Miracle-dz/UniFAR-FTUs huggingface dataset:
Impedance Control of Hydraulic Actuation Systems With Inherent Backdrivability

The demand for high-performance impedance control in electro-hydraulic actuation systems is a mainstream issue in the robot actuation research community. Although various nonlinear model-based impedance controllers have been developed and showed good performance in recent years, they remain hindered by the high cost of force sensors, and accurate internal dynamics models need to be derived to overcome the non-backdrivability and complex dynamics of hydraulic systems. As a solution to these problems, this paper presents an impedance control approach for hydraulic systems that require no external force sensors or chamber pressure sensors with a pressure control servovalve or backdrivable servovalve. First, we show that a backdrivable servovalve brings inherent backdrivability to hydraulic systems, such that high-performance impedance control can be implemented without requirement of force sensors and exact knowledge on the dynamics of hydraulic chambers, owing to its torque-source property and low effective valve inertia on the link side. Second, utilizing the obtained backdrivability, we develop a passivity-guaranteed impedance controller. A momentum-based external torque observation algorithm is incorporated to render desired impedance over a wide range, without using force/torque sensor. The performance of the proposed backdrivable servovalve and impedance controller was verified through extensive experimental results.
Mechanical and Control Design of an Industrial Exoskeleton for Advanced Human Empowering in Heavy Parts Manipulation Tasks

Exoskeleton robots are a rising technology in industrial contexts to assist humans in onerous applications. Mechanical and control design solutions are intensively investigated to achieve a high performance human-robot collaboration (e.g., transparency, ergonomics, safety, etc.). However, the most of the investigated solutions involve high-cost hardware, complex design solutions and standard actuation. Moreover, state-of-the-art empowering controllers do not allow for online assistance regulation and do not embed advanced safety rules. In the presented work, an industrial exoskeleton with high payload ratio for lifting and transportation of heavy parts is proposed. A low-cost mechanical design solution is described, exploiting compliant actuation at the shoulder joint to increase safety in human-robot cooperation. A hierarchic model-based controller with embedded safety rules is then proposed (including the modeling of the compliant actuator) to actively assist the human while executing the task. An inner optimal controller is proposed for trajectory tracking, while an outer safety-based fuzzy logic controller is proposed to online deform the task trajectory on the basis of the human’s intention of motion. A gain scheduler is also designed to calculate the inner optimal control gains on the basis of the performed trajectory. Simulations have been performed in order to validate the performance of the proposed device, showing promising results. The prototype is under realization.
The Influence of Culture in IT Governance Implementation: A Higher Education Multi Case Study

IT governance calls for the definition and implementation of formal mechanisms at the highest level in the organization taking into account structures, processes and relational mechanisms for the creation of business value from IT investments. Several factors can influence IT Governance implementation success. Culture is one of these factors and the one this research will focus on. Seen as probably the most difficult factors to change since it is grounded on practices performed over time, it should receive special attention. This article aims to analyze how culture can influence IT Governance implementation of structure, process and relational mechanisms in the context of higher education. Ten case studies in universities from three different countries: Brazil, Portugal and Netherlands were carried out. The purpose is the identification of relevant differences in IT Governance implementation among organizations from the following cultures: uncertainty avoidance and individualism. This article concludes by presenting key contributions, limitations and future work.
Integrated lateral control for 4WID/4WIS vehicle in high-speed condition considering the magnitude of steering

Aiming at the difficulty of vehicle lateral control in high-speed condition, a comprehensive control method that integrates active steering (AS) and direct yaw moment control (DYC) systems is proposed for four-wheel independent driving and four-wheel independent steering (4WID/4WIS) vehicle. According to the characteristics of lateral dynamics in high-speed conditions, different principles are adopted in different steering conditions. In a slight or moderate steering, a decoupling control method is proposed, and a penalty function is used to allocate the involvement of AS and DYC for the over-actuated characteristics of 4WID/4WIS vehicle. While in a large steering, based on sideslip phase plane, handling-oriented and stability-oriented control are proposed in order to realise a fine trade-off between handling and stability performance. A transient layer is introduced in the phase plane to further improve the performance of this controller. And the allocation of active yaw moment is also discussed. Simulation results demonstrate that the proposed integrated control method can effectively improve the lateral dynamics performance of the vehicle in high-speed condition as compared to previous control methods.
Improving time integration scheme for FEM analysis of MTL problems

