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The Rockefeller Foundation shipped two Apple II computers with VisiCalc to the Tunisian Ministry of Agriculture to address a grain shortage in the early 1980s. The foundation believed that VisiCalc would enable the speedy and complex analytical modeling necessary to improve the management and, consequently, the production of grain resources. The foundation also argued that VisiCalc would empower individuals in the Ministry of Agriculture, improving their own analytical thinking as they became more familiar with the modeling capabilities of the software. Even with the use of VisiCalc, Tunisia experienced violent riots due to high bread prices after the government's removal of grain subsidies. This paper explores the narratives and uses of VisiCalc in the Tunisian Ministry of Agriculture in addressing this food crisis both before and after the riots. The work here contributes to computing history through an analysis of the historical relationships among governing bodies, nongovernment organizations, technology, and the global financial economy. It argues that the uses of VisiCalc in Tunisia were connected with financial austerity firmly aligned with Western interests. In doing so, this paper shows how a focus on postcolonial Africa can enrich the international history of computing. [ABSTRACT FROM AUTHOR]

In this paper, a tailoring process for a High Frequency Surface Wave Radar (HFSWR) transmitter antenna array is presented. The process is done in order to achieve optimal HFSWR performance in equatorial environments, defined by a low altitude coastline, frequent storms, and heavy rainfall which lead to frequent site flooding. Simultaneously, the price of the final design needed to be as low as possible in order to make it affordable for developing countries, since the majority of countries in the equatorial area fits in that category. Initially, the tailoring process was started with mathematical formulations, continued in EM simulation software, and then tested in the field. Based on the findings obtained during the tailoring process, the transmitting antenna arrays are installed and the HFSWRs are operationally used afterward. Final confirmation of the tailoring process presented in this paper came through everyday usage of the installed HFSWRs during a period that lasted several years in the Equatorial environment, namely the Gulf of Guinea. [ABSTRACT FROM AUTHOR]

Large dam projects (i.e., those exceeding 15 m) often make headlines for their poor performance and their negative social and environmental impacts. The world register characterizes dams by height, purpose (e.g., irrigation), and type (e.g., rock-fill). Thus, large dams differ in many technical ways, but because practitioners still lack a framework to sort them into different types for management purposes, they tend to manage them in a one-size-fits-all manner. Shenhar and Dvir's NTCP (novelty, technology, complexity, and pace) model (2007) may be a good fit as large dams experience high unforeseen technological uncertainty. In this paper, through observations, a case study, a qualitative analysis of 42 interviews with project managers, and a quantitative analysis, we examined 30 large dam projects in Africa and sorted them into different categories according to the NTCP model. Going beyond the rather static NTCP, we identified their underlying NTCP characteristics and the variety of roles that their project managers played throughout the lifecycle, and highlighted the dynamic fit between the roles and NTCP characteristics. Since different characteristics and project manager's roles are prominent at different phases, project managers should sort dams into different types based on the NTCP model at different phases, and tailor their roles accordingly for more success. [ABSTRACT FROM AUTHOR]

In this paper, we analyze the feasibility of applying the temperature and emissivity separation (TES) algorithm to thermal-infrared data acquired with three bands of the Spinning Enhanced Visible and Infrared Imager (SEVIRI) onboard the Meteosat Second Generation platform (SEVTES). The performance of the SEVTES algorithm was tested using data simulated over different atmospheric conditions and surface emissivities, with errors around 1.5% for emissivity and 1.5 K for temperature when atmospheric correction is accurate enough. In contrast, errors on land-leaving radiances higher than 2% or uncertainties on total atmospheric water vapor amount higher than 5% lead to errors on emissivity higher than 2% and errors on land surface temperature higher than 3 K, especially when the atmospheric absorption is overestimated. SEVIRI data acquired in August 2011 were also used to validate SEVTES emissivities against in situ measurements collected in five different homogeneous areas over Africa. Values were also intercompared to Moderate Resolution Imaging Spectroradiometer (MODIS)-derived and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER)-derived emissivities and to the LSA SAF emissivity product. Results show that SEVTES-derived emissivity values are consistent with MODIS-TES and ASTER-TES retrievals and that SEVTES also improves the retrievals included in LSA SAF and MOD11Cx v5 products. When compared to laboratory measurements, accuracies of around 1%-2% were obtained, although occasional inaccuracies (2%-3%) were also found in some cases at band 8.7 μm. The results presented in this paper show the potential SEVTES has for improving the LSA SAF product over arid and semiarid areas. [ABSTRACT FROM PUBLISHER]

