检索结果-南通市图书馆

Deep Reinforcement Learning Based Resource Allocation for Fault Detection with Cloud Edge Collaboration in Smart Grid

在线全文

学校读者我要写书评

暂无评论

CSEE Journal of Power and Energy Systems 2024年第3期10卷 1220-1230页

作者： Qiyue Li Yadong Zhu Jinjin Ding Weitao Li Wei Sun lijian Ding Hefei University of Technology Engineering Technology Research Center of Industrial Automation Hefei 230009China Electric Power Research Institute of State Grid Anhui Electric Power Co. Ltd.Hefei 230000China Hefei University of Technology Hefei 230009China IEEE CSEE

Real-time fault detection is important for operation of smart *** has become a trend of future development to design an anomaly detection system based on deep learning by using the powerful computing power of the ***,delay of Internet transmission is large,which may make the delay time of detection and transmission go beyond the ***,the edge-based scheme may not be able to undertake all data detection tasks due to limited computing resources of edge ***,we propose a cloud-edge collaborative smart grid fault detection system,next to which edge devices are placed,and equipped with a lightweight neural network with different precision for fault *** addition,a sub-optimal and realtime communication and computing resource allocation method is proposed based on deep reinforcement *** method greatly speeds up solution time,which can meet the requirements of data transmission delay,maximize the system throughput,and improve communication *** results show the scheme is superior in transmission delay and improves real-time performance of the smart grid detection system.

关键词： Cloud-edge collaboration communication delay deep reinforcement learning fault detection smart grid

The Potential Game-Changer:A Concept-to-Proof Study on D:A Heterojunction-Free Organic Photovoltaics

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第3期42卷 252-258页

作者： lijian Zuo Sae Byeok Jo Xueliang Shi Francis Lin Alex Jen State Key Laboratory of Silicon and Advanced Semiconductor Materials MOE Key Laboratory of Macromolecular Synthesis and FunctionalizationDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhouZhejiang310058 China Department of Materials Science and Engineering University of WashingtonSeattleWAUSA School of Chemical Engineering Sungkyunkwan University (SKKU)Suwon16419 Republic of Korea School of Chemistry and Molecular Engineering East China Normal UniversityShanghai200062 China Department of Materials Science and Engineering City University of Hong KongKowloonHong KongChina Department of Chemistry City University of Hong KongKowloonHong KongChina Hong Kong Institute for Clean Energy Hong KongChina

Since 1986,the donor-acceptor (D:A) heterojunction has been regarded a necessity for high-efficiency organic photovoltaics (OPVs),due to its unique advantage in compensating the intrinsic limitations of organic semiconductors,such as high exciton binding energy and poor ambipolar charge mobility. While this adversely causes tremendous non-radiative charge recombination and instability issues,which currently become the most critical limits for commercialization of OPVs. Here,we present a concept-to-proof study on the potential of D:A heterojunction free OPV by taking advantage of recent progress of non-fullerene acceptors. First,we demonstrate that the “free carriers” can be spontaneously generated upon illumination in an NFA,i.e.,the 6TIC-4F single layer. Second,the 6TIC-4F layer also exhibits good ambipolar charge transporting property. These exceptional characteristics distinguish it from the traditional organic semiconductors,and relieve it from the reliance of D:A heterojunction to independently work as active layer. As a result,the subsequent OPV by simply sandwiching the 6TIC-4F layer between the cathode and anode yields a considerably high power conversion efficiency ~1%. Moreover,we find the D:A heterojunction free device exhibits two order of magnitude higher electroluminescence quantum efficiency and significantly reduced VOC loss by 0.16 eV compared to those of the D:A BHJ structure,validating its promise for higher efficiency in the future. Therefore,our work demonstrates the possibility of using D:A heterojunction-free device structure for high performance,that can potentially become the next game changer of OPV.

关键词： Organic solar cells Spontaneous charge generation Ambipolar charge transport Charge recombination Perovskite-like organic semiconductor Schottky-junction structure Single component

A Numerical Study on the Effect of the Backflow Hole Position on the Performances of a Self-Priming Pump

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Fluid Dynamics & Materials Processing 2024年第5期20卷 1103-1122页

作者： Dongwei Wang lijian Cao Weidong Wang Jiajun Hu School of Energy and Power Engineering Lanzhou University of TechnologyLanzhou730050China Sanlian Pump Industry Co. Ltd.Ma’anshan243000China

A self-priming pump is a centrifugal pump that has the ability to prime itself. Typically, its performance dependson the configuration of its reflux hole. In this study, the ANSYS FLUENT software is used to investigate the effectsof three different radial positions of the reflux hole on gas-liquid two-phase distribution, pressure pulsation, andimp during self-priming. The research results indicate that: (1) The effective channel size for the reflux liquid toenter the volute varies depending on the location of the reflux hole. The effect of the impeller rotation on thereflux liquid becomes more obvious as the setting distance of the reflux aperture decreases. (2) The position ofthe reflux hole significantly affects the gas phase mass fraction inside the impeller, resulting in a significant reductionin the time it takes for the mass fraction to exceed 80%. (3) The position of the reflux hole significantly affectsthe average pressure on each monitoring surface. (4) Placing the reflux hole at a excessively distant radial distancecan result in an excessive vertical component. (5) The self-priming performance of the pump can be improved tosome extent by placing the return hole at a small radial distance.

