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Direct memory access

Direct memory access is a feature of computer systems that allows certain hardware subsystems to access main system memory, independent of the central processing unit. Without DMA, when the CPU is using programmed input/output, it is fully occupied for the entire duration of the read or write operation, is thus unavailable to perform other work. With DMA, the CPU first initiates the transfer it does other operations while the transfer is in progress, it receives an interrupt from the DMA controller when the operation is done; this feature is useful at any time that the CPU cannot keep up with the rate of data transfer, or when the CPU needs to perform work while waiting for a slow I/O data transfer. Many hardware systems use DMA, including disk drive controllers, graphics cards, network cards and sound cards. DMA is used for intra-chip data transfer in multi-core processors. Computers that have DMA channels can transfer data to and from devices with much less CPU overhead than computers without DMA channels.

A processing element inside a multi-core processor can transfer data to and from its local memory without occupying its processor time, allowing computation and data transfer to proceed in parallel. DMA can be used for "memory to memory" copying or moving of data within memory. DMA can offload expensive memory operations, such as large copies or scatter-gather operations, from the CPU to a dedicated DMA engine. An implementation example is the I/O Acceleration Technology. DMA is of interest in network-on-chip and in-memory computing architectures. Standard DMA called third-party DMA, uses a DMA controller. A DMA controller can initiate memory read or write cycles, it contains several hardware registers that can be written and read by the CPU. These include a memory address register, a byte count register, one or more control registers. Depending on what features the DMA controller provides, these control registers might specify some combination of the source, the destination, the direction of the transfer, the size of the transfer unit, and/or the number of bytes to transfer in one burst.

To carry out an input, output or memory-to-memory operation, the host processor initializes the DMA controller with a count of the number of words to transfer, the memory address to use. The CPU commands peripheral device to initiate data transfer; the DMA controller provides addresses and read/write control lines to the system memory. Each time a byte of data is ready to be transferred between the peripheral device and memory, the DMA controller increments its internal address register until the full block of data is transferred. In a bus mastering system known as a first-party DMA system, the CPU and peripherals can each be granted control of the memory bus. Where a peripheral can become bus master, it can directly write to system memory without involvement of the CPU, providing memory address and control signals as required; some measure must be provided to put the processor into a hold condition so that bus contention does not occur. In burst mode, an entire block of data is transferred in one contiguous sequence.

Once the DMA controller is granted access to the system bus by the CPU, it transfers all bytes of data in the data block before releasing control of the system buses back to the CPU, but renders the CPU inactive for long periods of time. The mode is called "Block Transfer Mode"; the cycle stealing mode is used in systems in which the CPU should not be disabled for the length of time needed for burst transfer modes. In the cycle stealing mode, the DMA controller obtains access to the system bus the same way as in burst mode, using BR and BG signals, which are the two signals controlling the interface between the CPU and the DMA controller. However, in cycle stealing mode, after one byte of data transfer, the control of the system bus is deasserted to the CPU via BG, it is continually requested again via BR, transferring one byte of data per request, until the entire block of data has been transferred. By continually obtaining and releasing the control of the system bus, the DMA controller interleaves instruction and data transfers.

The CPU processes an instruction the DMA controller transfers one data value, so on. On the one hand, the data block is not transferred as in cycle stealing mode as in burst mode, but on the other hand the CPU is not idled for as long as in burst mode. Cycle stealing mode is useful for controllers. Transparent mode takes the most time to transfer a block of data, yet it is the most efficient mode in terms of overall system performance. In transparent mode, the DMA controller transfers data only when the CPU is performing operations that do not use the system buses; the primary advantage of transparent mode is that the CPU never stops executing its programs and the DMA transfer is free in terms of time, while the disadvantage is that the hardware needs to determine when the CPU is not using the system buses, which can be complex. This is called as "Hidden DMA data transfer mode". DMA can lead to cache coherency problems. Imagine a CPU equipped with a cache and an external memory that can be accessed directly by devices using DMA.

