As we all know, one of the advantages of LED is that it has a high photoelectric conversion efficiency, which is greatly improved compared with the traditional light source. However, due to the limitations of current technology development, the efficiency is still only 15-20%, which means as many as 80-85% of the energy is still converted into heat. Therefore, heat dissipation has always been an important challenge for LED lighting.
Mao Yuhai, a retired professor at Tsinghua University and a consultant at PAM in the United States, believes that the main challenge for LED cooling is high-power street lights and the heat dissipation of high-brightness lights in stadiums and stadiums. Because of the high power, the amount of heat required is also large, and it faces various hot and cold weather in the open air, which increases the difficulty of heat dissipation. The high-intensity spotlights in the theater are also one of the difficulties. In addition, because of its small size and high power, high-power PAR38 lamps require no electromagnetic interference and increase the difficulty of heat dissipation.
There are many types of LED thermal solutions, including aluminum heat sink fins, thermal plastic shells, fans, heat pipes, and surface radiation heat treatment. Among them, heat sinks and high-speed fans are currently the most common treatment. However, as the demand for light output in lighting applications continues to increase, the heat flux density of LED products continues to increase, and the amount of heat required to cool per unit time is also increasing. Therefore, Jin Hailin, head of technical support for Asia Pacific, Nuventix, points out that it is currently the largest. The challenge is how to reduce the increasing heat flux density.
Advanced technologies such as emerging piezoelectric ceramic fans and fanless fans have strong heat dissipation capabilities, but for applications such as LED lighting, such as size, power consumption, cost, structure, mass production, etc. Comprehensive consideration does not apply.
According to Jin Hailin, since the passive radiator is subject to limited heat exchange capacity, the amount of heat that can be taken away per unit time is very limited, so that the radiator used to cool the high-power LED module has to be made very heavy. Active heat dissipation (such as SynJet cooling solution) can overcome these shortcomings, quickly remove heat by forced high-efficiency heat dissipation of convection heat transfer, reduce the temperature of the LED chip , and at the same time reduce the volume and weight of the heat sink to better meet the requirements. The requirement for miniaturization of lighting design.
Digital currency transactions allow users to convert existing digital currencies into other digital currencies. The entire transaction does not involve any legal tender. Because of the relatively loose regulation, the mainstream digital currency trading platform also opened this function.Digital Asset Exchange (DAE) is a platform for matching transactions between digital currencies, digital currencies and legal currencies. It is the main place for encrypting the circulation and price determination of digital currency transactions.
Compared with traditional stock exchanges, digital asset trading platform not only matches transactions, but also plays the role of market maker and investment bank. The role of the market maker in the trading platform can increase the liquidity of the market, and the trading platform can earn the transaction price difference. The role of the investment bank of the trading platform is to provide services such as issuance and underwriting of digital currency, from which the trading platform collects money fees, or collects deposits in the form of community voting of the trading platform.
Currency Exchange,Digital Currency Exchange,Virtual Digital Currency Exchange,Display Currency Exchange
China youbi digital assets limited , https://www.ubcoinchina.com