• ETRI Journal
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• 제37권5호
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• pp.979-989
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• 2015

Recently, Hou and others introduced a (2, n) block-based progressive visual cryptographic scheme (BPVCS) in which image blocks can be gradually recovered step by step. In Hou and others' (2, n)-BPVCS, a secret image is subdivided into n non-overlapping image blocks. When t ($2{\leq}t{\leq} n$) participants stack their shadow images, all the image blocks associated with these t participants will be recovered. However, Hou and others' scheme is only a simple 2-out-of-n case. In this paper, we discuss a general (k, n)-BPVCS for any k and n. Our main contribution is to give two constructions (Construction 1 and Construction 2) of this general (k, n)-BPVCS. Also, we theoretically prove that both constructions satisfy a threshold property and progressive recovery of the proposed (k, n)-BPVCS. For k = 2, Construction 1 is reduced to Hou and others' (2, n)-BPVCS.

• 대한약침학회지
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• 제8권2호
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• pp.83-90
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• 2005

Objective : This study was performed to compare needle acupuncture combined herbal acupuncture therapy with only needle acupuncture therapy in VAS and pain threshold. Methods : We used pressure algometer to evaluate the change of pain threshold before and after treatment. The numberical value of pressure algometer is obtained twice and averaged by identical acupuncturist. Visual analogue scale(VAS) was used to estimate the efficacy of needle acupuncture combined herbal acupuncture therapy. Result : The following results were obtained; 1. The significant difference in VAS was showed before and after treatment in only needle acupuncture therapy. 2. The significant difference in pain threshold and VAS was showed before and after treatment in needle acupuncture combined herbal acupuncture therapy. 3. In the pain threshold, the significant difference between only needle acupuncture and needle acupuncture combined herbal acupuncture therapy was not showed. 4. Needle acupuncture combined herbal acupuncture therapy showed the more effective change of VAS than only needle acupuncture therapy. Conclusions : In the pain control, needle acupuncture combined herbal acupuncture therapy is more effective than only needle acupuncture therapy.

• Journal of Acupuncture Research
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• 제29권4호
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• pp.25-34
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• 2012

Objectives : This study was conducted to investigate the effects of fixed-intensity and varied-intensity electroacupuncture in pain and sensory threshold concerning parameters visual analogue scale(VAS), brief pain inventory(BPI) and quantitative sensory testing(QST), among chronic tension headache patients. Methods : Thirty patients with chronic tension headache were randomly assigned to three groups and received different kinds of electroacupuncture at $ST_{36}$ and $ST_{37}$. Group A received fixed-intensity electroacupuncture(fixed-EA), group B received varied-intensity electroacupuncture (varied-EA), and group C received only acupuncture treatment without electrical stimulation as a control group. The intervention was given three times per week, and continued in two weeks. All the experiments were conducted blindly. Results : Fixed-EA group showed a significant decrease of VAS and BPI compared to the baseline measurement, while both varied-EA and control group did not. Of the parameters of QST, subtraction of heat pain threshold(HPT) and cold pain threshold(CPT) slightly increased in all groups, but this was not significant. Conclusions : These results suggest that fixed-EA reduce pain and improve quality of life in patients with chronic tension headache and that acupuncture may regulate patient's pain sensitivity through changing sensory threshold.

• 한방재활의학과학회지
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• 제21권4호
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• pp.191-203
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• 2011

Objectives: The purpose of this study is to investigate the clinical effects of heating-conduction therapy on lateral ligament injury induced by ankle sprain grade II. Methods: The 67 outpatients who were diagnosed as ankle sprain grade II were performed heating-conduction acupuncture therapy on lateral ligament injury. To evaluate the efficiency of heating-conduction acupuncture therapy, pain threshold with pressure algometer and visual analogue scale(VAS) were applied pretreatment and after 1st, 2nd treatment. Results: 1. The pain threshold and VAS score after 1st and 2nd treatment with an isolated injury of the anterior talofibular ligament showed statistically significant improvement compared with pretreatment. 2. The VAS score after 1st and 2nd treatment with an combined injury to the anterior talofibular and the calcaneofibular ligament showed statistically significant improvement compared with pretreatment. 3. The VAS score after 1st and 2nd treatment with an combined injury to the anterior talofibular, calcaneofibular and posterior talofibular ligament showed statistically significant improvement compared with pretreatment. 4. After 1st and 2nd treatment on the posterior talofibular ligament and after 2nd treatment on the anterior taofibular and calcaneofibular ligament with an combined injury to the anterior talofibular, calcaneofibular and posterior talofibular ligament the pain threshold showed statistically significant improvement compared with pretreatment. 5. Between isolated injury and combined injury of lateral ligament, the difference in pain threshold and VAS score was not statistically significant. Conclusions: Heating-conduction acupuncture therapy has clinical effects of pain reduction on patient with an isolated injury and combined injury of lateral ligament induced by ankle sprain grade II.

