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Growing concerns about seismic events enforced structural engineers and architects to embrace the hazardous effect of ground motion in design. To address this, researchers have developed various base isolation (BI) techniques. This study comprehensively reviews BI system types, techniques, and implementation. Exploring the dynamic response of three-dimensional BI devices and the mutual effects of isolation devices and soil-structure interaction during strong ground motion, the paper covers topics such as seismic isolation of nuclear power plants, cost analysis, and various optimization techniques. Furthermore, the paper investigates the behavior of isolation devices in beyond-design events, including blast and aircraft impact loading. In general, the seismic isolation and control device response is demonstrated through shaking table tests and computational analysis. The study sheds light on the functions of seismic isolation system by comparing them with fixed base structures. Additionally, the paper presents codal recommendations, recent advancements, and current practices, aligning them with historical developments and past reviews of different BI techniques, along with their advantages and disadvantages. In conclusion, the closing remarks emphasize the future research prospects in this field. [ABSTRACT FROM AUTHOR]

This paper analyses the performance of multilevel half-bridge bidirectional DC–DC converter (MHBDC) under wide change in voltage transformation ratio. The advantage of MHBDC topology over conventional isolated bi-directional dc–dc converter (CIBDC) includes reduced voltage stress across the semiconductor switches and the transformer windings, which is suitable for high voltage applications in DC microgrids. Microgrids is inclined to voltage variations at both input and output side, which direct towards increased current stress in MHBDC. The rise in current stress can be minimized by employing various phase shift modulation techniques. The paper presents steady state time domain analysis of MHBDC under conventional phase shift modulation (CPSM), extended phase shift modulation (EPSM) and dual phase shift modulation (DPSM). A computational procedure is developed and demonstrated to obtain the phase shift angles at minimum value of current stress and varying voltage transformation ratio in the converter. Current stress analysis, soft switching region of operation and reverse power flow analysis in MHBDC are examined under different modulation schemes. A 1.5 kW hardware prototype of MHBDC is built, evaluated and presented the results. Power loss analysis and efficiency plots for the converter is determined and quantitatively evaluated with different modulation techniques considering high, medium and low power ranges. [ABSTRACT FROM AUTHOR]

This paper attempts to provide a clear explanation of how the concept of double frequency complex plane is applied to the calculation of complex electrical power. This is a step to remove the confusion associated with the calculation of complex electrical power that has persisted in the scientific community to this day. It starts with a discussion on the conventional method of calculation of complex power and its relation with the Steinmetz’s original method of power calculation in steady state AC circuit. An excerpt from the writing of Steinmetz is then included in which he enumerated mathematical equations that were used to make adjustments while calculating two times the supply frequency complex electrical power from the supply frequency complex voltage and current. Since the equations appear to contradict the laws of conventional complex algebra, considerable confusion arose soon after the Steinmetz’s publication. This confusion persists even today. Usual text books do not touch upon this issue and merely describe the mathematical equation required for calculation of complex power. This paper tries to provide a justification behind the adjustment equations involving double frequency complex plane used for complex power calculation through a simple R-L circuit and provide analytical explanation of the equations enumerated by Steinmetz. [ABSTRACT FROM AUTHOR]

The space debris in Earth's orbit has increased drastically due to the failure of spacecraft, rocket bodies, and mission-related objects. These objects in orbit increase the space waste and challenge other flying objects such as spacecraft. A hypervelocity impact of space debris on spacecraft structures can have a range of effects (mechanical damage and functional failure), raising significant concerns about spacecraft safety. This paper reviews the different studies on the performance and development of the Whipple shield against the hypervelocity impact of space debris. The study focuses on the impact mechanism, dynamic Fragmentation of materials, strength models, Equation of state, characteristics, and model of the debris cloud. The strength models (Steinberg–Guinan and Johnson–Cook) and Mie–Gruneisen equation of state, primarily used for hypervelocity impact applications, are thoroughly covered in this study. The study also reported the various experimental and numerical techniques for high and hypervelocity impact. The study concluded that mesh-based, mesh-free, and hybrid finite element methods are reliable for analyzing Whipple shield targets to resist hypervelocity impact. The study also observed that the two-stage light gas gun technique investigates most experimental analyses of hypervelocity impact on the Whipple shield. Alongside reviewing the abovementioned aspects, this paper also underlines the future scope of study in this paradigm. The authors strongly believe that this study provides more insights into the fundamentals and perceptions of the Whipple shield to protect the spacecraft against the hypervelocity impact of space debris. [ABSTRACT FROM AUTHOR]

Sparse code multiple access (SCMA) is a novel code domain non-orthogonal multiple access scheme that enables the overloading of the fifth generation multi-user system. SCMA accommodates massive user connectivity, higher spectrum efficiency, low latency, flexible service multiplexing, etc. Integrating SCMA with cognitive features empowers the exploration of more frequencies under the spectrum scarcity issues. This paper proposes spectrum sensing with SCMA technology with an maximum passing algorithm (MPA) detector for multi-user detection at the receiver side. A novel double threshold based log-likelihood ratio MPA detector has been used for spectrum sensing in cooperative cognitive radio networks for Rayleigh fading, Rician fading and generalized Nakagami fading channel. The analytical detection performance versus signal to noise ratio (SNR) curve has been compared with the simulation results for the corresponding fading channels. The simulation results verify the SCMA-based system model performance in terms of detection probability well matched with analytical results. The paper also includes the comparative study of detection probability vs SNR under Rayleigh, Rician and Nakagami fading channel. [ABSTRACT FROM AUTHOR]

This paper presents a wind tunnel investigation of flow over symmetrical sinusoidal two-dimensional hills. A total of three hill models are tested which extend fully across the width of the wind tunnel in the direction perpendicular to the wind flow. The three hills have slopes equal to 15° (S1 hill), 30° (S2 hill), and 45° (S3 hill). Two independent studies are carried out: Wind flow characteristics study and Force measurement study. Wind flow characteristics study is carried out on the three hills and the results measured include mean wind velocity and turbulence intensity profiles. It is followed by a force measurement study carried out on a rectangular plan rigid building model which is placed near and on top of all the three hills at a total of 17 locations for each hill. Results measured include along-wind base shear forces and base moments. It is observed that the steeper hills (S2 and S3) have regions of high turbulence intensities extending beyond the crest region to a distance of 4H and 6H (where H is the hill height) respectively. The maximum average amplification factor for all the three hills is observed at the crest. The maximum along-wind base shear force for the building is reported to be highest for the shallowest hill (S1 hill) just upstream of the crest. Increased along-wind base moment for the building up to a factor of 5.5 is observed at the crest for S1 hill. This paper is expected to be of great help to structural engineers designing buildings in hilly terrains. [ABSTRACT FROM AUTHOR]

