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[Display omitted] • ASPN is the top differentially expressed gene in ischemic cardiomyopathy. • Aspn expression is induced in response to cardiac pressure overload or ischemia-reperfusion. • Genetic deletion of ASPN led to enhanced fibrosis and decreased cardiac function in mice after pressure overload or ischemia-reperfusion. • ASPN regulates mitochondrial bioenergetics and protects cardiomyocytes from hypoxia-reoxygenation mediated cell death. • ASPN-derived peptide prevented pressure-overload induced fibrosis and preserved heart function. • The peptide also reduced infarct size after Ischemia-reperfusion injury in mice. Heart failure is accompanied by adverse cardiac remodeling involving extracellular matrix (ECM). Cardiac ECM acts as a major reservoir for many proteins including growth factors, cytokines, collagens, and proteoglycans. Activated fibroblasts during cardiac injury can alter the composition and activity of these ECM proteins. Through unbiased analysis of a microarray dataset of human heart tissue comparing normal hearts (n = 135) to hearts with ischemic cardiomyopathy (n = 94), we identified Asporin (ASPN) as the top differentially regulated gene (DEG) in ischemic cardiomyopathy; its gene-ontology terms relate closely to fibrosis and cell death. ASPN is a Class I small leucine repeat protein member implicated in cancer, osteoarthritis, and periodontal ligament mineralization. However, its role in cardiac remodeling is still unknown. Here, we initially confirmed our big dataset analysis through cells, mice, and clinical atrial biopsy samples to demonstrate increased Aspn expression after pressure overload or cardiac ischemia/reperfusion injury. We tested the hypothesis that Aspn, being a TGFβ1 inhibitor, can attenuate fibrosis in mouse models of cardiac injury. We found that Aspn is released by cardiac fibroblasts and attenuates TGFβ signaling. Moreover, Aspn−/− mice displayed increased fibrosis and decreased cardiac function after pressure overload by transverse aortic constriction (TAC) in mice. In addition, Aspn protected cardiomyocytes from hypoxia/reoxygenation-induced cell death and regulated mitochondrial bioenergetics in cardiomyocytes. Increased infarct size after ischemia/reperfusion injury in Aspn −/− mice confirmed Aspn's contribution to cardiomyocyte viability. Echocardiography revealed greater reduction in left ventricular systolic function post-I/R in the Aspn −/− animals compared to wild type. Furthermore, we developed an ASPN-mimic peptide using molecular modeling and docking which when administered to mice prevented TAC-induced fibrosis and preserved heart function. The peptide also reduced infarct size after I/R in mice, demonstrating the translational potential of ASPN-based therapy. Thus, we establish the role of ASPN as a critical ECM molecule that regulates cardiac remodeling to preserve heart function. [ABSTRACT FROM AUTHOR]

Adapted to effectively capture oxygen from inhaled air and deliver it to all other parts of the body, the lungs constitute the organ with the largest surface area. This makes the lungs more susceptible to airborne pathogens and pollutants that mediate pathologies through generation of reactive oxygen species (ROS). One pathological consequence of excessive levels of ROS production is pulmonary diseases that account for a large number of mortality and morbidity in the world. Of the various mechanisms involved in pulmonary disease pathogenesis, mitochondrial dysfunction takes prominent importance. Herein, we briefly describe the significance of oxidative stress caused by ROS in pulmonary diseases and some possible therapeutic strategies. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract The objective of the present study is to improve iron bioavailability using high-density gastroretentive pellets of zero valent iron nanoparticles (ZVINPs). ZVINPs were prepared by the chemical reduction method and were characterized for surface morphology, surface charge, and thermal properties. High-density gastroretentive pellets of iron nanoparticles were prepared using spheronization technique. Pellets were characterized for its micromeritic properties, in vitro drug release, and ex vivo permeability. The pharmacokinetic parameters, organ distribution, and toxicity of the optimized pellets were investigated in Wistar rats. In vivo results revealed more than 2-fold increases in oral bioavailability of iron by pellets compared to plane ferrous sulfate. Toxicological studies of the carriers indicated no evidence of liver damage in acute treatment; however, few complications were observed in chronic treatment groups. These results indicated that ZVINPs pellets successfully improve the oral iron bioavailability but need to obtain more information on repeated dose toxicity to initiate the clinical evaluation of investigational products. [ABSTRACT FROM AUTHOR]

