• Journal of Broadcast Engineering
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• v.25 no.5
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• pp.665-671
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• 2020

MPEG-I is actively working on standardization on the coding of immersive video which provides up to 6 degree of freedom (6DoF) in terms of viewpoint. 3DoF+ video, which provides motion parallax to omnidirectional view of 360 video, renders a view at any desired viewpoint using multiple view videos acquisitioned in a limited 3D space covered with upper body motion at a fixed position. The MPEG-I visual group is developing a test model called TMIV (Test Model for Immersive Video) in the process of development of the standard for 3DoF+ video coding. In the TMIV, the redundancy between a set of input view videos is removed, and several atlases are generated by packing patches including the remaining texture and depth regions into frames as compact as possible, and coded. This paper presents an atlas generation method that removes small-sized blocks in the atlas for more efficient 3DoF+ video coding. The proposed method shows a performance improvement of BD-rate bit savings of 0.7% and 1.4%, respectively, in natural and graphic sequences compared to TMIV.

• Applied Microscopy
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• v.33 no.1
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• pp.1-16
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• 2003

As is well known that N-nitroso-N-methylurethane (NNNMU) causes acute lung injury (ALI) in experimental animals. And ALI caused by NNNMU is very similar to ARDS in human being in its pathology and progress. In its context, we investigated the pathogenetic mechanism of ARDS associated with oxidative stress by neutrophils in Sprague-Dawley rat model of NNNMU-induced ALI. NNNMU had increased lung weight/body weight ratio (L/B ratio), lung myeloperoxidase (MPO) activity, protein content and number of neutrophils in bronchoalveolar fluid (BALF) compared with those of control rat (p<0.001, respectively). In contrast, the amount of pulmonary surfactant in BALF was decreased by NNNMU (p<0.001). Morphologically, light microscopic examination denoted pathological findings such as formation of hyaline membrane, infiltration of neutrophils and perivascular cuffing in the lungs of NNNMU-treated rats. In addition, ultrastructural changes such as the necrosis of endothelial cells, swelling and vacuolization of lamellar bodies of alveolar type II cells, and the degeneration of pulmonary surfactant were identified after treatment of NNNMU. Very interestingly, cerium chloride electron microscopic cytochemistry showed that NNNMU had increased the production of cerrous-peroxide granules in the lung, which signified the increased production of hydrogen peroxide in the lung. Collectively, we conclude that NNNMU causes acute lung leak by the mechanism of neutrophilic oxidative stress of the lung.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.3
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• pp.384-388
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• 2002

Gamma irradiation was used to reduce the N-nitrosamines in emulsion-type cooked pork sausage during storage at 4$^{\circ}C$. The sausage without ascorbate to maximize the N-nitrosamine formation and the sausage with 200 ppm sodium ascorbate were prepared, respectively. The sausages were aerobically or vacuum packaged and irradiated at 0, 5, 10 and 20 kGy. A statistically significant difference was not shown in N-nitrosodimethylamine (NDMA) and N-nitrosopyrrelidine (NPYR) levels in the sausage prepared with sodium ascorbate at 0 week, while the NDMA and NPYR reduction was observed after 4 weeks storage. The NDMA level in the sausage without sodium ascorbate and irradiated at 10 kGy or above reduced in aerobic packaging, while a dose of 20 key was needed in vacuum packaging. The N-nitroscpyrrolidine reduction was shown at 20 and 30 kGy-irradiation. The results indicated that gamma irradiation was effective to reduce N-nitrosamines level in sausage during storage.

