1,363 research outputs found

    'I cover myself in the blood of Jesus': Born Again heritage making in Sierra Leone

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    This article concerns the risky terrain of heritage management in Sierra Leone and its navigation by devout Born Again Pentecostal Christians. It engages with the ever-expanding Born Again movement and its narrative of rupture, on the one hand, and the increasingly visible heritage sector and its focus on cultural continuity, on the other. These positions appear irreconcilable: one experiences the past as a dangerous satanic realm, the other as a valuable resource. However, as this article explores, they frequently meet in the workplace as many heritage professionals are also Born Again believers. I am interested in this meeting-point as demonic channels and godly practices converge. I argue that Freetown’s Born Again heritage professionals do not succeed in their roles despite their religion, but because of it

    Imagining Future Agricultural Landscapes in a new Sudan: entitled expertise, cultural intransience and fine warm rain in the English wilds

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    This article sits in response to work on the rolling out of development-centred technical and scientific expertise at the decline of the British empire in Africa. Specifically, it focuses on the imagining of future agricultural landscapes in Sudan, exploring how such imagining was framed by the social and colonial worlds in which scientific knowledge about agricultural capacity in the north and south was produced. It draws on a private archive of letters, photographs and objects compiled by Roger Brain, an agricultural scientist engaged in research and census work for the University of Khartoum in Sudan between 1953 and 1959. His archive reveals the underlying assumptions, conventions and anxieties that framed the ways in which he viewed and understood the landscapes in which he worked. I argue that this framing shaped regionalised notions of inevitable technological transformation in the north, and notions of a fragile cultural distinctiveness coupled with a deep nostalgia for rural intransience in the south. Ultimately I suggest that this shaped the production of scientific knowledge by Roger Brain and others like him, woven through the production of policy and planning regarding Sudan’s economic future after independence

    V-Band Fully Metallic Geodesic Luneburg Lens Antenna

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    Antennas in emerging millimeter-wave (mm-wave) appli- cations are often required to have low losses and produce a steerable directive beam. These properties are achievable with fully metallic geodesic Luneburg lens antennas. In this communication, we report the first experimental verification of a geodesic Luneburg lens antenna in the V-band. The designed lens antenna is fed with 13 waveguides providing beam switching capability in a 110◦ range. The lens is implemented in the parallel plate waveguide (PPW) technology. The antenna is manufactured in two pieces, and a tolerance analysis indicates that gaps between the pieces can cause a severe performance degradation. Based on this tolerance analysis, two measures are taken to alleviate the manufacturing tolerances for the prototype. First, electromagnetic band gap (EGB) structures are placed around the feeding waveguides. Second, the electrical contact between the two pieces is improved in critical regions. Two prototypes are manufactured, one without and one with the extra measures implemented. The measured radiation patterns of the prototype without these measures have high side lobes and low realized gain compared with the simulation. The measurements of the robust version of the prototype agree well with the simulations and demonstrate the applicability of geodesic Luneburg lens antennas for applications in the V-band.Strategic Innovation Program Smarter Electronics System under Project High-Int 2019-02103European Space Agency European Commission 4000125905/18/NLVR Project 2019-0393

    Virtual Reality-modeller i planlegging

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    Dagens og morgendagens prosjekter blir stadig mer komplekse i form av stadig strengere og mer optimale krav innen trafikkavvikling, okonomi, estetikk, drift og vedlikehold, sikkerhet osv. Onsket om bedre og mer realistisk forhandssimulering og pavirkning av hele eller deler av prosjektet i tidligst mulig planfase gjor at ny teknologi hele tiden hjelper ingenioren til raskere, billigere og bedre planlegging, mens det rent faglige fokus kanskje er kommet noe i bakgrunnen. Derfor ma det kunne sies at transparantpapiret (matpapiret) sansynligvis har gjort mere for den rent faglige utviklingen av selve prosjektene enn EDB hittill.Virtual Reality (kunnstig virkeligehet) kan her bety et lite kvantesprang innen teknisk hjelp under planlegging og prosjektering og kanskje komme pa hoyde med matpapirets betydning nar det gjelder a skaffe ingnioren et mer intuitivt og faglig grensesprengende hjelpemiddel. Virtual Reality aktualiseres i dag gjennom rimelige biblioteker som er tilgjengelig under Windows pa allminnelige PC’er.I Norge er det startet et forskningsprosjekt med formal og testimplementere VR i det utbredte og CAD-baserte prosjekteringssystemet NovaCAD. Arbeidet har pagatt 1 ar og har som formal og tilby komplett og realistisk 3D i tidlig planfase pa en enkel mate for planleggeren. Med VR menes ogsa at man kan bevege seg trinnlost og direkte i et kunstig rom vha. spesielt pereferiutstyr som VR-hjelm, briller, hanske, ratt osv

    Encounters of culture, heritage and development: exploring global connection in Sierra Leone

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    This thesis examines the relationships emerging between culture, heritage and development in Sierra Leone. The concept of ‘culture for development’ is increasingly influential as a framework for intervention in both development and heritage work. However, it has so far received limited critical attention. Using a multi-­‐sited ethnographic approach, this research traces the complexities and contradictions that transpire as Sierra Leone’s cultural sector attempts to establish its position within the country’s future. ‘Culture for development’ emerges from a recognition that intervention has historically failed to respond to local contexts. This thesis proposes that in Sierra Leone, such an agenda is obscured by wider political, professional and personal concerns over the role of the past within a context of aspirational change and transformation

