Bluetooth is a wireless technology standard for exchanging data between fixed and mobile devices over short distances using short-wavelength UHF radio waves in the industrial and medical radio bands, from 2.400 to 2.485 GHz, building personal area networks. It was conceived as a wireless alternative to RS-232 data cables. Bluetooth is managed by the Bluetooth Special Interest Group, which has more than 30,000 member companies in the areas of telecommunication, computing and consumer electronics; the IEEE standardized no longer maintains the standard. The Bluetooth SIG oversees development of the specification, manages the qualification program, protects the trademarks. A manufacturer must meet Bluetooth SIG standards to market it as a Bluetooth device. A network of patents apply to the technology; the development of the "short-link" radio technology named Bluetooth, was initiated in 1989 by Nils Rydbeck, CTO at Ericsson Mobile in Lund, Sweden and by Johan Ullman. The purpose was to develop wireless headsets, according to two inventions by Johan Ullman, SE 8902098-6, issued 1989-06-12 and SE 9202239, issued 1992-07-24.
Nils Rydbeck tasked Tord Wingren with specifying and Jaap Haartsen and Sven Mattisson with developing. Both were working for Ericsson in Lund. Invented by Dutch electrical engineer Jaap Haartsen, working for telecommunications company Ericsson in 1994; the first consumer bluetooth launched in 1999. It was a hand free mobile headset which earned the technology the"Best of show Technology Award" at COMDEX; the first Bluetooth mobile phone was the Sony Ericsson T36 but it was the revised T39 model which made it to store shelves in 2001. The name Bluetooth is an Anglicised version of the Scandinavian Blåtand/Blåtann, the epithet of the tenth-century king Harald Bluetooth who united dissonant Danish tribes into a single kingdom; the implication is. The idea of this name was proposed in 1997 by Jim Kardach of Intel who developed a system that would allow mobile phones to communicate with computers. At the time of this proposal he was reading Frans G. Bengtsson's historical novel The Long Ships about Vikings and King Harald Bluetooth.
The Bluetooth logo is a bind rune merging the Younger Futhark runes and, Harald's initials. Bluetooth operates at frequencies between 2402 and 2480 MHz, or 2400 and 2483.5 MHz including guard bands 2 MHz wide at the bottom end and 3.5 MHz wide at the top. This is in the globally unlicensed industrial and medical 2.4 GHz short-range radio frequency band. Bluetooth uses. Bluetooth divides transmitted data into packets, transmits each packet on one of 79 designated Bluetooth channels; each channel has a bandwidth of 1 MHz. It performs 1600 hops per second, with adaptive frequency-hopping enabled. Bluetooth Low Energy uses 2 MHz spacing. Gaussian frequency-shift keying modulation was the only modulation scheme available. Since the introduction of Bluetooth 2.0+EDR, π/4-DQPSK and 8-DPSK modulation may be used between compatible devices. Devices functioning with GFSK are said to be operating in basic rate mode where an instantaneous bit rate of 1 Mbit/s is possible; the term Enhanced Data Rate is used to describe π/4-DPSK and 8-DPSK schemes, each giving 2 and 3 Mbit/s respectively.
The combination of these modes in Bluetooth radio technology is classified as a BR/EDR radio. Bluetooth is a packet-based protocol with a master/slave architecture. One master may communicate with up to seven slaves in a piconet. All devices share the master's clock. Packet exchange is based on the basic clock, defined by the master, which ticks at 312.5 µs intervals. Two clock ticks make up a slot of 625 µs, two slots make up a slot pair of 1250 µs. In the simple case of single-slot packets, the master transmits in slots and receives in odd slots; the slave, receives in slots and transmits in odd slots. Packets may be 1, 3 or 5 slots long, but in all cases the master's transmission begins in slots and the slave's in odd slots; the above excludes Bluetooth Low Energy, introduced in the 4.0 specification, which uses the same spectrum but somewhat differently. A master BR/EDR Bluetooth device can communicate with a maximum of seven devices in a piconet, though not all devices reach this maximum; the devices can switch roles, by agreement, the slave can become the master.
