189 research outputs found
Virender Sehwag and Cricket’s Existential Anxiety
No full textThe article is in the nature of a personal interpretation of the illustrious career of former Indian batsman Virender Sehwag. Known for his swashbuckling stroke play, he found his niche at the top of the famed Test batting line up that once boasted of the likes of Rahul Dravid, Sachin Tendulkar, V.V.S. Laxman and Saurav Ganguly, despite unanimous opinion of critics about the glaring deficiencies in his batting technique. His rather inconsistent returns in limited overs cricket run counter to the conventional wisdom that associates the ‘copybook style’ of batting with greater successes in the longest format of the sport. The article is less of an attempt to a statistical analysis of the batsman for reaching a quantitative explanation for the said ‘anomaly’ in his performances, and more of an enquiry into his ‘inner world’ as a batsman, offering a metaphorical insight into the existential dichotomy of the longer and shorter formats of cricket. The author draws from the perspective of Danish theologian Soren Kierkegaard on anxiety and that of American anthropologist Ernest Becker on neurosis, reflecting on the various manifestations of despair that haunt batsmen across formats, as a window to Sehwag’s unique defences in dealing with the anxieties at the batting crease. In this quest, the author expresses concerns about the future of the game in the backdrop of the slippery slope of the age-old existential dilemma facing the governing body of the sport in its bid to go truly global
Instrumental approach toward understanding nano-pollutants
No full textNano-pollutants (NPLTs) have recently raised global concerns due to their possible harmful impact on environment and human health. However, until date, information on the occurrence, fate and toxicity of NPLTs in environment is scant. The knowledge gap can be attributed to the lack of advanced and sophisticated methodologies for the precise detection and characterization of NPLTs at lower concentration in complex matrices, such as surface water, wastewater, soil and food. This review briefly discusses the performance of classical methods for characterization and study of the properties of NPLTs. The important properties include shape, size, aggregation state, chemical composition and structure. Chromatographic, microscopic and spectroscopic techniques have been developed for detection and quantitative estimation of fabricated or naturally existed NPLTs in different matrices. Often, combination of these techniques is required for the separation, purification and accurate estimation. For better detection and understanding of the initial steps of interaction with the environmental matrices, pollution sources, such as wastewater and industrial discharges, must be selected as sampling points. Understanding the dynamics of agglomeration, and decantation will allow to estimate the plume of transport to delimit the potential effects.Fil: Naghdi, Mitra. Inrs- Centre Eau, Terre &,Université du Québec; CanadáFil: Metahni, Sabrine. Inrs- Centre Eau, Terre &,Université du Québec; CanadáFil: Ouarda, Yassine. Inrs- Centre Eau, Terre &,Université du Québec; CanadáFil: Brar, Satinder Kaur. Inrs- Centre Eau, Terre &,Université du Québec; CanadáFil: Das, Ratul Kumar. Inrs- Centre Eau, Terre &,Université du Québec; CanadáFil: Cledón, Maximiliano. Institut National de la Recherche Scientifique; Canadá. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina. Universidad Nacional del Comahue- Prov de Rio Negro- Conicet; Argentin
Experimental studies on creping and its influence on mechanical properties of tissue paper products
No full textTissue papers are softer, stretchier, and more water absorbent than regular writing or packaging paper products. Creping of an adhesively bonded low-density paper web from the surface of a rotating Yankee drum is the key manufacturing technique in tissue production. Creping dedensifies and weakens the paper by partially damaging the fibers and the inter-fiber bonds in the fiber network. The process also imparts a signature microstructure, called crepe structure, to the tissue paper. Tissues thus produced have a high specific volume (bulk to basis weight ratio), work to rupture, failure strain (stretch), softness and absorbency. Mechanical properties of tissues are governed by the creping process. Therefore, a scientific understanding of the creping process, and its impact on the structural and mechanical properties of the tissue paper is important.
The present research approaches the highly complex problem from an experimental perspective, with a view to complement ongoing physics based numerical models to simulate creping. Experimental techniques are developed to visualize the high speed creping process, quantify the crepe structure, and finally understand the influence of the crepe structure on the uni-axial tensile response of the tissue. A novel surface imaging based structural quantification technique is developed and successfully demonstrated on a commercial tissue machine. The surface image based quantification technique is also validated by micrographic observations of the tissue cross section under a Scanning Electron Microscope (SEM). This work lays the foundational techniques and protocols for future studies in the laboratory and opens the opportunity to observe crepe structure in real time for quality and process control.
