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1.
Previous research has shown that sexual minority (i.e., nonheterosexual) individuals report increased problematic substance use involvement, compared with their sexual majority counterparts. We hypothesize that feelings of an unstable sense of self (i.e., identity disturbance) may potentially drive problematic substance use. The purpose of the current study is to examine identity disturbance among sexual minorities as a potential explanatory mechanism of increased sexual minority lifetime rates of substance dependence. Measures of identity disturbance and three indicators of sexual orientation from lifetime female (n = 16,629) and male (n = 13,553) alcohol/illicit drug users in Wave 2 of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) were examined. Findings generally showed that the increased prevalence of alcohol dependence, illicit drug dependence, and combined alcohol/illicit drug dependence as well as a younger age of alcohol use initiation among sexual minority women was associated with elevated levels of identity disturbance. The results were consistent with a mediational role for identity disturbance in explaining the association between sexual minority status and substance dependence and were generally replicated among male sexual minority respondents. The current research suggests that identity disturbance, a predictor of substance use, may contribute to heightened risk for substance dependence among certain subgroups of sexual minority individuals. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
2.
Image processing algorithms for 2D digital filtering, morphologic operations, motion estimation, and template matching involve massively parallel computations that can benefit from using reconfigurable systems with massive field programmable gate array (FPGA) hardware resources. In addition, each algorithm can be considered a special case of a generalized template matching (GTM) operation. Application performance on reconfigurable computer systems is often limited by the bandwidth to host or off chip memory. This paper describes the GTM operation and characterizes the data allocation and buffering strategies for the GTM operation on reconfigurable computers. Several mechanisms that support different levels of parallelism are proposed and summarized in the paper. Finally, the implementation of an infrared automatic target recognition application on two commercial FPGA boards is used to demonstrate the various design options with different data allocation and buffering mechanisms and the pruning of the design space based on the FPGA area and memory constraints.  相似文献   
3.
Boron/nitrogen substituted carbons were synthesized by co-pyrolysis of polyborazylene/coal tar pitch blends to yield a carbon with a boron and nitrogen content of 14 at% and 10 at%, respectively. The presence of heteroatoms in these carbons shifted the hydrogen evolution overpotential to −1.4 V vs Ag/AgCl in aqueous electrolytes, providing a large electrochemical potential window (∼2.4 V) as well as a specific capacitance of 0.6 F/m2. An asymmetric capacitor was fabricated using the as-prepared low surface area carbon as the negative electrode along with a redox active manganese dioxide as the positive electrode. The energy density of the capacitor exceeded 10 Wh/kg at a power density of 1 kW/kg and had a cycle life greater than 1000 cycles.  相似文献   
4.
Alcohol use may be viewed as an attempt (albeit maladaptive) to regulate negative emotional states. We examined associations between both negative and positive affects and alcohol use in outpatient women diagnosed with borderline personality disorder (BPD; n = 74), a prototype of emotional dysregulation, as well as a psychiatric control group of women with current depressive disorder (major depressive disorder/dysthymic disorder [MDD\DYS]; n = 50). Participants completed randomly prompted reports of mood and alcohol use up to six times a day over a 28-day period using electronic diaries. Mean levels of either positive or negative affects did not distinguish between drinkers and nondrinkers in either diagnostic group. However, levels of both negative and positive affects were positively associated with alcohol use at the momentary level in BPD drinkers. More robust findings were obtained with respect to within-person affective variability, which was related to alcohol use in multiple ways. BPD drinkers showed higher within-person variability for most negative affects than BPD nondrinkers; MDD\DYS drinkers in general showed less within-person variability than MDD\DYS nondrinkers for negative affects. Multilevel lagged analyses for BPD drinkers indicated that alcohol use was positively related to variability in all affects, concurrently, but fewer significant effects of affect variability on the next day's drinking or significant effects of alcohol use on the next day's affect variability were observed. Among MDD\DYS drinkers, we observed more significant associations between affect variability on next day's alcohol use and of alcohol use on next day's affect variability. We discuss theoretical and methodological issues relevant to these findings as well as implications for future research. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
5.
