Hygienic engineering has dedicated a lot of time and energy to studying water filtration because of how important it is to human health. Thorough familiarity with the filtration process is essential for the design engineer to keep up with and profit from advances in filtering technology and equipment as the properties of raw water continue to change. Because it removes sediment, chemicals, odors, and microbes, filtration is an integral part of the water purification process. The most popular technique for treating surface water for municipal water supply is considered fast sand filtration, which can be achieved using either gravity or pressure sand filters. Predicting the performance of units in water treatment plants is a basic principle. For that reason, this research was executed to compare gravity and pressure sand filters in terms of construction, use, efficiency, filtration rate, cost, benefit, and drawbacks to predict the performance of those units under different conditions and from an economic standpoint. It also served as a presentation and review of previous studies dealing with the evaluation and development of pressure and gravity filters. This paper gives a brief overview of filtration theory, the types and properties of filter media, filter backwashing, and operational problems that can be avoided in the filtration process.
The metallicity [Fe/H] for several stars accompanied by Extra-solar planets were calculated and plotted as a function of stars mass (M*). Results showed that masses of Extra-solar planets stars are well correlated with their metallicity .This relation could be explained by the equation: Y=-0.0045x + 0.065. The metallicity limit is found to be in the range of (0.18 to 0.3), relative to the mass limit in the range of (0.76 to 1.44) MSun.
This criteria is a good tool that can be used by observers who are aiming for detecting Extra-solar planets
The research aims to identify the level of balance in the architectural thought influenced by the rational type human consciousness, the materialistic based on the Empirical type, moral based on human experience as source of knowledge.
This was reflected in architecture in the specialized thought that the mind is the source of knowledge which explains the phenomena of life. The rational approach based on objectivity and methodology in (Form Production), the other approach is based on subjectivity in form production (Form Inspiration).
The research problem is that there is imbalance in the relationship between the rational side and the human experience in architecture, which led into imbalance between theo
... Show MoreThe current study aimed to identify key consumer rights and the nature of the work of organizations and traders in the Algerian market through the opinions of the study sample. To prove the hypotheses the researcher depended on the data obtained by the questionnaire prepared for this purpose. She distributed 384 questionnaires out of which only 300 were returned.
The data were analyzed using several statistical techniques such as the Statistical Package for Social Studies system, in addition to percentages, frequencies, and standard deviation.
And a number of conclusions and recommendations were presented. The most important results are:
- There is a strong correlation between safety and compensation rights.
- There is a st
The current research aims to know the relationship between bullying and parental treatment. (200) pupils were selected randomly from the fifth and sixth grades of primary schools.
Two instruments were used. The first was to measure bullying and it included 19 items. To measure parental treatment, the researchers adopted (Aletaby 2001) scale.
Statistical analysis showed that correlation between bullying , wiggle and Firm treatment style was positive Statistically significant .Bulling was correlated negatively with (neglect, careless, and Authoritarian treatment style.
Praise be to God, Lord of the worlds, and the best of prayers. He has completed the delivery of our master Muhammad, his family, and all his companions. O God, bring us out from the darkness of illusion, honor us with the light of understanding, open us with knowledge of knowledge, facilitate our morals with dreams, and make us who listen to the saying and follow their best.
And after ..
Since ancient times, magic was mentioned in many books in the history of the civilizations of ancient peoples, where the first emergence of human civilizations, the oldest of which is the Mesopotamian civilization, the Chinese civilization, and the Pharaonic civilization in Egypt, where concepts prevailed based on the charlatans and sorcery an
... Show MoreIn this paper, a discrete SIS epidemic model with immigrant and treatment effects is proposed. Stability analysis of the endemic equilibria and disease-free is presented. Numerical simulations are conformed the theoretical results, and it is illustrated how the immigrants, as well as treatment effects, change current model behavior
sensor sampling rate (SSR) may be an effective and crucial field in networked control systems. Changing sensor sampling period after designing the networked control system is a critical matter for the stability of the system. In this article, a wireless networked control system with multi-rate sensor sampling is proposed to control the temperature of a multi-zone greenhouse. Here, a behavior based Mamdany fuzzy system is used in three approaches, first is to design the fuzzy temperature controller, second is to design a fuzzy gain selector and third is to design a fuzzy error handler. The main approach of the control system design is to control the input gain of the fuzzy temperature controller depending on the cur
... Show MoreIn this article, we design an optimal neural network based on new LM training algorithm. The traditional algorithm of LM required high memory, storage and computational overhead because of it required the updated of Hessian approximations in each iteration. The suggested design implemented to converts the original problem into a minimization problem using feed forward type to solve non-linear 3D - PDEs. Also, optimal design is obtained by computing the parameters of learning with highly precise. Examples are provided to portray the efficiency and applicability of this technique. Comparisons with other designs are also conducted to demonstrate the accuracy of the proposed design.