Miracle-dz/UniFAR-FTUs huggingface dataset:
Numerical Analysis of Magnetic and Plasma Characteristics of the DC Ring Cusp Discharge Ion Thruster

Electric propulsion systems are developed as efficient satellite propulsion systems over the years. In the electric propulsion arena, three main thruster models can be seen in worldwide space applications. They are electrothermal, electrostatic, and electromagnetic thrusters. Direct Current (DC) ring cusp discharge ion thruster is an electrostatic class ion thruster. It is also highly anticipated that ion thruster’s collective thrust in space will lead to space explorations. This study mainly focuses on the numerical analysis of the magnetic and plasma characteristics of DC ring cusp discharge ion thruster. In the numerical model, basic concepts of ion thruster were presented with magnetic and plasma characteristics, performance and heavier species characteristics, and the variation of plasma density with, node voltage, pressure, grid perforation, and the magnetic field. The magnetic characteristics of the ion thruster were modeled using two dimensional (2D) axisymmetric model with three magnetic rings. In addition, a three-dimensional (3D) revolution model is also presented to investigate the full-scale ion thruster. Also, the plasma characteristics including ion densities were analyzed using finite element numerical, 2D fluid axisymmetric model, and 3D revolution model to evaluate the ion distributions.
UAV Based Satellite-Terrestrial Systems With Hardware Impairment and Imperfect SIC: Performance Analysis of User Pairs

We investigated the outage performance of non-orthogonal multiple access (NOMA) in satellite-terrestrial systems which contain hardware impairments. An unmanned aerial vehicle (UAV) was implemented to forward signals from a satellite to users on the ground. A two-user model was applied to achieve spectral efficiency. In practical, real-life scenarios, the UAV and ground users encounter issues with imperfect hardware. We examined the performance gap between two users experiencing practical problems such as hardware impairment and imperfect successive interference cancellation (SIC). To implement a practical scenario, Shadow-Rician fading was adopted in the satellite links, and Rician fading was employed in the terrestrial links for ground users. In the main results, we derived the closed-form expression of the outage probability, and to evaluate the system performance of two NOMA users, we obtained the approximate expressions for high signal-to-noise ratios (SNR). Finally, we produced Monte-Carlo simulations to verify the analytical expressions and demonstrate the effect of the main system parameters, such as the number of transmit antennas on the satellite, transmit SNR, and level of hardware impairment on the system performance metric.
Low Computation and High Efficiency Sobel Edge Detector for Robot Vision

Most information in an image is contained in the edge. Sobel edge detection algorithm is a classic method to realize the edge detection of image in the applications of robot vision, including motion detection and object tracking. This paper proposes an area-efficient and energy-efficient Sobel edge detector design utilizing bit-width pruning, shift-add operation and bit-width tuning techniques, to reduce required area and computation significantly with negligible edge information loss, for mobile robot vision applications. As a result, the proposed Sobel edge detector can achieve lower hardware overhead and higher energy efficiency. FPGA implementation shows that the proposed Sobel detector design achieves 33% lower power consumption while maintaining a good detection performance in terms of CP (over 99%, $P_{co}$) and achieving a better processing performance in terms of frame rate (an increasing by 39.5%), as compared to the conventional Sobel detector design, which is suitable for resource-limited and energy-constrained mobile robots in edge IoT applications.
Efficient Bee Identification

The bee-identification problem, formally defined by Tandon, Tan and Varshney (2019), requires the receiver to identify “bees” using a set of unordered noisy measurements. In this previous work, Tandon, Tan and Varshney studied error exponents and showed that decoding the measurements jointly results in a significantly smaller error exponent. Here, we study efficient ways of performing joint decoding. First, by reducing to the problem of finding perfect matching and minimum-cost matchings, we obtain joint decoders that run in time quadratic and cubic in the number of “bees” for the binary erasure (BEC) and binary symmetric channels (BSC), respectively. Next, by studying the matching algorithms in the context of channel coding, we further reduce the running times by using classical tools like peeling decoders and list-decoders. In particular, we show that our identifier algorithms when used with Reed-Muller codes terminates in almost linear and quadratic time for BEC and BSC, respectively.
A Representation of System Solutions for Global Exponential Stabilization of Memristor-Based Neural Networks With Unbounded Time-Varying Delays

This article mainly discusses the global exponential stabilization of a class of memristor-based neural networks (MNNs) with unbounded time-varying delays. In this article, a new approach without constructing any Lyapunov–Krasovskii functional is proposed to derive the global exponential stabilization criterion containing only a few simple inequalities. This approach is based on the representation of the system solution, which can derive simpler criteria than the existing approaches. In addition, this approach does not limit the range of the derivative of the unbounded time-varying delay, which implies that the stabilization criterion obtained is weaker conservative. Finally, two numerical examples are employed to demonstrate the effectiveness of the approach.
A Review of Commonality Design for Civil Aircraft

