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One Parameter Deformation of Symmetric Toda Lattice Hierarchy

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Communications in Mathematical Research 2018年第1期34卷 47-53页

作者： xiong zhen Department of Mathematics and Computer Yichun University

In this paper, we study one parameter deformation of full symmetric Toda hierarchy. This deformation is induced by Hom-Lie algebras, or is the applications of Hom-Lie algebras. We mainly consider three kinds of deform... 详细信息

关键词： Hom-Lie algebra deformation symmetric Toda hierrchy

Development of a PC-based Open Architecture Software-CNC System

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Chinese Journal of Aeronautics 2007年第3期20卷 272-281页

作者： MA xiong-bo HAN zhen-yu WANG Yong-zhang FU Hong-ya School of Electromechanical Engineering Harbin Institute of Technology Harbin 150001 China

As a key te..hnology in the field of advanced manufacturing, an open architecture controller is studied. In order to develop an open architecture software-CNC system on personal computer （PC） according to open modular architecture controllers （OMAC）. First, the software and hardware platform is chosen and software realization methodology for the CNC system is determined. Second, static modeling methods of an open architecture controller inclusive of object-oriented （OO） programming technology, dynamic link library （DLL） technology and system modules partition are investigated. Third, the dynamical behavioral modeling and the data flow representation of open architecture controller are discussed, which are both described in hierarchy fmite state machine （FSM） model. Fourth, a reusable software module model is established to develop software function module library. Finally, a 3-axis milling machine tool test-bed, named for HIT-CNC, is successfully designed by means of the constructed software function module library and the system configuring method. The experimental results show that, besides increasing the degree of reusability and openness, application of above-mentioned method- ology leads to significant decrease of development time as well as maintenance cost.

关键词： open architecture controller PC soflware-CNC behavioral model OMAC machine tool

Anomalous Kondo-Switching Effect of a Spin-Flip Quantum Dot Embedded in an Aharonov-Bohm Ring

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Communications in Theoretical Physics 2009年第11期52卷 945-948页

作者： CHEN xiong-Wen SHI zhen-Gang SONG Ke-Hui Department of Physics and Electronic Information Science Huaihua University Huaihua 418008 China

We theoretically investigate the Kondo effect of a quantum dot embedded in a mesoscopic Aharonov-Bohm （AIR） ring in the presence of the spin flip processes by means of the one-impurity Anderson Hamiltonian. Based on the slave-boson mean-field theory, we find that in this system the persistent current （PC） sensitively depends on the parity and size of the AB ring and can be tuned by the spin-flip scattering （R）. In the small AB ring, the PC is suppressed due to the enhancing R weakening the Kondo resonance. On the contrary, in the large AB ring, with R increasing, the peak of PC firstly moves up to max-peak and then down. Especially, the PC phase shift of π appears suddenly with the proper value of R, implying the existence of the anomalous Kondo effect in this system. Thus this system may be a carldidate for quantum switch.

关键词： persistent current quantum dot Kondo effect spin-flip scattering effect

Neurite Orientation Dispersion and Density Imaging of Rat Brain Microstructural Changes due to Middle Cerebral Artery Occlusion at a 3T MRI

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Current Medical Science 2021年第1期41卷 167-172页

作者： zhen-xiong WANG Wen-zhen ZHU Shun ZHANG Mehran Shaghaghi Ke-jia CAi Department of Radiology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Department of Radiology Department of Bioengineeringand the Center for MR ResearchUniversity of Illinois at ChicagoChicago60612USA

The purpose of this work was to demonstrate the feasibility of neurite orientation dispersion and density imaging(NODDI)in characterizing the brain tissue microstructural changes of middle cerebral artery occlusion(MCAO)in rats at 3T MRI,and to validate NODDI metrics with histology.A multi-shell diffusion MRI protocol was performed on 11 MCAO rats and 10 control rats at different post-operation time points of 0.5,2,6,12,24 and 72 *** orientation dispersion index(ODI)and intracellular volume fraction(V_(ic))metrics were compared between MCAO group and control *** evolution of NODDI metrics was characterized and validated by *** was consistent with significantly increased ODI and V_(ic)in comparison to control tissues at all time points(P<0.001).Lesion ODI increased gradually from 0.5 to 72 h,while its V_(ic)showed a more complicated and fluctuated *** and V_(ic)were significantly different between hyperacute and acute stroke periods(P<0.001).The NODDI metrics were found to be consistent with the histological *** conclusion,NODDI can reflect microstructural changes of brain tissues in MCAO rats at 3T MRI and the metrics are consistent with *** study helps to prepare NODDI for the diagnosis and management of ischemic stroke in translational research and clinical practice.

