制作基于PIC Mcu 的ADS-B接收機的全套資料，包括SCH、PCB、源碼和PC端軟件。
上傳時間： 2013-04-24
上傳用戶：cx111111
2012TI杯陜西賽題H題,2012TI杯陜西賽題B題--頻率補償電路.
上傳時間： 2013-10-07
上傳用戶：ysystc670
為了改變目前電網現場作業管理的變電巡檢、變電檢修試驗、輸電線路巡檢檢修等管理系統各自獨立運行，信息不能共享，功能、效率受限，建設和維護成本高的現狀，提出了采用B/S+C/S構架模式，將各現場作業管理模塊和生產MIS（管理系統）集成為一體的現場作業管理系統的設計方案，做到各子系統和生產MIS軟硬資源共享，做到同一數據唯一入口、一處錄入多處使用。各子系統設備人員等基礎信息來源于生產管理系統，各子系統又是生產管理系統的作業數據、缺陷信息的重要來源。經過研究試用成功和推廣應用，目前該系統已在江西電網220 kV及以上變電站全面應用。 Abstract: In order to improve the status that the substation field inspection system， substation equipments maintenance and testing system， power-line inspection and maintenance system are running independent with each other. They can?蒺t share the resource information which accordingly constrains their functions and efficiency， and their construction and maintenance costs are high. This paper introduces a field standardized work management system based on B/S+C/S mode， integrating all field work management systems based on MIS and share the equipments and employee?蒺s data of MIS，the field work data of the sub systems are the source information of MIS， by which the same single data resouce with one-time input can be utilized in multiple places. After the research and testing， this system is triumphantly using in all 220kV and above substations in Jiangxi grid.
上傳時間： 2013-11-15
上傳用戶：han_zh
PSHLY-B回路電阻測試儀介紹
上傳時間： 2013-11-05
上傳用戶：木子葉1
All inputs of the C16x family have Schmitt-Trigger input characteristics. These Schmitt-Triggers are intended to always provide proper internal low and high levels, even if anundefined voltage level (between TTL-VIL and TTL-VIH) is externally applied to the pin.The hysteresis of these inputs, however, is very small, and can not be properly used in anapplication to suppress signal noise, and to shape slow rising/falling input transitions.Thus, it must be taken care that rising/falling input signals pass the undefined area of theTTL-specification between VIL and VIH with a sufficient rise/fall time, as generally usualand specified for TTL components (e.g. 74LS series: gates 1V/us, clock inputs 20V/us).The effect of the implemented Schmitt-Trigger is that even if the input signal remains inthe undefined area, well defined low/high levels are generated internally. Note that allinput signals are evaluated at specific sample points (depending on the input and theperipheral function connected to it), at that signal transitions are detected if twoconsecutive samples show different levels. Thus, only the current level of an input signalat these sample points is relevant, that means, the necessary rise/fall times of the inputsignal is only dependant on the sample rate, that is the distance in time between twoconsecutive evaluation time points. If an input signal, for instance, is sampled throughsoftware every 10us, it is irrelevant, which input level would be seen between thesamples. Thus, it would be allowable for the signal to take 10us to pass through theundefined area. Due to the sample rate of 10us, it is assured that only one sample canoccur while the signal is within the undefined area, and no incorrect transition will bedetected. For inputs which are connected to a peripheral function, e.g. capture inputs, thesample rate is determined by the clock cycle of the peripheral unit. In the case of theCAPCOM unit this means a sample rate of 400ns @ 20MHz CPU clock. This requiresinput signals to pass through the undefined area within these 400ns in order to avoidmultiple capture events.For input signals, which do not provide the required rise/fall times, external circuitry mustbe used to shape the signal transitions.In the attached diagram, the effect of the sample rate is shown. The numbers 1 to 5 in thediagram represent possible sample points. Waveform a) shows the result if the inputsignal transition time through the undefined TTL-level area is less than the time distancebetween the sample points (sampling at 1, 2, 3, and 4). Waveform b) can be the result ifthe sampling is performed more than once within the undefined area (sampling at 1, 2, 5,3, and 4).Sample points:1. Evaluation of the signal clearly results in a low level2. Either a low or a high level can be sampled here. If low is sampled, no transition willbe detected. If the sample results in a high level, a transition is detected, and anappropriate action (e.g. capture) might take place.3. Evaluation here clearly results in a high level. If the previous sample 2) had alreadydetected a high, there is no change. If the previous sample 2) showed a low, atransition from low to high is detected now.
上傳時間： 2013-10-23
上傳用戶：copu
TKS仿真器B系列快速入門
上傳時間： 2013-10-31
上傳用戶：aix008
一個簡單好用的B+樹算法實現
上傳時間： 2015-01-04
上傳用戶：縹緲
一個用Basic實現的B-Tree算法
上傳時間： 2013-12-30
上傳用戶：ccclll
一個用Java applet實現的B-Tree算法
上傳時間： 2013-12-25
上傳用戶：qiao8960
用C++實現的B-Tree算法
上傳時間： 2014-01-20
上傳用戶：jiahao131
