• Proceedings of the IEEK Conference
• /
• 2003.07b
• /
• pp.691-694
• /
• 2003

Density gradient method is used to analyze the quantum effect in MOSFET, Quantization effect in the poly gate leads to a negative threshold voltage shift, which is opposed to the positive shift caused by quantization effect in the channel. Quantization effects in the poly gate are investigated using the density gradient method, and the impact on the short channel effect of double gate device is more significant.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.4 no.1
• /
• pp.27-31
• /
• 2004

Models and simulations of gate tunneling current for thinoxide MOSFETs and Double-Gate SOIs are discussed. A guideline in design of leaky MOS capacitors is proposed and resonant gate tunneling current in DG SOI simulated based on quantum-mechanicalmodels. Gate tunneling current in fully-depleted, double-gate SOI MOSFETs is characterized based on quantum-mechanical principles. The simulated $I_G-V_G$ of double-gate SOI has negative differential resistance like that of the resonant tunnel diodes.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.18 no.2 s.117
• /
• pp.118-125
• /
• 2007

Harmonic band of bandpass filter(BPF) is suppressed using coupled mushroom structure. Between double positive (DPS) transmission line such as microstrip and double negative(DNG) transmission line such as one dimensional mushroom structure, strong coupling broadly arises in the cross range of dispersion curves of isolated microstrip and mushroom structure because of complex propagation constant in the cross range. Strong coupling inhibits wave propagation, so that this kind of structure can be utilized as bandstop filter(BSF). This BSF utilizes coupled transmission line instead of coupled resonator, resulting in broad bandwidth(>30 %), shan-rejection, and high rejection level. The strong coupling between DPS and DNG transmissionline makes it possible shorten coupling length, resulting in compact size. In this paper, parallel coupled BSF having center frequency of 4 GHz and 3 dB fractional bandwidth of 40 % is designed and utilized to suppressed spurious mode of two bandpass filters.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.14 no.3
• /
• pp.1266-1273
• /
• 2013

The purpose of this study was to analysis the effect of form of outsole - complex function double rocker sole(CDR) vs. negative-heel rocker sole (NR) - on energy consumption and heart rate intensity during gait. 11 women, who had no medical history on musculoskeletal disease and surgery within 3 years prior to study, were participated. The walking energy cost per time (WECt) during 35minutes, heart rate intensity, and total calorie consumption were compared by using pair t-test. The WECt and total calorie consumption were found to be significantly higher(p<.05) in CDR than NR. However, there was no difference in HRi. Based on the present study, CDR shoe may have significant implications in shoe prescription for people who want to increase energy consumption.

• Journal of Korean Society of Steel Construction
• /
• v.19 no.6
• /
• pp.681-693
• /
• 2007

Construction techniques for continuous steel bridges were applied to steel-concrete double composite box girder bridges. Concrete depth and length at the bottom of the steel box in the negative moment region were determined by plastic moment region and negative moment region of the double composite section, respectively. Construction methods, such as crane lifting method, free cantilever method, and incremental launching method were used for the analysis of the construction stage. Two cases of the construction phase were considered and analyzed for the stress resultant of double composite girders. The behavior of the nose-deck elastic system was examined by three-dimensionless parameters, such as the nose length, the unit weight of the launching nose, and the flexural stiffness of the nose. The adoption of the launching nose has become an effective solution in the incremental launching of steel-concrete double composite box girder bridges.

• Human Ecology Research
• /
• v.56 no.4
• /
• pp.377-390
• /
• 2018

This study examined the double mediating effects of work-family conflict and parenting guilt on the relationship between perfectionism and parenting behavior for working mothers. The survey was conducted on 340 working mothers with 3 to 5 year-old children, who lived in Daegu and Kyungpook Province, Korea. Data were collected through questionnaires on perfectionism, work-family conflict, parenting guilt, and parenting behavior. To analyze the collected data, descriptive statistics, factor analysis, and analysis of variance were conducted by using SPSS 22.0 and Model 6 in PROCESS macro, with bootstrapping method. Work-family conflict and parenting guilt were used as mediators. Children's birth order and household income were controlled throughout the analysis. The major findings of this study were as follows. First, work-family conflict and parenting guilt had inconsistent double mediating effects on the relationship between adaptive perfectionism and positive parenting behavior. Second, work-family conflict and parenting guilt had complete double mediating effects on the relationship between adaptive perfectionism and negative parenting behavior. Third, work-family conflict and parenting guilt did not have double mediating effects on the relationship between maladaptive perfectionism and positive parenting behavior. Finally, work-family conflict and parenting guilt had partial double mediating effects on the relationship between maladaptive perfectionism and negative parenting behavior. The findings provide a better understanding of the relationship between perfectionism and parenting behavior. The results also have implications for providing education for and counseling working mothers with children.