The Bluetooth Core Specification provides for the connection of two or more piconets to form a scatternet, in which certain devices play the master role in one piconet and the slave role in another. At any given time, data can be transferred between one other device; the master chooses. Since it is the master that chooses which slave to address, whereas a slave is supposed to listen in each receive slot, being a master is a lighter burden than being a slave. Being a master of seven slaves is possible; the specification is vague as to required behavior in scatternets. Bluetooth is a standard wire-replacement communications proto
An accelerometer is a device that measures proper acceleration. Proper acceleration, being the acceleration of a body in its own instantaneous rest frame, is not the same as coordinate acceleration, being the acceleration in a fixed coordinate system. For example, an accelerometer at rest on the surface of the Earth will measure an acceleration due to Earth's gravity, straight upwards of g ≈ 9.81 m/s2. By contrast, accelerometers in free fall will measure zero. Accelerometers have multiple applications in science. Sensitive accelerometers are components of inertial navigation systems for aircraft and missiles. Accelerometers are used to monitor vibration in rotating machinery. Accelerometers are used in tablet computers and digital cameras so that images on screens are always displayed upright. Accelerometers are used in drones for flight stabilisation. Coordinated accelerometers can be used to measure differences in proper acceleration gravity, over their separation in space; this gravity gradiometry is useful because absolute gravity is a weak effect and depends on local density of the Earth, quite variable.
Single- and multi-axis models of accelerometer are available to detect magnitude and direction of the proper acceleration, as a vector quantity, can be used to sense orientation, coordinate acceleration, vibration and falling in a resistive medium. Micromachined microelectromechanical systems accelerometers are present in portable electronic devices and video game controllers, to detect the position of the device or provide for game input. An accelerometer measures proper acceleration, the acceleration it experiences relative to freefall and is the acceleration felt by people and objects. Put another way, at any point in spacetime the equivalence principle guarantees the existence of a local inertial frame, an accelerometer measures the acceleration relative to that frame; such accelerations are popularly denoted g-force. An accelerometer at rest relative to the Earth's surface will indicate 1 g upwards, because any point on the Earth's surface is accelerating upwards relative to the local inertial frame.
To obtain the acceleration due to motion with respect to the Earth, this "gravity offset" must be subtracted and corrections made for effects caused by the Earth's rotation relative to the inertial frame. The reason for the appearance of a gravitational offset is Einstein's equivalence principle, which states that the effects of gravity on an object are indistinguishable from acceleration; when held fixed in a gravitational field by, for example, applying a ground reaction force or an equivalent upward thrust, the reference frame for an accelerometer accelerates upwards with respect to a free-falling reference frame. The effects of this acceleration are indistinguishable from any other acceleration experienced by the instrument, so that an accelerometer cannot detect the difference between sitting in a rocket on the launch pad, being in the same rocket in deep space while it uses its engines to accelerate at 1 g. For similar reasons, an accelerometer will read zero during any type of free fall.
This includes use in a coasting spaceship in deep space far from any mass, a spaceship orbiting the Earth, an airplane in a parabolic "zero-g" arc, or any free-fall in vacuum. Another example is free-fall at a sufficiently high altitude that atmospheric effects can be neglected; however this does not include a fall in which air resistance produces drag forces that reduce the acceleration, until constant terminal velocity is reached. At terminal velocity the accelerometer will indicate 1 g acceleration upwards. For the same reason a skydiver, upon reaching terminal velocity, does not feel as though he or she were in "free-fall", but rather experiences a feeling similar to being supported on a "bed" of uprushing air. Acceleration is quantified in the SI unit metres per second per second, in the cgs unit gal, or popularly in terms of standard gravity. For the practical purpose of finding the acceleration of objects with respect to the Earth, such as for use in an inertial navigation system, a knowledge of local gravity is required.
