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关键词： Finite element analysis   Truss elements   Beam elements   MATLAB  

摘要： The on-demand design of metamaterials such as lattices and bar structures is typically approached using computational methods due to their inherent complexity. An indispensable element of structural design is a reliable and easy to use FE simulation environment, which in turn not only benefits the design of underlying structures, but also, through easy customization and integration, propels the design of computational methods themselves. In response, this work provides a linear truss and beam FE simulation environment written in MATLAB. The simulation environment supports linear truss elements, Euler-Bernoulli besam elements, and Timoshenko beam elements. It further supports the introduction of self-weight and local truss buckling analysis. A variety of input methods are supported, these are specifically tailored towards simplifying the integration of the FE simulation environment in numerical optimization schemes. With this environment, researchers and design practitioners can easily simulate the mechanical response of complex bar structures without the need for interfacing with commercial FE software through cumbersome Application Programming Interfaces (APIs).

关键词： TiO2-Al2O3/H2O and Ag-MoS2/H2O hybrid nanofluid   Heat source-sink   Thermal radiation   Cattaneo-Christov heat flux   Melting phenomenon   Disk   Shooting approach   MATLAB  

摘要： The study of nanofluids using a stretchy disc has lately gained importance in fluid mechanics. This work investigates the impacts of the Cattaneo-Christov model, heat radiation, and melting events on TiO2-Al2O3/water and Ag-MoS2/water hybrid nanofluids over a disc. The results show that hybrid nanofluids greatly increase the thermal conductivity and heat transfer capabilities of base fluids. Water-based hybrid nanofluids are used in military applications such as solar thermal energy, heating pumps, heat exchanger devices, ships, air cleaners, the automotive industry, electric chillers, nuclear-powered systems, turbines, and equipment. To explain the flow of hybrid nanofluids, the two-dimensional nonlinear governing equations, which include the continuity, momentum, and heat transfer rate equations, are expressed in a non-dimensional form. The bvp4c solver firing technique in MATLAB is used to solve these non-dimensional equations and investigate the physical effects of various parameters on velocity and temperature profiles. Increasing the magnetic parameter and nanoparticle volume fraction substantially affects the velocity profile in opposing flow. Greater values of the thermal radiation and heat source-sink parameters result in a greater temperature profile. In addition, raising the thermal relaxation and melting parameters improves the temperature profile. The study's findings may be utilized in various sectors, including drainage, chemical engineering, solar panels, solar absorption and filtration, groundwater hydrology, solar cells, and other sheet flow applications.

关键词： Federated Neural Collaborative Filtering   Functional Linked Neural Network   Improved Black Hole optimization algorithm   Variational Density Peak Clustering   MATLAB  

摘要： In this paper, the Classification of Diabetic Retinopathy based on Functional Linked Neural Network utilizing Segmented Fundus Image Features (CDR-FLNN-SFI) is proposed. The input fundus images are collected utilizing the DIARETDB1dataset. The input image is pre-processed using Federated Neural Collaborative Filtering method. In pre-processing phase, the unwanted noises from input pictures are removed. Then, pre-processing output is segmented by using Variational Density Peak Clustering. Functional Linked Neural Network (FLNN) is utilized to categorize fundus images into normal, abnormal. The proposed model is implemented on MATLAB2018b. System performance is measured utilizing various metrics including precision, specificity, sensitivity, F1-Score, kappa score, computational time, error rate, accuracy and RoC. The proposed method significantly improves fundus image DR detection performance. The proposed CDR-FLNN-SFI technique attained the greater accuracy of 99.87%, precision of 98.34%, F1-Score of 97.41%. The proposed approach intends to decrease computational time and increase accuracy. In fact, presentation of proposed approach associated additional existing methods utilizing DIARETDB1dataset. The performance of the proposed CDR-FLNN-SFI is evaluated to the existing techniques like deep learning manner based on segmented fundus image features organization of diabetic retinopathy (DLA-SFI-CDR), Fundus image lesion finding process for diabetic retinopathy screening (FILDA-DRS), improved swarm optimization-based deep neural network for diabetic retinopathy organization fundus pictures (ESO-DNN-CDR) respectively.

关键词： MATLAB   Unconfined compressive strength   Bulk density   Least-squares regression   ANFIS   Artificial intelligence   Prediction performance   STRENGTH  

摘要： This study was carried out within the offshore Niger Delta Basin to generate novel predictive models for estimating rock parameters. MATLAB was employed in obtaining models for four different rock parameter relationships including unconfined compressive strength (UCS) against bulk density, UCS against sonic transit time (STT), shear wave velocity against STT, and permeability against bulk density using multiple ordinary least-squares regression (OLSR) methods. Also, the Adaptive-Neuro Fuzzy Inference System (ANFIS) artificial intelligence network was utilized for modeling and optimization of the data. Statistical tools including the Sum of Squares Total (SST), the Sum of Squares Error (SSE), the Sum of Squares Regression (SSR), and Correlation Coefficient (R-squared) were applied in investigating the prediction performances of the models. Results of OLSR analysis show that only the UCS against bulk density model gave high prediction performance in all the OLSR models with R-squared values of 0.8637, 0.8848, 0.8216, 0.9956, and 0.8108 for linear, quadratic, power, logarithmic, and exponential models respectively. ANN model results revealed that UCS against bulk density, UCS against STT, and shear wave velocity against STT models all gave high prediction performances with respective R-squared values of 0.89635, 0.99365, and 0.52703, while the permeability against bulk density model gave low performance (0.03378). These findings imply that all the OLSR models can be applied for the prediction of rock UCS from bulk density information only, while ANN-generated models can be used in predicting UCS from bulk density and STT, in addition to shear wave velocity from STT in the study area and similar geologic environments.

关键词： Laser beam shaping   Digital micromirror device   Digital holography   Structured light   GENERATION   LIGHT  

摘要： The growing interest in the application of structured light has led to an increase in the use of spatial light modulators across users at all levels of experience. Hence, there is a need for software that controls the device, designs holograms and gathers experimental feedback. To meet these demands we present the Binary Complex Amplitude App- a standalone Matlab application that provides a graphic user interface with a full control of the Digital Micromirror Device, enabling hologram design and camera preview. We show that with all-in-one application, the user at any level of experience can operate the device and do not lose any of its capabilities.

关键词： Additive manufacturing   Lattice structures   Triply periodic minimal surfaces (TPMS)   Open-source software   Grading   MATLAB   Design   Hybridization  

摘要： Triply Periodic Minimal Surfaces (TPMS) are parametrically generated lattices with topology-driven properties. They are emerging as a significant innovation, finding wide-ranging applications. This paper introduces LattGen, a software solution that addresses the complexity of designing these surfaces. This tool allows users to easily customize their desired surfaces' size, volume fraction, grading, and hybridization. LattGen also allows for the import of arbitrary domains and the export to standard computer-aided design platforms for additive manufacturing. This design platform automates the creation of porous structures, making them a valuable tool in various scientific, engineering, and creative fields.

关键词： Machine learning   Heat exchanger   Optimization   MATLAB   Reliability prediction  

摘要： The experimentation and analysis of a machine learning (ML) algorithm for automatic problem detection and real-time heat exchanger optimization (RTHEO) is presented in detail in this paper. Preparing datasets, optimizing heat exchanger parameters, identifying problems, self-training, and applying machine learning algorithms are the main areas of study. The suggested method utilizes MATLAB Simulink simulations that use polynomial regression to suggest parameters and a combination of algorithms to identify anomalies. The program continuously obtains real-time data, compares it with previous patterns, and notifies the user if any anomalies are detected. The algorithm adapts to observations through self-training, ensuring accurate and reliable predictions. The implementation is carried out using MATLAB, with robust error-handling mechanisms for real-world applications. The simulation procedure is discussed, and a future experimental setup is proposed to verify the program's performance.

