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Go to Editorial ManagerDue to the Kurdistan regional government-KRG district mission potential towards huge solar energy power generation plant investments by global investors, a genuine study is required to explore the impact of PV-panels installation angles on power generation gain within all seasons duration as the KRG located in four season area which, affect the annual total power gain due to daylight duration effect in each season. The proposed study was conducted within a duration of “513” days utilizing three PV tilt installation angle tests of “ 30⁰, 35⁰, and 40⁰ ” with “ 545 watts single side PV plates” selecting the Erbil district area gaining a crucial role in maximizing energy output for comparison, Results presented a significant variation in power gain due to deviations in annual effective daylight duration effectively mostly a reduction in cold seasons within 25%-37.7% drops compared to the hot season, while the sunset and sunrise duration presented a significant influence of 5%-10% drops in power generated. The season change shows a significant influence of weather variation in each calendar on power gain annually. The installation orientation angle impact presented divergence in production within the cold season only. Process output can potentially unlock a novelty awareness of the investors toward innovative yield project optimization in the area as it will affect the annual power purchasing influence and production divergence with interest.
The aim of this work is to optimize EPD variables (voltage, time, and focus) using alternating current through the Taguchi Design of Experiment (DOE). Coating Nano hydroxyapatite (Nano-HA) on a Ti6Al4V substrate depends on thickness and roughness, then characterization of a coating layer to determine the optimum state. Hydroxyapatite (HAp) powder was deposited on a Ti-6Al-4V alloy substrate by electro-deposition with ethanol as a solvent under AC current, to improve the alloy surface quality based on coating thickness and maximum coating mass meeting the requirements of a biological orthopedics application. Ethanol was used as a solvent to precipitate ketazone and HAp on the base alloy. Taguchi's approach was used in order to determine the optimal conditions for EPD and subsequently to apply various criteria for depositing the biochemical coating. The surface and cross-section composition of the paint is described by characterization. Numerous tests and inspections; Zeta, XRD and SEM stability test, water contact angle and optical microscopes were used to describe the surface morphology of the HAp layer. The value of the optimum conditions for deposition of the HAp layer which is a simultaneous thickness and maximum coating mass, was predicted at a sedimentation voltage of 40 V, 2 min sedimentation time and 1 g / L for the concentration of the suspended solution at room temperature. The validity of the model resulting from the response surface methodology was assessed by comparing the expected results with the experimental results. In addition, close agreement was observed between the experimental results and the expected results. For the solution at room temperature, the results obtained with the highest value of the coating thickness of 41at the surface roughness of 0.94 and the contact angle of the alloy before coating is 67.489º reduced to. 38.132º after plating, which indicates an increase in the harmony of the metal implant and biocompatibility.
The effects of the repeated solution heat treatment on hardness, tensile strength and microstructure of aluminum were investigated. For this purpose, an alloy of AA6061-T6 was undergo to cyclic solution heat treatment process which is composed of repeated period (10 min) held at 520 °C for 1, 4, 8 and 12 cycles. The hardness was tested for five aging times (as quenching, one week, three weeks, one month and five months) to all cycles (1, 4, 8 and 12) firstly and it is found that the hardness of five months as aging time for all cycles has the best results (90Hv) as compared with others (as quenching, one week, three weeks, and one month), so it was adopted for all cycles to implement the tensile test and the microstructure. Hardness results were improved to Vickers hardness of (90Hv) with increasing of cycles up to 8 cycles then decreasing after that to (45Hv). Tensile results were showed an increment (34%) also for the same group of 8 cycles compared with (17%) and (9%) for 4 and 12 cycles, respectively. Microstructure is revealed that whenever cycles are increased, the precipitate phase in alloy is increased also, thus, it is improved the hardness and tensile strength.
In this work, the vibrations in the rotor-bearing system are studied experimentally and theoretically using ANSYS Workbench 2020 R1 software to compute the natural frequencies and mode shapes. In the experimental part, the LABVIEW software was used to examine the signal of the frequency domain values obtained from the accelerometer sensors, based on Fast Fourier Transform (FFT) technology and dynamic response spectrum. in the theoretical part, the natural frequencies are determined based on the finite element method for analyzing the system and knowing its behavior and vibration response level. The results showed that the level of vibration becomes higher at high rotational speeds, and it becomes large when the distances between the bearings are large, according to the bearing position and type used in the system. in this work can be concluded, the system is usually affected by the dynamic response around it and is difficult to separate from it, and the vibrations in the system can be controlled by adding an external damping source, which gives the system more stable. A system operating at high speeds can give a large vibration and an unbalanced response.
In this vast world after an earthquake lessons are learned; many strategies have been considered in order to achieve a proper seismic strength capacity.The aim of this paper is studying the seismic behavior of a typical reinforced concrete bridge pier in Iraq and implementing a proper technique of strengthening in order to fix any damage that had happened.Structure of a full scale three-dimensional finite element model was used in order to simulate a reinforced concrete pier via the computer software ABAQUS/CAE 2017 using concrete plasticity damage model (CDP).Under the action of Halabja earthquake, which was recorded at city of Halabja in Iraq on 12 November 2017, the behavior of model was traced, analyzed and the resulted damages were managed.The finite element analysis results indicated that the proposed configuration of carbon fiber reinforced polymers laminates substantially increases the lateral load strength and deformation capacity of the bridge pier
In recent decades, many factors have emerged in the building design field, as the technology development after the industrial revolution has left many environmental problems affecting building environments and turning them into unhealthy ones. Also, the issues of consuming natural resources required innovative and modern solutions to address, which needed the guidance and focus of researchers, engineers, and many other relevant disciplines to find the best treatments to solve them. One of the essential treatments was using advanced smart technology to solve the environmental problems of buildings, such as providing thermal comfort and reducing energy consumption. The concept of adaptive smart envelopes is one of this manifestation of advanced technology in the field of building design characterized by interaction and adaptation to the surrounding environment through the application of many technologies which it works to improve its environmental efficiency. The research aim was to simulate the changes in the building environment, which is treated by covering the building with an adaptive smart envelope by using the Rhinoceros Grasshopper programme.
With the development of manufacturing techniques, the demands have increased on tools with flexible components that can produce parts with different shapes and sizes only by replacing the rigid part of these tools, since the flexible part can match the required geometry. This study is focused on effects of rubber hardness and sheet thickness on the springback developed on the produced parts. Silicone rubber with three hardness (40,60 ,80) Shore A hardness scale was used. The material of workpiece was Aluminum (3003) with three different thicknesses of (0.8,1,1.2) mm and three holding time of (0,10,20) seconds. The results demonstrate that, the springback decreases with any increase in the rubber hardness or sheet thickness. In addition, the holding time showed a significant effect only with a harder rubber.
Türkiye possesses abundant geothermal resources. It is ranked seventh globally for this particular energy resources and grade among the first 5 in utilizing geothermal and thermal springs for various purposes such as electricity generation, residential cooling and heating, greenhouse operations, desiccating processes, thermal recreation, therapeutic applications, mining, agricultural uses, and aquaculture. The government's endorsement from renewable power sources is fueling growing interest on this particular energy sector. This article provides a comprehensive analysis of geothermal energy in select locations of Türkiye, including an assessment of its potential and various applications. The study seeks to provide a valuable involvement to the future advancements of a geothermal technology on Türkiye.
