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71.

Introduction

A converging pair of studies investigated the validity of a simulator for measuring driving performance/skill.

Study 1

A concurrent validity study compared novice driver performance during an on-road driving test with their performance on a comparable simulated driving test.

Results

Results showed a reasonable degree of concordance in terms of the distribution of driving errors on-road and errors on the simulator. Moreover, there was a significant relationship between the two when driver performance was rank ordered according to errors, further establishing the relative validity of the simulator. However, specific driving errors on the two tasks were not closely related suggesting that absolute validity could not be established and that overall performance is needed to establish the level of skill.

Study 2

A discriminant validity study compared driving performance on the simulator across three groups of drivers who differ in their level of experience - a group of true beginners who had no driving experience, a group of novice drivers who had completed driver education and had a learner's permit, and a group of fully licensed, experienced drivers.

Results

The findings showed significant differences among the groups in the expected direction -- the various measures of driving errors showed that beginners performed worse than novice drivers and that experienced drivers had the fewest errors. Collectively, the results of the concurrent and discriminant validity studies support the use of the simulator as a valid measure of driving performance for research purposes.

Impact on industry

These findings support the use of a driving simulator as a valid measure of driving performance for research purposes. Future research should continue to examine validity between on-road driving performance and performance on a driving simulator and the use of simulated driving tests in the evaluation of driver education/training programs.  相似文献   
72.
Environmental and Ecological Statistics - Dinophysis spp. can produce diarrhetic shellfish toxins (DST) including okadaic acid and dinophysistoxins, and some strains can also produce non-diarrheic...  相似文献   
73.
Hydrothermal carbonization (HTC) is a novel thermal conversion process that may be a viable means for managing solid waste streams while minimizing greenhouse gas production and producing residual material with intrinsic value. HTC is a wet, relatively low temperature (180-350 °C) thermal conversion process that has been shown to convert biomass to a carbonaceous residue referred to as hydrochar. Results from batch experiments indicate HTC of representative waste materials is feasible, and results in the majority of carbon (45-75% of the initially present carbon) remaining within the hydrochar. Gas production during the batch experiments suggests that longer reaction periods may be desirable to maximize the production of energy-favorable products. If using the hydrochar for applications in which the carbon will remain stored, results suggest that the gaseous products from HTC result in fewer g CO(2)-equivalent emissions than the gases associated with landfilling, composting, and incineration. When considering the use of hydrochar as a solid fuel, more energy can be derived from the hydrochar than from the gases resulting from waste degradation during landfilling and anaerobic digestion, and from incineration of food waste. Carbon emissions resulting from the use of the hydrochar as a fuel source are smaller than those associated with incineration, suggesting HTC may serve as an environmentally beneficial alternative to incineration. The type and extent of environmental benefits derived from HTC will be dependent on hydrochar use/the purpose for HTC (e.g., energy generation or carbon storage).  相似文献   
74.
The Mersey Basin Campaign was established in 1985 in the North West of England to address continuing problems of water quality and associated landward dereliction of the River Mersey and its tributaries. The Campaign's premise that water quality should be improved both for its own sake and as a stimulus to regeneration has proved to be well founded and has subsequently been extended to embrace community action to help nurture watercourse improvement and care. The Campaign can now be seen as a model for engaging co-ordinated environmental action through a partnership approach. This paper explores the nature of the Mersey Basin Campaign as an example of the new structures which are being developed in order to help deliver the new environmentalpolicy agenda. It is argued that the Campaign stands as a model for what will become an increasing need to develop focused environmental planning and management at the sub-regional and regional scales.  相似文献   
75.
Deep learning (DL) models are increasingly used to make accurate hindcasts of management-relevant variables, but they are less commonly used in forecasting applications. Data assimilation (DA) can be used for forecasts to leverage real-time observations, where the difference between model predictions and observations today is used to adjust the model to make better predictions tomorrow. In this use case, we developed a process-guided DL and DA approach to make 7-day probabilistic forecasts of daily maximum water temperature in the Delaware River Basin in support of water management decisions. Our modeling system produced forecasts of daily maximum water temperature with an average root mean squared error (RMSE) from 1.1 to 1.4°C for 1-day-ahead and 1.4 to 1.9°C for 7-day-ahead forecasts across all sites. The DA algorithm marginally improved forecast performance when compared with forecasts produced using the process-guided DL model alone (0%–14% lower RMSE with the DA algorithm). Across all sites and lead times, 65%–82% of observations were within 90% forecast confidence intervals, which allowed managers to anticipate probability of exceedances of ecologically relevant thresholds and aid in decisions about releasing reservoir water downstream. The flexibility of DL models shows promise for forecasting other important environmental variables and aid in decision-making.  相似文献   
