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21.
F. D. McDaniel B. L. Doyle C. H. Seager D. S. Walsh G. Vizkelethy D. K. Brice C. Yang P. Rossi M. Nigam M. El Bouanani G. V. Ravi Prasad J. C. Schwartz L. T. Mitchell J. L. Duggan 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2002,190(1-4):1-10
A new ion beam analysis-based, single ion technique called the time to first photon has been developed to measure the decay of the luminescence signal of phosphors. Such measurements are currently needed to study luminescence decay mechanisms following high-density excitations and to identify strongly luminescent phosphor coatings with short lifetimes for ion photon emission microscopy (IPEM). The samples for this technique consist of thin phosphor layers placed or coated on the surface of PIN diodes. Single ions from an accelerator strike this sample and simultaneously create ion beam induced luminescence (IBIL) from the phosphor that is measured by a single-photon-detector, and an ion beam induced charge collection (IBICC) signal in the PIN diode. In this case, the IBICC signal provides the start pulse and the IBIL signal the stop pulse to a time to amplitude converter. It is straightforward to show that this approach also measures a signal proportional to activity versus time with an accuracy of 5% as long as the number of detected photons per ion is less than 0.1, which usually requires the use of absorbers for the IBIL detector or electronic discrimination for the IBIL signals. Details of the new analysis are given together with examples of luminescence decay measurements of several ceramic phosphors being considered to coat IPEM samples. IPEM is currently being developed at Sandia National Laboratory (SNL), the University of North Texas in Denton, and the Universities and INFN of Padova and Torino. 相似文献
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The article presents a review of most important research results as well as opinions about the role and importance of body image disturbances in the development and the course of eating disorders. It also contains a review of definitions of body image, and techniques used in the evaluation of this type of disorders. 相似文献
23.
Proper integration of scheduling and control in Flexible Manufacturing Systems will make available the required level of decision-making capacity to provide a flexibly-automated, efficient, and quality manufacturing process. To achieve this level of integration, the developments in computer technology and sophisticated techniques of artificial intelligence (AI) should be applied to such FMS functions as scheduling. In this paper, we present an Intelligent Scheduling System for FMS under development that makes use of the integration of two AI technologies. These two AI technologies — Neural Networks and Expert Systems — provide the intelligence that the scheduling function requires in order to generate goodschedules within the restrictions imposed by real-time problems. Because the system has the ability to plan ahead and learn, it has a higher probability of success than conventional approaches. The adaptive behavior that will be achieved contribute to the integration of scheduling and control in FMS. 相似文献
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The aim of this study was to evaluate the effects of paste properties on residence time during drying in a spouted bed dryer with inert bodies. The effect of paste solids content, surface tension, and viscosity on the residence time distribution and the mean residence times were studied using factorial experimental designs. The inert bodies used were glass and polyethylene beads. The mean residence times varied from 13.6 to 16.3 and 12.2 to 17.7 min for drying on glass and polyethylene beads, respectively. The analysis of variance showed that mean residence times significantly depended on solids content and surface tension for glass beads and also on viscosity for polyethylene beads. The residence time distributions for all conditions studied fitted well to the perfect mixing cell when applying the continuous stirred vessels in series model analysis. The powder density, flowability, and particle size depended on paste properties and inert type. 相似文献
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Research on early childhood socialization suggests that Hispanic parents differ from parents of other ethnic groups in their child rearing values and the interpersonal behavior they want their children to display at home and school. In this article, the influence of context and culture on child rearing is shown through a review of conceptual frameworks for understanding child socialization in both minority and nonminority families and research on infant–mother attachment and parental beliefs about young children's behavior. This review indicates that parent and child behaviors are a result of different socialization processes that encompass specific cultural values. Implications for professional practice are drawn for child assessment and psychotherapy, family therapy, and parenting skills programs conducted with Hispanics. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Javier Lara-Romero Rafael Maya-Yescas José Luis Rico-Cerda José Luis Rivera-Rojas Fernando Chiñas Castillo Matey Kaltchev 《Thin solid films》2006,496(2):463-468
The thermal decomposition of model extreme-pressure lubricant additives on clean iron was studied in ultrahigh vacuum conditions using molecular beam strategies. Methylene chloride and chloroform react to deposit a solid film consisting of FeCl2 and carbon, and evolve only hydrogen into the gas phase. No gas-phase products and less carbon on the surface are detected in the case of carbon tetrachloride. Dimethyl and diethyl disulfide react on clean iron to deposit a saturated sulfur plus carbon layer at low temperatures (∼600 K) and an iron sulfide film onto a Fe + C underlayer at higher temperatures (∼950 K). Methane is the only gas-phase product when dimethyl disulfide reacts with iron. Ethylene and hydrogen are detected when diethyl disulfide is used. 相似文献
30.
José Luis García-Lapresta 《Information Sciences》2006,176(4):352-365
In this paper we have introduced a class of decision rules related to simple majority, by considering individual intensities of preference. These intensities will be shown by means of linguistic labels. In order to compare the amount of opinion obtained by each alternative, we have considered the total ordered monoid generated by the sums of the original labels, according to an addition and an ordering. In this general framework different sets of linguistic labels can be employed and these sets can be represented by means of diverse mathematical objects. Moreover, on these mathematical representations of linguistic labels several orderings can be considered. Thus, flexibility is an important feature of this new class of group decision making procedures. Some examples of putting in practice the simple majority decision rules based on linguistic labels are provided, and the main properties of these voting systems are analyzed. It is worth emphasizing that these properties are satisfied for any total ordered monoid, regardless of the mathematical representation of linguistic labels or the ordering used to compare collective opinions. 相似文献