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The purpose of this paper is to present elastic buckling behaviour of simply supported and clamped thin rectangular isotropic plates having central circular cutouts subjected to uniaxial partial edge compression. Analysis is carried out for four different kinds of partial edge compression and it is extended to study the effect of aspect ratio of plate on buckling load.

A finite element method technique is used in the current work to solve the buckling problem of plate using eight node quadrilateral element and plate kinematics based on first order shear deformation theory. Results obtained from finite element analysis are first validated for isotropic square plates, without cutouts, subjected to uniaxial partial edge compression with some earlier published literature.

From the current work it is concluded that the buckling strength of square plates is highly influenced by partial edge compression, as compared to plate subjected to uniform edge compression; but with increase in aspect ratio, influence of partial edge compression on plate buckling load decreases.

This paper usefully shows how partial edge compression of plates affects the buckling strength of plate having circular cutouts. Generally, simply supported plates subjected uniaxial partial edge compression of Type I and Type III are found to be stronger than plates subjected to partial edge compression Type II and Type IV, respectively.

Auxetics metamaterials show high performance in their specific characteristics, while the absolute stiffness and strength are much weaker due to substantial porosity. This paper aims to propose a novel auxetic honeycomb structure manufactured using selective laser melting and study the enhanced mechanical performance when subjected to in-plane compression loading.

A novel composite structure was designed and fabricated on the basis of an arrowhead auxetic honeycomb and filled with polyurethane foam. The deformation mechanism and mechanical responses of the structure with different structural parameters were investigated experimentally and numerically. With the verified simulation models, the effects of parameters on compression strength and energy absorption characteristics were further discussed through parametric analysis.

A good agreement was achieved between the experimental and simulation results, showing an evidently enhanced compression strength and energy absorption capacity. The interaction between the auxetic honeycomb and foam reveals to exploit a reinforcement effect on the compression performance. The parametric analysis indicates that the composite with smaller included angel and higher foam density exhibits higher plateau stress and better specific energy absorption, while increasing strut thickness is undesirable for high energy absorption efficiency.

The results of this study served to demonstrate an enhanced mechanical performance for the foam filled auxetic honeycomb, which is expected to be exploited with applications in aerospace, automobile, civil engineering and protective devices. The findings of this study can provide numerical and experimental references for the design of structural parameters.

Recycled concrete is an economical and environmentally friendly green material. The shear performance of recycled concrete load-bearing masonry is studied, which is great of significance for its promotion and application and also has great significance for the sustainable development of energy materials.

In total, 30 new load-bearing block masonry samples of self-insulating recycled concrete are subjected to pure shear tests, and 42 samples are tested subjected to shear-compression composite shear tests. According to the axial design compression ratio, the test is separated into seven working conditions (0.1–0.8).

According to the test results, the recommended formula for the average shear strength along the joint section of recycled concrete block masonry is given, which can be used as a reference for engineering design. The measured shear-compression correlation curves of recycled concrete block masonry are drawn, and the proposed limits of three shear-compression failure characteristics are given. The recommended formula for the average shear strength of masonry under the theory of shear-friction with variable friction coefficient is given, providing a valuable reference for the formulation of relevant specifications and practical engineering design.

Simulated elastoplastic analysis and finite element modeling on the specimens are performed to verify the test results.

The purpose of this paper is to understand compression garment in the area of medical industry, compression garments were used initially for patients with circulatory problems. External pressure was created by compression garments on the body surface which prevents blood clots, leg swelling and improves venous hemodynamics.

Compression rehabilitation is a significant element in the effective management of lower limb problems of people associated with venous, lymphatic, fat disorders like lipoedema.

Compression garments have been attributed primarily for the increase in blood flow, improvement in recovery, reduction in muscle vibration that increase stability, improvement in thermoregulation, decrease in muscle pain, elimination of blood lactate and creatine kinase after exercise.

Compression garments are extraordinary clothes that contain elastomeric yarns or fibers that are responsible for applying significant mechanical pressure on the required body surface for compressing, stabilizing and supporting underlying tissues.

With the advent of technology, a huge amount of data is being transmitted and received through the internet. Large bandwidth and storage are required for the exchange of data and storage, respectively. Hence, compression of the data which is to be transmitted over the channel is unavoidable. The main purpose of the proposed system is to use the bandwidth effectively. The videos are compressed at the transmitter’s end and reconstructed at the receiver’s end. Compression techniques even help for smaller storage requirements.

The paper proposes a novel compression technique for three-dimensional (3D) videos using a zig-zag 3D discrete cosine transform. The method operates a 3D discrete cosine transform on the videos, followed by a zig-zag scanning process. Finally, to convert the data into a single bit stream for transmission, a run-length encoding technique is used. The videos are reconstructed by using the inverse 3D discrete cosine transform, inverse zig-zag scanning (quantization) and inverse run length coding techniques. The proposed method is simple and reduces the complexity of the convolutional techniques.

Coding reduction, code word reduction, peak signal to noise ratio (PSNR), mean square error, compression percent and compression ratio values are calculated, and the dominance of the proposed method over the convolutional methods is seen.

With zig-zag quantization and run length encoding using 3D discrete cosine transform for 3D video compression, gives compression up to 90% with a PSNR of 41.98 dB. The proposed method can be used in multimedia applications where bandwidth, storage and data expenses are the major issues.