Structural walls are subjected to axial load with bi-axial bending. Despite this, structural walls are designed considering the demand along the strong axis. However, to minimize damage to structural wall it is necessary to design structural walls considering P–Mx–My interaction. Currently, IS 456:2000 recommends design P–Mx–My interaction for columns using a non-dimensional parameter ( α n ). In theory, the recommended α n are meant for symmetric column sections with uniform distribution of longitudinal reinforcement. Consequently, it is necessary to verify the applicability of the design P–Mx–My interaction equation for structural walls. Furthermore, the α n values recommended in the design code are shown to underestimate the flexural capacity of columns, particularly at lower axial load ratios (i.e., Pu/Puz; where Pu is the axial load demand and Puz is the maximum compressive load capacity of the column). To address these issues, the paper recommends design α n values for rectangular RC structural walls. Additionally, the paper presents simplified design equations to develop bi-axial interaction for structural walls. The simplified equations present in this paper are developed using regression analyses of rectangular structural walls with: (a) aspect ratios ranging between 4 and 25, (b) longitudinal reinforcement ratios from 0.5% to 1.5%, (c) reinforcement grades of 415 and 500 MPa, and (d) grade of concrete between M20 and M55. The proposed bi-axial interaction for structural walls will help designers to assess the adequacy of wall with relative ease. [ABSTRACT FROM AUTHOR]

The smart city projects have been criticized for their technocratic approach, often seen as prioritizing technology over other essential aspects of society. The digital solutions developed by technology firms fail to address the needs of deprived and vulnerable communities in society because the dominating sociotechnical imaginary that emerges from outsourced solutions ends up ignoring localized ones. Using a preference-based model to address the crucial problem of choosing the right technology for waste treatment, the paper highlights the importance of taking into account a variety of imaginaries and urban futures when choosing a waste disposal method for urban local bodies. In order to reduce uncertainty in the choice of waste disposal methods in Indian cities, the paper suggests a method based on grey theory which is modified for preference-based analysis. This approach lessens the requirement for cost and benefit attributes by incorporating the significance of design criteria in decision-making. The approach is contrasted with earlier approaches and demonstrated with a waste disposal issue in Indore, India. For socio-technical transformations in cities to be successful, the study highlights the significance of localized solutions and diverse imaginaries. The approach that involves choosing and allocating weights to criteria is strongly supported by the quantitative methodology, which involves interviews with officials, NGOs, experts, citizens, and traders. [ABSTRACT FROM AUTHOR]

In this paper, the characteristics of flow-induced noise in ethylene cracking furnace tubes were analyzed, under both pre- and post-coking conditions, using the Large-Eddy Simulation (LES) and generalized Lighthill's acoustic analogy model. The results revealed that the flow-induced noise was broadband noise, with rapid attenuation occurring in the frequency range of 100–7800 Hz, and the primary energy concentrated between 25 and 500 Hz, in comparison to normal conditions. Acoustic sources coincide with areas of significant pulsations of static pressure and flow velocity, particularly above and behind the coke. Employing the Spearman correlation method for comparative analysis, it was observed that as the ratio of coke height to tube diameter (expressed as H/D) increased from 1/8 to 3/4, the proportion of static pressure pulsation decreased from 0.98 to 0.80, and the proportion of pulsating flow velocity decreased from 0.43 to 0.22. The data indicates a robust correlation between acoustic source and the static pressure pulsation. However, with the increase in coke, this correlation gradually diminishes, particularly concerning the pulsating flow velocity, where attenuation reached 48.83%. Additionally, the position and size of coke in the furnace tube can be determined using the Overall Sound Pressure Level (OASPL) curve measured in the tube. This OASPL curve exhibits distinct peaks, with corresponding OASPL values of 109 dBA, 120 dBA, 124 dBA, 131 dBA, and 149 dBA, respectively. The results presented in this paper offer essential insights for ensuring the safe operation of ethylene cracking furnace tubes. [ABSTRACT FROM AUTHOR]

As the requirement for underground space is growing mainly in metropolitan cities, building a new underground tunnel in the locality of the in-service tunnel is one of the most common situation. Building a new tunnel might induce additional strain and stress modification resulting in damage to the in-service tunnel. This paper reviews from the research works conducted by earlier investigators on the subject matter under four categories, field monitoring, scale down modelling, numerical and theoretical approach. The purpose of this paper is to review recent developments and improve understanding of this issue. The drawbacks of each category and gray areas which need further investigation are presented in this paper. This review paper could facilitate the work of practising engineers and researchers by highlighting the problem and areas where requires further research. [ABSTRACT FROM AUTHOR]

Forecasting of load is essential for operating power systems. India recently witnessed one of the worst power crisis with the highest ever power demand of 207 GW on April 29, 2022. The demand in the month of May and June 2022 was estimated to reach 215 GW. The peak demand this year 2023, according to the electricity ministry, is predicted to be around 230 GW from April to June. The inability to meet certain fundamental issues as power can take a toll on any country's economy. Proper prediction helps in proper decision making and planning. The main objective of this paper is to predict day ahead electrical load demand for Assam. Statistical and Machine Learning Algorithms has been studied. The study has been carried out using real-time data for the years 2016, 2017 and 2018. The paper presents a detailed analysis of the different hyper parameters of the deep learning models and their effect is seen on the learning efficiency. A novel stacked forecasting model is proposed using neural networks as base learners and CatBoost as the meta-learner. The performance of the proposed model has been evaluated and compared with individual models in terms of training time and accuracy using different error metrics namely MAE, MSE, RMSE, MAPE and R2 score. A comparison of the proposed prediction model with the prediction models available in literature has been presented. The conclusion states that both the statistical and machine learning algorithms used in this study act as useful tools for daily load forecasting with considerable accuracy; yet machine learning algorithm outperforms the statistical methods. The entire work has been done in Google Colaboratory using Python as the programming language. [ABSTRACT FROM AUTHOR]

The Degree of Linear Polarization (DoLP) is a key dimension of information in polarization imaging. The quality of polarization images is greatly affected by imaging equipment and environmental factors. Therefore, an enhancement method for the DoLP image is proposed in this paper. First, a super-resolution reconstruction algorithm based on the Detail Enhancement Guided Image Filter is proposed to solve the problem of mosaicization and pseudo-polarization information caused by the degradation of spatial resolution and super-resolution reconstruction of DoFP imaging. Second, for the problem of rapid degradation of polarization image quality caused by hazy environment, a DoLP enhancement algorithm based on multi-channel difference Signal-to-Noise Ratio is proposed to improve the visual effect of polarization images in different scenes with hazy environment. The method proposed in this paper implements super-resolution reconstruction, demosaicing, pseudo-polarization information removal, and adaptive enhancement of DoLP images in DoFP systems. [ABSTRACT FROM AUTHOR]

Counter circuits play a crucial role in Modified Booth Wallace (MBW) tree multiplier architectures, serving as fundamental partial product accumulation circuits. In this paper, we propose a novel architecture for a low-power 7:3 counter based on hybrid full adders (HFAs). Two new designs of HFAs are introduced to realize this counter, enabling the implementation of a 7:3 counter with only 54 transistors. Simulation results demonstrate that the proposed HFA-based 7:3 counter architecture consumes a power of 22.6 µW with a latency of 305 ps, showcasing significant improvements in power-delay-product compared to state-of-the-art designs. [ABSTRACT FROM AUTHOR]

