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821.
This article describes an application of a method for assessing risks associated with the introduction of an organism into a new environment. The test organism was a binucleate Rhizoctonia fungal isolate that has potential for commercial development as a biological control agent for damping-off diseases in bedding plants. A test sample of host plant species was selected using the centrifugal phylogenetic host range principles, but with an emphasis on economic species. The effect of the fungus on the plant was measured for each species and expressed on a logarithmic scale. The effects on weights of shoots and roots per container were not normally distributed, nor were the effects on the number of plants standing (those which survived). Statements about the effect on the number standing and the shoot weight per container involved using the observed (empirical) distribution. This is illustrated with an example. Problems were encountered in defining the population of species at risk, and in deciding how this population should be formally sampled. The limitations of the method are discussed. 相似文献
822.
The Regional Meteorological Service for the Emilia-Romagna Region manages a network of automatic weather stations equipped with electronic sensors suitable for measuring meteorological parameters. The automatic stations consist of electronic instruments, which are subject to failures at more or less frequent intervals. A summary of their performance is necessary. In this paper, we compare the results of the summary, such as the contiguous absence or simultaneous inactivity of different stations, with theoretical simulations in order to evaluate the nature and recurrence of the failures. A single- and multi-server queue simulation model was also used to evaluate the performance of the data transmission system, so as to optimize the communications system. 相似文献
823.
Summary In foster care research the focus is generally placed on thechildren, not on the parents who perform the foster care. Inthis article the focus is on foster parents of 10-11 year-oldchildren. They were interviewed about their motives for becomingfoster parents, which were linked to their family and work circumstances.Among the 21 foster families in the study, four different butequally frequent reasons or motives for taking care of fosterchildren from the very beginning could be distinguished: relativeswho feel responsibility for a certain child; couples who wantchildren and do not think they can have children of their own;families where the mother wants to be at home taking care ofbiological as well as foster children instead of having unskilledemployed work outside the home; and parents with grown-up childrenwho want to fill the 'empty nest' by becoming foster parents- combined with a family business at home or close to home.Changing family and work patterns in Sweden do not seem to haveinfluenced foster families as much as families in general. Theworth of acquiring more knowledge about the families involvedin foster care of children and young people in order to improvefoster care and reduce breakdowns of care is discussed. 相似文献
824.
Common foundations which underlie thinking in the supply chain management (SCM), Business process re-engineering (BPR) and business process improvement (BPI) philosophies are highlighted. The view that BPR is a new concept is argued against by highlighting die work performed in other fields, namely SCM from the systems perspective. It is argued that those who have already implemented the SCM philosophy will have already travelled the same path as BPR and indeed re-engineered their own processes. Once businesses have integrated their supply chain the greatest benefits will have already been achieved, however system dynamics analysis does show significant on-cost differences dependent on the redesign strategy implemented. A generic structured model for SCM is enhanced through this comparison with BPR with the following characteristics being added; do not be afraid to be radical with respect to internal integration and continually search for step change improvement ideas which can be strategically phased in to positively impact the marketplace. 相似文献
825.
K.G. Janardan 《统计学通讯:理论与方法》2013,42(10):2423-2442
Janardan (1973) introduced the generalized Polya Eggenberger family of distributions (GPED) as a limiting distribution of the generalized Markov-Polya distribution (GMPD). Janardan and Rao (1982) gave a number of characterizing properties of the generalized Markov-Polya and generalized Polya Eggenberger distributions. Here, the GPED family characterized by four parameters, is formally defined and studied. The probability generating function, its moments, and certain recurrence relations with the moments are provided. The Lagrangian Katz family of distributions (Consul and Famoye (1996)) is shown to be a sub-class of the family of GPED (or GPED 1 ) as it is called in this paper). A generalized Polya Eggenberger distribution of the second kind (GPED 2 ) is also introduced and some of it's properties are given. Recurrence relations for the probabilities of GPED 1 and GPED 2 are given. A number of other structural and characteristic properties of the GPED 1 are provided, from which the properties of Lagrangian Katz family follow. The parameters of GMPD 1 are estimated by the method of moments and the maximum likelihood method. An application is provided. 相似文献
826.
827.
828.
Row-column designs may be considered to have two blocking schemes, namely the treatments by rows and treatments by columns component block designs. The (M,S)-optimality criterion is applied to row-column designs, and che connection between the (M,S)-optimal design and its component block designs is demonstrated. 相似文献
829.
830.
Dorinda N. Noble Kathleen Perkins Marian Fatout 《Child and Adolescent Social Work Journal》2000,17(2):141-153
Strength coaches help athletes assess their strengths and build on them. Likewise, social workers dealing with children and families in the child welfare system, rather than looking for pathology, can learn to help clients discover and develop their strengths, even while dealing with a child welfare bureaucracy. This article gives examples of the strength coach approach. 相似文献