期刊文献+
共找到12篇文章
< 1 >
每页显示 20 50 100
A New Self-assembly Metal CMG Discriminator by Multi-exposure LiGA Like Process and Sacrificial Layer Process 被引量:1
1
作者 张卫平 陈文元 +2 位作者 赵小林 丁桂甫 李胜勇 《Journal of Donghua University(English Edition)》 EI CAS 2005年第4期91-93,共3页
The counter-meshing gears (CMG) discriminator is a mechanically coded lock, which is used to prevent the occurrence of High Consequence Events. This paper advanced a new kind of self-assembly metal CMG discriminator... The counter-meshing gears (CMG) discriminator is a mechanically coded lock, which is used to prevent the occurrence of High Consequence Events. This paper advanced a new kind of self-assembly metal CMG discriminator based on multi-exposure LiGA like process and sacrificial layer process. The new CMG discriminator has the following characters except low cost: 1) it has only discrimination teeth sections; 2) the thickness of each gear layer exceeds one hundred micrometers; 3) it is axially driven by a separate dectronic magnetic micromotor directly; 4) its CMG is made of metal and is batch fabricated in the assembled state; 5) it is prevented from rotating in the opposite direction by pawl/ratchet wheel mechanism; 6) it has simpler structure. This device has better strength and reliability in abnormal environment compared to the existing surface micro machining (SMM) discriminator. 展开更多
关键词 Counter-meshing gears (CMG) discriminator multi-exposure LiGA like process sacrificial layer process.
下载PDF
Numerical Study on Dry Deposition Processes in Canopy Layer
2
作者 雷孝恩 Julius S.Chang 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1992年第4期491-500,共10页
A coupling model between the canopy layer(CL) and atmospheric boundary layer (ABL) for the study of dry deposition velocity is developed. The model consists of six parts: chemical species conservation equation includi... A coupling model between the canopy layer(CL) and atmospheric boundary layer (ABL) for the study of dry deposition velocity is developed. The model consists of six parts: chemical species conservation equation including absorptive factor; the species uptake action including detailed vertical variation of absorptive element in CL; momentum exchange in CL which is represented by a first-order closure momentum equation with an additional larger-scale diffusive term; momentum exchange in ABL which is described by a complete set of the ABL turbulent statistic parameters; absorptivity (or solubility or reflection) at the surface including effects of the physical and chemical characters of the species, land type, seasonal and diurnal variations of the meteorological variables; and deposition velocity derived by distributions of the species with height in CL. Variational rules of the concentration and deposition velocity with both height and time are simulated with the model for both corn and forest canopies. Results predicted with the bulk deposition velocity derived in the paper consist well with experimental data. 展开更多
关键词 Numerical Study on Dry Deposition Processes in Canopy layer
下载PDF
A Novel Intrusion Detection Model of Unknown Attacks Using Convolutional Neural Networks
3
作者 Abdullah Alsaleh 《Computer Systems Science & Engineering》 2024年第2期431-449,共19页
With the increasing number of connected devices in the Internet of Things(IoT)era,the number of intrusions is also increasing.An intrusion detection system(IDS)is a secondary intelligent system for monitoring,detectin... With the increasing number of connected devices in the Internet of Things(IoT)era,the number of intrusions is also increasing.An intrusion detection system(IDS)is a secondary intelligent system for monitoring,detecting and alerting against malicious activity.IDS is important in developing advanced security models.This study reviews the importance of various techniques,tools,and methods used in IoT detection and/or prevention systems.Specifically,it focuses on machine learning(ML)and deep learning(DL)techniques for IDS.This paper proposes an accurate intrusion detection model to detect traditional and new attacks on the Internet of Vehicles.To speed up the detection of recent attacks,the proposed network architecture developed at the data processing layer is incorporated with a convolutional neural network(CNN),which performs better than a support vector machine(SVM).Processing data are enhanced using the synthetic minority oversampling technique to ensure learning accuracy.The nearest class mean classifier is applied during the testing phase to identify new attacks.Experimental results using the AWID dataset,which is one of the most common open intrusion detection datasets,revealed a higher detection accuracy(94%)compared to SVM and random forest methods. 展开更多
关键词 Internet of Vehicles intrusion detection machine learning unknown attacks data processing layer
下载PDF
V-BLAST BASED LDPC-CODED RELAY COOPERATION 被引量:1
4
作者 唐蕾 仰枫帆 +1 位作者 张顺外 范立行 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2013年第4期374-382,共9页
