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西南大学学报（自然科学版） 2007年第9期29卷 25-28页

作者：胡必锦雷鸣重庆交通大学理学院信息与计算科学系重庆400074

从Jensen不等式出发,设计了一个不同于Rao M等的证明残余寿命熵的有限性的方案,整个证明过程简明扼要.另外,考查了依赖一个单参数的分布类的残余寿命熵的有限性问题,并得到残余寿命熵关于参数的变化率可由Fisher信息控制的结果.

关键词：残余寿命熵有限性 Fisher信息

Chemico-biological conversion of carbon dioxide

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Journal of Energy Chemistry 2024年第2期89卷 371-387,I0009页

作者： Liangwei hu Junzhu Yang Qi Xia jin Zhang Hongxin Zhao Yuan Lu Zhejiang Province Key Laboratory of Plant Secondary Metabolism and Regulation College of Life Sciences and MedicineZhejiang Sci-Tech UniversityHangzhou 310018ZhejiangChina Key Laboratory of Industrial biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084China Department of Chemical Engineering Tsinghua UniversityBeijing 100084China College of biological and Chemical Engineering Jiaxing UniversityJiaxing 314000ZhejiangChina

The unabated carbon dioxide(CO_(2))emission into the atmosphere has exacerbated global climate change,resulting in extreme weather events,biodiversity loss,and an intensified greenhouse *** address these challenges and work toward carbon(C)neutrality and reduced CO_(2)emissions,the capture and utilization of CO_(2)have become imperative in both scientific research and *** cutting-edge approach to achieving efficient catalytic performance involves integrating green bioconversion and chemical *** innovative strategy offers several advantages,including environmental friendliness,high efficiency,and *** study provides a comprehensive review of existing technical routes for carbon sequestration(CS)and introduces two novel CS pathways:the electrochemicalbiological hybrid and artificial photosynthesis *** also thoroughly examines the synthesis of valuable Cnproducts from the two CS systems employing different catalysts and *** both systems heavily rely on electron transfer,direct and mediated electron transfer has been discussed and summarized in ***,this study explores the conditions suitable for different catalysts and assesses the strengths and weaknesses of *** also explored the biocompatibility of the electrode materials and developed novel *** materials were specifically engineered to combine with enzymes or microbial cells to solve the biocompatibility problem,while improving the electron transfer efficiency of ***,this review summarizes the relevant systems developed in recent years for manufacturing different products,along with their respective production efficiencies,providing a solid database for development in this *** novel chemical-biological combination proposed herein holds great promise for the future conversion of CO_(2)into advanced organic ***,it offers exciting prospects for utilizing CO_(2)in synthesizing

关键词： Carbon dioxide bioelectric synthesis Artificial photosynthesis Synthetic product

Assessment of International GNSS Service Global Ionosphere Map products over China region based on measurements from the Crustal Movement Observation Network of China

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Earth and Planetary Physics 2024年第2期8卷 400-407页

作者： jin hu Haibing Ruan FuQing huang ShengYang Gu XianKang Dou Institute of Space Weather Nanjing University of Information Science and TechnologyNanjing 210044China State Key Laboratory of Space Weather Chinese Academy of Sciences(CAS)Beijing 100190China School of Electronic Information Wuhan UniversityWuhan 430072China Wuxi Research Institute Nanjing University of Information Science and TechnologyWuxi Jiangsu 214000China CAS Key Laboratory of Geospace Environment School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China

The global ionosphere maps(GIM)provided by the International GNSS Service(IGS)are extensively utilized for ionospheric morphology monitoring,scientific research,and practical *** the credibility of GIM products in data-sparse regions is of paramount *** this study,measurements from the Crustal Movement Observation Network of China(CMONOC)are leveraged to evaluate the suitability of IGS-GIM products over China region in *** indices of mean error(ME),root mean square error(RMSE),and normalized RMSE(NRMSE)are then utilized to quantify the accuracy of IGS-GIM *** revealed distinct local time and latitudinal dependencies in IGS-GIM errors,with substantially high errors at nighttime(NRMSE:39%)and above 40°latitude(NRMSE:49%).Seasonal differences also emerged,with larger equinoctial deviations(NRMSE:33.5%)compared with summer(20%).A preliminary analysis implied that the irregular assimilation of sparse IGS observations,compounded by China’s distinct geomagnetic topology,may manifest as error *** results suggest that modeling based solely on IGS-GIM observations engenders inadequate representations across China and that a thorough examination would proffer the necessary foundation for advancing regional total electron content(TEC)constructions.