Multi-body systems, like robotic mechanisms, may frequently encounter impacts while interacting with the environment. These non-linear impacts are often modeled as instantaneous events using discretized time impulse-based approaches. Although, momentum and energy conservation laws are sufficient to determine a solution for frictionless single point impulse problems, additional assumptions are required to solve simultaneous impacts. We propose a novel method (called QPSIM) to solve such simultaneous collision problems in links connected by frictionless joints by generalizing the quadratic programming (QP) based simultaneous impact model for unconstrained rigid bodies presented in the work of Rakshit and Chatterjee [35]. Two constraint equations are derived, which when included in the QP problem, results in a solution containing both collision impulses as well as joint reaction impulses and impulsive moments. Additional constraints depicting the physical laws of contact mechanics are also used in the simultaneous impact problem. A generalized matrix based derivation of the constraints and the impact model is presented which is applicable to both closed-loop and open-chain mechanisms. The solution is formed by the impulse set that minimizes the system’s net change in kinetic energy. QPSIM does not require an impulse propagation sequence to be assumed and is a computationally efficient alternative to the modeling of collisions in a force-based domain. Results for simultaneous collision scenarios in two planar and one spatial mechanisms are presented in this paper. In addition, this method is applied to solve a simultaneous impact problem on a top-hammer drill machine which is often used in mines and quarries. Moreover, the results are compared with results obtained using Linear Complementarity and ADAMS software simulations. The results show that QPSIM never results in an increase in kinetic energy and is able to predict contact separation between bodies having zero pre-impact relative velocity of approach. The solutions also exhibit an acceptable correlation with ADAMS software simulations. [ABSTRACT FROM AUTHOR]

Medical diagnosis can be severely hindered by distorted medical images, especially in the analysis of Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) images. Therefore, enhancing the accuracy of diagnostic imaging and inpainting damaged areas are essential for medical diagnosis. Over the past decade, image inpainting techniques have advanced due to deep learning and multimedia information. In this paper, we proposed a deep convolutional autoencoder network with improved parameters as a robust method for inpainting non-anatomical objects in MRI and CT images. Traditional approaches based on the exemplar methods are much less effective than deep learning methods in capturing high-level features. However, the inpainted regions would appear blurr and with global inconsistency. To handle the fuzzy problem, we enhanced the network model by introducing skip connections between mirrored layers in the encoder and decoder stacks. This allowed the generative process of the inpainting region to directly use the low-level feature information of the processed image. To provide both pixel-accurate and local-global contents consistency, the proposed model is trained with a combination of the typical pixel-wise reconstruction loss and two adversarial losses, which makes the inpainted output seem more realistic and consistent with its surrounding contexts. As a result, the proposed approach is much faster than existing methods while providing unprecedented qualitative and quantitative evaluation with a high inpainting inception score of 10.58, peak signal-to-noise ratio (PSNR) 52.44, structural similarity index (SSIM) 0.95, universal image quality index (UQI) 0.96, and mean squared error (MSE) 40.73 for CT and MRI images. This offers a promising avenue for enhancing image fidelity, potentially advancing clinical decision-making and patient care in neuroimaging practice. [ABSTRACT FROM AUTHOR]

One of the most popular south Indian languages in India is the Telugu language which is currently spoken by 84 million native Telugu speakers in Andhra Pradesh and Telangana. With the rapid growth of the Telugu digital content, the need for the automatic text summarizer is arisen to provide short text from huge text documents. Extractive text summarization model generates only significant sentences. Abstractive text summarization method requires more training time. In this paper, a novel hybrid model is proposed for generating text summaries by combining extractive and abstractive approach to reduce the training time. For extractive method TextRank algorithm is utilized and for abstractive method attention-based sequence to sequence model with bidirectional long short-term memory (Bi-LSTM) is utilized. Moreover, coverage mechanism is included into the proposed hybrid approach to reduce the repetition in summaries and to improve the quality of summaries. The performance of the proposed hybrid model is evaluated by the ROUGE toolkit in terms of F-measure, recall and precision. The results of the proposed model are compared with other existing models which shows that the proposed hybrid model outperforms other existing text summarization models for Telugu Language. [ABSTRACT FROM AUTHOR]

Optimization of scheduling problems that involve single or multiple machines with a multimodal objective function and linear or non-linear constraints are generally NP-Hard. The Artificial Bee Colony (ABC) algorithm is a metaheuristic proposed about eighteen years ago and has gained popularity in the swarm intelligence-based evolutionary computation approaches. Various scheduling requirements in diverse domains viz. Electric Vehicle charging, Operating Room, Nurse, Automatic Guided Vehicle (AGV), production, manufacturing, hydrothermal, Printed Circuit Board (PCB), and call centre scheduling are studied. The NP-Hard nature of these scheduling problems render exact methods incompetent for large problem instances thus requiring meta-heuristics such as ABC to produce feasible solutions in a reasonable computation time. The adaptation of ABC in these domains and the outcomes and performance of ABC are highlighted. Based on the case studies, it is found that the requirements of scheduling problems that would benefit from ABC are those that have a planning horizon requiring a near-optimal solution in a reasonably fast time when run on minimal computing capacity. Future works that would merit the application and enhancement of existing ABC techniques are proposed. The case studies presented in this paper motivate R&D Engineers and young researchers to apply ABC techniques of optimization and scheduling in different research topics for achieving energy and cost efficiency. [ABSTRACT FROM AUTHOR]

This paper is mainly composed of a comprehensive evaluation and discussion on the progressive collapse performances of outrigger braced reinforced concrete structures with transfer floor. The effects of transfer floor existence, combined use of transfer floor and outriggers, outrigger locations on load redistribution, plasticity development and robustness of structural systems under the sudden failure of the element(s) are the fundamental issues that shape the content of this study. Within this scope, six reinforced concrete systems with transfer floor and differently located outriggers are modelled in SAP2000 finite element program. The pushdown curves are compared through the nonlinear static analysis. For external and corner column cases, the maximum load factors versus vertical drift ratios are obtained in systems with outriggers located at the midheight (0.5H) and top level (H), especially. The differences in deformation characteristics of transfer floor-element interface can be properly limited by modifying outrigger locations and combinations. The hinging development can be much more effectively controlled with outriggers close to the transfer floor. The same tendency is also observed while the vertical spacing between outriggers is decreased, particularly until 0.65H. The results support that the optimized outrigger use develops an efficient alternate load paths under the abrupt element failure. [ABSTRACT FROM AUTHOR]

In this work, the time-fractional Tricomi equation is investigated via two efficient computational techniques. This equation is used to explain the nearly sonic speed gas dynamics phenomenon. The Homotopy perturbation transform technique, which is a combination of Laplace transform and a semi-analytical technique, and Homotopy analysis method are used to solve the time-fractional Tricomi equation. The existence and uniqueness of the solution is analyzed by using two different fixed-point theorems. Finally, the effectiveness of the proposed techniques is illustrated through two test examples by comparing the absolute error of proposed techniques with the existing techniques and the result achieved in this paper benefits (but not limited to) the gas flow dynamics. [ABSTRACT FROM AUTHOR]

