Dynamics of freely moving plates connected by a shallow liquid bridge

We study the dynamics of freely moving plates connected by a shallow liquid bridge via analytic and experimental methods. The gap between the plates is used as a small parameter within a lubrication approximation, reducing the problem to an Abel equation of the second kind. Analysis of the governing differential equation yields two novel physical phenomena: (1) An impulse-like peak in the force applied by the liquid bridge on the plates, obtained from a uniform asymptotic solution for small capillary numbers. (2) Both linear and non-linear oscillations of the system for the case of surfaces with low wettability, obtained from small perturbations of the system around the equilibrium point. An experimental setup examining the motion of freely moving plates was constructed, yielding experimental data which compared favorably with the analytic results and specifically displayed the predicted oscillations and impulse-like peak of the applied force. The application of the current analysis to the manipulation of solid bodies and possible future research directions are discussed

Experimental Investigation on Pervious concrete with Metakaolin

Pervious concrete is a type of light weight porous concrete with no fine or with small percentage of fine aggregate. It is generally used for flatwork applications, which allows water from precipitation and other sources to pass directly through, thereby reducing the runoff from a site and allowing ground water recharge. This study aims to experimentally investigate the mechanical and hydraulic properties of pervious concrete with different replacement levels of metakaolin. Pervious concrete for pavement applications having a porosity of 20-25% with cement-aggregate ratio of 1:4 and w/c ratio of 0.36 is established based on permeability, porosity and strength parameters.  Metakaolin were incorporated in pervious concrete by replacing cement at 5%, 10% and 15% by weight of cement which helps in increasing the mechanical properties of pervious concrete. The strength parameters increased about 12.24%, 23.95%, 13.97% for compressive strength, split tensile strength and flexural strength respectively for 10% metakaolin replacement and hydraulic properties decreased as the percentage of metakaolin increased

Simulation of multi-deck medium temperature display cabinets with the integration of CFD and cooling coil models

This is the post-print version of the final paper published in Applied Energy. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2010 Elsevier B.V.In this paper, the model for the multi-deck medium temperature display cabinets is developed with the integration of CFD and cooling coil sub-models. The distributed method is used to develop the cooling coil model with the airside inputs from the outputs of the CFD model. Inversely, the airside outputs from the cooling coil model are used to update the boundary conditions of the CFD model. To validate this cabinet model, a multi-deck medium temperature display cabinet refrigerated with a secondary refrigerant cooling coil was selected as a prototype and mounted in an air conditioned chamber. Extensive tests were conducted at constant space air temperature and varied relative humilities. The cabinet model has been validated by comparing with the test results for the parameters of air at different locations of the flow path, and temperatures of refrigerant and food product, etc. The validated model is therefore used to explore and analyse the cabinet performance and control strategies at various operating and design conditions.DEFR

Migraciones encadenadas y mareas neoliberales: Etnografía crítica de la migración kichwa a través del Atlántico

