• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.8
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• pp.13-22
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• 2010

Independent-Gate-Mode Double-Gate(IGM-DG) MOSFET overcomes the limitation of bulk-MOSFET's channel controllability and enables to control the front and back-gate voltages independently. Therefore, circuit designs utilizing the IGM-DG MOSFETs provide the advantage of setting 4-terminal freely, hence achieving not only the performance improvement but also the larger scale integration. This paper presents a 15Gb/s optical receiver with a 1.0V power supply voltage, which consists of a transimpedance amplifier (TIA), a feedforward limiting amplifier (LA), and an output buffer. HSPICE simulations were conducted to confirm the circuit performance, and also to verify the circuit stability issues which may occur from the variations of process and supply voltage.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.8
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• pp.23-28
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• 2010

In this paper, comparative analysis of digital and analog performances of strained-silicon PMOSFETs with different carrier direction were performed. ID.SAT vs. ID.OFF and output resistance, Rout performances of devices with <100> carrier direction were better than those of <110> direction due to the greater carrier mobility of <100> channel direction. However, on the contrary, NBTI reliability and device matching characteristics of device with <100> carrier direction were worse than those with <110> carrier direction. Therefore, simultaneous consideration of analog and reliability characteristics as well as DC device performance is highly necessary when developing mobility enhancement technology using the different carrier direction for nano-scale CMOSFETs.

• The Journal of Korean Obstetrics and Gynecology
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• v.18 no.3
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• pp.192-202
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• 2005

Purpose : To investigate relation between Heart rate variability(HRV) and Kupperman's index. Methods : From 2004, 3, 15 to 2004, 4, 10, a total 18 female patients(age 40-61) was recruited. but 2 patients was excluded. one was under hormone raplacement therapy, the other was under drug treatment. We measured patient's HRV by SA-2000E(Medicore Co., Ltd., Korea), and they fulfilled kupperman's index and　qustionnaire.　Results : The mean age of patient was 50.13${\pm}$5.78 years. 6 of 16 patients was menopause, 12 of 16 patients had menstruation. half of 16 patients had a understanding about climacteric syndrome. Investigating relation between HRV and kupperman's index, kupperman's index had positive correlation with heart rate significantly. Kupperman's index had negative correlation with SDNN significantly. Kupperman's index had negative correlation with RMS-SD significantly. Conclusion : In this study, we presented relation between HRV and kupperman's index. Furthermore, large scale study is required.

• Journal of Korean Neurosurgical Society
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• v.60 no.1
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• pp.60-66
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• 2017

Objective : Sacral insufficiency fracture (SIF) contributes to severe low back pain. Prolonged immobilization resulting from SIF can cause significant complications in the elderly. Sacroplasty, a treatment similar to vertebroplasty, has recently been introduced for providing pain relief in SIF. The purpose of this study is to investigate the clinical short-term effects of percutaneous sacroplasty on pain and mobility in SIF. Methods : This study is conducted prospectively with data collection. Sixteen patients (3 men and 13 women) with a mean age of 77.5 years (58 to 91) underwent sacroplasty. Patients reported visual analogue scale (VAS; 0-10) and Oswestry disability index (ODI; 0-100%) scores. VAS and ODI scores were collected preoperatively and again at one day, one month, and three months postoperatively. Questionnaires measuring six activities of daily living (ADLs) including ambulating, performing housework, dressing, bathing, transferring from chair, and transferring from bed were collected. Ability to perform ADLs were reported preoperatively and again at three months postoperatively. Results : The mean preoperative VAS score ($mean{\pm}SD$) of $7.5{\pm}0.8$ was significantly reduced to $4.1{\pm}1.6$, $3.3{\pm}1.0$, and $3.2{\pm}1.2$ postoperatively at one day, one month, and three months, respectively (p<0.01). The mean ODI score (%) also significantly improved from $59{\pm}14$ preoperatively to $15.5{\pm}8.2$ postoperatively at one month and $14.8{\pm}8.8$ at three months (p<0.01). All ADL scores significantly improved at three months postoperatively (p<0.01). Conclusion : Percutaneous sacroplasty alleviates pain quickly and improves mobility and quality of life in patients treated for SIF.

