• Journal of Korean Society of Environmental Engineers
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• v.22 no.2
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• pp.241-249
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• 2000

In this study, UV-catalyzed $H_2O_2$ oxidation and $H_2O_2$ oxidation to remove contaminants from photo processing chemicals were investigated at various conditions. Photo processing chemicals contains high concentrations of organic compounds and has very low biodegradability. Hydrogen peroxide is subjected to gradual decomposition as metastable substance. In the process, short-lived and highly reactive hydroxyl radicals are formed. The decomposition can be significantly accelerated by use of appropriate catalyst, such as ultraviolet radiation. The experiments were conducted in a UV-free reflecting reactor in batch and a high-pressure mercury lamp was used as UV source. Mixing, cooling and ventilation of the reactor were operated during experiments. In $UV/H_2O_2$ oxidation and $H_2O_2$ oxidation, the removal efficiencies of $COD_{Cr}$, TOC and chromaticity increased with the increase of $H_2O_2$ dosage and were higher in the controlled pH condition of 3 than in original pH condition of 8. In $UV/H_2O_2$ oxidation under the optimum condition of pH 8 and 1.3 stoichiometric $H_2O_2$ dosage, the removal efficiencies of $COD_{Cr}$, TOC and chromaticity were 47.5%, 75.0% and 91.5% respectively and $BOD/COD_{Cr}$ ratio was significantly increased from 0.04 to 0.21.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.31-40
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• 2017

This paper deals with the high precision of GPS measurement reduction and its implementation on near real-time and kinematic mode for those applications requiring centimeter-level precision of the estimated coordinates, even if target stations are a few hundred kilometers away from their references. We designed the system architecture, data streaming and processing scheme. Intensive investigation was performed to determine the characteristics of the GPS medium-range functional model, IGS infrastructure and some exemplary systems. The designed system consisted of streaming and processing units; the former automatically collects GPS data through Ntrip and IGS ultra-rapid products by FTP connection, whereas the latter handles the reduction of GPS observables on static and kinematic mode to a time series of the target stations' 3D coordinates. The data streaming unit was realized by a DOS batch file, perl script and BKG's BNC program, whereas the processing unit was implemented by definition of a process control file of BPE. To assess the functionality and precision of the positional solutions, an experiment was carried out against a network comprising seven GPS stations with baselines ranging from a few hundred up to a thousand kilometers. The results confirmed that the function of the whole system properly operated as designed, with a precision better than ${\pm}1cm$ in each of the positional component with 95% confidence level.

• The KIPS Transactions:PartB
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• v.14B no.5
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• pp.321-328
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• 2007

In this paper, we propose a fast and dynamic Region-of-Interest coding method using the adaptive code-block discrimination algorithm in JPEG2000 images which complements the implicit ROI coding method and the modified implicit ROI coding method. For reducing the time of discriminating the code block, the proposed method estimates the characteristics of the shape of ROI and makes the shape of boundaries, and classifies the patterns of each code block. The method improves the preferred processing and loss of wavelet coefficients of background within the ROI code blocks by adaptively classifying the code blocks with the percentage of content of the wavelet coefficients using the thresholds of ROI and background. Also, the priority control of wavelet coefficients of background within ROI code block supports the rapid ROI coding by processing in batch based on patterns unlike the existing methods that process with unit of wavelet coefficients. To show the usefulness of this method, we compared this to the existing methods. There is no difference in performance, but we confirmed very speedy in processing time.

