62 resultados para storm


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A series of laboratory experiments were carried out to investigate the response of a bar-blocked, saltwedge estuary to the imposition of both steady freshwater inflows and transient inflows that simulate storm events in the catchment area or the regular water releases from upstream reservoirs. The trapped salt water forms a wedge within the estuary, which migrates downstream under the influence of the freshwater inflow. The experiments show that the wedge migration occurs in two stages, namely (i) an initial phase characterized by intense shear-induced mixing at the nose of the wedge, followed by (ii) a relatively quiescent phase with significantly reduced mixing in which the wedge migrates more slowly downstream.

Provided that the transition time tT between these two regimes satisfies tT>g′h4L/q3α, as was the case for all our experiments and is likely to be the case for most estuaries, then the transition occurs at time tT=1.2(gα3L6/g′3q2)1/6, where g′=gΔρ/ρ0 is the reduced gravity, g the acceleration due to gravity, Δρ the density excess of the saline water over the density ρ0 of the freshwater, q the river inflow rate per unit width, and L and α are the length and bottom slope of the estuary, respectively.

A simple model, based on conversion of the kinetic energy of the freshwater inflow into potential energy to mix the salt layer, was developed to predict the displacement xw over time t of the saltwedge nose from its initial position. For continuous inflows subject to t<tT, the model predicts the saltwedge displacement as xw/h=1.1 (t/τ)1/3, where the normalizing length and time scales are h=(q2/g)1/3 and τ=g′α2h4L/q3, respectively. For continuous inflows subject to t>tT, the model predicts the displacement as xw/h=0.45N1/6(t/τ)1/6/α, where N=q2/g′h2L is a non-dimensional number for the problem. This model shows very good agreement with the experiments. For repeated, pulsed discharges subject to t<tT, the saltwedge displacement is given by (xw/h)3−(x0/h)(xw/h)2=1.3t/τ, where x0 is the initial displacement following one discharge event but prior to the next event. For pulsed discharges subject to t>tT, the displacement is given by (xw/h)6−(x0/h)(xw/h)5=0.008N(t/τ)/α6. This model shows very good agreement with the experiments for the initial discharge event but does systematically underestimate the wedge position for the subsequent pulses. However, the positional error is less than 15%.

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Australian scientists in Sydney made medical history by creating a life-saving brother for a child with an incurable genetic disease. Features the case of a Tasmanian couple who, with their help, have this life-saving baby, at their third try. The pioneering IVF treatment, which is legal only in N.S.W., hit the news headlines, sparking an ethical storm. Examines the moral and ethical issues that genetic manipulation raises, including the potential uses and misuses of genetic technology. Raises also the spectre of an extreme form of eugenics, as seen in the World War II Nazi push to create a master race through human genetics. Some view eugenics as another form of PGD. Presents the diverse views of eminent ethicists and the Catholic Church, world wide.

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In this sixth and final part of the anthology I will discuss major areas of concern about synchronicity from the perspectives of science, religion, archetypes, causality, meaning, and psi. For convenience, I have spread these major areas across three chapters. In this first chapter I will briefly consider the synchronicity construct from the perspective of its definitions and how it sits epistemologically in the framework of science and the everyday world. I also review the lives of Jung and Pauli, rind discuss their joint effort to integrate science and religion through the principle of synchronicity.

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In this final chapter I will give a synchronistic perspective on psi phenomena,
including telepathy, psi missing, and displacement. I will also consider
the archetype's involement in a self-organizing system that underpins
behaviours which might indicate an unconventional form of psi, likely as
not, suggesting synchronicity, I will conclude with a prospective account of
the possible contributions that snychronocity theory could offer the various
disciplines.

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In six studies on the I Ching - an ancient Chinese system of divination - successful predictions of first- and second-hexagrams (i.e., hexagram hitting) based on pre-selections of corresponding descriptor-pairs have ranged from chance, to significantly above chance. No significant effect below chance has ever been found. Hexagram hitting has been predicted by measures such as paranormal belief, time perspective, and meaningfulness. Storm (2008a) found a near-significant aggregate hexagram hit rate of 27%. Though these results are encouraging, there has been no assessment of the reliability and validity of the main test instrument used in the I Ching studies, the Hexagram Descriptor Form (HDF). To test the validity of the HDF, three control methods were tested against the experimental method. Taking first- and second-hexagram hit rates together, three out of 22 tests on the experimental method (14%) were significant or near-significant. Three significant or near-significant outcomes out of 66 control tests (4.5%) were attributed to chance. Inter-rater reliability was tested using two I Ching experts who judged the 64 descriptor-pairs of the HDF for suitability against their corresponding hexagram readings. The correlation between judges' ratings was not significant (the mean rating ranged between 60% and 82%). Using the pooled data of six studies, the HDF was tested for possible selection and outcome biases. A selection bias was found, but no outcome biases were found. The I Ching and the HDF were considered suitable for parapsychological research.

