Articles in This Issue
Abstract
Construction joints are separations between successive concrete pours. They are critical in the building of large concrete structures, since these structures cannot be cast in a single pour. Self-consolidation concrete is a relatively new kind of concrete that is considered suitable for a wide range of construction applications, especially those needing a high early resistance. Certain findings from earlier experimental tests were adopted and analyzed using finite element analysis. ANSYS program was used to analyze the impact of utilizing high strength concrete (fc') and the secondary reinforcement ratio (ρv) on the behavior of reinforced self-consolidating concrete beams having a horizontal construction joint. Nine beams analyzed in this study have the same dimensions (150×180×1200) mm (width× height ×length). Between the two supports, the clear span was 1100 mm. Two-point loads were applied to the simply supported beams during testing. One of the beams acts as a control beam (without a construction joint) and the remaining beams were with horizontal construction joint in the tension zone. The ultimate loads obtained analytically vary by between 3.1% and 7.8 % from those found experimentally. The presence of the horizontal construction joints made the beam less stiff. Utilizing a 70 MPa high strength concrete resulted in a 47.4 % in ultimate load over the experimental value for regular strength concrete (28 MPa). Increasing the ratio of secondary reinforcement (0.01229 to 0.049) resulted in a 10.3% increase in ultimate load magnitude, while decreasing the ratio of secondary reinforcement (0.01229 to 0.0025) with spanning the spacing between stirrups led to a reduction in ultimate load magnitude by 55.8%.
Abstract
A tack coat is a minimal coating of asphalt cement, cut-back asphalt, or asphalt emulsion to an existing pavement surface between layers to guarantee proper bonding between the two layers and longitudinal and transverse joints. Numerous researchers have assessed interlayer adhesion employing failure-mode behavior tests, such as pull-off, direct shear, and torsion testing. This study aims to quantify the best tensile resistance obtained using three types of cutback asphalt (RC70, RC800 modified with polymer 4.5% & MC70). All are applied on concrete surfaces at a rate of 0.5 L/m². The Proceq DYNA Z16 pull–off tester is used to measure the tensile strength at a rate of 0.25 kN/s. It is found that the average tensile strength of the tack coat materials is (0.319, 0.138, 0.028) MPa, respectively. It is concluded that RC70 has the maximum tensile strength. Also, the different types of solvent affect adhesion strengths; RC70 was Prepared using gasoline, while MC70 used petroleum. Gasoline has greater volatility and thus increased adhesion. Failure strength modes of interior bonding varied between cohesive failure adhesive and adhesive failure.
Abstract
In order to avoid losing sense of sight in a large portion of the working population, Diabetic Retinopathy (DR) identification during broad examination for diabetes is crucial. To prevent blindness in the future, early illness detection and measurement of disease development are essential. DR is diagnosed through medical image analysis. After the success of Deep Learning (DL) in other applications in the real world, it is considered a vital tool for upcoming health sector applications, providing solutions with accurate results for medical image analysis. This review provides a comprehensive survey of the state-of-the-art DL models for DR detection and grading using retinal fundus photography. This review thoroughly examined and summarized 81 relevant publications that were published through IEEE Xplore, Web of Science, PubMed, and Scopus between 2018 and 2023 based on the available database with binary or multiclass CNN classification models as well as the main preprocessing techniques. According to the findings of this review, transfer learning has proven to be an excellent technique for addressing the problems of limited resources for data for DR analysis. CNN models having tens or hundreds of layers are the most frequently utilized frameworks for DR classification. The most extensively utilized datasets for DR categorization are Aptos 2019 and EyePACS. Although DL has attained or surpassed human-level DR classification accuracy, there is still more work to be done in real-world clinical procedures.
Abstract
The purpose of this research is to manufacture and test adjustable sockets for below-knee amputation. This article studies using the pnuematic–pads for adjustable sockets. The manufacturing of an adjustable socket with pneumatic pads goes through several stages: In the theoretical design of the adjustable socket, the suggested materials were studied for the pneumatic pads, tubes, and pneumatic pump which should be suitable for the suggested application. In the experimental work, using composite materials for manufacturing the socket consisting of perlon and resin to achieve the rigid shape and required flexibility for the prosthetic user with the pneumatic pads. After assembling the adjustable socket parts, the pneumatic pads, the pump and the tubes, the socket were tested for several times on the patient. In the last stage, the pressure between the socket and the residual limb was measured using F-socket, and it was found that the results were: anterior (160kPa), lateral (167kPa), posterior (153kPa) and medial (348kPa). By comparing these results with what was previously studied, the pressure between the socket and the residual limb is within the acceptable range. The design provides good suspension and more adaptability to the change in stump volume. A posative feedback was given by the patient who used the prosthetic patient for several days as a trial to measure its safety and comfortablty.
Abstract
Functionally graded material is one of the promising sectors of the material since because of the great ability to control with required product properties could be strongly used in biomedical applications exclusively in the implants sector, this review paper demonstrates briefly about the most prominent known manufacturing methods and focusing on the implants coated by FGM layer manufactured by using EPD method because the EPD has significant properties it could produce FGM layer in the Room temperature without depending on chemical reactions or heat adding, Biomedical application need highly accuracy when we deal with material that directly contact with human tissue because the heat effect could be change the biocompatibility properties and also the chemical reactions could make toxic effect on the produced implants, All these reasons make the EPD one of the favorable method for the FGM coated Implants. this paper will summarise and give the Gide line for the researcher about the most important substrate and suspension materials used in the EPD method and its application.
