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11.
Tree health is a critical parameter for evaluating urban ecosystem health and sustainability. Traditionally, this parameter has been derived from field surveys. We used multispectral remote sensing data and GIS techniques to determine tree health at the University of California, Davis. The study area (363 ha) contained 8,962 trees of 215 species. Tree health conditions were mapped for each physiognomic type at two scales: pixel and whole tree. At the pixel scale, each tree pixel within the tree crown was classified as either healthy or unhealthy based on vegetation index values. At the whole tree scale, raster based statistical analysis was used to calculate tree health index which is the ratio of healthy pixels to entire tree pixels within the tree crown. The tree was classified as healthy if the index was greater than 70%. Accuracy was checked against a random sample of 1,186 trees. At the whole tree level, 86% of campus trees were classified as healthy with 88% mapping accuracy. At the pixel level, 86% of the campus tree cover was classified as healthy. This tree health evaluation approach allows managers to identify the location of unhealthy trees for further diagnosis and treatment. It can be used to track the spread of disease and monitor seasonal or annual changes in tree health. Also, it provides tree health information that is fundamental to modeling and analysis of the environmental, social, and economic services produced by urban forests.  相似文献   
12.
Sea levels are rising in many areas around the world, posing risks to coastal communities and infrastructures. Strategies for managing these flood risks present decision challenges that require a combination of geophysical, economic, and infrastructure models. Previous studies have broken important new ground on the considerable tensions between the costs of upgrading infrastructure and the damages that could result from extreme flood events. However, many risk-based adaptation strategies remain silent on certain potentially important uncertainties, as well as the tradeoffs between competing objectives. Here, we implement and improve on a classic decision-analytical model (Van Dantzig 1956) to: (i) capture tradeoffs across conflicting stakeholder objectives, (ii) demonstrate the consequences of structural uncertainties in the sea-level rise and storm surge models, and (iii) identify the parametric uncertainties that most strongly influence each objective using global sensitivity analysis. We find that the flood adaptation model produces potentially myopic solutions when formulated using traditional mean-centric decision theory. Moving from a single-objective problem formulation to one with multiobjective tradeoffs dramatically expands the decision space, and highlights the need for compromise solutions to address stakeholder preferences. We find deep structural uncertainties that have large effects on the model outcome, with the storm surge parameters accounting for the greatest impacts. Global sensitivity analysis effectively identifies important parameter interactions that local methods overlook, and that could have critical implications for flood adaptation strategies.  相似文献   
13.
This article extends the previous research of consecutive attacks strategy by assuming that an attacker observes the outcome of each attack imperfectly. With given probabilities it may wrongly identify a destroyed target as undestroyed, and wrongly identify an undestroyed target as destroyed. The outcome of each attack is determined by a contest success function that depends on the amount of resources allocated by the defender and the attacker to each attack. The article suggests a probabilistic model of the multiple attacks and analyzes how the target destruction probability and the attacker's relative resource expenditure are impacted by the two probabilities of incorrect observation, the attacker's and defender's resource ratio, the contest intensity, the number of attacks, and the resource distribution across attacks. We analyze how the attacker chooses the number of attacks, the attack stopping rule, and the optimal resource distribution across attacks to maximize its utility.  相似文献   
14.
15.
This article analyses evidence for each of the expected benefits of budget support in turn, and finds the biggest improvements in the pro‐poor nature of public expenditure and public financial management. More modest improvements are noted in the predictability of aid and the burden of transaction costs, while less is known about the real effects on domestic accountability. Underlying them all is an assessment that programmes are incapable of ‘buying’ reforms. Drawing on the analysis, seven areas are highlighted where budget support design can be strengthened vis‐à‐vis its original rationale.  相似文献   
16.
ABSTRACT

The purposes of this review article are to orient clinical social workers to cognitive-behavioral theory, intervention, and research on bipolar disorder (BD); identify pros and cons of applying cognitive-behavioral therapy (CBT) to social work clients with BD; and identify specific implications for clinical social work practice. Of the 545 articles that were obtained via the systematic review, 18 studies were identified as being potentially eligible for inclusion, and 9 of those studies ultimately satisfied the inclusion criteria. The results of each study were summarized via identifying statistically significant (p< .05) differences that existed between experimental cohorts who received CBT (plus pharmacotherapy) and control cohorts who received treatment as usual. Outcomes showed CBT cohorts as having significant improvement over their respective control groups. The review's implications for clinical social workers and the need for future research are discussed.  相似文献   
17.
Interdependence is a defining feature of close relationships, and alcohol use is one domain where one person’s motivations and behaviors can affect a partner’s well-being. Concern about partner drinking is a gauge that determines whether a partner’s alcohol use has the potential to be problematic to the relationship, and brief and efficient measurement of this construct can be used to serve clinicians, scientists, and practitioners. Across four studies (N = 1,807), we use item response theory analysis to present a 3-item brief screening tool assessing concern about partner drinking: Thinking about your Partner’s Drinking-3 (TPD-3). The TPD-3 revealed strong test–retest reliability and expected patterns of convergent, concurrent, and incremental validity with perceived partner drinking and alcohol-related consequences, behavioral responses to partner drinking, and relationship well-being. We present the TPD-3 as a useful screening tool and for measurement of concern about partner drinking when efficient assessment is desired.  相似文献   
18.
Over the past decade Canadian sociology has engaged in spirited debates on the sociology of sociological research, but it has barely begun to address its relation to Indigenous theorizing, scholarship, and politics. How does the discipline deal with the settler colonial history and current realities of Indigenous social lives, and where is the place in our field for Indigenous voices and perspectives? Drawing on Coulthard's politics of recognition and Tuck's damage‐centered research, we present here the first systematic empirical analysis of the place of Indigeneity in the Canadian Review of Sociology and the Canadian Journal of Sociology. We situate the presence of Indigeneity in Canadian sociology journals in the sociopolitical context of the time, and examine how imperialism, statism, and damage are oriented within the two journals. Most importantly, we challenge the silence in the discipline's intellectual frames and research programs with respect to Indigenous theorizing about the social world.  相似文献   
19.
Urban Ecosystems - Urbanization-induced habitat loss and alteration causes significant challenges for the survival of many species. Identifying how species respond to urbanization can yield...  相似文献   
20.
Following every U.S. decennial census since 1960, the U.S. Census Bureau has evaluated the completeness of coverage using two different methods. Demographic analysis (DA) compares the census counts to a set of independent population estimates to infer coverage differences by age, sex, and race. The survey-based approach (also called dual system estimation or DSE) provides coverage estimates based on matching data from a post-enumeration survey to census records. This paper reviews the fundamentals of the two methodological approaches and then initially examines the results of these two methods for the 2010 decennial census in terms of consistency and inconsistency for age groups. The authors find that the two methods produce relatively consistent results for all age groups, except for young children. Consequently, the paper focuses on the results for children. Results of the 1990, 2000, and 2010 decennial censuses are shown for the overall population in this age group and by demographic detail (age, race, and Hispanic origin). Among children, the DA and DSE results are most inconsistent for the population aged 0–4 and most consistent for ages 10–17. Results also show that DA and DSE are more consistent for Black than non-Black populations. The authors discuss possible explanations for the differences in the two methods for young children and conclude that the DSE approach may underestimate the net undercount of young children due to correlation bias.  相似文献   
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