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Daylight saving time in the United States
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Ohio Clock in the U.S. Capitol being turned forward for the country's first daylight saving time in 1918
Daylight saving time in the United States is the practice of setting the clock forward by one hour during the warmer part of the year, so that evenings have more daylight and mornings have less. Most areas of the United States observe daylight saving time (DST), the exceptions being Arizona (except for the Navajo, who do observe daylight saving time on tribal lands),[1] Hawaii,[2] and the overseas territories of American Samoa, Guam, the Northern Mariana Islands, Puerto Rico, and the United States Virgin Islands.
In general, daylight saving time is not observed in lower-latitude regions, as summer days are not much longer than winter ones as in higher latitudes.
Daylight saving time starts on the second Sunday in March and ends on the first Sunday in November, with the time changes taking place at 2:00 a.m. local time. With a mnemonic word play referring to seasons, clocks "spring forward, fall back" —that is, in springtime the clocks are moved forward from 2:00 a.m. to 3:00 a.m. and in fall they are moved back from 2:00 a.m. to 1:00 a.m. Daylight saving time lasts for a total of 34 weeks (238 days) every year, about 65% of the entire year.
The following table lists recent past and near future starting and ending dates of daylight saving time in the United States:
Year
Start
End
2015 March 8 November 1
2016 March 13 November 6
2017 March 12 November 5
2018 March 11 November 4
2019 March 10 November 3
2020 March 8 November 1
2021 March 14 November 7
2022 March 13 November 6
2023 March 12 November 5
2024 March 10 November 3
Contents
[hide]
1 History of DST in the United States
1.1 1916–1966: Early, inconsistent use
1.2 1966–1972: Federal standard established
1.3 1973–1975: Year-round experiment
1.4 1975–1986: Extension of daylight saving time
1.5 2005–2009: Second extension
2 Procedure for modifications
2.1 Changing an area's time zone
2.2 Moving an area on or off DST
3 Local DST observance
3.1 Alaska
3.2 Arizona
3.2.1 Reservations in Arizona
3.3 California
3.4 Florida
3.5 Hawaii
3.6 Indiana
3.7 Michigan
3.8 Nevada
3.9 Washington
3.10 Other U.S. locations
4 Time zones
5 See also
6 References
7 External links
History of DST in the United States[edit]
Benjamin Franklin proposed a form of daylight time in 1784. His essay, “An Economical Project for Diminishing the Cost of Light”, written to the editor of The Journal of Paris, observed that Parisians could save on candles by getting out of bed earlier in the morning, making use of the natural morning light instead. Franklin's suggestion seems to have been more of a joke than a real proposal, and nothing came of it.[3]
1916–1966: Early, inconsistent use[edit]
During World War I, in an effort to conserve fuel, Germany began observing DST on May 1, 1916. The rest of Europe soon followed. The plan was not adopted in the United States until the Standard Time Act of March 19, 1918, which confirmed the existing standard time zone system and set summer DST to begin on March 31, 1918 (reverting October 27).[4] The idea was unpopular and Congress abolished DST after the war, overriding President Woodrow Wilson's veto.[5] DST became a local option and was observed in some states until World War II, when President Franklin Roosevelt instituted year-round DST, called "War Time", on February 9, 1942.[6] It lasted until the last Sunday (the 30th) in September 1945. After 1945 many states and cities east of the Mississippi River (and mostly north of the Ohio and Potomac rivers) adopted summer DST.[7]
From 1945 to 1966 there was no federal law on daylight saving time, so localities could choose when it began and ended or drop it entirely. As of 1954, only California and Nevada had statewide DST west of the Mississippi, and only a few cities between Nevada and St. Louis. In the 1964 Official Railway Guide, 21 of the 48 states had no DST anywhere.
1966–1972: Federal standard established[edit]
By 1962, the transportation industry found the lack of consistency confusing enough to push for federal regulation. The result was the Uniform Time Act of 1966 (P.L. 89-387). Beginning in 1967, the act mandated standard time within the established time zones and provided for advanced time: clocks would be advanced one hour beginning at 2:00 a.m. on the last Sunday in April and turned back one hour at 2:00 a.m. on the last Sunday in October. States were allowed to exempt themselves from DST as long as the entire state did so. If a state chose to observe DST, the time changes were required to begin and end on the established dates. In 1967, Arizona and Michigan became the first states to exempt themselves from DST (Michigan would begin observing DST in 1972). In 1972, the act was amended (P.L. 92-267), allowing those states split between time zones to exempt either the entire state or that part of the state lying within a different time zone. The newly created Department of Transportation (DOT) was given power to enforce the law. As of 2014, the following states and territories are not observing DST: Arizona, Hawaii, American Samoa, Puerto Rico, and the Virgin Islands.[7]
1973–1975: Year-round experiment[edit]
During the 1973 oil embargo by the Organization of Arab Petroleum Exporting Countries (OAPEC), in an effort to conserve fuel, Congress enacted a trial period of year-round DST (P.L. 93-182), beginning January 6, 1974, and ending April 27, 1975.[8] The trial was hotly debated. Those in favor pointed to increased daylight hours in the winter evening: more time for recreation, reduced lighting and heating demands, reduced crime, and reduced automobile accidents. The opposition was concerned about children leaving for school in the dark. The act was amended in October 1974 (P.L. 93-434) to return to standard time for the period beginning October 27, 1974, and ending February 23, 1975, when DST resumed. When the trial ended in 1975, the country returned to observing summer DST (with the aforementioned exceptions).[7]
1975–1986: Extension of daylight saving time[edit]
The DOT, evaluating the plan of extending DST into March, reported in 1975 that "modest overall benefits might be realized by a shift from the historic six-month DST (May through October) in areas of energy conservation, overall traffic safety and reduced violent crime." However, DOT also reported that these benefits were minimal and difficult to distinguish from seasonal variations and fluctuations in energy prices.[7]
Congress then asked the National Bureau of Standards (NBS, today NIST) to evaluate the DOT report. Its report, "Review and Technical Evaluation of the DOT Daylight Saving Time Study" (April 1976), found no significant energy savings or differences in traffic fatalities.[9] It did find statistically significant evidence of increased fatalities among school-age children in the mornings during the four-month period January–April 1974 as compared with the same period (non-DST) of 1973. NBS stated that it was impossible to determine, what, if any, of this increase was due to DST. When these data were compared between 1973 and 1974 for the months of March and April, no significant difference was found in fatalities among school-age children in the mornings.[7]
In 1986 Congress enacted P.L. 99-359, amending the Uniform Time Act by changing the beginning of DST to the first Sunday in April and having the end remain the last Sunday in October.[7] These start and end dates were in effect from 1987 to 2006. The time was adjusted at 2:00 a.m. local time.
