Search

Paldang Lake in the Han River system is an important source for supplying drinking water. Recently, the occurrence of odor compounds geosmin and 2-methylisoborneol (2-MIB), in Lake Paldang has adversely affected the drinking water supply. The causative organisms of odor compounds have not been identified. Thus, this study analyzed the correlation between odor compounds and microorganisms and identified the odor-producing microorganisms in the Han River system. Odor compounds were primarily detected in the Bukhan River system but not in the Namhan River system. Geosmin was detected at high concentrations in summer, whereas 2-MIB was detected at high concentrations in summer and autumn. Microorganisms that appeared at the time of geosmin occurrence were actinobacteria (0.317, p < 0.01) and Dolichospermum (0.326, p < 0.01) among cyanobacteria, and the correlation was significant. The occurrence of 2-MIB mainly coincided with actinobacteria (0.745, p < 0.01) and Pseudanabaena (0.321, p < 0.01) among cyanobacteria, and the correlation was significant. Therefore, to manage the odor compounds in Lake Paldang, which is a drinking water source, it is important to control the appearance of actinobacteria and cyanobacteria in the Bukhan River system.

As the only glycoside hydrolase family 48 member in Clostridium thermocellum, the exoglucanase Cel48S plays a crucial role in the extremely high activity of the cellulosome against crystalline cellulose. Although the importance of Cel48S in the hydrolysis of crystalline cellulose has been widely accepted, an efficient production system has not yet been established because Cel48S is usually expressed in Escherichia coli within inactive inclusion bodies. For unstable proteins like Cel48S, translocation across the inner membrane can be more advantageous than cytoplasmic production due to the presence of folding modulators in the periplasm and the absence of cytoplasmic proteases. In this study, we evaluated whether the production of Cel48S in the periplasmic space of E. coli could enhance its functional expression. To do so, we attached the PelB signal peptide, which mediates post-translational secretion, to the N-terminal end of Cel48S (P-Cel48S). The PelB signal peptide allowed catalytically active Cel48S to be successfully produced in the culture medium. In addition, we investigated the role of an alternative co-translational pathway on the extracellular production of Cel48S, finding that co-translational secretion yielded a specific activity of recombinant Cel48S of 135.1 ± 10.0 U/mg cell in the culture medium, which was 2.2 times higher than that associated with P-Cel48S expression. Therefore, we believe that our approach has potential applications for the cost-effective conversion of lignocellulosic biomass and the industrial production of other unstable proteins.

Caldicellulosiruptor bescii is the most thermophilic, cellulolytic bacterium known and has the native ability to utilize unpretreated plant biomass. Cellulase A (CelA) is the most abundant enzyme in the exoproteome of C. bescii and is primarily responsible for its cellulolytic ability. CelA contains a family 9 glycoside hydrolase and a family 48 glycoside hydrolase connected by linker regions and three carbohydrate-binding domains. A truncated version of the enzyme (TM1) containing only the endoglucanase domain is thermostable and actively degrades crystalline cellulose. A catalytically active TM1 was successfully produced via the attachment of the PelB signal peptide (P-TM1), which mediates post-translational secretion via the SecB-dependent translocation pathway. We sought to enhance the extracellular secretion of TM1 using an alternative pathway, the signal recognition particle (SRP)-dependent translocation pathway. The co-translational extracellular secretion of TM1 via the SRP pathway (D-TM1) resulted in a specific activity that was 4.9 times higher than that associated with P-TM1 overexpression. In batch fermentations, the recombinant Escherichia coli overexpressing D-TM1 produced 1.86 ± 0.06 U/ml of TM1 in the culture medium, showing a specific activity of 1.25 ± 0.05 U/mg cell, 2.7- and 3.7-fold higher than the corresponding values of the strain overexpressing P-TM1. We suggest that the TM1 secretion system developed in this study can be applied to enhance the capacity of E. coli as a microbial cell factory for the extracellular secretion of this as well as a variety proteins important for commercial production.

