• International Journal of Highway Engineering
• /
• v.17 no.4
• /
• pp.135-141
• /
• 2015

PURPOSES: This study has been conducted to determine a homogeneous segment and integration to improve the efficiency of short-term traffic count. We have also attempted to reduce the traffic monitoring budget. METHODS: Based on the statistical approach, a homogeneous segment in the same road section is determined. Statistical analysis using t-test, mean difference, and correlation coefficient are carried out for 10-year-long (2004-2013) short-term count traffic data and the MAPE of fresh data (2014) are evaluated. The correlation coefficient represents a trend in traffic count, while the mean difference and t-score represent an average traffic count. RESULTS : The statistical analysis suggests that the number of target segments varies with the criteria. The correlation coefficient of more than 30% of the adjacent segment is higher than 0.8. A mean difference of 36.2% and t-score of 19.5% for adjacent segments are below 20% and 2.8, respectively. According to the effectiveness analysis, the integration criteria of the mean difference have a higher effect as compared to the t-score criteria. Thus, the mean difference represents a traffic volume similarity. CONCLUSIONS : The integration of 47 road segments from 882 adjacent road segments indicate 8.87% of MAPE, which is within an acceptable range. It can reduce the traffic monitoring budget and increase the count to improve an accuracy of traffic volume estimation.

• Journal of Korea Water Resources Association
• /
• v.30 no.6
• /
• pp.611-620
• /
• 1997

The history of Tidal Bench Mark(TBM) at four major tide observation stations on the the Korea West Coast is reviewed. The data concerned with the local mean sea level(LMSL), the datum level(DL), and TBM is collected and checked. The values of LMSL surveyed by Rural Development Corporation(RDC), Office of Hydrographic Affair(OHA), and Office of Port Affair(OPA) are compared so that their unbiased MSLs at four stations are determined. Kriging model is introduced to estimate the design levels for tide; DL, MSL, and high water spring tide(HWOST). The estimated design level is well fitted with the sample data. The value of the identified drifts increase with the latitude. The estimated semi-variograms ${\gamma}(h)$ show self similarity. The values of the ${\gamma}(h)$ for DL and HWOST are 0.005 times as much as the values of ${\gamma}(h)$ of MSL.

• The Journal of the Korea Contents Association
• /
• v.14 no.6
• /
• pp.93-107
• /
• 2014

Recently Korean film industry has continuously experienced a rapid growth and expanded its influence to foreign countries. Accordingly, there have been numerous studies in various research areas to investigate the characteristics of the industry. In this study, we applied social network analysis based on the attributes such as genres, ratings, distributors, nationalities, sizes, and profitability to divide the movies into several clusters with respect to their similarity. Results suggested that the ratings and nationality rather than the genre are the major factors to divide the motion picture market into clusters and the profitability also varies much across the clusters. Furthermore, estimation of the diffusion model showed the positive relationship between the success of a movie and the word-of-mouth effect, while the relatively unsuccessful titles exhibited a monotonic decreasing diffusion pattern with the high initial demand and the early peak time.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.37 no.4
• /
• pp.37-45
• /
• 2000

In this paper we suggest a method of detecting the two eyes position of moving viewer by using images obtained through a color CCD camera, and also a method of rendering view-dependent 3D image which consists of depth estimation, image-based 3D object modeling and stereoscopic display process. Through the experiment of applying the suggested methods, we could find the accurate two-eyes position with the success rate of 97.5% within the processing time of 0.39 second using personal computer, and display the view-dependent 3D image using Fl6 flight model. And through the similarity measurement of stereo image rendered at z-buffer by Open Inventor and captured by stereo camera using robot, we could find that view-dependent 3D picture obtained by our proposed method is optimal to viewer.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.9 no.6
• /
• pp.2230-2250
• /
• 2015

Multiple projectors with partially overlapping regions can be used to project a seamless image on a large projection surface. With the advent of high-resolution photography, such systems are gaining popularity. Experts set up such projection systems by subjectively identifying the types of errors induced by the system in the projected images and rectifying them by optimizing (correcting) the parameters associated with the system. This requires substantial time and effort, thus making it difficult to set up such systems. Moreover, comparing the performance of different multi-projector display (MPD) systems becomes difficult because of the subjective nature of evaluation. In this work, we present a framework to quantitatively determine the quality of an MPD system and any image projected using such a system. We have divided the quality assessment into geometric and photometric qualities. For geometric quality assessment, we use Feature Similarity Index (FSIM) and distance-based Scale Invariant Feature Transform (SIFT). For photometric quality assessment, we propose to use a measure incorporating Spectral Angle Mapper (SAM), Intensity Magnitude Ratio (IMR) and Perceptual Color Difference (ΔE). We have tested the proposed framework and demonstrated that it provides an acceptable method for both quantitative evaluation of MPD systems and estimation of the perceptual quality of any image projected by them.

