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Mechanical properties of soil-based sustainable mycelium-bound composites
No full textAmidst the worrying growth of climate change, and the construction industry having one of the most significant adverse impacts on the environment, this calls for a need in change to this industry. Given the detrimental climate impact, the industry is increasingly shifting its focus to sustainable building material. The advancements of mycelium-based composites in building materials have shown promising results in solving this issue, due to their thermal and soundproofing properties. However, their relatively low mechanical strength remains a key limitation, warranting further research.
The objective of this study includes cultivation of mycelium in soil, a material that is less explored, preparation of ink for 3D printing of mycelium infused soil composite, optimisation of mycelium strain growth in soil and the assessment of mechanical properties of the mycelium soil composite.
The study oversees the comparative analysis of different soil composites percentage that affects the growth of mycelium, the state and type of mycelium used in the soil composites, and its mechanical properties for the different mycelium strains used.
The findings highlight Ganoderma Lucidum agar plug demonstrates better growth in soil and has higher compression strength (0.87-1.4) MPa compared to Pleurotus Ostreatus (0.28- 0.87) MPa. Additionally, 3D printing with mycelium-infused soil ink was achieved successfully using Ganoderma Lucidum, with improved growth rates observed when inoculation was applied both within and on the surface of the ink.
The success of mycelium growth with suitable strains like Ganoderma lucidum demonstrated the potential of soil as a viable substrate for cultivating mycelium-based composites. The formulation of a printable ink further opens pathways for sustainable, bio-fabricated construction materials that allows for printing of complex structures without excess material wastage. While challenges remain in upscaling and further enhancement of mechanical performance, this study lays foundational groundwork for future development of structurally improved mycelium-soil composites in sustainable architecture and construction.Bachelor's degre
Excitation-mode-selective emission through multiexcitonic states in a double perovskite single crystal.
No full textLow-dimensional lead-free metal halide perovskites are highly attractive for cutting-edge optoelectronic applications. Herein, we report a class of scandium-based double perovskite crystals comprising antimony dopants that can generate multiexcitonic emissions in the ultraviolet, blue, and yellow spectral regions. Owing to the zero-dimensional nature of the crystal lattice that minimizes energy crosstalk, different excitonic states in the crystals can be selectively excited by ultraviolet light, X-ray irradiation, and mechanical action, enabling dynamic control of steady/transient-state spectral features by modulating the excitation modes. Remarkably, the transparent crystal exhibits highly efficient white photoluminescence (quantum yield >97%), X-ray excited blue emission with long afterglow (duration >9 h), and high-brightness self-reproducible violet-blue mechanoluminescence. These findings reveal the exceptional capability of low-dimensional perovskite crystals for integrating various excitonic luminescence, offering exciting opportunities for multi-level data encryption and all-in-one authentication technologies.Published versionThis work was supported by the National Natural Science Foundation of China (Nos. 12474402 and 12004093), the Hong Kong Innovation and Technology Commission through an Innovation and Technology Fund (MHP/038/22), the Central Government to Guide Local Scientific and Technological Development (236Z1013G), Hebei Province Optoelectronic Information Materials Laboratory Performance Subsidy Fund Project (No.22567634H)
Drones over the strait: how Taiwan's UAV programme is redrawing cross-strait red lines
No full textTaiwan’s rapidly expanding drone programme – anchored by government funding, led by its defence research institute NCSIST, and strengthened by collaboration with US partners – is transforming the island’s defence posture. Unmanned systems are now central to its asymmetric strategy against an increasingly assertive China.Published versio
Android apps development for video processing
No full textThis project focuses on the development of an innovative Android application designed for video processing, tailored for smartphones and tablets. The app enables users to preview a live feed from the device's built-in camera, capture short video clips, and apply a range of editing features to enhance their content. Key functionalities include real-time video effects, filters, and basic editing tools, empowering users to create engaging videos with ease. Once edited, users can seamlessly save or share their creations across popular social media platforms such as WhatsApp, WeChat, Telegram, Instagram, and Facebook. Utilising the Android SDK and Eclipse IDE for development, this project emphasises hands-on experience by testing the app on actual devices. The outcome aims to enrich user experiences in video content creation and sharing, bridging the gap between technology and creativity.Bachelor's degre
Design and simulation of ultra high energy efficiency radio for wearable and implant biomedical applications
No full textThis paper focus on the ultra-high energy efficiency Radio Frequency (RF) receiver system design and simulation specially aimed at low-power biomedical applications. The receiver architecture incorporates all the key blocks such as Low Noise Amplifier (LNA), Bandpass Filter (BPF), Mixer, Variable Gain Amplifier (VGA) and Low Pass Filter (LPF). Each block is thoroughly designed to optimize the gain, reduce the noise figure and provide sufficient impedance matching to guarantee overall system performance. MATLAB simulations and Advanced Design System (ADS) are used to analyse and confirm the performance characteristics of the system. This would ensure that the design meets the stringent requirements of biomedical signal processing.Bachelor's degre
Equipment-level simulation of a microgrid testbed in a VR environment
