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Security Considerations on Three-Factor Anonymous Authentication Scheme for WSNs 认领
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作者 Hyunsung Kim Beaton Ofesi Denice Kapito 《电脑和通信(英文)》 2021年第3期1-9,共9页
Wireless sensor networks (WSNs) are used to monitor various environmental conditions including movement, pollution level, temperature, humidity, and etc. Secure authentication is very important for the success of WSNs... Wireless sensor networks (WSNs) are used to monitor various environmental conditions including movement, pollution level, temperature, humidity, and etc. Secure authentication is very important for the success of WSNs. Li <i>et al</i>. proposed a three-factor anonymous authentication scheme in WSNs over Internet of things (IoT). They argued that their authentication scheme achieves more security and functional features, which are required for WSNs over IoT. Especially, they insisted that their user authentication scheme provides security against sensor node impersonation attack, and resists session-specific temporary information attack and various other attacks. However, this paper shows some security weaknesses in Li <i>et al</i>.’s scheme, especially focused on sensor node masquerading attack, known session-specific temporary information attack and deficiency of perfect forward secrecy. Especially, security considerations are very important to the modern IoT based applications. Thereby, the result of this paper could be very helpful for the IoT security researches. 展开更多
关键词 Security Considerations on Three-Factor Anonymous Authentication Scheme for WSNs
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Crank-Nicolson拟合有限体积法定价机制转换下的欧式期权 认领
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作者 甘小艇 张小乐 郑伟 《高等学校计算数学学报》 CSCD 北大核心 2021年第1期59-82,共24页
This paper develops and analyses a novel numerical scheme to price European options under regime switching model which is governed by a system of partial differential equations(PDEs).To numerically solve these PDEs,we... This paper develops and analyses a novel numerical scheme to price European options under regime switching model which is governed by a system of partial differential equations(PDEs).To numerically solve these PDEs,we introduce a fitted finite volume method for the spatial discretization,coupled with the Crank-Nicolson time stepping scheme.We show that this scheme is consistent,stable and monotone,and hence the convergence of the numerical solution to the viscosity solution of the continuous problem is guaranteed.Numerical experiments are presented to demonstrate the accuracy,efficiency and robustness of the new numerical method. 展开更多
关键词 Option pricing regime switching fitted finite volume method Crank-Nicolson scheme.
Highway Concrete Guardrail Lifting Scheme and Safety Performance Verification 认领
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作者 Ronggui Zhou Yidan Xie Jiangang Qiao 《交通科技期刊(英文)》 2021年第1期1-13,共13页
In order to achieve the old fence of reuse, improve the safety performance of guardrail, barrier structure does not meet the requirements, make full use of the old concrete guardrail on the basis of heightening, throu... In order to achieve the old fence of reuse, improve the safety performance of guardrail, barrier structure does not meet the requirements, make full use of the old concrete guardrail on the basis of heightening, through computer simulation experiment were analyzed, and optimization design, through the real car collision test, make the concrete guardrail after heightening structure satisfies