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Medical images are treated as sensitive as it carries patients' confidential information and hence must be protected from unauthorized access. So, a strong encryption mechanism is a primary criterion to transmit these images over the internet to protect them from intruders. In many existing algorithms, noise affection in the extracted images is high, hence not suitable for medical data encryption. Here, we present a new method using phase grating to multiplex as well as encrypting 32 cross-sectional CT scan images (slices) in a single canvas for optimization of storage space and improvement of security. The entire process is divided into a few steps. Before transmission, the main canvas is encrypted with the help of a random phase matrix. The main canvas is further encrypted by the transposition method to enhance security. After decryption, inverse Fourier transform is applied at the proper location of the decrypted canvas to extract the images from the spectra. Quality is measured with peak-signal-to-noise ratio and correlation coefficient methods. Here, it is greater than 38 and the correlation coefficient is close to 1 for all images, thereby indicating of good quality of extracted images. The effect of three common cyber-attacks (viz. known-plaintext attack, chosen-plaintext attack, and chosen-ciphertext attack) is also presented here. The correlation coefficient during cyber-attacks is found to be close to zero, which implies the robustness of the algorithm against cyber-attacks. Finally, a comparison with existing techniques shows the effectiveness of the proposed method.

The term “frozen shoulder” was first introduced by Codman in 1934. He described a painful shoulder condition of insidious onset that was associated with stiffness and difficulty sleeping on the affected side. Codman also identified the marked reduction in forward elevation and external rotation that are the hallmarks of the disease (Richard Dias et al, 2005). Brian Mulligan’s concept of Mobilization with Movement (MWM) is a natural continuance of the progression in the development of manual therapy from active stretching exercise to therapist applied passive physiological movement to passive accessory mobilization technique. (Deepali Rathod et al, 2019). Aims and Objectives: To evaluate the effectiveness of Mulligan Therapy along with conventional on Pain, ROM, Proprioception and muscle strength in patients with diabetic frozen shoulder. Methodology: 31 Patients were treated with Mulligan Therapy, Stabilization Exercise and Moist Heat Therapy. All the patients were selected after informed consent. These patients were interviewed by direct method. The patients were assessed in 0 (zero) week and reassessed in 4 (four) weeks and 8 (eight) weeks of treatment programme. Every 0 week 4 weeks and 8 weeks of treatment programme, pain, ROM, shoulder strength, shoulder Proprioception & disability were recorded.

This study involved a commercial hot-rolled dual-phase (DP) steel consisting of martensite (~10 pct) and ferrite phases. The harder lath martensite was located at the grain boundaries and triple junctions of the equiaxed ferrite grains. Tempering and high-pressure torsion (HPT) were used to alter the phase hardness differential ∆H (where $$ \Delta H = H_{\text{Martensite}} - H_{\text{Ferrite}} $$ ) of the DP. The relationship between ∆H and non-uniform elongation, eNU, or post-necking ductility under tensile deformation, was then explored. Tempering softened predominantly the martensite, while HPT increased the ferrite hardness. Both led to a reduction in ∆H. A drop in ∆H in the tempered DP resulted in a steady increase and eventual saturation in eNU. On the other hand, a ∆H decrease in the HPT specimens showed an initial increase in eNU followed by a drop. Strain analysis, with optical digital image correlation during tensile deformation of the tempered DP samples, clearly related the formation of strain localization with ∆H. In particular, severity of strain localization during necking scaled linearly with ∆H. This study thus brought out a potential relationship among the phase hardness differential (∆H), severity of strain localizations and post-necking ductility (eNU).

