按需式ad hoc移动网络路由协议的研究进展

Ad hoc移动网络是一种完全由移动主机构成的网络，网络拓扑易变，带宽，能源有限是ad hoc移动网络的主要特点，针对这些特点，目前设计的ad hoc路由协议大多采用按需查找方式，该文介绍了这方面研究的最新进展，对几种典型的按需路由协议进行了说明，分析和综合比较，文中分析了目前协议存在的一些问题并提出了相应的改进方法，最后指出了下一步研究方向。     

Rigorous TE solution to the dielectric wedge antenna fed by a slab waveguide

A rigorous TE solution to the dielectric wedge antenna fed by a slab waveguide of the same material is presented. The method of solution involves modeling the wedge as a sequence of step discontinuities and uses an iterative procedure to track forward and backward partial wave fields, expressed as modal expansions, to obtain the rigorous field solution. Radiation patterns of directive gain are presented. All patterns smoothly decrease from a maximum in the endfire direction and exhibit extremely low side lobe levels. Longer length wedges or smaller dielectric constant materials are shown to produce higher directivity and smaller half-power beamwidths. For slender, gradually tapered wedges, the reflection coefficient of the guided (surface) wave at the input to the wedge is very small indicating a low VSWR for tapered dielectric antennas and there appears to be no gain limitation with antenna length for these antennas.     

单向ad-hoc移动网络优化路由协议OUAOR

ad-hoc移动网络是一种完全由移动主机构成的网络，该文基于作者设计的单向ad-hoc移动网络路由协议UAOR，提出了优化受限查找，双向链路感知和按需维护的单向路由协议OUAOR。和UAOR相比，OUAOR具有路由查找和维护控制开销小，网络扩展性高，路由查找的初始延迟低等特点。该文证明了OUAOR协议的正确性，并给出了模拟实验分析数据。     

The effect of an Al underlayer on Fe–Si thin film catalysts for the improved growth of carbon nanotubes

We report the positive effect of an Al underlayer for enhancing the growth of carbon nanotubes (CNTs) on Si substrates. The catalyst used for the growth was a sputter-deposited Fe–Si thin film and the growth temperature was 370 °C. The morphology, composition, microstructure, and crystalline structure of the Fe–Si films with and without an Al underlayer having different thicknesses were examined. Correlation between the Al underlayer thickness and the film characteristics is made. The effect of Al thickness on the growth of CNTs is discussed. It was found that the maximum growth increase occurs at an Al thickness of 4 nm, for which the growth is increased by 220%.     

Adaptive personalized recommendation based on adaptive learning

Collaborative filtering has been widely applied in many fields in recent years due to the increase in web-based activities such as e-commerce and online content distribution. Current collaborative filtering techniques such as correlation-based, SVD-based and supervised learning-based approaches provide good accuracy, but are computationally very expensive and can only be deployed in static off-line settings, where the known rating information does not change with time. However, a number of practical scenarios require dynamic adaptive collaborative filtering that can allow new users, items and ratings to enter the system at a rapid rate. In this paper, we consider a novel adaptive personalized recommendation based on adaptive learning. Fast adaptive learning runs through all the aspects of the proposed approach, including training, prediction and updating. Empirical evaluation of our approach on Movielens dataset demonstrates that it is possible to obtain accuracy comparable to that of the correlation-based, SVD-based and supervised learning-based approaches at a much lower computational cost.     

In Vitro and in Vivo Evaluation of Lactoferrin-Conjugated Liposomes as a Novel Carrier to Improve the Brain Delivery

In this study, lactoferrin-conjugated PEGylated liposomes (PL), a potential drug carrier for brain delivery, was loaded with radioisotope complex, ^99mTc labeled N,N-bis(2-mercaptoethyl)-N′,N′-diethylethylenediamine (^99mTc-BMEDA) for in vitro and in vivo evaluations. The hydrophilicity of liposomes was enhanced by PEGylation which was not an ideal brain delivery system for crossing the blood brain barrier (BBB). With the modification of a brain-targeting ligand, lactoferrin (Lf), the PEGylated liposome (PL) might become a potential brain delivery vehicle. In order to test the hypothesis in vitro and in vivo, ^99mTc-BMEDA was loaded into the liposomes as a reporter with or without Lf-conjugation. The mouse brain endothelia cell line, bEnd.3 cells, was cultured to investigate the potential uptake of liposomes in vitro. The in vivo uptake by the mouse brain of the liposomes was detected by tissue biodistribution study. The results indicated that Lf-conjugated PEGylated liposome showed more than three times better uptake efficiency in vitro and two-fold higher of brain uptake in vivo than PEGlyated liposome. With the success of loading the potential Single Photon Emission Tomography (SPECT) imaging probe, ^99mTc-BMEDA, Lf-PL might serve as a promising brain delivery system for loading diagnostics or therapeutics of various brain disorders.     

Low temperature, non-isothermal growth of carbon nanotubes

Non-isothermal growth of carbon nanotubes (CNTs) was studied in order to obtain the activation energy. CNTs were grown on an Fe-Si catalyst using microwave plasma-enhanced chemical vapor deposition of CH₄. During the growth, the substrate was heated by the plasma such that its temperature increased with the growth until equilibrium was reached. In other words, the CNT growth took place under simultaneously increased time and temperature. This has resulted in different growth kinetics from previously published studies. We have therefore examined the growth kinetics using an empirical function for CNTs grown on three different substrates and derived the relevant activation energies based on the empirical function.     

Thermal-Mechanical Process Simulation of an Advanced NCF Technology

The paper introduces an advanced nonconductive film (NCF) typed FC technology employing a novel compliant composite interconnect structure. The interconnect reliability and bondability of the technology are demonstrated through experimental thermal humidity (TH) test in conjunction with a two-point daisy chain resistance measurement. The alternative goal of the study aims to look into the insight of the thermal-mechanical behaviors of the novel packaging technology during NCF bonding process and thermal testing through numerical modeling and experimental validation. For effectively simulating the bonding process, a process-dependent finite-element (FE) simulation methodology is performed. The validity of the proposed methodology is verified through several experimental methods, including a Twyman-Green (T/G) interferometry technique for warpage measurement, and a four-point probe method for contact resistance measurement. At last, a design guideline for improved process-induced thermal-mechanical behaviors is presented through parametric FE analysis. Both numerical and experimental results demonstrate the feasibility in applying the novel compliant interconnects to achieve a proper contact stress at various temperature environments so as to hold a low and stable connection resistance at elevated temperature. Most importantly, the novel interconnects survive the 85degC/85%RH TH test for 500 hours.