• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.1
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• pp.26-32
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• 1998

We have studied how the characteristics degradation between effective mobility and field effect mobility of gate channel in p-MOSFET's affects the gate channel length being follow by increased stress time and increased drain-source voltage stress. The experimental results between effective and field-effect mobility were analyzed that the measurement data are identical at the point of minimum slope in threshold voltage, the other part is different, that is, the effective mobility it the faster than the field-effect mobility. Also, It was found that the effective and field-effect mobility. Also, It was found that the effective and field-effect mobility of p-MOSFET's with short channel are increased by decreased channel length, increased stress time and increased drain-source voltage stress.

• Journal of Preventive Medicine and Public Health
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• v.34 no.2
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• pp.109-118
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• 2001

The purpose of this review is to discuss the debate concerning the interpretation of epidemiologic studies on particles and health effects. Study of the 1952 air pollution disaster in London established that very high levels of particulate-based smog can cause dramatic increases in daily mortality. However, recent epidemiologic studies have reported statistically significant health effects and mortality due to low levels of air pollution. The statistical significance does not prove causation in observational studies; therefore it is necessary to evaluate these associations. There are arguments for and against each of the numerous studies using Hill's criteria, however the body of accepted evidence supports the causal association. In particular, a high level of consistency in the estimated effect of PM10 has been observed across studies worldwide. The mechanism of the relationship between air pollution and health effects is not obvious. The mechanism of particle-induced injury may involve the production of an inflammatory response by the particulate. The harvesting and the threshold effect are also major concerns regarding the health effects of air pollution. However, current epidemiologic findings indicate that linear models lacking a threshold are appropriate for assessing the effect of particulate air pollution on daily mortality even at current levels.

• Applied Chemistry for Engineering
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• v.22 no.5
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• pp.551-554
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• 2011

One of the key issues in the research of organic field-effect transistors (OFETs) is the low-voltage operation. To address this issue, we synthesized poly(styrene-r-benzocyclobutene-r-methyl methacrylate) (P(S-r-BCB-r-MMA)) as a thermally cross-linkable gate dielectrics. The P(S-r-BCB-r-MMA) showed high quality dielectric properties due to the negligible volume change during the cross-linking. The pentacene FETs based on the 34 nm-thick P(S-r-BCB-r-MMA) gate dielectrics operate below 5 V. The P(S-r-BCB-r-MMA) gate dielectrics yielded high device performance, i.e. a field-effect mobility of $0.25cm^2/Vs$, a threshold voltage of -2 V, an sub-threshold slope of 400 mV/decade, and an on/off current ratio of ${\sim}10^5$. The thermally cross-linkable P(S-r-BCB-r-MMA) will provide an attractive candidate for solution-processable gate dielectrics for low-voltage OFETs.

• Journal of IKEEE
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• v.27 no.4
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• pp.644-649
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• 2023

As the cell spacing decreases during the scaling process of DRAM(Dynamic Random Access Memory), the reduction in STI(Shallow Trench Isolation) thickness leads to an increase in sub-threshold leakage due to the passing word line effect. The increase in sub-threshold leakage current caused by the voltage applied to adjacent passing word lines affects the data retention time and increases the number of refresh operations, thereby contributing to higher power consumption in DRAM. In this paper, we identify the causes of the passing word line effect through TCAD Simulation. As a result, we confirm the DRAM operational conditions under which the passing word line effect occurs, and observe that this effect alters the proportion of the total leakage current attributable to different causes. Through this, we recognize the necessity to consider not only leakage currents due to GIDL(Gate Induced Drain Leakage) but also sub-threshold leakage currents, providing guidance for improving DRAM structure.

• Weed & Turfgrass Science
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• v.1 no.4
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• pp.13-17
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• 2012

A field experiment was conducted to investigate the effect of Acalypha australis occurrence on the growth and yield of soybean, to predict the reduction rate of soybean yield caused by competing with A. australis and to establish the economic threshold of A. australis for soybean cultivation. As the density of A. australis increase, the height and stem length of soybean were not affected by the competition with A. australis, however, the yield of soybean was decreased as 11~51% as compared with weed-free condition. The relationship between weed density and soybean yield was established as Y=415.5 / (1+0.003356X) and the reduction rate of soybean yield were predicted from this equation. Compared with the weed-free condition, the reduction rate of soybean yield were calculated as 0.3~9%, 17~29%, and 40~46% when the density of A. australis were 1~30, 60~120, and 200~250 plants $m^{-2}$, respectively. The economic threshold level of A. australis for soybean cultivation was established as 6.3 plants $m^{-2}$ from the Cousens' equation.