The efficiencies of jet turbine engines are limited in part by the high-temperature properties of Ni-based superalloys utilized within turbine blades. Although Mo–Si–B alloys exhibit promising high-temperature properties, traditional materials development approaches relying extensively upon costly trial-and-error experiments inhibit the adoption rate of new materials. The present research seeks to address this problem by developing and demonstrating a computational materials design framework for the design of Mo-Si-B alloys for gas turbine blade applications. The developed framework utilizes: (1) finite element simulations of 280 random microstructure instantiations to predict microstructure- and temperature-dependent yield strength and fracture toughness and their uncertainties; (2) analytical models to predict stresses due to turbine blade rotation; and (3) the inductive design exploration method (IDEM) to determine robust feasible domains of input and intermediate design variables. IDEM considers three input design variables (i.e., operating temperatures of 1273 K and 1473 K, volume fraction of the Molybdenum solid solution phase 0.45 ≤ vMoSS ≤ 0.75, and volume fraction of T2 intermetallic phase 0.125 ≤ vT2 ≤ 0.275) and three intermediate design variables (i.e., yield strength, fracture toughness, and density). Results indicate a maximum feasible temperature of approximately 1295 K at vMoSS and vT2 of approximately 0.45 and 0.18, respectively. This work is significant in that it demonstrates the design of Mo-Si-B alloys for high-temperature blades for aerospace applications, thus providing a means to increase efficiencies and reduce greenhouse gas emissions.

Nowadays computer network is a blessing to modern society due to its various features which are especially suitable for cloud computing, teleconferencing etc. A lot of information transmission is the basic criteria of these applications. Unfortunately, cyber attackers are active everywhere and they try to misuse this facility. Therefore, this information should be transmitted securely. Moreover, this information should be compressed for proper optimization of bandwidth of the transmitted medium. In this communication, we propose a novel method for compression and encryption of medical images using optical process which is suitable for secure teleconferencing. For our research work, we have used sinusoidal amplitude grating. Medical images are modulated with the help of high frequency grating frequency and variable orientation angle. As a result of modulation, three spectrums have been generated for each image. One spectrum is the FT of the image (center spectrum) and other two are sidebands. Out of these two sidebands, only one sideband of each image is taken for filtering as the sidebands of the image are symmetrical to each other. Inverse Fourier Transform is applied at specific zones to filter the output images. As only one sideband is used for image recovering, therefore this method is effective for teleconferencing in rural medical system using optimum bandwidth. We have used chosen ciphertext attack to prove the effectiveness of our method and we have proved that our system is secure.

Combined in-situ neutron diffraction measurements during post-processing heat treatment and thermo-mechanical crystal plasticity finite element (CPFE) simulations were utilized to study the residual phase stress development in the two-phase microstructure of an additively manufactured (AM) 304L stainless steel. The steel, fabricated via the laser engineering net shaping technique, has a microstructure comprising primarily of the austenite phase, with ∼ 2.5% ferrite phase by volume fraction. The post-build material was heated to greater than 1300 K and neutron diffraction data was recorded during heating and cooling. Specifically, the evolution of lattice strains in the individual phases were measured with temperature and the corresponding coefficients of thermal expansion (CTEs) calculated. The dislocation densities, phase fractions and textures, before and after heat treatment, were also measured. CPFE simulations were performed to study the interplay of the stress-free thermal strains and the mechanical strains in inducing inter-granular residual stresses in individual phases. The simulations confirmed the presence of process induced inter-granular residual stress primarily in the ferrite phase of the as-built AM material. Comparison of the relevant simulation data with experiments indicate that model predictions of the lattice strains and CTEs in both phases, as well as the inter-granular residual phase stress and pressure in the ferrite phase are in qualitative agreement with the experimental measurements and calculations.

Fully recrystallized hexagonal Zirconium was subjected to controlled hot compression tests. Deformation above 723 K showed both flow saturation, characteristic of dynamic recovery, and also the presence of fine equiaxed grains, indicating dynamic recrystallization (DRx). Though data from relative work hardening were inconclusive, a combination of transmission Kikuchi diffraction plus transmission electron microscopy clearly confirmed the presence of DRx grains. A separation between the deformed and the DRx grains was not possible with microtexture or nano-indentation data. Local internal friction measurements (or tanδ values), however, clearly distinguished the DRx grains from both statically recrystallized (SRex) and the hot deformed grains.

