Apprehend Screen Capture Component Version 4.2 A non-visible component to capture images. Freeware with source. Includes Four Demos with source and EXE s. 3,550 KB. 10/09/2005
visible light communications (VLC) is the name given to an optical wireless
communication system that carries information by modulating light in the visible spectrum
(400–700 nm) that is principally used for illumination [1–3]. The communications signal
is encoded on top of the illumination light. Interest in VLC has grown rapidly with the
growth of high power light emitting diodes (LEDs) in the visible spectrum. The
motivation to use the illumination light for communication is to save energy by exploiting
the illumination to carry information and, at the same time, to use technology that is
“green” in comparison to radio frequency (RF) technology, while using the existing
infrastructure of the lighting system.
A light-emitting diode (LED) is a semiconductor device that emits narrow-spectrum incoherent light when forward-biased.The color of the emitted light depends on the chemical composition of the semiconductor material used, and can benear-ultraviolet, visible or infrared. LEDs are more prevalent today than ever before, replacing traditional incandescent andfluorescent bulbs in many lighting applications. Incandescents use a heated filament, are subject to breakage and burnoutand operate at a luminous efficiency of 2% to 4%. Fluorescents are more efficient, at 7% to 12%, but require highdrive voltage and contain mercury, a toxic substance that may be eventually banned in certain countries. LEDs, however,produce light directly through electroluminescence, operate at low voltage and can deliver over 20% luminous efficiency.
介紹一種基于C8051單片機的動態心電監護系統。該系統由兩部分組成:以C8051F320單片機為核心的數據采集裝置和以PC機為平臺的分析處理系統。硬件電路功耗低,由單片機自帶的USB接口將數據傳送給PC機。軟件平臺采用LabVIEW可視化虛擬儀器系統開發平臺,將傳統儀器的功能模塊集成到計算機中,用戶可通過修改虛擬儀器的程序改變其功能。采用USB接口實時傳輸心電數據,并將數據采集模塊設計為計算機外設,使該系統高速快捷、小巧便攜。
Abstract:
In this design,a low-cost ECG electrocardiogram monitoring system is introduced,which consists of two parts:data acquisition device based on C8051F320and PC terminal as the analysis and processing system.The system is low-power consumption,the data is transmitted to the PC terminal by USB interface of the C8051F320.By using the visible virtual instrument system developing platform LabVIEW,the traditional instruments function modules are integrated into the computer,so the user can modify virtual instrument software to change its function to meet their needs.Using USB in-terface to realize real-time ECG data transmission,in addition,ECG data acquisition module is designed as the computer peripheral,which makes the syetem high-speed and portable.