952 resultados para 1839 Storm
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Digital image
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Photoinduced diffusion in Se/As2S3 and Sb/As2S3 nanomultilayered thin films are studied by X-ray photoelectron spectroscopy (XPS). The XPS measurements show the atomic movements during photoinduced diffusion in Se/As2S3 and Sb/As2S3 nanomultilayered film. The analysis of experimental data describes the nature of light induced changes indifferent structural units. (C) 2009 Elsevier B.V. All rights reserved.
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Description of the work Shrinking Violets is comprised of two half scale garments in laser cut silk organza, developed with a knotting device to allow for disassembly and reassembly. The first is a jacket in layered red organza including black storm flap details. The second is a vest in jade organza with circles of pink organza attached through a pattern of knots. Research Background This practice-led fashion design research sits within the field of Design for Sustainability (DfS) in fashion that seeks to mitigate the environmental and ethical impacts of fashion consumption and production. The research explores new systems of garment construction for DfS, and examines how these systems may involve ‘designing’ new user interactions with the garments. The garments’ construction system allows them to be disassembled and recycled or reassembled by users to form a new garment. Conventional garment design follows a set process of cutting and construction, with pattern pieces permanently machine-stitched together. Garments typically contain multiple fibre types; for example a jacket may be constructed from a shell of wool/polyester, an acetate lining, fusible interlinings, and plastic buttons. These complex inputs mean that textile recycling is highly labour intensive, first to separate the garment pieces and second to sort the multiple fibre types. This difficulty results in poor quality ‘shoddy’ comprised of many fibre types and unsuitable for new apparel, or in large quantities of recyclable textile waste sent to landfill (Hawley 2011). Design-led approaches that consider the garment’s end of life in the design process are a way of addressing this problem. In Gulich’s (2006) analysis, use of single materials is the most effective way to ensure ease of recycling, with multiple materials that can be detached next in effectiveness. Given the low rate of technological innovation in most apparel manufacturing (Ruiz 2011), a challenge for effective recycling is how to develop new manufacturing methods that allow for garments to be more easily disassembled at end-of-life. Research Contribution This project addresses the research question: How can design for disassembly be considered within the fashion design process? I have employed a practice-led methodology in which my design process leads the research, making use of methods of fashion design practice including garment and construction research, fabric and colour research, textile experimentation, drape, patternmaking, and illustration as well as more recent methods such as laser cutting. Interrogating the traditional approaches to garment construction is necessarily a technical process; however fashion design is as much about the aesthetic and desirability of a garment as it is about the garment’s pragmatics or utility. This requires a balance between the technical demands of designing for disassembly with the aesthetic demands of fashion. This led to the selection of luxurious, semi-transparent fabrics in bold floral colours that could be layered to create multiple visual effects, as well as the experimentation with laser cutting for new forms of finishing and fastening the fabrics together. Shrinking Violets makes two contributions to new knowledge in the area of design for sustainability within fashion. The first is in the technical development of apparel modularity through the system of laser cut holes and knots that also become a patterning device. The second contribution lies in the design of a system for users to engage with the garment through its ability to be easily reconstructed into a new form. Research Significance Shrinking Violets was exhibited at the State Library of Queensland’s Asia Pacific Design Library, 1-5 November 2015, as part of The International Association of Societies of Design Research’s (IASDR) biannual design conference. The work was chosen for display by a panel of experts, based on the criteria of design innovation and contribution to new knowledge in design. References Gulich, B. (2006). Designing textile products that are easy to recycle. In Y. Wang (Ed.), Recycling in Textiles (pp. 25-37). London: Woodhead. Hawley, J. M. (2011). Textile recycling options: exploring what could be. In A. Gwilt & T. Rissanen (Eds.), Shaping Sustainable Fashion: Changing the way we make and use clothes (pp. 143 - 155). London: Earthscan. Ruiz, B. (2014). Global Apparel Manufacturing. Retrieved 10 August 2014, from http://clients1.ibisworld.com/reports/gl/industry/default.aspx?entid=470
