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This work examines the effects of varying weight percentages (0.1, 0.3, and 0.5 wt%) of pristine and functionalized graphene (–COOH, –OH, and –NH2) on the compression and impact strength of carbon fiber-reinforced polymer (CFRP) composite laminates. The laminates were fabricated in two different stacking sequences of carbon fiber in composite laminates, i.e., 0/90° and 0/90/ ± 45° by hand layup technique. Experimental results showed that the inclusion of graphene in epoxy matrix enhances the compressive strength and impact characteristics, namely impact force, displacement, energy profile, and damage behavior of CFRP laminates. Moreover, the orientation of carbon fiber layers in laminates affects the internal damage behavior of specimens and the delamination between fiber layers. The maximum improvements of 38.65 and 76.82% are noticed in the compressive strengths of 0/90° and 0/90/ ± 45° stacked laminates with the reinforcement of 0.1 wt% of pristine and 0.3 wt% of –COOH functionalized graphene to epoxy, respectively. In summary, the test results have shown that using graphene as a reinforcing filler can significantly improve the impact performance of CFRP composites. [ABSTRACT FROM AUTHOR]

Zeolites, with their well‐defined pore sizes and outstanding stability, are regarded as the quintessential material for precise molecular separation tasks. However, the leap from easily produced zeolite powders to synthesizing free‐standing zeolite membranes, which can fully leverage their ordered porosity, presents substantial technical hurdles. Addressing this challenge, this study introduces polymers of intrinsic microporosity (PIM‐1) as adhesives through a wrapping‐compression method for the facile fabrication of high‐performance and free‐standing zeolite (FAU) “particle board” membranes. The 3D tomogram reconstruction from the focused ion beam‐scanning electron microscope images reveals the “particle board” membranes exhibit hierarchical porous structures. The non‐interconnecting macropores between zeolite particles facilitate the rapid H2 permeation, and the zeolites’ ordered micropores sieve the gas molecules. The optimized FAU@PIM‐1 free‐standing membrane with hierarchically pore structures demonstrated hydrogen permeance (2240 GPU) alongside H2/CH4 selectivity (31.68) for mixed gas and maintained this performance level under pressure ranges from 1.2 to 4.0 bar and over protracted operational periods (up to 3200 h). Meanwhile, EMT and MFI‐type zeolites have also been successfully applied to validate the versatility of this method, demonstrating its widespread potential for the fabrication of various free‐standing zeolite membranes. [ABSTRACT FROM AUTHOR]

Weft-knitted spacer fabrics are thick 3D knitted structures prized for their cushioning properties which have gathered increasing attention in the last decade. The thickness of a spacer fabric is one of its most influential parameters and strongly impacts its cushioning properties, wearability, thermal insulation or permeability. However, the fabric's natural undulation and high deformability make its thickness measurement uneasy. The current standard measurement methods require to measure the fabric thickness after compressing it until a fixed threshold stress value is reached to flatten it. The diversity of these threshold values is confusing, and each of them is unsuitable to variety of fabric rigidity. In this article, a standard for thickness evaluation was proposed and used to measure the thickness of 20 samples knitted with 5 independent parameters. The measured thickness was compared to the thickness measured at a threshold value of 1 kPa and to a theoretical thickness. The proposed measurement standard was proved reproducible and efficient for all fabrics when the threshold measures showed large errors on the softer and stiffer samples. The flattening stress of the fabrics ranged from 86 to 5262 Pa and could not be approximated by a single standard value. The theoretical thickness was more accurate, predicting the thickness with an average error of 3.8%. [ABSTRACT FROM AUTHOR]

Lattice structures, characterized by their repetitive, interlocking patterns, provide an efficient balance of strength, flexibility, and reduced weight, making them essential in fields such as aerospace and automotive engineering. These structures use minimal material while effectively distributing stress, providing high resilience, energy absorption, and impact resistance. Composed of unit cells, lattice structures are highly customizable, from simple 2D honeycomb designs to complex 3D TPMS forms, and they adapt well to additive manufacturing, which minimizes material waste and production costs. In compression tests, lattice structures maintain stiffness even when filled with powder, suggesting minimal effect from the filler material. This paper shows the principles of creating finite element simulations with 3D-printed specimens and with usage of the lattice structure. The comparing of simulation and real testing is also shown in this research. The efficiency in material and energy use underscores the ecological and economic benefits of lattice-based designs, positioning them as a sustainable choice across multiple industries. This research analyzes three selected structures—solid material, pure latices structure, and boxed lattice structure with internal powder. The experimental findings reveal that the simulation error is less than 8% compared to the real measurement. This error is caused by the simplified material model, which is considering the isotropic behavior of the used material PA12GB (not the anisotropic model). The used and analyzed production method was multi jet fusion. [ABSTRACT FROM AUTHOR]

Video analytics can achieve increased speed and efficiency by operating directly on the compressed video format, thereby alleviating the decoding burden on the analytics server. The encoded video streams are rich in semantic binary information and this information can be utilized more efficiently to train the classifiers. Motivated by the same notion, a deep learning-based video compression-cum-classification network has been proposed. In the proposed work, the binary-coded semantic information is extracted by using an auto encoder-based video compression component and the same fed to the MobileNetv2-based classifier for the classification of the given video streams based on their content. Using large-scale user-generated content provided by YouTube UGC dataset, it has been demonstrated that using deep neural networks for compression not only provides on-par compression results to traditional methods, it makes analytical processing of these videos faster. Video content tagging of YouTube UGC dataset has been used as the analytics task. The proposed DLVCC approach performs 10 × faster with 30 × fewer parameters than MobileNetv2 in video tagging of compressed video with no loss in accuracy. [ABSTRACT FROM AUTHOR]

From 2012 to 2019, there were approximately 3455 large-scale National Football League injuries reported. There is widespread commercial acceptance of compression garments as tools for reducing injury, promoting recovery, and improving performance in athletic activity. While studies have been conducted to assess the exercise physiology benefits of compression garments, there remains a gap in the scientific literature regarding the clothing comfort and resultant thermoregulation effects of compression girdles for performance athletes. This study aimed to assess the effects of tighter fitting, multi-layer compression systems when worn by American football athletes. A negative impact on thermoregulation may negate or outweigh any realized local benefit such as increased skin blood flow or reduced muscle oscillatory properties. Therefore, the purpose of this research was to determine the predicted hypothalamus temperature, skin blood flow, skin temperature, sweat rate, temperature sensation, and comfort perceptions of the male human body when wearing a compression girdle. A sweating thermal manikin was utilized to predict the physiological responses of a 50th percentile male when wearing football girdles in both practice and play settings. The results indicate significant differences in skin blood flow, skin temperature, core temperature, sweat rate, and comfort and sensation perceptions when wearing compression girdles compared to boxer briefs in replicated practice and play settings. Findings also demonstrate the use of real-time manikin simulation modeling for predicting physiological response outcomes of wearing compression garments to a realized extent. [ABSTRACT FROM AUTHOR]

