AbstractObjective: The current study investigated whether older drivers’ driving patterns during a customized on-road driving task were representative of their real-world driving patterns.Methods: Two hundred and eight participants (male: 68.80%; mean age?=?81.52 years, SD?=?3.37 years, range?=?76.00–96.00 years) completed a customized on-road driving task that commenced from their home and was conducted in their own vehicle. Participants’ real-world driving patterns for the preceding 4-month period were also collected via an in-car recording device (ICRD) that was installed in each participant’s vehicle.Results: During the 4-month period prior to completing the on-road driving task, participants’ median real-world driving trip distance was 2.66?km (interquartile range [IQR]?=?1.14–5.79?km) and their median on-road driving task trip distance was 4.41?km (IQR?=?2.83–6.35?km). Most participants’ on-road driving task trip distances were classified as representative of their real-world driving trip distances (95.2%, n?=?198).Conclusions: These findings suggest that most older drivers were able to devise a driving route that was representative of their real-world driving trip distance. Future research will examine whether additional aspects of the on-road driving task (e.g., average speed, proportion of trips in different speed zones) are representative of participants’ real-world driving patterns. 相似文献
AbstractObjectives: The objective of this study was to determine whether the amount of tension required for proper child restraint system (CRS) installation varies with lower anchor spacing and to determine whether nonexperts can produce adequate tension on wider-than-standard lower anchor configurations.Methods: CRSs were installed by certified child passenger safety technicians (CPSTs; n?=?6 subjects, n?=?72 installations) and nonexperts (n?=?30 subjects, n?=?120 installations) on a mock-up vehicle seat fixture with lower anchors set at 11 (standard), 15, 19, and 23 in. apart from one another. Each CPST installed a rear-facing (RF) infant base, RF convertible, and forward-facing (FF) convertible into each of the 4 spacing configurations in random order. The CPSTs were instructed to tighten the lower connector strap until the tension was exactly at the threshold between passing and failing the 1-in. test. Each nonexpert installed one CRS model into all 4 spacing conditions in random order. Nonexperts were instructed to install the CRS to the best of their ability. The tension produced on the lower connector strap was recorded via load cell in the lower anchor assembly of the vehicle seat. Resultant tension magnitudes were compared across spacing conditions using matched pair t-tests. The CPSTs’ mean 1-in. test threshold values were compared to tensions produced by nonexperts. Installations were visually evaluated for errors and qualitative usability feedback was collected via survey.Results: CPSTs installed the infant base with higher tensions in the 15-, 19-, and 23-in. configurations compared to the standard 11-in. configuration (P = .034, .032, and .003, respectively). The nonexperts installed the infant base with higher tension in the 15- and 23-in. configurations compared to the 11-in. configuration (P = .004 and .026, respectively). The RF convertible and FF convertible installations showed no significant differences in tension among any of the spacing configurations for either group. Only 19% of the nonexperts’ installations were tight enough to pass CPST thresholds, and the pass rate did not vary with respect to lower anchor spacing. In feedback surveys, the nonexpert group did not show a consistent preference for either standard or wider-than-standard lower anchor configurations.Conclusions: The amount of tension required to pass the 1-in. rule did not vary with lower anchor spacing configurations for the RF and FF convertible CRS, but the infant base required more tension in wider anchor configurations. Nonexperts tended to produce less than ideal tension in all configurations, although their tension magnitudes increased for the infant base in wider configurations. 相似文献
Different scenarios of recharge and discharge were assessed for sustainable management of groundwater in Quaternary aquifer east of Nile Delta. MODFLOW was utilized to investigate the effect of land use change and damming construction in the upstream of the Nile River on the current and short-term groundwater management strategies. The interpretive transient simulation was performed between 2004 and 2016 after steady-state calibration in 2004, and transient state from 2004 to 2013 with different irrigation recharges associated with land use change in this period. Sensitivity analysis was performed for hydraulic conductivities, recharge, and conductance parameters. The predictive transient simulation was run till 2023 under three scenarios of increasing pumping rates by 15, 30, and 50% for agriculture expansion and specified head reduction of Port Said Canal by 0.2, 0.4, and 0.6 m associated with the reduction of Nile water levels after Grand Ethiopian Residence Dam, GERD operation in 2017. Results from the in- and out-flow budgets showed that groundwater aquifer is stable at the current rate of pumping till 2023. Groundwater heads decreased by 0.2 and 0.42 m in the southern section, and a slight increase in the northern part was noticed for the first and second scenarios, respectively. When additional pumping stress is applied (50% increase), groundwater head dropped by 0.66 m, and the storage is no longer able to maintain the aquifer capacity after 2020 (worst-case scenario). 相似文献
The purpose of this paper is to study the impacts of the vagueness about the transfer of the harvest right on the use of a natural resource. We develop one-period non-cooperative game frameworks to examine whether the choice of the resource owner to be hazy about the transmission of the harvest contract is optimal. In the perfect information situation, we show that it is optimal for the resource owner to forbid the transfer of the harvest right instead of being hazy about it when the transfer fees are lesser than the collected net punishment fines of the monitoring costs even though the resource would be inefficiently used. In particular, we find in this case that the government’s announcement to forbid the transfer of the right should be public. We further show that there are subgame Nash equilibria in the perfect information context and a unique Nash equilibrium in the imperfect information setting. Specifically, we show that, when the transfer fees are greater or equal to the (net) punishment fines, there is a Nash equilibrium both in perfect and imperfect information situations, precisely when the owner chooses to allow the transfer of harvest title and the resource harvester transfers it. 相似文献
