• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.12C
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• pp.1660-1668
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• 2004

This paper proposes a Voice Activity Detection (VAD) algorithm based on Radial Basis Function (RBF) network using dual threshold. The k-means clustering and Least Mean Square (LMS) algorithm are used to upade the RBF network to the underlying speech condition. The inputs for RBF are the three parameters in a Code Exited Linear Prediction (CELP) coder, which works stably under various background noise levels. Dual hangover threshold applies in BRF-VAD for reducing error, because threshold value has trade off effect in VAD decision. The experimental result show that the proposed VAD algorithm achieves better performance than G.729 Annex B at any noise level.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.61-66
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• 2005

In this paper, we analyzed the error rate Performance of Convolution coded 16 QAM signal with Optimum Threshold Detection in Rician Fading Enviroments. The performance of 16-QAM signal with CTD (conventional threshold detection) which employs convolution coding technique was analyzed and the performance improvement of convolution coded 16-QAM signal with OTD (optimum threshold detection) which is varied according to fading parameter 'K' and AWGN in Rician Fading channel was simulated. As a result of analysis, it was shown the effect of performance improvement to overcome the environment of mobile radio data communication channel.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.765-767
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• 2010

In this paper, the variations of threshold voltage characteristics for ratio of channel length and thickness have been alanyzed for DG(Double Gate)MOSFET having top gate and bottom gate. Since the DGMOSFET has two gates, it has advantages that contollability of gate for current is nearly twice and SCE(Short Channel Effects) shrinks in nano devices. The channel length and thickness in MOSFET determines device size and extensively influences on SCEs. The threshold voltage roll-off, one of the SCEs, is large with decreasing channel length. The threshold voltage roll-off has been analyzed with various ratio of channel length and thickness for DGMOSFET in this study.

• Korean Journal of Exercise Nutrition
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• v.14 no.2
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• pp.95-101
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• 2010

The purpose of this study was to evaluate changes of body composition, cardio-respiratory function in ventilation threshold (VT) and maximal state exercise, systolic (SBP) and diastolic blood pressure (DBP) and serum nitric oxide (NO) production during acute reducing salt (RS) supplementation in college elite athletes. Variables of cardio-respiratory function during rest, ventilation threshold and maximal exercise was not shown a significantly difference between RS supplementation and non-supplementation, there was shown a significant increase in ventilation threshold time (p<0.05) and exhaustion time (p<0.05) during RS supplement compared to non-supplement. SBP and DBP were not shown a significant difference between RS supplement and non-supplement. This result suggests that acute intake of RS is not increased a blood pressure. Serum NO production was not significant difference in the RS supplement group, but it was shown a significantly increased levels (p<0.01, vs. recovery 30 min.) immediately after maximal exercise in the non-supplement group. This result suggests that acute intake of RS have important role in inhibition of serum NO production during maximal exercise. Conclusively, This study suggest that acute intake of RS was not influence in body composition variables, but it was positive effect in ventilation threshold time, exhaustion time, maintenance of blood pressure and inhibition of serum NO production in maximal treadmill exercise.

• The Journal of Korean Physical Therapy
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• v.6 no.1
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• pp.5-15
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• 1994

The purpose of this study was to examine the effect of electroanalgeia and $\beta-endorphin$ action by acupuncture-like (Lof/Hil) transcutaneous electrical nerve stimulation (TENS) applied to acupuncture points. Twelve healthy adult male aged between 19 ann 25 were randomly assigned to TENS group (n=6) and naloxone group (n=6). Subjects of both groups were strongly stimulated TENS with 4 pps and $200{\mu}s$ for 30 minutes on the LI 3 and LI 10 meridian points of dominant am. Naloxone group was injected naloxone hydrochloride before TENS application. The experimental pain threshold was measured by chronaxie meter CX-2 on the distal end of radius just before and after TENS application. The levels of plasma $\beta-endorphin$ and ACTH. serum cortisol and urinary 17-OHCS were analyzed by radioimmunoassay (RIA) kits before and after TENS application. In TENS group, there was a significant increase of experimental pain threshold (p<0.01), plasma $\beta-endorphin$ level (p<0.05), serum cortisol level (p<0,001) and urinary 17-OHCS levels (p<0.05) after TENS application. The plasma ACTH level was not significantly increased, but it showed an increasing tendency. In naloxone group, although there was a decreasing trend, ACTH and cortisol level did not show a significant change, but $\beta-endorphin$ and 17-OHCS level were significantly decreased (p<0.01). The result of this study stewed that acupuncture-like TENS induced analgesic effect, such that the levels of plasma $\beta-endorphin$, plasma ACTH, serum cortisol and urinary 17-OHCS were concomitantly increased with experimental pain threshold. It is suggested that the analgesic mechanism of the acupuncture-like TENS probably related to endogenous opioid component such as $\beta-endorphin$.

• Polymer(Korea)
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• v.27 no.1
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• pp.40-45
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• 2003

In this work, the effect of different contents of $Fe_3O_4$ and temperature variation on the electrical conductivity ($\sigma$) in the polar acrylonitrile butadiene rubber (NBR)/$Fe_3O_4$ (magnetite) mixture system was investigated. It was found that the percolation threshold concept holds true for the conductive particle-filled composites where $\sigma$ indicates a nearly sharp increase when the concentration of magnetite in the mixture exceeds 22%. The temperature dependence of $\sigma$ was thermally activated below and at the percolation threshold ($P_c$). Magnetite acted as reinforcing and conductive filler for NBR. At room temperature and higher voltages, the electrical current was proportional to the square of voltage ($I{\propto}V^2$) for the composites which contain 30 phr of magnetite. Moreover, it was shown that the composites with magnetite of 50 phr showed the highest tensile strength and elongation at break, which was due to the formation of optimal physical interlock and crosslinking. The results of 100%, 200%, and 300% Young moduli said that the moduli are largely correlated with reinforcement effect of magnetite and viscosity of the blends from torque curve.

