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Unknown DDoS Attack Detection with Fuzzy C-Means Clustering and Spatial Location Constraint Prototype Loss
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作者 Thanh-Lam Nguyen HaoKao +2 位作者 Thanh-Tuan Nguyen Mong-Fong Horng Chin-Shiuh Shieh 《Computers, Materials & Continua》 SCIE EI 2024年第2期2181-2205,共25页
Since its inception,the Internet has been rapidly evolving.With the advancement of science and technology and the explosive growth of the population,the demand for the Internet has been on the rise.Many applications i... Since its inception,the Internet has been rapidly evolving.With the advancement of science and technology and the explosive growth of the population,the demand for the Internet has been on the rise.Many applications in education,healthcare,entertainment,science,and more are being increasingly deployed based on the internet.Concurrently,malicious threats on the internet are on the rise as well.Distributed Denial of Service(DDoS)attacks are among the most common and dangerous threats on the internet today.The scale and complexity of DDoS attacks are constantly growing.Intrusion Detection Systems(IDS)have been deployed and have demonstrated their effectiveness in defense against those threats.In addition,the research of Machine Learning(ML)and Deep Learning(DL)in IDS has gained effective results and significant attention.However,one of the challenges when applying ML and DL techniques in intrusion detection is the identification of unknown attacks.These attacks,which are not encountered during the system’s training,can lead to misclassification with significant errors.In this research,we focused on addressing the issue of Unknown Attack Detection,combining two methods:Spatial Location Constraint Prototype Loss(SLCPL)and Fuzzy C-Means(FCM).With the proposed method,we achieved promising results compared to traditional methods.The proposed method demonstrates a very high accuracy of up to 99.8%with a low false positive rate for known attacks on the Intrusion Detection Evaluation Dataset(CICIDS2017)dataset.Particularly,the accuracy is also very high,reaching 99.7%,and the precision goes up to 99.9%for unknown DDoS attacks on the DDoS Evaluation Dataset(CICDDoS2019)dataset.The success of the proposed method is due to the combination of SLCPL,an advanced Open-Set Recognition(OSR)technique,and FCM,a traditional yet highly applicable clustering technique.This has yielded a novel method in the field of unknown attack detection.This further expands the trend of applying DL and ML techniques in the development of intrusion detection systems and cybersecurity.Finally,implementing the proposed method in real-world systems can enhance the security capabilities against increasingly complex threats on computer networks. 展开更多
关键词 CYBERSECURITY DDoS unknown attack detection machine learning deep learning incremental learning convolutional neural networks(CNN) open-set recognition(OSR) spatial location constraint prototype loss fuzzy c-means CICIDS2017 CICDDoS2019
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The Advertisement Translation Based on the Prototype Theory
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作者 XUE Hai-bin 《Sino-US English Teaching》 2024年第3期132-137,共6页
Based on the Prototype Theory,the prototypical feature of advertisement is found to be the combination of three language functions:the informative function,the expressive function,and the vocative function.The adverti... Based on the Prototype Theory,the prototypical feature of advertisement is found to be the combination of three language functions:the informative function,the expressive function,and the vocative function.The advertisement translation means the adjustment of the informative function and the expressive function according to the differences between languages or cultures in order to maximize the vocative function.The faithful translation is the closest to the prototype of the source text but not necessarily the best translation. 展开更多
关键词 the prototype Theory ADVERTISEMENT the informative function the expressive function the vocative function
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Rapid Prototype Development Approach for Genetic Programming
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作者 Pei He Lei Zhang 《Journal of Computer and Communications》 2024年第2期67-79,共13页
