• The Korean Journal of Pain
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• v.12 no.2
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• pp.195-199
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• 1999

Background: At present, there is no reliable objective test for the diagnosis of myofascial trigger points (MFTP). We evaluated the usefulness of skin resistance point finder for the diagnosis of MFTP. Methods: 40 subjects with clinical MFTPs at the upper trapezius muscle were included in this study. Using skin resistance point finder (UNIQUE S-2010$^{(R)}$, Seik medical, Korea), we tried to find out the point of low skin resistance. At three different current level, sensitivity and specificity of this method for the diagnosis of clinically identified MFTP was evaluated. Pressure threshold for pain of low skin resistance point was measured using Pressure Threshold Meter$^{(R)}$ (Pain Diagnostics and Thermography, U.S.A.). 3 groups of point detected at different current were compared in mean pressure threshold. Results: Fixed single current of skin resistance point finder showed variable sensitivity and specificity. But, by adjusting current level, skin resistance point finder detected all of 40 clinically identified MFTPs. Although it is partially statistically significant, the mean pressure threshold of points detected at high current was high. Conclusion: Skin resistance finder can be used as objective diagnostic tool of MFTPs. There is possibility that it can be useful in evaluating treatment effect. However, more investigation is necessary.

• The Journal of Korean Physical Therapy
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• v.25 no.2
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• pp.76-80
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• 2013

Purpose: The objective of this study was to offer primary clinical data examining whether change of imaging structure and quantitative evaluation of muscle activity on myofascial trigger points can lead to implementation of an analytical technique for evaluation of myofascial pain diagnoses. In addition, we examined the effect of a variety of mediation techniques, in order to examine neuromuscular physiological characteristics of myofascial trigger points muscle by comparing differences in pressure pain threshold and ultrasound imaging. Methods: Participants in the study included 30 adults in their twenties. The subjects were divided into the normal and myofascial trigger points groups. Clinical outcomes were evaluated by pressure pain threshold for pain and ultrasound imaging was performed for evaluation of the structural characteristics of muscle. Independent t-test was used for statistical analysis. Results: The two groups showed statistical significance in the change in pressure pain threshold (p<0.05). Findings of ultrasound imaging analysis showed no significant differences, increased muscle thickness was observed (p>0.05). Findings of ultrasound imaging analysis showed significant differences, increased muscle echodensity was observed (p<0.05). Findings on ultrasound imaging analysis showed significant differences, increased muscle white area index was observed (p<0.05). Conclusion: From these results, active myofascial trigger points muscle showed quality deterioration on ultrasound imaging. Thorough evaluation of imaging structure and physiological characteristics can be useful quantitative analytical techniques for diagnosis of myofascial pain syndrome and a primary factor reflected in physical therapy intervention.

• JSTS:Journal of Semiconductor Technology and Science
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• v.13 no.4
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• pp.367-380
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• 2013

In this paper, an analytical threshold voltage model is developed for a short-channel double-material-gate (DMG) strained-silicon (s-Si) on silicon-germanium ($Si_{1-X}Ge_X$) MOSFET structure. The proposed threshold voltage model is based on the so called virtual-cathode potential formulation. The virtual-cathode potential is taken as minimum channel potential along the transverse direction of the channel and is derived from two-dimensional (2D) potential distribution of channel region. The 2D channel potential is formulated by solving the 2D Poisson's equation with suitable boundary conditions in both the strained-Si layer and relaxed $Si_{1-X}Ge_X$ layer. The effects of a number of device parameters like the Ge mole fraction, Si film thickness and gate-length ratio have been considered on threshold voltage. Further, the drain induced barrier lowering (DIBL) has also been analyzed for gate-length ratio and amount of strain variations. The validity of the present 2D analytical model is verified with ATLAS$^{TM}$, a 2D device simulator from Silvaco Inc.

