Impact of the River Maine Drainage Scheme on Hydro-Power Generation

A comparison is made between pre- and post-drainage scheme river flows recorded on the River Maine, Co. Antrim. A method of using five-year reference periods has been applied to the mean daily flows to smooth and eliminate, as far as possible, variations due to climatic changes.
Any loss of energy production which might have been due to changes in river flow was examined for turbine installations at a factory at Cullybackey. The quantities of usable water, and hence potential energy production, were calculated for each of the post-scheme five-year periods and compared with a pre-scheme five-year reference period. Any potential loss was then represented by a depreciation factor. It was found that no measurable loss of potential energy production has occurred on the River Maine in the post-scheme period.     

Evacuation of a Metro Train in an Underground Rail Transportation System: Flow Rate Capacity of Train Exits,Tunnel Walking Speeds and Exit Choice

Including in total 135 participants in the ages 19–69 years (recruited from the general public), an unannounced full-scale field evacuation experiment was performed in the Stockholm underground metro system on the night between October 17 and 18, 2014. The purpose was to collect data on the flow rate of people in train exits during the evacuation of a train in a tunnel and on the walking speed of people when moving long distances on an uneven surface in a tunnel, and to study exit choice and behaviour during an evacuation. Consequently, the experiment involved the evacuation of a rail car (a Bombardier C20 train) in a tunnel as well as the subsequent evacuation of the tunnel itself; the latter meant that the participants either could evacuate to the closest station (~400 m) or to an available emergency exit (~200 m). Among other things, the experiment demonstrated that the averaged flow rates of people in the train exits varied between 0.19 p/s and 0.22 p/s (0.14–0.16 p/m s when considering the train exit width of 1.4 m) and that the averaged walking speeds in the tunnel varied between 1.1 m/s and 1.2 m/s (no smoke present). Furthermore, all 135 participants found and used the available emergency exit, which had been equipped with a technical system consisting of a loudspeaker that broadcasted a combined alarm signal and a pre-recorded voice message.     

Time-dependent reliability of ageing structures: an approximate approach

Concrete structures may deteriorate over time due to aggressive service environments, leading to a reduction in their strengths, stiffnesses and reliabilities. In general, the assessment of time-dependent reliability of ageing structures must consider uncertainties in structural deterioration as well as non-stationarities in the structural load processes. This paper develops an approximate method for assessing the impact of structural deterioration and non-stationary live loads on structures, which requires only low-dimensional integration and reduces the cost of assessing time-dependent reliability over a service life extending to 50 years significantly. This approximate method is demonstrated through several examples. The importance of non-stationarities in the resistance and load processes on time-dependent reliability is illustrated and the accuracy of the method is confirmed in several cases utilising Monte Carlo simulation.     

Mathematical simulations of the electromagnetic system of a subminiature magnetoelectric engine

This paper is devoted to simulations of a valve electric engine with excitation from high-energy permanent rare-earth magnets. A feature of the design of the engine under consideration is that a stator is manufactured using the polycapillary glass-fiber technique. The conductors of the distributed stator winding are placed in holes pm the tube wall. The cylindrical bipolar rotor is made of iron–neodymium–boron. The assumption accepted in the work during the solving the Laplace equation has made it possible to obtain analytical solutions for the magnetic flux, emf, current, electromagnetic torque, and electromagnetic power.     

Distribution of mineral species in different coal seams of Talcher coalfield and its transformation behavior at varying temperatures

International Journal of Coal Science & Technology - Mineral phase characterization and thorough understanding of its transformation behavior during combustion are imperative to know the...     

Column Kinetic Tests Assessing Geochemical Behavior of Mine Wastes in the Jerada Coal District (Morocco)

The Jerada anthracite mine in Morocco was abandoned in 2001 after producing approximately 20 million tonnes of solid waste. The acid generating potential of these wastes was determined by performing tests on five samples collected from relatively older and more recent waste deposits. No carbonate minerals were identified. Pyrite was the only sulphide mineral observed and much of it had been completely transformed into Fe-oxides. Analysis of the waste indicated low levels (<1 %) of Ca and Mg, while Fe and Al concentrations generally exceeded 5 %. Modified Sobek static tests and column kinetic tests were conducted for 24 months. The static test results were not conclusive (20 <net neutralising potential <20 Kg CaCO₃/t). Leachates from the kinetic tests for three of the five samples showed an initially acidic pH, while those of the remaining two became acidic by the end of the tests. Sulfate concentrations (SO₄ ^2?) decreased over time from 5000 to 200 mg/L.     

Prediction of seepage water pressure for slope stability at the Gol-E-Gohar open pit mine

Slope stability accidents are one of the leading causes of destruction at open pit mining operations. Such interception of the seepage water results in the water inflow from the surrounding aquifer towards the mine excavations. In order to design an effective drainage scheme for an open pit mine, prediction of water inflow into the pit is essential. These changes have resulted in some failures and instability problems in different parts of Gol-E-Gohar iron open pit mine. It seems that main parameters which effect the failure and instability of the mine slopes are high pressure of groundwater and system of discontinuities (faults, joins, and bedding planes), which intersect the pit walls. The analysis results indicate that stability of the final pit slopes is sensitive to multi-planar failures and confined water in the walls pit is also a factor adversely affecting the stability. Problems associated with groundwater at the site were also assessed with the analyses of piezometric level and groundwater inflow.     

The Effects of Annealing After Equal Channel Angular Extrusion (ECAE) on Mechanical and Magnetic Properties of 49Fe-49Co-2V Alloy

Metallurgical and Materials Transactions A - Equal channel angular extrusion (ECAE) of 49Fe-49Co-2V, also known as Hiperco® 50A or Permendur-2V, greatly improves the strength and ductility of...     

Microstructure-Based Estimation of Strength and Ductility Distributions for $$\alpha +\beta $$ Titanium Alloys

Titanium alloys are processed to develop a wide range of microstructure configurations and therefore material properties. While these properties are typically measured experimentally, a framework for property prediction could greatly enhance alloy design and manufacturing. Here a microstructure-sensitive framework is presented for the prediction of strength and ductility as well as estimates of the bounds in variability for these properties. The framework explicitly considers distributions of microstructure via new approaches for instantiation of structure in synthetic samples. The parametric evaluation strategy, including the finite element simulation package FEpX, is used to create and test virtual polycrystalline samples to evaluate the variability bounds of mechanical properties in Ti-6Al-4V. Critical parameters for the property evaluation framework are provided by measurements of single crystal properties and advanced characterization of microstructure and slip system strengths in 2D and 3D. Property distributions for yield strength and ductility are presented, along with the validation and verification steps undertaken. Comparisons between strain localization and slip activity in virtual samples and in experimental grain-scale strain measurements are also discussed.