Статьи журнала - International Journal of Information Technology and Computer Science
Все статьи: 1195
Several cancer classifiers combined with PLS-DR for base on gene expression profile
Статья научная
It is known that Logistic Regression coupled with Partial Least Squares dimension reduction (PLSDR-LD) is capable of extracting a great deal of useful information for classification from gene expression profile and getting a rather high classification accuracy rate. In this study, we replace the logistic function of Logistic Regression with several functions which are similar to logistic function in appearance, and apply these functions to the analysis of microarray data sets from two cancer gene expression studies. We compare these newly introduced models with PLSDR-LD proposed in the literature. The most effective models with good prediction precision are lastly provided through analyzing the results of two experiments.
Бесплатно
Shape Classification Based on Normalized Distance and Angle Histograms Using PNN
Статья научная
This study presents an attempt to develop a reliable computerized algorithm, which could classify images into predetermined classes. For this purpose, the histogram of the normalized distance between each two points of the image (algorithm I) and the histogram of normalized distances between three points and the normalized angle of the image edge points (algorithm II) are analyzed. The probabilistic neural network (PNN) is implemented to do shape classification. Our proposed approach is tested on ten classes of MPEG-7 image database. It has been shown that feature extraction based on the distance histogram (algorithm I and algorithm II) is efficient due to its potential to preserve interclass and intra-class variation. In addition, these algorithms ensur invariance to geometric transformations (e.g. translation, rotation and scaling). The best classification accuracy is achieved by eight classes with the total accuracy of 90% and 92.5% for algorithm I and algorithm II, respectively. The reported experiment reveal that the proposed classification algorithm could be useful in the study of MPEG-7 shapes.
Бесплатно
Shortcomings of ultrasonic obstacle detection for vehicle driver assistance and profiling
Статья научная
Obstacle detection is a challenging problem that has attracted much attention recently, especially in the context of research in self-driving car technologies. A number of obstacle detection technologies exist. Ultrasound is among the commonly used technologies due to its low cost compared to other technologies. This paper presents some findings on the research that has been carried out by the authors with regard to vehicle driver assistance and profiling. It discusses an experiment for detection of obstacles in a vehicle driver’s operational environment using ultrasound technology. Experiment results clearly depict the capabilities and limitations of ultrasound technology in detection of obstacles under motion and obstacles with varied surfaces. Ultrasound’s wavelength, beam width, directionality among others are put into consideration. Pros and cons of other technologies that could replace ultrasound, for instance RADAR and LIDAR technologies are also discussed. The study recommends sensor fusion where several types of sensor technologies are combined to complement one another. The study was a technical test of configurable technology that could guide future studies on obstacle detection intending to use infrared, sound, radio or laser technologies particularly when both the sensor and obstacle are in motion and when obstacles have differing unpredictable surface properties.
Бесплатно
Similar Words Identification Using Naive and TF-IDF Method
Статья научная
Requirement satisfaction is one of the most important factors to success of software. All the requirements that are specified by the customer should be satisfied in every phase of the development of the software. Satisfaction assessment is the determination of whether each component of the requirement has been addressed in the design document. The objective of this paper is to implement two methods to identify the satisfied requirements in the design document. To identify the satisfied requirements, similar words in both of the documents are determined. The methods such as Naive satisfaction assessment and TF-IDF satisfaction assessment are performed to determine the similar words that are present in the requirements document and design documents. The two methods are evaluated on the basis of the precision and recall value. To perform the stemming, the Porter’s stemming algorithm is used. The satisfaction assessment methods would determine the similarity in the requirement and design documents. The final result would give a accurate picture of the requirement satisfaction so that the defects can be determined at the early stage of software development. Since the defects determines at the early stage, the cost would be low to correct the defects.
Бесплатно
Simple detection and classification of road lanes based on image processing
Статья научная
Road accidents, besides being one of the main causes of mortality, have an economic impact on vehicle owners. Several conditions as driver imprudence, road conditions and obstacles are the main factor that will cause accidents. The most important automotive industries are incorporating technology to reduce risk in vehicles. In this way, lane detection systems have important attention, because from this data is possible to determine risk situations such as presence of obstacles, incorrect lane changes or lane departures. This paper proposes a technique for lane detection, based on image processing, which allows identifying the position of lateral lanes and their type. The method is composed of four stages: edge enhancement, potential lanes detection, post-processing and color lane estimation. The method was proved using image dataset and video captures over 12.000 frames. The accuracy of the system was of 91.9%.
