A Case Study on Expansive Soils and Rocks of Al-Khod in Northern Oman

A case study of damage due to expansive soils and rocks in Northern Oman has been studied. Geological and geotechnical investigation revealed the presence of very stiff to hard silty clay with mudstone. Swell pressures up to 330 kPa, and swell percent values up to 70 were measured. Smectite (montmorillonite) and illite clay minerals were identified as being the main clay minerals present in the soils and rocks. A detailed investigation into the damage to the different building elements has been undertaken to study the mechanism of structural damage to establish the cause of such damage and to recommend the appropriate measures to be taken for the construction of buildings founded on expansive soils and rocks in Oman

Residual Strength of Composite Unprotected Steel-Deck Floor Exposed to High Temperature (Fire Flame)

An experimental programme was conducted to find out the behaviour of composite SB-RC deck floors fabricated from three secondary steel beams welded to another two main beams topped with a concrete slab, exposed to high temperature (fire flame) of 300, 500 and 700ºC for 1 hour, then allowed to cool down by leaving them at lab condition to return to ambient temperature. The burning results show that, by exposing them to a fire flame of up to 300ºC, no serious amount of permanent deflection can result. It was also seen that the middle and lateral secondary steel beams have recovered 92 and 95% of the deflection caused by heating, respectively. While the recovered deflection of burned composite SB-RC deck floor at 500ºC was 46 and 45%, respectively. The greatest deterioration was in the exposure to 700ºC, as this leads to a higher permanent deflection of the middle and the lateral secondary steel beams, and the recovery percentage was only 11 and 18%, respectively. Then all composite SB-RC deck floors loaded till failure to determine percentage decrease in ultimate capacity. The results were compared with the behaviour of composite SB-RC deck floor without burning (control specimen). The comparison shows that the pre-burned composite SB-RC deck floor at 300, 500 and 700ºC, gives a decrease in specimens’ stiffness compared with the unburned one, by about 17, 61 and 74% for the middle secondary steel beam, and 25, 62 and 75% for the lateral ones, respectively. Also, linearity behaviour of the load-deflection curve decreases as the burning temperature increased. It was 15, 61 and 75% comparing with the unburned specimen, respectively. Also, the residual ultimate strength capacity decreases as the burning temperature was increased. For the burned composite deck floors at 300, 500 and 700°C, it was 87, 64 and 38%, respectively, compared with the unburned specimen.An experimental programme was conducted to find out the behaviour of composite unprotected steel beam-reinforced concrete SB-RC deck floors fabricated from three secondary steel beams welded to another two main beams topped with a reinforced concrete slab, exposed to high temperature (fire flame) of 300, 500 and 700ºC for 1 hour, then allowed to cool down by leaving them at lab condition to return to ambient temperature. The burning results show that, by exposing them to a fire flame of up to 300ºC, no serious amount of permanent deflection can result. It was also seen that the middle and lateral secondary steel beams have recovered 92 and 95% of the deflection caused by heating, respectively. While the recovered deflection of burned composite SB-RC deck floor at 500ºC was 46 and 45%, respectively. The greatest deterioration was in the exposure to 700ºC, as this leads to a higher permanent deflection of the middle and the lateral secondary steel beams, and the recovery percentage was only 11 and 18%, respectively. Then all composite SB-RC deck floors loaded till failure to determine percentage decrease in ultimate capacity. The results were compared with the behaviour of composite SB-RC deck floor without burning (reference specimen). The comparison shows that the pre-burned composite SB-RC deck floor at 300, 500 and 700ºC, gives a decrease in specimens’ stiffness compared with the unburned one, by about 17, 61 and 74% for the middle secondary steel beam, and 25, 62 and 75% for the lateral ones, respectively. Likewise, linearity behaviour of the load-deflection curve decreases and the curves become flatter as the burning temperature increased. Also, the residual ultimate strength capacity decreases as the burning temperature was increased. For the burned composite deck floors at 300, 500 and 700°C, it was 87, 64 and 38%, respectively, compared with the unburned specimen

A dramatic decline in university hospital admissions of acute rheumatic fever in the eastern region of Saudi Arabia

