Zijn we te laat? Deze vraag drong zich op aan journalist en schrijver Frank von Hebel tijdens zijn reis naar Spitsbergen. Hij nam deel aan de SEES-expeditie (Scientific Expedition Edgeøya Svalbard) op het expeditieschip Ortelius. Onder leiding van het Arctisch Centrum van de Rijksuniversiteit Groningen onderzochten vijftig wetenschappers de gevolgen van klimaatverandering voor de wereld van gletsjers, toendra’s en ijsberen.Spitsbergen is het snelst opwarmende gebied ter wereld. Het kwik stijgt er elke tien jaar gemiddeld met een graad Celcius. Von Hebel zag met eigen ogen hoe de beschaving zich meer en meer opdringt aan het ooit ongerepte landschap dat in 1596 werd ontdekt door Willem Barentsz. De gletsjers trekken zich met schrikbarende snelheid terug, de permafrost slinkt zienderogen en jaarlijks haalt men 20.000 kilo afval van de stranden. Zelfs de Wereldzadenbank kwam door smeltwater even blank te staan. Maar ook onze eigen geschiedenis dreigt door de opwarming van de aarde letterlijk en figuurlijk weg te spoelen. Expeditie Spitsbergen neemt de lezer mee in de bijzondere wereld van deze archipel en maakt duidelijk dat klimaatverandering een veelkoppig monster zal zijn.
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From the article: "The term Internet of Things (IoT) is used for situations where one or more devices are connected to a network or possibly the Internet. Most studies focus on the possibilities that arise when a device is capable to share its data with other devices or humans. In this study, the focus is on the device itself and what kind of possibilities an Internet connection gives to the device and its owner or user. Also the data the device needs to participate in a smart way in the IoT are part of this study. Agent technology is the enabling technology for the ideas introduced here. A proof of concept is given, where some concepts proposed in the paper are put into practice."
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Renewable energy sources have an intermittent character that does not necessarily match energy demand. Such imbalances tend to increase system cost as they require mitigation measures and this is undesirable when available resources should be focused on increasing renewable energy supply. Matching supply and demand should therefore be inherent to early stages of system design, to avoid mismatch costs to the greatest extent possible and we need guidelines for that. This paper delivers such guidelines by exploring design of hybrid wind and solar energy and unusual large solar installation angles. The hybrid wind and solar energy supply and energy demand is studied with an analytical analysis of average monthly energy yields in The Netherlands, Spain and Britain, capacity factor statistics and a dynamic energy supply simulation. The analytical focus in this paper differs from that found in literature, where analyses entirely rely on simulations. Additionally, the seasonal energy yield profile of solar energy at large installation angles is studied with the web application PVGIS and an hourly simulation of the energy yield, based on the Perez model. In Europe, the energy yield of solar PV peaks during the summer months and the energy yield of wind turbines is highest during the winter months. As a consequence, three basic hybrid supply profiles, based on three different mix ratios of wind to solar PV, can be differentiated: a heating profile with high monthly energy yield during the winter months, a flat or baseload profile and a cooling profile with high monthly energy yield during the summer months. It is shown that the baseload profile in The Netherlands is achieved at a ratio of wind to solar energy yield and power of respectively Ew/Es = 1.7 and Pw/Ps = 0.6. The baseload ratio for Spain and Britain is comparable because of similar seasonal weather patterns, so that this baseload ratio is likely comparable for other European countries too. In addition to the seasonal benefits, the hybrid mix is also ideal for the short-term as wind and solar PV adds up to a total that has fewer energy supply flaws and peaks than with each energy source individually and it is shown that they are seldom (3%) both at rated power. This allows them to share one cable, allowing “cable pooling”, with curtailment to -for example-manage cable capacity. A dynamic simulation with the baseload mix supply and a flat demand reveals that a 100% and 75% yearly energy match cause a curtailment loss of respectively 6% and 1%. Curtailment losses of the baseload mix are thereby shown to be small. Tuning of the energy supply of solar panels separately is also possible. Compared to standard 40◦ slope in The Netherlands, facade panels have smaller yield during the summer months, but almost equal yield during the rest of the year, so that the total yield adds up to 72% of standard 40◦ slope panels. Additionally, an hourly energy yield simulation reveals that: façade (90◦) and 60◦ slope panels with an inverter rated at respectively 50% and 65% Wp, produce 95% of the maximum energy yield at that slope. The flatter seasonal yield profile of “large slope panels” together with decreased peak power fits Dutch demand and grid capacity more effectively.
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African citizens are increasingly being surveilled, profiled, and targeted online in ways that violate their rights. African governments frequently use pandemic or terrorism-related security risks to grant themselves additional surveillance rights and significantly increase their collection of monitoring apparatus and technologies while spending billions of dollars to conduct surveillance (Roberts et al. 2023). Surveillance is a prominent strategy African governments use to limit civic space (Roberts and Mohamed Ali 2021). Digital technologies are not the root of surveillance in Africa because surveillance practices predate the digital age (Munoriyarwa and Mare 2023). Surveillance practices were first used by colonial governments, continued by post-colonial governments, and are currently being digitalized and accelerated by African countries. Throughout history, surveillance has been passed down from colonizers to liberators, and some African leaders have now automated it (Roberts et al. 2023). Many studies have been conducted on illegal state surveillance in the United States, China, and Europe (Feldstein 2019; Feldstein 2021). Less is known about the supply of surveillance technologies to Africa. With a population of almost 1.5 billion people, Africa is a continent where many citizens face surveillance with malicious intent. As mentioned in previous chapters, documenting the dimensions and drivers of digital surveillance in Africa is
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