• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.4
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• pp.128-135
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• 2005

This study was done to improve the effectiveness of nitrification and denitrification using the aeration-anoxic combination method using CFSTR(continuous-flow stirred-tank reactor) attached with an anoxic reactor filled with a media. In order to calculate the concentration of nitric acid within the aeration tank proportional to the anoxic rate within the reactor, supernatant within the inflow and precipitation tanks were influxed into the anoxic reactor. The rate of nitrogen removal was calculated using the concentration of inflow and flow of returned supernatant. From the results of this experiment, the carbon source needed in the anoxic reactor came from the inflow so that anoxification was achieved completely using the inflow source without the introduction of an external carbon source. However, as the ratio of nitric acid becomes large in inflow and nitric acid flow, the carbon source within the input source decreases so that the concentration of carbon source is important.

• The Plant Pathology Journal
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• v.32 no.2
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• pp.136-144
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• 2016

Pseudomonas fluorescens pc78 is an effective biocontrol agent for soil-borne fungal diseases. We previously constructed a P43-gfp tagged biocontrol bacteria P. fluorescens pc78-48 to investigate bacterial traits in natural ecosystem and the environmental risk of genetically modified biocontrol bacteria in tomato rhizosphere. Fluctuation of culturable bacteria profile, microbial community structure, and potential horizontal gene transfer was investigated over time after the bacteria treatment to the tomato rhizosphere. Tagged gene transfer to other organisms such as tomato plants and bacteria cultured on various media was examined by polymerase chain reaction, using gene specific primers. Transfer of chromosomally integrated P43-gfp from pc78 to other organisms was not apparent. Population and colony types of culturable bacteria were not significantly affected by the introduction of P. fluorescens pc78 or pc78-48 into tomato rhizosphere. Additionally, terminal restriction fragment length polymorphism profiles were investigated to estimate the influence on the microbial community structure in tomato rhizosphere between non-treated and pc78-48-treated samples. Interestingly, rhizosphere soil treated with strain pc78-48 exhibited a significantly different bacterial community structure compared to that of non-treated rhizosphere soil. Our results suggest that biocontrol bacteria treatment influences microbial community in tomato rhizosphere, while the chromosomally modified biocontrol bacteria may not pose any specific environmental risk in terms of gene transfer.

• Magazine of the Korean Society of Agricultural Engineers
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• v.9 no.2
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• pp.1301-1305
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• 1967

Ground water flow can be studied with model test. Model test of ground water works are necessary for economic and safe design of the works. Also influence of the ground water flow to the durability and safety of hydraulic structures can be studied with this model. a. Sand model ; Water flow through porous media is the principle of sand model. Darcy's formula is the basic equation, $q=k{\frac{dh}{ds}}^{\circ}. The effect of the ground water flow on the grain system itself is represented with this model only. b. Hele-Shaw model ; In this model use is made of the viscous flow analogy. Viscous fluid such as glycerine flowing through two parallel plates depends on Poiseuille law, $q=-c{\frac{dh}{ds}}$. The analogue can be used vertically and horizontally. c. Heat model ; This is based on the analogy of the Fourier's law for heat conduction and Darcy's law for ground water flow. Especially unsteady problem can be studied with this model. A difficulty of the construction of this model is the isolation, which has to prevent losses of the heat. d. Electirc model ; Ohm's law for electric current is analogous to Darcy's law. Resistance material such as metal foil, graphite block, water with salt added, gelatine with salt added, ete. is connected to electric sources and resistor, and equi-voltage line is detected with galvanometer, $N_aCl$, $CuSo_4$, etc. are used as salt in the model. e. Membrane model ; This model is based on the facts that the deflection of a thin membrane obeys Laplace's equation if there is no load in the direction perpendicular to the membrane, and if the dellection is small.

• Korean Journal of Materials Research
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• v.27 no.3
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• pp.137-143
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• 2017

Boron-doped diamond (BDD) electrode has an extremely wide potential window in aqueous and non-aqueous electrolytes, very low and stable background current and high resistance to surface fouling due to weak adsorption. These features endow the BDD electrode with potentially wide electrochemical applications, in such areas as wastewater treatment, electrosynthesis and electrochemical sensors. In this study, the characteristics of the BDD electrode were examined by scanning electron microscopy (SEM) and evaluated by accelerated life test. The effects of manufacturing conditions on the BDD electrode were determined and remedies for negative effects were noted in order to improve the electrode lifetime in wastewater treatment. The lifetime of the BDD electrode was influenced by manufacturing conditions, such as surface roughness, seeding method and rate of introduction of gases into the reaction chamber. The results of this study showed that BDD electrodes manufactured using sanding media of different sizes resulted in the most effective electrode lifetime when the particle size of alumina used was from $75{\sim}106{\mu}m$ (#150). Ultrasonic treatment was found to be more effective than polishing treatment in the test of seeding processes. In addition to this, BDD electrodes manufactured by introducing gases at different rates resulted in the most effective electrode lifetime when the introduced gas had a composition of hydrogen gas 94.5 vol.% carbon source gas 1.6 vol.% and boron source gas 3.9 vol.%.