• Korean Journal of Microbiology
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• v.54 no.4
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• pp.384-397
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• 2018

The aim of this study is to screen the strains of Bacillus spp. possessing safety, probiotic activity, and so on, which can be utilized as probiotic resource for using the feed and supplement food of companion animal. About 300 isolates were isolated from traditional Korean sauces, four isolates that did not have or produce the six kinds of B. cereus type vomiting and diarrhea toxin genes, ${\beta}$-hemolytic, and three kinds of carcinogenic enzymes were selected. Antibiotic gene retention, cell surface hydrophobicity, antibiotic sensitivity, and glucose utilization were analyzed for four isolates, and finally SRCM 100731 was selected. SRCM 100731 was named as Bacillus amyloliquefaciens SRCM 100731 16S rRNA sequencing analysis, and carried out optimization of cell growth for industrial applications such as pet food and feed. The effects of 14 different components on cell growth were investigated and three significant positive factors, molasses, sodium chloride, and potassium chloride were selected as the main factors based on a Plackett-Burman design. In order to find out optimal concentration on each constituent, we carried out central composite design. The predicted optimized concentrations were 7% molasses, 1.1% sodium chloride, 0.5% potassium chloride. Finally, an overall about 7-fold increase in dry cell weight yield ($12.6625{\pm}0.0658g/L$) was achieved using the optimized medium compared with the non-optimized medium ($1.8273{\pm}0.0214g/L$). This research is expected to be highly utilized in the growing pet industry by establishing optimal cultivation conditions for industrial application as well as screening Bacillus amyloliquefaciens SRCM 100731 as probiotic resource for companion animal.

• Tuberculosis and Respiratory Diseases
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• v.42 no.2
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• pp.184-205
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• 1995

Background: Pulmonary toxicity by bleomycin has multiple mechanisms including direct tissue toxicity due to oxygen-derived free radicals and indirect toxicity through amplification of pulmonary inflammation. To evaluate the effect of chelators or free radical scavenger to lung damage induced by bleomycin, penicillamine as a copper chelator, deferoxamine as an iron chelator and vitamin E as a free radical scavenger were administered. Methods: Two hundred Wistar rats were divided into five groups: Control, bleomycin treated, bleomycin-penicillamine treated, bleomycin-deferoxamine treated, and bleomycin-vitamin E treated groups. Rats sacrificed on day 1, day 3, day 4, day 7, day 14, and day 28 after treatment. Bronchoalveolar lavage, light microscopic and immunohistologic studies for type I, III, IV collagens, fibronectin, laminin and NBD phallicidin were evaluated. Results: There was a significant increase in the total cell counts of bronchoalveolar lavage on day 1 from all treated animals and vitamin treated group showed an abrupt decrease in total cell counts with decrease of neutrophils on day 3. Bleomycin-vitamin E treated group had the least histologic changes such as pulmonary fibrosis. The alveolar basement membranes were positive for type IV collegen and laminin. Basement membranes of bleomycin, bleomycin-penicillamine, or bleomycin-deferoxamine treated groups were disrupted and fragmented on day 4 or 7. The bleomycin-vitamin E treated group had intact basement membranes until day 28. Conclusion: Bleomycin-induced pulmonary fibrosis was related to the severity of acute injury to oxygen radicals or activation of neutrophils and disruption of basement membrane. Vitamin E seemed to be the most effective antioxidant in the inhibition of bleomycin-induced pulmonary injury and fibrosis.

• Journal of KIISE:Software and Applications
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• v.36 no.9
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• pp.732-748
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• 2009

The technology of Semantic Web realizes the base technology for context-awareness that creates new services by dynamically and flexibly combining various resources (people, concepts, etc). According to the realization of ubiquitous computing technology, many researchers are currently working for the embodiment of web service. However, most studies of them bring about the only predefined results those are limited to the initial description by service designer. In this paper, we propose a new service supporting model to provide an automatic method for plan related tasks which achieve goal state from initial state. The inputs on an planner are intial and goal descriptions which are mapped to the current situation and to the user request respectively. The idea of the method is to infer context from world model by DL-based ontology reasoning using OWL domain ontology. The context guide services to be loaded into planner. Then, the planner searches and plans at least one service to satisfy the goal state from initial state. This is STRIPS-style backward planner, and combine OWL-S services based on AI planning theory that enabling reduced search scope of huge web-service space. Also, when feasible service do not find using pattern matching, we give user alternative services through DL-based semantic searching. The experimental result demonstrates a new possibility for realizing dynamic service modeler, compared to OWLS-XPlan, which has been known as an effective application for service composition.

