• 제목/요약/키워드: function of recovery

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크리프 회복 거동을 고려한 철근콘크리트 및 프리스트레스트 콘크리트 부재의 장기거동해석에 관한 연구 (Time-dependent Analysis of Reinforced and Prestressed Concrete Structures Incorporating Creep Recovery Function)

  • 김세훈;오병환
    • 콘크리트학회지
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    • 제11권1호
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    • pp.279-288
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    • 1999
  • 콘크리트 구조물의 크리프해석은 주로 크리프식의 중첩원리에 기초한 방법에 의해 수행되고 있다. 그러나 크리프식의 중첩을 응력이 증가하거나 일정할 경우에는 비교적 정확한 예측이 가능하지만, 응력이 감소하는 경우에는 상당한 오차를 나타낸다. 이것은 지속하중과 응력감소 과정에서 크리프와 관련된 콘크리트의 성질이 변화되므로 크리프 회복을 크리프 식의 중첩으로 정확하게 모사할수 없기 때문이다. 따라서, 본 연구에서는 감소와 증가를 반복하는 응력 이력을 지니는 콘크리트 구조물의 좀더 정확하고 합리적인 장기거동 해석을 위하여 응력의 감소를 단순히 크리프식의 중첩에 의해 해석한 기존의 방법과는 달리 크리프식과 크리프 회복식으로 표현하여, 소위 2함수 방법(two-function method)를 콘크리트구조물의 해석에 적용하는 방법을 제시하였다. 본 연구의 2함수방법을 콘크리트 구조물의 장기거동 해석을 적용하기 위해, 시간단계 동안 다양한 응력 변화에 대하여 크리프 변형도 증분량을 계산하는 방법을 제시하였다. 본 연구의 해석방법에 의해서 해석된 결과를 기존의 크리프식의 중첩에 의한 결과 및 기존의 실험결과들과 비교 분석한 결과, 기존의 중첩법은 실험결과와 많은 차이를 보이고 있으나 본 연구의 해석방법은 실험결과와 잘 맞고 있음을 보여주고 있다. 따라서, 크리프회복식을 이용하는 본 연구의 해석방법은 기존의 크리프식의 중첩방법이나 기존의 설계기준에 비해 변화하는 응력이력 하에서의 콘크리트 구조물의 크리프거동을 더 정확하게 서술할 수 있는 방법으로서 앞으로 설계기준 작성과 실제 구조물 해석에 효율적인 응용이 기대되고 있다.

New Treatment in Facial Nerve Palsy Caused by Sagittal Split Ramus Osteotomy of Mandible

  • Lee, Jin Hoon;Lee, Kyung Ah
    • 대한두개안면성형외과학회지
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    • 제18권1호
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    • pp.65-70
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    • 2017
  • A 25-years-old woman with mandibular prognathism underwent a mandibular setback by way of mandibular sagittal split ramus osteotomy (MSSRO). After 2 days of operation, she developed difficulty of closing her right eye. The blink reflex test and motor nerve conduction study of the right orbicularis oris muscle were revealed right facial neuropathy of unknown origin and House-Brackmann facial nerve grading system (HBFNGS) grade V. For treatment, we initially prescribed oral prednisolone and nimodipine including physical therapy. The samples consisted of 11 facial nerve palsy patients caused by MSSRO and were analysed about onset of facial nerve palsy, postoperative HBFNGS, final HBFNGS, treatment method and recovery time. At 10 weeks of treatment of nimodipine, she had completely regained normal function (HBFNGS grade I) of the right facial nerve. The clinical results lead to assume a fast recovery of facial nerve function by the nimodipine medication, whereas average time of recovery is 16.32 weeks in references. Despite of the limited one patient treated, the result was very promising with respect to a faster recovery of the facial nerve function. Considering the use of nimodipine treatment for peripheral facial nerve palsy following a surgical approach with an anatomically preserved nerve can be recommended.

적출 쥐 심장에서 허혈성 전조건화가 심정지후 좌심실 기능에 미치는 영향 (Effect of ischemic preconditioning on left ventricular function after cardiac arrest in isoated rat heart)

  • 조대윤
    • Journal of Chest Surgery
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    • 제27권7호
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    • pp.563-570
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    • 1994
  • Effect of ischemic preconditioning on left ventricular function after cardiac arrest in isolated rat heart.Ischemic preconditioning reduces infarct size caused by sustained ischemia. However, the effects of preconditioning on post ischemic cardiac function are not well-known. The objective of the present study was to determine whether preconditioning would improve the recovery of left ventricular functions after cardiac arrest in isolated rat heart model.Isolated rat hearts were allowed to equilibrate for 20 minutes and were then subjected to either 5 minutes of global, normothermic transient ischemia [Group 2 and 4] or not [Group 3]. A stabilization period of perfusion lasting 5 minutes after the termination of transient ischemia was followed by a standard global, normothermic 20 minute-ischemia and 35-minute reperfusion challenge [Group 3 and 4]. These following results were odtained.1. The recovery of left ventricular developed pressures showed no significant differences between Group 3 and Group 4 at 50 [P>0.3] and 85 minute [P>0.2].2. Heart rates showed no significant differences throughout all the course of experiment and between groups [P>0.5].3. The recovery of left ventricular maximum dP/dt showed no significant differences between Group 3 and Group 4 at 50 [P>0.1] and 85 minute [P>0.2].4. The recovery of pressure-rate products showed no significant differences between Group3 and Group 4 at 50 [P>0.5] and 85 minute [P>0.1].These results suggest that ischemic preconditioning does not provide significant benefit for the postischemic left ventricular functions in isolated rat hearts.

