• Journal of Electrical Engineering and information Science
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• v.2 no.6
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• pp.131-137
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• 1997

In this paper, we propose an efficient motion adaptive 3-dimensional (3D) video coding algorithm using 3D subband coding (3D-SBC) and lattice vector quantization (LVQ) for low bit rate. Instead of splitting input video sequences into the fixed number of subbands along the temporal axes, we decompose them into temporal subbands of variable size according to motions in frames. Each spatio-temporally splitted 7 subbands are partitioned by quadtree technique and coded with lattice vector quantization(LVQ). The simulation results show 0.1∼4.3dB gain over H.261 in peak signal to noise ratio (PSNR) at low bit rate(64Kbps).

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.4 no.3
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• pp.266-270
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• 2004

The image interpolation is one of an image preprocessing process to heighten a resolution. The conventional image interpolation used much to concept that it put in other pixel to select the nearest value in a pixel simply, and use much the temporal object interpolation techniques to do the image interpolation by detecting motion in a moving picture presently. In this paper, it is proposed the image interpolation techniques using the fuzzy wavelet base function. This is applied to embody a correct edge image and a natural image when expand part of the still image by applying the fuzzy wavelet base function coefficient to the conventional B-spline function. And the proposal algorithm in this paper is confirmed to improve about 1.2831 than the image applying the conventional B-spline function through the computer simulation.

• 전기의세계
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• v.21 no.5
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• pp.7-12
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• 1972

Applying the theory of physiology and control systems, the visual system was studied as a regulator of impining light. The characteristics function of visual system is mainly analysed by spato-temporal characteristics based upon Enroth's model, Broca-Sulzer phenomenon and Mach effect. Some aims of this paper are as follows. (1) In order to get the excitatory and inhibitory potential of the intermediated cell layer in the retina, the exponential value, {exp(FM/kT)- $I_{mn}$ } is caculated based on the physiological theory in neuro-phenomena. (2) To show the visual characteristics by analog simulation for generating stimulus waveforms and analysis, the visual adaptation was recorded as electrical stimulation in the form of step functions. Furthermore, ti is shown that the above experimental data agrees satisfactorily with the theoretical (psychophysiological) values. This study is expected to lead to further studies concerned with human observer and human operator in control and especially pattern recognition systems.stems.

• Journal of Satellite, Information and Communications
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• v.12 no.2
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• pp.65-70
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• 2017

The structure of MMSE receiver front-ended by CMA(Constant Modulus Array) array working in CDMA forward link which is applicable to LEO spread spectrum satellite communication system is proposed. By using the despreaded pilot signal of forward link as a reference signal, the CMA array can capture multi-path signals securely even in severely faded LEO satellite channel. The remaining MAI (Multiple Access Interference) is cancelled by the cascaded MMSE receiver. Besides theoretical development, through relevant computer simulation, it is proved that the proposed system shows much better BER performance than any other possible candidate systems. As a spatio-temporal receiver mounted on a mobile vehicle, the proposed system also reduces implemental cost and complexity by adopting the simplest algorithm for its spatial and temporal domain processing.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.266-268
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• 2003

This is based on the AGENT-LUC model framework. Luangprabang Province has the largest percentage of shifting cultivation area in Laos PDR. The model simulates the spatial and temporal patterns of the shifting cultivation in the study area, using a GIS database while the total area of shifting cultivation is controlled by supply and demand balance of food. The model simulation period is from 1990 to 1999, at a spatial resolution of 500m. The results are evaluated using statistical data and remote sensing images. Through the validation, it is concluded that the trends simulated agrees to that of statistical data and the spatial and temporal patterns are also replicated satisfactorily.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.253-253
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• 2015

This research evaluated the effect of two main sources on the results of the ocean regional circulation model (ORCMs) during downscaling and nesting the results from the coarse data. The two sources should be the domain size, and temporal and spatial resolution different between driving and driven data. The Big-Brother Experiment is applied to examine the impact of them on the results of the ORCMs separately. Within resolution of 3km grid point ORCMs applying in the Big-Brother Experiment framework, it showed that the simulation results of the ORCMs depend on the domain size and specially the spatial and temporal resolution of lateral boundary conditions (LBCs). The domain size can be selected at 9.5 times larger than the interest area, and the spatial resolution between driving data and driven model can be up to 3 of ratio resolution and updating frequency of the LBCs can be up to every 6 hours per day.

