Semantics-based Automated Web Testing

We present TAO, a software testing tool performing automated test and oracle generation based on a semantic approach. TAO entangles grammar-based test generation with automated semantics evaluation using a denotational semantics framework. We show how TAO can be incorporated with the Selenium automation tool for automated web testing, and how TAO can be further extended to support automated delta debugging, where a failing web test script can be systematically reduced based on grammar-directed strategies. A real-life parking website is adopted throughout the paper to demonstrate the effectivity of our semantics-based web testing approach.Comment: In Proceedings WWV 2015, arXiv:1508.0338

Enhanced spin injection efficiency in a four-terminal double quantum dot system

Within the scheme of quantum rate equations, we investigate the spin-resolved transport through a double quantum dot system with four ferromagnetic terminals. It is found that the injection efficiency of spin-polarized electrons can be significantly improved compared with single dot case. When the magnetization in one of four ferromagnetic terminals is antiparallel with the other three, the polarization rate of the current through one dot can be greatly enhanced, accompanied by the drastic decrease of the current polarization rate through the other one. The mechanism is the exchange interaction between electrons in the two quantum dots, which can be a promising candidate for the improvement of the spin injection efficiency.Comment: 10 pages and 5 figure

Extracting ππ\pi\pi SS-wave scattering lengths from cusp effect in heavy quarkonium dipion transitions

Charge-exchange rescattering $\pi^+\pi^-\to \pi^0\pi^0$ leads to a cusp effect in the $\pi^0\pi^0$ invariant mass spectrum of processes with $\pi^0\pi^0$ in the final state which can be used to measure $\pi\pi$ $S$-wave scattering lengths. Employing a non-relativistic effective field theory, we discuss the possibility of extracting the scattering lengths in heavy quarkonium $\pi^0\pi^0$ transitions. The transition $\Upsilon(3S)\to\Upsilon(2S)\pi^0\pi^0$ is studied in details. We discuss the precision that can be reached in such an extraction for a certain number of events.Comment: 15 pages, 7 figures, 1 tabl

Genetic Algorithm Based Approach for Nucleic Acid Pattern Extraction

Finding a common pattern among nucleic acid sequences in a given database is an important yet relatively difficult problem in computational biology. Such a pattern is useful for describing the characteristics of a certain family of nucleic acid sequences, and can also be used for classification purposes as well as examine the closeness of two organisms. In this paper, we present a global pattern extraction tool named GAPE which can be applicable in computational biology to describe a certain family of nucleic acid sequences with common features. The algorithm utilizes an optimized Genetic Algorithm (GA) framework to drive the evolution of desirable patterns. A specialized pair-wise alignment algorithm is also introduced to efficiently examine the closeness of a sequence to a regular expression pattern. Experimental results using real biological data are shown to indicate the effectiveness of the tool

Selective attachment of benzonitrile on Si(111)-7×7: Configuration, selectivity, and mechanism

The cycloaddition of benzonitrile with Si(111)-7×7 has been investigated as a model system for understanding the interaction of conjugated π-electron systems with Si(111)-7×7 using high-resolution electron energy loss spectroscopy, x-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy, scanning-tunneling microscopy (STM), and density-functional-theory calculation (perturbative Beck-Perdew functional in conjugation with a basis set of DN**). Vibrational features of chemisorbed benzonitrile unambiguously demonstrate that the cyano group directly interacts with Si surface dangling bonds, evidenced in the disappearance of C≡N stretching mode around 2256 cm-1 coupled with the appearance of C=N stretching mode at 1623 cm-1 and the retention of all vibrational signatures of phenyl ring. XPS shows that both C 1s and N 1s core levels of the cyano groups display large down-shifts by 2.5 and 1.5 eV, respectively, after chemisorption. A smaller down-shift of ∼0.8 eV is observed for the C 1s core level of phenyl group due to the weaker inductive effect of the formed C=N groups in chemisorbed benzonitrile than that of C≡N groups in physisorbed molecules. Compared with physisorbed molecules, the photoemission from πCN orbitals of chemisorbed benzonitrile is significantly reduced, suggesting the direct involvement of πCN in the surface binding. These experimental results show that the covalent attachment of benzonitrile on Si(111)-7×7 occurs in a selective manner through the (2+2) cycloaddition between the cyano group and the adjacent adatom-rest atom pair. The cycloadduct formed contains an intact phenyl ring protruding into vacuum, retaining aromaticity. This functionalized Si surface may serve as a substrate for further modification or act as an intermediate for fabrication of multilayer organic thin films or materials syntheses in vacuum

Top quark decays with flavor violation in the B-LSSM

The decays of top quark $t\rightarrow c\gamma,\;t\rightarrow cg,\;t\rightarrow cZ,\;t\rightarrow ch$ are extremely rare processes in the standard model (SM). The predictions on the corresponding branching ratios in the SM are too small to be detected in the future, hence any measurable signal for the processes at the LHC is a smoking gun for new physics. In the extension of minimal supersymmetric standard model with an additional local $U(1)_{B-L}$ gauge symmetry (B-LSSM), new gauge interaction and new flavor changing interaction affect the theoretical evaluations on corresponding branching ratios of those processes. In this work, we analyze those processes in the B-LSSM, under a minimal flavor violating assumption for the soft breaking terms. Considering the constraints from updated experimental data, the numerical results imply $Br(t\rightarrow c\gamma)\sim5\times10^{-7}$, $Br(t\rightarrow cg)\sim2\times10^{-6}$, $Br(t\rightarrow cZ)\sim4\times10^{-7}$ and $Br(t\rightarrow ch)\sim3\times10^{-9}$ in our chosen parameter space. Simultaneously, new gauge coupling constants $g_{_B},\;g_{_{YB}}$ in the B-LSSM can also affect the numerical results of $Br(t\rightarrow c\gamma,\;cg,\;cZ,\;ch)$.Comment: 20 pages, 4 figures, published in EPJC. arXiv admin note: substantial text overlap with arXiv:1803.0990