The ability to write efficient, high-speed arithmetic routines ultimately depends upon your knowledge of the elements of arithmetic as they exist on a computer. That conclusion and this book are the result of a long and frustrating search for information on writing arithmetic routines for real-time embedded systems. With instruction cycle times coming down and clock rates going up, it would seem that speed is not a problem in writing fast routines. In addition, math coprocessors are becoming more popular and less expensive than ever before and are readily available. These factors make arithmetic easier and faster to use and implement. However, for many of you the systems that you are working on do not include the latest chips or the faster processors. Some of the most widely used microcontrollers used today are not Digital Signal Processors (DSP), but simple eight-bit controllers such as the Intel 8051 or 8048 microprocessors.
標簽： arithmetic high-speed ultimately efficient
上傳時間： 2014-11-30
上傳用戶：lizhen9880
Performance Comparison of Two On-Demand Routing Protocols depends on Traffic Density by Using UWB-IR as Pyhisical and MAC Layer at Outdoor Peer to Peer Sensor Network
標簽： Performance Comparison On-Demand Protocols
上傳時間： 2017-05-28
上傳用戶：三人用菜
A light-emitting diode (LED) is a semiconductor device that emits narrow-spectrum incoherent light when forward-biased.The color of the emitted light depends on the chemical composition of the semiconductor material used, and can benear-ultraviolet, visible or infrared. LEDs are more prevalent today than ever before, replacing traditional incandescent andfluorescent bulbs in many lighting applications. Incandescents use a heated filament, are subject to breakage and burnoutand operate at a luminous efficiency of 2% to 4%. Fluorescents are more efficient, at 7% to 12%, but require highdrive voltage and contain mercury, a toxic substance that may be eventually banned in certain countries. LEDs, however,produce light directly through electroluminescence, operate at low voltage and can deliver over 20% luminous efficiency.
上傳時間： 2013-11-07
上傳用戶：xiaoyuer
For a variety of reasons, it is desirable to charge batteriesas rapidly as possible. At the same time, overchargingmust be limited to prolong battery life. Such limitation ofovercharging depends on factors such as the choice ofcharge termination technique and the use of multi-rate/multi-stage charging schemes. The majority of batterycharger ICs available today lock the user into one fixedcharging regimen, with at best a limited number ofcustomization options to suit a variety of application needsor battery types. The LTC®1325 addresses these shortcomingsby providing the user with all the functionalblocks needed to implement a simple but highly flexiblebattery charger (see Figure 1) which not only addressesthe issue of charging batteries but also those of batteryconditioning and capacity monitoring.
上傳時間： 2013-10-19
上傳用戶：royzhangsz
The data plane of the reference design consists of a configurable multi-channel XBERT modulethat generates and checks high-speed serial data transmitted and received by the MGTs. Eachchannel in the XBERT module consists of two MGTs (MGTA and MGTB), which physicallyoccupy one MGT tile in the Virtex-4 FPGA. Each MGT has its own pattern checker, but bothMGTs in a channel share the same pattern generator. Each channel can load a differentpattern. The MGT serial rate depends on the reference clock frequency and the internal PMAdivider settings. The reference design can be scaled anywhere from one channel (two MGTs)to twelve channels (twenty-four MGTs).
上傳時間： 2013-12-25
上傳用戶：jkhjkh1982
The ICA/BSS algorithms are pure mathematical formulas, powerful, but rather mechanical procedures: There is not very much left for the user to do after the machinery has been optimally implemented. The successful and efficient use of the ICALAB strongly depends on a priori knowledge, common sense and appropriate use of the preprocessing and postprocessing tools. In other words, it is preprocessing of data and postprocessing of models where expertise is truly ne
標簽： mathematical algorithms mechanical procedures
上傳時間： 2015-03-31
上傳用戶：silenthink
動態鏈接庫程序的編寫。靜態庫與動態庫的區別，以及調用程序在鏈接靜態庫和動態庫時的區別。如何利用工具查看動態鏈接庫輸出的函數，depends工具的使用，C++編譯器名字改編技術對動態鏈接庫輸出函數的影響，extern "C"的用法，利用模塊定義文件來解決C++名字改編的問題。用typedef定義指向函數的指針類型，如何獲得動態連接庫里的函數的指針。
上傳時間： 2014-01-19
上傳用戶：llandlu
動態鏈接庫程序的編寫,如何利用工具查看動態鏈接庫輸出的函數，depends工具的使用
上傳時間： 2015-07-09
上傳用戶：清風冷雨
動態鏈接庫程序的編寫。靜態庫與動態庫的區別，以及調用程序在鏈接靜態庫和動態庫時的區別。如何利用工具查看動態鏈接庫輸出的函數，depends工具的使用，C++編譯器名字改編技術對動態鏈接庫輸出函數的影響，extern "C"的用法，利用模塊定義文件來解決C++名字改編的問題。用typedef定義指向函數的指針類型，如何獲得動態連接庫里的函數的指針。
上傳時間： 2016-04-30
上傳用戶：wuyuying
This standard describes a keyed-hash message authentication code (HMAC), a mechanism for message authentication using cryptographic hash functions. HMAC can be used with any iterative Approved cryptographic hash function, in combination with a shared secret key. The cryptographic strength of HMAC depends on the properties of the underlying hash function. The HMAC specification in this standard is a generalization of Internet RFC 2104, HMAC, Keyed-Hashing for Message Authentication, and ANSI X9.71, Keyed Hash Message Authentication Code.
標簽： message authentication keyed-hash describes
上傳時間： 2014-01-07
上傳用戶：鳳臨西北
