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Integration-centric approach to system readiness assessment based on evidential reasoning

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Journal of Systems Engineering and Electronics 2012年第6期23卷 881-890页

作者： Leilei Chang Mengjun Li ben Cheng Ping Zeng School of Information System and Management National University of Defense Technology Changsha 410073 P. R. China

An integration-centric approach is proposed to handle inadequate information in the system readiness level （SRL） assessment using the evidential reasoning （ER） algorithm. Current SRL assessment approaches cannot be applied to handle inadequate information as the input. The ER-based approach is proposed to synthesize inadequate input information and an integration-centric perspective is applied to reduce the computational complexity. Two case studies are performed to validate the efficiency of the proposed approach. And these studies are also performed to study how the inadequate information will affect the assessment result. And the differences caused by the system＇s structure. The importance of the system＇s structure in the SRL assessment is demonstrated and the contributions made in this study are summarized as conclusions.

关键词： system readiness level (SRL) technology readinesslevel (TRL) integration readiness level (IRL) evidential reasoning(ER) integration-centric.

A novel target detection approach based on adaptive radar waveform design

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Chinese Journal of Aeronautics 2013年第1期26卷 194-200页

作者： Wang Haitao Shi Lei Wang Youlin ben De Nanjing Research Institute of Electronics Technology

To resolve problems of complicated clutter, fast-varying scenes, and low signal-clutterratio （SCR） in application of target detection on sea for space-based radar （SBR）, a target detection approach based on adaptive waveform design is proposed in this paper. Firstly, complicated sea clutter is modeled as compound Gaussian process, and a target is modeled as some scatterers with Gaussian reflectivity. Secondly, every dwell duration of radar is divided into several sub-dwells. Regular linear frequency modulated pulses are transmitted at Sub-dwell 1, and the received signal at this sub-dwell is used to estimate clutter covariance matrices and pre-detection. Estimated matrices are updated at every following sub-dwell by multiple particle filtering to cope with fast-varying clutter scenes of SBR. Furthermore, waveform of every following sub-dwell is designed adaptively according to mean square optimization technique. Finally, principal component analysis and generalized likelihood ratio test is used for mitigation of colored interference and property of constant false alarm rate, respectively. Simulation results show that, considering configuration of SBR and condition of complicated clutter, 9 dB is reduced for SCR which reliable detection requires by this target detection approach. Therefore, the work in this paper can markedly improve radar detection performance for weak targets.

关键词： Adaptive waveform design Generalized likelihood ratio test Multiple particle filter Principal component analysis Radar systems Space-based radar

Palladium-phosphinous acid complexes catalyzed Suzuki cross-coupling reaction of heteroaryl bromides with phenylboronic acid in water/alcoholic solvents

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Journal of Environmental Sciences 2013年第6期25卷 1083-1088页

作者： ben Li Cuiping Wang Guang Chen Zhiqiang Zhang School of Chemical Engineering University of Science and Technology Liaoning

Highly active, air-stable and water-soluble palladium-phosphinous acid complexes have been applied to Suzuki cross-coupling reaction of heteroaryl bromides under mild conditions in water/alcoholic solvents. Suzuki cross-coupling reaction of heteroaryl bromides with phenylboronic acid occurred efficiently using palladium phosphinous acid complexes （POPd） and phase transfer catalyst （tetrabutylammonium bromide and polyethylene glycol） in water/ethanol mixture, water/propanol mixture and neat water respectively, the corresponding yields of cross-coupling heteroaryl-aryls were satisfied. The tert-butyl substituted ligand di-tert-butylphosphino in combination with POPd was found to be more active than the same family derived catalysts dipalladium complexes POPdl and POPd2, and other two kinds of Pd-catalysts Pd（PPh3）4 and Pd2（dba）3. The mechanism of Suzuki cross-coupling reaction between heteroaryl bromides and phenylboronic acid in water was proposed with respect to the key role of phase transfer catalyst on the transmetallation step. Compared with other solid phase transfer catalysts, TBAB was tested as the ideal one. The alkalinity of base and the molar proportion between POPd and TBAB were investigated in water and alcoholic solvents. Notably, in the presence of TBAB adding alcoholic solvents into water enhanced the yields of target products. However in terms of the liquid phase transfer catalyst of PEGs, mixing water into PEGs could slightly decrease the yields with respect to the water free PEGs bulk phase, which was probably due to the homogenous liquid conditions in pure PEGs and weak interactions between PEGs and heteroaryl bromide molecules in water depending on their molecular chain lengths.

