Particle production and apparent decoherence due to an accelerated time-delay

We study the radiation produced by an accelerated time-delay acting on the left moving modes. Through analysis via the Schrodinger picture, we find that the final state is a two-mode squeezed state of the left moving Unruh modes, implying particle production. We analyse the system from an operational point of view via the use of self-homodyne detection with broad-band inertial detectors. We obtain semi-analytical solutions that show that the radiation appears decohered when such an inertial observer analyses the information of the radiation from the accelerated time-delay source. We make connection with the case of the accelerated mirror. We investigate the operational conditions under which the signal observed by the inertial observer can be purified.Comment: 19 pages, 13 figure

Modeling key drivers of e-learning satisfaction among student teachers

This study explored the key drivers of student teachers' e-learning satisfaction. Three hundred and eighty-seven participants completed a survey questionnaire measuring their self-reported responses to six constructs (tutor quality, perceived usefulness, perceived ease of use, course delivery, facilitating conditions, and course satisfaction). Data analysis was performed using structural equation modeling. The results of this study showed that, apart from facilitating conditions, all constructs were significant predictors of e-learning satisfaction. However, facilitating conditions was found to be a significant mediator of perceived ease of use and satisfaction. Some implications for e-learning and teacher education were discussed

Investigating the technology acceptance among student teachers in Malaysia : an application of the Technology Acceptance Model (TAM).

This study investigated 245 Malaysian student teachers' self-reported intentions to use (ITU) computers. Using the Technology Acceptance Model (TAM) as a research framework, this study found perceived usefulness (PU) of computer technology, perceived ease of use (PEU), and attitude towards computer use (ATCU) to be significant determinants of ITU. Results obtained using structural equation modelling revealed that (I) PEU significantly influenced PU, (2) both PU and PEU significantly influenced ATCU, and (3) both PU and ATCU significantly influenced ITU. In essence, the results of this study present some evidence that TAM serves as a valid model to predict technology acceptance among student teachers in Malaysia

Permutation Routing in the Hypercube and Grid Topologies

The problem of edge disjoint path routing arises from applications in distributed memory parallel computing. We examine this problem in both the directed hypercube and two-dimensional grid topologies. Complexity results are obtained for these problems where the routing must consist entirely of shortest length paths. Additionally, approximation algorithms are presented for the case when the routing request is of a special form known as a permutation. Permutations simply require that no vertex in the graph may be used more than once as either a source or target for a routing request. Szymanski conjectured that permutations are always routable in the directed hypercube, and this remains an open problem

A Constructive Proof of Ky Fan\u27s Generalization of Tucker\u27s Lemma

We present a proof of Ky Fan\u27s combinatorial lemma on labellings of triangulated spheres that differs from earlier proofs in that it is constructive. We slightly generalize the hypotheses of Fan\u27s lemma to allow for triangulations of Sn that contain a flag of hemispheres. As a consequence, we can obtain a constructive proof of Tucker\u27s lemma that holds for a more general class of triangulations than the usual version

The Use of Multi-Scale Fiducial Markers To Aid Takeoff and Landing Navigation by Rotorcraft

This paper quantifies the impact of adverse environmental conditions on the detection of fiducial markers (i.e., artificial landmarks) by color cameras mounted on rotorcraft. We restrict our attention to square markers with a black-and-white pattern of grid cells that can be nested to allow detection at multiple scales. These markers have the potential to enhance the reliability of precision takeoff and landing at vertiports by flying vehicles in urban settings. Prior work has shown, in particular, that these markers can be detected with high precision (i.e., few false positives) and high recall (i.e., few false negatives). However, most of this prior work has been based on image sequences collected indoors with hand-held cameras. Our work is based on image sequences collected outdoors with cameras mounted on a quadrotor during semi-autonomous takeoff and landing operations under adverse environmental conditions that include variations in temperature, illumination, wind speed, humidity, visibility, and precipitation. In addition to precision and recall, performance measures include continuity, availability, robustness, resiliency, and coverage volume. We release both our dataset and the code we used for analysis to the public as open source.Comment: Extended abstract accepted at the 2024 AIAA SciTec

Universal quantum computation with optical four-component cat qubits

We propose a teleportation-based scheme to implement a universal set of quantum gates with a four-component cat code, assisted by appropriate entangled resource states and photon number resolving detection. The four-component cat code features the ability to recover from single photon loss. Here, we propose a concrete procedure to correct the single photon loss, including detecting the single photon loss event and recovering the initial states. By concatenating with standard qubit error correcting codes, we estimate the loss threshold for fault-tolerant quantum computation and obtain a significant improvement over the two-component cat code.Comment: 5+22 pages, 5 figures, comments are welcom