• Journal of The Korea Institute of Healthcare Architecture
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• v.22 no.3
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• pp.45-56
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• 2016

Purpose: The MERS(Middle East Respiratory Syndrome) outbreaks in Korea highlighted dramatically the failings of traditional hospital environment for controlling or preventing infections among both patients and healthcare workers. MERS is transmitted by droplets that can be airborne over a limited area. The point should be emphasized that MERS in South Korea was predominantly a hospital-acquired (not a community-acquired) infection, because approximately 93% of MERS cases were resulted from exposure in hospital settings. This paper tries to suggest the design guidelines of negative pressured isolation ward for the sake of proper control of severe respiratory infectious diseases. Methods: Literature survey on the design guideline and regulations of airborne infection wards in Korea, Europe U.K. and CDC of U.S. have been carries out. 4 special infection wards in Hongkong, Germany, Japan and Korea have been surveyed in order to make the best use of the experiences related to facility design and operations. Results: Operating system influencing the facility design, space organizations of infectious ward including required space and zoning, and circulations of patients, staffs and materials are proposed. Implications: The results of this paper can be the basic data for the design of the airborne infection ward and relevant regulations. Afterwards in-depth study such as the development of space standards for the single bedroom, locker room and so on could be explored.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.7
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• pp.280-292
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• 2016

This descriptive survey assessed knowledge of intensive care unit (ICU) nurses regarding compliance with infection control for six kinds of multi-drug resistant organisms to assist in development of effective intervention strategies. Participants included 210 nurses working in the ICUs of general hospitals who completed a structured questionnaire. The results showed that the nurses' knowledge level and infection control compliance was 10.54 and 3.39 for MRSA; 11.25 and 3.69 for VRE; and 9.60 and 3.49 for CRGNB, respectively[ED highlight - consider providing additional information to describe what these values indicate.]. Knowledge regarding MRSA infection control differed significantly based on age, clinical experience, and experience as a trainee, while compliance with MRSA infection control differed based on age. Knowledge regarding VRE infection control was significantly different based on academic qualification level, experience as a trainee, and whether guidelines existed, while compliance with VRE infection control differed based on academic qualification level and the presence of an isolation environment. Knowledge regarding CRGNB infection control differed significantly based on academic qualification level and experience as a trainee, while compliance with CRGNB infection control differed based on the presence of an isolation environment. Thus, intervention strategies should include education programs for enhancing ICU nurse' knowledge regarding strategies for creating isolation environments.

• Fire Science and Engineering
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• v.34 no.1
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• pp.135-141
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• 2020

The first case of Middle East Respiratory Syndrome (MERS) was reported in Korea in 2015, after a Korean man from Bahrain tested positive for the infection. After first eruption, there were numbers of secondary infectees and whole country were frightened. At the time, isolated ambulances were available but few, and there was no specific way to prevent contamination during transfer. Therefore, Seoul National University Hospital and the University of Seoul developed isolation units and air filters. Four years after the MERS outbreak, this study measured the differential pressure inside and outside the small isolation units based on the differential pressure and air flow derived from simulation and testing, and proposed minimum values for virus leakage and internal sealing. A performance evaluation and testing method for the transfer equipment is proposed. The critical function of the small isolated transport equipment was defined and selected as an evaluation item; performance evaluation was carried out by simulating a real-world case. The results provide the proper pressure configuration of positive and negative pressure inside the segregation feeder; the clear criteria for the HEPA filter; and the performance criteria for the segregation feeder and air purifier.

