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591.
Simon A. Mathias Paul E. Hardisty Mark R. Trudell Robert W. Zimmerman 《International Journal of Greenhouse Gas Control》2009,3(5):577-585
This paper presents a simple methodology for estimating pressure pressure buildup due to the injection of supercritical CO2into a saline formation, and the limiting pressure at which the formation starts to fracture. Pressure buildup is calculated using the approximate solution of Mathias et al. [Mathias, S.A., Hardisty, P.E., Trudell, M.R., Zimmerman, R.W., 2009. Approximate solutions for pressure buildup during CO2 injection in brine aquifers. Transp. Porous Media. doi:10.1007/s11242-008-9316-7], which accounts for two-phase Forchheimer flow (of supercritical CO2 and brine) in a compressible porous medium. Compressibility of the rock formation and both fluid phases are also accounted for. Injection pressure is assumed to be limited by the pressure required to fracture the rock formation. Fracture development is assumed to occur when pore pressures exceed the minimum principal stress, which in turn is related to the Poisson’s ratio of the rock formation. Detailed guidance is also offered concerning the estimation of viscosity, density and compressibility for the brine and CO2. Example calculations are presented in the context of data from the Plains CO2 Reduction (PCOR) Partnership. Such a methodology will be useful for screening analysis of potential CO2 injection sites to identify which are worthy of further investigation. 相似文献
592.
Charles C. Liu Author Vitae Simon G. Hosking Author Vitae Michael G. Lenné Author Vitae 《Journal of Safety Research》2009,40(4):239-245
Introduction
Driver drowsiness is a significant contributing factor to road crashes. One approach to tackling this issue is to develop technological countermeasures for detecting driver drowsiness, so that a driver can be warned before a crash occurs.Method
The goal of this review is to assess, given the current state of knowledge, whether vehicle measures can be used to reliably predict drowsiness in real time.Results
Several behavioral experiments have shown that drowsiness can have a serious impact on driving performance in controlled, experimental settings. However, most of those studies have investigated simple functions of performance (such as standard deviation of lane position) and results are often reported as averages across drivers, and across time.Conclusions
Further research is necessary to examine more complex functions, as well as individual differences between drivers.Impact on Industry
A successful countermeasure for predicting driver drowsiness will probably require the setting of multiple criteria, and the use of multiple measures. 相似文献593.
Xin Ye Ram M. Pendyala Simon P. Washington Karthik Konduri Jutaek Oh 《Safety Science》2009,47(3):443-452
Safety at roadway intersections is of significant interest to transportation professionals due to the large number of intersections in transportation networks, the complexity of traffic movements at these locations that leads to large numbers of conflicts, and the wide variety of geometric and operational features that define them. A variety of collision types including head-on, sideswipe, rear-end, and angle crashes occur at intersections. While intersection crash totals may not reveal a site deficiency, over exposure of a specific crash type may reveal otherwise undetected deficiencies. Thus, there is a need to be able to model the expected frequency of crashes by collision type at intersections to enable the detection of problems and the implementation of effective design strategies and countermeasures. Statistically, it is important to consider modeling collision type frequencies simultaneously to account for the possibility of common unobserved factors affecting crash frequencies across crash types. In this paper, a simultaneous equations model of crash frequencies by collision type is developed and presented using crash data for rural intersections in Georgia. The model estimation results support the notion of the presence of significant common unobserved factors across crash types, although the impact of these factors on parameter estimates is found to be rather modest. 相似文献
594.
Povinec PP Chudý M Sivo A Simon J Holý K Richtáriková M 《Journal of environmental radioactivity》2009,100(2):125-130
Radiocarbon variations in the atmospheric CO(2) with attenuating amplitudes and decreasing mean values with typical maxima in summer and minima in winter have been observed since 1967 in two localities of Slovakia, in Bratislava and Zlkovce, situated about 60 km NE from Bratislava, only 5 km from the Bohunice Nuclear Power Plant (NPP). The (14)C record in Bratislava has been influenced mainly by fossil CO(2) emissions, in contrast to the Zlkovce record which has been more variable, as it has clearly been affected by operation of the Bohunice NPP. However, during specific meteorological conditions with NE transport of air masses to Bratislava, the effect of the Bohunice NPP has been visible in Bratislava as well. Maximum (14)C concentrations (up to 120% above a natural background) were observed around A1 NPP which used CO(2) with admixture of air as a cooling agent. The (14)C concentrations around four pressurized light water reactors were up to 30% above the background. The Delta(14)C values in the heavily polluted atmosphere of Bratislava were up to 10% and at Zlkovce up to 5% lower than the European clean air represented by the Jungfraujoch Delta(14)C data. Later the Delta(14)C values were similar at both sites, and from 2003 they were close to the European clean air levels. The observed Delta(14)C behaviour in the atmosphere provides a unique evidence of decreased fossil fuel CO(2) emissions in the region, as well as the long-term effect of the Bohunice NPP on the Bratislava and Zlkovce stations. The estimated annual radiation doses to the local public due to digestion of radiocarbon contaminated food have been estimated to be around 3 microSv. 相似文献
595.