2005–2009: Second extension[edit]
By the Energy Policy Act of 2005, daylight saving time (DST) was extended in the United States beginning in 2007.[10] As from that year, DST begins on the second Sunday of March and ends on the first Sunday of November. In years when April 1 falls on Monday through Wednesday, these changes result in a DST period that is five weeks longer; in all other years the DST period is instead four weeks longer.[11] In 2008 daylight saving time ended at 2:00 a.m. DST (0200) (1:00 a.m. ST) on Sunday, November 2, and in 2009 it began at 2:00 a.m. (3:00 a.m. DST) on Sunday, March 8.[12] Wyoming Senator Michael Enzi and Michigan Representative Fred Upton advocated the extension from October into November especially to allow children to go trick-or-treating in more daylight.[13]
Under Section 110 of the Act, the U.S. Department of Energy was required to study the impact of the 2007 DST extension no later than nine months after the change took effect. The report, released in October 2008, reported a nationwide electricity savings of 0.03% for the year of 2007.[14]
An October 2008 study conducted by the University of California at Santa Barbara for the National Bureau of Economic Research found that the 2006 DST adoption in Indiana increased energy consumption in Indiana by an average of 1%. Although consumption for lighting dropped as a result of the DST adoption, consumption for heating and cooling increased by 2% to 4%. The cost to the average Indiana household of the DST adoption was determined to be $3.29 per year, for an aggregate cost of $1.7 million to $5.5 million per year.[15]
Procedure for modifications[edit]
Changing an area's time zone[edit]
Under the Standard Time Act of 1918, as amended by the Uniform Time Act of 1966, moving a state or an area within a state from one time zone to another requires a regulation issued by DOT. The governor or state legislature may initiate a request for the state or any part of the state; the highest elected officials in the county may make a request for that county. The standard in the statute for such decisions is the convenience of commerce in that area. The convenience of commerce is defined broadly to consider such circumstances as the shipment of goods within the community; the origin of television and radio broadcasts; the areas where most residents work, attend school, worship, or receive health care; the location of airports, railway, and bus stations; and the major elements of the community's economy.[7]
After receiving a request for altering a time zone, DOT determines whether it meets the requirement of minimum statutory criteria before issuing a notice of proposed rulemaking, soliciting public comment and scheduling a public hearing. Usually the hearing is held in the area requesting the change so that all affected parties can be represented. After the close of the comment period, the comments are reviewed and appropriate final action taken. If the Secretary agrees that the statutory requirement has been met, the change is instituted, usually at the next changeover to or from DST.[7]
Moving an area on or off DST[edit]
Under the Uniform Time Act, moving an area on or off DST is accomplished through legal action at the state level. Some states require legislation while others require executive action such as a governor's executive order. Information on procedures required in a specific state may be obtained from that state's legislature or governor's office. Although it may exempt itself, if a state decides to observe DST, the dates of observance must comply with federal legislation.[7]
Local DST observance[edit]
Alaska[edit]
This section needs to be updated. Please update this article to reflect recent events or newly available information. (November 2017)
Alaska observes DST. Due to its high latitude, Alaska has nearly round-the-clock daylight during summer, and DST is seen by some Alaskans as unnecessary and a nuisance. Another issue is that the Alaskan mainland's single time zone, which approximates solar time in the capital, Juneau, leads to a large disparity between civil time and solar time for much of the state, with solar noon occurring as late as 2:00 p.m. in the population centers of Anchorage and Fairbanks, and as late as 3:00 p.m. in places such as Nome. In Fairbanks, for example, sunset occurs well after civil midnight in the summer. Others argue that ending daylight saving time will place Alaska as much as five hours from Eastern Daylight Time, making coordination of travel and phone conversations more difficult.
In March 2015 the Alaska Senate passed a bill, introduced by state senator Anna MacKinnon, to end daylight saving time. The Alaska House formed a sub-committee that was due to look into the issue during the 2016 legislative session.[16]
Arizona[edit]
Arizona observed DST in 1967 under the Uniform Time Act because the state legislature did not enact an exemption statute that year. In March 1968 the DST exemption statute was enacted and the state of Arizona has not observed DST since 1967. This is in large part due to an effort to conserve energy. Phoenix and Tucson are among the hottest U.S. metropolitan areas during the summer, resulting in more power usage from air conditioning units and evaporative coolers in homes and businesses. An extra hour of sunlight while people are active would cause people to run their cooling systems longer, thereby using more energy.[17]
Reservations in Arizona[edit]
The Navajo Indian Reservation extends into Utah and New Mexico and does observe daylight saving time.[18] The Hopi Reservation is entirely within the state of Arizona and is an enclave within the Navajo Indian Reservation, but does not observe DST.
California[edit]
California voters passed Proposition 12[19] in 1949, approving DST in the state.[20] In February 2017, California Assembly member Kansen Chu introduced A.B. 807,[21] which, if enacted and approved by voters, would enable the legislature to eliminate DST in the state, or, if federal law allows, to adopt DST for the entire year..[22]
Florida[edit]
Daylight time is less useful in Florida than in many other states because its southern location leads to less variation in day length between winter and summer. Without DST, Miami, for instance, would experience similar sunrise and sunset times throughout the year to cities such as Honolulu or Hong Kong, both of which have abandoned DST for decades. There is opposition to DST in Florida.[23] State senator Bill Posey introduced a bill in March 2008 to abolish daylight time in the state and keep Florida on year-round standard time.[24] Because Florida straddles two time zones, the Florida legislature has the option of returning all or part of the state to standard time along time zone boundaries (i.e. placing the portion of the state in the Eastern time zone on standard time, while leaving the portion in the Central time zone on DST, so that the whole state had a common time).
Hawaii[edit]
Hawaii has never observed daylight saving time under the Uniform Time Act, having opted out of the Act's provisions in 1967.[25]
Because of Hawaii's tropical latitude, there is not a large variation in daylight length between winter and summer. Advancing the clock in Hawaii would make sunrise times close to 7:00 a.m. even in June.[26] Most of the inhabited islands are located close to the west end of the Hawaii-Aleutian time zone, but Oahu, Kauai, and Niihau are located more than 7 degrees west of the Hawaii-Aleutian time zone's meridian and should, theoretically, be located in the next time zone to the west. (Until about 1946 Hawaiian standard time was based on longitude 157.5 degrees west rather than 150 degrees.)
On April 26, 1933, the Territorial Legislature enacted a bill placing Hawaii on daylight saving time from the last Sunday in April (April 30 in that year) to the last Sunday in September, but the law was repealed three weeks later on May 21, 1933.[27] During World War II between February 9, 1942 and September 30, 1945, Hawaiian Standard Time was advanced one hour to so-called "Hawaiian War Time," effectively placing the territory on year-round daylight saving time.[28]
Indiana[edit]
See also: Time in Indiana
From 1970 until 2006, most of Indiana in the Eastern Time Zone did not observe daylight saving time, but the entire state started to do so in April 2006 after eight counties in western Indiana were shifted from the Central Time Zone to the Eastern Time Zone.[29] One goal for observing DST was to get more Indiana counties observing the same time zone; formerly, 77 counties observed EST, 5 observed EST/EDT (the EDT usage being unofficial only), and 10 observed CST/CDT. As of 2016[update], Indiana has 12 counties observing Central Daylight Time while the remaining 80 counties observe Eastern Daylight Time. Those counties observing CST are in two groups: one near or in the Chicago metropolitan area, and the other around Evansville in the southwest corner of the state.