Recently, cellular materials made by the repetition of unit cells, that is, iron lattices have become appealing to mimic the structure of bone. The aim of the study is to choose the most adequate lattice structures, which have the compressive mechanical properties closer to the ones of bone, in the perspective of their use as temporary implants. Five types of unit cells were selected, such as, cubic (C), truncated octahedron (TO), truncated cubic (TC), rhombicuboctahedron (RCO), and rhombitrucated cuboctahedron (RTCO). The mechanical properties were assessed by numerical simulations with a finite-element analysis. The size effect was studied with the comparison of results among samples with different numbers of unit cells. Simulations covered a wide range of relative densities. Graded dense-in and dense-out configurations were constructed with lattices of types RTCO and TO, being the unit cells, themselves graded. Lattice structures RTCO and TO were found to be stable at every relative density studied, while C, TC and RCO lattices are unstable at low densities. The evaluation of size effects was not conclusive, which could be biased by other factors. The Young's modulus of RTCO and TO lattices enable to reproduce the properties of both trabecular and cortical bone, with an appropriate choice of the relative density. To mimic trabecular bone, only RTCO and TO structures with low relative densities, can be used, while arrangements of C, TC and RCO cells can only replicate the properties of cortical bone. Graded cells may have the same properties as non-graded with lower density. [ABSTRACT FROM AUTHOR]

Delta encoding is a data reduction technique capable of calculating the differences (i.e., delta) among very similar files and chunks. It is widely used for various applications, such as synchronization replication, backup/archival storage, cache compression, and so on. However, delta encoding is computationally costly due to its time-consuming word-matching operations for delta calculation. Existing delta encoding approaches either run at a slow encoding speed, such as Xdelta and Zdelta, or at a low compression ratio, such as Ddelta and Edelta. In this article, we propose Gdelta, a fast delta encoding approach with a high compression ratio. The key idea behind Gdelta is the combined use of five techniques: (1) employing an improved Gear-based rolling hash to replace Adler32 hash for fast scanning overlapping words of similar chunks, (2) adopting a quick array-based indexing for word-matching, (3) applying a sampling indexing scheme to reduce the cost of traditional building full indexes for base chunks' words, (4) skipping unmatched words to accelerate delta encoding through non-redundant areas, and (5) last but not least, after word-matching, further batch compressing the remainder to improve the compression ratio. Our evaluation results driven by seven real-world datasets suggest that Gdelta achieves encoding/decoding speedups of 3.5X∼25X over the classic Xdelta and Zdelta approaches while increasing the compression ratio by about 10%∼240%. [ABSTRACT FROM AUTHOR]

This paper introduces a new protocol named MEDCO for eMErgency Detection and COmpression, designed to minimize data transmission and optimize sensor energy usage in wireless body sensor networks. MEDCO operates in two stages. The first stage assesses the patient's condition based on vital signs and compares it with the previous state to determine if the data should be transmitted to medical staff. Data is only sent if a change in the patient's situation is detected. The second stage focuses on compressing the identified data using two algorithms: range and changed vital signs methods. The range method classifies patient readings into ranges based on the current health situation before compressing them. At the same time, the changed vital signs algorithm considers both current and previous situations during compression. Through simulations using actual patient data, we demonstrated the effectiveness of our protocol in reducing data transmission by 97% while maintaining a high level of accuracy in the transmitted information. The range method outperforms by achieving an additional data reduction of 34.6% compared to the selected protocol from state of the art, and the changed vital signs method achieves a reduction of 6.4%. [ABSTRACT FROM AUTHOR]

Objectives: Our objective was to assess morbidity trends in Europe and to classify European countries based on population ageing theories: the compression, expansion and dynamic equilibrium of morbidity. Methods: The proportions of healthy life years were calculated for 31 European countries for the period 2005--2019 based on life expectancy values and healthy life years at age 65 years adopted from the Eurostat database. European countries were classified according to morbidity patterns applying the standard deviation distance from the average of relative change method between the selected years. Results: A large degree of variation in terms of life expectancy and healthy life years at age 65 years was determined between 2005 and 2019. While the life expectancy differences between men and women were consistent across all the European countries, the gender gap concerning healthy life years was more diverse. Approximately one-third of the countries fell into the expansion, compression and dynamic equilibrium categories, respectively. Conclusion: Significant variations were identified in healthy life year trends across European countries, which underscores the need for preventive strategies. [ABSTRACT FROM AUTHOR]

ABSTRACT The detection of brain tumours presents a significant challenge in the medical domain, where prompt and precise diagnosis is crucial as patient outcomes depend on it. Conventional deep neural networks perform well in carrying out various imaging tasks within the healthcare sector; however, their effectiveness often falls short of expectations in practical applications due to the substantial computational resources required and issues with reliability. In this research, an optimised and effective deep learning model founded on the DenseNet‐169 architecture is introduced for the classification of magnetic resonance imaging brain tumours, which is particularly advantageous for smart healthcare systems and information and communication technology (ICT) settings with limited computational capabilities. The model compression methodologies, including pruning and quantization, have been employed to significantly diminish the dimensions and intricacy of the model while achieving a classification accuracy of 97.07%. Furthermore, this endeavour necessitates the enhancement of the model's interpretability through the utilisation of explainable artificial intelligence methodologies such as Gradient‐weighted Class Activation Mapping (Grad‐CAM) and SHapley Additive exPlanations (SHAP), which will aid clinicians in highlighting crucial areas of the images and validating feature importance concerning the decisions rendered by the model. A comparative performance evaluation is conducted against DenseNet‐169, ResNet‐50 and various other models to delineate the superior efficacy of our model, rendering it exceptionally adept for knowledge‐driven, real‐time brain tumour diagnosis within smart healthcare and ICT systems where resources are constrained. [ABSTRACT FROM AUTHOR]

