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On a Conformally Invariant Integral Equation Involving Poisson Kernel

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Acta Mathematica Sinica,English Series 2018年第4期34卷 681-690页

作者： jin Gang xiong School of Mathematical sciences Beijing Normal University

We study a prescribing involving Poisson kernel on the unit of PDE. As in Nirenberg problem, solutions. We prove existence in the functions problem of a conformally invariant integral equation ball. This integral equation is not the dual of any standard type there exists a Kazdan-Warner type obstruction to existence of antipodal symmetry functions class.

关键词： Poisson kernel conformal invariance blow up analysis

Quasi-Newton method based control design for unknown nonlinear systems with input constraints

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Science China(Information Sciences) 2020年第5期63卷 224-226页

作者： Shuangshuang xiong Zhongsheng hou Chenkun YIN Advanced Control Systems Lab School of Electronic and Information EngineeringBeijing Jiaotong University School of Automation Qingdao University

Dear editor,With the development in digital computers, various and huge data of controlled plants are obtained and stored, which has led to a rapid growth in the application of numerical methods in controller design. In recent years, the quasi-Newton method [1, 2], as one of the powerful numerical methods which has superlinear convergence speed

关键词： Newton Quasi-Newton method based control design for unknown nonlinear systems with input constraints

Design of Copper Oxide Nanosheets-Loaded Zeolite with Efficient Inhibition of Marine Bacteria

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Journal of Ocean University of China 2022年第5期21卷 1237-1243页

作者： hou jin YE Yongcheng Key Laboratory of Marine Chemistry Theory and Technology Ministry of EducationCollege of Chemistry and Chemical EngineeringOcean University of ChinaQingdao 266100China Shandong Key Laboratory of Corrosion Science Institute of OceanologyChinese Academy of SciencesQingdao 266100China

Copper oxide-loaded zeolite 4A nanocomposites(CuO-zeolite NCs)were successfully prepared by modifying zeolite 4A with CuSO_(4)aqueous solution as the copper *** 4A showed an important role in hosting copper oxide,and CuO-zeolite NCs exhibited a controlled release of copper *** patterns confirmed the appearance of new diffraction peaks of copper oxide at 35.83°and 38.83°.CuO nanosheets formed on the surface of zeolite 4A were about 30–40 nm thick over a width of 200–300 ***-zeolite NCs were primarily composed of Cu,Si,Al and O,as measured by *** 2p_(3/2) and Cu 2p_(1/2) peaks were fitted into two main peaks centered at 934.7 eV and 954.6 eV,which were attributed to Cu(II).Zeolite 4A and CuO-zeolite NC displayed reversible Langmuir isotherm(type-I)characteristics and showed maximum adsorption quantities of almost 200 cm^(3) g^(−1) at a relative pressure of 1.0 by CO_(2)adsorption-desorption *** antibacterial efficiencies of the CuO-zeolite NC were 99.4%,96.7%,and 96.8%against Pseudoalteromonas tetraodonis(***),Micrococcus luteus(***),and Shewanella putrefaciens(***),*** values showed that nano CuO-loaded zeolite 4A acted as a strong bactericide against marine ***-zeolite NCs can be further applied to marine antifouling coating.

关键词： antibacterial activities marine bacteria copper oxide nanosheets zeolite

Separability for Positive Operators on Tensor Product of Hilbert Spaces

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Acta Mathematica Sinica,English Series 2021年第6期37卷 893-910页

作者： jin Chuan hou jin Fei CHAI College of Mathematics Taiyuan University of TechnologyTaiyuan 030024P.R.China

The separability and the entanglement(that is,inseparability)of the composite quantum states play important roles in quantum information ***,a quantum state is a trace-class positive operator with trace one acting on a complex separable Hilbert *** this paper,in more general frame,the notion of separability for quantum states is generalized to bounded positive operators acting on tensor product of Hilbert ***,not like the quantum state case,there are different kinds of separability for positive operators with different operator *** types of such separability are discussed;several criteria such as the finite rank entanglement witness criterion,the positive elementary operator criterion and PPT criterion to detect the separability of the positive operators are established;some methods to construct separable positive operators by operator matrices are *** may also make us to understand the separability and entanglement of quantum states better,and may be applied to find new separable quantum states.