This paper presents improved algorithm for electromagnetic transient calculations on multiconductor transmission line (MTL) achieved by improvement of the time integration when forming a local system of equations for a finite element. Improvement of accuracy was obtained by using Heun's method. Previously developed local system of equations of MTL has been obtained using the generalized trapezoidal rule (ϑ‐method). The use of the generalized trapezoidal rule for the time integration sometimes causes numerical oscillations or numerical diffusion of numerical solutions. Numerical solutions obtained using Heun's method and using the generalized trapezoidal rule for different values of a time integration parameter are compared with analytical solution. It has been shown that Heun's method yields the results with much higher accuracy comparing to results obtained by generalized trapezoidal rule.
Dispatch framework of power system with heat storage facilities in combined heat and power plants for wind power accommodation

Heat storage (HS) instalment in combined heat and power (CHP) plants is a promising solution to increase the adjustability of CHP plants and reduce renewable energy curtailment. Despite the proposed optimisation models and algorithms, it still lacks a dispatching framework for HS facilities to integrate with the existing dispatching system of power grids. This study integrates a coordination control system (CCS) and a plant-level energy management system (PEMS) into the existing dispatching system and proposes the corresponding scheduling method to ensure the rationality, veracity, and timeliness of scheduling. The CCS generates power and thermal generation schedules in multi-time scales, while the PEMS operates as the bridge between the HS facilities and the CCS. Meanwhile, taking into account the actual scheduling requirements, the authors propose a downward spinning reserve capacity (DSRC) preservation method for the dispatch of CHP plants, develop multi-level coordination and progressive refinement strategy for schedules and apply the DSRC as a criterion to obtain the day-ahead, the rolling and the real-time schedules in sequence. Finally, the dispatch simulation results show that the newly proposed CHP dispatching framework can schedule the HS facilities in CHP plants effectively and achieve the desired effect of wind power accommodation.
A New Design Method for Frequency- Reconfigurable Antennas Using Multiple Tuning Components

Frequency-reconfigurable antennas seem a viable solution to achieve better performance and increased flexibility for integrated mobile phone antennas. Due to the lossy nature of many tunable components, the use of multiple combined tuning components in a single design seems attractive, as it can distribute the current over the components. However, many combinations of individual tuning component settings can result in an acceptable input match, while they will significantly vary in terms of radiation efficiency. It is challenging to distinguish between these radiating and nonradiating tuning component settings during the design procedure. In this paper, we propose a method to determine the component settings with the highest efficiency at a desired operating frequency. The method uses a single full-wave simulation, which is combined with circuit-level calculations. We discuss how to apply the method in detail and demonstrate its functionality with an inverted-L antenna sporting three tunable barium-strontium titanate capacitors. It is shown that the method can successfully predict tuning component settings for high antenna efficiency over a 1.4–2.8 GHz tuning band, with total efficiencies up to 35% and radiation efficiencies up to 50%. The method can easily be applied to any desired antenna geometry.
Multi-objective optimisation of steel moment frames subjected to blast

In recent decades, terrorist attacks have been increased all over the world. For this reason, the design of blast resistant structures is very crucial. On the other hand, for decades the optimum design of structures has been an interesting subject for structural engineers and researchers as it can provide cost and behavioural efficiencies. In the current research, the optimum design of steel moment frames under blast loading has been studied. Towards that end, first, a damage index is developed based on the maximum plastic strain in the members. Then, according to the damage index, a multi-objective optimisation methodology is proposed to minimise the structural weight and the damage index. The method utilises explicit nonlinear dynamic finite element analysis as the structural analysis method and NSGA-II optimisation algorithm as the optimisation technique. At the final point, based on the proposed method a framework is developed, and two numerical examples are studied. Results of this research show that the developed method is effective in achieving optimal designs with desired cost and damage.
Comprehensive Physics of Third Quadrant Characteristics for Accumulation- and Inversion-Channel 1.2-kV 4H-SiC MOSFETs

Detailed physics of the third quadrant electrical characteristics of 1.2-kV rated 4H-SiC accumulation (Acc) and inversion (Inv) channel MOSFETs, based on experimentally measured data and TCAD numerical simulations, are described in this paper for the first time. The power MOSFETs with various channel lengths (0.3, 0.5, 0.8, 1.1 <inline-formula> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula>) used in this paper were fabricated in a 6-in commercial foundry. Numerical simulations verified that there are two current paths in the third quadrant: 1) through the base region and 2) through the p-n body diode. This paper demonstrates that the Acc MOSFETs have a smaller third quadrant knee voltage (<inline-formula> <tex-math notation="LaTeX">${V}_{{\text {knee}}})$ </tex-math></inline-formula> of −1.2 V compared with −1.9 V for the Inv MOSFETs (at <inline-formula> <tex-math notation="LaTeX">${V}_{g} = {0}$ </tex-math></inline-formula> V and room temperature). Numerical simulations show that this difference is due to a smaller potential barrier for electron transport from the drain to the source in the base region for accumulation channel devices than inversion channel devices. Acc devices are shown to have a lower voltage drop in the third quadrant.
Trisection Bandpass Filters With All Mixed Couplings

