Finite and infinite element method applied to water wave diffraction problems

In this work, three types of infinite elements are developed to solve the problem of linear water wave diffraction by objects in a 2D unbounded domain. The infinite elements, which model the far field wave potential stretching to infinity, are coupled to conventional finite elements, which model the near field wave potential. This coupling greatly economises the finite element analysis. The original mapped infinite element, due to Zienkiewicz et al [102], is improved to model objects of large aspect ratio more economically. This infinite element (Type 1) can now be used on the exterior of an ellipse (or other shapes) rather than a circle circumscribing the object. The element is validated by solving the problem of diffraction of water waves by an ellipse with different angles of wave incidence. The results are compared with their equivalent analytical solutions and the errors are very small being less than 1.0%.The wave envelope approach, due to Astley et al [9], is employed to develop a simple mapped wave envelope infinite element. The element mass, stiffness and damping matrices are derived from first principles using the weighted residual approach. This element (Type 2) can also be used on the exterior of any shapes. The element is validated by solving the problem of wave diffraction by circular and elliptical vertical cylinders for different angles of wave incidence. The results are compared with their equivalent analytical solutions and again the errors are very small. The problem of wave diffraction by multiple objects is also considered. A new wave envelope mapped infinite element (Type 3) is developed to tackle such a problem. Examples involving diffraction of water waves by arrays of circular and elliptical cylinders are solved. For circular cylinders, the results are compared with their equivalent analytical solutions which show excellent agreement. A comparison is made between the three types of infinite elements by solving the diffraction of waves by circular and elliptical vertical cylinders. The results show that all three types of infinite elements can give accurate results in the near field for a given single diffracting object. Type 1 would be a preferable choice in situations where computing resource is the main concern and reliable solutions are required only in the near field. Type 2 or 3 would give very accurate solutions both in the near and far fields. Type 3 is the most suitable choice for modelling any number, shape and configuration of bodies

Comparison of Effectiveness of Topiramate and Diazepam in Preventing Risk of Recurrent Febrile Seizure in Children underAge of 2 Years

  Background and Objective: Febrile seizures are the most common type of convulsions. Medicinal prophylaxis is sometimes used for children at high risk of recurrent febrile seizure. In certain circumstances, conventional drugs such as diazepam and phenobarbital cannot be used and the need for alternative medicines is felt. This study set out to compare the effectiveness of topiramate and diazepam in preventing the risk of recurrent febrile seizure in children under the age of 2 years.Methodology: This was a randomized controlled trial. The research sampleincluded 54 patients, at risk of recurrent febrile seizure,who were inhibited from taking phenobarbital. After selection, they were randomly divided into two groups. The first group received diazepam treatment during fever episodes and the second group received daily dose of topiramate.  A one-year follow-up of recurrent febrile seizure and its complications was also conducted.Findings: Thirty four patients (17 patients in each group) completed the one-year course of the trial. Recurrent febrile seizure was not observed in the course of preventive treatment. The prevalence of minor complications was 29.4% in the diazepam group and 48.5% in the topiramate group.No major complication was observed in among the subjectsConclusion: Topiramate can be recommended for preventing recurrent febrile seizure when the use of front line medicines is not possible

The problem of scheduling surgery room with approach of maximizing preferences of hospital management and surgeons: A case study in Saadi Hospital of Isfahan

In present age, medical system is changing and transforming in terms of position and these changes include increasing speed of patients and population aging and in its respect, increasing the elderly. Regarding technical barriers and limitations of human resources at hand in hospitals, major part of patients cannot be treated immediately and respectively, how longer time patients wait for treatment, their satisfaction about hospital services will decrease. In other hand, hospitals and especially state hospitals suffer a massive budget deficit. This limitation led to this matter that hospitals look for increasing medical service efficiency and decreasing cost of medical services. It should be pointed that the purpose of these hospitals is nothing but balancing and integrating budget. Based on obtained results, 70% of referrals to hospitals were aimed to surgery operations and more than 15% of wasted time in hospitals was related to surgery rooms and this instance clears importance of surgery room and its proper benefit more than before. Surgery room and generally surgery department has a special sensitivity and it is considered as the most vital section in hospitals. Therefore, the smallest deficiency or disregarding specified plan and pre-determined standards result in problems. Hence, hospital surgery room can be resembled with hospital motor because many hospital resources such as managers of surgery room planning, anesthesia specialist surgeons, nurses and others whom probably have different and sometimes conflicting goals are dependent on surgery room and eventually surgery room planning. The goal of this paper is the problem of surgery room scheduling with approach of maximizing surgeons and devoting surgery time based on hospital preferences and each of surgeons. Therefore, a model is provided to their scheduling in order to preferences and decreasing overtimes. In such a way that each surgeon operates in a surgery room specified for the same type of surgery regardless of surgery teams and based on predicted times for each surgery. This proposed model is solved in shape of a problem using obtained data from Saadi hospital of Isfahan and using Lingo software

