Research Volumes :: Journal of Theoretical and Applied Information Technology (JATIT)

Journal of Theoretical and Applied Information Technology September 2010 | Vol. 19. No.1

Paper ID:	1352 -JATIT-2K10
Title:	INVESTIGATING THE IMPACT OF SPECTRUM EFFICIENT OFDM-MIMO AND MC-CDMA-MIMO COMMUNICATION SYSTEM FOR ITS
Author:	NIRMALENDU BIKAS SINHA, M.MITRA
Source:	Journal of Theoretical and Applied Information Technology Vol 19. No. 1 -- 2010
Abstract	For future wireless communications systems, parameters like high transmission data rate, spectral efficiency, and reliability are extremely necessary. In a multipath wireless channel, deploying multiple antennas at both the transmitter and receiver help us achieve higher data rate without increasing the total transmission power or bandwidth. When perfect knowledge of the wireless channel conditions is available at the receiver, the capacity has been shown to grow linearly with the number of antennas. The implementation of wideband MIMO system imposes major challenge to hardware designers due to the huge processing power required for MIMO detection. This can be overcome by using optimizing channel coding and MIMO detection. Orthogonal frequency division multiplexing (OFDM) and multi-carrier code division multiple access (MC-CDMA) have been attracting much attention in this field of study. In this paper, a comparative study for OFDM-MIMO is presented regarding BER/PER performance and hardware complexity. All the simulations are conducted within MIMO-OFDM framework and with a packet structure similar to that of IEEE 802.11a/g standard. We have derived a channel capacity expression for MC-CDMA MIMO in a multi-user environment and confirmed by numerical evaluation that MC-CDMA MIMO provides a slightly higher capacity than OFDM MIMO assuming perfect ICI cancellation (ICIC) is always higher than or equal to that of OFDM MIMO. Furthermore, we compare the channel capacities of MIMO multiplexing and multiple single-input multiple output (SIMO) system. As per the results obtained, the MC-CDMA-MIMO appears to be an affordable solution for wideband MIMO system targeting Giga-bit speed wireless transmission and ITS applications
Keywords	CDMA, OFDM, MIMO, V-BLAST and ITS
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Journal of Theoretical and Applied Information Technology September 2010 | Vol. 19. No.1

Paper ID:	1431 -JATIT-2K10
Title:	MODIFIED SEQUENTIAL ALGORITHM USING EUCLIDEAN DISTANCE FUNCTION FOR SEED FILLING
Author:	SAADIA SADDIQUE, MALIK SIKANDAR HAYAT KHIYAL, AIHAB KHAN, MEMOONA KHANUM
Source:	Journal of Theoretical and Applied Information Technology Vol 19. No. 1 -- 2010
Abstract	Euclidean Distance Transform has been widely studied in computational geometry, image processing, computer graphics and pattern recognition. Euclidean distance has been computed through different algorithms like parallel, linear time algorithms etc. On the basis of efficiency, accuracy and numerical computations, existing and proposed techniques has been compared. This study proposed a new technique of finding Euclidian distance using sequential algorithm. An experimental evaluation has shown that proposed technique has reduced the drawbacks of existing techniques. And the use of sequential algorithm scans has reduced the computational cost.
Keywords	Euclidean Distance Transformation, Image Processing, Image Transformation, Sequential Algorithm
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Journal of Theoretical and Applied Information Technology September 2010 | Vol. 19. No.1

Paper ID:	1307 -JATIT-2K10
Title:	RADIATION EXPOSURE OF CELL PHONES & ITS IMPACT ON HUMAN HEALTH – A CASE STUDY IN SOUTH ASIA (BANGLADESH) AND SOME RECOMMENDATIONS
Author:	A.S.M. IFTEKHAR UDDIN, JANNATUL FERDOUS
Source:	Journal of Theoretical and Applied Information Technology Vol 19. No. 1 -- 2010
Abstract	This paper goes for a simple but elaborate measurement of the sensitivity of human health due to the radiation of mobile phone while using it. The possible risks by radio frequency electromagnetic field exposure of the human body are a major concern for the society. If exposure is sufficiently intense, it can cause biological effects. The increasing use of mobile phone in our environment it is one of the reasons why many scientists believe some disease rates are on the rise. It is scientifically proved that the radiations produced by the mobile phones affect especially the brain of human being and it will give them the difficulty to cope up with their systematized daily course of action and soon cause health injury. In this paper, it has been shown that there lies a tangible congruence of the result of statistical analysis based on an extensive survey all over Bangladesh on different level of mobile users with the hazards.
Keywords	Radiation, Cell Phones, Biological Effects, Health, Statistical Analysis
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Journal of Theoretical and Applied Information Technology September 2010 | Vol. 19. No.1

