2023 Cilt 28 Sayı 3

Permanent URI for this collectionhttps://hdl.handle.net/11452/41019

Browse

Now showing 1 - 8 of 8

Alternative lightweight composite facing members for reinforced soils
(Bursa Uludağ Üniversitesi, 2023-11-13) Evirgen, Burak; Tunaboyu, Onur; Büyük, Barış; Çil, Gizem Tuğçe
Steel reinforced concrete facing members, which are used to fix geosynthetic reinforcements working against tensile forces inside soils and to resist active lateral earth pressures, have certain disadvantages, such as massiveness and corrosion. In addition, the aforementioned conventional panels arenot economical since they frequently require maintenance and repair in terms of long-term stability. In thisstudy, the utility of alternative composite panels is evaluated with the various arrangement and type of fiberreinforcements and a typical foam concrete. Panel tests and three-point bending tests are realized to determine the experimental behavior of steel, carbon fiber (CFRP) and glass fiber reinforced (GFRP) specimens, as well as unreinforced examples. Although CFRP wrapped specimens cannot reach expectedlevels, samples with GFRP present favorable performance as well as being cheaper. Specimens with matGFRP enhance both strength and deformation capacities according to the results of axial and lateraldeformations under diagonal loading condition. In addition, chopped GFRP applied foam concret especimens have more strength in terms of bending test results, but CFRP reinforcements increase the irdisplacement capacity.
Development of a method for calculating loads on implants and prostheses used for the human skeleton
(Bursa Uludağ Üniversitesi, 2023-09-05) Tunc, Ismet Emircan; ŞEFKAT, GÜRSEL
The study proposes a novel computational approach for customizing sustainable knee disarticulation prostheses, aimed at improving the quality of life for users. A specialized calculation technique for assessing the loads and moments on the prosthesis was formulated, leveraging MATLAB for solving kinematic equations, Solidworks for motion analysis, and ANSYS Workbench for material and static analysis. The integration of these tools enabled the validation of the design and analytical outcomes. The kinematic solutions accounted for individual and prosthesis weights, analyzing linear and angular dynamics over a motion range pertinent to the prosthetic leg's function. Static analysis was executed to determine maximum force impact on the prosthesis. The study's results were conducive to identifying the most suitable prosthesis characteristics for individuals aged 20 to 80, with a height of 160-190 cm and a weight of 80-120 kg. The prosthetic design promoted ease of movement in activities requiring a range of motion, such as running and jumping. The prosthesis adapted swiftly to body movements, achieving readiness in approximately three seconds. The research underscores the importance of interdisciplinary collaboration between engineers and medical professionals to optimize the anatomical and kinematic aspects of prosthesis design.
Development of MNO2/PANI/SWCNT nanocomposite supercapacitor electrode and investigation of electrochemical performance
(Bursa Uludağ Üniversitesi, 2023-09-25) Özada, Çağatay; Ünal, Merve; ÖZER, HAKKI; YAZICI, MURAT
In this study, a manganese dioxide (MnO₂/polyaniline (PANI)/ single-walled carbon nanotube (SWCNT) nanocomposite electrode was prepared for pseudo-supercapacitors. To reduce the internal resistance of the electrode, increase the capacitance stability, and reduce the cost of single-walled carbon nanotubes, SWCNT was subjected to two-step acid etching. The purity of SWCNT was improved from ~95% to 99.98%. In addition, SWCNT was functionalized by this process. Thus, a nanocomposite was formed by coating PANI around SWCNT. MnO₂/PANI/SWCNT were synthesized using the hydrothermal method. Morphological, chemical and thermal analyses of the synthesized nanocomposite structure were carried out. In addition, X-ray diffraction (XRD) was used to determine the crystal structure. Electrochemical analyses were performed using a three-electrode system in a 1 M KOH electrolyte solution. Cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) measurements were performed. The capacitance of the nanocomposite electrode at 400 cycles was314 mF/cm², and the capacitance retention stability was calculated at 73.24%. The results showed that the capacitance stability was high, and the supercapacitor was sensitive to redox reactions.
Development of seamed compression socks and comparison with class i socks using existing mathematical models
(Bursa Uludağ Üniversitesi, 2023-09-18) Akçagün, Engin; Siddique, Hafiz; Yılmaz, Abdurrrahim
Compression therapy is an important method for treating venous diseases such as venous edema and venous hypertension. Regular compression therapy's main objective is to diminish leg swelling by controllingblood flow and avoiding the recurrence of reversible blood flow. Compression socks are often recommende das therapeutic garments. In this study, a seamed compression sock was developed using fabric with an interlockknit structure. Three other sock samples were produced by using circular knitting MERZ CC4 model machinefor comparison. The results demonstrate that the developed sock meets all the requirements of compression class I. Statistical analysis reveals that fabric parameters, particularly fabric weight, effectively explain compression pressure intensity according to the values of coefficient of determination, coefficient of correlation(r), and means sum of square errors (MSE). In this work, Laplace's Law and a few preexisting mathematicalmodels were used to calculate the compression pressure of both standard compression socks and socks withseams, with results that were essentially similar. The points of data are tightly clustered around line of regression, showing that there is little variation in the compression pressure for socks with seams.
