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Improving constraint onΩ_(m)from SDSS using marked correlation functions

Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 207-224页

作者： Limin Lai Jiacheng Ding Xiaolin Luo yizhao yang Zihan Wang Keshi Liu Guanfu Liu Xin Wang Yi Zheng Zhaoyu Li Le Zhang Xiao-Dong Li School of Physics and Astronomy Sun Yat-sen University Zhuhai CampusZhuhai 519082China Department of Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Department of Astronomy Tsinghua UniversityBeijing 100084China CSST Science Center for the Guangdong-Hong Kong-Macao Greater Bay Area SYSUZhuhai 519082China Peng Cheng Laboratory Shenzhen 518000China

Large-scale structure(LSS)surveys will increasingly provide stringent constraints on our cosmological ***,the density-marked correlation function(MCF)has been introduced,offering an easily computable density-correlation *** have demonstrated that MCFs offer additional,independent constraints on cosmological models beyond the standard two-point correlation(2PCF).In this study,we apply MCFs for the first time to SDSS CMASS data,aiming to investigate the statistical information regarding clustering and anisotropy properties in the Universe and assess the performance of various weighting schemes in MCFs,and finally obtain constraints onΩ_(m).Upon analyzing the CMASS data,we observe that,by combining different weights(α=[-0.2,0,0.2,0.6]),the MCFs provide a tight and independent constraint on the cosmological parameterΩ_(m),yieldingΩ_(m)=0.293±0.006 at the 1σlevel,which represents a significant reduction in the statistical error by a factor of 3.4 compared to that from *** constraint is consistent with recent findings from the small-scale clustering of BOSS galaxies(Zhai et ***.J.948,99(2023))within the 1σ***,we also find that our estimate is lower than the Planck measurements by about 2.6σ,indicating the potential presence of new physics beyond the standard cosmological model if all the systematics are fully *** method outlined in this study can be extended to other surveys and datasets,allowing for the constraint of other cosmological ***,it serves as a valuable tool for forthcoming emulator analysis on the Chinese Space Station Telescope(CSST).

关键词： large scale structure of universe dark energy cosmological parameters marked weighted correlation function

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砂岩作混合材生产复合硅酸盐水泥研究

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水泥技术 2024年第2期 87-90页

作者：朱兵兵梁进黄凯杨屹朝葛洲坝荆门水泥有限公司湖北荆门448000 中国葛洲坝集团水泥有限公司湖北武汉430070

分析了湖北荆门地区砂岩的化学成分、亚甲基蓝值及矿物组成,以砂岩作为混合材试验制备复合硅酸盐水泥,分析了不同种类及不同掺量砂岩对水泥标准稠度、凝结时间及力学强度的影响,验证了砂岩作混合材生产复合硅酸盐水泥的可行性。在以砂... 详细信息

分析了湖北荆门地区砂岩的化学成分、亚甲基蓝值及矿物组成,以砂岩作为混合材试验制备复合硅酸盐水泥,分析了不同种类及不同掺量砂岩对水泥标准稠度、凝结时间及力学强度的影响,验证了砂岩作混合材生产复合硅酸盐水泥的可行性。在以砂岩作混合材生产复合硅酸盐水泥时,需选取适合类别的砂岩,同时严格控制砂岩掺量,当砂岩掺量达到3%~4%时,将难以满足工程施工要求。

关键词：砂岩混合材复合硅酸盐水泥水泥适应性

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PCA-LSTM:An Impulsive Ground-Shaking Identification Method Based on Combined Deep Learning

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 3029-3045页

作者： yizhao Wang College of Pipeline and Civil Engineering China University of PetroleumQingdao266580China

Near-fault impulsive ground-shaking is highly destructive to engineering structures,so its accurate identification ground-shaking is a top priority in the engineering ***,due to the lack of a comprehensive consideration of the ground-shaking characteristics in traditional methods,the generalization and accuracy of the identification process are *** address these problems,an impulsive ground-shaking identification method combined with deep learning named PCA-LSTM is ***,ground-shaking characteristics were analyzed and groundshaking the data was annotated using Baker’***,the Principal Component Analysis(PCA)method was used to extract the most relevant features related to impulsive ***,a Long Short-Term Memory network(LSTM)was constructed,and the extracted features were used as the input for ***,the identification results for the Artificial Neural Network(ANN),Convolutional Neural Network(CNN),LSTM,and PCA-LSTMmodels were compared and *** experimental results showed that the proposed method improved the accuracy of pulsed ground-shaking identification by>8.358%and identification speed by>26.168%,compared to other benchmark models ground-shaking.