Purpose To quantify the structural and perfusion changes in choriocapillaris in chronic central serous chorioretinopathy after half-dose photodynamic therapy by using spectral-domain optical coherence tomography and optical coherence tomography angiography. Methods This retrospective interventional case series examined the eyes of patients with central serous chorioretinopathy. Patients underwent full ophthalmic examinations, including spectral-domain optical coherence tomography and angiography, prior to and 1, 3, and 6 months after the treatment. Clinical and tomographic features of the choriocapillaris and choroidal thickness and vascular changes were evaluated by assessing flow signal voids. Results All 56 eyes of 56 patients showed complete resolution of subretinal fluid at 3 months after photodynamic therapy. The best-corrected visual acuity significantly improved at 6 months (p

Bukholderia pyrrocinia CAB08106-4 has an anti-fungal effect on Garlic White Rot caused bySclereotium cepivorum and Sclereotium sp. It is environmentally friendly microbial product that prevents andcontrols a variety of phytopathogens including Garlic White Rot caused by Sclereotium cepivorum andSclereotium sp. The aim of this study was to assess the environmental toxicity using Cyprinus carpio andDaphnia magna. Bukholderia pyrrocinia CAB08106-4 (1.0× 10 9 cfu/mL) was adminatrated to Cyprinus carpioand Daphnia magna according to the toxicity test guideline for peciticide. LC 50 of Bukholderia pyrrociniaCAB08106-4 is over 6.67× 10 4 cfu/mL in Cyprinus carpio and Daphnia magna and no adverse effect wasobserved. Based on these results, we concluded that Bukholderia pyrrocinia CAB08106-4 has no toxiciy forCyprinus carpio and Daphnia magna.Key words Biopesticide, Bukholderia pyrrocinia CAB08106-4, Environmental evaluation, Garlic White rot 서론 세계 여러 나라에서 농작물의 보호를 위해 화학농약을 기초로 한 화학 방제 기법이 주가 되어왔다. 하지만 화학농약의 사용은 오남용에 따른 독성영향과 환경오염 뿐만 아니라약제의 내성종 출현 등의 악영향이 나타난다. 따라서 지속가능한 식량생산을 위해 독성이 낮고 친환경적인 농약의 필요성이 대두되었다(Mancebo et al., 2011). 이에 많은 연구자들이 자연친화적인 방제법을 개발하고 있다. 또한 최근의소비가 웰빙(well-being)의 형태로 변화하면서 소비자들이보다 안전한 먹거리를 구매하고 있다(Park, 2011).생물농약(Biopesticide)은 생물방제재 또는 청정농약으로일컬어지고 있으며, 자연계에 존재하는 천연물질과 생물체및 그로부터 유래한 소재를 이용하여 농작물에 발생하는 병,해충, 및 잡초를 방제하는 작물보호제이다. 생물농약에는 미생물농약(Microbial pesticide)과 생화학농약(Biochemicalbiopesticide) 등이 있는데 그중에서도 가장 많이 개발되고있는 것은 세균, 곰팡이, 바이러스, 선충 등으로 개발하는미생물농약이다. 2002년 현재 미국 EPA에는 76개의 미생물농약과 113개의 생화학농약이 등록되어 있으며, 유럽의 경우 미국과 그 정의가 조금 다르지만 British Crop ProtectionCouncil에서 출판한 “The Manual of Biocontrol Agents,4rd edition”에 따르면 미생물농약 112 품목이 등록되어 시판되고 있으며, 천연물농약은 58 품목이 등록되어 있고,Semichemicals, 즉 반 합성화합물 농약은 56 품목이 등록되

Background/Objectives: This study doesn’t introduce the process of manufacturing system in smart factory of company but conducts a study on smart manufacturing’s ultimate goal which is to systematically view and identify the success factors through production system introduction and utilization. Methods/Statistical Analysis: In this study, BSC model was chosen to measure the performance of the enterprise on smart factory and it was modified to fit the purpose of this study. Factors that influences smart factory introduction are user engagement, goal clarification, and capacity of development enterprises. Three specific factors that were found as ERP success factors were drawn from related prior studies. We found out if these influence factors leads to successful introduction and if it would bring positive impact by re-incorporating the study of structural practices and commenting and creating important variables. Findings: We want to empirically identify the results after introducing smart factory through BSC model. First, user participation, introduction motive cost factor, introduction motive relationship factor, development industry’s capacity were four independent variables and using all four at once, PLS analyze result shows all four factors had positive influence on smart factory enterprise introduction. Secondly, when we analyze four categorized factors, user participation, introduction motive relationship factor, development industry’s capacity were important factors to increase learning outcome and process factor. Improvements/Applications: This study’s result provides practical implication of main factors that must be managed to ensure successful introduction to companies who wish to introduce the smart factory.

