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21.
Oil Spill Detection in Radarsat and Envisat SAR Images   总被引:8,自引:0,他引:8  
We present algorithms for automatic detection of oil spills in synthetic aperture radar (SAR) images. The algorithms consist of three main parts, namely: 1) detection of dark spots; 2) feature extraction from the dark spot candidates; and 3) classification of dark spots as oil spills or look-alikes. The algorithms have been trained on a large number of Radarsat and Envisat Advanced Synthetic Aperture Radar (ASAR) images. The performance of the algorithm is compared to manual and semiautomatic approaches in a benchmark study using 59 Radarsat and Envisat images. The algorithms can be considered to be a good alternative to manual inspection when large ocean areas are to be inspected  相似文献   
22.
In this paper, we present a formalism called feature grammar and its application to several problems of semantic analysis. Our extension concerns the structure of the feature value sets, which can be complex, and the definition of unification, which is dependent on this structure. Moreover, we introduce generation rules for feature symbols in order to determine well-formed symbols, which form the alphabet of a formal language for natural language analysis.  相似文献   
23.
Research from the individual-differences tradition pertinent to the optimal development of exceptional talent is reviewed, using the theory of work adjustment (TWA) to organize findings. The authors show how TWA concepts and psychometric methods, when used together, can facilitate positive development among talented youth by aligning learning opportunities with salient aspects of each student's individuality. Longitudinal research and more general theoretical models of (adult) academic and intellectual development support this approach. This analysis also uncovers common threads running through several positive psychological concepts (e.g., effectance motivation, flow, and peak experiences). The authors conclude by underscoring some important ideals from counseling psychology for fostering intellectual development and psychological well-being. These include conducting a multifaceted assessment, focusing on strength, helping people make choices, and providing a developmental context for bridging educational and industrial psychology to facilitate positive psychological growth throughout the life span. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
24.
The performance of mathematically talented 12- and 13-year-olds on various cognitive tasks was compared with that of average-ability youth, verbally talented youth, and college students. In Experiment 1, the hypothesis that mathematical talent includes enhanced problem-translation skills was supported: The mathematically talented students were better than other groups at writing equations expressing complex relationships. Although the mathematically talented group outperformed their average-ability peers, they were no better than the verbally talented group or the college students in rewriting and recalling the propositions in an algebra story problem. In Experiment 2, the hypothesis that mathematical talent includes enhanced ability to represent and manipulate information in short-term memory was strongly supported: the mathematically talented youth outperformed the other youth and, in most cases, performed as well as or better than the college students. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
25.
Our previous study showed that a single lipopolysaccharide (LPS) treatment to neonatal rats could induce a long-lasting neuroinflammatory response and dopaminergic system injury late in life. This is evidenced by a sustained activation of microglia and elevated interleukin-1β (IL-1β) levels, as well as reduced tyrosine hydroxylase (TH) expression in the substantia nigra (SN) of P70 rat brain. The object of the current study was to test whether co-administration of IL-1 receptor antagonist (IL-1ra) protects against LPS-induced neurological dysfunction later in life. LPS (1 mg/kg) with or without IL-1ra (0.1 mg/kg), or sterile saline was injected intracerebrally into postnatal day 5 (P5) Sprague-Dawley male rat pups. Motor behavioral tests were carried out from P7 to P70 with subsequent examination of brain injury. Our results showed that neonatal administration of IL-1ra significantly attenuated LPS-induced motor behavioral deficits, loss of TH immunoreactive neurons, as well as microglia activation in the SN of P70 rats. These data suggest that IL-1β may play a pivotal role in mediating a chronic neuroinflammation status by a single LPS exposure in early postnatal life, and blockading IL-1β might be a novel approach to protect the dopaminergic system against perinatal infection/inflammation exposure.  相似文献   
26.
