Modular Construction of Complete Coalgebraic Logics

We present a modular approach to defining logics for a wide variety of state-based systems. The systems are modelled by coalgebras, and we use modal logics to specify their observable properties. We show that the syntax, semantics and proof systems associated to such logics can all be derived in a modular fashion. Moreover, we show that the logics thus obtained inherit soundness, completeness and expressiveness properties from their building blocks. We apply these techniques to derive sound, complete and expressive logics for a wide variety of probabilistic systems, for which no complete axiomatisation has been obtained so far

Does "thin client" mean "energy efficient"?

The thick client –a personal computer with integral disk storage and local processing capability, which also has access to data and other resources via a network connection – is accepted as the model for providing computing resource in most office environments. The Further and Higher Education sector is no exception to that, and therefore most academic and administrative offices are equipped with desktop computers of this form to support users in their day to day tasks. This system structure has a number of advantages: there is a reduced reliance on network resources; users access a system appropriate to their needs, and may customise “their” system to meet their own personal requirements and working patterns. However it also has disadvantages: some are outside the scope of this project, but of most relevance to the green IT agenda is the fact that relatively complex and expensive (in first cost and in running cost) desktop systems and servers are underutilised – especially in respect of processing power. While some savings are achieved through use of “sleep” modes and similar power reducing mechanisms, in most configurations only a small portion of the overall total available processor resource is utilised. This realisation has led to the promotion of an alternative paradigm, the thin client. In a thin client system, the desktop is shorn of most of its local processing and data storage capability, and essentially acts as a terminal to the server, which now takes on responsibility for data storage and processing. The energy benefit is derived through resource sharing: the processor of the server does the work, and because that processor is shared by all users, a number of users are supported by a single system. Therefore – according to proponents of thin client – the total energy required to support a user group is reduced, since a shared physical resource is used more efficiently. These claims are widely reported: indeed there are a number of estimation tools which show these savings can be achieved; however there appears to be little or no actual measured data to confirm this. The community does not appear to have access to measured data comparing thin and thick client systems in operation in the same situation, allowing direct comparisons to be drawn. This is the main goal of this project. One specific question relates to the overall power use, while it would seem to be obvious that the thin client would require less electricity, what of the server? Two other variations are also considered: it is not uncommon for thin client deployments to continue to use their existing PCs as thin client workstations, with or without modification. Also, attempts by PC makers to reduce the power requirements of their products have given rise to a further variation: the incorporation of low power features in otherwise standard PC technology, working as thick clients. This project was devised to conduct actual measurements in use in a typical university environment. We identified a test area: a mixed administrative and academic office location which supported a range of users, and we made a direct replacement of the current thick client systems with thin client equivalents; in addition, we exchanged a number of PCs operating in thin and thick client mode with devices specifically branded as “low power” PCs and measured their power requirements in both thin and thick modes. We measured the energy consumption at each desktop for the duration of our experiments, and also measured the energy draw of the server designated to supporting the thin client setup, giving us the opportunity to determine the power per user of each technology. Our results show a significant difference in power use between the various candidate technologies, and that a configuration of low power PC in thick client mode returned the lowest power use during our study. We were also aware of other factors surrounding a change such as this: we have addressed the technical issues of implementation and management, and the non-technical or human factors of acceptance and use: all are reported within this document. Finally, our project is necessarily limited to a set of experiments carried out in a particular situation, therefore we use estimation methods to draw wider conclusions and make general observations which should allow others to select appropriate thick or thin client solutions in their situation