This can be obtained either by calibrating the device at rest, or from a known model of gravity at the approximate current position. Conceptually, an accelerometer behaves as a damped mass on a spring; when the accelerometer experiences an acceleration, the mass is displaced to the point that the spring is able to accelerate the mass at the same rate as the casing. The displacement is measured to give the acceleration. In commercial devices, piezoelectric and capacitive components are used to convert the mechanical motion into an electrical signal. Piezoelectric accelerometers rely on single crystals, they are unmatched in terms of their upper frequency range, low packaged weight and high temperature range. Piezoresistive accelerometers are preferred in high shock applications. Capacitive accelerometers use a silicon micro-machined sensing element, their performance is superior in the low frequency range and they can be operated in servo mode to achieve high stability and linearity. Modern accelerometers are small micro electro-mechanical systems, are indeed the simplest MEMS devices possible
Sony Corporation is a Japanese multinational conglomerate corporation headquartered in Kōnan, Tokyo. Its diversified business includes consumer and professional electronics, gaming and financial services; the company owns the largest music entertainment business in the world, the largest video game console business and one of the largest video game publishing businesses, is one of the leading manufacturers of electronic products for the consumer and professional markets, a leading player in the film and television entertainment industry. Sony was ranked 97th on the 2018 Fortune Global 500 list. Sony Corporation is the electronics business unit and the parent company of the Sony Group, engaged in business through its four operating components: electronics, motion pictures and financial services; these make Sony one of the most comprehensive entertainment companies in the world. The group consists of Sony Corporation, Sony Pictures, Sony Mobile, Sony Interactive Entertainment, Sony Music, Sony/ATV Music Publishing, Sony Financial Holdings, others.
Sony is among the semiconductor sales leaders and since 2015, the fifth-largest television manufacturer in the world after Samsung Electronics, LG Electronics, TCL and Hisense. The company's current slogan is Be Moved, their former slogans were The One and Only, It's like.no.other and make.believe. Sony has a weak tie to the Sumitomo Mitsui Financial Group corporate group, the successor to the Mitsui group. Sony began in the wake of World War II. In 1946, Masaru Ibuka started an electronics shop in a department store building in Tokyo; the company started with a total of eight employees. In May 1946, Ibuka was joined by Akio Morita to establish a company called Tokyo Tsushin Kogyo; the company built Japan's first tape recorder, called the Type-G. In 1958, the company changed its name to "Sony"; when Tokyo Tsushin Kogyo was looking for a romanized name to use to market themselves, they considered using their initials, TTK. The primary reason they did not is that the railway company Tokyo Kyuko was known as TTK.
The company used the acronym "Totsuko" in Japan, but during his visit to the United States, Morita discovered that Americans had trouble pronouncing that name. Another early name, tried out for a while was "Tokyo Teletech" until Akio Morita discovered that there was an American company using Teletech as a brand name; the name "Sony" was chosen for the brand as a mix of two words: one was the Latin word "sonus", the root of sonic and sound, the other was "sonny", a common slang term used in 1950s America to call a young boy. In 1950s Japan, "sonny boys" was a loan word in Japanese, which connoted smart and presentable young men, which Sony founders Akio Morita and Masaru Ibuka considered themselves to be; the first Sony-branded product, the TR-55 transistor radio, appeared in 1955 but the company name did not change to Sony until January 1958. At the time of the change, it was unusual for a Japanese company to use Roman letters to spell its name instead of writing it in kanji; the move was not without opposition: TTK's principal bank at the time, had strong feelings about the name.
They pushed for a name such as Sony Teletech. Akio Morita was firm, however. Both Ibuka and Mitsui Bank's chairman gave their approval. According to Schiffer, Sony's TR-63 radio "cracked open the U. S. market and launched the new industry of consumer microelectronics." By the mid-1950s, American teens had begun buying portable transistor radios in huge numbers, helping to propel the fledgling industry from an estimated 100,000 units in 1955 to 5 million units by the end of 1968. Sony co-founder Akio Morita founded Sony Corporation of America in 1960. In the process, he was struck by the mobility of employees between American companies, unheard of in Japan at that time; when he returned to Japan, he encouraged experienced, middle-aged employees of other companies to reevaluate their careers and consider joining Sony. The company filled many positions in this manner, inspired other Japanese companies to do the same. Moreover, Sony played a major role in the development of Japan as a powerful exporter during the 1960s, 1970s and 1980s.
