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Thermodynamics and weak cosmic censorship conjecture of charged AdS black hole in the Rastall gravity with pressure

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Chinese Physics B 2020年第5期29卷 142-148页

作者： Xin-Yun hu Ke-Jian he Zhong-hua Li Guo-ping Li College of Economic and Management Chongqing Jiaotong UniversityChongqing 400074China Physics and Space College China West Normal UniversityNanchong 637000China

Treating the cosmological constant as a dynamical variable,we investigate the thermodynamics and weak cosmic censorship conjecture(WCCC)of a charged AdS black hole(BH)in the Rastall *** determine the energy momentum relation of charged fermion at the horizon of the BH using the Dirac *** on this relation,it is shown that the first law of thermodynamics still holds as a fermion is absorbed by the ***,the entropy of both the extremal and near-extremal BH decreases in the irreversible process,which means that the second law of thermodynamics is ***,we verify the validity of the WCCC by the minimum values of the metric function h(r)at its final *** the extremal charged AdS BH in the Rastall gravity,we find that the WCCC is always valid since the BH is *** for the case of near-extremal BH,we find that the WCCC could be violable in the extended phase space(EPS),depending on the value of the parameters of the BH and their variations.

关键词： Rastall gravity extended phase space black hole thermodynamics weak cosmic censorship conjecture

Low/distortion on Exterior Surface of Auto Body and Its Correction Method

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Chinese Journal of Mechanical Engineering 2012年第2期25卷 299-305页

作者： hu ping BAO Jingru ZHAO Kunmin School of Automotive Engineering Dalian University of TechnologyDalian 116024China

Surface low/distortion is one of the most challenging surface deflections that have a great effect on the exterior appearance of *** studies on surface distortion/deflection have focused on evaluation and visualization techniques,the research work on correction or prevention of surface low/distortion is limited,and there is no perfect surface low/distortion corrective method that can satisfy the needs of the engineering.A B-spline based geometry morphing algorithm is proposed and then a new program based on UG-NX platform is developed to modify the die face in the surface low/distortion *** verify this developed system,the experimental dies that can replicate the surface low/distortion phenomenon successfully is put to *** geometric variables are introduced to describe the basic geometry of typical depression features of automotive outer *** experimental dies are then designed to reflect various combinations of these geometric *** stamping experiments are conducted on cold rolled grade 5（CR5） sheet steel and various static measurements,such as oil-stoning,laser scanner,etc,are performed to measure and record the surface low/*** approaches including good bearing,holds in blank and die face morphing that aim to correct low/distortions are tried out and surface low/distortions are observed in the specimen with reverse draw depth of 10 *** measurement results show that die morphing is a practical and effective method to correct the surface low/*** correction method proposed can be used to minimize the occurrence of surface low/distortion in die manufacturing,which has certain reference significance to the correction of surface low/distortion.

关键词： sheet metal forming surface low/distortion surface deflection corrective method morphing algorithm

Assumed stress quasi-conforming triangular element for couple stress theory

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Acta Mechanica Solida Sinica 2017年第4期30卷 335-344页

作者： Changsheng Wang Xiangkui Zhang ping hu School of Automotive Engineering State Key Laboratory of Structural Analysis for Industrial EquipmentDalian University of Technology

In this paper, a 3-node triangular element for couple stress theory is proposed based on the assumed stress quasi-conforming method. The formulation starts from polynomial approx- imation of stresses. Then the stress-function matrix is treated as the weighted function to weaken the strain-displacement equations. Finally, the string-net functions are introduced to calculate strain integration and the stress smooth technique is adopted to improve the stress accuracy. Numerical results show that the proposed new model can pass the Co- 1 patch test with excellent precision, does not exhibit extra zero energy modes and can cap- ture the scale effects of microstructure.

关键词： Quasi-conforming Couple stress theory Fundamental analytical solutions

Reactive scheduling of multiple EOSs under cloud uncertainties:model and algorithms

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Journal of Systems Engineering and Electronics 2021年第1期32卷 163-177页

作者： WANG Jianjiang hu Xuejun he Chuan College of Systems Engineering National University of Defense TechnologyChangsha 410073China Business School Hunan UniversityChangsha 410082China Beijing Institute of Tracking and Telecommunications Technology Beijing 100094China

