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The Design of I/O Subsystem in Satellite Real-Time Microkernel Operating System 被引量:1
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作者 Liu Xiaodong & Li Lianzhi (Dept. of Computer Science & Engineering, Harbin Institute of Technology, 150001, P. R. China) Qian Chunlai(Beijiing Institute of Radio Measurement, 100854, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1998年第3期77-81,共5页
One of the most important features of modern minor satellites is to realize autonomous moving. The performance of the satellite autonomous computer operating system acting as the control center is utmost important. Th... One of the most important features of modern minor satellites is to realize autonomous moving. The performance of the satellite autonomous computer operating system acting as the control center is utmost important. The recent trend in operating system development is adopting microkernel architecture which holds such advantages as microminiaturization, modularity, portability and extendibility. The performance of I/O subsystem is currently receiving considerable research attention. Object-orientation offers an approach to application development in which software system can be constructed by composing and refining the pre-designed plug-compatible software components.It also starts with some basic notions fairly well accepted in computer science, namely encapsulation and reuse. In this paper, a new object-oriented real-time I/O subsystem model has been designed.In this model, the traditional I/O subsystem framework is discarded and a stream mechanism based on the object-oriented concept is introduced. In addition, the I/O requests are classified according to their time emergency to obtain real-time performance. So, this model meets such satelliteperformance requirements as reliability, flexibility, portability and real-time performance. 展开更多
关键词 Satellite operating system I/O subsystem OBJECT-ORIENTED real-time
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Perspectives on risk analysis and control for real-time operation of flood control systems 被引量:2
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作者 Juan Chen Lu Zhang +1 位作者 Guo-zhi Li Ping-an Zhong 《Water Science and Engineering》 CSCD 2024年第4期319-322,共4页
Flood control operation,a non-engineering measure,can efficiently manage flood disasters within a river basin.However,numerous uncertainties exit in the real-time operation of flood control systems,creating risks in d... Flood control operation,a non-engineering measure,can efficiently manage flood disasters within a river basin.However,numerous uncertainties exit in the real-time operation of flood control systems,creating risks in decision-making.As an efficient tool to mitigate these risks,risk management has garnered increasing attention in real-time flood control operation.This communication offers a series of suggestions for future research concerning risk management in real-time flood control operation,including risk assessment,risk diagnosis,and risk control methods. 展开更多
关键词 Flood control system real-time operation Risk management Risk analysis Risk control
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Low-Power Operational Amplifier for Real-Time Signal Processing System of Micro Air Vehicle
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作者 王竹萍 仲顺安 聂丹丹 《Journal of Beijing Institute of Technology》 EI CAS 2010年第3期353-356,共4页
A low-power complementary metal oxide semiconductor(CMOS) operational amplifier (op-amp) for real-time signal processing of micro air vehicle (MAV) is designed in this paper.Traditional folded cascode architectu... A low-power complementary metal oxide semiconductor(CMOS) operational amplifier (op-amp) for real-time signal processing of micro air vehicle (MAV) is designed in this paper.Traditional folded cascode architecture with positive channel metal oxide semiconductor(PMOS) differential input transistors and sub-threshold technology are applied under the low supply voltage.Simulation results show that this amplifier has significantly low power,while maintaining almost the same gain,bandwidth and other key performances.The power required is only 0.12 mW,which is applicable to low-power and low-voltage real-time signal acquisition and processing system. 展开更多
关键词 microelectromechanical system(MEMS) operational amplifier(op-amp) LOW-POWER real-time signal processing system micro air vehicle(MAV)
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Real-Time Operation of Microgrids
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作者 Salem Al-Agtash Asma Alkhraibat +1 位作者 Mohamad Al Hashem Nisrein Al-Mutlaq 《Energy and Power Engineering》 2021年第1期51-66,共16页