This experimental work involves characterization and fractography of a bio‐based epoxy and an in‐situ polymerisable thermoplastic polymer matrix based non‐crimp glass and carbon fiber composites under compressive loading. The laminates are characterized under compression loading using a combined loading compression (CLC) fixture. Laminates made using the thermoplastic matrix exhibit higher compressive strength (approx. 20% along fiber direction) compared to the bio‐epoxy based laminates. Further, both composites exhibit comparable compressive modulus characteristics. The tested composites are subjected to fractography analysis using Scanning Electron Microscopy (SEM) and Computed tomography (CT). SEM results indicate a difference in fiber‐matrix interface characteristics between the thermoplastic matrix and the bio‐epoxy matrix. Additionally, the CT scans reveal a difference in failure modes due to fiber orientations. A difference between failure mode of the exterior and interior plies of the specimens was also noticed. However, no specific influence of matrix type was observed on the overall macroscopic failure behavior. Highlights: Bio‐epoxy and thermoplastic based laminates were characterized in compression.Post‐test fractography was performed using SEM and x‐ray CT scans.Use of thermoplastic matrix exhibits better fiber‐matrix adhesion compared to bio‐epoxy.Both laminates performed well in compression under laboratory test conditions. [ABSTRACT FROM AUTHOR]

Adductor canal (Hunter’s canal) pathologies are often underdiagnosed, with the saphenous nerve being the most commonly affected. While uncommon, involvement of the femoral artery and vein can cause severe and irreversible complications if not detected early. Significant attention must be given to adductor canal pathologies because the musculoaponeurotic tunnel is predominantly fibrotic with minimal adipose tissue. As a result, any edema or space-occupying lesion can lead to early compression of the structures within the adductor canal. Incorporating adductor canal syndrome into the imaging differential diagnosis is essential. For diagnosing and sometimes managing these conditions. In this article, we describe the anatomy and spectrum of pathologies involving the Hunter’s canal. [ABSTRACT FROM AUTHOR]

Background: Chromosome organization plays an important role in biological processes such as replication, regulation, and transcription. One way to study the relationship between chromosome structure and its biological functions is through Hi-C studies, a genome-wide method for capturing chromosome conformation. Such studies generate vast amounts of data. The problem is exacerbated by the fact that chromosome organization is dynamic, requiring snapshots at different points in time, further increasing the amount of data to be stored. We present a novel approach called the High-Efficiency Contact Matrix Compressor (HiCMC) for efficient compression of Hi-C data. Results: By modeling the underlying structures found in the contact matrix, such as compartments and domains, HiCMC outperforms the state-of-the-art method CMC by approximately 8% and the other state-of-the-art methods cooler, LZMA, and bzip2 by over 50% across multiple cell lines and contact matrix resolutions. In addition, HiCMC integrates domain-specific information into the compressed bitstreams that it generates, and this information can be used to speed up downstream analyses. Conclusion: HiCMC is a novel compression approach that utilizes intrinsic properties of contact matrix, such as compartments and domains. It allows for a better compression in comparison to the state-of-the-art methods. HiCMC is available at https://github.com/sXperfect/hicmc. [ABSTRACT FROM AUTHOR]

The functional signal of bone internal structure has been widely studied. Isolated form‐function relationships have often been assumed from the observation of presumed morphofunctional relationships, but have never been truly tested. Indeed, distinct bone microanatomical feature co‐evolve in response to various constraints that are difficult to detangle. This study tested for the first time the impact of various microanatomical parameters taken one by one, plus some in pairs, on bone strength under compression using biomechanical modelling. We carried out finite element analyses on humerus models, obtained from a white rhinoceros, with different heterogeneous internal structures, and analysed the magnitude and distribution of von Mises stresses. These tests validated earlier hypotheses of form‐function relationships about the greater resistance to compression provided by the thickening of the cortex and the filling of the medullary area by trabecular bone and highlighted the stronger impact of increasing trabecular bone compactness than of avoiding an open medullary cavity. By making it possible to estimate the relative impact of each parameter and of combinations of microanatomical features, they also showed the more limited impact of the trabecular bone compactness in the epiphyses to resist compression, and the fact that microanatomical changes of opposite but of similar amplitude impact can compensate each other, but that the impact of the sum of two negative microanatomical changes far exceeds the sum of the impacts of each of the two changes taken separately. These results contribute to a better understanding of bone adaptation and form‐function relationships so that they later can be used with confidence for palaeobiological inferences on fossil specimens, contributing to a better understanding of skeletal evolution during the evolutionary history of vertebrates. They also highlight the potential of taking internal structure into account in the bone biomechanical analyses. In addition, they can be used in bioinspiration to design resistant structures subjected to compression. [ABSTRACT FROM AUTHOR]

Background: Hydatid disease is a zoonotic infection caused by the species Echinococcus that typically affects the liver. Most liver hydatid cysts are asymptomatic at first, but as the cyst grows larger, symptoms, such as compression effects, start to appear. Ultrasonography and computed tomography scans are the widely used diagnostic tools, and surgery is considered the mainstay of treatment. Case presentation: We present an unusual case of a giant pedunculated hydatid cyst causing inferior vena cava syndrome in a 20-year-old male patient from the Oromo ethnic group from a rural area of the country. Abdominal ultrasound and computed tomography scan confirmed the diagnosis. Our patient underwent radical surgical resection of the cyst and had a good outcome. Conclusion: Hydatid liver cyst diagnosis needs a high index of suspicion for echinococcal etiology when dealing with a giant liver cyst as it results in grave complications without any manifestations. [ABSTRACT FROM AUTHOR]

Compression of compressible, linearly elastic, annular disks by flat rigid platens is analyzed. Coulomb (Amonton) friction is assumed to act at the interfaces between the disk and the platens. Slip may occur in an outer annular region while the inner annular (bonded, stick) region of the disk does not slip. The critical radius (slip boundary) is of major interest. The governing equilibrium equations in terms of the deflections are satisfied exactly. Approximations are made in some of the boundary conditions and the transition (matching) conditions at the critical radius. Numerical results are presented for nearly incompressible disks. The effects of the radius ratio, aspect ratio, and Poisson's ratio of the disk, and of the coefficient of friction at the platens, on the critical radius, effective compression modulus, stresses, and radial deflection are investigated. Applications include structural (especially bridge) bearings, seismic-isolation devices, mounting blocks and bushings, gaskets, and sealing components. [ABSTRACT FROM AUTHOR]

Some patients develop breast/chest lymphoedema following breast cancer treatment. Historically this group of patients has been managed in the same way as those with limb lymphoedema, through the application of compression in the form of vests or bras. Some patients reported pain and the feeling of being in a 'strait jacket' and, therefore, abandoned these items for lighter and more comfortable garments without any adverse effects. Reflecting on this insight, the author adapted breast/chest lymphoedema management by suggesting a change to lighter garments to patients who reported improved comfort, with no obvious negative impact on their lymphoedema. Within this article, the author gives a brief explanation of lymphatic mechanisms and factors relating to lymphoedema including signs and symptoms of breast oedema. There will be an exploration of the available treatments for lymphoedema along with treatment plans found to be effective by the author. [ABSTRACT FROM AUTHOR]

