Identification of Software Bugs by Analyzing Natural Language-Based Requirements Using Optimized Deep Learning Features

© 2024 Tech Science Press. All rights reserved. This is an open access article distributed under the Creative Commons Attribution License, to view a copy of the license, see: https://creativecommons.org/licenses/by/4.0/Software project outcomes heavily depend on natural language requirements, often causing diverse interpretations and issues like ambiguities and incomplete or faulty requirements. Researchers are exploring machine learning to predict software bugs, but a more precise and general approach is needed. Accurate bug prediction is crucial for software evolution and user training, prompting an investigation into deep and ensemble learning methods. However, these studies are not generalized and efficient when extended to other datasets. Therefore, this paper proposed a hybrid approach combining multiple techniques to explore their effectiveness on bug identification problems. The methods involved feature selection, which is used to reduce the dimensionality and redundancy of features and select only the relevant ones; transfer learning is used to train and test the model on different datasets to analyze how much of the learning is passed to other datasets, and ensemble method is utilized to explore the increase in performance upon combining multiple classifiers in a model. Four National Aeronautics and Space Administration (NASA) and four Promise datasets are used in the study, showing an increase in the model’s performance by providing better Area Under the Receiver Operating Characteristic Curve (AUC-ROC) values when different classifiers were combined. It reveals that using an amalgam of techniques such as those used in this study, feature selection, transfer learning, and ensemble methods prove helpful in optimizing the software bug prediction models and providing high-performing, useful end mode.Peer reviewe

Impact of reclaimed asphalt pavements on pavement sustainability

Highway pavements are one of the main building blocks of the United States infrastructure and economy. Asphalt concrete is the most common material to construct highway pavements. Billions of dollars are spent every year to maintain and rehabilitate two-million-mile the U.S. highway network. Asphalt pavement recycling is one of the few ways to reduce the amount of dollars spent on maintenance and new pavements construction. Reclaimed asphalt pavements (RAP), being a source of aggregates and asphalt binder, is the most recycled material in the U.S. However, incorporating high amount of RAP in asphalt mixtures can pose significant mix design issue and could compromise the pavement performance. Technical complications aside, for RAP to be considered a sustainable material, it is essential for it to be cost effective and socially and environmentally beneficial. The main objective of this study is to evaluate the feasibility of using high RAP in base-course asphalt mixtures. A holistic approach is taken to achieve the objective of the study; mixtures with high RAP contents are not only designed and characterized, their economic and environmental impacts have also been evaluated. The asphalt mixtures with high RAP content (up to 50%) are designed with desired and similar volumetrics as those of asphalt mixtures prepared with virgin materials, setting a great precedent for any future study conducted on high RAP content. The effect of RAP content as well as the effect of binder-grade bumping on the laboratory performance of asphalt mixtures was evaluated. Results showed that the asphalt mixtures with RAP can perform equal to the mixtures produced with virgin aggregate provided they are designed properly. The asphalt binder-grade bumping is found effective in helping to retain the original properties of the virgin mixture. An in-depth multiaxial viscoelastic characterization of the recycled mixtures is conducted by implementing a novel analytical approach. The new approach bypasses the controversial viscoelastic Poisson’s ratios and measures Young’s, shear, and bulk moduli directly in time domain. It has been shown that incorrect assumption of constant PRs for viscoelastic materials can lead to significant errors in estimating the moduli values. Use of Poisson’s ratios should be completely avoided in characterizing the asphalt concrete. The outcome of life cycle cost analysis (LCCA) and life-cycle assessment (LCA) conducted in this study showed viability of using high RAP content in asphalt mixtures. Significant reduction in cost as well as in energy consumption and global warming potential (GWP) have been observed. The economic and environmental LCA conducted under various performance scenarios highlighted the importance of achieving equivalent field performance for recycled mixtures to that of the virgin mixtures. The actual field performance of these mixtures would eventually dictate their net benefits over the virgin mixtures