The surface imaging techniques are then used to observe the evolution of the creping microstructure under a tensile load. Local two dimensional strain fields are quantified using Digital Image Correlation (DIC) to gain insight into failure mechanisms at the macroscopic network level. Micro tensile tests are conducted under SEM to gain further insight into the deformation and failure mechanisms operative at fiber length scales. The studies showed the impact of the creping structure, formation, and inter fiber bonds on the tensile response of the tissue paper, specifically along machine direction.Applied Science, Faculty ofMechanical Engineering, Department ofGraduat
Despiking of Turbulent Flow Data in Gravel Bed Stream
No full textThe present experimental study insights the decontamination of instantaneous velocity fluctuations captured by Acoustic Doppler Velocimeter (ADV) in gravel-bed streams to ascertain near-bed turbulence for low Reynolds number. The interference between incidental and reflected pulses produce spikes in the ADV data especially in the near-bed flow zone and therefore filtering the data are very essential. Nortek’s Vectrino four-receiver ADV probe was used to capture the instantaneous three-dimensional velocity fluctuations over a non-cohesive bed. A spike removal algorithm based on the acceleration threshold method was applied to note the bed roughness and its influence on velocity fluctuations and velocity power spectra in the carrier fluid. The velocity power spectra of despiked signals with a best combination of velocity threshold (VT) and acceleration threshold (AT) are proposed which ascertained velocity power spectra a satisfactory fit with the Kolmogorov “–5/3 scaling-law” in the inertial sub-range. Also, velocity distributions below the roughness crest level fairly follows a third-degree polynomial series
Topologies, Modeling, and Control of Hybrid Switched-Capacitor Converters
No full textThis dissertation explored the ideas and concepts for hybrid switched capacitor converter topologies and new power delivery architectures to provide viable solutions for high conversion ratio DC-DC and AC-DC applications. A new Multi Inductor Hybrid (MIH) Converter family for high conversion ratio DC-DC applications has been synthesized and analyzed to provide non-isolated DC-DC conversions with large voltage conversion ratios efficiently. The highlight of this converter family is a 6-level 6-phase 6-inductor MPMIH converter, which achieved 90.7% peak efficiency with a load range of 0-220A at 1V and 1kA/in^3 density.A new modeling method reveals that all odd-level Flying Capacitor Multi-Level converters become current sources with non-ideal timing while the even-level converters stay as voltage sources. A method for identifying unbalanced hybrid converters is also provided.This dissertation demonstrates a two-stage power delivery architecture to bridge AC distribution voltages to core levels for computing loads in data centers. In combination, direct conversion from \textasciitilde110 VAC to 1VDC achieves a peak efficiency of 84.1% while providing output currents up to 160A. Partial power processing for AC/DC applications has been explored with a switched-capacitor (SC) based hybrid step-down converter and its new control techniques. The operation with multiple modules is verified with a 115VAC-to-48VDC conversion and 200VAC input to two 48VDC outputs.A new modular isolated DC-DC converter is proposed and demonstrated for point-pf-load (POL) applications with partial power processing. A prototype of the modular architecture has been demonstrated for a 100V-to-3V point-of-load conversion with a maximum load of 60A. The peak efficiency of 91% is achieved at 57W/20A output. A new multi-inductor multi-output hybrid converter is also proposed and demonstrated. The MiMoH converter prototype has been implemented to demonstrate conversion from a 24-48V input voltage to three individually regulated outputs ranging from 1.2V to 2.2V. The converter prototype achieves 40W peak power and 91.8% peak efficiency. The topologies presented in this dissertation, corroborated with control and modeling techniques, demonstrated superior performance, natural balancing ability, and relatively easy controllability, making them excellent candidates for more compact and efficient system design
Digital privacy:GDPR and its lessons for Australia
No full textAustralia's Privacy Act 1988 is under review with a view to bringing Australia's privacy laws into the digital era, more in line with the European Union's General Data Protection Regulation (GDPR). This article discusses how the GDPR can be refined and standardised to be more effective in protecting privacy in the digital era while not adversely affecting the digital economy that relies heavily on data. We argue that an ideal data policy should be informative and transparent about potential privacy costs while giving consumers a menu of opt-in choices into which they can self-select.</p
When to seek expert advice? A simple model of borrowers with limited liability
No full textWe model the situation where a borrower can choose to acquire costly information about the outcome before implementing a risky project. The borrower is resource-constrained and faces a trade-off between incurring the cost of information or putting effort into the project. We provide novel insights about the type of project the borrower chooses and identify the conditions under which the borrower acquires information. We characterize the optimality conditions for the interest rate charged by a socially-motivated as well as a profit-motivated lender. We find that if the interest rate is high, the borrower is likely to choose riskier projects and acquire information about the outcome. If capital is moderately expensive for the lender, even the socially-motivated lender charges a higher interest and makes a positive profit. This provides an alternate explanation for the prevalence of high-interest rates in the rural credit market, despite the presence of socially-motivated lenders
Production accrue d'acide fumarique par fermentation de déchets agro-industriels.