关键词： Power conversion   Duty Ratio   MATLAB   Variable Voltage   Variable Frequency   MATRIX   CONVERTERS  

摘要： This research presents a novel direct AC-to-AC topology for converting power from three phases (3 phi) to five phases (5 phi). The power conversion is handled by a Quasi Z Source Direct Matrix Converter (QZSDMC). This device is made up of a regular Direct Matrix Converter (DMC) and a pseudo Z-source impedance network that are serially connected. The proposed QZSDMC receives alternating current power in 3 phi at a fixed voltage and frequency and outputs it in 5 phi at a variable voltage and frequency to a standalone system. You can switch between buck and boost mode with a couple of switch flips. The shoot-through Duty Ratio value might help us understand the voltage transferal ratio. The authors suggested a unique control mechanism based on Direct Duty Ratio Pulse Width Modulation (DDRPWM) in this work. The method described here is only relevant when the amount of output phases is odd, not even. The paper uses MATLAB tools and experimental results to show the proposed system's operational principle in detail and prove its viability. Here, buck and boost conditions in all four quadrant modes with the proposed QZSDMC architecture, and the voltage gain constraint are addressed. It is more dependable, more efficient, and less expensive than a traditional back-to-back converter (B2BC).

关键词： ESP-32S   IoT   MATLAB   Smart agriculture   Remote monitoring   ThingSpeak  

摘要： With the progress in sensor and cloud technologies in contemporary times, a range of intelligent agriculture applications has gained considerable prominence. It is predicted that these developments can continue to pique the interest of researchers in the future. On the other hand, it is seen that IoT (Internet of Things)-based models are used in various fields. Herein, the primary objectives of this study are to enable farmers to remotely monitor and manage field conditions through sensor technology and IoT integration. In addition, these technological advancements make it possible to take the required measurements. Farmers can optimize their agricultural practices based on the analysis of the data obtained for this application. Thus, the aim is to manage the agricultural process more effectively and efficiently. In this study, an IoT-based framework is proposed for agricultural data monitoring. Light, temperature-pressure, smoke, humidity, and soil dryness values can be measured from GY-30, BME280, MQ-2, DHT11, and YL-69, respectively. An ESP-32S development board is used to collect data from sensors, and this board is coded using Arduino IDE. Subsequently, using ESP-32S, it is sent to the ThingSpeak cloud service provided by MATLAB via a Wi-Fi connection. Thus, these data can be easily transferred to MATLAB. We create a user-friendly Graphical User Interface application so that the data can be monitored and analyzed in MATLAB as well as ThingSpeak. This application allows users to monitor the data flow in real time and can easily provide the requested values such as maximum, minimum, mean, standard deviation, and current with the help of a button. In addition, the proposed system sends an e-mail to the user when soil dryness and smoke values exceed a certain threshold value. The results obtained in the study indicate that the proposed model can save time and labor in addition to providing reliable and fast data flow.

关键词： Model-based development   MATLAB   Simulink   Tools and techniques   Experimental evaluation   FAIR principles   Replicability   Systematic literature review   SELECTION  

摘要： Research on novel tools for model-based development differs from a mere engineering task by not only developing a new tool, but by providing some form of evidence that it is effective. This is typically achieved by experimental evaluations. Following principles of good scientific practice, both the tool and the models used in the experiments should be made available along with a paper, aiming at the replicability of experimental results. We investigate to which degree recent research reporting on novel methods, techniques, or algorithms supporting model-based development with MATLAB/Simulink meets the requirements for replicability of experimental results. Our results from studying 65 research papers obtained through a systematic literature search are rather unsatisfactory. In a nutshell, we found that only 31% of the tools and 22% of the models used as experimental subjects are accessible. Given that both artifacts are needed for a replication study, only 9% of the tool evaluations presented in the examined papers can be classified to be replicable in principle. We found none of the experimental results presented in these papers to be fully replicable, and 6% partially replicable. Given that tools are still being listed among the major obstacles of a more widespread adoption of model-based principles in practice, we see this as an alarming signal. While we are convinced that this situation can only be improved as a community effort, this paper is meant to serve as starting point for discussion, based on the lessons learnt from our study.