检索结果-南通市图书馆

A cumulative damage model for predicting and assessing raveling in asphalt pavement using an energy dissipation approach

在线全文

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2024年第6期18卷 949-962页

作者： Kailing DEng Duanyi WAng cheng TAng Jianwen SITU Luobin chen School of Civil Engineering and Transportation South China University of TechnologyGuangzhou 510640China

Raveling is a common distress of asphalt pavements,defined as the removal of stones from the pavement *** predict and assess raveling quantitatively,a cumulative damage model based on an energy dissipation approach has been developed at the meso *** construct the model,a new test method,the pendulum impact test,was employed to determine the fracture energy of the stone-mastic-stone meso-unit,while digital image analysis and dynamic shear rheometer test were used to acquire the strain rate of specimens and the rheology property of mastic,*** of the model reveals that when the material properties remain constant,the cumulative damage is directly correlated with loading time,loading amplitude,and loading ***,damage increases with superimposed linear and cosine variations over time.A higher stress amplitude results in a more rapidly increasing rate of damage,while a lower load frequency leads to more severe damage within the same loading ***,an example of the application of the model has been presented,showing that the model can be utilized to estimate failure life due to *** model is able to offer a theoretical foundation for the design and maintenance of anti-raveling asphalt pavements.

关键词： asphalt pavement raveling cumulative damage dissipation energy theory

Aero-structural design of joined-wing aircraft based on high-fidelity model

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4期37卷 363-377页

作者： cheng HE Fengjiang ZHAN Luchuang mA Gang chen Jianying mA Unmanned Air Vehicle Research Institute Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Advanced Technology for Small and medium-sized UAV Ministry of Industry and Information TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China Aerospace System Engineering Shanghai Shanghai 201108China

The joined-wing configuration reduces induced drag and structural weight by connecting the rear wing to the front *** addition,the rear wing can replace the role of the horizontal tail of a conventional aircraft,thus eliminating the aerodynamic drag and weight associated with the horizontal *** particular shape creates a highly coupled relationship between aerodynamics and structure,which must be fully considered during the overall design process to enhance aircraft *** this research,an aero-structural design model of the joined-wing aircraft is constructed based on high-fidelity computational fluid dynamics and structural finite element *** model is able to obtain accurate aerodynamic loads for the non-planar wing and to simulate the statically indeterminate structure of the closed wing *** influence of the joined-wing shape parameters on the aerodynamic and structural disciplines,as well as the influence of geometric nonlinear characteristics,deformation constraints and buckling constraints on the structural weight are all taken into *** model is applied to complete the aero-structural design optimization of a high-altitude long-endurance joined-wing aircraft,and wind tunnel tests are *** test results verify the credibility of the design model proposed and the validity of the design environment.

关键词： Joined-wing configuration Aircraft design Aero-structural design Finite element Wind tunnel test

Electrothermal model Based Remaining Charging Time Prediction of Lithium-Ion Batteries against Wide Temperature Range

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of mechanical Engineering 2024年第2期37卷 330-339页

作者： Rui Xiong Zian Zhao cheng chen Xinggang Li Weixiang Shen School of mechanical Engineering Beijing Institute of TechnologyBeijing 100081China School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyHawthornVIC 3122Australia

Battery remaining charging time(RCT)prediction can facilitate charging management and alleviate mileage anxiety for electric vehicles(EVs).Also,it is of great significance to improve EV users’***,the RCT for a lithiumion battery pack in EVs changes with temperature and other battery *** study proposes an electrothermal model-based method to accurately predict battery ***,a characteristic battery cell is adopted to represent the battery pack,thus an equivalent circuit model(ECm)of the characteristic battery cell is established to describe the electrical behaviors of a battery ***,an equivalent thermal model(ETm)of the battery pack is developed by considering the influence of ambient temperature,thermal management,and battery connectors in the battery pack to calculate the temperature which is then fed back to the ECm to realize electrothermal ***,the RCT prediction method is proposed based on the electrothermal model and validated in the wide temperature range from-20℃to 45℃.The experimental results show that the prediction error of the RCT in the whole temperature range is less than 1.5%.

关键词： Electric vehicles Lithium-ion batteries Remaining charging time Electrothermal model

Cascaded four-wave mixing all-optical wavelength converter based on highly nonlinear fiber deposited graphene oxide

在线全文

学校读者我要写书评

暂无评论

Journal of materials Science & Technology 2024年第4期171卷 10-15页

作者： Yuanhongliu Gao Xiaoyu chen Tonglei cheng Fang Wang Xin Yan College of Information Science and Engineering State Key Laboratory of Synthetical Automation for Process IndustriesNortheastern UniversityShenyang 110819China

The all-optical wavelength conversion using cascaded four-wave mixing(FWm)phenomena with graphene oxide(GO)and a highly nonlinear fiber(HNLF)device is demonstrated *** has a strong third-order nonlinear effect and is an excellent nonlinear optical material for nonlinear optical wavelength *** group velocity matching of pump and signal,HNLF,and GO amplification promote the cascaded nonlinear frequency mixing *** the experimental and analytical results,the maximum spacing between signal and pump is 21 nm,and specifically,the order of cascaded FWm light increases from order 1 to order 2 with increasing GO,and the first-order FWm conversion effi-ciency increases to a maximum of−14.5 *** the best of our knowledge,this is the first time that cascaded FWm-based all-optical wavelength conversion in HNLF-GO with wide wavelength selectivity is investigated with combined pump and signal *** findings not only provide an effective method for achieving all-optical wavelength conversion in cascaded FWm but also offer the possibility of fabricating high-performance nonlinear optical devices.