the requirement of </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">safety performance of current specification. The results show that the protective performance of the two guardrail schemes meets the requirements of the current guardrail evaluation standards through the computer simulation experiment. Through the optimized design of scheme 1, the actual car crash test proves that the enhanced structure of Minhua TYPE II concrete guardrail can meet the requirements of safety performance evaluation. The research results provide an important basis for the transformation of </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">guardrail and the revision of the current design of expressway in China. 展开更多
关键词 Concrete Guardrail Scheme Optimization SIMULATION Real Vehicle Collision Safety Performance
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机车车辆轮对内距尺检定装置计量比对 认领
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作者 武文君 孙涛 +1 位作者 李晓峥 李明旺 《铁道技术监督》 2021年第1期17-21,共5页
在阐述计量比对定义基础上,分别从比对实验室、比对项目和方法、比对路线和时间安排、传递装置、比对试验过程、参考值及其测量不确定度、参比实验室结果报告共7个方面,论述机车车辆轮对内距尺检定装置的计量比对方案。通过处理计量比... 在阐述计量比对定义基础上,分别从比对实验室、比对项目和方法、比对路线和时间安排、传递装置、比对试验过程、参考值及其测量不确定度、参比实验室结果报告共7个方面,论述机车车辆轮对内距尺检定装置的计量比对方案。通过处理计量比对结果,分析个别参比实验室比对结果未达到合理预期的原因,提出建议,为进一步保障内距尺量值传递的准确可靠奠定基础。 展开更多
关键词 轮对内距尺 检定装置 计量比对 方案 评价
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信号道岔设计方案对联锁关系的影响与分析 认领
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作者 张昌平 周章海 《铁路通信信号工程技术》 2021年第1期91-94,共4页
道岔控制分为单动道岔和多动道岔,多动道岔又包括双动、三动、四动等联动道岔。道岔的设计方案直接关联着信号联锁关系,围绕渡线道岔单双动不同的设计方案,分析对信号系统的影响,以增强安全管控意识。
关键词 道岔 方案 联锁 影响 分析
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辽宁畜禽粪污资源化利用存在的问题和解决方案 认领
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作者 王瑞琦 《农业科技与装备》 2021年第1期87-88,共2页
畜禽粪污资源化利用是辽宁现代农业贯彻绿色发展理念、促进畜牧业转型升级、提高农业可持续发展能力的重要举措。介绍辽宁畜禽粪污资源化利用工作进展情况,分析存在的主要问题,有针对性地提出解决方案,以期为促进辽宁畜禽粪污资源化利... 畜禽粪污资源化利用是辽宁现代农业贯彻绿色发展理念、促进畜牧业转型升级、提高农业可持续发展能力的重要举措。介绍辽宁畜禽粪污资源化利用工作进展情况,分析存在的主要问题,有针对性地提出解决方案,以期为促进辽宁畜禽粪污资源化利用提供参考。 展开更多
关键词 畜禽粪污 资源化利用 问题 方案
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高效的CdS/Ti-Fe2O3异质结光阳极:研究Z型电荷迁移机制增强光电化学水氧化活性 认领
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作者 李银银 武倩楠 +5 位作者 步琦璟 张凯 林艳红 王德军 邹晓新 谢腾峰 《催化学报》 SCIE EI CAS CSCD 北大核心 2021年第5期762-771,共10页
近年来以Z型机制为转移的光催化体系成微光电化学分解水领域的研究热点.相比较传统的异质结,Z型异质结能够保留具有高氧化能力与高还原能力的位点,从而提高光电化学效率.其中,证明电荷的Z型迁移机制成为研究人员努力的方向,比较有效的... 近年来以Z型机制为转移的光催化体系成微光电化学分解水领域的研究热点.相比较传统的异质结,Z型异质结能够保留具有高氧化能力与高还原能力的位点,从而提高光电化学效率.其中,证明电荷的Z型迁移机制成为研究人员努力的方向,比较有效的证明方法包括自由基捕获、XPS分析和检测还原位点等.对于Z型异质结,界面电场处电荷的迁移行为是至关重要的,但目前常用的证明手段对界面电场处电荷的迁移行为研究还比较少.因此,本文精心设计了CdS/Ti-Fe2O3异质结光阳极来探索光电化学分解水中的电荷转移行为.采用开尔文探针测试、表面光电压谱测试和瞬态光电压谱测试等光物理测试手段监测CdS/Ti-Fe2O3Z型异质结光阳极界面电场中光生电荷的迁移行为.其中,开尔文探针和表面光电压测量表明,CdS/Ti-Fe2O3界面驱动力有利于激发电子快速迁移至CdS;由于Z型异质结是一个双光子的过程,因此在瞬态光电压的过程中采取了双光束策略,即用不同波长的光分别从两个半导体侧进行照光,以充分发挥内层CdS的电子传输层的作用.结果表明,在双光束照射下界面电场增强,使得更多Ti-Fe2O3电子与CdS空穴结合,使得更多Ti-Fe2O3电子与CdS空穴结合,更多的空穴迁移到Ti-Fe2O3的表面去参与反应,充分证明了CdS/Ti-Fe2O3光阳极的Z型迁移机制.基于界面电场有效的电荷迁移与分离的分析,对Z型异质结光阳极进行了光电化学的测试,与单纯Ti-Fe2O3光阳极相比,CdS/Ti-Fe2O3光阳极表现出优异的光电化学性能.其中,25CdS/Ti-Fe2O3光阳极的光电流密度在1.23V(相对于标准氢电极)达到1.94 mA/cm2,比单纯Ti-Fe2O3光电流高出两倍.阻抗测试结果表明,CdS/Ti-Fe2O3光阳极能够减小电荷传输阻力,从而加快电荷分离效率,这也间接证明了Z型光阳极的成功构筑,因此,本文提供 展开更多
关键词 CdS/Ti-Fe2O3 Z型 电荷迁移 界面电场 异质结光阳极
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Discussion on the Technological Path of Promoting the Sponge City Construction by Systematic Scheme in Small Catchment 认领
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作者 Aibing HU 《气象与环境研究:英文版》 CAS 2021年第1期52-58,62,共8页
