Heavy Color-Octet Particles at the LHC

Many new-physics models, especially those with a color-triplet top-quark partner, contain a heavy color-octet state. The "naturalness" argument for a light Higgs boson requires that the color-octet state be not much heavier than a TeV, and thus it can be pair-produced with large cross sections at high-energy hadron colliders. It may decay preferentially to a top quark plus a top-partner, which subsequently decays to a top quark plus a color-singlet state. This singlet can serve as a WIMP dark-matter candidate. Such decay chains lead to a spectacular signal of four top quarks plus missing energy. We pursue a general categorization of the color-octet states and their decay products according to their spin and gauge quantum numbers. We review the current bounds on the new states at the LHC and study the expected discovery reach at the 8-TeV and 14-TeV runs. We also present the production rates at a future 100-TeV hadron collider, where the cross sections will be many orders of magnitude greater than at the 14-TeV LHC. Furthermore, we explore the extent to which one can determine the color octet's mass, spin, and chiral couplings. Finally, we propose a test to determine whether the fermionic color octet is a Majorana particle.Comment: 20 pages, 9 figures; journal versio

Fourth Generation Leptons and Muon g−2g-2

We consider the contributions to $g_\mu-2$ from fourth generation heavy neutral and charged leptons, $N$ and $E$, at the one-loop level. Diagrammatically, there are two types of contributions: boson-boson-$N$, and $E$-$E$-boson in the loop diagram. In general, the effect from $N$ is suppressed by off-diagonal lepton mixing matrix elements. For $E$, we consider flavor changing neutral couplings arising from various New Physics models, which are stringently constrained by $\mu\to e\gamma$. We assess how the existence of a fourth generation would affect these New Physics models.Comment: Minor changes, with references update

Speech Dereverberation Based on Integrated Deep and Ensemble Learning Algorithm

Reverberation, which is generally caused by sound reflections from walls, ceilings, and floors, can result in severe performance degradation of acoustic applications. Due to a complicated combination of attenuation and time-delay effects, the reverberation property is difficult to characterize, and it remains a challenging task to effectively retrieve the anechoic speech signals from reverberation ones. In the present study, we proposed a novel integrated deep and ensemble learning algorithm (IDEA) for speech dereverberation. The IDEA consists of offline and online phases. In the offline phase, we train multiple dereverberation models, each aiming to precisely dereverb speech signals in a particular acoustic environment; then a unified fusion function is estimated that aims to integrate the information of multiple dereverberation models. In the online phase, an input utterance is first processed by each of the dereverberation models. The outputs of all models are integrated accordingly to generate the final anechoic signal. We evaluated the IDEA on designed acoustic environments, including both matched and mismatched conditions of the training and testing data. Experimental results confirm that the proposed IDEA outperforms single deep-neural-network-based dereverberation model with the same model architecture and training data

Mobile game for the elderly: Bundled Bingo Game

The aim of this project is to develop a customized Bingo game based on the user interface guidelines that suit the elderly users. This project targeted to improve the cognitive ability of the elderly with the specifically designed gaming features. In this research, qualitative data will be used to analyze the confidence and acceptance level of the elderly on the mobile digital games, as well as to understand how the elderly interacts with current technologies (mobile devices) and the benefit they can gain from the mobile games. User testing, survey, and result analysis have been done with a group of elderly members from D’Happy club in Petaling Jaya, Malaysia. The results of this project contribute to the development of an elderly friendly mobile game to motivate the elderly’s engagement in mobile gaming, with the will that it could help to delay and decrease the risk of the elderly in developing the Alzheimer’s disease

Experimental and Theoretical Studies on Formability of 22MnB5 at Elevated Temperatures by Gleeble Simulator

AbstractThis paper, which includes an experimental analysis and theoretical predictions, presents a method to investigate the formability of high strength steel sheet 22MnB5 at elevated temperatures. In this method, two designs for tensile test specimens with laser engraving grids are developed and used to obtain the strain paths of a uniaxial tensile state and the plane strain occurring at elevated temperatures using a Gleeble simulator. On the other hand, a modified Cockcroft criterion that takes strain path into consideration is employed to predict the entire forming limit diagram. A forming limit diagram could be established as a result of using the modified Cockcroft criterion together with the limit strains obtained from the tensile tests based on two novel specimen designs. In this paper, forming limit diagrams at three strain rates and forming limit diagrams at temperatures ranging from 650 oC to 850 oC were established