76.
The Tampa Bay Ecosystem Services Demonstration Project (TBESDP) is part of the U.S. Environmental Protection Agency’s Ecosystem Services Research Program. The principal objectives of TBESDP are to (1) quantify the ecosystem services of the Tampa Bay watershed, (2) determine the value of ecosystem services to society, (3) predict the supply of ecosystem services under future scenarios of population growth and climate change, and (4) apply this knowledge through models and tools that will support the best informed environmental decisions possible. The scope and complexity of this project required intensive effort to establish which services can be quantified by applying existing models, data, and scientific literature and which services will require supporting research. Research priorities were assessed by: (1) developing and refining conceptual models of major ecosystems in the Tampa Bay region, (2) gathering input from stakeholders about the relative importance and values of various ecosystem services, (3) preparing and reviewing a bibliometric analysis of the volume of scientific literature relevant to the ecosystems and services of interest, and (4) evaluating an integrated analysis of importance, value, and availability of scientific information. This analysis led us to focus on two research priorities, seagrass-habitat functions as support for fishery production, and wetlands as regulators of water quality.  相似文献   
77.
Ethical treatment of wildlife and consideration of animal welfare have become important themes in conservation, but ethical perspectives on how best to protect wild animals and promote their welfare are diverse. There are advantages to the consequentialist harms ethical framework applied in managing wild herbivores for conservation purposes. To minimize harms while achieving conservation goals, we argue that overabundant wild herbivores should in many cases be managed through consumptive in situ killing. Advantages of this policy are that the negative welfare states imposed on animals last only a short time; remaining animals are not deprived of positive welfare states (e.g., linked to rearing offspring); poor welfare states of animals in overabundant populations are avoided (e.g., starvation); negative welfare impacts on heterospecifics through resource depletion (i.e., competition) are prevented; harvesting meat reduces the number of (agricultural) animals raised to supply meat; and minimal costs maximize funding for other wildlife management and conservation priorities. Alternative ethical approaches to our consequentialist framework include deontology (containing animal rights) and virtue ethics, some of which underpin compassionate conservation. These alternative ethical approaches emphasize the importance of avoiding intentional killing of animals but, if no population reduction occurs, are likely to impose considerable unintentional harms on overabundant wildlife and indirectly harm heterospecifics through ineffective population reduction. If nonlethal control is used, it is likely that overabundant animals would be deprived of positive welfare states and economic costs would be prohibitive. We encourage conservation stakeholders to consider animal-welfare consequentialism as an ethical approach to minimize harms to the animals under their care as well as other animals that policies may affect while at the same time pursuing conservation goals.  相似文献   
78.
The Ring-necked Pheasant ( Phasianus colchicus ) and the Chukar ( Alectoris chukar ) are the dominant avifauna in high-elevation shrubland (2070–3000 m) of Haleakala National Park, Maui, Hawaii. We studied the food habits, ecological niche, and effects of these alien game birds on the native biota in this Hawaiian ecosystem. Analyses of crop contents indicated that pheasant and Chukar consumed predominantly fruits of native, woody dicots (39% and 47% respectively) and leaves (29% and 24% respectively) and flower parts (12% and 17% respectively) of alien, herbaceous dicots. Both species generally selected food items according to their relative availability, although other factors influenced choice of certain items. Invertebrates were a minor component of the game-bird diet, suggesting that their impact on native invertebrate populations is minimal. Pheasant and Chukar occupy, at least partially, an ecological niche once held by now-extinct or rare birds, and they appear not to be significant competitors with the endangered Nene. The role of these alien birds in facilitating seed dispersal and germination of native plant species is beneficial in restoring degraded ecosystems.  相似文献   
79.
80.
ABSTRACT

Policy evaluation has grown significantly in the EU environmental sector since the 1990s. In identifying and exploring the putative drivers behind its rise – a desire to learn, a quest for greater accountability, and a wish to manipulate political opportunity structures – new ground is broken by examining how and why the existing literatures on these drivers have largely studied them in isolation. The complementarities and potential tensions between the three drivers are then addressed in order to advance existing research, drawing on emerging empirical examples in climate policy, a very dynamic area of evaluation activity in the EU. The conclusions suggest that future studies should explore the interactions between the three drivers to open up new and exciting research opportunities in order to comprehend contemporary environmental policy and politics in the EU.  相似文献   
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