This paper proposes a novel method to quantify the error of a nominal normalized right graph symbol (NRGS) for an errors- in-variables (EIV) system corrupted with bounded noise. Following an ...identification framework for estimation of a perturbation model set, a worst-case v-gap error bound for the estimated nominal NRGS can be first determined from a priori and a posteriori information on the underlying EIV system. Then, an NRGS perturbation model set can be derived from a close relation between the v-gap metric of two models and H∞-norm of their NRGSs' difference. The obtained NRGS perturbation model set paves the way for robust controller design using an H∞ loop-shaping method because it is a standard form of the well-known NCF (normalized coprime factor) perturbation model set. Finally, a numerical simulation is used to demonstrate the effectiveness of the proposed identification method.
This paper designs an indoor visible light communication application system based on LED. The system can modulate the original signal one or more times, move to a specific frequency band, transmit on ...the power line, in the LED terminal use this module to decode, restore the Ethernet signals. This design is applicable to the simplicity of the LED visible light communication applications, which provide the premise and guarantee for the construction of smart home network.
In wind farms with high integrated automation systems, different communicated structures, such as different communication protocols and communication mediums, exist among various intelligent ...equipment. Different communication protocols or media will lead to incompatibility of communication between various intelligent devices. Developing communication protocol converters is an effective way to solve such problems. In this way, the communication efficiency between intelligent devices will be affected to some extent, and then the operation of the whole wind farm will be affected. This study introduces a communication protocol converter integrated with a multiserial, multiprotocol, and multinetwork system. The protocol converter treats the microcontroller STM32F407 as the microcontroller unit of the converter to integrate multiple communication interfaces. Meanwhile, the compatibility problems of communication between the intelligent equipments in the wind field monitoring system can be solved using software to realize the conversion between the various communication protocols.
With the continuous decrease of arable land, the emergency of plant growth cabinet can efficiently provide people with more high quality green vegetables. The reasonable density in plant growth ...cabinet becomes our primary problem. The key to reasonable density is reasonable planting density, that is to say, a large coefficient of leaf area (but not too big) is needed. Vegetable leaf’ quantity and the size of the leaf area can reflect whether the plants are in a good condition. It is the key to a reasonable density. But in the process of calculating vegetable leaf number, a problem is that leaves may block each other, which is not desired in subsequent statistic. Therefore this paper proposes a watershed segmentation based on improved marker control in order to get the number of connected components or the number of leaves. The experiment shows that this method can separate the overlapping leaf images effectively and thus successfully solves the target adhesion phenomenon on the subsequent analysis and measurement of interference problem.
The state of crop growth can be reflected truly from prominent morphological characteristics of leaf vegetables' veins. Meanwhile, computer image processing technology enables these features to be ...extracted, which provide a significant method to master the vegetables growing and allows the environment of plant growth cabinet to be controlled in intelligent way. This paper analyzes the histogram distribution of each channel firstly, and then combining the color channel combination operation with threshold segmentation to get the veins and blade profile images. After that, the blade edge is extracted through mathematical morphology. Lastly, this paper compares the absolute value between the profile images and the blade edge images to achieve precise segmentation and extraction of the veins. The results of experiments show that it is a better method to extract veins by means of the difference between mesophyll and the leaf color, allowing the manager to measure the crop growth and making it possible for intelligent monitoring used in plant growth cabinet.
The current yarn tube manipulator just finishes yarn tube grabbing work according to the fixed coordinates. In the actual production process, equipment problems or human factors which make the ...spindles not on fixed coordinates cause the damage of the manipulator. Real-time grabbing yarn tube system with visual sensing has been designed and a extraction algorithm of spindles coordinates based on a mixed image morphology and Hough transform algorithm has been proposed. Through the combination of the yarn tube image characteristics which are extracted by the algorithm and the visual measurement model which is established by pinhole imaging principle, the mapping relation of yarn tube image coordinates and world coordinates has been gained to get the location information of yarn tube in real time. Results show that the proposed method could make the robot complete the grabbing job precisely and efficiently, under which the system meet the requirement of spinning and dyeing production line.
Astaxanthin has superior antioxidant capacity, and Haematococcus pluvialis is recognized as the most powerful organism to accumulate natural astaxanthin in nature. In artificial culture, ...environmental factors can affect the yield of astaxanthin. In order to reduce blindness in the cultivation of Haematococcus pluvialis and effectively increase astaxanthin production, grey relational analysis was used to calculate the correlation between the culture factors and the growth condition of Haematococcus pluvialis, and advantage analysis was performed to investigate the influence degree of different culture factors on the growth and astaxanthin accumulation of Haematococcus pluvialis. The results showed that the effects of light intensity and temperature were greatest during the proliferative culture stage, while the effects of temperature and light duration were greatest during the astaxanthin induction stage. The application of grey relational analysis also provides a convenient reference tool for the design of research to improve the yield of astaxanthin induced by Haematococcus pluvialis, and other culture factors affecting astaxanthin yield can be analyzed and compared using this method, providing more ideas for optimizing culture methods and developing culture devices.
A remote lab is a technology that allows participants to efficiently conduct experimental teaching where users can connect to lab equipment from anywhere without being in a specific physical ...location. The COVID-19 pandemic affects all areas of human activity. As a result, students did not receive face-to-face instruction, and access to the laboratory was limited or practically impossible, and access to laboratory facilities has been limited or nearly impossible. Especially in engineering education, students’ practical abilities cannot be developed comprehensively. In this paper, this paper built an online remote robotics experiment system using digital twin (DT) technology and IoT technology and adopted ADDIE (Analysis, Design, Development, Implementation, and Evaluation) teaching method. With these measures, students can design and debug robot programs at home, just like in the laboratory. This study sent questionnaires to 64 students, and 58 were returned. The results show that more than 80% of students believe that the remote labs for industrial robotics courses have improved the efficiency and quality of students' skills training as opposed to virtual simulation and watching videos on the computer.
This paper deals with the distributed output regulation problem for the discrete-time nonlinear multi-agent systems based on fuzzy models. T-S fuzzy models are constructed to approximate the ...considered nonlinear multi-agent model, then we design the distributed feedback controller to guarantee the following agents asymptotically track the reference generated by an exosystem. The exosystem can be viewed as an active leader in the multi-agent systems, and the state of exosystem is assumed to be not completely measurable for each following agent. Finally, a numerical simulation example is provided to demonstrate the effectiveness of the obtained results.
This paper presents a novel method to solve the initial lightning breakdown current by combing ATP and MATLAB simulation software effectively, with the aims to evaluate the lightning protection ...performance of transmission line. Firstly, the executable ATP simulation model is generated automatically according to the required information such as power source parameters, tower parameters, overhead line parameters, grounding resistance and lightning current parameters, etc. through an interface program coded by MATLAB. Then, the data are extracted from the generated LIS files which can be obtained by executing the ATP simulation model, the occurrence of transmission lie breakdown can be determined by the relative data in LIS file. The lightning current amplitude should be reduced when the breakdown occurs, and vice the verse. Thus the initial lightning breakdown current of a transmission line with given parameters can be determined accurately by continuously changing the lightning current amplitude, which is realized by a loop computing algorithm that is coded by MATLAB software. The method proposed in this paper can generate the ATP simulation program automatically, and facilitates the lightning protection performance assessment of transmission line.