El impacto de las políticas neoliberales en la movilidad humana ha sido planetario. Y profundamente desestabilizador. Aquí quiero centrarme en las migraciones a través del espacio Atlántico, y en el modo en que el neoliberalismo ha afectado nuestras concepciones de identidad colectiva y nuestros horizontes de soberanía. Lo haremos a través de la mirada etnográfica, con un trabajo de investigación de largo recorrido que iniciamos en el año 2000 y que nos llevó a acompañar los procesos de migrantes indígenas ecuatorianos en España así como, después del impacto de la crisis, a través de las dolorosas decisiones sobre el retorno o la permanencia en Europa. A través de esta etnografía podemos entender mejor a) cómo la movilidad humana en tiempos neoliberales es intermitente y flexible, configurando lo que denominamos “migraciones encadenadas”; b) cómo el régimen de incorporación neoliberal abre y cierra esclusas generando ciudadanías flexibles a la par que superfluas; c) cómo la creatividad y agencia humanas se muestran rebeldes, no obstante estos impactos, creando nuevas cartografías alternativas de vecindad a través de sus prácticas, y, finalmente, d) el modo en que estructuras poscoloniales y desigualdades se reproducen en el espacio global a través de un cierto multiculturalismo simbólico compatible con el racismo y la violencia cotidiana de la vulneración de derechos humanos fundamentales.The impact of neoliberal policies on human mobility has been planetary. And profoundly destabilizing. Here I want to focus on migration across the Atlantic space, and how neoliberalism has affected our conceptions of collective identity and our sovereignty horizons. We will do it through the ethnographic gaze, with a long term research that began in 2000 and that led us to accompany the processes of indigenous Ecuadorian migrants in Spain and, after the impact of the crisis, through painful decisions about the return or permanence in Europe. Through this ethnography we can understand better a) how human mobility in neoliberal times is intermittent and flexible, forming what we call “chained migrations”, b) how the neoliberal incorporation regime opens and closes locks generating flexible and at the same time superfluous citizenships, c) how creativity and human agency are shown rebels, however these impacts, creating new alternatives maps of neighborhood through their practices, and finally d) how postcolonial structures and inequalities are reproduced in the global space through a certain symbolic multiculturalism compatible with racism and daily violence of the violation of fundamental human right

English medium undergraduate classes: are they useful for students’ language development?

Like other developing countries, Sri Lanka too introduced English Medium Instruction (EMI) at tertiary level undergraduate courses with a view of enhancing the English proficiency of the students. The assumption behind this introduction was that when the students were given opportunities for being exposed to plenty of input in a second language (SL) their language proficiency would develop. Generally, in Sri Lankan universities, English is taught as a second language. However, in reality, the EMI students do not show any remarkable achievements in their language proficiency, as expected. However, many of the EMI students whose language proficiency was weaker at the entry point to the university seem to continue to struggle, after three to four years of being in the English medium classes, to cope with the problems associated with the medium of instruction. This study aimed to find out whether there was any improvement in the language proficiency of the science undergraduates of a Sri Lankan university by following their courses in EMI. Also, it aimed at identifying the challenges faced by them in EMI classes. This study was conducted with a group of undergraduates who were already identified as weaker in their proficiency in English. The study revealed that the students had several issues concerning their English language proficiency including issues arising from lack of foundation knowledge in English from schools which in turn hampered their learning of the content subjects. Students claimed that they developed only the listening skill as a result of EMI and that there was no significant improvement of the other skills, namely speaking, reading or writing. The findings of this study were used to provide additional language support for the students

Políticas de Representación: construcción y marketing de nuevas identidades en el espacio político-mediático

This article explores some premilinary findings of the research on “Politics of Representation in the Transnational Migratory Field: Production, Distribution and Consumption of Media in Migratory Context” (CSO2008-03022). From an initial theoretical reflection on the main challenges Anthropology finds in the globalization context, we describe and analyze the recent burst of mass media oriented towards immigrant population in Spain. I delve into the analysis of content of these media, based on a quantitative and qualitative research, comparing briefly the results with dominant media. I analyze the construction of the “news” in migratory, transnational and cultural dimensions, exploring the emergence of a new ethnocultural category new in Spain, that of “Latin@s”. I finally offer three Ideal Types of the articulation of Latin American journalist with their audiences and their sociological grass roots organizations and communities: instrumental, clientelist, and organic. I then conclude through a series of considerations about the importance of the ethnographic work on the public space through a transnational perspective that deals with political communication processes in the new mediaspaces which shape our social world as citizens.Este trabajo presenta algunos hallazgos preliminares de la investigación sobre “Politicas de representación en el campo migratorio transnacional: producción, distribución y consumo de contenidos mediáticos en el contexto migratorio” (CSO2008-03022). A partir de la consideración teórica de algunos retos centrales planteados a la antropología en el contexto de globalización, describimos y analizamos la aparición reciente pero masiva de medios de comunicación orientados hacia la población inmigrante en España. Se profundiza en el análisis del contenido ofertado por estos medios, a partir de un estudio cuantitativo y cualitativo de los mismos, trazando una comparación con el espacio mediático generalista. Se analiza la construcción de la noticia en sus vertientes migratorias, transnacionales y de manera específica en su dimensión cultural, explorando la aparición de la nueva categoría etnocultural de “latin@s” en nuestro entorno. Finalmente, se ofrecen tres tipos ideales, referentes al tipo de vínculo que los nuevos periodistas de origen latinoamericano establecen con su “audiencia” y/o base social: instrumental, clientelar y orgánico. Concluimos con una serie de consideraciones sobre la importancia del estudio etnográfico del espacio público a través de una perspectiva transnacional, que aborde los procesos de comunicación política en los espacios político-mediáticos que nos configuran como ciudadanos