When the CPU accesses location X in the memory, the current value will be stored in the cache. Subsequent operations on X will update the cached copy of X, but not the external memory version of X, assuming a write-back cache. If the cache is not flushed to the memory before the next time a device tries to access X, the device will receive a stale value of X. Similarly, if the cached copy of X i

The Sweetest Dream

The Sweetest Dream is a 2001 novel by British Nobel Prize in Literature-winner Doris Lessing. The novel begins in the 1960s leading up to the 1980s and is set in London and the fictional African nation, Zimlia, a thinly veiled reference to Zimbabwe. In 1960s' Hampstead, the large home of Julia Lennox is a gathering place for an assortment of young and old characters. Frances Lennox finds herself living with her mother-in-law, Julia after her husband Johnny, a communist leader has abandoned her and his two sons and Colin to continue an affair with a glamorous "comrade"; the arrangement is difficult owing to the natures of both women, Frances is independent-minded and Julia betrays her German background and is more rigid. However both women are united in their disapproval of Johnny. Rather than working, Johnny's priorities are travelling and staying at hotels in communist countries and all the while continuing with his affairs. Frances gives up her theater ambitions for a more lucrative position on a liberal newspaper.

The Lennox household becomes filled with the classmates and dropout friends of her two sons now in secondary school. Frances acts as an earth-mother figure to the adolescents, offering a communal atmosphere so different from their strict family homes. Johnny maintains a presence in the household appearing to the benefits of free meals and the captive audience that the estranged adolescents provide at the kitchen table. Communist member, Rose Trimble is a regular addition until she turns gutter-press journalist and attacks Frances and Julia, branding them "imperialists". Other colourful characters that abound in the household include Johnny's anorexic daughter, two of Johnny's wives. Meanwhile and Andrew make their transition into adulthood. Colin becomes a novelist and Andrew, a graduate of the London School of Economics, becomes an illustrious international finance figure, working with the corrupt African leaders and other Third World countries in order to help funnel money to their poverty-stricken nations.

However Andrew is blind to the scale of the leaders' misuse of funding. Sylvia becomes a doctor, finds herself at a mission in Zimlia where the locals live in dire poverty and are crippled by the spread of AIDS; the new black leader of Zimlia and his wife are immensely wealthy, his ministers, as are his ministers such as the adult Franklin. These ministers continue to line their pockets as farms are expropriated from the nation's white farmers. Sylvia returns to England with two black boys; the boys move into the Lennox home where Frances is now in her early seventies, shares the home with Colin and his family. A now impoverished Johnny returns to the home, as communism is replaced by capitalism in the countries he once visited; the Independent described the work as a "rare literary pleasure the kind you might have in coming upon a long lost novel by George Eliot or Balzac." The review continued to appreciate the "haunting brilliance of her characters, whom one feels one knows rather better than one's friends, the passion of her ideas and vision, remain undiminished."

The Spectator described the work as "a startling, burningly committed book which, like all Lessing, contains a marvellous sense of possibilities opening as the fiction progresses, an enriching and absorbing conviction of change and growth." The Times described it as a "remarkable novel", notable for its "vigour and attack, for its passionate interest in justice and goodness." Lessing wrote The Sweetest Dream in place of volume three of her autobiography that would have covered the same time period. She decided against the autobiography lest she offend "vulnerable" people

Earl of Donoughmore

Earl of Donoughmore is a title in the Peerage of Ireland. It is associated with the Hely-Hutchinson family. Paternally of Gaelic Irish descent with the original name of Ó hÉalaighthe, their ancestors had long lived in the County Cork area as allies of the Mac Cárthaigh clan. One branch of the family converted to the Anglican Church and after inheriting territories through his mother and adding "Hutchinson" to Hely, became the Earl of Donoughmore; the title Earl of Donoughmore was created in 1800 for Richard Hely-Hutchinson, 1st Viscount Donoughmore, with remainder to the heirs male of his mother. He was a General in the British Army and sat in the House of Lords as one of the 28 original Irish Representative Peers from 1800 to 1825. Hely-Hutchinson had been created Viscount Donoughmore, of Knocklofty in the County of Tipperary, in the Peerage of Ireland in 1797, was made Viscount Hutchinson, of Knocklofty in the County of Tipperary, in the Peerage of the United Kingdom, in 1821; these titles were created with remainder to the heirs male of his mother.

Lord Donoughmore was the eldest son of the Irish statesman and lawyer John Hely-Hutchinson, who married Christiana, daughter of Abraham Nixon and niece and heiress of Richard Hutchinson of Knocklofty in County Tipperary, whose surname she and her husband adopted. In 1783 Christiana was raised to the Peerage of Ireland in honour of her husband as Baroness Donoughmore, of Knocklofty in the County of Tipperary; the first Earl was succeeded according to the special remainder by his younger brother, the second Earl. He was a General in the British Army. In 1801 he was created Baron Hutchinson, of Alexandria and Knocklofty in the County of Tipperary, in the Peerage of the United Kingdom, with remainder to the heirs male of his body. Lord Donoughmore served as Lord-Lieutenant of County Tipperary from 1831 to 1832. On his death in 1832 the barony of 1801 became extinct while he was succeeded in the other titles by his nephew, the third Earl, he was the son of the Honourable Francis Hely-Hutchinson, third son of the first Baroness Donoughmore and John Hely-Hutchinson.

