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Astronomical Timer
A time switch (also called a timer switch, or simply timer) is a timer that operates an electric switch controlled by the timing mechanism. Intermatic introduced its first time switch in 1945, which was used for "electric signs, store window lighting, apartment hall lights, stokers, and oil and gas burners." A consumer version was added in 1952. The switch may be connected to an electric circuit operating from mains power, including via a relay or contactor; or low voltage, including battery-operated equipment in vehicles. It may be built into power circuits (as with a central heating or water heater timer), plugged into a wall outlet with equipment plugged into the timer instead of directly into the power point; or built into equipment. Types Sleep timer A sleep timer is a function on many modern televisions and other electronic devices that shuts off the power after a preset amount of time. The setting is usually made either from the remote control of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Time Switch
A time switch (also called a timer switch, or simply timer) is a timer that operates an electric switch controlled by the timing mechanism. Intermatic introduced its first time switch in 1945, which was used for "electric signs, store window lighting, apartment hall lights, stokers, and oil and gas burners." A consumer version was added in 1952. The switch may be connected to an electric circuit operating from mains power, including via a relay or contactor; or low voltage, including battery-operated equipment in vehicles. It may be built into power circuits (as with a central heating or water heater timer), plugged into a wall outlet with equipment plugged into the timer instead of directly into the power point; or built into equipment. Types Sleep timer A sleep timer is a function on many modern televisions and other electronic devices that shuts off the power after a preset amount of time. The setting is usually made either from the remote control of the device or the de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Remote Control
In electronics, a remote control (also known as a remote or clicker) is an electronic device used to operate another device from a distance, usually wirelessly. In consumer electronics, a remote control can be used to operate devices such as a television set, DVD player or other home appliance. A remote control can allow operation of devices that are out of convenient reach for direct operation of controls. They function best when used from a short distance. This is primarily a convenience feature for the user. In some cases, remote controls allow a person to operate a device that they otherwise would not be able to reach, as when a garage door opener is triggered from outside. Early television remote controls (1956–1977) used ultrasonic tones. Present-day remote controls are commonly consumer infrared devices which send digitally-coded pulses of infrared radiation. They control functions such as power, volume, channels, playback, track change, heat, fan speed, and vario ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light Sensor
Photodetectors, also called photosensors, are sensors of light or other electromagnetic radiation. There is a wide variety of photodetectors which may be classified by mechanism of detection, such as photoelectric or photochemical effects, or by various performance metrics, such as spectral response. Semiconductor-based photodetectors typically photo detector have a p–n junction that converts light photons into current. The absorbed photons make electron–hole pairs in the depletion region. Photodiodes and photo transistors are a few examples of photo detectors. Solar cells convert some of the light energy absorbed into electrical energy. Types Photodetectors may be classified by their mechanism for detection: * Photoemission or photoelectric effect: Photons cause electrons to transition from the conduction band of a material to free electrons in a vacuum or gas. * Thermal: Photons cause electrons to transition to mid-gap states then decay back to lower bands, inducing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algorithm
In mathematics and computer science, an algorithm () is a finite sequence of rigorous instructions, typically used to solve a class of specific Computational problem, problems or to perform a computation. Algorithms are used as specifications for performing calculations and data processing. More advanced algorithms can perform automated deductions (referred to as automated reasoning) and use mathematical and logical tests to divert the code execution through various routes (referred to as automated decision-making). Using human characteristics as descriptors of machines in metaphorical ways was already practiced by Alan Turing with terms such as "memory", "search" and "stimulus". In contrast, a Heuristic (computer science), heuristic is an approach to problem solving that may not be fully specified or may not guarantee correct or optimal results, especially in problem domains where there is no well-defined correct or optimal result. As an effective method, an algorithm ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Season
A season is a division of the year based on changes in weather, ecology, and the number of daylight hours in a given region. On Earth, seasons are the result of the axial parallelism of Earth's tilted orbit around the Sun. In temperate and polar regions, the seasons are marked by changes in the intensity of sunlight that reaches the Earth's surface, variations of which may cause animals to undergo hibernation or to migrate, and plants to be dormant. Various cultures define the number and nature of seasons based on regional variations, and as such there are a number of both modern and historical cultures whose number of seasons varies. The Northern Hemisphere experiences most direct sunlight during May, June, and July, as the hemisphere faces the Sun. The same is true of the Southern Hemisphere in November, December, and January. It is Earth's axial tilt that causes the Sun to be higher in the sky during the summer months, which increases the solar flux. However, due to seas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coffee
