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    What is on the fixed length and the slider winding?

    There are three sets of planar windings of thick, medium and thin on the fixed-length and sliding-rule windings.

    What is the central processor?

    Processor: The processor (Center Processing Unit, referred to as CPU) is the core component of the mobile phone. The microprocessor in the mobile phone is similar to the central processing unit (CPU) in the computer. It is the control center system of the whole mobile phone, and also the control core of the logic part.
    The microprocessor achieves the purpose of overall monitoring of the mobile phone by running the software in the memory and calling the database in the memory. All the data to be processed must be completed by the CPU, and the management of various parts of the mobile phone is inseparable from the unified and coordinated command of the headquarters of the microprocessor.
    With the continuous improvement of integrated circuit production technology and process level, the functions of microprocessors in mobile phones are becoming more and more powerful. Such as integrating advanced digital signal processor (DSP) in the microprocessor and so on.
    The performance of the processor determines the performance of the entire mobile phone.
    Main frequency: Processor main frequency is an important technical parameter to measure the performance of mobile phone CPU. Almost all people use it as a reference value when purchasing. “Working frequency” is also called “main frequency”, the higher the frequency, the faster the execution speed of the instruction. The shorter the execution time of the instruction, the higher the ability and efficiency of information processing. What I want to say to beginners here is that the operating frequency of the processor does not completely determine its working performance, design methods, operating environment, etc. These are important factors for good or bad performance.
    At present, the main frequency of CPU used in mainstream mobile phones is 104MHz, 160MHZ, 200MHZ, 220MHz and 400MHz.

    What are the characteristics of the tag antenna?

    1. The physical size of the antenna is small: the physical size of the tag needs to be small enough so that it can be attached to the desired item. In the electronic tag, the area of the antenna is dominant, that is, the area of the electronic tag mainly depends on the area of its antenna. The physical size of the antenna is limited by the wavelength of the electromagnetic wave of its operating frequency. The higher the frequency, the shorter the wavelength of the electromagnetic wave, and the smaller the size of the antenna.
    2. In most cases, the electronic tag antenna is required to have omnidirectional or hemispherical coverage.
    3. High gain: It can provide the largest possible signal to the chip of the label.
    4. Good impedance matching: no matter what direction the tag is in, the polarization of the antenna can match the signal of the reader.、
    5. Low cost.

    In addition to high coherence, what are the advantages of HeNe lasers?

    • It is easy to realize single-mode operation, and the line width is very narrow, which can be as low as 1 kHz. This is more valuable for interferometric sensors;
    • The radiation density is very high, and the coupling efficiency with single-mode fiber is high. For example, a circular area HeNe laser with a diameter of 1 mm produces a typical output power of 1 mW with a divergence angle of about 1 mrad. Therefore, its corresponding single transverse mode radiation density is about 108 W/(sr.cm?), which can be coupled into single-mode fiber with high efficiency;
    • The noise is small, except for the plasma resonance frequency in the laser cavity. HeNe lasers are fairly quiet in the rest of the frequency band, with noise levels very close to flicker noise.

    What criteria does SA2 propose for NIMTC’s solution selection?

    If non-3GPP solutions can be used, non-3GPP solutions should be selected as much as possible.
    If a non-3GPP solution cannot be adopted, a solution that has no or little impact on the 3GPP system should be selected as much as possible.
    Only when the function of the existing 3GPP system must be modified to meet the requirements proposed by SAl, the solution that has an impact on the current 3GPP system is selected.

    What is the transformer protection TA disconnection criterion?

    • If zero-sequence current appears on the △ side of the transformer, it is judged that TA on this side is disconnected;
    • The Y side of the transformer, such as a common winding transformer. If the difference between the self-produced zero-sequence current and the zero-sequence current introduced by TA on the neutral point side of the transformer exceeds a certain value, it is determined that TA on this side is broken. Delayed alarm signal.

    The difference between electric valve and solenoid valve:

    Solenoid valve is that after the electromagnetic coil is energized, it generates magnetic attraction to overcome the pressure of the spring to drive the valve core to move, just an electromagnetic coil. The structure is simple, the price is cheap, and only the switch can be realized.
    The electric valve drives the valve stem through the motor to drive the valve core to move. The electric valve is divided into a shut-off valve and a regulating valve.
    The shut-off valve is a two-position work, that is, fully open and fully closed. The regulating valve is equipped with an electric valve positioner, and the valve is dynamically stabilized in one position through closed-loop adjustment.
    Uses of electric valves and solenoid valves:
    Solenoid valve: used for on-off control of liquid and gas pipelines, it is controlled by two-position DO. Generally used for the control of small pipelines.
    Electric valve: It is used for the analog quantity adjustment of the medium flow of liquid, gas and wind system pipelines, and it is controlled by AI. In the control of large valves and wind systems, electric valves can also be used for two-position switch control.
    Solenoid valve: It can only be used as a switch value, it is DO control, and it can only be used for small pipeline control. It is common in pipelines of DN50 and below, and rarely goes up.
    Electric valve: It can have AI feedback signal and can be controlled by DO or AO. It is more common in large pipelines and air valves.

