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This paper demonstrates how certain logic and combinatorial tasks can be solved using CNNs. A design method is proposed for solving combinatorial tasks on a CNN. It can be used to simulate cellular automata on a CNN, to prove the self-reproducing capability of the CNNUM and for sorting, histogram calculation, parity analysis and minimum Hamming distance computation. These solutions are especially useful since they can serve as subroutines of more complex CNNUM algorithms. As an important real-life application the lay-out of printed circuit boards is designed with the CNNUM at an extremely high speed.
To obviate the destructive interaction of highly reactive metallocene catalysts with classical silica-based supports while retaining the advantage of supported catalysts, a noninteracting polystyrene support was developed. Supported catalysts for the polymerization of α-olefins are prepared by treating lightly cross-linked, chloromethylated polystyrene beads consecutively with a secondary amine, an ammonium salt of a weakly coordinating anion, and a neutral dialkylmetallocene. Catalytic sites are distributed homogeneously throughout the support particle, and the polymerization occurs within the bead, in contrast to traditional surface-supported metallocene catalysts. The copolymerization of ethylene and 1-hexene at 40°C affords discrete spherical polyolefin beads with a size (0.3 to 1.4 millimeters) that varies according to the polymerization time.
Levels of literacy and the variance in them, continue to be a problem in the world. These problems are ubiquitous in the sense that they change form from developing to developed regions, but do not seize to exist. For example, while teacher absenteeism is a fairly large problem in the developing world, student motivation can pose challenges in the developed world. Prior research has demonstrated that games can serve as an efficient medium in bridging these literacy gaps, generating student motivation (or engagement) not just in short term but also in the long term. This dissertation is dedicated to the investigation and application of spoken language technology to language acquisition contexts in the developed world. We explore the broader research question in two major contexts. Firstly, lack of proper English pronunciations is a major problem for immigrant population in developed countries like U.S. This poses various problems, including a barrier to entry into mainstream society. Therefore, the first part of the dissertation involves exploration of speech technologies merged with activity-based and arcade-based games to do pronunciation feedback for Hispanic children. This also involves using linguistic theory to determine computational criteria for intelligibility in speech and computational adaptations to reflect them. We also present results from a 3-month long evaluation of this system. Secondly, a large body of research has shown that the literacy gap between children is well-established before formal schooling begins, and predicts academic performance throughout primary, middle and secondary school. Therefore, in the second part of the dissertation we explore natural interactions for preschoolers that would engage them in game-like activities that involve short follow-up conversations. We explore the design and implementation of a conversational agent called Spot, that acts as a question-answering companion for preschool children. We present a month long study with 20 preschoolers with some insight on the potential, efficiency and usage of such a system. We end with a discussion on computational complexities in building Spot, and rules that it uses to work around speech recognition and natural language understanding errors.
We propose the Breathing Earth System Simulator (BESS), an upscaling approach to quantify global gross primary productivity and evapotranspiration using MODIS with a spatial resolution of 1-5 km and a temporal resolution of 8 days. This effort is novel because it is the first system that harmonizes and utilizes MODIS Atmosphere and Land products on the same projection and spatial resolution over the global land. This enabled us to use the MODIS Atmosphere products to calculate atmospheric radiative transfer for visual and near infrared radiation wave bands. Then we coupled atmospheric and canopy radiative transfer processes, with models that computed leaf photosynthesis, stomatal conductance and transpiration on the sunlit and shaded portions of the vegetation and soil. At the annual time step, the mass and energy fluxes derived from BESS showed strong linear relations with measurements of solar irradiance (r(2) = 0.95, relative bias: 8%), gross primary productivity (r(2) = 0.86, relative bias: 5%) and evapotranspiration (r(2) = 0.86, relative bias: 15%) in data from 33 flux towers that cover seven plant functional types across arctic to tropical climatic zones. A sensitivity analysis revealed that the gross primary productivity and evapotranspiration computed in BESS were most sensitive to leaf area index and solar irradiance, respectively. We quantified the mean global terrestrial estimates of gross primary productivity and evapotranpiration between 2001 and 2003 as 118 +/- 26 PgC yr(-1) and 500 +/- 104 mm yr(-1) (equivalent to 63,000 +/- 13,100 km(3) yr(-1)), respectively. BESS-derived gross primary productivity and evapotranspiration estimates were consistent with the estimates from independent machine-learning, data-driven products, but the process-oriented structure has the advantage of diagnosing sensitivity of mechanisms. The process-based BESS is able to offer gridded biophysical variables everywhere from local to the total global land scales with an 8-day interval over multiple years.
