Matrix computer analysis of curvilinear grid systems

A general equilibrium-stiffness method of matrix structural analysis was adapted and applied to the solution of the member end forces and moments of each of the members in a curvilinear structural grid system. A structural system of this nature is commonly used as the supporting framework for a steel-framed dome , in addition to being a basic structural component in many aerospace applications. An integral part of the development of the analysis was the development of a computer program to perform the many complex operations required to obtain the solution. The engineer, by supplying the appropriate structural data and load data to the computer program, is able to obtain the forces and moments at the ends of each of the members in the structural system corresponding to the six possible degrees of freedom of each one of the joints, or nodal points as they are referred to --Abstract, page ii

Direct liquefaction of coal with coal-derived solvents to produce precursors for carbon products

Direct liquefaction (hydrogenation) of coal has frequently been pursued as one avenue for the production of value added products from coal. The focus of this research was to evaluate five coal-derived liquids as substitutes for tetralin in the coal hydrogenation process. A mid-distillate by-product liquid from the production of high quality char was obtained from Antaeus Technical Services, Inc. and split into three fractions, the original liquid (RACL), its heavy fraction (DACL-H), and its light fraction (DACL-L). The other two liquids were heavy creosote oil (HCO) and carbon black base #1 (CBB) from Koppers Industries, Inc. These liquids were used as hydrogenation solvents under varying reaction conditions such as gas pressure, gas composition, and solvent-to-coal ratio. The products were separated by filtration and vacuum distillation to produce three fractions, the THF insolubles, pitch, and recycle solvent. The coal-alone conversions were calculated for each hydrogenation reaction and the pitch fractions were characterized as possible carbon-product precursors by softening point, ash content, coke yield, elemental analysis, and optical texture. (Abstract shortened by UMI.)

An experimental investigation into the electromagnetic compatibility aspects of high frequency power line communications

Power line communications technology, long established for low data rate applications, is now charting new territory with respect to data rates and provided services. This can only be achieved by increasing PLC operating frequencies from the low frequency band (below 148.5 kHz) to the high frequency band (1 MHz and upwards). There is now only one technical barrier to widespread deployment - Electromagnetic Compatibility. Existing low voltage power networks are optimised for the safe supply of electrical energy. Low voltage cables are often pseudo co-axial in their cross section, but when high frequency signals are coupled onto the network, part of the signal will be radiated. There is therefore a potential for interference to be caused to legitimate users of the radio spectrum. This thesis, and the experimental program underlying it, seeks to quantify potential problems and to propose mechanisms by which they could be mitigated to the extent that wide scale deployment of PLC networks becomes possible. The first part of the thesis offers a detailed introduction to the topics of electricity supply networks, power line communications, modulation techniques and electromagnetic compatibility. Existing EMC standards are examined and although some do not directly cover power line communications networks, key principals are drawn for later use in standards development. The thesis then seeks to examine the mechanisms by which high frequency interference might be caused. Radio propagation modes are discussed and a clear technical distinction is drawn between localised interference from a single PLC network to an individual radio user, and cumulative interference from wide spread deployment of PLC systems. Both such scenarios are examined in detail. The experimental program IS described quantifying radiated signal strength regression from a number of power networks and at a number of operating frequencies within the high frequency band. In this context, signal strength regression is the rate at which electrical field strength reduces with increasing measurement distance. The experimental setup uses a conventional signal generator to supply single test frequencies of known power spectral density, which are coupled onto a power network. The subsequent radiated signal is received via a conventional antenna and radio receiver at a number of locations surrounding the power network at known distances, and signal regression is derived. The experiment was repeated for a number of different frequencies and at representative urban, suburban and rural locations. Indeed, the experimental technique was evolved over a number of months to allow increased portability of the signal receiving equipment, and hence the number of measurements that could be taken. From the experimental results, presented both In tabular and graphical format, a number of conclusions can be drawn. Firstly, based on these results, antenna factors in the order of 85 dB/m can be expected of power line communication networks. It can be concluded that the field strength regression to be anticipated from PLC networks is likely to be significantly below the -20 dB per decade 'free space' regression figure that has often been used in interference models. In fact a regression figure of -35 dB/decade IS more representative of ground wave propagated interference from PLC networks. It is also possible to conclude that the adoption of orthogonal frequency division multiplexing as a multi-carrier spectral technique offers specific advantages in EMC terms. Due to its nature, it is possible to apply a frequency 'mask' to an OFDM based PLC system. Such a mask might be static, applied on a national or regional basis in order to guarantee non-interference with specific frequencies, for example those used for emergency radio channels. It would also be possible to add a dynamic frequency mask, controllable on each PLC system, to mitigate interference with radio services operating within the PLC operating band

The credibility of monetary policy: a survey of the literature with some simple applications to Caanda

We don't have an abstract yet, sorry. But I think the title is pretty descriptive.monetary policy, credibility, dynamic inconsistency, inflation

