A design for a photovoltaic-thermal (PVT) assembly with a water-cooled heat sink was planned, constructed, and experimentally evaluated in the climatic conditions of the southern region of Iraq during the summertime. The water-cooled heat sink was applied to thermally manage the PV cells, in order to boost the electrical output of the PVT system. A set of temperature sensors was installed to monitor the water intake, exit, and cell temperatures. The climatic parameters including the wind velocity, atmospheric pressure, and solar irradiation were also monitored on a daily basis. The effects of solar irradiation on the average PV temperature, electrical power, and overall electrical-thermal efficiency were investigated. The findings indicate that the PV temperature would increase from 65 to 73 °C, when the solar irradiation increases from 500 to 960 W/m2, with and without cooling, respectively. Meanwhile, the output power increased from 35 to 55 W when the solar irradiation increased from 500 to 960 W/m2 during the daytime. The impact of varying the mass flow rate of cooling water in the range of 4 to 16 L/min was also examined, and it was found that the cell temperature declines as the water flow increases in intensity throughout the daytime. The maximum cell temperature recorded for PV modules without cooling was in the middle of the day. The lowest cell temperature was also recorded in the middle of the day for a PVT solar system with 16 L/min of cooling water.
Recurrent strokes can be devastating, often resulting in severe disability or death. However, nearly 90% of the causes of recurrent stroke are modifiable, which means recurrent strokes can be averted by controlling risk factors, which are mainly behavioral and metabolic in nature. Thus, it shows that from the previous works that recurrent stroke prediction model could help in minimizing the possibility of getting recurrent stroke. Previous works have shown promising results in predicting first-time stroke cases with machine learning approaches. However, there are limited works on recurrent stroke prediction using machine learning methods. Hence, this work is proposed to perform an empirical analysis and to investigate machine learning al
... Show MoreTigris River is the lifeline that supplies a great part of Iraq with water from north to south. Throughout its entire length, the river is battered by various types of pollutants such as wastewater effluents from municipal, industrial, agricultural activities, and others. Hence, the water quality assessment of the Tigris River is crucial in ensuring that appropriate and adequate measures are taken to save the river from as much pollution as possible. In this study, six water treatment plants (WTPs) situated on the two-banks of the Tigris within Baghdad City were Al Karkh; Sharq Dijla; Al Wathba; Al Karama; Al Doura, and Al Wahda from northern Baghdad to its south, that selected to determine the removal efficiency of turbidity and
... Show MoreThis paper aims to evaluate large-scale water treatment plants’ performance and demonstrate that it can produce high-level effluent water. Raw water and treated water parameters of a large monitoring databank from 2016 to 2019, from eight water treatment plants located at different parts in Baghdad city, were analyzed using nonparametric and multivariate statistical tools such as principal component analysis (PCA) and hierarchical cluster analysis (HCA). The plants are Al-Karkh, Sharq-Dijlah, Al-Wathba, Al-Qadisiya Al-Karama, Al-Dora, Al-Rasheed, Al-Wehda. PCA extracted six factors as the most significant water quality parameters that can be used to evaluate the variation in drinkin
Traditional tree management is laborious and costly, thus this work aimed to study the performance of two different types of frond cutting saws (reciprocating saw and vibrating saw) and examine the two saws on five date palm varieties. Four parameters were examined, including cutting time for a single frond, the power needed for cutting a single frond, frond cutting productivity expressed as tree/h, and vibration conveyed to the worker’s hand. A field experiment was designed according to the nested randomized complete block design, including five date palm varieties as the main plot and the type of saw as a sub-plot. Means were compared using the least significant differences (LSD 0
The research aims to identify the effect of applying administrative decentralization to an educational performance by assessing educational performance before and after the process of transferring powers from the federal government (the Iraqi Ministry of Education) to local governments (governorates) as well as identifying the appropriate central or decentralized administrative system to advance the educational reality and performance. To achieve the goal of the research, educational data was collected and analyzed, as well as the measurement of educational performance indicators and analysis during two phases, the first represents the stage of applying the central system and spanned between the academic year (2011-2012) and the
... Show MoreBackground: The most crucial mechanism of genetic variation in N. meningitidis is the slipped strand mispairing, this mechanism generates Phase variation using simple sequence repeat (SSR) and is commonly used by the N. meningitidis to escape the immune system despite its function in eradicating the pathogenic and commensal bacteria. Some of simple sequence repeats (SSRs) that located within the genome works as phase variation while other SSRs have no role in generating phase variation mechanisms. Therefore, Aim: the main goal of the current in silico study was to detect the probability of SSR to enroll with phase variation for the entire N. meningitidis genome. Methods: Different criteria were used to judge SSR as
... Show MoreResearchers need to understand the differences between parametric and nonparametric regression models and how they work with available information about the relationship between response and explanatory variables and the distribution of random errors. This paper proposes a new nonparametric regression function for the kernel and employs it with the Nadaraya-Watson kernel estimator method and the Gaussian kernel function. The proposed kernel function (AMS) is then compared to the Gaussian kernel and the traditional parametric method, the ordinary least squares method (OLS). The objective of this study is to examine the effectiveness of nonparametric regression and identify the best-performing model when employing the Nadaraya-Watson
... Show MoreStylistics represents a modern approach in understanding the literary text through the linguistic patterns that form it. The distinctive phenomena that the text includes constitute special features in it. As well as exploring its aesthetic aspects through description and analysis at the same time. The close link between stylistics and linguistics made stylistics occupy a prominent place in modern literary criticism.
In this regard, we do not want to dwell on the different directions of stylistics. Rather, we will prolong the discussion in the study of the style as a (deviation. Aversion) from the original. Because this trend plays on the chord of the paradox between the surface structure and the deep structure, especially when the sur
In this investigation, deep eutectic solvent based on propionic acid and choline chloride was used to prepare polyaniline, polypyrrole, and poly(aniline-co-pyrrole) samples using chemical oxidation and polymerization. Quantum mechanical calculations were conducted using time-dependent density functional theory to determine the electronic, spectroscopic properties and structure of homopolymers and the copolymer which were compared with the respective experimental data. Furthermore, the synthesized materials were characterized using Fourier transform IR spectroscopy, scanning electron microscopy (SEM), UV-visible spectroscopy, and thermogravimetric analysis. IR and UV-visible spectra confirmed copolymerization, and SEM revealed that the copol
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