• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.6
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• pp.14-20
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• 2015

A high-speed reduction transfer case is usually employed by an excavator, wheel loader, or bulldozer. When powerful torque is required in the case of climbing steep roads or towing heavy equipment, the high-speed reduction mode of the gearbox is used. Generally, a transfer case using a spur gear type with a speed reduction system has a speed reduction ratio of 1 to 1 or 2 to 1. However, the structure of a transfer case achieved at a high speed of 1 to 1 and a low speed of 4.5 or under 5.5 to 1 with the speed reduction by use of a planetary gear type with a speed reduction system was proposed in this study. By employing a planetary gear type with a speed reduction system, the compact structure of the transfer case was achieved, and the impact or the partial defect of gear teeth was eliminated.

• Journal of Chest Surgery
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• v.18 no.2
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• pp.273-278
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• 1985

The case of a patient with abnormal position of the atrial septum resulting in a left atrium with two atrioventricular valves and a disconnected right atrium is presented with review of related articles. Anatomic details showed atrial situs solitus and a left sided cardiac apex. The right atrium received both venae cavae and a coronary sinus. No AV valve was found in the right atrium, and the floor of this chamber was placed above the posterior wall of right ventricular chamber. The atrial septum with secundum ASD was displaced to right anteriorly at its lower portion and inserted to right of tricuspid annulus. The tricuspid and mitral valve configuration was that of so-called partial ECD, i.e. mitral cleft with large anterior mitral leaflets. The ventricular septum was intact and both ventricular chambers were equally well developed with normal relationships. Surgical repair of this anomaly was performed by resecting the abnormally positioned lower part of the atrial septum, repairing the cleft of the anterior mitral leaflet, and septating the atrium for diverting the systemic and pulmonary venous blood to RV and LV, respectively.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.4
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• pp.788-794
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• 2009

To assess the condition of stator insulation, nondestructive tests were performed on twenty five coil groups and twenty six motors. The stator windings has nominal ratings of 6.6kV and are classified into five coil groups ;one group with healthy insulation and four groups with four different types of artificial defects. After completing nondestructive tests, the AC voltage applied to the stator windings was gradually increasing until insulation failure in order to obtain the breakdown voltage. No.1, No.2 and No.6 of 6.6kV motors failed near rated voltage of 14kV, 8.7kV and 14kV, respectively. The breakdown voltage of three motors was lower that expected for good quality coils(14.2kV) in 6.6kV motors. No.3 and No.6 of 4.16kV motors failed near rated voltage of 5.6kV and 4.2kV, respectively. Almost all of failures were located in a line-end coil at the exit from the core slot. The breakdown voltages and the types of defects showed strong relation to the stator insulation tests such as in the case of AC current, dissipation factor(tan${\delta}$) and partial discharge magnitude.

• Archives of Plastic Surgery
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• v.32 no.4
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• pp.441-446
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• 2005

Sole reconstruction should consider both functional and aesthetic aspects; durable weight bearing surface, adequate contour for normal footwear, protective sensation and solid anchoring to deep tissue to resist shearing. The anterolateral thigh perforator free flap has such favorable characteristics as long pedicle, reliable perforators and minimal donor site morbidity. This flap can be safely thinned to 3-4 mm. It can also be elevated with sufficient bulk with muscles like vastus lateralis for complex defect. Between June 2002 and December 2004, 48 cases of sole reconstruction were performed with anterolateral thigh perforator free flaps. Follow up period ranged from 4 to 34 months with a mean of 14.7 months and with exception of one case, all flaps survived. One case of total flap loss was noted due to infection in a patient who was administered lifetime immunosuppressant. Partial necroses developed in three cases but were treated conservatively. Satisfactory aesthetic and functional results were achieved and acceptable gait recovery was noted. Seventy-eight percent of the patients regained protective sensation by 6 months and earlier sensory recovery was noted in sensate flap group. The authors also present a standardized protocol for preoperative patient evaluation and postoperative management and rehabilitation.

• International Journal of Aeronautical and Space Sciences
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• v.12 no.1
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• pp.1-15
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• 2011

This paper reviews most of the research done in the field of tensile buckling characteristics pertaining to aerospace structural elements with special attention to local buckling and parametric excitation due to periodic loading on plate and shell elements. The concepts of buckling in aerospace structures appear as the result of the application of a global compressive applied load or shear load. A less usual situation is the case, in which a global tensile stress creates buckling instability and the formation of complex spatial buckling pattern. In contrast to the case of a pure compression or shear load, here the applied macroscopic load has no compressive component and is thus globally stabilizing. The instability stems from a local compressive stress induced by the presence of a defect, such as a crack or a hole, due to partial or non-uniform applied load at the far end. This is referred to as tensile buckling. This paper discusses all aspects of tensile buckling, theoretical and experimental. Its far reaching applications causing local instability in aerospace structural components are discussed. The important effects on dynamic stability behaviour under locally induced periodic compression have been identified and influences of various parameters are discussed. Experimental results on simple and combination resonance characteristics on plate structures due to tensile buckling effects are elaborated.

