An Android Malware Detection Framework-based on Permissions and Intents

With an exponential growth in smartphone applications targeting useful services such as banks, healthcare, m-commerce, security has become a primary concern. The applications downloaded from unofficial sources pose a security threat as they lack mechanisms for validation of the applications. The malware infected applications may lead to several threats such as leaking user’s private information, enforcing malicious deductions for sending premium SMS, getting root privilege of the android system and so on. Existing anti-viruses depend on signature databases that need to be updated from time to time and are unable to detect zero-day malware. The Android Operating system allows inter-application communication through the use of component reuse by using intents. Unfortunately, message passing is also an application attack surface. A hybrid method for android malware detection by analysing the permissions and intent-filters of the manifest files of the applications is presented. A malware detection framework is developed based on machine learning algorithms and on the basis of the decision tree obtained from ID3 and J48 classifiers available in WEKA. Both algorithms gave same results with an error percentage of 6 per cent. The system improves detection of zero day malware

The association of ambient nitrogen dioxide and particulate matter exposure on infant lung function.

Doctoral Degrees. University of KwaZulu-Natal, Durban.Abstract available in PDF

Designing Secure and Survivable Stegosystems

Steganography, the art and science of carrying out hidden communication, is an emergingsub-discipline of information security. Unlike cryptography, steganography conceals the existenceof a secret message by embedding it in an innocuous container digital media, thereby enablingunobstrusive communication over insecure channels. Detection and extraction of steganographiccontents is another challenge for the information security professional and this activity iscommonly known as steganalysis. Recent progress in steganalysis has posed a challenge fordesign and development of stegosystems with high levels of security and survivability. In thispaper, different strategies have been presented that can be used to escape detection and foilan eavesdropper having high technical capabilities as well as adequate infrastructure. Based onthe strength and weaknesses of current steganographic schemes, ideas have been progressedto make detection and destruction of hidden information more difficult

A Hybrid Computational Intelligence based Technique for Automatic Cryptanalysis of Playfair Ciphers

The Playfair cipher is a symmetric key cryptosystem-based on encryption of digrams of letters. The cipher shows higher cryptanalytic complexity compared to mono-alphabetic cipher due to the use of 625 different letter-digrams in encryption instead of 26 letters from Roman alphabets. Population-based techniques like Genetic algorithm (GA) and Swarm intelligence (SI) are more suitable compared to the Brute force approach for cryptanalysis of cipher because of specific and unique structure of its Key Table. This work is an attempt to automate the process of cryptanalysis using hybrid computational intelligence. Multiple particle swarm optimization (MPSO) and GA-based hybrid technique (MPSO-GA) have been proposed and applied in solving Playfair ciphers. The authors have attempted to find the solution key applied in generating Playfair crypts by using the proposed hybrid technique to reduce the exhaustive search space. As per the computed results of the MPSO-GA technique, correct solution was obtained for the Playfair ciphers of 100 to 200 letters length. The proposed technique provided better results compared to either GA or PSO-based technique. Furthermore, the technique was also able to recover partial English text message for short Playfair ciphers of 80 to 120 characters length

A Survey of Computer Security Models

ABSTRACT A security model maps the abstract goals of the security policy of information system by specifying information flow necessary to enforce the security policy. The security model that characterize the security goal in a form, which are then mapped to system details. The security model takes the requirement and provides the necessary mathematical formulas, relationships, and structure to be followed to accomplish the security goal. This paper gives brief introduction of security model from the beginning

A review of ambient air pollution exposure assessment methods in determining childhood respiratory health effects in children under five

Various epidemiological studies have reported on air pollution exposure-related lung function decline and respiratory health effects in children. Children have increased susceptibility to ambient air pollutants as physiological and structural changes of the lung are still occurring within the first five years of life after birth. This review examines applications in air pollution exposure assessment methods when evaluating lung function and respiratory health concentration-response effects in young children, while considering the effects of critical windows of exposure. We identified 13 studies that used various methods of exposure assessment in assessing respiratory health outcomes (presence of lower respiratory tract infections, respiratory symptoms, wheezing and asthma) in children under five. The methods applied included personal monitoring (n = 1), proximity-based methods (n = 3), inverse distance weighting (n = 2), geographic weighted regression (n = 1), dispersion modeling (n = 1), satellite-based methods (n = 2) and land use regression modeling (n = 5). These studies assessed exposure and outcomes at different "windows of susceptibility": antenatally/specific trimesters (n = 8), infancy (n = 5) and early childhood (n = 6). In most studies, the reported measures of air pollutants were noted to be below the prescribed limits, though for some, a cause-effect association was observed. It was also noted that there was very little variation in estimates between time points or trimesters of exposure, likely attributed to limitations in the selected exposure assessment method. Moderate to high correlations between trimesters were reported for most studies. © 2022 by the authors

Harbor and intra-city drivers of air pollution: findings from a land use regression model, Durban, South Africa

