检索结果-南通市图书馆

Imaginary Modules over the Affine Nappi-Witten Algebra

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2022年第6期38卷 1041-1053页

作者： Yi Xin bao yan An CAI School of Sciences Harbin Institute of Technology(Shenzhen)Shenzhen 518055P.R.China Department of Mathematics Soochow UniversitySuzhou 215006P.R.China

In this paper,we consider the imaginary highest weight modules and the imaginary Whittaker modules for the affine Nappi-Witten algebra.We show that simple singular imaginary Whittaker modules at level(κ、c)(κ∈C~*)are simple imaginary highest weight modules.The necessary and sufficient conditions for these imaginary modules to be simple are given.All simple imaginary modules are classified.

关键词： Affine Nappi-Witten algebra imaginary Verma modules imaginary highest weight modules imaginary Whittaker modules simple modules

Payload Symbol-Based Nonlinear RF Fingerprint for Wireless QPSK-OFDM Devices

在线全文

学校读者我要写书评

暂无评论

China Communications 2023年第6期20卷 240-248页

作者： Honglin Yuan yan yan Guoan Zhang Zhihua bao School of Information Science and Technology Nantong UniversityNantong 226019China Nantong Research Institute for Advanced Communication Technologies Nantong 226019China

Radio Frequency(RF) fingerprinting is one physical-layer authentication method for wireless communication, which uses the unique hardware characteristic of the transmitter to identify its true identity.To improve the performance of RF Fingerprint(RFF)based on preamble with fixed duration, a nonlinear RF fingerprinting method based on payload symbols is proposed for the wireless OFDM communication with the bit mapping scheme of QPSK. The wireless communication system is modeled as a Hammerstein system containing the nonlinear transmitter and multipath fading channel. A parameter separation technique based on orthogonal polynomial is presented for the estimation of the parameters of the Hammerstein system. The Hammerstein system parameter separation technique is firstly used to estimate the linear parameter with the training signal, which is used to compensate the adverse effect of the linear channel for the demodulation of the successive payload symbols. The demodulated payload symbols are further used to estimate the nonlinear coefficients of the transmitter with the Hammerstein system parameter separation technique again, which is used as the novel RFF for the authentication of the QPSK-OFDM device. Numerical simulations have verified the proposed method, which can also be extended to the OFDM signals with other bit mapping schemes.

关键词： physical-layer authentication RF Fingerprint RF Fingerprinting Hammerstein system parameter separation nonlinearity RFF spectrum sharing

Module Structures on U(ε^(-))for the Euclidean Algebra

在线全文

学校读者我要写书评

暂无评论

Algebra Colloquium 2024年第1期31卷 49-56页

作者： Yixin bao yan'an Cai School of Sciences Harbin Institute of Technology ShenzhenGuangdong 518055China Department of Mathematics Soochow University SuzhouJiangsu 215006China

We classify modules which are free of rank 1 when restricted to the negative part for the Euclidean Lie algebra.Sufficient and necessary conditions for the simplicity of these modules are given.From these modules we c... 详细信息

关键词： Euclidean algebra free module simple module nonweight module

A study on bearing characteristic and failure mechanism of thin-walled structure of a prefabricated subway station

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2022年第3期16卷 359-377页

作者： Lianjin TAO Cheng SHI Peng DING Sicheng LI Shang WU Yan Bao Key Laboratory of Urban Security and Disaster Engineering of the Ministry of Education Beijing University of TechnologyBeijing 100124China Department of Hydraulic Engineering Tsinghua UniversityBeijing 100084China China Construction Science&Technology Group Co. LtdBeijing 100195China

