Journal of Engineering

The manifestations of climate change are increasing with the days: sudden rains and floods, lakes that evaporate, rivers that experience unprecedentedly low water levels, and successive droughts such as the Tigris, Euphrates, Rhine, and Lape rivers.At the same time, energy consumption is increasing, and there is no way to stop the warming of the Earth's atmospheredespite the many conferences and growing interest in environmental problems.An aspect that has not received sufficient attention is the tremendous heat produced by human activities. This work links four elements in the built environment that are known for their high energy consumption (houses, supermarkets, greenhouses, and asphalt roads)according to what is known as the energy synergyto share them within a thermal network independent of the national network. This research concluded that an asphalt road with a length of 6 km is sufficient to heat more than 800 homes,in addition to valuable benefits accrued by hot countries, such as maintaining the quality of the asphalt layer, prolonging its life, and reducing traffic accidents.The supermarket, which needs cooling every day of the year, can meet its energy needs for cooling in the winter by heating the Greenhouse, while the heat flux is stored for each of the greenhouses and the supermarkets for the rest of the year in the thermal tank (TESS).

Several previous investigations and studies utilized silica fume (SF) or (micro silica) particles as supplementary cementitious material added as a substitute to cement-based mortars and their effect on the overall properties, especially on physical properties, strength properties, and mechanical properties. This study investigated the impact of the inclusion of silica fume (SF) particles on the residual compressive strengths and microstructure properties of cement-based mortars exposed to severe conditions of elevated temperatures. The prepared specimens were tested and subjected to 25, 250, 450, 600, and 900 °C. Their residual compressive strengths and microstructure were evaluated and compared with control samples (CS) subjected to similar conditions (the same temperature category). The outcomes indicated that including silica fume particles in mortar mixtures lowered the amount and width of microcracks, upgraded the mass-loss performance, lowered crystalline calcium hydroxide, and reinforced the cement paste, which explained the improvement in residual mechanical strengths.

This study investigates the potential of biogas recovery from used engine oil (UEO) by co-digestion with animals’ manure, including cow dung (CD), poultry manure (PM), and cattle manure (CM). The experimental work was carried out in anaerobic biodigesters at mesophilic conditions (37°C). Two groups of biodigesters were prepared. Each group consisted of 4 digesters. UEO was the main component in the first group of biodigesters with and without inoculum, whereby a mix of UEO and petroleum refinery oily sludge (ROS) was the component in the second group of biodigesters. The results revealed that for UEO-based biodigesters, maximum biogas production was 0.98, 1.23, 1.93, and 0 ml/g VS from UEO±CD, UEO±CM, UEO±PM, and UEO, respectively, whereby, for the UEO=ROS-based biodigesters, maximum biogas production was 3.49, 2.47, 3.64 and 2.44 ml/g VS from UEO+ROS±CD, UEO+ROS±CM, UEO+ROS±PM, and UEO+ROS, respectively. These results indicated that UEO was not feasible and efficient for biogas recovery since biogas production was very low in the first group of biodigesters compared to its recovery in the second group. A modified Gompertz model was applied to study the kinetics of the bio-digestion process. Measured and predicted values of biogas generation were fitted well with determination coefficients higher than 0.92.

This paper aims to make a historical review of jet grouting techniques and encountered problems at differentsites in severalcountries. This reviewis a good guide to understandingthe performance and limitationsof improved soilsor lands. The basic concept of jet grouting technology is to use cement as a binder to accelerate the hardening process of an admixture of material grout and soil. The different case history wasconducted in both sand soil and clay soil in the horizontal and vertical direction. Otherpapers onfield construction showed that the grout can be gelled within 5-10 minutes. Due to different cases and studies, these will help improve soil by supporting the foundation load with a minimal settlement. The Jet grouting technology can be used in difficultsituations,confinedand unconfined areas,or places with light equipment. Although the jet grouting technique is an ideal modification technique compared to reinforcement and ground treatment support or servesthe foundation, Dams and excavations will save time and cost and increase the bearing capacity.

