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Journal of Rare Earths 2024年第10期42卷 1873-1881页

作者： Tianyu Sun Mutao xu xuelu Meng Tiantian Liu Qijie Jin Chengzhang Zhu haitao xu School of Environmental Science and Engineering Nanjing Tech UniversityNanjing210009China College of Materials Science and Engineering Nanjing Tech UniversityNanjing20009Chin

Soil remediation containing numerous organic contaminants is of great significance to ecological ***,the synergetic effects of Ce-Mn/Al_(2)O_(3)with different active components on catalytic thermal desorption of chlorobenzene in soil were *** optimized Ce-Mn/Al_(2)O_(3)drastically enhance the desorption efficiency of chlorobenzene,and the corresponding conversion reaches 100%within 1 h at a low temperature of 120℃.The superior performance is ascribed to the formation of Ce-Mn solid solution during the calcination process,resulting in a certain lattice change to the generation of abundant oxygen vacancies and acidic *** with the analysis of in-situ diffuse reflectance infrared spectroscopy and gas chromatography-mass spectrometry,the final products of chlorobenzene are decomposed into CO_(2),H_(2)O,Cl_(2)and *** work sheds light on the rational design of highly-active catalysts for practical applications of sustainable soil remediation.

关键词： Ce-Mn/Al_(2)O_(3) Soil Thermal desorption Low temperature Degradation pathway Rare earths

Wafer-scale carbon-based CMOS PDK compatible with siliconbased VLSI design flow

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Nano Research 2024年第8期17卷 7557-7566页

作者： Minghui Yin haitao xu Yunxia You Ningfei Gao Weihua Zhang Hongwei Liu Huanhuan Zhou Chen Wang Lian-Mao Peng Zhiqiang Li Institute of Microelectronics Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China State Key Lab of Fabrication Technologies for Integrated Circuits Beijing 100029China Beijing Hua Tan Yuan Xin Electronics Technology Co. Ltd.Beijing 101399China Institute of Carbon-based Thin Film Electronics Peking UniversityShanxi 030012China Key Laboratory for the Physics and Chemistry of Nanodevices and Center for Carbon-based Electronics School of ElectronicsPeking UniversityBeijing 100871China

Carbon nanotube field-effect transistors(CNTFETs)are increasingly recognized as a viable option for creating high-performance,low-power,and densely integrated circuits(ICs).Advancements in carbon-based electronics,encompassing materials and device technology,have enabled the fabrication of circuits with over 1000 gates,marking carbon-based integrated circuit design as a burgeoning field of research.A critical challenge in the realm of carbon-based very-large-scale integration(VLSI)is the lack of suitable automated design methodologies and infrastructure *** this study,we present the development of a waferscale 3μm carbon-based complementary metal-oxide-semiconductor(CMOS)process design kit(PDK)(3μm-CNTFETs-PDK)compatible with silicon-based Electronic Design Automation(EDA)tools and VLSI circuit design *** proposed 3μm-CNTFETs-PDK features a contacted gate pitch(CGP)of 21μm,a gate density of 128 gates/mm^(2),and a transistor density of 554 transistors/mm^(2),with an intrinsic gate delay around 134 *** of the 3μm-CNTFETs-PDK was achieved through the successful design and tape-out of 153 standard cells and 333-stage ring oscillator *** the carbon-based PDK and a silicon-based design platform,we successfully implemented a complete 64-bit static random-access memory(SRAM)circuit system for the first time,which exhibited timing,power,and area characteristics of clock@10 kHz,122.1μW,3795μm×2810μ*** research confirms that carbon-based IC design can be compatible with existing EDA tools and silicon-based VLSI design flow,thereby laying the groundwork for future carbon-based VLSI advancements.

