• Journal of Microbiology and Biotechnology
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• v.34 no.5
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• pp.1154-1163
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• 2024

Glucosylation is a well-known approach to improve the solubility, pharmacological, and biological properties of flavonoids, making flavonoid glucosides a target for large-scale biosynthesis. However, the low yield of products coupled with the requirement of expensive UDP-sugars limits the application of enzymatic systems for large-scale. C. glutamicum is a Gram-positive and generally regarded as safe (GRAS) bacteria frequently employed for the large-scale production of amino acids and biofuels. Due to the versatility of its cell factory system and its non-endotoxin producing properties, it has become an attractive system for the industrial-scale biosynthesis of alternate products. Here, we explored the cell factory of C. glutamicum for efficient glucosylation of flavonoids using apigenin as a model flavonoid, with the heterologous expression of a promiscuous glycosyltransferase, YdhE from Bacillus licheniformis and the endogenous overexpression of C. glutamicum genes galU1 encoding UDP-glucose pyrophosphorylase and pgm encoding phosphoglucomutase involved in the synthesis of UDP-glucose to create a C. glutamicum cell factory system capable of efficiently glucosylation apigenin with a high yield of glucosides production. Consequently, the production of various apigenin glucosides was controlled under different temperatures yielding almost 4.2 mM of APG1(apigenin-4'-O-β-glucoside) at 25℃, and 0.6 mM of APG2 (apigenin-7-O-β-glucoside), 1.7 mM of APG3 (apigenin-4',7-O-β-diglucoside) and 2.1 mM of APG4 (apigenin- 4',5-O-β-diglucoside) after 40 h of incubation with the supplementation of 5 mM of apigenin and 37℃. The cost-effective developed system could be used to modify a wide range of plant secondary metabolites with increased pharmacokinetic activities on a large scale without the use of expensive UDP-sugars.

• Computers and Concrete
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• v.5 no.2
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• pp.117-134
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• 2008

An experimental and numerical research was conducted to gain a deeper insight on the structural behaviour of deep-beams with indirect supports and to assess the size effects in the ultimate state behaviour. The experimental campaign focused on the influence of the reinforcement tie distribution height on the compression check of the support region and on the benefits of using unbonded prestressing steel. Three reduced scale specimens were tested and used to validate the results obtained with a nonlinear finite element model. As a good agreement could be found between the numerical and the experimental results, the numerical model was then further used to perform simulations in large scale deep-beams, with dimensions similar to the ones to be adopted in a practical case. Two sources of size effects were identified from the simulation results. Both sources are related to the concrete quasi-brittle behaviour and are responsible for increasing failure brittleness with increasing structural size. While in the laboratory models failure occurred both in the experimental tests as well as in the numerical simulations after reinforcement yielding, the numerically analysed large scale models exhibited shear failures with reinforcement still operating in the elastic range.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1430-1432
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• 2003

Agricultural areas in the north region of Bangladesh suffer from water shortages during the dry season as well as dry spells in the monsoon period. The Teesta Barrage was constructed in 1990 to provide supplemental irrigation water during the monsoon period. After completion of the project high yielding variety of crops were introduced more in the project area. Due to this reason unforeseen needs of irrigation water during the dry season has emerged. This study reviews the current irrigation status and related constraints to a full development of the project and provides suggestions for future improvement of the project. Also suggested is to apply remote sensing technique for the management of the system as a whole. Use of remote sensing technique for the management of irrigation water resources is a new approach in Bangladesh. Application of such a powerful tool will provide better management options for large-scale irrigation projects in the country.

• Journal of Information Technology Services
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• v.4 no.1
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• pp.117-128
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• 2005

When we conduct development of a large-size SI project, it is highly necessary to utilize an appropriate application framework which helps to build a qualified software with high productivity in a short period of time. In this paper, we propose the architecture of a dynamically reconfigurable CBD application integration framework that has been used for developing large-scale e-business applications to achieve high development productivity and maintainability. This Integration framework can easily extend its functionalities, and dynamically change its configuration during run time according to the business category, such as applying interaction patterns among main components in software architecture, rules, policies, and environmental parameters. Dynamic reconfiguration has the feature to make applications be easily customized for changeable requirements. Through our application integration framework, huge sizes of contents can be managed according to the business category as well, by keeping configuration informations and huge volumes of source codes. In order to evaluate out application integration framework in terms of performance criteria, we present experimental results of throughputs from the framework by yielding dynamic configuration without any performance degradation.