The need for renewable energy sources is higher than ever due to rising global warming, climate change, and ozone depletion. For refrigeration and air conditioning applications, adsorption refrigeration systems are viable alternativescooling techniques. This study is a topic and part of the M.Sc. thesis. A field solar-powered ice maker unit was created, studied, tested, and evaluated on the 13thand 30thof May,2022. Activated carbon and methanol pair was used to set up a refrigeration system in Baghdad (Al Dora). Experimental tests were carried out outdoors to determine thecoefficient of performance COPandspecific cooling powerSCP of the system. The resultsshowed that the lowest temperature obtained at the evaporative surface was(4oC) and (3oC) for the 13thand 30thof May,respectively,at theopening time of the valve between the evaporator and the generator at 9 pm.In addition,the amounts of methanol condensate were(0.340 kg)and (0.344 kg)for the 13thand 30thof May,respectively, whilethe maximum cyclecoefficient of performance (COP) and specific cooling powerSCPareabout 0.57and 0.14kW/kga.c, respectively.

Substantial research has been performed on Building Information Modeling (BIM) in various topics, for instance, the use and benefit of BIM in design, construction, sustainable environment building, andFacility assetsover the past several years. Although there are various studies on these topics, Building Information Modeling (BIM) awarenessthroughfacilities management is still relatively poor. The researcher's interestis increased in BIM study is based heavily upon the perception that it can facilitate the exchange and reuse of information during various projectphases. This property and others can be used in the Iraqi Construction industryto motivate the government to eliminate the change resistance to use innovations in theIraqi construction industry. Even thoughmany scholars and practitioners agree on the potential application and benefits of BIM in construction/Facilities Management FM, it is yet unknown why BIM is used and what criteria facilitate BIM achievement in O&M. As long as the actual usage and acceptance of BIM in the Operation and Maintenance phase is still a central issue in practice, therefor depending on the extensive well ground literature review a conceptual acceptance model is proposed in this paper by applying the technology acceptance theories such as Technology Acceptance Model (TAM) and Task Technology Fit (TTF) to explore how the extent of facilities management staff going to accept and adopt the new international technology (BIM)

Low- and medium-carbon structural steel components face random vibration and dynamic loads (like earthquakes) in many applications. Thus, a modification to improve their mechanical properties, essentially damping properties, is required. The present study focuses on improving and developing these properties, significantly dampening properties, without losing the other mechanical properties. The specimens used in the present study are structural steel ribbed bar ISO 6935 subjected to heating temperatures of (850, 950, and 1050) ˚C, and cooling schemes of annealing, normalizing, sand, and quenching were selected. The damping properties of the specimens were measured experimentally with the area under the curve for the loading and unloading paths experienced from the tensile test. Considering the effect of different parameters on the damping properties, such as heat treatment temperatures, cooling rates, and carbon content, the results show that the damping properties in the annealing process at different temperatures have interesting damping properties, among other processes. Also, the highest damping energy for the annealing cooling scheme was attained at a heating temperature of 1050 ˚C, irrespective of the carbon content. Finally, better damping properties for the medium carbon content of (0.299%C) is achieved for all types of heat treatment process compared with a low carbon content of (0.188% C); and, in general, with increasing carbon content from medium to low, steel response to heat treatment increases and better damping properties are obtained.

Ensuring reliable data transmission in Network on Chip (NoC) is one of the most challenging tasks, especially in noisy environments. As crosstalk, interference, and radiation increased with manufacturers' increasing tendency to reduce the area, increase the frequencies, and reduce the voltages. Many Error Control Codes (ECC) were proposed with different error detection and correction capacities and various degrees of complexity. Code with Crosstalk Avoidance and Error Correction (CCAEC) for network-on-chip interconnects uses simple parity check bits as the main technique to get high error correction capacity. Per this work, this coding scheme corrects up to 12 random errors, representing a high correction capacity compared with many other code schemes. This candidate has high correction capability but with a high codeword size. In this work, the CCAEC code is compared to another well-known code scheme called Horizontal-Vertical-Diagonal (HVD) error detecting and correcting code through reliability analysis by deriving a new accurate mathematical model for the probability of residual error
????
????
????
????
P
res
​
for both code schemes and confirming it by simulation results for both schemes. The results showed that the HVD code could correct all single, double, and triple errors and failed to correct only 3.3% of states of quadric errors. In comparison, the CCAEC code can correct a single error and fails in 1.5%, 7.2%, and 16.4% cases of double, triple, and quadric errors, respectively. As a result, the HVD has better reliability than CCAEC and has lower overhead, making it a promising coding scheme to handle the reliability issues for NoC.

