865 resultados para Susskind, Leonard: The Cosmic Landscape: string theory and the illusion of intelligent design


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Reef managers cannot fight global warming through mitigation at local scale, but they can use information on thermal patterns to plan for reserve networks that maximize the probability of persistence of their reef system. Here we assess previous methods for the design of reserves for climate change and present a new approach to prioritize areas for conservation that leverages the most desirable properties of previous approaches. The new method moves the science of reserve design for climate change a step forwards by: (1) recognizing the role of seasonal acclimation in increasing the limits of environmental tolerance of corals and ameliorating the bleaching response; (2) including information from several bleaching events, which frequency is likely to increase in the future; (3) assessing relevant variability at country scales, where most management plans are carried out. We demonstrate the method in Honduras, where a reassessment of the marine spatial plan is in progress.

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A host of studies over the years have been published on introductions to research articles across a variety of fields. However, much less attention has been paid to professional or workplace introductions as well as student written introductions. This study aims to redress this imbalance by studying the writing samples of four primary English teacher trainees’ introductions to curricular design i.e. the document candidates must present to an examination board in Spain. This genre can be considered occluded in that exemplars are private and confidential and not readily available to the aspiring candidate. Three recurrent moves were identified, namely, explaining the importance of curricular design, providing background and defining concepts. Instances of self-glorification (Bhatia 1996) were revealed. The implications of the findings can have a positive effect on students’ future writing. RESUMEN. Se han publicado varios estudios en los últimos años sobre las introducciones de los artículos de investigación en varios campos. Sin embargo, se ha prestado mucha menor atención a las introducciones en los ámbitos profesionales o las introducciones en el lugar de trabajo, así como a las introducciones escritas por estudiantes. Este estudio tiene por objeto corregir este desequilibrio mediante el análisis de cuatro introducciones redactadas por candidatos para las oposiciones públicas de profesores de inglés de primaria. Este género se puede considerar oculto puesto que las muestras de dichas introducciones no están publicadas. El análisis de estas introducciones muestra que hay tres movimientos recurrentes: una explicación de la importancia del diseño curricular, definición del contexto educativo y, por último, definición de conceptos. Hay ejemplos en este estudio empírico de auto-promoción (Bhatia 1996). Las implicaciones de los resultados pueden tener un efecto positivo en la escritura de estos estudiantes en el futuro.

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Thesis (Master's)--University of Washington, 2016-06

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The power required to operate large gyratory mills often exceeds 10 MW. Hence, optimisation of the power consumption will have a significant impact on the overall economic performance and environmental impact of the mineral processing plant. In most of the published models of tumbling mills (e.g. [Morrell, S., 1996. Power draw of wet tumbling mills and its relationship to charge dynamics, Part 2: An empirical approach to modelling of mill power draw. Trans. Inst. Mining Metall. (Section C: Mineral Processing Ext. Metall.) 105, C54-C62. Austin, L.G., 1990. A mill power equation for SAG mills. Miner. Metall. Process. 57-62]), the effect of lifter design and its interaction with mill speed and filling are not incorporated. Recent experience suggests that there is an opportunity for improving grinding efficiency by choosing the appropriate combination of these variables. However, it is difficult to experimentally determine the interactions of these variables in a full scale mill. Although some work has recently been published using DEM simulations, it was basically. limited to 2D. The discrete element code, Particle Flow Code 3D (PFC3D), has been used in this work to model the effects of lifter height (525 cm) and mill speed (50-90% of critical) on the power draw and frequency distribution of specific energy (J/kg) of normal impacts in a 5 m diameter autogenous (AG) mill. It was found that the distribution of the impact energy is affected by the number of lifters, lifter height, mill speed and mill filling. Interactions of lifter design, mill speed and mill filling are demonstrated through three dimensional distinct element methods (3D DEM) modelling. The intensity of the induced stresses (shear and normal) on lifters, and hence the lifter wear, is also simulated. (C) 2004 Elsevier Ltd. All rights reserved.

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This thesis reports the development of a reliable method for the prediction of response to electromagnetically induced vibration in large electric machines. The machines of primary interest are DC ship-propulsion motors but much of the work reported has broader significance. The investigation has involved work in five principal areas. (1) The development and use of dynamic substructuring methods. (2) The development of special elements to represent individual machine components. (3) Laboratory scale investigations to establish empirical values for properties which affect machine vibration levels. (4) Experiments on machines on the factory test-bed to provide data for correlation with prediction. (5) Reasoning with regard to the effect of various design features. The limiting factor in producing good models for machines in vibration is the time required for an analysis to take place. Dynamic substructuring methods were adopted early in the project to maximise the efficiency of the analysis. A review of existing substructure- representation and composite-structure assembly methods includes comments on which are most suitable for this application. In three appendices to the main volume methods are presented which were developed by the author to accelerate analyses. Despite significant advances in this area, the limiting factor in machine analyses is still time. The representation of individual machine components was addressed as another means by which the time required for an analysis could be reduced. This has resulted in the development of special elements which are more efficient than their finite-element counterparts. The laboratory scale experiments reported were undertaken to establish empirical values for the properties of three distinct features - lamination stacks, bolted-flange joints in rings and cylinders and the shimmed pole-yoke joint. These are central to the preparation of an accurate machine model. The theoretical methods are tested numerically and correlated with tests on two machines (running and static). A system has been devised with which the general electromagnetic forcing may be split into its most fundamental components. This is used to draw some conclusions about the probable effects of various design features.

