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Journal of Computational Mathematics 2024年第2期42卷 355-371页

作者： Yanping chen Zhenrong chen Yunqing Huang School of Mathematical Sciences South China Normal UniversityGuangzhou 510631China Hunan Key Laboratory for Computation and Simulation in Science and Engineering Xiangtan UniversityXiangtan 411105China

For fractional Volterra integro-differential equations(FVIDEs)with weakly singular kernels,this paper proposes a generalized Jacobi spectral Galerkin *** basis functions for the provided method are selected generalized Jacobi functions(GJFs),which can be utilized as natural basis functions of spectral methods for weakly singular FVIDEs when appropriately *** developed method's spectral rate of convergence is determined using the L^(∞)-norm and the weighted L^(2)-*** results indicate the usefulness of the proposed method.

关键词： Generalized Jacobi spectral Galerkin method Fractional-order Volterra integ-ro-differential equations Weakly singular kernels Convergence analysis

Recent Advances in Nickel Catalyzed Carbonylative Reactions via the Insertion of Carbon Monoxide

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Chinese Journal of Chemistry 2024年第2期42卷 177-189页

作者： Xinzhou chen Gang chen Zhong Lian Department of Dermatology State Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan UniversityChengduSichuan 610041China

Carbonyl compounds have attracted considerable attention due to their extensive applications in drug ***,they are important synthetic intermediates for the construction of carbon-carbon and carbon-heteroatom ***-metal-catalyzed carbonylation via the insertion of co is one of the most efficient and straightforward strategies to access carbonyl ***,most of the transition-metal-catalyzed carbonylative reactions require expensive and toxic noble-metal ***,there is a growing demand for the exploration of nickel-catalyzed carbonylative reactions via the insertion of CO due to the earth abundance and low cost of *** with the well-established palladium-catalyzed carbonylative reactions,nickel-catalyzed analogous transformations have been relatively *** is primarily because CO strongly binds to nickel,often resulting in catalyst *** recent years,some research groups have focused on using CO surrogates or NN_(2) pincer nickel catalyst to circumvent the formation of Ni(CO)_(4).Nickel-catalyzed carbonylation has been applied in the construction of carbonyl-containing compounds,such as ketones,carboxylic acids,thioesters,acyl chloride and carboxamides.

关键词： Carbonylation Nickel catalysis Carbon monoxide C1 chemistry Carbonyl-containing compounds

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数量化理论Ⅳ及其在化探异常分类中的应用

物探化探计算技术 1989年第1期11卷 53-60页

作者：陈玉明长春地质学院

数量化理论Ⅳ为我们在分类时有效地利用定量变量和定性变量提供了一个有力的工具。本文详细地介绍了数量化理论Ⅳ的原理和计算方法,并以浙江赵家一大兼溪区域土壤地球化学异常的分类为例,说明了这种方法在化探异常分类中的应用效果。

关键词：数量化理论IV 化探数学地质

High-Level Security Dimension Evaluation of Blockchain BaaS System and Key Technology

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China Communications 2024年第6期21卷 176-191页

作者： chen Wanfa Zheng Qing’an chen Shuzhen Fu Hongyi chen Liang Fujian Police College Fuzhou 350007China Computer Science and Information Security Management Department Fujian Police CollegeFuzhou 350007China Fujian Province Key Laboratory for Digital Network Crime Supervision and Prevention Fuzhou 350007China Beijing University of Posts and Telecommunications Beijing 100876China Fujian Provincial Prison Administration Fuzhou 350002China

In recent years,blockchain technology integration and application has gradually become an important driving force for new technological innovation and industrial *** blockchain technology and applications are developing rapidly,the emerging security risks and obstacles have gradually become *** can still find security issues in blockchain systems and conduct attacks,causing increasing losses from network attacks every *** response to the current demand for blockchain application security detection and assessment in all industries,and the insufficient coverage of existing detection technologies such as smart contract detectiontechnology,this paper proposes a blockchain core technology security assessment system model,and studies the relevant detection and assessment key technologies and systems.A security assessment scheme based on a smart contract and consensus mechanism detection scheme is *** the underlying blockchain architecture supports the traceability of detection results using super ***,the functionality and performance of the system were tested,and the test results show that the model and solutions proposed in this paper have good feasibility.