    1. Switch form: The solenoid valve is driven by a coil, it can only be opened or closed, and the action time is short when switching. The electric valve is generally driven by a motor, and it takes a certain amount of time to simulate the opening or closing action, which can be adjusted.
    2. Working nature: The solenoid valve generally has a small flow coefficient and a small working pressure difference. For example, the flow coefficient of a general 25-caliber solenoid valve is much smaller than that of a 15-caliber electric ball valve. The drive of the solenoid valve is through the electromagnetic coil, which is relatively easy to be damaged by voltage shock. It is equivalent to the function of a switch, that is, on and off. Electric valves are generally driven by motors, which are more resistant to voltage shocks. Solenoid valves open and close quickly, and are generally used in places with small flow and low pressure, where high switching frequency is required, and electric valves are the opposite. The opening of the electric valve can be controlled, and the state is open, closed, half-open and half-closed, which can control the flow of the medium in the pipeline, but the solenoid valve cannot meet this requirement. Solenoid valves can generally be reset when power is off, and electric valves need to be equipped with a reset device for such a function.
    3. Applicable process: Solenoid valve is suitable for some special process requirements, such as leakage, special fluid medium, etc., and the price is more expensive. Electric valves are generally used for regulation, and there are also switches, such as: the end of the fan coil unit.

    What is a spin-on spin coating?

    The self-rotation method is a spin coating method in which the substrate is attracted and fixed on the rotating shaft of the motor by a decompression method.

    What is monocrystalline silicon?

    Monocrystalline silicon English name: Monocrystalline silicon. Molecular formula: Si single crystal of silicon.
    A crystal with a substantially complete lattice structure. Different directions have different properties, and it is a good semiconducting material. The purity requirement reaches 99.9999%, or even more than 99.9999999%.
    Used in the manufacture of semiconductor devices, solar cells, etc. It is drawn from high-purity polysilicon in a single crystal furnace. When the molten elemental silicon is solidified, the silicon atoms are arranged in the diamond lattice to form many crystal nuclei. If these crystal nuclei grow into grains with the same crystal plane orientation, these grains combine in parallel to crystallize into single crystal silicon.
    Single crystal silicon has the physical properties of a metalloid and has weak electrical conductivity. Its conductivity increases with the increase of temperature, and it has significant semi-conductivity.
    Ultrapure single crystal silicon is an intrinsic semiconductor. Doping a small amount of group IIIA elements, such as boron, in ultra-pure single crystal silicon can increase its electrical conductivity to form a p-type silicon semiconductor; if doping a small amount of group VA elements, such as phosphorus or arsenic, can also increase the electrical conductivity. An n-type silicon semiconductor is formed.
    The method of making single crystal silicon is usually to make polycrystalline silicon or amorphous silicon first, and then use Czochralski method or suspension zone melting method to grow rod-shaped single crystal silicon from the melt.
    Monocrystalline silicon is mainly used to make semiconductor components. Uses: It is the raw material for manufacturing semiconductor silicon devices, used to make high-power rectifiers, high-power transistors, diodes, switching devices, etc.
    Monocrystalline silicon is a relatively active non-metallic element, an important part of crystalline materials, and is at the forefront of the development of new materials. Its main uses are as semiconductor materials and the use of solar photovoltaic power generation, heating and so on.
    Because solar energy has many advantages such as cleanness, environmental protection, and convenience. In the past 30 years, solar energy utilization technology has made great progress in research and development, commercial production, and market development, and has become one of the emerging industries with rapid and stable development in the world.
    Monocrystalline silicon construction projects have a huge market and broad development space. The silicon element with a content of 25.8% in the earth’s crust provides an inexhaustible source for the production of monocrystalline silicon.
    In recent years, various crystal materials, especially high-tech value-added materials represented by monocrystalline silicon and their related high-tech industries have developed. Become the pillar of the contemporary information technology industry, and make the information industry the fastest growing leading industry in the global economic development.
    Monocrystalline silicon, as a high-tech resource with great potential and urgently needed to be developed and utilized, is attracting more and more attention and attention.

    What are the characteristics of a pneumatic detector?

    This sensor is characterized by high sensitivity and stable performance. But the response time is long, the structure is complex, and the strength is poor. For laboratory use only.


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