Michigan[edit]
In 1967 the Michigan Legislature adopted a statute, Act 6 of the Public Acts of 1967, exempting the state from the observance of DST. The exemption statute was suspended on June 14, 1967, however, when the referendum was invoked. From June 14, 1967 until the last Sunday in October, 1967, Michigan observed DST, and did so in 1968 as well. The exemption statute was submitted to the voters at the General Election held in November 1968, and, in a close vote, the exemption statute was sustained. As a result, Michigan did not observe DST in 1969, 1970, 1971, or 1972. (Radio station CKLW in Windsor, Ontario, just across the river from Detroit, was popular on both sides of the border and would often give both times on the air, e.g. "It's 4:30 in Detroit and 5:30 in Windsor!") In November 1972, an initiative measure, repealing the exemption statute, was approved by the voters. Michigan again observed DST in 1973, and has continued to do so since then.
The vast majority of Michigan is in the Eastern Time Zone. Only the Upper Peninsula counties that border Wisconsin (Gogebic, Iron, Dickinson, and Menominee) are in Central Time.
Nevada[edit]
This section needs to be updated. Please update this article to reflect recent events or newly available information. (November 2017)
In 2015 the Nevada Senate passed Nevada Assembly Joint Resolution 4, which would make it so that Nevada remains on Daylight Saving Time throughout the year. This would mean that Nevada is on the same time as Arizona all year, but would be an hour ahead of California in the winter.[30] The United States Congress must now approve the change.
Washington[edit]
This section needs to be updated. Please update this article to reflect recent events or newly available information. (November 2017)
In 2015, Rep. Elizabeth Scott (R-Monroe) filed a House bill to end DST in Washington, and a companion bill was filed in the Senate.[31] She told a House committee that the semiannual time switches are not only inconvenient but lead to health problems and accidents due to lost sleep.[32] She added that the bill to drop daylight saving time would reduce heart attacks, car wrecks and work accidents found to increase with the sleep-schedule disruptions.[31] A different Senate Bill would petition the federal government for year-round DST.[31]
Other U.S. locations[edit]
All U.S. insular territories with civilian government (American Samoa, Guam, Northern Mariana Islands, Puerto Rico, and the Virgin Islands) lie in the tropics and do not observe DST.
While neighboring Samoa began observing DST in September 2010, the smaller American Samoa cannot legally follow because of the DST observation period mandated by the Uniform Time Act. This period is actually wintertime in this Southern Hemisphere territory.
Time zones[edit]
Many computer operating systems (such as Microsoft Windows, Linux, UNIX, and macOS) and programming languages (such as Java, perl, and most shell languages) allow a local time zone setting in the format of (standard time zone abbreviation)(UTC hour difference)(daylight saving time zone abbreviation). This allows programs and programming languages that must do calculations based on local time to more easily calculate differences between local time and UTC, as well as knowing whether calculations should be changed during daylight saving time. For example, a time zone setting of EST5EDT indicates that local time on the computer is 5 hours behind UTC and should be adjusted for daylight saving time.
Time Zone
Standard Time
Daylight Saving Time
TZ
Atlantic Time Zone AST (UTC-4) ADT (UTC-3) AST4ADT
Eastern Time Zone EST (UTC-5) EDT (UTC-4) EST5EDT
Central Time Zone CST (UTC-6) CDT (UTC-5) CST6CDT
Mountain Time Zone MST (UTC-7) MDT (UTC-6) MST7MDT
Pacific Time Zone PST (UTC-8) PDT (UTC-7) PST8PDT
Alaska Time Zone AKST (UTC-9) AKDT (UTC-8) AKST9AKDT
Hawaii–Aleutian Time Zone HAST (UTC-10) HADT (UTC-9)
Aleutian Islands only HAST10HADT
See also[edit]
General topic
Daylight saving time
Daylight saving time by country
CHU distributes official time in Canada
History of time in the United States includes a list of historical daylight saving dates back to 1918
Official civil time distribution
WWV and WWVH (NIST Shortwave)
WWVB (NIST Longwave)
Quasi-governmental time distribution systems
CDMA cellphone stratum 2 time distribution system
GNSS global navigation stratum 1 time distribution system
References[edit]
Jump up ^ "Most of Exempt from Daylight Saving Time", timeanddate.com. Retrieved February 14, 2013.
Jump up ^ "Daylight Time". United States Naval Observatory. Retrieved October 18, 2012.
Jump up ^ History of Daylight Saving Time, timeanddate.com; accesses 2017.03.05.
Jump up ^ Editors (25 October 1918). "Clocks Change Tomorrow" (PDF). The New York Times Company. The New York Times. Retrieved 1 November 2015.
Jump up ^ 66th U.S. Congress. "CHAP. 51. An Act For the repeal of the daylight-saving law" (pdf). Legis Works. Retrieved November 3, 2013. (Pub.L. 66–40, 41 Stat. 280, enacted August 20, 1919)
Jump up ^ 77th U.S. Congress. "AN ACT To promote the national security and defense by establishing daylight saving time" (pdf). Legis Works. Retrieved November 3, 2013. (Pub.L. 77–403, 56 Stat. 9, enacted January 20, 1942)
^ Jump up to: a b c d e f g h i Source: CRS Report to Congress s:Congressional Research Service Report RS22284 Daylight Saving Time
Jump up ^ 93rd U.S. Congress. "AN ACT To provide for daylight saving time on a year-round basis for a two-year trial period, .." (pdf). United States Government Printing Office. Retrieved 2 November 2013. (Pub.L. 93–182, 87 Stat. 707, enacted December 15, 1973)
Jump up ^ Dunning, Brian. "Skeptoid #172: Daylight Saving Time Myths". Skeptoid. Retrieved June 19, 2017.
Jump up ^ 109th U.S. Congress. "Sec. 110. Daylight Savings" (PDF). An Act To ensure jobs for our future with secure, affordable, and reliable energy. United States Government Printing Office. Retrieved November 3, 2013. (Pub.L. 109–58, 119 Stat. 594, enacted August 8, 2005)
Jump up ^ Douma, Michael (2008). "Daylight Saving Time — When do we change our clocks?". Institute for Dynamic Educational Advancement. Retrieved March 8, 2008.
Jump up ^ "Time and Frequency Division FAQ". National Institute of Standards and Technology.
Jump up ^ Ast, William F. III (October 30, 2009). "Time shifts backward early Sunday morning". The Herald-Palladium. Retrieved October 30, 2009.
Jump up ^ Belzer, David B. (October 2008). "Impact of Extended Daylight Saving Time on National Energy Consumption" (PDF). U.S. Department of Energy. Archived from the original (PDF) on 2013-05-18.
Jump up ^ Lotchen, Matthew (October 2008). "Does Daylight Saving Time Save Energy? Evidence from a Natural Experiment in Indiana" (PDF). National Bureau of Economic Research.
Jump up ^ Moritz, Katie (April 10, 2015). "Clock Stopped on Daylight Saving Time Repeal – For Now". Juneau Empire. Retrieved May 8, 2015.
Jump up ^ Shimoda, Yoshiyuki; Asahi, Takahiro; Taniguchi, Ayako; Mizuno, Minoru (2007). "Evaluation of city-scale impact of residential energy conservation measures using the detailed end-use simulation model". Energy. 32 (9): 1617. doi:10.1016/j.energy.2007.01.007.
Jump up ^ "Navajo Nation". Wwp.greenwichmeantime.com. Retrieved June 25, 2010.
Jump up ^ "Proposition 12: Daylight Saving Time". UC Hastings Scholarship Repository. University of California Hastings. 1949. Retrieved March 23, 2017.