Abstract The effect of the distribution of aluminum layer through the thickness of fiber metal laminates (FMLs) on their projectiles impact response is studied using high speed 3D digital image correlation technique (DIC). The FMLs consisting of aluminum alloy 2024-T3 sheets of thicknesses 0.3 mm, 0.4 mm, and 0.6 mm and glass fiber reinforced epoxy layers (two layers with each of 0° and 90°) were prepared by the hand layup process followed by vacuum bagging. The metallic layers are placed at different locations through the thickness of four different layups while keeping the total metal layer thickness constant. The hemispherical and conical nose projectiles of the same mass are impacted normal to the FMLs plate using nitrogen gas gun. The performance of the FMLs is evaluated using different parameters such as the deformation history, residual deformation and also the surface and internal damages. FML 4/3–0.3 in which the two adjacent composite layers with different fiber orientations separating by an aluminum layer exhibited the highest deformation with hemispherical projectile impact for the same impact energy level. The deformation was found to be lower and nearly same for the other three FMLs. This observation is also noticed in the case of drop weight impact (low velocity impact). The FML 2/1–0.6 in which the composite layers were stacked together exhibited a comparatively higher lateral spread of delamination and interlayer opening with hemispherical projectile impact when compared to FML 4/3–0.3, indicating that the lateral spread of damage within the FML can be decreased by distributing the aluminum layers in the FML. This is also observed in the case of drop weight impact. Highlights • The projectiles impact response of aluminum based fiber metal laminates (FMLs) has been investigated using high speed 3D digital image correlation technique. • Internal damages are identified by slicing the specimen. • Effect of meal layer distribution through the thickness of FMLs on the projectiles impact response of FMLs is brought out. • Damage pattern is affected by distributing the aluminum layers through the thickness with more extent of damage exhibited by projectiles impact. • Hemispherical projectile impact imparts more collateral damage to that of conical projectile. [ABSTRACT FROM AUTHOR]

This study focuses on the effect of metal layer distribution in glass fibre reinforced aluminium laminates (GLARE) subjected to low velocity impact. Four GLARE variants specimens were considered in which the metal layers of different thicknesses were placed at various positions in the layup while keeping the same total metal layer thickness. Experiments and Finite element (FE) analysis were performed to understand the behaviour of the GLARE specimens. A user written material subroutine VUMAT which incorporates Hashin failure criteria along with Puck's action plane concept were used to predict the response of the composite layers. The damage was evolved for each failure mode using the exponential damage evolution law. Interface delamination between the layers was initiated by cohesive surface behaviour which includes the friction effect between the plies. It was found that placement of thinner metal layer on top of the laminate and its distribution inside the layup lowers the impact resistance of GLARE. Moreover, the patterns of delamination are also affected by the placement of metal layer within the laminates. It was further shown that the propagation direction of delamination is governed by the fibre direction of lower ply of the interface. [ABSTRACT FROM AUTHOR]

The effect of distribution of aluminum layer through the thickness of fiber metal laminates (FMLs) on their low velocity impact response was studied. The FMLs were prepared using aluminum 2024-T3 layers (0.3, 0.4, 0.6 mm thickness) and glass fiber reinforced epoxy (two layers of 0° and 90° each) through hand layup followed by vacuum bagging. The four different layups considered had metallic layers placed at different locations through the thickness while maintaining the total metal layer thickness constant. The FMLs were subjected to low-velocity impact using a drop weight testing machine. The performance of FMLs was evaluated using different parameters such as maximum force, energy absorbed, damage degree, dent depth and maximum deflection. Among the four FMLs, it was observed that the FML 2/1–0.6 in which the composite layers were stacked together had lower levels of cracking and deformation and recorded the highest force for the same impact energy level, whereas the FML 4/3–0.3 in which two adjacent composite layers having different fiber orientations were separated by metallic layer recorded the lowest force and maximum cracking and deformation. The lateral spread of delamination and interlayer opening was comparatively greater for 2/1–0.6 when compared to 4/3–0.3, indicating that distributing the aluminum layers in the FML can decrease the lateral spread of damage within the FML. [ABSTRACT FROM AUTHOR]

