@article{ author = {Hanafizadeh, Payam}, title = {Taxonomy of Information Society Measures}, abstract ={To benefit from the advantages of information society on one hand, and afraid of being left further behind of Global Society and increasing in the digital divide on the other hand, stimulating countries to become inclusive Global Information Society. These issues have led policy makers to move towards such society by identifying the objectives, goals and targets. Planning for achieving these objectives needs a real understanding of current situation that can be obtained by information society measures. There has been a proliferation of information society measures in recent years that each of them follows a certain objective. This paper elaborates and categorizes these measures that help scholars and policy makers to 1) select the measures that fitted with their objectives, 2) prevent the repetitive researches, 3) identify the defects and flaws of previous measures and correct them in their own measures, 4) use the experiences of previous measures for constructing their own ones. In this paper, e-measures are classified in three categories: Digital Divide, E-Readiness, and Core ICT Indicators. The categorization of e-readiness measures are based on definitions of e-readiness, objectives, methods and results. Also, digital divide measures are categorized based on potential factors that include cross-sector and cross-construct validation studies.}, Keywords = { core ICT indicators, digital divide, e-readiness, information society measures }, volume = {3}, Number = {4}, pages = {1-12}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-197-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-197-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {Javani, Mehran and EftekhariMoghadam, Amir masou}, title = {An Image Annotation Method Based on CM Similarity Measure and Hybrid Relevance Feedback}, abstract ={Today, with the advent of digital imagery, the volume of digital images has been growing rapidly in different fields. So, there is an increasing need for providing an effective image retrieval system. In this paper, a semisupervised k-means clustering method was introduced for image database clustering and image annotation. One of the most important parts of image clustering algorithms is to determine similarity of the images. To compute exact similarity measures, a new CM similarity measure was proposed here to make normalized and weighted features simultaneously so that similarity measure exploits normalized or weighted features in its formula to reach better performance. However, due to semantic gap, some images may be false clustered. A hybrid of three relevance feedback (RF) schemes was used to improve the accuracy of image clustering. (1) The images with the user who knows their irrelevance to a cluster were conducted to correct cluster by a long-term RF. (2) With regard to the images with the user who knows they are relevant to a cluster, feature weight of the clusters was estimated in order to provide a multiple similarity measure using a re-weighting RF. (3) To discover the exact place of the cluster centers, a cluster center movement (CCM) RF was used. Experimental results based on the Corel database including 1000 images and a satellite image database of Tehran city including 2400 images demonstrated the superiority of the proposed method in image database clustering.}, Keywords = { Image retrieval, Relevance feedback, Image annotation, Image database clustering, Similarity measure }, volume = {3}, Number = {4}, pages = {13-25}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-198-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-198-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {TafaghodiKhajavi, Navid and SadeghiIvrigh, Siavash and Sadough, Seyed Mohammad Saj}, title = {An Improved Blind Spectrum Sensing Technique for Cognitive Radio Systems}, abstract ={Cognitive radio technology has been proposed as a key solution for the problem of inefficient usage of spectrum bands. Spectrum sensing is one of the most important issues in each cognitive radio system. Classically-used spectrum sensing techniques require that the cognitive transmitter is not in operation while detecting the presence/absence of the primary signal during the sensing period. In this paper, we propose to use blind source separation algorithms such as Kurtosis metric, STFD and TALS with the aim of improving the accuracy of conventional spectrum sensing techniques based on blind source separation. Using blind source separation algorithms, cognitive radio can sense a specific spectrum band while sending its own data in this band. We also introduce a new spectrum sensing framework that combines blind source separation with conventional spectrum sensing techniques. In this way, spectrum sensing can continue to work even when the cognitive transmitter is in operation. Simulation results provided in terms of receiver operating characteristic (ROC) curves indicate that the proposed method also improves the sensing performance achieved with conventional spectrum sensing techniques.}, Keywords = { Spectrum Sensing, Cognitive Radio, Blind Source Separation, Random Matrix Theory }, volume = {3}, Number = {4}, pages = {27-35}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-199-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-199-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {Vakil, Vahideh and Rahmati, Mehdi}, title = {Throughput Improvement of Cooperative System Using Adaptive Relaying & Adaptive Modulation}, abstract ={In this paper, adaptive modulation is implemented for a selection combining Demodulate and Forward Relay system. In this method, the source and relay select the modulation type based on the channel quality measurement, which is the output SNR, to improve the total throughput of the system. The adaptation thresholds are computed by solving an optimization problem. The model is generalized for the N-relay system and the optimization problem is modified for this case. Adaptive modulation is then employed for the N-relay DMF system. Adaptive relaying method is also proposed for adaptive modulated DMF system to achieve BER constraint, attain maximum possible throughput and reduce the complexity of hardware. Another optimization problem and several novel algorithms are generated in this paper, to perform adaptive relaying adaptive modulated DMF system. The results demonstrate that employing the proposed methods improves the total throughput of the system by keeping the BER performance at the target level.