Kurdistan Journal of Applied Research (KJAR)
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Flexural Behavior of CFRP Laminate at Elevated Temperature
Get PDFA carbon fibre reinforced polymer (CFRP) laminate forms the surface part of an integrally heated tool. It was made up of carbon non-crimp triaxial fibre and SR8100 epoxy in accordance to the stacking sequence of [(0, ±45)/ (90, ±45)] S, using the resin infusion (RI) method. The laminate is heated up to 90ºC when the tool is operated; therefore under-standing the effect of temperature on the flexural properties is quite significant. This experimental study is carried out to investigate the flexural behaviour of the CFRP laminate and finding its flexural properties under the effect of elevated temperatures. For this purpose, various CFRP specim-ens were prepared and tested, using three point bending test method, at different temperature levels from room temperature to 90ºC. The results show that each of the flexural peak load, modulus and strength of the laminate decreases consistently with the increase of temperature. Also the laminate becomes slightly more flexible and significant loss occurs in its flexural modulus when the temperature elevates from 75ºC to 90ºC. The reduction in the flexural behaviour of CFRP is imputed to thermal softening of the epoxy polymer matrix whenever becomes closer to (HDT)
Multi-objective Optimization of Grid Computing for Performance, Energy and Cost
Get PDFIn this paper, new multi-objective optimization algorithm is proposed. It optimizes the execution time, the energy consumption and the cost of booked nodes in the grid architecture at the same time. The proposed algorithm selects the best frequencies depends on a new optimization function that optimized these three objectives, while giving equivalent trade-off for each one. Dynamic voltage and frequency scaling (DVFS) is used to reduce the energy consumption of the message passing parallel iterative method executed over grid. DVFS is also reduced the computing power of each processor executing the parallel applications. Therefore, the performance of these applications is decreased and so on the payed cost for the booking nodes is increased. However, the proposed multi-objective algorithm gives the minimum energy consumption and minimum cost with maximum performance at the same time. The proposed algorithm is evaluated on the SimGrid/SMPI simulator while running the parallel iterative Jacobi method. The experiments show that it reduces on average the energy consumption by up to 19.7 %, while limiting the performance and cost degradations to 3.2 % and 5.2 % respectively
Architectural Exploration of Blind CFO Estimation in OFDM Systems for Prototyping on a Reconfigurable Platform
Get PDFThis paper presents two architectures for prototyping an advanced carrier frequency offset (CFO) estimation technique for OFDM systems on field programmable gate array (FPGA). The parallel stream architecture (PSA) exploits the FPGA parallelism while the multiplexed stream architecture (MSA) employs multiplexing for more efficient hardware implementation. The dual-mode of operation for the proposed architectures has been proposed to achieve optimum performance depending on channel conditions. The proposed architectures with different implementation alternatives have been simulated and verified for FPGA implementation using the Xilinx’s DSP design flow. The estimation accuracy and the resource utilization for the proposed architectures have been evaluated. The prototyping results showed that MSA allows for more resource efficient implementation, where a single FFT core can be shared between parallel streams compared with PSA
Designing a Smart Traffic Light Algorithm (HMS) Based on Modified Round Robin Algorithm
Get PDFNowadays, traffic light system is very important to avoid car crashes and arrange traffic load. In the Sulaimani City / Iraq, there are many traffic problems such as traffic congestion or traffic jam and the amount of time provided manually to the traffic light system. This is the main difficulty that we try to solve. The traffic lights exist but still do not manage traffic congestion due to the fixed time provided for each lane regardless of their different load. Therefore, we are proposing to change the traditional traffic system to smart traffic system (adaptive system). This paper Focuses on the existing system (fixed system), then propose the adaptive one. The main crucial side effects of the existing system are:
Emergency cases: congested traffics might block the way of emergencies for instance ambulance, which transports people to the hospital
Wasting time of people generally and specially
Delays, which lead people to not to be punctual, this means people arrive late to the work
Wasting more fuels as staying more in the traffics, which affects the environment by increasing pollution
Vaginal Birth After Previous Caesarean Section
Get PDFThe proportion of women who attempt vaginal birth after prior cesarean delivery has decreased mainly because of the concern about safety. The purpose of this study is to observe maternal & neonatal outcomes in women delivered either by vaginal birth after caesarean section, elective repeat caesarean section or failed trial of labour. To design a definite protocol for selection of patient to achieve successful vaginal birth after caesarean (VBAC) section. A prospective observational study was set at Sulaimani Maternity Teaching Hospital/ Kurdistan region of Iraq, from first July 2013 to first July 2014. In which 200 pregnant women (with one prior caesarean section & singleton, term, cephalic presentation) were enrolled, followed up during labour & puerperium for maternal & neonatal complications. Data analysis was performed using the statistical software namely (SPSS version 20). Planned vaginal birth was successful in 63.4% of pregnant women, with the least maternal and neonatal complication, apart from 3rd degree perineal tear (2.3%) which was statistically significant (probability value < 0.001). In conclusion, the women who had successful vaginal birth after caesarean, had better result for the mother and neonate than failed trial of labour and those who had elective repeat caesarean section. Women with body mass index of < 30kg/m2, age <30 years, inter pregnancy interval >18months, non-recurrent cause of previous scar and estimated fetal weight of < 4kg, had more successful VBAC rate
THE PREVALENCE OF PRESBYOPIA IN OPTOMETRY CLINIC FOR ONE YEAR
