428XL仪器与枪控同步器GCSlink联机详解及故障排除

本文通过428XL仪器与枪控同步器GCSlink的联机详解,系统描述了在联机时仪器和同步器的硬件连接、参数设置、采集时序以及各种参数之间的关系,兼有理论解释和实际设置。通过故障实例,证实了联机的重要性。在OBC勘探时,其它型号的仪器与控制同步器的联机,均可参考本文阐述的理论和连接方法。

QoS Adaptive Topology Configuration in Synchronous Wireless Sensor Networks

By using hyper-graph theory,this paper proposes a QoS adaptive topology configuration(QATC) algorithm to effectively control large-scale topology and achieve robust data transmitting in synchronous wireless sensor networks.Firstly,a concise hyper-graph model is abstracted to analyze the large-scale and high-connectivity network.Secondly,based on the control theory of biologic 'Cell Mergence',a novel self-adaptive topology configuration algorithm is used to build homologous perceptive data logic sub-network ...

Several solutions of remote transmission for state monitoring of bridges

The research for remote monitoring of bridges is expected to develop methodologies and tools for collecting state data, monitoring the real-time status of the bridge from distance, and more importantly seeking a best way for remote transmission of bridge monitoring system by comparing the characteristics of each scheme. This paper focuses on the solutions to remote transmission for state monitoring of bridges, which deals with the remote transmission system based on PSTN (Public Service Telephone Network), wireless sensor monitoring system and remote transmission using SDH (Synchronous Digital Hierarchy) network. As a result, a combination of wireless sensor monitoring system and the remote sensing system using SDH network is proposed to be the considered way for remote state monitoring of bridges.

FPGA Based Wireless Multi-Node Transceiver and Monitoring System

In recent years the variety and complexity of Wireless Sensor Network （WSN） applications, the nodes and the functions they are expected to perform have increased immensely. This poses the question of reducing the time from initial design of WSN applications to their implementation as a major research topic. RF communication programs for WSN nodes are generally written on microcontroller units （MCUs） for universal asynchronous receiver/transmitter （UART） data communication, however nowadays radio frequency （RF） designs based on field-programmable gate array （FPGA） have emerged as a very powerful alternative, due to their parallel data processing ability and software reconfigurability. In this paper, the authors present a prototype of a flexible multi-node transceiver and monitoring system. The prototype is designed for time-critical applications and can be also reconfigured for other applications like event tracking. The processing power of FPGA is combined with a simple communication protocol. The system consists of three major parts： wireless nodes, the FPGA and display used for visualization of data processing. The transmission protocol is based on preamble and synchronous data transmission, where the receiver adjusts the receiving baud rate in the range from min. 300 to max. 2400 bps. The most important contribution of this work is using the virtual PicoBlaze Soft-Core Processor for controlling the data transmission through the RF modules. The proposed system has been evaluated based on logic utilization, in terms of the number of slice flip flops, the number of 4 input LUTs （Look-Up Tables） and the number of bonded lOBs （Input Output Blocks）. The results for capacity usage are very promising as compared to other similar research.

外刊纵览

在风靡一时的转基因食品因化肥、农药等环保问题而备受非议时.以色列科学家NachumKedar发明了一种名叫“聪明喂养”(Smartbreeding)的水果栽培新技术。应用这种技术他培育出西红柿的新品种——Flavr Savr。“聪明喂养”技术解决了过去人们在水果采摘和储藏问题上的难题.既保持了营养又改良了口味。

Effective spectral index properties for Fermi blazars

Blazars are a special subclass of active galactic nuclei with extreme observation properties. This subclass can be divided into two further subclasses of flat spectrum radio quasars(FSRQs) and BL Lacertae objects(BL Lacs) according to their emission line features. To compare the spectral properties of FSRQs and BL Lacs, the 1.4 GHz radio, optical R-band, 1 keV X-ray, and 1 GeVy-ray flux densities for 1108 Fermi blazars are calculated to discuss the properties of the six effective spectral indices of radio to optical(α_(RO)), radio to X-ray(α_(RX)), radio to y ray(α_(Ry)), optical to X-ray(α_(OX)), optical to y ray(α_(Oy)), and X-ray to y ray(α_(Xy)).The main results are as follows: For the averaged effective spectral indices, α_(OX_> α_(Oy)> α_(Xy)> α_(Ry)> α_(RX)> α_(RO) for samples of whole blazars and BL Lacs; α_(Xy)≈α_(Ry)≈α_(RX) for FSRQs and low-frequency-peaked BL Lacs(LBLs); and α_(OX)≈α_(Oy)≈α_(Xy) for high-synchrotron-frequency-peaked BL Lacs(HBLs). The distributions of the effective spectral indices involving optical emission(α_(RO), α_(OX), and α_(Oy)) for LBLs are different from those for FSRQs, but if the effective spectral index does not involve optical emission(α_(RX), α_(Ry), and α_(Xy)), the distributions for LBLs and FSRQs almost come from the same parent population. X-ray emissions from blazars include both synchrotron and inverse Compton (IC) components; the IC component for FSRQs and LBLs accounts for a larger proportion than that for HBLs; and the radiation mechanism for LBLs is similar to that for FSRQs, but the radiation mechanism for HBLs is different from that for both FSRQs and LBLs in X-ray bands. The tendency of α_(Ry) decreasing from LBLs to HBLs suggests that the synchrotron self-Compton model explains the main process for highly energetic y rays in BL Lacs.