Alpha–beta pruning: Difference between revisions

From formulasearchengine
Jump to navigation Jump to search
en>Monkbot
 
→‎Pseudocode: used to be like that and was changed for some reason check out http://stackoverflow.com/questions/12990912/alpha-beta-pruning-algorithm
Line 1: Line 1:
{{multiple issues|
Promoting property can be quite a daunting job, specifically in the current market place environment. Many individuals consider they will need to acquire massive reductions in the importance to be able to market. But, that is certainly not always true. Browse the ideas in this post to further improve your odds of accomplishment!<br><br>In case your house has been on the market for a while, include a new picture of your house that exhibits the actual year and climate. An more aged photograph will make it clear that the property has become listed for quite a while, producing consumers prone to put in the lowest supply.<br><br>When promoting your house, have a real estate appraisal completed before you decide to talk to a real estate professional. An appraiser uses several of the exact same information and facts that a realtor does, but is undoubtedly an impartial assessor of value. An appraiser can give you an acceptable concept of what you could count on for your home, as well as reveal to you evidence of her or his findings.<br><br>Number of architectural capabilities time a property a lot more than popcorn ceilings so eliminating them would be a great home remodeling for individuals planning to promote their residence. The task need to consider no longer when compared to a saturday and sunday as soon as full you should have a ceiling that is certainly much easier to color and maintenance, along with a residence with an interior that won't turn aside potential customers.<br><br>When improving a property to offer, concentrate on obvious improvements first. Upgrading the furnace or setting up warmed up flooring surfaces will be all well and good, however, if the roof top spills consumers will be turned away. You will have a much better probability of getting a profit on your own investment through making sure the outside exterior siding or indoor painting seems very good very first.<br><br>If you are selling your house you need to be specifically cautious about the way you selling price your home. You need to find out the cost of the most expensive and cheapest homes in your neighborhood and stay a place in between. Should you price your home excessive and want to keep lowering the value it will give a alert sign to potential buyers.<br><br>One particular tip to remember in terms of offering your [https://Www.facebook.com/deangraziosipage real estate sells]-estate, is you need to be aware of the existing problem of the marketplace and make sure that you change your house cost consequently. This will help to actually have the ability to easily and reasonably sell your property in the tough industry.<br><br>In case you are promoting a condo, check with your connection about the policies about lock cases. If the condo does not permit lock cases, try and  [https://www.facebook.com/photo.php?v=10152672907502074 Dean Graziosi Visit The Website] shape some thing by helping cover their your real estate professional making it as effortless for that potential shopper as possible. You would like to make a beneficial effect not only along with your condominium although the organization they might need to deal with. So try out making it as convenient as you possibly can.<br><br>Including perks inside your supply can sometimes help a home to sell speedier. Offer you to add the blinds or even a new washing machine and dryer. Display a motivation to spend some shutting down charges or have at home warrantee. Such advantages may be attractive to a customer and will make you stick out versus the competition.<br><br>When thinking about the addition of an area to your house, employ current room and conserve huge. It is rather costly to add more base to your property or lengthen the roof to accommodate another area, along with the excess labor. Think about the possibilities of remodeling the attic room or concluding the basements to provide space and benefit to your residence.<br><br>These tips have already been designed to help you with real-estate marketing attempts. They should be an excellent asset to anybody who is selling any type of whole lot or residence. Although the industry is at present within a slump, that doesn't suggest your costs need to be too.
{{more footnotes|date=March 2011}}
{{lead too short|date=March 2011}}
}}
[[File:US Navy 040924-N-6213R-038 Intelligence Specialist 2nd Class Damon Jenkins of Los Angeles, Calif., reviews aerial reconnaissance imagery on a light table in the Carrier Intelligence Center (CVIC) .jpg|thumb|Aerial reconnaissance imagery being analysed.]]
'''Imagery intelligence''' ('''IMINT'''), is an [[list of intelligence gathering disciplines|intelligence gathering discipline]] which collects information via satellite and [[aerial photography]]. As a means of collecting intelligence, IMINT is a subset of [[intelligence collection management]], which, in turn, is a subset of [[intelligence cycle management]]. IMINT is especially complemented by non-imaging [[MASINT]] electro-optical and radar sensors.
 
