Low-power design is one of the most important issues in wireless sensor networks (WSNs) , while reliable information transmitting should be ensured as well. Transmitting power (TP) control is a simple method to make t...
详细信息
Low-power design is one of the most important issues in wireless sensor networks (WSNs) , while reliable information transmitting should be ensured as well. Transmitting power (TP) control is a simple method to make the power consumption down, but excessive interferences from potential adjacent operating links and communication reliability between nodes should be considered. In this paper, a reliable and energy efficient protocol is presented, which adopts adaptive rate control based on an optimal TP. A mathematical model considering average interference and network connectivity was used to predict the optimal TP. Then for the optimal TP, active nodes adaptively chose the data rate with the change of bit-error–rate(BER) performance. The efficiency of the new strategy was validated by mathematical analysis and simulations. Compared with 802.11 DCF which uses maximum unified TP and BASIC protocol, it is shown that the higher average throughput can achieve while the energy consumption per useful bit can be reduced according to the results.
In recent years, China has witnessed considerable achievements in the production of domesticallydesigned CPUs and DSPs. Owing to fifteen years of hard work that began in 2001, significant progress has been made in Chi...
详细信息
In recent years, China has witnessed considerable achievements in the production of domesticallydesigned CPUs and DSPs. Owing to fifteen years of hard work that began in 2001, significant progress has been made in Chinese domestic CPUs and DSPs, primarily represented by Loongson and Shen Wei *** parts of the CPU design techniques are comparable to the world’s most advanced designs. A special issue published in Scientia Sinica I nf ormationis in April 2015, is dedicated to exhibiting the technical advancements in Chinese domestically-designed CPUs and DSPs. The content in this issue describes the design and optimization of high performance processors and the key technologies in processor development; these include high-performance micro-architecture design, many-core and multi-core design, radiation hardening design, highperformance physical design, complex chip verification, and binary translation technology. We hope that the articles we collected will promote understanding of CPU/DSP progress in China. Moreover, we believe that the future of Chinese domestic CPU/DSP processors is quite promising.
As semiconductor technology advances, there will be billions of transistors on a single chip. Chip many-core processors are emerging to take advantage of these greater transistor densities to deliver greater performan...
详细信息
As semiconductor technology advances, there will be billions of transistors on a single chip. Chip many-core processors are emerging to take advantage of these greater transistor densities to deliver greater performance. Effective fault tolerance techniques are essential to improve the yield of such complex chips. In this paper, a core-level redundancy scheme called N+M is proposed to improve N-core processors’ yield by providing M spare cores. In such architecture, topology is an important factor because it greatly affects the processors’ performance. The concept of logical topology and a topology reconfiguration problem are introduced, which is able to transparently provide target topology with lowest performance degradation as the presence of faulty cores on-chip. A row rippling and column stealing (RRCS) algorithm is also proposed. Results show that PRCS can give solutions with average 13.8% degradation with negligible computing time.
Genomic sequence comparison algorithms represent the basic toolbox for processing large volume of DNA or protein sequences. They are involved both in the systematic scan of databases, mostly for detecting similarities...
详细信息
The quantity of computer applications is increasing dramatically as the computer industry prospers. Meanwhile, even for one application, it has different requirements of performance and power in different scenarios. A...
详细信息
The quantity of computer applications is increasing dramatically as the computer industry prospers. Meanwhile, even for one application, it has different requirements of performance and power in different scenarios. Although various processors with different architectures emerge to fit for the various applications in different scenarios, it is impossible to design a dedicated processor to meet all the requirements. Furthermore, dealing with uncertain processors significantly aggravates the burden of programmers and system integrators to achieve specific performance/power. In this paper, we propose elastic architecture (EA) to provide a uniform computing platform with high elasticity, i.e., the ratio of worst-case to best-case performance/power/performance-power trade-off, which can meet different requirements for different applications. It is achieved by dynamically adjusting architecture parameters (instruction set, branch predictor, data path, memory hierarchy, concurrency, status^zcontrol, and so on) on demand. The elasticity of our prototype implementation of EA, as Sim-EA, ranges from 3.31 to 14.34, with 5.41 in arithmetic average, for SPEC CPU2000 benchmark suites, which provides great flexibility to fulfill the different performance and power requirements in different scenarios. Moreover, Sim-EA can reduce the EDP (energy-delay product) for 31.14% in arithmetic average compared with a baseline fixed architecture. Besides, some subsequent experiments indicate a negative correlation between application intervals' lengths and their elasticities.
Network-on-Chip (NoC) with excellent scalability and high bandwidth has been considered to be the most promising communication architecture for complex integration systems. However, NoC reliability is getting contin...
详细信息
Network-on-Chip (NoC) with excellent scalability and high bandwidth has been considered to be the most promising communication architecture for complex integration systems. However, NoC reliability is getting continuously challenging for the shrinking semiconductor feature size and increasing integration density. Moreover, a single node failure in NoC might destroy the network connectivity and corrupt the entire system. Introducing redundancies is an efficient method to construct a resilient communication path. However, prior work based on redundancies, either results in limited reliability with coarse grain protection or involves even larger hardware overhead with fine grain. In this paper, we notice that data path such as links, buffers and crossbars in NoC can be divided into multiple identical parallel slices, which can be utilized as inherent redundancy to enhance reliability. As long as there is one fault-free slice left available, the proposed salvaging scheme named as RevivePath, can be employed to make the overall data path still functional. Furthermore, RevivePath uses the direct redundancy to protect the control path such as switch arbiter, routing computation, to provide a full fault-tolerant scheme to the whole router. Experimental results show that it achieves quite high reliability with graceful performance degradation even under high fault rate.
As the gap between processing capability and bandwidth requirement of microprocessor increases, optical interconnects are used more and more widely in chip-to-chip data links. Trade-offs are made among latency, area, ...
详细信息
The wide application of General Purpose Graphic Processing Units (GPGPUs) results in large manual efforts on porting and optimizing algorithms on them. However, most existing automatic ways of generating GPGPU code fa...
详细信息
The task of detecting fraud in credit card transactions is crucial to ensure the security and stability of a financial system, as well as to enforce customer confidence in digital payment systems. Historically, credit...
详细信息
Machine-learning techniques have recently been proved to be successful in various domains, especially in emerging commercial applications. As a set of machine- learning techniques, artificial neural networks (ANNs),...
详细信息
Machine-learning techniques have recently been proved to be successful in various domains, especially in emerging commercial applications. As a set of machine- learning techniques, artificial neural networks (ANNs), requiring considerable amount of computation and memory, are one of the most popular algorithms and have been applied in a broad range of applications such as speech recognition, face identification, natural language processing, ect. Conventionally, as a straightforward way, conventional CPUs and GPUs are energy-inefficient due to their excessive effort for flexibility. According to the aforementioned situation, in recent years, many researchers have proposed a number of neural network accelerators to achieve high performance and low power consumption. Thus, the main purpose of this literature is to briefly review recent related works, as well as the DianNao-family accelerators. In summary, this review can serve as a reference for hardware researchers in the area of neural networks.
暂无评论