• Microbiology and Biotechnology Letters
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• v.21 no.2
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• pp.157-162
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• 1993

Raw starch can be effectively saccharified in an enzyme reaction system containing sttrition-milling media. In order to develop an effcient attrition-coupled bioreactor(bioattritor), a rotating drum type bioattitor was construced, and its optimal operation conditions and power consumptions were evaluated. The optimal conditions for 3l bioattritor were 4 baffled, baffle size of 1:0.05 (the ratio of drum diameter to baffle), drum rotation speed of 100 rpm, and 1.33g of 3 mm glass bead/g of raw corn starch.

• Journal of Magnetics
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• v.3 no.3
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• pp.69-73
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• 1998

A drum type magnetic separator was designed and optimized by computer simulation. The separator consisted of rotating outer shell of drum, magnetic flux generator drum which was assembled with numbers of disk type magnet holders, and drum axis around which the magnet holders were fixed. NdFeB magnet blocks were inserted into the disks, and the disks were assembled layer by layer along the drum axis. Magnetic circuits of the separator were simulated on the basis of highest magnetic strength, least cost, and high yield of separation by using a Vector Field S/W employing the Opera-2D program. The separator proved a separation yield of 95% in removing fine iron-base particles, and installed at Hot Rolling Mill of Pohang Iron & Steel Co. In Korea.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.3
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• pp.173-180
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• 2001

In the case of axisymmetric thermal analysis of drum brakes, the distribution of frictional heat produced on the interface and temperature difference between mating frictional faces are very interesting problems to computational researchers. In the first part, the influence of the s-cam load angles and elastic modulus of the pad on the contact pressure distribution between pad and drum was checked by a three dimensional model. In the second part heat conduction from the interface to the pad and the drum was modeled by using a thin interface element, so artificial division of the generated frictional heat between pad and drum is not necessary. Temperature difference between mating frictional faces is successfully modeled by using the interface element. The influence of some parameters on the thermal distribution is checked. The analysis was performed by ABAQUS/Standard code.

• Journal of the Korea Institute of Military Science and Technology
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• v.5 no.1
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• pp.45-58
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• 2002

In this paper, we designed the circuit of drive control for towing winch. It is composed of reference voltage circuit for driving voltage reference, low pass filter circuit for noise reduction, dead zone circuit for initial transient input, and driving circuit for drum direction/velocity control. Also it is realized a drive control circuit for towing winch drum in accordance with PWM(pulse width modulation) method to suit it's purpose of a large capacity driving system. The performance of the designed circuit is analyzed by experiments and the appliablity for driving the towing winch drum satisfactorily is evaluated through a various testing.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.919-923
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• 2012

본 연구에서는 K-water에서 자체 개발한 물리적 기반의 격자단위 강우-유출모형(K-DRUM ; K-water Distributed rainfall RUnoff Model)을 일 단위 장기유출 분석에 활용하기 위해서 유역의 증발산량 산정 및 융 적설 등을 모의할 수 있는 기능을 추가로 개발하였고, 재현성 분석을 위하여 남강댐 유역을 대상으로 장기유출모의를 수행하였다. 모의결과 단기 홍수사상의 경우 유출량에서 증발산 효과가 크지 않지만 연간 전체 유출량을 비교할 경우에는 상당한 차이가 발생하는 것을 확인할 수 있었다. 결과적으로 본 연구를 통해 개선된 K-DRUM 모형은 단기 홍수유출 뿐만 아니라 융 적설을 고려한 장기유출 분석에도 활용이 가능할 것으로 판단된다.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.9
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• pp.111-116
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• 1998

The squeal of drum brakes was investigated numerically and experimentally. Modal testings were performed for shoes, drums, backing plates and their assemblies. In order to predict the squeal phenomena, stability analysis was performed based on a simplified self-excited vibration model. Based on modal testings, the dynamic properties of the brake elements and the parameters used in this analysis were determined. The geometries of shoes and drums were also considered. The result shows that the modification methods of the shoe and the drum design are feasible for noise reduction.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.4_1
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• pp.545-551
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• 2023

In this paper, a robot automation methodology for chemical drum assembly in semiconductor industries are presented. Robot automation is essential to resolve safety issues in which operators are directly or indirectly exposed to chemicals or fumes in assembling dispense heads on chemical drums. However, the chemical drum assembling process involves complex and difficult tasks, such as mating male/female keycodes and fastening screws with large-diameter, which may be very difficult to be performed by a single-arm robot with a commercial rigid F/T sensor. In order to solve the problems, a method for assembling a chemical drum using dual-arm collaborative robot system, compliance F/T sensor, robot vision and gripper is presented.

• Journal of the Korean Society for Precision Engineering
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• v.10 no.2
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• pp.22-29
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• 1993

A remote control system was developed in order to operate by push-buttons the conventional drum and chute components, which have been operated manually, in a concrete mixer-truck. As actuators, a hydraulic power unit was used for chute operations: two DC motors for drum operations. The devised drum controller consisted of three electric circuits : an analog proportional-integral control circuit, a drum acceleration circuit, and an emergency stop circuit. The remote control system was installed to be tested experimentally and then was evaluated to work successfully with a desirable accuracy.

• Environmental Engineering Research
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• v.18 no.3
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• pp.177-189
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• 2013

Studies were carried out on the speciation of heavy metals (Zn, Cu, Mn, Fe, Ni, Pb, Cd, and Cr) during rotary drum composting of water hyacinth (Eichhornia crassipes) for a period of 20 days. Five different proportions of cattle manure, water hyacinth and sawdust were prepared for composting. This study concluded that, rotary drum was very efficient for the degradation of organic matter as well as for the reduction of mobility and bioavailability of heavy metals during water hyacinth composting. The results from the sequential extraction procedure of heavy metals shows that rotary drum composting changed the distribution of five fractions of Zn, Cu, Mn, Fe, Ni, Pb, Cd, and Cr. The highest reduction in the bioavailability factors of Pb and Cd was observed during the process. The total concentration of Cu, Cr, and Cd was very low compared to the other metals (Zn, Mn, Fe, Ni, and Pb); however, the percentage of exchangeable and carbonate fractions of these metals was similar to other metals. These results confirmed that the bioavailability of metals does not depend on the total concentration of metals. From this study, it can be concluded that the addition of an appropriate proportion of cattle manure significantly reduced the mobile and easily available fractions (exchangeable and carbonate fractions) during water hyacinth composting in rotary drum.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.05a
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• pp.739-742
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• 2000

From the experimental study of W-EDM for alloyed steel, the characteristics such as Hand Drum Form and surface roughness have been observed and evaluated for various conditions. In square hole, the increase of If as to made condition the calculate high value of surface roughness. Also compare dimensionless square hole with circle hole' graph. In circle hole, if a value of surface roughness IP 6 in a side of circle it show a 0.4${\mu}{\textrm}{m}$ and in IP 8, 0.6${\mu}{\textrm}{m}$, in IP 10, 0.7${\mu}{\textrm}{m}$, in IP 12. 0.8${\mu}{\textrm}{m}$ higher than before. This figure show the surface roughness is higher than before, because a table move in either X-axis or Y-axis in square hole, on the contrary, in circle there table move in X-axis and Y-axis at the same time. hand drum form getting small when wire tension increase 1000gf to 1500gf, at the same working conditions. the smaller of off time, the mailer of hand drum form in same condition and same wire tension. but if you compare square hole with circle hole' graph hand drum form displayed in maintained term of working condision, on the contrary, in case of square hole variation of hand drum form is more increase than a grow of IP