用于准二维移动容迟容断网络的实时资源分配策略

资源分配是移动容迟容断网络的核心问题之一,影响着容迟容断网络路由甚至整个系统的效率.然而目前移动容迟容断网络的资源分配策略大多基于神经网络和遗传算法的混合算法,计算量大,不利于实时应用.为此根据移动网络可预测环境,提出了接入路由器消息矩阵及准二维接入带宽的约束条件,在此基础上建立了基于效用函数的资源分配策略,以满足实时要求.算法具有O(n)的算法复杂度,仿真结果显示切换掉话率和新呼叫阻塞率仅比最优化算法升高约1/4,计算用时则只有其36.99％.说明其在保证实时性的前提下仍能提供较好的QoS.算法可以进一步推广到二维移动场景中.     

南堡油田稠油CO_2吞吐选井模糊综合评判方法研究

二氧化碳吞吐控水增油矿场试验是南堡油田增产作业的有效技术手段,但如何选井已成为能否取得预期效果的难点,南堡油田属于复杂断块油藏,各项影响因素关系复杂,通过常规理论分析量化研究困难.提出应用层次分析法和模糊综合评判方法相结合,充分考虑地质与开发因素共18项,其中主要影响因素6项,建立稠油CO_2吞吐选井评价模型,对南堡油田区块32口稠油CO_2吞吐选井进行评价,实际增油量的回归方程拟合优度判定系数为0.7493,对于油田开发产量预测已经达到较高精度,确定模糊评判得分0.8以上即为可实行的CO_2吞吐施工方案.     

Review of flexible and transparent thin-film transistors based on zinc oxide and related materials

Flexible and transparent electronics enters into a new era of electronic technologies.Ubiquitous applications involve wearable electronics,biosensors,flexible transparent displays,radio-frequency identifications(RFIDs),etc.Zinc oxide(ZnO) and relevant materials are the most commonly used inorganic semiconductors in flexible and transparent devices,owing to their high electrical performances,together with low processing temperatures and good optical transparencies.In this paper,we review recent advances in flexible and transparent thin-film transistors(TFTs) based on ZnO and relevant materials.After a brief introduction,the main progress of the preparation of each component(substrate,electrodes,channel and dielectrics) is summarized and discussed.Then,the effect of mechanical bending on electrical performance is highlighted.Finally,we suggest the challenges and opportunities in future investigations.     

基于AAA认证的仓储移动网络安全关联转移方案

提出基于AAA认证的移动网络(NEMO)安全预接入通告方案,由无线传感器定位信息预判切换,触发安全关联等上下文转移,并告知对端节点或对端服务器的数据处理中心,提前实现安全验证。用?演算建模以保证与现有NEMO安全机制兼容。理论分析知其减少的不当路由开销可达一半,模拟显示延时和资源占用大为降低。     

CRT投影电视会聚系统的原理与设计（上）──投影电视画面失真补偿原理和实现补偿的方法

ＣＲＴ投影电视会聚系统的原理与设计（上）──投影电视画面失真补偿原理和实现补偿的方法福建日立电视机有限公司王珍琪，张永晖，张石夫随着生活水平的提高，人们对家庭生活的要求也在升格，家庭影剧院就在这种环境下发展起来。所谓家庭影剧院，顾名思义就是在家庭中设...     

A self-powered sensitive ultraviolet photodetector based on epitaxial graphene on silicon carbide

A self-powered graphene-based photodetector with high performance is particularly useful for device miniaturization and to save energy.Here,we report a graphene/silicon carbide(SiC)-based self-powered ultraviolet photodetector that exhibits a current responsivity of 7.4 m A/W with a response frequency of over a megahertz under 325-nm laser irradiation.The built-in photovoltage of the photodetector is about four orders of magnitude higher than previously reported results for similar devices.These favorable properties are ascribed to the ingenious device design using the combined advantages of graphene and SiC,two terminal electrodes,and asymmetric light irradiation on one of the electrodes.Importantly,the photon energy is larger than the band gap of SiC.This self-powered photodetector is compatible with modern semiconductor technology and shows potential for applications in ultraviolet imaging and graphene-based integrated circuits.     

Direct ZnO X-Ray Detector with Tunable Sensitivity

Direct ZnO x-ray detectors with tunable sensitivity are realized by delicately controlling the oxygen flux during the sputtering deposition process. The photocurrents induced by x-rays from a 40 kV x-ray tube with a Cu anode increase apparently as the oxygen flux decreases, which is attributed to the introduction of V_o detects.By introducing V_o defects, the annihilation rate of the photo-generated electron-hole pairs will be greatly slowed down, leading to a remarkable photoconductive gain. This finding informs a novel way to design the x-ray detectors based on abundant oxide materials.     

投影电视会聚系统的原理与设计（下）：数字式会聚调试设备的设计

投影电视会聚系统的原理与设计（下）──数字式会聚调试设备的设计福建日立电视机有限公司林涛，张永晖，王珍琪１数字式会聚调试设备工作原理在（上）文所述的“校正波形发生器”（以下简称会聚板）中，经量化后的校正波形数据存在ＥＰＲＯＭ中，配合行场扫描信号读出，...     

Enhanced photoresponse performance in Ga/Ga_2O_3 nanocomposite solar-blind ultraviolet photodetectors

In the present work, we explore the solar-blind ultraviolet(UV) photodetectors(PDs) with enhanced photoresponse,fabricated on Ga/Ga_2O_3 nanocomposite films. Through pre-burying metal Ga layers and thermally post-annealing the laminated Ga2 O3/Ga/Ga_2O_3 structures, Ga/Ga_2O_3 nanocomposite films incorporated with Ga nanospheres are obtained. For the prototype PD, it is found that the photocurrent and photoresponsivity will first increase and then decrease monotonically with the thickness of the pre-buried Ga layer increasing. Each of all PDs shows a spectrum response peak at 260 nm, demonstrating the ability to detect solar-blind UV light. Adjustable photoresponse enhancement factors are achieved by means of the surface plasmon in the nanocomposite films. The PD with a 20 nm thick Ga interlayer exhibits the best solar-blind UV photoresponse characteristics with an extremely low dark current of 8.52 p A at 10-V bias, a very high light-to-dark ratio of ～ 8 × 10~5, a large photoresponsivity of 2.85 A/W at 15-V bias, and a maximum enhancement factor of ～ 220. Our research provides a simple and practical route to high performance solar-blind UV PDs and potential applications in the field of optoelectronics.