Bug Fix Time Optimization Using Matrix Factorization and Iterative Gale-Shaply Algorithms

Bug triage is an essential task in software maintenance phase. It assigns developers (fixers) to bug reports to fix them. This process is performed manually by a triager, who analyzes developers profiles and submitted bug reports to make suitable assignments. Bug triaging process is time consuming thus automating this process is essential to improve the quality of software. Previous work addressed triaging problem either as an information retrieval or classification problem. This paper tackles this problem as a resource allocation problem, that aims at the best assignments of developers to bug reports, that reduces the total fixing time of the newly submitted bug reports, in addition to the even distribution of bug reports over developers. In this paper, a combination of matrix factorization and Gale Shapely algorithm, supported by the differential evolution is firstly introduced to optimize the total fix time and normalize developers work load. Matrix factorization is used to establish a recommendation system for Gale-Shapley to make assignment decisions. Differential evolution provides the best set of weights to build developers score profiles. The proposed approach is assessed over three repositories, Linux, Apache and Eclipse. Experimental results show that the proposed approach reduces the bug fixing time, in comparison to the manual triage, by 80.67%, 23.61% and 60.22% over Linux, Eclipse and Apache respectively. Moreover, the workload for the developers is uniform.Comment: 14 page, 7 figures, 8 tables, 10 equation

Utilizing DNA Strands for Secured Data-Hiding with High Capacity

There are continuous threats to network technologies due to its rapidly-changing nature, which raises the demand for data-safe transmission. As a result, the need to come up with new techniques for securing data and accommodating the growing quantities of information is crucial. From nature to science, the idea that genes themselves are made of information stimulated the research in molecular deoxyribonucleic acid (DNA). DNA is capable of storing huge amounts of data, which leads to its promising effect in steganography. DNA steganography is the art of using DNA as an information carrier which achieves high data storage capacity as well as high security level. Currently, DNA steganography techniques utilize the properties of only one DNA strand, since the other strand is completely dependent on the first one. This paper presents a DNA-based steganography technique that hides data into both DNA strands with respect to the dependency between the two strands. In the proposed technique, a key of the same length of the reference DNA sequence is generated after using the second DNA strand. The sender sends both the encrypted DNA message and its reference DNA sequence together into a microdot. If the recipient receives this microdot uncontaminated, the sender can safely send the generated key afterwards. The proposed technique doubles the amount of data stored and guarantees a secure transmission process as well, for even if the attacker suspects the first-sent DNA sequence, they will never receive the key, and hence full data extraction is nearly impossible. The conducted experimental study confirms the effectiveness of the proposed

Prevalence, Clinical Criteria and Sociodemographic Predictors of Trichomonas vaginalis Infection in Suspected Egyptian Women, Using Direct Diagnostic Techniques

Background: The present study aimed to determine the prevalence and associated risk factors of vaginal trichomoniasis in women referred to gynecologic clinic in Benha University Hospital, Egypt. Methods: Two hundred female patients enrolled in the study. Vaginal samples were obtained from them and examined for T. vaginalis by wet mount, Giemsa stain, Acridine orange (AO) stain and culture on modified Diamond’s medium. For analysis of accuracy of the methods used, the receiver operating characteristic (ROC) curve concept with culture as a gold standard was applied. Results: Out of 200 patients, T. vaginalis was found in 22 (11%) patients by any of the diagnostic methods used. The accuracy of AO staining comes next to Dia­mond’s culture (AUC 0.909, sensitivity 81.8%, specificity 100%, CI 0.81-1.0) fol­lowed by Giemsa staining (AUC 0.835, sensitivity 68.2%, specificity 98.9%, CI 0.72-0.95). The wet mount was the least accurate method (AUC 0.795, sensitivity 59.1%, specificity 100%, CI 0.67-0.92). There was no significant association be­tween potentially supposed risk factors and trichomoniasis except patients complain­ing of either dysuria and dyspareunia or back pain and abdominal pain. Conclusion: Trichomoniasis is a common disease in our community. Sociodemo­graphic factors do not seem to affect the prevalence among different Egyptian population. For accurate diagnosis, laboratory investigation is essential. A positive wet smear is diagnostic, but negative samples should be examined by methods that are more sensitive