An efficient LDPC-coded multi-relay cooperation architecture is proposed based on virtual vertical Bell Labs layered space-time (V-BLAST) processing for uplink communication, where minimum-mean-square-error (MMSE)... An efficient LDPC-coded multi-relay cooperation architecture is proposed based on virtual vertical Bell Labs layered space-time (V-BLAST) processing for uplink communication, where minimum-mean-square-error (MMSE) and BP-based joint iterative decoding based on the introduced muhi-layer Tanner graph are effectively de- signed to detect and decode the corrupted received sequence at the destination. By introducing V-BLAST transmis- sion to the coded multi-relay cooperation, relays send their streams of symbols simultaneously, which increases the data rate and significantly reduces the transmission delay. The theoretical analysis and numerical results show that the new LDPC coded cooperation scheme outperforms the coded non-cooperation under the same code rate, and it also achieves a good trade-off among the performance, signal delay, and the encoding complexity associated with the number of relays. The performance gain can be credited to the proposed V-BLAST processing architecture and BP-based joint iterative decoding by the introduced multi-layer Tanner graph at a receiver-side. 展开更多
关键词 coded multi-relay cooperation vertical Bell Labs layered space-time processing (V-BLAST) mini-mum-mean-square-error detector~ joint decoding multi-layer Tanner graph
下载PDF
Characterization of cake layer structure on the microfiltration membrane permeability by iron pre-coagulation 被引量:2
5
作者 Jin Wang Siru Pan Dongping Luo 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第2期308-315,共8页
A cake layer is formed by coagulation aggregates under certain transmembrane pressure in the coagulation-microfiltration (MF) process. The characteristics of humic acid aggregates coagulated by different iron-based ... A cake layer is formed by coagulation aggregates under certain transmembrane pressure in the coagulation-microfiltration (MF) process. The characteristics of humic acid aggregates coagulated by different iron-based coagulants, such as charge, size, fractal dimension and compressibility, have an effect on the cake layer structure. At the optimum iron dose of 0.6 to 0.8 mmol/L for ferric chloride (FC) and polymer ferric sulfate (PFS) pre-coagulation, at the point of charge neutralization for near zero zeta potential, the aggregate particles produced possess the greatest size and highest fractal dimension, which contributes to the cake layer being most loose with high porosity and low compressibility. Thus the membrane filterability is better. At a low or high iron dose of FC and PFS, a high negative or positive zeta potential with high charge repulsion results in so many small aggregate particles and low fractal dimension that the cake layer is compact with low porosity and high compressibility. Therefore the membrane fouling is accelerated and MF permeability becomes worse. The variation of cake layer structure as measured by scanning electric microscopy corresponds with the fact that the smaller the coagulation flocs size and fractal dimension are, the lower the porosity and the tighter the cake layer conformation. This also explains the MF membrane flux variation visually and accurately. 展开更多
关键词 coagulation-microfiltration process cake layer structure iron-based coagulant zeta potential porosity scanning electric microscope
原文传递
Advances in scalable gas-phase manufacturing and processing of nanostructured solids: A review 被引量:3
6
作者 Samir Salameh Jesus Gomez-Hernandez +2 位作者 Aristeidis Goulas Hao Van Bui J. Ruud van Ommen 《Particuology》 SCIE EI CAS CSCD 2017年第1期15-39,共25页
Although the gas-phase production of nanostructured solids has already been carried out in industry for decades, only in recentyears has research interest in this topic begun to increase. Nevertheless, despite the rem... Although the gas-phase production of nanostructured solids has already been carried out in industry for decades, only in recentyears has research interest in this topic begun to increase. Nevertheless, despite the remarkable scientific progress made recently, many long-established processes are still used in industry. Scientific advancements can potentially lead to the improvement of existing industrial processes, but also to the development of completely new routes. This paper aims to review state-of-the-art synthesis and processing technologies, as well as the recent developments in academic research. Flame reactors that produce inorganic nanoparticles on industrial- and lab-scales are described, alongside a detailed overview of the different systems used for the production of carbon nanotubes and graphene. We discuss the problems of agglomeration and mixing of nanoparticles, which are strongly related to synthesis and processing. Finally, we focus on two promising processing techniques, namely nanoparticle fluidization and atomic layer deposition. 展开更多