Background and Purpose: Developing technology in the field of rehabilitation is vital to accelerate recovery and decrease the side effects of current modalities. Rehabilitation is a challenging science in which the main challenge is not just treating the patient but also to shorten the rehabilitation time and avoid harmful effects. Thus, this review demonstrates the possible design and effects of air therapy as a novel treatment branch besides hydrotherapy, electrotherapy, and manual therapy in the field of rehabilitation. Methods: The search was conducted over clinical trials, literature reviews, and systematic reviews on the possible effects of treatments that may have similar effects to the newly developed air therapy. This search was conducted in the Web of Science, Scopus, EBSCO, and Medline databases. Results: Air therapy could be used to improve the function of mechanoreceptors, improve circulation and microcirculation, decrease pain, the release of trigger points, regain the elasticity of soft tissues, treat acute and chronic inflammations, decrease muscle cramps and spasticity, strengthen muscle, and decrease muscle fatigue and Decreasing muscle fatigue and delayed muscle soreness. Conclusion: Air therapy is a novel treatment modality that can be used effectively in the field of rehabilitation. Air therapy could be a valuable and safe treatment in rehabilitation. [ABSTRACT FROM AUTHOR]

The advent of 3D printing has revolutionized the manufacturing landscape, enabling the creation of intricate structures and personalized designs. The use of multi-material polymer composites in additive manufacturing has further expanded possibilities, offering enhanced mechanical properties and advanced functionalities. In the present study, PLA/Almond shell reinforced PLA (PLA/AmdPLA) multi-material composites were developed using Fused Filament Fabrication (FFF) method. The objective of this study is to develop the multi-material and optimize the 3D-Printing Parameters (3D-PP) with respect to Printing Speed (PS), Layer Height (LH), and Printing Temperature (PT), in order to maximize the compressive strength of the composites. The L16 Taguchi orthogonal array was established to systematically study the effects of the 3D-PP on the compressive strength. Through a series of experiments, varying the levels of each 3D-PP, data was collected and analyzed to determine the optimal 3D-PP settings. The results demonstrate that the PLA/AmdPLA multi-material composites achieved its maximum compressive strength when fabricated at a PS of 20 mm/sec, a LH of 0.1 mm, and a PT of 210°C. Furthermore, the findings revealed that the PS and LH significantly influenced the compressive strength, while the PT exhibited moderate effects. The regression analysis results indicate that the compression experiments conducted on the PLA/AmdPLA multi-material composites yielded an error percentage of 4.73%. This suggests a strong agreement between the predicted values obtained from the regression model and the actual experimental results which shows that the model has high accuracy. Therefore, these functional composite materials are recognized for their superior strength, lightweight properties, appealing aesthetics, and sustainable qualities in various consumer applications. [ABSTRACT FROM AUTHOR]

This article discusses the mechanical evaluation of recycled PETG filament for 3D printing. The authors emphasize the importance of plastic recycling and the potential of 3D printing in manufacturing. They focus on PETG as a leading material for 3D printing and examine the feasibility of recycling PETG for additive manufacturing. The study demonstrates that PETG 3D printing waste can be effectively recycled into new filament with promising mechanical properties. The research aims to contribute to the understanding of sustainable usage of PETG in 3D printing and inform future efforts in optimizing recycling processes. Another document provides information on the mechanical properties and testing of a specific material used in 3D printing. The material is tested in two different forms, filament and pellets, to compare their characteristics. The testing includes tensile, compression, and impact tests, with results showing slight differences between the two forms of the material. The document also describes the equipment used for the testing process. Additionally, another document presents the results of a study on the behavior of PETG filament in 3D printing when comparing specimens printed from new material versus recycled material. The study conducted compression, tensile, and impact tests on the specimens. The findings indicate a marginal difference in stiffness, with recycled material exhibiting slightly higher stiffness and increased brittleness. However, caution is advised in drawing definitive conclusions based on this initial data, as the sample size was small and only one recycling cycle was examined. Further research is needed to understand the effects of recycling on material [Extracted from the article]

The dissemination of additive manufacturing methods has facilitated the design and production of complex structures which have a high strength-to-weight ratio. Cellular materials such as honeycombs have low-weight and high capacity to absorb energy which makes them desirable for the aerospace and automotive industries. The present work covers the study and comparison of metal-based regular honeycombs and functionally graded honeycombs. The latter encompass radial and linear/longitudinal gradients. Three repeating unit cells were studied: regular hexagons, Plateau and lotus. The structures were produced in aluminium using the laser powder bed fusion technique. Selected samples were submitted to a stress-relieving heat treatment. Numerical and experimental methods were used to assess the in-plane compressive properties. Finite element analysis was used to obtain the simulated force–displacement curves of each structure, allowing for the calculation of specific stiffness, absorbed energy and yield strength. The experimental method consisted of the compression of three specimens of three types of regular structures with and without stress-relieving heat treatment. The heat treatment reduced the yield strength and stiffness whilst increasing the ductility of the samples. The mechanical behaviour of the structures was found to depend upon a combined effect of the type of gradient, relative density, and unit cell structure. The results showed that an increase in the relative density would enhance the specific mechanical properties. The lotus configuration displayed the highest specific mechanical properties, as its geometry reduces the stress concentrations. The numerical results showed a reasonable match with the experimental results. [ABSTRACT FROM AUTHOR]

Pentamodes are lattice structures composed of beams. Their main property is the low ratio of the shear to bulk modulus, making them suitable for aerospace, antiseismic, and bioengineering applications. At first, in our study, pentamode structures were fabricated using three-dimensional printing and were tested in a laboratory. Then, computational analyses of bulk strength have been performed. In addition, several preliminary computational analyses have been considered, comparing different pentamodes' dimensions and topologies in order to understand their behaviour under different loading conditions. Experimental results have been compared with the numerical results in order to validate the forces applied to the lattice structures. Our new contribution is that for the first time, the experimental and numerical results are investigated up to the failure of the specimens, the effective Young's modulus has been calculated for different pentamode lattice structures, and our results are also compared with analytical equations. [ABSTRACT FROM AUTHOR]

Analysis of ECG for detecting different cardiovascular diseases requires real-time ECG signals which are acquired by attaching electrodes to the body. During the ECG signal acquisition, noise gets added to original signal, which might distort the morphological features, like amplitude, segment length and the interval aspects of the ECG leading to a false diagnosis and improper interpretation of cardiovascular disease. Therefore, ECG denoising is imperative. Here, we propose approximation using hermite polynomial interpolation with chebyshev nodes for denoising electrocardiogram signals that consequently compresses them too. Recommended algorithm is applied on twelve ECG signals taken from MIT-BIH arrhythmia database without any additional noise as the signals are already corrupted with noise. Performance of the proposed algorithm is evaluated using various performance metrics. Experimental results prove that the proposed method efficiently denoises electrocardiogram signals and gives quite encouraging results when compared with other existing denoising and compression algorithms. [ABSTRACT FROM AUTHOR]

In deep learning (DL) frameworks, a checkpoint operation is widely used to store intermediate variable values (e.g., weights, biases, and gradients) on storage media. This operation helps to reduce the recovery time of running a machine learning (ML) model after sudden power failures or random crashes. However, the checkpoint operation can stall the overall training step of the running model and waste expensive hardware resources by leaving the GPU in idle sleep during the checkpoint operation. In addition, the completion time of the checkpoint operation is unpredictable in cloud server environments (e.g., AWS and Azure) because excessive I/O operations issued by other running applications interfere with the checkpoint operations in the storage stacks. To efficiently address the above two problems, we carefully designed Check-QZP, which reduces the amount of data required for checkpoint operations and parallelizes executions on the CPU and GPU by understanding the internal behaviors of the training step. For the evaluation, we implemented Check-QZP and compared it with the traditional approach in real-world multi-tenant scenarios. In the evaluation, Check-QZP outperformed the baseline in all cases in terms of the overall checkpoint time and the amount of data generated by the checkpoint operations, reducing them by up to 87.5% and 99.8%, respectively. In addition, Check-QZP achieved superior training speeds compared to the baseline. [ABSTRACT FROM AUTHOR]

Geopolymers (GPs) are emerging, low‐density ceramic materials that are simple to manufacture, with high elastic modulus and strength, albeit with low toughness. Fiber reinforcements have been used to achieve varied ductile behaviors, but little is known about the GP addition to polymeric frame structures. Thus, drawing inspiration from the nanostructure of bones, this paper investigated an interpenetrating, co‐continuous composite consisting of a GP as the stiff but brittle phase, and a 3D‐printed polymer (PA12 White) as the soft and deformable phase. The composite mechanical properties and failure modes were studied experimentally using uniaxial compression and four‐point bending tests. The co‐continuous network constrained brittle cracking within the GP and reduced strain localization in the polymer. The results showed that the composite had higher strength (56.11 ± 2.12 MPa) and elastic modulus (6.08 ± 1.37 GPa) than the 3D‐printed polymer and had higher toughness (5.98 ± 0.24 MJ/mm3) than the GP for the specific geometries examined. The shape effect study demonstrated that cubic structures had higher elastic modulus and strength but at the expense of lower toughness when compared to rectangular prism structures. The study of scale effects indicated that increasing the number of periodic unit cells while maintaining consistent bulk dimensions led to augmented strength and toughness, albeit without statistically significant alterations in elastic modulus. Thus, this paper presents an experimental realization of a novel, bio‐inspired, interpenetrating, GP–polymer composite design, offering improved strength and toughness. It also provides valuable insights into the shape and size effects on the mechanical properties of this new composite. [ABSTRACT FROM AUTHOR]

This comprehensive review paper delves into the utilization of Glass Fiber-Reinforced Polymer (GFRP) composites within the realm of concrete column reinforcement, spotlighting the surge in structural engineering applications that leverage GFRP instead of traditional steel to circumvent the latter's corrosion issues. Despite a significant corpus of research on GFRP-reinforced structural members, questions about their compression behavior persist, making it a focal area of this review. This study evaluates the properties of GFRP bars and their impact on the structural behavior of concrete columns, addressing variables such as concrete type and strength, cross-sectional geometry, slenderness ratio, and reinforcement specifics under varied loading protocols. With a dataset spanning over 250 publications from 1988 to 2024, our findings reveal a marked increase in research interest, particularly in regions like China, Canada, and the United States, highlighting GFRP's potential as a cost-effective and durable alternative to steel. However, gaps in current knowledge, especially concerning Ultra-High-Performance Concrete (UHPC) reinforced with GFRP, underscore the necessity for targeted research. Additionally, the contribution of GFRP rebars to compressive column capacity ranges from 5% to 40%, but current design codes and standards underestimate this, necessitating new models and design provisions that accurately reflect GFRP's compressive behavior. Moreover, this review identifies other critical areas for future exploration, including the influence of cross-sectional geometry on structural behavior, the application of GFRP in seismic resistance, and the evaluation of the size effect on column strength. Furthermore, the paper calls for advanced studies on the long-term durability of GFRP-reinforced structures under various environmental conditions, environmental and economic impacts of GFRP usage, and the potential of Artificial Intelligence (AI) and Machine Learning (ML) in predicting the performance of GFRP-reinforced columns. Addressing these research gaps is crucial for developing more resilient and sustainable concrete structures, particularly in seismic zones and harsh environmental conditions, and fostering advancements in structural engineering through the adoption of innovative, efficient construction practices. [ABSTRACT FROM AUTHOR]

A novel material testing concept is developed in order to provide tensile and compressive properties within a single mechanical test. A new specimen geometry is designed for testing in a universal testing machine. Under tensile load, both a homogeneous tensile stress condition as well as a homogeneous compressive stress condition occur in the specimen. Measurements accompanying the experimental test with digital image correlation provide tensile and compressive Poisson's ratio as well as tensile modulus. These properties are input parameters for subsequent finite element simulations. The compressive modulus is determined by iteratively adjusting finite element simulations in order to couple experimental and simulated results. For validating the concept, experimental tests are carried out on polyoxymethylene. While the tensile Poisson's ratio of the new concept shows the best agreement with the reference value, the compressive modulus is approximately 15% higher. Further work should focus on an appropriate material model in order to reduce the deviation. [ABSTRACT FROM AUTHOR]

Using the approach proposed in Arlinskiĭ (Complex Anal Oper Theory 17(7):34, 2023), in an infinite-dimensional separable complex Hilbert space we give abstract constructions of families { T z } Im z > 0 of closed densely defined symmetric operators with the properties: (I) the domain of T z 2 is a core of T z , (II) the domain of T z 2 is dense but note a core of T z , (III) the domain of T z 2 is nontrivial but non-dense. For this purpose a class of maximal dissipative operators is defined and studied. The case dom T z 2 = { 0 } has been considered in Arlinskiĭ (Complex Anal Oper Theory 17(7):34, 2023). Given a densely defined closed symmetric operator S, in terms of the intersection of the domain of S with ran (S - λ I) and the projection of the domain of the adjoint S ∗ on ran (S - λ I) , λ ∈ C \ R , necessary and sufficient conditions for the cases (I)–(III) related to the domain of S 2 , are obtained. [ABSTRACT FROM AUTHOR]

