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Green roofs are strategies for the ecological intensification of cities and a measure of meeting some of the sustainable development goals (SDGs). They have widely been adopted as an adaptation strategy against an urban heat island (UHI). However, they are conventionally soil-based making it difficult and expensive to adopt as a strategy for greening existing buildings (GEB). This paper, therefore, develops a novel green roof system using climbers for thermal-radiative performance. The paper explores the vitality of climbing species as a nature-based strategy for GEB, and for the ecological improvement of the predominantly used cool roofs in sub-Saharan Africa (SSA).

Simulation for the same building Kejetia Central Market (KCM) Redevelopment; the existing aluminium roof (AL), soil-based extensive green roof (GR1) and the proposed green roof using climbing plants (GR2) were performed using ENVI-met. The AL and GR1 were developed as reference models to evaluate and compare thermal-radiative performance of the conceptual model (GR2). The long wave radiation emission (Q_lw), mean radiant temperature (MRT) and outdoor air temperature (T_a) of all three roofing systems were simulated under clear sky conditions to assess the performance and plant vitality considering water access, leaf temperature (T_f) and latent heat flux (LE₀) of GR1 and GR2.

There was no short wave radiation (Q_sw) absorption at the GR2 substrate since the climbers have no underlying soil mass, recording daily mean average Q_lw emission of 435.17 Wm⁻². The soil of GR1, however, absorbed Q_sw of 390.11 Wm⁻² and a Q_lw emission of 16.20 wm⁻² higher than the GR2. The AL recorded the lowest Q_lw value of 75.43 Wm⁻². Also, the stomatal resistance (r_s) was higher in GR1 while GR2 recorded a higher average mean transpiration flux of 0.03 g/sm³. This indicates a higher chance of survival of the climbers. The T_a of GR2 recording 0.45°C lower than the GR1 could be a good UHI adaptation strategy.

No previous research on climbers for green roof systems was found for comparison, so the KCM project provided a unique confluence of dynamic events including the opportunity for block-scale impact assessment of the proposed GEB strategy. Notwithstanding, the single case study allowed a focussed exploration of the novel theory of redefining green roof systems with climbers. Moreover, the simulation was computationally expensive, and engaging multiple case studies were found to be overly exhaustive to arrive at the same meaningful conclusion. As a novelty, therefore, this research provides an alternative theory to the soil-based green roof phenomenon.

The thermal-radiative performance of green roofs could be improved with the use of climbers. The reduction of the intensity of UHI would lead to improved thermal comfort and building energy savings. Also, very little dependence on the volume of soil would require little structural load consideration thereby leading not only to cheaper green roof construction but their higher demand, adoption and implementation in SSA and other low-income economies of the global south.

The reduction of the consumption of topsoil and water for irrigation could avoid the negative environmental impacts of land degradation and pollution which have a deleterious impact on human health. This fulfils SDG 12 which seeks to ensure responsible consumption of products. This requires the need to advance the research for improvement and training of local built environment practitioners with new skills for installation to ensure social inclusiveness in the combat against the intractable forces of negative climate impacts.

Climbers are mostly known for green walls, but their innovative use for green roof systems has not been attempted and adopted; it could present a cost-effective strategy for the GEB. The proposed green roof system with climbers apart from becoming a successful strategy for UHI adaptation was also able to record an estimated 568% savings on topsoil consumption with an impact on the reduction of pollution from excavation. The research provides an initial insight into design options, potentials and limitations on the use of climbers for green roofs to guide future research and experimental verification.

Modern wireless communication application requires an antenna system to meet the requirements of miniaturization and wideband characteristic. In recent years, several antenna designs, that meet these requirements, have been proposed in the literature. In this context, the purpose of this paper is to design a new microstrip monopole antenna with a bandwidth enhancement and size reduction for ultra wideband application.

The patch, of leaf of a plant shape, the feed line and the ground plane are printed on the inexpensive FR4 substrate material with permittivity 4.4 and loss tangent 0.02. To obtain optimal dimensions, a parametric study is conducted through numerical computations by using electromagnetic simulators HFSS and CST. A prototype of the optimized antenna is fabricated and subjected to a series of simulations and measurements.

The measurement results show a −10 dB impedance bandwidth of 6.7 GHz (3.5 GHz-10.2 GHz) which can cover the whole bandwidth requirements of an ultra wideband application. The designed antenna exhibits nearly symmetric and omnidirectional radiations patterns over the operating band, which is a sought-after behavior in microstrip patch antennas and has overall size of 35 × 31 mm².

The proposed microstrip monopole antenna is very useful for modern wireless communications systems because of its compact size, its capability of covering the whole ultra wideband frequency band and its good radiation characteristics.

Although conformable devices are commonly designed to couple with the human body for personalized and localized medicine, their applications are expanding rapidly. This paper aims to delineate this expansion and predict greater implications in diverse fields.

Today’s device technologies continue to face fundamental obstacles preventing their seamless integration with target objects to effectively access, evaluate and alter self-specific physical patterns, while still providing physical comfort and enabling continuous data collection. Due to their extreme mechanical compliance, conformable devices permit the query of signals occurring at interfaces so as to decode and encode biological, chemical and mechanical patterns with high resolution, precision and accuracy. These unique and versatile capabilities allow for a marked change in the approach to tackling scientific questions, with the ability to address societal challenges at large.

Here, this study highlights the current state of these devices in a wide range of fields, such as interactive teaching, textiles, robotics, buildings and infrastructure, agriculture, climate and space, and further forecasts essential features of these devices in the near future.

