Dvorak keyboard
Dvorak is a keyboard arrangement of the letters, Dvorak keyboard is designed to be more than the standard-QWERTY keyboard, ergonomic, basically it easier to learn and use.
1920, August Dvorak and William Dealey co-developed called "Dvorak" keyboard arrangement of a simplified method, after over 12 years to constantly adjust and hope to perfect. Dvorak keyboard in the design process, consider the typist of the human condition, the keyboard is designed to take the structure arranged in alphabetical way easier than on the QWERTY design and win their letters correctly, while the average number of letters hand percussion, shorter distance to move. In addition, Dvorak keyboard is also suitable for single-handed typing input methods.
As for the QWERTY, is the mass of the keyboard letters are more frequently used arrangement, the first line of the letters from left to right precisely from QWERTY, which was named after. QWERTY arrangement of letters used mainly to enable the keyboard is closer to the central authorities.
Microsoft Windows and Macintosh operating systems support the Dvorak keyboard, manufactured recently by some companies can support the QWERTY and Dvorak keyboard, which allows users to switch in accordance with customary. While the QWERTY keyboard as the market mainstream, but there is still a small majority of users prefer to use a more ergonomic Dvorak keyboard.
DVR digital video playback system
Digital video playback system, the rise of VCR market from making a revolution. DVR with recorded images kept in digital form, with integrated high, versatile, repeatable video, image search for convenient, quality clear, gradually replaced the VCR as the mainstream market, but also a digital image monitoring system of core products. DVR using digital compression technology, with the hard drive to store images, set image segmentation, video switching, video functions in one machine can connect sensors, alarms, still have a motion detection, transmission of images through the Internet and control signals and other functions.
In the field of digital home appliances, DVR stressed that the digital, using hard disk drives and the use of MPEG II compression / decompression chip that can record more than 30 hours of programming, but also to access the content of these programs, no rewind, can be like a computer Crawl information readily accessible. Advantage lies not only with the DVR recorded with the broadcasting of digital TV in the next launch after another, the traditional VCR will gradually be eliminated, DVR will become one of the mainstream of digital appliances.
DWDM dense wavelength division multiplexer
The growing popularity of the Internet and transfer the file size growing synergistic effects, the optical fiber communication begun to enter the "time multi-tasking" and "wavelength multiplexing," combining "DWDM" era.
The response of the national carriers that have expanded network bandwidth Road, from the long-haul wide area network (WAN) to local area network (LAN), started laying fiber-optic network, which makes the optical fiber communication system equipment market to soar but also promote the growth of components.
DWDM transmission via Ethernet, is the core network will be based some of the most common choice, because compared to other building modules, it has scalability advantages. However, with the introduction of other new technologies such as MPLS, and S-MLT, through the optical transmission of the Ethernet-based networks will become a core part of an attractive option to increase its scalability and re-election Path time.
Dynamic Execution Processor
Intel (INTEL) P6 MICROARCHITECTURE micro-architecture of the core (CORE) function, use the techniques include: 1. MULTIPLE BRANCH PREDICTION: multi-branch prediction is used to speed up the decoding and execution process .2. DATAFLOW ANALYSIS: Analysis and instruction (INSTRUCTION) related to information to reorder instruction execution plan .3. SPECULATIVE EXECUTION: guess instruction execution to keep superscalar (SUPERSCALAR) framework for continuous operation. |
