• 제목/요약/키워드: Motion effects

검색결과 2,971건 처리시간 0.027초

Motion and sloshing analysis for new concept of offshore storage unit

  • Ha, Mun-Keun;Kim, Mun-Sung;Paik, Bu-Keun;Park, Chung-Hum
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2000년도 추계학술대회 논문집
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    • pp.189-195
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    • 2000
  • New concept of LNG-FPSO ship with moonpool and bilge step in bottom is considered and investigated in the point of motion reduction and sloshing phenomena of the cargo and operation tanks. The cargo capacity of the ship of which principle dimensions is L x B x D x t(design) =270.0 x 51.0 x 32.32 x 13.7(m) 16K at 98% loading condition. The two moonpools and rectangular step at bilge part are setted up specially for getting the effect of motion decrease. For the motion analysis, linearized three dimensional diffraction theory with the simplified boundary conditions is used. The six-degree of freedom coupled motion responses are calculated for the LNG-FPSO ship. Viscous effects on the roll motion responses of a vessel are taken into account in this calculation program using an empirical formula suggested by Ikeda, Himeno and Tanaka is used. The case study for the moonpool size had been carried out by theoretical estimation and experimental method. For the optimization of the moonpool size and effect of the step, 9 cases of its size and with and without step are considered. From the results of calculation and experiment, it can be concluded that this designed LNG-FPSO ship have possibility to carry out her missions in the rough sea as for the owner's demand waves condition. The motion responses, especially roll motion, for the designed LNG-FPSO ship are much lower than those of another drillship and shuttle tanker and limit criterions are satisfied. For the check of the cargo tank and operation tank sizes we have performed sloshing analysis in the irregular waves which focuses on the pressure distribution on the tank wall and the time history of pressure and free surface for No.2 and No5. tanks of LNG-FPSO with chamfers. Finally we got the tank size which has no resonance and no impact pressure in all filling in the bow quartering and beam sea.

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지구운동 중심 태양계 실험 모형이 초등 예비교사와 초등학교 교사의 천문개념 변화에 미치는 효과 (The Changes of Preservice and Inservice Elementary School Teachers' Concepts of the Solar System Based upon Their Exposure to the Earth Motion Centric Solar System Model)

  • 채동현
    • 한국과학교육학회지
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    • 제24권5호
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    • pp.886-901
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    • 2004
  • 본 연구는 새롭게 고안된 "지구중심운동 태양계 실험 모형"이라는 실험모형을 통해서 초등 예비교사와 초등학교 교사의 "천문개념 변화"에 초점을 맞추었다. 전주에 소재하고 있는 전주교육대학 졸업반 학생 31명과 전북에서 근무하는 초등교사 30명을 연구 대상으로 하였다. 먼저 학생들의 사전개념을 조사하고, 이 실험 모형을 활용한 수업전후에 개념검사를 실시하였다. 검사도구는 모두 10문항으로 내행성의 운동, 내행성의 위상과 크기, 외행성의 운동, 혜성의 운동으로 구성되었다. 분석 방법은 사전 검사에서 천문개념에 대한 유년적 개념을 확인하고, 사후 검사에서 초등 예비교사와 초등학교 교사의 개념이 어떻게 변화되었는지를 조사하였다. 결과적으로 지구 운동 중심 태양계 모형이 내행성의 운동과 내행성의 위상과 크기변화, 외행성의 운동에 관한 내용에서는 올바른 과학적 개념 형성에 효과가 있었다.

