Search

Your search keyword '"Aljabri, Malak"' showing total 32 results
Start Over Author "Aljabri, Malak"
32 results on '"Aljabri, Malak"'

5. GUMSMP : a scalable parallel Haskell implementation

Author

Aljabri, Malak Saleh

Subjects
005.13, QA75 Electronic computers. Computer science
Abstract

The most widely available high performance platforms today are hierarchical, with shared memory leaves, e.g. clusters of multi-cores, or NUMA with multiple regions. The Glasgow Haskell Compiler (GHC) provides a number of parallel Haskell implementations targeting different parallel architectures. In particular, GHC-SMP supports shared memory architectures, and GHC-GUM supports distributed memory machines. Both implementations use different, but related, runtime system (RTS) mechanisms and achieve good performance. A specialised RTS for the ubiquitous hierarchical architectures is lacking. This thesis presents the design, implementation, and evaluation of a new parallel Haskell RTS, GUMSMP, that combines shared and distributed memory mechanisms to exploit hierarchical architectures more effectively. The design evaluates a variety of design choices and aims to efficiently combine scalable distributed memory parallelism, using a virtual shared heap over a hierarchical architecture, with low-overhead shared memory parallelism on shared memory nodes. Key design objectives in realising this system are to prefer local work, and to exploit mostly passive load distribution with pre-fetching. Systematic performance evaluation shows that the automatic hierarchical load distribution policies must be carefully tuned to obtain good performance. We investigate the impact of several policies including work pre-fetching, favouring inter-node work distribution, and spark segregation with different export and select policies. We present the performance results for GUMSMP, demonstrating good scalability for a set of benchmarks on up to 300 cores. Moreover, our policies provide performance improvements of up to a factor of 1.5 compared to GHC- GUM. The thesis provides a performance evaluation of distributed and shared heap implementations of parallel Haskell on a state-of-the-art physical shared memory NUMA machine. The evaluation exposes bottlenecks in memory management, which limit scalability beyond 25 cores. We demonstrate that GUMSMP, that combines both distributed and shared heap abstractions, consistently outper- forms the shared memory GHC-SMP on seven benchmarks by a factor of 3.3 on average. Specifically, we show that the best results are obtained when shar- ing memory only within a single NUMA region, and using distributed memory system abstractions across the regions.

Published
2015

8. Balancing Shared and Distributed Heaps on NUMA Architectures

Author

Aljabri, Malak, Loidl, Hans-Wolfgang, Trinder, Phil, Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Doug, Series editor, Weikum, Gerhard, Series editor, Hage, Jurriaan, editor, and McCarthy, Jay, editor

Published
2015
Full Text
View/download PDF

21. AI-Based Techniques for Ad Click Fraud Detection and Prevention: Review and Research Directions.

Author

Alzahrani, Reem A. and Aljabri, Malak

Subjects
FRAUD investigation, ARTIFICIAL intelligence, FRAUD, TRAFFIC surveys
Abstract

Online advertising is a marketing approach that uses numerous online channels to target potential customers for businesses, brands, and organizations. One of the most serious threats in today's marketing industry is the widespread attack known as click fraud. Traffic statistics for online advertisements are artificially inflated in click fraud. Typical pay-per-click advertisements charge a fee for each click, assuming that a potential customer was drawn to the ad. Click fraud attackers create the illusion that a significant number of possible customers have clicked on an advertiser's link by an automated script, a computer program, or a human. Nevertheless, advertisers are unlikely to profit from these clicks. Fraudulent clicks may be involved to boost the revenues of an ad hosting site or to spoil an advertiser's budget. Several notable attempts to detect and prevent this form of fraud have been undertaken. This study examined all methods developed and published in the previous 10 years that primarily used artificial intelligence (AI), including machine learning (ML) and deep learning (DL), for the detection and prevention of click fraud. Features that served as input to train models for classifying ad clicks as benign or fraudulent, as well as those that were deemed obvious and with critical evidence of click fraud, were identified, and investigated. Corresponding insights and recommendations regarding click fraud detection using AI approaches were provided. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

27. An Assessment of Lexical, Network, and Content-Based Features for Detecting Malicious URLs Using Machine Learning and Deep Learning Models.

Author

Aljabri, Malak, Alhaidari, Fahd, Mohammad, Rami Mustafa A., Samiha Mirza, Alhamed, Dina H., Altamimi, Hanan S., and Chrouf, Sara Mhd. Bachar

Subjects
*MACHINE learning, *DEEP learning, *UNIFORM Resource Locators, *WORLD Wide Web, *FEATURE selection, *WEB services
Abstract

The World Wide Web services are essential in our daily lives and are available to communities through Uniform Resource Locator (URL). Attackers utilize such means of communication and create malicious URLs to conduct fraudulent activities and deceive others by creating deceptive and misleading websites and domains. Such threats open the doors for many critical attacks such as spams, spyware, phishing, and malware. Therefore, detecting malicious URL is crucially important to prevent the occurrence of many cybercriminal activities. In this study, we examined a set of machine learning (ML) and deep learning (DL) models to detect malicious websites using a dataset comprising 66,506 records of URLs. We engineered three different types of features including lexical-based, network-based and content-based features. To extract the most discriminative features in the dataset, we applied several features selection algorithms, namely, correlation analysis, Analysis of Variance (ANOVA), and chi-square. Finally, we conducted a comparative performance evaluation for several ML and DL models considering set of criteria commonly used to evaluate such models. Results depicted that Naïve Bayes (NB) was the best model for detecting malicious URLs using the applied data with an accuracy of 96%. This research has made contribution to the field by conducting significant features engineering and analysis to identify the best features for malicious URLs predictions, compare different models and achieve a high accuracy using a large new URL dataset. [ABSTRACT FROM AUTHOR]

Published
2022
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results