1.
Geographic coordinate system
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A geographic coordinate system is a coordinate system used in geography that enables every location on Earth to be specified by a set of numbers, letters or symbols. The coordinates are chosen such that one of the numbers represents a vertical position. A common choice of coordinates is latitude, longitude and elevation, to specify a location on a two-dimensional map requires a map projection. The invention of a coordinate system is generally credited to Eratosthenes of Cyrene. Ptolemy credited him with the adoption of longitude and latitude. Ptolemys 2nd-century Geography used the prime meridian but measured latitude from the equator instead. Mathematical cartography resumed in Europe following Maximus Planudes recovery of Ptolemys text a little before 1300, in 1884, the United States hosted the International Meridian Conference, attended by representatives from twenty-five nations. Twenty-two of them agreed to adopt the longitude of the Royal Observatory in Greenwich, the Dominican Republic voted against the motion, while France and Brazil abstained. France adopted Greenwich Mean Time in place of local determinations by the Paris Observatory in 1911, the latitude of a point on Earths surface is the angle between the equatorial plane and the straight line that passes through that point and through the center of the Earth. Lines joining points of the same latitude trace circles on the surface of Earth called parallels, as they are parallel to the equator, the north pole is 90° N, the south pole is 90° S. The 0° parallel of latitude is designated the equator, the plane of all geographic coordinate systems. The equator divides the globe into Northern and Southern Hemispheres, the longitude of a point on Earths surface is the angle east or west of a reference meridian to another meridian that passes through that point. All meridians are halves of great ellipses, which converge at the north and south poles, the prime meridian determines the proper Eastern and Western Hemispheres, although maps often divide these hemispheres further west in order to keep the Old World on a single side. The antipodal meridian of Greenwich is both 180°W and 180°E, the combination of these two components specifies the position of any location on the surface of Earth, without consideration of altitude or depth. The grid formed by lines of latitude and longitude is known as a graticule, the origin/zero point of this system is located in the Gulf of Guinea about 625 km south of Tema, Ghana. To completely specify a location of a feature on, in, or above Earth. Earth is not a sphere, but a shape approximating a biaxial ellipsoid. It is nearly spherical, but has an equatorial bulge making the radius at the equator about 0. 3% larger than the radius measured through the poles, the shorter axis approximately coincides with the axis of rotation
2.
North Saskatchewan River
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The North Saskatchewan River is a glacier-fed river that flows east from the Canadian Rockies to central Saskatchewan. It is one of two rivers that join to make up the Saskatchewan River. The Saskatchewan River system is the largest shared between the Canadian provinces of Alberta and Saskatchewan and it includes most of southern Alberta and southern Saskatchewan, before crossing into central Manitoba. North Saskatchewan River has a length of 1,287 kilometres, at its end point at Saskatchewan River Forks it has a mean discharge of 245 cubic metres per second. The yearly discharge at the Alberta–Saskatchewan border is more than 7 cubic kilometres, the river begins above 1,800 metres at the toe of the Saskatchewan Glacier in the Columbia Icefield, and flows southeast through Banff National Park alongside the Icefields Parkway. At the junction of the David Thompson Highway, it turns northeast for 10 kilometres before switching to a more direct eastern flow for about 30 kilometres. At this point, it turns north where it arrives at Abraham Lake. Bighorn Dam constricts the north end of Abraham Lake, where the North Saskatchewan emerges to track eastward to Rocky Mountain House, at Rocky Mountain House, the river abruptly turns north again for 100 kilometres where it switches east towards Edmonton, Alberta. From the border, the river flows southeast between North Battleford and Battleford and on in the direction of Saskatoon, about 40 kilometres northwest of Saskatoon, near Langham, the river veers to the northeast where it passes through the City of Prince Albert. About 30 kilometres downstream of Prince Albert, the North Saskatchewan River joins the South Saskatchewan River at Saskatchewan River Forks to become the Saskatchewan River, from there, the river flows east to Tobin Lake and into Manitoba, eventually emptying into Lake Winnipeg. The river course can be divided into five distinct sections, the first, the eastern slopes of the Rocky Mountains, is the smallest area geographically, although the largest in terms of run-off and contributed water flow. The glaciers and perpetual snows of the mountain feed the river year-round. Mountains, with vegetation, experience fast-melting snow cover. The second section of the river comprises the foothills region, the terrain is hilly and rough, with a deeper and more defined valley. This area is covered with forest and muskeg, and run-off into the river is much more constant. From Edmonton to the mouth of the Vermilion River, the North Saskatchewan flows through the plains-parkland divide, the North Saskatchewan River valley parks system, the largest expanses of urban parkland in Canada. Cutting across Edmonton and the Capital Region, the valley of the river is much wider, and the river itself spreads out across shallow water and flows over many shifting sand bars. Low-lying, flat areas, border the river for much of this section, the final section of the river, from Prince Albert to the Saskatchewan River Forks, has many rapids
3.