Multiple land use regression models (LUR) were developed for different air pollutants to characterize exposure, in the Durban metropolitan area, South Africa. Based on the European Study of Cohorts for Air Pollution Effects (ESCAPE) methodology, concentrations of particulate matter (PM; 10; and PM; 2.5; ), sulphur dioxide (SO; 2; ), and nitrogen dioxide (NO; 2; ) were measured over a 1-year period, at 41 sites, with Ogawa Badges and 21 sites with PM Monitors. Sampling was undertaken in two regions of the city of Durban, South Africa, one with high levels of heavy industry as well as a harbor, and the other small-scale business activity. Air pollution concentrations showed a clear seasonal trend with higher concentrations being measured during winter (25.8, 4.2, 50.4, and 20.9 µg/m; 3; for NO; 2; , SO; 2; , PM; 10; , and PM; 2.5; , respectively) as compared to summer (10.5, 2.8, 20.5, and 8.5 µg/m; 3; for NO; 2; , SO; 2; , PM; 10; , and PM; 2.5; , respectively). Furthermore, higher levels of NO; 2; and SO; 2; were measured in south Durban as compared to north Durban as these are industrial related pollutants, while higher levels of PM were measured in north Durban as compared to south Durban and can be attributed to either traffic or domestic fuel burning. The LUR NO; 2; models for annual, summer, and winter explained 56%, 41%, and 63% of the variance with elevation, traffic, population, and Harbor being identified as important predictors. The SO; 2; models were less robust with lower R; 2; annual (37%), summer (46%), and winter (46%) with industrial and traffic variables being important predictors. The R; 2; for PM; 10; models ranged from 52% to 80% while for PM; 2.5; models this range was 61-76% with traffic, elevation, population, and urban land use type emerging as predictor variables. While these results demonstrate the influence of industrial and traffic emissions on air pollution concentrations, our study highlighted the importance of a Harbor variable, which may serve as a proxy for NO; 2; concentrations suggesting the presence of not only ship emissions, but also other sources such as heavy duty motor vehicles associated with the port activities

A New S-Box Design by Applying Bat Algorithm Based Technique

Substitution-boxes (S-boxes) are very important nonlinear components used for achieving strong confusion for enhancing cryptographic security in most of the block ciphers. Designing cryptographically strong S-boxes has been a major research domain for the designers of symmetric crypto systems. In the proposed research work, Bat Algorithm based swarm technique is proposed to design strong S-boxes.  Cryptographic strong S-boxes are obtained by the developed swarm technique. Authors analyze cryptographic strength of the obtained S-box by evaluating properties like Bijectivity, Nonlinearity, Bit-Independence Criterion, Linear Probability and Differential Uniformity. The obtained performance parameters for the designed new S-box by the swarm technique are compared with some recently reported S-boxes in the literature. The designed S-box has good cryptographic strength. The designed S-box has good cryptographic strength like nonlinearity = 110.75 and average Strict Avalanche Criterion (SAC) value = 0.506. For the constructed S-box, most of the Differential uniformity components are 4 and shows uniform distribution approximately. The proposed new S-box is also free from the fixed points

Air quality modelling in Catalonia from a combination of solar radiation, surface reflectance and elevation

Air quality in developed areas is being increasingly compromised by the effect of urbanization, which is favouring the presence of atmospheric pollutants derived from human-induced activities. Land cover change is one of the consequences most closely associated with urbanization, leading to a growing presence of dark built-up surfaces. The target of this investigation was to model the Catalonian Air Quality Index (CAQI) from the combined effect of the surface reflectance capacity of urban surfaces with solar radiation and elevation. Geoprocessing tools were used to produce the information required to characterise these variables in the buffer areas surrounding 75 different air quality monitoring stations located across the region. Cluster analysis and Multiple Linear Regression (MLR) were applied to group these stations according to their similarity and replicate the annual mean values of CAQI recorded in Catalonia in 2011, respectively. Finally, discriminant analysis enabled assigning ungauged areas to the cluster and MLR model that best fitted their solar radiation, surface reflectance and elevation features. The implementation of this approach resulted in highly accurate predictions of CAQI, providing a mechanism of identification of areas having a number of days with poor air quality during the year. Since these areas were related to the presence of land cover types with high sunlight absorption, the proposed methodology was suggested to support the adoption of measures aimed at controlling urban air pollution based on replacing built-up surfaces by green infrastructure.This paper was possible thanks to the research project SUPRIS-SUReS (Ref. BIA2015-65240-C2-1-R MINECO/FEDER, UE), financed by the Spanish Ministry of Economy and Competitiveness with funds from the State General Budget (PGE) and the European Regional Development Fund (ERDF). The authors also wish to express their gratitude to all the entities that provided the data necessary to develop this study: the Department of Statistics and the Directorate of Environmental Monitoring of the Barcelona City Council, the Cartographic and Geological Institute of the Government of Catalonia and the National Centre of Geographic Information (CNIG) of the Spanish Ministry of Public Works and Transport