关键词： Four-wave mixing Graphene oxide Highly nonlinear fiber Optical wavelength conversion

Thermal decomposition mechanism and kinetics of bastnaesite in suspension roasting process:A comparative study in N_(2) and air atmospheres

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第9期42卷 1809-1816,I0006页

作者： Wenbo Li Jijia chen Shaokai cheng Junyan Sun Xiaolong Zhang School of Resources and Civil Engineering Northeastern UniversityShenyang110819China National-Local Joint Engineering Research Center of High-Efficient Exploitation Technology for Refractory Iron Ore Resources Shenyang110819China

To investigate the thermal decomposition behavior and reaction kinetics of bastnaesite in suspension roasting,the gas and solid products of bastnaesite roasted in N2 and air atmospheres were examined using a gas analyzer,X-ray diffraction(XRD),scanning electron microscopy(SEm),and energy dispersive spectrometry(EDS).Subsequently,the kinetic parameters of bastnaesite in the suspension roasting process were derived and calculated using the isothermal *** results show that the decomposition product of bastnaesite in N_(2) is ***,once the roasting temperature exceeds 600℃,CO is generated in addition to CO_(2),and all the XRD diffraction peaks of CeOF are shifted to the right,indicating that CO_(2) can oxidize CeOF and lead to the transformation of Ce(Ⅲ) into Ce(Ⅳ).When roasted in air,the decomposition product CeOF can be completely converted to CeF3 and Ce_(7)O_(12) as it easily ***,the reaction rate of bastnaesite in air is higher than that of N_(2),and the starting reaction temperature is lower than that of N_(2).A large number of irregular cracks and holes appear on the surface of solid-phase products following suspension roasting,which are due to the thermal decomposition of bastnaesite that produces CO_(2) as well as the reconstruction of the lattice of the solid-phase *** reaction kinetic model of bastnaesite roasted in N_(2)(temperature range 600-750℃) and air(temperatu re range 500-575℃) confo rms to the A_(3/2) model with the mechanism function G(α)=-ln(1-α)^(2/3),and the reaction activation energy is 59.78 kj/mol and lnA is 1.65 s^(-1) in N_(2) *** air,the reaction activation energy is 100.30 kj/mol and lnA is 9.63 s^(-1).

关键词： Rare earths Bastnaesite Suspension roasting Thermal decomposition mechanism Reaction kinetics

An Interactive Collaborative Creation System for Shadow Puppets Based on Smooth Generative Adversarial Networks

在线全文

学校读者我要写书评

暂无评论

Computers, materials & Continua 2024年第6期79卷 4107-4126页

作者： cheng Yang miaojia Lou Xiaoyu chen Zixuan Ren Department of Industrial Design Hangzhou City UniversityHangzhou310000China College of Computer Science and Technology Zhejiang UniversityHangzhou310000China

Chinese shadow puppetry has been recognized as a world intangible cultural ***,it faces substantial challenges in its preservation and advancement due to the intricate and labor-intensive nature of crafting shadow *** ensure the inheritance and development of this cultural heritage,it is imperative to enable traditional art to flourish in the digital *** paper presents an Interactive Collaborative Creation System for shadow puppets,designed to facilitate the creation of high-quality shadow puppet images with greater *** system comprises four key functions:Image contour extraction,intelligent reference recommendation,generation network,and color adjustment,all aimed at assisting users in various aspects of the creative process,including drawing,inspiration,and content ***,we propose an enhanced algorithm called Smooth Generative Adversarial Networks(SmoothGAN),which exhibits more stable gradient training and a greater capacity for generating high-resolution shadow puppet ***,we have built a new dataset comprising high-quality shadow puppet images to train the shadow puppet generation *** qualitative and quantitative experimental results demonstrate that SmoothGAN significantly improves the quality of image generation,while our system efficiently assists users in creating high-quality shadow puppet images,with a SUS scale score of *** study provides a valuable theoretical and practical reference for the digital creation of shadow puppet art.

