Food irradiation is widely accepted as a proven and effective postharvest treatment to reduce the bacterial contamination, extend the shelf life and maintain the food quality. Spices and herbs are the most commonly irradiated commercial products. Low dose irradiation causes no adverse effects on the visual quality of fresh herbs and spices. The appearance and color of food influence the consumer’s product choice. Numerous studies are performed on the use of computer vision and image processing for the color evaluation in the food industry. In the present study, fresh cilantro was chosen as a model to estimate the change in the color parameters of gamma irradiated fresh cilantro leaves. Image analysis method was proposed as an alternative to conventional colorimeters for color measurement of irradiated fresh herbs and spices.
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The hydrocarbon detection method, based on the detection of hydrocarbons formed during irradiation, is one of the internationally accepted detection methods for irradiated foods. Radiolysis products, formed due to breakdown of unsaturated fatty acids by irradiation, are detected in this method. While no hydrocarbons were not found in the unirradiated hazelnut oil, hydrocarbons, namely 1-7 hexa-decadiene, 1- hexa-decene, n-penta-decane and 1- tetra-decene, but they were detected after irradiation at doses of 5 kGy or higher. It was found that irradiation induced the formation of hydrocarbons and when irradiation dose increased, the amount of hydrocarbons increased. The Rancimat process is widely used to define the amount of oxidation in foods containing fat. Analysis time is short as it is a very fast method. The induction time, showing the oxidation resistance of oils, decreased as irradiation dose increased. The possible relationship between the detected hydrocarbons and oxidative stability was examined and a negative correlation was found between the hydrocarbon and rancimat methods.
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A software was developed to use equipment component frequency data specific to the facility or provided from different sources in lost event probability calculations for risk-based inspection. Corrosion causes equipment aging and loss events in which hazardous substances are released uncontrollably. The API RP 581 Recommended Practise of the American Petroleum Institute is widely used in the calculation of corrosion-based loss event risks for static pressure equipment such as atmospheric tanks, heat exchangers, columns, reactors, and used for basis of the developed software. In API RP 581, the risk of loss event is defined as the product of the probability of failure and the severity of consequence. Equipment component generic failure frequencies are a variable at the probability of failure calculation. Current software use only equipment component generic failure frequencies given at API RP 581. For this reason, establishment-specific equipment component failure frequency data or data that can be obtained from other sources cannot be used. To solve this problem, a software based on API RP 581 methodology has been developed and provided with the opportunity for the user to enter equipment component failure frequency data from different sources. The findings showed that when using data from different literature sources, there are different results up to 1491% in the probability of failures. Since the increase in the probability of the failures will increase the risk, that creates results such as pulling the equipment inspection dates forward, performing more effective and therefore more costly inspections, increasing the precautions and costs to be taken. Therefore, software which are based on API RP 581 methodology should be developed in such a way that different generic frequency data can be used.
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In this study, a new Kirschner wire (K-wire) design was performed to fix bone fractures in orthopedic surgery. The numerical analyses were completed based on the finite element method (FEM), using Deform-3D software. In this kind of numerical analyses using the FEM, friction, material model, the load and boundary conditions must be defined correctly. It has been seen that the new design is more advantageous in terms of implant failure or stability of fracture fixation. In addition, a good compatibility was found between the experimental results and the finite element analysis (FEA) results. This confirmed the accuracy of the finite element model. Therefore, this finite element model can be used reliably in drilling processes. We believe that with the use of new design investigated may have the role on the patients taking away from recurrent anesthesia and orthopaedic surgical risk.
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This study introduces (p,q)-hybrid Durrmeyer-Stancu type linear positive operators, which are generalized forms of q-hybrid Durrmeyer-Stancu-type linear positive operators and examines their approximation properties. The first modulus of continuity on a finite interval is introduced using Peetre’s K-functional. Then, the weighted approximation theorem in a weighted space is provided using Gadzhiev’s weighted Korovkin-type theorem. Finally, these operators’ rates of convergence are obtained for the continuous functions.
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Increased carbon dioxide emissions in the atmosphere and their harmful effects on the atmosphereand humans in general, this increase leads to significant climate changes that continue to affect thecoming years. There is an urgent need to develop and increase research on clean energy and findthe impact of weather changes, on the turbine's efficiency as a result of density fluctuate. A twophase flow homogeneous model used to find these changes. The study analyzed the effect ofatmospheric conditions, including temperature, humidity and pressure on kinetic energy in thewind through its effect on air density and find the rate of change resulting from these conditions,the air is dry and when the air is humid so the increase or decrease of this energy will affectpositively or negatively on the performance of the turbine. The city of Mersin was selected inTurkey for this analysis through the application of air conditions obtained from the GeneralDirectorate of Meteorology in Ankara and resolve for accurate and detailed for each seasonthroughout the year 2017, where the temperature varies from 0 to 35 degrees Celsius and humidityof 15 to 99 percent, as well as air pressure from 966.95417 to 1025.9 hPa. The effect of moisturewas studied mainly by using thermodynamic laws in this paper.
