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World Wide Web is growing at a very fast pace and makes a lot of information available to the public. Search engines used conventional methods to retrieve information on the Web; however, the search results of these engines are still able to be refined and their accuracy is not high enough. One of the methods for web mining is evolutionary algorithms which search according to the user interests. The proposed method based on genetic algorithm optimizes important relationships among links on web pages and also presented a way for classifying web documents. Likewise, the proposed method also finds the best pages among searched ones by engines. Also, it calculates the quality of pages by web page features independently or dependently. The proposed algorithm is complementary to the search engines. In the proposed methods, after implementation of the genetic algorithm using MATLAB 2013 with crossover rate of 0.7 and mutation rate of 0.05, the best and the most similar pages are presented to the user. The optimal solutions remained fixed in several running of the proposed algorithm.

Nowadays, Military products of superpowers countries have a high level of diversity, delivery speed, and appropriative operational functionality. Therefore, Production of varied, high quality and high speed delivery military products, is essential for enhance Iranchr('39')s defensive deterrence power. Defense industries supply chain agility is an answer to how to produce military products with these features. This paper, with the aim of providing supply chain agility model in defense industries, first, identifies the most important supply chain agility practices, Then, using factor analysis, categorizes the practices and validates them based on structural equation modeling (SEM) and finally, using Interpretative Structural Modeling (ISM), presents a model that shows the relationships and hierarchy between these practices. The results show that out of a total of 62 practices introduced in the previous research for agile supply chain, 41 practices in the agility of the supply chain of defense industries are effective. These practices were classified in 8 categories include supplier relationship, workshop level management, organizational structure improvement, human resource management, product designing, improve and integrate the process, application of information technology, and customer relationship. Improvement of organizational structure was at the lowest level of the model. Therefore, managers first should focus on it.

Tender coconut water (TCW) is a natural plant product rich in phytochemicals and protects against toxic liver injury. However, the mechanism by which TCW inhibits inflammation and tissue damage is unknown. We examined the effect of TCW on primary rat hepatocyte viability, cytokine-induced gene expression and proinflammatory signaling in an in vitro model of sepsis. We observed that TCW improved hepatocyte viability and protected hepatocytes against cytokine-mediated cell death. TCW suppressed IL-1β-mediated increases in Nos2, Tnf, and Il6 mRNA and increased heme oxygenase 1 (HMOX1) protein. TCW inhibited iNOS expression through activation of AKT and JNK pathways since inhibition of PI3K and JNK signaling reduced TCW’s effect on iNOS protein expression and activity. These results demonstrate that TCW reduces proinflammatory gene expression and hepatocyte injury produced by elevated inflammatory cytokines and nitric oxide production.

Hypothesis: The dispersion state of nanoparticles cannot be evaluated accurately by rheological and mechanical testes because their agglomerates break down under applied stress leading to changes in their microstructure. Additionally, the contribution of interparticle interactions to macroscopic properties such as rheological and mechanical properties is still unclear. This is mainly due to the combined effects of interparticle interactions and the particle-polymer interactions. Microscopic measurements which can only provide information on a very small section of a sample are not reliable for this purpose. However, electrical tests as nondestructive methods can be used to assess the microstructure and cluster formation in nanocomposite structures. In addition, it is possible to detect separately the effect of filler-filler interactions using dielectric properties and with a proper choice of materials.Methods: In this study, ZnO/polystyrene (PS) nanocomposites were prepared through conventional mixing, dispersive mixing and surface particle treatment to control the particle dispersion states. The dispersion state of nanoparticles has been analyzed using their optical, electrical and rheological properties.Findings: The results showed that storage modulus increased with increasing filler dispersion, which could be attributed to the increase in interfacial layer and the higher modulus of nanocomposite relative to that of the bulk polymer matrix. The SEM images showed that the dispersive mixing and surface treatment of ZnO nanoparticles with oleic acid improved the dispersion of ZnO particles inside the PS matrix. On the other hand, increase in dispersion decreases the electrical conductivity and dielectric constant due to greater interparticle distance and reduction of dipole-dipole interactions, respectively. Hence, it is possible to detect the particle dispersion state by rheological and electrical properties.

Assessing the value of petrochemical industries on the one hand as strategic industries in the provision of raw materials of other parts and on the other hand, given the high weight of the formation of the stock market in Tehran, it is important. This industry, while influencing developments in other markets, especially the oil market, which has a significant impact on other markets, in particular the financial market. The stock prices of the petrochemicals in the stock market are heavily dependent on the price of petrochemical products, as well as the high dependence on oil price changes on global markets. Therefore, the analysis of the relationship between petrochemical price and oil price requires an asymmetrical model. In this study, the effect of oil price on value of the petrochemical industry in asymmetric shape in 2008-2017 periods daily basis has been analyzed using model Shin et al (2014). For this purpose, a nonlinear autoregressive distributed lag (NARDL) approach has been used. The findings indicate that these industries could be the channel for transferring global oil price fluctuations to the total stock market in Tehran. In the short term, anonymity is confirmed by the impact of the oil price on the value of the petrochemical industry. As oil prices decline, the value of petrochemicals decreases, but with increasing oil prices there will not be an increase in the value of petrochemicals. In the long run, oil prices are ............

Economic complexity is one of the criteria for measuring the knowledgebased economy of a country. Several studies have shown that improving the economic complexity index leads to sustainable economic growth and improved welfare. Therefore, policy makers tend to place the development and progress of the country in the path of knowledge-based economy and production of complex products. But the channel of influence of complexity on the economy of a country is questionable. Identifying this channel can lead to the focus of development policies. The hypothesis investigated in this research is the effectiveness of economic complexity on the field of factory activities. In the literature review, it was found that the relationship between these two variables is not predetermined. To test the hypothesis, a statistical sample including 46 countries has been selected for a period of 31 years ending in 2020. The PMG model has been used for data processing. The result of the estimation of the model shows that the increase in the added value of factory industries is one of the consequences of the improvement of economic complexity. This finding can help to set development policies. [ABSTRACT FROM AUTHOR]

Microcellular thermoplastic polyurethane foams are examined as absorbing materials in the X-band (8.2-12.4 GHz) frequency range by means of experiment. In this work, we aim to establish relationships between foam morphology including cell size and air volume fraction and electromagnetic properties including absorption, transmission and reflection quality. Nanocomposites based on thermoplastic polyurethane containing carbon black were prepared by coagulation method. In this procedure 15 wt% carbon black-containing nanocomposite was converted to microcellular foams using batch foaming process and supercritical carbon dioxide as physical foaming agent. The morphology of the foams was evaluated by scanning electron microscopy. S-parameters of the samples were measured by a vector network analyzer (VNA) and the effect of morphological parameters such as cell size and air volume fraction on the absorbing properties was investigated. We also established structure/properties relationships which were essential for further optimizations of the materials used in the construction of radar absorbing composites. Foaming reduced the percolation threshold of the nanocomposites due to the reduction in the average distance between nanoparticles. Foaming and dielectric constant reduction dropped the reflection percentage significantly. The increase in air volume fraction in the foam increased absorption per its weight, because of multiple scattering in composite media. The sensitivity of electromagnetic wave toward the variation of cell size is strongly weaker than that toward the variation of air volume fraction. Electromagnetic properties of the microcellular foams deviated a little from effective medium theories (EMTs). Air volume fraction of the cells was a function of cell size and smaller cells showed higher absorption.