Collaborative OLAP with Tag Clouds: Web 2.0 OLAP Formalism and Experimental Evaluation

Increasingly, business projects are ephemeral. New Business Intelligence tools must support ad-lib data sources and quick perusal. Meanwhile, tag clouds are a popular community-driven visualization technique. Hence, we investigate tag-cloud views with support for OLAP operations such as roll-ups, slices, dices, clustering, and drill-downs. As a case study, we implemented an application where users can upload data and immediately navigate through its ad hoc dimensions. To support social networking, views can be easily shared and embedded in other Web sites. Algorithmically, our tag-cloud views are approximate range top-k queries over spontaneous data cubes. We present experimental evidence that iceberg cuboids provide adequate online approximations. We benchmark several browser-oblivious tag-cloud layout optimizations.Comment: Software at https://github.com/lemire/OLAPTagClou

Roaring bitmap : nouveau modèle de compression bitmap

Les index bitmap sont très utilisés dans les entrepôts de données et moteurs de recherche. Leur capacité à exécuter efficacement des opérations binaires entre bitmaps améliore significativement les temps de réponse des requêtes. Cependant, sur des attributs de hautes cardinalités, ils consomment un espace mémoire important. Ainsi, plusieurs techniques de compression bitmap ont été introduites pour réduire l'espace mémoire occupé par ces index, et accélérer leurs temps de traitement. Ce papier introduit un nouveau modèle de compression bitmap, appelé Roaring bitmap. Une comparaison expérimentale, sur des données réelles et synthétiques, avec deux autres solutions de compression bitmap connues dans la littérature : WAH (Word Aligned Hybrid compression scheme) et Concise (Compressed "n" Composable integer Set), a montré que Roaring bitmap n'utilise que 25% d'espace mémoire comparé à WAH et 50% par rapport à Concise, tout en accélérant significativement les temps de calcul des opérations logiques entre bitmaps (jusqu'à 1100 fois pour les intersections)

Collaborative OLAP with Tag Clouds: Web 2.0 OLAP Formalism and Experimental Evaluation

Increasingly, business projects are ephemeral. New Business Intelligence tools must support ad-lib data sources and quick perusal. Meanwhile, tag clouds are a popular community-driven visualization technique. Hence, we investigate tag-cloud views with support for OLAP operations such as roll-ups, slices, dices, clustering, and drill-downs. As a case study, we implemented an application where users can upload data and immediately navigate through its ad hoc dimensions. To support social networking, views can be easily shared and embedded in other Web sites. Algorithmically, our tag-cloud views are approximate range top-k queries over spontaneous data cubes. We present experimental evidence that iceberg cuboids provide adequate online approximations. We benchmark several browser-oblivious tag-cloud layout optimizations

Collaborative OLAP with Tag Clouds: Web 2.0 OLAP Formalism and Experimental Evaluation

Increasingly, business projects are ephemeral. New Business Intelligence tools must support ad-lib data sources and quick perusal. Meanwhile, tag clouds are a popular community-driven visualization technique. Hence, we investigate tag-cloud views with support for OLAP operations such as roll-ups, slices, dices, clustering, and drill-downs. As a case study, we implemented an application where users can upload data and immediately navigate through its ad hoc dimensions. To support social networking, views can be easily shared and embedded in other Web sites. Algorithmically, our tag-cloud views are approximate range top-k queries over spontaneous data cubes. We present experimental evidence that iceberg cuboids provide adequate online approximations. We benchmark several browser-oblivious tag-cloud layout optimizations

Development of an Analytical Model for a Fiber Optic Evanescent Wave Sensor

Spectroscopy in the near infrared range is a powerful tool for the qualitative and quantitative analysis of a variety of materials in the gas liquid or solid phases. The use of optical fibers as a means of performing cost effective in-situ spectroscopic analysis has gained a lot of attention in many fields in the past three decades. Intensity based fiber optic sensors, which rely on variations in transmission power at a fixed wavelength for the characterization of material, are relatively inexpensive to fabricate and provide an easy to read signal. The objective of this thesis will be to present an analytical model developed for a multimode fiber optic evanescent wave sensor (FOEWS) capable of monitoring the charge cycle of a lithium-ion battery cell. The sensor is fabricated by partial removal of the cladding material surrounding the core of a multimode fiber optic. The thinned cladding section allows for transmission loss via evanescing waves which radiate power out from the core as a function of the external environment. In contrast to FOEWS designs which use a single mode optical fiber, the use of a multimode fiber causes difficulty in numerical modeling of the system. Single mode optical fibers have core diameters which are small relative to the wavelength of light propagating within. As such, solving for the transmission response of a single mode fiber can be accomplished using a numerical solver. By using a multimode optical fiber the fiber core diameter is orders of magnitude larger than the wavelength of propagating light. Attempting to accurately mesh a multimode optical fiber requires an unmanageably large mesh which cannot be solved in a reasonable time frame. Alternative approaches for the modeling of a multimode FOEWS have been proposed in the past. However, these methods make use of effective attenuation coefficients to estimate the transmission coefficient of the sensor and thus, they do not include a direct analysis of the electromagnetic field solutions of the thin cladding region. An analytical method for accurately solving the attenuation coefficient using the transfer matrix method is presented. Adoption of the analytical method extends the theoretical description of FOEWS model allowing for more accurate prediction of the sensor behavior by directly accounting for cladding thickness without the use of empirically determined attenuation coefficients. FOEWS fabricated using commercially available step index multimode fibers etched with buffered hydrofluoric acid were used to verify predictions of the newly modified model. Model predictions are matched with experimental tests performed using known index of refraction samples of glycerol and calibrated thermal optic oil ranging from 1.451 to 1.466. The experimentally observed intensity variations are compared to model predictions for verification. The fabricated FOEWS was determined to have a cladding thickness of 0.485±0.1 µm. Comparison with direct measurement under scanning electron microscope (SEM) place the variations of the model from the experimental results within one standard deviation of the fabrication tolerances of the optical fiber. Building on the increased capabilities of the transfer matrix method to analytically model the thin film reflection coefficient, a method is put forth to simulate the partial contact of a solid analyte with a FOEWS. A case study is presented which investigates the FOEWS response behavior to a solid lithium-ion graphite anode held in partial contact to the fiber. SEM images of lithium-ion anode materials held in sensing contact with a fabricated FOEWS are analyzed to determine the fractional contact area of the fiber optic sensing region with the solid anode. A statistical average of the fractional contact area as well as mean depth of non-contact regions is determined. The presence of partial contact between the fiber thin cladding and anode material creates a fourth thin film region which is filled with electrolyte liquid from the cell. The addition of a fourth thin film region is added to the transfer matrix method analysis of the sensing region of the FOEWS to account for the presence of liquid electrolyte between the fiber sensing region and anode bed. By splitting the model analysis of the sensing region into two separate sections representing the fractional full and fractional partial contact regions effects of partial is then studied using simulated results. In summary, the ability to directly model thin film cladding effects using the transfer matrix method has been added to pre-existing FOEWS models. This new functionality is tested against fabricated devices using solutions of various index of refraction. The model is then used to predict the effect of partial contact of the sensor with a solid anode analyte from a lithium-ion cell

