• Title/Summary/Keyword: isolation techniques

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A Development of Vibration Isolation Technology for a Large Structure using Experimental Research (실험적 기법을 이용한 대형구조물 교통진동 차진기술 개발)

  • Ryu, B.J.;Lee, H.G.;Son, S.W.;Lee, G.S.;Han, H.H.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2006.11a
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    • pp.537-542
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    • 2006
  • This paper deals with the vibration isolation techniques for a large structure using experimental research. In the case of vibration isolation for the vicinity of a subway or a railroad station, most of vibration isolation techniques using isolation materials with high isolation efficiency only, have been applied. Therefore, the quantitative evaluation and design technologies are required for a vibration isolation of large structures. In this study, firstly, vibration characteristics due to train or subway are analyzed. Secondly, the performance of existing vibration isolation materials such as precision isolation material, elastomer is estimated through the experiments. Thirdly the performance of tire isolation material and its frame is tested and evaluated.

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INTEGRATION OF CONSTRUCTION TECHNIQUES FOR SPECIAL ISOLATION WARDS OF HOSPITAL BUILDINGS

  • Chi-Su Tai ;Sy-Jye Guo
    • International conference on construction engineering and project management
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    • 2005.10a
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    • pp.627-632
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    • 2005
  • The severe acute respiratory syndrome -SARS virus spreaded rapidly in Asia in 2003 caused a lethal and serious epidemic. Establishing special isolation wards of high-level epidemic prevention has becomes one of the most important tasks of epidemic prevention. Taking the biosafety level of US CDC biology laboratory as an example, the laboratory of the highest level, BL4 and that of the second high level, BL3 are only allowed to handle and research this kind of highly dangerous viruses safely, to ensure the safety of researchers and the surrounding environment.This research aims to study the functions and the design requirements of "special isolation wards", which is equivalent to the high-level biotechnology laboratory, and have an integrated discussion about the design and construction techniques of this kind of wards, expecting to provide a reference for constructing special isolation wards and maintaining operation safely in Taiwan.

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Semi-active storey isolation system employing MRE isolator with parameter identification based on NSGA-II with DCD

  • Gu, Xiaoyu;Yu, Yang;Li, Jianchun;Li, Yancheng;Alamdari, Mehrisadat Makki
    • Earthquakes and Structures
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    • v.11 no.6
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    • pp.1101-1121
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    • 2016
  • Base isolation, one of the popular seismic protection approaches proven to be effective in practical applications, has been widely applied worldwide during the past few decades. As the techniques mature, it has been recognised that, the biggest issue faced in base isolation technique is the challenge of great base displacement demand, which leads to the potential of overturning of the structure, instability and permanent damage of the isolators. Meanwhile, drain, ventilation and regular maintenance at the base isolation level are quite difficult and rather time- and fund- consuming, especially in the highly populated areas. To address these challenges, a number of efforts have been dedicated to propose new isolation systems, including segmental building, additional storey isolation (ASI) and mid-storey isolation system, etc. However, such techniques have their own flaws, among which whipping effect is the most obvious one. Moreover, due to their inherent passive nature, all these techniques, including traditional base isolation system, show incapability to cope with the unpredictable and diverse nature of earthquakes. The solution for the aforementioned challenge is to develop an innovative vibration isolation system to realise variable structural stiffness to maximise the adaptability and controllability of the system. Recently, advances on the development of an adaptive magneto-rheological elastomer (MRE) vibration isolator has enlightened the development of adaptive base isolation systems due to its ability to alter stiffness by changing applied electrical current. In this study, an innovative semi-active storey isolation system inserting such novel MRE isolators between each floor is proposed. The stiffness of each level in the proposed isolation system can thus be changed according to characteristics of the MRE isolators. Non-dominated sorting genetic algorithm type II (NSGA-II) with dynamic crowding distance (DCD) is utilised for the optimisation of the parameters at isolation level in the system. Extensive comparative simulation studies have been conducted using 5-storey benchmark model to evaluate the performance of the proposed isolation system under different earthquake excitations. Simulation results compare the seismic responses of bare building, building with passive controlled MRE base isolation system, building with passive-controlled MRE storey isolation system and building with optimised storey isolation system.

