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The Earth and Its Coordinate System
Published in Terry A. Slocum, Robert B. McMaster, Fritz C. Kessler, Hugh H. Howard, Thematic Cartography and Geovisualization, 2022
Terry A. Slocum, Robert B. McMaster, Fritz C. Kessler, Hugh H. Howard
Describing a point on Earth's surface requires that a location's latitude and longitude be known with respect to an origin. In the case of latitude, the Equator serves as a convenient origin because it divides Earth into two equal halves. Figure 7.2A illustrates lines of latitude, shown as thin red lines, with the Equator represented by the thicker red line. Because lines of latitude are parallel to each other, they are often called parallels. Latitude values are reported in angular measurements of degrees, minutes, and seconds. Similar in concept to units of time, this sexagesimal system has a base unit of 60 (the decimal system's base unit is 10), where each degree is divided into 60 minutes and each minute is divided again into 60 seconds. In this system, the ° symbol denotes the number of degrees, a single quote (′) indicates minutes, and double quotes (″) specify the number of seconds. There are 90° of latitude north and south of the Equator (designated as 0°) for a total of 180° from pole to pole. It is customary to apply the terms North and South to designate latitude locations above or below the Equator. In some cases, plus (+) and minus (–) signs are attached as a prefix to the degree values, indicating latitude locations above and below the Equator, respectively. Thus, the latitude of the Washington Monument can be specified as 38° 53′ 22″ N or +38° 53′ 22″.
The Earth–Sun Relationship
Published in Matt Fajkus, Dason Whitsett, Architectural Science and the Sun, 2018
Latitude (L) is the measure of north-south position on Earth. Specifically, it is the absolute angular distance from the center of the equatorial plane to a point on the surface of the Earth. Latitude ranges from 0° at the equator to 90° at the North Pole and −90° at the South Pole. The imaginary lines that connect all points of the same latitude are known as parallels. Except for the equator, parallels are minor circles. As shown in Figure 2.6, when viewed from the north or south, parallels appear to be concentric circles. When viewed from the equatorial plane, they are parallel lines. Because lines of latitude are parallel and separated by the same angular distance on the surface of the Earth, the distance between parallels is constant. The circumference of the Earth is approximately 40,008 km around the poles, resulting in a surface distance for each degree of latitude of approximately 111.3 km.
Arctic Weather and Climate Patterns
Published in Neloy Khare, Climate Change in the Arctic, 2022
R. S. Maheskumar, S Sunitha Devi
The Arctic is a polar region situated around the North Pole, consisting of the Arctic Ocean and the adjoining land region. The Arctic region is defined as the northernmost part of the globe lying north of the latitude 66.5°N. North of this latitudinal belt, Sun does not set on the June solstice and does not rise on the December solstice. Around the Arctic Circle towards the North Pole, the durations of day and night are shorter. North pole experiences continuous 6 months daylight and 6 months constant night as the Sun rises and sets only once in a year. The Arctic Ocean is a large and unique one partially covered by ice and partly surrounded by the land region belonging to different countries.
Experimental investigation of a solar air heater with copper wool on the absorber plate
Published in International Journal of Green Energy, 2020
Ayşe Biçer, Atilla G Devecioğlu, Vedat Oruç, Zafer Tuncer
“The glazing of SAH was a single-layer glass with a thickness of 5 mm. The collector was insulated with 50 mm-thick glass-wool in order to prevent the heat loss from bottom surface of collector. The inlet and outlet air ducts were circular channel with a diameter of 100 mm. Forced air flow was supplied into the system by means of a duct type fan with a maximum flow rate of 1080 m3/h. The air flow rate was regulated by an installed variac. An aluminum flexible duct with a diameter of 100 mm was connected to the outlet of fan. The long side of SAH was oriented as parallel to the ground. The tilt angle of SAH was set as 25° depending on latitude angle of the city as well as measuring instant. The collector was oriented to south direction exactly so that azimuth angle was kept as zero. Table 2 lists other basic parameters in the experimental investigation.” The insulation was coated with black-painted copper plate having a thickness of 0.30 mm. For comparing the influence of copper wool, the experiments were repeated at the same values of mass flow rate for SAH without copper wool case. The mass flow rate (m.) values were in the investigation were 0.035 kg/s and 0.044 kg/s.
Analysis of spatiotemporal trajectories for stops along taxi paths
Published in Spatial Cognition & Computation, 2018
Liang Huang, Yuanqiao Wen, Xinyue Ye, Chunhui Zhou, Faming Zhang, Jay Lee
In a large city in China, taxis usually play a very important role in transporting people, often crossing boundaries of different districts in the city for a wide variety of activities. These activities may be work, rest, leisure outings and etc. With GPS equipment, movement histories of taxis can be recorded as a series of locations sampled with a small periodic interval (i.e., frequencies of recording GPS signals). Each of such records is a trajectory. Each sampling point in a trajectory represents a record of GPS information, denoted as , in which id is the identification number of taxi, t denotes the record time, lat and lon define the taxi’s position (i.e., latitude and longitude), v denotes the instant velocity, s indicates the service status of the taxi (e.g., vacant or occupied). Table 1 shows several sampling points of taxi trajectories used in this study.
Anomaly detection model of small-scaled ship for maritime autonomous surface ships’ operation
Published in Journal of International Maritime Safety, Environmental Affairs, and Shipping, 2022
Widiastuti Tyasayumranani, Taewoong Hwang, Taemin Hwang, Ik-Hyun Youn
The minimal set of information to discover the trajectories is location and the vessel’s dynamic information; therefore, feature selection is initially important to build the model. The observation uses not only latitude and longitude at an instant but also course and speed as remarkable features to increase the validation rate. The acquired initial raw data to generate each vessel trajectory could be expressed by the following formula: