高壓雙管反激變換器的設(shè)計:介紹一種雙管反激的電路拓?fù)洌治隽似涔ぷ髟恚o出了一些關(guān)鍵技術(shù)參數(shù)的計算公式，設(shè)計并研制成功的30W 380V AC5 0H z/510V DC/+15.1 V DC(1A )、+5.2VDC(2A)輔助開關(guān)電源具有功率密度高、變換效率高、可靠性高等優(yōu)良的綜合性能。該變換器在高電壓輸人情況下有重要的應(yīng)用價值。【關(guān) 鍵 詞 】變換器，輔助開關(guān)電源，雙管反激
[Abstract】 A n e wt opologyfo rd oubles witchfl ybackc onverteris in troduced.Th eo perationp rincipleis a nalyzeda nds ome for mulas for calculating key parameters for the topology are presented. The designed and produced auxiliary switching power supply,i. e. 30W 380V AC5 0H z/5 10V DC/+15.1 V DC《1A )、+5.2 V DC《2A )，hase xcellentc omprehensivep erformances sucha sh ighp owerd ensity, hi ghc onversione fficiencya ndh ighr eliability.Th isc onverterh asim portanta pplicationv aluef orh igh input voltag
[Keywords ]converter,au xiliary switchingp owers upply,do ubles witchf lybac
ERWIN絕好的數(shù)據(jù)庫建模工具,可以把數(shù)據(jù)模型導(dǎo)入數(shù)據(jù)庫如sql server foxpro等這里是方法指南更多內(nèi)容可以去http://erwin.softwarechn.com/_script/showfull.asp?Board=method&Tabname=erwin
SQL Server 2005 Integration Services (SSIS) is a new Extract, Transform, and Load (ETL) tool that ships with SQL Server 2005. As with many of Microsoft s development tools, you can extend SSIS to perform other operations not already bundled with the product. SSIS provides the SSIS Class Library for just this purpose. The SSIS Class Library Object Model includes all the classes and interfaces you need to extend or augment SSIS.
- Convert file (plain text) or clipboard content among the following
encodings: big5, gbk, hz, shift-jis, jis, euc-jp, unicode big-endian,
unicode little-endian, and utf-8.
- Batch files conversion
- Preview file content and converted result before actual conversion.
文本計算器是一款為經(jīng)常需要使用計算器的工程項目人士而設(shè)計的軟件，該軟件使用簡單、方便。
當(dāng)需要計算數(shù)據(jù)時，在窗口中輸入整個表達(dá)式（表達(dá)式可以是加+、減-、乘*、除/、平方^、括號()，以及數(shù)學(xué)函數(shù)組合），按回車后可自動計算出結(jié)果，計算方法一目了然，便于查找計算中可能出現(xiàn)的錯誤。
支持的數(shù)學(xué)函數(shù)：cos(), sin(), tg(), ctg(), abs(), sgn() or sign(), sqrt(), ln(),sh() or sinh(), ch() or cosh(), th() or tanh(),cth() or coth(), heaviside()
