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A survey on deep geometry learning:From a representation perspective

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Computational Visual Media 2020年第2期6卷 113-133页

作者： yun-peng xiao Yu-Kun Lai Fang-Lue Zhang Chunpeng Li Lin Gao Institute of Computing Technology Chinese Academy of SciencesBeijingChina School of Computer Science and Informatics Cardiff UniversityWalesUK School of Engineering and Computer Science Victoria University of WellingtonWellingtonNew Zealand

Researchers have achieved great success in dealing with 2 D images using deep *** recent years,3 D computer vision and geometry deep learning have gained ever more *** advanced techniques for 3 D shapes have been proposed for different *** 2 D images,which can be uniformly represented by a regular grid of pixels,3 D shapes have various representations,such as depth images,multi-view images,voxels,point clouds,meshes,implicit surfaces,*** performance achieved in different applications largely depends on the representation used,and there is no unique representation that works well for all ***,in this survey,we review recent developments in deep learning for 3 D geometry from a representation perspective,summarizing the advantages and disadvantages of different representations for different *** also present existing datasets in these representations and further discuss future research directions.

关键词： 3D shape representation geometry learning neural networks computer graphics

Petrography and origin of the Lower Ordovician microbial carbonates in the Songzi Area of Hubei Province,middle Yangtze region,China

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Petroleum Science 2019年第5期16卷 956-971页

作者： Chuan-Tao xiao Guo-Qi Wei Zhen-Yu Song yun-peng xiao Wei Yang Man Dong yun-Fei Huang Da Gao Geosciences School of Yangtze University Wuhan 430100HubeiChina Research Institute of Petroleum Exploration and Development PetroChinaLangfang 065007HebeiChina

This study is the first systematic assessment of the Lower Ordovician microbial carbonates in Songzi,Hubei Province,*** paper divides the microbial carbonates into two types according to growth patterns,namely nongranular and *** nongranular types include stromatolites,thrombolites,dendrolites,leiolites and laminites;the granular types are mainly oncolites and may include a small amount of microbiogenic *** to their geometric features,the stromatolites can be divided into four types:stratiform,wavy,columnar and ***,dipyramidal columnar stromatolites are identified for the first time and represent a new type of columnar *** thrombolites are divided into three types:speckled,reticulated and *** grazing gastropod Ecculiomphalus and traces of bioturbation are observed in the speckled and reticulated *** paper considers these two kinds of thrombolites to represent bioturbated *** findings not only fill gaps in the field of domestic Ordovician bioturbated thrombolites but also provide new information for the study of *** on the analysis of the sedimentary characteristics of microbialites,the depositional environments of the various types of microbialites are described,and the distribution patterns of their depositional environments are *** relationship between the development of microbialites and the evolution and radiation of metazoans during the Early to Middle Ordovician is *** with the correspondence between the stepwise and rapid radiation of metazoans and the abrupt reduction in the number of microbialites between the late Early Ordovician and the early Middle Ordovician,fossils of benthonic grazing gastropods(Ecculiomphalus)were found in the stromatolites and thrombolite of the study *** is believed that the gradual reduction in microbialites was related to the rapid increase in the abundance of *** not only graze

关键词： Microbial carbonate Stromatolites Thrombolites Oncolite Lower Ordovician Songzi Area

Essential oil of Actinidia macrosperma, a catnip response kiwi endemic to China

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第9期7卷 708-712页

作者： ZHAO yun-peng WANG xiao-yun WANG Zhi-can LU Yin FU Cheng-xin CHEN Shao-yuan Research Program for Medicinal Plant Resource Lab of Systematic ＆ Evolutionary Botany and Biodiversity School of Life Sciences Zhejiang University Hangzhou 310058. China

