• Korean journal of applied entomology
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• v.40 no.3
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• pp.197-202
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• 2001

The density of citrus red mite(CRM), Panonychus citri(McGregor), on the commercial satsuma mandarin Citrus unshiu L. groves were determined by counts of the number of CRM per leaf using by leaf sample in Jeju for 2 years. Binomial sampling plans were developed based on the relationship between the mean density per leaf(m) and the proportion of leaf infested with less than T mites per leaf($P_{T}$), according to the empirical model $ln(m)={\alpha}+{\beta}ln(-ln(1-P_{T}))$. T was defined as tally threshold, and set to 1, 3, 5 and 7 mites per leaf in this study. Increasing sample size, regardless of tally threshold, had little effects on the precision of the binomial sampling plan. Increasing sampling size had little effect on the precision of the estimated mean regardless of tally thresholds. T=1 was chosen as the best tally threshold for estimating densities of CRM based on the precision of the model. The binomial model with T=1 provided reliable predictions of mean densities of CRM observed on the commercial satsuma mandarin groves. Binomial sequential sampling procedure were developed for classifying the density of CRM. A binomial sampling program for decision-making CRM population level based on action threshold of 2 mites per leaf was obtained.

• Korean Journal of Optics and Photonics
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• v.15 no.2
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• pp.149-157
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• 2004

We have calculated the power extraction efficiency and the lasing wavelength distribution of complex-coupled(CC) DFB lasers above threshold for various｜$\chi$L｜ and facet reflectivity combinations, and we have compared the results with those at threshold. Also, we have investigated the effect of coupling coefficient ratio(CR) and the reflectivity of AR facet on the power extraction efficiency and the lasing wavelength distribution. At threshold, the single mode yield as a function of power extraction efficiency of in-phase(IP) CC DFB lasers is the same as that of anti-phase(AP) CC DFB lasers. Above threshold, however, the single mode yield as a function of power extraction efficiency of IP CC DFB lasers is much larger than that of AP CC DFB lasers. For IP CC DFB lasers, AR-HR combination has high single mode yield and large power extraction efficiency compared to other facet combinations. IP CC DFB laser with AR-HR combination for ｜$\chi$L｜of 0.8 has the highest single mode yield and largest power extraction efficiency above threshold among the cases considered. For AR-HR combination, as CR increases and the reflectivity of AR facet decreases, both single mode yield and power extraction efficiency increase due to the reduction of the spatial hole burning effect. For AR-HR combination, the lasing wavelength of CC DFB laser has distributed over the stopband of DFB. As CR increases, the lasing wavelength concentrates on the long wavelength side for IP CC DFB laser, while on the short wavelength side for AP CC DFB laser. As ｜$\chi$L｜ increases, the width of the wavelength distribution decreases and the lasing wavelength moves to the long wavelength side.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.1 no.2
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• pp.11-19
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• 2003

The purpose of this study investigated the anesthetic effects of lidocaine gel by phonophoretic transdermal delivery. The anesthetic effects were evaluated by two aspects as quantitative sensory testing and sensory nerve conduction study. Twelve healthy males(aged $23.25{\pm}2.09$ years) were studied. Exclusion criteria were ; pain, history of sensory disturbances and skin conditions in the areas to be examined. The subjects were divided into two groups; group I(lidocaine gel without ultrasound) and group II(lidocaine gel with ultrasound). The following results were obtained; 1. In changes of tactile threshold and electrical pain threshold, all groups were significantly increased(p<0.05). 2. In changes of electrical pain threshold, it was significantly differenced between the groups(p<0.05). We conclude that the transdermal delivery of lidocaine gel by phonophoresis has a possibility to use for surface anesthesia and the pain control of the superficial tissue.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.4 no.1
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• pp.85-93
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• 2006

The purpose of this study was to determine the effect of transcutaneous electrical nerve stimulation(TENS) and He-Ne laser at auricular point on delayed onset muscle soreness(DOMS). Twenty healthy adult males and females performed eccentric exercise of the elbow flexor. DOMS was induced in a standardised fashion in the nondominant elbow flexor of all subject by repeated eccentric exercise. Subject were assigned randomly to one of trees groups. Group 1 received TENS to the appropriate auricular point for biceps pain, Group 2 received laser to the appropriate auricular point for wrist pain, Group 3 received no treatment and served as controls. After exercise, treatments were applied at 24 hours and at 48 hours and at 72 hours after. Group 1 showed stastically significant increase(p<0.05) in pain threshold after treatment whereas the Group 2 and 3 did not. Group 1 showed a significant increase in pain threshold than Group 2. These results suggest that TENS has the capability to higher pain threshold but laser does not.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.2 s.332
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• pp.9-14
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• 2005

This paper reports the hot carrier induced RF performance degradation of bulk dynamic threshold voltage MOSFET (B-DTMOS) compared with bulk MOSFET (B-MOS). In the normal and moderate mode operations, the degradations of cut-off frequency $(f_{T})$ and minimum noise figure $(F_{min})$ of B-DTMOS are less significant than those of B-MOS devices. Our experimental results show that the RF performance degradation is more significant than the U performance degradation after hot carrier stressing. Also, the degradation characteristics of RF power Performance of B-DTMOS due to hot carrier effects are measured for the first time.

