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零碳实验室建设方案

实验室检测

实验室检测 2024年第2期2卷 78-83页

作者：孙伟卢俊琛莫层聪刘亮俊嘉兴市恒光电力建设有限责任公司安大安全工器具检测中心嘉兴314000 九郡绿建技术(嘉兴)有限公司嘉兴314000

为探索建设零碳实验室方案,开发低碳技术和寻求相关难题解决方案,以减少能源消耗和碳排放量来解决环境问题。通过先进的技术及实践探索,建立和完善低碳经济体系,扩大相关产业规模来促进经济结构优化。本文所研究的检测实验室建设方案中... 详细信息

为探索建设零碳实验室方案,开发低碳技术和寻求相关难题解决方案,以减少能源消耗和碳排放量来解决环境问题。通过先进的技术及实践探索,建立和完善低碳经济体系,扩大相关产业规模来促进经济结构优化。本文所研究的检测实验室建设方案中运行阶段自主减排、可再生能源利用、碳汇等措施实施后,实验室碳排放量为负值,可被定义为零碳实验室。建设零碳实验室作为全球环保和节能减排的重要行动之一,也被视作倡导可持续发展的生态文明观念的实际落实者。从中可以更深层次地理解并促进人类走向可持续、低碳未来的发展方向。

关键词：零碳实验室减碳措施碳监测实验室建设

Vibration absorption of parallel-coupled nonlinear energy sink under shock and harmonic excitations

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Applied Mathematics and Mechanics(English Edition) 2021年第8期42卷 1135-1154页

作者： Jian’en chen Wei ZHANG jun LIU Wenhua HU Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical EngineeringTianjin University of TechnologyTianjin 300384China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of TechnologyTianjin 300384China Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Structures College of Mechanical EngineeringBeijing University of TechnologyBeijing 100124China

Nonlinear energy sink(NES)can passively absorb broadband energy from primary *** multiple NESs connected in parallel exhibit superior performance to single-degree-of-freedom(SDOF)*** this work,a linear coupling spring is installed between two parallel NESs so as to expand the application scope of such vibration *** vibration absorption of the parallel and parallel-coupled NESs and the system response induced by the coupling spring are *** results show that the responses of the system exhibit a significant difference when the heavier cubic oscillators in the NESs have lower stiffness and the lighter cubic oscillators have higher ***,the efficiency of the parallel-coupled NES is higher for medium shocks but lower for small and large shocks than that of the parallel *** parallel-coupled NES also shows superior performance for medium harmonic excitations until higher response branches are *** performance of the parallel-coupled NES and the SDOF NES is *** is found that,regardless of the chosen SDOF NES parameters,the performance of the parallel-coupled NES is similar or superior to that of the SDOF NES in the entire force range.

关键词： coupling influence nonlinear energy sink(NES) vibration absorption

中国农村家庭分化对耕地利用方式的影响——基于全国百县万家农户的调查

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自然资源学报 2024年第2期39卷 392-410页

作者：陈韵凌王茂军曹广忠刘涛蔡蓓蕾首都师范大学资源环境与旅游学院北京100048 北京大学城市与环境学院北京100871

城镇化背景下,人口的规模外流重塑了中国农村家庭类型,耕地利用方式相应呈多元化特征。区别于既往强调家庭特征的独立指标,本文提供了一种兼顾家庭离村情况、留村人口代际组合的农村家庭类型划分范式,并构建了农户耕地利用决策假说。基... 详细信息

城镇化背景下,人口的规模外流重塑了中国农村家庭类型,耕地利用方式相应呈多元化特征。区别于既往强调家庭特征的独立指标,本文提供了一种兼顾家庭离村情况、留村人口代际组合的农村家庭类型划分范式,并构建了农户耕地利用决策假说。基于全国抽样的万份农户问卷数据,采用多项Logit模型分析了农村家庭类型分化对耕地利用方式的影响。研究发现:(1)全家在村家庭比率呈“东—中—西”递减态势,城乡两栖家庭比率呈“东—中—西”递增态势。留村人口中,中坚型农户集中于东部,完整型、老幼型农户集中于中、西部。(2)全家在村家庭倾向于种植经济作物;城乡两栖家庭倾向于土地转出及种植粮食。(3)全家在村的中坚型、完整型农户分别倾向于种植粮食、经济作物;城乡两栖的中坚型、完整型农户倾向于种植粮食作物,老幼型农户倾向于转出、撂荒耕地或种植林木。(4)农村家庭的本地非农就业、地块数量、家庭资产、农业补贴等因素也对耕地利用方式产生显著影响。研究结论可为耕地用途管制政策的顶层设计提供农村家庭耕地决策行为的底层逻辑,为因户、因类施策依据提供现实参考。

