Structural Behavior of Composite Reinforced Ferrocement Plates

The results of an experimental investigation to examine the structural behavior of composite reinforced ferrocement concrete plates are presented in this paper. The precast permanent ferrocement forms are proposed as a viable alternative to the steel panels in some of its uses. The experimental program comprised casting and testing of eighteen reinforced ferrocement plates having the dimensions of 550mm width, 1100mm length and different thicknesses (60, 80,100) mm. Each control plate was reinforced with four steel bars of 6mm diameter at the bottom of the plate and six steel bars of 6mm diameter at the transverse direction. Two types of steel mesh were used to reinforce the ferrocement plates. These types are: galvanized welded wire mesh of size of opening 12.5x12.5mm, and (33 X 16.5mm) expanded metal wire mesh of diamond size 33x16.5mm. Single layer, double layers and three layers of each type of the steel mesh were employed. All specimens were tested under 3-lines flexural loadings. The flexural performances of the all tested plates in terms of strength, stiffness, cracking behavior, ductility and energy absorption properties were investigated. The results showed that high serviceability and ultimate loads, crack resistance control, and good energy absorption properties could be achieved by using the developed ferrocement plates.

Optimal Robot Arm Movement using Tabu Search Algorithm

Abstract: This study presents an optimum approach to calculate the optimal robot arm movement for processing a considerable commitment of tasks using Tabu Search (TS) algorithm. In the scheduling problem, the objective is to minimize the total processing time related to tasks distances from each other. In the first step, the TS method is reviewed and we employ the proposed method in order to assign efficiently the optimal robot arm movement. In our proposed algorithm, the crossover rate is large at first and gradually it is decreased based on convergence improvement in next generations. We define an objective function including the operation times. Then, by minimizing this function using discrete TS algorithm, the optimal robot arm movement trajectory is assigned efficiently and quickly. If the resulted best cost converges to global minima, the crossover rate will be decreased in next generation. This method is studied in terms of operation time, convergence speed and quality of the results. Superior features of this algorithm are fast tuning, rapid convergence, less computational burden and capability to avoid from local minima. High promising results demonstrate that our proposed method is very efficient and can obtain higher quality solutions with better computational capability

Burden of rotavirus gastroenteritis in the Middle Eastern and North African pediatric population

<p>Abstract</p> <p>Background</p> <p>Rotavirus gastroenteritis (RVGE) is the most common cause of severe childhood diarrhea worldwide. Objectives were to estimate the burden of RVGE among children less than five years old in the Middle East (Bahrain, Iran, Iraq, Israel, Jordan, Kuwait, Oman, Qatar, Saudi Arabia, Syria, UAE, Yemen), North Africa (Algeria, Egypt, Libya, Morocco, Tunisia) and Turkey.</p> <p>Methods</p> <p>A comprehensive literature search was conducted in major databases on the epidemiology and burden of rotavirus among children less than five years old between 1999 and 2009. Data from each country was extracted and compared.</p> <p>Results</p> <p>The search identified 43 studies. RVGE was identified in 16-61% of all cases of acute gastroenteritis, with a peak in the winter. RVGE-related hospitalization rates ranged from 14% to 45%, compared to 14%-28% for non-RVGE. Annually, RVGE caused up to 112 fatalities per 100,000 in certain countries in the region. Hospitalization costs ranged from $1.8 to$4.6 million annually, depending on the country. The most recent literature available showed that G1P[8] was the most prevalent genotype combination in 8 countries (range 23%-56%). G2P[4] was most prevalent in 4 countries (26%-48%). G9P[8] and G4P[8] were also frequently detected.</p> <p>Conclusions</p> <p>RVGE is a common disease associated with significant morbidity, mortality, and economic burden. Given the variety and diverse rotavirus types in the region, use of a vaccine with broad and consistent serotype coverage would be important to help decrease the burden of RVGE in the Middle East and North Africa.</p