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重力及其垂直梯度交叉约束联合密度结构反演方法

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地球物理学报 2022年第10期65卷 4111-4121页

作者：马国庆李欣蔚王泰涵熊盛青高桐吉林大学地球探测科学与技术学院长春130026 中国自然资源航空物探遥感中心北京100083

重力垂直梯度能突出浅部地质目标,具有较高的水平分辨率,而重力异常则可以更好地保留较深场源的信息,重力与重力梯度联合勘探常用来获取不同深度场源的异常特征.本文提出重力及其垂直梯度交叉约束联合密度结构反演方法,其采用交叉梯度... 详细信息

重力垂直梯度能突出浅部地质目标,具有较高的水平分辨率,而重力异常则可以更好地保留较深场源的信息,重力与重力梯度联合勘探常用来获取不同深度场源的异常特征.本文提出重力及其垂直梯度交叉约束联合密度结构反演方法,其采用交叉梯度实现重力与重力梯度数据联合反演,并将二者单独反演结果作为归一化权函数约束联合反演过程.该方法可有效改善不同参量反演结果集中于异常变化较大区域的缺点,提升不同深度场源的分辨率,更加准确地揭示深部场源的分布.模型试验结果表明该方法能清晰恢复不同深度场源的密度结构分布特征,且具有良好抗噪能力.针对辽源采空区勘查开展重力与其垂直梯度联合测量,利用本文数据联合反演圈定出了6个采空区,与以往已知矿点位置完全一致,且与高密度电阻率法解释结果吻合良好,为区域规划建设提供了准确的依据.此外,我们还对长白山火山地区卫星重力及其梯度数据进行反演,估计了岩浆囊的位置和范围,且与前人地球物理勘探结果较为吻合,进一步证明了本文方法的实用性.

关键词：重力及其垂直梯度高分辨率交叉约束权函数采空区岩浆囊

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Hole mobility enhancement in monolayer WSe2 p-type transistors through molecular doping

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Science China(Information Sciences) 2024年第6期67卷 207-213页

作者： Shiyuan LIU xiong xiong Xin WANG Xinhang SHI Ru HUANG Yanqing WU School of Integrated Circuits and Beijing Advanced Innovation Center for Integrated Circuits Peking University Wuhan National High Magnetic Field Center and School of Integrated Circuits Huazhong University of Science and Technology

Two-dimensional （2D） transition metal dichalcogenide （TMDC） semiconductor materials exhibit extraordinary electrical properties,holding promise for the realization of next-generation complementary metal-oxide-semiconductor （CMOS） devices at ultimate ***,constrained by effective device doping strategies,the hole mobility and device performance of tungsten diselenide （WSe2） p-type transistors,especially monolayer chemical vapor deposition （CVD）-grown WSe2,have not met *** this paper,an effective performance enhancement of monolayer WSe2p-type transistor was achieved through a molecular doping *** monolayer WSe2directly on SiO2back-gated substrates and leveraging energy band alignment design,4-nitrobenzenediazonium tetrafluoroborate （4-NBD） molecular dopant with a concentration of 10 m M was utilized to modulate the Fermi level position of monolayer WSe2for hole *** devices demonstrated a more than 98%increase in hole mobility,reaching up to 97 cm2·V-1·s-1while maintaining the current on/off ratio of *** p-type WSe2transistors with 1μm channel length exhibit a high drive current surpassing 176μA·μm-1,exceeding previous CVD-WSe2devices with similar channel *** straightforward and effective approach to improving the electrical performance of WSe2transistors paves the way for advanced logic technologies based on transition metal dichalcogenide semiconductors.

关键词： CVD-grown WSe$_2$ molecular doping 4-NBD p-type transistors hole mobility

A Generalized Blow up Criteria with One Component of Velocity for 3D Incompressible MHD System

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 253-264页

作者： Bin HAN Xi xiong Department of Mathematics Hangzhou Dianzi UniversityHangzhou 310018China

In this paper,the authors study the global regularity of the 3D magnetohydrodynamics system in terms of one velocity *** particular,they establish a new Prodi-Serrin type regularity criterion in the framework of weak ... 详细信息

关键词： MHD Regularity Blow-up criterion

利用CE1-GRS数据分析月表钾元素分布特征

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原子能科学技术 2013年第8期47卷 1417-1421页

作者：杨佳葛良全熊盛青张庆贤谷懿成都理工大学地学核技术四川省重点实验室四川成都610059 中国国土资源航空物探遥感中心北京100083

为从嫦娥一号伽马射线谱仪(CE1-GRS)探测数据获取月表K元素的分布特征,利用CE1-GRS 2C级数据,通过CE1-GRS数据处理的相关技术方法研究,得到K计数全月分布图的初步结果。该分布图反映出K含量高的区域主要集中在月球正面的西部月海区及附... 详细信息

为从嫦娥一号伽马射线谱仪(CE1-GRS)探测数据获取月表K元素的分布特征,利用CE1-GRS 2C级数据,通过CE1-GRS数据处理的相关技术方法研究,得到K计数全月分布图的初步结果。该分布图反映出K含量高的区域主要集中在月球正面的西部月海区及附近;而K含量次之的区域位于南极爱特肯盆地内。在月球背面,K含量普遍表现为低值特征。将CE1-GRS获取的K分布图与月球勘探者伽马射线谱仪(LP-GRS)数据的K全月分布图进行了比较分析,两者体现出的月表K分布主要特征基本一致。