Jump up ^ "California Wants To Ban Daylight Saving Time". The Huffington Post. March 11, 2016. Retrieved March 13, 2016.
Jump up ^ A.B. 807, 2017–2018 Reg. Sess. (Cal. 2017). An act to add Section 6808 to the Government Code, and to repeal Sections 1, 2, 3, 4, and 5 of the Daylight Saving Time Act, an initiative measure approved at the November 8, 1949, special election, relating to daylight saving time.
Jump up ^ Murphy, Katy (March 10, 2017). "California debates daylight saving time — again". San Jose Mercury News. Retrieved March 23, 2017.
Jump up ^ "HB 701 – Daylight Saving Time". Retrieved May 25, 2015.
Jump up ^ Colavecchio-Van Sickler, Shannon (March 27, 2008). "Posey's daylight savings bill moves". Tampa Bay Times.
Jump up ^ "Hawaii Revised Statutes, § 1-31". Capitol.hawaii.gov. Retrieved June 25, 2010.
Jump up ^ "Astronomical Data Applications". U.S. Naval Meteorology & Oceanography Command. Retrieved June 25, 2010.
Jump up ^ Session Laws of Hawaii, 933, enacted by Act 90 (approved April 26, 1933) and repealed by Act 163 (approved May 21, 1933). Cited in Schmitt, Robert; Cox, Doak (1992). "Hawaiian Time". The Hawaiian Journal of History. 26: 220. Archived from the original on November 5, 2013. Retrieved November 4, 2013.
Jump up ^ Schmitt and Cox, p. 221.
Jump up ^ Standard Time Zone Boundary in the State of Indiana (a 139 KB PDF file)
Jump up ^ Chereb, Sandra (May 18, 2015). "Nevada lawmakers urge Congress to allow state to stay on daylight savings time". Las Vegas Review-Journal.
^ Jump up to: a b c "Bill would end daylight saving time in Washington state". The Oregonian. AP. February 3, 2015. Retrieved November 5, 2016.
Jump up ^ Nunnally, Derrick (February 3, 2015). "Lawmakers want to end Daylight Saving Time in Washington". AP. Retrieved November 5, 2016.
External links[edit]
Washington Post: Overview of anti-DST initiatives by states in 2015
Steverman, Ben (March 10, 2017). "Proof daylight saving time is dumb, dangerous, and costly". Boston Globe. Bloomberg News. Retrieved March 10, 2017.
[hide]
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t
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Daylight saving time in the Americas
North America
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Sovereign states
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Argentina
Bahamas
Barbados
Belize
Bolivia
Brazil
Canada
Chile
Colombia
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Dominica
Dominican Republic
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Guyana
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Mexico
Nicaragua
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Saint Kitts and Nevis
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Dependencies and
other territories
Anguilla
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Bonaire
British Virgin Islands
Cayman Islands
Curaçao
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French Guiana
Greenland
Guadeloupe
Martinique
Montserrat
Puerto Rico
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Saba
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Sint Maarten
South Georgia and the South Sandwich Islands
Turks and Caicos Islands
US Virgin Islands
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Koyna Hydroelectric Project
From Wikipedia, the free encyclopedia
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Koyna Dam
Shivasagar lake
The Koyna Hydroelectric Project is the largest completed hydroelectric power plant in India.[1] It is a complex project with four dams including the largest dam on the Koyna River, Maharashtra hence the name Koyna Hydroelectric Project. The project site is in Satara district near Patan.
The Deshmukhwadi village on which koyna dam is situated is migrated on hill station near to Koyna Dam.
The total capacity of the project is 1,960 MW. The project consists of four stages of power generation. All the generators are located in underground powerhouses excavated deep inside the mountains of the Western Ghats. A dam foot powerhouse also contributes to the electricity generation. Due to the project's electricity generating potential the Koyna River is considered as the life line of Maharashtra.
The project takes advantage of the height of Western Ghats. Thus a very large hydraulic head is available over a very short distance.
Contents
1 History
2 Description
2.1 Stage I and II
2.2 Stage III
2.3 Stage IV
3 Features
4 Future plans
5 Tourism
5.1 Koyna Wildlife Sanctuary
5.2 Nehru Memorial park
5.3 Ozarde falls
6 See also
7 References
8 External links
History[edit]
In the early 20th century, there was a survey of the Koyna River as a potential hydro-electric source. After the First World War, a hydro-electric project on the Koyna river was investigated by the Tata Group. The 1928 financial crisis caused the project to be shelved. After the independence of India, it was taken over by the Government of Maharashtra. In 1951 Koyna Dam division started to look into the project. The project was approved in 1953 and work commenced in early 1954.
Description[edit]
Head race tunnel
Head race tunnel
Outdoor switchyard
The project is composed of four dams with the major contributors being the Koyna Dam and Kolkewadi Dam. The water from Shivasagar reservoir was formed by the Koyna Dam and is used in the 1st, 2nd and 4th stages. This water is drawn from head race tunnels situated below the reservoir. Then it travels through vertical pressure shafts to the underground powerhouses. The discharged water from these stages is collected and stored in Kolkewadi Dam situated near village of Alore. The water is drawn from the penstocks of Kolkewadi Dam to an underground power station in the 3rd stage and then discharged to the Arabian Sea.
The electricity generated in all the stages is delivered to the main electrical grid. The project is run by the Maharashtra State Electricity Board.
Stage
Unit number
Installed capacity (MW)
Date of commissioning
Status
Stage I 1 70 1962 May Running [2]
Stage I 2 70 1962 August Running
Stage I 3 70 1963 January Running
Stage I 4 70 1963 February Running
Stage II 5 80 1967 June Running
Stage II 6 80 1966 November Running
Stage II 7 80 1966 June Running
Stage II 8 80 1966 March Running
Stage III 9 80 1975 July Running
Stage III 10 80 1976 January Running
Stage III 11 80 1977 May Running
Stage III 12 80 1977 Running
Stage IV 13 250 1981 Running
Stage IV 14 250 1981 Running
Stage IV 15 250 1981 Running
Stage IV 16 250 1981 Running [3]
Besides this dam foot powerhouse part of power plant also produces 40 MW through two generating units of 20 MW each, totalling 1960 MW. Details of each stage are given below.
Stage I and II[edit]
The first stage of the project was approved in late 1953 and construction began in early 1954. Initially a two-stage construction was conceived. But the total generation capacity of the two stages was too large for load forecasts of that time. So a time lag of more than 10 years was proposed between the two stages. Within two years thereafter, it came to be noticed that the 10 years time tag between these two stages will not be affordable and to cope up with the power requirements, the two stages should be merged and both the stages should be constructed simultaneously. Hence, it was accepted that the two stages have to be executed as one.
The 1st and 2nd stages share same powerhouse with total eight Pelton turbine units. Each of the two stages has four turbines having capacity of 65 MW each for 1st stage and 75 MW each for 2nd stage. The water from Shivasagar reservoir is taken through an intake structure known as Navja tower near village of Navja into the head race tunnel. Then it travels towards the surge tank. It is further divided into four pressure shafts which run vertically downward delivering water to the turbines. Then the water is discharged into the tail race tunnel.
A dam foot powerhouse was also constructed which is used to generate electricity by the water which is discharged from the Koyna Dam for irrigation purpose. It has two Francis turbine units of 20 MW each. This powerhouse is run according to the irrigation requirements of the downstream areas.
