基于矩阵的Apriori改进算法研究

针对关联规则中Apriori算法的不足之处,提出两种基于矩阵的Apriori改进算法.改进算法充分利用矩阵这一工具,以大幅度减少扫描数据库的次数和计算成本,进而有效提高算法的运算效率.同时,通过实例应用和算法性能分析证明所提出的两种改进算法都是有效的关联规则挖掘方法,且比Apriori算法具有更好的性能.     

关联规则挖掘 Apriori 算法的研究与改进

针对传统Apriori算法的不足之处,提出两种Apriori改进算法,分别基于构造辅助表和项集求交集策略。改进算法大幅度减少扫描数据库的次数,缩减对不必要事务的扫描时间,显著提高频繁项集的生成效率,从而使算法达到更高的运算效率。实验结果表明,两种改进算法都是有效的关联规则挖掘方法,且比Apriori算法性能更优,亦为关联规则挖掘研究提供了一些科学可行的新思路。     

改进的基于两个矩阵的关联规则挖掘算法

Apriori及其改进算法可以归为基于SQL和基于内存两类,为提高关联规则挖掘效率,在分析了一部分第二类算法存在效率瓶颈的基础上,提出了一种高效的改进算法。算法引入两个矩阵,一个矩阵用以映射数据库,另一个用作存储频繁2-项集相关信息,通过对两个矩阵的操作,使得算法时间复杂度明显降低。验证明,算法具有较好的性能。     

大数据场景下基于机器学习的5G云网告警关联分析

提出一种基于关联规则挖掘算法的5G云网告警分析方案,对机器学习算法FP-Growth进行契合5G云网告警场景的改进和应用,利用现网告警数据展开告警关联分析工作,挖掘网元及云侧告警之间的关联关系,并进行告警压缩和收敛,为5G云网故障分析和定位提供有效帮助。此外,基于实际告警数据对Apriori和FP-Growth算法的性能进行了比较,结果表明,FP-Growth关联规则挖掘算法与Apriori相比效率更高,更适合海量数据场景下的告警关联分析。     

基于轻量化关联规则挖掘的安全日志审计技术研究

为了对云计算平台中日志审计数据进行安全分析,提出一种采用改进的关联规则的日志信息挖掘方法,以便有效识别事故类型或者预防可能出现的各种恶意入侵。该方法采用典型的关联规则Apriori算法对比挖掘系统日志和用户行为模式的异常信息,并通过删除稀疏矩阵集合中的弱相关项目集和可调节最小置信度的策略,对Apriori算法进行轻量化改进。在多次迭代运算得到最大项目集后运用于日志审计。仿真实验结果表明,改进的Apriori算法可以有效减少对数据库的扫描次数,提高挖掘效率,具有一定的推广价值。     

大数据量下的Apriori改进算法及在weka平台的实现

文章在分析关联规则和Apriori算法原理的基础上,针对Apriori算法扫描数据库时由于事务数过大,导致系统的I/O负载和CPU运算压力过大等弊端,提出一种主要针对大数据量情况下Apriori算法性能提升的改进算法。主要思想是通过抽样和事务压缩来减少算法需要扫描的事务数,进而提升算法的效率。同时,基于主流的weka开源数据挖掘工具实现了改进算法。实验结果表明了算法的有效性。     

基于布尔矩阵Apriori算法的改进研究

为了高效且快速地从事务数据库中生成频繁项集,在研究基于布尔矩阵Apriori算法的基础上,提出一种改进算法PM Apriori(Prune Matrix Apriori)算法。此算法充分利用矩阵的存储与运算特性,仅扫描数据库一次,不需要生成候选集,有效地提高算法的运算效率,在算法执行过程不断对存储矩阵进行修剪压缩,节省了内存空间和扫描矩阵的时间,并通过算法示例与算法性能对比分析证明所提出的改进算法具有良好的时间特性和空间特性。     

对关联规则挖掘Apriori算法的进一步改进

本文对关联规则挖掘问题进行了介绍。并在分析研究了关联规则挖掘Apriori算法厦其若干改进算法的基础上，对Apriori算法做了进一步地改进，提出了RIAprlori算法。改进后的算法采用事务压缩的方法时事务集进行了更大幅度的压缩。减小了不必要的开销，从而提高了挖掘速度。     

加权频繁项集挖掘算法在超市商品捆绑销售中的应用

引入一种新的加权关联规则支持度和置信度的计算方法,并利用矩阵的存储结构提出一种新的加权关联规则挖掘算法,从而改进了加权频繁项集的挖掘效率.该算法在Apriori算法的基础上,对数据库仅需扫描一次,能很快地计算项集的支持度,大大减少了I/O次数,有效提高了加权频繁项集的生成效率.通过应用于超市捆绑销售,证明了该算法能有效地提取商品间的关联信息,有助于商品的销售.     

一种新型的改进Apriori算法研究

Apriori算法是数据挖掘关联规则研究中的经典算法,由于它需要多次扫描数据库,造成系统运行效率比较低。所以在对Apriori算法进行了分析之后提出了改进的Apriori算法。改进的主要思想是基于将事务数据库转化成相应的0-1矩阵,通过对矩阵中每个向量与其后的向量做内积运算来计算支持度,并将计算得到的支持度与给定的最小支持度作比较,删除小于最小支持度的行与列,缩小矩阵的规模,提高了运行速度效率。改进的算法只需要对数据库扫描一次,运行效率比较高。实验结果表明,该优化方案是有效可行的。     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks