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151.
152.
SUMMARY The emerging concept of industrial ecology (IE) has been applied in practice in few case studies on local/regional industrial recycling networks. Analogously to a natural ecosystem, the aim is to develop material cycles and energy cascades between local cooperative actors. An optimal resource basis of an industrial ecosystem is the sustainable use of local renewable natural resources. In this paper, we consider the region of North Karelia in Finland, with 19 municipalities, and hence somewhat expand the system boundaries of an industrial ecosystem case study. The current situation and two scenarios of municipal heating energy production are presented. The heating system consists of individual, district and electric heating. The heat production and related greenhouse gas emissions are considered. The current fuel use is based on imported oil and regional fuels (peat, wood wastes). Also, shares for co-production of heat and electricity (CHP) are shown. In scenario one, we assume the majority of the fuel basis in oil and absence of CHP. Scenario two illustrates nearly complete dependence on regional wood wastes and firewood with the current share of CHP. The North Karelia region provides the IE theory with a fruitful case study because the supply of waste fuels and local renewables is vast and waste utilisation technologies (CHP, fluidized bed burning) constitute a significant part of energy production. Implications of the applied scenario approach are discussed in the context of regional decision making and, in particular, for its implementation with the concepts of a regional environmental management system (EMS) and a regional industrial ecosystem management system (RIEMS). 相似文献
153.
André Borrmann Angelika Kneidl Gerta Köster Stefan Ruzika Markus Thiemann 《Safety Science》2012,50(8):1695-1703
In this contribution, a combination of a macroscopic and a microscopic model of pedestrian dynamics using a bidirectional coupling technique is presented which allows to obtain better predictions for evacuation times. While the macroscopic model is derived from dynamic network flow theory, the microscopic model is based on a cellular automaton. Output from each model is fed into the other, thus establishing a control cycle. As a result, the gap between the evacuation times computed by both models is narrowed down: The coupled model considers both optimized routing strategies as well as microscopic effects. Accordingly the typical underestimation of evacuation times by purely macroscopic approaches is reduced. At the same time the microscopic model is enhanced by a steering component which reflects the macroscopic knowledge and the impact of supervising personnel on the distribution of pedestrian flows. 相似文献
154.
The antennae of female European beewolves (Philanthus triangulum, Hymenoptera: Crabronidae) contain unique gland reservoirs that are inhabited by the symbiotic bacterium ‘Candidatus Streptomyces philanthi’. The reservoir content is secreted into the subterranean brood cells where it serves a dual function:
(1) It provides the larvae with spatial information about the orientation of cocoon spinning, and (2) it supplies the larva
with the symbiotic bacteria that are needed for the protection of the cocoon against pathogenic microorganisms. We analyzed
the hydrocarbon composition of the antennal gland secretion (AGS) by solid phase micro-extraction–gas chromatography–mass
spectrometry. We detected 28 substances, the majority of which were saturated and unsaturated hydrocarbons, with minor amounts
of some branched alkanes, two ketones, and three unknown substances. There was a strong dimorphism in the chemical composition
of the AGS among beewolf females. The two morphs had either (Z)-9-pentacosene (C25-type) or (Z)-9-heptacosene (C27-type) as the main component, and they differed significantly in the relative amounts of most of the other AGS substances.
The hydrocarbon composition of the AGS is very similar to that of the postpharyngeal gland of female beewolves, suggesting
that the hydrocarbons are universally used for different purposes and transported into the gland from the hemolymph. The putative
function of the hydrocarbons in the AGS is discussed. 相似文献
155.
Non-parametric statistical tests are commonly used in the behavioral sciences. Researchers need to be aware that non-parameteric
methods involving ranks can perform unreliably as a result of very small amounts of noise added in the storage and manipulation
of values by computers, causing spurious reduction in the number of ties. In order to avoid this problem, researchers should
round values to an appropriate number of decimal places prior to the ranking procedure to ensure that data points whose values
cannot be separated according to the precision of their measurement are recorded as having identical rank. We also recommend
exact rather than asymptotic evaluation of p values in non-parametric statistical tests. 相似文献
156.
