解决Web服务信誉度评估中恶意反馈问题研究

本文提出了一种针对恶意反馈的信誉度评估的方法,该方法的主要思想是通过绑定主机MAC地址与Web服务,限制同一MAC地址频繁反馈、伪造MAC地址等恶意行为,提高了Web服务选择中信誉度评估结果的准确性。     

Web服务中信誉度评价模型研究

网络中Web服务的日益增加使得服务安全和服务选择变得日益重要,而Web服务的信誉度作为服务安全和服务选择的基础成为了当下研究的热点。对Web服务信誉评价的性质和概念进行阐述以及信誉度在Web服务选择中的重要性进行了论证。同时,对现有的Web服务信誉评价模型进行了研究和分析,详细描述了各Web服务信誉度评价模型的信誉来源、建模原理以及建模过程,并且对比了各模型的优势以及不足,为后续研究方向提供了参考依据。     

基于OWL-S的Web服务质量本体的描述模式的设计

基于WSDL的Web服务描述没有涉及到Web服务语义信息的表示,仅仅从语法的角度解决了Web服务信息的描述。随着语义Web概念的提出,如何描述Web服务的语义信息成为学术界研究的热点。论述了OWL S语言如何实现对Web服务的语义描述。同时针对OWL S在描述服务质量方面的不足,提出了Web服务质量本体的描述模式,以方便根据Web服务的质量信息对服务类中的服务进行筛选。     

基于语义Web服务的发布/订阅模型研究

基于面向服务架构,引入发布/订阅通信方式,提出了基于语义Web服务的发布/订阅模型,可以满足时间解耦、空间解耦和同步解耦的需求.模型通过基于OWL-S的服务描述解决了服务的语义问题.具体探讨了在语义Web服务的发布/订阅模型下,Web服务语义描述模型、语义Web服务匹配模型和语义Web服务匹配流程的设计策略和方法.     

一种基于QoS的语义Web服务本体模型

语义Web服务是结合语义Web和Web服务两方面技术的一门新的研究课题.文中利用语义网的本体技术,在综合考虑为用户选择提供最佳服务和添加语义描述的基础上,分析设计了一种基于Oos的语义Web服务本体模型,并针对票务服务领域进行了实例设计和语义描述.     

基于本体的语义Web服务注册平台研究

提出了一种基于本体的语义Web服务注册模型,结合Jena实现语义Web服务的语义查询和推理.应用元模型互操作框架(MFI)中的本体注册元模型标准,以实现与其他注册模型的语义互操作,并给出了一个基于该模型的语义Web服务注册平台.     

基于语义Web服务的智能电信业务模型

该文针对电信业务领域用户需求多样化的实际情况,将互联网领域语义Web服务模型进行完善,提出了基于语义Web服务的智能电信业务模型。在模型中,设计了电信业务领域本体库,实现了电信业务领域知识的共享;提出了基于本体的用户个性数据库,利用本体的天然推理特性加强对用户个性的挖掘;引入了智能代理,将用户从浩淼的服务选择中解放出来。设计了语义转换XSLT代码生成模块提高了语义Web服务描述效率。该模型已经在实际的测试环境中得到验证,最后以流媒体业务为例,说明了该模型的工作原理。     

基于核Batch SOM聚类优化的语义Web服务发现机制研究

如何快速、准确和高效地发现满足用户需求的Web服务已成为制约服务发展的瓶颈之一。该文针对现有Web服务发现机制中存在的效率低下和查准率不高的两个主要问题,提出了一个基于核Batch SOM神经网络聚类优化的语义Web服务发现框架。该框架分别在服务表示阶段引入WordNet和隐含语义索引技术对Web服务进行语义扩展和概念语义空间降维;在服务分类阶段利用核机学习理论改进一类适用于Web服务分类的核Batch SOM神经网络算法;在服务匹配阶段提出一种基于核余弦相似性测度的Web服务匹配算法。最后,真实Web服务数据集上的实验结果验证了所提出方法的可行性。     

基于Chord的语义Web服务发现与合成的研究

提出一种基于Chord的语义Web服务发现与合成模型.将注册中心注册到分布式Chord网络中并基干领域本体对注册中心分类,使用本体描述为Web服务加入语义信息,语义Web弥补了传统Web语义不足的缺点.实验分析表明,该模型系统能提高Web服务发布、发现及合成的效率和准确率.     

