• Journal of Power System Engineering
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• v.5 no.3
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• pp.56-63
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• 2001

A slitter is a sort of machinery to cut sheet materials in rolls continuously in the longitudinal direction. Recently slitter line users have requiring higher quality and precision in products in addition to high productivity. A finite element analysis has been performed to investigate the effect of processing factors on shear planes in the slitting of Shrinkage Band(S,K.B.). For the analysis, Hot-dip 55% aluminum-zinc alloy-coated steel sheets and coils(SAZCC) is selected as a material. The results obtained are that deformation was concentrated along the very narrow zone and the maximum slitting load decreases by increasing the knife clearance. Also effective strain decreases according to the clearance increases.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.6
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• pp.440-447
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• 2001

This study investigate experimentally the effect of in height, thickness, and clearance on the boiling heat transfer. The heat surfaces having copper fin array is tested for pool boiling. The gas-liquid exchange interference is investigated based on fin array clearance. These test results can be applied to the design of tube bundle system. The fin height of 2 mm is found to be effective. Effects of heat transfer promotion reaches the highest level when the fin clearance is 0.5mm. Also, heat flux is increased when the fin thickness is smaller. But0.2 mm fin thickness is highly recommended.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.12
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• pp.6060-6065
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• 2013

Minimizing the height of the die roll is very important for maximizing the size of effective shear planes. In this study, the die roll change was investigated for the change in the amounts and clearance of the V-ring indentation. Shear analysis and experiments were conducted with the V-ring distance fixed to 2mm. Fine blanking die was applied to the die insert with different clearances. Several specimens were analyzed about the height of the die roll. As a result, the pressure of V-ring effectively inhibited the flow of materials. And the height of the die roll was lowest when the clearance between the die and punch was 1% of the material thickness.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.28 no.4
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• pp.196-207
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• 2015

Purpose : To observe effects of Korean Medicine treatment for genital warts.Methods : In a single private clinic from February 2014 to February 2015, we did retrospective chart review for 326 patients with genital warts who had been treated by Korean Medicine. Korean Medicine treatment included herbal treatment and herbal ointment.Results : A total of 326 patients were enrolled in this study: 62.7%(n=219) male, 32.8%(n=107) female. In the type of diagnosis, new diagnosis was 45.4%(n=148) and recurrent disease was 54.6%(n=178). Complete clearance was achieved 63.2%(n=206) and treatment period was 3.5 months(range:1-9). Partial clearance-good was 15%(n=49), partial clearance-poor was 4.9%(n=16), non response was 16.9%(n=55) and the average treatment period was 4.3 months(range:1-14). In complete clearance group, female and the prevalence of less than 1 year were statistically significant(p<0.05). There was no recurrence of genital warts after TKM treatment during follow-up period(4-13months).Conclusion : This study suggest that Korean Medicine may be an effective treatment for genital warts.

• The Journal of Internal Korean Medicine
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• v.41 no.3
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• pp.502-507
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• 2020

This study aimed to investigate the effect of Hwanglyeonhaedok-tang on the clearance of vancomycin-resistant Enterococcus (VRE) colonization in a patient with traumatic subarachnoid hemorrhage and subdural hematoma. A 73-year-old man who was diagnosed with traumatic subarachnoid hemorrhage and subdural hematoma with isolation of VRE colonization was administered Hwanglyeonhaedok-tang and followed up with a rectal swab VRE culture every week. After treatment with Hwanglyeonhaedok-tang, VRE colonization was no longer detected. This case report proved that Hwanglyeonhaedok-tang could be an effective treatment for clearance of VRE colonization in a patient with traumatic subarachnoid hemorrhage and subdural hematoma.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1997.04a
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• pp.111-121
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• 1997

The stability of a rotor-bearing system supported by swirl-controlled hybrid journal bearing with pair-type angled injection orifices is investigated for improvement of the whirl frequency ratio by allowing effective control of the tangential flow inside the bearing clearance, i.e., by achieving more freedom in controlling strength and direction of the supply tangential flow inside the bearing clearance. It is suggested that the system instability can be improved through the change of bearing dynamic characteristic parameters with the swirl control. The orifice diameter d$_0$ and recess injection angle $\alpha$ along with combinations of swirl/anti-swirl supply pressures and directions (3.0-3.0MPa, 4.0-2.0MPa, 2.0-4.0MPa) are selected for design parameters for swirl-controlled effective factors dependent on journal speeds (3000, 9000, 15000, 21000 rpm). It has been found that the orifice diameter do shows strong effects on effective maneuverability of direct-stiffness and direct damping values, while recess injection angle $\alpha$ results in substantial magnitude and direction of cross-stiffness. Specifically, recess injection parameters which are functions of angle of orifice feeding flow and recess dimensions showed very feasible effect on the stability of swirl-controlled rotor-bearing system.