In this letter, new patterns of symmetric trisection bandpass filters (BPFs) of two types with all mixed couplings are discussed. The condition under which the first-type filter with a central reflection-type resonator transforms into a delay line filter is considered. A second-type filter with a central through-type resonator becomes a quasi-elliptic filter under the same condition. As a result, the two transmission zeros are located equidistant regarding <inline-formula> <tex-math notation="LaTeX">$s= 0$ </tex-math></inline-formula> on the complex plane <inline-formula> <tex-math notation="LaTeX">$s= \sigma + j \Omega $ </tex-math></inline-formula>, <inline-formula> <tex-math notation="LaTeX">$\Omega = \omega /\omega _{0} - \omega _{0}/\omega $ </tex-math></inline-formula>)/FBW, mymargin for both types of filters, when this condition is fulfilled. A position of these transmission zeros with respect to <inline-formula> <tex-math notation="LaTeX">$s= 0$ </tex-math></inline-formula> is expressed in terms of the mixed coupling coefficients. Two compact microstrip trisection BPFs of different types with all mixed couplings were proposed, fabricated, and measured.
Adversarial Deep Learning Models with Multiple Adversaries

We develop an adversarial learning algorithm for supervised classification in general and Convolutional Neural Networks (CNN) in particular. The algorithm's objective is to produce small changes to the data distribution defined over positive and negative class labels so that the resulting data distribution is misclassified by the CNN. The theoretical goal is to determine a manipulating change on the input data that finds learner decision boundaries where many positive labels become negative labels. Then we propose a CNN which is secure against such unforeseen changes in data. The algorithm generates adversarial manipulations by formulating a multiplayer stochastic game targeting the classification performance of the CNN. The multiplayer stochastic game is expressed in terms of multiple two-player sequential games. Each game consists of interactions between two players—an intelligent adversary and the learner CNN—such that a player's payoff function increases with interactions. Following the convergence of a sequential noncooperative Stackelberg game, each two-player game is solved for the Nash equilibrium. The Nash equilibrium finds a pair of strategies (learner weights and evolutionary operations) from which there is no incentive for either learner or adversary to deviate. We then retrain the learner over all the adversarial manipulations generated by multiple players to propose a secure CNN which is robust to subsequent adversarial data manipulations. The adversarial data and corresponding CNN performance is evaluated on MNIST handwritten digits data. The results suggest that game theory and evolutionary algorithms are very effective in securing deep learning models against performance vulnerabilities simulated as attack scenarios from multiple adversaries.
TongueNet: A Precise and Fast Tongue Segmentation System Using U-Net with a Morphological Processing Layer

Automated tongue segmentation is a critical component of tongue diagnosis, especially in Traditional Chinese Medicine (TCM), where it has been practiced for thousands of years and is generally considered pain-free and non-invasive. Therefore, a more precise, fast, and robust tongue segmentation system to automatically segment tongue images from its raw format is necessary. Previous algorithms segmented the tongue in different ways, where the results are either inaccurate or time-consuming. Furthermore, none of them developed a dedicated, automatic segmentation system. In this paper, we proposed TongueNet, which is a precise and fast automatic tongue segmentation system. U-net is utilized as the segmentation backbone applying a small-scale image dataset. Besides this, a morphological layer is proposed in the latter stages of the architecture. The proposed system when applied to a tongue image dataset with 1000 images, achieved the highest Pixel Accuracy of 98.45% and consumed 0.267 s per picture on average, which outperformed conventional state-of-the-art tongue segmentation methods in both accuracy and speed. Extensive qualitative and quantitative experiments showed the robustness of the proposed system concerning different positions, poses, and shapes. The results indicate a promising step in achieving a fully automated tongue diagnosis system.
Redesign and upcycling – a solution for the competitiveness of smalland medium-sized enterprises in the clothing industry

The textile and clothing sector in Romania is one of the key industrial sectors. The sector accounts for providing employment to a large of labor force in the country. It creates employment for 137000 employees and it contributes for about 11% of the Romanian’s export revenues, at the second place after automotive industry, who held 40%. Despite being rated among the top European exporters of textiles, over the past years, the Romanian textile and clothing industry has become less competitive in the global marketplace [1]. There are many reasons for this, including the liberalizing policies of the EU and WTO, the low profitability as well as the intense competition from low cost producing countries. Romania’s competitive advantage in clothing industry, reported to the European one, is mainly due to low-cost labour force. The clothing industry is considered to be one of the most labour intensive industry that focuses on creating, designing, manufacturing, marketing, consuming, supplying chain, trading and many other components of clothing, and its accessories as a whole. Considering this, labour costs have a major impact of the competitiveness in this market and their continued growth has negatively influenced Romanian competitiveness. Due to the concurrent factors impacting the clothing industry, Romanian producers can no longer compete based on cost alone. Managers of the companies in clothing industries face major challenges to deal with the frequent problems that arise from ever changing operating conditions. They also have faced sophisticated strategic challenges that have to be addressed successfully if
Is Organizational Design a Human-Centered Design Practice?

