• Title/Summary/Keyword: vertical joints

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Study on the Correlation between Analysis and Experiment for the Nonlinear Behavior of large Panel Precast Concrete Subassemblage (P.C 대형판 부분구조의 비선형 거동에 관한 실험과 해석 비교연구)

  • 김성호;이한선;이병해
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1990.10a
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    • pp.47-54
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    • 1990
  • Under external loads, large panel structures behave quite differently from monolithic wall structures, because of the distinct planes of weakness in the horizontal and vertical joints between panels. Study on the ultimate load and the failure mode of the large panel structures under extream lateral loads is therefore important. The purpose of this study is to predict the nonlinear behavior of the structure using the general purpose nonlinear computer program 'ANSR' being based on the quasi-static test results of the large panel structure(full scale in two story) and to examine the distribution and change mode of the internal forces which can not be obtained in the test.

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Field Experiment Generating Shear Waves by Using french Method (트렌치를 이용한 S 파 발생 현장실험)

  • Lee, Doo-Sung;Kim, Hyoun-Gyu
    • Geophysics and Geophysical Exploration
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    • v.2 no.4
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    • pp.209-214
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    • 1999
  • A field experiment generating shear waves by trench method was conducted at two places in Taejun area. We were able to separate the P- and S-waves by summing and subtracting the vertical and horizontal component of the data recorded at a three component downhole geophone in the borehole. The analysis of the records revealed that the shear waves were polarized to NS and EW directions. The faster shear waves were polarized to NS direction. The NS direction generally agrees with the dominant joints direction observed from the cores collected from the borehole.

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Comparison of Cervical Musculoskeletal Kinematics in Two Different Postures of Primate During Voluntary Head Tracking

  • Park, Hyeonki;Emily Keshner;Barry W. Peterson
    • Journal of Mechanical Science and Technology
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    • v.17 no.8
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    • pp.1140-1147
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    • 2003
  • We have examined the effect on neck-muscle activation of altering whole body posture. A Rhesus monkey (Macaca mulatta) was trained to produce sinusoidal (0.25 Hz) head tracking movements in the sagittal plane when seated with trunk and head vertical or while standing in the quadrupedal position. Video-fluoroscopic images of cervical vertebral motion, and electromyographic (EMG) responses were recorded simultaneously. Results demonstrated that vertebral motion varied with body posture, occurring synchronously between all joints in the upright position and primarily at skull-$C_1$ when in the quadrupedal position. Muscle EMG activation was significantly greater (P<0.001) in the quadrupedal position than when upright for all muscles except semispinalis cervicis. Peak activation of all the muscles occurred prior to peak head extension in the quadrupedal position, suggesting synchronous activity between muscles. Data suggest that, when upright, muscles were activated in functional groupings defined by their anatomical arrangement. In the quadrupedal position, gravity acting on the horizontally oriented head produced greater activation and a collective response of the muscles.

Study on the Piezoelectric Bender Actuator for Small Walking Robots

  • Park, Min Ho;Park, Jong Man;Song, Chi Hoon
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.33 no.4
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    • pp.276-280
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    • 2020
  • A linear piezoelectric actuator that utilizes the elliptical motion of the two tips of the actuator is proposed. This device is easy to fabricate owing to its simple structure, consisting of three piezo ceramic benders and is suitable for use in micro robotic applications. A π-shaped structure, which was composed of four piezo ceramic benders, was constructed. Two of the benders were positioned on the center of the actuator, and the joints were attached at the ends of the cantilever. The other two benders were positioned on the side of the actuator and were attached between the joint and the tips. The actuator structure was designed to obtain the first bending mode of the horizontal vibration and the vertical vibration at the same frequency, resulting in elliptical motions at the tips. When two sinusoidal wave voltages with a 90-degree phase difference were applied to the two pairs of the actuator benders, elliptical motions were obtained at the tips. The driving characteristics of the prototype actuator were then measured using a laser doppler vibrometer.

