• Journal of Electrical Engineering and Technology
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• v.9 no.2
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• pp.433-440
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• 2014

In this study, a method for the low-carbon active distribution system (ADS) planning is proposed. It takes into account the impacts of both network capacity and demand correlation to the renewable energy accommodation, and incorporates demand response (DR) as an available resource in the ADS planning. The problem is formulated as a mixed integer nonlinear programming model, whereby the optimal allocation of renewable energy sources and the design of DR contract (i.e. payment incentives and default penalties) are determined simultaneously, in order to achieve the minimization of total cost and $CO_2$ emissions subjected to the system constraints. The uncertainties that involved are also considered by using the scenario synthesis method with the improved Taguchi's orthogonal array testing for reducing information redundancy. A novel cuckoo search (CS) is applied for the planning optimization. The case study results confirm the effectiveness and superiority of the proposed method.

• Journal of Microbiology and Biotechnology
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• v.29 no.10
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• pp.1656-1664
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• 2019

Isoprene has the potential to replace some petroleum-based chemicals and can be produced through biological systems using renewable carbon sources. Ralstonia eutropha can produce value-added compounds, including intracellular polyhydroxyalkanoate (PHA) through fatty acid and lipid metabolism. In the present study, we engineered strains of R. eutropha H16 and examined the strains for isoprene production. We optimized codons of all the genes involved in isoprene synthesis by the mevalonate pathway and manipulated the promoter regions using pLac and pJ5 elements. Our results showed that isoprene productivity was higher using the J5 promoter ($1.9{\pm}0.24{\mu}g/l$) than when using the lac promoter ($1.5{\pm}0.2{\mu}g/l$). Additionally, the use of three J5 promoters was more efficient ($3.8{\pm}0.18{\mu}g/l$) for isoprene production than a one-promoter system, and could be scaled up to a 5-L batch-cultivation from a T-flask culture. Although the isoprene yield obtained in our study was insufficient to meet industrial demands, our study, for the first time, shows that R. eutropha can be modified for efficient isoprene production and lays the foundation for further optimization of the fermentation process.

• Food Engineering Progress
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• v.21 no.4
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• pp.383-390
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• 2017

Glucansucrase is an enzyme classified as a glycoside hydrolase (GH) 70 family, which catalyzes the synthesis of glucooligosaccharides with a low molecular weight using sucrose as a donor of D-glucopyranose and maltose as a carbohydrate acceptor. In this study, glucansucrase-producing lactic acid bacteria strain was isolated from the fermented foods collected in traditional markets, and the optimum conditions for the oligosaccharide production were investigated. The strain CCK940 isolated from Chinese cabbage kimchi was selected as an oligosaccharide-producing strain due to its high glucansucrase activity, with 918.2 mU/mL, and identified as Leuconostoc lactis. The optimum conditions for the production of oligosaccharides using Leu. lactis CCK940 were to adjust the initial pH to 6.0, add 5% (w/v) sucrose and 10% (w/v) maltose as a donor and acceptor molecules, respectively, and feed 5% (w/v) sucrose at 4 and 8 h of cultivation. When Leu. lactis CCK940 was cultured for 12 h at optimum conditions, at least four oligosaccharides with a polymerization degree of 2-4 were produced.

• Applied Chemistry for Engineering
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• v.22 no.1
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• pp.72-76
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• 2011

In this study, we investigated the characteristics of biodiesel using the waste coffee oil which was extracted by waste coffee grounds. We tried to deduce the optimum conditions by defining the operating variables, such as mole ratio between methanol and coffee oil (6~18) and the reaction temperature ($45{\sim}60^{\circ}C$) in the biodiesel production processes. The performance was evaluated in terms of yields, contents of fatty acid methyl ester (FAME), viscosities, and heating values. The optimum reaction temperature was $55^{\circ}C$. Also, the best biodiesel was produced at the mole ratio between methanol and coffee oil of 12. The highest heating value of the produced biodiesel made from coffee oil was 39.0~39.4 MJ/kg, which satisfies the general standard for the biodiesel energy density, 39.3~39.8 MJ/kg.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.6
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• pp.813-818
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• 2021

This paper proposes an optimized hardware implementation method for existing CIE1931 color gamut control algorithm. Among the post-processing methods of dehazing algorithms, existing algorithm with relatively low computations have the disadvantage of consuming many hardware resources by calculating large bits using Split multiplier in the computation process. The proposed algorithm achieves computational reduction and hardware miniaturization by reducing the predefined two matrix multiplication operations of the existing algorithm to one. And by optimizing the Split multiplier computation, it is implemented more efficient hardware to mount. The hardware was designed in the Verilog HDL language, and the results of logical synthesis using the Xilinx Vivado program were compared to verify real-time processing performance in 4K environments. Furthermore, this paper verifies the performance of the proposed hardware with mounting results on two FPGAs.