Construction of the sponge city by small catchment is going to be the fundamental approach to contiguously promote the development of sponge city during the next phase in China.An effective guiding scheme to guarantee... Construction of the sponge city by small catchment is going to be the fundamental approach to contiguously promote the development of sponge city during the next phase in China.An effective guiding scheme to guarantee the contiguous promotion of sponge city is the systematic scheme of sponge city.An area in Shenzhen is taken as an example,and the compiling method and challenges of systematic scheme of sponge city are explored,principally including the targets setting under small catchment,the structure of overall thinking,compiling the scheme of runoff emission reduction from the source,perfecting aquatic environment,promoting water safety by the orientation of objective and issue,as well as the integration of each scheme and arrangement of construction mission. 展开更多
关键词 Small catchment Sponge city Systematic scheme
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Numerical Experiments of Three Boundary Layer Parameterization Schemes on Simulation Results of Low-vortex Rainstorm Weather in Langfang Region 认领
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作者 Min PENG Qingchuan WANG +2 位作者 Wenxia YANG Yaqing HONG Pengju JIN 《气象与环境研究:英文版》 CAS 2021年第1期59-62,共4页
Using mesoscale numerical model WRFV3.7,simulation tests of a low-vortex rainstorm were carried out in Langfang area,and simulation results of three boundary layer parameterization schemes(MYJ,YSU,ACM2)were contrasted... Using mesoscale numerical model WRFV3.7,simulation tests of a low-vortex rainstorm were carried out in Langfang area,and simulation results of three boundary layer parameterization schemes(MYJ,YSU,ACM2)were contrasted.The results showed that the rainstorm in Langfang area had better dynamic condition.By the influence of northeast cold vortex,cold vortex at high altitude cooperated with the surface wind speed convergence,which provided better dynamic condition for strong convective rainfall.Three boundary layer parameterization schemes all simulated surface wind speed convergence of rainstorm center.Simulation results of 24-h rainfall distribution showed that the simulation of YSU scheme was better than ACM2 and MYJ.The simulation results of flow field and temperature field also verified that YSU scheme was better than other schemes. 展开更多
关键词 Boundary layer parameterization scheme WRF model Low-vortex rainstorm
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铁路专用线站场改建方案研究 认领
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作者 姜旭 《黑龙江科学》 2021年第6期104-105,共2页
分析了站场设计原则。以专用铁路站场改建工程为研究对象,结合运量预测及周边地理条件,提出了两种改扩建方案,并分析了各自的优缺点,确定了专用铁路车站改扩建方案。
关键词 铁路专用线 铁路站场 方案
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安全壳过滤排放系统容量确定 认领
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作者 李丽娟 周喆 丁亮 《核科学与工程》 CAS CSCD 北大核心 2021年第1期57-62,共6页
通过研究安全壳过滤排放系统功能、方案、法规标准要求,进行全面、详细的分析计算,包括PCS不可用以及1列PCS可用、不同气体排量等多种假设和工况,综合考量压力控制能力和考虑产品的成熟性,确定安全壳过滤排放系统的排量为4 kg/s(0.52 M... 通过研究安全壳过滤排放系统功能、方案、法规标准要求,进行全面、详细的分析计算,包括PCS不可用以及1列PCS可用、不同气体排量等多种假设和工况,综合考量压力控制能力和考虑产品的成熟性,确定安全壳过滤排放系统的排量为4 kg/s(0.52 MPa)。为安全壳过滤排放系统设计、采购、研发提供输入条件。 展开更多
关键词 安全壳过滤排放系统 方案 法规标准要求 容量确定
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Event-triggered bipartite consensus over cooperation-competition networks under DoS attacks 认领
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作者 HU AiHua PARK J H +2 位作者 CAO JinDe HU ManFeng LUO YiPing 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2021年第1期157-168,共12页
