• Journal of Microbiology and Biotechnology
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• v.19 no.2
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• pp.136-139
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• 2009

Avermectin and its analogs are major commercial antiparasitic agents in the fields of animal health, agriculture, and human infections. Previously, comparative transcriptome analysis between the low-producer S. avermitilis ATCC31267 and the high-producer S. avermitilis ATCC31780 using a S. avermitilis whole genome chip revealed that 50 genes were overexpressed at least two-fold higher in S. avermitilis ATCC31780. To verify the biological significance of some of the transcriptomics-guided targets, five putative regulatory genes were individually cloned under the strong-and-constitutive promoter of the Streptomyces expression vector pSE34, followed by the transformation into the low-producer S. avermitilis ATCC31267. Among the putative genes tested, three regulatory genes including SAV213, SAV3818, and SAV4023 exhibited stimulatory effects on avermectin production in S. avermitilis ATCC31267. Moreover, overexpression of SAV3818 also stimulated actinorhodin production in both S. coelicolor M145 and S. lividans TK21, implying that the SAV3818, a putative TetR-family transcriptional regulator, could be a global upregulator acting in antibiotic production in Streptomyces species.

• The Journal of Fisheries Business Administration
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• v.50 no.1
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• pp.17-37
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• 2019

The purpose of this study is to estimate the resource recovery effect and the economic effect of the fishermen by the fisheries vessel buy-back program. First, this study standardizes the fishing efforts of coastal gill net, coastal trap, and coastal composite fisheries using Gavaris general linear model. Second, the resource evaluation is performed by using vessel buy-back program data, and also the CYP model based on exponential growth function is applied. In order to derive the effect of the vessel buy-back program, the MSY with the vessel buy-back program is compared with the MSY without the vessel buy-back program. Finally, we compare and analyze producer surplus under the equilibrium of the MEY and the OA using bioeconomic model. In conclusion, the vessel buy-back program has shown an increase in resource growth and economic improvement for the remaining fishermen. The result shows that the remaining fishermen are able to obtain an increase in producer surplus of about 53% due to the vessel buy-back program under equilibrium levels of the open access and the maximum economic yield.

• Asia pacific journal of information systems
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• v.31 no.3
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• pp.358-377
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• 2021

Knowledge drives business innovation. However, even if companies have the same knowledge element in the business ecosystem, innovation performance varies depending on the structural position of the technical knowledge network. This study investigated whether there is a difference in exploitative innovation according to the structural position of the AI technical knowledge network. We collected patents from the top 100 digital companies registered with the US Patent Office from 2015 to 2019 and classified the companies into knowledge producer-based brokers, knowledge absorber-based brokers, knowledge absorbers, and knowledge producers from the perspective of knowledge creation and flow. The analysis results are as follows. First, a few of the top 100 digital companies disseminate, absorb, and mediate knowledge, while the majority do not. Second, exploitative innovation is the largest, in the order of knowledge producer, knowledge absorber-based broker, knowledge absorber, and knowledge producer-based broker. Finally, patents for industrial intelligence occupy a large proportion, and knowledge producers are leading exploitative innovation. Therefore, latecomers need to expand their resources and capabilities by citing patents owned by leading companies and converge with existing industries into AI-based industries.

• Journal of Convergence for Information Technology
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• v.12 no.5
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• pp.92-99
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• 2022

This study show the empirical results and the models that explain the content creator's personal brand value in the user-generated content platform. Producer's brand value performance could have enhancement and dilution by their activities for the long-term and repetitive change. Therefore, for the measure and analysis, the models have to catch the effect from producer's the diverse activities. This study would find the guideline by competitive analysis between (1) the impact of in-group user's self-motivated participation and (2) the impact of the social links from the outside platform. Based on the analysis results, producer's creation activity as focused on the specific and professional category increase their brand value for the long-term. However, producers would have to upload diverse category, after users are bored to their similar videos' as before. These empirical results would be a guidelines to the content management strategies for producers and the platform.

