Taiwan Association of Engineering and Technology Innovation: E-Journals
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A Study on the Vehicle Routing Problem Considering Infeasible Routing Based on the Improved Genetic Algorithm
Get PDFThe study aims to optimize the vehicle routing problem, considering infeasible routing, to minimize losses for the company. Firstly, a vehicle routing model with hard time windows and infeasible route constraints is established, considering both the minimization of total vehicle travel distance and the maximization of customer satisfaction. Subsequently, a Floyd-based improved genetic algorithm that incorporates local search is designed. Finally, the computational experiment demonstrates that compared with the classic genetic algorithm, the improved genetic algorithm reduced the average travel distance by 20.6% when focusing on travel distance and 18.4% when prioritizing customer satisfaction. In both scenarios, there was also a reduction of one in the average number of vehicles used. The proposed method effectively addresses the model introduced in this study, resulting in a reduction in total distance and an enhancement of customer satisfaction
Evolution of Vortex Structures Generated by a Rigid Flapping Wing with a Winglet in Quiescent Water
Get PDFThis study aims to the utilization of vortex structures generated through wing flapping for achieving sustainable flight, and the motivation is elicited by the phenomenon observed in natural flyers. The vortex structures in the flow field generated by a flapping rigid wing are captured using vorticity and the LAMDA2 criterion. The study investigates a comparative analysis between a wing both with and without a winglet. Moreover, the influence of flapping frequency is examined as well. For the experiments, particle image velocimetry (PIV) measurements are employed for the flow field around mechanical flapping motion in a quiescent water condition. The flapping mechanism has one-degree freedom, showing a 1:3 ratio in motion, and tested wings at 1.5 and 2.0 Hz. A “modified” vortex filamentation and fragmentation phenomenon is proposed as a significant finding in the present study, based on a comprehensive analysis of the flow field around the wing with a winglet
Challenges and Solutions to Criminal Liability for the Actions of Robots and AI
Get PDFCivil liability legislation is currently being developed, but little attention has been paid to the issue of criminal liability for the actions of robots. The study describes the generations of robots and points out the concerns about robots’ autonomy. The more autonomy robots obtain, the greater capacity they have for self-learning, yet the more difficulty in proving the failure foreseeability when designing and whether culpability or the elements of a specific crime can be considered. In this study, the tort liability depending on the category of robots is described, and the possible solutions are analyzed. It is shown that there is no need to introduce new criminal law constructions, but to focus on the process of proof. Instead of changing the legal system, it is necessary to create the most detailed audit trail telling about the robot’s actions and surroundings or to have a digital twin of the robot
Efficient Object Detection and Intelligent Information Display Using YOLOv4-Tiny
Get PDFThis study aims to develop an innovative image recognition and information display approach based on you only look once version 4 (YOLOv4)-tiny framework. The lightweight YOLOv4-tiny model is modified by replacing convolutional modules with Fire modules to further reduce its parameters. Performance reductions are offset by including spatial pyramid pooling, and they also improve the model’s detection ability for objects of various sizes. The pattern analysis, statistical modeling, and computational learning visual object classes (PASCAL VOC) 2012 dataset are used, the proposed modified YOLOv4-tiny architecture achieves a higher mean average precision (mAP) that is 1.59% higher than its unmodified counterpart. This study addresses the need for efficient object detection and recognition on resource-constrained devices by leveraging YOLOv4-tiny, Fire modules, and SPP to achieve accurate image recognition at a low computational cost
Comparison of FLUMEN and HEC-RAS 2D Models for Flash Flood Inundation in Urban Landscape
Get PDFFlood inundation maps play a crucial role in preventing flood damage. Among various numerical models used to generate these maps, the fluvial modeling engine (FLUMEN) and the hydrologic engineering center’s river analysis system (HEC-RAS 2D) are particularly effective for simulating urban floods, which are influenced by complex factors such as buildings and landscapes. This study aims to examine the differences in flood analysis results that may arise from using different numerical models. This study compares the performance of FLUMEN and HEC-RAS 2D in modeling urban flash floods, characterized by local velocity variations and complex geometries. The analysis focuses on their numerical characteristics and simulation accuracy. The simulation results show that HEC-RAS 2D outperforms FLUMEN in handling turbulence, numerical stability, and peak water level predictions. These findings provide insights into the strengths and limitations of each model for urban flood management
Analysis of Atomization Performance of Linear Laval Nozzle under Varied Water Pressures Based on VOF and DPM Models
Get PDFParticulate matter from coal and stone operations is a primary air pollution source. The traditional nozzle requires high-pressure conditions, and the atomization droplets are large and uneven. This paper aims to study a linear Laval nozzle and investigate the impact of water pressure on atomization performance. The volume of fluid (VOF) model and discrete phase model (DPM) of Fluent are used to simulate the internal and external fields of the nozzle and analyze the velocity, droplet size, and atomization angle. The results show that the optimized water pressure parameters are 0.1 MPa with an air pressure of 0.5 MPa. Droplets in the middle are smaller, while those on the sides are larger. Compared to traditional nozzles, the water pressure is reduced by over 90%, and the Sauter mean diameter (SMD) decreases by over 50%. Moreover, the theoretical spray angle increases by approximately 150%
Fracture Behavior of Crop Circle Ceramic Tiles: Experimental and Numerical Study
Get PDFThis research investigates the effect of three-dimensional (3D) bee-crop-circle tiles on load deformation, initial cracking and propagation, and stress redistribution. Experimental tests provide limited data due to the small specimen size and brittle nature of the material. A finite element (FE) model is constructed and validated by laboratory data to analyze the stress-strain responses and failure mode. The model enables a detailed description of stress patterns, stress propagation, and redistribution of layers beneath the bee design. The study concludes that a 3D crop circle-inspired design significantly influences the ultimate load-carrying capacity and stress-related behavior. The load-deformation response is nonlinear, and the coloring influences the thickness of coatings, further affecting the ultimate load and initial stiffness. Furthermore, designs with convex details result in an arc action, deviating the stress concentrations away from the line of loading. The FE model slightly overestimates the initial stiffness but represents the ultimate load and load-displacement response with high accuracy
Road Repair Delay Costs in Improving the Road Rehabilitation Strategy through a Comprehensive Road User Cost Model
Get PDFThis study delves into quantifying the adverse effects of road damage on users, particularly focusing on the increased travel time and consequent financial burdens stemming from delayed repairs. Utilizing a comparative method, the research underscores notable reductions in speed and prolonged travel times due to damaged roads, leading to substantial economic losses for road users. To streamline the estimation of road user costs (RUC), the study proposes a simulation model that incorporates varying traffic volumes and repair delays. This model demonstrates a high level of accuracy in estimating RUC, revealing heightened sensitivity to fluctuations in traffic volume and repair delays compared to agency costs. Consequently, the research underscores the imperative of implementing effective repair strategies to alleviate these impacts efficiently, thereby emphasizing the significance of timely infrastructure maintenance in mitigating financial burdens on road users
Leveraging 3D Printing Capability for Geopolymer Composites Based on Fly Ash with Cotton Fibers Addition
Get PDFThe study explores the use of fly ash as a base material for extrusion-based 3D printing and the impact of incorporating 1% cotton fibers on print properties. Characterization of the base material involves X-ray techniques, particle size distribution analysis, and microscopy. Mechanical properties are tested via bending and compressive strength. Meanwhile, thermal conductivity is also tested. Cotton fibers reduce print strength for loads applied perpendicularly and parallel to the printed sample layers by about 20-23% for compressive strength and 14-24% for flexural strength, possibly due to fiber agglomeration. Thermal conductivity decreases by approximately 12.17% compared to the base material. The results indicate the importance of the current study, i.e., assessing the different types of additives to enhance the mechanical and thermal properties of printed materials. Such ongoing research will facilitate the utilization of 3D printing in creating geopolymer composites
A Codebook Compression Method for Vector Quantization Algorithm
Get PDFThis study introduces a novel approach to enhance the compression ratio of the vector quantization (VQ) algorithm by specifically targeting the compression of its codebook. The VQ algorithm typically generates an index matrix and a codebook to represent compressed images. The proposed method focuses on reducing the size of the codebook, which comprises N codewords, each with elements quantized into four levels. Each 8-bit element in a codeword is compressed to 2-bits, and the encoded codeword is accompanied by the minimum value and a threshold value in the codebook. Experimental results on benchmark color images, such as baboon, airplane, Lena, and others, demonstrate a significant reduction of 62.50% in the size of the VQ codebook