Function generation synthesis of mechanisms can be considered as the design of correlation of crank angles and dead dead-center position design. These two problems have been clearly defined and solved separately. But some problems may require both correlation of crank angles and dead dead-center design at different configurations. Such problems are called mixed function generation problems. In this paper, an overview of these mixed function generation problems for the planar four-bar mechanism are given and the problems are solved analytically or semi-analytically. Except three of them, all presented mixed function generation problem formulations are novel. The solutions of all problems including three positions for the four-bar mechanism and the solution of a problem including four positions for a four-bar mechanism are addressed. All problems are first reduced to a univariate equation and a fast solution is found. Thus, link lengths can be found quickly by changing the problem definition problems, and several design iterations can be performed in a short time. Numerical solutions of all problems have been demonstrated using Excel. [ABSTRACT FROM AUTHOR]

Modal parameter estimation of a bridge with the vibration responses measured from an instrumented vehicle moving at a controlled speed is an active area of research. It is challenging to determine bridge natural frequencies and their associated mode shapes, as the measured output-only responses of an instrumented vehicle contain the desired dynamic responses of the bridge, along with the other confounding components related to vehicle dynamics, driving frequency component, and dynamics associated with the roughness profile of the road. These bridge responses are often masked by the dynamic responses associated with the vehicle, and road surface profile. Measurement noise components add to the existing problem of separating bridge frequency from various other said components. In this paper, an attempt has been made to extract bridge frequencies and mode shapes through the output-only responses collected from a traversing vehicle and using singular value decomposition (SVD) combined with the Teager-Kaiser energy operator (TKEO). Numerical investigations are made on the proposed SVD-TKEO-based modal identification technique in the presence of measurement noise. Parametric studies are conducted to investigate the influence of vehicle speed and road surface roughness on the quality of the identified bridge modal parameters using the proposed technique Numerical simulations carried out, show that the proposed SVD-TKEO-based algorithm performs well in identifying bridge mode shapes, even with relatively higher vehicle traveling speed, and handles even roughness of the road surface profile reasonably well. Lab-level experimental studies using vehicle bridge interaction setup, are also carried out using the SVD-based modal parameter estimation technique to explore its practical use. [ABSTRACT FROM AUTHOR]

Dynamic pricing is a crucial revenue management technique when product status changes over time. It can become more prominent if applied in conjunction with an inventory management strategy for deteriorating items. This paper presents a framework for dynamic pricing in a continuous time horizon for a dual-channel supply chain consisting of a manufacturer and a retailer. The manufacturer produces a deteriorating product and sells through direct and indirect retail channels, and both channels compete with each other over retail prices. The freshness of the product varies with time, and thus both channels invest in preservation technology, which further leads to carbon emissions. We derive an analytical solution to the dual-channel pricing model. Furthermore, the case of single-channel pricing has been investigated to study and compare its pricing strategy with the dual-channel pricing strategy. Lastly, a numerical illustration is presented to study the impact of key parameters on optimal decisions through sensitivity analysis. We provide managerial recommendations in various scenarios like an increase in competition, the shift of consumer preference between channels and fluctuation in demand. [ABSTRACT FROM AUTHOR]

Safe and efficient navigation is critical for a mobile robot in a highly constrained workspace. Autonomous navigation is to be performed safely and robustly in the environment map with obstacles of various geometric shapes, sizes and colors positioned at random locations. In this paper, we present an approach to perform autonomous navigation by detecting the obstacles in the map and by generating auxiliary collision-free waypoints in obstacle-free space map. In achieving this, the object detection is done using SSDMobileNetV2 model and auxiliary collision-free navigation waypoints are generated using the Deepway neural network model. Further, the RRT path planner is applied to analyze the waypoints generated and to find the a global path between start and goal locations. An optimal local path is achieved using the A* path planner. Extensive simulations of various scenarios are performed and the proposed model is evaluated. The results reveal that the proposed model achieves significant improvements in terms of time, distance and F1-score. [ABSTRACT FROM AUTHOR]

This paper presents a novel method for measuring flow rates in microchannels based on electrolytic bubble generation and electrochemical resistance measurement. The method exploits the generation of gas bubbles by electrolysis of ionic fluid at the surface of electrodes positioned within the microchannel. The flow rate is quantified by measuring the electrical resistance of the electrolyte using electrodes in inter-digitated form. By analysing the bubble frequency and size, the variation in the resistance is investigated and as a result the flow rate can be determined with high accuracy and precision. The proposed method is suitable for a wide range of flow rates, and can be easily integrated into microfluidic systems. We demonstrate the feasibility and performance of the method through experiments using 0.1M NaCl over a range of flow rates in a microchannel with different geometries. Flow measurements are made in range 0–200 μl/min with a measurement sensitivity of 3.17 Ω /(μL/min) and RSD < 15%. 3 σ resolution of the sensor is 12.5 μL/min. The rise in fluid temperature is observed to be less than 5 °C at all times. The proposed method has potential applications for on-chip detection in chemical synthesis, drug development and biomedical devices and is easy to implement and scalable. [ABSTRACT FROM AUTHOR]

Stepper motors are synchronous electric actuators with incremental displacement that can be controlled in open loop in position or speed. Unfortunately, the rotor oscillations that characterize stepper motors are a major handicap that limits the use of this type of actuator in precision industrial applications and especially in biomedical systems. Improving motor drive performance is challenging due to the presence of uncertainty in system parameters and large load variations. To overcome these problems and the shortcomings of conventional control approaches, a new control concept based on fuzzy logic is developed. To this purpose, this paper proposes a fuzzy logic concept (FLC) for damping rotor oscillations of stepper actuator devoted to an Electrical Syringe Pump application. The FLC membership functions and rules are designed with value normalization that allows the developed controller able to be flexible when applied to a wide range of applications. The proposed FLC is numerically validated. Critical testing scenarios are employed including motor inertia variation, supply voltage variation, fluid friction variation and for different loads. Moreover, thanks to its normalized design, the proposed FLC is not limited to the studied biomedical applications, but can be applied to other application systems. [ABSTRACT FROM AUTHOR]

Near-fault ground motions (NFGM) may have a significant component of the long period velocity pulse (LPVP) due to the directivity effect. The structures subjected to such ground motions are prone to experience large displacements. In this paper, the damage potential of such motions is compared with NFGM (without LPVP) and far-field motions in terms of seismic demand (inter-storey drift and inelastic displacement). Due to the lack of site-specific recorded NFGM, the synthetic ground motions are generated and used in this study. For this purpose, first the bedrock motions are obtained through stochastic simulation approach in which the Specific Barrier Model (SBM) is used as source spectrum and then these motions are transferred to the ground surface using one-dimensional ground response analysis. In order to obtain the NFGM with pulse, the bedrock motions are superimposed with the LPVPs and then transferred to the ground surface. To illustrate, the case of a ten-storey reinforced concrete (RC) building is considered in Delhi region (India) which falls under the seismic zone-IV. The main finding of this study is the observation that the NFGM with LPVP impose almost double seismic demand compared to the NFGM without LPVP, specially for the structures lying in the velocity-region of the response spectrum. In this study, the effect of depth of bedrock on seismic demand is highlighted and recommended to be included in the design seismic demand of NFGM. [ABSTRACT FROM AUTHOR]

