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61.
62.
The mass, ionic and elemental size distributions of particulate matter (PM) measured indoors and outdoors in an apartment situated in a north–westward suburb of Prague are presented. The PM samples were collected by two Berner type low pressure impactors separating particles into 10 size fractions from 26 nm to 10 μm and were further analyzed by ion chromatography (IC) and proton induced X-ray emission (PIXE). Temperature, pressure and relative humidity were measured both indoors and outdoors parallel to PM sampling. The indoor and outdoor PM dynamics were recorded by two scanning mobility particle sizers (SMPS) and an aerodynamic particle sizer (APS). Finally, the ventilation rate was determined by a radon technique. Ion chromatography showed that the major inorganic components of the fine particle mode are sulfate, nitrate, and ammonium with very low indoor nitrate concentration. Crustal elements (Al, Si, Ca, Ti, Mn, and Fe) were associated with the coarse aerosol mode. The presence of people increased the mass concentration of coarse particles, whereas cooking, smoking, and burning of incense and candles contributed predominantly to the fine particle mode. Smoking and the burning of incense also increased the concentration of potassium, bromine and chlorine content in fine particles.  相似文献   
63.
After describing an innovative technology, the close-coupled gasification and cyclonic combustor, this article explores the policy issues that inhibit a superior sustainable solution fromflourishing. Discussion of technology includes defining biomass,explaining what biomass to energy means, what the advantages of biomass to energy are, and why gasification is a superior biomassto energy technology. Specifically the environmental benefits ofalternatives to landspreading of traditional manure management arediscussed, as well as the advantages of gasification versus traditional combustion techniques for high nitrogen fuels. The policy environment is explored, particularly regarding sustainability, manure management, and renewable energy. Artificial, non-sustainable barriers to renewable energy, and the impact of wide jurisdictional variability are discussed. North Carolina is identified as a unique jurisdiction to monitor because of its high volume of livestock manure, and laggard position in renewable energy advocacy. The authors contend that these two positions are unsustainable, and that pressures can beexpected to force the state to modify its renewable energy policies or risk losing market share in livestock production tomore pro-sustainable policy oriented states.  相似文献   
64.
Objective: In 2012 in the United States, pedestrian injuries accounted for 3.3% of all traffic injuries but, disproportionately, pedestrian fatalities accounted for roughly 14% of traffic-related deaths (NHTSA 2014 NHTSA. Traffic Safety Facts 2012 Pedestrians. Washington, DC: Author; 2014. DOT HS 811 888. [Google Scholar]). In many other countries, pedestrians make up more than 50% of those injured and killed in crashes. This research project examined driver response to crash-imminent situations involving pedestrians in a high-fidelity, full-motion driving simulator. This article presents a scenario development method and discusses experimental design and control issues in conducting pedestrian crash research in a simulation environment. Driving simulators offer a safe environment in which to test driver response and offer the advantage of having virtual pedestrian models that move realistically, unlike test track studies, which by nature must use pedestrian dummies on some moving track.

Methods: An analysis of pedestrian crash trajectories, speeds, roadside features, and pedestrian behavior was used to create 18 unique crash scenarios representative of the most frequent and most costly crash types. For the study reported here, we only considered scenarios where the car is traveling straight because these represent the majority of fatalities. We manipulated driver expectation of a pedestrian both by presenting intersection and mid-block crossing as well as by using features in the scene to direct the driver's visual attention toward or away from the crossing pedestrian. Three visual environments for the scenarios were used to provide a variety of roadside environments and speed: a 20–30 mph residential area, a 55 mph rural undivided highway, and a 40 mph urban area.

Results: Many variables of crash situations were considered in selecting and developing the scenarios, including vehicle and pedestrian movements; roadway and roadside features; environmental conditions; and characteristics of the pedestrian, driver, and vehicle. The driving simulator scenarios were subjected to iterative testing to adjust time to arrival triggers for the pedestrian actions. This article discusses the rationale behind creating the simulator scenarios and some of the procedural considerations for conducting this type of research.

Conclusions: Crash analyses can be used to construct test scenarios for driver behavior evaluations using driving simulators. By considering trajectories, roadway, and environmental conditions of real-world crashes, representative virtual scenarios can serve as safe test beds for advanced driver assistance systems. The results of such research can be used to inform pedestrian crash avoidance/mitigation systems by identifying driver error, driver response time, and driver response choice (i.e., steering vs. braking).  相似文献   
65.
Abstract

Objective: Drowsiness is a major cause of driver impairment leading to crashes and fatalities. Research has established the ability to detect drowsiness with various kinds of sensors. We studied drowsy driving in a high-fidelity driving simulator and evaluated the ability of an automotive production-ready driver monitoring system (DMS) to detect drowsy driving. Additionally, this feature was compared to and combined with signals from vehicle-based sensors.

