A geostatistical calculation of the Coal Mine Roof Rating

In this thesis, the need for an efficient and easy to use program which calculates a Coal Mine Roof Rating (CMRR) over a spatial area is established. In response to this need, a program which enables for the geostatistical calculation of the CMRR over a spatial area was developed as an engineering tool to quantify the geo-mechanical stability of the roof rock within the bolted horizon of a coal mine through the utilization of one of the more widely available geologic model data formats.;The CMRR program utilizes the popular AutoCAD/SurvCADD platform and grid data format as a foundation for inputting the geologic characteristics necessary to calculate a CMRR. Through this feature the user can generate areal CMRR stability information from drill holes, SurvCADD geology grids and/or underground observations. This areal CMRR input can then be individually plotted for interpretation or combined with other geologic, structural and stress-based factors in order to generate an overall stability factor for the mine.;Upon completion of the program, a case study was performed in order to identify any shortcomings or additional needs that had not been previously identified. The case study utilized both the areal CMRR calculation and the integration of the CMRR program with a previously developed stability mapping package to create a stability map for the mine. Agreement was found between the resultant stability map and the field observations.;In the conclusion of this thesis it appears that the CMRR program can and will serve as a useful tool for the mining engineer in the evaluation of coal measure roof rock over a large spatial area. Through its application, both the mine engineer and the mine personnel can benefit from the increased knowledge of the coal measure roof rock being studied and the increased safety which that brings

Technology and methods of making decorated balusters

Woodworking companies looking for a simple solution to simplify and speed up thewhole process of making a carved balusters. Tech solution is the replacement of threadedelements solid wood balusters on plastic threaded overhead items secured by adhesive to thesurface of the workpiece chiseled. This solution allows to reduce the cost of manufacturingcarved balusters, without resorting to a woodcarver and using expensive equipment. Throughfurther improvements, such as painting, patina, it turns out a product that is difficult todistinguish from solid carved balusters

Microstructured optical fibres for gas sensing: design fabrication and post-fab processing

Air/silica Microstructured Optical Fibers (MOFs) offer new prospects for fiber based sensor devices. In this paper, two topics of particular significance for gas sensing using air guiding Photonic Bandgap Fibers (PBGFs) are discussed. First, we address the issue of controlling the modal properties of PBGFs and demonstrate a single mode, polarization maintaining air guiding PBGF. Secondly, we present recent improvements of a femtosecond laser machining technique for fabricating fluidic channels in PBGFs, which allowed us to achieve cells with multiple side access channels and low additional loss

Medium-Energy Proton-Nucleus Elastic Scattering in the Impulse Approximation

This work was supported by National Science Foundation Grants PHY 76-84033A01, PHY 78-22774, and Indiana Universit

Citation gaming induced by bibliometric evaluation: A country-level comparative analysis

It is several years since national research evaluation systems around the globe started making use of quantitative indicators to measure the performance of researchers. Nevertheless, the effects on these systems on the behavior of the evaluated researchers are still largely unknown. For investigating this topic, we propose a new inwardness indicator able to gauge the degree of scientific self-referentiality of a country. Inwardness is defined as the proportion of citations coming from the country over the total number of citations gathered by the country. A comparative analysis of the trends for the G10 countries in the years 2000-2016 reveals a net increase of the Italian inwardness. Italy became, both globally and for a large majority of the research fields, the country with the highest inwardness and the lowest rate of international collaborations. The change in the Italian trend occurs in the years following the introduction in 2011 of national regulations in which key passages of professional careers are governed by bibliometric indicators. A most likely explanation of the peculiar Italian trend is a generalized strategic use of citations in the Italian scientific community, both in the form of strategic author self-citations and of citation clubs. We argue that the Italian case offers crucial insights on the constitutive effects of evaluation systems. As such, it could become a paradigmatic case in the debate about the use of indicators in science-policy contexts

Citation gaming induced by bibliometric evaluation: A country-level comparative analysis