Бесплатно
Simulation Based Comparison of Geo-Location Methods in Wireless Networks
Статья научная
There are many Geo-Location techniques proposed in cellular networks. They are mainly classified based on the parameters used to extract location information. In this study it is tried to have a new look to these positioning methods and to classify them differently regardless of parameters type. We classified these techniques base on mathematical algorithms which is used to derive location information of users in the network. Such algorithms are divided into three main subclasses in here, estimation theory based (MUSIC, ESPIRIT), Meta-heuristic (Genetic, PSO...) and filtering approaches (Kalman, Particle, Grid, MH ). The proofs and details of how to apply techniques are presented and the simulation results are given.
Бесплатно
Simulation and Tuning of PID Controllers using Evolutionary Algorithms
Статья научная
The Proportional Integral Derivative (PID) controller is the most widely used control strategy in the Industry. The popularity of PID controllers can be attributed to their robust performance in a wide range of operating conditions and partly to their functional simplicity. The process of setting of PID controller can be determined as an optimization task. Over the years, use of intelligent strategies for tuning of these controllers has been growing. Biologically inspired evolutionary strategies have gained importance over other strategies because of their consistent performance over wide range of process models and their flexibility. The level control systems on Deaerator, Feed Water Heaters, and Condenser Hot well are critical to the proper operation of the units in Nuclear Power plants. For Precise control of level, available tuning technologies based on conventional optimization methods are found to be inadequate as these conventional methods are having limitations. To overcome the limitations, alternate tuning techniques based on Genetic Algorithm are emerging. This paper analyses the manual tuning techniques and compares the same with Genetic Algorithm tuning methods for tuning PID controllers for level control system and testing of the quality of process control in the simulation environment of PFBR Operator Training Simulator(OTS).
Бесплатно
Simulation of the operation of induction machines at frequencies other than 50 Hz
Статья научная
In the paper is proposed an induction machine model that corresponds to operating conditions at the change of frequency. The applicability of simulation method for the analysis of its operation at the frequencies other than 50 Hz was examined. The operation of the induction machine which control parameter is the frequency of controlled current was particularly analyzed. The evaluation of the proposed model was performed using the adapted subprogram in the psbdrive MATLAB Simulink package. For the verification of the results, the method of verified simulation was used, as a part of the method which was derived from the artificial intelligence algorithm. It has been confirmed that by controlling the frequencies and current of the induction machine, the ability to work in overloads can be maintained and this type of control has certain advantages in the frequency regulation of the drive with variable loads.
Бесплатно
Single Channel Speech Separation Using an Efficient Model-based Method
Статья научная
The subject of extracting multiple speech signals from a single mixed recording, which is referred to single channel speech separation, has received considerable attention in recent years and many model-based techniques have been proposed. A major problem of most of these systems is their inability to deal with the situation in which the signals are combined at different levels of energies because they assume that the data used in the test and training phase have equal levels of energies, where, this assumption hardly occurs in reality. Our proposed method based on MIXMAX approximation and sub-section vector quantization (VQ) is an attempt to overcome this limitation. The proposed technique is compared with a technique in which a gain adapted minimum mean square error estimator is derived to estimate the separated signals. Through experiments we show that our proposed method outperforms this method in terms of SNR results and also reduces computational complexity.
Бесплатно
Six Algorithms for Frequency Offset Estimation in OFDM Systems
Статья научная
Generally, wireless systems suffer from Carrier Frequency Offsets (CFO), which results either from the receiver’s oscillator’s impairments or Doppler shifts. The frequency offset between transmitter and receiver local oscillator is a main drawback of OFDM systems. A frequency drift in the receiver’s oscillator would result in a frequency offset in the received signal, this offset consists of two parts: a Fine offset, as a fraction of OFDM subcarrier spacing, and a Coarse offset that is equal to an integer multiple of the subcarrier spacing. Coarse offsets results in two problems; firstly, the modulation symbols are located on the wrong frequency bins, secondly, the pilots used for channel estimation are misplaced leading to a faulty channel estimate and severe signal distortion by the Equalizer. Fine Offsets result in a loss of orthogonality and thus ICI (Inter-Carrier Interference), as the frequency bin of a certain modulation symbol would contain some information about the neighboring symbol bin.
