National University of Computer and Emerging Sciences

About: National University of Computer and Emerging Sciences is a education organization based out in Islamabad, Pakistan. It is known for research contribution in the topics: Computer science & The Internet. The organization has 1506 authors who have published 2438 publications receiving 26786 citations.

Prediction of Microbial Spoilage and Shelf-Life of Bakery Products Through Hyperspectral Imaging

Abstract: The shelf life of bakery products highly depends on the environment and it may get spoiled earlier than its expiry which results in food-borne diseases and may affect human health or may get wasted beforehand. The traditional spoilage detection methods are time-consuming and destructive in nature due to the time taken to get microbiological results. To the best of the author’s knowledge, this work presents a novel method to automatically predict the microbial spoilage and detect its spatial location in baked items using Hyperspectral Imaging (HSI) range from $395-1000\,\,nm$ . A spectral preserve fusion technique has been proposed to spatially enhance the HSI images while preserving the spectral information. Furthermore, to automatically detect the spoilage, Principal Component Analysis (PCA) followed by K-means and SVM has been used. The proposed approach can detect the spoilage almost 24 hours before it started appearing or visible to a naked eye with 98.13% accuracy on test data. Furthermore, the trained model has been validated through external dataset and detected the spoilage almost a day before it started appearing visually.

Dark-energy cosmological models in f(G) gravity

Abstract: We discuss dark-energy cosmological models in f(G) gravity. For this purpose, a locally rotationally symmetric Bianchi type I cosmological model is considered. First, exact solutions with a well-known form of the f(G) model are explored. One general solution is discussed using a power-law f(G) gravity model and physical quantities are calculated. In particular, Kasner’s universe is recovered and the corresponding f(G) gravity models are reported. Second, the energy conditions for the model under consideration are discussed using graphical analysis. It is concluded that solutions with f(G) = G 5/6 support expansion of universe while those with f(G) = G 1/2 do not favor the current expansion.

Detecting data tampering attacks in synchrophasor networks using time hopping

Abstract: Phasor Measurement Units (PMUs) and Wide Area Measurement Systems (WAMS) have emerged as the enabling technologies for the real time monitoring, control, and operation of future smart grids. However, this cyber-infrastructure is vulnerable to a wide range of cyber security threats. Among these, one of the major threats is data tampering or data modification attacks. In these attacks, the adversary can modify/change the data of PMU packets to cause significant damage to the grid's operation and equipment. To address this problem, this paper presents a method for detecting data tampering in synchrophasor networks. The proposed protocol uses a random time hopping sequence to detect data tampering. The PMU and phasor data concentrator (PDC) share a secret seed to generate a random time hopping sequence, while a hash value of the packets combined with a secret key is used to validate the integrity of PMU packets. Security analysis of the proposed protocol shows that it can detect data tampering attacks such as data modification, data injection, and replay attacks. Our performance analysis shows that the scheme has the efficiency and robustness required for real time applications in a smart grid.