郵件系統(tǒng)是Linux網(wǎng)絡(luò)應(yīng)用的重要組成，一個完整的郵件系統(tǒng)包括三個部分：底層操作系統(tǒng)（Linux Operation），郵件傳送代理（Mail Transport Agent，MTA），郵件分發(fā)代理（Mail Delivery Agent，MDA），郵件用戶代理（Mail User Agent，MUA）。 Postfix是一個非常優(yōu)秀的MTA，她素以高效、安全的特點而著稱。Postfix是作者在UNIX上所見過的MTA中在反垃圾郵件（Anti- Spam或Anti-UCE）方面做得最好的一個，甚至有很多公司在Postfix代碼的基礎(chǔ)上進行二次開發(fā)而推出反垃圾郵件網(wǎng)關(guān)產(chǎn)品。MTA的反垃圾郵件功能，實際上就是在MTA處理過程中對會話進行過濾。這個過濾不但過濾了發(fā)往自身的垃圾郵件，而且還防止了自身被惡意利用發(fā)送垃圾郵件。Postfix 實現(xiàn)了目前所有主要的MTA過濾技術(shù)。postfix是Wietse Venema在IBM的GPL協(xié)議之下開發(fā)的MTA（郵件傳輸代理）軟件。和Sendmail相比Postfix更快、更容易管理、更靈活、更安全。
標(biāo)簽： Linux 郵件系統(tǒng) 網(wǎng)絡(luò)應(yīng)用
上傳時間： 2015-11-25
上傳用戶：dapangxie
The MAX504/MAX515 are low-power, voltage-output, 10-bit digital-to-analog converters (DACs) specified for single +5V power-supply operation.用于DA轉(zhuǎn)換芯片選型
標(biāo)簽： digital-to-analog voltage-output converters MAX
上傳時間： 2015-11-26
上傳用戶：541657925
Jitter is extremely important in systems using PLL-based clock drivers. The effects of jitter range from not having any effect on system operation to rendering the system completely non-functional. This application note provides the reader with a clear understanding of jitter in high-speed systems. It introduces the reader to various kinds of jitter in high-speed systems, their causes and their effects, and methods of reducing jitter. This application note will concentrate on jitter in PLL-based frequency synthesizers.
標(biāo)簽： extremely PLL-based important drivers
上傳時間： 2014-11-25
上傳用戶：asddsd
This demonstration shows that reordering the rows and columns of a sparse matrix S can affect the time and storage required for a matrix operation such as factoring S into its Cholesky decomposition
標(biāo)簽： demonstration reordering the columns
上傳時間： 2016-01-14
上傳用戶：奇奇奔奔
ST7529液晶驅(qū)動 The ST7529 is a driver & controller LSI for 32 gray scale graphic dot-matrix liquid crystal display systems. It generates 255 Segment and 160 Common driver circuits. This chip is connected directly to a microprocessor, accepts Serial Peripheral Interface (SPI), 8-bit/16-bit parallel or IIC display data and stores in an on-chip display data RAM. It performs display data RAM read/write operation with no external operating clock to minimize power consumption. In addition, because it contains power supply circuits necessary to drive liquid crystal, it is possible to make a display system with the fewest components.
標(biāo)簽： 7529 controller dot-matrix graphic
上傳時間： 2013-12-02
上傳用戶：奇奇奔奔
編譯的關(guān)于LL(1)詞法分析的小程序，適合在VC下運行-compiled on LL (1) Morphological analysis of the small programs, for the VC teachers to run the operation no problem
上傳時間： 2014-09-01
上傳用戶：sjyy1001
matlab經(jīng)典算法的程序-特殊繪圖，figure operation
上傳時間： 2014-01-11
上傳用戶：yulg
Core JSP In recent years, a large amount of software development activity has migrated from the client to the server. The client-centric model, in which a client executes complex programs to visualize and manipulate data, is no longer considered appropriate for the majority of enterprise applications. The principal reason is deployment—it is a significant hassle to deploy client programs onto a large number of desktops, and to redeploy them whenever the application changes. Instead, applications are redesigned to use a web browser as a "terminal". The application itself resides on the server, formatting data for the user as web pages and processing the responses that the user fills into web forms.
標(biāo)簽： development activity migrated software
上傳時間： 2014-01-13
上傳用戶：duoshen1989
Summary Many control applications require converting some analog input to a digital format. The ADCINC12 User Module is a general-purpose, 12-bit analog to digital converter (ADC) that does just that. This Application Note is meant to be a simple introduction into its operation. The steps required to define, place, and write software are presented. Examples are developed in both assembly and C.
標(biāo)簽： applications converting Summary control
上傳時間： 2013-12-01
上傳用戶：WMC_geophy
The first task at hand is to set up the endpoints appropriately for this example. The following code switches the CPU clock speed to 48 MHz (since at power-on default it is 12 MHz), and sets up EP2 as a Bulk OUT endpoint, 4x buffered of size 512, and EP6 as a Bulk IN endpoint, also 4x buffered of size 512. This set-up utilizes the maximum allotted 4-KB FIFO space. It also sets up the FIFOs for manual mode, word-wide operation, and goes through a FIFO reset and arming sequence to ensure that they are ready for data operations
標(biāo)簽： appropriately The endpoints following
上傳時間： 2013-12-02
上傳用戶：dianxin61
蟲蟲下載站版權(quán)所有 京ICP備2021023401號-1