Fiber metal laminates (FMLs) consist of layers of thin metallic sheets and fiber reinforced composite layers bonded together. In the present study, the tensile response of FMLs consisting of aluminum 2024-T3 (Al) sheets of thicknesses 0.2, 0.4, and 0.6 mm and uni-directional glass-fiber reinforced composite layers are investigated. FMLs having three different stacking sequences, all having the same total metal layer thickness were prepared using the hand layup process. The results of the tensile tests indicated that the layup sequence did not have any influence on the initial modulus of the FMLs. However, the ultimate strength and the post ultimate strength behavior of the FMLs are significantly affected by the layup sequence. In order to gain more insight into the sequence of damage evolution, a detailed finite element analysis (FEA) of the tests was also carried using the commercial software ABAQUS. The Hashin failure criterion was used to model failure of composite layers and cohesive surface interaction was used to capture inter-layer delamination. [ABSTRACT FROM AUTHOR]

Low velocity experimental and numerical study have been performed on four layer [0°/90°] s and [90°/ − 45°/+ 45°/0°] s composite laminates at three different energy levels to observe the damage mechanism and delamination pattern. Experiments were performed using a drop weight testing machine as specied in ASTM D5628 FA while numerical analysis was executed using Abaqus Explicit. Hashin failure criteria is used to capture the intra-layer damage modes while surface based cohesive behaviour with quadratic stress failure criteria was used to predict delamination. It was observed from the results that matrix cracking occurred first followed by the delamination. The tensile fiber failure mode triggered at the peak force after which the damage energy stabilises to a particular value. For [0/90] s laminate, larger peanut shaped delamination profile is noticed on the third interface from the impact face along the 0°fiber direction. However, [90/ 45/+ 45/0] sequence profile was oriented along -45°laminate in the second interface from the impact face. The size of profile increases from impact side interface to non-impact side interface due to the increasing flexural stresses. The area of the profile tends to increase with increasing energy and this increase is dominated by the length rather than width. Results of numerical simulations were found to be in good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

The study of different porous and granular materials like polyurethane foams, aluminium foams, aqueous foam, sand, saw dust etc. for shock mitigation have been reported in literature using shock tubes. But the shape of explosively generated blast wave is different from the shock wave generated using shock tubes. The present paper deals with the study of generation of blast waves in laboratory using a blast wave generator. The blast wave generator is a shock tube with high pressure (Driver) and lower pressure (Driven) sections separated by a solid metal diaphragm. In this, the blast wave profile is produced within the tube by adjusting the driver section length. Then modification of blast wave pressure through open cell rubber foam is studied by varying the thickness of foam sample. The results show that the presence of the foam initially amplifies the end plate pressure as reported in the literature. But with increase in the foam thickness the end plate pressure starts decreasing and finally mitigation is observed for foam thickness more than the critical thickness. [ABSTRACT FROM AUTHOR]