The Japan Space Exploration Agency Kyoto and Carbon (K&C) Initiative seeks to demonstrate the potential of the Advanced Land Observing Satellite (ALOS) Phased Arrayed L-band Synthetic Aperture Radar (PALSAR) data for addressing regional applications relating to climate change, carbon cycle science, and environmental conservation. This paper outlines the generation of a regional dual-polarization (HH and HV) mosaic for the entire African continent at spatial resolution on the order of 100 m. The main computational and radar science issues undertaken to generate a seamless mosaic with good radiometric and geometric accuracy are summarized. Preliminary investigations into the thematic information provided by the K&C Africa mosaic and comparisons with the JERS-1 SAR mosaic generated as part of the Global Rain Forest Mapping Project are reported, with emphasis placed on characterizing and detecting change in forests and savannas. [ABSTRACT FROM AUTHOR]

Energy services are crucial to human wellbeing and development, and without reliable energy, it is difficult to escape subsistence lifestyles and poverty. Here, we report on four identical capacity rural minigrid interventions undertaken in Kenya and Uganda with differing socioeconomic characteristics and demographics. The research outcomes presented briefly discuss the preparation stages of the interventions including community surveys that informed the technical design, deployment phases, and setup of the community cooperatives to manage the minigrid projects. The main focus here is on lessons learned, including system design and minigrid performance under various load profiles. The results show a clear and increasing uptake of power by the communities with intensities varying depending on the electricity tariff used. Across the four minigrids, daily electricity growth rates are seen to vary by a factor of 8. The Ugandan minigrids operated at close to utility grid tariff and reached the 28-kWh/day design limit within two years. By contrast, the Kenyan minigrids charged a higher cost recovery tariff, which capped the demand and systems operate below the design limit. These findings have implications not only to system design but also to system stability and longevity. The approach taken here, of community centered cooperatives running the delivered minigrids, is now embedded within the rural electrification authorities/agencies in both countries, with additional similar projects being planned in 2019/2020. The application, ramifications, and replication of such a minigrid concept as compared to other approaches are also discussed in this paper. [ABSTRACT FROM AUTHOR]

When a significant event occurs, many news articles from different newsagents often report it. Moreover, these newsagents also provide platforms for their readers to write comments expressing their views or understanding. Through digesting these reader comments, we can gain insights into the reactions, suggestions, personal experiences, or public opinions with respect to the emerging event. However, these reader comments from different sources are often rapidly accumulated resulting in an enormous volume. It becomes difficult to manually analyze these comments. In this paper, we propose a framework that can digest reader comments automatically through latent event facets and news specificity. An event facet refers to the aspect of the event concerned by many readers. Specifically, some of the reader comments, despite coming from different sources, discuss a certain facet of the event. Such facets provide an effective means for organizing news comments in a global manner. On the other hand, some comments discuss the specific topic of the corresponding news article. These specific topics demonstrate the specific focus of readers on the piece of news locally. Such reader comment digest in different granularities facilitates readers deeper understanding of these enormous comments. To achieve the above desirable goal of digesting reader comments, we propose an unsupervised model called EFNS which is capable of capturing the intricate fine-grained associations among events, news, and comments. We also develop a multiplicative-update method to infer the parameters and prove the convergence of our algorithm. Our framework can also visualize reader comments according to the relationship with latent event facets and the degree of news specificity. Experimental results show that our proposed EFNS model can provide an effective way to digest news reader comments and outperform the state-of-the-art method. [ABSTRACT FROM AUTHOR]

Low-voltage, low-power solar photovoltaic (PV) based dc microgrids are becoming very popular in nonelectrified regions of developing countries due to lower upfront costs compared to utility grid alternatives and limited power needs of rural occupants. The optimal planning of distribution architecture along with sizing of various system components such as solar panels, batteries, and distribution conductors is essential for minimizing the system cost and enhance its utilization. In this paper, we develop a framework for optimal planning and design of low-power low-voltage dc microgrids for minimum upfront cost. The analysis is based on region-specific irradiance and temperature profiles; constraints in storage and distributions; distribution loss analysis; and optimum component sizing (storage, conductor, and PV panel) requirements based upon an energy balance model for a 24-h operation. We further analyze the merits of tailoring distribution architecture for maximizing the system utility in the planning of future microgrid deployments. [ABSTRACT FROM PUBLISHER]

