916 research outputs found
Worldwide cloud cover model
Classifying worldwide cloudiness into homogeneous regions, using a satellite data set containing day IR, night IR, incoming, and absorbed solar radiation measurements on a 2.5-degree latitude-longitude grid is considered. Methods of analysis are presented
Selection of High Performance Repair Materials for Pavements and Bridge Decks
The Ohio Transportation has identified the need to specify durable, more permanent high performing pavement and bridge deck patching materials. These materials need to allow for expedited pavement and bridge deck wearing surface repair for worker and user safety. Currently, either temporary or generally specified in-kind or like materials are being used to perform pavement patching. Usually, the Department provides generically specified cementitious or cold mix asphalt materials for patching wearing surfaces with varied performance characteristics. Current products used for these repairs are generally those that have been used for many decades for which competition exists. However, new or proprietary products are difficult to specify unless incorporated into a construction project for research purposes, an approved equal is permitted, or procurement of the product complies with the Department\u27s direct purchasing requirements. Consequently, this creates a situation where the desired product is precluded from use. The objective of this study was to specify durable, more permanent high performing pavement and bridge deck patching products that allow for expediting pavement and bridge deck wearing surface repair for worker and user safety. Aspects examined in this study include: history on causes of pavement patching failures, comparison of laboratory and field testing criteria from other organizations, product classifications based on material properties, analysis of available patching products, and identifying products to be tested based on previous research. The products chosen for the winter patching project were FlexSet and MG Krete. They have been placed in the field already and were chosen due to their excellent low temperature range, compliance of most ODOT and ASTM 928 laboratory standards and great previous field testing results from ERDC and NTPEP. The other four products recommended for summer placement are Delpatch, RepCon 928, SR-2000 and Optimix. They displayed characteristic
Selection of High Performance Repair Materials for Pavements and Bridge Decks
The Ohio Transportation has identified the need to specify durable, more permanent high performing pavement and bridge deck patching materials. These materials need to allow for expedited pavement and bridge deck wearing surface repair for worker and user safety. Currently, either temporary or generally specified in-kind or like materials are being used to perform pavement patching. Usually, the Department provides generically specified cementitious or cold mix asphalt materials for patching wearing surfaces with varied performance characteristics. Current products used for these repairs are generally those that have been used for many decades for which competition exists. However, new or proprietary products are difficult to specify unless incorporated into a construction project for research purposes, an approved equal is permitted, or procurement of the product complies with the Department\u27s direct purchasing requirements. Consequently, this creates a situation where the desired product is precluded from use. The objective of this study was to specify durable, more permanent high performing pavement and bridge deck patching products that allow for expediting pavement and bridge deck wearing surface repair for worker and user safety. Aspects examined in this study include: history on causes of pavement patching failures, comparison of laboratory and field testing criteria from other organizations, product classifications based on material properties, analysis of available patching products, and identifying products to be tested based on previous research. The products chosen for the winter patching project were FlexSet and MG Krete. They have been placed in the field already and were chosen due to their excellent low temperature range, compliance of most ODOT and ASTM 928 laboratory standards and great previous field testing results from ERDC and NTPEP. The other four products recommended for summer placement are Delpatch, RepCon 928, SR-2000 and Optimix. They displayed characteristic
Selection of High Performance Repair Materials for Pavements and Bridge Decks
The Ohio Transportation has identified the need to specify durable, more permanent high performing pavement and bridge deck patching materials. These materials need to allow for expedited pavement and bridge deck wearing surface repair for worker and user safety. Currently, either temporary or generally specified in-kind or like materials are being used to perform pavement patching. Usually, the Department provides generically specified cementitious or cold mix asphalt materials for patching wearing surfaces with varied performance characteristics. Current products used for these repairs are generally those that have been used for many decades for which competition exists. However, new or proprietary products are difficult to specify unless incorporated into a construction project for research purposes, an approved equal is permitted, or procurement of the product complies with the Department\u27s direct purchasing requirements. Consequently, this creates a situation where the desired product is precluded from use. The objective of this study was to specify durable, more permanent high performing pavement and bridge deck patching products that allow for expediting pavement and bridge deck wearing surface repair for worker and user safety. Aspects examined in this study include: history on causes of pavement patching failures, comparison of laboratory and field testing criteria from other organizations, product classifications based on material properties, analysis of available patching products, and identifying products to be tested based on previous research. The products chosen for the winter patching project were FlexSet and MG Krete. They have been placed in the field already and were chosen due to their excellent low temperature range, compliance of most ODOT and ASTM 928 laboratory standards and great previous field testing results from ERDC and NTPEP. The other four products recommended for summer placement are Delpatch, RepCon 928, SR-2000 and Optimix. They displayed characteristic
