• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.2 s.302
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• pp.101-112
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• 2005

As we perceive the world as 3-dimensional through our two eyes, we can extract 3-dimensional information from stereo images obtained from two or more cameras. Since stereo images have a large amount of data, with recent advances in digital video coding technology, efficient compression algorithms have been developed for stereo images. In order to compress stereo images and to obtain 3-D information such as depth, we find disparity vectors by using disparity estimation algorithm generally utilizing pixel differences between stereo pairs. However, it is not unusual to have stereo images having different intensity values for several reasons, such as incorrect control of the iris of each camera, disagreement of the foci of two cameras, orientation, position, and different characteristics of CCD (charge-coupled device) cameras, and so on. The intensity differences of stereo pairs often cause undesirable problems such as incorrect disparity vectors and consequent low coding efficiency. By compensating intensity differences between left and right images, we can obtain higher coding efficiency and hopefully reduce the perceptual burden of brain to combine different information incoming from two eyes. We propose several methods of intensity compensation such as local intensity compensation, global intensity compensation, and hierarchical intensity compensation as very simple and efficient preprocessing tool. Experimental results show that the proposed algerian provides significant improvement in coding efficiency.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.2 s.302
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• pp.27-36
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• 2005

This thesis proposed an effective encryption method for the DCT-based image/video contents and made it possible to operate in a high speed by implementing it as an optimized hardware. By considering the increase in the amount of the calculation in the image/video compression, reconstruction and encryption, an partial encryption was performed, in which only the important information (DC and DPCM coefficients) were selected as the data to be encrypted. As the result, the encryption cost decreased when all the original image was encrypted. As the encryption algorithm one of the multi-mode AES, DES, or SEED can be used. The proposed encryption method was implemented in software to be experimented with TM-5 for about 1,000 test images. From the result, it was verified that to induce the original image from the encrypted one is not possible. At that situation, the decrease in compression ratio was only $1.6\%$. The hardware encryption system implemented in Verilog-HDL was synthesized to find the gate-level circuit in the SynopsysTM design compiler with the Hynix $0.25{\mu}m$ CMOS Phantom-cell library. Timing simulation was performed by Verilog-XL from CadenceTM, which resulted in the stable operation in the frequency above 100MHz. Accordingly, the proposed encryption method and the implemented hardware are expected to be effectively used as a good solution for the end-to-end security which is considered as one of the important problems.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.45 no.2
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• pp.81-89
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• 2008

Wideband speech, characterized by a bandwidth of about 7 kHz (50-7000 Hz), provides a substantial quality improvement in terms of naturalness and intelligibility. Although higher data rates are required, it has extended its application to audio and video conferencing, high-quality multimedia communications in mobile links or packet-switched transmissions, and digital AM broadcasting. In this paper, we present a new bandwidth-scalable coder for wideband speech and audio signals. The proposed coder spits 8kHz signal bandwidth into two narrow bands, and different coding schemes are applied to each band. The lower-band signal is coded using the ITU-T G.729/G.729E coder, and the higher-band signal is compressed using a new algorithm based on the gammatone filter bank with an invertible auditory model. Due to the split-band architecture and completely independent coding schemes for each band, the output speech of the decoder can be selected to be a narrowband or wideband according to the channel condition. Subjective tests showed that, for wideband speech and audio signals, the proposed coder at 14.2/18 kbit/s produces superior quality to ITU-T 24 kbit/s G.722.1 with the shorter algorithmic delay.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.45 no.2
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• pp.21-28
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• 2008

This paper proposes a novel reduced-reference assessment method for video quality assessment, in which one-dimensional (1-D) histograms of motion vectors (MVs) are used as features of videos. The proposed method is more efficient than the conventional methods in view of computation time, because the proposed quality metric decodes MVs directly from video stream in the parsing process instead of reconstructing the distorted video at the receiver. Moreover, in view of data size, the propose method is efficient because a sender transmits 1-D histograms of MVs accumulated over whole input video sequences. Here, we use 1-D histograms of MVs accumulated over the whole video sequences, which is different from the conventional methods that assessed each image independently. For testing the similarity between histograms, we use histogram intersection and histogram difference methods. We compare the proposed method with the conventional methods for 52 video clips, which are coded under varying bit rate, image size, and frame rate. Experimental results show that the proposed method is more efficient than the conventional methods and that the proposed method is more similar to the mean opinion score (MOS) than conventional algorithms.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.3
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• pp.889-896
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• 2015

