• Journal of the Earthquake Engineering Society of Korea
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• v.23 no.4
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• pp.231-238
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• 2019

A conventional lumped-mass stick model is based on the tributary area method to determine the masses lumped at each node and used in earthquake engineering due to its simplicity in the modeling of structures. However the natural frequencies of the conventional model are normally not identical to those of the actual structure. To solve this problem, recently an updated lumped-mass stick model is developed to provide the natural frequencies identical to actual structure. The present study is to investigate the seismic response accuracy of the updated lumped-mass stick model, comparing with the response results of the shaking table test. For the test, a small size four-story steel frame structure is prepared and tested on shaking table applying five earthquake ground motions. From the comparison with shaking table test results, the updated model shows an average error of 3.65% in the peak displacement response and 9.68% in the peak acceleration response. On the other hand, the conventional model shows an average error of 5.15% and 27.41% for each response.

• Nuclear Engineering and Technology
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• v.55 no.9
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• pp.3342-3351
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• 2023

High-density polyethylene (HDPE) pipelines in nuclear power plants (NPPs) have to meet high requirements for seismic performance. HDPE pipes have been proved to have good seismic performance, but joints are the weak links in the pipelines, and pipeline failures usually initiate from the defects inside the joints. Limited data are available on the seismic performance of butt-fusion joints of HDPE pipelines in NPPs, especially in terms of defects changes inside the joints after earthquakes. In this paper, full-scale shaking table tests were performed on a test section of suspended HDPE pipelines in an NPP, which included straight pipes, elbows, and 10 butt-fusion joints. During the tests, the seismic load-induced strain of the joints was analyzed by strain gauges, and it was much smaller than the internal pressure and self-weight-induced strain. Before and after the shaking table tests, phased array ultrasonic testing (PA-UT) was conducted to detect defects inside the joints. The locations, numbers, and dimensions of the defects were analyzed. It was found that defects were more likely to occur in elbows joints. No new defect was observed after the shaking table tests, and the defects showed no significant growth, indicating the satisfactory seismic performance of the butt-fusion joints.

• Korean Journal of Poultry Science
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• v.19 no.1
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• pp.1-12
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• 1992

This study was divided into experiment I(129g egg-albumen plus 150g sucrose) and experiment II(161g egg-albumen plus 150g sucrose) which were subdivided into groups treated with 0, 8.71, 17.43 and 26.149 egg yolk. These experiments were incubated in a shaking water bath(5$0^{\circ}C$) with a speed of 92(turnaround) per minute for a period of times. The pH and specific gravity were measured after 2, 4, 6, 8, 10 and 12 hour incubations. The results obtained were as follows： 1. The pH and specific gravity were steadily increased by shaking time, but variably was influenced by the amount of egg yolk and egg-albumen. 2. In the groups treated with egg-albumen, egg yolk, and sucrose of experiments I and II, pH was increased by the amount of egg-albumen in conjunction with shaking time, but specific gravity was decreased. 3. Ten hours after shaking maximum pH 8.60 was shown in the groups treated with 161g egg-albumen ： however, in ：he groups treated with 129g egg-albumen the maximum pH 8.39 was shown 12 hours after shaking. The different time exhibited maximum pH resulted from the amount of egg-albumen used. 4. The pH specific gravity were higher in the ,groups treated without egg yolk than in the groups with egg yolk. 5. In the experiment I which was added four levels of egg yolk to 1509 of sucrose and 129g of egg albumen, specific gravity(Table 2) had a high (r＝0.9692$^{* *}$) correlation with pH (Table 1) and the regression equation between specific gravity and pH (X) was Y＝0.050＋0.145x. 6. In the experiment II which was added four levels of egg yolk to 150g of sucrose and 161g of egg albumen, specific gravity(Table 4) had a high (r＝0.8963$^{* *}$) correlation with pH (Table 3) and the regression equation between specific gravity and pH (X) was Y＝0.294＋0.110X.10X.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.546-551
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• 2006

This study is concerned with the dynamic behaviour of a fluid layer and a submerged deposit of sand in a rigid rectangular container when subjected to horizontal shaking. Detailed analyses are made of the interaction between the fluid pressure field and the excess pore pressure changes in the sand deposit, in terms of finite-element modelling as well as of two-layer fluid theory. It is shown that the predicted performance compares favourably with what has been observed in centrifugal shaking-table testing on submerged sand deposits.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1998.04a
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• pp.188-195
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• 1998

