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  Decarbonising End-use Sectors:...

  Irena International Renewable...

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  This brief, developed by the IRENA Coalition for Action, provides an overview of technical considerations for green hydrogen tracking systems and the challenges that need to be addressed for the creation of such instruments.

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  The Sun's Babies

  Edith Howes

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  Charming stories and poems for young children about nature and the changes that occur with the seasons, weaving in life lessons throughout the stories. (Summary by Laura Victoria)

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  Gotcha Day! - Adoption Tales of...

  Greg Murray

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  Meet Killian who is obsessed with clothes and just has to find the right outfit each morning; Jet who snores louder than a human; and Roger, who came to his family from a puppy mill and learned that people can be kind and loving. Gotcha Day! spotlights the adoption tales of over 60 adorable rescue dogs and their new forever families. The unique personality of each pup shines through the candid photos by animal advocate and photographer Greg Murray, and their humans let us in on their inspiring stories, funny quirks, and all the many things that make them special.

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  Reactive Power Compensation

  Dr. Hidaia Mahmood Alassoulii

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  Power systems have two components of apparent power: active and reactive power. Both components are necessary for functioning of electrical systems. The active power is the average power absorbed by the resistive load. The reactive power is the measure of energy exchange between the source and reactive power of load. Energy storage devices do not dissipate or supply power, but exchange power with the rest of system. Active power is the one that is converted to other forms of energy in the load yet reactive power is only responsible for magnetizing purposes.  Power factor is a ratio depicting how much of the power supplied is real. The reactive current contribute in the value of the overall magnitude of current in transmission lines causing unnecessarily high line currents and low power factor. Since a low power factor means higher amount of apparent power need to be supplied by the utility company, thus the company must also use bigger generators, large transformers and thicker transmission/distribution lines. This requires a higher capital expenditure and operational cost which usually result in the cost being passed to the consumer.In this research, we seek to identify the effects of a low power factor on Swaziland Electricity Companys power supply system and recommend possible solutions to the problem. The results are useful in determining how to optimally deliver power to a load at a power factor that is reasonably close to unity, thus reducing the utilitys operational costs while increasing the quality of the service being supplied.

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  Frankforce and the Defence of...

  Jerry Murland

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  There is no other city in France that has the same associations in time of conflict that the British have with Arras. Since the campaigns of John Churchill, 1st Duke of Marlborough, in the early 18th century, British soldiers have fought in and around Arras, occasionally as an enemy but, more often, as defenders of French and Allied democracy. Battlefield visitors to the area will immediately recognize the names of towns and villages that were as significant to the men of Marlboroughs army as they were to those who fought in the First and Second World Wars.This book serves both as guide to the Second World War battlefields that surround the city and its environs as well as detailing the actions of the British armored attack of 21 May 1940. The book looks at the strategic situation that led up to the famous Arras counterstroke and, using material that has not been published before, examines the British and German actions between 20 and 23 May. The only Victoria Cross action that took place during this time is looked at in detail; as is the fighting that took place in Arras and during the breakout.Despite its shortcomings, the counterstroke achieved the essential element of surprise and caused widespread alarm amongst the German command and hit Rommels 7th Panzer Division at precisely the moment when his armored units were ahead of the infantry and gunners. The British infantry fought well and both the Durham battalions were fortunate that their commanding officers and senior NCOs were men who had already fought in one conflict and possessed the determination to rally their less experienced junior ranks and fight on regardless. Such was the case with the two tank battalions, although sadly they lost both their commanding officers and over half the tanks that went into the engagement. The attack did enable the British to tighten their hold on Arras  albeit temporarily  and, as is often cited, built doubts in the minds of German High Command as to the speed of their advance and contributed to the subsequent Hitler halt order of 24-27 May.The author has gone to some lengths to track down accounts from those individuals who served in the area during May 1940 and fought the enveloping tide of the German advanceThe book is supported by three car tours, one of which takes the visitor along the tragic path taken by the Tyneside Scottish on 20 May and two walking routes, which concentrate on Arras.137 black and white photographs (integrated) and a number of maps derived from regimental histories; and six tour maps provide the battlefield visitor with illustrations of the battlefields as they were in 1940 and as they are today.

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  The Eerie Silence - Renewing Our...

  Paul Davies

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  Fifty years ago, a young astronomer named Frank Drake pointed a radio telescope at nearby stars in the hope of picking up a signal from an alien civilization. Thus began one of the boldest scientific projects in history, the Search for Extraterrestrial Intelligence (SETI). But after a half century of scanning the skies, astronomers have little to report but an eerie silence-eerie because many scientists are convinced that the universe is teeming with life. The problem, argues leading physicist and astrobiologist Paul Davies, is that we've been looking in the wrong place, at the wrong time, and in the wrong way. Davies should know. For more than three decades, he has been closely involved with SETI and now chairs the SETI Post-Detection Taskgroup, charged with deciding what to do if we're confronted with evidence of alien intelligence. In this extraordinary book, he shows how SETI has lost its edge, then offers a new and exciting road map for the future.Davies believes that our search so far has been overly anthropocentric: we tend to assume an alien species will look, think, and behave like us. He argues that we need to be far more expansive in our efforts, and in this book he completely redefines the search, challenging existing ideas of what form an alien intelligence might take, how it might try to communicate with us, and how we should respond if we ever do make contact. A provocative and mind-expanding journey, The Eerie Silence will thrill fans of science and science fiction alike.

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