• Journal of Microbiology and Biotechnology
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• v.23 no.10
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• pp.1403-1412
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• 2013

Ethanol fuel production from lignocellulosic biomass is emerging as one of the most important technologies for sustainable development. To use this biomass, it is necessary to circumvent the physical and chemical barriers presented by the cohesive combination of the main biomass components, which hinders the hydrolysis of cellulose and hemicellulose into fermentable sugars. This study evaluated the hydrolytic capacity of enzymes produced by yeasts, isolated from the soils of the Brazilian Cerrado biome (savannah) and the Amazon region, on sugarcane bagasse pre-treated with $H_2SO_4$. Among the 103 and 214 yeast isolates from the Minas Gerais Cerrado and the Amazon regions, 18 (17.47%) and 11 (5.14%) isolates, respectively, were cellulase-producing. Cryptococcus laurentii was prevalent and produced significant ${\beta}$-glucosidase levels, which were higher than the endo- and exoglucanase activities. In natura sugarcane bagasse was pre-treated with 2% $H_2SO_4$ for 30 min at $150^{\circ}C$. Subsequently, the obtained fibrous residue was subjected to hydrolysis using the Cryptococcus laurentii yeast enzyme extract for 72 h. This enzyme extract promoted the conversion of approximately 32% of the cellulose, of which 2.4% was glucose, after the enzymatic hydrolysis reaction, suggesting that C. laurentii is a good ${\beta}$-glucosidase producer. The results presented in this study highlight the importance of isolating microbial strains that produce enzymes of biotechnological interest, given their extensive application in biofuel production.

• Microbiology and Biotechnology Letters
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• v.48 no.3
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• pp.237-251
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• 2020

Lactic acid bacteria prevent the contamination of food products by inhibiting proliferation of pathogenic bacteria. This is done mainly by the production of lactic acid and antimicrobial peptides (AMP_S) known as bacteriocins. The interest in these molecules resides in both their antimicrobial spectrum and safety for human health. The application of bacteriocins or producer strains has been considered to avoid the development of pathogenic bacteria, as most bacteriocins have significant inhibitory activity against food pathogens, such as Listeria monocytogenes. This article describes the classification, structure, mode of action, biosynthesis, and main applications of bacteriocins in different fields: agri-food, aquaculture, and medicine.

• Journal of Korea Multimedia Society
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• v.8 no.11
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• pp.1462-1471
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• 2005

Recently, the medical image has been digitized by the development of computer science and digitization of the medical devices. There are needs for database service of the medical image and long term storage because of the construction of PACS(picture archiving and communication system) following DICOM(digital imaging communications in medicine) standards, telemedicine, and et al. However, it also caused some kinds of problems, such as illegal reproduction of medical image, proprietary rights and data authentication. In this paper, we propose the new digital watermarking technique for medical image based on public key encryption algorithm for integrity verification. It prevents illegal forgery that can be caused after transmitting medical image data remotely. The watermark is the value of bit-plane in wavelet transform of the original image for certification method of integrity verification. We proposed the embedding regions are randomly chosen considering ROI, and a digital signature is made using hash function of MD5 which input is a secret key. The experimental results show that the watermark embedded by the proposed algorithm can survive successfully in image processing operations and that the watermark's invisibility is good.

• Journal of Korea Multimedia Society
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• v.3 no.5
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• pp.542-549
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• 2000

This Paper presents the development of multiresolution model for the analysis and visualization of two-dimensional flows over curvilinear grids. Multiresolution analysis provides a useful and efficient tool to represent shape and to analyze features at multiple level of detail. Applying multiresolution analysis to vector field visualization is very useful and powerful as the vector field's data sets are usually huge and complex. Using approximation at lower resolution, brief outline of topology can be extracted in short periods of time. Local reconstruction allows the user to zoom in or out, only by reconstructing the portion of interest. This new model is based upon nested spaces of piecewise defined function over nested curvilinear grid domains. The nested domains are selected so as to maintain the original geometry of the inner boundary. This paper presents the refinement and decomposition equations for Haar wavelet over these domains and shows some examples.