In this work, the design procedure of a hybrid robust controller for crane system is presented. The proposed hybrid controller combines the linear quadratic regulator (LQR) properties with the sliding mode control (SMC) to obtain an optimal and robust LQR/SMC controller. The crane system which is represented by pendulum and cart is used to verify the effectiveness of the proposed controller. The crane system is considered one of the highly nonlinear and uncertain systems in addition to the under-actuating properties. The parameters of the proposed LQR/SMC are selected using Particle Swarm Optimization (PSO) method. The results show that the proposed LQR/SMC controller can achieve a better performance if only SMC controller is used. The robustness of the proposed controller is examined by considering a variation in system parameters with applying an external disturbance input. Finally, the superiority of the proposed LQR/SMC controller over the SMC controller is shown in this work.
Recently, considering polymer composite in manufacturing of mechanical parts can be caused a fatigue failure due to the very long time of exposure to cyclic loading and may at environmental temperatures higher than their glass transition temperature; therefore, in this paper, a comprehensive investigation for bending fatigue behavior at room and elevated temperatures equal to 60 °C, 70°C, and 80 °C will be done. Rotating bending test machine was manufactured for this purpose supplied with a connected furnace to perform fatigue tests at elevated temperatures. The obtained results appeared that the increase in applied stress and temperature caused a clear reduction in fatigue life; also the addition of carbon nanotubes enhanced the fatigue life at different temperatures by 183%, 205%, 218%, and 240%, respectively while the addition of short carbon fibers improved fatigue life by 324%, 351%, 387%, and 415%, respectively. As well as, Polyamide 6,6/carbon fiber composite appeared fatigue limit at temperatures equal to 20°C and 60°C and stresses approximately equal to 55 MPa and 38 MPa respectively.
The partial shading conditions have a significant effect on the performance of Photovoltaic system and the ability of delivering energy. In this study, the impact of different partial shading on the mono crystalline (88W) PV module performance was investigated in this study. Horizontal string, vertical string, and single cell shading at different percentage of shading area have been studied. It is found that the horizontal string shading is more severe on the efficiency of the PV panel. In contrast, the efficiency of PV panel with cellular and vertical cell shading was less during the tests. The experimental results showed that the power losses were 99.8%, 66% and 56.8 % for horizontal, cellular and vertical shading respectively via applied non transparent material as shading element by 100% of shading area at 500 W/m2. Moreover, transparent material used to shade whole module horizontally, different shading area and different radiation level applied to find electrical characteristics of the module under these conditions. The results show that at 800W/m2 of irradiation levels and no shading condition the power was 68.6W, by increase shading area by 20% in each step, the power reducing by 44.94, 47.58, 49.42, 50.57 and 52.4% in compared with their initial value at no shading condition.
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Poly(vinyl chloride) photodecomposition films that contains melamine Schiff base (0.5% by weight) as photostabilizers upon preservation with an ultraviolet light (UV) was investigated. The photodecomposition rate constant was reduced significantly in existence of melamine Schiff base compared to PVC (blank). The Schiff base 1 was found to most effective additive in PVC photostabilization films. Photodecomposition rate content for PVC films containing Schiff base 1 was found to be 5 × 10-3 sec-1 compared to 8.7 × 10-3 sec-1 for blank film. Ultraviolet radiation aging behaviors of PVC films were studied through leaching test by measuring the degree of migration. The surface morphology of PVC films was inspected by scanning electron microscope.
In the field of engineering, 3D printers are indispensable due to their high precision. This study focuses on the construction and optimization of a 3D printer using aluminum T-slotted bars for the frame, Raspberry Pi 4 for control, and Lightburn software for image printing and machine control. After assembling the main components and programming with Marlin firmware, the machine was tested for vibration and noise reduction. The research compared the vibration of a diode laser and spindle during printing, revealing significantly lower vibration with the laser compared to the spindle. These findings demonstrate the effectiveness of the constructed 3D printer in reducing vibration and noise during operation.
In Republic of Iraq, ready-mix concrete production plants have been adversely affected by the lack of modern and advanced technology to assess their performance in line with technological advancements. Current evaluation methods rely on traditional approaches and financial measures, yielding unrealistic performance results. To address this problem, there is a need to utilize modern models and methods for performance evaluation. The study's main objective This was achieved by employing a literature survey methodology and utilizing digital databases such as the Iraqi Scientific Journals website, virtual libraries, and scientific platforms like ScienceDirect, Springer, Google Scholar, and Gate Research between 2015 and 2023. The research study provided a comprehensive overview of performance evaluation, including its definitions, importance, and an introduction to modern models and evaluation methods. The study found that no previous studies have been conducted in Iraq to evaluate ready-mix concrete production plants. However, four studies were found in Egypt, Sudan, and India. The previous similar relevant studies discussed various topics and related studies. Firstly, they discussed the classification, advantages, and disadvantages of concrete mixing plants. Additionally, the previous studies analyzed the factors that most influence the performance of concrete production plants, including laboratory manager efficiency, work team efficiency, communication and relationships within work teams, plant operator, material transportation method, and time and courses. Furthermore, the previous research studies present a comprehensive analysis of all variable data simultaneously using the statistical package for Social Science (SPSS) input stage. The evaluation also extends to the evaluation of laboratories, encompassing plant arrangement, internal quality control systems, and final product quality. The overall evaluation results of previous studies. Indicate that 75% of the concrete production plants failed to meet the required criteria, while only 25% demonstrated satisfactory performance. The study proposed improvements to enhance the performance rate of ready-mix concrete production plants by leveraging the most influential variables, which will be considered in the study.
A new robust control algorithm is proposed for a class of nonlinear systems represented by a Single Link Manipulator (SLM) system. This algorithm is based on new techniques and methods in order to obtain a controller for the SLM system. First of all, the system is simplified using Variable Transformation Technique (VTT) in order to fit the analysis procedure. Then, a new idea of designing a model reference for the multiple states (n=4) system is presented to correspond the control design. Next, the Lyapunov Stability Analysis (LSA) is used to figure out a proper controller that can compensate the stability and the performance of the SLM system. After that, the Most Valuable Player Algorithm (MVPA) is applied to find the optimal parameters of the proposed controller to accomplish the optimum performance improvement. Finally, it can be concluded that the proposed control algorithm has improved the stability and the performance of the SLM system. In addition, the simulation results show the remarkable effects of the proposed nonlinear controller on the SLM system.
Orthoses and prostheses were Chosen and laminated based on their high Yield, ultimate stresses, bending stresses, and fatigue limit. Response Surface Methodology (RSM) was utilized to find the best values for two parameters reinforcement perlon fiber and percent of Titanium Nanoparticle coupled with the matrix resin during optimization. The response surface methodology combined the expertise of mathematicians and statisticians to construct and analyze experimental models. Using this method, we identified 13 different lamination samples comprising a wide range of perlon number and Ti nano Wt% in their Perlon layer composition. All lamination materials defined by RSM methods and produced by a vacuum system were subjected to a battery of tests, with fatigue tests performed on the ideal laminating material in contrast to laminations created in the first study (Tensile test, Bending test, and Fatigue tests according to the ASTM D638 and D790 respectively). In comparison to the other 12 laminations tested using Design Expert version 10.0.2, the lamination with ten perlon layers and 0.75 percent Ti nano proved to be the strongest overall in terms of Yield, ultimate, and bending loads. This study used composite materials and titanium nanoparticles to characterize and fabricate ankle foot orthoses. Strength in bending should amount to about 70 MPa, around 85 MPa in tensile tension. Two empirical quadratic equations for the models of peak bending strength and maximum tensile stress with 95% confidence were created using the response surface approach and analysis of variance within the design of experiments software.