==History==
===Origins===
{{main|aerial reconnaissance}}
[[File:Lockheed 12A G-AGTL Ringway 14.04.58 edited-2.jpg|thumb|[[Sidney Cotton]]'s [[Lockheed 12]]A, in which he made a high-speed reconnaissance flight in 1940.]]
Although [[aerial photography]] was first used extensively in the [[First World War]], it was only in the [[Second World War]] that specialized imagery intelligence operations were initiated. High quality images were made possible with a series of innovations in the decade leading up to the war. In 1928, the [[RAF]] developed an electric heating system for the aerial camera. This allowed reconnaissance aircraft to take pictures from very high altitudes without the camera parts freezing.<ref>{{cite web|url=http://web.mit.edu/6.933/www/Fall2000/edgerton/www/pre-hee.html#aerial|title=Photography Before Edgerton}}</ref>
 
In 1939 [[Sidney Cotton]] and [[Flying Officer]] [[Maurice Longbottom (RAF officer)|Maurice Longbottom]] of the [[Royal Air Force|RAF]] suggested that airborne reconnaissance may be a task better suited to fast, small aircraft which would use their speed and high service ceiling to avoid detection and interception. They proposed the use of [[Supermarine Spitfire|Spitfires]] with their armament and [[radio]]s removed and replaced with extra fuel and cameras. This led to the development of the [[Supermarine Spitfire (early Merlin powered variants)#PR Mk I - Early Reconnaissance Versions|Spitfire PR]] variants. These planes had a maximum speed of 396 mph<ref>{{cite book|title=Spies in the Sky |first=Taylor |last=Downing |isbn=9781408702802 |year=2011 |publisher=Little Brown Hardbacks (A & C) |pages=42}}</ref> at 30,000 feet with their armaments removed, and were used for photo-reconnaissance missions. The aircraft were fitted with five cameras which were heated to ensure good results.<ref>{{cite book|author=Cotton, Sidney|title=Aviator Extraordinary: The Sidney Cotton Story|publisher=Chatto & Windus|year=1969|page=169|ISBN=0-7011-1334-0|url=http://books.google.co.uk/books/about/Aviator_extraordinary.html?id=TUHbAAAAMAAJ&redir_esc=y}}</ref>
 
[[Image:Danesfield house 2005.jpg|200px|thumb|left|[[RAF Medmenham]], where aerial reconnaissance intelligence was analysed.]]
The systematic collection and interpretation of the huge amounts of aerial reconnaissance intelligence data soon became imperative. Beginning in 1941, [[RAF Medmenham]] was the main interpretation centre for photographic reconnaissance operations in the [[European theatre of World War II|European]] and [[Mediterranean and Middle East theatre of World War II|Mediterranean]] theatres.<ref>{{cite book|title=Spies in the Sky |first=Taylor |last=Downing |isbn=9781408702802 |year=2011 |publisher=Little Brown Hardbacks (A & C) |pages=80-81}}</ref><ref name=buckscc>[https://ubp.buckscc.gov.uk/SingleResult.aspx?uid='TBC563' Unlocking Buckinghamshire's Past]</ref> The ''[[Central Interpretation Unit]]'' (CIU) was later amalgamated with the Bomber Command Damage Assessment Section and the Night Photographic Interpretation Section of No 3 Photographic Reconnaissance Unit, [[RAF Oakington]], in 1942.<ref name=rcahms>[http://aerial.rcahms.gov.uk/isadg/isadg.php?refNo=GB_551_NCAP/17 Allied Central Interpretation Unit (ACIU)]</ref>
 
During 1942 and 1943, the CIU gradually expanded and was involved in the planning stages of practically every operation of the war, and in every aspect of intelligence. In 1945, daily intake of material averaged 25,000 negatives and 60,000 prints. Thirty-six million prints were made during the war. By [[VE-day]], the print library, which documented and stored worldwide cover, held 5,000,000 prints from which 40,000 reports had been produced.<ref name=rcahms/>
 
American personnel had for some time formed an increasing part of the CIU and on 1 May 1944 this was finally recognised by changing the title of the unit to the ''Allied Central Interpretation Unit'' (ACIU).<ref name=rcahms/> There were then over 1,700 personnel on the unit's strength. A large number of photographic interpreters were recruited from the [[Cinema of the United States|Hollywood Film Studios]] including [[Xavier Atencio]]. Two renowned archaeologists also worked there as interpreters: [[Dorothy Garrod]], the first woman to hold an Oxbridge Chair, and [[Glyn Daniel]], who went on to gain popular acclaim as the host of the television game show ''[[Animal, Vegetable or Mineral?]]''.<ref name=Crossbow/>
 
[[File:Peenemunde test stand VII.jpg|right|thumb|Aerial photograph of the missile [[Test Stand VII]] at [[Peenemünde]].]]
[[Sidney Cotton]]'s aerial photographs were far ahead of their time. Together with other members of his reconnaissance squadron, he pioneered the technique of high-altitude, high-speed photography that was instrumental in revealing the locations of many crucial military and intelligence targets. Cotton also worked on ideas such as a prototype specialist reconnaissance aircraft and further refinements of photographic equipment. At its peak, British reconnaissance flights yielded 50,000 images per day to interpret.
 
Of particular significance in the success of the work of Medmenham was the use of [[stereoscopic]] images, using a between plate overlap of exactly 60%. Despite initial scepticism about the possibility of the German rocket technology, major operations, including the 1943 offensives against the [[V-2]] rocket development plant at [[Peenemünde]], where made possible by painstaking work carried out at Medmenham. Later offensives were also made against potential launch sites at [[Wizernes]] and 96 other launch sites in northern France.
 
It is claimed that Medmanham's greatest operational success was "[[Operation Crossbow]]" which, from 23 December 1943, destroyed the [[V-1 (flying bomb)|V-1]] infrastructure in northern France.<ref name=Crossbow>[http://www.bbc.co.uk/programmes/b011cr8f "Operation Crossbow", BBC2, broadcast 15 May 2011]</ref> According to [[Reginald Victor Jones|R.V. Jones]], photographs were used to establish the size and the characteristic launching mechanisms for both the [[V-1 flying bomb]] and the [[V-2 rocket]].
 
===Post war spyplanes===
[[File:U-2 photo during Cuban Missile Crisis.jpg|thumb|left|Soviet truck convoy deploying missiles near San Cristobal, Cuba, on Oct. 14, 1962 (taken by a [[Lockheed U-2|U-2]])]]
Immediately after World War II, long range aerial reconnaissance was taken up by adapted jet bombers – such as the [[English Electric Canberra]], and its American development, the [[Martin B-57]] – capable of flying higher or faster than the enemy.
 
Highly specialized and secretive strategic reconnaissance aircraft, or spy planes, such as the [[Lockheed U-2]] and its successor, the [[SR-71 Blackbird]] were developed by the [[United States]]. Flying these aircraft became an exceptionally demanding task, as much because of the aircraft's extreme speed and altitude as it was because of the risk of being captured as [[spy|spies]]. As a result, the crews of these aircraft were invariably specially selected and trained.
 
There are claims that the US constructed a [[hypersonic]] reconnaissance aircraft, dubbed the [[SR-91 Aurora|Aurora]], in the late 1980s to replace the Blackbird. Since the early 1960s, in the United States aerial and satellite reconnaissance has been coordinated by the [[National Reconnaissance Office]].
 
===Use of satellites===
[[File:Iraq-030205-powell-un-slide-15.jpg|thumb|right|Serum and Vaccine Institute in [[Al-A'amiriya]], Iraq, as imaged by a US reconnaissance satellite in November 2002.]]
Early photographic reconnaissance satellites used photographic film, which was exposed on-orbit and returned to earth for developing.  These satellites remained in orbit for days, weeks, or months before ejecting their film-return vehicles, called "buckets." Between 1959 and 1984 the U.S. launched around 200 such satellites under the codenames [[CORONA]] and [[KH-7 Gambit|GAMBIT]], with ultimate photographic resolution (ground-resolution distance) better than {{convert|4|in|m}}.<ref name="NRO_GAMBITStory">{{cite web|url=http://www.nro.gov/history/csnr/gambhex/index.html|title=The GAMBIT Story, Appendix A, page 154, initial Sept. 2011 release|publisher=National Reconnaissance Office|date=June 1991}}</ref> The first successful mission concluded on 1960-08-19 with the [[mid-air recovery]] by a [[C-119]] of film from the Corona mission code-named [[Discoverer 14]]. This was the first successful recovery of film from an orbiting satellite and the first aerial recovery of an object returning from Earth orbit.<ref>{{cite web |url=http://nssdc.gsfc.nasa.gov/nmc/spacecraftDisplay.do?id=1960-010A |title=Discoverer 14 - NSSDC ID: 1960-010A |publisher=NASA}}</ref> Because of a tradeoff between area covered and ground resolution, not all reconnaissance satellites have been designed for high resolution; the [[KH-5]]-ARGON program had a ground resolution of 140 meters and was intended for [[cartography|mapmaking]].
 
Between 1961 and 1994 the USSR launched perhaps 500 [[Zenit spy satellite|Zenit]] film-return satellites, which returned both the film and the camera to earth in a pressurized capsule.
 
The U.S. [[KH-11]] series of satellites, first launched in 1976, was made by [[Lockheed Corporation|Lockheed]], the same contractor who built the [[Hubble Space Telescope]]. HST has a 2.4 metre telescope mirror and is believed to have had a similar appearance to the KH-11 satellites. These satellites used [[charge-coupled devices]], predecessors to modern digital cameras, rather than film. Russian reconnaissance satellites with comparable capabilities are named [[Resurs DK]] and [[Persona (satellite)|Persona]].
 
==Aircraft==
Low- and high-flying planes have been used all through the last century to gather intelligence about the enemy. U.S. high-flying reconnaissance planes include the [[Lockheed U-2]], and the much faster [[SR-71 Blackbird]], (retired in 1998). Planes have the advantage over satellites that they can usually produce more detailed photographs and can be placed over the target more quickly, more often, and more cheaply, but have the disadvantage of possibly being intercepted by aircraft or missiles such as in the [[1960 U-2 incident]].
 
[[Unmanned aerial vehicle]]s have been developed for imagery and signals intelligence. These drones are a [[force multiplier]] by giving the battlefield commander an "eye in the sky" without risking a [[aviator|pilot]]. The [[United States Army|US Army]] is significantly increasing the size of its current UAV force as part of the [[Future Combat System]] initiative.
 
==Satellite==
Though the resolution of satellite photographs, which must be taken from distances of hundreds of kilometers, is usually poorer than photographs taken by [[aerial photography|air]], satellites offer the possibility of coverage for much of the earth, including hostile territory, without exposing human pilots to the risk of being shot down.
 
[[File:TheGambitStoryPage154.png|thumb|right|150px|Ground-resolution distance achieved by KH-8]]
There have been hundreds of [[reconnaissance satellite]]s launched by dozens of nations since the first years of space exploration. Satellites for imaging intelligence were usually placed in [[low-earth orbit|low-earth]], high-inclination orbits, sometimes in [[sun-synchronous orbit]]s. Since the film-return missions were usually short, they could indulge in orbits with low [[perigee]]s, in the range of 100–200&nbsp;km, but the more recent CCD-based satellites have been launched into higher orbits, 250–300&nbsp;km perigee, allowing each to remain in orbit for several years. While the exact [[Optical resolution|resolution]] and other details of modern [[spy satellite]]s are classified, some idea of the trade-offs available can be made using simple physics. The formula for the highest possible resolution of an optical system with a circular aperture is given by the '''[[Lord Rayleigh|Rayleigh]] criterion''':
 
:<math> \sin \theta = 1.22 \frac{\lambda}{D}</math>
 
and
 
:<math> \sin \theta =  \frac{size}{distance}</math>
 
we can get
 
:<math> size =  1.22\frac{\lambda}{D}distance</math>
 
where ''θ'' is the angular resolution, ''λ'' is the [[wavelength]] of light, and ''D'' is the diameter of the lens or mirror. Were the [[Hubble Space Telescope]], with a 2.4 m telescope, designed for photographing Earth, it would be diffraction-limited to resolutions greater than 16&nbsp;cm (6&nbsp;inches) for green light (<math> \lambda \approx  550</math> nm) at its orbital altitude of 590&nbsp;km. This means that it would be impossible to take photographs showing objects smaller than 16&nbsp;cm with such a telescope at such an altitude.  Modern U.S. IMINT satellites are believed to have around 10&nbsp;cm resolution; contrary to references in popular culture, this is sufficient to detect any type of vehicle, but not to read the headlines of a newspaper.<ref>{{cite web|url=http://www.fas.org/irp/imint/resolve5.htm|publisher=Federation of American Scientists|title=Imint resolution comparison}}</ref>
 
The primary purpose of most spy satellites is to monitor visible ground activity. While [[Image resolution|resolution]] and clarity of images has improved greatly over the years, this role has remained essentially the same. Some other uses of satellite imaging have been to produce detailed 3D maps for use in operations and missile guidance systems, and to monitor normally invisible information such as the growth levels of a country's crops or the heat given off by certain facilities. Some of the multi-spectral sensors, such as thermal measurement, are more [[electro-optical MASINT]] than true IMINT platforms.
 
To counter the threat posed by these 'eyes in the sky', the [[United States]], [[Soviet Union|USSR]]/[[Russia]], [[China]] and possibly others, have developed [[anti-satellite weapon|systems for destroying enemy spy satellites]] (either with the use of another 'killer satellite', or with some sort of Earth- or air-launched missile).
 
Since 1985, commercial vendors of satellite imagery have entered the market, beginning with the French [[SPOT (satellites)|SPOT]] satellites, which had resolutions between 5 and 20 metres. Recent high-resolution ( 4 - 0.5 metre) private imaging satellites include [[TerraSAR-X]], [[IKONOS]], [[Orbview]], [[QuickBird]] and [[Worldview-1]], allowing any country (or any business for that matter) to buy access to satellite images.
 