• 한방재활의학과학회지
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• 제20권3호
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• pp.119-129
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• 2010

Objectives : The purpose of this study is to investigate the clinical effects of heating-conduction acupuncture therapy on ligament injury induced by acute ankle sprain. Methods : From september 16, 2008 to April 17, 2010, the 28 outpatients who had admitted to department of oriental rehabilitation medicine, Dae-Jeon oriental Medical hospital, Dae-Jeon university with acute ankle sprain were performed heating-conduction acupuncture therapy on anterior talofibular and calcaneofibular ligament injury. To evaluate the efficiency of heating-conduction acupuncture therapy, pain threshold with pressure algometer and visual analogue scale(VAS) were applied before treatment and after 1st, 2nd treatment. Results : 1. The pain threshold and the VAS score showed statistical significant improvement after 1st treatment on calcaneofibular and anterior talofibular ligament injury. 2. The VAS score after 2nd treatment on calcaneofibular and anterior talofibular ligament injury showed statistical significant improvement compared with that after 1st treatment. 3. The pain threshold after 2nd treatment on calcaneofibular and anterior talofibular ligament injury did not show statistical significant improvement compared with that after 1st treatment. 4. The difference between anterior talofibular and calcaneofibular ligament injury was not statistical significant in pain threshold and VAS score. Conclusions : Heating-conduction acupuncture therapy has clinical effects of pain reduction on patient with calcaneofibular ligament injury as well as anterior talofibular ligament induced by acute ankle sprain.

• 대한기계학회논문집A
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• 제31권6호
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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.

• Restorative Dentistry and Endodontics
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• 제41권3호
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• pp.159-166
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• 2016

The purpose of this review was to suggest practical criteria for the clinical translucency evaluation of direct esthetic restorative materials, and to review the translucency with these criteria. For the evaluation of reported translucency values, measuring instrument and method, specimen thickness, background color, and illumination should be scrutinized. Translucency parameter (TP) of 15 to 19 could be regarded as the translucency of 1 mm thick human enamel. Visual perceptibility threshold for translucency difference in contrast ratio (${\Delta}CR$) of 0.07 could be transformed into ${\Delta}TP$ value of 2. Translucency differences between direct and indirect resin composites were perceivable (${\Delta}TP>2$). Universal and corresponding flowable resin composites did not show perceivable translucency differences in most products. Translucency differed significantly by the product within each shade group, and by the shade group within each product. Translucency of human enamel and perceptibility threshold for translucency difference may be used as criteria for the clinical evaluation of translucency of esthetic restorative materials.

• 말소리와 음성과학
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• 제2권3호
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• pp.151-156
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• 2010

The purpose of this study was to develop a computer-animated pure tone audiometry for screening (CAPTAS) for toddler and to determine its validity and reliability. The CAPTAS utilizes an animated cartoon story producing visual and auditory stimuli. The intensities were 40 dB, 60 dB, 80 dB. The frequencies were 500 Hz, 1000 Hz, 2000 Hz, and 4000 Hz. The subjects were 20 (9 males and 11 females) severely hearing impaired children. As a result, The correlation coefficient between mean hearing threshold of children who were able to perform PTA and average hearing threshold of CAPTAS was performed and it revealed CAPTAS's high validity. And to verify the reliability of the re-test, all children had the CAPTAS and repeated it periodically. The result confirmed the reliability.

• International Journal of Advanced Culture Technology
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• 제8권3호
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• pp.254-259
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• 2020

The medical bed developed in this study is an electrically driven segmental keyboard. First describe the instrument of the segmental bed specially designed for pressure ulcer prevention, then the motor control system and pressure ulcer prevention operation of the bed. The main factor of pressure ulcer generation is displayed as body pressure x time, and when the keyboard falls, the body pressure becomes zero, and the pressure becomes higher than the threshold even if the body pressure is above the threshold, the pressure control algorithm has been developed. Therefore, using the proposed pressure control method, it has no particular ulcer occurred theoretically.

• 반도체디스플레이기술학회지
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• 제10권1호
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• pp.113-118
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• 2011

This paper proposes computer visual inspection algorithms for PCB defects which are found in a manufacturing process. The proposed method can detect open circuit and short circuit on bare PCB without using any reference images. It performs adaptive threshold processing for the ROI (Region of Interest) of a target image, median filtering to remove noises, and then analyzes connected components of the binary image. In this paper, the connected components of circuit pattern are defined as 6 types. The proposed method classifies the connected components of the target image into 6 types, and determines an unclassified component as a defect of the circuit. The analysis of the original target image detects open circuits, while the analysis of the complement image finds short circuits. The machine vision inspection system is implemented using C language in an embedded Linux system for a high-speed real-time image processing. Experiment results show that the proposed algorithms are quite successful.