• Title/Summary/Keyword: passive state

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A Study on the Cognition Structure of Green Environment of Resident in the Multi-family Housing (공동주택단지 거주자의 자연지향과 녹환경 인식구조에 관한 연구)

  • 김준식;김익환
    • Journal of the Korean housing association
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    • v.15 no.2
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    • pp.87-96
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    • 2004
  • In this study, we analyzed the state of outdoor-space use and green-environment development for apartment residents, and investigated their ways of thinking on nature orientation and green environment. The results are as follows. 1) The ways of thinking and actual use of outdoor space by apartment residents appear different. 2) Due to the difference of apartment locations and complex environments, the state and reason of green environment construction are different between the residents of high-rise and low-storied apartments. 3) The residents of the low-storied apartments are more satisfied with the green environments of the complex than those of the high-rise apartments. In addition, constructing the green environment in a balcony and outdoor space enhances the satisfaction level of the apartment residents. 4) The residents of the low-storied apartments are passive in nature orientation, while those of the high-rise apartments are active. 5) Depending on the types of nature orientation, the apartment residents are grouped as 'people of nature experience', 'nature appreciators', or 'people of living-thing contact'. These groups show different patterns on the ways of thinking for outdoor space and green environment.

Numerical convergence and validation of the DIMP inverse particle transport model

  • Nelson, Noel;Azmy, Yousry
    • Nuclear Engineering and Technology
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    • v.49 no.6
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    • pp.1358-1367
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    • 2017
  • The data integration with modeled predictions (DIMP) model is a promising inverse radiation transport method for solving the special nuclear material (SNM) holdup problem. Unlike previous methods, DIMP is a completely passive nondestructive assay technique that requires no initial assumptions regarding the source distribution or active measurement time. DIMP predicts the most probable source location and distribution through Bayesian inference and quasi-Newtonian optimization of predicted detector responses (using the adjoint transport solution) with measured responses. DIMP performs well with forward hemispherical collimation and unshielded measurements, but several considerations are required when using narrow-view collimated detectors. DIMP converged well to the correct source distribution as the number of synthetic responses increased. DIMP also performed well for the first experimental validation exercise after applying a collimation factor, and sufficiently reducing the source search volume's extent to prevent the optimizer from getting stuck in local minima. DIMP's simple point detector response function (DRF) is being improved to address coplanar false positive/negative responses, and an angular DRF is being considered for integration with the next version of DIMP to account for highly collimated responses. Overall, DIMP shows promise for solving the SNM holdup inverse problem, especially once an improved optimization algorithm is implemented.

Research on the construction concept and general framework of Smart Water Resource

  • Tian, Yu;Li, JianGuo;Jiang, Yun-zhong
    • Proceedings of the Korea Water Resources Association Conference
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    • 2015.05a
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    • pp.216-216
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    • 2015
  • Frequent hydro-meteorological events caused by global climate change and human exacerbate activities, make the water resource problem more complicated. The increasing speed urbanization brings a significant impact on the city flood control and security, water supply safety, water ecological security, water environment safety and the water engineering security in China, and puts forward higher requirements to urban water integrated management, undoubtedly which become the biggest obstacle for water ecological civilization construction, thus urgent requiring an advanced methods to enhance the effectiveness of the water integrated management. The other fields of smart ideas point out a development path for water resource development. The construction demand of smart water resource is expounded in the paper, combining the philosophy of modern Internet of things with the application of cloud computing technology. The concept of smart water resource is analyzed, the connotation characteristics of smart water resource is extracted, and the general model of smart water resource is refined. Then, the frame structure of smart water resource is put forward. The connotation and the overall framework of the smart water resource represent a higher level of water resource informationization development and provide a comprehensive scientific and technological support to transform water resource management from an extensive, passive, static, branch and traditional management to a fine, active, dynamic, collaborative and modern management.

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Seismic performance-based optimal design approach for structures equipped with SATMDs

  • Mohebbi, Mohtasham;Bakhshinezhad, Sina
    • Earthquakes and Structures
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    • v.22 no.1
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    • pp.95-107
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    • 2022
  • This paper introduces a novel, rigorous, and efficient probabilistic methodology for the performance-based optimal design (PBOD) of semi-active tuned mass damper (SATMD) for seismically excited nonlinear structures. The proposed methodology is consistent with the modern performance-based earthquake engineering framework and aims to design reliable control systems. To this end, an optimization problem has been defined which considers the parameters of control systems as design variables and minimization of the probability of exceeding a targeted structural performance level during the lifetime as an objective function with a constraint on the failure probability of stroke length damage state associated with mass damper mechanism. The effectiveness of the proposed methodology is illustrated through a numerical example of performance analysis of an eight-story nonlinear shear building frame with hysteretic bilinear behavior. The SATMD with variable stiffness and damping have been designed separately with different mass ratios. Their performance has been compared with that of uncontrolled structure and the structure controlled with passive TMD in terms of probabilistic demand curves, response hazard curves, fragility curves, and exceedance probability of performance levels during the lifetime. Numerical results show the effectiveness, simplicity, and reliability of the proposed PBOD method in designing SATMD with variable stiffness and damping for the nonlinear frames where they have reduced the exceedance probability of the structure up to 49% and 44%, respectively.

