This paper presents the main results of the European H2020 WiMUST project, whose aim was the development of a system of cooperative autonomous underwater vehicles and autonomous surface vehicles for geotechnical surveying. In particular, insights on the overall robotic technologies and methodologies employed, ranging from the communications and navigation framework to the cooperative and coordinated

A novel solar power tower system that integrates with the cascade supercritical carbon dioxide Brayton-steam Rankine cycle is proposed to tackle the challenges of a simple supercritical carbon dioxide system in solar power systems. It provides a large storage capacity and can react to the fluctuation of solar radiation by adjusting the mass flow rate of molten salts in the receiver and heat exchanger

Concrete compression is complex. Yet, understanding this behavior is indispensable for design. There are three main factors that affect concrete compression results: the specimen size, shape, and friction at its ends. These factors affect the observed phenomena, and they affect each other. This paper aims to review the current knowledge on concrete compression and the effect of size, shape and friction

‘Que-Ti’ is an important component in typical Tibetan heritage timber buildings and it performs similar to corbel brackets connecting beam and column in modern structures. It transfers shear, compression and bending moment by slippage and deformation of components as well as limited joint rotation. A rigorous analytical model of ‘Que-Ti’ is needed for predicting the behavior of a timber structure under

Wood utility poles are widely applied in power transmission and telecommunication systems in Australia. Because of a variety of external influence factors, such as fungi, termite and environmental conditions, failure of poles due to the wood degradation with time is of common occurrence with high degree uncertainty. The pole failure may result in serious consequences including both economic and public

Simultaneous estimation of both the location and force history of an impact applied on a lattice truss core sandwich panel is inversely carried out utilizing velocity signals collected by means of a scanning laser Doppler vibrometer. The algorithm assumes that several impact forces are exerted concurrently on a number of specified locations on a panel, provided that the magnitude of all impact forces

Constructing a damage-sensitive factor (DSF) is one of the key steps in structural damage detection. In this paper, innovation series extracted from the auto-regressive conditional heteroscedasticity (ARCH) model are proposed to construct a DSF, which is defined as the standard deviation of innovation (SDI). A three-story shear building structure is used to demonstrate and verify the performance of

Precision guided projectiles (PGPs) experience severe shock loads during launch emanating from the propellant gases inside the barrel and the surrounding air. The complex flow environment that exists within the confined space of the barrel and at muzzle exit is greatly influenced by the supersonic speed of the projectile, the compressibility of the air, and the rapid state transition of the projectile

This paper deals with the identification of terrain that is crucial to trigger the damping in semi-active lower limb prosthesis. Objective: To identify level ground and ramp terrains using foot-to-ground angle (FGA) measurement. Methods: First, Instrumented shoe for FGA measurement was developed. Next, data collection from able-bodied (n=5) and amputee (n=1) participants was carried out. Finally, a

To overcome the large error caused by traditional ETC non-destructive detection, a novel method based on directly analysing the normalized capacitance value was proposed by using the finite element method described in the present study. In this article, the correlation between the normalized capacitance value and the measured object (the defect) size was summarized, and the influence of the geometric

Soil water content measurement is indispensable to precision agriculture. A novel soil water content measuring method based on frequency scanning is proposed in this research. The measuring system consists of a monopole antenna to emit and receive electromagnetic waves as well as a network analyzer. The soil equivalent circuit model is presented and its spectroscopy is obtained by comparing incident

Despite having a small footprint origin, COVID-19 has expanded its clutches to being a global pandemic with severe consequences threatening the survival of the human species. Despite international communities closing their corridors to reduce the exponential spread of the coronavirus. The need to study the patterns of transmission and spread gains utmost importance at the grass-root level of the social

A sign language recognition (SLR) system has been broadly used by deaf individuals as a communicative tool. Progress of SLR systems paves the way for the development of Human–computer interaction (HCI) since sign language is the most structured form, and every movement has a specific meaning. In this paper, a wearable low-cost device based on surface electromyography (sEMG) and Inertial Measurement

Miniature fixed-point blackbodies (MFPBs) can realize the on-orbit multipoint temperature calibration through the known characteristic temperature. This ability is important for improving the precision and life span of earth observation systems. For acquisition of characteristic temperature, numerical simulation has lower cost and test condition requirements. However, ordinary numerical models can’t

