• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.228-231
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• 2002

Itaconic acid has been produced during the cutivation of Aspergillus terreus DSMZ 5770 by using several starchs as carbon sources. The starchs were pretreated by partial hydrolysis with some acids at various pH conditions. The highest yield for the production of itaconic acid has been found when rice starch was pretreated by sulfonic acid at pH 2.5 and utilized for the cultivation. Using the results from shaker fermentation A. terreus has been cultivated in 2.5 L bioreactor for the production of itaconic acid and its on-line monitoring.

• Bulletin of the Korean Chemical Society
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• v.23 no.3
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• pp.374-380
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• 2002

Several compounds of 3,9-dialkylxanthines were prepared from 1-methyl-6-chlorouracil via nucleophillic reactions with different aliphatic amines, followed by nitrosation, reduction, formaylation and finally dehydrocyclization. On the other hands, a series of 8-aryl-3,9-dimethylxanthines were synthesized by dehydrocyclization of 5-arylamido-1-methyl-6-methylaminouracils either by fussion or oxidation of 5-arylidine-amino-1-methyl-6-methylaminouracils using sodium periodate. Phosphoryl chloride was found to be uneffective reagent for dehydrocyclization that, gave another products from 1,3-oxazolo[5,4-d] pyrimidines.

• Proceedings of the Optical Society of Korea Conference
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• 2003.02a
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• pp.322-323
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• 2003

Silicon substrate was fabricated by bulk silicon micromachining and it's structure is based on a proof mass suspended by two beam. To monitor the acceleration, dynamic excitation of accelerometer was performed using a shaker. The attached FFPI and suspension beam are bent because support beam move with variation of the proof mass. Thus phase difference detected by the acceleration change. So we can know that resonance frequency of fabricated accelerometer is about 557 Hz and dynamic range was measured from 0 g to 2 g.

• International Journal of Control, Automation, and Systems
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• v.6 no.2
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• pp.180-185
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• 2008

A new method for relative error continuous and discrete time model order reduction is proposed. The reduction technique is based on two recently developed methods, namely frequency domain balanced truncation within a frequency bound and inner-outer factorization techniques. The proposed method is of interest for practical model order reduction because in this context it shows to keep the accuracy of the approximation as high as possible without sacrificing the computational efficiency. Numerical results show the accuracy and efficiency enhancement of the method.

• Korean Chemical Engineering Research
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• v.53 no.6
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• pp.703-708
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• 2015

In order to improve the dispersity of nanofiller, polyurethane (PU) nanocomposites were manufactured via poly(propylene gylcol) (PPG) dispersion with MWCNTs prepared by using a ball mill shaker. MWCNTs could be functionalized by treating with the hydrogen peroxide ($H_2O_2$). Tensile strengths and elongations at break of $PU/H_2O_2$ treated MWCNTs nanocomposites were enhanced compared to those of the PU/pristine MWCNTs nanocomposites. The good dispersion of MWCNTs shown in SEM images was obtained by the functionalization of MWCNTs surface. PU/carbon black (CB) composites showed no significant change in the tensile properties. The tensile properties of PU nanocomposites containing pristine MWCNTs or $H_2O_2$ treated MWCNTs were enhanced with increasing dispersion time. As a result, it was certified that the enhanced dispersity of nanofiller brought the improvement of the tensile properties of the MWCNTs based PU nanocomposites.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.110-110
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• 2017

Stomata are the main gateways for water and air transport between leaves and the environment. Inward-rectifying potassium channels regulate photo-induced stomatal opening. Rice contains three inward rectifying shaker-like potassium channel proteins, OsKAT1, OsKAT2 and OsKAT3. Among these, only OsKAT2 is specifically expressed in guard cells. Here, we investigated the functions of OsKAT2 in stomatal regulation using three dominant negative mutant proteins, OsKAT2(T235R), OsKAT2(T285A) and OsKAT2(T285D), which are altered in amino acids in the channel pore and at a phosphorylation site. Yeast complementation and patch clamp assays showed that all three mutant proteins lost channel activity. However, among plants overexpressing these mutant proteins, only plants overexpressing OsKAT2(T235R) showed significantly less water loss than the control. Moreover, overexpression of this mutant protein led to delayed photo-induced stomatal opening and increased drought tolerance. Our results indicate that OsKAT2 is an inward-rectifying shaker-like potassium channel that mainly functions in stomatal opening. Interestingly, overexpression of OsKAT2(T235R) did not cause serious defects in growth or yield in rice, suggesting that OsKAT2 is a potential target for engineering plants with improved drought tolerance without yield penalty.

