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11.
P. P. Popov 《Russian Journal of Ecology》2012,43(1):13-18
Reference populations identified within the continuous range of Norway (Picea abies) and Siberian (P. obovata) spuces significantly differ in biometric characters of seed scales, relative position in the same coordinate system (Root
1 and Root 2), phenotypic structure, and mutual taxonomic position (according to the squared Mahalanobis distance). Due to
the symmetrically equal positions of the populations relative to each other, they can be used as reference populations in
discriminant analysis at a two-, three- or five-class gradation of the test character. 相似文献
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We discuss a problem in the safety assessment of automatic control and protection systems. There is an increasing dependence on software for performing safety-critical functions, like the safety shut-down of dangerous plants. Software brings increased risk of design defects and thus systematic failures; redundancy with diversity between redundant channels is a possible defence. While diversity techniques can improve the dependability of software-based systems, they do not alleviate the difficulties of assessing whether such a system is safe enough for operation. We study this problem for a simple safety protection system consisting of two diverse channels performing the same function. The problem is evaluating its probability of failure in demand. Assuming failure independence between dangerous failures of the channels is unrealistic. One can instead use evidence from the observation of the whole system's behaviour under realistic test conditions. Standard inference procedures can then estimate system reliability, but they take no advantage of a system's fault-tolerant structure. We show how to extend these techniques to take account of fault tolerance by a conceptually straightforward application of Bayesian inference. Unfortunately, the method is computationally complex and requires the conceptually difficult step of specifying ‘prior’ distributions for the parameters of interest. This paper presents the correct inference procedure, exemplifies possible pitfalls in its application and clarifies some non-intuitive issues about reliability assessment for fault-tolerant software. 相似文献
14.
A. K. Zykova P. V. Pantyukhov N. N. Kolesnikova T. V. Monakhova A. A. Popov 《Journal of Polymers and the Environment》2018,26(4):1343-1354
This study examined biocomposites based on low-density polyethylene (LDPE) and lignocellulosic fillers [wood flour (WF) and oil flax straw (FS)] selecting four size fractions of each lignocellulosic material as fillers for the composites. The primary aim was to evaluate the influence of fraction size on the composites’ basic properties; to accomplish this, the composites’ mechanical properties, thermal oxidation, thermophysical characteristics, and water absorption capacity were examined. Then microphotographs of the samples were created and length-to-diameter (L/D) ratio of the fillers was calculated, finding that the L/D ratio increased with increasing particle size. The particle size influenced the oxidative degradation and water absorption processes in composites with oil flax but not in those with WF. Biodegradation tests performed on the recovered soil found that the loss of mass in composites based on LDPE and FS was higher than in the same composites with WF. Moreover, at the initial stage of composting, the biodegradation rate correlated with the size of filler particles (i.e., the larger the particles, the higher the degradation rate of the biocomposite). 相似文献
15.
Shtangeeva Irina Niemelä Matti Perämäki Paavo Popov Alexander Vesavaara Ilkka Suvela Ronja 《Environmental geochemistry and health》2022,44(2):537-550
Environmental Geochemistry and Health - Environmental pollution is becoming one of the most important global problems. Understanding the main factors affecting accumulation of toxic trace elements... 相似文献
16.
Sterol composition of three Baltic Sea mussels (Mytilus edulis, Cardium glaucum, Mya arenaria) was compared with the sterol composition of three biologically closely related mussels from the Black Sea (Mytilus galloprovincialis, Cardium edule, Mya arenaria). The qualitative sterol composition of the mussels studied was similar, but some quantitative differences were found. 相似文献
17.
Alexander M. Panichev Vladimir K. Popov Igor Yu. Chekryzhov Ivan V. Seryodkin Tatiana A. Stolyarova Sergey V. Zakusin Alexandr A. Sergievich Pavel P. Khoroshikh 《Environmental geochemistry and health》2016,38(6):1255-1270
Rocks eaten by wild animals on the Bolshoy Shanduyskiy kudur in the Sikhote-Alin region (Russian Federation) are zeolite–clay mineral complexes—products of weathering of zeolitized vitric tuffs of rhyolite composition, deposited in aqueous medium within the volcanic caldera of about 55 million years ago. By composition of rock-forming oxides, the tuffs refer to high-potassium calc-alkaline series. In trace elements of most favorite kudurites of the Bolshoy Shanduyskiy kudur, there are significantly increased contents of most of rare earth elements (2–5 times in comparison with surrounding rocks). The results of our analysis of geological and geochemical data on kudurs and kudurites in another part of the Sikhote-Alin, as well as on other regions of the world (particularly, in Africa and Indonesia), taking into account new data on the prevalence of rare earth elements in living matter and their medical and biological properties, enable us to consider the version of causal connection of the geophagy with rare earth elements. 相似文献
18.
