bluuebunny/crossref_metadata_2025_split huggingface dataset:
A comparative study of catalyst projects in urban centres: Imam Square in Hamedan
Authors: Shemirani Seyed Majid Mofidi , Alalhesabi Mehran , Zolfigol Sajjad 
Published: March 2021

AbstractCity centres are the vital social, economic, and cultural nuclei of urban spaces, and, as such, revitalisation of city centres’ economic, social, and environmental aspects can significantly improve citizens’ quality of life. Imam Square, as the most pivotal space in the historic and culturally important city of Hamedan in the west of Iran, is one such centre, playing a key role in all nearby urban functions and activities, and affecting both residents’ social lives and local economic features. The “Urban Catalyst” approach is one of the most realistic approaches to improving urban environmental qualities, and this can be used for regeneration programmes to support new urban development policies that seek to recover multiple types of public domain and which acknowledge the primacy of peripheral areas. The purpose of this paper was thus to investigate the urban catalyst project carried out in Imam Square and to compare the resulting situation with the preceding conditions with particular reference to the area’s former central role as a traffic nucleus. This allowed an assessment of the changes following urban catalytic response, another goal of this research. The methodology was based on mixed, with space syntax used to consider the urban configuration and related quantitative aspects and qualitative analysis, developed based on field observations and interviews. The results demonstrated that after pedestrianisation of the central core and the refurnishing of Imam Square, the degree of integration and connectivity of the square and surrounding areas was significantly improved, which has led to an increase in the quality of public spaces and the number of people present.
Microbial fuel cells (MFC) in the treatment of dairy wastewater
Authors: Al-saned Afaf J Obaid , Kitafa Baidaa A , Badday Ali S 
Published: March 2021

Abstract
Microbial Fuel Cells (MFC) appear to offer a feasible alternative to conventional wastewater treatment techniques; thus, constructing and testing MFCs for this purpose was accomplished in this research. The experiments were carried out in two stage; In first stage, synthetic dairy wastewater was used as substrate in an anode chamber using Saccharomyces cerevisiae at different pH values (5, 6, 7, and 8) and different operational temperatures (25, 30, 34 °C in order to evaluate the performance of MFC in term of COD reduction and electricity generation, while in the second stage, the MFC testing was conducted using real dairy wastewater with an initial concentration of COD equal to 2,610 mg/L, inoculated with Saccharomyces cerevisiae in an anaerobic anode chamber under optimum operation conditions. The results revealed that increasing operation temperature had a significant effect on COD reduction and operation time. The optimum pH and temperature were 6 and 34 °C, respectively. After treatment of the dairy wastewater, the COD, TSS, TDS, EC, SO4, and NO3 removal efficiencies of the MFC were found to be 92%, 79.3%, 62.5%, 38.6%, and 60%, respectively. These removal ratios confirm ability of living microorganisms to digest the organic matter present in dairy wastewater to produce electrical power, with maximum values of 850 mV and 28 μA produced for voltage and current, respectively. Microbial Fuel Cell technology thus offers an efficient approach to both dairy wastewater treatment and energy recovery.
The effects of reed fly ash modified bitumen on the volumetric and mechanical properties of open grade friction course mixtures
Authors: Al-Yasari Rand , Al-Busaltan Shakir 
Published: March 2021