• Journal of the Korean Society for Nondestructive Testing
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• v.35 no.4
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• pp.245-250
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• 2015

To verify the possibility of generating rattling noise from a motor on caliper brake system, a test was conducted using a caliper excited with vibrations similar to that in a vehicle running on actual roads; this test was conducted using a quiet shaker installed in an anechoic room. After several hours of external excitation, the test assembly was loosened, and the frequency of rattling noise generation increased. A microphone was used to record the generated noise. The measured signals were analyzed by conventional spectrum analysis. Since the noise is generated as an impact response, the advantages of employing Prony analysis was discussed, and the results were compared to those obtained using conventional fast Fourier transforms. The accuracy of Prony analysis was through endurance tests on different brake systems.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.11
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• pp.1113-1121
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• 2015

In this study, we have focused on the design of a controller and an operating program for the operation of the hydraulic actuators used in a shaker. To control the motion of the shaker accurately, the position of each hydraulic cylinder should be controlled precisely even under an uncertain environment. For this purpose, we have suggested a control algorithm using an FRF (frequency response function) based control which senses the behavior of the actuator in advance, calculates a transfer function through the system identification method, and provides the final control input. The experimental results on the performance of this system were compared with that of a simple PID control algorithm.

• Journal of The Korean Society of Integrative Medicine
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• v.7 no.1
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• pp.27-36
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• 2019

Purpose : The purpose of this study figures out how the biofeedback exercise combined with a Shaker exercise and a jaw-opening exercise affects the suprahyoid muscle activation of stroke with a swallowing disorder. Methods : The study period was from June, 2018 to September, 2018, to 45 patients who were suitable for selection criteria. Participants were divided into three groups: a visuoauditory biofeedback group (VABG), and a visual biofeedback group (VBG), and a self-exercise group (SG). The three groups were divided into the Shaker exercise and the jaw-opening exercise, and the biofeedback training by themselves. Three groups performed an intervention three times a day, five times a week, and four weeks long. Also, suprahyoid muscle activity was measured with a pre-test, a post-test and a follow-up test. Results : To know the suprahyoid muscle activity after the intervention, there were statistically significant differences between the pre-test and the post-intervention (p< .01). All three groups showed the improvement with the mean comparing followed by VABG, VBG and SG. Comparing between the post- test and the follow-up test, all three groups showed the reduction of suprahyoid muscle activity with the mean comparing, followed VABG, VBG and SG. Conclusion : It found that it was more effective when providing a double-sensory biofeedback than when training with a single-sensory biofeedback. Therefore, it is necessary to provide a multi-sensory input when applying the biofeedback in rehabilitation of the swallowing disorder.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2004.04a
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• pp.57-64
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• 2004

Stay cables, such as are used in cable-stayed bridges, are prone to vibration due to their low inherent damping characteristics. Several methods have been proposed and implemented to mitigate this problem, though each has its limitations. Recently some studies have shown that semiactive dampers can potentially achieve performance levels nearly the same as comparable active devices with few of the detractions. This paper presents the results of a study to evaluate the performance of semiactive dampers for mitigating the vibration of stay cables. Moreover, a number of recently proposed semiactive control algorithms are formulated for use with shear mode MR damper to compare the efficiency of each algorithm through numerical simulation. Numerical simulation considers a stay cable excited by shaker and controlled by shear mode MR dampers. In simulation, the response with a semiactive damper is found to be dramatically reduced compared to the uncontrolled case. Furthermore, it is verified that the algorithm based on Lyapunov control theory is very efficient in mitigating the cable vibration.