• Journal of Power Electronics
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• v.9 no.5
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• pp.800-808
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• 2009

This paper presents a practical method of pressure control for a hydraulic oil-pump system using an SR (Switched Reluctance) drive. For a 6Mpa grade hydraulic oil-pump, a 2.6kW SR drive is developed. In order to get high performance pressure dynamics in actual applications, a data based PID control scheme is proposed. The look-up table from a pre-measured data base produces an approximate current reference based on motor speed and oil-pressure. A PID controller can compensate for the pressure error. With the combination of the two references, the proposed control scheme can achieve fast dynamics and stable operation. Furthermore, a suitable current controller considering the nonlinear characteristics of an SRM (Switched Reluctance Motor) and practical test methods for data measuring are presented. The proposed control scheme is verified by experimental tests.

• 유체기계공업학회:학술대회논문집
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• 2005.12a
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• pp.509-514
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• 2005

Main coolant pump (MCP) is a canned-motor-type axial pump to circulate the primary coolant between nuclear fuel rods and steam generators in an integral type reactor. The reactor is designed to operate under condition of 310 oC and 14.7 MPa. Thus MCP has to be tested under same operating condition as reactor design condition in order to verify its performance and safety. In present work, a test loop to simulate real operating situation of the reactor has been designed and constructed to test MCP. And then, as a part of qualification test, canned motor functional test and pump hydraulic performance test have been carried out upon a prototype MCP. Canned motor efficiency and pump hydraulic characteristics including homologous curves and NPSH curves were obtained from the qualification test.

• Proceedings of the KSR Conference
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• 1999.11a
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• pp.360-367
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• 1999

An inverter-driven induction motor is used as the traction motor for a high speed drive system that required safety, reliabillity, performance, compact size owing to the space and weight alloted for attaching to train, etc. particularly it is possible to happen the saturation effects of flux density at constant voltage-frequency region and then increase very higher than the at lowed capacity of no-load current and temperature in any case. therefore the optimum design of core, optimum voltage-frequency ratio, adoption of high grade magnetic core have been developed and researched for preventing these problems. this paper show the saturation effects of traction rotor by measuring the induced voltage of search coil at stator teeth and presents optimum voltage-frequency ratio as well as optimum core design through the comparison with efficiency, power factor, load current and no-load current for korea high speed train.

• Journal of Acupuncture Research
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• v.31 no.4
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• pp.155-162
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• 2014

Objectives : The purpose of this study is to report the effect of Korean medical treatment on a patient with relapsing transverse myelitis. Methods : The patient was treated using acupuncture, pharmacopuncture, herbal medicine and other treatments including moxibustion and therapeutic exercise for 8 weeks. We evaluated the patient's motor grade with medical research council(MRC) scale and evaluated active range of motion in the hip, knee, and anke joint. Results : Through treatment the patient's motor grade and active range of motion all improved. Other symptoms such as lower limb hypoesthesia and residual urine sensation also showed improvement. Conclusions : We concluded that Korean medicine treatment had respectable effect in improving symptoms on the patient with relapsing transverse myelitis.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.5
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• pp.576-582
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• 2015

Generally, the fuel economy of hybrid electric vehicle (HEV) is effected by the size of each component. In this study the fuel economy for HEV of our own making is evaluated using backward simulator, where dynamic programming is applied. In a competition, the vehicle is running through the road course that includes many speed bumps and steep grade. Therefore, the new driving cycle including road grade is developed for the simulation. The backward simulator is also developed through modeling each component. A performance map of engine and motor for component sizing is made from the existing engine map and motor map adapted to the HEV of our own making. For optimal component sizing, the feasible region is defined by restricting the power range of power sources. Optimal component size for best fuel economy is obtained within the feasible region through the backward simulation.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.6 no.1
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• pp.27-33
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• 2011

This study was performed to report the effectiveness of oriental medical treatment on a patient with Guillain-Barre syndrome complaining both lower extremity weakness. The patient was diagnosed as Guillain-Barre syndrome and treated with acupuncture, electroacupuncture, physical therapy and herbal medicine. We have evaluated the efficacy of oriental medical treatment by measuring changes of motor grade and ambulatory condition according to period of hospitalization. After treatment, motor grade and ambulatory condition were improved. These results suggest that oriental medical treatment was effective on the patient with Guillain-Barre syndrome.

• The Journal of Internal Korean Medicine
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• v.37 no.2
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• pp.298-304
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• 2016

Objective: : This clinical study reports on the effect of Sunghyangjungki-san-gami and Banhabaeckchulchunma-tang-gami on hemiplegia, dizziness, and hiccupping caused by pontine infarction.Methods: This study was performed on one patient with hemiplegia, dizziness, and hiccupping caused by pontine infarction. The patient was treated by Sunghyangjungki-san-gami and Banhabaeckchulchunma-tang-gami from 6 January to 2 March 2015. The National Institutes of Health stroke scale (NIHSS), motor grade, and numerical rating scale (NRS) were used to assess the effectiveness of this treatment.Results: After treatment, the patient’s discomfort decreased significantly, and NIHSS, motor grade, and NRS scores were all improved.Conclusion: This clinical study suggests that traditional Korean medicine may be effective in treating hemiplegia, dizziness, and hiccupping caused by pontine infarction.

