Polytechnic Journal 2020-12-30T00:00:00-07:00 Dr. Hoshyar Amin Ahmed Open Journal Systems <p>Polytechnic Journal (Polytechnic J.) is a biannual scientific journal published by Erbil Polytechnic University, Erbil, KRG, Iraq. Polytechnic J. publishes original researches in all area of Pure Science, Applied Science, Technology and Engineering. Polytechnic J. is a Peer-Reviewed Open Access journal with Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (CC BY-NC-ND 4.0). Polytechnic J. provides immediate, worldwide, barrier-free access to the full text of research articles without requiring a subscription to the journal. Polytechnic J. is available online on OJS-PKP platform since January 2019.</p> <p>p-ISSN: <a href="">2313-5727</a> | e-ISSN: <a href="">2707-7799</a> DOI: <a style="color: #009de5;" href="">10.25156/ptj</a><br />____________________________________________________________________________________________________________________________</p> Numerical Study to Evaluate the Performance of Nonuniform Stepped Spillway Using ANSYS-CFX 2020-05-10T10:13:22-07:00 Shawnm M. Saleh Sarhang M. Husain <p>The main features that attract hydraulic engineers for designing stepped spillways are their ability to lose a large portion of the flow energy and add or increase aeration to the flow naturally. Hence, smaller size stilling basin and no aeration device may require. This study aims to find the amount of energy dissipation rate and the location of inception point over non-uniform stepped spillway. The numerical 2D ANSYS-CFX code is applied to generate and run thirty-two models of different configurations using two different moderate slopes (1 V:2 H and 1 V:2.5 H) as most of the downstream slopes designed for moderate slope, and two different step heights (h<sub>s</sub>= 0.08 m and h<sub>s</sub>= 0.016 m) under skimming flow discharge for different (d<sub>c</sub>/h<sub>s</sub>) ranging from d<sub>c</sub>/h<sub>s</sub>= 1–2.2, in which dc is the critical flow deptho n the crest. The volume of fluid is implemented and the renormalized group of k-ɛ turbulence model is activated. The computational results demonstrated that the amount of energy dissipation increases with decreasing the flow discharge, chute slope, and step height. In addition, it is observed that the length of the inception point is directly proportional to the discharge and inversely proportional to both the chute slopes and step height. Moreover, for the design point of view, the results revealed that configuration B can be considered as the optimal one amongst the others examined herein.</p> 2020-12-30T00:00:00-07:00 Copyright (c) 2020 Shawnm M. Saleh, Sarhang M. Husain Simulation of Mosul Dam Break Using Finite Volume Method 2020-03-30T09:32:17-07:00 Ayhan H. Saleem Jowhar R. Mohammad <p>Mosul dam is an earth-fill embankment located north of Iraq on the Tigris River forming a reservoir with 11.11 km<sup>3</sup> water storage capacity which is the largest dam in the country. The dam is built on a rock bed foundation, in which the dissolution process is dynamic in the zone where gypsum and anhydrite layers present. During the construction development seepage locations were found in the dam foundation and the grouting process is in progress until now to control this problem. Therefore, the possibility of the Mosul dam break is highlighted by previous studies. In this research, a FORTRAN code based on the finite volume method is modified to solve the two-dimensional shallow water equations and simulating the Mosul dam break. The computational domain discretized using unstructured triangular mesh. The solver applied Harten lax van leer with contact (HLLC) wave approximate Riemann solver to calculate the cell interface fluxes, and the semi-implicit scheme employed to solve the friction source term. The numerical scheme applied to two benchmark test cases, and the results showed that the presented model was robust and accurate especially in handling wet/dry beds, mixed flow regimes, discontinuities, negative water depths, and complex topography. The results of this study demonstrate that flood waves may reach the center of Mosul city in &lt; 6 h and water depth may rise to 34 m after 7 h of Mosul dam breaking. Finally, the simulation results of the Mosul dam break were used to prepare an emergency action plan.