• Journal of applied mathematics & informatics
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• v.39 no.5_6
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• pp.655-676
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• 2021

A parameter uniform numerical scheme is proposed for solving singularly perturbed parabolic partial differential-difference convection-diffusion equations with a small delay and advance parameters in reaction terms and spatial variable. Taylor's series expansion is applied to approximate problems with the delay and advance terms. The resulting singularly perturbed parabolic convection-diffusion equation is solved by utilizing the implicit Euler method for the temporal discretization and finite difference method for the spatial discretization on a uniform mesh. The proposed numerical scheme is shown to be an ε-uniformly convergent accurate of the first order in time and second-order in space directions. The efficiency of the scheme is proved by some numerical experiments and by comparing the results with other results. It has been found that the proposed numerical scheme gives a more accurate approximate solution than some available numerical methods in the literature.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.4
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• pp.352-356
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• 2010

In this study, it is discussed how the directional property of the sound lateralization is influenced by proceeding or succeeding tone. The acoustic source applied here is a reference sound which has 0.5 msec interaural time difference(ITD). Based on this reference sound, interfering sounds with five levels of magnitude are applied to the subjects with four kinds of inter-stimuli time intervals(ISI). The interfering sounds are also added as two different types, proceeding tone and succeeding tone. Additionally, in order to investigate a frequency influence, the reference sound and the interfering sounds are generated by using 2kHz, 4 kHz and a white noise. As a result, the influence on lateralization by proceeding tone is lager than that by succeeding tone. It can consider this result as the effect of temporal masking on lateralization. Moreover, there are small differences of masking effect on lateralization by combinations of pure tone. This result shows that the dependency of frequency domain between reference sound and interfering sound is small on the sound lateralization.

• Korean Journal of Biological Psychiatry
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• v.16 no.3
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• pp.159-169
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• 2009

Objectives : This study aimed to investigate the difference of brain activities in viewing a common emotional situation according to perspective-taking. Methods : Using fMRI, brain activities were measured while performing the task viewing a common emotional situation on either self-perspective or third-person perspective in fourteen healthy men. The relatively activated brain areas on each perspective were investigated, then the relationship between the activated brain regions and the scores of self report about some emotion or empathic ability were explored. Results : The relatively activated brain areas on self-perspective were bilateral paracentral lobule(BA 5), right postcentral gyrus(BA 3), right precentral gyrus(BA 4), left superior temporal gyrus(BA 22), left medial frontal gyrus(BA 6), whereas on third-person perspective right inferior frontal gyrus(BA 47), left caudate body and tail, right superior temporal gyrus(BA 38), right medial frontal gyrus(BA 8) were activated. The relative activity of left superior temporal gyrus on self-perspective was positively correlated with the score of Beck Depression Inventory. Conclusion : This study demonstrated that the activated brain region according to perspective-taking were different while viewing a common emotional situation. The depressive feeling would have an influence on the brain activity related to perspective-taking.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.243-245
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• 2007

This study was begun to classify the paddy fields by the rice varieties and to monitor the temporal change in rice growth using SAR backscatter coefficients $({\sigma}^{circ})$. For nine fine-beam mode images of Radarsat-1 SAR, a growing period time-series of backscatter coefficients was set up from April to October in 2005, and was compared with the field-measured rice growth parameters such as LAI (leaf area index), plant height, fresh and dry biomass, and water content in grain and plant for 45 parcels in Dangjin-gun, Chungcheongnam Province, South Korea. The average backscatter coefficients for early-maturing rice varieties (13 parcels) were ranged from -18.17dB to -6.06dB and were lower than for medium-late maturing rice varieties during most of the growing season. At around the heading stage (July 30) for early-maturing rice, both rice crops showed the highest backscatter coefficient values and the difference was the greatest before harvesting early-maturing rice. The temporal difference in backscatter coefficients between rice varieties was expected to play a key role to identify early-maturing rice fields. On the other hand, comparison with field-measured rice growth parameters showed that the backscatter coefficients decreased or stayed on the plateau after heading stage even though the growth of rice canopy advanced.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.22 no.3
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• pp.171-180
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• 2010

Analysis on the temporal variation of the stratification is carried out by using the continuous water temperature and salinity data observed in the coastal monitoring buoy in Mikawa Bay, Japan. The main analysis results are as follows. The stratification pattern have an obvious and dominant 1-year period variation and the occurrence frequency (days) are exponentially decreased as the stratification intensity (SI) defined as the density difference between surface and bottom layers linearly increases. The frequency distribution function of the SI is presumably close to the log-normal function type or exponential function type. From the water temperature and salinity scatter diagram analysis, the line and loop type patterns are shown in the bottom and surface layers, respectively. In addition, the analysis of the SI estimation show that the error bound in case of using the weekly-monitoring data is about 4.45 times greater than that in case of using the continuous (daily) monitoring data.

