• Title/Summary/Keyword: Isolation number

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A study on the characteristics of friction pendulum isolation bearings (마찰진자형 면진베어링의 특성 연구)

  • 김영중
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2000.10a
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    • pp.407-414
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    • 2000
  • The friction pendulum type seismic isolation system (FPS) has been developed to provide a simple and effective way to achieve earthquake resistance for buildings . The major advantages are: the isolation frequency can be easily achieved by designing a curvature of the surface and does not depend on the supported weight of a structure. The function of carrying vertical load is separated to the function of providing horizontal stiffness. Next the friction provides sufficient energy dissipation to protect the structure from earthquake response and resistance to the weak external disturbances such as wind load and ground vibrations due to traffic. In this paper, the friction coefficients are evaluated from number of experiments on the FPS test specimens. The relations between friction coefficient and the test waveform, velocity, and pressure are reviewed and further works are discussed.

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A New Medium for the Selective Isolation of Soil Actinomycetes (토양중 방선균의 선택적 분리를 위한 배지)

  • Cho, Seong-Hag;Hwang, Cherl-Won;Chung, Ho-Kweon;Yang, Chang-Sul
    • Microbiology and Biotechnology Letters
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    • v.22 no.5
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    • pp.561-563
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    • 1994
  • For the more effective isolation of soil actinomycetes, we have developed HHV (Hair hydrolysate-vitamin) agar medium, containing hair as the sole source of carbon and nitrogen. The HHV agar medium was superior to other media such as colloidal chintin agar, glycerol-arginine agar and starch-casein-nitrate agar, and HV (humic acid-vitamin) agar. The maximum effect of this medium has been shown in hair dry weight 0.4 g/l medium. Of each soil sample, the greatestest number of actinomycetes was isolated from the potato annual planted soil among the tested samp- les. The genus of actinomycetes isolated from the potato annual planted soil sample was identified such 5 group as Stretomyces, Micromonospora, Microbispora, Nocardia and Saccharopolyspora.

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Isolation and Determination of Alkaloids in Coptis Rhizome by Forming Complex (착체 생성에 의한 황련 알칼로이드의 분리 및 정량)

  • 임소연;김대근;신태용;임종필;엄동옥
    • YAKHAK HOEJI
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    • v.46 no.4
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    • pp.226-230
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    • 2002
  • The Coptis Rhizome is known for containing a number of isoquinoline type alkaloids. Berberine, coptisine and palmatine are the major constituents of alkaloids. The alkaloids were isolated and determined by forming complex from Coptis japonica (Ranunculaceae). For the determination of these alkaloids, a new spectrophotometric method was developed with a simple and selective sample clean-up using thiocyanatocobaltate[II] complex ion. The absorbance of alkaloidal complex in l,2-dichloroethane solution was measured at 625 nm. A calibration curve for the alkaloids isolated from Coptis Rhizome was linear over the concentration range of 0.2-0.3 mg/mι. The method proved to be rapid, simple and reliable for the isolation and the determination of the alkaloids in Coptis Rhizome.

ℋ_/ℋ Fault Detection and Isolation for Discrete-Time Delayed Systems (이산시간 상태지연 시스템을 위한 ℋ_/ℋ 고장검출 및 분리)

  • Jee, Sung-Chul;Lee, Ho-Jae
    • Journal of Institute of Control, Robotics and Systems
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    • v.17 no.10
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    • pp.960-966
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    • 2011
  • In this paper, an $\mathfrak{H}$_/$\mathfrak{H}_{\infty}$ fault detection and isolation (FDI) observer design problem is investigated for discrete-time delayed systems. To that end, a bank consisting of the sensor's number of observers is introduced. Each residual should be sensitive to a certain partial group of faults, but robust against the disturbance as far as possible. We formulate this multiobjective FDI problem as $\mathfrak{H}$_/$\mathfrak{H}_{\infty}$ observers design problem. Sufficient design condition is expressed as iterative linear matrix inequalities. The fault is then detected and isolated by evaluating the residuals through an FDI decision logic. A computer simulation is provided for verification of the proposed technique.

