2,041 research outputs found
Detergency in Liquid CO2
No full textIn this dissertation we study Detergency in liquid Carbon Dioxide. Detergency is the cleaning performance of additives, surfactants in particular, in washing fluids. Liquid CO2 is under consideration, for environmental and toxicological reasons, to replace perchloro-ethylene as the solvent in textile dry cleaning technology. Inherent problems of such a transition were confronted with the methodology of chemical engineering design. The Basic Cycle of Design (BCD) approach was used as a pathway for designing a detergent. The BCD also establishes the structural framework of the thesis, which can, therefore, be read as records from a successful product engineering project, in which an effective detergent has been designed for a new dry cleaning solvent. The Dynamic Detergency Model (DDM), which succeeds to explain the role of surfactants in the washing operation, is used as a rational starting point for the design of a detergent in liquid CO2. According to this model, such a surfactant must be: sparingly soluble in the solvent, surface-active and able to form micelles in the solution. The different experiments carried out (solubility, interfacial-tension and dye solubilisation measurements), show that a number of molecules of the homologous polyoxyethylene/alkane series, generally described by the shorthand formula CiEj did indeed behave as surfactants and can be then considered detergents for liquid CO2. In the technical evaluation of the detergents, at laboratory as well as at semi-pilot scale, high washing performances were obtained. They are, indeed, as good for dry cleaning textiles as the present perchloro-ethylene (Perc) technology.Applied Science
'Her Irish Heritage' : Annie M.P Smithson and autobiography
No full textThis paper examines some aspects of the work of Annie M.P. Smithson, the author of 21 romance novels between 1917 and 1946. Her attitudes towards women, religion and politics are explored, and the importance of autobiography in her fiction discussed.Cet article analyse divers aspects de l'oeuvre d'Annie M.P. Smithson, l'auteur de vingt et un romans 'romanesques' publiés entre 1917 et 1946. Il étudie son attitude concernant les femmes, la religion, la politique, ainsi que le rôle de l'autobiographie dans sa fiction.Walsh Oonagh. 'Her Irish Heritage' : Annie M.P Smithson and autobiography. In: Études irlandaises, n°23-1, 1998. pp. 27-42
Il ruolo della linguistica in un'iniziativa di internazionalizzazione
No full textThe author deals with the role of linguistic sciences and language teaching in the internationalization project of an e-learning Specialization Course
A classification of crosscutting concerns and the implications for aspect-oriented refactoring
No full textRefactoring software to apply aspect oriented solutions requires a clear understanding of what are the potential crosscutting concerns and which aspect solutions to replace them with. This process can benefit from the recognition of recurring generic concerns and their reusable aspect solutions.
In this paper, we propose a classification of crosscutting concerns in sorts based on the analysis of various refactoring efforts. We discuss how sorts help concern understanding and refactoring, how they support the identification of crosscutting concerns, and how they can contribute to the evolution of aspect languages
Understanding Wikipedia as a Resource for Opportunistic Learning of Computing Concepts
No full textPosts on on-line forums where programmers look for information often include links to Wikipedia when it can be assumed the reader will not be familiar with the linked terms. A Wikipedia article will thus often be the first exposure to a new computing concept for a novice programmer. We conducted an exploratory study with 18 novice programmers by asking them to read a Wikipedia article on a common computing concept that was new to them, while using the think-aloud protocol.We performed a qualitative analysis of the session transcripts to better understand the experience of the novice programmer learning a new computing concept using Wikipedia. We elicited five themes that capture this experience: Concept Confusion, Need for Examples, New Terminology, Trivia Clutter, and Unfamiliar Notation. We conclude that Wikipedia is not well suited as a resource for the opportunistic learning of new computing concepts, and we recommend adapting information sharing practices in on-line programmer communities to better account for the learning needs of the users.Martin P. Robillard, Christoph Treud
The influence of steady blowing and roughness on transitional separated boundary layers
No full textThis paper presents the results of a study between two types of forcing, namely steady blowing and a tripwire, on the control of laminar separated boundary layers. The analysis focuses on the differences in the transition process between these two types of forcing. This effect will be studied using direct numerical simulation. The main differences consists in the coherent structures formed during transition and the overall kinetic energy growth
Gusmani grecista
No full textThe author deals with the Roberto Gusmani's works about Ancient Greek language
Skin-Friction Measurements on Mathematically Generated Roughness in a Turbulent Channel Flow
No full textEngineering systems are affected by surface roughness, however, predicting frictional drag has proven to be challenging. The present work takes a systematic approach by generating and manufacturing surfaces roughness where surface statistics, such as rms, skewness and power-spectral density can be controlled. The frictional drag on these surfaces is measured in a turbulent channel flow facility
Recommending Refactoring Operations in Large Software Systems
No full textDuring its lifecycle, the internal structure of a software system undergoes continuous modifications. These changes push away the source code from its original design, often reducing its quality. In such cases, refactoring techniques can be applied to improve the readability and reducing the complexity of source code, to improve the architecture and provide for better software extensibility. Despite its advantages, performing refactoring in large and nontrivial software systems might be very challenging. Thus, a lot of effort has been devoted to the definition of automatic or semi-automatic approaches to support developer during software refactoring. Many of the proposed techniques are for recommending refactoring operations. In this chapter, we present guidelines on how to build such recommendation systems and how to evaluate them. We also highlight some of the challenges that exist in the field, pointing toward future research directions
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