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Performance bugs challenge software development, degrading performance and wasting computational resources. Software developers invest substantial effort in addressing these issues. Curating these performance bugs can offer valuable insights to the software engineering research community, aiding in developing new mitigation strategies. However, there is no large-scale open-source performance bugs dataset available. To bridge this gap, we propose PerfCurator, a repository miner that collects performance bug-related commits at scale. PerfCurator employs PcBERT-KD, a 125M parameter BERT model trained to classify performance bug-related commits. Our evaluation shows PcBERT-KD achieves accuracy comparable to 7 billion parameter LLMs but with significantly lower computational overhead, enabling cost-effective deployment on CPU clusters. Utilizing PcBERT-KD as the core component, we deployed PerfCurator on a 50-node CPU cluster to mine GitHub repositories. This extensive mining operation resulted in the construction of a large-scale dataset comprising 114K performance bug-fix commits in Python, 217.9K in C++, and 76.6K in Java. Our results demonstrate that this large-scale dataset significantly enhances the effectiveness of data-driven performance bug detection systems.

Smart devices are considered as an integral part of Internet of Things (IoT), have an aim to make a dynamic network to exchange information, collect data, analysis, and make optimal decisions in an autonomous way to achieve more efficient, automatic, and economical services. Message dissemination among these smart devices allows adding new features, sending updated instructions, alerts or safety messages, informing the pricing information or billing amount, incentives, and installing security patches. On one hand, such message disseminations are directly beneficial to the all parties involved in the IoT system. On the other hand, due to remote procedure, smart devices, vendors, and other involved authorities might have to meet a number of security, privacy, and performance related concerns while disseminating messages among targeted devices. To this end, in this paper, we design STarEdgeChain, a security and privacy aware targeted message dissemination in IoT to show how blockchain along with advanced cryptographic techniques are devoted to address such concerns. In fact, the STarEdgeChain employs a permissioned blockchain assisted edge computing in order to expedite a single signcrypted message dissemination among targeted groups of devices, at the same time avoiding the dependency of utilizing multiple unicasting approaches. Finally, we develop a software prototype of STarEdgeChain and show it's practicability for smart devices. The codes are publicly available at https://github.com/mbaqer/Blockchain-IoT, Comment: 12 pages

The properties of rotating neutron stars are investigated using eight equations of state (EOSs). We also study the relations between various observables corresponding to different angular velocities for all those EOSs. All of these EoSs lead to non-rotating compact stars with maximum masses between 1.8 to 2.25 $M_{\odot}$. We calculate the moment of inertia and studied its variation with mass and the relation between central energy density and angular momentum. We compare our results with the observational findings from the most massive pulsar PSR J0740+6620 and the heaviest secondary component in the black hole - neutron star merger GW190814. It is noted that the secondary compact object of GW190814 having mass $\sim 2.6 M_{\odot}$ might be explained as a rapidly rotating neutron star (NS) with frequency larger than 1000 Hz., Comment: 8 pages, 8 figures, 4 tables

In previous studies [1, 2, 3] the possible existence dark matter admixed pulsar have been discussed based on three different dark matter density profiles, Singular Isothermal Sphere density profile, Universal Rotational Curve density profile and Navarro-Frenk-White density profile. They have been used to discuss the pulsars present in our Milky Way galaxy as well as some satellite dwarf galaxies of Milky Way. In this article we use the Universal Rotational Curve (URC) dark matter density profile to observe similar effects on galaxies M31 and M87. These study hold significant importance, as now it can be concluded that there is a fair possibility of presence of dark matter admixed pulser in M31 and M87 galaxies as well., Comment: 17 pages, 16 figures, 2 tables

In the context of this paper, microlenses present as oblate clusters of dark matter structures called massive astrophysical compact halo object(MACHO) in the galactic halo are considered. The NFW density profile [1] is derived from the observational data and works best in the halo region of the exterior part of the galaxy. Hence this profile is used to plot the potential, deflection angle, and critical and caustic curves for the aforementioned microlenses using numerical methods. Moreover, this model is compared with an older density profile model [2], and the differences in their caustic and critical curves are pointed out. This leads to the conclusion that the NFW model produces caustic and critical curves that occupy a smaller region than portrayed by the caustic and critical curves produced by the older density profile model. However, the differences are not that significant to these structures act as microlenses as they are so small and beyond the scope of modern telescopes, and thus only the light curves can be detected from these structures., Comment: 15 pages, 7 figures, 1 table