No full textLa transcription des symboles et des caractères spéciaux utilisés dans la version originale de
ce résumé n’a pas été possible en raison de limitations techniques. La version correcte de ce
résumé peut être lue en PDF. L'acide fumarique (AF) a été identifié comme étant l'un des dix meilleurs produits chimiques de construction modulaire qui peut être produit par fermentation submergée et par fermentation à l'état solide à partir de différents déchets de organiques (la plupart d'origine agro-industrielle). Il a été établi que le coût du substrat (presque 40-60% du coût total) est la principale contribution économique au coût total de production dans la fermentation du AF. Normalement, l’AF est produit commercialement à partir de l'anhydride maléique. Toutefois, en raison de la hausse du prix de l'anhydride maléique (60-70% du coût total de production), les chercheurs ont semblé être plutôt en AFveur d'une production biologique (fermentation) du AF. Comparée à celle des autres champignons filamenteux, la souche Rhizopus oryzae 1526 (famille: Mucoraceae) est utilisée comme principal producteur de AF en raison de ses faibles besoins nutritionnels. Dans l'étude de la production d’AF par la technique d'immobilisation, les coûts des matériaux de support d'immobilisation peuvent représenter de 60 à 70% du coût total du processus et donc l'utilisation de matériaux compatibles de faible coût pour des applications peut être une très bonne option à envisager. Dans les études portant sur la production d’AF par fermentation, le CaCO3 est utilisé pour maintenir un pH proche de la neutralité (6.0) pour favoriser une production maximale d’AF. Une source rentable et durable de CaCO3 peut être une option efficace. De plus, l'utilisation de nanoparticules de CaCO3 et d'irradiation par micro-ondes (en anglais: MWI) permet de réduire la viscosité du milieu de culture et le temps de récupération du AF. La détermination spectrophotométrique du AF dans un échantillon de bouillon fermenté n'est pas une approche méthodologique courante. Ainsi, le développement d'une méthode spectrophotométrique simple et rapide pour l'estimation de la production d’AF dans des échantillons de bouillons fermentés peut être une option intéressante à envisager.
Dans cette étude, une procédure colorimétrique rapide et efficace a été développée pour la quantification du AF présent dans les échantillons de bouillon fermenté. Différents déchets agro-industriels, à savoir les eaux usées de brasserie (en anglais: BW) et les boues d'ultrafiltration de jus de pomme (en anglais: APS), les déchets solides de jus de pomme mélangés aux pelures de riz (en anglais: AP) et des déchets solides de pâtes et papiers (en anglais: PPSW), ont été testés et optimisés pour améliorer la production de AF par fermentation en utilisant le R. oryzae 1526 (R. oryzae). Une stratégie d'immobilisation rentable a été adoptée pour une production accrue d’AF. L'impact des différentes concentrations de micro et de nanoparticules de ZnO, Fe3O4 et MnO2 sur la production d’AF a également été étudié. Enfin, l'application des nanoparticules de carbonate de calcium (en anglais: CCNPs) et l'irradiation par micro-ondes (en anglais: MWI) ont été étudiées dans la production et la récupération du AF, respectivement.
Pour les BW, en utlisant les les conditions optimales de croissance (pH 6, 25 °C, agitation à 200 rpm, 5% (v/v) d'inoculum, 25 g/L concentration en matières solides totales de 25 g/L, et un diamètre de granule de 0,47 ± 0,04 mm), la concentration la plus élevée de AF atteinte a été de 31,3 ± 2,8 g/L.