The current European Standard (EN 1994-1-1: Eurocode 4) put forth a reduction factor for Solid Composite Beam (SCB) with Class 1 and 2 sections for the design moment of resistance for sagging bending. This paper presents the analytical study on the behavior of Cellular Composite Beam (CCB) and proposes the reduction factor for the ultimate moment capacity of CCB sections. A moment-curvature program based on the strain compatibility method has been developed and used to examine the behavior of CCB made of S355, S460, and hybrid strength steel sections with different geometries. The program involves elastoplastic analysis since it is crucial to explore how the cellularity of the composite sections increases their curvature ductility, flexural resistance, and material utilization under high strain. The developed program has been validated against FE results, available test data, and ACB+ software solutions. A parametric study has been carried out to determine the effect of steel grade, concrete grade, effective width and depth of the slab, and varying sizes of a web opening on CCB sections. The Eurocode 4 design guidelines were used to determine the bending resistance of CCB for S355, S460, and hybrid-strength steel sections. The parametric study showed that high-strength concrete with a wider effective slab and enhanced depth sections with the lowest web opening causes CCB sections to have a higher ultimate moment and ultimate curvature. Comparing the hybrid CCB section to the regular and high-strength sections also showcases a significant enhancement in ductility and moment capacity. [ABSTRACT FROM AUTHOR]

This paper studies a mathematical model of the phase transition process as a moving boundary problem (MBP). An equation describing the temperature-dependent thermal conductivity and Robin-type boundary condition at the fixed boundary is used in the model. In order to solve the considered MBP, we propose an iterative-based Keller box method (KBM) for the numerical approximation and boundary immobilization method (BIM) to immobilize the moving boundary. In addition, KBM incorporates nonlinearities in thermal conductivity and boundary conditions. We study the stability and consistency and found out that the scheme is second-order accurate in both time and space. A specific case having a similarity solution has been considered to validate the numerical scheme. Our numerical results show that the KBM is in good agreement with the similarity solution. In addition, the rate of convergence of the KBM scheme is two. Different parameters and temperature-dependent thermal conductivity are studied to determine how these affect the position of the moving boundary. [ABSTRACT FROM AUTHOR]

This paper reports experimental investigations on cold plates made from Low-Temperature Co-fired Ceramic (LTCC) technology for liquid cooling of supercomputer microprocessors. LTCC, a ceramic substrate-based technology with lightweight and ease of fabrication for miniaturization of cooling devices, can be a potential alternative to the existing copper cold plates for future three-dimensional stacked chip architectures. LTCC cold plates were fabricated using ceramic substrates whose thermal conductivity was enhanced using thermal vias. They were embedded with microchannels for liquid with different flow configurations. Their thermal performance is compared against copper cold plates. Deionized (DI) water is used as a coolant. Pressure drop and thermal resistance across different cold plates are measured as per water-cooled data center standards (W3 and W4 class). Obtained experimental results show that the tested LTCC cold plates can be used to cool supercomputer processors. It is concluded that LTCC cold plates can be a potential alternative for existing copper cold plates. [ABSTRACT FROM AUTHOR]

Some percentage of nano polymer has been introduced in a cementitious material as a micro reinforcement to control the mechanical properties of cementitious materials. In this paper, graphene nanoplatelets (GNPs) are consumed to enhance the mechanical properties and reduce the crack propagation of cementitious material. Graphene nanoplatelets are used as reinforcement by 0.01%, 0.02%, 0.04%, 0.08%, 0.1%, 0.2%, and 0.3% of the Portland pozzolana cement's weight. The nanoparticles are scattered using a surfactant with an ultrasonic probe sonicator and cast in different mold types. All individual sets are tested in a 3-point flexure bending strength test. As a result, properties like flexural strength, Compression Strength, Young's Modulus, Toughness, and strain capacity are estimated. SEM and TEM are used to understand proper bonding and the sonication time. Increasing the percentage of GNPs, flexural strength improved by 28% to 84% compared to cementitious material, enhancing its toughness and young modulus. The XRD results are used to analyze the phase identification, crystalline size, crystallinity index (CI), and d-spacing for all samples of nano-cementitious materials. FTIR results are also introduced in this paper to identify the board peaks that facilitate the functional group's electron delocalization pattern. After completing this study, the microscopic and mechanical analysis may offer a key reference for graphene nanoplatelet cement composites, which can lift their strength, constancy, integrity, density and reinforce the composite microstructure. [ABSTRACT FROM AUTHOR]

Plantlet is a new variant of Sprout lightweight stream cipher. It uses 61 bit LFSR and 40 bit NFSR. This paper presents a study of Plantlet stream cipher with probability based approach for making algebraic attack on Plantlet. In this paper, we have used low degree multiple of Boolean function to apply algebraic attack. The low degree multiple of Boolean function is multiplied to output keystream function in order to get output equation such that it consists of only LFSR state variables. These equations are further solved to find secret key and internal states. In this manner, the complexity of solving equations is reduced. In this paper, it takes 2 60.99 Plantlet encryptions to solve system of equations. Commonly, standard algebraic attack and fast algebraic attack have been applied on various stream ciphers. However, the probabilistic algebraic attack has been implemented on Grain family of stream ciphers but not on Plantlet. The probabilistic algebraic attack can be applied on other stream ciphers. [ABSTRACT FROM AUTHOR]

The primary objective of grids is to provide uninterrupted and high-quality electrical energy. Synchronous generators play an important role in supplying uninterrupted and high-quality electrical energy to the grid. Synchronous generators achieve this goal with load frequency control (LFC) and automatic voltage regulator (AVR) systems. LFC regulates the rotor speed of the synchronous generator, i.e., the frequency at the connection point, while AVR regulates the terminal voltage of the synchronous generator. Both systems require a controller to operate properly, and their parameters should be properly selected using analytical or numerical methods to achieve the best controller performance. The controllers of the AVR-LFC system are optimized in this paper using a recently introduced metaheuristic method known as the Mayfly algorithm. Because objective function selection is critical in optimization processes, a novel objective function for the AVR-LFC system is proposed in this study. The proposed objective function is compared to well-known objective functions (performance metrics) such as integral square error, integral absolute error, integral time square error, and integral time absolute error in the literature. As a result of this comparison in the time domain analysis, the success of the designed objective function is demonstrated. In the rest of the paper, robustness, and random load/voltage change analysis for the AVR-LFC system are considered using the FOPID controller. Also, the frequency-dependent load analysis is investigated in this study. The success of the optimal FOPID controller designed with the proposed objective function is proved in detail in simulations. [ABSTRACT FROM AUTHOR]