Microgrid (MG) systems effectively integrate a generation mix of solar, wind, and other renewable energy resources. The intermittent nature of renewable resources and the unpredictable weather conditions contribute la... Microgrid (MG) systems effectively integrate a generation mix of solar, wind, and other renewable energy resources. The intermittent nature of renewable resources and the unpredictable weather conditions contribute largely to the unreliability of microgrid real-time operation. This paper investigates the behavior of microgrid for different intermittent scenarios of photovoltaic generation in real-time. Reactive power coordination control and load shedding mechanisms are used for reliable operation and are implemented using OPAL-RT simulator integrated with Matlab. In an islanded MG, load shedding can be an effective mechanism to maintain generation-load balance. The microgrid of the German Jordanian University (GJU) is used for illustration. The results show that reactive power coordination control not only stabilizes the MG operation in real-time but also reduces power losses on transmission lines. The results also show that the power losses at some substations are reduced by a range of 6% - 9.8%. 展开更多
关键词 Microgrid real-time operation Reactive Power Control Load Shedding OPAL-RT MATLAB
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Transformer real-time reliability model based on operating conditions 被引量:10
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作者 HE Jian CHENG Lin SUN Yuan-zhang 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第3期378-383,共6页
Operational reliability evaluation theory reflects real-time reliability level of power system. The component failure rate varies with operating conditions. The impact of real-time operating conditions such as ambient... Operational reliability evaluation theory reflects real-time reliability level of power system. The component failure rate varies with operating conditions. The impact of real-time operating conditions such as ambient temperature and transformer MVA (megavolt-ampere) loading on transformer insulation life is studied in this paper. The formula of transformer failure rate based on the winding hottest-spot temperature (HST) is given. Thus the real-time reliability model of transformer based on oper- ating conditions is presented. The work is illustrated using the 1979 IEEE Reliability Test System. The changes of operating conditions are simulated by using hourly load curve and temperature curve, so the curves of real-time reliability indices are ob- tained by using operational reliability evaluation. 展开更多
关键词 operational reliability real-time reliability model TRANSFORMER Winding hottest-pot temperature (HST)
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Evolution analysis of a UAV real-time operating system from a network perspective 被引量:4
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作者 Zheng ZHENG Guanping XIAO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第1期176-185,共10页
With the flourishing development of Unmanned Aerial Vehicles(UAVs), the mission tasks of UAVs have become more and more complex. Consequently, a Real-Time Operating System(RTOS) that provides operating environments fo... With the flourishing development of Unmanned Aerial Vehicles(UAVs), the mission tasks of UAVs have become more and more complex. Consequently, a Real-Time Operating System(RTOS) that provides operating environments for various mission services on these UAVs has become crucial, which leads to the necessity of having a deep understanding of an RTOS. In this paper, an empirical study is conducted on FreeRTOS, a commonly used RTOS for UAVs, from a complex network perspective. A total of 85 releases of FreeRTOS, from V2.4.2 to V10.0.0, are modeled as directed networks, in which the nodes represent functions and the edges denote function calls. It is found that the size of the FreeRTOS network has grown almost linearly with the evolution of the versions, while its main core has evolved steadily. In addition, a k-core analysis-based metric is proposed to identify major functionality changes of FreeRTOS during its evolution.The result shows that the identified versions are consistent with the version change logs. Finally,it is found that the clustering coefficient of the Linux OS scheduler is larger than that of the FreeRTOS scheduler. In conclusion, the empirical results provide useful guidance for developers and users of UAV RTOSs. 展开更多
关键词 COMPLEX networks Evolution FREERTOS k-core DECOMPOSITION real-time operating system
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Homology Priority Task Scheduling in μC/OS-Ⅱ Real-Time Kernel
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作者 WANG Xibo ZHOU Benhai +1 位作者 YU Gei LI Qian 《Wuhan University Journal of Natural Sciences》 CAS 2007年第5期946-950,共5页
μC/OS-Ⅱ is an open source real-time kernel adopting priority preemptive schedule strategy. Aiming at the problem of μC/OS-Ⅱ failing to support homology priority tasks scheduling, an approach for solution is propos... μC/OS-Ⅱ is an open source real-time kernel adopting priority preemptive schedule strategy. Aiming at the problem of μC/OS-Ⅱ failing to support homology priority tasks scheduling, an approach for solution is proposed. The basic idea is adding round-robin scheduling strategy in its original scheduler in order to schedule homology priority tasks through time slice roundrobin. Implementation approach is given in detail. Firstly, the Task Control Block (TCB) is extended. And then, a new priority index table is created, in which each index pointer points to a set of homology priority tasks. Eventually, on the basis of reconstructing μC/OS-Ⅱ real-time kernel, task scheduling module is rewritten. Otherwise, schedulability of homology task supported by modified kernel had been analyzed, and deadline formula of created homology tasks is given. By theoretical analysis and experiment verification, the modified kernel can support homology priority tasks scheduling, meanwhile, it also remains preemptive property of original μC/OS-Ⅱ. 展开更多