• The Journal of Korean Society for School & Community Health Education
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• v.15 no.3
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• pp.105-125
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• 2014

Background: The purpose of this study was to evaluate reliability and validity of a 27-item Korean Version of the Impact of Weight on Quality of Life in adolescents ($IWQOL-Kids^{(C)}$: Korean Version). Methods: This instrument was administered to 872 adolescents (mean z-BMI: 2.61, mean $age{\pm}SD$: $13.9{\pm}1.2$, male: 51.9%). Reliability was tested by internal consistency method and item analysis, validity test was performed by index of content validity, exploratory factor analysis, confirmatory factor analysis and concurrent validity. Sensitivity was tested by ANOVA and t-test. Analyses were performed using SPSS and Amos 18.0. Results: By an exploratory factor analysis, 4 factors were extracted; 'Body esteem' consisted of 9 items with 35.9% of variance (social life: 6 items, 10.23%, physical comfort: 6 items, 8.21%, family relations: 6 items, 7.0%). Four factors explained 61.34% of total variance. Internal consistency coefficients ranged from .766 to .929 for scales on 27 items and equal to .920 for total score for both the 26-item and 27-item tools. A confirmatory factor analysis was conducted for the convergent validity and discriminant validity. The standardized factor loadings to test the convergent validity showed more than .5(C.R<1.965) on all paths after deletion of item PC1 (avoid stairs). The average variances extracted were more than .50 and the construct reliabilities were more than .70. The average variances extracted were stronger than the squares of correlation coefficient of inter-latent variables. Conclusions: These results support that the $IWQOL-Kids^{(C)}$: Korean Version with a 26-item is a reliable and valid tool in Korean obese adolescents.

• The Journal of Korean Physical Therapy
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• v.30 no.6
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• pp.205-210
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• 2018

Purpose: This study was to examine the effects of treadmill gait training at different controlled inclinations on the standing balance of hemiplegic patients caused by cerebrovascular injury. Methods: The study's subjects were 44 patients with chronic stroke, randomly divided into three experimental groups: $0^{\circ}$ treadmill gait training (n=14), $5^{\circ}$ treadmill gait training (n=15), and $10^{\circ}$ treadmill gait training (n=15). In addition to conventional physical therapy, the subjects underwent gait training on a treadmill with one of three different inclinations for 30 min per session five times per week for six weeks. The Biodex balance system SD, Berg balance scale, and timed up and go tests were used to measure the postural balance of the patients. Results: This study showed that gait training on a treadmill at controlled inclinations of $0^{\circ}$, $5^{\circ}$, and $10^{\circ}$ positively influenced the stroke patients' standing balance. The $5^{\circ}$ and $10^{\circ}$ inclination gait training groups showed significantly more improvement than the $0^{\circ}$ inclination group. Conclusion: Gait training on a treadmill with inclinations of $0^{\circ}$, $5^{\circ}$, or $10^{\circ}$ can be said to positively affect the postural balance of hemiplegic patients due to stroke. In particular, $5^{\circ}$ and $10^{\circ}$ inclination gait training offered more significant improvement than the $0^{\circ}$ inclination gait training group. When added to regular treatment routines, gait training at controlled inclinations is an effective intervention for improving hemiplegia due to postural balance.

• Investigative Magnetic Resonance Imaging
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• v.25 no.2
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• pp.118-128
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• 2021

Purpose: To investigate the value of MR textural analysis, including use of diffusion-weighted imaging (DWI) to differentiate malignant from benign soft-tissue tumors on 3T MRI. Materials and Methods: We enrolled 69 patients (25 men, 44 women, ages 18 to 84 years) with pathologically confirmed soft-tissue tumors (29 benign, 40 malignant) who underwent pre-treatment 3T-MRI. We calculated MR texture, including mean, standard deviation (SD), skewness, kurtosis, mean of positive pixels (MPP), and entropy, according to different spatial-scale factors (SSF, 0, 2, 4, 6) on axial T1- and T2-weighted images (T1WI, T2WI), contrast-enhanced T1WI (CE-T1WI), high b-value DWI (800 sec/mm²), and apparent diffusion coefficient (ADC) map. We used the Mann-Whitney U test, logistic regression, and area under the receiver operating characteristic curve (AUC) for statistical analysis. Results: Malignant soft-tissue tumors had significantly lower mean values of DWI, ADC, T2WI and CE-T1WI, MPP of ADC, and CE-T1WI, but significantly higher kurtosis of DWI, T1WI, and CE-T1WI, and entropy of DWI, ADC, and T2WI than did benign tumors (P < 0.050). In multivariate logistic regression, the mean ADC value (SSF, 6) and kurtosis of CE-T1WI (SSF, 4) were independently associated with malignancy (P ≤ 0.009). A multivariate model of MR features worked well for diagnosis of malignant soft-tissue tumors (AUC, 0.909). Conclusion: Accurate diagnosis could be obtained using MR textural analysis with DWI and CE-T1WI in differentiating benign from malignant soft-tissue tumors.