SRAM based FPGA are subjected to ion radiation in many operating environments. Following the current trend of shrinking device feature size & increasing die area, newer FPGA are more susceptible to radiation induced errors. Single event upsets (SEU), (also known as soft-errors) account for a considerable amount of radiation induced errors. SEU are difficult to detect & correct when they affect memory-elements present in the FPGA, which are used for the implementation of finite state machines (FSM). Conventional practice to improve FPGA design reliability in the presence of soft-errors is through configuration memory scrubbing, and through component redundancy. Configuration memory scrubbing, although suitable for combinatorial logic in an FPGA design, does not work for sequential blocks such as FSM. This is because the state-bits stored in flip-flops (FF) are variable, and change their value after each state transition. Component redundancy, which is also used to mitigate soft-errors, comes at the expense of significant area overhead, and increased power consumption compared to nonredundant designs. In this paper, we propose an alternate approach to implement the FSM using synchronous embedded memory blocks to enhance the runtime reliability without significant increase in power consumption. Experiments conducted on various benchmark FSM show that this approach has higher reliability, lower area overhead, and consumes less power compared to a component redundancy technique.  相似文献   
6.
7.
This paper describes the acceleration of an infrared automatic target recognition (IR ATR) application with a co-processor board that contains multiple field programmable gate array (FPGA) chips. Template and pixel level parallelism is exploited in an FPGA design for the bottleneck portion of the application. The implementation of this design achieved a speedup of 21 compared to running on the host processor. The paper then describes an FPGA resource manager (RM) developed to support concurrent applications sharing the FPGA board. With the RM, the system is dynamically reconfigurable. That is, while part of the co-processor board is busy computing, another part can be reconfigured for other purposes. The IR ATR application was ported to work with the RM and has been shown to adapt to the amount of reconfigurable hardware that is available at the time the application is executed.  相似文献   
8.
The budding yeast and model eukaryote Saccharomyces cerevisiae has been invaluable for purification and analysis of numerous evolutionarily conserved proteins and multisubunit complexes that cannot be readily reconstituted in Escherichia coli. For many studies, it is desirable to functionalize a particular protein or subunit of a complex with a ligand, fluorophore or other small molecule. Enzyme-catalysed site-specific modification of proteins bearing short peptide tags is a powerful strategy to overcome the limitations associated with traditional nonselective labelling chemistries. Towards this end, we developed a suite of template plasmids for C-terminal tagging with short peptide sequences that can be site-specifically functionalized with high efficiency and selectivity. We have also combined these sequences with the FLAG tag as a handle for purification or immunological detection of the modified protein. We demonstrate the utility of these plasmids by site-specifically labelling the 28-subunit core particle subcomplex of the 26S proteasome with the small molecule fluorophore Cy5. The full set of plasmids has been deposited in the non-profit plasmid repository Addgene ( http://www.addgene.org ).  相似文献   
9.
Clinical and population-based samples show high comorbidity between Substance Use Disorders (SUDs) and Axis II Personality Disorders (PDs). However, Axis II disorders are frequently comorbid with each other, and existing research has generally failed to distinguish the extent to which SUD/PD comorbidity is general or specific with respect to both specific types of PDs and specific types of SUDs. We sought to determine whether ostensibly specific comorbid substance dependence-Axis II diagnoses (e.g., alcohol use dependence and borderline personality disorder) are reflective of more pervasive or general personality pathology or whether the comorbidity is specific to individual PDs. Face-to-face interview data from Wave 1 and Wave 2 of the National Epidemiologic Survey on Alcohol and Related Conditions were analyzed. Participants included 34,653 adults living in households in the United States. We used hierarchical factor models to statistically partition general and specific personality disorder dimensions while simultaneously testing for specific PD-substance dependence relations. Results indicated that substance dependence-Axis II comorbidity is characterized by general (pervasive) pathology and by Cluster B PD pathology over and above the relationship to the general PD factor. Further, these relations between PD factors and substance dependence diagnoses appeared to largely account for the comorbidity among substance dependence diagnoses in the younger but not older participants. Our findings suggest that a failure to consider the general PD factor, which we interpret as reflecting interpersonal dysfunction, can lead to potential mischaracterizations of the nature of certain PD and SUD comorbidities. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
10.
The timing, molecular basis, and morphophysiological and behavioral consequences of the interaction between external environment and the internal genetic pool that shapes the nervous system over a lifetime remain important questions in basic neuroscientific research. Space station offers the opportunity to study this interaction over several life cycles in a variety of organisms. This short review considers past work in altered gravity, particularly on the vestibular system, as the basis for proposing future research on space station, and discusses the equipment necessary to achieve goals. It is stressed that, in keeping with the international investment being made in this research endeavor, both the questions asked and the technologies to be developed should be bold. Advantage must be taken of this unique research environment to expand the frontiers of neuroscience.  相似文献   
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