• Journal of the Korean Society of Propulsion Engineers
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• v.20 no.4
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• pp.87-93
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• 2016

In a Direct Connect(DC) mode altitude engine test, a labyrinth seal is set up between an air intake duct and an engine. The labyrinth seal plays a key role in mechanically isolating them, which contributes to the accurate measurement of thrust and the other component forces. However, when high vertical temperature gradient is generated in the supplied air in the duct, the isolation breaks down. In this paper, a labyrinth seal control device is designed and installed in an effort to eliminate the issue. Test result shows the device successfully gets rid of the contact problem even when high vertical temperature gradient is produced.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.5
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• pp.764-768
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• 2010

Three different isolation media for Cronobacter sakazakii have been recommended by Korea Food and Drug Administration from 2007. Performance comparison test was carried out between recommended Cronobacter sakazakii isolation medium. Chromogenic Enterobacter sakazakii agar (CESA) and Enterobacter sakazakii agar (ESA) produce more distinctive colonies having characteristic colors and appearance than Violet red bile glucose agar (VRBGA). The sensitivity and specificity of 3 different isolation media was checked. All 3 tested media showed 100% sensitivity when tested with 30 different Cronobacter sakazakii. The CESA and ESA showed 100% specificity when tested with Enterobacteriaceae except Cronobacter sakazakii, However, VRBGA did not show any specificity, showing inadequate selectivity compared to applicable Cronobacter sakazakii isolation medium. Artificially inoculated Cronobacter sakazakii to milk powder was easily recovered with 3 different isolation media and they all showed almost the same recovery activity.

• The Korean Journal of Rehabilitation Nursing
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• v.14 no.1
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• pp.5-12
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• 2011

Purpose: The purpose of this study was to evaluate the association among of Activity of Daily Living (ADL), Instrumental Activities of Daily Living (IADL), depression and isolation in disabled people. Method: The subjects consisted of 761 disabled people in Korea. Data were analyzed using descriptive statistics, t-test, ANOVA, and Pearson's correlational statistics. Results: There were significant differences in age, cause of disability, type of disability, degree of disability, education, job, perceived health condition, and economic status between disabled people with high and low levels of ADL and IADL. Depression showed significant differences in type of disability, degree of disability, education, job, perceived health condition, and economic state; isolation showed significant differences in age, cause of disability, type of disability, education, job, residence, perceived health condition, and economic status. A significant association was identified between depression and isolation (r=.69, p<.001). Conclusion: There was a high incidence of depression in disabled men with high levels of isolation and ADL and IADL dependence. An effort to increase disabled people's ADL, IADL, and independence levels is needed, and nursing interventions should be designed and tested to increase their community involvement and decrease the sense of isolation and depression.

• Earthquakes and Structures
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• v.27 no.2
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• pp.143-154
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• 2024

Friction pendulums typically suffer from poor uplift-restraining. To improve the uplift-restraining and enhance the energy dissipation capacity, this article proposed a composite isolation device based on electromagnetic forces. The device was constructed based on a remote control system to achieve semi-active control of the composite isolation device. This article introduces the theory and design of an electromagnetic chuck-friction pendulum system (ECFPS) and derives the theoretical equation for the ECFPS based on Maxwell's electromagnetic attraction equation to construct the proposed model. By conducting 1:3 scale tests on the electromagnetic device, the gaps between the practical, theoretical, and simulation results were analyzed, and the accuracy and effectiveness of the theoretical equation for the ECFPS were investigated. The hysteresis and uplift-restraining performance of ECFPS were analyzed by adjusting the displacement amplitude, vertical load, and input current of the simulation model. The data obtained from the scale test were consistent with the theoretical and simulated data. Notably, the hysteresis area of the ECFPS was 35.11% larger than that of a conventional friction pendulum. Lastly, a six-story planar frame structure was established through SAP2000 for a time history analysis. The isolation performances of ECFPS and FPS were compared. The results revealed that, under horizontal seismic action, the horizontal seismic response of the bottom layer of the ECFPS isolation structure is greater than that of the FPS, the horizontal vibration response of the top layer of the ECFPS isolation structure is smaller than that of the FPS, and the axial force at the bottom of the columns of the ECFPS isolation structure is smaller than that of the FPS isolation structure. Therefore, the reliable uplift-restraining performance is facilitated by the electromagnetic force generated by the device.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1995.04a
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• pp.122-129
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• 1995

The seismic behavior of a rectangular liquid container with high damping laminated rubber bearing is investigated through the scaled model tests. The results are compared with those for non-isolated model, and those by analytical methods. It is shown that the optimum dynamic properties of isolation system can reduce the acceleration response in the superstructure significantly and prevent the amplification of sloshing height.

