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The AVS Workgroup has developed an IPR Policy to facilitate the adoption of standards in the marketplace The policy is based on consideration of IPR issues in parallel with the technical work for drafting the standard. The paper describes the relationship between IPR and the standard, and how the goals for the standard must be complemented by goals for the IPR. The existing IPR policies of the ITU and ISO are outlined, and then the AVS IPR policy is described, organized by its three main components: commitment to license on declared basic terms, disclosure of intellectual property, and protection of IPR.  相似文献   

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Modern agricultural machinery demands adoption of embedded electronic and remote sensing technology for precision agriculture.One of the electronic devices commonly used is the virtual terminal(VT) for tractors.A VT’s functions and terminology are described in the ISO 11783 standard.This paper presents a control system design and implementation for a VT and some other electronic control units(ECUs) for agricultural vehicles based on that standard.Hardware and software development for the VT is implemented using the ISOAgLib open library,in the advanced embedded system.The main part of the system is an embedded board based on a Samsung S3C6410 ARM11 core microprocessor with a controller area network(CAN) module.Its working environment is Windows Embedded CE 6.0(WinCE6.0).The ISOAgLib library provides abundant open sources consistent implementation of ISO 11783.It is written in C++ programming language using object-oriented technology.In this paper,we describe an ISO 11783-based tractor control system with a CAN and its implementation in the embedded system.This paper also explains the operation of a CAN-bus device driver in WinCE6.0 and some modifications of ISOAgLib for our target system.The target system consists of the VT,an ECU for the global positioning system(GPS),and an ECU for lighting for an agricultural tractor.The ECU for GPS and the ECU of a light controller are implemented using STM32F107F ARM Cortex M3-based development boards.  相似文献   

4.
An integrated 6.2–9.5 GHz UWB receiver for both WiMedia MB-OFDM and China UWB standard is proposed. The receiver can cover Group#3, Group#4 for WiMedia and Group#2–5 for China UWB standard respectively. The fully differential receiver consists of a wideband LNA and a down conversion mixer with high gain and low gain mode. A low-pass filter with controllable gain and cut-o? frequency along with a programmable gain amplifier are also included. The chip was fabricated in TSMC 0.13-μm RF CMOS process....  相似文献   

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A router architecture based upon ForCES (Forwarding and Control Element Separation), which is being standardized by IETF ForCES working group, gains its competitive advantage over traditional router architectures in flexibility, programmability, and cost-effectiveness. In this paper, design and implementation of a ForCES-based router (ForTER) is illustrated. Firstly, the implementation architecture of ForTER is discussed. Then, a layered software model, which well illustrates ForCES features, is proposed. Based on the model, design and implementation of Control Element (CE) and Forwarding Element (FE) in ForTER are introduced in detail. Moreover, security for ForTER is considered and an algorithm to prevent DoS attacks is presented. Lastly, experiments of ForTER are illustrated for routing and running routing protocols, network management, DoS attack prevention, etc. The experimental results show the feasibility of the ForTER design. Consequently, the ForTER implementation basically testifies the feasibility of ForCES architecture and some IETF ForCES specifications.  相似文献   

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This paper proposes a novel wavelet neural network algorithm for the continuous and noninvasive dynamic estimation of blood pressure(BP). Unlike prior algorithms, the proposed algorithm capitalizes on the correlation between photoplethysmography(PPG) and BP. Complete BP waveforms are reconstructed based on PPG signals to extract systolic blood pressure(SBP) and diastolic blood pressure(DBP). To improve the robustness, Daubechies wavelet is implemented as the hidden layer node function for the neural network. An optimized neural network structure is proposed to reduce the computational complexity. Further, this paper investigates an inhomogeneous resilient backpropagation(IRBP) algorithm to calculate the weight of hidden layer nodes. The IRBP improves the convergence speed and reconstruction accuracy. Multiparameter intelligent monitoring in Intensive Care(MIMIC) databases, which contain a variety of physiological parameters captured from patient monitors, are used to validate this algorithm. The standard deviation σ between reconstructed and actual BP signals is 4.4797 mm Hg, which satisfies the American National Standards of the Association for the Advancement of Medical Instrumentation. The reconstructed BP waveform can be used to extract the SBP and DBP, whose standard deviations σ are 2.91 mm Hg and 2.41 mm Hg respectively.  相似文献   

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A Bloom filter is a space-efficient data structure used for concisely representing a set as well as membership queries at the expense of introducing false positive. In this paper, we propose the L-priorities Bloom filter (LPBF) as a new member of the Bloom filter (BF) family, it uses a limited multidimensional bit space matrix to replace the bit vector of standard bloom filters in order to support different priorities for the elements of a set. We demonstrate the time and space complexity, especially the false positive rate of LPBF. Furthermore, we also present a detailed practical evaluation of the false positive rate achieved by LPBF. The results show that LPBF performs better than standard BFs with respect to false positive rate.  相似文献   