A Biomechanical Analysis According to Passage of Rehabilitation Training Program of ACL Patients (전방십자인대 수술자의 재활트레이닝 경과에 따른 운동역학적 분석)

  • Jin, Young-Wan
    • Korean Journal of Applied Biomechanics
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    • v.23 no.3
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    • pp.235-243
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    • 2013
  • The purpose of this study was to analyse scientific according to period of rehabilitation training of ACL patients. ACL patients seven subjects participated in this study. Gait (1.58 m/sec) analysis was performed by using a 3-D Cinematography, a Zebris system and a electromyograph system. The data were analyzed by paired t-test. The joint angles were recorded from the ankle, knee, hip joints. Peak max dorsi-flexion and peak max plantar-flexion identified significant differences (p<0.05). Another angles were no significant difference. Vertical force (Fz) and max pressure variables improved 6 month RTP better than 3 month RTP. EMG were collected from 4 muscles (rectus femoris, biceps femoris, gastrocnemius, tibialis anterior) with surface electrides in gait system. EMG signals were rectified and smoothed data. EMG signas were no significant difference but they also improved 6 month RTP better than 3 month RTP. More research is necessary to determine exactly what constitutes optimal rehabilitation training period for ACL patients.

Constructional Verification Evaluation for Securing the Field Quality of Composite Membrane Waterproofing Material (멤브레인 복합 방수재의 현장품질 안정성 확보를 위한 시공성 실증 평가 연구)

  • Kim, Meong-Ji;Lee, Sang-Wook;Kim, Soo-Yeon;Oh, Sang-Keun
    • Journal of the Korea Institute of Building Construction
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    • v.21 no.1
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    • pp.87-95
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    • 2021
  • In this study, seven companies(A~G) designated as new construction technology selected and evaluated KS F 2622: Method of test for performance evaluation of membrane roofing systems that are similar to field application conditions. As a result of the test, it was confirmed that although all test specimens exceeded KS standards in the basic physical, it was difficult to obtain field quality performance in weak areas such as joints and vertical parts of the adhesive coating method in water-tightness, sagging resistance, swelling resistance tests except for fatigue(crack behavior) tests.

Kinetic gait analysis in a small sized dog with congenital shoulder luxation (소형견의 선천성 어깨관절 탈구에 관한 운동역학적 보행 분석)

  • ShinHo Lee;Chung Hui Kim;Jae-Hyeon Cho
    • Korean Journal of Veterinary Service
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    • v.46 no.2
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    • pp.175-179
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    • 2023
  • This study was conducted to find out the compensation strategy through kinetic gait analysis by comparing dog with congenital luxation of the shoulder joint and normal dog. Ground reaction forces were recorded for all limbs while normal poodle dog and poodle dog with shoulder joint luxation was allowed to walk on an instrumented platform. The dogs were evaluated for maximal vertical force (MVF), body load distribution (BLD), and symmetry index (SI). The MVF was increased in the contralateral forelimb of luxated shoulder joint. The SI was also increased in a dog with dislocated shoulder joints in the forelimbs. For BLD, the maximum load distribution increased centrally, but the total load distribution decreased in the ipsilateral forelimb paw. In contrast, total load distribution was increased in the contralateral forelimb paw. During forelimb lameness, changes in weight-bearing load showed compensatory load redistribution. These biomechanical changes may lead to changes in the musculoskeletal system in a dog with luxated shoulder.

Detailed Analysis of Vertical Connector in Modular Roadway Slab Under Temperature and Lifting Loading (온도하중과 인양하중에 영향을 받는 모듈러 도로 슬래브 수직연결부의 상세해석)

  • Kim, WooSeok;Nam, Jeonghee;Min, Geunhyeong;Kim, Kyeongjin;Lee, Jaeha
    • Journal of the Korea Concrete Institute
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    • v.28 no.5
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    • pp.509-517
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    • 2016
  • In terms of bridge construction, the concrete deck slab is weak members compared to beam members of the bridge supports. Deck slabs must be sound to support and distribute vehicle loads. If slabs are not enough to support the loads, it should be replaced. Bridge deck replacement has been an important industry over the world since the construction is simplified to shorten construction time and to save construction costs. Slab module provides a quickly, easily and reliably construction method in order to avoid high cost and minimum traffic disruption. in addition, slab module shows high reliability since they are factory products. However, slab module should be considered in the performance under various loads. In this study, structural analysis is performed to evaluate the performance of slab module under vehicle loads and temperature loads. Spiral rebar is also utilized around the vertical joints to improve the structural integrity under the lifting loads. In order to confirm the weak area of slab module for the lift condition, numerical analysis has been performed.

Biomechanical Comparison of Soft Tissue Reconstructions in the Treatment of Medial Patellar Luxation in Dogs

  • Kim, Sang-Yeoun;Moon, Hee-Sup;Park, Sung-Guon;Hong, Sung-Jin;Choi, Hee-Bok;Hwang, Tae-Sung;Lee, Hee-Chun;Hwang, Yong-Hyun;Lee, Jae-Hoon
    • Journal of Veterinary Clinics
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    • v.34 no.6
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    • pp.414-419
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    • 2017
  • The present study aimed to document the biomechanical findings of soft tissue reconstruction surgeries for the treatment of medial patellar luxation in dogs. Stifle joints (n = 12) from dogs weighing 4.1-8.4 kg were used in this study. The following soft tissue reconstruction techniques used for the treatment of medial patellar luxation were selected for this study: vastus medialis release, medial retinacular release, and capsule release for medial realignment (n = 6), and retinacular imbrication and anti-rotational suture for lateral realignment (n = 6). A 5-kg traction using an electronic scale was applied at $45^{\circ}C$ laterally for medial realignment and medially for lateral realignment. Fluoroscopic imaging was used to measure the length of patellar displacement (LPD) in each technique. Among medial realignment techniques, capsule release had the highest horizontal LPD; vastus medialis release had significantly higher horizontal LPD than medial retinacular release. Vastus medialis release had the smallest increase statistically in vertical LPD, and vertical LPD did not differ significantly between medial retinacular and capsule release. Among lateral realignment techniques, the horizontal LPD was significantly higher in anti-rotational suture with retinacular imbrication than in retinacular imbrication alone, but the vertical LPD did not differ significantly between the two groups. Our findings indicated that vastus medialis release could decrease the medial tension on the patella without inducing patellar instability in dogs. Both medial retinacular and capsule release could increase patellar instability; moreover, medial retinacular release does not decrease the medial tension on the patella. Antirotational suture with retinacular imbrication provides more lateral tension than retinacular imbrication alone.

Full Mouth Rehabilitation (완전 구강 회복술)

  • Lee, Seung-Kyu;Lee, Sung-Bok;Kwon, Kung-Rock;Choi, Dae-Gyun
    • Journal of Dental Rehabilitation and Applied Science
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    • v.16 no.3
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    • pp.171-185
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    • 2000
  • The treatment objectives of the complete oral rehabilitation are : (1) comfortably functioning temporomandibular joints and stomatognathic musculature, (2) adherence to the basic principle of occlusion advocated by Schuyler, (3) anterior guidance that is in harmony with the envelope of function, (4) restorations that will not violate the patient's neutral zone. There may be many roads to achieving these objectives, but they all convey varing degrees of stress and strain on the dentist and patient. There are no "easy" cases of oral rehabilitation. Time must be taken to think, time must be taken to plan, and time must be taken to perform, since time is the critical element in both success and failure. Moreover, a systematized and integrated approach will lead to a prognosis that is favorable and predictable. This approach facilitates development of optimum oral function, comfort, and esthetics, resulting in a satisfied patient. Such a systematized approach consists of four logical phase : (1) patient evaluation, (2) comprehensive analysis and treatment planning, (3) integrated and systematic reconstruction, and (4) postoperative maintenance. Firstly, we must evaluate the mandibular position. The results of a repetitive, unstrained, nondeflective, nonmanipulated mandibular closure into complete maxillomandibular intercuspation is not so much a "centric" occlusion as it is a stable occlusion. Accordingly, we ought to concern ourselves less with mandibular centricity and more with mandibular stability, which actually is the relationship we are trying to establish. The key to this stability is intercuspal precision. Once neuromuscular passivity has been achieved during an appropriate period of occlusal adjustment and provisionalization, subsequent intercuspal precision becomes the controlling factors in maintaining a stable mandibular position. Secondly, we must evaluate the planned vertical dimension of occlusion in relationship to what may now be an altered(generally diminished), and avoid the hazard of using such an abnormal position to indicate ultimate occlusal contacting points. There are no hard and fast rules to follow, no formulas, and no precise ratios between the vertical dimension of occlusion. Like centric relation, it is an area, not a point.

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