• 한국항공운항학회지
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• 제27권3호
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• pp.106-111
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• 2019

Pilot has been fighting to get over fatigue during flight and thought it as a hinderance for safe flight. The fatigue related problem has been the biggest obstacle for aviation safety so far. Even though pilots and airlines try their best to overcome fatigue during flight, they couldn't overcome this problem. So the airliners let the pilot sleep during flight if pilots are too tired with the report. It is controlled rest used and managed by several European airliners. So this study tries to get Korean airline pilots' fatigue information and figure out the cause and reduce it.

• 한국정밀공학회지
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• 제20권7호
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• pp.70-77
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• 2003

The centerless through-feed grinding is performed by passing the workpiece between the grinding wheel and the regulating wheel. So, the amount of removed material around the leading end, of the workpiece is always more than that around the trailing end until the leading end leaves the grinding wheel. Because of this, there are differences in diameters along the workpiece axis during grinding, and workpiece axis is not parallel to the grinding wheel axis and the contact lines between the workpiece and wheels. Thus the ground workpiece shows tapering error inherently. To eliminate this error, the workpiece axis must be kept to be parallel to the grinding wheel axis. And, the direction of the workpiece axis can be controlled by the work-rest blade. Therefore, the effects of work-rest blade inclination angle on the through-feed centerless ground part are investigated in this study. As a result, it is found that there is a positive inclination angle of the work-rest blade for minimizing the tapering error of a ground workpiece.

• 한국농림기상학회지
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• 제7권3호
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• pp.185-191
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• 2005

An accurate prediction of dormancy release and bud burst in temperate zone fruit trees is indispensable for farmers to plan heating time under partially controlled environments as well as to reduce the risk of frost damage in open fields. A thermal time-based two-step phenological model that originated in Italy was applied to two important grapevine cultivars in Korea for predicting bud-burst dates. The model consists of two sequential periods: a rest period described by chilling requirement and a forcing period described by heating requirement. It requires daily maximum and minimum temperature as an input and calculates daily chill units (chill days in negative sign) until a pre-determined chilling requirement for rest release is met. After the projected rest release date, it adds daily heat units (anti-chill days in positive sign) to the chilling requirement. The date when the sum reaches zero isregarded as the bud-burst in the model. Controlled environment experiments using field sampled twigs of 'Campbell Early' and 'Kyoho' cultivars were carried out in the vineyard at the National Horticultural Research Institute (NHRI) in Suwon during 2004-2005 to derive the model parameters: threshold temperature for chilling and chilling requirement for breaking dormancy. The model adjusted with the selected parameters was applied to the 1994-2004 daily temperature data obtained from the automated weather station in the NHRI vineyard to estimate bud burst dates of two cultivars and the results were compared with the observed data. The model showed a consistently good performance in predicting the bud burst of 'Campbell Early' and 'Kyoho' cultivars with 2.6 and 2.5 days of root mean squared error, respectively.

• 한방비만학회지
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• 제13권2호
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• pp.58-65
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• 2013

Objectives: The objective of this study was to analyse the methods being used to control food intake and physical activity in RCTs of human obesity. Methods: A total of 21 randomized controlled trials (RCTs) were investigated. Nine of which were domestic studies from "http://oasis.kiom.re.kr" and the other of which were foreign studies from systematic reviews of RCTs on herbal medicine for treatment of human obesity. Results: According to domestic studies, "low calorie diet" were recommended in five cases of the domestic studies, "maintain current dietary habit" were recommended in two and no information on diet was two. Considering the seven cases where the information on diet was available, patients' food intake were checked at every visit in six cases. Only two cases among the six had been dropped owing to the violation of dietary habit by patients. Exercises were prohibited in two cases, "maintain current level of phisical activity" were recommended in three cases and, from the rest, no information was available. The level of physical activity were not strictly controlled by any means hence no drop out. According to foreign studies, "low calorie diet" were recommended in two cases, "very low calorie diet (less than 700 kcal/day)" in one case, "maintain current dietary habit" in two cases, "do not eat fat" in two cases and no information was available in the rest five cases. Exercises which concerns spending about 300 kcal/day was recommended in one case, "moderate exercise" were recommended in three cases, "maintain current level of physical activity" were recommended in three cases and no information available in the rest five cases. Conclusions: In order to improve the accuracy of RCT, for the dietary side, researchers should record patient food intake at every visit by means of 24-hour dietary recall methods. This can be supplemented by multiple choice survey that are designed to help patients to diagnose themselves more accurately leading to less bias. For the exercise side, it is highly recommended to confine the exercises to walking only so as to quantify the amount of physical activity more easily by using pedometer.

