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The article explores power control opportunities in a general dynamic-compilation environment for microprocessors. A dynamic compiler is a runtime software system that compiles, modifies, and optimizes a program's instruction sequence as it runs. Beyond regular performance optimizations, a dynamic compiler can also apply energy optimizations such as dynamic voltage and frequency scaling (DVFS) because most DVFS implementations allow direct software control through mode set instructions. A design framework for a run-time DVFS optimizer (RDO) in a dynamic-compilation environment has been developed. The RDO instruments all function calls in the program and all loops in the main function to monitor and identify frequently executed code regions. If the RDO finds that a candidate code region is hot, the DVPS testing and decision code starts to collect runtime information and decide how memory-bound the code region is. In addition, additional fine- grained DVFS settings would make the intratask DVFS design more effective. In the experiments conducted, RDO was forced to select an unnecessarily high voltage or frequency setting for many code regions in the benchmarks because the Pentium M processors lack intermediate steps between the six SpeedSteps.

Chromosomes are essential genomic information carriers. Chromosome classification constitutes an important part of routine clinical and cancer cytogenetics analysis. Cytogeneticists perform visual interpretation of banded chromosome images according to the diagrammatic models of various chromosome types known as the ideograms, which mimic artists' depiction of the chromosomes. In this paper, we present a subspace-based approach for automated prototyping and classification of chromosome images. We show that 1) prototype chromosome images can be quantitatively synthesized from a subspace to objectively represent the chromosome images of a given type or population, and 2) the transformation coefficients (or projected coordinate values of sample chromosomes) in the subspace can be utilized as the extracted feature measurements for classification purposes. We examine in particular the formation of three well-known subspaces, namely the ones derived from principal component analysis (PCA), Fisher's linear discriminant analysis, and the discrete cosine transform (DCT). These subspaces are implemented and evaluated for prototyping two-dimensional (2-D) images and for classification of both 2-D images and one-dimensional profiles of chromosomes. Experimental results show that previously unseen prototype chromosome images of high visual quality can be synthesized using the proposed subspace-based method, and that PCA and the DCT significantly outperform the well-known benchmark technique of weighted density distribution functions in classifying 2-D chromosome images. [ABSTRACT FROM AUTHOR]

The article discusses formal control techniques within the field of energy-efficient design. Formal control-theoretic techniques have proved useful in many dynamic control scenarios--from aerospace systems to manufacturing--because their formal underpinnings let designers analyze and bound worst case behavior. In microprocessor power control, such techniques let designers reason about individual control responses and enable them to predict response behavior when individual responses are composed into an overarching complex control response. The goal of DVFS is to scale the frequency to match varying performance demand, or workload changes. Because changing clock frequency will alter the execution speed, a perfect DVFS scheme will lead to a perfect match between the demand and domain execution capability with no performance degradation or energy waste because of a mismatch between the two. The article thus address the formal control-theoretic aspects of such mechanisms, pointing the community toward an era of mathematically provable, robust control algorithms.

Addresses the problem of analytically coordinating dissimilar voltage control actions to prevent collapse in a large power system. Steady-state voltage security evaluation; Optimal control direction; Optimal scheduling of control actions.

Multiplex fluorescence in situ hybridization (M-FISH) is a recently developed technology that enables. multi-color chromosome karyotyping for molecular cytogenetic analysis. Each M-FISH image set consists of a number of aligned images of the same chromosome specimen captured at different optical wavelength. This paper presents embedded M-FISH image coding (EMIC), where the foreground objects/chromosomes and the background objects/images are coded separately. We first apply critically sampled integer wavelet transforms to both the foreground and the background. We then use object-based bit-plane coding to compress each object and generate separate embedded bit streams that allow continuous lossy-to-lossless compression of the foreground and the background. For efficient arithmetic coding of bit planes, we propose a method of designing an optimal context model that specifically exploits the statistical characteristics of M-FISH images in the wavelet domain. Our experiments show that EMIC achieves nearly twice as much compression as Lempel-Ziv-Welch coding. EMIC also performs much better than JPEG-LS and JPEG-2000 for lossless coding. The lossy performance of EMIC is significantly better than that of coding each M-FISH image with JPEG-2000. [ABSTRACT FROM AUTHOR]

Presents a study that proposed a coding scheme for efficient compression of digital chromosome images. Review of the wavelet image coding; Description of the proposed coding scheme; Experimental results on two representative chromosome spread and karyotype image sets; Comparison between the proposed scheme and the technique used in commercial karyotyping systems; Conclusions.

Presents a study that analyzed the nonlinear effect of a radio frequency power amplifier in wireless communication systems (WCS). Expressions of the estimation of the out-of-band emission levels for each signal; Expressions of the power level and bandwidth of the signal; Details of the spectrum analysis conducted on the WCS; Conclusions.