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Property(ω) and Its Perturbations

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Acta Mathematica Sinica,English Series 2014年第5期30卷 797-804页

作者： wei juan SHI Xiao Hong CAO College of Mathematics and Information Science Shaanxi Normal University

Abstract A Hilbert space operator T is said to have property （ω1） if σα（T）／σaw（T） π00（T）, where σα（T） andσαw（T） denote the approximate point spectrum and the Weyl essential approximate point spectrum of T respectively, and π00（T） ---- {λ∈ iso σ（T）, 0 〈 dim N（T- λI）〈 ∞}. Ifσα（T）／σαw（T） = π00（T）, we say T satisfies property （w）. In this note, we investigate the stability of the property （wi） and the property （w） under compact perturbations, and we characterize those operators for which the property （wi） and the property （w） are stable under compact perturbations.

关键词： Property (ω1) property (ω) compact perturbations

Algorithm for source recovery in underdetermined blind source separation based on plane pursuit

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Journal of Systems Engineering and Electronics 2018年第2期29卷 223-228页

作者： FU weihong wei juan LIU Naian CHEN Jiehu State Key Lab of Integrated Service Networks Xidian University No.10 Research Institution China Electronics Technology Group Corporation

In order to achieve accurate recovery signals under the underdetermined circumstance in a comparatively short time,an algorithm based on plane pursuit(PP) is proposed. The proposed algorithm selects the atoms according to the correlation between received signals and hyper planes, which are composed by column vectors of the mixing matrix, and uses these atoms to recover source signals. Simulation results demonstrate that the PP algorithm has low complexity and higher accuracy as compared with basic pursuit(BP), orthogonal matching pursuit(OMP), and adaptive sparsity matching pursuit(ASMP) algorithms.

关键词： underdetermined blind source separation(UBSS) source recovery greedy algorithm plane pursuit

Is Acupuncture Actually Not Effective for Polycystic Ovary Syndrome?--Analysis of the Trial Published in JAMA

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Chinese Journal of Integrative Medicine 2017年第12期23卷 883-886页

作者： GANG wei-juan JING Xiang-hong Institute of Acupuncture and Moxibustion China Academy of Chinese Medical SciencesBeijing 100700China

In recent years, acupuncture has been applied to treat more and more patients suffering from polycystic ovary syndrome(PCOS). On June 27, 2017 a paper titled 'Effect of acupuncture and clomiphene in Chinese women with polycystic ovary syndrome: a randomized clinical trial' was published in Journal of the American Medical Association(JAMA). The results did not support acupuncture as an effective therapy for improving the live births in PCOS. The aim of this article was to analyze the therapeutic regimen and design of the clinical trial. The primary outcome and the conclusion of the paper were discussed as well. There are 5 doubts in the paper.(1) The therapeutic regimen decided by trigger points in the paper was different from that of the traditional Chinese acupuncture.(2) The live birth as the primary outcome was limited during the PCOS recovery.(3) In addition the period of the treatment was too short to reflect the therapeutic effect.(4) Although there was no significant difference between active acupuncture and control acupuncture, the conclusion that acupuncture was not effective for PCOS was not confirmed because the control acupuncture plus clomiphene was also more effective than that of clomiphene alone.(5) The proposal and the statistics were not in accordance with the one planned before. Therefore the result was worth to be discussed so as to provide some suggestions and references for improving the clinical research of acupuncture.

关键词： acupuncture therapy polycystic ovary syndrome clinical trial regimen

Shear Banding Driven by Electric Field and Shear Flow

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Chinese Physics Letters 2013年第9期30卷 80-84页

作者： ZHENG Jie FU wei-juan ZHOU Lu-wei State Key Laboratory of Surface Physics and Department of PhysicsFudan UniversityShanghai 200433

The shear banding is explored in a granular suspension driven by electric field and shear *** find that,given an imposed electric field,there is a critical shear rate determining whether shear banding emerges.A phase diagram of shear banding and fluidization is constructed by using the present experimental *** evolution in different shear banding phases constitutes an apparent shear thinning phenomenon,probably reflecting an underlying perspective of shear *** the two-phase model,combining with mean field approach and the Onsager least dissipation principle,we give a qualitative explanation of our experimental *** results suggest that the stress heterogeneity plays a crucial role for the physical origin of shear banding in this system.

关键词： flow. Shear qualitative

A neurovascular unit-on-a-chip:culture and differentiation of human neural stem cells in a three-dimensional microfluidic environment

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Neural Regeneration Research 2022年第10期17卷 2260-2266页

作者： Wen-juan wei Ya-Chen Wang Xin Guan wei-Gong Chen Jing Liu Stem Cell Clinical Research Center National Joint Engineering LaboratoryRegenerative Medicine Centerthe First Affiliated Hospital of Dalian Medical UniversityDalianLiaoning ProvinceChina Dalian Innovation Institute of Stem Cell and Precision Medicine DalianLiaoning ProvinceChina

Biological studies typically rely on a simple monolayer cell culture,which does not reflect the complex functional characteristics of human tissues and organs,or their real response to external *** technology has advantages of high-throughput screening,accurate control of the fluid velocity,low cell consumption,long-term culture,and high *** combining the multipotential differentiation of neural stem cells with high throughput and the integrated characteristics of microfluidic technology,an in vitro model of a functionalized neurovascular unit was established using human neural stem cell-derived neurons,astrocytes,oligodendrocytes,and a functional microvascular *** model comprises a multi-layer vertical neural module and vascular module,both of which were connected with a syringe *** provides controllable conditions for cell inoculation and nutrient supply,and simultaneously simulates the process of ischemic/hypoxic injury and the process of inflammatory factors in the circulatory system passing through the blood-brain barrier and then acting on the nerve tissue in the *** in vitro functionalized neurovascular unit model will be conducive to central nervous system disease research,drug screening,and new drug development.