• Journal of the Korean Society for Railway
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• v.13 no.5
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• pp.504-508
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• 2010

The development of high voltage Insulated Gate Bipolar Transistor (IGBT) have given new device advantage in the areas where they compete with conventional GTO (Gate Turnoff Thyristor) technology. The IGBT combines the advantages of a power MOSFET (Metal-Oxide Semiconductor Field-Effect Transistor) and a bipolar power transistor. The change of electrical characteristics for IGBT is mainly coming from the change of characteristics of MOSFET at the input gate and the PNP transistors at the output. The change of threshold voltage, which is one of the important design parameters, is brought by charge trapping at the gate oxide under the environment that radiation exists. The energy loss will be also studied as the inductance values are changed. In this paper, the electrical characteristics are simulated by SPICE, and compared for variation of inductance and threshold voltage based on IGBT.

• Journal of Nutrition and Health
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• v.30 no.8
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• pp.995-1008
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• 1997

This study was performed to investigate the change in taste perception during aging and its effects on dietary intake in Korean elderly. The subjects were female aged 65 through 90 in the Anyang area, and college women were included as a comparison group . Dietary intake of the elderly(n=155) and young subjects (n=38) was measured by a 3 day diet record. The taste threshold and 'just right' concentrations(JRC) for sweet and salty tastes were assessed by sensory evaluation . Sucrose solution (0.0.,0.4,0.6,0.8,1.0, 1.2%) and salt solution(0, 0.02, 0.03,0.06,0.09,0.12,0.15%) were used to establish thresholds. for JRC assessment, four suprathreshold sucrose concentrations of 5, 8, 11 and 14% in orange-pineapple flavored juice and salt concentrations of 0.20, 0.34, 0.50and 0.75% in beef stock were prepared. Mean intakes of energy, protein , vitamin A, thiamin , riboflavin, niacin ,calcium and iron of the elderly were below the Korean Recommended Dietary allowances. The elderly showed higher taste thresholds than young subjects of both sweet and salty tastes consumed less calories. Needs to bespecified. The older subjects having high threshold or JRCs for sweet and salty tastes consumed fewer calories from protein and fat. Pearson correlation coefficients was between JRC for sweet and salty tastes 0.54(p<0.01). The correlation coefficients between tastes threshold and nutrient intakes were very low for both age groups. Unlike the college women, in the elderly the JRC of sweet taste of the orange-pineapple juice were negatively correlated with intakes of energy, protein, fats, thiamin , riboflavin , niacin ,vitamin C , iron and consumption of meat and egg food groups (p<0.01). In summation age-related alterations in sweet and salty taste perception were observed in the elderly and dietary intakes of the elderly see to be influenced by these taste perception changes.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.10
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• pp.1049-1055
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• 2004

Chemical Mechanical Polishing (CMP) is referred to as a three body tribological system, because it includes two solids in relative motion and the CMP slurry. On the assumption that the abrasives between the pad and the wafer could be a major reason not only for the friction force but also for material removal during polishing, the friction force generated during CMP process was investigated with the change of abrasive size and concentration of CMP slurry. The threshold point of average coefficient of friction (COF) with increase in abrasives concentration during interlayer dielectric (ILD) CMP was found experimentally and verified mathematically based on contact mechanics. The predictable models, Mode I (wafer is in contact with abrasives and pad) and Mode II (wafer is in contact with abrasives only), were proposed and used to explain the threshold point. The average COF value increased in the low abrasives concentration region which might be explained by Mode I. In contrast the average COF value decreased at high abrasives concentration which might be regarded to as Mode II. The threshold point observed seemed to be due to the transition from Mode I to Mode II. The tendency of threshold point with the variation of abrasive size was studied. The increase of particle radius could cause contact status to reach transition area faster. The correlation between COF and material removal rate was also investigated from the tribological and energetic point of view. Due to the energy loss by vibration of polishing equipment, COF value is not proportional to the material removal rate in this experiment.