Dyeing of silk in Edirne red color with madder
(Bursa Uludağ Üniversitesi, 2023-10-11) Yüce, İsmail; Becenen, Nilgün
Silk is a natural filament obtained from the Bombyx mori species of silkworm, with a fiber length of up to 3000 meters. During the Ottoman era in Edirne, sericulture and silk trade were important activities. To this end, silk factories, trade centers, and silk weaving schools were established, creating an important sourceof income for the people of Edirne. Edirne Red is a natural dye obtained from the Rubia Tinctorum L. plant and is part of the Ottoman Empire'sheritage. This dye is resistant to sunlight and washing. It has been used in Turkish carpets, as well as in silk andcotton fabrics.The aim of this study is to bring together the importance of Edirne Red and silk in Edirne's history. For this purpose, 100% silk fabrics were dyed using madder (Rubia Tinctorum L.) grown within the borders of Edirne province. The effects of dye ratios and auxiliary chemicals used on color and colorfastness were examinedduring the dyeing process. The color values of the fabrics were measured numerically in the CIEL*a*b* colorspace, and the washing and light fastness values of the dyed fabrics were also measured. Additionally, high-performance liquid chromatography (HPLC) analyses were performed on both the used madder and the dyedfabric. Based on the obtained data, the closest Edirne Red color was achieved by pre-mordanting fabric before dyeingand using ethanol as the dye solvent. Madder dye, successfully applied to silk fabrics under different conditions, has shown good results in terms of color yield and fastness properties.
The exploitation of titanium dioxide nanoparticles for improving the performance and emissions of biofuel-diesel blend-fuelled stationary diesel engine
(Bursa Uludağ Üniversitesi, 2023-09-23) Çakmak, Abdülvahap
In this research, the potential effects of titanium dioxide (TiO₂) nanoparticles on improving astationary diesel engine characteristic fuelled with a biofuel mixture-diesel blend (B25: 25% vol. biofuelmixture containing biodiesel, waste cooking oil and ethanol + 75% vol. diesel) are experimentallyinvestigated. TiO₂ nanoparticles are dispersed in B25 fuel at 50, 100, and 150 ppm concentrations.Subsequently, they are tested in a stationary research diesel engine at a rotational speed of 1500 rpm andspecific loads. Nanoparticles enhance combustion, offering increased cylinder gas pressure, net heatrelease rate, and reduced ignition delay period and combustion duration. The engine performance is enhanced more with increasing nanoparticle concentration. TiO₂ nanoparticles with a 150 ppm ratereduce brake-specific fuel consumption by 3.21% and increase the brake effective efficiency by 3.67%,on average, compared to B25 fuel without nanoparticles. CO emission and smoke opacity are reduced byup to 31.89% and 24.56% with TiO₂ nanoparticles. However, under the same operating conditions, NO emission increases to 30.58% compared to sole B25. Nevertheless, the NO emission of nanofuels is stillless than that of diesel fuel. This study's results indicate that using TiO₂ nanoparticles as a nano fueladditive can enhance the stationary engine's operation fueled with the biofuel mixture-diesel blend.
Quantitative assessment of postgraduate theses in Türkiye about yarn production technology
(Bursa Uludağ Üniversitesi, 2023-10-11) Var, Cansu; Palamutcu, Sema
Yarn and spinning technology is a complex process that is a combination of raw materials, machinery, and automation technology where continuous improvements, researches and innovations run progressively. For the evolution of spinning technology, academic publications, postgraduate theses, andtechnological contributions of related shareholders must be considered as adherent supplements. Aim ofthis study is to examine the accomplished 236 postgraduate theses related to conventional and noveltextile fibre types, staple spun/filament yarn technology and machinery, yarn types with structural andfunctional varieties, and modified spinning technologies in Turkish Universities. Moreover, it is aimed toreveal any trend in theses on yarn technology and the regional textile clusters in Türkiye. Themethodology of the pursuit is a quantitative assessment where postgraduate level, thesis subject, year ofthesis defence, and raw materials used in the theses are concerned. The findings showed that research ersfocussed on conventional spinning systems and yarns in parallel with the spinning capacity and importpotential of the country. Other extractions of the study are; classical ring system is mostly studied by there searchers, modern spinning technologies are included in many theses, reflections of globalcircumstances are distinguished in theses with keywords of manmade/recycled fibres, and blended yarns.
Using convolutional neural network for grape plant disease classification
(Bursa Uludağ Üniversitesi, 2023-09-03) Sofuoğlu, Cemal İhsan; Bırant, Derya
Plant disease classification is the use of machine learning techniques for determining the type of disease from the input leaf images of the plants based on certain features. It is an important research areasince early identification and treatment of plant disease is critical for saving crops, preventing agricultural disasters, and improving productivity in agriculture. This study proposes a new convolutional neuralnetwork model that accurately classifies the diseases on the plant leaves for the agriculture sectors. Itespecially works on the classification of plant diseases for grape leaves from images by designing a deep-learning architecture. A web application was also implemented to help the agricultural workers. The experiments carried out on real-world images showed that a significant improvement (8.7%) on averagewas achieved by the proposed model (98.53%) against the state-of-the-art models (89.84%) in terms of accuracy.

Browse

Browsing by Language "en"