关键词： blockchain security consensus mechanis smart contract

Blockchain-based immunization against kleptographic attacks

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Science China(Information Sciences) 2024年第7期67卷 172-183页

作者： Changsong JIANG Chunxiang XU Jie chen Kefei chen School of Computer Science and Engineering University of Electronic Science and Technology of China Yangtze Delta Region Institute (Huzhou) University of Electronic Science and Technology of China Department of Mathematics Hangzhou Normal University

Adversarial implementations of cryptographic primitives called kleptographic attacks cause the leakage of secret information. Subliminal channel attacks are one of the kleptographic attacks. In such attacks, backdoors are embedded in implementations of randomized algorithms to elaborately control randomness generation, such that the secrets will be leaked from biased outputs. To thwart subliminal channel attacks, double-splitting is a feasible solution, which splits the randomness generator of a randomized algorithm into two independent generators. In this paper, we instantiate double-splitting to propose a secure randomness generation algorithm dubbed SRG using two physically independent generators: ordinary and public randomness generators. Based on public blockchains, we construct the public randomness generator,which can be verified publicly. Hashes of a sufficient number of consecutive blocks that are newly confirmed on a blockchain are used to produce public randomness. In SRG, outputs from the two generators are taken as inputs of an immunization function. SRG accomplishes immunization against subliminal channel ***, we discuss the application strategies of SRG for symmetric and public-key encryption.

关键词： kleptographic attacks subliminal channel blockchain immunization randomized algorithm

Goal-Oriented Control Systems(GOCS):From HOW to WHAT

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 816-819页

作者： Wen-Hua chen the Department of Aeronautical and Automotive Engineering Loughborough UniversityLeicestershireLE113TUU.K.

Brief:New control theory is required to underpin safe design and deployment of future highly automated systems to deal with uncertain environments and complicated tasks,enabled by AI and other advanced ***-Oriented Control Systems offer potential to transform the control system design from currently instructing a control system how to perform a task to specifying what is to be achieved.

关键词： automated instru system

From ore to MOF: A case of MIL-100(Fe) production from iron ore concentrates

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Progress in Natural Science:Materials International 2024年第01期34卷 66-73页

作者： Miao Chang Chiyao Tang Chong-chen Wang chen Zhao Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation School of Environment and Energy Engineering Beijing University of Civil Engineering and Architecture

Within this work, iron ore concentrates instead of elemental iron Fe0and iron salts like Fe（NO3）3and FeCl3were selected as iron source to prepare MIL-100（Fe）(labeled as MIL-100（Fe）-ore). The corresponding synthesis cost is reduced to half of the MIL-100（Fe） produced from elemental iron and iron salts. As well, the unreacted iron ore concentrates can be easily separated from the as-prepared MIL-100（Fe）-ore by magnetic to facilitate the purification process, free of the strong acids to wash the residual iron. The as-obtained MIL-100（Fe）-ore with Langmuir surface area up to 2281.6 m2g-1displayed long-term chemical stability. Furthermore, the sorption capacity of MIL-100（Fe）-ore towards malachite green（MG） is up to 522.3 mg g-1at 25℃ and initial pH = 3.2, higher than that of MIL-100（Fe） yielded by conventional hydrothermal process. Finally, the production cost and life cycle assessment of MIL-100（Fe）-ore were compared with other traditional production procedures. The results revealed that our work greatly reduced the synthesis cost and enhanced the environmental sustainability.