When oil palm lumber is considered for load-bearing products such as glued laminated timber (GLT), defined strength and stiffness values are required. In this investigation, combined GLT from oil palm wood is tested in compression parallel and perpendicular and glulam lamellas in tension parallel to the vascular bundles. Strength and Young´s modulus in compression and tension parallel increase with the density by power law relationship. In contrast to dicotyle-dons, the strength in construction size exceeds that of small, defect-free test specimens (compression strength perpendicular), are in the same range (tensile and bending strength parallel) or only a little below (compression strength parallel). The specimen size does not influence the strength. The ratio of fc,0 : fm : ft,0 is 1.2 : 0.8 ... 1.7 ... 2.6 : 1 and fc,0 : fc,90 = 2.7 ... 13.0 ... 32.6 : 1 for ρ = 200 ... 400 ... 600 kg/m³; the ratio of Ec,0 : Em : Et,0 is 1.2 : 1.3 : 1 for ρ = 400 kg/m³. Ashby´s performance indices for minimum weight design rise with the density; the strength-density performance indices are comparable or only slightly lower than that for structural size softwood, whereas the modulus-density performance indices are much lower. The challenge in use of oil palm wood for load-bearing construction products is the low stiffness. [ABSTRACT FROM AUTHOR]

Treatment strategies for hard tissue defects aim to establish a mineralized microenvironment that facilitates tissue remodeling. As a mineralized tissue, cementum shares a similar structure with bone and exhibits an excellent capacity to resist resorption under compression. Macrophages are crucial for mineralized remodeling; however, their functional alterations in the microenvironment of cementum remain poorly understood. Therefore, this study explores the mechanisms by which cementum resists resorption under compression and the regulatory roles of cementoblasts in macrophage functions. As a result, extracellular vesicles from compression‐loaded cementoblasts (Comp‐EVs) promote macrophage M2 polarization and enhance the clearance of apoptotic cells (efferocytosis) by 2‐ to 3‐fold. Local injection of Comp‐EVs relieves cementum destruction in mouse root resorption model by activating the tissue repair function of macrophages. Moreover, Comp‐EV‐loaded hydrogels achieve significant bone healing in calvarial bone defect. Unexpectedly, under compression, EV secretion in cementoblasts is reduced by half. RNA‐Seq analysis and verification reveal that Rab35 expression decreases by 60% under compression, thereby hampering the release of EVs. Rab35 overexpression is proposed as a modification of cementoblasts to boost the yield of Comp‐EVs. Collectively, Comp‐EVs activate the repair function of macrophages, which will be a potential therapeutic strategy for hard tissue repair and regeneration. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM) represents a novel method for parts manufacturing, revolutionizing the design principles and processes. Among the different AM methods, fused filament fabrication (FFF) is one of the most widely employed and affordable, with numerous applications across a broad range of fields. Inherently, due to the fundamental physical mechanisms occurring during part building, the material acquires different properties compared to those of bulk material. Simultaneously, parameters such as the infill pattern and infill density significantly affect the overall behavior of the part. An efficient and effective tool to minimize the necessity for experimental investigations and to define the mechanical properties with respect to these parameters (i.e., infill density and pattern) is the finite element method (FEM). In the current study, accurate FEM models were developed and presented, considering the precise geometry of compression specimens for simulating the compression behavior of FFF-printed ASA polymer. More specifically, honeycomb infill patterns with different infill densities were simulated, and the results were validated by direct comparison to respective experimental results. It was deduced that utilizing an appropriate mesh size leads to higher precision and also increases the stability of the numerical simulation, while the FEM models can predict the loads as well as the deformed geometric shapes for different infill densities. As an overall conclusion, it is proved and reasoned that employing FEM and a proper modeling approach is indeed a feasible and efficient way to predict and define the compressive behavior of FFF parts. [ABSTRACT FROM AUTHOR]

AbstractIn this article we present an algorithm for faster computation of HMM likelihood gradients when the observation space is discrete. Many parameter estimation algorithms for HMM require repeated computation of gradient to optimize the likelihood function. Gradient computation is costly therefore its faster computation can improve their performance greatly. We develop an algorithm for faster computation of gradient using ideas from data compression. Our algorithm decreased computation cost of gradients by a factor of three to five. We apply our methods to speed up the Baum-Welch algorithm by similar factors. [ABSTRACT FROM AUTHOR]

Highlights Interpenetrating phase composites (IPCs) can combine the advantages of each component and have a good application prospect. IPCs were prepared by combining open‐cell aluminum foam (AF) and epoxy resin (EP) in three‐dimensional space in this study. Different contents of silica powder (SP, 80, 100, 120, and 140 wt%) were added to EP to improve the compressive and three‐point bending properties of IPCs. In the bending test, acoustic emission (AE) was applied to track the bending deformation of the samples, and k‐means clustering algorithm was applied to identify the damage modes. The compressive and bending properties of IPCs increased first and then decreased with the increase of SP content, and reached the maximum when the SP content was 100 wt%, with a compressive yield strength of 74.6 MPa and a bending peak load of 1.96 kN. The performance degradation was mainly attributed to the AF/EP debonding due to SP distribution at the interface. The X‐type shear band and EP/AF debonding appeared in compression failures of AF and IPCs, respectively. The AE clustering results showed that under bending load, plastic deformation of matrix (60–200 kHz) and fracture failure (230–340 kHz) modes appeared in AF, while EP/AF debonding (60–120 kHz), EP failure (120–230 kHz) and plastic deformation of foam matrix (230–250 kHz) modes appeared in IPCs. Silica powder was added to improve compressive and bending properties of IPCs. Acoustic emission was used to monitor bending of foam and IPCs firstly. k‐means clustering was used to identify and classify bending damage patterns. [ABSTRACT FROM AUTHOR]

Numerical simulations are essential for predicting the mechanical properties of different structures like gyroids that center this study. Three different methods are explored: shell elements, solid elements, and homogenization. Results reveal that homogenization is only suitable for obtaining the properties in the elastic zone, whereas solid models can determine also the behaviors in the plateau zone and the densification point. In the case of shell elements model, it can predict the elastic behavior model and the levels of stress in the plateau zone but with a lower accuracy than the solid element, but it cannot predict the densification point. [ABSTRACT FROM AUTHOR]

