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As digital communication technologies continue to grow and evolve, applications for this steady development are also growing. This growth has generated a growing need to look for automated methods for recognizing and classifying the digital modulation type used in the communication system, which has an important effect on many civil and military applications. This paper suggests a recognizing system capable of classifying multiple and different types of digital modulation methods (64QAM, 2PSK, 4PSK, 8PSK, 4ASK, 2FSK, 4FSK, 8FSK). This paper focuses on trying to recognize the type of digital modulation using the artificial neural network (ANN) with its complex algorithm to boost the performance and increase the noise immunity of the system. This system succeeded in recognizing all the digital modulation types under the current study without any prior information. The proposed system used 8 signal features that were used to classify these 8 modulation methods. The system succeeded in achieving a recognition ratio of at least 68% for experimental signals on a signal to noise ratio (SNR=5dB) and 89.1% for experimental signals at (SNR=10dB) and 91% for experimental signals at (SNR=15dB) for a channel with additive white gaussian noise (AWGN).

The procedure adopted for development of a survey instrument to measure the perceptions and attitudes of Saudi managers on the benefits laws has been described in this paper. The commonly adopted procedure of determining the scales and items for the survey was followed. The context-specific requirements were considered in determining the items to be included in the two scales. The full questionnaire contained relevant demographic items, eight items each for perceptions and attitudes measurement and a final open question for whatever the survey participants wished to say about the topic of survey. A pilot trial was done using the developed survey instrument to measure perceptions and attitudes of Saudi public sector managers on the benefits enjoyed by their workforce due to favourable labour laws. The results showed both perceptions and attitudes of managers to be positive. The results were explained in a number of different ways with the support of literature. Some limitations of this research, as scope for further research, have also been listed.

The aim of this systematic review was to review the methods adopted by corporates to avoid corporate tax, factors related to it and responses of countries to improve their compliance. Using Google Scholar with the topic as the search terms and different overlapping timeframes, the search yielded 68 papers. These were listed and briefly described. The common factors in these studies were tabulated for easy reference. It was a revelation in the way the corporates adopted methods to avoid sales tax. Papers dealing with policies, strategies and impact of sales tax on these corporates were in majority. Economic growth variables and their linkage to sales tax were the basis of study of some papers. Corporate social responsibility is an essential part of corporate finance and an attempt to link it with their tax compliance practice was the subject in some. Studies also covered the role of civic and interest groups in preventing evasion of tax as detrimental to society at large. An important aspect which came to light was that as long as there is competition among countries on tax matters and the existence of tax havens, a defiance of the tax laws and the tendency to avoid tax was noticed. Only a thorough reform of the tax laws in the countries will check these large scale evasions and bring more revenue where it is required. The need of the hour is a vigilant civil rights and interest group which can add pressure on the corporates to behave responsibly and ethically towards tax compliance. The implications that these changes will bring is huge as it prevents leakage of income which is rightly due to the governments. This study will help in plugging the loop holes and ensuring stricter compliance with the laws of the land.

Wireless sensor networks (WSNs) are a number of sensitive nodes senses a physical phenomenon at the position of their deployment then sends information to the base station to take appropriate operation. (WSNs) are used in many applications such track military targets, discover fires, study natural phenomena such as earthquakes, humidity, heat, etc. The nodes are spread in large areas and it is difficult to locate them manually because they are published randomly by planes or any other method and since the information received from sensitive nodes is useless without knowing their location in this case a problem resulted in the positioning of the nodes. So it unacceptable to equip each sensor node with global position system (GPS) due to various problems such as raises cost and energy consumption. In this paper explained a non-GPS technique to self-positioning of nodes in (WSNs) by using the multiple signal classification (MUSIC) algorithm to determine the position of the active sensor through estimated the direction of arrival (DOA) of the node signal. Then modified MUSIC algorithm (M-MUSIC) to solve the problem of coherent signal. MATLAB program successfully used to simulate the proposed algorithm.

Female reproductive aging is a normal phase of life that eventually leads to menopause and reproductive senescence. The current experimental investigation was intended to study zinc supplementation effects on early embryonic development and neonates in 26-28 weeks old female mice. In this investigation, 80 mature female mice were used that were divided into two groups of forty each. Two control groups received distilled water, while two Zn groups were given 0.115 mg/kg/day Zn orally daily during 2-3 estrous cycles. The female mice were all mated with adult males. Twenty female mice from both the control and Zn groups were euthanized by CO2 gas inhalation, and then a longitudinal incision in the abdomen of each female mouse was performed and uterine horns and oviducts were detached from the body in order to obtain two-cell embryos. On the other hand, 20 pregnant mice from each group were permitted to complete their pregnancy until birth and then their neonates were collected for macroscopic examination. The findings showed that the Zn supplementation significantly (P≤0.01) improved the mean embryonic development and the quality of 2-cell stage embryo grade A. Whereas, it decreased the mean embryonic development of 2-cell stage embryo grade D in aged female mice significantly (P≤0.01) in comparison with aged control groups. Also, the count and quality of neonates from Zn-treated aged female mice enhanced significantly (P≤0.01) as compared to non-treated aged female mice. It was concluded from these findings that the Zn can improve embryonic development and neonate count and quality in aged mice.

Internal Combustion Engines (ICE) are one of the most important engineering applications that operate based on the conversion of chemical energy from fuel into thermal energy as a result of direct combustion. The obtained thermal energy is then turned into kinetic energy to derive various means of transportation, such as marine, air, and land vehicles. The efficiency of ICE today is considered in the range of the intermediate level, and various improvements are being made to enhance its efficiency. The turbocharger can support the ICE, which works by increasing the pressure in the engine to enhance its efficiency. In this investigation, the effect of the turbocharger pressure on ICE performance was studied in the range of 2 to 10 bar. It was found that the increase in turbocharger pressure enhanced the pressure inside the engine, positively affecting engine efficiency indicators. Therefore, the increase in turbocharger pressure is directly proportional to the ICE efficiency. Doi: 10.28991/ESJ-2022-06-03-04 Full Text: PDF

The heat exchanger (HE) is a device that is used to complete the process of heat transfer between different matters without direct mixing. Therefore, it is of great importance in the transfer of energy and the completion of various energy transition processes. In the processes of HE between different energy systems, many factors influence and play a major and important role in the efficiency of transformation and exchange in forms of energy, such as the length, the material type, the exchange fluid, the surrounding environment, and many other factors. In this work, the effect of the HE length of the parallel and counter flow HEs was investigated based on the use of computer simulation programs. There was a significant impact of the exchange factors, especially the length of the HEs in both the parallel and counter-flow HEs, on the quality and efficiency of the HE and the temperature distribution. The overall evaluation shows that by increasing the length of the HE for both parallel and counter-flow HEs, the heat transfer is increased and the heat distribution becomes more homogeneous, which aids in enhancing the transfer of energy efficiency inside the HEs. Doi: 10.28991/ESJ-2022-06-01-010 Full Text: PDF