180 research outputs found

    Development of multi-criteria decision support system (DSS) coupled with GIS for identifying optimal locations for soil aquifer treatment (SAT) facilities

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    Η διαχείριση του εμπλουτισμού των υδροφορέων αποτελεί μια ευρέως διαδομένη τεχνική, ιδιαίτερα σε υδρολογικά ευαίσθητες περιοχές, όπως αυτές της Μεσογειακής Λεκάνης, όπου οι υδατικοί πόροι είναι περιορισμένοι. Η επιλογή της χωροθέτησης έργων τεχνητού εμπλουτισμού (Τ.Ε.) αποτελεί μια πολύπλοκη διαδικασία το αποτέλεσμα της οποίας καθορίζει εν πολλοίς και την ίδια την αποτελεσματικότητα του έργου. Η εν λόγω διαδικασία περιπλέκεται εντονότερα όταν πρόκειται για τη χρηση νερών εμπλουτιμού υποβαθμισμένης ποιότητας. Βασικός στόχος της παρούσας εργασίας είναι η παρουσίαση ενός πρόδρομου εργαλείου πολυ-κριτιριακού Συστήματος Λήψης Αποφάσεων, το οποίο ενσωματώνει σε μια δυναμική πλατφόρμα: τόσο τις τεχνικές του Τ.Ε. όσο και τα γεωγραφικά χαρακτηριστικά που καθορίζουν την αποτελεσματικότητα του έργου. Το προτεινόμενο σύστημα αποτελεί προχωρημένο εργαλείο σύζευξης Συστημάτων Λήψης Αποφάσεων και Γεωγραφικών Πληροφοριών ικανό να αξιολογεί κρίσιμα ζητήματα που αφορούν σε έργα Τ.Ε. –γεωλογικά, υδρογεωλογικά, κλιματολογικά, νομικά, κοινωνικά, οικονομμικά κ.α. – με ιδιαίτερη έμφαση σε συστήματα Επεξεργασίας-Εδάφους- Υδροφόρου. Το συγκεκριμένο εργαλείο πρόκειται να ενσωματωθεί στο λογισμικό ArcGIS, σε περιβάλλον φιλικό προς το χρήστη, όπου η προβολή και επεξεργασία χωρικών δεδομένων μπορεί να πραγματοποιηθεί με τη χρήση Arc tools.Managed Aquifer Recharge is a wide-spread well-established groundwater engineering method which is largely seen as an alternative potential major source for water and this conclusion becomes even more pronounced in semi-arid and/or arid areas, such as the Mediterranean Basin. The process of site selection for the installation of a MAR facility is of paramount importance for the feasibility and effectiveness of the project itself, especially when the facility will include the use of waters of impaired quality as a recharge source. The main objective of this study is to present the developed framework of a multicriteria Decision Support System (DSS) that integrates within a dynamic platform: the main groundwater engineering parameters associated with MAR applications together with the general geographical features which determine the effectiveness of such a project. The proposed system will provide an advanced coupled DSS-GIS tool capable of handling local MAR-related issues -such as hydrogeology, topography, soil, climate etc., and spatially distributed variables -such as societal, economic, administrative, legislative etc., with special reference to Soil-Aquifer- Treatment technologies. The new SAT-selection tool in question is integrated in ArcGIS software -within a user friendly environment- where data can be processed and displayed using Arc tools for spatial analysis

