• Geomechanics and Engineering
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• v.28 no.3
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• pp.265-281
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• 2022

A set of slurry shield test system capable of cutter cutting and slurry automatic circulation is used to investigate the deformation characteristics, the evolution characteristics of support resistance and the distribution and evolution process of earth pressure during excavating and collapsing of slurry shield tunneling in circular-gravel layer. The influence of cover-span ratio on surface subsidence, support resistance and failure mode of excavation face is also discussed. Three-dimensional numerical calculations are performed to verify the reliability of the test results. The results show that, with the decrease of the supporting force of the excavation face, the surface subsidence goes through four stages: insensitivity, slow growth, rapid growth and stability. The influence of shield excavation on the axial earth pressure of the front soil is greater than that of the vertical earth pressure. When the support resistance of the excavation face decreases to the critical value, the soil in front of the excavation face collapses. The shape of the collapse is similar to that of a bucket. The ultimate support resistance increase with the increase of the cover-span ratio, however, the angle between the bottom of the collapsed body and the direction of the tunnel excavation axis when the excavation face is damaged increase first and then becomes stable. The surface settlement value and the range of settlement trough decrease with the increase of cover-span ratio. The numerical results are basically consistent with the model test results.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1743-1748
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• 2014

A facile and effective method has been developed for the synthesis of a novel series of benzofuran derivatives via N-acylation, O-alkylation and intramolecular condensation reactions, starting from readily available substituted o-hydroxy aryl ketone, and chloroacetyl arylamides. This metal-free transition process is characterized by mild reaction conditions, atom economy, short reaction time and a high yield with a decreased amount of by-products.

• International Journal of Aeronautical and Space Sciences
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• v.14 no.3
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• pp.222-228
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• 2013

A jetfighter shape modeling method based on design features is researched, to improve the efficiency of shape modeling in the stage of conceptual aircraft design. The aircraft's general design features and shape parameters, including geometric and position parameters, are described. The coordinate systems of the entire aircraft and its components are defined. As a sample of local shape, a method of inlet intake modeling is introduced. The whole process of the modeling method is proposed. Three examples of different jetfighters are listed, to describe the achievement of basic layout, which includes four main elements. The Fusion of Components can be achieved by regulating the details of the sections of the fuselage. Sample Cases of typical layouts are shown to verify the effectiveness of the proposed method, which provides the basis for further analysis and optimization.

• International Journal of CAD/CAM
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• v.8 no.1
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• pp.63-67
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• 2009

This paper puts forward a method based on the boundary deformation for planar grid generation. Many methods start with the special properties of grid and switch to the solution of a direct optimization or a non-linear minimum cost flow. Though with high theoretical significance, it's hard to realize due to the extremely complicated computing process. This paper brings out the automatic generation of planar grid by studying the boundary deformational properties of planar grid, which leads to uniform grid and enjoys the simplicity of computation and realization.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.3
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• pp.51-61
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• 2012

This paper suggests an algorithm that obtains Directed Graph Minimum Spanning Tree (DMST), using Prim MST algorithm which is Minimum Spanning Tree (MST) of undirected graph. At first, I suggested the Prim DMST algorithm that chooses Minimum Weight Arc(MWA) from out-going nodes from each node, considering differences between undirected graph and directed graph. Next, I proved a disadvantage of Prim DMST algorithm and Chu-Liu/Edmonds DMST (typical representative DMST) of not being able to find DMST, applying them to 3 real graphs. Last, as an algorithm that can always find DMST, an advanced Prim DMST is suggested. The Prim DMST algorithm uses a method of choosing MWA among out-going arcs of each node. On the other hand, the advanced Prim DMST algorithm uses a method of choosing a coinciding arc from the out-going and in-going arcs of each node. And if there is no coinciding arc, it chooses MWA from the out-going arcs from each node. Applying the suggested algorithm to 17 different graphs, it succeeded in finding the same DMST as that found by Chu-Liu/Edmonds DMST algorithm. Also, it does not require such a complicated calculation as that of Chu-Liu/Edmonds DMST algorithm to delete the cycle, and it takes less time for process than Prim DMST algorithm.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.641-644
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• 2008

Traditional LTPS TFT needs additional LDD process to decrease leakage current. However the fabrication process is no suitable for PI substrate. Additional laser multi-irradiation will damage the poly-Si to cause the TFT electrical degrade. Therefore we propose the simplified process to activate the $N^+$ and $N^-$ at the same time.

