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Antenna gain

In electromagnetics, an antenna's power gain or gain is a key performance number which combines the antenna's directivity and electrical efficiency. In a transmitting antenna, the gain describes how well the antenna converts input power into radio waves headed in a specified direction. In a receiving antenna, the gain describes how well the antenna converts radio waves arriving from a specified direction into electrical power; when no direction is specified, "gain" is understood to refer to the peak value of the gain, the gain in the direction of the antenna's main lobe. A plot of the gain as a function of direction is called the gain radiation pattern. Antenna gain is defined as the ratio of the power produced by the antenna from a far-field source on the antenna's beam axis to the power produced by a hypothetical lossless isotropic antenna, sensitive to signals from all directions; this ratio is expressed in decibels, these units are referred to as "decibels-isotropic". An alternative definition compares the received power to the power received by a lossless half-wave dipole antenna, in which case the units are written as dBd.

Since a lossless dipole antenna has a gain of 2.15 dBi, the relation between these units is G a i n = G a i n − 2.15 For a given frequency, the antenna's effective area is proportional to the power gain. An antenna's effective length is proportional to the square root of the antenna's gain for a particular frequency and radiation resistance. Due to reciprocity, the gain of any reciprocal antenna when receiving is equal to its gain when transmitting. Directive gain or directivity is a different measure which does not take an antenna's electrical efficiency into account; this term is sometimes more relevant in the case of a receiving antenna where one is concerned with the ability of an antenna to receive signals from one direction while rejecting interfering signals coming from a different direction. Power gain is a unitless measure that combines an antenna's efficiency ϵ a n t e n n a and directivity D: G = ϵ a n t e n n a ⋅ D; the notions of efficiency and directivity depend on the following.

A transmitting antenna accepts input power P i n at some point along the feedline. The point is taken to be at the antenna, thereby not counting power lost due to joule heating in the feedline and reflections back down the feedline; the efficiency ϵ a n t e n n a of an antenna is the total radiated power P o divided by the input power at the feedpoint ϵ a n t e n n a = P o P i n The electromagnetic reciprocity theorem guarantees that the electrical properties of an antenna, such as efficiency and gain, are the same when the antenna is used for receiving as when it is transmitting. Antennas are invariably directional to a greater or lesser extent, according to how the output power is distributed in any given direction in three dimensions. We shall specify direction here in spherical coordinates, where θ is the altitude or angle above a specified reference plane, while ϕ is the azimuth as the angle between the projection of the given direction onto the reference plane and a specified reference direction in that plane with specified sign.

The distribution of output power as a function of the possible directions is given by its radiation intensity U. The output power is obtained from the radiation intensity by integrating the latter over all solid angles d Ω = sin ⁡ θ d θ d ϕ: P o = ∫ − π π ∫ − π / 2 π / 2 U d Ω = ∫ − π π ∫ − π / 2 π / 2 U sin ⁡ θ d θ d ϕ. {\displaystyle P_=\int _^\int _^{\pi /2

The Sunday People

The Sunday People is a British tabloid Sunday newspaper. It was founded as The People on 16 October 1881; the People was bought by the Mirror group in 1961, along with the Daily Herald. It is now published by Reach plc, shares a website with the Mirror papers. In July 2011, when it benefited from the closure of the News of the World, it had an average Sunday circulation of 806,544. By December 2016 the circulation had shrunk to 239,364. Despite its tagline claim to be a "truly independent" newspaper, the People endorsed the Labour Party at the 2015 general election on the recommendation of polling data from its readers. Garry Bushell had a two-page television opinion column, "Bushell on the Box", but left in early 2007 moving to the Daily Star Sunday. Jimmy Greaves, the former England footballer Fred Trueman, former England cricketer and fast bowler Fred Harrison, an established economics author of 19 books

