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61.
E. A. Chinnov F. V. Ron’shin V. V. Guzanov D. M. Markovich O. A. Kabov 《High Temperature》2014,52(5):681-687
Two-phase flow in a rectangular short horizontal channel 200 μm high was studied experimentally. The use of the fluorescent method made it possible to reveal flow of liquid in the channel and to determine its characteristics quantitatively. The existence of the regime of separate (stratified) flow is established. Based on analysis of previous investigations and newly obtained data, it is shown that a change in the height of the horizontal channel has a substantial effect on the boundaries between the regimes. The region of the churn regime increases with decreasing thickness of the channel. 相似文献
62.
Ron Sun 《人工智能实验与理论杂志》2018,30(1):13-37
This paper discusses, in the context of computational modelling and simulation of cognition, the relevance of deeper structures in the control of behaviour. Such deeper structures include motivational control of behaviour, which provides underlying causes for actions, and also metacognitive control, which provides higher-order processes for monitoring and regulation. It is argued that such deeper structures are important and thus cannot be ignored in computational cognitive architectures. A general framework based on the Clarion cognitive architecture is outlined that emphasises the interaction amongst action selection, motivation, and metacognition. The upshot is that it is necessary to incorporate all essential processes; short of that, the understanding of cognition can only be incomplete. 相似文献
63.
64.
Modern technology is affecting what is taught and how statistics is taught. Computer intensive methods like bootstrapping, generalized regression, coordinate exchange algorithms and computer experiment emulators are now part of the statistical toolkit. In parallel with these new methods and tools, a similar evolution appears in statistical education. Simulators offer opportunities for hands-on experience in the classroom, bridging the gap between theory and practice. In this article, we map a wide range of simulation based tools used in teaching statistical methods, putting them in the context of a quality ladder representing various maturity levels of organizations and course level sophistication. The mapping is designed to help educators assess and integrate options related to the incorporation of simulators as teaching aids in an educational and pedagogical roadmap. The mapping is applied to specific simulation products but provides a general framework that can be expanded and used in a generic way. 相似文献
65.
66.
Ron Craig 《Construction Management & Economics》2013,31(1):91-100
The UK's NJCC Code of Procedure for Single Stage Selective Tendering (now withdrawn) and its successor, the CIB's Code of Practice for the Selection of Main Contractors are criticized in the light of decisions of the common law courts with regard to regulation of the tendering process. It is argued that a new ‘Tendering Code’ should be produced in the style and format of a contract document which reflects not only the statutory regulation imposed on public bodies, but common law decisions of the courts. The nature of this tendering contract is explained as a means of regulating the tendering process. Issues discussed are: dealing with errors and irregularities found in tenders; dealing with non-compliant tenders; dealing with tender withdrawal prior to its acceptance or rejection; making provisions as to time for submission of tenders and dealing with late tenders; making provision for submission of tender by fax or other electronic means; making provision for evaluation of tenders received; and imposing or negotiating reductions in price with tenderers prior to acceptance. The paper concludes that the common law obligations placed on the owner to treat all tenderers equally and fairly and to apply the tender conditions when evaluating tenders and awarding contracts seems to be good common sense and of commercial advantage, not only to the immediate parties concerned but also to the wider community. 相似文献
67.
什么是数字合成?当我们讨论它的时候,首先我们试着把多个元素整合成一个单个的完整的整体图像,当大多数这些技术仍然适用于图像时,我们将关注有用的和合理的能处理大的图像序列的工具和方法。正如您所见的,一个技术很好的合成师是可以包括从技师到艺术家的,不只是需要基本了解“操作的工具”,这里包括多种软件,而且必须是一个能洞察视觉本质的人。记住这一点,当遇到“它看起来是否正确?”的问题时,所有技术考虑都是不重要了,很明显只是一个对主题的把握,同时一个好的合成师都应以高要求来做出每个决定。定义什么是合成?有一个基本的定义:把… 相似文献
68.
Dioxins and dioxin-like (DL) polychlorinated biphenyls (PCB) are persistent organic pollutants that enter the body mainly by food intake. A small margin exists between current exposure levels in the human population and the levels causing biological effects. Therefore, stringent control of concentrations of these contaminants in food and feed is needed. Eggs from free-range chicken are increasingly becoming an important part of the diet. These eggs have a higher risk of being contaminated with increased levels of dioxins and DL-PCB than barn or cage eggs. Ingestion of soil particles from environmentally contaminated areas may contribute to elevated dioxin levels in free-range chicken eggs. Available data show that current soil levels of dioxins and DL-PCB in residential and agricultural areas in Europe often appear to be too high to produce free-range eggs with dioxin levels below the current limit values in the EU. On the other hand, polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans concentrations in eggs from free-range chicken are not necessarily above the limit values. Contamination levels in soil should be kept low and should be controlled in areas with free foraging chicken although all modifying factors that influence uptake of dioxins and PCB from the environment and transfer into eggs are yet not well understood. 相似文献
69.
Solution Structure and Constrained Molecular Dynamics Study of Vitamin B12 Conjugates of the Anorectic Peptide PYY(3–36)
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Dr. Kelly E. Henry Dr. Deborah J. Kerwood Dr. Damian G. Allis Jayme L. Workinger Ron L. Bonaccorso Prof. George G. Holz Prof. Christian L. Roth Prof. Jon Zubieta Prof. Robert P. Doyle 《ChemMedChem》2016,11(9):1015-1021
Vitamin B12–peptide conjugates have considerable therapeutic potential through improved pharmacokinetic and/or pharmacodynamic properties imparted on the peptide upon covalent attachment to vitamin B12 (B12). There remains a lack of structural studies investigating the effects of B12 conjugation on peptide secondary structure. Determining the solution structure of a B12–peptide conjugate or conjugates and measuring functions of the conjugate(s) at the target peptide receptor may offer considerable insight concerning the future design of fully optimized conjugates. This methodology is especially useful in tandem with constrained molecular dynamics (MD) studies, such that predictions may be made about conjugates not yet synthesized. Focusing on two B12 conjugates of the anorectic peptide PYY(3–36), one of which was previously demonstrated to have improved food intake reduction compared with PYY(3–36), we performed NMR structural analyses and used the information to conduct MD simulations. The study provides rare structural insight into vitamin B12 conjugates and validates the fact that B12 can be conjugated to a peptide without markedly affecting peptide secondary structure. 相似文献
70.
Assessing the value of information of data‐centric activities in the chemical processing industry 4.0
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The quality of information generated in data‐driven empirical studies is of central importance in Industry 4.0. However, despite the undeniable and widely accepted importance, not sufficient attention has been devoted to its rigorous assessment and analysis. Consequently, if information quality cannot be measured, it also cannot be improved, and therefore current efforts for extracting value from big data empirical studies and data collectors are exposed to the risk of generating limited findings and insights, leading to suboptimal solutions. In this article, we describe and apply a framework for evaluating, analyzing and improving the quality of information generated in empirical studies called InfoQ, in the context of the Chemical Processing Industry (CPI). This systematic framework can be used by anyone involved in data‐driven activities, irrespectively of the context and specific goals. The application of InfoQ framework to several case studies is described in detail, to illustrate its practical relevance. © 2018 American Institute of Chemical Engineers AIChE J, 64: 3868–3881, 2018 相似文献