear time domain approach in an incremental dynamic analysis framework. Amplified retrieved PGA and maximum soil shear strains have been generally observed at various depths of the soil column when moving away from bedrock towards ground surface especially at large hazards associated with high (input) PGA values assigned at bedrock. This has been accompanied, however, by some attenuation of the amplified PGA values at shallower depths and at ground surface especially for the loose sand soil and particularly for cases with higher seismic hazards associated with large scaling factors of bedrock records.

Cyclic loading test for concrete-filled hollow PC column produced using various inner molds

  • Chae-Rim Im;Sanghee Kim;Keun-Hyeok Yang;Ju-Hyun Mun;Jong Hwan Oh;Jae-Il Sim
    • Steel and Composite Structures
    • /
    • v.46 no.6
    • /
    • pp.793-804
    • /
    • 2023
  • In this study, cyclic loading tests were conducted to assess the seismic performance of cast-in-place (CIP) concrete-filled hollow core precast concrete columns (HPCC) constructed using steel ducts and rubber tubes. The outer shells of HPCC, with a hollow ratio of 47%, were fabricated using steel ducts and rubber tubes, respectively. Two combinations of shear studs & long threaded bars or cross-deformed bars & V-ties were employed to ensure the structural integrity of the old concrete (outer shell) and new CIP concrete. Up to a drift ratio of 3.8%, the hysteresis loop, yielding stiffness, dissipated energy, and equivalent damping ratio of the HPCC specimens were largely comparable to those of the solid columns. Besides the similarities in cyclic load-displacement responses, the strain history of the longitudinal bars and the transverse confinement of the three specimens also exhibited similar patterns. The measured maximum moment exceeded the predicted moment according to ACI 318 by more than 1.03 times. However, the load reduction of the HPCC specimen after reaching peak strength was marginally greater than that of the solid specimen. The energy dissipation and equivalent damping ratios of the HPCC specimens were 20% and 25% lower than those of the solid specimen, respectively. Taking into account the overall results, the structural behavior of HPCC specimens fabricated using steel ducts and rubber tubes is deemed comparable to that of solid columns. Furthermore, it was confirmed that the two combinations for securing structural integrity functioned as expected, and that rubber air-tubes can be effectively used to create well-shaped hollow sections.

Analysis of Pull-out Behavior of Tunnel-type Anchorage for Suspended Bridge Using 2-D Model Tests and Numerical Analysis (2차원 모형실험 및 수치해석을 통한 현수교 터널식 앵커리지의 인발거동 특성 분석)

  • Seo, Seunghwan;Park, Jaehyun;Lee, Sungjune;Chung, Moonkyung
    • Journal of the Korean Geotechnical Society
    • /
    • v.34 no.10
    • /
    • pp.61-74
    • /
    • 2018
  • In this study, the pull-out behavior of tunnel type anchorage of suspension bridges was analyzed based on results from laboratory size model tests and numerical analysis. Tunnel type anchorage has found its applications occasionally in both domestic and oversea projects, therefore design method including failure mode and safety factor is yet to be clearly established. In an attempt to improve the design method, scaled model tests were conducted by employing simplified shapes and structure of the Ulsan grand bridge's anchorage which was the first case history of its like in Korea. In the model tests, the anchorage body and the surrounding rocks were made by using gypsum mixture. The pull-out behavior was investigated under plane strain conditions. The results of the model tests showed that the tunnel type anchorage underwent wedge shape failure. For the verification of the model tests, numerical analysis was carried out using ABAQUS, a finite element analysis program. The failure behavior predicted by numerical analysis was consistent with that by the model tests. The result of numerical analysis also showed that the effect of Poisson's ratio was negligible, and that a plugging type failure mode could occur only when the strength of the surrounding rocks was 10 times larger than that of anchorage body.