An experimental and theoretical study of free convection heat transfer for a cylinder placed in an iron test section of dimensions (0.2x0.2x0.2 m3), the test section filled with saturated porous material glass balls (5 mm), and the air is the working fluid with Raleigh number (7692.6 ? Ra ? 17654). The circular cylinder heater (D = 0.015 m, L = 0.2 m) is heated electrically, made of Copper and located in different positions (in X & Y direction). The theoretical part includes solving the free convection heat transfer using the ANSYS program (fluent). The experimental and theoretical results showed that the surface temperature values around the cylinder perimeter when changing its position within the test section are changing as moving up and down where the effect of buoyancy force appears. The maximum difference between the upper and lower position at the experimental result is 7.22%, and the average Nusselt number increases with Raleigh number and heat flux. Also, the experimental results showed that the use of porous material significantly improves the heat transfer by 48.6%. The maximum percentage change between the experimental and theoretical results is 5.46%. Moreover, experimental correlations were achieved, and a comparison was performed between the present results with the previous studies and it gives a good agreement.
The phenomenon of climate change resulting from the increase of global warming has become one of the main problems facing the world. Where researchers and specialists have worked for many years to find a solution that reduces this phenomenon and limits its risks. It is likely that clean energy is an alternative to fossil fuel sources, which are the main source of global warming. One of the clean energy sources is ocean wave energy, which is a huge and untapped energy source, despite the possibility of extracting large energy from waves. This paper focuses on the study of deep-sea turbines and their results. A study was conducted on the capture chamber. Where this paper presents an experimental model of a water tank with certain dimensions in the university laboratories to describe the dynamic behavior of the capture chamber. The Froude number scale was used to model the dimensions and depth of the water as well as the wave properties. Through experimental work and its results show, and it was found that the power generated by the motion of the wave strength is related to the height and frequency of the wave.
Open graded asphalt mixture is becoming more widespread where it is applied for various purposes, e.g. drainage of rainwater effectivity, traffic safety (high skid resistance), and controlling pollution noise. However, it has many other disadvantages, of which low stability, high stripping, and moisture sensitivity. The research aims to study the effect of styrene butadiene styrene SBS addition on the volumetric and mechanical properties of open graded mixture. In this research one type of aggregate with gradation (12.5 mm NMAS), asphalt of penetration grade (40/50), and cement as filler were used. Optimum asphalt content was selected based on the criteria of air voids content, asphalt drain down, permeability, and abrasion resistance (for aged and un-aged) samples. Other properties of open-graded mixtures, such as indirect tensile strength (ITS), moisture susceptibility, Marshall stability and flow were evaluated. The results show that addition of polymer (SBS) leads to an enhancement in the properties of the modified mixtures. There is an improvement in Marshall parameters. Also, a slight decreasing is noticed for permeability and air voids. For Cantabro abrasion loss (aging and un-aging condition), the abrasion resistance is increased, the drain down of asphalt is decreased from original mixture by addition of SBS. Finally, the moisture sensitivity is improved indicating that modified mixes becomes more resistant to water damage.
This paper provides a comprehensive overview of microfluidic device (MFD) manufacturing processes. The review starts with an introduction elucidating the significance and advantages of MFDs. Subsequently, a brief description of the materials employed in MFD fabrication is presented. The manufacturing process used to create MFDs is then thoroughly examined, with a focus on the application of laser technology.
The most important way for joining the non-welding aluminum alloy is Friction stir spot welding. Three parameters effect on efficiency of welding: tool shape, rotational speed, and plunged time, are chosen to study for welding 6061T6 aluminum alloy. Each of the above parameters has three variables as: pin shapes (square, cylinder, and hexagonal), plunged time (50, 70,100) sec and rotational speeds (710, 1120, 1800) rpm hybrid approach which is consist of the experiment run, neural network and social spider optimization is used to optimize the welding conditions by finding the maximum ultimate force. The best condition of the weldments is (square, 710rpm, 100sec) with maximum shear force 4740N. The best results obtained from hybrid optimization with experimental results; with discrepancy of 2%.
Medical image segmentation plays a crucial role in the realm of medical imaging. The process involves the division of an image to obtain a comprehensive view and ensure precise diagnostics. There are various methods that are employed, ranging from traditional approaches to the more advanced deep learning techniques. Both play a significant role in enhancing healthcare. With the continuous advancement in technology, there is a growing need for accurate segmentation. While traditional methods such as thresholding and region growing are effective, they may require human intervention for complex cases. Deep learning techniques, particularly Convolutional Neural Networks (CNNs), have significantly improved the process by learning intricate details and accurately segmenting the image. When these methods are combined, healthcare professionals can achieve high-quality, precise results. Furthermore, with the advancements in hardware and technology, real-time segmentation is now possible. Generally, the process of dividing medical images into segments is extremely important for the progress of healthcare with the help of artificial intelligence and the most recent advancements in the industry, such as explainable AI and multimodal learning. However, this meticulously detailed and in-depth review provides an all-encompassing and extensive analysis of the current methods utilized, their multitude of applications across various fields, and the promising emerging advancements that have the potential to pave the way for remarkable future improvements and innovations.
The aim of the research was for evaluation the morphological and chemical alterations that result from the Nd:YAG laser treatment of dental enamels using optical microscopy (OM) with Energy dispersion X-ray spectroscopy (EDX), respectively. Two human enamel samples were obtained, the samples were exposed to the Nd: YAG laser irradiation. The micrographs obtained by optical microscopy demonstrated morphological changes. The concentrations of carbon (C), calcium (Ca), phosphorus (P), and oxygen (O) in crater sites and its environs were measured using EDX, as well as trace amounts of manganese, magnesium, and silicon. However, due to their low concentration, these trace elements were neglected. We obtained the maximum depth profile of carters on tooth enamel surface at 1200 µm with laser pulse of 532 nm with 500 mJ energy/pulse, while the minimum depth profile of carters at 200 µm with laser pulse of 1064 nm with 100 mJ energy/pulse. Dental tissue can be safely treated with a Nd: YAG laser with 200 mJ, 9 ns, and 1064 nm since this laser irradiation range did not induce any noticeable morphological changes. As a result, the Nd: YAG laser offers as an ideal option for clinical treatment.
Platinum, copper, and nickel were founded the best metals used in resistance temperature detectors RTDs. They commonly used in laboratory and industrial applications because they provide accurate and reliable measurements in a wide temperature range from (- 200 to 850 °C). They have high conductivity, sensitivity, and hardness to resist strain shock, pressure, and vibration. The accuracy level of them depends on reliability, stability, repeatability, linearity, and response to time. This study aims to determine and compare the accuracy of these three metals in regarding to their features which include stability, repeatability, and response time. The study has gathered and analyzed the data of these suitable and precise metals and compared with each other. The results showed that platinum is widely needed for RTDs due to its precision, stability, higher accuracy, and linearity output, while copper and nickel are not stable or repeatable as platinum. It was indicated that temperature coefficient of resistance TCR for nickel is bigger and for copper is medium, but for platinum is lower.