It helped to improve American perceptions of "made in Japan" products. Known for its production quality, Sony was able to charge above-market prices for its consumer electronics and resisted lowering prices. In 1971, Masaru Ibuka handed the position of president over to his co-founder Akio Morita. Sony began a life insurance company in one of its many peripheral businesses. Amid a global recession in the early 1980s, electronics sales dropped and the company was forced to cut prices. Sony's profits fell sharply. "It's over for Sony," one analyst concluded. "The company's best days are behind it." Around that time, Norio Ohga took up the role of president. He encouraged the development of the Compact Disc in the 1970s and 1980s, of the PlayStation in the early 1990s. Ohga went on to purchase CBS Records in 1988 and Columbia Pictures in 1989 expanding Sony's media presence. Ohga would succeed Morita as chief executive officer in 1989. Under the vision of co-founder Akio Morita and his successors, the company had aggressively expanded in
The gigabyte is a multiple of the unit byte for digital information. The prefix giga means 109 in the International System of Units. Therefore, one gigabyte is 1000000000bytes; the unit symbol for the gigabyte is GB. This definition is used in all contexts of science, engineering and many areas of computing, including hard drive, solid state drive, tape capacities, as well as data transmission speeds. However, the term is used in some fields of computer science and information technology to denote 1073741824 bytes for sizes of RAM; the use of gigabyte may thus be ambiguous. Hard disk capacities as described and marketed by drive manufacturers using the standard metric definition of the gigabyte, but when a 500-GB drive's capacity is displayed by, for example, Microsoft Windows, it is reported as 465 GB, using a binary interpretation. To address this ambiguity, the International System of Quantities standardizes the binary prefixes which denote a series of integer powers of 1024. With these prefixes, a memory module, labeled as having the size 1GB has one gibibyte of storage capacity.
The term gigabyte is used to mean either 10003 bytes or 10243 bytes. The latter binary usage originated as compromise technical jargon for byte multiples that needed to be expressed in a power of 2, but lacked a convenient name; as 1024 is 1000 corresponding to SI multiples, it was used for binary multiples as well. In 1998 the International Electrotechnical Commission published standards for binary prefixes, requiring that the gigabyte denote 10003 bytes and gibibyte denote 10243 bytes. By the end of 2007, the IEC Standard had been adopted by the IEEE, EU, NIST, in 2009 it was incorporated in the International System of Quantities; the term gigabyte continues to be used with the following two different meanings: 1 GB = 1000000000 bytes Based on powers of 10, this definition uses the prefix giga- as defined in the International System of Units. This is the recommended definition by the International Electrotechnical Commission; this definition is used in networking contexts and most storage media hard drives, flash-based storage, DVDs, is consistent with the other uses of the SI prefix in computing, such as CPU clock speeds or measures of performance.
The file manager of Mac OS X version 10.6 and versions are a notable example of this usage in software, which report files sizes in decimal units. 1 GiB = 1073741824 bytes. The binary definition uses powers of the base 2, as does the architectural principle of binary computers; this usage is promulgated by some operating systems, such as Microsoft Windows in reference to computer memory. This definition is synonymous with the unambiguous unit gibibyte. Since the first disk drive, the IBM 350, disk drive manufacturers expressed hard drive capacities using decimal prefixes. With the advent of gigabyte-range drive capacities, manufacturers based most consumer hard drive capacities in certain size classes expressed in decimal gigabytes, such as "500 GB"; the exact capacity of a given drive model is slightly larger than the class designation. All manufacturers of hard disk drives and flash-memory disk devices continue to define one gigabyte as 1000000000bytes, displayed on the packaging; some operating systems such as OS X express hard drive capacity or file size using decimal multipliers, while others such as Microsoft Windows report size using binary multipliers.
This discrepancy causes confusion, as a disk with an advertised capacity of, for example, 400 GB might be reported by the operating system as 372 GB, meaning 372 GiB. The JEDEC memory standards use IEEE 100 nomenclature; the difference between units based on decimal and binary prefixes increases as a semi-logarithmic function—for example, the decimal kilobyte value is nearly 98% of the kibibyte, a megabyte is under 96% of a mebibyte, a gigabyte is just over 93% of a gibibyte value. This means that a 300 GB hard disk might be indicated variously as 300 GB, 279 GB or 279 GiB, depending on the operating system; as storage sizes increase and larger units are used, these differences become more pronounced. Some legal challenges have been waged over this confusion such as a lawsuit against drive manufacturer Western Digital. Western Digital settled the challenge and added explicit disclaimers to products that the usable capacity may differ from the advertised capacity. Seagate was sued on similar grounds and settled.