关键词： diffusion magnetic resonance imaging neurite orientation dispersion and density imaging middle cerebral artery occlusion model stroke rats

Noninvasive Characterization of Metabolic Changes in Ischemic Stroke Using Z-spectrum-fitted Multiparametric Chemical Exchange Saturation Transfer-weighted Magnetic Resonance Imaging

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Current Medical Science 2023年第5期43卷 970-978页

作者： zhen-xiong WANG Xin-hua WEI Ke-jia CAI Wen-zhen ZHU Chang-liang SU Department of Radiology Guangzhou First People’s HospitalSchool of MedicineSouth China University of TechnologyGuangzhou 510180China Department of Radiology Department of Bioengineeringand The Center for MR ResearchUniversity of Illinois at ChicagoChicago 60612USA Department of Radiology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Radiology Sun Yat-sen University Cancer CenterState Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer MedicineGuangzhou 510060China

Objective This study aimed to noninvasively characterize the metabolic alterations in ischemic brain tissues using Z-spectrum-fitted multiparametric chemical exchange saturation transfer-weighted magnetic resonance imaging(CEST-MRI).Methods Three sets of Z-spectrum data with saturation power(B_(1))values of 1.5,2.5,and 3.5µT,respectively,were acquired from 17 patients with ischemic *** contrasts contributing to the Z-spectrum,including fitted amide proton transfer(APT_(fitted)),+2 ppm peak(CEST@2ppm),concomitantly fitted APT_(fitted) and CEST@2ppm(APT&CEST@2ppm),semisolid magnetization transfer contrast(MT),aliphatic nuclear Overhauser effect(NOE),and direct saturation of water(DSW),were fitted with 4 and 5 Lorentzian functions,*** CEST metrics were compared between ischemic lesions and contralateral normal white matter(CNWM),and the correlation between the CEST metrics and the apparent diffusion coefficient(ADC)was *** differences in the Z-spectrum metrics under varied B1 values were also *** Ischemic lesions showed increased APTfitted,CEST@2ppm,APT&CEST@2ppm,NOE,and DSW as well as decreased ***&CEST@2ppm,MT,and DSW showed a significant correlation with ADC[APT&CEST@2ppm at the 3 B_(1) values:R=0.584/0.467/0.551;MT at the 3 B_(1) values:R=−0.717/−0.695/−0.762(4-parameter fitting),R=−0.734/−0.711/−0.785(5-parameter fitting);DSW of 4-/5-parameter fitting:R=0.794/0.811(2.5µT),R=0.800/0.790(3.5µT)].However,the asymmetric analysis of amide proton transfer(APT_(asym))could not differentiate the lesions from CNWM and showed no correlation with ***,the Z-spectrum contrasts varied with B_(1).Conclusion The Z-spectrum-fitted multiparametric CEST-MRI can comprehensively detect metabolic alterations in ischemic brain tissues.

关键词： chemical exchange saturation transfer Z-spectrum ischemic stroke

Texture classification based on EMD and FFT

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第9期7卷 1516-1521页

作者： xiong Chang-zhen XU Jun-yi ZOU Jian-cheng QI Dong-xu School of Information Science and Technology Sun Yat-sen University Guangzhou 510275 China Information Science School Guangdong University of Business Studies Guangzhou 510320 China College of Science North China University of Technology Beijing 100041 China

Empirical mode decomposition (EMD) is an adaptive and approximately orthogonal filtering process that reflects human’s visual mechanism of differentiating textures. In this paper, we present a modified 2D EMD algorithm using the FastRBF and an appropriate number of iterations in the shifting process (SP), then apply it to texture classification. Rotation-invariant texture feature vectors are extracted using auto-registration and circular regions of magnitude spectra of 2D fast Fourier transform (FFT). In the experiments, we employ a Bayesion classifier to classify a set of 15 distinct natural textures selected from the Brodatz album. The experimental results, based on different testing datasets for images with different orientations, show the effectiveness of the proposed classification scheme.

