What is EMC energy pool
Mine pool refers to:
as the computing level of the whole bitcoin network continues to rise exponentially, a single device or a small amount of computing power can not get the block reward provided by the bitcoin network on the bitcoin network
after the computing power of the whole network has been improved to a certain extent, the low probability of getting rewards has prompted some geeks on "bitcoin talk" to develop a method that can combine a small amount of computing power and operate jointly, and the website established in this way is called "mine pool"
extended data:
the existence of the mine pool reces the difficulty of bitcoin and other virtual digital currency mining, reces the mining threshold, and truly realizes the bitcoin mining concept that everyone can participate in
but its disadvantages are also very obvious, because computing power is connected to the mine pool. As a mine pool, it will have huge computing power resources. In the bitcoin world, computing power represents the bookkeeping right, and computing power is everything. If the computing power of a single mine pool reaches more than 50%, it will be easy to launch 51% attacks against virtual digital currencies such as bitcoin, The consequences are very terrible:
the mine pool can make the mine pool with 49% of the remaining computing power have no harvest, instantly quit the competition and go bankrupt. The mine pool's computing power exceeds 50%. If 51% attack is launched, it will easily occupy all the effective computing power of the whole network
u-coin can be recharged by voice, mobile phone, online banking, SMS, broadband, etc
by using the u-coin, you can recharge all kinds of game cards on the Internet, which is convenient, affordable and more secure.
Electromagnetic compatibility (EMC) refers to the ability of equipment or system to meet the requirements in its electromagnetic environment and not proce unbearable electromagnetic interference to any equipment in its environment
With the development of modern science and technology, the number and types of electrical and electronic equipment are increasing, which makes the electromagnetic environment increasingly complex. In this complex electromagnetic environment, how to rece the mutual electromagnetic disturbance and make all kinds of equipment work normally is an urgent problem to be solved; On the other hand, the bad electromagnetic environment will have a bad impact on human and ecology
extended data:
EMC includes two requirements: on the one hand, it means that the electromagnetic interference generated by the equipment to the environment in the normal operation process cannot exceed a certain limit value; On the other hand, it means that the instrument has a certain degree of immunity to the electromagnetic interference existing in the environment, that is, electromagnetic sensitivity
in recent years, with the wide application of high sensitive electronic technology in medical electrical equipment and the rapid development of new communication technologies, such as personal communication system and cellular telephone, in various fields of social life; Medical electrical equipment not only emits electromagnetic energy, which affects the radio communication business and the work of other surrounding equipment, but also may be interfered by electromagnetic energy emission from surrounding equipment such as communication equipment in its application environment, causing harm to patients
filter connector is often of great help to the EMC performance of procts, but its cost is relatively high. Generally, when the problem can be solved by using on-board filtering, cable shielding and other methods, filter connector is not used. Filter connectors are usually used in some special situations, such as strict military standard requirements, small batch applications in harsh instrial environment and some special situations (such as structure size restrictions)
the research of EMC theory and technology in China started relatively late, and its development in the medical field only started in the 1990s. In 1995, China issued GB 9706.1-1995 General requirements for safety of medical electrical equipment. It was not until April 5, 2005 that the former State Food and Drug Administration issued the mandatory instry standard for medical devices YY0505-2005 Medical electrical equipment Part 1-2: General requirements for Safety - parallel standards: electromagnetic compatibility - Requirements and tests
References: EMC network
electromagnetic environment
the sum of all electromagnetic phenomena existing in a given place
electromagnetic disturbance
any electromagnetic phenomenon that may cause performance degradation of devices, equipment or systems or damage to living or non living substances
electromagnetic interference (EMI)
the performance degradation of equipment, transmission channel or system caused by electromagnetic interference
radiated emission (RE) and concted emission (CE)
re: useful or unwanted electromagnetic energy transmitted through space. CE: electromagnetic emission transmitted along power supply or signal line
electromagnetic susceptibility (EMS)
the undesirable response of equipment exposed to electromagnetic environment. Radiation sensitivity CS and conction sensitivity CS
transient
a physical quantity or phenomenon that changes between two adjacent states, and its change time is less than the time scale concerned
with the development of modern science and technology, the number and types of electrical and electronic equipment are increasing, which makes the electromagnetic environment increasingly complex. In this complex electromagnetic environment, how to rece the mutual electromagnetic disturbance and make all kinds of equipment work normally is an urgent problem to be solved; On the other hand, the bad electromagnetic environment will have a bad impact on human and ecology
with the development of electrical and electronic technology, the popularization and electronization of household appliances, the development of radio and television, posts and telecommunications and computer networks, and the increasingly complex and deteriorating electromagnetic environment, the electromagnetic compatibility (EMC, EMI and EMS) of electrical and electronic procts has been paid more and more attention by governments and manufacturers. Electromagnetic compatibility (EMC) of electronic and electrical procts is a very important quality index, which is not only related to the reliability and safety of the proct itself, but also may affect the normal work of other equipment and systems, as well as the protection of electromagnetic environment
in order to standardize the EMC of electronic procts, all developed countries and some developing countries have formulated EMC standards. EMC standard is the basic requirement for procts to work normally in the actual electromagnetic environment. That is to say, even if the proct meets the EMC standard, interference may occur in actual use. Most of the national standards are based on the International Electrotechnical Commission (IEC) standards
EMC includes two requirements: on the one hand, the electromagnetic interference generated by the equipment to the environment in the normal operation process should not exceed a certain limit value; On the other hand, it means that the instrument has a certain degree of immunity to the electromagnetic interference existing in the environment, that is, electromagnetic sensitivity
in recent years, with the wide application of high sensitive electronic technology in medical electrical equipment and the rapid development of new communication technologies, such as personal communication system, cellular phone, etc., in various fields of social life; Medical electrical equipment not only emits electromagnetic energy, which affects the radio communication business and the work of other surrounding equipment, but also may be interfered by electromagnetic energy emission from surrounding equipment such as communication equipment in its application environment, causing harm to patients.
