A new carbon structure in annealed film coatings of the carbon–lead system

Carbon–lead solid solutions coexisting with amorphous carbon have been obtained for the first time in a film coating deposited by ion-plasma sputtering. During subsequent vacuum annealing of carbon–lead films containing more than 68.5 at % Pb, this element almost completely evaporates to leave an amorphous carbon coating on a substrate. During annealing at 1100°C, this amorphous carbon crystallizes into a new hexagonal lattice with unit cell parameters a = 0.7603 nm and c = 0.8168 nm. Characteristic X-ray diffraction data for the identification of this phase are determined.

     

Wet etching mechanisms of ITO films in oxalic acid

This study examines how oxalic acid solutions affect indium tin oxide (ITO) etching. Experimental results show that the etching rate of ITO films increased linearly with the concentration of . The open circuit potentials included in the potential-pH diagrams for indium and tin in aqueous oxalic acid systems helped determine that ITO films was dissolved by the formation of in oxalic acid. However, the tin oxide in ITO films was difficult to dissolve, but could be removed by stripping. The EDS analysis and optical microscopic images indicate that the removal rate of SnO₂ in oxalic acid etchants was slower than that of In₂O₃, and many residues were distributed around the ITO bars after the etching process. Moreover, kinetic experiments reveal the high activation energy of ITO etching, and it was found stirring or ultrasonic vibration of the etchants had no influence on the dissolution rate of ITO films at all. Therefore, the rate-determining step should be the chemical reaction on ITO surface. A mechanism including protonation and ligand adsorption was proposed to explain the observed results.     

消除高压噪声的继电器

大多数实验室和工业环境中都存在着多种全频带电气噪声源,它们来自于重型机器、仪表、电源和电视台.工程师要用很多设备和技术来对付这种噪声.这些技术包括采用正确的接地方式、屏蔽和双绞线、信号均化、差分输入电压放大器和滤波器.     

Phase-Noise Reduction of X-Band Push–Push Oscillator With Second-Harmonic Self-Injection Techniques

A low phase-noise X-band push-push oscillator using proposed feedback topology is presented in this paper. The oscillator core was implemented in a 0.18-mum CMOS process. By using a power splitter and a delay path in the feedback loop connecting the output and current source of the oscillator, a part of the oscillator output power injects to the oscillator itself. With the proper phase delay in the feedback loop and high transconductance of the current source, a low phase-noise oscillator is achieved. The amplitude stability and phase stability are analyzed, the phenomena of the phase-noise reductions are derived, and the device-size selections of the oscillator are investigated. The time-variant function, impulse sensitivity function, is also adopted to analyze the phase-noise reductions of the second-harmonic self-injected push-push oscillator. These theories are verified by the experiments. This self-injected push-push oscillator achieves low phase noise of -120.1 dBc/Hz at 1-MHz offset from the 9.6-GHz carrier. The power consumption is 13.8 mW from a 1.0-V supply voltage. The figure-of-merit of the oscillator is -188.3 dBc/Hz. It is also the first attempt to analyze the second-harmonic self-injected push-push oscillator     

Kernel support for zero‐loss Internet service restart

Owing to long serving time and huge numbers of clients, Internet services can easily suffer from transient faults. Although restarting a service can solve this problem, information of the on‐line requests will be lost owing to the service restart, which is unacceptable for many commercial or transaction‐based services. In this paper, we propose an approach to achieve the goal of zero‐loss restart for Internet services. Under this approach, a kernel subsystem is responsible for detecting the transient faults, retaining the I/O channels of the service, and managing the service restart flow. In addition, some straightforward modifications to the service should be made to take advantage of the kernel support. To demonstrate the feasibility of our approach, we implemented the subsystem in the Linux kernel. Moreover, we modified a Web server and a CGI program to take advantage of the kernel support. According to the experimental results, our approach incurs little runtime overhead (i.e. less than 3.2%). When the service crashes, it can be restarted quickly (i.e. within 210 μs) with no information loss. Furthermore, the performance impact due to the service crash is small. These results show that the approach can efficiently achieve the goal of zero‐loss restart for Internet services. Copyright © 2006 John Wiley & Sons, Ltd.     

Using the moving average rule in a dynamic web recommendation system

In this, the Information Age, most people are accustomed to gleaning information from the World Wide Web. To survive and prosper, a Web site has to constantly enliven its content while providing various and extensive information services to attract users. The Web Recommendation System, a personalized information filter, prompts users to visit a Web site and browse at a deeper level. In general, most of the recommendation systems use large browsing logs to identify and predict users' surfing habits. The process of pattern discovery is time-consuming, and the result is static. Such systems do not satisfy the end users' goal-oriented and dynamic demands. Accordingly, a pressing need for an adaptive recommendation system comes into play. This article proposes a novel Web recommendation system framework, based on the Moving Average Rule, which can respond to new navigation trends and dynamically adapts recommendations for users with suitable suggestions through hyperlinks. The framework provides Web site administrators with various methods to generate recommendations. It also responds to new Web trends, including Web pages that have been updated but have not yet been integrated into regular browsing patterns. Ultimately, this research enables Web sites with dynamic intelligence to effectively tailor users' needs. © 2007 Wiley Periodicals, Inc. Int J Int Syst 22: 621–639, 2007.     

Forthcoming Contributions

Table of Contents

Forthcoming Contributions     

Covariance control with observed-state feedback gains for continuous nonlinear systems using T-S fuzzy models

The design problem of state variance constrained control for stochastic systems has received rather extensive attention in recent years. This paper solves the state variance constrained controller design problem by using the covariance control theory, with observed-state feedback gains for continuous Takagi-Sugeno (TS) fuzzy models. By incorporating the technique of state estimation into the practical covariance control theory, a variance constrained control methodology is developed for the continuous TS fuzzy models. Finally, a numerical example is shown to demonstrate the efficiency and applicability of the proposed approach.     

A New Damper Scheme to Restrict Torsional Torques on the Turbine Generator Shafts and Blades near a HVDC Link

Due to more various power disturbances occurring in a power system involving a HVDC link, the turbine generator shafts and/or blades are more prone to damage than in general HVAC systems. In this paper, a new mechanical damper scheme based on participation factor approach is proposed to damp torsional torque and prolong the life of turbine mechanism. Two types of torsional damping couplings, inertia damping coupling and elastic damping coupling, are adopted and examined. The optimal type and the optimal location of the damping coupling will be identified and installed to the turbine generator shaft section. The results demonstrate that the best damper may not be installed at the location with the most onerous vibrations but provides satisfactory damping performance on shafts and blades following severe power disturbances in a HVDC link.