• Journal of Sensor Science and Technology
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• v.8 no.2
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• pp.95-101
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• 1999

When a metal oxide field effect transistor (MOSFET) is exposed to ionizing radiation, electron/hole pairs are generated in its oxide layer. The slow moving holes of them are trapped in the oxide layer of p-MOSFET and appear as extra charges that change the characteristics of the transistor. The radiation-induced charges directly impact the threshold (turn-on) voltage of the transistor. This paper describes the use of the radiation-induced threshold voltage change as an accumulated radiation dose monitoring sensor. Two kinds of commercial p-type MOSFETS were tested in a Co-60 gamma irradiation facility to see their capabilities as a radiation dosimeter. We found that the transistors showed good linearity in their threshold voltage shift characteristics with radiation dose. The results demonstrate the potential use of commercial p-MOSFETS as inexpensive radiation sensors for the first time.

• Journal of the Korean Geophysical Society
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• v.2 no.2
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• pp.143-152
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• 1999

We have studied a denoising technique involving wavelet transform for improving the quality of geophysical data during the preprocessing stage. To assess the effectiveness of this technique, we have made synthetic data contaminated by random noises and compared the results of denoising with those obtained by conventional low-pass filtering. The low-pass filtering of the sinusoidal signal having a sharp discontinuity between the first and last sample values shows apparent errors related to Gibbs' phenomena. For the case of bump signal, the low-pass filtering induces maximum errors on peak values by removing some high-frequency components of signal itself. The wavelet transform technique, however, denoises these signals with much less adverse effects owing to its pertinent properties on locality of wavelet and easy discrimination of noise and signal in the wavelet domain. The field data of gravity tide are denoised by using soft threshold, which shrinked all the wavelet coefficients toward the origin, and the G-factor is determined by comparing the denoised data and theoretical data.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.5
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• pp.237-243
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• 2008

Intraplantar injection of melittin has been known to induce sustained decrease of mechanical threshold and increase of spontaneous flinchings. The present study was undertaken to investigate how the melittin-induced nociceptive responses were modulated by changes of metabotropic glutamate receptor (mGluR) activity. Changes in paw withdrawal threshold (PWT), number of flinchings and paw thickness were measured at a given time point after injection of melittin ($10{\mu}g$/paw) into the mid-plantar area of rat hindpaw. To observe the effects of mGluRs on the melittin-induced nociceptions, group I mGluR (AIDA, $100{\mu}g$ and $200{\mu}g$), $mGluR_1$ (LY367385, $50{\mu}g$ and $100{\mu}g$) and $mGluR_5$ (MPEP, $200{\mu}g$ and $300{\mu}g$) antagonists, group II (APDC, $100{\mu}g$ and $200{\mu}g$) and III (L-SOP, $100{\mu}g$ and $200{\mu}g$) agonists were intrathecally administered 20 min before melittin injection. Intraplantar injection of melittin induced a sustained decrease of mechanical threshold, spontaneous flinchings and edema. The effects of melittin to reduce mechanical threshold and to induce spontaneous flinchings were significantly suppressed following intrathecal pre-administration of group I mGluR, $mGluR_1$ and $mGluR_5$ antagonists, group II and III mGluR agonists. Group I mGluR antagonists and group II and III mGluR agonists had no significant effect on melittin-induced edema. These experimental findings indicate that multiple spinal mGluRs are involved in the modulation of melittin-induced nociceptive responses.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.5
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• pp.1289-1299
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• 2007

As higher on the industrialization of chemical factories in Korea, it shows a tendency that safety accident happens more times and is bigger on its size. For preventing from and decreasing such accident, PSM(Process Safety Management) system has used in chemical factories. Though it is recognized that PSM is sutable and effective for only a intensive system technically, it could be difficult to apply to all of factories, actually. This study was proceeded for investigating the effect and problems on the application and performanance of PSM into the threshold quantity site and suggesting how fur improvement. The results are as followed; PSM system was not used effectively in the threshold quantity site of medium and small-sized enterprises because of the shortage of experts and the decrease of interest as a deregulation. As the effective performanace of PSM for preventing from industrial accident in threshold quantity site and for sattling as self-system easily, it was concluded to get an active support from the concerned government. First of all, new progrems to improve PSM should be developed continually and the progrems should be educated extensively.