• Korean Journal of Applied Biomechanics
• /
• v.29 no.4
• /
• pp.255-261
• /
• 2019

Objective: The purpose of this study was to investigate differences of shock attenuation strategies between double-leg and single-leg landing on sagittal plane using statistical parametric mapping. Method: Nine healthy female professional soccer players (age: 24.0±2.5 yrs, height: 164.9±3.3 cm, weight: 55.7±6.6 kg, career: 11.2±1.4 yrs) were participated in this study. The subjects performed 10 times of double-leg and single-leg landing from the box of 30 cm height onto force plates respectively. The ground reaction force, angle, moment, angular velocity, and power of the ankle, knee, and hip joint on sagittal plane was calculated from initial contact to maximum knee flexion during landing phase. Statistical parametric mapping was used to compare the biomechanical variables of double-leg and single-leg landing of the dominant leg throughout the landing phase. Each mean difference of variables was analyzed using a paired t-test and alpha level was set to 0.05. Results: For the biomechanical variables, significantly increased vertical ground reaction force, plantarflexion moment of the ankle joint, negative ankle joint power and extension moment of the hip joint were found in single-leg landing compared to double-leg landing (p<.05). In addition, the flexion angle and angular velocity of the knee and hip joint in double-leg landing were observed significantly greater than single-leg landing, respectively (p<.05). Conclusion: These findings suggested that negative joint power and plantarflexion moment of the ankle joint can contribute to shock absorption during single-leg landing and may be the factors for preventing the musculoskeletal injuries of the lower extremity by an external force.

• Korean Journal of Cognitive Science
• /
• v.21 no.4
• /
• pp.535-557
• /
• 2010

Researchers have shown the negative compatibility effect (NCE) consistently using arrows. However, they provided inconsistent interpretations about the reason why the NCE happens. The purpose of the present study is to test the factors suggested to be critical for the NCE including automatic inhibition, updated information and top-down control. Presented with arrays of masked prime and targets composed of colored double-headed arrows, participants demonstrated invulnerable NCE on the basis of direction of arrows in the judgment of direction with corresponding hands (Experiment 1), with reverse-mapping hands (Experiment 2) and even in the color-judgment task (Experiment 3). These results imply that the main sources of NCE might be perceptual dominance and inherent properties of stimuli and responses; this contrasts with previously proposed explanations.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.27 no.4
• /
• pp.283-290
• /
• 2022

This study proposes a voltage control scheme in a synchronous reference frame to improve the dynamic characteristics of double-conversion UPSs. UPSs need to control positive and negative sequence voltage, so that positive and negative sequence extractors are generally used to obtain each sequence of the voltage and current. Voltage and current controllers for each sequence are implemented. However, the extractor causes considerable delay, and the delay restricts the control performance, especially for the current controller. To improve the dynamics of the current controller, the proposed scheme adopts a unified current controller without separating positive and negative sequences. By using discrete-time current controller, the control bandwidth can be extended significantly so that negative sequence current can be controlled. To enhance the performance, an additional feed-forward technique for output voltage regulation is proposed. The validity of the proposed controller is verified by experiments.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2000.11a
• /
• pp.133-136
• /
• 2000

We investigated the improvement of viewing angle using a patterned double twisted (PDT) vertical-alignment (VA) cell mode on a homeotropic alignment layer. Good voltage-transmittance curves for negative dielectric anisotropic nematic liquid crystal (NLC) using the PDT-VA cell without a negative compensation film were obtained. The viewing angle of the PDT-VA cell without a negative compensation film was wider than that of a conventional VA cell.