988 resultados para Protection means


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In this paper, we propose a system level design approach considering voltage over-scaling (VOS) that achieves error resiliency using unequal error protection of different computation elements, while incurring minor quality degradation. Depending on user specifications and severity of process variations/channel noise, the degree of VOS in each block of the system is adaptively tuned to ensure minimum system power while providing "just-the-right" amount of quality and robustness. This is achieved, by taking into consideration block level interactions and ensuring that under any change of operating conditions, only the "less-crucial" computations, that contribute less to block/system output quality, are affected. The proposed approach applies unequal error protection to various blocks of a system-logic and memory-and spans multiple layers of design hierarchy-algorithm, architecture and circuit. The design methodology when applied to a multimedia subsystem shows large power benefits ( up to 69% improvement in power consumption) at reasonable image quality while tolerating errors introduced due to VOS, process variations, and channel noise.

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The water and sewerage sectors' combined emissions account for just over 1% of total UK emissions, while household water heating accounts for a further 5%. Energy use, particularly electricity, is the largest source of emissions in the sector. Water efficiency measures should therefore result in reduced emissions from a lower demand for water and wastewater treatment and pumping, as well as from decreased domestic water heating. Northern Ireland Water (NI Water) is actively pursuing measures to reduce its carbon footprint. This paper investigated the carbon impacts of implementing a household water efficiency programme in Northern Ireland. Assuming water savings of 59.6 L/prop/day and 15% uptake among households, carbon savings of 0.6% of NI Water's current net operational emissions are achievable from reduced treatment and pumping. Adding the carbon savings from reduced household water heating gives savings equivalent to 6.2% of current net operational emissions. Cost savings to NI Water are estimated as 300,000 per year. The cost of the water efficiency devices is approximately 1.6 million, but may be higher depending on the number of devices distributed relative to the number installed. This paper has shown clear carbon benefits to water efficiency, but further research is needed to examine social and cost impacts. © IWA Publishing 2013.

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A novel numerical technique is proposed to model thermal plasma of microseconds/milliseconds time-scale effect. Modelling thermal plasma due to lightning strike will allow the estimation of electric current density, plasma pressure, and heat flux at the surface of the aircraft structure. These input data can then be used for better estimation of the mechanical/thermal induced damage on the aircraft structures for better protection systems design. Thermal plasma generated during laser cutting, electric (laser) welding and other plasma processing techniques have been the focus of many researchers. Thermal plasma is a gaseous state that consists from a mixture of electrons, ions, and natural particles. Thermal plasma can be assumed to be in local thermodynamic equilibrium, which means the electrons and the heavy species have equal temperature. Different numerical techniques have been developed using a coupled Navier Stokes – Heat transfer – Electromagnetic equations based on the assumption that the thermal plasma is a single laminar gas flow. These previous efforts focused on generating thermal plasma of time-scale in the range of seconds. Lighting strike on aircraft structures generates thermal plasma of time-scale of milliseconds/microseconds, which makes the previous physics used not applicable. The difficulty comes from the Navier-Stokes equations as the fluid is simulated under shock load, this introducing significant changes in the density and temperature of the fluid.

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Using first-principles molecular dynamics simulations, we have investigated the notion that amino acids can play a protective role when DNA is exposed to excess electrons produced by ionizing radiation. In this study we focus on the interaction of glycine with the DNA nucleobase thymine. We studied thymine-glycine dimers and a condensed phase model consisting of one thymine molecule solvated in amorphous glycine. Our results show that the amino acid acts as a protective agent for the nucleobase in two ways. If the excess electron is initially captured by the thymine, then a proton is transferred in a barrier-less way from a neighboring hydrogen-bonded glycine. This stabilizes the excess electron by reducing the net partial charge on the thymine. In the second mechanism the excess electron is captured by a glycine, which acts as a electron scavenger that prevents electron localization in DNA. Both these mechanisms introduce obstacles to further reactions of the excess electron within a DNA strand, e.g. by raising the free energy barrier associated with strand breaks.

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This chapter discusses the use of proportionality in age discrimination cases before the Court of Justice of the European Union. It argues that the Court does not use this concept systematically - indeed it exposes some contradiction that make the case law seem arbitrary - and proposes a more fruitful use of the principle, which is in line with a modern conception of human rights. The chapter argues that the principle of proportionality stems from the time when human rights served the recently liberated burgeois elite in guarding their rights to property and liberty against the state. Today, states not only respect human rights (which is fully sufficient for this elite, who can rely on their inherited wealth to fend for themselves). They also protect and promote human rights, and these activities are a precondition for human rights to be practically relevant for the whole population. This also means that state activity, which is experienced as a limitation of rights to property and liberty by some, may constitute a measure to promote and protect human rights of others. In employment law - the only field where the EU ban on age discrimination is applied - this is a typical situation. If such a situation occurs, the principle of proportionality must be applied in a bifurcated way.It is not sufficient that the limitation of property rights is proportionate for the achievement of a public policy aim. If the aim of public policy is to enable the effective use of human rights, the limitation of the state action must be proportionate to the protection and promotion of those human rights. It is argued that the principle of proportionality is superior to less structures balancing acts (e.g. the Wednesbury principle), if it is applied both ways. Going over to the field of age discrimination, the chapter identifies a number of potentially colliding aims pursued in this field. Banning age discrimination may relate to genuine aims of anti-discrimination law if bias against older or very young workers is addressed. However, the EU ban of discrimination against all ages also serves to restructure employment law and policy to the age of flexibilisation, replacing the synchronisation principle that has been predominant for the welfare states of the 20th century. The former aim is related to human rights protection, while the latter aim is not (at least not always). This has consequences for applying the proportionality test. The chapter proposes different ways to argue the most difficult age discrimination cases, where anti-discrimination rationales and flexibilisation rationales clash