    Low-Dispersive Leaky-Wave Antennas for mmWave Point-to-Point High-Throughput Communications

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    Degradation and Uptake of Benzene in Laboratory Phytoremediation Studies

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    In Whole-Plant Laboratory Studies, Hybrid Poplar Trees Were Shown to Impact a Variety of Fate and Transport Mechanisms for Benzene. Laboratory Experiments Investigated the Distribution of the Contaminant in the Plant Tissues, Degradation in the Soil Profile, and Volatilization from Both the Soil and Leaf Tissues. a New Testing System Was Developed that Allowed for Rapid Testing that is More Field-Representative Than Earlier Studies. Whole Plants Were Utilized in a Reactor Design that Included Both a Saturated and a Vadose Zone. the Continuous Feed Reactors Were Supplied with a Steady Influent Benzene Stream to Mimic Plume Conditions. the Presence of the Poplar Trees Enhanced the Degradation Rate of the Benzene, and Dramatically Decreased the Effluent Mass of Benzene. Benzene Was Also Volatilized from the Leaf Tissues, Providing Evidence to the Extent of Plant Enhanced Volatilization that Has Not Been Previously Documented. the Observed Degradation and Removal Pathways Were a Result of Active/live Trees. Reactors with Killed Controls Did Not Exhibit the Removal Seen in the Live Tree Replicates. the Soil Profile Maintained Higher Degradation Rates with the Trees Present. Causes for the Higher Degradation Rates Appeared to Be Larger Microbial Populations of Benzene Degraders and Preferable Redox Conditions in the Presence of the Poplars. These Results Combined with Previous Hydroponic and Related Field Scale Studies to Provide Evidence that Phytoremediation Has Potential for Effective, Efficient, and Environmentally Friendly Application at Benzene Contaminated Sites, and Potentially Other Contaminated Sites with Biodegradable Organics or VOCs

    Complicating Culture for Development: Negotiating ‘Dysfunctional Heritage’ in Sierra Leone

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    At least since the publication of Our Creative Diversity , the report of the UN World Commission on Culture and Development, in 1996, discourses concerning ‘the power of culture for development’ have formed part of that circulating concatenation of ideas, terms and images that characterizes what we might regard as the ‘ideoscape’ of international development (cf. Appadurai 1990: 9-10). Alongside such buzzwords as participation , empowerment and poverty reduction (Cornwall and Brock 2005), there has been a programmatic diffusion of ideas that link the realms of culture and development. Thus, culture is said to be ‘a fundamental component of sustainable development’, ‘a powerful global economic engine’, ‘a vehicle for social cohesion and stability’, and ‘a repository of knowledge, meanings and values that permeate all aspects of our lives’ (UNESCO 2010: 2-6)

    Dispersion Analysis of Periodically Loaded Transmission Lines with Twist Symmetry Using the Mode-Matching Technique

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    A mode-matching formulation is presented and used to analyze the dispersion properties of twist-symmetric transmission lines. The structures are coaxial lines periodically loaded with infinitely thin screens, which are rotated with respect to each other to possess twist symmetry. The results obtained using the proposed formulation are in good agreement with those of commercial simulators. Furthermore, using the presented mode-matching formulation, it is demonstrated that the propagation characteristics in the twist-symmetric structures are linked to the scattering and coupling of the higher order modes. The physical insight offered by this analysis is valuable for the design of various electromagnetic devices, such as filters, antennas, and phase-shifters.Ministerio de Ciencia, Innovación y Universidades PRX19/00025Ministerio de Economía y Competitividad TEC2017-84724-

    Benzene Toxicity and Removal in Laboratory Phytoremediation Studies

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    Hybrid Poplar Cuttings Were Shown to Impact the Fate and Transport of Subsurface Benzene, While Toxicity to the Poplars Was Not Observed. Laboratory Experiments Investigated the Toxicity Response of Poplar Cuttings to Benzene Exposure, Contaminant Distribution in Plant Tissues, Contaminant Degradation in the Soil Profile, and Contaminant Volatilization from the Soil and Plant Tissues. Two Separate Studies Were Conducted to Evaluate These Parameters. the First Study Examined the Toxicity of Benzene to Hybrid Poplar Cuttings in Batch Reactors. Poplar Cuttings Were Exposed to Various Concentrations of Benzene Contaminated Water in Two Different Types of Soil. Transpiration Rates Were Measured as an Indicator of Acute Toxicity. No Acute Toxicity Was Noted for Dose Concentrations Up to 1,000 Ppm. the Second Study Evaluated Benzene Fate and Transport. Live Poplar Cuttings and Excised Controls Were Planted in Flow-Through Reactors and Supplied with an Influent Benzene Stream to Mimic Plume Conditions. the Presence of Live Poplar Cuttings Enhanced Benzene Degradation and Decreased the Effluent Mass of Benzene. a Small Amount of Benzene Was Also Volatilized from the Plant Tissues, Providing Evidence of Plant-Enhanced Volatilization. Causes for the Higher Degradation Rates Appeared to Be Greater Microbial Populations of Benzene Degraders and a More Oxygenrich Environment. the Higher Redox Potential Observed May Be an Artifact of the Laboratory Reactor Design. the Results Obtained in This Research Combined with Previous Studies Provide Evidence that Phytoremediation Has the Potential for Effective, Efficient, and Environmentally Friendly Application at Sites Highly Contaminated with Benzene and Potentially for Other Sites Contaminated with Biodegradable Organics or Volatile Organic Compounds
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