With the change of market demand and the rapid development of serial civil aircraft, the concept of commonality is introduced into the field of civil aircraft and has been paid attention by large commercial aircraft manufacturers. In this paper, the basic concepts and indexes related to commonality are summarized by reviewing relevant literature on commonality, as well as the relevant applications of civil aircraft commonality design. Then it is discussed that the lifecycle offset and weakening of commonality in product family and the research direction of commonality in the future. This paper can provide some reference value for commonality design.
FT-MSTC*: An Efficient Fault Tolerance Algorithm for Multi-robot Coverage Path Planning

Fault tolerance is very important for multi-robot systems, especially for those operated in remote environments. The ability to tolerate failures, allows robots effectively to continue performing tasks without the need for immediate human intervention. In this paper, we present a new efficient fault tolerance algorithm for multi-robot coverage path planning (mCPP). The entire coverage path is considered as a topological task loop. The ideal mCPP problem is handled by partitioning this task loop and assign each partition to individual robot. When a faulty robot is detected, we use an optimization method to minimize the overall maximum coverage cost while considering both the tasks accomplished before robot failures and the remaining tasks. We perform various experiments for regular grid maps and real field terrains. We compare our algorithm against other coverage path planning algorithms and our algorithm outperforms existing spiral-STC-based methods in terms of the overall maximum coverage cost.
Efficient and accurate PLIC-VOF techniques for numerical simulations of free surface water waves

In this paper the attention is focused on the effect of various VOF methods on efficient and accurate simulation of free surface water waves. For this purpose, we will compare several VOF methods in numerical simulations of propagating waves where strong nonlinear behavior is dominant in the flow. Comparisons and discussions will be provided to underline the significance of free surface modeling on the accuracy of wave propagation.
Bent Sequences over Hadamard Codes for Physically Unclonable Functions

We study challenge codes for physically unclonable functions (PUFs). Starting from the classical Hadamard challenge code, we augment it by one vector. Numerical values suggest that the optimal choice of this vector for maximizing the entropy is to pick a vector the farthest away from the code formed by the challenges and their binary complements. This leads us to study the covering radius of Hadamard codes. A notion of bent sequence that generalizes the classical notion from Hadamard matrices of Sylvester type to general Hadamard matrices is given. Lower bounds for Paley-type Hadamard matrices are given.
Communication Among Heterogeneous Unmanned Aerial Vehicles (UAVs): Classification, Trends, and Analysis

In the past decade, unmanned aerial vehicles (UAVs) have become a major research topic in robotics, despite their existence since 1915. UAVs can perform various activities efficiently and effectively; therefore, involving a group of UAVs in performing a certain task has become a growing research trend. Research involving multiple UAVs has been carried out in various areas such as force protection, warfare in the military, remote sensing, disaster response activities, and surveillance. While performing critical tasks, efficiency and robustness are important considerations that can be achieved by involving heterogeneous UAV teams with effective communication and coordination techniques. Communication among heterogeneous UAVs is an interesting and critical research area that needs to be thoroughly explored. In this research, an evidence-based approach is adopted to explore research carried out on multiple heterogeneous UAVs and their communication patterns while performing various activities. A mapping study research technique is employed to systematically collect, analyze, and assess the evidence available on the topic under discussion. The time period defined for this study was set from 2005 to 2019, and 46 primary studies were considered for thematic analysis. The findings show that research studies fall under the category of validation research by constructing simulations to provide a proof-of-concept implementation of the proposed solutions. The communication patterns among heterogeneous UAVs involve various components of UAV communication, networking, formation, and path planning. The application areas that were largely focused on were search, rescue, monitoring, and surveillance missions. The overall trend showed that interest in multiple heterogeneous UAV usage increases over time with a focus on UAV networks, formations, and path planning while considering communication as an implicit part of all these structures. This research has conducted an in-depth analysis of existing research on heterogeneous UAVs and provides classification and trends of various themes emerging within this research area.
Gestures recognition of sEMG signal based on Random Forest