Realistic meteorological fields are a prerequisite for the determination of pollutant concentrations and depositions by means
of a chemistry transport model. Different configurations of the 5th generation NCAR/Penn State University mesoscale meteorological
model MM5 were tested to determine the optimum set up for long term hindcasts that cover several months up to years. Four
dimensional data assimilation (FDDA) significantly enhances the spatio temporal representation of temperature, humidity and
wind. Best agreement with radiosonde observations could be achieved when temperature, humidity and wind were grid nudged every
6 h. The quality of the resulting meteorological fields showed no significant systematic temporal or spatial variation over
Europe in a model run of the year 2000. It was found that the hydrological cycle was not correctly reproduced by the model
when no nudging was applied. The relevant model run showed too high relative humidity and too high rainfall when compared
to observations. This led to considerably lower aerosol concentrations close to ground and a shift in the deposition patterns
of particle bound pollutants like the carcinogenic benzo(a)pyrene (B(a)P).
Guest Editor: Dr. S. T. Rao. 相似文献
157.
Jenni E Pettay Anna Rotkirch Alexandre Courtiol Markus Jokela Virpi Lummaa 《Behavioral ecology and sociobiology》2014,68(1):135-143
The fitness benefits of multiple mating determine the strength of sexual selection in each sex. This is traditionally quantified by the number of offspring born to once versus multiply mated individuals. In species with (bi)parental care, however, this measure may overestimate the benefits of multiple mating since having several mates can increase offspring number but decrease offspring quality. We analyzed short- and long-term fitness consequences of multiple marriages for both sexes in humans in preindustrial Finnish populations, where monogamy was socially enforced and remarriage was possible only after widowhood. Remarriage increased the lifetime number of offspring sired by men by lengthening their reproductive span but was unrelated to the lifetime number of births for women. However, neither men's nor women's long-term fitness, measured as their number of grandchildren, was significantly increased or decreased by remarriage. These associations were not modified by individual wealth. Our results suggest that despite increasing the number of offspring sired by men, the long-term fitness benefits of serial monogamy may be negligible for both sexes when parental investment is crucial for offspring success and continues to adulthood. They also demonstrate the importance of incorporating long-term fitness measures when quantifying the benefits of mating and reproductive strategies. 相似文献
158.
Scents form the basis for the fragrance industry and various research activities have been developed in different scientific
disciplines all being linked by a common interest in odors and odor perception. In this paper, four different topics have
been selected for a short discussion. Following a short overview on the history of perfumery, the first topic (Natural scents)
is providing some insight into the investigation of natural scents and how this work has strongly stimulated fragrance creation
as well as the quest to find new odoriferous substances for the perfumer’s palette. The second subject (Fragrance chemistry)
gives a historical overview over the chemistry of fragrances and briefly describes the rational behind the synthesis and composition
of new scents. Body odors and their biochemical formation concern the third topic (Body odor biochemistry) which describes
our current understanding of this scientifically interesting field and how knowledge may find use to improve future deodorant
products. The fourth subject (Olfactory mechanisms) deals with the biochemistry in the human nose when odorants are activating
olfactory receptors and enzymes appear to rapidly metabolize the inhaled odorous stimuli. This review does not attempt to
be comprehensive, but it describes selected successes in the fragrance industry and the motivation behind conducting various
types of research. Ultimately, the activities are aiming to bring new ingredients onto the market and improve the quality
of scented products but also to advance our understanding of the power of communication through fragrance. 相似文献
159.
The EU Emissions Trading System (ETS) demonstrated the ability to design and launch a large-scale trading system in a short period of time. The path from initial reticence about emissions trading to implementation of the world's largest program is an important history. Three issues play a large role in the evaluation of the program to date and its on-going development: allocation plans, cost uncertainty, and leakage of emissions to abroad. Decisions in Phase I and II (2005-2012) were responsive to questions of political feasibility and implementation, but some of these decisions including allocation in particular will be substantially revised in Phase III (2013-2020). 相似文献
160.