• Journal of Korea Multimedia Society
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• v.16 no.12
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• pp.1495-1507
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• 2013

Smart device appeared as IT technology develops and it caused the proliferation of digital contents. It is because that App technology supports to install and use the contents in the smart device easily. App is developed by the creativity and the programming skill and the commercial value is generated in the process of development. In this paper, we taught how to develop APP to elementary school students by Android App Inventor program and observed the changes of their thinking through reflection-note which describes thinking of them. This research was carried out for 28 elementary school students, 5th and 6th grade. We found the attitude that students try to solve problem actively with the high interest. They enjoy showing developed App to others easily and quickly, which is the characteristic of smart devices. We also found a phenomenon that the students consider commercial value.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.822-827
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• 2009

As research for URC robot to advance the robot system dissemination and pracical use becomes active, also interest for robot platform and standardization is increasing. However, URC robot middleware does not involve a convergence with IT. Although it seems to be a high connection between robots and IT, the existing middleware has not considered different environments, thus making convergence efforts difficult. The middleware should improve their functions in order to synchronize with IT and to interact through formatted messages. In this paper, we present the necessity of the formatted message in the development of URC platform. In addition, design of the message protocol for the convergence based on the analysis of RUPI, OPC and SECS-II.

• Journal of Korea Technology Innovation Society
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• v.18 no.1
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• pp.73-97
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• 2015

Various types of government R&D support are available for activating businesses by small and medium sized enterprises (SMEs). However, most existing studies on this topic are focused only on the financial aspect. Interest in non-financial R&D support from the government has recently grown due to the limited provision of government financial support. In this study, government R&D support for SMEs was categorized into financial and non-financial strategies. Performance in terms of technological innovation by type was also analyzed. Furthermore, as R&D performance could vary according to the characteristics of the firms, the study classified performance variables into technological development possibility, technology intensity and technology uniqueness. The relationship between the types of support and the characteristics of the performance was also examined. Based on the results, it was found that government R&D support positively influences the SMEs' technological performance. However, the level of financial support does not significantly influence the technological uniqueness. As such, it is expected that effects from the increase in quantity of government R&D support are limited.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.12
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• pp.2410-2416
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• 2016

Recently, most countries in the world have pursued a denuclearization. So it has been of interest to increase to Nuclear weapon in such as North Korea's continued nuclear test. Pulsed gamma rays produced in the nuclear explosion and the space environment can give the big damage to the electronic device in a very short period of time. To confirm the extent of damage of these electronic devices, pulsed gamma irradiation facility that can occur in nuclear weapon or space environment are required. In this paper, we implemented the pulsed gamma-ray detection module and analyzed output of the irradiation test. We have experimented using an electron beam accelerator research facilities in Pohang Accelerator similar conditions to equip and Nuclear weapon. As a result, we confirmed that the pulsed gamma rays emitted by the gamma radiation and electron beam conversion device. The results of this paper will contribute to improve the reliability and accuracy of studies for utilizing pulsed gamma rays.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.12
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• pp.2357-2364
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• 2017

Recently, smart wearable devices for monitoring health status have been utilized as interest in health care has increased. In this paper, we developed a fatigue measurement system that works with smart wearable devices. Unlike physical fatigue that is restored when you take enough rest, mental fatigue can decrease the efficiency or concentration of work, so you can monitor your mental health status through measurements. This system provides the function to transmit the measured data from the smart wearable device to the smartphone and to calculate the mental fatigue. A fatigue index was developed to measure fatigue and expressed as a number from 1 to 5. In addition, the results of the fatigue calculation and the survey were compared with the results of the independent sample t-test. Therefore, this system will be used to help users manage their health efficiently.

• KIEAE Journal
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• v.9 no.3
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• pp.13-20
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• 2009

Globally, the issue of aging populations has become a significant one, and while Korea is not yet in the same position as many other countries, it has been changing rapidly into an aged society. Korea will be an aged society and this will increase the problems which are associated with an aged society. So we are in the urgent situation of looking the solutions for aged society problems. On this theme, a society which is rapidly aging has a growing interest with developing solutions for suitable elderly housing. A possible model of elderly housing which accomplished this is shared housing. Shared housing is more integrated in local society, and is designed like a small-scale house concept. Also as it provides benefits for social, economical and practical to the continuance of independent life, the shared housing which gives the possibility of sustainable life in the local society is a unique housing type and not only an extension of a housing community, but also it an alternative plan of social integration. This study is one of the methods for the proposal of an alternative plan for the sustainable housing using a small group workshop. It aims to understand the housing preferences of seniors and introduce various shared housing types to a low-income senior group and offer new information of the shared housing for the future. So I give the source that senior could think about their housing plan and what is housing preference type. I anticipate that the better elderly environments, facilities and service to the elderly shared housing development in the future.