Popov K Glazkova I Yachmenev V Nikolayev A 《Environmental pollution (Barking, Essex : 1987)》2008,153(1):22-28
Contamination of concrete at various nuclear power plants and spent nuclear fuel reprocessing facilities by radionuclides represents a significant problem for the world's nuclear power industries and nuclear waste management. The present publication summarizes the most recently published data on Electrokinetic Remediation (EK) of various concrete installations and advantageous effects of the combination of EK with different chelating agents. The specific aspects of decontamination of concrete and mortar surfaces are analyzed, such as: (a) effect of chelating agents (EDTA, citric acid), (b) effect of the zeta-potential (zeta) of concrete surface, (c) effects of sorption and complex formation equilibrium, and (d) specific advantages and problems of the electrokinetic decontamination process. The results of laboratory and in situ tests of chelating agent assisted EK removal of radionuclides are reported. It is demonstrated that the correct combination of EK with specific chelating agents can be effectively employed for decontamination of concrete surfaces. 相似文献
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Ehrich Dorothée Schmidt Niels M. Gauthier Gilles Alisauskas Ray Angerbjörn Anders Clark Karin Ecke Frauke Eide Nina E. Framstad Erik Frandsen Jay Franke Alastair Gilg Olivier Giroux Marie-Andrée Henttonen Heikki Hörnfeldt Birger Ims Rolf A. Kataev Gennadiy D. Kharitonov Sergey P. Killengreen Siw T. Krebs Charles J. Lanctot Richard B. Lecomte Nicolas Menyushina Irina E. Morris Douglas W. Morrisson Guy Oksanen Lauri Oksanen Tarja Olofsson Johan Pokrovsky Ivan G. Popov Igor Yu. Reid Donald Roth James D. Saalfeld Sarah T. Samelius Gustaf Sittler Benoit Sleptsov Sergey M. Smith Paul A. Sokolov Aleksandr A. Sokolova Natalya A. Soloviev Mikhail Y. Solovyeva Diana V. 《Ambio》2020,49(3):801-804
Ambio - In the original published article, some of the symbols in figure 1A were modified incorrectly during the typesetting and publication process. The correct version of the figure is provided... 相似文献
20.
An assessment of air quality in the vicinity of a selected school has been carried out by monitoring the concentrations of primary pollutants. The results has shown that during the school hours, the measured pollutants emitted from the cars next to the selected school, such as CO and NO(2), are always under the allowable limits for Kuwaiti air quality standards. On the other hand, the concentrations of non methane hydrocarbon pollutant (nm-HC), some of which are considered to be cancergenic, are found to be above the Kuwaiti standard most of the times. A traffic counter is used to record the number of cars in the main road next to the school in 15 min intervals for 10 days during the monitoring period for air quality. Statistical analysis is performed to develop a relation for prediction of the necessary reduction in traffic, based on CO concentrations, during morning and afternoon periods on working days. A computer dispersion model (CALINE4) is also used to assess the CO concentrations based on recorded flow of traffic and emission inventory with the prevailing meteorological conditions existed at the specified time. After the validation of model, different scenarios have been evaluated to provide an acceptable solution to resolve the traffic congestion problem near the schools in the early morning hours with substantial reduction in pollution levels. The optimal solution for CO concentration reduction by managing smooth traffic flow is to reduce the traffic intensity by half in early morning and afternoon rush hours. The results of the predicted CO concentration in the vicinity of the school for the model and the statistical analysis has shown reduction of 30% and 42% respectively, for approximately 50% decrease in the car use. On the other hand the predicted CO concentration for the model and the statistics reached 24% and 33% respectively when 50% of students opted for buses instead of using private cars. 相似文献