关键词： Impulsive ground-shaking principal component analysis artificial intelligence deep learning impulse recognition

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Recent process in developing advanced heterogeneous diatomic-site metal catalysts for electrochemical CO_(2)reduction

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Chinese Chemical Letters 2024年第7期35卷 4-13页

作者： Xueyang Zhao Bangwei Deng Hongtao Xie yizhao Li Qingqing Ye Fan Dong yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 611731China Suzhou Industrial Technology Research Institute of Zhejiang University Zhejiang UniversitySuzhou 215159China

Diatomic-site catalysts(DASCs)have emerged as a kind of promising heterogeneous candidate catalysts for electrochemical CO_(2)reduction(ECR),which is considered to retain the advantage of single-atom catalysts(SACs)but also introduce opportunities to exceed the limit of single-atom *** the past few years,tremendous progress has been achieved in this ***,the recent progress in ECR on DASCs has been *** will start with the classification of *** the challenges in the precise fabrication and characterization of DASCs have been *** introducing the advanced ECR performance on DASCs,superior to that on SACs,the synergistic effects of the dual metal atoms are highlighted,as this origin of the advanced ECR performance on DASCs is comprehensively ***,the major challenges and perspectives of DASCs have been proposed to shed light on the development of DASCs for ECR application.

关键词： Diatomic-site metal catalyst Electrochemical CO_(2)reduction Classification CO_(2)activation Synergistic effects

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Online battery model parameters identification approach based on bias-compensated forgetting factor recursive least squares

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Green Energy and Intelligent Transportation 2024年第4期3卷 12-22页

作者： Dong Zhen Jiahao Liu Shuqin Ma Jingyu Zhu Jinzhen Kong yizhao Gao Guojin Feng Fengshou Gu School of Mechanical Engineering Hebei University of TechnologyTianjin300401 China Advanced Equipment Research Institute Co. Ltd.of HEBUTTianjin300401 China College of Information Science and Engineering Hohai UniversityNanjing210098 China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai200240 China School of Computing and Engineering University of HuddersfieldHuddersfield HD13DHUK

Accuracy of a lithium-ion battery model is pivotal in faithfully representing actual state of battery,thereby influencing safety of entire electric *** estimation of battery model parameters using key measured signals is ***,measured signals inevitably carry random noise due to complex real-world operating environments and sensor errors,potentially diminishing model estimation *** the challenge of accuracy reduction caused by noise,this paper introduces a Bias-Compensated Forgetting Factor Recursive Least Squares(BCFFRLS)***,a variational error model is crafted to estimate the average weighted variance of random ***,an augmentation matrix is devised to calculate the bias term using augmented and extended parameter vectors,compensating for bias in the parameter *** assess the proposed method's effectiveness in improving parameter identification accuracy,lithium-ion battery experiments were conducted in three test conditions—Urban Dynamometer Driving Schedule(UDDS),Dynamic Stress Test(DST),and Hybrid Pulse Power Characterization(HPPC).The proposed method,alongside two contrasting methods—the offline identification method and Forgetting Factor Recursive Least Squares(FFRLS)—was employed for battery model parameter *** analysis reveals substantial improvements,with the mean absolute error reduced by 25%,28%,and 15%,and the root mean square error reduced by 25.1%,42.7%,and 15.9%in UDDS,HPPC,and DST operating conditions,respectively,when compared to the FFRLS method.

关键词： Lithium-ion battery Battery model Recursive least squares Parameter identification

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Evaluation of the Shallow Gas Hydrate Production Based on the Radial Drilling-Heat Injection-Back Fill Method

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Journal of Ocean University of China 2024年第1期23卷 119-128页

作者： CHEN Qiang WAN yizhao WU Nengyou SUN Jianye WANG Jian LIU Changling LI Yanlong LI Chengfeng HU Gaowei Key Laboratory of Gas Hydrate Ministry of Natural ResourcesQingdao 266071China Laboratory for Marine Mineral Resources Laoshan LaboratoryQingdao 266071China CNPC Offshore Engineering Company Limited Beijing 100028China Technology Innovation Center for Marine Methane Monitoring Ministry of Natural ResourcesQingdao 266071China

It has been evidenced that shallow gas hydrate resources are abundant in deep oceans *** geological back-ground,occurrence,and other characteristics differ significantly from deep-seated *** of the high risk of well construction and low production efficiency,they are difficult to be recovered by using conventional oil production *** a result,this paper proposes an alternative design based on a combination of radial drilling,heat injection,and backfilling ***-branch holes are used to penetrate shallow gas hydrate reservoirs to expand the depressurization area,and heat injection is utilized as a supplement to improve gas *** information collected from an investigation site close to the offshore production well in the South China Sea is used to assess the essential components of this plan,including well construction stability and gas production *** demonstrates that the hydraulic fracturing of the 60mbsf overburden layer can be prevented by regulating the drilling fluid ***,the traditional well structure is unstable,and the suction anchor is advised for better mechanical *** gas produc-tion rate can be significantly increased by combining hot water injection and depressurization ***,the suitable produc-tion equipment already in use is discussed.