关键词： International GNSS Service(IGS)Global Ionosphere Maps(GIM) Crustal Movement Observation Network of China(CMONOC) total electron content(TEC) data assessment

Buried interface management via bifunctional NH_(4)BF_(4)towards efficient CsPbi_(2)Br solar cells with a V_(oc)over 1.4 V

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Journal of Energy Chemistry 2024年第2期89卷 364-370,I0009页

作者： Fazheng Qiu Ming-hua Li jinpeng Wu jin-Song hu School of Materials Science and Engineering NingboTech UniversityNingbo 315100ZhejiangChina Beijing National Laboratory for Molecular Sciences(BNLMS) Institute of ChemistryChinese Academy of SciencesBeijing 100190China College of Chemical Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China

CsPbi_(2)Br perovskite solar cells(PSCs)have drawn tremendous attention due to their suitable bandgap,excellent photothermal stability,and great potential as an ideal candidate for top cells in tandem solar ***,the abundant defects at the buried interface and perovskite layer induce severe charge recombination,resulting in the open-circuit voltage(V_(oc))output and stability much lower than ***,a novel buried interface management strategy is developed to regulate interfacial carrier dynamics and CsPbi_(2)Br defects by introducing ammonium tetrafluoroborate(NH_(4)BF_(4)),thereby resulting in both high CsPbi_(2)Br crystallization and minimized interfacial energy ***,NH_(4)^(+)ions could preferentially heal hydroxyl groups on the SnO_(2)surface and balance energy level alignment between SnO_(2)and CsPbi_(2)Br,enhancing charge transport efficiency,while BF_(4)^(-)anions as a quasi-halogen regulate crystal growth of CsPbi_(2)Br,thus reducing perovskite ***,it is proved that eliminating hydroxyl groups at the buried interface enhances the iodide migration activation energy of CsPbi_(2)Br for strengthening the phase *** a result,the optimized CsPbi_(2)Br PSCs realize a remarkable efficiency of 17.09%and an ultrahigh V_(oc)output of 1.43 V,which is one of the highest values for CsPbi_(2)Br PSCs.

关键词： Inorganic perovskite Buried interface Defect Stability Open-circuit voltage loss

Abnormal Action Recognition with Lightweight Pose Estimation Network in Electric Power Training Scene

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Computers, Materials & Continua 2024年第6期79卷 4979-4994页

作者： Yunfeng Cai Ran Qin jin Tang Long Zhang Xiaotian bi Qing Yang State Grid Jiangsu Electric Power Co. Ltd.Research InstituteNanjing211103China School of Computer Engineering Nanjing Institute of TechnologyNanjing211167China

Electric power training is essential for ensuring the safety and reliability of the *** this study,we introduce a novel Abnormal Action Recognition(AAR)system that utilizes a Lightweight Pose Estimation Network(LPEN)to efficiently and effectively detect abnormal fall-down and trespass incidents in electric power training *** LPEN network,comprising three stages—MobileNet,Initial Stage,and Refinement Stage—is employed to swiftly extract image features,detect human key points,and refine them for accurate ***,a Pose-aware Action Analysis Module(PAAM)captures the positional coordinates of human skeletal points in each ***,an Abnormal Action Inference Module(AAIM)evaluates whether abnormal fall-down or unauthorized trespass behavior is *** fall-down recognition,three criteria—falling speed,main angles of skeletal points,and the person’s bounding box—are *** identify unauthorized trespass,emphasis is placed on the position of the *** experiments validate the effectiveness and efficiency of the proposed system in ensuring the safety and reliability of electric power training.

