• Applied Biological Chemistry
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• v.18 no.3
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• pp.177-182
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• 1975

The analysis of Jerusalem artichoke showed that it contains 12.09% of Inulin. The results obtained from the examination of the conditions for fructose production by cultivating Pencillum sp 1 in the Jerusalem articoke medium were as follows: 1. The optimum amount of water added to Jerusalem artichoke was 2.5 $\ell$ of distilled water per ㎏ of fresh Jerusalem artichoke. It this case, the concentration of Inulin was 4% (w/v). 2. The optimum temperature was $30^{\circ}C$, the initial optimum pH was 5.0 and the optimum cultural period was 72 hours. 3. Shaking culture with 50 ml of the medium and 120 oscills/min in 500 ml shaking flask was most effective as the culture method. 4. 0.1% of $NH_4H_2PO_4$ as a nitrogen source, 0.001 of $FeSO_47H_20$ and 0.001% of $MgSO_47H_2$ as metal salts were most effective. 5. Fructose production continued to increase for 72 hours under the optimum conditions for cultivation and the highest production rate to the Inulin was 95.25%.

• Earthquakes and Structures
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• v.19 no.1
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• pp.17-28
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• 2020

In this paper, a modified and improved seismic isolation system called suspension columns for seismic isolation was investigated. An experimental study of the proposed isolation method, together with theoretical and numerical analyses, has thoroughly been conducted. In the proposed method, during the construction of the foundation, some cavities are created at the position of the columns inside the foundation and the columns are placed inside the cavities and hanged from the foundation by flexible cables rather being directly connected to the foundation. Since the columns are suspended and due to the gap between the columns and walls of the cavities, the structure is able to move freely to each side thus, the transmitted seismic actions are reduced. The main parameter of this isolation technique is the length of the suspension cable. As the cable length is changed, the natural frequency of the structure is also changed, thus, the desired frequency can be achieved by means of an appropriate cable length. As the experimental phase of the study, a steel frame structure with two floors was constructed and subjected to the acceleration of three earthquakes using a shaking table with different hanging cable lengths. The structural responses were recorded in terms of acceleration and relative displacement. The experimental results were compared to the theoretical and numerical ones, obtained from the MATLAB programming and the finite element software ABAQUS, showing a suitable agreement between them. The results confirm the effectiveness of the proposed isolation method in reducing the seismic effects on the structure.

• Journal of the Korean Geotechnical Society
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• v.21 no.8
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• pp.55-61
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• 2005

Mononobe-Okabe method is generally used to evaluate dynamic earth pressure for the seismic design of retaining walls. However, Mononobe-Okabe method does not consider the effects of dynamic interactions between backfill soil and walls. In this research, shaking table tests on retaining walls were performed to analyze the phase and magnitude of dynamic earth pressure. The unit weight of walls, the amplitude of input acceleration and the base friction coefficient of walls were varied to analyze the influence of these factors on the dynamic earth pressure. Test results showed that the dynamic earth pressure was 180 degrees out of phase with the wall inertia force for the low sliding velocity of the wall, whereas small peaks of the dynamic earth pressure, which are in phase with the wall inertia force, were developed for the high sliding velocity of the wall. The amplitude of dynamic earth pressure was proportional to that of wall acceleration and the unit weight of the wall. In addition, the dynamic earth forces calculated by the Mononobe-Okabe method were the upper limit of the dynamic earth pressures.

• Korean Journal of Microbiology
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• v.12 no.1
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• pp.25-30
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• 1974

It was convinced that with a relatively small capital investment and with a low operating cost, appreciable amounts of cement copper could be produced from low-grade minerals by the application of a bacterial leaching method. For the recovery of cement copper from the impure pregnant solution, direct precipitation of copper with tin plates by a bacterial leaching method was feasible. The results obtained were as follows: 1)In order to remove the cement copper from the reducing metal, aeration and agitation method were more effective and economic than shaking method. 2)The rate of copper recovery from the pregnant solution was accerelated according to increasing quantities of reducing metal. However, the excess of reducing metal reduced the grade of cement copper. 3)Among the comparative experiments of copper recovery at each reaction temperature of $10^{\circ}C$, $20^{\circ}C$, and $30^{\circ}C$, the recovery rate of copper at $30^{\circ}C$from the pregnant solution was highest. 4)Direct cementation method on iron-containing metal was an excellent method for the recovery of cement copper in bacterial leaching.

