基于嵌入式的智能流速仪研制

流速仪为水工筑建设计提供准确的江河的流速值,随着应用需求的增加,原有的8位单片机控制系统不能完全满足现代水文测量的需要。本文研制了一种旋桨式传感器的智能流速仪,以AT91SAM9261为微处理器,采用CPLD芯片为流速数据采集接口,配以TFT-LCD显示屏,移植uClinux实时操作系统,具有测周、计数、双向测速等多种测量方式,可实现16个通道同步独立检测。系统测量方式灵活,测量时间短,测量精度高,稳定可靠等特点,广泛用于水文检验部门和科研设计院等单位。     

传输故障处理经验总结

处理传输故障的关键是故障的准确定位。为了达到这个目标,需要在维护时清楚故障定位的原则、排查故障的可能原因,掌握一种高效的手段或方法来迅速处理可能遇到的各种故障。     

一种基于家宽网络故障与业务的精准关联技术

在运营商故障监控工作中,OLT退服告警对宽带业务影响范围、家宽实际影响用户数一直是家宽业务关联影响的重要环节,明确OLT退服影响是告警监控重要的目标。提出一种基于家宽网络故障与业务的精准关联技术,将家宽用户信息与告警相结合,实现故障与影响客业务的网络指标自动关联,完成对OLT退服对业务的影响、影响用户精准分析和用户投诉的分析关联,减少用户投诉,提升用户满意度,实现经济效益的提升。     

Bioinspired Supramolecular Slippery Organogels for Controlling Pathogen Spread by Respiratory Droplets

Surface-deposited pathogens are sources for the spread of infectious diseases. Protecting public facilities with a replaceable or recyclable antifouling coating is a promising approach to control pathogen transmission. However, most antifouling coatings are less effective in preventing pathogen-contained respiratory droplets because these tiny droplets are difficult to repel, and the deposited pathogens can remain viable from hours to days. Inspired by mucus, an antimicrobial supramolecular organogel for the control of microdroplet-mediated pathogen spread is developed. The developed organogel coating harvests a couple of unique features including localized molecular control-release, readily damage healing, and persistent fouling-release properties, which are preferential for antifouling coating. Microdroplets deposited on the organogel surfaces will be spontaneously wrapped with a thin liquid layer, and will therefore be disinfected rapidly due to a mechanism of spatially enhanced release of bactericidal molecules. Furthermore, the persistent fouling-release and damage-healing properties will significantly extend the life-span of the coating, making it promising for diverse applications.     

Nitrate Additives Coordinated with Crown Ether Stabilize Lithium Metal Anodes in Carbonate Electrolyte

Lithium metal anodes (LMAs) are promising for next-generation batteries but have poor compatibility with the widely used carbonate-based electrolytes, which is a major reason for their severe dendrite growth and low Coulombic efficiency (CE). A nitrate additive to the electrolyte is an effective solution, but its low solubility in carbonates is a problem that can be solved using a crown ether, as reported. A rubidium nitrate additive coordinated with 18-crown-6 crown ether stabilizes the LMA in a carbonate electrolyte. The coordination promotes the dissolution of NO₃⁻ ions and helps form a dense solid electrolyte interface that is Li₃N-rich which guides uniform Li deposition. In addition, the Rb (18-crown-6)⁺ complexes are adsorbed on the dendrite tips, shielding them from Li deposition on the dendrite tips. A high CE of 97.1% is achieved with a capacity of 1 mAh cm⁻² in a half cell, much higher than when using the additive-free electrolyte (92.2%). Such an additive is very compatible with a nickel-rich ternary cathode at a high voltage, and the assembled full battery with a cathode material loading up to 10 mg cm⁻² shows an average CE of 99.8% over 200 cycles, indicating a potential for practical use.     

基于信捷PLC对细石混凝土泵电气系统的设计

为了推进细石混凝土泵的国产化,在保证产品性能的前提下,降低其电气系统的生产成本,采用以国产信捷PLC(Programmable Logic Controller)为主的控制元件对细石混凝土泵电气系统进行了设计。在保证细石混凝土泵使用稳定性的同时,降低了其电气系统的制造成本,提高了适用性。所设计电气系统经菏泽永安机械制造有限公司检验使用,实际应用情况良好。     

Performance Evaluation of IEEE 802.15.4 CSMA/CA Scheme Adopting a Modified LIB Model

Since the successful release of the IEEE 802.15.4 standard, a great convenience is offered to applications in low-power and low-rate wireless sensor networks (WSNs) which almost touch upon all aspects in our surrounding circumstances. For time-critical applications, we use a modified Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) mechanism called Linear Increase Backoff (LIB) to enhance the performance of packet delay, but not compromise the metrics of energy efficiency and throughput. An accurate and comprehensive Markov model is used to analyze the characteristics of our LIB scheme predicting packet delay, energy consumption and throughput of unsaturated, unacknowledged IEEE 802.15.4 networks in which the unsaturated state is dependent on the traffic condition rather than the depiction by a predetermined length. Simulation results are consistent with the predictions of this model. We also compare the performance of LIB with that of several mechanisms according to the optimal parameters selected from operating point, and find that packet delay is obviously superior to that of other schemes, while energy efficiency and throughput are superior to others for large number of nodes and high traffic arrivals.     

我国固定网本地环路分拆问题的探讨

我国电信业新的竞争格局和宽带接入需求的增长推动了固定本地网领域的竞争。本地环路分拆有助于促进竞争同时减少重复建设。本文介绍了本地环路分拆的概念，对我国实施本地环路分拆的必要性进行了论述，并借鉴其他国家的实施经验，对我国实施本地环路分拆的监管政策提出了建议。     

585nm脉冲染料激光治疗皮肤血管性疾病所致的副作用

目的:观察585nm脉冲染料激光治疗血管性疾病所致的副作用。方法:分析500例经585nm脉冲染料激光治疗后的副反应。结果:500例接受治疗的患者中发生副反应者89例。其中色素沉着35例、色素减退12例、萎缩性瘢痕40例、增生性瘢痕2例。出现副反应与疾病种类、治疗能量无关,与治疗次数有关。结论:585nm脉冲染料激光治疗血管性疾病无连续激光治疗后所致的增生性瘢痕、持续性色素沉着等副作用,用于治疗血管性疾病是比较安全的。