481 research outputs found
Optimal resource reallocation can achieve water conservation, emissions reduction, and improve irrigated agricultural systems
No full textAsynchronous meiotic rhythm as the cause of partial chromosome elimination in Paspalum ovale (Gramineae: Paniceae).
No full textFRICTION STIR WELDINGIntroduzione alla tecnologia
No full textLa Friction Stir Welding (FSW) è una tecnologia di saldatura relativamente nuova: è stata inventata dal The Welding Institute (TWI), l’Istituto della Saldatura Inglese, che l’ha brevettata nel dicembre del 1991. Questo nuovo processo, particolarmente adatto per realizzare giunzioni di pezzi in leghe d’alluminio, è stato accolto con grande interesse dal mondo industriale ed in pochi anni ha avuto un enorme sviluppo, soprattutto nelle applicazioni navali ma anche nell’industria aerospaziale, ferroviaria ed automobilistica
Development of a behaviour-pattern based global sensitivity analysis procedure for coupled socioeconomic and environmental models
No full textDynamically Coupled Socioeconomic system dynamics models integrated with physically-based Environmental Models (DCSEM) can capture relationships between complex environmental and socioeconomic systems, and are promising tools for participatory environmental management involving the integration of various viewpoints, disciplines and processes for sustainable water resources management. However, the application of DCSEMs has been limited for many reasons, including the complexity of the model coupling process (i.e., the lack of a flexible model coupling approach), issues of over-parameterization, high parameter uncertainty, intensive computational requirements (due to many interacting parameters), and the possibility of eliciting behaviour-pattern oriented model outputs. As such, most conventional (numerical) procedures for model evaluation (i.e., analysis of point values of modelled results) that have been implemented for physically-based models are not applicable to DCSEMs. In order to address these challenges, this study developed a novel automatic behaviour-pattern global sensitivity analysis (GSA) procedure to determine the influence of input parameters on the general behaviour trends (rather than numerical point values) of coupled model outputs. The developed behaviour-pattern GSA procedure was implemented in an existing software (Tinamït), developed previously by the authors, to ensure ease-of-use. This study investigates the suitability of the proposed behaviour-pattern GSA procedure for the analysis of DCSEMs by comparing the proposed procedure with the conventional numerical procedure. The numerical and proposed behaviour-pattern procedures, coupled with the Morris (qualitative) and EFAST (quantitative) GSA methods, were applied to a DCSEM to rank and screen parameters in a water table depth simulation in Pakistan. The determination of important parameters facilitates subsequent model calibration and groundwater management. It was found that the Morris and EFAST methods achieved similar parameter ranking results in the numerical and behavioural procedures, respectively. The results also indicated that the behaviour-pattern GSA procedure offers more information about several important parameters, and a variety of parameter ranking orders, compared to the numerical GSA procedure, regardless of which GSA method (Morris or EFAST) was used. The increased information obtained through the application of the developed behaviour-pattern procedure confirms that the DCSEM model outputs are behaviour-oriented. It is recommended that the proposed behaviour-pattern GSA procedure be used with the Morris method, which has a higher computational efficiency (>150 times) than the EFAST method, to detect important parameters in DCSEMs
Analisys of FSW welds made of aluminium alloy AW6082-T6
No full textPurpose of this paper is to analyze the results of tests on the mechanical properties and microstructural changes in Friction Stir Welds in the aluminium alloy 6082-T6 in function of varying process parameters.
Design/methodology/approach: the produced tensile strength of the produced welds was measured and the correlation with process parameter was assessed. The welds’ microstructure in various zones was analyzed using an optical microscope. Microhardness measurements were performed on the welds’ cross-sections. Findings a tendency was observed of the mechanical resistance of test welds to increased with the increase of travel (welding) speed, maintaining constant rotational speed. Hardness decrease was observed in weld nugget and heat affected zone, of entity inferior that that of fusion welds. Origins of tunnel (worm hole) defects were found and analyzed.
Research limitations/implications: various combinations of process parameters were used to produce the test welds, but without the possibility of controlling the downward force. Further extension of applicable parameters combinations should be examined.
Practical implications: the increase of mechanical resistance with increasing welding speed offers an immediate economic return, as the process efficiency is increased.