Because of its physical design, the capacity of modern computer random access memory devices, such as DIMM modules, is always a multiple of a power of 1024. It is thus convenient to use prefixes denoting powers of 1024, known as binary prefixes, in describing them. For example, a memory capacity of 1073741824bytes is conveniently expressed as 1 GiB rather than as 1.074 GB. The former specification is, however quoted as "1 GB" when applied to random access memory. Software allocates memory in varying degrees of granularity as needed to fulfill data structure requirements and binary multiples are not required. Other computer capacities and rates, like storage hardware size, data transfer rates, clock speeds, operations per second, etc. do not depend on an inherent base, are presented in decimal units. For example, the manufacturer of a "300 GB" hard drive is claiming a capacity of 300000000000bytes, not 300x10243 bytes. One hour of SDTV video at 2.2 Mbit/s is 1 GB. Seven minutes of HDTV video at 19.39 Mbit/s is 1
Memory is the faculty of the brain by which information is encoded and retrieved when needed. Memory is vital to experiences, it is the retention of information over time for the purpose of influencing future action. If we could not remember past events, we could not learn or develop language, relationships, or personal identity. Memory is understood as an informational processing system with explicit and implicit functioning, made up of a sensory processor, short-term memory, long-term memory; this can be related to the neuron. The sensory processor allows information from the outside world to be sensed in the form of chemical and physical stimuli and attended to various levels of focus and intent. Working memory serves as an encoding and retrieval processor. Information in the form of stimuli is encoded in accordance with explicit or implicit functions by the working memory processor; the working memory retrieves information from stored material. The function of long-term memory is to store data through various categorical models or systems.
Explicit and implicit functions of memory are known as declarative and non-declarative systems. These systems lack thereof. Declarative, or explicit, memory is the conscious recollection of data. Under declarative memory resides episodic memory. Semantic memory refers to memory, encoded with specific meaning, while episodic memory refers to information, encoded along a spatial and temporal plane. Declarative memory is the primary process thought of when referencing memory. Non-declarative, or implicit, memory is the unconscious recollection of information. An example of a non-declarative process would be the unconscious learning or retrieval of information by way of procedural memory, or a priming phenomenon. Priming is the process of subliminally arousing specific responses from memory and shows that not all memory is consciously activated, whereas procedural memory is the slow and gradual learning of skills that occurs without conscious attention to learning. Memory is not a perfect processor, is affected by many factors.
The ways by which information is encoded and retrieved can all be corrupted. The amount of attention given new stimuli can diminish the amount of information that becomes encoded for storage; the storage process can become corrupted by physical damage to areas of the brain that are associated with memory storage, such as the hippocampus. The retrieval of information from long-term memory can be disrupted because of decay within long-term memory. Normal functioning, decay over time, brain damage all affect the accuracy and capacity of the memory. Memory loss is described as forgetfulness or amnesia. Sensory memory holds sensory information less than one second; the ability to look at an item and remember what it looked like with just a split second of observation, or memorization, is the example of sensory memory. It is an automatic response. With short presentations, participants report that they seem to "see" more than they can report; the first experiments exploring this form of sensory memory were conducted by George Sperling using the "partial report paradigm".
Subjects were presented with a grid of 12 letters, arranged into three rows of four. After a brief presentation, subjects were played either a high, medium or low tone, cuing them which of the rows to report. Based on these partial report experiments, Sperling was able to show that the capacity of sensory memory was 12 items, but that it degraded quickly; because this form of memory degrades so participants would see the display but be unable to report all of the items before they decayed. This type of memory cannot be prolonged via rehearsal. Three types of sensory memories exist. Iconic memory is a fast decaying store of visual information. Echoic memory is a fast decaying store of auditory information, another type of sensory memory that stores sounds that have been perceived for short durations. Haptic memory is a type of sensory memory. Short-term memory is known as working memory. Short-term memory allows recall for a period of several seconds to a minute without rehearsal, its capacity is very limited: George A. Miller, when working at Bell Laboratories, conducted experiments showing that the store of short-term memory was 7±2 items.