Dans l'étude de l'immobilisation sur un chiffon de mousseline (en anglais: MC), les niveaux de production et la productivité volumétrique de AF ont été nettement augmentés, passant de 30,56 ± 1,40 g/L à 43,67 ± 0,32 g/L et 0.424 g/(L h) à 1.21 g/(L,h), comparativement à la fermentation acellulaire. Dans une autre étude comprenant les déchets de coquilles d'oeufs de poule (en anglais: EGS), les biofilms (formés sur les EGS) obtenus par fermentation submergée ont nettement amélioré la production et la productivité volumétrique de l'acide fumarique de 30,23 ± 1,23 g/L à 47,22 ± 0,77 g/L et de 0.419/(L,h) à 1.657 g/(L,h), respectivement par rapport aux cellules libres. Les EGS servent également de source de CaCO3.
L'étude comprenant les PPSW a entraîné de bons taux de production de AF par fermentation submergée et par fermentation à l'état solide avec différentes gammes de taille de particules (1,7 mm < x ≤ 3,35 mm, 850 μm < x ≤ 1,7 mm, 300 μm < x ≤ 850 μm, 75 μm < x ≤ 300 μm et 33 μm < x ≤ 75 μm). Dans la fermentation submergée, un maximum de 23,47 ± 0,70 g/L de AF a été obtenu avec une taille de particules de 33 μm < x ≤ 75 μm. La fermentation à l'état solide avec une taille de particules de 75 μm <
x ≤ 300 μm a abouti à une plus forte production de AF (41.45 g/kg de poids sec de PPSW) après 21 jours.
Pour l'étude de la fermentation submergée avec les APSU, les paramètres optimaux pour la production de AF (25,2 ± 1,0 g/L, 0,350 g/(L,h)) soit une concentration de 40 g/L en solides totaux de APSU, un pH de 6,0, une température de 30 °C, agitation à 200 rpm et un temps d'incubation de 72h. La fermentation à l'état solide a permis une production de 52 ± 3 g d’AF par kg en poids sec d’AP avec les conditions optimisées.
Les expériences réalisées avec les AP dans le fermenteur à tambour rotatif à l'état solide à l'échelle laboratoire ont abouti à une concentration d’AF de 138 ± 9 g par kg de poids sec d’AP selon les conditions optimisées. La teneur totale en phénol des AP a considérablement augmenté, passant de 185 ± 10.5 à 345 ± 8.5 mg/g de lyophilisat.
L'étude de l'impact des différentes concentrations (200-1000 μg/ml) de micro- et de nanoparticules de ZnO, Fe3O4 et MnO2 sur la production d’AF a montré que les micro et les nanoparticules de Fe3O4 sont les particules les plus biocompatibles avec le champignon R.oryzae.
L’application de CCNPs a permis a réduit le temps de neutralisation du AF d'environ 160 secondes. De plus, les CCNPs ont amélioré la productivité volumétrique de AF, qui est
passée de 0,47 g/(L,h) à 0,74 g/(L,h). Les viscosités des CCNPs se sont avérées être inférieures à celles des microparticules de carbonate de calcium (en anglais: CCMPs). Une période de chauffage de 10 ± 1 min par MWI a été jugée suffisant pour la récupération d’AF et ce temps est beaucoup plus faible que le temps de chauffage classique de 28 ± 1 min. The symbols and special characters used in the original abstract could not be transcribed due
to technical problems. Please use the PDF version to read the abstract. Fumaric acid (FA) has been identified as one of the top ten building block chemicals that can be produced by submerged and solid state fermentation from different waste materials (mostly of agro-industrial origin). It has been established that substrate cost (almost 40-60% of the total cost) is the major economic input to the total production cost in FA fermentation. Normally, FA is solely being produced commercially from maleic anhydride. However, due to the rising price of maleic anhydride (60-70% of the total production cost), fermentation route is being preferred. Owing to its low nutritional requirements, Rhizopus oryzae 1526 (family: Mucoraceae) strain is used as the main producer of FA. In the immobilization based FA production study, the immobilization support material costs can range from 60-70% of the total process cost and thus exploration of low cost and compatible materials can be a very good option. In the fermentation based FA production studies, CaCO3 is used to maintain a pH around neutral (6.0) for maximum FA production. A cheap and sustainable source of CaCO3 can be an effective option. Moreover, applications of CaCO3 nanoparticles and microwave irradiation (MWI) can reduce the broth viscosity and recovery time of FA, respectively. Spectrophotometric determination of FA in fermented broth sample is not a common methodological approach. Thus, development of a simple and rapid spectrophotometric method for FA estimation in fermented broth samples can be an interesting option to investigate.