This paper addresses the bipartite consensus over cooperation-competition networks affected by denial-of-service(DoS) attacks.Consider that a network consists of multiple interactive agents, and the relationship betwe... This paper addresses the bipartite consensus over cooperation-competition networks affected by denial-of-service(DoS) attacks.Consider that a network consists of multiple interactive agents, and the relationship between neighboring agents is cooperative or competitive. Meanwhile, information transmission among the agents is unavailable during the intervals of attacks. In order to save communication resources and exclude the Zeno behavior, an event-triggered scheme depending on the sampled-data information from neighboring agents is proposed, and efficient defense strategies in response to the attacks are put forward.Suppose that the frequency and duration of DoS attacks meet certain requirements, then according to the signed graph theory,the La Salle’s invariance principle, and the convergence of monotone sequences, the results of bipartite consensus via the eventtriggered protocol are provided, which are mainly related to the communication topology of the network, the sampling period,and the threshold parameters in the event-triggered scheme. It is shown that the bipartite consensus is realized even though the DoS attacks take place frequently. Furthermore, this paper discusses the bipartite consensus in the presence of DoS attacks with a random unsuccessful rate. Finally, numerical simulations illustrate the theoretical results. 展开更多
关键词 bipartite consensus denial-of-service(DoS)attack event-triggered scheme structural balance multiagent system
赵庄煤矿2#底抽巷围岩稳定性分析及支护技术研究 认领
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作者 谢志强 《山东煤炭科技》 2021年第1期68-71,共4页
以2319工作面底抽巷为研究背景,通过数值模拟与现场实测方法,确定巷道支护效果。研究表明:巷道围岩变形量大小的位置不同及垂直应力分布的情况是影响底抽巷变形破坏的重要因素;采用锚、网、梁、索联合支护方式后,有效地控制了围岩的破坏... 以2319工作面底抽巷为研究背景,通过数值模拟与现场实测方法,确定巷道支护效果。研究表明:巷道围岩变形量大小的位置不同及垂直应力分布的情况是影响底抽巷变形破坏的重要因素;采用锚、网、梁、索联合支护方式后,有效地控制了围岩的破坏,提高了巷道的安全性。 展开更多
关键词 底抽巷 支护 方案
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A HYBRID EXPLICIT-IMPLICIT SCHEME FOR THE TIME-DEPENDENT WIGNER EQUATION 认领
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作者 Haiyan Jiang Tiao Lu Xu Yin 《计算数学:英文版》 SCIE CSCD 2021年第1期22-42,共21页
This paper designs a hybrid scheme based on finite difference methods and a spectral method for the time-dependent Wigner equation,and gives the error analysis for the full discret ization of its initial value problem... This paper designs a hybrid scheme based on finite difference methods and a spectral method for the time-dependent Wigner equation,and gives the error analysis for the full discret ization of its initial value problem.An explicit-implicit time-splitting scheme is used for time integration and the second-order upwind finite difference scheme is used to dis-cretize the advection term.The consistence error and the stability of the full discretization are analyzed.A Fourier spectral method is used to approximate the pseudo-differential operator term and the corresponding error is studied in detail.The final convergence result shows clearly how the regularity of the solution affects the convergence order of the pro-posed scheme.N umerical results are presented for confirming the sharpness of the analysis.The scattering effects of a Gaussian wave packet tunneling through a Gaussian potential barrier are investigated.The evolution of the density function shows that a larger portion of the wave is reflected when the height and the width of the barrier increase.Mathematics subject classification:65M06,65M70. 展开更多
关键词 Finite diference method Spectral method Hybrid scheme Error analysis Wigner equation.
