Ten Daily Electronic Common Sense-Section 23

What does extension mean?

Epitaxy refers to the growth of a film of the same single crystal material on a single crystal substrate.

What is the core of the photoelectric high sensor?

The core of the photoelectric high sensor is a photoelectric component consisting of four groups of light-emitting diodes and phototransistors.

What are the meanings of the network connected to things?

The providers and users of information gradually extend from people to physical entities, and between objects communicate and exchange information through the Internet of Things; physical entities are implemented through various wireless and/or wired, long-distance, and/or short-range communication networks. Interconnection, communication, and transmission processes do not require or require limited manual intervention.

What are the basic links of the augmented reality 3D helmet display?

• Virtual information display channel
• Real environment display channel
• Image fusion and display channel

The WirelessHART security system defines four keys. What is it?

1. When there is no network key, the public key is used to generate the MIC of the MAC layer.
2. The network key is shared by all network devices and used by the network devices to generate the MIC of the MAC layer.
3. The network access key is unique to each network device. When a device joins the network, the network access key is used by the network manager to authenticate the new device that is applying for network access.
4. The session key is created by the network manager. The session key is unique for the end-to-end connection between two network devices and is used to provide end-to-end encryption and data integrity services. Session keys can be further divided into unicast keys and broadcast keys. Unicast keys and broadcast keys are very difficult how to store and use random numbers (Nonce).

What are the classifications of the application?

1. Process monitoring program. Including switch state detection procedures, pulse detection procedures, analog circuit detection procedures, and control console service procedures. This kind of program is set up to monitor and control the production process, and there must be corresponding hardware equipment to cooperate with it.
2. Data processing program. The function of this type of program is to process or transform the data input to the computer or the control quantity output by the computer. Including digital filtering procedures, linearization processing procedures, engineering quantity conversion procedures, etc.
3. Control algorithm and actuator control program. It includes the PID control algorithm, look-up table method, and other control procedures. These programs are set up so that the computer can control them according to certain rules.
4. Fault self-diagnosis and other general subroutines.

How does the inductive synchronizer measure?

The inductive synchronizer performs displacement measurement by displacement resulting in a change in the mutual inductance between the two windings.

What technical requirements do the automotive MCU application systems need to meet while implementing the measurement and control functions?

• The automotive microcontroller application system is different from the general-purpose computer system. General-purpose computer systems are mainly used for data processing, requiring large storage capacity, fast running speed, and strong versatility. The application system of the automobile single-chip microcomputer mainly realizes the detection of various signals and the control of each component. The function is relatively simple and does not require strong versatility. While realizing the measurement and control function, the automotive MCU application system must also meet the following technical requirements:
  1. High reliability and emergency backup function If the automotive MCU application system fails, it may cause heavy losses. Therefore, reliability is very important to the application system of automobile single-chip microcomputers. Moreover, once the automobile single-chip microcomputer system fails, there is also an emergency backup system that can temporarily replace the automobile single-chip microcomputer to maintain the operation of the automobile.
  2. Adapt to the harsh environment of automobile operation The automobile single-chip microcomputer application system is assembled on the automobile, and the operating environment of the automobile is very different, and sometimes the environmental conditions are very harsh, such as extreme temperature differences, complex climate, harsh road conditions, and corrosive substances. influence, etc. Electromagnetic wave interference and voltage fluctuations generated by various electrical equipment will have a certain impact on the normal operation of the automotive microcontroller system. Therefore, to make the automotive single-chip microcomputer system work reliably and without failure, the following requirements must be met:
     • The temperature resistance range is -40 ~ 125 0C.
     • Anti-electromagnetic interference is not easily affected by external radiation (such as mobile wireless phones); there is no radiation of electromagnetic interference itself.
     • Vibration resistance.
     • Resistant to moisture and humidity.
     • Resistant to aggressive liquids, such as engine oil and smoke.
     • lightweight.
     • low production cost.
     • Reliable installation.
  3. It has perfect input/output channels and real-time control capabilities. To detect and control the running process of the automobile, it is necessary to transmit a large amount of data and various types of signals. Therefore, the automobile single-chip microcomputer system is required to have relatively complete analog and digital inputs. /output channel. The control signal of the automobile running process is real-time, and the single-chip microcomputer is required to have a fast enough response speed to the change of the input signal and can process and change the control signal in time. Therefore, the automobile single-chip microcomputer system is required to have a relatively complete interrupt processing capability.
  4. Easy to operate and maintain The single-chip microcomputer system of the car is installed on the car, and the users are generally not professional computer personnel, so the design of the operating system and the signal control system should be simple and clear, and easy to operate. Once a fault occurs, the cause can be identified in time and eliminated quickly.
  5. Has certain scalability According to the possible changes in the process of automobile production and automobile operation, the automotive single-chip microcomputer system should have scalability in terms of input/output ports, memory, and so on. And should set aside the data interface, it is convenient for the maintenance personnel to use the fault code reader to read the fault code from the single-chip microcomputer system, to provide convenience for maintenance.
  6. Have a relatively complete software system A relatively complete software system should include functions such as monitoring, management, control, calculation, detection, self-diagnosis, and communication, and should also have optimized control algorithms and control logic, high real-time performance And the ability to resist electromagnetic interference, from the software to ensure the reliability of the automotive microcontroller application system.

What are the types of positioning problems in wireless sensor networks?

One is the positioning of the wireless sensor network to its sensor nodes, and the other is the positioning of the wireless sensor network to external targets.

What is personalization?

The memory cells in the EzPROM are divided into several zones according to their roles. Personalization refers to the process by which an IC card is issued to an individual by a publisher.