• The Korean Journal of Mycology
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• v.47 no.4
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• pp.359-371
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• 2019

To optimize the expression and secretion of ferritin protein associated with ion storage in the mushroom, Pleurotus eryngii, a recombinant secretion vector, harboring the ferritin gene, was constructed using a pPEVPR1b vector under the control of the CaMV 35S promoter and signal sequence of pathogen related protein (PR1b). The ferritin gene was isolated from the T-Fer vector following digestion with EcoRI and HindIII. The gene was then introduced into the pPEVPR1b secretion vector, and it was then named pPEVPR1b-Fer. The recombinant vector was transferred into P. eryngii via Agrobacterium tumefaciens-mediated transformation. The transformants were selected on MCM medium supplemented with kanamycin and its expression was confirmed by SDS-PAGE and western blotting. Expression of ferritin protein was optimized by modifying the culture conditions such as incubation time and temperature in batch and 20 L airlift type fermenter. The optimal conditions for ferritin production were achieved at 25℃ and after incubating for 8 days on MCM medium. The amount of ferritin protein was 2.4 mg/g mycelia, as measured by a quantitative protein assay. However, the signal sequence of PR1b (32 amino acids) seems to be correctly processed by peptidase and ferritin protein may be targeted in the apoplast region of mycelia, and it might not be secreted in the culture medium. The iron binding activity was confirmed by Perls' staining in a 7.5% non-denaturing gel, indicating that the multimeric ferritin (composed of 24 subunits) was formed in P. eryngii mycelia. Mycelium powder containing ferritin was tested as a feed additive in broilers. The addition of ferritin powder stimulated the growth of young broilers and improved their feed efficiency and production index.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.7
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• pp.1205-1212
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• 2000

The effect of temperature on the sources of organic acids and sludge when phosphorus was biologically released was evaluated in this study. The sludge used in this study was obtained from sequencing batch reactor processing the swine wastewater. Temperature is one of the most important parameters influencing the phosphorus release. As a result, the rate of phosphorus released was increased as the temperatures were increased from 5 to $30^{\circ}C$ regardless of the sources of organic acids used. Under anaerobic conditions, as acetate, propionate, glucose, and domestic wastewater were used as the sources of organic acids, the corresponding activation energy($E_a$) values were 49.83, 55.82, 54.61, and 45.44 KJ/mol, respectively. Temperature coefficient($\theta$) values were 1.0676, 1.0826, 1.0748, and 1.0698, respectively. Therefore, the rate of phosphorus released was increased as temperature was increased, whereas, the effect, of the sources of organic acids and temperature on the activation energy and temperature coefficient values were minimal. When the sludge previously adapted to acetate as external organic source was used, the activation energy and temperature coefficient values were 44.94 KJ/mol and 1.0570 respectively. The effect of temperature was minimal. These values obtained from the sludge previously adapted to acetate were smaller than those from the sludge not previously adapted to the same organic acid. This suggest that the sludge previously adapted to acetate was less dependent on temperature than that not adapted to the acetate.

• Journal of Korea Spatial Information System Society
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• v.8 no.2 s.17
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• pp.91-107
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• 2006

To handling the extreme situation that must manage positional information of a very large volume, at least millions of moving objects. A cluster-based sealable distributed computing system architecture, called the GALIS which consists of multiple data processors, each dedicated to keeping records relevant to a different geographical zone and a different time zone, was proposed. In this paper, we proposed a valid time management and time-zone shifting scheme, which are essential in realizing the long-term location data subsystem of GALIS, but missed in our previous prototype development. We explain how to manage valid time of moving objects to avoid ambiguity of location information. We also describe time-zone shifting algorithm with three variations, such as Real Time-Time Zone Shifting, Batch-Time Zone Shifting, Table Partitioned Batch-Time Zone Shifting, Through experiments related with query processing time and CPU utilization, we show the efficiency of the proposed time-zone shifting schemes.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.877-883
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• 2003

Multi-degradable master hatch (M/B) was prepared and 0.05 mm polyethylene (PP) food packaging films containing 0, 10, and 20% M/B were manufactured by inflation film processing. The films were exposed to UV radiation, fungi, and heat in order to observe their photolysis, biodegradability, and thermal degradability, respectively. While pure PP film maintained more than 70% of its original elongation after 8 weeks of UV radiation, an almost perfect loss in the elongation of PP film containing 20% M/B was observed. Significant decreases in elongation of PP films by heat treatment $(68{\pm}2^{\circ}C)$ were also found in samples containing the multi-degradable M/B. By observing changes in film surface after the inoculation of fungi using scanning electron microscopy (SEM), the biodegradability of plastic film could be accelerated with the addition of multi-degradable M/B. The results of the mulching test in yard showed that adding multi-degradable M/B can effectively degrade plastic films in natural environmental conditions without interrupting the growth of plants.