High-resolution images are essential in many remote sensing applications such as weather prediction, deforestation, crop monitoring, land mapping, urban growth, etc. In these applications, it is necessary to use multiple high-resolution images for proper analysis. These images carry a lot of information; therefore, multiplexing plays an important role for efficient storage of the images. Hence, we provide an idea of multiplexing high-resolution images using amplitude grating. Initially, images are modulated with variable spatial frequencies and orientation angles followed by the addition of modulated spectrums to form a single spectrum plane. The resultant spectrum plane is filtered before transmission to eliminate noise. To optimize storage space, only a part of the filtered spectrum is transmitted. A pixel intensity graph is plotted to identify the location of maximum information of the images, which is required during the retrieval process. The quality of the output images is analyzed by peak signal-to-noise ratio, structural similarity index measurement, and correlation coefficient methods. The entire work is done by simulation software, and we prove that our proposed multiplexing method is suitable for efficient storage of high-resolution images in remote sensing applications.

This chapter presents a novel method for compressing satellite imagery using phase grating to facilitate the optimization of storage space and bandwidth in satellite communication. In this research work, each Satellite image is first modulated with high grating frequency in a fixed orientation. Due to this modulation, three spots (spectrum) have been generated. From these three spots, by applying Inverse Fourier Transform in any one band, we can recover the image. Out of these three spots, one is center spectrum spot and other spots represent two sidebands. Care should be taken during the spot selection is to avoid aliasing effect. At the receiving end, to recover image we use only one spectrum. We have proved that size of the extracted image is less than the original image. In this way, compression of satellite image has been performed. To measure quality of the output images, PSNR value has been calculated and compared this value with previous techniques. As high-resolution satellite image contains a lot of information, therefore to get detail information from extracted image, compression ratio should be as minimum as possible.

Encryption of remote sensing images is always required as this type of images carry sensitive data. It is the primary criteria to hide it in case of a country’s border image or video. Nowadays development in networking improves communication systems. Unfortunately, intruders are misusing this advantage and try to intrude into the network whose security is weak. During secure communication of remote sensing images, encryption is done before sending to a long distance. Here, we have discussed a new method of remote sensing image encoding with the help of hamming code. During analyzation, we have showed that it is not easy to decode the main image from encrypted data in the most popular mode of attacking- known plaintext attack. Moreover, we have also calculated that this system can detect the error in an effective way. The presented method is also applicable for effective encryption of more than one remote sensing images.

A Crystal Plasticity Finite Element (CPFE) framework is proposed for modeling the non-Schmid yield behavior of L12 type Ni3Al crystals and Ni-based superalloys. This framework relies on the estimation of the non-Schmid model parameters directly from the orientation- and temperature-dependent experimental yield stress data. The inelastic deformation model for Ni3Al crystals is extended to the precipitate phase of Ni-based superalloys in a homogenized dislocation density based crystal plasticity framework. The framework is used to simulate the orientation- and temperature-dependent yield of Ni3Al crystals and single crystal Ni-based superalloy, CMSX-4, in the temperature range 260-1304 K. Model predictions of the yield stress are in general agreement with experiments. Model predictions are also made regarding the tension-compression asymmetry and the dominant slip mechanism at yield over the standard stereographic triangle at various temperatures for both these materials. These predictions provide valuable insights regarding the underlying (orientation- and temperature-dependent) slip mechanisms at yield. In this regard, the non-Schmid model may also serve as a standalone analytical model for predicting the yield stress, the tension-compression asymmetry and the underlying slip mechanism at yield as a function of orientation and temperature., Pre-print submitted to arXiv.org, accepted for publication in Modelling and Simulation in Materials Science and Engineering

Introduction: Lymphedema is a symptom of morphologically or functionally insufficient lymph transport. There are several etiological factors damaging the lymphatic pathways. Infections and trauma of limb skin and deep tissues evoke reaction of peripheral lymphatics and lymph nodes [1]. Aim and Objective: To compare the “efficacy of pneumatic compression therapy (PCT), lymphatic drainage exercises and control group in patient with lower limb lymph edema. Methodology: Subject randomly assigned into three groups viz group A, B and C. Group A patients given Pneumatic Compression Therapy (PCT) and Manual Lymphatic Drainage (MLD). Group B given Lymphatic Drainage Exercises (LDE) and Manual lymphatic drainage (MLD) and Group C given Manual lymphatic drainage (MLD) for lower limb lymph edema. All three groups were treated for four weeks.Results: The age, weight and height of subjects in groups A, B and C were compared by using analysis of variance. There was no significant difference found in age, weight and height in all 3 groups (P>0.05). But significant difference found at 3 to 4 weeks in all 3 groups. (P