关键词： Abnormal action recognition action recognition lightweight pose estimation electric power training

Hot Deformation Behavior and Microstructures Evolution of GNP-Reinforced Fine-Grained Mg Composites

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 407-424页

作者： Hengrui hu Jiayu Qin Yunpeng Zhu jinhui Wang Xiaoqiang Li Peipeng jin Qinghai Provincial Key Laboratory of New Light Alloys Qinghai UniversityXining 810016China Qinghai Provincial Engineering Research Center of High Performance Light Metal Alloys and Forming Qinghai UniversityXining 810016China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China School of Material Science and Engineering Lanzhou University of TechnologyLanzhou 730050China

Graphene nanoplates(GNPs)-reinforced magnesium matrix composites have been attracted great ***,knowledge is lack for the hot deformation behavior of GNP-reinforced magnesium(GNPs/Mg)*** this study,the fine-grained GNPs/Mg composite was fabricated by powder metallurgy process followed by *** hot deformation behavior,microstructure evolution and dynamic recrystallization(DRX)mechanism of fine-grained GNPs/Mg composite were investigated by hot compression test and electron back-scatter diffraction(EBSD).The hot compression tests of the composite were conducted at temperatures between 423 and 573 K with the strain rates from 0.001 to 1 s^(-1).The strain compensated power law equation was established to describe the hot deformation behavior of the *** stress exponent and activation energy of the composite are 7.76 and 83.23 kJ/mol,respectively,suggesting that the deformation mechanism is grain boundary slip controlled dislocation climb *** abnormally high stress exponent and activation energy are unattainable in the composite due to the fine grain size of the composites and the absence of Zener pinning and Orowan effects of GNPs *** grain size increases with the decrease in Zener-Hollomn(Z)parameter,which can be well fitted by power-law *** the increase in grain size and decrease in Z parameter,the geometrically necessary dislocation density decreases,which shows the approximately power-law relationship.A random and weak texture was formed after hot *** discontinuous dynamic recrystallization and continuous dynamic recrystallization mechanism dominated the DRX behavior at 473 K/0.001 s^(-1) and 573 K/0.001 s^(-1),respectively.

关键词： GNPs Mg composite Hot deformation behavior Constitutive equations Microstructure evolution Dynamic recrystallization

Effect of Low-Temperature Thermal Oxidation on the Capillary Performance of Sintered Copper Powder Wicks

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Journal of Thermal Science 2024年第1期33卷 29-40页

作者： Zhu Minghan FANG Runquan hu Yanxin ZHANG Jiangyun SHAO Dan huANG jin School of Material and Energy Guangdong University of TechnologyGuangzhou 510006China School of Electric Power Engineering Guangdong Polytechnic of Water Resources and Electric EngineeringGuangzhou 510006China Research into Artifacts Guangdong Key Laboratory of Battery SafetyGuangzhou Institute of Energy testingGuangzhou 511447China

In this study,a composite powder capillary wick is prepared,manufactured by sintering copper powder and surface treated by low-temperature thermal *** is used to improve the performance of the capillary *** forced flow method and infrared imaging method are used to test the permeability and capillary performance of the *** effects of different oxidation temperatures on the performance of capillary wick are *** experimental results show that the wetting performance of the oxidized samples is significantly *** the increase of oxidation temperature,the permeability *** capillary height and velocity of the thermally oxidized samples are significantly higher than those of the untreated capillary ***,the oxidation temperature needs to be adjusted to obtain the best capillary *** highest capillary performance is found at oxidation temperature of 300℃,with an increase of 46% compared to the untreated *** with other composite wicks show that the sample with an oxidation temperature of 300℃ has competitive capillary performance,making it a favorable alternative to two-phase heat transfer *** study shows that combining low-temperature thermal oxidation technology with powder sintering is a convenient and effective method to improve the capillary performance of powder wicks.