The processes of diffusion and reaction play essential roles in numerous system dynamics. Consequently, the solutions of reaction–diffusion equations have gained much attention because of not only their occurrence in many fields of science but also the existence of important properties and information in the solutions. However, despite the wide range of numerical methods explored for approximating

In this paper, some new nonlinear fractional partial differential equations (PDEs) have been considered.Three models are including the space-time fractional-order Boussinesq equation, space-time (2 + 1)-dimensional breaking soliton equations, and space-time fractional-order SRLW equation describe the behavior of these equations in the diverse applications. Meanwhile, the fractional derivatives in the

In this paper, a numerical technique for a general form of nonlinear fractional-order differential equations with a linear functional argument using Chebyshev series is presented. The proposed equation with its linear functional argument represents a general form of delay and advanced nonlinear fractional-order differential equations. The spectral collocation method is extended to study this problem

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

SARS-CoV-2 infection is initiated by virus binding to ACE2 cell surface receptors1–4, followed by fusion of virus and cell membranes to release the virus genome into the cell. Both receptor binding and membrane fusion activities are mediated by the virus Spike glycoprotein, S5–7. As with other class I membrane fusion proteins, S is post-translationally cleaved, in this case by furin, into S1 and S2

A new type of peptide produces pain so intense that sometimes even morphine cannot quell it.

Advisory groups around the world release guidance to prioritize healthcare workers and others.

We have not met any of the biodiversity targets agreed in 2010 — but there are hopeful signs to build on. Plus, how COVID-19 can damage the brain and a visually sumptuous tour of the latest dinosaur discoveries.

In the era of big data, Internet search data have become an effective data source for solving social and economic problems, such as tourist arrival prediction. The Internet searches often predate and foretell the actual travels. It is very meaningful to predict the tourist arrivals in a destination based on the Internet search data. Considering the coexistence of linear and nonlinear features of daily

With the increasing openness of smart grids, a large quantity of power terminals will be widely applied in systems of smart grids by various access modes (wired, wireless, satellite). In order to ensure the integrity and confidentiality of the data and the security of the communications between power terminals and the smart grid intranet, a lightweight security authentication and key agreement scheme

In this article, we propose, investigate, and analyze a novel designed two guided modes regions ring-core photonic crystal fiber (PCF) with relatively greater effective refractive index separation and also high isolation value which can be negligible the crosstalk among the guided channels. The designed PCF can be well supported up to 76 orbital angular momentum (OAM) modes and 6 linear polarization

The growing imbalance in regional innovation development has become an urgent issue in China’s strategy to build an innovative country. To enrich the regional innovation capacity evaluation system, scientifically assess regional innovation capacity, and explore available pathways to improve regional innovation capacity, this paper introduces a multiattribute decision-making method for evaluating regional

Aiming at the characteristics of the nonlinear changes in the internal corrosion rate in gas pipelines, and artificial neural networks easily fall into a local optimum. This paper proposes a model that combines a principal component analysis (PCA) algorithm and a dynamic fuzzy neural network (D-FNN) to address the problems above. The principal component analysis algorithm is used for dimensional reduction

Many collaborative robots use strain-wave-type transmissions due to their desirable characteristics of high torque capacity and low weight. However, their inherent complex and nonlinear behavior introduces significant errors and uncertainties in the robot dynamics calibration, resulting in decreased performance for motion and force control tasks and lead-through programming applications. This paper

The three-dimensional discrete element method (DEM) was employed to investigate the combined effects of inherent and stress-induced anisotropy of granular materials. The particles were modeled following real particle shapes. Both isotropic and inherently anisotropic specimens were prepared, and then true triaxial numerical tests were conducted using different intermediate principle stress ratios (b)

In the present paper, a new trigonometric two-variable shear deformation beam nonlocal strain gradient theory is developed and applied to investigate the combined effects of nonlocal stress and strain gradient on the bending, buckling and free vibration analysis of nanobeams. The model introduces a nonlocal stress field parameter and a length scale parameter to capture the size effect. The governing

