مطالب

Wireless Sensor Networks (WSNs) have been employed in various real-time applications and addressed fundamental issues, such as limited power resources and network life. Several sensor nodes in a WSN monitor the actual world and relay discovered data to base stations. The biggest issue with WSN is that the sensors have a limited lifetime and use much electricity to relay data to the base station. This paper proposes an improved PSO-based Enhanced Distributed Energy Efficient Clustering (EDEEC) algorithm to extend the network's life and reduce power consumption. Clustering is the process of forming groups of sensor nodes. The cluster aims to improve the network's scalability, energy efficiency, and other characteristics. The particle swarm optimization algorithm is modified to obtain energy-efficient WSNs. The assessment is based on the essential WSN characteristics, including network lifetime and energy efficiency (power consumption). Compared to LEACH, HEED, and DEEC, our proposed IPSO-EDEEC uses less energy.

Financial markets are currently experiencing sharp volatility. Studying how the returns and volatility in one market affect other markets has always been one issue that helps investors and policymakers to make optimal decisions. Given the importance of volatility spillovers in the Iranian financial market, this study aimed to investigate the mechanisms behind the volatility spillovers in the foreign exchange, gold, and stock markets to the oil market in Iran. This descriptive study was conducted using the daily and monthly data from the oil, foreign exchange, gold, and capital markets from 2010 to 2019 and to analyze the data, ARCH and GARCH models have been used. The results of this study showed that the abnormal volatility of the foreign exchange and gold in the previous day positively affects the abnormal volatility of the oil market today, this indicates that money flows in the currency market, spilling over the fluctuations into the oil market. hey also found that the abnormal volatility of the capital market in the previous day negative affects the abnormal volatility of the oil market today, indicating that if money flows in the capital market, which indicates the flow of money in the capital market from yesterday, increasing the transfer of emotions to the current capital market but does not spillover into the oil market and volatility is not transferred into the oil market. Overall, the findings of this study confirmed the positive impact of the foreign exchange and gold markets on the abnormal volatility in the oil market in the short term (daily) and long term (monthly), but did not confirm the positive impact of the capital market on the abnormal volatility in the oil market.

Home businesses play a positive role in economic growth and development. Therefore, the development of the capabilities of these businesses is an important issue in economic success. The purpose of this research was to investigate the impact of entrepreneurial knowledge on the structure and performance of home businesses. In this research, the indirect effect of the structure of home businesses on the performance of these types of businesses has been investigated. The data used in the analysis of this study were collected from 139home business owners using a questionnaire. Data analysis was done using structural equation modeling method with PLS approach and questionnaire constructs show good validity and reliability. Previous knowledge of home business owners has a positive (β=0.392) and significant (T=2.289, >1.96) effect on business structure performance. Therefore, the first research hypothesis is supported. Previous knowledge of home business owners has a positive (β=0.597) and significant (T=6.310, >1.96) effect on the performance structure of home businesses. And therefore, the second hypothesis of the research is supported. The structure of home businesses has a positive (β=0.4) and significant (T=2.124, >1.96) effect on business performance. And therefore, the third hypothesis of the research is also supported.

Nowadays, according to the increasing trend of environmental changes and developments, organizations and companies need different strategic entrepreneurship models to respond effectively to their environmental needs. Therefore, this article is trying to systematically examine the findings of the studies conducted in this regard by using the meta-combination method and analyzing them based on the formation process and the output achievement. For this purpose, by referring to the reliable documents and documents available on the sites and checking the information from English sources from 2000 to 2019 and Persian from 2001 to 2019, among the mass of primary articles, 88 articles related to the research topic were identified. In order to analyze the selected articles, constituent concepts, and influential components, the content analysis method was used, and to validate the extracted concepts, the Delphi panel method was used with the presence of 8 experts. At the end of the research findings in the form of 5 components (leadership, attitude, resources, opportunism, and innovative learning), 10 sub-components (individual characteristics, management characteristics, organizational, cultural, social, financial, non-financial, the path of discovery and creation, exploitation, education and creativity and innovation) and 49 concepts were identified and classified. Also, the rank and importance of experts' opinions about the components of strategic entrepreneurship are in the order of leadership characteristics, opportunism, innovative learning, attitude, and resources.