Stretch fabrics are employed to create compression in garments for medical, sports, and fitness applications. Although potential correlations between wearing compression garments and physiological or performance metrics have been studied, such correlations require knowledge of the actual compression caused by garments. The purpose of this paper is to demonstrate, compare, and contrast different methods for measuring compression delivered by an exemplar compression garment.

The exemplar compression garment is a plain jersey knit maternity band. The compression delivered by this garment was determined via three different methods – Tekscan pressure mapping system, Hohenstein Measurement System (HOSY), and a fabric-based analytical model employing uniaxial fabric tensile data.

HOSY and the fabric-based model, assuming a circular cross section for the garment, provided comparable results for compression versus garment height. However, these methods did not capture the varying compression delivered at different transverse locations when the subject was noncircular in cross section. Assuming an elliptical cross section, the fabric-based model predicted results that were comparable to those measured by the Tekscan system: for example, compressions were approximately 130-160 percent greater at the hip, and approximately 60-100 percent lower at the posterior, than HOSY revealed. Further, the Tekscan system allows the effect of movement on compression to be captured.

This paper compares and contrasts three compression measurement methods and demonstrates the importance of angular position and height dependencies. Further, the fabric-based model is presented as a tool to assist design of compression garments.

The conception of a compression garment that applies a desired interface pressure level has been a great challenge for therapists and compression garment manufacturers even today. The purpose of this study is to develop a new method for designing a compression legging that exerts Class I interface pressure to the lower limb.

This research presents a new method for the design of Class I compression garment. It consists of theoretically calculating the circumferences of the Class I compression legging based on the reduction factors. To assess the effectiveness of the method, we used both objective and subjective evaluations. For the objective evaluation, we have developed a measuring device to measure Class I legging interface pressure in different measuring points using a force pressure sensor. Concerning the subjective evaluation, 10 healthy female subjects agreed to take part in this study in order to evaluate the ergonomic comfort when wearing the designed compression legging.

Participating subjects delivered their feeling about comfort and motion restriction during the use of the legging. Referring to the volunteers’ answers, the Class I compression legging can be described as comfortable and has a satisfactory fit during wear.

The important feature of this study was the effectiveness of the new designing method in producing a compression legging that delivers the desired amount of pressure and offers a comfort sensation during wear. The outcome of this research is a new method that could be used to create a variety of compression garments that can apply different pressure levels.

The aim of this paper is to investigate the regularities and longevity of the recovering without takedown of the friction pairs in internal combustion engines using the lubricants with metal cladding materials (MCM).

Recovering of friction pairs of internal combustion engines by MCM was investigated using field experiments. Four automobiles were investigated. The wear of those details was evaluated according to the compression in the cylinders. The influence of MCM on the amount of toxic materials (carbon monoxide and hydrocarbons) in the exhaust gas was evaluated after measurements with a gas analyser.

Using MCM can recover on average 60 per cent of lost compression ΔP_m. MCM decreases compression dispersion among separate cylinders of the engine. Compression of recovered engine cylinders decreases according to logarithmic function. Increment of cylinders' compression ΔP_d decreased on average 40‐50 per cent after 10,000 km car run. The recovering of the details of a cylinder‐piston group with MCM decreases the emission of toxic exhaust gas to the environment.

No laboratory investigations of MCM regeneration of friction pairs were performed which could evaluate the influence of different factors on the regeneration quality.

Investigations on the use of MCM for recovering the cylinder‐piston details of engines show the expedience in using such materials during periodic technical service of engines when the lubricants are changed.

Investigations of regenerating engines by MCM using field experiments were performed for the first time.

The paper aims to shed some light on the effect of the notch/crack‐tip stresses and their role on the cyclic plasticity and crack growth behavior in compression‐compression fatigue.

Compression precracking was studied using 2D finite element analysis for CT specimen. The final crack length and the shape of the crack front were compared with those obtained experimentally.

It has been found that cyclic plasticity and stress redistribution govern the observed fatigue crack growth behavior in compression‐compression precracking. Only the internal stress corresponding to P_max shows a significant redistribution with the crack extension whereas the stress corresponding P_min is not affected by the increase of crack length.

This results are limited to Mode I cracking.

It supports that two thresholds, ΔK^th and K_max^th, govern the fatigue crack behavior. When the contribution from the internal tensile stress is not big enough to make K_max exceed K_max^th the crack will self arrest.

It has been found that cyclic plasticity and stress redistribution govern the observed fatigue crack growth behavior in compression‐compression precracking. The comparison of the numerical results with experimental data in terms of final crack length and crack front shape indicated a fair agreement.

This paper aims to propose a fast machine compression scheme, which can solve the problem of low-bandwidth transmission for underwater images.

This fast machine compression scheme mainly consists of three stages. Firstly, raw images are fed into the image pre-processing module, which is specially designed for underwater color images. Secondly, a divide-and-conquer (D&C) image compression framework is developed to divide the problem of image compression into a manageable size. And extreme learning machine (ELM) is introduced to substitute for principal component analysis (PCA), which is a traditional transform-based lossy compression algorithm. The execution time of ELM is very short, thus the authors can compress the images at a much faster speed. Finally, underwater color images can be recovered from the compressed images.

Experiment results show that the proposed scheme can not only compress the images at a much faster speed but also maintain the acceptable perceptual quality of reconstructed images.

This paper proposes a fast machine compression scheme, which combines the traditional PCA compression algorithm with the ELM algorithm. Moreover, a pre-processing module and a D&C image compression framework are specially designed for underwater images.