Reconfigurable Flood Wall Inspired by Architected Origami

Recent interest in the art of origami has opened a wide range of engineering applications and possibilities. Shape changing structures based on origami have had a large influence on the drive for efficient, sustainable engineering solutions. However, development in novel macro-scale utilization is lacking compared to the effort towards micro-scale devices. There exists an opening for environmentally actuated structures that improve quality for life of humans and the natural environment. Specifically, resilient infrastructure systems could potentially benefit from the tailorable properties and programmable reconfiguration of origami-inspired designs. The realm of flood protection and overall water resources management creates a unique opportunity for adaptable structures. A flood protection system, or flood wall, is one application of the origami technique. In many situations, flood protection is visually displeasing and hinders an otherwise scenic natural environment within a cityscape. By applying a permanent, adaptable protection system in flood-prone areas, not only will general aesthetics be conserved, but quick deployment in disaster situations will be ensured. With a rapidly changing climate and an increase in storm disaster events, an efficient flood-protection system is vital. In this study, simple rigid flood barriers are compared to adaptable wall systems that utilize multi-stable configurations. The flood event is characterized by a surcharge of water that is suddenly introduced–like that of a flash flood–and sustained at steady-state. Small-scale prototypes are tested in a hydraulic flume and compared to a numerical simulation for validation.Ohio State University College of Engineering Undergraduate Research ScholarshipNo embargoAcademic Major: Civil Engineerin

Building and Contesting post-war Housing in Dakar

After the Second World War, European welfare planning was transposed to the African colonies. With regard to housing this meant a true turning point in urban policy. For the first time the colonial state massively invested in the housing of the African urban dwellers. However, the segregationist underground and elite‐focus of the housing schemes at the same time reinforced fundamental inequities in the African city, thereby furthering colonial goals. The promotion of African emancipation was thus accompanied by a strong ‘social engineering’. Yet, Africans were no passive victims of development schemes. In this paper we will take a close look at the housing schemes of the Société Immobilière du Cap Vert (SICAP) in Dakar (Senegal) between 1951 and 1960 (independence). Notwithstanding the significant housing shortages in Dakar, archival records show that a substantial amount of the SICAP houses remained vacant after completion. Apart from too high rents, the main reason was that the SICAP-houses seemed to be designed with the average West-European middle-class family in mind. As a consequence, most houses proved too small and little adjusted to the extended African family, which is well reflected in the many alterations the SICAP houses underwent right from their completion until today. Moreover, the SICAP housing schemes, and in particular their segregationist and elitist underground, caused strong African opposition. Many Africans opposed to the more than 80.000 forced evictions, known in the colonial jargon as ‘déguerpissements’, that were caused by the implementation of the schemes. The result was a fierce battle over land between the government and the inhabitants of Dakar. In particular the Lebou-population demanded adequate compensation for its land in case of expropriation, even if they did not possess any official land title, with equal rewards for Africans and Europeans. Due various forms of active and passive protest of the inhabitants the implementation of the SICAP housing schemes regularly came to a standstill and the government often found itself in ‘a complete impasse’. The study of these different forms of agency and resistance in Dakar is important as it shows that, although colonial rule was strict and compelling, it was possible to escape from it to some degree

Imagined disease and racial segregation: multiple dreams of open space in Kinshasa and Dar es Salaam