Wave propagation simulation in a multi-hybrid nanocomposite (MHC)-reinforced doubly curved open shell covered with piezoelectric actuator is examined for the first time. The third-order shear deformation theory (third-order SDT) is applied to formulate the stress–strain relations. Rule of the mixture and modified Halpin–Tsai model are engaged to provide the effective material constants of the MHC-reinforced

Ventures of manufacturing multinationals into overseas markets are on the rise despite the recent rising protectionism. The optimal selection of international human resources is one of the critical success factors contributing to cross-border task performance and manufacturing efficiency. This paper addresses the expatriate selection problem by presenting an integrated two-stage optimization approach

In this paper we study a proportionate flow shop of batching machines with release dates and a fixed number \(m \ge 2\) of machines. The scheduling problem has so far barely received any attention in the literature, but recently its importance has increased significantly, due to applications in the industrial scaling of modern bio-medicine production processes. We show that for any fixed number of

The extensive application of titanium alloys is delimited as their erosion wear properties deteriorate when exposed to erosive and harsh environments. The present research investigates the effects of TiN additions (2, 4, and 6 vol.%) on the Ti-6Al-4V alloy prepared by spark plasma sintering technique. Erosion wear behaviour of the composites was investigated by high-velocity solid particle erosion

The total hip arthroplasty (THA) is considered as one of the most successful orthopedic surgeries, through which the damaged hip joint is replaced with hip joint prosthesis. Besides, automatic nano-finishing of femoral head is of great importance in improving tribological, biological, and metallurgical properties of hip joint implants and increases the productivity of manufacturing process. In the

Undetected tool wear during drilling of woven composites can cause laminate damage and fiber pull-out and fuzzing, causing subsurface damage. This diminishes the life of the produced part under fatigue loads. Thus, the producing of proper and reliable holes in woven composites requires accurate monitoring of the cutting tool wear level to safeguard the machined parts and increase process productivity

Micro grooves with a semicircular cross-section of tens of microns in radius on metal foils have posed a challenge for machining. This paper proposed stepwise manipulating process parameters in wire electrochemical micromachining (WECMM) to improve the profile accuracy of micro grooves with a semicircular cross-section via evenly distributing the machining gap. Firstly, a two-dimensional model of the

In this paper, a state-of-the-art review on cutting tool technology in machining of Ni-based superalloys is presented to better understand the current status and to identify future directions of research and development of cutting tool technologies. First, past review articles related to the machining of Ni-based superalloys are summarized. Then machinability of superalloys is introduced, together

This paper explores the use of discrete event simulation (DES) for decision making in real time based on the potential for data streamed from production line sensors. Technological innovations for data collection and an increasingly competitive global market have led to an increase in the application of discrete event simulation by manufacturing companies in recent years. Scenario analysis and optimisation

Nowadays, COVID-19 also known as novel coronavirus has become a global pandemic by causing severe respiratory tract infections in humans without any definite treatment or vaccine. Therefore, disease control measures include slowing down or averting the transfer of this viral infection from person to person. Continuous efforts are carried out to avoid the transmission of this disease to frontline healthcare

In this paper a residue-to-binary converter for the 7-modulus set {2n–5–1, 2n–3–1, 2n–2+1, 2n–1–1, 2n–1+1, 2n, 2n+1} for n even is presented, which is an improved version of a reverse converter presented recently. The proposed converter needs less hardware resources ranging from 52.9% to 66.9%, conversion time of 68–70.7% and power dissipation of 47–63% of those needed for an earlier described converter

At present, how to evaluate the impact of product design changes in product development process has been a problem to be solved. The research on product design changes has gradually shifted from the component level to the product feature level. Therefore, the components are divided into feature level, and a product feature network is built to analyse the propagation of changes. Because it is not unique

Mechanistic studies of anaerobic gut bacteria have been hindered by the lack of a fluorescent protein system to track and visualize proteins and dynamic cellular processes in actively growing bacteria. Although underappreciated, many gut “anaerobes” are able to respire using oxygen as the terminal electron acceptor. The oxygen continually released from gut epithelial cells creates an oxygen gradient

Integrating a long-established soil erosion model with Intergovernmental Panel on Climate Change (IPCC) scenarios, Borrelli et al. (1) set out to meet the needs of policymakers and earth-system modelers to better understand the future of soil erosion this century. Policymakers need this insight because of the constraints erosion places on achievement of multiple sustainable development goals including

