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Harnessing data using symbolic regression methods for discovering novel paradigms in physics

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 1-11页

作者： Jianyang guo Wan-Jian yin College of Energy Soochow Institute for Energy and Materials Innovations(SIEMIS)Jiangsu Provincial Key Laboratory for Advanced Carbon Materials and Wearable Energy TechnologiesSoochow UniversitySuzhou 215006China Shanghai Qi Zhi Institute Shanghai 200232China Light Industry Institute of Electrochemical Power Sources Soochow UniversitySuzhou 215006China

In recent years,machine-learning methods have profoundly impacted research in the interdisciplinary fields of ***,most machine-learning models lack interpretability,and physicists doubt the credibility of their conclusions because they cannot be combined with prior physical ***,this review focuses on symbolic regression,which is an interpretable machine-learning ***,the relevant concepts of machine learning are introduced in conjunction with ***,we provide an overview of symbolic regression ***,the recent directions for the application of symbolic regression methods in different subfields of physics are outlined,and an overview of the ways in which the applications of symbolic regression have evolved in the realm of physics is *** major aim of this review is to introduce the basic principles of symbolic regression and explain its applications in the field of physics.

关键词： machine learning genetic programming symbolic regression

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cKBET:assessing goodness of batch effect correction for single-cell RNA-seq

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Frontiers of Computer Science 2024年第1期18卷 215-228页

作者： Yameng ZHAO yin guo Limin LI School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an 710049China

Single-cell RNA sequencing reveals the gene structure and gene expression status of a single cell,which can reflect the heterogeneity between ***,batch effects caused by non-biological factors may hinder data integration and downstream *** the batch effect can be evaluated by visualizing the data,which actually is subjective and *** this work,we propose a quantitative method cKBET,which considers the batch and cell type information *** cKBET method accesses batch effects by comparing the global and local fraction of cells of different batches in different cell *** verify the performance of our cKBET method on simulated and real biological data *** experimental results show that our cKBET method is superior to existing methods in most *** general,our cKBET method can detect batch effect with either balanced or unbalanced cell types,and thus evaluate batch correction methods.

关键词： single-cell RNA-seq dataset b batch effect assessment cKBET method

A Dual-Task Learning Approach for Bearing Anomaly Detection and State Evaluation of Safe Region

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 229-241页

作者： Yuhua yin Zhiliang Liu Bin guo Mingjian Zuo School of Mechanical and Electrical Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Qingdao International Academician Park Research Institute Qingdao 266041China

Predictive maintenance has emerged as an effective tool for curbing maintenance costs,yet prevailing research predominantly concentrates on the abnormal *** the ostensibly stable healthy phase,the reliance on anomaly detection to preempt equipment malfunctions faces the challenge of sudden anomaly *** address this challenge,this paper proposes a dual-task learning approach for bearing anomaly detection and state evaluation of safe *** proposed method transforms the execution of the two tasks into an optimization issue of the hypersphere *** leveraging the monotonicity and distinguishability pertinent to the tasks as the foundation for optimization,it reconstructs the SVDD model to ensure equilibrium in the model’s performance across the two *** experiments verify the proposed method’s effectiveness,which is interpreted from the perspectives of parameter adjustment and enveloping *** the meantime,experimental results also show two deficiencies in anomaly detection accuracy and state evaluation *** theoretical analysis inspires us to focus on feature extraction and data collection to achieve *** proposed method lays the foundation for realizing predictive maintenance in a healthy stage by improving condition awareness in safe regions.

关键词： Bearing condition monitoring Anomaly detection Safe region Support vector data description

Long-term operation optimization of circulating cooling water systems under fouling conditions

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Chinese Journal of Chemical Engineering 2024年第1期65卷 255-267页

作者： Jiarui Liang yong Tian Shutong Yang yong Wang Ruiqi yin Yufei Wang School of Chemical Engineering and Environment China University of PetroleumBeijing102249China CHN Energy Xinjiang Chemical Co. LTDUrumqi830092China College of Mechanical and Transportation Engineering China University of PetroleumBeijing 102249China

Fouling caused by excess metal ions in hard water can negatively impact the performance of the circulating cooling water system(CCWS)by depositing ions on the heat exchanger's ***,the operation optimization of CCWS often prioritizes short-term flow velocity optimization for minimizing power consumption,without considering ***,low flow velocity promotes ***,it's crucial to balance fouling and energy/water conservation for optimal CCWS long-term *** study proposes a mixed-integer nonlinear programming(MINLP)model to achieve this *** model considers fouling in the pipeline,dynamic concentration cycle,and variable frequency drive to optimize the synergy between heat transfer,pressure drop,and *** optimizing the concentration cycle of the CCWS,water conservation and fouling control can be *** model can obtain the optimal operating parameters for different operation intervals,including the number of pumps,frequency,and valve local resistance *** experiments on cycle and environmental temperature reveal that as the cycle increases,the marginal benefits of energy/water conservation *** periods with minimal impact on fouling rate,energy/water conservation can be achieved by increasing the cycle while maintaining a low fouling ***,the proposed model has significant energy/water saving effects and can comprehensively optimize the CCWS through its incorporation of fouling and cycle optimization.