Coffee is a drink prepared from roasted coffee beans. Darkly colored, bitter, and slightly acidic, coffee has a stimulant, stimulating effect on humans, primarily due to its caffeine content. It is the most popular hot drink in the world. Seeds of the ''Coffea'' plant's fruits are separated to produce unroasted green coffee beans. The beans are Coffee roasting, roasted and then ground into fine particles that are typically steeped in hot water before being filtered out, producing a cup of coffee. It is usually served hot, although chilled or iced coffee is common. Coffee can be prepared and presented in a variety of ways (e.g., espresso, French press, caffè latte, or already-brewed canned coffee). Sugar, sugar substitutes, milk, and cream are often used to mask the bitter taste or enhance the flavor. Though coffee is now a global commodity, it has a History of coffee, long history tied closely to food traditions around the Red Sea. The earliest credible evidence of coffee d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morning
Morning is the period from sunrise to noon. There are no exact times for when morning begins (also true of evening and night) because it can vary according to one's lifestyle and the hours of daylight at each time of year. However, morning strictly ends at noon, which is when afternoon starts. Morning can also be defined as starting from midnight to noon. Morning precedes afternoon, evening, and night in the sequence of a day. Originally, the term referred to sunrise. Etymology The Modern English words "morning" and "tomorrow" began in Middle English as , developing into , then , and eventually . English, unlike some other languages, has separate terms for "morning" and "tomorrow", despite their common root. Other languages, like Dutch, Scots and German, may use a single wordto signify both "morning" and "tomorrow". Significance Greeting Some languages that use the time of day in greeting have a special greeting for morning, such as the English good morning. The appropriat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coffee Maker
A coffeemaker, coffee maker or coffee machine is a cooking appliance used to brew coffee. While there are many different types of coffeemakers the two most common brewing principles use gravity or pressure to move hot water through coffee grounds. In the most common devices, coffee grounds are placed into a paper or metal filter inside a funnel, which is set over a glass or ceramic coffee pot, a cooking pot in the kettle family. Cold water is poured into a separate chamber, which is then boiled and directed into the funnel and allowed to drip through the grounds under gravity. This is also called '' automatic drip-brew''. Coffee makers that use pressure to force water through the coffee grounds are called espresso makers, and they produce espresso coffee. Types Vacuum brewers On August 27, 1930, Inez H. Peirce of Chicago, Illinois, filed her patent for the first vacuum coffee maker that truly automated the vacuum brewing process, while eliminating the need for a stovetop bur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supper
Supper was originally a secondary lighter evening meal. The main meal of the day, called dinner, used to be served closer to what is known as lunchtime, around the middle of the day, but crept later over the centuries, mostly over the course of the 19th century. When dinner was still at the early time, eating a lighter supper in the evening was very common; it was not always the last meal of the day, as there might be a tea later. Reflecting the typical custom of 17th century elites, Louis XIV dined at noon, with a supper at 10p.m. Even when dinner was in the early evening, supper was served at a ball, or after returning from it, and might be after other evening excursions. At an English ball in 1791, supper was served to 140 guests at 1:00 a.m. They would all have had dinner at home many hours earlier, before coming out. Other, grander, balls served supper even later, up to 3:30 a.m., at a London ball given in 1811 by the Duchess of Bedford. The modern usage of "supper" varies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slow Cooker
A slow cooker, also known as a crock-pot (after a trademark owned by Sunbeam Products but sometimes used generically in the English-speaking world), is a countertop electrical cooking appliance used to simmer at a lower temperature than other cooking methods, such as baking, boiling, and frying. This facilitates unattended cooking for many hours of dishes that would otherwise be boiled: pot roast, soups, stews and other dishes (including beverages, desserts and dips). History Slow cookers achieved popularity in the US during the 1940s, when many women began to work outside the home. They could start dinner cooking in the morning before going to work and finish preparing the meal in the evening when they came home. The Naxon Utilities Corporation of Chicago, under the leadership of electrical engineer Irving Naxon (born Irving Nachumsohn), developed the Naxon Beanery All-Purpose Cooker for the purposes of cooking a bean meal. Naxon was inspired by a story from his mother whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Countdown
A countdown is a sequence of backward counting to indicate the time remaining before an event is scheduled to occur. NASA commonly employs the terms "L-minus" and "T-minus" during the preparation for and anticipation of a rocket launch, and even "E-minus" for events that involve spacecraft that are already in space, where the "T" could stand for "Test" or "Time", and the "E" stands for "Encounter", as with a comet or some other space object. Other events for which countdowns are commonly used include the detonation of an explosive, the start of a race, the start of the New Year, or any anxiously anticipated event. An early use of a countdown once signaled the start of a Cambridge University rowing race. One of the first known associations with rockets was in the 1929 German science fiction movie ''Frau im Mond'' (English: ''Woman in the Moon'') written by Thea von Harbou and directed by Fritz Lang in an attempt to increase the drama of the launch sequence of the story's lunar-bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semiconductor
A semiconductor is a material which has an electrical resistivity and conductivity, electrical conductivity value falling between that of a electrical conductor, conductor, such as copper, and an insulator (electricity), insulator, such as glass. Its electrical resistivity and conductivity, resistivity falls as its temperature rises; metals behave in the opposite way. Its conducting properties may be altered in useful ways by introducing impurities ("doping (semiconductor), doping") into the crystal structure. When two differently doped regions exist in the same crystal, a semiconductor junction is created. The behavior of charge carriers, which include electrons, ions, and electron holes, at these junctions is the basis of diodes, transistors, and most modern electronics. Some examples of semiconductors are silicon, germanium, gallium arsenide, and elements near the so-called "metalloid staircase" on the periodic table. After silicon, gallium arsenide is the second-most common s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