}, Keywords = { Adaptive modulation, Adaptive relaying, Cooperative communication, Demodulate and Forward Relay, Selection combining }, volume = {3}, Number = {4}, pages = {37-44}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-200-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-200-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {YaghmaeeMoghaddam, Mohammad Hossein and Adjeroh, Donal}, title = {Priority Based Congestion Control and Partial Reliability Guaranty Protocol for Wireless Multimedia Sensor Networks}, abstract ={Congestion is an essential problem in Wireless Sensor Networks (WSNs). It not only wastes the scarce energy due to a large number of retransmissions and packet drops, but also hampers the event detection reliability. Thus, to meet the Quality of Service (QoS) requirements for network applications, a reliable and fair transport protocol is mandatory. For some applications however, such as in wireless multimedia sensor networks, having a 100% packet delivery ratio is not necessary. In this paper, we present PCC-PRG, a Priority Based Congestion Control and Partial Reliability Guaranty protocol for wireless multimedia sensor networks. The proposed PCC-PRG protocol can be used for partial order services in WMSNs. PCC-PRG uses the maximum queue length of intermediate nodes to detect and notify congestion in the network. PCC-PRG protocol uses a rate control mechanism to adjust the transmission rate of each traffic flow based on the congestion degree in the network and also the flow priority. All transmitted packets are classified into two different priority groups: high and low. Only lost high priority packets are retransmitted. To use a node’s energy efficiently, we use a hop-by-hop NACK-based reliability guaranty model. Simulation results confirm the superiority of the proposed model.}, Keywords = { Wireless Multimedia Sensor Networks, Congestion Control, Reliability, Transport Protocols, Rate based control }, volume = {3}, Number = {4}, pages = {45-58}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-201-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-201-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {MoghaddamTabrizi, Mohammad and Masoumi, Nasser}, title = {Sensitivity Analysis of Shielded Coupled Interconnects for RFIC Applications}, abstract ={In this paper the sensitivity of on-chip interconnects to Si CMOS process parameters in two different test structures are reported; two coupled lines with shielding, and without shielding. Simulations are performed using HSpiceRF to emulate the state-of-the-art and the future technologies for the test structures. Some important parameters characterizing the coupled interconnects have been examined. Shielding effectiveness on crosstalk reduction is computed using HSpiceRF simulation results in order to compare the efficiency of shielding structures with different process parameters. Additionally we investigate the influence of the process parameters in deep sub-micron technologies on the transmission, reflection, near-end, and far-end crosstalk characteristics of the coupled interconnect with and without the presence of shielding lines.}, Keywords = { Interconnects, Shielding, Sensitiviy Analysis }, volume = {3}, Number = {4}, pages = {59-64}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-202-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-202-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {Nourafza, Nasim and Setayeshi, Saeed and KhademZadeh, Ahm}, title = {Design of a Cellular Sugarscape Environment to Increase the Learning Speed in a Stochastic Multi-agent Network}, abstract ={Sugarscape model is a multi-agent environment used for modeling and organizing processes such as social, political and economic processes .The purpose of this study is to assess the learning ability of a learner system in sugarscape and for that reason the Boltzmann machine learning algorithm is evaluated .During the first experience, model number 1 which is a learned multi-agent model and is based on Boltzmann machine algorithm was considered .In this model each agent, was assigned with a parameter which indicates the agent’s knowledge .Once the knowledge of agents reached the maximum, the model is converged .The criterion was time of convergence .After that, the second model which is a multi-agent, cellular, and learner based on Boltzmann machine learning algorithm was considered, in which the Boltzmann machine’s learning algorithm is implemented in a multi-agent cellular environment . And finally the third model which is a multi-agent, cellular, Boltzmann machine learner model was assessed in sugarscape. And measure the time needed to reach convergence over specific number of agents for each model. After investigating the resulting diagrams it was concluded that the convergence speed of third model is more than the convergence speed of second model .Also, the convergence speed of second model is more than convergence speed of first model .Utilization of cellular automata results in a more speedy convergence for the model and this is due to rules and local interactions and transformation of generalized convergence to localized convergences .Application of sugarscape accelerates convergence speed relative to the case when it is not used. Additionally the maximum number of executable agents in third model is more than second model and also the maximum number of executable agents in second model is much greater than the first model .At last, it was deduced that the learning process of a learned multi-agent system and in sugarscape speeds up this process and does not have the limitations in the number of agents during execution.