• Journal of Broadcast Engineering
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• v.17 no.1
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• pp.165-178
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• 2012

In most conventional video codecs, such as MPEG-2 and MPEG-4, inter coding is performed with the fixed motion vector resolution. When KTA software was developed, resolution for MVs can be selected in each slice. Although KTA codec uses a variety of resolutions for ME, the selected resolution is applied over the entire pixels in the slice and the statistical property of the local area is not considered. In this paper, we propose an adaptive decision scheme for motion vector resolution which depends on region, where MV search area is divided to multiple regions according to the distance from PMV. In each region, the assigned resolution is used to estimate MV. Each region supports different resolution for ME from other regions. The efficiency of the proposed scheme is affected from threshold values to divide the search area and the entropy coding method to encode the estimated MV. Simulation results with HM3.0 which is the reference software of HEVC show that the proposed scheme provides bit rate gains of 0.9%, 0.6%, and 2.9% in Random Access, Low Delay with B picture, and Low Delay with P picture structures, respectively.

• Journal of Korea Technology Innovation Society
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• v.11 no.2
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• pp.264-286
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• 2008

In 2006, the share of energy in Korea amounted to 28% from the total import, 97% from overseas dependency, and 83% for the national Greenhouse Gas (GHG) emission in 2004. Thus, from the aspects of economical and environmental policies, an energy analysis is very important, for the industry to cope with the imminent pressure for climate change. However, the estimation of GHG gas emissions due to an energy use is still done in a primitive way, whereby each industry's usage is multiplied by coefficients recommended from international organizations in Korea. At this level, it is impossible to formulate the prevailing logic and policies in face of a new paradigm that seeks to force participation of developing countries through so called post-Kyoto Protocol. In this study, a hybrid energy input-output (E-IO) analysis is conducted on the basis of the input-output(IO) table of 2000 issued by the Bank of Korea in 2003. Furthermore, according to economic sectors, emission of the GHG relative to an energy use is characterized. The analysis is accomplished from four points of view as follows: 1) estimating the GHG emission intensity by 96 sectors, 2) measuring the contribution ratio to GHG emissions by 14 energy sources, 3) calculating the emission factor of 3 GHG compounds, and 4) estimating the total amount of national GHG emission. The total amount estimated in this study is compared with a national official statistical number. The approach could be an appropriate model for the recently spreading concept of a Life Cycle Analysis as it analyzes not only a direct GHG emission from a direct energy use but also an associated emission from an indirect use. We expect this model can provide a form for the basis of a future GHG reduction policy making.

• Journal of KIISE
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• v.42 no.5
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• pp.609-620
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• 2015

Viewers of videos are likely to absorb more information from the part of the screen that attracts visual attention. This fact has led to the visual attention models that are being used in producing and evaluating videos. In this paper, we investigate the factors that are significant to visual attention and the mathematical form of the visual attention model. We then estimated the visual attention probability using the statistical design of experiments. The analysis of variance (ANOVA) verifies that the motion velocity, distance from the screen, and amount of defocus blur affect human visual attention significantly. Using the response surface modeling (RSM), we created a visual attention score model that concerns the three factors, from which we calculate the visual attention probabilities (VAPs) of image pixels. The VAPs are directly applied to existing gradient based 3D effect perception measurement. By giving weights according to our VAPs, our algorithm achieves more accurate measurement than the existing method. The performance of the proposed measurement is assessed by comparing them with subjective evaluation as well as with existing methods. The comparison verifies that the proposed measurement outperforms the existing ones.