Reaction to the 2010 CopiapĆ³ mining accident

The 2010 Copiapó mining accident occurred when the San Jose Mine near to Copiapó, collapsed, leaving 33 miners of Chilean nationality and one Bolivian miner trapped inside about 700 metres below the surface. The men were trapped in the mine for 69 days before being rescued; the discovery of the miners and their eventual rescue received global attention, with over 2000 members of the media reporting from the San Jose Mine. Global leaders expressed good wishes for the rescue and congratulations upon its successful completion. Chile Chilean President Sebastián Piñera and First Lady Cecilia Morel were present during the rescue, greeting each of the miners individually as they emerged from the mine. Bolivian President Evo Morales was scheduled to be on location for the rescue but did not arrive in time for the rescue of the trapped Bolivian miner, Carlos Mamani. During a visit to Europe following the rescue, Piñera was offered an audience with Queen Elizabeth II, who extended an invitation at the last minute following the mine rescue.

He presented her with a rock from the mine as a gift. After all the miners were rescued, Piñera gave a speech on location in which he was effusive in his praise of Chile and said he was "proud to be the president of all Chileans." He invoked Chile's passed bicentennial celebrations and said the miners were rescued with "unity and faith." He thanked Chávez and Morales, amongst others for their call for support. He said those who forced the rescue, i.e. those responsible for the collapse of the mine, will be punished, said there would be a "new deal" with the workers. The incident generated interest both within Chile and internationally, with the miners being declared heroes by many people. Firestations rang sirens across Chile in celebration after the final rescue. In Copiapo, thousands of people cheered and wept during the rescue as people chanted "Long live Chile."The rescue operation was broadcast live on various news networks and international media. The reaction from world media was enthusiastic, the rescue made the front pages of newspapers worldwide: not only was the rescue from the greatest depth of any such operation but the miners had waited to be found – let alone rescued – longer than any other survivors, in their predicament.

RussiaThe rescue of the miners led to Russian bloggers asking why their country did not have a similar success story after a string of tragedies. The last Russian mining catastrophe in May 2010 took the lives of 90 miners and rescue workers at the Raspadskaya mine near Mezhdurechensk, in southern Siberia, with safety breaches blamed for the disaster."The miner rescue operation is completed in Chile helped by the fact that Sergei Shoigu did not participate in it," wrote blogger xeyrulla on his LiveJournal blog. President Dmitry Medvedev said in a message to his Chilean counterpart Sebastián Piñera that the operation is "proof that any the most difficult challenges can be overcome by the will and courage of people united by the same goal". ChinaEscape capsules and shelter facilities were discussed in China after the news was released of the 33 Chilean miners being pulled to safety. An underground mine rescue chamber is believed to have played a key role. Luo Lin, head of the State Administration of Work Safety, made the remark at a meeting in Henan province after a gas leak killed 37 miners there.

Mines in China were to have underground escape capsules and other emergency facilities by 2015, according to a previous administration work schedule. The Changcun coal mine, which belongs to Shanxi's Lu'an Group, has been equipped with 16 underground escape capsules and seven shelter rooms, it was China's first mine with such safety facilities, China Youth Daily reported over the weekend. The capsule is a steel structure measuring 6.3 meters by 1.4 meters by 1.8 meters and can withstand the impact of a gas explosion. It has its own oxygen supply, air purifier and air conditioner and can keep 12 miners alive for 96 hours, according to the report. Rest of the world A number of foreign leaders contacted Piñera to express solidarity and pass on congratulations to Chile while the rescue efforts were ongoing, including the Presidents of Argentina, Cristina Fernández de Kirchner. Leaders including United States President Barack Obama, British Prime Minister David Cameron and Pope Benedict XVI offered congratulations to the coordinators of the rescue attempt and to the miners themselves for their bravery.

