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171.
Enabling a Powerful Marine and Offshore Decision-Support Solution Through Bayesian Network Technique 总被引:1,自引:1,他引:0
A powerful practical solution is by far the most desired output when making decisions under the realm of uncertainty on any safety-critical marine or offshore units and their systems. With data and information typically being obtained incrementally, adopting Bayesian network (BN) is shown to realistically deal with the random uncertainties while at the same time making risk assessments easier to build and to check. A well-matched methodology is proposed to formalize the reasoning in which the focal mechanism of inference processing relies on the sound Bayes's rule/theorem that permits the logic. Expanding one or more influencing nodal parameters with decision and utility node(s) also yields an influence diagram (ID). BN and ID feasibility is shown in a marine evacuation scenario and that of authorized vessels to floating, production, storage, and offloading collision, developed via a commercial computer tool. Sensitivity analysis and validation of the produced results are also presented. 相似文献
172.
Testing regression lack of fit without replication: a tutorial around Minitab's XLOF procedures 总被引:1,自引:1,他引:0
A. J. Lawrance 《Journal of applied statistics》1994,21(6):541-548
The tutorial is concerned with two types of test for the general lack of fit of a linear regression model, as found in the Minitab software package, and which do not require replicated observations. They aim to identify non-specified curvature and interaction in predictors, by comparing fits over the predictor region divided into two parts. Minitab's regression subcommand XLOF which gives the tests is only briefly documented in the manual and, unlike virtually all other statistical procedures in the software, it is not standard and cannot be readily found in textbooks. The two types of test are described here; they concern the predictors one-at-a-time and the predictors all-at-once. An example of their use is given. A suite of macros is available which reproduces the results of the XLOF tests in much more detail than is given by the XLOF subcommand. 相似文献
173.
John A. Eccleston Deborah J. Street 《Australian & New Zealand Journal of Statistics》1994,36(3):371-378
This paper presents an algorithm for the construction of optimal or near optimal change-over designs for arbitrary numbers of treatments, periods and units. Previous research on optimality has been either theoretical or has resulted in limited tabulations of small optimal designs. The algorithm consists of a number of steps:first find an optimal direct treatment effects design, ignoring residual effects, and then optimise this class of designs with respect to residual effects. Poor designs are avoided by judicious application of the (M, S)-optimality criterion, and modifications of it, to appropriate matrices. The performance of the algorithm is illustrated by examples. 相似文献
174.
Ego building is essentially a name given to a variety of interventions used to support an ego hampered by regression or deviation. The term has its roots in the concept of ego support but evolved specifically as a technical term in contemporary ego psychology closely connected with the developmental theory of separation individuation. Using four vignettes of psychotherapy work with children all of whom suffered from unresolved conflicts and developmental interferences from the separation-individuation process, an attempt is made to illustrate the technical place of ego building in psychotherapy with children. It is suggested that the use of ego building, particularly verbalizing adaptive aims facilitates an alliance, supports a safety feeling and positive self-esteem. This contributes to providing a treatment experience that reduces over-stimulation and anxiety and frees the expression and understanding of aggression which ultimately promotes separation-individuation.in private practice.This paper was presented at the Conference on the Continuing Evolution of Psychoanalytic Thought: Infancy to Adulthood, N.Y.C., Nov. 1990., sponsored by the Committee on Psychoanalysis of the National Federation of Societies for Clinical Social Work. 相似文献
175.
This article compares in regression models the effects of occupational status of both fathers and mothers simultaneously upon the attainment of men and women in the Irish Republic. The sample matches male respondents from the 1973/1974 Irish Mobility Study with the labour active female sibling next closest in age. Since the analysis compares working siblings and each 'matched pair' shares the same family origin characteristics, the problems attendant upon using a sample originally of men only are partially avoided. The results advance beyond previous research since, rather than separate models by gender, models include parents and children of both genders, allowing direct rather than indirect evaluation of gender-based determinants of occupational attainment. Both fathers and mothers significantly affect children's attainment, in ways that vary by the child's gender. The results highlight the salience of mothers' attainment for their children and question the 'mainstream' model of equivalent mechanisms of occupational attainment for both genders. Models of social mobility that consider men and women as special instances of a general perspective provide the most fruitful approach for further development. 相似文献
176.
177.
This study examines the effect of unionization, right-to-work laws, and participation of women in the labor force on income
inequality. Two distinct models are developed using 1970 and 1980 census data on the 50 states in the U.S. First, an income
inequality model is specified as a beta distribution of the second kind to estimate Gini measures of income inequality. Second,
these Gini estimates are used in a simultaneous equations model. The 1970 results indicate that higher unionization rates
decreased inequality while right-to-work laws increased inequality. In 1980, the measure of inequality was lower in states
with higher female labor force participation.
We thank an unknown referee and the editor for comments and criticisms that greatly improved the paper. The usual caveat applies. 相似文献
178.
179.
In this paper, the notion of average total inspection (ATI) is introduced to ChSP-4(c1,c2) sampling plans. Procedures have been developed for the construction and selection of ChSP-4(c1, c2 plans, minimizing ATI at a given process average, while protection to the consumer is given in terms of the (i) average outgoing quality limit and (ii) limiting quality level.A wide range of c1 and c2 values are considered for developing tables which cover almost all practical situations. The procedure described is similar to that of Dodge and Romig. 相似文献
180.
SONET (Synchronous Optical NETworks) add-drop multiplexers (ADMs) are the dominant cost factor in the WDM(Wavelength Division Multiplexing)/SONET rings. The number of SONET ADMs required by a set of traffic streams is determined by the routing and wavelength assignment of the traffic streams. Previous works took as input the traffic streams with routings given a priori and developed various heuristics for wavelength assignment to minimize the SONET ADM costs. However, little was known about the performance guarantees of these heuristics. This paper contributes mainly in two aspects. First, in addition to the traffic streams with pre-specified routing, this paper also studies minimizing the ADM requirement by traffic streams without given routings, a problem which is shown to be NP-hard. Several heuristics for integrated routing and wavelength assignment are proposed to minimize the SONET ADM costs. Second, the approximation ratios of those heuristics for wavelength assignment only and those heuristics for integrated routing and wavelength assignment are analyzed. The new Preprocessed Iterative Matching heuristic has the best approximation ratio: at most 3/2. 相似文献