선수형상이 다른 부선의 예인안정성에 관한 실험 연구 (Experimental Study on the Towing Stability of Barges Based on Bow Shape)

  • 이상;이상민
    • 해양환경안전학회지
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    • 제22권7호
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    • pp.800-806
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    • 2016
  • 예부선이 항행할 경우 부선의 회두운동으로 인하여 예선은 조종성능에 제한을 받기 때문에 부선의 회두운동을 감소시켜야 안전한 예항업무를 이행할 수 있다. 본 연구에서는 부선의 침로안정성을 향상시키기 위한 방안으로 부선의 회두운동에 영향을 미치는 항목들을 조사하기 위하여 수조실험을 실행하였다. 선수 형상에 따라 회두운동 특성이 다르게 나타나기 때문에 서로 다른 선수 형상을 지닌 부선 모델을 대상으로 스케그의 영향, 예인선속의 영향, 예인삭 길이의 영향, 브라이들의 영향에 대하여 종합적으로 분석하였다. 실험결과 스케그의 설치 위치에 의한 효과는 선수형상에 따라서 다르게 나타나고 있는 모습을 보여주고 있다. 부선의 회두운동은 부선에 연결된 예인삭의 길이가 길수록 부선의 회두가 작아짐을 알 수 있었다. 또한 예인삭만 연결한 상태보다 예인삭에 브라이들을 연결하는 것이 부선의 회두가 작아지며, 브라이들의 길이가 길어질수록 부선의 회두운동이 크게 작아짐을 알 수 있었다.

증강현실 기반의 단기간 무릎운동이 관절가동범위와 균형에 미치는 영향 - 예비연구 (The Influence of Augmented Reality based Knee Exercise in Short Period on Range of Motion and Balance - Pilot study)

  • 임종훈;유재호
    • 정형스포츠물리치료학회지
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    • 제14권2호
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    • pp.1-8
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    • 2018
  • Purpose: This study investigated the effect of the augmented reality (AR)-based knee joint short period exercise program and used a motion analyzer with a 3D camera to determine the range of motion and dynamic balance and further investigate the effects of therapeutic exercise on patients. Methods: This study used AR-based motion analysis and a Y-balance test to measure the range of motion (ROM) of each joint: the hip joint and the knee joint. After the measurements, an exercise program was applied to the subjects, using the knee motion program function, and the muscles of the quadriceps femoris and the hamstring were stretched or strengthened. Results: Our results showed knee joint extension at the dominant hip joint flexion position. While there was no significant difference (p>.05) at this position, there were significant differences in the non-dominant hips, unbalanced knee joint flexion, and superior knee joint flexion (p<.05). The Y-balance test using the non-dominant leg supported by the dominant legs showed that the absolute reach was $69.70{\pm}7.06cm$ before the exercise, and the absolute reach after the exercise was $77.56{\pm}6.09cm$ (p<.05). Conclusions: There was a significant difference when the movement of the lower limbs supported the superior limbs, and a significant difference was found in the ROM when the non-dominant side supported the dominant side. Therefore, the AR-based exercise program improves the balance of the human body and the range of motion of the joints, and research that aims to improve patients abilities should continue.

Assessment of seismic parameters for 6 February 2023 Kahramanmaraş earthquakes

  • Bilal Balun
    • Structural Engineering and Mechanics
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    • 제88권2호
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    • pp.117-128
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    • 2023
  • On February 6, 2023, Türkiye woke up with a strong ground motion felt in a wide geography. As a result of the Kahramanmaraş, Pazarcık and Elbistan earthquakes, which took place 9 hours apart, there was great destruction and loss of life. The 2023 Kahramanmaraş earthquakes occurred on active faults known to pose a high seismic hazard, but their effects were devastating. Seismic code spectra were investigated in Hatay, Adıyaman and Kahramanmaraş where destruction is high. The study mainly focuses on the investigation of ground motion parameters of 6 February Kahramanmaraş earthquakes and the correlation between ground motion parameters. In addition, earthquakes greater than Mw 5.0 that occurred in Türkiye were compared with certain seismic parameters. As in the strong ground motion studies, seismic energy parameters such as Arias intensity, characteristic intensity, cumulative absolute velocity and specific energy density were determined, especially considering the duration content of the earthquake. Based on the study, it was concluded that the structures were overloaded far beyond their normal design levels. This, coupled with significant vertical seismic components, is a contributing factor to the collapse of many buildings in the area. In the evaluation made on Arias intensity, much more energy (approximately ten times) emerged in Kahramanmaraş earthquakes compared to other Türkiye earthquakes. No good correlation was found between moment magnitude and peak ground accelerations, peak ground velocities, Arias intensities and ground motion durations in Türkiye earthquakes. Both high seismic components and long ground motion durations caused intense energy to be transferred to the structures. No strong correlation was found between ground motion durations and other seismic parameters. There is a strong positive correlation between PGA and seismic energy parameter AI. Kahramanmaraş earthquakes revealed that changes should be made in the Turkish seismic code to predict higher spectral acceleration values, especially in earthquake-prone regions in Türkiye.