Edmonton
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Edmonton /ˈɛdməntən/ is the capital city of the Canadian province of Alberta. Edmonton is on the North Saskatchewan River and is the centre of the Edmonton Capital Region, the city anchors the north end of what Statistics Canada defines as the Calgary–Edmonton Corridor. The city had a population of 932,546 in 2016, making it Albertas second-largest city, also in 2016, Edmonton had a metropolitan population of 1,321,426, making it the sixth-largest census metropolitan area in Canada. Edmonton is North Americas northernmost city with a population over one million. A resident of Edmonton is known as an Edmontonian, Edmontons historic growth has been facilitated through the absorption of five adjacent urban municipalities and a series of annexations ending in 1982. Known as the Gateway to the North, the city is a point for large-scale oil sands projects occurring in northern Alberta. Edmonton is a cultural, governmental and educational centre and it hosts a year-round slate of festivals, reflected in the nickname Canadas Festival City. It is home to North Americas largest mall, West Edmonton Mall, in 1754, Anthony Henday, an explorer for the Hudsons Bay Company, may have been the first European to enter the Edmonton area. By 1795, Fort Edmonton was established on the north bank as a major trading post for the Hudsons Bay Company. The new forts name was suggested by John Peter Pruden after Edmonton, London, the home town of both the HBC deputy governor Sir James Winter Lake, and Pruden. In 1876, Treaty 6, which includes what is now Edmonton, was signed between the Aboriginal peoples in Canada and Queen Victoria as Queen of Canada, as part of the Numbered Treaties of Canada. The agreement includes the Plains and Woods Cree, Assiniboine, and other governments of First Nations at Fort Carlton, Fort Pitt. The area covered by the treaty represents most of the area of the current provinces of Saskatchewan. The arrival of the CPR and the C&E Railway helped bring settlers and entrepreneurs from eastern Canada, Europe, U. S. the Edmonton areas fertile soil and cheap land attracted settlers, further establishing Edmonton as a major regional commercial and agricultural centre. Some people participating in the Klondike Gold Rush passed through South Edmonton/Strathcona in 1897, in November 1905, the Canadian Northern Railway arrived in Edmonton, accelerating growth. During the early 1900s, Edmontons rapid growth led to speculation in real estate, in 1912, Edmonton amalgamated with the City of Strathcona, south of the North Saskatchewan River, as a result, the city extended south of the North Saskatchewan River for the first time. Just prior to World War I, the boom ended, many impoverished families moved to subsistence farms outside the city, while others fled to greener pastures in other provinces. Recruitment to the Canadian army during the war contributed to the drop in population
4.
Truss bridge
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A truss bridge is a bridge whose load-bearing superstructure is composed of a truss, a structure of connected elements usually forming triangular units. The connected elements may be stressed from tension, compression, or sometimes both in response to dynamic loads, Truss bridges are one of the oldest types of modern bridges. The basic types of truss bridges shown in this article have simple designs which could be analyzed by 19th-. A truss bridge is economical to construct because it uses materials efficiently, the nature of a truss allows the analysis of the structure using a few assumptions and the application of Newtons laws of motion according to the branch of physics known as statics. For purposes of analysis, trusses are assumed to be pin jointed where the components meet. This assumption means that members of the truss will act only in tension or compression, a more complex analysis is required where rigid joints impose significant bending loads upon the elements, as in a Vierendeel truss. The central vertical member stabilizes the upper member, preventing it from buckling. If the top member is sufficiently stiff then this element may be eliminated. If the lower chord is sufficiently resistant to bending and shear, the vertical elements may be eliminated. The ability to distribute the forces in various ways has led to a variety of truss bridge types. In other cases the appearance of the structure may take on greater importance, a pure truss can be represented as a pin-jointed structure, one where the only forces on the truss members are tension or compression, not bending. This is used in the teaching of statics, by the building of bridges from spaghetti. Spaghetti is brittle and although it can carry a modest tension force, a model spaghetti bridge thus demonstrates the use of a truss structure to produce a usefully strong complete structure from individually weak elements. In 1820 a simple form of truss, Towns lattice truss, was patented, few iron truss bridges were built in the United States before 1850. Truss bridges became a type of bridge built from the 1870s through the 1930s. Examples of these still remain across the US, but their numbers are dropping rapidly. As metal slowly started to replace timber, wrought iron bridges in the US started being built on a scale in the 1870s. Bowstring truss bridges were a common truss design during this time, companies like the Massillon Bridge Company of Massillon, Ohio and the King Bridge Company of Cleveland, Ohio became well-known, as they marketed their designs to cities and townships
5.
