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Closed-form analytical solutions for assessing the consequences of climate change on fresh groundwater oceanic island lenses have been developed by hydrogeologists during the last decade. Based on existing equations, this study focuses on the case of strip oceanic islands when three combined effects of climate change are observed to affect the freshwater lens volume and its groundwater resource renewal: sea-level rise, erosion, and change in groundwater recharge rates. New equations, integrating these combined effects of climate change on fresh groundwater resources are provided. These equations are solved by a novel methodology based on a Dupuit-Forchheimer groundwater flow model that allows for determination of the hydrogeological parameters included in the equations. The approach is illustrated with the strip island of Savary, which is located along the Pacific Coast of Canada in the province of British Columbia. This example illustrates, on the one hand, the volume depletion of the island freshwater lens and, on the other hand, the decrease of the renewal rate of groundwater. The proposed approach can be applied to any strip islands worldwide to assess the cumulative effects of sea-level rise and shore erosion on groundwater resources, depending on the predicted climate change scenarios. The results can then help decision-makers to anticipate the effects of climate change on the groundwater availability in strip oceanic islands and plan future groundwater use accordingly. Des solutions analytiques de forme fermée visant à estimer les conséquences du changement climatique sur les lentilles d’eau douce souterraine d’une ile océanique ont été développées par les hydrogéologues au cours de la dernière décennie. Sur la base des équations existantes, la présente étude se concentre sur le cas des îles océaniques étroites, où l’on observe trois effets conjugués du changement climatique affectant le volume de la lentille d’eau douce et le renouvellement de sa ressource e

The extraction of ore and minerals by underground mining often presents important risk for surface infrastructures. Several methods that have been developed to predict ground subsidence, and the influence function method (IFM) is one of the most efficient for predicting this phenomenon in the context of mining engineering. However, applying this method to a specific mining site requires adjustments that are difficult to achieve. In this paper, a methodology is proposed for adjusting the IFMs to each mining site. It is shown that the maximum subsidence depends on both the Width(W)/Height(H) and Length(L)/W ratios of mine panel. Moreover, the effect of the length variation becomes negligible for L/W ratio values greater than 4, but it is significant for values around 1. The influence angle of each mine panel has a significant effect on the subsidence, and a variation of 5° may lead to significant variations in the prediction. A coefficient of dimensions reduction (CDR) used for adjusting the IFM results in each mine panels is used to adjust the value of subsidence above the border of the mine panels. The appropriate influence angle and CDR parameters should be calculated for each mining region.

Carbon anodes are used in aluminium electrolysis. Their quality plays a major role in the stability of cell operation and energy consumption. The improvement of the quality of carbon anodes is essential to respond to the many challenges the aluminium industry is facing with respect to issues related to carbon loss, energy use, cell performance, and production cost, especially for high amperage cells. The presence of cracks increases the anode resistivity, and, as a result, power consumption, production cost, and greenhouse gas emissions also increase. Therefore, it is important to know how the cracks form during anode production. An industrial measurement campaign was carried out at the Aluminerie Alouette Inc. (AAI) plant in Sept-Îles, Québec, Canada. The effect of raw materials (type of coke, pitch, and butts), vibro-compaction (vibro-compactor type, balloon pressure, and vibration time), and the position of anodes in the baking furnace on anode cracking was investigated. It was found that the anode centre is the region that contains the most cracks compared to other parts of the anode. The cracks in the horizontal direction are more predominant than those in other directions. The raw materials and the operating parameters of each anode production step affect anode cracking.

A seismic microzonation study was conducted to refine the seismic hazard model for the city of Saguenay, Canada. The Quaternary geology underlying Saguenay shows complex glacial and post-glacial stratigraphy with a number of buried valleys filled with fluvioglacial and glaciomarine sediments. High impedance contrast between rock formations and surficial sediments is prone to seismic amplification. To evaluate their applicability, advantages and limitations in capturing the geological specificity of the study area, four site classification methods were applied: the current National Building Code of Canada (NBCC) and Eurocode 8, both mainly based on the average shear-wave velocity for the surficial sediments (VS,avg) and for the top 30 m (VS,30); a method based on the fundamental site period (T0); and a hybrid method based on the combination of VS,30, T0 and VS,avg. The study specifically aimed to evaluate the importance of the site classification parameters on the resulting microzonation maps. VS,30 is capable to present the geological and geotechnical site conditions, however, the results may be further improved by considering Vs,avg in shallow and T0 in thick layers of soil sediments as secondary parameters. The T0 method gives also satisfactory results with T0 showing a better correlation to Vs,30 than to Vs,avg. The versatile hybrid method may be challenging to apply in certain cases with its nine different site categories and parameters.

In addition to public health measures, including social distancing, masking, cleaning, surface disinfection, etc., ventilation and air filtration can be a key component of a multi-pronged risk mitigation strategy against COVID-19 transmission indoors. Electrostatic precipitators (ESP) have already proved their high performance in fluid filtration, particularly in industrial applications, to control exhaust gas emissions and remove fine and superfine particles from the flowing gas, using high-voltage electrostatic fields and forces. In this contribution, a high-voltage electrostatic sanitizer (ESS), based on the electrostatic precipitation concept, is proposed as a supportive measure to reduce indoor air infection and prevent the spread of COVID-19 coronavirus. The finite element method (FEM) is used to model and simulate the proposed ESS, taking into account three main mechanisms involving in electrostatic sanitization, namely electrostatic field, airflow, and aerosol charging and tracing, which are mutually coupled to each other and occur simultaneously during the sanitization process. To consider the capability of the designed ESS in capturing superfine particles, functional parameters of the developed ESS, such as air velocity, electric potential, and space charge density, inside the ESS are investigated using the developed FEM model. Simulation results demonstrate the ability of the designed ESS in capturing aerosols containing coronavirus, precipitating suspended viral particles, and trapping them in oppositely charged electrode plates.

In recent years, rock scouring or erosion downstream of dams has become an increasing dam safety concern. Several theoretical, semi-theoretical, semi-analytical and numerical methods can be used to assess the rock erosion in hydraulic structures. Semi-theoretical approaches determine the correlation between the erosive intensity of fluid flow and the resistive capacity of rock. Such approaches establish the scour thresholds as a function of erosive intensity of water and several rock mass indices by using in situ data and a curve-fitting approach. In some studies, the excavatability index, initially developed for rock mass stability analysis, was used to analyse the rock mass resistance in hydraulic erodibility analysis. The effectivity and weight of the geomechanical parameters used are yet to be determined on the basis of the erodibility phenomenon. The semi-analytical methods are developed on the basis of the mechanical and hydraulic interaction of rock mass and water. Four methods developed by Bollaert et al. are important in determining the erodibility in the plunge pool, but they are not applicable in the case of spillways. They used the comprehensive fracture mechanics for closed-end joints, quasi-steady impulsion, and dynamic impulsion (DI) for blocky rock erosion. The application of these methods to each site is necessary to identify constants that are difficult to determine. Few numerical methods are available to assess the rock mass erosion in hydraulic structures. In the case of numerical methods, the erosive agent is indistinct, and the hydraulic hazard parameter on the spillway surface is almost challenging to apply. This study comprehensively reviews the mechanism of erosion and the methods for assessing the risk of potential rock mass erosion downstream of dams and hydraulic structures. The advantages and disadvantages of all methods are discussed and the potential future research directions in this domain are proposed.

The rock mass erosion of dam spillways, a phenomenon involving the interaction between the hydraulic load of water and the capability of the rock mass to resist its destruction, remains a critical safety issue. The erosion resistance of a rock mass can be estimated through several erodibility indices, including those of Kirsten, Pells or Bollaert. Several indices have been developed to link rock resistance to the hydraulic parameters of water, i.e., the hydraulic load applied on a rock mass. The developed indices use the average flow velocity, the average shear stress on the bottom of the flow channel, the stress applied to the internal joints of fractured rock mass, the dynamic impulse force, and the power dissipation of water to represent the erosive force of water. From these indices, several methods of assessing hydraulic erosion have been developed, and all use the threshold line concept. Nonetheless, several uncertainties are associated with these methods. This paper presents and discusses the various means of calculating the erosive force of water as a hazard parameter for predicting potential rock erosion. The representativeness of these approaches is also discussed, and we clarify nuances associated with each method. We then provide guidelines for future research aimed at improving estimates of the erosive force of the water within spillway flow channels.

Human bodies are continuously generating information about our health. This information can be assessed by physiological tools that gauge bio-signals such as blood pressure, heart rate, and blood glucose. Computer scientists are obtaining knowledge on new technologies to manage these bio-signals using a range of equations and approaches. Currently, real-time monitoring, cloud computing, edge computing, and the Internet of Things are key technologies that can be applied in the environmental research and public health field. In light of these and many other challenges, a Special Issue entitled Computing Techniques for Environmental Research and Public Health has been dedicated to address the current status, challenges, and future research priorities for environmental research and public health. Starting from the above considerations, this Special Issue aims to investigate the impact of adopting advanced and innovative information computing-based algorithms in environmental research and public health field applications, including ones that take advantage of recent big data, compression, multichannel, sensor, and prediction techniques. This edition of the Special Issue is focused primarily on computing techniques for environmental research and public health applications with a particular emphasis on artificial intelligence and signal processing platforms. This issue is intended to provide a highly recognized international forum to present recent advances in the International Journal of Environmental Research and Public Health. We welcome both theoretical contributions as well as papers describing interesting applications. Papers were invited for this Special Issue considering aspects of this problem, including: • public health; • bio-signal processing; • the Internet of Things; • real-time monitoring; • cloud computing. After review, a total of seven papers have been accepted for publication in this issue.

The digital revolution is expected to surpass all previous economic transformations in scale, scope, and complexity. Digital technologies are making electrical grids more connected, more reliable, and sustainable. Several efforts have been made to revamp the electric grid and modernize century-old systems. In the near future, we expect to see a revolution in power grind monitoring with incredible results through artificial intelligence and big data, drones, among others. The business opportunity for using drones in the energy sector is impressive, although very few companies have joined in its implementation. The drone allows the safe remote overflight of high voltage power lines. They can be deployed to detect, inspect, and diagnose the defects of the power line infrastructure. In this article, we provide the state of the art of using drones in smart grid monitoring. We demonstrate and propose an architecture based on Faster R-CNN for detecting ice accretion on power lines. Finally, we shed light on opportunities and future trends of these emerging technologies that can guide future research directions.

The most common methods used to evaluate the potential hydraulic erosion of rock are index-based methods, which correlate the force of flowing water and the capacity of a rock to resist erosion. This capacity is evaluated using erodibility indices, which combine a set of specific geological parameters. Nonetheless, there exists no clear consensus in regard to the relative importance assigned to the geological parameters. Our study proposes (i) a review of the existing index-based methods used to evaluate the hydraulic erodibility of rock, and (ii) a method to determine the relative importance of the geological parameters governing the erodibility of rock. The developed approach relies on a large data set of case studies providing details of unlined spillways subjected to erosion. We demonstrate that the analyzed geological parameters can be classified according to their relative importance—from highest to lowest—as follows: (1) joint shear strength, (2) nature of the potentially eroding surface, (3) rock block volume, (4) joint opening, (5) rock block's shape and orientation relative to flow direction, and (6) the rock mass deformation module. This ordering of the relative importance of the geological parameters agrees largely with previously established orderings that were based on field observations.

Recent hydrogeological mapping throughout the Saguenay-Lac-Saint-Jean region in Quebec, Canada, has yielded a very comprehensive geodatabase (GDB) on groundwater and aquifer systems, designed to fulfil the requirements of groundwater management at the regional level. The high density of observed hydrogeological data points also makes the GDB useful for many local or sub-regional applications. Recently acquired data from continuing geotechnical or groundwater-related activities must be integrated into the GDB in order to maintain its relevance for a variety of problems concerning groundwater quality, its management and its protection. When it is consistently updated, such a hydrogeological (HG) GDB also stands as a critical and constantly evolving link between the scientific community, government agencies, regional and municipal authorities, and ultimately the population who draw upon the groundwater resource. The HG-GDB represents a central hub of effective collaboration between scientists and data users, and the intent is that it may lead to more appropriate decision-making when faced with different issues and/or when taking actions that may include applied groundwater research projects. Groundwater data transfer becomes an information exchange process, an essential tool facilitating the sustainable management of groundwater resources.

The DRASTIC index used to assess the vulnerability of aquifers to contamination, has been subject to various adjustments to improve its reliability. These adjustments include adding and/or eliminating certain aquifer factors and modifying the factor weights. Nonetheless, there is no consensus about which factors, or their respective weights, are most important for assessing aquifer vulnerability. In the present study, we propose an operational methodology that: (1) identifies the relevant factors for assessing aquifer vulnerability to contamination; and (2) determines the relative importance of the selected factors. We applied this approach to a large data set of granular aquifers from a region in Canada, which includes information for DRASTIC factors, combined with groundwater quality and land-use data. We found that for our study region, topography (terrain-slope) is an irrelevant factor for assessing the vulnerability of aquifers to contamination. On the other hand, the relevant factors ranked according to their relative importance (from highest to lowest), are (1) water table depth; (2) hydraulic conductivity; (3) characteristics of vadose zone materials; and (4) recharge. Our approach can serve as an initial step for identifying the relevant aquifer factors when assessing aquifer vulnerability and determining the relative importance of the relevant factors to validate weights attributed to these factors. Our methodology can help adapt index-based methods of aquifer vulnerability assessment to a range of study regions.

The specific length of a tunnel (STL) and a new analytical model for calculating the block surface area of the rock mass are introduced. First, a method for determining the appropriate length of a tunnel for a numerical simulation is described. The length is then used to examine the correlation between the inflow rate to the tunnel and the block volume, the block surface area, and the fracture intensity (P32) through analytical and numerical modeling. The results indicate that the length of the tunnel should at least be equal to the least common multiple (LCM) of the apparent spacings of the joint sets at the wall of the tunnel to obtain the more reliable and immediate results for the inflow rate to a tunnel that is excavated in a fractured rock mass. A new analytical model was developed to calculate the block surface area and determine the essential joint set parameters, which include the dip, dip direction, and spacing. The determination of the rock block characteristics through numerical modeling requires considering the intact block for calculations. The results indicated that the inflow rate to the tunnel increased with an increase in fracture intensity and a decrease in block volume and surface area. The STL and the analytical model used for calculating the block surface area are validated through numerical simulations with 3DEC software version 7.0.

Bushveld anorthosites commonly contain the so-called “mottles” comprising irregular, typically centimetric domains of oikocrystic pyroxene or olivine enclosing small, embayed plagioclase grains. The mottles were traditionally interpreted to result from solidification of trapped intercumulus liquid or via in situ crystallisation at the top of the crystal mush. Here, we present microtextural and compositional data of a mottle to place further constraints on the formation of anorthosite layers. Element maps generated by scanning electron microscopy reveal that plagioclase within and around the mottle has markedly elevated An contents (up to An95) relative to the host anorthosite and is strongly reversely zoned. Other unusual features, some of which were reported previously, include a halo of sub-vertically oriented, acicular phlogopite around the mottle, elevated contents of disseminated sulfides, and relatively evolved yet Ni-rich olivine (Fo71–75, 3000 ppm Ni). These features are interpreted to result from reactive porous flow of hot, acidic fluid enriched in nickel and sulfur through proto norite. The fluids dissolved mafic minerals and leached alkalis from the outer rims of plagioclase grains. Reconnaissance studies suggest that reversed zoning of plagioclase is a common feature in Bushveld norite and anorthosite. This implies that reactive porous flow could have been far more pervasive than currently realised and that Bushveld anorthosite layers formed through recrystallisation of norites.

Structural shape optimization plays an important role in the design of wind‐sensitive structures. The numerical evaluation of aerodynamic performance for each shape search and update during the optimization process typically involves significant computational costs. Accordingly, an effective shape optimization algorithm is needed. In this study, the reinforcement learning (RL) method with deep neural network (DNN)‐based policy is utilized for the first time as a shape optimization scheme for aerodynamic mitigation of wind‐sensitive structures. In addition, “tacit” domain knowledge is leveraged to enhance the training efficiency. Both the specific direct‐domain knowledge and general cross‐domain knowledge are incorporated into the deep RL‐based aerodynamic shape optimizer via the transfer‐learning and meta‐learning techniques, respectively, to reduce the required datasets for learning an effective RL policy. Numerical examples for aerodynamic shape optimization of a tall building are used to demonstrate that the proposed knowledge‐enhanced deep RL‐based shape optimizer outperforms both gradient‐based and gradient‐free optimization algorithms.

Automated vehicles are becoming popular across the communities of e-transportation across the globe. Hybrid electric vehicles and autonomous vehicles have been subjected to critical research for decades. The research outcomes pertinent to this topic in the literature have been motivated by the industry and researchers to emphasize automated vehicles. Part 1 of this survey addressed the critical aspects that concern the bidirectional converter topologies and condition monitoring activities. In the present part, 24- and 77-GHz low-profile printed antennas are studied for automotive radar applications. These antennas are mounted on automated vehicles to avoid collision and are used for radio tracking applications. The present paper states the types of antenna structures, feed mechanisms, dielectric material requirements, design techniques, performance parameters, and challenges at 24- and 77-GHz resonating frequency applications. The recent developments in feed methodologies, beam scanning concepts, and the effect of sidelobe levels are addressed. Furthermore, the reasons behind the transition from 24 to 77 GHz are reported in detail. The recent advances in the application of various sensor schemes in an automated vehicle have also been discussed.

A critical survey has been conducted on high energy-efficient bidirectional converters, various topologies that effectively meet the automated vehicle requirements, and 24 GHz/77 GHz low-profile antennas (for automotive radar applications). The present survey has been identified into two parts on the current topic of study as perspectives and challenges. Part 1 of this survey covers energy-efficient power electronic convertor topologies and condition monitoring aspects of convertors to enhance the lifespan and improve performance. Condition-monitoring issues concerning the abnormalities of electrical components, high switching frequencies, electromagnetic interference, leakage currents, and unwanted joint ruptures have also been emphasized. It is observed that composite converters are proficient for automated hybrid electric vehicles due to fast dynamic response and reduced component count. Importantly, electrical component failures in power electronic converters are most common and need attention for the effective operation of the bidirectional converters. Hence, condition monitoring implementation schemes have also been summarized. Part 2 of this survey focuses on 24 and 77 GHz low-profile (microstrip-based) antennas for automotive radar applications, types of antenna structures, feed mechanisms, dielectric material requirements, design techniques, and performance parameters. The discussion in Part 2 also covers feed methodologies, beam scanning concepts, and side-lobe levels on the autonomous vehicle communication activities.

Previously, studies reported that falls analysis is possible in the elderly, when using wearable sensors. However, these devices cannot be worn daily, as they need to be removed and recharged from time-to-time due to their energy consumption, data transfer, attachment to the body, etc. This study proposes to introduce a radar sensor, an unobtrusive technology, for risk of falling analysis and combine its performance with an instrumented insole. We evaluated our methods on datasets acquired during a Timed Up and Go (TUG) test where a stride length (SL) was computed by the insole using three approaches. Only the SL from the third approach was not statistically significant (p = 0.2083 > 0.05) compared to the one provided by the radar, revealing the importance of a sensor location on human body. While reducing the number of force sensors (FSR), the risk scores using an insole containing three FSRs and y-axis of acceleration were not significantly different (p > 0.05) compared to the combination of a single radar and two FSRs. We concluded that contactless TUG testing is feasible, and by supplementing the instrumented insole to the radar, more precise information could be available for the professionals to make accurate decision.

Smart grids (SG) emerged as a response to the need to modernize the electricity grid. The current security tools are almost perfect when it comes to identifying and preventing known attacks in the smart grid. Still, unfortunately, they do not quite meet the requirements of advanced cybersecurity. Adequate protection against cyber threats requires a whole set of processes and tools. Therefore, a more flexible mechanism is needed to examine data sets holistically and detect otherwise unknown threats. This is possible with big modern data analyses based on deep learning, machine learning, and artificial intelligence. Machine learning, which can rely on adaptive baseline behavior models, effectively detects new, unknown attacks. Combined known and unknown data sets based on predictive analytics and machine intelligence will decisively change the security landscape. This paper identifies the trends, problems, and challenges of cybersecurity in smart grid critical infrastructures in big data and artificial intelligence. We present an overview of the SG with its architectures and functionalities and confirm how technology has configured the modern electricity grid. A qualitative risk assessment method is presented. The most significant contributions to the reliability, safety, and efficiency of the electrical network are described. We expose levels while proposing suitable security countermeasures. Finally, the smart grid’s cybersecurity risk assessment methods for supervisory control and data acquisition are presented.

Carbon anodes are used in the electrolytic production of aluminum. The quality of anodes is directly related to the production cost, carbon and energy consumption, and environmental emissions. It is desired that the anodes have high density, low porosity/cracks, low electrical resistivity as well as low air and CO2 reactivities. Low resistivity of anodes reduces energy required to produce aluminum during electrolysis. The presence of cracks and pores increases the anode electrical resistivity. Therefore, it is important to know how and when the pores and cracks form during the anode production so that the necessary actions could be taken to prevent their formation. A study was carried out to investigate the effect of different anode production parameters such as anode composition, type of raw material used, time and top-former bellow pressure of vibro-compactor, green anode cooling medium, and heating rate used during baking on the crack formation. The anodes are fabricated at the carbon laboratory of University of Quebec at Chicoutimi (UQAC) and characterized by measuring their properties (density, electrical resistivity, and surface crack density). The anode properties, hence the anode quality, were correlated with the anode production parameters. Also, their tomographic analysis was carried out to visualize and quantify the internal cracks.

In order to study ice protection systems for rotating blades, a new experimental setup has been developed at the Anti-Icing Materials International Laboratory (AMIL). This system consists of two small-scale rotating blades in a refrigerated icing wind tunnel where atmospheric icing can be simulated. Power is brought to the blades through a slip ring, through which the signals of the different sensors that are installed on the blades also pass. As demonstrated by the literature review, this new setup will address the need of small-scale wind tunnel testing on electrically powered rotating blades. To test the newly designed apparatus, preliminary experimentation is done on a hybrid ice protection system. Electrothermal protection is combined with different surface coatings to measure the impact of those coatings on the power consumption of the system. In anti-icing mode, the coatings tested did not reduce the power consumption on the system required to prevent ice from accumulating on the leading edge. The coatings however, due to their hydrophobic/superhydrophobic nature, reduced the power required to prevent runback ice accumulation when the leading edge was protected. One of the coatings did not allow any runback accumulation, limiting the power to protect the whole blades to the power required to protect solely the leading edge, resulting in a potential 40% power reduction for the power consumption of the system. In de-icing mode, the results with all the substrates tested showed similar power to achieve ice shedding from the blade. Since the coatings tested have a low icephobicity, it would be interesting to perform additional testing with icephobic coatings. Also, a small unheated zone at the root of the blade prevented complete ice shedding from the blade. A small part of the ice layer was left on the blade after testing, meaning that a cohesive break had to occur within the ice layer, and therefore impacting the results. Improvements to the setup will be done

This paper proposes a system in package (SiP) for ultrasonic ranging composed of a 4 × 8 matrix of piezoelectric micromachined ultrasonic transducers (PMUT) and an interface integrated circuit (IC). The PMUT matrix is fabricated using the PiezoMUMPS process and the IC is implemented in the AMS 0.35 µm technology. Simulation results for the PMUT are compared to the measurement results, and an equivalent circuit has been derived to allow a better approximation of the load of the PMUT on the IC. The control circuit is composed of a high-voltage pulser to drive the PMUT for transmission and of a transimpedance amplifier to amplify the received echo. The working frequency of the system is 1.5 MHz.

In gold-endowed greenstone belts, ore bodies generally correspond to orogenic gold systems (OGS) formed during the main deformation stage that led to craton stabilization (syntectonic period). Most OGS deposits postdate and locally overprint magmatic-hydrothermal systems, such as Au-Cu porphyry that mostly formed during the main magmatic stage (synvolcanic period) and polymetallic intrusion-related gold systems (IRGS) of the syntectonic period. Porphyries are associated with tonalite-dominated and sanukitoid plutons, whereas most IRGS are related to alkaline magmatism. As reviewed here, most intrusion-associated mineralization in the Abitibi greenstone belt is the result of complex and local multistage metallogenic processes. A new classification is proposed that includes (1) OGS and OGS-like deposits dominated by metamorphic and magmatic fluids, respectively; (2) porphyry and IRGS that may contain gold remobilized during subsequent deformation episodes; (3) porphyry and IRGS that are overprinted by OGS. Both OGS and OGS-like deposits are associated with crustal-scale faults and display similar gold-deposition mechanisms. The main difference is that magmatic fluid input may increase the oxidation state and CO2 content of the mineralizing fluid for OGS-like deposits, while OGS are characterized by the circulation of reduced metamorphic fluids. For porphyry and IRGS, mineralizing fluids and metals have a magmatic origin. Porphyries are defined as base metal and gold-bearing deposits associated with large-volume intrusions, while IRGS are gold deposits that may display a polymetallic signature and that can be associated with small-volume syntectonic intrusions. Some porphyry, such as the Côté Gold deposit, demonstrate that magmatic systems can generate economically significant gold mineralization. In addition, many deposits display evidence of multistage processes and correspond to gold-bearing or gold-barren magmatic-hydrothermal systems overprinted by OGS or by gold

This paper focusses on obtaining a better understanding of the subsurface geology of the Chibougamau area, in the northeast of the Abitibi greenstone belt (Superior craton), using geophysical data collected along a 128 km long traverse with a rough southwest–northeast orientation. We have constructed two-dimensional (2D) models of the study area that are consistent with newly collected gravity data and high-resolution magnetic data sets. The initial models were constrained at depth by an interpretation of a new seismic section and at surface by the bedrock geology and known geometry of lithological units. The attributes of the model were constrained using petrophysical measurements so that the final model is compatible with all available geological and geophysical data. The potential-field data modelling resolved the geometry of plutons and magnetic bodies that are transparent on seismic sections. The new model is consistent with the known structural geology, such as open folding, and provides an improvement in estimating the size, shape, and depth of the Barlow and Chibougamau plutons. The Chibougamau pluton is known to be associated with Cu–Au magmatic-hydrothermal mineralisation and, as the volume and geometry of intrusive bodies is paramount to the exploration of such mineralisation, the modelling presented here provides a scientific foundation to exploration models focused on such mineralisation. L’article est axé sur l’établissement d’une meilleure compréhension de la géologie du sous-sol de la région de Chibougamau, dans le nord-est de la ceinture de roches vertes de l’Abitibi (craton du Supérieur), à la lumière de données géophysiques recueillies le long d’une traverse de 128 km d’orientation approximativement sud-ouest–nord-est. Nous avons construit des modèles bidimensionnels (2D) de la région à l’étude qui concordent avec des données gravimétriques et des ensembles de données magnétiques de haute résolution nouvellement acquis. Les modèles initiaux ont ét

