• Title/Summary/Keyword: Visual threshold

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Evaluation of Results of Dynamic Immersion Test Using Digital Image Analysis (Digital Image Analysis를 이용한 동적수침시험 평가방법의 개선 연구)

  • Son, Jeong Tan;Lee, Jin Wook;Rhee, Suk Keun;Hwang, Sung Do;Im, Jeong Hyuk
    • International Journal of Highway Engineering
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    • v.18 no.4
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    • pp.47-53
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    • 2016
  • PURPOSES : The objective of this study was to evaluate the results of the dynamic immersion test (DIT) through digital image analysis (DIA). METHODS : The asphalt binder retained post DIT was inspected visually by more than three investigators. However, because visual observations can be subjective, depending on the inspector's skills and knowledge, DIA was also performed. The threshold value for the DIA was determined by a mesh analysis, in which the digital image to be analyzed is divided into very small meshes. In addition, the bitumen bond strength (BBS) test was also performed to the compare the visual results with the mechanical values. RESULTS AND CONCLUSIONS : Depending on the materials used, various methods can be used to predict the behavior of retained asphalt. However, the increasing ratio in the trend of retained asphalt shows different behaviors among the evaluation methods. In this study, the results of the visual observations were significantly different from those of the DIA, the mesh analysis, and the BBS tests. Thus, DIA is an appropriate method for evaluating the results of the DIT. However, in order to use this technique in the field, it is necessary to determine a more reasonable threshold value by performing DIA on various materials.

The effects of active release technique on the gluteus medius for pain relief in persons with chronic low back pain

  • Tak, Sajin;Lee, Yongwoo;Choi, Wonjae;Lee, Gyuchang
    • Physical Therapy Rehabilitation Science
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    • v.2 no.1
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    • pp.27-30
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    • 2013
  • Objective: Low back pain is a primary of source of dysfunction and economic costs. Gluteus medius muscle co-activation and activity pattern change caused the low back pain. Active release technique (ART) is a patented, non-invasive, soft tissue treatment process that both locates and breaks down the scar tissue and adhesions. The purpose of this study was to assess the effects on chronic low back pain using ART on gluteus medius so that suggest usable treatment method for treating chronic low back pain. Design: One group pretest-posttest design. Methods: Twelve patients with chronic low back pain were participated in this study. Subjects in ART group were received 2 times a week for 3 weeks treatments with either ART on gluteus medius muscle trigger points. Outcome measures were conducted by pain intensity with a pain visual analogue scale and pressure pain threshold on gluteus medius. Results: Completion of the intervention, the visual analogue scale was decreased in ART group (p<0.05). Also pressure pain threshold was decreased in ART group (p<0.05). Conclusions: Our results suggest that the response to ART may be usable to treat low back pain. ART was presented to reduce pain level of low back in people with chronic low back pain. Further study is required to management for low back pain due to gluteus medius and more ART study.

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A Wavelet-Based Watermarking Scheme of Digital Image Using ROI Method (ROI를 이용한 웨이브렛 기반 디지털 영상의 워터마킹 기법)

  • Kim, Tae-Jung;Hong, Choong-Seon;Sung, Ji-Hyun;Hwang, Jae-Ho;Lee, Dae-Young
    • The KIPS Transactions:PartB
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    • v.11B no.3
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    • pp.289-296
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    • 2004
  • General watermarking techniques tend not to consider intrinsic characteristics of image, so that watermarks are embeded to entire images. In this paper, we present a watermarking algorithm based on wavelet domain, and the watermark is embedded into large coefficients in region of interest(ROI) being based on principle of multi-threshold watermark coding(MTWC) for robust watermark insertion. We try to accomplish both image duality and robustness using human visual system(HVS). The watermarks are embedded in middle frequency bands because the distortion degree of watermarked images appears to be less than lower frequency bands, and the embedded watermarks in the middle bands showed high extraction ratios after some distortion. The watermarks are consisted of pseudo random sequences and detected using Cox's similarity mesurement.