The modeling and control of epidemics, such as the novel Coronavirus, have become crucial on a global scale, for effective management of epidemic situations. This paper is focused on using the mean field approach for modeling and control of epidemics. The mean field approach is an effective alternative to the classical approach of using continuous time Markov decision process (CTMDP) models, which suffer from the curse of dimensionality and entail knowledge of global state information. The mean field approach captures the collective behavior of a dynamic system consisting of numerous interacting nodes representing individuals in the population. The objectives of this paper are twofold: (a) to provide an overview of the mean field approach to epidemic modeling and control, and (b) to present recent advances in this area. Emphasizing the importance of containing and suppressing epidemic spread through non-pharmaceutical interventions, the paper highlights the need to minimize loss of lives, reduce suffering, and alleviate the burden on the public healthcare system. A potential challenge here is the presence of a section of the population who act on their free will and deviate from recommended best practices, which could lead to a potential public health crisis. Motivated by this, the paper explores two specific threads to modeling and control. The first thread assumes that individual nodes comply with a socially optimal control policy mandated by a regulatory authority. The second thread allows for independent and strategic behavior by the individual nodes, modeled as a mean field game, where the strategies of rational agents are based on mean field Nash equilibria. The paper begins by discussing the modeling of epidemics using an extended SIVR (Susceptible-Infected-Vaccinated-Recovered) compartmental model, accompanied by an illustrative example. Next, a literature review is provided, focusing on the mean field approach for socially optimal control of epidemics and how a regulatory authority can effectively contain the spread. Subsequently, the paper presents an update on the use of mean field game-based approaches in studying epidemic spread and control. Finally, future research directions in this important area are discussed. [ABSTRACT FROM AUTHOR]

This paper reports on new research that: characterizes the influence of regenerative lateral forces on the stability of metal circular sawing; describes the role of process damping in potentially stabilizing the sawing process; and investigates the role that distributed and lubricated guides play in a sawing process prone to regenerative instabilities. We model the saw as a rotating disc using the Von Kármán plate theory. Equations of motion are derived using the Hamilton’s principle. Guides are modelled as being distributed and properties of the fluid are modelled to be a function of the guide size and its placement relative to the saw. The regenerative and process damping effects are incorporated based on other similar models for milling processes. Our model-based analysis suggests that: regenerative instabilities are characterized by a growth in the real part of the eigenvalue of the system; clearance between the guide and the rotating saw and the guide’s circumferential placement with respect to the cutting zone both influence the severity and speed regions of instabilities; material being cut and changing cutting engagements do not significantly influence the region of instabilities; and that process damping can help stabilize an otherwise unstable process. Though models need to be validated, our observations can still instruct the design of stable guided metal sawing processes in industries. [ABSTRACT FROM AUTHOR]

The present study investigates unsteady wake dynamics in flow past an oscillating cylinder. A two-dimensional computational analysis is undertaken for flow past a sinusoidally oscillating cylinder. Operating parameters like Reynolds number, forcing frequency, amplitude, and wavelength are systematically varied, and their effect on wake dynamics is investigated. Lift and drag coefficients are plotted with cylinder position to characterize the flow. The flow field is analyzed using Proper Orthogonal Decomposition (POD). POD mode shapes and Power Spectral Density (PSD) plots characterize the flow response to cylinder oscillations. The effect of frequency ratio is examined in achieving synchronized vortex shedding. Previous studies focus on two extremes- the cylinder is either stationary or oscillating with perfect phase-locking. Flow past an oscillating cylinder where Karman and forcing frequencies compete for dominance is rarely reported. This paper considers such a scenario and demonstrates how POD can identify coherent structures, their significance, and associated frequencies. Further, non-symmetric vortex shedding, which is not a common observation, is captured and discussed. Large amplitude and large wavelength regimes are investigated, which remained unexplored in previous research. Coherent structures associated with those regimes are identified. [ABSTRACT FROM AUTHOR]

Recently, the alkalization of various materials for solidifying vulnerable soil has become increasingly prevalent to improve their structural integrity and strength properties. However, the characterization of laterite soil solidified by alkalizing strong electrolytes has been limited. This research paper presents an innovative way of utilizing an alkaline activator and bischofite (MgCl2·6H2O) to initiate the activation of silica and alumina constituents and polymerization for the physio-chemical characterization of laterite soil and determine the optimal design mix. Standard compaction and uniaxial strength (UCS) were assessed for mechanical features, and mechanisms contributing to solidification were assessed using SEM, EDS, and FTIR. The alkalization of bischofite has significantly altered the mechanical characteristics of the sample. The UCS test findings at ambient room temperature revealed that a sample containing an alkaline activator proportion of 0.75, an activator-to-bischofite proportion of 0.9, and a 5% bischofite by dry soil weight of soil is the optimal mix to ameliorate the potency of the laterite soil. The development of hydroxyl groups on kaolinite edges and cation replacement decreased pH with the curing period, promoting structural modification in physiochemical analysis. The solidification methods created a bonding gel of hydrated magnesium silicate (M–S–H) compounds, as shown by SEM micrographs and EDS spectra. Additionally, the FTIR finding affirmed the formation of magnesium hydration products in the spectral range of 1600 to 450 cm−1 with silicate, aluminum, and magnesium chain polymerization evolution. Finally, the study demonstrated the potential of bischofite-alkalization to modify the physiochemical and micro-structural features of weak laterite soil to be utilized in various construction projects. [ABSTRACT FROM AUTHOR]

This study investigated dual-fuel engine performance at high altitude. The test engine was modified from a high-pressure common-rail diesel engine and fuelled with diesel and natural gas. The impact of fuel substitution rate, which is the most critical calibration parameter of dual-fuel engines, on the fuel economy and emissions was studied. Pilot diesel fuel and natural gas flow rates were optimized to minimize fuel consumption while ensuring good combustion stability, emissions, and durability. The advantages of full-load power capability, fuel consumption, and emissions of the dual-fuel engine were revealed with a comparison to the pure diesel engine. This paper also addresses the performance of the dual-fuel engine at high altitudes and reveals its advantages. With an in-cylinder pressure analysis, the test results showed that the dual-fuel engine could achieve higher brake mean effective pressure (BMEP) in a wide range of engine speed compared to the pure diesel engine. When compared at the same operating condition, the dual-fuel engine generally produced much less fuel consumption and emissions, especially at high loads. [ABSTRACT FROM AUTHOR]