• Proceedings of the Korean Geotechical Society Conference
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• 1993.06a
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• pp.1-14
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• 1993

Ground reinforcements is the essential method to prevent the liquefaction of loose sand deposit, However, in the construction of the life lines, it is impossible to treat the whole loose deposit against liquefaction. As an countmeasure for the life lines against the liquefaction, a monitorning system can be considered for an immediate judgement of the liquefaction occurrence during an earthquake. Through shaking table tests on model grounds, pore presure developments were investigated in terms of the surface spectral velocity, which was verified as a tool for the immediate judgement of the liquefaction occurrence.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2003.03a
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• pp.193-199
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• 2003

The most cultural heritages are composed of piled multi-block systems which are vulnerable to earthquakes. The stone of low height tends to slide when the excitation such as earthquake is applied and this sliding motion has effects on the whole response of the structure. In this study, analytical method of sliding motion of the piled multi-block systems considering horizontal rotation is developed and compared with shaking table test results. It is shown that the nonlinear analysis of sliding motion of multi-block system leads to satisfactory results.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2000.04a
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• pp.112-119
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• 2000

the shaking table tests for 5 different model sections are performed to investigate the behaviors of quay walls during earthquakes and to evaluate the seismic performance of quay walls with countermeasures. 5 different model sections describe the cases of dense soil and loose soil in the foundation repectively the case to which gravel backfill was applied and the cases to which light material replacement method and sand compction pile method was applied repectively for sesmic countermeasure methods. Pore water pressures accelerations and deformations in quay walls and grounds are analyzed. As a result the softening of foundation and backfill soils have much influence on the behaviors of quay walls. Also light material replacement method and sand compaction pile method are effective in improving the seismic performance of quay walls.

• KSBB Journal
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• v.8 no.4
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• pp.364-369
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• 1993

The biodegradability of some anionic surfactants were investigated using biological oxygen consumption measurement at different temperatures. As test surfactants, soap, alkyl sulfate (AS), alpha olefin sulfonate (AOS), alkyl polyoxyethylene sulfate (AES), linear alkylbezene sulfonate(LAS), microbial surfactants such as sophorose lipid (sopholipid) and spiculisporic acid (S-acid), were used. The test solution were incubated at $5^{\circ}C$, $18^{\circ}C$ and $32^{\circ}C$, respectively. The comparative rates of biodegradation were in accordance with the results obtained from the surface tension measurement and methylene blue method. The results of comparative blodegradabilities of the surfactants were as follows; soap, AS>AES>AOS>LAS at $18^{\circ}C$ and $32^{\circ}C$. However, at$ 5^{\circ}C$, the biodegradation rate of soap was better than other surfactants. Considering the actual environment of the river, it was concluded that the biological oxygen consumption rate method at lower temperature was more practical than the current method such as methylene blue assay with adapted shaking flask culture at $25^{\circ}C$

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2003.10a
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• pp.465-472
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• 2003

In this paper, the displacement-based seismic design approaches are evaluated utilizing shaking-table test data of a 1:3 scaled reinforced concrete (RC) bearing wall structure Provided by IAEA. The maximum responses of the structure are estimated using the two prominent displacement-based approaches, i.e., the capacity spectrum method and the displacement coefficient method, and compared with the measured responses. For comparison purpose, linear and nonlinear time history analyses and response spectrum analysis are also performed. The results indicate that the capacity spectrum method underestimates the response of the structure In inelastic range while the displacement coefficient method yields reasonable values in general.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.5
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• pp.715-722
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• 2013

Gas insulated switchgear is large-sized electric equipment for providing a reliable supply of electric power. Recently, seismic tests of electric equipment using a shaking table have been mandated because seismic performance has become an increasingly important issue. However, basic analysis methods continue to be used because some electric equipment is too large for shaking table facilities. Thus, a reliable analysis method should be developed for large-scale electric equipment. This study aims to evaluate the seismic qualification of a 245kV GIS in accordance with IEEE-693 and to validate the analysis method by comparing it with test results. Both the test and the analysis showed that the 245kV GIS has proper seismic safety. Furthermore, the differences between the analysis and the test results are less than 10% for an accurately given mass, stiffness, and input acceleration. It is expected that this study can be used for the seismic qualification of large-scale electrical structures.