혀의 자세가 경추의 관절가동범위에 미치는 영향 (The Effects of Tongue Positions on the Cervical Range of Motion)

  • 한동욱;박민희;정연희
    • 한국임상보건과학회지
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    • 제1권1호
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    • pp.29-34
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    • 2013
  • Purpose : This study was to investigate that tongue positions have effect on the cervical range of motion (ROM). Methods : 18 subjects, 20 to 25 years of age, were participated in this study. The tongue positions were neutral position, anterior protrusion, posterior protrusion, superior protrusion, inferior protrusion, left side protrusion and right side protrusion. The neck movements were right side flexion, left side flexion, right rotation and left rotation. The cervical range of motion measured by cervical range of motion instrument (CROM, C9266-49, USA). The changes were analyzed using the paired t-test. SPSSWIN (ver. 20.0) was used for data analysis and the significance level was chosen as ${\alpha}$=0.05. Results : In the lateral flexion, the angle of left lateral flexion increased in anterior protrusion(p<0.05) and right side protrusion(p<0.05) significantly. In the rotation, the angle of right rotation increased in anterior protrusion(p<0.05), posterior protrusion (p<0.05), superior protrusion(p<0.05), inferior protrusion(p<0.05), and left side protrusion (p<0.05) significantly. Conclusions : In conclusion, we found that the tongue positions affected some cervical movements.

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탄성밴드를 이용한 저항운동이 회전근개봉합술 환자의 견관절가동범위와 기능 및 통증에 미치는 효과 (Effects of Resistance Exercise using Elastic Band on Range of Motion, Function and Shoulder Pain among Patients with Rotator Cuff Repair)

  • 심재옥
    • 성인간호학회지
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    • 제28권5호
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    • pp.491-500
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    • 2016
  • Purpose: The purpose of this study was to examine the effect of resistive exercise using an elastic band on range of motion, function and shoulder pain. Methods: Forty two subjects who had rotator cuff surgery were assigned either to a treatment or a comparison group, twenty one each. Following a six week period after surgery those in the treatment group participated in resistant exercise using an elastic band for four weeks. The subjects in the comparison group did not participate in the exercise program. The goniometer measured range of motion, a modified tool measured function, and a self report numerical rating scale measured pain. The data were analyzed using $x^2$ test, Fisher's exact, t-test and the Mann-Whitney Test. Results: Although not statistically significant, there was a trend that more subjects in the treatment group had increased range of motion. There was a statistically significance among the treatment group in terms of increased function (p=.015). Further the treatment group reported less pain that those in the comparison group (p<.001). Conclusion: The findings support that resistance exercise is an effective strategy for patients with rotator cuff repair.