Alkali-silica reaction (ASR) is one of the most damaging mechanisms affecting concrete structures worldwide. ASR effects on the durability and serviceability of damaged concrete are widely known and fairly well understood. However, the structural implications are still unclear, and a number of contradictory data are found in the literature, especially regarding shear behavior. The influence of ASR distressed reinforced concrete on aggregate interlock is presented in this paper. Push-off specimens having different transverse reinforcement ratios were fabricated with ASR reactive coarse aggregates. The specimens were monitored over time and displayed different levels of expansion. Results indicated that ASR-induced expansion and damage were affected by the transverse reinforcement ratio. However, little to no aggregate interlock reduction was observed on ASR-affected specimens up to moderate expansion levels (about 0.12%). It was found that there were two controlling and competing mechanisms that affected aggregate interlock for ASR-affected specimens: the beneficial effects of chemical prestressing and the detrimental ASR-induced damage.

Two high-resolution seismic reflection profiles acquired north and south of Chibougamau, located in the northeast of the Abitibi subprovince of Canada, help understand historic volcanically hosted massive sulfide (VMS) deposits and hydrothermal Cu–Au mineralization found there. Major faults crossed by the profiles include the Barlow fault in the north and the Doda fault and the Guercheville fault in the south, all targets of this study that seeks to determine spatial relationships with a known metal endowment in the area. Common-offset DMO corrections and common-offset pre-stack time migrations (PSTMs) were considered. Irregularities of the trace midpoint distribution resulting from the crooked geometry of both profiles and their relative contribution to the DMO and PSTM methods and seismic illumination were assessed in the context of the complex subsurface architecture of the area. To scrutinize this contribution, seismic images were generated for offset ranges of 0–9 km using increments of 3 km. Migration of out-of-plane reflections used cross-dip element analysis to accurately estimate the fault dip. The seismic imaging shows the thickening of the upper-crustal rocks near the fault zones along both profiles. In the northern seismic reflection section, the key geological structures identified include the Barlow fault and two diffraction sets imaged within the fault zone that represent potential targets for future exploration. The south seismic reflection section shows rather a complicated geometry of two fault systems. The Guercheville fault observed as a subhorizontal reflector connects to a steeply dipping reflector. The Doda fault dips subvertical in the shallow crust but as a steeply dipping reflection set at depth. Nearby gold showings suggest that these faults may help channel and concentrate mineralizing fluids.

To conduct a successful geomechanical characterization of rock masses, an appropriate interpretation of lithological heterogeneity should be attained by considering both the geological and geomechanical data. In order to clarify the reliability and applicability of geological surveys for rock mechanics purposes, a geomechanical characterization study is conducted on the heterogeneous rock mass of Niobec Mine (Quebec, Canada), by considering the characteristics of its various identified lithological units. The results of previous field and laboratory test campaigns were used to quantify the variability associated to intact rock geomechanical parameters for the different present lithological units. The interpretation of geomechanical similarities between the lithological units resulted in determination of three main rock units (carbonatite, syenite, and carbonatite-syenite units). Geomechanical parameters of these rock units and their associated variabilities are utilized for stochastic estimation of geomechanical parameters of the heterogeneous rock mass using the Monte Carlo Simulation method. A comparison is also made between the results of probabilistic and deterministic analyses to highlight the presence of intrinsic variability associated with the heterogeneous rock mass properties. The results indicated that, for the case of Niobec Mine, the carbonatite-syenite rock unit could be considered as a valid representative of the entire rock mass geology since it offers an appropriate geomechanical approximation of all the present lithological units at the mine site, in terms of both the magnitude and dispersion of the strength and deformability parameters.

This contribution describes maps of the Copper Cliff Embayment (CCE) and Offset (CCO) dyke. The associated study attempts to unravel the mode of melt emplacement and the role of pre-impact faults in the deformation of the southern part of the Sudbury Igneous Complex (SIC). This contribution summarizes field observations (maps and images) and structural measurements. In addition, perspective views of the 3D Move model of the CCE and CCO dyke are provided. This data can be used by researchers and exploration geologists working in the Sudbury mining camp as a basis for future mapping, research and exploration efforts in the Copper Cliff area.

Accurate determination of the materials’ strength and ductility in the semi-solid state at near-solidus temperatures is essential, but it remains a challenging task. This study aimed to develop a new method to determine the stress-strain evolution in the semi-solid state of aluminum alloys within the Gleeble 3800 unit. Stress evolution was determined by the newly developed “L-gauge” method, which converted the displacement of the “restrained” jaw, measured using an L-gauge, into the force. This method gives the possibility to determine the flow stress more accurately, especially for the very low stress rang (1–10 MPa) in the semi-solid state at near-solidus temperatures. The digital image correlation technique implemented in the Gleeble unit allowed effective measurement of the heterogeneous strain fields evolving within the specimen under tensile loading. Therefore, the stress-strain curves measured in the semi-solid state help to better understand the alloy’s susceptibility to hot tearing. The results of an AA6111 alloy under different liquid fractions (2.8% at 535 °C and 5.8% at 571 °C) were demonstrated. The reliable stress-strain data and heterogenous strain distribution are beneficial to develop the thermomechanical models and hot-tearing criteria.

Icing on surfaces such as cables or high-voltage insulators may often lead to severe safety issues such as power outages in cold winter conditions. Conventional methods used to tackle such icing problems include mechanical deicing, where the ice is scraped or broken, and chemical deicing, where deicers such as ethylene glycol are used. However, the best approach to addressing these issues is to prevent ice formation in the first place. Research in the past few decades have shown hydrophobic and superhydrophobic surfaces to be effective in reducing ice adhesion. We used the concept of water repellency to turn an aluminum surface superhydrophobic to minimize ice adhesion on these surfaces. However, to render these surfaces also applicable to insulating surfaces, we also demonstrated the adaptability of the concept on a low dielectric oxide, TiO2, to an aluminum surface with icephobic properties. This work demonstrates the importance of the coexistence of rough nanostructures as well as low-surface-energy compositions on a surface to make it superhydrophobic and icephobic and is applicable on metals and insulating surfaces.