关键词： Hilbert spaces tensor products positive operators separability entanglement

Observations and modeling of flat subduction and its geological effects

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Science China Earth Sciences 2020年第8期63卷 1069-1091页

作者： Zhiyong YAN Lin CHEN xiong xiong Kai WANG Renxian XIE hou Tze HSU MOE Key Laboratory of Fundamental Physical Quantities Measurement&Hubei Key Laboratory of Gravitation and Quantum Physics PGMF and School of PhysicsHuazhong University of Science and TechnologyWuhan 430074China Institute of Geophysics and PGMF Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Geodesy and Earth s Dynamic Institute of Geodesy and GeophysicsChinese Academy of SciencesWuhan 430077China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Institute of Geophysics and Geomatics China University of GeosciencesWuhan 430074China

Flat subduction refers to low-angle(<10°) or sub-horizontal subduction of oceanic slabs. Flat subduction is only recognized in ~10% of present-day subduction zones, but its impact on the behavior of the overriding pl... 详细信息

Flat subduction refers to low-angle(hould carry out three-dimensional high-resolution thermo-mechanical simulation, considering the influence of crustal eclogitization(negative buoyancy) and mantle serpentinization(positive buoyancy) of oceanic lithosphere, in combination with geological and geophysical data.

关键词： Flat subduction Magmatism Intracontinental orogeny Formation mechanism Numerical modeling

Multi-Objective Multi-Variable Large-Size Fan Aerodynamic Optimization by Using Multi-Model Ensemble Optimization Algorithm

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Journal of Thermal Science 2024年第3期33卷 914-930页

作者： xiong jin GUO Penghua LI jingyin School of Energy and Power Engineering Xi’an Jiaotong UniversityXi’an710049China

The constrained multi-objective multi-variable optimization of fans usually needs a great deal of computational fluid dynamics(CFD)calculations and is *** this study,a new multi-model ensemble optimization algorithm is proposed to tackle such an expensive optimization *** multi-variable and multi-objective optimization are conducted with a new flexible multi-objective infill *** addition,the search direction is determined by the multi-model ensemble assisted evolutionary algorithm and the feature extraction by the principal component analysis is used to reduce the dimension of optimization ***,the proposed algorithm and other two optimization algorithms which prevail in fan optimizations were compared by using test *** the same number of objective function evaluations,the proposed algorithm shows a fast convergency rate on finding the optimal objective function ***,this algorithm was used to optimize the rotor and stator blades of a large axial fan,with the efficiencies as the objectives at three flow rates,the high,the design and the low flow ***-two variables were included in the optimization *** results show that compared with the prototype fan,the total pressure efficiencies of the optimized fan at the high,the design and the low flow rate were increased by 3.35%,3.07%and 2.89%,respectively,after CFD simulations for 500 fan candidates with the constraint for the design *** optimization results validate the effectiveness and feasibility of the proposed algorithm.

关键词： multi-objective optimization surrogate-assisted evolutionary algorithm axial fan computational fluid dynamics aerodynamic optimization

Flood Duration Estimation Based on Multisensor,Multitemporal Remote Sensing:The Sardoba Reservoir Flood

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Journal of Earth Science 2023年第3期34卷 868-878页

作者： Limei Wang Guowang jin Xin xiong Institute of Geospatial Information Information Engineering UniversityZhengzhou 450001China

Single-sensor monitoring of flood events at high spatial and temporal resolutions is difficult because of the lack of data owing to instrument defects,cloud contamination,imaging ***,combining multisensor data provides an impressive solution to this *** this study,11 synthetic aperture radar(SAR)images and 13 optical images were collected from the Google Earth Engine(GEE)platform during the Sardoba Reservoir flood event to constitute a time series ***-based and indices-based methods were used for SAR and optical data,respectively,to extract the water *** final sequential flood water maps were obtained by fusing the results from multisensor time series *** show that,when compare with the Global Surface Water Dynamic(GSWD)dataset,the overall accuracy and Kappa coefficient of the water body extent extracted by our methods range from 98.8%to 99.1%and 0.839 to 0.900,*** flooded extent and area increased sharply to a maximum between May 1 and May 4,and then experienced a sustained decline over *** flood lasted for more than a month in the lowland areas in the north,indicating that the northern region is severely *** cover changes could be detected using the temporal spectrum analysis,which indicated that detailed temporal information benefiting from the multisensor data is highly important for time series analyses.