In this paper we attempt to construct a regular gravastar model using the UV corrected framework of Loop Quantum Cosmology. We find that a stable gravastar model can be constructed with a number of unique features: (i) no thin shell approximation needs to be invoked to obtain solutions in the shell which can be considered to be of a finite thickness, (ii) the central singularity of a self gravitating object can be averted by a bounce mechanism, such that the interior density of the gravastar reaches a maximum critical density and cannot be raised further due to an operative repulsive force, (iii) the inherent isotropy of the effective fluid description does not prevent the formation of a stable gravastar and anisotropic pressures is not an essential requirement., Comment: 15 pages, 11 figures

Event-by-event particle ratio fluctuations for simulated data sets of three different models named UrQMD, AMPT, and Pythia are studied using the fluctuation variable $\nu_{dyn}$. The simulated data sets produced in $pp$ collisions at four different LHC energies $\sqrt{s} = 2.76, 5.02, 7$ and $13$ TeV are generated and considered for this analysis. The variation of fluctuation parameter $\nu_{dyn}$ for accepted pair of meson and baryon combination $i.e.$ $[\pi, K]$, $[\pi, p]$ and $[p, K]$ with the increasing value of the mean multiplicity of charged particles ($\langle N_{ch} \rangle$) are investigated. It has been observed that the correlation between the particle pair $[\pi, K]$ is more than that of the two other particle pairs $[\pi, p]$ and $[p, K]$. However, the energy-wise inspection of the fluctuation variable $\nu_{dyn}$ for $0-10\%$ centrality data shows the increase in the correlation between the particles in each pair for all three models considered., Comment: 16 pages, 18 figures, Submitted to Journal for peer-review

In this paper, we construct a traversable static Lorentzian wormhole in the effective scenario of Loop Quantum Cosmology (LQC), where the field equations are modified due to the ultraviolet (UV) corrections introduced at large space-time curvatures. A stable wormhole can be constructed in the effective scenario without the violation of Null energy condition (NEC) by physical matter at the throat. The NEC is effectively violated due to the corrections in the field equations from LQC, resolving the Weyl curvature singularity at the throat. However, the physical matter does violate the Strong energy condition (SEC), suggesting the interesting possibility that dark energy can be harnessed into a wormhole. A possible explanation for this is the presence of inherent pressure isotropy in the UV-corrected field equations (discussed and compared to braneworld wormholes in the discussion). No additional exotic ingredient (violating NEC) is required, avoiding quantum instabilities. The tidal forces at the throat do not diverge and also the throat is found to be stable. The wormhole features an attractive geometry. LQC can resolve both types of curvature singularities appearing at the black hole center and wormhole throat, without exotic matter., Comment: 10 Pages, 4 Figures

Submitting fake certificates is a common problem in Southeast Asia, which prevents qualified candidates from getting the jobs they deserve. When applying for a job, students must provide academic credentials as proof of their qualifications, acquired both inside and outside the classroom. Verifying academic documents before hiring is crucial to prevent fraud. Employing blockchain technology has the potential to address this issue. Blockchain provides an electronic certificate that is tamper-proof and non-repudiable, making it difficult for students to manipulate their academic credentials. This paper presents a prototype for an academic credential verification model that leverages the security features of blockchain and IPFS (Interplanetary File System). Certificates are temporarily stored in a database before being transferred to IPFS, where a unique hash code is generated using a hashing algorithm. This hash code serves as the certificate's unique identity and is stored in the blockchain nodes. Companies can verify an applicant's credentials by searching for the applicant and accessing their already verified certificates. Utilizing IPFS as a middleman storage platform lowers the expenses of directly storing massive data on the blockchain. To sum it up, the proposed solution would make the process of certificate verification more efficient, secure, and cost-effective. It would save time and resources that would otherwise be used to manually verify certificates., Comment: Presented at International Conference on. Inventive Communication and Computational Technologies 2023

