• Title/Summary/Keyword: temporal difference

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A Method of Frame Synchronization for Stereoscopic 3D Video (스테레오스코픽 3D 동영상을 위한 동기화 방법)

  • Park, Youngsoo;Kim, Dohoon;Hur, Namho
    • Journal of Broadcast Engineering
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    • v.18 no.6
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    • pp.850-858
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    • 2013
  • In this paper, we propose a method of frame synchronization for stereoscopic 3D video to solve the viewing problem caused by synchronization errors between a left video and a right video using the temporal frame difference image depending on the movement of objects. Firstly, we compute two temporal frame difference images from the left video and the right video which are corrected the vertical parallax between two videos using rectification, and calculate two horizontal projection profiles of two temporal frame difference images. Then, we find a pair of synchronized frames of the two videos by measuring the mean of absolute difference (MAD) of two horizontal projection profiles. Experimental results show that the proposed method can be used for stereoscopic 3D video, and is robust against Gaussian noise and video compression by H.264/AVC.

Asymmetry of Medial and Lateral Temporal Regional Glucose Metabolism in Temporal Lobe Epilepsy by F-18-FDG PET (측두엽 간질에서 F-18-FDG PET에 나타난 측두엽 내외측 부위별 대사의 차이)

  • Lee, Dong-Soo;Yeo, Jeong-Seok;Song, Ho-Cheon;Lee, Sang-Kun;Kim, Hyun-Jip;Chung, June-Key;Lee, Myung-Chul
    • The Korean Journal of Nuclear Medicine
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    • v.33 no.1
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    • pp.28-39
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    • 1999
  • Purpose: We investigated the difference of glucose metabolism of medial and lateral temporal lobes of patients with temporal lobe epilepsy (TLE) utilizing quantitative comparison of regional metabolic activities using asymmetric index. Materials and Methods: We studied 19 pathologically proven mesial TLE and 25 lateral TLE patients. Lateral TLE patients were either normal on magnetic resonance imaging (cryptogenic: n=14) or had structural lesions (lesional: n= 11). Asymmetric index (ASI) was calculated as [(ipsilateral-contralateral)/(ipsilateral+contralateral)]${\times}200$. Results: ASI of medial and lateral lobes of mesial TLE was decreased ($-16.4{\pm}8.3$ and $-12.1{\pm}5.5$, respectively). In cryptogenic lateral TLE, ASI of lateral temporal lobe was decreased ($-11.8{\pm}4.7$), whereas that of medial temporal lobe was not decreased ($-4.6{\pm}6.3$). ASI of medial lobe of lesional lateral TLE was $-7.3{\pm}9.1$, which was significantly different from that of mesial TLE (p<0.05). Patients with lesional lateral TLE had evident metabolic defects or decrease (ASI: $-22{\pm}10.5$) in lateral temporal lobe. While we could not find the difference of metabolic activity in lateral temporal lobes between cryptogenic lateral TLE and mesial TLE patients, the difference of metabolic activity was significant in medial temporal lobes which was revealed by ASI quantitation. Conclusion: Asymmetric decrease of metabolic activity in both medial and lateral temporal lobes indicates medial temporal epilepsy. Symmetry of metabolic activity in medial temporal lobe combined with asymmetry of that in lateral temporal lobe may give hints that the epileptogenic zone is lateral.

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Experimental Study on Reduction of Temporal Dark Image Sticking on Bright Screen in AC-PDPs Using RF-Plasma Treatment on MgO layer

  • Park, Choon-Sang;Kim, Jae-Hyun;Tae, Heung-Sik
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.101-103
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    • 2009
  • Minimizing the residual impurity level on the MgO layer is the key factor for reducing temporal dark image sticking on bright screen. In this paper, to reduce the residual impurity level on the MgO layer of 50-in. full-HD ac-PDP with He (35%) - Xe (11%) contents, RF-plasma treatments on the MgO layer are adopted under various gases for plasma treatment. As a result of monitoring the difference in the display luminance between the before and after 5-min. sustain discharge with a square-type image at peak luminance, the Ar and Ar>$O_2$ plasma treatments can reduce the temporal dark image sticking on the bright screen in an ac-PDP.

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Influence of Temporal Dark Image Sticking Characteristics on Bright Screen with Various He contents in 50-in. AC-PDPs

  • Kim, Sun-Ho;Park, Choon-Sang;Kim, Jae-Hyun;Tae, Heung-Sik
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.716-718
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    • 2009
  • The effects of the temporal dark image sticking phenomena on bright screen were investigated with various He, Ne contents and a high Xe content fixed at 11% in the 50-in. ac-PDPs. In this work, the disappearance time and the display luminance between the before and after discharge in the discharge and non-discharge regions were measured with 0%, 35%, and 50% He contents. Consequently, the temporal dark image sticking on bright screen was reduced with the increase of He contents compared with the non-He (0%) content.

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A COMPARATIVE ELECTROMYOGRAPHIC STUDY OF THE MASSETER AND ANTERIOR TEMPORAL MUSCLES DURING MASTICATORY FUNCTION OF SUBJECTS WITH NATURAL TEETH AND COMPLETE DENTURE WEARERS (유치악자와 총의치 장착자의 저작운동시 교근과 측두근의 근할성도에 관한 비교연구)

  • Choi, Seung-Hyun;Choi, Boo-Byung;Choi, Dae-Gyun
    • The Journal of Korean Academy of Prosthodontics
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    • v.29 no.1
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    • pp.53-71
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    • 1991
  • This study was performed to investigate the muscular activity of the complete denture wearers compare with subjects with natural teeth. For the study, 10 subjects with natural dentition and 18 upper and lower complete denture wearers selected and the Bio-electric Processor EM2(Myo-tronics Reaserch, Inc., U.S.A.) with the surface electrodes was used to record electromyographic activity from the right and left middle of masseter and anterior temporal muscles of each subject during mandibular postural rest position, tapping of teeth from postural rest position, maximal clench, and right and left gum and raw carrow chewing. This results of this study were as follows : 1. In mandibular postural rest position, the denture wearers produces high muscular activity in contrast to natural objects(P<0.05) but, there was no difference between the state of denture removal and insertion, and the muscle activity of the anterior temporal muscle was high than the middle of masseter muscle in natural objects and denture wearers. 2. In tapping of teeth, there was no difference in muscle activity between natural objects and the state of denture removal of denture wearers. 3. In maximal clench, there was markedly lower denture wearers than natural objects in muscle activity, and the ratio of mean voltages was about 36 percentages. 4. In gum and raw carrow chewing, the activity was lower than natural object, the ratio was about 59 percentages. 5. In chewing, the mean voltages of the middle of masster muscle on the chewing side was highest, followed by the anterior temporal on the chewing side, the anterior temporal and masster muscles on the non-chewing side.

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Effect of Sex and Menopausal Age on Thickness and Density of Membranous Bone : Focused on Computed Tomography in Squamous Portion of Temporal Bone (성별과 폐경기 나이가 막성골의 두께와 밀도에 미치는 영향 : 측두골 비늘부위 전산화단층영상을 중심으로)

  • Ji, Myeong-Hoon;Seoung, Youl-Hun
    • Journal of radiological science and technology
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    • v.44 no.3
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    • pp.211-218
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    • 2021
  • The purpose of this study was to investigate the effect of sex and menopausal age on the thickness and density of squamous portion of the temporal bone as the membranous bone. Patients who visited a general hospital in Chungnam and had a computed tomography (CT) examination of the head. A retrospective study was conducted with 120 subjects (30 men under 55 years old, 30 men over 56 years old, 30 women under 55 years old, and 30 women over 56 years old). Axial images of the squamous portion in the temporal bone were obtained from CT of the head. For this image, a slice sensitive profile (SSP) was acquired with an image analysis program and these were evaluated. The thickness was measured by using a digital ruler to measure the full width at half maximum (FWHM) of the SSP, and the density was measured in hounsfield unit (HU). These by gender were measured to be about 0.5 mm thinner in the temporal bone in men than in women, and there was a significant difference. The density was measured to be about 200 HU higher in women than in men of it, and there was a significant difference. As a result, it in women was thicker and had a lower density. The thickness of it in men and women over 56 years of age was 0.8 mm or more thicker in women and less than 400 HU in density. As a result, the women group over the age of 56 showed a distinct increase in thickness and decrease in density, different from other target groups. It is expected that the results of this study could be used as basic data for a new bone density measurement site study.

Gender Differences in Heat Pain and Temporal Summation Threshold in Normal Volunteers (정상 자원자에서 열통증과 시간적 가중 역치에 대한 남녀 차이)

  • Lee, Joon Ho;Yoo, Jae Hwa;Cho, Sung Hwan;Kim, Yong Ik
    • The Korean Journal of Pain
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    • v.21 no.2
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    • pp.126-130
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    • 2008
  • Background: Females generally have a lower pain and temporal summation threshold than men. However, the results of studies designed to evaluate gender differences in the thresholds of heat pain and the temporal summation have been inconsistent. Newly developed device, CHEPS (Contact Heat Evoked Potential Stimulation) model of PATHWAY, have superiority on its fast rise and return time in temperature. Therefore we investigated gender differences in heat pain and temporal summation threshold. Methods: Forty healthy volunteers (20 males and 20 females) were enrolled in this study. A thermode was applied to the volar side of each volunteer's left forearm and heat pain and the temporal summation threshold was then measured. The heat pain threshold was estimated using the staircase method by starting from $36^{\circ}C$ and then increasing the temperature in $0.5^{\circ}C$ increments. The temporal summation threshold was estimated by applying five successive stimulation of the same temperature starting at $2^{\circ}C$ lower than the heat pain threshold and then increasing the temperature in $0.5^{\circ}C$ increments. Results: The mean heat pain thresholds was found to be $41.63{\pm}1.63^{\circ}C$ for males and $41.60{\pm}1.84^{\circ}C$ for females and the temporal summation thresholds were found to be $40.83{\pm}1.64^{\circ}C$ for males and $40.77{\pm}1.93^{\circ}C$ for females. The differences between males and females were not statistically significant. Conclusions: The result of this study suggested that there are no gender differences in heat pain and temporal summation threshold.

Research for Temporal·Spatial Parameter of the Gait According to Age (연령에 따른 보행의 시간적·공간적 요소에 관한 연구)

  • Chae, Jung-Byung;Kong, Seung-Whan;Kim, Dong-Jae;Kim, La-Jin;Kim, Tae-Young;Lee, Seung-Hoo
    • PNF and Movement
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    • v.6 no.2
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    • pp.19-30
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    • 2008
  • Purpose : This study was performed for find out temporal spatial parameter of the gait according to age. Method : Four groups of healthy people were allocated randomly in this study : group I(little child, 15), group II(child, 18) and group III(young people, 17), group(elder people, 16). This study was performed from 01 December to 31 December in 2007. Results : The results were as follows : 1. The swing phase was the longest group II, group IV was the shortest. Each groups, there was significant difference in swing phase(p<.05). 2. The stance phase was the longest group IV, group II was the shortest. Each groups, there was significant difference in stance phase(p<.05). 3. The single support time was the longest group II, group IV was the shortest. Each groups, there was significant difference in single support time(p<.05). 4. The double support time was the longest group IV, group II was the shortest. Each groups, there was significant difference in double support time(p<.05). 5. The gait velocity was the fastest group II, group I was the slowest. Each groups, there was significant difference in gait velocity(p<.05). 6. The toe in/out was very increased group IV, group I was very decreased. Each groups, there was significant difference in toe in/out(p<.05). 7. The cadence was the highest group I, group IV was the lowest. Each groups, there was significant difference in cadence(p<.05). 8. The step length was the longest group III, group I was the shortest. Each groups, there was significant difference in step length(p<.05). 9. The step length asymmetry ratio was the highest group IV, group III was the lowest. Each groups, there was no significant difference in step length asymmetry ratio(p>.05). 10. The single support time asymmetry ratio was the highest group I, group IV was the lowest. Each groups, there was no significant difference in single support time asymmetry ratio (p>.05). 11. The FAP was the highest group III, group I was the lowest. Each groups, there was significant difference in FAP(p<.05).

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A Study on the Masticatory Muscle Activity According to the Occlusal Guidance Patterns (교합 유도 형태에 따른 저작근 활성도에 관한 연구)

  • Kim, Ok-Hee;Kay, Kee-Sung
    • The Journal of Korean Academy of Prosthodontics
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    • v.27 no.2
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    • pp.189-200
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    • 1989
  • The purpose of this study was to investigate the muscle activity of the group function occlusion and the changed canine guided occlusion using EM2. In this study, 13 subjects with group function occlusion and without temporomandibular disorders were selected, each subject was changed to the canine guided occlusion by forming the lingual ramps in the upper canines with light curing composite resin. The muscle activities of the anterior temporal and masseter muscle were recorded in the group function occlusion and immediately, one week, and two weeks after changing to the canine guided occlusion under the condition of maximum voluntary clenching in centric occlusion, lateral excursion, and during gum chewing. The results were as follows: 1. In case of maximum voluntary clenching in centric occlusion, the muscle activities of the anterior temporal and masseter muscle of working and balancing side didn't show any difference immediately after changing to the canine guided occlusion, one week after changing to the canine guided occlusion, one week after changing to it the muscle activities of the anterior temporal masseter muscle of working and balancing side were increased significantly, and two weeks after changing to it the muscle activities of the masseter muscle were increased significantly in comparison with the group function occlusion. 2. In case of maximum voluntary clenching in lateral excursion, the muscle activities of the anterior temporal and masseter muscle of working and balancing side were reduced significantly immediately after changing to the canine guided occlusion, one week after changing to it the muscle activities of the anterior temporal muscle of balancing side and of the anterior temporal and masseter muscle of working side were reduced significantly, and 2 weeks after changing to it the muscle activities of the anterior temporal and masseter muscle of working side were reduced significantly in comparison with the .group function occlusion. 3. During gum chewing, the muscle activities of the anterior temporal and masseter muscle of working and balancing side didn't show any difference immediately after changing to the canine guided occlusion, one week after changing to it the muscle activities of the masseter muscle of working and balancing side were increased significantly, and two weeks after changing to it only the muscle activities of masseter muscle of working side were increased significantly.

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Comparison of Three Land Cover Classification Algorithms -ISODATA, SMA, and SOM - for the Monitoring of North Korea with MODIS Multi-temporal Data

  • Kim, Do-Hyung;Jeong, Seung-Gyu;Park, Chong-Hwa
    • Korean Journal of Remote Sensing
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    • v.23 no.3
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    • pp.181-188
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    • 2007
  • The objective of this research was to investigate the optimal land cover classification algorithm for the monitoring of North Korea with MODIS multi-temporal data based on monthly phenological characteristics. Three frequently used land cover classification algorithms, ISODATA1), SMA2), and SOM3) were employed for this study; the land cover categories were forest, grass, agricultural, wetland, barren, built-up, and water body. The outcomes of the study can be summarized as follows. First, the overall classification accuracy of ISODATA, SMA, and SOM was 69.03%, 64.28%, and 73.57%, respectively. Second, ISODATA and SMA resulted in a higher classification accuracy of forest and agricultural categories, but SOM performed better for the built-up area, bare soil, grassland, and water. A possible explanation for this difference would be related to the difference of sensitivity against the vegetation activity. This would be related to the capability of SOM to express all of their values without any loss of data by maintaining the topology between pixels of primitive data after classification, while ISODATA and SMA retain limited amount of data after normalization process. Third, we can conclude that SOM is the best algorithm for monitoring the land cover change of North Korea.