• Journal of Information Processing Systems
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• v.20 no.1
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• pp.131-147
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• 2024

A routing strategy based on traffic prediction and dynamic cache allocation for satellite nodes is proposed to address the issues of high propagation delay and overall delay of inter-satellite and satellite-to-ground links in low Earth orbit (LEO) satellite systems. The spatial and temporal correlations of satellite network traffic were analyzed, and the relevant traffic through the target satellite was extracted as raw input for traffic prediction. An improved gradient boosting regression tree algorithm was used for traffic prediction. Based on the traffic prediction results, a dynamic cache allocation routing strategy is proposed. The satellite nodes periodically monitor the traffic load on inter-satellite links (ISLs) and dynamically allocate cache resources for each ISL with neighboring nodes. Simulation results demonstrate that the proposed routing strategy effectively reduces packet loss rate and average end-to-end delay and improves the distribution of services across the entire network.

• Journal of Broadcast Engineering
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• v.16 no.5
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• pp.873-882
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• 2011

In this paper, we propose an efficient deinterlacing algorithm which interpolates the missing scan lines by weighted summing of the intra and the inter interpolation pixels according to the spatio-temporal variation. In the spatial interpolation, we adopt a new edge based spatial interpolation method which includes edge directional refinement. The conventional edge dependent interpolation algorithms are very sensitive to noise due to the failure of estimating edge direction. In order to exactly detect edge direction, our method first finds the edge directions around the pixel to be interpolated and then refines edge direction of the pixel using weighted maximun frequent filter. Futhermore, we improve the accuracy of motion detection by reducing the possibility of motion detection error using 3 tab median filter. In the final interpolation step, we adopt weighted sum of intra and inter interpolation pixels according to spatio-temporal variation ratio, thereby improving the quality in slow moving area. Simulation results show the efficacy of the proposed method with significant improvement over the previous methods in terms of the objective PSNR quality as well as the subjective image quality.

• Ocean and Polar Research
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• v.25 no.3
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• pp.237-247
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• 2003

The temporal dynamics of the meiofauna community in Marian Cove, King George Island were observed from January 22 to October 29 1996. Generally, 14 taxa of metazoan meiofauna were found. Nematodes were dominant comprising 90.12% of the community, harpacticoid 6.55%, and Kinorhynchs 1.54%. Meiofauna abundance increased monthly from January to May 1996, while varying in abundance after August 1996. Overall mean abundance of metazoan meiofauna was $2634ind./10cm^2$ during the study periods, which is about as high as that found in temperate regions. Nematodes were most abundant representing $2399ind./10cm^2$. Mean abundance of harpacticoids, including copepodite and nauplius was $131ind./10cm^2$ by kinorhynchs $(26ind./10cm^2)$. The overall abundance of other identified organisms was $31ind./10cm^2$ Other organisms consisted of a total of 11 taxa including Ostracoda $(6ind./10cm^2)$, Polycheata $(7ind./10cm^2)$, Oligochaeta $(8ind./10cm^2)$, and Bivalvia $(6ind./10cm^2)$. Additionally, protozoan Foraminifera occurred at the study area with a mean abundance of $263ind./10cm^2$. Foraminiferans were second in dominance to nematodes. The dominant taxa such as nematodes, harpacticoids, kinorhynchs and the other tua were trained and extensively scattered in the map through the Kohonen network. The temporal pattern of the community composition was most affected by the abundance dynamics of kinorhynchs and harpacticoids. The neural network model also allowed for simulation of data that was missing during two months of inclement weather. The lowest meiofauna abundance was found in August 1996 during winter. The seasonal changes were likely caused by temperature and salinity changes as a result of meltwater runoff, and the physical impact by passing icebergs.

• Journal of Broadcast Engineering
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• v.7 no.4
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• pp.300-309
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• 2002

The object of this paper is to make temporal direct mode clear by providing a solution to the following problem : if the co-located block in the list 1 reference picture for direct mode has only the 1ist 1 motion vector or both the 1ist 0 and list 1 motion vectors, then which motion vector will be used for the direct mode motion vector calculation\ulcorner This paper also shows how to derive reference picture index and direct mode motion vector for each list in order to guarantee the high coding efficiency. when the co-located macroblock is in intra mode. Furthermore, the reasonable calculation methods for the direct mode motion vectors in the various cases are presented. Finally, experimental results show that the proposed temporal direct mode provides the comparable performance against the spatial direct mode. Therefore, the simulation proves that the proposed temporal direct mode is acceptable.