}, Keywords = { multi-agent system, learning, Boltzmann Machine learning algorithm, cellular automata, sugarscape, convergence }, volume = {3}, Number = {4}, pages = {65-72}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-203-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-203-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {Arezumand, Hamid and Azmi, Paeiz and Sadeghi, Hame}, title = {A Low-Complexity Cyclostationary-Based Detection Method for Cooperative Spectrum Sensing in Cognitive Radio Networks}, abstract ={Fast reliable spectrum sensing (SS) is a crucial problem in the cognitive radio systems. To address this issue, cyclostationarity-based detection methods, which are generally more complex but more reliable than energy detection methods, have been proposed. This paper presents a new method to detect the presence of the second-order cyclostationarity in the OFDM-based primary user (PU) signals. The proposed method has a low computational complexity, while it presents a performance close to the well-known GLRT-based Dandawaté-Giannakis's method. Moreover, since the proposed low-complexity method is robust against the noise uncertainty, it can be a good alternative to the energy detection method. We further propose some cooperative spectrum sensing methods to improve the detection performance. Extensive simulation results confirm the superiority of the proposed schemes.}, Keywords = { Cooperative, Cyclostationarity-Based, Low-Complexity Spectrum Sensing, Soft Combination }, volume = {3}, Number = {3}, pages = {1-10}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-204-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-204-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {JamaliKooshkghazi, Vahid and Reisi, Nima and Ahmadian, Mahmoud and Salari, Soheil}, title = {Bayesian-Based Cooperative Framework for Spectrum Sensing in Cognitive Radio Networks}, abstract ={Energy detection has been adopted as an alternative spectrum sensing method for cognitive radios due to its low computational complexity and not requiring a priori information about the signal to be detected. However, noise uncertainty and hidden terminal problem make energy detector practically challenging specially in low signal-to noise ratio (SNR) regime. Collaboration among multiple cognitive radios has been recognized as a practical strategy to improve the reliability of spectrum sensing. In this paper, a cooperative spectrum sensing framework is proposed to blindly determine the occupancy of a wideband spectrum. Specifically, contrary to conventional energy detector, the proposed method does not require any knowledge of noise variance to detect the presence of primary signals. Moreover, diversity achieved by cooperation enables the framework to maintain a reasonable performance even in low SNR values. Simulation results confirm the effectiveness of our proposed method in improving both the probabilities of detection and false alarm.}, Keywords = { cognitive radio, cooperative spectrum sensing, energy detection, Generalized Bayesian estimator }, volume = {3}, Number = {3}, pages = {11-18}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-205-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-205-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {BalaneshinKordan, Saeid and Abolhassani, Bahm}, title = {A Novel Blind Spectrum Sensing Algorithm for Cognitive Radio Systems Based on Algorithmic Information Theory}, abstract ={In this paper، we propose a new algorithm of spectrum sensing based on algorithmic information theory. Since the proposed algorithm is applied in time domain، resulting in an overall reduction on the system computational complexity. In this paper، we investigate two cases of wideband and narrowband spectrum sensing problems. To sense the spectrum، we propose to use some measures based on algorithmic information theory such as Lempel-Ziv Complexity (LZC)، Higuchi fractal dimension (HFD)، and Algorithmic mutual information (algorithmic MI). LZC and HFD are reliable and promising measures that calculate the complexity of a time series signal in a straight forward manner. On the other hand، algorithmic MI calculates the algorithmic mutual information between two time series signals. Our proposed algorithm is blind in the sense that it requires no prior knowledge of the channel، primary users’ signals، and noise variance. In simulation section، it is shown that our proposed algorithm has better performance in contrast with the other complexity based detectors such as Shannon entropy and spectral entropy based detectors.}, Keywords = { Cognitive Radio, Blind Spectrum Sensing, Lempel-Ziv Complexity (LZC), Higuchi Fractal Dimension (HFD), Algorithmic mutual information, Entropy }, volume = {3}, Number = {3}, pages = {19-26}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-206-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-206-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {Hamedanian, Mahshad and Mohammadi, Abbas and Abdipour, Abdolali}, title = {Joint Antenna Selection and Adaptive Modulation in MIMO Systems in the Presence of CSI Imperfection}, abstract ={This paper presents a strategy to combine the antenna selection technique and the adaptive modulation method for multiple input multiple output (MIMO) systems. The MIMO architecture significantly improves the performance of wireless systems at the expense of a radio frequency (RF) hardware complexity. However, the advantages of MIMO systems can be mainly maintained with simple hardware using antenna selection technique. Moreover, in order to improve the efficiency, the adaptive modulation method can be implemented. As a practical system design limitation, the perfect channel state information (CSI) may not be achievable. Accordingly, the effect of imperfect channel state information (ICSI) in the proposed systems has been investigated.