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101.
G. A. Butler 《Pattern recognition》1969,1(4):291-299
An efficient computer method which uses an extension of the familiar gravitational field to find clusters of multidimensional data is suggested. The manipulation of a single parameter, r, permits one's perspective of the data to range from the locally sensitive (where each datum is a cluster) to the globally sensitive (where the entire sample set is regarded as one cluster). The number of clusters and their locations are determined by a choice of r. The program finds clusters by converging on the nodes of the field in decreasing steps. Once located, the field is modified so that the known nodes are effectively precluded from further consideration. 相似文献
102.
Nigg Joel T.; Butler Karin M.; Huang-Pollock Cynthia L.; Henderson John M. 《Canadian Metallurgical Quarterly》2002,70(1):153
The theory that attention-deficit/hyperactivity disorder (ADHD) stems from a deficit in an executive behavioral inhibition process has been little studied in adults, where the validity of ADHD is in debate. This study examined, in high-functioning young adults with persistent ADHD and a control group, 2 leading measures of inhibitory control: the antisaccade task and the negative priming task. ADHD adults showed weakened ability to effortfully stop a reflexive or anticipated oculomotor response but had normal ability to automatically suppress irrelevant information. Results suggest that an inhibitory deficit in ADHD is confined to effortful inhibition of motor response, that antisaccade and negative priming tasks index distinct inhibition systems, and that persistence of ADHD symptoms into adulthood is associated with persistence of executive motor inhibition deficits. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
Examined the use of professional psychologists as providers of group psychotherapy/counseling and the doctoral training of psychologists as group treatment providers in 2 national surveys of 287 service agencies and of the American Psychological Association-accredited counseling and clinical doctoral psychology programs. Results indicate that group treatment is a widely established treatment modality and that psychologists function as group service providers at most of the clinical agencies where they are employed. The survey of doctoral programs indicated that the curricula of doctoral training programs do not reflect the importance of the group modality in clinical setting. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
Michael Leuschel Michael Butler 《International Journal on Software Tools for Technology Transfer (STTT)》2008,10(2):185-203
We present ProB, a validation toolset for the B method. ProB’s automated animation facilities allow users to gain confidence in their specifications. ProB also contains a model checker and a refinement checker, both of which can be used to detect various errors in B specifications.
We describe the underlying methodology of ProB, and present the important aspects of the implementation. We also present empirical evaluations as well as several case
studies, highlighting that ProB enables users to uncover errors that are not easily discovered by existing tools.
This research was carried out as part of the EU research project IST 511599 RODIN (Rigorous Open Development Environment for
Complex Systems). 相似文献
105.
M. E. Zvanut F. J. Feigl S. R. Butler S. L. Titcomb 《Journal of Electronic Materials》1985,14(3):343-366
We have investigated the effects of different annealing treatments on silicon dioxide films produced from the reaction of
dichlorosilane and nitrous oxide at 700° C. The electrical quality of these LPCVD films was evaluated by measuring oxide charge
and interface trap densities on metal oxide semiconductor (MOS) capacitors. These densities were measured before and after
avalanche injection of electron currents into the oxide films. The results of these studies were as follows. (1) The LPCVD
oxide films required a post deposition anneal at 1000° C to produce as-grown charge densities similar to those of a standarddry thermal oxide grown and annealed at 1000° C. (2) Post-injection charge densities of LPCVD films given a post deposition anneal
at 1000°C were an order of magnitude greater than those of the standard dry thermal oxide. (3) Different annealing treatments
produced a series of dominant electron trapping centers in the oxide bulk17 with capture cross sections ranging from 10−14 cm2 to 10−17 cm2. (4) The electron traps in the LPCVD oxides films were similar to those previously observed in standardwet thermal oxides grown and annealed above 1000° C. 相似文献
106.