• Journal of Power Electronics
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• 제16권2호
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• pp.498-511
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• 2016

This paper presents a single-phase five-level inverter controlled by two novel pulse width modulation (PWM) switching techniques. The proposed PWM techniques are designed based on minimum switching power loss and minimum total harmonic distortion (THD). In a single-phase five-level inverter employing six switches, the first proposed PWM technique requires four switches to operate at switching frequency and two other switches to operate at line frequency. The second proposed PWM technique requires only two switches to operate at switching frequency and the rest of the switches to operate at line frequency. Compared with conventional PWM techniques for single-phase five-level inverters, the proposed PWM techniques offer high efficiency and low harmonic components in the output voltage. The validity of the proposed PWM switching techniques in controlling single-phase five-level inverters to regulate load voltage is verified experimentally using a 100 V, 500 W laboratory prototype controlled by dspace 1103.

• 한방재활의학과학회지
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• 제33권3호
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• pp.67-78
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• 2023

Objectives To evaluate the evidence supporting the efficacy and safety of electroacupuncture for lumbar spinal stenosis. Methods We searched eight electronic databases (PubMed, EMBASE, Cochrane Library, Chinese Academic Journals, Research Information Sharing Service, ScienceOn, KMBASE, DBpia) and related two journals up to March 2023. We included randomized controlled trials of testing electroacupuncture for lumbar spinal stenosis patients. The methodological quality of relevant randomized controlled trials assessed by the Cochrane risk of bias tool. Results Among 90 articles that were searched, seven randomized controlled trials involving 474 participants were finally selected in this systematic review. Electroacupuncture was more effective on lumbar spinal stenosis compared with other treatments including analgesics, acupuncture, bed rest and exercise therapy, but showed ambiguous effect compared with physical therapy. Most of the side effects and adverse reactions were reported as minor and temporary. Conclusions Electroacupuncture for lumbar spinal stenosis was more effective than analgesics, acupuncture, bed rest and exercise therapy. In terms of safety, it was limited because there are many papers that do not mention side effects and adverse reactions related to electroacupuncture. Additional studies are needed to determine the effect of electroacupuncture on lumbar spinal stenosis.

• 대한인간공학회지
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• 제13권2호
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• pp.43-48
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• 1994

Among many kinds of odors, some are known to have effects of sedation or stimulation on brain activity. In this study, brain activity levels affected by four kinds of fragrance0lemon, lavender, jasmine, and rose-were tested using EEG recording. In the first experiment, the quality of alpha wave was examined under controlled rest condition. In the second experiment, the event-related potential (ERP) and contingent negative variation (CNV) were investigated during a simple reaction tasks (SRT) against auditory signal. EEG data obtained for the rest condition were analyzed suing "3-Dimensional Viewer)" which was developed by ourselves to show the chaotic attractor of the signal. Power spectrum were also calculated using FET. EEG data obtained during the SRT were analyzed by comparing CNV amplitudes about each odor condition. Results confirmed the sedative effect of the lemon and the lavender, and the stimulative effect of the jasmine and the rose.

