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• This manuscript proposed a unique mirror symmetric µ-near-zero wide band-stop metamaterial shield for EMI shielding applications in the C- and X-band. • The proposed design intends to employ a shared metamaterial structure to serve two distinct microwave bands with extended shielding bandwidth. • The wide band-stop characteristics as well as frequency and bandwidth modulation flexibility make the structure unique for EMI shielding applications. • The simple shorting metallic strip in the proposed structure can control the shielding spectrum from C-band to X-band with an outstanding band-stop enhancement capability of 170.63%, which significantly outperforms the existing state-of-the-art metamaterials. • The proposed metamaterial prototypes are fabricated and experimentally verified their shielding performance and show promising results for wideband EMI shielding applications. In this paper, a µ-near-zero wide band-stop metamaterial (MM) shield is conducted for electromagnetic interference (EMI) shielding purposes in the C- and X-band. The proposed design intends to employ a shared MM structure to serve two distinct microwave bands with extended shielding bandwidth. The proposed structure consists of metal strip coupled four identical quartiles based unique mirror symmetric resonator and designed on a low-loss Rogers 5880 substrate within a compact physical dimension of 7.5 mm × 7.5 mm × 1.575 mm. The speciality of the proposed MM is its wide band-stop functionality with maximum shielding bandwidth and effectiveness of 4.33 GHz and 66.6 dB, respectively. Moreover, four shorting metal strips among adjacent quartiles can control the shielding spectrum from C-band to X-band with an outstanding band-stop enhancement capability of 170.63 %, which significantly outperforms the existing MMs. Therefore, the proposed MM structure can be utilized for two distinct wide frequency spectrums shielding by introducing simple shorting metallic strips. The electromagnetic radiation shielding phenomena are also explained using surface current and electric and magnetic field distribution. The proposed MM prototypes are fabricated and experimentally verified with numerical results. The promising shielding performance of the developed MM demonstrates the potentiality for shielding undesired electromagnetic radiation. [ABSTRACT FROM AUTHOR]

Low frequency oscillation (LFO) is one of the major concerns for reliable operation of the power system. This LFO occurs due to the failure of the rotor to supply sufficient damping torque to compensate the imbalance between mechanical input and electrical output. Hence, in this paper, we adopt a third generation flexible AC transmission system (FACTS) device named generalized unified power flow controller (GUPFC) based damping controller in order to investigate its effect for mitigating LFO for an single machine infinite bus (SMIB) system. To find an effective damping controller-optimizer pair, we integrate proportional–integral (PI) or lead–lag as a controller and grey wolf optimizer (GWO), differential evolution (DE), particle swarm optimization (PSO), whale optimization algorithm (WOA), and chaotic whale optimization algorithm (CWOA) as an optimizer. Later, we investigate the performances for the above mentioned controller-optimizer pairs through time domain simulation, eigenvalue analysis, nyquist stability test, and quantitative analysis. Moreover, we carry out two non-parametric statistical tests named as one sample Kolmogorov–Smirnov (KS) test and paired sample t − t e s t to identify statistical distribution as well as uniqueness of our optimization algorithms. Our analyses reveal that the GWO tuned lead–lag controller surpasses all other controller-optimizer combinations. • Adoption of third generation FACTs device such as GUPFC for mitigating LFO. • Identification of the most suitable GUPFC control input using controllability and residue indices. • Selection of efficient damping controller-optimizer pair from ten different combinations. • Demonstration of effectiveness for these combination through Eigen value analysis, time-domain analysis, quantitative analysis, and non-parametric statistical test. [ABSTRACT FROM AUTHOR]