in recent years, with the wide application of high sensitive electronic technology in medical electrical equipment and the rapid development of new communication technologies, such as personal communication system, cellular phone, etc., in various fields of social life; Medical electrical equipment not only emits electromagnetic energy, which affects the radio communication business and the work of other surrounding equipment, but also may be interfered by electromagnetic energy emission from surrounding equipment such as communication equipment in its application environment, causing harm to patients. Electromagnetic compatibility (EMC) of medical electrical equipment has been paid more and more attention in many countries because it involves public health and safety. The necessity of formulating EMC standards for medical electrical equipment and medical electrical system has become a common understanding
in order to standardize the electromagnetic compatibility of electronic procts, all developed countries and some developing countries have formulated electromagnetic capacitance standards. EMC standard is the basic requirement for procts to work normally in the actual electromagnetic environment. The reason why it is called the basic requirement is that the proct meets the electromagnetic capacitance standard in time, and the interference problem may occur in actual use. Most of the national standards are based on the International Electrotechnical Commission (IEC) standards
IEC has two parallel organizations responsible for formulating EMC standards, namely CISPR (International Special Committee on radio interference) and TC77 (Technical Committee 77). CISPR was founded in 1934, and now has seven branches: branch a (radio interference measurement methods and statistical methods), branch B (radio interference of radio frequency equipment in engineering, science and medicine), branch C (radio interference of power line, high voltage equipment and electric traction system), branch D (radio interference of motor vehicle and internal combustion engine), branch e (interference characteristics of wireless receiving equipment), branch C (radio interference of power line, high voltage equipment and electric traction system) Branch f (radio interference of household appliances, electric tools, lighting equipment and similar electrical appliances), branch g (radio interference of information equipment). TC77 was founded in 1981 and has three branches: sc77a (low frequency phenomenon), sc77b (high frequency phenomenon) and sc77c (immunity to high altitude nuclear electromagnetic pulse)
the EMC standards of China's procts are based on CISPR and IEC standards, and 57 of them have been published
EMC standards are divided into basic standards, general standards, proct standards and special proct standards
basic standard: describes EMC phenomenon, specifies EMC test methods and equipment, and defines the level and performance criteria. The basic standard does not involve specific procts
Proct Standards: EMC testing standards for a certain proct family. Basic standards are often quoted, but more detailed regulations are put forward according to the particularity of procts
General Standard: according to the use environment of equipment, when there is no specific proct class standard to follow, the general standard is used for EMC testing. In order to make the equipment function safe and normal, we should also meet the requirements of these standards
although there are many EMC standard documents and their contents are complex, the requirements for equipment are divided from the following aspects
two requirements: the EMC standard has two requirements for the equipment: one is that the equipment will not proce adverse electromagnetic interference to the outside world when it works, and the other is that it cannot be excessively sensitive to the external electromagnetic interference. The former is called interference emission (EMI) requirement, and the latter is called sensitivity (EMS) or immunity requirement
from the way of energy transmission: in order to find the requirements of these two aspects, we further divide them from the way of electromagnetic energy transmission equipment and incoming equipment, and there are concted interference and radiated interference. Concted interference means that the interference energy is transmitted in the form of current along the cable, while radiated interference means that the energy is transmitted in the form of electromagnetic wave. Because the EMC requirements of equipment can be divided into: concted emission, radiated emission, concted sensitivity (immunity), radiated sensitivity (immunity)
electrostatic discharge test is a special kind of test, and its interference to equipment may be concted or radiated, depending on the location of electrostatic discharge and the test method.
electromagnetic environment
the sum of all electromagnetic phenomena existing in a given place
electromagnetic disturbance
any electromagnetic phenomenon that may cause performance degradation of devices, equipment or systems or damage to living or non living substances
electromagnetic interference (EMI)
the performance degradation of equipment, transmission channel or system caused by electromagnetic interference
radiated emission (RE) and concted emission (CE)
re: useful or unwanted electromagnetic energy transmitted through space. CE: electromagnetic emission transmitted along power supply or signal line
electromagnetic susceptibility (EMS)
the undesirable response of equipment exposed to electromagnetic environment. Radiation sensitivity CS and conction sensitivity CS
transient
a physical quantity or phenomenon that changes between two adjacent states, and its change time is less than the time scale concerned