Advanced Materials Research Vol. 705

Abstract: In this paper a simple method is used for fabrication of vertically aligned carbon nanotube (VACNT) within the cylindrical pores anodic aluminum oxide (AAO) substrate. Electronic and mechanical properties of VACNT have been obtained after removing AAO substrate. Vertically aligned carbon nanotube shows very interesting electromechanical properties which can be used in CNT-based sensors to detect chemical analytical or physical properties such as temperature orpressure.

Abstract: Conservation of the energy available in each sensor node and increasing network lifetime are most important design issues for a wireless sensor network (WSN). Many routing algorithms have been developed in this regard. Out of all these, clustering algorithms have gained a lot of importance in increasing the network lifetime thereby the efficiency of the nodes in it. Clustering provides an effective way for prolonging the lifetime of WSN. This paper elaborately compares the two renowned routing protocols namely, LEACH and EAMMH supported by simulations scenarios, and analysis of the results against known metrics with energy and network lifetime being major among them.

Abstract: This study concerns the development of an embedded system with low computational resources and low power consumption. It uses the NXP LPC2106 with ARM7 processor architecture, for acquiring, processing and classifying images. This embedded system is design to detect and recognize traffic signs. Taking into account the processor capabilities and the desired features for the embedded system, a set of algorithms was developed that require low computational resources and memory. These features were accomplished using a modified Freeman Method in conjunction with a new algorithm "ear pull" proposed in this work. Each of these algorithms was tested with static images, using code developed for MATLAB and for the CMUcam3. The road environment was simulated and experimental tests were performed to measure traffic signs recognition rate on real environment. The technical limitations imposed by the embedded system led to an increased complexity of the project, however the final results provide a recognition rate of 77% on road tests. Thus, the embedded system features overcome the initial expectations and highlight the potentialities of both algorithms that were developed.

Abstract: This paper introduces an application of wireless sensor network based on the ZigBee -- the Smart-Scene system. In-depth analysis of factors of invalid power consumption, a functional separated sink node is designed and a DPM (Dynamic Power Management) schema of dynamic node based on event-driven is proposed. The schema is used in Smart-Scene system and the experimental results indicate it is high feasibility and reduce energy consumption. This method will become an effective solution for wireless sensor network.

Abstract: Ultra-small Chip Power Inductors play an important role in the new TFT-LCD, OLED and other display equipment and other high-end electronic equipment, there are many problems in the traditional power inductors,design and manufacture the small inductor has a very important significance, from small-scale processing, positioning assembly processing, and combine surface and the point welding processing, a whole forming handle, bulk welding and bulk dispensing processing six aspects in designing and manufacturing, practice has proved that take this design, suitable for mass production, can greatly improve the productive efficiency.

Abstract: An important parameter in MEMS design is the electrical contact resistance. This depends on material conductibility, on the geometry of the contacting surfaces, on the applied load and on the current passing through the contact. This work aims to experimentally investigate the dependence between: electrical contact resistance and contact load force, contact resistance and contact area and contact perimeter for constant current through a microcontact.

Abstract: According to the approach presented in this paper, the disturbing force of dynamic mechanical systems can be estimated using Kalman Filter techniques. It has been shown how multiple sensors can be included to improve the estimation accuracy and how the algorithm responds to changing parameters and model inaccuracies. Finally, the approach has been experimentally verified with a MEMS-sensor and a more complex dynamic structure of a milling machine with active magnetic guides. Future enhancements may especially regard the model side, since the estimation accuracy is directly determined by the model quality.

Abstract: The installation of Fault Current Limiter (FCL) brings many advantages to power systems. Therefore, in recent years, many kinds of FCL have been developed. This paper describes a new type of FCL, it’s composed by a tandem resistance and a self rectified voltage source inverter, connected to the distribution line by a coupling transformer. It realizes the limiting by controlling the reactive power. Its prominent features are: simple configuration, lower voltage level. This paper aims to evaluate the operating characteristics of such FCL in both simulation and experimental research ways.

Abstract: Manipulator dynamics is investigated on the basis of closed kinematic chain, in comparison to manipulator on the base of non-closed kinematic chain. Thereby the dynamic peculiarities of their driving actuators are considered. The solution of the task of program motion development was received as a solution of inverse task of kinematics. The modeling issues of investigated manipulators dynamics are resolved and the results were attained. The attained results demonstrate that the application of flat closed mechanisms as the operating device of manipulation robots is promising from the perspective of enhancement of their dynamical peculiarities.

Abstract: The problem of entropy generation due to heat transfer in an electro-osmotic flow with circular type area section micro-channels for small values of electro-kinetic parameter κα (where κ is the Debye length and a is the radius of the micro-channel) is investigated analytically. The momentum and energy conservation equations in cylindrical coordinates for an electro-osmotic flow are derived in non-dimensional form. The momentum equation is solved and velocity distribution in terms of modified Bessel function of the first kind is obtained. An approximation is used for the Bessel function of first kind. Considering the approximate velocity profile, the energy equation including viscous dissipation effects is solved to obtain the temperature distribution in terms of parametric values of the electro-kinetic parameter and the Brinkman number. A uniform surface heat flux boundary condition is considered. The importance of this investigation is development of an engineering simple method of design for electro-osmotic circular micro-electronic cooling systems and possible optimizations of these kinds of flows with respect to the second-law of thermodynamics through the micro-coolers.