A schema for cryptographic keys generation using hybrid biometrics

Biometric identifiers refer to unique physical properties or behavioural attributes of individuals. Some of the well known biometric identifiers are voice, finger prints, retina or iris, facial structure etc. In our daily interaction with others directly or indirectly, we implicitly use biometrics to know, distinguish and trust people. Biometric identifiers represent the concept of "who a person is" by gathering vital characteristics that don't correspond to any other person. The human brain to some extent is able to ascertain disparities or variation in certain physical attributes and yet verify the authenticity of a person. But this is difficult to be implemented in electronic systems due to the intense requirements of artificial decision making and hard-coded logic. This paper examines the possibility of using a combination of biometric attributes to overcome common problems in having a single biometric scheme for authentication. It also investigates possible schemes and features to deal with variations in Biometric attributes. The material presented is related to ongoing research by the Computer Communications Research Group at Leeds Metropolitan University. We use this paper as a starting step and as a plan for advanced research. It offers ideas and proposition for implementing hybrid biometrics in conjunction with cryptography. This is work in progress and is in a very preliminary stage

The analysis of user behaviour of a network management training tool using a neural network

A novel method for the analysis and interpretation of data that describes the interaction between trainee network managers and a network management training tool is presented. A simulation based approach is currently being used to train network managers, through the use of a simulated network. The motivation is to provide a tool for exposing trainees to a life like situation without disrupting a live network. The data logged by this system describes the detailed interaction between trainee network manager and simulated network. The work presented here provides an analysis of this interaction data that enables an assessment of the capabilities of the trainee network manager as well as an understanding of how the network management tasks are being approached. A neural network architecture is implemented in order to perform an exploratory data analysis of the interaction data. The neural network employs a novel form of continuous self-organisation to discover key features in the data and thus provide new insights into the learning and teaching strategies employed

Challenges in saving babies - avoidable factors, missed opportunities and substandard care in perinatal deaths in South Africa

Objective. To identify the most common avoidable factors, missed opportunities and substandard care in perinatal care in South Africa.Setting. Seventy-three state hospitals throughout South Africa representing metropolitan areas, cities and towns, and rural areas.Method. Users of the Perinatal Problem Identification Programme (PPIP) amalgamated their data to provide descriptive information on the causes of perinatal death and the avoidable factors, missed opportunities and substandard care in South Africa.Result. A total of 8 085 perinatal deaths among babies weighing 1 000 g or more were reported from 232 718 births at the PPIP sentinel sites. Avoidable factors, missed opportunities and substandard care were reported to be patient-related (between 31.5% and 47.5% of deaths), due to administrative problems (between 10.1% and 31.1% of deaths), and due to healthworker-related problems (between 28.4% and 36.0% of deaths) in the metropolitan and rural areas respectively. Figures for cities and towns lay between these ranges. Deaths due to intrapartum asphyxia and birth trauma were thought to be clearly preventable within the health system in 63.1 %, 34.4% and 35.7% of cases in the metropolitan areas, cities and towns, and rural areas respectively. Deaths due to hypertension and antepartum haemorrhage were thought to be clearly preventable within the health system in 18.7%, 15.4% and 20.0% of cases in the metropolitan areas, cities and towns, and rural areas respectively. Far fewer preventable deaths were recorded in the spontaneous preterm labour category.Conclusion. Concentration on the remediable priority problems identified (namely labour management, resuscitation of the asphyxiated neonate, and care of the premature neonate) makes the reduction of perinatalmortality in South Africa feasible and inexpensive

Why babies die - a perinatal care survey of South Africa, 2000 - 2002

Objective. To identify the major causes of perinatal mortality in South Africa.Setting. Seventy-three state hospitals throughout South Africa representing metropolitan areas, cities and towns and rural areas.Method. Users of the Perinatal Problem Identification Programme (PPIP) amalgamated their data to provide descriptive information on the causes of perinatal death and the avoidable factors, missed opportunities and substandard care in South Africa.Results. A total of 8 085 perinatal deaths among babies weighing 1 000 g or more were reported from 232 718 births at the PPIP user sites. The perinatal mortality rates for the metropolitan, city and town, and rural groupings were 36.2, 38.6 and 26.7/1 000 births, respectively. The neonatal death rate was highest in the city and town group (14.5/1 000 live births) followed by the rural and metropolitan groups (11.3 and 10.0/1 000 live births respectively). The low birth weight rate was highest in the metropolitan group (19.6%), followed by the city and town group (16.5%) and the rural group (13.0%). The most common primary cause of perinatal death in the rural group was intrapartum asphyxia and birth trauma (rate 6.92/1 000 births) followed by spontaneous preterm delivery (5.37/1 000 births). The most common primary cause of death in the city and town group was spontaneous preterm delivery (6.79/1 000 births) followed by intrapartum asphyxia and birth trauma (6.21/1 000 births) and antepartum haemorrhage (5.7/1 000 births). The metropolitan group's most common primary causes were antepartum haemorrhage (7.14/1 000 births), complications of hypertension in pregnancy (5.09/1000 births) and spontaneous preterm labour (4.01/1000 births). Unexplained intrauterine deaths were the most common recorded primary obstetric cause of death in all areas. Complications of prematurity and hypoxia were the most common final causes of neonatal death in all groups.Conclusion. Intrapartum asphyxia, birth trauma, antepartum haemorrhage, complications of hypertension in pregnancy and spontaneous preterm labour account for more than 80% of the primary obstetric causes of death