The surface electromyographic (sEMG) signal is a bioelectric signal generated by muscle activity collected from the human epidermis, which contains rich information about muscle activity, and the EMG signal caused by different movements is different, which can reflect the different movement states of human limbs. Therefore, by collecting, processing and feature extraction of sEMG signals, it can realize the recognition of human hand movements, and can be used as the control source of the prosthesis to realize the control of the prosthesis. In this paper, we propose a Random Forest algorithm-based model for sEMG signal processing and human hand movement recognition, and design an EMG signal conditioning circuit for the acquisition and conditioning of sEMG signals of arm muscles, and store the data using a NI data acquisition card. At the same time, the random forest model is trained using the public dataset to realize the classification of four kinds of actions: Fist clenching, Hand opening, Wrist internal rotation and Wrist external rotation, which provides a new method and idea for hand gesture action recognition and also facilitates further research work in the follow-up.
Study of Interaction Methods in Virtual Electrician Training

Virtual, Augmented and Mixed Reality technologies can be applied to improve competences of serviceman, or generally employees dealing with technical systems. The paper describes results of a first stage of development of a VR training system dedicated to electricians, working for one of Poland’s major electricity providers. Three methods of interaction with the virtual environment and three navigation methods have been implemented in the presented application. To choose the best method of interaction and navigation in the training application, 30 electricians tested different combinations of methods in two training scenarios. Each participant went through the scenario twice, using two different navigation modes for the same interaction mode and scenario. The time of each pass was measured and the participants filled in a questionnaire to give feedback on their subjective impressions of using a given mode. Based on the gathered data analysis, the best interaction and navigation methods have been selected. These initial results will improve interaction and navigation at the next stage of the application development and implementation in the enterprise.
The OPAQUE1/DISCORDIA2 myosin XI is required for phragmoplast guidance during asymmetric cell division in maize

Formative asymmetric divisions produce cells with different fates and are critical for development. We show the myosin XI protein, OPAQUE1 (O1), is necessary for asymmetric divisions during maize stomatal development. We analyzed stomatal precursor cells prior to and during asymmetric division to determine why o1 mutants have abnormal division planes. Cell polarization and nuclear positioning occur normally in the o1 mutant, and the future site of division is correctly specified. The defect in o1 occurs during late cytokinesis, when the phragmoplast forms the nascent cell plate. Initial phragmoplast guidance in o1 is correct; however, as phragmoplast expansion continues o1 phragmoplasts become misguided. To understand how O1 contributes to phragmoplast guidance, we identified O1-interacting proteins. Maize kinesins related to the Arabidopsis thaliana division site markers PHRAGMOPLAST ORIENTING KINESINs (POKs), which are also required for correct phragmoplast guidance, physically interact with O1. We propose that different myosins are important at multiple steps of phragmoplast expansion, and the O1 actin motor and POK-like microtubule motors work together to ensure correct late-stage phragmoplast guidance.
Transducer Arrays Over A²B Networks in Industrial and Automotive Applications: Clock Propagation Measurements

Advanced automotive applications like Active Noise Cancellation (ANC) and Individual Listening Zones (ILZ) require a high number of transducers (i.e., microphones, accelerometers, and loudspeakers) usually arranged as arrays. Transducer arrays are widely employed in several applications besides automotive field, such as teleconferencing systems, industrial and civil monitoring of noise and vibrations. Automotive Audio Bus (<inline-formula> <tex-math notation="LaTeX">$\text{A}^{2}\text{B}$ </tex-math></inline-formula>) is an audio transport protocol that solves the latest requirements of automotive and industrial fields. <inline-formula> <tex-math notation="LaTeX">$\text{A}^{2}\text{B}$ </tex-math></inline-formula> allows transporting up to 32 channels in a multi-node daisy chain network and guarantees synchronization and low deterministic latency. This paper aims to develop a clock propagation model of an <inline-formula> <tex-math notation="LaTeX">$\text{A}^{2}\text{B}$ </tex-math></inline-formula> network composed by transducer arrays. This model will be useful to evaluate the impact of the bus on the array performance. Firstly, a theoretical description of the <inline-formula> <tex-math notation="LaTeX">$\text{A}^{2}\text{B}$ </tex-math></inline-formula> protocol and jitter analysis is provided. It follows a description of the jitter measures carried out on the clocks distributed along the <inline-formula> <tex-math notation="LaTeX">$\text{A}^{2}\text{B}$ </tex-math></inline-formula> network. Lastly, latency introduced by nodes of the network is investigated.
A new sEMG signal feature extraction method based on S transform