A physically based reaction-diffusion model is implemented in the visco-plastic self-consistent (VPSC) crystal plasticity framework to simulate irradiation growth in hcp Zr and its alloys. The reaction-diffusion model accounts for the defects produced by the cascade of displaced atoms, their diffusion to lattice sinks and the contribution to crystallographic strain at the level of single crystals. The VPSC framework accounts for intergranular interactions and irradiation creep, and calculates the strain in the polycrystalline ensemble. A novel scheme is proposed to model the simultaneous evolution of both, number density and radius, of irradiation-induced dislocation loops directly from experimental data of dislocation density evolution during irradiation. This framework is used to predict the irradiation growth behaviour of cold-worked Zircaloy-2 and trends compared to available experimental data. The role of internal stresses in inducing irradiation creep is discussed. Effects of grain size, tex...

A physically-based crystal plasticity framework for modeling irradiation growth and creep is interfaced with the finite element code ABAQUS to study the contact forces and the gap evolution between the spacer grid and the cladding tube as a function of irradiation in a representative section of a fuel rod assembly. Deformation mechanisms governing the gap opening are identified and correlated to the texture-dependent material response. In the absence of coolant flow-induced vibrations, these simulations predict the contribution of irradiation growth and creep to the gap opening between the cladding tube and the springs and dimples on the spacer grid. The simulated contact forces on the springs and dimples are compared to available experimental and modeling data. Various combinations of external loads are applied on the springs and dimples to simulate fuel rods in the interior and at the periphery of the fuel rod assembly. It is found that loading conditions representative (to a first order approximation) of fuel rods at the periphery show higher gap opening. This is in agreement with in-reactor data, where rod leakages due to the synergistic effects of gap opening and coolant flow-induced vibrations were generally found to occur at the periphery of the fuel rod assembly.

Developments in optical image processing have guided a new era in teleconferencing for medical research work. As medical images carry a great deal of information, image storage using minimal space, as well as image recovery, are important research areas for telemedicine services. In this chapter, a new scheme for storing and recovering multiple medical images using a sinusoidal amplitude grating has been proposed. In this scheme, all medical images are modulated separately using a high value of spatial grating frequency; in addition, the orientation angle of the grating is varied during this process. As a result of modulation, three spectra for each image are generated. All spectrum planes are added together to form a single spectrum plane. The entire spectrum plane is Gaussian filtered to eliminate speckle noise. For proper optimization of limited storage space and bandwidth requirements, we transmit only a part of the entire spectrum plane. An intensity graph was plotted to find the location of maximum image information. In the intensity graph, an inverse Fourier transform is applied around the peaks to retrieve the transmitted images. To maintain the quality of the output, information loss of images should be kept to the minimum possible during processing. To measure the quality of the output images, a conventional PSNR checking method was applied. The frequency of the grating should be high to avoid any aliasing problem. The main objective of this work is to provide efficient storage and quick transmission of medical images.

Compression of images is an important application in the field of satellite image processing as it is suitable for optimization of storage space and sharing over the Internet with optimum bandwidth. In our present communication, a new method for compression of satellite images using Butterworth low-pass filtering has been proposed. Initially, we have transformed the selected satellite image into frequency domain. By varying the cutoff frequency, satellite image has been filtered out. We have used three different cutoff frequencies to extract image from its spectrum. However, to get a reasonably good output, information loss of images should be minimized during compression. To measure the quality of the output images, PSNR values have been calculated in each case.

A reliable and accurate glacial monitoring system is being developed with the help of a UAV and high-resolution camera on board. GPS is another major part of system which will help to collect information on glacier melting using reflectrometry principle and complement the information of aerial view of the lake formed due to glacier melting. The information gathered in that way helps the existing human habitat in the vicinity of the glacial lake from Glacial lake Outburst Flood (GLOF), a serious event of North East Indian Himalayan region. The information gathered in that way and generated warning signal are then transmitted to android application which exploits the data for the real time monitoring of the glacier melting as well as increase of area of the lake formed due to glacier melting.