• Novel N-doped green-emitting carbon dots with high QYs (17.36%–48.4%) were synthesized for multifaceted application. • N-GCDs exhibited strict solvent polarity-dependent switchability (solvatochromism). • Solvatochromism technique was utilized to detect moisture content in acetone and THF with LOD 0.37% and 0.38%, respectively. • N-GCDs were utilized to detect pH in the range of 3.8–6.2 with good linear relationship (R2 = 0.99). • Multicolor-emissive N-GCD/polymer films were prepared demonstrating the application of N-GCDs for solid-state lighting. Novel N-doped green-emitting carbon dots (N-GCDs) that were responsive to various external stimuli and had high quantum yields (QYs) for multifaceted applications were synthesized from β-resorcylic acid and ethylenediamine using a hydrothermal process followed by a reflux method. The QYs of the N-GCDs were in the range of 17.36%–48.4% and were associated with different photoluminescent color emission in different solvents. Interestingly, the as-synthesized N-GCDs exhibited strict solvent polarity-dependent switchability (solvatochromism) and multicolor excitation-wavelength-independent emission in different solvents. Sensing of an analyte based on the switching of the photoluminescence (PL) emission maxima (λ max) is always preferred over that based on fluorescence quenching to avoid complexity and confusion regarding the initial fluorescence intensity (I 0) and thus make the sensing process simple, rapid, ordered, and reliable. The N-GCDs exhibited blue emission in low-polarity organic solvents, but with the increase of the trace water content in the system, the PL emission peak gradually shifted to a higher wavelength (bathochromic shift) at a single-wavelength excitation. Thus, the N-GCDs are sensitive visual probes for the fluorescence detection of the trace water content in organic solvents without sophisticated processes. They also indicate the pH-response behavior. When the pH decreased from 7.6 to 2.4, the fluorescence emission intensity decreased, with a particularly good linear relationship (R2 = 0.990) in the range of 3.8–6.2. Moreover, the polarity-dependent-emission property was observed in the solid state polymer matrices. Multicolor-emissive N-GCD/polymer films were prepared by integrating N-GCDs with the polymer matrices of different polarity, demonstrating the application of carbon dots for solid-state lighting. [ABSTRACT FROM AUTHOR]

Peer-to-peer energy trading allows smart grid-connected parties to trade renewable energy among each other. It is widely considered as a scheme to mitigate the supply–demand imbalances during peak-hour. However, the main challenge of such a scheme is the lack of secure, efficient, and transparent systems that foster economic incentives for users. This paper proposes a novel system that combines cooperative game theory and blockchain technology to stimulate users to maximize their profit and trade energy securely. In our model, users can store renewable energy credits as assets in the blockchain and trade them with others. We also develop a modified version of Proof of Energy Generation (PoEG) by including distribution line loss as a consensus mechanism among blockchain energy trading members. Then, we propose a coalition formation algorithm based on PoEG protocol and optimization technique to determine the winning coalition as block miners. The system is validated through comprehensive theoretical analysis and simulation experiments utilizing a standard IEEE 14-bus system and a real-life dataset (Ausgrid). Also, the developed model is implemented on the Avalanche blockchain platform. The test results show that the proposed scheme improves prosumers' financial benefits by 6.5% in terms of energy savings compared to the baseline model. The experiments demonstrate the effectiveness, capabilities, and robustness of the proposed system. • Proposing a blockchain and cooperative game theory-based P2P energy trading system. • Developing a coalition formation algorithm based on PoEG to determine block miners. • Validating the model using comprehensive theoretical analysis and experiments. • Utilizing a standard IEEE 14-bus system and the Ausgrid Dataset for the experiments. • Implementing the model using the Avalanche blockchain platform. [ABSTRACT FROM AUTHOR]

Abstract Carbon dots (CDs) responsive to external stimuli that cause changes in their optical properties are in high demand. Herein, we present a microwave synthesis of highly fluorescent CDs derived for the first time from β-resorcylic acid (henceforth referred as R-CDs) in sulfuric acid (H 2 SO 4) medium. Interestingly, the as-synthesized R-CDs showed tunable optical properties with three distinguishable colors (green/blue/blue-violet) depending on pH under UV irradiation. Spectral analyses and mechanistic studies revealed that the fluorescence switch is due to the deprotonation of the oxygenous surface functionalities in the R-CDs. The pH-dependent color switchability was tested in a number of cycles under UV light by adding 0.1 (M) HCl and NaOH. Although several mechanisms involving the complex photoluminescence of CDs have been reported, we propose here that the photoluminescence behavior of the CDs can be tuned by deprotonation of the oxygenous surface functionalities. Moreover, these R-CDs can be used as a potential visual indicator of three different pH ranges, and as highly selective and sensitive sensing medium for Fe3+ ions. The limit of detection was calculated to be 0.43 μM. Graphical abstract Image 1 Highlights • Carbon dots (R-CDs) were synthesized from β-resorcylic acid using microwave irradiation. • R-CDs showed pH dependent tunable optical properties under UV irradiation. • Two prototropic equilibria (Carboxylic acid ↔ carboxylate and phenol ↔ phenolate) controls photophysical properties. • R-CDs showed high selectivity and sensitivity towards Fe3+ metal ions. [ABSTRACT FROM AUTHOR]