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A simple yet effective state-estimation algorithm is presented and demonstrated to have advantages over previous standard clustering techniques used for the particle probability hypothesis density filter.The idea behind the proposed algorithm is that it uses the latest available information(i.e.,the measurements) to direct particle clustering.The particle likelihood and target number estimation,computed during probability hypothesis density recursion,are both used to partition particles into clusters,and the center of each cluster gives the state estimation of an individual target.Simulation results indicate that the proposed algorithm outperforms the standard clustering approach using the k-means algorithm,achieving higher accuracy and shorter computational time.  相似文献   

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Matth.  T 《计算机学报》2000,23(12):1235-1244
1 IntroductionThe interface between people and computershas progressed over the years from the early daysof switches and LEDs to punched cards,interactivecommand- line interfaces,and the directmanipula-tion style of graphical user interfaces.The“desk-top metaphor” of graphical user interfaces,a.k.a.WIMP interfaces (for Windows,Icons,Menus,and Pointing devices) ,has been the standard inter-face between people and computers for manyyears.Of course,software and technology for hu-man- compu…  相似文献   

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The International Telecommunications Union (ITU-T) and the International Standardization Organization/International Electrotechnical Commission (ISO/IEC) are the only two formal organizations that developed video coding standards. The ITU-T video coding standards called recommendations and are usually optimized for real-time video communication such as videoconference and video telephony while the ISO/IEC standards are mainly designed for storage (DVD) and broadcast (satellite and digital TV). ITU-T and the ISO/IEC JTC1 have agreed to join their efforts in the development of H.264 standard, which was initiated by ITU-T committee. The ITU-T H.264 video coding standard has been developed to achieve significant improvements over the existing standards in compression performance, although the basic coding framework of the standard is similar to that of the existing standards. H.264 standard is compared with H.263 and test results showed the coding gains obtained by the H.264 encoder is over the H.263 encoder for Common Intermediate Format (CIF) and Quarter Common Intermediate Format (QCIF)sequences, respectively. H.264 achieves an average of 4 dB PSNR(peak signal-to-noise rate) gain for the selected ten CIF sequences at 30 frames per second, and 4.57 dB Peak Signal-to-Noise Rate (PSNR) gain for the selected ten QCIF sequences at 30 frames per second.  相似文献   

11.
In this paper,a new method for fast direction-of-arrival(DOA) estimation with no dependance on array configurations is proposed,which is referred to as the symmetrical multiple signal classification(SMUSIC).Unlike the standard MUSIC,the S-MUSIC spatial spectrum is constructed by the intersection of the noise subspace and the conjugate noise subspace,and it hence generates spectral peaks at the true DOAs and the symmetrical virtual DOAs simultaneously.Such a characteristic allows fast DOA estimation by spectral search over only half of the total angular filed-of-view.Therefore,the new approach has a much lower computational complexity than the standard MUSIC.The statistical performance of S-MUSIC is studied and a close-form expression for the MSEs(mean square errors) of DOA estimation by the proposed estimator is derived.Numerical simulations are conducted to demonstrate the effectiveness of the new algorithm and to verify the theoretical analysis,and it is indicated that S-MUSIC makes a trade-off between MSEs and lower computational complexity as well as an improved resolution for closely-spaced sources as compared to the standard MUSIC.  相似文献   

12.
This paper presents a new optimized decentralized controller design method for solving the tracking and disturbance rejection problems for large-scale linear time-invariant systems, using only low-order decentralized controllers. To illustrate the type of results which can be obtained using the new optimized decentralized control design method, the control of a large flexible space structure is studied and compared with the standard centralized LQR-observer controller. The order of the resultant decentralized controller is much smaller than that of the standard centralized LQR-observer controller. The proposed controller also has certain fail-safe properties and, in addition, it can be five orders of magnitude more robust than the standard LQR-observer controller based on their real stability radii. The new decentralized controller design method is applied to a large flexible space structure system with 5 inputs and 5 outputs and of order 24.  相似文献   

13.
崔鹏  张承慧 《自动化学报》2007,33(6):635-640
The finite time horizon indefinite linear quadratic(LQ) optimal control problem for singular linear discrete time-varying systems is discussed. Indefinite LQ optimal control problem for singular systems can be transformed to that for standard state-space systems under a reasonable assumption. It is shown that the indefinite LQ optimal control problem is dual to that of projection for backward stochastic systems. Thus, the optimal LQ controller can be obtained by computing the gain matrices of Kalman filter. Necessary and sufficient conditions guaranteeing a unique solution for the indefinite LQ problem are given. An explicit solution for the problem is obtained in terms of the solution of Riccati difference equations.  相似文献   

