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Transfer of the designs to the surface of ceramic wall tiles is performed by ink-jet digital printing technology. CMYK ink colors are used in ink-jet printing technology. The similarities between hues for various color types make it difficult to come up with different designs. In this study, the development of a wall tile matte glaze recipe with high color activity, which can be worked with CMYK+Pink ink colors. Different recipes were developed by increasing the amount of calcite, dolomite, zinc oxide and magnesite ratios, respectively. Firstly, matt glaze recipes are prepared and employed on wall tile with engobe, followed by CMYK+Pink ink digital decor application. Succeeding the sintering of tiles, L,a,b color measurements of ink decorated glaze recipes were made, and it was determined that the value of 'a' increased from 15.35 to 22.18. The hue angle and chroma values of the recipies were calculated. No significant differences were observed in the color activities of the colors other than pink, and the desired pink color intensity was achieved with one of the new wall tile matte glaze recipes. It was observed that the pink color intensity increased with the increase in the amount of CaO in the content of the matte glaze recipe. The color activity of the pink color could is not obtained in the glaze recipe where the amount of ZnO increased. [ABSTRACT FROM AUTHOR]

Capacitated lot sizing is a frequently encountered production-planning problem in manufacturing companies. However, many real life factors are usually not taken into account during the model development phase for these problems. In this study, an integrated lot-sizing and scheduling problem of a paper bag production firm is considered. A mixed integer mathematical programming model is proposed for modeling and solving the problem. Setup cost/time between product and period changes are considered in the proposed model. It is aimed to minimize the total cost of production, holding inventory, backorder, procurement and setup for product type change and product period change. It is observed that productive utilization of manufacturing resources and the generation of more effective production plans are possible by the application of the proposed model. [ABSTRACT FROM AUTHOR]

Synthetic dyes are widely used as colorants in many industrial areas such as paper, plastic, leather, wool and textile. When wastewater containing these dyes is released into the receiving water environment without treatment, it reduces the light transmittance of the aquatic environment, preventing photosynthetic activities in aquatic life, and harming the environment, animal and human life cycles. Therefore, dyes must be purified from water. Adsorption is one of the methods in which cost-effective, easy-to-apply and effective removal efficiencies are obtained. In this study, CTS/nanoclay beads containing chitosan (CTS) and nanoclay were prepared for use in dye adsorption. Acid Violet 90 (AV90), a metal-complex dye, was used in the experiments. CTS and CTS/nanoclay beads were prepared by the drop method. The morphological structures of the beads were investigated by scanning electron microscopy (SEM) and functional groups were investigated by Fourier transmission infrared spectroscopy (FT-IR). The effect of initial pH and dye concentration on AV90 adsorption with spheres was investigated. Experiments were carried out in batch system. The highest dye removal was obtained at pH 2. Adsorption isotherm models (Langmuir, Freundlich and Temkin) were applied to the experimental data obtained and it was seen that Langmuir was the most suitable model for AV90 adsorption. The adsorption capacities (qm, mg/g) obtained from the Langmuir isotherm model are 26.81 mg/g for CTS and 91.74 mg/g for CTS/nanoclay. In this study, it was seen that the beads containing nanoclay can be used successfully in dye adsorption. [ABSTRACT FROM AUTHOR]

The importance of nanoscale devices is increasing day by day. Therefore, nanobeams, nanoplates, nanorods have been the focus of engineers in nanoelectromechanical structures. From that point of view, the nonlinear behaviour of three supported nanobeams is investigated in this paper numerically. Firstly, linear natural frequencies were calculated; and then, nonlinear natural frequencies were found thanks to nonlinear correction terms. Nonlinear natural frequencies versus amplitude and nonlinear frequency response curves are plotted to clarify the nonlinear behaviour. Nonlocal parameters, second support position and different modes effects are examined comprehensively. In addition, the different first and last support types are investigated. It is shown that nonlocal parameters and second support position have great importance for nanobeam. The glorious effect is obtained highest modes. [ABSTRACT FROM AUTHOR]

During the Covid-19 pandemic, online shopping spread widely, and its quality is later improved and made permanent. Before it is enabled, online shopping is a very expensive and challenging process for businesses to manage, especially since customers can set a time window for their products. Customers may lose business and incur expenditures if the products they requested are not timely and of the appropriate quality supplied to them. Due to this, it is crucial to handle this difficult process well, and for this to happen, both in- and out-of-warehouse procedures must be carried out simultaneously. Order batching, a branch of the order picking process inside the warehouse, and vehicle routing, a distribution problem outside the warehouse, are these processes. The Combined Order Batching and Vehicle Routing Problem arises if these two procedures are considered as being integrated. The linked problem becomes the Integrated Order Batching and Vehicle Routing Problem with Time Window (OB_VRP_TW) when the time component is added. This study categorized and analyzed papers in the literature for OB_VRP_TW and created a novel mixed integer nonlinear programming model. Since just a part of the small data set can be handled by packet encoding programs and this developed model is linearized under specific circumstances, a metaheuristic search algorithm called the genetic algorithm is offered to solve that problem. The test data of the sub-problems were searched for, and the test data for the problem were added to the literature by combining the test data in the literature and some data of a company whose problems were applied, as there were no test data for the current problem in the relevant area. [ABSTRACT FROM AUTHOR]

