• Title/Summary/Keyword: critical response

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Influence of exterior joint effect on the inter-story pounding interaction of structures

  • Favvata, Maria J.;Karayannis, Chris G.;Liolios, Asterios A.
    • Structural Engineering and Mechanics
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    • v.33 no.2
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    • pp.113-136
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    • 2009
  • The seismic induced interaction between multistory structures with unequal story heights (inter-story pounding) is studied taking into account the local response of the exterior beam-column joints. Although several parameters that influence the structural pounding have been studied sofar, the role of the joints local inelastic behaviour has not been yet investigated in the literature as key parameter for the pounding problem. Moreover, the influence of the infill panels as an additional parameter for the local damage effect of the joints on the inter-story pounding phenomenon is examined. Thirty six interaction cases between a multistory frame structure and an adjacent shorter and stiffer structure are studied for two different seismic excitations. The results are focused: (a) on the local response of the critical external column of the multistory structure that suffers the hit from the slab of the adjacent shorter structure, and (b) on the local response of the exterior beam-column joints of the multistory structure. Results of this investigation demonstrate that the possible local inelastic response of the exterior joints may be in some cases beneficial for the seismic behaviour of the critical column that suffers the impact. However, in all the examined cases the developing demands for deformation of the exterior joints are substantially increased and severe damages can be observed due to the pounding effect. The presence of the masonry infill panels has also been proved as an important parameter for the response of the exterior beam-column joints and thus for the safety of the building. Nevertheless, in all the examined inter-story pounding cases the presence of the infills was not enough for the total amelioration of the excessive demands for shear and ductility of the column that suffers the impact.

The aerostatic response and stability performance of a wind turbine tower-blade coupled system considering blade shutdown position

  • Ke, S.T.;Xu, L.;Ge, Y.J.
    • Wind and Structures
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    • v.25 no.6
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    • pp.507-535
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    • 2017
  • In the strong wind shutdown state, the blade position significantly affects the streaming behavior and stability performance of wind turbine towers. By selecting the 3M horizontal axis wind turbine independently developed by Nanjing University of Aeronautics and Astronautics as the research object, the CFD method was adopted to simulate the flow field of the tower-blade system at eight shutdown positions within a single rotation period of blades. The effectiveness of the simulation method was validated by comparing the simulation results with standard curves. In addition, the dynamic property, aerostatic response, buckling stability and ultimate bearing capacity of the wind turbine system at different shutdown positions were calculated by using the finite element method. On this basis, the influence regularity of blade shutdown position on the wind-induced response and stability performance of wind turbine systems was derived, with the most unfavorable working conditions of wind-induced buckling failure of this type of wind turbines concluded. The research results implied that within a rotation period of the wind turbine blade, when the blade completely overlaps the tower (Working condition 1), the aerodynamic performance of the system is the poorest while the aerostatic response is relatively small. Since the influence of the structure's geometrical nonlinearity on the system wind-induced response is small, the maximum displacement only has a discrepancy of 0.04. With the blade rotating clockwise, its wind-induced stability performance presents a variation tendency of first-increase-then-decrease. Under Working condition 3, the critical instability wind speed reaches its maximum value, while the critical instability wind speed under Working condition 6 is the smallest. At the same time, the coupling effect between tower and blade leads to a reverse effect which can significantly improve the ultimate bearing capacity of the system. With the reduction of the area of tower shielded by blades, this reverse effect becomes more obvious.

Impaired Response Inhibition in Patients with Obsessive-Compulsive Disorder (강박장애 환자의 반응억제 결함)

  • Boo, Young Jun;Kim, Se Joo;Kang, Jee In
    • Anxiety and mood
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    • v.11 no.1
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    • pp.33-37
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    • 2015
  • Objective : Impaired response inhibition has been suggested to play an important role in the pathophysiology of obsessive-compulsive disorder (OCD). The aim of this study was to evaluate the response inhibition in patients with OCD, by using the Go/NoGo paradigm, and to better understand its associations with clinical symptoms. Methods : The participants included 63 OCD patients and 80 healthy volunteers matched in age and sex. response inhibition was evaluated using computerized Go/NoGo task, in which their commission error rates, omission error rates, and mean response times were measured. The severity of clinical symptoms in the OCD patients was assessed using Montgomery-Asberg Depression Scale and Yale-Brown Obsessive Compulsive Scale. Result : OCD patients showed significantly impaired inhibition and higher omission errors rates despite their slower response time, compared to normal controls. Clinical symptoms were not correlated with commission errors and omission errors. Conclusion : The present results indicate that impairment in response inhibition may play a critical role in the pathophysiology of OCD as a trait. These findings suggest that deficit of response inhibition may contribute to developing and maintaining clinical symptoms such as compelling need to repeat certain actions in patients with OCD.

The Role of Inhaled Corticosteroid in the Management of Chronic Cough (만성 기침에서 스테로이드 흡입제의 역할)