In 2015, the United Nations (UN) launched an ambitious set of 17 Sustainable Development Goals (SDGs) to end poverty, protect the planet, and ensure prosperity for all as part of the 2030 Agenda for Sustainable Development. Achieving these far-reaching goals requires effective tracking of progress across 169 targets and over 230 indicators. Furthermore, adopted in 2015, Africa Agenda 2063 is a strategic framework developed by the African Union (AU) to optimize the use of the continent’s resources for sustainable and inclusive growth. It aims to deliver on key aspirations shared by African nations including a high standard of living, well-educated citizens, good governance, strong cultural identity, and Africa’s strong voice in global affairs. Built around 20 goals and seven priority areas, Agenda 2063 provides a shared vision and roadmap for socioeconomic transformation in Africa over the next 50 years. However, numerous countries in Africa face considerable challenges in collecting, timely, granular, high-quality data to adequately monitor SDG metrics. Traditional data sources like surveys and administrative records often have gaps, especially at subnational levels. As a result, national statistics offices, particularly in Africa, lack the data needed to properly inform SDG-related policies and interventions. [ABSTRACT FROM AUTHOR]

A rise in population, along with urbanization, has been causing an increase in demand for urban transportation services in the sub-Saharan Africa countries. In these countries, mobility of people is mainly ensured by bus services and a large-scale informal public transport service, which is known as paratransit (e.g., car rapides in Senegal, Tro Tros in Ghana, taxis in Uganda and Ethiopia, and Matatus in Kenya). Transport demand estimation is a challenging task, particularly in developing countries, mainly due to its expensive and time-consuming data collection requirements. Without accurate demand estimation, it is difficult for transport operators to provide their services and make other important decisions. In this paper, we present a methodology to estimate passenger demand for public transport services using cell phone data. Significant origins and destinations of inhabitants are extracted and used to build origin–destination matrices that resemble travel demand. Based on the inferred travel demand, we are able to reasonably suggest strategic locations for public transport services such as paratransit and taxi stands, as well as new transit routes. The outcome of this study can be useful for the development of policies that can potentially help fulfill the mobility needs of city inhabitants. [ABSTRACT FROM PUBLISHER]

Target 3.4 of the third Sustainable Development Goal (SDG) of the United Nations (UN) General Assembly proposes to reduce premature mortality from non-communicable diseases (NCDs) by one-third. Epidemiological data presented by the World Health Organization (WHO) in 2016 show that out of a total of 57 million deaths worldwide, approximately 41 million deaths occurred due to NCDs, with 78% of such deaths occurring in low-and-middle-income countries (LMICs). The majority of investigations on NCDs agree that the leading risk factor for mortality worldwide is hypertension. Over 75% of the world's mobile phone subscriptions reside in LMICs, hence making the mobile phone particularly relevant to mHealth deployment in Africa. This study is aimed at determining the scope of the literature available on hypertension diagnosis and management in Africa, with particular emphasis on determining the feasibility, acceptability and effectiveness of interventions based on the use of mobile phones. The bulk of the evidence considered overwhelmingly shows that SMS technology is yet the most used medium for executing interventions in Africa. Consequently, the need to define novel and superior ways of providing effective and low-cost monitoring, diagnosis, and management of hypertension-related NCDs delivered through artificial intelligence and machine learning techniques is clear. [ABSTRACT FROM AUTHOR]

Landscape degradation, soil depletion, scarcity of water and fuel resources are common threats to ecosystem services, agricultural production and human livelihoods in the developing world. Observatory or monitoring networks which focus on the dynamics of coupled human-natural systems are challenged by scarce data, data heterogeneity across multiple domains and spatial scales, and complex models required to produce meaningful sustainability indicators. An additional challenge is to visualize these complex data and indicators in a unified, easily understandable framework. This paper presents an environmental sustainability dashboard that integrates GIS data with household and plot surveys, field data and remote sensing imagery to compute a variety of metrics of ecosystem stress. The dashboard, a web-based decision support tool, is a key cyberinfrastructure component designed to satisfy the objectives of a Tanzanian agricultural and ecosystem services monitoring pilot. Based on this experience we discuss our framework and how it can be generalized for building decision support tools, and their associated cyberinfrastructure, for multi-scale, interdisciplinary monitoring networks. [ABSTRACT FROM PUBLISHER]