Synergism Between Zinc and Taurine in the Visual Sensitivity of the Bullfrog's Eye

  • Kim, Hyun-Jung;Kim, You-Young
    • Journal of Photoscience
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    • v.7 no.3
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    • pp.115-121
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    • 2000
  • Although there are high concentrations of zinc and taurine in ocular tissue, their exact role and correlation in the visual process are not clear. The purpose of present study was to clarity this point using electroretinogram (ERG) recording and spectrophotometer measurements before and after zinc and taurine treatment in bullfrog's eye. The optimal zinc concentration used in this study was 10$^{-2}$ M ZnCl$_2$120 ${mu}ell$/12$m\ell$ ringer solution while the optimal turine concentration was 10$^{-2}$ M taurine 12${mu}ell$/12$m\ell$ ringer solution. For the effects of zinc and taurine on the retinal function, the changes of ERG parameters (especially threshold and b-wave) and absorption spectra were observed before and after treatment. It is noteworthy that high concentrations of zinc and taurine present in the retinal pigment epithelium and the retina. Our results indicate that dark-adapted ERG threshold became elevated and the peak amplitude of b-wave was increased with zinc and taurine treatment. Furthermore there are some synergism effects between zinc and taurine as a result of co-treatment. In spectral scan, absorbance increment due to zinc and taurine treatment was shown over the whole range of spectral range (300-750 nm) with some differences in absorbance increment depending on the case of treatment. As the results of above we believe that zinc and taurine, which are abundant in the retinal pigment epithelium and the retina particularly, may be essential factors for visual process, have some synergism with each other and be required to improve the visual sensitivity during visual adaptation.

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New Appraisal Method for Blocking Effects in Subimage Coding

  • Park, Jae-Ho;Kwak, Hoon-Sung
    • Journal of Electrical Engineering and information Science
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    • v.1 no.1
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    • pp.77-81
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    • 1996
  • Considering the human visual masking property, a modified relationship between the activity function and the visibility threshold is developed. This leads to a novel objective appraisal method for blocking effects in a lossy subimage coding by virtue of the human visual sensitivity. The appraisal criterion is examined using a series of reconstructed images that are DCT-coded at various bit rates. Experimental results show that the presented blocking effect measure well agrees with the subjective ranking.

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Seismic risk investigation for reinforced concrete buildings in Antalya, Turkey

  • Kepenek, Engin;Korkmaz, Kasim A.;Gencel, Ziya
    • Computers and Concrete
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    • v.26 no.3
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    • pp.203-211
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    • 2020
  • Turkey is located in one of the most seismically active regions of in Europe. The majority of the population living in big cities are at high seismic risk due to insufficient structural resistance of the existing buildings. Such a seismic risk brings the need for a comprehensive seismic evaluation based on the risk analysis in Turkey. Determining the seismic resistance level of existing building stock against the earthquakes is the first step to reduce the damages in a possible earthquake. Recently in January 2020, the Elazig earthquake brought the importance of the issue again in the public. However, the excessive amount of building stock, labor, and resource problems made the implementation phase almost impossible and revealed the necessity to carry out alternative studies on this issue. This study aims for a detailed investigation of residential buildings in Antalya, Turkey. The approach proposed here can be considered an improved state of building survey methods previously identified in Turkey's Design Code. Antalya, Turkey's fifth most populous city, with a population over 2.5 Million, was investigated as divided into sub-regions to understand the vulnerability, and a threshold value found for the study area. In this study, 26,610 reinforced concrete buildings between 1 to 7 stories in Antalya were examined by using the rapid visual assessment method. A specific threshold value for the city of Antalya was determined with the second level examination and statistical methods carried out in the determined sub-region. With the micro zonation process, regions below the threshold value are defined as the priority areas that need to be examined in detail. The developed methodology can be easily calibrated for application in other cities and can be used to determine new threshold values for those cities.

Effects of Acupuncture on Upper Back Myofascial Pain and Pain Pressure Threshold (경견부 근막통증증후군에 대한 침치료 효과와 압통역치의 변화)

  • Cho, Seong-Gyu;Seo, Jung-Chul;Choi, Do-Young;Kim, Yong-Suk
    • Journal of Acupuncture Research
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    • v.18 no.5
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    • pp.1-10
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    • 2001
  • Objective : This study was performed to confirm the effects of acupuncture on myofascial pain syndrome(MPS) through the change of visual analogue scale(VAS) and pain pressure threshold(PPT) and the usefulness of pressure algometer on the evaluation of pain. Methods : We perfomed this study with 20 outpatients complaining of upper back pain. Before acupuncture therapy(AT), immediately after AT and 2-3 days after AT, we respectively checked visual analogue scale(VAS) and pain pressure threshold(PPT) through pressure algometer, with patients seated and relaxed. The PPT was checked at major trigger point of upper trapezius, levator scapulae, supraspinatus, infraspinatus, rhomboideus minor. and the patients were needled at the same points and maintained for 15 minutes. Results : VAS of immediately after AT was mild higher than that of before AT, but not significantly different. and VAS of 2-3 days after AT was significantly lower than before AT and immediately after AT. PPT of immediately after AT was lower than before PT, but not significantly different. PPT of 2-3 days after AT was significantly higher than that of before AT and immediately after AT. Also PPT was significantly correlated with VAS. Conclusion : PPT of omen was signicantly lower than that of men. and there was no significant difference by age. PPT was increased according to pain duration. Effectiveness of acupuncture on myofascial pain syndrome through PPT and VAS is showed at 2-3 days after AT rather than immediatly after AT. and pressure algometer is useful for the evaluation of Acupuncture therapy on myofascial pain syndrome.

