European atmospheric pollution imported by cooler air masses to the Eastern Mediterranean during the summer

In this study we combine Pb isotopes, Pb, Ni, Cu, Zn, and several major metal concentrations, identification of the aerosol particles, and synoptic and back trajectory analyses to obtain direct evidence for the extent and nature of mixing between Middle Eastern and European sources emissions of metals and aerosols. During the summer months aerosols collected in Israel are highly polluted by metals (EF(Ni) = 120, EF(Cu) = 320, EF(Zn) = 30, EF(Pb) = 540; average values). The fraction of European Pb of mostly industrial sources is 61 +/- 21% in Jerusalem, and the fraction of European Cu, Zn, Ni, and aerosols should be on the same order. Whenever a steep pressure gradient is built between the barometric trough originating from the Persian Gulf and the subtropical ridge along the African coast, stronger westerly winds and cooler temperatures (deep Persian Trough) prevail overthe Middle East, and higher amounts of European pollution are observed in the atmosphere (74 +/- 13%). On the other hand, when the Persian Trough is in its shallow mode, the proportion of European pollution is lower (45 +/- 18%, based on Pb isotopes). This study demonstrates that atmospheric pollution over the East Mediterranean region during the summer is influenced not only by local atmospheric dispersion conditions but also by the ability of the atmosphere to inherit a significant proportion of pollutants from European sources.     

基于SUSAN和改进的Snake模型的空中目标图像分割

文中提出一种基于SUSAN和改进的Snake模型相结合的算法,用以进行空中目标在图像中的检测和分割.首先使用SUSAN算子检测飞行器的角点,通过连接已检测出的角点形成Snake模型初始轮廓,然后用改进的Snake算子进行目标轮廓拟合.实验结果表明,该方法可以有效地进行空中目标的检测和分割,并且克服传统Snake 模型易漂移和过收敛等缺点.     

立式橡胶瓦水导轴承机组大修时导轴承间隙计算

轴线处理及导轴承间隙计算与调整是水轮发电机组安装或检修中的一项重要工作,直接影响机组安全运行。上犹江水电厂水导轴承是水润滑橡胶瓦轴承,大修时水导轴承间隙调整质量决定了机组运行时的振动和摆度。图1幅,表7个。     

The use of a rotating cylinder electrode to recover zinc from rinse water generated by the electroplating industry

This work concerns the application of a laboratory scale rotating cylinder electrode (RCE) to recover zinc from rinse water generated by the electrolytic zinc process (initially 1,300, 4,400, 50, 20 mg L(-1) of Zn(II), Fe(III), Ag(I) and Cr(VI), respectively, at pH 2), although it is also applicable to other electroplating industries. Experimental results demonstrated the convenience of the removal of ferric ions, as (Fe(OH)(3(s))) by a pH adjustment to 4, before zinc electro recovery on the RCE. The generation of smooth zinc deposits on the RCE was obtained at Reynolds numbers within the range of 15,000 ≤ Re ≤ 124,000 and limiting current densities (J(L)) in the interval of -4.8 to -13 mA cm(-2). The zinc recovery reached a conversion of 67% in 90 min of electrolysis for Re = 124,000 and J = -13 mA cm(-2), 21% current efficiency, and energy consumption of 9.5 kWh m(-3). The treated solution can be recycled back through the same rinsing process.     

30-Msamples/s programmable filter processor

A 30-MHz finite impulse response (FIR) programmable filter processor that has been developed using a 1.2-μm CMOS EPROM technology with single metal is discussed. Its 30-MHz worst-case operating frequency meets most video filtering requirements and demonstrates the potential of nonvolatile memory technologies in embedded applications. The processor has been designed with a high level of parallelism and pipelining by using a transposed FIR structure. In this approach, the multipliers are implemented with an EPROM-based look-up table containing the results of the products between video samples and filter coefficients, according to the user's application. The chap can implement every kind of FIR filter with a maximum complexity of 59 taps in a half-band filter configuration, 32 taps for a symmetric filter, and 167 taps for an asymmetric one. The equivalent coefficient precision is 12 b, assuming 8 b of input data precision. Multiprocessor configurations are allowed for more demanding performances such as longer filters, input signal precision extension, two-dimensional processing, and increased throughput     

基于AVR单片机的LED显示屏的灰度设计与实现

设计了一种基于AVR单片机的LED灰度显示屏系统,该系统采用PC机—主控单元—显示子模块3级模式,其中PC机用于更新信息数据,显示子模块用于灰度显示控制,主控单元是PC机与显示子模块的桥梁。利用AVR单片机自身的内部数据存储能力,结合其软件扫描控制能力及高速运算能力,通过调节驱动LED的脉冲电流的占空比的方式解决了LED显示屏的灰度显示控制。给出了系统的软、硬件实现方案。