Genetic Programming (GP) is an important approach to deal with complex problem analysis and modeling, and has been applied in a wide range of areas. The development of GP involves various aspects, including design of ... Genetic Programming (GP) is an important approach to deal with complex problem analysis and modeling, and has been applied in a wide range of areas. The development of GP involves various aspects, including design of genetic operators, evolutionary controls and implementations of heuristic strategy, evaluations and other mechanisms. When designing genetic operators, it is necessary to consider the possible limitations of encoding methods of individuals. And when selecting evolutionary control strategies, it is also necessary to balance search efficiency and diversity based on representation characteristics as well as the problem itself. More importantly, all of these matters, among others, have to be implemented through tedious coding work. Therefore, GP development is both complex and time-consuming. To overcome some of these difficulties that hinder the enhancement of GP development efficiency, we explore the feasibility of mutual assistance among GP variants, and then propose a rapid GP prototyping development method based on πGrammatical Evolution (πGE). It is demonstrated through regression analysis experiments that not only is this method beneficial for the GP developers to get rid of some tedious implementations, but also enables them to concentrate on the essence of the referred problem, such as individual representation, decoding means and evaluation. Additionally, it provides new insights into the roles of individual delineations in phenotypes and semantic research of individuals. 展开更多
关键词 Genetic Programming Grammatical Evolution Gene Expression Programming Regression Analysis Mathematical Modeling Rapid prototype Development
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The Role and Place of Artificial Neural Network Architectures Structural Redundancy in the Input Data Prototypes and Generalization Development
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作者 Conrad Onésime Oboulhas Tsahat Ngoulou-A-Ndzeli Béranger Destin Ossibi 《Journal of Computer and Communications》 2024年第7期1-11,共11页
Neural Networks (NN) are the functional unit of Deep Learning and are known to mimic the behavior of the human brain to solve complex data-driven problems. Whenever we train our own neural networks, we need to take ca... Neural Networks (NN) are the functional unit of Deep Learning and are known to mimic the behavior of the human brain to solve complex data-driven problems. Whenever we train our own neural networks, we need to take care of something called the generalization of the neural network. The performance of Artificial Neural Networks (ANN) mostly depends upon its generalization capability. In this paper, we propose an innovative approach to enhance the generalization capability of artificial neural networks (ANN) using structural redundancy. A novel perspective on handling input data prototypes and their impact on the development of generalization, which could improve to ANN architectures accuracy and reliability is described. 展开更多
关键词 Multilayer Neural Network Multidimensional Nonlinear Interpolation Generalization by Similarity Artificial Intelligence prototype Development
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A multi-purpose prototype test system for mechanical behavior of tunnel supporting structure: Development and application 被引量:1
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作者 Hongbin Chen Xinhua You +1 位作者 Dajun Yuan Yang Ping 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第2期467-476,共10页
A multi-purpose prototype test system is developed to study the mechanical behavior of tunnel sup-porting structure,including a modular counterforce device,a powerful loading equipment,an advanced intelligent manageme... A multi-purpose prototype test system is developed to study the mechanical behavior of tunnel sup-porting structure,including a modular counterforce device,a powerful loading equipment,an advanced intelligent management system and an efficient noncontact deformation measurement system.The functions of the prototype test system are adjustable size and shape of the modular counterforce structure,sufficient load reserve and accurate loading,multi-connection linkage intelligent management,and high-precision and continuously positioned noncontact deformation measurement.The modular counterforce structure is currently the largest in the world,with an outer diameter of 20.5 m,an inner diameter of 16.5 m and a height of 6 m.The case application proves that the prototype test system can reproduce the mechanical behavior of the tunnel lining during load-bearing,deformation and failure processes in detail. 展开更多
关键词 prototype test system Tunnel supporting structure Tunnel fire LINING Mechanical behavior
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Prototypes and Vocabulary Teaching