==See also==
* [[Dino Brugioni|Dino A. Brugioni]]
* [[Defence Imagery and Geospatial Organisation]] (DIGO) from [[Australia]]
* [[Geospatial Intelligence]] (GEOINT)
* [[Geographic information systems in geospatial intelligence|GIS in GEOINT]]
* [[JARIC]] (UK interpretation center)
* [[Arthur C. Lundahl]]
* [[Measurement and signature intelligence]] (MASINT)
* [[National Geospatial-Intelligence Agency]] (U.S. interpretation center)
* [[RAF Intelligence]]: [[Royal Air Force]] Intelligence Branch
 
== Notes ==
<references />
 
== Further reading ==
* Maya Quiñones, William Gould, and Carlos D. Rodríguez-Pedraza. [[United States Department of Agriculture]] [http://www.fas.org/irp/imint/haiti.pdf Geospatial Data Availability for Haiti] (February 2007) (Study on availability of commercial imagery in 2007 which summarizes collection systems and data products.)
 
== External links ==
*[http://www.globalsecurity.org/intell/library/imint/imint_101.htm Introduction to Imagery Intelligence via globalsecurity]
*[http://www.globalcollab.org/Nautilus/australia/australian-defence-facilities/australian-defence-satellite-communications-station-geraldton/australian-defence-satellite-communications-station/ Australian Defence Satellite Communications Station, Geraldton]
*[http://www.globalcollab.org/Nautilus/australia/australian-defence-facilities/pine-gap Joint Australian-US intelligence facility - Pine Gap]
 
{{Q-UAVs}}
{{Intelligence cycle management}}
 
[[Category:Intelligence gathering disciplines]]
[[Category:Intelligence (information gathering)]]
[[Category:Photography by genre]]

Revision as of 19:45, 7 February 2014

Promoting property can be quite a daunting job, specifically in the current market place environment. Many individuals consider they will need to acquire massive reductions in the importance to be able to market. But, that is certainly not always true. Browse the ideas in this post to further improve your odds of accomplishment!

In case your house has been on the market for a while, include a new picture of your house that exhibits the actual year and climate. An more aged photograph will make it clear that the property has become listed for quite a while, producing consumers prone to put in the lowest supply.

When promoting your house, have a real estate appraisal completed before you decide to talk to a real estate professional. An appraiser uses several of the exact same information and facts that a realtor does, but is undoubtedly an impartial assessor of value. An appraiser can give you an acceptable concept of what you could count on for your home, as well as reveal to you evidence of her or his findings.

Number of architectural capabilities time a property a lot more than popcorn ceilings so eliminating them would be a great home remodeling for individuals planning to promote their residence. The task need to consider no longer when compared to a saturday and sunday as soon as full you should have a ceiling that is certainly much easier to color and maintenance, along with a residence with an interior that won't turn aside potential customers.

When improving a property to offer, concentrate on obvious improvements first. Upgrading the furnace or setting up warmed up flooring surfaces will be all well and good, however, if the roof top spills consumers will be turned away. You will have a much better probability of getting a profit on your own investment through making sure the outside exterior siding or indoor painting seems very good very first.

If you are selling your house you need to be specifically cautious about the way you selling price your home. You need to find out the cost of the most expensive and cheapest homes in your neighborhood and stay a place in between. Should you price your home excessive and want to keep lowering the value it will give a alert sign to potential buyers.

One particular tip to remember in terms of offering your real estate sells-estate, is you need to be aware of the existing problem of the marketplace and make sure that you change your house cost consequently. This will help to actually have the ability to easily and reasonably sell your property in the tough industry.

In case you are promoting a condo, check with your connection about the policies about lock cases. If the condo does not permit lock cases, try and Dean Graziosi Visit The Website shape some thing by helping cover their your real estate professional making it as effortless for that potential shopper as possible. You would like to make a beneficial effect not only along with your condominium although the organization they might need to deal with. So try out making it as convenient as you possibly can.

Including perks inside your supply can sometimes help a home to sell speedier. Offer you to add the blinds or even a new washing machine and dryer. Display a motivation to spend some shutting down charges or have at home warrantee. Such advantages may be attractive to a customer and will make you stick out versus the competition.

When thinking about the addition of an area to your house, employ current room and conserve huge. It is rather costly to add more base to your property or lengthen the roof to accommodate another area, along with the excess labor. Think about the possibilities of remodeling the attic room or concluding the basements to provide space and benefit to your residence.

These tips have already been designed to help you with real-estate marketing attempts. They should be an excellent asset to anybody who is selling any type of whole lot or residence. Although the industry is at present within a slump, that doesn't suggest your costs need to be too.