}, Keywords = { MIMO, antenna selection, adaptive modulation, CSI imperfection, spectral efficiency, bit error rate }, volume = {3}, Number = {3}, pages = {27-33}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-207-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-207-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {Beheshti, Seyed Mohsen and Mahboobi, Behrad and Ardebilipour, Mehr}, title = {Joint Power Adaptation and Interference Avoidance for Unlicensed Wireless Systems: A Game Theoretic Approach}, abstract ={In multiuser wireless systems, waveform adaptation is one of the interference management methods in which the users adaptively change their transmitting waveforms in signal space to enhance the system performance subject to some Quality-of-Service (QoS) requirements. In this paper, the uplink scenario of a Multi Carrier Code Division Multiple Access (MC-CDMA) is considered under slow and frequency selective fading. An admissibility test under maximum received power constraint is presented to check that if there exist feasiblepowers and waveforms for network users to hold the QoS constraint of each user above a predetermined level. In our set-up, a number of licensed (fixed) and unlicensed (agile) users share some orthogonal carriers to send data to a common receiver (or colocated independent receivers), subject to specific target SINRs for users. We analyze this system as a non-cooperative separable game and show the existence of Nash equilibrium point for this joint power control and codeword adaptation game.An iterative distributed algorithm based on better response strategy is presented which at the receiversresults in an ensemble of well-known Generalized Welch Bound Equality (GWBE) optimal waveforms and orthogonal waveforms for oversized users in addition to optimal transmission power for each user. We investigate the properties of fixed point and the effect of algorithm on the performance of fixed users’ network. Finally the algorithm will be confirmed by the numerical examples.}, Keywords = { Unlicensed communication, interference avoidance, MC-CDMA, waveform adaptation, transmitter optimization }, volume = {3}, Number = {3}, pages = {35-45}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-208-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-208-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {Banivaheb, Neda and Navaie, Keiv}, title = {A Stochastic Geometry Analysis of Hybrid Cellular-Adhoc CDMA Networks}, abstract ={This paper studies the impact of using multihop wireless adhoc network in conjunction with cellular networks under a probabilistic routing strategy. Our objective is to obtain the outage probability of the twodimensional hybrid CDMA network under path loss. In the proposed network the base stations are placed on a regular grid and users are distributed randomly according to a homogeneous Poisson point process. To obtain the outage probability of the proposed hybrid network, we study the outage probability of a cellular CDMA wireless network on both uplink and downlink as well as the outage probability of a multihop ad hoc CDMA network. We validate our analytical expressions via Monte Carlo simulations. Our results demonstrate that in order to improve the performance of a hybrid wireless network with a large density of users, it is beneficial to use multihop ad hoc communication.}, Keywords = { hybrid networks, stochastic geometry, point process }, volume = {3}, Number = {3}, pages = {47-54}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-209-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-209-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {SamsamiKhodadad, Farid and AbedHodtani, Ghosheh and HosseiniKarani, S. Bagher and KhoshbinGhasem, Hossei}, title = {A Novel DS-CDMA Direction of Arrival Estimator for Frequency- Selective Fading Channel with Correlated Multipath by Using Beamforming Filter}, abstract ={In this paper, a new method for estimating the direction of arrival of Asynchronous DS-CDMA signals in multipath fading channel is proposed. In the proposed method, first, for removing the effects of undesired paths, we project the coherent signals of the undesired paths perpendicularly to the under process signal, next, the signal is passed through a filter bank.Byusing beam forming filters, the effectof other users on the desired users signal is decreased and hence, the search area is decreased almost to one tenth. In this algorithm, searching all angles is not required,to estimate the number of sources does not require any information criteria, andalso, the number of users can exceed the number of antenna arrays contrary to many of the conventional methods. Simulation results are illustrated to confirm the efficiency of the method.}, Keywords = { Direction of arrival estimation, orthogonal projection, beam forming, frequency-selective fading channel }, volume = {3}, Number = {3}, pages = {55-62}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-210-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-210-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {Zeinolabedinzadeh, Saeed and Kamarei, Mahmou}, title = {An Improved Active Mixer Architecture for Millimeter Wave Applications}, abstract ={Modified active mixer architecture is presented in this paper which improves the gain and noise figure of the mixer considerably. The architecture of the mixer allows wide band operation from very low frequencies up to millimeter - wave regime. Also the proposed architecture makes it possible to use older process options for implementing high frequency mixers with acceptable performance. Simulations using 0.18u RF technology files show the efficiency of the mixer. The technology files are based on BSIM 3(V3.2) Accurate transistor and passive component models are obtained by augmenting the technology files with the results of Electromagnetic field solvers.