In this contribution, a new dissolved gas analysis (DGA) method combining key gases and ratio approaches for power transformer fault diagnostic is presented. It is based on studying subsets and uses the five main hydrocarbon gases including hydrogen (H2), methane (CH4), ethane (C2H6), ethylene (C2H4), and acetylene (C2H2). The proposed method uses 475 samples from the dataset divided into subsets formed from the maximum and minimum(s) concentrations of the whole dataset. It has been tested on 117 DGA sample data and validated on the International Electrotechnical Commission (IEC) TC10 database. The performance of the proposed diagnostic method was evaluated and compared with the following diagnostic methods: IEC ratios method, Duval's triangle (DT), three ratios technique (TRT), Gouda's triangle (GT), and self-organizing map (SOM) clusters. The results found were analysed by computer simulations using MATLAB software. The proposed method has a diagnosis accuracy of 97.42% for fault types, as compared to 93.16% of TRT, 96.58% of GT method, 97.25% of SOM clusters method and 98.29% of DT method. However, in terms of fault severity, the proposed method has a diagnostic accuracy of 90.59% as compared to 78.90% of SOM clusters method, 83.76% of TRT, 88.03% of DT method, and 89.74% of GT method.

In this article we hypothesized that the arrow of time and space evolve in a discontinuous way in the form of quanta (t=ntp, s=mlp). We applied this reasoning to the light geodesics of Schwarzschild’s metric (dsmin=lp) and obtained different characteristics of the BH. Indeed, quantum light geodesics show that inside the BH a WH is formed and the mass (energy) is not directing towards the singularity r→0 but rather around the BH near the EH as a thick skin (tickness ). The total relativistic energy invariant is satisfied for the entire route of the photons. Subsequently, as mass (energy) is found directly at the EH, we applied the quantum tunnel effect in simple semi-classical analysis, and we obtained that particles like protons can leave the EH and that the energy associated with them is in the order of magnitude of Hawking’s radiation. However, the energy of the protons is not necessarily identified with that of the black body (photonic or electromagnetic). Finally, it would be interesting to see the impacts of this quantum light geodesics (dsmin=lp) on other cases like Kerr’s metric.

Knowledge of the stratigraphic architecture and geotechnical properties of surficial soil sediments is essential for geotechnical risk assessment. In the Saguenay study area, the Quaternary deposits consist of a basal till layer and heterogeneous post-glacial deposits. Considering the stratigraphic setting and soil type heterogeneity, a multistep stochastic methodology is developed for 3D geological modelling and quantification of the associated uncertainties. This methodology is adopted for regional studies and involves geostatistical interpolation and simulation methods. Empirical Bayesian kriging (EBK) is applied to generate the bedrock topography map and determine the thickness of the till sediments and their uncertainties. The locally varying mean and variance of the EBK method enable accounting for data complexity and moderate nonstationarity. Sequential indicator simulation is then performed to determine the occurrence probability of the discontinuous post-glacial sediments (clay, sand and gravel) on top of the basal till layer. The individual thickness maps of the discontinuous soil layers and uncertainties are generated in a probabilistic manner. The proposed stochastic framework is suitable for heterogeneous soil deposits characterised with complex surface and subsurface datasets.

Machine learning is widely used as a panacea in many engineering applications including the condition assessment of power transformers. Most statistics attribute the main cause of transformer failure to insulation degradation. Thus, a new, simple, and effective machine-learning approach was proposed to monitor the condition of transformer oils based on some aging indicators. The proposed approach was used to compare the performance of two machine-learning classifiers: J48 decision tree and random forest. The service-aged transformer oils were classified into four groups: the oils that can be maintained in service, the oils that should be reconditioned or filtered, the oils that should be reclaimed, and the oils that must be discarded. From the two algorithms, random forest exhibited a better performance and high accuracy with only a small amount of data. Good performance was achieved through not only the application of the proposed algorithm but also the approach of data preprocessing. Before feeding the classification model, the available data were transformed using the simple k-means method. Subsequently, the obtained data were filtered through correlation-based feature selection (CFsSubset). The resulting features were again retransformed by conducting the principal component analysis and were passed through the CFsSubset filter. The transformation and filtration of the data improved the classification performance of the adopted algorithms, especially random forest. Another advantage of the proposed method is the decrease in the number of the datasets required for the condition assessment of transformer oils, which is valuable for transformer condition monitoring.

In this article, a novel frequency slot-based switchable antenna fabricated on flexible and nonflexible materials is presented for suitable reconfigurable radiations of Bluetooth, WiMAX, and upper WLAN applications. Initially, the performance of this structure was simulated using a CSTTM simulator and evaluated experimentally using a nonflexible FR4 structure. The same antenna was implemented on a flexible (jean) substrate with a relative permittivity of 1.7. The proposed textile antenna prototypes were fabricated by optimal dimensions of an E-shaped slot with a variation on the shape of the ground layer, integrated using a crossed T-shaped strip with ON/OFF switchable state operations. The proposed antenna prototype is compact (20 × 20 mm2), providing switchable radiations with tri bands, has frequencies ranged at 2.36–2.5 GHz for Bluetooth, 3.51–3.79 GHz and 5.47–5.98 GHz for the distinct bands of WiMAX and WLAN, respectively, as well as part of UWB operations.

Frequency response analysis is a powerful tool for mechanical fault diagnostics in power transformers. However, interpretation schemes still today depend on expert analyses, mainly because of the complex structure of power transformers. One of the fundamental shortcomings of experimental investigations is that mechanical deformations cannot be managed on real transformers to obtain data for different scenarios because they are too destructive. To address this issue in a systematic way, the current research used a specially designed laboratory transformer model that allows mechanical defects to be introduced so its frequency response can be evaluated under different conditions. The key feature of this model is the non-destructive interchangeability of its winding sections, allowing reproducibility and repeatability of frequency response measurements. Numerical indices were compared over key performance indicators (linearity, sensitivity and monotonicity). The analysis indicated that comparative standard deviation offered promising results for evaluation of mechanical deformations on the laboratory winding model given its monotonic behaviour, sensitivity and linear increase with fault severity. Additionally, support vector machine learning, radial basis function neural network and the statistical k-nearest neighbour method were used for fault classification with different strategies and configurations. While limited data from different transformers are used in the available literature, the approach discussed here considers 371 measurements from the same transformer model. The test results are supportive and demonstrate great accuracy when machine learning is used for winding fault classification.