The combined installed capacity of the two stages and the dam foot powerhouse is 600 MW.
Stage III[edit]
Initially a weir was proposed to divert the water coming out of tail race tunnel of Stage I and II. But it was later observed that the water still had a hydraulic head of about 120 m which could be used. To use this head, the Kolkewadi Dam was constructed at this location. It forms a balancing reservoir and maintains the head. This dam impounds the tail race water from Stage I and II. This water is drawn through penstocks and electricity is generated by four Francis turbine units with a capacity of 80 MW each. The tail race water from these stages then flows through a channel and joins the Arabian Sea near Chiplun.
The installed generating capacity of this stage is 320 MW.
Stage IV[edit]
Later in the 1980s, the electricity demand of the Maharashtra increased tremendously resulting in inadequate power supply. The Planning Commission accorded approval to Stage IV with installation capacity of 4 × 250 MW. Thus, one more stage called Stage IV was added to power system of Stages I and II, thus converting the Koyna Power Station into a peaking power station complex with load factor of about 18.7%. This scheme also draws water from the existing Shivasagar reservoir same as Stages I and II.
A nonconventional intake system was created by piercing the lake from the bottom by blasting the rock plug using dynamite.[4] This double lake tapping process was the first of its kind in Asia.[5]
The water in head race tunnel is directly drawn from the reservoir and delivered to the head surge tank. Then four pressure shafts take the water downward vertically. The four huge Francis turbine units of 250 MW each generate electricity and tail race water is taken into the Kolkewadi Dam reservoir through tail race tunnel. A revolutionary gas insulated switchgear system is used in the underground powerhouse of this stage.
The installed capacity of this stage alone is 1000 MW. This stage is mostly used to cater for the peak hour demands of the electric grid.
Features[edit]
Stage I & II
Stage III
Stage IV
Dam
Catchment area 891.78 km2 (344 sq mi) 25.04 km2 (10 sq mi) Capacity of stage I & II is utilised
Capacity 2797 MCM 36 MCM
Max. height above foundation 103.02 m 63.30 m
Length 807.72 m 497.00 m
Intake works
Head race tunnel length 3748 m 4551 m 4230 m
Intake tunnel diameter 6.4 m circular 7.4 m D shape 7 m × 9.50 m horseshoe shape
Discharge capacity 164 m3/s 170 m3/s 260 m3/s
Pressure shafts
Number 4 4 4
Length(each) 616 m 192 m 590 m
Power house
Approach tunnel length 864 m 780 m 988 m
Tail race tunnel length 2215 m 4543 m 2314 m
Number of turbines 4 (stage I) + 4 (stage II) + 2 (dam foot powerhouse) = 10 4 4
Type of turbine Pelton (stage I & II) Francis (dam foot powerhouse) Francis Francis
Installed generation capacity 600 MW 320 MW 1000 MW
Switch yard 4572 m 340 m 134 m × 18 m underground
Load factor 60% 24% 18% (1 + 2 & 4)
This is the largest completed hydroelectric project in India.[1]
The water used for generation of electricity joins the Arabian Sea near Chiplun while the water which discharges through the spillways of the dam in monsoon season joins the Bay of Bengal through the Krishna River.
The process of double lake tapping was the first of its kind in Asia.[5]
All the components of the project such as powerhouses, head race and tail race tunnels, pressure shafts are constructed underground.
The modern gas insulated switchgear system is used in 4th stage of the project.
Future plans[edit]
To utilise more water from the Shivasagar reservoir, another dam foot powerhouse is being constructed on the left bank of the dam. This powerhouse will employ a pumped storage scheme. Also lake tapping is proposed for the intake system.
Tourism[edit]
The impounded water of the Koyna Dam though has submerged a significant amount of rain forest of the Western Ghats, it has helped a lot to the surrounding forest by supplying water all round the year. Hence a wide biodiversity of plants and animals is observed in the evergreen forest surrounding the reservoir area.
Koyna Wildlife Sanctuary[edit]
A part of the evergreen forest in surrounding area of the project
Main article: Koyna Wildlife Sanctuary
Koyna Wildlife Sanctuary has dense forests with three major sections, Vasota, Maharkhor and Indavli Met, and the sanctuary is endowed with natural protective boundaries – Shivasagar Lake on one side, and the slopes of the Western Ghats on both the sides. This protective cover has enabled the emergence of a diverse variety of flora and fauna in the sanctuary. Some of the endangered species of trees found in the sanctuary are Dhup (Boswellia serrata), Euphorbia longan, and Elaeocarpus spp., apart from many other species of trees. The sanctuary has a diverse variety of fauna including tigers and panthers; gaurs and sambars; barking and mouse deer; pythons and cobras; common langurs and Indian giant squirrels. Many species of birds are found in the sanctuary including brown capped woodpecker; Asian fairy bluebird; and crested goshawk.
Another attraction of the sanctuary is Vasota Fort which lies deep in the forest and is located at a height of 1,120 m (3,675 ft) above sea level. The legend states that the fort was constructed by Malwa king Raja Bhoja in 1170.
Nehru Memorial park[edit]
When the project work was almost nearing completion, on 10 April 1960, the then Prime Minister of India Pdt. Jawaharlal Nehru visited Koyna Project. To commemorate this event a tablow was unveiled at his gracious hands on the right flank hillock of Koyna Dam. This project came up with an idea of immortalising this place and this event by constructing a beautiful park and naming it as "Nehru Memorial Park". This park is a major attraction for tourists. An upstream side view of dam is visible from this garden. There is an auditorium named 'Yashogatha' (meaning: story of success) which reviles a small element of the tremendous efforts taken by the engineers and workers associated with project. It is one of the most beauty in satara. & success of india.
Ozarde falls[edit]
Ozarda fall
Due to the large rainfall in the hilly region surrounding the reservoir, some beautiful falls are generated in the monsoon season. The largest of them is the Ozarda falls near Navaja village 10 km from Koyna. This is also a major attraction for tourists visiting in monsoon season.
See also[edit]
Maharashtra portal
Water portal
Renewable energy portal
Koyna Dam
Koyna Wildlife Sanctuary
List of power stations in India
List of conventional hydroelectric power stations
References[edit]
^ Jump up to: a b india-reports.com. india-reports.com http://www.india-reports.com/articles/ElectricityInIndia/electricity_india_hydroelectric_largest_powerplant.aspx. Missing or empty |title= (help)
Jump up ^ Infraline Energy Research. "Updated: April 2011 Pophali Hydro Power Station Promoter". Infraline Energy. Retrieved 20 April 2015.
Jump up ^ "Koyna I-IV (Pophali) Hydro Power Plant India - GEO". Retrieved 20 April 2015.
Jump up ^ "Under water lake tapping at Koyna project" (PDF). Retrieved 29 December 2012.
^ Jump up to: a b "Rane triggers lake tapping at Koyna". Retrieved 20 April 2015.
External links[edit]
Wikimedia Commons has media related to Koyna Hydroelectric Project.
Official website
Coordinates: 17°24′06″N 73°45′08″E / 17.40167°N 73.75222°E / 17.40167; 73.75222
Retrieved from "https://en.wikipedia.org/w/index.php?title=Koyna_Hydroelectric_Project&oldid=791429021"
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text:
Windows Runtime
From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
"WinRT" redirects here. It is not to be confused with Windows RT.