MCS/IEI and Personal Exposures of VOCs in Office Worker (사무직 종사자가 일상생활에서 노출되는 VOCs 농도와 화학물질과민증 자각증상에 관한 연구)

  • Choi, Yoo-Rim;Sung, Ki-Chul;Chun, Chung-Yoon;Park, Jun-Seok
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2006.11a
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    • pp.322-327
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    • 2006
  • In our previous research, office workers are relatively frequent in self-reported symptoms suggestive of MCS/IEI compare to construction worker who highly exposed to VOCs compounds. However in that research, the subjects were too small to say it clearly. Based on that research results, self reported symptom surveys to 110 office workers and personal exposure concentration measurement were conducted to 13 of people. VOCs exposure levels were measured within office, house and other places during a week by Passive Sampling Method. In this study, it was found that the number of office workers who met the operational criteria of MCS/IEI was 23.6% similar to 24.5% of previous result, and average of TVOC concentration was appeared high state by order of office, house, and personal exposure.

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A study on the management-maintenance system in urban park (도시공원의 관리체계에 관한 연구)

  • 김동필;이기철
    • Journal of the Korean Institute of Landscape Architecture
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    • v.23 no.4
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    • pp.1-11
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    • 1996
  • The purpose of this study was to suggest the more efficient system for management in urban park through the investigation of the managemental condition. Research sites for managemental condition were 9 municipal park managemental offices in Seoul, Pusan and Taegu. The degree of the managemental state in these parks was generally passive and low. So, each of them had to consider the ways how to buy private-owned sites, to standardize facility maintenance, to characterize the managemental objects, to enlarge managemental personnels and systems, to apply entrusting management, to plan user-service strategies and to shorten expenditures. Particularly the positive managemental improvement in user control was demanded to cope with the changing social needs. In long term, they had to develop basic elements for the reasonable park management, clear park maps, area of facilities, the event, citizen participation, budgets and etc., and had to prepare the middle-long term management plan and the precise analysis to the managemental criteria.

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Output Feedback Passivation of Non-square Linear Systems Using an Input-Dimensional Compensator (입력 차수 보상기를 이용한 비정방 선형 시스템의 출력 궤환 수동화)

  • 손영익
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.53 no.1
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    • pp.10-15
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    • 2004
  • We present a state-space approach to make non-square linear systems strictly passive by using an input-dimensional parallel feedforward compensator. A necessary and sufficient condition for the existence of the parallel feedforward compensator is given by the static output feedback formulation, which enables to utilize linear matrix inequality. By modifying the structure of the compensator the additional technical assumption in the previous result [1] is removed. The effectiveness of the proposed method is illustrated by some numerical examples which can be stabilized by the proportional-derivative (PD) and proportional-derivative-integral (PID) control laws. The proposed control scheme can successfully replace the measurements of derivative terms in the control laws.

Implementation of Vector control for induction motor using the AC-AC matrix converter (교류-교류 행렬변환기를 이용한 유도전동기의 벡터제어 구현)

  • Kim, Woo-Hyun
    • Journal of the Korean Society of Industry Convergence
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    • v.6 no.1
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    • pp.3-10
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    • 2003
  • Application of matrix converter to vector control of induction motor using simplified Venturini algorithm which is capable of achieving the maximum output voltage is developed. This algorithm simplifies the control algorithm and therefor reduces the digital implementation time. Matrix converter is used as voltage-referenced voltage fed vector controlled induction motor drive. This paper describes the performance of vector controlled induction motor with four quadrant capability employing a matrix converter power circuit. The advantage of this system over the conventional rectifier-inverter arrangement are capability for regeneration into the utility, sinusoidal supply currents and minimum passive components. The steady-state and transient performance of the induction motor drive under the vector control technique is demonstrate with simulation and experiment results.

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Design of an Intelligent Tutoring System based on Web Learning Assessment (웹 학습 평가에 기반한 지능형 교수 시스템의 설계)

  • 최숙영
    • Journal of Korea Society of Industrial Information Systems
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    • v.6 no.3
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    • pp.71-78
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    • 2001
  • Since web-based tutoring systems are generally composed with passive and static hypertext, they could not provide adaptive learning environments according to learning ability of each student. In this study, we suggest an intelligent tutoring system, which grasps the learning state of student and provides each student with dynamic learning materials suitable to individual feature based on learning result. It is an agent based system, in which, courseware knowledge for learning is effectively constructed, the proper feedback according to learning assessment is inferred, and it is given to each student.

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The MPI CyberMotion Simulator: A Novel Research Platform to Investigate Human Control Behavior

  • Nieuwenhuizen, Frank M.;Bulthoff, Heinrich H.
    • Journal of Computing Science and Engineering
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    • v.7 no.2
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    • pp.122-131
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    • 2013
  • The MPI CyberMotion Simulator provides a unique motion platform, as it features an anthropomorphic robot with a large workspace, combined with an actuated cabin and a linear track for lateral movement. This paper introduces the simulator as a tool for studying human perception, and compares its characteristics to conventional Stewart platforms. Furthermore, an experimental evaluation is presented in which multimodal human control behavior is studied by identifying the visual and vestibular responses of participants in a roll-lateral helicopter hover task. The results show that the simulator motion allows participants to increase tracking performance by changing their control strategy, shifting from reliance on visual error perception to reliance on simulator motion cues. The MPI CyberMotion Simulator has proven to be a state-of-the-art motion simulator for psychophysical research to study humans with various experimental paradigms, ranging from passive perception experiments to active control tasks, such as driving a car or flying a helicopter.