Journal of University of Babylon

Surface engineering of Al alloys by deposition of hydrophobic coatings using different techniques to improve the wear and corrosion resistance and self-cleaning properties has gained more attention in the last years. This study is an attempt to use thassos additives in modification of the electrolytes used in the micro-arc oxidation MAO process for the deposition of hard and super hydrophobic Al2O3 ceramic coatings on Al alloys for heavy load-bearing tribological and self-cleaning applications. Thassos rocks in different concentrations (1, 2, 3, 5 and 7 g/L) were used as modification components. Ceramic coatings of Al2O3 were deposited on Al alloy by using a homemade MAO unit with an applied voltage of (320-350) V, current of (0.1-0.3) A and a temperature of (15-25°C), and at different deposition times (10-45min). The coated surfaces were post-treated using fatty acids such as myristic acid (10g/L) and stearic acid (5g/L) for important self–cleaning properties. Various analytical techniques and tests were used to characterize the coatings such as scanning electron microscopy (SEM), X-ray diffraction (XRD), hardness, thickness, and angle of contact measurements and tests. The highest contact angle of 95.120° was achieved when using thassos (3g). This high contact angle indicates that the surfaces are highly hydrophobic, which means that they repel water effectively. The best result for the highest hardness value recorded was 975.9 HV when using thassos (7g) as additives. Results from this research will promote future works in surface engineering of Al alloys by MAO process using more environmentally friendly, readily available and require minimal process additions such as ceramic natural additions of thassos in the deposition of hard and hydrophobic ceramic coatings for wear resistance and self-cleaning applications.

With the growth and development of Iraqi cities and the increase in population density in cites’ centers, the development of cities and urban areas involves focus on economic concerns, often resulting in the exclusion of people with disability from participation in meaningful urban activities. In recent decades, technological advances and social awareness have made accessibility more common for people with disability. However, major disparities remain in people's access to basic support services and opportunities. To ensure that all citizens can benefit from the revitalization of city spaces, it is essential to integrate empowerment strategies for people with disabilities into urban open spaces. The implementation of such strategies can lead to the empowerment of disabled people in urban areas by providing them with access to public spaces, transportation networks, and other services. Therefore, the research problem is concerned with the need to find mechanisms to integrate people with needs into urban spaces through the urban empowerment strategy for people with special needs, and thus revitalize the city's spaces and achieve a healthy, safe, flexible and sustainable environment.
This new design strategy aims to empower and improve the lives of people with diseases, physical disabilities, and mental health impairments by giving them access to social networks, resources, employment opportunities, and leisure activities that enhance the quality of life in cities. It also plays a crucial role in developing an environment that meets the unique financial and personal requirements of disabled people. The paper examines this issue by adopting the descriptive analytical approach, the research employs a questionnaire as a data-gathering technique and the data was analyzed using the Microsoft Excel program. The results showed that there is a clear gap in what is currently provided to disabled people in this city and the development plans for the year 2030. Moreover, the study showed that there are problems in applying empowerment strategies in the development and revitalization of urban spaces.

Distribution networks of electrical power are becoming increasingly active through integration of small generating units. However, the topology of the distribution network may hinder large scale integration of those generating units thereby decreasing the benefits of an active distribution network. Soft open points (SOPs) are considered one of the solutions to alleviate the hampering of integration of local sources by altering the topology of the distributed network.
In this paper, the problem of finding the optimal operating points of SOPs are analyzed and investigated. Two approaches are adopted; by using single objective particle swarm optimization (PSO) and multiple objective (MOPSO). In the former, a set of objectives are optimized on a one by one bases whereas in the second method, the set of objectives are optimized together at the same time. The set of objectives are the typical, active power loss, voltage profile and feeder load balancing. A comparative approach is adopted in this paper with the intention of finding the best approach that yield optimum points. Optimum points which are defined as a set of active/reactive powers for each converter of the SOP. These optimum points are further employed by designers as reference settings for the control system which governs the local operation of the SOP system.
Results from simulations carried out on the IEEE 33 bus system with and without multi capacity local energy sources, shows that the three objectives are better optimized using PSO than MOPSO keeping in mind that the PSO requires less computation effort compared to MOPSO. Moreover, better PSO performance is observed as the amount of power injected by a distributed source (DG) increases. The former is also true when the system is optimized by MOPSO.

The rectangular opening which is 20% of the apex wall area works as a gate within a two-cycle sharp-crested labyrinth weir, reduces the effects of immersion upstream, and allows passing sediments. In the result of experimental investigation, the discharge capacity of the labyrinth combined flow related to geometric dimensions; that is where the increase in the sidewall and the apex lengths reduce the immersion, while the discharge increases (23-32%) and when the weir crest level increases about (30%). The combined discharge coefficient decreases when increasing the ratio value of the head to the weir height, its value also decreases by (6-21%) when increasing the sidewall length 3 times. The proposed equation for predicting the combined discharge is within (0.07-0.16%) of the measured discharge. The contribution analysis of each discharge part of this structure indicates the gate passes (40-60%) less than discharged from the weir due to the submergence; Moreover, this state causes head lifting on the weir crest by (26%) and this increases is reflected as an advantage to the weir in its discharging.

This research is devoted to investigate experimentally the flexural behavior of cold-formed steel I-beam with strengthened hollow rectangular flange (RHFCFSIB) under four point loads at the same distance from the support. All specimens have the constant clear span of (L=1500mm), a constant beam specifications (t=4mm) web and flange thickness , (h=300mm) for beam′s depth and flange width of (bf=150mm) and flange depth of (hf=60mm) .The spacing between the bolts that connect the web to the flanges was (L/6) and eight stiffener for each beam were placed under the load bearing points and at the support points on each side. The experimental program includes assembling the parts to make beams and testing of five specimens tested under four point loads, one of these specimens was not strengthened, which used as a control specimen. Four specimens strengthened with different strengthening materials, light weight, cost and strength are the main factors for choosing this material (normal concrete, normal concrete has been replaced coarse aggregate by recycled concrete, normal concrete has been replaced fine aggregate with 30% sawdust and normal concrete has been replaced fine aggregate with 30% coarse rubber). The strengthening beams were compared with the control specimens, It was found from this compaction that strengthening the flange with different strengthening materials improved the behavior of the beam, as the bearing capacity increased in rates ranging between 15.8% and 27.98%, the deflection decreased in rates ranging between 65% and 83% , this means that strengthening flange has a strong influence on the flexural behavior. The main conclusions drawn from the study were discussed and summarized, the research shows that the strengthening hollow flanged sections gave best results for flexural behavior.