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661.
Understanding contemporary urban landscapes requires multiple sets of spatially and temporally compatible data that can integrate historical land use patterns and disturbances to land cover. This paper presents three principal methods: (1) core analysis; (2) historic mapping; and (3) gradient analysis, to link spatial and temporal data for urban ecosystems and applies their use in the Baltimore-Chesapeake region. Paleoecological evidence derived from the geochronology of sediment cores provides data on long-term as well as recent changes in vegetative land cover. This information, combined with contemporary vegetation maps, provides a baseline for conducting trend analyses to evaluate urbanization of the landscape. A 200-year historical land use database created from historical maps, census data, and remotely sensed data provides a spatial framework for investigating human impacts on the region. A geographic information system (GIS) integrates core analyses with historic data on land use change to yield a comprehensive land use and land cover framework and rates of change. These data resources establish the regional foundation for investigating the ecological components of an urban ecosystem. Urban-rural gradient analyses and patch analyses are proposed as the most appropriate methods for studying the urban ecosystem as they link ecological and social patterns and processes for varying degrees of urbanization.  相似文献   
662.
An analytical survey of man-machine interactive procedures is presented. A decision maker's capabilities to carry out some information processing operations are discussed. A list of a decision maker's elementary operations used in different interactive procedures is given and their estimations from a psychological point of view are suggested. Three main criteria for estimation of man-machine procedures are proposed: reliability of information elicitation from decision maker, insignificant sensitivity to random decision maker's errors, and good speed of convergence to solution. Some procedures are evaluated in terms of these criteria.  相似文献   
663.
The number of practicing behavior analysts who hold Behavior Analyst Certification Board (BACB) certification has substantially increased in the past decade. Some have mistakenly interpreted the BACB’s certification requirements as being specific to the autism and intellectual disabilities practice area. We present key BACB requirements, describe how they are practice-area neutral, and provide specific examples of their relevance to organizational behavior management.  相似文献   
664.
Prior literature indicates that although the sales function of an organization is a critical element for its success, there is a lack of research on specific actions managers can take to influence sales subordinates. The purpose of the present study was to assess the effects of a coaching package combined with incentives on sales performance for telemarketing personnel in an organizational setting. Following the implementation of the coaching package, there was a substantial increase in critical behaviors performed, pending sales set, and final sales completed by all telemarketers.  相似文献   
665.
The purpose of this research was to determine what behaviourally distinguishes effective and ineffective managers within a Moroccan Higher Education Institution (HEI). The critical incident technique (CIT) was the methodology deployed to collect data from participants in terms of how they perceive managers as either effective or ineffective. The collected data (CIs) were subjected to content and thematic analysis that resulted in derived positive and negative behavioural statements (BSs). A total of 42 participants/informants were interviewed and revealed a total of 418 CIs, of which 189 were positive CIs and 229 were negative. The analysis revealed a total of 49 BSs, of which 19 were positive and 30 were negative behavioural indicators. The findings of this investigation bring empirical evidence to understand what and how managers are perceived as effective or ineffective in the Moroccan academic context and, therefore, adds to the literature. The information obtained can also provide rich information/knowledge that can be used as a basis to address the behavioural developmental needs of managers in HEIs. This research adds value by following by following two previous replication studies in a French and a Hungarian HEI; moreover, this study is the first to be conducted in the Moroccan/North African region.  相似文献   
666.
A simple connected graph G with 2n vertices is said to be k-extendable for an integer k with \(0<k<n\) if G contains a perfect matching and every matching of cardinality k in G is a subset of some perfect matching. Lakhal and Litzler (Inf Process Lett 65(1):11–16, 1998) discovered a polynomial algorithm that decides whether a bipartite graph is k-extendable. For general graphs, however, it has been an open problem whether there exists a polynomial algorithm. The new result presented in this paper is that the extendability problem is co-NP-complete.  相似文献   
667.
Network coding is a generalization of conventional routing methods that allows a network node to code information flows before forwarding them. While it has been theoretically proved that network coding can achieve maximum network throughput, theoretical results usually do not consider the stochastic nature in information processing and transmission, especially when the capacity of each arc becomes stochastic due to failure, attacks, or maintenance. Hence, the reliability measurement of network coding becomes an important issue to evaluate the performance of the network under various system settings. In this paper, we present analytical expressions to measure the reliability of multicast communications in coded networks, where network coding is most promising. We define the probability that a multicast rate can be transmitted through a coded packet network under a total transmission cost constraint as the reliability metric. To do this, we first introduce an exact mathematical formulation to construct multicast connections over coded packet networks under a limited transmission cost. We then propose an algorithm based on minimal paths to calculate the reliability measurement of multicast connections and analyze the complexity of the algorithm. Our results show that the reliability of multicast routing with network coding improved significantly compared to the case of multicast routing without network coding.  相似文献   
668.
We describe a regression-based approach to the modelling of age-, order-, and duration-specific period fertility, using retrospective survey data. The approach produces results that are free of selection biases and can be used to study differential fertility. It is applied to Demographic and Health Survey data for Ethiopia, Kenya, Tanzania, and Zimbabwe to investigate differential trends in fertility by education. Parity progression fell and the intervals following each birth lengthened between the 1970s and 2000s in all four countries. Fertility fell most among women with secondary education. In contrast to other world regions, postponement of successive births for extended periods accounted for much of the initial drop in fertility in these African countries. However, family size limitation by women with secondary education in Ethiopia and Kenya and longer birth spacing in Zimbabwe also played significant roles. Thus, birth control is being adopted in Eastern Africa in response to diverse changes in fertility preferences.  相似文献   
669.
The authors investigated whether trends in attitudes about gender were consistent with the gender stall primarily occurring in the family domain and examined potential mechanisms associated with changing gender norms. Using data from Monitoring the Future surveys (1976–2015), the authors assessed three components of trends in youth's beliefs about gender: the marketplace, the family, and mothers' employment. Findings showed continued increases in egalitarianism from 1976 through the mid‐1990s across all three dimensions. Thereafter, support for egalitarianism in the public sphere plateaued at high levels, rising support for mothers' employment persisted at a slower pace, and conventional ideology about gender in families returned. The changing demographic composition of American high school students did not account for the gender attitude trends. Youth's mothers' employment and increased education were related to increased egalitarianism. Changes in population averages of mothers' employment and educational attainment were only weakly associated with increases in egalitarian attitudes.  相似文献   
670.
Funding decisions to support vulnerable children are tied to child labour statistics, hence the importance of an accurate measurement. The author analyses whether the type of respondent plays an important role in explaining variations in child labour statistics. Using data from two sites in Tanzania, the analysis shows that “whom we ask” matters considerably when estimating the prevalence of child labour. The results suggest that prevalence increases by approximately 35 to 65 per cent when using child self‐reports rather than proxy reports. This bias affects 14 to 31 per cent of the sample, depending on the indicator. Discrepancies decrease as the child ages and increase if proxy attitudes demonstrate opposition to child labour.  相似文献   
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