Earth Dam on Liquefiable Foundation and Remediation: Numerical Simulation of Centrifuge Experiments

A series of four dynamic centrifuge model tests was performed to investigate the effect of foundation densification on the seismic performance of a zoned earth dam with a saturated sand foundation. In these experiments, thickness of the densified foundation layer was systematically increased, resulting in a comprehensive set of dam-foundation response data. Herein, Class-A and Class-B numerical simulations of these experiments are conducted using a two-phase (solid and fluid) fully coupled finite element code. This code incorporates a plasticity-based soil stress–strain model with the modeling parameters partially calibrated based on earlier studies. The physical and numerical models both indicate reduced deformations and increased crest accelerations with the increase in densified layer thickness. Overall, the differences between the computed and recorded dam displacements are under 50%. At most locations, the computed excess pore pressure and acceleration match the recorded counterparts reasonably well. Based on this study, directions for further improvement of the numerical model are suggested.     

Energy Efficient Resource Migration Based Load Balance Mechanism for High Traffic Applications IoT

Wireless Personal Communications - Sound plays an important role in day to day life among all living organisms. It tells us about the environment, the characteristics of it, about people, place and...     

Expression of insulin,insulin-like growth factor I and glucocorticoid receptor in rat uterus and embryo during decidualization,implantation and organogenesis

The significance of insulin, insulin-like growth factor I (IGF-I) and glucocorticoids to the early mammalian embryo is clear in that they are key regulators of both mitogenic and metabolic effects during development. In the present study, the temporal sequence of expression of the respective receptor proteins was investigated for the first time in the developing rat utero-embryonic unit between conception and day 12 of gestation using immunocytochemistry. Insulin, IGF-I and glucocorticoid receptor were expressed in embryonic tissues after the start of implantation, and were co-localized in the primary ectoderm, extraembryonic ectoderm as well as in the ectoplacental cone. The parietal endoderm was devoid of glucocorticoid receptor staining, whereas IGF-I receptor was absent in visceral endoderm. After completion of basic organogenesis, the neural tube, notochord, otic placode, Wolffian duct, mesonephros and intestinal tube expressed insulin, IGF-I and glucocorticoid receptor. The glucocorticoid receptor was not expressed in heart tube and dorsal aortae. Considerable amounts of insulin receptor were detected in trophoblast-derived giant cells. In the uterus, luminal epithelium, endometrial stromal and myometrial smooth muscle cells immunoreacted with antisera against insulin, IGF-I and glucocorticoid receptor. Endometrial glands remained negative for the glucocorticoid receptor throughout the gestational period investigated. Uterine hormone receptor expression reached a peak at days 4 and 5 of gestation in endometrial stromal cells and decidua, respectively. In conclusion, the demonstrated ontogenetic pattern of insulin, IGF-I and glucocorticoid receptor expression indicates the potential sites of biological action of the respective ligands, providing supportive evidence for their critical importance during the course of embryogenesis in rats.     

Robust door assignment in less-than-truckload terminals

The assignment of incoming trailers to strip doors is one of the critical decisions that affect the performance of cross docking operations in less-than-truckload terminals. This paper introduces a mixed integer quadratic model with the objective of generating trailer-to-door assignments that equally distribute idle times at doors to accommodate operational level uncertainty encountered in truck arrival times. A door assignment heuristic is presented. The performance of the heuristic is compared with optimal solutions to small problems. The effectiveness of the proposed heuristic is studied under a variety of circumstances and terminal sizes. The simulation results show that the proposed heuristic is applicable to realistic-size terminals, and it is effective when variability in truck arrival and service times is considered.     

Building response to tunnelling- and excavation-induced ground movements: using transfer functions to review the limiting tensile strain method

In this paper, limiting tensile strain method (LTSM) is reviewed, and advantages and disadvantages resulted from the simplicity of this method are examined in the light of the findings of the existing experimental and numerical studies. Using the viewpoint of the transfer functions for the LTSM, a more independent sight for the interpretation of the relationships between deflection ratio, structure’s geometry, longitudinal/shear stiffness ratio and the limiting tensile strain is provided. In addition, the effect of average horizontal strain is included simply in the modified deep beam equations. Using reported data and observed damage classes of real and simulated case studies available in the literature, back-calculations for the coefficients of the transfer function are made. After comparing the back-calculated coefficients to the original coefficients of the LTSM, it is shown that observed damage and measured crack widths are reasonably compatible with the proposed limiting tensile strain boundaries. Also, it is shown that for the cases in which moderate or higher damage was observed, the original deep beam equations tend to underestimate the resultant damage.     

Prevention of biofouling on aquaculture nets with eco‐friendly antifouling paint formulation

Aquaculture, which is an important part of food supply, is usually carried out in cage nets made of textile materials. Fouling organisms settle on the cage nets over time, close the mesh openings, and cause unwanted weight gain. In order to prevent fouling, aquaculture nets are generally treated with antifouling paints. In this paper, warp knitted cage nets made from various raw materials were treated with three different antifouling paints. Econea was used as a biocide to prepare an eco‐friendly antifouling paint formulation, and two copper‐based commercial antifouling paints were supplied for comparison. Antifouling paint‐treated and untreated net samples were immersed in a marine ecosystem next to an aquaculture zone for 6 months. Settlement of fouling organisms on nets was observed by taking underwater photographs at periodic intervals. Following the field study, changes in the structure of the nets and antifouling performance of the paints were evaluated considering the results of underwater photographs, biomass growth, variation in mass and strength tests. Colour fastness of the antifouling paints to sea water was also measured to learn about biocide release and surface hydrophobicity. The results show that copper‐free eco‐friendly antifouling paint is just as effective against the fouling mechanism for all types of nets as copper‐based commercial antifouling paints. The novel eco‐friendly formulation has promising results, which provides an alternative for producers when considering the selection of raw materials.     

Feature Selection for Malware Detection on the Android Platform Based on Differences of IDF Values

Journal of Computer Science and Technology - Android is the mobile operating system most frequently targeted by malware in the smartphone ecosystem, with a market share significantly higher than...     

A Novel Approach of Perturb and Observe Technique Adapted to Rapid Change of Environmental Conditions and Load

Abstract

The basic P&O technique fails to track the MPP when a rapid change in luminosity and/or temperature has occurred because it cannot distinguish between disturbance of PV voltage and rapid change in environmental conditions. This study presents drawbacks of the basic algorithm and proposes a new variant of P&O with three incremental steps to differentiate the two states mentioned above, thus avoiding divergences in the MPPT path. The suggested MPPT command consists of a modified P&O algorithm applied to a boost converter to overcome poor transient responses and thus optimize the efficiency of the entire PV system. The proposed tracker is built using a 60?W module and its performance is verified by simulations with MATLAB tools considering quick change in the solar irradiance, temperature and load. The test results demonstrate the feasibility and improved performance of the system. The modified P&O technique effectively tracks the MPP in various work situations and capable of increasing energy transfer efficiency by nearly 5%.