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作者 王乐 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2006年第S1期337-338,共2页
The prototype theory suggests that many metal concepts we have are really prototypes.It claims that children first learn words that are "basic" because they reflect aspects of the world,prototypes, which sta... The prototype theory suggests that many metal concepts we have are really prototypes.It claims that children first learn words that are "basic" because they reflect aspects of the world,prototypes, which stand out automatically from the rest of what they see.Basic level words should be taught first. 展开更多
关键词 prototype prototype theory prototype theory of vocabulary
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Development and preliminary results of a large-pixel two-layer LaBr_(3) Compton camera prototype
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作者 Ming-Hao Dong Zhi-Yang Yao Yong-Shun Xiao 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第8期100-114,共15页
Lanthanum bromide(LaBr_(3))crystal has a high energy resolution and time resolution and has been used in Compton cameras(CCs)over the past few decades.However,LaBr_(3) crystal arrays are difficult to process because L... Lanthanum bromide(LaBr_(3))crystal has a high energy resolution and time resolution and has been used in Compton cameras(CCs)over the past few decades.However,LaBr_(3) crystal arrays are difficult to process because LaBr_(3) is easy to crack and break;thus,few LaBr_(3)-based CC prototypes have been built.In this study,we designed and fabricated a large-pixel LaBr_(3) CC prototype and evaluated its performance with regard to position,energy,and angular resolution.We used two 10×10 LaBr_(3) crystal arrays with a pixel size of 5 mm×5 mm,silicon photomultipliers(SiPMs),and corresponding decoding circuits to construct our prototype.Additionally,a framework based on a Voronoi diagram and a lookup table was developed for list-mode projection data acquisition.Monte Carlo(MC)simulations based on Geant4 and experiments were conducted to evaluate the performance of our CC prototype.The lateral position resolution was 5 mm,and the maximum deviation in the depth direction was 2.5 and 5 mm for the scatterer and absorber,respectively.The corresponding measured energy resolu-tions were 7.65%and 8.44%,respectively,at 511 keV.The experimental results of ^(137)Cs point-like sources were consistent with the MC simulation results with regard to the spatial positions and full widths at half maximum(FWHMs).The angular resolution of the fabricated prototype was approximately 6°when a point-like ^(137)Cs source was centrally placed at a distance of 5 cm from the scatterer.We proposed and investigated a large-pixel LaBr_(3) CC for the first time and verified its feasibility for use in accurate spatial positioning of radiative sources with a high angular resolution.The proposed CC can satisfy the requirements of radiative source imaging and positioning in the nuclear industry and medical applications. 展开更多
关键词 Compton camera Large pixel Gamma camera LaBr_(3)detector prototype evaluation
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UAV-Aided Data and Energy Integrated Network: System Design and Prototype Development
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作者 Xinyu Fan Jie Hu Kun Yang 《China Communications》 SCIE CSCD 2023年第7期290-302,共13页
Terminal devices deployed in outdoor environments are facing a thorny problem of power supply.Data and energy integrated network(DEIN)is a promising technology to solve the problem,which simultaneously transfers data ... Terminal devices deployed in outdoor environments are facing a thorny problem of power supply.Data and energy integrated network(DEIN)is a promising technology to solve the problem,which simultaneously transfers data and energy through radio frequency signals.State-of-the-art researches mostly focus on theoretical aspects.By contrast,we provide a complete design and implementation of a fully functioning DEIN system with the support of an unmanned aerial vehicle(UAV).The UAV can be dispatched to areas of interest to remotely recharge batteryless terminals,while collecting essential information from them.Then,the UAV uploads the information to remote base stations.Our system verifies the feasibility of the DEIN in practical applications. 展开更多
关键词 data and energy integrated network(DEIN) internet of things(IoT) simultaneous wire-less information and power transfer(SWIPT) wireless energy transfer(WET) prototype
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A Hyper-redundant Elephant’s Trunk Robot with an Open Structure:Design,Kinematics,Control and Prototype 被引量:3
