• 한국의류산업학회지
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• 제5권1호
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• pp.64-70
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• 2003

Water-insoluble chitosan with molecular weight of 2,000,000, 580,000, 80,000, and 40,000 and more than 90% of degree of deacetylation were prepared to test antibacterial activity of chitosan against a pathogenic bacteria, methicillin resistant Staphylococcus aureus (MRSA). As experimental method, the Shake Flask Method (SFM) and Modified Shake Flask Method (MSFM) were applicated. The anti-microbial activity of chitosan/acetic acid aqueous solution is consistent irrespective of Mw of chitosan. MIC value of SFM measurement was 0.2 ppm, and MIC value of modified SFM measurement was 25 ppm. But MIC value of chitosan/acetic add solution and chitosan treated cotton filter paper was equally 5 ppm. The antibacterial activities of chitosan were different in different test measurements employed. The antibacterial activities of chitosan/acetic acid solution and chitosan treated cotton filter paper were also different. Therefore, it needs to be pointed out that the test measurements of anti-microbial activity have some problems.

• Earthquakes and Structures
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• 제12권5호
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• pp.501-513
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• 2017

To investigate the seismic performance of Y-shaped eccentrically braced frames fabricated with high-strength steel (Y-HSS-EBFs), a shake table test of a 1:2 scaled three-story Y-HSS-EBF specimen was performed. The input wave for the shake table test was generated by the ground motions of El Centro, Taft, and Lanzhou waves. The dynamic properties, acceleration, displacement, and strain responses were obtained from the test specimen and compared with previous test results. In addition, a finite element model of the test specimen was established using the SAP2000 software. Results from the numerical analysis were compared with the test specimen results. During the shake table test, the specimen exhibited sufficient overall structural stiffness and safety but suffered some localized damage. The lateral stiffness of the structure degenerated during the high seismic intensity earthquake. The maximum elastic and elastoplastic interstory drift of the test specimen for different peak ground accelerations were 1/872 and 1/71, respectively. During the high seismic intensity earthquake, the links of the test specimen entered the plastic stage to dissipate the earthquake energy, while other structural members remained in the elastic stage. The Y-HSS-EBF is a safe, dual system with reliable seismic performance. The numerical analysis results were in useful agreement with the test results. This finding indicated that the finite element model in SAP2000 provided a very accurate prediction of the Y-HSS-EBF structure's behavior during the seismic loadings.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.415-420
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• 2007

The objective of this study analyzes the influence of shimmy & shake phenomena due to tire design parameters which are RFV(radial force variation), DB(dynamic balance), RRO(radial run out) and air pressure. These parameters are inspection items for Q.C. after tires are manufactured. In order to analyze these parameters on this study, vehicle driving tests were achieved. The test modes are two type which are constant speed and coast-down driving. On this tests the dynamic characteristics of shimmy & shake are measured by the 3-axises accelerometers at the various positions that are knuckle(left & right), rack pinion, seat and steering wheel. In according to analyzed results, the longitudinal vibration of knuckle parts affects the lateral vibration of rack pinion and this vibration affects the lateral vibration of steering wheel that is the shimmy phenomena. Also the over and under DB by comparison with normal DB and the increment of RRO affect the occurrence of shimmy & shake phenomena.

• Clinical and Experimental Vaccine Research
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• 제11권2호
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• pp.155-162
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• 2022

Purpose: Vaccines adsorbed on aluminum adjuvants irreversibly lose potency after freezing and their safety is affected. To prevent the administration of such vaccines, the World Health Organization developed the Shake Test designed to determine whether adsorbed vaccines have been frozen or not. However, the Shake Test is difficult and time-consuming when routinely conducted at the place of vaccination. In this study, a modified shake test for prequalification of potentially frozen vaccines was elaborated. Materials and Methods: Vaccines used in the Polish Immunization Schedule were investigated and the analysis includes an assessment of precipitation time and the influence of the container type, amount and type of aluminum compound, and a volume of vaccine dose on the precipitation time. Results: Significant differences between the precipitation time of frozen and non-frozen vaccines routinely used in the Polish Immunization Schedule were observed. The precipitation time of all non-frozen vaccines was above 30 minutes. The longest precipitation time of frozen vaccines was 10 minutes. Conclusion: The finding of the study can be used in practice by the personnel administering vaccines to patients. Step-by-step recommendations for the preparation of the test have been proposed in the article.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2007년도 정기총회 및 학술발표대회
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• pp.152-155
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• 2007

Efficiency and limitations of HAZUS-MH, a GIS based systematic and informative system developed by FEMA and NIBS for natural hazard loss estimations, are discussed by means of a pilot study in the Korean Peninsular. Gyeongsang-do has been selected for the test after careful reviews of previous studies including historical and modern seismicity in the peninsular. A ShakeMap for the selected scenario earthquake with magnitude 6.7 in Gyeongju area is prepared. Then, any losses due to the scenario event have been estimated using HAZUS. Results of the pilot test show that the study area may experience significant physical, economic and social damages. Detailed study in the future will provide efficient and crucial information to the decision makers and emergency agents to mitigate any disaster posed by natural hazards.

