Đại kiện tướng cờ vua Dorsa Derakhshani người Ba Tư (Iran), từng đoạt 3 huy chương vàng giải cờ vua trẻ châu Á năm 14 tuổi. Vì không đội khăn trùm đầu hijab nên Derakhshani bị Ba Tư cấm chơi, cô chuyển sang chơi cho đội tuyển Hoa Kỳ.
“Nếu như hoa biết chiều nay rụng
Âu cũng vui mà nở sáng nay” – Thắp tạ – Tô Thùy Yên
Âm thanh được tạo nên nhờ những sóng dao động cơ học; đại lượng đo dao động là tần số. Tai của con người có thể nghe được âm thanh trong khoảng tần số từ 20Hz đến 20kHz (tần số dao động từ 20 đến 20.000 lần/giây), những tần số thấp hơn 20Hz được gọi là hạ âm và tần số cao hơn 20kHz được gọi là siêu âm.
Để dễ phân biệt, người ta thường chia dải tần số âm thanh mà tai người nghe được ra làm 3 loại: âm bass, mid, treble (âm trầm, âm trung, âm cao).
Mid làm người nghe thấy say mê với giai điệu của lời ca, tiếng nhạc; Bass khiến người nghe hưng phấn; còn Treble với những thanh âm nhấn nhá làm người ta thích thú.
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USB-C chargers are turning up on many different devices, so it’s not strictly relegated to laptops. Newer phones use USB-C charging, car chargers may come with USB-C ports, and portable chargers (discussed more below) can have USB-C options. But laptops tend to have USB-C more frequently than other devices, at least for now.
USB-C is a universal charging standard. That means that, technically, it doesn’t matter what USB-C charger you use — it should be able to power up a laptop with a USB-C charging port and power bank. In the real world, this is taking a while to come true. Today the majority of laptop USB-C chargers are interchangeable, but it’s not guaranteed.
Some laptops come with USB-C ports that don’t charge. This is most common on laptops that come with their own proprietary charger — although a number of laptops can be charged either way, only the propriety charger tends to power up a laptop more quickly. The Samsung Notebook 9 is an example of that, as is the 2019 HP Envy 13. If you’re not sure exactly how to charge your laptop, check the manufacturer’s website, or look up a review of the system here at Digital Trends.
USB Power Delivery is a power transfer standard introduced alongside USB-C. It is an open standard maintained by the USB Implementors Forum, as is USB-C and other USB standards. All USB PD is USB-C, but not all USB-C is USB PD.
There are three versions of the standard:
USB Power Delivery 1.0
USB Power Delivery 2.0
USB Power Delivery 3.0
USB Power Delivery allows for increased power levels. Up to 100W, enough to power a 15-inch gaming laptop. Power flow is also bi-directional. The same port can give or take power, with the connection determining what to do.
The dream of many was that USB PD would become the dominant way to charge all future USB-C devices. As an open standard, no one brand would control the market. And one charger (with enough output) could power all your devices. But this hasn’t been the case to date. And whether it’ll happen in the future is up to specific companies, who do not have a stake in the USB-IF.
Laptops that rely entirely on USB-C, meanwhile, might not charge with just any charger. PCWorld, in its testing, found that HP’s Spectre x2 wouldn’t charge with any USB-C charger besides its own. HP said that that was intentional because a bad charger could damage the device or cause it to malfunction. Other devices, like the Apple MacBook Pro, don’t have such tight restrictions — a new USB-C authentication system could help with this issue in the near future.
While we haven’t personally heard of any damage from using a USB-C charger other than the one that came with your laptop, there’s always a slim risk when plugging a laptop into an unknown power source. Faulty cables can also be a problem. Microsoft acknowledges this by saying that you can charge a Surface with a USB-C port, but it’s highly recommended that you use the Surface charger that came with the laptop because a USB-C charger would end up being very slow due to how power is metered within the device. In short, it’s a good idea to buy cables and chargers from reputable sources and think twice about using that cable you found laying on the ground in a conference room.
Because USB-C is universal and can do multiple things at once, this allows for some unique charging circumstances. Two worth noting are:
Pass-through: Today’s charging hubs also offer something called pass-through charging. This refers to a hub that can connect multiple USB peripherals to a laptop while also charging that laptop’s battery. Basically, it’s a combination between a hub and a USB-C charging cable, so you don’t need two different USB-C ports for each task. HooToo’s popular 6-in-1 USB-C Hub is a good example of this technology. There are other innovative options, too, like sending video to an external monitor while also making sure your laptop is charged in a presentation.
Portable chargers: Maybe you have a portable charger with an old USB connection but a phone that only has a USB-C connection (which is not compatible with older USB ports). You can link the charger to a laptop that has both types of ports, and use it to power up your phone in a roundabout way. Do not try to use your laptop Type C charger to charge your phone directly. The voltage requirements are too different for most devices currently available, and multi-device chargers are still a nascent part of the market.