In this paper we have explored the possibility of constructing a traversable wormhole on the Shtanov-Sahni braneworld with a timelike extra dimension. We find that the Weyl curvature singularity at the throat of the wormhole can be removed with physical matter satisfying the NEC $\rho+p \geq 0$, even in the absence of any effective $\Lambda$-term or any type of charge source on the brane. (The NEC is however violated by the effective matter description on the brane arising due to effects of higher dimensional gravity.) Besides satisfying NEC the matter constituting the wormhole also satisfies the Strong Energy Condition (SEC), $\rho+3p \geq 0$, leading to the interesting possibility that normal matter on the brane may be harnessed into a wormhole. Incidentally, these conditions also need to be satisfied to realize a non-singular bounce and cyclic cosmology on the brane\cite{Sahni4} where both past and future singularities can be averted. Thus, such a cyclic universe on the brane, constituted of normal matter can naturally contain wormholes. The wormhole shape function on the brane with a time-like extra dimension represents the tubular structure of the wormhole spreading out at large radial distances much better than in wormholes constructed in a braneworld with a spacelike extra dimension and have considerably lower mass resulting in minimization of the amount of matter required to construct a wormhole. Wormholes in the Shtanov-Sahni (SS) braneworld also have sufficiently low tidal forces, facilitating traversability. Additionally they are found to be stable and exhibit a repulsive geometry. We are left with the intriguing possibilty that both types of curvature singularity can be resolved with the SS model, which we discuss at the end of the concluding section., Comment: 31 Pages, 16 Figures

In this paper, we attempt to explore the possibility of a obtaining a viable emergent universe scenario supported by a type of fluid known as the extended Chaplygin gas, which extends a modification to the equation of state of the well known modified Chaplygin gas by considering additional higher order barotropic fluid terms. We consider quadratic modification only. Such a fluid is capable of explaining the present cosmic acceleration and is a possible dark energy candidate. We construct a theoretical model of the emergent universe assuming it is constituted from such a fluid. It interestingly turns out that the theoretical constraints we obtain on the extended Chaplygin gas parameters from our emergent universe model are well in agreement with the observational constraint on these parameters from BICEP2 data. Our model is found to replicate the late time behaviour really well and reproduces $\Lambda$-CDM like behaviour, as evident from the analysis of the statefinder parameters. Moreover, the Hubble parameter analysis shows that for theoretically constrained values of the ECG parameters, the Hubble tension can be resolved yielding higher values of the present Hubble parameter $H_0$ in all possible cases. Also, the value of $H(z)$ at a redshift $z=2.34$ fits better than $\Lambda-CDM$ with recent observations in some cases. This leads us to the realization that such a fluid is not only a probable candidate for dark energy, but also sources an emergent universe unlike modified Chaplygin gas and the initial singularity problem can be resolved in a flat universe within the standard relativistic context., Comment: 16 Pages, 4 Figures

In this paper, we study the slowly rotating neutron stars in $f(R, T)$ gravity based on Hartle-Thorne formalism. We first consider the simplest matter-geometry coupled modified gravity, namely $f(R, T)=R+2\chi T$. We compute the mass, radius, moment of inertia, change in radius, and binding energy due to rotation, eccentricity, quadrupole moment, and the tidal love number. The quantities, which are of the second order in angular velocity, like change in radius and binding energy due to rotation, eccentricity, and quadrupole moment, deviate more from their corresponding general relativistic counterparts in lighter neutron stars than heavier ones. Whereas the moment of inertia, which is of the first order in angular velocity, in $f(R, T)=R+2\chi T$ modified gravity, barely diverges from the general relativistic one. The Equation of state-independent I-Love-Q relation retains in this $f(R, T) $ modified gravity, and it coincides with the general relativistic ones within less than one percent even for the maximum allowed coupling parameters. We also study the slowly rotating neutron star in $f(R, T)=R+\alpha R^{2}+2\chi T$ up to first order their angular velocity. We calculate the mass, radius, and moment of inertia of neutron stars in this modified gravity. The results show that the impact of the matter-geometric coupling parameter is greater on lighter neutron stars in both of these modified gravity models.