关键词： shallow gas hydrate trail production radial drilling-heat injection-back fill method experimental and numerical simulation

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人居环境演变研究进展

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地理科学进展 2013年第5期32卷 710-721页

作者：张文忠谌丽杨翌朝中国科学院地理科学与资源研究所北京100101 中国科学院大学北京100049 美国俄勒冈大学规划与公共管理系尤金97403

人居环境作为人类栖息地,随着人类活动影响范围和强度的增加,人居环境问题越来越突出,人居环境演变过程也成为学术界关注的热点。本文梳理了近20年来关于人居环境演变的相关研究理论与方法,从人居环境演变趋势的影响因素分析、演变机制... 详细信息

人居环境作为人类栖息地,随着人类活动影响范围和强度的增加,人居环境问题越来越突出,人居环境演变过程也成为学术界关注的热点。本文梳理了近20年来关于人居环境演变的相关研究理论与方法,从人居环境演变趋势的影响因素分析、演变机制探析和研究方法等方面评述了国内外的研究动向。总体而言,人居环境研究呈现出多学科交叉、集成研究的特点,在数据获取、演变过程的研究上更多地采用了现代化技术和模拟分析方法,但学术界对人居环境的内涵、演变机制解析等仍然存在着分歧。与国外研究相比,中国人居环境研究起步较晚,研究内容限于人居环境评价,对人居环境演变机理涉及较少,且研究数据和方法较为单一。最后本文对未来研究进行了展望。

关键词：人居环境演变研究进展

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美国波特兰的宜居城市建设经验及启示

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国际城市规划 2016年第5期31卷 20-25页

作者：魏德辉谌丽杨翌朝美国俄勒冈大学城市规划与公共管理系北京联合大学应用文理学院城市科学系

本文深入剖析美国"精明增长"先锋城市——波特兰的城市规划建设经验,为我国遏制城市蔓延问题和建设宜居城市提供借鉴。在精明增长理念下,波特兰制定了严格的城市增长边界来控制城市向外蔓延,同时在城市增长边界内提高建筑密度,并采取增... 详细信息

本文深入剖析美国"精明增长"先锋城市——波特兰的城市规划建设经验,为我国遏制城市蔓延问题和建设宜居城市提供借鉴。在精明增长理念下,波特兰制定了严格的城市增长边界来控制城市向外蔓延,同时在城市增长边界内提高建筑密度,并采取增加绿色环境和公共空间、大力推行公交和慢行系统、提高服务设施可达性等措施来缓解高密度带来的负面影响,城市规划具有系统性和综合性。这些措施之所以能够实施,得益于波特兰上下结合的规划制度体系。法律赋予波特兰都会区政府合法和坚实的执行权力,借助州、区域、地方自上而下的规划体系,同时获益于城市自下而上的公共参与和监督的传统。此外,波特兰还十分注重在规划中引入地理信息系统等先进技术。最后,本文探讨了波特兰的城市规划经验对中国宜居城市建设的借鉴和启示。

关键词：宜居城市精明增长城市增长边界波特兰经验启示

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Vibration properties of Paulownia wood for Ruan sound quality using machine learning methods

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Journal of Forestry Research 2024年第5期35卷 216-222页

作者： yang yang College of Art and Design Harbin UniversityHarbin 150076People’s Republic of China College of Mechanical and Electrical Engineering Northeast Forestry UniversityHarbin 150040People’s Republic of China

As an important material for manufacturing resonant components of musical instruments,Paulownia has an important influence on the sound quality of *** this paper,a model for evaluating the sound quality of Ruan based on the vibration characteristics of wood is developed using machine learning ***,the selection of materials for Ruan manufacturing relies primarily on manually weighing,observing,striking,and listening by the instrument *** in scientific theory have hindered the quality of the finished *** this study,nine Ruans were manufactured,and a prediction model of Ruan sound quality was proposed based on the raw material information of *** of a total of 180 data sets,145 and 45 sets were chosen for training and validation,*** this paper,typical correlation analysis was used to determine the correlation between two single indicators in two adjacent pairwise combinations of the measured objects in each stage of the production process in *** vibra-tion characteristics of the wood were tested,and a model for predicting the evaluation of Ruan’s acoustic qualities was developed by measuring the vibration characteristics of the resonating plate *** acoustic quality of the Ruan sound board wood was evaluated and predicted using machine learning model generalized regression neural *** results show that the prediction of Ruan sound quality can be achieved using Matlab simulation based on the vibration characteristics of the soundboard *** the model-predicted values were compared with the tradi-tional predicted results,it was found that the generalized regression neural network had good performance,achieving an accuracy of 93.8%which was highly consistent with the experimental *** was concluded that the model can accurately predict the acoustic quality of the Ruan based on the vibration performance of the soundboards.

关键词： Sound quality Wood vibration performance Paulownia wood Machine learning methods

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Overview of radar detection methods for low altitude targets in marine environments

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Journal of Systems Engineering and Electronics 2024年第1期35卷 1-13页

作者： yang Yong yang Boyu School of Electronic Science National University of Defense TechnologyChangsha 410073China

In this paper,a comprehensive overview of radar detection methods for low-altitude targets in maritime environments is presented,focusing on the challenges posed by sea clutter and multipath *** performance of the radar detection methods under sea clutter,multipath,and combined conditions is categorized and summarized,and future research directions are outlined to enhance radar detection performance for low-altitude targets in maritime environments.

关键词： radar sea clutter multipath scattering detection low altitude target

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