关键词： low-temperature thermal oxidation capillary performance copper powder permeability

A compact X-band backward traveling-wave accelerating structure

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Nuclear Science and Techniques 2024年第5期35卷 13-29页

作者： Xian-Cai Lin Hao Zha Jia-Ru Shi Qiang Gao Fang-Jun hu Qing-Zhu Li huai-bi Chen Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China

Very high-energy electrons(VHEEs)are potential candidates for FLASH radiotherapy for deep-seated *** proposed a compact VHEE facility based on an X-band high-gradient high-power *** this study,we investigated and realized the first X-band backward traveling-wave(BTW)accelerating structure as the buncher for a VHEE facility.A method for calculating the parameters of single cell from the field distribution was introduced to simplify the design of the BTW ***-domain circuit equations were applied to calculate the transient beam parameters of the buncher in the unsteady state.A prototype of the BTW structure with a thermionic cathode-diode electron gun was designed,fabricated,and tested at high power at the Tsinghua X-band high-power test *** structure successfully operated with 5-MW microwave pulses from the pulse compressor and outputted electron bunches with an energy of 8 MeV and a pulsed current of 108 mA.

关键词： Backward traveling-wave accelerating structure Equivalent circuit model High-power test Very high-energy electron radiotherapy

Disease Burden and Costs Associated with Multiple Sclerosis in China:A Cross-sectional Analysis of Nationwide Survey Data

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Neuroscience Bulletin 2024年第4期40卷 533-538页

作者： Yusheng Jia Xuanqi Qiao jin Zhao Hainan Li Shanlian hu Min hu Department of Health Economics School of Public HealthFudan UniversityShanghai200032China National Health Commission Key Laboratory of Health Technology Assessment Fudan UniversityShanghai200032China

DearEditors,Multiple sclerosis(MS)is a chronic,autoimmune neurological disorder characterized by inflammatory demyelination of the central nervous system;it is associated with reduced mobility,cognitive impairment,and numerous comorbidities[1].Global MS incidence(2.1 per 100,000 person-years)and prevalence(30.1 per 100,000)have increased in recent years,and its prevalence is notably higher in Western countries,ranging from~30 to 200 cases per 100,000[2].In China,recent epidemiological research has shown that the crude prevalence was 2.44 per 100,000 in 2016[3],and the age-and sex-adjusted incidence was 0.235 per 100,000 person-years[4].Despite the relatively low prevalence compared with the global average,China has extensively addressed the well-being of over 30,000 MS patients,enrolling MS in China's First National List of Rare Diseases in 2018.

关键词： prevalence impairment autoimmune

Research on Restoration of Murals Based on Diffusion Model and Transformer

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Computers, Materials & Continua 2024年第9期80卷 4433-4449页

作者： Yaoyao Wang Mansheng Xiao Yuqing hu jin Yan Zeyu Zhu School of Computing Hunan University of TechnologyZhuzhou412000China School of Computing Hunan Software Vocational and Technical UniversityXiangtan411100China

Due to the limitations of a priori knowledge and convolution operation,the existing image restoration techniques cannot be directly applied to the cultural relics mural restoration,in order to more accurately restore the original appearance of the cultural relics mural images,an image restoration based on the denoising diffusion probability model(Denoising Diffusion Probability Model(DDPM))and the Transformer *** process involves two steps:in the first step,the damaged mural image is firstly utilized as the condition to generate the noise image,using the time,condition and noise image patch as the inputs to the noise prediction network,capturing the global dependencies in the input sequence through the multi-attentionmechanismof the input sequence and feedforward neural network processing,and designing a long skip connection between the shallow and deep layers in the Transformer blocks between the shallow and deep layers using long skip connections to fuse the feature information of global and local outputs to maintain the overall consistency of the restoration results;In the second step,taking the noisy image as a condition to direct the diffusion model to back sample to generate the restored *** results show that the PSNR and SSIM of the proposedmethod are improved by 2%to 9%and 1%to 3.3%,respectively,which are compared to the comparison *** study proposed synthesizes the advantages of the diffusionmodel and deep learningmodel to make themural restoration results more accurate.

关键词： Transformer deep learning noise estimation network diffusion model mural restoration