AbstractBackgroundsAcute rheumatic fever (ARF) and its sequel, chronic valvular heart disease are the most important causes for cardiovascular morbidity and mortality worldwide and mainly in developing countries. However, the incidence of ARF has declined in developed countries during the second half of 20th century.Material and methodsThe case files of all patients admitted as new cases of ARF over ∼11 years and 8 months, both in pediatric and medical departments of a university hospital located in the eastern region of Saudi Arabia were reviewed. The demographic and clinical data and the frequency of the new cases were compared with the data that have been published by us 10 years ago from the same hospital during a similar period of time (11 years and 8 months).ResultsIn the current study there was a significant decline in the frequency of admission of cases of ARF as compared to our previous study during a similar period of time, with a frequency rate of 12 cases per 100.000 hospitalizations versus 45 cases per 100.000 hospitalizations, respectively, P<0.001. Dyspnea and chest pain as clinical features of acute rheumatic carditis (ARC) were less frequent in the current study as compared to the previous study (35% versus 44%, P=0.02 and 10% versus 28.6%, P=0.031). The subgroup analysis revealed also a decreased frequency of the clinical features of ARC in pediatric age group in the current study as compared to our previous study.ConclusionThere is a significant decline in the frequency of new hospital admissions due to ARF. This decline was associated with similar decline in the frequency of the manifestations of ARC especially in pediatric age group (1–12 years)

Mode NASA blade used to calculate the power generator for (VAWT) by drag and lift coefficients

One of the confrontations with increasing demand on power in the entire world the methodologies of provided power divided into traditional methods against renewable methods. This article presents a simulation model to estimate the integrated power from vertical access wind turbine (VAWT) stages of development of a simulation model of local power supply system (LPSS) with (VAWT). However, wind power is one of the quickest developing advances for the sustainable power age. Disturbingly, in the ongoing years a few instances of corruption on telecommunication systems frameworks have emerged because of the presence of wind ranches, and costly and in fact complex restorative estimations needed. The grade of variation of power verified according to the grid size. The parameters were taken in the study through the preparation of the model are (efficiency, cost, and system response) compared to the benefits against disadvantages when combining the two systems to achieve a high performance of the power stability

Experimental Investigations on Combustion Pollutant Emissions of Sunflower Biodiesel and Its Blends with Diesel and Kerosene for Furnace Application

وقود الديزل الحيوي هو أحد أنواع الوقود البديلة الواعدة التي تستخدم في السيارات وتوربينات الغاز والأفران. في هذه الدراسة، تم تجريبيا اختبار وقود الديزل الحيوي وخلائطه (الديزل الحيوي-الديزل (Bx) ووقود الديزل الحيوي-كيروسين (Bkx)) باستخدام منظومة الاحتراق (البيرنر) المصنع للبحث. حيث تمت التجارب باستخدام مرذذ وقود نوع (airblast atomizer) وذلك للتحقق من خواص عملية الاحتراق خلال التجارب. تم اجراء التجارب ولجميع انواع الوقود عند قدرة 12.2 كيلو واط عند نسبة ترذيذ ثابته ALR=1 ودرجة حرارة 301K ولقيم نسب تكافؤ (0.6 الى 1.4). تم قياس الانبعاثات الناتجة عن عملية الاحتراق مثل CO2 وCO وNOx وUbH باستخدام محلل الانبعاثات Gas analyzer، حيث اظهرت النتائج ان الملوثات الرئيسية مثل CO2 وCO وUbH تنخفض بزيادة نسبة الوقود الحيوي (biodiesel) لزهرة عباد الشمس (SME)، كما انخفضت اكاسيد النتروجين المنبعثة. لذلك وحسب النتائج والاستنتاجات فان وقود الديزل الحيوي يمكن ان يكون بديلا جيدا للوقود الاحفوري.Biodiesel is one of the promising substitution fuels that are used in cars, gas turbine and furnace. In this study, the experiments liquid fuels used during the tests are biodiesel and its blends (biodiesel-diesel (Bx) and biodiesel-kerosene (Bkx)) in a furnace have been studied experimentally. An airblast atomizer was used to investigate the combustion properties. During the experiments, the heat rate is (12.2kW), the atomization-air to liquid fuel ratio (ALR = 1) and the constant air temperature is (301K) were maintained. For the range of equivalence ratio from 0.6 to 1.4, the characteristics of emission factors such as carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NOx) and unburned hydrocarbons (UbH) were measured experimentally. The results observed that the main pollutants such as CO2, CO, UbH were decreased with an increase in SME, while NOx emissions also decreased .Biodiesel could be a promising fuel for furnaces instead of fossil fuels

Advanced Flowrate Control of Petroleum Products in Transportation: An Optimized Modified Model Reference PID Approach

Efficient flowrate control is paramount for the seamless operation and reliability of petroleum transportation systems, where precise control of fluid movement ensures not only operational efficiency but also safety and cost-effectiveness. The main aim of this paper is to develop a highly effective modified model reference PID controller, tailored to ensure optimal flowrate control of petroleum products throughout their transportation. Initially, the petrol transportation process is analyzed to establish a suitable mathematical model based on vital factors like pipeline diameter, length, and pump attributes. However, using a basic first-order time delay model for petrol transportation systems is limiting due to inaccuracies, variable delay issues, safety oversights, and real-time control complexities. To improve this, the delay portion is approximated as a third-order transfer function to better reflect complex physical conditions. Subsequently, the PID controller is synthesized by modifying its structure to address flowrate control issues. These modifications primarily focus on the controller’s derivative component, involving the addition of a first-order filter and alterations to its structure. To optimize the proposed controller, the genetic, black hole, and zebra optimization techniques are employed, aiming to minimize an integral time absolute error cost function and ensure that the outlet flow of the controlled system closely follows the response of an appropriate reference model. They are chosen for their proficiency in complex optimization to enhance the controller's effectiveness by optimizing parameters within constraints, adapting to system dynamics, and ensuring optimal conditions. Through simulations, it is demonstrated that the proposed controller significantly enhances the stability and efficiency of the control system, while maintaining practical control signals. Moreover, the proposed modifications and intelligent tuning of the PID controller yield remarkable improvements compared to previous related work, resulting in a 36% reduction in rise time, a 63% reduction in settling time, an 80% reduction in overshoot, and a 98% reduction in cost value

Design and implementation of an oil leakage monitoring system based on wireless network

Monitoring pipeline leaks is one of the recent hot studies. Leakage may occur because of time corrosion in the tube raw materials. To reduce the negative consequences of this leak, an effective leak detection system is used to prevent serious leakage accidents and damage in oil pipelines. Buildings, ecosystems, air pollution, and human life are all at risk in case of leakage occurs which could lead to fires. This paper introduces one of the research methods for the detection of pipeline leaks with a particular focus on software-based methods. The computer board interface (CBI) and wireless sensor networks have been used beside Arduino as a micro-monitor for the entire system. ZigBee is also utilized to send read data from sensors to the monitoring system displayed on the LabVIEW graphical user interface (GUI). The operator can take direct action when a leak occurs. The effectiveness of the leakage monitoring process and its practical use are demonstrated by the introduction of computerized techniques based on pressure gauge analysis on a specific pipeline in the laboratory. The result showed that the system is widely covered, accurate data transmission and robust real-time performance which reduces economic losses and environmental pollution

Induced Sputum Substance P in Children with Difficult-to-Treat Bronchial Asthma and Gastroesophageal Reflux: Effect of Esomeprazole Therapy

Objectives. To assess the induced sputum substance P (ISSP) levels in children having difficult-to-treat asthma (DA) with and without gastroesophageal reflux (GER). We aimed also to evaluate the association of GER with childhood DA, relationship of GER severity with childhood asthma control test (C-ACT), FEV1, peak expiratory flow (PEF) variability, and ISSP. Finally, we tried to evaluate esomeprazole treatment effect on C-ACT and FEV1 in children with DA. Methods. Spirometry, C-ACT, upper gastrointestinal endoscopy, and ISSP measurement were done for children with DA compared to healthy controls. Results. ISSP was high in DA with higher levels in the group having associated GER. In the latter group, ISSP and C-ACT improved significantly after esomeprazole treatment while FEV1 and PEF variability did not improve. Reflux severity was positively correlated with ISSP and negatively correlated with FEV1. Conclusions. GER was found in 49% of our patients with childhood DA. Very high ISSP levels in children with DA may be used as a marker for presence of GERD. Esomeprazole therapy improved asthma symptoms but did not improve lung function