Optical code division multiple access (OCDMA) shows limitations in terms of the inefficient bandwidth utilization and low spectral density with one-dimensional (1D) codes. To overcome these limitations, a novel design is presented using a two dimensional (2D) spectral/spatial multiwavelength coding scheme. The proposed code is constructed using a 1D balanced incomplete block design (BIBD) technique. Theoretical and analytical results indicate that the proposed code provided improvement in the number of simultaneous users, code construction, and cross-correlation and minimized noise. Moreover, the bandwidth requirements can be minimized, and it can provide flexibility in addressing code sequences. Finally, results were compared with existing spectral-spatial 2D codes such as diagonal eigenvalue unity (DEU) and 2D diluted perfect difference (DPD). It was observed that the 2D-BIBD code fulfilled optical transmission needs with minimum effective source power (Psr = −27.5 dBm) when compared to 2D-DEU (−26.5 dBm) and 2D-DPD (−25.5 dBm) codes. Overall, our results suggested that the performance of BER for the proposed code was 72% and 22% higher than the existing 2D-DPD and 2D-DEU codes, respectively.

In the present work, individual/combined additions of transition elements (V, Zr and Mo) were introduced into Al-7Si-0.6Cu-0.35Mg foundry alloy at different cooling rates to study their influence on the precipitation behaviour of dispersoids. Results showed that both individual and combined additions of V, Zr, Mo lead to the formation of dispersoids but with different composition, morphology and number density during solution treatment. The addition of V produces the precipitation of both (Al,Si)3M dispersoids and α-dispersoids, while the Zr addition promotes (Al,Si)3M type dispersoids but inhibits the formation of α-Al(Mn,Fe)Si dispersoids. The addition of Mo effectively promotes α-Al(Mn,Mo,Fe)Si dispersoids and significantly reduces the dispersoid size and increase the number density of dispersoids. The combined addition of V, Zr and Mo produces the largest number of finer dispersoids among all five alloys studied, but the most dispersoids are (Al,Si)3M. The (Al,Si)3M dispersoids and α-dispersoids have the rod-like and block-like morphologies, respectively. High cooling rate can generally refine the dispersoids and increase their number density, while it also increases the proportion of (Al,Si)3M dispersoids.

[EN] The gSeaGen code is a GENIE-based application developed to efficiently generate high statistics samples of events, induced by neutrino interactions, detectable in a neutrino telescope. The gSeaGen code is able to generate events induced by all neutrino flavours, considering topological differences between track-type and shower-like events. Neutrino interactions are simulated taking into account the density and the composition of the media surrounding the detector. The main features of gSeaGen are presented together with some examples of its application within the KM3NeT project. Program summary Program Title: gSeaGen CPC Library link to program files: http://dx.doi.org/10.17632/ymgxvy2br4.1 Licensing provisions: GPLv3 Programming language: C++ External routines/libraries: GENIE [1] and its external dependencies. Linkable to MUSIC [2] and PRO-POSAL [3]. Nature of problem: Development of a code to generate detectable events in neutrino telescopes, using modern and maintained neutrino interaction simulation libraries which include the state-of-the-art physics models. The default application is the simulation of neutrino interactions within KM3NeT [4]. Solution method: Neutrino interactions are simulated using GENIE, a modern framework for Monte Carlo event generators. The GENIE framework, used by nearly all modern neutrino experiments, is considered as a reference code within the neutrino community. Additional comments including restrictions and unusual features: The code was tested with GENIE version 2.12.10 and it is linkable with release series 3. Presently valid up to 5 TeV. This limitation is not intrinsic to the code but due to the present GENIE valid energy range. References: [1] C. Andreopoulos at al., Nucl. Instrum. Meth. A614 (2010) 87. [2] P. Antonioli et al., Astropart. Phys. 7 (1997) 357. [3] J. H. Koehne et al., Comput. Phys. Commun. 184 (2013) 2070. [4] S. Adrián-Martínez et al., J. Phys. G: Nucl. Part. Phys. 43 (2016) 084001.

One of the promising tasks in education lies in reforming it into the knowledge economy, integrating and creating a market oriented towards results of intellectual activity. On the other hand, globalization process requires transition of the educational environment to the format of information, communication and digital space. Primarily these areas are set as the nodal tasks, which directs authors of this article to the comparative analysis of educational system making it possible to identify general and particular, positive or negative consequences and characteristics of digitalization in the higher education system. In accordance with current trends and processes of globalization and informatization, the authors are considering the prospects for interaction and mutual influence of Smart technologies used in building a future educational model in the higher education area. Technological innovations today are called upon not only to qualitatively change methods, forms and technologies in the education content, but rather to train personnel capable of operating in the new information and telecommunication community. Therefore, studying the influence and the capabilities of modern digital technologies that meet needs of society, on the one hand, and, on the other hand, contribute to formation of professional competencies in students, which requires major alterations in the learning process, changes in its state towards flexibility, adaptation, personalization, continuity, multidimensionality and systematicity, becomes of specific relevance for authors of this article.

A model of flotation was developed and applied to alumina in the aluminum electrolysis cell. The conditions of flotation for alumina on the cryolitic bath surface were determined for disc and sphere geometries. The contact angle between alumina and cryolitic bath, which had not been found in the literature, was measured and it was found to be around 30 deg. Experiments with compressed alumina discs on the cryolitic bath surface were conducted, and the results were compared to the model. The experiments showed how impurities on the bath surface influence the flotation; and how a slight asymmetry in the system may accelerate sinking.

The determination of the flow rate in the underground excavation is a very important parameter in the design of the structures. Among all parameters that have an impact on the inflow rate to the tunnel, the hydraulic gradient is one of the most effective one that, according to Darcy’s law, controls the tunnel inflow rate. An empirical-numerical equation is proposed for the determination of the vertical hydraulic gradient in the wall of a tunnel excavated below a water table. The horizontal hydraulic gradient is not supposed to have a significant impact on the tunnel inflow rate as its value is very low. By contrast, the existing vertical hydraulic gradient is among the most effective parameters. On the other hand, in the case of an underground excavation, no equation exists for the determination of the hydraulic gradient that considers more than one parameter, i.e., the depth. Using the results of the numerical simulations, it was deduced that the depth of the tunnel, the ratio between principal hydraulic conductivities, and their relevant directions are the most effective parameters that have a significant influence on the hydraulic gradient and inflow rate to the underground tunnels. The resultant hydraulic gradients in the vicinity of the wall of the tunnel were obtained using the RS2 Rocscience software. The mathematical relationship between the input data, i.e., the depth (z), ratio between hydraulic gradients (a) and their relevant directions (α), and the result of the simulation, i.e., the hydraulic gradient (iz), have been derived by curve fitting. Finally, for each orientation of the principal hydraulic conductivity, an equation is proposed for the calculation of the hydraulic gradient. La détermination du débit dans une excavation souterraine est un paramètre très important dans la conception des structures. Parmi tous les paramètres qui ont un impact sur le débit d'entrée dans le tunnel, le gradient hydraulique est l'un des plus influents qui, selon la lo