In order to study the bearing performance of a new type of prefabricated subway station structure(PSSS),firstly,a three-dimensional finite element model of the PSSS was established to study the nonlinear mechanics and deformation performance.Secondly,the bearing mechanism of a PSSS was investigated in detail.Finally,the development law of damages to a thin-walled prefabricated component and the failure evolution mechanism of a PSSS were discussed.The results showed that this new type of the PSSS had good bearing capacity.The top arch structure was a three-hinged arch bearing system,and the enclosure structure and the substructure were respectively used as the horizontal and vertical support systems of the three-hinged arch structure to ensure the integrity and stability of the overall structure.Moreover,the tongue-and-groove joints could effectively transmit the internal force between the components and keep the components deformed in harmony.The rigidity degradation of the PSSS caused by the accumulation of damages to the spandrel,hance,arch foot,and enclosure structure was the main reason of its loss of bearing capacity.The existing thin-walled components design had significant advantages in weight reduction,concrete temperature control,components hoisting,transportation and assembly construction,which achieved a good balance between safety,usability and economy.

关键词： prefabricated subway station thin-walled components finite element analysis bearing characteristic failure mechanism

Changes of DOM and its correlation with internal nutrient release during cyanobacterial growth and decline in Lake Chaohu, China

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2023年第2期124卷 769-781页

作者： Yan Bao Tao Huang Chengwu Ning Tingting Sun Pengliang Tao Jie Wang Qingye Sun School of Resources and Environmental Engineering Anhui UniversityHefei 230601China Anhui Province Key Laboratory of Wetland Ecosystem Protection and Restoration Anhui UniversityHefei 230601China

The seasonal changes in dissolved organic matter(DOM),and its correlation with the release of internal nutrients during the annual cycle of cyanobacteria in the eutrophic Lake Chaohu,China,were investigated from four sampling periods between November 2020 and July 2021.The DOM fluorescence components were identified as protein-like C1,microbial humic-like C2,and terrestrial humic-like C3.The highest total fluorescence intensity(FT)of DOM in sediments during the incubation stage is due to the decomposition and degradation of cyanobacteria remains.The lowest humification of DOM and the highest proportion of C1 in waters during the initial cyanobacterial growth indicate that fresh algae are the main source.The highest molecular weight of DOM and FT of the C2 in sediments during cyanobacterial outbreaks indicate the concurrent deposition of undegraded cyanobacterial remains and microbial degradation.The components of DOM are affected mainly by the dissolved total phosphorus in waters,while the temperature drives the annual cycle of cyanobacteria.The decreasing C1 in sediments and increasing nutrients in waters from the cyanobacterial incubation to outbreak indicate that mineralization of algal organic matter contributes importantly to the release of internal nutrients,with the strongest release of phosphorus observed during the early growth of cyanobacteria.The humic-like C2 and C3 components could also affect the dynamics of internal phosphorus through the formation of organic colloids and organic–inorganic ligands.The results show that the degradation of DOM leads to nutrients release and thus supports the continuous growth of cyanobacteria in eutrophic Lake Chaohu.

关键词： Eutrophication Shallow lake Sediment-water interface Algal blooms Fluorescence components PARAFAC

Comparison of surface integrity for dry and wet drilling of 49Fe-49Co-2V alloy

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2022年第6期35卷 325-338页

作者： Yuan ZHANG Zhigang DONG Yan Bao Renke KANG Xin HUANG Dongming GUO Key Laboratory for Precision and Non-traditional Machining Technology of the Ministry of Education School of Mechanical EngineeringDalian University of TechnologyDalian 116024China AVIC Xi’an Flight Automatic Control Research Institute Xi’an 710076China