关键词：农村家庭耕地利用方式耕地非粮化土地流转耕地撂荒影响因素

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基于改进云模型的隧道爆破效果综合评价研究

工程爆破 2024年第3期30卷 8-19页

作者：金圆岳中文王毅陈佳瑶赵颖中国矿业大学(北京)力学与土木工程学院北京100083

针对隧道爆破效果综合评价的不确定性问题,提出基于改进云模型与组合赋权的评价方法。结合现场工程经验与相关研究,选择平均线性超挖量、平均线性欠挖量、炮孔利用率、周边孔半孔痕率、大块率以及炸药单耗为评价指标,结合序关系分析(G1... 详细信息

针对隧道爆破效果综合评价的不确定性问题,提出基于改进云模型与组合赋权的评价方法。结合现场工程经验与相关研究,选择平均线性超挖量、平均线性欠挖量、炮孔利用率、周边孔半孔痕率、大块率以及炸药单耗为评价指标,结合序关系分析(G1)法与基于指标相关性(CRITIC)法对各指标赋权,借助改进云模型对爆破效果数值及等级区间进行同向化处理,从而构建爆破效果综合评价模型。以某隧道为实例进行验证,模型分析结果表明在当前的爆破设计方案和生产水平下该隧道爆破效果的综合评价等级为“较好”,指明了影响爆破效果的主要因素,为进一步优化爆破设计参数提供了方向。

关键词：隧道爆破效果改进云模型组合赋权综合评价模型评价等级

Graphene-based silicon modulators

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Frontiers of Information Technology & Electronic Engineering 2019年第4期20卷 458-471页

作者： Hao-wen SHU Ming jin Yuan-sheng TAO Xing-jun WANG State Key Laboratory on Advanced Optical Communication Systems and Networks Department of ElectronicsSchool of Electronics Engineering and Computer Science Peking University Nano-optoelectronics Frontier Center of Ministry of Education at Peking University

Silicon photonics is a promising technology to address the demand for dense and integrated nextgeneration optical interconnections due to its complementary-metal-oxide-semiconductor(CMOS) ***, one of the key building blocks, the silicon modulator, suffers from several drawbacks, including a limited bandwidth, a relatively large footprint, and high power consumption. The graphene-based silicon modulator, which benefits from the excellent optical properties of the two-dimensional graphene material with its unique band structure,has significantly advanced the above critical figures of merit. In this work, we review the state-of-the-art graphenebased silicon modulators operating in various mechanisms, i.e., thermal-optical, electro-optical, and plasmonic. It is shown that graphene-based silicon modulators possess the potential to have satisfactory characteristics in intra-and inter-chip connections.

关键词： Silicon photonics Graphene Optical modulator

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基于子句单元的异构图网络抽取式文本摘要

中文信息学报 2024年第6期38卷 119-128页

作者：林群凯陈钰枫徐金安张玉洁刘健北京交通大学交通数据分析与挖掘北京市重点实验室北京100044

的目标是将长文本进行压缩、归纳和总结,从而形成具有概括性含义的短文本,其能帮助人们快速获取文档的主要信息。当前大多数的抽取式文本摘要的研究都是以整句作为抽取单元,而整句作为抽取单元会引入冗余信息,因此该文考虑使用粒度更细... 详细信息

的目标是将长文本进行压缩、归纳和总结,从而形成具有概括性含义的短文本,其能帮助人们快速获取文档的主要信息。当前大多数的抽取式文本摘要的研究都是以整句作为抽取单元,而整句作为抽取单元会引入冗余信息,因此该文考虑使用粒度更细的抽取单元。已有研究表明,细粒度的子句单元比整句单元在抽取式摘要上更具有优势。结合当下热门的图神经网络,该文提出了一种基于子句单元异构图网络的抽取式摘要模型,有效融合了词、实体和子句单元等不同层次的语言信息,能够实现更细粒度的抽取式摘要。在大规模基准语料库(CNN/DM和NYT)上的实验结果表明,该模型产生了突破性的性能并优于以前的抽取式摘要模型。