Modern estimates of the capacity of short-term memory are lower of the order of 4–5 items. For example, in recalling a ten-digit telephone number, a person could chunk the digits into three groups: first, the area code a three-digit chunk and lastly a four-digit chunk; this method of remembering telephone numbers is far more effective than attempting to remember a string of 10 digits. This may be reflected in some countries in the tendency to display telephone numbers as several chunks of two to four numbers. Short-term memory is believed to rely on an acoustic code for storing information, to a lesser extent a visual code. Conrad found that test subjects had more difficulty recalling collections of letters that were acoustically similar (e.g. E
Robotics is an interdisciplinary branch of engineering and science that includes mechanical engineering, electronic engineering, information engineering, computer science, others. Robotics deals with the design, construction and use of robots, as well as computer systems for their control, sensory feedback, information processing; these technologies are used to develop machines that can substitute for humans and replicate human actions. Robots can be used in many situations and for lots of purposes, but today many are used in dangerous environments, manufacturing processes, or where humans cannot survive. Robots can take on any form but some are made to resemble humans in appearance; this is said to help in the acceptance of a robot in certain replicative behaviors performed by people. Such robots attempt to replicate walking, speech and anything a human can do. Many of today's robots are inspired by nature; the concept of creating machines that can operate autonomously dates back to classical times, but research into the functionality and potential uses of robots did not grow until the 20th century.
Throughout history, it has been assumed by various scholars, inventors and technicians that robots will one day be able to mimic human behavior and manage tasks in a human-like fashion. Today, robotics is a growing field, as technological advances continue. Many robots are built to do jobs that are hazardous to people such as defusing bombs, finding survivors in unstable ruins, exploring mines and shipwrecks. Robotics is used in STEM as a teaching aid; the advent of nanorobots, microscopic robots that can be injected into the human body, could revolutionize medicine and human health. Robotics is a branch of engineering that involves the conception, design and operation of robots; this field overlaps with electronics, computer science, artificial intelligence, mechatronics and bioengineering. The word robotics was derived from the word robot, introduced to the public by Czech writer Karel Čapek in his play R. U. R., published in 1920. The word robot comes from the Slavic word robota; the play begins in a factory that makes artificial people called robots, creatures who can be mistaken for humans – similar to the modern ideas of androids.
Karel Čapek himself did not coin the word. He wrote a short letter in reference to an etymology in the Oxford English Dictionary in which he named his brother Josef Čapek as its actual originator. According to the Oxford English Dictionary, the word robotics was first used in print by Isaac Asimov, in his science fiction short story "Liar!", published in May 1941 in Astounding Science Fiction. Asimov was unaware. In some of Asimov's other works, he states that the first use of the word robotics was in his short story Runaround, where he introduced his concept of The Three Laws of Robotics. However, the original publication of "Liar!" Predates that of "Runaround" by ten months, so the former is cited as the word's origin. In 1948, Norbert Wiener formulated the principles of the basis of practical robotics. Autonomous only appeared in the second half of the 20th century; the first digitally operated and programmable robot, the Unimate, was installed in 1961 to lift hot pieces of metal from a die casting machine and stack them.
Commercial and industrial robots are widespread today and used to perform jobs more cheaply and more reliably, than humans. They are employed in some jobs which are too dirty, dangerous, or dull to be suitable for humans. Robots are used in manufacturing, assembly and packaging, transport and space exploration, weaponry, laboratory research and the mass production of consumer and industrial goods. There are many types of robots. For example, a robot designed to travel across heavy dirt or mud, might use caterpillar tracks; the mechanical aspect is the creator's solution to completing the assigned task and dealing with the physics of the environment around it. Form follows function. Robots have electrical components. For example, the robot with caterpillar tracks would need some kind of power to move the tracker treads; that power comes in the form of electricity, which will have to travel through a wire and originate from a battery, a basic electrical circuit. Petrol powered machines that get their power from petrol still require an electric current to start the combustion process, why most petrol powered machines like cars, have batteries.
The electrical aspect of robots is used for movement and operation (robots need some level of electrical energy supplied to their motors and sensors in order to activate and perform b