• 한국안전학회지
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• 제13권4호
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• pp.59-70
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• 1998

In this study, response time index(RTI) of standard and quick response type sprinkler head are measured and compared through ramp and plunge test in heated wind tunnel. Also discharge rate and water distribution, actual delivered density(ADD), fire test with wood cribs are performed to compare the fire suppression capability and the operation time and temperature between standard and quick response type sprinkler head.

• Earthquakes and Structures
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• 제18권2호
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• pp.263-273
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• 2020

The use of energy concepts in seismic analysis and design of structures requires the understanding of the input energy response of multi-degree-of-freedom (MDOF) systems subjected to strong ground motions. For design purposes and non-time consuming analysis, however, it would be beneficial to associate the input energy response of MDOF systems with those of single-degree-of-freedom (SDOF) systems. In this paper, the theoretical formulation of energy input to MDOF systems is developed on the basis that only a particular portion of the total mass distributed among floor levels is effective in the nth-mode response. The input energy response histories of several reinforced concrete frames subjected to a set of eleven horizontal acceleration histories selected from actual recorded events and scaled in time domain are obtained. The contribution of the fundamental mode to the total input energy response of MDOF frames is demonstrated both graphically and numerically. The input energy of the fundamental mode is found to be a good indicator of the total energy input to two-dimensional regular MDOF structures. The numerical results computed by the proposed formulation are verified with relative input energy time histories directly computed from linear time history analysis. Finally, the elastic input energies are compared with those computed from time history analysis of nonlinear MDOF systems.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.945-951
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• 2022

The major objective of this research is to evaluate performance of improved intersections for response time to emergency vehicle preemption. Smart technologies have been introduced to civil infrastructure systems for resilient communities. The technologies need to evaluate their effectiveness and feasibility to confirm their introduction. This research focuses on the performance of emergency vehicle preemption, represented by response time, when smart intersections are introduced in a community. The response time is determined by not only intersections but also a number of factors such as traffic, distance, road conditions, and incident types. However, the evaluation of emergency response has often ignored factors related to emergency vehicle routes. In this respect, this research synthetically analyzes geospatial and incident data using each route of emergency vehicle and conducts before-and-after evaluations. The changes in performance are analyzed by the impact of smart intersections on response time through Bayesian regression models. The result provides measures of the project's performance. This study will contribute to the body of knowledge on modeling the impacts of technology application and integrating heterogeneous data sets. It will provide a way to confirm and prove the effectiveness of introducing smart technologies to our communities.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1999년도 봄 학술발표회 논문집
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• pp.159-168
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• 1999

In seismic analysis, there are two main ways - uniform load method and dynamic analysis, dynamic analysis can be divided into response spectrum analysis and time history analysis. In case of which get the complexion of the vibration with 3-axis of coordinate direction in each mode of free vibration mode happened owing to complication of the shape, 3-dimensional dynamic analysis is recommended to perform as multi-mode spectral analysis in standard specification for highway bridge. The purpose of this study is to understand the dynamic behavior by performing multi-mode seismic analysis according to responses analysis and time history anal)'sis in using record of earthquake. In accordance with the criterion of seismic design as defined in standard specification for highway bridge by using modified records of the El Centre and Coyote Lake earthquake, response spectrum was constructed by using the tripartite logarithmic plot. The 3-span continuous space truss bridge was selected as model of numerical analysis. As the result performed time history analysis and analysis of response spectrum for the model of numerical analysis, the result of time history analysis was slightly larger than that of response spectrum analysis. This coincide with the tendency of the result came from the analysis when using a jagged response spectrum analysis, This coincide with the tendency of the result came from the analysis when using a jagged response spectrum for a single excitation. In the Process of performing these two analysis. response spectrum analysis is more effective than time history analysis in saving times in analyzing data.

• 한국군사과학기술학회지
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• 제8권3호
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• pp.73-82
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• 2005

This paper describes shock waveform synthesis methods for a shock response spectnlm over a short time interval with which intereference between parts within a test item is increased to perform a sufficient shock test for damage or malfunction which may be caused by the interference between parts, and a digital filter for obtaining a shock response history required for the shock waveform synthesis and a digital inverse filter for restoration by inversely using the digital filter. The time at which the maximax value occurs in the response history is detected in order to establish a delay time which is one of the parameters in the wavelet, on the condition that the natural frequency of SDOF system with a Q (quality factor) of 10 equals to the wavelet frequency of the zero delay wavelet input. A shock response spectrum over a short time interval and an abrupt change in the acceleration for an instant are illustrated as features of the synthesized waveform.

