井口信号无线数传系统

目的：介绍了井口信号无线数系统的设计，方法，无线数传、低功耗电路设计，结果：省去了井口信号线，降低了井口工作量。结论：提高了测量精度和可靠性。     

基于C8051单片机的多路温度无线遥测系统

基于C8051F020单片机和DTD465无线数传模块设计了多路温度双向无线遥测系统.温度测量采用铂电阻;无线数传模块基于FSK调制,采用高效前向纠错信道编码技术;系统为低功耗设计.介绍了测量站和主控站的软件,以及数据通信协议.系统已成功地应用于汽车导航实验中,使用结果表明,本系统软硬件设计完善,可靠性高,使用方便.     

高炉上料监测系统的远程数据无线传送技术

针对在高温环境下对冶炼高炉上料数据实施监控的用户要求,开发了一种基于无线数传模块的远端数据采集传送装置.现场数据采集后通过无线数传模块与上位机进行通信,上位机接收数据并监控工作状况,历史数据可以具备存储、查询、报表等功能.经过实际运行测试,说明利用无线数传模块可以进行冶炼高炉特殊环境下计量测试、数据通讯及远端控制,尤其适用于下位机组成基于现场总线的监控网络,而上位机移动或多点上位机的使用场合.     

3G无线数传在厂矿企业中的应用

随着厂矿企业生产自动化程度的不断提高,工业现场对各种数据信号的采集及传输有了更高的要求,特别对于终端数据采集及传输,从有线到无线、从有人值守到无人操作的转变已成趋势。利用无线数传系统将现场设备输出的数据或者各种物理量进行远程传输到后方进行集中处理,已经得到十分广泛的应用,随着科学技术的发展,无线传输的方式也在不断变化。本文通过对3G无线数传技术在铁水运输调度跟踪系统中应用的介绍,探讨了3G通信技术在无线数据传输中应用的可行性,为今后3G无线数传在厂矿企业规模化应用提供借鉴。     

基于STM32和无线数传模块的远程环境监控系统设计

传统的环境监控大多采用有线数据传输,因此接入的数据线比较多,安装难度也较大,监控距离也会受到数据线长度的影响。为了弥补这些不足,该文利用STM32F103主控芯片和无线数传模块设计了一个具有无线联网功能的远程监控系统。该系统可以采集多点远程环境数据,采用无线模式在GPRS网络环境下传输数据,将数据上传到原子云服务器,原子云服务器将数据反馈到控制中心进行数据分析,根据分析的结果对远程终端通过无线数传模块进行控制。     

基于nRF903的无线数传模块设计

本文介绍了采用nRF903和P89LPC932构成的无线数传模块,该模块接口电路简单可靠,并能实现低功耗工作。可适用于无线通信系统。     

井口数据无线传输技术在作业区的应用

气田的气井基本位于沙漠和黄土塬地区,气井分散密布与作业区区部和集气站距离远,气井日常巡护的工作量大,井口生产数据无法及时传达给各集气站,进行气井井口数据采集及无线传输技术的试验,集气站可以随时读取井口数据,大幅度地减少巡井工作量,降低车辆出车次数,提高气井管理水平.     

基于nRF903的无线倾斜度测量系统

文中介绍了一种以nRF903无线数传芯片为核心,利用集成倾角传感器和温度传感器设计出带有温度补偿功能的倾角测量系统硬件电路,并以S3C2410为核心设计出数据接收终端,对数据进行处理.该系统稳定性好,通信效率高,可广泛应用于工业现场测控领域.     