The field of mechanics concerned with studying the propagation of cracks in materials is Fracture Mechanics. Technology systems are meant to withstand the loads to which they are likely to be exposed when in use. Material imperfections arising at the time of production or use of the material are, however, unavoidable and must therefore be taken into account. A stress intensity factor is a fracture parameter that defines the part failure. This paper study’s the effect of cracks on the stresses of rectangular plates having a hole in the center. The plate was subjected to tensile pressure at the top side while maintaining the bottom side fixed. The plate had four cracks distributed around the centered hole at 45o at each side. The effect of the length of the cracks on the resulted stresses and strains was investigated. Also, the effect of the position of the crack on the resulted stresses and strains was studied. Finite element models for the different plate cases were built using ANSYS software. The results showed that increasing the crack length resulted to increase the stresses and strains. The dimension of the plate width, height and thickness were 150 mm, 300 mm and 1 mm respectively, and the crack position was investigated for different crack lengths (5, 10, 15, 20, 25 mm) however the results were not steady as it looks that the crack lengths have changed the stress distribution over the plate.
Rutting is the most common distress that most Iraqi asphalt pavements suffer from it. Asphalt binders are modified by using additives and polymers to enhance their physical qualities and fulfill the performance demands. Polyphosphoric acid (PPA) has been used in many countries to enhance the physical and mechanical characteristics of asphalt binders and mixtures that can improve the performance of asphalt pavements. In this paper, evaluation of the Iraqi asphalt binder and mixtures performance by using three percentages of Polyphosphoric acid (PPA) (0.4, 0.8, and 1.2) percent by asphalt binder weight and added to (60-70) penetration grade asphalt binder to show the applicability and suitability of using PPA in asphalt pavement in Iraq. Original asphalt binder and modified are subjected to traditional tests which are penetration, ductility, softening point, and viscosity. Results show better performance and enhancement of the physical properties of the modified binder. Other tests are Marshall Stability and wheel track tests. The results of the addition of PPA to the asphalt mixture show increases in the Marshall Stability and enhance the performance of the asphalt pavement mixtures. The wheel track test is applied to the original and modified mixture at two test temperatures 40 ?C and 50 ?C and the results show a decrease in the rut depth when the percentages of PPA increase. It is concluded that %PPA addition will enhance the performance of the Iraqi asphalt pavement and the mixture will be more rutting resistant, especially in high-temperature weather.
The aim of this work is to investigate the effect of soil corrosion on the critical buckling load of circular columns made of 2014-T4 aluminum alloy. In this work, 24 specimens were used and buried in the soil for 120 days. The samples divided into two groups (12 columns with corrosion before shot penning (SP) and ultrasonic impact treatment (UIT), and 12 columns with corrosion after combined surface treatments (SP+UIT)). The experimental1results revealed1that the corrosion negatively1affects the mechanical properties1of the material, and the1reduction percentage (R%) for1ultimate tensile strength (UTS) and1yield strength (YS) was (1.95% and 4.57%) respectively. After combined surface treatments (SP+UIT) for the corroded columns, the ultimate1tensile strength (UTS) and yield1strength (YS) were improved with (2.42%, and 2.87%) respectively. Perry-Robertson, Rankine, and ANSYS were used to estimate the critical buckling load (Pcr) and compare it with the experimental results. Rankine and Perry's formulas have been achieved a good agreement with the experimental without and with (1.5) factor of safety respectively. While ANSYS gave satisfactory prediction with a safety factor of (2.2, and 2.7) and (1.9, and 2.7) for long and intermediate columns before and after (SP+UIP) respectively.
Enhanced signal emission from nano (ESEN) coated titanium target over than that from normal untreated one was investigated. Four samples of Ti alloy were adjusted, the first sample was left untreated, the second and third samples were coated with plasma sputter at thicknesses of 35nm and 70nm, and the last sample was treated with a drop of colloidal Au nanoparticle solution prepared by laser ablation. The (ESEN) was monitored with Ti at 413.7 and 393.3 nm. It was obtained that the spectral emission from the nano-laser ablation had a greater improvement than that from the plasma sputter coating or bulk target. Enhancement factors were found up to ten folds, and show the spectroscopic line induced patterns by laser energies (100,150, and 200mJ) from the alloy with and without gold.
The interest in the Eye-tracking technology field dramatically grew up in the last two decades for different purposes and applications like keeping the focus of where the person is looking, how his pupils and irises are reacting for a variety of actions, etc. The resulted data can deliver an extraordinary amount of information about the user when it's interlocked through advanced data analysis systems, it may show information concerned with the user’s age, gender, biometric identity, interests, etc. This paper is concerned about eye motion tracking as an unadulterated tool for different applications in any field required. The improvements in this area of artificial intelligence (AI), machine learning (ML), and deep learning (DL) with eye-tracking techniques allow large opportunities to develop algorithms and applications. In this paper number of models were proposed based on Convolutional neural network (CNN) have been designed, and then the most powerful and accurate model was chosen. The dataset used for the training process (for 16 screen points) consists of 2800 training images and 800 test images (with an average of 175 training images and 50 test images for each spot on the screen of the 16 spots), and it can be collected by the user of any application based on this model. The highest accuracy achieved by the best model was (91.25%) and the minimum loss was (0.23%). The best model consists of (11) layers (4 convolutions, 4 Max pooling, and 3 Dense). Python 3.7 was used to implement the algorithms, KERAS framework for the deep learning algorithms, Visual studio code as an Integrated Development Environment (IDE), and Anaconda navigator for downloading the different libraries. The model was trained with data that can be gathered using cameras of laptops or PCs and without the necessity of special and expensive equipment, also It can be trained for any single eye, depending on application requirements.
Hot mix asphalt embedded on "Reclaimed asphalt pavement"(RAP) has the advantages of high technology. Moisture damage is a concern in these mixtures at all service temperatures. Therefore, the performance of this mixture against moisture at all service temperatures was considered a target of this research study. In this way, the effects of humidity on the performance of varieties were investigated using experimental methods including tensile strength ratio (TSR). In the framework of this study, Four different ratios of RAP for each of the surface and bonding layers (10%, 15%, 20%, 25%) and (30,40,50,60)% were added to the hot asphalt mix (HMA) for the two layers respectively to study and find the content Optimal RAP for both layers RAP through Marshall stability and hygroscopic resistance of asphalt mixtures through moisture damage is examined. The ratio (TSR) of the mixtures containing the optimal RAP content is compared with the asphalt mixture without RAP for three fillers and for both layers. The results showed a slight decrease in the tensile strength of the (HMA) that does not contain RAP compared to the asphalt control mixtures containing the reclaimed pavement, where it was found that the percentages were slightly higher and still higher than 80%. The results indicate that in general, Although there are old materials in the hot asphalt mix (HMA) produced from RAP, which include aggregates and bitumen binder surrounding the aggregate particles, the performance of these mixtures and integrations against moisture damage. Because it contains this, it can have results with “hot asphalt mixtures” containing RAP for areas with damage without worry in addition to good natural curbs.
Today, our cities are facing a host of challenges to accomplish the quality of life or their inhabitants. On the one hand, city planners and architects seek to preserve heritage, habits, and city peculiarities. On the other hand, it is necessary that the city is kept abreast of the rapid changes in Information and Communications Technology (ICT), Internet of Things (IoT), Artificial Intelligence (AI) and smart city concept. In Baghdad, it could be observed that there are several activities based on community initiatives, awareness campaigns, and initiatives which are self-funding from youth or funding from NGOs, and INGOs. How can we invest in such initiatives to achieve a smart city, emphasizing that the city is for the people, not a city of things? As we know that smart cities have six factors: smart (economy, governance, environment, people, mobility, and living)._x000D_ This paper assumes that smart communities are the seventh factor of smart cities factors which could play an essential role to apply the smartness in Baghdad. In this case, it will help to achieve making decisions and a feedback evaluation system will be subject to transparency, openness, vitality, and sustainability because it will stem from the community and ensure the sustainability in a smart city.
