Hassan L.H.,Duhok University |
Moghavvemi M.,University of Malaya |
Almurib H.A.F.,University of Nottingham Malaysia Campus |
Muttaqi K.M.,University of Wollongong |
Ganapathy V.G.,University of Malaya
International Journal of Electrical Power and Energy Systems | Year: 2014
This paper describes a method to determine the optimal location and the number of multi-machine power system stabilizers (PSSs) using participation factor (PF) and genetic algorithm (GA). The PF method is primarily used for number estimation and to identify the location of the PSSs, while the GA is applied to further reduce the number of PSSs, resulting in the optimization of their parameters and locations under different operating conditions. The problem is presented as a multi-objective optimization problem; maximizing the damping ratio of the electromechanical modes using different numbers of PSSs. The approach is successfully tested on the New England-New York interconnected system (16-machine and 68-bus), and its effectiveness in damping of local and inter-area modes of oscillations was proven. It is also compared to two other methods, which use only GA, in terms of damping ratio and computation time. In addition, the proposed approach demonstrates better performance compared to a fuzzy-based PSS when applied to the Iraqi National Super Grid System (INSGS). © 2013 Elsevier Ltd. All rights reserved.
Al-Timimi D.J.,Duhok University |
Ali A.F.,Azadi Teaching Hospital
Journal of Clinical and Diagnostic Research | Year: 2013
Introduction: There is increasing evidence on association between vitamin D insufficiency and diabetes, but the impact of vitamin D status on glycaemic status and vice versa, has not been well reported. Our aim was to investigate the level of 25-hydroxyvitamin D(25(OH)D) and the prevalence of vitamin D abnormalities in patients with diabetes mellitus (DM) type2 and in those without diabetes; and to ascertain the impact of 25(OH)D levels on glycaemic control and vice versa. Material and Methods: Serum 25(OH) D was determined in 337 Kurd patients with DM type2 and in 146 patients without DM type2. Its correlation with the marker of glycaemic control (HbA1c) as well as with anthropometric parameters (age, gender, and body mass index), diabetes duration, and serum blood glucose was examined. Discussion: The mean ± SD values for serum 25hydroxy (OH) D levels of diabetic patients was 25.6± 12.6 ng/ml and those for the controls was 34.1±14.7 ng/ml (p<0.01). The prevalence of vitamin D insufficiency was significantly higher among diabetic patients than among the controls(53.7% vs. 29.4%, p<0.001). This finding was still true even after the means of serum 25 (OH) D levels were adjusted to those of severe vitamin D deficiency (4.4% vs. 0.68%).Patients with poor glycaemic control had a higher prevalence of low vitamin D status (90%) than those with sufficient vitamin D levels (76%). As compared to diabetics with a good and fair glycaemic control, diabetics with a poor glycaemic control exhibited lower 25(OH)D levels (p<0.01) and a higher prevalence of low vitamin D status (89% vs. 4% and 7%) respectively. Patients with a diabetes duration of more than 5 years also had a higher prevalence of low vitamin D status as compared to vitamin D sufficient group (51% vs. 40%). A statistically negative significant correlation between serum 25 (OH) D levels and HbA1c % was found in diabetic patients (r=0.238, p<0.01). Conclusion: A low vitamin D status is present in two thirds of patients with DM type 2, particularly among diabetics with poor glycaemic control and among those with longer diabetes durations. This may reflect the additive effect of glycaemic control on vitamin D status.
Eesa A.S.,University of Zakho |
Orman Z.,Istanbul University |
Brifcani A.M.A.,Duhok University
Expert Systems with Applications | Year: 2015
This paper presents a new feature-selection approach based on the cuttlefish optimization algorithm which is used for intrusion detection systems (IDSs). Because IDSs deal with a large amount of data, one of the crucial tasks of IDSs is to keep the best quality of features that represent the whole data and remove the redundant and irrelevant features. The proposed model uses the cuttlefish algorithm (CFA) as a search strategy to ascertain the optimal subset of features and the decision tree (DT) classifier as a judgement on the selected features that are produced by the CFA. The KDD Cup 99 dataset is used to evaluate the proposed model. The results show that the feature subset obtained by using CFA gives a higher detection rate and accuracy rate with a lower false alarm rate, when compared with the obtained results using all features. © 2014 Elsevier Ltd.