关键词：月球探测伽马能谱嫦娥一号 K元素分布特征

A new gravitational theory and dark matter problem

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Communications in Theoretical Physics 2024年第6期76卷 129-136页

作者： xiong Zhao Yongge Ma Department of Physics Beijing Normal UniversityBeijing 100875China

We propose a new gravitational theory with torsion based on Riemann-Cartan geometry,in which all physical quantities are *** addition to the spacetime metric,the gravitational degrees of freedom in this theory also include the torsion and two scalar *** energy-momentum tensor of the matter fields in this theory is also proposed.A spherically symmetric static vacuum solution of the theory is *** turns out that this solution can fit the observational data of the rotation curve outside the stellar disk in the Milky ***,the galactic dark matter may just be the gravitational effect of the theory with torsion.

关键词： gravity torsion dark matter

Equivariant Chern Classes of Orientable Toric Origami Manifolds

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 221-234页

作者： Yueshan xiong Haozhi ZENG School of Mathematics and StatisticsHuazhong University of Science and Technology Wuhan 430074China

A toric origami manifold,introduced by Cannas da Silva,Guillemin and Pires,is a generalization of a toric symplectic *** a toric symplectic manifold,its equivariant Chern classes can be described in terms of the corresponding Delzant polytope and the stabilization of its tangent bundle splits as a direct sum of complex line *** in general a toric origami manifold is not simply connected,so the algebraic topology of a toric origami manifold is more difficult than a toric symplectic *** this paper they give an explicit formula of the equivariant Chern classes of an oriented toric origami manifold in terms of the corresponding origami ***,they prove the stabilization of the tangent bundle of an oriented toric origami manifold also splits as a direct sum of complex line bundles.

关键词： Equivariant Chern classes Toric origami manifolds Unitary structures Spin structures

Autonomous navigation method of satellite constellation based on adaptive forgetting factors

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Chinese Journal of Aeronautics 2024年第7期37卷 317-332页

作者： Dong WANG Jing YANG Kai xiong School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Science and Technology on Space Intelligent Control Laboratory Beijing Institute of Control EngineeringBeijing 100094China

To address the problem that model uncertainty and unknown time-varying system noise hinder the filtering accuracy of the autonomous navigation system of satellite constellation,an autonomous navigation method of satellite constellation based on the Unscented Kalman Filter with Adaptive Forgetting Factors(UKF-AFF)is *** process noise covariance matrix is estimated online with the strategy that combines covariance matching and adaptive adjustment of forgetting *** adaptive adjustment coefficient based on squared Mahalanobis distance of state residual is employed to achieve online regulation of forgetting factors,equipping this method with more *** intersatellite direction vector obtained from photographic observations is introduced to determine the constellation satellite orbit together with the distance measurement to avoid rank deficiency *** that the number of available measurements varies online with intersatellite visibility in practical applications such as time-varying constellation configurations,the smooth covariance matrix of state correction determined by innovation and gain is adopted and constructed *** analysis of the proposed method is also *** effectiveness of the proposed method is verified by the Monte Carlo simulation and comparison *** estimation accuracy of constellation position and velocity of UKF-AFF is improved by 30%and 44%respectively compared to those of the extended Kalman filter,and the method proposed is also better than other several adaptive filtering methods in the presence of significant model uncertainty.

关键词： Constellation autonomous navigation Unscented Kalman filter Adaptive forgetting factor Model uncertainty Stability analysis

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

A wide-linear-range and low-hysteresis resistive strain sensor made of double-threaded conductive yarn for human movement detection

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Journal of Materials Science & Technology 2024年第5期172卷 202-212页

作者： Fei Huang Jiyong Hu xiong Yan Shanghai Frontier Science Research Center for Modern Textiles Donghua UniversityShanghai 201620China

Yarn-based flexible strain sensors with advantages in wearability and integrability have attracted wide ***,it is still a big challenge to achieve yarn-based strain sensors with a wide linear strain range,low hysteresis,and durability synchronously that can be used for full range detection of human body ***,a new structure,double-threaded conductive yarn with rhythmic strain distribu-tion,is reported to markedly widen the linear strain range of microcrack-based stretchable strain sensors.A new method of winding and thermally adhering hot-melt filaments on the surface of the elastic fiber is used to achieve double-threaded yarn(DTY)with rhythmic strain *** proposed strategy,the integration of heterogeneous materials,is reported to significantly reduce the mechanical hysteresis of composite *** strain distribution of the DTY during stretching causes multi-level micro-cracks in different regions of the carbon nanotube(CNT)conductive layer deposited on the surface of the ***,the sensing performance of DTY-based strain sensor can be adjusted by designing the structural *** final prepared flexible strain sensor has the advantages of a wide linear strain range(100%),great sensitivity(GF=12.43),low hysteresis,rapid response(158 ms),high repeatability(>2000 cycles at 50%strain),and hydrophobicity,*** sensor can monitor human motion repeatedly and stably well,and shows great advantages in flexible wearable devices.

关键词： Double-threaded yarn Strain redistribution Hysteresis Human motion monitoring