</p> 2020-12-30T00:00:00-07:00 Copyright (c) 2020 Ayhan H. Saleem, Jowhar R. Mohammad Effect of Straw Throwing Method and Some Operational Parameters on the Performance of a Small Rectangular Baler 2020-07-21T19:59:05-07:00 Affan O. Hussein <p>The experiment was carried out on a private farm in Karak village in 2017 to study the effects of the method of throwing the straw behind the combine harvester and some operational factors on the performance of a small rectangular baler. The field was planted with wheat (<em>Triticum</em> spp.) and barley (<em>Hordeum vulgare</em>). A small rectangular baler type (Ćicoria 454), Italian made was used to pick up and bale the straws, which were thrown as heaps and windrows in the field. The results obtained showed that picking up the straw as windrows improved the baler’s performance over the heaps in terms of number of mechanical units stops, time require for baling, fuel consumption, baler’s throughput capacity, and baler’s throughput efficiency, on the other hand, the forward speed also affected the baler’s performance when the straw was thrown as windrows; By increasing the forward speed, the slippage percentage increased but the fuel consumption, baler’s throughput efficiency, and baler’s throughput capacity decreased.</p> 2020-12-30T00:00:00-07:00 Copyright (c) 2020 Affan O. Hussein Prevalence of Needlestick Injuries among Healthcare Workers in Rizgary Teaching Hospital 2020-05-20T09:22:20-07:00 Salah H. Ali Peshtewan T. Majeed Umed A. Huwiezy <p>Needlestick injury in healthcare settings is a global issue. Despite being recognized for many years, needlestick and sharps injuries (NSIs) continue to present a risk of occupational exposure to blood-borne pathogens for health care works (HCWs). The objectives of the study were to determine the prevalence of needlestick injuries among HCWs in Rizgary Teaching Hospital and to identify the causes of needlestick injuries. A cross-sectional study was conducted on 76 healthcare workers in Rizgary Teaching hospital; there were a total of 45 males, 31 females. The data collections were administrated using face-to-face interviews to ensure a good response rate and to ensure all questions were answered. Most (52.6%) needlestick injuries occurred in wards with syringe needles being the most common causative tool; surgery ward was the most prevalent site of needlestick injuries occurrence (42.1%). The percentage of acupuncture was high and needles were the most common cause, and most injuries occurred during the re-use of the needles. The study recommends several measures to prevent and reduce acute injuries among HCWs; these measures include health education, behavior change, safer devices, and an educational program to educate these HCWs.</p> 2020-12-30T00:00:00-07:00 Copyright (c) 2020 Salah H. Ali, Peshtewan T. Majeed, Umed A. Huwiezy Evaluation of Bond Strength and Dimensional Accuracy of Soft Liner to Microwave Cured Denture Base Material 2020-05-19T08:13:29-07:00 Shilan H. Fatah Radhwan H. Hasan <p>Today, soft liners are being widely used in dental practices by their application to the inner surfaces of the denture with hopes to evenly distribute any potential uneven forces, and to provide a cushion effect to the oral mucosa of the patient mouth. The aim of this study is to investigate the influence of (a) polymethylmethacrylate (PMMA) denture base material curing technique, (b) Molloplast B soft liner curing technique, and (c) PMMA surface treatment, on the “shear bond strength” (SBS) between the Molloplast B liner and PMMA. A total of 80 samples were used in this study to evaluate the SBS performance of microwave (Nature-Cryl, Acron Gc, Japan) and conventional water bath (Ivoclar triplex, Liechtenstein) curing techniques of PMMA, and to evaluate the curing technique of soft liner material Molloplast B (DETAX,GERMANY). Surface treatment of PMMA was performed for half of the samples using neodymium:yttrium aluminum-garnet Nd:YAG laser, and the other half of the samples were surface-treated using AL<sub>2</sub>O<sub>3</sub> sandblasting method. The results showed that the highest mean value in conventional water bath-cured soft liner was 26.69 MPa, whereas the lowest mean value for microwave-cured soft liner was 15.22 MPa. No significant difference was observed between the SBS performance regarding the PMMA surface treatment and curing techniques. Conventional water bath curing technique for soft liner treatment improved the SBS performance. Regarding the PMMA curing technique, the conventional water bath achieved higher SBS, yet the difference was not statistically significant. Finally, surface treatment using laser improved the SBS compared to sandblasted method, but the improvement here was also statistically insignificant.