Water pollution is a worldwide concern that has growing severe in developed and developing nations. Increasing groundwater pollution threatening both the physical and environmental health of billions of people as well as economic progress. Consequently, hydrogeochemistry, water quality and potential health risk assessment is crucial for water resource management. The study area comprises Jamuna Floodplain (Holocene deposit) area in the west and the Madhupur tract (Pleistocene deposit) area in the eastern part. Total 39 groundwater samples were collected from the study area and were analyzed for physicochemical parameters, hydrogeochemical, trace metals, and isotopic composition. The water types are mainly Ca–HCO 3 - to Na–HCO 3 - types. The isotopic compositions (δ18O‰ and δ2H‰) analysis traces the recent recharge in Floodplain area from rainwater and no recent recharge in Madhupur tract. The concentration of NO 3 −, As, Cr, Ni, Pb, Fe, and Mn in shallow and intermediate aquifer at the Floodplain area exceed the WHO-2011 permissible limit and is lower at deep Holocene and Madhupur tract aquifer. The integrated weighted water quality index (IWQI) exposed groundwater from shallow and intermediate aquifer are unsuitable for drinking and deep Holocene aquifer and Madhupur tract are suitable for drinking purposes. PCA analysis confirmed that anthropogenic activity is dominant in shallow and intermediate aquifers. The non-carcinogenic and carcinogenic risk for adults and children is due to oral and dermal exposure. The non-carcinogenic risk evaluation revealed that the mean hazard index (HI) values range from 0.009742 to 16.37 for adults and 0.0124–20.83 for children, respectively, and most groundwater samples from shallow and intermediate aquifers exceed the permissible limit (HI>1). The carcinogenic risk ranges from 2.71 × 10−6-0.014 for adults and 3.44 × 10−6-0.017 for children via oral consumption and 7.09 × 10−11-1.18 × 10−6 for adults and 1.25 × 10−10-2.09 × 10−6 for children via dermal exposure. Spatial distribution shows the presence of trace metal and associated health risk is high in shallow and intermediate aquifer (Holocene) than in the deep (Holocene) Madhupur tract (Pleistocene). The study implies that effective water management will ensure safe drinking water for the future generation of people. [Display omitted] • Estimates the amount of anthropogenic contaminant and trace metals. • IWQI, HPI, HEI and C d determines the groundwater from shallow and intermediate aquifers is unsuitable for drinking. • Carcinogenic and non-carcinogenic risks are higher in shallow and intermediate aquifers. [ABSTRACT FROM AUTHOR]

Mango (Mangifera indica) is perhaps the most notable sound natural product, however short-lived. A few synthetic compounds like calcium carbide, pesticides, formalin and calcium-based arrangements have been utilizing for its protection, notwithstanding, those synthetic compounds are perilous for our human wellbeing. Besides, mango strip is a food-handling by-product that is discarded since it isn't economically reasonable. For this study, the nutritional, antibacterial, and antioxidant properties of peels from two mango cultivars (Amrapali, and BARI-11) were analyzed with four doses (0.5, 1.0, 1.5, and 2 kGy) of gamma irradiation. The impacts of radiation on storage quality and life span of usability were likewise investigated. Mango peels were found to have many phytochemicals. Be that as it may, radiation altogether impacted tested parameters like fat, protein, carb, fiber, sugar, energy, soluble solids, etc. in both of the mango peels. On the other hand, the peel samples showed 50% DPPH scavenging activity at varied dosages. Moreover, samples exposed to 1.5 kGy of radiation showed higher antioxidant activity. At a radiation dose of 1.5 kGy, amrapali peel proved to be less hazardous to brine shrimp lethality assay than other samples. The widest inhibitory zones against Pseudomonas sp. were obtained at a dosage of 150 µg/disc. After two weeks of storage, the 1.5 kGy radiation dosage left the mangoes' texture firm, indicating that it was extending the fruit's shelf life by greatly reducing the microbial attack. Thus mangoes could be preserved using radiation without significantly affecting their nutritional value. [ABSTRACT FROM AUTHOR]

