This research aims to investigate and improve multi-user free space optic systems (FSO) based on a hybrid subcarrier multiplexing spectral amplitude coding-optical code division multiple access (SCM-SAC-OCDMA) technique using MS code with a direct decoding technique. The performance is observed under different weather conditions including clear, rain, and haze conditions. The investigation includes analyzing the proposed system mathematically using MATLAB and OptiSystem software. The simulation is carried out using a laser diode. Furthermore, the performances of the MS code in terms of angles of bit rate, beam divergence and noise are evaluated based on bit error rate (BER), received power, and transmission distance. The performance of the MS code-based system was subsequently compared with Khazani Syed code (KS), multi-diagonal (MD), and modified quadratic congruence code (MQC) codes under different weather conditions at a bit rate of 1 Gb/s and BER threshold of 10−9. Heavy rain indicates the worst performance in terms of transmission distance of 0.9 km. Nevertheless, the system designed using the MS code outperformed the KS, MD and MQC systems as it is capable of supporting up to 6.3, 0.8, 0.9, and 1.5 km, respectively, under clear weather. In conclusion, this study provides a means of improving FSO communications that suits tropical and Malaysia weather conditions.
A field study aimed at identifying the degree of satisfaction of secondary school principals with regard to the role of universities and their obstacles in developing their administrative skills. It adopted the descriptive analytical approach. The research community consisted of (249) male and female principals in the schools of Baghdad (Al-Rusafa and Karkh), and the research sample was chosen by the simple random stratified method at a percentage of (40%) of the research community, and the number of the sample was (100) male and female principals. A questionnaire consisting of (40) items distributed between two domains was developed. Its validity and reliability were confirmed. The researcher used the (SPS
... Show MoreAbstract As the United Nations approaches its 70th anniversary, the world is going through the most severe accumulation of serious international security failures in recent memory, challenging the UN Security Council’s ability to address them effectively. Over the past four years, crises in Libya, Syria and Ukraine have precipitated a worrisome erosion of great power relations that has complicated Security Council decision making on a number of trouble spots. Its inability to devise consensus responses to the escalating civil war in Syria has been particularly troubling, resulting in the regional spill over into Iraq and the emergence of Islamic State as a new threat to peace in the region and beyond. Meanwhile, the UN’s often under
... Show MoreAbstract:
Central banks seek to control and supervise credit and follow it up effectively due to the high credit risks surrounding it that may lead to damage to banks, and may even lead to damage to the reputation and confidence of the banking system as a whole.
The main role of supervisory control is to control credit by controlling it from excessive expansion during periods of economic inflation or its revitalization and improvement and expansion of credit transactions in cases of economic recession, or when central banks desire to support the national economy or support a sector of various
... Show MoreThe research aims to identify the most important difficulties facing the scientific research in the technical university in the financial, organizational and administrative according to the quality standards according to the paragraphs studied in the questionnaire questionnaire prepared for this purpose, including the research community on the Central Technical University, which includes several technical colleges and technical institutes were selected A sample of the researchers in the Institute of Technical Management where the number of training was 78 teachers took a random sample of researchers amounted to 40% of the questionnaire, and after the collection and classification of data were used statistical means, including the mean ar
... Show MoreThis century is witnessing changes in various fields,which have become a challenge to the enterprises in the contemporary business environment, the most important of which is the importance of measurement and disclosure of the role of knowledge capital in the transition to the knowledge economy, which is no longer the land and labor and physical capital resources the basic. Knowledge-based capital has emerged that provides the enterprise with an area of excellence and enhances its position to achieve competitive advantage. The research tackled the concept, objectives, components and importance of knowledge capital, which is fundamental in knowledge management, creating value added and enhancing competitiveness, as well as an
... Show MoreEncouraging micro-enterprises for comprehensive economic development are crucial to achieve the ambitious vision 2030 of the Kingdom of Saudi Arabia.
Small and Medium enterprises are inputting around 15.5 per cent to GDP while 33 per cent contribution as a private sector to Saudi Arabia's gross domestic product (GDP). This study aims to identify the most important factors that affect the efficiency of small enterprises in Saudi Arabia. To accomplish this objective, the study was conducted for small projects via the comprehensive inventory method under the supervision of the Institute of Entrepreneurship. A total of 282 questionnaires were collected from entrepreneurs and the differentiation analysis
... Show MoreBackground: Gotu Kola (Centella asiatica) has been used as a traditional medicine for many years to cure different kinds of diseases. Studies have been reported that Gotu Kola extracts might be used as a cure for oral diseases such as periodontal disease. In the present study, Gotu Kola leaves extracted with water will be used to evaluate its effect on some microorganisms living in the human saliva using minimum inhibitory concentration (MIC) method. Material and Method:Gotu Kola fresh leaves extract have been used with water as a solvent, a rotary evaporator was used to separate the solvent from the extract. The following microorganisms: Streptococci, Lactobacilli, and Staphylococcus aureus have been isolated fromthe Saliva of ten voluntee
... Show MoreThe present study aims to illuminate the assessment of the Turkish elite of the role of the Turkish media in forming the attitudes of public opinion vis a vis the attempted military coup of 15 July 2016. The authors utilized the survey method of a nominal sample of 315 individuals, equally distributed among the three foremost categories of the Turkish elite, namely: the political academic, and media elite. The foremost findings of the study are that the orientation of the coverage of the Turkish media of the events of the attempt military coup of 15 July, based on the perception and assessment of the Turkish elite, was positive to a high degree; it refuted the news and the inciting information given to foreign media revealed the bloodine
... Show MoreMany reports confirm ulcers as an adverse effect of drugs such as nicorandil and aspirin. The exact responsible mechanisms of ulceration have until now not proved. Mucosal ulcers associated with the onset of ulcer are manifested by an increase in proinflammatory cytokine, excessive prostaglandin, and up-regulation of Endothilin-1 level, which directly impacts the release of leptin. These, released locally within mucosal tissues, have played a role in controlling the extent of local inflammatory responses and processes of mucosal repair.
This study was designed to find out the correlation of plasma leptin and prostaglandin levels as a possible mechanism of oral ulcer formation as an adverse effect of nicorandil. The effect of nicorandi
Most modern legislations seeks to regulate the provisions that guarantee the stability of marital life, and that the Iraqi legislator along the lines of such legislation has ensured the stability of married life, therefore, he started to regulate the matters related to it, and in order to achieve these issues and the desired objectives, he adhered to limit these issues to periods that the parties must take into consideration when exercising these rights because they have serious effects that may lead to loss of these rights if they are not observed . In addition, the periods of personal status issues are divided into the considerations to several divisions included the related to their impact in terms of being constructing of the rights
... Show More