Paper ID:	1429 -JATIT-2K10
Title:	ON THE CORRECTNESS OF FIREWALL POLICY DEPLOYMENT
Author:	M. EL MARRAKI, A. KARTIT
Source:	Journal of Theoretical and Applied Information Technology Vol 19. No. 1 -- 2010
Abstract	Firewall policies can contain several thousand rules due to the large size and complex structure of modern networks. The size and complexity of these policies require automated tools providing a user-friendly environment to specify, configure and safely deploy a target policy. In this paper, we show that naïve deployment approaches can easily create a temporary security hole by permitting illegal traffic or interrupt service by rejecting legal traffic during the deployment. We make some contributions to the correctness of firewall policy deployments and we show that the category of type I policy editing is wrong and could lead to security vulnerabilities. We then provide a correct algorithm for publishing political class type I. Our algorithm can be used even for the deployment of policies whose size is very important.
Keywords	Policy Deployment (PD), Firewall Policy Management (FPM), Network Security (NS)
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Journal of Theoretical and Applied Information Technology September 2010 | Vol. 19. No.1

Paper ID:	-JATIT-2K10
Title:	PEAK TO AVERAGE POWER RATIO REDUCTION IN OFDM SYSTEM USING ROBUST ESTIMATOR
Author:	A. A. ABDUL WAHAB, M. F. AIN
Source:	Journal of Theoretical and Applied Information Technology Vol 19. No. 1 -- 2010
Abstract	Orthogonal Frequency Division Multiplexing (OFDM) is a spectrally efficient multicarrier modulation technique for high speed data transmission over multipath fading channels. High Peak-to-Average Power Ratio (PAPR), which leads to power inefficiency in the RF portion of the transmitter, is a major drawback of OFDM. Lots of PAPR reduction techniques are proposed in literatures in last two decades. For instance, amplitude clipping, companding, coding, partial transmit sequence,selected mapping (SLM), interleaving, etc. This paper introduced an improved PAPR reduction scheme using robust estimator or trimmed mean. A truncated mean or trimmed mean is a statistical measure of central tendency, much like the mean and median. It involves the calculation of the mean after discarding given parts of probability distribution or sample at the high and low end, and typically discarding an equal amount of both. The trimmed mean is a useful estimator because it is less sensitive to outliers than the mean but will still give a reasonable estimate of central tendency or mean for many statistical models. Furthermore, there is no need for side information, and no loss in terms of data rate. Simulation results show that more than 1.2 dB reduction in the PAPR value can be achieved using the proposed method.
Keywords	Orthogonal Frequency Division Multiplexing (OFDM), Peak to Average Power Ratio (PAPR), Trimmed Mean
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Journal of Theoretical and Applied Information Technology September 2010 | Vol. 19. No.1

Paper ID:	1351 -JATIT-2K10
Title:	A MORE APPROPRIATE PROTEIN CLASSIFICATION USING DATA MINING
Author:	MUHAMMAD MAHBUBUR RAHMAN, ARIF UL ALAM, ABDULLAH-AL-MAMUN, TAMNUN E MURSALIN
Source:	Journal of Theoretical and Applied Information Technology Vol 19. No. 1 -- 2010
Abstract	Research in bioinformatics is a complex phenomenon as it overlaps two knowledge domains, namely, biological and computer sciences. This paper has tried to introduce an efficient data mining approach for classifying proteins into some useful groups by representing them in hierarchy tree structure. There are several techniques used to classify proteins but most of them had few drawbacks on their grouping. Among them the most efficient grouping technique is used by PSIMAP. Even though PSIMAP (Protein Structural Interactome Map) technique was successful to incorporate most of the protein but it fails to classify the scale free property proteins. Our technique overcomes this drawback and successfully maps all the protein in different groups, including the scale free property proteins failed to group by PSIMAP. Our approach selects the six major attributes of protein: a) Structure comparison b) Sequence Comparison c) Connectivity d) Cluster Index e) Interactivity f) Taxonomic to group the protein from the databank by generating a hierarchal tree structure. The proposed approach calculates the degree (probability) of similarity of each protein newly entered in the system against of existing proteins in the system by using probability theorem on each six properties of proteins. This function generates probabilistic value for deriving its respective weight against that particular property. All probabilistic values generated by six individual functions will be added together to calculate the bond factor. Bond Factor defines how strongly one protein bonds with another protein base on their similarity on six attributes. Finally, in order to group them in hierarchy tree, the aggregated probabilistic value will be compared with the probabilistic value of the protein that resides at the root. If there is no root protein (i.e. at the initial state), the first protein will be considered as the root and depending on the probabilistic value it can change its relative position. Recursively, at each node, we have applied this technique to calculate the highest probable position for a particular protein in the tree.
Keywords	Bioinformatics, Protein, Protein Grouping Techniques, PSIMAP, Scale Free Protein
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Journal of Theoretical and Applied Information Technology September 2010 | Vol. 19. No.1