• Annals of Hepato-Biliary-Pancreatic Surgery
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• v.26 no.2
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• pp.190-198
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• 2022

Backgrounds/Aims: Traumatic pancreatic injury (TPI) is rare as an isolated injury. There is a trend to perform conservative treatment even in patients with complete duct dissection and successful treatment. This study reviewed our 20 years of experience in the management of TPI and assessed patient outcomes according to age group and treatment strategy. Methods: A retrospective analysis of patients diagnosed and treated with TPI at a level-I trauma center from 2000-2019. Patients were divided into two groups: adults and pediatrics. Conservative treatment cases were subjected to subgroup analysis. Level of evidence: IV. Results: Of a total of 77 patients, the mean age was 24.89 ± 15.88 years. Fifty-six (72.7%) patients had blunt trauma with motor vehicle accident. Blunt trauma was the predominant mechanism in 42 (54.5%) patients. Overall, 38 (49.4%) cases had grade I or II injury, 24 (31.2%) had grade III injury, and 15 (19.5%) had grade IV injury. A total of 30 cases had non-operative management (NOM). Successful NOM was observed in 16 (20.8%) cases, including eight (32.0%) pediatric cases and eight (15.4%) adult cases. Higher American association for the surgery of trauma (AAST) grade of injury was associated with NOM failure (16.7% for grade I/II, 100% for grade III, and 66.7% for grade IV injury; p = 0.001). An independent factor for NOM failure was female sex (69.2% in females vs. 29.4% in males; p = 0.03). Conclusions: High AAST grade TPI is associated with a high rate of NOM failure in both pediatric and adults.

• Journal of the Korean Society of Safety
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• v.38 no.3
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• pp.35-42
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• 2023

This study analyzed the current and temperature characteristics of major components of an induction motor during normal and abnormal operations as functions of the difference in the rated capacities of medium and large-sized motors widely used in industrial settings. The temperature rise equation of the induction motor winding was derived through locked-rotor operation experiments and linear regression analysis. When the ambient temperature is 40 ℃, the time to reach 155 ℃, the temperature limit of the insulation class (F class) of the winding of the induction motor, was confirmed to be 48 seconds for the 2.2 kW induction motor and 39 seconds for the 3.7 kW induction motor. This means that when the rated capacity is large or the installation environment is high temperature, the time to reach the temperature limit of the insulation class during locked-rotor operation is short, and the risk of insulation deterioration and fire is high. In addition, even if the EOCR (Electronic Over Current Relay) is installed, if the setting time is excessively set, the EOCR does not operate even if the normal and locked-rotor operation of the induction motor is repeated, and the temperature limit of the insulation grade of the winding of the induction motor is exceeded. The results of this study can be used for preventive measures such as the promotion of electrical and mechanical measures for the failure of induction motors and fire prevention in industrial sites, or the installation of fire alarm systems.

• Journal of Korean Neurosurgical Society
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• v.52 no.3
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• pp.267-269
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• 2012

Traumatic brachial plexus injuries can be devastating, causing partial to total denervation of the muscles of the upper extremities. Surgical reconstruction can restore motor and/or sensory function following nerve injuries. Direct nerve-to-nerve transfers can provide a closer nerve source to the target muscle, thereby enhancing the quality and rate of recovery. Restoration of elbow flexion is the primary goal for patients with brachial plexus injuries. A 4-year-old right-hand-dominant male sustained a fracture of the left scapula in a car accident. He was treated conservatively. After the accident, he presented with motor weakness of the left upper extremity. Shoulder abduction was grade 3 and elbow flexor was grade 0. Hand function was intact. Nerve conduction studies and an electromyogram were performed, which revealed left lateral and posterior cord brachial plexopathy with axonotmesis. He was admitted to Rehabilitation Medicine and treated. However, marked neurological dysfunction in the left upper extremity was still observed. Six months after trauma, under general anesthesia with the patient in the supine position, the brachial plexus was explored through infraclavicular and supraclavicular incisions. Each terminal branch was confirmed by electrophysiology. Avulsion of the C5 roots and absence of usable stump proximally were confirmed intraoperatively. Under a microscope, neurotization from the musculocutaneous nerve to two medial pectoral nerves was performed with nylon 8-0. Physical treatment and electrostimulation started 2 weeks postoperatively. At a 3-month postoperative visit, evidence of reinnervation of the elbow flexors was observed. At his last follow-up, 2 years following trauma, the patient had recovered Medical Research Council (MRC) grade 4+ elbow flexors. We propose that neurotization from medial pectoral nerves to musculocutaneous nerve can be used successfully to restore elbow flexion in patients with brachial plexus injuries.