基于P2P的语义Web服务发现模型研究

为解决现有的Web服务缺少形式语义支撑,文中提出了一种基于P2P的语义Web服务发现模型,在P2P发现方面加入了本体信息,引入一种新的本体编码方式,使得Web服务在P2P层内支持语义发现,提高了Web服务发现的准确性和即时性.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.     

GaAsSb/InAlAs PA DHBTs Grown by Production MBE

The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4 × 100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor. The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb. A Sb composition variation of less than ± 0.1 atomic percent across a 4 × 100mm platen configuration has been achieved. The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BVCEO＞6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm × 50μm. The devices have a 40nm thick GaAsSb base with p-doping of 4. 5 × 1019cm-3 . Devices with an emitter size of 4μm × 30μm have a current gain variation less than 2% across the fully processed 100mm wafer. ft and fmax are over 50GHz,with a power efficiency of 50% ,which are comparable to standard power GaAs HBT results. These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.     

Noise character analysis and the restraint of self-pulsation laser diodes

We calculate the Langevin noise sources of self-pulsation laser diodes, analyze the effects of active region noise and saturable-absorption region noise on the power fluctuation as well as period fluctuation, and propose a novel method to restrain the noise effects. A visible SIMULINK model is established to simulate the system, The results indicate that the effects of noise in absorption region can be ignored; that with the increase of DC injecting current, the noise effects enhance power jitter, and nevertheless, the period jitter is decreased; and that with external sinusoidal current modulating the self-pulsation laser diode, the noise-induced power jitter and period jitter can be suppressed greatly. This work is valuable for clock recovery in all-optical network.     

High-quality single-crystal CdSe nanoribbons and their optical properties

Large-scale synthesis of single-crystal CdSe nanoribbons is achieved by a modified thermal evaporation method, in which two-step-thermal-evaporation is used to control CdSe sources＇ evaporation. The synthesized CdSe nanoribbons are usually several micrometers in width, 50 nm in thickness, and tens to several hundred micrometers in length. Studies have shown that high-quality CdSe nanoribbons with regular shapes can be obtained by this method. Room-temperature photolumines-cence indicates that the lasing emission at 710 nm has been observed under optical pumping （266 nm） at power densities of 25-153 kW/cm^2. The full width half maximum （FWHM） of the lasing mode is 0.67 nm     

Propagation of hermite-cosh-gaussian beams passing through ABCD optical system with an annular aperture

By using the expansion of the aperture function into a finte sum of complex Gaussian functions, the corresponding analytical expressions of Hermite-cosh-Gaussian beams passing through annular apertured paraxially and symmetrically optical systems written in terms of ABCD matrix were derived, and they could reduce to the cases with squared aperture. In a similar way, the corresponding analytical expressions of cosh-Gaussian beams through annular apertured ABCD matrix were also given. The method could save more calculation time than that by using the diffraction integral formula directly.     

Influence of polarization extinction ratio on distributed polarization coupling detection

Distributed polarization coupling in polarization-maintaining fibers can be detected by using a white light Michelson interferometer. This technique usually requires that only one polarization mode is excited. However, in practical measurement, the injection polarization direction could not be exactly aligned to one of the principal axes of the PMF, so the influence of the polarization extinction ratio should be considered. Based on the polarization coupling theory, the influence of the incident polarization extinction on the measurement result is evaluated and analyzed, and a method for distributed polarization coupling detection is developed when both two orthogonal eigenmodes are excited.     

Call for Papers

正Communications—VLSI Researches and industries of telecommunications have been growing rapidly in the last 20 years and will keep their high growing pace in the next decade.The involved researches and developments cover mobile communications,highway and last-mile broadband communication,domain specific communications,and emerging D2D M2M communications.Radio communication steps into its