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71.
An Experiment in Participative Environmental Decision Making   总被引:2,自引:0,他引:2  
Summary The paper presents a method of participatory decision-making involving the authorities at local level, experts and the public. It studies how to solve the problems caused by the heterogeneity of the parties taking part in the decision-making process. The method builds on mutual learning and consideration among the participants following a systematic approach led by a moderator. The method was tested at a workshop simulating a real-life situation. The test case studied at the workshop was the problem of identifying the best site for a low and intermediate level radioactive waste repository among three alternatives. The learning phase was the Krško Nuclear Power Plant cooling problem. The results show that the participants were able to reach agreement on the prioritisation of the alternatives and to end up with suprisingly complex and fully reasonable decision models. We believe that this was achieved particularly due to the well defined procedure that guided the decision-making process, and the ability of all participants to see the influence of their views on the decision model.  相似文献   
72.
Concentration fields of different pollutants that spread outside two roadtunnels predicted with a CFD code will be presented. The solution domain represents the city area located between two tunnel outlets – tunnel Strahov and tunnel Mrazovka in Prague. The vicinity of both tunnels is a heavily built up area with tall buildings forming typical street canyons. The CFD modelling predicts the situation after the tunnel Mrazovka will be finished and traffic will increase considerably between both tunnels. Namely, an interest was given to the prediction of dispersion of emissions leaving both tunnel and the area touched by the traffic. For the CFD predictions, a method previously developed for moving vehicles was used. The method uses combination of Eulerian and Lagrangian approaches to moving objects and is capable of modeling different speeds and traffic rates of cars as well as traffic-induced turbulence. Influence of several meteorological parameters was studied, namely wind speed and direction and traffic parameters, like traffic rates and speed of cars. The method separates contributions from different sources to the total concentration field, namely from background, tunnel outlet and roadway. Results are presented in the form of horizontal and vertical concentration fields of NOx.  相似文献   
73.
The presented work deals with blends composed of polyvinyl alcohol (PVA) and biopolymers (protein hydrolysate, starch, lignin). PVA does not belong to biologically inert plastics but its degradation rate (particularly under anaerobic conditions) is low. A potential solution to the issue problem lies in preparation of blends with readily degradable substrates. We studied degradation of blow-molded films made of commercial PVA and mentioned biopolymers in an aqueous anaerobic environment employing inoculation with digested activated sludge from the municipal wastewater treatment plant. Films prepared in the first experimental series were to be used for comparing biodegradation of blends modified with native or plasticized starch; in this case effect of plasticization was not proved. The degree of PVA degradation after modification with native or plasticized starch increases in a striking and practically same manner already at a starch level as low as approximately 5 wt.%. Films of the second experimental series were prepared as additionally modified with protein hydrolysate and lignin. Only lignin-modified samples exhibited a somewhat lower degree of biodegradation but regarding the measure of lignin present in blend this circumstance is not essential. Level of biodegradation with all discussed films differed only slightly—within range of experimental error.  相似文献   
74.
An interdesciplinary attempt to formalize and numerically solve problems of the management of reservoir eutrophication is presented. A dynamic ecosystem model is treated by means of a generalized penalty optimization technique to calculate the combination of control actions that minimize cost under the condition that given water-quality indices are preserved.  相似文献   
75.
Magnetic and electromagnetic fields are now recognized by the 21st century medicine as real physical entities that promise the healing of various health problems, even when conventional medicine has failed. Today magnetotherapy provides a non-invasive, safe, and easy method to directly treat the site of injury, the source of pain and inflammation, and other types of diseases and pathologies. Millions of people worldwide have received help in treatment of musculoskeletal system, as well as pain relief. Pulsed electromagnetic fields are one important modality in magnetotherapy and recent technological innovations, such as Curatron pulsed electromagnetic field devices, offer excellent, state of the art computer controlled therapy system. In this article the development, state of the art and future of pulsed electromagnetic field therapy are discussed.  相似文献   
76.
