scholarly journals Fluidized Bed Combustion and Gasification of Fossil and Renewable Slurry Fuels

Energies ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 7766
Author(s):  
Francesco Miccio ◽  
Federica Raganati ◽  
Paola Ammendola ◽  
Farouk Okasha ◽  
Michele Miccio
Keyword(s):  
Renewable Resources ◽  
State Of The Art ◽  
Optimal Choice ◽  
Fluidized Bed Combustion ◽  
Biomass Density ◽  
Hydrophilic Behavior ◽  
Recent Developments ◽  
Bed Materials ◽  
Civil Sector ◽  
Near Future

This article provides a comprehensive review of the state of the art and more recent developments of the thermochemical treatments of slurry fuels in fluidized beds (FB). The review focuses on FB combustion and gasification of slurry fuels based on coal, biomass, sludge, and wastes from industry, agriculture, and the civil sector. The investigations at research and industrial levels over the last decades are presented and discussed, highlighting the adopted technological solutions, the results in terms of feasibility and efficiency, and the perspectives of future development. The different behavior between bubbling and circulating beds was addressed, in particular the optimal choice depending on the process (combustion/gasification/pyrolysis) and fuel properties (e.g., water content). Fundamental studies on interactions between the slurry fuels and the hot bed materials are also reviewed. The cumulative trend of reviewed investigations over the last decades depicts the abandonment of coal-based mixtures used in large plants, and the growing interest in the use of biomass-based slurries for small size application. In this respect, the shift from coal to biomass opens new challenges because of the different properties of biomass (density, fibrous structure, spontaneous degradation, hydrophilic behavior, etc.). Biomass-based slurries circumvent problems posed by using solid dry biomass, particularly in handling, storing, and feeding. Although slurry fuels represent a narrow sector, the results of the research investigations and the experience gained with coal can be exploited to contribute to the achievement of a circular approach based on renewable resources in the near future.

scholarly journals State of the Art in Computational Bioacoustics and Machine Learning: How far have we come?

2019 ◽  
Vol 3 ◽  
Author(s):  
Dan Stowell
Keyword(s):  
Machine Learning ◽  
Big Data ◽  
Deep Learning ◽  
State Of The Art ◽  
Learning Networks ◽  
Recent Developments ◽  
Audio Data ◽  
Ecological Applications ◽  
Near Future ◽  
Statistical Ecology

Terrestrial bioacoustics, like many other domains, has recently witnessed some transformative results from the application of deep learning and big data (Stowell 2017, Mac Aodha et al. 2018, Fairbrass et al. 2018, Mercado III and Sturdy 2017). Generalising over specific projects, which bioacoustic tasks can we consider "solved"? What can we expect in the near future, and what remains hard to do? What does a bioacoustician need to understand about deep learning? This contribution will address these questions, giving the audience a concise summary of recent developments and ways forward. It builds on recent projects and evaluation campaigns led by the author (Stowell et al. 2015, Stowell et al. 2018), as well as broader developments in signal processing, machine learning and bioacoustic applications of these. We will discuss which type of deep learning networks are appropriate for audio data, how to address zoological/ecological applications which often have few available data, and issues in integrating deep learning predictions with existing workflows in statistical ecology.

Natural or artificial? A reflection on a complex ontology

2020 ◽  
pp. 147309522096335
Author(s):  
Simone Amato Cameli
Keyword(s):  
Critical Reflection ◽  
State Of The Art ◽  
Urban Environments ◽  
Social Structures ◽  
Planning Theory ◽  
Human Beings ◽  
Recent Developments ◽  
Future Risk ◽  
Natural Conception ◽  
Near Future

State-of-the-art planning theory considers cities as cyborg entities composed by a “natural” part (human beings and their social structures) and an “artificial” part (buildings, infrastructure and other urban artifacts). We contend that this hybrid conception is indissolubly coupled with the ability to discriminate perfectly between the “natural” and the “artificial”. But is this actually the case? We will provide a critical reflection on this ontological issue pointing out that current urban planning theory as well as the general philosophical reflection is not able to produce a rigorous, consistent epistemic criterion to draw this distinction. Long-standing difficulties in this respect are exponentially amplified by recent developments in artificial intelligence, nanotechnology and biotechnology, and their growing relevance in urban environments of the near future risk making the cyborg conception informing the complexity theory of cities obsolete. We will conclude our reflection identifying a possible path for overcoming this dualism toward a more socio-natural conception internalizing the proteiform character of the concept of “nature” itself as well as its inherent cognitive/political element.

scholarly journals Monomers and Macromolecular Materials from Renewable Resources: State of the Art and Perspectives