PonyGE2: Grammatical Evolution in Python

Grammatical Evolution (GE) is a population-based evolutionary algorithm, where a formal grammar is used in the genotype to phenotype mapping process. PonyGE2 is an open source implementation of GE in Python, developed at UCD's Natural Computing Research and Applications group. It is intended as an advertisement and a starting-point for those new to GE, a reference for students and researchers, a rapid-prototyping medium for our own experiments, and a Python workout. As well as providing the characteristic genotype to phenotype mapping of GE, a search algorithm engine is also provided. A number of sample problems and tutorials on how to use and adapt PonyGE2 have been developed.Comment: 8 pages, 4 figures, submitted to the 2017 GECCO Workshop on Evolutionary Computation Software Systems (EvoSoft

Examining Indonesian Terror Tactics: Characterizing Attacks on Indonesian Police

Strategies of Indonesian jihadist groups have undergone significant change over the last five years, away from high-cost, planned, and lethal bomb attacks on symbolic foreign targets such as embassies, hotels, and tourist destinations, in favor of domestic targets, notably assassinations of Indonesian police officers. In the past five years, over twenty police officers have been killed in attacks believed to be linked to jihadist groups. This paper explores issues relating to this shift, and whether the assassinations ought to be regarded as “terrorist” in nature This, in turn, raises the question of whether those responsible ought to be prosecuted for terrorism or for other crimes under Indonesia’s Criminal Code. The paper examines the relevant provisions of Indonesia’s anti-terrorism legislation and international law and suggests that, arguably, where an attack fails to cause terror as a matter of fact, logically and legally, it ought not be regarded as terrorism. However, in the wider context of striving to overturn the Indonesian government and establish an Islamic state, violent actions connected to Indonesian and international terrorist cells ought to be regarded as terrorist crimes. Ultimately, the question needs to be considered and settled by a higher Indonesian court, such as the Supreme Court or the Constitutional Court

Readability and Suitability of COPD Consumer Information

Copyright © 2017 Kathryn Fullmann et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Peer ReviewedBackground. Information leaflets have been shown to positively or negatively impact adherence, depending on their content. The objective of this study was to perform an appraisal of the consumer information provided in COPD inhaler monographs. Methods. COPD inhalers were identified from the Health Canada Drug Product Database. Medication information and instructions for inhaler use were analyzed for readability by seven formulas, with an acceptability threshold of grades 6–8. Three researchers rated suitability using a modified Suitability Assessment of Materials (SAM) tool and assessed leaflets for explicit warnings. Results. Twenty-six inhalers with a COPD indication were evaluated. Medication information sections were rated as “difficult to read” or “hard,” and 85% (22/26) had a reading level above grade 8. The instructions for inhaler use were rated as “easy” or “fairly easy” to read and 63% (16/26) met the threshold by all formulas. While all leaflets achieved superior suitability ratings, extreme warnings included risk of premature death (), risks of serious injury (), serious interactions (), and statements that convey a serious consequence to therapy (). Conclusion. While COPD information leaflets in Canada performed well in terms of readability and suitability, overemphasis on side effects, warnings, and precautions may contribute to patient fear and nonadherence

How to model mutually exclusive events based on independent causal pathways in Bayesian network models

This is supported by ERC project ERC-2013-AdG339182-BAYES_KNOWLEDGE

Assessment of Prescribed Burning Effects in Paludified Black Spruce Forests in Ontario’s Clay Belt Region

Paludification, the accumulation of poorly decomposed organic matter principally originating from Sphagnum, transforms black spruce forests to forested peatlands in the prolonged absence of fire. High-severity wildfires reverse this process by burning the organic matter layer and thus restart forest succession; in contrast low severity wildfires remove only the tree layer and do not reduce paludification. On the Ontario Clay Belt, a physiogeographic region prone to paludification due to its cold climate and poor drainage, current forest harvest practices (Careful Logging Around Advanced Growth; CLAAG) mimic low severity fires by removing trees but lacking forest floor and soil disturbances caused by fire. Historically, prescribed burning after clear cut (PB) was used as a site preparation technique, and may also be used for controlling paludification as it burns part of the organic soil layer and enhances soil fertility by releasing nutrients. Our retrospective study examines three hypotheses; compared to CLAAG and clear cut, 1) PB has positive effects on soil conditions, 2) controls sphagnum colonisation and 3) results in better growth of black spruce. We sampled 24 sites, using ecological forest classification and harvest records to ensure site equivalency. Results show a significant positive effect of PB on soil decomposition, nutrient contents and pH values. PB reduces Sphagnum establishment and growth. PB significantly increases black spruce growth (terminal shoots), however no difference in mean tree height is observed among treatments. We put forth that these contradictory results could be explained by a time lag in natural regeneration after PB as suggested by forest vertical structure. While not a high severity fire, prescribed burning after clear cut in paludified stands on the Ontario Clay Belt emulates some of its effects. Therefore we conclude that unlike CLAAG, prescribed burning after clear cut facilitates the development of unpaludified stands in a managed landscape