The present experiment was conducted to explicate the genotoxic effects of profenofos, an organophosphate insecticide, on the erythrocytes of silver barb ( Barbonymus gonionotus ). Silver barb were exposed to a solution of 10% and 50% of lethal concentrations (LC 50 ) of profenofos as sub-lethal concentrations at different days (1, 7, 15, and 30 d), along with a control (0% profenofos). Subsequent recovery patterns were assessed allowing the fish exposed to profenofos free water for the same period that they were exposed to profenofos. Our results revealed that with the progression of time and concentration, fish exposed to profenofos showed significantly (p < .05) higher level of erythrocytic nuclear abnormalities (ENA) such as micronuclei, bi-nuclei, degenerated nuclei, notched nuclei, nuclear bridge and nuclear buds, as well as erythrocytic cellular abnormalities (ECA) such as echinocytic, elongated, fusion, spindle, tear-drop and twin shaped cells. After exposure, the silver barb recovered spontaneously, and the abnormal erythrocytic parameters were normalized with a concentration- and duration-dependent fashion. Therefore, these abnormalities and their recovery can be used to assess the toxic levels of pesticides on aquatic organisms. There is great potential to use this technique as in vivo to predict susceptibility of aquatic animals to environmental pollution. [ABSTRACT FROM AUTHOR]

Comfort could be one of the major factors influencing demand for public transit systems across income groups. Those in the high-income group, typically car owners, value comfort more than those in the traditionally captive low-income group. This paper examines the heterogenous effect of crowding on mode choice and the subsequent demand for mass rapid transit (MRT) system across income groups using stated-preference data collected from Dhaka, Bangladesh. The crowding variable was incorporated into mixed logit models as a Bureau of Public Roads (BPR)-type function, establishing non-linear sensitivity of different income groups to the effect of crowding on mode choice. We then estimate equilibrium passenger flows for different income groups for multiple scenarios based on varying levels of fares and capacity under the stochastic user equilibrium (SUE) condition. The consumer surplus, revenue, and total surplus associated with each scenario were calculated. The findings show that fares that maximize social welfare are not equitable as they result in very low MRT demand among the low-income group. Meanwhile, higher fares result in greater demand for MRT among the high-income group, improved social welfare, and less total car use. These results highlight the trade-off between an equitable public transport system and environmental sustainability. [ABSTRACT FROM AUTHOR]

[Display omitted] • Polychromatic CQDs were prepared based on regulated acidic strength. • Facile wet chemistry based method produces tricolor polyaromatic-polyphenolic CQDs. • Multicolor photostable luminous CQDs promises intense full color cellular imaging. • CQDs had NIR-responsive high photothermal efficiency (32.65%) with good stability. • CQDs were utilized as favorable photothermal agent for efficient bactericidal activity. A strategy for the processing of photoluminescence emission tunable multicolor carbon quantum dots has been adopted based on the controllable acidic strength [different ratio mixtures of sulfuric and phosphoric acids (S:P)] using a single polyphenolic precursor. 1,3,5-trihydroxybenzene, a three-fold symmetric (C 3h symmetry) triangulogen bearing –OH group at the meta position, was judiciously chosen to undergo dehydration facilitated condensation and carbonization suitably via a tri-molecular reaction route in a dehydrating acid medium. Polyaromatic-polyphenolic CQDs with multicolor emissions [blue (B-CQDs), green (G-CQDs), and yellow (Y-CQDs)] could be rapidly obtained through a facile wet chemistry-based thermal heating process. The mechanism of regulated bottom-up growth of CQD particles involved tri-molecular ring cyclization. These multicolor luminous CQD probes enabled intense multicolor cellular imaging throughout the entire visible range because of their good biocompatibility, photostability, and effective intracellular distribution. Moreover, Y-CQDs with larger polyaromatic sp2 domains and higher oxidized surfaces exhibited a high photothermal conversion efficiency (PCE ∼ 32.6 ± 1 %) and thus exhibited remarkable NIR-light responsive photothermal bactericidal activity. Our results demonstrate that hyperthermia-induced bactericidal activity is due to the elevated reactive oxygen species (ROS) amplification and membrane damage of Bacillus subtilis. This study provides a potential alternative for the multicolor imaging guided CQDs-based phototheranostic. [ABSTRACT FROM AUTHOR]