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作者 Yongjie Zhao Xiaogang Song +1 位作者 Xingwei Zhang Xinjian Lu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2020年第6期158-176,共19页
As for the complex operational tasks in the unstructured environment with narrow workspace and numerous obstacles,the traditional robots cannot accomplish these mentioned complex operational tasks and meet the dexteri... As for the complex operational tasks in the unstructured environment with narrow workspace and numerous obstacles,the traditional robots cannot accomplish these mentioned complex operational tasks and meet the dexterity demands.The hyper-redundant bionic robots can complete complex tasks in the unstructured environments by simulating the motion characteristics of the elephant’s trunk and octopus tentacles.Compared with traditional robots,the hyper-redundant bionic robots can accomplish complex tasks because of their flexible structure.A hyper-redundant elephant’s trunk robot(HRETR)with an open structure is developed in this paper.The content includes mechanical structure design,kinematic analysis,virtual prototype simulation,control system design,and prototype building.This design is inspired by the flexible motion of an elephant’s trunk,which is expansible and is composed of six unit modules,namely,3UPS-PS parallel in series.First,the mechanical design of the HRETR is completed according to the motion characteristics of an elephant’s trunk and based on the principle of mechanical bionic design.After that,the backbone mode method is used to establish the kinematic model of the robot.The simulation software SolidWorks and ADAMS are combined to analyze the kinematic characteristics when the trajectory of the end moving platform of the robot is assigned.With the help of ANSYS,the static stiffness of each component and the whole robot is analyzed.On this basis,the materials of the weak parts of the mechanical structure and the hardware are selected reasonably.Next,the extensible structures of software and hardware control system are constructed according to the modular and hierarchical design criteria.Finally,the prototype is built and its performance is tested.The proposed research provides a method for the design and development for the hyper-redundant bionic robot. 展开更多
关键词 Hyper-redundant elephant's trunk robot Mechanical structure design Kinematic analysis Virtual prototype simulation Control system prototype building
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基于典型样本的Prototype决策树
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作者 何劲松 施泽生 《计算机工程与应用》 CSCD 北大核心 2001年第5期9-10,16,共3页
文章将SVM算法和GA-NN-C4.5算法的思路结合起来,提出了用典型样本产生原型(Prototype)的方法。实验结果表明,基于典型样本的Prototype决策树搜索效果更好、判决精度更高。
关键词 典型样本 prototype决策树 归纳学习 SVM算法 GA
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Classification and exploration potential of sedimentary basins based on the superposition and evolution process of prototype basins
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作者 DOU Lirong WEN Zhixin 《Petroleum Exploration and Development》 CSCD 2021年第6期1271-1288,共18页
Classification,superimposed evolution and sedimentary filling of prototype basins are analyzed based on the Wilson cycle principle of plate theory,by dissecting the evolution history of 483 sedimentary basins around t... Classification,superimposed evolution and sedimentary filling of prototype basins are analyzed based on the Wilson cycle principle of plate theory,by dissecting the evolution history of 483 sedimentary basins around the world since the Pre-cambrian,combined with the three stress environments of tension,compression and shear.It is found that plate tectonic evo-lution controls the superimposed development process and petroleum-bearing conditions of the prototype basins in three as-pects:first,more than 85%of the sedimentary basins in the world are developed from the superimposed development of two or more prototype basins;second,the superposition evolution process of the prototype basin takes Wilson cycle as the cycle and cycles in a fixed trajectory repeatedly.In each stage of a cycle,a specific type of prototype basin can be formed;third,each prototype basin can form a unique tectonic-sedimentary system,which determines its unique source,reservoir,cap conditions etc.For hydrocarbon accumulation,the later superimposed prototype basin can change the oil and gas accumulation conditions of the earlier prototype basin,and may form new petroleum systems.Based on this,by defining the type of a current basin as its prototype basin formed by the latest plate tectonic movement,14 types of prototype basins can be classified in the world,namely,intracontinental growth rift,intr acontinental aborted rift,intercontinental rift,passive continental margin,interior craton,trench,fore-arc rift,ba ck-arc rift,back-arc de pression,back-arc small ocean,peri pheral foreland,back-arc foreland,strike-slip pull-apart,and strike-slip flexural basins.The classification scheme can ensure the uniqueness of the types of in di-vidual sedimentary basin,and make it possible to predict their oil and gas potential scientifically through analogy. 展开更多
