ALBERT

Description: Behavior of different planar multilayer periodic structures due to plane wave excitation has been studied using the transfer matrix method. Multilayer structure is composed of odd number of slabs and the layers at odd locations have same characteristics and layers at even locations have same characteristics. For each structure, layers at odd locations are of chiral nihility metamaterial whereas three different cases are considered for layers at even locations, i.e., dielectric, chiral and chiral nihility. Effects of polarization rotation due to the optical activity of material's chirality is studied with respect angle of incidence and frequency in THz region. Chiral nihility adds property of transparency to the structure for normal incidence. Chiral nihility-chiral nihility structure for normal incidence yields transparency whereas same structure for oblique incidence yields total rejection at higher frequencies. Content Type Journal Article Pages - DOI 10.3233/JAE-131724 Authors Nayyar Abbas Shah, Department of Electronics, Quaid-i-Azam University, Islamabad, Pakistan Faiz Ahmad, Department of Physics, COMSATS Institute of Information Technology, Islamabad, Pakistan Aqeel A. Syed, Department of Electronics, Quaid-i-Azam University, Islamabad, Pakistan Qaisar A. Naqvi, Department of Electronics, Quaid-i-Azam University, Islamabad, Pakistan Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: The contact behavior between a transversely isotropic piezoelectric material and a rigid-conducting punch of flat-end was analyzed under the condition that there is no biased-electric potential applied to the punch. Two limiting cases were studied; one was for semi-infinite piezoelectric materials and the other for piezoelectric films with contact radius much larger than the film thickness. Analytical relationships were derived between the indentation load and the indentation depth and between the indentation-induced potential and the indentation depth. Both the indentation load and the indentation-induced potential are proportional to the indentation depth. For the adhesive contact, the pull-off force is proportional to the 3/2 power of the punch radius for semi-infinite piezoelectric materials and to the square of the punch radius for piezoelectric films. The piezoelectric charge coefficient determined from the contact deformation of a piezoelectric film with contact radius much larger than the film thickness is only dependent on dielectric constant and piezoelectric constant. Content Type Journal Article Pages - DOI 10.3233/JAE-131721 Authors Fuqian Yang, Materials Program, Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506, USA. Tel.: +1 859 257 2994; Fax: +1 859 323 1929; E-mail: fyang0@engr.uky.edu Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: This paper deals with the novel structure and coupling analysis of a 3-degrees of freedom (3-DOF) conical magnetic bearing. The conical stators of the bearing are designed symmetrical to provide the axial control exclusively, and the radial stators are separated by nonmagnetic material between X and Y channels, so the magnetic flux path can be separated among different channels. The configuration and working principle of the bearing are provided, and the mathematical model is derived based on the bias and control magnetic circuits. In order to evaluate the degree of force coupling between different channels, the concept of coupling factor is proposed, which is defined as the ratio of force variation caused by coupling to the original force when there is no coupling. The coupling factors are analyzed not only among the translational movement of X, Y and Z channels but also between the translational and rotational degrees of freedom. The calculation results show that although the component coupling factors of each magnetic poles are a little larger, the resultant ones in X, Y and Z directions of the designed bearing are all less than 4%. Therefore, the magnetic forces and torques of different channels are weakly coupled, and it is convenient for the control of the magnetic bearing. Content Type Journal Article Pages - DOI 10.3233/JAE-131725 Authors Chun'e Wang, Science and Technology on Inertial Laboratory, Fundamental Science on Novel Inertial Instrument and Navigation System Technology Laboratory, Beihang University, Beijing, China Jiancheng Fang, Science and Technology on Inertial Laboratory, Fundamental Science on Novel Inertial Instrument and Navigation System Technology Laboratory, Beihang University, Beijing, China Jiqiang Tang, Science and Technology on Inertial Laboratory, Fundamental Science on Novel Inertial Instrument and Navigation System Technology Laboratory, Beihang University, Beijing, China Jinji Sun, Science and Technology on Inertial Laboratory, Fundamental Science on Novel Inertial Instrument and Navigation System Technology Laboratory, Beihang University, Beijing, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: In order to improve recycling quality of asphalt mixtures based on microwave heating, thermoelectric coupling theory is researched. Heat conduction equation is built according to Fourier's Law. Series model, parallel model and Maxwell model are studied to solve thermal conductivity of asphalt mixtures. Radiation field model of pyramidal horn antenna is set up and mean value of electric field intensity is measured by experiment. Thermoelectric coupling model is built on the basis of dielectric property of asphalt mixtures. Numerical simulation is performed for the model. It is found that influence of asphalt-aggregate ratio on temperature field is not distinct. Average temperature of asphalt mixtures is related to microwave power and increases with microwave power linearly. The asphalt mixtures using diorite as aggregate have a strongest adsorption capability to energy. The result can simulate hot in-place regeneration process, and has important significance to improve regeneration quality of asphalt mixtures. Content Type Journal Article Pages - DOI 10.3233/JAE-131722 Authors Tongsheng Sun, School of Mechanical and Automotive Engineering, Anhui Polytechnic University, Wuhu 241000, Anhui, China. Tel.: +86 553 287 1252; E-mail: suntongsheng@ahpu.edu.cn Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Mobile broadband services have expanded considerably in recent years, driving operators to improve and densify their radio access network (RAN). It has become clear that small cells as well as macrocells must be included in a heterogeneous network, due to the scale of densification required. In order to maximize the end user experience, some level of radio coordination between these small and macrocells is needed ?? this coordination will be signaled across a mobile backhaul network. Mobile backhaul typically refers to the network between the base station site and the network controller site, but can also include interconnection between base station sites. Mobile backhaul includes a spectrum of networks and network technologies, including the RAN and core networks. There is considerable market interest on the development of small cell backhaul solutions that are an evolution of existing backhaul networks. Packet synchronisation mechanisms that are being developed are key to support the mobile backhaul application. Various standards bodies such as the Next Generation Mobile Networks Alliance (NGMN), Small Cell Forum (SCF), Metro Ethernet Forum (MEF), and Broadband Forum (BBF) are also studying what the implications would be on their defined mobile backhaul network architectures.

