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Features Subset Selection for Network Intrusion Detection Mechanism Using Genetic Eigen Vectors
No full textNetwork Intrusions are critical issues in computer and network systems. Several intrusion detection approaches be present to resolve these severe problems but the major problem is performance. To increase performance, it is significant to increase the detection rates and reduce false alarm rates in the area of intrusion detection. The recent approaches use Principal Component Analysis (PCA) to project features space to principal feature space and select features corresponding to the highest eigenvalues, but the features corresponding to the highest eigenvalues may not have the optimal sensitivity for the classifier due to ignoring many sensitive features. Instead of using traditional approach of selecting features with the highest eigenvalues such as PCA, we applied a Genetic Algorithm (GA) to search the principal feature space for genetic eigenvectors that offers a subset of features with optimal sensitivity and the highest discriminatory power. Therefore, in this research, a mechanism for optimal features subset selection is proposed to overcome performance issues using PCA, GA and Multilayer Perceptron (MLP). The KDD-cup dataset is used that is a benchmark for evaluating the security detection mechanisms. The MLP is used for classification purpose. The performance of this approach is addresses. Consequently, this method provides optimal intrusion detection mechanism which is capable to minimize amount of features and maximize the detection rate
Soft Vector Quantization with Inverse Power-Function Distributions for Machine Learning Applications
No full textThis paper discusses the positive impact of soft vector quantization on the performance of machine-learning systems that include one or more vector quantization modules. The most impactful gains here are avoiding over-fitting and boosting the robustness of such systems in the presence of considerable parasitic variance; e.g. noise, in the runtime inputs.
The paper then introduces a soft vector quantization scheme with inverse power-function distributions, and analytically derives an upper bound of its relative quantization noise energy to that of typical (hard-deciding) vector quantization. This relative noise is expressed as a closed-form function of the power in order to allow the selection of its optimal values of that compromise both a soft enough vector quantization with a stable performance via small enough relative quantization noise.
Finally, we present empirical evidence obtained via experimenting with two versions of the best reported OCR system for cursive scripts - that happened to deploy discrete HMMs - one version with hard vector quantization and the other with our herein presented soft quantization. Test samples of real-life scanned Arabic text pages are used to challenge both versions; hence the recognition error margins are compared
OFDM based Common Control Channel Design for Cognitive Radio Ad Hoc Networks
No full textCognitive radio (CR) technology allows devices to opportunistically use the vacant portions of the licensed wireless spectrum. However, the available spectrum changes dynamically with the primary user (PU) activity, necessitating frequent PU sensing coordination and exchanging network topology information in a multihop CR ad hoc network. To facilitate these tasks, an always-on, out-of-band common control channel (CCC) design is proposed that uses noncontiguous OFDM subcarriers placed within the guard bands separating the channels of the licensed spectrum. First, the task of choosing the OFDM-specific parameters, including the number, power, and bandwidth of the subcarriers is formulated as a feasibility problem to ensure that the CCC does not adversely interfere with the PU operation. Second, for unicast messaging between a given pair of users, a subset of the guard bands may be chosen, which allows an additional measure of protection for the adjacent PU spectrum. For this, the multiarm bandit algorithm is used that allows the guard band selection to evolve over time based on the observed interference from the PU. Results reveal that our proposed CCC ensures connectivity and improved PU protection with a limited trade-off in data rate when compared to frequency-hopping and cluster-based CCC schemes
Satisfaction and correlates of patients'
No full textObjectives: To estimate quantitatively consumers'
satisfaction and correlates of satisfaction with phYSicians
services provided by Ministry of Health Primary Health Ca
Centers in attending consumers.
Methods: Consumers (n=540) attending the selected
Primary Health Care Centers in Riyadh were asked abo
their satisfaction with physician's services. Eight Prima
Health Care Centers were randomly selected according to
geographical location, two from each geographical zone.
Seventy-five subjects were selected systematically where
every tenth Saudi aged 15 years and above who visited the
selected Primary Health Care Centers during the study period
was chosen. Data was collected via a self administered pilot
tested, internally consistent patient satisfaction questionnaire
which included socio-demographic characteristics as well as
the overall and differential satisfaction with the different
aspects of physicians' services in the selected Primary Health
Care Centers rated in a scale of 1-5 points, the higher the
score the higher the satisfaction.
Results: The results revealed that males constituted 60%,
and 58% of all patients were married, more than 60% were
employees and more than 70% have a monthly income of
less than 6000 Saudi Riyals. Almost 95% have an open file in
the Primary Health Care Center and 39% think that the
distance to the Primary Health Care Center is far or very far.
The summary satisfaction score was 3.77 pOints and the
mean satisfaction with the services provided by physicians
was 2.56 points out of a maximum of 5 points The highest
satisfaction was for discussing psychological aspects of
patients' problems (2.96 points) and the lowest was for
attentive listening to patients' complaints (2.22 points).
PhYSicians' communication skills were more satisfactory to
patients than their professional skills and satisfying patients'
wishes scored the lowest satisfaction- Unskilled laborers,
literate patients and patients with higher income showed
significantly higher mean satisfaction while students,
illiterates, those aged less than 50 years and patients with
income less than 6000 Riyals per months scored the lowes
Non-proportional hazard rate modeling (NHRM) thr concept of NHRM
No full textIncorporating the explanatory variables into the PHRM was based on the reliability function by considering.
The application of this model will be presented on the CWD and Weibull distributions. For estimating the unknown parameters we use the maximum likelihood function
Evaluation of Heavy Metal Pollution in the Arabian Gulf Using the Clam Meretrix meretrix Linnaeus, 1758
No full textThe present study is an attempt to assess the heavy metal contamination in the marine environment of the Arabian Gulf of Saudi Arabia. The concentrations of heavy metals in water and the soft tissues of the bivalve species Meretrix meretrix Linnaeus, 1758, from different stations along the Arabian Gulf coastline, were determined during the summer season of 2008. Bioaccumulation of some heavy metals (Cd, Pb, Cu, and Zn) in fresh parts of the clam (M. meretrix) was measured by an atomic absorption spectrophotometer. The average concentrations of heavy metals in the clam tissues were 0.224–0.908, 0.294–2.496, 3.528–8.196, and 12.864–24.56 mg/kg wet weight for Cd, Pb, Cu, and Zn, respectively. In water, the mean concentration values of these metals were arranged in the following
descending order: Pb > Cu > Zn > Cd. The heavy metal concentrations in tissues of M. meretrix were within the acceptable standards set by the US Environmental Protection Agency, the Commission Européenne, and the Food and Drug Administration of the USA. From the human public health point of view, these results seem to show no possibility of acute toxicities of Cd, Cu, Pb, and Zn if the edible clam is consumed. It is recommended that relevant authorities should carry out a continual assessment on the levels of these pollutants in the studied area
Fluidization of nano-powders: Effect of sound vibration and pre-mixing with group A particles
No full textThe use of sound vibration as well as mixing of particles is investigated in this paper for improving the fluidizability of nano-powders. Amorphous anhydrous silicon dioxide, Aerosil 200, widely used in paint and pharmaceutical industries, was fluidized with air at superficial gas velocities as high as 25. cm/s. In the first part of the study, the bed was subjected to sound at 125. dB at a frequency 200. Hz. In the second part, a carefully selected additive material of the Geldart group A classification, presently sand, was added to the bed in relatively small proportions of 3, 6 and 11. wt.%. For the in situ monitoring of the fluidization dynamics, pressure fluctuations were acquired at a sampling frequency of 200. Hz using a fast-response sensitive-pressure transducer along the test section of the column located 11. cm and 23. cm above the distributor. The data thus obtained were analyzed in both time and frequency domains, and used for the reconstruction of system attractors and the determination of its principal eigenvalues. The combination of quantitative tools and digital images of the bed showed that both sound vibration and particle mixing improved the fluidization. The sound-assisted fluidization resulted in the de-agglomeration of the nano-powder, resulting in an expansion of the bed that was reflected in smaller values of the average pressure-drop. The fluidization was characterized by a strong periodic behavior. The addition of small proportions of group A powder, on the other hand, initially increased the average pressure-drop due to the concomitant rise in the bulk density, and led to a bubbling-like behavior reflected in more turbulent and less periodic fluidization. While the widely used sound-assisted fluidization exhibited a limited range of bed operation owing to the high elutriation rates of the bed material, not much limitation was observed for the case of particle mixing. This study showed that the use of appropriate small proportions of inert group A particles may be advantageous in improving the fluidization of nano-powders compared to the use of the energy intensive sound vibration.