Working performances of the components made out of 49Fe-49Co-2V alloy are closely related to the surface integrity of the drilled holes,which are influenced remarkably by the cooling conditions.The present study focuses on the surface integrity differences between wet and dry drilled 49Fe-49Co-2V alloy holes.The drilled hole surface roughness and topographies,metallurgical and mechanical properties,and the exit characterizations were obtained using optical microscopy(OM),scanning electron microscopy(SEM),electron backscatter diffraction microscopy(EBSD),transmission electron microscopy(TEM),energy dispersive spectroscopy(EDS)and Vickers hardness techniques,etc.The effects of cooling conditions on the surface integrity were concluded and the influence mechanisms were analyzed based on the force and temperature differences in drilling process with different cooling conditions.It is found that the surface roughness and the thickness of refined-grain region of the dry drilled holes are larger than those of wet drilled holes;work hardening induced by wet drilling is more serious than dry drilling;chippings occurred in the exits of the wet drilled holes due to the material brittleness,which could be avoided by dry drilling.The surface integrity differences of wet and dry drilled holes are closely related to the force and temperature differences in drilling process with different cooling conditions.

关键词： 49Fe-49Co-2V alloy Cooling condition Drilling Exit chipping Microstructure Surface integrity Surface quality Work hardening

Evolution and innovation of antenna systems for beyond 5G and 6G

在线全文

学校读者我要写书评

暂无评论

Frontiers of Information Technology & Electronic Engineering 2020年第1期21卷 1-3页

作者： bao-yan DUAN Research Institute on Mechatronics Xidian UniversityXi’an 710071China

With the advance of the 5^th generation(5G)wireless communication system in recent years,5G network construction and terminal equipment have gradually been finalized and entered the commercial stage.The 6^th generation(6G)mobile communication system has become a promising and important area with both academic and industrial concerns.Compared with 5G,6G will achieve higher access rate(10–100 times higher),lower access delay,as well as wider and deeper communication coverage,with much better energy and spectrum efficiency.It enables the material,process,technology,and forms of antenna and radio frequency(RF)systems to evolve continuously.There are several important tendencies in the development of antenna and RF systems.

关键词： antenna communication beyond

Error Analysis of A New Higher Order Boundary Element Method for A Uniform Flow Passing Cylinders

在线全文

学校读者我要写书评

暂无评论

China Ocean Engineering 2023年第3期37卷 369-377页

作者： SUN Shi-yan CUI Jie bao Chao-ming School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

A higher order boundary element method(HOBEM)is presented for inviscid flow passing cylinders in bounded or unbounded domain.The traditional boundary integral equation is established with respect to the velocity potential and its normal derivative.In present work,a new integral equation is derived for the tangential velocity.The boundary is discretized into higher order elements to ensure the continuity of slope at the element nodes.The velocity potential is also expanded with higher order shape functions,in which the unknown coefficients involve the tangential velocity.The expansion then ensures the continuities of the velocity and the slope of the boundary at element nodes.Through extensive comparison of the results for the analytical solution of cylinders,it is shown that the present HOBEM is much more accurate than the conventional BEM.

关键词： higher order boundary element method(HOBEM) error analysis integral equations for potential and velocity cylinders

High levels of glucose induce epithelial-mesenchymal transition in renal proximal tubular cells through PERK-eIF2αpathway

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2019年第7期132卷 868-872页

作者： Yan Bao Ying Ao Bo Yi Jo Batubayier Department of Endocrinology Renmin Hospital of Wuhan UniversityWuhanHubei 430060China Department of Pharmacology School of Basic Medical ScienceWuhan UniversityWuhanHubei 430071China Department of Internal medicine Hoboksar Mongol Autonomous County HospitalTachengXinjiang 834499China

To the Editor:Diabetic kidney disease (DKD) is one of the major causes of end-stage renal failure.Progressive mesangial expansion in the glomerulus is widely recognized.More and more evidence shows that tubulointerstitial fibrosis is also regarded as a prominent feature of DKD,in which tubular epithelial-mesenchymal transition (EMT) may play an important role.[1] During EMT,tubular epithelial cells lose their characteristic and produce high levels of myofibroblast makers such as α-smooth actin (α-SMA) which is the signature protein of EMT.[2]However,renal fibrogenesis is a complicated process in which the contribution of DKD is unknown.

关键词： cells ep protein is tra EMT