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Go to Editorial ManagerThis article is about studying the placing direction effect of a piezoelectric sensor on the shoe insole in the GRF results. Where the sensors used in this research are in two directions, along and perpendicular to the foot midline. In the both cases the sensors were fixed on the shoe insole to sense the foot pressure. For the first set of sensors which are perpendicular to the foot midline the collected data has similar trend to the GRF collected from the force plate, as the small lateral strain in the shoe insole due to the patient weight and GRF is close to the GRF data collected from other measurement system. On the other hand, the collected data from the second set of sensors which are in a longitudinal direction with the foot midline will have different trend and values from the collected data from the force plate or any other GRF measurement system. This different in the results is due to the large longitudinal strain in the shoe insole due to the patient weight which produce dissimilar results from the force plate result data.
Aluminum metal matrix composites are widely employed for improving the mechanical properties. Various fabrication routes like liquid state, solid state and liquid-solid state are currently available for producing these materials. The objective of the present work is the fabrication of nano particulate composites AA7075-Al2O3 with different amount of nano particles (20-30 nm) reinforced material Al2O3 (2, 4 and 6 wt%) using stir casting technique at three stirring speeds (300, 850 and 1500 rpm). Tensile tests of these composites were carried-out to obtain the mechanical properties (ultimate strength and ductility). Vickers hardness tests were also performed to obtain the hardness number (VHN) of these materials. All tests were performed at room temperature. The microstructures of the best mechanical properties’ composites were examined for the three stirring speeds. It was revealed that the ultimate strength (?u) and Vickers hardness (VHN) for the composite containing 6 wt% Al2O3 fabricated at 850 rpm show the best properties compared to the other composites fabricated at 300 and 1500 rpm and the matrix. The ?u and VHN were increased by about (36.6 %) and (24.5 %) respectively. Ductility of the strongest composite (6 wt% Al2O3 at 850 rpm speed), however, was the least when compared to other composites and the matrix. With increasing the amount of Al2O3, ?u and VHN, an increasing trend was noticed while the ductility shows a reduction trend. The maximum reduction in ductility occurred for the composite containing 6 wt% Al2O3 obtained at 850 rpm. The ductility of the developed composite was reduced by (23 %). The optical microstructures of unreinforced, as-cast Aluminum alloy AA7075 and 6 wt% Al2O3 composites for all stirring speeds show dendrite microstructure resulting from the casting process, but the composite at the stirring speed of 850 rpm shows a more refined microstructure.
Historical records (1901–2021) of Iraq's air temperature and precipitation were studied and compared. A climatic multi-model ensemble and four emission scenarios with representative concentration pathways (RCP2.6, RCP4.5, RCP6.0, and RCP8.5) are used in this research to explain the changes in future climate indicators in Iraq. The results showed a rise and decline in temperatures and precipitation over the past century, with an average of 1.3 °C and 57mm since 1901. A remarkable rise and decline in temperatures and precipitation occurred at 0.36 °C and 4mm per decade over the past thirty years (1990–2020). A greater increase in temperatures occurred in the southern regions than in the northern regions during summer. A temperature increase of 1.5 °C was observed in Basra City and 1.3 °C in Duhok City. The projected temperature over Iraq is higher than historical temperatures in all scenarios, with a rise of about 0.6°C every ten years. Days in June and September with temperatures exceeding 40 ºC have a greater probability of experiencing temperature increases. Iraq is expected to have a decrease in annual precipitation under the high emission scenarios of RCP8.5. The predictions of the medium emission scenarios RCP4.5 and RCP6.0 are noticeably different from the measurements of Iraqi weather stations, especially in 2006. Precipitation decreases from November to May from the historical period in high emission scenarios (RCP8.5) for the foreseeable future. Increased air temperatures and a lack of precipitation have significant effects on the ecosystem because of droughts and frequent dust storms. Therefore, the most important decision that senior management must make is the formulation of policies and procedures for water routing and storage.