Methods: The National Advanced Driving Simulator was used to expose drivers to long, monotonous drives. Twenty participants drove for about 4?h in the simulator between 10 p.m. and 2 a.m. They were allowed to use cruise control and traffic was sparse and semirandom, with both slower- and faster-moving vehicles. Observational ratings of drowsiness (ORDs) were used as the ground truth for drowsiness, and several dependent measures were calculated from vehicle and DMS signals. Drowsiness classification models were created that used only vehicle signals, only driver monitoring signals, and a combination of the 2 sources.

Results: The model that used DMS signals performed better than the one that used only vehicle signals; however, the combination of the two performed the best. The models were effective at discriminating low levels of drowsiness from moderate to severe drowsiness; however, they were not effective at telling the difference between moderate and severe levels. A binary model that lumped drowsiness into 2 classes had an area under the receiver operating characteristic (ROC) curve of 0.897.

Conclusions: Blinks and saccades have been shown to be predictive of microsleeps; however, it may be that detection of microsleeps and lane departures occurs too late. Therefore, it is encouraging that the model was able to distinguish mild from moderate drowsy driving. The use of automation may make vehicle-based signals useless for characterizing driver states, providing further motivation for a DMS. Future improvements in impairment detection systems may be expected through a combination of improved hardware, physiological measures from unobtrusive sensors and wearables, and the intelligent integration of environmental variables like time of day and time on task.  相似文献   
66.
An analysis of multiple species of Australian gall-inducing thrips with soldiers reveals a significant negative correlation between the size of gall produced and the reproductive division of labour. This correlation suggests that the evolution of smaller galls limited the available space and feeding sites for the offspring of female soldiers, and was a major factor that led to the evolution of an altruistic caste in the gall-inducers. We argue that high levels of inbreeding by singly mated foundresses and incestuous mating by her soldier offspring are key to this evolutionary relationship because they make the relatedness of a female soldier to her daughters and sisters approximately equal. Evidence that relatedness plays an important role is strengthened by the observation of outbred multiply mated foundresses and unbiased sex ratio of dispersers in Oncothrips waterhousei, and the inference that both gall volume and skew decreased along this lineage.  相似文献   
67.
68.
A case of epignathus, detected prenatally in a 20-week fetus, is described. The pathological features are discussed in relation to the biochemical and ultrasonographic findings.  相似文献   
69.
The greenhouse gases subject to emission reduction commitments under the UN Climate Convention include the fluorinated compounds sulphur hexafluoride (SF6), perfluorocarbons (PFCs) and hydrofluorocarbons (HFCs). The present study projects the emissions of these gases in Germany over the 1995–2010 period, with and without additional emission abatement efforts In the business-as-usual scenario, total emissions of the three fluorinated gases rise over the 1995–2010 period from 11,1 to 27.4 million tonnes CO2 equivalent. This rise is attributable to 72% to HFCs, used above all for refrigeration and stationary air-conditioning, for mobile air-conditioning, for blowing extruded polystyrene (XPS) foam and for one-component polyurethane (PU) foam. Soundproof glazing is the largest SF6 emission sector. Most PFC emissions come from semiconductor manufacturing and aluminium smelting. The reduction scenario does not achieve a stabilisation of fluorinated gas emissions either. The rate of growth is only slowed, with 11.1 million tonnes CO2 equivalent in 1995 growing to 14.9 million in 2010. The measures proposed to attenuate emissions growth are: mandatory equipment maintenance in refrigeration and stationary air-conditioning, refrigerant substitution of HFCs by CO2 in mobile air-conditioning, partial HFC substitution by CO2 in XPS foam blowing, 95% HFC substitution by flammable hydrocarbons in one-component PU foam. Complete SF6 phase-out is considered to be feasible in soundproof glazing. The PFC emissions of the semiconductor industry can be cut by 85% by new chamber cleaning technologies.  相似文献   
70.
Urban gardens are often heralded as places for building social, physical, and environmental health. Yet they are also sites of significant conflict based on competing political, economic, and ecological projects. These projects range from radical re-envisionings of liberatory urban spaces, reformist aesthetic and sanitary improvement programmes, to underwriting the production of the neo-liberal city. These projects are based on divergent visions of the garden ground itself, in particular, whether this is soil (the fertile and living source for growing food and social values) or dirt (an inert and even problematic substrate to be removed or built upon for development purposes). These are not fixed or mutually exclusive categories, but are unstable as soil/dirt moves in discursive and material ways over time and space. Contaminants such as lead in the soil contribute to this instability, reframing fertile soil as dangerous dirt. To understand this discursive and material movement of soil/dirt over time and space, a dynamic spatial politics framework is needed that encompasses three scalar concepts: location, duration, and interconnection. This paper applies this dynamic spatial politics framework to interpret the 30-year conflict over the fate of an urban garden in Sacramento, California, that began as a countercultural space and was eventually transformed into a manicured amenity for a gentrifying neighbourhood, and the role of soil lead contamination in this narrative.  相似文献   
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