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Fast document summarization using locality sensitive hashing and memory access efficient node ranking

10.11591/ijece.v6i3.pp945-954
Ercan Canhasi
Text modeling and sentence selection are the fundamental steps of a typical extractive document summarization algorithm.   The common text modeling method connects a pair of sentences based on their similarities.   Even thought it can effectively represent the sentence similarity graph of given document(s) its big drawback is a large time complexity of $O(n^2)$, where n represents the number of sentences.   The quadratic time complexity makes it impractical for large documents.   In this paper we propose the fast approximation algorithms for the text modeling and the sentence selection.   Our text modeling algorithm reduces the time complexity to near-linear time by rapidly finding the most similar sentences to form the sentences similarity graph.   In doing so we utilized Locality-Sensitive Hashing, a fast algorithm for the approximate nearest neighbor search.   For the sentence selection step we propose a simple memory-access-efficient node ranking method based on the idea of scanning sequentially only the neighborhood arrays.    Experimentally, we show that sacrificing a rather small percentage of recall and precision in the quality of the produced summary can reduce the quadratic to sub-linear time complexity.   We see the big potential of proposed method in text summarization for mobile devices and big text data summarization for internet of things on cloud.   In our experiments, beside evaluating the presented method on the standard general and query multi-document summarization tasks, we also tested it on few alternative summarization tasks including general and query, timeline, and comparative summarization.
Volume: 6
Issue: 3
Page: 945-954
Publish at: 2016-06-01

Performance Analysis of Digital Modulation for Coherent Detection of OFDM Scheme on Radio over Fiber System

10.11591/ijece.v6i3.pp1086-1095
Fauza Khair , Fakhriy Hario P , I Wayan Mustika , Budi Setiyanto
Radio over fiber (RoF) system with the coherent detection offers high linearity for the transparent transport of high-frequency microwave signals, and better receiver sensitivity compared with intensity-modulated direct detection systems. The purpose of this paper is to analyze the performance of digital modulation for coherent detection of orthogonal frequency division multiplexing (OFDM) scheme on RoF system at 10 Gbps up to 100 km fiber length. The results show that coherent detection of OFDM-RoF system with 16 quadrature amplitude modulation (16-QAM) has the value of  bit error rate (BER) and the symbol error rate (SER) is very low and its constellation is better compared with other modulation formats (4-QAM, quadrature phase shift keying (QPSK), 8-PSK and 16-PSK), which BER 16-QAM is 0.053 and SER is 15.7%. The results also show that BER value of 4-QAM and QPSK relatively similar to fiber length variations. In general, an increasing value of the BER and SER for each modulation format are almost equal to the fiber length of 60-70 km (Region I and II). However, there is a significant increase in the value of BER in fiber length of 80-100 km (Region III. A and III. B) for the modulation of 4-QAM, QPSK, 8-PSK, and 16-PSK.
Volume: 6
Issue: 3
Page: 1086-1095
Publish at: 2016-06-01

Estimation of Excitation Capacitance Requirement of an Isolated Multi-phase Induction Generator for Power Generation

10.11591/ijpeds.v7.i2.pp561-567
Alok Kumar Mohanty , K B Yadav
Self Excited induction generators are used in remote places for electrical power generation from both conventional as well as non-conventional sources. An Induction generator can operate as a capacitor excited machine provided the machine is driven beyond synchronous speed and a suitable capacitor is connected across its terminals. In this paper a technique has been proposed to estimate the values of excitation capacitances to maintain desired terminal voltages in a multi-phase induction generator. A mathematical model using nodal admittance technique of a six-phase induction generator has been analyzed. Genetic algorithm technique is applied here to obtain the unknown parameters and the capacitance requirements to obtain desired terminal voltages under various operating conditions.
Volume: 7
Issue: 2
Page: 561-567
Publish at: 2016-06-01