In this study, the mechanical properties of an epoxy, unidirectional woven carbon and fiberglass composite were investigated experimentally. ASTM used for preparing the composite specimen. Different ranges of mixing ratios of woven carbon and fiberglass with epoxy are studied. Tensile, impact and bending test are carried out to investigate the mechanical properties for produced new composites. After testing the mechanical properties of the specimens, it is noted that adding of unidirectional woven carbon layers will leads to strengthens the samples. The mechanical properties of woven carbon composite are far superior to those of woven carbon composite with fiberglass.
The main purpose of this paper is to design a robust second order sliding mode controller that can deal with uncertain nonlinear systems. This controller can keep the main advantages of the first order sliding mode controller, such as the ability to make the system asymptotically stable by forcing the error and its derivatives to have a zero value, the simplicity in the operation, and the robustness in the existence of perturbations. In spite of the features that characterize the first order sliding mode controller (1 SMC), it still suffers from the unwanted phenomenon “chattering”, which originates from a discontinuous control part (sign function). In this context, saturation function can be used instead of sign function to reduce this problematic chattering. Different from the saturation function method, the second order sliding mode controller can be used to overcome the chattering; suffered by the first order sliding mode controller and to retain the stability and performance of the system. In this paper, the twisting and the super twisting second-order algorithms of the sliding mode controller were used, and their results were compared with the first order sliding mode controller. So, this subject focused on the chattering problem who suffers from it the 1 SMC and try to reduce it by using the 2 SMC, the uncertain pendulum system was adopted in this work for the purpose of checking the three controllers. The simulations results showed that the second order sliding mode controller has the ability to reduce both the chattering magnitude and the steady state error and achieve an asymptotically stable system. The results were obtained by using MATLAB programming.
Laser annealing represents a powerful method for tailoring the properties of silver nanofilms on quartz substrates, offering advantages in terms of precision, scalability, and functionalization. Continued research efforts are expected to deepen our understanding and broaden the applications of this promising technology in diverse fields. In this work, laser annealing of silver nanofilms deposited on quartz substrates was performed and investigated. RF CO2 laser of variable power in the range 1–20 W with beam quality of 1.1 was used to anneal silver nanofilms. AFM analysis emphasized that nanocrystal sizes of 60 nm were obtained for silver nanofilms. Furthermore, the optimum absorbance peak occurred at about 449 nm for smaller film thickness. Thermal simulation and analysis of the annealing process were also conducted using COMSOL Multiphysics software. It was observed that optimal temperature of 729 K was achieved when 10 W laser power and 2 mm/s scanning speed were used to anneal 20 nm silver film thickness. Design of expert analysis was also used to better understand the laser annealing process of silver nanofilms since convolution of several process parameters affect the process output.
In this research, we investigate the nonlinear vibration of functionally graded carbon nanotubes (FG-CNTs) for simply supported sandwich cylindrical panels. The sandwich consisting of three layers formed of (FG-CNTs) and isotropic material as (CNT, ALMINUME, CNT). Mechanical properties of the sandwich media are acquired according to a re?ned rule of blend approach. The governing equations were derived using a first-order deformation theory (FOSDT). Four kinds of carbon nanotubes of sandwich cylindrical panels were analyzed. The volume fraction of CNTs is varied. The properties of nonlinear responses and free vibration are studied. The numerical approach employs the fourth-order Runge-Kutta and Galerkine procedure. Which conducted for the dynamic analysis of the panels to present the natural frequencies and non-linear dynamic response expression. The results show that; the natural frequencies and the nonlinear vibration amplitude decrease with the volume fraction and thickness ratio increase. The nonlinear vibration amplitude response increases when increasing the excitation force. The initial imperfection and the elastic foundation have a minor impact on the nonlinear vibration response of the panel. The Pasternak Foundation has a larger impact than the Winkler foundation. The structure formed of FG-CNT present an excellent choice for high-performance of engineering applications.
Additionally, it has been demonstrated that osseointegrated implantation offers superior proprioception and control over the prosthesis, enabling more natural movement and improved functional results. Additionally, it lowers the chance of falling and increases energy transfer efficiency, making it simpler for amputees to engage in physical activity. Furthermore, as compared to conventional socket prosthesis attachment, osseointegrated implantation has been linked to higher patient satisfaction and quality of life._x000D_ It is crucial to remember that osseointegration is a surgical operation with risks including infection and implant failure. Additionally, for effective implantation, it needs a specific amount and quality of bone, which may restrict its usage in some individuals. Furthermore, osseointegrated implantation could be more expensive than conventional socket prosthetics._x000D_ Understanding the efficacy and safety of this method requires research on complication rates and outcome metrics in patients having osseointegrated prosthesis implantation. You may acquire information on things like infection rates, implant failure, patient satisfaction, and functional results by studying original research papers. Clinical decision-making can then be improved with the use of this information._x000D_ In transfemoral amputees, osseointegration has showed promise as a powerful substitute for socket prostheses. A growing corpus of research has shown that osseointegrated implantation provides advantages in terms of increasing mobility, decreasing discomfort, and improving general quality of life. The efficiency of osseointegration for transtibial and upper extremity implants has received little attention._x000D_ Minor soft tissue infections are the most frequent consequences, although they are manageable with the right treatment and monitoring. To further reduce the risk of problems and improve the overall success of osseointegrated implantation, research and development are ongoingly focused on enhancing surgical methods and implant design._x000D_ Although osseointegration has a lot of potential, not all amputees may be good candidates for it. Considerations for osseointegrated implantation must take into consideration elements including the degree and nature of the amputation, the quality and density of the bone, and the desires of the patient.
Hydrogels are among the most versatile material classes used in biomedical applications. The material is of considerable interest in various fields of medicine due to its excellent features, such as high-water content, biocompatibility, and adjustable mechanical properties. The highlighted study thoroughly reviews Schiff-base thiadiazole-modified hydrogels as a novel functional material class, emphasizing their applicability in medical science. The addition of the Schiff-base and free thiazole groups to the hydrogel matrix introduces new antimicrobial activity, drug delivery, and bioadhesive attributes. An elaborate description of the methods employed to copolymerize thermoresponsive hydrogels with carbazole of thiadiazole as a binding group through free radical polymerization and visible light initiation is given under the first step of this general approach. The section on these hydrogels' physical and chemical properties was then added with a bias on morphological characterization, water uptake studies, and mechanical properties of the materials. After that, the discussion on more applications commenced, and among these, the following sections study them in the field of life-saving biomedical devices such as wound healing, tissue engineering, delivery of drugs, and biosensing prepared biosensing. A key emphasis is given to those interaction modes between Schiff-base thiadiazole groups and the biological systems that fulfil the hydrogels' healing mechanisms. These interaction modes, which include [specific modes], play a crucial role in the hydrogels' healing mechanism. The mentioned scholarship, in addition, dwells on the issues and barriers of such materials and gives thorough and valid judgements about the present and future of the matter. This review and the hard evaluation provide a thorough insight into Schiff-base thiadiazole-modified hydrogels' transformative impacts across the entire biomedicine area. A new approach is achieved by this review, in which the audience is made conscious and fully informed by presenting the most recent discoveries concerning the potential of Schiff-base thiadiazole-modified hydrogels to bring about innovative biomedical applications.