Description: Heterodyne generation of parallel random bit streams from chaotic emission of an optically injected semiconductor laser is investigated. The continuous-wave optical injection invokes chaotic dynamics in the laser. The broadband chaotic emission is detected through optical heterodyning and electrical heterodyning into different channels. The channels digitize the signals into parallel independent random bit streams. Because of efficient utilization of different portions of the chaos bandwidth, heterodyne detections enable parallel generation of random bit streams, offer high total output bit rates, and require no high-bandwidth analogue-to-digital converters. In the experiment, two optical heterodyne channels and four electrical heterodyne channels are implemented. Each channel is required to digitize only 2.5 GHz of a much broader chaos bandwidth. The sampling rate is 10 GHz with five least significant bits selected from every 8-bit sample. The total output bit rate reaches 100 Gb/s and 200 Gb/s for optical and electrical heterodyning, respectively. The standard test suite of the National Institute of Standards and Technology verifies the randomness of both individual and interleaved output bit streams.

Description: In this article, we introduce the EstiNet OpenFlow network simulator and emulator, and present its support for testing the functions and evaluating the performances of software-defined networks?? OpenFlow controller??s application programs. EstiNet uses an unique kernel reentering simulation methodology to enable unmodified real applications to run on nodes in its simulated network. As a result, without any modification, real NOX/POX or Floodlight OpenFlow controllers can readily run on a host in an EstiNet simulated network to control thousands of simulated OpenFlow switches. EstiNet has the characteristics of a simulator and an emulator at the same time. It combines the advantages of the simulation and emulation approaches without their respective shortcomings. EstiNet uses real OpenFlow controller programs, real network application programs, and the real TCP/IP protocol stack in the Linux kernel to generate correct, accurate, and repeatable SDN application performance results. In this article, we compare EstiNet with ns-3 and Mininet regarding their capabilities, performance, and scalability.

Description: This article discusses novel wireless and optical technologies to address the radical new challenges of small cell mobile backhaul (MBH). Specifically, we examine 60 GHz and 70??80 GHz millimeter-wave technologies for high-capacity last mile and pre-aggregation backhaul, and orthogonal frequency-division multiple access passive optical networks as the optical technology complement for enabling flexible cost-efficient hybrid backhaul coverage. Flexible high-capacity hybrid millimeter wave/optical MBH network operation is next verified via network simulations in the context of a demanding, urban small-cell backhaul application. Finally, a novel software defined networking tool called the backhaul resource manager is introduced for automated dynamic resource provisioning and capacity-aware path computation that improves fairness, network utilization and end-to-end user quality of experience. The introduction of the novel wireless, optical, and software-defined technologies thus has the potential to truly revolutionize the future MBH network.

Description: In this article we discuss different technology alternatives for small cell backhaul, and we present high-frequency microwave technology as a very interesting alternative for wireless backhauling of small cells. In fact, we demonstrate that high-frequency microwave technology can be used for NLOS wireless backhauling of small cells, which opens up new applications for microwave technology. We discuss urban NLOS channel propagation at high frequencies, and we show both measurement and simulation results to validate the use of high-frequency microwave technology for NLOS small cell backhaul.

Description: A novel design and assembly technology is developed for a three-dimensional (3-D) flexible thermal flow sensor based on convective heat transfer to reduce detection error caused by position variation of a sensor inside the flow of narrow and curved geometries, such as coronary artery. The 3-D sensor has three independent sensing elements equally distributed around the catheter tube. This arrangement introduces three independent information channels, and cross-comparisons are used to provide accurate flow measurement. The resistance of the sensing elements is measured at ${sim}{1}-1.2~{rm k}Omega$ with the temperature coefficient of resistance at $0.086%/^{circ}{rm C}$ . Using a constant-current circuit, the three sensing elements are heated to ${sim}10^{circ}{rm C}$ above ambient temperature. Flow testing is implemented in a pipe channel at two positions: on the wall and along the center line. Experimental results from these two positions are discussed and computational fluid dynamic simulation based on Newtonian fluid properties is implemented, showing comparable results within an acceptable range of experimental to simulation errors. Therefore, we demonstrate the capability of 3-D thermal flow sensor for detecting the position of the catheter in the flow channel, thereby providing an accurate flow measurement.