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Investigation of the different approaches used by Expert Systems researchers to solve problems in the domain of Mechanical Design and Expert Systems was carried out. The techniques used for conventional formal logic programming were compared with those used when applying Expert Systems concepts. A literature survey of design processes was also conducted with a view to adopting a suitable model of the design process. A model, comprising a variation on two established ones, was developed and applied to a problem within what are described as class 3 design tasks. The research explored the application of these concepts to Mechanical Engineering Design problems and their implementation on a microcomputer using an Expert System building tool. It was necessary to explore the use of Expert Systems in this manner so as to bridge the gap between their use as a control structure and for detailed analytical design. The former application is well researched into and this thesis discusses the latter. Some Expert System building tools available to the author at the beginning of his work were evaluated specifically for their suitability for Mechanical Engineering design problems. Microsynics was found to be the most suitable on which to implement a design problem because of its simple but powerful Semantic Net Knowledge Representation structure and the ability to use other types of representation schemes. Two major implementations were carried out. The first involved a design program for a Helical compression spring and the second a gearpair system design. Two concepts were proposed in the thesis for the modelling and implementation of design systems involving many equations. The method proposed enables equation manipulation and analysis using a combination of frames, semantic nets and production rules. The use of semantic nets for purposes other than for psychology and natural language interpretation, is quite new and represents one of the major contributions to knowledge by the author. The development of a purpose built shell program for this type of design problems was recommended as an extension of the research. Microsynics may usefully be used as a platform for this development.

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Product design decisions can have a significant impact on the financial and operation performance of manufacturing companies. Therefore good analysis of the financial impact of design decisions is required if the profitability of the business is to be maximised. The product design process can be viewed as a chain of decisions which links decisions about the concept to decisions about the detail. The idea of decision chains can be extended to include the design and operation of the 'downstream' business processes which manufacture and support the product. These chains of decisions are not independent but are interrelated in a complex manner. To deal with the interdependencies requires a modelling approach which represents all the chains of decisions, to a level of detail not normally considered in the analysis of product design. The operational, control and financial elements of a manufacturing business constitute a dynamic system. These elements interact with each other and with external elements (i.e. customers and suppliers). Analysing the chain of decisions for such an environment requires the application of simulation techniques, not just to any one area of interest, but to the whole business i.e. an enterprise simulation. To investigate the capability and viability of enterprise simulation an experimental 'Whole Business Simulation' system has been developed. This system combines specialist simulation elements and standard operational applications software packages, to create a model that incorporates all the key elements of a manufacturing business, including its customers and suppliers. By means of a series of experiments, the performance of this system was compared with a range of existing analysis tools (i.e. DFX, capacity calculation, shop floor simulator, and business planner driven by a shop floor simulator).

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Objective: To establish the best predictors of maternal use of controlling feeding practices at 1 and 2 years of age. Design: A longitudinal study from birth to 2 years. Participants: Sixty-two mothers of 2-year-old children. Measures: Infant weight at birth, 6, 12 and 24 months, breastfeeding history, infant temperament and feeding difficulties at 6 and 12 months, maternal demographics at 12 and 24 months, maternal mental health at 6 and 12 months, maternal controlling feeding practices at 12 and 24 months. Results: Controlling feeding practices at 1 year were predicted by perceptions of infant temperament at 6 months, birth weight, length of breastfeeding, mental health at 6 months, and mealtime negativity at 6 months. Parental control over feeding when their child reached 2 years was predicted by the mother's tendency to use that particular strategy at 1 year in combination with the perceptions of infant temperament and feeding problems at 1 year, weight at 1 year, length of breastfeeding in infancy, and/or maternal mental health at 1 year. Conclusions: Breastfeeding appears to promote subsequent monitoring, and is associated with reduced use of pressurising and restrictive feeding practices. Infant characteristics are important predictors of control at both 1 and 2 years of age. The use of controlling feeding practices is relatively stable from 1 to 2 years. © 2007 Nature Publishing Group All rights reserved.

