Child posture reminderAuthor: Xu Songliang
1. Project Background ( 100-200words )
"You should sit up straight and write, or you will become nearsighted..." As a father of a nine-year-old child, I have...
When a signal is transmitted on a transmission line, if it encounters impedance discontinuity, signal reflection will occur. I want to know how the signal is reflected and why reflection occurs when t...
[i=s]This post was last edited by ohahaha on 2018-5-25 13:41[/i] [align=left][color=#000][font=微软雅黑][size=4]1. Q: My ALLEGRO is version 14.0, and I don't see the SUB DRAWING command after FILE-EXPORT....
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]
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]
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]
Experimental tasks
A DS18B20 is used to form a temperature measurement system. The temperature measurement accuracy reaches 0.1 degrees. The temperature range is between -20 degrees and +50 de...[Details]
In 2012, more than half of the cars in the European, Japanese and American car markets will be equipped with color displays, navigation systems, satellite communications and other in-vehicle infota...[Details]
At present, the traffic congestion in cities is quite serious. According to relevant news reports: In China, the traffic congestion has expanded from megacities such as Beijing, Shanghai, and Guangzho...[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
High-precision current source can provide high-precision current supply for precision instruments, and is suitable for automatic measurement tasks of various resistors in semico...[Details]
introduction
At present, measuring instruments are developing towards networking, and each individual embedded instrument will become a node on the Internet. This system realizes the network...[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]
introduction
LEDs continue to gain popularity in automotive applications, thanks to their long lifespan and the flexibility they offer for body styling and interior design. Some may be surpris...[Details]
Rated capacity refers to the maximum output power of the UPS (the product of voltage V and current A).
Usually, the UPS power supplies sold on the market are marked with "W" (watt) for smaller...[Details]
1 Battery technology determines the fate of energy vehicles
Regardless of whether new energy vehicles are hybrid or pure electric vehicles, they cannot do without the core technology of batter...[Details]
Direct digital frequency synthesis (DDS) has fast frequency switching and modulation capabilities and is widely used. However, when low power consumption and low cost are the main considerations, D...[Details]
For a long time, my country has implemented "community-style collective heating" for hot water heating, and settled accounts based on the heating area, regardless of whether the user uses heat. Thi...[Details]