Ethnapharmacological relevance Stephania japonica is a common plant, widely distributed in all over Bangladesh. Traditionally, this plant is considered as one of the important ingredients in treatment of a variety of ailments including inflammation, pain, rheumatism, cancer, bone fracture, fever etc. However, the scientific reports regarding the antinociceptive effect of this plant are very limited. This study evaluated the antinociceptive effect of methanolic extract of S. japonica (MESJ) leaves. Materials and methods The antinociceptive effect of MESJ was investigated using both heat- and chemical-induced nociceptive models such as hot plate, tail immersion, acetic acid-induced writhing, formalin and glutamate tests at the doses of 50, 100 and 200 mg/kg. Morphine (5 mg/kg) and diclofenac sodium (10 mg/kg) were used as reference drugs in thermal and chemical models, respectively. Moreover, naloxone (2 mg/kg) was used in the thermal models to justify the possible role of the opioid receptors. Results MESJ produced a significant and dose-dependent increase in the hot plate and tail immersion latencies which were reversed by the treatment with naloxone, suggests the possible involvement of opioid receptors in this activity. Moreover, MESJ inhibited acetic acid-induced writhing, formalin and glutamate-induced lickings in a dose-dependent manner. In parallel, the reference drugs also produced desired antinociceptive effects in this study. Conclusion These results strongly support the antinociceptive activity of the leaves of Stephania japonica and rationalize the traditional use of the leaves in treatment of different painful conditions. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Physalis alkekengi is an edible herb whose fruit and calyx are traditionally used to treat a wide range of diseases including inflammation, toothache, and rheumatism. However, the effects of Physalis alkekengi fruit along with its calyx (PAF) on neuroinflammation and inflammatory pain behavior have not been reported yet. Aim of the study This study evaluated the anti-inflammatory effect of PAF on lipopolysaccharide (LPS)-induced neuroinflammation and several in vivo model of inflammatory pain in mice. Materials and methods Here, first we studied the effects of PAF fractions on the production of pro-inflammatory mediators in LPS-treated BV2 microglial cells using enzyme-linked immunosorbent assay. The translocation of nuclear factor-kappa B (NF-κB) and the involvements of Akt and mitogen-activated protein (MAP) kinases in ethyl acetate fraction of PAF (PAF-EA)-mediated anti-inflammatory effect were measured using Western blotting. In in vivo experiments, the efficacy of PAF-EA was evaluated at the doses of 100 and 200 mg/kg using several chemical-induced models of inflammatory pain such as acetic acid-induced writhing, formalin-induced paw licking and edema. Results We found that compared to other fractions, the PAF-EA more potently inhibited the LPS-induced generation of nitric oxide, tumor necrosis factor-α, interleukin-6 and reactive oxygen species. It also inhibited LPS-induced nuclear translocation of NF-κB. These actions of EA fraction were found to be associated with a disruption of Akt and MAP kinases signaling pathways. The EA fraction also significantly inhibited acetic acid-induced writhing, formalin-induced licking time and edema in mice. Conclusions Our findings support the ethnopharmacological use of P. alkekengi fruit along with its calyx as an anti-inflammatory agent and suggest that the EA fraction of PAF may serve as a potential candidate to treat different neurological disorders and pain associated with inflammation. [ABSTRACT FROM AUTHOR]

The objective of this paper is to investigate the attributes of walkable environments from the perspective of seniors in the Island of Montreal in Quebec, Canada. The research is based on a combination of statistical analysis of travel diary data and field work to conduct walkability audits. The approach follows a sequence of logical steps. The first step involves the estimation of a travel behavior model walking by seniors (people 65 years or older). The results of this model, in combination with cluster analysis, are used to identify sites where the model systematically under- or over-predicts walking. Subsequently, sites are targeted for walkability audits. It then becomes possible to assess the presence or absence of attributes of built environments where walking is more or less common than other factors would predict. A walkability audit of 403 street segments was used to proof the concept in this paper. The audited items were summarized in contingency tables and tested with the chi-squared test of independence to identify streetscape elements that correlate with walking for transportation. [ABSTRACT FROM AUTHOR]