关键词： Computer simulation Circulating water system Fouling Concentration cycle Optimization Variable frequency drive

Broadband high-efficiency plasmonic metalens with negative dispersion characteristic

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Photonics Research 2024年第4期12卷 813-820页

作者： yong-QIANG LIU yong ZHU HONGCHENG yin JINHAI SUN YAN WANG yongXING CHE National Key Laboratory of Scattering and Radiation Beijing 100854China

Controlling the dispersion characteristic of metasurfaces(or metalenses) along a broad bandwidth is of great importance to develop high-performance broadband metadevices. Different from traditional lenses that rely on the material refractive index along the light trajectory, metasurfaces or metalenses provide a new regime of dispersion control via a sub-wavelength metastructure, which is known as negative chromatic ***, broadband metalenses design with high-performance focusing especially with a reduced device dimension is a significant challenge in society. Here, we design, fabricate, and demonstrate a broadband highperformance diffractive-type plasmonic metalens based on a circular split-ring resonator metasurface with a relative working bandwidth of 28.6%. The metalens thickness is only 0.09λ0(λ0is at the central wavelength),which is much thinner than previous broadband all-dielectric metalenses. The full-wave simulation results show that both high transmissive efficiency above 80%(the maximum is even above 90%) and high average focusing efficiency above 45%(the maximum is 56%) are achieved within the entire working bandwidth of 9–12 ***, an average high numerical aperture of 0.7(NA = 0.7) of high-efficiency microwave metalens is obtained in the simulations. The broadband high-performance metalens is also fabricated and experimental measurements verify its much higher average focusing efficiency of 55%(the maximum is above 65% within the broad bandwidth) and a moderate high NA of 0.6. The proposed plasmonic metalens can facilitate the development of wavelength-dependent broadband diffractive devices and is also meaningful to further studies on arbitrary dispersion control in diffractive optics based on plasmonic metasurfaces.

关键词： resonator dispersion high

Machine learning-based predictions of current and future susceptibility to retrogressive thaw slumps across the Northern Hemisphere

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Advances in Climate Change Research 2024年第2期15卷 253-264页

作者： Jing LUO guo-An yin Fu-Jun NIU Tian-Chun DONG Ze-yong GAO Ming-Hao LIU Fan YU State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China China Railway Qinghai-Tibet Group Co. LtdXining 810000China University of Chinese Academy of Sciences Beijing 100049China

Retrogressive thaw slumps(RTSs)caused by the thawing of ground ice on permafrost slopes have dramatically increased and become a common permafrost hazard across the Northern Hemisphere during previous ***,a gap remains in our comprehensive understanding of the spatial controlling factors,including the climate and terrain,that are conducive to these RTSs at a global *** machine learning methodologies,we mapped the current and future RTSs susceptibility distributions by incorporating a range of environmental factors and RTSs *** identified freezing-degree days and maximum summer rainfall as the primary environmental factors affecting RTSs *** final ensemble susceptibility map suggests that regions with high to very high susceptibility could constitute(11.6±0.78)%of the Northern Hemisphere's permafrost *** juxtaposed with the current(2000-2020)RTSs susceptibility map,the total area with high to very high susceptibility could witness an increase ranging from(31.7±0.65)%(SSP585)to(51.9±0.73)%(SSP126)by the *** insights gleaned from this study not only offer valuable implications for engineering applications across the Northern Hemisphere,but also provide a long-term insight into the potential change of RTSs in permafrost regions in response to climate change.