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A Comparative Study on Recovery of Motor Function in Stroke Patients with Corona Radiata Infarcts and Intracerebral Hemorrhage

  • Kim, Chung-Sun;Park, Sang-Young;Kwon, Jung-Won
    • The Journal of Korean Physical Therapy
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    • 제22권6호
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    • pp.53-58
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    • 2010
  • Purpose: Our goal was to determine the difference in motor recovery between two stroke types: the corona radiata (CR) infarct type and the intracerebral hemorrhage (ICH) type, by using assessment methods for motor functions. Methods: Forty subjects who were diagnosed as having had a stroke with an infarct (men: 11, women: 9, mean age: $62.25{\pm}7.59$) or a stroke with an ICH (men: 12, women: 8, mean age: $59.75{\pm}6.11$) were recruited. In all subjects, motor functions of the affected extremities were measured 2 times: at stroke onset (initial) and 6 months after the onset (final) by the motricity index (MI), the modified Brunnstrom classification (MBC), and functional ambulatory category (FAC). We compared the final assessment with the initial one. Results: Motor functions of all patients improved with the passing of time. All scores of motor function assessment in the ICH type were higher than in the infarct type. Comparing the initial assessment with the final one, upper MI and MBC scores of the upper extremities were significantly different between the two stroke types (p<0.05), but lower MI and FAC scores of the lower extremities were not (p>0.05). Conclusion: These findings imply that patterns of motor recovery in patients with either the infarct type or the ICH type of stroke change for the better over time. The degree of motor recovery in the ICH type was better than in the infarct type. Therefore, one can introduce clinical interventions by the aspect of progress in functional motor recovery.

전기체 낙하산 시스템의 장착에 대한 인증 고려사항 (Consideration on certification of installation of whole airplane recovery parachute)

  • 김성겸
    • 항공우주시스템공학회지
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    • 제10권2호
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    • pp.22-26
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    • 2016
  • Whole airplane recovery parachute system(WARPS) is a auxiliary safety system to protect occupants in emergency situation where recovery to normal flight condition is impossible. In this paper, application and certification cases of WARPS for Part 23 small airplane is introduced and considerations in certification of the WARPS installed airplane are provided in terms of performance of parachute, function and operation, loads and strength and protection of occupants.

소풍탕이 허혈성 뇌손상 흰쥐의 인지 및 운동기능회복에 미치는 효과 (Neuroprotective Effects of Sopung-tang(Shufeng-tang) on Cognition and Motor Function Recovery after Ischemic Brain Injury in Rats)

  • 추민규;최진봉;신미숙;김선종
    • 한방재활의학과학회지
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    • 제18권2호
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    • pp.45-60
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    • 2008
  • Objectives : Sopung-tang(Shufeng-tang) is a famous herbal prescription that treated ischemic brain injury. This study was designed to evaluate the effects of Sopung-tang(Shufeng-tang) on congnition and motor function recovery after ischemic brain injury in rats. Methods : Male rats were divided into 4 groups. Those rats caused ischemic brain injury by occlusion of MCA as Longa method. Control group I was per os normal saline for 7 days after ischemic brain injury. Control group II was per os normal saline for 14 days after ischemic brain injury. Experimental group I(Ex I) was taken with Sopung-tang(Shufeng-tang) for 7 days after ischemic brain injury. Experimental group II(Ex II) was taken with Sopung-tang(Shufeng-tang) for 14 days after ischemic brain injury. The author carried out neurological, cognitive motor behavior tests and histological assessment. Neurological motor behavior tests consist of limb placement test, beam-walking test and horizontal wire test. Morris water maze test was used for cognitive motor behavior test. In the histological assessment test, TTC(2,3,5-triphenylteterazolium chloride) staining, Hematoxylin & Eosin staining and immunohistochemical staining were experimented. Results : 1. In neurological motor behavior tests, motor function recovery was significantly increased in the experimental groups as compared with control groups(p<0.05). Especially Ex II was significantly increased as compared with Ex I(p<0.05). 2. In Morris water maze test, congnitive motor function recovery was significantly increased in the experimental groups as compared with control group(p<0.05). Especially Ex II was significantly increased as compared with Ex I(p<0.05). 3. In the immunohistochemical staining for the expression of BDNF in hippocampus, more immune reaction was investigated in the experimental groups as compared with control groups. Especially most immune reaction was experimented in the EX II. Conclusions : According to the above results, Sopung-tang(Shufeng-tang) can treat on the congnition and motor function recovery after ischemic brain injury in rats. And it is effective method in expression of BDNF in hippocampus.

