RFID (radio-frequency identification) is the use of a wireless non-contact system that uses radio-frequencyelectromagnetic fields to transfer datafrom a tag attached to an object, for the purposes of automatic identification and tracking [38]. The basic technologies for RFID have been around for a long time. Its root can be traced back to an espionage device designed in 1945 by Leon Theremin of the Soviet Union,whichretransmittedincidentradiowaves modulatedwith audioinformation. After decades of development, RFID systems have gain more and more attention from both the research community and the industry.
標簽： Infrastructure RFID as an
上傳時間： 2020-06-08
上傳用戶：shancjb
I wrote this book so that students, hobbyists, and engineers alike can take advantage of the Arduino platform by creating several projects that will teach them about the engineering process. I also wanted to guide the reader through introductory projects so that they could get a firm grasp on the Arduino Language, and how to incorporate several pieces of hardware to make their own projects. This book offers so much information on the Arduino, not just the basic LED projects but it offers different peripherals such as Ultrasonic sensor, the Xbox? controller, Bluetooth, and much more. This book also teaches the non-engineer to follow a process that will help them in future project (not just Arduino projects).
標簽： Engineering Practical Arduino
上傳時間： 2020-06-09
上傳用戶：shancjb
The main aim of this book is to present a unified, systematic description of basic and advanced problems, methods and algorithms of the modern con- trol theory considered as a foundation for the design of computer control and management systems. The scope of the book differs considerably from the topics of classical traditional control theory mainly oriented to the needs of automatic control of technical devices and technological proc- esses. Taking into account a variety of new applications, the book presents a compact and uniform description containing traditional analysis and op- timization problems for control systems as well as control problems with non-probabilistic models of uncertainty, problems of learning, intelligent, knowledge-based and operation systems – important for applications in the control of manufacturing processes, in the project management and in the control of computer systems.
上傳時間： 2020-06-10
上傳用戶：shancjb
The PW5300 is a current mode boost DC-DC converter. Its PWM circuitry with built-in 0.2? powerMOSFET make this regulator highly power efficient. The internal compensation network alsominimizes as much as 6 external component counts. The non-inverting input of error amplifierconnects to a 0.6V precision reference voltage and internal soft-start function can reduce the inrushcurrent. The PW5300 is available in the SOT23-6L package and provides space-saving PCB for theapplication fields
標簽： pw5300
上傳時間： 2022-02-11
上傳用戶：jiabin
解讀 5G 八大關鍵技術 【摘要】5G 不是一次革命，5G 是 4G 的延續，我相信 5G 在核心網部分不會有太 大的變動，5G 的關鍵技術集中在無線部分。 在進入主題之前，我覺得首先應該弄清楚一個問題：為什么需要 5G？不是因 為通信工程師們突然想改變世界，而炮制了一個 5G。是因為先有了需求，才有了 5G。什么需求？ 未來的網絡將會面對：1000 倍的數據容量增長，10 到 100 倍的無線設備連接， 10 到 100 倍的用戶速率需求，10 倍長的電池續航時間需求等等。坦白的講，4G 網絡無法滿足這些需求，所以 5G 就必須登場。 但是，5G 不是一次革命。5G 是 4G 的延續，我相信 5G 在核心網部分不會有 太大的變動，5G 的關鍵技術集中在無線部分。雖然 5G 最終將采用何種技術，目前 還沒有定論。不過，綜合各大高端論壇討論的焦點，我今天收集了 8 大關鍵技術。 當然，應該遠不止這些。 1.非正交多址接入技術 （Non-Orthogonal Multiple Access,NOMA） 我們知道 3G 采用直接序列碼分多址（Direct Sequence CDMA ，DS-CDMA） 技術，手機接收端使用 Rake 接收器，由于其非正交特性，就得使用快速功率控制 （Fast transmission power control ，TPC)來解決手機和小區之間的遠-近問題。 而 4G 網絡則采用正交頻分多址（
標簽： 5G
上傳時間： 2022-02-25
上傳用戶：20125101110
mosfet并聯使用介紹了并聯使用的注意事項，特別注意避開Vgsth zero thermal coefficient以下的正溫特性設計
上傳時間： 2022-03-01
上傳用戶：bluedrops
