• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2014.05a
• /
• pp.755-758
• /
• 2014

This paper has analyzed the change of threshold voltage for oxide structure of symmetric and asymmetric double gate(DG) MOSFET. The asymmetric DGMOSFET can be fabricated with different top and bottom gate oxide thickness, while the symmetric DGMOSFET has the same top and bottom gate oxide thickness. Therefore optimum threshold voltage is considered for top and bottom gate oxide thickness of asymmetric DGMOSFET, compared with the threshold voltage of symmetric DGMOSFET. To obtain the threshold voltage, the analytical potential distribution is derived from Possion's equation, and Gaussian distribution function is used as doping profile. We investigate for bottom gate voltage, channel length and thickness, and doping concentration how top and bottom gate oxide thickness influences on threshold voltage using this threshold voltage model. As a result, threshold voltage is greatly changed for oxide thickness, and we know the changing trend very differs with bottom gate voltage, channel length and thickness, and doping concentration.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.10 no.1
• /
• pp.61-65
• /
• 2010

Threshold voltage is one of the most important factors in a device modeling. In this paper, analytical method to calculate threshold voltage for recessed channel (RC) MOSFETs is studied. If we know the fundamental parameter of device, such as radius, oxide thickness and doping concentration, threshold voltage can be obtained easily by using this model. The model predicts the threshold voltage which is the result of 2D numerical device simulation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2012.05a
• /
• pp.731-733
• /
• 2012

Because the Double gate MOSFET has two gates, it has more efficient on controling current than the exisiting MOSFET, and it can also decrease short channel effects in the nano-device. In this study, during the manufacturing the Double gate MOSFET, we will analyze the change of threshold voltage according to doping concentration that makes a significant impact on short channel effects. One of the structural factors that affect the threshold voltage on the Double gate MOSFET is the doping concentration, and it is very important device parameter. In this paper, we can find that the threshold voltage became larger when the doping concentration increased from $10^{15}cm^{-3}$ to $10^{19}cm^{-3}$.

• Journal of Community Nutrition
• /
• v.8 no.2
• /
• pp.107-113
• /
• 2006

Sensory factors are important determinants of appetite and food choices but little is known about factors affecting taste acuity and preference of Koreans. Any factors causing deficits in sweet taste perception may lead to over consumption of simple sugar, which is related to several chronic diseases. This study was conducted to determine factors affecting sweet taste sensitivity and preference. Subjects were 30 government employees who were serving as school dietitians or in the area of public health while they were studying in the program for the qualification to become nutrition teachers. Sweet taste threshold and the optimally-preferred sweetness of omija jelly were determined by a sensory evaluation and general characteristics, health-related lifestyles, dietary habits and food preferences were determined using a self-administered questionnaire. For the subjects of this study, detection threshold concentration of sucrose solution was $0.184{\pm}0.06%$ and optimally-preferred sucrose concentration of omija jelly was $13.88{\pm}2.28%$ and there was no significant correlation between the sweet taste sensitivity and preference. Subjects who had higher(${\ge}4$ out of 10) physical or psychological stress and who had late getting-up time (after 7am) tended to have lower sweet taste threshold (higher sensitivity) than their counterpart. The sweet taste preference determined by optimally-preferred sucrose concentration of omija jelly tended to be lower in the subjects who eat slowly. Those who answered in the questionnaire to prefer sweet foods did have significantly higher optimally-preferred sucrose concentration of omija jelly. Further research is required to determine whether decreased sensitivity and increased preference for sweetness can increase the actual intake of simple sugar. (J Community Nutrition 8(2): 107 -113, 2006)

• The Transactions of the Korean Institute of Electrical Engineers C
• /
• v.51 no.11
• /
• pp.517-525
• /
• 2002

The channel region of seep-sub-micrometer MOSFET is non-uniformly doped with pocket implant. Therefore, the advanced threshold voltage model is needed to account for the Short-Channel Effect and Reverse-Short-Channel Effect due to the non-uniform doping concentration in the channel region. In this paper, A scalable analytical model for the MOSFET threshold voltage is developed. The developed model is verified with MEDICI and TSUPREM simulator.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2022.10a
• /
• pp.121-122
• /
• 2022

In this paper, the device performance with the structure of Nanosheet FET (NSFET) and FinFET is simulated through a three-dimensional device simulator. Current-voltage characteristics of NSFET and FinFET were simulated with respect to channel doping concentrations, and the performance such as threshold voltage and subthreshold swing extracted from the current-voltage characteristics was compared. NSFET flows more drain current and has a higher threshold voltage in current-voltage characteristics depending on channel doping concentration than that of FinFET. The subthreshold voltage swing (SS) of NSFET is steeper than that of FinFET

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2023.05a
• /
• pp.33-34
• /
• 2023

Corrosion of reinforcement steel is a major cause of deterioration in reinforced concrete (RC) structures. In order to protect these structures from corrosion, corrosion inhibitors are added to the concrete mix. In recent years, zwitterionic compounds have shown promising results as corrosion inhibitors in concrete due to their ability to form a protective layer on the surface of the reinforcement steel. The experimental study involves preparing concrete samples with different concentrations of adding the hybrid corrosion inhibitor at a high concentration of chloride ions. This study aims to determine the chloride threshold value and service life of hybrid corrosion inhibitors in reinforced concrete based on zwitterions. The samples are subjected to accelerated corrosion tests in a chloride environment to determine the threshold value and service life of the corrosion inhibitor. The effect of hybrid inhibitor on mechanical properties is guaranteed in allowable range. The chloride threshold concentration and service life of hybrid inhibitor containing samples perform greater than those of plain RC.