The low-velocity impact behaviour and energy absorption mechanisms of fibre​ metal laminates (FMLs) at different impact energy levels before the first composite failure are derived analytically using a mass–spring arrangement. Four FML layups comprise glass fibre/epoxy layers and titanium alloy Ti-6Al-4V sheets, unveiling the same total metal layer thickness. The impactor mass consequence is also predicted. The results specify that the deformation energy of FML constituents accounts primarily for the FMLs overall energy absorption, 86%–93%, and 87%–93%, with both membrane and bending strain energy, and membrane strain energy only, separately. Here, a higher percentage of energy is absorbed by FML 4/3–0.3, followed by FMLs 3/2–0.3(O), 3/2–0.4, and 2/1–0.6. FMLs are 16 % more impact resistant than equivalent monolithic titanium. Also, the predicted force history of FMLs is in good comparison with experiments at 30 J, with membrane energy only correlating well than with both membrane and bending energy. The estimated maximum force, entire energy absorption of FMLs is realistic with experiments at 30 J, 45 J, and 60 J. The predicted response of aluminium-based FMLs also matches well with experiments at various energy, preserving the presented model strength. Further, the behaviour of FMLs is to be comparable under low- and high-mass impactors. However, FMLs maximum force and energy absorption seem to be correspondingly lower and higher under a high-mass impactor. Higher impact resistance seems to be displayed by titanium- to aluminium-based FMLs. Also, the above FMLs appear to display higher total energy absorption under low- to high-velocity impact. • The low-velocity impact behaviour of titanium-based FMLs before the first composite failure is analytically predicted. • The deformation energy of FML constituents contributes primarily to the FMLs overall energy absorption, 86%-93%, at 30 J. • The energy partition of FMLs is affected by dispersing titanium layers. • The predicted response of titanium- and aluminium-based FMLs matches well with experiments at different energy. • Higher impact resistance is shown by titanium- to aluminium-based FMLs. • The higher energy absorption of FMLs appears under high-mass impactor and low-velocity impact. [ABSTRACT FROM AUTHOR]

ZnO nanostructures with various aspect ratios have been synthesized for H 2 gas detection applications. The thermal-decomposition method was employed at different annealing temperatures (350, 450, and 550 °C) and its impact on various shapes/sizes of ZnO nanostructures is demonstrated. Thermal decomposition performed at 350 °C exhibited a maximum (∼6.25) aspect ratio among them. Its capability of H 2 sensing was also observed to be maximum by realizing ∼483% of sensor response at 180 °C under H 2 gas concentration of 80 ppm. The sensor response is ∼3 times (∼177%) and ∼9 times (∼53%) higher at ZnO nanostructure synthesized at 350 °C than at 450 °C, and 550 °C, respectively. The higher sensor response has been attributed to the increased availability of active surface area for adsorption/desorption of gas molecules. ZnO@350 nanostructure showed significantly higher selectivity towards H 2 gas than other target chemical inputs. We have also studied H 2 -induced metallization on the surface of ZnO nanostructures which plays an important role for improving the selectivity and sensor response. This study provides insight into the role of aspect-ratio-controlled shape/sized ZnO in improving H 2 gas sensing. [Display omitted] • Aspect-ratio-controlled ZnO nanostructures for H 2 gas sensing was examined. • The maximum sensor response (∼483%) for ∼6.25 aspect ratio ZnO was observed. • ZnO-nanorods pose higher active surface area than NPs that reduced operating temperature. • The sensor response is ∼3 times and ∼9 times higher at 350 °C than at 450 °C, and 550 °C. • H 2 -induced metallization on ZnO surface significantly improved the sensor selectivity. [ABSTRACT FROM AUTHOR]

• Part I explores the projectile impact response and damage of titanium-based fiber metal laminates (FMLs) using air gun set up. • The damage pattern, energy absorption, and opening of delamination between different layers are affected by distributing titanium layers through the thickness. • The ballistic resistance of FMLs is found to be independent of the dispersion of metallic layers within FMLs. • The lateral delamination spread, interlayer opening, and global bending deformation of titanium-based FMLs seem lower than aluminium-based FMLs. This two-part article examines the distribution of metallic layers through the thickness of fiber metal laminates (FMLs) on their response and damage when subjected to high-velocity projectile impact. Glass fiber/epoxy and Ti-6Al-4V titanium alloy sheets are used to obtain four different layups of FMLs fabricating by the hand layup process and exhibiting the same thickness of the total metal layer. Part I deals with experimental investigations of fully clamped square FMLs normally impacting at the center by hemispherical steel projectile using compressed air gun set up. Different parameters are considered to evaluate the FMLs' performance, which includes damage degree, first cracking energy, crack length, deformation profile, and damage developed on the surface and inside the laminate. The results indicate that the highest permanent deformation and cracking are exhibited by FML 4/3-0.3, exhibiting separation of composite layers with different orientations by the metallic layer. The other FMLs exhibit lower and approximately similar permanent deformations. However, lower cracking and a relatively higher lateral delamination spread and opening of the interlayer are exhibited by FML 2/1-0.6 in which composite layers are arranged together than FML 4/3-0.3, signifying that the damage spreading laterally can be reduced by dispensing titanium layers. The ballistic resistance is found to be similar for FMLs. The levels of permanent deformation, cracking, and delamination with their opening and spreading are lesser for titanium-based FMLs than aluminium-based FMLs. The ballistic response of FMLs will be evaluated using analytical modeling in an accompanying study (Part II). [ABSTRACT FROM AUTHOR]