关键词： Shadow puppets deep learning image generation co-create

HEN:a novel hybrid explainable neural network based framework for robust network intrusion detection

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(Information Sciences) 2024年第7期67卷 72-90页

作者： Wei WEI Sijin chen Cen chen Heshi WAng Jing LIU Zhongyao cheng Xiaofeng ZOU School of Computer Science and Engineering Xi'an University of TechnologyShaanxi Key Laboratory for Network Computing and Security Technology School of Computer Science and Technology Wuhan University of Science and Technology School of Future Technology South China University of Technology Shenzhen Research Institute of Hunan University School of Computer Science Hunan University of Technology and Business Institute for Infocomm Research (I2R) Agency for Science Technology and Reseach (A*STAR)

With the rapid development of network technology and the automation process for 5G, cyberattacks have become increasingly complex and threatening. In response to these threats, researchers have developed various network intrusion detection systems(NIDS) to monitor network traffic. However, the incessant emergence of new attack techniques and the lack of system interpretability pose challenges to improving the detection performance of NIDS. To address these issues, this paper proposes a hybrid explainable neural network-based framework that improves both the interpretability of our model and the performance in detecting new attacks through the innovative application of the explainable artificial intelligence(XAI)method. We effectively introduce the Shapley additive explanations(SHAP) method to explain a light gradient boosting machine(Light GBm) model. Additionally, we propose an autoencoder long-term short-term memory(AE-LSTm) network to reconstruct SHAP values previously generated. Furthermore, we define a threshold based on reconstruction errors observed during the training phase. Any network flow that surpasses the specified threshold is classified as an attack flow. This approach enhances the framework's ability to accurately identify attacks. We achieve an accuracy of 92.65%, a recall of 95.26%, a precision of 92.57%,and an F1-score of 93.90% on the dataset NSL-KDD. Experimental results demonstrate that our approach generates detection performance on par with state-of-the-art methods.

关键词： explainable artificial intelligence light gradient boosting machine machine learning network intrusion detection Shapley additive explanation hybrid explainable neural network (HEN)

Parameter selection for the hydroconversion of waste polyethylene plastic under mild conditions: A comprehensive evaluation

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2024年第8期67卷 2413-2426页

作者： cheng LeiLei chen RuiZhe ZHU WeiQiang TIAN ShaoNan GU Jing YUAN HaoRan chen Yong Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640China School of Energy Science and Engineering University of Science and Technology of ChinaHefei 230026China Institute of Process Engineering Chinese Academy of SciencesBeijing 100190China

The hydrogenolysis/hydrocracking of waste polyethylene(PE) has recently been intensively studied, with the general pursuit of low-temperature reaction conditions, increased oil-phase yield, and narrower carbon chain distribution. Before this, we utilized a ball-milled ZSm-22 catalyst loaded with Ru nanoparticles(NPs), which exhibited excellent hydroconversion performance. It deconstructed PE into >80 wt.% oil products under low temperatures and short reaction times. Herein, we investigated the influence of varying temperature/pressure parameters on the degree of specific hydrocracking/internal hydrogenolysis/terminal hydrogenolysis reactions. From the comprehensive energy efficiency perspective, including stirring, reaction, and product separation, as well as taking into account the degree of product isomerization and catalyst lifespan, we analyzed the optimization of parameters. This research abandons the notion that lower temperatures are better and proposes a more comprehensive evaluation framework for low-consumption hydroconversion of PE to produce high-value products.

关键词： plastic upcycling polyethylene hydrocracking hydrogenolysis comprehensive energy efficiency

Top Five Stories of the Cellular Landscape and Therapies of Atherosclerosis:Current Knowledge and Future Perspectives

在线全文

学校读者我要写书评

暂无评论

Current medical Science 2024年第1期44卷 1-27页

作者： Qi PAN cheng chen Yue-jin YAng State Key Laboratory of Cardiovascular Disease Department of CardiologyFuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Science and Peking Union Medical CollegeBeijing 100037China

Atherosclerosis(AS)is characterized by impairment and apoptosis of endothelial cells,continuous systemic and focal inflammation and dysfunction of vascular smooth muscle cells,which is documented as the traditional cellular ***,the mechanisms appear much more complicated than we thought since a bulk of studies on efferocytosis,transdifferentiation and novel cell death forms such as ferroptosis,pyroptosis,and extracellular trap were *** of novel pathological cellular landscapes provides a large number of therapeutic *** the other side,the unsatisfactory therapeutic effects of current treatment with lipid-lowering drugs as the cornerstone also restricts the efforts to reduce global AS *** cell-or nanoparticle-based strategies spurred a lot of attention due to the attractive therapeutic effects and minimized adverse *** the complexity of pathological changes of AS,attempts to develop an almighty medicine based on single mechanisms could be theoretically *** this review,the top stories in the cellular landscapes during the initiation and progression of AS and the therapies were summarized in an integrated perspective to facilitate efforts to develop a multi-targets strategy and fill the gap between mechanism research and clinical *** future challenges and improvements were also discussed.

关键词： atherosclerosis transdifferentiation extracellular traps efferocytosis stem cell nanoparticles