Isolation of Microorganisms for Biotechnological Application

  • Franco, Christopher-M.M.;Mcclure, Nicholas-C.
    • Journal of Microbiology and Biotechnology
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    • v.8 no.2
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    • pp.101-110
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    • 1998
  • The extent of biological diversity being revealed by molecular techniques accentuates the need to develop methods to isolate and culture the large numbers of microorganisms that remain to be studied. The discovery and characterization of novel microorganisms will provide information useful in understanding microbial ecosystems and have the potential to lead to new products for the biotechnology industry. In this review, the use of innovative techniques and exploration of unusual ecosystems, that have begun to address the challenge of isolating the "uncultured" members of the microbial population, are examined.

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Experimental Study on Railway Vibration Isolation of a Large Structure using Isolation Materials (방진재를 이용한 대형구조물의 철도 진동에 관한 실험적 연구)

  • Ryu, Bong-Jo;Lee, Hong-Gi;Koo, Kyung-Wan
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.6
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    • pp.1286-1292
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    • 2011
  • The paper deals with the vibration isolation of a large structure using an experimental technology. In the case of vibration isolation for the vicinity of a subway or a railroad station, most of vibration isolation techniques using isolation materials with high isolation efficiency only, have been applied. Therefore, the quantitative evaluation and design technologies are required for a vibration isolation of large structures. In this study, firstly, vibration characteristics due to train or subway are analyzed. Secondly, the performance of existing vibration isolation materials such as precision isolation material, elastomer is estimated through the experiments. Thirdly, the performance of a tire isolation material and its frame is tested and evaluated. Finally, it is shown that tire isolation materials can be applied to the vibration isolation or vibration reduction of large structures.

Design of Observer-Based Fault Detection and Isolation techniques for Induction Motors (유도전동기를 위한 관측기 기반의 고장 감지 및 분리 기법 설계)

  • Han, Byung-Jo;Park, Gi-Kwang;Koo, Kyung-Wan;Yang, Hai-Won
    • Proceedings of the KIEE Conference
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    • 2009.04a
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    • pp.77-79
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    • 2009
  • Nonlinear system fault detection and isolation of this paper is about the failure of unknown function approximation using neural network for fault detection and isolation techniques of induction motors were applied. observer-based fault signal residual value was used. Induction motor using the speed controller of the backstepping controller. Proposed fault detection and isolation to prove the performance of the simulation was applied to and the actual system.

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Hybrid Fault Detection and Isolation Techniques for Aircraft Inertial Measurement Sensors

  • Kim, Seung-Keun;Jung, In-Sung;Kim, You-Dan
    • International Journal of Aeronautical and Space Sciences
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    • v.7 no.1
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    • pp.73-83
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    • 2006
  • In this paper, a redundancy management system for aircraft is studied, and fault detection and isolation algorithms of inertial sensor system are proposed. Contrary to the conventional aircraft systems, UAV system cannot allow triple or quadruple hardware redundancy due to the limitations on space and weight. In the UAV system with dual sensors, it is very difficult to identify the faulty sensor. Also, conventional fault detection and isolation (FDI) method cannot isolate multiple faults in a triple redundancy system. In this paper, two FDI techniques are proposed. First, hardware based FDI technique is proposed, which combines a parity equation approach with a wavelet based technique. Second, analytic FDI technique based on the Kalman filter is proposed, which is a model-based FDI method utilizing the threshold value and the confirmation time. To provide the reference value for detecting the fault, residuals are calculated using the extended Kalman filter. To verify the effectiveness of the proposed FDI methods, numerical simulations are performed.