STC89C52单片机实现多路无线防盗报警系统

主要论述利用STC89C52单片机实现多路无线防盗报警系统。主机可监控从机(报警器)的开启与关闭,当从机检测到入侵时报警,并通过无线传输报告给主机。系统地阐述STC89C52单片机与热释电红外传感器模块、DF无线数传模的接口及工作原理。     

数传手持遥控系统设计

本文以LPC932A1单片机为控制核心,设计了一款应用于水平输送机控制的数传手持遥控设备,其能够实现输送机的启动／停车、传送方向和传送速度等参数的实时控制。该装置主要有键盘、LCD显示模块、无线数据传输模块和主控制器及相关外围电路组成。该数传手持遥控器稳定可靠、功耗低且节省人力成本,能够提高工作效率。     

无线 ATM 网络越区切换的改进方案和性能分析

目的提出一种实用于 WATM 网络的越区切换方案. 方法在分析 WATM 控制结构的基础上, 所提出的适应 WATM 的越区方案, 支持网络环境中的频繁切换事件, 同时采用有效的用户呼叫控制机制, 使越区切换产生的小区超载现象发生概率保持在可接受的限度内. 结果与结论该方案不仅提高了性能, 而且还可以降低通信设备成本.     

Conditions for complete self-healing breakdown in glow discharge polymerized styrene films

Breakdown patterns of glow discharge polymerized styrene film sandwiched between the top and base electrodes and fabricated on a glass substrate have been observed with a microscope. The breakdown patterns can be classified into three types: a broad ring of partly vanishing top electrode metal occuring around the breakdown hole in the dielectric (type A); a large hole made through the three layers (one dielectric and two metal layers), the dielectric film and the top electrode being folded back together at the periphery of the hole and the base electrode being melted over the hole area (type B); successive breakdown around the periphery of previous breakdown spots (type P). These patterns are interpreted in terms of the action of an arc across an extremely short gap as well as joule heating. Type A is preferable for attaining complete self-healing and the conditions that most favour the occurrence of type A holes are (a) the application of a positive voltage to the top electrode and (b) the top electrode being thin compared with the base electrode.     

灰铸铁和球墨铸铁前托架钻削性能评价

从导热系数、铁屑形貌、钻孔内表面粗糙度、钻头顶部温度、钻削负载(扭矩、进给力)等方面,评价了QT450和HT250材质拖拉机前托架的钻削性能,并分析了钻削性能与微观组织的关系。结果表明,对HT250和QT450前托架钻削加工时,两者钻削负载没有明显差别;与HT250相比,QT450的石墨对基体的分割作用小,其基体组织中较多的铁素体,造成钻削加工时断屑和排屑困难,导致钻孔内表面粗糙度大;QT450导热系数低、铁屑与钻头摩擦严重,使得钻头温度较高;QT450有较小的切削力和铁屑对钻头较大的摩擦力,在这2个力作用下,QT450钻削负载与HT250基本相同。     

Highly Efficient and Bright Inverted Top‐Emitting InP Quantum Dot Light‐Emitting Diodes Introducing a Hole‐Suppressing Interlayer

InP quantum dots (QDs) based light‐emitting diodes (QLEDs) are considered as one of the most promising candidates as a substitute for the environmentally toxic Cd‐based QLEDs for future displays. However, the device architecture of InP QLEDs is almost the same as the Cd‐based QLEDs even though the properties of Cd‐based and InP‐based QDs are quite different in their energy levels and shapes. Thus, it is highly required to develop a proper device structure for InP‐based QLEDs to improve the efficiency and stability. In this work, efficient, bright, and stable InP/ZnSeS QLEDs based on an inverted top emission QLED (ITQLED) structure by newly introducing a “hole‐suppressing interlayer” are demonstrated. The green‐emitting ITQLEDs with the hole‐suppressing interlayer exhibit a maximum current efficiency of 15.1–21.6 cd A^?1 and the maximum luminance of 17 400–38 800 cd m^?2, which outperform the recently reported InP‐based QLEDs. The operational lifetime is also increased when the hole‐suppressing interlayer is adopted. These superb QLED performances originate not only from the enhanced light‐outcoupling by the top emission structure but also from the improved electron–hole balance by introducing a hole‐suppressing interlayer which can control the hole injection into QDs.     

