Proceedings of the African Diaspora Conference on Sustainable Development

The authors urge the Western donor organizations to facilitate and support the take up of such more sustainable models

Block Analysis for the Calculation of Dynamic and Static Length Scales in Glass-Forming Liquids

We present {\it block analysis}, an efficient method to perform finite-size scaling for obtaining the length scale of dynamic heterogeneity and the point-to-set length scale for generic glass-forming liquids. This method involves considering blocks of varying sizes embedded in a system of a fixed (large) size. The length scale associated with dynamic heterogeneity is obtained from a finite-size scaling analysis of the dependence of the four-point dynamic susceptibility on the block size. The block size dependence of the variance of the $\alpha$-relaxation time yields the static point-to-set length scale. The values of the obtained length scales agree quantitatively with those obtained from other conventional methods. This method provides an efficient experimental tool for studying the growth of length scales in systems such as colloidal glasses for which performing finite-size scaling by carrying out experiments for varying system sizes may not be feasible.Comment: 5 pages, 3 figure

W-Band GaAs HEMT MMIC Subharmonically Pumped Diode Mixers with 20 GHz IF Bandwidth

Two subharmonically pumped (SHP) diode mixers are designed for wideband W-band RF frequencies, fixed LO frequency operation. These mixers are fabricated on a 4-mil substrate using 0.1- µµµµm GaAs MMIC process. Both simulation and test results show that the mixers are with 12.25 and 11.75 dB average conversion losses, respectively. Both mixers have IF bandwidth wider than 20 GHz. The conversion loss flatness of the symmetric circuit is within ±1.25 dB. To our knowledge, these are the state-of-the-art result on low-conversion-loss wideband MMIC SHP diode mixers

Glass Transition in Supercooled Liquids with Medium Range Crystalline Order

The origins of rapid dynamical slow down in glass forming liquids in the growth of static length scales, possibly associated with identifiable structural ordering, is a much debated issue. Growth of medium range crystalline order (MRCO) has been observed in various model systems to be associated with glassy behaviour. Such observations raise the question about the eventual state reached by a glass former, if allowed to relax for sufficiently long times. Is a slowly growing crystalline order responsible for slow dynamics? Are the molecular mechanisms for glass transition in liquids with and without MRCO the same? If yes, glass formers with MRCO provide a paradigm for understanding glassy behaviour generically. If not, systems with MRCO form a new class of glass forming materials whose molecular mechanism for slow dynamics may be easier to understand in terms of growing crystalline order, and should be approached in that manner, even while they will not provide generic insights. In this study we perform extensive molecular dynamics simulations of a number of glass forming liquids in two dimensions and show that the static and dynamic properties of glasses with MRCO are different from other glass forming liquids with no predominant local order. We also resolve an important issue regarding the so-called Point-to-set method for determining static length scales, and demonstrate it to be a robust, order agnostic, method for determining static correlation lengths in glass formers

GIS-based locational analysis of petrol filling stations in Kaduna Metropolis

Location of environmental sensitive commercial and service activities in densely populated urban areas are guided by planning principles and standards, expressed in either structure plans or land use development plans. There has been an upsurge of filling stations within Kaduna metropolis thereby raising the questions about their certified locations. This study analysed the location of filling stations in Kaduna Metropolis against the physical planning standards set by Department of Petroleum Resource (DPR) and Kaduna Urban Planning and Development Agency (KASUPDA). Names and addresses of the filling stations were obtained from the Department of Petroleum Resource (DPR) Kaduna. Global Positioning System (GPS) Garmin 78s map was used to capture the locations of the filling stations. The findings revealed that there are 228 filling stations located along the 26 roads in the study area, of which 74% are owned by independent marketers, 18% owned by Major Marketers and 8% owned by the NNPC. There is significant correlation between the number of filling stations and the road hierarchy. However, 86% of the filling stations did not meet the minimum distance of 100 meter from the health care facilities. 84% did not meet the criteria of 400 meter minimum distance to other stations where located on same road side. The research recommends that the regulatory agencies should take appropriate measures to ensure that filling stations operators comply with the standards.Keywords: GIS, Analysis, Petrol, Filling Station, DPR, Kaduna metropoli

Cyber Security: Detection of Malicious Insiders for the Financial Benefit of Côte d\u27Ivoire

According to ‘Croissance Afrique’, a local magazine, the annual economic impact of cybercrime in Cote d\u27Ivoire is estimated to be 10 million dollars per year (2022). Furthermore, cybercrime is a costly issue in Cote d’Ivoire and the country is included in the list of countries with poor cyber security. Cybercrime affects not only the country but also has a worldwide impact. Improving cyber security will have a positive economic impact on the country

Space-centred information management approach to improve CAD-based healthcare building design

This study focuses on developing a space-centred CAD tool to enable designers to effectively manage and implement the information of design guidance information and user requirements during design processes, especially for the stages of design briefing and conceptual design. It aims to structure and store design guidance and user requirements for healthcare building design into a relational database, and link them to relevant space entities in design plans. The tool is developed on the platform of Autodesk Architecture Desktop (ADT). It also enables users to store and retrieve pictures associated with textual information, because pictures have been always used by designers as an effective medium to represent and deliver design information and knowledge. This can give users directly visual and more understandable perceptions of the design guidance. The tool is fully embedded with Autodesk AutoCAD systems to ensure the application of this tool being fully merged with CAD-based design process. A set of design guidance about Alzheimer clinic built environments are adopted as a sample to demonstrate and validate the tool. Moreover, the scenario of expanding this application to more broad areas has also been foreseen