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Title: ACES Journal May 2017 Cover
File Type: Journal Paper
Issue:Volume: 32      Number: 5      Year: 2017
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Title: ACES Journal May 2017 Front/Back Matter
File Type: Journal Paper
Issue:Volume: 32      Number: 5      Year: 2017
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Title: ACES Journal May 2017 Full
File Type: Journal Paper
Issue:Volume: 32      Number: 5      Year: 2017
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Title: Symbolic Regression for Derivation of an Accurate Analytical Formulation Using “Big Data”: An Application Example
Abstract: With emerging of the Big Data era, sample datasets are becoming increasingly large. One of the recently proposed algorithms for Big Data applications is Symbolic Regression (SR). SR is a type of regression analysis that performs a search within mathematical expression domain to generate an analytical expression that fits large size dataset. SR is capable of finding intrinsic relationships within the dataset to obtain an accurate model. Herein, for the first time in literature, SR is applied to derivate a full-wave simulation based analytical expression for the characteristic impedance Z0 of microstrip lines using Big Data obtained from an 3DEM simulator, in terms of only its real parameters which are substrate dielectric constant ?, height h and strip width w within 1-10 GHz band. The obtained expression is compared with the targeted simulation data together with the other analytical counterpart expressions of Z0 for different types of error function. It can be concluded that SR is a suitable algorithm for obtaining accurate analytical expressions where the size of the available data is large and the interrelations within the data are highly complex, to be used in Electromagnetic analysis and designs.
Author(s): P. Mahouti, F. Günes, M. A. Belen, S. Demirel
File Type: Journal Paper
Issue:Volume: 32      Number: 5      Year: 2017
Download Link:Click here to download PDF     File Size: 2007 KB

Title: Artificial Intelligence Technology and Engineering Applications
Abstract: There has been sixty-year development of the artificial intelligence (AI) and the maturation of AI techniques is now leading to extensive applications and industrialization. In this paper, authors review the connotation and evolution of AI techniques and engineering applications. A four-layer framework of the AI technology system is summarized in this paper to help readers understand AI family. Engineering applications of AI techniques have made remarkable progress in the recent years, for instance, applications in fault diagnosis, medical engineering, petroleum industry and aerospace industry. By introducing the state-of-the-art of AI technologies, it can help the researchers in both engineering and science fields get ideas on how to apply AI techniques to solve application-related problems in their own research areas.
Author(s): X. Li, H. Jiang
File Type: Journal Paper
Issue:Volume: 32      Number: 5      Year: 2017
Download Link:Click here to download PDF     File Size: 1659 KB

Title: Enhanced Energy Localization with Wideband Hyperthermia Treatment System
Abstract: This paper presents a tool to enhance hyperthermia treatment based on multichannel wideband system. The potential of this system in enhancing energy localization is investigated. A model is developed for the hyperthermia treatment plan taking into account cylindrical phantom of human head. Dispersive modeling of tissue properties is used to allow wideband simulation. Problem formulation for optimization of wideband system is presented. Simplified time-delay tool based on coherent phased-array approach is developed and presented. The results reveal the potential of wideband system compared to conventional narrow band systems in enhancement of energy focus. Investigation of advanced optimization processes is introduced that allow real time shaping of the signal waveform in wideband systems. The research addresses the importance of incorporating recent techniques in processing big data to facilitate adopting wideband hyperthermia in clinical systems.
Author(s): N. Nizam-Uddin, I. Elshafiey
File Type: Journal Paper
Issue:Volume: 32      Number: 5      Year: 2017
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Title: Design of Tilted-Beam Fabry-Perot Antenna with Aperiodic Partially Reflective Surface
Abstract: A fast synthesis model for designing highgain tilted-beam antennas with the aperiodic partially reflective surface (PRS) is presented in this paper. In this model, concepts of array synthesis and thinning are introduced to realize the tilted beam and control the sidelobe level (SLL). Since a large number of data need to be processed during the optimization process, an efficient hybrid real-binary bat algorithm (HRBBA) is proposed and embedded in the model to optimize the loop widths and the absence of the square loops on the PRS. As an example, an antenna with an expected tilted beam in the elevation plane (? = 40°) is manufactured and measured, and both the simulated and measured results show that the antenna can tilt its beam toward the expected direction with good performance.
Author(s): Y.-F. Cheng, W. Shao, X. Ding, M.-X. Yu
File Type: Journal Paper
Issue:Volume: 32      Number: 5      Year: 2017
Download Link:Click here to download PDF     File Size: 1779 KB

