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Shikoku Electric Power Co., Inc. has developed the technology to manufacture a brand name "Finash" about 12 years ago, by sorting and classifying coal ash generated in coal fired power plants. "Finash" is highly functional fly ash (HFA) is produced by removing irregular coarse particles. It is important for the production of HFA to minimize the variation in quality of coal ash with sophisticated classification technique and extracting good-quality spherical fine particles. It is now widely utilized as concrete admixture for general civil engineering structures and buildings in Japan. When highly functional fly ash (HFA) is used as shotcrete admixture to substitute for fine aggregate of 100kg/m³, the shotcrete has the advantages of decreasing the amount of dust and rebound during spraying operation, improving the hardened properties of concrete, etc. Therefore, it has been applied in many tunnel construction projects. This paper discusses about the various characteristics such as construction placement, strength, neutralization and dry shrinkage of shotcrete using highly functional fly ash (HFA), using the results that is obtained from spray test in an actual road tunnel.

Dam concrete suffers from serious abrasion damages in southwestern China, the abrasion resistance of concrete is therefore one of the most important factors determining the reliability even the safety of the dams. In the present work, the effects of fly and/or silica fume on the mechanical properties, drying shrinkage, as well the cracking and abrasion resistance of concrete were investigated, then the pore structures of concrete added with fly ash and silica fume and the pore surface fractal dimensions ($D_s$) were determined by the mercury intrusion porosimetry (MIP) method and a fractal model, respectively. Finally, the relationships between the abrasion resistance of concrete and the porosity as well as the $D_s$ were revealed and discussed. The results indicate that silica fume significantly increases the drying shrinkage especially at early age, while the incorporation of fly ash and silica fume together can decrease the early plastic shrinkage-induced cracking risk and the final shrinkage to some degrees. Besides, the utilization of 5wt.% silica fume and 20wt.% fly ash together increases the abrasion resistance and mechanical property by about 4–9% at various ages. In addition, the compressive strength and the abrasion resistance of concrete are linearly correlated with the concrete porosity and the $D_s$. Both the fly ash and silica fume could decrease the porosity of concrete and increase the $D_s$, therefore the concrete containing fly ash and silica fume have desired mechanical property and abrasion resistance. Moreover, $D_s$ has a more profound effect on the abrasion resistance of concrete than the concrete porosity. The addition of 5wt.% silica fume and 20wt.% fly ash together is suitable for the concretes used for wearing surfaces in terms of mechanical property, cracking and abrasion resistance.

This research work is an insight into the various properties of liner materials utilized in landfill sites to control the leachate. Although expansive clay soil is inorganic, it is problematic. The soil owes this aspect to erratic fluctuations in its behavior due to the movement of water. Urbanization, increase in population and industries generate enormous amounts of waste in different forms. Disposal of these wastes in the landfill without any scientific manner creates a major problem to the surrounding soil and groundwater. In this study, an attempt was taken to identify the effect of soil properties and groundwater quality due to the continuous generation of leachate in the dumping sites. To prevent such an environmental problem, highly impermeable sand–bentonite mixture is used as a liner material in the waste disposal sites. Therefore, various mixtures of sand–bentonite were prepared by varying sand contents and different sieve sizes, i.e. 2–0.075mm; 2–0.425mm and 0.425–0.075mm were used. And also to improve the strength and hydraulic conductivity of the liner materials, discrete random fiber is mixed with various proportions to these mixtures and examined.

The paper discusses finite sample properties of optimal portfolio weights, estimated expected portfolio return, and portfolio variance. The first estimator assumes the asset returns to be independent, while the second takes them to be predictable using a linear regression model. The third and the fourth approaches are based on a shrinkage technique and a Bayesian methodology, respectively. In the first two cases, we establish the moments of the weights and the portfolio returns. A consistent estimator of the shrinkage parameter for the third estimator is then derived. The advantages of the shrinkage approach are assessed in an empirical study.