The Seru Production System is a cellular production system that originated in Japanese manufacturing industry. Seru Production Systems evaluates the efficiency of assembly line and the flexibility of job-shop production together. Workers must be cross-trained and have advanced competency levels for different operations in Seru Production Systems. In this study, the employees' production rate at different labor competency levels assigned in the Seru Production System is compared with production rate they put forward while working in traditional assembly line production system. This paper examines various competence levels of employees capable of producing the entire product and their effects on total production output. First, traditional assembly line production rates were calculated via integer programming using well-known test problems. Then, these test problems were converted into serus run by workers with different competence levels, relevant operation times were calculated, and production rates were obtained. Paired t test is used to compare the production rates. The results show that Seru Production Systems provided more production than traditional assembly line. Moreover, a 2-way analysis of variance is applied to show that the output rates obtained from the traditional assembly line and Seru production methods are affected by different test problems and different worker competency levels. [ABSTRACT FROM AUTHOR]

In this paper, a novel operational amplifier (op-amp) model was created by redesigning the internal structure of conventional op-amp (ua741 family) circuit element with the linear dopant drift TiO2 memristor (LDDTM) emulator model. The optimized operating conditions and states of this novel op-amp model were determined. The memristor based op-amp model was used as an amplifier element in the phase shift oscillator (PSO) circuit which is one of the RC oscillators. With the novel new phase shift oscillator, the oscillation settling time, start time, fast Fourier transform (FFT) analysis and their effects on the output parameters are investigated both experimentally and simulated. The new oscillator model novel in this study is evaluated in detail not only in the middle frequency region, but also in the high and low frequency regions. In addition, the efficiency of these circuits has been merged with the experimental circuits, and the accuracy and practicality of the novel op-amp model has been comprehensively studied theoretically and supported by simulation and experimental results. Finally, both experimental and simulation results of the oscillator circuits realized with the novel op-amp model are shown in detail in tables. [ABSTRACT FROM AUTHOR]

This paper studies a two-dimensional two-stage guillotine cutting stock problem which includes determination of how the items should be cut from stock panels in an optimal way, by developing and applying different solution approaches. An integer programming model with new features is proposed. A random key based genetic algorithm is utilized to obtain feasible solutions, and by applying a local search within the algorithm, a hybrid structure is acquired. Besides, a novel two-stage math-heuristic solution method is proposed. In the first stage of this method, a relaxation of the problem is solved; in the second, this solution is improved. The time to obtain the results of the developed two-stage math-heuristic solution approach is significantly lower than the other methods given in the article. Optimal solution values were obtained in 26 of 30 test problems taken from the literature with the proposed mathematical model, in 14 with mathematical programming based heuristic method, and in 16 with a random key based genetic algorithm. [ABSTRACT FROM AUTHOR]

This paper aims to develop a high-performance method for designing Finite Impulse Response (FIR) filters that effectively control the over-frequency response parameters. The proposed approach involves designing an optimal FIR filter based on an Infinite Impulse Response (IIR) filter, considering various parameters such as pass and stop band ripples, stop band attenuation, transition bandwidth, and linear phase response. The advantages of the IIR filter's better frequency response are utilized in this design. The parameters of Butterworth and Chebyshev filters are optimized using Artificial Bee Colony (ABC) and Particle Swarm Optimization (PSO) algorithms, incorporating novel fitness functions based on different distance metrics. Visual examination of the filtered signals shows that the proposed algorithm reduces phase delay compared to traditional filters. Additionally, the performance of the designed filter is evaluated by decomposing a sinusoidal signal with four different frequencies into its sub-bands. The numerical results demonstrate that the proposed approach achieves more precise decomposition compared to commonly used traditional filters. [ABSTRACT FROM AUTHOR]

In this paper, effect of small deviations in the parameters that appear either in the definition or determination of a physical problem to the resultant calculated value. Within the study, Perturbation theory and Asymptotic Series expansions have been used as mathematical tools. In this work, perturbation theory has been handled in two alternative ways: numerical and analytical. Electromagnetic waves has been dealed extensively. Electromagnetic propagation equation has been nondimensionalised and presented via asymptotic series approach. Spatial Fourier transformation provides singular perturbation application to the equation. Validity of the solution has been investigated. This manuscript also concerns the electromagnetic feature extraction of the multilayered properties by the inverse scattering theory approach. In this work, in order to characterize the unknown or ambiguous part of the structure, random modeling of the parameters was introduced. Monte Carlo methods are used to calculate the resultant randomness effect. The description of any parameter, including thickness, with any probability density function (pdf) to represent nonnegative/bounded/unbounded cases and any combination of all these parameters, is represented in a framework. Skewness and kurtosis values are added to the output structure in order to lead complex analysis on the output descriptions. In this work, depending on the structure or aim of the analysis, the permittivity or the permeability of a layer is randomized. The overall reflection coefficient is calculated via recursive analysis. [ABSTRACT FROM AUTHOR]

With the rapid integration of digital technologies into e-commerce platforms, online sales have increased dramatically in recent years. Additionally, customers' awareness of the global competition among hundreds of e-commerce companies has increased their expectations such as high quality, low price, fast and free delivery like never before. In response, e-commerce companies have started revisiting their logistics systems to survive in such a business environment by meeting rising expectations and minimizing operational costs. Thus, most companies have been focused on order-picking processes, which are characterized by high operating times and labor costs. Accordingly, collaborative robots (cobots) have been used in many warehouses to make order-picking operations more efficient and profitable. Depending on the distance between pick locations, a cobot can either be ridden by the order picker or autonomously move to the next pick location while the order picker is walking. This paper proposes a bi-level programming model to find the optimal designs of order-picking warehouses employing collaborative robots. The top-level model is used to determine the optimal shape factor (width-to-depth ratio) minimizing the order-picking time; whereas, the bottom-level model determines the optimal route and collaboration strategy. Based on Monte Carlo simulation, it is shown that the shape factor significantly affects the length of an order-picking tour when the pick-list size is small. However, it is concluded that the optimal shape factor varies depending on the pick-list size. [ABSTRACT FROM AUTHOR]