bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental and theoretical analysis of heat transfer in a solar collector storage
Authors: Al-Dayyeni Hadi R. , Khudhayer Wisam J. , Karatas Cihan , Kanbar Jaber Mustafa Wahby , Jalel Hasan T. 
Published: August 2021

Abstract
The current research includes a practical study of the thermal performance of solar collector integral storage system (ISCS) in which different types of heat exchangers are immersed in its enclosure for comparison. The first type is a straight tube heat exchanger (ST) and the other is a heat exchanger in the form of a coiled tube (CT). The effect of single and double glass layers and fluid flow rates inside the heat exchanger on the natural convection heat transfer of ISCS system is experimentally evaluated by determining the temperature difference of inlet and outlet water through the heat exchanger immersed into the ISCS enclosure, the temperature distribution inside the enclosure, the ISCS efficiency, and the amount of thermal storage during evening times. Three sets of experiments are performed for a different water flow rates (1.0, 1.5, 2.0, and 2.5 Lpm) inside the heat exchanger that is immersed in the thermally insulated enclosure and different glassing layers. The first set represents the presence of a heat exchanger in the form of a straight tube with a single glass was layer on the top face of the enclosure that is called (STSG). The second set uses a coiled tube heat exchanger with a single glass on the upper side of the enclosure and it’s named as (CTSG). The last set of experiments is represented by a heat exchanger in the form of a coiled tube with a double glass on the upper face of the enclosure and it’s abbreviated as (CTDG). At water flow rate of 1 Lpm, the CTDG exhibited higher temperature difference (28 °C and 19.9 °C than (19.4 and 11.4 °C) for CTSG and (12 and 7.3°C) for STSG during day and night times, respectively. The results reveal that the thermal efficiency (84.5 - 77.8 %) of the (CTDG) case at water flow rate of 2.5 Lpm was higher than the efficiency (68.8 - 56.6%) of (CTSG) case and that (41.7 - 39.7%) of STSG) case during day and night times, respectively. It was also observed that the internal energy exceeds the amount of solar radiation during the day and provides a thermal storage at night due to the complete isolation of the collector. The temperature measurements near the tube allow the calculation of the Rayleigh number during the heat transfer process, and empirical relationships haves been deduced for each set of experiments between the Nusselt number and the Rayleigh number.
Determination the Normalized Difference Vegetation Index (NDVI) for the NH-38-2 Al-Najaf Plateau, Iraq with the Assistance of the Remote Sensing Technology
Authors: Alkatib Aseel A 
Published: August 2021

Abstract
The satellites and the data that is provided by are an effective way to distinguish the characteristics of agricultural crops, crops density, and the changes that affect the vegetation cover. The Normalized Difference Vegetation Index (NDVI) has been widely used in conducting a quantitative assessment of plants that cover the surface of the earth, as it revealed many problems facing the agricultural environment, especially those located in arid or semi-arid areas. This study dealt with analyzing the vegetation cover of the plateau NH-38-2 located in Al-Najaf, Iraq by finding the NDVI using remote sensing technology and Geological Information System (GIS), in addition to finding its value for the study area. The study showed that the vegetation cover is largely non-existent and ranges between (0-1) as the region suffers from desertification, which requires the relevant authorities to rectify the matter by developing projects that will increase the vegetation cover as it helps to improve the environment. In addition, the study showed that there is an area that does not exceed 110 km2 that contains vegetation, which is a very small area compared to the total area under study, which is 15225 km2.
The Effect of α-Particles on Structural, optical and Morphological Properties for Cadmium Selenide Thin Film
Authors: Al Refaei D H , Al Taan L M , Najam L A 
Published: August 2021