Get PDFPresbyopia is a natural part of the aging process of the eye in which the loss of flexibility of the crystalline lens takes place over a number of years. This study aimed to determine the prevalence of presbyopia for all cases in the clinic of optometry in Erbil Technical Medical Institute for one year. During the study period optometric and ophthalmologic examinations were performed on all participants. Near vision was tested and corrected to the nearest 0.5 diopters. Presbyopia was defined as at least 1 line of improvement on a near visual acuity chart with an addition of a plus lens. presbyopic correction coverage was calculated and the results were analyzed using SPSS Program. A total of 750 participants' records were evaluated. Of those, 450 cases were females and 300 cases were males. Two hundred-twenty –five (30 %) of patients were presbyopia. Fifty-one patients of presbyopic patients (22.66%) were with ages between 39-45 year, seventy-five patients (33.33%) were with ages between 46-50 year, forty patients (17.77%) were with ages between 51-55 year, seventeen patients (7.55%) were with ages between 56-60, thirteen patients (5.77%) were with ages between 61-65 year, twenty patients (8.88%) were with ages between 66-70 year, six patients (2.66%) were with ages between 71-76 year, three patients (1.33%) were with ages between 76-80 year. Our study is the first population-based investigation of presbyopia in Erbil Clinics, with the aim of determining the prevalence of presbyopia in the clinic of Optometry that it is a sample of Kurdistan Region population. The results of this study indicate that the presbyopia was a common problem of the vision in Erbil
Estimation of vitamin C human protective dose for acetaminophen toxicity, using acute animal toxicity study
Get PDFAcetaminophen (APAP) is the main cause of fulminant hepatic failure. Vitamin C is a natural antioxidant with protective potentials against APAP toxic damage. In this animal study, and after an LD50 determination and selection of suitable lethal dose, the investigation was done to select a proper protective dose of vitamin C against lethal APAP dose. All 6 animal groups received a lethal dose of APAP (3250 mg/kg), group II, III and IV received 500, 1000 and 1500 mg/kg vitamin C respectively, group V received 1200 mg/kg N-Acetylcysteine (NAC), and group VI receive 1000 mg/kg vitamin C and 1200 mg/kg NAC. Mortality was recorded and liver histopathology was carried out. The results showed, the mortality rate in the group I was 68.75% and 37.5%, 31.25% in group II and III respectively, while group IV Showed a higher mortality rate and in group V and VI it was 25%. There was also a gradual reduction in the grade of histopathological damage in all groups, ranging from 2.4 ± 0.55 in group I to 0.4 ± 0.55 in group V and VI. In conclusion, vitamin C showed an increasing reduction in mortality and more histopathological protection, and it was more significant at 1000 mg/kg. NAC adds no more protection or reduction in mortality. The estimated protective dose of vitamin C was 700 to1127 mg for each gram of APAP. Incorporation of this dose of vitamin C with APAP preparations may be considered as a promising method for reducing mortality or severity of APAP intoxication
Computing Robin Problem on Unbounded Simply Connected Domain via an Integral Equation with the Generalized Neumann Kernel
Get PDFA Robin problem is a mixed problem with a linear combination of Dirichlet and Neumann D-N conditions. The aim of this paper are presents a new boundary integral equation BIE method for the solution of unbounded Robin boundary value problem BVP in the simply connected domain. The method show how to reformulate the Robin boundary value problem BVP as Riemann-Hilbert problem RHP which lead to the system of integral equation, and the related differential equations are also created that give rise to unique solutions. Numerical results on several tests regions by the Nyström method NM with the trapezoidal rule TR are presented to clarify the solution technique for the Robin problem when the boundaries are sufficiently smooth
Sensor Activity Scheduling Protocol for Lifetime prolongation in Wireless Sensor Networks
Get PDFIn Wireless Sensor Network (WSN), the dense sensor nodes deployment in the sensing field can be exploited in conserving the energy of the whole network, where the data of these nodes can be highly correlated. Therefore, it is necessary to turn off the unnecessary nodes that sense similar sensor readings so as to reduce the redundant sensed readings and decrease the communication overhead thus extend the WSN lifetime. This article suggests a Sensor Activity Scheduling (SAS) protocol for lifetime improvement of WSNs. SAS works in a periodic way. It exploits the spatial correlation among sensed sensor data in order to produce the best sensor activities schedule in WSNs. SAS composed of three phases: data collection, decision-based optimization, and sensing. SAS measures the similarity degree among the sensed data that collected in the first phase. It makes a decision of which sensors stay active during the sensing phase in each period and put the other nodes into low power sleep whilst keeping a good accuracy level to the received data at the sink to conserve the power and enhance the lifetime of the WSN. Several experiments based on real sensed data and by using OMNeT++ simulator demonstrate that SAS can save energy and extend the WSN lifetime efficiently compared with the other methods
Grouping vehicles in Vehicular Social Networks
Get PDFAs vehicles have become intelligent objects, creating social friendships among them is justifiable. Internet of Vehicles (IoVs) and Vehicular Ad-hoc NETworks (VANETs) are associated terms that are recently highlighted to improve the transportation systems. Intelligent vehicles that can communicate with each other are the main component of vehicular networks (VNs). Indeed, they have resources for that intelligence: CPU, transceiver, sensors and memory. On the other side, social networks (SNs) are also brought to light to mainly study the human relationships. In this context, gathering these vehicles in social groups is reasonable to share their information by bridging VN and SN in a multidisciplinary research direction called vehicular social networks (VSNs).This paper will present a model to group vehicles in two types of social groups. Casual groups and permanent or formal groups will be discussed to increase social ties among vehicles that have the same interests. The results will be analyzed to clarify the most important factors that affect such these relationships