• Journal of Korean Neurosurgical Society
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• v.45 no.1
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• pp.43-45
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• 2009

A 75-year-old female presented with subarachnoid hemorrhage. Angiography revealed a partial duplication (fenestration) in the proximal $A_1$ segment and a ruptured aneurysm at the distal end of $A_1$ fenestration. This congenital anomaly accompanying an aneurysm was associated with duplicated ipsilateral middle cerebral artery (MCA). Congenital defect of the arterial wall and hemodynamic factors at the fenestrated $A_1$ are considered to play a significant role in the development of this aneurysm. The present case is peculiar because not only the ruptured $A_1$ aneurysm was related with the anterior and middle cerebral artery duplication but also the location of $A_1$ fenestration and the origin of $A_1$ aneurysm in a fenestration are quite unusual.

• Archives of Pharmacal Research
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• v.28 no.6
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• pp.667-674
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• 2005

The leaves of Persimmon (Diospyros kaki L.) has long been used for tea in Korea since it was thought to be effective against hypertension. An anticoagulant fraction was purified through gel filtration G-100, hydrophobic, gel filtration G-150, and FPLC, Phenyl superpose column chromatographies. The purified fraction was homogenous and its Mr was estimated 10,000 Da by gel filtration and SDS-PAGE. The purified fraction was sensitive to treatment of subtilisin B, but not to heat and its activity was not changed after periodate oxidation, indicating that the activity was not due to carbohydrates. It delayed thrombin time (TT), activated partial thromboplastin time (APTT), and prothrombin time (PT) using human plasma. TT was more sensitive than APTT and PT, suggesting that the anticoagulant activity may be caused by a degradation or a defect of fibrin or thrombin. It did not cause the hydrolysis of fibrin after incubation. However, it inhibited thrombin-catalyzed fibrin formation with a competitive inhibition pattern. These results indicate that it may be an antithrombotic agent and that it is bound to fibrinogen binding sites of thrombin.

• International Journal of Vascular Biomedical Engineering
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• v.4 no.1
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• pp.9-16
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• 2006

In this article we introduce computer models that have been developed in the past to determine the concentration of metabolic gases, the oxygen and carbon dioxide, along the pulmonary circulation. The terminal concentration of these gases in the arterial blood is related with the total change of the partial pressure of the same gases in the alveoli for the time beginning with inspiration and ending with expiration. It is affected not only by the ventilation-perfusion ratio and the gas diffusion capacity of the lung membrane but also by the pulmonary defect such as shunt, dead space, diffusion impairment and ventilation-perfusion mismatch. Some pathological pulmonary symptoms such as ARDS and CDPD can be understood through the mathematical models of these pulmonary dysfunctions. Quantitative study on the blood oxygenation process using various computer models is therefore of foremost importance in order to monitor not only the pulmonary health but also the cardiac output and cell metabolism. Reviewed in this paper include the basic and advanced methods that enable numerical study on the gas exchange and on the arterial oxygenation process, which might depend on the various heart and lung physiological conditions listed above.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.10
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• pp.895-900
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• 2007

Partial discharge(PD) test can be performed either when the rotating machine is not operating(off-line) or during normal machine operation(on-line). This paper presents an on-line and off-line PD test on a large hydro-generator and induction motor using the same PD acquisition system(PDAS) and ceramic coupler(CC) sensor. PD signal characteristics of CC sensor proved similar with that of epoxy mica coupler(EMC) sensor as a results of PD test for simulated defect winding and frequency response test. A comparison of on-line and off-line PD test for PD characteristic parameters-phase resolved PD(PRPD), maximum PD value(Qmax) and PD occurrence energy(POE)-indicated that on-line PD test could reliably and effectively diagnose insulation conditions which were verified by off-line PD test.

• Journal of Dental Rehabilitation and Applied Science
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• v.23 no.2
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• pp.145-155
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• 2007

The advent of osseointegration and advances in biomaterials and techniques have contributed to increased application of dental implants in the restoration of maxillary partial edentulous patients. Often, in these patients, soft and hard tissue defects result from a variety of causes, such as infection, trauma, and tooth loss. These create an anatomically less favorable foundation for ideal implant placement. Reconstruction of the atrophic maxillary alveolar bone through a variety of regenerative surgical procedures has become predictable; it may be necessary prior to implant placement or simultaneously at the time of implant surgery to provide a restoration with a good long-term prognosis. Regenerative procedures are used for horizontal and vertical ridge augmentation. Many different techniques exist for effective bone augmentation. The approach is largely dependent on the extent of the defect and specific procedures to be performed for the implant reconstruction. It is most appropriate to use an evidenced-based approach when a treatment plan is being developed for bone augmentation cases. The cases presented in this article clinically demonstrate the efficacy of using a autogenous block graft, guided bone regeneration, ridge split, immediated implant placement technique on the atrophic maxillary area.