In this paper, an evaluation of the influence of atmospheric humidity on the critical buckling load of reinforced concrete columns is performed. A particular case consisting of a real, extremely slender reinforced concrete pole was taken for the study. The chosen mathematical procedure for calculating the critical load is based on the Mechanics of Deformable Solids due to variations of structure vibration frequency over time. The rheological behavior of concrete related to creep and shrinkage, which illustrates the time-dependent aspect of the problem, was also considered in the analysis following normative recommendations from the Brazilian Association of Technical Standards (ABNT). In order to evaluate value changes of critical buckling loads, different time instants after loading the structure as well as different relative humidity from 0% to 100%, in 10% increments were considered. According to the selected criteria, it was possible to verify that a higher atmospheric humidity decreases the water transport from the interior out to the exterior surfaces of concrete, hence positively influencing structure stiffness. Therefore, the lowest reduction on critical buckling was 41.9% at 100% relative atmospheric humidity, versus the highest 60.7% at 0% relative humidity. A period of 7500 days after loading the structure was considered in the analysis.

Speckles are inherent to SAR. They hide and undermine several relevant information contained in the SAR images. In this paper, a despeckling algorithm using the shrinkage of two-dimensional discrete orthonormal S-transform (2D-DOST) coefficients in the transform domain along with shock filter is proposed. Also, an attempt has been made as a post-processing step to preserve the edges and other details while removing the speckle. The proposed strategy involves decomposing the SAR image into low and high-frequency components and processing them separately. A shock filter is used to smooth out the small variations in low-frequency components, and the high-frequency components are treated with a shrinkage of 2D-DOST coefficients. The edges, for enhancement, are detected using a ratio-based edge detection algorithm. The proposed method is tested, verified, and compared with some well-known models on C-band and X-band SAR images. A detailed experimental analysis is illustrated.

This paper presents a systematic methodology to determine optimal injection molding conditions for minimum warpage and shrinkage in a thin wall relay part using modified particle swarm optimization algorithm (MPSO). Polybutylene terephthalate (PBT) and polyethylene terephthalate (PET) were injected in a thin wall relay component for different processing parameters: melt temperature, packing pressure and packing time. Further, Taguchi’s L₉ (3${}^2)$ orthogonal array is used for conducting simulation analysis to consider the interaction effects of the above parameters. A predictive mathematical model for shrinkage and warpage is developed in terms of the above process parameters using regression analysis. ANOVA analysis is performed to establish statistical significance within the injection molding parameters. The analytical model is further optimized using a newly developed MPSO algorithm and the process parameters values are predicted for minimizing shrinkage and warpage. The predicted values of shrinkage and warpage using MPSO algorithm are improved by approximately 30% as compared to the initial simulation values and comparable to previous literature results.

Wavelet has become an appealing image processing technique, due to the fact that the sparseness of wavelet expansion is equivalent to smoothness measure in Besov spaces so that the regularization of image can be performed by manipulating its wavelet coefficients. Unfortunately, wavelets have good performance especially at representing point singularities, but they fail to efficiently represent object edges. As one of computational harmonic analysis tools, curvelets have an essentially optimal representation of objects which is C² away from a C² edge. In this paper, we first apply constraint of curvelet-type decomposition spaces as a regularizing term to variational model for image denoising. Based on the equivalent relationship between semi-norm of curvelet-type decomposition spaces and the weighted curvelet coefficients, solution to the proposed model approximately equals to different curvelet shrinkages. As a second contribution, we also propose another image restoration model from image decomposition point of view. Furthermore, an equivalent theorem of two proposed models is given. Finally, the experiment results show the superiority of proposed models over traditional wavelet-based ones.

The purpose of this study is to investigate the effect of composition poly(D,L-lactide-co-glycolide)/poly(ε-caprolactone) (PLGA/PCL) blending on the morphology, shrinkage and degradation behaviors of the electrospun fibers. With the increase of PLGA content in the composite fibers, the average diameter of the electrospun fibers increased from 1.35 μm to 1.95 μm. The serious shrinking of the electrospun PLGA meshes could be circumvented by adding 20% PCL in the fibers, resulting from the semi-crystalline nature of PCL. The degradation rate of the electrospun meshes could be modulated by PLGA/PCL composition. In addition, the electrospun meshes containing 20% PCL displayed stable dimensional morphology with degradation.