Abstract
The global use of open grade friction course (OGFC) asphalt pavements began in 1950, though this practice has gained further interest over time, especially for high-speed high-volume roads, due to the material’s excellent characteristics in terms of skid resistance, drainage control, and noise reduction. Unfortunately, the porous structure of this type of mixture results in other problems related to mechanical and durability properties, despite extensive studies being conducted to overcome such problems using virgin modifiers such as polymers or fibres. Recently, the concept of using recycled and by-product materials as stabilising additives for asphalt binders and mixtures has became more popular, both in order to reduce the construction costs and to increase pavement service life, as well as preserving natural resources and reducing the environmental impact of construction. This study investigates the effect of using one such by-product material, reed fly ash (RFA), as a modifier for asphalt binder and to examine the performance of the resulting OGFC asphalt mixture. The effect of RFA on the OGFC mixture performance is examined in terms of volumetric (bulk density, air voids, porosity and permeability) and mechanical (indirect tensile strength (ITS), skid resistance, and Cantabro abrasion loss (CL)) properties. The results indicate that adding RFA to asphalt binder has a positive influence on mixture performance. In terms of volumetric measures, it leads to increases in air voids, porosity, and permeability of about 17%, 37%, and 102%, respectively at 18% RFA, while the bulk density is reduced as RFA dosage increases. Simultaneously, mechanical properties are increased, with ITS and skid resistance increased by about 10% and >25%; respectively at 18% RFA. However, the resistance to abrasion was enhanced only at lower dosages of RFA (6% RFA), by about 36%. Nevertheless, the use of RFA at optimal percentages appears to offer a sustainable approach to stabilising asphalt binder for OGFC mixtures.
Durability Evaluation: Sustainable Semi-flexible Pavement Mixtures
Authors: Hlail Saif Hameed , Al-Busaltan Shakir , Shaban Alaa M 
Published: March 2021

Abstract
The modern paving industry requires the production of high-performance pavement using more sustainable approaches. Semi-flexible pavement (SFP), prepared by filling an open-graded asphalt skeleton with cement-based grouting material, has been shown to offer high performance for heavily loaded highway and airport pavement applications. The major aim of this study was therefore to evaluate SFP durability based on more sustainable preparation techniques and materials. In this research, a half warm bitumen emulsion semi-flexible mixture (HWBESFM) was designed using local materials and low energy heating technique; the contribution of various sustainable cementitious grout materials on the durability properties of the mix was then evaluated. The developed grouts were prepared using paper sludge ash (PSA) and silica fume (SF) as supplementary cementitious materials (SCM), and the durability of the HWBESFM was assessed with regard to ageing and water sensitivity. The results showed improvements in water sensitivity of HWBESFM containing OPC+PSA and OPC+SF to 66.62% and 65.73%, respectively, compared with the control mix, which demonstrated sensitivity of roughly 55%. Additionally, slight improvements were noticed in ageing resistance on incorporating SCM, those these results remained uncompetitive to traditional SFP mixtures. Overall, this initial investigation of a sustainable approach could, with some improvement, encourage further development and studies in this area.
Python Interactive Cost Control System for Major Contractors
Authors: Ali L T , Khaled Z S M , Ali R S A 
Published: March 2021

Abstract
In this study a computerised management system was developed to aid major contractors in improving cost control performance in construction projects. The system was developed by synthesising all construction cost-related functions into a comprehensive framework, taking into account both cost overrun factors and mitigating measures. These factors and measures were based on the findings of previous studies by the authors, in which 10 cost factors were specified as the most potentially controllable by contractors of an observed 59 influential factors identified in construction projects in Iraq. The system was then developed using Python programming language to incorporate the material, labour, and equipment costs of each construction activity. The system was then compared to in real life implementations in seven types of construction projects undertaken by the State Company for Project Execution of the Ministry of Transport, a major contracting company in Iraq, with the results showing that the system can be successfully utilised by major contractors for cost control during construction.
Degradation of some heavy metals in wastewater using aqua plants
Authors: Janna Hussein 
Published: March 2021

Abstract
The main goal of wastewater treatment is to allow human and industrial effluents to be disposed of without danger to human health or negative impacts to the natural environment. The aim of this study was to evaluate the use of some aquatic plants in terms of the removal of certain chemicals as part of such wastewater treatment. The potential use of the aquatic plant Lemna minor for wastewater purification was thus examined, with Lead, Nickel, Copper, and Cadmium selected as target impurities. The effect of Lemna minor plants on the occurrence of these metals in wastewater for a period of two weeks was thus examined. The results showed that the presence of the plants enhanced the removal of heavy metals: the removal percentage of Lead in the presence of Lemna minor was higher than in the tank with no Lemna minor, with rates of 73% and 47%. In addition, in the presence of Lemna minor, the removal efficiency of Nickel was about 47%, higher than that that without Lemna minor. These results suggest that this plant may decrease the concentrations of some heavy metals and consequently decrease the costs of treating water to remove such metals.
evaluation of seepage under hydraulic structures using gene expression programming
Authors: Khashan Duaa Hadi , Hassan Waqed H. 
Published: March 2021

