• Journal of Broadcast Engineering
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• v.20 no.2
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• pp.204-214
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• 2015

Depth map upsampling is an approach to increase the spatial resolution of depth maps obtained from a depth camera. Depth map quality is closely related to 3D perception of stereoscopic image, multi-view image and holography. In general, the performance of upsampled depth map is evaluated by PSNR (Peak Signal to Noise Ratio). On the other hand, time-consuming 3D subjective tests requiring human subjects are carried out for examining the 3D perception as well as visual fatigue for 3D contents. Therefore, if an objective metric is closely correlated with a subjective test, the latter can be replaced by the objective metric. For this, this paper proposes a best metric by investigating the relationship between diverse objective metrics and 3D subjective tests. Diverse reference and no-reference metrics are adopted to evaluate the performance of upsampled depth maps. The subjective test is performed based on DSCQS test. From the utilization and analysis of three kinds of correlations, we validated that SSIM and Edge-PSNR can replace the subjective test.

• Korean Journal of Ecology and Environment
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• v.40 no.2
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• pp.327-336
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• 2007

This study assessed ecological health using a multi-metric fish model from 15 sites in the headwater watershed of southern Han River during June${\sim}$August 1999 and then compared the health with conventional community diversity index to figure out differences between health and diversity index. For the analysis, we adopted 10 metric IBI model for regional applications. During this survey, total number of species sampled were 24 (6 families) and varied depending on magnitude of ecological disturbance and stream order. In the mountainous streams, mean proportion of sensitive and insectivore species was composed of 91% and 56%, respectively, indicating a potential healthy conditions. However, tolerant species with 66% and omnivore species with 76% were sampled from the 2nd order stream, which was shown deterioration in the physical habitat quality. In the overall watershed, mean IBI value was 38, judging as "fair" condition by the health criteria. Values of Individual IBI were closely associated with stream order and this pattern was similar to other mountainous streams showing low chemical pollutions and disturbance. Our comparison between IBI and diversity index over the stream order showed a distinct difference; Shannon-Weaver diversity index overestimated the actual community conditions and the variation range in the 2nd order stream was greater in the diversity index. Overall data suggest that the multi-metric approach may to a useful tool for stream ecosystem management and the conventional diversity index may not effective unless the stream order is considered for the stream evaluation.

• Korean Journal of Ecology and Environment
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• v.41 no.2
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• pp.228-236
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• 2008

The purpose of this study was to evaluate fish metric attributes using a model of Lentic Ecosystem Health Assessment (LEHA) and apply the model to the dataset sampled from six sites of Namyang Reservoir during October 2005$\sim$May 2006. The model was composed of 11 metries and the metric attributes were made of physical, chemical and biological parameters. Trophic composition's metrics showed that tolerant species ($M_3$, 80%) and omnivore species ($M_4$, 92%) dominated the fish fauna, indicating a biological degradation in the aquatic ecosystem. The metric of $M_7$, relative proportions of exotic species, also showed greater than 8% of the total, indicating a ecological disturbance. The average value of LEHA model was 24.3 (n= 12) in the reservoir, indicating a "poor condition" by the criteria of An and Han (2007). Spatial variation based on the model values was low (range: $21{\sim}26$), and temporal variation occurred due to a monsoon rainfall. Electrical conductivity (EC) and tropic state index of chlorophyll-$\alpha$ [TSI(CHL)] was greater in the premonsoon than the postmonsoon.

• Journal of Broadcast Engineering
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• v.19 no.1
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• pp.31-43
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• 2014

A depth map is an important component for stereoscopic image generation. Since the depth map acquired from a depth camera has a low resolution, upsamling a low-resolution depth map to a high-resolution one has been studied past decades. Upsampling methods are evaluated by objective evaluation tools such as PSNR, Sharpness Degree, Blur Metric. As well, the subjective quality is compared using virtual views generated by DIBR (depth image based rendering). However, works on the analysis of the relation between depth map upsampling and stereoscopic images are relatively few. In this paper, we investigate the relationship between subjective evaluation of stereoscopic images and objective performance of upsampling methods using cross correlation and linear regression. Experimental results demonstrate that the correlation of edge PSNR and visual fatigue is the highest and the blur metric has lowest correlation. Further, from the linear regression, we found relative weights of objective measurements. Further we introduce a formulae that can estimate 3D performance of conventional or new upsampling methods.

• The Journal of the Korea Contents Association
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• v.9 no.7
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• pp.110-120
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• 2009

Recently raising the recognition and it joins in about software quality evaluation and authentication and the recognition is augmented in about importance of the high quality security which leads a quality investment from the software development enterprise. The quality investor do to become accomplished but substantially from which degree level, quality investment it leads and the verification of software quality improvement does not become accomplished substantially and with without being it does and wants the enterprises where are clear the quality improvement which leads a quality investment does not set the direction where the problem occurs. From the research which it sees international ISO/IEC 9126 where it is standard and in about software test ISO/IEC 12119 where it is a guide it constructed the metric in base and software tentative instance it led and is accumulated and the defect data which it analyzed. result escape it investigated/to analyze quality level and it analyzed is weak from development process part and a defect level and the quality rating instance of Middleware] software and escape a disposal plan it investigated. The research which it sees it leads and it induces it is quantitative/that there is a possibility of being sufficient it sees the quality increase of Middleware software and the demand which is qualitative.