This paper presents the results of an experimental study of the percolation behavior of the complex dielectric constant of ceramic matrix composites (CMC). Samples of piezoactive CMC were obtained by joint sintering of synthesized PZT piezoceramic powder (matrix) and crushed particles of sintered PZT piezoceramics (filler) of different compositions. The experimental dependencies of real and imaginary parts of the complex dielectric constant of CMC on the porosity of piezoceramic matrix and volume content of ceramic filler particles were measured and analyzed. It was shown that the additional porosity of the ceramic matrix resulting from sintering of the CMC masks the dielectric percolation transition, that actually occurs at the volume concentration of ceramic filler close to percolation threshold (V ∼ 1/3).

In this paper a new ripplet-based shrinkage technique is used to suppress noise from Magnetic Resonance Imaging (MRI). The propitious properties of ripplet transform such as anisotropy, high directionality, good localization, and high-energy compaction make the proposed method efficient and feature preserving when compared to other transforms. Ripplet transform provides efficient representation of edges in images with a higher potential for image processing applications such as image restoration, compression, and de-noising. The proposed method implies a new nonlinear ripplet-based shrinkage technique to extract the spatial and frequency information from MRI corrupted by noise. The choice of this new shrinkage technique is due to its simplicity, versatility, and its efficiency in removing noise from homogenous regions and those regions with singularities, when compared to the existing filtering techniques. Experiments were conducted on several diffusion weighed images and anatomical images. The results show that the proposed de-noising technique shows competitive performance compared to the current state-of-art methods. Qualitative validation was performed based on several quality metrics and profound improvement over existing methods was obtained. Higher values of Peak Signal to Noise Ratio (PSNR), Correlation Coefficient (CC), mean structural similarity index (MSSIM), and lower values of Root Mean Square Error (RMSE) and computational time were obtained for the proposed ripplet-based shrinkage technique when compared to the existing ones.

The aims of this study were to investigate a novel strategy for drying longan without stone viz. the two-stage drying using a superheated steam dryer followed by a hot air dryer (SSD/HAD), both from heat/mass transfer and product quality points of view. The experiments were performed in the two different stages of SSD/HAD using the superheated steam temperatures of 120-180°C in the first-stage and then the drying air temperatures of 60-70°C in the second-stage. The moisture content of longan at the end of the superheated steam drying stage was 200% dry basis. The effects of drying medium temperatures and the intermediate moisture content of dried longan after SSD/HAD on the drying kinetics and quality of dried longan were investigated. The quality of longan was evaluated in terms of its color characteristics and shrinkage.

The objective of the present study was to investigate the effects of various parameters, i.e., concentration of salt solution (2, 3, 4% (w/v)), boiling time (3, 5, 7 minutes) and drying air temperature (80, 100, 120°C) on the kinetics of drying and various quality attributes of shrimp, namely, color, texture, shrinkage and rehydration ability, during drying in a jet-spouted bed dryer. Small shrimp (350-360 shrimp/kg) was boiled and then dried until its moisture content was around 25% (d.b.). It was found that the color changes, toughness and shrinkage of shrimp increased while the rehydration ability decreased with an increase in the concentration of salt solution and boiling time.

The influences of shell mould preheating temperature, shell mould wall thickness and pouring temperature on the casting defects (including porosity and shrinkage) of cast steel elbows were systematically investigated by using InteCAST/CAE simulation. The results demonstrate that the volume of the porosity or shrinkage defects in the casting steel elbows decreases with increasing the shell mould wall thickness, preheating temperature and pouring temperature.

According to current shrinkage prediction mode, four kinds of concrete shrinkage prediction models (CEB-FIP 90, ACI 209 (92), RILEM B3 and GL2000) are selected to analyze in this paper. Based on the same shrinkage conditions, some important parameters of four shrinkage modes are analyzed and regular pattern of shrinkage are summarized.

A basic research on shrinkage resistance of recycled coarse aggregate concrete subjected to different substitution rate was carried out. In this experiment, there were 30%, 40%, 50%, 70% natural stone substituted by recycled coarse aggregate and part of cement replaced by active admixture. The results showed that autogenous shrinkage, total shrinkage and drying shrinkage develop rapidly in the early age, and the shrinkage of concrete increased along with the amount of recycled coarse aggregate increased while the benchmark water-binder ratio was under the same circumstance.