</p> 2020-12-30T00:00:00-07:00 Copyright (c) 2020 Shilan H. Fatah, Radhwan H. Hasan Determination of Potential Runoff Coefficient using Geographic Information System for a Small Basin in Balakayety Watershade, Kurdistan Region of Iraq 2020-02-08T16:50:05-07:00 Jehan M. Fattah Sheikh Suleimany <p>Runoff coefficient is an index for losses in rainfall required in most hydrological models and water resources projects. Generally, in the Balakayety water shade in Kurdistan region of Iraq, no runoff data are available as almost basins are ungagged. The Geographic Information System (GIS) techniques and available data for a small basin in Balakayety watershed within the Erbil governorate (Kurdistan Region of Iraq) were used to estimate the coefficient of potential runoff coefficient (PRC). The estimated PRC will be then used to calculate the depth of runoff. The Satellite Imagery (Landsat 7 ETM+) for 2015 was procured to create land cover classes, the classifications accuracy equal to 88.4%, and the Kappa index is 83.7%. The slope map developed from the digital elevation model with 30 m resolution. The area’s hydrologic soil map is digitized from the Iraqi soil map. The inverse distance weighting method was used to interpolate the rainfall of the study area into the Arc GIS. It was found that the most study area covered by moderate to high (PRC) values ranged from 55% to 83%, and runoff depth values vary from 398.1 mm to 610.3 mm. The present study indicates that the integration of all obtained thematic maps into GIS provides a powerful tool for calculating the runoff coefficient for catchments lacks streamflow data which can result in flood/drought predictions that will be not accurate. These findings are helpful in identifying flood areas, selecting proper sites for water harvesting, and enhancing water resources management programs.</p> 2020-12-30T00:00:00-07:00 Copyright (c) 2020 Jehan M. Fattah Sheikh Suleimany Effects of Dam Gate Geometry on Pressure Variation Aided by Map Presentation 2020-05-20T08:47:24-07:00 Sheeraz M. Ameen Thamir M. Ahmed <p>The dam vertical lift gate is one of the most important operational parts that regulate the high head water flow to power plants as well as satisfying the water needs for projects and areas downstream of the dam. Due to the high water levels in the dam reservoir, the gates are subjected to many hydrostatic and dynamic pressures that affect their performance and stability. Hence, it became necessary to study all parameters that may cause excessive pressures which may lead to reduce the gate performance efficiency or even cause failure. In the current study, the pressure distribution along the bottom surface of various gate lip shapes has been measured and presented as contour maps using Surfer software. The pressure fluctuation was observed to indicate the intensity of flow separation and reattachment which, in turn, causes a vibration that may threaten the stability of the gate or impede its proper functioning. The pressures in this study are expressed as a dimensional coefficient through the integration of pressure measurements at 8 points distributed over the bottom gate surface. The high intensity of pressure attachment indicates the critical condition for hydraulic design.</p> 2020-12-30T00:00:00-07:00 Copyright (c) 2020 Sheeraz M. Ameen, Thamir M. Ahmed Biocompatibility of Styrene-butadiene Copolymer-modified Calcium Phosphate and Mineral Trioxide Aggregate 2020-05-19T07:25:10-07:00 Hala B. kaka Raid F. Salman <p>The biocompatibility of root canal filling material is one of the basic conditions for a successful endodontic treatment and healing of the periodontium. This study was aimed to evaluate the biocompatibility of calcium phosphate cement modified with the styrene-butadiene copolymer-modified calcium phosphate (mCPC) by its implantation in the subcutaneous tissue of rabbit. Fifteen female rabbits of comparable weight were used in this study, each one had received three different tubes; one containing mCPC, the other with mineral trioxide aggregate Fillapex, and an empty control tube on the subcutaneous tissue of thighs. After a definite time (3, 7, and 14 days), the tissues around the tubes were collected, fixed, and processed for histologic evaluation. A histopathological specialist measured the intensity of inflammation. Kruskal–Wallis test was used to analyze the data. The results showed a significant difference with mCPC group in different periods, there was a high intensity of inflammation at the beginning, then it fell, and sustained as mild inflammation. One can conclude that the new formulation of CPC considered biocompatible, which rises the success rate of endodontic treatment.