Grating
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A grating is any regularly spaced collection of essentially identical, parallel, elongated elements. Gratings usually consist of a set of elongated elements. When the two sets are perpendicular, this is known as a grid or a mesh. Grating can also come in 4 feet or 2 feet x 8 feet panels which are used for decks on bridges, footbridges. Other panel sizes may also be available, Grating can be made of different materials like steel, aluminum, fiberglass. Fiberglass grating is also known as FRP Grating, a grating covering a drain can be a collection of iron bars held together by a lighter iron frame. Gratings over drains and air vents are used as filters, to block movement of large particles, Grating can also be a diffraction grating, a reflecting or transparent optical component on which there are many fine, parallel, equally spaced grooves. A grating can also be a picture having the characteristics of a grating, for example, a picture might be of a collection of parallel black bars separated by equal-sized white bars. These sorts of gratings are described by a graph, on the y-axis of the graph is the luminance obtained by moving a light meter over the grating perpendicular to the orientation of the grating. On the x-axis of the graph is the distance the light meter moved, the example is a square-wave grating, the graph consists of flat, low lines, with abrupt corners leading to flat high lines. One period of such a grating consists of one black bar, gratings where the black bars have a different width from the white bars are rectangular and are described by the duty cycle. The duty cycle is the ratio of width of the bar to period. Gratings are usually specified by four parameters, spatial frequency is the number of cycles occupying a particular distance. Contrast is a measure of the difference in luminance between the parts of the grating and the dark parts. It is usually expressed as Michelson contrast, the maximum luminance minus the minimum luminance divided by the maximum luminance plus the minimum luminance, phase is the position of the graph relative to some standard position. It is usually measured in degrees or in radians, orientation is the angle the grating makes with some standard orientation. It is also measured in degree or in radians. Grating elements can have other than that of sharp-edged bars
6.
Dominion Bridge Company
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Dominion Bridge Company Limited was a Canadian steel bridge constructor originally based in Lachine, Quebec. From the core business of steel bridge component fabrication, the company diversified into related areas such as the fabrication of holding tanks for pulp mills and skyscraper framing. Other Canadian plants were located in Amherst, NS, Toronto, ON, Winnipeg, MB, Regina, SK, Saskatoon, SK, Calgary, AB, Edmonton, AB, Richmond, BC and Burnaby, BC. In the 1960s and 1970s, Dominion Bridge expanded internationally and renamed itself AMCA International and this name was later changed to United Dominion Industries. To keep name recognition alive, the continued to call its Canadian division Dominion Bridge. Between 1979-1988, the companys Lachine plant operated under the auspices of a subsidiary called Dominion Bridge-Sulzer Inc. which was co-owned by AMCA International, the Dominion Bridge facility in Burnaby, BC operated from 1930 until the mid-1970s at a 15-acre property located at 2400 Boundary Road. After being sold, this property was repurposed to become The Bridge Studios, in 1886, the company began to build a cantilevered bridge over the St. Lawrence River for the Canadian Pacific Railway. Because part of the lay in the reservation of the Kahnawake and Akwesasne Mohawks. The company planned to use them as unskilled labour but they climbed all over the bridge, without fear, and asked to become riveters. They proved to have an aptitude for the work and by the end of the project there were 70 iron and steel riveters in the Kahnawake band. In 1890 civil engineer for various railways James Ross replaced Job Abbott as president of the company, although credited to the drive of Ross, vice-president James Pawley Dawes lead the developed via joint-venture the St Lawrence Bridge Company to construct the Quebec Bridge. George Herrick Duggan joined the Engineering Department in 1886, becoming Chief Engineer in 1901, another notable employee was Philip Louis Pratley, a Persons of National Historic Significance. In 1898 the Dominion Bridge Company was awarded the contract to design and build the Alexandra Bridge, at the time of completion in 1901 the Alexandra Bridge was the fourth longest cantilever span in the world. This facility provided steel for the building of the Prince Edward Viaduct, with a lowest bid of $6,954,000, the company secured the contract to erect the steel superstructure of the Jacques Cartier Bridge linking Montreal to the South Shore on October 25,1925. The company also raised the Honoré Mercier Bridge as part of the same programme and it had built the original bridge between 1932 and 1934 using steel caissons assembled by Dufresne Engineering from plates manufactured at Dominions Lachine yards. The companys Canadian operations experienced a decline after work was completed on projects for Montreals Olympic Games in 1976. The Burnaby plant was shut down in the mid-1970s and the Toronto plant was closed in 1990, after the dissolution of Dominion Bridge-Sulzer Inc. and several buildings on the property of the Lachine plant were mothballed or torn down following the dissolution. Employment at the Lachine plant alone dropped from approximately 2,000 in the early 1970s to about 250 in 1990, in 1993, the Cedar Group acquired United Dominion Industries Dominion Bridge subsidiary, which was then a four-plant operation
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