Paper ID:	1428 -JATIT-2K10
Title:	ON IMPROVED EXAMPLE-BASED SEARCH IN DIGITAL LIBRARIES VIA TERM RANKING
Author:	SULIEMAN BANI-AHMAD, GHADEER AL-DWEIK
Source:	Journal of Theoretical and Applied Information Technology Vol 19. No. 1 -- 2010
Abstract	Example-based searching, where user provides an example publication to locate similar publications to, is becoming commonplace in literature digital libraries. Two approaches to estimate similarities between publications are (i) graph based approaches where citation relationships amongst publication are used to compute similarities, and (ii) text-based approaches where observing shared terms between publications is used as indicator of similarity. In this paper we introduce a new text-based publication-similarity measuring technique that enhances existing example-based searching through utilizing term importance information. Term importance is computed via a proposed graph-based term ranking (GBTR) algorithm. The GBTR algorithm is different from previous term ranking approaches as it recursively computes term importance from the entire publication where it is observed, rather than relying only on local specific information. GBTR works well when paired with Okapi BM25. We exhaustively evaluate the performance of GBTR and compare it against the performance of existing term-ranking methods such as the Chronological Term Rank (CTR) and the Term Proximity models. Significant improvements, in terms of precision, over existing approaches are observed. GBTR achieved around 10% improvement in precision over CTR and around 2% over TP with much less computational time and space complexity than the TP approach.
Keywords	Okapi system, BM25, Text retrieval, Example-based search, TextRank, Term Proximity.
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Journal of Theoretical and Applied Information Technology September 2010 | Vol. 19. No.1

Paper ID:	1337-JATIT-2K10
Title:	POWER QUALITY IMPROVEMENT USING A FUZZY LOGIC CONTROL OF A SERIES ACTIVE FILTER
Author:	S.S. MORTAZAVI , M. RAZAZ, AND E. KHAVARI
Source:	Journal of Theoretical and Applied Information Technology Vol 19. No. 1 -- 2010
Abstract	A fuzzy logic controller (FLC) with fast reference voltage generation to correct and regulate unbalance voltage in three-phase system is proposed. The compensation algorithm is not based on three-symmetrical component decomposition so the controller can yield a fast response that is essential in such a critical real time control work. The reference voltage is fed to the FLC , which is a robust closed loop controller. The proposed algorithm and control scheme of series active filter may correct and regulate unbalance voltage in three-system under different conditions of the utility supply.
Keywords	Series Active Filter, Fuzzy Logic Control, Power Quality Improvement, Voltage Unbalance
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Journal of Theoretical and Applied Information Technology September 2010 | Vol. 19. No.1

Paper ID:	1400 -JATIT-2K10
Title:	USING NEW DATA STRUCTURE TO IMPLEMENT DOCUMENTS VECTORS IN VECTOR SPACE MODEL IN INFORMATION RETRIEVAL SYSTEM
Author:	Dr. Khalaf Khatatneh, M.Wedyan, Dr.Mohamed Alham, Dr.Basem Alrifai
Source:	Journal of Theoretical and Applied Information Technology Vol 19. No. 1 -- 2010
Abstract	In this paper, we present how table memorized semiring structure contributes in the vector space model in information retrieval system. We implement this new structure by generating table for each document and the first row filled with key word and the second row filled with weight for each word. This new structure implements using 242 Arabic documents which were presented in the Saudi Arabian National Computer Conference. The new method (technique) shows a new result which is more efficient than traditional structure and can save space. The results also show that when we used traditional structure system it occupies 204248 × units to implement vectors, but in new data structure system it occupies 5388×unit which means that we saved more than 198860 space units.
Keywords	Stop Words, Memorized Semirings, Vector Space Model, Stopwords
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