What is a Blu-ray drive？
The English name of the Blu-ray drive is: Blu-rayDisc, which is translated into Blu-ray in Chinese. It is the next-generation disc format for DVD discs.
The drive is what we usually call an optical drive, a device that reads information from a disc. Under the condition that humans have increasingly strict quality requirements for multimedia, it is used to store high-quality video and high-capacity data storage. Its current competitor is HDDVD, both of which are backed by different companies, and both want to become the standard specification.
The name Blu-ray comes from the laser wavelength 405 nanometers (nm) it uses, which happens to be the blue light in the spectrum, hence the name. (DVD uses a red light reader with a wavelength of 650nm, and CD uses a 780nm wavelength.) The Blu-ray Disc Alliance was originally planning to release products at the Consumer Electronics Show in January 2006. Later in the process of developing Blu-ray technology, Sony felt that it was necessary to take some additional measures to cooperate. So announced to postpone the release date of PLAYSTATION3 to November 2006. The relevant members of the Blu-ray Disc Alliance also postponed the release date of related products using Blu-ray technology to June 30, 2006 accordingly. Blu-ray is the next generation of optical drive technology.
The light from a DVD is red, and the light from a blue light is blue. The wavelengths are different, so it is called blue light. A Blu-ray disc can store 40GB-120GB, and its anti-piracy technology is better than DVD.
What is the drift of the sensor?
During the continuous use of the sensor, even if the input remains constant, the output will sometimes shift in one direction, which is called drift.
What is AC?
Alternating current is a current or voltage that changes in magnitude and direction over time. It is divided into sinusoidal alternating current and non-sinusoidal alternating current. Sinusoidal alternating current is widely used in production and life, while non-sinusoidal alternating current is widely used in electronic equipment.
What is the role of reactors in the power system?
The common reactors used in power systems are series reactors and shunt reactors.
The series reactor is mainly used to limit the short-circuit current, and it is also used in series or parallel with the capacitor in the filter to limit the high-order harmonics in the power grid.
Shunt reactors are used to absorb capacitive reactive power in the grid. For example, the high-voltage reactor in the 500kV power grid and the low-voltage reactor in the 500kV substation are used to absorb the reactive power of the line charging capacitor. The reactors in the 220kV, 110kV, 35kV, and 10kV power grids are used to absorb the charging capacitive reactive power of the cable lines. The operating voltage can be adjusted by adjusting the number of parallel reactors.
Ultra-high voltage shunt reactors have various functions to improve the operating conditions of reactive power in power systems, including:
1) When the large unit is paralleled with the system, reduce the power frequency steady-state voltage on the high-voltage bus, so that the generators can be paralleled at the same time.
2) Prevent the self-excitation resonance phenomenon that may occur in the generator with long lines.
3) When the neutral point of the reactor is used to pass the small reactance grounding device, the small reactor can also be used to compensate the phase-to-phase and phase-to-ground capacitance of the line to accelerate the automatic extinguishing of the submerged supply current, which is convenient for single-phase fast reclosing.
4) Capacitance effect on light no-load or light-load lines to reduce power frequency transient overvoltage.
5) Improve the voltage distribution on long transmission lines.
6) Make the reactive power in the line as balanced as possible at light load, prevent the unreasonable flow of reactive power, and reduce the power loss on the line at the same time.
HART supports multiple types of network communication services, including what?
- Request/Response: This is the direct communication between the host computer and a specified device. In this communication, the source device address and the destination device address are explicitly given. The content of requests and responses are given by specific HART commands.
- Issue of process data: Some HART commands are used to request process data and then issued in the form of command responses.
- The broadcast message uses the standard HART request/response type, but the target address uses the broadcast address.
- Block data transfer A pipeline is established between two network nodes to support the transmission of data in the form of a stream between them.
What does mutual inductance mean?
Mutual inductance If two coils are close to each other, part of the magnetic flux generated by the current in the first coil is linked with the second coil. When the current in the first coil changes, the magnetic flux linked with the second coil also changes, and an induced electromotive force is generated in the second coil. This phenomenon is called mutual inductance.
How to use the conversion method for programming?
The conversion method is to convert the relay circuit diagram into a ladder diagram inside the PLC with the same function as the original.
This equivalent conversion is an easy and quick way to program:
First, the original relay control system has been used and tested for a long time, and it has been proved that it can complete the control function required by the system;
Second, there are many similarities between the relay circuit diagram and the PLC ladder diagram in terms of representation and analysis methods, so it is convenient and quick to design the ladder diagram according to the relay circuit diagram;
Third, this design method generally does not need to change the control panel, maintains the external characteristics of the original system, and the operator does not need to change the long-term operation habits.
What is included in the micro pressure transmitter measurement line?
The measurement circuit of the micro pressure transmitter includes DC stabilized power supply, oscillator, phase-sensitive detection and indication.
What is the definition of network capacity?
Network capacity refers to the maximum number of packets that can be delivered from Alice to Bob in an average time, denoted by C. If no interference from adversaries is assumed, C is equal to the maximum flow of the network. In addition, it is the minimum cut from the source node to the destination node (for the multicast case, C is defined as the minimum value of the minimum cuts from the source node to all the destination nodes). The error probability refers to the probability that Bob cannot accurately recover Alice’s information.
The rate R is the average number of information symbols that can be passed from Alice to Bob per unit time step. If for any ∈1>0 and ∈2>0, there exists an encoding scheme that can encode packets of packet size n. If the rate is greater than or equal to R-∈2 and the error probability is less than or equal to ∈1, then the rate R is said to be achievable. Capacity in a given attack scenario refers to the maximum rate achievable in that scenario.
What is the function of the arithmetic unit?
The function of the operation part is to realize the arithmetic and logical operation of the data.
COMMENTS