There’s a variant of USB-C that’s a lot more powerful — Thunderbolt 3. Choose a laptop with at least one Thunderbolt 3-enabled USB-C port, and you can connect multiple 4K monitors at 60Hz and greatly increase your laptop’s gaming performance via an external GPU enclosure.
Thunderbolt 3 allows for a number of charging arrangements: It can “chain” up to six different devices together and easily charge while transmitting data at higher speeds than USB-C alone, up to 100W.
Since Thunderbolt 3 uses the same connection as USB-C, manufacturers are quick to label laptop ports if they also have Thunderbolt 3 technology — you can usually tell just by reading their descriptions. However, Thunderbolt 3 connections only work if you use the right cables, so make sure you have Thunderbolt 3 cables if you want to take advantage of those ports’ full features and bandwidth.
For Apple users
Apple users should know that they aren’t immune to the USB-C transition we’re seeing. Currently, Apple uses Lightning cables for iOS charging, a proprietary design that silos off of all Apple mobile charging accessories. The company has already switched to USB-C charging for MacBooks, and today’s iPad Pros also use USB-C charging. iPhones and iPads are currently unique in their Lightning cable reliance.
Apple is going to have to reimagine their current Lightning cable situation to fulfill the EU’s suspected precedent, demanding a set model of USB-C charging cables. Failure to comply with these demands will result in the loss of valuable European laptop buyers. Combine that with speculation of Apple ditching charging cables entirely, instead of focusing on a portless setup (most likely using a magnetic attachment on the back of the iPhone), and we may see the end of the Lightning cable in the next couple of years.
Current USB options are about to receive a major overhaul. According to industry insiders, not only will USB have the fastest speeds ever, but they will also be universally compatible across all brands of devices. The dawn of 2021 could see an entirely new generation of laptops that espouse the new USB4 port. Of course, USB4 adds yet another layer of complexity when it comes to USB protocols. There’s even more to know about the new tech:
We’re guessing that all other ports may start giving way to the USB-C. USB-C ports will soon outweigh all other ports in importance, taking over as the primary port. In the future, USB4 and Thunderbolt will likely be the standard.
Source: https://www.digitaltrends.com/computing/charging-via-usb-c/
Codecs are encoding and decoding algorithms that compress audio into manageable data packets for faster or wireless transmission. The efficiency of the codec will determine the quality and rate at which the audio data is sent. SBC is the default sub-band coding for most Bluetooth devices. However, since this codec has a relatively high latency and may be a bit lossy, companies have developed their own encoding algorithms, like Samsung’s UHQaudio and Sony’s LDAC.
The 3 main codecs that most listeners are familiar with are SBC, AAC, and aptX/HD:
SBC – Sub-band Coding – The mandatory and default codec for all stereo Bluetooth headphones with the Advanced Audio Distribution Profile (A2DP). It is capable of bit rates up to 328 kbps with a sampling rate of 44.1kHz. It provides fairly good audio quality without requiring a lot of processing power to encode or decode. However, the audio quality can be a bit inconsistent at times. This is especially noticeable with a cheap Bluetooth transmitter.
AAC – Advanced Audio Coding – Similar to SBC, but with better sound quality. This codec is mostly popular with Apple’s iTunes platform and some other non-wireless applications. However, it’s not very common, especially for headphones.
aptX – A proprietary and optional codec designed by CSR. It’s ideal for demanding audio applications since it encodes audio more efficiently and at a slightly higher rate than SBC. There are also two additional variations, aptX Low Latency and aptX HD, that either drastically reduces the latency of the connection or significantly improves its audio quality. However, it’s a bit limiting, as both the Bluetooth transmitter and receiver must have aptX or its variations for the codec to work.
Casablanca | Ennah | 2019
1. Create Big Sur Installation USB:
– From a Macbook that already have Big Sur installed, download Big Sur from Apple Store.
– Run this command to setup an install media (USB):
sudo /Applications/Install\ macOS\ Big\ Sur.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume
Change MyVolume with the name of USB drive
2. Install new MacOS from USB:
– Press and hold the Option (Alt) key immediately after turning on or restarting your Mac.
– Select the volume containing the bootable installer. Then click the up arrow to install.
– Maybe use Disk Utility to erase the old Hard drive of the Macbook first.
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Hình như chỉ còn duy nhất QĐ ND VN là dùng mũ cối? Hình như quân GP ND TQ bỏ mũ cối rồi? Mũ cối nguyên là của TQ chuyển sang ta, từ thời chiến, ta độ lại thành rởm hơn và dùng đến giờ như 1 truyền thống quý báu.
Continue readingHere’s a way to get your drafts folder back. Note that all previous saved mails are lost.
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