Pulp and paper mill bacteria as a potential source of novel encapsulation materials / by Peter R. Godin.

"A total of 194 bacteria were isolated from pulp and paper biofilms from a mill in Thunder Bay, Canada. Diversity of the 194 bacteria indicated that the amounts of bacteria found in these biofilms may be influenced by seasonal factors. From this stock of 194 bacteria, 55 isolates were preliminarily screened for their carbohydrate quantity and flocculation ability with hopes of identifying isolates that may be capable of producing an extracellular polymeric substance that could be used as a novel encapsulation material. Four isolates, 1, 2, 8, and 34 were selected from the carbohydrate screening and they were identified as a Flavobacterium sp. (isolate 1), Pseudomonas sp. (isolate 2), and a Sphingomonas sp. (isolate 34). Unfortunately, isolate 8 identity could not be confirmed using 16s rDNA sequencing and biochemical testing. Isolates 1 and 34 carbohydrate was harvested and lyophilized in attempts to create gels. Following gelation experiments using different concentrations of bacterial carbohydrate along with cation addition to the solution, it was observed that isolate 1 carbohydrate produced semi-solid gels at 2.0 and 1.0% w/v concentrations when FeC1 3 was added. Both isolate 1 and 34 carbohydrates appeared to enhance gelation of non-gelling concentrations of the known polysaccharides Gellan and Xanthan when mixed gel experiments were conducted. "--Abstrac

Coordinating rooks and bishops: an institutional history of the joint army and navy board, 1903-1919

This thesis examines the formative years of the Joint Army and Navy Board, 1903 to 1919. It serves as an institutional history, focusing on the function of the interservice coordination body. The Joint Board is examined within the context of formulating American military strategy and U.S. diplomatic affairs from its creation in July 1903 to its reconstitution in 1919. At present no comprehensive historical study exists focusing on the Joint Board. Currently, interservice cooperation and coordination during this period receive no more than peripheral analysis in war plan studies. Thus, this work begins the first comprehensive history of the precursor to the Joint Chiefs of Staff. This thesis analyzes the origins and creation of the Joint Board, the Board??s basic duties and responsibilities, and Joint Board actions as they impacted U.S. diplomacy and military strategy concerning the homeland and coast defense, the Caribbean and Cuba, the Panama Canal, as well as the Pacific and the Philippines. Within this geographical framework, this thesis explores the relation of the Joint Board to the Navy General Board and Army General Staff, the cooperation of the U.S. Army and U.S. Navy between the Spanish-American War and World War I, the impact of Joint Board actions on American civil-military relations, and the efficacy of interservice cooperation. This thesis is based largely on unpublished as well as published primary sources, including the records of the Joint Board, Navy General Board records, Army War College Division records, and members?? personal papers housed at the Library of Congress in Washington, D.C. In addition, secondary sources are used to place the Joint Board within the larger contextual framework of interservice cooperation, U.S. civil-military relations, and American military history during the early twentieth century

Classification and automatic indexing in a persistent object environment

The goal of this project is to study classification and automatic indexing for multimedia data in the context of digital libraries. The general objectives are: (1) to propose methods for digital media classification and indexing and (2) to implement them effectively by using a persistent environment provided by object-oriented database systems

Polymer Photoelectrodes for Solar Fuel Production: Progress and Challenges

Converting solar energy to fuels has attracted substantial interest over the past decades because it has the potential to sustainably meet the increasing global energy demand. However, achieving this potential requires significant technological advances. Polymer photoelectrodes are composed of earth-abundant elements, e.g. carbon, nitrogen, oxygen, hydrogen, which promise to be more economically sustainable than their inorganic counterparts. Furthermore, the electronic structure of polymer photoelectrodes can be more easily tuned to fit the solar spectrum than inorganic counterparts, promising a feasible practical application. As a fast-moving area, in particular, over the past ten years, we have witnessed an explosion of reports on polymer materials, including photoelectrodes, cocatalysts, device architectures, and fundamental understanding experimentally and theoretically, all of which have been detailed in this review. Furthermore, the prospects of this field are discussed to highlight the future development of polymer photoelectrodes