Multi-objective optimization strategy based on desirability functions used for electrophoratic separation and quantification of rosiglitazone and glimepiride in plasma and formulations.
No full textMultiple response simultaneous optimization employing Derringer's desirability function was used for the development of a capillary electrophoresis method for the simultaneous determination of rosiglitazone (RSG) and glimepiride (GLM) in plasma and formulations. Twenty experiments, taking the two resolutions, the analysis time, and the capillary current as the responses with three important factors-buffer morality, volte and column temperature-were used to design mathematical models. The experimental responses were fitted into a second order polynomial and the six responses were simultaneously optimized to predict the optimum conditions for the effective separation of the studied compounds. The separation was carried out by using capillary zone electrophoresis (CZE) with a silica capillary column and diode array detector at 210 nm. The optimum assay conditions were 52 mmol l(-1) phosphate buffer, pH 7, and voltage of 22 kV at 29 °C. The method showed good agreement between the experimental data and predictive value throughout the studied parameter space. The assay limit of detection was 0.02 µgml(-1) and the effective working range at relative standard deviation (RSD) of ≤ 5% was 0.05-16 µgml(-1) (r = 0.999) for both drugs. Analytical recoveries of the studied drugs from spiked plasma were 97.2-101.9 ± 0.31-3.0%. The precision of the assay was satisfactory; RSD was 1.07 and 1.14 for intra- and inter-assay precision, respectively. The proposed method has a great value in routine analysis of RSG and GLM for its therapeutic monitoring and pharmacokinetic studies
Comparative study of itraconazole-cyclodextrin inclusion complex and its commercial product.
No full textItraconazole (ITZ) solid complex using hydroxypropyl-beta-cyclodextrin (ITZ-HP-beta-CD) with 20% polyvinylpyrrolidone was prepared by a co-evaporation method. The complex improved antifungal activity against C. parapasilosis and C. albicans. The complex demonstrated good flow and compressibility characteristics. The complex was formulated as a capsule dosage form and drug release was evaluated. Capsules containing ITZ-HP-beta-CD at a molar ratio of 1:3 with 20% polyvinylpyrrolidone have a faster dissolution rate than commercial capsules (Sporanox). About 88% of ITZ was released in less than 30 min and the initial dissolution rate exhibited a 3.5-fold increase compared to the commercial product. UV spectrophotometeric, HPLC, and antimicrobial methods were used to determine ITZ concentration in the release medium and the results obtained by these methods are reported. It was found that HPLC analysis is a suitable and reliable method for determination of the drug concentration with a coefficient of variation less than 10%. The intraday precision showed a coefficient of variation less than 3.96%, and that for interday was less than 4.99%. The HPLC method was more accurate and precise than the antimicrobial and UV-spectrophotometric methods for determination of ITZ concentration present in the release medium.
DOI: 10.1007/s12272-010-0706-
Pragmatic and Comparative Approach of Boundary Recognition in Wireless Sensor Networks
No full textWSN is a network which has a large number of sensor nodes; these nodes are scattered in a geometric region and communicating with each other directly. One of the demanding problems in WSNs is how to define boundary of sensor networks by identifying nodes located at edge of network. We are interested in special category of solution, node Self Detection Scheme where each node can decide for itself if it is boundary or inner node. For promising clarification, we simulate the schemes and analyse the performance in terms of error percentage and energy consumption. In this paper, such two boundary recognition algorithms named Co-operative Neighbours Scheme & New Self Detection scheme are being simulated and compared at various average degree nodes which closely found that error difference and energy consumption are relatively lesser in New Self Detection Scheme.King Saud Universit