1,704 research outputs found
Semiclassical theory of spectral line shapes. II. Applications to CO, HCl, and OCS, broadened by inert gases
The semiclassical theory of spectral line broadening developed in the previous paper of this series is used to calculate the halfâwidths and shifts of nonoverlapping rotational spectral lines of CO, HCl, and OCS, broadened by inert gases. Comparisons are made with the available experimental data and with related theoretical analyses, and reasonable agreement is obtained. The method used applies both to fairly quantum systems as well as to the relatively classical ones. A symmetrized semiclassical expression for Wigner 6âj symbols is given and applied
Examining the quality and management of non-geometric building information modelling data at project hand-over
Through the exponential global increase of Building Information Modelling (BIM) adoption across the Construction industry, and the emergence of inter-connected, strategic and data-rich solutions; such as Big Data, the Internet of Things and Smart Cities, the importance associated with activities and decisions reliant on exact data input, transaction, analysis, and resulting actions becomes exponentially magnified. The supply of inaccurate BIM data may negatively impact on systems and processes that require fully assured data of appropriate quality/veracity, to support informed decision making, deliver functionality, facilitate services, or direct strategic actions within the built environment. This preliminary research intends to provide a catalyst for discussion, analysis and information retrieval relating to Building Information Modelling (BIM) processes where non-geometric data errors may; or are predicted to occur within a project environment. This may result in the delivery of data that cannot be described as representing truth or of good quality, and therefore of little value or use to the data user. The wider aspects of this research investigates specifically non-geometric data veracity & associated dimensions of data quality; in order to discover and explore future solutions to resolve current industry data quality assessment challenges. This paper provides feedback from the research focusing on the current state, presenting existing industry challenges and proposes further research areas based on initial findings
Routine characterization and interpretation of complex alkali feldspar intergrowths
Almost all alkali feldspar crystals contain a rich inventory of exsolution, twin, and domain microtextures that form subsequent to crystal growth and provide a record of the thermal history of the crystal and often of its involvement in replacement reactions, sometimes multiple. Microtextures strongly influence the subsequent behavior of feldspars at low temperatures during diagenesis and weathering. They are central to the retention or exchange of trace elements and of radiogenic and stable isotopes. This review is aimed at petrologists and geochemists who wish to use alkali feldspar microtextures to solve geological problems or who need to understand how microtextures influence a particular process. We suggest a systematic approach that employs methods available in most well founded laboratories. The crystallographic relationships of complex feldspar intergrowths were established by the 1970s, mainly using single-crystal X-ray diffraction, but such methods give limited information on the spatial relationships of the different elements of the microtexture, or of the mode and chronology of their formation, which require the use of microscopy. We suggest a combination of techniques with a range of spatial resolution and strongly recommend the use of orientated sections. Sections cut parallel to the perfect (001) and (010) cleavages are the easiest to locate and most informative. Techniques described are light microscopy; scanning electron microscopy using both backscattered and secondary electrons, including the use of surfaces etched in the laboratory; electron-probe microanalysis and analysis by energy-dispersive spectrometry in a scanning electron microscope; transmission electron microscopy. We discuss the use of cathodoluminescence as an auxiliary technique, but do not recommend electron-backscattered diffraction for feldspar work. We review recent publications that provide examples of the need for great care and attention to pre-existing work in microtextural studies, and suggest several topics for future work
Boron nanobelts grown under intensive ion bombardment
High-quality α-tetragonal crystalline boronnanobelts with [001] growth axis were synthesized using a novel method combining e-beam evaporation and plasma ion bombardment techniques. Intensive ion bombardment of the growingboronnanobelts at a high substrate temperature (âŒ1200°C) was found to be effective in increasing the atomic density, reducing the crystal disorder, and improving the yield of the nanobelts.This work was supported by the Australian Research
Council ARC
Semiclassical theory of spectral line shapes. II. Applications to CO, HCl, and OCS, broadened by inert gases
TAX REFORM AND INCOME DISTRIBUTION IN THE MEDIUM TERM. ESRI Working Paper No. 11, October 1989
This paper considers how future macro-economic developments in the Irish economy and
elsewhere are likely to affect the distribution of income and the tax system. In particular it
examines how 1992 and related developments will affect the scope for using the tax system to
change the distribution of income. In addition, using the ESRI's macro-economic model it
explores the extent to which policy on income distribution is likely to be constrained by the
existing structure of the economy
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Gonzalo de Berceo in Spanish Literary Criticism before 1780
In Spanish literature the first poet whose name we know with certainty is Gonzalo de Berceo, who flourished in the first half of the thirteenth century. The first complete edition of his works did not appear until toward the end of the eighteenth century. What happened to them and what was thought of them during the five centuries that intervened between the death of the poet and the year 1780, when the learned Librarian of the King, Don TomĂĄs Antonio SĂĄnchez, published the second volume of his CollecciĂłn de PoesĂas Castellanas Anteriores al Siglo XV giving it the subtitle of PoesĂas de Don Gonzalo de Berceo?
The question is not without interest; neither are the results of the investigations that lead us toward the possibility of answering it. Consequently, I propose setting forth with the utmost brevity the results that I have so far been able to obtain from my investigations. In citing the texts that speak of Berceo, I shall not stop to comment on them, nor even to correct the errorsâsometimes rather serious-they may contain
Micromechanics of sea urchin spines
The endoskeletal structure of the Sea Urchin, Centrostephanus rodgersii, has numerous long spines whose known functions include locomotion, sensing, and protection against predators. These spines have a remarkable internal microstructure and are made of single-crystal calcite. A finite-element model of the spine's unique porous structure, based on micro-computed tomography (microCT) and incorporating anisotropic material properties, was developed to study its response to mechanical loading. Simulations show that high stress concentrations occur at certain points in the spine's architecture; brittle cracking would likely initiate in these regions. These analyses demonstrate that the organization of single-crystal calcite in the unique, intricate morphology of the sea urchin spine results in a strong, stiff and lightweight structure that enhances its strength despite the brittleness of its constituent material
General Samora Yenus: Profile, Sudanese award, Expert comment
Unless otherwise indicated, all text posts are original productions of HornAffairs. If you copy and re-publish this post, you shall include a link to this page as well as a clear reference to HornAffairs and to the author.Sudanese President Al-Bashir honoured General Samora Yenus, the Chief of Staff of the Ethiopian National Defence Forces (ENDF), with the highest military medal, the Order of the two Niles. The former rebel commander, Samora, has been in charge of the armyâs military commitment in the region and the continent for a decade and a half. According to the UKâs Professor Ann Fitz-Gerald, the Sudanese military medal award âhas significance for Sudan, Ethiopia and the wider Horn of Africa regionâ
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