QuSecNets: Quantization-based Defense Mechanism for Securing Deep Neural Network against Adversarial Attacks

Adversarial examples have emerged as a significant threat to machine learning algorithms, especially to the convolutional neural networks (CNNs). In this paper, we propose two quantization-based defense mechanisms, Constant Quantization (CQ) and Trainable Quantization (TQ), to increase the robustness of CNNs against adversarial examples. CQ quantizes input pixel intensities based on a "fixed" number of quantization levels, while in TQ, the quantization levels are "iteratively learned during the training phase", thereby providing a stronger defense mechanism. We apply the proposed techniques on undefended CNNs against different state-of-the-art adversarial attacks from the open-source \textit{Cleverhans} library. The experimental results demonstrate 50%-96% and 10%-50% increase in the classification accuracy of the perturbed images generated from the MNIST and the CIFAR-10 datasets, respectively, on commonly used CNN (Conv2D(64, 8x8) - Conv2D(128, 6x6) - Conv2D(128, 5x5) - Dense(10) - Softmax()) available in \textit{Cleverhans} library

Synthesis and characterization of a novel series of benzenesulfonylurea and thiourea derivatives of 2H-pyran and 2H-pyridine-2-ones as antibacterial, antimycobacterial and antifungal agents

Arylhydrazines reacted with dehydroacetic acid (1) to give the corresponding 2H-pyran-2-one hydrazones (2), which on treatment with hydrazine hydrate afforded the corresponding 1-amino-2H-pyridin-2-ones (3). Reaction of 3 with nitrous acid, aromatic aldehyde and substituted benzenesulfonyl chlorides yielded the corresponding 2H-pyridine-2-one derivatives. A series of urea and thiourea derivatives were also prepared. Some of these compounds have shown significant antibacterial and mild to moderate antimycobacterial and antifungal activities

Preparation, Characterization and Antimicrobial Activity Study of Some Transition Metal Complexes of 4-Flourophenyl -4-Nitrobenzylidene

A new Schiff base of 4- flourophenyl-4- nitrobenzyliden (L) ,was prepared and used to prepare a number of metal complexes with Cr (III) , Fe (III), Co(II) ,Ni (II) and Cu (II). These complexes were isolated and characterized by (FITR),UV-Vis spectroscopy and flame atomic absorption techniques in addition to magnetic susceptibility, and conductivity measurements. The study of the nature of the complexes formed in ethanol was done following the molar ratio method gave results, agreed with those obtained from isolated solid state studies. The antibacterial activity for the ligand and its metal complexes were examined against two selected microorganisms, Pseudomonas aeruginosa and Staphylococcus aureus.The results indicated that the complexes show the enhanced activity in comparison to the free ligand; these were attributed to the synergetic effect between the metal ion and the ligand in addition to the difference in the structural varieties

A Comparative Study for enhancing PV Penetration limit of a LV CIGRE Residential Network with Distributed Grid-Tie Single-Phase PV Systems

Photovoltaic distributed generation (PVDG) has seen tremendous growth in recent years, especially in the residential sector. Among other concerns, the voltage rise in AC networks is considered the most limiting factor in achieving increased PV penetration levels. A steady-state impact study is performed on a CIGRE low-voltage (LV) residential network. This paper compares six techniques to increase the PV penetration limit in the LV residential network, namely single-phase penetration (SPP), Distribution Scheme 1 (DS1), Distribution Scheme 2 (DS2), alternate phase penetration (APP), offline tap adjustment (OTA) and switched on-load tap adjustment (SOLTA). PSCAD software is used for this study. The best results are obtained for the DS2-SOLTA case that gives the minimum voltage magnitude and voltage unbalance in the system. The steady-state results are validated by a dynamic data study using measured solar irradiance and residential load data. A novel approach is also proposed for calculating the worst day from the data set. The obtained results verify the effectiveness of the proposed approach

A Novel Features-Based Multivariate Gaussian Distribution Method for the Fraudulent Consumers Detection in the Power Utilities of Developing Countries

According to statistics, developing countries all over the world have suffered significant non-technical losses (NTLs) both in natural gas and electricity distribution. NTLs are thought of as energy that is consumed but not billed e.g., theft, meter tampering, meter reversing, etc. The adaptation of smart metering technology has enabled much of the developed world to significantly reduce their NTLs. Also, the recent advancements in machine learning and data analytics have enabled a further reduction in these losses. However, these solutions are not directly applicable to developing countries because of their infrastructure and manual data collection. This paper proposes a tailored solution based on machine learning to mitigate NTLs in developing countries. The proposed method is based on a multivariate Gaussian distribution framework to identify fraudulent consumers. It integrates novel features like social class stratification and the weather profile of an area. Thus, achieving a significant improvement in fraudulent consumer detection. This study has been done on a real dataset of consumers provided by the local power distribution companies that have been cross-validated by onsite inspection. The obtained results successfully identify fraudulent consumers with a maximum success rate of 75%. 2013 IEEE.This work was supported by the Qatar National Library.Scopus2-s2.0-8510734936

Two-stage PCR assay for detection of human brucellosis in endemic areas

BACKGROUND: Brucellosis is a common zoonosis that can cause a severe febrile illness in humans. It constitutes a persistent health problem in many developing countries around the world. It is one of the most frequently reported diseases in Saudi Arabia and incidence is particularly high in the Central region, and around the city of Riyadh. The aim of this study was to evaluate a two-stage PCR assay for detection of human brucellosis particularly in endemic areas. METHODS: A total of 101 serum samples were collected from patients with acute febrile illness (AFI) of unknown cause from two different locations in the Western region of Saudi Arabia. The first location (Northern) is characterized by a nomadic rural population while the second (Central) is a modern urban city. All samples were subjected to DNA extraction and Brucella genus-specific PCR amplification using B4/B5 primers of the bcsp31 gene. Positive B4/B5 samples were subjected to multiplex species-specific Brucella PCR amplification. RESULTS: In the Northern location, 81.9% of the AFI samples were confirmed Brucella positive, while all the samples collected from the Central region proved to be Brucella negative. Samples positive for Brucella were subjected to multiplex species-specific Brucella amplification. B. abortus was detected in 10% and B. melitensis in 8% of the samples, while the majority (82%) of samples showed both B. abortus and B. melitensis. As expected, B. suis was not detected in any of the samples. CONCLUSIONS: This study concluded that a two-stage PCR assay could be useful as a rapid diagnostic tool to allow the consideration of brucellosis as a possible cause of AFI, particularly in non-urban locations. It also recommends the collection of epidemiological data for such patients to obtain further information that may help in rapid diagnosis

4-[5-(Furan-2-yl)-3-trifluoro­methyl-1H-pyrazol-1-yl]benzene­sulfonamide

In the title compound, C14H10F3N3O3S, there are significant twists in the mol­ecule, as seen in the values of the dihedral angles between the pyrazole ring and each of the furan [31.1 (2)°] and benzene rings [55.58 (10)°]. The amino N atom occupies a position almost normal to the benzene ring [N—S—Car—Car (ar = aromatic) torsion angle = 83.70 (19)°]. One amino H atom forms a hydrogen bond to the tricoordinate pyrazole N atom and the other inter­acts with a sulfonamide O atom, forming a supra­molecular chain along [010]. The chains are consolidated into a supra­molecular layers via C—H⋯O inter­actions involving the second sulfonamide O atom; layers stack along [10-1]. The furan ring was found to be disordered over two diagonally opposite orientations of equal occupancy