• Archives of design research
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• v.16 no.1
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• pp.219-228
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• 2003

Nowadays, the progress of high technology in modern society provides humankind with the opportunity to obtain diverse information easily and quickly. Among those rapidly progressing fields of high technology, digital media field has the ability to substitute for the multimedia information society by being applied to many related fields and daily life. Specifically, the concern and enthusiasm for the restoration of cultural property has risen. So, effective methods are required to decide on the preservation, restoration and academic value of cultural property. Among these, image processing technology using computers has been introduced. The restoration of cultural property using this technique has been studied vigorously in many advanced countries because this would allow us to restore damaged parts without destroying the original asset. However, in Korea, though we have numerous examples of cultural property with recorded history, research related to the items has scarcely been conducted. Accordingly, this study focuses on the investigation of virtual reality and the techniques applicable to restoring cultural property in addition to suggesting the significance and possibility of digitally restoring cultural property following the introduction of applicable examples both domestically and abroad.

• Korean Journal of Digital Imaging in Medicine
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• v.15 no.1
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• pp.39-45
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• 2013

PACS Import external image of the thread of the tasks and duties of hospital revenue and business efficiency falls over time. 500 beds or more medical imaging import work outside of the hospital, most hospitals use a PC, KIOSK, and was used in 15 hospitals where, CD Autoloader where use was the only one. Working hours compared to CD and DVD media to test the results of the Import target PC, KIOSK, CD Autoloader Import spent less time in the order, and also the greater capacity of CD Autoloader four times the PC, KIOSK 2 times Import could be implemented quickly. In addition, the waiting time of the patients was measured using the PC's time to Import, 2011 14.5 minutes and the average patient waiting time, KIOSK and later use CD Autoloader 2012 average patient wait time of 8.25 minutes, 43% of the existing average waiting time was 5.25 minutes to reduce. However, KIOSK case of a patient in a way that directly Import latency time was soon. Import of three ways: in terms of efficiency and excellent CD Autoloader way, the patient waiting time in terms of ease of use and KIOSK was excellent. In addition, with the introduction of CD Autoloader with KIOSK Joint of the items waiting time of patients and patient satisfaction rating is considered to be a major contribution.

• Journal of Broadcast Engineering
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• v.15 no.2
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• pp.304-312
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• 2010

This paper presents the design of alert message and message segmentation method for the Terrestrial DMB Automatic Emergency Alert Service Standard. This paper begins with the introduction of the standard and some background. The alert message contains the essential information of the alert. Structured information is represented as coded fields and the unstructured as short sentences. Design factors of each field are analyzed first. Next each field’s semantics and syntax are described. The message segmentation method is presented next. The previous study selected FIDC as the message delivery channel. However, in most cases, the size of the alert message exceeds the maximum size of FIG, which is the basic unit packet for the channel. The current T-DMB standard does not support the segmentation method for FIDC. To solve the problem, this paper proposes an elegant segmentation method that garantees reliable, flexible, and fast receiver characteristic. This paper concludes with some additional tasks that should be resolved before the full-time alert service.

• Journal of the Korea Society of Computer and Information
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• v.16 no.6
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• pp.99-109
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• 2011

Ubiquitous computing technology makes an impact on the appearance of u-learning and presents an advanced direction of futuristic school education. In ubiquitous learning environments, various embedded computational devices will be pervasive and interoperable across the network for supporting the learning, so users may utilize these devices anytime anywhere. An important next step for ubiquitous learning is the introduction of context-aware learning service that employing knowledge and reasoning to understand the local context and share this information in support of intelligent learning services. However, the existing studies on design and application of ontology context model to support context-aware service in actual school environments are incomplete state. This paper, therefore, suggests a scheme of constructing ubiquitous learning space for existing school network by introducing USN to support context-aware ubiquitous learning services. This paper, also, designs an ontology based context model for ubiquitous school environments which describes context information through OWL. To determine the suitability of proposed ubiquitous learning space and ontology context model, we implement some of context-aware learning services in the ubiquitous learning environments.

• Journal of Digital Convergence
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• v.12 no.5
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• pp.501-515
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• 2014

The enforcement of the digital switch been two years, but more than half of the viewers are still not enjoying the benefits of it. Therefore, the government proposed that 8VSB transmission method so that majority of the viewer is able to enjoy the benefits of a digital switch. However, the claim has been suggested that 8VSB transmission method will have negative impacts on broadcast market feedback. In this regard, this study verified the effect of 8VSB and the method of minimization on the broadcast market. This study has conducted in-depth interviews concerned experts to achieve this purpose. Results of an interview revealed that the negative impact on the market of content and platforms, network is very small. In other words, the majority of the experts argued that the policy of government about 8VSB transmission are inadequate and it is improved to broaden the choice of the broadcast consumer.

• Journal of Digital Convergence
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• v.14 no.12
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• pp.267-281
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• 2016

This study analyzed the contents of articles on GMO in Chosun Ilbo and Hankyoreh from 1994 through 2015 to check the trend of reporting on GMO as a science and technology risk issue. As a result, 'risk' and 'anxiety/concern' were continuously treated as important subjects, and there was a lack of depth and journalist's professionalism in all three periods: 'Introduction of GMO technology (1994-2000)', 'Development of GMO technology (2001-2010)' and 'Social acceptance of GMO (2011-2015).' In a comparison between the media with different ideological goals, the Chosun Ilbo had a stronger new-technological inclination to GMO than the Hankyoreh in reporting topics and tones of arguments. As a result of checking the relation of the tones in reporting with the 'risk-benefit' of GMO, reports in negative tones underlined 'risk' while those in positive tones, 'benefit.' This study could suggest improvements of subject bias and unprofessionalism in the domestic science journalism, the barometer of public awareness of disputes over science and technology risk.