Architectural Improvement plans in a quarantine system for Senior facilities (노인요양시설 방역을 위한 시설 개선 방안)

  • Kang, Jeeeun;Kwon, Soonjung;Lee, Hyunjin
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.27 no.3
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    • pp.61-69
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    • 2021
  • Purpose: Senior long-term care facilities are vulnerable to a cluster infection because of frequent physical contact, large group dining, communal living, and room sharing. This study aims to provide architectural improvement plans for a quarantine system in the facilities. Methods: Actual quarantine action data, guidelines from governments and institutes, in-depth interviews with facility staff are analyzed. Results: To prevent a cluster infection in the senior facilities, it is necessary to provide an architectural plan focusing on increasing the number of single rooms and isolation rooms, providing isolation rooms for staff, separation of a soiled room from a clean room, planing an entry vestibule and a visitor's room. Implications: It is important to analyze the existing condition of facilities that had been going through cohort isolation and provide the architectural solution to strengthen infection control.

An Efficient Peer Isolation Prevention Scheme in Pure P2P Network Environments (순수 P2P 네트워크 환경에서의 효율적인 피어 고립 방지 기법)

  • Kim Young-jin;Eom Young Ik
    • The KIPS Transactions:PartC
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    • v.11C no.7 s.96
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    • pp.1033-1042
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    • 2004
  • According to the arbitration mechanism among the peers in the network, the P2P networking environments can be classified into hybrid P2P networking environments and pure P2P networking environments. In hybrid P2P networking environments, each peer gets continual services from the servers that arc operational most of the time, and so, network isolation does not occur because every peer can always keep connection to the server. In pure P2P networking environments, however, every peer directly connects to another peer without server intervention, and so, network isolation can occur when the per mediating the connection is terminated. In this paper, we propose a scheme for each peer to keep connection information of other peers by maintaining IDs of its neighbor peers, to reconnect to another peers when the mediating peer fails to work. and, for efficiency. to balance the number of connections that should be maintained by each peer. With our mechanism, each pier in the network can continuously maintain connection to the network and get seamless services from other peers. Through the simulation, we ascer-tained that network isolation does not occur in the pure P2P network adopting our mechanism and that our mechanism distributes and balances the connections that are maintained by each peer. We also analyzed the total network traffic and the mean number of hops for the connections made by each peer according to the recommended number of connections that is established at system setup time.

Construction of Probability Identification Matrix and Selective Medium for Acidophilic Actinomycetes Using Numerical Classification Data

  • Seong, Chi-Nam;Park, Seok-Kyu;Michael Goodfellow;Kim, Seung-Bum;Hah, Yung-Chil
    • Journal of Microbiology
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    • v.33 no.2
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    • pp.95-102
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    • 1995
  • A probability identification matrix of acidophilic Streptomyces was constructed. The phenetic data of the strains were derived from numerical classification described by Seong et al. The minimum number of diagnostic characters was determined using computer programs for calculation of different separation indices. The resulting matrix consisted of 25 clusters versus 53 characters. Theoretical evaluation of this matrix was achieved by estimating the chuster overlap and the identification scores for the Hypothetical Median Organisms (HMO) and for the representatives of each cluster. Cluster overlap was found to be relatively small. Identification scores for the HMO and the randomly selected representatives of each cluster were satisfactory. The matrix was assessed practically by applying the matrix to the identification of unknown isolates. Of the unknown isolates, 71.9% were clearly identified to one of eight clusters. The numerical classification data was also used to design a selective isolation medium for antibiotic-producing organisms. Four chemical substances including 2 antibiotics were determined by the DLACHAR program as diagnostic for the isolation of target organisms which have antimicrobial activity against Micrococcus luteus. It was possible to detect the increased rate of selective isolation on the synthesized medium. Theresults show that the numerical phenetic data can be applied to a variety of purposes, such as construction of identification matrix and selective isolation medium for acidophilic antinomycetes.

