Many good textbooks exist on probability and random processes written at the under- graduate level to the research level. However, there is no one handy and ready book that explains most of the essential topics, such as random variables and most of their frequently used discrete and continuous probability distribution functions; moments, transformation, and convergences of random variables; characteristic and generating functions; estimation theory and the associated orthogonality principle; vector random variables; random processes and their autocovariance and cross-covariance functions; sta- tionarity concepts; and random processes through linear systems and the associated Wiener and Kalman filters.
標簽： Probability Processes Random and
上傳時間： 2020-05-31
上傳用戶：shancjb
When 3GPP started standardizing the IMS a few years ago, most analysts expected the number of IMS deploymentsto grow dramatically as soon the initial IMS specifications were ready (3GPP Release 5 was functionallyfrozenin the first half of 2002and completedshortly after that). While those predictions have proven to be too aggressive owing to a number of upheavals hitting the ICT (Information and Communications Technologies) sector, we are now seeing more and more commercial IMS-based service offerings in the market. At the time of writing (May 2008), there are over 30 commercial IMS networks running live traffic, addingup to over10million IMS users aroundthe world; the IMS is beingdeployedglobally. In addition, there are plenty of ongoing market activities; it is estimated that over 130 IMS contracts have been awarded to all IMS manufacturers. The number of IMS users will grow substantially as these awarded contracts are launched commercially. At the same time, the number of IMS users in presently deployed networks is steadily increasing as new services are introduced and operators running these networks migrate their non-IMS users to their IMS networks.
標簽： Multimedia Subsystem The IMS 3G IP
上傳時間： 2020-06-01
上傳用戶：shancjb
I am presenting this novel book on advances and trends in power electronics and motor drives to the professional community with the expectation that it will be given the same wide and enthusiastic acceptance by practicing engineers, R&D professionals, univer- sity professors, and even graduate students that my other books in this area have. Unlike the traditional books available in the area of power electronics, this book has a unique presentation format that makes it convenient for group presentations that use Microsoft’s PowerPoint software. In fact, a disk is included that has a PowerPoint file on it that is ready for presentation with the core figures. Presentations can also be organized using just selected portions of the book
標簽： Electronics Advances Drives Power Motor And
上傳時間： 2020-06-10
上傳用戶：shancjb