Microscale mesh patterns on surfaces are useful in several domains of application including surface texturing, microfluidics, biomimicking, and so on. Currently available techniques for fabrication of smooth microscale mesh patterns, based on MEMS technology or two photon 3D printing are complex, time-consuming, expensive, and lack scalability. Scalable manufacturing of array and fractal-like geometry via innovative concept of ‘shaping the fluid and retaining the shapes’ has been proposed recently. In this paper, we extend this concept by introducing evaporating polymer suspension in place of non-evaporating ceramic particle suspension, used previously. Fabrication process involves squeezing (with sealed holes) of the polymer solution (in a volatile solvent) between two cell plates, having an array of drilled holes, followed by parallel lifting (with the unsealed holes) of cell plates. Lifting induces a pressure drop within the stretched fluid film, dragging in the surrounding air from each hole, reorganizing the fluid into square or hexagonal mesh patterns based on the location of the holes. The volatile nature of the suspension allows self-curing of the structure that eliminates the post-curing step. This mesh fabrication process is demonstrated to be scalable in terms of the mesh dimensions (controlled by source holes pitch) and mesh density (controlled by the number of source holes on the cell plates). The fabricated mesh pattern is further used in the soft lithography step to obtain a vascular microchannel mesh replica in PDMS for developing the proposed Concentration Gradient Generator (CGG) on chip. The source and sink are punched over the PDMS to prepare the proposed diffusion-based static CGG devices. Finally, we experimentally demonstrated the stability of the concentration gradient in the proposed square mesh CGG device. The results of experiments were compared to those obtained using finite element analysis-based simulation software COMSOL Multiphysics. We further tweaked the device design parameters in simulated parametric analysis to demonstrate the flexibility of CGG for various bio-engineering applications. In summary, this work establishes a novel, scalable, low-cost, time-efficient, and lithography-less fabrication pathway for fabrication of mesh like geometries along with demonstration of their use for CGG applications. [ABSTRACT FROM AUTHOR]

Passive direct methanol fuel cells (DMFC) are most suitable for charging of portable electronic devices. Fuel and oxidant are supplied through diffusion and natural convection processes on the anode and cathode sides of the passive DMFC, respectively. This paper presents the details of experimental studies on the use of different anodic fuels i.e., ethanol, 1-propanol, 2-propanol, methanol in an alcoholic fuel cell. And also, the effect of adding these alcohols as additives to the methanol fuel on the performance of a passive DMFC is presented. For each one of the alcoholic fuels, the concentration of the fuel was varied from 0.5 M to 5 M, and the impact of fuel concentration on the performance of the cell was studied. Similarly, with methanol along with the other alcohol additives as the fuel in the passive DMFC, the additives concentration was varied from 0.5 M to 2.5 M insteps of 0.5 M and the methanol concentration was varied from 1 M to 5 M in steps of 1 M. The experimental results showed that among the anodic alcoholic fuels, 2-propanol generated the peak power density of 4.416 mW cm−2 at 4 M concentration. Similarly, it was also observed that among all the additives, the 2-propanol at 2 M concentration along with methanol at 4 M concentration produced the maximum power density. [ABSTRACT FROM AUTHOR]

This paper presents a dual-band printed monopole antenna backed with an electromagnetic band-gap (EBG) array for LTE, WLAN, Wi-MAX, and ISM band applications. The antenna is comprised of a T-shaped monopole, 50 Ω microstrip feed line, and a rectangular-shaped partial ground plane. The printed monopole antenna is supported by a 6 × 6 array of EBG unit cells, with each unit cell composed of square and circular rings, resulting in a wide impedance bandwidth and improved gain. The EBG-backed printed monopole antenna with partial ground plane offers an impedance bandwidth of 57.8% (1.6–2.9 GHz) and a maximum radiation efficiency of 95.4% with a peak gain of 6.9 dB in the first band, and an impedance bandwidth of 53.24% (3.39–5.85 GHz) and a maximum radiation efficiency of 95.2% with a peak gain of 8.7 dB in the second band. The proposed monopole antenna design is miniaturised, has less design complexity, and does not require vias for EBG realisation. [ABSTRACT FROM AUTHOR]

The solution of the Poisson equation raised from large-scale problems requires iterative techniques. Multilevel and Krylov subspace methods have been proven to be the most efficient among various iterative methods. Recently, the scheduled relaxation Jacobi technique has been developed, which can be used as a stand-alone iterative solver as well as a preconditioner to the Krylov subspace methods. The relaxed Jacobi (RJ) method has also been implemented as a smoother in the multigrid method, with no-post smoothening. Here, the focus is to test the performance of relaxed Jacobi when applied to the large scale Poisson problems. Multigrid methods with both post-smoothening and pre-smoothening operations have been conducted in this paper. The methodology is applied to a rectangular domain using structured Cartesian grids. Also, multigrid methods with relaxed Jacobi smoothers are used as preconditioners to Krylov subspace solvers, and their performances are compared with the red-black Gauss-Seidel smoothers. Similar to the results in the literature, RJ smoothers to multigrid techniques provide better results than Gauss-Seidel smoothers when no-post smoothening operations are carried out. However, the use of post-smoothening operations changed the entire dynamic of the RJ smoothers. [ABSTRACT FROM AUTHOR]

Underwater drilling and blasting techniques have been developed to overcome the challenges posed by various subaquatic operations, including marine construction, oil and gas exploration, and underwater mining, demolition, dredging and excavation, seismic surveys and marine research. The drilling operation is followed by underwater blasting, which involves the creation of boreholes in submerged surfaces, such as sea beds or riverbeds. Specialized drilling equipment is utilized, which can operate in aquatic environments. To ensure efficient and reliable performance, the drilling equipment is designed to withstand the pressures and corrosive nature of seawater. Once the desired depth is reached, underwater blasting is utilized to break the rock or seabed. The primary objective of blasting is to loosen the substrate and create a cavity for subsequent operations. Safety is a crucial factor in underwater drilling and blasting operations. To safeguard personnel involved and prevent accidents during drilling and blasting activities, strict safety measures are implemented. In addition to human safety, precautions are taken to minimize the environmental impacts of underwater drilling and blasting, including measures to prevent pollution, protect marine life, and preserve the underwater ecosystem. In this article, the core elements of underwater drilling and blasting operations are outlined. Despite notable progress in this domain, the paper highlights the enduring constraints and obstacles, underscoring the need for continued investigation and understanding. [ABSTRACT FROM AUTHOR]

Sills and baffles are appurtenances used to stabilize hydraulic jump in a stilling basin. The force acting on these appurtenances are characterized by the drag coefficient (CD). This paper describes experimental methods carried out in a rectangular channel to analyze the drag characteristics of sill and baffles in free (unsubmerged) and submerged hydraulic jumps. The sills and baffles were designed as per the USBR type III stilling basin guidelines. A calibrated loadcell connected to an Arduino board was used to measure the drag force. Errors in measurements are limited to 1%. The drag co-efficient was obtained for different Froude numbers (F1=U1/√gy1) pertaining to strong jump (4.5–9) for different relative position of sills (xS/y2) and baffles (xb/y2) from the nozzle of the sluice gate. Both forced (unsubmerged) and submerged jumps were investigated. It is seen that the drag coefficient of appurtenances in submerged jumps were lower than those in free jumps. This may be attributed to the reduction in wake size in submerged jumps. Comparisons of the experimental results of the sill with the previous theoretical studies are reasonable. [ABSTRACT FROM AUTHOR]