Objective: To identify compounds that may be responsible for catnip response of Actinidia macrosperma, and compare chemical compositions in the wild and in vitro regenerated plants. Methods: GC-MS and relative retention indices with n-alkanes as reference points were used for compound identification, and component relative percentage was calculated based on GC peak areas without using correction factors. Results: There are 28 compounds (92.72%) and 15 compounds (93.88%) identi- fied in the essential oils from the wild and regenerated plants, respectively. Dihydronepetalactone, iridomyrmecin, and dihydro- actinidiolide, which are believed to be attractive to felines, are present in both wild and regenerated plants. Actinine was not detected, and beta-pheylethyl alcohol was only present in wild plant. In addition, short-chain enol derivatives, messengers in chemical communication, are commonly present in wild plant of A. macrosperma, but absent in regenerated one. Conclusion: Dihydronepetalactone, iridomyrmecin, and dihydroactinidiolide are responsible for the catnip response of A. macrosperma.

关键词： Actinidia macrosperma GC-MS Dihydronepetalactone lridomyrmecin Dihydroactinidiolide Catnip response

基于CGE模型的能源与环境财税政策协同影响效应研究

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经济问题 2019年第7期 37-44页

作者：云小鹏中国矿业大学(北京)管理学院

在分析能源补贴相关财税政策、碳税政策理论以及国内外相关领域研究现状的基础上,通过可计算一般均衡模型理论、投入产出理论、社会核算矩阵理论以及GAMS编程方法,构建中国能源与环境财税政策的可计算一般均衡模型,收集相关基础数据,建... 详细信息

在分析能源补贴相关财税政策、碳税政策理论以及国内外相关领域研究现状的基础上,通过可计算一般均衡模型理论、投入产出理论、社会核算矩阵理论以及GAMS编程方法,构建中国能源与环境财税政策的可计算一般均衡模型,收集相关基础数据,建立模型数据库,获得了GAMS编程语言下的模拟实现。通过静态模型与动态模型综合地评价分析中国能源与环境财税价格政策对中国能源-经济-环境等相关变量的影响效应。研究一方面拓展了CGE模型研究方法在中国的发展与应用,另一方面实现了对能源与环境财税价格政策影响效应的综合评价,并为政府决策提供了有益的参考。

关键词：可计算一般均衡模型能源环境财税政策

黄河流域城镇化与生态环境耦合协调测度及交互关系研究

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经济问题 2022年第8期 86-95页

作者：云小鹏山西警察学院公安管理系山西太原030401 中国矿业大学(北京)力学与建筑工程学院北京10083

基于2004—2020年黄河流域9个省(区)数据,建立城镇化与生态环境交互关系指标体系,运用耦合协调模型、相对发展模型和交互胁迫模型,探究二者动态耦合及交互关系。结果表明:黄河流域城镇化—生态环境耦合协调度稳步提升,相对发展度逐步下... 详细信息

基于2004—2020年黄河流域9个省(区)数据,建立城镇化与生态环境交互关系指标体系,运用耦合协调模型、相对发展模型和交互胁迫模型,探究二者动态耦合及交互关系。结果表明:黄河流域城镇化—生态环境耦合协调度稳步提升,相对发展度逐步下降,“无序态→无序态与低稳态并存→低稳态→低稳态与中稳态并存”阶段有序接替;经济城镇化>社会城镇化>空间城镇化>人口城镇化,资源要素状态优于生态环境响应,生态环境压力与生态环境状态趋势基本一致,这基本符合黄河流域资源禀赋特点以及能源和粮食战略地位;黄河流域分省及整体城镇化与生态环境均存在交互胁迫关系且动态耦合关系空间分布不均衡,中下游经济发展较快省份的城镇化水平较高,上游欠发达省份承受的生态环境压力相对较高。

关键词：黄河流域城镇化生态环境耦合协调交互胁迫

Electrochemical conversion of methane to bridge the gap in the artificial carbon cycle

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Journal of Energy Chemistry 2025年第1期100卷 286-308页

