The indoor distributed tracking system proposed in this paper is a client-server architecture with three basis subsystems:the site information server,mobile units,and the network *** tracking process is divided into f...
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The indoor distributed tracking system proposed in this paper is a client-server architecture with three basis subsystems:the site information server,mobile units,and the network *** tracking process is divided into four procedures:camera pose computing,2D features tracking, 2D-3D correspondence and natural feature *** achieve real-time behavior required for tracking applications, dynamic interpretation tree is used to organize data in a multimedia object *** computations of 2D image registration for pose estimation are done on basis of the Fast Fourier Transform because of its robustness and fast *** track camera pose and dynamically estimate the 3D positions of natural feature,we use an auto-calibration approach based on an iterative Extended Kalman *** result shows that our system can successfully provide indoors mobile users with 3D positions from 2D image points and information of augmented reality.
Today, Windows/spl reg/-based (and UNIX/spl reg/-based) PCs have ability to access to the networks at anytime and anyplace. The benefit of such an "always-connected" environment is expanded to non-PC users w...
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ISBN:
(纸本)0769519288
Today, Windows/spl reg/-based (and UNIX/spl reg/-based) PCs have ability to access to the networks at anytime and anyplace. The benefit of such an "always-connected" environment is expanded to non-PC users with new consumer products such as Airboard and CoCoon, which we call the network electronics (or NE) products in this paper.
The paper outlines the design and implementation of the realtime Application Interface (RTAI) for Linux, as used for high performance local/distributed control systems implemented on low cost off the shelf general pu...
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ISBN:
(纸本)0769519288
The paper outlines the design and implementation of the realtime Application Interface (RTAI) for Linux, as used for high performance local/distributed control systems implemented on low cost off the shelf general purpose computers. Its native lean realtime middleware layer is described along with its use in an advanced tool to easily manage and monitor complex networked control systems.
The paper describes design and implementation of software infrastructure for building augmented reality applications for ubiquitous computing environments. Augmented reality, is one of the most important techniques to...
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ISBN:
(纸本)0769519288
The paper describes design and implementation of software infrastructure for building augmented reality applications for ubiquitous computing environments. Augmented reality, is one of the most important techniques to achieve the vision of ubiquitous computing. Traditional toolkits for aligmented reality provide the high level abstraction that makes it easy to but. Id augmented reality, applications. However, the applications programmers need to contemplate distribution and context-awareness that make the development of applications very hard, but they are necessary to build ubiquitous computing environments. Our infrastructure provides the high level abstraction and hides distribution and con text-awareness from programmers. Therefore, the cost to develop augmented reality applications will be reduced dramatically by using our middleware infrastructure.
Structuring real-time concurrent programs in the form of groups of fixed-priority processes is an old art which is appropriate for only a small fraction of modem real-timedistributedcomputing application systems. Ho...
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ISBN:
(纸本)0769519288
Structuring real-time concurrent programs in the form of groups of fixed-priority processes is an old art which is appropriate for only a small fraction of modem real-timedistributedcomputing application systems. However, it is still practiced on the basis of an insufficient technical foundation. One of the basic issues in using the fixed-priority process structuring approach is to avoid the priority inversion phenomenon. It is argued that priority inversions are essentially due to the inappropriate approach used for structuring programs including the specification of the policy for allocating resources. Several basic program structuring techniques which are effective means of avoiding priority inversions are presented.
Primus Epic(TM) is an all-new integrated avionics system for business, regional and general aviation. Honeywell international Inc. follows the objectoriented paradigm and the programming language C++ for certain soft...
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ISBN:
(纸本)0769519288
Primus Epic(TM) is an all-new integrated avionics system for business, regional and general aviation. Honeywell international Inc. follows the objectoriented paradigm and the programming language C++ for certain software components on systems developed for the PRIMUS EPIC system. While C++ programming language offers several advantages, it also has several features that can make it undesirable for use in airborne systems. The object Orientation concept has several features that, if not controlled properly, can lead to unknown configurations of object code and unverified code. This is highly undesirable for avionics software that needs certification involving statement and code coverage. This paper highlights the issues with C++ certification for avionics and provides solutions for some of the issues.
distributed control systems (DCSs) consisting of a plant, a controller composed of many devices, and an open network interconnecting devices, are now used in many automation areas. For assuring the control performance...