Determination of Usable Residual Asphalt Binder in RAP

For current recycled mix designs, the Illinois Department of Transportation (IDOT) assumes 100% contribution of working binder from Recycled Asphalt Pavement (RAP) materials when added to Hot Mix Asphalt (HMA). However, it is unclear if this assumption is correct and whether some binder may potentially be acting as ???black rock,??? and not participating in the blending process with the new binder. Furthermore, it is also unclear whether binder modifications should be considered in the mix design for recycled HMA. The goal of this research was to determine if the current IDOT mix design practice required modification with respect to the use of RAP. A set of mixtures was prepared using RAP in accordance with current practice. Additional sets were prepared using recovered binder and recovered aggregate to simulate the effect of RAP binder blending with virgin binder. Mixes containing 0, 20, and 40%RAP were prepared and the dynamic modulus testing results of these mixtures were compared to illustrate the effect of RAP on HMA. Tests on recovered, virgin, and blended binders were also conducted using the Dynamic Shear rheometer (DSR). This study found that up to 20% RAP in HMA does not require a change in binder grade. However, at 40% RAP in HMA, a binder grade bump at high temperature and possibly at low temperature is needed; more tests are required to verify the need for low temperature binder grade bumping. In addition, this study recommends RAP fractionation in the preparation of laboratory specimens.ICT-R27-11published or submitted for publicationis peer reviewe

Energy-Aware Scalable Reliable and Void-Hole Mitigation Routing for Sparsely Deployed Underwater Acoustic Networks

In wireless underwater sensor networks (WUSNs), network protocols for information routing are usually designed when a significant number of nodes are present in the network. Therefore, for sparse conditions, when a noticeable reduction in the number of nodes occurs, the performance of such protocols exhibits a degraded behavior pattern. To cope with routing issues when sparse conditions prevail, two routing algorithms for WUSNs are proposed in this paper. They are energy-aware scalable reliable and void-hole mitigation routing (ESRVR) and cooperative energy-aware scalable reliable and void-hole mitigation routing (Co-ESRVR). The ESRVR uses a number of strategies. Firstly, it uses two hop neighbors’ information to develop routing trajectories for information advancement, as one hop information cannot avoid a void-hole, a condition when a node is not able to find neighbors towards the sea surface, and more than two hop information is difficult to obtain when sparse conditions prevail. Secondly, when a void-hole still exists, the protocol uses a backward transmission mechanism to find other routing paths to deliver packets to the end target. Thirdly, the time by which a packet is held by a node prior to transmission is short for the nodes with low energy, depth and high count of neighbors. This reduces packets loss and avoids congestion of the channel. It also helps the nodes with no or few neighbors to hold the packet for a significant chunk of time until they find suitable neighbors, due to sea tides and currents, for further packets’ advancement. The Co-ESRVR further adds reliability to information advancement by adding routing in a cooperative fashion to ESRVR, which involves packets advancement to destination along two paths: directly from source and via a relayed path. This provides multiple paths for data advancement to the sea surface, so that if one path is badly affected by the harsh sea characteristics, others may not be. Unlike the counterpart protocol, the proposed algorithms are not dependent on a node’s geographical location or the distance from the sea surface, which increases their scalability and reduces the computational complexity. Performance analysis displays superior behavior patterns of the proposed algorithms over the counterpart in terms of the compared characteristics

Impact of High RAP Contents on Structural and Performance Properties of Asphalt Mixtures

Currently, highway agencies in Illinois are exploring the feasibility of using of higher amounts of reclaimed asphalt pavement (RAP) in asphalt mixtures. Concerns about variability in aggregate gradation and higher stiffness of aged RAP binder have limited this use, however. This research project was designed to characterize the performance of hot-mix asphalt (HMA) with high amounts of RAP and to identify any special considerations that must be met to utilize these higher RAP contents. Two material sources from two districts were used to prepare eight 3/4-in nominal maximum aggregate size (NMAS) N90 binder mix designs. The mix designs included a control mix with 0% RAP and three HMAs with 30%, 40%, and 50% RAP for each district. A base asphalt binder (PG 64-22) was used in the mix design process; a single-bumped binder (PG 58-22) and a double-bumped binder (PG 58-28) were also used to prepare specimens for performance testing. The tests conducted on the HMAs were moisture susceptibility, flow number, complex modulus, beam fatigue, semi-circular bending, and wheel tracking. All tested HMAs with RAP performed equal to or better than the mixtures prepared with virgin aggregate. The study found that HMAs with high RAP content (up to 50%) can be designed with desired volumetrics. RAP fractionation proved to be very effective. Asphalt binder-grade bumping is vital for HMAs with 30% RAP content and above.Illinois Department of Transportation ICT R27-37published or submitted for publicationnot peer reviewe