The research includes studying the mechanical properties of BNTN/PAM nanocomposites under static and dynamic conditions. The BNTN/PAM nanocomposites were prepared with different weight fractions (0, 20%, 40%, 50% and 60%) by utilizing ball milling technique. Tensile strength, Charpy impact and Shore A hardness were performed to verify any improvements in these mechanical properties of nanocomposites. The results showed significant improvements in tensile, Charpy impact, Shore A hardness properties of nanocomposites at 50% weight fraction by approximately 335%, 1422%, 63% respectively. These results started decreasing after addition of 60% of nanoclays content to PAM composites. This mechanism indicates that the percentage of weight content of BNTN could affect the mechanical properties of nanocomposites.
Numerical analysis of the performance of reinforced concrete (RC) deep beam subjected to static and fixed-point pulsating loading at the midpoint has been investigated. Three-dimensional nonlinear finite element model using the Strut and Tie approach was adopted. The damage level under the influence of the applied fixed pulsating loading is higher than the static applied loading, hence early crack was observed because of the stepwise loading in the form of vibration. Although the Strut and Tie approach gave a good estimation of the resistance capacity of the beam, the beam undergo high shear damage when subjected to these two types of loading. Material strength properties, applied loadings and cross-sections adopted are some of the factors that affect the performance of the deep beam.
Fused deposition modeling (FDM) is a commonly used 3D printing technique that involves heating, extruding, and depositing thermoplastic polymer filaments. The quality of FDM components is greatly influenced by the chosen processing settings. In this study, the Taguchi technique and artificial neural network were employed to predict the ultimate tensile strength of FDM components and establish a mathematical model. The mechanical properties of ABS were analyzed by varying parameters such as layer thickness, printing speed, direction angle, number of parameters, and nozzle temperature at five different levels. FDM 3D printers were used to fabricate samples for testing, following the ASTM-D638 standards, using the Taguchi orthogonal array experimental design method to set the process parameters. The results indicated that the printing process factors had a significant impact on tensile strength, with test values ranging from 31 to 38 MPa. The neural network achieved a maximum error of 5.518% when predicting tensile strength values, while the analytical model exhibited an error of 19.376%.
This paper displays the improvement of Graphical User Interface programming for sizing principle segment in Stand-Alone PV system and PV- Diesel hybrid power system based on Iraq conditions. The solar system software is a tool depends on the input data by the user to give correct results on the basis of what has been introduced. Therefore, this software tool Includes products (PV modules, charge controller, inverter, battery and diesel generator) which can be obtained from the market with their detail. This software presents a guideline for photovoltaic system integrator to match the load requirement to design the effective size of components and system configuration, in hybrid PV–Diesel system. The ratio of photovoltaic solar energy to diesel generators is introduced by considering the contribution of hybrid system energy.
In this paper, the H-infinity Sliding Mode Control (HSMC) is designed to produce a new dynamic output feedback controller for trajectory tracking of the nonlinear human swing leg system. The human swing leg system represents the support of human leg or the humanoid robot leg which is usually modeled as a double pendulum. The thigh and shank of a human leg is represented by two pendulum links and the hip joint will connect the upper body to the thigh and the knee joint will connect the thigh to the shank. The external torques (servo motors) are applied at the hip and knee joints to move the muscles of thigh and shank. The results show that the HSMC can robustly stabilize the system and achieve a desirable time response specification better than if only H-infinity or SMC is used. This controller achieves the following specifications: sec, for hip joint and sec, for knee joint.
Natural convection air heat transfer and fluid movement currents around a hot circular cylinder inside an inclined triangular enclosure has been analyzed experimentally. Three different sizes of an enclosure with a long side of 20, 25, and 30 cm, the thickness of 1 mm, and depth of 50 cm were used in the present work to give three radius ratios. The effect of Rayleigh number, radius ratio, the rotation angle of triangle enclosure, and the inclination angle of the apparatus with horizontal axis ? on the heat transfer process was investigated. The ranges of these parameters were: Rayleigh number from 5×106 to 2.5×108, radius ratio (0.345, 0.455, and 0.618), rotation angle (0o, 45o, and 90o), and inclination angle (0o, 45o and 90o). The results show that the heat transfer rates increase with increase in Rayleigh number and as the rotation angle of enclosure is changed from 0o to 90o. Moreover, the heat transfer rate increases linearly with Rayleigh number at higher radius at rotation angle 0o, 90o only. While, it increases slightly with Rayleigh number at rotation angle 45o. Additionally, the higher heat transfer rates occur at vertical position of enclosure inclination angle 90o and rotation angle 0o (the base of triangle at the bottom) and it decreases as inclination angle deviates from 90o to 0o. This behavior is reverse completely at higher radius ratio 0.618. Empirical correlations for the average Nusselt number has been found to depend on Rayleigh number., radius ratio, rotation angle and inclination angle.
Cascade single mode-No Core - single mode fiber structure (SNS) optical filters have garnered a lot of interest as dependable optical devices. These devices' simplicity, compactness, affordability, all-fiber design, low transmission loss, and ability to continuously adjust the laser wavelength at a particular spectral range contribute to their dependability. The operation's foundation is multimode interference (MMI) and self-image phenomena. SNS filter based on optimized 4th self-imaging condition for different NCF- Specifications was theoretically optimized a tunable filter based on a cascade single mode-no core-single mode (SNS) fiber structure encircled by Ferrofluid was experimentally investigated. The findings indicate that reducing the NCF diameter can enhance the filter's tunability. device has applications in fiber laser technology, spectroscopy, and optical communication.
In Urban cities, services are supported by intelligent applications and are connected to each other through ad hoc networks. Any service can be operated using a compatible of an Internet of Things (IoT) technology. This study focuses on the transportation service and finding a non-cost solution to solve the crossroads congestion that affected people time and money. The Wireless Sensor Networks (WSNs) that are planted on the roads can help in monitoring the roads situation by collecting their data and send them through wireless communication to a traffic management center. In this work two phases of time are considered for a crowded area. Low-cost components are suggested to solve the congestion at the cross roads without the need for reconstruct the roads. IoT device such as smart phone can be wirelessly connected to the Traffic Management Center (TMC), which can analyze the incoming data from WSN and send back the calculated time to the police officer to control the green light long and overcome the standard time installed for all directions. The main idea is to solve the congestion problem in real time by extending the time long of the green traffic light for the road direction with the highest vehicle density. The suggested algorithm was operated on a dataset of 6 days and for the time phase from 7:00-10:00am.
The indemnification of uncertainty and disturbance which is added to non-linear systems by an Integral Sliding Mode Controller (ISMC) design. the key target of this paper is designing a sturdy controller to observe the performance of a 2-link robot. The nonlinearity in mechanical systems is a shared issue that the researchers are facing in formulating control systems for it. The best solution to this problem is a design Sliding Mode Controller (SMC) for controlling a nonlinear system. In the current paper, 2-link robot is studied which suffering from disturbances and parameter uncertainty and coulomb friction as additional to friction inertia of the system for each link. firstly, Classical Sliding Mode Controller (CSMC) is designed and then Integral Sliding Mode Controller (ISMC). As known, CSMC includes two phases: reaching phase and sliding phase. SMC is suffering from the known phenomenon as "chattering" which is supposed as a critical case and unsuitable characteristic. chattering is described as a curvy movement span the switching surface. In the current study, the chattering is attenuated by employing a saturation function alternative of a sign function. Although SMC can be considered as a good way of controlling nonlinear systems. Where it continues to suffer from the long settling time as undesired features. ISMC is a good method can be employed for reducing the settling time and controlling a nonlinear system. ISMC is easy, robust execution and supposes as an active and strong technique. The most significant advantage in ISMC designing, the reaching phase is canceled that considered a major part of designing classical SMC. The 2 link Robot system was used for proving the performance of CSMC and ISMC algorithms. The outcomes received from the simulations utilizing the ISMC and CSMC which fulfilled asymptotic stability for the system. In comparative between CSMC and ISMC. ISMC is better than CSMC in the good performance of tracking the desired position with less time. Finally, MATLAB2019a software package has relied upon this work.
