• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2010.10a
• /
• pp.737-739
• /
• 2010

In this paper, the subthreshold characteristics have been alanyzed using MicroTec4.0 for double gate MOSFET(DGMOSFET). The technology for characteristic analysis of device for high integration is changing rapidly. Therefore to understand characteristics of high-integrated device by computer simulation and fabricate the device having such characteristics became one of very important subjects. The oxide thickness and channel thickness in DG MOSFET determines threshold voltage and extensively influences on Ss(Subthreshold swing). We have investigated the threshold voltage and Ss(Subthreshold swing) characteristics according to variation of channel thickness from 1nm to 3nm in this study.

• Korean Journal of Biological Psychiatry
• /
• v.22 no.1
• /
• pp.7-13
• /
• 2015

Objectives The purpose of this study was to examine the psychiatric characteristics of outpatients with tinnitus. Methods A total of 88 subjects were included in this study. According to Tinnitus Handicap Inventory (THI) scores, the subjects were classified into two group ; a mild tinnitus symptoms (mild-tinnitus) group and a severe tinnitus symptoms (severe-tinnitus) group. A questionnaire was used for an assessment of demographic characteristics, and the THI, the Visual Analogue Scale (VAS) about tinnitus, the Beck Depression Inventory (BDI), and the Beck Anxiety Inventory (BAI) are applied for evaluation of other clinical psychiatric characteristics. Results Higher THI scores were positively correlated with tinnitus course, the number of accompanying symptoms, and the VAS. BDI total scores, BDI factors, and BAI total scores were significantly higher in the severe-tinnitus group than in the mild-tinnitus group. Also suicidal ideation, interpersonal problems, sleep problems, occupational impairment, and fatigue were significantly higher in the severe-tinnitus group than in the mild-tinnitus group. Conclusions Tinnitus is a common disorder of hearing which is associated frequently with psychiatric problems. This study suggests that psychiatric interventions should be taken into consideration in the treatment of patients suffering from tinnitus.

• Journal of architectural history
• /
• v.13 no.3
• /
• pp.85-95
• /
• 2004

Through 16-17th century, Neo-Confucianism was accepted and extended to Chosun Dynasty. The architecture of the Taegae school made buildings of Yongnam area rich by adding the regional characteristics based on Taegae's thought of architecture. The following is the architectural characteristics of the academic clique around Sangju. Transformation such as separation and combination of the Jeongsa space by function, lifted floor type reflecting local feature or high platform was appeared, and the architectural characteristics of the Taegae school, that is, a small scale, a moderate figure, a type of side-attached floor, landscape, were still maintained at the same time. The characteristics of the Taegae school and regional figure of Sangju were well joined. The upper class houses, Seodang, Jeongsa and Seowon, built by Confucianist had shared common Confucian characteristics in spite of their different purposes. The world view of the Confucianism such as sacrifice for sages, cultivation, devoting for study, teaching disciples, and education for villagers was revealed through the Confucian architecture including dwelling houses during the 16-17th century. Buildings of Confucianist were focused on the space for men. Seoae and Kyumam built two different Jeongsa's inside and outside of the boundary of the nakdong river. While Seodang and Jeongsa located outside of the boundary of the river were built excluding spaces for living, the function of the Jeongsa located inside of the boundary of the river was assimilated by Sarangcahe. However, both buildings kept the function for cultivation, devoting for study and teaching.