关键词 μC/OS-Ⅱ real-time kernel homology priority task round-robin
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Digital arc welding power supply based on real-time operating system
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作者 张红兵 黄石生 周漪清 《China Welding》 EI CAS 2007年第3期1-5,共5页
A digital arc welding power supply was designed with the advanced reduced instruction set computer machine (ARM) and embedded real-time multi-task operating system micro C/OS- Ⅱ. The ARM, with its powerful calculat... A digital arc welding power supply was designed with the advanced reduced instruction set computer machine (ARM) and embedded real-time multi-task operating system micro C/OS- Ⅱ. The ARM, with its powerful calculating speed and complete peripheral equipments, is very suitable to work as the controller of the digital power supply. The micro C/OS- Ⅱ transplanted in ARM, helps to improve the respondent speed against various welding signals, as well as the reliability of the controlling software. The welding process consists of nine tasks. The tasks of great significance on reliability of the welder, for example, the A/D conversion of current and voltage, enjoy top priority. To avoid simultaneous-sharing on A/D converter and LCD module, two semaphores are introduced in to ensure the smooth performance of the welding power supply. Proven by experiments ,the ARM and the micro C/OS- Ⅱ can greatly improve both the respondent speed and the reliability of the digital welder. 展开更多
关键词 micro C/OS-Ⅱ real-time operating system DIGITIZATION arc welding power supply
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A Smart Phone-oriented Embedded Real-time Operating System
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作者 Wang Jigang Gu Guochang Xu Lifeng 《ZTE Communications》 2005年第4期6-10,共5页
This article presents an embedded Smart Phone Operating System(SPOS)independently designed by ZTE Corporation.The SPOS is based on single kernel architecture with its multi-task real-time kernel supporting hardware pl... This article presents an embedded Smart Phone Operating System(SPOS)independently designed by ZTE Corporation.The SPOS is based on single kernel architecture with its multi-task real-time kernel supporting hardware platforms and resources of mainstream mobile phones.It has remarkable advantages such as highly efficient and dynamic power management,priority-based preemptive scheduling,fast startup,a variety of drivers,and excellent system stability and operability.For the development of upper layer communication protocols and application software,the SPOS provides wireless communication interfaces and the application program framework. 展开更多
关键词 PHONE SPOS TIME A Smart Phone-oriented Embedded real-time operating System
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The Boundedness of Littlewood-Paley Operators with Rough Kernels on Weighted (L^q , L^p )~α (R^n) Spaces 被引量:5
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作者 Ximei Wei Shuangping Tao 《Analysis in Theory and Applications》 2013年第2期135-148,共14页
In this paper, we shall deal with the boundedness of the Littlewood-Paley operators with rough kernel. We prove the boundedness of the Lusin-area integral μΩs and Littlewood-Paley functions μΩ and μλ^* on the w... In this paper, we shall deal with the boundedness of the Littlewood-Paley operators with rough kernel. We prove the boundedness of the Lusin-area integral μΩs and Littlewood-Paley functions μΩ and μλ^* on the weighted amalgam spaces (Lω^q,L^p)^α(R^n)as 1〈q≤α〈p≤∞. 展开更多
关键词 Littlewood-Paley operator weighted amalgam space rough kernel Ap weight.
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A pre-generated matrix-based method for real-time robotic drilling chatter monitoring 被引量:10
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作者 Jianfeng TAO Chengjin QIN +2 位作者 Dengyu XIAO Haotian SHI Chengliang LIU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第12期2755-2764,共10页