Black Hole and Sink Hole Attack Detection in Wireless Body Area Networks

In Wireless Body Area Networks (WBANs) with respect to health care, sensors are positioned inside the body of an individual to transfer sensed data to a central station periodically. The great challenges posed to healthcare WBANs are the black hole and sink hole attacks. Data from deployed sensor nodes are attracted by sink hole or black hole nodes while grabbing the shortest path. Identifying this issue is quite a challenging task as a small variation in medicine intake may result in a severe illness. This work proposes a hybrid detection framework for attacks by applying a Proportional Coinciding Score (PCS) and an MK-Means algorithm, which is a well-known machine learning technique used to raise attack detection accuracy and decrease computational difficulties while giving treatments for heartache and respiratory issues. First, the gathered training data feature count is reduced through data pre-processing in the PCS. Second, the pre-processed features are sent to the MK-Means algorithm for training the data and promoting classification. Third, certain attack detection measures given by the intrusion detection system, such as the number of data packages trans-received, are identified by the MK-Means algorithm. This study demonstrates that the MK-Means framework yields a high detection accuracy with a low packet loss rate, low communication overhead, and reduced end-to-end delay in the network and improves the accuracy of biomedical data.     

Implication of Striped Hole Structurization on the Evolution of Cuprate Electronic Properties with Doping

The striped hole structurization in cuprate CuO₂ layers is discussed in the framework of the earlier introduced string model implying the direct overlap of O 2p-like orbitals. In the lightly doped compounds with the mean hole density , each dopant ion and the nearest quantized hole orbital of rank η can be viewed as a pseudoatom. The growth of above 1/24 stimulates condensation of the pseudoatoms into pancakes where some part of hole orbitals is expected to be collectivizing into bosonic stripes (BS). The formation of BS among the fermion-like hole surroundings has to be displayed in electronic spectra first as a bulge, and then as the coherent peak flanking to the broad hump of incoherent origin (the so called “peak-dip-hump structure”). Accumulating and broadening BS with increase of give rise to percolation superconductivity below a border of critical temperatures . It is shown, that the cuprate characteristics calculated without fitting parameters are consistent with measurements.      

染料敏化纳米薄膜太阳能电池的研究进展

本文简要地介绍了染料敏化纳米薄膜太阳能电池的结构和原理 ;对其中关键问题 ,如纳米TiO2膜、敏化染料、空穴传输材料的研究进展进行了综述     

顶部空气间隔装药对岩石爆破块度影响的试验研究

空气间隔装药方式能够改变爆炸能量的分布,顶部空气间隔装药方式是提高炮孔顶部的岩石破碎效果的主要方式之一。通过理论和现场试验分析顶部空气间隔对岩石破碎块度的影响,顶部空气间隔的存在可以有效地改变爆生气体和冲击波在空气隔层中的作用方向;现场试验表明,空气间隔比例10%时平均块度和无空气间隔的平均块度接近,空气间隔比例25%时产生最大平均块度。得到的合理空气间隔比例为10%～15%。     

Fluorescence in the presence of metallic hole arrays

We show that the transmission of light through metallic hole arrays supported by a glass substrate can be tuned by depositing a controlled number of Langmuir–Blodgett layers on top of the hole array. Enhanced transmission is achieved when the number of overlayers is such that the surface plasmon-polariton modes on the two sides of the metal hole array have matched wavevectors. Dye molecules introduced into some of these overlayers allow us to explore the relationship between molecular fluorescence and the transmission properties of the structure, through measurement of the fluorescence lifetime of the molecules. We find there to be little change in the fluorescence lifetime between enhanced and non-enhanced transmission regimes and offer an explanation of our findings in terms of changes in the photonic mode density.     

166.6 MHz超导腔加强筋结构的多物理场耦合仿真

高能同步辐射光源加速器的166.6 MHz超导腔采用4.5K饱和液氦浸泡冷却,其内导体与小束管之间设计有加强筋以改善超导的应力分布,加强筋会影响气泡排出,气泡聚集过多会降低液氦冷却效果,有引发失超的风险.使用Fluent、Hfss软件对超导腔内导体附近的流场进行了流动/传热/电磁多物理场耦合仿真,研究了加强筋顶部开孔设...