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51.
This research tested the thesis that adolescent problem drinking may be manifest in any of four independent domains (measured by the 24-item screening instrument, the Adolescent Drinking Inventory: Drinking and You): drinking-related loss of control, social indicators, psychological indicators, and physical indicators. Clinical assessments of 264 adolescents referred for screening revealed that more than half of the variation in clinical assessment of problem drinking severity was captured by these four domains and that two of the four domains (loss of control and psychological indicators) made an independent contribution to clinical assessment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
52.
This paper extends a method for modeling the survival of patients in hospitals to allow the expected cost to be estimated for the patients' accumulated duration of time in care. An extension of Bayesian network (BN) theory has previously been developed to model patients' survival time in hospitals with respect to the graphical and probabilistic representation of the interrelationships between the patients' clinical variables. Unlike previous BN techniques, this extended model can accommodate continuous times that are skewed in nature. This paper presents the theory behind such an approach and extends it by attaching a cost variable to the survival times, enabling the costing and efficient management of groups of patients in hospitals. An application of the model is illustrated by considering a group of 4260 patients admitted into the geriatric department of a U.K. hospital between 1994-1997. Results are derived for the distribution for their length of stay in the hospital and associated costs. The model's practical use is highlighted by illustrating how hospital managers could benefit using such a method for investigating the influence of future decisions and policy changes on the hospital's expenditure.  相似文献   
53.
This paper describes the first working version of a program called Dominic that performs design by iterative redesign in a domain-independent manner. The paper describes in detail the program's strategy, which stresses the concept of redesign dependencies to guide its redesign process. Dominic has been successfully tested in four different domains. Its performance on two of these (v-belt drive design and design of extruded heat sinks) is presented here. The redesign class of design problems on which Dominic works is that large class of problems that are intellectually manageable and solvable without subdivision into smaller parts. This includes the various subproblems ultimately created when large complex problems are decomposed for solution. Dominic is a hill-climbing algorithm, similar in this respect to standard optimization methods. However, its problem formulation or input language is more flexible for some design applications than optimization techniques. Work is continuing on a Dominic II in an effort to overcome some of the limitations of Dominic.  相似文献   
54.
This is the third in a series of articles that describe, through examples, how the Scientific Applications and Visualization Group (SAVG) at NIST has utilized high performance parallel computing, visualization, and machine learning to accelerate scientific discovery. In this article we focus on the use of high performance computing and visualization for simulations of nanotechnology.  相似文献   
55.
The hydrodynamic feasibility of a proposed third inlet to East Matagorda Bay, Texas, was examined by application of a two-dimensional, depth-averaged hydrodynamic model. Wind-driven flows in this remote, shallow bay frequently dominate the weak astronomical tide. The bay presently has two connections to the Gulf of Mexico, one through a short flood-relief channel and the other through a long and circuitous navigation channel. The study had to consider whether installation of a third inlet would cause the relief channel to close or increase the already strong current velocity in the navigation channel that is a concern for boating safety. The model was calibrated with measurements of wind, water level, and current taken in this study. It is concluded that the new inlet will be ebb-dominated because of the wind-induced current, and that the relief channel will not close in the presence of the new inlet. In addition, the peak current at a critical maneuvering area in the navigation channel that presently poses a hazard to vessel traffic will be reduced by as much as 25% as a result of opening the new inlet.  相似文献   
56.
This article presents two high‐temperature thermoplastic powders which were sintered by spark plasma sintering in order to get homogeneous mechanical properties. Dense polyimide (PI) and polyetheretherketone (PEEK) specimens were obtained at temperatures as low as 320°C for PI and 200°C for PEEK, respectively. Relative densities higher than 99% were reached for both materials. In order to characterize their properties, in situ measurements with compression and hardness tests were carried out on sintered samples. This method allowed to obtain polymeric materials with improved mechanical properties. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40783.  相似文献   
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The water-soluble poly{trimethyl-[7-(3-thienylsulfanyl)heptyl]ammonium iodide-co-thiophene} (PTN+Me3) forms aggregates whose size span a large range of values, depending on solvent, concentration and film formation conditions. Larger aggregates were detected by atomic force microscopy and dynamic light scattering, smaller ones by DOSY NMR, UV–visible and fluorescence. All techniques indicate a reduced aggregation of PTN+Me3 in DMSO relative to water and a marked de-aggregation of PTN+Me3 in water following addition of bile-acid anions such as deoxycholate and ursodeoxycholate. The latter effect shows itself through a very large enhancement of the polymer photoluminescence likely caused by disruption of aggregated non-emissive exciton traps. A tailored combination of electrostatic and hydrophobic interactions between the polymer and the bile-acid anions seems to be necessary to achieve this effect. These observations suggest that this polythiophene might provide a basis for the development of fluorescent sensors suitable for the detection of medium-sized amphiphilic biomolecules.  相似文献   
60.
Two aspects of continuity, stability of individual differences and means, were examined in a longitudinal study from the middle elementary through the high school years. Two hypotheses regarding individual difference stability were supported with structural equation modeling in both the general-verbal and math domains: (a) Academic intrinsic motivation is a stable construct throughout these years, and (b) with advancement in age, academic intrinsic motivation becomes increasingly stable. A third hypothesis, that the mean level of academic intrinsic motivation declines over these ages, also was supported, and significant linear trends were obtained, but it was also found to be modified by particular subject areas, with math showing the greatest decline and social studies showing no significant change. The combination of these 2 aspects of continuity places those with low motivation early in their schooling particularly at risk. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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