关键词： carbon nanotube field-effect transistors(CNTFETs) complementary metal-oxide-semiconductor(CMOS) process design kit(PDK) wafer-scale very-large-scale integration(VLSI)

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沉积植物古DNA在第四纪植被重建中的应用

地球科学进展 2024年第8期39卷 801-812页

作者：徐海涛李泉赵艳中国科学院地理科学与资源研究所陆地表层格局与模拟院重点实验室北京100101 中国科学院大学北京100049

沉积植物古DNA是分析古植被信息的前沿手段,可以从分子生物学视角为古植被和古环境重建提供更开阔的视野。分析了沉积植物古DNA保存的主要影响因素;概述了沉积植物古DNA分析流程;综述了沉积植物古DNA在重建植物群落动态演变过程、气候... 详细信息

沉积植物古DNA是分析古植被信息的前沿手段,可以从分子生物学视角为古植被和古环境重建提供更开阔的视野。分析了沉积植物古DNA保存的主要影响因素;概述了沉积植物古DNA分析流程;综述了沉积植物古DNA在重建植物群落动态演变过程、气候与环境变化以及生态演化对人类活动的响应等领域的相关研究进展,沉积植物古DNA分析通过提供快速和高分辨率的古植物物种信息,能够重建植物群落演变过程,定量、半定量重建古气候,并探究人类农牧活动对生态系统的影响。未来的研究中应该构建更加完善的植物物种DNA分类参考数据库,加强沉积植物古DNA分子的埋藏学研究,推广其在第四纪古环境研究中的应用,同时构建多指标记录以获得更完整的古生态信息。沉积植物古DNA将在古植被与气候变化以及人类活动关系研究中发挥更广泛的作用。

关键词：沉积植物古DNA 第四纪植被重建古DNA分析

自构建关联噪声下的随机共振及其在故障诊断上的应用

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振动与冲击 2024年第11期43卷 297-305页

作者：徐海涛杨涛周生喜西北工业大学航空学院西安710072 西北工业大学深圳研究院深圳518057

轴承作为旋转机械的重要组件之一,及时对其进行健康监测与更换可有效避免设备停机,减少经济损失。首先基于自构建关联噪声驱动下的随机共振系统(stochastic resonance system driven by self-constructingly correlated noise, DSCSR),... 详细信息

轴承作为旋转机械的重要组件之一,及时对其进行健康监测与更换可有效避免设备停机,减少经济损失。首先基于自构建关联噪声驱动下的随机共振系统(stochastic resonance system driven by self-constructingly correlated noise, DSCSR),推导了在正弦激励下该系统输出的理论信噪比(signal-to-noise ratio, SNR)。研究发现通过调节此非线性系统的参数可观察到随机共振现象。其次,针对将随机共振现象用于故障诊断时需要准确的先验知识这一局限性,进一步提出了基于功率谱的信噪比评价指标,并以此来确定非线性系统随机共振发生时的最优系统参数,对最优参数系统输出信号进行功率谱分析来判断故障类型。最后,通过轴承故障诊断试验以及实际风机轴承内圈故障实例证明了DSCSR方法的有效性,以及其增强微弱故障特征并抑制其他谐波以及噪声的干扰的能力。

关键词：关联噪声随机共振故障诊断非线性系统

中国杂交水稻在非洲的技术积累及其可持续发展

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西亚非洲 2024年第1期 131-151,156页

作者：文春晖徐海涛湖南农业大学经济学院湖南农业大学中非农业合作与发展基地

杂交水稻技术作为缓解世界粮食短缺问题的重要工具,为中非农业合作带来了深远的积极影响。中非杂交水稻技术合作始于20世纪90年代初期,现已从杂交水稻试验示范、本土化育种初探阶段发展至本土化制种及全产业链合作初创的新阶段。由中国... 详细信息