Introduction High-rate non-penetrating blunt impacts to the thorax, such as from impacts to protective equipment, can lead to a wide range of thoracic injuries. These injuries can include rib fractures, lung contusions, and abdominal organ contusions. Ovine animals have been used to study such impacts, in a variety of ways, including in silico. To properly model these impacts in silico, it is imperative that the tissues impacted are properly characterized. The objective of this study is to characterize and validate two tissues impacted that are adjacent to the point of impact—costal cartilage and hide. Heretofore, these materials have not been characterized for use in computational models despite their nearly immediate engagement in the high-rate, non-penetrating loading environment. Materials and Methods Ovine costal cartilage and hide samples were procured from a local abattoir following USDA regulations. Costal cartilage samples were then cut into ASTM D638 Type V tensile coupons and compressive disks for testing. The cartilage tensile coupons were tested at 150 ε/s, and the compressive samples were tested at −150 ε/s. Identical coupons and disks were then simulated in LS-Dyna using a hyperelastic material model based on test data and experimental boundary conditions. Hide samples were shaved and cut into ASTM D638 Type V tensile coupons and validated in silico using identical boundary conditions and an Ogden rubber model based on test data. Results The structural responses of costal cartilage and hide are presented and exhibit typical behavior for biological specimens. The respective model fits in LS-Dyna were a hyperelastic- based "simplified rubber" for the costal cartilage and an Ogden rubber for the hide. The costal cartilage had a mean failure strain of 0.094 ± 0.040 in tension and −0.1755 ± 0.0642 in compression. The costal cartilage was also noted to have an order-of-magnitude difference in the stresses observed experimentally between the tensile and compressive experiments. Hide had a mean failure strain of 0.2358 ± 0.1362. The energies for all three simulations showed material stability. Conclusions Overall, we successfully characterized the mechanical behavior of the hide and costal cartilage in an ovine model. The data are intended for use in computational analogs of the ovine model for testing non-penetrating blunt impact in silico. To improve upon these models, rate sensitivity should be included, which will require additional mechanical testing. [ABSTRACT FROM AUTHOR]

A passive daytime radiative cooling thin film material has been developed to provide the cooling source which requires no input, sustainable, and no pollutants or greenhouse gases emission. The thermally induced phase separation method and simple compression were used to prepare the compressed composite silica dioxide/polyethylene(SiO2/PE) aerogel films. The impact of SiO2 particle sizes and additions on the optical properties of composite films was investigated, and the internal microstructures and optical properties of the films were characterized. The optical properties of the films were enhanced by controlling the degree of compression. The results indicate that the addition of micro SiO2 is more favorable for increasing reflectance and nano SiO2 is more favorable for increasing emissivity, and the densification could result in emissivity enhancement and reflectance reduction. The optimal sample is achieved when the mass ratio of nano SiO2 to micro SiO2 to polyethylene is 0.5∶1∶1 and the compression ratio is one-ninth. This sample has a thickness of 0.5 mm, with 96.4% average reflectance of the solar spectrum and 95% average emissivity of the atmospheric window. The practical application performance of the sample was evaluated by testing its radiative cooling performance, antifouling and mechanical stability abilities. The experimental results show that the optimal sample achieves a significant temperature reduction of up to 6.5 ℃ compared to the sub-environment. This indicates that the SiO2/PE aerogel film has the ability to passively cool the sub-environment during both day and night, and that it has a contact angle with water of 127°, providing water resistance and potential self-cleaning properties in practical applications. [ABSTRACT FROM AUTHOR]

By constructing counterexamples, the authors show that the fixed subgroups are not compressed in direct products of free and surface groups, and hence negate a conjecture in [Zhang, Q., Ventura, E. and J. Wu, Fixed subgroups are compressed in surface groups, Internat. J. Algebra Comput., 25, 2015, 865–887]. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare average rate of oxygen consumption (VO2), slow component of oxygen consumption (VO2 drift), heart rate (HR) and rating of perceived exertion (RPE) while wearing compression pants vs. a control garment during long-distance running. Methods: Nine injury-free and recreationally active participants (32 ± 11 years) were recruited for this study. Participants ran in full-leg compression pants (COMP) and a loose-fitting control garment (CON). Participants ran in each condition for 40 min at a preferred submaximal speed. The rate of oxygen consumption (VO2) was measured continuously via a metabolic cart throughout each condition. Both HR and RPE were recorded every 5 min during each condition. Oxygen consumption was averaged across the entirety of the steady state during the 40 min conditions for analysis. Additionally, the average from the first five minutes of the steady state was subtracted from the average of the last five minutes to assess VO2. A paired t-test was used to assess for differences for both variables. Both HR and RPE were each compared between conditions using 2 (garment) × 8 (time) repeated measure ANOVAs (α = 0.05). Results: There were no differences between VO2 or VO2 drift while running with full-leg compression pants vs. the control garment (p > 0.05). Neither RPE nor HR were influenced by the garments (p > 0.05) or time (p > 0.05) during each condition. Conclusion: Wearing compression pants did not result in reduced VO2, VO2 drift, HR or RPE during a long-distance run. Although measured performance variables were not aided using compression pants, there were no negative effects to the use of compression pants. [ABSTRACT FROM AUTHOR]

A composite multifunctional radar absorption polymethacrylimide (RAPMI) foam sandwich (MRAPS) was constructed. Analytical models for out-of-plane and in-plane compression of the MRAPS were established. Three-dimensional failure mechanism maps and specific strength cubic cloud maps were drawn. Finally, a multiobjective particle swarm optimization (MOPSO) algorithm was used to achieve an integrated design, and a specific calculation example was tested and verified through experiments. The resulting sandwich with a 43.0 mm thickness core and 0.13 g/cm3 density achieves 90% effective absorption above broadband (RL ≤ −10 dB) in the 2–18 GHz range. As a radar absorption absorber, the MRAPS increased the engineering value and strategic importance of PMI foam for structural components in the military and aerospace sectors. [ABSTRACT FROM AUTHOR]

Background: Currently, low‐level evidence suggests loss of ambulation associated with acute thoracolumbar disk extrusion is best treated by decompressive spinal surgery. Conservative management can be successful, but the proportion of dogs that recover and the fate of herniated material are uncertain. Objectives: Determine the proportion of nonambulatory dogs with conservatively treated acute thoracolumbar disk extrusion that recover ambulation and measure the change in spinal cord compression during the first 12 weeks after presentation. Animals: Seventy‐two client‐owned nonambulatory dogs with acute thoracolumbar intervertebral disk extrusion. Methods: This is a prospective cohort study. Enrolled dogs underwent magnetic resonance imaging at presentation and owners were provided with conservative management recommendations. Imaging was repeated after 12 weeks. Recovery of ambulation was defined as 10 consecutive steps without falling. Spinal cord compression was determined from the cross‐sectional area of the vertebral canal and extradural compressive material at the lesion epicenter. The association between recovery and change in compression over the 12‐week observational period was examined. Results: Forty‐nine of fifty‐one (96%; 95% confidence interval [CI], 87%‐99%) of deep pain‐positive and 10/21 (48%; 95% CI, 28%‐68%) of deep pain‐negative dogs recovered ambulation within the 12‐week period. The median time to ambulation was 11 and 25 days for deep pain‐positive and ‐negative dogs, respectively. Reduction in spinal cord compression varied among individuals from minimal to complete and apparently was unrelated to the recovery of ambulation. Conclusions and Clinical Importance: A high proportion of conservatively treated dogs recovered ambulation after conservative management of acute thoracolumbar disk herniation. Recovery was not dependent on the resolution of compression. [ABSTRACT FROM AUTHOR]

