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101.
102.
Rural communities in many parts of the tropics are dependent of forests for their livelihoods and for environmental services. Forest resources in the tropics have declined rapidly over the past century and therefore many developing countries in the tropics have reforestation programs. Although reforestation is a long-term process with long-term benefits, existing evaluations of the success of these programs tends to focus on short-term establishment success indicators. This paper presents a review of reforestation assessment that highlights the need to not only consider short-term establishment success, but also longer-term growth and maturation success, environmental success and socio-economic success. In addition, we argue that reforestation assessment should not be based on success indicators alone, but should incorporate the drivers of success, which encompasses an array of biophysical, socio-economic, institutional and project characteristics. This is needed in order to understand the reasons why reforestation projects succeed or fail and therefore to design more successful projects in future. The paper presents a conceptual model for reforestation success assessment that links key groups of success indicators and drivers. This conceptual model provides the basis for a more comprehensive evaluation of reforestation success and the basis for the development of predictive systems-based assessment models. These models will be needed to better guide reforestation project planning and policy design and therefore assist rural communities in tropical developing countries to alleviate poverty and achieve a better quality of life.  相似文献   
103.
104.
A survey of 312 public relations executives and educators examined how well practitioners and instructors perceive public relations students to be prepared for the practice, the content and value of public relations curricula and, the future of public relations education in the United States. Results are largely consistent with those from a slightly smaller 1998 survey, suggesting that the views of both groups are consistent over time and providing the first two data points in what it is hoped will develop into a longitudinal line of research addressing public relations education. Judgments regarding the desired characteristics among job applicants and essential curriculum content were extremely similar between the practitioner and educator groups with both wanting more emphasis on research, ethics and strategic planning as the field moves from a low-paid technical emphasis toward a much better paid strategic planning and research emphasis.  相似文献   
105.
This paper tests the cross-sectional robustness of the arbitrage pricing theory (APT) model using foreign exchange rate data to determine if the model is robust with respect to the various random samples and various factor analytic techniques. Factor scores are developed using various samples and factor analytic techniques to explain the returns for other samples and groupings. The APT model is found to be robust across samples and techniques.  相似文献   
106.
Ivy Lee's 1905 “Declaration of Principles” has been called the “starting point of modern public relations,” but what did it mean in the context of his time? Analysis of press discussion finds that, while press agentry was connected to the circus and theater, “corporate publicity” was linked to Theodore Roosevelt's call for the release of financial information in the public interest. The paper confirms that scholars do not have a clear understanding of public relations history and identifies areas for further research.  相似文献   
107.
ABSTRACT

In response to the growing importance of online education in social work education, this article describes the context of online teaching and learning in social work education. Online teaching and learning are further discussed in the context of historically Black colleges and universities (HBCUs). We emphasize the importance and need for trained faculty to teach in an online environment, particularly in HBCUs; offer an example of how the University of the District of Columbia, an HBCU, prepares its faculty to teach online; and conclude with specific strategies for online teaching and social work faculty. Finally, we provide recommendations for social work education.  相似文献   
108.
In this article we consider the problem of estimating a nonparametric conditional mean function with mixed discrete and continuous covariates by the nonparametric k-nearest-neighbor (k-nn) method. We derive the asymptotic normality result of the proposed estimator and use Monte Carlo simulations to demonstrate its finite sample performance. We also provide an illustrative empirical example of our method.  相似文献   
109.
As a result of efforts to end homelessness among U.S. veterans, more former service members are entering permanent supportive housing (PSH). While PSH has been successfully used to house homeless veterans, more research is needed about services beyond housing placement and retention. This study uses the Gelberg–Andersen behavioral model for vulnerable populations to determine associations between predisposing, enabling, and need characteristics and recent service use (i.e., services to satisfy basic needs, occupational development, financial, healthcare, mental health) among unaccompanied homeless veterans (N?=?126) entering PSH in Los Angeles. Among the significant findings, as indicated using univariable logistic regression models, were veterans who had incarceration histories were more likely to utilize basic needs services, compared to those without incarceration histories. Veterans who received an honorable discharge were more likely to utilize occupational development services, compared to veterans with other discharge statuses. Veterans who had a case manager were more likely to utilize mental health services than those without a case manager, while those who received social security were less likely to utilize mental health services compared to veterans who did not receive social security. Veterans who met criteria for a psychological disability and veterans who met criteria for probable PTSD were more likely to use basic needs services and mental health services than veterans who fell below these thresholds. Clinical implications for social workers including “equal access to services,” “enhancing economic stability,” “providing safe and affordable housing with trauma-informed services,” and “training service social workers to deliver well-informed linkages and services” are discussed.  相似文献   
110.
Given a configuration of pebbles on the vertices of a connected graph G, a pebbling move removes two pebbles from some vertex and places one pebble on an adjacent vertex. The pebbling number of a graph G is the smallest integer k such that for each vertex v and each configuration of k pebbles on G there is a sequence of pebbling moves that places at least one pebble on v. First, we improve on results of Hurlbert, who introduced a linear optimization technique for graph pebbling. In particular, we use a different set of weight functions, based on graphs more general than trees. We apply this new idea to some graphs from Hurlbert’s paper to give improved bounds on their pebbling numbers. Second, we investigate the structure of Class 0 graphs with few edges. We show that every n-vertex Class 0 graph has at least \(\frac{5}{3}n - \frac{11}{3}\) edges. This disproves a conjecture of Blasiak et al. For diameter 2 graphs, we strengthen this lower bound to \(2n - 5\), which is best possible. Further, we characterize the graphs where the bound holds with equality and extend the argument to obtain an identical bound for diameter 2 graphs with no cut-vertex.  相似文献   
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