</p> 2020-12-30T00:00:00-07:00 Copyright (c) 2020 Hala B. kaka, Raid F. Salman Association between Smartphone Addiction and Physical Activity, Sleeping Hours among Medical Science Students in Duhok City 2020-07-06T20:30:53-07:00 Rebar Y. Abdullah Kawther M. Galary Robar A. Majid <p><strong>Background and Aim</strong>: Smartphones become a part of today’s life. In spite of the convenience, it contributes to our daily lives and activities, one of the most important problems is smartphone addiction. As known, smartphone addiction is a type of technological addiction or non-substance addiction. The present study is to investigate the association between smartphone addiction and physical activity, sleeping hours among medical science students in Duhok City.<br /><strong>Subjects and Methods</strong>: A cross-sectional study design carried out with 295 students in medical science colleges in the Duhok City of both gender. Self-reported data collected from December 15, 2019, to January 22, 2020. Structured questionnaire has been used to gather data related to sociodemographic, physical activity, sleeping hours, and smartphone addiction.<br /><strong>Results</strong>: The study found most students, 78.3% have smartphone addiction, 78% of medical science students are at low physical activity range, and only 2% of students are at normal physical activity range, also revealed 20% of students were inactive. According to daily sleeping hours, more than half of them, 61.7% were in a healthy range of sleeping; however, no statistically significant association found between smartphone addiction with physical activity, sleeping hours while finding a highly statistically significant association between smartphone addiction with gender.<br /><strong>Conclusion</strong>: The current study figure out smartphone addiction prevalence was very high among medical science college students. Smartphone addiction showed an effect in increasing sedentary health behavior like low physical activity and poor sleeping quality with no statistically significant association.</p> 2020-12-30T00:00:00-07:00 Copyright (c) 2020 Rebar Y. Abdullah, Kawther M. Galary, Robar A. Majid Root Dentine Strain Generation during Root Canal Instrumentation with Rotation and Reciprocation Motions 2020-06-14T09:50:33-07:00 Bnar O. Hama faraj Raid F. Salman <p>The aim of the study is to measure and compare strain generated on root dentine surface by two different instrumentation motions. Thirty extracted single canal premolars were used in this study which randomly was divided into two groups, one group was prepared with ProTaper NEXT X2 file in rotation motion, and the second group was prepared by WaveOne GOLD primary file in reciprocation motion, the canals were irrigated during canal preparation by 2 ml of sodium hypochlorite and 17% EDTA gel was used. Strain measurement was performed by strain gauges and a digital strain output reader, data were recorded every 5 s for 50 s. The results of this study have shown that WaveOne GOLD had higher mean 0.7308±0.41106 than ProTaper next 0.5385±0.39904 which means WaveOne GOLD generates greater strain than ProTaper NEXT. However, according to Student’s t-test between two groups there is no statistical difference between them. Based on the results of this study, there was no difference between the two motions; both motions generated strain on root dentine surface.</p> 2020-12-30T00:00:00-07:00 Copyright (c) 2020 Bnar O. Hama faraj, Raid F. Salman Association of Lipid Profile with Body Mass Index in Public Employees in Halabja City, Kurdistan Region of Iraq 2020-06-14T09:53:28-07:00 Tareq H. Abdullah Hardi R. Baqi Salar H. Karim Dashti A. Ghafor <p>Obesity and overweight are extensive phenomena that reached epidemics extent worldwide, including the Kurdistan region of Iraq. The aim of this study is to evaluate the values of total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), body mass index (BMI), and the state of physical activity in Halabja’s public employees. Overall 355 adults aged from 19 to 63 including 246 males and 109 females contributed to the study. The lipid profiles were tested in all subjects after over-night fasting. In addition, anthropometry measurements were taken; the mean height for males is 1.7129 m and 1.5732 m for females. The mean weights of males and females are 80.4813 and 69.9459 kg, respectively. The mean BMI value for males and females is 27.4258 and 28.3274, respectively. Some of the cases were diagnosed with diabetes, renal diseases, hypertension, and other relevant diseases. 246 of participants adopted sedentary lifestyles while 109 of them lived an active lifestyle. 