AbstractThe problem of seepage under concrete dams was studied numerically using finite difference code in MATLAB, after verification with GeoStudio (2018 R2) to determine the lift force under the dams, the head at the third floor of each of the dams, and the exit gradients, which all affect the functionality of these dams. The main goal of this study was to investigate the effects of cutoff locations and depths on the exit gradient and uplift pressure. An empirical equation was thus developed to predict the exit gradient by employing gene expression programming (GEP) and non-linear regression using IBM SPSS based on parameters obtained from the finite difference code. Multiple (327) runs were executed in the finite difference code for a set difference between head upstream and downstream (H=10 m) withvarious cutoffs depth (d/b), with kx/ky = 1 representing isotropic soil. For each d/b value, various cutoffs locations (x/b) were also used, with results indicating that the minimum exit gradient is observed when the cutoff location ratio at the downstream is x1/b=1 with a maximum relative depth of d1/b=0.6, while the minimum uplift pressure is observed when the cutoff location ratio at the upstream is x1/B=0, with a minimum relative depth of d1/B=0.1. The results further indicate that the maximum exit gradient is observed when the ratio of the length of upstream cutoff to the length of downstream cutoff is d1/d2= 1. This exit gradient decrease as the ratio of d1/d2increases. Additionally, the exit gradient decreases with increases in cutoff location and depth, while increasing with uplift pressure. Based on the simulation results, the equation obtained using the genetic expression programming model performed better in terms of predicting the exit gradient than the SPSS model, with a coefficient of determination R2of 0.892 for training and 0.90 for testing. An empirical equation was thus derived to predict the exit gradient based on cutoff 1depth, cutoff1location, cutoff2depth and cutoff2location.
Identifying a Suitable Estimation Method for Evapotranspiration in Wasit Province
Authors: Shamkhi M S , Neamah I F 
Published: March 2021

Abstract
Water is one of the important natural resources due to its applicability to a broad range of contexts, the most important of which are economic and agricultural; indeed, the largest amount of water used by humans is consumed for agricultural purposes. Water resource management is thus very important to managing crises. Referential evapotranspiration constitutes a high percentage of the water consumed in agriculture, making the accurate estimation of ETo values important to determining the quantities of water required for irrigation projects. It also contributes to the planning of water investment and improving management based on predictions about the upcoming hydrological situation. The study area for the current work suffers in particular from a lack of climatic data in the Dujaila region. The focus of this study was thus on possibility of using hydrological methods that require less climatic data as compared to the Penman-Monteith equation to estimate evapotranspiration accurately. The reference evapotranspiration was estimated using the Penman-Monteith (PM-FAO-56), Jensen-Haise, Blaney Criddle, Kharrufa and Hargreaves equations, utilising climate data from the Al Kut Meteorological Station and the Agricultural Meteorological Network for the period 2013 and 2018. The other results then were compared with the reference Penman-Monteith equation in terms of the determination coefficient and mean absolute; overall, the Hargreaves equation was found to be most accurate for predicting the value of ETo, with the values of R2 and MAPE being 0.995 and 6.2%, respectively.
Improving the transportation system in Baghdad city
Authors: Mohamedmeki Mohammed Zuhair , Al-Mumaiz Maha 
Published: March 2021