    Mineralogical Controls on the Ti Isotope Composition of Subduction Zone Magmas

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    The positive Ti isotope versus SiO2-content correlation in igneous rocks reflects the fractional crystallization of Ti-bearing oxide minerals. However, Ti isotope variations of subduction-related igneous rocks indicate that the Ti isotope compositions of their mantle sources are heterogeneous and additional mineral phases may promote Ti isotope fractionation. We have determined the Ti isotope composition of well-characterized subduction-related basalts, andesites and boninites. Samples from the Solomon Islands, the Troodos ophiolite in Cyprus, and Cape Vogel in Papua New Guinea show small but resolvable variations that may be related to differences in their mantle sources. Specifically, the δ49Ti of boninites (+0.109‰ to +0.168‰) is slightly higher than that of tholeiites (−0.027‰ to +0.111‰) from the same localities (Troodos in Cyprus and Cape Vogel in Papua New Guinea). Modeling suggests the partial melting of progressively depleted mantle sources where residual Cr-spinel plays a greater role in controlling the Ti budget during partial melting. More pronounced variations in δ49Ti are clearly linked to the fractional crystallization of Ti-oxides: Samples from Rabaul Volcanic Complex (New Britain, Papua New Guinea) show increasing δ49Ti (up to +0.373‰) with increasing Ti/V and decreasing Dy/Yb. Fractional crystallization models suggest that oxide minerals and amphibole are needed to sufficiently increase the δ49Ti of these magmas. Our study highlights that the combination of diagnostic trace element patterns and Ti isotope compositions in subduction-related igneous rocks can be a powerful tool to constrain petrogenetic processes and to discriminate between different crystallizing mineral phases

    Evaluating intuitiveness of vertical-aware click models

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    Modeling user behavior on a search engine result page is important for understanding the users and supporting simulation experiments. As result pages become more complex, click models evolve as well in order to capture additional aspects of user behavior in response to new forms of result presentation. We propose a method for evaluating the intuitiveness of vertical-aware click models, namely the ability of a click model to capture key aspects of aggregated result pages, such as vertical selection, item selection, result presentation and vertical diversity. This method allows us to isolate model components and therefore gives a multi-faceted view on a model's performance. We argue that our method can be used in conjunction with traditional click model evaluation metrics such as log-likelihood or perplexity. In order to demonstrate the power of our method in situations where result pages can contain more than one type of vertical(e.g., Image and News) we extend the previously studied Federated Click Model such that it models user clicks on such pages. Our evaluation method yields non-trivial yet interpretable conclusions about the intuitiveness of click models, highlighting their strengths and weaknesses

    Heterogeneously catalyzed hydrothermal processing of C5-C6 sugars

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    Biomass has been long exploited as an anthropogenic energy source; however, the 21st century challenges of energy security and climate change are driving resurgence in its utilization both as a renewable alternative to fossil fuels and as a sustainable carbon feedstock for chemicals production. Deconstruction of cellulose and hemicellulose carbohydrate polymers into their constituent C5 and C6 sugars, and subsequent heterogeneously catalyzed transformations, offer the promise of unlocking diverse oxygenates such as furfural, 5-hydroxymethylfurfural, xylitol, sorbitol, mannitol, and gluconic acid as biorefinery platform chemicals. Here, we review recent advances in the design and development of catalysts and processes for C5-C6 sugar reforming into chemical intermediates and products, and highlight the challenges of aqueous phase operation and catalyst evaluation, in addition to process considerations such as solvent and reactor selection

    The Application of Reproductive Technologies to Natural Populations of Red Deer

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    P. 93-102Over the past decade, there has been increasing interest in the application of reproductive technology to the conservation and management of natural populations of deer. The application of assisted reproduction technologies within natural population of deer is in its infancy. However, its future potential is enormous, particularly in relation to genetic management or conservation. This paper reviews the present state of such technologies for a wild subspecies of red deer, the Iberian red deer (Cervus elaphus hispanicus), by discussing the major components of oestrous synchronization, semen collection/cryopreservation and insemination techniques. In addition, findings made during the course of studies on natural populations have enormous potential for the understanding of novel reproductive mechanism that may not be uncovered by livestock or human studies. A summary of these results are also reviewed her

    Continuous evaluation of large-scale information access systems : a case for living labs

