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Susan J. Colarullo Manoutchehr Heidari Thomas Maddock III 《Journal of the American Water Resources Association》1984,20(5):747-760
A groundwater hydraulic management model is used to identify the optimal strategy for allocating limited fresh-water supplies and containing wastes in a hypothetical aquifer affected by brine contamination from surface disposal ponds. The present cost of pumping from a network of potential supply and interception wells is minimized over a five-year planning period, subject to a set of hydraulic, institutional, and legal constraints. Hydraulic constraints are formulated using linear systems theory to describe drawdown and velocity variables as linear functions of supply and interception well discharge decision variables. Successful validation of the optimal management strategy suggests that the model formulation can feasibly be applied to define management options for locally contaminated aquifer systems which are used to fulfill fresh-water demands. 相似文献
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In recent years, the unique stress experienced by those who do ‘people work’ has been acknowledged by the helping professions as a widespread problem and has been recognized by social scientists as a topic requiring systematic research. This paper begins by briefly reviewing research on the type of job stress experienced by workers in the helping professions. Then, a study of 142 police couples is reported, illustrating the effects of job stress on family life. In a survey study, police officers and their wives described family interactions. Officers who were experiencing stress, as measured by the Maslach Burnout Inventory, were more likely to display anger, spend time off away from the family, be uninvolved in family matters, and to have unsatisfactory marriages. An examination of the coping patterns used to deal with the stress of police work highlights differences between coping strategies used by husbands versus wives. 相似文献
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Emily Sherra Weeks Susan Walker Jake McC Overton Bruce Clarkson 《Environmental management》2013,51(5):1055-1066
Data needed for informed conservation prioritization are generally greater than the data available, and surrogates are often used. Although the need to anticipate threats is recognized, the effectiveness of surrogates for predicting habitat loss (or vulnerability) to land-use change is seldom tested. Here, we compared properties of two different vulnerability surrogates to validated vulnerability—validated prediction of habitat conversion based on a recent assessment of land-use change. We found that neither surrogate was a particularly effective predictor of vulnerability. Importantly, both surrogates performed poorly in places most imminently threatened with habitat conversion. We also show that the majority of areas protected over the last two decades have low vulnerability to the most active threatening process in this biome (habitat conversion). The contrary patterns of vulnerability and protection suggest that use of validated vulnerability would help to clarify protection needs, which might lead to the improvement of conservation decisions. Our study suggests the integration of validated vulnerability into conservation planning tools may be an important requirement for effective conservation planning in rapidly changing landscapes. We apply our results to discuss the practical considerations and potential value of incorporating validated vulnerability into conservation planning tools both generally and in the context of New Zealand’s indigenous grasslands. 相似文献
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Given the popularity of feeding white-tailed deer (Odocoileus virginianus) in Texas and the increasing amount of corn that is distributed, more information is needed on the impacts of this activity on non-target wildlife. Our objectives were to report visitation, intra- and interspecific contact, and contact rates of wildlife at artificial feeding sites in Texas. Our study was conducted at three sites in Kleberg and Nueces counties, Texas. We trapped animals from February to April and August to September, 2009 and marked animals with passive integrated transponder (PIT) tags. At each site and season, we placed one feeder system containing a PIT tag reader within 600 m of trap locations. Readers detected PIT tags from a distance of 25 cm. We determined a contact event to occur when two different PIT tags were detected by feeder systems within 5 s. We recorded 62,719 passes by raccoons (Procyon lotor), 103,512 passes by collared peccaries (Pecari tajacu), 2,923 passes by feral swine (Sus scrofa), 1,336 passes by fox squirrels (Sciurus niger), and no passes by opossums (Didelphis virginiana) at feeder systems. For site–season combinations in which contact events occurred, we found intraspecific contact rates (contacts per day) for raccoons, collared peccaries, and feral swine to be 0.81–124.77, 0.69–38.08, and 0.0–0.66, respectively. Throughout our study we distributed ~2,625 kg of whole kernel corn, which resulted in 6,351 contact events between marked wildlife (2.4 contacts per kg of corn). If 136 million kg of corn is distributed in Texas annually, we would expect >5.2 billion unnatural contact events between wildlife would result from this activity each year in Texas. Consequently, we do not believe that it is wise for natural resource managers to maintain artificial feeding sites for white-tailed deer or other wildlife due to pathogen transmission risks. 相似文献
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ABSTRACT“Community energy” (CE) is argued to be an opportunity to transition to low-carbon energy systems while creating additional benefits for local communities. CE is defined as energy initiatives that place a high degree of emphasis on participation of local community members through ownership and control, where through doing so, benefits are created for the community. The trend has seen considerable growth in many countries over the last decade. Occurring simultaneously is a trend for local communities (e.g. municipalities) to create their own Local Energy Plans (LEPs) – a planning process that articulates energy-related actions (i.e. expected outcomes). While CE and LEPs both address energy activities in a local context, any further connection between these trends remains unclear.This research develops a framework, based on CE and LEP literature, to assess LEPs for their relevance to CE. The research analyses 77 LEPs from across Canada for the ways in which they address the three components that define CE: community participation, community ownership, and community capacity. The main findings are that LEPs have emerged as a process that is both relevant to CE and capable of strategically addressing its components. Despite this, LEPs do not appear to reveal a radically different approach to the “closed and institutional” models of traditional community involvement practices. The investigation suggests that for CE advocates, LEPs may be considered to be an important avenue to pursue CE ambitions. LEPs could increase their relevance to CE by improving the processes and actions related to all three CE components. 相似文献
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Susan Caines Faisal Khan John Shirokoff 《Journal of Loss Prevention in the Process Industries》2013,26(6):1466-1483
Corrosion under insulation (CUI) is an important issue in marine environments. Pitting corrosion is a significant contributor to this issue. The ability to understand and model pitting behavior is integral to designing and maintaining assets in marine environments to decreased costs and increase safety and productivity. This paper reviews and analyses six categories of pitting knowledge to assess the current depth and breadth of understanding and to identify knowledge gaps in each category. The categories investigated are: identification of pitting, experimental methods, mechanism of pitting, modeling of pitting corrosion rates, remaining life assessment modeling, and risk-based inspections. This analysis finds that the depth of knowledge on pitting corrosion rate modeling and pitting mechanism is limited and requires further detailed study. The outcome of such study will strengthen pitting corrosion rate modeling, the accuracy of fitness-for-service assessments and risk-based inspection strategies. 相似文献
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