Anthropogenic processes have increased the exposure of humans and wildlife to toxic methyl mercury (MeHg). Mercury emissions will increase by about 25% between 2005 and 2020, if the present trajectory is maintained. A global assessment of societal damages caused by the ingestion of methyl mercury, based merely on loss of IQ (Intelligence Quotient), suggests that the annual cost will be approximately US$3.7 billion (2005 dollars) in 2020. The corresponding cost of damages resulting from the inhalation of methyl mercury is estimated at US$2.9 million (2005 dollars). Under a higher degree of emission control such as in the case of the Extended Emission Control (EXEC) and the Maximum Feasible Technological Reduction (MFTR) scenarios, total emissions could decrease in the period 2005–2020 by about 50–60%. The corresponding annual benefits in 2020 are estimated to be about US$1.8–2.2 billion (2005 dollars). Large economic benefits can be achieved by reducing global mercury emissions.  相似文献   
77.
Whatman No. 1 filters impregnated with a 3% solution of oxalic acid in ethanol which are used for elimination of ammonia from the air stream before entering the absorber for collecting SO2, were tested for a possible application (a) in the spectrophotometric determination of ammonia with Nessler's reagent and (b) in the reflectometric determination of smoke. It was shown that impregnated filters were as suitable for the determination of ammonia as absorbing solution and as applicable for smoke measurement as untreated filters. Further, the advantage of using impregnated filters for sampling ammonia lies in avoiding the interference of organic vapours which may occur, if absorbing solution is used.  相似文献   
78.
The interest toward clinical application of magnetic and electromagnetic stimulation increases worldwide. Numerous publications discussed the possibility exogenous magnetic and electromagnetic fields to initiate effects on various biological processes, which are of critical importance for healing of different injuries and pathologies. Today, magnetic and electromagnetic fields are increasingly utilized for treatment of various musculoskeletal injuries and pathologies. For musculoskeletal injuries and post-surgical, post traumatic and chronic wounds, reduction of edema is a major therapeutic factor in the acceleration of pain and stress relief, and thus contribute to healing processes. Electromagnetic and magnetic fields appear to be unique in their safety during clinical use. The application of this new modality will be facilitated by searching for biophysical mechanisms of action as well as by establishing exact dosimetry of application. In that respect basic science research needs to be developed in parallel with clinical applications. Magnetotherapy provides a non-invasive, safe, and easy method to directly treat the site of injury, the source of pain and inflammation, and other types of injury. Unfortunately, there are many obstacles that magnetotherapy has to overcome—both from the mainstream medicine as well as from the manufacturers and distributors of magnetic devices. The physical principle of magnetism as well as the physiological bases for the use of magnetic field for tissue repair are subjects of this review.  相似文献   
79.
In response to Albrecht et al.’s (J Agric Environ Ethics 26(4):827–845, 2013) discussion on the ethics of assisted migration, we emphasize the issues of risk and scientific uncertainty as an inextricable part of a comprehensive ethical evaluation. Insisting on a separation of risk and ethical considerations, although arguably common in many policy contexts, is at best misguided and at worst damaging.  相似文献   
80.
A habitat transition model, based on the correlation between individual habitats and micro-elevation intervals, showed substantial changes in the future spatial distributions of coastal habitats. The research was performed within two protected areas in Slovenia: Se?ovlje Salina Nature Park and ?kocjan Inlet Nature Reserve. Shifts between habitats will occur, but a general decline of 42 % for all Natura 2000 habitats is projected by 2060, according to local or global (IPCC AR4) sea level rise predictions. Three different countermeasures for the long-term conservation of targeted habitat types were proposed. The most “natural” is displacement of coastal habitats using buffer zones (1) were available. Another solution is construction of artificial islets, made of locally dredged material (2); a feasible solution in both protected areas. Twenty-two islets and a dried salt pan zone at the desired elevations suitable for those habitats that have been projected to decease in area would offer an additional 10 ha in the Se?ovlje Salina. Twenty-one islets and two peninsulas at two different micro-altitudes would ensure the survival of 13 ha of three different habitats. In the area of Se?ovlje Salina, abandoned salt pans could be terrestrialized by using permanent, artificial sea barriers, in a manner close to poldering (3). By using this countermeasure, another 32 ha of targeted habitat could be preserved. It can be concluded that, for each coastal area, where wetland habitats will shrink, strategic plans involving any of the three solutions should be prepared well in advance. The specific examples provided might facilitate adaptive management of coastal wetlands in general.  相似文献   
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