Introduction Ethnographies and Emergencies in the Mediterranean: Black Holes of Our Modernity

Esta sección es una respuesta desde la antropología al trágico despropósito de la cobertura mediática y la muerte de miles de seres humanos en el mar que une el sur de Europa con el norte de África, el Mediterráneo. A la economía moral del asilo y a las retóricas del humanitarismo basadas en «crisis» y «urgencias» en vez de justicia social y derechos humanos. Miramos al Mediterráneo desde la etnografía, con una forma particular de analizar y vivir las fronteras: lejos de flashes mediáticos y populismos políticos, cerca de las historias e interpretaciones de las gentes que las transitan. Abordamos las fronteras desde su realidad actual en el Mediterráneo: interconectadas, deslocalizadas, mucho más amplias de lo que la ley define como frontera europea. Una «olla a presión», agravada por el efecto del control policial en países de tránsito, como Marruecos, Libia, o Turquía. Un régimen fronterizo que alcanza el territorio europeo, con los Centros de Internamiento y el control sobre extranjeros asentados en nuestros países europeos. Una realidad fronteriza abrumadora que pone en cuestión la vigencia de los principios éticos y políticos que animó la construcción de Unión EuropeaThis section is an anthropological response to the atrocity of the media coverage and death of thousands of human beings in the sea linking Southern Europe with Northern Africa, the Mediterranean. It responds to the moral economy of asylum and the rhetoric of humanitarianism based on «crisis» and «emergencies» rather than social justice and human rights. We consider the Mediterranean from the ethnographic perspective, analysing and experiencing borders in a specific way, away from media cameras and political populism, and closely in touch with the stories and interpretations of the people who cross them. We address Mediterranean borders as they really are at the current moment: interconnected, delocalized, much more extensive than defined by law as «the European frontier». They constitute a «pressure cooker», exacerbated by the effects of police controls in transit countries like Morocco, Libya and Turkey. This border Regime extends to the European territory contains through the 400 immigration detention centres and the monitors of foreigners settling in Europe. The overwhelming borderland regime calling into question the validity of the ethical and political principles that led to the construction of the European Unio

A New Computational Framework for Efficient Parallelization and Optimization of Large Scale Graph Matching