Abstract
Baghdad has suffered from lack of new major infrastructure in transportation sector for many decades, compounded by a huge increase in the number of roads user. This has led to problems with out-of-date networks causing congested roads and pavement exceeding its design life, increasing travel time with negative effects on users, the economy, and the environment due to increased emission rates and massive fuel consumption. Accordingly, this study seeks to develop a sustainable transportation system to handle a large number of users with minimum effect on the environment to promote economic achievement. Based on the literature, a rail transportation system emerged is the most sustainable system, and such a system is thus proposed for Baghdad, with suggested route and station positions designed to ensure efficient interactions with the current road network. To assess the proposed system, the city was divided into fifteen zones, eight zones on the east side and seven on the west side, and travel times between zones were calculated using GIS software both with and without application of the proposed system. The results revealed that considerable savings in travel time between most zones with the system. Furthermore, the proposed system would change the land use adjacent to access points (stations), boosting investment in housing and encouraging people to leave the overcrowded city centre.
Effects of supply Diffuser Shape on Air Age and Human Comfort in an Office with Displacement Ventilation and Chilled Ceiling System in Hot and Dry climate
Authors: Shbeeb A A , Mahdi A A , Hussein A K 
Published: March 2021

AbstractIn recent years, the need to provide a clean environment in enclosed places has drawn increasing levels of attention due to the spread of epidemics and viruses across the world. Chilled ceilings with displacement ventilation represent promising technology. The combined ventilation system has not yet been used in Iraqi buildings, then it’s a good starting point for study the performance of this system in Iraq-Hilla city climate (hot and dry climate). An office room with a combined ventilation system was simulated using AIRPAK software. Indoor air age, air temperature distribution, CO2 concentration and thermal efficiency were estimated numerically. During the simulation process, the effects of two different supply diffuser shapes (one way rectangular diffuser and semicircle diffuser) were compared to investigated the effect of supply diffuser shape on air age and thermal environment in hot and dry climate (passed on peak summer temperatures in Hilla city). Three tests were performed for each case based on changing the load treated by the chilled ceiling as (25%, 50% and 80%) respect to total cooling load and represented (26, 53, 85W/m2) respectively based on floor area. The temperature of chilled ceiling surface varied as (21.5, 19 and 16°C) and the air supply temperature similarly varied (19, 22, and 24.5 °C) respectively at constant air flowrate of (0.045m3/s). The results of the tests found that the effect of diffuser shape on the local age of air decreased with height, the maximum difference between two cases at the 0.1m level was about 49s while at 2.25m level it was only about 11s. The air exchange efficiency for the CC/DV system using a semicircle diffuser in the predetermined office space was higher by an average of 8.5% as compared with a similar system using a rectangular diffuser; this differential reduced about 3% at each increase in portion of cooling load treated by the chilled ceiling, however.
New spinning technology for producing square section die-less spun parts in the sheet metal forming process
Authors: Saleh A M , Abd A H , Bedan A S 
Published: March 2021

Abstract
Sheet metal spinning is one of the main forming processes, being characterized by flexibility, low cost, reduced manufacturing time, and high formability. Where a flat metal blank is rotated at a high speed and this spun part is formed by pressing a forming tool into the blank, however, this process is limited to axisymmetric parts. This research thus aimed to design and build a simple and flexible mechanism for producing asymmetrical spun parts to allow non-circular forms (polygons) to be formed without interrupting the rotation of the turned blank, being synchronized with the rotation of the special forming tool. The proposed mechanism is based on developing a synchronous spinning machine in which the rotational motion and traditional lathe machine feed are monitored to maintain synchronization with the tool rollers (special forming tool), where the latter controlled by electric motors. The speed of the electric motors is controlled by a variable frequency drive (VFD), pulse-controls and specialized software. The proposed machine can be applied to multiple product shapes by changing the pulse-control in the software code, making the machine much more flexible than other options. Square cross-section parts were formed by cutting aluminum alloy sheets (1050) into a circular shape of 1.5 mm in thickness and 150 mm diameter. The experimental study then examined the effects of various process parameters on the spinning process, spindle speed of the lathe, feed ratio, and forming tool diameter. Three values were adopted for the three parameters, spindle speeds of 48, 68, and 135 RPM, feed ratios of 0.16, 0.22 and 0.32 mm/rev, and forming tool ball diameters of 16, 22, and 25 mm. The results showed that the maximum average in wall thickness reduction was about 27.44 %, and the maximum average error in dimensional accuracy was 6.47 % for spun parts made with a 45 mm mandrel.
A dynamic meshing technique for analysis of nonlinear sloshing in liquid tanks
Authors: Al-Zughaibi A I , Hussein E Q , Rashid F L 
Published: March 2021

