• Journal of Microbiology and Biotechnology
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• v.24 no.1
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• pp.87-96
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• 2014

In the present study, a yeast species isolated from CETP, Vellore, Tamilnadu was identified as Cryptococcus sp. VITGBN2 based on molecular techniques and was found to be a potent producer of acidic diacetate sophorolipid in mineral salt media containing vegetable oil as additional carbon source. The chemical structure of the purified biosurfactant was identified as acidic diacetate sophorolipid through GC-MS analysis. This sophorolipid was used as a stabilizer for synthesis of zinc oxide nanoparticles (ZON). The formation of biofunctionalized ZON was characterized using UV-visible spectroscopy, XRD, scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy. The antimicrobial activities of naked ZON and sophorolipid functionalized ZON were tested based on the diameter of inhibition zone in agar well diffusion assay, microbial growth rate determination, protein leakage analysis, and lactate dehydrogenase assay. Bacterial pathogen Salmonella enterica and fungal pathogen Candida albicans showed more sensitivity to sophorolipid biofunctionalized ZON compared with naked ZON. Among the two pathogens, S. enterica showed higher sensitivity towards sophorolipid biofunctionalized ZON. SEM analysis showed that cell damage occurred through cell elongation in the case of S. enterica, whereas cell rupture was found to occur predominantly in the case of C. albicans. This is the first report on the dual role of yeast-mediated sophorolipid used as a biostabilizer for ZON synthesis as well as a novel functionalizing agent showing antimicrobial property.

• Journal of Advanced Navigation Technology
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• v.24 no.6
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• pp.601-606
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• 2020

In this paper, we designed a microstrip patch antenna that can be applied to the Wimax/LTE 5G system among wireless media usable in coastal ships. The substrate of the proposed antenna is FR-4 (er=4.3), the size is 22 mm × 30 mm, and it can be used in the 3.5 GHz and 5.8 GHz bands of Wimax/LTE 5G by constructing a simple structure using a microstrip patch antenna. CST Microwave Studio 2014 was used for simulation, and the gain of the simulation result is 2.41dB at 2.4 GHz and 3.96 dB at 3.5 GHz. S-Parameter also showed a result of less than -10 dB (VSWR 2:1) in the desired frequency band, and designed a small variable and a miniaturized antenna so that the antenna can be used in mobile phones or electronic devices.

• Convergence Security Journal
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• v.24 no.1
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• pp.43-49
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• 2024

The convergence of education and technology has been emphasized, leading to the application of educational technology (EdTech) in the field of education. EdTech provides learner-centered, customized learning environments through various media and learning situations. In this paper, we designed hardware for EdTech-based educational tools for IoT security education in the field of cybersecurity education. The hardware is based on a dual microcontroller unit (MCU) within a single board, allowing for both attack and defense to be performed. To leverage various sensors in the Internet of Things (IoT), the hardware is modularly designed. From an educational perspective, utilizing EdTech in cybersecurity education enhances engagement by incorporating tangible physical teaching aids. The proposed research suggests that the design of IoT security education hardware can serve as a reference for simplifying the creation of a security education environment for embedded hardware, software, sensor networks, and other areas that are challenging to address in traditional education..

• Journal of Mushroom
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• v.11 no.4
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• pp.194-200
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• 2013

Polyporus umbellatus (Syn. Grifola umbellata) is a sclerotium forming mushroom belongs to family Polyporaceae of Polyphorales, Basidiomycota. The sclerotia of P. umbellatus have long been used for traditional medicines in China, Korea and Japan. This study was initiated to obtain the basic data for artificial sclerotial production of P. umbellatus. Here, we investigated the favorable conditions for mycelial growth of P. umbellatus and its symbiotic fungus Armillaria mellea. We also evaluate the favorable carbon and nitrogen sources for sclerotial formation in dual culture between P. umbellatus and A. mellea. The favorable conditions for mycelial growth of P. umbellatus were $20^{\circ}C$ and pH 4, while optimal conditions for mycelial growth of A. mellea were $25^{\circ}C$ and pH 6. The carbon sources for optimal mycelial growth of P. umbellatus were fructose and glucose, while carbon sources for favorable mycelial growth of A. mellea were also fructose and glucose. The nitrogen sources for favorable mycelial growth P. umbellatus were peptone and yeast extract, while optimal mycelial growth of A. mellea were obtained in peptone and yeast extract. When P. umbellatus and A. mellea were dual cultured on carbon sources, sclerotia were induced on basal media supplemented with glucose, fructose and maltose at pH 4~6, while nitrogen sources inducing sclerotia were basal media supplemented with peptone and yeast extract for 60 days at $20^{\circ}C$ under dark condition.