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The dissertation deals with remote narrowband measurements of the electromagnetic radiation emitted by lightning flashes. A lightning flash consists of a number of sub-processes. The return stroke, which transfers electrical charge from the thundercloud to to the ground, is electromagnetically an impulsive wideband process; that is, it emits radiation at most frequencies in the electromagnetic spectrum, but its duration is only some tens of microseconds. Before and after the return stroke, multiple sub-processes redistribute electrical charges within the thundercloud. These sub-processes can last for tens to hundreds of milliseconds, many orders of magnitude longer than the return stroke. Each sub-process causes radiation with specific time-domain characteristics, having maxima at different frequencies. Thus, if the radiation is measured at a single narrow frequency band, it is difficult to identify the sub-processes, and some sub-processes can be missed altogether. However, narrowband detectors are simple to design and miniaturize. In particular, near the High Frequency band (High Frequency, 3 MHz to 30 MHz), ordinary shortwave radios can, in principle, be used as detectors. This dissertation utilizes a prototype detector which is essentially a handheld AM radio receiver. Measurements were made in Scandinavia, and several independent data sources were used to identify lightning sub-processes, as well as the distance to each individual flash. It is shown that multiple sub-processes radiate strongly near the HF band. The return stroke usually radiates intensely, but it cannot be reliably identified from the time-domain signal alone. This means that a narrowband measurement is best used to characterize the energy of the radiation integrated over the whole flash, without attempting to identify individual processes. The dissertation analyzes the conditions under which this integrated energy can be used to estimate the distance to the flash. It is shown that flash-by-flash variations are large, but the integrated energy is very sensitive to changes in the distance, dropping as approximately the inverse cube root of the distance. Flashes can, in principle, be detected at distances of more than 100 km, but since the ground conductivity can vary, ranging accuracy drops dramatically at distances larger than 20 km. These limitations mean that individual flashes cannot be ranged accurately using a single narrowband detector, and the useful range is limited to 30 kilometers at the most. Nevertheless, simple statistical corrections are developed, which enable an accurate estimate of the distance to the closest edge of an active storm cell, as well as the approach speed. The results of the dissertation could therefore have practical applications in real-time short-range lightning detection and warning systems.
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Potable water resources are being depleted at an alarming rate worldwide. Storm water is a hugely under-utilized resource that could help as extreme weather events become more frequent...
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Right as an Argument. Leo Mechelin and the Finnish Question 1886-1912 At the turn of the 20th century the Finnish Question rose up as a political and juridical issue at the international arena. The vaguely précised position of Finland in the Russian empire led to diverse conclusions concerning the correctness of the February manifesto of 1899. It was predominantly among a European elite of politicians, cultural workers and academics the issue rose some interest. Finns were active making propaganda for their cause, and they put an emphasis on the claim that the right was on the Finnish side. In the study Elisabeth Stubb compare the Finnish, Russian and European statements about the Finnish Question and analyse their use of right as an argument. The Finnish Question offers at the same time a case study of a national entity which possesses a political sphere of life but is not fully independent, and its possibilities to drive its interests in an international context. Leo Mechelin (1839-1914), the leader of the Finnish propaganda organization abroad, is used as a point of departure. The biographical stance is formed into a triangle, where Leo Mechelin, the idea of right and the Finnish Question abroad are the three cornerstones. The treatment of one cornerstone sheds a ligth on the two others. The metaphor of triangulation also worked as a method to reach "a third stance" in a scinetific and political issue that usually is polarised into two opposite alternatives. An adherence to a strict legal right could not in the end offer a complete, unquestionable and satisfactory solution to the Finnsih Question, it was dependent on "the right of state wisdom and sound insight". The Finnish propaganda abroad used almost completely alternative ways of making politics. The propaganda did not have a decisive effect on countries' official politics, but gained unofficial support, especially in the public opinion and in academic statements. Mechelin claimed that the political field was dependent on public opinion and scientific research. Together with the official politics these two fields formed a triangle that shared the task of balancing the political arena and preventing it from making unwise decisions of taking an unjust turn. The international sphere worked as a balancing part in the Finnish Question. Mechelin tried by claiming the status of state for Finland's part to secure the country a place at the official international arena. At the same time, and especially when the claim was not fully adopted, he emphasised, and in a European context worked for, that right would become the guiding light not only for international relations, but also for the policy making in the inner life of the state.