  • Lee, Kyung-Hun;Jang, Seung Hun;Lee, Jung-Hwa;Eom, Kwang-Seok;Bahn, Joon-Woo;Kim, Dong-Gyu;Shin, Tae Rim;Park, Sang Myon;Lee, Myung-Gu;Kim, Chul-Hong;Hyun, In-Gyu;Jung, Ki-Suck
    • Tuberculosis and Respiratory Diseases
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    • v.60 no.2
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    • pp.221-227
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    • 2006
  • Background : Cough may be a consequence of bronchial hyperresponsiveness or inflammation. Empirical treatment is important in this context because it difficult to verify the obvious cause of cough using laboratory tests, Corticosteroid has a nonspecific anti-inflammatory effect, and can be used for cough management. However, its response rate has not yet been fully elucidated. This study investigated the short- term effects of inhaled corticosteroid on chronic cough Methods : Patients with chronic cough with a normal chest radiograph and a pulmonary function test were enrolled. Cases with a prior respiratory infection within 8 weeks, a history of bronchial asthma, objective wheezing on examination, subjective symptoms of gastroesophageal reflux or taking an ACE inhibitor were excluded. On the first visit, a methacholine bronchial provocation test, spontaneous sputum eosinophil count performed twice and a paranasal sinus radiograph were checked, and the patients were treated with budesonide turbuhaler $800{\mu}g/day$ for ten days. The primary outcome measure was a decrease in the cough score after treatment. Results : Sixty nine chronic coughers were finally analyzed. The final diagnoses by the routine tests were as follows: bronchial asthma 13.0%, eosinophilic bronchitis 18.8%, paranasal sinusitis 23.2% and non-diagnostic cases 53.6%. The following responses to the inhaled corticosteroid were observed: definite responders, 76.8%, possible responders, 2.9% and non-responders, 20.3%. The response rate was not affected by the final diagnosis even in the non-diagnostic cases. There were minimal adverse drug related effects during the empirical treatment. Conclusion : Routine objective tests such as methacholine provocation, sputum eosinophil count and simple radiographs were notare not suitable for diagnosing chronic cough Therefore, empirical treatment is important. Short term inhaled corticosteroid is effective and can guide a further treatment plan for chronic cough.

Clinical Application of Electromyography and Nerve Conduction Study (근전도와 신경전도 검사의 임상적 응용)

  • Kim Ho-Bong;Park Young-Han;Bae Sung-Soo
    • The Journal of Korean Physical Therapy
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    • v.10 no.1
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    • pp.199-212
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    • 1998
  • The purpose of this article is to summary about the application of electromyography and nerve conduction study. Electrodiagnostic studies, which include nerve conduction studies, electromyography, repetitive nerve stimulation, single fiber EMG, late response tests and evoked potential tests are a critical component of the neuromuscular evaluation.

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Clinical Application of Electromyography and Nerve Conduction Study (근전도와 신경전도 검사의 임상적 응용)

  • Kim, Ho-Bong;Bae, Sung-Soo
    • Journal of Korean Physical Therapy Science
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    • v.5 no.2
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    • pp.603-616
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    • 1998
  • The purpose of this article is to summary about the application of electromyography and nerve conduction study. Electrodiagnostic studies, which include nerve conduction studies, electromyography, repetitive nerve stimulation, single fiber EMG, late response tests and evoked potential tests are a critical component of the neuromuscular evaluation.

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A simulation system for distributed database design

  • Rho, Sangkyu
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1995.09a
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    • pp.46-58
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    • 1995
  • Although numerous distributed database design models and solution algorithms have been developed, very few have been validated. Validation is critical to the successful application of such models to distributed database design. In this paper, we develop a simulation system for distributed database design. We then analyze and validate an average response time model using simulation. The simulation results demonstrate that the average response time model is reasonably accurate.

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A Guideline for Motion-Image-Quality Improvement of LCD-TVs

  • Kurita, Taiichiro
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.1164-1167
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    • 2009
  • Motion-image-quality of LCD-TVs is discussed by dynamic spatial frequency response. Smaller temporal aperture or higher frame rate can improve dynamic response, but an increase of motion velocity easily cancels the improvement. A guideline for deciding the desirable temporal aperture and frame rate of LCD-TVs is described, under the condition that camera and display have the same parameters. Two candidates of the desirable parameter sets will be (240 or 300 Hz, 50 to 100% aperture) and (120Hz, 25 to 50% aperture), from the viewpoint of "limit of acceptance" on motion-imagequality-deterioration for critical picture materials.

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Analysis of Orthotropic Bearing Non-linearity Using Non-linear FRFs

  • Han Dong-Ju
    • Journal of Mechanical Science and Technology
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    • v.20 no.2
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    • pp.205-211
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    • 2006
  • Among other critical conditions in rotor systems the large non-linear vibration excited by bearing non-linearity causes the rotor failure. For reducing this catastrophic failure and predictive detection of this phenomenon the analysis of orthotropic bearing non-linearity in rotor system using higher order frequency response functions (HFRFs) is conducted and is shown to be theoretically feasible as that of non-rotating structures. The complex HFRFs based on the Volterra series are newly developed for the process and investigated their features by using the simple forms of the FRFs associated with the forward and the backward modes.

A Study on Mother's Verbal Response Types to Her Young Children (유아기 자녀에 대한 어머니의 언어반응 유형에 관한 연구)

  • Yoon, Hye-Jin
    • The Korean Journal of Community Living Science
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    • v.24 no.2
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    • pp.209-220
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    • 2013
  • This study is based on the interviews with six mothers to analyze their verbal response types with their young children ages 3-5 attending day-care center. This study was done from 10AM. to 12PM. August 18th 2012 at the director's room at P day care center in Seoul. For this study the following four situations mothers experience in child-rearing have been selected: self-achievement, sibling quarrel, nagging and isolation. As for the interview questionnaires the four verbal response types-stimulating, problem-solving, critical and indifferent ones-have been used. According to the results of this research, mothers tend to use stimulating verbal response types like praise in the situation of self-achievement; problem-solving response types like command in the situation of sibling quarrel; problem-solving response types like warning in the situation of nagging; and lastly, stimulating verbal response types like empathy in the situation of isolation. Mothers need to form more empathy with their children in such difficult situations as sibling quarrel or nagging. For mothers' efficient verbal responses for their children, accordingly, empathy in parent education needs to be more emphasized.