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Signal Processing and Information Technology, 2005. Proceedings of the Fifth IEEE International Symposium on

Date 21-21 Dec. 2005

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Displaying Results 1 - 25 of 167
  • Welcome Message from the General Co-Chairs

    Page(s): i
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    Freely Available from IEEE
  • Organizing Committee

    Page(s): ii - iii
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    Freely Available from IEEE
  • Table of contents

    Page(s): iv - xx
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    Freely Available from IEEE
  • Budgeted region sampling (BeeRS): do not separate sampling from warm-up, and then spend wisely your simulation budget

    Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (653 KB) |  | HTML iconHTML  

    While the recent surge of research articles on sampling started with rather large sample sizes, it has later shifted to very small intervals, and it is now converging to intermediate sizes, and even to varying sizes. With 100M samples, warm-up is not an issue, at least with current cache sizes. However, with significantly smaller samples, warm-up becomes critical, especially when the sampling target accuracy is of the order of a few percent. However, in most sampling research works, warm-up has largely been treated as a separate issue. In this article, we advocate for an integrated approach at (simulator-based) warm-up and sampling. Instead of separating warm-up and sampling, we take exactly the opposite approach, provide a common instruction budget for warm-up and sampling, and we attempt to spend it as wisely as possible on either one. This budget and integrated approach at warm-up and sampling achieves an average CPI error of 1.68% on the 26 Spec benchmarks with an average sampling size of 288 millions instructions, and at the same time, it relieves the user from any delicate decision such as setting the sampling or warm-up sizes, thanks to the integrated warm-up+sampling and the region partitioning approaches View full abstract»

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  • DIABLO: a reliable, retargetable and extensible link-time rewriting framework

    Page(s): 7 - 12
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (326 KB) |  | HTML iconHTML  

    Modern software engineering techniques introduce an overhead to programs in terms of performance and code size. A traditional development environment, where only the compiler optimizes the code, cannot completely eliminate this overhead. To effectively remove the overhead, tools are needed that have a whole-program overview. Link-time binary rewriting is an effective technique for whole-program optimization and instrumentation. In this paper, we describe a novel framework to reliably perform link-time program transformations. This framework is designed to be retargetable, supporting multiple architectures and development toolchains. Furthermore it is extensible, which we illustrate by describing three different applications that are built on top of the framework. View full abstract»

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  • Understanding the performance of concurrent error detecting superscalar microarchitectures

    Page(s): 13 - 18
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (247 KB) |  | HTML iconHTML  

    Superscalar out-of-order micro architectures can be modified to support redundant execution of a program as two concurrent threads for soft-error detection. However, the extra workload from redundant execution incurs a performance penalty due to increased contention for resources throughout the datapath. We present four key parameters that affect performance of these designs, namely 1) issue and functional unit bandwidth, 2) issue queue and reorder buffer capacity, 3) decode and retirement bandwidth, and 4) coupling between redundant threads' instantaneous resource requirements. We then survey existing work in concurrent error detecting superscalar micro architectures and evaluate these proposals with respect to the four factors View full abstract»

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  • Toward a processor core for real-time capable autonomic systems

    Page(s): 19 - 22
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (226 KB) |  | HTML iconHTML  

    This paper proposes a processor core that allows to support the autonomic computing principles in embedded hard-real-time systems. The simultaneous multithreaded CAR-core processor features hardware-integrated scheduling schemes that isolate the hard-real-time thread from non-real-time threads. It is binary compatible with Infineon's TriCore processor and designed as IP core for a system-on-chip. The challenge for the processor design is to implement simultaneous multithreading such that a thread cannot influence the timing behavior of another thread in order to allow predictable thread execution times. Therefore new instruction issue and data memory access techniques are proposed. The autonomic computing requirements shall be implemented by autonomic managers running as helper threads in own thread slots concurrent to the real-time application. The autonomic manager threads monitor the application and decide if self-configuration, self-healing, self-optimization, or self-protection must be triggered View full abstract»

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  • A DNA sequence compression algorithm based on LUT and LZ77

    Page(s): 23 - 28
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (142 KB) |  | HTML iconHTML  

    This article introduces a new DNA sequence compression algorithm which is based on LUT and LZ77 algorithm. Combined a LUT-based preceding routine and LZ77 compression routine, this algorithm can approach a compression ratio of 1.9 bits/base and even lower. The biggest advantage of this algorithm is fast execution, small memory occupation and easy implementation View full abstract»

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  • Gene classification and regulatory prediction based on transcriptional modeling

    Page(s): 29 - 34
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1279 KB) |  | HTML iconHTML  