As a result of the tremendous development taking place in modern systems and technologies in the field of electronic monitoring. Intelligent monitoring, decision making, and automated response systems have become common subjects at this time, especially after the development of machines responsible for these processes. Traffic surveillance is a trend goal nowadays using different techniques and equipment. In this article, real-time Object detection and tracking techniques were proposed for traffic surveillance using image processing techniques. A state was specifically examined for its ability to detect and count passing motorcycles on a highway in a specific area. The results showed good reliability, with a frame processing time of approximately about (30 ms) and the achievement of real-time performance. The main contribution of this article is reaching the best result implemented by the performance the real-time process using image process technique and tracking the object by depending on the sequencing of frames and can stands with rationally not so powerful machines. Several tools have been used for different types of necessary tasks that will be part of the required application such as Python 3.7; which was used to build the basic algorithms,Visual studio code (VSC) as an Integrated Development Environment (IDE), and Anaconda navigator for downloading many useful libraries. The specifications of the used device were Intel(R) Core (TM) i7- 10750H CPU @ 2.60GHz 2.59 GHz, RAM 16.0 GB, NVIDIA GeForce GTX 1650 GPU, 64-bit operating system, x64-based processor.
Polymer composites reinforced with clay have garnered substantial academic and industrial interest owing to their environmental and mechanical benefits. This research focuses on the effectiveness of metakaolin-unsaturated polyester composites for sequestering Ni2+ ions from Ni(NO3)2 aqueous solutions and on their tribological performance. The composite materials were synthesized with varying metakaolin concentrations (1, 1.5, 3, and 5 wt.%) to evaluate the influence of clay content on nickel ion recovery and wear resistance. The experimental results show a direct correlation between the reinforcement percentage and the functional properties of the composites. The highest value (61.415%) of Ni+2 recovery efficiency was achieved at a metakaolin concentration of 5 wt.%, which is due to the increased density of active adsorption sites on the composite surface. Conversely, composites with lower metakaolin content exhibited diminished recovery rates due to a limited number of available sites for ion adsorption. Wear resistance results show the same trend, wherein the composite with 5 wt.% metakaolin exhibited maximum wear resistance, characterized by minimal material loss at the applied loads (5, 10, 15, and 20 N). Furthermore, Shore-D hardness measurements indicated a gradual enhancement in the material's hardness with increasing metakaolin content, which confirms the reinforcing role of the clay in enhancing the mechanical properties. Scanning Electron Microscopy (SEM) micrographs showed the formation of wear grooves aligned with the sliding direction during wear testing. In addition, agglomerates and surface deposits were formed that are correlated with the adsorption of metal ions onto the composite surface. These results prove that the incorporation of metakaolin as a reinforcing agent confers dual advantages: it significantly enhances the adsorptive capacity for Ni+2 ion recovery and improves the tribological and mechanical properties of the composite. This positions the material for use in environmental remediation, especially wastewater treatment, and in engineering applications requiring enhanced durability.
In this paper, a quick stop device technique and the streamline model were employed to study the chip formation in metal cutting. The behavior of chip deformation at the primary shear zone was described by this model. Orthogonal test of turning process over a workpiece of the 6061-T6 aluminum alloy at different cutting speeds was carried out. The results of the equivalent strain rate and cumulative plastic strain were used to describe the complexity of chip formation. Finite element analysis by ABAQUS/explicit package was also employed to verify the streamline model. Some behavior of formation and strain rate distribution differs from the experimental results, but the overall trend and maximum results are approximately close. In addition, the quick stop device technique is described in detail. Which could be used in other kinds of studies, such as the metallurgical observation.
Both surface extension and nanofluid methods were used to enhance the heat transfer in a double pipe heat exchanger under turbulent flow conditions. Aluminum oxide nanoparticles were used with different concentrations(0.6-3 g/l)in hot water to increase the heat transfer rate on smooth tube and circular fins tube for a range of Reynolds number4240-19790. The simulation was also performed to predict the heat transfer coefficient and temperature profile for selected conditions in which COMSOL Multiphysics is used. The experimental results revealed that the heat transfer enhancement by both circular fin and nanofluid exhibited an increasing trend with Reynolds number and nanofluid concentration. The conjoint effect of Al2O3 of 3 g/l concentration and circular fin provided largest heat transfer enhancement of 53% for the highest Re investigated. Simulation results showed reasonable agreement with the experimental values of heat transfer coefficient. The simulation showed that the presence of nanofluid on finned surface influenced the temperature profile indicating the increased heat transfer rate.
