VNUHCM Journal of Engineering and Technology

Build-up an analysis model to evaluate wind potential for selecting suitable turbine configurations and proposing research to optimize wind farm design

2025-05-02T01:48:55+07:00

Before a wind farm is constructed, the assessment of wind potential in the proposed turbine installation area must be carried out as a prerequisite. To achieve the highest efficiency, the key concepts and a deep understanding of wind energy evaluation must be mastered by the design engineers. The article of study applies Weibull distribution theory and aerodynamics fundamental to build an analytical model for evaluating standards and estimating annual electricity output based on raw input data collected over a year. The calculation results for the wind characteristics, including shape and scale factor and power density at the surveyed area corresponding to an 80m height, are determined in detail by simulation software. The analysis results also indicate that the wind potential here is classified as very high (class 6), and a minimum II-A type turbine configuration must be selected to withstand these wind conditions.

Since the initial investment cost of a wind farm will be determined by the simulation results, the study aims to combine the calculation methods used in this research with the application of digital twin solutions and machine learning for wind farms to create an accurately digital replica of a physical system. In this way, real-time system operations will be monitored and continuously updated into the simulation model to understand and predict its behavior. From there, optimal design and operation adjustments will be made to enhance the overall system's efficiency and minimize errors and risks for investors.

Nondestructive damage identification in beam-like structures via mode shape-based wavelet analysis method and artificial neural networks

2025-05-02T09:40:32+07:00

The development of non-destructive methods for structural health monitoring is essential. In recent years, research has required interdisciplinary and cross-disciplinary integration such as civil engineering, digital signal processing, and artificial intelligence. This integration aims to improve the efficiency and accuracy of the structural health monitoring method. From the research motivation, this paper proposes a nondestructive damage identification in beam-like structures using mode shape-based Wavelet analysis method and artificial neural networks (ANNs). Firstly, the theory of the Wavelet analysis method and the ANNs is described. Then, a finite element model of a simply supported beam is simulated. The investigated damage scenarios include cases of one, two, and three damage locations with different damage levels on the beam. The reliability of the simulation results is validated by comparing the numerical natural frequencies with theoretical results. Finally, the occurrence, location, and level of damage on the beam are accurately identified by using the proposed method. The results of this study demonstrate that the mode shape-based Wavelet analysis method, when combined with ANNs, achieves high effectiveness for damage identification in beam-like structures.

Application of Scan-to-BIM and geographic information systems in restoring the current status of buildings

2025-05-07T17:11:24+07:00

Because many existing structures, such as administrative, heritage, or university buildings that were constructed several decades prior, do not have sufficient paperwork and plans, the digital restoration of records for future management is currently facing a great deal of difficulty. Once the Building Information Modeling (BIM) information model is constructed, establish a connection and transmit the database via the Geographic Information Systems (GIS) environment to enhance the efficiency of project design, construction, and operation management. This will also serve as a database for future Smart city initiatives. Additionally, the traditional techniques of assessing existing conditions are labor-intensive and time-consuming, and the drawings of the as-built state are not necessarily correct. This study was carried out to enable the restoration of three-dimensional models of buildings by utilizing cutting-edge technologies such as BIM-GIS. The purpose of this study was to solve the problem that had been identified for Asset Management in Old Building. Building B6, which houses the Faculty of Civil Engineering at Ho Chi Minh City University of Technology (HCMUT), Vietnam National University, Ho Chi Minh City, serves as the case study for this kind of investigation. The first thing that has to be done is to use Scan-to-BIM to create a digital model of Building B6, and then the next step is to upload the BIM model to the GIS platform and check the conflict between each model thereafter. In conclusion, the study comes to a close by presenting its findings and providing an outline of potential future research topics.

Phân tích ứng xử động của tấm nhiều lớp chịu tải trọng di chuyển với gia tốc thay đổi và ảnh hưởng nhiệt độ

2025-05-12T15:39:15+07:00

Bài báo này xây dựng lý thuyết và phương pháp số mới để phân tích ứng xử động của tấm nhiều lớp đặt trên nền Pasternak chịu tải trọng di động với gia tốc thay đổi và xét ảnh hưởng của nhiệt độ. Phương pháp được nghiên cứu trong bài báo là phương pháp tấm nhiều lớp chuyển động MMPM (Multi-Layer Moving Plate Method). Ngoài ra, bài báo sử dụng lý thuyết tấm dầy Mindlin và nguyên lý công ảo để thiết lập phương trình chủ đạo mô tả chuyển động tấm và lực tác động. Tấm sau đó được rời rạc thành các phần tử 9 nút bằng phương pháp MMPM, và ghép nối các ma trận phần tử vào ma trận tổng thể để thu được phương trình chuyển động tổng quát của tấm nhiều lớp. Phương trình tổng quát này được giải bằng phương pháp Newmark để cho ra kết quả có hội tụ. Bài báo thực hiện được kiểm chứng với các kết quả thu được ở trường hợp tải tĩnh và tải động để so sánh với các công trình đã công bố nhằm chứng minh độ tin cậy của các kết quả trong nghiên cứu này. Tiếp theo, bài báo khảo sát các bài toán với những giá trị gia tốc khác nhau để xem xét sự ảnh hưởng của đại lượng này tới ứng xử tấm. Đồng thời, ảnh hưởng nhiệt độ được xem xét đến chuyển vị của tấm bằng cách đặt nhiệt độ tại mặt trên của tấm khác với nhiệt độ tại mặt dưới của tấm.

Trajectory planner based on fifth-order polynomials applied for lane changing in autonomous driving

2025-05-14T05:42:22+07:00

The control of autonomous cars is currently a topic of significant interest, primarily owing to their inherent advantages. These cars have the potential to enhance safety, decrease fuel consumption, thereby reducing travel costs, improve driving comfort, and alleviate traffic congestion. The control of car dynamics remains an open subject, with numerous researchers and companies striving to enhance existing strategies or develop novel ones. The developed solutions should aim to assist the driver while simultaneously ensuring safer driving conditions. Therefore, this paper proposes a solution for controlling the lateral of a car using model predictive control (MPC) algorithm includes decision making and trajectory planning. The initial step involves modeling the dynamics by constructing a nonlinear model based on the laws of physics, specifically considering the lateral aspects of a vehicle. Secondly, a trajectory planner is designed to ensure a safe path in the presence of the front car on the road, incorporating safety constraints. The host car is capable of executing lane shifts, overtaking, or braking maneuvers to avoid collisions with the front car. Thirdly, the trajectory generated by the planner is tracked using a Model Predictive Control (MPC) algorithm. The effectiveness of the proposed algorithm has been assessed through simulation.