• Journal of Korea Entertainment Industry Association
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• v.13 no.7
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• pp.461-468
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• 2019

The purpose of this study was to investigate effect of upper cervical stabilization exercise on Temporomandibular Disorder(TMD) and pressure pain threshold. 36 subjects were divided into two groups: upper cervical stabilization exercise group(UCSEG) and control on three times a week for a total of four weeks. The upper cervical stabilization group showed more significant effect than the control group (p <.01, 95% CI: 8.074, 16.899). (p <.01, 95% CI: .826, 3.243). In the change of pressure pain threshold, the upper cervical stabilization group showed significant improvement in both the masticatory muscle(p <.01, 95% CI: .251, 1.382) and masticatory muscle(p <.01, 95% CI: .462, 1.826).The results of this study showed that the upper cervical stabilization exercise was effective that TMD. It will be able to provide more effective interventions for patients suffering from TMD, and to suggest new approaches for TMD patients.

• The Journal of Korean Physical Therapy
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• v.6 no.1
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• pp.171-183
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• 1994

Purphose. This present study examines the effect of brief, intense transcutaneous electrical nerve stimulation(BTENS) on sensory nerve conduction, electrical pain threshold, and two-point discrimination measured at the superficial radial nevre distribution in 20 healthy subjects. Subjects. Twenty volunteercs, (10 females and 10 males(age range : 20-38 years : $mean{\pm}SD\;:\;27.00{\pm}5.12$), only subjects without prior traumatological and pathological were eligible to participated in this study. Methods. Nerve conduction were determined for the right superficial radial nerve. Electrical pain threshold were determined for the right wrist ipsilateral to the site of BTENS. Small disc electrodes were attached to the surface of the skin stradding the end of the radius. Square wave electrical pulses were delivered from an isolated stimulator through a constant current device at a frequency of 2 Hz(5 ms pulse width). Two-point discrimination, measured on the sensory distribution of superficial radial nerve. BTENS was delivered using a Max-SD( Medical design co.) portable battery powered stimulator. A cicular Ag/AgCl electrode in contact with hypertonic saline gel was attached to the lateral(radial side) surface of the forearm. Results. No significant effects were observed between stimulation methods in the prestimulation cycle(multi-way ANOVA repeated measures : distal latency ; F1.14=0.332. amplitude ; F 0.80=0.445, pain threshold ; F0.06=0.940.2 point discrimination ; F1.50=0.236). Highly significant effects were observed time with the pretreatment and 6 posttreatment cycles(p<0.01). Mighty significants differences in nerve conduction and pain threshold were found using un multi-way ANOVA repeated measures among stimulation methods for each cycles(p<0.01). Conclusion and Discussion The authors concludes that both nerve conduction and pain threshold changes are associated with therapy (stimulation) level of BTENS.

• Journal of Korean Medicine Rehabilitation
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• v.24 no.2
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• pp.131-140
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• 2014

Objectives This study was aimed at comparing clinical effectiveness among trigger point treatment, Self-exercise treatment, trigger point - self-exercise cooperative treatment for neck pain caused by traffic accidents. Methods 63 patients with neck pain by traffic accidents were divided into 3 groups. Different types of treatments were carried out for each groups ; group A with trigger point, group B with self-exercise, group C with trigger point and self-exercise cooperative treatment. 3 groups were also treated with general acupuncture and herb-medicine treatment. Pain threshold, visual analogue scale (VAS), and neck disability index (NDI) were checked on a daily basis. SPSS ver. 18.0 for Windows was used for analysis of data. The effectiveness of treatment of each groups were verified by using paired test and one-way repeated-measures ANOVA test, and the comparison of VAS, NDI and pain threshold were demonstrated by independent samples t-test. Results 3 groups all showed significant difference in pain threshold, VAS and NDI after 8 days later. Group C showed more improvement in pain threshold, VAS and NDI than shown in group A and B. In the first period (from pre-treatment to 4th day treatment) group C showed significant difference in NDI and pain threshold but not in VAS as compared to group A and B. In the second period (from 4th treatment to 8th day treatment), Group C showed significant difference in pain threshold, VAS and NDI as compared to group A and B. Conclusions Trigger point - self-exercise cooperative treatment is proved to be more helpful to improve the unstability and reduce neck pain than trigger point treatment or self-exercise treatment only, therefore eventually leading to better satisfaction for patients with neck pain.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.7
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• pp.665-670
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• 2016

In this paper, we suggest the design of OP-AMP using MOSFET in the operation of sub-threshold condition as a basic unit of an IoT. The sub-threshold operation of MOSFET is useful for an ultra low power consumption of sensor network system in the IoT, because it cause the supply voltage to be reduced. From the simulation result using 0.35 um CMOS process, the supply voltage, VDD can be reduced with 0.6 V, open-loop gain of 43 dB and the power consumption was evaluated with about $1.3{\mu}W$ and the active size for an integration was measured with $64{\mu}m{\times}105{\mu}m$. It is expected that the proposed circuit is applied to the low power sensor network for IoT.