关键词 sedimentary basin classification plate tectonics Wilson cycle main prototype basin secondary prototype basin superposition development process
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基于Prototype的文本框自动填充功能的实现
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作者 张玉叶 《计算机时代》 2013年第6期53-55,57,共4页
以医院管理系统医生开具药方模块中文本框自动填充功能的实现为例,详细介绍了如何利用Prototype框架和基于文本的数据交换格式JSON实现文本框的自动填充功能,介绍了Prototype框架中实现AJAX的异步通信时用到的关键技术,给出了具体实现... 以医院管理系统医生开具药方模块中文本框自动填充功能的实现为例,详细介绍了如何利用Prototype框架和基于文本的数据交换格式JSON实现文本框的自动填充功能,介绍了Prototype框架中实现AJAX的异步通信时用到的关键技术,给出了具体实现过程及主要代码。实践证明,基于AJAX的异步请求原理实现的文本框的自动填充功能,不但方便了医护人员的使用,也大大提高了其工作效率,减少了病人的等待时间。 展开更多
关键词 AJAX prototype JSON 自动填充
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Evaluation of Feature Subset Selection, Feature Weighting, and Prototype Selection for Biomedical Applications
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作者 Suzanne LITTLE Sara COLANTONIO +1 位作者 Ovidio SALVETTI Petra PERNER 《Journal of Software Engineering and Applications》 2010年第1期39-49,共11页
Many medical diagnosis applications are characterized by datasets that contain under-represented classes due to the fact that the disease is much rarer than the normal case. In such a situation classifiers such as dec... Many medical diagnosis applications are characterized by datasets that contain under-represented classes due to the fact that the disease is much rarer than the normal case. In such a situation classifiers such as decision trees and Na?ve Bayesian that generalize over the data are not the proper choice as classification methods. Case-based classifiers that can work on the samples seen so far are more appropriate for such a task. We propose to calculate the contingency table and class specific evaluation measures despite the overall accuracy for evaluation purposes of classifiers for these specific data characteristics. We evaluate the different options of our case-based classifier and compare the perform-ance to decision trees and Na?ve Bayesian. Finally, we give an outlook for further work. 展开更多
关键词 FEATURE Subset SELECTION FEATURE Weighting prototype SELECTION EVALUATION of Methods prototype-Based CLASSIFICATION Methodology for prototype-Based CLASSIFICATION CBR in Health
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Prototype理论在二语词汇习得过程中的应用研究
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作者 赖妍莉 《科技风》 2009年第5期112-,共1页
基于Prototype理论探讨二语词汇习得的过程,为指导的词汇学习体现了认知语言学中认知经济的原则,不仅减轻了学习者记忆单词的负担,而且还使得枯燥的背单词行为变得灵活有趣,进而可以有效地帮助学习者习得词汇。
关键词 prototype理论 词汇习得 词汇记忆
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A Study on Senior English Vocabulary Teaching Based on Prototype Category Theory
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作者 杨安妮 《海外英语》 2021年第5期262-264,共3页
The emphasis is laid on expanding students’vocabulary in the new English Curriculum Standards.Without effective approaches to vocabulary learning,students can hardly form vocabulary networks in mind.Combining with mo... The emphasis is laid on expanding students’vocabulary in the new English Curriculum Standards.Without effective approaches to vocabulary learning,students can hardly form vocabulary networks in mind.Combining with modern educational technology,the author carries out experimental teaching to explore the effectiveness of vocabulary teaching based on prototype category theory and presents some samples of vocabulary teaching.The study shows that these teaching methods can effectively enhance students’cognition abilities,stimulate association,promote vocabulary processing,form a categorized network schema,and finally improve students’lexical competence and long-term memory. 展开更多
关键词 prototype category theory vocabulary teaching prototypical meaning prototype effect basic level
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Modeling and Simulation on Axial Piston Pump Based on Virtual Prototype Technology 被引量:29
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作者 ZHANG Bin XU Bing +1 位作者 XIA Chunlin YANG Huayong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第1期84-90,共7页