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Q-Blade simulation tool was employed in modal analysis of horizontal axis wind turbine bladewith three distinct configurations (with spar, no spar and solid) to determine the configuration withadequate structural integrity under aerodynamic loading conditions. The blade configurations wereanalysed in four different modes based on the flapwise and edgewise response of the blade toaerodynamic loads/forces, and the corresponding modal eigenfrequencies were evaluated.Bending due to combined effects of flapwise and edgewise modal frequencies on the blade werealso evaluated at different rotor blade speeds ranging from 2-8m/s. It was observed that the solidblade configuration had the least modal eigenfrequencies for both flapwise and edgewise responsein all the four modes as follows: 22.03 and 62.60 Hz in mode 1, 58.0 and 212.8 Hz in mode 2,122.6 and 600.6 Hz in mode 3, 194.4 and 1118.9 Hz in mode 4. The rotor blade configuration withNo spar had the highest modal eigenfrequencies for both flapwise and edgewise response in all thefour modes followed by the blade configuration with spar. Bending of the rotor blade due tocombined effects of flapwise and edgewise modal frequencies at the aforementioned blade speedswere also highest in blade configuration with No spar and lowest in the solid blade configuration.The low modal eigenfrequencies and low bending values on the solid blade configuration implyhigh stiffness and strength but with additional mass, which is why 6000 series aluminium wasselected in order to minimize the extra weight.
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Modelling of process parameters and its validation in Aluninium production industries poses greatchallenges in the production of Aluminium sheets in Aluminium Manufacturing companies. Thisresearch therefore focused on the modelling and validation of production parameters of unalloyedAluminium sheets in Aluminium manufacturing industries. The process parameters investigatedwere temperature (T), pressure (P) and percentage by volume of Aluminium (Ap) used. The effectsof these process parameters on the mechanical properties of the developed unalloyed Aluminiumsheets were modelled to ease Aluminium manufacturing processes in Aluminium industries. Fromthe plots obtained, it was observed that the optimal tensile strength, young modulus of elasticity,shear modulus and Brinell hardness number were 621MPa, 69GPa, 25.5GPa, and 61 attemperature of 1921°C, 1610°C, 1442°C and 1800°C respectively. In comparison with pressure,the obtained values for optimal tensile strength, young modulus of elasticity, shear modulus andBrinell Hardness Number were 562MPa, 68GPa, 26.2GPa and 61 at pressure of 72GPa, 69.5GPa,69.5GPa and 69.5GPa respectively. Moreover, empirical Models were also developed forpredicting the mechanical properties such as tensile strength, young modulus of elasticity, shearmodulus and hardness for the produced unalloyed Aluminium sheets. The models were validatedusing coefficient of determination (R2) and mean absolute percentage error (MAPE). Thecoefficient of determination (R2) obtained ranges from 0.9213 (92.13%) to 0.9911 (99.11%) whichindicates that a substantial good fit was achieved by the regression models developed. The meanabsolute percentage error of the developed models also ranges from 0.46% to 3.38% which wasbelow 10% recommended. The values obtained from the validation of these models were thereforefound to be satisfactory, and shows good predictability of the model and its adequacy. Finally, theresults obtained show that temperature and pressure had great effects on the mechanical propertiesof the produced unalloyed Aluminium sheets.
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This article aims to solve the mathematical model developed for machine tool vibrations byemploying Differential Transformation Method (DTM). Multi-step differential transformationmethod is used as it has been shown to have good accuracy in physical applications.Nondimensionalization (scaling) technique is used in order to fully understand the physical effectsof each varying parameter. Transformed function of delayed nonlinear velocity terms areexplained. MatLab® software is used for DTM solutions. The equation of motion is solved withthe DDE23 function in MatLab® software as well as with MatLab®/Simulink® software tocompare the results. The solution of the fundamental DTM which is obtained by using the constanttransformed function values which differ from other methods after a certain time period. However,the results obtained with the transformed functions for different values at each sampling time(Multi-Step DTM) give very close results to Simulink® and DDE23.
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In this study, the effect of welding speed (3, 3.5, 4 m/min) and focal length (0, 1.4 mm) on themechanical properties of the welded structure was investigated in the overlap type joining of 1.2mm sheet thickness DP600 dual phase steel sheet material by fiber laser welding method. For thispurpose, tensile-shear tests were performed on the samples joined by laser welding method, andthe tensile strength and elongation amounts were determined. Microstructure investigation andmicrohardness measurements of the welded area were carried out. It is determined that weld jointshape and penetration depth changes according to focal length distance and welding speed, andwith the maximum welding speed specimens has the minimum penetration depth. Tensile-shearstrength values decreased depending on the increased welding speed for both focal lengthspecimens. It is observed that the microhardness results were affected by welding speed and focallengths. In 0 mm focal length distance specimens’ hardness values increased according to theincreased welding speed, but for –1.4 mm focal length distance the microhardness valuesdecreased with an increased welding speed. The fracture zones and fracture surface morphologyalso affected by welding speed and focal distance. In 0 mm focal length, all the specimen fracturedin base metal with a ductile fracture morphology, but in the –1.4 mm focal length, specimensfractured from the zones which are closer to HAZ and FZ with a brittle fracture morphology.
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