An ontology based multi-agent system to support HABIO outsourcing framework

In recent years the widespread application of outsourcing to help improve finance and maintain competitiveness is growing rapidly, and has been accompanied by a growth of academic research in this field. Most of the outsourcing literature has focused primarily on the social and cultural impacts, the organisational and management perspectives of outsourcing and very few tools have been developed to assist managers in making outsourcing decisions. Incorrect decision-making in outsourcing can lead to devastating consequences for their business. To guide decision makers in managing the complexity of outsourcing a holistic approach to outsourcing has been developed by taking business, information and organisational perspectives (HABIO). The purpose of this paper is to demonstrate how HABIO can be applied to help managers evaluate the impact of their decision-making by providing them with a set of ‘what-if’ scenarios, which are enacted by intelligent agents. The case example, discussed in this paper, demonstrates that HABIO can be applied effectively using a multi-agent system to analyse the outsourcing decision for a call centre sector in the retail industry. A prototype of the multi-agent system is presented where intelligent agents are endowed with specific domain ontologies, appropriate to solve a specific problem, and with a reasoning mechanism to achieve specific goals and to collaborate together to produce a set of “what-if scenarios” to the outsourcing managers.     

Reconstruction of cellular biological structures from optical microscopy data

Developments in optical microscopy imaging have generated large high-resolution data sets that have spurred medical researchers to conduct investigations into mechanisms of disease, including cancer at cellular and subcellular levels. The work reported here demonstrates that a suitable methodology can be conceived that isolates modality-dependent effects from the larger segmentation task and that 3D reconstructions can be cognizant of shapes as evident in the available 2D planar images. In the current realization, a method based on active geodesic contours is first deployed to counter the ambiguity that exists in separating overlapping cells on the image plane. Later, another segmentation effort based on a variant of Voronoi tessellations improves the delineation of the cell boundaries using a Bayesian formulation. In the next stage, the cells are interpolated across the third dimension thereby mitigating the poor structural correlation that exists in that dimension. We deploy our methods on three separate data sets obtained from light, confocal, and phase-contrast microscopy and validate the results appropriately.     

Spinal neurilemmomas and neurofibromas: central dot sign in postgadolinium MRI

The MR studies of three histologically proven spinal neurilemmomas and neurofibromas were reviewed retrospectively. There were two benign neurilemmomas (schwannomas) and one neurofibroma. The common characteristic of these cases was a central low intensity focus ("dot") seen on postcontrast T1-weighted imaging. The low intensity foci corresponded histologically to a congeries of changes including edema, microcysts, foam cells, hyalinization of blood vessels, old hemorrhage, and dystrophic calcification.     

The role of pH in thaumasite sulfate attack

The thaumasite form of sulfate attack (TSA) has been recognised in recent years as a distinct mechanism by which degradation of buried concrete can occur in the presence of an external source of sulfate ions. There is, however, disagreement about the role of pH. It has been proposed that attack by sulfuric acid, produced by oxidation of pyrite, is sometimes the primary cause of deterioration. Others believe that the acid is rapidly neutralised giving a higher concentration of sulfate ions in the ground, hence increasing the extent of attack. The aim of the laboratory study reported here was to understand the role of sulfuric acid in TSA by examining concrete cubes, made from three types of cement and two types of aggregate, immersed at low temperature in two solutions, one alkaline corresponding to BRE Design Sulfate Class DS-3 and the other acidic. It is concluded that the presence of acid does not promote the formation of thaumasite. Although degradation of the concrete was observed in acid conditions, the mechanism was not TSA as observed in alkaline conditions.     

Chlorpropamide-induced hypoglycemia: successful treatment with diazoxide

A healthy adolescent boy was treated on two occasions for an overdose of chlorpropamide (Diabinese). Glucose therapy alone was not sufficient to control the hypoglycemia, but the administration of glucose plus diazoxide raised the blood sugar to supranormal levels. A bolus of intravenous glucagon briefly raised the blood sugar level to within normal limits, increased the blood ketones but also augmented insulin secretion. An overdose of sulfonylurea may cause prolonged and fatal hypoglycemia. Rational therapy, both in diabetic and normal persons, is glucose plus an "insulin antagonist." The administration of diazoxide was effective in our patient, substantially reducing the plasma insulin level; this agent may be the "insulin-antagonist" of choice for use in sulfonylurea-induced hypoglycemia.     