    We present a methodology that aims to elucidate regulatory mechanisms by grouping together genes which share the same regulatory network. In our method, we use multi-state partition functions and thermodynamic models to derive six distinct correlation classes that correspond to various protein-protein and protein-DNA interactions. We then introduce a novel biclustering algorithm that clusters together genes whose expression profiles exhibit the derived correlations in various conditions. The functional enrichment and statistical significance of the resulting clusters is evaluated by precision-recall curves and calculated p-values. Moreover, we analyzed the upstream regions of all genes that comprise each cluster, in order to verify that the derived correlation classes capture the expression of genes with common regulation. We have been able to identify over hundred strongly conserved sequences, among which eight match well-known regulatory motifs. Finally, further analysis of the identified conserved sequences provides not only an explanation of the classification performance, but serves also as an indicator of the regulatory coherence of various groups View full abstract»

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  • Biological significance of a novel biclustering technique on genetic expression data

    Page(s): 35 - 39
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (385 KB) |  | HTML iconHTML  

    Unlocking the complexity of a living organism's biological processes, functions, and genetic network is vital in learning how to improve the health of humankind. Genetic analysis, especially biclustering, is a significant step in this process. Learning how genes function together in groups, how they regulate under different conditions, and what proteins created by genes trigger certain biological processes will pave new pathways for genetic engineering and disease therapy. This experiment analyzes one such biclustering technique that combs over a gene expression matrix to find subgroups of genes with coherent evolution, that is genes whose expression levels stay constant or increase coherently over a subgroup of conditions or samples. This biclustering technique was applied to an S. cervisiae, or yeast, genetic expression data matrix. The biclustering was again performed on the same initial matrix two more times, each with selected genes omitted with the intent to increase the biological correlation relationship of the genes in the resultant biclusters. The final results were analyzed using a categorized system of known protein functional annotation from the yeast genome to find the biological significance of the submatrices detected by the algorithm View full abstract»

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  • BIO101 - EST sequence management and annotation system

    Page(s): 40 - 45
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    Laboratories worldwide are working on EST cDNA library and microarray projects, each project involving hundreds to hundreds of thousands of clones. To support the needs of individual laboratories, an efficient EST sequence management system is needed. Here, we describe BIO101, a centralized approach to laboratory EST sequence management and functional annotation. The system includes a) laboratory-based authorization, project-focused and custom database management features; b) a pipeline with integrated tools for producing and clustering high-quality ESTs and for identifying homologues; c) a pipeline scheduling mechanism that emphasizes fairness; and d) collaborative manual and automatic functional annotation features. BIO101 is accessible to registered members at http://bio101.iis.sinica.edu.tw/ View full abstract»

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  • A biophysical model of the human cochlea for speech stimulus using STFT

    Page(s): 46 - 50
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (613 KB) |  | HTML iconHTML  

    This paper presents a new approach to an auditory model which matches closely the response patterns in physiological data for single tone inputs. Including the biophysical complexity of the wave motion in the cochlea and considering all terms of the motion equation, the new model can evaluate the auditory spectrum using the Basilar membrane (BM) displacement and the inner hair cells' (IHCs) firing rate for all input signals, including speech. We employ the partial differential motion equations of the BM and its parameters measured for the human auditory system, and design an algorithm which uses short time Fourier transform (STFT) to compute the output for speech stimulus. The idea is to isolate the input signal in the vicinity of a time-window and try to follow the changes in its frequencies and their influences on the signal perceived by the auditory system. The new model includes the nonlinearity action of outer hair cells (OHCs) and provides a new auditory spectrum for speech inputs in the real time domain which reflects a proper view of propagating signal in the cochlea. Despite most of the previous models this model can track the effects of high formant frequencies in the human cochlea as well. This model is a new signal processing tool for studying the response of the auditory system to transient signals which is highly demanded in various speech enhancement and audio coding algorithms View full abstract»

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  • Time-frequency approach for analysis and synthesis of particular emotional voice

    Page(s): 51 - 56
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1203 KB) |  | HTML iconHTML  

    In this paper, the analysis and synthesis methods of particular emotional voice for man-machine natural interface is developed. First, the emotional voice (neutral, anger, sadness, joy, dislike) is analyzed using time-frequency representation of speech and similarity analysis. Then, based on the result of emotional analysis, a voice with neutral emotion is transformed to synthesize the particular emotional voice using time-frequency modifications. In the simulations, five types of emotion are analyzed using 50 samples of speech signals. The satisfactory average discrimination rate is achieved in the similarity analysis. Further, the synthesized emotional voice is subjectively evaluated. It is confirmed that the emotional voice is naturally generated by the proposed time-frequency based approach View full abstract»