This paper shows how to reconstruct the original 275-m resolution data of the Multi-angle Imaging SpectroRadiometer (MISR) instrument in the 24 spectrodirectional global mode channels that are spatially averaged to 1.1 km on-board the Terra platform, with negligible loss of information relative to images acquired in native-resolution local mode. Standard approaches to improve the spatial resolution of products rely on one (typically panchromatic) high-resolution (HR) image to sharpen multiple spectral images. In the case of the MISR-HR package described here, three of the 12 available HR channels are combined to regenerate each of the 24 reduced-resolution channel to its native resolution. The accurate and rigorously reconstructed spectral bidirectional reflectance data allow sensitive and physically meaningful land surface attributes to be recovered at a spatial resolution appropriate to document the spatial heterogeneity of the land surface and relevant for climate and environment studies. MISR has been in continuous operation since February 2000 and provides global coverage in at most nine days (depending on latitude). This technique allows the generation of quantitative information to monitor change and model ecosystem function virtually anywhere and at any time during the last decade. The potential is demonstrated for a savanna landscape in South Africa. [ABSTRACT FROM PUBLISHER]

Differences in within-species phenology and structure are controlled by genetic variation, as well as topography, edaphic properties, and climatic variables across the landscape, and present important challenges to species differentiation with remote sensing. The objectives of this paper are as follows: 1) to evaluate the classification performance of a multiple-endmember spectral angle mapper (SAM) classification approach in discriminating ten common African savanna tree species and 2) to compare the results with the traditional SAM classifier based on a single endmember per species. The canopy spectral reflectance of the tree species ( Acacia nigrescens, Combretum apiculatum , Combretum imberbe, Dichrostachys cinerea, Euclea natalensis, Gymnosporia buxifolia, Lonchocarpus capassa, Pterocarpus rotundifolius, Sclerocarya birrea, and Terminalia sericea) was extracted from airborne hyperspectral imagery that was acquired using the Carnegie Airborne Observatory system over Kruger National Park, South Africa, in May 2008. This study highlights three important phenomena: 1) Intraspecies spectral variability affected the discrimination of savanna tree species with the SAM classifier; 2) the effect of intraspecies spectral variability was minimized by adopting the multiple-endmember approach, e.g., the multiple-endmember approach produced a higher overall accuracy (mean of 54.5% for 20 bootstrapped replicates) when compared to the traditional SAM (\mean overall accuracy = 20.5\%); and 3) targeted band selection improved the classification of savanna tree species (the mean overall percent accuracy is 57% for 20 bootstrapped replicates). Higher overall classification accuracies were observed for evergreen trees than for deciduous trees. [ABSTRACT FROM AUTHOR]

The leakage current on heavily polluted silicone rubber insulators is usually smaller than on similarly polluted porcelain insulators. In this paper, results are presented that show that under light contamination, the currents on the two types of insulators can have similar values. Results are also presented from two different sites that show that under certain conditions the currents on silicone insulators can be higher than on porcelain. The phenomenon is explained, referring to the superior washability of the porcelain and moisture absorption of the pollution layer on the silicone rubber insulators during times of high humidity. [ABSTRACT FROM AUTHOR]

In this paper, we describe our approach of using value-sensitive design to guide the design, development, and implementation of health information systems for use in rural areas of two developing countries in Africa. By using shared conceptual investigation, we are able to create a generalized list of stakeholders and values that span multiple projects without losing any of the power of the conceptual investigation. This process can be applied to other projects to develop a stronger set of stakeholders and values. We also present a technical investigation of a vaccine delivery project in Sub-Saharan Africa and plans for an upcoming empirical investigation for a mobile-phone-based support tool for community health workers in East Africa. [ABSTRACT FROM AUTHOR]

Land-based transport corridors serving landlocked developing countries experience cargo delays that are much longer than global benchmarks, reducing the competitiveness of the affected countries within an increasingly globalized economy. Improving the efficiency of such corridors is complicated by the inefficient management of border crossings. Factors contributing to long border delays include the variability of vehicle processing times and lack of sufficient capacity at service desks during peak traffic periods. We use a simulation approach to investigate improvements to current border management systems by modeling each important aspect of the cross-border process. The simulator was calibrated against data collected during cross-border surveys. This article is the first to quantify the potential for reduction in border delays through the reduced variability of process times. A dynamic adjustment model was developed to enable an optimal compromise between the number of service desks for each process; utilization levels of the available capacity; and average delay time. The novelty of our approach lies in the fact that service capacity adjustments are based on data that are collected inside the border area, rather than data that are collected from traffic in transit to the border, which is much easier to implement in practice. [ABSTRACT FROM AUTHOR]