• Journal of Broadcast Engineering
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• v.19 no.6
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• pp.896-906
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• 2014

In this paper, a real-time dual-mode temporal synchronization and compensation method based on a new reliability measure in stereoscopic video is proposed. The goal of temporal alignment is to detect the temporal asynchrony and recover synchronization of the two video streams. The accuracy of the temporal synchronization algorithm depends on the 3DTV contents. In order to compensate the temporal synchronization error, it is necessary to judge whether the result of the temporal synchronization is reliable or not. Based on our recently developed temporal synchronization method[1], we define a new reliability measure for the result of the temporal synchronization method. Furthermore, we developed a dual-mode temporal synchronization method, which uses a usual texture matching method and the temporal spatiogram method[1]. The new reliability measure is based on two distinctive features, a dynamic feature for scene change and a matching distinction feature. Various experimental results show the effectiveness of the proposed method. The proposed algorithms are evaluated and verified through an experimental system implemented for 3DTV.

• Journal of Broadcast Engineering
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• v.20 no.5
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• pp.697-705
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• 2015

This paper proposes a high-speed and high-quality haze removal method based on dual dark channels. In the conventional method, the halo artifacts are suppressed by the additional transmission refinement, but the transmission refinement is computationally intensive and the quality of the haze removal is sometimes unsatisfactory because of the residual halo artifacts. In the proposed method, the transmission is estimated with the mixture of the two dark channels with different window size. By mixing the two dark channels so as to avoid the halo artifacts, the proposed method realizes a high-quality haze removal even without the transmission refinement. Experimental results demonstrate that the quality of the results by the proposed method is superior to those by the conventional method and the speed of the haze removal is about 14.2 times higher than that of the conventional method.

• Journal of Korean Library and Information Science Society
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• v.8
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• pp.155-184
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• 1981

The publication of the result of scholarly research is an integral part of the process by which learning is advanced. The university presses, as one of the major scholarly publishers are now confronted with many critical problems, such as the declining unit sales, the explosion of manuscripts, the challenge of new publishing technologies, etc., in performing the role of the scholarly communication system. The purpose of this study is to identify the problems imposed on the university presses and alternative strategies for them. For the study, the related literature to the subject were read, analyzed and synthesized, from which the overall prospect of the problems and alternative strategies are derived. The conclusion of the study can be summarized as follows: (1) The faith of the university should lie in its role to advance scholarly learning through production and dissemination of high-quality knowledge, and the university press should materialize such a faith. (2) The scholarly books, though not the best media of scholarly communication taking a side view of its timeliness and brevity, can perform the function of the best media for the specific subject and readers. (3) The scholarly books as national resource must be published for the scholars demanding them even though the publication can't help depending on the subsidiary fund. (4) For the survival and activation of the university presses, the following strategies should be examined, and put in force if necessary. (a) The role of the foundation su n.0, pporting the university presses should be expanded (b) The Co-operative system among the operations of the presses should be established. (c) It is desirable that the university without the press should participate in the university with the press for both the financial su n.0, pporting and the publicizing its faculty's manuscripts. (d) The positive efforts should be made for the increase of sales copies by implementing the dual-system of publication. (e) It is desirable that 'recording system' should be incorporated in the traditional publication system both for the lightening of financial problems and the explosion of publications. (f) It is necessary that the effective methods of the bibliographical control should be developed for the improvement of the scholarly communication. (g) Any kind of the permanent organization composed of the representatives from all the infrastructures of information industry should be established to study the character and direction of technological changes and to discern the better choice of specific, technologies in the scholarly communication system.