关键词： multitemporal flood monitoring SAR-optical data integration flood area assessment remote sensing flood control

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Understanding hydraulic fracture propagation behavior in tight sandstone–coal interbedded formations: an experimentalinvestigation

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Petroleum Science 2019年第1期16卷 148-160页

作者： Peng Tan Yan jin Liang Yuan Zhen-Yu xiong Bing hou Mian Chen Li-Ming Wan State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum CNPC Engineering Technology R&D Company Limited SINOPEC Shanghai O shore Oil & Gas Company

Whether hydraulic fractures could connect multiple gas zones in the vertical plane is the key to fracturing treatment to jointly exploit coalbed methane and tight sandstone gas through integrative hydraulic fracturing in tight sandstone–coal interbedded formations. Laboratory true triaxial hydraulic fracturing experiments were conducted on layered specimens with di erent combination types of natural sandstone and coal to simulate the propagation behavior of hydraulic fractures. The effects of the fracture initiation position, fracturing fluid viscosity and injection rate were discussed. The results showed that di erent fracture morphologies could be found. When initiating from coal seams, three patterns of fracture initiation and propagation were obtained:(1) The main hydraulic fracture initiated and propagated along the natural fractures and then diverged due to the effects of in situ stress and formed secondary fractures.(2) The hydraulic fracture initiated and propagated in the direction of the maximum horizontal stress.(3) Multiple fractures initiated and propagated at the same time. With the same fracturing fluid viscosity and injection rate, the hydraulic fractures initiating in sandstones had greater chances than those in coal seams to penetrate interfaces and enter neighboring layers. Excessively small or large fracturing fluid viscosity and injection rate would do harm to the vertical extension height of the induced fracture and improvement of the stimulated reservoir volume. Compared with operation parameters(fracturing fluid viscosity and injection rate), the natural weak planes in coals were considered to be the key factor that a ected the fracture propagation path. The experimental results would make some contributions to the development of tight sandstone–coal interbedded reservoirs.

关键词： Hydraulic fracturing Fracture propagation Sandstone-coal interbed Layered formation

Robust Identification of Road Surface Condition Based on Ego‑Vehicle Trajectory Reckoning

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Automotive Innovation 2022年第4期5卷 376-387页

作者： Cheng Tian Bo Leng Xinchen hou Yuyao Huang Wenrui Zhao Da jin Lu xiong Junqiao Zhao School of Automotive Studies Tongji UniversityShanghaiChina College of Electronic and Information Engineering Tongji UniversityShanghaiChina

The type of road surface condition(RSC)will directly affect the driving performance of *** the type of RSC is essential for both transportation agencies and individual ***,most existing methods are solely based on a dynamics-based method or an image-based method,which is susceptible to road excitation limitations and interference from the external ***,this paper proposes a decision-level fusion identification framework of the RSC based on ego-vehicle trajectory reckoning to accurately obtain the type of RSC that the front wheels of the vehicle will ***,a road feature extraction model based on multi-task learning is conducted,which can simultaneously segment the drivable area and road cast ***,the optimized candidate regions of interest are classified with confidence levels by *** environmental interference,candidate regions of interest regarded as virtual sensors are fused by improved Dempster-Shafer evidence theory to obtain the fusion ***,the ego-vehicle trajectory reckoning module based on the kinematic bicycle model is added to the proposed fusion method to extract the RSC experienced by the front *** performance of the entire framework is verified on a specific dataset with shadow and split curve *** results reveal that the proposed method can identify the RSC with accurate predictions in real time.

关键词： Road surface identification Ego-Vehicle trajectory reckoning Multi-task learning Dempster-Shafer evidence theory Autonomous vehicle