華為AI安全白皮書2018-cn近年來，隨著海量數據的積累、計算能力的發展、機器學習方法與系統的持續創新與演進，諸如圖像識別、語音識 別、自然語言翻譯等人工智能技術得到普遍部署和廣泛應用。越來越多公司都將增大在AI的投入，將其作為業務發展 的重心。華為全球產業愿景預測：到2025年，全球將實現1000億聯接，覆蓋77%的人口；85%的企業應用將部署到 云上；智能家庭機器人將進入12%的家庭，形成千億美元的市場。 人工智能技術的發展和廣泛的商業應用充分預示著一個萬物智能的社會正在快速到來。1956年，麥卡錫、明斯基、 香農等人提出“人工智能”概念。60年后的今天，伴隨著谷歌DeepMind開發的圍棋程序AlphaGo戰勝人類圍棋冠 軍，人工智能技術開始全面爆發。如今，芯片和傳感器的發展使“+智能”成為大勢所趨：交通+智能，最懂你的 路；醫療+智能，最懂你的痛；制造+智能，最懂你所需。加州大學伯克利分校的學者們認為人工智能在過去二十年 快速崛起主要歸結于如下三點原因[1]：1）海量數據：隨著互聯網的興起，數據以語音、視頻和文字等形式快速增 長；海量數據為機器學習算法提供了充足的營養，促使人工智能技術快速發展。2）高擴展計算機和軟件系統：近 年來深度學習成功主要歸功于新一波的CPU集群、GPU和TPU等專用硬件和相關的軟件平臺。3）已有資源的可獲得 性：大量的開源軟件協助處理數據和支持AI相關工作，節省了大量的開發時間和費用；同時許多云服務為開發者提供 了隨時可獲取的計算和存儲資源。 在機器人、虛擬助手、自動駕駛、智能交通、智能制造、智慧城市等各個行業，人工智能正朝著歷史性時刻邁進。谷 歌、微軟、亞馬遜等大公司紛紛將AI作為引領未來的核心發展戰略。2017年谷歌DeepMind升級版的AlphaGo Zero橫 空出世；它不再需要人類棋譜數據，而是進行自我博弈，經過短短3天的自我訓練就強勢打敗了AlphaGo。AlphaGo Zero能夠發現新知識并發展出打破常規的新策略，讓我們看到了利用人工智能技術改變人類命運的巨大潛能。 我們現在看到的只是一個開始；未來，將會是一個全聯接、超智能的世界。人工智能將為人們帶來極致的體驗，將 積極影響人們的工作和生活，帶來經濟的繁榮與發展。
上傳時間： 2022-03-06
上傳用戶：
隨著光伏發電系統快速發展,以及電動汽車充電樁的普及,傳統的剩余電流保護器無法滿足實際需求。介紹了一款B型剩余電流保護器,采用磁調制剩余電流互感器和零序電流互感器采集剩余電流。根據GB/T 22794—2017標準要求,可識別1 kHz及以下的正弦交流、帶和不帶直流分量的脈動直流、平滑直流等剩余電流信號。經信號調理電路將電壓信號送到單片機進行采集和判斷。通過試驗測試,該樣機在測試精度和速度上均符合國家標準的相關要求。The rapid development of photovoltaic power generation systems and the popularity of electric vehicle charging piles make the traditional residual current protective devices unable to meet the actual demand.This paper proposed a type B residual current protective device,which uses the magnetically modulated residual current transformer and the zero sequence current transformer to acquire the residual current.According to the requirements of GB/T 22794—2017,the type B residual current protective device can detect sinusoidal AC residual current of 1kHz and below 1kHz,pulsating DC residual current with and without DC component,smooth DC residual current and so on.The signal processing circuit sends the voltage signal to the MCU for acquisition and judgment.Through experimental tests,the device meets the relevant requirements of national standards in terms of test accuracy and speed.
標簽： 電流保護器
上傳時間： 2022-03-27
上傳用戶：
溫度控制如今已成為當代社會研究的熱點之一,而溫度檢測在現代設備參數檢測中也是一項極其重要的技術,應用十分廣泛。與傳統的測溫方法相比,紅外測溫方法具有時間短、精度高、使用簡單方便等優點。本文以環境溫度為被測對象,設計了以STC89C52單片機為控制中心的紅外測溫裝置,能夠實現對目標溫度的實時采集、處理、顯示和報警等功能。本設計主要是由STC89C52單片機、紅外測溫傳感器、LCD1602液晶顯示器、按鍵和蜂鳴器等部分組成,采用非接觸的方式對目標溫度進行實時檢測。Temperature control has become one of the hotspots in contemporary social research,and temperature detection is an extremely important technology in modern equipment parameter detection.Compared with traditional method,the infrared temperature measuring method has advantages of short time,high precision and convenient operation,etc.This paper consider environment temperature as research objects and designs an infrared temperature measuring device which employs the STC89C52singlechipas-control center,and it can realize timely collection,processing,display and alarm function of the target temperature.The design is mainly composed of STC89C52 singlechip,infrared temperature sensor,LCD1602monitor,keys and buzzer,etc.This design detects the target temperature by non-contact method.
上傳時間： 2022-03-27
上傳用戶：jiabin
本系統基于STM32單片機設計的非接觸式電流檢測控制系統,通過OPA548片將所給任意信號放大,由100Ω電阻和INA128芯片進行電流電壓轉換放大后,利用STM32單片機對獲取的電壓信號以0.488μs頻率采樣,利用STM32單片機的FFT庫,獲得信號的諧波信息。測量電流信號精準,該設計可廣泛應用在以STM32單片機為核心控制器件的新型儀表中,性能精準且抗干擾能力強。This system is a non-contact current detection and control system based on STM32 single chip microcomputer. It amplifiesany signal through OPA548 chip, converts and amplifies the current and voltage by 100 Ω resistance and INA128 chip. The obtainedvoltage signal is sampled at the frequency of 0.488 μs by STM 32 single chip microcomputer, and the harmonic information of the signalis obtained by the FFT library of STM 32 single chip microcomputer. The measurement of current signal is accurate. This design can bewidely used in a new instrument with STM 32 single chip microcomputer as its core control device, with accurate performance and stronganti-interference capability.
上傳時間： 2022-03-27
上傳用戶：