Measurements are presented from eastern Canada of the polarisation-dependent ratio of microwave attenuation due to rainfall for vertical and horizontal linear polarisations, and of the frequency-dependent ratio of attenuation for a given polarisation. The exponent of the usual power law of frequency scaling of attenuation is 1.93±0.15 (SD) in the 11?17 GHz frequency range. 相似文献
107.
Teri Smith Susan Sharp Ann M. Manzardo Merlin G. Butler 《International journal of molecular sciences》2015,16(3):4416-4428
Advances made in genetic testing and tools applied to pharmacogenetics are increasingly being used to inform clinicians in fields such as oncology, hematology, diabetes (endocrinology), cardiology and expanding into psychiatry by examining the influences of genetics on drug efficacy and metabolism. We present a clinical case example of an adolescent male with anxiety, attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder who did not tolerate numerous medications and dosages over several years in attempts to manage his symptoms. Pharmacogenetics testing was performed and DNA results on this individual elucidated the potential pitfalls in medication use because of specific pharmacodynamic and pharmacokinetic differences specifically involving polymorphisms of genes in the cytochrome p450 enzyme system. Future studies and reports are needed to further illustrate and determine the type of individualized medicine approach required to treat individuals based on their specific gene patterns. Growing evidence supports this biological approach for standard of care in psychiatry. 相似文献
108.
Flooding can cause major disruptions in cities, and lead to significant impacts on people, the economy and on the environment. These impacts may be exacerbated by climate and socio-economic changes. Resilience thinking has become an important way for city planners and decision makers to manage flood risks.Despite different definitions of resilience, a consistent theme is that flood resilient cities are impacted less by extreme flood events. Therefore, flood risk professionals and planners need to understand flood impacts to build flood resilient cities. This paper presents a state-of-the-art literature review on flood impact assessment in urban areas, detailing their application, and their limitations. It describes both techniques for dealing with individual categories of impacts, as well as methodologies for integrating them. The paper will also identify future avenues for progress in improving the techniques. 相似文献
109.
Grey water recycling has been generally accepted and is about to move into practice in terms of sustainable development. Previous research has revealed the bacteria re-growth in grey water and reclaimed municipal water during storage. However, in most present grey water recycling practices, impacts of water quality changes during storage on the system's performance and design regulation have not been addressed. In this paper, performance of a constructed wetland based grey water recycling system was analysed by taking the constraint of residence time during storage into account using an object based household water cycle model. Two indicators, water saving efficiency (WSE) and residence time index (RTI), are employed to reflect the system's performance and residence time during storage respectively. Results show that WSE and RTI change with storage tank volumes oppositely. As both high WSE and RTI cannot be achieved simultaneously, it is concluded that in order to achieve the most cost-effective and safe solution, systems with both small grey and green tanks are needed, whilst accepting that only relatively modest water saving efficiency targets can be achieved. Higher efficiencies will only be practicable if water quality deterioration in the green water tank can be prevented by some means (e.g. disinfection). 相似文献
110.
Environmental implications of water efficient microcomponents in residential buildings 总被引:1,自引:0,他引:1
The Code for Sustainable Homes (CSH) in England sets out various water efficiency targets/levels, which form part of environmental performance criteria against which the sustainability of a building is measured. The code is performance based and requires reduction in per capita water consumption in households. The water efficiency related targets can be met using a range of water efficient microcomponents (WC, showers, kitchen taps, basin taps, dishwashers, washing machines, and baths). However, while the CSH aims at reducing the adverse environmental implications associated with the dwellings by promoting reduction in water consumption, little is known about the energy consumption and the environmental impacts (e. g. carbon emissions) resulting from water efficient end uses. This paper describes a methodology to evaluate the energy consumption and carbon emissions associated with the CSH's water efficiency levels. Key findings are that some 96% and 87% of energy use and carbon emissions, respectively associated with urban water provision are attributable to in-house consumption (principally related to hot water), and that achieving a defined water efficiency target does not automatically save energy or reduce carbon emissions. 相似文献