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Compound Product of Hypermatrices

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Journal of Systems Science & Complexity 2024年第1期37卷 169-183页

作者： CHENG Daizhan meng Min zhang Xiao JI Zhengping Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China Department of Control Science and Engineering School of Electronics and Information EngineeringTongji UniversityShanghai 201210China National Center for Mathematics and Interdisciplinary Sciences Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100149China.

The semi-tensor product(STP)of matrices is generalized to multidimensional arrays,called the compound product of hypermatrices.The product is first defined for three-dimensional hypermatrices with compatible orders and then extended to general cases.Three different types of hyperdeterminants are introduced and certain properties are revealed.The Lie groups and Lie algebras corresponding to the hypermatrix products are constructed.Finally,these results are applied to dynamical systems.

关键词： Compound semi-tensor product hyperdeterminants hypereigenvalues and hypereigenvectors hypergeneral linear groups hypermatrices.

A LiDAR Point Clouds Dataset of Ships in a Maritime Environment

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1681-1694页

作者： Qiuyu zhang Lipeng Wang Hao meng Wen zhang Genghua Huang the College of Intelligent Systems Science and Engineering Harbin Engineering UniversityHarbin 150001China Key Laboratory of Space Active Opto-Electronics Technology Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083China

For the first time, this article introduces a LiDAR Point Clouds Dataset of Ships composed of both collected and simulated data to address the scarcity of LiDAR data in maritime applications. The collected data are acquired using specialized maritime LiDAR sensors in both inland waterways and wide-open ocean environments. The simulated data is generated by placing a ship in the LiDAR coordinate system and scanning it with a redeveloped Blensor that emulates the operation of a LiDAR sensor equipped with various laser beams. Furthermore,we also render point clouds for foggy and rainy weather conditions. To describe a realistic shipping environment, a dynamic tail wave is modeled by iterating the wave elevation of each point in a time series. Finally, networks serving small objects are migrated to ship applications by feeding our dataset. The positive effect of simulated data is described in object detection experiments, and the negative impact of tail waves as noise is verified in single-object tracking experiments. The Dataset is available at https://***/zqy411470859/ship_dataset.

关键词： 3D point clouds dataset dynamic tail wave fog simulation rainy simulation simulated data

Maximizing Submodular+Supermodular Functions Subject to a Fairness Constraint

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Tsinghua Science and Technology 2024年第1期29卷 46-55页

作者： Zhenning zhang Kaiqiao meng Donglei Du Yang Zhou Beijing Institute for Scientific and Engineering Computing Beijing University of TechnologyBeijing 100124China Faculty of Management University of New BrunswickFredericton E3B 5A3Canada School of Mathematics and Statistics Shandong Normal UniversityJinan 250014China

We investigate the problem of maximizing the sum of submodular and supermodular functions under a fairness constraint.This sum function is non-submodular in general.For an offline model,we introduce two approximation algorithms:A greedy algorithm and a threshold greedy algorithm.For a streaming model,we propose a one-pass streaming algorithm.We also analyze the approximation ratios of these algorithms,which all depend on the total curvature of the supermodular function.The total curvature is computable in polynomial time and widely utilized in the literature.

关键词： submodular function supermodular function fairness constraint greedy algorithm threshold greedy algorithm streaming algorithm

Optimizing circumferential assembly angle of rotor parts connected by curvic couplings based on acquired tooth surface error data

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Chinese Journal of Aeronautics 2024年第3期37卷 404-416页

作者： Huibin SUN meng LIU Yingzhi zhang Chenle WEI Key Laboratory of High Performance Manufacturing for Aero Engine Ministry of Industry and Information TechnologyNorthwestern Polytechnical UniversityXi’an 710072China AECC South Industry Company Limited Zhuzhou 412002China

Due to the excellent self-centering and load-carrying capability,curvic couplings have been widely used in advanced aero-engine rotors.However,curvic tooth surface errors lead to poor assembly precision.Traditional physical-master-gauge-based indirect tooth surface error measurement and circumferential assembly angle optimization methods have the disadvantages of high cost and weak generality.The unknown tooth surface fitting mechanism is a big barrier to assembly precision prediction and improvement.Therefore,this work puts forward a data-driven assembly simulation and optimization approach for aero-engine rotors connected by curvic couplings.The origin of curvic tooth surface error is deeply investigated.Using 5-axis sweep scan method,a large amount of high-precision curvic tooth surface data are acquired efficiently.Based on geometric models of parts,the fitting mechanism of curvic couplings is uncovered for assembly precision simulation and prediction.A circumferential assembly angle optimization model is developed to decrease axial and radial assembly runouts.Experimental results show that the assembly precision can be predicted accurately and improved dramatically.By uncovering the essential principle of the assembly precision formation and proposing circumferential assembly angle optimization model,this work is meaningful for assembly quality,efficiency and economy improvement of multistage aero-engine rotors connected by curvic couplings.