• Journal of Microbiology and Biotechnology
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• v.28 no.11
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• pp.1850-1858
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• 2018

Glucosamine (GlcN) is widely used in the nutraceutical and pharmaceutical industries. Currently, GlcN is mainly produced by traditional multistep chemical synthesis and acid hydrolysis, which can cause severe environmental pollution, require a long prodution period but a lower yield. The aim of this work was to develop a whole-cell biocatalytic process for the environment-friendly synthesis of glucosamine (GlcN) from N-acetylglucosamine (GlcNAc). We constructed a recombinant Escherichia coli and Bacillus subtilis strains as efficient whole-cell biocatalysts via expression of diacetylchitobiose deacetylase ($Dac_{ph}$) from Pyrococcus furiosus. Although both strains were biocatalytically active, the performance of B. subtilis was better. To enhance GlcN production, optimal reaction conditions were found: B. subtilis whole-cell biocatalyst 18.6 g/l, temperature $40^{\circ}C$, pH 7.5, GlcNAc concentration 50 g/l and reaction time 3 h. Under the above conditions, the maximal titer of GlcN was 35.3 g/l, the molar conversion ratio was 86.8% in 3-L bioreactor. This paper shows an efficient biotransformation process for the biotechnological production of GlcN in B. subtilis that is more environmentally friendly than the traditional multistep chemical synthesis approach. The biocatalytic process described here has the advantage of less environmental pollution and thus has great potential for large-scale production of GlcN in an environment-friendly manner.

• Journal of Microbiology and Biotechnology
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• v.30 no.5
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• pp.762-769
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• 2020

Vitamin K2 (menaquinone) is an essential vitamin existing in the daily diet, and menaquinone-7 (MK-7) is an important form of it. In a recent work, we engineered the synthesis modules of MK-7 in Bacillus subtilis, and the strain BS20 could produce 360 mg/l MK-7 in shake flasks, while the methylerythritol phosphate (MEP) pathway, which provides the precursor isopentenyl diphosphate for MK-7 synthesis, was not engineered. In this study, we overexpressed five genes of the MEP pathway in BS20 and finally obtained a strain (BS20DFHG) with MK-7 titer of 415 mg/l in shake flasks. Next, we optimized the fermentation process parameters (initial pH, temperature and aeration) in an 8-unit parallel bioreactor system consisting of 300-ml glass vessels. Based on this, we scaled up the MK-7 production by the strain BS20DFHG in a 50-l bioreactor, and the highest MK-7 titer reached 242 mg/l. Here, we show that the engineered strain BS20DFHG may be used for the industrial production of MK-7 in the future.

• International Journal of Quality Innovation
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• v.10 no.1
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• pp.89-105
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• 2009

This study aims to probe into the influence of new product design and new product development process management on development performance. The research finding demonstrates that product design reveals positive and significant influence on new product development performance. Through statistical analysis, this study finds that companies in Taiwan value new product design. When companies value it more, they tend to have better new product development performance. With regard to the relation between new product development process management and new product development performance, the empirical results demonstrate that companies would pay more attention on new product development process management. With regard to new product idea and assessment, concept design and development, product function test and mass production in the market, through statistical analysis, this study finds that companies that value process management of new product development tend to have better new product development performance. As to the influence of new product design and new product process management on new product development performance, statistical analysis result demonstrates that the integration between new product design valued by companies in Taiwan and development process management would lead to significantly positive influence on new product development performance of the companies.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.9
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• pp.3680-3692
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• 2020

The purpose of this study is to orient users' touchpoints in co-design experience, to identify their need via visualized experience map, to recommend valid design information in online e-customization services. A user-centered co-design experience map (UCEM) is adopted to analyze the relation between users' desire and time spent, so as to evaluate the online co-design experiences. Based on evolutionary algorithm and fuzzy theory, data of this study is collected from 30 participants. The data was analyzed by descriptive analysis in SPSS, and frequency query and word cloud in NVivo. Employing design category and evaluating users' time spent, the findings are that (a) vamp color matching is consistent with interview data; (b) supported by qualitative feedback, the virtual experience map played an important role in the co-design process and the visualized interaction process; and (c) participants prefer to get more information and professional help on color matching and exterior design. Based on the findings in design category, future work should be focused on developing a better understanding of design resource recommendations and multi-stakeholder communication.