Windows Runtime
A component of Microsoft Windows
Details
Other names
WinRT
Type
Application programming interface
Included with
Windows Server 2012, Windows 8, Windows RT, Windows 8.1, Windows Phone 8.1, Windows Server 2012 R2, Windows 10, Windows 10 Mobile, Windows Server 2016
Related components
Windows Store, Windows API
Windows Runtime (WinRT) is a platform-agnostic application architecture first introduced in Windows 8 and Windows Server 2012 in 2012. WinRT supports development in C++/CX (Component Extensions, a language based on C++), JavaScript-TypeScript, and the managed code languages C# and Visual Basic .NET (VB.NET). WinRT applications natively support both the x86 and ARM processors, and run inside a sandboxed environment to allow greater security and stability.[1][2] WinRT components are designed with interoperability between multiple languages and APIs in mind, including native, managed and scripting languages.
Windows Phone 8.1 uses a version of the Windows Runtime named the Windows Phone Runtime. It enables developing applications in C# and VB.NET, and Windows Runtime components in C++/CX.[3]
Contents
[hide]
1 Technology
2 Services
2.1 Metadata
2.2 Type system
2.2.1 WinRT components
2.3 Programming interfaces
2.3.1 C++ (C++/WinRT, Component Extensions, WRL)
2.3.2 .NET
2.3.3 JavaScript
2.3.4 Bridges
2.4 API
2.4.1 Runtime classes
2.4.2 Naming conventions
2.4.3 Restrictions and rules
3 Version history
4 Windows Phone Runtime
4.1 Windows Phone 8
4.2 Windows Phone 8.1
5 See also
6 References
7 External links
Technology[edit]
WinRT is implemented in the programming language C++[4] and is object-oriented by design.[4] Its predecessor, Windows API (Win32 API) is written mostly in the language C.[5] It is an unmanaged code application programming interface (API) based on Component Object Model (COM) that allows interfacing from multiple languages, as does COM. However, the API definitions are stored in .winmd files, which are encoded in ECMA 335 metadata format, which .NET Framework also uses with a few modifications.[6][unreliable source?] This common metadata format allows significantly less overhead when invoking WinRT from .NET applications, relative to P/Invoke, and much simpler syntax.[7][unreliable source?]
The new C++/CX (Component Extensions) language, which borrows some C++/CLI syntax, allows writing and consuming WinRT components with less glue code visible to the programmer, relative to classic COM programming in C++, and imposes fewer restrictions relative to C++/CLI on mixing types. The Component Extensions of C++/CX are recommended for use at the API-boundary only, not for other purposes.[8] Regular C++ (with COM-specific discipline) can also be used to program with WinRT components,[9] with the help of the Windows Runtime C++ Template Library (WRL), which is similar in purpose to what Active Template Library provides for COM.[10]
WinRT applications run within a sandbox and need explicit user approval to access critical OS features and underlying hardware. File access is restricted to several predetermined locations, such as the directories Documents or Pictures.
WinRT applications for Windows RT, Windows 8 and beyond are packaged in the .appx file format; based upon Open Packaging Conventions, it uses a ZIP format with added XML files.[11] WinRT applications are distributed mostly through an application store named Windows Store, where WinRT software (termed Windows Store apps) can be downloaded and purchased by users. WinRT apps can only be sideloaded from outside Windows Store on Windows 8 or RT systems that are part of a Windows domain, or equipped with a special activation key obtained from Microsoft.[12][13][14][15]
In a major departure from Win32 and similarly to .NET Framework 4.5, most APIs which are expected to take significant time to complete are implemented as asynchronous. The application dispatches the API call, which returns immediately, freeing the application to perform other tasks while waiting for results.[16] The asynchronous model requires new programming language constructs (keyword async and operator await in C# and Visual Basic, class task and method .then in C++, which are provided by the WinRT software development kit (SDK), keyword promise and function then in JavaScript-HTML5), similar to try/catch used in exception handling. Parts of the API needing asynchronous access include on-screen messages and dialogs, file access, Internet connectivity, sockets, streams, devices and services, and calendar, contacts and appointments.
Services[edit]
Metadata[edit]
See also: Metadata (CLI)
The metadata describes the code written for the WinRT platform. It defines a programming model that makes it possible to write object-oriented code that can be shared across programming languages, and enables services like reflection.
Herb Sutter, C++ expert at Microsoft, explained during his session on C++ at the 2011 Build conference that the WinRT metadata is CLI metadata.[8] Native code (i.e., processor-specific machine code) cannot contain metadata and it is then stored in separate WINMD-files that can be reflected like ordinary CLI assemblies.[17]
Because it is CLI metadata, code written in native WinRT languages can be used from managed CLI languages.
Type system[edit]
WinRT has a rich object-oriented class-based type system that is built on the metadata. It supports constructs with corresponding constructs in the .NET framework: classes, methods, properties, delegates, and events.
One of the major additions to WinRT relative to COM is the cross-application binary interface (ABI), .NET-style generics. In C++/CX these are declared using the keyword generic with a syntax very similar to that of keyword template. WinRT classes (ref classes) can also be genericized using C++ templates, but only template instantiations can be exported to .winmd metadata (with some name mangling), unlike WinRT generics which preserve their genericity in the metadata. WinRT also provides a library of generic containers that parallel those in the C++ Standard Library, and some reciprocal (back-and-forth) conversion functions. The consumption of WinRT collections in .NET languages (e.g., C# and VB) and in JavaScript is more transparent than in C++, with automated mappings into their natural equivalents occurring behind the scenes. When authoring a WinRT component in a managed language, some extra, COM-style rules must be followed, e.g. .NET framework collection types cannot be declared as return types, but only the WinRT interfaces that they implement can be used at the component boundary.
WinRT components[edit]
Classes that are compiled to target the WinRT are called WinRT components. They are classes that can be written in any supported language and for any supported platform. The key is the metadata. This metadata makes it possible to interface with the component from any other WinRT language. The runtime requires WinRT components that are built with .NET Framework to use the defined interface types or .NET type interfaces, which automatically map to the first named. Inheritance is as yet not supported in managed WinRT components, except for XAML classes.[18]
Programming interfaces[edit]
Programs and libraries targeted for the WinRT runtime can be created and consumed from several platforms and programming languages. Notably C/C++ (either with language extensions offering first-class support for WinRT concepts, or with a lower-level template library allowing to write code in standard C++), .NET (C# and Visual Basic .NET (VB.NET)) and JavaScript. This is made possible by the metadata.
In WinRT terminology, a language binding is termed a language projection.
C++ (C++/WinRT, Component Extensions, WRL)[edit]
See also: C++/CX
Native C++ is a first-class citizen of the WinRT platform. As of version 10.0.17134.0 (Windows 10, version 1803), the Windows SDK contains C++/WinRT. C++/WinRT is an entirely standard modern C++17 language projection for Windows Runtime (WinRT) APIs, implemented as a header-file-based library, and designed to provide first-class access to the modern Windows API. With C++/WinRT, Windows Runtime APIs can be authored and consumed using any standards-compliant C++17 compiler. WinRT is a native platform and supports any native (and standard) C++ code, so that a C++ developer can reuse existing native C/C++ libraries. With C++/WinRT, there are no language extensions.