• Journal of Nutrition and Health
• /
• v.38 no.1
• /
• pp.76-81
• /
• 2005

The effects of the amount of red pepper intake per a day on the capsaicin threshold, nutrient intake, and anthropo-metric measurements were investigated in 100 female students of university. Three 24-hour recalls were performed to estimate usual nutrient and red pepper intake of free-living participants. The solutions containing capsaicin at concentration of 0.05, 0.1, 0.2, 0.3, 0.4, 0.5ppm used for the evaluation of hot-taste detection threshold. Subjects were asked to recognize the burning sensation after tasting l0ml of each test solution in ascending order of capsaicin concentrations. Mean intake of red pepper was 4.6 g/d and the capsaicin threshold was 0.27 ppm. The detection threshold for capsaicin was correlated with the amount of pepper intake per a day. Red pepper intake was correlated with energy, protein, lipid, carbohydrate, Iron, vitamin A, vitamin B$_2$ niacin, and vitamin E intakes. However, it was not correlated with intake of calcium, vitamin B$_1$ or vitamin C. The red pepper intake was negatively correlated with fat mass and waist girth and the capsaicin threshold was also negatively correlated with pulse. In conclusion, red pepper intake was associated with nutrient intake and capsaicin threshold whereas it was negatively correlated with fat mass and waist girth.

• The Korean Journal of Food And Nutrition
• /
• v.30 no.2
• /
• pp.257-268
• /
• 2017

The purpose of this research was to evaluate the correlation between obesity, threshold of salty taste, optimal saltiness and blood pressure in middle school students in a fishing village. The subjects were 115 boys and 103 girls in middle school in a fishing village. The BMI index and systolic and diastolic blood pressures of subjects were measured, and the subjects were divided into a normal and obese group according to their BMI. The threshold of salty taste and salt preference for a semisolid dish (steamed egg dish), liquid dish (bean sprout soup), and a solid dish (raw radish salad), were estimated by sensory evaluation. Calorie intake was measured using the weighing plate method. The boys in the obese group showed significantly higher systolic and diastolic blood pressures than those in the normal, but girls did not. Furthermore, calorie intakes of the boys in the obese group were significantly higher than those in the normal group, but this was not shown in girls. On the threshold of salty taste, both boys and girls in the obese group needed higher concentration of salt than those in the normal group. The threshold of salty taste were significantly positively correlated with systolic pressure and diastolic pressure in boys. Regarding the salt preference in the steamed egg dish, bean-sprout soup, and raw radish salad, both boys and girls in the obese group preferred higher concentrations. The higher concentration they preferred, the higher the systolic and diastolic pressures were in boys, but only systolic blood pressure was higher in girls. From these results, it is evident that a nutritional education program is needed in school to help restricting middle school students salt consumption and decreasing obesity to prevent hypertension.

• Journal of Soil and Groundwater Environment
• /
• v.22 no.1
• /
• pp.49-58
• /
• 2017

Biotic ligand model (BLM) and species sensitivity distribution (SSD) were used to determine the site-specific Cu threshold concentration (5% hazardous concentration; HC5) in soil pore water. Model parameters for Cu-BLM were collected for six plants, one collembola, and two earthworms from published literatures. Half maximal effective concentration ($EC_{50}\{Cu^{2+}\}$), expressed as $Cu^{2+}$ activity, was calculated based on activities of major cations and the collected Cu-BLM parameters. The $EC_{50}\{Cu^{2+}\}$ varied from 2 nM to $251{\mu}M$ according to the variation in environmental factors of soil pore water (pH, major cation/anion concentrations) and the type of species. Hazardous activity for 5% (HA5) and HC5 calculated from SSD varied from 0.076 to $0.4{\mu}g/L$ and 0.4 to $83.4{\mu}g/L$, respectively. HA5 and HC5 significantly decreased with the increase in pH in the region with pH less than 7 due to the decrease in competition with $H^+$ and $Cu^{2+}$. In the region with pH more than 7, HC5 increased with the increase in pH due to the formation of complexes of Cu with inorganic ligands. In the presence of dissolved organic carbon (DOC), Cu and DOC form a complex, which decreases $Cu^{2+}$ activity in soil pore water, resulting in up to 292-fold increase in HC5 from 0.48 to $140{\mu}g/L$.