In recent years design has had a renaissance in business and management research and practice. Several authors have discussed if management is a design practice and how far design ought to go to design behaviors. This article discusses, evaluates and explores organizational design as a human-centered design practice. Relevant theoretical concepts of organizational theory, design approaches and practices are discussed to evaluate gaps in management practices and potential opportunities for design practice. The study collected and analyzed data from two organizations. The researched revealed several propositions, which provide insights of the usefulness, appropriateness and value of a human-centered design practice to organizational design.
Regulatory mechanisms underlying the specification of the pupal-homologous stage in a hemimetabolous insect

Juvenile hormones and the genetic interaction between the transcription factors Krüppel homologue 1 (Kr-h1) and Broad (Br) regulate the transformation of insects from immature to adult forms in both types of metamorphosis (holometaboly with a pupal stage versus hemimetaboly with no pupal stage); however, knowledge about the exact instar in which this occurs is limited. Using the hemimetabolous cricket Gryllus bimaculatus (Gb), we demonstrate that a genetic interaction occurs among Gb′Kr-h1, Gb′Br and the adult-specifier transcription factor Gb′E93 from the sixth to final (eighth) nymphal instar. Gb′Kr-h1 and Gb′Br mRNAs were strongly expressed in the abdominal tissues of sixth instar nymphs, with precocious adult moults being induced by Gb′Kr-h1 or Gb′Br knockdown in the sixth instar. The depletion of Gb′Kr-h1 or Gb′Br upregulates Gb′E93 in the sixth instar. By contrast, Gb′E93 knockdown at the sixth instar prevents nymphs transitioning to adults, instead producing supernumerary nymphs. Gb′E93 also represses Gb′Kr-h1 and Gb′Br expression in the penultimate nymphal instar, demonstrating its important role in adult differentiation. Our results suggest that the regulatory mechanisms underlying the pupal transition in holometabolous insects are evolutionarily conserved in hemimetabolous G. bimaculatus, with the penultimate and final nymphal periods being equivalent to the pupal stage. This article is part of the theme issue ‘The evolution of complete metamorphosis’.
Immune gene regulation in the gut during metamorphosis in a holo- versus a hemimetabolous insect

During metamorphosis, holometabolous insects completely replace the larval gut and must control the microbiota to avoid septicaemia. Rapid induction of bactericidal activity in the insect gut at the onset of pupation has been described in numerous orders of the Holometabola and is best-studied in the Lepidoptera where it is under control of the 20-hydroxyecdysone (20E) moulting pathway. Here, using RNAseq, we compare the expression of immune effector genes in the gut during metamorphosis in a holometabolous (Galleria mellonella) and a hemimetabolous insect (Gryllus bimaculatus). We find that in G. mellonella, the expression of numerous immune effectors and the transcription factor GmEts are upregulated, with peak expression of three antimicrobial peptides (AMPs) and a lysozyme coinciding with delamination of the larval gut. By contrast, no such upregulation was detectable in the hemimetabolous Gr. bimaculatus. These findings support the idea that the upregulation of immune effectors at the onset of complete metamorphosis is an adaptive response, which controls the microbiota during gut replacement. This article is part of the theme issue ‘The evolution of complete metamorphosis’.
The Mediterranean was a Desert: A Voyage of the Glomar Challenger

The famous geological research ship Glomar Challenger was a radically new instrument that revolutionized earth science in the same sense that the cyclotron revolutionized nuclear physics, and its deep-sea drilling voyages, conducted from 1968 through 1983, were some of the great scientific adventures of our time. Beginning with the vessel's first cruises, which lent support to the idea of continental drift, the Challenger played a key part in the widely publicized plate-tectonics revolution and its challenge to more conventional theories. Here the leading oceanographer and earth scientist Kenneth Hs offers an intensely personal account of the experiences of the ship's diverse crews--the sailors, drillers, marine technicians, and scientists who braved not only the ocean's resistance to surrendering its secrets but also the difficulties of balky machinery, physical illness, close quarters, and all-too-human temperaments. But the intellectual rewards of the journeys also abounded, and Hs is the ideal writer to convey the excitement with which he and other crew scientists pursued them. The quintessential insider, he offers biographical sketches, humorous anecdotes, background information from the history of geology, and excerpts from the ship's daily operational report--all skillfully combined with a narrative history of the ship's explorations in the Pacific, Atlantic, and Indian oceans and the polar seas.