• Journal of the Korean Society of Radiology
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• v.9 no.1
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• pp.9-16
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• 2015

The purpose of this study is finding optimum contrast medium quantity during abdominal CT using dual energy technique. The study subjects are 30 patients who had received general single energy abdominal CT and received double energy technique follow-up abdominal CT. dual energy technique abdominal CT images were obtained after setting contrast medium quantities at 30%, 40%, 50%, 60% and 70% of contrast medium quantity at the time of single energy technique. Then the contrast enhancement (Hounsfield Unit; HU) was estimated by setting-up the regions of interest at aorta, inferior vena cava, hepatic portal vein and hepatic parenchymal. The obtained values were compared to the values of the same parts measured during single energy technique abdominal CT. The results of the study were as following. The 60% set up group had HU in aorta : $210.80{\pm}13.609$, IVC : $190.40{\pm}25.215$, hepatic portal vein : $198.40{\pm}21.232$ and hepatic parenchymal : $119.20{\pm}7.98$, The single energy abdomianl CT images had HU in aorta : $205.40{\pm}16.426$, IVC : $188.20{\pm}21.476$, hepatic portal vein : $195.40{\pm}22.744$ and hepatic parenchymal : $121.00{\pm}6.595$. Therefore, it is possible to obtain contrast enhancement by dual energy technique abdominal CT similar to the same by single energy technique abdominal CT by setting-up the quantity of contrast medium at 60% of contrast medium at the time of single energy technique abdominal CT. Based on the result of this study, it is possible to decrease existing quantity of contrast medium by _% and the injection velocity can be also decreased. Accordingly, it is believed that the result of study would be quite useful for patients who have renal function disorder, weak vein or side effect of contrast medium in the past.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2010.07a
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• pp.150-151
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• 2010

본 논문에서는 잡음환경에서의 이중채널 음성인식을 위한 통계모델 기반 음성구간 검출 방법을 제안한다. 제안된 방법에서는 다채널 입력 신호로부터 얻어진 공간정보를 이용하여 음성 존재 및 부재 확률모델을 구하고 이를 통해 음성구간 검출을 행한다. 이때, 공간정보는 두 채널간의 상호 시간 차이와 상호 크기 차이로, 음성 존재 및 부재 확률은 가우시안 커널 밀도 기반의 확률모델로 표현된다. 그리고 음성구간은 각 시간 프레임 별 음성 존재 확률 대비 음성 부재 확률의 비를 추정하여 검출된다. 제안된 음성구간 검출 방법의 평가를 위해 검출된 구간만을 입력으로 하는 음성인식 성능을 측정한다. 실험결과, 제안된 공간정보를 이용하는 통계모델 기반의 음성구간 검출 방법이 주파수 에너지를 이용하는 통계모델 기반의 음성구간 검출 방법과 주파수 스펙트럼 밀도 기반 음성구간 검출 방법에 비해 각각 15.6%, 15.4%의 상대적 오인식률 개선을 보였다.

• Korean Journal Plant Pathology
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• v.14 no.3
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• pp.278-285
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• 1998

Effects of chitosan on growth of tomato plant, and suppression of Fusaruim wilt caused by Fusarium oxysporum f. sp. lycopersici and late blight casued by Phytophthora infestans, were examined. Both late blight and fusarium wilt were suppressed by spray and irrigation of chitosan, respectively. Inhibition of mycelial growth was not greatly affected by molecular size of chitosan but, concentration dependent effects was observed. Ninty percent of P. infestans and 80% of F. oxysporum f. sp. lycopersici of mycelial growth was inhibited by 1,000 ppm of chitosan (MW 30,000~50,000) when amended in plate media. Induction of defense-related gene expression in plant by chitosan treatments were observed when chitosan treated tobacco and tomato RNA samples were hybridized with several defense-related genes as probes. The results revealed that $\beta$-1,3-glucanase and chitinase genes were strongly induced, while pathogenesis-related protein-1, 3-hydroxy-3-methylglutaryl coenzyme A reductase, anionic peroxidase, phenylalanine ammonia lyase genes were weakly induced by chitosan treatment. These results suggest that chitosan have dual effects on these host-pathogen interactions. Possible roles of chitosan in suppression of tomato diseases by inhibition of mycelial growth and activation of plant defense responses are discussed.