Title: Distributed Markov Chain Monte Carlo Method on Big-Data Platform for Large-Scale Geosteering Inversion Using Directional Electromagnetic Well Logging Measurements
Abstract: Inversion problems arises in many fields of science focusing on the process that explores the causal factors from which a set of measurements are observed. Statistical inversion is an alternative approach compared to deterministic methods with better capability to find optimal inverse values. Due to the increasing volume of data collections in the oil and gas industry, statistical approaches show its advantage on the implementation of large-scale inverse problems. In this paper, we address on the solution of big-data-scale inverse problems. After examining both conventional deterministic and statistical methods, we propose a statistical approach based on the Markov Chain Monte Carlo (MCMC) method and its implementation with the scalable dataset on the big data platform. The feasibility and methods to apply statistical inversion on the big data platform is evaluated by examining the use of parallelization and MapReduce technique. Numerical evidence from the simulation on our synthetic dataset suggests a significant improvement on the performance of inversion work.
Author(s): Q. Shen, X. Wu, J. Chen, Z. Han
File Type: Journal Paper
Issue:Volume: 32      Number: 5      Year: 2017
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Title: A Double Band-Notched UWB Antenna for Flexible RF Electronics
Abstract: A double band-notched UWB compact antenna based on ultrathin liquid crystal polymer (LCP) substrate is designed and experimented for flexible electronics in this paper. The antenna is constituted by swallow tail radiation patch and trapezoid ground. Two elliptic single complementary split-ring resonators (ESCSRRs) are used to realize double band-notched characteristic in UWB band. The measurement results show that the VSWRs of antennas are lower than 2 in the whole UWB band (3.1 GHz-10.6 GHz) except the two band-notched frequency-bands in 3.7 GHz-4.2 GHz and 5.15 GHz-5.825 GHz. The bending performance of band-notched UWB antenna are measured. The measured radiation patterns indicate that the antenna is an omni-directional antenna both at flat and bent circumstances. The overall dimension of the antenna is 27 mm × 21 mm × 0.05 mm. These results suggest that this compact mechanical flexible antenna would be useful for flexible UWB wireless system.
Author(s): C. Rong, W. Xiao, Y. Xu, M. Xia
File Type: Journal Paper
Issue:Volume: 32      Number: 5      Year: 2017
Download Link:Click here to download PDF     File Size: 2101 KB

Title: Fast Prediction of Coupling Coefficient between Monopole Antennas on Electrically Large Cylindrical Platforms Using a Linear Parametric Model
Abstract: Antenna placement on electrically large cylindrical platforms requires a number of time consuming computer simulations that involve analysis of big electromagnetic data. In order to save simulation time, a linear parametric model is proposed to predict the coupling coefficient between monopole antennas on electrically large cylindrical platforms. The two parameters of the model are determined by the values of coupling coefficients at two different distances. The parametric model is then used to predict the coupling coefficient between monopole antennas at various distances. The proposed parametric model avoids repeated time consuming analysis of big electromagnetic data for predicting the coupling coefficients at various distances, and it thus significantly reduces simulation time. Given the desired level of isolation, the proposed parametric model can be used to find the required distance without a trial-and-error process, which further saves the time required by the analysis of big electromagnetic data.
Author(s): H. Zhao, S.-P. Gao, W.-J. Zhao, Y. Zhang, J. Hu, Z. Chen
File Type: Journal Paper
Issue:Volume: 32      Number: 5      Year: 2017
Download Link:Click here to download PDF     File Size: 1618 KB

Title: A Compact Triple Band Antenna for Bluetooth, WLAN and WiMAX Applications
Abstract: In this paper, we propose a compact triple band microstrip antenna, whose performance is discussed and investigated by using full-wave simulation and measurements. To achieve expected triple-band characteristics, three nested loop radiation elements are presented and a rectangular stub connected to the feed line is also introduced. Our proposed antenna has a size of 28 mm×41 mm and a thickness of 1.5 mm, which is fed by a coplanar waveguide (CPW). The simulated and measured results show that the proposed antenna provides a tri-band characteristic that covers 2.1-2.8 GHz, 3.3-4.0 GHz and 5.5-5.8 GHz. The center frequencies of the designed triple bands can be controlled by adjusting the dimensions of the nested loop elements. As a result, the designed tri-band antenna has a good impedance matching characteristic and omnidirectional radiation patterns, which make the proposed antenna could be a favorable candidate for Bluetooth, WiMAX and WLAN applications.
Author(s): K. Yu, Y. Li, W. Yu
File Type: Journal Paper
Issue:Volume: 32      Number: 5      Year: 2017
Download Link:Click here to download PDF     File Size: 1950 KB

Title: Multiplication Theory for Prediction of the Scattering Grating-lobe of Array Antenna
Abstract: Experimental results reported in many literature have demonstrated that an antenna array should have two or more grating lobes in its scattering pattern; however, it is not clear how these grating lobes occur and vary. In this paper, we propose a new method to predict the number and location of scattering grating lobes generated by an array antenna. In the proposed method, the radar cross section (RCS) of array antenna can be decomposed into multiplication of the array RCS factor and the element RCS factor. The array RCS factor bears universal applicability so that it can be used to directly determine scattering properties of array antenna. Compared with the full-wave simulation techniques, the new method requires much less computation time and memory storage so that it is more suitable to be employed as the basis of a synthesis method to predict the desired RCS pattern of a large array antenna. As examples, the scattering properties of the dipole antenna arrays are investigated to validate the new method, numerical results demonstrate that the number and location of scattering grating lobes predicted by using the proposed method coincide with those simulated by using a MoM based commercial; software FEKO.
Author(s): S. Zhang, X. Wang, L. Guo, J. Ma
File Type: Journal Paper
Issue:Volume: 32      Number: 5      Year: 2017
Download Link:Click here to download PDF     File Size: 1862 KB