During this Covid - 19 pandemic situation, encryption of medical images takes a major role in medical information systems as well as in telemedicine. However according to government rule, it is essential to hide the information of the patients. Recent development in computer network enhances a lot of facilities in communication area. Unfortunately, hackers are misusing this facility and always try to attack on the transmitted information in insecure network. For secure transmission of medical images, it is essential to encrypt the information before transmitting. In this communication, we are going to present a novel approach of medical image encryption using cyclic coding. We have proved that it is quite difficult to decrypt the original information from encoded data in one common mode of attacking-chosen ciphertext attack. Moreover, we have proved the effectiveness of the encryption using correlation coefficients. Our proposed scheme is suitable for efficient encoding of multiple medical images.

This study explores the effect of crystallographic orientations on the development of residual strains and local misorientations in a polycrystalline Zircaloy-4 during controlled tensile deformation. A combination of experiments (electron backscattered diffraction (EBSD), micro-Laue diffraction) and modeling (crystal plasticity finite element (CPFE)) are used. Data from two sets of grain orientations are analyzed and modeled: orientations within 5° of the exact (0002) basal pole (‘near basal’) and those within 5° of the exact ( 10 1 ‾ 0 ) prism pole (‘near prism’). In order to maintain similitude with experiments, the actual experimental microstructures (along with their crystallographic orientations) are used as an input for the CPFE simulations. Minor differences are observed for different measures of local misorientation developments. However, the ‘near basal’ grains show higher spread of grain reference orientation deviation, both in experiments and in CPFE simulations, and correlate with the intergranular strain heterogeneity predicted from CPFE simulations. Simulated trends of residual strains also compare favorably with the micro-Laue measurements. The ‘near basal’ grains have higher residual strains as compared to the ‘near prism’ grains. This observed behavior appears to originate from the elastic anisotropy of the hcp crystals and not from differences in the plastic deformation on the different family of slip systems.

Development of computer network creates many benefits in digital imaging area which is applicable in satellite imaging too. But this easy access provides virtually unprecedented opportunities to pirate copyrighted satellite images. Maintaining privacy and authenticity in satellite information is an essential requirement but unfortunately it is not possible to do this. It is sometime necessary to identify the copyright information of satellite images. In this case, digital watermarking may be a better tool for this identification. To form digital watermarking, we have to incorporate a special bit pattern into the main information which is useful to identify proper users. In the proposed scheme, a novel method of watermarking application using alpha blending has been discussed. For our research work, we have selected color satellite image which are watermarked with variable values of alpha. Before watermarking, we have filtered the satellite image as well as the cover image using Gauss filtering. As a result of filtering, noise has been eliminated from both the images. The pixel modification has been performed during processing with alpha blending on red, green and blue planes respectively. Using proper value of alpha, original satellite image can be retrieved from the digital watermarked image. We have used conventional quality checking method, PSNR, to analyze the quality of the retrieved image. Applying some post-processing work, this can be used in steganography process of satellite image.

Recent developments in the areas of image processing have guided a new paradigm for research work in communication of images over the internet. Hence, secure storage and retrieval of digital images is a demanding task for future communication services. A scheme to securely store and encrypt multiple images using sinusoidal phase grating is highlighted. In the proposed scheme, images are modulated using different spatial frequencies and orientation angles. In addition, images have been encrypted using random phase mask after filtering. In order to avoid any human intervention in the system, an intensity graph is plotted to retrieve the images by applying inverse Fourier transform. Using this method, it is possible to independently store, encrypt, and retrieve multiple images due to absence of aliasing problem.