Most earth observation satellites(EOSs)are low-orbit satellites equipped with optical sensors that cannot see through ***,cloud coverage,high dynamics,and cloud uncertainties are important issues in the scheduling of *** proactive-reactive scheduling framework has been proven to be effective and efficient for the uncertain scheduling problem and has been extensively *** studies have been conducted on methods for the proactive scheduling of EOSs,including expectation,chance-constrained,and robust optimization models and the relevant solution *** study focuses on the reactive scheduling of EOSs under cloud ***,using an example,we describe the reactive scheduling problem in detail,clarifying its significance and key *** the two key objectives of observation profits and scheduling stability,we construct a multi-objective optimization mathematical ***,we obtain the possible disruptions of EOS scheduling during execution under cloud uncertainties,adopting an event-driven policy for the reactive *** the different disruptions,different reactive scheduling algorithms are ***,numerous simulation experiments are conducted to verify the feasibility and effectiveness of the proposed reactive scheduling *** experimental results show that the reactive scheduling algorithms can both improve observation profits and reduce system perturbations.

关键词： earth observation satellite(EOS) uncertainty of clouds reactive scheduling multi-objective optimization event-driven heuristic

Formation Tracking for Nonlinear Multi-agent Systems with Input and Output Quantization via Adaptive Output Feedback Control

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Journal of Systems Science & Complexity 2020年第2期33卷 401-425页

作者： hu Jinglin SUN Xiuxia he Lei Air Force Engineering University Xi'an 710038China System Engineering Research Institute Air Force Research InstituteBeijing 100070China

Signal quantization can reduce communication burden in multi-agent systems,whereas it brings control challenge to multi-agent formation *** paper studies the output feedback control problem for formation tracking of multi-agent systems with both quantized input and *** agents are described by a nonlinear dynamic model with unknown parameters and immeasurable *** estimate immeasurable states and solve the uncertainties,state observers are developed by using dynamic high-gain *** proper parameter designs,an output feedback quantized controller is established based on quantized output signals,and the quantization effect on the control system is *** analysis proves that,with the proposed control scheme,multi-agent systems can track the reference trajectory while forming and maintaining the desired formation *** addition,all the signals in the closed-loop systems are ***,the numerical simulation and practical experiment are provided to verify the theoretical analysis.

关键词： Adaptive output feedback formation tracking hysteretic quantizer multi-agent system

Allelic Variation at the TaZds-A1 Locus on Wheat Chromosome 2A and Development of a Functional Marker in Common Wheat

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Journal of Integrative Agriculture 2012年第7期11卷 1067-1074页

作者： DONG Chang-hai MA Zhi-ying XIA Xian-chun ZHANG Li-ping he Zhong-hu College of Agronomy Agricultural University ofHebei Baoding 071001 P.R.China Institute of Crop Sciences National Wheat Improvement Center~The National Key Facility for Crop Gene Resources and Genetic Improvement Chinese Academy of Agricultural Sciences (CAAS) Beijing 100081 P.R.China CIMMYT China Office/CAAS Beijing 100081 P.R.China Beijing Engineering and Technique Research Center of Hybrid Wheat Beijing Academy of Agricultural and Forestry Sciences Beijing 100097 P.R. China

ζ （zeta）-carotene desaturase （ZDS） is a key enzyme for carotenoid biosynthesis, demonstrating high association with the yellow pigment （YP） content in wheat grain. Cloning ZDS gene and developing functional markers are important for marker-assisted selection in wheat breeding. In the present study, the full-length DNA sequence of a ZDS gene on wheat chromosome 2A, designated TaZds-A1, was cloned, with 14 exons and 13 introns, and it has an open reading frame （ORF） of 1 707 bp, encoding 568 amino acid residues. A co-dominant functional marker, YP2A-1, was designed based on the polymorphisms of two alleles at the locus, TaZds-Ala and TaZds-Alb, yielding 183- and 179-bp fragments in TaZds-Ala and TaZds-Alb genotypes, respectively. A new QTL for YP content was detected on chromosome 2A, co-segregating with the functional marker YP2A-1 and TaZds-A1; it explained 11.3% of the phenotypic variance for YP content in a doubled haploid （DH） population from Zhongyou 9507/CA9632. Among 217 Chinese wheat cultivars and advanced lines, the average grain YP content of 126 cultivars with TaZds-Alb allele was 7.8% higher than that of 91 cultivars with TaZds- Ala allele.