• 산업경영시스템학회지
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• 제26권1호
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• pp.22-29
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• 2003

The study was to evaluate psychological and physiological changes of simulator sickness in the controlled condition of driving a car (1 hr. at speed of 60 km/h) in a graphic simulator. Simulator sickness was measured and analyzed every 5 min using both subjective responses(i.e., Simulator Sickness Questionnaire) and Physiological signals(EEG, HRV, Skin Temperature, GSR). The results showed that there was significant differences in subjective response 10 min after the main experiment. From 10 min after the driving, the level of subjective simulator sickness increased significantly, relative one of the rest condition. There also was significant differences in physiological responses between the rest and the 5 min after from the start of driving : for EEG, $\delta$ and $\theta$ at Fz area increased, while $\alpha$ decreased; the averaged R-R interval and skin temperature decreased; LF/HF and GSR increased. The results indicated that simulator sickness was induced by activation of the autonomic nerves and inactivation of the central nerves.

• Corrosion Science and Technology
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• 제9권1호
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• pp.29-33
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• 2010

Laser machining technique, which is used focusing pulse YAG laser beam irradiation was applied to form area ratio controlled model cut-edge on pre painted Zn coated steels. A corrosion behavior of formed model cut-edge was investigated by rest potential measurement in 1 mol $m^{-3}$ NaCl with and without 0.5 kmol $m^{-3}$ $H_3BO_4$/0.05kmol$m^{-3}$ $Na_2B_4O_7$. The rest potential showed almost constant value with fluctuations. The amplitude of fluctuations increased with exposed area of steel surface. White corrosion products of zinc oxide and simonkollite was formed after the experiments at the formed model cut-edge.

• 대한정형외과학회지
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• 제54권5호
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• pp.411-417
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• 2019

목적: 슬관절 인공관절 전치환술(total knee arthroplasty, TKA) 시행 후 일회 주사 내전근관 차단술(single injection adductor canal block, SACB), 지속적 내전근관 차단술(continuous adductor canal block, CACB), 그리고 경피성 buprenorphine 병합 사용을 통한 임상결과를 비교하였다. 대상 및 방법: TKA 후 통증 조절을 시행한 125명의 환자들을 대상으로 SACB를 단독 시행한 I군(41명), SACB 및 경피성 buprenorphine 10 ㎍/h를 병합 사용한 II군(44명), CACB를 시행한 III군(40명)으로 분류하여 임상결과를 후향적으로 비교하였다. 통증 조절 지표로 visual analogue scale (VAS)을 사용하였으며, 술 후 12시간, 24시간, 48시간째 침상 안정 상태에서의 VAS (VAS-Rest)와 술 후 24시간 및 48시간째 continuous passive motion (CPM) 중 VAS (VAS-CPM), 그리고 술 후 48시간 동안 정맥주사 patient controlled analgesia (PCA)를 위한 약물(부토판, 트리돌, 케토락)의 사용량을 측정하였다. 기능 개선 지표로 술 후 48시간 동안 오심 및 구토 증상 횟수, 술 후 24시간 및 48시간째 최대 슬관절 굴곡 범위와 최대 자가 보행 거리, 그리고 총 재원 기간을 기록하여 비교하였다. 결과: VAS-Rest는 술 후 12시간째는 유의한 차이가 없었으나 술 후 24시간 및 48시간째와 VAS-CPM, PCA 총 사용량에서 II, III군이 I군보다 유의하게(p<0.05) 더 낮은 결과를 나타내었다. 그리고 오심 및 구토 증상 횟수, 최대 슬관절 굴곡 범위와 자가 보행 거리, 총 재원 기간은 세 군 간의 유의한 차이를 보이지 않았다. 결론: SACB 및 경피성 buprenorphine 병합 사용은 초기 통증 조절에 우수한 결과를 보였으며, 카테터로 인한 문제가 없고, 사용의 편의성 및 신 기능에 대한 안전성이 있기 때문에 TKA 후 유용한 통증 조절 방법이 될 수 있다.