There are so many applications in data fusion, comparison, and recognition that require a robust and efficient algorithm to match features of multiple images. To improve accuracy and get a more stable result is important to take into consideration both local appearance and the pairwise relationship of features. Graphs are a powerful and flexible data structure, allowing for the description of complex relationships between data elements, whose nodes correspond to salient features and edges correspond to relational aspects between features. Therefore, the problem of graph matching is to find a mapping between the two sets of nodes that preserves the relationships between them as much as possible. This graph-matching problem is mathematically formulated as an IQP problem which solving it is NP-hard, and obtaining exact Optima only plausible for very small data. Therefore, handling large-scale scientific visual data is quite limited, necessitating both efficient serial algorithms, as well as scalable parallel formulations. In this thesis, we first focused on exploring techniques to reduce the computation cost as well as memory usage of Pairwise graph matching by adopting a heuristic pruning strategy together with a redundancy pattern suppression scheme. We also modified the structure of the affinity matrix for minimizing memory requirement and parallelizing our algorithm by employing CPU’s and GPU’s accelerated libraries. Any pair of features with similar distance from first image results in same sub-matrices, therefore instead of constructing the whole affinity matrix, we only built the sub-blocked affinity for those distinct feature distances. By employing this scheme not only saved large memory and reduced computation time tremendously but also, the matrix-vector multiplication of gradient computation performed in parallel, where each block-vector calculation computed independently without synchronization. The accelerated libraries such as MKL, cuSparse, cuBlas and thrust applied to solving the GM problem, following the scheme of the spectral matching algorithm. We also extended our work for Multi-graph imaging, since many tasks require finding correspondences across multiple images. Also, considering more graph improves the matching accuracy. Most algorithms obtain approximate solutions for solving the GM NP-hard problem, result in a weak optimal solution. Therefore, we proposed a new solver, which iteratively modified the affinity matrix and binarized the solution by optimizing the original problem with its integer constraints

Mobile Big Data Analytics in Healthcare

Mobile and ubiquitous devices are everywhere around us generating considerable amount of data. The concept of mobile computing and analytics is expanding due to the fact that we are using mobile devices day in and out without even realizing it. These mobile devices use Wi-Fi, Bluetooth or mobile data to be intermittently connected to the world, generating, sending and receiving data on the move. Latest mobile applications incorporating graphics, video and audio are main causes of loading the mobile devices by consuming battery, memory and processing power. Mobile Big data analytics includes for instance, big health data, big location data, big social media data, and big heterogeneous data. Healthcare is undoubtedly one of the most data-intensive industries nowadays and the challenge is not only in acquiring, storing, processing and accessing data, but also in engendering useful insights out of it. These insights generated from health data may reduce health monitoring cost, enrich disease diagnosis, therapy, and care and even lead to human lives saving. The challenge in mobile data and Big data analytics is how to meet the growing performance demands of these activities while minimizing mobile resource consumption. This thesis proposes a scalable architecture for mobile big data analytics implementing three new algorithms (i.e. Mobile resources optimization, Mobile analytics customization and Mobile offloading), for the effective usage of resources in performing mobile data analytics. Mobile resources optimization algorithm monitors the resources and switches off unused network connections and application services whenever resources are limited. However, analytics customization algorithm attempts to save energy by customizing the analytics process while implementing some data-aware techniques. Finally, mobile offloading algorithm decides on the fly whether to process data locally or delegate it to a Cloud back-end server. The ultimate goal of this research is to provide healthcare decision makers with the advancements in mobile Big data analytics and support them in handling large and heterogeneous health datasets effectively on the move

Computational Modeling of Multi-Phase/Multi-Species Flows with Applications to Liquid Rocket Engines

Accurate prediction of all physical phenomena in a combustion chamber is essential for better understanding of the system performance. Atomization, evaporation, combustion, chemical kinetics, and turbulence are those processes of great importance that need to be well understood. Processes involving the liquid phase in a combustion chamber will be further complicated under supercritical conditions. More advanced and accurate numerical techniques are required to extend our understanding of the above phenomena. A computer program for multi-species/multi-phase flow was developed for NASA/MSFC in 1992. This code, called Liquid Thrust Chamber Performance (LTCP) program takes an Eulerian- Eulerian approach and is based on the Total Variation Diminishing (TVD) technique with Lax-Friedrichs upwind method. Under the NASA/ASEE SFFP the LTCP code was used to predict the performance characteristics of several engines that were of particular interest to NASA. This code was also successful in a combustion detonation study. Converting the program to the PC platform was accomplished which extends usability and makes it available to a wider range of users. The Eulerian formulation of the liquid phase provides a suitable model that can be extended to include combustion modeling under supercritical conditions. The results have been compared against the ones of other codes and available measured data. The algorithm proved to be robust and efficient for problems with stiff source terms