Cameron said during Prime Minister's Questions at the House of Commons: President of the United States Barack Obama telephoned Piñera to pay tribute to the miners, rescue workers, the government and the Chilean nation. UN Secretary General Ban Ki Moon spoke to Pinera the day after the rescue, his spokesman Martin Nersirsky said: South African President Jacob Zuma said: The government provided exclusive non-stop television coverage of the rescue, available for free to broadcasters around the world. The contract was won by state-owned television station TVN; the government signal offered live views from inside the mine as the rescue capsule reached its destination. The rescue was according to internet monitors. Internet monitor Akamai said overall web traffic was 20 per cent higher than normal around the time the first Chilean miner was rescued late Tuesday, while the company's Net Usage Index for News indicated that the Chilean mine rescue was the fifth

Dearfield, Colorado

Dearfield is a ghost town and a black majority settlement in Weld County, United States. It is 30 miles east of Greeley; the town was formed by Oliver Toussaint Jackson, who desired to create a colony for African Americans. In 1910, Jackson, a successful businessman from Boulder, filed on the homestead that became the town and began to advertise for "colonists." The name Dearfield was suggested by one of the town's citizens, Dr. J. H. P. Westbrook, from Denver; the word dear was chosen as the foundation for the town's name due to the precious value of the land and community to the town's settlers. The first settlers of Dearfield had great difficulty farming the surrounding pasture and endured several harsh seasons. By 1920, the town had two churches, a school and restaurant. In 1921, the town's net worth was appraised at $1,075,000. After the prosperous years of the 1920s, the Great Depression arrived and the town's agricultural success declined. Settlers began to leave Dearfield in order to find better opportunities.

By 1940, the town population had decreased to 12. Jackson attempted to spur interest in the town offering it for sale. However, there was little interest in Dearfield. Jackson died on February 18, 1948. A few deserted buildings remain in Dearfield: a gas station, a diner, the founder's home. In 1995, the town was listed on the National Register of Historic Places. In 1998, Black American West Museum in Denver began to make attempts to preserve the town's site, it is a Colorado Registered Historic Landmark. A 2010 monument next to one of the remaining buildings contains information about the history of the site. A 2001 state historical marker at U. S. Route 85 mile marker 264 near Evans, includes a panel with the history of Dearfield. National Register of Historic Places listings in Weld County, Colorado Allensworth, California Boley, Oklahoma Nicodemus, Kansas University of Northern Colorado Libraries: Dearfield Dearfield Colony listing in Colorado Preservation's Endangered Places Program Dearfield African-American Farming Colony page at Colorado State University's Architectural Preservation Institute Edwards, Richard.

"The disappearing story of the black homesteaders who pioneered the West". Washington Post. Retrieved 8 July 2018

Warleggan

Warleggan or Warleggon is a civil parish on the southern edge of Bodmin Moor in Cornwall, United Kingdom. The parish is oblong in shape with hamlets near the church and at Mount; the River Warleggan, a tributary of the River Fowey, runs through the parish, forming its western boundary in places. The population was 203 in the 2001 census, had increased to 208 at the 2011 census; the population in 1801 was 116. A road was built in 1953 linking Warleggan to the A38; the parish church is Norman and 15th century in date. It had a spire but this fell down in 1818 and was not rebuilt; the church consists of a chancel and south aisle with a granite arcade. From 1931 until his death the Rev. Frederick W. Densham was Rector of Warleggan: he was unworldly and eccentric; the film A Congregation of Ghosts is based on his life. There is a Cornish cross in the churchyard. In 1858 it was found on Warleggan Down between Treveddoe. There is a former Methodist chapel in the parish. Cabilla Manor Wood, in the west of the civil parish, is a Site of Special Scientific Interest noted for its biological interest.

The SSSI surrounds the River Warleggan. Media related to Warleggan at Wikimedia Commons

Michael Drayton

Michael Drayton was an English poet who came to prominence in the Elizabethan era. Drayton was born at Hartshill, near Nuneaton, England. Nothing is known about his early life, beyond the fact that in 1580 he was in the service of Thomas Goodere of Collingham, Nottinghamshire. Nineteenth- and twentieth-century scholars, on the basis of scattered allusions in his poems and dedications, suggested that Drayton might have studied at the University of Oxford, been intimate with the Polesworth branch of the Goodere family. More recent work has cast doubt on those speculations. In 1590 he produced his first book, The Harmony of the Church, a volume of spiritual poems, dedicated to Lady Devereux, it is notable for a version of the Song of Solomon, executed with considerable richness of expression. However, with the exception of forty copies, seized by the Archbishop of Canterbury, the whole edition was destroyed by public order. Drayton published a vast amount within the next few years. In 1593 appeared Idea: The Shepherd's Garland, a collection of nine pastorals, in which he celebrated his own love-sorrows under the poetic name of Rowland.