Abstract
In this paper, the effect of alpha particles on cadmium selenide thin film properties was invistecated. (CdSe) thin films prepared on glass bases at 50°C and 70°C tempartures, and pH=9 using the chemical bath deposition method. The irradiation was performed on (CdSe) films use the alpha particles source Americium (Am-241) with activity of 50μCi and energy 5.3MeV for a period irradiation of 5 hours. The samples were characterized by using the XRD, FESEM and EDX techniques. The optical measurements have been obtained by using the UV-V spectrophotometer. The results showed that there are effects of alpha particles on the optical and structural properties of the films. It was found that the energy gap increases slightly after the CdSe thin film irradiated, the absorption coefficient (α) is increases with irradiation due to the increase in the energy gap. The structure of the CdSe films has been transformed slightly from the cube structure to the hexagonal structure. The grain size increases with irradiation where the relative density increases clearly. The shape of the CdSe thin film at 70°C is affected by irradiation more over than at 50°C.
Assessment of Multiaxial Fatigue Damage Criteria Based on the Critical Plane Concept in Micro-EHL Line Contact.
Authors: Al-Mayali M F , Albattat Ali , AL – Asadi Hassneen , Sharif K J 
Published: August 2021

Abstract
Micropitting is a fatigue failure phenomenon that concentrates at the surface roughness level between interacting surfaces. This type of surface fatigue is commonly recognized to exist in gears and bearings, where specific film thicknesses are sufficiently low that the rough surfaces run in the EHL condition, where the direct asperity contacts are prominent. This paper is an experimental and theoretical study to investigate a number of fatigue failure theories concerning the multi-axial fatigue models which are depended on a critical plane analysis in the mixed lubrication regime. These failure theories are namely the Findley, the Matake, the Dang Van, McDiarmid and, Fatemi and Socie model, where they are used to perform fatigue investigation for Micro- EHL contacts problem. Numerical analysis to investigate the cumulative damage and fatigue parameter in a Micro- EHL contact is established in this paper. The results of applying failure theories have indicated that the different multiaxial fatigue criteria adopted provide significant results for contact analysis in lubricated conditions, and they are more relevant to the applications of the rough surface Micro-EHL mode.
Design, modeling and FEA analysis of internal symmetric and asymmetric involute spur gears
Authors: Alarazah H A , Abdullah M Q 
Published: August 2021

Abstract
Recently, internal gears become widely used and highly required according to its ability to transmit large torque to weight ratio, high bending strength, smooth transmission, low noise, and low vibration. Therefore, internal gears are strongly recommended in particular “planetary gear transmission systems”. In this paper, internal involute spur gears are designed based on conventional approach of involute gears. Matlab is used to attain the points of internal gear and to get the main parameters of internal tooth profile, these points have been read by AutoCad to have two dimensional tooth profile. Finite element analysis using Ansys is achieved to analyze and compared the strength of three types of internal gears, Symmetric (20° - 20°) that has been chose to be the standard case, Asymmetric (14.5° - 35°) and Corrected Asymmetric (14.5° - 35°). Tetrahedral type patch conforming method with element size1mm have been chose for fine meshing. The internal gear is fixed supported from the outer ring then, 6500 N.m torque is applied at the rotating axis of the pinion. The bending stresses are calculated based on Von-Mises theory using (FEA). Finally, this study is presented to demonstrate the superiority of internal asymmetric tooth and improve and optimize this significant type of gears.
New Fabricated UHMWPEO-PVA Hybrid Nanocomposites Reinforced by GO Nanosheets: Structure and DC Electrical Behaviour
Authors: Aldulaimi Nisreen R. , Al-Bermany Ehssan 
Published: August 2021

