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691.
Quantification and reduction of erroneous differences between images in remote sensing 总被引:1,自引:0,他引:1
The reliability of image data, along with the difficulty of accurately comparing images acquired at different times or from
different sensors, is a generic problem in remote sensing. Measurement repeatability errors occur frequently and can substantially
reduce the system’s ability to reliably quantify real spectral and spatial change in a target. This paper outlines methodologies
for quantifying and reducing erroneous differences between monochrome and multispectral or hyperspectral images. [Each of
these image types is acquired by an instrument that collects light photons across a variable range of the electromagnetic
spectrum (often referred to as an image band). The hyperspectral image is often referred to as a hyperspectral cube with XY
spatial dimensions and many Z bands (spectral demotions)]. In this paper, we specifically discuss the Pixel Block Transform
(PBT), the Spectral Averaging Transform (SAT), and the Wavelet Transform (WAVEL). We briefly address sensor fusion. Results
indicate that the PBT is a powerful cross-noise and repeatability error reducing tool, applicable to monochrome, multispectral,
and hyperspectral images. The SAT is as powerful as the PBT in reducing error but is suitable only for hyperspectral imagery.
WAVEL can reduce some of the finer scale noise, but it is not as powerful in reducing cross-noise as PBT or SAT and it requires
some trial and error for selecting the appropriate wavelet function. It is important that those involved in developing statistically
sound relationships between remotely sensed imagery and other data sources understand the problems and their solutions to
prevent wasting time or developing relationships that are statistically insignificant or unstable, or that lead to faulty
conclusions. 相似文献
692.
Erik Andersson Björn Nykvist Rebecka Malinga Fernando Jaramillo Regina Lindborg 《Ambio》2015,44(1):102-112
In this exploratory study we use existing in situ qualitative and quantitative data on biophysical and social indicators to compare two contrasting Swedish farming systems (low intensity and high intensity) with regard to ecosystem service supply and demand of a broad suite of services. We show that the value (demand) placed on a service is not necessarily connected to the quantity (supply) of the service, most clearly shown for the services recreation, biodiversity, esthetic experience, identity, and cultural heritage. To better capture this complexity we argue for the need to develop portfolios of indicators for different ecosystem services and to further investigate the different aspects of supply and demand. The study indicates that available data are often ill-suited to answer questions about local delivery of services. If ecosystem services are to be included in policy, planning, and management, census data need to be formatted and scaled appropriately. 相似文献
693.
694.
By combining digital humanities text-mining tools and a qualitative approach, we examine changing concepts in forestry journals in Sweden and the United States (US) in the early twentieth and early twenty-first centuries. Our first hypothesis is that foresters at the beginning of the twentieth century were more concerned with production and less concerned with ecology than foresters at the beginning of the twenty-first century. Our second hypothesis is that US foresters in the early twentieth century were less concerned with local site conditions than Swedish foresters. We find that early foresters in both countries had broader—and often ecologically focused—concerns than hypothesized. Ecological concerns in the forestry literature have increased, but in the Nordic countries, production concerns have increased as well. In both regions and both time periods, timber management is closely connected to concerns about governance and state power, but the forms that governance takes have changed. 相似文献
695.
Jian Yang Hui Sun Yu Qian Jie Yang 《Environmental science and pollution research international》2017,24(22):18160-18167
During ovary maturation of crabs, vitellogenin (Vg), a precursor molecule of vitellin (Vn) needed for embryogenesis, can be produced in large quantities in the hepatopancreas and then transported to the ovary by the hemolymph. In the present study, effects of Cd on Vg accumulation in the hepatopancreas and Vg transportation of the freshwater crab Sinopotamon henanense were investigated. We also studied the impacts of Cd on the mRNA expression of genes involved in energy metabolism, protein metabolism, and metallothionein (MT) and glutathione (GSH) synthesis. After Cd treatment, the Vg concentration and the Vg mRNA expression in the hepatopancreas were downregulated. Pearson’s correlation coefficient showed that the Vg level in the hepatopancreas correlated positively with those of the ovary and hemolymph (correlation coefficients 0.844 and 0.749, respectively), suggesting that the Vg transport from the hepatopancreas to the ovary can be impaired by Cd. The levels of carbohydrate and protein in the hepatopancreas of Cd-exposed crabs were decreased, and an inhibited protein metabolism was also observed. Energy production related isocitrate dehydrogenase and cytochrome C oxidase mRNA expressions, and MT and GSH synthesis increased after 10 days of Cd treatment and decreased after 20 days. Cd also caused a time-dependent upregulation of malondialdehyde. Our findings showed that Cd decreased Vg accumulation in the hepatopancreas due to partially excessive energy consumption and an activated defense system in the hepatopancreas, suggesting a possible regulatory mechanism in S. henanense which is the competitive advantage of energy reserves in metabolic Cd stress responses over the high-energy flux during vitellogenesis to ensure a continuous supply of metabolic energy. Moreover, the damage of Vg accumulation in the hepatopancreas caused by Cd could lead to an insufficient accumulation of Vn in the ovary and cause a retardation of oocyte development. 相似文献
696.