Abstract
Fluid sloshing in tanks is a form of liquid surface motion that occurs when an external excitation is applied to a partially filled container. It is an important phenomenon, as the ensuing hydrodynamic pressure on the wall of the tank may cause the structure to fatigue and thus may destroy the tank. This work aimed to study the effects of baffles at different positions in a tank subject to sudden acceleration as part of countering such damage. An ANSYS Fluent model for three different fill levels of tank was used for transient analysis in 2D, while a multiphase model was used to track the free surface of the liquid based on Volume of Fluid (VOF) and a dynamic meshing technique was used to simulate the excitation sources via a User Defined Function (UDF) code in the C++ environment. The numerical simulation showed that the baffles significantly reduced the fluid flow in the partially filled tank, consequently influencing the sloshing pressure acting on the wall of the tank; this reduced the magnitude of sloshing in the tank by 30% and lowered the impact pressure by 21% at maximum, an important design outcome. As the level of fill increased, the pressure also increased, though the baffles limited this variation, leading to low sloshing. In general, the value of pressure inside the tank decreased with increases in the value of excitation frequency in all cases. Validation of the results is conducted by comparing the simulation data with experimental results, and good agreement between them was found, confirming the effectiveness and accuracy of the applied method.
Investigation of an integrated solar thermochemical plant for hydrogen production using high-temperature molten salt
Authors: Sadeghi S , Ghandehariun S 
Published: March 2021

Abstract
One of the most promising methods for producing hydrogen is the use of a water splitting process utilising the copper-chlorine (Cu-Cl) thermochemical cycle. The Cu-Cl cycle uses heat and electricity to produce hydrogen and oxygen from the decomposition of water molecules. In this paper, a new solar-powered integrated system is proposed which utilises (LiNaK)2CO3 high-temperature carbonate molten salt as both a heat transfer fluid and a thermal energy storage medium to provide the required heat for the Cu-Cl cycle reactors and heat exchangers. The system is integrated with a supercritical regenerative steam Rankine cycle (SRC) which produces the required electricity for the electrolyser unit. Thermodynamic and economic analyses were conducted to evaluate the proposed system in terms of hydrogen production cost and system performance. For the base case, the integrated system was found to be capable of producing 823.71 kg/h of hydrogen. The system is optimised for two objective parameters, overall system thermal efficiency and the levelized cost of hydrogen. The results of optimisation analysis indicated that, for the optimal Pareto solution, the overall system thermal efficiency and levelized cost of hydrogen were 29.17%, and $7.58/kg of H2, respectively.
Energy and exergy analyses of a solar magnesium-chlorine thermochemical plant for methane production
Authors: Teymouri M , Aieneh K , Sadeghi S , Ghandehariun S 
Published: March 2021

Abstract
Solar power as the most available type of renewable energy can be used as a clean driving source in the thermal systems. One of the ways to overcome the intermittency problem of solar energy is to convert it into a chemical that can be used whenever it is required. Hydrogen is a good candidate for using it as a fuel. Thermochemical methods for the production of hydrogen are considered as promising candidates. magnesium-chlorine (Mg-Cl) thermochemical cycle is one of the water-splitting cycles that can be used to produce hydrogen. Due to the problems related to storing hydrogen, it is more convenient if we convert it into another chemical like methane. A novel integrated system has been proposed in this study for the production of methane through the Mg-Cl thermochemical cycle. For the base case, hydrogen can be produced with a mass flow rate of 188.32 kg/h. Energy and exergy efficiencies of the Mg-Cl cycle are calculated as 26.25% and 59.88%, respectively. If the produced hydrogen is converted into methane, the methane production capacity of the plant would be 352.98 kg/h. Our results indicated that the energy and exergy efficiencies of the overall system are 7.04% and 60.28%, respectively.