On the basis of abundant fossil and subfossil bone remains, the ecological and faunal role of the narrow-skulled vole in zonal
rodent communities of northern Eurasia is analyzed over the period from the Late Pleistocene to the present time. Special
attention is given to the correlated dynamics of relative abundance of Microtus gregalis and other rodent species in the course of transition from one zonal type to another and to specific features of this correlation
in the southern, middle, and northern parts of the species range. It is shown that distinctive dimensional and morphotypic
features of the two currently existing subspecies, Microtus gregalis major Ogn. and M. g. gregalis Pall., are the product of concordant development of the species and environmental conditions in the past 3000–4000 years
(transition from the Holocene optimum to the present-day climate and state of the natural environment).
Published in Russian in Ekologiya, 2007, Vol. 38, No. 2, pp. 117–123.
The article was translated by the authors. 相似文献
Systems approaches to safety have received growing attention in modern accident investigation techniques (e.g., STAMP, Accimap) with the emphasis shifted to the organizational dynamics (or archetypes) that may lead to an erosion of defenses and a drift out of the safety margins. Although the literature contains many applications of archetypes and system dynamics to safety, this richness comes at a cost of learning. It has become very difficult for safety practitioners to integrate the diverse studies of system dynamics with their diverging models. To provide a practical tool of system dynamics in accident investigation, this article reviews earlier studies and integrates them as a classification of patterns of breakdown (or archetypes) of both human and organizational processes on the basis of two control models, that is, the Extended Control Model (ECOM) and the Viable System Model (VSM). In this article, archetypes are represented as variants of two generic templates of performance which exploit many elements of complexity theory and system control. Apart from providing a practical tool to safety practitioners to access the literature on archetypes, the generic templates of ECOM and VSM can be used in building simulators of individual and organizational processes for risk analysis. 相似文献
Heterogeneous photocatalysis has long been considered to be one of the most promising approaches to tackling the myriad environmental issues. However, there are still many challenges for designing efficient and cost-effective photocatalysts and photocatalytic degradation systems for application in practical environmental remediation. In this review, we first systematically introduced the fundamental principles on the photocatalytic pollutant degradation. Then, the important considerations in the design of photocatalytic degradation systems are carefully addressed, including charge carrier dynamics, catalytic selectivity, photocatalyst stability, pollutant adsorption and photodegradation kinetics. Especially, the underlying mechanisms are thoroughly reviewed, including investigation of oxygen reduction properties and identification of reactive oxygen species and key intermediates. This review in environmental photocatalysis may inspire exciting new directions and methods for designing, fabricating and evaluating photocatalytic degradation systems for better environmental remediation and possibly other relevant fields, such as photocatalytic disinfection, water oxidation, and selective organic transformations.
ABSTRACT: This work establishes an industrial water demand (IWD) model for a short term estimate, which considers water reuse technologies and discharge regulations, for the integrated circuit (IC) industry in northern Taiwan. Based on the optimization of an industrial water cost system, a computerized system dynamics model (SD model) is developed to generate individual firm IWD using data from year 2000. A market IWD is further constructed for 25 1C firms in the study area and is approximated by an inverse logistic curve. Analytical results demonstrate that price elasticity varies with water price in cases involving water reuse. 相似文献
This work illustrates the discrete vortex method (DVM) as a tool for simulating environmental fluid mechanics problems involving transport in the wake of a bluff body. The DVM was used to model both the long-time-averaged and instantaneous features of flow past a circular cylinder. Simulations were performed for Re = 140, 000. Verification testing was accomplished by refining time-step and vortex element circulation. The DVM was validated through comparison with experimental data from Cantwell and Coles. Verification testing demonstrated that, while global convergence is not possible for an unsteady flow simulation, it is possible to have convergence to physical results. This verification entails identifying a range of parameters in which a flow containing coherent structures and matching physical conditions is attainable. Validation tests demonstrated excellent agreement between experimental and simulated results for time-averaged velocity and shear stress profiles, as well as Strouhal number. 相似文献