关键词： (neural)differentiation astrocyte blood-brain barrier brain microvascular endothelial cells central nervous system microfluidics neural stem cells neuron neurovascular unit oligodendrocyte organ-on-a-chip

Distance Between α-Orientations of Plane Graphs by Facial Cycle Reversals

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Acta Mathematica Sinica,English Series 2019年第4期35卷 569-576页

作者： wei juan ZHANG Jian Guo QIAN Fu Ji ZHANG School of Mathematical Sciences Xiamen University School of Mathematical Sciences Xinjiang Normal University

Cycle reversal had been shown as a powerful method to deal with the relation among orientations of a graph since it preserves the out-degree of each vertex and the connectivity of the orientations. A facial cycle reversal on an orientation of a plane graph is an operation that reverses all the directions of the edges of a directed facial cycle. An orientation of a graph is called an α-orientation if each vertex admits a prescribed out-degree. In this paper, we give an explicit formula for the minimum number of the facial cycle reversals needed to transform one α-orientation into another for plane graphs.

关键词： α-Orientation facial cycle reversal distance plane graph

Cubic vertex-transitive non-Cayley graphs of order 12p

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Science China Mathematics 2018年第6期61卷 1153-1162页

作者： wei-juan Zhang Yan-Quan Feng Jin-Xin Zhou Department of Mathematics Beijing Jiaotong University Beijing 100044 China

A graph is said to be vertex-transitive non-Cayley if its full automorphism group acts transitively on its vertices and contains no subgroups acting regularly on its vertices. In this paper, a complete classification of cubic vertex-transitive non-Cayley graphs of order 12 p, where p is a prime, is given. As a result, there are 11 sporadic and one infinite family of such graphs, of which the sporadic ones occur when p equals 5, 7 or 17, and the infinite family exists if and only if p ≡ 1(mod 4), and in this family there is a unique graph for a given order.

关键词： Cayley graphs vertex-transitive graphs automorphism groups

A Robust and Efficient Compressed Sensing Algorithm for Wideband Acoustic Imaging

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Chinese Journal of Mechanical Engineering 2020年第6期33卷 77-92页

作者： Fangli Ning Zhe Liu Jiahao Song Feng Pan Pengcheng Han juan wei School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an710072China Dongguan Sanhang Military-Civil Integration Innovation Research Institute Dongguan523808China School of Communication Engineering Xidian UniversityXi’an710071China

Wideband acoustic imaging,which combines compressed sensing(CS)and microphone arrays,is widely used for locating acoustic ***,the location results of this method are unstable,and the computational efficiency is *** this work,in order to improve the robustness and reduce the computational cost,a DCS-SOMP-SVD compressed sensing method,which combines the distributed compressed sensing using simultaneously orthogonal matching pursuit(DCS-SOMP)and singular value decomposition(SVD)is *** performance of the DCS-SOMP-SVD is studied through both simulation and *** the simulation,the locating results of the DCS-SOMP-SVD method are compared with the wideband BP method and the DCS-SOMP *** terms of computational efficiency,the proposed method is as efficient as the DCS-SOMP method and more efficient than the wideband BP *** terms of locating accuracy,the proposed method can still locate all sources when the signal to noise ratio(SNR)is−20 dB,while the wideband BP method and the DCS-SOMP method can only locate all sources when the SNR is higher than 0 *** performance of the proposed method can be improved by expanding the frequency ***,there is no extra source in the maps of the proposed method,even though the target sparsity is ***,a gas leak experiment is conducted to verify the feasibility of the DCS-SOMP-SVD method in the practical engineering *** experimental results show that the proposed method can locate both two leak sources in different frequency *** research proposes a DCS-SOMP-SVD method which has sufficient robustness and low computational cost for wideband acoustic imaging.

关键词： Wideband acoustic imaging Compressed sensing Singular value decomposition Microphone array Gas leakage

Failure Mechanism and Material Requirements for Coal Lance in Blast Furnace

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Journal of Iron and Steel Research International 2012年第4期19卷 11-16页

作者： XIONG wei JIA juan CHEN Jia-chao SHANG He-ming Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and Technology Wuhan 430081 Hubei China

Pulverized coal injection（PCI） is a key technology in modern ironmaking by blast furnace（BF） and the life of injection lance has a great influence on PCI operation and on normal running of blast *** is found that the main reasons for the failure of the lances are their outer surface oxidation and the inner surface erosion through monitoring some lances used in *** outer surface oxidation of the lances made of lCr18Ni9Ti is inevitable under high hot blast temperature condition through thermodynamics analysis.A mathematical model for calculating the temperature of common monocular coal lance had been developed according to the principles of mass and energy *** temperature and flow velocity of the hot blast would cause a rise in the lance *** influence of hot blast temperature is more *** lance temperature would decline when compressed air flux *** technology of dense phase pulverized coal is beneficial to extending lance’s life because decreasing solid-gas ratio would intensify erosion and burning *** anti-oxidation temperature of lance materials needs to be over 1000 ℃ for BF intensified *** order to increase the resistance to oxidation of the coal lance’s outer surface,oxidation-resistant steel or Al coating stainless steel is the appropriate material for BF *** the metal surface treatment technology to enhance the hardness of the coal lance’s internal surface could prolong the service life of coal lance

关键词： blast furnace coal lance failure mechanism material requirements