Abstract
Polymer-graphene-based nanocomposites are promising to subject for engineering and industrial. This investigation focused on fabricated new nanocomposites from polyethylene oxide (UHMWPEO) with polyvinyl alcohol (PVA) with various loading ratios. In addition, the influence of graphene oxide nanosheets (GO) contribution was significant enhanced the electrical properties. Three different loading ratios of both polymers were applied with the addition of GO to synthesis new six samples using the solution-sonication-casting method as UHMWPEO: PVA: GO (87:12:1, 74.5:24.5:1, and 63:36:1 wt. %). Rang of characterizations was applied such as Fourier-transform infrared spectroscopy (FTIR) spectra that presented showed strong interfacial connections formed between the blended polymers in the matrix and GO nanosheets in the nanocomposites and the optical microscopy (OM) images exhibited fine homogeneity of the polymer matrix and excellent dispersal of the GO in the matrix of polymers. The DC electrical conductivity showed notable improvement of (PEO - PVA) blended polymer form (2.34663 * 10−17) (Ω.cm)−1 up to (3.00327*10−10) of nanocomposites. The findings are promising that could grow various applications such as sensors, solar cells, IR, electrical and microwave absorption panels.
Influence of waste glass powder and crushed cobblestone on mechanical properties of concrete
Authors: Al-Lebban Maher F. , Alhabbobi Alaa M. , Talib Ameer Gh. , Jabal Qusay A. 
Published: August 2021

Abstract
This research includes the study of the mechanical properties of normal concrete and concrete made of waste aggregates, such as stress-strain behavior and flexural strength. The waste aggregate contains fine waste glass powder and waste crushed boulders (cobblestone type) as coarse aggregate. The stress-strain behavior shows higher values of compressive strength and modulus of elasticity and larger area under stress-strain curve comparing with ordinary concrete which is containing ordinary aggregates. Also, the flexural strength is increased when using waste aggregates. The most benefit of this study is the cost decrease of concrete and clean environment by using waste materials in addition to higher values of compressive and flexural strengths. Total replacement of normal aggregate with waste aggregate gives the largest area under stress-strain curve. Compressive strength is increased from 36.4 MPa for control mix to 43.1 MPa for total replacement. The modulus of elasticity was about 30.6GPa for waste aggregate concrete of total replacement whereas in the normal aggregate concrete it was 26.4 GPa. In normal concrete, larger area under stress-strain diagram for waste aggregate concrete is achieved and that means higher toughness concrete. Also, high strength concrete is achieved by 75% and 100% replacement of normal aggregate with waste glass and cobblestone, respectively. The study includes the freezing-thawing cycles effect on concrete and the results show higher strength by using crushed glass and cobblestone aggregates. The aim of this study is to improve mechanical properties of concrete and durability of concrete to freezing and thawing by using waste glass aggregate and crushed cobblestone.
Studying the behavior of the concrete mixture with wheat straw as part of the cement
Authors: Al-Kadhim Hameed Mohammed Abd , Razzq Alzerjawi Ahlam K. , Mahdi Zaid Abdulzahra 
Published: August 2021

Abstract
This paper is an experimental study that was made on the effects of using Wheat Straw Ash (WSA) as a partial replacement of cement in the concrete mixture. The control specimens with ordinary portland cement (OPC) were made and in other specimens, cement was replaced with 10%, 15%, and 20% of WSA by weight of the cement. Wheat straw locally available was burned to ash in a controlled manner in the oven, which was used in this study. The destructive tests included the compressive strength, modulus of rupture, and splitting tensile strength were carried out on the concrete mixture using WSA at a different percentage of cement replacement and were and compared with control specimens. The tests result gained show that the compressive strength decreases when surrogating cement with WSA. While the modulus of rupture increase with 10 % WSA also, the splitting tensile strength increase with 15 % WSA.
A comparative analysis of BIM standards and guidelines between UK and USA
Authors: Ibrahim Mwafaq Yousif , Al-Kazzaz Dhuha Abdulgani 
Published: August 2021

Abstract
Architectural projects, carried out by the public sector in Iraq using traditional methods suffer from lots of problems such as the inaccurate estimation of time and cost, and the poor cooperation among project team members. To tackle these problems, it is important to benefit from the experiences of the pioneering countries in this field such as the UK and USA. These countries kept pace with digital development and established new systems in construction, namely Building Information Modelling (BIM). This paper investigates the similarities and differences between the BIM standards and guidelines in the UK and USA. The findings of this comparative analysis can build a knowledge base for establishing BIM standards in Iraq. The paper identified the similar aspects to be adopted in the Iraqi standard of BIM, such as the design techniques, the designers’ roles and responsibilities, and some aspects in the information management. In addition, their differences are distinguished, which indicate the specificity of BIM application in each country. For the different aspects, the Iraqi BIM standard can either adopt the descriptions of the UK or USA such as the method of structuring design data, or reflect the Iraqi specificity such as the national library of BIM.
Using of geographical information system and water quality index for evaluation of groundwater quality in the Dammam Zone, Faddak farm, Karbala, Iraq
Authors: Abed E H , Hassan W H , Faisal A AH 
Published: August 2021