关键词： Curvic couplings Tooth surface error Assembly precision Axial and radial runouts Circumferential assembly angle

Insights into genetic diversity and phenotypic variations in domestic geese through comprehensive population and pan-genome analysis

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Journal of Animal Science and Biotechnology 2024年第1期15卷 88-107页

作者： Guangliang Gao Hongmei zhang Jiangping ni Xianzhi Zhao Keshan zhang Jian Wang Xiangdong Kong Qigui Wang Chongqing Academy of Animal Science Rongchang DistrictChongqing 402460China Livestock and Poultry Multi‑Omics Key Laboratory of Ministry of Agriculture and Rural Affairs College of Animal Science and TechnologySichuan Agricultural UniversityChengdu 611130China Chongqing Engineering Research Center of Goose Genetic Improvement Rongchang DistrictChongqing 402460China Department of Cardiovascular Ultrasound and Non‑Invasive Cardiology Sichuan Academy of Medical Sciences and Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengdu611731China Ultrasound in Cardiac Electrophysiology and Biomechanics Key Laboratory of Sichuan Province University of Electronic Science and Technology of ChinaChengdu611731China JiguangGene Biotechnology Co. Ltd.Nanjing210032China Jiangsu Agri-Animal Vocational College Taizhou225300China Poultry Science Institute Chongqing Academy of Animal ScienceNo.51 Changzhou AvenueRongchang DistrictChongqing 402460P.R.China

Background Domestic goose breeds are descended from either the Swan goose(Anser cygnoides)or the Greylag goose(Anser anser),exhibiting variations in body size,reproductive performance,egg production,feather color,and other phenotypic traits.Constructing a pan-genome facilitates a thorough identification of genetic variations,thereby deepening our comprehension of the molecular mechanisms underlying genetic diversity and phenotypic variability.Results To comprehensively facilitate population genomic and pan-genomic analyses in geese,we embarked on the task of 659 geese whole genome resequencing data and compiling a database of 155 RNA-seq samples.By constructing the pan-genome for geese,we generated non-reference contigs totaling 612 Mb,unveiling a collection of 2,813 novel genes and pinpointing 15,567 core genes,1,324 softcore genes,2,734 shell genes,and 878 cloud genes in goose genomes.Furthermore,we detected an 81.97 Mb genomic region showing signs of genome selection,encompassing the TGFBR2 gene correlated with variations in body weight among geese.Genome-wide association studies utilizing single nucleotide polymorphisms(SNPs)and presence-absence variation revealed significant genomic associations with various goose meat quality,reproductive,and body composition traits.For instance,a gene encoding the SVEP1 protein was linked to carcass oblique length,and a distinct gene-CDS haplotype of the SVEP1 gene exhibited an association with carcass oblique length.Notably,the pan-genome analysis revealed enrichment of variable genes in the“hair follicle maturation”Gene Ontology term,potentially linked to the selection of feather-related traits in geese.A gene presence-absence variation analysis suggested a reduced frequency of genes associated with“regulation of heart contraction”in domesticated geese compared to their wild counterparts.Our study provided novel insights into gene expression features and functions by integrating gene expression patterns across multiple organs and tissues in geese and analyzing population

关键词： Gene-CDS haplotype Goose GWAS Pan-genome Presence-absence variation Selection signal

Green manufacturing for achieving carbon neutrality goal requires innovative technologies:A bibliometric analysis from 1991 to 2022

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Journal of Environmental Sciences 2024年第6期140卷 255-269页

作者： Sheng zhang Xintian Wang Jiayu Xu Qinqin Chen meng Peng Jiming Hao School of Environment Tsinghua UniversityBeijing 100084China School of Environment&Natural Resources Renmin University of ChinaBeijing 100872China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China

Recent years have seen a significant increase in interest in green manufacturing as a key driver of global carbon-neutral efforts and sustainable development.To find the research hotspots of green manufacturing and reveal future research trends,this study reviewed and analyzed research articles from the Web of Science database on green manufacturing from1991 to 2022 using a bibliometric method.The findings indicate a significant rise in the number of articles related to green manufacturing since the 2010s.Moreover,there has been an increase in the involvement of scholars from developing countries such as China and India in this field.Based on the literature review and bibliometric cluster analysis on green manufacturing,we believed that future research may continue following the lines of intelligent technology integration,adoption of frontier engineering techniques,and industry development in line with carbon reduction targets.A framework for future green manufacturing development is proposed,with a focus on Chinese policies.The framework could provide policy implications for developing countries looking to pursue opportunities for development in green manufacturing.

关键词： Green manufacturing Carbon neutrality Sustainable development Innovative technologies China

Progress on Transition Metal Ions Dissolution Suppression Strategies in Prussian Blue Analogs for Aqueous Sodium-/Potassium-Ion Batteries

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Nano-Micro Letters 2024年第7期16卷 142-168页

作者： Wenli Shu Junxian Li Guangwan zhang Jiashen meng Xuanpeng Wang Liqiang Mai Department of Physical Science and Technology School of ScienceWuhan University of TechnologyWuhan 430070People’s Republic of China School of Materials Science and Engineering State Key Laboratory of Advanced Technology for Materials SynthesisWuhan University of TechnologyWuhan 430070People’s Republic of China Sanya Science and Education Innovation Park Wuhan University of TechnologySanya 572000People’s Republic of China Hubei Longzhong Laboratory Wuhan University of TechnologyXiangyang Demonstration ZoneXiangyang 441000People’s Republic of China