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Historically, psi effects have been linked to altered states of consciousness (ASCs; Bem and Honorton, 1994). In this context, arguably the most widely used technique is the Ganzfeld. However, in recent times, scholars (e.g., Alvarado, 1998; Braud, 2005; Scimeca, Boca, and Iannuzzo, 2001) have formulated cogent arguments that cast doubt on whether the Ganzfeld is, in fact, an ASC that is psi-conducive. Consequently, it may prove prudent to investigate other conditions that induce ostensible ASCs that are purportedly psi-conducive, and it would be wise to get feedback from test participants in these states. In this theoretical paper, we propose that psi effects may be enhanced (i.e., strengthened) using a shamanic-like treatment. On that basis, we argue that parapsychologists must go beyond the assumption that psi effects are optimised under conditions that are inherently passive procedures, and foster techniques that require cognitive action from test participants.

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This article discusses the added stress that nursing ethics will face in the future because of climate change, peak petroleum production, and solar storm scenarios. These developing problems have the ability to overwhelm and destroy countries and peoples with severe heat waves, frequent catastrophic storms, and vector-born diseases. Such catastrophic events will provide severe tests for nursing ethics and the author recommends that planning must begin for the centuries ahead.

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Bangladesh exemplifies the complex challenges facing densely populated coastal regions. The
pressures on the country are immense: around 145 million people live within an area of just 145,000 sq-km at
the confluence of three major river systems: the Ganges, the Brahmaputra and the Meghna. While progress
has been made, poverty remains widespread, with around 39% of children under five malnourished. Most of
its land-mass lies below 10m above sea level with considerable areas at sea level, leading to frequent and
prolonged flooding during the monsoons. Sea level rise is leading to more flooding as storm surges rise off
higher sea levels, pushing further inland. Higher sea levels also result in salt-water intrusion into freshwater
coastal aquifers and estuaries, contaminating drinking water and farmland. Warmer ocean waters are also
expected to lead to an increase in the intensity of tropical storms.
Bangladesh depends on the South Asian summer monsoon for most of its rainfall which is expected to
increase, leading to more flooding. Climate scientists are also concerned about the stability of monsoon and
the potential for it to undergo a nonlinear phase shift to a drier regime. Bangladesh faces an additional
hydrological challenge in that the Ganges and Brahmaputra rivers both rise in the Himalaya-Tibetan Plateau
region, where glaciers are melting rapidly. The Intergovernmental Panel on Climate Change (IPCC)
concluded that rapid melting is expected to increase river flows until around the late-2030s, by which time
the glaciers are expected to have shrunk from their 1995 extent of 500,000 sq-km to an expected 100,000 sqkm.
After the 2030s, river flows could drop dramatically, turning the great glacier-fed rivers of Asia into
seasonal monsoon-fed rivers. The IPCC concluded that as a result, water shortages in Asia could affect more
than a billion people by the 2050s. Over the same period, crop yields are expected to decline by up to 30% in
South Asia due to a combination of drought and crop heat stress. Bangladesh is therefore likely to face
substantial challenges in the coming decades.
In order to adequately understand the complex, dynamic, spatial and nonlinear challenges facing Bangladesh,
an integrated model of the system is required. An agent-based model (ABM) permits the dynamic
interactions of the economic, social, political, geographic, environmental and epidemiological dimensions of
climate change impacts and adaptation policies to be integrated via a modular approach. Integrating these
dimensions, including nonlinear threshold events such as mass migrations, or the outbreak of conflicts or
epidemics, is possible to a far greater degree with an ABM than with most other approaches.
We are developing a prototype ABM, implemented in Netlogo, to examine the dynamic impacts on poverty,
migration, mortality and conflict from climate change in Bangladesh from 2001 to 2100. The model employs
GIS and sub-district level census and economic data and a coarse-graining methodology to allow model
statistics to be generated on a national scale from local dynamic interactions. This approach allows a more
realistic treatment of distributed spatial events and heterogeneity across the country. The aim is not to
generate precise predictions of Bangladesh’s evolution, but to develop a framework that can be used for
integrated scenario exploration. This paper represents an initial report on progress on this project. So far the
prototype model has demonstrated the desirability and feasibility of integrating the different dimensions of
the complex adaptive system and, once completed, is intended to be used as the basis for a more detailed
policy-oriented model.