杂交水稻技术作为缓解世界粮食短缺问题的重要工具,为中非农业合作带来了深远的积极影响。中非杂交水稻技术合作始于20世纪90年代初期,现已从杂交水稻试验示范、本土化育种初探阶段发展至本土化制种及全产业链合作初创的新阶段。由中国主导的马达加斯加杂交水稻商业化运作全产业链合作体系,不仅为马达加斯加粮食振兴计划的增产目标夯实了基础,而且为中国农业技术在非洲开展属地和商业化产业合作发挥了良好的示范和推动作用。然而,杂交水稻技术合作的复杂性使之在其他非洲国家的大面积推广面临一些挑战,具体而言,包括合作目标国农业投入不足、农田水利设施匮乏、农业技术人才缺乏、产业发展资金不足、不同政治集团的利益纷争与国际舆论环境的压力等多重制约因素。与此同时,非洲国家建立自主可控粮食安全体系的紧迫性、中非提升粮食生产战略与政策的高度契合性、中非经贸博览会创立提供的新动能,以及中非农业合作挑战因素的长期性、复杂性,使未来中非杂交水稻技术合作得以渐进性发展与深化具备了条件。

关键词：中非合作农业技术合作杂交水稻技术农业技术积累全产业链

Lagrangian view of time irreversibility of fluid turbulence

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Science China(Physics,Mechanics & Astronomy) 2016年第1期59卷 7-15页

作者： haitao xu Center for Combustion Energy and Department of Thermal Engineering Tsinghua UniversityBeijing 100084China Max Planck Institute for Dynamics&Self-Organization(MPIDS) Gottingen D-37077Germany Ecole Normale Superieure de Lyon Lyon F-69007France Institute for Nonlinear Dynamics University of Gottingen GSttingen D-37077Germany Laboratory of Atomic and Solid State Physics and Sibley School of Mechanical and Aerospace Engineering Cornell UniversityIthaca NY 14853USA

A turbulent flow is maintained by an external supply of kinetic gradients. The scale at which energy is supplied greatly differs energy, which is eventually dissipated into heat at steep velocity from the scale at which energy is dissipated, the more so as the turbulent intensity （the Reynolds number） is larger. The resulting energy flux over the range of scales, intermediate between energy injection and dissipation, acts as a source of time irreversibility. As it is now possible to follow accurately fluid particles in a turbulent flow field, both from laboratory experiments and from numerical simulations, a natural question arises： how do we detect time irreversibility from these Lagrangian data？ Here we discuss recent results concerning this problem. For Lagrangian statistics involving more than one fluid particle, the distance between fluid particles introduces an intrinsic length scale into the problem. The evolution of quantities dependent on the relative motion between these fluid particles, including the kinetic energy in the relative motion, or the configuration of an initially isotropic structure can be related to the equal-time correlation functions of the velocity field, and is therefore sensitive to the energy flux through scales, hence to the irreversibility of the flow. In contrast, for single- particle Lagrangian statistics, the most often studied velocity structure functions cannot distinguish the ＂arrow of time＂. Recent observations from experimental and numerical simulation data, however, show that the change of kinetic energy following the particle motion, is sensitive to time-reversal. We end the survey with a brief discussion of the implication of this line of work.

关键词： fluid turbulence time irreversibility energy cascade Lagrangian description

Recognizing Social Function of Urban Regions by Using Data of Public Bicycle Systems

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Chinese Journal of Electronics 2019年第1期28卷 13-20页

作者： xu haitao YING Jing College of Computer Science and Technology Zhejiang University

Obtaining the classification of urban functions is an integral part of urban planning. Currently,public bicycle systems are booming in these years. It conveys human mobility and activity information, which can be closely related to the social function of an urban region. This paper discusses the potential use of public bicycle systems for recognizing the social function of urban regions by using one year’s rent/return data of public bicycles. We found that rent/return dynamics, extracted from public bicycle systems, exhibited clear patterns corresponding to the urban function classes of these regions. With seven features designed to characterize the rent/return pattern, our method based on Smooth support vector machine(SSVM) is proposed to recognize social function classes of urban regions. We evaluate our method based on the large-scale real-world dataset collected from the public bicycle system of Hangzhou. The results show that our method can efficiently recognize different types of urban function areas. Classification results using the proposed SSVM achieved the best classification accuracy of 96.15%.