Aqueous sodium-ion batteries(ASIBs)and aqueous potassium-ion batteries(APIBs)present significant potential for large-scale energy storage due to their cost-effectiveness,safety,and environmental compatibility.Nonetheless,the intricate energy storage mechanisms in aqueous electrolytes place stringent require-ments on the host materials.Prussian blue analogs(PBAs),with their open three-dimensional framework and facile synthesis,stand out as leading candidates for aqueous energy storage.However,PBAs possess a swift capacity fade and limited cycle longevity,for their structural integrity is compromised by the pronounced dis-solution of transition metal(TM)ions in the aqueous milieu.This manuscript provides an exhaustive review of the recent advancements concerning PBAs in ASIBs and APIBs.The dissolution mechanisms of TM ions in PBAs,informed by their structural attributes and redox processes,are thoroughly examined.Moreover,this study delves into innovative design tactics to alleviate the dissolution issue of TM ions.In conclusion,the paper consolidates various strategies for suppressing the dissolution of TM ions in PBAs and posits avenues for prospective exploration of high-safety aqueous sodium-/potassium-ion batteries.

关键词： Prussian blue analogs Transition metal ions dissolution Suppression strategies Aqueous sodium-ion batteries Aqueous potassium-ion batteries

Visualization of MF/Diesel RCCI Combustion Process and Soot Emission

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Journal of Thermal Science 2024年第2期33卷 779-792页

作者： HUANG Chen ni Xiao GE Dameng LI Song zhang Wanzhi LIU Jinping zhang Tingting School of Mechanical and Electronic Engineering Shandong Agricultural UniversityTaian271018China Shandong Provincial Engineering Laboratory of Agricultural Equipment Intelligence Taian271018China Taian Technician Institute Taian271000China Sinotruk Taian Wuyue Special Vehicle Co. Ltd.Taian271000China School of Mechanical Engineering Shaanxi University of TechnologyHanzhong723001China School of Mechanical Engineering Anyang Institute of TechnologyAnyang455000China

Based on the optical engine,the ignition characteristics,combustion process and soot emission characteristics of diesel under different 2-Methylfuran(MF) atmospheres were investigated by high-speed photography and in-cylinder combustion analysis technology.The results show that at the same main injection timing,the ignition time of reactivity controlled compression ignition(RCCI) combustion mode is earlier than pure diesel combustion,and the ignition point is concentrated near the nozzle.Diesel acts as a spark plug to ignite the mixture,but the flame develops slowly in the early stages and the pressure in the cylinder rises slowly.Compared with pure diesel,RCCI combustion model has smaller peak values of in-cylinder pressure and heat release rate,shorter ignition delay period,earlier combustion phase and shorter combustion duration.At main spray time at 6℃A BTDC and 12℃A BTDC,with the increase of MF premixing ratio from 0 to 0.75,the peak cylinder pressure decreased by 19.6% and 26% respectively.In addition,with the increase of the MF heat value ratio,the area of KL factor> 1.5 in the combustion chamber decreased and the space integral natural luminescence(SINL) peak value decreased by 48.37%,and the soot formation rate and yield decreased significantly.However,when the MF heat value ratio was too large(75% of the total calorific value),the ignition delay period increased,and misfire occurred at the main injection timing of 0℃A BTDC.The RCCI mode of MF/diesel dual fuel has better stability,and better control effect can be obtained at different main inj ection timing.

关键词： 2-methylfuran RCCI visualization two-color method KL factor

Improving IEC thermal model for oil natural air natural transformers using optimised parameters based on dynamic simulation

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High Voltage 2024年第1期9卷 217-229页

作者： Lijing zhang Yingting Luo Gehao Sheng Zizhan ni Xiuchen Jiang Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghaiChina Electric Power Research Institute of Guangdong Power Grid Corporation GuangzhouChina

Accurate assessment of hot-spot temperature is essential for the safe operation of power transformers.Existing dynamic thermal models cannot estimate hot-spot temperature accurately since some input parameters are roughly determined by transformer capacity and cooling mode while ignoring the effect of winding structure,tank dimensions,and material physical properties.To improve the accuracy of temperature assessment,empirical parameters of the IEC thermal model including thermal constants,winding and oil exponents are optimised with the help of numerical simulation in this article.Based on energy conservation and heat transfer theory,a computational fluid dynamic(CFD)model of a transformer in oil natural air natural(ONAN)cooling mode is established.This CFD model simulates the entity's structure,sizes,and multi-stage heat dissipation processes realistically,so it can more precisely calculate the dynamic hot-spot temperature.According to the simulated temperature curves at different operating conditions,the thermal constants and oil exponent are estimated using non-linear regression,and the winding exponent is optimised using linear regression.A case study is conducted on an ONAN transformer.It shows the improved IEC model with optimised parameters can more accurately evaluate hot-spot temperature,and the absolute error is decreased by 2.4 K(38.7%)compared with traditional thermal models.

关键词： temperature properties. thermal