It is several years since national research evaluation systems around the globe started making use of quantitative indicators to measure the performance of researchers. Nevertheless, the effects on these systems on the behavior of the evaluated researchers are still largely unknown. For investigating this topic, we propose a new inwardness indicator able to gauge the degree of scientific self-referentiality of a country. Inwardness is defined as the proportion of citations coming from the country over the total number of citations gathered by the country. A comparative analysis of the trends for the G10 countries in the years 2000-2016 reveals a net increase of the Italian inwardness. Italy became, both globally and for a large majority of the research fields, the country with the highest inwardness and the lowest rate of international collaborations. The change in the Italian trend occurs in the years following the introduction in 2011 of national regulations in which key passages of professional careers are governed by bibliometric indicators. A most likely explanation of the peculiar Italian trend is a generalized strategic use of citations in the Italian scientific community, both in the form of strategic author self-citations and of citation clubs. We argue that the Italian case offers crucial insights on the constitutive effects of evaluation systems. As such, it could become a paradigmatic case in the debate about the use of indicators in science-policy contexts. © 2019 Baccini et al

The influence of cold Jupiters in the formation of close-in planets. I. planetesimal transport

The formation of a cold Jupiter (CJ) is expected to quench the influx of pebbles and the migration of cores interior to its orbit, thus limiting the efficiency of rocky planet formation either by pebble accretion and/or orbital migration. Observations, however, show that the presence of outer CJs ( >1 au and >0.3 Jupiter masses) correlates with the presence of inner Super Earths (at <1 au). This observation may simply be a result of an enhanced initial reservoir of solids in the nebula required to form a CJ or a yet-to-be-determined mechanism assisted by the presence of the CJ. In this work, we focus on the latter alternative and study the orbital transport of planetesimals interior to a CJ subject to the gravity and drag from a viscously-evolving gaseous disk. We find that a secular resonance sweeping inwards through the disk gradually transports rings of planetesimals when their drag-assisted orbital decay is faster than the speed of the resonance scanning. This snowplow-like process leads to large concentration (boosted by a factor of ~10-100) of size-segregated planetesimal rings with aligned apsidal lines, making their expected collisions less destructive due to their reduced velocity dispersion. This process is efficient for a wide range of alpha-disk models and Jovian masses, peaking for ~1-5 Jupiter masses, typical of observed CJs in radial velocity surveys. Overall, our work highlights the major role that the disk's gravity may have on the orbital redistribution of planetesimals, depicting a novel avenue by which CJs may enhance the formation of inner planetary systems, including super-Earths and perhaps even warm and hot Jupiters.Comment: 18 pages, 11 figure

Digital image processing using parallel computing based on CUDA technology

This article describes expediency of using a graphics processing unit (GPU) in big data processing in the context of digital images processing. It provides a short description of a parallel computing technology and its usage in different areas, definition of the image noise and a brief overview of some noise removal algorithms. It also describes some basic requirements that should be met by certain noise removal algorithm in the projection to computer tomography. It provides comparison of the performance with and without using GPU as well as with different percentage of using CPU and GPU

Radiation from relativistic electrons in "light" and in conventional undulators. Classical and quantum approaches

A photon spectrum of undulator radiation (UR) is calculated in the semi-classical approach. The UR intensity spectrum is determined by an electron trajectory in the undulator neglecting by energy losses for radiation. Using the Planck's law, the UR photon spectrum can be calculated from the classical intensity spectrum both for linear and nonlinear regimes. The radiation of an electron in a field of strong electromagnetic wave (radiation in the "light" undulator) is considered in the quantum electromagnetic frame. Comparison of results obtained by both approaches has been shown that UR spectra in the whole cone coincide with high accuracy for the case x<<1. Characteristics of the collimated UR beam were simulated with taking into account the discrete process of photon emission along an electron trajectory in both kinds of undulators

Investigation of high-energy external influences on structural heredity of the Ti-Nb alloy

The effects of high-energy external influences on structural heredity of Ti-Nb alloy is investigated in this paper. By the methods of XRD, SEM, EDX and optical microscopy it was founded that thermal treatment and severe plastic deformation lead to the phase transformations in the alloy, the dendritic segregation occurs and retains in the alloy under external influences