The 11th Five-Year Plan for the Development of Science and Technology in the Information Industry and the Outline of the Medium- and Long-Term Plan for 2020PrefaceThe first 20 years of the 21st centur...
Does using mobile phones affect human health? The results of a recent mobile phone user study published in Denmark show that there is no direct correlation between using mobile phones and brain tumors...
[i=s] This post was last edited by dontium on 2015-1-23 11:42 [/i] Regarding the resistor noise power, I have always remembered the value KT[b]B[/b], but when I suddenly thought of calculating the noi...
Due to business needs, our company is in urgent need of recruiting software development engineers who are familiar with embedded C language, serial port development, LCD and keyboard applications. The...
Many programs have made this judgment. See how it is done on the Internet. [color=#000][/color] [p=24, null, left][color=#454545][backcolor=rgb(252, 248, 233)][font=tahoma, helvetica, arial][size=12px...
introduction
Since the beginning of the 21st century, the world of information has changed rapidly. Maybe a high-tech product will be released today and a better similar product will be releas...[Details]
1. Introduction
RFID (radio frequency identification) is a non-contact automatic identification technology that emerged in the 1990s. It uses the characteristics of radio frequency signal prop...[Details]
Analog engineers have traditionally struggled with complexity when designing power supplies that required multiple outputs, dynamic load sharing, hot-swap, or extensive fault-handling capabilities....[Details]
There are three types of mobile TV: one is based on analog TV broadcasting network, another is based on mobile communication network, and the other is based on digital broadcasting network. The f...[Details]
In public places such as schools, government agencies, factories and mines, as well as public corridors in residential areas, the phenomenon of long-burning lights is very common, which causes a h...[Details]
The reason for the light decay of white LEDs: the decline of phosphor performance
So far, the rapid decline of the luminous performance of white light LEDs, especially low-power white light LE...[Details]
Electronic systems are located at different points on the automotive power bus and therefore often need to operate under very stringent power requirements. These include load dump, cold crank, very lo...[Details]
Battery life is critical for portable applications. For applications such as smoke detectors, security devices, and thermostats, factory-installed batteries need to last for more than 10 years. The...[Details]
1. Introduction
Testing the temperature of steel billets before rolling is an important measure to ensure the quality of steel. Traditional manual testing is difficult to ensure product qu...[Details]
Toyohashi University of Technology demonstrated electric field coupled wireless power supply technology using life-size car tires and roads at the wireless technology exhibition "Wireless Technolog...[Details]
1 Introduction
There have been many studies on the detection and protection of power grid short circuit and line fault. The short circuit, overload and overvoltage protectors on the market have ...[Details]
Single-chip microcomputers are widely used because of their small size, powerful functions and low price. This article introduces the method of designing a micro electronic piano using the AT89C51 sin...[Details]
1. When the slip speed regulating motor is undergoing frequency conversion and energy saving transformation, the original excitation box (referred to as the speed regulating box) and the original s...[Details]
Since the late 1990s, with the demand for higher system efficiency and lower power consumption, the technological update of telecommunications and data communication equipment has promoted the deve...[Details]
0 Introduction
Ultrasonic waves
are mechanical waves with a frequency of more than 20KHz, and the propagation speed in the air is about 340 m/s (at 20°C). Ultrasonic waves can be gene...[Details]