• 콘크리트학회논문집
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• 제14권5호
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• pp.759-765
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• 2002

등가하중법은 프리스트레싱 텐던의 영향을 구조물에 작용하는 외력으로서 고려하는 것으로, 프리스트레싱의 효과를 명확히 하고 해석을 단순화시켜주는 유력한 방법론이다. 본 연구에서는 등가하중법의 관점에서 원형탱크 벽체의 원환텐던 및 수직텐던의 배치가 구조물에 미치는 영향을 이론적으로 분석하였으며, 관련된 설계 시방서에서 규정하고 있지는 않지만 실구조물에서 적지 않은 영향을 미칠 수도 있는 사항들에 대해 고찰하였다. 원환텐던의 편심배치시 텐던의 직선이동의 원리가 성립하므로 어떠한 편심배치에 대해서도 구조거동은 크게 달라지지 않을 것으로 사료된다. 또한, 기존의 수직텐던의 설계 및 해석에 있어서 편심배치에 의한 모멘트 효과를 잘못 산정한 예에 대해 올바른 해석법을 제시하였다. 일반적으로 수직텐던의 편심배치는 구조적으로 큰 효과가 있다고 보기는 힘든 것으로 사료된다. 수직텐던과 관련하여 프와송비의 효과나 절곡부위의 영향이 흔히 간과되어 왔으나, 예제의 분석결과 때로는 원형탱크의 구조거동에 적지 않은 영향을 미칠수도 있다고 판단된다.

• 한국운동역학회지
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• 제25권2호
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• pp.175-182
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• 2015

Objective : The purpose of this study was to investigate difference in fascicle behavior of the medial gastrocnemius during the locomotion with varying intensities, such as gait and one-legged and two-legged vertical jumping. Methods : Six subjects (3 males and 3 females; age: $27.2{\pm}1.6yrs.$, body mass: $62.8{\pm}9.8kg$, height: $169.6{\pm}8.5cm$) performed normal gait (G) at preferred speed and maximum vertical jumping with one (OJ) and two (TJ) legs. While subjects were performing the given tasks, the hip, knee and ankle joint motion and ground reaction force was monitored using a 8-infrared camera motion analysis system with two forceplates. Simultaneously, electromyography of the triceps surae muscles, and the fascicle length of the medial gastrocnemius were recorded using a real-time ultrasound imaging machine. Results : Comparing to gait, the kinematic and kinetic parameters of TJ and OJ were found to be significantly different. Along with those parameters, change in the medial gastrocnemius (MG) muscle-tendon complex (MTC) length ($50.57{\pm}6.20mm$ for TJ and $44.14{\pm}5.39mm$ for OJ) and changes in the fascicle length of the MG ($18.97{\pm}3.58mm$ for TJ and $20.31{\pm}4.59mm$ for OJ) were observed. Although the total excursion of the MTC and the MG fascicle length during the two types of jump were not significantly different, however the pattern of length changes were found to be different. For TJ, the fascicle length maintained isometric longer during the propulsive phase than OJ. Conclusion : One-legged and two-legged vertical jumping use different muscle-tendon interaction strategies.

• Structural Engineering and Mechanics
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• 제72권3호
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• pp.355-366
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• 2019

Self-centering wall (SCW) is a resilient and sustainable structural system which incorporates unbonded posttensioning (PT) tendons to provide self-centering (SC) capacity along with supplementary dissipators to dissipate seismic energy. Hysteretic energy dissipators are usually placed at two sides of SCWs to facilitate ease of postearthquake examination and convenient replacement. To achieve a good prediction for the skeleton curve of the wall, this paper firstly developed an analytical investigation on lateral load responses of self-centering walls with distributed vertical dampers (VD-SCWs) using the concept of elastic theory. A simplified method for the calculation of limit state points is developed and validated by experimental results and can be used in the design of the system. Based on the analytical results, parametric analysis is conducted to investigate the influence of damper and tendon parameters on the performance of VD-SCWs. The results show that the proposed approach has a better prediction accuracy with less computational effects than the Perez method. As compared with previous experimental results, the proposed method achieves up to 60.1% additional accuracy at the effective linear limit (DLL) of SCWs. The base shear at point DLL is increased by 62.5% when the damper force is increased from 0kN to 80kN. The wall stiffness after point ELL is reduced by 69.5% when the tendon stiffness is reduced by 75.0%. The roof deformation at point LLP is reduced by 74.1% when the initial tendon stress is increased from $0.45f_{pu}$ to $0.65f_{pu}$.