We introduce robust procedures for analyzing water quality data collected over time. One challenging task in analyzing such data is how to achieve robustness in presence of outliers while maintaining high estimation efficiency so that we can draw valid conclusions and provide useful advices in water management. The robust approach requires specification of a loss function such as the Huber, Tukey’s bisquare and the exponential loss function, and an associated tuning parameter determining the extent of robustness needed. High robustness is at the cost of efficiency loss in parameter loss. To this end, we propose a data-driven method which leads to more efficient parameter estimation. This data-dependent approach allows us to choose a regularization (tuning) parameter that depends on the proportion of “outliers” in the data so that estimation efficiency is maximized. We illustrate the proposed methods using a study on ammonium nitrogen concentrations from two sites in the Huaihe River in China, where the interest is in quantifying the trend in the most recent years while accounting for possible temporal correlations and “irregular” observations in earlier years. 相似文献
Species turnover patterns can be inconsistent due to differences in the dispersal ability of different growth forms. Here, species of trees, shrubs, herbs, and bryophytes in the Xiaoqinling National Nature Reserve in China were analyzed to determine patterns of species turnover along an elevation and spatial gradient. Variance partitioning was used to assess the relative contribution of topographic heterogeneity and dispersal limitation to species turnover. Our results suggest that the effect of dispersal limitation is more important than topographic heterogeneity on species turnover in temperate mountane ecosystems in the study area. Dispersal limitation has a greater effect on trees species turnover than on shrubs, herbs or bryophytes species turnover. 相似文献
The impact of succession stage on the share of clonal plants in the plant cover, seed rain and seedling pool has been studied in the years 2014 and 2015. The investigations were carried out in abandoned Molinion caeruleae meadows dominated by small-statured species (Patch I), tall growing large-tussock grasses (Patch II) and shrub-willows (Patch III). Although the clonal taxa dominated in the plant cover, seed rain and seedling pool, their share in subsequent study sites was quite different. The spectra of life-history traits relevant to clonality in the plant cover and seed rain were similar and did not vary significantly among subsequent locations, while they mostly differed as observed in the seedling pool. The various spectra observed in seedling pool in subsequent study sites might be due to fact that the seed germination and recruitment of offspring are strongly influenced by habitat conditions which varied remarkably in the successive Patches. 相似文献
The annual relative mass of storage organs cycle of Bufo gargarizans in southwestern China was studied from December 2005 to November 2006. We described how those organs changed in response to extreme temperatures. Energy reservation dropped to the lowest levels after dormancy for both sexes, and then increased for period of 4.25 month. However, the mass of these organs dropped again rapidly until August (liver) and September (fat bodies) due to the constraint from extreme high temperature occurred during the summer, and then non-significantly increased before hibernation. For ovaries, varied with a different profile to those of liver and fat bodies have a resting period of four months. In addition, the toads’ ovaries kept growing when the mass of liver and fat bodies declining accordingly during hibernation. Therefore, ovarian mass increased during the hibernation and non-hibernation period. 相似文献
Many factors such as human activities threat brown bears (Ursus arctos) in Southern Asia, and limit it to small populations in remote and rocky mountainous regions. Brown bears are generally studied in North America and Europe, but there is little information about its conditions and requirements for survival in Asia. During the recent years, brown bear populations in Iran have decreased sharply. Therefore, they are now officially listed as a threatened species in local scale. Therefore, we tried to recognize brown bear habitat relationships in northern Iran using species distribution model (SDM). Maxent method was applied using multiscale approach to predict suitable habitats and habitat relationships of the species. Our results revealed that the predictive ability of environment variables and species distribution maps varied across scales strongly. Also, our findings showed that identifying a proper scale is important issue to improve habitat modeling accuracy. Only 17% of the protected areas was found suitable for brown bear and divided to 5.1% poor, 8.8% suitable, and 3.1% high-quality habitat. Consequently, it is suggested that the protected area of northern Iran reconsiders with interventions aimed at maintaining suitable habitats of brown bear. 相似文献
Understanding how cities can transform organic waste into a valuable resource is critical to urban sustainability. The capture and recycling of phosphorus (P), and other essential nutrients, from human excreta is particularly important as an alternative organic fertilizer source for agriculture. However, the complex set of socio-environmental factors influencing urban human excreta management is not yet sufficiently integrated into sustainable P research. Here, we synthesize information about the pathways P can take through urban sanitation systems along with barriers and facilitators to P recycling across cities. We examine five case study cities by using a sanitation chains approach: Accra, Ghana; Buenos Aires, Argentina; Beijing, China; Baltimore, USA; and London, England. Our cross-city comparison shows that London and Baltimore recycle a larger percentage of P from human excreta back to agricultural lands than other cities, and that there is a large diversity in socio-environmental factors that affect the patterns of recycling observed across cities. Our research highlights conditions that may be “necessary but not sufficient” for P recycling, including access to capital resources. Path dependencies of large sanitation infrastructure investments in the Global North contrast with rapidly urbanizing cities in the Global South, which present opportunities for alternative sanitation development pathways. Understanding such city-specific social and environmental barriers to P recycling options could help address multiple interacting societal objectives related to sanitation and provide options for satisfying global agricultural nutrient demand.