INVESTIGATION OF THE STABILITY OF LIQUID AND AIR FILMS BY SYNCHRONIZED TRI-WAVELENGTH REFLECTION INTERFEROMETRY MICROSCOPE

Liquid films are widely involved in many processes, such as froth flotation, oil extraction, foam/bubble stabilization, etc. In the meantime, air films are commonly seen in diverse fields like dust control, ink print, coating industry, and so on. Stabilities of these liquid/air films are of great importance to improve the processes. As more and more researchers are paying increasing attention to liquid/air films, tremendous efforts have been made to explore the properties of the films. On the one hand, some theoretical models have also been well developed in recent decades. State-of-the-art technologies, such as AFM, SFA, and RICM, have also been employed to visualize the films in either a direct or indirect manner. However, due to the limitations of the techniques, it is still challenging to fully uncover the mechanisms of the film stabilities. A new and powerful methodology to characterize the film properties has been a top priority. In this work, a novel technique, namely Synchronized Tri-wavelength Reflection Interferometry Microscope (STRIM), was developed in our lab. It allows the accurate measurement of a separation distance within a range of few nanometers to micrometers. Based on the previous RICM, STRIM employs two additional light sources and achieves the determination of the absolute distance. The accuracy of the film thickness measurements was found to be within 1 nm over a range of 0-200 nm and within 3 nm over the range of 200–1000 nm. By recording the thinning process of films, STRIM is able to reconstruct the spatiotemporal profiles, which contain massive information. First, the conditions under which the films are stable or unstable are the urges to figure out for industrial applications. Besides, the films\u27 stabilities are closely related to the interfacial properties, and thus they can be alternative indicators of some essential properties, such as hydrophobicity. Additionally, the interactions and surface forces across the films between involved surfaces can be calculated by the dynamic film thinning kinetics, unraveling the underlying mechanisms for the processes of interest. Furthermore, other approaches, including AFM, contact angle measurement, and flotation, are also referred to in this work and confirm the drawn conclusions. The STRIM can investigate both the liquid and air films with the flexibility of controlling the involved objects like the surfaces with adjustable hydrophobicity and media with designed properties. This newly-developed equipment has the potential to be extensively used within the colloid and interfacial science and engineering areas

The characteristics of the CAT to CAD to rapid prototyping system

ThesisComputer Aided Design (CAD), Rapid Prototyping (RP) and Computer Aided Tomography (CAT) technologies were researched. The project entails a unique combination of the abovementioned technologies, which had to be mastered by the author, on local and international terms. Nine software packages were evaluated to determine the modus operandi, required input and final output results. Fifty Rapid Prototyping systems were investigated to determine the strong and weak areas of the various systems, which showed that prototype materials, machine cost and growing time play an essential role. Thirty Reverse Engineering systems were also researched. Six different RE methods were recorded with several commercial systems available. Nineteen case studies were completed by using several different Computer Aided Tomography (CAT) and Magnetic Resonance Imaging (MRI) centers. Each scanning centre has different apparatus and is discussed in detail in the various case studies. The focus of this project is the data transfer of two dimensional CAT scanning data to threedimensional prototypes by using Reverse Engineering (RE) and Rapid Prototyping (RP). It is therefore of cardinal importance that one is familiar and understands the various fields of interest namely Reverse Engineering, Computer Aided Tomography and Rapid Prototyping. Each of these fields will be discussed in detail, with the latest developments in these fields covered as well. Case studies and research performed in the medical field should gain the medical industry's confidence. Constant marketing and publications will ensure that the technology is applied and transferred to the industry. Commercialisation of the technology is of utmost importanc

Developing Maintenance Cultures in UN Police Peacekeeping Operations

This report provides an analysis and evaluation of maintenance cultures in United Nations Police Contributing Countries (PCC) receiving funding for Formed Police Units from the United States. The US Department of State, Bureau of International Narcotics and Law Enforcement Affairs (INL) recognized a marked lack of research on maintenance cultures in police agencies receiving foreign funding and sought to build a base of knowledge to aid in creating and sustaining maintenance cultures within these organizations. The INL also requested analysis and evaluation of maintenance cultures in five specific African PCCs (Cameroon, Ghana, Rwanda, Senegal, and Togo), as well as recommendations to create and sustain maintenance cultures specific to these countries. By establishing effective maintenance cultures, INL seeks to ensure that equipment purchased with funding from the United States will operate effectively throughout the manufacturer's estimated life-span

Morphological convergence as on-line lexical analogy

The English past-tense contains pockets of variation, where regular and irregular forms compete (e.g. learned/learnt, or weaved/wove). Individuals vary considerably in the degree to which they prefer irregular forms. This paper examines the degree to which individuals may converge on their regularization patterns and preferences. We report on a novel experimental methodology, using a cooperative game involving nonce verbs. Analysis of participants' post-game responses indicates that their behavior has shifted in response to an automated co-player's preferences, on two dimensions. First, players regularize more after playing with peers with high regularization rates, and less after playing with peers with low regularization rates. Second, players' overall pattern of regularization is also affected by the particular distribution of (ir)regular forms produced by the peer. We model the effects of the exposure on participants' morphological preferences, using both a rule-based model and an instance-based analogical model (Albright & Hayes, 2003; Nosofsky, 1988). Both models contribute separately and significantlyto explaining participants' pre-exposure regularization processes. However, only the instance-based model captures the shift in preferences that arises after exposure to the peer. We argue that the results suggest an account of morphological convergence in which new word forms are stored in memory, and online generalizations are formed over these instances

Embedding requirements within the model driven architecture.

The Model Driven Architecture (MDA) is offered as one way forward in software systems modelling to connect software design with the business domain. The general focus of the MDA is the development of software systems by performing transformations between software design models, and the automatic generation of application code from those models. Software systems are provided by developers, whose experience and models are not always in line with those of other stakeholders, which presents a challenge for the community. From reviewing the available literature, it is found that whilst many models and notations are available, those that are significantly supported by the MDA may not be best for use by non technical stakeholders. In addition, the MDA does not explicitly consider requirements and specification. This research begins by investigating the adequacy of the MDA requirements phase and examining the feasibility of incorporating a requirements definition, specifically focusing upon model transformations. MDA artefacts were found to serve better the software community and requirements were not appropriately integrated within the MDA, with significant extension upstream being required in order to sufficiently accommodate the business user in terms of a requirements definition. Therefore, an extension to the MDA framework is offered that directly addresses Requirements Engineering (RE), including the distinction of analysis from design, highlighting the importance of specification. This extension is suggested to further the utility of the MDA by making it accessible to a wider audience upstream, enabling specification to be a direct output from business user involvement in the requirements phase of the MDA. To demonstrate applicability, this research illustrates the framework extension with the provision of a method and discusses the use of the approach in both academic and commercial settings. The results suggest that such an extension is academically viable in facilitating the move from analysis into the design of software systems, accessible for business use and beneficial in industry by allowing for the involvement of the client in producing models sufficient enough for use in the development of software systems using MDA tools and techniques

Structural studies on some capsular antigens from escherichia coli and klebsiella

A review of the structural studies of bacterial capsular polysaccharides (K-antigens) from Escherichia coli and Klebsiella, and of the trends in modern chemical and instrumental techniques available for the analysis of carbohydrate material is presented. The structural elucidations of the capsular polysaccharides from E. coli K37 and K55, and Klebsiella K39 are reported with comments on the novelty and possible immunological significance of the structures. The usefulness of the bacteriophage degradation technique has been emphasized using the polysaccharides from E. coli K55, and Klebsiella K30 and K39 to demonstrate the scope of the reactio