• 대한두경부종양학회지
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• 제17권2호
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• pp.198-204
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• 2001

Background and Objectives: As the laryngopharyngeal cancer is usually found at a advanced stage, it is difficult to get a wide surgical margin that preserves functional aspect and that is oncologically safe simultaneously. There were many operative technique to fulfill this principle, but none were satisfactory. Recently there were some reports about glottic and pharyngeal reconstruction using radial forearm free flap(RFFF) with palmaris longus tendon, which provided satisfactory oncologic and functional results. We attempted to perform this technique and to test usefulness at patients of laterally localized laryngopharyngeal tumor. Materials and Methods: Three patients were reconstructed glottis and pharynx using radial forearm free flap with palmaris longus tendon. Two hypopharyngeal cancer (T2N0M0) patients were performed wide vertical hemilaryngopharyngectomy and one supraglottic cancer(T2N0M0) patient was performed horizontovertical laryngopharyngectomy. Deglutitional function was evaluated with modified barium swallow and speech function was evaluated by speech pathologist. Results: Mean follow-up time was 29.3 months. There were no cancer recurrence. Their speech was satisfy-actory at social communication and oral feeding. They all have a complete oral nutrition from 26 days to 53 days. Decanulation time was from 71 days to 30 months. Conclusion: Glottic and pharyngeal reconstruction with radial forearm free flap could be accepted as a promising technique which offers a wide resection margin but satisfactory functional result in lateralized laryngohypopharyngeal cancer patients.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 추계 학술논문 발표대회
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• pp.167-168
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• 2012

Analysis on structural effects which are reduction of friction coefficient and increase of tendon area by HDPE greased and large size strand in post-tensioning system of reactor containment building was carried out. Effective ratio of tendon force increases 67% to 83% by HDPE greased strand and vertical, horizontal internal section forces increased maximum 51%, 41% respectively. Tendon quantity could be reduced 30% by large size and HDPE greased strand that can maintain safety of ultimate internal pressure same as at present.

• 콘크리트학회논문집
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• 제21권1호
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• pp.105-116
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• 2009

철근콘크리트구조는 경제성이 뛰어나 가장 널리 사용되는 부재이지만, 인장응력에 취약하고 콘크리트의 자중이 커서 처짐 제어가 어려운 단점이 있다. 이에 비해 프리스트레스트 콘크리트구조는 콘크리트구조의 단점을 극복할 수 있는 효율적인 방법으로 긴장재의 배치 형태와 긴장재량에 따라서 부재의 처짐을 제어할 수 있다. 프리스트레스 보강된 부재에서 긴장재 변곡점의 위치는 부재의 처짐 제어 및 모멘트 감소 효율을 크게 할 수 있는 형태로 설치되어야 한다. 따라서 이 연구에서는 연속부재에 설치되는 긴장재의 경계조건을 만족시키는 긴장재의 곡선식을 다항식으로 유도하고, 자연적인 곡선 형상을 유지할 수 있는 임의의 변곡점 위치에 따른 긴장재의 곡선식을 통하여 긴장력의 수직 분력을 계산하였다. 또한, 유도된 고차항을 가진 수직분력식을 등가의 등분포 하중으로 변환하여 처짐 산정시 적용성을 높였으며, 연속 슬래브에서 긴장재가 배치되어있을 경우 기둥열에서부터 긴장재까지 떨어진 거리에 따라 처짐 및 모멘트에 대한 긴장재의 영향을 반영하였다. 제안된 방법으로 긴장재가 없는 슬래브와 긴장재로 보강된 경우에 대한 처짐을 계산하여 적용성을 검토하였으며, 긴장재에 의한 처짐 제어 효과를 정량적으로 산출하였다.