New and emerging technologies have recently taken center stage in public policy debates around the world. From the European Union’s (EU) Artificial Intelligence (AI) Act and the Council of Europe’s (CoE) treaty process to soft laws introduced by the Organization for Economic Cooperation and Development (OECD) and a proposal for a bill of rights in the United States , new and emerging technologies have galvanized policymaking at various levels. An overarching objective in such legislative initiatives is upholding human rights not only in the operationalization, but also in the conception and design of new and emerging technologies. But much of the recent legislative and policy initiatives are occurring in the Global North. Partly due to the low uptake of new and emerging technologies, similar initiatives are yet to proliferate in the Global South. In the few jurisdictions where such initiatives exist, one sees clear marks of the regulatory initiatives in the Global North. In Egypt, for instance, a national AI strategy developed based on the international benchmarks mentioned above has recently been tabled. Other countries in Africa have introduced rather generic digital transformation strategies. At the regional level, the African Union appears to pursue two parallel processes aimed at developing a continental AI strategy for Africa in which the influence of AI initiatives from the Global North is inevitable ,. [ABSTRACT FROM AUTHOR]

This article presents a brief background of the personal computer boom in Lagos, including the early history of computing and the rise of technology entrepreneurship in Nigeria. I then discuss the impact of Nigeria's structural adjustment program on the expansion of the local computing industry. Next, I detail the landscape of Nigerian personal computer boom in late 1980s and 1990s and discuss how innovative technologists drove the industrial and societal expansion of computer use in Nigeria by responding to the demands of global capital and state economic policies. Finally, I explore the reasons behind the eventual decline of the personal computer boom and examine its impact on Nigerian information technology, particularly focusing on relationships between the political and socioeconomic environment and broader industry changes. [ABSTRACT FROM AUTHOR]

The HelioClim-1 database contains daily values of the solar radiation reaching the ground. This GEOSS (Global Earth Observation System of Systems) Data Collection of Open Resources for Everyone (Data-CORE) covers Europe, Africa and the Atlantic Ocean, from 1985 to 2005. It is freely accessible at no cost through the SoDa Service (xlink:type="simple" xlink:href="www.soda-is.com" xmlns:xlink="http://www.w3.org/1999/xlink"www.soda-is.com). Several assessments of the HelioClim-1 data against measurements made in meteorological networks reveal that the HelioClim-1 database offers a reliable and accurate knowledge of the solar radiation and its daily, seasonal and annual variations over recent years. The HelioClim-1 data may help in qualifying in situ measurements and may supplement them, thus offering 21 years of accurate daily means of surface solar irradiance. Several published works benefited from openness, availability and accuracy of the HelioClim-1 database in various domains: oceanography, climate, energy production, life cycle analysis, agriculture, forestry, architecture, health and air quality. This demonstration of the benefit of the HelioClim-1 database draws attention to resources open to everyone such as those labeled GEOSS Data-CORE. [ABSTRACT FROM PUBLISHER]

The 2016 Instrumentation and Measurement Society's (IMS) annual Strategic Planning Meeting, in which the Society officers and the Editors-in-Chief (EICs) participated, was held in Atlanta, GA during February 18-20. The opening remarks by Ruth Dyer, President, emphasized the importance of Vision, Mission and Goals as the IMS seeks to identify initiatives to pursue that will benefit our members. Our plans must stay aligned with our overall goals so that we make the most effective use of our resources. Our financial resources are important, but one most crucial resource that we have is the invaluable time voluntarily given by the IMS Officers, AdCom members, and active general members, all of whom work diligently to advance our Society goals. Ruth reminded the group of the upcoming comprehensive publications and Society review by the IEEE, which will take place in 2017. She challenged us to continue analyzing the recent IEEE membership survey results for ideas which would improve the value of our services to our members. Ruth's message focused on both the initiatives being undertaken by IEEE and those by the IMS AdCom. She encouraged us to continue our efforts to improve our already highly and effective Society. [ABSTRACT FROM PUBLISHER]

This paper discusses the challenges and opportunities facing the development of hydroelectric power in Africa. [ABSTRACT FROM PUBLISHER]