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    A/B testing is currently being increasingly adopted for the evaluation of commercial information access systems with a large user base since it provides the advantage of observing the efficiency and effectiveness of information access systems under real conditions. Unfortunately, unless university-based researchers closely collaborate with industry or develop their own infrastructure or user base, they cannot validate their ideas in live settings with real users. Without online testing opportunities open to the research communities, academic researchers are unable to employ online evaluation on a larger scale. This means that they do not get feedback for their ideas and cannot advance their research further. Businesses, on the other hand, miss the opportunity to have higher customer satisfaction due to improved systems. In addition, users miss the chance to benefit from an improved information access system. In this chapter, we introduce two evaluation initiatives at CLEF, NewsREEL and Living Labs for IR (LL4IR), that aim to address this growing “evaluation gap” between academia and industry. We explain the challenges and discuss the experiences organizing these living labs

    Stabilization of mesoporous nanocrystalline zirconia with Laponite

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    The mesoporous nanocrystalline zircoina was synthesized via solid state reaction-structure directing method in the presence of Laponite. The introduction of Laponite renders the higher thermal stability and lamellar track to the zirconia. Laponite acts as inhibitor for crystal growth and also hard template for the mesostructure. The role of Laponite is attributed to the interaction between the zirconia precursors and the nano-platelets of Laponite via the bridge of hydrophilic segments of surfactant. It results in the formation of Zr-O-Mg-O-Si frameworks in the direction of Laponite layer with the condensation of frameworks during the calcination process, which contributes the higher stability and lamellar structure to the nano-sized zirconia samples

    Layer-by-layer deposition of open-pore mesoporous TiO 2- Nafion® film electrodes

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    The formation of variable thickness TiO2 nanoparticle-Nafion® composite films with open pores is demonstrated via a layer-by-layer deposition process. Films of about 6 nm diameter TiO2 nanoparticles grow in the presence of Nafion® by “clustering” of nanoparticles into bigger aggregates, and the resulting hierarchical structure thickens with about 25 nm per deposition cycle. Film growth is characterized by electron microscopy, atomic force microscopy, and quartz crystal microbalance techniques. Simultaneous small-angle X-ray scattering and wide-angle X-ray scattering measurements for films before and after calcination demonstrate the effect of Nafion® binder causing aggregation. Electrochemical methods are employed to characterize the electrical conductivity and diffusivity of charge through the TiO2-Nafion® composite films. Characteristic electrochemical responses are observed for cationic redox systems (diheptylviologen2+/+, Ru(NH3)3+/2+6, and ferrocenylmethyl-trimethylammonium2+/+) immobilized into the TiO2-Nafion® nanocomposite material. Charge conduction is dependent on the type of redox system and is proposed to occur either via direct conduction through the TiO2 backbone (at sufficiently negative potentials) or via redox-center-based diffusion/electron hopping (at more positive potentials)

    The Short-Term Effect of Weight Loss Surgery on Volumetric Breast Density and Fibroglandular Volume

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    Purpose: Obesity and breast density are both associated with an increased risk of breast cancer and are potentially modifiable. Weight loss surgery (WLS) causes a significant reduction in the amount of body fat and a decrease in breast cancer risk. The effect of WLS on breast density and its components has not been documented. Here, we analyze the impact of WLS on volumetric breast density (VBD) and on each of its components (fibroglandular volume and breast volume) by using three-dimensional methods. Materials and Methods: Fibroglandular volume, breast volume, and their ratio, the VBD, were calculated from mammograms before and after WLS by using Volpara™ automated software. Results: For the 80 women included, average body mass index decreased from 46.0 ± 7.22 to 33.7 ± 7.06 kg/m2. Mammograms were performed on average 11.6 ± 9.4 months before and 10.1 ± 7 months after WLS. There was a significant reduction in average breast volume (39.4 % decrease) and average fibroglandular volume (15.5 % decrease), and thus, the average VBD increased from 5.15 to 7.87 % (p < 1 × 10−9) after WLS. When stratified by menopausal status and diabetic status, VBD increased significantly in all groups but only perimenopausal and postmenopausal women and non-diabetics experienced a significant reduction in fibroglandular volume. Conclusions: Breast volume and fibroglandular volume decreased, and VBD increased following WLS, with the most significant change observed in postmenopausal women and non-diabetics. Further studies are warranted to determine how physical and biological alterations in breast density components after WLS may impact breast cancer risk.ECU Open Access Publishing Support Fun
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