In the present investigation, a time and cost effective colorimetric procedure was developed for the quantification of FA in the fermented broth samples. Different agro-industrial wastes viz. brewery wastewater (BW) and apple pomace ultrafiltration sludge (APS), apple pomace with rice husk (AP) and pulp and paper solid waste (PPSW) were screened and optimized for the enhanced production of FA through fermentation employing R. oryzae 1526 (R. oryzae). Cost-effective immobilization technique was used for enhanced FA production. Impact of different concentrations of micro- and nanoparticles of ZnO, Fe3O4 and MnO2 on FA production was also investigated. Finally, application of calcium carbonate nanoparticles (CCNPs) and microwave irradiation (MWI) in FA production and recovery, respectively, were investigated.
For BW, with all the optimized growth conditions (pH 6, 25 °C, 200 rpm, 5% (v/v) inoculum size, 25 g/L total solids concentration, and pellet diameter of 0.465 ± 0.04 mm), the highest concentration of FA achieved was 31.3 ± 2.77 g/L.
In the immobilization study with muslin cloth (MC), production level and volumetric productivity of FA were markedly increased from 30.56 ± 1.40 g/L to 43.67 ± 0.32 g/L and 0.424 g/(L h) to 1.21 g/(L h) as compared to free-cell fermentation. In another study with hen’s egg shells (EGS), as compared to free-cell, biofilms (formed on EGS) mediated submerged fermentation markedly enhanced the production and volumetric productivity of fumaric acid from 30.23 ± 1.23 g/L to 47.22 ± 0.77 g/L and 0.419/(L h) to 1.657 g/(L h), respectively. EGS also served the purpose of source of CaCO3.
The study with PPSW resulted in good productivities of FA for submerged and solid state fermentation with different particle ranges (1.7 mm < x ≤ 3.35 mm, 850 μm < x ≤ 1.7 mm, 300 μm < x ≤ 850 μm, 75 μm < x ≤ 300 μm and 33 μm < x ≤ 75 μm). In submerged fermentation with, a maximum of 23.47 ± 0.70 g/L of FA was obtained with 33 μm < x ≤ 75 μm. Solid state fermentation with 75 μm < x ≤ 300 μm particle size resulted in highest FA production (41.45 g/kg dry weight of PPSW) after 21 days.
For submerged fermentation study with APSU, 40 g/L of total solids concentration of APUS, pH 6.0, 30 oC, 200 rpm flask shaking speed and 72 h of incubation were found to be optimum for FA production (25.2 ± 1.0 g/L, 0.350 g/(L h)). Solid state fermentation resulted in 52 ± 2.67 g FA per kg dry weight of AP under all optimized conditions.
The experiments carried out with AP in rotating drum type solid-state bench scale fermenter resulted in FA concentration of 138 ± 9.11 g per kg dry weight of AP at all optimized conditions. Total phenolic content of AP was considerably increased from 185 ± 10.5 mg/g to 345 ± 8.5 mg/g of lyophilizate.
The investigation on the impact of different concentrations (200-1000 μg/mL) of micro- and nanoparticles of ZnO, Fe3O4 and MnO2 on FA production showed Fe3O4 micro- and nanoparticles to be the most biocompatible to the fungus R.oryzae.
The application of CCNPs reduced FA neutralization timing by around 160 seconds. Moreover, CCNPs enhanced the volumetric productivity of FA from 0.47 g/(L h) to 0.74 g/(L h). Viscosities of CCNPs were found to be lower than calcium carbonate microparticles (CCMPs). Under MWI heating, 10 ± 1 min was found to be sufficient for recovery of FA and this was much lower than conventional heating timing of 28 ± 1min
ESSAYS ON LOBBYING AND CRIME
No full textWe investigate whether and when the social network among legislators aid a
lobby group in influencing voting decisions of legislators. The baseline model
involves a group of legislators that are connected via an exogenously given network.
Each legislator can vote for the status-quo policy or an alternative policy.
A lobby can credibly promise payments to legislators if they vote for the alternative.
The lobby chooses these payments to maximize the sum of legislators’
probabilities of voting for the alternative policy subject to a budget constraint.
Legislators value the payment they receive, and all legislators are assumed to
have a common preference bias towards (or against) the status quo policy. The
key feature of the model is that a legislator derives additional utility from voting
in line with those legislators with whom she is directly connected in her
network
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