• Journal of The Korea Institute of Healthcare Architecture
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• v.26 no.3
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• pp.17-26
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• 2020

Purpose: This paper presents research evidence that the environmental design of the doffing area in a biocontainment unit (BCU) can have a measurable impact on increasing the safety of frontline healthcare workers (HCW) during doffing of high-level personal protective equipment (PPE), and proposes optimized biocontainment unit design. Methods: From 2016 to 2019, The SimTigrate Design Lab conducted 3 consecutive studies, focusing on ways in which the built environment may support or hinder safe doffing. In the first study, to identify the risky behaviors, we observed 56 simulation exercises with HCWs in 4 BCUs and 1 high-fidelity BCU mockup. In the second study, we tested the effectiveness of a redesigned doffing area on improving the HCWs performance and used simulation, observation, and rapid prototyping in 1 high-fidelity mockup of a doffing area. In a follow-up study, we used simulation and co-design with HCWs to optimize the design of a safer doffing area in a full-size pediatric BCU mock-up. Results: We identified 11 specific risky behaviors potentially leading to occupational injury, or contamination of the PPE, or of the environment. We developed design strategies to create a space for safer doffing. In the second study, in a redesigned doffing area, the overall performance of HCW improved, and we observed a significant decrease in the number of risky behaviors; some risky behaviors were eliminated. There was a significant decrease in physical and cognitive load for the HCWs. Finally, we propose an optimized layout of a BCU for a safer process of PPE doffing. Implications: The proposed BCU design supports better staff communication, efficiency, and automates safer behaviors. Our findings can be used to develop design guidelines for spaces where patients with other highly infectious diseases are treated when the safety of the patient-facing HCWs is of critical importance.

• Journal of Microbiology and Biotechnology
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• v.9 no.4
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• pp.429-435
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• 1999

An adenosine 5'-monophosphate deaminase (AMP aminohydrolase, EC 3.5.4.6) was purified to homogeneity from the cell-free extract of Saccharomyces cerevisiae DKCTC7248. The molecular mass of subunit was estimated to be 80 kDa on SDS-PAGE, and that of the holoenzyme was shown to be 240 kDa by gel filtration. The isoelectric point of the enzyme (AMP deaminase D) was determined to be 6.2. The AMP deaminase D was specific towards AMP with an apparent $K_m$ value of 4.1 mM and a Hill coefficient, $n_H$, of 2.2. Both ATP and ADP were positive allosteric effectors of the AMP deaminase D: The apparent $K_{m}$ was decreased to 1.6 mM and 3.3 mM in the presence of 0.1 mM ATP and ADP, respectively, lowering $n_{H}$ to 1.0. Univalent cations like $K^+, Na^+ and Li^ +$ activated the enzyme but some divalent cations such as $Cu^{ 2+} and Cd^{2+}$ showed strong inhibitory effects. This enzyme displayed optimum activity at $30^{\circ}C$ and pH 7.0. In addition, it was stable up to $45^{\circ}C$ and over a wide pH range(pH 5.5-9.0). Amino acid sequences of its N-terminal region were analyzed to be ADYKMQMFADDA.

• Journal of Microbiology and Biotechnology
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• v.22 no.5
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• pp.699-707
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• 2012

Since the 2009 pandemic human H1N1 influenza A virus emerged in April 2009, novel reassortant strains have been identified throughout the world. This paper describes the detection and isolation of reassortant strains associated with human pandemic influenza H1N1 and swine influenza H1N2 (SIV) viruses in swine populations in South Korea. Two influenza H1N2 reassortants were detected, and subtyped by PCR. The strains were isolated using Madin-Darby canine kidney (MDCK) cells, and genetically characterized by phylogenetic analysis for genetic diversity. They consisted of human, avian, and swine virus genes that were originated from the 2009 pandemic H1N1 virus and a neuraminidase (NA) gene from H1N2 SIV previously isolated in North America. This identification of reassortment events in swine farms raises concern that reassortant strains may continuously circulate within swine populations, calling for the further study and surveillance of pandemic H1N1 among swine.