• Journal of Korean society of Dental Hygiene
• /
• v.12 no.4
• /
• pp.741-749
• /
• 2012

Objectives : High school students to measure fear of dental treatment, dental health care workers according to the level of reliability of this study is to determine the extent of terror was carried out. Methods : Located in Gwangju, 165 high school students were surveyed. SPSS windows ver. 11.0 by demographic characteristics and oral health characteristics of the frequency and percentage, and dental health care workers about the reliability of the Chi-square test, the general characteristics and oral health characteristics by dental fear of the t-test and one way ANOVA and were factors associated with dental fear of the stepwise multiple regression analysis was performed. General characteristics, except Cronbach-${\alpha}$ coefficient was 0.911. Results : According the general fear of Dental Treatment Fear Factor item 4, you'll feel the highest fear when you feel the muscle tension and the needle pricks your skin. The reliability of dental health care workers if the dentist lower the higher the grade, subjective oral health status is considered more reliable health was higher, the stronger the reliability of pain was significantly lower (p<0.05). Other care coordination include the reliability of sources of interest in subjective oral health history, no past experience in treating pain and increase the number of reliability was low (p<0.05), past experience and increase the number of pain during treatment the stronger the fear of more pain showed an increase (p<0.05). Conclusion : According the related factors about the fear of dental treatment, stimulus-response and fear of dental office have increased, the fear of dental treatment increase.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.37 no.5
• /
• pp.25-32
• /
• 2000

In this paper, we consider the effects on the bandpass filter characteristics due to the phase variation of the inverters with frequency, which introduces the deviations of the bandpass filter characteristics from the design goals. In order to resolve these kinds of problems, we proposed novel inverter configurations. And we derived the inverter formulas for the proposed inverter configuration. By employing the proposed inverter configuration and the derived formulas, bandpass filters are designed and simulated. In order to show the validity of the proposed design method, the simulation characteristics are compared with design results by conventional design procedures. Compared results show the compensation of the deviations of bandpass filter characteristics without any optimization or iterative design procedures and additional calculation efforts.

• Journal of the Korea Convergence Society
• /
• v.8 no.6
• /
• pp.171-180
• /
• 2017

This study was executed to verify the effects of individual and environmental characteristics of secondary-school teachers on teacher efficacy and job satisfaction. To do so, a survey of teacher efficacy and job satisfaction was conducted to 696 man and woman teachers from 55 secondary schools in Gwangju and Jeonnam province, and then the results of the survey were analyzed. In this study, teacher efficacy was composed as four factors: sense of calling, teaching-learning, colleague relation and school organization. And job satisfaction was categorized as three factors: job relation, compensation system and working environment. The Multivariate analysis results showed a significant difference in teacher efficacy and job satisfaction according to teachers' individual characteristics and working environment. Conclusively, teacher efficacy and job satisfaction are complicated factors formed by teachers' individual and environmental characteristics. To improve secondary-school teachers' teacher efficacy and job satisfaction, it is necessary to develop training and education programs reflecting individual and environmental characteristics.

• Journal of Digital Convergence
• /
• v.19 no.12
• /
• pp.487-494
• /
• 2021

This study aims to find out how the leadership type of middle school soccer coach affects sport flow and team atmosphere, and the results are as follows. First, as a result of analyzing the demographic characteristics, it was found that there was a significant difference in the peer relationship characteristics of the team atmosphere by the variable of age, and the mutual leadership by the variable of life period with coach. Second, as a result of examining the influence of middle school soccer coach's leadership type on sport flow, it was found that among leadership types, servant leadership affected all sub-factors of sport flow and transformational leadership affected behavioral flow. Third, as a result of examining the effect of middle school soccer coach's leadership type on team atmosphere, it was found that all leadership types had an effect on the role characteristics, which are the sub-factors of team atmosphere, servant leadership on the peer relationship characteristics, and transactional leadership on the team characteristics.