}, Keywords = { Mixer, CMOS, Millimeter-Wave, gain, Noise Figure, Wide band Response, Electromagnetic field simulation }, volume = {3}, Number = {2}, pages = {1-9}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-211-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-211-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {Ghanadi, Mehdi and Banai, Ali and Henke, Heino and Yousefi, Behnaz}, title = {Low Cost Millimeter Wave Duplexer Design Using Mixed Mode Matching and Integral Contour Methods}, abstract ={A millimeter wave H-plane duplexer with E-plane filters has been designed. The channel filters are connected via a T-junction which is compensated by a cylindrical post and analyzed by integral contour method. Moreover, the junction discontinuity effects have been taken into account. The combination of filters and compensated T-junction allows for low-cost manufacturing. The E-plane filters are analyzed separately, by the mode matching method. The scattering parameters of the combination of filters and T-junction are obtained. The diameter and position of the compensating post and the length of the T-junction arms are optimized in order to achieve the desired performance. This procedure saves computational time and memory. The duplexer has been built for 38GHz and the theory was verified by measurements.}, Keywords = { Duplexer, E-plane filter, Mode matching, Integral contour }, volume = {3}, Number = {2}, pages = {11-18}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-212-en.html}, eprint = {}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {Khoshniyat, Hamed and Moradi, Gholamreza and Abdipour, Abdolali and Afrooz, Kambiz}, title = {Optimization and Fully Distributed Analysis of Single Pole Single Throw Traveling Wave Switchesat Millimeter Wave Frequency Band}, abstract ={In this paper, a fully distributed model for a single pole single throw traveling wave switch is introduced and important parameters of the switch such as insertion loss, isolation, and reflection coefficient are presented based on the lossy transmission line model of switch. The results of fully distributed model are compared with the semidistributed model's results and have good agreement with them. By applying the fully distributed model and calculating various switch's parameters as a function of the switch length and operating frequency, the optimum switch length and operating frequency are obtained versus the parameters of switch, especially the reflection coefficient and isolation in OFF and ON conditions.}, Keywords = { Distributed structure, single pole single throw (SPST) switch, traveling wave switch (TWSW), lossy transmission line model, semi-distributed model }, volume = {3}, Number = {2}, pages = {19-25}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-213-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-213-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {EslamiRasekh, Maryam and Shishegar, Amir Ahmad and Farzaneh, Forouhar}, title = {A Study of the Effect of Diffraction and Rough Surface Scattering Modeling on Ray Tracing Results in an Urban Environment at 60 GHz}, abstract ={Channel characterization is an important step in the design of wireless communication systems. While channel sounding procedures are a useful method in determining channel behavior, they also require expensive and time consuming procedures and equipment. Ray tracing has been an important substitute for measurement in deterministic channel modeling and characterization of the wireless channel. Much has been done to improve the precision and efficiency of this method for lower frequency bands (generally below 5 GHz) over the years. Recently, with the worldwide announcement of a broad unlicensed band in the millimeter wave spectrum around 60 GHz, a great amount of attention has been paid to this frequency band, previously considered un-utilizable ([I, 21). However some basic dissimilarity between the 60 GHz and UHF bands has brought about the need for modification of the methods previously used. In this paper the focus has been placed on two propagation mechanisms: diffraction and rough surface scattering, and the impact of each on over-all channel response predictions have been investigated.}, Keywords = { millimeter wave propagation, ray tracing, wireless communication, urban channel characterization }, volume = {3}, Number = {2}, pages = {27-33}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-214-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-214-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {Ghaderi, Mohammad Ali and Moshiri, Behzad and Yazdani, Nasser and TayefehMahmoudi, Maryam}, title = {Customizing Feature Decision Fusion Model using Information Gain, Chi-Square and Ordered Weighted Averaging for Text Classification}, abstract ={Automatic classification of text data has been one of important research topics during recent decades. In this research, a new model based on data fusion techniques is introduced which is used for improving text classification effectiveness. This model has two major components, namely feature fusion and decision fusion; therefore, it is called Feature Decision Fusion (FDF) model. In the feature fusion component, two well-known text feature selection algorithms, Chi-Square (X2) and Information Gain (IG) were used; this component applied Ordered Weighted Averaging (OWA) operator in order to make better feature selection. The second component, Decision fusion component, combined two kinds of results using the Majority Voting (MV) algorithm. The results were obtained with feature fusion and without feature fusion. To evaluate the proposed model, K-Nearest Neighbor (KNN), Decision Tree and Perceptron Neural Network algorithms were used for classifying Rueters-21578 dataset documents. Experiments showed that this model can improve effectiveness of text classification in accordance to both Microaveraged F1 and Macro-averaged F1 measures.