Molecules ◽  
2021 ◽  
Vol 27 (1) ◽  
pp. 159
Author(s):  
Alessandro Gandini ◽  
Talita M. Lacerda
Keyword(s):  
Environmental Impacts ◽  
Renewable Resources ◽  
Circular Economy ◽  
State Of The Art ◽  
Raw Materials ◽  
Biological Processes ◽  
Short Term ◽  
The World ◽  
Polymer Industry ◽  
Near Future

A progressively increasing concern about the environmental impacts of the whole polymer industry has boosted the design of less aggressive technologies that allow for the maximum use of carbon atoms, and reduced dependence on the fossil platform. Progresses related to the former approach are mostly based on the concept of the circular economy, which aims at a thorough use of raw materials, from production to disposal. The latter, however, has been considered a priority nowadays, as short-term biological processes can efficiently provide a myriad of chemicals for the polymer industry. Polymers from renewable resources are widely established in research and technology facilities from all over the world, and a broader consolidation of such materials is expected in a near future. Herein, an up-to-date overview of the most recent and relevant contributions dedicated to the production of monomers and polymers from biomass is presented. We provide some basic issues related to the preparation of polymers from renewable resources to discuss ongoing strategies that can be used to achieve original polymers and systems thereof.

Recent developments in automated Transmission Electron MI

1989 ◽  
Vol 47 ◽  
pp. 46-47
Author(s):  
W.J. de Ruijter ◽  
P. Rez ◽  
David J. Smith
Keyword(s):  
Image Analysis ◽  
Computer Image ◽  
Lens Design ◽  
Computer Image Analysis ◽  
Transmission Electron ◽  
Resolution Electron ◽  
Recent Developments ◽  
On Line ◽  
Routine Procedures ◽  
Near Future

There is growing interest in the on-line use of computers in high-resolution electron n which should reduce the demands on highly skilled operators and thereby extend the r of the technique. An on-line computer could obviously perform routine procedures hand, or else facilitate automation of various restoration, reconstruction and enhan These techniques are slow and cumbersome at present because of the need for cai micrographs and off-line processing. In low resolution microscopy (most biologic; primary incentive for automation and computer image analysis is to create a instrument, with standard programmed procedures. In HREM (materials researc computer image analysis should lead to better utilization of the microscope. Instru (improved lens design and higher accelerating voltages) have improved the interpretab the level of atomic dimensions (approximately 1.6 Å) and instrumental resolutior should become feasible in the near future.

Organic Reactivity Control by Means of Neighboring Groups and Organometallics. A Personal Account

1994 ◽  
Vol 59 (1) ◽  
pp. 1-74 ◽  
Author(s):  
Pavel Kočovský
Keyword(s):  
Transition Metals ◽  
Cyclopropane Ring ◽  
Allylic Substitutions ◽  
Recent Developments ◽  
Cardioactive Drug ◽  
Novel Method ◽  
Metal Catalyzed ◽  
Electrophilic Additions ◽  
Near Future ◽  
First Time

This review summarizes the main topics of our research and covers the period of the last 15 years. The prime interest is focused on various ways of controlling the regio- and stereoselectivity of selected organic reactions, in particular electrophilic additions, cleavage of cyclopropane rings, and allylic substitutions by means of neighboring groups and/or transition and non-transition metals. In the first part, the factors governing the course of electrophilic additions are assessed, culminating in the formulation of selection rules for the reactivity of cyclohexene systems, and in a concise synthesis of the natural cardioactive drug, strophanthidin. These studies also contribute to a better understanding of the mechanisms of electrophilic additions. The second part describes recent developments in the stereo- and regiocontrolled cleavage of cyclopropane rings by non-transition metals (Tl and Hg), and the reactivity and transmetalation (with Pd) of the primary products. This methodology has resulted in novel routes to unique polycyclic structures, and will have synthetic applications in the near future. Evidence for the stereospecific "corner" cleavage of the cyclopropane ring has been provided for the first time for Tl and later for Hg. The third part deals with transition metal-catalyzed allylic substitution. Evidence for a new "syn" mechanism for the formation of the intermediate (π-allyl)palladium complex has been provided, which runs counter to the generally accepted "anti" mechanism. A novel method for a Pd-catalyzed allylic oxidation has been developed and employed in the synthesis of natural sesquiterpenes. The increasing importance of transition and non-transition metals for synthetic organic chemistry is demonstrated by their unique reactivity in a number of the papers included in this review.