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Dose dependent effects of Jungsongouhyul Pharmacopuncture on Low Back Pain (요통환자에서 중성어혈 약침 사용 용량에 따른 효과)

  • Jeong, Man-Jin;Kwon, O-Gon;Woo, Chang-Hoon;An, Hee-Duk
    • Journal of Pharmacopuncture
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    • v.14 no.2
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    • pp.45-52
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    • 2011
  • Objectives : The object of this study is to analyse about Low Back Pain's intensity according to dosage of Jungsongouhyul pharmacopuncture. Method : Three groups were made with 15 patients in Po-Hang Oriental Hospital, which is affiliates to Daegu Haany University. They were observed August 1st, 2010 to September 30th. 2010. Each group was treated by based on acupuncture, herb and other therapy and differential dosage of Jungsongouhyul pharmacopuncture 0,4, 0.8, and 1.2cc. We had measured pain threshold and Visual Analog Scale during first week of their admission. The statistical analysis was performed by using the oneway ANOVA and Tukey's test. Result : Change of VAS was not statistically significant. Change of pain threshold was statistically significant. Multiple comparisons of pain threshold between the group1,2 was not statistically significant. Multiple comparisons of pain threshold between the group1,3 and group2,3 was statistically significant. Conclusions : Jungsongouhyul Pharmacopuncture 1.2cc was more effective than 0.4 and 0.8cc.

The Clinical Effects of Heating-Conduction Acupuncture Therapy(tentatively called) for Anterior Talofibular Ligament Injury Induced by Acute Ankle Sprain (전열침(가칭)이 급성 족관절 염좌로 인한 전거비 인대 손상에 미치는 임상적 효과)

  • An, Soon-Sun;Jang, Hyo-Kil;Heo, Dong-Seok
    • Journal of Korean Medicine Rehabilitation
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    • v.19 no.4
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    • pp.127-134
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    • 2009
  • Objectives : The purpose of this study is to investigate the clinical effects of heating-conduction acupuncture therapy on anterior talofibular ligament injury induced by acute ankle sprain. Methods : From October 31, 2008 to July 21, 2009, the 11 outpatients who had admitted to department of oriental rehabilitation medicine, Dae-Jeon oriental medicine hospital, Dae-Jeon university with acute ankle sprain were performed heating-conduction acupuncture therapy on anterior talofibular 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 score and the VAS score showed statistical significant improvement after 1st treatment. 2. The pain threshold score and the VAS score showed improvement but had no statistical significance after 2nd treatment. 3. The difference between left and right were not statistical significant in pain threshold score and VAS score. Conclusions : Heating-conduction acupuncture therapy has clinical effects of pain reduction on patient with anterior talofibular ligament injury induced by acute ankle sprain.

Multimodal Curvature Discrimination of 3D Objects

  • Kim, Kwang-Taek;Lee, Hyuk-Soo
    • Journal of the Institute of Convergence Signal Processing
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    • v.14 no.4
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    • pp.212-216
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    • 2013
  • As virtual reality technologies are advanced rapidly, how to render 3D objects across modalities is becoming an important issue. This study is therefore aimed to investigate human discriminability on the curvature of 3D polygonal surfaces with focusing on the vision and touch senses because they are most dominant when explore 3D shapes. For the study, we designed a psychophysical experiment using signal detection theory to determine curvature discrimination for three conditions: haptic only, visual only, and both haptic and visual. The results show that there is no statistically significant difference among the conditions although the threshold in the haptic condition is the lowest. The results also indicate that rendering using both visual and haptic channels could degrade the performance of discrimination on a 3D global shape. These results must be considered when a multimodal rendering system is designed in near future.