关键词： Triticum aestivum functional marker QTL ζ-carotene desaturase ZDS

Reflectance calibration and shadow effect of VNIS spectra acquired by the Yutu rover

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Research in Astronomy and Astrophysics 2015年第9期15卷 1587-1596页

作者： Sen hu Yang-Ting Lin Bin Liu Wei Yang Zhi-ping he Wei-Fan Xing Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of Sciences Key Laboratory of Space Active Opto-Electronics Technology Shanghai Institute of Technical Physics Chinese Academy of Sciences China University of Geosciences

Yutu is the first lunar rover after the Apollo program and Luna missions. One of the payloads on the Yutu rover, the Visible and Near-infrared Imaging Spectrometer （VNIS）, has acquired four VIS/NIR images and SWIR spectra near its landing site in Mare Imbrium. The radiance images were reduced through repairing bad lines and bad points, and applying flat field correction, and then were converted into reflectance values based on the solar irradiance and angles of incidence. A significant shadow effect was observed in the VIS/NIR image. The shadowed regions show lower reflectance with a darkening trend compared with illuminated regions. The re- flectance increased by up to 24% for entire images and 17% for the VIS/NIR-SWlR overlapping regions after shadow correction. The correction for the shadow effect will remarkably decrease the estimate of FeO content, by up to 4.9 wt.% in this study. The derived FeO contents of CD-005-008 after shadow correction are around 18.0 wt.%.

关键词： Moon -- Chang'e-3 -- Yutu -- VNIS -- shadow -- reflectance

A Deep Generative Model with Multiscale Features Enabled Industrial Internet of Things for Intelligent Fault Diagnosis of Bearings

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Research 2023年第3期2023卷 57-68页

作者： he-xuan hu Yicheng Cai Qiang hu Ye Zhang Key Laboratory of Water Big Data Technology of Ministry of Water Resources Hohai UniversityNanjing 211100P.R.China College of Computer and Information Hohai UniversityNanjing 211100P.R.China

Effective condition monitoring and fault diagnosis of bearings can not only maximize the life of rolling bearings and prevent unexpected shutdowns caused by equipment failures but also eliminate unnecessary costs and waste caused by excessive ***,the existing deep-learning-based bearing fault diagnosis models have the following *** of all,these models have a large demand for fault ***,the previous models only consider that single-scale features are generally less effective in diagnosing bearing ***,we designed a bearing fault data collection platform based on the Industrial Internet of Things,which is used to collect bearing status data from sensors in real time and feed it back into the diagnostic *** the basis of this platform,we propose a bearing fault diagnosis model based on deep generative models with multiscale features(DGMMFs)to solve the above *** DGMMF model is a multiclassification model,which can directly output the abnormal type of the ***,the DGMMF model uses 4 different variational autoencoder models to augment the bearing data and integrates features of different *** with single-scale features,these multiscale features contain more information and can perform ***,we conducted a large number of related experiments on the real bearing fault datasets and verified the effectiveness of the DGMMF model using multiple evaluation *** DGMMF model has achieved the highest value under all metrics,among which the value of precision is 0.926,the value of recall is 0.924,the value of accuracy is 0.926,and the value of F1 score is 0.925.

关键词： fault bearings diagnosis

Effect of Polymer on Morphology and Structure of Calcium Silicate Hydrate Prepared via Precipitation Method

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Journal of Wuhan University of Technology(Materials Science) 2014年第3期29卷 504-506页

作者：吕林女 ping Bing 何永佳 he Liu WU Xi hu Shuguang School of Science Wuhan University of Technology State Key Laboratory of Silicate Materials for Architectures Wuhan University of Technology School of Materials Science and Engineering Wuhan University of Technology The 5th Engineering Ltd. of The 11th Engineering Bureau of China Railway

The effects of polyaerylamide （PAM） and polyvinyl alcohol （PVA） on morphology and structure of calcium silica~ hydrate with C/S 1.0-1.7 prepared via precipitation in solution were investigated by XRD, FT-IR and TEM techniques. The results show that incorporation of the polymers decreased the order degree, increased the interlayer spacing and disturbed the layered stacking of C-S-H. Interlayer spacing expansion depended on C/S ratios and type of polymer. Interlayer spacing expansion had a minimum at C/S 1.0 and a maximum at C/S 1.3 and 1.5. Interlayer spacing expansion of PAM was bigger than that of PVA with the same C/S. C-S-H added with PVA mainly exhibited foil-like and fibrillar morphology. The fibrils were of variable length from a few tens of nanometers to a few hundreds of nanometers. Fibrils or foils seemed to be longer in the presence of PVA.

关键词： C-S-H morphology structure polyacrylamide polyvinyl alcohol