세포의 자가 치료 기능을 모사한 디지털 회로에서의 오류위치 확인 및 복구 알고리즘 (An recovery algorithm and error position detection in digital circuit mimicking by self-repair on Cell)

  • 김석환;허창우
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2015년도 추계학술대회
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    • pp.842-846
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    • 2015
  • 본 연구에서는 세포의 자가 치료 기능을 모사하여 복잡한 디지털 회로를 기능별 분리시킨 구조에서 회로 동작 중 발생하는 오류 위치를 빠르게 찾고 복구 시키는 알고리즘 방법을 제안한다. 디지털 회로를 각 기능별로 9가지로 분리시켜 오류 난 디지털 회로의 기능블록 위치를 빠르게 검출할 수 있게 하며 복구 시키는 방법을 제안한다. 복잡한 구조의 디지털 회로에서도 각 디지털 회로의 기능 별 위치에 대한 번호 및 좌표를 $3{\times}3$ 행렬 구조로 확대시켜 오류 위치에 대아여 검출 및 복구가 가능한 알고리즘이다.

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세포의 자가 치료 기능을 모사한 디지털 회로에서의 오류 검출 및 복구 알고리즘 (An Error Detection and Recovery Algorithm in Digital Circuit Mimicking by Self-Repair on Cell)

  • 김석환
    • 한국정보통신학회논문지
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    • 제19권11호
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    • pp.2745-2750
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    • 2015
  • 본 연구에서는 세포의 자가 치료 기능을 모사하여 복잡한 디지털 회로를 기능별 분리시킨 구조에서 회로 동작 중 발생하는 오류 위치를 빠르게 찾고 복구 시키는 알고리즘 방법을 제안한다. 디지털 회로를 각 기능별로 9가지로 분리시켜 오류 난 디지털 회로의 기능블록 위치를 빠르게 검출할 수 있게 하며 복구 시키는 방법을 제안한다. 복잡한 구조의 디지털 회로에서도 각 디지털 회로의 기능별 위치에 대한 번호 및 좌표를 $3{\times}3$ 행렬 구조로 확대시켜 오류 위치에 대하여 검출 및 복구가 가능한 알고리즘이다.

트리검색 기법을 이용한 희소신호 복원기법 (Sparse Signal Recovery Using A Tree Search)

  • 이재석;심병효
    • 한국통신학회논문지
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    • 제39A권12호
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    • pp.756-763
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    • 2014
  • 본 논문에서는 트리검색 기반의 GTMP (matching pursuit with greedy tree search)이라는 새로운 희소신호 복원기법을 제안한다. 트리검색은 비용함수 (cost function)를 최소화함으로써 희소신호 복원 성능을 향상시키기 위해 적용하였다. 또한 각 노드마다 트리제거 (tree pruning)기법을 이용하여 효율적인 알고리듬을 개발하였다. 본 논문에서는 알고리듬의 성능분석을 통해 희소신호에서 영(0)이 아닌 값의 위치를 정확히 찾아내는 조건을 도출하였다. 그리고 실험을 통해 GTMP가 기존의 희소신호 복원기법에 비해 성능이 향상되었음을 보였다.

Hydrothermal liquefaction of Chlorella vulgaris: Effect of reaction temperature and time on energy recovery and nutrient recovery

  • Yang, Ji-Hyun;Shin, Hee-Yong;Ryu, Young-Jin;Lee, Choul-Gyun
    • Journal of Industrial and Engineering Chemistry
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    • 제68권
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    • pp.267-273
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    • 2018
  • Hydrothermal liquefaction of Chlorella vulgaris feedstock containing 80% (w/w) water was conducted in a batch reactor as a function of temperature (300, 325 and $350^{\circ}C$) and reaction times (5, 10 and 30 min). The biocrude yield, elemental composition and higher heating value obtained for various reaction conditions helped to predict the optimum conditions for maximizing energy recovery. To optimize the recovery of inorganic nutrients, we further investigated the effect of reaction conditions on the ammonium ($NH_4{^+}$), phosphate ($PO_4{^{3-}}$), nitrate ($NO_3{^-}$) and nitrite ($NO_2{^-}$) concentrations in the aqueous phase. A maximum energy recovery of 78% was obtained at $350^{\circ}C$ and 5 min, with a high energy density of 34.3 MJ/kg and lower contents of oxygen. For the recovery of inorganic nutrients, shorter reaction times achieved higher phosphorus recovery, with maximum recovery being 53% at $350^{\circ}C$ and 5 min. Our results indicate that the reaction condition of $350^{\circ}C$ for 5 min was optimal for maximizing energy recovery with improved quality, at the same time achieving a high phosphorus recovery.