关键词：子句异构图抽取式摘要

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备件需求预测中的不确定性问题研究综述

科学技术与工程 2024年第4期24卷 1338-1346页

作者：王小巍陈砚桥金家善徐鸿羽海军工程大学动力工程学院武汉430033 陆军工程大学军械士官学校武汉430075 国防科技大学信息通信学院武汉430010

备件需求不确定性表现为随机性、多样性、时变性、信息不充分性,预测过程中很难精确地描述备件消耗与影响因素之间错综复杂的关系。以智能计算理论为代表的处理不确定性的各种方法和工具迅速发展。梳理处理备件需求预测不确定性的相关文... 详细信息

备件需求不确定性表现为随机性、多样性、时变性、信息不充分性,预测过程中很难精确地描述备件消耗与影响因素之间错综复杂的关系。以智能计算理论为代表的处理不确定性的各种方法和工具迅速发展。梳理处理备件需求预测不确定性的相关文献,按照不确定性的随机性、模糊性、不完全性、复合不确定性四大类属性,对每个大类分别进行了综述,并总结了相关研究的局限性与发展方向。研究成果可为装备备件管理提供参考。

关键词：备件需求预测智能计算不确定性

Formation and characterization of self-lubricated carbide layer on AA6082 Al-Mg-Si aluminum alloy by electrical discharge alloying process

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Transactions of Nonferrous Metals Society of China 2016年第12期26卷 3205-3218页

作者： Wang-Chih chen Hung-Mao LIN jun-Yen UAN Department of Materials Science and Engineering National Chung Hsing University Department of Mechanical Engineering Far East University

The surface modification on the AA6082 Al?Mg?Si aging-hardenable aluminum alloy was investigated by electricaldischarge alloying (EDA) process. Kerosene, used as a dielectric fluid, was pyrolytically decomposed into carbon for the formationof a self-lubricated carbide layer on the aluminum alloy surface during EDA process. Transmission electron microscopy (TEM)image found that the self-lubricated carbide layer was a multi-phase material with carbides and graphite. As a result, theEDA-modified aluminum alloy had a negligible wear rate of ~2?10?4 mg/m (c. f. ~1.1?10?2 mg/m for aluminum alloy substrate).Notably, a new characteristic was found that the EDA-processed carbide layer was a soft magnet, which improved theelectromagnetic interference (EMI) shielding performance of the alloy.

关键词： Al-Mg-Si aluminum alloy surface modification electrical discharge alloying self-lubricating pyrolytic carbon electromagnetic interference shielding

Backpropagation neural network method in data processing of ultrasonic imaging logging-while-drilling

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Applied Geophysics 2021年第2期18卷 159-170,272页

作者： Zhao Jian Lu jun-Qiang Wu jin-Ping Men Bai-Yong chen Hong-Zhi State Key Laboratory of Petroleum Resources and Prospecting at China University of Petroleum Beijing 102249China College of Geophysics China University of PetroleumBeijing 102249China SINOPEC Engineering Technology Research Institute Beijing 102200China

The existing methods for extracting the arrival time and amplitude of ultrasonic echo cannot eff ectively avoid the local interference of ultrasonic signals while drilling,which leads to poor accuracy of the echo arrival time and amplitude extracted by an ultrasonic imaging logging-while-drilling *** this study,a demodulation algorithm is used to preprocess the ultrasonic simulation signals while drilling,and we design a backpropagation neural network model to fit the relationship between the waveform data and time and *** ultrasonic imaging logging model is established,and the finite element simulation software is used for forward *** response under diff erent measurement conditions is simulated by changing the model parameters,which are used as the input layer of the neural network model;The ultrasonic echo signal is considered as a low-frequency signal modulated by a high-frequency carrier signal,and a low-pass fi lter is designed to remove the high-frequency signal and obtain the low-frequency envelope *** the amplitude of the envelope signal and its corresponding time are extracted as an output layer of the neural network *** comparing the application eff ects of the various training methods,we fi nd that the conjugate gradient descent method is the most suitable method for solving the neural network *** performance of the neural network model is tested using 11 groups of simulation test data,which verify the eff ectiveness of the model and lay the foundation for further practical application.

关键词： ultrasonic imaging logging-while-drilling finite element simulation demodulation BP neural network