A 3-GHz 70-mb SRAM in 65-nm CMOS technology with integrated column-based dynamic power supply

Column-based dynamic power supply has been integrated into a high-frequency 70-Mb SRAM design that is fabricated on a high-performance 65-nm CMOS technology. The fully synchronized design achieves a 3-GHz operating frequency at 1.1-V power supply. The power supply at SRAM cell array is dynamically switched between two different voltage levels during READ and WRITE operations. Silicon measurement has proven this method to be effective in achieving both good cell READ and WRITE margins, while lowering the overall SRAM leakage power consumption.     

Dissociating Processes Supporting Causal Perception and Causal Inference in the Brain.

An understanding of relations between causes and effects is essential for making sense of the dynamic physical world. It has been argued that this understanding of causality depends on both perceptual and inferential components. To investigate whether causal perception and causal inference rely on common or on distinct processes, the authors tested 2 callosotomy (split-brain) patients and a group of neurologically intact participants. The authors show that the direct perception of causality and the ability to infer causality depend on different hemispheres of the divided brain. This finding implies that understanding causality is not a unitary process and that causal perception and causal inference can proceed independently. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Addressing Diversity Issues in Play Therapy.

Globalization is upon us, resulting in almost daily exposure to and interaction with highly diverse populations. To practice ethical play therapy, play therapists must become culturally competent. Play therapists are called on both to address cultural issues in therapy and to facilitate children's pride in, and preservation of, their culture. Despite this, the existing literature on cultural competence in psychotherapy has rarely been applied to play therapy practice. The author's goal is to do just that so as to provide play therapists with a model relevant to their work. Play therapists must first fully understand the concept of culture and its potential impact on their own lives, the lives of their clients, and the play therapy process. Second, play therapists need to develop adequate levels of culturally related awareness, skills, and knowledge. Last, they can ensure the work they do is more culturally sensitive and competent by following basic guidelines. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Large-scale mapping of boreal forest in SIBERIA using ERS tandem coherence and JERS backscatter data

Siberia's boreal forests represent an economically and ecologically precious resource, a significant part of which is not monitored on a regular basis. Synthetic aperture radars (SARs), with their sensitivity to forest biomass, offer mapping capabilities that could provide valuable up-to-date information, for example about fire damage or logging activity. The European Commission SIBERIA project had the aim of mapping an area of approximately 1 million km² in Siberia using SAR data from two satellite sources: the tandem mission of the European Remote Sensing Satellites ERS-1/2 and the Japanese Earth Resource Satellite JERS-1. Mosaics of ERS tandem interferometric coherence and JERS backscattering coefficient show the wealth of information contained in these data but they also show large differences in radar response between neighbouring images. To create one homogeneous forest map, adaptive methods which are able to account for brightness changes due to environmental effects were required. In this paper an adaptive empirical model to determine growing stock volume classes using the ERS tandem coherence and the JERS backscatter data is described. For growing stock volume classes up to 80 m³/ha, accuracies of over 80% are achieved for over a hundred ERS frames at a spatial resolution of 50 m.     

Response of seasonal vegetation development to climatic variations in eastern central Asia

Meteorological records show that central Asia has experienced one of the strongest warming signals in the world over the last 30 years. The objective of this study was to examine the seasonal vegetation response to the recent climatic variation on the Mongolian steppes, the third largest grassland in the world. The onset date of green-up for central Asia was estimated using time-series analysis of advanced very high resolution radiometer (AVHRR) normalized difference vegetation index (NDVI) biweekly composite data collected between January 1982 and December 1991. Monthly precipitation and mean temperature data (1982-1990) were acquired from 19 meteorological stations throughout the grasslands of the eastern Mongolian steppes in China. Our results showed that while the taiga forest north of the Mongolian steppes (>50°N) experienced an earlier onset of green-up during the study period, a later onset was observed at the eastern and northern edges of the Gobi Desert (40°N-50°N). Responses of different vegetation types to climatic variability appeared to vary with vegetation characteristics and spring soil moisture availability of specific sites. Plant stress caused by drought was the most significant contributor to later vegetation green-up as observed from satellite imagery over the desert steppe. Areas with greater seasonal soil moisture greened up earlier in the growing season. Our results suggested that water budget limitations determine the pattern of vegetation responses to atmospheric warming.     