Properties of High-Order Finite Difference Schemes and Idealized Numerical Testing 认领
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作者 Daosheng XU Dehui CHEN Kaixin WU 《大气科学进展:英文版》 SCIE CAS CSCD 2021年第4期615-626,共12页
Construction of high-order difference schemes based on Taylor series expansion has long been a hot topic in computational mathematics, while its application in comprehensive weather models is still very rare. Here, th... Construction of high-order difference schemes based on Taylor series expansion has long been a hot topic in computational mathematics, while its application in comprehensive weather models is still very rare. Here, the properties of high-order finite difference schemes are studied based on idealized numerical testing, for the purpose of their application in the Global/Regional Assimilation and Prediction System(GRAPES) model. It is found that the pros and cons due to grid staggering choices diminish with higher-order schemes based on linearized analysis of the one-dimensional gravity wave equation. The improvement of higher-order difference schemes is still obvious for the mesh with smooth varied grid distance. The results of discontinuous square wave testing also exhibits the superiority of high-order schemes. For a model grid with severe non-uniformity and non-orthogonality, the advantage of high-order difference schemes is inapparent, as shown by the results of two-dimensional idealized advection tests under a terrain-following coordinate. In addition, the increase in computational expense caused by high-order schemes can be avoided by the precondition technique used in the GRAPES model. In general, a high-order finite difference scheme is a preferable choice for the tropical regional GRAPES model with a quasi-uniform and quasi-orthogonal grid mesh. 展开更多
关键词 high-order difference scheme DISPERSION UNIFORM ORTHOGONAL computational efficiency
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南京市某景观湖区防洪规划方案研究 认领
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作者 杨勇 邢少佳 +1 位作者 尹桂平 李结华 《城市道桥与防洪》 2021年第3期94-96,M0012,共4页
随着社会经济的发展,人们对生活环境的要求越来越高。景观水体是钢筋混凝土森林中的一抹绿色,为人们提供了舒适的休闲生活空间。但在景观湖的规划设计中,尚有诸多问题没有得到解决。目前很多文献关注的重点也多是湖体水量补给、水质控... 随着社会经济的发展,人们对生活环境的要求越来越高。景观水体是钢筋混凝土森林中的一抹绿色,为人们提供了舒适的休闲生活空间。但在景观湖的规划设计中,尚有诸多问题没有得到解决。目前很多文献关注的重点也多是湖体水量补给、水质控制等方面,反而最基本的防洪安全往往被忽视。结合实际案例,对南京某景观湖区从防洪规划方面进行研究,并进行水量平衡分析,提出了水质控制建议,可为今后类似工程提供借鉴和参考。 展开更多
关键词 景观湖 防洪 方案
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Discontinuous event-trigger scheme for global stabilization of state-dependent switching neural networks with communication delay 认领
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作者 樊英杰 王震 +1 位作者 夏建伟 沈浩 《中国物理B:英文版》 SCIE EI CAS CSCD 2021年第3期119-128,共10页