No full textMicrogrids are crucial for enhancing the energy reliability and security but require extensive training due to their complexity and associated hazards. Virtual Reality (VR) offers a safe, portable, flexible and repeatable training solution, making it an ideal tool for addressing these challenges. This report outlines the development and evaluation of a VR training simulator, designed to ensure the safe operation of Nanyang Technological University’s Clean Energy Research Laboratory (NTU-CERL) microgrid testbed. This testbed is used by students and researchers at the facility for the purpose of learning and research. Building upon previous work, this project aims to enhance the effectiveness of the existing VR microgrid simulation by transitioning from a 360-camera model to a 3-dimensional (3D) point cloud model. This new model allows users to navigate freely within the environment. This is done through LiDAR scans and CAD modelling to capture the layout of the microgrid. Unity3D’s XR Origin Package was utilised to develop the simulation’s user interface features. The simulation consists of several key subsystems, including the industrial load, synchronous generator, and photovoltaic systems, packaged into a Windows build for ease of accessibility and deployment. The effectiveness of the VR simulation was then evaluated by conducting a survey on students with no prior knowledge of the microgrid’s operations. The results of the survey suggested that the simulation provides a major opportunity for users to familiarise their actions in the operation of the microgrid without the need for expert supervision. Future work could focus on the expansion of the simulation to include additional subsystems or even extending its application to other laboratory equipment for users to hone their skills, with the hopes of accelerating learning, research and innovation in this field.Bachelor's degre
Diffusing winding gradients (DWG): a parallel and scalable method for 3D reconstruction from unoriented point clouds
No full textThis article presents Diffusing Winding Gradients (DWG) for reconstructing watertight surfaces from unoriented point clouds. Our method exploits the alignment between the gradients of the screened generalized winding number (GWN) field—a robust variant of the standard GWN field—and globally consistent normals to orient points. Starting with an unoriented point cloud, DWG initially assigns a random normal to each point. It computes the corresponding screened GWN field and extracts a level set whose iso-value is the average of GWN values across all input points. The gradients of this level set are then utilized to update the point normals. This cycle of recomputing the screened GWN field and updating point normals is repeated until the screened GWN level sets stabilize and their gradients cease to change. Unlike conventional methods, DWG does not rely on solving linear systems or optimizing objective functions, which simplifies its implementation and enhances its suitability for efficient parallel execution. Experimental results demonstrate that DWG significantly outperforms existing methods in terms of runtime performance. For large-scale models with 10 to 20 million points, our CUDA implementation on an NVIDIA GTX 4090 GPU achieves speeds 30 to 120 times faster than iPSR, the leading sequential method, tested on a high-end PC with an Intel i9 CPU. Furthermore, by employing a screened variant of GWN, DWG demonstrates enhanced robustness against noise and outliers and proves effective for models with thin structures and real-world inputs with overlapping and misaligned scans. For source code and additional results, visit our project webpage: https://dwgtech.github.io/.Agency for Science, Technology and Research (A*STAR)Ministry of Education (MOE)Published versionThis work was supported in part by the Ministry of Education, Singapore, under its Academic Research Fund Grants (MOE-T2EP20220-0005 & RT19/22) and the RIE2020 Industry Alignment Fund–Industry Collaboration Projects (IAF-ICP) Funding Initiative, as well as cash and in-kind contribution from the industry partner(s). The BNU authors were supported by the Beijing Municipal Science and Technology Commission and Zhongguancun Science Park Management Committee (No. Z221100002722020), the National Nature Science Foundation of China (No. 62072045, No. 61972041), and the Nature Science Foundation of Beijing (No. 7242167). The CAS authors were supported by the Basic and Major Research Projects of ISCAS (ISCAS-JCMS-202303 and ISCAS-ZD-202401)
The earth remembers what we don't
No full textWrapped in flesh and bones, who are we but a remembrance of the life we lived? The present ‘us’ paints a silent image of our past experiences. Just like the marks etched onto surfaces of mountains and valleys, memories left behind by years of waves and winds, our memories shape the people we become.
Experiences long passed hold its own certain truth. Yet memories are a curious thing, like how the constant weathering of rocks changes its shape— they remain intangible and malleable. They shift and change with time, sometimes becoming more vivid or distorted than the actual events, with us changing alongside these memories, constantly malleable. Like vessels made from flesh and bones folding and unfolding in the hands of a potter.
"the earth remembers what we don’t" explores the formation of memories and their persistence in the world around us. Through the documentation of moulding clay, an act of mark-making on a malleable material found in various folktales and religious texts as the beginning of human life itself, the artist invites viewers to contemplate on the concept of memory retention and its immaterial form as vessels shaped by nature.Bachelor's degre
Revenue forecast valence, measurement of carbon-reduction goal, and net-zero commitment
No full textI experimentally examine whether and how the effect of management revenue forecasts on investors’ investment willingness is moderated by climate goals. Specifically, I test the joint effect of the revenue forecast valence (positive vs. negative), the carbon-reduction goal measurement (absolute vs. intensity), and the net-zero commitment (presence vs. absence). In Experiment 1, I observe that (i) the positive impact of positive versus negative revenue valence on investors’ investment willingness is reduced when the carbon-reduction goal is measured using an absolute unit than an intensity unit, and (ii) this moderating effect of carbon-reduction goal measurement is stronger when the firm discloses a net-zero commitment than when it does not. Supplementary Experiments 2a-2c test the associated causal chain. My findings contribute to the literature on revenue forecasts, carbon measurement, and climate goals and offer insights for regulators and practitioners.Doctor of Philosoph
Obstacle avoidance for A 7-DOF robot manipulator via a learning method
No full textThis dissertation explores the application of Group Relative Policy Optimization (GRPO), a novel deep reinforcement learning algorithm, for obstacle avoidance in a 7-degree-of-freedom (7-DoF) robot manipulator. Unlike Proximal Policy Optimization (PPO), GRPO eliminates the critic model and estimates the advantage based on sampled rewards from the current policy. Originally developed for natural language processing, GRPO is applied in this study to robotic control to evaluate its feasibility and effectiveness. A comparative analysis between GRPO and PPO is conducted in a simulated environment with static obstacles using MuJoCo and Gymnasium. The results demonstrate that GRPO significantly outperforms PPO in terms of convergence speed and success rate, indicating its potential for more efficient obstacle avoidance in robotic applications. However, certain limitations remain, particularly in handling dynamic obstacles and real-world uncertainties.Master's degre