• 대한두경부종양학회지
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• 제21권1호
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• pp.35-41
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• 2005

Wide vertical hemilaryngopharyngectomy with immediate glottic and pharyngeal reconstruction using a radial forearm free flap is reported in 1991 by Chantrain et al. This procedure was designed for the preservation of healthy hemilarynx and resection of pharynx with safe oncological margin in especially piriform sinus cancer or supraglottic cancer invading the hypopharynx. In the original paper, they used palmaris longus tendon for reconstruction of neoglottis. In other groups, they used rib cartilage instead of palmaris longus tendon. In this paper, we report two cases of piriform sinus cancer patients who treated with wide vertical hemilaryngectomy with radial forearm free flap reconstruction. In one case, the operation was performed as Chantrain et al described. But in another case, the ipsilateral forearm was impossible due to the positive Allen's test. So the contralateral forearm flap and rib cartilage graft was done. This reconstructive technique make large resection possible. As the dissection of thyroid cartilage and lateral displacement makes direct visualization and manipulation of piriform sinus lesions, sufficient resection margin in lateral and inferior pharyngeal wall cab be obtained.

• 대한토목학회논문집
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• 제32권5A호
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• pp.289-297
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• 2012

본 연구는 부착식 PSC 텐던의 응력파 속도를 계측하여 텐던에 도입된 긴장응력을 추정 할 수 있는 실험식을 제안한다. 실용적 실험식의 도출을 위하여 도입 긴장력이 다른 다수의 PSC시험체가 제작되었으며, 다양한 조건에서 종진동 실험이 반복 수행되었다. 도입 응력과 응력파 속도 사이의 관계에 영향을 미칠 수 있는 온도, 길이 및 텐던의 개수 등이 영향인자로 고려되었으며, 상사의 법칙을 적용하여 무차원 실험식이 도출 되었다. 제안 기법의 현장 적용성 검증은 실제 발전소 격납건물에 설치된 수직텐던에 대하여 수행되었다. 제안식을 이용하여 추정된 긴장응력은 텐던의 설계응력과 유사하다.

• 대한물리의학회지
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• 제11권4호
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• pp.11-17
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• 2016

PURPOSE: There are several standard interventions for managing Achilles tendinitis, including eccentric exercise and calf muscle stretches, orthoses, electrotherapy, and taping. However, no study has determined the effect of non-elastic taping on deloading the Achilles tendon while vertical jumping. Therefore, this study determined the effect of non-elastic taping on ankle dorsiflexion and the triceps surae muscle activity while vertical jumping in healthy subjects. METHODS: The study recruited 17 participants. A motion analysis system was used to measure the angle of ankle dorsiflexion and wireless surface electromyography was used to measure the soleus and gastrocnemius activities while vertical jumping. Non-elastic taping was applied on randomized leg side. All subjects performed maximal effort vertical jumps without and with non-elastic taping, with three trials for each condition. The mean peak dorsiflexion and muscle activities during the three trials were calculated and paired t-tests were used to compare the mean values without and with non-elastic taping. Significance was defined as (p<.05). RESULTS: The maximum angle of ankle dorsiflexion and activity of the gastrocnemius muscle decreased significantly when non-elastic tape was applied (p<.05), while there was no significant difference in the soleus activity between no-taping and taping (p>.05). CONCLUSION: We introduce non-elastic taping as a method to decrease maximum ankle dorsiflexion and gastrocnemius activity while vertical jumping.

• 한국운동역학회지
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• 제16권3호
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• pp.9-18
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• 2006

These studies show that I applied to functional insole (a specific S company) for minimizing shocks and sprain people's ankle arising from running. How to an effect on human body which studied a kinematics and kinetics from 10 college students during experiments. This study imposes several conditions by barefoot, normal running shoes and put functional insole shoes ran under average $2.0{\pm}0.24$ meter per second by motion analysis, ground reaction force and electromyography that used to specific A company. First of all, Motion analysis was caused by Achilles tendon angle, Angle of the lower leg, Angle of the knee, Initial sole angle and Barefoot angle. Second, Contact time, Vertical impact force peak timing, Vertical active force and Active force timing, and Maximum loading rate under impulse of first 20 percent and Value of total impulse caused Ground reaction force. Third. The tendon fo Quadriceps femoris, Biceps femoris, Tibialis anterior and gastronemius medials caused. electromyography. 1. Ground reaction force also showed that statically approximates other results from impact peak timing (p.001), Maximum loading rate(p<.001), Maximum loading rate timing (p<.001) and impulse of first 20 percent (p<.001). 2 Electromyography showed that averagely was distinguished from other factors, and did not show about that. Above experiment values known that there was statically difference between Motion analysis and Ground reaction force under absorbing of the functional insole shoes which was not have an effect on our body for kinetics and kinematics.