The clinical observation of patient with Headache Treated by Trigger point acupuncture therapy (발통점(發通點)을 이용(利用)한 두통(頭痛) 치험례(治驗例) 보고(報告))

  • Lee Seung-Yeon;Kim Jang-Hyun
    • The Journal of Pediatrics of Korean Medicine
    • /
    • v.12 no.1
    • /
    • pp.133-143
    • /
    • 1998
  • Myofascial pain syndrome is one of the pain syndrome resulted from myofascia which covered muscles and clinically characteristic feature by sensitive trigger point in skeletal muscles and referred pain reactivated by stimulating each trigger point. The origin of headache are local lesion such as head, chest, abdominal organ, systemic lesion with fever or in toxic state. the other factors are consciousness, personality, anxiety, depression, which cause muscle strain in physiological environment. The Oriental Medical therapy for headache has herb medication and acupuncture. especially acupuncture therapy has not only classical systemic acupuncture(體鍼) but also neo-acupuncture(新鍼) such as commonly using auricular acupuncture(耳鍼) and manual acupuncture (手鍼), recently trigger point acupuncture is used. The author analyzed 27 cases of patient with headache treated by trigger point acupuncture therapy in Dong-yu Oriental Medical Hospital from March 1st 1997 to February 28th 1998. The following results were obtained. 1. The sex ratio of the female was 59.26%(16 cases) and male was 40.74%(11 cases), the ratio of high school student was 62.96%(17cases) as first. 2. The headache duration ratio of 2-3 years was 37.04%(10 cases) as first, 1-2 years was 25.93%(7 cases) as second. 3. The portion ratio of whole headache was 33.33%(9 cases) as first, lateral headache was 29.63%(8 cases) as second 4. The combined symptoms ratio of anorexia was 40.74%(11 cases) as first, fatigue was 33.33%(9 cases) as second, neck stiffness and dizziness was each 25.93%(7 cases) as third. 5. The therapeutic duration ratio of below 1 week was 29.63%(8 cases) as first, 2-3 weeks was 22.22%(6 cases) as second, 1-2 weeks and 3-4 weeks was each 18.52%(5 cases) as third. 6. The ratio of family history was 11 cases(40.74%). mother with headache was 6 cases, father was 3 cases, and brothers & sisters was 2 cases. 7. The herb medication ratio of Chungsanggyuntongtang(淸上?痛湯) was 37.04%(10 cases), Kamiondamtang(加味溫膽湯) was 22.22%(6 cases), Hyangsapyunguisan(香砂平胃散) was 18.25%(5 cases) etc. 8. The remedial effect ratio of good was 25.93%(7 cases), fair was 48.15%(13 cases), not improved was 7.41%(2 cases), side effect was 3.70%(1 cases), and unknown was 14.81%(4 cases).

  • PDF

A Case of Disseminated Mycobacterium bovis Infection after BCG Vaccination (Tokyo strain) in an Apparently Immunocompetent Infant (면역기능이 정상인 영아에서 동경주 BCG 백신 접종 후 발생한 파종성 Mycobacterium bovis 감염 1예)

  • Paik, Ji Yeun;Choi, Jae Hong;Kim, Min Kyung;Choi, Eun Hwa;Lee, Hoan Jong;Park, Kyoung Un
    • Pediatric Infection and Vaccine
    • /
    • v.18 no.1
    • /
    • pp.91-96
    • /
    • 2011
  • Bacille Calmette-Gu$\acute{e}$rin (BCG) vaccine is a live attenuated vaccine derived from Mycobacterium bovis. Frequent complications after BCG vaccination are localized ulcer formation and regional lymphadenitis, but there could be rarely severe systemic reactions to BCG vaccine such as osteomyelitis and disseminated BCG infection. Although disseminated BCG infection can be complicated in infants with underlying immunodeficiency after BCG vaccination, it is very unlikely to develop in immunocompetent infants or children. We report a 13-month-old infant who presented with fever, skin nodules, and multiple enlarged lymph nodes 5 months following BCG vaccination. She was diagnosed with disseminated BCG infection by PCRconfirmed M. bovis BCG infection at ${\geq}$2 anatomical sites beyond the region of vaccination. The patient showed no obvious evidence of immunodeficiency as judged on the basis of previous disease history, plasma immunoglobulin levels, B and T lymphocytes counts in peripheral blood, DHR (dihydrorhodamine 123 fluorescence) test and HIV test. She started antituberculous treatment with isoniazid and rifampin, and now, apparently her symptoms have been improved.