• The KIPS Transactions:PartB
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• v.13B no.1 s.104
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• pp.53-62
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• 2006

Object recognition techniques using principal component analysis are disposed to be decreased recognition rate when lighting change of image happens. The purpose of this thesis is to propose an object recognition technique using new PCA analysis method that discriminates an object in database even in the case that the variation of illumination in training images exists. And the object recognition algorithm proposed here represents more enhanced recognition rate using improved k-Nearest Neighbor. In this thesis, we proposed an object recognition algorithm which creates object space by pre-processing and being learned image using histogram equalization and median filter. By spreading histogram of test image using histogram equalization, the effect to change of illumination is reduced. This method is stronger to change of illumination than basic PCA method and normalization, and almost removes effect of illumination, therefore almost maintains constant good recognition rate. And, it compares ingredient projected test image into object space with distance of representative value and recognizes after representative value of each object in model image is made. Each model images is used in recognition unit about some continual input image using improved k-Nearest Neighbor in this thesis because existing method have many errors about distance calculation.

• Journal of Science Education
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• v.41 no.2
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• pp.179-194
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• 2017

The purpose of this study is to construct two equivalent science relevance recognition test tool after confirming the reliability and validity of the CARS(Changes in Attitude of Relevance to Science) questionnaire to determine the applicability of the items to Korean students and to compare gender and school differences. For this study, 59 items of the CARS scientific relevance test were translated and assigned to 787 middle and high school students (analyed the answer of 300 middle school students and 431 high school students). In order to determine the fit of the CARS question to Korean students and to overcome the limitation of the number of questions, we used the item-linking method of the Rasch model. By analyzing the results of the research, we constructed two equivalent scientific relevance recognition questionnaires of CARS-A and CARS-B with 25 items. The Pearson correlation coefficient of the Rasch scores of the two equivalent test was 0.78. The two types of scientific relevance recognition test tools generated through this study can be used to confirm students' attitude of scientific relevance to daily life, or to confirm the change after a certain class or grade. Through this study, we will discuss the implications of students' perceptions of science associations in science education, and the development and application of tools.

• Journal of the Korea Computer Graphics Society
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• v.22 no.5
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• pp.17-26
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• 2016

This paper presents an adaptive slicing method based on merging vertical layer polylines. Firstly, we slice the input 3D polygon model uniformly with the minimum printable thickness, which results in bounding polylines of the cross section at each layer. Next, we group a set of layer polylines according to vertical connectivity. We then remove polylines in overdense area of each group. The number of layers to merge is determined by the layer thickness computed using the cusp height of the layer. A set of layer polylines are merged into a single polyline by removing the polylines within the layer thickness. The proposed method maintains the shape features as well as reduces the printing time. For evaluation, we sliced ten 3D polygon models using our method and a global adaptive slicing method and measured the total length of polylines which determines the printing time. The result showed that the total length from our method was shorter than the other method for all ten models, which meant that our method achieved less printing time.

• Geophysics and Geophysical Exploration
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• v.26 no.4
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• pp.171-184
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• 2023

Machine learning (ML)-based cavity detection using a large amount of survey data obtained from vehicle-mounted ground penetrating radar (GPR) has been actively studied to identify underground cavities. However, only simple image processing techniques have been used for preprocessing the ML input, and many conventional seismic and GPR data processing techniques, which have been used for decades, have not been fully exploited. In this study, based on the idea that a cavity can be identified using diffraction, we applied ML-based diffraction separation to GPR data to increase the accuracy of cavity detection using the YOLO v5 model. The original ML-based seismic diffraction separation technique was modified, and the separated diffraction image was used as the input to train the cavity detection model. The performance of the proposed method was verified using public GPR data released by the Seoul Metropolitan Government. Underground cavities and objects were more accurately detected using separated diffraction images. In the future, the proposed method can be useful in various fields in which GPR surveys are used.