Matrix metalloproteinase-2 (MMP2) is an endopeptidase, mainly responsible for degradation of extracellular matrix components, which plays an important role in cancer disease. A single nucleotide polymorphism (SNP) at -1306 disrupts a Sp1-type promoter site. The results from the published studies on the association between MMP2 -1306 C>T polymorphism and cancer risk are contradictory and inconclusive. In the present study, a meta-analysis was therefore performed to evaluate the strength of any association between the MMP2 -1306 C>T polymorphism and risk of cancer. We searched all eligible studies published on association between MMP2 -1306 C>T polymorphism and cancer risk in PubMed (Medline), EMBASE and Google Scholar online web databases until December 2013. Genotype distribution data were collected to calculate the pooled odds ratios (ORs) and 95% confidence intervals (95%CIs) to examine the strength of the association. A total of 8,590 cancer cases and 9,601 controls were included from twenty nine eligible case control studies. Overall pooled analysis suggested significantly reduced risk associated with heterozygous genotype (CT vs CC: OR=0.758, 95%CI=0.637 to 0.902, p=0.002) and dominant model (TT+CT vs CC: OR=0.816, 95%CI=0.678 to 0.982, p=0.032) genetic models. However, allelic (T vs C: OR=0.882, 95%CI=0.738 to 1.055, p=0.169), homozygous (TT vs CC: OR=1.185, 95%CI=0.825 to 1.700, p=0.358) and recessive (TT vs CC+CT: OR=1.268, 95%CI=0.897 to 1.793, p=0.179) models did not show any risk. No evidence of publication bias was detected during the analysis. The results of present meta-analysis suggest that the MMP2 -1306 C>T polymorphism is significantly associated with reduced risk of cancer. However, further studies with consideration of different populations will be required to evaluate this relationship in more detail.

• Journal of Korean Clinical Nursing Research
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• v.18 no.2
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• pp.284-295
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• 2012

Purpose: This study was done to clarify effects of bispectral index monitoring sedative administration, compared to MOAA/S (Modified Observer's Assessment of Alertness and Sedation), on conscious sedation, physiological stability and recovery time for patients undergoing endoscopic submucosal dissection. Methods: Participants In this study were patients who underwent endoscopic submucosal dissection because of early gastric cancer. Participants were assigned randomly to an experimental group receiving sedatives based on bispectral index monitoring or to a control group with the MOAA/S instrument. Movements, belching, memory, pain, discomfort, physiological stability (MBP, PR, $SpO_2$), and recovery time were measured during the treatment and recovery. Data were analyzed using Spearman partial correlation coefficient analysis, Mixed model and Wilcoxon rank sum test to determine differences in the parameters. Results: There were no statistically significant differences between the two groups for conscious sedation(movement, belching, memory, pain, or discomfort), physiological stability and recovery time. Conclusion: The results of this study indicate that no differences were found between the two types of monitoring. Thus, use of a bispectral index monitor in clinical practice enabling medical staff to readily assess the conscious sedation of for these patients is expected to be increasingly used as an objective assessment tool for conscious sedation for patient safety.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1995.06b
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• pp.27-53
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• 1995