• 패션비즈니스
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• 제4권3호
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• pp.103-114
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• 2000

The purpose of this study was to test the discriminant analysis model of Quick Response system and to examine the detailed relationship between each discriminant factor and Quick Response adoption. In this discriminant analysis model of Quick Response system, firm size, strategic type, product category, fashion trend, selling time and the Quick Response benefits were included as discriminant factors. Onehundred and two subjects were randomly selected for the survey study and discriminant analysis, descriptive analysis, t-test, and x square test were used for the data analysis. The results of this study were: 1. Wilks Lambda and F value support the discriminant analysis model that, taken together firm size, strategic type, product category, fashion trend, selling time and the Quick Response benefits significantly help to explain Quick Response adoption. 2. The importance of discriminant ability was, in order, firm size, the Quick Response benefits, women's wear, fashion trend, analyzer, selling time, reactor, defender and men's wear. 3. The discriminant function had the high hit ratio, so this can be well used for the classification of Quick Response adoption/nonadoption.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1998년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Spring 1998
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• pp.12-19
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• 1998

Response spectrum analysis method is widely used for seismic analysis of building structure. Analysis of structural vibration for equipment, machine and moving loads are executed by time history analysis. This method is very complex, difficult and tedious. In this study, maximum response of structure for this case are simply and fast. calculated by mode shape and response spectrum for excitation. At first, Response spectrum and time history analysis for some earthquake is carried and investigate the error of maximum displacement response for R. S. A. Secondly, The process for response spectrum analysis in excitation are calculated, and maximum model response are combined by CQC (Complete Quadratic Combination) methods. Finally, Combining maximum displacement response is compared with one of time history analysis.

• 대한기계학회논문집B
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• 제33권6호
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• pp.411-417
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• 2009

The transient shear stress response of an electrorheological fluid is investigated experimentally. The characteristic time constants of an electrorheological fluid sheared between two concentric cylinders were obtained under various electric field strengths and shear rates. Also, two experimental modes are adopted to investigate the effect of the shear flow on the dynamic behavior of the fluid; one is that the electric field is induced before shearing, and the other is the electric field is induced after shearing. From the difference in the response time between two modes, the cluster formation time were obtained. The response times were decreased with the increase of the shear rate, irrelatively of the electric field strength. The cluster formation time were monotonically increased with increase of shear rate, and thereafter, were converged with a certain value.

• 전자공학회논문지
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• 제50권9호
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• pp.179-185
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• 2013

본 논문에서는 시각에 대해 반응하는 운동 행동의 효과를 분석하기 위해서 응답속도정합-유발전위(RTA-ERP: Response Time Aligned-Event Related Potential)를 모델링하고, RTA-ERP의 진폭과 응답 속도를 이용하여 사이먼 효과를 분석하였다. 건강한 성인 15명(남성 9명, 여성 6명, 평균 연령 31세)을 대상으로, 같은 숫자에 대한 다른 숫자를 찾아 반응하는 '양자극방안' 실험을 7분 동안 수행하였다. 실험결과 제안된 RTA-ERP는 기존의 ERP에 비해 뇌에서의 처리시간 차이에 따른 변이를 보상할 수 있었으며, 향상된 LRP(Lateralized Readiness Potential)와 Pe(Error Related Positivity)를 나타내었다. '일치', '불일치' 시험 패턴에 대하여 '일치'에 대한 RTA-ERP의 진폭과 응답속도는 각각 '불일치'보다 컸으며 진폭은 $0.03{\mu}V$ 크고 반응속도는 43 ms 만큼 빨랐다. 응답속도에 따른 동기 시점을 보정하여 정합함에 따라, RTA-ERP의 진폭특성은 사이먼 효과의 특징인 ERP의 P300 진폭과 대응함을 확인하였다.

• 정보처리학회논문지C
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• 제15C권4호
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• pp.321-328
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• 2008

본 논문에서는, 혼잡 망에서의 큐 제어 방식과 전송 지연 시간에 대한 웹 반응 시간을 분석하였다. FIFO 방식에서는, 웹 반응 시간이 큐 크기에 대해서 거의 일정한 성능을 보여주었으나, 트래픽 부하가 높아질수록 웹 반응 시간은 길어졌다. 80%의 트래픽 부하보다, 90%와 98%의 트래픽 부하일 경우에, 큐 크기가 달라짐에 따라 웹 반응 시간이 더 뚜렷하게 다르게 나타났다. 특히 전송 지연 시간이 짧을 경우, 웹 반응 시간의 차이가 더욱 뚜렷하게 나타났다. RED 방식에서는, 상대적으로 큰 큐 크기일 경우, 3가지 서로 다른 설정의 RED 방식이 웹 반응 시간에 뚜렷한 영향을 미치지 못하였다. 큐 크기가 작아졌을 경우, 짧은 전송 지연에 대하여 각 RED 방식의 웹 반응 시간이 서로 뚜렷하게 다르게 나타났다. FIFO와 RED의 비교에서, 긴 전송 지연 시간일 경우, RED 방식이 FIFO보다 작은 웹 반응 시간을 보여주었다.