Musa I.A.,Duhok University
Structural Engineering and Mechanics | Year: 2016
Consistent finite strain Plate constitutive relations are derived based on a hyperelastic formulation for an isotropic material. Plate equilibrium equations under finite strain are derived following a static kinematic approach. Three Euler angles and four shear angles, based on Timoshenko beam theory, represent the kinematics of the deformations in the plate cross section. The Green deformation tensor has been expressed in term of a deformation tensor associated with the deformation and stretches of an embedded plate element. Buckling formulation includes the in-plane axial deformation prior to buckling and transverse as well as in-plane shear deformations. Numerical results for a simply supported thick plate under uni-axial compression force are presented. Copyright © 2016 Techno-Press, Ltd.
Mizzouri N.S.,University of Malaya |
Mizzouri N.S.,Duhok University |
Shaaban M.G.,University of Malaya
Journal of Hazardous Materials | Year: 2013
This study analyzes the effects of toxic, hydraulic, and organic shocks on the performance of a lab-scale sequencing batch reactor (SBR) with a capacity of 5. L. Petroleum refinery wastewater (PRWW) was treated with an organic loading rate (OLR) of approximately 0.3. kg chemical oxygen demand (COD)/kg MLSS. d at 12.8. h hydraulic retention time (HRT). A considerable variation in the COD was observed for organic, toxic, hydraulic, and combined shocks, and the worst values observed were 68.9, 77.1, 70.2, and 57.8%, respectively. Improved control of toxic shock loads of 10 and 20. mg/L of chromium (VI) was identified. The system was adversely affected by the organic shock when a shock load thrice the normal value was used, and this behavior was repeated when the hydraulic shock was 4.8. h HRT. The empirical recovery period was greater than the theoretical period because of the inhibitory effects of phenols, sulfides, high oil, and grease in the PRWW. The system recovery rates from the shocks were in the following order: toxic, organic, hydraulic, and combined shocks. System failure occurred when the combined shocks of organic and hydraulic were applied. The system was resumed by replacing the PRWW with glucose, and the OLR was reduced to half its initial value. © 2013 Elsevier B.V.
Asker H.K.,Duhok University
ARPN Journal of Engineering and Applied Sciences | Year: 2012
One of the main goals during load calculations and vibration analysis for gears is the determination of deformation and stress state in teeth contact zones. This paper describes development of the finite element model for simultaneously monitoring the deformation and stress state of teeth flanks and teeth fillets for spur gears during the contact load period. The paper also describes the Finite Element Method simulation of contact conditions for spur gears teeth with complete 3 dimension meshing model. A suitable analysis is performed in order to select a meshed gears model which is sufficiently economic and in same time sufficiently geometrically accurate. The special algorithm for the tooth profile drawing is developed and built in currently available software (Ansys 10) for Finite Element Analysis to assure drawing of real flanks contact geometry. The optimal mesh size level is chosen, too. The described finite element models are made for the spur gear teeth during the dynamic loading state. The obtained numerical results are suitable for tracking deformation and stress hesitation with time and investigating the effect of damping coefficient on the obtained results. © 2006-2012 Asian Research Publishing Network (ARPN).
Ibrahim H.H.,Duhok University
European Surgery - Acta Chirurgica Austriaca | Year: 2016
Summary: Background: Hepatic hydatid cystic disease continues to be a serious health problem and is endemic in Iraq. There are of two types of cysts: noncomplicated and complicated cysts. Open surgery is widely practiced for both types. The aim of this study was to evaluate the clinical features, management, and outcome of surgical treatment in both types of cyst. Summary: Methods: The study included 150 patients operated on between 1996 and 2014. The patients’ demographic data, location, number, size, type of cysts, surgical procedure performed, morbidity, recurrences, and duration of hospital stay were recorded. Summary: Results: There were 102 female and 48 male patients with an age range of 4–70 years. There were more patients with noncomplicated cysts than complicated cysts – 94 and 56 patients, respectively. The complicated disease group had significantly more pronounced clinical presentations (p < 0.001) and higher postoperative morbidity (p < 0.001), and without significant change in recurrence rate (p = 0.059). Mean postoperative hospitalization time for noncomplicated cysts was 3.2 days, and for complicated cysts 5.6 days (p < 0.001). Summary: Conclusion: The most common type of hydatid cyst is the noncomplicated type, which has lower complication rates and shorter hospital stay regardless of the management technique of the cyst cavity. Therefore, complicated and noncomplicated cysts should be considered as different forms of the disease entity with different outcomes. © 2016 Springer-Verlag Wien
Hamamy H.A.,University of Geneva |
Al-Allawi N.A.S.,Duhok University
Journal of Community Genetics | Year: 2013