The problem of scheduling surgery room with approach of maximizing preferences of hospital management and surgeons: A case study in Saadi Hospital of Isfahan

In present age, medical system is changing and transforming in terms of position and these changes include increasing speed of patients and population aging and in its respect, increasing the elderly. Regarding technical barriers and limitations of human resources at hand in hospitals, major part of patients cannot be treated immediately and respectively, how longer time patients wait for treatment, their satisfaction about hospital services will decrease. In other hand, hospitals and especially state hospitals suffer a massive budget deficit. This limitation led to this matter that hospitals look for increasing medical service efficiency and decreasing cost of medical services. It should be pointed that the purpose of these hospitals is nothing but balancing and integrating budget. Based on obtained results, 70% of referrals to hospitals were aimed to surgery operations and more than 15% of wasted time in hospitals was related to surgery rooms and this instance clears importance of surgery room and its proper benefit more than before. Surgery room and generally surgery department has a special sensitivity and it is considered as the most vital section in hospitals. Therefore, the smallest deficiency or disregarding specified plan and pre-determined standards result in problems. Hence, hospital surgery room can be resembled with hospital motor because many hospital resources such as managers of surgery room planning, anesthesia specialist surgeons, nurses and others whom probably have different and sometimes conflicting goals are dependent on surgery room and eventually surgery room planning. The goal of this paper is the problem of surgery room scheduling with approach of maximizing surgeons and devoting surgery time based on hospital preferences and each of surgeons. Therefore, a model is provided to their scheduling in order to preferences and decreasing overtimes. In such a way that each surgeon operates in a surgery room specified for the same type of surgery regardless of surgery teams and based on predicted times for each surgery. This proposed model is solved in shape of a problem using obtained data from Saadi hospital of Isfahan and using Lingo software

Analysis between financial leverage with the stock price and the operational performance of the accepted companies in Tehran’s stock market

In this study, the relationships between the changes of the economic leverage and the operational performance of the accepted companies of Tehran’s stock market were analyzed. The main goal of this study is to determine if there is a meaningful relationship between the changes of the economic leverage and the operational performance of the accepted companies of Tehran’s stock market. For this purpose, 145 companies from 2005 to 2006 with systematic elimination method were selected. The results indicated that there was a meaningful relationship between the economic leverage and the stock price. The results showed that an increase in the debt led to an increase in the relationship between the economic leverage and the stock price. Also, the study showed that the relationship between the economic leverage and the stock price is a meaningful and negative relationship. Finally, the study indicated the change of the economic leverage and the ratio of expenses to property is a negative and meaningful relationship

The problem of scheduling surgery room with approach of maximizing preferences of hospital management and surgeons: A case study in Saadi Hospital of Isfahan

In present age, medical system is changing and transforming in terms of position and these changes include increasing speed of patients and population aging and in its respect, increasing the elderly. Regarding technical barriers and limitations of human resources at hand in hospitals, major part of patients cannot be treated immediately and respectively, how longer time patients wait for treatment, their satisfaction about hospital services will decrease. In other hand, hospitals and especially state hospitals suffer a massive budget deficit. This limitation led to this matter that hospitals look for increasing medical service efficiency and decreasing cost of medical services. It should be pointed that the purpose of these hospitals is nothing but balancing and integrating budget. Based on obtained results, 70% of referrals to hospitals were aimed to surgery operations and more than 15% of wasted time in hospitals was related to surgery rooms and this instance clears importance of surgery room and its proper benefit more than before. Surgery room and generally surgery department has a special sensitivity and it is considered as the most vital section in hospitals. Therefore, the smallest deficiency or disregarding specified plan and pre-determined standards result in problems. Hence, hospital surgery room can be resembled with hospital motor because many hospital resources such as managers of surgery room planning, anesthesia specialist surgeons, nurses and others whom probably have different and sometimes conflicting goals are dependent on surgery room and eventually surgery room planning. The goal of this paper is the problem of surgery room scheduling with approach of maximizing surgeons and devoting surgery time based on hospital preferences and each of surgeons. Therefore, a model is provided to their scheduling in order to preferences and decreasing overtimes. In such a way that each surgeon operates in a surgery room specified for the same type of surgery regardless of surgery teams and based on predicted times for each surgery. This proposed model is solved in shape of a problem using obtained data from Saadi hospital of Isfahan and using Lingo software