• The Journal of the Convergence on Culture Technology
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• v.8 no.1
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• pp.121-129
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• 2022

This study explored effective teaching-learning activities under the hybrid teaching model combining flipped learning, direct instruction, cooperative learning and distance learning. Subjects were 99 college students enrolled in 2 teacher preparation courses. Students evaluated effectiveness of 22 teaching-learning activities according to Likert scale at the end of the semester. As a result, all 22 teaching learning activities were considered effective more or less. They facilitated motivation, comprehension, participation, thinking, and led to mastery of the task. ② Activities scored low were 'questioning and answering at the beginning of online class', 'open book test'. ③ Hybrid teaching model was favored over traditional instruction. Open ended responses were consistent with the ones in the questionnaire. This research supports the notion that key teaching models to be combined for successful flipped learning in college setting are direct instruction and cooperative learning. Furthermore, effective and ineffective teaching strategies for flipped learning were found.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.27 no.3
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• pp.1-15
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• 2021

Objective: The purpose of this study was to examine the differences in joint position sense (JPS), force sense (FS), and performance level of the upper extremities according to the injury and pain experiences of Korean elite archers. Methods: A total of 15 subjects were briefed about the purpose of this study and agreed to participate voluntarily. JPS was evaluated using the laser-point attached to the wrist while aiming at the target. The difference when relocating while aiming was used as JPS factor. FS was evaluated using load cell through reproduces same muscle strength. Fear-Avoidance Beliefs Questionnaire (FABQ) was used to evaluate psychosocial factors, Kerlan-Jobe Orthopedic Clinic overhead athlete scores (KJOC) and numerical rating scale (NRS) was used to evaluate pain. and performance was evaluated by tournament match score. Results: There is a strong correlation between the current pain and KJOC. Moreover, moderate correlation between KJOC and FABQ also current pain and both upper trapezius and lower trapezius in elite archers. The mean (SD) between groups based on current pain display relatively large margin in force sense than without pain group. The result presents that there is a significant difference in performance and pain. There is a significant difference in the force sense of the upper and lower trapezius and pain. Conclusions: Result present there is a significant difference in functional level in the average comparison between groups according to the presence of absence of current pain. There is a significant difference in the force sense of the upper trapezius as well as lower trapezius and without pain group present a relatively low joint position sense error compared to the groups.

• PNF and Movement
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• v.21 no.1
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• pp.1-10
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• 2023

Purpose: This systematic review aims to determine whether robot-assisted training is more effective in gait training for persons with subacute hemiparetic stroke. Methods: This study adopted a systematic review study design focused on subacute hemiparetic stroke, and four core academic databases were searched until June 11, 2021, for relevant studies, including PubMed, Embase, the Cochrane Library, and ProQuest Central. The review included randomized controlled trials (RCTs) evaluating the effects of robotic-assisted training on gait performance in persons with a diagnosis of subacute hemiparetic stroke. The selected RCT studies were qualitatively synthesized based on the population, intervention, comparison, outcome, settings, and study design (PICOS-SD). Results: The study selected five RCTs involving 253 subacute hemiparetic stroke patients and performing robotic-assisted gait training using the following devices: the Lokomat, Morning Walk, Walkbot, ProStep Plus, or Gait Trainer II. Five RCTs were eligible for the meta-analysis after quantitative synthesis, and the results showed that the robot-assisted gait training group had a greater gait performance than the control group based on the 10-meter walk test, Berg balance scale, Rivermed mobility index, functional ambulation category, and modified Barthel index. Conclusion: The results of this study showed that the gait performance of subacute hemiparetic stroke patients changes throughout robot-assisted gait training, but there were no indications that any of the clinically relevant effects of robot-assisted training are greater than those of conventional gait training. Further, the small sample size and different therapeutic intensities indicate that definitive conclusions could not be made.