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  • Zipf, neural networks and SVM for musical genre classification

    Page(s): 57 - 62
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (295 KB) |  | HTML iconHTML  

    We present in this paper audio classification schemes that we have experimented in order to perform musical genres classification. This type of classification is a part of a more general domain which is automatic semantic audio classification, the applications of which are more and more numerous in such fields as musical or multimedia databases indexing. Experimental results have shown that the feature set we have developed, based on Zipf laws, associated with a combination of classifiers organized hierarchically according to classes taxonomy allow an efficient classification View full abstract»

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  • 2D spatial-frequency processing based audio coding for real time wireless transmission

    Page(s): 63 - 68
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (451 KB) |  | HTML iconHTML  

    Wireless systems are often subject to bandwidth or cost constraints which are incompatible with high data rates. The key enabling technology for digital audio wireless products is data compression. For real time wireless transmission, very low encoding and decoding delay has become an essential prerequisite. In live productions, the tolerable total delay time is less than a few milliseconds. Current audio coding schemes like MPEG standards or wavelet techniques can hardly reach such a threshold by using overlapping frames of input signal with psychoacoustic model. This paper presents a two dimensional (2D) spatial-frequency processing based audio coder with ultra low delay for real time wireless applications using non-overlapping short block processing and embedded coding. 2D fast lifting wavelet transform with boundary effects minimized is developed for further exploring the correlation of the audio signal. A modified 2D SPIHT (set partitioning in hierarchical trees) algorithm with more bits used to encode the wavelet coefficients and transmitting fewer bits in the sorting pass, is implemented to reduce the correlation between the coefficients at different decomposition levels and inside each band at scalable bit rates. The experiment shows the proposed coder is efficient and has low complexity with less memory requirements in implementation View full abstract»

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  • Scheduling stochastic tasks with parallelizable contents in multiprocessor systems

    Page(s): 69 - 75
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (222 KB) |  | HTML iconHTML  

    In this paper, we present a new heuristic algorithm to schedule a set of independent stochastic tasks with parallelizable contents in multiprocessor systems. Each task is described by its deadline and its time cost distribution, which is given in terms of mean and variance. A scheduled task may run as one unit on a single processor or partitioned into k parallel parts running on k different processors. The proposed algorithm exploits parallelism in tasks, if it is necessary, and distributes them among the available processors to yield a high probability of meeting their deadlines and, hence obtain better schedulability View full abstract»

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  • Efficient processing power utilization to execute real-time tasks

    Page(s): 76 - 81
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (252 KB) |  | HTML iconHTML  

    Scheduling real-time applications requires high utilization of the available processing power on processors to accommodate as many tasks as possible while satisfying the required deadlines of the applications. Moreover, an acceptable level of reliability should be provided due to the critical nature of the applications. In this paper, we propose a new approach that highly utilizes the available processing power to improve the admission rate of real-time task scheduling. The basic idea is to use all of the available processing power to execute allocated tasks. This reduces the execution time needed for each task and hence increases its reliability. It also reduces needed processing power for existing tasks to satisfy their deadlines and hence provides higher available processing power for any new task. This gives a higher chance for the new arriving task to be accommodated. We show that our approach is beneficial in that it provides a better scheme with higher acceptance rate for real time tasks compared to the traditional approach of using a fixed processing power reservation View full abstract»

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  • Performance evaluation of modified hierarchical ring by exploiting link utilization and memory access locality

    Page(s): 82 - 87
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (442 KB) |  | HTML iconHTML  

    In multiprocessor systems, the interconnection network design is critical for overall system performance. In this paper, we show the modified hierarchical ring network, called as Torus ring, and deeply evaluate the performance of the Torus ring. The Torus ring has an advantage over the hierarchical ring when the destination of network packet is the adjacent local ring, especially to the backward direction, by exploiting the memory access locality. Further, the performance gain of the Torus ring is expected to increase, due to the spatial locality of the applications and the efficient utilization of link bandwidth. In the simulation results, the overall execution time of Torus ring is reduced, up to 4.5% with moderate ring utilization ratios, compared to the hierarchical ring View full abstract»

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  • Performance-energy trade-off exploration in dynamic data types for network applications

    Page(s): 88 - 93
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (273 KB) |  | HTML iconHTML  