关键词： Texture classification Empirical mode decomposition (EMD) Fourier transform Auto-registration Rotationinvariant

Texture evolution of commercial pure Ti during cold rolling and recrystallization annealing

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International Journal of Minerals,Metallurgy and Materials 2012年第6期19卷 530-535页

作者： Hai-tao Jiang Ji-xiong Liu zhen-li Mi Ai-min Zhao Yan-jun Bi Metallurgical Engineering Research Institute University of Science and Technology Beijing Beijing 100083 China

X-ray diffraction （XRD） was employed to analyze the texture evolution of commercial pure （CP） Ti during cold rolling and re- crystallization annealing. The texture components were measured by electron backscattered diffraction （EBSD） after recrystallization an- nealing. The CP Ti tends to form a texture with the basal pole tilted 30°-40° away from the normal direction toward the transverse direction. The texture of the initial hot-rolled plate can be classified into three kinds, i.e., the pyramid texture （1013）[5230] and （2021）[1015], the basal plane texture （0001）[2110], and the stronger_prism_texture （1120）[0001]. After cold rolling and annealing （700℃,60 min）,_the main texture components are the cold-rolled texture （1125）[1123] and the recrystallized texture （1013）[5230]. The texture （2021）[1015] is in- herited from the texture of the initial hot-rolled plate with the decrease of orientation density gradually. The volume contents of the cold-rolled texture {2115}（0110） and the recrystallized texture {1013}（1210） are calculated by EBSD. After recrystallization annealing, the specimen is rich in the recrystallized texture and inherits some of texture components from the cold-rolled texture. When the annealing time is prolonged, the anisotropic value decreases.

关键词： titanium cold rolling recrystallization annealing textures

Monitoring and Prediction of the Vibration Intensity of Seismic Waves Induced in Underwater Rock by Underwater Drilling and Blasting

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Defence Technology（防务技术） 2022年第1期18卷 109-118页

作者： zhen-xiong Wang Wen-bin Gu Ting Liang Shou-tian Zhao Peng Chen Liu-fang Yu Research Institute of Chemical Defence 102205 China Armry Engineering University 210007China Archives Department of Space System100094China

All underwater drilling and blasting operations generate seismic ***,due to a lack of suitable vibration sensing instruments,most studies on the propagation of seismic waves have been limited to shorelines near construction areas or wharfs,whereas comparatively few studies have beerconducted on the larger seafloor *** address this gap,a seafloor vibration sensor system was developed and applied in this study that consists of an autonomous acquisition storage terminal,soft-ware platform,and hole-plugging device that was designed to record the blasting vibration intensities received through submarine rocks at a given measurement ***,dimensional analyses were used to derive a predictive equation for the strength of blast vibrations that considered the in fluence of the water *** combining reliable vibration data obtained using the sensor system in submarine rock and the developed predictive equation,it was determined that the water depth was ar important factor influencing the measured vibration *** results using the newly derivedequation were compared to those determined using the Sadowski equation,which is commonly used on land,and it was found that predictions using the derived equation were closer to the experimental values with an average error of less than 10%,representing a significant *** on these results the developed sensor system and preliminary theoretical basis was deemed suitable for studying the propagation behavior of submarine seismic waves generated by underwater drilling and blasting operations.

关键词： Seismic wave Underwater drilling and blasting Blasting vibration Dimensional analysis Induced seismicity

Effect of explosive noise on gastrointestinal transit and plasma levels of polypeptide hormones

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World Journal of Gastroenterology 2006年第14期12卷 2284-2287页

作者： zhen-Bin Mu Yu-Xin Huang Bao-Min Zhao zhen-xiong Liu Bing-Hua Zhang Qing-Li Wang Department of Gastroenterology Tang Du Hospital of the Fourth Military Medical University Xi'an 710038 Shaanxi Province China

AIM： To investigate the effect of firing noise on gastrointestinal transit and probe its mechanism by measuring the levels of plasma polypeptide hormones. METHODS： A total of 64 SD rats were randomly divided into a control group and three stimulating groups. Firing noise of different intensity by sub-machine guns was used as inflicting factor. The effect of firing noise on liquid substance gastrointestinal transit and solid substance gastrointestinal transit was observed by measuring the ratio of carbon powder suspension transmitting and barium sticks transmitting respectively. Plasma levels of polypeptide hormones were measured by radio-immunoassay. RESULTS： The noise accelerated gastrointestinal transit of solid food by more than 80 db;and accelerated gastrointestinal transit of liquid food significantly by more than 120 db. Meantime, plasma levels of plasma motilin （MTL）（157.47±16.08; 151.90±17.08）, somatostatin （SS）（513.97±88.77; 458.25±104.30）, substance P （SP）（115.52±20.70; 110.28±19.96） and vasoactive intestinal peptide （VIP）（214.21±63.17; 251.76±97.24） remarkably changed also. CONCLUSION： Within a certain intensity range, the firing noise changes the levels of rat plasma gastrointestinal hormones, but the gastrointestinal transit is still normal. Beyond the range, the noise induces plasma hormone levels disturbance and gastrointestinal transit disorder. ~

关键词： Explosive noise Gastrointestinal transit Gastrointestinal hormone