We propose a multi-scale modeling approach that can simulate the microstructural and mechanical behavior of metal/alloy parts with complex geometries subjected to multi-axial load path changes. The model is used to understand the biaxial load path change behavior of 316L stainless steel cruciform samples. At the macroscale, a finite element approach is used to simulate the cruciform geometry and numerically predict the gauge stresses, which are difficult to obtain analytically. At each material point in the finite element mesh, the anisotropic viscoplastic self-consistent model is used to simulate the role of texture evolution on the mechanical response. At the single crystal level, a dislocation density based hardening law that appropriately captures the role of multi-axial load path changes on slip activity is used. The combined approach is experimentally validated using cruciform samples subjected to uniaxial load and unload followed by different biaxial reloads in the angular range [ 27 ° , 90 ° ] . Polycrystalline yield surfaces before and after load path changes are generated using the full-field elasto-viscoplastic fast Fourier transform model to study the influence of the deformation history and reloading direction on the mechanical response, including the Bauschinger effect, of these cruciform samples. Results reveal that the Bauschinger effect is strongly dependent on the first loading direction and strain, intergranular and macroscopic residual stresses after first load, and the reloading angle. The microstructural origins of the mechanical response are discussed.

Development of computer networking generates many benefits in cyber world. Due to this great advancement, nowadays networking facilities are available at very low cost. But unfortunately this easy access becomes a threat to information security. Watermarking is a technique that is very often used in image processing to trace copyrighted products. It can also be used to trace products which are illegally distributed without permission. In our research work, a new technique for invisible watermarking of images using alpha blending has been proposed. Alpha blending is used to display an alpha bitmap and an alpha bitmap is that one which has transparent and semi-transparent pixels. We have worked on color image and gray scale image. Gray scale image is used as watermark image which is kept hidden in the main scale image by different values of alpha in alpha blending method. This technique is actually done on each plane of the color image. The resulting image contains the information of color image and gray scale images but the main image is unseen to others. PSNR values are also calculated to check the robustness of the reconstructed image. Applying some post-processing work, this can be used in image steganography also.

A computational framework is developed to study the role of microstructure on the deformation behavior of Mo–Si–B alloys. A parametric range of idealized multi-phase microstructures of Mo–Si–B alloys are instantiated in 2D using Voronoi tessellation schemes and their deformation behavior modeled with the use of the finite element method. Continuum elements are used to model the constituent phases, while cohesive elements are used to model debonding at the interfaces of the intermetallic (A15 and T2) phases with the solid solution-strengthened Moss matrix and cleavage fracture within the intermetallic phases. The deformation behavior of Mo–Si–B alloys is studied in terms of the simulated stress-strain response and microstructure evolution characteristics. Effects of various microstructure parameters, such as composition and clustering of intermetallic phases, on the tensile strength and ductility are also studied.

A continuum damage framework is developed and coupled with an existing crystal plasticity framework, to model failure initiation in irradiated bcc polycrystalline materials at intermediate temperatures. Constitutive equations for vacancy generation due to inelastic deformation, void nucleation due to vacancy condensation, and diffusion-assisted void growth are developed. The framework is used to simulate failure initiation at dislocation channel interfaces and grain boundaries ahead of a sharp notch. Evolution of the microstructure is considered in terms of the evolution of inelastic deformation, vacancy concentration, and void number density and radius. Evolution of the damage, i.e., volume fraction of the voids, is studied as a function of applied deformation. Effects of strain rate and temperature on failure initiation are also studied. The framework is used to compute the fracture toughness of irradiated specimens for various loading histories and notch geometries. Crack growth resistance of the irradiated specimens are computed and compared to that of virgin specimens. Results are compared to available experimental data.

In this work, a physics-based thermal creep model is developed based on the understanding of the microstructure in Fe-Cr alloys. This model is associated with a transition state theory-based framework that considers the distribution of internal stresses at sub-material point level. The thermally activated dislocation glide and climb mechanisms are coupled in the obstacle-bypass processes for both dislocation and precipitate-type barriers. A kinetic law is proposed to track the dislocation densities evolution in the subgrain interior and in the cell wall. The predicted results show that this model, embedded in the visco-plastic self-consistent framework, captures well the creep behaviors for primary and steady-state stages under various loading conditions. The roles of the mechanisms involved are also discussed.