Currently, due to the detrimental effects on surface finish and machining system, chatter has been one crucial factor restricting robotic drilling operations, which improve both quality and efficiency of aviation manu... Currently, due to the detrimental effects on surface finish and machining system, chatter has been one crucial factor restricting robotic drilling operations, which improve both quality and efficiency of aviation manufacturing. Based on the matrix notch filter and fast wavelet packet decomposition, this paper presents a novel pre-generated matrix-based real-time chatter monitoring method for robotic drilling. Taking vibration characteristics of robotic drilling into account, the matrix notch filter is designed to eliminate the interference of spindle-related components on the measured vibration signal. Then, the fast wavelet packet decomposition is presented to decompose the filtered signal into several equidistant frequency bands, and the energy of each sub-band is obtained. Finally, the energy entropy which characterizes inhomogeneity of energy distribution is utilized as the feature to recognize chatter on-line, and the effectiveness of the presented algorithm is validated by extensive experimental data. The results show that the proposed algorithm can effectively detect chatter before it is fully developed. Moreover, since both filtering and decomposition of signal are implemented by the pre-generated matrices, calculation for an energy entropy of vibration signal with 512 samples takes only about 0.690 ms. Consequently, the proposed method achieves real-time chatter monitoring for robotic drilling, which is essential for subsequent chatter suppression. 展开更多
关键词 Aviation manufacturing Fast wavelet packet decomposition Matrix notch filter real-time chatter monitoring Robotic drilling operations
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A Concept of Dynamically Reconfigurable Real-time Vision System for Autonomous Mobile Robotics 被引量:3
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作者 Aymeric De Cabrol Thibault Garcia +1 位作者 Patrick Bonnin Maryline Chetto 《International Journal of Automation and computing》 EI 2008年第2期174-184,共11页
This paper describes specific constraints of vision systems that are dedicated to be embedded in mobile robots. If PC-based hardware architecture is convenient in this field because of its versatility, flexibility, pe... This paper describes specific constraints of vision systems that are dedicated to be embedded in mobile robots. If PC-based hardware architecture is convenient in this field because of its versatility, flexibility, performance, and cost, current real-time operating systems are not completely adapted to long processing with varying duration, and it is often necessary to oversize the system to guarantee fail-safe functioning. Also, interactions with other robotic tasks having more priority are difficult to handle. To answer this problem, we have developed a dynamically reconfigurable vision processing system, based on the innovative features of Cleopatre real-time applicative layer concerning scheduling and fault tolerance. This framework allows to define emergency and optional tasks to ensure a minimal quality of service for the other subsystems of the robot, while allowing to adapt dynamically vision processing chain to an exceptional overlasting vision process or processor overload. Thus, it allows a better cohabitation of several subsystems in a single hardware, and to develop less expensive but safe systems, as they will be designed for the regular case and not rare exceptional ones. Finally, it brings a new way to think and develop vision systems, with pairs of complementary operators. 展开更多
关键词 real-time vision dynamic reconfiguration embedded systems ROBUSTNESS real-time operating system
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APPLICATIONS OF THE BERNSTEIN-DURRMEYER OPERATORS IN ESTIMATING THE NORM OF MERCER KERNEL MATRICES 被引量:2
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作者 Chunping Zhang Baohuai Sheng Zhixiang Chen 《Analysis in Theory and Applications》 2008年第1期74-86,共13页
The paper is related to the norm estimate of Mercer kernel matrices. The lower and upper bound estimates of Rayleigh entropy numbers for some Mercer kernel matrices on [0, 1] × [0, 1] based on the Bernstein-Durrm... The paper is related to the norm estimate of Mercer kernel matrices. The lower and upper bound estimates of Rayleigh entropy numbers for some Mercer kernel matrices on [0, 1] × [0, 1] based on the Bernstein-Durrmeyer operator kernel are obtained, with which and the approximation property of the Bernstein-Durrmeyer operator the lower and upper bounds of the Rayleigh entropy number and the l2 -norm for general Mercer kernel matrices on [0, 1] x [0, 1] are provided. 展开更多
关键词 Mercer kernel matrix Rayleigh entropy number Bernstein-Durrmeyer operator
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Toeplitz Type Operator Associated to Singular Integral Operator with Variable Kernel on Weighted Morrey Spaces 被引量:1
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作者 Yuexiang He Yueshan Wang 《Analysis in Theory and Applications》 CSCD 2016年第1期90-102,共13页
Suppose T^k,l and T^k,2 are singular integrals with variable kernels and mixed homogeneity or ±I (the identity operator). Denote the Toeplitz type operator by T^b=k=1∑^QT^k,1M^bT^k,2 where M^bf= bf. In this pa... Suppose T^k,l and T^k,2 are singular integrals with variable kernels and mixed homogeneity or ±I (the identity operator). Denote the Toeplitz type operator by T^b=k=1∑^QT^k,1M^bT^k,2 where M^bf= bf. In this paper, the boundedness of Tb on weighted Morrey space are obtained when b belongs to the weighted Lipschitz function space and weighted BMO function space, respectively. 展开更多
关键词 Toeplitz type operator singular integral operator variable Calderon-Zygmund kernel weighted BMO function weighted Lipschitz function weighted Morrey space.