Milton in China ‘Yet Once More’

2017 ◽  
Author(s):  
Bing Yan
Keyword(s):  
Literary Criticism ◽  
World Literature ◽  
Paradise Lost ◽  
Subsequent Discussion ◽  
Recent Developments ◽  
Collaborative Context ◽  
Chinese Literary Criticism ◽  
Near Future

This chapter overviews Chinese reception of Milton, with an emphasis on some of the most well-known Chinese translations of Paradise Lost. Close readings of these translations against Milton’s original demonstrate the difficulties of and resolutions for rendering Milton’s verse specific to Chinese. The subsequent discussion of the paratexts accompanying Chinese translations and of ‘introduction to world literature’ series gives a sense of the collaborative context that has shaped and continues to shape today’s general reception of Milton in China. That politically charged reception, eager to view Milton’s Satan as the embodiment of the poet’s revolutionary spirit, also dominates some recent works of Chinese literary criticism. The chapter ends by conceding that, while Milton scholarship in China has been relatively univocal and is still young, recent developments in world literature promise that innovative and intriguing work on Milton can be expected from China in the near future.

scholarly journals A Survey on Bias and Fairness in Machine Learning

2021 ◽  
Vol 54 (6) ◽  
pp. 1-35
Author(s):  
Ninareh Mehrabi ◽  
Fred Morstatter ◽  
Nripsuta Saxena ◽  
Kristina Lerman ◽  
Aram Galstyan
Keyword(s):  
Artificial Intelligence ◽  
Machine Learning ◽  
Deep Learning ◽  
Real World ◽  
State Of The Art ◽  
Future Directions ◽  
Discriminatory Behavior ◽  
Real World Applications ◽  
Near Future ◽  
Different Sources

With the widespread use of artificial intelligence (AI) systems and applications in our everyday lives, accounting for fairness has gained significant importance in designing and engineering of such systems. AI systems can be used in many sensitive environments to make important and life-changing decisions; thus, it is crucial to ensure that these decisions do not reflect discriminatory behavior toward certain groups or populations. More recently some work has been developed in traditional machine learning and deep learning that address such challenges in different subdomains. With the commercialization of these systems, researchers are becoming more aware of the biases that these applications can contain and are attempting to address them. In this survey, we investigated different real-world applications that have shown biases in various ways, and we listed different sources of biases that can affect AI applications. We then created a taxonomy for fairness definitions that machine learning researchers have defined to avoid the existing bias in AI systems. In addition to that, we examined different domains and subdomains in AI showing what researchers have observed with regard to unfair outcomes in the state-of-the-art methods and ways they have tried to address them. There are still many future directions and solutions that can be taken to mitigate the problem of bias in AI systems. We are hoping that this survey will motivate researchers to tackle these issues in the near future by observing existing work in their respective fields.

scholarly journals Recent Developments in Coatings, Gratings, and Reflective Components

1984 ◽  
Vol 79 ◽  
pp. 607-616
Author(s):  
R. R. Shannon
Keyword(s):  
State Of The Art ◽  
New Technology ◽  
The State ◽  
Current Technology ◽  
Large Size ◽  
Incoming Radiation ◽  
Recent Developments ◽  
Electronic Sensors ◽  
Large Primary ◽  
Telescope System

The requirements on gratings and coatings for astronomical use differ from the general industrial requirements primarily in the scale of the components to be fabricated. Telescopes have large primary mirrors which require large coating plants to handle the components. Dispersive elements are driven by the requirement to be efficient in the presence of large working apertures, and usually optimize to large size in order to efficiently use the incoming radiation. Beyond this, there is a “new” technology of direct electronic sensors that places specific limits upon the image scale that can be used at the output of a telescope system, whether direct imagery or spectrally divided imagery is to be examined. This paper will examine the state of the art in these areas and suggest some actions and decisions that will be required in order to apply current technology to the predicted range of large new telescopes.

Rewiew of Fracture and Fatigue in Ceramic Matrix Composites

2000 ◽  
Vol 53 (6) ◽  
pp. 147-174 ◽  
Author(s):  
Victor Birman ◽  
Larry W. Byrd
Keyword(s):  
High Temperature ◽  
State Of The Art ◽  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
Review Article ◽  
Successful Implementation ◽  
Matrix Composites ◽  
Recent Developments ◽  
Hostile Environments

A review of recent developments and state-of-the-art in research and understanding of damage and fatigue of ceramic matrix composites is presented. Both laminated as well as woven configurations are considered. The work on the effects of high temperature on fracture and fatigue of ceramic matrix composites is emphasized, because these materials are usually designed to operate in hostile environments. Based on a detailed discussion of the mechanisms of failure, the problems that have to be addressed for a successful implementation of ceramic matrix composites in design and practical operational structures are outlined. This review article includes 317 references.

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