AN22 details the theoretical and application aspects of the LT1088 thermal RMS/DC converter. The basic Theory behind thermal RMS/DC conversion is discussed and design details of the LT1088 are presented. Circuitry for RMS/DC converters, wideband input buffers and heater protection is shown.
上傳時間： 2013-10-16
上傳用戶：china97wan
鎖定放大是微弱信號檢測的重要手段。基于相關檢測理論，利用開關電容的開關實現鎖定放大器中乘法器的功能，提出開關電容和積分器相結合以實現相關檢測的方法，并設計出一種鎖定放大器。該鎖定放大器將微弱信號轉化為與之相關的方波，通過后續電路得到正比于被測信號的直流電平，為后續采集處理提供方便。測量數據表明鎖定放大器前級可將10-6 A的電流轉換為10-1 V的電壓，后級通過帶通濾波器級聯可將信號放大1×105倍。該方法在降低噪聲的同時，可對微弱信號進行放大，線性度較高、穩定性較好。 Abstract: Lock-in Amplifying（LIA）is one of important means for weak signal detection. Based on cross-correlation detection Theory， switch in the swithched capacitor was used as multiplier of LIA， and a new method of correlation detection was proposed combining swithched capacitor with integrator. A kind of LIA was designed which can convert the weak signal to square-wave， then DC proportional to measured signal was obtained through follow-up conditioning circuit， providing convenience for signal acquisition and processing. The measured data shows that the electric current（10-6 A） can be changed into voltage（10-1 V） by LIA， and the signal is magnified 1×105 times by cascade band-pass filter. The noise is suppressed and the weak signal is amplified. It has the advantages of good linearity and stability.
上傳時間： 2013-11-29
上傳用戶：黑漆漆
在理論分析循環碼編碼和譯碼基本原理的基礎上，提出了基于單片機系統的(24，16)循環碼軟件實現編碼、譯碼的方案。仿真結果表明(24，16)循環碼能有效地克服來自通訊信道的干擾，保證數據通信的可靠及系統的穩定，使誤碼率大幅度降低。本論文對(24，16)循環碼的研究結果表明，可以有效地降低錯誤概率和提高系統的吞吐量，實現糾錯僅需要在接收端增加有限的存儲空間和計算復雜度，具有一定的實用價值。 Abstract: Based on analyzing the Theory of encoding and decoding of cyclic code， this paper showed the schemes of encoding and decoding of(24，16)cyclic code by the software and based on microcontroller. Simulation results show that using (24，16) cyclic codes can effectively overcome the interference from communication channel， ensure the reliability and stability of data communication systems， and reduce the bit error rate greatly. The results of this paper show that by using the (24，16) cyclic code， the error rate can be reduced and the system throughput can be improved. Meanwhile， the system only needs to enlarge limited storage space and computation the complexity at the receiving end to realize error correction. Thus the (24，16) cyclic code has a practical value.
上傳時間： 2013-11-09
上傳用戶：gaoliangncepu
為了提高傳統溫度控制系統的性能，將PID控制理論與嵌入式系統相結合，采用瑞薩電子公司的H8S/2166作為核心處理器，AD公司的AD7705以及熱敏電阻溫度傳感器作為溫度檢測單元，利用4×6小鍵盤、LCD顯示器和S1D13305液晶控制器達到良好的人機交互，設計出了一個應用于化工領域的嵌入式實時溫度控制系統。相比于傳統溫度控制系統，該系統提供了更強的計算能力和可擴展能力，采用增量PID控制算法實現復雜控制。通過實驗，該系統能達到0.1 ℃的溫度控制精度以及小于120 s的溫度穩定時間。 Abstract: In order to improve the performance of conventional temperature control system， combining PID control Theory with embedded systems， using the Renesas Electronics Corp. H8S/2166 micro-controller as a core processors， AD7705 and thermistor temperature sensor as a temperature detection unit and 4×6 small keyboard， LCD and S1D13305 LCD controller as a good human-computer interaction， this paper designed an embedded real-time temperature control system which is applied in chemical industry. Compared with conventional temperature control system， this system provides more computing power and extensibility， and adopts PID control algorithm for complex control. Through the experiment， the system can reach temperature control accuracy of 0.1 ℃ and temperature stabilization time of less than 120 seconds.