In today's world, Urinary Tract disorders such as obstructions whatever the causes (stricture, stones), are prevalent and can be extremely dangerous and painful for individuals. One of the most important instruments in the Urological sector for a variety of clinical diseases is the Ureteral stent, a minimally invasive surgical tool for relieving blockages and facilitating kidney-to-Bladder drainage. This review addressed the problems of biofilm formation and polymers currently available for use as new biomaterials in new Ureteral stent designs, providing a comprehensive update on recent developments in stent development. It also evaluated the various biomaterials that found application as Ureteral stents in relation to various issues such as encrustation, bacterial colonization, urinary tract infections, and related clinical issues. This study concluded with a discussion of biomaterials' potential applications and the design in the Urinary Tract.
In the past few years, all over the world, crime against children has been on the rise, and parents always worry about their children whenever they are outside. For this reason, tracking and monitoring children have become a considerable necessity. This paper presents an outdoor IoT tracking system which consists of a child module and a parent module. The child module monitors the child location in real time and sends the information to a database in the cloud which forwards it to the parent module (represented as a mobile application). This information is shown in the application as a location on Google maps. The mobile application is designed for this purpose in addition to a number of extra functions. A Raspberry Pi Zero Wireless is used with a GSM/GPS module on shield to provide mobile communication, internet and to determine location. Implementation results for the suggested system are provided which shows that when the child leaves a pre-set safe area, a warring message pops up on the parent’s mobile and a path from the current parent location to the child location is shown on a map.
Researches are now being conducted on redesign as well as micro ergonomic interventions. Most micro-surgical tool designs concentrate on the manipulation of targeted tissue instead of the surgeon's hand, and this presents a new research opportunity for better fitting the equipment to the surgeon's hand. So the objective is to examine the advancements made in the last few years and provide a framework for ergonomic intervention framework regarding manufacturing systems. With the use of words like ergonomic design, intervention, and evaluation," the titles and abstracts of ergonomics publications were filtered to find relevant research. The paper describes the way that the concept of micro-ergonomics can enhance the design of the micro-instruments. Finally, an application of a new surgical instrument is stated as a pen needle holder designed by SOLIDWORK 22 which creating a wide range of possible uses for futuristic technology. In future, neurosurgical equipment design will incorporate concepts from surgical tool design together with penization, microergonomics, and electronics.
Millimeter Wave (mmWave) Massive Multiple Input Multiple Out (MIMO) system is a key technology for future wireless transmission. The system's architecture can differ based on the type of Analog-to-Digital Converters (ADCs) used at the receiver, whether they are all low-resolution or a mix of different resolutions (Mixed-ADCs). Mixed-ADCs is a promising solution to achieve better performance than low-resolution ADC-only architectures by leveraging high-resolution ADCs to capture critical signal components while maintaining energy efficiency through low-resolution ADCs. In this paper, the problem of channel estimation for this system architecture is taken into consideration. A novel compressive-sensing based algorithm, that is called Approximate Conjugate Gradient Pursuit (ACGP), is proposed to estimate the channel coefficients. The performance of the proposed algorithm is investigated under varying system parameters, including different Signal-to-Noise Ratios (SNR), Radio Frequency (RF) chains, ADC resolutions, and numbers of observation frames. Matlab software was used to perform numerical simulations. The results demonstrated that mixed-ADCs architecture outperforms low resolutions only in performance. It was found that ACGP achieves lower Minimum Mean Squared Error (MMSE) compared to Orthogonal Matching Pursuit (OMP) and Least Square (LS), particularly in low SNR conditions showcasing its robustness and efficiency in signal reconstruction, achieving an average enhancement of 30% to 50% at moderate SNR levels. While OMP exhibited faster computation times under various number of observation frames, ACGP maintained stable computational performance, with a slight increase in computation time. For applications where accurate channel estimation is required under noisy environment, the proposed algorithm is an effective choice to meet such requirements.
In this work, for ultra-wideband (UWB) applications, a passive filter antenna with edge chamfering is investigated in this paper. The performance of an optimized UWB antenna design that achieves an advanced fractional impedance bandwidth of 102% is confirmed by simulation and experimentation. The performance of the antenna is improved by integrating a lowpass filter (LPF) into the fed line, which suppresses high-frequency radiation with a central frequency of 3.5 GHz (WiMAX), the UWB antenna has been transformed into a narrowband antenna, offering a 43.7% fractional bandwidth that spans the frequency range from 2.7 GHz to 3.9 GHz. A stepped impedance transmission line and an extended fractal H-shaped structure integrated in the microstrip feedline make up the filtering network. Using CST Microwave Studio (CST MWS), key performance parameters such as the radiation patterns, efficiency, gain, and reflection coefficient (S11) were examined. In its prototype, the antenna reduces its size by 5% and is made on a FR4 substrate with a permittivity coefficient of 4.3 and a loss tangent of 0.02. A maximum gain of 1.7 dBi and a peak efficiency of 78% at the center frequency were verified experimentally. The center frequency was verified experimentally. The tiny antenna, which measures 0.30λ₀ × 0.37λ₀ × 0.008λ₀, performs well and is appropriate for UWB applications. The design makes a significant addition to the realm of UWB technology by incorporating elements that improve its ability to adapt.
Regaining the activities of daily living after stroke and spinal cord injury requires repetitive and intensive tasks, meaning that rehabilitation therapy should be treated with a long duration. Thus, the need for rehabilitation devices based home is of most importance to increase the rehabilitation process and provide more comfortability for patients. This paper focuses on implementing and construction of a three degree of freedom (DOF) (flexion/extension, adduction/abduction, and pronation/supination), low cost, lightweight, and portable robotic exoskeleton for wrist-forearm rehabilitation. SolidWorks software program and 3D printer technology are used to model and construct the proposed robotic exoskeleton structure. In addition, the anthropometric parameters of the normal human lower arm are considered for this exoskeleton to provide a range of motion (ROM) and velocity for the links, joints, which matches with the anatomical structure of human and also to avoid the excesses motions over the normal range. The exoskeleton is constructed by a 3D printer utilizing polylactic acid (PLA) plastic material. The proposed implementing structure of the robotic exoskeleton shows comfortable, lightweight, simple and economic as well.
Over the last several years, additive manufacturing (AM), sometimes known as "3D printing", has seen remarkable expansion due to mechatronics and materials science advancements. Fused filament deposition (FDM) production is the predominant technology in additive manufacturing (AM) because of its cost-effectiveness in operational and material expenses. Nevertheless, the materials often used for this technique are pristine thermoplastics. Unsuccessful printing and throwaway prototypes generate a significant quantity of trash. Utilizing green and sustainable products is crucial to minimize the environmental effects. Recycled, bio-based, and mixed recycled materials provide a promising solution for 3D printing. The absence of comprehension about the interlayer adhesion process and material degradation in FDM printing has presented a significant obstacle for these environmentally friendly materials. This study comprehensively examines many materials used for FDM three-dimensional printing filaments, including recycled, bio-based, and mixed materials. The merits and drawbacks of thermoplastics and their composites were deliberated over. This evaluation is a comprehensive guide for engineers and researchers in selecting appropriate materials for three-dimensional printing. Three-dimensional printed objects have worse mechanical characteristics in comparison to injection molded materials.