Бесплатно
Smart Agent Learning based Hotel Search System- Android Environment
Статья научная
The process of finding the finest hotel in central location is time consuming, information overload and overwhelming and in some cases poses a security risk to the client. Over time with competition in the market among travel agents and hotels, the process of hotel search and booking has improved with the advances in technology. Various web sites allow a user to select a destination from a pull-down list along with several categories to suit one’s preference.. Some of the more advanced web sites allow for a search of the destination via a map for example hotelguidge.com and jamaica.hotels.hu. Recently good amount of work been carried in the use of Intelligent agents towards hotel search on J2ME based mobile handset which still has some weakness. The proposed system so developed uses smart software agents that overcomes the weakness in the previous system by collaborating among themselves and search Google map based on criteria selected by the user and return results to the client that is precise and best suit the user requirements. In addition, the agent possesses learning capability of searching the hotels too which is based on past search experience. The booking of hotel involving cryptography has not been incorporated in this research paper and been published elsewhere. This will be facilitated on Android 2.2-enabled mobile phone using JADE-LEAP Agent development kit.
Бесплатно
Smart PCS Based System for Oxygen Content Measurement
Статья научная
This paper presents the performance analysis of smart PCS based system for an accurate oxygen content measurement in the aqueous electrolyte solution. The system intends to measure the photo catalytic activity of the PCS which is sensitive to O2 by integrating the software and hardware design technique for more accurate results. The threshold voltage of the PCS changes due to photo catalysis process causing fluctuations in the PCS readout which is sensed by the microcontroller via an inbuilt 10 bit A/D converter. The digitized signal is processed and converted into corresponding value of O2 content. The proposed digital system is fast as compared to conventional flow injection analysis which is tiresome and time consuming job. The approach for this system relies on the fast operation of PCS which operates under sub threshold conditions and reduced computation time. The system is more user friendly and the outcomes of simulation are fairly in agreement with the theoretical estimations. The system is highly favourable for water quality monitoring applications due to reduced response time.
Бесплатно
Smart virtual expert system to assist psychiatrists (SVESTAP)
Статья научная
Psychological issues in the world are exponentially growing and the treatment gap is also comparatively high. The main reason would be the shortage of expertise and time-consuming in conventional diagnose process. The main objective of this research is to lower the mental issues treatment gap of professionals or apprentices in the field by creating a virtual expert system to assist psychiatrists. This system diagnoses most common mental disorders such as Depression Disorder, Anxiety Disorder, and Dementia. The proposed expert system can communicate with patients, to identify the current state of the illness. During the conversation, a standard questionnaire is given for the disease verification purpose. The experienced mental health professionals can use this expert system to assist in diagnosing process and the apprentices of the psychology can use this expert system as a training asset.
Бесплатно
Статья научная
As the information put together by the blend of smartphones, the cloud, the IOT, and ubiquitous computing continue to expand at an alarming rate, a data breach increases. Today, users' strong authentication and authorization approaches are increasingly important to secure sensitive, confidential, secret information. Possession and knowledge-based authentication techniques for computers, the internet, email accounts, etc., are commonly used to access vital information; they do not link a user to an established identity, resulting in most security vulnerabilities. Biometric authentication, on the other hand, has the privilege of being more reliable than traditional authentication as biometric characteristics of a person can’t be lost; they are tough to distribute, exchange or duplicate; and it requires the user to be present during the authentication process, thereby relating the users to established identities. Biometrics provides a higher level of assurance that the individual attempting to ascertain is the individual in question. Thus, resulting in a more reliable, usable, and cost-effective model with a higher level of protection to deter an attacker from obtaining entry to a computer or network and gaining access to confidential data. This paper introduces a novel fingerprint-based authentication scheme for mobile environments, enabling user authentication based on fingerprint features using a challenge-response-based authentication process. In this study, the proposed authentication system has been developed on a real Android-based smartphone, tested on actual users, and performance analysis has been carried out; empirical results reveal that the proposed authentication scheme achieves increased performance. Moreover, a usability analysis has been done to determine efficiency, effectiveness, and user satisfaction. The evaluation results indicate its feasibility to use it as an effective authentication mechanism for mobile phone environments.