The basic idea was expanded in a cycle of sixty-four sonnets, published in 1594, under the title of Idea's Mirror, by which we learn that the lady lived by the river Ankor in Warwickshire. It appears that he lived and died a bachelor, it has been said Drayton's sonnets possess a direct and universal appeal, by reason of their simple straightforward ring and foreshadowed the smooth style of Fairfax and Dryden. Drayton was the first to bring the term ode, for a lyrical poem, to popularity in England and was a master of the short, staccato Anacreontics measure. In 1593 there appeared the first of Drayton's historical poems, The Legend of Piers Gaveston, the next year saw the publication of Matilda, an epic poem in rhyme royal, it was about this time, that he brought out Endimion and Phoebe, a volume which he never republished, but which contains some interesting autobiographical matter, acknowledgments of literary help from Thomas Lodge, if not from Edmund Spenser and Samuel Daniel also. In his Fig for Momus, Lodge reciprocated these friendly courtesies.

In 1596 Drayton published his long and important poem Mortimeriados, a serious production in ottava rima. He enlarged and modified this poem, republished it in 1603 under the title of The Barons' Wars. In 1596 appeared another historical poem, The Legend of Robert, Duke of Normandy, with which Piers Gaveston was reprinted. In 1597 appeared England's Heroical Epistles, a series of historical studies, in imitation of those of Ovid; these last poems, written in the heroic couplet, contain some of the finest passages in Drayton's writings. By 1597, the poet was resting on his laurels, it seems that he was much favoured at the court of Elizabeth, he hoped that it would be the same with her successor. But when, in 1603, he addressed a poem of compliment to James I, on his accession, it was ridiculed, his services rudely rejected, his bitterness found expression in a satire, The Owl, but he had no talent in this kind of composition. Not much more entertaining was his scriptural narrative of Moses in a Map of his Miracles, a sort of epic in heroics printed the same year.

In 1605 Drayton reprinted his most important works, his historical poems and the Idea, in a single volume which ran through eight editions during his lifetime. He collected his smaller pieces, hitherto unedited, in a volume undated, but published in 1605, under the title of Poems Lyric and Pastoral; some of the odes are spirited. In this volume he printed for the first time the famous Ballad of Agincourt, he had adopted as early as 1598 the extraordinary resolution of celebrating all the points of topographical or antiquarian interest in the island of Great Britain, on this laborious work he was engaged for many years. At last, in 1613, the first part of this vast work was published under the title of Poly-Olbion, eighteen books being produced, to which the learned Selden supplied notes; the success of this great work, which has since become so famous, was small at first, not until 1622 did Drayton succeed in finding a publisher willing to undertake the risk of bringing out twelve more books in a second part.

This completed the survey of England, the poet, who had hoped "to crown Scotland with flowers," and arrive at last at the Orcades, never crossed the Tweed. In 1627 he published another of his miscellaneous volumes, this contains some of his most characteristic writing, it consists of the following pieces: The Battle of Agincourt, an historical poem in ottava rima, The Miseries of Queen Margaret, written in the same verse and manner. Nimphidia is the most critically acclaimed, along with his famous ballad on the battle of Agincourt; the last of Drayton's voluminous publications was The Muses' Elizium in 1630. He died in London, was buried in Poets' Corner in Westminster Abbey, had a monument placed over him by the Countess of Dorset, with memorial lines attributed to Ben Jonson. Like other poets of his era, Drayton was active in writing for the theatre. For a period of only five years, from 1597 to 1602, Drayton was a member of the sta