• Journal of KIISE:Software and Applications
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• v.34 no.4
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• pp.342-358
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• 2007

Ubiquitous Computing System (UCS) is a system where the user can get information through computer network anytime and anywhere regardless of the places. Since UCS is a personalized system, it should interact with other systems. UCS will bring a remarkable change in production, consumption, politics, economy, community, culture, and other areas related to our daily life. That is, a high-quality UCS results in high-quality services provided to users. Hence, this paper proposes a systematic quality model based on ISO/lEC 9126 in order to evaluate the ubiquitous computing system, based on ISO/lEC 9126. And, we identify key characteristics of UCS and derive the set of quality attributes based on identified characteristics. We define metrics for each quality attribute and Ubiquitous Computing Quality Model CUCQM) so that we can evaluate overall environment and important characteristics of UCS.

• International Journal of Computer Science & Network Security
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• v.24 no.1
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• pp.163-177
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• 2024

The fingerprint image quality relies on the clearness of separated ridges by valleys and the uniformity of the separation. The condition of skin still dominate the overall quality of the fingerprint. However, the identification performance of such system is very sensitive to the quality of the captured fingerprint image. Fingerprint image quality analysis and enhancement are useful in improving the performance of fingerprint identification systems. A fuzzy technique is introduced in this paper for both fingerprint image quality analysis and enhancement. First, the quality analysis is performed by extracting four features from a fingerprint image which are the local clarity score (LCS), global clarity score (GCS), ridge_valley thickness ratio (RVTR), and the Global Contrast Factor (GCF). A fuzzy logic technique that uses Mamdani fuzzy rule model is designed. The fuzzy inference system is able to analyse and determinate the fingerprint image type (oily, dry or neutral) based on the extracted feature values and the fuzzy inference rules. The percentages of the test fuzzy inference system for each type is as follow: For dry fingerprint the percentage is 81.33, for oily the percentage is 54.75, and for neutral the percentage is 68.48. Secondly, a fuzzy morphology is applied to enhance the dry and oily fingerprint images. The fuzzy morphology method improves the quality of a fingerprint image, thus improving the performance of the fingerprint identification system significantly. All experimental work which was done for both quality analysis and image enhancement was done using the DB_ITS_2009 database which is a private database collected by the department of electrical engineering, institute of technology Sepuluh Nopember Surabaya, Indonesia. The performance evaluation was done using the Feature Similarity index (FSIM). Where the FSIM is an image quality assessment (IQA) metric, which uses computational models to measure the image quality consistently with subjective evaluations. The new proposed system outperformed the classical system by 900% for the dry fingerprint images and 14% for the oily fingerprint images.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.4
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• pp.379-384
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• 2010

The service quality is one of the most important issue for successful deployment of IPTV services. Currently, a number of parameters have been reported that they have an effect on the quality of IPTV services. However, it is almost impossible to monitor and manage all the parameters in real time. Key parameters, therefore, should be chosen as a service metric for efficient quality management of IPTV services. For this purpose, we implement an environment for monitoring and measuring the quality of IPTV services and try to figure out the effect of each parameter on the quality of IPTV services. In particular, we focus on a parameter called continuous count error (CCE) measured at the level of MPEG transport stream (TS) and show that it has a greater effect on the quality of IPTV services than other parameters.

• The KIPS Transactions:PartB
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• v.15B no.5
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• pp.383-390
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• 2008

Block based transform coding is most popular approach for image and video compression. However it suffers from severe quality degradation especially from blocking artifacts. The subjective quality degradation caused by such blocking artifacts in general does not agree well with an objecive quality measurement such as PSNR. Hence new quality evaluation technique is necessary. We propose a new image quality assessment method by measuring blocking artifacts for block based transform coded images. In order to characterize blocking artifacts, proposed method utilizes the facts that, blocking artifacts, when occur, have different pixel values along the block boundaries and such differences usually continuously span along the whole boundaries. This method does not require the original uncompressed image. It operates on single block boundary and quantifies the amount of blocking artifacts on it. Experiments on various compressed images various bitrates show that proposed quantitative measure of blocking artifacts matches well with the subjective quality of them judged by human visual system.

• Journal of Broadcast Engineering
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• v.14 no.4
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• pp.387-396
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• 2009

No-Reference video-quality assessments are divided into two kinds of metrics based on decoding pixel domain or the bitstream one. Traditional full-/reduced- reference methods have difficulty to be deployed as realtime video transmission because it has problems of additional data, complexity, and assessment accuracy. This paper presents simple and highly accurate no-reference video-quality assessment in realtime video transmission. Our proposed method uses quantization parameter, motion vector, and information of transmission error. To evaluate performance of the proposed algorithm, we perform subjective test of video quality with the ITU-T P.910 Absolute Category Rating(ACR) method and compare our proposed algorithm with the subjective quality assessment method. Experimental results show the proposed quality metric has a high correlation (85%) in terms of subjective quality assessment.