The Effects of Implicit and Explicit Focus on Form on Oral Accuracy of EFL Learners

The current study was an attempt to reexamine the effectiveness of two kinds of form-focused instruction on oral accuracy of EFL learners. Participants of the current study were 41 male students in two experimental groups and a control group. During twelve sessions of treatment, to the first experimental group (class A), the target forms were taught implicitly through input enhancement (Implicit teaching). In the second class (class B), the grammatical structures were taught in explicit manner through metalinguistic explanation. However, to the control group (class C) no focus on form instruction was applied. A pre-test and a post-test were designed in interview model to test the oral accuracy of the learners both before and after treatment. In order to analyze the obtained scores from pre-test and post-test, paired sample T-Test was used to study the scores within each group, while one-way ANOVA was employed to study the mean variance between groups. The results showed that although both methods were beneficent, post-test scores of the students to whom the forms were taught explicitly were significantly higher than students to whom the forms were taught implicitly

Analysis between financial leverage with the stock price and the operational performance of the accepted companies in Tehran’s stock market

In this study, the relationships between the changes of the economic leverage and the operational performance of the accepted companies of Tehran’s stock market were analyzed. The main goal of this study is to determine if there is a meaningful relationship between the changes of the economic leverage and the operational performance of the accepted companies of Tehran’s stock market. For this purpose, 145 companies from 2005 to 2006 with systematic elimination method were selected. The results indicated that there was a meaningful relationship between the economic leverage and the stock price. The results showed that an increase in the debt led to an increase in the relationship between the economic leverage and the stock price. Also, the study showed that the relationship between the economic leverage and the stock price is a meaningful and negative relationship. Finally, the study indicated the change of the economic leverage and the ratio of expenses to property is a negative and meaningful relationship

Cytotoxicity effects of green synthesized silver nanoparticles on human colon cancer (HT29) cells

Background: Nowadays, investigations on the role of nanoparticles for diagnosis, and treatment of cancers are being increased. This study aimed at examining the cytotoxic effect of green synthesized silver nanoparticles (AgNPs) on human colon cancer (HT29) and normal (HEK293) cells using the Artemisa tournefortiana extract. Materials and Methods: In the current study, the green synthesis of AgNPs was conducted using the A. tournefortiana extract. Then, the characterization of fabricated AgNPs was performed by ultraviolet-visible (UV-vis) spectroscopy, X-ray diffraction (XRD), and transmission electron microscopy (TEM) methods. The HT29 and HEK293 cell lines were treated with different concentrations of synthesized AgNPs for 24 hours and the viability of cells and half-maximal inhibitory concentration) IC50( were calculated by the MTT assay. Results: The fabricated AgNPs showed the characteristic surface plasmon resonance peak at around 425 nm. The crystallographic shapes from the XRD and TEM tests showed that the AgNPs were mostly spherical in shape, having an average diameter of 22 nm. The MTT results revealed that AgNPs significantly decreased the viability of cells in dose-and time-dependent manner. The IC50 values of nanoparticles for HT29 and HEK293 cell lines, during the 24 hours, were 40.71 and 61.38 mg/mL, respectively. Conclusion: According to the results of the current study, the green fabricated AgNPs can have a more cytotoxic effect on colon cancer cells compared to the normal cells. Thus, they can be considered as a promising strategy for the treatment of colon cancer

Analysis between financial leverage with the stock price and the operational performance of the accepted companies in Tehran’s stock market

In this study, the relationships between the changes of the economic leverage and the operational performance of the accepted companies of Tehran’s stock market were analyzed. The main goal of this study is to determine if there is a meaningful relationship between the changes of the economic leverage and the operational performance of the accepted companies of Tehran’s stock market. For this purpose, 145 companies from 2005 to 2006 with systematic elimination method were selected. The results indicated that there was a meaningful relationship between the economic leverage and the stock price. The results showed that an increase in the debt led to an increase in the relationship between the economic leverage and the stock price. Also, the study showed that the relationship between the economic leverage and the stock price is a meaningful and negative relationship. Finally, the study indicated the change of the economic leverage and the ratio of expenses to property is a negative and meaningful relationship