• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.546-549
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• 1995

This paper presents a control of washing machine using ER clutch and brake actuators. After analyzing field- dependent torque of the actuators on the basis of Bingham model of the ER fluid, two sets of cylindrical ER clutch and brake are manufactured. The governing equation of motion for washing and dehydrating are derived by considering actuators' dynamics. Subsequently, PID controllers are designed to achieve desired rotational motions and tracking control results are provided to demonstrate the effectiveness of the proposed method.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.970-977
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• 1995

Effect of garlic intake on the antifatigue and fatigue recovery during prolonged exercise have been investigated. 16 male college students(8 persons of control group and the same numbers of garlic intake group), aged from 20 to 22 years, were subjected to the restricted experiment and maintained their same menu with exercise in life pattern during 14 days of program. In garlic intake group, 30g of garlic was given with every 3 meal per day to each person. A significant increase in HDL-cholesterol level was shown in the garlic intake group while total cholesterol, LDL-cholesterol and lactate level decreased by garlic intake. Lactate dehydrogenase activity in serum increased by garlic intake, however garlic intake was not significantly affected on Vo2, Vco2, ventilation, respiratory quotient. In conclusion, garlic intake seemed to be effective for antifatigue and tatigue recovery during prolonged exercise.

• The Transactions of the Korean Institute of Power Electronics
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• v.7 no.6
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• pp.524-530
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• 2002

A control of the body posture and movement is maintained by the vestibular system, vision, and proprioceptors. Afferent signals from those receptors are transmitted to the vestibular nuclear complex, and the efferent signals from the vestibular nuclear complex control the eye movement and skeletal muscle contract. The postural disturbance caused by loss of the vestibular function results in nausea, vomiting, vertigo and loss of craving for life. The purpose of this study is to develop a off-vertical rotatory system for evaluating the function of semicircular canals and otolith organs, selectively, and visual stimulation system for- stimulation with horizontal, vortical and 3D patterns. The Off-vortical axis rotator is composed of a comportable chair, a DC servo-motor with reducer and a tilting table controlled by PMSM. And a double feedback loop system containing a velocity feedback loop and a position feedback loop is applied to the servo controlled rotatory chair system. Horizontal, vertical, and 3D patterns of the visual stimulation for applying head mounted display are developed. And wireless portable systems for optokinetic stimulation and recording system of the eye movement is also constructed. The gain, phase, and symmetry is obtained from analysis of the eye movement induced by vestibular and visual stimulation. Detailed data were described.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.8
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• pp.126-134
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• 1998

본 연구에서는 회전운동을 제어하기 위한 새로운 작동기로서 전기장에 대하여 매우 빠른 응답특성을 갖고 있는 두 쌍의 실린더형 ER(electro-rheological) 클러치/브레이크 작동기를 제안하였다. 자체조성 된 ER유체의 빙햄특성 모델을 실험적으로 도출하였으며, 이와 연계한 작동기 모델을 구성하여 전기장에 따른 전달 및 제동 토크를 해석한 후 알맞은 크기의 클러치/브레이크 작동기를 제작하였다. 제작된 작동기의 동적특성(시상수 등)을 작동기 모델에 고려하기 위하여 계단입력 전기장에 따른 과도응답 실험을 클러치와 브레이크 모드에서 각각 수행하였다. 제안된 작동기의 응용성을 보이기 위하여 두쌍의 작동기로 구동되는 실험실 차원의 소형 와권식 세탁기 시스템을 구성한 후 동적지배방정식을 유도하다. 각 작동기와 연계된 PID제어기를 설계하여 세탁과 탈수시의 회전운동을 제어하였으며, 부하질량의 변화에 대한 작동기 시스템의 제어 효율성과 장시간 운전을 통한 제어 내구성 실험을 수행하였다.

• The Journal of the Korea Contents Association
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• v.8 no.10
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• pp.301-308
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• 2008

The purpose of this study was to investigate the change of physical fitness, MDA, SOD after short-term weight reduction through exercise, food restriction and exhalation of sweat among Taekwondo players. The subjects ten male collage Taekwondo players with excellent practical skills, and more than seven years of experiences. They were asked to reduce about 5% of their body weight in seven days. Physical fitness levels were analyzed through grip strength, muscle endurance, flexibility, power, agility, balance, reaction time and MDA and SOD through blood test. The results of this study were as follows; First, there was no significant change in physical fitness due to short-term weight reduction in muscle strength, muscle endurance, flexibility, power, agility, balance and reaction time. Second, The change of MDA and SOD, resulting from short-term weight reduction did not show significant difference statistically. Therefore, the results of this study indicate that the Taekwondo players' short-term weight reduction of 5% of their body weight did not influence on their athletic performance and physiological capacity. Therefore athletes and coaches should endeavor to take exercise, dietary, and dehydration into consideration when conducting 5% of their body weight reduction in a week.