題目：基于51單片機的RS485從機系統設計 單片機接口資源配置： 1. 上電復位電路； 2. 晶振電路采用11.0592Mhz晶振； 3. 485接口電路（P3.7用于485芯片的收發控制，收發管腳接單片機的rxd和txd）； 4. P2口通過外部跳線接相應的高低電平，配置從機地址為組號； 5. P3.6外接一發光二極管（注意串聯電阻進行限流）； 6. P3.2外接一按鍵，斷開高電平，按下低電平； 7. 按鍵檢測采用外部中斷方式，下跳沿觸發； 8. 單片機定時器0以模式1（16位模式）工作，產生50ms的定時中斷，并在此基礎上設計一單片機內部時鐘（24小時制，能計數時、分、秒、50ms值）； 9. 單片機串行通信采用模式1非多機通信方式，采用9600波特率以串行中斷方式進行數據的收發通信，主機地址為0xF0，廣播地址為0xFF。 系統功能需求： 1. 系統配置和自檢功能： l 從機上電后進行初始化，通過讀取P2口進行從機地址配置； l 發光二極管以每秒一次的頻率閃爍（亮0.5秒，滅0.5秒）； l 檢測到一次按鍵按下操作后，熄滅發光二極管。 2. 數據接收和按鍵計時功能： l 從機接收主機程序（PC機上的串口調試程序）的按鍵允許命令幀并進行校驗； l 校驗正確并且目的地址是廣播地址或者本從機的地址，通過發光二極管長亮指示，并允許按鍵操作； l 按鍵按下后，盡可能準確記錄按鍵的動作時點（定時器的低8位、定時器的高8位、50ms值、秒、分、小時）； l 按鍵操作只能響應一次，重復按鍵操作不響應； l 按鍵的動作時點記錄后，發光二極管以每秒一次的頻率閃爍（亮0.5秒，滅0.5秒）。 3. 數據發送功能： l 從機接收主機程序發來的時鐘數據搜索命令幀并進行校驗； l 如果校驗正確并且數據幀的目的地址是本從機的地址，從機將前面記錄的按鍵動作時點數據（定時器的低8位、定時器的高8位、50ms值、秒、分、小時）按附錄中的時鐘數據返回幀的幀格式回傳給主機； l 時鐘數據返回幀回傳結束后，熄滅發光二極管。 4. 校驗和生成和檢測功能： l 發送數據幀時能自動生成數據幀校驗和； l 每幀數據在發送幀尾前，發送一字節的當前幀數據的校驗和； l 接收數據幀時能檢測校驗和并判斷接收數據是否正確。 附錄：幀定義 校驗和的計算：除去幀頭和幀尾后將幀中的其他數據求和并取低8位； 幀長：不計幀頭、幀尾和校驗和字節。 按鍵允許命令幀： 幀頭 幀長 目的地址 源地址 命令字 校驗和 幀尾 AA 04 FF F0 01 F4 66 時鐘數據搜索命令幀： 幀頭 幀長 目的地址 源地址 命令字 保留字 校驗和 幀尾 AA 05 01 F0 03 00 F9 66 時鐘數據返回幀： 幀頭 幀長 目的地址 源地址 命令字 TL0 TH0 50ms 秒 分 時 校驗和 幀尾 AA 0A F0 01 07 01 B6 09 03 00 00 C5 66 幀結構頭文件frame.h（內容如下） //幀格式定義 #define FRAME_HEAD 0xAA //幀頭 #define FRAME_FOOT 0x66 //幀尾 #define FRAME_LEN 0x00 //幀長 #define FRAME_DST_ADR 0x01 //目的地址 #define FRAME_SRC_ADR 0x02 //源地址 #define FRAME_CMD 0x03 //命令字 #define FRAME_DATA 0x04 //幀數據起始 //幀命令定義 #define READY 0x01 //按鍵允許命令 #define TIME_SERCH 0x03 //時鐘數據輪詢命令 #define TIME_BACK 0x07 //時鐘數據返回命令 //地址定義 #define BROAD_ADR 0xFF //廣播地址 #define MASTER_ADR 0xF0 //主機地址
上傳時間： 2020-06-18
上傳用戶：umuo
用的是沁恒CH552e淘寶買的評估板，USB中斷上傳程序用的是沁恒提供的做了些修改。程序使用2個端點一個，端點1作為普通鍵盤，端點2作為多媒體按鍵，有詳細注釋多媒體按鍵報告，以下是主函數內容。/****主函數****/main(){ CfgFsys( ); //CH552時鐘選擇配置 mDelaymS(5); //修改主頻等待內部晶振穩定,必加 ConfigT0(2); //配置2ms T0中斷 USBDeviceInit(); //USB設備模式初始化 EA = 1; //允許單片機中斷 UEP1_T_LEN = 0; //預使用發送長度一定要清空 UEP2_T_LEN = 0; //清空端點2發送長度 FLAG = 0; //清空USB中斷傳輸完成標志 Ready = 0; LED_VALID = 1; //給一個默認值 P1_DIR_PU &= 0xE0; //在MOD_OC為0時 p1.5 p1.6 P1.7為推挽輸出 P1_MOD_OC = P1_MOD_OC & ~0xE0; //3個口的bit4 = 0 p1.5 p1.6 P1.7設置為推挽輸出 P1_DIR_PU = P1_DIR_PU | 0xE0; //3個口的bit4 = 1 p1.5 p1.6 P1.7設置為輸出 key1 = 1; key2 = 1; key3 = 1; while(1) { KeyDrive(); //按鍵驅動 }}
上傳時間： 2022-05-15
上傳用戶：
Mathematical modeling has become an important part of the research and devclopment work in engineering and scicnce. Retaining a competitive edge requiresa fast path between ideas and prototypes, and in this regard mathematical modeling and simulation provide a valuable shortcut for understanding both qualitative and quantitative aspects of scientific and engineering design. To assist you in gaining this edge, COMSOL Multiphysics offers state-of-the art performance, being built from the ground up with a Java3D interface and C/C++ solvers.The Acoustics Module is an optional package that extends the COMSOL Multiphysicsmodcling cnvironment with customized user interfaces and functionality optimizcd for the analysis of acoustics. Like all modules in the COMSOL family, it provides a brary of prewritten ready-to-run models that make it quicker and casier to analyze disciplinc-specific problcms.
上傳時間： 2022-06-19
上傳用戶：
藍牙低能耗（Bluetooth Low Energy，或稱Bluetooth LE、BLE，舊商標Bluetooth Smart）也稱低功耗藍牙，是藍牙技術聯盟設計和銷售的一種個人局域網技術，旨在用于醫療保健、運動健身、信標、安防、家庭娛樂等領域的新興應用。相較經典藍牙，低功耗藍牙旨在保持同等通信范圍的同時顯著降低功耗和成本011年，藍牙技術聯盟（SIG）發表了“藍牙智能”徽標，體現低功耗設備與藍牙設備的兼容性。具有“藍牙智能就緒”（Bluetooth Smart Ready）標識的外設兼容經典藍牙與低功耗藍牙的雙模。具有“藍牙智能”（Bluetooth Smart）標識的設備僅支持低功耗藍牙，可以與“藍牙智能就緒”或“藍牙智能”設備通信。根據2016年5月藍牙技術聯盟的品牌信息，藍牙技術聯盟開始逐步停用“藍牙智能”和“藍牙智能就緒”標識，恢復使用“Bluetooth”圖案標志和文字標識。標志使用新款藍色
標簽： 低功耗藍牙
上傳時間： 2022-07-26
上傳用戶：