Originality/value: information contained herein can be useful to further investigate on the possibility of improving the properties of FSW welds, as well as the efficiency of the process
Summary of the Second Workshop on Liquid Argon Time Projection Chamber Research and Development in the United States
No full textThe second workshop to discuss the development of liquid argon time projection chambers (LArTPCs) in the United States was held at Fermilab on July 8-9, 2014. The workshop was organized under the auspices of the Coordinating Panel for Advanced Detectors, a body that was initiated by the American Physical Society Division of Particles and Fields. All presentations at the workshop were made in six topical plenary sessions: i) Argon Purity and Cryogenics, ii) TPC and High Voltage, iii) Electronics, Data Acquisition and Triggering, iv) Scintillation Light Detection, v) Calibration and Test Beams, and vi) Software. This document summarizes the current efforts in each of these areas. It primarily focuses on the work in the US, but also highlights work done elsewhere in the world
Development of a behaviour pattern-based testing approach for coupled socioeconomic and environmental models
No full textUnderstanding the interactions between human and environmental systems is key to sustainable environmental management. Dynamically Coupled Socioeconomic system dynamics models integrated with physically-based Environmental Models (DCSEMs) are promising tools to appropriately capture the non-linear relationships be-tween complex socioeconomic and biophysical systems, thereby supporting sustainable environmental man-agement. However, existing approaches for testing integrated models are commonly based on the point-to-point analysis of model outputs, which is not suitable for DCSEMs that are behaviour pattern oriented. Consequently, the lack of well-defined behaviour pattern-based approaches has limited the adaptability of DCSEMs. To address this gap, this study proposes a novel behaviour pattern-based model testing approach that includes global sensitivity analysis (GSA), auto-calibration algorithms, and evaluation to assess behaviour pattern similarities between model outputs and real-world trends. The proposed approach is demonstrated through a real-world case study, in which an existing DCSEM is calibrated and evaluated to simulate water table depth in the Rechna Doab region of Pakistan. Compared to the conventional numerical point approach, the proposed approach is better suited for DCSEMs, as it replicates observed system behaviour patterns (as opposed to observed point values) over time. Furthermore, the outcomes of the Theil inequality statistical analysis and parameter distribution analysis provide evidence that the suggested approach is effective in testing and improving the performance of the DCSEM by capturing the spatial heterogeneity within the study area. The proposed behaviour-pattern testing procedure is a useful approach for model testing in data-limited, spatially-distributed DCSEMs
Similar hats on similar heads: uniformity and alienation at the Rat Pack’s Summit Conference of Cool
No full textThis article considers the nightclub shows of the Rat Pack, focussing particularly on the Summit performances at the Sands Hotel, Las Vegas, in 1960. Featuring Frank Sinatra, Dean Martin, Sammy Davis Jr, Peter Lawford and Joey Bishop, these shows encompassed musical, comic and dance routines, drawing on the experiences each member had in live vaudeville performance. The discussion outlines these individual histories, and draws attention to a shared fascination with impersonation, which forms an explicit and implicit part of the act, as the performers’ stage personas are already emulatory. In addition to the influence of vaudeville, the construction of the Rat Pack also draws on the structures of blackface minstrelsy, with the interactions of the five members being patterned on a fluid variant of the interlocutor-endmen relationships. The interweaving of these influences and performance styles underpins a dominant concern of the troupe, as the comic material frequently negotiates the racial, national and religious identities of the individual performers. In particular, this deals with their shared status of having immigrant ancestry, a status which I term as being ‘hyphenated-American’, suspended between historical, public and aspirational identities
Large scale flood risk mapping in data scarce environments: An application for Romania
No full textLarge-scale flood risk assessment is essential in supporting national and global policies, emergency operations and land-use management. The present study proposes a cost-efficient method for the large-scale mapping of direct economic flood damage in data-scarce environments. The proposed framework consists of three main stages: (i) deriving a water depth map through a geomorphic method based on a supervised linear binary classification; (ii) generating an exposure land-use map developed from multi-spectral Landsat 8 satellite images using a machine-learning classification algorithm; and (iii) performing a flood damage assessment using a GIS tool, based on the vulnerability (depth-damage) curves method. The proposed integrated method was applied over the entire country of Romania (including minor order basins) for a 100-year return time at 30-m resolution. The results showed how the description of flood risk may especially benefit from the ability of the proposed cost-efficient model to carry out large-scale analyses in data-scarce environments. This approach may help in performing and updating risk assessments and management, taking into account the temporal and spatial changes in hazard, exposure, and vulnerability
Large scale flood risk mapping in data scarce environments : An application for Romania
No full textLarge-scale flood risk assessment is essential in supporting national and global policies, emergency operations and land-use management. The present study proposes a cost-efficient method for the large-scale mapping of direct economic flood damage in data-scarce environments. The proposed framework consists of three main stages: (i) deriving a water depth map through a geomorphic method based on a supervised linear binary classification; (ii) generating an exposure land-use map developed from multi-spectral Landsat 8 satellite images using a machine-learning classification algorithm; and (iii) performing a flood damage assessment using a GIS tool, based on the vulnerability (depth-damage) curves method. The proposed integrated method was applied over the entire country of Romania (including minor order basins) for a 100-year return time at 30-m resolution. The results showed how the description of flood risk may especially benefit from the ability of the proposed cost-efficient model to carry out large-scale analyses in data-scarce environments. This approach may help in performing and updating risk assessments and management, taking into account the temporal and spatial changes in hazard, exposure, and vulnerability.
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