A particular emphasis is placed on the virtual prototype technology (VPT) of axial piston pump. With this technology it is convenient and flexible to build a complicated 3D virtual based on real physical model. The ... A particular emphasis is placed on the virtual prototype technology (VPT) of axial piston pump. With this technology it is convenient and flexible to build a complicated 3D virtual based on real physical model. The actual kinematics pairs of the parts were added on the model. The fluid characters were calculated by hydraulic software. The shape of the parts, the flexible body of parts, etc were improved in this prototype. So the virtual prototype of piston pump can work in computer like a real piston pump, and the flow ripple, pressure pulsation, motion principle, stress of parts, etc can be investigated. The development of the VPT is introduced at the beginning, and the modeling process of the virtual prototype is explained. Then a special emphasis is laid on the relationship between the dynamics model and the hydraulic model, and the simulations on the flow ripple, pressure pulsation, motion principle, the stress and strain distribution of the middle shaft and piston are operated. Finally, the advantages and disadvantages of the VPT are discussed. The improved virtual prototype of piston pump more tally with the real situation and the VPT has a great potential in simulation on hydraulic components. 展开更多
关键词 virtual prototype axial piston pump DYNAMICS
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Prototype for 5G New Air Interface Technology SCMA and Performance Evaluation 被引量:15
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作者 LU Lei CHEN Yan +3 位作者 GUO Wenting YANG Huilian WU Yiqun XING Shuangshuang 《China Communications》 SCIE CSCD 2015年第S1期38-48,共11页
Sparse code multiple access(SCMA) is a novel non-orthogonal multiple access scheme proposed to meet the challenging demand of the future 5G communications, especially in support of the massive connections. The coded b... Sparse code multiple access(SCMA) is a novel non-orthogonal multiple access scheme proposed to meet the challenging demand of the future 5G communications, especially in support of the massive connections. The coded bits from each data stream will be directly mapped as multi-dimensional SCMA codeword in complex domain and then spread onto the physical resource elements in a sparse manner. The number of codewords that can be nonorthogonally multiplexed in one SCMA block can be made much larger than the number of orthogonal resource elements therein, resulting in an overloaded system. The sparsity in the spreading pattern and the design in the multidimensional modulator jointly ensure the SCMA codewords can be robustly decoded with low complexity. In this paper, we focus on the low complexity receiver design and verified the superior of an SCMA system via simulations and real-time prototyping. Lab tests and field tests all show that SCMA is a promising candidate for 5G non-orthogonal multiple access which can provide up to 300% overloading that triples the whole system throughput while still enjoying the link performance close to orthogonal transmissions. 展开更多
关键词 5G non-orthogonal MULTIPLE ACCESS sparse code MULTIPLE access(SCMA) MAX-Log MPA massive CONNECTIVITY low LATENCY high reliability prototype verification
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Prototype observation and influencing factors of environmental vibrationinduced by flood discharge 被引量:8
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作者 Xin Wang Ya-an Hu +2 位作者 Shao-ze Luo Lu-chen Zhang Bo Wu 《Water Science and Engineering》 EI CAS CSCD 2017年第1期78-85,共8页
Due to a wide range of field vibration problems caused by flood discharge at the Xiangjiaba Hydropower Station, vibration characteristics and influencing factors were investigated based on prototype observation. The r... Due to a wide range of field vibration problems caused by flood discharge at the Xiangjiaba Hydropower Station, vibration characteristics and influencing factors were investigated based on prototype observation. The results indicate that field vibrations caused by flood discharge have distinctive characteristics of constancy, low frequency, small amplitude, and randomness with impact, which significantly differ from the common high-frequency vibration characteristics. Field vibrations have a main frequency of about 0.5-3.0 Hz and the characteristics of long propagation distance and large-scale impact. The vibration of a stilling basin slab runs mainly in the vertical direction. The vibration response of the guide wall perpendicular to the flow is significantly stronger than it is in other directions and decreases linearly downstream along the guide wall. The vibration response of the underground turbine floor is mainly caused by the load of unit operation. Urban environmental vibration has particular distribution