697.
Real time remote monitoring of air pollutants and their online transmission to the web using internet protocol 总被引:1,自引:0,他引:1
Anjaneyulu Y Jayakumar I Bindu VH Rao PV Sagareswar G Ramani KV Rao TH 《Environmental monitoring and assessment》2007,124(1-3):371-381
Recent advances in both information and sensor technologies have enabled the development of Real Time Remote Monitoring (RTRM)
capabilities for environmental management. An online and real time remote monitoring system for air pollution has been designed
and installed at a traffic police station at Punjagutta in Hyderabad, India. The system is optimized using electrochemical
sensors and a real time particulate matter analyzer. The system also monitors meteorological parameters such as temperature,
humidity, rainfall, barometric pressure, wind speed and wind direction. The system periodically monitors both pollution and
meteorological parameters at pre- programmed intervals of hr during peak periods and 1 hr during non peak periods of the day and continuously uploads to a predestinated web site (www.appcb.org/home.htm)
using File Transfer Protocol. The web site renders a quick, simple and graphical display of air pollution levels and meteorological
parameters and their significance to humans. The present paper highlights design considerations of a pollution monitoring
system, system hardware and software requirements and practical limitations and future directions for real time remote monitoring
of air pollution. 相似文献
698.
Gottfried Tappeiner Ulrike Tappeiner Janette Walde 《Environmental Modeling and Assessment》2007,12(4):253-256
The complexity of today’s research problems increasingly demands that scientists move beyond the confines of their own discipline.
In this special issue, the basics of a transdisciplinary framework are established and problems analyzed in a specific discipline
are successfully integrated in this transdisciplinary network. The intent has been to go beyond only statements about the
importance of enabling early stage researchers to work across disciplinary boundaries, and to show that important discoveries
are being made at the intersection of disciplines. Embedding various research projects in a more global framework can meet
the demands of an interdisciplinary or transdisciplinary approach (especially for early stage researchers) and contribute
significantly to sustainable research. 相似文献
699.
Charles S. Tapiero 《Environmental Modeling and Assessment》2005,9(4):201-206
Conclusion In this paper we have considered a specific environmental game emphasizing both control-prevention efforts and the propensity to pollute by a firm which adopts a given pollution abatement technology. A random payoff game was constructed and solved under a risk neutral assumption and quadratic utilities for both the firm and the environmental controller. The game thus defined, provides a wide range of interpretations and potential approaches for selecting a control-inspection policies to prevent environmental risks. There are of course many facets to this problem, which could be considered and have not been considered in sufficient depth. For example, more complex control mechanisms and liabilities, the effects of insurance and risk sharing, the application of cooperative efforts and subvention of pollution abatement investments (through tax incentives and their like), etc. have not been considered [5,7]. These are topics for further research. The basic presumption of this paper is that it is very difficult to fully enforce pollution prevention by firms, as a result, some controls are needed to ensure that firms be controlled so that appropriate efforts are carried. 相似文献
700.
Marcos R. Monteiro Daniela G. G. Moreira Marcelo A. Chinelatto Pedro A. P. Nascente Nelson G. Alcântara 《Journal of Polymers and the Environment》2007,15(3):195-199
The cell phone market is developing at a rapid speed. Today there are more than 1.6 billion consumers in the world, and the
lifetime of a cell phone is less than 2 years. As a consequence, there is an increase in the waste associated to this product,
and many alternatives to the disposal of the cell phones are being studied, such as recycling which shows to be the most important.
It is crucial to know what materials constitute the cell phone in order to carry out recycling and determine environmental
and economical issues. This work presents an evaluation of the cell phone components, characterizing the raw materials and
some properties of the recycled materials. 相似文献