}, Keywords = { Text classification, text categorization, document classification, document categorization, text feature selection, data fusion }, volume = {3}, Number = {2}, pages = {35-45}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-215-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-215-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {Samadian, Reza and Noorhoseini, Seyed Maji}, title = {Analysing Probabilistic Support Vector Machine Based Localization In Wireless Sensor Networks}, abstract ={Localizing sensors in a sensor network is one of the severe bottlenecks that must be dealt with, before exploiting these kinds of networks efficiently. While there has been many techniques and methods proposed for the issue, most of them suffer from low accuracy, or impose extra costs to the network. A Support Vector Machine (SVM) based method has already been proposed which uses machine learning techniques to achieve a fairly accurate estimate of the location of the nodes. In this paper, we propose to use probabilistic SVM, which is more powerful than the existing method. Moreover, an innovative post processing step called ARPoFiL will be proposed that provides even more improvement to the accuracy of the location of the sensor nodes. We will show analytically and experimentally that probabilistic SVM integrated with ARPoFiL completely outperforms the existing method, particularly in sparse networks and rough environments with lots of coverage holes.}, Keywords = { component, Wireless Sensor Networks (WSN), Support Vector Machine (SVM), Localization, Probabilistic SVM, Artificial Neural Networks (ANN) }, volume = {3}, Number = {2}, pages = {47-56}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-216-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-216-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {Basiri, Javad and Taghiyareh, Fattaneh and Siami, Mohammad and Gholamian, Mohammad Rez}, title = {Credit Scoring Using Colonial Competitive Rule-based Classifier}, abstract ={Credit scoring is becoming one of the main topics in the banking field. Lending decisions are usually represented as a set of classification tasks in consumer credit markets. In this paper, we have applied a recently introduced rule generator classifier called CORER1 (Colonial competitive Rule-based classifiER) to improve the accuracy of credit scoring classification task. The proposed classifier works based on Colonial Competitive Algorithm (CCA). In order to approve the CORER capability in the field of credit scoring, Australian credit real dataset from UCI machine learning repository has been used. To evaluate our classifier, we compared our results with other related well-known classification methods, namely C4.5, Artificial Neural Network, SVM, Linear Regression and Naive Bayes. Our findings indicate superiority of CORER due to better performance in the credit scoring field. The results also lead us to believe that CORER may have accurate outcome in other applications of banking.}, Keywords = { credit scoring, CORER, colonial competitive algorithm, rule-based classifier, classification, finance and banking }, volume = {3}, Number = {2}, pages = {57-65}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-217-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-217-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {Kaghazgaran, Parisa and Sadeghyan, Babak}, title = {Masquerade Detection Using GUI Events in Windows Systems}, abstract ={Masquerade attack in computer systems refers to the illegitimate user activities while pretending to be legitimate user. Detection of such attacks is done by discovering significant changes in user's behavior based on his profile. Profile is built by data produced from mouse, keyboard and other devices. In this paper we propose a practical approach for collecting GUI data and deriving useful parameters included both mouse and keyboard events from Windows OS. We model user identification and masquerade detection as a binary classification problem. Profiling and user classification is accomplished by use of Support Vector Machine (SVM) algorithm. Feature vectors are fed to SVM. The output is behavioral pattern which builds the profile. System is trained by normal behavior and detects deviations from profile. According to the results of implementation the proposed approach ensure detection rate up to 94% with few false alarm.}, Keywords = { Masquerade detection, Intrusion detection, Anomaly, Profile, Detection rate, GUI, Behavior }, volume = {3}, Number = {2}, pages = {67-71}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-218-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-218-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {kardan, Ahmad and TadayonTabrizi, Ghamarnaz and NaghibizadehMeybodi, Seyed Mohsen and Ghalamkari, Abdolrez}, title = {Knowledge Evaluation Based on Learner Assessment and Utilizing Fuzzy System to Increase the Accuracy of Evaluation}, abstract ={Learner knowledge evaluation is a process of decision making, personalization and adaptation of learning system. Generally, Traditional methods of knowledge evaluation use few variables in the evaluation process; For instance, the only parameter which is involved in the process is accuracy of answers. While, in case of increasing the accuracy of evaluation in this process, more variables need to be considered. Fuzzy system with ability to accept variety of input variables, inference and output generation, is a good option for the process of evaluation, such that in the recent years there are so much effort in the way of using fuzzy logic and its capabilities in knowledge evaluation that have been done so far. In this paper we will present a method to evaluate the knowledge of learner that by using fuzzy system in three phases which are fuzzification, inference engine, defuzzifaction with considering more variables like accuracy rate, importance and complexity of questions, performs the evaluation process. The prime features of the presented system are clarity, flexibility and simplicity in implementation.