Prior to C++/WinRT being officially released in the Windows SDK, from October 2016,[19] Microsoft offered on GitHub C++/WinRT.[20] It does not rely on C++/CX code, with the result of producing smaller binaries and faster code.[21]
There are two other legacy options for using WinRT from C++: WRL, an ATL-style template library, and C++/CX (C++ with Component Extensions) which resembles C++/CLI.[22] Because of the internal consumption requirements at Microsoft, WRL is exception-free, meaning its return-value discipline is HRESULT-based just like that of COM.[23] C++/CX on the other hand wraps-up calls to WinRT with code that does error checking and throws exceptions as appropriate.[24]
C++/CX has several extensions that enable integration with the platform and its type system. The syntax resembles the one of C++/CLI although it produces native (although not standard) code and metadata that integrates with the runtime. For example, WinRT objects may be allocated with ref new, which is the counterpart of gcnew from C++/CLI. The hat operator ^ retains its meaning, however in the case where both the caller and callee are written in C++ and living in the same process, a hat reference is simply a pointer to a vptr to a virtual method table (vtable, VMT).[24]
Along with C++/CX, relative to traditional C++ COM programming, are partial classes, again inspired by .NET. These allow instance XAML code to be translated into C++ code by tools, and then combined with human-written code to produce the complete class while allowing clean separation of the machine-generated and human-edited parts of a class implementation into different files.
.NET[edit]
See also: .NET Framework
The .NET Framework and the Common Language Runtime (CLR) are integrated into the WinRT as a subplatform. It has influenced and set the standards for the ecosystem through the metadata format and libraries. The CLR provides services like JIT-compilation code and garbage collection. WinRT applications using .NET languages use the new Windows Runtime XAML Framework, and are primarily written in C#, VB.NET, and for the first time for XAML, with native code using C++/CX. Although not yet officially supported, programs can also be written in other .NET languages.
Limits
Classes defined in WinRT components that are built in managed .NET languages must be declared as sealed, so they cannot be derived from. However, non-sealed WinRT classes defined elsewhere can be inherited from in .NET, their virtual methods overridden, and so on; but the inherited managed class must still be sealed.
Members that interface with another language must have a signature with WinRT types or a managed type that is convertible to these.[18]
JavaScript[edit]
See also: JavaScript, Rich Internet Application, and WinJS
WinRT applications can also be coded using HTML with JavaScript in code-behind, which are run using the Trident rendering engine and Chakra JavaScript engine, both of which are also used by Internet Explorer. When coding a WinRT app in JavaScript, its features are adapted to follow JavaScript naming conventions, and namespaces are also mapped to JavaScript objects.
Bridges[edit]
This section needs expansion. You can help by adding to it. (August 2015)
API[edit]
WinRT comes with an application programming interface (API) in the form of a class library that exposes the features of Windows 8 for the developer, like its immersive interface API. It is accessible and consumable from any supported language.
Runtime classes[edit]
The Windows Runtime classes is a set SDKs that provide access to all functionality from the XAML parser to the camera function. The SDKs are implemented as native C/C++ libraries (unmanaged).
Naming conventions[edit]
The naming conventions for the components (classes and other members) in the API are heavily influenced by the .NET naming conventions which uses camel case (specifically PascalCase). Microsoft recommends users to follow these rules in case where no others are given.
These conventions are projected differently in some languages, like JavaScript, which converts it to its conventions and the other way around. This is to give a native and consistent experience regardless of the programming language.
Restrictions and rules[edit]
Since Windows Runtime is projected to various languages, some restrictions on fundamental data types exist so as to host all such languages. Programmers must be careful with the behavior of those types when used with public access (for method parameters, method return values, properties, etc.).[25]
Basic types
In .NET languages and C++, a rich set of data types exists, representing various numerals.
In JavaScript, a Number can only represent up to 53 bits of precision.
In WinRT, the only lacking numeral data type is 8-bit signed integer relative to .NET and C++. JavaScript developers must be careful when dealing with big numbers while coding for WinRT.
Strings
Strings are immutable in .NET and JavaScript, but mutable in C++.
A null pointer passed as a string to WinRT by C++ is converted to an empty string
In .Net, null being passed as a string to WinRT is converted to an empty string
In JavaScript, null being passed as a string to WinRT is converted to a string with the word null. This is due to JavaScript's keyword null being represented as a null object
Similar results occur when passing undefined to WinRT from JavaScript
Structs
In .NET and C++, structs are value types, and such a struct can contain any type in it.
JavaScript does not directly support structs.
In WinRT, use of structs is allowed only for containing types that have value semantics, including numerals, strings, and other structs. Pointers or interface references are disallowed.
References
In .NET, objects are passed by reference, whereas numerals and structs are passed by value.
In C++, all types can be passed by reference or value.
In WinRT, interfaces are passed by reference; all other types are passed by value.
Arrays
In .NET, C++, and JavaScript arrays are reference types.
In WinRT, arrays are value types.
Events
In .NET and C++, clients subscribe to events using += operator.
In JavaScript, addEventListener function or setting on<EventName> property is used to subscribe to events.
In WinRT, all languages can use their own way to subscribe to events.
Collections
Some .NET collections map directly to WinRT collections.
WinRT Vector type resembles arrays and the array syntax is used to consume them.
WinRT Map type is a key/value pair collection, and is projected as Dictionary in .NET languages.
Method overloading
All WinRT languages (.NET, C++, JavaScript) support overloading on parameters
.NET and C++ also support overloading on type.
In WinRT, only parameter number is used for overloading.
Asynchrony
All WinRT methods are designed such that any method taking longer than 50 milliseconds is an async method.
The established naming pattern to distinguish asynchronous methods is <Verb>[<Noun>]Async. For the full runtime library, all methods that have a chance to last longer than 50 ms are implemented as asynchronous methods only.
Version history[edit]
This section needs expansion. You can help by adding to it. (August 2015)
Windows version
Windows 8 Windows Runtime
Windows 8.1
Windows 10 Universal Windows Platform (UWP)
Windows Phone Runtime[edit]
Starting from Windows Phone 8 it is possible to develop apps using a version of the Windows Runtime called the Windows Phone Runtime (WPRT). Although WP8 brought limited support, the platform did eventually converge with Windows 8.1 in Windows Phone 8.1.
Windows Phone 8[edit]
Windows Phone 8 has limited support for developing and consuming Windows Runtime components through Windows Phone Runtime. Many of the Windows Runtime APIs in Windows 8 that handle core operating system functions have been ported to Windows Phone 8.[26] Support for developing native games using C++/CX and DirectX has been added, by request from the game development industry.
However, the Windows Phone XAML Framework is still based on the same Microsoft Silverlight framework, as in Windows Phone 7, for backward compatibility. Thus, as of 2016[update], XAML development is impossible in C++/CX. Development using either HTML5 or WinJS is unsupported on Windows Phone 8.
Windows Phone 8.1[edit]
Windows Runtime support on Windows Phone 8.1 converges with Windows 8.1. The release brings a full Windows Runtime API to the platform, including support for Windows Runtime XAML Framework, and language bindings for C++/CX, and HTML5-JavaScript. There is also a project type called Universal apps to enable apps to share code across 8.1 versions of Windows Phone and Windows.