He represented Tipperary in the House of Commons and served as Lord-Lieutenant of County Tipperary. He was succeeded by the fourth Earl, he was a Conservative politician and served in the Earl of Derby's second administration as Paymaster-General and President of the Board of Trade. His grandson, the fifth Earl, was a Conservative politician and held office as Under-Secretary of State for War from 1903 to 1904 under Arthur Balfour, he was succeeded by the sixth Earl, a noted Irish Freemason. His son, the seventh Earl, sat as Conservative Member of Parliament for Peterborough from 1943 to 1945; as of 2012 the titles are held by the latter's eldest son, the eighth Earl, who succeeded in 1981. Another member of the Hely-Hutchinson family was the Honourable Christopher Hely-Hutchinson, fifth son of Baroness Donoughmore and John Hely-Hutchison, he represented Cork City in the House of Commons. The Honourable Sir Walter Hely-Hutchinson, younger son of the fourth Earl, was the last Governor of the Cape Colony.

The Honourable Tim Hely Hutchinson, second son of the eighth Earl, is a publisher. The family seat now is The Manor House, near Oxfordshire; the former family seat was Knocklofty House, near Clonmel, County Tipperary, in Ireland, now a hotel. The Knocklofty Estate was sold by the family in the 1970s; the heir apparent to the earldom uses the invented courtesy title Viscount Suirdale. This derives from the fact that the territorial designation of the Irish viscountcy of Donoughmore was erroneously thought to be "of Suirdale". Christiana Hely-Hutchinson, 1st Baroness Donoughmore Richard Hely-Hutchinson, 2nd Baron Donoughmore Richard Hely-Hutchinson, 1st Earl of Donoughmore John Hely-Hutchinson, 2nd Earl of Donoughmore John Hely-Hutchinson, 3rd Earl of Donoughmore Richard John Hely-Hutchinson, 4th Earl of Donoughmore John Luke George Hely-Hutchinson, 5th Earl of Donoughmore Richard Walter Hely-Hutchinson, 6th Earl of Donoughmore John Michael Henry Hely-Hutchinson, 7th Earl of Donoughmore Richard Michael John Hely-Hutchinson, 8th Earl of Donoughmore The heir apparent is the present holder's eldest son John Michael James Hely-Hutchinson, Viscount Suirdale The heir apparent's heir apparent is his son Hon. Richard Gregory Hely-Hutchinson Kidd, Williamson, David.

Debrett's Baronetage. New York: St Martin's Press, 1990, Leigh Rayment's Peerage Pages

Besut (federal constituency)

Besut is a federal constituency in Terengganu, represented in the Dewan Rakyat since 1959. The federal constituency was created in the 1958 redistribution and is mandated to return a single member to the Dewan Rakyat under the first past the post voting system. 2004–2016: The constituency contains the polling districts of Pulau Perhentian, Seberang Barat, Kampung Nail, Seberang Barat Luar, Tok Saboh, Kampung Nangka, Kampung Baru, Bukit Puteri, Pekan Seberang Kastam, Seberang Kastam Luar, Kampung Raja Utara, Kampung Raja Selatan, Kampung Pinang, Amir Kampung Raja, Gong Bayur Tembila, Benting Lintang, Alur Lintang, Mukim Kubang Bemban, Alur Lintah, Tok Raja, Bukit Kenak, Gong Nering, Simpang Tiga Jertih, Bandar Jertih, Seberang Jertih, Padang Luas, Padang Landak, Cerang Meliling, Lubuk Kawah, Alur Keladi, Kampung Pasir Akar, Pasir Akar Luar, Mukim Tenang, LKTP Tenang, Kampung La, Hulu Besut. 2016–present: The constituency contains the polling districts of Pulau Perhentian, Seberang Barat, Seberang Barat Luar, Tok Saboh, Kampung Nangka, Kampung Baru, Bukit Puteri, Air Terjun, Pekan Seberang Kastam, Pengkalan Nyireh, Kampung Raja Utara, Kampung Raja Selatan, Batu Tumbuh, Gong Bayur, Beting Lintang, Alur Lintang, Gelam Mas, Kubang Bemban, Alur Lintah, Tok Raja, Bukit Kenak, Gong Nering, Simpang Tiga Jertih, Bandar Jertih, Seberang Jertih, Padang Luas, Padang Landak, Nyiur Tujuh, Gong Gucil, Cerang Meliling, Lubuk Kawah, Alur Keladi, Pasir Akar, Padang Bual, Bukit Payung, FELDA Tenang, Kampung La, Hulu Besut, Kayu Kelat.