关键词： Self-priming pump self-priming time numerical calculation gas-liquid two-phase flow

Laser ablation mechanism and performance of glass fiber-reinforced phenolic composites:An experimental study and dual-scale modelling

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第8期37卷 470-485页

作者： Ran BI Pengfei SHEN Longyu ZHU Zhengzheng MA Chuyang LUO Yongfeng LI lijian PAN Shanghai Key Laboratory of Lightweight Composite Donghua UniversityShanghai 201620China Shanghai High Performance Fibers and Composites Center(Province-Ministry Joint) Center for Civil Aviation CompositesDonghua UniversityShanghai 201620China AVIC Composite Corporation Ltd Beijing 101300China

Both experimental and simulation approaches were employed to investigate the laser ablation mechanism and performances of Glass Fiber Reinforced Phenolic Composites(GFRP).During the ablation process,the difference in thermal conductivities of the glass fibers and the resin matrix as well as their discrepant physical and chemical reactions form a conical ablation *** formation of a residual carbon layer effectively mitigates the ablation rate in the thickness direction.A higher power density results in a faster ablation rate,while a longer irradiation time leads to a larger ablation pit *** account for the variation in thermal conductivity between the fiber and resin,a macro-mesoscale model was developed to differentiate the matrix from the fiber *** element analysis revealed that laser irradiation leads to phenolic decomposition,glass fiber melting vaporization,and residual carbon skeleton *** dual-scale model exhibits precise prediction capabilities concerning the laser ablation process of GFRP,and its accuracy is confirmed through the comparison of simulation and experimental results for the GFRP laser ablation *** model provides a feasible method for performance evaluation and lifetime prediction of GFRP subjected to continuous wave laser irradiation.

关键词： Polymer-matrix composites Continuous-wave laser Microstructural analysis Ablation mechanism Finite element method

Unveiling the time-temperature dependence of metastability of supercooled liquid using nano-calorimetry

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 119-127页

作者： Yijun Ding lijian Song Zheng Wang Ruiqi Yu Junqiang Wang Lina Hu Yuanzheng Yue Edgar D.Zanotto Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong University Jinan 250061China Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201China Key Laboratory of Experimental Teratology Shandong University Jinan 250061 China Department of Chemistry and Bioscience Aalborg UniversityAalborg 9220Denmark Department of Materials Engineering Federal University of Sao CarlosSao Carlos SP 13.565-905Brazil

There is a lack of understanding of both the conversion of an unstable glass into a metastable supercooled liquid(MSL) upon heating and the metastability of MSLs. In this study, we investigated the time-and temperature-dependent metastability of an MSL using an advanced nano-calorimetric technique. The chosen Au-based metallic glass(Au MG) allowed adequate probing of its MSL in a temperature range between 10 and 70 K above the standard glass transition temperature. We found that the survival time of the MSL state is a quadratic function of temperature. Beyond this duration threshold, the sample undergoes fast crystallization even if it is below the crystallization temperature that is measured using differential scanning *** transmission electron microscopy, we observed the formation of clusters with a partially ordered lattice structure during relaxation in the Au MG sample fabricated using a nano-calorimeter. The atomic ordering within the clusters was enhanced by increasing time and temperature in the MSL region. Once the as-produced glass entered the MSL stage upon heating followed by a quenching stage at a given rate, the mechanical properties of the quenched glass remained the same regardless of its holding temperature and duration within the MSL region. This work provides insights into the glass-MSL-crystal transformation and offers guidance for designing standard metallic glasses for property characterizations.

关键词： metallic glass supercooled liquid relaxation nucleation nano calorimetric technology

在线全文

学校读者我要写书评

暂无评论

光量子精密测量研究进展(特邀)

中国激光 2024年第1期51卷 354-368页

作者：王犇张利剑南京大学现代工程与应用科学学院江苏南京210023 智能光传感与调控技术教育部重点实验室江苏南京210023 人工微结构科学与技术协同创新中心江苏南京210023 南京大学固体微结构物理国家重点实验室江苏南京210023

量子精密测量作为当代量子力学的主要应用方面之一,近些年来一直是量子科技的重要研究和发展方向。量子精密测量的主要研究目标是针对物理系统中的未知参数,利用量子资源进行量子增强测量,以提升参数测量精度。与其他物理系统相比,光子... 详细信息