It is strange to encounter an open space in the middle of Tanzania’s congested capital, Dar es Salaam. Similarly, one might wonder why there exists a golf course and a zoo besieged by traffic jams in the bustling city centre of Kinshasa, capital of the Democratic Republic of the Congo. The key to understanding the intriguing anomalies in the urban geographies of these capital cities lies in tracing back their histories. After the First World War colonial governments in British Dar es Salaam (1924) and Belgian Kinshasa (1931) dreamed of implementing a physical separation between Africans and Europeans. Although the British indirect rule/association, in fact provided an excellent basis to legitimate racial segregation, the British in Dar es Salaam just like the Belgians in Kinshasa, who applied a policy that was greatly inspired by both British and French rule, but was nonetheless overtly racial, felt forced to legitimate racial segregation with a sanitary discourse. In both colonies similar explanations underpinned the sanitary discourse, such as the statement that a physical distance would prevent malaria mosquitos flying over from the African quarter to the European quarter, or that it would prevent the contamination by germ-ridden rats ‘as these are less likely to move from area to area over an open space’ – all explanations which were far from scientifically proven, and were even broadly contested by empirical observations. This shared use of a sanitation discourse thus shows the controversial character of the planned intervention, but also suggests a certain transnational exchange with regard to the implementation of racial segregation in sub-Saharan Africa. Indeed, a remarkable similarity exists in the place-naming of the separation zones between Africans and Europeans in both capitals: the ‘Neutral Zone’ in British Dar es Salaam and the French equivalent ‘Zone Neutre’ in Belgian Kinshasa. With regard to the ‘neutral zones’ several archival records highlight both in Dar es Salaam and Kinshasa the powerful influence of British and South African sanitation experts (in South Africa already in the beginning of the 20th century a sanitary discourse was used as a pretext and legitimation of racial segregation, a phenomenon that has been called a ‘Sanitation Syndrome’ by Maynard W. Swanson), as well as a significant transnational dialogue between the colonial powers. Through influential manuals, international and above all inter-continental conferences such as the Conference of Principal Medical Officers and Senior Sanitary Officers in Lagos in 1912, the Inter-Colonial Conference on Yellow Fever in Dakar in 1928 and the Sanitary Conference of Chief Health Officers in Cape Town in 1932, these ‘all-purpose experts’ turned racial segregation, and in particular the implementation of ‘neutral zones’ in the urban fabric, into a legitimate sanitary measure, with considerable impact on town planning. Moreover, under the influence of the discipline of Tropical Medicine racial segregation also evolved from a temporary solution in the battle against infectious diseases, to a permanent prevention measure. Therefore, even though epidemics are foremost medical phenomena, in the colonial context they clearly also functioned as political constructions and ideological instruments. This was clearly the case in Dar es Salaam and Kinshasa where imagined diseases formed the basis for racial segregation, as both cities, in contrast to for instance Dakar in 1914, never even faced an outbreak of infectious disease. Although the ‘neutral zones’ became only partly implemented, today they form one of the rare open spaces in the congested city centres of Dar es Salaam and Kinshasa. Only now they seem to fulfil their legitimising sanitation objectives by operating as a lung for the congested city. However, the ‘neutral zones’ still mark a segregation in the urban fabric (albeit more socio-economic than racial nowadays) and are highly inaccessible to most citizens. Moreover, today these rare open spaces stand under high real estate pressures to develop the sites for high-standard commercial and housing purposes. Considering the enormous lack of open space in city centres of Dar es Salaam and Kinshasa, as well as the segregation these open spaces still embody, many more valuable projects could be imagined to turn these open spaces both into sites of encounter and healthy environments accessible to all urban dwellers

The Effect of Fiscal Transparency on Output, Inflation, and Government Debt

This theoretical paper studies the issue of fiscal transparency, which we define as asymmetry of information between the households’ perception of fiscal policy and the actual government balance sheet, in the context of a 24-hour news cycle. We model the economy using the New Keynesian three-equation model to study the effect of fiscal transparency on output, inflation, and especially government debt in order to draw conclusions that are relevant in the realm of policy-making in a sovereign debt crisis scenario. We find that a higher degree of fiscal transparency leads to greater levels of output and inflation as well as higher government debt

The peri-urban fringe of Kinshasa as an in-between space

All over the world, but especially in the Global South, cities expand at a high pace with as a result an ever moving urban frontier and ever growing peri-urban zones. These dispersed peri-urban zones, only in part clustered around one or more historical cores, seem to have a life of their own. While being an integral part of the urbanization process, they cannot be understood in traditional urban terms, they seem to exist in-between the rural and urban, the dense and non-dense, the horizontal and vertical. The illegibility of these sprawling peri-urban landscapes is often related to the failure to read the (production) of these urban landscapes. However, it seems important to understand the peri-urban condition as in many cities in the Global South, for instance Kinshasa (the capital of the DRCongo), the majority of the people live in these kind of settlement patterns and not in the historical core, which is often limited to the former European town. In cities as Kinshasa, the old geographical distinctions between centre and periphery or town and countryside seem to have collapsed, if they ever existed, with the historic/colonial centre becoming gradually peripheric to the periphery. New hierarchies are at play, while old ones are not swept away completely, altogether forming a layered palimpseste (Corboz, 2001). In this paper we will take a dive in Kinshasa’s peri-urban palimpseste in order to understand the underlying mechanisms and dynamics of its spatial production in the post-independence years. While several planning schemes have been drawn in the framework of a French cooperation programme to steer the peri-urban urban development of Kinshasa after independence, none of them has been implemented. In the absence of any urban planning from above, the urbanization process of the city has been primarily directed by the massive appropriation of space by the urban dwellers. This paper aims at highlighting the underlying parallel system of land tenure that guided the urbanization of Kinshasa’s peri-urban fringe

Questions to Luce Irigaray

This article traces the "dialogue" between the work of the philosophers Luce Irigaray and Emmanuel Levinas. It attempts to construct a more nuanced discussion than has been given to date of Irigaray's critique of Levinas, particularly as formulated in 'Questions to Emmanuel Levinas' (Irigaray 1991). It suggests that the concepts of the feminine and of voluptuosity articulated by Levinas have more to contribute to Irigaray's project of an ethics of sexual difference than she herself sometimes appears to think