• International Journal of Computer Science & Network Security
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• v.21 no.7
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• pp.211-220
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• 2021

The aim of the study is to implement a factor analysis of the determinants of pricing in a state-regulated competitive market using economic and mathematical modelling methods and to develop ways to improve the pricing environment of the market under study. The purpose of the work defines the main objectives: (i) to investigate the features of the competitive model of the Ukrainian flour market; (ii) to analyse the current price conjuncture of the flour market and the dynamics of the main determinants of pricing; (iii)to develop ways of improving the price situation on the flour market on the basis of the factor analysis on the results of economic and mathematical modelling. In order to ensure the reliability and validity of the research results, the following methods were applied: the logical-dialectical method of scientific knowledge in the study of the main theoretical aspects of flour market functioning, the method of logical generalisation and synthesis, comparison, factor analysis, correlation and regression analysis, the graphical method, etc. It has been shown that pricing in a state-regulated competitive market has its own characteristics. For example, in the flour market the price of goods cannot be influenced by producers (sellers) by any methods, therefore determinants of pricing by indirect influence have been taken into account. The five-factor power model of wheat flour price has been constructed. It was substantiated that the price of wheat flour in Ukraine is mostly influenced by consumer price index (0.92 %). The received complex model of wheat flour price may be used also for medium-term forecasting and working out the ways of price formation optimization in the flour market.

• Journal of the Korea Society of Computer and Information
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• v.26 no.4
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• pp.47-53
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• 2021

In this paper, we propose a quadtree-based optimization technique that enables fast Super-resolution(SR) computation by efficiently classifying and dividing physics-based simulation data required to calculate SR. The proposed method reduces the time required for quadtree computation by downscaling the smoke simulation data used as input data. By binarizing the density of the smoke in this process, a quadtree is constructed while mitigating the problem of numerical loss of density in the downscaling process. The data used for training is the COCO 2017 Dataset, and the artificial neural network uses a VGG19-based network. In order to prevent data loss when passing through the convolutional layer, similar to the residual method, the output value of the previous layer is added and learned. In the case of smoke, the proposed method achieved a speed improvement of about 15 to 18 times compared to the previous approach.

• Journal of Powder Materials
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• v.29 no.1
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• pp.22-27
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• 2022

Conventionally, metal materials are produced by subtractive manufacturing followed by melting. However, there has been an increasing interest in additive manufacturing, especially metal 3D printing technology, which is relatively inexpensive because of the absence of complicated processing steps. In this study, we focus on the effect of varying powder size on the synthesis quality, and suggest optimum process conditions for the preparation of AlCrFeNi high-entropy alloy powder. The SEM image of the as-fabricated specimens show countless, fine, as-synthesized powders. Furthermore, we have examined the phase and microstructure before and after 3D printing, and found that there are no noticeable changes in the phase or microstructure. However, it was determined that the larger the powder size, the better the Vickers hardness of the material. This study sheds light on the optimization of process conditions in the metal 3D printing field.

• Advances in concrete construction
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• v.14 no.1
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• pp.1-13
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• 2022

Due to the physical-chemical characteristics of some bottom ash (BA), there are technical, economic and environmental limitations to find a destination that will add value to it. In Brazil, this residue is eventually used for filling coal extraction pits or remains in sedimentation ponds, creating a susceptible panorama to environmental issues. The geopolymers binders are one of the alternatives to the proper use high amounts of these materials. In this work, geopolymeric binder pastes were produced with BA mixed to activators with different alkali contents (expressed as %Na₂O), as well as the incorporation of soluble silicates (Ms content). The production of binary geopolymeric pastes based on the use of two industrial wastes: fluid catalytic cracking (FCC) and aluminum anodizing sludge (AAS), was also assessed. The content in mass of BA/FCC and BA/AAS ranged from 100/0, 90/10; 80/20 and 70/30. Systems with soluble silicates as activator in a molar ratio SiO₂/Na₂O of 1.0 (Ms = 1.0) and Na₂O content of 15%, showed the best results of mechanical strength (42 MPa at day 28^th). The improvement is up to 5X when compared to NaOH based systems. For systems with partial replacement of BA of 10% of AAS and 20% of FCC (80/20), the presence of soluble silicates was also effective to increase compressive strength.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.7 no.2
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• pp.85-91
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• 2021

Selective amino acid conjugation of bulky antibodies is a valuable asset for real-time diagnosis and therapy. However, selective conjugation incorporating a chelate-bearing radioactive atom into an antibody without affecting its immunoreactivity is a challenging task. A bifunctional chelator (BFC), a selective amino acid-targeting probe, and a linker have been developed to overcome this problem. Here, we report the synthesis of a novel propylene cross-bridged chelator (PCB)-1,8-N,N'-bis-(carboxymethyl)-1,4,8,11-tetraazacyclotetradecane (TE2A)-luminol BFC via a click reaction and radiolabel it with a ⁶⁴Cu ion for tyrosine-selective conjugation of trastuzumab. In the initial optimization study, we tried different oxidative addition conditions such as electro-oxidation, hemin, horseradish peroxidase, iodogen tube, chloramine-T, and iodo beads. In this study, up to 82% of ⁶⁴Cu-PCB-TE2A-luminol was conjugated with the antibody in an iodo bead-catalyzed oxidative addition reaction with an isolated yield of 24.4%.