Computational and experimental investigations of thrust vectoring using co flow method had been carried in the present work. The experimental investigation included design and construction of rig with rectangular duct with aspect ratio (4.4) in order to investigate the effect of various geometric variables on thrust vectoring angle. Set of experiments tests carried out over the mass flow ratio ( ) range 0 ? ? 0.23, gap height h/H= (0.0294, 0.0588, 0.088 and 0.1176) and coanda surface diameter ?/H= (1.176, 2.353 and 3.529). _x000D_ Load measurements were obtained using four load cells. The computational investigation involved a 3D numerical solution by FLUENT 6.3.26 Software for some of experimental cases. The results show that the increase in secondary jet blowing rate lead to increase the jet vectoring angle, there are three zone can be observed, dead zone appears at low mass flow ratios, then followed by control region in which continuous thrust vector control can be achieved followed by a saturation region. The coanda surface diameter determines the length of the dead zone, which a small coanda surface used for coanda effect resulted in a prolonged dead zone range and the secondary gap height to the primary gap height had inverse relation with jet vectoring angle. The investigation shows that both the experimental and computational results obtained follow a similar trend line.
Theory in general have been seen from two point of view, in one side, we find that Theory have drawn from the philosophical roots which have its consideration that consistence with people persuasion and researcher's agreement, and from the other side theory is responsible about giving an interpretations and explanations about something in nature or in the cultural social world in a way that it's statements may permit to be tested and analyzed by the action of the research. And because of the interdisciplinary wide range of subjects that may the theory of Architecture builds from , and in order to understand the scientific nature of the Academic Architectural local theorization, thereby we have to explain what do we mean by ( Theory) as a general Concept ,and in Architecture specifically ,in addition we have to explain the wide range of subjects that may the theory of Architecture builds from ,which makes its scientific testing method difficult because of the big parts of its subjects that belong to the human science where concepts like (Subjectivity),(Values),(Ideology) play a Big role in. and so the needs to provide a descriptive framework for the characteristics of the scientific theory in general was risen ,which may be very helpful to distinguish the instructions that achieve the scientific theory in its real meaning within the Academic Architectural local theorizing specifically. From here the research problem where determined by: " we do not have a framework that capable of describe the Academic Architectural local theorization whether it is achieve the criteria of formulating the scientific theorization or not. So the research seeks to:" state the nature of the scientific instructions to formulate the Architectural Theory , and the problem of it in general, and the way that we can classify the theory by, and disclose the theoretical framework which we can use to test the Architectural theorizing (postgraduate students dissertation - M.s.c. & Ph.D.- ) .the research determined the forward mechanism to achieve it's Goal which consist of: defining the meaning of theory in general ,and the position of the Architectural theory in the Theorizing World to reach the characteristics of the general descriptive framework of theory to depend on in testing the Academic Architectural local theorization whether it is achieve its criteria or not. The research conclude that descriptive framework, and explain the interdisciplinary wide range of subjects that may the theory of Architecture builds from, and the way that the theory of Architecture were classified between (Normative &Positivist Theory) and the characteristics of each trend. The Research Findings were summarized that the Normative Theory ( the Argumentational theories especially) which work in (what Ought to be ) Level ,suffered from the difficulty of connecting them with the living world or with the fact the they cannot be tested, and the research also find that these theories by its Hypotheses do not have it's logical connections ( we mean by logic :the relation between Premises & Conclusions),it's Premises institutes on Metaphysical world beyond the real living world ) which work in (what Ought to be ) Level and the differences of their philosophical Structures due to the difference of their basic philosophical assumptions ( Existential , Epistemological ,Methodological ,and approach to the human nature) that adopted by the researchers. The research recommended the necessity of distinguish between the theorizing criteria for subject research that belong to the two level of hypotheses (what ought to be -level, & and the level of -what it is exist already) where it is not valid to conclude one from the other because they have different testing criteria.