• Journal of Power Electronics
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• 제18권3호
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• pp.694-701
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• 2018

This paper proposes a new single-phase power converter topology for changing the frequency of AC voltage. The proposed single-phase frequency converter (SFC) includes a T-type multi-level power converter (TMPC), a frequency decoupling transformer (FDT) and a digital signal processor (DSP). The TMPC can convert a 60 Hz AC voltage to a DC voltage and then convert the DC voltage to a 50 Hz AC voltage. Therefore, the output currents of the two T-type power switch arms have 50 Hz and 60 Hz components. The FDT is used to decouple the 50 Hz and 60 Hz components. The salient feature of the proposed SFC is that only one power electronic converter stage is used since the functions of the AC-DC and DC-AC power conversions are integrated into the TMPC. Therefore, the proposed SFC can simplify both the power circuit and the control circuit. In order to verify the functions of the proposed SFC, a hardware prototype is established. Experimental results verify that the performance of the proposed SFC is as expected.

• 로봇학회논문지
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• 제5권3호
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• pp.270-277
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• 2010

Various robot platforms have been designed and developed to perform given tasks in a hazardous environment for the purpose of surveillance, reconnaissance, search and rescue, and etc. We have considered a terrain adaptive hybrid robot platform which is equipped with rapid navigation on flat floors and good performance on overcoming stairs or obstacles. Since our special consideration is posed to its flexibility for real application, we devised a design of a transformable robot structure which consists of an ordinary wheeled structure to navigate fast on flat floor and a variable tracked structure to climb stairs effectively. Especially, track arms installed in front side, rear side, and mid side are used for navigation mode transition between flatland navigation and stairs climbing. The mode transition is determined and implemented by adaptive driving mode control of mobile robot. The wheel and track hybrid mobile platform apparatus applied off-road driving mechanism for various professional service robots is verified through experiments for navigation performance in real and test-bed environment.

• 설비공학논문집
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• 제26권6호
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• pp.294-300
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• 2014

In this study, we investigated and evaluated the air conditioning operation of the driver according to the temperature difference between the inside and outside of a car parked outside during the summer. We suggest including a comfort mode to the car air conditioning system to improve the thermal comfort of the driver, in which the comfort can be maintained for a longer time. For the a result of our experiment, in the cases with temperature of above $45^{\circ}C$ inside of the car, the subjects preferred strong air blow with the face and the arms in the direction of the blow. In the cases with temperature of below $40^{\circ}C$ inside of the car, the subjects preferred lower volume of air blow. In the temperature below $28.1^{\circ}C$ inside of the car, the mean temperature on the skin of the driver reached the comfort zone.

• Journal of Electrical Engineering and Technology
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• 제12권3호
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• pp.1227-1234
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• 2017

The two-degree-of-freedom direct drive induction motor, which is capable of linear, rotary and helical motion, has a wide application in special industry such as industrial robot arms. It is inevitable that the linear motion and rotary motion generate coupling effect on each other on account of the high integration. The analysis of this effect has great significance in the research of two-degree-of-freedom motors, which is also crucial to realize precision control of them. The coupling factor considering the coupling effect is proposed and addressed by 3D finite element method. Then the corrected mathematical model is presented by importing the coupling factor. The results from it are verified by 3D finite element model and prototype test, which validates the corrected mathematical model.

• 전력전자학회논문지
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• 제17권5호
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• pp.409-415
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• 2012

This paper presents a new software-based on-line dead-time compensation technique for a single-phase grid-connected photovoltaic (PV) inverter system. To prevent a short circuit in the inverter arms, a switching delay time must be inserted in the pulse width modulation (PWM) signals. This causes the dead-time effect, which degrades the system performance around zero-crossing point of the output current. To reduce the dead-time effect around the zero-crossing point of grid current, a harmonic mitigation of grid current is used as an additional part of the synchronous frame current control scheme. This additional task mitigates the harmonic components caused by the dead-time from the grid current. Simulation and experimental results are shown to verify the effectiveness of the proposed dead-time compensation method in the single-phase grid-connected inverter system.