The feasibility and efficacy of improving the mechanical response of Al–Mg–Si 6082 structural alloys during high temperature exposure through the incorporation of a high number of α-dispersoids in the aluminum matrix were investigated. The mechanical response of the alloys was characterized based on the instantaneous high-temperature and residual room-temperature strengths during and after isothermal exposure at various temperatures and durations. When exposed to 200 °C, the yield strength (YS) of the alloys was largely governed by β” precipitates. At 300 °C, β” transformed into coarse β’, thereby leading to the degradation of the instantaneous and residual YSs of the alloys. The strength improvement by the fine and dense dispersoids became evident owing to their complementary strengthening effect. At higher exposure temperatures (350–450 °C), the further improvement of the mechanical response became much more pronounced for the alloy containing fine and dense dispersoids. Its instantaneous YS was improved by 150–180% relative to the base alloy free of dispersoids, and the residual YS was raised by 140% after being exposed to 400–450 °C for 2 h. The results demonstrate that introducing thermally stable dispersoids is a cost-effective and promising approach for improving the mechanical response of aluminum structures during high temperature exposure.

The microstructure evolution for different post-homogenisation cooling rates and the flow stress behaviour in direct chill cast AA6060 alloys were studied. Results revealed that decreasing cooling rates reduced the flow stress owing to the precipitation of Mg2Si and reduction of the solid solution level. Micro-alloying of Mn generated a distribution of α-Al(FeMn)Si dispersoids during the homogenisation, with the size and number density decreasing at higher homogenisation temperatures. TEM studies confirmed that the dispersoids acted as favourable nucleation sites for Mg2Si and significantly promoted the precipitation of Mg2Si during subsequent cooling. The high-temperature flow stress was controlled by the solid solution levels of Mg, Si, and Mn resulting from the interaction between dispersoids and Mg2Si. The combination of the Mn addition, a low cooling rate, and a low homogenisation temperature provided the lowest flow stress, which improved the hot workability of the alloy and promoted ready dissolution of Mg2Si during extrusion. On a étudié l’évolution de la microstructure pour différentes vitesses de refroidissement post-homogénéisation et le comportement de la contrainte d’écoulement des alliages AA6060 coulés à froid. Les résultats ont révélé que la diminution des vitesses de refroidissement réduisait la contrainte d’écoulement en raison de la précipitation du Mg2Si et de la réduction du niveau de solution solide. Le microalliage de Mn a engendré une distribution de dispersoïdes Al(FeMn)Si-α pendant l’homogénéisation, la taille et la densité numérique diminuant aux températures plus élevées d’homogénéisation. Les études de MET ont confirmé que les dispersoïdes agissaient comme des sites favorables à la nucléation du Mg2Si et favorisaient de manière significative la précipitation du Mg2Si lors du refroidissement subséquent. La contrainte d’écoulement à haute température était contrôlée par les niveaux de solution solide de Mg, Si et Mn résultant de l’interact

This study explored the effects of compositional variation of Al-Cu 206 alloys (Si and Mn concentrations, 0.12 versus 0.3 wt.% each) on the precipitation and thermal stability of h¢ precipitates, and the associated elevated-temperature strengths during long-term thermal exposure at 300 C. The results indicated that both alloys under the T7 condition exhibited comparable yield strengths at 20 and 300 C, which were predominantly controlled by h¢ precipitates. Upon exposure at 300 C for up to 1000 h, the h¢ precipitates in the alloy with low Si and Mn concentrations remained stable and resistant to transformation into the equilibrium h phase. The coarsening of h¢ proceeded through both lengthening and thickening, resulting in the continuing decline in YS at 300 C from 93 MPa after 300 C/100 h to 78 MPa after 300 C/1000 h. Conversely, the h¢ precipitates in the alloy with high Si and Mn concentrations underwent almost complete transformation into deleterious h after only 100 h at 300 C, thus imparting a significantly lower YS of 69 MPa after 300 C/100 h. The possible sources of these microstructure and property changes with the compositional variation were explored. This study has implications for strategic design of Al-Cu alloys for high-temperature applications.

The gSeaGen code is a GENIE-based application developed to efficiently generate high statistics samples of events, induced by neutrino interactions, detectable in a neutrino telescope. The gSeaGen code is able to generate events induced by all neutrino flavours, considering topological differences between track-type and shower-like events. Neutrino interactions are simulated taking into account the density and the composition of the media surrounding the detector. The main features of gSeaGen are presented together with some examples of its application within the KM3NeT project

Heat-treatable cast and wrought aluminum alloys are widely used for structural applications in the automobile and aerospace industries. To assess and diagnose the production and quality problems related to industrial heat treatments, differential scanning calorimetry (DSC) was used as a tool in the present work to determine the thermal histories of samples that had undergone different tempers of three commonly used aluminum alloys, namely a high-pressure die-cast AlSi10Mg0.3Mn alloy, permanent-mold cast Al-Si-Cu 319 alloy, and extruded Al-Mg-Si AA6082 alloy. Various peaks detected in the DSC curves were analyzed and characterized to identify the precipitation/dissolution reactions of metastable phases, aiming to establish a “fingerprint” of each temper of the three experimental alloys. Results showed that both the number and size of exothermic peaks varied with the temper owing to distinct precipitation behaviors, providing an effective means of fingerprinting the various tempers. Meanwhile, electrical conductivity and microhardness data provided the supplementary support for the fingerprinting. The thermal histories of three experimentally heat-treated alloys were well traced and distinguished by the combination of DSC characteristics and electrical conductivity and microhardness results, promoting the DSC application in the quality control and verification of industrial heat treatments. In addition, the microstructures after the various tempers were observed to confirm the evolution of the precipitation reactions revealed in the DSC curves.

Eutectic Al-13%Si alloys are widely used in the automotive industry for manufacturing components, such as pistons and cylinder heads. To reduce greenhouse gas emissions and enhance the engine efficiency, their service temperature keeps increasing to 250-350 °C, leading to the deterioration of their mechanical properties and the creep resistance. In the present work, Mo was further added to Mn-containing Al-13%Si piston alloys aiming at improving the overall properties at elevated temperatures. Compared with the Mn-containing base alloy, Mo further enhanced the precipitation of dispersoids by expanding the dispersoid zone and restricting the dispersoid-free zone after the proper precipitation treatment (520 °C/12 h), resulting in a remarkable improvement in the yield strength at both room temperature and 300 °C, as well as the creep resistance at 300 °C. Furthermore, the beneficial effect of Mo addition on the improved yield strength and creep resistance was especially prominent during long-term thermal exposure (up to 1000 h at 300 °C) due to the synergistic effect of thermally stable dispersoids and the retardation of the gradual fragmentation and spheroidization of Si particles.