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61.
Leischow Scott J.; Valente Suzanne N.; Hill Anabel L.; Otte Pamela S.; Aickin Mikel; Holden Timothy; Kligman Evan; Cook Gretchen 《Canadian Metallurgical Quarterly》1997,5(1):54
The effects of using several different nicotine replacement treatments on self-reported withdrawal symptoms and side effects during 2-day periods of smoking cessation, with 5 days of ad lib smoking between cessation days, were evaluated. Participants (N ?=?18) experienced the following conditions: nicotine gum, 24-hr patch, 16-hr patch, 24-hr patch plus gum, double 24-hr patch, and no nicotine replacement. The present study found morning urge to smoke was greater during the 16-hr than during the 24-hr patch condition. Double-patch use resulted in significantly greater insomnia than the smoking baseline and 16-hr patch conditions. The no medication and gum alone conditions resulted in similar withdrawal symptoms, and both tended to result in greater reported withdrawal symptoms than the smoking baseline condition. There were no significant withdrawal symptom differences between the 24-hr, patch-gum, and double-patch conditions. The 24-hr and double-patch conditions were preferred by two thirds of the participants (6 each). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The need for a suitable classification of media types arises for several reasons when building or comparing multimedia systems. Within an Intelligent Multimedia Presentation Systems (IMMPS), it is necessary to formulate and encode design knowledge for decision making on the appropriate medium in which to present information and for the generation of the presentation. It is also required in order to specify interfaces to and between system components which will be employed to run a generated presentation before the user's eyes. This task is reflected in the Standard Reference Model (SRM, see this volume) for IMMPS by the Presentation Display Layer. However, the SRM does not instantiate this layer in detail, but instead refers to the Presentation Environment for Multimedia Objects (PREMO) ISO/IEC standard which provides a reference model for a presentation runtime environment for multimedia. PREMO already contains a set of basic structures, the so-called PREMO Primitive Hierarchy, to describe different media types. Thus the question arises, as to how far the PREMO Primitive Hierarchy could serve as a media classification for the SRM in general. In particular, this would support consistency between the design and presentation layers of the SRM if PREMO were used to instantiate the presentation layer. In the current paper, we first point to a number of typical problems with generating classifications of media types. We then provide a brief introduction to PREMO and its Primitive Hierarchy. Finally, the benefits and costs of using the PREMO Primitive Hierarchy for the SRM are discussed. 相似文献
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The effect of 30–49 wt-% nitrile group content on the properties of copolymers is demonstrated. The nitrile is furnished by either acrylonitrile or methacrylonitrile. The exceptional resistance of such high nitrile content resins to the passage of gases and of solvents is shown and variations therein demonstrated for different comonomers. Transparent, tough, grafted polymers of good color are described which retain these properties. These qualities, combined with low second-order transition temperatures and adequate heat deflection temperatures, provide polymers of interest wherever containment and barrier are desired. Bottles, thermoformed containers, etc., could benefit from the use of some of the polymers described. 相似文献
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To test the possibility that certain factors may mediate the locus of control (Adult Nowicki-Strickland Internal–External Control Scale) of reinforcement/achievement relation, 80 male and 80 female college students in Exp I were asked to compete against or cooperate with same- or opposite-sex partners. The hypothesis that the achievement behavior of internally controlled females would be more affected by sex of partner and type of competition than that of males was confirmed and replicated in Exp II with 60 female college students. Although internally controlled males increased their achievement more than did externally controlled males, internally controlled females increased their performance when competing against males or cooperating with females. These results are interpreted as meaning that females may require more complex models to describe their behavior in general and the locus of control/achievement relation in particular. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Using the framework of J. B. Rotter's social learning theory, it was predicted that the specific and generalized expectancies of 315 college student counseling clients would clarify their counseling goals and would be related to length of time spent in counseling as well as to rated positiveness of the counseling experience. Data from a specially constructed specific expectancy questionnaire and from a measure of the generalized expectancy of locus of control of reinforcement (Adult Nowicki-Strickland Internal–External Control Scale) confirm these predictions. Clients had stable expectancies regarding the counseling process; internals as compared to externals presented different counseling problems, stayed in counseling a shorter time, but were rated as more improved. In addition, those clients who dropped out of counseling after the intake were internal in their locus-of-control orientation. Various practical applications of the results are discussed as well as directions for future research within the framework of social learning theory. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The stiffness of yaw and pitch slewing bearings has a critical influence on the structural behaviour of wind turbine generators. Thus, it is commonly required by designers for their simulations to estimate deformations and select the most suitable bearing for their working conditions in preliminary design stages. In this work, a design of experiments was carried out via finite element analysis to obtain the stiffness curves of all of the standard four‐point contact slewing bearings from the catalogues of manufacturers under radial, axial, and tilting loads. From these results, a set of simple formulas to calculate the ring deformations were adjusted. Combining them with contact deformation results obtained in previous work by the authors, a complete and efficient tool for slewing bearing stiffness estimation has been developed. 相似文献
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Polymers beyond standard optical fibres – fabrication of microstructured polymer optical fibres
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Eneko Arrospide Gaizka Durana Mikel Azkune Gotzon Aldabaldetreku Iñaki Bikandi Leire Ruiz‐Rubio Joseba Zubia 《Polymer International》2018,67(9):1155-1163
This paper reports the overall fabrication process of microstructured polymer optical fibres (mPOFs). mPOF fabrication involves a two‐step process: on the one hand, the design and creation of a preform containing a large‐scale version of the desired fibre and, on the other, the precise heating and drawing of the preform to the final fibre. The preforms are produced either by an improved drilling technique or by capillary stacking. For a correct and accurate drawing of the fibre, a controlled and precise heating unit has to be designed, an issue that will be explained in detail in this work. The quality and optical performance of the final mPOF depends strongly on key factors such as the preform annealing, the accuracy of the technique selected for the creation of the preform structure, the heating stage, as well as on the drawing parameters. All of them are analysed in detail and some drawn mPOFs of interest are reported as well. © 2018 Society of Chemical Industry 相似文献
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