"Keputusan Pilihan Raya Suruhanjaya Pilihan Raya". Election Commission of Malaysia. Retrieved 2018-08-12

Zambezi Belt

The Zambezi Belt is an area of orogenic deformation in southern Zambia and northern Zimbabwe. It is a segment of a broader belt lying between the Congo Craton and the Kalahari Craton, which includes the Lufilian Arc and the Damaran Belt; the eastern margin of the belt interacts with the north-south Eastern African orogen. The Zambezi belt shows evidence of two large tectonothermal events, one between about 890-880 Ma and the other about 550-520 Ma. Both events reworked existing Archean to Mesoproterozoic components, with small additions of younger material; the second event was caused by the collision of the Congo and Kalahari cratons during the assembly of the Gondwana supercontinent at the end of the Neoproterozoic. The belt includes the Kadunguri Whiteschists, which were formed by metasomatic alteration at high pressures of ocean-island-type metabasalts during the Pan-African orogeny; the Mwembeshi Shear Zone forms the northern boundary of the Zambezi Belt, separating it from the Lufilian Arc.

The shear zone dates to the Pan-African orogeny. It allowed a change in the structural vergence, or direction of folding, between the Zambezi Belt and the Lufilian Arc. Notes Citations Sources

Jack Wyant

John H. “Jack” Wyant is an American businessman and venture capitalist who founded Blue Chip Venture Company. In 1990. In 2013 he is its Managing Director. Wyant was raised in Hamilton and graduated from Garfield High School there in 1964, he attended Denison University from 1964 to 1968. Wyant was elected president of Phi Gamma Delta Fraternity in 1967, he led his local chapter to accept its first African American member in 1968. After graduating from Denison, Wyant worked in brand management at the Gamble Company. After Procter & Gamble, Wyant joined the Kings Island division of Taft Broadcasting Company. In 1975, he helped create and managed a joint venture with the National Football Foundation, which resulted in the design and operation of the College Football Hall of Fame. In 1977, he graduated from Salmon P. Chase College of Law of Northern Kentucky University with his juris doctorate. At Taft, he founded Blue Chip Broadcasting, a radio station group that grew to 20 stations including WIZF-FM.

He sold the company for $180 million. Wyant was the CEO of two venture-backed companies, Home Entertainment Network and Nutrition Technology Corporation. During this time he produced live sports and musical television specials, negotiated joint ventures, in 1980, he launched a TV network for the Cincinnati Reds, Chicago White Sox, Minnesota Twins and North Starts. In 1990, Wyant founded Blue Chip Venture Company. By 2013 Blue Chip had invested $600 million in over 125 companies through five venture funds, including internet service provider Digex, application service provider USinternetworking, ShareThis, a sharing service on 2 million websites and Richwood Pharmaceutical, developers of AdderallWyant is a member of investment group Queen City Angels, has direct investments in 20 private growth companies, is a founding investor and director of CBank and of Grandin Properties, a family owned real estate development and management firm of which his wife, Peg, is the CEO. Wyant is an investor in several sports enterprises, including the Major League Baseball franchise Cincinnati Reds and the United Soccer League franchise FC Cincinnati.

Wyant is a competitive squash player, is ranked in US Squash doubles and in 2010 won the national father-son doubles squash century level. In 2011, he served as the U. S. team captain against Canada. Wyant has written the books Corporate Governance Handbook for VCs. Wyant received a Denison Alumni citation for excellence in entrepreneurship in 1988, the Seal of the City, Cincinnati's highest honor in 1993, a Lifetime Achievement award from the Greater Cincinnati Venture Association in 2002 for creating the venture capital industry in Cincinnati. In 2007 the Association for Corporate Growth awarded him the Master Dealmaker Award. "Executive Profile John H. Wyant J. D." Bloomberg Businessweek. Retrieved 6 February 2013