Constitutive equations are developed for single crystal bcc-Fe at low and ambient temperatures based on the assumption that non-Schmid effects are primarily influential on orientation dependence and tension–compression asymmetry of the initial yield stress. Temperature dependence of the non-Schmid parameters is extracted from a fit to available experimental data. Constitutive models are also developed for the decay of the influence of non-Schmid stresses with inelastic deformation. These equations are used in a dislocation density-based crystal plasticity framework to model the mechanical behavior of bcc-Fe. The stress–strain response is modeled and fit to the experimental data at 298 K. Orientation-dependent yield stress and tension–compression asymmetry simulations are compared to available experiments.

A continuum constitutive crystal plasticity framework is implemented to model the post-irradiation tensile behavior of bcc structural materials, accounting for localized deformation due to the formation of dislocation channels. Both the mechanical response and deformed microstructure of the material are modeled for quasi-static tensile loading. The latter is studied to identify the stages of dislocation channel formation during localization, specifically with respect to the evolution of dislocations and irradiation-induced defects. Parametric studies of the cross-slip and flow softening (due to annihilation of irradiation-induced defects) models are performed to study their effects on the localization behavior. Results are compared to available experimental data.

This report describes the implementation of a crystal plasticity framework (VPSC) for irradiation hardening and plastic deformation in the finite element code, MOOSE. Constitutive models for irradiation hardening and the crystal plasticity framework are described in a previous report [1]. Here we describe these models briefly and then describe an algorithm for interfacing VPSC with finite elements. Example applications of tensile deformation of a dog bone specimen and a 3D pre-irradiated bar specimen performed using MOOSE are demonstrated.

This Milestone report shows good progress in interfacing VPSC with the FE codes ABAQUS and MOOSE, to perform component-level simulations of irradiation-induced deformation in Zirconium alloys. In this preliminary application, we have performed an irradiation growth simulation in the quarter geometry of a cladding tube. We have benchmarked VPSC-ABAQUS and VPSC-MOOSE predictions with VPSC-SA predictions to verify the accuracy of the VPSCFE interface. Predictions from the FE simulations are in general agreement with VPSC-SA simulations and also with experimental trends.

It is essential to understand the deformation behavior of these Fe-Cr-Al alloys, in order to be able to develop models for predicting their mechanical response under varied loading conditions. Interaction of dislocations with the radiation-induced defects governs the crystallographic deformation mechanisms. A crystal plasticity framework is employed to model these mechanisms in Fe-Cr-Al alloys. This work builds on a previously developed defect density-based crystal plasticity model for bcc metals and alloys, with necessary modifications made to account for the defect substructure observed in Fe-Cr-Al alloys. The model is implemented in a Visco-Plastic Self Consistent (VPSC) framework, to predict the mechanical behavior under quasi-static loading.

A constitutive crystal plasticity model is proposed and developed for the inelastic deformation of irradiated bcc ferritic/martensitic steels. Defects found in these irradiated materials are used as substructure variables in the model. Insights from lower length- and time-scale simulations are used to frame the kinematic and substructure evolution relations of the governing deformation mechanisms. Models for evolution of mobile and immobile dislocations, as well as interstitial loops (formed due to irradiation), are developed. A rate theory-based approach is used to model the evolution of point defects generated during irradiation. The model is used to simulate the quasi-static tensile and creep response of a martensitic steel over a range of loading histories.

This article considers the issue of designing a nonlinear control strategy for a batch reactive rectifier. The hybrid control strategy consists of a state estimator, namely Luenberger-like nonlinear estimator (LNE) and the feedback linearizing controller (FLC). The LNE observation scheme aims to estimate the imprecisely known parameter (augmented state) along with the unmeasured state using the available state information. The state predictor includes only two ordinary differential equations and is formulated based on the component continuity equation around the condenser-reflux drum envelope. It implies that the predictor model is not a perfect representation of the actual process. For effective handling of this structural discrepancy, the corrector model is coupled with the predictor in the LNE estimator. The next part of this article synthesizes the FLC controller for the example system. A comparison is made in terms of closed-loop performance between the FLC-LNE scheme and gain-scheduled proportional integral (GSPI) controller. Extensive simulation results reveal that the proposed structure appears to be a promising approach to the control of the batch distillation column.