Efficient dewatering plays a crucial role in land reclamation projects involving dredged slurry with high water content. Superabsorbent polymers (SAP), renowned for their exceptional water absorption capacity, have emerged as potential environmentally friendly and highly efficient dewatering agents for large-scale slurry dewatering. This study aims to investigate the compressive behavior of SAP-treated high water content slurry soils used in backfilling dredged soils. One-dimensional consolidation tests, starting from a low effective stress of 1.5 kPa, were conducted on mixtures of dredged slurry combined with SAP. The results reveal the significant influence of SAP on the virgin compression behavior of SAP-slurry mixtures, primarily attributed to alterations in soil fabric and the formation of an "apparent soil structure" in SAP-slurry mixtures with high initial water contents. The remolded yield stress σ′yr and the void ratio (eyr) at σ′yr of SAP-slurry mixtures are influenced by two key factors: (1) changes in the initial void ratio (eeq0) and the void ratio at liquid limit (eL), computed by considering the reconstituted soil without SAP, and (2) changes in "apparent soil structure" induced by SAP, quantified by a parameter associated with the swelling potential of SAP. Under effective vertical stress σ′v close to σ′yr, the loss of "apparent soil structure" exhibits two patterns: a sudden loss pattern with minimal deformation for 1–2% SAP and a gradual loss pattern with significant deformation for 3% SAP. Once the "apparent soil structure" disappears, the compression curves for slurries with different SAP contents can be effectively normalized using the intrinsic compression line (ICL) and extent intrinsic compression line (EICL). The intrinsic compression index C*c for SAP-slurry mixture correlates well with the observed variations in reconstituted soil, which considers the variation in eeq0 and eL. However, the SAP content tends to affect the compression parameter e*100, enlarging it for 1% and 2% SAP, while reducing it for 3% SAP. Based on the experimental data, a new empirical equation is proposed to normalize the variation of e*100 with eeq0 and eL for SAP-slurry mixtures. These findings emphasize the substantial improvement in the unfavorable properties of high water content slurry soils through the use of SAP, providing valuable theoretical and practical support for utilizing dredged soils as backfill materials. [ABSTRACT FROM AUTHOR]

Fire incidents pose significant threats to the structural integrity of reinforced concrete buildings, often necessitating comprehensive rehabilitation to restore safety and functionality. Effective rehabilitation of fire-damaged structures relies heavily on accurate damage assessment, which can be challenging with traditional invasive methods. This paper explores the impact of severe damage due to fire exposure on the mechanical behavior of steel-fiber-reinforced concrete (SFRC) using nondestructive evaluation (NDE) techniques. After being exposed to direct fire, the SFRC specimens are subjected to fracture testing to assess their mechanical properties. NDE techniques, specifically acoustic emission (AE) and ultrasonic pulse velocity (UPV), are employed to assess fire-induced damage. The primary aim of this study is to reveal that AE parameters—such as amplitude, cumulative hits, and energy—are strongly correlated with mechanical properties and damage of SFRC due to fire. Additionally, AE monitoring is employed to assess structural integrity throughout the loading application. The distribution of AE hits and the changes in specific AE parameters throughout the loading can serve as valuable indicators for differentiating between healthy and thermally damaged concrete. Compared to the well-established relationship between UPV and strength in bending and compression, the sensitivity of AE to fracture events shows its potential for in situ application, providing new characterization capabilities for evaluating the post-fire mechanical performance of SFRC. The test results of this study reveal the ability of the examined NDE methods to establish the optimum rehabilitation procedure to restore the capacity of the fire-damaged SFRC structural members. [ABSTRACT FROM AUTHOR]

The availability of a higher resolution fine spectral bandwidth in hyperspectral images (HSI) makes it easier to identify objects of interest in them. The inclusion of noise into the resulting collection of images is a limitation of HSI and has an adverse effect on post-processing and data interpretation. Denoising HSI data is thus necessary for the effective execution of post-processing activities like image categorization and spectral unmixing. Most of the existing models cannot handle many forms of noise simultaneously. When it comes to compression, available compression models face the problems of increased processing time and lower accuracy. To overcome the existing limitations, an image denoising model using an adaptive fusion network is proposed. The denoised output is then processed through a compression model which uses an optimized deep learning technique called "chaotic Chebyshev artificial hummingbird optimization algorithm-based bidirectional gated recurrent unit" (CCAO-BiGRU). All the proposed models were tested in Python and evaluated using the Indian Pines, Washington DC Mall and CAVE datasets. The proposed model underwent qualitative and quantitative analysis and showed a PSNR value of 82 in the case of Indian Pines and 78.4 for the Washington DC Mall dataset at a compression rate of 10. The study proved that the proposed model provides the knowledge about complex nonlinear mapping between noise-free and noisy HSI for obtaining the denoised images and also results in high-quality compressed output. [ABSTRACT FROM AUTHOR]

In this article, a kind of original bamboo-fiber reinforced phosphogypsum composite wall was proposed. The axial compression tests of eight walls and finite element analysis were carried out. The failure modes and mechanical properties of the walls were explored, the influence of parameters on the axial compression performance of the walls was studied, and the calculation methods of the axial compression capacity and stiffness of the composite walls were proposed. The results show that the phosphogypsum cracked first in the composite walls during the loading process, the cracks gradually spreaded through and widened, and the bamboo tubes inside the composite walls were crushed. The buckling failure occurred in the pure original bamboo wall. The bearing capacity of the composite wall control specimen is 140% and 38.46% higher than that of the pure phosphogypsum wall and the pure original bamboo wall, respectively. The number of dovetail nails has no significant effect on the axial compression performance of the composite wall. The bearing capacity and stiffness of composite wall increase with the increase of bamboo number, wall thickness, bamboo wall thickness and phosphogypsum strength. The calculation method of axial bearing capacity and stiffness of composite wall based on bamboo content is proposed. The finite element simulation results are in good agreement with the experimental and theoretical calculation results. The theoretical calculation method has high accuracy. The composite wall realizes the complementary advantages of original bamboo and phosphogypsum, which provides reference for the development and application of green buildings. [ABSTRACT FROM AUTHOR]