• Journal of Astronomy and Space Sciences
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• v.26 no.2
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• pp.229-236
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• 2009

KOorea Multi-purpose SATellite(KOMPSAT)-5 will be launched at 550km altitude in 2010. Accurate satellite position(20 cm) and velocity(0.03 cm/s) are required to treat highly precise Synthetic Aperture Radar(SAR) image processing. Ionosphere delay was eliminated using dual frequency GPS data and double differenced GPS measurement removed common clock errors of both GPS satellites and receiver. SAC-C carrier phase data with 0.1 Hz sampling rate was used to achieve precise orbit determination(POD) with ETRI GNSS Precise Orbit Determination(EGPOD) software, which was developed by ETRI. Dynamic model approach was used and satellite's position, velocity, and the coefficients of solar radiation pressure and drag were adjusted once per arc using Batch Least Square Estimator(BLSE) filter. Empirical accelerations for sinusoidal radial, along-track, and cross track terms were also estimated once per revolution for unmodeled dynamics. Additionally piece-wise constant acceleration for cross-track direction was estimated once per arc. The performance of POD was validated by comparing with JPL's Precise Orbit Ephemeris(POE).

• Economic and Environmental Geology
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• v.37 no.6 s.169
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• pp.603-612
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• 2004

Pyrochlore is known as one of the most promising materials for the immobilization of radionuclide in high level waste. This study included the synthesis, phase relation and characteristics of $pyrochlore(CaCeZr_xTi_{2-x}O_{7,\;x=0.2\~2.0)$ in the system of Ca-Ce-Zr-Ti-O. Using the CPS(Cold pressing and sintering) method, the mixtures of $CaCO3_,\;CeO_2,\;ZrO_2\;and\;TiO_2$ oxides were pressed, and sintered at $1100\~1600^{\circ}C$ for 20 hours. The optimal synthetic conditions at various compositions were differed from 1300 to $1600^{\circ}C$ Even in the optimal temperatures, pyrochlore or fluorite coexisted with minor amount of perovskite, $CeO_2\;or\;Ce_{0.75}Zr_{0.25}O_2$. It was confirmed that pyrochlore and fluorite structures were stable at $x\leq0.6\;and\;x\geq1.0$, respectively. Especially, the compositions of pyrochlore or fluorite showed non-stoichiometric compositions in that contents of Ca and Ti were more deficient and those of Zr and Ce were more excess than batch compositions with the increase of x value. These characteristics stemmed from the behavior of elements occupied at eight- and six-coordinated site, and then caused the coexistence of perovskite, $CeO_2\;or\;Ce_{0.75}Zr_{0.25}O_2$ along with pyrochlore or fluorite.

• Knowledge Management Research
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• v.22 no.4
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• pp.27-40
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• 2021

Click-Through Rate (CTR) prediction is a key function that determines the ranking of candidate items in the recommendation system and recommends high-ranking items to reduce customer information overload and achieve profit maximization through sales promotion. The fields of natural language processing and image classification are achieving remarkable growth through the use of deep neural networks. Recently, a transformer model based on an attention mechanism, differentiated from the mainstream models in the fields of natural language processing and image classification, has been proposed to achieve state-of-the-art in this field. In this study, we present a method for improving the performance of a transformer model for CTR prediction. In order to analyze the effect of discrete and categorical CTR data characteristics different from natural language and image data on performance, experiments on embedding regularization and transformer normalization are performed. According to the experimental results, it was confirmed that the prediction performance of the transformer was significantly improved when the L2 generalization was applied in the embedding process for CTR data input processing and when batch normalization was applied instead of layer normalization, which is the default regularization method, to the transformer model.