Abstract
This study aims to evaluate the groundwater quality for irrigation purpose in the Dammam formation, Faddak farm, Karbala governorate. Set of physical and chemical parameters included the concentrations of cations and anions were measured in the water samples taken from seven wells in the region under consideration. Results have been analyzed with aid of geographical information system (GIS) by application of “Inverse Distance Weighted, IDW” interpolation method. The plotted maps proved that the groundwater in the study area can classify as “slightly brackish water” because the total dissolved salts ranged from 1000 to 300 mg/L. Also, the sulfate and chloride ions have relatively very high values with arrangement of cations of Na+ > Ca2+ > K+ > Mg2+ and anions of SO42- > Cl-> HCO3-> NO3-. The calculated values of Irrigation water quality index (IWQI) was greater than zero and less than 40; so, the water can identify as “severe restriction, SR”. Therefore, this water can’t be used for irrigation purpose and can be applied only for the soil with high hydraulic conductivity which popular property for study area.
Watershed basins delineation using GIS and Digital Elevation Model (DEM) to the region NI-38-14 Karbala-Al-Najaf Plateau, Iraq
Authors: Kareem Hayder H , Alkatib Aseel A , Mahdi Waseem H. 
Published: August 2021

Abstract
The available watersheds in the vast lands need extraction and determination in order to benefit from them and estimate the quantities of water supplied by these watersheds. The satellite image is uploaded to the NI-38-14 Karbala-Al-Najaf plateau from the USGU website in the form of a Digital Elevation Model (DEM). GIS technology is used to calculate the morphometric properties and output them in the form of tables and cartographic models. The water networks of the geographical plateau NI-38-14 located between the administrative borders of the provinces of Al-Najaf and Karbala in Iraq are devised by extracting a topographic map of the area and calculating the areas of the watersheds and their perimeters. The topographic map showed great variations in the level of the earth’s surface, as the heights of the area ranged between 20m and 120m. The number of watersheds extracted in the Karbala-Al-Najaf plateau is 150 watersheds with different areas, the large area is about 4882 km2, while the small area is about 1 km2, and between those areas there are various areas. The largest recorded watershed circumference reached 580km in area (4882 km2), while the lowest recorded perimeter is 8km for the area (1 km2).
Maximum surface settlement prediction in EPB TBM tunneling using soft computing techniques
Authors: Samadi H , Hassanpour J , Farrokh E 
Published: August 2021

Abstract
Earth pressure balance (EPB) TBMs are commonly used for soft ground tunneling in urban areas. In metro tunnels’ excavation, designing a comprehensive monitoring system to control surface settlement is essential to prevent damage to surface structures. The present study aims to develop new prediction models to estimate the ground surface settlement using two soft computing techniques, SVM and ANN-MLP, and a multiple variable regression model to develop the new empirical formulas. The TBM operational parameters collected from the Tehran metro line 6, South extension (TML6-SE) project have been applied to confirm the provided models. In the data analysis process, the relationships between various parameters (torque index, thrust index, and earth pressure) and the ground surface settlement are investigated. Moreover, several statistical evaluation criteria are implemented to evaluate the performance of the developed models. The results show that the predicted values are in good agreement with the real data. The results can be used for similar ground and TBM tunneling conditions.
FDM analysis of earth dams – end of construction and water seepage (case study: Ivshan Iran dam)
Authors: Ramsheh F A , Rashiddel A , Dias D 
Published: August 2021