• Part II deals with the dynamic response of titanium-based FMLs undergoing ballistic impact using analytical modeling. • The leading part of the total energy absorption of FMLs is by bending and membrane energy absorption associated with the deformation of FML constituents (68 % - 72 %). • Varying placements of the titanium layers affect the partition of the energy absorption of FMLs. • The predicted ballistic resistance parameters of FMLs are found to be in good agreement with experiments. This two-part article scrutinizes the influence of metal layer distribution through the thickness of titanium-based fiber metal laminates (FMLs) on their high-velocity projectile impact response and damage. The four different layups of FMLs consist of layers of glass fiber/epoxy and Ti-6Al-4V titanium alloy sheets, exhibiting the thickness of the total metal layer the same. Part I presents the experimental investigations of fully clamped FMLs demonstrating performance parameters, damage mechanisms, and ballistic resistance. Part II concerns the ballistic impact behavior of FMLs using analytical modeling, which is based on test results obtained in an accompanying study. An equivalent mass-spring system is used to obtain the transient deformation, ballistic limit, and absorbed energy of the laminate by various mechanisms. Good agreement is obtained between experimental and analytical ballistic limit velocity. The foremost part of the total energy absorption is by bending and membrane energy absorption (68 % - 72 %), with FML 4/3-0.3 absorbing a higher percentage of aforementioned energies followed by that of both FMLs 3/2 and FML 2/1-0.6. The predicted total energy absorption by several damage mechanisms of FMLs at the ballistic limit displays a reasonable matching with experiments. [ABSTRACT FROM AUTHOR]

Layers of thin metallic sheets and fiber-reinforced composite layers bonded together is known as fiber metal laminates (FMLs). In the current study, titanium Ti–6Al–4V sheets are used with thicknesses 0.2 mm, 0.4 mm and, 0.6 mm along with layers of unidirectional glass-fiber reinforced composite to produce FMLs and the tensile response of these laminates are examined. Four different stacking sequences of FMLs have been considered exhibiting the same thickness for the total metal layer and the hand layup process is used to prepare these laminates. An orthotropic plasticity theory of macro mechanical type and classical laminated plate theory are considered to model the elastic-plastic type of behavior of titanium-based FMLs. A plastic potential function based on three parameters is used to the model the orthotropic plasticity. Behavior with linearly elastic and orthotropic elastic-plastic types is assumed for the layers of glass composite and titanium, respectively in the laminated plate theory. The results show that the initial modulus of FMLs has not been influenced by the sequence of the layup, while this sequence of layup does considerably affect the response of FMLs following ultimate strength. The properties of FMLs such as failure strain and toughness which are important parameters from a design point of view of FMLs can be altered to absorb energy at dissimilar rates, i.e., by insulating the composite layers from each other by metallic layers in case of FMLs 3/2–0.4, 4/3–0.2(O) and 4/3–0.4(O). The model with orthotropic plasticity is found to be precise up to the total strain level of 2.1%, i.e., close to the failure of composite layers within FMLs, when compared with results measured from experiments. The behavior with stress-strain predicted by laminated plate theory also finds realistic up to the total strain of 2.1% to describe the corresponding behavior obtained from experiments. • The quasi-static tensile behavior of titanium-based fiber metal laminates (FMLs) has been investigated. • The real-time damage evolution within the edges of FMLs is monitored using a pair of mirrors. • The consequence of the dispersion of the metallic layer has been recognized on the response of FMLs. • The prevention of crossing of damage from one to adjacent composite layer results in more progressive failure of FMLs. • The response of FMLs predicted by classical laminated plate theory is found to be in good agreement with experiments. [ABSTRACT FROM AUTHOR]

In this study, tensile behavior of Glass Fiber Reinforced Polymer (GFRP) sandwiched with different thickness aluminium alloy layers were investigated at strain rates of the order 400–480 /s. The loading was induced through Spilt Hopkinson Tensile Bar (SHTB) setup and specimen size and shape were determined through Finite Element (FE) analysis by ensuring all damage modes should evolve inside the gauge region of the specimen. Three GLAss fiber REinforced (GLARE) aluminium laminates with top/bottom metal layers apart from the inside layer(s) were investigated. The idea is to observe the dynamic response of these laminates when they are sandwiched with no metal layer, one metal layer and two metal layers inside their lay-up configuration. They were named as 2/1–0.6, 3/2–0.4 and 4/3–0.2(O) laminates respectively. The FE analysis is used to observe the damages occurred within these laminates which are later compared with the experimental results. However, FE analysis results were able to investigate in-depth damage and failure occurring in these laminates unlike in experiments. Johnson-Cook (J-C) damage model was used as a material model for metal layer modeling while for GFRP a strain rate dependent 3D Hashin damage user-defined model is incorporated via VUMAT to observe the failure occur in these laminates. The interface delamination between the laminas were invoked through cohesive surface methodology. The GLARE laminates with metal layer(s) inside the configuration i.e. 3/2–0.4 and 4/3–0.2(O) laminates, was found to have comparable strength with GLARE having no metal layer inside the layup i.e. 2/1–0.6 laminate. From FE analysis it was noticed that the initiation of delamination due to the formation of matrix cracks in quasi-static loading was delayed in high strain rate loading as the strength in the matrix failure mode was higher due to rate sensitivity. However, the sequence of failure events occurring in these laminates like metal yielding, matrix failure, fiber failure accompanied with delamination remains same as in quasi-static loading. • GLARE laminates were investigated at high strain rate tensile loading and sequence of failure events were analyses through FEM. • The modeling of the split Hopkinson bar is described with important tips to the reader for its designing. • Allows the reader to ascertain and design their laminates accordingly before applying them to dynamic loading scenario. • FMLs were found to be having the same strength in dynamic loading conditions irrespective of the dispersion of metal layers in their configuration. [ABSTRACT FROM AUTHOR]

The increasing dependence on the communication network in monitoring, operating, and controlling power systems increases the threat of cyber-attacks. Cyber attacks could harm the power system's functioning and cause substantial economic losses. Malicious injection of compromised synchrophasor measurements is capable of hampering adequate control actions and jeopardizing the security and reliability of the power system. To tackle this issue, an adequate method for detecting cyber intrusion in the communication network should be developed for the secure operation of the cyber–physical power system. Blockchain has evolved as a proven technology that holds the potential for enhancing grid security. In this paper, we investigate the application of blockchain for enhancing grid security and propose a random sequence-based symmetric encryption algorithm that uses a blockchain-based secure platform for sharing the decryption keys. The presence of cyber-attack has been identified using a weighted least square-based state estimator. We have further developed a cyber-attack simulator application that could emulate the behavior of a false data injector and proposed the attack detection mechanism. The developed technology has been tested on IEEE 14 bus test systems. • Cyber-physical power system framework using RTDS, MATLAB, and Raspberry Pi. • Coordinated and uncoordinated cyber intrusion and detection in power systems. • Blockchain-based cyber security enhancement of Power Systems. • A cyber attack simulator application has been developed using MATLAB. [ABSTRACT FROM AUTHOR]

