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1.
This research investigates the utility of passive microwave remote sensing instruments to accurately determine snow water equivalent (SWE) over large spatial extents. Three existing Special Sensor Microwave Imager (SSM/I) snow water equivalent algorithms produced by Chang, Tait and Goodison were evaluated for their ability to determine snow water equivalent in a snowpack containing substantial depth hoar, large faceted snow crystals. The Kuparuk River Watershed (8140 km2) test site on the North Slope of Alaska was chosen for its snowpack containing a think depth hoar layer and long history of ground truth data. A new regional snow water equivalent algorithm was developed to determine if it could produce better results than the existing algorithms in an area known to contain significant depth hoar. The four algorithms were tested to see how well they could determine snow water equivalent: (1) on a per pixel basis, (2) across swath-averaged spatial bands of approximately 850 km2, and (3) on a watershed scale. The algorithms were evaluated to see if they captured the annual spatial distribution in snow water equivalent over the watershed. Results show that the algorithms developed by Chang and from this research are generally within 3 cm of the spatially averaged snow water equivalents over the entire watershed. The algorithms produced by Chang, Tait, and in this research were able to predict the basin-wide ground measured snow water equivalent value within a percent error range from −32.4% to 24.4% in the years with a typical snowpack. None of the algorithms produce accurate results on a pixel-by-pixel scale, with errors ranging from −26% to 308%. 相似文献
2.
Facilitatory priming effects due to similarity of orthographic form are obtained for high-N target words provided that they have low-frequency bodies and the body is shared between the prime and target (e.g., perd-HERD). Conversely, it is shown that low-N target words show priming regardless of the frequency of the body, provided that the prime and target do not share the same body (e.g., drice-DRIVE). If the body is shared, then priming occurs only for targets with low-frequency bodies. These results suggest that neighborhood density should be defined in terms of both individual letter units and subsyllabic units and that both types of density jointly determine priming. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
An attempt is made to isolate the assumptions that make a connectionist approach to visual word recognition distinctive. These include the commitment to distributed representations, the claim that there is no distinction between lexical and nonlexical systems in the naming task, and the claim that it is possible to map from orthography to meaning without using localized representations. It is argued that merely demonstrating that a network model can perform these tasks is not sufficient and that a detailed theory of how the network performs its tasks must accompany the simulation, because a simulation is not equivalent to an explanation. It is argued that further progress requires detailed modeling and experimental study of the elementary processes assumed to be involved in networks and that it is premature to dismiss alternative models of lexical access such as serial search models. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
Forster Jean L.; Jeffery Robert W.; Schmid Thomas L.; Kramer F. Matthew 《Canadian Metallurgical Quarterly》1988,7(6):515
Evaluated the feasibility and effectiveness of a program for weight gain prevention (WGP) in normal adults. 219 Ss were randomized to either WGP treatment or no treatment for 12 mo. The treatment group received monthly newsletters relating to weight management, participated in a financial incentive system, and were offered an optional 4-session education course in the 6th mo of the program. Results demonstrate high interest in WGP among Ss who were not objectively overweight. Participation, as measured by return of postcards sent with each newsletter, was approximately 75%. Results after 1 yr show a net weight loss of 1.8 lb in the group receiving the program compared with controls. 82% of participants maintained or lost weight, compared with 56% of controls. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
According to D. E. Broadbent's (1958) selective filter theory, people do not process unattended stimuli beyond the analysis of basic physical properties. This theory was later rejected on the basis of numerous findings that people identify irrelevant (and supposedly unattended) stimuli. A careful review of this evidence, however, reveals strong reasons to doubt that these irrelevant stimuli were in fact unattended. This review exposed a clear need for new experiments with tight control over the locus of attention. The authors present 5 such experiments using a priming paradigm. When steps were taken to ensure that irrelevant stimuli were not attended, these stimuli produced no priming effects. Hence, the authors found no evidence that unattended stimuli can be identified. The results support a modern version of Broadbent's selective theory, updated to reflect recent research advances. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Alireza Pourshahid Daniel Amyot Liam Peyton Sepideh Ghanavati Pengfei Chen Michael Weiss Alan J. Forster 《Electronic Commerce Research》2009,9(4):269-316
A number of recent initiatives in both academia and industry have sought to achieve improvements in e-businesses through the
utilization of Business Process Management (BPM) methodologies and tools. However there are still some inadequacies that need
to be addressed when it comes to achieving alignment between business goals and business processes. The User Requirements
Notation (URN), recently standardized by ITU-T, has some unique features and capabilities beyond what is available in other
notations that can help address alignment issues. In this paper, a URN-based framework and its supporting toolset are introduced
which provide business process monitoring and performance management capabilities integrated across the BPM lifecycle. The
framework extends the URN notation with Key Performance Indicators (KPIs) and other concepts to measure and align processes
and goals. An example process for controlling access to a healthcare data warehouse is used to illustrate and evaluate the
framework. Early results indicate the feasibility of the approach. 相似文献
7.
Frost Ram; Kugler Tamar; Deutsch Avital; Forster Kenneth I. 《Canadian Metallurgical Quarterly》2005,31(6):1293
Most models of visual word recognition in alphabetic orthographies assume that words are lexically organized according to orthographic similarity. Support for this is provided by form-priming experiments that demonstrate robust facilitation when primes and targets share similar sequences of letters. The authors examined form-orthographic priming effects in Hebrew, Arabic, and English. Hebrew and Arabic have an alphabetic writing system but a Semitic morphological structure. Hebrew morphemic units are composed of noncontiguous phonemic (and letter) sequences in a given word. Results demonstrate that form-priming effects in Hebrew or Arabic are unreliable, whereas morphological priming effects with minimal letter overlap are robust. Hebrew bilingual subjects, by contrast, showed robust form-priming effects with English material, suggesting that Semitic words are lexically organized by morphological rather than orthographic principles. The authors conclude that morphology can constrain lexical organization even in alphabetic orthographies and that visual processing of words is first determined by morphological characteristics. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
Electrical safety hazards in chlorine electrolytic cell rooms have been thoroughly discussed in previous papers. However, no attempt has ever been made to show the importance of maintaining maximum leakage resistance from the electrolytic cell line to ground. The majority of electrical shocks received by electrolytic cell room personnel are from the energized bus or chlorine cells to ground. As electrolytic cell lines are normally not grounded, the leakage resistance to ground has a definite effect on the severity of the majority of electrical shocks received by personnel. The leakage resistance problem is explained with the use of simple circuit diagrams, and solutions are suggested to eliminate electrical shocks to cell room personnel. 相似文献
9.
10.
Savvas Petrou Terence M. Sloan Muriel Mewissen Thorsten Forster Michal Piotrowski Bartosz Dobrzelecki Peter Ghazal Arthur Trew Jon Hill 《Concurrency and Computation》2011,23(17):2258-2268
The statistical language R and its Bioconductor package are favoured by many biostatisticians for processing microarray data. The amount of data produced by some analyses has reached the limits of many common bioinformatics computing infrastructures. High Performance Computing systems offer a solution to this issue. The Simple Parallel R Interface (SPRINT) is a package that provides biostatisticians with easy access to High Performance Computing systems and allows the addition of parallelized functions to R. Previous work has established that the SPRINT implementation of an R permutation testing function has close to optimal scaling on up to 512 processors on a supercomputer. Access to supercomputers, however, is not always possible, and so the work presented here compares the performance of the SPRINT implementation on a supercomputer with benchmarks on a range of platforms including cloud resources and a common desktop machine with multiprocessing capabilities. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献