Connecting the dots in infrastructure development and management: The Africa agenda for new innovation

It is widely accepted that the growth and prosperity of nations is dependent on economic infrastructure. Infrastructure is constituted by cyber-physical systems that enable communications (e.g. postal, telephone and internet) as well as transportation (e.g. road, water, air), energy (e.g. electricity and gas) and other utilities (e.g. drinking water and waste) (Chandler, 1977; NAO, 2013). It provides the basis for economic growth and prosperity through the provision of essential services that enable economic and social activity. As a result, it delivers significant benefits, both directly through the services it delivers, and indirectly through the impact of those services on the rest of the economy (Nightingale et al 2016). However, these benefits come at a cost. Infrastructure is expensive to build, operate and maintain. The provision of infrastructure involves degradation and the consumption of natural ecosystems, displacement of local communities, CO_{2} emissions, noise and pollution. Infrastructure is typically long-lived and the costs of poor choices and mistakes can affect future generations. This is especially prominent with politically motivated infrastructure investment decisions, which have a lifespan that coincides with electoral cycles. To complicate matters further, the costs and benefits of infrastructure provision fall unequally across society in a way that benefits a minority (usually local to the area of infrastructure development) although the distribution of costs are more widely spread (for example in investments funded by taxes) (ibid). In this context, infrastructure investment decisions are not only complex they are inherently political

hiPSC-derived hepatocytes closely mimic the lipid profile of primary hepatocytes: A future personalised cell model for studying the lipid metabolism of the liver

Peer reviewe

Improving EGM2008 by GPS and leveling data at local scale

The development of the Earth Gravitational Model 2008 (EGM2008) model is a significant contribution for modeling the Earth's gravity and geoid. Recently, it can be confidently used versus geometric models following a simple refinement procedure. Several studies show that, EGM2008 can reach the accuracy of regional or local geoid models after modeling the differences between the GPS-leveling geoid heights and EGM2008 derived geoid heights at identified control points. The study focuses on a corrector surface fitting (CSF) approach based on radial basis functions (RBF) as improvement procedure for EGM2008. A detailed mathematical model and solution algorithm of the proposed model is given, and it has been applied in different test areas covering the city borders of Bursa, Konya, Denizli and Gaziantep in Turkey. Accuracy of the improved model was evaluated in scattered check points within test regions. The geoid heights of all check points obtained by GPS-leveling measurements were compared with the geoid heights obtained from improved model. The discrepancies between the calculated and measured geoid heights were analyzed and discussed

Rede geodésica para o monitoramento costeiro do litoral setentrional do estado do Rio Grande do Norte

Este trabalho apresenta os procedimentos técnicos envolvidos na implantação da Rede GPS do Litoral Setentrional do Rio Grande do Norte (RGLS), onde o objetivo é fornecer subsídios fundamentais aos levantamentos geodésicos destinados ao monitoramento de áreas costeiras, submetidas à intensa dinâmica e de grande importância socioeconômica e ecológica para o Estado do Rio Grande do Norte. A metodologia permitiu a determinação das coordenadas geodésicas e altitudes ortométricas das estações com precisão decimétrica em relação ao Sistema Geodésico Brasileiro (SGB), a partir do método de posicionamento relativo e da altimetria por GPS. Ainda, foi possível o estudo de aspectos geodésicos envolvidos na altimetria por GPS, tais como avaliação da situação física e da densidade das Referências de Nível (RRNN) disponíveis, avaliação absoluta e relativa do modelo geoidal, proposição de metodologia para a altimetria por GPS de precisão e desenvolvimento de software para essa finalidade, que contribuíram para o conhecimento geodésico na área de estudo

Determinação de função covariância local para a predição de anomalias da gravidade Bouguer e valores da gravidade visando à obtenção de números geopotenciais

Considerando as dimensões de um país como o Brasil, realizar observações gravimétricas sobre todas as linhas de nivelamento do país ainda constitui-se um problema pertinente quando o objetivo é a determinação de números geopotenciais e/ou quantidades relacionadas ao campo da gravidade (e.g. anomalias da gravidade). Funções de covariância locais foram construídas a partir de valores da gravidade disponibilizados pelo Instituto Brasileiro de Geografia e Estatística (IBGE). Estes valores foram digitalizados e anexados à base de dados do Laboratório de Referenciais Geodésicos e Altimetria por Satélites (LARAS) da UFPR, a qual já contém dados da rede gravimétrica argentina. Estas funções de covariância foram desenvolvidas para anomalias da gravidade Bouguer na região fronteiriça Brasil/Argentina. Estudos com funções polinomiais e de Fourier foram avaliadas utilizando dez por cento dos pontos originais para checagem. Os resultados obtidos em termos de Erro Médio Quadrático (RMS) para a função polinomial de quarta ordem e para a função de Fourier de terceira ordem foram do nível do mGal

A new height datum for Iran based on the combination of gravimetric and geometric geoid models

A new geoid model for Iran (IRG04) was computed based on the least squares modification of the Stokes formula. IRG04 was derived from the most recent gravity anomaly database, SRTM high resolution Digital Elevation Model (DEM) and GRACE GGM02 global geopotential model. In order to define a new height datum for Iran, we attempted to combine this high resolution gravimetric geoid model with GPS/levelling data using the corrective surface approach. The corrective surface was constructed from 224 GPS/levelling points and then evaluated with 35 independent points. Different interpolation techniques were tested for the creation of the corrective surface; among them the Kriging method was selected as it gave the smallest RMS and ‘noise level’ at the comparisons with GPS/levelling data. The RMS fit of the new combined geoid model versus the independent GPS/levelling data is 0.09 m, it is near four times better compared to the original gravimetric geoid model. The combined model should be more convenient and useful in definition of the new height reference surface, specifically in engineering and GPS/levelling projects