characteristics and change patterns, and is greatly affected by discharge, scheduling modes, and geological conditions. Along with the increase of the height of residential buildings, vibration responses show a significant amplification effect. The horizontal and vertical vibrations of the 7th floor are, respectively, about 6 times and 1.5 times stronger than the corresponding vibrations of the 1st floor. The vibration of a large-scale chemical plant presents the combined action of flood discharge and working machines. Meanwhile, it is very difficult to reduce the low-frequency environmental vibrations. Optimization of the discharge scheduling mode is one of the effective measures of reducing the flow impact loads at present. Choosing reasonable dam sites is crucial. 展开更多
关键词 Flood discharge Environmental vibration Vibration characteristics Influencing factor prototype observation
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RESEARCH AND DEVELOPMENT OF VIRTUAL PROTOTYPE OF RUNNING GEARS FOR RAILWAY VEHICLE 被引量:6
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作者 ZOU Yisheng DING Guofu +2 位作者 ZHANG Weihua XU Mingheng HE Yong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第1期36-41,共6页
Virtual prototype is an important idea to resolve design problems of railway vehicle. A different development method, which is based on national product and autonomous development, and would like to reflect the specia... Virtual prototype is an important idea to resolve design problems of railway vehicle. A different development method, which is based on national product and autonomous development, and would like to reflect the specialty of railway vehicle development in China, is presented. According to the developing process of railway vehicle, the research contents and developing method are pointed out. The integration between CAD and performance analysis software on dynamics and strength is mainly considered. In CAD environment, the properties for dynamics computing are extracted directly from the model and exported with model. This method can avoid data losing caused by model rebuilding in CAE software, and increase the direct dependence of product CAD. Then the vehicle model with properties will be used for real-time dynamics and kinematics analysis and simulation. Therefore, the strength of the parts can be analyzed. The results of dynamics and strength analysis will be fed back to optimize the design model. All operations are dispatched by a control platform, and all data are managed according to the principle of PDM. Testing results show this method is correct. 展开更多
关键词 Virtual prototype Railway vehicle Property extraction Dynamics analysis Strength analysis
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Geochemical Constraints of Sediments on the Provenance, Depositional Environment and Tectonic Setting of the Songliao Prototype Basin 被引量:5
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作者 阎全人 高山林 +5 位作者 王宗起 李继亮 肖文交 侯泉林 阎臻 陈海泓 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2002年第4期455-462,共8页
The geochemistry of sediments is primarily controlled by their provenances,and different tectonic settings have distinctive provenance characteristics and sedimentaryprocesses. So, it is possible to distinctive proven... The geochemistry of sediments is primarily controlled by their provenances,and different tectonic settings have distinctive provenance characteristics and sedimentaryprocesses. So, it is possible to distinctive provenances, depositional environments and tectonicsettings in the development of a sedimentary basin with the geochemistry of the clastic rocks. Theanalytical results of the present paper demonstrate that sediments in the Songliao prototype basinare enriched in silica (SiO_2=66.48-80.51 percent), and their sumREE are 30-130 times of that ofchondrite with remarkable Eu anomalies. In discriminating diagrams of Eu/Eu* vs sumREE and (La/Yb)_Nvs sumREE, most samples locate above the line Eu/Eu*=1, on the right of the line Eu/Eu*/sumREE=1and under the line La/Yb)_N/sumREE=1/8, which indicates that the depositional environment ofsediments in the basin was oxidizing. In addition, variations of MgO, TiO_2, Al_2O_3, FeO + Fe_2O_3,Na_2O and CaO vs SiO_2 reflect a tendency of increasing mineral maturity of sediments in the basin.Analyses also show that the protolytes of the sediments in the basin were felsic igneous rocks, andthe Songliao prototype basin was in a tectonic setting of an island arc on an active continentalmargin, with violent sinistral strike-slip. 展开更多
关键词 Songliao prototype basin geochemistry of sediment PROVENANCE depositionalenvironment tectonic setting
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