• International Journal of Contents
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• v.16 no.3
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• pp.18-32
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• 2020

The aim of this study was to perform a meta-analysis of the learning outcomes of immersive learning technologies in English language teaching (ELT). This study examined 12 articles, yielding a total of 20 effect sizes. The Comprehensive Meta-Analysis (CMA) program was employed for data analysis. The findings revealed that the overall effect size was 0.84, implying a large effect size. Additionally, the mean effect sizes of the dependent variables revealed a large effect size for both the cognitive and affective domains. Furthermore, the study analyzed the impact of moderator variables such as sample scale, technology type, tool type, work type, program type, duration (sessions), the degree of immersion, instructional technique, and augmented reality (AR) type. Among the moderators, the degree of immersion was found to be statistically significant. In conclusion, the study results suggested that immersive learning technologies had a positive impact on learning in ELT.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.32 no.3
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• pp.252-255
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• 2019

Black phosphorus (BP) is a potential candidate for an anode in lithium ion batteries due to its high theoretical capacity and the large interlayer spacing in the monolayered phosphorene form, allowing for lithium intercalation/deintercalation. In this study, large-scale exfoliation of bulk BP was accomplished using a solution of NaOH and N-methyl-2-pyrrolidone (NMP), yielding phosphorene, which can be assembled into nanoflakes using electrophoretic deposition (EPD). Through the systematic addition of NaOH and subsequent sonication, BP nanoflakes were obtained in high yields by EPD, allowing for the integration of these nanoflakes into an anode in the film state. Anodes with a charge/discharge capacity of 172 mAh/g at a rate of 200 mA/g were obtained, which are promising for battery applications through various post-film treatments.

• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.4
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• pp.983-999
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• 2014

The structural design of the ships includes two main issues which should be checked carefully, namely the extreme structural response (yielding & buckling) and the fatigue structural response. Even if the corresponding failure modes are fundamentally different, the overall methodologies for their evaluation have many common points. Both issues require application of two main steps: deterministic calculations of hydro-structure interactions for given operating conditions on one side and the statistical post-processing in order to take into account the lifetime operational profile, on the other side. In the case of ultra large ships such as the container ships and in addition to the classical quasi-static type of structural responses the hydroelastic structural response becomes important. This is due to several reasons among which the following are the most important: the increase of the flexibility due to their large dimensions (Lpp close to 400 m) which leads to the lower structural natural frequencies, very large operational speed (> 20 knots) and large bow flare (increased slamming loads). The correct modeling of the hydroelastic ship structural response, and its inclusion into the overall design procedure, is significantly more complex than the evaluation of the quasi static structural response. The present paper gives an overview of the different tools and methods which are used in nowadays practice.

• Smart Structures and Systems
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• v.1 no.4
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• pp.385-404
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• 2005

The paper presents a model to calculate reinforcement strain using measured crack width in members under applied tension, flexure, and/or shear stress. Crack mapping using a new type of distributed coaxial cable sensors for health monitoring of large-scale civil engineering infrastructure was recently proposed and developed by the authors. This paper shows the results and performance of such sensors mounted on near surface of two flexural beams and a large scale reinforced concrete box girder that was subjected to cyclic combined shear and torsion. The main objectives of this health monitoring study was to correlate the sensor's response to strain in the member, and show that magnitude of the signal's reflection coefficient is related to increases in applied load, repeated cycles, cracking, and reinforcement yielding. The effect of multiple adjacent cracks, and signal loss was also investigated. The results shown in this paper are an important step in using the sensors for crack mapping and determining reinforcement strain for in-situ structures.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.9
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• pp.2223-2233
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• 1993

An engineering method is suggested to calculate the applied load versus crack extension in the elastic-plastic fracture. The condition for an increment of crack extension is set by a critical increment of crack-up opening displacement(CTOD). The ratio of the CTOD increment to the incremental crack extention is a critical crack-tip opening angle(CTOA), assumed to be constant for a material of a given thickness. The Dugdale model of crack-tip deformation in an infinite plate is applied to the method, and a complete solution for crack extension and crack instability is obtained. For finite-size specimens of arbitrary geometry in general yielding, an approximate generalization of the Dugdale model is suggested so that the approximation approaches the small-scale yielding solution in a low applied load and the finite-element solution in a large applied load. Maximum load is calculated so that an applied load attains either a limit load on an unbroken ligament or a peak load during crack extension. The proposed method was applied to three-point bend specimens of a carbon steel SM45C in various sizes. Reasonable agreements are found between calculated maximum loads and experimental failure loads. Therefore, the method can be a viable alternative to the J-R curve approach in the elastic-plastic fracture analysis.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.65-70
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• 2005

In this study, the large scale model tests were executed to estimate the Load Sharing Ratio(LSR) of raft in a piled footing under various conditions. The conditions such as the subsoil type, pile length, pile spacing, array type and pile installation method etc. were varied in the pile loading tests about the free-standing group piles and a piled footing. As the results of this study, it was found that there were no differences of the load-settlement curves, along with the pile installation method and subsoil type. The piles supported most of the external load until a yielding load of the piled footing, but the raft supported a considerable load after a yielding load. And it was also found that the LSR didn't be affected by the pile installation method and the subsoil type. As the relative density of sands increased, the LSR decreased. As the pile spacing was wider and the pile length increased, there was a tendancy for the LSR to increase.