• Korean Journal of Soil Science and Fertilizer
• /
• v.30 no.3
• /
• pp.209-225
• /
• 1997

Daily rainfalls and evaporations from copper pan measured in Suweon from 1964 to 1996 were figured respectively so that past soil moisture deficits can be understood clearly at a glance in relation to the characteristics of weather. Past drought intensities in Suweon were computed on the basis of Oh's 50mm pan model estimating drought in terms of daily, monthly shortage of evapotranspiration and growthless time fraction. Yearly differences in drought seem to result mainly from yearly differences in rainfall distribution and intensity, because there is the periodical similarity in evaporation from year to year. The most intense drought continued from December, 1964 to June, 1965 for 190 days and the most frequent rainfalls were observed from June, 1989 to August, 1990 for 15 months. The applied Oh's drought estimation model was reinforced with figuring programs with a view to later application for other districts. Present economic value index of irrigation were distributed in the range of 120% to 210% of one season yield for spring chinese cabbage, calculated on the basis of 10 year's accumulation of its expectable future yield increase. Therefore, the same value can be invested for the installation of new irrigation system even only for spring chinese cabbage, if its depreciation period is 10 years.

• Journal of Information Processing Systems
• /
• v.13 no.5
• /
• pp.1243-1258
• /
• 2017

A new medical materials scheduling system and its modeling method for the complex rescue are presented. Different from other similar system, first both the BeiDou Satellite Communication System (BSCS) and the Special Fiber-optic Communication Network (SFCN) are used to collect the rescue requirements and the location information of disaster areas. Then all these messages will be displayed in a special medical software terminal. After that the bipartite graph models are utilized to compute the optimal scheduling of medical materials. Finally, all these results will be transmitted back by the BSCS and the SFCN again to implement a fast guidance of medical rescue. The sole drug scheduling issue, the multiple drugs scheduling issue, and the backup-scheme selection issue are all utilized: the Kuhn-Munkres algorithm is used to realize the optimal matching of sole drug scheduling issue, the spectral clustering-based method is employed to calculate the optimal distribution of multiple drugs scheduling issue, and the similarity metric of neighboring matrix is utilized to realize the estimation of backup-scheme selection issue of medical materials. Many simulation analysis experiments and applications have proved the correctness of proposed technique and system.

• The Journal of the Acoustical Society of Korea
• /
• v.38 no.5
• /
• pp.593-600
• /
• 2019

The similarity in tones between speakers can lower the performance of speaker verification. To improve the performance of speaker verification systems, we propose a multi-task learning technique using deep neural network to learn speaker information and age information. Multi-task learning can improve generalization performances, because it helps deep neural networks to prevent hidden layers from overfitting into one task. However, we found in experiments that learning of age information does not work well in the process of learning the deep neural network. In order to improve the learning, we propose a method to dynamically change the objective function weights of speaker identification and age estimation in the learning process. Results show the equal error rate based on RSR2015 evaluation data set, 6.91 % for the speaker verification system without using age information, 6.77 % using age information only, and 4.73 % using age information when weight change technique was applied.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.24 no.6
• /
• pp.513-524
• /
• 2022

Recently, detecting damages of civil infrastructures from digital images using deep learning technology became a very popular research topic. In order to adapt those methodologies to the field, it is essential to explain robustness of deep learning models. Our research points out that the existing pixel-based deep learning model evaluation metrics are not sufficient for detecting cracks since cracks have linear appearance, and proposes a new evaluation methodology to explain crack segmentation deep learning model more rationally. Specifically, we design, implement and validate a methodology to generate tolerance buffer alongside skeletonized ground truth data and prediction results to consider overall similarity of topology of the ground truth and the prediction rather than pixel-wise accuracy. We could overcome over-estimation or under-estimation problem of crack segmentation model evaluation through using our methodology, and we expect that our methodology can explain crack segmentation deep learning models better.

• Journal of KIISE
• /
• v.43 no.10
• /
• pp.1085-1093
• /
• 2016

Community-based Question Answering system is a system which provides answers for each question from the documents uploaded on web communities. In order to enhance the capacity of question analysis, former methods have developed specific rules suitable for a target region or have applied machine learning to partial processes. However, these methods incur an excessive cost for expanding fields or lead to cases in which system is overfitted for a specific field. This paper proposes a multiple machine learning method which automates the overall process by adapting appropriate machine learning in each procedure for efficient processing of community-based Question Answering system. This system can be divided into question analysis part and answer selection part. The question analysis part consists of the question focus extractor, which analyzes the focused phrases in questions and uses conditional random fields, and the question type classifier, which classifies topics of questions and uses support vector machine. In the answer selection part, the we trains weights that are used by the similarity estimation models through an artificial neural network. Also these are a number of cases in which the results of morphological analysis are not reliable for the data uploaded on web communities. Therefore, we suggest a method that minimizes the impact of morphological analysis by using character features in the stage of question analysis. The proposed system outperforms the former system by showing a Mean Average Precision criteria of 0.765 and R-Precision criteria of 0.872.