量子精密测量作为当代量子力学的主要应用方面之一,近些年来一直是量子科技的重要研究和发展方向。量子精密测量的主要研究目标是针对物理系统中的未知参数,利用量子资源进行量子增强测量,以提升参数测量精度。与其他物理系统相比,光子系统具有相干时间长、不易受到环境干扰等优越性,因而常被用作量子信息处理的载体。以光子为基础的传感器提升传感精度是光量子精密测量的主要任务。介绍了量子精密测量的一般性原理,给出参数估计的量子极限精度下界。同时,介绍了目前光量子精密测量的理论与实验研究进展以及相应的挑战。

关键词：量子光学量子精密测量参数估计海森堡极限传感

走向“他者”的比较文学——评苏源熙《“制造”野蛮人:中国文学和多语亚洲》

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国比较文学 2024年第3期 280-284页

作者：王礼健上海师范大学人文学院安庆师范大学

自上世纪60年代以来,关于比较文学学科建制的“危机说”“死亡说”不绝于耳。在此背景下,斯皮瓦克(Gayatri Spivak)在《一门学科之死》(Death of a Discipline, 2003)中呼吁一种“走向他者”的、新的比较文学,即与区域研究携手,关注世... 详细信息

自上世纪60年代以来,关于比较文学学科建制的“危机说”“死亡说”不绝于耳。在此背景下,斯皮瓦克(Gayatri Spivak)在《一门学科之死》(Death of a Discipline, 2003)中呼吁一种“走向他者”的、新的比较文学,即与区域研究携手,关注世界无数本土语言和习语、连接人文学科和社会学科,同时属于南半球的、新的比较文学。

关键词：本土语言社会学科斯皮瓦克比较文学人文学科习语他者

基于倾斜滑裂面假设的浅埋盾构隧道松动土压力研究

在线全文

学校读者我要写书评

暂无评论

中国铁道科学 2024年第3期45卷 97-106页

作者：梁连方焘方立建华东交通大学土木建筑学院江西南昌330013 福州大学土木工程学院福建福州350108

随着地铁建设的快速发展,隧道上方松动土压力的计算成了隧道工程领域的研究热点,而隧道松动区的确定对松动土压力的计算至关重要。为简便而准确地确定松动区的范围,首先假设松动区的边界为倾斜直线,然后基于Mohr-Coulomb破坏准则并考虑... 详细信息

随着地铁建设的快速发展,隧道上方松动土压力的计算成了隧道工程领域的研究热点,而隧道松动区的确定对松动土压力的计算至关重要。为简便而准确地确定松动区的范围,首先假设松动区的边界为倾斜直线,然后基于Mohr-Coulomb破坏准则并考虑隧道尺寸、埋深等因素的影响推导滑裂角计算式,进而确定隧道周围地层的松动区范围。最后结合松动区土体主应力轴旋转理论以及倾斜滑裂面的假设,推导出滑裂面上的侧压力系数以及隧道松动土压力的计算式。结果表明:滑裂角随土体内摩擦角的增大而增大,随隧道埋深比的增大先减小然后趋于稳定;大主应力轨迹线为圆弧时计算更为简便、更易推广,可采用圆弧形大主应力轨迹的假设计算隧道松动土压力;松动土压力计算式所得结果和实际的试验结果吻合较好,因此该计算式可应用于砂土地质条件下浅埋盾构隧道上方的松动土压力计算。

关键词：隧道工程松动区土压力土拱效应滑裂面数值模拟

Perovskite solar cells with ferroelectricity

在线全文

学校读者我要写书评

暂无评论

Information ＆ Functional Materials 2024年第1期1卷 87-107页

作者： Tie Zhang Huiming Luo Mojtaba Abdi‐Jalebi Hongzheng Chen lijian Zuo State Key Laboratory of Silicon and Advanced Semiconductor Materials Department of Polymer Science and EngineeringZhejiang UniversityHangzhouChina Zhejiang University‐Hangzhou Global Scientific and Technological Innovation Center HangzhouChina Institute for Materials Discovery University College LondonLondonUK

Halide perovskites show excellent optoelectronic properties for solar cell ***,perovskite crystalline structures have been widely re-ported to deliver superior ferroelectric *** a result,the integration of the ferroelectric process with the photon‐to‐electron energy conversion process becomes feasible to generate interesting photo‐physical properties and further boost the device performance of perovskite solar cells(PSCs),which have started to attract more and more attention in recent ***,we have reviewed the recent progress in PSCs with ferroelectricity(FE‐PSCs),by classifying them into three regimes according to the degree of phase segre-gation,for example,the layer‐structured ferroelectric/halide perovskite com-posite,micro phase‐separated ferroelectric/halide perovskite composite,and the intrinsic ferroelectric halide perovskite *** different composite structures enable a large range of interesting optoelectronic properties and the specific structure significantly enhances the device performance of *** most prominent contribution of ferroelectricity is that it can provide an extra electrical field to drive charge generation,transport,and ***,key challenges and opportunities of the integration of ferroelectricity with photo-voltaics are *** hope our work can draw intensive attention in this field to accelerate the establishment of the basic theories in ferroelectricity and the commercialization of PSCs.

关键词： built‐in potential carrier dynamics dipole moments ferroelectricity perovskite solar cells