关键词 Nanoparticle synthesis Gas-phase process Nanoparticle fluidization Atomic layer deposition Agglomeration
原文传递
Electron transport layer driven to improve the open-circuit voltage of CH_3NH_3PbI_3 planar perovskite solar cells 被引量:1
7
作者 姚鑫 梁俊辉 +7 位作者 李天天 范琳 石标 魏长春 丁毅 李跃龙 赵颖 张晓丹 《Science China Materials》 SCIE EI CSCD 2018年第1期65-72,共8页
Suitable electron transport layers are essential for high performance planar perovskite heterojunction solar cells. Here, we use ZnO electron transport layer sputtered under oxygen-rich atmosphere at room temperature ... Suitable electron transport layers are essential for high performance planar perovskite heterojunction solar cells. Here, we use ZnO electron transport layer sputtered under oxygen-rich atmosphere at room temperature to decrease the hydroxide and then suppress decomposition of perovskite films. The perovskite films with improved crystallinity and morphology are achieved. Besides, on the ZnO substrate fabricated at oxygen-rich atmosphere, open-circuit voltage of the CH_3NH_3PbI_3-based perovskite solar cells increased by 0.13 V.A high open-circuit voltage of 1.16 V provides a good prospect for the perovskite-based tandem solar cells. The ZnO sputtered at room temperature can be easily fabricated industrially on a large scale, therefore, compatible to flexible and tandem devices. Those properties make the sputtered ZnO films promising as electron transport materials for perovskite solar cells. 展开更多
关键词 planar perovskite solar cells electron transport layer hydroxide suppressed decomposition process enhanced crystallization and morphology
原文传递
STAGNANT LAYER EFFECT IN CVD PROCESS
8
作者 王其闵 章熙康 顾隆道 《Science China Chemistry》 SCIE EI CAS 1986年第4期353-363,共11页
It is clearly shown that the stagnant layer effect is present in entire temperature range in CVD process by pyrolysis of silane. The Curves in logarithmic growth rate vs reciprocal temperature plot can be divided into... It is clearly shown that the stagnant layer effect is present in entire temperature range in CVD process by pyrolysis of silane. The Curves in logarithmic growth rate vs reciprocal temperature plot can be divided into three straight line ranges. In high temperature region the rate-controlling mechanism is the diffusion of silicon atoms, but not of silane, which pass through the stagnant layer after thermal decomposition of silane. In intermediate and low temperature region the growth rate-controlling factor is the decomposition rate of silane in the stagnant layer, but not the surface reaction process. Owing to the difference in ratecontrolling mechanism the growth rate has different dependences on the height of stagnant layer. In intermediate and low temperature region the growth rate is proportional to the stagnant layer height, but in high temperature region it is inversely proportional to the square of the stagnant layer height. 展开更多
关键词 STAGNANT layer EFFECT IN CVD PROCESS RATE CVD
原文传递
Efficient perovskite solar cells based on the novel low-temperature processed electron transport layer
9
《Science Foundation in China》 CAS 2017年第4期19-,共1页
With the support by the National Natural Science Foundation of China,the research team led by Prof.Hou Yu(侯宇)and Prof.Yang Huagui(杨化桂)at the Key Laboratory for Ultrafine Materials of Ministry of Education,School ... With the support by the National Natural Science Foundation of China,the research team led by Prof.Hou Yu(侯宇)and Prof.Yang Huagui(杨化桂)at the Key Laboratory for Ultrafine Materials of Ministry of Education,School of Materials Science and Engineering,East China University of Science 展开更多
关键词 Efficient perovskite solar cells based on the novel low-temperature processed electron transport layer ETL PCE
原文传递
Numerical simulation of the sticking process of glass-microparticles to a fiat wall to represent pollutant-particles treatment in a multi-channel cyclone 被引量:2
10
作者 Raimondas Jasevicius Harald Kruggel-Emden Pranas Baltrenas 《Particuology》 SCIE EI CAS CSCD 2017年第3期112-131,共20页
Ultrafine particles are dangerous to human health and are usually difficult to separate from airflow because of their low inertia, which helps them to stick easily to surfaces because of adhesive forces. This characte... Ultrafine particles are dangerous to human health and are usually difficult to separate from airflow because of their low inertia, which helps them to stick easily to surfaces because of adhesive forces. This characteristic provides opportunities for adhesive ultrafine particle separation by designing air-cleaning devices that exploit the sticking ability. To understand governing effects in such air-cleaning devices, which can be designed as multi-channel cyclones, the sticking of adhesive spherical glass particles under oblique impact has been investigated numerically by using the discrete element method. An adhesive dissipative contact model was applied by implementing different interaction forces for various-sized ultraflne pollutant particles. Normal loading is represented by the elastic Hertz contact model, whereas viscous damping is described by the modified nonlinear Tsuji model. The influence of deformation- dependent adhesive forces for a range of ultrafine particle sizes is illustrated during the sticking process. Dissipative oscillations during the sticking process were observed because of the influence of viscous damping forces. 展开更多