This paper is concerned with the global stabilization of state-dependent switching neural networks(SDSNNs)viadiscontinuous event-triggered control with network-induced communication delay.Aiming at decreasing triggeri... This paper is concerned with the global stabilization of state-dependent switching neural networks(SDSNNs)viadiscontinuous event-triggered control with network-induced communication delay.Aiming at decreasing triggering times,a discontinuous event-trigger scheme is utilized to determine whether the sampling information is required to be sent outor not.Meanwhile,under the effect of communication delay,the trigger condition and SDSNNs are transformed into twotractable models by designing a fictitious delay function.Then,using the Lyapunov–Krasovskii stability theory,someinequality estimation techniques,and extended reciprocally convex combination method,two sufficient criteria are established for ensuring the global stabilization of the resulting closed-loop SDSNNs,respectively.A unified framework isderived that has the ability to handle the simultaneous existence of the communication delay,the properties of discontinuousevent-trigger scheme,as well as feedback controller design.Additionally,the developed results demonstrate a quantitativerelationship among the event trigger parameter,communication delay,and triggering times.Finally,two numerical examples are presented to illustrate the usefulness of the developed stabilization scheme. 展开更多
关键词 global stabilization state-dependent switching neural networks discontinuous event-trigger scheme communication delay
A renewable energy forecasting and control approach to secured edge-level efficiency in a distributed micro-grid 认领
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作者 Raphael Anaadumba Qi Liu +3 位作者 Bockarie Daniel Marah Francis Mawuli Nakoty Xiaodong Liu Yonghong Zhang 《Cybersecurity》 CSCD 2021年第1期1-12,共12页
Energy forecasting using Renewable energy sources(RESs)is gradually gaining weight in the research field due to the benefits it presents to the modern-day environment.Not only does energy forecasting using renewable e... Energy forecasting using Renewable energy sources(RESs)is gradually gaining weight in the research field due to the benefits it presents to the modern-day environment.Not only does energy forecasting using renewable energy sources help mitigate the greenhouse effect,it also helps to conserve energy for future use.Over the years,several methods for energy forecasting have been proposed,all of which were more concerned with the accuracy of the prediction models with little or no considerations to the operating environment.This research,however,proposes the uses of Deep Neural Network(DNN)for energy forecasting on mobile devices at the edge of the network.This ensures low latency and communication overhead for all energy forecasting operations since they are carried out at the network periphery.Nevertheless,the cloud would be used as a support for the mobile devices by providing permanent storage for the locally generated data and a platform for offloading resource-intensive computations that exceed the capabilities of the local mobile devices as well as security for them.Electrical network topology was proposed which allows seamless incorporation of multiple RESs into the distributed renewable energy source(DRES)network.Moreover,a novel grid control algorithm that uses the forecasting model to administer a wellcoordinated and effective control for renewable energy sources(RESs)in the electrical network is designed.The electrical network was simulated with two RESs and a DNN model was used to create a forecasting model for the simulated network.The model was trained using a dataset from a solar power generation company in Belgium(elis)and was experimented with a different number of layers to determine the optimum architecture for performing the forecasting operations.The performance of each architecture was evaluated using the mean square error(MSE)and the r-square. 展开更多
