A component-based UML profile is built to develop embeddedreal-timesystems. To specify the specific characteristics of embeddedsystems, the Model Driven Architecture (MDA) approach and component-based modeling are ...
详细信息
Since high-quality image/video systems based on the JPEG/MPEG compression standards often require power-expensive implementations at relatively high bit-rates, they have not been widely used in low-power wireless appl...
详细信息
ISBN:
(纸本)0769523463
Since high-quality image/video systems based on the JPEG/MPEG compression standards often require power-expensive implementations at relatively high bit-rates, they have not been widely used in low-power wireless applications. To alleviate this problem, we designed, implemented, and evaluated a strategy that can adapt to different compression and transmission rates. (1) It gives important parts of an image higher priority over unimportant parts. therefore, the high-priority parts can achieve high image quality, while the low-priority parts, with a slight sacrifice of quality, can achieve huge compression rate and thus save the power/energy of a low-power wireless system. (2) We also introduce a priority-driven scheduling approach into our coding algorithm, which makes the transmission of important parts earlier with more data than other parts. through a balanced trade-off between the available time/bandwidth/power and the image quality, this adaptive strategy can satisfy users with desired images quality and lead to a significant reduction of the important parts' deadline misses.
this paper presents an efficient technique for placement and routing of sensors/actuators and processing units in a grid network. the driver application that we present is a medical jacket which requires an extremely ...
详细信息
ISBN:
(纸本)0769523463
this paper presents an efficient technique for placement and routing of sensors/actuators and processing units in a grid network. the driver application that we present is a medical jacket which requires an extremely high level of robustness and fault tolerance. the power consumption of such jacket is another key technological constraint. Our proposed interconnection network is a mesh of wires. A jacket made of fabric and wires would be susceptible to accidental damage via tears. By modeling the tears, we evaluate the probability of having failures on every segment of wires in our mesh interconnection network. then we study two problems of placement and routing in the sensor networks such that the fault tolerance is maximized while the power consumption is minimized. We develop efficient integer linear programming (ILP) formulations to address these problems and perform both placement and routing simultaneously. this ensures that the solution is a lower bound for both problems. We evaluate the effectiveness of our proposed techniques on a variety of benchmarks.
Common Language Infrastructure (CLJ) has been introduced as a core technology of Microsoft .NET. It enables "writing in multiple languages, running in multiple platforms" by providing Virtual Execution Syste...
详细信息
Priorities are used to resolve conflicts such as in resource sharing and in safety designs. the use of priorities has become indispensable in real-time system design such as in scheduling, synchronization, arbitration...
详细信息
Recently, a new class of data-intensive applications has received wide attention. In these applications, monitoring functions can be performed by executing pre-registered transactions periodically using data from exte...
详细信息
ISBN:
(纸本)0769523463
Recently, a new class of data-intensive applications has received wide attention. In these applications, monitoring functions can be performed by executing pre-registered transactions periodically using data from external sources in the form of continuous data streams and producing updates as temporal data in the database. For this type of continuous transactions, the data access pattern has to be declared before submission. To keep the database fresh, these transactions must be processed in a timely fashion. However it is also desirable to execute other one-time transactions that may use these temporal data within their deadlines. Traditional DBMS are not designed to support such applications. the theme of this work is to propose new concurrency control protocols to process these types of transactions with competing requirements. the challenge of this work is to balance database freshness and transaction performance. Although there is a number of similar previous works in the literature, they did not consider the presence of continuous transactions and therefore the issue of data dependency between these two types of transactions is not addressed. the simulation results show that our protocols can significantly improve the performance of one-time transactions while keeping the database fresh.
On-demand broadcast is an attractive data dissemination method for mobile and wireless computing. In this paper, we propose a new online preemptive scheduling algorithm, called PRDS that incorporates the urgency, the ...
详细信息
there are many trials to provide an optimal route for minimum energy consumption in a wireless sensor network. Currently, however, the mechanisms to find Minimum Energy Property Graph (MEPG) do not properly take into ...
详细信息
As a result of development of embedded system, the concept of embedded system is improved from "the computer system embedded in large system" to "the system completing independent functions." At fi...
详细信息
ISBN:
(纸本)9812565329
As a result of development of embedded system, the concept of embedded system is improved from "the computer system embedded in large system" to "the system completing independent functions." At first, the many application instances of embeddedsystems are listed, including the fields of aviation, aerospace, military affairs, vehicle embedded, communication, the main features of application environment of embedded system are given. then, a survey of popular embedded operating systems is presented. And then the future trends of embedded system are analyzed from three aspects: open & standard & COTS;real-time & reliability & security computing capability & application environment. Finally, the main research topics of embedded system are given.
In this paper, we propose a new approach for efficient and real-time tracking of the moving objects in sensor networks by mining the movement log. In our approach, we first conduct the hierarchical clustering to form ...
详细信息
暂无评论