Bounded Verification of Multi-threaded Programs via Lazy Sequentialization

Bounded verification techniques such as bounded model checking (BMC) have successfully been used for many practical program analysis problems, but concurrency still poses a challenge. Here, we describe a new approach to BMC of sequentially consistent imperative programs that use POSIX threads. We first translate the multi-threaded program into a nondeterministic sequential program that preserves reachability for all round-robin schedules with a given bound on the number of rounds. We then reuse existing high-performance BMC tools as backends for the sequential verification problem. Our translation is carefully designed to introduce very small memory overheads and very few sources of nondeterminism, so it produces tight SAT/SMT formulae, and is thus very effective in practice: Our Lazy-CSeq tool implementing this translation for the C programming language won several gold and silver medals in the concurrency category of the Software Verification Competitions (SV-COMP) 2014–2021 and was able to find errors in programs where all other techniques (including testing) failed. In this article, we give a detailed description of our translation and prove its correctness, sketch its implementation using the CSeq framework, and report on a detailed evaluation and comparison of our approach.

An Evaluation Study of e-Learning Course at the Duhok Polytechnic University A Case Study

In last decade, there has been a growing awareness in E-Learning which is the most recent type of distance education, and becomes a highly significant model of educational technology. Today e-Learning studies indicate that there is an increasing use of this educational scheme for students, trainers and instructors which improve the learning capability of the students and trainee by depending on student-centered learning (SCL) scheme rather than using the traditional teacher or trainer centered teaching mechanism.However, students’ awareness for the advantage of using e-Learning has not been significantly investigated, especially in Iraq. The aim of this article is to inspect students’ awareness of the using of e-Learning at the Dohuk Polytechnic University. Participants involved in this study were 100 students studying the C++ programming language course during 2015-2016 and 2017-2018 academic years and 210 students studying computer application course during 2018-2019.

An Evaluation Study of an E-Learning Course at the Duhok Polytechnic University

In last decade, there has been a growing awareness in E-Learning which is the most recent type of distance education, and becomes a highly significant model of educational technology. Today e-Learning studies indicate that there is an increasing use of this educational scheme for students, trainers and instructors which improve the learning capability of the students and trainee by depending on student-centered learning (SCL) scheme rather than using the traditional teacher or trainer centered teaching mechanism.However, students’ awareness for the advantage of using e-Learning has not been significantly investigated, especially in Iraq. The aim of this article is to inspect students’ awareness of the using of e-Learning at the Dohuk Polytechnic University. Participants involved in this study were 100 students studying the C++ programming language course during 2015-2016 and 2017-2018 academic years and 210 students studying computer application course during 2018-2019.

SPI: Automated Identification of Security Patches via Commits

Security patches in open source software, providing security fixes to identified vulnerabilities, are crucial in protecting against cyber attacks. Security advisories and announcements are often publicly released to inform the users about potential security vulnerability. Despite the National Vulnerability Database (NVD) publishes identified vulnerabilities, a vast majority of vulnerabilities and their corresponding security patches remain beyond public exposure, e.g., in the open source libraries that are heavily relied on by developers. As many of these patches exist in open sourced projects, the problem of curating and gathering security patches can be difficult due to their hidden nature. An extensive and complete security patches dataset could help end-users such as security companies, e.g., building a security knowledge base, or researcher, e.g., aiding in vulnerability research. To efficiently curate security patches including undisclosed patches at large scale and low cost, we propose a deep neural-network-based approach built upon commits of open source repositories. First, we design and build security patch datasets that include 38,291 security-related commits and 1,045 Common Vulnerabilities and Exposures (CVE) patches from four large-scale C programming language libraries. We manually verify each commit, among the 38,291 security-related commits, to determine if they are security related. We devise and implement a deep learning-based security patch identification system that consists of two composite neural networks: one commit-message neural network that utilizes pretrained word representations learned from our commits dataset and one code-revision neural network that takes code before revision and after revision and learns the distinction on the statement level. Our system leverages the power of the two networks for Security Patch Identification. Evaluation results show that our system significantly outperforms SVM and K-fold stacking algorithms. The result on the combined dataset achieves as high as 87.93% F1-score and precision of 86.24%. We deployed our pipeline and learned model in an industrial production environment to evaluate the generalization ability of our approach. The industrial dataset consists of 298,917 commits from 410 new libraries that range from a wide functionalities. Our experiment results and observation on the industrial dataset proved that our approach can identify security patches effectively among open sourced projects.

Theories on the Formation and Evolution of Black Holes & Galaxies

Conventional theory suggests that black holes are singularities of enormous mass-density: matter compressed beyond imagination due to extreme mass-based gravitational forces and possessing so much mass-based gravity that light itself cannot escape them. As an alternative to convention, this paper builds on the theories of fire-tornado accretion cylinder vortex forces and colossal magnetic pressure spawned within (previously described by the authors in their paper on ~2D planar celestial kinematics), and analyzes them in more detail specifically for black holes and the formation / evolution of galaxies. Several interesting charge-distribution and associated electromagnetic field components will be utilized in the modeling. To demonstrate concept, the proposed forces during formation and evolution will be computationally modeled and translated into visual simulations in 4-D space-time using C# programming in the Unity operating platform.

Toward a More Robust Home Automated System

The work reported in this article developed a home automated system using voice activation. This is with a view to providing users complete control over electrical appliances using simple easy to remember voice commands on an Android mobile device. This work was implemented using the Atmega 328 microcontroller, Relays and a Wi-Fi shield. The human voice is first converted to text using a Natural language processing tool from the Android based application. Thereafter, the text is sent over the internet via the PubNub to the microcontroller. The Atmega 328 microcontroller was programmed on an Arduino using C programming language and the Android based application was developed using Android Software Development Kit. Results obtained from the testing show that the implemented system achieves the mean scores of 8, 7.6, and 7.2 for ease of use, learnability and effectiveness respectively justifying the fact that the system is capable of controlling appliances by changing their state (ON/OFF) from remote a location with a response time within the reasonable limit.

An analysis of the possibility of realization steganography in C#

The computing power of modern computers is sufficient to break many cryptographic keys, therefore it is necessary to create an additional security layer which hides the very fact of transmitting a secret message. For this purpose, steganographic methods can be used. The article is devoted to the analysis of the possibility of implementing digital images steganography with the use of the C # programming language. Firstly, existing libraries and mathematical transformations which can help with performing steganography were found. Also, own code solutions were implemented. In order to objectively evaluate the methods of data hiding, the parameters describing the degree of distortion of transforms and hidden images were calculated. Subsequently, optimal solutions for specific problems were identified and demonstrational data hiding was performed. Based on the obtained results, it can be concluded that it is possible to successfully implement steganography in the C # language. There are many ready-made libraries and tools, the effectiveness of which has been verified in the conducted analysis. Due to the contradictory of stenographic requirements, it is not possible to meet all of them optimally, i.e. undetectability, resistance to destruction and information capacity. For this reason, it is not possible to clearly indicate the best solutions. In order to achieve satisfactory results, one should look for compromises between the set requirements.