The Windows Phone 8 Silverlight Framework has been updated.[when?] It can exploit some of the new features in the Windows Runtime.
Windows Phone Runtime uses the AppX package format from Windows 8, after formerly using Silverlight XAP.
See also[edit]
Windows Runtime XAML Framework
References[edit]
Jump up ^ Avram, Abel (21 September 2011). "Design Details of the Windows Runtime". InfoQ.
Jump up ^ Klug, Brian; Smith, Ryan (13 September 2011). "Microsoft Build: Windows 8, A Pre-Beta Preview". AnandTech.
Jump up ^ "Windows Phone API reference". Windows Phone API reference. Microsoft. July 21, 2014.
^ Jump up to: a b Michael, Mayberry (2012). WinRT Revealed. New York City: Apress. p. 3. ISBN 978-1-4302-4585-8.
Jump up ^ "Creating Win32 Applications (C++)". MSDN. Microsoft. Retrieved 12 January 2014.
Jump up ^ De Icaza, Miguel (15 September 2011). "WinRT demystified". Personal blog of Miguel de Icaza. Self-published. Retrieved 15 January 2014.
Jump up ^ "What is the COM marshaling overhead in calling the WinRT API from C#?". MSDN forum. Self-published. 20 September 2011. Retrieved 15 January 2014.
^ Jump up to: a b "Using the Windows Runtime from C++ | Build2011 | Channel 9". Channel9.msdn.com. 2011-09-14. Retrieved 2012-04-24.
Jump up ^ Sivakumar, Nish (2011-09-29). "Visual C++ and WinRT/Metro - Some fundamentals - CodeProject®". Codeproject.com. Retrieved 2012-04-24.
Jump up ^ "Using the Windows Runtime from C++ | Build2011 | Channel 9". Channel9.msdn.com. 2011-09-14. Retrieved 2012-04-24.
Jump up ^ "Designing a simple and secure app package – APPX". Windows 8 app developer blog. Retrieved 30 December 2013.
Jump up ^ "How to Add and Remove Apps". TechNet. Microsoft. 31 May 2012. Retrieved 4 October 2012. To enable sideloading on a Windows 8 Enterprise computer that is not domain-joined or on any Windows® 8 Pro computer, you must use a sideloading product activation key. To enable sideloading on a Windows® RT device, you must use a sideloading product activation key. For more information about sideloading product activation keys, see Microsoft Volume Licensing.
Jump up ^ "Windows 8: The Metro Mess". PC Magazine. Retrieved 8 September 2012.
Jump up ^ "Microsoft now using 'Modern UI Style' to refer to Windows 8 'Metro Style' apps". Retrieved 10 August 2012.
Jump up ^ "What's a Windows Store app?". Windows Dev Center. Retrieved 1 October 2012.
Jump up ^ "Asynchronous programming (Windows Store apps)". MSDN. Microsoft. Retrieved 12 January 2014.
Jump up ^ ".NET Gets a New Lease of Life". Archived from the original on September 24, 2011. Retrieved September 16, 2011.
^ Jump up to: a b "Using the Windows Runtime from C# and Visual Basic | Build2011 | Channel 9". Channel9.msdn.com. 2011-09-14. Retrieved 2012-04-24.
Jump up ^ "Initial preview release of C++/WinRT". github.com. 2016-10-05. Retrieved 2016-10-05.
Jump up ^ "C++/WinRT is a standard C++ language projection for the Windows Runtime". github.com. 2016-09-14. Retrieved 2016-09-14.
Jump up ^ "Standard C++ and the Windows Runtime (C++/WinRT)". blogs.windows.com. 2016-11-28. Retrieved 2016-11-28.
Jump up ^ "Inside the C++/CX Design - Visual C++ Team Blog - Site Home - MSDN Blogs". Blogs.msdn.com. 2011-10-20. Retrieved 2012-04-24.
Jump up ^ Charles (2011-10-26). "GoingNative 3: The C++/CX Episode with Marian Luparu | C9::GoingNative | Channel 9". Channel9.msdn.com. Retrieved 2012-04-24.
^ Jump up to: a b Under the covers with C++ for Metro style apps with Deon Brewis at //Build
Jump up ^ "Ten Tips When Writing a Hybrid Language Metro style Application - Build2011 - Channel 9". Channel 9. Microsoft.
Jump up ^ "Windows Phone Runtime API". microsoft.com. Microsoft.
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Cabinet of Malawi
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Peter Mutharika
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The Cabinet of Malawi is the executive branch of the government, made up of the President, Vice President, Ministers and Deputy Ministers responsible for the different departments.[1]
Current Cabinet[edit]
Party key
Democratic Progressive Party
United Democratic Front
Cabinet of Malawi: June 2014 – Present[2]
Portrait
Portfolio
Incumbent
Term began
President
Minister of Defence
Commander-in-chief of the Armed and Police forces H.E. Peter Mutharika 31 May 2014 –
Vice President
Minister for Civil Service Rt. Hon. Saulos Chilima 31 May 2014 –
Minister of Agriculture and Irrigation Hon. Allan Chiyembekeza MP 19 June 2014 –
Minister of Education, Science and Technology Hon. Emmanuel Fabiano MP 19 June 2014 –
Minister of Finance, Economic Planning and Development Hon. Goodall Gondwe 06 June 2014 –
Minister of Foreign Affairs and International cooperation Hon. George Chaponda MP 19 June 2014 –
Minister of Gender, Children, Disability and Social Welfare Hon. Patricia Kaliati MP 23 June 2014 –
Minister of Health Hon. Peter Kumpalume MP 19 June 2014 –
Minister of Home Affairs Hon. Paul Chibingu MP 23 June 2014 –
Minister of Information, Tourism and Civic Education Hon. Kondwani Nankhumwa MP 19 June 2014 –
Minister of Justice and Constitutional Affairs Hon. Samuel Tembenu 19 June 2014 –
Minister of Labour Hon. Henry Mussa MP 19 June 2014 –
Minister of Lands, Housing and Urban Development Hon. Bright Msaka 23 June 2014 –
Minister of Local Government and Rural Development Hon. Trasizio Gowelo MP 23 June 2014 –
Minister of Natural Resources, Energy and Mining Hon. Atupele Muluzi MP 23 June 2014 –
Minister of Trade and Industry Hon. Joseph Mwanamveka MP 23 June 2014 –
Minister of Transport and Public works Hon. Francis Kasaila MP 19 June 2014 –
Minister of Youth, Sports and Culture Hon. Grace Chiumia MP 19 June 2014 –
Deputy Ministers
Deputy Minister of Defence Hon. Jappie Mhango MP 23 June 2014 –
Deputy Minister of Education Science and Technology Hon. Vincent Ghambi MP 23 June 2014 –
See also[edit]
Malawian past cabinets
References[edit]
Jump up ^ "Malawi president dissolves entire cabinet". Aug 20, 2011. Retrieved 2011-09-14.
Jump up ^ "Malawians give Mutharika Cabinet size thumps up". orakonews.com. Retrieved 25 June 2014.
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Retrieved from "https://en.wikipedia.org/w/index.php?title=Cabinet_of_Malawi&oldid=781154438"
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Cabinet of Malawi
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This page was last edited on 19 May 2017, at 12:31.
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Cabinet of Somaliland

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