• Tribology and Lubricants
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• v.13 no.3
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• pp.63-72
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• 1997

The stability of a rotor-bearing system supported by swirl-controlled hybrid journal bearing with pair-type angled injection orifices is investigated for improvement of the whirl frequency ratio by allowing effective control of the tangential flow inside the bearing clearance, i.e., by achieving more freedom in controlling strength and direction of the supply tangential flow inside the bearing clearance. It is suggested that the system instability can be improved through the change of bearing dynamic characteristic parameters with the swirl control. The orifice diameter $d_0$ and recess injection angle $\alpha$ along with combinations of swirl/anti-swirl supply pressures and directions (3.0~3.0 MPa, 4.0~2.0 MPa, 2.0~4.0 MPa) are selected for design parameters for swirl-controlled effective factors dependent on journal speeds (3000, 9000, 15000, 21000 rpm). It has been found that the orifice diameter $d_0$ shows strong effects on effective maneuverability of direct-stiffness and direct damping values, while recess injection angle $\alpha$ results in substantial effects on the magnitude and direction of cross-stiffness. Specifically, recess injection parameters which are functions of angle of orifice feeding flow and recess dimensions showed very feasible effect on the stability control of swirl-controlled rotor-bearing system.

• Journal of Korean Institute of Industrial Engineers
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• v.37 no.2
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• pp.153-162
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• 2011

The demands of complicated data communications have issued a new challenge to port logistics systems. Customers expect ports to handle their generated administrative data while a vessel is docked in a port. One port logistics system, known as the Vessel Clearance Process (VCP), manages large numbers of documents related to port of entry. In the VCP, information flows through many organizations such as the port authority, shipping agents, marine offices, immigration offices, and others. Therefore, for effective management of the Business Process (BP) of the VCP, a standardized method of BP modeling is essential, especially in heterogeneous system environments. In a port, according to port policy, terms and data are sued that are similar to but different from those of other logistics partners, which hinders standardized modeling of the BP. In order to avoid tedious and time-consuming document customization work, more convenient modeling of BP for VCP is essential. This paper proposes an ontology-based process similarity measurement to assist designer for process modeling in port domain, especially VCP. We expect that this methodology will use convenient and quick modeling of port business processes.

• International Journal of Fluid Machinery and Systems
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• v.4 no.2
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• pp.217-222
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• 2011

The rotordynamic fluid forces acting on a closed type impeller in whirling motion were measured and the influence of the clearance geometry on the stability of the impeller was examined. At small positive whirling speed, the rotordynamic forces acted as destabilizing forces for all casings. A small clearance between the shroud of the impeller and the casing caused large fluid force, but did not change the destabilizing region. Radial grooves in the clearance were effective for reducing the fluid forces and destabilizing region due to the reduction of the circumferential velocity without the deterioration of the pump performance. A rotating phenomenon like a rotating stall of the impeller occurred at low flow rate and the resonance between it and the whirling motion led to a sudden increase in force at the whirling speed ratio of 0.7.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.12
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• pp.1327-1333
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• 2013

Air bearings are widely used in precision stages because of low friction and high motion accuracy, however, they suffer from low stiffness in comparison with rolling bearings or hydrostatic bearings. So, several preloading methods using weight, magnet and vacuum force, and opposing pads have been used to increase the stiffness of the air bearings. In this paper, pressure distributions of the vacuum preloaded porous air bearings are calculated using the proposed method. And then, the load capacity and stiffness are analyzed. For the vacuum preloaded air bearings, the stiffness is increased owing to reduced bearing clearance by vacuum force. The simulation results indicate that variation of vacuum pressure with clearance in the vacuum pocket gives rise to low stiffness, so the vacuum pocket should be designed for pressure to be constantly maintained regardless of the bearing clearance by means of large effective pumping speed.