In this paper, we have proposed the precise model of coaxial TGVs (CTGVs) which consists of ground-signal signal-ground (GSSG) TGVs. An equivalent electrical model of CTGVs is established and the partial element equivalent circuit (PEEC) technique is used to extract the frequency-dependent impedance parameters. In CTGVs, multi-walled carbon nanotubes (MWCNT) and copper is used as filler material in inner and outer layer. Resistance and inductance of CTGVs is calculated using the PEEC technique for different filler materials. The insertion loss (S21) of CTGVs is determined using the HFSS simulations and is compared analytically in differential mode configurations. S21 is calculated for various geometrical parameters of MWCNT-based CTGVs such as diameter of TGV, pitch between CTGV pair, as well as material properties such as permittivity of SiO2 and benzocyclobutene (BCB) polymers. It is established that MWCNT based CTGV shows improved insertion loss because the conductivity of MWCNT is higher in comparison to copper. [ABSTRACT FROM AUTHOR]

FinFETs ensured the continuation of semiconductor industry with reliable, high performance and low power devices fabricated at sub-100 nm technology nodes. These FinFETs are able to suppress the Short Channel Effects quite effectively while decreasing the leakage currents. Below 22 nm gate lengths, the SCEs resurfaced. To suppress these effects, the thickness of the gate oxide reduced. As the gate oxide thickness reached below 2 nm, the leakage currents started increasing again. Thus arose the need for replacing SiO2 with high permittivity dielectric materials like Zirconium Dioxide, Hafnium Oxide, Aluminum Oxide and Silicon Nitrate. Research also suggested the use of Multi Fin architectures to enhance the drain currents. The focus of this paper is to develop multiple fin 08 nm gate length SOI FinFETs having three fin architecture where the gate oxide of each fin consists of a stacked combination of 0.5 nm of high-k dielectrics atop another layer of 0.5 nm of SiO2 to reduce the leakage currents and other SCEs. The use of 3-Fin structures significantly enhances the drain current leading to higher switching speeds for faster CMOS fabrication and optimized device performance towards semiconductor industry. [ABSTRACT FROM AUTHOR]

The main objective of this paper is to design a Frequency Selective Surface (FSS) generating multi stop-band and having the property of a large scanning angle from a mixed polarization insensitivity structure for GPS, PCS, WiFi, IEEE S-band radar, 5G mobile phones, (802.11j) WLAN applications. To fulfill the objective, a hexa band-stop FSS has been developed using a novel symmetrical structure with a compact dimension of 0.095 λ 0 × 0.095 λ 0 , where λ 0 is the wavelength of free space at 1st resonant frequency. The proposed FSS covers a broad scanning angle of 60 0 for shielding electromagnetic wave radiation and smaller resonant frequency ratio ( f n + 1 / f n ) to improve compactness under TE and TM polarizations. The six achieved stop frequency bands are 1.36 GHz–1.56 GHz, 1.66 GHz–1.99 GHz, 2.34 GHz–2.46 GHz, 3.08 GHz–3.42 GHz, 3.6 GHz–4.12 GHz and 4.5 GHz–5 GHz for improving shielding performance. [ABSTRACT FROM AUTHOR]

In this paper, we propose a unified approach for denoising and super-resolution of document images. The approach is a one shot unpaired technique where a single unpaired example is used as reference for training a SinGAN (Shaham et al., in: Proceedings of the IEEE/CVF international conference on computer vision, 2019) model. The training is carried out in 2 steps. First we use a clean reference image to train a SinGAN to learn the characteristics of the clean image. Then we perform super resolution and denoising of given test image using another SinGAN. Our unique formulation of the loss function helps in this task by prompting the generated images to have characteristics similar to the reference clean image. We conduct experiments on publicly available datasets (Kaggle Dirty Documents Images and DIBCO) and obtain promising results. We also evaluate the performance of our model for OCR and obtain a higher recognition rate compared to competing methods. [ABSTRACT FROM AUTHOR]

Handwriting-based technologies have progressed significantly over the years. Scientists have worked beyond just recognizing pieces of plain text from paper. With archaeological advancements, discovery of ancient documents has not been as scarce as it was in the past. However, such documents are discovered in perfect condition once in a blue-moon. They are often subjected to degradation due to the perils of time and understanding them requires skilled manpower which is not easy to find. Here, an automated system is proposed for this task. The proposed system uses a new CNN-based framework to analyze the macro and micro features of an image to recognize the text. Experiments are performed with over 250K historical images of numerals from a publicly available dataset and a highest accuracy of 99.68% is obtained. The data is further subjected to different type of noises and distortions. A novel technique is used to introduce synthesized degradation in the documents. The system performs steadily in all these experimental scenarios. Comparative analysis indicates that our results are higher than the reported works and other standard techniques. [ABSTRACT FROM AUTHOR]

Motion information from image sequences (videos) plays a key role in solving a number of real-world problems such as surveillance, traffic management, fire identification, weather prediction, and COVID-19 detection, etc. Generally, this motion is estimated in terms of optical flow between two consecutive image frames. Optical flow is a 2D vector field that illustrates object motion behavior. This paper presents a nonlinear fractional order variational model for estimating optical flow. The objective of this work is to provide dense and discontinuity preserving optical flow for different spectra and make the model robust against outliers. In particular, the presented model generalizes the integer order variational models for fractional order (0, 1). For this purpose, the proposed model is formulated with the help of Charbonnier norm and Caputo fractional derivative. Charbonnier norm is nonlinear in nature, which makes the model robust against noise and outliers, whereas Caputo fractional derivatives are well-capable to deal with discontinuous functions such as images, and therefore, preserve motion discontinuities. The Caputo derivative also manifests long-term memory effect and allows to choose the optimal value of the fractional order that corresponds to a stable solution. The numerical implementation of the formulated variational functional is performed by discretizing the fractional derivative using the Grünwald–Letnikov derivative. The resulting system of equations is solved using multi-variable fixed point iteration scheme. The entire framework is embedded in coarse-to-fine warping strategy, which helps in finding the global extremal. The experimental results are carried out on 20 different application oriented datasets such as fire and smoke, fluid, CXR, etc. The performance of the model is tested using different error measures and demonstrated against several outliers. Error concentration is shown through 3D histograms. The edge preserving nature is also realized through intensity distribution in RGB color channels. A detailed convergence analysis is also provided for the presented model. The validity of the proposed model is also verified through comparisons with other existing models. [ABSTRACT FROM AUTHOR]

This paper presents a technique for repairing errors in GPU kernels written in CUDA or OpenCL due to data races and barrier divergence. Our novel extension to prior work can also remove barriers that are deemed unnecessary for correctness. We implement these ideas in our tool called GPURepair, which uses GPUVerify as the verification oracle for GPU kernels. We also extend GPUVerify to support CUDA Cooperative Groups, allowing GPURepair to suggest inter-block synchronization for repairing a CUDA kernel if deemed necessary. To the best of our knowledge, GPURepair is the only tool that can propose a fix for intra-block data races and barrier divergence errors for both CUDA and OpenCL kernels. It is also the only tool that can propose fixes for inter-block data races in CUDA kernels. We perform extensive experiments on about 750 kernels and provide a comparison with prior work. We demonstrate the superiority of GPURepair through its capability to fix more kernels and its unique ability to remove redundant barriers and handle inter-block data races. We have also enhanced the initial version of GPURepair to support incremental solving during the repair process. This enhancement improves the performance of GPURepair by about 25% for the test suite that we have used. [ABSTRACT FROM AUTHOR]