Title: Compact UWB Microstrip-fed Slot Antenna with Dual-band Rejection by Using EBG and Four-arm Spiral Structures
Abstract: A microstrip-fed slot antenna with dual rejection bands is designed and prototyped for ultrawideband (UWB) applications. The rejection band for WiMAX is achieved by symmetrical etching a pair of nested four-arm spiral slots on the ground plane. Selfinterdigital electromagnetic band-gap (EBG) structures are embedded to create other rejection bands for WLAN and are placed on both sides of the gradient T-shaped microstrip-fed. The simulated result and measurement data show that the antenna impedance bandwidth (Voltage Standing Wave Ratio is less than 2) covers the entire UWB bandwidth range with two eliminated bands of 3.22-3.81 GHz (0.59 GHz, 16.7%) and 5.11- 5.84 GHz (0.73 GHz, 13.4%). In addition, the designed antenna achieves a stable gain and exhibits omnidirectional radiation patterns except at rejection frequency bands, which makes it a suitable candidate for UWB applications that will not be interfered by WiMAX/WLAN systems.
Author(s): J. Ma, S. Zhang, Q.-J. Li, J. Du
File Type: Journal Paper
Issue:Volume: 32      Number: 5      Year: 2017
Download Link:Click here to download PDF     File Size: 1581 KB

Title: A Low Complexity High Performance Robust Adaptive Beamforming
Abstract: In this paper, we propose a low complexity adaptive beamforming with joint robustness against array steering vector (ASV) mismatch and array manifold errors. The proposed robust beamforming is based on the diagonal loading technique, and the diagonal loading factor can be adjusted adaptively according to the input signal-to-noise ratios (SNRs). The eigenvalue corresponding to the desired signal is identified by projecting the presumed ASV of the desired signal onto the eigenvectors of the sample covariance matrix. We find that the ratio of the eigenvalues corresponding to the desired signal and the noise can be used to accurately reflect the input SNR when the input SNRs is large enough, and the ratio is also the diagonal loading factor. Then, an orthogonal subspace is obtained with the steering vectors associated with the region where the desired signal may locate at. Also, the actual steering vector is estimated as a linear combination of this orthogonal subspace. In order to further reduce the computation complexity, we use the traditional diagonal loading method in low SNRs. Simulations results demonstrate that the proposed beamformer provides strong robustness against a variety of array mismatches, and the complexity is significantly reduced compared with popular existing methods.
Author(s): W. Li, X. Mao, Z. Zhai, Y. Li
File Type: Journal Paper
Issue:Volume: 32      Number: 5      Year: 2017
Download Link:Click here to download PDF     File Size: 1724 KB

Title: Optical Cloak Design Exploiting Efficient Anisotropic Adjoint Sensitivity Analysis
Abstract: We propose in this work a novel optimizationbased wideband invisibility cloaking approach at optical frequencies. We exploit the memory efficient anisotropic adjoint variable method (AVM) to significantly accelerate the sensitivity analysis with respect to the large number of parameters. Minimizing the cloaking objective function involves the gradients estimation with respect to a massive number of parameters at every iteration for time-intensive electromagnetic simulations. The AVM evaluates the required gradients over one thousand time faster than conventional methods. The significant reduction in the computational cost enables wideband optimization-based cloak design at optical region.
Author(s): L. S. Kalantari, M. H. Bakr
File Type: Journal Paper
Issue:Volume: 32      Number: 5      Year: 2017
Download Link:Click here to download PDF     File Size: 2096 KB

Title: Analysis and Design of Class E Power Amplifier with Finite DC-Feed Inductance and Series Inductance Network
Abstract: With the increasing operation frequency, it is essential to take into account the parasitic parameters of transistor for high efficiency microwave power amplifier design. In this paper, a class E power amplifier with finite dc-feed inductance and series inductance network is analyzed including the parasitic inductance of transistor. The analytical design expressions are derived. And the effects of series inductance on the load network parameter are obtained. The results suggest that this new topology can be used in broadband power amplifiers design by making full use of transistor’s output parasitic inductance. A GaN HEMT power amplifier is designed with the proposed topology for validation purpose. Experimental results show that the amplifier can realize from 2.5 GHz to 3.5 GHz (33.3%) with measured drain efficiency larger than 60% and output power larger than 34 dBm. The measured performance shows good agreement with the theoretical performance predicted by the equations.
Author(s): C. Rong, X. Liu, Y. Xu, R. Xu, M. Xia
File Type: Journal Paper
Issue:Volume: 32      Number: 5      Year: 2017
Download Link:Click here to download PDF     File Size: 1993 KB