Journal of Engineering and Sustainable Development (JEASD)

The paper presents the study performed to assess the environmental consequences of a proposed organic Rankine cycle-based exhaust heat recovery system for application in vehicles. A life-cycle assessment of fifteen (15) midpoints and two (2) endpoint levels was performed using the SimaPro database to determine the potential environmental consequences of the main parts of the proposed system resulting from the various raw materials used in these parts. The performance results of the organic Rankine cycle-based exhaust heat recovery system show that it can generate up to 3.10 kW of net power output from the engine exhaust, which otherwise is released into the environment as waste heat, with a thermal efficiency of 6.36%. The life-cycle assessment results show that the presence of steel in these components is responsible for the majority of these environmental consequences. The evaporator showed the highest impact potential, with values ranging from 37% in marine eutrophication to 72% in ionizing radiation. From the two (2) endpoint impact assessments, it is clear that the pump has the maximum human health impact potential of 0.0138 DALY, with the condenser having the lowest contribution of 0.0005 DALY. The evaporator and condenser contribute 2297.25 PDF.m2.yr and 158.30 PDF.m2.yr ecosystem quality impact potentials, respectively, as the highest and lowest. Therefore, the organic Rankine cycle-based exhaust heat recovery system has relatively little impact potential on climate change threats, with a value of 1.37E-03 kgCO2.

In recent years, engineers have focused on finding a solution to reduce scouring downstream of piano key weirs. Piano key weirs have high efficiency in flood flow and a higher discharge coefficient. In this research, a type C trapezoidal piano key weir with a type 1 stilling basin was used. Three discharges and three water depths were also used. The results showed that the existence of the stilling basin reduces scour. In the weir with the stilling basin, the maximum scour depth is reduced and the scouring hole becomes more elongated. The maximum distance of the scouring depth increases compared to the toe of the weir. The maximum scour depth and the maximum scour depth distance in the weirs with the stilling basin are about 63.4% less and 20.4% more, respectively than in the weirs without the stilling basin. Additionally, by increasing the flow rate and decreasing the depth of the downstream flow, the amount of scour increases.

Adsorption has been demonstrated to be one of the world's most effective wastewater remediation techniques. This study attempts to use walnut shells as an adsorbent for the removal of the medications Amoxicillin, Ciprofloxacin, and Tetracycline from aqueous solutions. Many variables were studied to indicate walnut shells influence on the efficiency of removal; which included pH of the solution (3-9), drugs concentration (10-60 mg/L), adsorbent concentration (0.025–0.25) g/100ml for the walnut shell, contact time (5-120 min), and agitation speed (50-300 rpm). From the experimental results, the best removal at the most suitable pH value of Amoxicillin at pH 6, for Ciprofloxacin was at pH 5 and at pH 4 for the Tetracycline. With an optimum condition, for an amount of adsorbent of about 0.25, and an optimum time of 60 min for all adsorbs using 300 rpm. The best percentage of removal was 59.32% for Amoxicillin, 62.160% for Ciprofloxacin, and 61.55% for Tetracycline when 50 mg/l concentrations of all pharmaceutical solutions. The removal is well integrated into the Freundlich isotherm model. The correlation of kinetic data by a pseudo-second-order model was successful for three antibiotics. However, this study showed that walnut shells are an effective adsorbent in removing medical contaminants from an aqueous solution of the natural environment.

Many organizations around the world have recognized lightweight, long-lasting, cost and environmentally-friendly construction materials as a future necessity. The lightweight concrete is manufactured mainly either by replacing the original aggregate with lightweight aggregate or addition foam production materials to concrete mixtures. These additions lead to a decrease in the lightweight concrete density and change mechanical properties such as compressive strength. Therefore, there is much experimental research has been conducted to add different material types that can improve lightweight concrete compressive strength while maintaining low density. In this review, the effect of various additions such as steel fiber, product waste materials, and nano-materials on the lightweight concrete compressive strength and density have been explained. The various effects of these additive materials on lightweight concrete properties, some additives lead to improving the properties of lightweight concrete, while other materials lead to a decrease in those properties, and this depends on the type and amount of material additive, the method lightweight concrete manufacturing, and their mixture composition.

In the past, artificial intelligence techniques were successfully adopted for obtaining optimal power flow in a power system. However, this optimality is limited to the economic aspects of the system's operating conditions. The other aspects of the operation, like security conditions, have been given limited attention. Hence, this paper presents an attempt to dispatch the power generation in electrical power systems optimally by taking into consideration both economic and secure operations, so that modern power systems can operate reliably and effectively. Security-constrained optimal power flow is addressed in this paper as a multi-objective optimization problem, consisting of four objective functions: minimizing power generation costs; minimizing voltage deviation; minimizing power losses; and alleviating the overloading on transmission lines. A detailed steady-state generator model is adopted in the present formulation. A metaheuristic optimization technique, namely, differential evolution, is used to obtain the security constraint optimal power dispatch. Additionally, the operating states of a power system have been addressed in this paper. The identification of the operating states is vital to the assessment of the security of the EPS. Improvements and appropriate security assessments have been made in some cases. The proposed algorithm is applied to a typical power system with different operating strategies. The obtained results are compared to those obtained from previous studies in the literature to demonstrate the suggested method's validity and effectiveness.

The environmental behavior of rock and oil pollutants in soil has long been a focus of environmental protection research. In this research, a laboratory model was established to study the oil pollutant transfer process in two stages. Two samples from porous media of sandy soil and agricultural soil (organic) were used with oil as a pollutant. The oil is pumped through a system consisting of two pipes with a length of 4 m and a diameter of 0.07 m. Each pipe is assigned to a specific type of soil. The results showed that the organic soil needs a long time for the pollutants to travel over greater distances, while the sandy soil showed its ability to absorb and drain the pollutants and get rid of them faster. However, it was also found that both soils contain a small percentage of the pollutant after the water washing process, which lasts for more than (5 hours). The remaining oil percentage is estimated at about (0.1 ml), which is a very small percentage, and it is possible to get rid of it by increasing the washing time. It was found that the physical properties of the soil such as permeability and porosity have a significant effect on slowing down the speed of the pollutant and its transmission through the porous medium.

In this paper, the effect of Long-Range wireless technology parameters on signal propagation in suburban environments is investigated. Wireless propagation modeling provides information about the wireless channel and its impact on communication links. Received signal strength and coverage area are evaluated to determine signal path loss. The operating frequency of 433 MHz Long Range Wireless Area Network is utilized with different spreading factors, bandwidths, and code rates. Empirical propagation models are utilized to predict a mathematical model based on measured empirical signal strength in a suburban site in Baghdad City. The measured signal strength and signal-to-noise ratio values were obtained through drive tests in an Internet of Vehicles environment to design a network that could accurately report vehicle locations. The LoRa parameters affected the calculated path loss exponent, leading to various predictions in the network design. The path loss exponent exhibited instability due to the presence of obstacles and different long-range parameter settings. Path loss exponent deviation fluctuates due to bandwidth and spreading factor variations. Path loss exponent reduced at higher coding rates for more protection purposes. Packet ratio reception improved as the coding rate increased. To minimize the impact of the path loss on network design, an optimization policy was employed to determine the best parameters that resulted in the lowest path loss. The optimal path loss obtained at LoRa configuration parameters settings with spreading factor (7), bandwidth (500 kHz), and code rate (4/5).

he Analytical Hierarchy Process (AHP) is a mathematical method which is considered This method is considered one of the most accurate methods in terms of making decisions by providing multiple options so that the decision-maker can calibrate and evaluate the alternatives. The city of Baghdad suffers from stifling traffic congestion due to the increase in population, which leads to a significant increase in the number of trips inside and outside the city, and with this, the number of vehicles is more than the capacity of the city’s road network; especially on the Karkh side. Three alternative roads were proposed in the network; namely: the first alternative is the fourth ring road that connects the Abu Ghraib highway and the roundabout bridge, the second road represents the link between the Washash roundabout and the Muthanna Airport intersection, the third alternative is constructing a tunnel from the Al-Paratha Mosque intersection in the direction of Haifa Street. The purpose of the study is to analyze and select the best alternative by using multi-criteria decision-making. Based on the results, it appears that the economic factor has the greatest effect on the selection of alternatives with its weight equal to 55%, followed by the accessibility factor with a weight of 29.8%. Although the second alternative was chosen as the best alternative in this manuscript, the first alternative is also important in terms of reducing traffic congestion and truck crossing within the city. To increase the efficiency of the network, it is proposed to implement the first and second proposals as well as widen the study region.

In this article, jar and alum technologies were used as treatment materials. Similar synthetic models have been prepared for wastewater from dairy products. The chemical treatment was performed using the jar inspection method. The laboratory temperature, which was between 20-25 degrees Celsius, is a reference in completing the experiments. Experiments have shown that alum can remove phosphorous by up to 95% according to parameters such as the speed of rotation of the oar and the temperature reached in the research. The value of velocity gradient (G) was 1076.915 sec.-1, which represents the potential energy that could make a better crash between particles to achieve an increase in particle size and then settle. This resulted in an optimum aluminum dose equal to 0.5 mg / L at 20 ± 2 ° C. The role of calcium ions in the removal of pollutants has been observed as a catalyst to complete the treatment process, however, it will reduce the aluminum ion concentration necessary to achieve the treatment, it is not possible to risk adding salts over the salinity of water sources to achieve the treatment.

In this paper, a small MIMO antenna with a semi-hexagonal form is developed for use in terahertz applications. The suggested antenna consists of four radiating components printed on a Silicon Dioxide substrate that is 90 ×90 with a thickness of 10 µm. The radiating components have been positioned in an orthogonal orientation to produce excellent isolation and miniaturization of the MIMO system. The suggested MIMO antenna works for all the (0.1-10)THz bands with different values of chemical potential with wide impedance bandwidth (S11 ≤ -10dB) in the frequency range of 2.4 to more than 10 THz, With a co-reflection coefficient less than -20 dB over the whole operating band, with a return loss -50 dB. The MIMO antenna has a maximum gain of 8.4 dBi and a steady diversity performance across all the working bands. According to the high-performance characteristics, the suggested graphene MIMO antenna design can be used for many applications in the THz band, including 6G high-speed wireless communication systems, security scanning, biomedical applications, IoT (Internet of Things), and sensing.

With the rapid growth of high-rise buildings and large-scale structures, there is a need to preserve natural resources and reduce loads on buildings by using lightweight concrete to achieve better performance for structures. In the study, four groups were prepared; the first group included one mix containing natural aggregate, and the second mix replaced all the natural aggregates with lightweight pumice aggregates. These mixes are reinforced with carbon fiber with a 0.5% volume fraction. In the second group, a variable volume fraction of carbon fiber of (0.0 and 1%) of mixes. In the third group, the mixes have different lengths of carbon fiber (20mm, 30mm) and a volume fraction of carbon fibers 0.5%. Finally, the fourth group partially replaces sand as a variable with a percentage of lightweight fine aggregates (10% and 30%) reinforced with fibers. Adding carbon fibers to the concrete specimens by 0.5% and 1% improved splitting tensile strength and flexural strength compared to the specimens containing carbon fibers with a length of 5mm. Also, enhanced samples containing fibers by 0.5% and lengths of 20 mm or 30 mm, compared to the sample containing carbon fibers with a length of 5 mm. Also, the specimens containing lightweight fine aggregates as a replacement with a percentage of sand have a lower splitting tensile strength and flexural strength than the reference mix.

Heat transfer equipment has been used in many different domestic and industrial applications. There has been a concentrated effort to create a heat exchanger design that will reduce energy requirements while saving materials and other costs. Increasing the effective heat transfer surface area or creating turbulence are two common ways to improve heat transfer and hence lower thermal resistance. The thermal Performance Factor is the ratio of the difference in heat transfer rate to the difference in friction factor and serves as a metric to assess the efficiency of heat transfer enhancement technologies. Different types of twisted tubes are used in many heat transfer improvement devices. geometrical parameters of the twisted tube encompassing the aspect ratio, twist ratio, twist direction, twist length, etc. impact the heat transfer. For Instance, oval pipes with unequal twist pitches have a thermal performance factor (1.75) and equal twist pitches have a thermal performance factor (1.98). furthermore, the thermal performance factor of the twisted tube with oval dimples is equal to 1.19 compared with the twisted tube without dimples. The thermal performance factor of the twisted tube with oval dimples is equal to 1.38 compared with the straight tube, with another improvement to the twisted tube that improves the heat transfer properties by disrupting the thermal boundary layer and destabilizing it. This paper presents a comprehensive investigation of passive heat transfer devices (twisted tubes) and their relative merits in a myriad of commercial applications.