关键词： POPd Suzuki cross-coupling reaction heteroaryl bromides phase transfer catalyst water

Revitalizing urban spaces: Ten key lessons from the “Viaduc des arts” adaptive reuse and placemaking

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Frontiers of Architectural Research 2024年第5期13卷 1095-1112页

作者： D.ben Ghida Department of Architecture University of Naples Federico Ⅱ NaplesNaplesItaly

This study focuses on the adaptive reuse and placemaking of the Viaduc des Arts,an obsolete viaduct in Paris,and examines its impact on the city’s economic,urban,cultural,and sustainable *** aims to showcase unconventional solutions applied to create an elevated linear park and a coherent commercial identity under the vaults while enhancing the district’s imageability and *** a mixed-methods approach,this study analyzes various action modes in architectural and urban regeneration,highlighting ten valuable lessons learned from the Viaduc des Arts *** lessons provide crucial insights into effective urban regeneration and placemaking strategies,emphasizing the need to update objectives and employ appropriate methodologies for future *** Viaduc des Arts serves as a paradigmatic case study,demonstrating the successful transformation of an obsolete viaduct into a commercial,vibrant cultural,and urban space,underscoring the importance of updating urban regeneration objectives.

关键词： Elevated parks Urban attractiveness Industrial heritage Urban identity Cultural heritage Building rehabilitation Urban regeneration Adaptive reuse strategies

A NOVEL ZWITTERIONIC SILANE COUPLING AGENT FOR NONTHROMBOGENIC BIOMATERIALS

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Chinese Journal of Polymer Science 2005年第6期23卷 611-617页

作者： Yong-zhi Qiu Dou-yong Min Chi ben Chi ben Qiang Chen Si-cong Lin Research Center of Surface ＆ Interface Chemistry and Engineering Technology Nanjing University Nanjing 210093 China College of Chemistry ＆ Environment Science Nanjing Normal University Nanjing 210097 China

A novel silane coupling agent bearing sulfobetaine group, N,N-diethyl-N-（3-sulfopropyl）-aminopropyl- trimethoxysilane （DESATS）, was first designed, synthesized and characterized. Its solution property was studied by means of dynamic light scattering. DESATS was successfully bonded onto the surface of the glass and proved by ESCA. Platelet adhesion assay in vitro indicated that the nonthrombogenicity of glass slide modified with DESATS is greatly improved.

关键词： Zwitterionic silane coupling agent Silicone-sulfobetaine Nonthrombogenic biomaterials

Model for the Whole Roller Leveling Process of Plates with Random Curvature Distribution Based on the Curvature Integration Method

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Chinese Journal of Mechanical Engineering 2019年第3期32卷 145-155页

作者： ben Guan Chao Zhang Yong Zang Yuan Wang School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China Institute of Artificial Intelligence University of Science and Technology BeijingBeijing 100083China

A model based on the curvature integration method has been applied in an online plate leveling system. However, there are some shortcomings in the current leveling models. On the one hand, the models cannot deal with the leveling process of plates with a random curvature distribution. On the other hand, the current models are suitable only for stable leveling processes and ignore the biting in and tailing out stages. This study presents a new plate-leveling model based on the curvature integration method, which can describe the leveling process of plates with random curvature distribution. Further, the model is solved in two cases in order to take the biting in and tailing out stages into consideration. The proposed model is evaluated by comparing with a plate leveling experiment. Finally, the leveling process of a plate with a wave bent is studied using the proposed model. It is found that the contact angles vary greatly during the biting in and tailing out stages. However, they are relatively steady during the 5 roller leveling stage. In addition, the contact angle of roller No. 2 is the smallest, which is close to 0. Roller leveling can effectively eliminate bending in the plate, but there are regions in the head and tail of the plate, where roller leveling is not effective. The non-leveling region length is about 2 times that of the roller space. This study proposes a quasi-static plate-leveling model, which makes it possible to analyze the dynamic straightening process using a curvature integration method. It also makes it possible to analyze the straightening process of a plate with random curvature distribution.