Highlights • The wire rope failed in fatigue mode with typical square breaks with no lubrication. • Bending fatigue life calculated and it was 6 months in ideal condition. • The schedule of changing of wire rope was modified and NDT checking was recommended. Abstract A 6 × 36 construction wire rope conforming to IS 7904: 1995-X grade of high carbon steel failed after nine months of service. Visual observation revealed broken strands with dry damaged core and inter-strand nicking along its length. The dry core indicated insufficient lubrication. The fractured end of wire rope exhibited crown/chisel shaped marks and fractography using SEM showed striations confirming initiation by fatigue. The appropriate bending fatigue upon consideration of factor of safety, sheave diameter, rope diameter, co-efficient of sheave shape, working load and metallic area was estimated to be six months. Microstructural examination exhibited drawn pearlite in the matrix. Improper lubrication led to fretting wear between the internal wires resulting in failure of individual strands while rest of them were unable to carry the tensile load in service. Additionally, bending fatigue was predominant when it passed through the sheave during which inter-strand nicking occurred. Changing of the schedule of the wire rope from 9 to 6 months was recommended. Proper inspection by NDT and application of heat resistant lubricant like super micronized solid lubricant -molybdenum should be implemented to avoid such failures in future. [ABSTRACT FROM AUTHOR]

A novel time–current-rate-based inverse characteristic curve for relays in a DC microgrid is proposed in this paper. Line current rise rate is used as actuating quantity, ensuring quick line fault clearing (relay operating time is in order of a few μ s). The advantage of using line current rise rate as actuating quantity is that for a line short-circuit fault, it does not vary significantly for grid-connected and islanded modes of operation and varying network topologies of DC microgrid. Consequently, using the proposed characteristic, a single set of optimal relay settings is obtained using an optimization solver in MATLAB. The obtained settings ensure reliable and selective coordination between primary and backup relays for various pole-to-ground and pole-to-pole line faults under different operating conditions with multiple sources in two different 4-bus 400V low voltage DC microgrids. The maximum relay operating time for a high resistance fault with the proposed curve is 394. 9 μ s for the first considered low voltage DC microgrid. Simulations in the Real Time Digital Simulator and comparisons with previous schemes (one comparison on the second considered DC microgrid), conventional standard inverse, and extremely inverse curves for DC microgrid protection indicate the effectiveness of the proposed scheme. • A time–current-rate-based inverse relay operating curve in DC microgrid is proposed. • Relay operating time is in order of few microseconds for proposed work. • Optimal settings ensure selective coordination among primary and backup relays. • One optimal relay setting is robust to system operating modes and reconfiguration. [ABSTRACT FROM AUTHOR]

Demand response is becoming increasingly important due to the high penetration of intermittent and variable renewable energy and electric vehicles in power systems. Real-time Incentive-Based Demand Response (IBDR) is helpful for power balancing in normal and emergency scenarios. The paper focuses on making an efficient IBDR scheme and increasing the participation of residential customers. A feature in the Home Energy Management System (HEMS) that provides the quantity of flexible load demand available with the residential customers for real-time IBDR in a decentralized scheme is explored. This paper analyzes the scheduling of flexible residential appliances in a dispersed manner over time by HEMS to increase the participation of residential customers in real-time IBDR. The error accumulation in the IBDR in a decentralized scheme due to the discrete character of residential appliances is examined and addressed. A financial ratio is proposed to give a fair opportunity to all the participants in IBDR when the cumulative flexible load demand available with the participants is greater than the required quantity of demand response. This paper provides algorithms that improve demand response systems by increasing the flexibility available to participants, reducing the error accumulation in IBDR, and ensuring the fairness of the IBDR opportunity to participants. The simulation analysis is done with 400 residential customers with a different number of flexible appliances and different energy requirements. The paper highlights the potential benefits of using a decentralized scheme to enable real-time IBDR in power systems. • Real-time Incentive-Based Demand Response (IBDR) is beneficial for balancing power. • The dispersed scheduling increases consumer participation in real-time IBDR. • The error in the IBDR due to the discrete nature of residential appliances is solved. • A financial ratio is proposed to provide equal opportunities for all IBDR participants. [ABSTRACT FROM AUTHOR]