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51.
52.
We present a general methodology for developing environmental emergency decision support systems (EEDSS) based on an Artificial Neural Network (ANN). We highlight the method for developing the system using an illustrative example of an unexpected atmospheric accident with an ANN prototype system for a district in Shanghai. The network architecture of the ANN is introduced. Then the development process and key technologies are addressed. The procedures for matching the environmental emergency decision support characteristics are as follows: (1) digitization (coding) of case information and emergency measures, in which the information of cases are divided into the input attributes and decision-making information, and standardized and digitized through the Feature Evaluation (FE) method and the Intensity Hierarchical (IH) method, respectively; (2) construction of environmental emergency ANN, in which Gradient Descent with Momentum and Adaptive Learning Rate (GDMALR) method (traingdx function), a modified back-propagation algorithm, is employed to do training; and (3) translation (decoding) of decision-making information, in which output data of ANN is interpreted into practical contingency measures with Translation Based on Conventional Import Ratios (TBCIR) method. The training features, time, errors, accuracy, and input attribute weights of the prototype system are analyzed. The usage of the prototype system is demonstrated through a hypothetical case. This article encounters the challenge of ANN’s own lack of training samples. We discuss to the concept of integrating Case-Based Reasoning (CBR), Genetic Algorithm (GA), and ANN to overcome this difficulty and form a technology system for generating useful decision support information for environmental emergency response. 相似文献
53.
Self‐awareness represents an important aspect of leadership. However, past research on leader self‐awareness has focused on one component of self‐awareness, self versus others' ratings, leaving the second component, the ability to anticipate the views of others, largely neglected. We examined this second component of self‐awareness by focusing on women leaders who have been found to under‐predict how others rate them. In two studies, we measured how women leaders anticipate the views of their bosses in regard to their leadership. In Study 1, 194 leaders rated their leadership, were rated by their bosses, and then predicted how their bosses rated their leadership. While we found that women under‐predict their boss ratings compared with men, we did not find that boss gender or feedback played a role in this under‐prediction. In Study 2, 76 female leaders identified (via open‐ended questions) possible reasons and consequences of under‐prediction for women in organizations. Results from Study 2 reveal the following: (1) the reasons for women's under‐prediction include a lack of self‐confidence, differences in feedback needs, learned gender roles, and self‐sexism; and (2) the perceived consequences of under‐prediction are negative for both women and the organization. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
54.
Yu Miao Nicholas W. Johnson Kimberly Heck Sujin Guo Camilah D. Powell Thien Phan Phillip B. Gedalanga David T. Adamson Charles J. Newell Michael S. Wong Shaily Mahendra 《Frontiers of Environmental Science & Engineering》2018,12(5):2
Post-treatment impacts of a novel combined hydrogen peroxide (H2O2) oxidation and WOx/ZrO2 catalysis used for the removal of 1,4-dioxane and chlorinated volatile organic compound (CVOC) contaminants were investigated in soil and groundwater microbial community. This treatment train removed ~90% 1,4-dioxane regardless of initial concentrations of 1,4-dioxane and CVOCs. The Illumina Miseq platform and bioinformatics were used to study the changes to microbial community structure. This approach determined that dynamic shifts of microbiomes were associated with conditions specific to treatments as well as 1,4-dioxane and CVOCs mixtures. The biodiversity was observed to decrease only after oxidation under conditions that included high levels of 1,4-dioxane and CVOCs, but increased when 1,4-dioxane was present without CVOCs. WOx/ZrO2 catalysis reduced biodiversity across all conditions. Taxonomic classification demonstrated oxidative tolerance for members of the genera Massilia and Rhodococcus, while catalyst tolerance was observed for members of the genera Sphingomonas and Devosia. Linear discriminant analysis effect size was a useful statistical tool to highlight representative microbes, while the multidimensional analysis elucidated the separation of microbiomes under the low 1,4-dioxane-only condition from all other conditions containing CVOCs, as well as the differences of microbial population among original, post-oxidation, and post-catalysis states. The results of this study enhance our understanding of microbial community responses to a promising chemical treatment train, and the metagenomic analysis will help practitioners predict the microbial community status during the post-treatment period, which may have consequences for long-term management strategies that include additional biodegradation treatment or natural attenuation.
相似文献
55.
Phillip Cassey Golo Maurer Camille Duval John G. Ewen Mark E. Hauber 《Behavioral ecology and sociobiology》2010,64(10):1711-1720
Studies of avian eggshell coloration have been a long-standing research focus in behavioral evolutionary ecology. Museum collections
have provided a widely used resource because they allow efficient sampling across broad temporal, geographical, and taxonomic
ranges, even for species that are rare and for which sampling in the wild is ethically or practically unwarranted. We used
reflectance spectrophotometry across the avian visual spectrum to compare eggshell color of specimens of the song thrush (Turdus philomelos) in two museums (Natural History Museum, UK and Auckland Museum, New Zealand) with each other and with eggshells collected
fresh in New Zealand. These data enabled us to test the effects of source and storage in different museums, as well as time
since collection, across four metrics of eggshell coloration: blue-green and ultraviolet chroma, overall brightness, and the
spectral coefficient of variation. Variation within an egg, within a clutch, and among clutches, was similar between the two
museum datasets but different from those of fresh eggs. We found significant differences in all four metrics between the collections,
and that fresh eggshells reflected stronger in the blue-green wavelength than in museum eggs. This difference is most likely
due to different preservation techniques and storage histories. Furthermore, an effect of time since collection was only apparent
in the blue-green chroma and was higher in more recent museum eggshell samples. Our results support the use of historic museum
samples in intraspecific studies of shell coloration providing that efforts are made to compare specimens, which were collected
during similar periods. 相似文献
56.