• Journal of the Korea Institute of Military Science and Technology
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• v.2 no.1
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• pp.82-89
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• 1999

In this article, the performances of acoustic enclosure with double resilient mount system which was designed by ADD to reduce the radiated noise by main noise source of ships, was tested and evaluated. From test results, it was verified that the acoustic performances of acoustic enclosure satisfied the requirements; vibration isolation level at 1st stage mount system of 15 ㏈ and airborne noise reduction level of 20 ㏈ in broad band.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.32.3-32
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• 2002

We analyze the effect of main inertial sensor errors such as, misalignment, scale factor error and bias on the performance of modified sequential probability ratio test (SPRT) for sequential fault detection and isolation (FDI). The inertial sensor errors cause the modified SPRT method to give false alarm. We use a two-stage KF to obtain a modified parity vector with which the inertial sensor errors can be removed and thus modified SPRT method can be used regardless of inertial sensor errors.

• Nuclear Engineering and Technology
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• v.41 no.1
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• pp.53-62
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• 2009

A set of experiments has been conducted on the performance sensitivity of the passive residual heat removal system (PRHRS) for an advanced integral type reactor, SMART, by using a high temperature and high pressure thermal-hydraulic test facility, the VISTA facility. In this paper the effects of the opening delay of the PRHRS bypass valves and the closing delay of the secondary system isolation valves, and the initial water level and the initial pressure of the compensating tank (CT) are investigated. During the reference test a stable flow occurs in a natural circulation loop that is composed of a steam generator secondary side, a secondary system, and a PRHRS; this is ascertained by a repetition test. When the PRHRS bypass valves are operated 10 seconds later than the secondary system isolation valves, the primary system is not properly cooled. When the secondary system isolation valves are operated 10 or 30 seconds later than the PRHRS bypass valves, the primary system is effectively cooled but the inventory of the PRHRS CT is drained earlier. As the initial water level of the CT is lowered to 16% of the full water level, the water is quickly drained and then nitrogen gas is introduced into the PRHRS, resulting in the deterioration of the PRHRS performance. When the initial pressure of the PRHRS is at 0.1MPa, the natural circulation is not performed properly. When the initial pressures of the PRHRS are 2.5 or 3.5 MPa, they show better performance than did the reference test.

• Korean Journal of Veterinary Research
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• v.27 no.1
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• pp.61-68
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• 1987

This study was conducted to determine the microorganisms inhabitating in cow genitalia and their antimicrobial drug susceptibility. During the period between July, 1985 and February, 1986, a total of 111 cow genitalia, 58 from Korean native and 53 from dairy cow, were sampled at three abattoirs. Gross pathological examination and bacterial isolation and identification were performed from the genital samples. In addition antimicrobial drug susceptibility test for the microorganisms isolated, some synergistic activity among drugs were examined on the major organism isolated from the cases of endometritis and pyometra. The results are summerized as follows: 1. Among the bacteria isolated from the genitalia, Staphylococcus spp., C. pyogenes, E. coli, Proteus spp., Streptococcus spp., Bacillus spp. were most frequently isolated whereas the genera of Pasteurella, Pseudomonas, Klebsiella and Yersina were detected far less frequently. 2. In Korean native cow the genera of Straphylococcus and Steptococcus were more isolated than dairy cow while in dairy cow the genera of Corynebacterium, Proteus, Escherichia were more of ten isolated than Korean native cow. 3. From cow genital organs showing lesions of endometritis and prometra, C. pyogenes was most frequently isolated, the isolation rate being 60 percent, and follow by Staphylococcus spp., Proteus spp., E. coli and Pasteurella spp. in the order. 4. Antimicrobial drug susceptibility test conducted on the major organisms isolated showed that all the isolates were susceptible to gentamicin, cephalosporin and sulfisoxazole, but resistant to tetracycline and penicillin. 5. Twenty-nine isolates of C. pyogenes were submitted to the synergistic activity test of cephalosporin, kanamycin and streptomycin with penicillin. Synergists were demonstrated in 90 percent, 31 percent and 27 percent of isolates examined by the combined use of penicillin and cephalosporin, penicillin and kanamycin, penicillin and streptomycin, respectively. About 10 percent of the isolates were found to be indifferent by the synergism test.

• Journal of the Earthquake Engineering Society of Korea
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• v.24 no.4
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• pp.157-167
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• 2020

In this study, a field bridge test was conducted to find the dynamic properties of cable supported bridges with resilient-friction base isolation systems (R-FBI). Various ambient vibration tests were performed to estimate dynamic properties of a test bridge using trucks in a non-transportation state before opening of the bridge and by ordinary traffic loadings about one year later after opening of the bridge. The dynamic properties found from the results of the tests were compared with an analysis model. From the result of the ambient vibration tests of the cable supported bridge with R-FBI, it was confirmed that the dynamic properties were sensitive to the stiffness of the R-FBI in the bridge, and the seismic analysis model of the test bridge using the effective stiffness of the R-FBI was insufficient for reflecting the dynamic behavior of the bridge. In the case of cable supported bridges, the seismic design must follow the "Korean Highway Bridge Design Code (Limit State Design) for Cable supported bridges." Therefore, in order to reflect the actual behavior characteristics of the R-FBI installed on cable-supported bridges, an improved seismic design procedure should be proposed.