Referenced Approximation Technique for a Rom-Less Sweep Frequency Synthesizer

10.11591/ijece.v6i3.pp1213-1222
Atman Jbari , Larbi Bellarbi , Abdelhamid Errachid
The main goal of this paper is to present a novel ROM-less direct digital frequency synthesizer for sweep instrumentation systems. It provides a main sweep channel for frequency analysis and a reference channel for phase and amplitude measurement block operating at constant frequency. For phase to amplitude converter, we propose a new trigonometric approximation technique based on a set of reference angles. In addition, we present the design of the proposed synthesizer and its evaluation in Matlab-Simulink environment. The simulation results illustrate the performances and demonstrate the effectiveness of our proposed circuit.
Volume: 6
Issue: 3
Page: 1213-1222
Publish at: 2016-06-01

Permanent Magnet Synchronous Motor Design using Grey Wolf Optimizer Algorithm

10.11591/ijece.v6i3.pp1353-1362
Yannis L Karnavas , Ioannis D Chasiotis , Emmanouil L Peponakis
Common high-torque low-speed motor drive schemes combine an induction motor coupled to the load by a mechanical subsystem which consists of gears, belt/pulleys or camshafts. Consequently, these setups present an inherent drawback regarding to maintenance needs, high costs and overall system deficiency. Thus, the replacement of such a conventional drive with a properly designed low speed permanent magnet synchronous motor (PMSM) directly coupled to the load, provides an attractive alternative. In this context, the paper deals with the design evaluation of a 5kW/50rpm radial flux PMSM with surface-mounted permanent magnets and inner rotor topology. Since the main goal is the minimization of the machine's total losses and therefore the maximization of its efficiency, the design is conducted by solving an optimization problem. For this purpose, the application of a new meta-heuristic optimization method called “Grey Wolf Optimizer” is studied. The effectiveness of the method in finding appropriate PMSM designs is then evaluated. The obtained results of the applied method reveal satisfactorily enhanced design solutions and performance when compared with those of other optimization techniques.
Volume: 6
Issue: 3
Page: 1353-1362
Publish at: 2016-06-01

Two-way Mechanism to Enhance Confidentiality and Accuracy of Shared Information

10.11591/ijece.v6i4.pp1785-1791
Manash Pratim Dutta , Subhasish Banerjee , Swarnendu Kumar Chakraborty , Chandan Tilak Bhunia
As such internet and information technology have influenced the human life significantly thus the current technology cannot solely assure the security of shared information. Hence, to fulfil such requirements mass amount of research have been undertaken by various researchers among which one of the mechanisms is the use of dynamic key rather than static one. In this regard, we have proposed a method of key generation to provide the dynamic keys. The scheme not only can change the key but also provide the error control mechanism. At the end of this paper, a comparison with the existing techniques has also been made to prove the efficiency of the proposed scheme.
Volume: 6
Issue: 4
Page: 1785-1791
Publish at: 2016-05-14

Analysis and Design of High Gain NRI Superstrate Based Antenna for RF Energy Harvesting System

10.11591/ijeecs.v2.i3.pp647-656
K.K.A. Devi , C. H. Ng
A high gain patch antenna inspired by 4 layers of negative refractive index (NRI) metamaterial superstrate is proposed to operate at downlink radio frequency (RF) band (935 MHz to 960 MHz of GSM 900). The metamaterial unit cell consists of a nested split ring resonator (SRR) and strip line laminated on other side of FR4 substrate. The effective permittivity and permeability of the proposed unit cell are designed synchronously to approach zero, which leads the NRI superstrate to have impedance match with zero and negative refractive index.The NRI superstrate is studied using Fabry-Perot (F-P) resonant cavity. The gain is improved by 82.48% at the air gap of 55 mm in the desired frequency band.Therefore, the gain of the antenna is effectively enhanced based on the negative refractive index metamaterial. The measured radiation pattern and S parameter results also showed that it has good agreement with the simulation results.
Volume: 2
Issue: 3
Page: 647-656
Publish at: 2016-05-07