• Journal of Microbiology and Biotechnology
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• v.8 no.2
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• pp.171-177
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• 1998

The strain A49, which produces a new type of extracellular polysaccharide was isolated from soil samples. From morphological, physiological and biochemical tests, the strain A49 was identified as a Bacillus polymyxa and named Bacillus polymyxa A49. Bacillus polymyxa A49 was found to produce a highly viscous extracellular polysaccharide when grown aerobically in a medium containing glucose as the sole source of carbon. The polysaccharide (A49 POL) showed a homogeneous pattern on gel permeation chromatography (GPC) and its molecular weight was estimated to be about 1.6 mega dalton (mDa). The FT-IR spectrum of A49-POL revealed typical characteristics of polysaccharides. As a result of investigations with HPLC and carbozole assay, A49-POL was found to consist of L-fucose, D-galactose, D-glucose, D-mannose, and D-glucuronic acid, with the molar ratio of these sugars being approximately 1:2:7:50:12. Rheological analysis of A49 POL revealed that it is pseudoplastic and has a higher apparent viscosity at dilute concentrations than does xanthan gum. The consistancy factor of A49 POL was found to be higher, and the flow index of A49 POL lower, than xanthan gum. Its apparent viscosity was comparatively unstable at various temperatures. the A49 POL showed the highest apparent viscosity at pH 3. When salts were added to A49 POL solution, the solution was compatible with up to 10% KCl, 35% NaCl, 55% $CaCl_2$, 55% $MgCl_2$, 55% $K_2HPO_4$, and 110% $Ca({NO_3})_2$, respectively.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.2
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• pp.194-201
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• 2010

We propose a frequency selective surface(FSS) using double split ring resonators(DSRRs) for isolation enhancement between CDMA and RFID. The structure consists of an outer SRR and an inner SRR, and the gaps are formed in the same direction. By properly adjusting the gap and line width, the resonant frequency and skirt characteristics can be adjusted without varying the unit cell size. The proposed structure has a different field distribution from that of an ordinary SRR for magneto-dielectric materials. One layer consists of $9{\times}9$ unit cells and the other layer was separated by 50 mm. To validate the simulation results, we fabricated the patch antenna and the FSSs, and the measured results show a good agreement with the simulated ones. The electrical size of the unit cell is $0.110\;{\lambda}{\times}0.110\;{\lambda}{\times}0.002\;{\lambda}$, and the size of the two layer FSS is $1.058\;{\lambda}{\times}1.058\;{\lambda}{\times}0.153\;{\lambda}$. The two layer FSS maintain gain in CDMA frequency and has 6.9 dB reduced gain in RFID frequency.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.6
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• pp.226-234
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• 2021

The objective of this study is to establish the fundamental design data for axial load-displacement relationship under axial monotonic or cyclic responses of seismic damping·isolation (SDI) units developed for ceiling structures. The main parameters include the installation of a spring, the number of rubber layer, prestress stress of bolts for connector between the spring and rubbers, and loading type. Test results showed that SDI units with a spring in the core and higher prestress stress of bolts tended to be higher stiffness at the ascending branch and more ductile behavior at the descending branch. This trends more notable for the specimens under monotonic load rather than cyclic loads. Consequently, the energy dissipation of SDI unit can be optimally designed with the following conditions: installation of a spring within 3-layer rubbers and prestress applied to the bolts at 10% of their yielding strength . When compared with the experimental tension capacity of the developed SDI units, the predictions by JIS B 2704-1 and KDS 31 00 are conservative under monotonic loading but higher by approximately 10% under cyclic loading.

• KIEAE Journal
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• v.11 no.5
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• pp.55-67
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• 2011

The purpose of this research is to find applicable design characteristics and methods of communal spaces in vertical urban multi-family housing. With this goal, several overseas' multi-family housing projects are selected and their communal spaces are identified. The design characteristics of the communal spaces are analyzed with a special focus on the territories such as an individual unit boundary, building interior and exterior boundary. In terms of the framework for analysis, territoriality, openness, and unique characteristics are reviewed. As a result, the communal spaces are created using various spatial composition methods such as addition, subtraction, connection, extension, accumulation, and isolation. The communal space programs are integrated in plans and sections throughout the buildings. Visual openness and connection with surrounding urban environments are articulated by void spaces, transparent and translucent building materials, green spaces, and applications of graphical images. Communal identities and aesthetics are emphasized by unique building forms and space arrangements. The uses of finish materials, colors, objects, and images add strong characters to the communal spaces. For a further research, it is necessary to combine a design method study with residents' behaviors and community interactions.