• Atmosphere
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• v.19 no.4
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• pp.309-318
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• 2009

Vulnerability to heat was examined for populations of 6 major cities in South Korea (Seoul, Incheon, Daejeon, Gwangju, Daegu, and Busan). Daily excess mortality and maximum temperature from 1991 to 2005 were employed in this study. The results show that the standardized mortality increase associated with a $1^{\circ}C$ increase in daily maximum temperature above the city-specific threshold explains the heat acclimatization effect better than the threshold temperature itself. The estimated increase in mortality (standardized per 10 million population) associated with a $1^{\circ}C$ increase in temperature above the threshold is 4.8 in Incheon, 4.7 in Seoul, 4.3 in Daejeon, 2.8 in Gwangju, 2.4 in Daegu, and 1.5 in Busan, well reflecting the latitudinal locations and local climates of each city. Climate models project more frequent, more intense, and longer lasting heat waves in most land areas in both hemispheres in the 21st century under increasing greenhouse gas concentrations. In order to mitigate the adverse human health impacts due to excess heat, more detailed characteristics of acclimatization to heat need to be understood and quantified.

• Korean Journal of Remote Sensing
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• v.31 no.4
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• pp.337-346
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• 2015

Water body extraction based on backscatter information is an essential process to analyze floodaffected areas from Synthetic Aperture Radar (SAR) image. Water body in SAR image tends to have low backscatter values due to homogeneous surface of water, while non-water body has higher backscatter values than water body. Non-water body, however, may also have low backscatter values in high resolution SAR image such as Kompsat-5 image, depending on surface characteristic of the ground. The objective of this paper is to present a method to increase backscatter contrast between water body and non-water body and also to remove efficiently misclassified pixels beyond true water body area. We create an entropy image using a Gray Level Co-occurrence Matrix (GLCM) and classify the entropy image into water body and non-water body pixels by thresholding of the entropy image. In order to reduce the effect of threshold value, we also propose Water Body Texture Index (WBTI), which measures simultaneously the occurrence of repeated water body pixel pair and the uniformity of water body in the binary entropy image. The proposed method produced high overall accuracy of 99.00% and Kappa coefficient of 90.38% in water body extraction using Kompsat-5 image. The accuracy analysis indicates that the proposed WBTI method is less affected by the choice of threshold value and successfully maintains high overall accuracy and Kappa coefficient in wide threshold range.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.96-96
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• 1995

It was recognized that lead intoxication reduces thiamine content in the brain of rat and this change produces the alterations of thiamine-related biochemical reactions. In the present study, it was tested whether the changes of myelin composition as well as seizure threshold induced by lead intoxication in rats may be related to these changes of thiamine status and thiamine related biochemical factors. Wistar rats were divided into five groups: Control group, Lead-treated group, Lead plus Thiamine-treated group, Thiamine-deficient group, Pyrithiamine-treated group. Each group was divided into three subgroups: 3, 7 and 16 week old group. Myelin protein and phospholipid, one of the compositions of myelin lipid, were measured in the myelin isolated from rat brain. Threshold of electric shock seizure was tested in each group. The amount of each myelin composition in lead-treated group and thiamine-deficient group was significantly lower than those of all the brains in control group, but recovery by supplementation with thiamine during lead intoxication was occurred only in the cerebellum of 3 week old animal. Thresholds of the electric shock seizure of lead treated group and thiamine deficient group in 3 and 7 week old rats were significantly lower than those of control group, while those of lead plus thiamine treated group were similar to those of control group.

• Physical Therapy Korea
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• v.9 no.2
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• pp.97-105
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• 2002

The purpose of this study was to investigate the effectiveness of the low-intensity ultrasound (noblelife) treatment on the pain points of upper trapezius muscle. The study recruited 20 patients who had trigger points in one side of the upper trapezius. The effectiveness of the low-intensity ultrasound treatment was assessed with subjective pain intensity using visual analog scale (VAS) and pressure pain threshold (PPT). The PPT was measured by pressure threshold algometer. Before and after the treatment, changes of pain were evaluated. Wilcoxon test for VAS data and paired t-test for PPT data were used for statistical significance. Compared to the pain intensity before the treatment, the pain intensity after treatment was significantly decreased (p<.05). Low-intensity ultrasound could be safely used in clinical application and at home for the treatment of patients with pain in upper trapezius muscle.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.31 no.6 s.261
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• pp.686-693
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• 2007

To perceive body movement, the nervous system uses multi-sensory cues such as vision, vestibular signals, and somatosensation. Among the multi-sensory modality, the previous researchers reported that the lower limb somatosensation plays an important role on maintaining postural balance. In this study, we examined the contribution of somatosensory cues to linear motion perception by measuring the detection threshold of the direction of linear motion with and without lower limb somatosensory constraints. Six healthy male volunteers participated in randomly ordered 33 single sinusoidal acceleration trials with the stimulus at 0.25Hz with peak magnitude ranged from 0 to 8mG. After each stimulus, subjects reported their perceived direction of motion by button press. Results showed that the reduced lower limb somatosensation significantly increased perception threshold. Without constraints, mean threshold was $0.82{\pm}0.23mG$, while it was $1.23{\pm}0.35mG$ with reduced lower limb somatosensation. The results suggest that without visual cues, perception of the movement direction strongly depends on the lower limb somatosensory information.