Hardware Implementation of Induction Motor using ANN Controller under Low Speed Operation

10.11591/ijeecs.v2.i3.pp522-529
Saranya R , Thangavel S
For the high performance drives the artificial neural network based Induction motor is proposed. During the load variation, the performance of the Induction motor proves to be low. Intelligent controller provided for controlling the speed of induction motor especially with high dynamic disturbances. An effective sensorless strategy based on artificial neural network controller is developed to estimate rotor’s position and to regulate the stator flux under low speed, helps to track the motor speed accurately during the whole operating region. The overall combination of this setup is simulated in the MATLAB/SIMULINK platform. Finally an experimental prototype of the proposed drive has been developed to validate the performance of Induction Motor and the dynamic speed response of Induction motor with proposed controller was estimated for various speed and found that the speed can be controlled effectively.
Volume: 2
Issue: 3
Page: 522-529
Publish at: 2016-05-07

Reducing Computational Complexity and Enhancing Performance of IKSD Algorithm for Encoded MIMO Systems

10.11591/ijeecs.v2.i3.pp636-646
Mohammed Qasim Sulttan
The main challenge in MIMO systems is how to design the MIMO detection algorithms with lowest computational complexity and high performance that capable of accurately detecting the transmitted signals. In last valuable research results, it had been proved the Maximum Likelihood Detection (MLD) as the optimum one, but this algorithm has an exponential complexity especially with increasing of a number of transmit antennas and constellation size making it an impractical for implementation. However, there are alternative algorithms such as the K-best sphere detection (KSD) and Improved K-best sphere detection (IKSD) which can achieve a close to Maximum Likelihood (ML) performance and less computational complexity. In this paper, we have proposed an enhancing IKSD algorithm by adding the combining of column norm ordering (channel ordering) with Manhattan metric to enhance the performance and reduce the computational complexity. The simulation results show us that the channel ordering approach enhances the performance and reduces the complexity, and Manhattan metric alone can reduce the complexity. Therefore, the combined channel ordering approach with Manhattan metric enhances the performance and much reduces the complexity more than if we used the channel ordering approach alone. So our proposed algorithm can be considered a feasible complexity reduction scheme and suitable for practical implementation.
Volume: 2
Issue: 3
Page: 636-646
Publish at: 2016-05-07

Model Predictive Current Control of Grid Connected PV Systems

10.11591/ijeecs.v2.i2.pp285-296
Satya Ravi Rai , Jaya Kumar S V , Keerthi Deepika K
This paper deals with the design and simulation of an efficient solar photovoltaic system with a maximum power point tracking system (MPPT). Maximum power point (MPP) is obtained by using Perturb and Observe (P&O) algorithm. The output from solar panel is fed to the DC-DC (Boost) converter which steps up the output voltage. It is then fed to a 3-phase inverter. The inverter used is a 3-phase two-level inverter implemented with a Model Predictive Control strategy. Model of the system is considered in order to predict the control variables. Optimum switching state is selected by minimizing the cost function for each sampling period. This is achieved through modelling and MATLAB simulation of various stages that constitute the overall system.
Volume: 2
Issue: 2
Page: 285-296
Publish at: 2016-05-01

Extension of Linear Channels Identification Algorithms to Non Linear Using Selected Order Cumulants

10.11591/ijeecs.v2.i2.pp334-343
Mohammed Zidane , Said Safi , Mohamed Sabri
In this paper, we present an extension of linear communication channels identification algorithms to non linear channels using higher order cumulants (HOC). In the one hand, we develop a theoretical analysis of non linear quadratic systems using second and third order cumulants. In the other hand, the relationship linking cumulants and the coefficients of non linear channels presented in the linear case is extended to the general case of the non linear quadratic systems identification. This theoretical development is used to develop three non linear algorithms based on third and fourth order cumulants respectively. Numerical simulation results example show that the proposed methods able to estimate the impulse response parameterswith different precision.
Volume: 2
Issue: 2
Page: 334-343
Publish at: 2016-05-01