Experience with a Hybrid Processor: K-Means Clustering

We discuss hardware/software co-processing on a hybrid processor for a compute- and data-intensive multispectral imaging algorithm, k-means clustering. The experiments are performed on two models of the Altera Excalibur board, the first using the soft IP core 32-bit NIOS 1.1 RISC processor, and the second with the hard IP core ARM processor. In our experiments, we compare performance of the sequential k-means algorithm with three different accelerated versions. We consider granularity and synchronization issues when mapping an algorithm to a hybrid processor. Our results show that speedup of 11.8X is achieved by migrating computation to the Excalibur ARM hardware/software as compared to software only on a Gigahertz Pentium III. Speedup on the Excalibur NIOS is limited by the communication cost of transferring data from external memory through the processor to the customized circuits. This limitation is overcome on the Excalibur ARM, in which dual-port memories, accessible to both the processor and configurable logic, have the biggest performance impact of all the techniques studied.     

Improved practical support for large-scale requirements prioritising

An efficient, accurate and practical process for prioritising requirements is of great importance in commercial software developments. This article improves an existing cost-value approach in which stakeholders compare all unique pairs of candidate requirements according to their value and their cost of implementation. Techniques for reducing the required number of comparisons are suggested, thus making the process more efficient. An initial approach for managing requirements interdependencies is proposed. A support tool for the improved process has been developed to make the process more practical in commercial developments. The improved process and its support tool have been applied and evaluated in an industrial project at Ericsson Radio Systems AB. The results indicate a pressing need for mature processes for prioritising requirements, and the work presented here is an important step in that direction.     

Modeling and Simulation of Porous Elastoviscoplastic Material

Many materials exhibit elasto–visco–plastic behavior when subjected to loadings with certain strain rate. Examples include natural materials such as metals, clays, and soils and manmade materials such as some biomimic materials. Some voids may exist or be introduced in these materials. The effects of the voids on the material response are important in predicting the strength, reliability, and service life of structural systems containing these materials. This paper presents the results of applying a statistical micromechanical approach to describe the macroscopic behavior of elasto–visco–plastic materials containing many randomly dispersed spherical voids. Most existing micromechanics based models are only applicable to monotonic proportional loadings. The limitation is removed by integrating the material model into the framework of continuum plasticity. With the discrete integration algorithm and local return mapping algorithm, the proposed computation method is applicable to any loading and unloading histories and is ready for implementing into finite element analysis.     

Trajectories of Alcohol and Drug Use and Dependence From Adolescence to Adulthood: The Effects of Familial Alcoholism and Personality.

This study describes trajectories of substance use and dependence from adolescence to adulthood. Identified consumption groups include heavy drinking/heavy drug use, moderate drinking/experimental drug use, and light drinking/rare drug use. Dependence groups include alcohol only, drug only, and comorbid groups. The heavy drinking/heavy drug use group was at risk for alcohol and drug dependence and persistent dependence and showed more familial alcoholism, negative emotionality, and low constraint. The moderate drinking/experimental drug use group was at risk for alcohol dependence but not comorbid or persistent dependence and showed less negative emotionality and higher constraint. Familial alcoholism raised risk for alcohol and drug use and dependence in part because children from alcoholic families were more impulsive and lower in agreeableness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mediating and Moderated Effects of Adolescent Behavioral Undercontrol and Parenting in the Prediction of Drug Use Disorders in Emerging Adulthood.

This study tested whether the effects of parental alcoholism on drug use disorders in emerging adulthood were mediated by behavioral undercontrol and parenting in adolescence and whether parenting buffered the relation between undercontrol and drug use disorders. Participants were 175 children of alcoholics and 190 matched control participants from an ongoing longitudinal study (L. Chassin, F. Rogosch, & M. Barrera, 1991). Results showed that undercontrol and parental discipline mediated 58% of the effect of parental alcoholism on drug use disorders. The relation between behavioral undercontrol and drug use disorders was further moderated by parental support. This effect was "protective but reactive" (S. S. Luthar, D. Cicchetti, & B. Becker, 2000); at high levels of behavioral undercontrol the protective effect of parental support was lost. Highly undercontrolled adolescents may have such a strong diathesis for drug use disorders that buffers may not have the same effect as in those with better control. (PsycINFO Database Record (c) 2010 APA, all rights reserved)