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Child protection social work is acknowledged as a very stressful occupation, with high turnover and poor retention of staff being a major concern. This paper highlights themes that emerged from findings of sixty-five articles that were included as part of a systematic literature review. The review focused on the evaluation of research findings, which considered individual and organisational factors associated with resilience or burnout in child protection social work staff. The results identified a range of individual and organisational themes for staff in child protection social work. Nine themes were identified in total. These are categorised under ‘Individual’ and ‘Organisational’ themes. Themes categorised as individual included personal history of maltreatment, training and preparation for child welfare, coping, secondary traumatic stress, compassion fatigue and compassion satisfaction. Those classified as organisational included workload, social support and supervision, organisational culture and climate, organisational and professional commitment, and job satisfaction or dissatisfaction. The range of factors is discussed with recommendations and areas for future research are highlighted.

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This paper responds to demands for greater academic investigation into environmental protection, specifically the practical and structural problems which underpin regulatory compliance in the planning system. It critiques traditional theories of regulation and answers calls for the development of a thematic lens to facilitate the scrutiny of not only operational practice, but also the broader institutional regime. An empirical investigation builds upon the construct of really responsive regulation to study planning control and it becomes apparent that not only are there significant procedural planning difficulties facing regulatory compliance, but also that a much wider raft of issues must be considered if the complex equation is to be solved. The findings demonstrate how theory can be applied to enrich our rudimentary understanding of deep-seated problems and foster insights into areas of structural importance which are relevant to both planning and the wider regulatory arena.

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We propose a radiation source based on a magnetic mirror cavity. Relativistic electrons are simulated entering the cavity and their trajectories and resulting emission spectra are calculated. The uniformity of the particle orbits is found to result in a frequency comb in terahertz range, the precise energies of which are tunable by varying the electron's gamma-factor. For very high energy particles, radiation friction causes the spectral harmonics to broaden and we suggest this as a possible way to verify competing classical equations of motion.

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Well-defined correlates of protective immunity are an essential component of rational vaccine development. Despite years of basic science and three HIV vaccine efficacy trials, correlates of immunological protection from HIV infection remain undefined. In December 2010, a meeting of scientists engaged in basic and translational work toward developing HIV-1 vaccines was convened. The goal of this meeting was to discuss current opportunities and optimal approaches for defining correlates of protection, both for ongoing and future HIV-1 vaccine candidates; specific efforts were made to engage young scientists. We discuss here the highlights from the meeting regarding the progress made and the way forward for a protective HIV-1 vaccine.

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The use of cathodic protection in reinforced concrete is becoming increasingly common with such systems being installed on a number of structures throughout the United Kingdom and Ireland. However the prescribed design lives (or service life) of each cathodic protection system vary widely. The aim of this project was to assess the effectiveness of a sacrificial anode cathodic protection system and to predict its design life through a series of laboratory based experiments. The experimental plan involved casting a number of slabs which represented a common road bridge structure. The corrosion of the steel within the experimental slabs was then accelerated prior to installation of a cathodic protection system. During the experiment corrosion potential of the steel reinforcement was monitored using half-cell measurement. Additionally the current flow between the cathodic protection system and the steel reinforcement was recorded to assess the degree of protection. A combination of theoretical calculations and experimental results were then collated to determine the design life of this cathodic protection system. It can be concluded that this sacrificial anode based cathodic protection system was effective in halting the corrosion of steel reinforcement in the concrete slabs studied. Both the corrosion current and half-cell potentials indicated a change in passivity for the steel reinforcement once sacrificial anodes were introduced. The corrosion current was observed to be sensitive to the changes to the exposure environment. Based on the experimental variables studied the design life of this sacrificial anode can be taken as 26 to 30 years.

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This paper presents a simple polarization encoding strategy that operates using only single element dual port transmit and receive antennas in such a way that selective spatial scrambling of QPSK data can be effected. The key transmitter and receiver relationships needed for this operation to occur are derived. The system is validated using a cross dipole antenna arrangement. Unlike all previously reported physical layer wireless solutions the approach developed in this paper transfers the security property to the receive side resulting in very simple transmit and receive side architectures thus avoiding the need for near field modulated array technology. In addition the scheme permits, for the first time, multiple spatially separated secured receive sites to operate in parallel.

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It is now 15 years since the signing of the 1998 Belfast (or ‘Good Friday’) Peace Agreement which committed all participants to exclusively democratic and peaceful means of resolving differences, and towards a shared and inclusive society defined by the principles of respect for diversity, equality and the interdependence of people. In particular, it committed participants to the protection and vindication of the human rights of all. This is, therefore, a precipitous time to undertake a probing analysis of educational reforms in Northern Ireland associated with provision in the areas of inclusion and special needs education. Consequently, by drawing upon analytical tools and perspectives derived from critical policy analysis, this article, by Ron Smith from the School of Education, Queen’s University Belfast, discusses the policy cycle associated with the proposed legislation entitled Every School a Good School: the way forward for special educational needs and inclusion. It examines how this policy text structures key concepts such as ‘inclusion’, ‘additional educational needs’ and ‘barriers to learning’, and how the proposals attempt to resolve the dilemma of commonality and difference. Conceived under direct rule from Westminster (April 2006), issued for consultation when devolved powers to a Northern Ireland Assembly had been restored, and with the final proposals yet to be made public, this targeted educational strategy tells a fascinating story of the past, present and likely future of special needs education in Northern Ireland. Before offering an account of this work, it is placed within some broader ecological frameworks.