Specifying and enforcing application-level Web security policies

Application-level Web security refers to vulnerabilities inherent in the code of a Web-application itself (irrespective of the technologies in which it is implemented or the security of the Web-server/back-end database on which it is built). In the last few months, application-level vulnerabilities have been exploited with serious consequences: Hackers have tricked e-commerce sites into shipping goods for no charge, usernames and passwords have been harvested, and confidential information (such as addresses and credit-card numbers) has been leaked. We investigate new tools and techniques which address the problem of application-level Web security. We 1) describe a scalable structuring mechanism facilitating the abstraction of security policies from large Web-applications developed in heterogeneous multiplatform environments; 2) present a set of tools which assist programmers in developing secure applications which are resilient to a wide range of common attacks; and 3) report results and experience arising from our implementation of these techniques.     

Dedicated temperature sensing with c-axis oriented single-crystal ruby (Cr/sup 3+/:Al/sub 2/O/sub 3/) fibers: temperature and strain dependences of R-line fluorescence

Single-crystal fibers of ruby (Cr/sup 3+/:Al/sub 2/O/sub 3/) with approximately 0.1 wt.% Cr/sup 3+/ have been produced by the laser heated pedestal growth (LHPG) technique. The fluorescence emissions of the R/sub 1/ and R/sub 2/ lines were studied as functions of temperature and strain. Fluorescence decay lifetime measurements indicate that these fibers may be suitable for thermometric applications up to 973 K while strain measurements show only a very weak dependence. Similarly, characterization of the R-line shifts also show a weak strain sensitivity and an appreciably larger change with temperature. One fiber sample has been tested to destruction to demonstrate this weak strain dependence. Single-crystal ruby fibers are, thus, found to be potential candidates for dedicated temperature sensing from room temperature to /spl sim/923 K.     

Durability of CFRP cables exposed to simulated concrete environments

One of the main causes of structural deficiency in concrete bridges is the deterioration of the constituent materials. Some transportation agencies have started exploring the use of carbon fiber reinforced polymers (CFRP) as a corrosion-resistant alternative to steel prestressing materials for longer lasting concrete bridge structures. To implement CFRP in prestressed concrete bridge structures with more confidence, an understanding of the challenges pertaining to durability under in-service environmental conditions is essential. This paper explores the effects of temperature with alkaline and alkaline/chloride solutions on material properties over time, in the context of reinforced and prestressed concrete structures for transportation applications. The durability testing yielded several key findings: (1) higher temperatures accelerate degradation, (2) moisture sorption was the primary process responsible for the observed degradation, with plasticization and microcracking as the controlling mechanisms leading to fiber–matrix interfacial debonding, and (3) a relaxation-based analytical model was implemented to predict residual properties after environmental exposure, showing promising agreement with experimental data.     

‘Day Labour’ and ‘Xenophobia’ in South Africa: the Need for Mixed Methods Approaches in Policy-Orientated Research

Much policy-orientated research in South Africa relies solely on large-scale surveys. Little or no case study research is undertaken as part of studies despite broad international acknowledgement of the benefits of mixing methods. In the South African poverty and demographic literature, strong arguments have been made for the incorporation of case study approaches to arrive at a deeper and more accurate understanding of social phenomena. This paper, which draws on an ethnographic study of ‘day labourers’ (both South African and foreign) in Cape Town, together with an extensive range of relevant literature, extends this line of argument to research on casual employment and relations between South Africans and foreign nationals. It highlights a number of questionable assumptions and superficial analyses present in previous survey-based research on these topics. It also discusses the potential contribution of more case study work and some of the practical issues associated with linking methodologies in development research.