65, 162, 98, and 206 of participants had TC, TG, LDL-C, and HDL-C off-limits, respectively. Pearson’s correlation between BMI with TC, TG, and LDL-C showed a significant relationship at 0.01 level as 0.156**, 0.140**, and 0.144**, respectively. HDL-C was negatively correlated to BMI at −0.062 level. The analysis of variance showed statistically significant p-values between TC, TG, and HDL-C according to BMI at 0.027, 0.000, and 0.000, respectively. The sedentary group of participants showed a higher Mean range of TC, TG, LDL-C, and HDL-C than an active group of participants.</p> 2020-12-30T00:00:00-07:00 Copyright (c) 2020 Tareq H. Abdullah, Hardi R. Baqi, Salar H. Karim, Dashti A. Ghafor Prevalence and Distribution of Oral Conditions among Dental out Patients Children Aged 0–13 Years Attending Khanzad Polyclinic Center in Erbil City 2020-07-19T08:05:12-07:00 Banaz A. Abdullah Shaheen A. Ahmed Ali F. Mohammad Alzubaidee <p>Prevalence studies on oral conditions affecting children are rare worldwide, and none of them was conducted in in Erbil/Kurdistan region/Iraq. The aims in the this study were to determine the prevalence and distribution of oral conditions which include both lesions and normal variations in group of patients referred to a main, public specialized poly clinics dental center. A prospective cross-sectional study was performed, the including data collected were age, gender, and site of a condition. The examination of the patients was performed under standardized conditions; using artificial light, disposable gloves, retractors, and mirror with sterile gauze to hold tip of the tongue. Statistical analysis was performed using Statistical Package for the Social Sciences (SPSS) version 22; Fisher’s exact test; and Chi-square test. A sample of 520 children, aged range (0–13) years included in this study, 265 (51.0%) were males and 255 (49.0%) were females, divided into three age groups; 100 (19.2%) were &lt;5 years, 274 (52.7%) were 5–9 years, and 146 (28.1%) were 10–13 years. The prevalence of oral conditions was significantly higher in 5–9 years (52.7%). The most commonly clinically diagnosed oral conditions were fissure tongue (13.1%), followed by gingivitis (9.0%) and dentoalveolar sinus (8.3%). As a first study in this age group in Erbil/Kurdistan region/Iraq, oral conditions are relatively common in the sample examined; dentist and dental practitioner should be aware for their recognition and referral for management.</p> 2020-12-30T00:00:00-07:00 Copyright (c) 2020 Banaz A. Abdullah, Shaheen A. Ahmed, Ali F. Alzubaidee Bolton Ratio of Different Angle’s Classifications in a School Children Sample of Erbil City 2020-05-17T09:20:58-07:00 Amanj R. Ibrahim Zana Q. Omer Hasan S. Hasan Walaa M. Saleem Almola <p>Aims of this study were to determine both the Bolton anterior and overall ratios in a representative sample of Erbil schoolchildren of Normal occlusion and Cl I, Cl II div I, div II, and Cl III malocclusion, also to find if there are any gender differences. Numerical data were obtained, comprised of 320 samples study casts of students with a mean age of 13–15 years selected from different schools in Erbil City. The casts were divided into 5 groups according to the type of malocclusion: Normal (n = 64), Cl I (n = 64), Class II div I (n = 64), Class II div II (n = 64), and Class III subjects (n = 64). The measurement of the greatest mesiodistal width of the teeth was performed using digital Vernier directly on the study casts, from the distal surface of the left first molar to the distal surface of the right first molar. The overall and anterior ratios between the maxillary and mandibular teeth were computed and evaluated using Bolton’s method. The results revealed that the mean anterior ratio (78.863) was higher and statistically signifi cantly different from anterior Bolton’s (77.2) and also the mean overall ratio was not statistically signifi cant different from Bolton’s ratio (91.3) (P = 0.239), with respect to the overall and anterior ratios among all the groups, statistically significant differences were found. Differences between genders were analyzed using a t-test. The results showed that there were no signifi cant differences between males and females. There were non-significant differences between the findings of the present study and those of Bolton’s study for overall ratio and anterior ratio, but among all five classifications, there was a significant difference of Erbil population not similar to Bolton ratio and there was no significant difference between males and females.</p> 2020-12-30T00:00:00-07:00 Copyright (c) 2020 Amanj R. Ibrahim, Zana Q. Omer , Hasan S. Hasan, Walaa M. Saleem Almola