In plant pathology there is an increasing necessity for improved cytological techniques as basis for the localization of cellular substances within the dynamic fine structure of the host-(plant)-pathogen-interaction. Low temperature (LT) preparation techniques (shock freezing, freeze substitution, LT embedding) are now successfully applied in plant pathology. They are regarded as important tools to stabilize the dynamic plant-pathogen-interaction as it exists under physiological conditions. - The main advantage of LT techniques versus conventional chemical fixation is seen in the maintenance of the hydration shell of molecules and macromolecular structures. This results in an improved fine structural preservation and in a superior retention of the antigenicity of proteins. - A well defined ultrastructure of small, fungal organisms and large biological samples such as plant material and as well as the plant-pathogen (fungus) infection sites are presented. The mesophyll tissue of Arabidopsis thaliana is characterized by homogeneously structured cytoplasm closely attached to the cell wall. From analyses of the compatible interaction between Erysiphe graminis f. sp. hordei on barley (Hordeum vulgare), various steps in the infection sequence can be identified. Infection sites of powdery mildew on primary leaves of barley are analysed with regard to the fine structural preservation of the haustoria. The presentation s focussed on the ultrastructure of the extrahaustorial matrix and the extrahaustorial membrane. - The integration of improved cellular preservation with a molecular analysis of the infected host cell is achieved by the application of secondary probing techniques, i.e. immunocytochemistry. Recent data on the characterization of freeze substituted powdery mildew and urst infected plant tissue by immunogold methodology are described with special emphasis on the localization of THRGP-like (threonine-hydrxyproline-rich glycoprotein) epitopes. Infection sites of powdery mildew on barley, stem rust as well as leaf rust (Puccinia recondita) on primary leaves of wheat were probed with a polyclonal antiserum to maize THRGP. Cross-reactivity with the anti-THRGP antiserum was observed over the extrahaustorial matrix of the both compatible and incompatible plant-pathogen interactions. The highly localized accumulation of THRGP-like epitopes at the extrahaustorial host-pathogen interface suggests the involvement of structural, interfacial proteins during the infection of monocotyledonous plants by obligate, biotrophic fungi.

• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.230-236
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• 1998

We have screened total 32 herbal drugs to find the highest activity against human cariogenic enzyme, glucosyltransferase (GTase) from the extracts of Magnoliae bark. The extracts were separated into three phases, i. e. water, n-butanol and ethylacetate according to their solvent polarity. Among them, ethylacetate fraction had approximately more than 70% of total activities, and the active principle was further isolated by prep. HPLC following silicagel column chromatography to yield single compound as white powder. The chemical structure of the compound was finally elucidated to be 4,4'-dihydroxy-3,3'-dimethoxylignan from the spectral data of FAB-MS. $^1H-\;and\;^{13}C-NMR$ spectrometries. The compound was also shown to have relatively strong antibacterial activity against ten types of cariogenic oral bacteria and one kind of Actinomyces sp.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.5 s.305
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• pp.55-62
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• 2005

In this paper, we propose the face recognition system using HNMA(Hippocampal Neuron Modeling Algorithm) which can remodel the cerebral cortex and hippocampal neuron as a principle of a man's brain in engineering, then it can learn the feature-vector of the face images very fast and construct the optimized feature each image. The system is composed of two parts. One is feature-extraction and the other is teaming and recognition. In the feature extraction part, it can construct good-classified features applying PCA(Principal Component Analysis) and LDA(Linear Discriminants Analysis) in order. In the learning part, it cm table the features of the image data which are inputted according to the order of hippocampal neuron structure to reaction-pattern according to the adjustment of a good impression in the dentate gyrus region and remove the noise through the associate memory in the CA3 region. In the CA1 region receiving the information of the CA3, it can make long-term memory learned by neuron. Experiments confirm the each recognition rate, that are face changes, pose changes and low quality image. The experimental results show that we can compare a feature extraction and learning method proposed in this paper of any other methods, and we can confirm that the proposed method is superior to existing methods.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.5 s.305
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• pp.85-94
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• 2005

Display characterization, deriving the relationship between digital input values and the corresponding CIEXYZ tri-stimulus values, is important to reproduce the accurate color in color management system. The relationship can be estimated from the nine channel TRCs(tone response curves) and the result of this characterization method is better than that of using three channel TRCs. However, the inverse display characterization using nine channel TRCs cannot be directly inverted because the CIEXYZ values corresponding to each of RGB values are inseparable. Accordingly, inverse display characterization is usually implemented by the 3D-LUT (look-up table) method. Although the result of 3B-LUT is accurate, creating the 3D-LUT requires a lot of memory space and considerable amount of measurements. Therefore the inverse characterization method is proposed based on the modeling of channel-dependent values and nine channel inverse process based on the GOG(gain, offset gamma) model. The proposed method enhances the accuracy of display characterization and reduces the complexity and the number of measurements data required for accuracy in 3-D LUT.