Simple Modeling Tool for Reconstructing Source History Using High Resolution Contaminant Profiles From Low‐k Zones 下载免费PDF全文
David T. Adamson Steven W. Chapman Shahla K. Farhat Beth L. Parker Phillip C. deBlanc Charles J. Newell 《补救:环境净化治理成本、技术与工艺杂志》2015,25(3):31-51
An innovative but simple analytical modeling tool for reconstructing contaminant concentration versus time trends (i.e., “source history”) for a site using high‐resolution contaminant profiles from low permeability (low‐k) zones was developed and tested. Migration of contaminants into low‐k zones via diffusion (and possibly slow advection) produce concentration versus depth profiles that can be used to understand temporal concentration trends at the interface with overlying transmissive zones, including evidence of attenuation over time due to source decay. A simple transport‐based spreadsheet tool for generating source history estimates fit to the profiles was developed and applied to published soil concentration versus depth data from five distinct areas of four different sites contaminated with chlorinated ethenes. Using the root mean square error as an optimization metric, strong fits between measured and model‐predicted soil data were obtained in the majority of cases using site‐specific values for input parameters. In general, significant improvements could not be obtained by varying these parameters. As a result, the source history estimates generated by the tool were similar to those that had already been generated using more intensive analytical or numerical inverse modeling approaches. This included confirmation of constant source histories at locations where dense nonaqueous‐phase liquid was present (or suspected to be present), and declining source histories for locations where source isolation and/or attenuation had occurred. The advantage of the modeling tool described here is that it provides a simpler yet more dynamic method for understanding source behavior over time than existing approaches. ©2015 Wiley Periodicals, Inc. 相似文献
57.
58.
In birds, the position and extent of the region of binocular vision appears to be determined by feeding ecology. Of prime
importance is the degree to which vision is used for the precise control of bill position when pecking or lunging at prey.
In birds that do not require such precision (probe and filter-feeders), the bill falls outside the binocular field, which
extends above and behind the head, thus providing comprehensive visual coverage. Flamingos Phoenicopteridae are highly specialised
filter-feeders. They employ a unique technique that does not require accurate bill positioning in which the inverted head
is placed between the feet. Feeding flamingos often walk forwards with the head pointing “backwards”. Here we show that in
Lesser Flamingos Phoeniconaias minor visual fields are in fact the same as those of birds that feed by precision pecking and that feeding flamingos are blind
in the direction of their walking. We suggest that this is due to the requirement for accurate bill placement when flamingos
feed their chicks with “crop-milk”, and possibly when building their nest. We propose that chick-feeding may be the ultimate
determinant of visual field topography in birds, not feeding ecology. 相似文献
59.
Eggshell colour does not predict measures of maternal investment in eggs of <Emphasis Type="Italic">Turdus</Emphasis> thrushes 总被引:1,自引:0,他引:1
Cassey P Ewen JG Blackburn TM Hauber ME Vorobyev M Marshall NJ 《Die Naturwissenschaften》2008,95(8):713-721
The striking diversity of avian eggshell colour has long fascinated biologists. Recently, it has been proposed that the blue-green colour of some eggs may function as a post-mating sexually selected signal of female phenotypic quality to their mates to induce higher allocation of paternal care. It has been suggested that maternally deposited yolk carotenoids may be the specific aspect of reproductive quality that the female is signalling via eggshell colour. We use the known properties of the thrush visual system (Turdus sp.) to calculate photon capture for the four single cone photoreceptors, and the principal member of the double cone class for eggs in clutches of two introduced European thrush species (Turdus merula and Turdus philomelos) in New Zealand. We show that differences in the avian-perceived colours of individual eggs are not consistently correlated with different measures of maternal investment in the egg. Given the growing extent of the knowledge between maternal quality, parental investment and eggshell pigmentation across avian taxa, we encourage the use of avian perceptual modelling for testing alternative non-signalling explanations for the structural and physiological basis of these relationships. 相似文献
60.
Michael K. Theodorou Alison H. Kingston-Smith Ana L. Winters Michael R. F. Lee Frank R. Minchin Phillip Morris John MacRae 《Environmental Chemistry Letters》2006,4(3):121-126
Polyphenols in plants can protect proteins from degradation and improve the efficiency of conversion of plant protein to animal protein (meat and milk), but can this be achieved in a way that is environmentally sustainable, profitable to the livestock farmer and is consistent with aspirations for improved livestock nutrition, health, welfare and product quality? Given that grazed and conserved forage is the bedrock of sustainable ruminant production, this paper attempts to consider what challenges are ahead in terms of enhancing productive efficiency, reducing the polluting footprint of livestock agriculture and alleviating the endemic parasitism that occurs with grazing animals. 相似文献