This research focuses on enhancing the diagnostic power of the slit lamp, a fundamental ophthalmic instrument, by replacing its traditional halogen light source with a cutting-edge white laser. The objective of this modification is to significantly improve the brightness, intensity, and color accuracy, which are crucial for distinguishing fine ocular details during eye examinations. White laser technology offers a more stable, energy-efficient light source with reduced maintenance needs, making it a valuable upgrade over conventional systems. As part of this redesign, the optical system will be optimized with new filters, lenses, and heat management techniques to accommodate the white laser. Additionally, integrating a high-resolution digital camera with the enhanced illumination system is expected to provide sharper, more accurate imaging for better diagnosis. The anticipated outcome is a transformative improvement in ocular diagnostics, leading to earlier and more precise detection of eye conditions. This advancement holds promise for both patients, through better care, and ophthalmologists, through increased diagnostic efficiency. Challenges in implementation and potential solutions are also considered.
In this work, environmentally friendly zinc oxide nanoparticles was produced using sustainable green technology. With several loading amounts, such as 5%, 10%, 50%, and 100%, the banana peel extract was utilized as a capping agent. This was followed by calcinations at 400 ºC for 3 h in a muffle furnace. To evaluate the physical and chemical change of the synthesized nanoparticles, XRD, FTIR, UV-VIS and SEM/EDAX was used. The characterization results reveald that the all the green synthesized ZnO NPs samples strongly supports the well-crystallinity with high phase purity. The average crystallite size of the prepared samples was calculated using Debye-Scherer's formula and the results shows that with an increase in extract amount, the average crystallite size was shrinking. The FTIR result verified the successful chemical reaction between zinc salt and banana peel extract. The UV-VIS results showed the effect of size quantisization phenomena at 100% extract adding. Finally, the SEM images for all the prepared samples confirm the spherical shape.
As internet network developed rapidly in the past ten years, and its operating environment is constantly changing along with the development of computer and communication technology, the congestion problem has become more and more serious. Since TCP is the primary protocol for transport layers on the internet, the data transmitted via the transport protocol utilizes Vegas Transmission Control Protocol (TCP) as the congestion control algorithm, where it uses increasing in delay round trip time (RTT) as a signal of network congestion. However, this congestion control algorithm will attempt to fill network buffer, which causes an increase in (RTT) determined by Vegas, thereby reducing the congestion window, and making the transmission slower, Therefore Vegas has not been widely adopted on the Internet. In this paper, an improved algorithm called TCP Vegas-A is proposed consist of two parts: the first part is sending the congestion window used by the algorithm for congestion avoidance along with the TTL (Time To Live) mechanism that limits the lifetime of a packet in the network. While the second part of the algorithm is the priority-based packet sending strategy, and jitter is used as a congestion signal indication. The combination of the two is expected to improve the efficiency of congestion detection. A mathematical model is established, and the analysis of the model shows that the algorithm has better effects on controlling congestion and improving the network throughput, decreasing packet loss rate and increasing network utilization, the simulation is done using NS-2 network simulation platform environment and the results support the theoretical analysis.
A numerical study was performed of natural laminar convective heat transfer to its concentrated triangular enclosure around a horizontal circular cylinder. The air-filled enclosure kept the inner and outer cylinders at uniform temperatures. The Boussinesq density approximation to the momentum problem and the control volume approach iteratively resolved the governing equations to explain buoyancy. CFD results show that the velocity behavior increases by increasing Ra, so the stream lines becomes more sluggish and less uniform behavior and vortices gets less circulated pattern. The rotation angle ? has significant effect on vortices, at 90o gives the higher range of velocity zones of free convection with higher range. The thermal boundary layer seems to be larger in rr=0.455 as compared with rr=0.345 and decreases by increasing ?. The larger variation of isotherms and thermal boundary layer appears at lower ? because the higher heat transfer rate occurs at higher ? and becomes maximum at 90o. Eight correlations of average Nusselt number have been deduced as a function of Rayleigh number for the taken values of aspect ratio and enclosure angles of rotation and inclination.
The process of increasing the heat transfer coefficient, resulting in enhancing system efficiency, is known as heat transfer enhancement. Enhancing heat transport is both economically beneficial and a considerable energy conservation problem. To improve heat transfer, many passive components are utilized within tubes, including wire plugs, enhanced surfaces, rough edges, twisted tape inserts, and liquid additives. This study evaluated twisted tape inserts, which are highly effective passive devices. Considering its numerous advantages, such as effortless maintenance, uncomplicated operation, and straightforward production. The twisted tape inserts within the tube generated a vortex and swirling flow. The interior convective heat transfer process is significantly improved. A summary of various twisting tape additives that can boost performance.
The transportation cost problem of solid waste presents the biggest part of the budget allocated by municipalities for SWM. So, there is no comprehensive plan to address transport routes optimization problems in SWM that including the transfer of solid waste from transfer stations to final landfill sites. Therefore, the aim of the study finding a scientific method to solve the transportation problem of solid waste transport suitable Baghdad city that tries to find feasible solutions that ensure reducing total transport costs and leads to an effective solid waste management system. In this research, a new methodology has been developed to select the optimal transport routs of SWM in Baghdad city which involves determining the best-supposed scenario. the proposed methodology includes integration of Global Positioning System (GPS) technologies with Network Analysis model (NA). Therefore, this work provides an advanced framework of decision-makers for analysis and simulation of the optimal transport routs problem related to SWM. Applying these modeling tools to select the scenario that can provide economic benefits by minimizing travel time, travel distance and reduction of total transportation costs. The Results of work implementation show that all solutions that include current state S1 and suggested scenarios have been evaluated. The scenarios generated include (S2, S3) by applying the proposed technique for analyzed and identified the optimal routes. The solutions of scenario S2, specified with two landfill sites while scenarios S3 specified with four landfill sites. Finally, this work shows the Scenario S3 is the best scenario of the solution, that include applied GPS and Network Analysis for four landfill sites.
With the occurrence of pathological disorders in some people or aging, metabolic energy consumption begins significantly due to the weakness of the peripheral muscles and the increase in body fat with time, which aggravates the issues for this type of people, causing the rest hours extremely lengthy and consequently may produce heart or arterial diseases and elevate the mortality rate. Regarding the significance of the matter, this study examines a number of previous researches that featured several approaches to energy calculation and strategies for lowering energy consumption through the use of various external assistance devices, such as exosuits or exoskeletons, to assist people in carrying out their everyday tasks. And additionally discussed musculoskeletal simulation employs a variety of programs, especially OpenSim, which enables users to build models of musculoskeletal structures and produce dynamic movement simulations. According to the research findings, exoskeletons and other assistive technology can successfully lower the cost of metabolic energy to varying extents, depending on the device's weight, placement within the body, and whether it is active, semi-active, or inactive. In the future, the work to design and simulate a semi-active torsional ankle-foot exoskeleton with a specialized mechanism aimed to minimize metabolic energy.