• Journal of The Korean Society of Integrative Medicine
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• v.8 no.4
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• pp.223-230
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• 2020

Purpose : The purpose of this study was to examine the effects of tools (i., extracorporeal shock wave therapy, massage gun, and foam roller) on range of motion, muscle tone and pain threshold among patients with hamstring stiffness. Methods : Fourteen participants with hamstrings stiffness were recruited. Interventions were performed 6 times, and each session was for 30 seconds using the three tools. The range of motion, muscle tone, and pain threshold were measured. The order of the use of the three tools was randomly determined. The foam roller was made to move from the bottom of the hip crease to the upper part of the back of the hamstring. Additionally, velocity 5 vibration stimulation was performed on the hamstring using a massage gun. Moreover, vibration stimulation was performed on the hamstring with extracorporeal shock wave therapy 5 minutes, 5 Hz, and 1,500 strokes. The flexibility of the posterior thigh muscle was based on maintaining the knee and hip joints in a 90 ° bend in the supine position. The joint angle of the knee was measured, when the knee was actively extended, at the maximum point where the posterior thigh muscle was stretched. The elasticity of the posterior thigh muscle was measured while the subject was prone and in a relaxed state without any force. Measurements were made at the muscle abdominal area of the semitendinosus muscle of the posterior femur, and the area to be measured was marked with a pen. The measurement of the tenderness threshold of the posterior femur was measured using a tenderness meter(Commander Algometer, J-Tech, USA). The force value at the point at which the pressure sensation change to pain was measured after applying vertical pressure to the posterior femur muscle, which was the halfway point between the ischial tuberosity and the popliteal surface of the subject lying on their stomach. Results : The extracorporeal shock wave therapy increased stiffness and, muscle tone, and caused changes in the pain threshold, whereas the other two tools had no effect on these indices. Conclusion : Extracorporeal shock wave therapy has important effects on range of motion and muscle stiffness and can be used in warmup protocols.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.5
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• pp.537-542
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• 2014

The three-dimensional (3-D) NAND flash structure with fully charge storage using edge fringing field effect is presented, and its programming characteristic is evaluated. We successfully confirmed that this structure using fringing field effect provides good program characteristics showing sufficient threshold voltage ($V_T$) margin by technology computer-aided design (TCAD) simulation. From the simulation results, we expect that program speed characteristics of proposed structure have competitive compared to other 3D NAND flash structure. Moreover, it is estimated that this structural feature using edge fringing field effect gives better design scalability compared to the conventional 3D NAND flash structures by scaling of the hole size for the vertical channel. As a result, the proposed structure is one of the candidates of Terabit 3D vertical NAND flash cell with lower bit cost and design scalability.

• Geomechanics and Engineering
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• v.32 no.5
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• pp.495-502
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• 2023

In this study, stress relaxation tests were carried out by keeping silt type soil specimens under different strain levels. Decreases in the stress values with time data was collected to better understand the effect of the strain level on the relaxation properties of soil specimens. In addition, the stress relaxation effect on the uniaxial compressive strength (UCS) values of the specimens was investigated with a series of tests. According to the results obtained from this study, the UCS values of the silt specimens significantly vary as a result of the stress relaxation effect. The UCS values were determined to increase with an increase of relaxation strain level to a threshold value. On the other hand, the UCS values were found to be affected adversely in case of high stress levels at the initiation of the relaxation, which are close to the peak level.

• Journal of Oral Medicine and Pain
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• v.36 no.1
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• pp.1-10
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• 2011

The aims of this study were to establish the effect of gender and age on number of fungiform papillae and electrogustometric thresholds of the tongue, and to determine the relation between number of fungiform papillae and electrogustometric threshold. Sixty-two healthy subjects of 20 to 39 years old were enrolled in this study. Examination areas were defined as center, anterior, left lateral, right lateral, and posterior on the dorsal surface of the tongue, which was stained with methylene blue dye and photographed with a scale bar on it. The number of fungiform papillae within $1\; cm^2$ square area of each examination site was counted twice. The counted values were averaged to produce means. Taste thresholds were measured three times on each examination area using an electrogustometer. Means of the threshold values were calculated. 1. The number of fungiform papillae was the largest at the anterior examination area, followed by right lateral, left lateral, posterior and central. Women had more fungiform papillae than men at anterior, right lateral, and center areas. Subjects in twenties showed more fungiform papillae than those in thirties at anterior, right lateral, and left lateral areas. 2. Anterior area of the tongue measured the lowest electrogustometric threshold, followed by left lateral, right lateral, posterior and center. The threshold was higher in men at anterior and right lateral areas. The subjects in thirties had higher threshold only at right lateral area than those in twenties. 3. Electrogustometric threshold was inversely correlated with the number of fungiform papillae at anterior and posterior areas. The results showed that the number of fungiform papillae and taste threshold varied according to tongue locus, and they were influenced by age and gender. The results also suggested that the number of fungiform papillae was related to electrogustometric threshold inversely.

• Journal of Food Hygiene and Safety
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• v.21 no.1
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• pp.9-13
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• 2006

In this study the expression of the sweetness by using threshold value and effects of salt addition on the sweetness was carried out in model system. Threshold value was 0.4% in sucrose solution and was 0.75-0.80% in the mixture of sweeteners such as low glutinous starch syrup and reduced starch syrup with sucrose solution. The equation between mixture of sweeteners and relative sweetness ($0-20^{\circ}Brix$) on sucrose was induced. The sweetness of red bean paste prepared with low glutinous starch syrup and reduced starch syrup were estimated as 32.78-34.32 by using threshold value, and those lower than 55 of red bean paste prepared with sucrose alone. The synergistic effect of sweetness was observed when 0.05% salt in sugar solution (2.0%) and 0.2% salt in red bean paste were added, respectively. It showed that the addition of salt could be increase the degree of sweetness and decrease the quantity of sweeteners.