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DEVELOPMENT OF AN AIRBORNE SAR REAL-TIME DIGITAL IMAGING PROCESSOR 被引量:1
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作者 Zhu Xixing Jin Lingjiao Huang Ling(institute of Electronics, Academia Sinica, Beijing 100080) 《Journal of Electronics(China)》 1996年第2期116-121,共6页
An airborne SAR real-time digital imaging processor is presented, and its realtime digital imaging principle and main technical parameters are analyzed briefly. The system configuration and logical structure are descr... An airborne SAR real-time digital imaging processor is presented, and its realtime digital imaging principle and main technical parameters are analyzed briefly. The system configuration and logical structure are described in detail. Finally the main features of this system and examples of imagery obtained with the system are also presented. 展开更多
关键词 SAR real-time IMAGING PROCESSOR MULTIPROCESSOR operation system
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MODEL-BASED DEVELOPMENT OF REAL-TIME SOFTWARE SYSTEM FOR ELECTRONIC UNIT PUMP SYSTEM 被引量:1
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作者 YU Shitao YANG Shiwei YANG Lin GONG Yuanming ZHUO Bin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第1期25-30,共6页
A real-time operating system (RTOS), also named OS, is designed based on the hardware platform of MC68376, and is implemented in the electronic control system for unit pump in diesel engine. A parallel and time-base... A real-time operating system (RTOS), also named OS, is designed based on the hardware platform of MC68376, and is implemented in the electronic control system for unit pump in diesel engine. A parallel and time-based task division method is introduced and the multi-task software architecture is built in the software system for electronic unit pump (EUP) system. The V-model software development process is used to control algorithm of each task. The simulation results of the hardware-in-the-loop simulation system (HILSS) and the engine experimental results show that the OS is an efficient real-time kernel, and can meet the real-time demands of EUP system; The built multi-task software system is real-time, determinate and reliable. V-model development is a good development process of control algorithms for EUP system, the control precision of control system can be ensured, and the development cycle and cost are also decreased. 展开更多
关键词 real-time operating system (RTOS) Multi-task V-model development Hardware-in-the-loop simulation system(HILSS) Electronic unit pump (EUP)
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BOUNDEDNESS OF MULTILINEAR OPERATORS WITH ROUGH KERNEL ON HERZ SPACES
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作者 Chen Dongxiang Chen JiechengDept. of Math., Zhejiang Univ.,Hangzhou 310028,China. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2003年第4期467-476,共10页
In this paper,the boundedness of the multilinear operators with rough kernel on the Herz-type spaces is discussed.It is proved that M A,Ω,T A,Ω are bounded on α,p q(Rn) while Mλ A,Ω,TL A,Ω are bou... In this paper,the boundedness of the multilinear operators with rough kernel on the Herz-type spaces is discussed.It is proved that M A,Ω,T A,Ω are bounded on α,p q(Rn) while Mλ A,Ω,TL A,Ω are bounded from α,p 1 q 1(Rn) to α,p 2 q 2(Rn),respectively. 展开更多
关键词 multilinear operator rough kernel Herz space maximal operator
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FAST ALGORITHM FOR CALDERóN-ZYGMUND OPERATORS:CONVERGENCE SPEED AND ROUGH KERNEL
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作者 杨奇祥 丁勇 《Acta Mathematica Scientia》 SCIE CSCD 2016年第2期345-358,共14页
In this article, we consider a fast algorithm for first generation Calderon-Zygmund operators. First, we estimate the convergence speed of the relative approximation algorithm. Then, we establish the continuity on Bes... In this article, we consider a fast algorithm for first generation Calderon-Zygmund operators. First, we estimate the convergence speed of the relative approximation algorithm. Then, we establish the continuity on Besov spaces and Triebel-Lizorkin spaces for the oper- ators with rough kernel. 展开更多
关键词 First generation Calderon-Zygmund operators WAVELETS rough kernel ring type operators Besov spaces and Triebel-Lizorkin spaces
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Air Traffic Operation Complexity Analysis Based on Metrics System
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作者 Xie Hua Cong Wei +1 位作者 Hu Ming hua Liu Sifeng 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第4期461-468,共8页
In order to quantitatively analyze air traffic operation complexity,multidimensional metrics were selected based on the operational characteristics of traffic flow.The kernel principal component analysis method was ut... In order to quantitatively analyze air traffic operation complexity,multidimensional metrics were selected based on the operational characteristics of traffic flow.The kernel principal component analysis method was utilized to reduce the dimensionality of metrics,therefore to extract crucial information in the metrics.The hierarchical clustering method was used to analyze the complexity of different airspace.Fourteen sectors of Guangzhou Area Control Center were taken as samples.The operation complexity of traffic situation in each sector was calculated based on real flight radar data.Clustering analysis verified the feasibility and rationality of the method,and provided a reference for airspace operation and management. 展开更多
关键词 operation complexity traffic metrics kernel primary component analysis hierarchical clustering
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Weighted estimates for strongly singular integral operators with rough kernels
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作者 黄文礼 陶祥兴 李胜宏 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第6期761-768,共8页
The Fourier transform and the Littlewood-Paley theory are used to give the weighted boundedness of a strongly singular integral operator defined in this paper. The paper shows that the strongly singular integral opera... The Fourier transform and the Littlewood-Paley theory are used to give the weighted boundedness of a strongly singular integral operator defined in this paper. The paper shows that the strongly singular integral operator is bounded from the Sobolev space to the Lebesgue space. 展开更多
关键词 strongly singular integral operators rough kernels Ap weights
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