In marine coatings, the ability to sustain constant release of antifouling agents (AFA(s)) over a long period of time has become increasingly important. One efficient approach to prevent that diffusion depletes the paint film's antifouling activity is to adsorb the AFA strongly to a specie with low translational mobility, such as a high molecular weight polymer. Therefore, the AFA, Medetomidine, was adsorbed onto a sulfonated polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene (SDPS) generating a Medetomidine–SDPS ion pair in an organic solvent. The interaction was investigated by 1H NMR in butanol (BuOH-d10) and on solid surfaces by the quartz crystal microbalance with dissipation monitoring technique (QCM-D) in two different solvents, seawater and o-xylene. From the NMR studies in butanol (BuOH-d10), a strong interaction between Medetomidine and SDPS was observed. From the QCM-D measurements, differences in affinity between Medetomidine and the SDPS was observed when changing from seawater to o-xylene. In seawater, the interaction was weak and displayed a large degree of reversibility compared to in o-xylene, where the interaction was strong and almost irreversible. Different swelling behaviour was also observed at the solid surfaces depending on the solvent used with o-xylene exhibiting the largest swelling of the polymer layer.  相似文献   
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28.
Resistively switching devices are considered promising for next‐generation nonvolatile random‐access memories. Today, such memories are fabricated by means of “top–down approaches” applying thin films sandwiched between nanoscaled electrodes. In contrast, this work presents a “bottom–up approach” disclosing for the first time the resistive switching (RS) of individual TiO2 nanoparticles (NPs). The NPs, which have sizes of 80 and 350 nm, respectively, are obtained by wet chemical synthesis and thermally treated under oxidizing or vacuum conditions for crystallization, respectively. These NPs are deposited on a Pt/Ir bottom electrode and individual NPs are electrically characterized by means of a nanomanipulator system in situ, in a scanning electron microscope. While amorphous NPs and calcined NPs reveal no switching hysteresis, a very interesting behavior is found for the vacuum‐annealed, crystalline TiO2–x NPs. These NPs reveal forming‐free RS behavior, dominantly complementary switching (CS) and, to a small degree, bipolar switching (BS) characteristics. In contrast, similarly vacuum‐annealed TiO2 thin films grown by atomic layer deposition show standard BS behavior under the same conditions. The interesting CS behavior of the TiO2–x NPs is attributed to the formation of a core–shell‐like structure by re‐oxidation of the reduced NPs as a unique feature.  相似文献   
29.
Parmigiano Reggiano (PR) is an Italian cooked, long-ripened cheese made with unheated cow's milk and natural whey starter. The microflora is involved in the manufacturing of this cheese, arising from the natural whey starter, the raw milk and the environment. Molecular studies have shown that mesophilic non-starter lactic acid bacteria (NSLAB) are the dominant microflora present during the ripening of PR. In this study, a characterisation of Lactobacillus rhamnosus isolated from a single PR manufacturing and ripening process is reported, using a combination of genotypic fingerprinting techniques (RAPD-PCR and REP-PCR). The intraspecies heterogeneity evidenced for 66 strains is correlated to their abilities to adapt to specific environmental and technological conditions. The detection of biotypes that correlate with specific moments in cheese ripening or differential development throughout this process suggests that these strains may have specific roles closely linked to their peculiar technological properties.  相似文献   
30.
Over the past three decades, the achievement of waves of American students with high intellectual potential has declined as a result of inequity in educational treatment. This inequity is the result of an extreme form of egalitarianism within American society and schools, which involves the pitting of equity against excellence rather than promoting both equity and excellence, anti-intellectualism, the "dumbing down" of the curriculum, equating aptitude and achievement testing with elitism, the attraction to fads by schools, and the insistence of schools to teach all students from the same curriculum at the same level. In this article we provide recommendations for creating positive change--recommendations that emphasize excellence for all, that call for responsiveness to individual differences, and that suggest basing educational policies on well-grounded research findings in psychology and education. Educational policies that fail to take into account the vast range of individual differences among students--as do many that are currently in us--are doomed to be ineffective. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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