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Data broadcasting in a mobile ad-hoc network (MANET) is the main method of information dissemination in many applications, in particular for sending critical information to all hosts. Finding an optimal broadcast tree in such networks is a challenging task due to the broadcast storm problem. The aim of this work is to propose a new genetic model using a fitness function with the primary goal of finding an optimal broadcast tree. Our new method, called Genetic Optimisation Model (GOM) alleviates the broadcast storm problem to a great extent as the experimental simulations result in efficient broadcast tree with minimal flood and minimal hops. The result of this model also shows that it has the ability to give different optimal solutions according to the nature of the network.

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Optimizing broadcasting process in mobile ad hoc network (MANET) is considered as a main challenge due to many problems, such as Broadcast Storm problem and high complexity in finding the optimal tree resulting in an NP-hard problem. Straight forward techniques like simple flooding give rise to Broadcast Storm problem with a high probability. In this work, genetic algorithm (GA) that searches over a population that represents a distinguishable ‘structure’ is adopted innovatively to suit MANETs. The novelty of the GA technique adopted here to provide the means to tackle this MANET problem lies mainly on the proposed method of searching for a structure of a suitable spanning tree that can be optimized, in order to meet the performance indices related to the broadcasting problem. In other words, the proposed genetic model (GM) evolves with the structure of random trees (individuals) ‘genetically’ generated using rules that are devised specifically to capture MANET behaviour in order to arrive at a minimal spanning tree that satisfies certain fitness function. Also, the model has the ability to give different solutions depending on the main factors specified such as, ‘time’ (or speed) in certain situations and ‘reachability’ in certain others.

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E-readers, or devices designed primarily for reading e-books, are taking the world by storm. Several papers in library studies and education have examined e-book consumption for academic reading. However, no previous marketing study has investigated consumers’ adoption of e-readers for pleasure reading. We address this gap by testing an extended version of the Technology Acceptance Model (TAM) with emotional attachment (TAME) in this context. Consumers’ attachment to paper books is proposed as a barrier to their adoption of e-readers. This speaks to a key deficiency of the TAM, being its focus on cognition at the expense of consumer emotion. A three-phase study finds support for the TAME, with 64% of the variance explained in consumers’ intentions to adopt e-readers. Emotional attachment to paper books is found to be weakly and negatively associated with consumers’ attitude toward using e-readers. The qualitative findings suggest that e-reader adoption may not involve a binary choice between paper and e-formats.

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Water reuse has become an integral element of the "total water resources planning and management" along with the other elements such as water conservation, water use efficiency and management of the allocation of existing water sources. Researchers are working actively on the following aspects of water reuse: identification and characterization of different wastewaters that could be reclaimed, development of treatment technologies and effluent standards, quantification of potential gains due to recycling and risk management. The wastewaters that can be reclaimed are domestic and industrial wastewaters, grey water, black water, stormwater and rain water and their potential reuse lies in agriculture, aquaculture, industries, non-potable use in residential and community fronts and indirect and direct potable use. The treatment of wastewater ranges from secondary treatment to advanced treatment, which produces different "Classes" of reclaimed water. This paper evaluates the current status of the research on the above-mentioned important aspects of water reuse with relevant case studies and the future demand for reuse water. The direction in which the future-reuse schemes should be formulated so that they are safe, environmentally sustainable and cost effective are also discussed.

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Constructed wetlands provide several benefits that are not solely limited to storm water management and are becoming common in storm water management. In this research, four recently constructed wetlands underwent in situ and laboratory water sampling to determine their efficiency in removing storm water pollutants over a 5-month period. From the sampling results, it was determined that each of the wetlands was able to reduce the concentration of pollutants in the stormwater. To aid in the assessment of the wetlands against each other, a model was developed to determine the extent of removal of stormwater pollutants over the length of the wetland. The results from this model complimented the data collected from the field. Improvements, such as increased amounts of vegetation were recommended for the wetlands with the aim of increasing the effectiveness. Further investigations into the wetlands will allow for better understanding of the wetland's performance.

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Contemporary dance has only recently gained the capability of mapping imagery into 3D theatre environments that appear to move towards and away from the audiences. This capability radically expands the metaphoric content possible in dance work. This work was animated by Megan Beckwith, performed and choreographed by Stephanie Hutchison with the sound designed by Jacques Soddell. The performance combines contemporary dance with stereoscopic illusions and video imagery. The work is based on the Walter Benjamin’s Ninth Thesis on the Philosophy of History, 1938. Benjamin describes the angel of history being ‘caught in a storm’ from Paradise and being ‘propelled into the future to which his back is turned’. This performance comments on how we invariably move into the future by taking our past with us.