上傳時間： 2014-12-26
上傳用戶：003030
生活中許多目標的高度和水平距離需要進行測量。目前主要的測量方法，仍以傳統的皮尺丈量為主，測量效率不高，有時還很不方便，沒有技術成熟的數字式測高測距產品。以基本的數學方法為理論依據，利用遙控小車做為載體，采用角度傳感器測量角度、霍爾傳感器測量水平距離等，通過單片機LM3S615進行數據計算，實現了對待測目標物體的高度、水平距離等數據的快速、精確和數字式的測量，高度測量精度可達99.06%，水平測量精度則可達98.06%。 Abstract: In our lives， the height and horizontal distance of some goals are needed to be measured. Because the currently used methods are still traditional tape-based measuring methods， and the measuring efficiency is low and inconvenient so some kinds of digital and portable measuring methods or instruments are needed. Based on the basic math Theory， this paper designed and manufactured a portable， digital and remote controlled measuring mobile small vehicle， which assembled with angle measuring sensor for angle measurement and Hall sensor for horizontal distance measuring. MCU LM3S615 calculated the height and horizontal distance data gotten from these sensors. The measuring process is simple， the measuring results are more accurate and the measuring efficiency is higher than traditional measure instruments. The accuracy of height and distance measurement can reach 99.06% and 98.06%.
上傳時間： 2013-10-30
上傳用戶：jackandlee
針對材料試驗機等設備中要求測量或控制材料拉伸或壓縮的位移，一般采用光電軸角編碼器檢測位置信號，輸出正交編碼脈沖信號。若采用其他方法檢測位置信號，必然導致電路設計復雜，可靠性降低。因此，提出一種基于LS7266R1的電子式萬能材料試驗機設計方案。給出了試驗機中的控制器工作原理，LS7266R1與單片機的接口硬件設計，以及主程序軟件流程圖。巧妙地把力量傳感器，位移傳感器等機械運動狀態的壓力或拉力以及位置坐標，變成了電壓信號和電脈沖數字信號，供A/D測量和LS7266R1計數，從而實現了獨立完成材料試驗控制或通過PC機串口命令完成材料試驗控制。 Abstract: Aiming at the requirement that the displacement of the tension and compression always be tested and controlled in the equipement such as material testing machine. The position signal was tested by photoelectric axial angle coder. Therefore， the paper proposes the design of electronic universal testing machine design based on LS7266R1. If the position signal detected by other methods， will inevitably lead to the circuit design complexity， reliability decreased. The work Theory of the controller， the hardware interface design between LS7266R1 and single chip， and the flow chart of main program， are presented in this paper. The signal of the compression or tension power and displacement at working， which tested by power sensor and displacement sensor especially， is changed into electric voltage and electric pulse numerical signals. And these signals can be tested by A/D and counted by LS7266R1. Finally the test of the material properties can be controlled by itself， or controlled by the COM command of PC.
上傳時間： 2013-11-02
上傳用戶：yl1140vista
最新的支持向量機工具箱，有了它會很方便 1. Find time to write a proper list of things to do! 2. Documentation. 3. Support Vector Regression. 4. Automated model selection. REFERENCES ========== [1] V.N. Vapnik, "The Nature of Statistical Learning Theory", Springer-Verlag, New York, ISBN 0-387-94559-8, 1995. [2] J. C. Platt, "Fast training of support vector machines using sequential minimal optimization", in Advances in Kernel Methods - Support Vector Learning, (Eds) B. Scholkopf, C. Burges, and A. J. Smola, MIT Press, Cambridge, Massachusetts, chapter 12, pp 185-208, 1999. [3] T. Joachims, "Estimating the Generalization Performance of a SVM Efficiently", LS-8 Report 25, Universitat Dortmund, Fachbereich Informatik, 1999.
上傳時間： 2013-12-16
上傳用戶：亞亞娟娟123
這里是我在學校時所寫的一些程序，其中有些Java程序可能要重新編譯一下才能運行，具體如下：C Course Disign——C語言編寫的時鐘程序Very Simple CPU——CPU仿真工具StudentQuery——基于SQL語言數據庫的學籍管理系統Theory of Computation——一些關于計算理論算法的實現，詳見內附說明Hotel——酒店管理系統另外還有一些硬件VHDL方面的程序，整理好后會陸續上傳
上傳時間： 2013-12-26
上傳用戶：onewq
This a Bayesian ICA algorithm for the linear instantaneous mixing model with additive Gaussian noise [1]. The inference problem is solved by ML-II, i.e. the sources are found by integration over the source posterior and the noise covariance and mixing matrix are found by maximization of the marginal likelihood [1]. The sufficient statistics are estimated by either variational mean field Theory with the linear response correction or by adaptive TAP mean field Theory [2,3]. The mean field equations are solved by a belief propagation method [4] or sequential iteration. The computational complexity is N M^3, where N is the number of time samples and M the number of sources.
標簽： instantaneous algorithm Bayesian Gaussian
上傳時間： 2013-12-19
上傳用戶：jjj0202
Beginning with an introduction to 802.11b in general, 802.11 Security gives you a broad basis in Theory and practice of wireless security, dispelling some of the myths along the way. In doing so, they provide you with the technical grounding required to think about how the rest of the book applies to your specific needs and situations. If you are a network, security, or systems engineer, or anyone interested in deploying 802.11b--based systems, you ll want this book beside you every step of the way.
標簽： 802.11 introduction Beginning Security
上傳時間： 2013-12-04
上傳用戶：CHINA526