ADVERTISEMENT RETURN TO ARTICLES ASAPEditorialNEXTChemical Sensors and Imaging: Molecular, Materials, and Biological PlatformsMarco S. Messina*Marco S. Messina*Email: [email protected]More by Marco S. Messinahttps://orcid.org/0000-0003-2827-118X and Christopher J. Chang*Christopher J. Chang*Email: [email protected]More by Christopher J. Changhttps://orcid.org/0000-0001-5732-9497Cite this: ACS Cent. Sci. 2023, XXXX, XXX, XXX-XXXPublication Date (Web):September 18, 2023Publication History Published online18 September 2023https://doi.org/10.1021/acscentsci.3c01070Copyright © 2022 The Authors. Published by American Chemical Society. This publication is licensed under CC-BY 4.0. License Summary*You are free to share (copy and redistribute) this article in any medium or format and to adapt (remix, transform, and build upon) the material for any purpose, even commercially within the parameters below:Creative Commons (CC): This is a Creative Commons license.Attribution (BY): Credit must be given to the creator.View full license*DisclaimerThis summary highlights only some of the key features and terms of the actual license. It is not a license and has no legal value. Carefully review the actual license before using these materials. This publication is Open Access under the license indicated. Learn MoreArticle Views-Altmetric-Citations-LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (881 KB) Get e-AlertscloseSUBJECTS:Biological imaging,Dyes and pigments,Peptides and proteins,Probes,Sensors Get e-Alerts
Communication in data-parallel applications often involves a collection of parallel flows. Traditional techniques to optimize flow-level metrics do not perform well in optimizing such collections, because the network is largely agnostic to application-level requirements. The recently proposed coflow abstraction bridges this gap and creates new opportunities for network scheduling. In this paper, we address inter-coflow scheduling for two different objectives: decreasing communication time of data-intensive jobs and guaranteeing predictable communication time. We introduce the concurrent open shop scheduling with coupled resources problem, analyze its complexity, and propose effective heuristics to optimize either objective. We present Varys, a system that enables data-intensive frameworks to use coflows and the proposed algorithms while maintaining high network utilization and guaranteeing starvation freedom. EC2 deployments and trace-driven simulations show that communication stages complete up to 3.16X faster on average and up to 2X more coflows meet their deadlines using Varys in comparison to per-flow mechanisms. Moreover, Varys outperforms non-preemptive coflow schedulers by more than 5X.
Previous research has associated the development of social phobia with parental rearing practices, learning influences such as conditioning, vicarious transmission and verbal acquisition, and the individual's own response to social situations. The present study aimed to further investigate these possible antecedents of social phobia. A Learning History Questionnaire (LHQ) was completed by patients with social phobia ( n =55), patients with posttraumatic stress disorder (PTSD; n =30), and non-patient controls ( n =30). The LHQ focused on events that occurred before the age of 14 (the median age of onset for social phobia). The results indicated the importance of parental rearing practices such as not actively encouraging participation in social situations and emotional coldness. Difficulties with peer group were highlighted as important contributors to conditioning experiences. Individual response factors, especially post-event rumination, are potentially associated with the development of social phobia. Four of the 12 significant variables were unique to the social phobia group when the results from the PTSD group were taken into account. Further research is required to clarify the extent to which the environmental factors assessed in this study specifically contribute to the development of social phobia or to the development of anxiety more generally.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Necessary and sufficient conditions are given for the uniqueness of solution of nonlinear resistive circuits made of strictly monotoneincreasing nonlinear resistors, dc sources, and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">k</tex> linear current-controlled current sources (CCCS's) or linear voltage-controlled voltage sources (VCVS's) whose controlling coefficients <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">{\alpha}_{\mu}</tex> are bounded by <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0<{\alpha}_{\mu}<{\alpha}_{\mu}max'{\mu} = 1,2,{\cdots}, k</tex> . These conditions are cast in explicit topological terms and are therefore easy to check.
The lithium salts of 1,2,3,4,5,6,7,8-octamethylfluorenyl (Flu′′) and 1,2,3,4,5,6,7,8,9-nonamethylfluorenyl (Flu*) were reacted with Zr and Hf half-sandwich complexes to generate mixed-ligand-metallocenes Cp′′Flu′′ZrCl2 (1), Cp′′Flu*ZrCl2 (2), and Cp*Flu*HfCl2 (3) (Cp′′ = 1,3-(SiMe3)2C5H3, Cp* = C5Me5). Reaction of the metallocene dichlorides with MeLi yielded the dimethyl derivatives Cp′′Flu*ZrMe2 (4) and Cp*Flu*HfMe2 (5). Reduction of the zirconocene dichlorides in the presence of CO gas yielded the dicarbonyl derivatives Cp′′Flu′′Zr(CO)2 (6) and Cp′′Flu*Zr(CO)2 (7), which represent the first examples of zirconocene dicarbonyls containing a fluorenyl ligand derivative. Structural characterization of the zirconocene dichloride 2 and the dicarbonyls 6 and 7 revealed that the methylated fluorenyl ligands adopt an η5-coordination and display a twisted tricyclic core in each case. A spectroscopic study of a small series of zirconocene dicarbonyl analogues indicates that the methylated fluorenyl ligands are strong electron donors and similar in this regard to heptamethylindenyl (Ind*) and Cp*.