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The purpose of the study was to examine the relationship between teacher beliefs and actual classroom practice in early literacy instruction. Conjoint analysis was used to measure teachers' beliefs on four early literacy factors—phonological awareness, print awareness, graphophonic awareness, and structural awareness. A collective case study format was then used to measure the correspondence of teachers' beliefs with their actual classroom practice. ^ Ninety Project READS participants were given twelve cards in an orthogonal experimental design describing students that either met or did not meet criteria on the four early literacy factors. Conjoint measurements of whether the student is an efficient reader were taken. These measurements provided relative importance scores for each respondent. Based on the relative important scores, four teachers were chosen to participate in a collective case study. ^ The conjoint results enabled the clustering of teachers into four distinct groups, each aligned with one of the four early literacy factors. K-means cluster analysis of the relative importance measurements showed commonalities among the ninety respondents' beliefs. The collective case study results were mixed. Implications for researchers and practitioners include the use of conjoint analysis in measuring teacher beliefs on the four early literacy factors. Further, the understanding of teacher preferences on these beliefs may assist in the development of curriculum design and therefore increase educational effectiveness. Finally, comparisons between teachers' beliefs on the four early literacy factors and actual instructional practices may facilitate teacher self-reflection thus encouraging positive teacher change. ^

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This paper describes the evolution of a ‘Design - Build-Fly’ (DBF) approach to the delivery and assessment of a Stage Three Aircraft Design module. It focuses on the primary learning outcomes around the design and manufacturing functions associated with the development of a remotely controlled aircraft. The work covers a six year period from 2011 to present mapping the transformation of the module from report based assessment to a more hands on approach resulting in a fully functioning remotely controlled aircraft. Results show that both the staff and student experience improved across key performance metrics including student feedback, learning and competency development. Challenges still remain in methods of placing students within teams and maintaining technical rigour in reporting as students develop vocational skills and more reflective writing styles.

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The investigations for this report were initiated in October, 1967, to perform the following: l. Review the current Iowa State Highway Commission roadway geometric design standards and criteria for conformance with national policies and recent research findings with special attention to high way safety. 2. Review the current Iowa State Highway Commission roadway lighting design standards and criteria for conformance with national policies and recent research findings with special attention to high way safety

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Neonatal seizures are common in the neonatal intensive care unit. Clinicians treat these seizures with several anti-epileptic drugs (AEDs) to reduce seizures in a neonate. Current AEDs exhibit sub-optimal efficacy and several randomized control trials (RCT) of novel AEDs are planned. The aim of this study was to measure the influence of trial design on the required sample size of a RCT. We used seizure time courses from 41 term neonates with hypoxic ischaemic encephalopathy to build seizure treatment trial simulations. We used five outcome measures, three AED protocols, eight treatment delays from seizure onset (Td) and four levels of trial AED efficacy to simulate different RCTs. We performed power calculations for each RCT design and analysed the resultant sample size. We also assessed the rate of false positives, or placebo effect, in typical uncontrolled studies. We found that the false positive rate ranged from 5 to 85% of patients depending on RCT design. For controlled trials, the choice of outcome measure had the largest effect on sample size with median differences of 30.7 fold (IQR: 13.7–40.0) across a range of AED protocols, Td and trial AED efficacy (p<0.001). RCTs that compared the trial AED with positive controls required sample sizes with a median fold increase of 3.2 (IQR: 1.9–11.9; p<0.001). Delays in AED administration from seizure onset also increased the required sample size 2.1 fold (IQR: 1.7–2.9; p<0.001). Subgroup analysis showed that RCTs in neonates treated with hypothermia required a median fold increase in sample size of 2.6 (IQR: 2.4–3.0) compared to trials in normothermic neonates (p<0.001). These results show that RCT design has a profound influence on the required sample size. Trials that use a control group, appropriate outcome measure, and control for differences in Td between groups in analysis will be valid and minimise sample size.

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Artificial reefs are used as management tools for coastal fisheries and ecosystems and the knowledge of habitat use and fish movements around them is necessary to understand their performance and improve their design and location. In this study wild specimens of Diplodus sargus were tagged with acoustic tags and their movements were tracked using passive acoustic telemetry. The monitored area enclosed a natural rocky reef, an adjacent artificial reef (AR) and shallower sandy bottoms. Most of the fish were close to full time residents in the monitored area. Results revealed that D. sargus use the natural reef areas on a more frequent basis than the AR. However, excursions to the adjacent AR and sandy bottoms were frequently detected, essentially during daytime. The use of acoustic telemetry allowed a better understanding of the use of artificial reef structures and its adjacent areas by wild D. sargus providing information that is helpful towards the improvement of AR design and location. (c) 2013 Elsevier Ltd. All rights reserved.