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This study explores the utility of polarimetric measurements for discriminating between hydrometeor types with the emphasis on (a) hail detection and discrimination of its size, (b) measurement of heavy precipitation, (c) identification and quantification of mixed-phase hydrometeors, and (d) discrimination of ice forms. In particular, we examine the specific differential phase, the backscatter differential phase, the correlation coefficient between vertically and horizontally polarized waves, and the differential reflectivity, collected from a storm at close range. Three range–height cross sections are analyzed together with complementary data from a prototype WSR-88D radar. The case is interesting because it demonstrates the complementary nature of these polarimetric measurands. Self-consistency among them allows qualitative and some quantitative discrimination between hydrometeors.
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In a statistical downscaling model, it is important to remove the bias of General Circulations Model (GCM) outputs resulting from various assumptions about the geophysical processes. One conventional method for correcting such bias is standardisation, which is used prior to statistical downscaling to reduce systematic bias in the mean and variances of GCM predictors relative to the observations or National Centre for Environmental Prediction/ National Centre for Atmospheric Research (NCEP/NCAR) reanalysis data. A major drawback of standardisation is that it may reduce the bias in the mean and variance of the predictor variable but it is much harder to accommodate the bias in large-scale patterns of atmospheric circulation in GCMs (e.g. shifts in the dominant storm track relative to observed data) or unrealistic inter-variable relationships. While predicting hydrologic scenarios, such uncorrected bias should be taken care of; otherwise it will propagate in the computations for subsequent years. A statistical method based on equi-probability transformation is applied in this study after downscaling, to remove the bias from the predicted hydrologic variable relative to the observed hydrologic variable for a baseline period. The model is applied in prediction of monsoon stream flow of Mahanadi River in India, from GCM generated large scale climatological data.
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CuFe2O4 nanograins have been prepared by the chemical co-precipitation technique and calcined in the temperature range of 200-1200 degrees C for 3 h. A wide range of grain sizes has been observed in this sintering temperature range, which has been determined to be 4 to 56 nm. Formation of ferrite has also been confirmed by FTIR measurement through the presence of wide band near 600 and 430 cm(-1) for the samples in the as-dried condition. Systematic variation of wave number has been observed with the variation of the calcination temperature. B-H loops exhibit transition from superparamagnetic to ferrimagnetic state above the calcination temperature of 900 degrees C. Coercivity of the samples at lower calcination temperature of 900 degrees C reduces significantly and tends towards zero coercivity, which is suggestive of superparamagnetic transition for the samples sintered below this temperature. Frequency spectrum of the real and imaginary part of complex initial permeability have been measured for the samples calcined at different temperature, which shows wide range of frequency stability. Curie temperature, T-c has been measured from temperature dependence initial permeability at a fixed frequency of 100 kHz. Although there is small variation of T-c with sintering temperature, the reduction of permeability with temperature drastically reduce for lower sintering temperature, which is in conformity with the change of B-H loops with the variation of sintering temperatures.
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During recent years, an increase in the intensity of pre-monsoon tropical cyclones (TCs) is observed over the Arabian Sea. This study suggests that this increase is due to epochal variability in the intensity of TCs and is associated with epochal variability in the storm-ambient vertical wind shear and tropical cyclone heat potential (TCHP). There is a significant increase (0.53kJcm(-2)year(-1)) of TCHP during recent years. The warmer upper ocean helps TCs to sustain or increase their intensity by an uninterrupted supply of sensible and latent heat fluxes from the ocean surface to the atmosphere.
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The current understanding of wildfire effects on water chemistry is limited by the quantification of the elemental dissolution rates from ash and element release rate from the plant litter, as well as quantification of the specific ash contribution to stream water chemistry. The main objective of the study was to provide such knowledge through combination of experimental modelling, field data and end-member mixing analysis (EMMA) of wildfire impact on a watershed scale. The study concerns watershed effects of fire in the Indian subcontinent, a region that is typically not well represented in the fire science literature. In plant litter ash, major elements are either hosted in readily-soluble phases (K, Mg) such as salts, carbonates and oxides or in less-soluble carrier-phases (Si, Ca) such as amorphous silica, quartz and calcite. Accordingly, elemental release rates, inferred from ash leaching experiments in batch reactor, indicated that the element release into solution followed the order K > Mg > Na > Si > Ca. Experiments on plant litter leaching in mixed-flow reactor indicated two dissolution regimes: rapid, over the week and slower over the month. The mean dissolution rates at steady-state (R-ss) indicated that the release of major elements from plant litter followed the order Ca > Si > Cl > Mg > K > Na. R-ss for Si and Ca for tree leaves and herbaceous species are similar to those reported for boreal and European tree species and are higher than that from the dissolution of soil clay minerals. This identifies tropical plant litters as important source of Si and Ca for tropical surface waters. In the wildfire-impacted year 2004, the EMMA indicated that the streamflow composition (Ca, K, Mg, Na, Si, Cl) was controlled by four main sources: rainwater, throughfall, ash leaching and soil solution. The influence of the ash end-member was maximal early in the rainy season (the two first storm events) and decreased later in the rainy season, when the stream was dominated by the throughfall end-member. The contribution of plant litter decay to the streamwater composition for a year not impacted by wildfire is significant with estimated solute fluxes originating from this decay greatly exceed, for most major elements, the annual elemental dissolved fluxes at the Mule Hole watershed outlet. This highlighted the importance of solute retention and vegetation back uptake processes within the soil profile. Overall, the fire increased the mobility and export of major elements from the soils to the stream. It also shifted the vegetation-related contribution to the elemental fluxes at the watershed outlet from long-term (seasonal) to short-term (daily to monthly). (C) 2014 Elsevier B.V. All rights reserved.