关键词： Leveling Curvature integration method Curvature Contact angle Deflection

Inter-comparative Study of Quantitative Methods of Industrial Clinker

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Journal of Wuhan University of Technology(Materials Science) 2017年第6期32卷 1250-1260页

作者： benmohamed Mohamed Galai Haykel Alouani Rabah Bejaoui Marouene ben Haj Amara Abdessalem ben Rhaim Hafsia UR05/13-01 Physique des Materiaux Lamellaires et Nanomateriaux Hybrides (PMLNMH) Faeulte des Sciences de Bizerte Universitede Carthage Zarzouna 7021 Tunisia Institut National de Recherche et d'Analyse Physico-chimiques 2026 Technopole de Sidi Thabet Tunisia

Impurities from the raw materials, the grinding and the homogenization of the raw materials, the kiln instability and the complexity of the cooling step, all these factors make it difficult to obtain a perfect evaluation of the mineralogical composition of Portland clinker. We studied the limitations of the most commonly used quantitative methods and recommend some procedures to obtain reliable and reproducible results of quantitative analyses. Different clinker samples（provided by the Bizerte Cement Company（Tunisia）） were subjected to an elemental analysis by X-ray fluorescence and the mineralogical composition was determined by the Bogue calculation and by X-ray powder diffraction combined with the Rietveld method（Different softwares were used： XPert High Score Plus version 2.0 and TOPAS version 4.2）. We then compared the results obtained by the Rietveld method and the Bogue calculation to the specific peak areas of each phase. The content of each phase, determined by the Rietveld method, varied proportionally to the change in peak area; a significant difference in these results was found by using the elementary Bogue calculation.

关键词： portland clinker bogue calculation rietveld method quantitative mineralogy specificpeaks different software

Spin-dependent transport properties and Seebeck effects for a crossed graphene superlattice p-n junction with armchair edge

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Frontiers of physics 2018年第4期13卷 145-157页

作者： ben-Hu Zhou ben-Liang Zhou Yang-Su Zeng Man-Yi Duan Guang-Hui Zhou Department of Physics Shaoyang University Shaoyang 422001 China Department of Physics and Key Laboratory for Low-Dimensional Structures and Quantum Manipulation (Ministry of Education) Hunan Normal University Changsha 410081 China College of Physics and Electronic Engineering Sichuan Normal University Chengdu 610068 China

Using the nonequilibrium Green＇s function method combined with the tight-binding Hamiltonian, we theoretically investigate the spin-dependent transmission probability and spin Seebeck coefficient of a crossed armchair-edge graphene nanoribbon （AGNR） superl＇attice p-n junction under a perpendicular magnetic field with a ferromagnetic insulator, where junction widths Wi of 40 and 41 are considered to exemplify the effect of semiconducting and metallic AGNRs, respectively. A pristine AGNR system is metallic when the transverse layer m = 3j ＋ 2 with a positive integer j and an insulator otherwise. When stubs are present, a semiconducting AGNR junction with width W1= 40 always shows metallic behavior regardless of the potential drop magnitude, magnetization strength, stub length, and per- pendicular magnetic field strength. However, metallic or semiconducting behavior can be obtained from a metallic AGNR junction with Wi = 41 by adjusting these physical parameters. Furthermore, a metal-to-semiconductor transition can be obtained for both superlattice p-n junctions by adjust- ing the number of periods of the superlattice. In addition, the spin-dependent Seebeck coefficient and spin Seebeck coefficient of the two systems are of the same order of magnitude owing to the appearance of a transmission gap, and the maximum absolute value of the spin Seebeck coefficient reaches 370 μV/K when the optimized parameters are used. The calculated results offer new possi- bilities for designing electronic or heat-spintronic nanodevices based on the graphene superlattice p-n junction.

关键词： crossed graphene superlattice p-n junction spin-dependent transport properties Seebeck coefficient nonequilibrium Green's function

Properties of BL Lac Objects with Redshift ≤ 0.2

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Chinese Journal of Astronomy and Astrophysics 2002年第1期2卷 8-16页

作者： ben－ZhongDai Guang－ZhongXie 等 YunnanObservatory ChineseAcademyofScienceKunming650011 NationalAstronomicalObservatories ChineseAcademyofScienceBeijing100012

We present a large sample which includes 82 BL Lac objects with red- shifts below 0.2 from recent literature. We find strong correlations in both flux and luminosity between the radio (5 GHz) and optical bands (5500 A). The correlations in other bands are very weak. Five TeV BL Lacs and two suspect sources are found to have similar properties as high- frequency- peaked BL Lacs (HBLs). Our results suggest that both the radio and optical emissions are from the same radiation mech- anism in the SSC model. The TeV BL Lac candidates should be HBLs or HBL-like objects with small redshifts.

关键词： galaxies: active - BL Lacertae objects: general -gamma-ray: observations - radiation mechanisms: non-thermal