Efficient use of energy

World energy demand is projected to grow by more than 50% by 2030.[21] Improving energy efficiency is one of the most economical and short to medium term ways Scotland can reduce its dependence on fossil fuels and reduce its emissions of greenhouse gases. Transportation and buildings, which account for two thirds of energy usage [16], consume far more than they need to, but even though there are many affordable energy efficient technologies that can save consumers money, current utilisation is small. To overcome this, the government must adopt policies that invest in research and development programs that target energy efficiency. Incentives schemes if properly implemented can stimulate and encourage energy efficiency which is one of Scotland's great hidden energy opportunities. This paper outlines the position of the Institution of Engineers and Shipbuilders in Scotland and makes recommendations for the Scottish Government by two separate means of improving energy efficiency; reducing wastage and providing the same end need using less energy

Contribution to Efficient Use of Narrowband Radio Channel

Předkládaná práce se soustředí na problematiku využívání úzkopásmového rádiového kanálu rádiovými modemy, které jsou určené pro průmyslové aplikace pozemní pohyblivé rádiové služby, specifikované v dominantní míře Evropským standardem ETSI EN 300 113. Tato rádiová zařízení se používají v kmitočtových pásmech od 30 MHz do 1 GHz s nejčastěji přidělovanou šířkou pásma 25 kHz a ve většině svých instalací jsou využívána ve fixních nebo mobilních bezdrátových sítích. Mezi typické oblasti použití patří zejména datová telemetrie, aplikace typu SCADA, nebo monitorování transportu strategických surovin. Za hlavní znaky popisovaného systému lze označit komunikační pokrytí značných vzdáleností, dané především vysokou výkonovou účinnosti datového přenosu a využívaní efektivních přístupových technik na rádiový kanál se semiduplexním komunikačním režimem. Striktní požadavky na elektromagnetickou kompatibilitu umožňují těmto zařízením využívat spektrum i v oblastech kmitočtově blízkým jiným komunikačním systémům bez nutnosti vkládání dodatečných ochranných frekvenčních pásem. Úzkopásmové rádiové komunikační systémy, v současnosti používají převážně exponenciální digitální modulace s konstantní modulační obálkou zejména z důvodů velice striktních omezení pro velikost výkonu vyzářeného do sousedního kanálu. Dosahují tak pouze kompromisních hodnot komunikační účinnosti. Úpravy limitů příslušných rádiových parametrů a rychlý rozvoj prostředků číslicového zpracování signálu v nedávné době, dnes umožňují ekonomicky přijatelné využití spektrálně efektivnějších modulačních technik i v těch oblastech, kde je prioritní využívání úzkých rádiových kanálů. Cílem předkládané disertační práce je proto výzkum postupů směřující ke sjednocení výhodných vlastností lineárních a nelineárních modulací v moderní konstrukci úzkopásmového rádiového modemu. Účelem tohoto výzkumu je efektivní a „ekologické“ využívání přidělené části frekvenčního spektra. Mezi hlavní dílčí problémy, jimiž se předkládaná práce zabývá, lze zařadit zejména tyto: Nyquistova modulační filtrace, navrhovaná s ohledem na minimalizaci nežádoucích elektromagnetických interferencí, efektivní číslicové algoritmy frekvenční demodulace a rychlé rámcové a symbolové synchronizace. Součástí práce je dále analýza navrhovaného řešení z pohledu celkové konstrukce programově definovaného rádiového modemu v rovině simulací při vyšetřování robustnosti datového přenosu rádiovým kanálem s bílým Gaussovským šumem nebo kanálem s únikem v důsledku mnohacestného šíření signálu. Závěr práce je pak zaměřen na prezentování výsledků praktické části projektu, v níž byly testovány, měřeny a analyzovány dvě prototypové konstrukce rádiového zařízení. Tato finální část práce obsahuje i praktická doporučení, vedoucí k vyššímu stupni využitelnosti spektrálně efektivnějších komunikačních režimů v oblasti budoucí generace úzkopásmových zařízení pozemní pohyblivé rádiové služby.he industrial narrowband land mobile radio (LMR) devices, as considered in this dissertation project, has been subject to European standard ETSI EN 300 113. The system operates on frequencies between 30 MHz and 1 GHz, with channel separations of up to 25 kHz, and is intended for private, fixed, or mobile, radio packet switching networks. Data telemetry, SCADA, maritime and police radio services; traffic monitoring; gas, water, and electricity producing factories are the typical system applications. Long distance coverage, high power efficiency, and efficient channel access techniques in half duplex operation are the primary advantages the system relays on. Very low level of adjacent channel power emissions and robust radio receiver architectures, with high dynamic range, enable for a system’s coexistence with various communication standards, without the additional guard band frequency intervals. On the other hand, the strict limitations of the referenced standard as well as the state of the technology, has hindered the increase in communication efficiency, with which the system has used its occupied bandwidth. New modifications and improvements are needed to the standard itself and to the up-to-date architectures of narrowband LMR devices, to make the utilization of more efficient modes of system operation practically realizable. The main objective of this dissertation thesis is therefore to find a practical way how to combine the favorable properties of the advanced nonlinear and linear digital modulation techniques in a single digital modem solution, in order to increase the efficiency of the narrowband radio channel usage allocated to the new generation of the industrial LMR devices. The main attention is given to the particular areas of digital modem design such as proposal of the new family of the Nyquist filters minimizing the adjacent channel interference, design and analysis of the efficient algorithms for frequency discrimination, fast frame and symbol