An overview of zeolites synthesised from coal fly ash and their potential for extracting heavy metals from industrial wastewater
Zeolites are aluminosilicate minerals widely used in industrial applications including as commercial adsorbents and catalysts. This overview focuses on zeolites synthesised from coal fly ash (CFA). Human activities and industrial developments generate large volumes of polluted water, which have a significant ecological impact. Industrial wastewater may consist of different pollutant types, but of specific interest to this work are heavy metals, which. Heavy metal ions are among the most dangerous pollutants due to their toxicity and carcinogenicity. This overview covers the recent scientific literature, focused on using CFA-derived zeolites to remove Ni, Hg, Mn, Cu, Zn, Cd, Pb, Cr, Co both from synthetic solutions replicating industrial wastewater and actual wastewater streams. The results described in many papers cited in this review look promising for industrial wastewater treatment operations. Furthermore, the large variety of possible synthetic zeolites provides a route for energy-efficient, pollutant-specific remediation of industrial heavy metals
Pathology of Piscinoodinium sp. (Protozoa: Dinoflagellida), parasites of the ornamental freshwater catfishes Corydoras spp. and Brochis splendens (Pisces: Callichthyidae)
Piscinoodinium sp. (Protozoa, Dinoflagellida) was commonly found on routine smears of samples of Brochis splendens and Corydoras spp. imported into Britain from South America, and on samples of the same group of fish examined at the exporters' holding facilities in Brazil. Infected fish had trophonts of different sizes on the gills and skin. In histological sections of the skin, the trophonts were found to be attached within depressions of different depths or enclosed by hyperplastic epithelial cells. Such enclosed trophonts have not previously been reported. Since some of the enclosed trophonts were dead, it was thought that enclosure was a result of the deep penetration of the trophont and the host defence mechanism. On the gills the Piscinoodinium infection was commonly associated with epithelial hypertrophy, focal and diffuse hyperplasia, oedema of the respiratory epithelium and lamellar fusion. The presence of this protozoan on different species of fish from the same shipment suggests that the infection was acquired before export. The source of infection and the stages of the export process which expose the fish to the highest risk of infection are discussed
Responsibility modelling for civil emergency planning
This paper presents a new approach to analysing and understanding civil emergency planning based on the notion of responsibility modelling combined with HAZOPS-style analysis of information requirements. Our goal is to represent complex contingency plans so that they can be more readily understood, so that inconsistencies can be highlighted and vulnerabilities discovered. In this paper, we outline the framework for contingency planning in the United Kingdom and introduce the notion of responsibility models as a means of representing the key features of contingency plans. Using a case study of a flooding emergency, we illustrate our approach to responsibility modelling and suggest how it adds value to current textual contingency plans
Disassembly of Li Ion cells—characterization and safety considerations of a recycling scheme
It is predicted there will be a rapid increase in the number of lithium ion batteries reaching end of life. However, recently only 5% of lithium ion batteries (LIBs) were recycled in the European Union. This paper explores why and how this can be improved by controlled dismantling, characterization and recycling. Currently, the favored disposal route for batteries is shredding of complete systems and then separation of individual fractions. This can be effective for the partial recovery of some materials, producing impure, mixed or contaminated waste streams. For an effective circular economy it would be beneficial to produce greater purity waste streams and be able to re-use (as well as recycle) some components; thus, a dismantling system could have advantages over shredding. This paper presents an alternative complete system disassembly process route for lithium ion batteries and examines the various processes required to enable material or component recovery. A schematic is presented of the entire process for all material components along with a materials recovery assay. Health and safety considerations and options for each stage of the process are also reported. This is with an aim of encouraging future battery dismantling operations
Deforming the Maxwell-Sim Algebra
The Maxwell alegbra is a non-central extension of the Poincar\'e algebra, in
which the momentum generators no longer commute, but satisfy
. The charges commute with the momenta,
and transform tensorially under the action of the angular momentum generators.
If one constructs an action for a massive particle, invariant under these
symmetries, one finds that it satisfies the equations of motion of a charged
particle interacting with a constant electromagnetic field via the Lorentz
force. In this paper, we explore the analogous constructions where one starts
instead with the ISim subalgebra of Poincar\'e, this being the symmetry algebra
of Very Special Relativity. It admits an analogous non-central extension, and
we find that a particle action invariant under this Maxwell-Sim algebra again
describes a particle subject to the ordinary Lorentz force. One can also deform
the ISim algebra to DISim, where is a non-trivial dimensionless
parameter. We find that the motion described by an action invariant under the
corresponding Maxwell-DISim algebra is that of a particle interacting via a
Finslerian modification of the Lorentz force.Comment: Appendix on Lifshitz and Schrodinger algebras adde
Mathematics for the exploration of requirements
The exploration of requirements is as complex as it is important in ensuring a successful software production and software life cycle. Increasingly, tool-support is available for aiding such explorations. We use a toy example and a case study of modelling and analysing some requirements of the global assembly cache of .NET to illustrate the opportunities and challenges that mathematically founded exploration of requirements brings to the computer science and software engineering curricula
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