作者： Yuhao peng Yuefeng Song Ihar Razanau Juanxiu xiao Wei xiao Di Hu Guoxiong Wang College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power Sources Wuhan University State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Dalian Institute of Chemical Physics Chinese Academy of Sciences Laboratory of Physical-Chemical Technologies SSPA Scientific and Practical Materials Research Centre of NAS of Belarus State Key Laboratory of Marine Resources Utilization in South China Sea Collaborative Innovation Center of Marine Science and Technology School of Marine Science and Engineering Hainan University Department of Chemical and Environmental Engineering University of Nottingham Ningbo China

Methane, an abundant one-carbon（C1） resource, is extensively used in the industrial production of vital fuels and value-added chemicals. However, current industrial methane conversion technologies are energy-and carbon-intensive, mainly due to the high activation energy required to break the inert C–H bond, low selectivity, and problematic side reactions, including CO2emissions and coke deposition. Electrochemical conversion of methane（ECM） using intermittent renewable energy offers an attractive solution, due to its modular reactor design and operational flexibility across a broad spectrum of temperatures and pressures. This review emphasizes conversion pathways of methane in various reaction systems, highlighting the significance and advantages of ECM in facilitating a sustainable artificial carbon cycle. This work provides a comprehensive overview of conventional methane activation mechanisms and delineates the complete pathways of methane conversion in electrolysis contexts. Based on surface/interface chemistry, this work systematically analyzes proposed reaction pathways and corresponding strategies to enhance ECM efficiency towards various target products, including syngas, hydrocarbons, oxygenates, and advanced carbon materials. The discussion also encompasses opportunities and challenges for the ECM process, including insights into ECM pathways, rational electrocatalyst design, establishment of benchmarking protocols, electrolyte engineering, enhancement of CH4conversion rates, and minimization of CO2emission.

关键词： Activation energy

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： xiao Xiang Feng Gao Yu-Gui peng peng Wu Zong-Lin Li Xue-Feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

一种用于大学信息技术基础课的适应性考试系统

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教育理论与实践 2017年第12期37卷 47-50页

作者：王云李小鹏山西师范大学教育技术与传媒学院山西临汾041004

基于IRT的适应性考试模型是依据项目反应理论(IRT),对计算机适应性考试中的试题参数估计、试题筛选、考生能力估算和适应性考试等核心问题进行深入研究的基础上提出的。基于IRT的适应性考试模型解决了《大学信息技术基础》课程学习中知... 详细信息

基于IRT的适应性考试模型是依据项目反应理论(IRT),对计算机适应性考试中的试题参数估计、试题筛选、考生能力估算和适应性考试等核心问题进行深入研究的基础上提出的。基于IRT的适应性考试模型解决了《大学信息技术基础》课程学习中知识测评费时、低效以及学习与测评不连贯等问题,具有一定的现实意义和应用价值。

关键词：适应性考试系统大学信息技术基础课项目反应理论适应性测验题库教育测评

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动力煤市场波动特征研究

煤炭工程 2018年第6期50卷 131-134页

作者：云小鹏中国矿业大学(北京)管理学院北京100083

寻求适合我国的动力煤价格影响因素及波动特征,对解决我国煤炭供需矛盾,实现煤炭行业的可持续发展具有重要意义。从统计学的角度和煤炭产业的角度,实现了对价格波动的解释,并为以后动力煤市场价格研究提供一个有价值的工具。统计学的角... 详细信息

寻求适合我国的动力煤价格影响因素及波动特征,对解决我国煤炭供需矛盾,实现煤炭行业的可持续发展具有重要意义。从统计学的角度和煤炭产业的角度,实现了对价格波动的解释,并为以后动力煤市场价格研究提供一个有价值的工具。统计学的角度来看,运用价VAR模型拟合波动;煤炭产业的角度来看,通过对煤炭上下游关键节点的数据,找出对煤炭价格影响较为密切的因子。两种思维角度的结合,降低了统计模型过拟合的可能性,也提高了产业链因子与价格波动之间真实关系的研究结论的可靠性,使得该模型更具有实用价值。

关键词：动力煤价格波动 VAR模型