Seismic Isolation and Response Control of Buildings in Japan

  • Masahiko Higashino;Yoshihisa Kitamura;Nagahide Kani
    • International Journal of High-Rise Buildings
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    • v.12 no.4
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    • pp.299-306
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    • 2023
  • An overview of seismic isolation and structural control in Japan is presented. The paper includes a mention of the history of aseismic technology and the earthquake threat in Japan, summarizes the merits of seismic isolation and response control, and discusses the types of devices used and some recent project examples. The projects presented are mostly examples of response control used for high-rise buildings. These types of buildings are not amendable to seismic isolation, and are a challenge to applying damping devices, as their high aspect ratio means that their dominant deformation mode is bending. Japanese engineers have developed a range of unique techniques to apply response control to these types of structures. Concluding remarks discuss some of the current challenges to expanding the use of seismic isolation and response control technologies.

Conceptual Application Schemes of Seismic Isolation Techniques to Hanok (한옥의 면진기법 적용 방안에 대한 개념적 고찰)

  • Park, Bum-Soo;Kim, Yeong-Min;Hur, Moo-Won;Lee, Sang-Hyun
    • Journal of the Architectural Institute of Korea Structure & Construction
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    • v.36 no.1
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    • pp.137-146
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    • 2020
  • In this study, various application schemes of seismic isolation system which can be applied to Hanok have been studied by analyzing its structural characteristics under seismic load. Structural stability of Hanok is more required against seismic load as Hanok becomes long-spanned and multi-storied. To meet this goal, it becomes necessary to study more advanced technology such as seismic isolation design as well as seismic control design and seismic resistant design suitable to Hanok. Seismic isolation systems have been successfully applied to RC and steel structures to improve structural performance during earthquakes. Based on these previous study, we proposed four application schemes of seismic isolation design suitable for Hanok and analyzed their structural characteristics and applicability to Hanok in conceptual level based on its structural characteristics. The proposed four schemes are base isolation method, ground isolation method, roof isolation method and intermediate-story isolation method. The applicability of the proposed method was evaluated by performing boundary nonlinear dynamic analysis to the typical Hanok for the two types of isolation method, that is, ground isolation method and roof isolation method, and the results showed that the proposed methods produced good performance enough to be applied to Hanok.

Identification of a Technique Optimized for the Isolation of Spermatogonial Stem Cells from Mouse Testes

  • Han, Na Rae;Park, Hye Jin;Lee, Hyun;Yun, Jung Im;Choi, Kimyung;Lee, Eunsong;Lee, Seung Tae
    • Journal of Embryo Transfer
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    • v.33 no.4
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    • pp.327-336
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    • 2018
  • To date, there are no protocols optimized to the effective separation of spermatogonial stem cells (SSCs) from testicular cells derived from mouse testes, thus hindering studies based on mouse SSCs. In this study, we aimed to determine the most efficient purification method for the isolation of SSCs from mouse testes among previously described techniques. Isolation of SSCs from testicular cells derived from mouse testes was conducted using four different techniques: differential plating (DP), magnetic-activated cell sorting (MACS) post-DP, MACS, and positive and negative selection double MACS. DP was performed for 1, 2, 4, 8, or 16 h, and MACS was performed using EpCAM ($MACS^{EpCAM}$), Thy1 ($MACS^{Thy1}$), or GFR ${\alpha}1$ ($MACS^{GFR{\alpha}1}$) antibodies. The purification efficiency of each method was analyzed by measuring the percentage of cells that stained positively for alkaline phosphatase. DP for 8 h, $MACS^{Thy1}$ post-DP for 8 h, $MACS^{GFR{\alpha}1}$, positive selection double $MACS^{GFR{\alpha}1/EpCAM}$, and negative selection double $MACS^{GFR{\alpha}1/{\alpha}-SMA}$ were identified as the optimal protocols for isolation of SSCs from mouse testicular cells. Comparison of the purification efficiencies of the optimized isolation protocols showed that, numerically, the highest purification efficiency was obtained using $MACS^{GFR{\alpha}1}$. Overall, our results indicate that $MACS^{GFR{\alpha}1}$ is an appropriate purification technique for the isolation of SSCs from mouse testicular cells.