关键词 Artificial neural network Distributed microgrid systems Renewable energy source Edge control scheme
LSPR增强0D/2D CdS/MoO3-xS型异质结的构建及其可见光光催化活性研究 认领 被引量:1
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作者 彭进军 沈珺 +3 位作者 于晓慧 唐华 Zulfiqar 刘芹芹 《催化学报》 SCIE EI CAS CSCD 北大核心 2021年第1期87-96,共10页
近年来,等离子体半导体光催化剂因其具有从可见光到近红外光的光响应而引起了人们极大的研究兴趣.含有丰富氧空位的非化学计量的氧化钼(MoO3-x)具有中心位于700 nm和尾部吸收拓展至2000 nm强的局域表面等离子体共振(LSPR)效应,因此,MoO... 近年来,等离子体半导体光催化剂因其具有从可见光到近红外光的光响应而引起了人们极大的研究兴趣.含有丰富氧空位的非化学计量的氧化钼(MoO3-x)具有中心位于700 nm和尾部吸收拓展至2000 nm强的局域表面等离子体共振(LSPR)效应,因此,MoO3-x或将成为实现全光谱响应光催化制氢技术最有吸引力的候选材料之一.然而,单一MoO3-x中电荷载流子的复合快速.具有II型、Z型或S型异质结构的MoO3-x基复合光催化剂的构建被证明是同时实现拓展光吸收和分离光生载流子改善光催化析氢性能的有效策略.与传统的Ⅱ型异质结构相比,Z型或S型可在较高还原电位上进行水分解反应,又可以实现光生载流子的有效分离.相比于Z型,S型由于内部电场导致的半导体的能带玩去可以进一步缩短电子与空穴之间的迁移距离,从而导致光诱导载流子的更快分离.基于此,本文选择了与MoO3-x能带匹配的CdS半导体催化剂,通过简单的共沉淀法在具有LSPR效应的二维(2D)MoO3-x椭圆纳米片上生长零维(0D)CdS纳米粒子,制备了LSPR增强的0D/2D CdS/MoO3-xS型异质结.由于MoO3-x的引入,0D/2D CdS/MoO3-x复合材料展现出了一个因LSPR效应而具有的从600到1400 nm的尾部吸收,并且这种尾部吸收强度随着复合材料中MoO3-x含量的增加而增加.在可见光光催化反应中,CdS/MoO3-x复合材料的产氢速率为7.44 mmol·g^-1·h^-1,为单一CdS的10.3倍.当采用不同波段的单色光作为激发光源,在420,450和550 nm单色光的照射下,CdS/MoO3-x复合材料的产氢效率为15.7,10.9和193.4 mmol·g^-1,分别比CdS高6.8,5.0和3倍.当激发波长拓展至650 nm时,CdS/MoO3-x复合材料的产氢效率为6.83 mmol·g^-1,而CdS则不具有产氢活性,侧面体现了MoO3-x的LSPR效应在提升光解水产氢活性方向的有效作用.我们利用肖特基和固体紫外测试确定了CdS和MoO3-x的能带结构,并通过第一原理密度泛函理论模拟计算了CdS 展开更多
关键词 CDS MoO3-x 光催化产氢 S型 LSPR效应
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具有高效电荷分离的2D/2D α-Fe2O3/Bi2WO6 S型异质结增强光-芬顿催化活性 认领
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作者 王文亮 赵稳立 +2 位作者 张灏纯 窦新城 史海峰 《催化学报》 SCIE EI CAS CSCD 北大核心 2021年第1期97-106,共10页
近年来,Fenton反应由于其成本低,反应速度快,操作简单等优势受到了广泛的研究.传统的均相Fenton反应可通过H2O2氧化Fe2+产生具有强氧化性的羟基自由基,用于处理难降解的有机物.然而,Fenton反应存在两个主要问题,首先,在Fenton反应中需... 近年来,Fenton反应由于其成本低,反应速度快,操作简单等优势受到了广泛的研究.传统的均相Fenton反应可通过H2O2氧化Fe2+产生具有强氧化性的羟基自由基,用于处理难降解的有机物.然而,Fenton反应存在两个主要问题,首先,在Fenton反应中需要加入大量的酸来维持酸性环境,以保证反应的最佳活性.其次,Fenton反应中铁离子不断流失并形成固体污泥,这严重影响了Fenton反应产生•OH的效率.目前,将光催化反应与非均相芬顿反应相结合是改善这些问题的有效方案.非均相光芬顿反应不仅能提高有机物降解的活性,而且通过光催化剂导带上的电子有效减少Fe^3+的浸出和铁氢氧化物沉淀的产生.最近,作为一种可见光Fenton催化剂,α-Fe2O3可以在几乎中性的条件下发生光芬顿反应,这解决了在反应过程中需要随时调整PH值的问题.此外,光照条件下α-Fe2O3价带上的电子能跃迁至导带并将Fe3+还原成Fe^2+,从而减少铁离子的损耗.然而,由于光生载流子复合率较高等问题,单一α-Fe2O3光催化剂的催化活性仍不理想.构建具有2D/2D结构的S型异质结可以缩短电子在界面间的传输距离,增大材料的活性位点,将光生电子-空穴在空间上分离,从而有效增强光生载流子的分离效率.因此,构建2D/2Dα-Fe2O3/Bi2WO6 S型异质结,并用于光芬顿反应有望进一步提高对有机污染物的降解效率.本文通过简易的水热法制备了具有2D/2D结构的α-Fe2O3/Bi2WO6 S型异质结光芬顿催化剂,并通过XRD、BET、TEM、XPS和UV-Vis等手段对催化剂的晶体结构、元素状态、微观结构、光学性质和化学组分进行了表征.通过在可见光照射下降解甲基蓝(MB),考察了α-Fe2O3/Bi2WO6的光芬顿催化活性.结果表明,由于光催化反应与Fenton反应的协同作用,α-Fe2O3/Bi2WO6表现出了明显增强的光-Fenton催化活性,最佳比例的α-Fe2O3/Bi2WO6的活性分别是单一α-Fe2O3和Bi2WO6的11.06倍 展开更多
关键词 Bi2WO6 Α-FE2O3 S型异质结 光芬顿 2D光催化剂
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