To finalize any construction investment project, it would be necessary to identify the most significant problems and obstacles that lead to project reluctance and stalling. Unexpected events and conflicts may have disrupted these strategies and impacted project development. Due to the high initial investment costs of construction projects, crises can have an immediate impact, resulting in significant financial losses. The 2014 financial crisis was one of the most prominent crises that Iraq faced, which prompted the researcher to identify and evaluate those obstacles through this research and questionnaires using Pareto scientific theory to exclude factors that do not contribute to project lag. It was discovered that 28 obstacles contribute to project lag before and during implementation. Solutions are obtained by soliciting expert opinions and using the Delphi technique to reach a consensus and a software system to create a proactive plan to reduce and overcome these challenges.

Sustainability is providing the needs without compromising the ability of the strategical forming to meet their requirements. The production of warm asphalt mixtures using recycled pavements produces economic and environmentally friendly mixtures, which is the most important advantage of this work. This research aims to determine the effect of recycled asphalt concrete (RAP) on the indirect tensile strength of warm asphalt mixtures and Marshall Properties. Models of warm asphalt mixtures using Aggregate from the Al-Nibaay quarry, Asphalt with a degree of penetration (40-50) from the refinery of the cycle, and obtained Recycled asphalt concrete from Salah Al-Din Road, Al-Ameriya area in Baghdad are prepared. Use five ratios of (0, 10, 20, 30, and 40%) of recycled asphalt concrete. Marshall Design method is adopted to estimate the perfect existence of the asphalt cement for sample preparation. The mixtures properties, volumetric properties, and indirect tensile strength test are evaluated to assess bonding strength. Results show that the increase in the replacement percentage of RAP causes an increase in flow and air void and decreases the bulk density, voids in mineral aggregate (VMA), and voids filled with Asphalt (VFA). Stability increases with increased RAP content until it reaches its peak and falls. The highest stability value is at 30% RAP by 58%, about the indirect tensile strength test. The increase in the RAP ratio increases the tensile strength and the bonding between the components. So including RAP material in warm asphalt mixtures improves properties and meets performance requirements.

Wastewater recycling for non-potable uses has gained significant attention to mitigate the high pressure on freshwater resources. This requires using a sustainable technique to treat natural municipal wastewater as an alternative to conventional methods, especially in arid and semi-arid rural areas. One of the promising techniques applied to satisfy the objective of wastewater reuse is the constructed wetlands (CWs), which have been used extensively in most countries worldwide through the last decades. The present study introduces a significant review of the definition, classification, and components of CWs, identifying the mechanisms controlling the removal process within such units. Vertical, horizontal, and hybrid CWs were used to treat different types of wastewater from individual households, waste disposal sites, oil refineries, agricultural production, and tannery effluent. The effects of several design and operational factors related to the type of plant, substrate, and flow direction are studied and surveyed in this work to be the starting point for researchers in future investigations.

The designer must find the optimum match between the object's technical and economic
needs and the performance and production requirements of the various material options
when choosing material for an engineering application. This study proposes an integrated
(hybrid) strategy for selecting the optimal material for an engineering design depending on
design requirements. The primary objective is to determine the best candidate material for
the drone wings based on Ashby's performance indices and then rank the result using a grey
relational technique with the entropy weight method. Aluminum alloys, titanium alloys,
composites, and wood have been suggested as suitable materials for manufacturing drone
wings. The requirements for designing a drone's wings are to make them as light as possible
while meeting the stiffness, strength, and fracture toughness criteria. The conclusion
indicates that Carbon Fiber-Reinforced Polymer (CFRP) is the best material for producing
drone wings. In contrast, wood and aluminum alloys were the cheapest materials when the
design had to be inexpensive.