Efficient use of animal manures within an upland organic system (OF0187)

This is the final report of Defra project OF0187. The attached report starts with a detailed Executive Summary, from which this text is a short extract. The aim of this experiment (1999-2001) was to investigate the agronomic effects of applying treated and untreated farmyard manure and slurry to an organically managed, upland clover/ryegrass pasture. Seven main treatments were imposed in a split plot, randomised complete block design, simulating inputs from organic and conventional systems at ADAS Redesdale. The main treatments were; composted (Treatment A) and uncomposted (B) FYM; aerated (C) and unaerated (D) cattle slurry; ammonium nitrate (E); and a zero nitrogen control (F). A further control treatment (G), to which slurry was applied only in 1996, was added to provide a common control treatment during an earlier phase of the experiment. Target application rates were 150 kg total N/ha for untreated slurry and FYM treatments. Following aeration, the same volume of slurry as for the unaerated slurry treatments was applied. Allowing for losses, composted FYM was applied at a rate calculated to supply 80% (120 kg/ha) of total N compared to the untreated FYM treatment. Ammonium nitrate was used as a conventional control treatment, applied at an annual rate of 240 kg/N/ha. To determine the effect of phosphate and potash, one half of the plots were supplemented when soil levels of these nutrients fell below theoretically optimum levels. Highland Slag and Seagreen K were used as organic sources of P and K, while muriate of potash and superphosphate were used on the conventionally managed plots. Application rates were based on the results of soil analysis, according to standard recommendations for organic (Glenside Organics, Ltd) and conventional (Anon. 2000) production. Overall, the results indicate that high clover swards and the return of major nutrients in slurry and FYM can support a high level of productivity from an organically managed pasture, without the requirement for exogenous fertiliser inputs. Under a conservation system of management, it was clear that soil potassium could be a major limiting factor to herbage yield. However, FYM/slurry maintained an acceptable concentration of herbage K, despite a Soil Index of 0/1. The information generated on nutrient cycling, on output and other measures of productivity raises questions as to the optimum level of soil nutrients required for organic production, the role of soil microbial activity and the potential to better exploit composted FYM. The balance of crop offtake from more modest yields, with nutrients released from the soil, may dictate that high levels of extractable nutrients in the soil may not be a prerequisite for good performance from an organic system

Towards an Efficient Use of the BLAS Library for Multilinear Tensor Contractions

Mathematical operators whose transformation rules constitute the building blocks of a multi-linear algebra are widely used in physics and engineering applications where they are very often represented as tensors. In the last century, thanks to the advances in tensor calculus, it was possible to uncover new research fields and make remarkable progress in the existing ones, from electromagnetism to the dynamics of fluids and from the mechanics of rigid bodies to quantum mechanics of many atoms. By now, the formal mathematical and geometrical properties of tensors are well defined and understood; conversely, in the context of scientific and high-performance computing, many tensor- related problems are still open. In this paper, we address the problem of efficiently computing contractions among two tensors of arbitrary dimension by using kernels from the highly optimized BLAS library. In particular, we establish precise conditions to determine if and when GEMM, the kernel for matrix products, can be used. Such conditions take into consideration both the nature of the operation and the storage scheme of the tensors, and induce a classification of the contractions into three groups. For each group, we provide a recipe to guide the users towards the most effective use of BLAS.Comment: 27 Pages, 7 figures and additional tikz generated diagrams. Submitted to Applied Mathematics and Computatio

The movement of a forager: Strategies for the efficient use of resources

We study a simple model of a foraging animal that modifies the substrate on which it moves. This substrate provides its only resource, and the forager manage it by taking a limited portion at each visited site. The resource recovers its value after the visit following a relaxation law. We study different scenarios to analyze the efficiency of the managing strategy, corresponding to control the bite size. We observe the non trivial emergence of a home range, that is visited in a periodic way. The duration of the corresponding cycles and the transient until it emerges is affected by the bite size. Our results show that the most efficient use of the resource, measured as the balance between gathering and travelled distance, corresponds to foragers that take larger portions but without exhausting the resource. We also analyze the use of space determining the number of attractors of the dynamics, and we observe that it depends on the bite size and the recovery time of the resource

Efficient use of quantum resources for the transmission of a reference frame

We propose a covariant protocol for transmitting reference frames encoded on $N$ spins, achieving sensitivity $N^{-2}$ without the need of a pre-established reference frame and without using entanglement between sender and receiver. The protocol exploits the use of equivalent representations, which were overlooked in the previous literature.Comment: 4 pages, no figures; added new references and improved introduction. Accepted for publication on PR