• Journal of the Korean Society of Radiology
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• v.81 no.1
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• pp.243-247
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• 2020

We report a rare case of hyperglycemia-related osmotic demyelination syndrome (ODS) with focus on the imaging findings. A 61-year-old man with diabetes was admitted for general weakness and severe thirst. A few days later, he complained of dysarthria, dysphasia, and dysmetria. Laboratory examinations showed significant hyperglycemia, but normal electrolyte levels. Brain MRI revealed T2-signal abnormalities that were symmetrical, non-space occupying, and located in the central pons with a peripheral sparing pattern, which were suggestive of ODS. In addition, subsequent MRI revealed progression of signal hyperintensity; however, the patient's symptoms improved.

• The Journal of the Korea Contents Association
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• v.10 no.10
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• pp.237-245
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• 2010

Nerve conduction studies (NCS) are the most objective measure of nerve function and essential for the diagnosis of sub-clinical neuropathy in diabetes mellitus and diabetic polyneuropathy (DPN). This study evaluates the characteristic of electrophysiological abnormalities in DPN. Electrodiagnostic data from 120 patients with diabetic polyneuropathies and 77 control subjects were reviewed. Motor nerve conduction velocities (MNCV), distal motor latencies (DML), compound muscle action potential (CMAP) amplitudes, No potential frequency and conduction block were analyzed. Data were normalized based on normative reference values, and the proportion of nerves with abnormal values in the lower and upper limbs were evaluated. DPN was systemic demyelinating peripheral polyneuropathy and more severe abnormal nerve conduction was found in lower limbs than in upper limbs. The abnormal degree was more severe in peroneal nerve. It was no statistically significant difference of conduction block in control and DPN group. Our findings suggest that DPN had more common and severe peroneal nerve involvement in the motor nerve conduction studies (MNCS). These findings have important implications for the electrophysiological evaluation of DPN.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.1 no.1
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• pp.5-12
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• 2001

아시아 및 한국에서 처음 발견된 3명의 소아 Ethylmalonic encephalopathy (EE) 환자들은 riboflavin을 이용한 치료법에 점진적인 호전을 보인 것으로 나타났다. Ethylmalonic aciduria가 3가지 효소-2-methyl-branched-chain acyl CoA dehydrogenase (2MBCAD), iso-valeryl CoA dehydrogenase (IVCAD), 그리고 short-chain acyl CoA dehydrogenase (SCAD) - 들의 부분적인 결함으로 생긴다는 가설하에 dehydrogenase (탈수효소)의 보조 효소인 riboflavin이 부분적으로 나마 치료 과정에서 어떤 역할을 수행하는지의 여부를 살펴보았다. 다음의 세 증례에서 riboflavin 혹은 coenzyme Q10을 병행하여 치료한 결과 인지 행동(cognitive behavior)과 만성 점액성 설사(chronic mucoid diarrhea)가 호전된 것으로 관찰되었다. 또한, 치료 후 운동 기능도 일부 호전되었다. EE의 질병 발생 기전이 현재까지 완전히 밝혀지지는 않았지만, 세 명의 EE 환자들의 치료경과를 관찰하여 위의 가설을 뒷받침 할 수 있었다.

• The Transactions of the Korean Institute of Power Electronics
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• v.6 no.4
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• pp.325-332
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• 2001

The vestibular system located in the inner ear controls reflex body posture and movement, It has the semicircular canals sensing an angular acceleration and the otolith organs sensing a linear acceleration. With this organic signal, medical doctor decide if a person has disease or not. To obtain this data, a precision stimular system is considered. Robust control is needed to obtain eye signals induced by off-vertical axis rotation because of an unbalanced load produced by tilting the axis of the system upto 30 degrees. In this study, off-vertical axis rotatory system with visual stimulation system are developed. This system is consisted of head mounted display for generating horizontal, vertical, and three dimensional stimulus patterns. Furthermore wireless recording system using RF modem is considered for noiseless data transmission. Detailed data was described.

• Membrane Journal
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• v.28 no.5
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• pp.340-350
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• 2018

In the present study, crystallographically b- and c-axis oriented mordenite zeolite membranes were prepared and their pervaporative ethanol dehydration was investigated. The seed layer with a high coverage grew to be c-axis oriented dense layer, while the seed layer with a low coverage grew to be b-axis oriented layer. This phenomenon could be explained by the evolutionary selection growth mechanism. The b-axis grown membrane with 8-membered rings showed a high separation factor of above 1000 and a considerable total flux of around $0.2kg/m^2h$. The c-axis grown, columnar structured membrane with 8- and 12-membered rings showed a low separation factor of less than 200 and a relatively high total flux of around $0.25kg/m^2h$. The high performance of b-axis grown membrane was due to the relatively small opening of 8-membered rings. Water molecules can freely permeate through the openings, but ethanol molecules, difficultly. Therefore, in the present study, we introduced a new method to control crystallographic orientation of mordenite membrane by changing seeding amount of needle-like crystals, and elucidated that b-axis oriented mordenite membrane showed better performance than c-axis grown mordenite membrane.