• Korean Journal of Remote Sensing
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• v.31 no.6
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• pp.513-521
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• 2015

In the processing of ocean color remote sensing data, spatio-temporal binning is crucial for securing effective observation area. The validity determination for given source data refers to the information in Level-2 flag. For minimizing the stray light contamination, NASA OBPG's standard algorithm suggests the use of large filtering window but it results in the loss of effective observation area. This study is aimed for quality improvement of ocean color remote sensing data by recovering/extending the portion of effective observation area. We analyzed the difference between MODIS/Aqua standard and modified product in terms of chlorophyll-a concentration, spatial and temporal coverage. The recovery fractions in Level-2 swath product, Level-3 daily composite product, 8-day composite product, and monthly composite product were $13.2({\pm}5.2)%$, $30.8({\pm}16.3)%$, $15.8({\pm}9.2)%$, and $6.0({\pm}5.6)%$, respectively. The mean difference between chlorophyll-a concentrations of two products was only 0.012%, which is smaller than the nominal precision of the geophysical parameter estimation. Increase in areal coverage also results in the increase in temporal density of multi-temporal dataset, and this processing gain was most effective in 8-day composite data. The proposed method can contribute for the quality enhancement of ocean color remote sensing data by improving not only the data productivity but also statistical stability from increased number of samples.

• Journal of Korean Society of Transportation
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• v.24 no.5 s.91
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• pp.57-66
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• 2006

This paper presents new pedestrian signal timings considering pedestrian demand Pedestrian characteristics, and land use which were obtained by Pedestrian characteristics field survey and pedestrian signal operation survey. Pedestrian signal timings suggested were compared to the existing pedestrian signal timings by using real field data. pedestrian characteristics field survey was conducted to collect pedestrian crossing speed data and reaction time data. Sixteen areas in Seoul were selected for the data collection. The average pedestrian crossing speed was 1.30m/sec and the 15th Percentile speed was 1.11m/sec. The average reaction time was 2.24 seconds. Pedestrian crossing speed differs by land use, road width. pedestrian age, sex, and number of Pedestrians. Reaction time also differs by road width, pedestrian age, and number of pedestrians. Statistical testing was performed to secure reliability of the collected data.

• Journal of Korean Society of Transportation
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• v.28 no.5
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• pp.55-64
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• 2010

In order to prepare an efficient solution for PM10 reduction in underground stations, the authors measured PM10 concentration levels every 30 minutes in the concourse, platform, and tunnel of Gaehwasan Station of Seoul's subway line 5. Through a correlation analysis of each changing pattern of PM10 concentration, the direction and velocity of diffusion in underground stations were estimated. The PM10 concentration levels were highest in the tunnel, followed by the platform and concourse. PM10 concentrations in the tunnel, platform, and concourse showed a pattern of increasing in the rush hours and decreasing in the non-rush hours. According to the statistical analysis of PM10 concentrations and changing patterns in each location, the higher PM10 concentration in the tunnel expanded to the platform, and some from the platform expanded to the concourse. Therefore, to efficiently reduce PM10 concentrations, it is essential to detect the centralized generation, diffusion factor, expanding route, expanding measure, and other variables and to remove or reduce the diffusion factor and level. Through operating the ventilation system in the right time frame while the PM10 concentration level increases, the power consumption and peak power consumption can be reduced.

• Journal of Korean Society of Transportation
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• v.31 no.5
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• pp.71-78
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• 2013

This paper investigated the influences of ramp traffic flow on the lane utilization for signalized intersection approaches which are adjacent to an off-ramp-street junction. The statistical test showed a correlation between lane utilization and the ramp traffic flow. As the ramp traffic flow increases, the left lanes are less utilized and the right lanes are more utilized. The lane utilization factors are calculated by applying traffic data collected from the Seoul Metropolitan area. The utilization factors are 1.113 for 2 lanes, 1.124 for 3 lanes, and 1.131 for 4 lanes. The lane utilization factors proposed in the paper show higher values than those in current Korea Highway Capacity Manual (KHCM) under the conditions that the number of lanes is 2 or 3. However, the lane utilization factor for 4 lanes in the paper shows lower value than in KHCM. The ramp traffic flow causes more utilization of the right lanes than at normal signalized intersections and the extent gets larger as the number of lanes decreases. Based on the results of the paper, the lane utilization factors at signalized intersection approaches should be revised and reasonable capacity should be recalculated if the signalized intersection is adjacent to an off-ramp-street junction.