Abstract
In this research, the Ivshan earth dam was modeled with the finite difference method (FDM) for staged construction and water seepage. A maximum settlement was 100 cm in the numerical model when construction was complete, and it occurred in the middle of the dam’s height. Also, the FDM results showed consistency with field observations of the deformation instrument (inclinometer). After the reservoir’s initial filling, the pore water pressure ratio changes were investigated for the dam’s central axis. The results of the numerical model show relative stability in terms of pore water pressure ratio. The arching ratio is also obtained in the dam’s central axis for both construction and initial filling. The lowest values of the arching ratio in the central axis of the core at the end of construction and initial filling are 0.81 and 0.80, respectively, which occurred at the height of about 41 meters and about two thirds of the height of the dam embankment. Finally, the Factor of Safety of the dam at the end of construction and initial dewatering was investigated, and the results showed the stability of the earth dam.
Utilising PET Bottle Fibers in the production of Concrete
Authors: Rasheed Laith Sh. , Alyhya Wajde S. , Kadhim Sawsan K. 
Published: August 2021

Abstract
This study attempts to apply the concept of sustainability by reducing the environmental pollution of plastic waste, especially Polyethylene Terephthalate (PET) that are used in production soft drinks bottles. The plastic bottles were collected, roughened) Roughen the surface by using a metal clip after exposing it to heat, and then place it on smooth surfaces) and shredded into fibres of specific size and shape with an aspect ratio (L/D) of 34.5. Various proportions of PET (i.e. 0.5, 1.0, and 1.5%) have been used in the production of ordinary concrete. The influence of PET fibers on the properties of concrete was studied, such as workability, compressive and splitting tensile strengths. Furthermore, the shear characteristics of continuous reinforced concrete deep beams with dimensions of (150×300×2000) mm produced from such concrete were also investigated. For all percentage of replacements, The fresh property, compressive strength, and tensile strength of PET fibre encapsulated cement concrete were investigated. With the addition of plastic fibre, compressive strength increased marginally, but tensile strength measurements showed a substantial improvement over the control specimen. it has been found that there was an apparent impact of waste plastic fibers on the structural behavior of the investigated beams in terms of its brittleness. The increase in the ultimate load capacity With the increase in the percentage of fiber until a percentage(1%), then it begins to decrease after this percentage of continuous deep beams refers to the use of waste plastic fibers to improve the tensile properties of concrete and to limit the spread and width of cracks within the structure.
Repairing of one-way reinforced concrete slab using externally CNC perforated steel plate. Theoretical study.
Authors: Ubaid Hassan Muhammad , Al-Habbobi Alaa M 
Published: August 2021

Abstract
This research includes the design steps for using solid and perforated steel plate to repair an under reinforcement one-way concrete slab in flexure. All slabs were assumed to be subjected to 85 percent of ultimate load in flexure, therefore the section of the slab to be repairing assumed to be cracked, and the additional external reinforcement represented by the steel plate will be designed according to this assumption and according to the limitations of ACI 318 code specifications. Results of the theoretical calculation indicated that increasing the thickness of the solid plate causes increasing the interface stresses by (72.6%) when replacing the dimensions (width x thickness) of the plate section from (300mm×1mm) to (200mm×1.5mm), while increasing the width of the plate reduces the interface stresses by (48%) when changing dimensions of the plate section to (400mm×0.75mm). Using perforated plate will increase the ductility and reduce the interface shear stresses. Using the plate width to thickness ratio { (bP/dP)=300} will reduce these stresses by (14.8%) when using perforated plate instead of solid one. Increasing the ratio of (bP/dP) lead to reduce the interface shear stresses, as well as reduce the difference between the effect of using solid or perforated steel plates on interface stresses, also when reducing ratio of (bP/dP) the interface shear stress will be increase. Changing the number and diameters of the holes from (10 # 10 mm) to (2 # 50 mm) with keeping the cross-section area of the steel plate constant for both cases increased the resistance of the epoxy nails to the shear stresses that transmitted to them from the axial stresses in the plate by (400%). A new expression is presented in study to calculation the interface shear stress.