• Environmental and Resource Economics Review
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• v.25 no.4
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• pp.517-543
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• 2016

This study aims to analyze economic impacts for changes in the oil cost of the anchovy boat seine fisheries in South Korea. As analytical approach, this study employs the exponential surplus production model to estimate the maximum sustainable yield and also utilizes the bioeconomic model to calculate changes in producer surplus of the anchovy boat seine fisheries under the open access responding to changes in the oil cost. As the result of analysis, increases in the oil cost due to prohibition of duty-free oil supply result in the negative impacts to the producer surplus of the anchovy boat seine fisheries in South Korea. However, increases in the oil cost of the anchovy boat seine fisheries lead voluntary exit to fishermen which can no more run their business. As a result, this study shows that fishing efforts of the anchovy boat seine fisheries reduce under the fishing efforts of the maximum sustainable yield ($F_{MSY}$) and stock of the anchovy increases.

• Ocean and Polar Research
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• v.39 no.3
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• pp.221-232
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• 2017

The purpose of this study is to estimate the extent of fisheries resource rebuilding and other economic effects on coastal gill-net fishery as a result of the Korean vessel buy-back program using with-without analysis based on methods estimating sustainable yields for all species caught by coastal gill-net fishery. Based on the results of with-without analysis, maximum sustainable yields (MSY) of all species caught by coastal gill-net fishery have been increased by the Korean vessel buy-back program. In addition, profits per vessel of maximum economic yield (MEY) of the species have been improved by the program. Further, yields and a producer surplus per vessel under an equilibrium of open access (OA) have increased because of the program. In detail, first of all, at the MSY level, the vessel buy-back program has led to about 21% fisheries resource recovery, and at the MEY level, it has led to about a 19% resource recovery. Secondly, at the MEY level and the OA level, the producer surplus per vessel has been increased by about 24% and 22% respectively by the vessel buy-back program.

• BMB Reports
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• v.29 no.3
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• pp.183-191
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• 1996

DNA fragments, homologous to the dTDP-D-glucose 4,6-dehydratase gene, obtained from the genomic DNA of Streptomyces antibioticus $T\ddot{u}99$, a producer of the unusual macrolide antibiotic chlorothricin, were cloned and sequenced. This dehydratase gene was designated as oxil. The coding region of the oxil gene is composed of 987 bp, and analysis of the DNA sequence data reveals sequences for the gene products of 329 amino acids (molecular weight of 36,037). The deduced amino acids are 59% identical to the StrE, dTDP-D-glucose 4,6-dehydratase from the streptomycin pathway. The oxil's function was examined by expressing it in E. coli using the T7 RNA polymerase/promoter system (pRSET) to produce an active fusion protein including a his tag. This enzyme shows specificity of substrate, specific only to dTDP-D-glucose.

• Industrial Engineering and Management Systems
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• v.8 no.3
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• pp.162-170
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• 2009

This paper deals with a closed-loop remanufacturing system with one manufacturer and one remanufacturer. The manufacturer sells new products bearing the 'Extended Producer Responsibility (EPR).' It is assumed that the manufacturer's collection rate of used products depends only on the buy-back cost, while that of the remanufacturer depends on the minimum allowed quality level of used products in addition to the buy-back cost. Through the development of mathematical models with the objective function of maximizing profit, we study an efficient operation policy of each party. The decision variables are the unit selling price of new products and remanufactured products, the unit buy-back cost of the used products of the manufacturer and remanufacturer, and the minimum allowed quality level. The validity of the model is examined through numerical examples and sensitivity analysis.

• Journal of Korean Society for Quality Management
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• v.18 no.1
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• pp.116-128
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• 1990

Consumer's demand level for products and goods selection power is considerably improved. The pressure of loss compensation is also being accelerated by products which bring damage on property. The producer prevents the loss from causing poor products and considering the quality cost allotment in these circumstances. That is to say, producer should be concerned with the strategy of product liability prevention instead of passive defence policy. This paper intends to estabilish the optimum quality cost in considering product liability, and present the correlation of quality cost elements and multiple regression analysis. It can utilized in qualitycost and budget planning.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.118-118
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• 2005