关键词： Urban regions recognition Public bicycle system Social function classification Smooth support vector machine(SSVM)

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基于深度强化学习的自学习排课遗传算法研究

计算机科学 2024年第S1期51卷 229-236页

作者：徐海涛程海燕童名文华中师范大学人工智能教育学部武汉430079

排课是教学活动中一项常规而重要的事项,传统的人工排课方式费时费力,且容易出现错误,无法满足大规模排课的需求,而经典排课遗传算法存在收敛速度过快、排课效率随约束因素的增加而下降等问题。针对已有排课遗传算法存在的问题,提出一... 详细信息

排课是教学活动中一项常规而重要的事项,传统的人工排课方式费时费力,且容易出现错误,无法满足大规模排课的需求,而经典排课遗传算法存在收敛速度过快、排课效率随约束因素的增加而下降等问题。针对已有排课遗传算法存在的问题,提出一种基于深度强化学习的自学习排课遗传算法(GA-DRL)。GA-DRL算法利用Q-learning算法,实现了交叉参数和变异参数的自适应调整,增强了遗传算法的搜索能力,通过建立马尔可夫决策过程(MDP)的参数动态调整模型,对种群适应度函数进行状态集合的分析,实现对种群的整体性能的综合评价。同时将深度Q-网络算法(DQN)引入调度问题中,以解决排课中种群状态多、Q表数据量大的问题。实验结果表明,与经典排课遗传算法和改进的遗传算法相比,GA-DRL算法在正确率和寻优能力上有所提升。所提算法还可以应用于考场安排、电影院的排座和航空航线规划等问题。

关键词：排课问题遗传算法 Q-学习深度Q-网络

Self-Organized Algorithm in LTE Networks： A Utility Function Based Optimal Power Control Scheme

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China Communications 2014年第A02期11卷 95-101页

作者： xu haitao AN Jianwei School of Computer and Communication Engineering University of Science and Technology Beijing (USTB) Beijing 100083 ER. China

In this paper, transmission power control problem for uplink LTE network is investigated and a new autonomic uplink power control scheme was proposed based on utility function, which is a self- organized algorithm. The whole approach is based on the economic concept named utility function. Then a self-organized algorithm is distributed in each mobile users to control the transmission power and to maximize the transmission utility. The proposed scheme is solved through the Lagrange multiplier technique. It is proved that the utility function based algorithm optimal power level can be model. is applicable and the achieved based on our

关键词： self-organized power control utilityfunction LTE networks lagrange multiplier

130203综放工作面综合防灭火技术研究与实践

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华北科技学院学报 2024年第2期21卷 7-12页

作者：黄旭何伟蒋彦兵张庆龙许海涛宁夏煤业有限责任公司枣泉煤矿银川750000 华北科技学院北京东燕郊065201

130203工作面采用走向长壁综采放顶煤采煤法,所采2#煤层属于易自燃煤层。为预防在回采期间工作面出现自燃发火的现象,结合130203综放工作面实际开采情况,采用预测、治理及效果监测的全过程研究方法,确定了自燃发火预测预报,封堵采空区漏... 详细信息

130203工作面采用走向长壁综采放顶煤采煤法,所采2#煤层属于易自燃煤层。为预防在回采期间工作面出现自燃发火的现象,结合130203综放工作面实际开采情况,采用预测、治理及效果监测的全过程研究方法,确定了自燃发火预测预报,封堵采空区漏风,工作面上、下段采空区灌注防灭火材料,采空区灌浆、注惰性气体等综合防灭火技术方案,并制定了近距离、远距离、小面积、大面积应急灭火方案。经实践证明130203综放工作面回采期间,工作面煤层未出现自燃迹象及险情,达到了预期的防治效果,保障了工作面的安全生产。

关键词：综放工作面煤层自燃发火封堵采空区灌浆注惰性气体