• Journal of the Earthquake Engineering Society of Korea
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• v.12 no.4
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• pp.1-10
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• 2008

Shear wave velocity($V_S$), which can be obtained using various seismic tests, has been emphasized as representative geotechnical dynamic characteristic mainly for seismic design and seismic performance evaluation in the engineering field. For the application of conventional geotechnical site investigation techniques to geotechnical earthquake engineering, standard penetration tests(SPT) and piezocone penetration tests(CPTu) together with a variety of borehole seismic tests were performed at many sites in Korea. Through statistical modeling of the in-situ testing data, in this study, the correlations between $V_S$ and geotechnical in-situ penetrating data such as blow counts(N value) from SPT and piezocone penetrating data such as tip resistance ($q_t$), sleevefriction($f_s$), and pore pressure ratio($B_q$) were deduced and were suggested as an empirical method to determine $V_S$. Despite the incompatible strain levels of the conventional geotechnical penetration tests and the borehole seismic tests, it is shown that the suggested correlations in this study are applicable to the preliminary estimation of $V_S$ for Korean soil layers.

• Korean Journal of Remote Sensing
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• v.20 no.2
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• pp.91-102
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• 2004

This paper reflects the estimation of using the EOC(Electro-optical Camera) images supporting GIUH(geomorphological instantaneous unit hydrograph) approach. We have analyzed GIUH in its density and frequency distribution by creating a DEM(digital elevation model) for the sub basin produced from the EOC images and examined topographical and hydrological application possibility of the EOC images. In this process, we have topographical basin characteristic analysis that use the remote sensing technique analyzing the DEM creation process of the EOC stereo images by studying the basic topographical hydrology analysis about abstraction technique since it is flirty complex and is more time-consuming than other method. we executed statistical analysis of a basin size and river length using the frequency function after divided lattice spacing applied have to the sub river basin from the image data and the digital map into 10m intervals ranging from 10m to 100m. After comparing and examining the peak and time to peak of the GIUH, we proceeded with a comparative analysis by lattice concerning the topographical divergence rate, area ratio, length ratio. Accumulating the peak and time to peak of the GIUH is altered to non-linear form in accordance to lattice dimension as well as basin factor. It was proved that the lattice dimension is one of the important factors about the peak and time to peak of the GIUH.

• Journal of Sericultural and Entomological Science
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• v.3
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• pp.61-67
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• 1963

This report is prepared to find how the filament of cocoon bave size deviation relates with the raw silk made by them which are intensively cultured in this country. Three recommended hybrid varieties and two varieties under working at Suwon Sericultural Experiment Station were selected as specimens. The cocoons were reeled as an individual filament of every fifty meters long skein with a wrap reel to weigh the denier and to investigate the relationship of the above statement so that it may be used for the quality estimation before processing it into raw silk. The conclusions obtained are as follows. (1) The variation of Pk${\times}$Sn was found as best cocoon for 21 denier raw silk use, but the number of cocoon to make the denier has to be eight which might cause more labor cost. (2) Baektoo-Kumkang and Myohiang-Chongchon were found as economical varieties for 21 denier use. (3) Seulak-Soyang is a proper variety for the use of 14 or 28 denier silk use. (4) Myohiang-Chongchon did not confirm a good property from the aspect of denier deviation. (5) It was found that there was a fairly strong corelationship between the mean cocoon bave size deviation as indicated by Ono's report. (6) Three graphs were prepared to estimate the cocoon quality before processing into various sizes of raw silk using the mean cocoon bave size and the raw silk size to be prepared. (7) Mean time, the graph which is able to estimate the expectable grade of the raw silk size deviation was designed for the practical use. (8) The expectable grade of the varieties used in this report were found as following data. Notice (A......cocoon number to make raw silk (B......total cocoon bave size deviation (C......expectable silk grade (9) The result of the work concerning the expectable denier deviation on 21 denier silk was the same with the statistical actual testing result as 1.25 D while the distribution showed farther necessity of improvement in technically.