    Demanding applications are introduced to networking field, asking simultaneously for high performance and low-energy consumption, requests more imperative in wireless networks. The dynamic nature of such applications makes the dynamic memory subsystem of an embedded system a critical contributing factor to the overall energy and execution time performance. This paper presents a novel aspect in designing dynamic data types in network applications. A systematic methodology, which is tool-supported and capable of manipulating different network traces, is proposed. Plethora of possible solutions, i.e. Pareto points, in terms of energy consumption, performance and memory size usage is achieved. Eventually, alternative optimal implementations, i.e. Pareto-optimal points can be extracted. Two real-life case studies (from NetBench suite) are studied and explored thoroughly. It is proved that up to 80% energy savings and up to 20% performance, comparing with two benchmarks' original implementation, can be accomplished. Furthermore, a plethora of trade-offs among the Pareto-optimal choices reach up to 52% for energy consumption and up to 13% for performance, are achieved View full abstract»

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  • SchedSP-WS: adaptation of an application service platform for scheduling solutions to Web services and grid standards

    Page(s): 94 - 98
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (419 KB) |  | HTML iconHTML  

    This paper describes the architecture and design evolution of an application-specific service platform following the Web services and grid related developments. The adoption of Web services standards for the various components of a scheduling service provider named SchedSP-WS is the main contribution of this paper. The use of grid standards for the seamless integration of the service provider and the computational infrastructure is also presented View full abstract»

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  • Effect of measurement error on the capacity of a MIMO wireless system

    Page(s): 99 - 103
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (232 KB) |  | HTML iconHTML  

    A multiple-input/multiple-output (MIMO) communications system model is described with reference to antenna measurements from a microwave network analyser. Results are presented which indicate the effect of a measurement error in a MIMO communications system. These results offer an indication of the degree of measurement accuracy required for a MIMO communications system to be a viable alternative to a conventional antenna communications system View full abstract»

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  • Improved single PARAFAC decomposition based blind MIMO system estimation

    Page(s): 104 - 108
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (266 KB) |  | HTML iconHTML  

    We consider the problem of frequency domain identification of a multiple-input multiple-output (MIMO) system driven by white, mutually independent unobservable inputs. In particular, we improve upon a method recently proposed by the authors that uses PARAFAC decomposition of a tensor that is formed based on higher-order statistics of the system output. The approach of Y. Yu and A.P. Petropulu, 2005, utilizes only one slice of the output tensor to recover one row of the system response matrix. We proposed an approach that fully exploits the information in the output tensor, and as a result achieves lower error values. The proposed modification renders the method applicable to systems with more inputs than outputs View full abstract»

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  • On space-time block coding in downlink of multiuser CDMA systems

    Page(s): 109 - 112
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (195 KB) |  | HTML iconHTML  

    In this paper, we introduce a new transmission scheme for downlink of multiple antenna code division multiple access (CDMA) systems. In the proposed scheme, the Alamouti's space-time block coding (STBC) method is extended to multiuser systems. Moreover, to mitigate multiple access interference in the conventional receivers, the linear transmit preceding technique is used in the transmitter. We show that using STBC codes in conjunction with transmit preceding in CDMA systems can significantly increase the capacity of these systems. In this method, the mobile terminals are simple and they do not need any information about other users' spreading sequences. Our computer simulations show that the proposed method has the same performance as the methods based on the combination of receive diversity and multiuser detection in the uplink of CDMA systems View full abstract»

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  • A multicarrier CDMA system for combating channel blocking in frequency-selective fading MIMO channel

    Page(s): 113 - 118
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    Recently we have proposed a multi-carrier code division multiple access (MC-CDMA) scheme for the downlink of mobile communications to combat the channel blocking in flat fading multi-input single-output (MISO) channels. In this paper, the previous proposal is extended to the case of frequency-selective fading multi-input multi-output (MIMO) channels. An enhanced scheme is also proposed to obtain better bit error rate (BER) performance and to facilitate signal detection. BER performance of the proposed system using different detection methods is evaluated by numerical calculation. Without decreasing time, frequency, and transmit (Tx) power efficiencies, the proposed system allows us to extract all the Tx data with relatively good BER even when channel blocking is encountered View full abstract»

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  • Prediction of the eigenvectors for spatial multiplexing MIMO systems in time-varying channels

    Page(s): 119 - 124
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (664 KB) |  | HTML iconHTML  

    In mobile communications, time varying channels make the available channel information out of date. Timely updating the channel state is an obvious solution to improve the system performance in a time varying channel. However, a better knowledge of the channel comes at the cost of a decrease in the system throughput. Thus, predicting the future channel conditions can improve not only the performance but also the throughput of many types of wireless systems. This is especially true for a wireless system where multiple antennas are applied at both link ends. In this paper we propose and evaluate the performance of a prediction scheme for multiple input multiple output (MIMO) systems that apply spatial multiplexing. We aim at predicting the future precoder/decoder directly without going through the prediction of the channel matrix. The results show that in a slowly time varying channel an increase in the system performance by a factor of two is possible View full abstract»

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