Edilson Consuelo de Oliveira has regained his sense of taste and smell, so he has finally been able to enjoy a plate of pirapitinga, his favorite fish in all the Amazon. Before contracting coronavirus disease 2019 (COVID-19), Edilson had been in lockdown on a small farm outside of Rio Branco, the capital of Acre state in Brazil, but in early June a nephew came to visit from the city, bringing a dry

Grain growth under shear annealing is crucial for controlling the properties of polycrystalline materials. However, their microscopic kinetics are not well understood because individual atomic trajectories are difficult to track. Here, we study grain growth with single-particle kinetics in colloidal polycrystals using video microscopy. Rich grain-growth phenomena are revealed in three shear regimes

In the real world, complex dynamic scenes often arise from the composition of simpler parts. The visual system exploits this structure by hierarchically decomposing dynamic scenes: When we see a person walking on a train or an animal running in a herd, we recognize the individual’s movement as nested within a reference frame that is, itself, moving. Despite its ubiquity, surprisingly little is understood

The mechanisms underlying sex determination are astonishingly plastic. Particularly the triggers for the molecular machinery, which recalls either the male or female developmental program, are highly variable and have evolved independently and repeatedly. Fish show a huge variety of sex determination systems, including both genetic and environmental triggers. The advent of sex chromosomes is assumed

Software refactoring is a commonly accepted means of improving the software quality without affecting its observable behaviour. It has gained significant attention from both academia and software industry. Therefore, numerous approaches have been proposed to automate refactoring that consider software quality maximization as their prime objective. However, this objective is not enough to generate good

Piezoelectric vibration energy harvesting has attracted considerable attention because of its prospects in self-powered electronic applications. There are a many low-velocity waters in nature, such as rivers, seas and oceans, which contain abundant hydrokinetic energy. In this paper, an optimal geometric piezoelectric beam combining magnetic excitation is identified and applied to a vortex-induced

Extracellular polymeric substances (EPS) occur naturally and widely on the surface of microbial cells; their reducibility may play a crucial role in graphene oxide reduction. In this work, the conversion of graphene oxide (GO) into reduction graphene oxide (rGO) with EPS (extracted from Bacillus sp.NT 10) as green reductant had been conducted to explore their potential application for graphene preparation

A higher number of highway construction projects are experiencing delays in their scheduled completion time, and this situation, in turn, leads to overrun in the schedule as well as cost. This paper mainly categorizes the causes of time overrun and provides a mathematical model for predicting the time overrun percentage, using highway projects in Northern India as a case study. A survey of randomly

For the time being, the creation of surface nano-structures has become an important technological process which plays a paramount role in the electronic devices, as it has a very remarkable feature that they are used in etching without using chemicals. Irradiation of silicon oxide single crystal with slow highly charged ions can produce surface nano-hillocks. The formation mechanism of the created

In the present study, long-term multi-stress aging performance of silicone-based polymeric insulators was investigated for possible use on high-voltage alternating current transmission lines in Pakistan. One neat sample of high-temperature-vulcanized silicone rubber and four silica and alumina trihydrate filled hybrid composites were studied for 5000 h under accelerated multi-stress aging simulating

In science news around the world, President Donald Trump admits he knew in February that the coronavirus that causes COVID-19 was "deadly," even as he publicly called the disease no worse than the seasonal flu. Scientists study the long-term health consequences of smoke from record wildfires on the U.S. West Coast. The virus that causes African swine fever, deadly to pigs, is discovered in Germany

Several studies about to start will explore whether near-infrared (NIR) light can improve symptoms of Parkinson's disease—including a study in France in which a fiber optic cable implanted in patients' brains will deliver NIR directly to the substantia nigra, a region that degenerates in Parkinson's disease. Animal models and small tests in people have suggested benefits, but some mainstream Parkinson's

A massive new study of DNA sequences from Viking Age burials around Europe presents the story of the Vikings written in genes. The results, published this week in Nature, trace how the Vikings radiated across Europe from their Scandinavian homeland, and how people with roots elsewhere also took up Viking ways, making "Viking" a job description, not a matter of heredity. Researchers gathered human remains