Бесплатно
Статья научная
As we know, the datasets related to social networks are increasing. There are different procedures to analyze these types of datasets; one of these procedures is clustering which makes communities of social data. Random walk is a process which can find communities in a network, in other words when a random walk is used, it scans the nodes in some steps; it begins with an initial node and based on a random process progresses to neighboring nodes. In this paper an algorithm is proposed which aims to finding communities in a way that modularity factor increases, for this goal, random walks with random local search agent are combined. Experimental results show that the proposed method gives better modularity in comparison with other algorithms.
Бесплатно
Software Effort Estimation Using Grey Relational Analysis
Статья научная
Software effort estimation is the process of predicting the number of persons required to build a software system. Effort estimation is calculated in terms of person per month for the completion of a project. If any new project is launched into a market or in industry, then cost and effort of a new project will be estimated. In this context, a number of models have been proposed to construct the effort and cost estimation. Accurate software effort estimation is a challenge within the software industry. In this paper we propose a novel method, Grey Relational Analysis (GRA) to estimate the effort of a particular project. To estimate the effort of a project, traditional methods have been used as algorithmic models to evaluate the parameters of the basic model i.e. basic COCOMO model. In this paper, to show the minimum error rate we have used Grey Relational Analysis (GRA) to predict the effort estimation on Kemerer dataset. When compared to the traditional techniques for estimation, the proposed method proved better results. The efficiency of the proposed system is illustrated through experimental results.
Бесплатно
Software Implementation of Modular Reduction by Pseudo-mersenne Primes
Статья научная
Modern cryptosystems allow the use of operation in prime fields with special kind of modules that can speed up the prime field operation: multiplication, squaring, exponentiation. The authors took into account in the optimizations: the CPU architecture and the multiplicity of the degree of the modulus in relation to the machine word width. As example, shown adopted module reduction algorithms hard-coded for modern CPU in special form of pseudo-Mersenne prime used in MAC algorithm Poly1305, - in electronic signature algorithm EdDSA and - in short message encryption algorithm DSTU 9041. These algorithms have been software implemented on both 32-bit and 64-bit platforms and compared with Barrett modular reduction algorithm for different pseudo-Mersenne and generalized-Mersenne modules. Timings for proposed and Barrett algorithms for different modules are presented and discussed.
Бесплатно
Software Product Lines Composition through Partial Derivation
Статья научная
Software product line approach has been successfully adopted in various software domains. In some fields, single SPLs are no longer sufficient to fulfill their requirements due to the large variability amount they include. Consequently, a set of separated SPLs is built to handle this issue and construct what is known by Multi Product Lines (MPL). However, the emergence of MPLs results in several challenges, namely: managing the reuse between SPLs, structuring the MPL model and distributed derivation. In this paper, we propose a new approach for SPLs composition. Our approach relies on two main concepts: the separation of concerns and the partial derivation. It is validated in the context of an e-Learning MPL and an illustration is explained throughout the paper. The results show that our approach helps systemizing reuse within MPLs and structuring the MPL model. Moreover, SPLs are integrated early in the development process avoiding thus the distributed derivation challenges.
Бесплатно
Software Reliability Modeling using Soft Computing Techniques: Critical Review
Статья научная
Software reliability models assess the reliability by predicting faults for the software. Reliability is a real world phenomenon with many associated real-time problems. To obtain solutions to problems quickly, accurately and acceptably, a large number of soft computing techniques have been developed, but it is very difficult to find out which one is the most suitable and can be used globally. In this paper, we have provided an overview of existing soft computing techniques, and then critically analyzed the work done by the various researchers in the field of software reliability. Further to this, we have also compared soft computing techniques in terms of software reliability modeling capabilities.
Бесплатно
Solving Web-based Applications Architectural Problems in the Cloud: The Way Forward
Статья научная
Highly-available and scalable software systems can be a complex and expensive proposition. Traditional scalable software architectures have not only needed to implement complex solutions to ensure high levels of reliability, but have also required an accurate forecast of traffic to provide a high level of customer service. This traditional software architecture is built around a common three-tier web application model that separates the architecture into presentation, business logic and database layers. This architecture has already been designed to scale out by adding additional hosts at these layers and has built-in performance, failover and availability features. Even with all these developments in architectural designs, some software still lacks in scalability, reliability and efficiency. This paper therefore examines the shortfalls of traditional software architectural problems with a view to addressing them using the cloud computing approach.
Бесплатно