}, Keywords = { Knowledge Evaluation, Knowledge Assessment, E-Learning, Fuzzy Logic, Learner Modeling }, volume = {3}, Number = {1}, pages = {1-8}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-219-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-219-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {Ghorbani, Fatemeh and Montazer, Gholam Ali}, title = {Learners Grouping in E-Learning Environment Using Evolutionary Fuzzy Clustering Approach}, abstract ={Selection of appropriate learning objects and delivery of them to learners considering students' characteristics are known as a challenging task in e-learning systems. In design and development process of educational material, the attention must be focused on learner's characteristics and requirements which are defined in terms of content and learning style. To determine the best learning object, a model of learner can be constructed based on some learner's personal and behavioral features like learning styles, user's browsing history and user's prior knowledge. Grouping students based on their learning styles is one of appropriate approaches which have been followed in this area. However, some special characteristics and limitations of e-learning environments have led to the fact that any decision making and adaptation based only on static learning style recognition might be deficient. In this paper we introduce an evolutionary fuzzy clustering (EFC) method using genetic algorithm, in which learners are divided into some categories according to their behavioral factors and interactions with the system in order to adopt the most appropriate learning objects, methods, and recommendations. Results of the proposed method are compared with K-means and fuzzy C-means clustering methods using Davies-Bouldin cluster validity index and the comparison shows that EFC method has the better clustering performance than the others.}, Keywords = { E-Learning System, Learning Style, Grouping, Fuzzy clustering, Evolutionary Methods }, volume = {3}, Number = {1}, pages = {9-19}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-220-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-220-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {TayefehMahmoudi, Maryam and Taghiyareh, Fattaneh and NadjarAraabi, Babak}, title = {An Ontology-based Framework for Organizing Research Support Contents inE-Learning Environment}, abstract ={Transferring information in an organized and coordinated way is an effective factor in forming innovative mentality in learner. Content organization has a significant role on this mentality formation. The objective of content organization may be representing a description, analyzing a subject, presenting a justification, applying a reasoning style and consolidating a situation. The purpose of this study is to present a framework for organizing research support content, considering the projection of learner's reasoning style, content processing perspective, and existing features of content, onto research abilities. Applying these different orthogonal aspects may bring about a precise research ability. In order to provide an efficient research support e-learning environment, it is necessary to enrich a traditional education system with research support services. Such an enriched environment affects mental/practical ability of researcher as well as accelerating research process through decreasing time, cost and energy.}, Keywords = { Content organization, intelligent content organization, e-learning, research support content, research ability improvement }, volume = {3}, Number = {1}, pages = {21-31}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-221-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-221-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {MirsaeedGhazi, Tahereh and Kharrat, Mahmood and Kardan, Ahmad and Eghbali, Ne}, title = {A Framework for Learner Preparation and Support in Academic E-learning Environment}, abstract ={E-learning as a modern educational system has certain components, and adopting this system will affect the conditions and characteristics of administrative aspects of the educational systems. Some of the critical educational factors such as requirements/ necessary skills /capabilities/ admission factors and learner capabilities/ characteristics will evolve significantly in this modern educational paradigm. The main objective of this paper is to present a framework for main indices and factors regarding e-learner readiness evaluation and also identifying the learners' skills, capabilities and limitations in a way to enable e-learning system administrators to provide preparation and support services for improving learning quality. In this paper, through a survey of e-learners' readiness characteristics, a framework for e-learners' primary preparation and corresponding guidelines for e-learners' support is proposed which is based on level of readiness. The proposed framework is targeted to academic courses, though its analysis mechanism can be easily workable for other educational courses as well.}, Keywords = { E-learning, learner's readiness, e-learning support, e-learning readiness framework }, volume = {3}, Number = {1}, pages = {33-41}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-222-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-222-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {Haghshenas, Ehsan and Mazaheri, Arya and Gholipour, Ameneh and Tavakoli, Maryam}, title = {An Intelligent Method for Customizable Adaptive Learning Content Generation}, abstract ={E-learning environments are being used more efficiently by the rapid growth in internet and multimedia technologies. Adaptive learning is a kind of learning environment which provides individual learning. It can customize the learning style according to the individual's personality and characteristics. Although there are a lot of e­learning systems having adaptive learning feature, they do not satisfy all adaptive learning aspects. This paper proposes a new method which tries to help learners find educational contents adapted to their personalities in an efficient manner. Our proposed method has four essential parts: 1) It finds out learner's features by MBTI and Kolb learning style tests or Bayesian networks. 