Globally, the importance of sustainable development is recognized due to a number of interconnected social, environmental, and economic challenges. One of the key tenets of sustainable development is the introduction of clean energy, and specifically renewable energy technologies (RETs). To accelerate the adoption of RETs, however, requires the rate of commercialization of such technologies to increase; classified as multitechnology renewable energy systems (MTRESs) due to the hierarchical nature of such systems, with differing commercialization-based needs. A strategic management framework was subsequently developed as a means to support the establishment of strategies for increasing the commercialization rate of MTRESs, and applied to the case of concentrating solar power in South Africa. The framework serves as a proof-of-concept, given the current industry constraints due to political uncertainties in the energy sector of the country, as well as the type of validation process followed, with the framework yet to be practically implemented. This article encourages dialogue on how different stakeholders may be mobilized in the interests of a given technology, while continuing a recent trend in literature, which seeks to move the conversation from energy analysis to practical measures, aimed at hastening efforts towards a sustainable energy transition. [ABSTRACT FROM AUTHOR]

The livelihood of smallholder farmers in emerging economies’ cocoa supply chain is substandard because of fraud, exploitation, corruption, deceit, child labor, and financial exclusion, usually perpetrated by influential actors. This situation creates a social sustainability problem which needs urgent attention. Digital technologies such as sensors, drones, satellites, and blockchain show promise toward fostering social sustainability deep into the supply chain. This innovation is consistent with the United Nations 2030 sustainable development goals of transforming world economies toward a more sustainable future vision by reducing poverty and inequality. As our contribution, we adopt a traditional approach in our perspective article to initiate a scholarly curiosity to discuss and develop research needs on how to use technology to address this current and critical sustainability and supply chain concern. Blockchain can solve the inefficiencies, complexities, and other social issues of smallholder farmers in the supply chain. This article identifies some blockchain technologies in emerging economies, such as Hara Technology in Indonesia and Cellulant Agrikore Blockchain Solution in Nigeria. Again, we observed that the promise of using technology to improve smallholders' vulnerability in the cocoa supply chain remains underexploited in Africa and other emerging economies. Therefore, rigorous research on smallholders' social sustainability is needed to make sound policy recommendations. This short perspective article describes issues facing these smallholder farmers and how technology can play a role for them and their supply chains to alleviate various social and environmental concerns. Accordingly, we propose some research questions for technology, innovation, and engineering management researchers. [ABSTRACT FROM AUTHOR]

Inefficient healthcare is a major concern among many African nations. It can be mitigated by building world-class infrastructure connecting different medical facilities for collaboration and resource sharing. Such infrastructure should support the exchange of medical data, enabling access to expertise not available locally. It should be equipped with technologies of the fourth industrial revolution, providing support to doctors thereby enabling African nations leapfrog from poorly equipped to medically prepared. Sadly, world-class healthcare facilities are a missing piece in African public health ecosystems. Medical facilities are either non-existent or prohibitively expensive. Being a collaborative model between Cloud providers, federated Clouds allow the execution of tasks on computing resources flexibly and cost efficiently. This paper aims to interconnect medical facilities across Africa by proposing a Cloud federation for healthcare using co-operative and competitive collaboration models. Simulations were carried out to test the efficiency of these models using two new allocation schemes: Genetic Algorithm-based VM Allocation (GAVA) and Stable Roommate Allocation (SRA). These schemes were bench-marked against First-Fit-Descending (FFD), Best-Fit-Descending (BFD), Binary-Search-Best-Fit (BSBF) allocation schemes; for both light and heavy workloads. Obtained results revealed that the co-operative model resulted in lower delays but higher resource utilization; while the competitive provided faster service delivery and better quality of service. Deployment considerations and potential business models for the African Cloud federation were also presented.

This study uses mobile phone data to understand mobility patterns in a country, with limited mobility data, in order to give advice about decisions on how to design the national and regional road network. Our method consists of three parts: (1) filtering mobile phone traces to derive mobility patterns, (2) building an adapted formulation of the gravity-based trip distribution model, which considers telecommunication intensity (i.e., aggregate number of calls and text messages) and travel time as input to forecast the influence of road improvements on country-wide mobility, and (3) optimizing the road network investment based on the adapted trip distribution model by using a local search algorithm. The method was applied to the case study country of Senegal. The mobile phone data was transformed to support informed decisions on road network development in that country given different objectives, namely accessibility and equity. We believe that the methodology is valuable and reproducible to other countries where traditional mobility data is scarce but mobile phone data is available to transport planners. [ABSTRACT FROM AUTHOR]