Background/Objectives: The present study analyzes an improvement plan for bicycle roads by using the public data of Seoul and proposes its implications. Methods/Statistical Analysis: In this study, an analysis was performed by utilizing a big data analysis tool, R. The present study, after defining the deducted problem phenomenon, conducted a process of planning which included the necessary information for finding an alternative for resolution and a data and application analysis technique. The data needed in the analysis was obtained from the Seoul open data square and the public data portal. The study attempted analysis and visualization by using the open source tool of R for analyzing the data, and conducted a process of interpretation. Findings: In this study attempts to find an alternative that can prevent bicycle safety exercises. The study presents the problems of current bicycle roads and their improvement plan by big data analysis which includes the relationship between the installation rate of bicycle roads and the bicycle accident rate, the location of bicycle roads, the location of bicycle amenities, and population data. In this study attempts to find an alternative that can prevent bicycle safety exercises. To achieve this, the study presents the problems of current bicycle roads and their improvement plan by big data analysis which includes the relationship between the installation rate of bicycle roads and the bicycle accident rate, the location of bicycle roads, the location of bicycle amenities, bicycle satisfaction, bicycle use statistics, and population data. The generalization of bicycle roads to regular residences implies a construction by considering the connectivity and stability of bicycle roads, but atypical infrastructure construction has played a part in increased damages resulting from the ignorance of bicycle users to traffic safety regulations. The perception of bicycle users must change and the building of bicycle roads must be based on people centered transportation infrastructure. Application/Improvements: The results of this study can be used as part of improvement of bicycle road accidents by central government and local governments. The results seem to be applied in policy, such as building bike paths centered around pedestrians.

Background/Objectives: The purpose of this study is to recognize the significance of security of cloud service activation and success and to draw the direction and importance for the development of Korean cloud service. Cloud computing service makes it possible to conduct a test easily and quickly at a low cost, to be scalable with an inexpensive cost, and to curb unnecessary expenses.Methods/Statistical analysis: This study collected news articles from NAVER with the use of crawling technique. The collected data were pre-processed (cleaned), and then 25 words with a high priority were analyzed in the category of the first half of 2015, the second half of 2015, and the first half of 2016.Findings: To find the trend of cloud computing service security, this study collected news articles and analyzed them after data cleaning. The analysis revealed that there was a difference in importance of each period. In the first half of 2015, the 2nd half of 2015, and the 1st half of 2016, the common noun words extracted were cloud, service, security, and enterprise in order.The difference was that the word 'environment' was found in the 1st half of 2015, the word 'management' in the 2nd half of 2015, and the words 'customer' and 'use' in the 1st half of 2016.Improvements/Applications: According to the analysis, there was a difference in importance by year. It is considered that the study results will be able to serve as the guidelines for establishing a systematic plan of cloud service security in the firms and institutions providing cloud service.

The heating unit of direct heating method manufactured as the plasma spray coating of conductive heating material on the surface of heating unit in order to improve the disadvantages of indirect heating method. and NiCr (80wt.%Ni-20wt.%Cr) that had the properties of conduction and heating was chosen for the conductive heating material. The compositions of the composite powders were studied . As the heating temperature was increased, the hardness of heating layer was increased because of the fine microstructure and the decrease of porosity. The adhesion strength was decreased for coarsening and connection of voids in the insulation layer, and the electrical resistivity of heating layer was increased for fine crack formation and growth. In this study, the best efficient sprayed coatings with heating unit was concluded as the plasma sprayed coatings that was heat treated at .

As recognition and value on big data has become significant, companies, public institutions, intelligence agencies have started to have interest on big data. Of course, there were analytic techniques based on data in past as well, but data was limited and analysis also limited. However nowadays, interest on structured data due to social media and unstructured data has started to increase that interest on big data analysis is rising. This paper systematically analyzes behavior of internet shopping mall users through big data analysis and proposes a strategic operation plan using this analysis.

Methane combustion over Pd catalyst supported on KIT-1 mesoporous material was investigated. The catalytic activity of the Pd catalyst was considerably improved by titania loading. The stability of the Pd catalyst to the exposure at high temperature is also enhanced by titania loading. Titania which is chemically bonded with the skeletal of mesoporous material interacts with palladium co-loaded and suppresses the decomposition of palladium oxide; more active phase in the methane combustion compared to palladium metal, resulted in the improvement in the catalytic performance of the Pd catalyst.

We demonstrate an interference cancellation technique of optical AND gate receiver using optical thyristor for fiber-optic code division multiple access (FO-CDMA) systems. In particular, we fabricate the optical thyristor operating as optical hard-limiter and evaluate that the optical AND gate receiver using fabricated optical thyristor excludes the peaks of side-lobe and cross-correlation result in the system performance degradation. It found that the optical AND gate receiver using optical thyristor excludes the intensity of interference signal resulting in that the peaks of side-lobe and cross-correlation can be fully eliminated for any two users. Therefore, the optical AND gate receiver using optical thyristor is shown to be effective to accommodate more simultaneous users.