Abstract
Technically, medical imaging modalities are quantitative, qualitative, and semi-quantitative. Such modalities can generate meaningful and valuable quantitative and qualitative data. Correlating predictive outcomes with quantitative and qualitative data is a difficult process. Thanks to modern computational hardware and advanced machine learning algorithms, it is not a demanding job to perform predictive analysis by cultivating quantitative and qualitative data. Radiomics is a popular topic that studies quantitative data from medical images in order to obtain biologically meaningful information for diagnosis, prognosis, theragnosis, and decision support. Handcrafted radiomics is a process including features based on shape, pixel, and texture-related knowledge from medical scans. In the pursuit of advancing the field of radiomics, we have developed a cutting-edge radiomics training simulator, powered by MATLAB. This tool has been designed for those familiar with MATLAB, making it easy for them to transition into the fascinating world of radiomics. MATLAB's user-friendly interface and strong support in the engineering community provide an ideal platform for this simulator, ensuring aspiring radiomics learners have access to the resources they need for success. Throughout the paper, purpose, design details and methodology of the simulator are described.
Abstract
The current study presents the plasma cutting process of 2 mm thickness of AISI 1020 carbon steel. The experiment conducted by taking into the account the effect of two process parameters, including cutting current of 15 and 20 A with cutting speed in range of 500 - 4000 mm/min, on the kerf formation, microstructure and microhardness.The results showed that at low cutting current of 15 A the melting occurred at the workpiece surface without cutting action. Increase the current to 20 A led to full penetration of the workpiece material at low and high cutting speed, with kerf width between 1.26 mm and 1.1 mm for cutting speed of 500 mm/ min and 4000 mm/ min, respectively. The plasma arc cutting speed has a high impact on the heat-affected zone HAZ and microstructure development with coarse grains at the HAZ at low cutting speed of 500 mm/min and constant current of 20A, increase the plasma cutting speed led to decreasing the grain size. The microstructure of the HAZ exhibited a presence of perlite and ferrite with some martensite structure. The highest microhardness of the HAZ of 220.8 HV was found in the sample processed at 20 A current and high cutting speed of 4000 mm/ min. However, the minimum microhardness of the HAZ of 156.7 HV was found in the sample processed at 20 A current and low cutting speed of 500 mm/ min.
Abstract
A high-performance Mach-Zehnder interferometer (MZI) based all-optical switch using graphene on silicon nitride (Si3N4) is proposed and simulated. Graphene absorbs pump power (λ = 980 nm) on Si3N4 waveguide, generating heat. The heat affects the Si3N4 waveguide, causing a change in its refractive index due to thermo-optic effect. By tuning the probe phase (λ = 1550 nm) in the Si3N4 arm with graphene on top, all optical switching can then be carried out. An extinction ratio ranges of 13-25 dB and pump power range 20-270 mW. These findings demonstrate that our suggested configuration offers a useful integrated part for the creation of effective all-optical control devices on the insulator platform with a quick switching rate. Moreover, the suggested design might be able to achieve a wide bandwidth by utilizing an integrated MZI structure.
Abstract
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.
Abstract
Expansive soil poses significant challenges for civil engineers worldwide since it seriously affects the structures built upon it. This soil has a very active group of minerals called montmorillonite, which is responsible for the significant volume change it exhibits. For a number of years, chemical additives have been utilized to stabilize soil, with various levels of success. Soil stabilization has involved the use of a variety of additives, including cement, lime, polymers, salts, and combinations of these. However, lime is very often used for expansive soil stabilization as it improves the soil's mechanical properties. The effects of adding three percentages of lime (3%, 6%, and 9%) to expansive soil to improve its engineering properties are investigated through several tests. The laboratory tests consist of standard compaction, sieve analysis, atterberg limits, hydrometer, California bearing ratio, consolidation test, swelling potential, and specific gravity. The test results displayed that the plasticity index, liquid limit, swelling potential, and maximum dry density, specific gravity decreased using (3%, 6%, and 9%) lime. In contrast, the plastic limit, and optimum moisture content increased using (3%, 6%, and 9%) lime. The California bearing ratio is increased from (12.13% to 14.65%) by adding (9% L). The swelling index and compression index are decreased from (0.070 to 0.030) and from (0.581 to 0.193) respectively by adding (9% L). The swelling percentage is reduced from (18.77% to 6.03%) by adding (9% L).
Abstract
Quality control of riverbank roads is a vital part of the road construction and maintenance process and aims to ensure infrastructure quality, safety, and sustainability. This requires adherence to technical standards, constant auditing, and regular maintenance to maintain the condition of the roads and avoid potential problems. The first step in the quality control of roads is to test the efficiency of the subgrade soil. A geotechnical investigation of subgrade soil under river bank roads is carried out to evaluate the engineering properties of the soil and determine the soil’s ability to bear the loads resulting from vehicle movement and road traffic. This investigation includes analyzing soil samples and laboratory tests to determine soil properties and determine any improvements the soil needs to bear the loads. Soil samples were collected from Al-Kadhimiya Corniche Street. It was dried and subjected to laboratory tests, the soil in this study is classified as poorly graded sand (SP), GS 2.589, the shear strength parameters an internal friction angle of 33 degrees and cohesion of 0.5 kN/m2, and the results of the compaction test indicated that the optimal moisture content was 8.1%, with a maximum dry density was 18.24 kN/m3, CBR 26.04%, and chemical tests (SO3 0.222, pH 8.55, T.SS 0.891, CL 0.085). Software FAARFIELD was used to check pavement design, the thickness design was executed utilising a subgrade CBR value of 26.04%. The subgrade pavement thickness was determined to be 304mm in total. The results agree with the actual design of Al-Kadhimiya Corniche Street, which was recently maintained during the field investigation in 2023.
Abstract
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.
Abstract
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%.