Vast geographical distances in Africa are a leading cause for the so-called digital divide due to the high cost of installing fiber. Free-space optical (FSO) communications offer a convenient and higher bandwidth alternative to point-to-point radio microwave links, with the possibility of repurposing existing infrastructure. Unfortunately, the range of high-bandwidth FSO remains limited. While there has been extensive research into an optimal mode set for FSO to achieve maximum data throughput by mode division multiplexing, there has been relatively little work investigating optical modes to improve the resilience of FSO links. Here, we experimentally show that a carefully chosen subset of Hermite–Gaussian modes is more resilient to atmospheric turbulence than similar Laguerre–Gauss beams, with a predicted upper bound increase in propagation distance of 167% at a mode-dependent loss of 50%. [ABSTRACT FROM AUTHOR]

Introduction: Under the influence of economic globalization, many enterprises are seeking more markets in developing countries, and more Chinese business expatriates are being sent to work in host countries. This study explores Chinese business expatriates’ communication experience and identity work in three African countries, and their perceptions of the functions of English or the local language in transnational business communication. About the case: This article explores the following research questions: 1. How do Chinese business expatriates experience their cultural and national identity when using a foreign working language in a host country? 2. How do Chinese business expatriates evaluate the functions of a foreign language in their transnational communication? 3. What suggestions can be provided for future business expatriates and their transnational/globalizing companies? Situating the case: The process of identity construction and business expatriates’ identity work in a host space are interpreted in the context of Hofstede and Hofstede's acculturation curve. Other key concepts related to transnational business communication, including third space as defined by Bhabha, are also addressed. Methods/approach: Using a case study approach, the researchers examine four participants’ transnational business communication experiences and interpret their identity work through the data collected in the form of interviews. Results/discussion: The researchers find that the business expatriates realized the importance of English or local language communication competence in a transnational business space, although they still kept their Chinese cultural and national identity. Conclusions: This study contributes to transnational business communication by helping professionals to understand the language and cultural challenges faced by Chinese business expatriates, and offers suggestions for globalizing companies that send employees to host countries. [ABSTRACT FROM AUTHOR]

This study focuses on the role that African dust over the Atlantic had on the persistence of the tropical system that eventually became Hurricane Sandy in October 2012. On October 8, a Saharan dust event in the Mauritania region of West Africa transported significant amounts of mineral dust into the troposphere and along the path of an easterly wave created by a break in the Intertropical Convergence Zone (ITCZ). The Terra/Aqua-MODIS satellite observations clearly define the spatial distribution of the coarse/fine aerosols, while the CALIPSO observations of the total attenuated backscatter at 532 nm provide a detailed view of the vertical structure and aerosol types in the dust-laden layer. European Centre for Medium-Range Weather Forecasts and Modern-Era Retrospective Analysis for Research and Applications, Version 2 reanalysis data show the distribution of aerosols along the path of the pre-Sandy wave as well as a second wave that formed north of the ITCZ under different condition. The second wave, which started in an area of relatively larger aerosol optical depth (AOD), moved into an area with abnormally low convective available potential energy and AOD, subsequently dying out, while the wave that became Sandy had light aerosol loading (AOD between 0.15–0.5) along a majority of its path. The evidence suggests that aerosols played a nontrivial role in the maintenance of this system until it moved into an environment favorable for cyclogenesis. [ABSTRACT FROM PUBLISHER]

The global spread of Internet and mobile communications has been accompanied by a growing interest in how information and communication technologies (ICTs) can contribute to social and economic development. There are a considerable number of such examples in developing countries. For example, M-Pesa in Kenya allows workers in the cities to send money back to families living in the countryside using SMS messages on basic mobile phones. In Ghana, the Motech project allows community health workers to use feature phones and network services to track ante-natal (and post-natal) care with the objective of improving outcomes for both mothers and babies. Other examples include Gram Vaani's (GRINS) open-source software for community radio stations, or Ushahidi's initiatives, which began with tracking post-electoral violence in Kenya in 2008 using mobile phones and Google maps. These examples illustrate different ways of leveraging ICT to improve lives and livelihoods worldwide. Such stories are inspiring many young (and not so young) researchers and innovators alike to explore how technology might support social and economic development and inclusion in global knowledge exchange. [ABSTRACT FROM AUTHOR]