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ISBN:
(纸本)0769519288
distributed control systems (DCSs) consisting of a plant, a controller composed of many devices, and an open network interconnecting devices, are now used in many automation areas. For assuring the control performance under the heavy traffic on the network, the simulation of DCS is strongly needed. In the case of DCSs for controlling a mechanical plant, the graphical and cooperative simulation between the controller model and the plant model becomes important to verify the sequence of motions of the plant. For this purpose, we propose a systematic object-oriented-based DCS modeling procedure to efficiently and uniformly develop the DCS simulation model. From this procedure, we can describe the formal description of DCS simulation model based on five object-oriented design patterns which describe the structure and behavior of the DCS. We also propose an event chain mechanism between the statechart-based controller model and the graphical plant model. Finally, the cooperative DCS simulation software is developed by! using the Java 3D API.
In this paper, we present a systems engineering methodology for constructing certifiable real-timedistributed systems. In the proposed approach, an architectural and algorithmic solution to an application problem is ...
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ISBN:
(纸本)0769519288
In this paper, we present a systems engineering methodology for constructing certifiable real-timedistributed systems. In the proposed approach, an architectural and algorithmic solution to an application problem is designed by considering the "'weakest" models including the weakest asynchronous computational model and multimodal arrival model. Furthermore, timeliness properties are described using Jensen's benefit accrual predicates. Once a system solution is designed, timeliness properties are established by constructing necessary feasibility conditions that are expressed as non-valued predicates. The predicates are quantified and verified to produce the specification of a certified solution. We illustrate the approach by considering a packet transmission problem that desire soft timeliness. We present a certifiable solution to this problem that consists of switched Ethernet, a soft real-time packet scheduling algorithm (that was previously developed), and feasibility conditions.
We discuss how to invoke a method on multiple object replicas in a quorum-based way. Suppose each instance of a method t on replicas of an object x invokes another method u on replicas in a quorum of an object y. Here...
ISBN:
(纸本)0769519288
We discuss how to invoke a method on multiple object replicas in a quorum-based way. Suppose each instance of a method t on replicas of an object x invokes another method u on replicas in a quorum of an object y. Here, the method u is redundantly invoked multiple times on some replicas of the object y. If each instance of the method t issues a method to its own quorum, more number of replicas are manipulated than the quorum number This is quorum expansion. We discuss a protocol to invoke methods on replicas in a nested manner without the redundant invocation and quorum expansion. We evaluate the protocol on how many replicas are manipulated and requests are issued.
Devices in ubiquitous computing environments are usually embedded, wearable, and handheld, have resource constraints, and are all connected to each other through wireless connections and other computers possibly throu...
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ISBN:
(纸本)0769519288
Devices in ubiquitous computing environments are usually embedded, wearable, and handheld, have resource constraints, and are all connected to each other through wireless connections and other computers possibly through fixed network infrastructures, such as the Internet. These devices may form numerous webs of short-range and often low-power mobile ad hoc networks to exchange information. distributedobjectcomputing (DOC) middleware technologies have been successful in promoting high quality and reusable distributed software for enterprise-oriented environments. In order to reap the same benefit in ubiquitous computing environments, it is important to note that the natural interactions among distributedobjects in ubiquitous computing environments are quite different due to various factors, such as bandwidth constraints, unpredictable device mobility, network topology change, and context-sensitivity (or situation-awareness) of application objects. Hence, the interactions among distributedobjects tend to be more spontaneous and short-lived rather than predictable and long-term. In this paper, a middleware protocol, RKF, to facilitate distributedobject-based application software to interact in an ad hoc fashion in ubiquitous computing environments is presented. RKF addresses both spontaneous object discovery and context-sensitive object data exchange. Our experimental results, based on RKF's implementation and evaluation inside the object request broker of our RCSM middleware test bed, indicate that it is lightweight, has good performance, and can be easily used in PDA-like devices.
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