Modal analysis of a cable-stayed bridge model using a modified Ibrahim Time domain algorithm

Modal analysis procedures are efficient techniques to identify modal properties of structures. The objective of this work is to conduct a vibration survey of a laboratory cable-stayed bridge model and to develop a systematic method for the extraction of the dynamic characteristics of the bridge model. The proposed method is based on the classical Ibrahim Time Domain (ITD) method and allows directly use the real time acceleration response measured from accelerometers due to ambient excitations. This is a clear advantage over classical ITD method. The feasibility and practicality are examined through a numerical study and an ambient modal testing of the bridge model. The modified method provides a very effective way to identify the dynamical properties of the structure. Modal analysis results shows that the bridge model is characterized by the presence of many closely spaced, coupled modes

The Swift X-ray Telescope Cluster Survey III: Cluster Catalog from 2005-2012 Archival Data

We present the Swift X-ray Cluster Survey (SWXCS) catalog obtained using archival data from the X-ray telescope (XRT) on board the Swift satellite acquired from 2005 to 2012, extending the first release of the SWXCS. The catalog provides positions, soft fluxes, and, when possible, optical counterparts for a flux-limited sample of X-ray group and cluster candidates. We consider the fields with Galactic latitude |b| > 20 degree to avoid high HI column densities. We discard all of the observations targeted at groups or clusters of galaxies, as well as particular extragalactic fields not suitable to search for faint extended sources. We finally select ~3000 useful fields covering a total solid angle of ~400 degree^2. We identify extended source candidates in the soft-band (0.5-2keV) images of these fields using the software EXSdetect, which is specifically calibrated for the XRT data. Extensive simulations are used to evaluate contamination and completeness as a function of the source signal, allowing us to minimize the number of spurious detections and to robustly assess the selection function. Our catalog includes 263 candidate galaxy clusters and groups down to a flux limit of 7E-15 erg/cm^2/s in the soft band, and the logN-logS is in very good agreement with previous deep X-ray surveys. The final list of sources is cross-correlated with published optical, X-ray, and SZ catalogs of clusters. We find that 137 sources have been previously identified as clusters, while 126 are new detections. Currently, we have collected redshift information for 158 sources (60% of the entire sample). Once the optical follow-up and the X-ray spectral analysis of the sources are complete, the SWXCS will provide a large and well-defined catalog of groups and clusters of galaxies to perform statistical studies of cluster properties and tests of cosmological models.Comment: 41 pages, 16 figures, 3 tables, published on ApJS in Jan 201

Arduino-based Gamification Tool for Multipurpose Usage in Teaching and Learning at Rural Schools.

The purpose of the project is to develop an Arduino-based gamification tool for multipurpose usage in teaching and learning at rural schools. In fact, rural schools that do not receive fair share of education funding directly lead to lack of basic infrastructure, no clean water supply and no 24-hour electricity supply. Thus, student in rural school eventually do not have chances to access to latest technologies to aid in learning. With the problem statement, the objective for the project is to develop a gamification prototype system using Arduino to learn physic STEM topics, develop an interactive interface to facilitate student’s learning in the topics and also create a low energy mini-projector/OHP as a solution to electricity deficient areas. Gamification through education is one of the great innovative technique that used to improve quality of education. Gamification is a way uses game thinking and game mechanic in a non-game context to engage user’s involvement. Gamification in education will motivate student in learning process and improve classroom interaction and engagement. This gamified prototype is developed using Arduino which acts as mini projector and also an overhead projector. Hence, student in rural schools able to learn STEM physic subject in Light reflection and refr interactive way. The prototype is tested at semi rural schools Sarawak and the feedback collected from the teachers and students is good and met expectations

Task Specific Humanoid Hand Design using Single Crystal Ultrasonic Motors

Master'sMASTER OF ENGINEERIN

Cooperative Multi-Objective Reinforcement Learning for Traffic Signal Control and Carbon Emission Reduction

Existing traffic signal control systems rely on oversimplified rule-based methods, and even RL-based methods are often suboptimal and unstable. To address this, we propose a cooperative multi-objective architecture called Multi-Objective Multi-Agent Deep Deterministic Policy Gradient (MOMA-DDPG), which estimates multiple reward terms for traffic signal control optimization using age-decaying weights. Our approach involves two types of agents: one focuses on optimizing local traffic at each intersection, while the other aims to optimize global traffic throughput. We evaluate our method using real-world traffic data collected from an Asian country's traffic cameras. Despite the inclusion of a global agent, our solution remains decentralized as this agent is no longer necessary during the inference stage. Our results demonstrate the effectiveness of MOMA-DDPG, outperforming state-of-the-art methods across all performance metrics. Additionally, our proposed system minimizes both waiting time and carbon emissions. Notably, this paper is the first to link carbon emissions and global agents in traffic signal control.Comment: arXiv admin note: substantial text overlap with arXiv:2205.1129