Experimental study on human arm motions in positioning

  • Shibata, S.;Ohba, K.;Inooka, H.
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국제학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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    • pp.212-217
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    • 1993
  • In this paper, characteristics of the motions of a human arm are investigated experimentally. When the conditions of the target point are restricted, human adjusts its trajectory and velocity pattern of the arm to fit the conditions skillfully. The purpose of this work is to examine the characteristics of the trajectory, velocity pattern, and the size of the duration in the following cases. First, we examine the case of point-to-point motion. The results are consistent with the minimum jerk theory. However, individual differences in the length of the duration can be observed in the experiment. Second, we examine the case which requires accuracy of positioning at the target point. It is found that the velocity pattern differs from the bell shaped pattern explained by the minimum jerk theory, and has its peak in the first half of the duration. When higher accuracy of the positioning is required, learning effects can be observed. Finally, to examine the case which requires constraint of the arm posture at the target point, we conduct experiments of a human trying to grasp a cup. It is considered that this motion consists of two steps : one is the positioning motion of the person in order to start the grasping motion, the other is the grasping motion of the human's hand approaching toward the cup and grasping it. In addition, two representative velocity patterns are observed : one is the similar velocity pattern explained in the above experiment, the other is the velocity pattern which has its relative maximum in the latter half of the duration.

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Effect of Joint Mobilization and Kinesio Taping on Pain, Range of Motion, and Knee Function in Patients with Knee Osteoarthritis

  • Park, Shin-Jun;Lee, Ju-Hwan
    • The Journal of Korean Physical Therapy
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    • 제28권5호
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    • pp.279-285
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    • 2016
  • Purpose: This study was conducted to investigate the effects of joint mobilization and kinesio taping on pain, range of motion and knee function in patients with knee osteoarthritis. Methods: Thirty subjects were selected and divided into three groups: group 1 was treated with joint mobilization, group 2 was treated with kinesio taping and group 3 was treated with joint mobilization and kinesio taping. Joint mobilization was performed for 20 minutes three times a week for a period of 4 weeks, after which tape was applied for the same period of time and it was not exceeded 24 hours. Pain, range of motion and knee function were then assessed to identify the effectiveness. A visual analog scale (VAS) was used for pain assessment, while active and passive range of motion (AROM, PROM) were assessed using smart phones application, and knee injury and osteoarthritis outcome score (KOOS) was used to assess knee function. Results: After intervention, the joint mobilization group and kinesio taping group showed significant improvements in VAS, AROM, PROM and KOOS (Symptom, Pain, ADL, QOL), whereas no significant difference was found in sport/recreation. The joint mobilization with kinesio taping group showed significant improvements in all items, and a significant increase was found in AROM and PROM compared to the other two groups. Conclusion: We found that joint mobilization and kinesio taping effectively improved pain, range of motion and knee function in patients with knee osteoarthritis, but that application of joint mobilization with kinesio taping was most effective.

Earthquake response of isolated cable-stayed bridges under spatially varying ground motions

  • Ates, Sevket;Soyluk, Kurtulus;Dumanoglu, A. Aydin;Bayraktar, Alemdar
    • Structural Engineering and Mechanics
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    • 제31권6호
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    • pp.639-662
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    • 2009
  • A comprehensive investigation of the stochastic response of an isolated cable-stayed bridge subjected to spatially varying earthquake ground motion is performed. In this study, the Jindo Bridge built in South Korea is chosen as a numerical example. The bridge deck is assumed to be continuous from one end to the other end. The vertical movement of the stiffening girder is restrained and freedom of rotational movement on the transverse axis is provided for all piers and abutments. The longitudinal restraint is provided at the mainland pier. The A-frame towers are fixed at the base. To implement the base isolation procedure, the double concave friction pendulum bearings are placed at each of the four support points of the deck. Thus, the deck of the cable-stayed bridge is isolated from the towers using the double concave friction pendulum bearings which are sliding devices that utilize two spherical concave surfaces. The spatially varying earthquake ground motion is characterized by the incoherence and wave-passage effects. Mean of maximum response values obtained from the spatially varying earthquake ground motion case are compared for the isolated and non-isolated bridge models. It is pointed out that the base isolation of the considered cable-stayed bridge model subjected to the spatially varying earthquake ground motion significantly underestimates the deck and the tower responses.