14.
Ontologies are expected to play an important role in many application domains, as well as in software engineering in general. One problem with using ontologies within software engineering is that while UML, a widely used standard for specifying and constructing the models for a software-intensive system, has a four-layer metamodelling architecture, the standard Web Ontology Language (OWL) does not support reasoning over layered metamodels. OWL 2 provides simple metamodelling by using a punning approach, however, the interpretation function is different based on the context, which leads to non-intuitive results. The OWL FA Language has a well defined metamodelling architecture. However, there is no study and tool for supporting reasoning over OWL FA. In this paper, we discuss some reasoning tasks in OWL FA. We also introduce the OWL FA Tool kit, a simple tool kit for manipulating and reasoning with OWL FA.  相似文献   

15.
针对iSCSI SAN中现有的设备发现和管理方法所存在的问题,引入iSNS协议,研究并实现了iSNS协议在iSCSI中的应用,解决了存在的问题,并给出了简单的原型系统.  相似文献   

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W3C XML (Extensible Markup Language) Schema defines a set of abstract components, which carry the core semantics of document structure definition. There has been no standard API for accessing these components or their structures yet. The MARKUP Technology Company has specified a Java API for accessing XML Schema and submitted it to the W3C as a possible basis for standard Schema API. An overview of the schema API is provided and then XML schema serializer is implemented using this API in this paper.  相似文献   

18.
An innovative and uniform framework based on a combination of Gabor wavelets with principal component analysis (PCA) and multiple discriminant analysis (MDA) is presented in this paper. In this framework, features are extracted from the optimal random image components using greedy approach. These feature vectors are then projected to subspaces for dimensionality reduction which is used for solving linear problems. The design of Gabor filters, PCA and MDA are crucial processes used for facial feature extraction. The FERET, ORL and YALE face databases are used to generate the results. Experiments show that optimal random image component selection (ORICS) plus MDA outperforms ORICS and subspace projection approach such as ORICS plus PCA. Our method achieves 96.25%, 99.44% and 100% recognition accuracy on the FERET, ORL and YALE databases for 30% training respectively. This is a considerably improved performance compared with other standard methodologies described in the literature.  相似文献   

19.
The network-centric applied research team (N-CART) is continuing its work on an ambitious project known as the network-enabled powered wheelchair adaptor kit (NEPWAK). It introduces techniques for modifying and using powered wheelchairs as mobile platforms enabling communication and remote control. The wheelchair is equipped with a laptop computer, a CCD camera and a wireless network interface card (NIC) for 802.11b Internet access. The laptop acts as a server allowing network clients to gain access through a custom control interface on the chair. The remote controlling client receives a video and audio feed from the chair and sends control signals for maneuvering. While traveling, the chair is able to change its network association from one access point (AP) to another within the same subnet-the process is known as handoff. However, there is no inter-network handoff mechanism presently available in IP networks. This restricts the mobility of the wheelchair to within the coverage area of the subnet APs. This paper shows that the Internet engineering task force's (IETF) network layer mobility protocol-Mobile IP suffers from large handoff latencies that can hinder communication between the client and the wheelchair during handoff. Mobile IP alone is not a sufficient solution for a mobile telebotic system such as NEPWAK. An interesting solution to the handoff latency problem comes from the Fast-handover protocol described in Section 4.4 with simulation results in Section 6.2.  相似文献   

20.
The network-centric applied research team (N-CART) is continuing its work on an ambitious project known as the network-enabled powered wheelchair adaptor kit (NEPWAK). It introduces techniques for modifying and using powered wheelchairs as mobile platforms enabling communication and remote control. The wheelchair is equipped with a laptop computer, a CCD camera and a wireless network interface card (NIC) for 802.11b Internet access. The laptop acts as a server allowing network clients to gain access through a custom control interface on the chair. The remote controlling client receives a video and audio feed from the chair and sends control signals for maneuvering. While traveling, the chair is able to change its network association from one access point (AP) to another within the same subnet–the process is known as handoff. However, there is no inter-network handoff mechanism presently available in IP networks. This restricts the mobility of the wheelchair to within the coverage area of the subnet APs. This paper shows that the Internet engineering task force’s(IETF) network layer mobility protocol—Mobile IP[1] suffers from large handoff latencies that can hinder communication between the client and the wheelchair during handoff. Mobile IP alone is not a suffcient solution for a mobile telebotic system such as NEPWAK. An interesting solution to the handoff latency problem comes from the Fast-handover protocol[2] described in Section 4.4 with simulation results in Section 6.2.  相似文献   

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