2) Then It tries to select the most appropriate adaptive learning objects with 0/1 knapsack problem in a limited amount of time determined by learner. 3) An ant colony optimization algorithm is proposed to solve 0/1 knapsack problem efficiently. 4) Selected learning objects are then sequenced in order to preserve the prerequisites. Also we created a software application based on this method called BehAmooz for learners to find and comprehend the educational contents effectively. The results obtained by experimentations showed that this method could satisfy most of the students.}, Keywords = { £-learning, Adaptive learning, MBTI test, Kolb test, Bayesian networks, 0/1 Knapsack, Ant Colony Optimization (ACO), Sequencing }, volume = {3}, Number = {1}, pages = {43-55}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-223-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-223-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {Orooji, Fatemeh and Taghiyareh, Fattaneh}, title = {Investigating Students\' Temporal Behaviors and Evaluation of Faculty through Educational Data Mining}, abstract ={Educational data mining (EDM) extracts implicit and interesting patterns from large data collections to provide a more effective learning environment. Introducing EDM concepts and techniques, this paper aims to discover existing behavioral pattern of students in course selection and faculty evaluation as well as educators policies in grading. This study has been carried out to determine the correlation between Student Evaluation of Teachers (SET) ratings and their gained scores in University of Tehran, department of Information Technology engineering. Dividing students based on their grades, a weak direct relationship has been demonstrated among weak and good students (0.086, 0.108) meaning that the more students' grades were, the higher teacher evaluation scores were observed. Insufficient students' awareness of SET importance and the existence inappropriate questions beyond students' knowledge in the questionnaire may cause these results. Recognizing effective factors in SET ratings can reveal the strengths and weaknesses of this kind of faculty evaluation and provide the possibility for better planning and obtaining authentic results.}, Keywords = { educational data mining, student behavior, teacher evaluation, sequence pattern }, volume = {3}, Number = {1}, pages = {57-65}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-224-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-224-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {Sulaimany, Sadegh and Maghsoudi, Behrooz and Amiri, Ali}, title = {Improving the Performance of E-Learning Systems Using Extracted Web Server Log File Suggestions}, abstract ={There are many opportunities to improve E-Learning web-based applications with regard to continue challenges e.g. their lack of interaction between teachers and students and structural evaluation of the presented learning activity. In this paper, E-Learning system web server log data and information about its control panel are provided; then the gathered data were preprocessed. After extracting association rules form these data and selecting results using more confidence coefficients, they were used as a virtual consultant for improving the E-Learning system. MySQL was used as the database for storing and extracting patterns. Extracting association rules with more confidence coefficients was done using Weka Software. The selected E-Learning web application was Moodie and the virtual university case study was Iran University of Science and Technology. The obtained results showed the needs which cannot be granted by a human consultant easily and cannot be inferred from current application log directly.}, Keywords = { E-Learning systems, Web server log data, Data mining }, volume = {3}, Number = {1}, pages = {67-72}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-225-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-225-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} } @article{ author = {Kardan, Ahmad and Hendijanifard, Fatemeh}, title = {Expert Finding System in E-Learning: Using Concept Maps}, abstract ={Finding subject experts for problem solving is an important issue in e-learning environment. In e-learning environment there is no direct way to find the superior individuals. The current methods like analyzing the discussions or considering the learner actions need a lot of data or have some limitations. In this work, concept maps are utilized to define the experts in an e-learning environment. Concepts maps are graphical explanation of the meaningful relationship among the concepts. 35 M.Sc. and B.Sc. students participated in this work. The test design, implemented software, results and conclusions are described in detail in this article. The novelty of this work is the application of concept maps to find the experts, the combined presented models for concept map construction, and presenting a research methodology in this area.}, Keywords = { e-learning, concept map, expert finding, concept map assessment }, volume = {3}, Number = {1}, pages = {73-81}, publisher = {ICT Research Institute(ITRC)}, url = {http://ijict.itrc.ac.ir/article-1-226-en.html}, eprint = {http://ijict.itrc.ac.ir/article-1-226-en.pdf}, journal = {International Journal of Information and Communication Technology Research}, issn = {2251-6107}, eissn = {2783-4425}, year = {2011} }