A Power Efficient Trust Based SecureRouting Scheme for Mobile Ad-Hoc Networks

10.11591/ijeecs.v2.i2.pp417-425
M V Rathnamma , P. Chenna Reddy
MANETs are self-organizing, infrastructure less ad-hoc networks with many challenges like low power, limited storage and limited processing devices. Among all the parameters that affect the network efficiency accuracy, scalability, and power consumption are main challenges in the routing of Mobile ad-hoc networks. The network lifetime is dependent on the power efficiency of the nodes in the network. The protocols have to provide the energy efficient route through intermediate nodes in the network. The trust based routing approach is one of the best mechanisms to establish an energy efficient route between source and destination. In this paper we first propose the family relationship based trust model and then propose a new energy efficient trust based routing protocol to reduce the routing overhead, delay and provides better packet delivery ratio that performs better than the existing routing protocols.
Volume: 2
Issue: 2
Page: 417-425
Publish at: 2016-05-01

Reconfiguration of Distribution Networks with Presence of DGs to improving the Reliability

10.11591/ijeecs.v2.i2.pp241-247
Amir Sabbagh Alvani , Seyed Mehdi Mahaei
In this paper, the network reconfiguration in the presence of distributed generation units with the aim of improving the reliability of the network is studied. For this purpose four reliability parameters in the objective function are considered, which is average energy not supplied system average interruption frequency index, system average interruption duration index and momentary average interruption frequency index. The new method will be normalized objective function. Another suggestion of this paper are considering the different fault rates, locating time of faults type and prioritization of customers based on their importance. This nonlinear problem has optimized by particle swarm optimization (PSO) algorithm.
Volume: 2
Issue: 2
Page: 241-247
Publish at: 2016-05-01

Color Module Computer Aided Design in Indoor Environment

10.11591/ijeecs.v2.i2.pp461-468
Lifeng Pan
In this study, a comprehensive solution set of strategies is proposed for interior color design. Computer aided design methods are utilized to solve the problems in the color scheme process, the existing circumstances, shortage and trend of current color scheme tools are analyzed based on interior design theory and modern design methodology. The appropriative color space is constructd to redound the process of special color selection，the tone harmonizing tool is built based on architecture exterior design，and  the color  knowledge database and scheme database are contrived，the rationality of the color scheme method is validated by integrated cases, the effective way of computer aided color design is obtained and  this method is applied to the instance of interior design, it provides a key module for the interior design system software. In the design process, the factors are taken such as color space property，color harmonizing effect，color tone classification, material and texture effect,  a viable color enactment is provided for modern interior design.
Volume: 2
Issue: 2
Page: 461-468
Publish at: 2016-05-01

Improved UFIR Tracking Algorithm for Maneuvering Target

10.11591/ijeecs.v2.i2.pp344-350
Shoulin Yin , Jinfeng Wang , Tianhua Liu
Maneuvering target tracking is a target motion estimation problem, which can describe the irregular target maneuvering motion. It has been widely used in the field of military and civilian applications. In the maneuvering target tracking, the performance of Kalman filter(KF) and its improved algorithms depend on the accuracy of process noise statistical properties. If there exists deviation between process noise model and the actual process, it will generate the phenomenon of estimation error increasing. Unbiased finite impulse response(UFIR) filter does not need priori knowledge of noise statistical properties in the filtering process. The existing UFIR filters have the problem that generalized noise power gain(GNPG) does not change with measurement of innovation. We propose an improved UFIR filter based on measurement of innovation with ratio dynamic adaptive adjustment at adjacent time. It perfects the maneuvering detect-ability. The simulation results show that the improved UFIR filter has the best filtering effect than KF when process noise is not accurate.
Volume: 2
Issue: 2
Page: 344-350
Publish at: 2016-05-01
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