• 신경치료
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• 제22권3호
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• pp.25-29
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• 2018

Purpose In this study, 45 students were divided into task - oriented group, task - oriented intermittent group, and continuous group, and the effect of each variable on learning was changed to angle of the arms' we checked. Methods This study was conducted for 45 days from March 13 to 18, 2017 for five days in the 20 generals living in Changwon city. Dart and goniometer were used for the measurement. In the exercise program, darts were placed on a smooth, hard surface of 1.5M height and the distance to the subject was set 1.5m away. In the dart throw practice, all three groups were marked with an elbow flexion $30^{\circ}$ on the wall, and the subjects were instructed to throw the dart at that point. Results Comparisons between groups showed significant differences between the continuous task-oriented training group and the intermittent task-oriented training group and the control group at the end of training (*** P <0.001). Conclusion This study showed that the intermittent task-oriented training method showed the highest effect (*** P <0.001), which proved that the intermittent method is the most effective exercise method among the three groups.

• Advances in nano research
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• 제14권6호
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• pp.591-602
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• 2023

In the present study, capability of nanobiotics in repairing tendon injuries commonly occur in Taekwondo sport is investigated and some approaches are proposed. In this regard, a brief review on the types and application of nanobiotics is presented. Their capabilities and limitation are discussed. Next, different type of tendon injuries in Taekwondo athletes are discussed along with their treatment approaches. Based on the presented data, a nano-scale feasible robot model carrying nanobiotics is proposed for repairing tendons. Finite element simulations is also conducted to show the effectiveness of the repairing process using nanorobots equipped with nanobiotics. This repairing procedure is a combination of mechanical and chemical treatments. The results indicated that using nanobiotics on nanorobots arms in the repair of tendon injuries has many benefits. First, drug delivery is directly injected to the target section. Second, Due to the nanorobots small sizes more acute treatment is possible. Finally, since the control of the nanorobots are assisted with computers, the possibility of human error reduces significantly. The proposed method of the present study could be utilized by other scientists and technological industry in developing final nanorobots with nanobiotics carrying capacity.

• 근관절건강학회지
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• 제1권1호
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• pp.97-115
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• 1994

The purpose of this study was to examine the reliability and validity of the observed behaviors of subjects who suffered from low back pain with spinal diseases, Thirty two low back pain patients admitted on the neurosurgical unit in an army hospital were compared with 30 normal controls belonged to an army unit, by means of matching the age, hight and weight. Observed pain behaviors were developed by the researcher on the bases of literature and patient observation. This tool consists of 18 behaviors seperated into two major groups : mutually exclusive and concomittent behaviors. The mutually exclusive behaviors included coding cathegories for 6. body motions assumed by the subjects during the observation session. These 6 standardized motions consisted of sitting from standing first, and serially tying down, reclining, sitting again, and then standing, 6 steps walking. Concomittent behaviors consisted of 12 observable patterns that can be observed systematically from the face, grimacing, bracing, rubbing, walking with arms fixed, support with hands on sitting or standing, guarded movement, limping, unbalaced weightbearing, stopped movement from tying position to sitting, sighing and graoning. Subjects were videotrecorded as they performed a 6-standardized sequence of motions, simultanously researcher measured the time spent performing each motion and step length. Patients were asked torate their subjective pain score on the 10 mm graphic rating scale ranging from 'no pain' to 'sever pain'. For scoring of the pain behaviors, two trained nursing officiers independently and simutanously viewwd each videorecording and checked subject 'pain behaviors at the observational item checklist. The result of the study are summarized as follows : 1. Reability of the observational tool was a=.845. 2. Spearman's rho and percentage agreement were p=.97 and 81.7 persent respectively, that indicate adequate interrater reability of this tool. 3. The sensitivity rate of the tool was .875 while specificity rate .866 for differentiating patient from the normal. 4. When difference in the objective pain indices between patient group and control were compared, there was significant difference of all indices, such as pain behavior(t=7.71, p=.0001). spent time performing motion(t=14.2, p=.0001), step length (t=-10.72, p=.0001). 5. There were differences in the objective indices the subjective pain subgroups (low, medium, high). Differences in the mean score of objective pain behavior (F=6.376. p=.005) and spent time for moyion(F=4.631, p=.018). But there were no significant differences in the step length among the subgroups(F=.667, p=.521). 6. Highly correlated pain behavior items wiyh subjective pain score were 'stopped movement from lying position to sitting', 'limping', 'support with hands on sitting or standing', 'bracing', 'guarding' and 'walking with arms fixed'. In summary, although some of rho behavior items such as sighing and groaning in this study could not be observed because of videotaped datd, the reliability and validity of the over all observation method were satifactory. Thus, the results of the present study demonstrate rye potetional utility of the tool in assessing objective pain complementing self-reported pain in low back pain patients.

• Asian Pacific Journal of Cancer Prevention
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• 제16권12호
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• pp.5075-5079
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• 2015

Background: Adverse effects of treatment prolongation beyond 8 weeks with radiotherapy for cervical cancer have been established. Clinical data also show that cisplatin increases the biologically effective dose of radiotherapy. However, there are no data on the effect of overall treatment time in patients with locally advanced cervical cancer treated with concomitant chemo-radiotherapy (CCRT) in an Indian population. The present study concerned the feasibility of concurrent chemotherapy and interspacing brachytherapy during the course of external radiotherapy to reduce the overall treatment time and compare the normal tissue toxicity and loco-regional control with a conventional schedule. Materials and Methods: Between January 2009 and March 2012 fifty patients registered in the Gynaecologic Oncology Clinic of Institute Rotary Cancer Hospital with locally advanced cervical cancer (FIGO stage IIB-IIIB) were enrolled. The patients were randomly allocated to treatment arms based on a computer generated random number. Arm I (n=25) treatment consisted of irradiation of the whole pelvis to a dose of 50 Gy in 27 fractions, and weekly cisplatin $40mg/m^2$. High dose rate intra-cavitary brachytherapy (HDR-ICBT) was performed after one week of completion of external beam radiotherapy (EBRT). The prescribed dose for each session was 7Gy to point A for three insertions at one week intervals. Arm II (n=25) treatment consisted of irradiation of the whole pelvis to a dose of 50 Gy in 27 fractions. Mention HDR-ICBT ICRT was performed after 40Gy and 7Gy was delivered to point A for three insertions (days 23, 30, 37) at one week intervals. Cisplatin $20mg/m^2/day$ was administered from D1-5 and D24-28. Overall treatment time was taken from first day of EBRT to last day of HDR brachytherapy. The overall loco-regional response rate (ORR) was determined at 3 and 6 months. Results: A total of 46 patients completed the planned treatment. The overall treatment times in arm I and arm II were $65{\pm}12$ and $48{\pm}4$ days, respectively (p=0.001). At three and six months of follow-up the ORR for arm I was 96% while that for arm II was 88%. No statistically significant difference was apparent between the two arms. The overall rate of grade ${\geq}3$ toxicity was numerically higher in arm I (n=7) than in arm II (n=4) though statistical significance was not reached. None of the predefined prognostic factors like age, performance status, baseline haemoglobin level, tumour size, lymph node involvement, stage or histopathological subtype showed any impact on outcome. Conclusions: In the setting of concurrent chemoradiotherapy a shorter treatment schedule of 48 days may be feasible by interspacing brachytherapy during external irradiation. The response rates and toxicities were comparable.

• Asian Pacific Journal of Cancer Prevention
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• 제15권8호
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• pp.3419-3424
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• 2014

Background: Our aim was to conduct a meta-analysis to compare the efficacy and safety of pemetrexed and docetaxel for non-small cell lung cancer (NSCLC). Materials and Methods: We systematically searched the Cochrane Library, PubMed, Embase, China Biology Medicine Database for randomized controlled trials (RCTs) comparing the efficacy and toxicities of pemetrexed versus docetaxel as a treatment for advanced NSCLC. We limited the languages to English and Chinese. Two reviewers independently screened articles to identify eligible trials according to the inclusion and exclusion criteria and assessed the methodological quality of included trials, and then extracted data. The meta-analysis was performed using STATA12.0. Results: Six RCTs involving 1,414 patients were identified. We found that there was no statistically significant differences in overall response rate, survival time, progression-free survival, disease control rate, and 1-2yr survival rate (p>0.050) but it is worthy of mention that patients in the pemetrexed arms had significantly higher 3-yr survival rate (P=0.002). With regard to the grade 3 or 4 hematological toxicity, compared with docetaxel, pemetrexed led to lower rate of grade 3-4 febrile neutropenia, neutropenia, and leukocyts toxicity (p<0.001). There was no significant difference in anemia between the two arms (p=0.08). In addition, pemetrexed led to higher rate of grade 3-4 thrombocytopenia toxicity (p=0.03). As for the non-hematological toxicities, compared with docetaxel, pemetrexed group had lower rate of grade 3-4 diarrhea and alopecia. Conclusions: Pemetrexed was almost as effective as docetaxel in patients with advanced NSCLC. At the same time, pemetrexed might increase the 3-yr survival rate. As for safety, pemetrexed led to lower rate of grade 3-4 febrile neutropenia, neutropenia, leukocytes, diarrhea and alopecia toxicity. However, it was associated with a higher rate of grade 3-4 thrombocytopenia.