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Isolation of Anaerobic Bacteria from Clinical Specimens (임상검사물에서의 혐기성세균 분리)

  • Chong, Yun-Sop;Kwon, Oh-Hun;Lee, Sam-Uel Y.
    • The Journal of the Korean Society for Microbiology
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    • v.10 no.1
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    • pp.19-24
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    • 1975
  • Anaerobic bacteria are the major residents of human skin and mucous membrane. The importance, as opportunistic pathogens, of anaerobic bacteria are well recognized because of more population. with decreased defense against bacterial invasion due to chemotherapy, rediation therapy, extensive surgical operation etc. are dealt at hospitals. An analysis of the anaerobe isolation results at Yonsei University Medical Center during the January 1974-May 1975 period was made and the following results were obtained. 1) From 118 patients 146 strains of anaerobes were isolated. Among these 81.3% were nonsporforming anaerobes. Most frequently isolated anaerobes were Pc. asaccharolyticus, Ps. anaerobius, Ps. intermedius, B. fragilis and Cl. perfringens. 2) Anaerobes were frequently isolated from wound, female genital, intraabdominal, and pleuropulmonary specimens. Fewer anaerobes were isolated from blood, spinal fluid and liver specimens. 3) The ratio of anaerobe isolation to total bacteria isolation were; liver 66.7%, intraabdominal 33.3%, pleuropulmonary 28.9%, spinal fluid 5.0% and blood 4.2%. 4) Among the 118 anaerobe isolated patients, 48.3% yielded anaerobes only and rest of them yielded anaerobes together with aerobes. 5) Most of the gram-positive anaerobes were susceptible to the antibiotics tested. Exception was to tetracycline to which appreciable number showed resistance. It was noteworthy that only 48% of B. fragilis was susceptible to tetracycline.

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A novel risk assessment approach for data center structures

  • Cicek, Kubilay;Sari, Ali
    • Earthquakes and Structures
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    • v.19 no.6
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    • pp.471-484
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    • 2020
  • Previous earthquakes show that, structural safety evaluations should include the evaluation of nonstructural components. Failure of nonstructural components can affect the operational capacity of critical facilities, such as hospitals and fire stations, which can cause an increase in number of deaths. Additionally, failure of nonstructural components may result in economic, architectural, and historical losses of community. Accelerations and random vibrations must be under the predefined limitations in structures with high technological equipment, data centers in this case. Failure of server equipment and anchored server racks are investigated in this study. A probabilistic study is completed for a low-rise rigid sample structure. The structure is investigated in two versions, (i) conventional fixed-based structure and (ii) with a base isolation system. Seismic hazard assessment is completed for the selected site. Monte Carlo simulations are generated with selected parameters. Uncertainties in both structural parameters and mechanical properties of isolation system are included in simulations. Anchorage failure and vibration failures are investigated. Different methods to generate fragility curves are used. The site-specific annual hazard curve is used to generate risk curves for two different structures. A risk matrix is proposed for the design of data centers. Results show that base isolation systems reduce the failure probability significantly in higher floors. It was also understood that, base isolation systems are highly sensitive to earthquake characteristics rather than variability in structural and mechanical properties, in terms of accelerations. Another outcome is that code-provided anchorage failure limitations are more vulnerable than the random vibration failure limitations of server equipment.

Isolation and Identification of Bacillus cereus from Fermented Red Pepper-Soybean Paste (Kochujang), and Its Heat Resistance Characteristics

  • Kim, Yong-Suk;Ahn, Yong-Sun;Jeon, Do-Youn;Shin, Dong-Hwa
    • Food Science and Biotechnology
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    • v.17 no.1
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    • pp.123-129
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    • 2008
  • To isolate Bacillus cereus presenting at a level of 5 log CFU/g in kochujang, a primary dilution ($10^{-1}$) of kochujang was heated at $85^{\circ}C$ for 5 min. Two isolated strains Voges-Proskauer positive colony (KBC) and a negative colony (KBM) were identified as B. cereus and Bacillus mycoides, respectively, by biochemical test and 16S rDNA sequencing. $D_{100^{\circ}C}$-Values of KBC and KBM strains was 8.37 and 7.08 min, respectively. When spores of KBC strain were inoculated to kochujang at the level of 4-5 log spores/g, the number of spores was no significant difference (p<0.05) for each sample from 1 up to 60 day of aging. When kochujang was inoculated with 4 log spores/g and heated at $85^{\circ}C$ for 15 min, the number of spores was similar to that of unheated kochujang. Therefore, we estimated that B. cereus isolated from kochujang resistant on the heat treatment ($85^{\circ}C$, 15 min) and its heat resistance characteristics could be used to count the number in kochtjang.