The motion state of the human lower limbs can be reflected by the sEMG signals of the lower limbs muscles. Therefore, extracting features that are distinguishable between different actions can reduce the computational cost of the classification model and improve the accuracy of action classification. This paper proposes a Stockwell transform's singular values concentration measure (ST-SCM) feature extraction method. In order to verify the advantages of the algorithm proposed in this paper, we collected the raw sEMG signals of 10 experimenters' lower limbs movements, and based on these original data, performed verification experiments on the classification performance of ST-SCM. Through three comparative experiments, we compared the classification performance and running time of the ST-SCM feature extraction method with the other five feature extraction algorithms. The experimental results show that the accuracy of this method is 96.19% in the classification of 6 types of single joint movements of the lower limbs, and the running time is relatively fast. Compared with the other five feature extraction algorithms, this feature extraction method can improve the accuracy and reliability of lower limb movement classification.
Improvement of “Kinnow” mandarin fruit productivity and quality by urea, boron and zinc foliar spray

ABSTRACT The present study was carried out on Kinnow mandarin trees (Citrus reticulata Blanco) to study the effect of urea, zinc (Zn) and boron (B) foliar sprays either alone or in combinations on fruit yield and quality. Trees were grown in alkaline sandy loam soil at Dirab, Riyadh, Saudi Arabia. All trees were sprayed twice: before full bloom (February) and after fruit set (April) during two growing seasons. The obtained results showed a significant increase in tree yield and enhancement in fruit physical characteristics (fruit weight, pulp, juice, volume, length and diameter), as well as fruit chemical characteristics [soluble solids content, acidity, pH, total sugars and ascorbic acid] by all foliar treatments in comparison with the control (water only) in both seasons. Spraying urea in combinations with B and Zn resulted in higher fruit yield and better physico-chemical characteristics as compared with urea only, urea + B or urea + Zn.
Cyclodextrin-based molecules as hosts in the formation of supramolecular complexes and their practical applications—A review

Abstract The excellent biocompatibility and unique inclusion capability as well as powerful functionalization capacity of cyclodextrins and their derivatives make them especially attractive for engineering novel functional materials for many applications. There has been increasing interest recently to fabricate supramolecular systems based on cyclodextrin materials. This review focuses on state-of-the-art and recent advances in the construction of cyclodextrin-based assemblies and their practical applications in many fields like gene therapy, chemotherapy, antimicrobial drug delivery, metal extraction, food industry, etc. Supramolecular self-assembly materials based on cyclodextrins are also discussed in this review. The fabrication technologies of supramolecular systems including nanoplatforms and hydrogels as well as their applications in nanomedicine and pharmaceutical sciences are highlighted. In the end, the future directions of this field are discussed.
High-Precision Pose Estimation Method of the 3C Parts by Combining 2D and 3D Vision for Robotic Grasping in Assembly Applications

Using robots to replace manual production has been seen as a feasible solution to reduce production costs and increase productivity, especially in the 3C (Computer, Communication, and Consumer Electronics) products assembly lines, which rely heavily on labor. Due to the characteristic of small size and accurate fitting precision, small uncertainties in the assembly process will lead to the failure of the assembly, especially in the process of grasping, when the gripper needs to move to a certain position. So, to realize the 3C products flexible assembly of the robot, machine vision is required to provide the high-precision pose information of the object. So far, point cloud based 6D (6-dimensional) pose estimation algorithms have attracted the attention of many researchers because point cloud can provide three-dimensional information directly. However, the disorder of the point cloud and the background information with miscellaneous noise makes it impossible to directly estimate the pose of the target object with high precision. To deal with this problem, we propose a 2D-3D combined high-precision pose estimation method. The whole method is divided into two stages. In the first stage, the mask of the object in the 2D image is identified through the Mask R-CNN which is trained through fine-turning. In the second stage, we use a structured light camera to generate the point cloud and map the mask to it to extract useful point cloud, then the high-precision pose estimating algorithm composed by PCA-ICP is used to get the global pose of the part. Finally, the pose is converted to the robot coordinate frame by the result of hand-eye calibration. The proposed method is verified by the grasping and assembly experiments.
Application of Improved NSGA-II Algorithm in Ship Entry and Exit Dispatching

In order to reduce the detention time of ships in the port, make full use of port resources and optimize port services. This paper analyzes the factors that affect the efficiency of the dispatching of ships entering and leaving the port, and studies the coordinated dispatching of multiple ship types and multiple berth types. Based on the proposed hypothesis, with the minimum total scheduling time and the minimum waiting time as the optimization goals, a coordinated scheduling model for berth allocation and channel was established. Based on the NSGA-II algorithm, a multi-objective optimization genetic algorithm suitable for solving the model of berth allocation and channel coordination scheduling is designed. By testing the intensive ship entry and exit data in a short period of time, the solution efficiency and stability of the algorithm in this paper are better than those of the NSGA-II algorithm, and it is more suitable for solving the optimization problem of berth allocation and channel coordination scheduling.