关键词： Retrogressive thaw slump Machine learning Susceptibility map Permafrost Northern Hemisphere

Quantum key distribution over a mimicked dynamic-scattering channel

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Science China(Information Sciences) 2024年第4期67卷 323-330页

作者： Qi-Hang LU Fang-Xiang WANG Wei CHEN Hai-Yang FU yin-Jie LU Shuang WANG De-yong HE Zhen-Qiang yin Guang-Can guo Zheng-Fu HAN CAS Key Laboratory of Quantum Information University of Science and Technology of China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of China Hefei National Laboratory University of Science and Technology of China

Free-space quantum key distribution(QKD) plays an important role in the global quantum network. However, free space channels suffer from the atmospheric turbulence and scattering effects of haze,fog, and dust, which significantly weaken the performance of QKD or even block the secure quantum ***, we prove the performance of QKD over a dynamic scattering channel can be enhanced significantly using a fast wavefront shaping technique. The system achieves on average 10-dB enhancement of quantum transmission efficiency and establishes a secure quantum link for QKD. Our work demonstrates the feasibility of QKD through free-space dynamic scattering channels and enhances the deployment capability of complex-channel QKD system.

关键词： quantum key distribution free space channel channel turbulence channel scattering wavefront shaping

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Atomically Substitutional Engineering of Transition Metal Dichalcogenide Layers for Enhancing Tailored Properties and Superior Applications

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Nano-Micro Letters 2024年第5期16卷 248-284页

作者： Zhaosu Liu Si yin Tee Guijian Guan Ming‑yong Han Institute of Molecular Plus Tianjin UniversityTianjin 300072People’s Republic of China Institute of Materials Research and Engineering A*STARSingapore 138634Singapore

Transition metal dichalcogenides(TMDs)are a promising class of layered materials in the post-graphene era,with extensive research attention due to their diverse alternative elements and fascinating semiconductor *** MX2 layers with different metal and/or chalcogen elements have similar structural parameters but varied optoelectronic properties,providing opportunities for atomically substitutional engineering via partial alteration of metal or/and chalcogenide atoms to produce ternary or quaternary *** resulting multinary TMD layers still maintain structural integrity and homogeneity while achieving tunable(opto)electronic properties across a full range of composition with arbitrary ratios of introduced metal or chalcogen to original counterparts(0–100%).Atomic substitution in TMD layers offers new adjustable degrees of freedom for tailoring crystal phase,band alignment/structure,carrier density,and surface reactive activity,enabling novel and promising *** review comprehensively elaborates on atomically substitutional engineering in TMD layers,including theoretical foundations,synthetic strategies,tailored properties,and superior *** emerging type of ternary TMDs,Janus TMDs,is presented specifically to highlight their typical compounds,fabrication methods,and potential ***,opportunities and challenges for further development of multinary TMDs are envisioned to expedite the evolution of this pivotal field.

关键词： Transition metal dichalcogenides Atomic substitution Tailored structure Tunable bandgap Enhanced applications

Environmental factors controlling soil warming and wetting during 2000-2020 in permafrost and non-permafrost regions across the Qinghai-Tibet Plateau

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Advances in Climate Change Research 2024年第2期15卷 285-296页

作者： guo-An yin Jing LUO Fu-Jun NIU Ming-Hao LIU Ze-yong GAO Tian-Chun DONG Wei-Heng NI State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China China Railway Qinghai-Tibet Group Co. Ltd.Xining 810000China University of Chinese Academy of Sciences Beijing 100049China

The Qinghai-Tibet Plateau(QTP)has experienced rapid environmental changes,including climate warming and wetting,since the *** environmental changes significantly impact the shallow soil hydrothermal conditions,which have key roles in land-atmosphere feedback and ecosystem ***,the spatial variations and responses of soil hydrothermal conditions to environmental changes over the QTP with permafrost(PF)and seasonal frost(SF)remain *** this study,we investigated the spatial variations in soil temperature(ST)and soil moisture(SM)changes over the QTP from 2000 to 2020 using 99 in-situ sites with observations at 4 depths(i.e.10,40,100 and 200 cm).The main environmental controlling factors were further identified using a calibrated statistical *** showed that significant(p<0.05)soil warming occurred at multiple soil layers during 2000-2020 with a wide variation(i.e.0.033-0.039℃ per year on average),whereas the warming rates at PF sites were two times greater than those at SF *** addition,the soil wetting rate was high over the SF region,whereas the soil wetting rate was low over the PF *** from air temperature,changes in thawing degree days and solar radiation(Srad)contributed most to soil warming in the PF region,whereas changes in rainfall,Srad and evaporation(EVA)have been identified as the key factors in the SF *** for soil wetting,changes in snowfall,freezing degree days and vegetation have noticeable nonlinear effects over the PF region,whereas changes in EVA,Srad and rainfall highlighted distinct linear and nonlinear effects in the SF *** findings enhance our understanding of the hydrothermal impacts of future environmental changes over the QTP.

关键词： Warming amd wetting Soil hydrothermal change Factor Permafrost Seasonal frost