• Korean Journal of Community Nutrition
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• v.17 no.1
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• pp.109-118
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• 2012

This study was conducted to characterize changes in the meal structure of Korean children in terms of temporal and spatial dimensions. The data of 1,891 and 1,627 school-aged children and adolescents extracted respectively from the 1998 and 2009 Korea National Health and Nutrition Examination Surveys were analyzed by gender, age group, and residential area. From 1998 to 2009, the total eating events increased from 4.3 to 4.6 (p = 0.001); the average number of meal intake decreased from 2.8 to 2.7 (p < 0.001) while that of snack intake increased from 1.5 to 1.9 (p < 0.001). The prevalence of "3 meals a day" pattern tended to decrease while that of "2 meals a day" pattern increased over the years. Especially, the "2 meals a day" pattern with "lunch + dinner" increased from 13% in 1998 to 20% in 2009. The percentage of eating breakfast or dinner at home decreased over the years. These results indicate that over the last decade, "destructuration" occurred in Korean children's meal structure in terms of temporal and spatial dimensions. Especially, such alteration was more distinctive in male than female and in the high school-aged group than the elementary or middle school-aged groups. Overall, the difference of meal structure between genders and residential areas became smaller while the difference among age groups became larger over the years.

• Journal of Broadcast Engineering
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• v.10 no.3
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• pp.321-327
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• 2005

A MVC (Multi-view Video Coding) method, which uses both an illumination change-adaptive ME (Motion Estimation)/DC (Motion Compensation) and a 2D (Dimensional) direct mode, is proposed. Firstly, a new SAD (Sum of Absolute Difference) measure for ME/MC is proposed to compensate the Luma pixel value changes for spatio-temporal motion vector prediction. Illumination change-adaptive (ICA) ME/MC uses the new SAD to improve both MV (Motion Vector) accuracy and bit saving. Secondly, The proposed 2D direct mode that can be used in inter-view prediction is an extended version of the temporal direct mode in MPEG-4 AVC. The proposed MVC method obtains approximately 0.8dB PSNR (Peak Signal-to-Noise Ratio) increment compared with the MPEG-4 AVC simulcast coding.

• Journal of KIISE:Computer Systems and Theory
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• v.33 no.8
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• pp.536-546
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• 2006

Painterly animation is a method that expresses painterly images with a hand-painted appearance from a video, and the most crucial element for it is the temporal coherence of brush strokes between frames. A motion map is proposed in this paper as a solution to the issue of maintaining the temporal coherence in the brush strokes between the frames. A motion map is the region that frame-to-frame motions have occurred. Namely, this map refers to the region frame-to-frame edges move by the motion information with the motion occurred edges as a starting point. In this paper, we employ the optical flow method and block-based method to estimate the motion information. The method that yielded the biggest PSNR using the motion information (the directions and magnitudes) acquired by various methods of motion estimation has been chosen as the final motion information to form a motion map. The created motion map determine the part of the frame that should be re-painted. In order to express painterly images with a hand- painted appearance and maintain the temporal coherence of brush strokes, the motion information was applied to only the strong edges that determine the directions of the brush strokes. Also, this paper seek to reduce the flickering phenomenon between the frames by using the multiple exposure method and the difference map created by the difference between images of the source and the canvas. Maintenance of the coherence in the direction of the brush strokes was also attempted by a local gradient interpolation to maintain the structural coherence.

• Management & Information Systems Review
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• v.33 no.1
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• pp.99-118
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• 2014

This study is a product launch strategy Preannouncing companies associated with temporal distance( in the near future/ distant future) and prior knowledge level(high knowledge/ low knowledge), the memory - based judgments(Global product judgment/ Discrete product judgment) and the purchase intention appears, the difference between the empirical verification of what was discriminatory. The study, first, Preannouncing main effect of temporal distance on judgments remember the difference between the purchase intention and consistent global product judgment is more discrete product judgment were higher awareness, purchase intention is higher. Second, Preannouncing high level of product knowledge in global product judgment showed that compared to discrete product judgment. In addition, low levels of knowledge than a discrete product judgment that global product judgment and purchase intention shown that a high level of consumer knowledge through systematic information processing and the road leads to higher purchase attitude. Third, Preannouncing according to the temporal distance and level of knowledge about the interaction effect results in the near future in terms of the high level of knowledge consumers global product judgment was higher than the discrete product judgment. On the other hand, a low level of knowledge of conditions in the distant future, consumers are more discrete product judgment recognized global product judgment showed that high.

• The Journal of Korean Academy of Prosthodontics
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• v.36 no.4
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• pp.598-614
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• 1998

This study was performed to investigate the influence of lateral guidance pattern and chewing pattern on masticatory muscle activity and occlusal contact pattern. Twenty-five patients with temporomandibular disorders and thirty students without temporomandibular disorders were selected for this study. Electromyographic examination and occlusal contact examination were performed simultaneously with Bio-Pak System (Bioresearch Inc.,U.S.A.) and T-Scan System(Tekscan Co., USA). The obtained results were as follows : 1. The EMG activity of masseter and anterior temporal muscle in patient group with canine guidance was higher than with non-canine guidance. but there was no significant difference (p>0.05). 2. The EMG activity of anterior temporal muscle in normal group with non-canine guidance was higher at preferred chewing side than at opposite side (p<0.05). 3. The EMG activity of masseter muscle was higher in normal group than in patient group (p<0.05). 4. The number of occlusal contact in patient group with canine guidance was higher than with non-canine guidance, but there was no significant difference (p>0.05). 5. The occlusal contact force at preferred chewing side was higher in patient group than in normal group(p<0.05).