Short-term forecasting of traffic characteristics, such as traffic flow, speed, travel time, and queue length, has gained considerable attention from transportation researchers and practitioners over past three decades. While past studies primarily focused on traffic characteristics on freeways or urban arterials this study places particular emphasis on modeling the crossing time over one of the busiest US–Canada bridges, the Ambassador Bridge. Using a month-long volume data from Remote Traffic Microwave Sensors and a yearlong Global Positioning System data for crossing time two sets of ANN models are designed, trained, and validated to perform short-term predictions of (1) the volume of trucks crossing the Ambassador Bridge and (2) the time it takes for the trucks to cross the bridge from one side to the other. The prediction of crossing time is contingent on truck volume on the bridge and therefore separate ANN models were trained to predict the volume. A multilayer feedforward neural network with backpropagation approach was used to train the ANN models. Predicted crossing times from the ANNs have a high correlation with the observed values. Evaluation indicators further confirmed the high forecasting capability of the trained ANN models. The ANN models from this study could be used for short-term forecasting of crossing time that would support operations of ITS technologies. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Polyalthia longifolia var. pendula is a very popular herb in Bangladesh due to its traditional uses in treatment of rheumatism, bone fracture and gastric ulcer. The present study was conducted to investigate the antinociceptive activity of ethanol extract of P. longifolia (EEPL) bark. Materials and methods Hot plate and tail immersion tests, acetic acid-induced writhing test, glutamate and formalin-induced paw licking tests in mice were employed in this study. In all the experiments EEPL was administered orally at the doses of 50, 100 and 200 mg/kg body weight. To investigate the possible participation of opioid system in EEPL-mediated effects, naloxone was used to antagonize the action. Results EEPL showed a significant antinociceptive activity against both heat and chemical-induced nociception. The effects were dose-dependent and significant at the doses of 100 and 200 mg/kg of EEPL. Besides, pretreatment with naloxone caused significant inhibition of the antinociceptive activity induced by EEPL, revealing the possible involvement of the opioid receptors. Conclusion These results indicate the antinociceptive activity of the bark of P. longifolia and support the ethnomedical use of this plant in treatment of different painful conditions. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Hedyotis corymbosa (Linn.) Lam. is a small herb commonly called as khetpapra, traditionally used to treat a wide range of diseases including abdominal pain, arthritis and inflammation. This study was conducted to evaluate the antinociceptive effect of ethanol extract of Hedyotis corymbosa (EEHC) whole plant. Materials and methods The antinociceptive activity of EEHC was evaluated in mice using both chemical- and heat-induced pain models such as acetic acid-induced writhing, hot plate, tail immersion, formalin, and glutamate tests at 50, 100, and 200 mg/kg doses. In order to verify the possible involvement of opioid receptors in the central antinociceptive effect of EEHC, the effects found in hot plate and tail immersion tests were antagonized with naloxone. Results EEHC produced a dose-dependent antinociceptive effect against the chemical- and heat-induced pain in mice, significantly at 100 and 200 mg/kg doses. These findings suggest that the action of EEHC involves both peripheral and central antinociceptive mechanisms. The antinociceptive activity of EEHC was significantly attenuated by pretreatment with naloxone, indicating the influence of opioid receptors on the exertion of EEHC action centrally. Conclusions This study reports the antinociceptive activity of Hedyotis corymbosa and possible underlying mechanism(s) that supports the traditional use of this plant in the treatment of different painful conditions. [ABSTRACT FROM AUTHOR]

Microstructural evolution in single crystal Ni-based superalloys is investigated by the phase field simulation. During creep of the alloys, the morphology of the γ ′ phase changes from the cuboidal shape to the rafted one and the rafted structure is collapsed in the later stage of creep. It is understood that rafting is caused by the strain energy resulting from γ / γ ′ coherent interface. In this study, we focused on the decrease of interfacial coherency in creep condition and investigated the dependence of morphological evolution on it. Creep strain, misfit strain and gradient energy coefficient are changed with time in a two dimensional (2D) phase field simulation to express the γ / γ ′ interfacial transition from coherent to semi-coherent in creep condition. The semi-coherent interface model recreates the two types of microstructural evolution of the rafted structure to collapse observed in CMSX-4 and NKH71 superalloys. Furthermore, creep strain rate, instantaneous strain and time of starting the interfacial transition from coherent state to semi-coherent state decide substantially the morphology in the later stage of creep. These morphological evolutions can be explained by the relationship between the amount of creep strain and degree of coherency. [ABSTRACT FROM AUTHOR]

In a world with rapidly growing levels of automation, robotics is playing an increasingly significant role in every aspect of human endeavour. In particular, many types of mobile robots are increasingly being utilised in places and for tasks that are difficult and dangerous for humans. Although the vision of fully autonomous mobile robotic platforms that can perform complex tasks without direct guidance from a human operator is compelling, the reality is that the current state of robotics technology is still a long way from being able to achieve this capability outside of very narrowly constrained contexts. Technology advancement for improved mobile robotic teleoperation and remote control is vital to enable robotic vehicles to operate with increasing autonomy levels while allowing for effective remote operation when task complexity is too great for the autonomous systems. Being motivated to bridge this gap, we present a review of existing teleoperation methods and enhancement techniques for control of mobile robots. After defining teleoperation, we provide a detailed review that analyses, categorises, and summarises existing mobile robot teleoperation methods. Next, we highlight existing enhancement techniques that have been applied to these teleoperation methods, along with their relative advantages and disadvantages. Finally, several promising future research directions are identified. The paper concludes with a discussion of research challenges and future research possibilities. [ABSTRACT FROM AUTHOR]