• Oral Biology Research
• /
• v.42 no.4
• /
• pp.187-197
• /
• 2018

Chemical agents such as minocycline (MC) and citric acid (CA) were suggested in the treatment of contaminated implant surface. In this study, MC-HCl treatment was performed to enhance surface characteristics of titanium alloy surface. The purpose of this study was to assess the characteristics and the biocompatibility of Ti-6Al-4V surface treated by MC. Alpha-beta titanium alloy (Ti-6Al-4V) samples were prepared and they were divided into 6 groups according to chemical concentration and treatment time. These groups include 1) group I, non-treated smooth titanium alloy; 2) group II, MC 1.5 mg/mL for 1 hour; 3) group III, MC 1.5 mg/mL for 24 hours; 4) group IV, MC 15 mg/mL for 10 minutes; 5) group V, MC 100 mg/mL for 5 minutes; 6) group VI, pH1 CA for 3 minutes. The analysis of the surface characteristics of MC-treated titanium alloy was executed using scanning electron microscopy, roughness test, and X-ray photoelectron spectroscopy (XPS). Cell adhesion and MTT assay was done using MC3T3 cell. Titanium surfaces treated with MC indicated a more smoothened surface microstructure. For group II and III, the new peaks of rutile TiO2 were found. Group II and V have more basic group of Ti-OH form in XPS. In MTT assay, all MC-treated groups showed significantly higher cell viability compared to control. The surface roughness, crystal structure, surface hydrophilicity, cell viability of smooth titanium surface was improved by MC treatment. Compared with the control experiment and CA-treated group, smooth titanium surface treated with MC showed improved surface characteristics and cell biocompatibility.

• Tribology and Lubricants
• /
• v.36 no.6
• /
• pp.365-370
• /
• 2020

Recently, additive manufacturing (AM) technology has been applied to various industries such as automotive, aviation, medical, and electronics. Most prior studies are limited to the mechanical properties of printed materials, and few studies are being conducted on their tribological characteristics. However, the friction and wear characteristics of the material should be studied in order to utilize the components manufactured using AM technology as mechanical parts. In this study, the friction and wear characteristics of acrylonitrile-butadiene-styrene (ABS)-like resin printed with stereo lithography apparatus (SLA) 3D printing are evaluated according to the viscosity of silicon oil lubricant using a ball-on-disk experiment. Lubricants with a viscosity of 500, 1000, and 2000 cSt are prepared for the experiment. If silicon oil lubricants are used during the ball-on-disk test, the coefficient of friction (COF) and wear rates are significantly reduced, and the higher the viscosity of the lubricant, the lower will be the COF and wear rates. It is also verified that the temperature of the specimen owing to friction also decreases according to the viscosity of the lubricant. This is because of the silicon oil film thickness, and the higher the viscosity of the lubricant, the thicker will be the oil film. More studies on the tribological characteristics of 3D printing materials and suitable lubricants will be required to use 3D printed parts as mechanical elements.

• Smart Structures and Systems
• /
• v.33 no.2
• /
• pp.145-163
• /
• 2024

The evaluation of dynamic characteristics of bridges under operational traffic loads is a crucial aspect of bridge structural health monitoring. In the vehicle-bridge interaction (VBI) system, the vibration responses of bridge exhibit time-varying characteristics. To address this issue, an accurate time-frequency analysis method that combines the autoregressive power spectrum based empirical wavelet transform (AR-EWT) and local maximum synchrosqueezing transform (LMSST) is proposed to identify the time-varying instantaneous frequencies (IFs) of the bridge in the VBI system. The AR-EWT method decomposes the vibration response of the bridge into mono-component signals. Then, LMSST is employed to identify the IFs of each mono-component signal. The AR-EWT combined with the LMSST method (AR-EWT+LMSST) can resolve the problem that LMSST cannot effectively identify the multi-component signals with weak amplitude components. The proposed AR-EWT+LMSST method is compared with some advanced time-frequency analysis techniques such as synchrosqueezing transform (SST), synchroextracting transform (SET), and LMSST. The results demonstrate that the proposed AR-EWT+LMSST method can improve the accuracy of identified IFs. The effectiveness and applicability of the proposed method are validated through a multi-component signal, a VBI numerical model with a four-degree-of-freedom half-car, and a VBI model experiment. The effect of vehicle characteristics, vehicle speed, and road surface roughness on the identified IFs of bridge are investigated.