This study justifies conformable devices’ growing utility through a novel quantitative analysis methodology that indexes peer-reviewed journal articles based on specific keywords, whereby this study tracks keyword frequency over time across specific fields in conjunction with conformability-like topics. The resulting trends’ trajectories provide the foundation for this study’s future projections. This study concludes with a perspective on the possible challenges concomitant with a ubiquitous presence of these technologies, including manufacturing, wireless communication, storage, compression, privacy and sharing of data, environmental sustainability, avoidance of inequality and bias and collaboration between stakeholders at all levels of impact.

The purpose of this paper is to describe an AI (Artificial Intelligence) that can “think like an African traditional doctor”. The system proposes to model and to use attitudes taken and concepts used by African traditional doctors when facing cases. It is designed to go deep into the concepts of African traditional medicine (ATM) by dealing with all the possible interpretations of those concepts, and to produce more much satisfying and accurate support for medical diagnosis and prescription than existing systems.

To take into account the sometimes strange concepts used and attitudes taken by African traditional healers, including mystical considerations, the system relies on a deep ontology describing all those concepts and attitudes in a more computer readable manner allowing a multi-agent system to have full access to ATM knowledge. Ethnological inquiries, literary analysis and interviews of traditional doctors (the holders of African medicine knowledge) were performed to gather sufficient data to achieve the work.

The paper addresses this question of how to build a practical large-scope computer-aided diagnosis and prescription system which can exploit deep descriptions of ATM concepts, including mystical considerations. The system also provides scientific interpretations to some concepts sometimes considered as mystical facts. It is a java web-based platform combined to a Java Agent Development framework multi-agent system accessing an ontology to provide its results.

Because of the origins of healers involved in this research (from Gabon and Cameroon, countries of Central Africa), the ontology and the collected data may lack generalizability in the African scope and then it is a prototype. Therefore, ATM experts all over the continent are encouraged to participate to improve and standardize the ATM ontology and to populate the knowledge base. On the other side, the system cannot give scientific explanations to all the mystical considerations in ATM, there still some facts which cannot be rationally explained for now.

The paper demonstrates the practical usability of the implemented system on the diagnosis and the treatment of a patient case.

The research describes a system which once validated by traditional experts, will serve as a tool to assist them in their day-to-day diagnosis and prescription tasks and will also serve as a reference on ATM practices for all interested users.

The paper provides an in-depth description of a computer-aided diagnosis system (CADS) that promotes indigenous technology from an African perspective. Comparing to the former systems identified in the literature, the proposed system is the first which deals with believes and mystical considerations in ATM, and also the first which provides a function to rank its results.

This chapter will outline the theory behind collaborative learning environments and describe several projects that best exemplify these theories and how best to incorporate them into the learning styles of the Net Generation's way of learning. Through partnerships with the St. Louis science center and the Children's Museum of Manhattan, visuality and interactivity have been incorporated into displays that demonstrate how these sorts of projects encourage students to collaborate in different ways as well as how teachers can introduce material in a variety of multidisciplinary formats.

Structural engineering as a part of civil engineering has over 5,000 years of distinguished history, as documented in this paper. An attempt is made in this paper to define structural engineering as it exists at present, then some historical structures are identified.

The advances of structural engineering are discussed in chronological order, encompassing the development of the concept, analysis, the use of innovative construction materials, and construction. The developments which necessitated the change of design philosophies are presented, and the current status of structural engineering is discussed in terms of several specific topics. Opportunities and challenges in the new millennium in structural engineering are then presented in terms of education, service to society, and research.

In the past, structural engineering always met the challenges it faced. It helped to improve our quality of life, and its role in society is not expected to change in the near future.

The paper has provided an over‐view of this important profession – from ancient history to the present day. Based on research over several decades it offers a prediction of the direction in which this profession and the academic research that underpins it is likely to take in the future.

The purpose of this paper is to provide a comprehensive review on the academic journey of artificial intelligence (AI) in agriculture and to highlight the challenges and opportunities in adopting AI-based advancement in agricultural systems and processes.

The authors conducted a bibliometric analysis of the extant literature on AI in agriculture to understand the status of development in this domain. Further, the authors proposed a framework based on two popular theories, namely, diffusion of innovation (DOI) and the unified theory of acceptance and use of technology (UTAUT), to identify the factors influencing the adoption of AI in agriculture.

Four factors were identified, i.e. institutional factors, market factors, technology factors and stakeholder perception, which influence adopting AI in agriculture. Further, the authors indicated challenges under environmental, operational, technological, economical and social categories with opportunities in this area of research and business.

The proposed conceptual model needs empirical validation across countries or states to understand the effectiveness and relevance.

Practitioners and researchers can use these inputs to develop technology and business solutions with specific design elements to gain benefit of this technology at larger scale for increasing agriculture production.

This paper brings new developed methods and practices in agriculture for betterment of society.

This paper provides a comprehensive review of extant literature and presents a theoretical framework for researchers to further examine the interaction of independent variables responsible for adoption of AI in agriculture.

The peer review history for this article is available at: https://publons.com/publon/10.1108/OIR-10-2020-0448

A regular feature giving news and comments on events and productions in the field of visual aids for technical and scientific teaching and training

The automatic visual sensing of aerosol sprays has many advantages over alternative techniques. This article suggests various measurements which could form the basis of an inspection system and illustrates their use on sprays produced by a can of furniture polish. The extension of these ideas to other applications is also discussed.