In the Segara Anakan lagoon, Java, 21 tree species and 5 understorey genera have been identified. Average tree density is
0.80 ± 0.99 Ind./m2 with 48.71% seedlings and an average basal area of 9.86 ± 10.54 cm2/m2. Tree density and diversity are
high in the eastern part of the lagoon, located near the city of Cilacap. There, the dominant tree species are Aegiceras corniculatum, Nypa fruticans and Rhizophora apiculata, of which the two latter are characteristic for mature forests. By contrast, understorey species and the pioneer species (Avicennia alba,
Aegiceras corniculatum and Sonneratia caseolaris) dominate the central lagoon where several rivers discharge. Compared to former studies, seedling density and tree diameter
in the central lagoon has declined considerably and tree species dominance has changed. The high sedimentation rates and deforestation
are likely to prevent the formation of a mature forest there. Tree communities are more equilibrated in the eastern lagoon
which points to a more stable and less disturbed mangrove forest. 相似文献
596.
597.
I. Offenthaler R. Bassan G. Jakobi N. Kräuchi K.-W. Schramm P. Simon?i? P. Weiss 《Environmental pollution (Barking, Essex : 1987)》2009,157(12):3280-3289
PCDD/F and PCB concentrations in remote mountainous spruce stands of the Central European Alps show strong geographic variation. Independent of the matrix (0.5 year old needles, humus or mineral soil), the highest pollutant levels were always found at the lateral zones of the mountain range. High levels coincided with strong precipitation, particularly along the northern margin of the study region. The most volatile PCB congener propagated farther into the colder, drier central Alps than the heavier species. Matrices with different accumulation history (needles and humus) repeatedly reflected different spatial immission patterns. Consistent with its much longer exposure, pollutant levels in humus exceeded those of needles by up to two orders of magnitude. Needle contamination varied with altitude but the vertical trends were highly variable between transsects and changed between years, too. 相似文献
598.
Moses Makonjio Okello Simon K. Ole Seno Rita Wairimu Nthiga 《Natural resources forum》2009,33(2):123-133
Two of the eight Millennium Development Goals (MDGs) adopted by the United Nations General Assembly in September 2000 are: eradication of extreme poverty and hunger; and ensuring environmental sustainability. The link between depressed livelihoods and unsustainable use of land and natural resources can be seen in Kenyan rangelands. Here, the local community is dependent on land and its resources for livelihoods, but the demand and competition is increasing, endangering both the resources they depend on and threatening environmental health. Amboseli is an Arid and Semi-Arid Land (ASAL) area that experiences ecological constraints, resource limitations, and low economic investment. Local communities in such landscapes are resource-dependent for their daily livelihoods, and have few socio-economic opportunities. Pastoralism, which is the main source of their wealth, continues to decline and exploitation by a few local elites and poor local leadership further depresses livelihoods. Other challenges to these poor rural landscapes are increasing human population which increases demands on natural resources and environment; persistent hunger; low universal primary education; poor gender equality and empowerment of women; environmental degradation; and lack of local and global partnership for development. This paper focuses on the two Millennium Development Goals mentioned above. Linkages, challenges and opportunities in enhancing rural livelihoods while promoting environmental sustainability in rural landscapes of the Amboseli Rural Landscape are discussed. 相似文献
599.
Evidence abounds attesting to changes in the global climate. In Ghana, climate change and climate variability have brought several exposure-sensitivities on different people and at different times. Due to the multiplicity of climate change and climate variability effects, adaptation strategies invariably could be influenced by several factors. This paper assesses the adoption of adaptation strategies in the rural northern savannah zone of Ghana as a result of climate change and variability. Using two villages each from Savelugu Nanton, West Mamprusi and Kassena Nankana East Districts, which are slightly different as case studies, the paper unearthed panoply of varied adaptation strategies in each of them including intensification of irrigation; integration of livestock production; changes in tillage practices; fertiliser application on farms; shift from agriculture to non-farm jobs; seasonal migration and purchase of drought insurance for maize. The results indicate that the relativity in adoption and utilisation of the different adaptive strategies are interlinked with geographical, social, economic, institutional and political factors and processes in the villages. The findings drum home the essentiality of location-specific planned adaptation strategies for climate change through a bottom-up approach, in order to ensure their effectiveness and sustainability. 相似文献
600.
Valéria R. F. da Silva Sylvia F. Mitraud Maria L. C. P. Ferraz Eduardo H. S. M. Lima Maria Thereza D. Melo Armando J. B. Santos Augusto César C. D. da Silva Jaqueline C. de Castilhos Jamyle A. F. Batista Gustave G. Lopez Frederico Tognin João Carlos Thomé Cecília Baptistotte Berenice M. Gomes da Silva José Henrique Becker Juçara Wanderline Fernanda de Vasconcellos Pegas Gonzalo Róstan Guy Guagni dei Marcovaldi Maria Ângela G. dei Marcovaldi 《Environment, Development and Sustainability》2016,18(6):1541-1558
In the 35 years since its inception, the Brazilian National Program for the Conservation of Marine Turtles (TAMAR) has had great success in protecting the five species of sea turtles that occur in Brazil. It has also contributed significantly to worldwide scientific data and knowledge about these species’ biology, such as life cycles and migration patterns. TAMAR’s conservation strategies have always relied on a variety of environmental education and social inclusion (EESI) activities highly adapted to the socio-environmental evolving contexts of its 25 locations distributed across nine states. Diversity and flexibility are critical to enable timely and effective local responses to existing or potential threats to sea turtles. The intuitive, locally adapted, decentralized, and independent way EESI activities have been carried out have generated positive results in the resolution of specific and evolving local problems through the course of the project. This article brings EESI under the same conceptual framework that underlies its conservation approach by adopting an adaptive threat management framework to organize and qualify its educational and social inclusion interventions according to the main categories of threat addressed by TAMAR. 相似文献