• The International Journal of Costume Culture
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• 제2권1호
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• pp.54-61
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• 1999

The purpose of this research was first to analyse and compare the types of microbes inherent among the unwashed and washed Kupori textiles, and second to investigate whether there is a difference between unwashed and washed Kupori textiles on the susceptibility of contamination by microorganism when exposed to the same microbial environment. Microbial identification procedure and the Shake Flask Test for investigating the effect of exposure to microbial environment were carried out separately. The result of microbial identification procedure indicated that a variety of bacteria and fungi were inherent in both unwashed and washed textiles and that the population of contaminated microorganism became more diverse after washing. The result of Shake Flask Test indicated that given the same exposure condition, the unwashed textiles tend to be more susceptible to bacterial contamination than the washed textiles. The results of the present study supported the current conservation procedures adopted in Korean museums which include washing and humigation procedures before long-term storage or display of exhumed textiles.

• 대한건축학회논문집:구조계
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• 제35권10호
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• pp.143-153
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• 2019

In this study, a full scale 3-axes shake table test for M-bar and T-bar type ceilings commonly used in the country was conducted. Through damage inspection during the test, seismic performance of ceilings according to variables, such as clearance between wall mold and ceiling as well as existence of facilities, was evaluated. A test frame consisted of square hollow section members was used for the shake table test. The experimental method was performed as a fragility test using required response spectrum described in ICC-ES AC156. In the case of architectural nonstructural component that contain ceilings, it mainly is evaluated the performance by post-test visual inspection. For the evaluation of seismic performance of ceilings, this study classified and defined damaged items for targeted ceiling system referring to illustrative damage according to nonstructural performance levels accordance with ASCE 41 and previous studies. And proposed illustrative damage items classification was utilized to compare the degree of the damage according to experimental variables. The experiment results confirmed that differences in boundary conditions due to the clearance at wall mold and the installation of facilities had a significant effect on the seismic performance of the ceiling.

• Earthquakes and Structures
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• 제15권6호
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• pp.595-603
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• 2018

Shake table testing has been regarded as one of the most effective experimental approaches to evaluate seismic response of structural systems subjected to earthquakes. However, reproducing a prescribed acceleration time history precisely over the frequency of interest is challenging because shake table test systems are eventually nonlinear by nature. In addition, interaction between the table and specimen could affect the control accuracy of shake table testing significantly. Various novel control algorithms have been proposed to improve the control accuracy of shake table testing; however, reference values for control performance assessment remain rare. In this study, reference values for control performance assessment of shake table testing are specified based on the statistical analyses of 1,209 experimental data provided by the Seismic Simulator Laboratory of National Center for Research on Earthquake Engineering in Taiwan. Three individual reference values are considered for the assessment including the root-mean-square error of the achieved acceleration time history; the percentage of the spectral acceleration that exceeds the determined tolerance range over the frequency of interest; and the error-ratio of the achieved peak ground acceleration. Quartiles of the real experimental data in terms of the three objective variables are obtained, providing users with solid and simple references to evaluate the control performance of shake table testing. Finally, a set of experimental data of a newly developed control framework implementation for uni-axial shake tables are used as an application example to demonstrate the significant improvement of control accuracy according to the reference values provided in this study.

• Earthquakes and Structures
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• 제16권6호
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• pp.665-677
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• 2019

This study utilizes large-scale shake table test to investigate the seismic performance of an isolated bridge with lead rubber bearings crossing an active fault. Two transverse restraining systems with and without shear keys are tested by applying spatially varying ground motions. It is shown that the near-fault span exhibits larger bearing displacement than the crossing-fault span. Bridge piers away from the fault rupture are more vulnerable than those adjacent to the fault rupture by attracting more seismic demand. It is also verified that the shear keys are effective in restraining the bearing displacement on the near-fault span, particularly under the large permanent ground displacement.

• Computers and Concrete
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• 제33권2호
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• pp.195-204
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• 2024

Floor inertial forces are transferred to lateral force resisting systems through a diaphragm action during earthquakes. The diaphragm action requires floor slabs to carry in-plane forces. In precast concrete diaphragms, these forces must be carried across the joints between precast floor units as they represent planes of weakness. Therefore, diaphragm reinforcement with sufficient strength and deformability is necessary to ensure the diaphragm action for the floor inertial force transfer. In a shake table test for a three-story precast concrete structure, an unexpected local failure in the diaphragm flexural reinforcement occurred. This failure caused loss of the diaphragm action but did not trigger collapse of the structure due to a possible alternative path for the floor inertial force transfer. This paper investigates this failure event and its impact on structural seismic responses based on the shake table test and simulation results. The simulations were conducted on a structural model with discrete diaphragm elements. The structural model was also validated from the test results. The investigation indicates that additional floor inertial force will be transferred into the gravity columns after loss of the diaphragm action which can further result in the increase of seismic demands in the gravity column and diaphragms in adjacent floors.