The main objective of this study is to observe the effect of visco-elastic damper on seismic behavior of structure. A small shaking table was designed and manufactured using the materials and machinery available in the market by the authors. Also, two small-scale models with and without visco-elastic dampers were made. Dynamic characteristics, such as natural periods and damping ratios, were measured with free vibration tests. Finally, the earthquake simulations tests by using this shaking table were performed to these models. Based on the test results, the effect of visco-elastic damper on the seismic response of models is evaluated.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.529-537
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• 2005

This paper proposes the shaking table testing method, without any soil specimen only using building model as an experimental part, considering dynamic soil-structure interaction based on the substructure method. The two-layered soil is assumed as a soil model of the entire soil-structure interaction syhstem(SSI) in this paper. Differently from the constant soil stiffness, the frequency-dependent dynamic soil stiffness is approximated for the case of both acceleration and velocity feedback, respectively. The interaction force is observed from measuring the accelerations at superstructure. Using the soil filters corresponding to the approximated dynamic soil stiffness, the shaking table drives the acceleration or velocity, which the needed motion to give the building specimen the SSI effects. Experimental results show the applicability the proposed methodologies to the shaking table test considering dynamic soil-structure interaction.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.5
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• pp.845-848
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• 1994

The fermenting conditions for acetic acid production with Acetobacter sp. FM-10 which could grow in the medium containing 10% ehtanol were investigated. Initial concentration of acetic acid in broth medium affected greatly to the fermentation speed. For example , the acetic acid production increased proportionally by the increasing of initial concentration was higher that 1.0%. When the cultivation was started with broth medium containing 5% ethanol, the additional adding ethanol during the fermentation was not significantly increased the acidity of the medium. The acidity of the medium containing 10% ethanol was reached to 8.3% after shaking than static cultivation by about 10 days with 150 rpm shaking speed. Acetic acid production with shaking cultivation was faster the static cultivation by abot 10 days under the same condition except shaking. In acetic acid fermentation with the batch style fermentor , the optimum fermentation condition was 700 rpm of agitation speed and 5L/min air flow rate in 3L culture medium .

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.1
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• pp.138-142
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• 2001

Solid contents, free sugars, phenlic compounds and glycyrrhizin of extracts obtained from by-products of Glycyrrhizia uralensis by three different methods, i.e., shaking, heating, and static methods, were determined. Solid contents of extracts obtained by shaking, heating and static method were 15.6%, 15.0% and 5.3%, respectively. Phenolic compound contents of them were 11.33 mg/100 mL, 11.21 mg/100mL and 10.15 mg/100 mL. Main free sugars in the extracts from the by-products of G. uralensis were fructose, glucose, sucrose, and maltose. Glycyrrhizin content of the extracts from the by-products of G. uralensis were 2.79%, 3.54% and 0.63%, respectively. Extract obtained by the shaking methods had an ability of donating electron to DPPH. The relative antioxidant effects of th extract obtained from the shaking method showed 70% inhibitory effect of peroxidation on egg yolk lecithin.

• Structural Engineering and Mechanics
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• v.48 no.2
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• pp.151-171
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• 2013

The current paper presents the numerical blind prediction of nonlinear seismic response of two full-scale, three dimensional, one-story reinforced concrete structures subjected to bidirectional earthquake simulations on shaking table. Simulations were carried out at the laboratories of LNEC (Laboratorio Nacional de Engenharia Civil) in Lisbon, Portugal. The study was motivated by participation in the blind prediction contest of shaking table tests, organized by the challenge committee of the 15th World Conference on Earthquake Engineering. The test specimens, geometrically identical, designed for low and high ductility levels, were subjected to subsequent earthquake motions of increasing intensity. Three dimensional nonlinear analytical models were implemented and subjected to the input base motions. Reasonably accurate reproduction of the measured displacement response was obtained through appropriate modeling. The goodness of fit between analytical and measured results depended on the details of the analytical models.

• International Journal of High-Rise Buildings
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• v.1 no.3
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• pp.221-228
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• 2012

Shanghai Tower is a super high-rise building of 632 m height with 'mega frame-core- outrigger truss' structure system. Due to the complexity and irregularity of structure, shaking table test was carried out to investigate its seismic performance. A 1/40 scaled test model was designed, built and tested on shaking table under earthquake of small, moderate and large levels. The experimental results showed that the structure can meet the requirements of Chinese codes and reach scheduled performance objectives. Elastic and plastic time-history analysis on the structure were carried out and the results were compared to experimental results. Based on the research results some suggestions were proposed to contribute favorable effect on the seismic capacity of the structure.