关键词： Metal-organic framework Iron ore concentrates Adsorption Life cycle assessment

The evolutionary trajectory of the rural settlements in Southern Jiangsu in the past 20 years:From the perspective of urbanization and land use

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Journal of Geographical Sciences 2024年第8期34卷 1615-1635页

作者： chen Feiyu chen cheng Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and LimnologyCASNanjing 210008China Nanjing College University of Chinese Academy of SciencesNanjing 211135China

For a long time,due to lack of accurate data covering large areas,it is difficult to capture the continuous spatial evolutionary trajectory of rural settlements shaped by rapid urbanization and rural land use *** fill this gap,based on theoretical analysis this paper systemically detected the changing characteristics of scale,spatial morphology,distribution,and land use pattern of rural settlements in Southern Jiangsu in the past 20 years depending on the data of land resource survey in 2009 and *** study suggests that the total area and per capita size of rural settlements declined by 30%and 2%respectively as a result of rural land consolidation and the influx of enormous immigrants from underdeveloped *** spatial density and average shape index dropped by 14%and 44%respectively in the recent decade,indicating an evident trend of decentralization in spatial distribution,and regularization in the spatial ***,residential land within rural settlements decreased by 33%over the past decade while the land for industry and commercial service steadily increased,demonstrating that the function for manufacturing and diversified services had been *** the emerging issue of the aging population and new business opportunities in rural Southern Jiangsu,rural settlements regeneration might be the focus offutureresearch.

关键词： rural settlements spatial morphology land use Southern Jiangsu

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拉丁美洲铝土矿地质特征及资源潜力

地质通报 2017年第12期36卷 2107-2115页

作者：姚仲友陈喜峰陈玉明李汉武赵宇浩沈莽庭中国地质调查局南京地质调查中心江苏南京210016 中国地质调查局发展研究中心北京100037

介绍拉丁美洲铝土矿资源概况、地质特征及成因类型。拉丁美洲铝土矿资源主要分在巴西、苏里南、牙买加、圭亚那、委内瑞拉等国家,储量为60.3×10~8t,占世界铝土矿总储量的21.54%。巴西为拉丁美洲最大的铝土矿生产国和出口国。拉丁美洲... 详细信息

介绍拉丁美洲铝土矿资源概况、地质特征及成因类型。拉丁美洲铝土矿资源主要分在巴西、苏里南、牙买加、圭亚那、委内瑞拉等国家,储量为60.3×10~8t,占世界铝土矿总储量的21.54%。巴西为拉丁美洲最大的铝土矿生产国和出口国。拉丁美洲铝土矿成因类型主要为红土型和岩溶型2种,主要的铝土矿矿山有45座。牙买加岛弧、圭亚那地盾、中巴西地盾、圣弗朗西斯科地盾为4个铝土矿勘查开发潜力区。

关键词：铝土矿地质特征资源潜力拉丁美洲

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基因表达数据在邻域关系中的特征选择

智能系统学报 2014年第2期9卷 210-213页

作者：陈玉明吴克寿李向军厦门理工学院计算机科学与技术系福建厦门361024 南昌大学计算机科学与技术系江西南昌330031

基因特征选择是基因表达数据分析中的一种重要方法。粗糙集是一种处理不确定性、不一致性、不精确性数据的有效分类工具,其特点是保持基因表达数据集的分类能力不变,进行基因特征选择。为了避免传统粗糙集特征选择方法所必需的离散化过... 详细信息

基因特征选择是基因表达数据分析中的一种重要方法。粗糙集是一种处理不确定性、不一致性、不精确性数据的有效分类工具,其特点是保持基因表达数据集的分类能力不变,进行基因特征选择。为了避免传统粗糙集特征选择方法所必需的离散化过程带来的信息损失,将邻域粗糙集特征选择方法应用于基因的特征选取,提出了基于邻域粗糙集的基因选择方法。该方法从所有特征出发,根据特征重要度逐步删除冗余的特征,最后得到关键特征组进行分类研究。在2个标准的基因表达数据集上进行特征选取,并进行了分类实验,实验结果表明该方法是有效可行的。

关键词：粗糙集邻域关系基因表达数据特征选择分类