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The objective of this study is to evaluate the ability of a European chemistry transport model, `CHIMERE' driven by the US meteorological model MM5, in simulating aerosol concentrations dust, PM10 and black carbon (BC)] over the Indian region. An evaluation of a meteorological event (dust storm); impact of change in soil-related parameters and meteorological input grid resolution on these aerosol concentrations has been performed. Dust storm simulation over Indo-Gangetic basin indicates ability of the model to capture dust storm events. Measured (AERONET data) and simulated parameters such as aerosol optical depth (AOD) and Angstrom exponent are used to evaluate the performance of the model to capture the dust storm event. A sensitivity study is performed to investigate the impact of change in soil characteristics (thickness of the soil layer in contact with air, volumetric water, and air content of the soil) and meteorological input grid resolution on the aerosol (dust, PM10, BC) distribution. Results show that soil parameters and meteorological input grid resolution have an important impact on spatial distribution of aerosol (dust, PM10, BC) concentrations.
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The 2004 earthquake left several traces of coseismic land deformation and tsunami deposits, both on the islands along the plate boundary and distant shores of the Indian Ocean rim countries. Researchers are now exploring these sites to develop a chronology of past events. Where the coastal regions are also inundated by storm surges, there is an additional challenge to discriminate between the deposits formed by these two processes. Paleo-tsunami research relies largely on finding deposits where preservation potential is high and storm surge origin can be excluded. During the past decade of our work along the Andaman and Nicobar Islands and the east coast of India, we have observed that the 2004 tsunami deposits are best preserved in lagoons, inland streams and also on elevated terraces. Chronological evidence for older events obtained from such sites is better correlated with those from Thailand, Sri Lanka and Indonesia, reiterating their usefulness in tsunami geology studies. (C) 2014 Elsevier Ltd. All rights reserved.
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Storage of water within a river basin is often estimated by analyzing recession flow curves as it cannot be `instantly' estimated with the aid of available technologies. In this study we explicitly deal with the issue of estimation of `drainable' storage, which is equal to the area under the `complete' recession flow curve (i.e. a discharge vs. time curve where discharge continuously decreases till it approaches zero). But a major challenge in this regard is that recession curves are rarely `complete' due to short inter-storm time intervals. Therefore, it is essential to analyze and model recession flows meaningfully. We adopt the wellknown Brutsaert and Nieber analytical method that expresses time derivative of discharge (dQ/dt) as a power law function of Q : -dQ/dt = kQ(alpha). However, the problem with dQ/dt-Q analysis is that it is not suitable for late recession flows. Traditional studies often compute alpha considering early recession flows and assume that its value is constant for the whole recession event. But this approach gives unrealistic results when alpha >= 2, a common case. We address this issue here by using the recently proposed geomorphological recession flow model (GRFM) that exploits the dynamics of active drainage networks. According to the model, alpha is close to 2 for early recession flows and 0 for late recession flows. We then derive a simple expression for drainable storage in terms the power law coefficient k, obtained by considering early recession flows only, and basin area. Using 121 complete recession curves from 27 USGS basins we show that predicted drainable storage matches well with observed drainable storage, indicating that the model can also reliably estimate drainable storage for `incomplete' recession events to address many challenges related to water resources. (C) 2014 Elsevier Ltd. All rights reserved.