关键词 Adhesion Discrete element method Microparticles Multi-channel cyclone Sticking process Boundary layer
原文传递
Interfacial engineering of printable bottom back metal electrodes for full-solution processed flexible organic solar cells 被引量:2
11
作者 Hongyu Zhen Kan Li +9 位作者 Yaokang Zhang Lina Chen Liyong Niu Xiaoling Wei Xu Fang Peng You Zhike Liu Dongrui Wang Feng Yan Zijian Zheng 《Journal of Semiconductors》 EI CAS CSCD 2018年第1期215-223,共9页
Printing of metal bottom back electrodes of flexible organic solar cells(FOSCs) at low temperature is of great significance to realize the full-solution fabrication technology. However, this has been difficult to ac... Printing of metal bottom back electrodes of flexible organic solar cells(FOSCs) at low temperature is of great significance to realize the full-solution fabrication technology. However, this has been difficult to achieve because often the interfacial properties of those printed electrodes, including conductivity, roughness, work function,optical and mechanical flexibility, cannot meet the device requirement at the same time. In this work, we fabricate printed Ag and Cu bottom back cathodes by a low-temperature solution technique named polymer-assisted metal deposition(PAMD) on flexible PET substrates. Branched polyethylenimine(PEI) and ZnO thin films are used as the interface modification layers(IMLs) of these cathodes. Detailed experimental studies on the electrical, mechanical, and morphological properties, and simulation study on the optical properties of these IMLs are carried out to understand and optimize the interface of printed cathodes. We demonstrate that the highest power conversion efficiency over 3.0% can be achieved from a full-solution processed OFSC with the device structure being PAMDAg/PEI/P3 HT:PC61BM/PH1000. This device also acquires remarkable stability upon repeating bending tests. 展开更多
关键词 polymer-assisted metal deposition full-solution processed flexible organic solar cells printed electrodes interface modification layers
原文传递
Process Design for Hybrid Sheet Metal Components
12
作者 Rico Haase Roland Müller +2 位作者 Dirk Landgrebe Peter Scholz Matthias Riemer 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2015年第12期1518-1524,共7页
The global trends towards improving fuel efficiency and reducing CO;emissions are the key drivers for lightweight solutions. In sheet metal processing, this can be achieved by the use of materials with a supreme stren... The global trends towards improving fuel efficiency and reducing CO;emissions are the key drivers for lightweight solutions. In sheet metal processing, this can be achieved by the use of materials with a supreme strength-toweight and stiffness-to-weight ratio. Besides monolithic materials such as high-strength or light metals, in particular metal–plastic composite sheets are able to provide outstanding mechanical properties. Thus, the adaption of conventional, wellestablished forming methods for the processing of hybrid sheet metals is a current challenge for the sheet metal working industry. In this work, the planning phase for a conventional sheet metal forming process is studied aiming at the forming of metal–plastic composite sheets. The single process steps like material characterization, FE analysis, tool design and development of robust process parameters are studied in detail and adapted to the specific properties of metal–plastic composites. In material characterization, the model of the hybrid laminate needs to represent not only the mechanical properties of the individual combined materials, but also needs to reflect the behaviour of the interface zone between them.Based on experience, there is a strong dependency on temperature as well as strain rate. While monolithic materials show a moderate anisotropic behaviour, loads on laminates in different directions generate different strain states and completely different failure modes. During the FE analysis, thermo-mechanic and thermo-dynamic effects influence the temperature distribution within tool and work pieces and subsequently the forming behaviour. During try out and production phase,those additional influencing factors are limiting the process window even more and therefore need to be considered for the design of a robust forming process. A roadmap for sheet metal forming adjusted to metal–plastic composites is presented in this paper. 展开更多
关键词 Characterization Hybrids Interface layered structures processing Sheet forming
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部