A Comparative Study on the Energy Consumption of PHP Single and Double Quotes

This paper is an enhanced version of the paper presented at the SEEDS Conference (Olaoluwa, et. al, 2015). The increasing rate of carbon dioxide and other greenhouse gas emission resulting from the use of IT and other human activities to the atmosphere has become a major source of concern. It is imperative for the IT sector to ensure that its products are effective and energy efficient accompanied by mitigated negative impact on the environment. Reducing energy consumption of IT products is a key to contributing towards a greener environment. Another alternative is to produce energy efficient codes for software applications. In programming or scripting languages, an end result can be achieved in more than one way. For example, in PHP, a print command can be executed using a single quote and can also be achieved using a double quote. They have similar functions with similar quality of the intended outcomes. The aim of this research is conduct an investigation on the energy consumption of selected PHP scripts that perform similar functions: print single and double quote; echo single and double quote, etc… The Joulemeter energy measuring tool is used to measure the amount of energy consumed when run the various PHP scripts

A WEB-BASED ENVIRONMENTAL TOOLKIT TO SUPPORT SMES IN THE IMPLEMENTATION OF AN ENVIRONMENTAL MANAGEMENT SYSTEM

With small and medium sized-enterprises (SMEs) taking up the majority of the global businesses, it is important they act in an environmentally responsible manner. Environmental management systems (EMS) help companies evaluate and improve their environmental impact but they often require human, financial, and temporary resources that not all SMEs can afford. This research encompasses interviews with representatives of two small enterprises in Germany to provide insights into their understanding, and knowledge of an EMS and how they perceive their responsibility towards the environment. Furthermore, it presents a toolkit created especially for small and medium-sized enterprises. It serves as a simplified version of an EMS based on the ISO 14001 standard and is evaluated by target users and appropriate representatives. Some of the findings are: while open to the idea of improving their environmental impact, SMEs do not always feel it is their responsibility to do so; they seem to lack the means to fully implement an EMS. The developed toolkit is considered useful and usable and recommendations are drawn for its future enhancement

Sustainable and Green Information Systems: Preparing the next generation of practitioners.

Sustainable development and green computing issues are increasingly important for computing professionals. Preparing the next generation of implementers and developers requires that Higher Education providers develop curriculum to reflect this. There are a number of drivers behind this – encompassing industry and professional body demands, policy makers’ directives, as well as institutional commitments to sustainability. Other reasons include the effectiveness of this topic as a way to address particular issues in engagement and recruitment to computing courses. When considering “sustainability" or ("green-ness") in teaching, we should consider the appropriateness and suitability of material, and target it at an appropriate level. There are also choices about how to present the material so as to match students’ motivation, which can reflect gender and other demographic issues. Institutions can adopt different approaches, such as specialised courses as components of wider programmes, or as specialised courses in their own right. Some approaches integrate the topic into undergraduate teaching, treating environmental impact as a design constraint within a solution. This paper reports on some of these variations and directs readers to an online resource to enable colleagues interested in this topic to share ideas and approaches. Whilst the focus is on computing, many of the issues are transferrable to other STEM disciplines