Computergesteuertes Datenerfassungssystem für die Schnittholztrocknung

The analysis of kiln drying with regard to energy consumption and drying quality requires the collection of extensive data. For this purpose a computer controlled data acquisition system was developed. The task of the system is to measure all the necessary values, to carry out calculations and to store data and results on magnetic discs for further processing. For better information of the user all current measured values and intermediate results are displayed on the screen. By using a computer to control the measuring cycle and the measuring devices a great flexibility is achieved. The system can easily be adapted to different measuring and evaluation tasks.     

射频激励CO2激光器功率的数字控制方法

在射频（RF）激励激光器中，功率控制大多采用脉宽调制（PWM）方式，针对PWM方式，本文提出一种采用全数字方式产生频率及占粉比可调的脉冲信号，该信号用来控制激光器的输出功率.     

W-CDMA系统中辅同步信道捕获的改进

W-CDMA系统中,各基站之间是异步时序关系。为了快速识别基站,3GPP协议引入了三步同步的小区搜索算法。第二步对辅同步信道的搜索是极其重要的。采用传统的匹配滤波器组结构运算复杂度比较大。该文分析了辅同步信道的结构,根据其构造特性提出了部分快速哈达玛变换(PFHT)的快速算法。理论分析证明该算法减少了接近70％的运算量。同时,针对辅同步信道的RS码表搜索,提出了一种分布式子图搜索算法,与穷举搜索相比,大幅度降低了复杂度。经过这两方面的改进,使辅同步信道捕获的硬件设计复杂度大大降低,对于工程应用具有重要价值。     

InAs nanowire superconducting tunnel junctions: Quasiparticle spectroscopy,thermometry, and nanorefrigeration

We demonstrate an original method based on controlled oxidation for creating high-quality tunnel junctions between superconducting Al reservoirs and InAs semiconductor nanowires (NWs).We show clean tunnel characteristics with a current suppression by ＞4 orders of magnitude for a junction bias well below the Al gap of A0 ≈ 200 μeV.The experimental data agree well with the BardeenCooper-Schrieffer theoretical expectations for a superconducting tunnel junction.The studied devices employ small-scale tunnel contacts functioning as thermometers as well as larger electrodes that provide proof-of-principle active cooling of the electron distribution in the NWs.A peak refrigeration of approximately δT =10 mK is achieved at a bath temperature of Tbath ≈ 250-350 mK for our prototype devices.This method introduces important perspectives for the investigation of the thermoelectric effects in semiconductor nanostructures and for nanoscale refrigeration.