Haemoglobinopathies including the thalassemias and sickle cell disease are known to be prevalent inherited disorders in most Arab countries with varying prevalence rates and molecular characterisation. β-thalassemia is encountered in polymorphic frequencies in almost all Arab countries with carrier rates of 1-11 % and a varying number of mutations. The most widespread mutation in Lebanon, Egypt, Syria, Jordan, Tunisia and Algeria is the IVS-I-110 (G>A). In the Eastern Arabian Peninsula, the Asian Indian mutations (IVS-I-5 (G>C), codons 8/9 (+G) and IVS-I (-25 bp del)) are more common. The α-thalassemias are encountered in the majority of Arab countries in frequencies ranging from 1 to 58 % with the highest frequencies reported from Gulf countries. The (-α3.7) mutation is the most frequent followed by the non-deletional α2 polyadenylation signal mutation (AATAAA>AATAAG) and the α2 IVS1 5-bp deletion. The rates of sickle cell trait in Arab countries range from 0.3 to 30 %, with the Benin, the Arab-Indian and the Bantu haplotypes constituting the bulk of the haplotypes, leading to two major phenotypes; a mild one associated with the Arab-Indian and a severe one with the Benin and Bantu haplotypes. Public health approaches targeting prevention of haemoglobinopathies in Arab countries include newborn screening for sickle cell disease, and premarital screening for carriers of β-thalassemia and sickle cell disease. These services are still patchy and inadequate in many Arab countries recommending the upgrade of these services with strengthening of the education and training of health care providers and raising public awareness on the feasibility of prevention and care for haemoglobinopathies. © 2012 Springer-Verlag Berlin Heidelberg.
Mohammad A.M.,Duhok University
BMC cardiovascular disorders | Year: 2014
BACKGROUND: Cardiac complications are among the most serious problems of thalassemia intermedia patients. The current study was initiated to address the latter issue through the study of the echocardiographic findings and correlate it with clinical characteristics of thalassemia intermedia patients in Duhok, Kurdistan region, Iraq.METHODS: An echocardiographic assessment of 61 beta-thalassemia intermedia cases was performed. It included 30 males and 31 females, with a mean age 19.6 ± 7.5 years. The standard echostudy of two-dimension and M-mode measurements of cardiac chambers were done. The continuous doppler regurgitant jet of tricuspid and pulmonary valves were recorded. Left ventricle diastolic function was assessed by pulsed doppler of mitral valve inflow. To correlate the clinical with echocardiographic findings, patients were divided, according to tricuspid regurgitant velocity, into three groups (<2.5 m/sec, 2.5-2.9 m/sec and ≥3 m/sec).RESULTS: Tricuspid regurgitant velocity <2.5 m/sec, 2.5-2.9 m/sec and ≥3 m/sec occurred in 42(69%), 11(18%) and 8(13%) respectively. Comparing to other groups patients with tricuspid regurgitant velocity ≥3 m/sec were older and included more males. They had lower hemoglobin levels, but higher ferritin levels. Their age at diagnosis and the age of the initiation of blood transfusion were later. Most of them had significant exertional dyspnea. They also had relatively lower left ventricle ejection fraction values. Right ventricular diameter and right atrial size were larger in the same group. Tricuspid regurgitant velocity as a continuous predictor was associated positively with age, cardiac volumes and pulmonary regurgitation though negatively associated with ejection fraction.CONCLUSIONS: Echo-derived right and left side cardiac complications are not uncommon in thalassemia intermedia patients. Therapeutic trails targeting these complications are indicated, and echocardiographic assessment is necessary to be offered early for thalassemia intermedia.
Tahir A.A.,Duhok University
IEEE Transactions on Geoscience and Remote Sensing | Year: 2011
An approach for continuous daytime cloud classification system through satellite images is presented. The system is based on spectral ratio values as input features and a modified version of probabilistic neural network (PNN), named Quick PNN (QPNN), as a classifier. The use of spectral ratio values makes the system more efficient in detecting the minor changes in cloud spectral properties, leading to better classification capability. The modification to PNN consists of shrinking the hidden layer which is accomplished by performing K-means clustering on the training data of each class separately. Thus, for each class, instead of presenting all the training data samples in the hidden layer nodes, only the means of the resultant clusters are presented. The training data and the class labels are derived through the generation and interpretation of ratio images. The application of the approach to Meteosat-8 images has shown the separation of eight classes, including low clouds, middle clouds, high clouds, areas of high water vapor, sea surface, and land. The average accuracy of the system is 87.15% with a range of 84%-91% for the cloud and area of high water vapor classes, 93% for sea surface class, and 85% for land surface class. The computation time of the classification mode, including image ratioing and QPNN operations, is less than 1 min, which is good for continuous cloud classification and monitoring. The approach can be adapted to any multichannel satellite sensor only by using proper combination of ratio images. © 2011 IEEE.